Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 12/07/14
AREA FORECAST DISCUSSION...UPDATED
NWS TAMPA BAY RUSKIN FL
225 PM EST FRI DEC 5 2014
.SYNOPSIS...
18Z WATER VAPOR AND H4 RAP ANALYSIS CONTINUES TO SHOW AN UNAMPLIFIED
UPPER LEVEL PATTERN IN PLACE ACROSS THE CONUS. ONLY REAL FEATURE OF
NOTE IS A SHORTWAVE TROUGH EJECTING OUT OF THE SW STATES ACROSS THE
SOUTHERN PLAINS. THIS IMPULSE WILL CONTINUE EASTWARD TOWARD THE TN
VALLEY AND SOUTHEASTERN STATES FOR THE FIRST HALF OF THE WEEKEND...
BUT ALL SIGNIFICANT SENSIBLE WEATHER / SYNOPTIC FORCING FOR ASCENT
ASSOCIATED WITH THIS ENERGY IS STILL EXPECTED TO REMAIN TO THE NORTH
OF OUR FORECAST REGION. CURRENTLY THE UPPER LEVEL PATTERN OVER THE
EASTERN GULF AND FLORIDA PENINSULA IS ONE OF WEAK RIDGING. THIS
RIDGE WILL BE BROKEN DOWN OVER THE NEXT 24 HOURS AS THE SHORTWAVE
PASSES TO OUR NORTH...BUT ONCE AGAIN ANY SIGNIFICANT HEIGHT FALLS
WILL BE CONFINED TO AREAS WELL NORTH OF US. 05/12Z KTBW SOUNDING
PROFILE SHOWS A WELL DEFINED SUBSIDENCE INVERSION ASSOCIATED WITH
THE RIDGING ALOFT LOCATED AROUND 700MB WITH A FAIRLY MOIST COLUMN
BELOW THIS LEVEL...AND QUITE DRY COLUMN ABOVE. THE PW VALUE WAS
CALCULATED AROUND 1.3"...WHICH DESPITE THE DRIER COLUMN ALOFT IS
STILL A BIT ABOVE CLIMATOLOGY FOR THE FIRST WEEK OF DECEMBER.
AT THE SURFACE...LARGE HIGH PRESSURE SYSTEM RIDGES DOWN THE EASTERN
SEABOARD TO THE GULF OF MEXICO/FL PENINSULA PUTTING OUR REGION
WITHIN A SWATH OF EASTERLY LOW LEVEL SYNOPTIC FLOW.
&&
.SHORT TERM (REST OF TODAY THROUGH SATURDAY)...
LATE AFTERNOON / EARLY EVENING...
REGIONAL RADARS SHOWING A PERSISTENT BAND OF SHOWERS MIGRATING
WESTWARD FROM THE FL EAST COAST INTO EASTERN/NORTHERN POLK COUNTY
THE PAST SEVERAL HOURS. THIS BAND APPEARS TO BE THE RESULT OF A WEAK
ZONE OF LOW LEVEL CONVERGENCE BASED ON COASTAL OBSERVATIONS ALONG
THE FL EAST COAST. THE CONVERGENCE HOWEVER IS SUBTLE AND IS A GREAT
EXAMPLE OF HOW ONLY SMALL DIFFERENCES IN MESOSCALE PATTERNS CAN HAVE
HUGE IMPACTS ON A SMALL AREAS FORECAST. PAST SEVERAL RUNS OF THE
HRRR HAVE INITIALIZED THE RAIN BAND WELL...BUT THEN SHOWED
SIGNIFICANT DECREASE IN COVERAGE WITHIN 3 TO 4 HOURS. THIS HAS NOT
BEEN HAPPENING SO FAR...AND DO NOT HAVE MUCH CONFIDENCE IN THE HRRR
CONVECTIVE SOLUTION FOR THE REST OF THE AFTERNOON. BASICALLY WITH
THE CONVERGENCE IN PLACE...THIS BAND IS LIKELY TO LINGER IN SOME
FORM WITHIN ITS CURRENT GENERAL LOCATION UNTIL WE BEGIN TO LOSE
DIURNAL HEATING IN A COUPLE OF HOURS. HAVE INCREASED THE POPS TO THE
LIKELY RANGE ALONG THIS CORRIDOR THROUGH 4PM AND THEN BEGIN TO TAPER
THINGS OFF. ELSEWHERE ONLY BRIEF ISOLATED TO WIDELY SCT AND LESS
ORGANIZED SHOWERS/SPRINKLES ARE EXPECTED. OUTSIDE OF THIS MAIN
BAND...THE MAJORITY OF THE REMAINING DAYLIGHT HOURS WILL BE DRY.
TEMPERATURES ARE RIGHT ON FORECAST TRACK (EXCEPT FOR UNDER THAT
PERSISTENT RAINBAND) WITH UPPER 70S NORTH AND LOWER 80S SOUTH.
TONIGHT...
SCT SHOWER/SPRINKLE ACTIVITY SHOULD DIMINISH EARLY...
RESULTING IN A MOST DRY NIGHT. SREF GUIDANCE IS SUGGESTING ONCE
AGAIN THAT SOME FAIRLY WIDESPREAD STRATUS/FOG WILL DEVELOP AFTER
MIDNIGHT FOR OUR NORTHERN NATURE COAST ZONES....WITH MORE PATCHY FOG
DEVELOPING FURTHER SOUTH DOWN THE I-75 CORRIDOR. WILL INCLUDE
MENTION OF PATCHY FOG FOR ALL OVERNIGHT...WITH AREAS OF DENSE FOG
MENTIONED FOR CITRUS/LEVY COUNTIES. LOW TEMPERATURES BY DAWN
SATURDAY MORNING APPEAR SEASONABLE WITH A MOS BLEND RESULTING IN
UPPER 50S AROUND CHIEFLAND TO LOWER 60S FOR TAMPA/LAKELAND...AND
LOWER/MID 60S FURTHER SOUTH.
SATURDAY...
SHORTWAVE TO OUR NORTH MIGRATES FROM THE TN VALLEY EARLY IN THE DAY
TOWARD THE CAROLINA COAST BY EVENING. AT THE SURFACE...ASSOCIATED
SURFACE REFLECTION LOW PRESSURE ADVANCES FROM KY TO THE MID-ATLANTIC
STATES WITH A COLD FRONT TRAILING SOUTHWESTWARD THROUGH MS/AL/GA.
THE SURFACE PATTERN FOR THE FLORIDA PENINSULA WILL WEAKEN AS THE
RIDGE OF HIGH PRESSURE IS FORCED EAST INTO THE ATLANTIC. LOCAL
GRADIENT WILL BECOME QUITE LIGHT THROUGH THE DAY. UPPER RIDGE WILL
BE BEATEN DOWN COMPARED TO FRIDAY...HOWEVER...THE ATMOSPHERIC
POTENTIAL WILL REMAIN QUITE WARM AND EXPECTING ANOTHER DAY OF UPPER
70S NORTH AND LOWER 80S SOUTH. THE WARM TERRESTRIAL TEMPERATURES...
COOLER SHELF WATERS...AND LIGHT GRADIENT SHOULD ACTUALLY ALLOW A
DEFINED SEA-BREEZE CIRCULATION TO DEVELOP FOR THE AFTERNOON HOURS.
THE SYNOPTIC EASTERLY FLOW BEING GONE...WILL NOT EXPECT ANY MORE OF
THESE SPEED CONVERGENCE SHOWERS MIGRATING OVER FROM THE FL EAST
COAST. HOWEVER...IT MAY BE DECEMBER...BUT MANY OF THE HIGH
RESOLUTION CONVECTION ALLOWING GUIDANCE MEMBERS ARE HINTING AT THE
POTENTIAL FOR A FEW SEA-BREEZE CONVERGENCE SHOWERS ALONG THE I-75
CORRIDOR DURING THE AFTERNOON. GENERALLY SPEAKING THESE MODELS CAN
BE A BIT AGGRESSIVE WITH THIS TYPE OF CONVECTION...BUT CAN NOT RULE
OUT A FEW ISOLATED CELLS. HAVE INCLUDED A 20% AFTERNOON POP FOR A
BRIEF SHOWER AWAY FROM THE COAST FOR THE NORTHERN HALF OF THE
REGION...WHERE LAND/WATER DIFFERENCE IS LIKELY TO RESULT IN THE
STRONGEST SEA-BREEZE CIRCULATION. IF WE DO GET A FEW ISOLATED
SHOWERS...THEY WILL NOT LAST LONG AND SHOULD DISSIPATE QUICKLY AS
THE SUN BEGINS TO GET LOW IN THE SKY EARLY SATURDAY EVENING.
&&
.MID-LONG TERM (SATURDAY NIGHT-FRIDAY)...
CONTINUE TO EXPECT WEAK AND MAINLY DRY FRONT TO MOVE OVER THE REGION
SATURDAY NIGHT-SUNDAY WITH ONLY A SLIGHT CHANCE OF RAIN ASSOCIATED
WITH THE FRONT. DRIER HIGH PRESSURE QUICKLY BUILDS DOWN THE EASTERN
SEABOARD SLIGHTLY DROPPING TEMPERATURES LATER SUNDAY INTO EARLY NEXT
WEEK KEEPING TO AROUND SEASONAL NORMALS. RE-ENFORCING DOME OF HIGH
PRESSURE DROPPING OUT OF CANADA TO BUILD INTO THE REGION BY MID WEEK
KEEPING NORTHEASTERLY LOW LEVEL FLOW. MODELS DIFFER ON JUST HOW COLD
THIS AIRMASS IS BUT TEMPERATURES EXPECTED TO RUN AT LEAST SLIGHTLY
BELOW NORMAL TUE-FRI AREAWIDE.
&&
.AVIATION...
VFR CONDITIONS PREVAIL ACROSS THE REGION THIS AFTERNOON AND SHOULD
CONTINUE THROUGH THE EVENING HOURS. ALTHOUGH THE MOST WIDESPREAD
LOWER STRATUS AND FOG IS EXPECTED TO REMAIN TO THE NORTH OF THE
FORECAST TERMINALS...PATCHES OF LIGHT NIGHT / EARLY MORNING FOG ARE
STILL EXPECTED FURTHER SOUTH AWAY FROM THE IMMEDIATE COAST. HAVE
ADDED MVFR VIS TO THE TAFS FOR KLAL...KPGD...KFMY AND KRSW FOR A FEW
HOURS EARLY SATURDAY MORNING. THESE RESTRICTIONS SHOULD LIFT BY
14-15Z WITH VFR CONDITIONS THE REMAINDER OF THE DAY. WINDS WILL BE
LIGHT SATURDAY MORNING...BUT EXPECT A SHIFT OF WINDS TO A MODERATE
ONSHORE DIRECTION DURING THE AFTERNOON FOR KSRQ...KPIE...AND KTPA.
&&
.MARINE...
OFFSHORE EASTERLY BREEZE WILL CONTINUE THROUGH TODAY IN THE EASTERN
GULF OF MEXICO AS HIGH PRESSURE REMAINS CENTERED NORTH OF THE
REGION. GRADIENT WINDS BEGIN TO RELAX BY SATURDAY AFTERNOON HELPING
A SEA BREEZE CIRCULATION SET UP NEAR THE COAST...HOWEVER NOT
EXPECTING ANY SIGNIFICANT SHOWER OR THUNDERSTORM ACTIVITY OVER THE
WATERS. A WEAK AND RELATIVELY DRY COLD FRONT WILL PUSH THROUGH THE
AREA ON SUNDAY HELPING TO REINFORCE HIGH PRESSURE AND OFF SHORE
WINDS. NO SIGNIFICANT MARINE HEADLINES EXPECTED OVER THE WEEKEND.
&&
.FIRE WEATHER...
RELATIVE HUMIDITY WILL REMAIN ABOVE CRITICAL LEVELS THROUGH THE
WEEKEND. ONLY FIRE WEATHER CONCERN WOULD BE THE POTENTIAL FOR AREAS
OF LATE NIGHT AND EARLY MORNING FOG THROUGH SUNDAY MORNING. THE NEXT
COLD FRONT IS SCHEDULED TO ARRIVE DURING THE DAY ON SUNDAY. THIS
FRONT WILL PASS MAINLY DRY AND RESULT IN SOMEWHAT COOLER CONDITIONS
FOR THE EARLY PORTION OF NEXT WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 65 79 63 77 / 10 10 10 10
FMY 65 82 62 80 / 10 10 10 10
GIF 63 80 61 77 / 0 20 10 20
SRQ 64 78 61 76 / 10 0 10 10
BKV 61 80 55 77 / 0 20 10 10
SPG 66 78 64 76 / 10 10 10 10
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
SYNOPSIS/SHORT TERM/AVIATION/MARINE/FIRE WX...MROCZKA
MARINE...BARRON
LONG TERM...PAXTON
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
200 PM EST FRI DEC 5 2014
.UPDATE (REST OF TODAY AND TONIGHT)...
18Z WATER VAPOR AND H4 RAP ANALYSIS CONTINUES TO SHOW AN UNAMPLIFIED
UPPER LEVEL PATTERN IN PLACE ACROSS THE CONUS. ONLY REAL FEATURE OF
NOTE IS A SHORTWAVE TROUGH EJECTING OUT OF THE SW STATES ACROSS THE
SOUTHERN PLAINS. THIS IMPULSE WILL CONTINUE EASTWARD TOWARD THE TN
VALLEY AND SOUTHEASTERN STATES FOR THE FIRST HALF OF THE WEEKEND...
BUT ALL SIGNIFICANT SENSIBLE WEATHER / SYNOPTIC FORCING FOR ASCENT
ASSOCIATED WITH THIS ENERGY IS STILL EXPECTED TO REMAIN TO THE NORTH
OF OUR FORECAST REGION. CURRENTLY THE UPPER LEVEL PATTERN OVER THE
EASTERN GULF AND FLORIDA PENINSULA IS ONE OF WEAK RIDGING. THIS
RIDGE WILL BE BROKEN DOWN OVER THE NEXT 24 HOURS AS THE SHORTWAVE
PASSES TO OUR NORTH...BUT ONCE AGAIN ANY SIGNIFICANT HEIGHT FALLS
WILL BE CONFINED TO AREAS WELL NORTH OF US. 05/12Z KTBW SOUNDING
PROFILE SHOWS A WELL DEFINED SUBSIDENCE INVERSION ASSOCIATED WITH
THE RIDGING ALOFT LOCATED AROUND 700MB WITH A FAIRLY MOIST COLUMN
BELOW THIS LEVEL...AND QUITE DRY COLUMN ABOVE. THE PW VALUE WAS
CALCULATED AROUND 1.3"...WHICH DESPITE THE DRIER COLUMN ALOFT IS
STILL A BIT ABOVE CLIMATOLOGY FOR THE FIRST WEEK OF DECEMBER.
AT THE SURFACE...LARGE HIGH PRESSURE SYSTEM RIDGES DOWN THE EASTERN
SEABOARD TO THE GULF OF MEXICO/FL PENINSULA PUTTING OUR REGION
WITHIN A SWATH OF EASTERLY LOW LEVEL SYNOPTIC FLOW.
&&
.SHORT TERM (REST OF TODAY THROUGH SATURDAY)...
LATE AFTERNOON / EARLY EVENING...
REGIONAL RADARS SHOWING A PERSISTENT BAND OF SHOWERS MIGRATING
WESTWARD FROM THE FL EAST COAST INTO EASTERN/NORTHERN POLK COUNTY
THE PAST SEVERAL HOURS. THIS BAND APPEARS TO BE THE RESULT OF A WEAK
ZONE OF LOW LEVEL CONVERGENCE BASED ON COASTAL OBSERVATIONS ALONG
THE FL EAST COAST. THE CONVERGENCE HOWEVER IS SUBTLE AND IS A GREAT
EXAMPLE OF HOW ONLY SMALL DIFFERENCES IN MESOSCALE PATTERNS CAN HAVE
HUGE IMPACTS ON A SMALL AREAS FORECAST. PAST SEVERAL RUNS OF THE
HRRR HAVE INITIALIZED THE RAIN BAND WELL...BUT THEN SHOWED
SIGNIFICANT DECREASE IN COVERAGE WITHIN 3 TO 4 HOURS. THIS HAS NOT
BEEN HAPPENING SO FAR...AND DO NOT HAVE MUCH CONFIDENCE IN THE HRRR
CONVECTIVE SOLUTION FOR THE REST OF THE AFTERNOON. BASICALLY WITH
THE CONVERGENCE IN PLACE...THIS BAND IS LIKELY TO LINGER IN SOME
FORM WITHIN ITS CURRENT GENERAL LOCATION UNTIL WE BEGIN TO LOSE
DIURNAL HEATING IN A COUPLE OF HOURS. HAVE INCREASED THE POPS TO THE
LIKELY RANGE ALONG THIS CORRIDOR THROUGH 4PM AND THEN BEGIN TO TAPER
THINGS OFF. ELSEWHERE ONLY BRIEF ISOLATED TO WIDELY SCT AND LESS
ORGANIZED SHOWERS/SPRINKLES ARE EXPECTED. OUTSIDE OF THIS MAIN
BAND...THE MAJORITY OF THE REMAINING DAYLIGHT HOURS WILL BE DRY.
TEMPERATURES ARE RIGHT ON FORECAST TRACK (EXCEPT FOR UNDER THAT
PERSISTENT RAINBAND) WITH UPPER 70S NORTH AND LOWER 80S SOUTH.
TONIGHT...
SCT SHOWER/SPRINKLE ACTIVITY SHOULD DIMINISH EARLY...
RESULTING IN A MOST DRY NIGHT. SREF GUIDANCE IS SUGGESTING ONCE
AGAIN THAT SOME FAIRLY WIDESPREAD STRATUS/FOG WILL DEVELOP AFTER
MIDNIGHT FOR OUR NORTHERN NATURE COAST ZONES....WITH MORE PATCHY FOG
DEVELOPING FURTHER SOUTH DOWN THE I-75 CORRIDOR. WILL INCLUDE
MENTION OF PATCHY FOG FOR ALL OVERNIGHT...WITH AREAS OF DENSE FOG
MENTIONED FOR CITRUS/LEVY COUNTIES. LOW TEMPERATURES BY DAWN
SATURDAY MORNING APPEAR SEASONABLE WITH A MOS BLEND RESULTING IN
UPPER 50S AROUND CHIEFLAND TO LOWER 60S FOR TAMPA/LAKELAND...AND
LOWER/MID 60S FURTHER SOUTH.
SATURDAY...
SHORTWAVE TO OUR NORTH MIGRATES FROM THE TN VALLEY EARLY IN THE DAY
TOWARD THE CAROLINA COAST BY EVENING. AT THE SURFACE...ASSOCIATED
SURFACE REFLECTION LOW PRESSURE ADVANCES FROM KY TO THE MID-ATLANTIC
STATES WITH A COLD FRONT TRAILING SOUTHWESTWARD THROUGH MS/AL/GA.
THE SURFACE PATTERN FOR THE FLORIDA PENINSULA WILL WEAKEN AS THE
RIDGE OF HIGH PRESSURE IS FORCED EAST INTO THE ATLANTIC. LOCAL
GRADIENT WILL BECOME QUITE LIGHT THROUGH THE DAY. UPPER RIDGE WILL
BE BEATEN DOWN COMPARED TO FRIDAY...HOWEVER...THE ATMOSPHERIC
POTENTIAL WILL REMAIN QUITE WARM AND EXPECTING ANOTHER DAY OF UPPER
70S NORTH AND LOWER 80S SOUTH. THE WARM TERRESTRIAL TEMPERATURES...
COOLER SHELF WATERS...AND LIGHT GRADIENT SHOULD ACTUALLY ALLOW A
DEFINED SEA-BREEZE CIRCULATION TO DEVELOP FOR THE AFTERNOON HOURS.
THE SYNOPTIC EASTERLY FLOW BEING GONE...WILL NOT EXPECT ANY MORE OF
THESE SPEED CONVERGENCE SHOWERS MIGRATING OVER FROM THE FL EAST
COAST. HOWEVER...IT MAY BE DECEMBER...BUT MANY OF THE HIGH
RESOLUTION CONVECTION ALLOWING GUIDANCE MEMBERS ARE HINTING AT THE
POTENTIAL FOR A FEW SEA-BREEZE CONVERGENCE SHOWERS ALONG THE I-75
CORRIDOR DURING THE AFTERNOON. GENERALLY SPEAKING THESE MODELS CAN
BE A BIT AGGRESSIVE WITH THIS TYPE OF CONVECTION...BUT CAN NOT RULE
OUT A FEW ISOLATED CELLS. HAVE INCLUDED A 20% AFTERNOON POP FOR A
BRIEF SHOWER AWAY FROM THE COAST FOR THE NORTHERN HALF OF THE
REGION...WHERE LAND/WATER DIFFERENCE IS LIKELY TO RESULT IN THE
STRONGEST SEA-BREEZE CIRCULATION. IF WE DO GET A FEW ISOLATED
SHOWERS...THEY WILL NOT LAST LONG AND SHOULD DISSIPATE QUICKLY AS
THE SUN BEGINS TO GET LOW IN THE SKY EARLY SATURDAY EVENING.
&&
.MID-LONG TERM (SATURDAY NIGHT-FRIDAY)...
CONTINUE TO EXPECT WEAK AND MAINLY DRY FRONT TO MOVE OVER THE REGION
SATURDAY NIGHT-SUNDAY WITH ONLY A SLIGHT CHANCE OF RAIN ASSOCIATED
WITH THE FRONT. DRIER HIGH PRESSURE QUICKLY BUILDS DOWN THE EASTERN
SEABOARD SLIGHTLY DROPPING TEMPERATURES LATER SUNDAY INTO EARLY NEXT
WEEK KEEPING TO AROUND SEASONAL NORMALS. RE-ENFORCING DOME OF HIGH
PRESSURE DROPPING OUT OF CANADA TO BUILD INTO THE REGION BY MID WEEK
KEEPING NORTHEASTERLY LOW LEVEL FLOW. MODELS DIFFER ON JUST HOW COLD
THIS AIRMASS IS BUT TEMPERATURES EXPECTED TO RUN AT LEAST SLIGHTLY
BELOW NORMAL TUE-FRI AREAWIDE.
&&
.AVIATION...
VFR CONDITIONS PREVAIL ACROSS THE REGION THIS AFTERNOON AND SHOULD
CONTINUE THROUGH THE EVENING HOURS. ALTHOUGH THE MOST WIDESPREAD
LOWER STRATUS AND FOG IS EXPECTED TO REMAIN TO THE NORTH OF THE
FORECAST TERMINALS...PATCHES OF LIGHT NIGHT / EARLY MORNING FOG ARE
STILL EXPECTED FURTHER SOUTH AWAY FROM THE IMMEDIATE COAST. HAVE
ADDED MVFR VIS TO THE TAFS FOR KLAL...KPGD...KFMY AND KRSW FOR A FEW
HOURS EARLY SATURDAY MORNING. THESE RESTRICTIONS SHOULD LIFT BY
14-15Z WITH VFR CONDITIONS THE REMAINDER OF THE DAY. WINDS WILL BE
LIGHT SATURDAY MORNING...BUT EXPECT A SHIFT OF WINDS TO A MODERATE
ONSHORE DIRECTION DURING THE AFTERNOON FOR KSRQ...KPIE...AND KTPA.
&&
.MARINE...
OFFSHORE GENTLE BREEZE WILL CONTINUE THROUGH TODAY IN THE EASTERN
GULF OF MEXICO AS HIGH PRESSURE REMAINS CENTERED NORTH OF THE
REGION. GRADIENT WINDS BEGIN TO RELAX BY TOMORROW AFTERNOON HELPING
A SEA BREEZE CIRCULATION SET UP NEAR THE COAST...HOWEVER NOT
EXPECTING ANY SHOWER OR THUNDERSTORM ACTIVITY OVER THE WATERS. A
WEAK AND RELATIVELY DRY COLD FRONT WILL PUSH THROUGH THE AREA ON
SUNDAY HELPING TO REINFORCE HIGH PRESSURE AND OFF SHORE WINDS. NO
SIGNIFICANT MARINE HEADLINES EXPECTED OVER THE WEEKEND.
&&
.FIRE WEATHER...
RELATIVE HUMIDITY WILL REMAIN ABOVE CRITICAL LEVELS THROUGH THE
WEEKEND. ONLY FIRE WEATHER CONCERN WOULD BE THE POTENTIAL FOR AREAS
OF LATE NIGHT AND EARLY MORNING FOG THROUGH SUNDAY MORNING. THE NEXT
COLD FRONT IS SCHEDULED TO ARRIVE DURING THE DAY ON SUNDAY. THIS
FRONT WILL PASS MAINLY DRY AND RESULT IN SOMEWHAT COOLER CONDITIONS
FOR THE EARLY PORTION OF NEXT WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 65 79 63 77 / 10 10 10 10
FMY 65 82 62 80 / 10 10 10 10
GIF 63 80 61 77 / 0 20 10 20
SRQ 64 78 61 76 / 10 0 10 10
BKV 61 80 55 77 / 0 20 10 10
SPG 66 78 64 76 / 10 10 10 10
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
SYNOPSIS/SHORT TERM/AVIATION/MARINE/FIRE WX...MROCZKA
MARINE...BARRON
LONG TERM...DAVIS
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
1050 AM EST FRI DEC 5 2014
.UPDATE (REST OF TODAY AND TONIGHT)...
15Z WATER VAPOR AND H4 RAP ANALYSIS CONTINUES TO SHOW AN UNAMPLIFIED
UPPER LEVEL PATTERN IN PLACE ACROSS THE CONUS. ONLY REAL FEATURE OF
NOTE IS A SHORTWAVE TROUGH EJECTING OUT OF THE SW STATES ACROSS THE
SOUTHERN PLAINS. THIS IMPULSE WILL CONTINUE EASTWARD TOWARD THE TN
VALLEY AND SOUTHEASTERN STATES FOR THE FIRST HALF OF THE WEEKEND...
BUT ALL SIGNIFICANT SENSIBLE WEATHER / SYNOPTIC FORCING FOR ASCENT
ASSOCIATED WITH THIS ENERGY IS STILL EXPECTED TO REMAIN TO THE NORTH
OF OUR FORECAST REGION. CURRENTLY THE UPPER LEVEL PATTERN OVER THE
EASTERN GULF AND FLORIDA PENINSULA IS ONE OF WEAK RIDGING. THIS
RIDGE WILL BE BROKEN DOWN OVER THE NEXT 24 HOURS AS THE SHORTWAVE
PASSES TO OUR NORTH...BUT ONCE AGAIN ANY SIGNIFICANT HEIGHT FALLS
WILL BE CONFINED TO AREAS WELL NORTH OF US. 05/12Z KTBW SOUNDING
PROFILE SHOWS A WELL DEFINED SUBSIDENCE INVERSION ASSOCIATED WITH
THE RIDGING ALOFT LOCATED AROUND 700MB WITH A FAIRLY MOIST COLUMN
BELOW THIS LEVEL...AND QUITE DRY COLUMN ABOVE. THE MOISTURE IN THE
LOWER LEVELS HAS BEEN ASSOCIATED WITH SCT-BKN CLOUDS THIS MORNING
BETWEEN 7-10KFT...WHICH SEEM TO BE STARTING TO BREAK UP AS WE
APPROACH MIDDAY. LUCKILY THERE WERE ENOUGH BREAKS IN THE CLOUDS
LOOKING EAST AS TO GIVE A DECENT VIEW FROM THE NWS OFFICE IN RUSKIN
OF THE ASCENDING ORION SPACECRAFT LIFTING OFF FROM THE CAPE
CANAVERAL. THE PW VALUE WAS CALCULATED AROUND 1.3"...WHICH DESPITE
THE DRIER COLUMN ALOFT IS STILL A BIT ABOVE CLIMATOLOGY FOR THE
FIRST WEEK OF DECEMBER.
AT THE SURFACE...LARGE HIGH PRESSURE SYSTEM RIDGES DOWN THE EASTERN
SEABOARD TO THE GULF OF MEXICO/FL PENINSULA PUTTING OUR REGION
WITHIN A SWATH OF EASTERLY LOW LEVEL SYNOPTIC FLOW.
REST OF TODAY...EXTENSIVE AREA OF LOWER CLOUDS/FOG OVER THE NORTHERN
PENINSULA IS SHOWING SIGNS OF RAPIDLY BURNING OFF NOW ON VISIBLE
IMAGERY...AND EXPECT SKIES TO BECOME PARTLY CLOUDY FOR ALL AREAS BY
MIDDAY. SIMILAR TO PREVIOUS DAYS...REGIONAL RADARS SHOWING A
SCATTERING OF SHOWERS/SPRINKLES MIGRATING WESTWARD FROM THE FL EAST
COAST INTO OUR SOME OF OUR EASTERN ZONES (POLK/HIGHLANDS). PAST
SEVERAL RUNS OF THE HRRR SUGGEST THIS ISOLATED/SCT LIGHT SHOWER
ACTIVITY WILL PERSIST INTO THE EARLY AFTERNOON AND EXPAND IN
COVERAGE FURTHER WEST AND SOUTH WITH TIME. WILL HAVE SLIGHT CHANCE
TO CHANCE POPS IN THE FORECAST...BUT DO NOT EXPECT THE SHOWERS TO BE
OF SIGNIFICANT IMPACT TO OUTDOOR ACTIVITIES THIS AFTERNOON.
TEMPERATURES ARE QUICKLY RISING THROUGH THE 70S...AND EXPECT MANY
LOCATIONS TO SEE HIGH TEMPERATURES UP NEAR 80 BY MID
AFTERNOON...LOWER 80S SOUTH OF THE I-4 CORRIDOR.
TONIGHT...SCT SHOWER/SPRINKLE ACTIVITY SHOULD DIMINISH EARLY
RESULTING IN A MOST DRY NIGHT FOR ALL. SREF GUIDANCE IS SUGGESTING
ONCE AGAIN THAT SOME FAIRLY WIDESPREAD STRATUS/FOG WILL DEVELOP
AFTER MIDNIGHT FOR OUR NORTHERN NATURE COAST ZONES....WITH MORE
PATCHY FOG DEVELOPING FURTHER SOUTH DOWN THE I-75 CORRIDOR. WILL
INCLUDE MENTION OF PATCHY FOG FOR ALL OVERNIGHT...WITH AREAS OF
DENSE FOG MENTIONED FOR CITRUS/LEVY COUNTIES. LOW TEMPERATURES BY
DAWN SATURDAY MORNING APPEAR SEASONABLE WITH A MOS BLEND RESULTING
IN UPPER 50S AROUND CHIEFLAND TO LOWER 60S AROUND
TAMPA/LAKELAND...AND LOWER/MID 60S FURTHER SOUTH.
HAVE A GREAT FRIDAY EVERYONE!
&&
.AVIATION...
AFTER SOME LOWER CLOUDS EARLY MORNING AROUND FORT MYERS...PREVAILING
VFR CONDITIONS HAVE RETURNED TO ALL TERMINALS AND SHOULD CONTINUE
THROUGH THE EVENING HOURS. PATCHY FOG IS EXPECTED ALONG THE I-75
CORRIDOR AFTER MIDNIGHT INTO EARLY SATURDAY MORNING...ALTHOUGH
WIDESPREAD CIG/VIS RESTRICTIONS BELOW IFR LEVELS IS CURRENTLY
ANTICIPATED TO REMAIN NORTH OF KTPA AND KLAL.
&&
.MARINE...
OFFSHORE GENTLE BREEZE WILL CONTINUE THROUGH TODAY IN THE EASTERN
GULF OF MEXICO AS HIGH PRESSURE REMAINS CENTERED NORTH OF THE
REGION. GRADIENT WINDS BEGIN TO RELAX BY TOMORROW AFTERNOON HELPING
A SEA BREEZE CIRCULATION SET UP NEAR THE COAST...HOWEVER NOT
EXPECTING ANY SHOWER OR THUNDERSTORM ACTIVITY OVER THE WATERS. A
WEAK AND RELATIVELY DRY COLD FRONT WILL PUSH THROUGH THE AREA ON
SUNDAY HELPING TO REINFORCE HIGH PRESSURE AND OFF SHORE WINDS. NO
SIGNIFICANT MARINE HEADLINES EXPECTED OVER THE WEEKEND.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 80 65 78 63 / 10 10 10 10
FMY 83 65 82 62 / 20 0 0 10
GIF 79 63 79 61 / 60 10 10 10
SRQ 82 63 79 61 / 10 10 0 10
BKV 79 60 80 55 / 20 10 10 10
SPG 78 66 78 64 / 10 10 10 10
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
UPDATE/AVIATION...MROCZKA
MARINE...BARRON
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
903 PM CST SAT DEC 6 2014
.SHORT TERM...
257 PM CST
NORTHEAST FLOW OVER THE REGION AHEAD OF HIGH PRESSURE HAS
CONTINUED TO EASE IN DRIER AIR. MID-AFTERNOON VISIBLE SATELLITE
IMAGERY REVEALS ONLY SOME DEPARTING STRATUS ACROSS THE FAR
SOUTHERN FORECAST AREA...AND SOME REMAINING RIBBONS OF LAKE EFFECT
CLOUDS INTO FAR NORTHEAST IL AND NORTHWEST IN. WATER VAPOR IMAGERY
CONFIRMS DRIER MID-LEVEL AIR AND SUPPRESSION MOVING OVERHEAD WHICH
SHOULD MITIGATE CLOUDS THIS EVENING...OUTSIDE OF A FEW LAKE
EFFECT CLOUDS INCHING WESTWARD OVER NORTHERN IL WITHIN THE
VEERING FLOW. A LIGHT WIND COMPONENT WILL REMAIN THIS EVENING
ALTHOUGH AS THE 1039 MB HIGH PASSES ACROSS WI...THE WINDS WILL
LIKELY BECOME LIGHT AND VARIABLE ALLOWING FOR FURTHER TEMPERATURE
DROP. DEW POINTS ARE SEVERAL DEGREES ABOVE THIS AT PRESENT...BUT
NOT REALLY A PATTERN WHERE WOULD EXPECT FOG...ESPECIALLY ANYTHING
OF NOTE.
SOUTHEAST WINDS WILL SETTLE IN ON SUNDAY WITH THE DEPARTING HIGH
AND LOW PRESSURE MARCHING EASTWARD NEAR THE NORTHERN CONUS BORDER.
HIGH CLOUDS LOOK TO GRADUALLY INCREASE/THICKEN DURING THE
AFTERNOON. GIVEN HIGHS TODAY REACHED THE UPPER 30S TO LOWER 40S
WOULD ENVISION SUNDAY BEING IN THE SAME ARENA IF CLOUDS DO NOT
THICKEN EARLIER THAN FORECAST.
MTF
&&
.LONG TERM...
315 PM CST
LONG TERM...SUNDAY NIGHT THROUGH SATURDAY...
OVERALL THE EXTENDED PERIOD WILL CONTINUE TO FEATURE A FAIRLY
PROGRESSIVE WEATHER PATTERN...WITH ONLY A QUICK HIT OF SOME COLDER
AIR FOR LATE TUESDAY INTO WEDNESDAY. THE MAIN FORECAST CONCERNS
DURING THE PERIOD WILL BE THE INCREASING POTENTIAL OF A QUICK HIT OF
WINTERY WEATHER LATE SUNDAY NIGHT INTO MONDAY MORNING.
WATER VAPOR IMAGERY INDICATES THE NEXT PACIFIC SYSTEM OF
INTEREST...NOW SHIFTING ONSHORE ACROSS WASHINGTON STATE. THIS
FEATURE...ALONG WITH AN ASSOCIATED AREA OF LOW PRESSURE IS EXPECTED
TO TRACK QUICKLY ALONG OR NEAR THE CANADIAN INTERNATIONAL
BORDER SUNDAY THROUGH TUESDAY. TYPICALLY THIS TYPE OF TRACK IS NOT
GOOD FOR MUCH PRECIPITATION FOR THE AREA...AND OVERALL THIS WILL BE
THE CASE. HOWEVER...IT APPEARS THAT QUICK HIT OF WINTRY PRECIPITATION
IS LIKELY LATE SUNDAY NIGHT INTO EARLY MONDAY MORNING.
A PERIOD OF INCREASING ISENTROPIC ASCENT COMBINED WITH SOME DECENT
Q-VECTOR CONVERGENCE...ASSOCIATED WITH ADDITIONAL SHORTWAVE ENERGY
DIGGING SOUTHEASTWARD TOWARDS THAT AREA LATER SUNDAY NIGHT...SHOULD
PROVIDE A SHORT PERIOD OF FORCING SUPPORTIVE OF PRECIPITATION ACROSS
NORTHERN ILLINOIS/NORTHWESTERN INDIANA. OVERALL...THIS STILL APPEARS
TO BE A SMALL EVENT FOR THE AREA. HOWEVER...IT APPEARS THAT A
STRENGTHENING BAROCLINIC ZONE ALONG AN OCCLUDED FRONTAL BOUNDARY MAY
PROVIDE A SHORT PERIOD OF ENHANCED MESOSCALE FORCING...SUPPORTIVE A
SHORT PERIOD OF HEAVIER PRECIPITATION...ESPECIALLY GIVEN THE PRESENCE
OF STEEP MID LEVEL LAPSE RATES INTO MONDAY MORNING. THUS...IT
APPEARS THAT BAND OF PRECIPITATION...POSSIBLY ONLY LASTING A COUPLE
HOURS AT ANY GIVEN LOCATION...IS LIKELY TO MOVE ACROSS THE AREA IN
TIME FOR THE MONDAY MORNING RUSH.
PRECIP TYPE STILL APPEARS TO BE TRICKY WITH THIS ACTIVITY EARLY
MONDAY. ASIDE FOR THE NAM SOLUTION...MOST MODEL DERIVED SOUNDINGS
ACROSS NORTHERN ILLINOIS INDICATE MAX LAYER TEMPERATURES OF ONLY +1
TO +1.5 DEGREES CELSIUS...WHICH WOULD SUGGEST ONLY PARTIAL MELTING OF
DENDRITES...POSSIBLY RESULTING IN SNOW AND SLEET PRECIP TYPES ACROSS
MOST OF FAR NORTHERN ILLINOIS. ALSO...GIVEN THAT THERE COULD BE SOME
ENHANCE PRECIP RATES WITH THIS ACTIVITY...AS WELL AS THE FACT THAT
EVAPORATIVE COOLING POTENTIAL SUNDAY NIGHT WILL BE HIGH...IT APPEARS
PRUDENT TO MENTION MORE OF A SNOW AND SLEET SCENARIO ACROSS FAR
NORTHERN ILLINOIS RATHER THAN FREEZING RAIN AT THIS POINT. THEREFORE...I
HAVE TRENDED THE FORECAST IN THIS DIRECTION.
ACCUMULATIONS ARE ALSO POSSIBLE WITH THIS ACTIVITY. IN FACT...SOME
AREAS COULD GET A QUICK INCH OF SNOW...IF IT FALLS PRIMARILY AS SUCH.
AT THIS TIME IT APPEARS THE BEST POTENTIAL FOR THIS APPEARS TO BE
ROUGHLY ALONG AND NORTH OF I-88 IN NORTHERN ILLINOIS. ALTHOUGH TOTAL
AMOUNTS WILL BE LIGHT...THE POSSIBILITY OF A QUICK HALF TO ONE INCH OF
SNOW RIGHT AROUND DAYBREAK MONDAY COULD CAUSE PROBLEMS FOR THE
MONDAY MORNING COMMUTE. AREAS SOUTH OF INTERSTATE 80 COULD SEE MORE
OF MIX BAG OF RAIN...FREEZING RAIN...SLEET AND SNOW GIVEN SLIGHTLY
WARMER MID LEVEL TEMPERATURES. SURFACE TEMPERATURES HERE MAY BE
HOVERING RIGHT AROUND FREEZING...SO QUESTIONS STILL RESIDE AROUND
HOW MUCH OF THIS PRECIP WILL BE FROZEN.
ONCE THIS BAND OF HEAVER PRECIP SHIFTS EAST OF THE AREA BY LATE
MORNING...IT APPEARS THAT THE MID LEVELS WILL DRY OUT
SUBSTANTIALLY...THUS ANY LINGERING PRECIP MONDAY AFTERNOON WOULD
LIKELY BE MORE DRIZZLY. THE COLDER SIDE OF THE STORM SYSTEM WILL
ARRIVE ACROSS THE REGION BY EARLY MONDAY EVENING...AS WINDS BECOME A
BIT GUSTY OUT OF THE WEST NORTHWEST. THIS SHOULD RESULT IN A COLDER
DAY ACROSS THE AREA ON TUESDAY. MOST AREAS WILL REMAIN DRY TUESDAY
AND TUESDAY NIGHT. HOWEVER...SOME LAKE EFFECT SNOW SHOWERS OR
FLURRIES ARE POSSIBLE ACROSS NORTHWESTERN INDIANA DURING THE DAY
TUESDAY. THEN AS THE LOWER LEVEL FLOW VEERS MORE NORTHERLY LATE
TUESDAY THESE LAKE EFFECT FLURRIES COULD GET INTO NORTHEASTERN
ILLINOIS TUESDAY EVENING. OVERALL...THIS DOES NOT APPEAR TO BE MUCH
OF A LAKE EFFECT EVENT AS LAKE INDUCED INVERSION HEIGHTS DO NOT
APPEAR VERY IMPRESSIVE...AND EVEN APPEAR TO REMAIN BELOW THE DENDRITIC
GROWTH ZONE.
THE WEATHER THE REST OF THE WEEK APPEARS TO BE FAIRLY QUIT...BUT ON
A WARMING TREND. MID LEVEL HEIGHT RISES ARE EXPECTED TO OVERSPREAD
MUCH OF THE CENTRAL CONUS LATER IN THE PERIOD IN RESPONSE TO THE
PERSISTENT NEGATIVE HEIGHT ANOMALIES ACROSS THE NORTHEASTERN PACIFIC
AND GULF OF ALASKA REGION SHIFTING EASTWARD TOWARDS THE WESTERN
NORTH AMERICAN COAST. THIS PARTICULARLY PATTERN STILL LOOKS TO BE
CONDUCE FOR A PERIOD OF MUCH ABOVE NORMAL TEMPERATURES NEXT FRIDAY
AND ESPECIALLY INTO SATURDAY. MODEL GUIDANCE HAS BEEN IN GOOD
AGREEMENT IN INDICATING THIS LARGER SCALE EL NINO-LIKE PATTERN
EVOLVING...AND GIVEN THAT THIS IS PATTERN KNOWN FOR PRODUCING MILD
CONDITIONS LOCALLY...CONFIDENCE IS ABOVE AVERAGE FOR THIS PERIOD TO
EXPERIENCE ABOVE AVERAGE TEMPERATURES. AT THIS TIME I HAVE REMAINED
A BIT CONSERVATIVE ON TEMPERATURES...ONLY WARMING THEM TO NEAR 50 FOR
SATURDAY. THIS COULD BE SEVERAL DEGREES TOO LOW IF THE CURRENT MODEL
FORECASTS PAN OUT. MOST GUIDANCE IS INDICATING 925 MB TEMPERATURES
ANYWHERE FROM +6 TO +10 DEGREES CELSIUS...WHICH COULD SUPPORT
TEMPERATURES INTO THE 50S BY NEXT SATURDAY UNDER A 570+ DM MID LEVEL
RIDGE.
KJB
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 03Z...
* NORTH-NORTHEAST WINDS DIMINISHING THIS EVENING...THEN BECOMING
EAST-SOUTHEAST EARLY SUNDAY. SOUTHEAST WIND AROUND 10 KT FROM
LATE MORNING SUNDAY ON.
RATZER
//DISCUSSION...UPDATED 00Z...
HIGH PRESSURE WAS BUILDING SOUTHEAST ACROSS THE UPPER MIDWEST AND
GREAT LAKES REGION EARLY THIS EVENING...WITH CLEARING SKIES AND
DIMINISHING NORTH-NORTHEAST WINDS THIS EVENING EVENTUALLY
BECOMING EAST-SOUTHEAST BY EARLY SUNDAY. LOW LEVEL FLOW OFF OF
LAKE MICHIGAN HAS MAINTAINED A THIN BROKEN MVFR STRATOCUMULUS
CLOUD DECK AROUND 2500 FT ACROSS ORD-MDW AND GYY TERMINALS...
AND CURRENT IR SATELLITE IMAGERY AND FORECAST SOUNDING PROFILES
INDICATE THAT THIS WILL CONTINUE FOR THE NEXT 1-2 HOURS BEFORE
SKIES COMPLETELY CLEAR BENEATH LOWERING SUBSIDENCE INVERSION
ASSOCIATED WITH THE APPROACHING SURFACE HIGH.
THE CENTER OF THE HIGH WILL PASS NORTH OF THE AREA EARLY SUNDAY
MORNING ALLOWING WINDS TO GRADUALLY SHIFT TO THE EAST-SOUTHEAST
AND EVENTUALLY SOUTHEAST ON SUNDAY. SPEEDS WILL INCREASE TO RIGHT
AROUND 10 KTS BY LATE MORNING AND CONTINUE INTO SUNDAY NIGHT IN
RESPONSE TO A WEATHER DISTURBANCE TRACKING ACROSS THE NORTHERN
PLAINS AND UPPER MIDWEST. LOW LEVELS LOOK TO REMAIN QUITE DRY
THROUGH SUNDAY EVENING...WHILE VFR HIGH CLOUDS THICKEN AND LOWER
WITH TIME. EVENTUALLY...PRECIPITATION IN THE FORM OF SNOW AND/OR
SLEET AND MVFR/BRIEF IFR CONDITIONS WILL LIKELY DEVELOP BEYOND
THE END OF THE CURRENT TAF PERIOD EARLY MONDAY MORNING.
RATZER
//ORD AND MDW CONFIDENCE...UPDATED 03Z...
* HIGH CONFIDENCE ALL OTHER ELEMENTS.
RATZER
//OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z...
MONDAY...CHANCE OF SLEET/SNOW MIX IN THE MORNING. MVFR/BRIEF IFR
POSSIBLE. S WINDS BECOMING W.
TUESDAY...VFR. NW WINDS BECOMING N.
WEDNESDAY...VFR. N WINDS BECOMING NE.
THURSDAY...VFR. S WINDS.
FRIDAY...VFR. S WINDS.
RATZER
&&
.MARINE...
222 PM CST
TONIGHT THROUGH SUNDAY
THE STIFF NORTHERLY WINDS ACROSS THE LAKE TODAY WILL EASE THIS
EVENING AND VEER EASTWARD BY OVERNIGHT. WAVES WILL SUBSIDE BELOW 5
FT BY LATE TONIGHT. THE PROGRESSIVE PATTERN CONTINUES WITH HIGH
PRESSURE ADVANCING OVER THE LAKE QUICKLY OVERNIGHT FOLLOWED BY
INFLUENCE OF APPROACHING LOW PRESSURE ALREADY BY SUNDAY WITH WINDS
TURNING SOUTHEASTERLY.
SUNDAY NIGHT ONWARD
STRONG HIGH PRESSURE SHIFTING EASTWARD FROM QUEBEC AND WEAK LOW
PRESSURE TRACKING EAST ALONG THE CANADIAN BORDER WILL REALLY TIGHTEN
THE PRESSURE GRADIENT AND CAUSE SOUTHEAST WINDS TO TURN SOUTH AND
STRENGTHEN ON SUNDAY NIGHT INTO MONDAY MORNING. LOOKING AT GUSTS
PRIMARILY UP TO 25 TO 30 KT OVER THE OPEN WATERS...BUT COULD SEE A
FEW GALE FORCE GUSTS ON NORTH HALF. COLD FRONT TRAILING FROM THE
WEAK LOW PRESSURE WILL CROSS THE LAKE MONDAY EVENING AND
NIGHT...FOLLOWED BY ANOTHER EXPANSIVE HIGH PRESSURE. WINDS WILL TURN
WEST-NORTHWEST MONDAY NIGHT TO NORTHERLY BY TUESDAY MORNING.
CURRENTLY EXPECTING SPEEDS/GUSTS UP TO 30 KT LATE MONDAY NIGHT
THROUGH TUESDAY...BUT AGAIN CANNOT RULE OUT A PERIOD OF GALES ON THE
NORTH TUESDAY MORNING WHEN PRESSURE RISES MAXIMIZE. NORTHERLY WINDS
WILL GRADUALLY DIMINISH ON TUESDAY NIGHT INTO WEDNESDAY AS THE HIGH
TRAVERSES THE LAKE...SHIFTING TO SOUTHWEST ON THURSDAY INTO THURSDAY
NIGHT ON THE BACK SIDE OF THE HIGH.
FOR THE NEARSHORE WATERS...SMALL CRAFT ADVISORY CRITERIA IS POSSIBLE
SUNDAY NIGHT INTO MONDAY MORNING...ESPECIALLY FOR THE ILLINOIS
SHORE. SMALL CRAFT CONDITIONS ARE THEN LIKELY TUESDAY MORNING INTO
WEDNESDAY.
MTF/RC
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 3 AM SUNDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
[top]
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
828 PM CST Sat Dec 6 2014
.UPDATE...
ISSUED AT 822 PM CST SAT DEC 6 2014
The low clouds that plagued our area all day long have cleared all
but our far south and southeast counties this evening. However,
a large band of cirrus was streaming east into our area and will
be with us overnight and into most of Sunday. Temperatures for the
first few hours after skies cleared fell rapidly across the north
but have since steadied out some as the high level cloud cover
overspread the area. The latest surface map has a large area of
high pressure over central Wisconsin which is expected to push
east across the central Great Lakes over the next 24 hours keeping
our weather quiet. Have already sent out an update to address the
overnight temperatures across the north, with the remainder of
the forecast in good shape this evening.
&&
.SHORT TERM...(Tonight)
ISSUED AT 308 PM CST SAT DEC 6 2014
Clearing trend has finally started to make some headway southward
this afternoon, with the edge of the stratocumulus deck generally
along a Macomb to Peoria to Pontiac line at 230 pm. AWIPS timing
tool would suggest a position along I-72 in the 530-6 pm time frame,
while the HRRR is a bit slower around 8 pm. Additional erosion from
the northeast is indicated by the HRRR late evening, although at the
same time cirrus clouds will be streaming east from the Plains.
Thus, have mainly gone with a partly cloudy sky for tonight`s
forecast.
North/northeast flow to prevail into tonight, as high pressure
currently over Lake Superior settles southeast across the Great
Lakes. Temperatures expected to drop into the mid to upper 20s
overnight.
&&
.LONG TERM...(Sunday through Saturday)
ISSUED AT 308 PM CST SAT DEC 6 2014
High pressure will shift eastward from Illinois Sunday as a clipper
system approaches from the WNW. This system will start bringing
increasingly thick high clouds through the day Sunday, but the air
mass will generally remain quite dry in a layer from around 2000 to
12000 feet. This dry layer will take some time to saturate
overnight, which means only a slight chance for precipitation NW of
the Illinois River before midnight. These layers will saturate
through the night allowing a better chance for precipitation
reaching the surface mainly during the morning. Dry air will start
to move in aloft during the day Monday as the system shifts east of
the area, ending deep enough saturation for precipitation processes
to take place. Precipitation type looks to be largely rain for
central Illinois given a deep warm layer just off the surface. Still
some chance for light freezing rain with temperatures hovering very
near the freezing mark at the surface. Farther to the north, the
warm layer off the surface is less pronounced, which could allow for
snow or a mix of rain and snow to reach the surface..
A high pressure ridge will develop over the plains for much of the
week with NW flow and dry conditions for central IL. Temperatures
will remain below normal for much of the week as a result. Friday
and Saturday may see a substantial warmup as the plains ridge shifts
over IL. Only chance for precipitation in the extended forecast at
this time appears to be around Friday morning as a few models hint
at a weak disturbance meandering through the region at this time.
&&
.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
ISSUED AT 500 PM CST SAT DEC 6 2014
MVFR and IFR cigs slowly shifting south early this evening and at
the same time, a large area of cirrus clouds was streaking east into
our area. A band of moisture/clouds (MVFR) was also seen over northeast
Illinois coming off of Lake Michigan and was tracking southwest and
may affect BMI and CMI in the 01z to 03z time frame. Short term high
resolution models continue to push the low clouds south over the next
several hours reaching SPI and DEC by around 02z. These two sites look
to be the pivot point with respect to their eventual movement later
tonight with models suggesting more of a southwest to west track as
high pressure shifts over the central Great Lakes and our flow becomes
more northeast to east. Once we do lose the MVFR cigs, it appears we
will have to deal with the mid and high level (VFR) cigs late tonight
and into Sunday. Surface winds will be northeast to east at 5 to
10 kts tonight with winds becoming east to southeast at 10 to 15 kts
on Sunday.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Smith
SHORT TERM...Geelhart
LONG TERM...Onton
AVIATION...Smith
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
546 PM CST SAT DEC 6 2014
.SHORT TERM...
257 PM CST
NORTHEAST FLOW OVER THE REGION AHEAD OF HIGH PRESSURE HAS
CONTINUED TO EASE IN DRIER AIR. MID-AFTERNOON VISIBLE SATELLITE
IMAGERY REVEALS ONLY SOME DEPARTING STRATUS ACROSS THE FAR
SOUTHERN FORECAST AREA...AND SOME REMAINING RIBBONS OF LAKE EFFECT
CLOUDS INTO FAR NORTHEAST IL AND NORTHWEST IN. WATER VAPOR IMAGERY
CONFIRMS DRIER MID-LEVEL AIR AND SUPPRESSION MOVING OVERHEAD WHICH
SHOULD MITIGATE CLOUDS THIS EVENING...OUTSIDE OF A FEW LAKE
EFFECT CLOUDS INCHING WESTWARD OVER NORTHERN IL WITHIN THE
VEERING FLOW. A LIGHT WIND COMPONENT WILL REMAIN THIS EVENING
ALTHOUGH AS THE 1039 MB HIGH PASSES ACROSS WI...THE WINDS WILL
LIKELY BECOME LIGHT AND VARIABLE ALLOWING FOR FURTHER TEMPERATURE
DROP. DEW POINTS ARE SEVERAL DEGREES ABOVE THIS AT PRESENT...BUT
NOT REALLY A PATTERN WHERE WOULD EXPECT FOG...ESPECIALLY ANYTHING
OF NOTE.
SOUTHEAST WINDS WILL SETTLE IN ON SUNDAY WITH THE DEPARTING HIGH
AND LOW PRESSURE MARCHING EASTWARD NEAR THE NORTHERN CONUS BORDER.
HIGH CLOUDS LOOK TO GRADUALLY INCREASE/THICKEN DURING THE
AFTERNOON. GIVEN HIGHS TODAY REACHED THE UPPER 30S TO LOWER 40S
WOULD ENVISION SUNDAY BEING IN THE SAME ARENA IF CLOUDS DO NOT
THICKEN EARLIER THAN FORECAST.
MTF
&&
.LONG TERM...
315 PM CST
LONG TERM...SUNDAY NIGHT THROUGH SATURDAY...
OVERALL THE EXTENDED PERIOD WILL CONTINUE TO FEATURE A FAIRLY
PROGRESSIVE WEATHER PATTERN...WITH ONLY A QUICK HIT OF SOME COLDER
AIR FOR LATE TUESDAY INTO WEDNESDAY. THE MAIN FORECAST CONCERNS
DURING THE PERIOD WILL BE THE INCREASING POTENTIAL OF A QUICK HIT OF
WINTERY WEATHER LATE SUNDAY NIGHT INTO MONDAY MORNING.
WATER VAPOR IMAGERY INDICATES THE NEXT PACIFIC SYSTEM OF
INTEREST...NOW SHIFTING ONSHORE ACROSS WASHINGTON STATE. THIS
FEATURE...ALONG WITH AN ASSOCIATED AREA OF LOW PRESSURE IS EXPECTED
TO TRACK QUICKLY ALONG OR NEAR THE CANADIAN INTERNATIONAL
BORDER SUNDAY THROUGH TUESDAY. TYPICALLY THIS TYPE OF TRACK IS NOT
GOOD FOR MUCH PRECIPITATION FOR THE AREA...AND OVERALL THIS WILL BE
THE CASE. HOWEVER...IT APPEARS THAT QUICK HIT OF WINTRY PRECIPITATION
IS LIKELY LATE SUNDAY NIGHT INTO EARLY MONDAY MORNING.
A PERIOD OF INCREASING ISENTROPIC ASCENT COMBINED WITH SOME DECENT
Q-VECTOR CONVERGENCE...ASSOCIATED WITH ADDITIONAL SHORTWAVE ENERGY
DIGGING SOUTHEASTWARD TOWARDS THAT AREA LATER SUNDAY NIGHT...SHOULD
PROVIDE A SHORT PERIOD OF FORCING SUPPORTIVE OF PRECIPITATION ACROSS
NORTHERN ILLINOIS/NORTHWESTERN INDIANA. OVERALL...THIS STILL APPEARS
TO BE A SMALL EVENT FOR THE AREA. HOWEVER...IT APPEARS THAT A
STRENGTHENING BAROCLINIC ZONE ALONG AN OCCLUDED FRONTAL BOUNDARY MAY
PROVIDE A SHORT PERIOD OF ENHANCED MESOSCALE FORCING...SUPPORTIVE A
SHORT PERIOD OF HEAVIER PRECIPITATION...ESPECIALLY GIVEN THE PRESENCE
OF STEEP MID LEVEL LAPSE RATES INTO MONDAY MORNING. THUS...IT
APPEARS THAT BAND OF PRECIPITATION...POSSIBLY ONLY LASTING A COUPLE
HOURS AT ANY GIVEN LOCATION...IS LIKELY TO MOVE ACROSS THE AREA IN
TIME FOR THE MONDAY MORNING RUSH.
PRECIP TYPE STILL APPEARS TO BE TRICKY WITH THIS ACTIVITY EARLY
MONDAY. ASIDE FOR THE NAM SOLUTION...MOST MODEL DERIVED SOUNDINGS
ACROSS NORTHERN ILLINOIS INDICATE MAX LAYER TEMPERATURES OF ONLY +1
TO +1.5 DEGREES CELSIUS...WHICH WOULD SUGGEST ONLY PARTIAL MELTING OF
DENDRITES...POSSIBLY RESULTING IN SNOW AND SLEET PRECIP TYPES ACROSS
MOST OF FAR NORTHERN ILLINOIS. ALSO...GIVEN THAT THERE COULD BE SOME
ENHANCE PRECIP RATES WITH THIS ACTIVITY...AS WELL AS THE FACT THAT
EVAPORATIVE COOLING POTENTIAL SUNDAY NIGHT WILL BE HIGH...IT APPEARS
PRUDENT TO MENTION MORE OF A SNOW AND SLEET SCENARIO ACROSS FAR
NORTHERN ILLINOIS RATHER THAN FREEZING RAIN AT THIS POINT. THEREFORE...I
HAVE TRENDED THE FORECAST IN THIS DIRECTION.
ACCUMULATIONS ARE ALSO POSSIBLE WITH THIS ACTIVITY. IN FACT...SOME
AREAS COULD GET A QUICK INCH OF SNOW...IF IT FALLS PRIMARILY AS SUCH.
AT THIS TIME IT APPEARS THE BEST POTENTIAL FOR THIS APPEARS TO BE
ROUGHLY ALONG AND NORTH OF I-88 IN NORTHERN ILLINOIS. ALTHOUGH TOTAL
AMOUNTS WILL BE LIGHT...THE POSSIBILITY OF A QUICK HALF TO ONE INCH OF
SNOW RIGHT AROUND DAYBREAK MONDAY COULD CAUSE PROBLEMS FOR THE
MONDAY MORNING COMMUTE. AREAS SOUTH OF INTERSTATE 80 COULD SEE MORE
OF MIX BAG OF RAIN...FREEZING RAIN...SLEET AND SNOW GIVEN SLIGHTLY
WARMER MID LEVEL TEMPERATURES. SURFACE TEMPERATURES HERE MAY BE
HOVERING RIGHT AROUND FREEZING...SO QUESTIONS STILL RESIDE AROUND
HOW MUCH OF THIS PRECIP WILL BE FROZEN.
ONCE THIS BAND OF HEAVER PRECIP SHIFTS EAST OF THE AREA BY LATE
MORNING...IT APPEARS THAT THE MID LEVELS WILL DRY OUT
SUBSTANTIALLY...THUS ANY LINGERING PRECIP MONDAY AFTERNOON WOULD
LIKELY BE MORE DRIZZLY. THE COLDER SIDE OF THE STORM SYSTEM WILL
ARRIVE ACROSS THE REGION BY EARLY MONDAY EVENING...AS WINDS BECOME A
BIT GUSTY OUT OF THE WEST NORTHWEST. THIS SHOULD RESULT IN A COLDER
DAY ACROSS THE AREA ON TUESDAY. MOST AREAS WILL REMAIN DRY TUESDAY
AND TUESDAY NIGHT. HOWEVER...SOME LAKE EFFECT SNOW SHOWERS OR
FLURRIES ARE POSSIBLE ACROSS NORTHWESTERN INDIANA DURING THE DAY
TUESDAY. THEN AS THE LOWER LEVEL FLOW VEERS MORE NORTHERLY LATE
TUESDAY THESE LAKE EFFECT FLURRIES COULD GET INTO NORTHEASTERN
ILLINOIS TUESDAY EVENING. OVERALL...THIS DOES NOT APPEAR TO BE MUCH
OF A LAKE EFFECT EVENT AS LAKE INDUCED INVERSION HEIGHTS DO NOT
APPEAR VERY IMPRESSIVE...AND EVEN APPEAR TO REMAIN BELOW THE DENDRITIC
GROWTH ZONE.
THE WEATHER THE REST OF THE WEEK APPEARS TO BE FAIRLY QUIT...BUT ON
A WARMING TREND. MID LEVEL HEIGHT RISES ARE EXPECTED TO OVERSPREAD
MUCH OF THE CENTRAL CONUS LATER IN THE PERIOD IN RESPONSE TO THE
PERSISTENT NEGATIVE HEIGHT ANOMALIES ACROSS THE NORTHEASTERN PACIFIC
AND GULF OF ALASKA REGION SHIFTING EASTWARD TOWARDS THE WESTERN
NORTH AMERICAN COAST. THIS PARTICULARLY PATTERN STILL LOOKS TO BE
CONDUCE FOR A PERIOD OF MUCH ABOVE NORMAL TEMPERATURES NEXT FRIDAY
AND ESPECIALLY INTO SATURDAY. MODEL GUIDANCE HAS BEEN IN GOOD
AGREEMENT IN INDICATING THIS LARGER SCALE EL NINO-LIKE PATTERN
EVOLVING...AND GIVEN THAT THIS IS PATTERN KNOWN FOR PRODUCING MILD
CONDITIONS LOCALLY...CONFIDENCE IS ABOVE AVERAGE FOR THIS PERIOD TO
EXPERIENCE ABOVE AVERAGE TEMPERATURES. AT THIS TIME I HAVE REMAINED
A BIT CONSERVATIVE ON TEMPERATURES...ONLY WARMING THEM TO NEAR 50 FOR
SATURDAY. THIS COULD BE SEVERAL DEGREES TOO LOW IF THE CURRENT MODEL
FORECASTS PAN OUT. MOST GUIDANCE IS INDICATING 925 MB TEMPERATURES
ANYWHERE FROM +6 TO +10 DEGREES CELSIUS...WHICH COULD SUPPORT
TEMPERATURES INTO THE 50S BY NEXT SATURDAY UNDER A 570+ DM MID LEVEL
RIDGE.
KJB
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 00Z...
* BRIEF PERIOD OF MVFR CIG AROUND 2500 FT EARLY THIS EVENING.
* NORTH-NORTHEAST WINDS DIMINISHING THIS EVENING...THEN BECOMING
EAST-SOUTHEAST EARLY SUNDAY. SOUTHEAST WIND AROUND 10 KT FROM
LATE MORNING SUNDAY ON.
RATZER
//DISCUSSION...UPDATED 00Z...
HIGH PRESSURE WAS BUILDING SOUTHEAST ACROSS THE UPPER MIDWEST AND
GREAT LAKES REGION EARLY THIS EVENING...WITH CLEARING SKIES AND
DIMINISHING NORTH-NORTHEAST WINDS THIS EVENING EVENTUALLY
BECOMING EAST-SOUTHEAST BY EARLY SUNDAY. LOW LEVEL FLOW OFF OF
LAKE MICHIGAN HAS MAINTAINED A THIN BROKEN MVFR STRATOCUMULUS
CLOUD DECK AROUND 2500 FT ACROSS ORD-MDW AND GYY TERMINALS...
AND CURRENT IR SATELLITE IMAGERY AND FORECAST SOUNDING PROFILES
INDICATE THAT THIS WILL CONTINUE FOR THE NEXT 1-2 HOURS BEFORE
SKIES COMPLETELY CLEAR BENEATH LOWERING SUBSIDENCE INVERSION
ASSOCIATED WITH THE APPROACHING SURFACE HIGH.
THE CENTER OF THE HIGH WILL PASS NORTH OF THE AREA EARLY SUNDAY
MORNING ALLOWING WINDS TO GRADUALLY SHIFT TO THE EAST-SOUTHEAST
AND EVENTUALLY SOUTHEAST ON SUNDAY. SPEEDS WILL INCREASE TO RIGHT
AROUND 10 KTS BY LATE MORNING AND CONTINUE INTO SUNDAY NIGHT IN
RESPONSE TO A WEATHER DISTURBANCE TRACKING ACROSS THE NORTHERN
PLAINS AND UPPER MIDWEST. LOW LEVELS LOOK TO REMAIN QUITE DRY
THROUGH SUNDAY EVENING...WHILE VFR HIGH CLOUDS THICKEN AND LOWER
WITH TIME. EVENTUALLY...PRECIPITATION IN THE FORM OF SNOW AND/OR
SLEET AND MVFR/BRIEF IFR CONDITIONS WILL LIKELY DEVELOP BEYOND
THE END OF THE CURRENT TAF PERIOD EARLY MONDAY MORNING.
RATZER
//ORD AND MDW CONFIDENCE...UPDATED 00Z...
* MEDIUM-HIGH CONFIDENCE IN TIMING OF BRIEF MVFR STRATOCU OFF LAKE
EARLY THIS EVENING.
* HIGH CONFIDENCE ALL OTHER ELEMENTS.
RATZER
//OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z...
MONDAY...CHANCE OF SLEET/SNOW MIX IN THE MORNING. MVFR/BRIEF IFR
POSSIBLE. S WINDS BECOMING W.
TUESDAY...VFR. NW WINDS BECOMING N.
WEDNESDAY...VFR. N WINDS BECOMING NE.
THURSDAY...VFR. S WINDS.
FRIDAY...VFR. S WINDS.
RATZER
&&
.MARINE...
222 PM CST
TONIGHT THROUGH SUNDAY
THE STIFF NORTHERLY WINDS ACROSS THE LAKE TODAY WILL EASE THIS
EVENING AND VEER EASTWARD BY OVERNIGHT. WAVES WILL SUBSIDE BELOW 5
FT BY LATE TONIGHT. THE PROGRESSIVE PATTERN CONTINUES WITH HIGH
PRESSURE ADVANCING OVER THE LAKE QUICKLY OVERNIGHT FOLLOWED BY
INFLUENCE OF APPROACHING LOW PRESSURE ALREADY BY SUNDAY WITH WINDS
TURNING SOUTHEASTERLY.
SUNDAY NIGHT ONWARD
STRONG HIGH PRESSURE SHIFTING EASTWARD FROM QUEBEC AND WEAK LOW
PRESSURE TRACKING EAST ALONG THE CANADIAN BORDER WILL REALLY TIGHTEN
THE PRESSURE GRADIENT AND CAUSE SOUTHEAST WINDS TO TURN SOUTH AND
STRENGTHEN ON SUNDAY NIGHT INTO MONDAY MORNING. LOOKING AT GUSTS
PRIMARILY UP TO 25 TO 30 KT OVER THE OPEN WATERS...BUT COULD SEE A
FEW GALE FORCE GUSTS ON NORTH HALF. COLD FRONT TRAILING FROM THE
WEAK LOW PRESSURE WILL CROSS THE LAKE MONDAY EVENING AND
NIGHT...FOLLOWED BY ANOTHER EXPANSIVE HIGH PRESSURE. WINDS WILL TURN
WEST-NORTHWEST MONDAY NIGHT TO NORTHERLY BY TUESDAY MORNING.
CURRENTLY EXPECTING SPEEDS/GUSTS UP TO 30 KT LATE MONDAY NIGHT
THROUGH TUESDAY...BUT AGAIN CANNOT RULE OUT A PERIOD OF GALES ON THE
NORTH TUESDAY MORNING WHEN PRESSURE RISES MAXIMIZE. NORTHERLY WINDS
WILL GRADUALLY DIMINISH ON TUESDAY NIGHT INTO WEDNESDAY AS THE HIGH
TRAVERSES THE LAKE...SHIFTING TO SOUTHWEST ON THURSDAY INTO THURSDAY
NIGHT ON THE BACK SIDE OF THE HIGH.
FOR THE NEARSHORE WATERS...SMALL CRAFT ADVISORY CRITERIA IS POSSIBLE
SUNDAY NIGHT INTO MONDAY MORNING...ESPECIALLY FOR THE ILLINOIS
SHORE. SMALL CRAFT CONDITIONS ARE THEN LIKELY TUESDAY MORNING INTO
WEDNESDAY.
MTF/RC
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 3 AM SUNDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
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Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
503 PM CST Sat Dec 6 2014
.SHORT TERM...(Tonight)
ISSUED AT 308 PM CST SAT DEC 6 2014
Clearing trend has finally started to make some headway southward
this afternoon, with the edge of the stratocumulus deck generally
along a Macomb to Peoria to Pontiac line at 230 pm. AWIPS timing
tool would suggest a position along I-72 in the 530-6 pm time frame,
while the HRRR is a bit slower around 8 pm. Additional erosion from
the northeast is indicated by the HRRR late evening, although at the
same time cirrus clouds will be streaming east from the Plains.
Thus, have mainly gone with a partly cloudy sky for tonight`s
forecast.
North/northeast flow to prevail into tonight, as high pressure
currently over Lake Superior settles southeast across the Great
Lakes. Temperatures expected to drop into the mid to upper 20s
overnight.
&&
.LONG TERM...(Sunday through Saturday)
ISSUED AT 308 PM CST SAT DEC 6 2014
High pressure will shift eastward from Illinois Sunday as a clipper
system approaches from the WNW. This system will start bringing
increasingly thick high clouds through the day Sunday, but the air
mass will generally remain quite dry in a layer from around 2000 to
12000 feet. This dry layer will take some time to saturate
overnight, which means only a slight chance for precipitation NW of
the Illinois River before midnight. These layers will saturate
through the night allowing a better chance for precipitation
reaching the surface mainly during the morning. Dry air will start
to move in aloft during the day Monday as the system shifts east of
the area, ending deep enough saturation for precipitation processes
to take place. Precipitation type looks to be largely rain for
central Illinois given a deep warm layer just off the surface. Still
some chance for light freezing rain with temperatures hovering very
near the freezing mark at the surface. Farther to the north, the
warm layer off the surface is less pronounced, which could allow for
snow or a mix of rain and snow to reach the surface..
A high pressure ridge will develop over the plains for much of the
week with NW flow and dry conditions for central IL. Temperatures
will remain below normal for much of the week as a result. Friday
and Saturday may see a substantial warmup as the plains ridge shifts
over IL. Only chance for precipitation in the extended forecast at
this time appears to be around Friday morning as a few models hint
at a weak disturbance meandering through the region at this time.
&&
.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
ISSUED AT 500 PM CST SAT DEC 6 2014
MVFR and IFR cigs slowly shifting south early this evening and at
the same time, a large area of cirrus clouds was streaking east into
our area. A band of moisture/clouds (MVFR) was also seen over northeast
Illinois coming off of Lake Michigan and was tracking southwest and
may affect BMI and CMI in the 01z to 03z time frame. Short term high
resolution models continue to push the low clouds south over the next
several hours reaching SPI and DEC by around 02z. These two sites look
to be the pivot point with respect to their eventual movement later
tonight with models suggesting more of a southwest to west track as
high pressure shifts over the central Great Lakes and our flow becomes
more northeast to east. Once we do lose the MVFR cigs, it appears we
will have to deal with the mid and high level (VFR) cigs late tonight
and into Sunday. Surface winds will be northeast to east at 5 to
10 kts tonight with winds becoming east to southeast at 10 to 15 kts
on Sunday.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Geelhart
LONG TERM...Onton
AVIATION...Smith
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
351 PM EST FRI DEC 5 2014
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 347 PM EST FRI DEC 5 2014
WIDESPREAD RAIN WILL CONTINUE THROUGH SATURDAY MORNING AS LOW
PRESSURE TRACKS THROUGH THE OHIO VALLEY. WITH THE EXCEPTION OF A FEW
SHOWERS MONDAY AS LOW PRESSURE PASSES THROUGH THE GREAT LAKES...DRY
AND SEASONABLY COOL WEATHER CAN BE EXPECTED THROUGH MUCH OF NEXT
WEEK.
&&
.NEAR TERM /TONIGHT/...
ISSUED AT 347 PM EST FRI DEC 5 2014
RAIN CONTINUES ACROSS THE FORECAST AREA THIS AFTERNOON...AND EXPECT
ONLY TO INCREASE FURTHER IN INTENSITY OVER THE NEXT SEVERAL HOURS
WITH THE APPROACH OF LOW PRESSURE. TEMPS RANGED FROM THE UPPER 30S
NORTH TO UPPER 40S ACROSS FAR SOUTHERN COUNTIES AT 20Z.
A RAW WET NIGHT UPCOMING AS LOW PRESSURE CURRENTLY OVER THE OZARKS
TRACKS E/NE ALONG THE OHIO RIVER TONIGHT. MODEL GUIDANCE IN
EXCELLENT AGREEMENT ON SPREADING ANOTHER WAVE OF HEAVIER CONVECTIVE
RAINFALL INTO THE FORECAST AREA LATE THIS AFTERNOON THROUGH THE
EVENING. FOCUS FOR THE HEAVIEST RAINS REMAINS ACROSS THE SOUTHERN
HALF OF THE FORECAST AREA BETWEEN 00-06Z AS STRONGER LOW LEVEL
CONVERGENCE ALIGNS ALONG THE 850MB BAROCLINIC ZONE AND AREA OF
ENHANCED ISENTROPIC LIFT. A LOW LEVEL JET OVER THE TENNESSEE VALLEY
WILL TRANSPORT DEEPER MOISTURE UP INTO THE REGION AS WELL. APPROACH
OF THE UPPER WAVE WILL PROMOTE DIFFLUENCE ALOFT...FURTHER ASSISTING
LIFT FOR EFFICIENT RAINFALL.
THERE IS SOME WEAK ELEVATED INSTABILITY PRESENT...BUT JUST DO NOT
SEE ENOUGH TO JUSTIFY AN ISOLATED THUNDER MENTION TONIGHT. BETTER
THREAT FOR A FEW STORMS WILL EXIST CLOSER TO THE SURFACE LOW TRACK
ALONG THE OHIO RIVER. POTENTIAL EXISTS FOR UP TO 1.5 INCHES ALONG
AND SOUTH OF I-70 BY SATURDAY MORNING. WILL CONTINUE WITH
CATEGORICAL POPS TONIGHT. HEAVIER RAINS WILL BEGIN TO SHIFT EAST
AFTER 06Z...BUT LINGERING MID LEVEL DEFORMATION BAND WILL MAINTAIN
LIGHTER RAIN FOR MUCH OF THE REST OF THE NIGHT. HRRR AND WRF-NMM/ARW
BRING BACK END OF THE RAIN INTO THE NORTHERN WABASH VALLEY AROUND OR
SHORTLY BEFORE DAYBREAK. WINDS WILL PICK UP LATE TONIGHT AS WELL AS
A BRISK NORTHERLY FLOW DEVELOPS BEHIND THE SURFACE LOW.
TEMPS...MOS APPEARS A BIT AGGRESSIVE IN BRINGING THE COLDER AIR IN
PRIOR TO 12Z. GENERALLY TRENDED A DEGREE OR TWO ABOVE MAVMOS
GUIDANCE WITH LOWS RANGING FROM THE MID 30S NORTH TO LOWER 40S
SOUTH.
&&
.SHORT TERM /SATURDAY THROUGH MONDAY/...
ISSUED AT 347 PM EST FRI DEC 5 2014
FORECAST CHALLENGES FOCUS ON THE DEPARTURE OF THE RAIN SATURDAY
MORNING...AND POSSIBILITY FOR LIGHT PRECIP WITH A WEAK SYSTEM ON
MONDAY.
THE UPPER WAVE AND SURFACE LOW WILL CONTINUE TO MOVE AWAY TO THE
EAST WITH LIGHT RAIN ENDING FROM NORTHWEST TO SOUTHEAST DURING THE
MORNING. WRF DATA LOOKS VERY GOOD WITH RESPECT TO TIMING AND WAS
UTILIZED FOR MORNING POPS. EXPECT THE ENTIRE FORECAST AREA WILL BE
FREE OF PRECIP AROUND MIDDAY. DRIER AIR ALOFT WILL QUICKLY ADVECT
INTO THE REGION WITH STRONG HIGH PRESSURE SATURDAY AFTERNOON...BUT
RH PROGS AND MODEL SOUNDINGS INDICATE LINGERING LOW LEVEL MOISTURE
REMAINING TRAPPED BENEATH A SLOWLY WEAKENING INVERSION. EXPECT LOWER
CLOUDS TO LINGER AS A RESULT...WITH FULL CLEARING OF THE CLOUD DECK
NOT COMING UNTIL SATURDAY EVENING AS STRONGER SUBSIDENCE ENABLES
DRIER AIR TO INFILTRATE THE NEAR SURFACE LAYER.
HIGH PRESSURE RIDGE WILL DRIFT SLOWLY THROUGH THE GREAT LAKES
SATURDAY NIGHT AND SUNDAY...PROVIDING A DRY COOL E/NE FLOW ACROSS
CENTRAL INDIANA. EXPECT ABUNDANT SUNSHINE ON SUNDAY...WHICH
AMAZINGLY WOULD BE THE FIRST DAY WITH EXTENDED SUNSHINE AND BLUE
SKIES FOR MANY SINCE NOVEMBER 21.
MID AND HIGH LEVEL CLOUDS WILL INCREASE AGAIN BEGINNING SUNDAY NIGHT
WITH SKIES BECOMING FAIRLY CLOUDY MONDAY AS AN UPPER WAVE AND
ASSOCIATED LOW PRESSURE ASSOCIATED WITH THE NORTHERN JET STREAM
TRACK INTO THE GREAT LAKES. DESPITE INCREASING ISENTROPIC LIFT AND
HINT OF SOME DEVELOPING LOW LEVEL CONVERGENCE...MOISTURE PROFILES
LARGELY LOOK UNIMPRESSIVE AND FOCUSED PRIMARILY ABOVE 10KFT. HAVE A
HARD TIME JUSTIFYING MUCH HIGHER THAN LOW CHANCE POPS AS THE SYSTEM
PASSES THROUGH. ENOUGH COLD AIR PRESENT THAT MAY SEE A MIXTURE OF
LIGHT SNOW AND RAIN IN THE NORTHERN WABASH VALLEY MONDAY MORNING
BEFORE PRECIP TRANSITIONS TO ALL RAIN. REGARDLESS...QPF VALUES AT
THIS POINT LOOK NO HIGHER THAN A FEW HUNDREDTHS.
TEMPS...LEANED CLOSER TO COOLER METMOS FOR SATURDAY HIGHS WITH THE
LINGER LOW CLOUDS. WENT NEAR MOS FOR SUNDAY THEN UNDERCUT FOR MONDAY
AND LEANED CLOSER TO ECMWF ENSEMBLE MEAN TEMPS. DESPITE WARM
ADVECTION AHEAD OF THE SURFACE LOW...MEXMOS LOOKS TOO AGGRESSIVE
WITH WARMING TEMPS. LEANED TOWARDS WARMER METMOS FOR SATURDAY NIGHT
LOWS AND TOOK A MODEL BLEND FOR SUNDAY NIGHT.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
ISSUED AT 347 PM EST FRI DEC 5 2014
ENSEMBLES INDICATE A FAIRLY STRONG UPPER TROUGH THAT IS EXPECTED TO
DROP SOUTHEAST ACROSS THE GREAT LAKES MONDAY NIGHT INTO TUESDAY. A
FEW OF THE ENSEMBLES SUGGEST THERE MAY A SOME LIGHT RAIN OR SNOW
SHOWERS DURING THIS PERIOD AS THE TROUGH BRUSHES BY...BUT NOT ENOUGH
OF A SIGNAL TO PUT IN THE FORECAST AT THIS TIME. WILL MONITOR THE
TRENDS.
OTHERWISE...SOME OF THE ENSEMBLES CUTOFF THE SOUTHERN PART OF THE
EARLY WEEK TROUGH OVER THE EASTERN PARTS OF THE COUNTRY LATER NEXT
WEEK...WHILE OTHERS ARE MORE PROGRESSIVE. DOESN/T APPEAR EITHER
SOLUTION WILL RESULT IN MUCH OF A PRECIPITATION THREAT OVER THE
AREA...BUT IF THE LESS PROGRESSIVE SOLUTIONS END UP BEING
CORRECT...THE WARMUP LATE NEXT WEEK MAY BE TEMPERED SOME.
&&
.AVIATION /DISCUSSION FOR THE 052100Z TAF UPDATE/...
ISSUED AT 351 PM EST FRI DEC 5 2014
VISIBILITY AT KIND SHOULD REMAIN AROUND 2 MILES FOR A BIT LONGER.
ONLY MADE MINOR TWEAKS TO TAF.
PREVIOUS DISCUSSION FOLLOWS...
LARGE AREA OF RAIN CURRENTLY AFFECTING THE TAF SITES...AND IS
EXPECTED TO CONTINUE THROUGH 060600Z. APPEARS STRONGEST LIFT WILL
MOVE THROUGH AROUND 052200Z-060400Z AS A 40-50KT LOW LEVEL JET NOSES
INTO THE OHIO VALLEY. AS A RESULT...POCKETS OF MODERATE/HEAVY RAIN
EXPECTED DURING THAT TIME.
CEILINGS GENERALLY 004-007 AGL EXPECTED THROUGH THIS EVENING. THE
LIFR CONDITIONS WILL TEND TO LIFT AS TIME GOES BY AS STRONGER LIFT
HELPS TO MIX UP THE LOWER AIR MASS. AREAS OF IFR VISIBILITY
RESTRICTIONS EXPECTED THROUGH LATE EVENING...ESPECIALLY IN THE
HEAVIER RAIN AREAS.
INITIALLY LIGHT SURFACE WINDS EXPECTED TO GRADUALLY BACK AROUND TO
010-030 DEGREES AND INCREASE TO 10-13KTS BY LATE EVENING AS SURFACE
LOW APPROACHES.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...RYAN
SHORT TERM...RYAN
LONG TERM....JAS
AVIATION...JAS/50
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT:
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AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
347 PM EST FRI DEC 5 2014
.UPDATE...
THE SYNOPSIS...NEAR TERM...SHORT TERM AND LONG TERM SECTIONS HAVE
BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 347 PM EST FRI DEC 5 2014
WIDESPREAD RAIN WILL CONTINUE THROUGH SATURDAY MORNING AS LOW
PRESSURE TRACKS THROUGH THE OHIO VALLEY. WITH THE EXCEPTION OF A FEW
SHOWERS MONDAY AS LOW PRESSURE PASSES THROUGH THE GREAT LAKES...DRY
AND SEASONABLY COOL WEATHER CAN BE EXPECTED THROUGH MUCH OF NEXT
WEEK.
&&
.NEAR TERM /TONIGHT/...
ISSUED AT 347 PM EST FRI DEC 5 2014
RAIN CONTINUES ACROSS THE FORECAST AREA THIS AFTERNOON...AND EXPECT
ONLY TO INCREASE FURTHER IN INTENSITY OVER THE NEXT SEVERAL HOURS
WITH THE APPROACH OF LOW PRESSURE. TEMPS RANGED FROM THE UPPER 30S
NORTH TO UPPER 40S ACROSS FAR SOUTHERN COUNTIES AT 20Z.
A RAW WET NIGHT UPCOMING AS LOW PRESSURE CURRENTLY OVER THE OZARKS
TRACKS E/NE ALONG THE OHIO RIVER TONIGHT. MODEL GUIDANCE IN
EXCELLENT AGREEMENT ON SPREADING ANOTHER WAVE OF HEAVIER CONVECTIVE
RAINFALL INTO THE FORECAST AREA LATE THIS AFTERNOON THROUGH THE
EVENING. FOCUS FOR THE HEAVIEST RAINS REMAINS ACROSS THE SOUTHERN
HALF OF THE FORECAST AREA BETWEEN 00-06Z AS STRONGER LOW LEVEL
CONVERGENCE ALIGNS ALONG THE 850MB BAROCLINIC ZONE AND AREA OF
ENHANCED ISENTROPIC LIFT. A LOW LEVEL JET OVER THE TENNESSEE VALLEY
WILL TRANSPORT DEEPER MOISTURE UP INTO THE REGION AS WELL. APPROACH
OF THE UPPER WAVE WILL PROMOTE DIFFLUENCE ALOFT...FURTHER ASSISTING
LIFT FOR EFFICIENT RAINFALL.
THERE IS SOME WEAK ELEVATED INSTABILITY PRESENT...BUT JUST DO NOT
SEE ENOUGH TO JUSTIFY AN ISOLATED THUNDER MENTION TONIGHT. BETTER
THREAT FOR A FEW STORMS WILL EXIST CLOSER TO THE SURFACE LOW TRACK
ALONG THE OHIO RIVER. POTENTIAL EXISTS FOR UP TO 1.5 INCHES ALONG
AND SOUTH OF I-70 BY SATURDAY MORNING. WILL CONTINUE WITH
CATEGORICAL POPS TONIGHT. HEAVIER RAINS WILL BEGIN TO SHIFT EAST
AFTER 06Z...BUT LINGERING MID LEVEL DEFORMATION BAND WILL MAINTAIN
LIGHTER RAIN FOR MUCH OF THE REST OF THE NIGHT. HRRR AND WRF-NMM/ARW
BRING BACK END OF THE RAIN INTO THE NORTHERN WABASH VALLEY AROUND OR
SHORTLY BEFORE DAYBREAK. WINDS WILL PICK UP LATE TONIGHT AS WELL AS
A BRISK NORTHERLY FLOW DEVELOPS BEHIND THE SURFACE LOW.
TEMPS...MOS APPEARS A BIT AGGRESSIVE IN BRINGING THE COLDER AIR IN
PRIOR TO 12Z. GENERALLY TRENDED A DEGREE OR TWO ABOVE MAVMOS
GUIDANCE WITH LOWS RANGING FROM THE MID 30S NORTH TO LOWER 40S
SOUTH.
&&
.SHORT TERM /SATURDAY THROUGH MONDAY/...
ISSUED AT 347 PM EST FRI DEC 5 2014
FORECAST CHALLENGES FOCUS ON THE DEPARTURE OF THE RAIN SATURDAY
MORNING...AND POSSIBILITY FOR LIGHT PRECIP WITH A WEAK SYSTEM ON
MONDAY.
THE UPPER WAVE AND SURFACE LOW WILL CONTINUE TO MOVE AWAY TO THE
EAST WITH LIGHT RAIN ENDING FROM NORTHWEST TO SOUTHEAST DURING THE
MORNING. WRF DATA LOOKS VERY GOOD WITH RESPECT TO TIMING AND WAS
UTILIZED FOR MORNING POPS. EXPECT THE ENTIRE FORECAST AREA WILL BE
FREE OF PRECIP AROUND MIDDAY. DRIER AIR ALOFT WILL QUICKLY ADVECT
INTO THE REGION WITH STRONG HIGH PRESSURE SATURDAY AFTERNOON...BUT
RH PROGS AND MODEL SOUNDINGS INDICATE LINGERING LOW LEVEL MOISTURE
REMAINING TRAPPED BENEATH A SLOWLY WEAKENING INVERSION. EXPECT LOWER
CLOUDS TO LINGER AS A RESULT...WITH FULL CLEARING OF THE CLOUD DECK
NOT COMING UNTIL SATURDAY EVENING AS STRONGER SUBSIDENCE ENABLES
DRIER AIR TO INFILTRATE THE NEAR SURFACE LAYER.
HIGH PRESSURE RIDGE WILL DRIFT SLOWLY THROUGH THE GREAT LAKES
SATURDAY NIGHT AND SUNDAY...PROVIDING A DRY COOL E/NE FLOW ACROSS
CENTRAL INDIANA. EXPECT ABUNDANT SUNSHINE ON SUNDAY...WHICH
AMAZINGLY WOULD BE THE FIRST DAY WITH EXTENDED SUNSHINE AND BLUE
SKIES FOR MANY SINCE NOVEMBER 21.
MID AND HIGH LEVEL CLOUDS WILL INCREASE AGAIN BEGINNING SUNDAY NIGHT
WITH SKIES BECOMING FAIRLY CLOUDY MONDAY AS AN UPPER WAVE AND
ASSOCIATED LOW PRESSURE ASSOCIATED WITH THE NORTHERN JET STREAM TRACK
INTO THE GREAT LAKES. DESPITE INCREASING ISENTROPIC LIFT AND HINT OF
SOME DEVELOPING LOW LEVEL CONVERGENCE...MOISTURE PROFILES LARGELY
LOOK UNIMPRESSIVE AND FOCUSED PRIMARILY ABOVE 10KFT. HAVE A HARD
TIME JUSTIFYING MUCH HIGHER THAN LOW CHANCE POPS AS THE SYSTEM
PASSES THROUGH. ENOUGH COLD AIR PRESENT THAT MAY SEE A MIXTURE OF
LIGHT SNOW AND RAIN IN THE NORTHERN WABASH VALLEY MONDAY MORNING
BEFORE PRECIP TRANSITIONS TO ALL RAIN. REGARDLESS...QPF VALUES AT
THIS POINT LOOK NO HIGHER THAN A FEW HUNDREDTHS.
TEMPS...LEANED CLOSER TO COOLER METMOS FOR SATURDAY HIGHS WITH THE
LINGER LOW CLOUDS. WENT NEAR MOS FOR SUNDAY THEN UNDERCUT FOR MONDAY
AND LEANED CLOSER TO ECMWF ENSEMBLE MEAN TEMPS. DESPITE WARM ADVECTION
AHEAD OF THE SURFACE LOW...MEXMOS LOOKS TOO AGGRESSIVE WITH WARMING
TEMPS. LEANED TOWARDS WARMER METMOS FOR SATURDAY NIGHT LOWS AND TOOK
A MODEL BLEND FOR SUNDAY NIGHT.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
ISSUED AT 347 PM EST FRI DEC 5 2014
ENSEMBLES INDICATE A FAIRLY STRONG UPPER TROUGH THAT IS EXPECTED TO
DROP SOUTHEAST ACROSS THE GREAT LAKES MONDAY NIGHT INTO TUESDAY. A
FEW OF THE ENSEMBLES SUGGEST THERE MAY A SOME LIGHT RAIN OR SNOW
SHOWERS DURING THIS PERIOD AS THE TROUGH BRUSHES BY...BUT NOT ENOUGH
OF A SIGNAL TO PUT IN THE FORECAST AT THIS TIME. WILL MONITOR THE
TRENDS.
OTHERWISE...SOME OF THE ENSEMBLES CUTOFF THE SOUTHERN PART OF THE
EARLY WEEK TROUGH OVER THE EASTERN PARTS OF THE COUNTRY LATER NEXT
WEEK...WHILE OTHERS ARE MORE PROGRESSIVE. DOESN/T APPEAR EITHER
SOLUTION WILL RESULT IN MUCH OF A PRECIPITATION THREAT OVER THE
AREA...BUT IF THE LESS PROGRESSIVE SOLUTIONS END UP BEING
CORRECT...THE WARMUP LATE NEXT WEEK MAY BE TEMPERED SOME.
&&
.AVIATION /DISCUSSION FOR THE 051800Z TAFS/...
ISSUED AT 1141 AM EST FRI DEC 5 2014
LARGE AREA OF RAIN CURRENTLY AFFECTING THE TAF SITES...AND IS
EXPECTED TO CONTINUE THROUGH 060600Z. APPEARS STRONGEST LIFT WILL
MOVE THROUGH AROUND 052200Z-060400Z AS A 40-50KT LOW LEVEL JET NOSES
INTO THE OHIO VALLEY. AS A RESULT...POCKETS OF MODERATE/HEAVY RAIN
EXPECTED DURING THAT TIME.
CEILINGS GENERALLY 004-007 AGL EXPECTED THROUGH THIS EVENING. THE
LIFR CONDITIONS WILL TEND TO LIFT AS TIME GOES BY AS STRONGER LIFT
HELPS TO MIX UP THE LOWER AIR MASS. AREAS OF IFR VISIBILITY
RESTRICTIONS EXPECTED THROUGH LATE EVENING...ESPECIALLY IN THE
HEAVIER RAIN AREAS.
INITIALLY LIGHT SURFACE WINDS EXPECTED TO GRADUALLY BACK AROUND TO
010-030 DEGREES AND INCREASE TO 10-13KTS BY LATE EVENING AS SURFACE
LOW APPROACHES.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...RYAN
SHORT TERM...RYAN
LONG TERM....JAS
AVIATION...JAS
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT:
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AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
924 AM EST FRI DEC 5 2014
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 406 AM EST FRI DEC 5 2014
LOW PRESSURE WILL MOVE ALONG A FRONTAL ZONE NEAR THE OHIO RIVER
TODAY INTO SATURDAY...BRINGING WIDESPREAD RAINFALL TO CENTRAL
INDIANA. DENSE FOG WILL ALSO BE AN ISSUE THROUGH MIDDAY TODAY.
PRECIPITATION WILL END BY MIDDAY SATURDAY AS HIGH PRESSURE BUILDS
INTO THE AREA. ASIDE FROM A CHANCE OF RAIN ON MONDAY AS A WEAK
FRONTAL BOUNDARY PUSHES THROUGH THE REGION...DRY WEATHER CAN BE
EXPECTED FOR THE REMAINDER OF THE FORECAST PERIOD.
&&
.NEAR TERM /TODAY AND TONIGHT/...
ISSUED AT 406 AM EST FRI DEC 5 2014
DENSE FOG HAS DEVELOPED AND ADVECTED INTO THE AREA THIS
MORNING...AND PER HRRR VISIBILITY PROGS EXPECT IT TO PUSH A BIT
FURTHER NORTH AND EAST OVER THE NEXT COUPLE OF HOURS. VISIBILITIES
IN THIS AREA LOOK TO OFTEN BE ONE QUARTER MILE WITH A FEW AREAS OF
NEAR ZERO VISIBILITY. AS SUCH...HAVE ISSUED A DENSE FOG ADVISORY
IN COLLABORATION WITH SURROUNDING OFFICES...AND WILL KEEP THE
ADVISORY GOING UNTIL 15Z...WHEN PROGS SUGGEST VISIBILITY SHOULD
IMPROVE. THERE IS SOME CHANCE VISIBILITIES MAY IMPROVE EARLIER AS
RAINFALL DEVELOPS ACROSS THE SOUTHWEST...AND IF THIS BECOMES THE
CASE THE ADVISORY MAY BE ABLE TO DROP EARLY.
LOW PRESSURE WILL DEVELOP AND PUSH EASTWARD ALONG AN UNDULATING
FRONTAL ZONE TO OUR SOUTH TODAY...AND EXPECT WIDESPREAD RAINFALL
TO DEVELOP ACROSS CENTRAL INDIANA...ESPECIALLY THIS AFTERNOON.
WILL RAMP POPS UP GRADUALLY DURING THE MORNING TO 90 TO 100
PERCENT ACROSS THE ENTIRE AREA BY LATE AFTERNOON.
LATE AFTERNOON INTO THE OVERNIGHT...WHILE UPRIGHT INSTABILITY IS
NIL...SOME RELATIVELY STOUT FRONTOGENETIC FORCING WILL PUSH INTO
THE AREA...ALONG WITH SOME INSTABILITY IN THE FORM OF SATURATED
NEGATIVE EPV. ADDITIONALLY...FORECAST SOUNDINGS ACROSS THE
SOUTHERN FORECAST AREA SHOW LIFTED INDEX VALUES NEAR 0 TO 1 WITH A
PARCEL LIFTED FROM ROUGHLY 900 MB...AROUND THE TOP OF THE
INVERSION. ALL THIS IS TO SAY THAT A STRAY RUMBLE OF THUNDER
ACROSS THE FAR SOUTH CANNOT COMPLETELY BE RULED OUT...BUT IS LOW
PROBABILITY ENOUGH TO EXCLUDE FROM THE GRIDS UNTIL DEVELOPMENT
SAYS OTHERWISE.
POPS WILL REMAIN 90 TO 100 PERCENT THROUGHOUT THE NIGHT...BUT THE
MOST INTENSE OF THE RAINFALL APPEARS LIKELY TO OCCUR LATE
AFTERNOON THROUGH LATE EVENING WHEN THE MESOSCALE FORCING IS
STRONGEST. TOTAL RAINFALL AMOUNTS OF AROUND ONE INCH ACROSS THE
NORTH...TO AN INCH TO INCH AND A HALF ACROSS THE SOUTH APPEAR
LIKELY.
ON TEMPS...USED ADJUSTED RAW MODEL BLENDS AS THE RAW MODEL TEMPS
WILL LIKELY BEST CAPTURE WHAT SHOULD BE A VERY STRONG TEMPERATURE
GRADIENT ACROSS PORTIONS OF THE AREA TODAY AND TONIGHT. NONDIURNAL
TEMPERATURE PROGRESSION APPEARS LIKELY ACROSS THE FAR SOUTH
NEAREST THE LOW AND THE FRONTAL ZONE TODAY AND TONIGHT...WITH
HIGH TEMPERATURES FOR THE DATE POTENTIALLY REACHED NEAR MIDNIGHT.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
ISSUED AT 406 AM EST FRI DEC 5 2014
WHILE SOME PRECIP APPEARS LIKELY TO PERSIST INTO SATURDAY
MORNING...ESPECIALLY ACROSS THE EASTERN PORTIONS OF THE FORECAST
AREA...MODEL GUIDANCE IS IN GOOD AGREEMENT THAT DRY WEATHER WILL
RETURN TO THE AREA BY SATURDAY AFTERNOON...AND REMAIN SO THROUGH
THE REMAINDER OF THE SHORT TERM.
APPEARS THAT LOW LEVEL THERMAL PROFILES WILL REMAIN WARM ENOUGH
THROUGH THE END OF THE PRECIPITATION THAT NO FREEZING OR FROZEN
PRECIP IS ANTICIPATED.
ON TEMPS...MODEL CONSENSUS NUMBERS APPEARED REASONABLE THROUGHOUT
WITH A FEW MINOR TWEAKS...PER LOW LEVEL THICKNESS PROGS AND TEMPS.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
ISSUED AT 228 AM EST FRI DEC 5 2014
GENERALLY QUIET WEATHER WITH NEAR NORMAL TEMPERATURES LOOK IN
STORE DURING THIS PERIOD. THE ECMWF AND GFS HINT AT A COLD FRONTAL
PASSES ACROSS THE AREA ON MONDAY AS LOW PRESSURE MOVES THROUGH THE
GREAT LAKES. AT THIS TIME MOISTURE APPEARS LIMITED AS THE LOWER
LEVEL FLOW AHEAD OF THE COLD FRONT FAILS TO OPEN UP FROM THE
GULF. THUS HAVE INCLUDED SOME LOW CHC POPS FOR NOW AS WE CANNOT
RULE OUT A LIGHT PRECIPITATION EVENT.
COOL HIGH PRESSURE THEN BUILD ACROSS THE MISSISSIPPI AND OHIO
RIVER VALLEYS THROUGH THE REST OF THE PERIOD. ALOFT NORTHWEST FLOW
PERSISTS THROUGH MUCH OF THE NEXT WORK WEEK WITH LITTLE IN THE WAY
OF UPPER DYNAMICS PUSHING THROUGH THE OHIO VALLEY. BY THURSDAY AND
FRIDAY...REINFORCING RIDGING APPEARS TO BE BUILDING ACROSS THE
PLAINS STATES AND MISSISSIPPI VALLEY. THUS SHOULD CONTINUE THE
TREND OF DRY WEATHER FOR MUCH OF NEXT WEEK.
&&
.AVIATION /DISCUSSION FOR THE 051500Z KIND TAF UPDATE/...
ISSUED AT 924 AM EST FRI DEC 5 2014
LARGE AREA OF RAIN CURRENTLY APPROACHING THE KIND TERMINAL. SHOULD
REACH KIND AROUND 051600Z BASED ON EXTRAPOLATION. LOW VISIBILITIES
SHOULD IMPROVE SOMEWHAT ONCE THE RAIN STARTS...BUT THE LIFR CEILINGS
WILL PROBABLY LINGER.
PREVIOUS DISCUSSION FOLLOWS.
IFR AND LIFR CONDITIONS ARE EXPECTED FOR MUCH OF THE TAF PERIOD.
A SURFACE WARM FRONT IN PLACE ACROSS CENTRAL ILLINOIS AND CENTRAL
INDIANA WILL BE THE PATH THAT AN AREA OF LOW PRESSURE WILL FOLLOW
ACROSS CENTRAL INDIANA DURING THE TAF PERIOD. RAIN...LOW CIGS AND
AND LOW VISIBILITIES ARE EXPECTED AS THE SYSTEM PASSES. FAVORABLE
DYNAMICS REMAIN IN PLACE ALOFT AS TIME HEIGHTS AND FORECAST
SOUNDINGS CONTINUE TO REVEAL AS SATURATED COLUMN.
IMPROVEMENT IS EXPECTED LATE TONIGHT AS THE LOW DEPARTS TO THE
SOUTHEAST AND NORTHERLY WINDS ALLOW SOME DRIER AIR TO ARRIVE
ACROSS THE AREA.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 10 AM EST THIS MORNING FOR INZ028-035-
036-043>047-051>056-060>065-067>072.
&&
$$
SYNOPSIS...NIELD
NEAR TERM...NIELD
SHORT TERM...NIELD
LONG TERM...PUMA
AVIATION...JP/JAS
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSINDIANAPOLIS
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
557 AM EST FRI DEC 5 2014
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 406 AM EST FRI DEC 5 2014
LOW PRESSURE WILL MOVE ALONG A FRONTAL ZONE NEAR THE OHIO RIVER
TODAY INTO SATURDAY...BRINGING WIDESPREAD RAINFALL TO CENTRAL
INDIANA. DENSE FOG WILL ALSO BE AN ISSUE THROUGH MIDDAY TODAY.
PRECIPITATION WILL END BY MIDDAY SATURDAY AS HIGH PRESSURE BUILDS
INTO THE AREA. ASIDE FROM A CHANCE OF RAIN ON MONDAY AS A WEAK
FRONTAL BOUNDARY PUSHES THROUGH THE REGION...DRY WEATHER CAN BE
EXPECTED FOR THE REMAINDER OF THE FORECAST PERIOD.
&&
.NEAR TERM /TODAY AND TONIGHT/...
ISSUED AT 406 AM EST FRI DEC 5 2014
DENSE FOG HAS DEVELOPED AND ADVECTED INTO THE AREA THIS
MORNING...AND PER HRRR VISIBILITY PROGS EXPECT IT TO PUSH A BIT
FURTHER NORTH AND EAST OVER THE NEXT COUPLE OF HOURS. VISIBILITIES
IN THIS AREA LOOK TO OFTEN BE ONE QUARTER MILE WITH A FEW AREAS OF
NEAR ZERO VISIBILITY. AS SUCH...HAVE ISSUED A DENSE FOG ADVISORY
IN COLLABORATION WITH SURROUNDING OFFICES...AND WILL KEEP THE
ADVISORY GOING UNTIL 15Z...WHEN PROGS SUGGEST VISIBILITY SHOULD
IMPROVE. THERE IS SOME CHANCE VISIBILITIES MAY IMPROVE EARLIER AS
RAINFALL DEVELOPS ACROSS THE SOUTHWEST...AND IF THIS BECOMES THE
CASE THE ADVISORY MAY BE ABLE TO DROP EARLY.
LOW PRESSURE WILL DEVELOP AND PUSH EASTWARD ALONG AN UNDULATING
FRONTAL ZONE TO OUR SOUTH TODAY...AND EXPECT WIDESPREAD RAINFALL
TO DEVELOP ACROSS CENTRAL INDIANA...ESPECIALLY THIS AFTERNOON.
WILL RAMP POPS UP GRADUALLY DURING THE MORNING TO 90 TO 100
PERCENT ACROSS THE ENTIRE AREA BY LATE AFTERNOON.
LATE AFTERNOON INTO THE OVERNIGHT...WHILE UPRIGHT INSTABILITY IS
NIL...SOME RELATIVELY STOUT FRONTOGENETIC FORCING WILL PUSH INTO
THE AREA...ALONG WITH SOME INSTABILITY IN THE FORM OF SATURATED
NEGATIVE EPV. ADDITIONALLY...FORECAST SOUNDINGS ACROSS THE
SOUTHERN FORECAST AREA SHOW LIFTED INDEX VALUES NEAR 0 TO 1 WITH A
PARCEL LIFTED FROM ROUGHLY 900 MB...AROUND THE TOP OF THE
INVERSION. ALL THIS IS TO SAY THAT A STRAY RUMBLE OF THUNDER
ACROSS THE FAR SOUTH CANNOT COMPLETELY BE RULED OUT...BUT IS LOW
PROBABILITY ENOUGH TO EXCLUDE FROM THE GRIDS UNTIL DEVELOPMENT
SAYS OTHERWISE.
POPS WILL REMAIN 90 TO 100 PERCENT THROUGHOUT THE NIGHT...BUT THE
MOST INTENSE OF THE RAINFALL APPEARS LIKELY TO OCCUR LATE
AFTERNOON THROUGH LATE EVENING WHEN THE MESOSCALE FORCING IS
STRONGEST. TOTAL RAINFALL AMOUNTS OF AROUND ONE INCH ACROSS THE
NORTH...TO AN INCH TO INCH AND A HALF ACROSS THE SOUTH APPEAR
LIKELY.
ON TEMPS...USED ADJUSTED RAW MODEL BLENDS AS THE RAW MODEL TEMPS
WILL LIKELY BEST CAPTURE WHAT SHOULD BE A VERY STRONG TEMPERATURE
GRADIENT ACROSS PORTIONS OF THE AREA TODAY AND TONIGHT. NONDIURNAL
TEMPERATURE PROGRESSION APPEARS LIKELY ACROSS THE FAR SOUTH
NEAREST THE LOW AND THE FRONTAL ZONE TODAY AND TONIGHT...WITH
HIGH TEMPERATURES FOR THE DATE POTENTIALLY REACHED NEAR MIDNIGHT.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
ISSUED AT 406 AM EST FRI DEC 5 2014
WHILE SOME PRECIP APPEARS LIKELY TO PERSIST INTO SATURDAY
MORNING...ESPECIALLY ACROSS THE EASTERN PORTIONS OF THE FORECAST
AREA...MODEL GUIDANCE IS IN GOOD AGREEMENT THAT DRY WEATHER WILL
RETURN TO THE AREA BY SATURDAY AFTERNOON...AND REMAIN SO THROUGH
THE REMAINDER OF THE SHORT TERM.
APPEARS THAT LOW LEVEL THERMAL PROFILES WILL REMAIN WARM ENOUGH
THROUGH THE END OF THE PRECIPITATION THAT NO FREEZING OR FROZEN
PRECIP IS ANTICIPATED.
ON TEMPS...MODEL CONSENSUS NUMBERS APPEARED REASONABLE THROUGHOUT
WITH A FEW MINOR TWEAKS...PER LOW LEVEL THICKNESS PROGS AND TEMPS.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
ISSUED AT 228 AM EST FRI DEC 5 2014
GENERALLY QUIET WEATHER WITH NEAR NORMAL TEMPERATURES LOOK IN
STORE DURING THIS PERIOD. THE ECMWF AND GFS HINT AT A COLD FRONTAL
PASSES ACROSS THE AREA ON MONDAY AS LOW PRESSURE MOVES THROUGH THE
GREAT LAKES. AT THIS TIME MOISTURE APPEARS LIMITED AS THE LOWER
LEVEL FLOW AHEAD OF THE COLD FRONT FAILS TO OPEN UP FROM THE
GULF. THUS HAVE INCLUDED SOME LOW CHC POPS FOR NOW AS WE CANNOT
RULE OUT A LIGHT PRECIPITATION EVENT.
COOL HIGH PRESSURE THEN BUILD ACROSS THE MISSISSIPPI AND OHIO
RIVER VALLEYS THROUGH THE REST OF THE PERIOD. ALOFT NORTHWEST FLOW
PERSISTS THROUGH MUCH OF THE NEXT WORK WEEK WITH LITTLE IN THE WAY
OF UPPER DYNAMICS PUSHING THROUGH THE OHIO VALLEY. BY THURSDAY AND
FRIDAY...REINFORCING RIDGING APPEARS TO BE BUILDING ACROSS THE
PLAINS STATES AND MISSISSIPPI VALLEY. THUS SHOULD CONTINUE THE
TREND OF DRY WEATHER FOR MUCH OF NEXT WEEK.
&&
.AVIATION /DISCUSSION FOR THE 051200Z TAFS/...
ISSUED AT 547 AM EST FRI DEC 5 2014
IFR AND LIFR CONDITIONS ARE EXPECTED FOR MUCH OF THE TAF PERIOD.
A SURFACE WARM FRONT IN PLACE ACROSS CENTRAL ILLINOIS AND CENTRAL
INDIANA WILL BE THE PATH THAT AN AREA OF LOW PRESSURE WILL FOLLOW
ACROSS CENTRAL INDIANA DURING THE TAF PERIOD. RAIN...LOW CIGS AND
AND LOW VISIBILITIES ARE EXPECTED AS THE SYSTEM PASSES. FAVORABLE
DYNAMICS REMAIN IN PLACE ALOFT AS TIME HEIGHTS AND FORECAST
SOUNDINGS CONTINUE TO REVEAL AS SATURATED COLUMN.
IMPROVEMENT IS EXPECTED LATE TONIGHT AS THE LOW DEPARTS TO THE
SOUTHEAST AND NORTHERLY WINDS ALLOW SOME DRIER AIR TO ARRIVE
ACROSS THE AREA.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 10 AM EST THIS MORNING FOR INZ028-035-
036-043>047-051>056-060>065-067>072.
&&
$$
SYNOPSIS...NIELD
NEAR TERM...NIELD
SHORT TERM...NIELD
LONG TERM...PUMA
AVIATION...JP
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSINDIANAPOLIS
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
423 AM EST FRI DEC 5 2014
.UPDATE...
AVIATION SECTION UPDATED.
&&
.SYNOPSIS...
ISSUED AT 406 AM EST FRI DEC 5 2014
LOW PRESSURE WILL MOVE ALONG A FRONTAL ZONE NEAR THE OHIO RIVER
TODAY INTO SATURDAY...BRINGING WIDESPREAD RAINFALL TO CENTRAL
INDIANA. DENSE FOG WILL ALSO BE AN ISSUE THROUGH MIDDAY TODAY.
PRECIPITATION WILL END BY MIDDAY SATURDAY AS HIGH PRESSURE BUILDS
INTO THE AREA. ASIDE FROM A CHANCE OF RAIN ON MONDAY AS A WEAK
FRONTAL BOUNDARY PUSHES THROUGH THE REGION...DRY WEATHER CAN BE
EXPECTED FOR THE REMAINDER OF THE FORECAST PERIOD.
&&
.NEAR TERM /TODAY AND TONIGHT/...
ISSUED AT 406 AM EST FRI DEC 5 2014
DENSE FOG HAS DEVELOPED AND ADVECTED INTO THE AREA THIS
MORNING...AND PER HRRR VISIBILITY PROGS EXPECT IT TO PUSH A BIT
FURTHER NORTH AND EAST OVER THE NEXT COUPLE OF HOURS. VISIBILITIES
IN THIS AREA LOOK TO OFTEN BE ONE QUARTER MILE WITH A FEW AREAS OF
NEAR ZERO VISIBILITY. AS SUCH...HAVE ISSUED A DENSE FOG ADVISORY
IN COLLABORATION WITH SURROUNDING OFFICES...AND WILL KEEP THE
ADVISORY GOING UNTIL 15Z...WHEN PROGS SUGGEST VISIBILITY SHOULD
IMPROVE. THERE IS SOME CHANCE VISIBILITIES MAY IMPROVE EARLIER AS
RAINFALL DEVELOPS ACROSS THE SOUTHWEST...AND IF THIS BECOMES THE
CASE THE ADVISORY MAY BE ABLE TO DROP EARLY.
LOW PRESSURE WILL DEVELOP AND PUSH EASTWARD ALONG AN UNDULATING
FRONTAL ZONE TO OUR SOUTH TODAY...AND EXPECT WIDESPREAD RAINFALL
TO DEVELOP ACROSS CENTRAL INDIANA...ESPECIALLY THIS AFTERNOON.
WILL RAMP POPS UP GRADUALLY DURING THE MORNING TO 90 TO 100
PERCENT ACROSS THE ENTIRE AREA BY LATE AFTERNOON.
LATE AFTERNOON INTO THE OVERNIGHT...WHILE UPRIGHT INSTABILITY IS
NIL...SOME RELATIVELY STOUT FRONTOGENETIC FORCING WILL PUSH INTO
THE AREA...ALONG WITH SOME INSTABILITY IN THE FORM OF SATURATED
NEGATIVE EPV. ADDITIONALLY...FORECAST SOUNDINGS ACROSS THE
SOUTHERN FORECAST AREA SHOW LIFTED INDEX VALUES NEAR 0 TO 1 WITH A
PARCEL LIFTED FROM ROUGHLY 900 MB...AROUND THE TOP OF THE
INVERSION. ALL THIS IS TO SAY THAT A STRAY RUMBLE OF THUNDER
ACROSS THE FAR SOUTH CANNOT COMPLETELY BE RULED OUT...BUT IS LOW
PROBABILITY ENOUGH TO EXCLUDE FROM THE GRIDS UNTIL DEVELOPMENT
SAYS OTHERWISE.
POPS WILL REMAIN 90 TO 100 PERCENT THROUGHOUT THE NIGHT...BUT THE
MOST INTENSE OF THE RAINFALL APPEARS LIKELY TO OCCUR LATE
AFTERNOON THROUGH LATE EVENING WHEN THE MESOSCALE FORCING IS
STRONGEST. TOTAL RAINFALL AMOUNTS OF AROUND ONE INCH ACROSS THE
NORTH...TO AN INCH TO INCH AND A HALF ACROSS THE SOUTH APPEAR
LIKELY.
ON TEMPS...USED ADJUSTED RAW MODEL BLENDS AS THE RAW MODEL TEMPS
WILL LIKELY BEST CAPTURE WHAT SHOULD BE A VERY STRONG TEMPERATURE
GRADIENT ACROSS PORTIONS OF THE AREA TODAY AND TONIGHT. NONDIURNAL
TEMPERATURE PROGRESSION APPEARS LIKELY ACROSS THE FAR SOUTH
NEAREST THE LOW AND THE FRONTAL ZONE TODAY AND TONIGHT...WITH
HIGH TEMPERATURES FOR THE DATE POTENTIALLY REACHED NEAR MIDNIGHT.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
ISSUED AT 406 AM EST FRI DEC 5 2014
WHILE SOME PRECIP APPEARS LIKELY TO PERSIST INTO SATURDAY
MORNING...ESPECIALLY ACROSS THE EASTERN PORTIONS OF THE FORECAST
AREA...MODEL GUIDANCE IS IN GOOD AGREEMENT THAT DRY WEATHER WILL
RETURN TO THE AREA BY SATURDAY AFTERNOON...AND REMAIN SO THROUGH
THE REMAINDER OF THE SHORT TERM.
APPEARS THAT LOW LEVEL THERMAL PROFILES WILL REMAIN WARM ENOUGH
THROUGH THE END OF THE PRECIPITATION THAT NO FREEZING OR FROZEN
PRECIP IS ANTICIPATED.
ON TEMPS...MODEL CONSENSUS NUMBERS APPEARED REASONABLE THROUGHOUT
WITH A FEW MINOR TWEAKS...PER LOW LEVEL THICKNESS PROGS AND TEMPS.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
ISSUED AT 228 AM EST FRI DEC 5 2014
GENERALLY QUIET WEATHER WITH NEAR NORMAL TEMPERATURES LOOK IN
STORE DURING THIS PERIOD. THE ECMWF AND GFS HINT AT A COLD FRONTAL
PASSES ACROSS THE AREA ON MONDAY AS LOW PRESSURE MOVES THROUGH THE
GREAT LAKES. AT THIS TIME MOISTURE APPEARS LIMITED AS THE LOWER
LEVEL FLOW AHEAD OF THE COLD FRONT FAILS TO OPEN UP FROM THE
GULF. THUS HAVE INCLUDED SOME LOW CHC POPS FOR NOW AS WE CANNOT
RULE OUT A LIGHT PRECIPITATION EVENT.
COOL HIGH PRESSURE THEN BUILD ACROSS THE MISSISSIPPI AND OHIO
RIVER VALLEYS THROUGH THE REST OF THE PERIOD. ALOFT NORTHWEST FLOW
PERSISTS THROUGH MUCH OF THE NEXT WORK WEEK WITH LITTLE IN THE WAY
OF UPPER DYNAMICS PUSHING THROUGH THE OHIO VALLEY. BY THURSDAY AND
FRIDAY...REINFORCING RIDGING APPEARS TO BE BUILDING ACROSS THE
PLAINS STATES AND MISSISSIPPI VALLEY. THUS SHOULD CONTINUE THE
TREND OF DRY WEATHER FOR MUCH OF NEXT WEEK.
&&
.AVIATION /DISCUSSION FOR THE 050900Z IND TAF UPDATE/...
IFR TO LIFR CONDITIONS ARE EXPECTED AS THESE CONDITIONS ARE ONGOING
ACROSS THE TAF SITES. LITTLE IN THE WAY OF IMPROVEMENT IS EXPECTED
AS LOW PRESSURE OVER SOUTHERN PLAINS PUSHES TOWARD INDIANA ALONG A
WARM FRONT LINGERING ACROSS ILLINOIS AND INDIANA. ONGOING TIME
SECTIONS CONTINUE TO SUGGEST SATURATED LOWER LEVEL. NUMEROUS
LOCATIONS UPSTREAM...ALONG AND ON THE NORTH SIDE OF THE WARM FRONT CONTINUE
TO EXPERIENCE IFR TO LIFR CONDITIONS. THIS IS EXPECTED TO CONTINUE
FOR MUCH OF THE TAF PERIOD AS THIS SYSTEM PASSES.
/DISCUSSION FOR 050600Z TAF ISSUANCE/...
ISSUED AT 1135 PM EST THU DEC 4 2014
VERY POOR FLYING CONDITIONS EXPECTED FOR MUCH OF THE FORECAST
PERIOD.
SUB-IFR STRATUS DECK CONTINUES TO PROGRESS SLOWLY NORTHWARD LATE
THIS EVENING...AND IS EXPECTED TO ENCOMPASS BOTH KIND AND KLAF
WITHIN THE FIRST FEW HOURS OF THE FORECAST. EXPECT ALL TERMINALS TO
DROP TO NEAR OR BELOW 500FT PRIOR TO DAYBREAK AND REMAIN THERE ALL
DAY FRIDAY WITH A SATURATED COLUMN AND SHARP INVERSION IN THE NEAR
SURFACE LAYER.
WRF-NMM/ARW AND HRRR ALL SPREAD STEADY LIGHT RAIN NORTHEAST ACROSS
CENTRAL INDIANA DURING THE MORNING. HEAVIER CONVECTIVE RAINFALL
ARRIVES BY LATE AFTERNOON AS LOW PRESSURE TRACKS FROM THE OZARKS
INTO THE LOWER OHIO VALLEY. VISIBILITIES WILL FALL TO 1SM AND LOWER
WITHIN THE HEAVIER RAIN ALONG WITH CONTINUED CEILINGS JUST A FEW
HUNDRED FEET OFF THE GROUND. THE LOW WILL MOVE ALONG THE OHIO RIVER
FRIDAY EVENING WITH RAIN GRADUALLY DIMINISHING IN INTENSITY TOWARDS
THE END OF THE FORECAST PERIOD. LIFR CONDITIONS HOWEVER WILL PERSIST
THROUGH MUCH OF THE NIGHT. LIGHT SOUTHEAST WINDS WILL BACK TO
EASTERLY BY EARLY EVENING THEN NORTHEAST AS THE LOW PASSES BY TO THE
SOUTH.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 10 AM EST THIS MORNING FOR INZ028-035-
036-043>047-051>056-060>065-067>072.
&&
$$
SYNOPSIS...NIELD
NEAR TERM...NIELD
SHORT TERM...NIELD
LONG TERM...PUMA
AVIATION...RYAN
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSINDIANAPOLIS
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
406 AM EST FRI DEC 5 2014
.UPDATE...
THE SYNOPSIS...NEAR TERM AND SHORT TERM SECTIONS HAVE BEEN
UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 406 AM EST FRI DEC 5 2014
LOW PRESSURE WILL MOVE ALONG A FRONTAL ZONE NEAR THE OHIO RIVER
TODAY INTO SATURDAY...BRINGING WIDESPREAD RAINFALL TO CENTRAL
INDIANA. DENSE FOG WILL ALSO BE AN ISSUE THROUGH MIDDAY TODAY.
PRECIPITATION WILL END BY MIDDAY SATURDAY AS HIGH PRESSURE BUILDS
INTO THE AREA. ASIDE FROM A CHANCE OF RAIN ON MONDAY AS A WEAK
FRONTAL BOUNDARY PUSHES THROUGH THE REGION...DRY WEATHER CAN BE
EXPECTED FOR THE REMAINDER OF THE FORECAST PERIOD.
&&
.NEAR TERM /TODAY AND TONIGHT/...
ISSUED AT 406 AM EST FRI DEC 5 2014
DENSE FOG HAS DEVELOPED AND ADVECTED INTO THE AREA THIS
MORNING...AND PER HRRR VISIBILITY PROGS EXPECT IT TO PUSH A BIT
FURTHER NORTH AND EAST OVER THE NEXT COUPLE OF HOURS. VISIBILITIES
IN THIS AREA LOOK TO OFTEN BE ONE QUARTER MILE WITH A FEW AREAS OF
NEAR ZERO VISIBILITY. AS SUCH...HAVE ISSUED A DENSE FOG ADVISORY
IN COLLABORATION WITH SURROUNDING OFFICES...AND WILL KEEP THE
ADVISORY GOING UNTIL 15Z...WHEN PROGS SUGGEST VISIBILTY SHOULD
IMPROVE. THERE IS SOME CHANCE VISIBILITIES MAY IMPROVE EARLIER AS
RAINFALL DEVELOPS ACROSS THE SOUTHWEST...AND IF THIS BECOMES THE
CASE THE ADVISORY MAY BE ABLE TO DROP EARLY.
LOW PRESSURE WILL DEVELOP AND PUSH EASTWARD ALONG AN UNDULATING
FRONTAL ZONE TO OUR SOUTH TODAY...AND EXPECT WIDESPREAD RAINFALL
TO DEVELOP ACROSS CENTRAL INDIANA...ESPECIALLY THIS AFTERNOON.
WILL RAMP POPS UP GRADUALLY DURING THE MORNING TO 90 TO 100
PERCENT ACROSS THE ENTIRE AREA BY LATE AFTERNOON.
LATE AFTERNOON INTO THE OVERNIGHT...WHILE UPRIGHT INSTABILITY IS
NIL...SOME RELATIVELY STOUT FRONTOGENETIC FORCING WILL PUSH INTO
THE AREA...ALONG WITH SOME INSTABILITY IN THE FORM OF SATURATED
NEGATIVE EPV. ADDITIONALLY...FORECAST SOUNDINGS ACROSS THE
SOUTHERN FORECAST AREA SHOW LIFTED INDEX VALUES NEAR 0 TO 1 WITH A
PARCEL LIFTED FROM ROUGHLY 900 MB...AROUND THE TOP OF THE
INVERSION. ALL THIS IS TO SAY THAT A STRAY RUMBLE OF THUNDER
ACROSS THE FAR SOUTH CANNOT COMPLETELY BE RULED OUT...BUT IS LOW
PROBABILITY ENOUGH TO EXCLUDE FROM THE GRIDS UNTIL DEVELOPMENT
SAYS OTHERWISE.
POPS WILL REMAIN 90 TO 100 PERCENT THROUGHOUT THE NIGHT...BUT THE
MOST INTENSE OF THE RAINFALL APPEARS LIKELY TO OCCUR LATE
AFTERNOON THROUGH LATE EVENING WHEN THE MESOSCALE FORCING IS
STRONGEST. TOTAL RAINFALL AMOUNTS OF AROUND ONE INCH ACROSS THE
NORTH...TO AN INCH TO INCH AND A HALF ACROSS THE SOUTH APPEAR
LIKELY.
ON TEMPS...USED ADJUSTED RAW MODEL BLENDS AS THE RAW MODEL TEMPS
WILL LIKELY BEST CAPTURE WHAT SHOULD BE A VERY STRONG TEMPERATURE
GRADIENT ACROSS PORTIONS OF THE AREA TODAY AND TONIGHT. NONDIURNAL
TEMPERATURE PROGRESSION APPEARS LIKELY ACROSS THE FAR SOUTH
NEAREST THE LOW AND THE FRONTAL ZONE TODAY AND TONIGHT...WITH
HIGH TEMPERATURES FOR THE DATE POTENTIALLY REACHED NEAR MIDNIGHT.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
ISSUED AT 406 AM EST FRI DEC 5 2014
WHILE SOME PRECIP APPEARS LIKELY TO PERSIST INTO SATURDAY
MORNING...ESPECIALLY ACROSS THE EASTERN PORTIONS OF THE FORECAST
AREA...MODEL GUIDANCE IS IN GOOD AGREEMENT THAT DRY WEATHER WILL
RETURN TO THE AREA BY SATURDAY AFTERNOON...AND REMAIN SO THROUGH
THE REMAINDER OF THE SHORT TERM.
APPEARS THAT LOW LEVEL THERMAL PROFILES WILL REMAIN WARM ENOUGH
THROUGH THE END OF THE PRECIPITATION THAT NO FREEZING OR FROZEN
PRECIP IS ANTICIPATED.
ON TEMPS...MODEL CONSENSUS NUMBERS APPEARED REASONABLE THROUGHOUT
WITH A FEW MINOR TWEAKS...PER LOW LEVEL THICKNESS PROGS AND TEMPS.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
ISSUED AT 228 AM EST FRI DEC 5 2014
GENERALLY QUIET WEATHER WITH NEAR NORMAL TEMPERATURES LOOK IN
STORE DURING THIS PERIOD. THE ECMWF AND GFS HINT AT A COLD FRONTAL
PASSES ACROSS THE AREA ON MONDAY AS LOW PRESSURE MOVES THROUGH THE
GREAT LAKES. AT THIS TIME MOISTURE APPEARS LIMITED AS THE LOWER
LEVEL FLOW AHEAD OF THE COLD FRONT FAILS TO OPEN UP FROM THE
GULF. THUS HAVE INCLUDED SOME LOW CHC POPS FOR NOW AS WE CANNOT
RULE OUT A LIGHT PRECIPITATION EVENT.
COOL HIGH PRESSURE THEN BUILD ACROSS THE MISSISSIPPI AND OHIO
RIVER VALLEYS THROUGH THE REST OF THE PERIOD. ALOFT NORTHWEST FLOW
PERSISTS THROUGH MUCH OF THE NEXT WORK WEEK WITH LITTLE IN THE WAY
OF UPPER DYNAMICS PUSHING THROUGH THE OHIO VALLEY. BY THURSDAY AND
FRIDAY...REINFORCING RIDGING APPEARS TO BE BUILDING ACROSS THE
PLAINS STATES AND MISSISSIPPI VALLEY. THUS SHOULD CONTINUE THE
TREND OF DRY WEATHER FOR MUCH OF NEXT WEEK.
&&
.AVIATION /DISCUSSION FOR 050600Z TAF ISSUANCE/...
ISSUED AT 1135 PM EST THU DEC 4 2014
VERY POOR FLYING CONDITIONS EXPECTED FOR MUCH OF THE FORECAST
PERIOD.
SUB-IFR STRATUS DECK CONTINUES TO PROGRESS SLOWLY NORTHWARD LATE
THIS EVENING...AND IS EXPECTED TO ENCOMPASS BOTH KIND AND KLAF
WITHIN THE FIRST FEW HOURS OF THE FORECAST. EXPECT ALL TERMINALS TO
DROP TO NEAR OR BELOW 500FT PRIOR TO DAYBREAK AND REMAIN THERE ALL
DAY FRIDAY WITH A SATURATED COLUMN AND SHARP INVERSION IN THE NEAR
SURFACE LAYER.
WRF-NMM/ARW AND HRRR ALL SPREAD STEADY LIGHT RAIN NORTHEAST ACROSS
CENTRAL INDIANA DURING THE MORNING. HEAVIER CONVECTIVE RAINFALL
ARRIVES BY LATE AFTERNOON AS LOW PRESSURE TRACKS FROM THE OZARKS
INTO THE LOWER OHIO VALLEY. VISIBILITIES WILL FALL TO 1SM AND LOWER
WITHIN THE HEAVIER RAIN ALONG WITH CONTINUED CEILINGS JUST A FEW
HUNDRED FEET OFF THE GROUND. THE LOW WILL MOVE ALONG THE OHIO RIVER
FRIDAY EVENING WITH RAIN GRADUALLY DIMINISHING IN INTENSITY TOWARDS
THE END OF THE FORECAST PERIOD. LIFR CONDITIONS HOWEVER WILL PERSIST
THROUGH MUCH OF THE NIGHT. LIGHT SOUTHEAST WINDS WILL BACK TO
EASTERLY BY EARLY EVENING THEN NORTHEAST AS THE LOW PASSES BY TO THE
SOUTH.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 10 AM EST THIS MORNING FOR INZ028-035-
036-043>047-051>056-060>065-067>072.
&&
$$
SYNOPSIS...NIELD
NEAR TERM...NIELD
SHORT TERM...NIELD
LONG TERM...PUMA
AVIATION...RYAN
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT:
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WWW.TWITTER.COM/NWSINDIANAPOLIS
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AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
240 AM EST FRI DEC 5 2014
.UPDATE...
THE LONG TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 336 PM EST THU DEC 4 2014
RAIN CHANCES WILL BE INCREASING OVERNIGHT TONIGHT AHEAD OF A
SOUTHERN PLAINS SURFACE LOW PRESSURE SYSTEM AND IN A UPGLIDE REGIME.
THIS SYSTEM WILL LIFT NORTHEAST ACROSS SOUTHERN INDIANA FRIDAY NIGHT
BRINGING WIDESPREAD RAIN TO CENTRAL INDIANA FRIDAY AND FRIDAY NIGHT.
THEN...HIGH PRESSURE WILL ALLOW FOR MOSTLY DRY CONDITIONS EXCEPT FOR
RAIN CHANCES MAINLY EARLY SATURDAY IN THE WAKE OF THE AFOREMENTIONED
LOW PRESSURE SYSTEM AND MONDAY ALONG AND AHEAD OF A NORTHWEST QUICK
MOVING SYSTEM.
TEMPERATURES WILL BE NEAR NORMAL WITH AFTERNOON HIGHS MOSTLY IN 30S
AND 40S...ALTHOUGH SOUTHERN PARTS OF CENTRAL INDIANA COULD SEE LOWER
50S ON FRIDAY.
&&
.NEAR TERM /REST OF TONIGHT/...
ISSUED AT 959 PM EST THU DEC 4 2014
RADAR IS PRETTY QUIET AT THE MOMENT AS FORCING AS WANED THIS
EVENING. HAVE THUS REMOVED POPS FOR MUCH OF THE AREA FOR THE MOMENT.
FORCING WILL GRADUALLY INCREASE OVERNIGHT...BUT DECENT FORCING DOES
NOT ARRIVE UNTIL AFTER 12Z. THUS PUT HIGHEST POPS JUST BEFORE 12Z
AND KEPT THEM IN THE CHANCE CATEGORY LIKE EARLIER FORECAST HAD.
DID ADD DRIZZLE MENTION THIS EVENING INTO THE EARLY OVERNIGHT WHERE
POPS ARE BELOW 20 PERCENT. WITH MOISTURE GRADUALLY INCREASING DID
ADD SOME PATCHY FOG OVERNIGHT. TEMPERATURES LOOK GOOD SO ONLY MADE
MINOR TWEAKS.
PREVIOUS DISCUSSION FOLLOWS...
MODELS IN GOOD AGREEMENT THAT ISENTROPIC LIFT WILL INCREASE AGAIN
OVERNIGHT. CONDENSATION PRESSURE DEFICITS AND SOUNDINGS SUGGEST THE
BEST CHANCE OF RAIN WILL BE ALONG AND SOUTH OF INTERSTATE 70.
RAP13 SOUNDINGS AND BUFKIT SUGGEST ANY LINGERING LIGHT RAIN IN THE
WARM AIR ADVECTION PATTERN SHOULD BE ALL OR MOSTLY RAIN TONIGHT. DO
NOT THINK THE TEMPERATURE WILL DROP TO 32 DEGREES AT MOST OR ALL
LOCALES WITH LIGHT SOUTHEAST WINDS AND CLOUDY SKIES. PREFER THE
WARMER 12Z GFS AND ECMWF MOS. HOWEVER...WILL HAVE TO KEEP A CLOSE
EYE ON OBSERVATIONS NORTH OF 70 AS SOUNDINGS SUGGEST SOME POTENTIAL
FOR EVAPORATIVE COOLING EARLY ON. WENT WITH SMALL CHANCE POPS NORTH
AND GOOD CHANCE POPS SOUTHWEST AND MOSTLY OVERNIGHT.
LAST LOOK AT OBSERVATIONS INCLUDING THE MESO NETWORK SUGGESTS A NEED
TO CONTINUE WITH A MIX FOR THE REST OF THE AFTERNOON NORTH OF
INDIANAPOLIS. SO...WILL NEED TO ADD A PRE-FIRST PERIOD.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY/...
ISSUED AT 336 PM EST THU DEC 4 2014
FORECAST FOCUS WILL BE ON TIMING...COVERAGE AND POPS ASSOCIATED WITH
EXPECTED MODERATE RAINFALL FRIDAY AND FRIDAY NIGHT.
MODELS HAVE SOME TIMING DIFFERENCES REGARDING TIMING OF A SURFACE
SYSTEM AS IT MOVES ACROSS THE AREA FRIDAY NIGHT. THE ECMWF AND ITS
ENSEMBLE MEANS CONTINUES TO BE THE SLOWEST WITH THE SURFACE WAVE
COMPARED TO THE OTHER MODELS AND GEFS. HOWEVER...THE GEFS ENSEMBLE
MEMBERS WERE NOT WELL CLUSTERED. SO...PREFER A MODEL BLEND WHICH
WILL BRING THE SURFACE WAVE TO SOUTHWESTERN INDIANA AT 06Z
SATURDAY AND SOUTHWESTERN OHIO OR NORTHERN KENTUCKY 12Z SATURDAY.
EVEN THE QUICKER 12Z GFS HOLDS ON TO SOME QPF ACROSS OUR EAST ON
SATURDAY MORNING WITH THE ECMWF HAVING IT ACROSS OUR WHOLE
FORECAST AREA SATURDAY MORNING. WENT CLOSER TO THE EURO WITH SOME
ADJUSTMENTS POSSIBLE AS SATURDAY GETS CLOSER. THE HEAVIEST RAINS
SHOULD SPREAD FROM SOUTHWEST TO NORTHEAST OVER THE FORECAST AREA
ON FRIDAY AND CONTINUE FRIDAY NIGHT. COULD SEE AN INCH TO AN INCH
AND A HALF STORM TOTAL RAIN...WHICH SUCH GOOD LIFT AND DEEP
MOISTURE.
LATE SATURDAY THROUGH SUNDAY SHOULD BE DRY WITH HIGH PRESSURE
BUILDING IN FROM THE NORTHWEST ALONG WITH CLEARING SKIES.
PREFER MODEL MIX WITH SLIGHTLY ABOVE NORMAL 12Z NAM AND ECMWF
TEMPERATURES ON FRIDAY WITH THE WARM AIR ADVECTION AND DESPITE THE
RAIN. AFTER THAT...BLEND LOOKS GOOD WITH NEAR NORMAL TEMPERATURES.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
ISSUED AT 228 AM EST FRI DEC 5 2014
GENERALLY QUIET WEATHER WITH NEAR NORMAL TEMPERATURES LOOK IN
STORE DURING THIS PERIOD. THE ECMWF AND GFS HINT AT A COLD FRONTAL
PASSES ACROSS THE AREA ON MONDAY AS LOW PRESSURE MOVES THROUGH THE
GREAT LAKES. AT THIS TIME MOISTURE APPEARS LIMITED AS THE LOWER
LEVEL FLOW AHEAD OF THE COLD FRONT FAILS TO OPEN UP FROM THE
GULF. THUS HAVE INCLUDED SOME LOW CHC POPS FOR NOW AS WE CANNOT
RULE OUT A LIGHT PRECIPITATION EVENT.
COOL HIGH PRESSURE THEN BUILD ACROSS THE MISSISSIPPI AND OHIO
RIVER VALLEYS THROUGH THE REST OF THE PERIOD. ALOFT NORTHWEST FLOW
PERSISTS THROUGH MUCH OF THE NEXT WORK WEEK WITH LITTLE IN THE WAY
OF UPPER DYNAMICS PUSHING THROUGH THE OHIO VALLEY. BY THURSDAY AND
FRIDAY...REINFORCING RIDGING APPEARS TO BE BUILDING ACROSS THE
PLAINS STATES AND MISSISSIPPI VALLEY. THUS SHOULD CONTINUE THE
TREND OF DRY WEATHER FOR MUCH OF NEXT WEEK.
&&
.AVIATION /DISCUSSION FOR 050600Z TAF ISSUANCE/...
ISSUED AT 1135 PM EST THU DEC 4 2014
VERY POOR FLYING CONDITIONS EXPECTED FOR MUCH OF THE FORECAST
PERIOD.
SUB-IFR STRATUS DECK CONTINUES TO PROGRESS SLOWLY NORTHWARD LATE
THIS EVENING...AND IS EXPECTED TO ENCOMPASS BOTH KIND AND KLAF
WITHIN THE FIRST FEW HOURS OF THE FORECAST. EXPECT ALL TERMINALS TO
DROP TO NEAR OR BELOW 500FT PRIOR TO DAYBREAK AND REMAIN THERE ALL
DAY FRIDAY WITH A SATURATED COLUMN AND SHARP INVERSION IN THE NEAR
SURFACE LAYER.
WRF-NMM/ARW AND HRRR ALL SPREAD STEADY LIGHT RAIN NORTHEAST ACROSS
CENTRAL INDIANA DURING THE MORNING. HEAVIER CONVECTIVE RAINFALL
ARRIVES BY LATE AFTERNOON AS LOW PRESSURE TRACKS FROM THE OZARKS
INTO THE LOWER OHIO VALLEY. VISIBILITIES WILL FALL TO 1SM AND LOWER
WITHIN THE HEAVIER RAIN ALONG WITH CONTINUED CEILINGS JUST A FEW
HUNDRED FEET OFF THE GROUND. THE LOW WILL MOVE ALONG THE OHIO RIVER
FRIDAY EVENING WITH RAIN GRADUALLY DIMINISHING IN INTENSITY TOWARDS
THE END OF THE FORECAST PERIOD. LIFR CONDITIONS HOWEVER WILL PERSIST
THROUGH MUCH OF THE NIGHT. LIGHT SOUTHEAST WINDS WILL BACK TO
EASTERLY BY EARLY EVENING THEN NORTHEAST AS THE LOW PASSES BY TO THE
SOUTH.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...MK
NEAR TERM...MK/50
SHORT TERM...MK
LONG TERM....PUMA
AVIATION...RYAN
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSINDIANAPOLIS
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1135 PM EST THU DEC 4 2014
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 336 PM EST THU DEC 4 2014
RAIN CHANCES WILL BE INCREASING OVERNIGHT TONIGHT AHEAD OF A
SOUTHERN PLAINS SURFACE LOW PRESSURE SYSTEM AND IN A UPGLIDE REGIME.
THIS SYSTEM WILL LIFT NORTHEAST ACROSS SOUTHERN INDIANA FRIDAY NIGHT
BRINGING WIDESPREAD RAIN TO CENTRAL INDIANA FRIDAY AND FRIDAY NIGHT.
THEN...HIGH PRESSURE WILL ALLOW FOR MOSTLY DRY CONDITIONS EXCEPT FOR
RAIN CHANCES MAINLY EARLY SATURDAY IN THE WAKE OF THE AFOREMENTIONED
LOW PRESSURE SYSTEM AND MONDAY ALONG AND AHEAD OF A NORTHWEST QUICK
MOVING SYSTEM.
TEMPERATURES WILL BE NEAR NORMAL WITH AFTERNOON HIGHS MOSTLY IN 30S
AND 40S...ALTHOUGH SOUTHERN PARTS OF CENTRAL INDIANA COULD SEE LOWER
50S ON FRIDAY.
&&
.NEAR TERM /REST OF TONIGHT/...
ISSUED AT 959 PM EST THU DEC 4 2014
RADAR IS PRETTY QUIET AT THE MOMENT AS FORCING AS WANED THIS
EVENING. HAVE THUS REMOVED POPS FOR MUCH OF THE AREA FOR THE MOMENT.
FORCING WILL GRADUALLY INCREASE OVERNIGHT...BUT DECENT FORCING DOES
NOT ARRIVE UNTIL AFTER 12Z. THUS PUT HIGHEST POPS JUST BEFORE 12Z
AND KEPT THEM IN THE CHANCE CATEGORY LIKE EARLIER FORECAST HAD.
DID ADD DRIZZLE MENTION THIS EVENING INTO THE EARLY OVERNIGHT WHERE
POPS ARE BELOW 20 PERCENT. WITH MOISTURE GRADUALLY INCREASING DID
ADD SOME PATCHY FOG OVERNIGHT. TEMPERATURES LOOK GOOD SO ONLY MADE
MINOR TWEAKS.
PREVIOUS DISCUSSION FOLLOWS...
MODELS IN GOOD AGREEMENT THAT ISENTROPIC LIFT WILL INCREASE AGAIN
OVERNIGHT. CONDENSATION PRESSURE DEFICITS AND SOUNDINGS SUGGEST THE
BEST CHANCE OF RAIN WILL BE ALONG AND SOUTH OF INTERSTATE 70.
RAP13 SOUNDINGS AND BUFKIT SUGGEST ANY LINGERING LIGHT RAIN IN THE
WARM AIR ADVECTION PATTERN SHOULD BE ALL OR MOSTLY RAIN TONIGHT. DO
NOT THINK THE TEMPERATURE WILL DROP TO 32 DEGREES AT MOST OR ALL
LOCALES WITH LIGHT SOUTHEAST WINDS AND CLOUDY SKIES. PREFER THE
WARMER 12Z GFS AND ECMWF MOS. HOWEVER...WILL HAVE TO KEEP A CLOSE
EYE ON OBSERVATIONS NORTH OF 70 AS SOUNDINGS SUGGEST SOME POTENTIAL
FOR EVAPORATIVE COOLING EARLY ON. WENT WITH SMALL CHANCE POPS NORTH
AND GOOD CHANCE POPS SOUTHWEST AND MOSTLY OVERNIGHT.
LAST LOOK AT OBSERVATIONS INCLUDING THE MESO NETWORK SUGGESTS A NEED
TO CONTINUE WITH A MIX FOR THE REST OF THE AFTERNOON NORTH OF
INDIANAPOLIS. SO...WILL NEED TO ADD A PRE-FIRST PERIOD.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY/...
ISSUED AT 336 PM EST THU DEC 4 2014
FORECAST FOCUS WILL BE ON TIMING...COVERAGE AND POPS ASSOCIATED WITH
EXPECTED MODERATE RAINFALL FRIDAY AND FRIDAY NIGHT.
MODELS HAVE SOME TIMING DIFFERENCES REGARDING TIMING OF A SURFACE
SYSTEM AS IT MOVES ACROSS THE AREA FRIDAY NIGHT. THE ECMWF AND ITS
ENSEMBLE MEANS CONTINUES TO BE THE SLOWEST WITH THE SURFACE WAVE
COMPARED TO THE OTHER MODELS AND GEFS. HOWEVER...THE GEFS ENSEMBLE
MEMBERS WERE NOT WELL CLUSTERED. SO...PREFER A MODEL BLEND WHICH
WILL BRING THE SURFACE WAVE TO SOUTHWESTERN INDIANA AT 06Z
SATURDAY AND SOUTHWESTERN OHIO OR NORTHERN KENTUCKY 12Z SATURDAY.
EVEN THE QUICKER 12Z GFS HOLDS ON TO SOME QPF ACROSS OUR EAST ON
SATURDAY MORNING WITH THE ECMWF HAVING IT ACROSS OUR WHOLE
FORECAST AREA SATURDAY MORNING. WENT CLOSER TO THE EURO WITH SOME
ADJUSTMENTS POSSIBLE AS SATURDAY GETS CLOSER. THE HEAVIEST RAINS
SHOULD SPREAD FROM SOUTHWEST TO NORTHEAST OVER THE FORECAST AREA
ON FRIDAY AND CONTINUE FRIDAY NIGHT. COULD SEE AN INCH TO AN INCH
AND A HALF STORM TOTAL RAIN...WHICH SUCH GOOD LIFT AND DEEP
MOISTURE.
LATE SATURDAY THROUGH SUNDAY SHOULD BE DRY WITH HIGH PRESSURE
BUILDING IN FROM THE NORTHWEST ALONG WITH CLEARING SKIES.
PREFER MODEL MIX WITH SLIGHTLY ABOVE NORMAL 12Z NAM AND ECMWF
TEMPERATURES ON FRIDAY WITH THE WARM AIR ADVECTION AND DESPITE THE
RAIN. AFTER THAT...BLEND LOOKS GOOD WITH NEAR NORMAL TEMPERATURES.
&&
.LONG TERM /SUNDAY NIGHT THROUGH NEXT THURSDAY/...
ISSUED AT 245 PM EST THU DEC 4 2014
ENSEMBLES IN GOOD AGREEMENT IN DEPICTING A PROGRESSIVE UPPER PATTERN
DURING THIS PERIOD. AN UPPER TROUGH IS EXPECTED TO DROP SOUTHEAST
ACROSS THE AREA AROUND MONDAY. IN THE WAKE OF THIS SYSTEM...UPPER
RIDGING IS PROGGED TO BUILD THROUGH THE PLAINS BY THE MIDDLE OF NEXT
WEEK.
WILL KEEP SOME CHANCE POPS FOR LIGHT RAIN GOING ON MONDAY IN
ASSOCIATION WITH THE PASSAGE OF THE UPPER TROUGH. AT THIS
POINT...SYSTEM DOESN/T LOOK IMPRESSIVE WITH ENSEMBLES SUGGESTING
LIGHT QPF FOR THE MOST PART.
WILL GO WITH A DRY FORECAST FOR THE REST OF THE EXTENDED AS THE
UPPER RIDGE BUILDS INTO THE PLAINS.
&&
.AVIATION /DISCUSSION FOR 050600Z TAF ISSUANCE/...
ISSUED AT 1135 PM EST THU DEC 4 2014
VERY POOR FLYING CONDITIONS EXPECTED FOR MUCH OF THE FORECAST
PERIOD.
SUB-IFR STRATUS DECK CONTINUES TO PROGRESS SLOWLY NORTHWARD LATE
THIS EVENING...AND IS EXPECTED TO ENCOMPASS BOTH KIND AND KLAF
WITHIN THE FIRST FEW HOURS OF THE FORECAST. EXPECT ALL TERMINALS TO
DROP TO NEAR OR BELOW 500FT PRIOR TO DAYBREAK AND REMAIN THERE ALL
DAY FRIDAY WITH A SATURATED COLUMN AND SHARP INVERSION IN THE NEAR
SURFACE LAYER.
WRF-NMM/ARW AND HRRR ALL SPREAD STEADY LIGHT RAIN NORTHEAST ACROSS
CENTRAL INDIANA DURING THE MORNING. HEAVIER CONVECTIVE RAINFALL
ARRIVES BY LATE AFTERNOON AS LOW PRESSURE TRACKS FROM THE OZARKS
INTO THE LOWER OHIO VALLEY. VISIBILITIES WILL FALL TO 1SM AND LOWER
WITHIN THE HEAVIER RAIN ALONG WITH CONTINUED CEILINGS JUST A FEW
HUNDRED FEET OFF THE GROUND. THE LOW WILL MOVE ALONG THE OHIO RIVER
FRIDAY EVENING WITH RAIN GRADUALLY DIMINISHING IN INTENSITY TOWARDS
THE END OF THE FORECAST PERIOD. LIFR CONDITIONS HOWEVER WILL PERSIST
THROUGH MUCH OF THE NIGHT. LIGHT SOUTHEAST WINDS WILL BACK TO
EASTERLY BY EARLY EVENING THEN NORTHEAST AS THE LOW PASSES BY TO THE
SOUTH.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...MK
NEAR TERM...MK/50
SHORT TERM...MK
LONG TERM....JAS
AVIATION...RYAN
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSINDIANAPOLIS
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS GOODLAND KS
400 PM MST FRI DEC 5 2014
.SHORT TERM...(THIS AFTERNOON THROUGH SATURDAY)
ISSUED AT 1246 PM MST FRI DEC 5 2014
LATEST WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOW RIDGING
BUILDING ACROSS INTER-MOUNTAIN WEST...WITH A SHORTWAVE TROUGH
CENTERED OVER EASTERN KANSAS. SUBSIDENCE/CLEARING IS IN PLACE
OVER OUR CWA. AT THE THE SURFACE...PRE FRONTAL LOW PRESSURE IS IN
PLACE ACROSS KANSAS AND EASTERN COLORADO WITH A WEAK COLD FRONT
OVER SOUTHERN NEBRASKA. AHEAD OF THE COLD FRONT TEMPERATURES HAVE
WARMED TO NEAR 60 DEGREES OVER MUCH OF THE CWA WITH A WELL MIXED
AIR MASS AND SURFACE TROUGH IN PLACE.
DRY FORECAST CONTINUES THROUGH SATURDAY AFTERNOON AS RIDGE
TRANSITIONS EASTWARD...AND SUBSIDENT/DRY AIR MASS LINGERS.
THIS AFTERNOON-TONIGHT...THE COLD FRONT OVER NEBRASKA WILL DROP
SOUTH THIS LATE THIS AFTERNOON AND EVENING WITH SURFACE HIGH
PRESSURE SETTLING IN FROM THE NORTHERN PLAINS. A COOLER/DRIER AIR
MASS WILL ACCOMPANY THIS HIGH PRESSURE SYSTEM...RETURNING
OVERNIGHT LOWS TO SEASONAL VALUES AROUND 20F. NAM/SREF CONTINUE TO
HINT AT SURFACE RH VALUES APPROACHING SATURATION AND POSSIBLE FOG
DEVELOPMENT. SOUNDINGS INDICATE THIS WILL BE VERY SHALLOW MOIST
LAYER...AND A DRY BL WILL GENERALLY INHIBIT FOG/STRATUS
DEVELOPMENT TONIGHT. HRRR/RAP CURRENTLY SHOWING NO FOG DEVELOPMENT
OVER OUR CWA. WHILE WE COULD SEE SOME SHALLOW FOG DEVELOPMENT...AT
THIS POINT CONFIDENCE IS JUST TOO LOW TO ADD.
SATURDAY...SHORTWAVE RIDING WILL TRANSITION THROUGH THE PLAINS ON
SATURDAY...WITH A SHORTWAVE TROUGH MOVING OUT OF THE GREAT BASIN
TOWARDS THE CENTRAL ROCKIES SATURDAY AFTERNOON. SW FLOW ALOFT WILL
DEVELOP BY SATURDAY AFTERNOON BETWEEN THESE FEATURES...WITH
INCREASING MID TO HIGH CLOUD COVER THROUGH THE DAY FROM THE WEST
TO THE EAST. LEE TROUGH AND SOUTHERLY FLOW WILL DEVELOP IN
RESPONSE TO THIS SHIFT IN FLOW ALOFT...SUPPORTING WAA ACROSS OUR
CWA AS THE SURFACE HIGH RETREATS EASTWARD.
NOT A LOT OF CONFIDENCE IN WHICH WILL WIN OUT: WAA WITH SOUTHERLY
FLOW OR LIMITED DIURNAL HEATING DUE TO INCREASING CLOUD COVER. I
ONLY MADE MINOR ADJUSTMENTS TO HIGH TEMP FORECAST...WHICH HAS
HIGHS NEAR 50 IN THE WEST AND THE MID 40S IN THE EAST. I COULD SEE
LOCATIONS IN THE WEST APPROACHING THE MID 50S IF CLOUD COVER HAS
MINIMAL IMPACT AND WE ACHIEVE FULL DAYTIME MIXING.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 222 PM MST FRI DEC 5 2014
AN UPPER TROUGH WILL MOVE INTO THE CENTRAL PLAINS SATURDAY NIGHT
FOLLOWED BY NORTHWEST FLOW SUNDAY. A RIDGE WILL MOVE EAST FROM THE
ROCKIES AND INTO THE PLAINS MONDAY. A SURFACE TROUGH WILL BE OVER
EASTERN COLORADO SATURDAY NIGHT AND THEN SHIFT EAST SUNDAY. SURFACE
HIGH PRESSURE WILL MOVE INTO THE CENTRAL PLAINS SUNDAY AND MONDAY.
THE UPPER TROUGH THAT COMES THROUGH THE FA SATURDAY NIGHT WILL BE
LACKING FOR MOISTURE. MOISTURE IMPROVES SOME AS THE SYSTEM EXITS
THE FAR EASTERN FA SUNDAY MORNING. FORECAST SOUNDINGS ACROSS THE FA
SATURDAY NIGHT SHOW CLOUD BASES FROM 8 TO 11KFT. FORECAST SOUNDINGS
SHOW SATURATION NEAR THE SURFACE EAST OF THE COLORADO LINE FOR
STRATUS/FOG AND LIGHT DRIZZLE WITH SURFACE TEMPERATURES ABOVE
FREEZING. SUBSIDENCE MOVES INTO THE FA LATE SUNDAY MORNING AND
CONTINUES THROUGH MONDAY. CONSEQUENTLY POPS WILL BE NIL FROM
SATURDAY NIGHT THROUGH MONDAY.
MIN TEMPERATURES SATURDAY AND SUNDAY NIGHTS WILL VARY FROM THE UPPER
20S TO AROUND 30. MAX TEMPERATURES SUNDAY SHOULD RANGE FROM 45 TO
50. MAX TEMPERATURES MONDAY SHOULD WARM TO THE MID AND UPPER 50S.
IN THE EXTENDED...(MONDAY NIGHT THROUGH FRIDAY)...A RIDGE WILL
PERSIST OVER THE CENTRAL PLAINS THROUGH THURSDAY AND THEN SHIFT EAST
FRIDAY WITH ZONAL FLOW EAST OF THE ROCKIES. SURFACE HIGH PRESSURE
WILL CONTINUE OVER THE CENTRAL PLAINS THROUGH TUESDAY. A TROUGH
MOVES INTO EASTERN COLORADO THURSDAY AND FRIDAY AS HIGH PRESSURE
DRIFTS EAST.
THE GFS BRINGS A SHORTWAVE THROUGH TUESDAY NIGHT WHILE THE ECMWF
KEEPS IT MUCH FURTHER NORTH. ALSO GFS SOUNDINGS SHOW VERY SHALLOW
MOISTURE WITH THE SYSTEM. FOR NOW WILL KEEP SILENT POPS FOR TUESDAY
NIGHT. AS A RESULT THE ENTIRE EXTENDED FORECAST WILL BE DRY WITH NO
OTHER SIGNIFICANT FORCING FOR THE REMAINING PERIODS.
MAX TEMPERATURES WILL VARY FROM THE MID 50S TO THE MID AND UPPER 50S
THURSDAY AND FRIDAY. MIN TEMPERATURES WILL COOL TO THE UPPER 20S TO
AROUND 30.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 400 PM MST FRI DEC 5 2014
FOR KGLD AND KMCK...VFR THROUGH THE PERIOD. SFC HIGH CURRENTLY
INFLUENCING THE AREAS WEATHER WILL SLOWLY MOVE EAST OVERNIGHT WITH
LOW PRESSURE DEEPENING ALONG THE FRONT RANGE. THE PRESSURE
GRADIENT BETWEEN THE TWO WILL SLOWLY STRENGTHEN DURING THE DAY
SATURDAY. LIGHT NORTH WINDS AT BOTH TERMINALS WILL BECOME
LIGHT/VARIABLE SHORTLY AFTER 06Z AND CONTINUE THROUGH ROUGHLY 15Z
ON THE BACKSIDE OF THE SFC HIGH SOUTHEAST WINDS SLOWLY INCREASE
DURING THE DAY WITH GUSTS AROUND 22KTS AT KGLD BY 20Z...CONTINUING
THROUGH THE REST OF THE TAF PERIOD. AT KMCK ONLY 10KT WINDS FROM
THE SOUTHEAST EXPECTED AFTER 21Z. MID AND HIGH CLOUDS INCREASE
FROM THE SOUTHWEST AFTER 17Z.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...FS
AVIATION...99
AREA FORECAST DISCUSSION
NWS GOODLAND KS
223 PM MST FRI DEC 5 2014
.SHORT TERM...(THIS AFTERNOON THROUGH SATURDAY)
ISSUED AT 1246 PM MST FRI DEC 5 2014
LATEST WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOW RIDGING
BUILDING ACROSS INTER-MOUNTAIN WEST...WITH A SHORTWAVE TROUGH
CENTERED OVER EASTERN KANSAS. SUBSIDENCE/CLEARING IS IN PLACE
OVER OUR CWA. AT THE THE SURFACE...PRE FRONTAL LOW PRESSURE IS IN
PLACE ACROSS KANSAS AND EASTERN COLORADO WITH A WEAK COLD FRONT
OVER SOUTHERN NEBRASKA. AHEAD OF THE COLD FRONT TEMPERATURES HAVE
WARMED TO NEAR 60 DEGREES OVER MUCH OF THE CWA WITH A WELL MIXED
AIR MASS AND SURFACE TROUGH IN PLACE.
DRY FORECAST CONTINUES THROUGH SATURDAY AFTERNOON AS RIDGE
TRANSITIONS EASTWARD...AND SUBSIDENT/DRY AIR MASS LINGERS.
THIS AFTERNOON-TONIGHT...THE COLD FRONT OVER NEBRASKA WILL DROP
SOUTH THIS LATE THIS AFTERNOON AND EVENING WITH SURFACE HIGH
PRESSURE SETTLING IN FROM THE NORTHERN PLAINS. A COOLER/DRIER AIR
MASS WILL ACCOMPANY THIS HIGH PRESSURE SYSTEM...RETURNING
OVERNIGHT LOWS TO SEASONAL VALUES AROUND 20F. NAM/SREF CONTINUE TO
HINT AT SURFACE RH VALUES APPROACHING SATURATION AND POSSIBLE FOG
DEVELOPMENT. SOUNDINGS INDICATE THIS WILL BE VERY SHALLOW MOIST
LAYER...AND A DRY BL WILL GENERALLY INHIBIT FOG/STRATUS
DEVELOPMENT TONIGHT. HRRR/RAP CURRENTLY SHOWING NO FOG DEVELOPMENT
OVER OUR CWA. WHILE WE COULD SEE SOME SHALLOW FOG DEVELOPMENT...AT
THIS POINT CONFIDENCE IS JUST TOO LOW TO ADD.
SATURDAY...SHORTWAVE RIDING WILL TRANSITION THROUGH THE PLAINS ON
SATURDAY...WITH A SHORTWAVE TROUGH MOVING OUT OF THE GREAT BASIN
TOWARDS THE CENTRAL ROCKIES SATURDAY AFTERNOON. SW FLOW ALOFT WILL
DEVELOP BY SATURDAY AFTERNOON BETWEEN THESE FEATURES...WITH
INCREASING MID TO HIGH CLOUD COVER THROUGH THE DAY FROM THE WEST
TO THE EAST. LEE TROUGH AND SOUTHERLY FLOW WILL DEVELOP IN
RESPONSE TO THIS SHIFT IN FLOW ALOFT...SUPPORTING WAA ACROSS OUR
CWA AS THE SURFACE HIGH RETREATS EASTWARD.
NOT A LOT OF CONFIDENCE IN WHICH WILL WIN OUT: WAA WITH SOUTHERLY
FLOW OR LIMITED DIURNAL HEATING DUE TO INCREASING CLOUD COVER. I
ONLY MADE MINOR ADJUSTMENTS TO HIGH TEMP FORECAST...WHICH HAS
HIGHS NEAR 50 IN THE WEST AND THE MID 40S IN THE EAST. I COULD SEE
LOCATIONS IN THE WEST APPROACHING THE MID 50S IF CLOUD COVER HAS
MINIMAL IMPACT AND WE ACHIEVE FULL DAYTIME MIXING.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 222 PM MST FRI DEC 5 2014
AN UPPER TROUGH WILL MOVE INTO THE CENTRAL PLAINS SATURDAY NIGHT
FOLLOWED BY NORTHWEST FLOW SUNDAY. A RIDGE WILL MOVE EAST FROM THE
ROCKIES AND INTO THE PLAINS MONDAY. A SURFACE TROUGH WILL BE OVER
EASTERN COLORADO SATURDAY NIGHT AND THEN SHIFT EAST SUNDAY. SURFACE
HIGH PRESSURE WILL MOVE INTO THE CENTRAL PLAINS SUNDAY AND MONDAY.
THE UPPER TROUGH THAT COMES THROUGH THE FA SATURDAY NIGHT WILL BE
LACKING FOR MOISTURE. MOISTURE IMPROVES SOME AS THE SYSTEM EXITS
THE FAR EASTERN FA SUNDAY MORNING. FORECAST SOUNDINGS ACROSS THE FA
SATURDAY NIGHT SHOW CLOUD BASES FROM 8 TO 11KFT. FORECAST SOUNDINGS
SHOW SATURATION NEAR THE SURFACE EAST OF THE COLORADO LINE FOR
STRATUS/FOG AND LIGHT DRIZZLE WITH SURFACE TEMPERATURES ABOVE
FREEZING. SUBSIDENCE MOVES INTO THE FA LATE SUNDAY MORNING AND
CONTINUES THROUGH MONDAY. CONSEQUENTLY POPS WILL BE NIL FROM
SATURDAY NIGHT THROUGH MONDAY.
MIN TEMPERATURES SATURDAY AND SUNDAY NIGHTS WILL VARY FROM THE UPPER
20S TO AROUND 30. MAX TEMPERATURES SUNDAY SHOULD RANGE FROM 45 TO
50. MAX TEMPERATURES MONDAY SHOULD WARM TO THE MID AND UPPER 50S.
IN THE EXTENDED...(MONDAY NIGHT THROUGH FRIDAY)...A RIDGE WILL
PERSIST OVER THE CENTRAL PLAINS THROUGH THURSDAY AND THEN SHIFT EAST
FRIDAY WITH ZONAL FLOW EAST OF THE ROCKIES. SURFACE HIGH PRESSURE
WILL CONTINUE OVER THE CENTRAL PLAINS THROUGH TUESDAY. A TROUGH
MOVES INTO EASTERN COLORADO THURSDAY AND FRIDAY AS HIGH PRESSURE
DRIFTS EAST.
THE GFS BRINGS A SHORTWAVE THROUGH TUESDAY NIGHT WHILE THE ECMWF
KEEPS IT MUCH FURTHER NORTH. ALSO GFS SOUNDINGS SHOW VERY SHALLOW
MOISTURE WITH THE SYSTEM. FOR NOW WILL KEEP SILENT POPS FOR TUESDAY
NIGHT. AS A RESULT THE ENTIRE EXTENDED FORECAST WILL BE DRY WITH NO
OTHER SIGNIFICANT FORCING FOR THE REMAINING PERIODS.
MAX TEMPERATURES WILL VARY FROM THE MID 50S TO THE MID AND UPPER 50S
THURSDAY AND FRIDAY. MIN TEMPERATURES WILL COOL TO THE UPPER 20S TO
AROUND 30.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1029 AM MST FRI DEC 5 2014
VFR CONDITIONS SHOULD PREVAIL THROUGH THE TAF PERIOD AT BOTH KGLD
AND KMCK. THERE IS STILL A HINT OF POSSIBLE LIGHT FOG REDUCING VIS
TEMPORARILY AT EITHER TERMINAL IN NAM/SREF WITH GOOD RADIATIONAL
CONDITIONS IN PLACE. HOWEVER...WITH DRY LOW LEVEL AIR ADVECTING
SOUTH AND SHORT RANGE AND STATISTICAL GUIDANCE FAVORING VFR
CONFIDENCE IS TOO LOW TO ADD SUB VFR GROUPS TO TAFS. GUSTY WINDS
THIS AFTERNOON WILL DIMINISH AFTER COLD FRONT PUSHES SOUTH AND
HIGH PRESSURE MOVES INTO THE PLAINS THIS EVENING. WINDS WILL
EVENTUALLY SHIFT TO THE SOUTH BY MID TO LATE MORNING SATURDAY WITH
AN INCREASING TREND AS LEE TROUGH DEVELOPS OVER EASTERN COLORADO.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...FS
AVIATION...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1246 PM MST FRI DEC 5 2014
.SHORT TERM...(THIS AFTERNOON THROUGH SATURDAY)
ISSUED AT 1246 PM MST FRI DEC 5 2014
LATEST WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOW RIDGING
BUILDING ACROSS INTER-MOUNTAIN WEST...WITH A SHORTWAVE TROUGH
CENTERED OVER EASTERN KANSAS. SUBSIDENCE/CLEARING IS IN PLACE
OVER OUR CWA. AT THE THE SURFACE...PRE FRONTAL LOW PRESSURE IS IN
PLACE ACROSS KANSAS AND EASTERN COLORADO WITH A WEAK COLD FRONT
OVER SOUTHERN NEBRASKA. AHEAD OF THE COLD FRONT TEMPERATURES HAVE
WARMED TO NEAR 60 DEGREES OVER MUCH OF THE CWA WITH A WELL MIXED
AIR MASS AND SURFACE TROUGH IN PLACE.
DRY FORECAST CONTINUES THROUGH SATURDAY AFTERNOON AS RIDGE
TRANSITIONS EASTWARD...AND SUBSIDENT/DRY AIR MASS LINGERS.
THIS AFTERNOON-TONIGHT...THE COLD FRONT OVER NEBRASKA WILL DROP
SOUTH THIS LATE THIS AFTERNOON AND EVENING WITH SURFACE HIGH
PRESSURE SETTLING IN FROM THE NORTHERN PLAINS. A COOLER/DRIER AIR
MASS WILL ACCOMPANY THIS HIGH PRESSURE SYSTEM...RETURNING
OVERNIGHT LOWS TO SEASONAL VALUES AROUND 20F. NAM/SREF CONTINUE TO
HINT AT SURFACE RH VALUES APPROACHING SATURATION AND POSSIBLE FOG
DEVELOPMENT. SOUNDINGS INDICATE THIS WILL BE VERY SHALLOW MOIST
LAYER...AND A DRY BL WILL GENERALLY INHIBIT FOG/STRATUS
DEVELOPMENT TONIGHT. HRRR/RAP CURRENTLY SHOWING NO FOG DEVELOPMENT
OVER OUR CWA. WHILE WE COULD SEE SOME SHALLOW FOG DEVELOPMENT...AT
THIS POINT CONFIDENCE IS JUST TOO LOW TO ADD.
SATURDAY...SHORTWAVE RIDING WILL TRANSITION THROUGH THE PLAINS ON
SATURDAY...WITH A SHORTWAVE TROUGH MOVING OUT OF THE GREAT BASIN
TOWARDS THE CENTRAL ROCKIES SATURDAY AFTERNOON. SW FLOW ALOFT WILL
DEVELOP BY SATURDAY AFTERNOON BETWEEN THESE FEATURES...WITH
INCREASING MID TO HIGH CLOUD COVER THROUGH THE DAY FROM THE WEST
TO THE EAST. LEE TROUGH AND SOUTHERLY FLOW WILL DEVELOP IN
RESPONSE TO THIS SHIFT IN FLOW ALOFT...SUPPORTING WAA ACROSS OUR
CWA AS THE SURFACE HIGH RETREATS EASTWARD.
NOT A LOT OF CONFIDENCE IN WHICH WILL WIN OUT: WAA WITH SOUTHERLY
FLOW OR LIMITED DIURNAL HEATING DUE TO INCREASING CLOUD COVER. I
ONLY MADE MINOR ADJUSTMENTS TO HIGH TEMP FORECAST...WHICH HAS
HIGHS NEAR 50 IN THE WEST AND THE MID 40S IN THE EAST. I COULD SEE
LOCATIONS IN THE WEST APPROACHING THE MID 50S IF CLOUD COVER HAS
MINIMAL IMPACT AND WE ACHIEVE FULL DAYTIME MIXING.
.LONG TERM...(MONDAY THROUGH THURSDAY)
ISSUED AT 249 AM MST FRI DEC 5 2014
DRY AND WARMER THAN AVERAGE CONDITIONS ARE EXPECTED THROUGH NEXT
WEEK.
A DIRTY SHORT WAVE RIDGE MOVES EAST OF THE ROCKIES AND ACROSS THE
CENTRAL AND NORTHERN HIGH PLAINS REGIONS ON MONDAY AND MONDAY NIGHT.
MODEL SOLUTIONS BEGIN TO DIFFER ON TUESDAY. THE GFS IS MORE
PROGRESSIVE THAN THE ECMWF BRINGING A SHORT WAVE TROUGH THROUGH THE
SOUTHERN AND CENTRAL HIGH PLAINS BY MID DAY TUESDAY WHILE THE ECMWF
IS SLOWER AND SHOWING A DEEPER TROUGH DEVELOPING ALOFT IN THE LEE
OF THE ROCKIES OVER THE SOUTHERN HIGH PLAINS THAT DOES NOT MOVE
THROUGH THE AREA UNTIL TUESDAY NIGHT. BOTH THE ECMWF AND GFS
DEPICT RIDGING FOLLOWING THE UPPER TROUGH...BUT THE ECMWF STILL
LAGS BEHIND THE GFS AS THE RIDGE MOVES EAST OVER THE PLAINS STATES
THURSDAY AND THURSDAY NIGHT. THE SURFACE PATTERN OVER THE CENTRAL
HIGH PLAINS LACKS ANY SIGNIFICANT FEATURES MOVING THROUGH THE
REGION. SURFACE FLOW REMAINS GENERALLY LIGHT AND SOUTHWESTERLY AS
A FRAGMENTED LEE TROUGH REMAINS GENERALLY IN PLACE ALONG THE FRONT
RANGE. SOME ADDITIONAL DEEPENING OF THE SURFACE TROUGH OCCURS NEAR
THE KANSAS AND COLORADO BORDER BY FRIDAY AHEAD OF THE NEXT
SIGNIFICANT UPPER LEVEL TROUGH THAT IS PUSHING INTO THE WESTERN
UNITED STATES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1029 AM MST FRI DEC 5 2014
VFR CONDITIONS SHOULD PREVAIL THROUGH THE TAF PERIOD AT BOTH KGLD
AND KMCK. THERE IS STILL A HINT OF POSSIBLE LIGHT FOG REDUCING VIS
TEMPORARILY AT EITHER TERMINAL IN NAM/SREF WITH GOOD RADIATIONAL
CONDITIONS IN PLACE. HOWEVER...WITH DRY LOW LEVEL AIR ADVECTING
SOUTH AND SHORT RANGE AND STATISTICAL GUIDANCE FAVORING VFR
CONFIDENCE IS TOO LOW TO ADD SUB VFR GROUPS TO TAFS. GUSTY WINDS
THIS AFTERNOON WILL DIMINISH AFTER COLD FRONT PUSHES SOUTH AND
HIGH PRESSURE MOVES INTO THE PLAINS THIS EVENING. WINDS WILL
EVENTUALLY SHIFT TO THE SOUTH BY MID TO LATE MORNING SATURDAY WITH
AN INCREASING TREND AS LEE TROUGH DEVELOPS OVER EASTERN COLORADO.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...LOCKHART
AVIATION...DR
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1131 AM CST FRI DEC 5 2014
...UPDATED AVIATION DISCUSSION...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 201 AM CST FRI DEC 5 2014
WESTERN EDGE OF THE PRECIPITATION EARLIER THIS MORNING APPEARS TO
RELATE WELL WITH THE 700MB MOISTURE ALONG A DEVELOPING 700MB
BAROCLINIC ZONE AND 700-500MB FRONTOGENESIS AHEAD OF AN UPPER
LEVEL TROUGH CROSSING SOUTHWEST KANSAS. BASED ON THIS WILL USE
THESE FEATURES FROM THE LATEST RAP AS A GUIDE AND TAPER THE
PRECIPITATION OFF FROM WEST TO EAST EARLY THIS MORNING. IN
ADDITION TO THE ENDING PRECIPITATION THE RAP AND NAM BOTH
INDICATED DRIER AIR AND SUBSIDENCE WILL DEVELOP EARLY FRIDAY
MORNING BEHIND THE UPPER LEVEL TROUGH SO WILL FAVOR A DECREASING
SKIES QUICKER THAN PREVIOUSLY THOUGHT. GIVEN MORE AFTERNOON SUN
AND 850MB TEMPERATURES AT 00Z SATURDAY WILL CONTINUE TO FAVOR
HIGHS TODAY MAINLY IN THE MID TO UPPER 50S. A FEW LOCATIONS IN
EXTREME SOUTHWEST KANSAS DOES HAVE THE POTENTIAL TO WARM TO AROUND
60S WHILE SLIGHTLY COOLER TEMPERATURES ARE EXPECTED IN CENTRAL
KANSAS GIVEN THE RAINFALL EXPECTED AND CLOUD COVER LINGERING
LONGER.
TONIGHT A SURFACE RIDGE AXIS WILL BUILD INTO WESTERN KANSAS UNDER
MOSTLY CLEAR SKIES. THE LIGHTER WINDS WILL BE OVER NORTH CENTRAL
AND SOUTH CENTRAL KANSAS TOWARDS 12Z SATURDAY SO WILL LEAN TOWARDS
THE COOLER MAV GUIDANCE IN THESE LOCATIONS. ELSEWHERE WILL FOLLOW
THE LATEST GUIDANCE WITH LOWS IN THE MID TO UPPER 20S.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 408 AM CST FRI DEC 5 2014
A LOW AMPLITUDE RIDGE WILL SETTLE IN ALOFT ON SATURDAY AS THE
SURFACE RIDGE SLIDES ACROSS WESTERN AND CENTRAL KANSAS PROVIDING
LIGHT AND VARIABLE WIND. THE MODELS SUGGEST THAT BY LATE IN THE DAY,
THE WIND WILL TURN SOUTHERLY. THIS PATTERN EASILY SUPPORTS THE
SLIGHTLY WARMER BIAS CORRECTED MOS SOLUTIONS IN THE WESTERN COUNTIES
OF TEMPERATURES AROUND OR IN EXCESS OF 50 DEGREES, ESPECIALLY GIVEN
ABUNDANT INSOLATION.
THE SOUTHERLY WINDS AND RESULTANT BOUNDARY LAYER MOISTURE ADVECTION
WILL PROMOTE SLIGHTLY MORE MILD TEMPERATURES ON SATURDAY NIGHT AND
SUNDAY MORNING. MODELS DIFFER SIGNIFICANTLY WITH RESPECT TO SPATIAL
PLACEMENT OF HIGHEST VALUES IN LOW LEVEL RH FIELDS HOWEVER THE
PATTERN WELL SUPPORTS STRATUS DEVELOPMENT IN ADVANCE OF THE NEXT
TROUGH MOVING TOWARD THE REGION FOR SUNDAY AFTERNOON. ADVECTION
FOG WILL BE POSSIBLE AS WELL WHICH THE NAM LOW VISIBILITY
PROBABILITIES ARE ALREADY FAVORING. FOG WAS ADDED TO THE FORECAST
FOR SATURDAY NIGHT AND SUNDAY MORNING, HOWEVER FORECAST SOUNDINGS
ARE NOT QUITE CONVINCING FOR SHOWERS OR DRIZZLE. THE GFS AND ECMWF
INDICATE SMALL QPF ASSOCIATED WITH THE NEST WAVE ACROSS THE DEEP
SOUTHERN HIGH PLAINS ON SUNDAY. THESE LOWER RESOLUTION MODELS
COULD BE OVERDOING PRECIPITATION AT THIS TIMESCALE BUT THE
EVOLUTION OF THE PATTERN WILL BE SOMETHING TO WATCH GOING FOREWORD
IF IT IS ABLE TO BE MORE DIRECTLY FOCUSED ON SW KS.
A BUMP TO SLIGHTLY HIGHER THAN NORMAL DAILY HIGH TEMPERATURES IS
FORECAST TO FOLLOW FOR SUNDAY AND BEYOND AS A BROAD GENERAL MEAN
RIDGE PATTERN DEVELOPS AND INFLUENCES THE REGION THROUGH THE NEXT
WEEKEND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1131 AM CST FRI DEC 5 2014
HIGH PRESSURE BUILDING INTO THE CENTRAL HIGH PLAINS WILL BRING VFR
CONDITIONS TO THE CENTRAL AND SOUTHWEST KANSAS TAF SITES THROUGH
THIS PERIOD. WINDS WILL GENERALLY BE FROM THE NORTH AT AROUND 10
KNOTS OR SO.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 57 26 46 36 / 90 0 0 10
GCK 58 25 46 37 / 10 0 0 10
EHA 60 30 53 40 / 0 0 0 10
LBL 59 27 50 39 / 70 0 0 10
HYS 56 22 44 33 / 30 0 0 10
P28 56 30 44 37 / 100 0 0 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BURGERT
LONG TERM...RUSSELL
AVIATION...GERARD
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
643 AM CST FRI DEC 5 2014
...UPDATED AVIATION...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 201 AM CST FRI DEC 5 2014
WESTERN EDGE OF THE PRECIPITATION EARLIER THIS MORNING APPEARS TO
RELATE WELL WITH THE 700MB MOISTURE ALONG A DEVELOPING 700MB
BAROCLINIC ZONE AND 700-500MB FRONTOGENESIS AHEAD OF AN UPPER
LEVEL TROUGH CROSSING SOUTHWEST KANSAS. BASED ON THIS WILL USE
THESE FEATURES FROM THE LATEST RAP AS A GUIDE AND TAPER THE
PRECIPITATION OFF FROM WEST TO EAST EARLY THIS MORNING. IN
ADDITION TO THE ENDING PRECIPITATION THE RAP AND NAM BOTH
INDICATED DRIER AIR AND SUBSIDENCE WILL DEVELOP EARLY FRIDAY
MORNING BEHIND THE UPPER LEVEL TROUGH SO WILL FAVOR A DECREASING
SKIES QUICKER THAN PREVIOUSLY THOUGHT. GIVEN MORE AFTERNOON SUN
AND 850MB TEMPERATURES AT 00Z SATURDAY WILL CONTINUE TO FAVOR
HIGHS TODAY MAINLY IN THE MID TO UPPER 50S. A FEW LOCATIONS IN
EXTREME SOUTHWEST KANSAS DOES HAVE THE POTENTIAL TO WARM TO AROUND
60S WHILE SLIGHTLY COOLER TEMPERATURES ARE EXPECTED IN CENTRAL
KANSAS GIVEN THE RAINFALL EXPECTED AND CLOUD COVER LINGERING
LONGER.
TONIGHT A SURFACE RIDGE AXIS WILL BUILD INTO WESTERN KANSAS UNDER
MOSTLY CLEAR SKIES. THE LIGHTER WINDS WILL BE OVER NORTH CENTRAL
AND SOUTH CENTRAL KANSAS TOWARDS 12Z SATURDAY SO WILL LEAN TOWARDS
THE COOLER MAV GUIDANCE IN THESE LOCATIONS. ELSEWHERE WILL FOLLOW
THE LATEST GUIDANCE WITH LOWS IN THE MID TO UPPER 20S.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 408 AM CST FRI DEC 5 2014
A LOW AMPLITUDE RIDGE WILL SETTLE IN ALOFT ON SATURDAY AS THE
SURFACE RIDGE SLIDES ACROSS WESTERN AND CENTRAL KANSAS PROVIDING
LIGHT AND VARIABLE WIND. THE MODELS SUGGEST THAT BY LATE IN THE DAY,
THE WIND WILL TURN SOUTHERLY. THIS PATTERN EASILY SUPPORTS THE
SLIGHTLY WARMER BIAS CORRECTED MOS SOLUTIONS IN THE WESTERN COUNTIES
OF TEMPERATURES AROUND OR IN EXCESS OF 50 DEGREES, ESPECIALLY GIVEN
ABUNDANT INSOLATION.
THE SOUTHERLY WINDS AND RESULTANT BOUNDARY LAYER MOISTURE ADVECTION
WILL PROMOTE SLIGHTLY MORE MILD TEMPERATURES ON SATURDAY NIGHT AND
SUNDAY MORNING. MODELS DIFFER SIGNIFICANTLY WITH RESPECT TO SPATIAL
PLACEMENT OF HIGHEST VALUES IN LOW LEVEL RH FIELDS HOWEVER THE
PATTERN WELL SUPPORTS STRATUS DEVELOPMENT IN THE TIMEFRAME IN
ADVANCE OF THE NEXT TROUGH MOVING TOWARD THE REGION FOR SUNDAY
AFTERNOON. ADVECTION FOG WILL BE POSSIBLE AS WELL WHICH THE NAM
LOW VISIBILITY PROBABILITIES ARE ALREADY FAVORING. FOG WAS ADDED
TO THE FORECAST FOR SATURDAY NIGHT ANS SUNDAY MORING, HOWEEVER
FORECAST SOUNDINGS ARE NOT QUITE CONVINCING FOR SHOWERS OR DRIZZLE.
THE GFS AND ECMWF INDICATE SMALL QPF ASSOCIATED WITH THE NEST
WAVE ACROSS THE DEEP SOUTHERN HIGH PLAINS ON SUNDAY. THESE LOWER
RESOLUTON MODELS COULD BE OVERDOING PRECIPITATION AT THIS
TIMESCALE BUT THE EVOLUTION OF THE PATTERN WILL BE SOMETHING TO
WATCH GOING FOREWORD IF IT IS ABLE TO BE MORE DIRECTLY FOCUSED ON
SW KS.
A BUMP TO SLIGHTLY HIGHER THAN NORMAL DAILY HIGH TEMPERATURES IS
FORECAST TO FOLLOW FOR SUNDAY AND BEYOND AS A BROAD GENERAL MEAN
RIDGE PATTERN DEVELOPS AND INFLUENCES THE REGION THROUGH THE NEXT
WEEKEND.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 641 AM CST FRI DEC 5 2014
AN AREA OF DEEP MOIST ISENTROPIC LIFT ACROSS SOUTH CENTRAL KS THIS
MORNING WAS PRODUCING A BAND OF RAIN FROM NEAR LIBERAL THROUGH
CENTRAL AND EASTERN KS. PREVAILING CIELINGS WERE GENERALLY ABOVE THE
IFR CATEGORY HOWEVER LOCALLY 3 SM VISIBILITIES WILL BE PERIODIC
THROUGH THE MORNING. A COLD FRONT WILL MOVE THROUGH THE AREA IN THE
AFTERNOON BRINGING DRIER AIR ACROSS THE AREA.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 57 26 46 36 / 40 0 0 10
GCK 58 25 46 37 / 10 0 0 10
EHA 60 30 53 40 / 0 0 0 10
LBL 59 27 50 39 / 10 0 0 10
HYS 54 22 44 33 / 20 0 0 10
P28 56 30 44 37 / 90 0 0 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BURGERT
LONG TERM...RUSSELL
AVIATION...RUSSELL
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
423 AM CST FRI DEC 5 2014
...UPDATED LONG TERM SECTION...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 201 AM CST FRI DEC 5 2014
WESTERN EDGE OF THE PRECIPITATION EARLIER THIS MORNING APPEARS TO
RELATE WELL WITH THE 700MB MOISTURE ALONG A DEVELOPING 700MB
BAROCLINIC ZONE AND 700-500MB FRONTOGENESIS AHEAD OF AN UPPER
LEVEL TROUGH CROSSING SOUTHWEST KANSAS. BASED ON THIS WILL USE
THESE FEATURES FROM THE LATEST RAP AS A GUIDE AND TAPER THE
PRECIPITATION OFF FROM WEST TO EAST EARLY THIS MORNING. IN
ADDITION TO THE ENDING PRECIPITATION THE RAP AND NAM BOTH
INDICATED DRIER AIR AND SUBSIDENCE WILL DEVELOP EARLY FRIDAY
MORNING BEHIND THE UPPER LEVEL TROUGH SO WILL FAVOR A DECREASING
SKIES QUICKER THAN PREVIOUSLY THOUGHT. GIVEN MORE AFTERNOON SUN
AND 850MB TEMPERATURES AT 00Z SATURDAY WILL CONTINUE TO FAVOR
HIGHS TODAY MAINLY IN THE MID TO UPPER 50S. A FEW LOCATIONS IN
EXTREME SOUTHWEST KANSAS DOES HAVE THE POTENTIAL TO WARM TO AROUND
60S WHILE SLIGHTLY COOLER TEMPERATURES ARE EXPECTED IN CENTRAL
KANSAS GIVEN THE RAINFALL EXPECTED AND CLOUD COVER LINGERING
LONGER.
TONIGHT A SURFACE RIDGE AXIS WILL BUILD INTO WESTERN KANSAS UNDER
MOSTLY CLEAR SKIES. THE LIGHTER WINDS WILL BE OVER NORTH CENTRAL
AND SOUTH CENTRAL KANSAS TOWARDS 12Z SATURDAY SO WILL LEAN TOWARDS
THE COOLER MAV GUIDANCE IN THESE LOCATIONS. ELSEWHERE WILL FOLLOW
THE LATEST GUIDANCE WITH LOWS IN THE MID TO UPPER 20S.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 408 AM CST FRI DEC 5 2014
A LOW AMPLITUDE RIDGE WILL SETTLE IN ALOFT ON SATURDAY AS THE
SURFACE RIDGE SLIDES ACROSS WESTERN AND CENTRAL KANSAS PROVIDING
LIGHT AND VARIABLE WIND. THE MODELS SUGGEST THAT BY LATE IN THE DAY,
THE WIND WILL TURN SOUTHERLY. THIS PATTERN EASILY SUPPORTS THE
SLIGHTLY WARMER BIAS CORRECTED MOS SOLUTIONS IN THE WESTERN COUNTIES
OF TEMPERATURES AROUND OR IN EXCESS OF 50 DEGREES, ESPECIALLY GIVEN
ABUNDANT INSOLATION.
THE SOUTHERLY WINDS AND RESULTANT BOUNDARY LAYER MOISTURE ADVECTION
WILL PROMOTE SLIGHTLY MORE MILD TEMPERATURES ON SATURDAY NIGHT AND
SUNDAY MORNING. MODELS DIFFER SIGNIFICANTLY WITH RESPECT TO SPATIAL
PLACEMENT OF HIGHEST VALUES IN LOW LEVEL RH FIELDS HOWEVER THE
PATTERN WELL SUPPORTS STRATUS DEVELOPMENT IN THE TIMEFRAME IN
ADVANCE OF THE NEXT TROUGH MOVING TOWARD THE REGION FOR SUNDAY
AFTERNOON. ADVECTION FOG WILL BE POSSIBLE AS WELL WHICH THE NAM
LOW VISIBILITY PROBABILITIES ARE ALREADY FAVORING. FOG WAS ADDED
TO THE FORECAST FOR SATURDAY NIGHT ANS SUNDAY MORING, HOWEEVER
FORECAST SOUNDINGS ARE NOT QUITE CONVINCING FOR SHOWERS OR DRIZZLE.
THE GFS AND ECMWF INDICATE SMALL QPF ASSOCIATED WITH THE NEST
WAVE ACROSS THE DEEP SOUTHERN HIGH PLAINS ON SUNDAY. THESE LOWER
RESOLUTON MODELS COULD BE OVERDOING PRECIPITATION AT THIS
TIMESCALE BUT THE EVOLUTION OF THE PATTERN WILL BE SOMETHING TO
WATCH GOING FOREWORD IF IT IS ABLE TO BE MORE DIRECTLY FOCUSED ON
SW KS.
A BUMP TO SLIGHTLY HIGHER THAN NORMAL DAILY HIGH TEMPERATURES IS
FORECAST TO FOLLOW FOR SUNDAY AND BEYOND AS A BROAD GENERAL MEAN
RIDGE PATTERN DEVELOPS AND INFLUENCES THE REGION THROUGH THE NEXT
WEEKEND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1124 PM CST THU DEC 4 2014
LIGHT RAIN, MVFR FOG AND LIFR CEILINGS CAN BE EXPECTED EARLY THIS
MORNING AS AN UPPER LEVEL TROUGH MOVES ACROSS THE WESTERN KANSAS.
AS OF 04Z THE WESTERN EDGE OF THE RAIN APPEARS TO RELATE WELL WITH
700MB MOISTURE AND 700-500MB FRONTOGENESIS LOCATED AHEAD OF THIS
UPPER LEVEL TROUGH. USING THE RAP AS GUIDE THE RAIN WILL TAPER OFF
BETWEEN 08Z AND 10Z AT GCK AND HYS AND THEN DDC AROUND 12Z FRIDAY.
AS THE RAIN TAPERS OFF THE CEILINGS AND FOG WILL SLOWLY IMPROVE AS
SOUTHERLY WINDS AT 10 KNOTS OR LESS WILL SHIFT TO THE NORTHWEST.
THE WIND SHIFT WILL BE DUE TO A TROUGH OF LOW PRESSURE WILL MOVE
ACROSS SOUTHWEST KANSAS. THESE NORTHWEST WINDS WILL THEN CONTINUE
AT AROUND 10 KNOTS THROUGH THE REMAINDER OF THE DAY. SUBSIDENCE
AND DRIER AIR RETURNING TO WESTERN KANSAS BEHIND THE UPPER LEVEL
TROUGH WILL RESULT IN VRF CONDITIONS DEVELOPING MID TO LATE
MORNING.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 57 26 46 36 / 40 0 0 10
GCK 58 25 46 37 / 10 0 0 10
EHA 60 30 53 40 / 0 0 0 10
LBL 59 27 50 39 / 10 0 0 10
HYS 54 22 44 33 / 20 0 0 10
P28 56 30 44 37 / 90 0 0 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BURGERT
LONG TERM...RUSSELL
AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
204 AM CST FRI DEC 5 2014
...UPDATED SHORT TERM DISCUSSION...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 201 AM CST FRI DEC 5 2014
WESTERN EDGE OF THE PRECIPITATION EARLIER THIS MORNING APPEARS TO
RELATE WELL WITH THE 700MB MOISTURE ALONG A DEVELOPING 700MB
BAROCLINIC ZONE AND 700-500MB FRONTOGENESIS AHEAD OF AN UPPER
LEVEL TROUGH CROSSING SOUTHWEST KANSAS. BASED ON THIS WILL USE
THESE FEATURES FROM THE LATEST RAP AS A GUIDE AND TAPER THE
PRECIPITATION OFF FROM WEST TO EAST EARLY THIS MORNING. IN
ADDITION TO THE ENDING PRECIPITATION THE RAP AND NAM BOTH
INDICATED DRIER AIR AND SUBSIDENCE WILL DEVELOP EARLY FRIDAY
MORNING BEHIND THE UPPER LEVEL TROUGH SO WILL FAVOR A DECREASING
SKIES QUICKER THAN PREVIOUSLY THOUGHT. GIVEN MORE AFTERNOON SUN
AND 850MB TEMPERATURES AT 00Z SATURDAY WILL CONTINUE TO FAVOR
HIGHS TODAY MAINLY IN THE MID TO UPPER 50S. A FEW LOCATIONS IN
EXTREME SOUTHWEST KANSAS DOES HAVE THE POTENTIAL TO WARM TO AROUND
60S WHILE SLIGHTLY COOLER TEMPERATURES ARE EXPECTED IN CENTRAL
KANSAS GIVEN THE RAINFALL EXPECTED AND CLOUD COVER LINGERING
LONGER.
TONIGHT A SURFACE RIDGE AXIS WILL BUILD INTO WESTERN KANSAS UNDER
MOSTLY CLEAR SKIES. THE LIGHTER WINDS WILL BE OVER NORTH CENTRAL
AND SOUTH CENTRAL KANSAS TOWARDS 12Z SATURDAY SO WILL LEAN TOWARDS
THE COOLER MAV GUIDANCE IN THESE LOCATIONS. ELSEWHERE WILL FOLLOW
THE LATEST GUIDANCE WITH LOWS IN THE MID TO UPPER 20S.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 311 PM CST THU DEC 4 2014
AFTER THE SHORTWAVE TROUGH MENTIONED IN THE SHORT TERM DISCUSSION
PASSES OFF TO THE EAST, SKIES WILL PARTIALLY CLEAR FRIDAY NIGHT
AND SATURDAY AS SURFACE HIGH PRESSURE BUILDS IN. LOWS SHOULD BE IN
THE UPPER 20S TO LOWER 30S WITH HIGHS IN THE MID TO UPPER 40S.
THE NEXT SHORTWAVE TROUGH WILL TRAVERSE THE PLAINS BY SUNDAY; BUT
THERE ARE ONLY SLIGHT RAIN CHANCES IN CENTRAL KANSAS GIVEN A LACK
OF LOW TO MID LEVEL MOISTURE AND ONLY WEAK LIFT. HIGHS SHOULD
REACH INTO THE MID TO HIGH 50S. OTHER WEAK SHORTWAVE TROUGHS WILL
TRAVERSE THE CENTRAL AND NORTHERN PLAINS FROM TUESDAY INTO
WEDNESDAY NIGHT; BUT GIVEN THE CONTINUED LACK OF RICH MOISTURE
AND ONLY WEAK LIFT, PRECIPITATION IS NOT LIKELY. WITH WEAK LEE
TROUGHING, TEMPERATURES WILL BE ABOVE CLIMATOLOGICAL AVERAGES,
WITH LOWS IN THE LOWER TO MID 30S AND HIGHS IN THE UPPER 50S TO
LOWER 60S.
A DEEP UPPER LEVEL TROUGH IS PROGGED BY NEXT FRIDAY AND SATURDAY
OVER THE DESERT SOUTHWEST. AHEAD OF THIS SYSTEM, UPPER LEVEL
TROUGHING WILL DEVELOP OVER THE PLAINS, ALONG WITH HIGH PLAINS
SURFACE TROUGHING. THIS WILL RESULT IN WARMER TEMPERATURES, WITH
HIGHS IN THE UPPER 50S TO LOWER 60S THURSDAY AND FRIDAY. RAIN
CHANCES BY LATE NEXT WEEKEND AND INTO THE 15TH AND 16TH OF
DECEMBER WILL DEPEND ON HOW SLOW THE UPPER LEVEL SYSTEM OVER THE
SOUTHWEST PROGRESSES EASTWARD AND THE RESULTANT MOISTURE SUPPLY
FROM THE SOUTH. IT APPEARS THAT COLD AIR WILL BE LACKING SO THAT
ANY PRECIPITATION THAT DOES FALL SHOULD BE RAIN.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1124 PM CST THU DEC 4 2014
LIGHT RAIN, MVFR FOG AND LIFR CEILINGS CAN BE EXPECTED EARLY THIS
MORNING AS AN UPPER LEVEL TROUGH MOVES ACROSS THE WESTERN KANSAS.
AS OF 04Z THE WESTERN EDGE OF THE RAIN APPEARS TO RELATE WELL WITH
700MB MOISTURE AND 700-500MB FRONTOGENESIS LOCATED AHEAD OF THIS
UPPER LEVEL TROUGH. USING THE RAP AS GUIDE THE RAIN WILL TAPER OFF
BETWEEN 08Z AND 10Z AT GCK AND HYS AND THEN DDC AROUND 12Z FRIDAY.
AS THE RAIN TAPERS OFF THE CEILINGS AND FOG WILL SLOWLY IMPROVE AS
SOUTHERLY WINDS AT 10 KNOTS OR LESS WILL SHIFT TO THE NORTHWEST.
THE WIND SHIFT WILL BE DUE TO A TROUGH OF LOW PRESSURE WILL MOVE
ACROSS SOUTHWEST KANSAS. THESE NORTHWEST WINDS WILL THEN CONTINUE
AT AROUND 10 KNOTS THROUGH THE REMAINDER OF THE DAY. SUBSIDENCE
AND DRIER AIR RETURNING TO WESTERN KANSAS BEHIND THE UPPER LEVEL
TROUGH WILL RESULT IN VRF CONDITIONS DEVELOPING MID TO LATE
MORNING.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 57 26 47 32 / 50 0 0 10
GCK 58 25 47 30 / 10 0 0 10
EHA 60 30 50 34 / 0 0 0 10
LBL 59 27 48 33 / 10 0 0 10
HYS 54 22 45 31 / 20 0 0 10
P28 56 30 48 34 / 100 0 0 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BURGERT
LONG TERM...FINCH
AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1029 PM MST THU DEC 4 2014
.UPDATE...
ISSUED AT 822 PM MST THU DEC 4 2014
LATEST RADAR AND SURFACE OBSERVATIONS SHOW THAT THE MAIN RAIN
SHIELD IS FURTHER SOUTH THAN PREVIOUSLY EXPECTED. THIS IS CAPTURED
BY THE LATEST NAM...HRRR...AND RAP WHICH GRAZES THE THE FAR SOUTH
AND SOUTHEAST PORTION OF OUR AREA. SO REDUCED OR REMOVED POPS IN
THE CENTRAL PORTION OF THE FORECAST AREA WHILE STILL KEEPING HIGH
POPS IN THE FAR SOUTH AND SOUTHEAST. ALSO MADE MINOR ADJUSTMENTS
TO THE OVERNIGHT MINS AS WELL.
UPDATE ISSUED AT 426 PM MST THU DEC 4 2014
HAVE CLOUDY SKIES ALREADY AND IT IS NOT GOING TO START CLEARING
UNTIL LATER TONIGHT. SO AM GOING TO DRAMATICALLY INCREASE SKY
COVER UNTIL LATER TONIGHT.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 201 PM MST THU DEC 4 2014
A SHORTWAVE TROUGH WILL MOVE THROUGH WESTERLY FLOW ACROSS THE
CENTRAL PLAINS TONIGHT AND FRIDAY. UPPER LEVEL RIDGING WILL OCCUR
OVER THE ROCKIES ON FRIDAY BEHIND THE EXITING TROUGH. A SURFACE
TROUGH OVER EASTERN COLORADO WILL SHIFT EAST INTO KANSAS TONIGHT
FOLLOWED BY HIGH PRESSURE FRIDAY.
FORECAST SOUNDINGS ARE TOO DRY FOR MEASURABLE PRECIPITATION UNTIL
SOMETIME AROUND 06Z FRIDAY IN THE SOUTHERN FA. TEMPERATURE PROFILES
INDICATE PRECIPITATION SHOULD BE ALL RAIN. SOUNDINGS DRY OUT BY 12Z
SO THE WINDOW FOR PRECIPITATION WILL BE BRIEF. SOME LOW LEVEL
SATURATION WITH A DRY LAYER ABOVE INDICATES THAT STRATUS AND PATCHY
FOG MAY LINGER THROUGH 15Z AS THE SYSTEM EXITS THE FA. PLAN TO GO
WITH LIKELY POPS IN THE FAR SOUTHERN FA WITH A FAIRLY TIGHT GRADIENT
OF CHANCE AND SLIGHT CHANCE POPS ACROSS THE SOUTHEAST HALF OF THE
FA. DRY CONDITIONS WILL RESUME FOR THE REST OF FRIDAY WITH NIL POPS.
MIN TEMPERATURES TONIGHT SHOULD COOL TO THE LOWER 30S WITH CLOUDY
SKIES. MAX TEMPERATURES FRIDAY SHOULD RISE TO THE MID 50S UNDER
MOSTLY SUNNY SKIES.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 201 PM MST THU DEC 4 2014
FRIDAY NIGHT-SATURDAY...WEAK COLD FRONT DROPS SOUTH OVER THE CWA
WITH SURFACE HIGH PRESSURE SETTLING IN FROM THE NORTH. DECREASING
WINDS/CLEARING SKIES WILL SUPPORT GOOD RADIATIONAL CONDITIONS.
HOWEVER LOWER SURFACE-BL TD VALUES ADVECTING IN FROM THE NORTH MAY
LIMIT POTENTIAL FOR FOG DEVELOPMENT. NAM/SREF CONTINUE TO SHOW
POTENTIAL FOR LOW VIS DESPITE MARGINAL BL MOISTURE IN PLACE. DUE
TO THE GOOD RADIATIONAL CONDITIONS I COULDNT RULE OUT PATCHY
FOG...BUT CONFIDENCE ISNT HIGH. COOLER AIR MASS ALOFT AND
INCREASING CLOUD COVER WILL RESULT IN TEMPS CLOSER TO SEASONAL
NORMALS SATURDAY (MID 40S). THERE COULD BE BETTER TEMP RECOVERY IN
THE WEST DEPENDING ON BREAKS IN CLOUD COVER DURING THE DAY...SO WE
COULD SEE HIGHS IN THE LOWER 50S. CONFIDENCE IS NOT HIGH ON TEMPS
DUE TO POTENTIAL IMPACTS FROM CLOUD COVER.
SUNDAY-THURSDAY...QUASI-ZONAL FLOW WILL PERSIST ACROSS THE US WITH
SERIES OF SHORTWAVE TROUGHS/RIDGES PROGRESSING ACROSS THE NORTHERN
PLAINS THROUGH THE EXTENDED PERIODS. DESPITE SUBTLE DIFFERENCES IN
PROGRESSIVE WAVES WITHIN THE MEAN FLOW...DETERMINISTIC GUIDANCE IS
CURRENTLY FAVORING DRY CONDITIONS OVER OUR CWA THROUGH THE EXTENDED
PERIODS.
STRONGEST SHORTWAVE TROUGH IS PROGGED TO MOVE ACROSS THE CENTRAL
ROCKIES/NORTHERN PLAINS SATURDAY NIGHT THROUGH SUNDAY. WHILE GOOD
FORCING WILL BE IN PLACE MOISTURE RETURN IS LIMITED TO THE EAST DUE
TO THE FAST NATURE OF THIS SYSTEM AND QUICK TRANSITION TO W/NW FLOW
ALOFT AS SHORTWAVE RIDGING QUICKLY BUILDS INTO THE CENTRAL ROCKIES.
12Z DETERMINISTIC GUIDANCE HAS TRENDED EAST WITH LIGHT PRECIP
SIGNAL COMPARED TO 00Z/06Z GUIDANCE. GEFS MEAN IS STILL SHOWING
LIMITED 0.01 POTENTIAL IN OUR EASTERN CWA...HOWEVER MAJORITY OF
ENSEMBLE CLUSTER IS EAST OF THIS. I COULDNT RULE OUT A SPRINKLE OR
FLURRY IN OUR EASTERN CWA SATURDAY NIGHT/SUNDAY MORNING...HOWEVER AT
THIS POINT DRY SEEMS TO BE THE WAY TO GO.
ABOVE NORMAL HIGH TEMPERATURES WILL BE FAVORED SUNDAY-THURSDAY WITH
RISING HEIGHTS ALOFT AND SOUTHERLY LOW LEVEL FLOW FAVORED OVER THE
WESTERN PLAINS. COLLABORATIVE BLEND FOR OUR CWA RESULTS IN HIGHS
EARLY NEXT WEEK IN THE MID 50S...TO AROUND 60 BY THE MIDDLE OF NEXT
WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1026 PM MST THU DEC 4 2014
VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD. WINDS WILL BE
LIGHT AND SHIFTING UNTIL LATE IN THE MORNING WHEN A COLD FRONT
MOVES THROUGH. AT THAT TIME...NORTH WINDS WILL BECOME
GUSTY...ESPECIALLY AT KGLD. THE WINDS STOP BECOMING GUSTY LATE IN
THE AFTERNOON.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...BULLER
SHORT TERM...FS
LONG TERM...DR
AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1126 PM CST THU DEC 4 2014
...UPDATED SYNOPSIS AND AVIATION DISCUSSION...
.SYNOPSIS...
ISSUED AT 1124 PM CST THU DEC 4 2014
AT 00Z FRIDAY A 500MB TROUGH WAS LOCATED OVER NEW MEXICO AND WAS
ALSO ASSOCIATED WITH THE LEFT EXIT REGION OF A 250 MB JET STREAK
WHICH EXTENDED FROM BAJA MEXICO INTO THE THE PANHANDLE OF TEXAS.
AHEAD OF THE 500MB TROUGH AN AREA OF HIGHER RELATIVE HUMIDITIES
WERE OBSERVED ALONG A WEAK 700MB BAROCLINIC ZONE WHICH EXTENDED
FROM NORTHEAST NEW MEXICO TO NORTHEAST KANSAS. 850MB WARM AIR
ADVECTION AND MOISTURE ADVECTION WAS OBSERVED NORTH OF A SURFACE
WARM FRONT THAT STRETCHED FROM NORTHEAST NEW MEXICO, ACROSS THE
TEXAS PANHANDLE INTO SOUTHWEST OKLAHOMA. FURTHER NORTH A SURFACE
COLD FRONT EXTENDED FROM MINNESOTA ACROSS SOUTH DAKOTA INTO
NORTHEAST WYOMING.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 310 PM CST THU DEC 4 2014
THE 12Z NAM MODEL MOVES THE SHORTWAVE TROUGH OUT OVER THE CENTRAL
HIGH PLAINS TONIGHT AND INTO CENTRAL AND EASTERN KANSAS BY FRIDAY
AFTERNOON. SOUTHERLY FLOW ACROSS THE CENTRAL AND SOUTHERN PLAINS WAS
PUSHING MOIST AIR TOWARD SOUTHWEST KANSAS. MODEL ISENTROPIC FIELDS
INDICATE THE GREATEST ASCENT EXTENDING FROM FAR SOUTHWEST KANSAS
INTO CENTRAL AND SOUTH CENTRAL KANSAS THIS EVENING. THIS WILL BE THE
FOCUS FOR THE BEST RAINFALL OVERNIGHT AS THE LOW LEVEL MOISTURE
CONTINUES TO STREAM INTO THE AREA FROM THE SOUTHERN PLAINS. UPWARDS
OF A HALF TO ONE INCH OF RAIN COULD FALL IN THIS AREA. WHILE MOST
LOCATIONS WILL SEE SOME MEASURABLE PRECIPITATION, THE AREA FROM
SYRACUSE THROUGH SCOTT CITY AND WAKEENEY WILL SEE AMOUNTS GENERALLY
LESS THAN A QUARTER INCH.
AS THE UPPER WAVE MOVES OUT, THE RAIN WILL BE WINDING DOWN FROM WEST
TO EAST THROUGH THE EARLY MORNING HOURS. LIGHT SOUTHERLY WINDS WILL
BECOME LIGHT FROM THE NORTH AS THE THE RAIN MOVES OUT. FAIRLY
SATURATED BOUNDARY LAYER CONDITIONS ARE EXPECTED TO RESULT IN AREAS
OF FOG DEVELOPING ESPECIALLY AFTER THE RAIN ENDS. WILL CONTINUE THE
TREND FROM THE PREVIOUS SHIFT OF MENTIONING AREAS OF FOG TONIGHT
WITH VISIBILITIES DOWN TO A MILE IN SOME LOCATIONS. NORTHERLY WINDS
WILL INCREASE LATE TONIGHT WHICH WILL HELP INCREASE LOW LEVEL MIXING
LATE TONIGHT AND EARLY FRIDAY.
RAIN SHOULD BE ENDING OVER CENTRAL AND SOUTH CENTRAL KANSAS BY MID
TO LATE MORNING ON FRIDAY. CLOUDS WILL BE DIMINISHING FROM WEST TO
EAST AS THE WAVE MOVES EAST AND UPPER RIDGING AND DRIER AIR MOVES
IN. HIGH TEMPERATURES SHOULD BE IN THE 50S IN MOST AREAS WITH HIGHS
NEAR 60 POSSIBLE ALONG THE COLORADO BORDER.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 311 PM CST THU DEC 4 2014
AFTER THE SHORTWAVE TROUGH MENTIONED IN THE SHORT TERM DISCUSSION
PASSES OFF TO THE EAST, SKIES WILL PARTIALLY CLEAR FRIDAY NIGHT
AND SATURDAY AS SURFACE HIGH PRESSURE BUILDS IN. LOWS SHOULD BE IN
THE UPPER 20S TO LOWER 30S WITH HIGHS IN THE MID TO UPPER 40S.
THE NEXT SHORTWAVE TROUGH WILL TRAVERSE THE PLAINS BY SUNDAY; BUT
THERE ARE ONLY SLIGHT RAIN CHANCES IN CENTRAL KANSAS GIVEN A LACK
OF LOW TO MID LEVEL MOISTURE AND ONLY WEAK LIFT. HIGHS SHOULD
REACH INTO THE MID TO HIGH 50S. OTHER WEAK SHORTWAVE TROUGHS WILL
TRAVERSE THE CENTRAL AND NORTHERN PLAINS FROM TUESDAY INTO
WEDNESDAY NIGHT; BUT GIVEN THE CONTINUED LACK OF RICH MOISTURE
AND ONLY WEAK LIFT, PRECIPITATION IS NOT LIKELY. WITH WEAK LEE
TROUGHING, TEMPERATURES WILL BE ABOVE CLIMATOLOGICAL AVERAGES,
WITH LOWS IN THE LOWER TO MID 30S AND HIGHS IN THE UPPER 50S TO
LOWER 60S.
A DEEP UPPER LEVEL TROUGH IS PROGGED BY NEXT FRIDAY AND SATURDAY
OVER THE DESERT SOUTHWEST. AHEAD OF THIS SYSTEM, UPPER LEVEL
TROUGHING WILL DEVELOP OVER THE PLAINS, ALONG WITH HIGH PLAINS
SURFACE TROUGHING. THIS WILL RESULT IN WARMER TEMPERATURES, WITH
HIGHS IN THE UPPER 50S TO LOWER 60S THURSDAY AND FRIDAY. RAIN
CHANCES BY LATE NEXT WEEKEND AND INTO THE 15TH AND 16TH OF
DECEMBER WILL DEPEND ON HOW SLOW THE UPPER LEVEL SYSTEM OVER THE
SOUTHWEST PROGRESSES EASTWARD AND THE RESULTANT MOISTURE SUPPLY
FROM THE SOUTH. IT APPEARS THAT COLD AIR WILL BE LACKING SO THAT
ANY PRECIPITATION THAT DOES FALL SHOULD BE RAIN.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1124 PM CST THU DEC 4 2014
LIGHT RAIN, MVFR FOG AND LIFR CEILINGS CAN BE EXPECTED EARLY THIS
MORNING AS AN UPPER LEVEL TROUGH MOVES ACROSS THE WESTERN KANSAS.
AS OF 04Z THE WESTERN EDGE OF THE RAIN APPEARS TO RELATE WELL WITH
700MB MOISTURE AND 700-500MB FRONTOGENESIS LOCATED AHEAD OF THIS
UPPER LEVEL TROUGH. USING THE RAP AS GUIDE THE RAIN WILL TAPER OFF
BETWEEN 08Z AND 10Z AT GCK AND HYS AND THEN DDC AROUND 12Z FRIDAY.
AS THE RAIN TAPERS OFF THE CEILINGS AND FOG WILL SLOWLY IMPROVE AS
SOUTHERLY WINDS AT 10 KNOTS OR LESS WILL SHIFT TO THE NORTHWEST.
THE WIND SHIFT WILL BE DUE TO A TROUGH OF LOW PRESSURE WILL MOVE
ACROSS SOUTHWEST KANSAS. THESE NORTHWEST WINDS WILL THEN CONTINUE
AT AROUND 10 KNOTS THROUGH THE REMAINDER OF THE DAY. SUBSIDENCE
AND DRIER AIR RETURNING TO WESTERN KANSAS BEHIND THE UPPER LEVEL
TROUGH WILL RESULT IN VRF CONDITIONS DEVELOPING MID TO LATE
MORNING.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 40 55 28 47 / 100 20 0 0
GCK 37 57 27 47 / 90 10 0 0
EHA 38 58 30 50 / 100 0 0 0
LBL 39 58 29 48 / 100 10 0 0
HYS 38 54 26 45 / 90 10 0 0
P28 42 54 32 48 / 100 70 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...BURGERT
SHORT TERM...GERARD
LONG TERM...FINCH
AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS JACKSON KY
137 AM EST FRI DEC 5 2014
.UPDATE...
ISSUED AT 137 AM EST FRI DEC 5 2014
BLENDED LATEST TEMP/DEW POINT OBS INTO THE FORECAST...WITH PREVIOUS
FORECAST LARGELY ON TRACK.
UPDATE ISSUED AT 1110 PM EST THU DEC 4 2014
FRESHENED UP THE HOURLY TEMPERATURES AND DEW POINTS TO JIVE BETTER
WITH THE LATEST TRENDS IN OBSERVATIONS. OTHERWISE...THE FORECAST IS
ON TRACK.
UPDATE ISSUED AT 810 PM EST THU DEC 4 2014
WIDESPREAD PRECIPITATION IS MOVING OUT AS FORCING RELAXES
TEMPORARILY. THE LATEST HRRR SEEMS TO HAVE A DECENT HANDLE ON THIS
AND WILL INCLUDE A LITTLE MORE OF A LULL IN THE ACTION THROUGH THE
OVERNIGHT HOURS...BEFORE INCREASING ONCE AGAIN BETWEEN 09 AND 12Z AS
THE WARM FRONT DRAWS NEARER FROM THE SOUTH. LOW TEMPERATURES HAVE
LIKELY ALREADY BEEN ESTABLISHED THIS EVENING AND EXPECT A GRADUAL
WARM UP THROUGH THE REST OF THE NIGHT...SLOWEST IN THE NORTH WHERE
LOCATIONS WILL REMAIN NORTH OF THE APPROACHING BOUNDARY THE LONGEST.
UPDATES HAVE BEEN SENT.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 340 PM EST THU DEC 4 2014
A WET FORECAST IS IN STORE FOR EASTERN KENTUCKY THROUGH SATURDAY. THE
MODELS ARE IN PRETTY GOOD AGREEMENT WITH THE OVERALL LARGE SCALE
WEATHER PATTERN ACROSS THE OHIO AND TENNESSEE VALLEY REGIONS. THE
PERIOD WILL BEGIN WITH A LARGE RIDGE OF SURFACE HIGH PRESSURE MOVING
OFF TO THE EAST ACROSS THE GREAT LAKES REGION...NEW ENGLAND AND THE
MID ATLANTIC CORRIDOR. AS THIS RIDGE CONTINUES TO PROGRESS...A WEAK
WARM FRONT WILL CONTINUE TO MEANDER ABOUT THE AREA. THIS FRONT
EXTENDS FROM AN AREA OF LOW PRESSURE THAT CONTINUES TO TAKE SHAPE
OVER THE SOUTHERN PLAINS. WIDESPREAD RAIN SHOWERS WILL CONTINUE TO
FORM AND MOVE ALONG THE FRONT AS WEAK WAVES OF LOW PRESSURE MOVE
ALONG IT FROM THE WEST. MODERATE RAINFALL WILL BE A GOOD POSSIBILITY
FROM FRIDAY AFTERNOON ONWARD...WITH FRIDAY NIGHT PROVIDING THE BEST
CHANCE FOR WIDESPREAD MODERATE RAIN AS THE PARENT LOW EJECTS QUICKLY
OUT OF THE PLAINS AND PUSHES A COLD FRONT THROUGH THE REGION FRIDAY
NIGHT.
WE COULD SEE SMALL SURGE OF WARMER AIR MOVE INTO THE AREA THIS
EVENING...AS THE FRONT MOVES FURTHER NORTH AND WINDS SHIFT TO THE
SOUTH. OVERNIGHT LOWS WILL LIKELY NOT BE MUCH COOLER THAN CURRENT
READINGS...AS WIDESPREAD CLOUD COVER SHOULD KEEP TEMPS FROM DROPPING
TOO MUCH OVERNIGHT. ONCE THE WARM FRONT BECOMES FIRMLY ESTABLISHED TO
OUR NORTH ON FRIDAY...TEMPERATURES ACROSS THE AREA SHOULD BE ABLE TO
SURGE A BIT...WITH MAX READINGS RANGING FROM THE UPPER 50S IN OUR
NORTH TO THE LOWER 60S IN OUR FAR SOUTH.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 340 PM EST THU DEC 4 2014
AN UPPER LEVEL SHORTWAVE WILL BE PASSING ACROSS THE OHIO RIVER
VALLEY REGION FROM WEST TO EAST TO START OFF THE DAY SATURDAY. THIS
WAVE OF ENERGY WILL RESULT IN A SURFACE LOW PRESSURE SYSTEM WHICH
SHOULD RIDE ALONG THE OHIO RIVER INTO 12Z SATURDAY AND EXIT BY
AFTERNOON. IT WILL ALSO PULL A COLD FRONT WITH IT...AND A LARGE AREA
OF PRECIPITATION STRETCHING FROM THE GULF OF MEXICO NE INTO CANADA.
WHILE MODELS ARE HAVING A LITTLE DIFFICULTY STILL MATCHING UP WITH
THEIR SOLUTIONS FOR TIMING AND COVERAGE...IT IS PRETTY WELL SETTLED
THAT A LARGE POOL OF MOISTURE/PRECIP WILL BE ACROSS THE REGION TO
START OUT 12Z SATURDAY...AND WILL SHIFT EASTWARD DURING THE
DAY...WITH THE PRECIP LINGERING SLIGHTLY LONGER INTO THE EVENING FOR
THE HIGHER UPSLOPE TERRAIN OF FAR EASTERN KY.
A LITTLE UNCERTAINTY ABOUT THE POSSIBILITY OF SOME ELEVATED
INSTABILITY AND ISOLATED THUNDERSTORM POTENTIAL AS WE HEAD INTO THE
DAY SATURDAY. LATEST MODEL RUNS ARE SHOWING A PRETTY STRONG
INVERSION SETTING UP BETWEEN 12 AND 18Z SATURDAY...AT LEAST IN THE
NW HALF OF THE CWA...WITH LITTLE INDICATION OF INSTABILITY ABOVE THE
INVERSION. IN ADDITION...WINDS WILL QUICKLY SHIFT TO THE NE SATURDAY
MORNING...CUTTING OFF ANY GOOD VEERING AND WARM AIR ADVECTION TO AID
IN THUNDERSTORM DEVELOPMENT. AS SUCH...WILL LEAVE MENTION OF THUNDER
OUT OF THE FORECAST FOR THE DAY SATURDAY. IT SEEMS AS THOUGH
NEIGHBORING OFFICES HAVE FOLLOWED SUIT IN THIS IDEA AS WELL.
BY SATURDAY NIGHT...RIDGING WILL BEGIN TO RIDE IN BEHIND THE
SHORTWAVE...WITH HIGH PRESSURE AND DRY AIR TAKING HOLD ACROSS THE
REGION. LATEST GFS FORECAST SOUNDINGS ARE SHOWING A POOL OF LOW
LEVEL MOISTURE THAT WILL REMAIN IN TACT BELOW A VERY STRONG
INVERSION SATURDAY NIGHT. THIS BOUNDARY LAYER MOISTURE WILL HOLD ON
UNTIL DRY AIR FINALLY MIXES DOWN TO THE SURFACE SUNDAY...WITH SOME
VERY IMPRESSIVELY DRY LOW LEVEL DEW POINTS EXPECTED SATURDAY NIGHT
AND INTO SUNDAY. WHILE THE HIGHEST TERRAIN WILL LIKELY TAP INTO
THESE VERY LOW DEW POINTS BY EARLY SUNDAY MORNING...DUE TO THEIR
ELEVATION...THE REST OF THE AREA WILL LIKELY FEEL THE LOW LEVEL
MOISTURE IN THE FORM OF A LOW STRATUS DECK...WHICH WILL DESCEND
TOWARDS THE SURFACE...BEFORE MIXING OUT SUNDAY MORNING WHEN
SOUNDINGS SHOW THE DRY AIR FINALLY REACHING THE SURFACE. THIS COULD
MEAN THAT SOME PEAKS BETWEEN JACKSON AND DORTON /THOSE NOT QUITE
HIGH ENOUGH TO TAP INTO THE DRIEST AIR/ COULD SEE SOME VISIBILITY
RESTRICTIONS DUE TO THE STRATUS DECK /I.E. STRATUS DECK WILL TOUCH
THE SURFACE AS FOG/. OTHERWISE...THE VALLEYS SHOULD REMAIN FOG FREE
DUE TO A COMBINATION OF DESCENT MIXING...COLD TEMPERATURES...NE
WINDS...AND THE FACT THAT THE CENTER OF HIGH PRESSURE IS WELL TO OUR
NE. SOUNDINGS ARE SHOWING THE DRY AIR TAKING HOLD AT THE SURFACE BY
SUNDAY AFTERNOON.
MEANWHILE...WINDS WILL SHIFT TO A MORE SRLY DIRECTION AT THE
SURFACE...AND CLOUDS WILL BEGIN TO THICKEN ALOFT THROUGH SUNDAY
NIGHT. THIS WILL BE THE PRECURSOR TO THE NEXT SHORT WAVE THAT IS
POISED TO MOVE ACROSS THE REGION. UNFORTUNATELY MODELS ARE SHOWING A
WIDE ARRAY OF SOLUTIONS NOT IN AGREEMENT WITH ONE ANOTHER BY THIS
POINT. WILL RELY ON THE BLENDED SOLUTION AT THIS POINT
FORWARD...ESPECIALLY GIVEN THE AMOUNT OF UNCERTAINTY IN THE UPPER
LEVELS. THIS UNCERTAINTY WILL TRANSLATE DOWN TO THE SURFACE...BOTH
IN THE TRACK OF THE ASSOCIATED SURFACE LOW PRESSURE SYSTEM...COLD
FRONT...AND ESPECIALLY IN THE EXTENT OF THE MOISTURE AND HOW IT WILL
AFFECT THE JKL CWA. ACCORDING TO ALL THE LONG RANGE MODELS...THE
HIGHEST CONCENTRATION OF MOISTURE WILL REMAIN WELL TO OUR
NORTH...AFFECTING THE GREAT LAKES REGION AND SLIGHTLY SOUTHWARD.
HOWEVER...THE ECMWF IS A BIT OF AN OUTLIER...SHOWING MOISTURE MOVING
MUCH FARTHER SOUTH...REACHING EASTERN KY MONDAY NIGHT AND INTO THE
DAY TUESDAY. MEANWHILE...THE GFS IS MUCH WEAKER...WITH HIGHER
HEIGHTS ACROSS THE REGION...AND NO PRECIP MAKING IT OUTSIDE OF THE
GREAT LAKES. IF THE ECMWF SOLUTION IS CORRECT...TEMPERATURES SHOULD
GENERALLY REMAIN ABOVE FREEZING DURING THIS SYSTEM...SO ANY
PRECIPITATION THAT DOES FALL WILL BE IN THE FORM OF RAIN. THE
EXCEPTION WILL DURING THE OVERNIGHT HOURS MONDAY NIGHT...WHEN SOME
OF THE HIGHEST RIDGES MAY DROP TO RIGHT AROUND FREEZING AND RAIN MAY
MIX WITH SOME SNOWFLAKES. THE SAME WILL HAPPEN ON TUESDAY
NIGHT...THOUGH IT IS LIKELY THAT MOST OF THE PRECIP WILL END BEFORE
TEMPERATURES DROP ENOUGH FOR SNOW TO MIX IN.
GENERAL CONSENSUS IS THAT RIDGING AND HIGH PRESSURE/DRY AIR WILL
OVERTAKE THE REGION ONCE MORE LATE TUESDAY NIGHT/WEDNESDAY AND
CONTINUE THROUGH MUCH OF REST OF THE FORECAST PERIOD...WITH
TEMPERATURES STAYING GENERALLY AT OR JUST SLIGHTLY BELOW NORMAL.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 137 AM EST FRI DEC 5 2014
CONDITIONS WERE HIGHLY VARIABLE ACROSS THE REGION AT THE START OF
THE PERIOD...WITH LARGELY VFR IN OUR SOUTHERN COUNTIES...AND THE
GREATEST PREVALENCE OF IFR IN THE NORTH. SOME OVERALL IMPROVEMENT IS
EXPECTED DURING THE NIGHT. DURING THE DAY ON FRIDAY...A DETERIORATION
TO MAINLY MVFR AND IFR IS EXPECTED AS SHOWERS DEVELOP.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...HAL
SHORT TERM...AR
LONG TERM...JMW
AVIATION...HAL
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
1115 AM CST FRI DEC 5 2014
.DISCUSSION...
18Z TAF ISSUANCE.
&&
.AVIATION...
IMPROVING CONDITIONS FROM THIS MORNING...WITH ALL SITES VFR VSBY.
STILL LINGERING MVFR CEILINGS AT AEX/LCH/LFT...BUT SHOULD IMPROVE
TO VFR SHORTLY. OTHERWISE...S WINDS 12-15 KTS WITH GUSTS OVER 20
KTS EXPECTED THIS AFTERNOON. CONDITIONS WILL DETERIORATE WITH
LOWERING OF CEILINGS THIS EVENING AREAWIDE...WITH DENSE FOG PRODUCING
LIFR VSBY/CEILINGS BY 06-08Z FOR BPT/LCH/LFT/ARA...AND NOT IMPROVING
UNTIL POST FRONTAL 16-17Z SAT.
DML
&&
.PREV DISCUSSION... /ISSUED 1034 AM CST FRI DEC 5 2014/
UPDATE...
A BAND OF SHOWERS CONTINUES TO MOVE NORTHEAST ACROSS INTERIOR
SOUTHEAST TEXAS. UPDATED POPS FOR THIS AREA TO ACCOUNT FOR THIS
BAND OF LATE MORNING SHOWERS WHICH IS NOT SHOWING MUCH OF AN
EASTWARD PROGRESS. THE REST OF THE FORECAST FOR TODAY LOOKS TO BE
ON TRACK. NO OTHER CHANGES NEEDED. DENSE FOG ADVISORY HAS EXPIRED
FOR THE NEARSHORE WATERS AND INLAND AREAS FROM LAKE CHARLES TO
BEAUMONT.
PREV DISCUSSION... /ISSUED 725 AM CST FRI DEC 5 2014/
UPDATE...
SOUTHEAST WINDS AROUND 8 MPH HAS PUSHED DENSE SEA FOG FROM THE
NEAR SHORE WATERS AND COASTAL LAKES...INTO LOWER SOUTHEAST TEXAS
AND SOUTHWEST LOUISIANA. OBSERVATIONS FROM LOCAL MEDIA WEB
CAMS...AND METAR OBSERVATIONS FROM CAMERON TO LAKE CHARLES TO
BEAUMONT...SHOW VISIBILITIES HAVE SETTLED IN AT AROUND 1/4 OF A
MILE. THEREFORE...HAVE ISSUED A DENSE FOG ADVISORY FOR THAT AREA
THROUGH 10 AM CST.
RUA
PREV DISCUSSION... /ISSUED 604 AM CST FRI DEC 5 2014/
DISCUSSION...
05/12Z TAF ISSUANCE.
AVIATION...
ABUNDANT MOISTURE IS PRODUCING A COMBINATION OF STRATUS/WDSPRD FOG
ACRS THE AREA. VISBYS VARY FM LESS THAN 1SM TO 4SM AT ALL SITES
WHILE LIFR CIGS AROUND 200 FT HAVE PREVAILED AT SRN AIRPORTS WITH
CIG HTS FLUCTUATING BETWEEN 200-500 FT AT AEX. EXPECT IMPROVING
CONDITIONS AFTER 14Z WITH VISBYS BECOMING VFR AND CIGS LIFTING TO
MVFR. KLCH RADAR SHOWS A FEW -SHRA DEVELOPING ACRS SE TX AND
SHOWERS SHOULD BECOME MORE WIDELY SCT DURING THE AFTN AS A
SHORTWAVE CROSSES THE REGION. INCLUDED VCSH AT BPT/LCH THIS
MORNING WITH VCSH AT REMAINING SITES BY AFTN. SLY WINDS WILL
INCREASE DURING THE DAY...WITH OCCASIONAL GUSTS TO NR 20 KT DURING
THE AFTN. WINDS WILL DIMINISH THIS EVENING...WITH CIGS LOWERING
AND FOG AGAIN DEVELOPING TONIGHT.
PREV DISCUSSION... /ISSUED 349 AM CST FRI DEC 5 2014/
DISCUSSION...
THE MAIN FORECAST ISSUE IN THE SHORT TERM IS THE FORMATION OF FOG
AS LIGHT SOUTHERLY WINDS BRING IN A WARM AND HUMID GULF AIR MASS.
CURRENTLY...WINDS ABOVE THE SURFACE ARE JUST STRONG ENOUGH TO KEEP
MOST OF THE LOW LEVEL MOISTURE IN THE FORM OF A VERY LOW STRATUS
DECK...WITH VISIBILITIES AT MOST LOCATIONS BETWEEN 1 AND 4 MILES.
A FEW LOCATIONS ESPECIALLY IN LOWER ACADIANA ARE HOVERING BETWEEN
1/4 AND 1/2 MILE...SO WILL CONTINUE TO MONITOR THIS LOCATION TO
SEE IF A DENSE FOG ADVISORY NEEDS TO BE ISSUED IF 1/4 MILE
VISIBILITY BECOMES MORE WIDESPREAD. ALSO...A FEW VERY LIGHT
SHOWERS HAVE DEVELOPED OVER EAST CENTRAL LOUISIANA...AS LIFT FROM SOUTHERN
STREAM SHORT WAVE BEGINS TO AFFECT THE FORECAST AREA.
RELATIVELY WARM AND HUMID CONDITIONS WILL CONTINUE THROUGH THE DAY
INTO TONIGHT. A SOUTHERN STREAM SHORT WAVE WILL ALSO CONTINUE TO
PUSH EASTWARD. MOISTURE PROFILES WILL CONTINUE TO INCREASE WITH
PRECIPITABLE WATER VALUES NEAR 1.5 INCHES BY AFTERNOON. LIFT FROM
THE SHORT WAVE SHOULD BE ENOUGH TO INITIATE SCATTERED...MAINLY
LIGHT...SHOWERS. PROGS DO SHOW SOME DECENT LOW LEVEL INSTABILITY
DURING THE AFTERNOON WITH CAPES BETWEEN 500 AND 1000 J/KG.
THEREFORE...A FEW THUNDERSTORMS COULD MIX IN WITH THE SHOWER
ACTIVITY...MAINLY NORTH OF HIGHWAY 190 CORRIDOR WHERE LIFT FROM
SHORT WAVE WILL BE GREATER. SOME FOG IS EXPECTED TO ALSO RE-
DEVELOP AWAY FROM SHOWER ACTIVITY TONIGHT. SOME FOG MAY BE DENSE
AT TIMES NEAR THE COAST.
WEAK COLD FRONT WILL MOVE ACROSS THE FORECAST AREA DURING THE DAY
ON SATURDAY...ENTERING NORTHERN SECTIONS DURING THE MID TO LATE
MORNING AND INTO THE COASTAL WATERS BY MID TO LATE AFTERNOON.
AGAIN SCATTERED SHOWER ACTIVITY IS EXPECTED TO ACCOMPANY THE
FRONT. INSTABILITY LOOKS WEAKER ON SATURDAY...SO WILL JUST MENTION
SHOWERS IN THE WEATHER GRID.
LOOKS LIKE SOUTHWEST FLOW ABOVE THE SURFACE WILL CONTINUE BEHIND
THE FRONT...SO OVER-RIDING LIGHT SHOWER ACTIVITY WILL CONTINUE
INTO SATURDAY NIGHT. A COOLER AND CLOUDY SUNDAY IS THEN
EXPECTED...WITH MAYBE A FEW LIGHT SHOWERS OVER THE WESTERN AND
NORTHERN ZONES INTO SUNDAY NIGHT...WITH THE PASSAGE OF THE NEXT
SOUTHERN STREAM SHORT WAVE.
AS THIS SHORT WAVE MOVES OFF TO THE EAST...A DEEPER NORTHWEST FLOW
IS EXPECTED...TO END UPGLIDE AND PUSH DEEPER MOISTURE AWAY FROM
THE AREA...ENDING RAIN CHANCES. THE UP-COMING WEEK THEN LOOKS ON
THE SEASONABLE SIDE...WITH MILD DAYS AND COOL NIGHTS.
RUA
MARINE...
LIGHT SOUTH WINDS ARE OCCURRING OVER THE COASTAL WATERS THIS EARLY
MORNING...HELPING PUSH WARM MOIST AIR OVER RELATIVELY COOLER
WATERS. THIS HAS RESULTED IN DENSE SEA FOG (VISIBILITIES BELOW 1 NM) FOR
MAINLY THE NEAR SHORE WATERS AND COASTAL LAKES AND BAYS.
OBSERVATIONS FURTHER OFFSHORE...DO NOT INDICATE ANY DENSE SEA FOG
AS TEMPERATURES HAVE WARMED THAT IS KEEPING ANY FOG LIGHT AND
PATCHY IN NATURE WITH MAINLY JUST LOW CLOUDS. THIS IS IN LINE WITH
WHAT RUC AND HRRR VISIBILITIES ARE SHOWING...THAT DENSE SEA FOG
WILL STAY IN THE NEAR SHORE WATERS THROUGH LATE MORNING. THEREFORE...HAVE
ADJUSTED THE MARINE DENSE FOG ADVISORY TO EXTEND IT THROUGH 10
CST...EXCEPT FOR THE OUTER WATERS...WHERE THE ADVISORY HAS BEEN DROPPED.
THE LIGHT ONSHORE FLOW WILL CONTINUE THROUGH THE NIGHT UNTIL A
WEAK COLD FRONT MOVES ACROSS THE COASTAL WATERS ON SATURDAY
AFTERNOON. THEREFORE...THERE IS ANOTHER LIKELIHOOD OF SOME DENSE
SEA FOG IN THE NEAR SHORE WATERS AGAIN TONIGHT.
LIGHT TO MODERATE NORTHERLY WINDS WILL DEVELOP BEHIND THE COLD
FRONT...AND THIS WILL HELP DISPERSE ANY REMAINING FOG AND END SEA
FOG FORMATION PROCESS AS COOLER AND DRIER AIR MASS MOVES INTO THE
REGION. THE OFFSHORE FLOW IS THEN EXPECTED THROUGH THE END OF THE
FORECAST PERIOD.
RUA
&&
.PRELIMINARY POINT TEMPS/POPS...
KLCH 62 73 51 62 47 / 30 30 20 10 10
KBPT 61 73 53 64 49 / 20 30 20 10 20
KAEX 61 71 46 59 42 / 40 30 10 10 20
KLFT 63 75 51 63 47 / 20 30 10 10 10
&&
.LCH WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
TX...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
1034 AM CST FRI DEC 5 2014
.UPDATE...
A BAND OF SHOWERS CONTINUES TO MOVE NORTHEAST ACROSS INTERIOR
SOUTHEAST TEXAS. UPDATED POPS FOR THIS AREA TO ACCOUNT FOR THIS
BAND OF LATE MORNING SHOWERS WHICH IS NOT SHOWING MUCH OF AN
EASTWARD PROGRESS. THE REST OF THE FORECAST FOR TODAY LOOKS TO BE
ON TRACK. NO OTHER CHANGES NEEDED. DENSE FOG ADVISORY HAS EXPIRED
FOR THE NEARSHORE WATERS AND INLAND AREAS FROM LAKE CHARLES TO
BEAUMONT.
&&
.PREV DISCUSSION... /ISSUED 725 AM CST FRI DEC 5 2014/
UPDATE...
SOUTHEAST WINDS AROUND 8 MPH HAS PUSHED DENSE SEA FOG FROM THE
NEAR SHORE WATERS AND COASTAL LAKES...INTO LOWER SOUTHEAST TEXAS
AND SOUTHWEST LOUISIANA. OBSERVATIONS FROM LOCAL MEDIA WEB
CAMS...AND METAR OBSERVATIONS FROM CAMERON TO LAKE CHARLES TO
BEAUMONT...SHOW VISIBILITIES HAVE SETTLED IN AT AROUND 1/4 OF A
MILE. THEREFORE...HAVE ISSUED A DENSE FOG ADVISORY FOR THAT AREA
THROUGH 10 AM CST.
RUA
PREV DISCUSSION... /ISSUED 604 AM CST FRI DEC 5 2014/
DISCUSSION...
05/12Z TAF ISSUANCE.
AVIATION...
ABUNDANT MOISTURE IS PRODUCING A COMBINATION OF STRATUS/WDSPRD FOG
ACRS THE AREA. VISBYS VARY FM LESS THAN 1SM TO 4SM AT ALL SITES
WHILE LIFR CIGS AROUND 200 FT HAVE PREVAILED AT SRN AIRPORTS WITH
CIG HTS FLUCTUATING BETWEEN 200-500 FT AT AEX. EXPECT IMPROVING
CONDITIONS AFTER 14Z WITH VISBYS BECOMING VFR AND CIGS LIFTING TO
MVFR. KLCH RADAR SHOWS A FEW -SHRA DEVELOPING ACRS SE TX AND
SHOWERS SHOULD BECOME MORE WIDELY SCT DURING THE AFTN AS A
SHORTWAVE CROSSES THE REGION. INCLUDED VCSH AT BPT/LCH THIS
MORNING WITH VCSH AT REMAINING SITES BY AFTN. SLY WINDS WILL
INCREASE DURING THE DAY...WITH OCCASIONAL GUSTS TO NR 20 KT DURING
THE AFTN. WINDS WILL DIMINISH THIS EVENING...WITH CIGS LOWERING
AND FOG AGAIN DEVELOPING TONIGHT.
PREV DISCUSSION... /ISSUED 349 AM CST FRI DEC 5 2014/
DISCUSSION...
THE MAIN FORECAST ISSUE IN THE SHORT TERM IS THE FORMATION OF FOG
AS LIGHT SOUTHERLY WINDS BRING IN A WARM AND HUMID GULF AIR MASS.
CURRENTLY...WINDS ABOVE THE SURFACE ARE JUST STRONG ENOUGH TO KEEP
MOST OF THE LOW LEVEL MOISTURE IN THE FORM OF A VERY LOW STRATUS
DECK...WITH VISIBILITIES AT MOST LOCATIONS BETWEEN 1 AND 4 MILES.
A FEW LOCATIONS ESPECIALLY IN LOWER ACADIANA ARE HOVERING BETWEEN
1/4 AND 1/2 MILE...SO WILL CONTINUE TO MONITOR THIS LOCATION TO
SEE IF A DENSE FOG ADVISORY NEEDS TO BE ISSUED IF 1/4 MILE
VISIBILITY BECOMES MORE WIDESPREAD. ALSO...A FEW VERY LIGHT
SHOWERS HAVE DEVELOPED OVER EAST CENTRAL LOUISIANA...AS LIFT FROM SOUTHERN
STREAM SHORT WAVE BEGINS TO AFFECT THE FORECAST AREA.
RELATIVELY WARM AND HUMID CONDITIONS WILL CONTINUE THROUGH THE DAY
INTO TONIGHT. A SOUTHERN STREAM SHORT WAVE WILL ALSO CONTINUE TO
PUSH EASTWARD. MOISTURE PROFILES WILL CONTINUE TO INCREASE WITH
PRECIPITABLE WATER VALUES NEAR 1.5 INCHES BY AFTERNOON. LIFT FROM
THE SHORT WAVE SHOULD BE ENOUGH TO INITIATE SCATTERED...MAINLY
LIGHT...SHOWERS. PROGS DO SHOW SOME DECENT LOW LEVEL INSTABILITY
DURING THE AFTERNOON WITH CAPES BETWEEN 500 AND 1000 J/KG.
THEREFORE...A FEW THUNDERSTORMS COULD MIX IN WITH THE SHOWER
ACTIVITY...MAINLY NORTH OF HIGHWAY 190 CORRIDOR WHERE LIFT FROM
SHORT WAVE WILL BE GREATER. SOME FOG IS EXPECTED TO ALSO RE-
DEVELOP AWAY FROM SHOWER ACTIVITY TONIGHT. SOME FOG MAY BE DENSE
AT TIMES NEAR THE COAST.
WEAK COLD FRONT WILL MOVE ACROSS THE FORECAST AREA DURING THE DAY
ON SATURDAY...ENTERING NORTHERN SECTIONS DURING THE MID TO LATE
MORNING AND INTO THE COASTAL WATERS BY MID TO LATE AFTERNOON.
AGAIN SCATTERED SHOWER ACTIVITY IS EXPECTED TO ACCOMPANY THE
FRONT. INSTABILITY LOOKS WEAKER ON SATURDAY...SO WILL JUST MENTION
SHOWERS IN THE WEATHER GRID.
LOOKS LIKE SOUTHWEST FLOW ABOVE THE SURFACE WILL CONTINUE BEHIND
THE FRONT...SO OVER-RIDING LIGHT SHOWER ACTIVITY WILL CONTINUE
INTO SATURDAY NIGHT. A COOLER AND CLOUDY SUNDAY IS THEN
EXPECTED...WITH MAYBE A FEW LIGHT SHOWERS OVER THE WESTERN AND
NORTHERN ZONES INTO SUNDAY NIGHT...WITH THE PASSAGE OF THE NEXT
SOUTHERN STREAM SHORT WAVE.
AS THIS SHORT WAVE MOVES OFF TO THE EAST...A DEEPER NORTHWEST FLOW
IS EXPECTED...TO END UPGLIDE AND PUSH DEEPER MOISTURE AWAY FROM
THE AREA...ENDING RAIN CHANCES. THE UP-COMING WEEK THEN LOOKS ON
THE SEASONABLE SIDE...WITH MILD DAYS AND COOL NIGHTS.
RUA
MARINE...
LIGHT SOUTH WINDS ARE OCCURRING OVER THE COASTAL WATERS THIS EARLY
MORNING...HELPING PUSH WARM MOIST AIR OVER RELATIVELY COOLER
WATERS. THIS HAS RESULTED IN DENSE SEA FOG (VISIBILITIES BELOW 1 NM) FOR
MAINLY THE NEAR SHORE WATERS AND COASTAL LAKES AND BAYS.
OBSERVATIONS FURTHER OFFSHORE...DO NOT INDICATE ANY DENSE SEA FOG
AS TEMPERATURES HAVE WARMED THAT IS KEEPING ANY FOG LIGHT AND
PATCHY IN NATURE WITH MAINLY JUST LOW CLOUDS. THIS IS IN LINE WITH
WHAT RUC AND HRRR VISIBILITIES ARE SHOWING...THAT DENSE SEA FOG
WILL STAY IN THE NEAR SHORE WATERS THROUGH LATE MORNING. THEREFORE...HAVE
ADJUSTED THE MARINE DENSE FOG ADVISORY TO EXTEND IT THROUGH 10
CST...EXCEPT FOR THE OUTER WATERS...WHERE THE ADVISORY HAS BEEN DROPPED.
THE LIGHT ONSHORE FLOW WILL CONTINUE THROUGH THE NIGHT UNTIL A
WEAK COLD FRONT MOVES ACROSS THE COASTAL WATERS ON SATURDAY
AFTERNOON. THEREFORE...THERE IS ANOTHER LIKELIHOOD OF SOME DENSE
SEA FOG IN THE NEAR SHORE WATERS AGAIN TONIGHT.
LIGHT TO MODERATE NORTHERLY WINDS WILL DEVELOP BEHIND THE COLD
FRONT...AND THIS WILL HELP DISPERSE ANY REMAINING FOG AND END SEA
FOG FORMATION PROCESS AS COOLER AND DRIER AIR MASS MOVES INTO THE
REGION. THE OFFSHORE FLOW IS THEN EXPECTED THROUGH THE END OF THE
FORECAST PERIOD.
RUA
&&
.PRELIMINARY POINT TEMPS/POPS...
KLCH 74 62 73 51 / 30 30 30 20
KBPT 75 61 73 53 / 20 20 30 20
KAEX 76 61 71 46 / 40 40 30 10
KLFT 76 63 75 51 / 30 20 30 10
&&
.LCH WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
TX...NONE.
GM...NONE.
&&
$$
PUBLIC/MARINE...06
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
725 AM CST FRI DEC 5 2014
.UPDATE...
SOUTHEAST WINDS AROUND 8 MPH HAS PUSHED DENSE SEA FOG FROM THE
NEAR SHORE WATERS AND COASTAL LAKES...INTO LOWER SOUTHEAST TEXAS
AND SOUTHWEST LOUISIANA. OBSERVATIONS FROM LOCAL MEDIA WEB
CAMS...AND METAR OBSERVATIONS FROM CAMERON TO LAKE CHARLES TO
BEAUMONT...SHOW VISIBILITIES HAVE SETTLED IN AT AROUND 1/4 OF A
MILE. THEREFORE...HAVE ISSUED A DENSE FOG ADVISORY FOR THAT AREA
THROUGH 10 AM CST.
RUA
&&
.PREV DISCUSSION... /ISSUED 604 AM CST FRI DEC 5 2014/
DISCUSSION...
05/12Z TAF ISSUANCE.
AVIATION...
ABUNDANT MOISTURE IS PRODUCING A COMBINATION OF STRATUS/WDSPRD FOG
ACRS THE AREA. VISBYS VARY FM LESS THAN 1SM TO 4SM AT ALL SITES
WHILE LIFR CIGS AROUND 200 FT HAVE PREVAILED AT SRN AIRPORTS WITH
CIG HTS FLUCTUATING BETWEEN 200-500 FT AT AEX. EXPECT IMPROVING
CONDITIONS AFTER 14Z WITH VISBYS BECOMING VFR AND CIGS LIFTING TO
MVFR. KLCH RADAR SHOWS A FEW -SHRA DEVELOPING ACRS SE TX AND
SHOWERS SHOULD BECOME MORE WIDELY SCT DURING THE AFTN AS A
SHORTWAVE CROSSES THE REGION. INCLUDED VCSH AT BPT/LCH THIS
MORNING WITH VCSH AT REMAINING SITES BY AFTN. SLY WINDS WILL
INCREASE DURING THE DAY...WITH OCCASIONAL GUSTS TO NR 20 KT DURING
THE AFTN. WINDS WILL DIMINISH THIS EVENING...WITH CIGS LOWERING
AND FOG AGAIN DEVELOPING TONIGHT.
PREV DISCUSSION... /ISSUED 349 AM CST FRI DEC 5 2014/
DISCUSSION...
THE MAIN FORECAST ISSUE IN THE SHORT TERM IS THE FORMATION OF FOG
AS LIGHT SOUTHERLY WINDS BRING IN A WARM AND HUMID GULF AIR MASS.
CURRENTLY...WINDS ABOVE THE SURFACE ARE JUST STRONG ENOUGH TO KEEP
MOST OF THE LOW LEVEL MOISTURE IN THE FORM OF A VERY LOW STRATUS
DECK...WITH VISIBILITIES AT MOST LOCATIONS BETWEEN 1 AND 4 MILES.
A FEW LOCATIONS ESPECIALLY IN LOWER ACADIANA ARE HOVERING BETWEEN
1/4 AND 1/2 MILE...SO WILL CONTINUE TO MONITOR THIS LOCATION TO
SEE IF A DENSE FOG ADVISORY NEEDS TO BE ISSUED IF 1/4 MILE
VISIBILITY BECOMES MORE WIDESPREAD. ALSO...A FEW VERY LIGHT
SHOWERS HAVE DEVELOPED OVER EAST CENTRAL LOUISIANA...AS LIFT FROM SOUTHERN
STREAM SHORT WAVE BEGINS TO AFFECT THE FORECAST AREA.
RELATIVELY WARM AND HUMID CONDITIONS WILL CONTINUE THROUGH THE DAY
INTO TONIGHT. A SOUTHERN STREAM SHORT WAVE WILL ALSO CONTINUE TO
PUSH EASTWARD. MOISTURE PROFILES WILL CONTINUE TO INCREASE WITH
PRECIPITABLE WATER VALUES NEAR 1.5 INCHES BY AFTERNOON. LIFT FROM
THE SHORT WAVE SHOULD BE ENOUGH TO INITIATE SCATTERED...MAINLY
LIGHT...SHOWERS. PROGS DO SHOW SOME DECENT LOW LEVEL INSTABILITY
DURING THE AFTERNOON WITH CAPES BETWEEN 500 AND 1000 J/KG.
THEREFORE...A FEW THUNDERSTORMS COULD MIX IN WITH THE SHOWER
ACTIVITY...MAINLY NORTH OF HIGHWAY 190 CORRIDOR WHERE LIFT FROM
SHORT WAVE WILL BE GREATER. SOME FOG IS EXPECTED TO ALSO RE-
DEVELOP AWAY FROM SHOWER ACTIVITY TONIGHT. SOME FOG MAY BE DENSE
AT TIMES NEAR THE COAST.
WEAK COLD FRONT WILL MOVE ACROSS THE FORECAST AREA DURING THE DAY
ON SATURDAY...ENTERING NORTHERN SECTIONS DURING THE MID TO LATE
MORNING AND INTO THE COASTAL WATERS BY MID TO LATE AFTERNOON.
AGAIN SCATTERED SHOWER ACTIVITY IS EXPECTED TO ACCOMPANY THE
FRONT. INSTABILITY LOOKS WEAKER ON SATURDAY...SO WILL JUST MENTION
SHOWERS IN THE WEATHER GRID.
LOOKS LIKE SOUTHWEST FLOW ABOVE THE SURFACE WILL CONTINUE BEHIND
THE FRONT...SO OVER-RIDING LIGHT SHOWER ACTIVITY WILL CONTINUE
INTO SATURDAY NIGHT. A COOLER AND CLOUDY SUNDAY IS THEN
EXPECTED...WITH MAYBE A FEW LIGHT SHOWERS OVER THE WESTERN AND
NORTHERN ZONES INTO SUNDAY NIGHT...WITH THE PASSAGE OF THE NEXT
SOUTHERN STREAM SHORT WAVE.
AS THIS SHORT WAVE MOVES OFF TO THE EAST...A DEEPER NORTHWEST FLOW
IS EXPECTED...TO END UPGLIDE AND PUSH DEEPER MOISTURE AWAY FROM
THE AREA...ENDING RAIN CHANCES. THE UP-COMING WEEK THEN LOOKS ON
THE SEASONABLE SIDE...WITH MILD DAYS AND COOL NIGHTS.
RUA
MARINE...
LIGHT SOUTH WINDS ARE OCCURRING OVER THE COASTAL WATERS THIS EARLY
MORNING...HELPING PUSH WARM MOIST AIR OVER RELATIVELY COOLER
WATERS. THIS HAS RESULTED IN DENSE SEA FOG (VISIBILITIES BELOW 1 NM) FOR
MAINLY THE NEAR SHORE WATERS AND COASTAL LAKES AND BAYS.
OBSERVATIONS FURTHER OFFSHORE...DO NOT INDICATE ANY DENSE SEA FOG
AS TEMPERATURES HAVE WARMED THAT IS KEEPING ANY FOG LIGHT AND
PATCHY IN NATURE WITH MAINLY JUST LOW CLOUDS. THIS IS IN LINE WITH
WHAT RUC AND HRRR VISIBILITIES ARE SHOWING...THAT DENSE SEA FOG
WILL STAY IN THE NEAR SHORE WATERS THROUGH LATE MORNING. THEREFORE...HAVE
ADJUSTED THE MARINE DENSE FOG ADVISORY TO EXTEND IT THROUGH 10
CST...EXCEPT FOR THE OUTER WATERS...WHERE THE ADVISORY HAS BEEN DROPPED.
THE LIGHT ONSHORE FLOW WILL CONTINUE THROUGH THE NIGHT UNTIL A
WEAK COLD FRONT MOVES ACROSS THE COASTAL WATERS ON SATURDAY
AFTERNOON. THEREFORE...THERE IS ANOTHER LIKELIHOOD OF SOME DENSE
SEA FOG IN THE NEAR SHORE WATERS AGAIN TONIGHT.
LIGHT TO MODERATE NORTHERLY WINDS WILL DEVELOP BEHIND THE COLD
FRONT...AND THIS WILL HELP DISPERSE ANY REMAINING FOG AND END SEA
FOG FORMATION PROCESS AS COOLER AND DRIER AIR MASS MOVES INTO THE
REGION. THE OFFSHORE FLOW IS THEN EXPECTED THROUGH THE END OF THE
FORECAST PERIOD.
RUA
&&
.PRELIMINARY POINT TEMPS/POPS...
KLCH 74 62 73 51 62 / 30 30 30 20 10
KBPT 75 61 73 53 64 / 20 20 30 20 10
KAEX 76 61 71 46 59 / 40 40 30 10 10
KLFT 76 63 75 51 63 / 30 20 30 10 10
&&
.LCH WATCHES/WARNINGS/ADVISORIES...
LA...DENSE FOG ADVISORY UNTIL 10 AM CST THIS MORNING FOR THE
FOLLOWING ZONES: CALCASIEU...EAST CAMERON...WEST CAMERON.
TX...DENSE FOG ADVISORY UNTIL 10 AM CST THIS MORNING FOR THE
FOLLOWING ZONES: JEFFERSON...ORANGE.
GM...DENSE FOG ADVISORY UNTIL 10 AM CST THIS MORNING FOR THE
FOLLOWING ZONES: CALCASIEU LAKE...COASTAL WATERS FROM
CAMERON LA TO HIGH ISLAND TX OUT 20 NM...COASTAL WATERS
FROM INTRACOASTAL CITY TO CAMERON LA OUT 20 NM...COASTAL
WATERS FROM LOWER ATCHAFALAYA RIVER TO INTRACOASTAL CITY LA
OUT 20 NM...SABINE LAKE...VERMILION BAY.
&&
$$
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
604 AM CST FRI DEC 5 2014
.DISCUSSION...
05/12Z TAF ISSUANCE.
&&
.AVIATION...
ABUNDANT MOISTURE IS PRODUCING A COMBINATION OF STRATUS/WDSPRD FOG
ACRS THE AREA. VISBYS VARY FM LESS THAN 1SM TO 4SM AT ALL SITES
WHILE LIFR CIGS AROUND 200 FT HAVE PREVAILED AT SRN AIRPORTS WITH
CIG HTS FLUCTUATING BETWEEN 200-500 FT AT AEX. EXPECT IMPROVING
CONDITIONS AFTER 14Z WITH VISBYS BECOMING VFR AND CIGS LIFTING TO
MVFR. KLCH RADAR SHOWS A FEW -SHRA DEVELOPING ACRS SE TX AND
SHOWERS SHOULD BECOME MORE WIDELY SCT DURING THE AFTN AS A
SHORTWAVE CROSSES THE REGION. INCLUDED VCSH AT BPT/LCH THIS
MORNING WITH VCSH AT REMAINING SITES BY AFTN. SLY WINDS WILL
INCREASE DURING THE DAY...WITH OCCASIONAL GUSTS TO NR 20 KT DURING
THE AFTN. WINDS WILL DIMINISH THIS EVENING...WITH CIGS LOWERING
AND FOG AGAIN DEVELOPING TONIGHT.
&&
.PREV DISCUSSION... /ISSUED 349 AM CST FRI DEC 5 2014/
DISCUSSION...
THE MAIN FORECAST ISSUE IN THE SHORT TERM IS THE FORMATION OF FOG
AS LIGHT SOUTHERLY WINDS BRING IN A WARM AND HUMID GULF AIR MASS.
CURRENTLY...WINDS ABOVE THE SURFACE ARE JUST STRONG ENOUGH TO KEEP
MOST OF THE LOW LEVEL MOISTURE IN THE FORM OF A VERY LOW STRATUS
DECK...WITH VISIBILITIES AT MOST LOCATIONS BETWEEN 1 AND 4 MILES.
A FEW LOCATIONS ESPECIALLY IN LOWER ACADIANA ARE HOVERING BETWEEN
1/4 AND 1/2 MILE...SO WILL CONTINUE TO MONITOR THIS LOCATION TO
SEE IF A DENSE FOG ADVISORY NEEDS TO BE ISSUED IF 1/4 MILE
VISIBILITY BECOMES MORE WIDESPREAD. ALSO...A FEW VERY LIGHT
SHOWERS HAVE DEVELOPED OVER EAST CENTRAL LOUISIANA...AS LIFT FROM SOUTHERN
STREAM SHORT WAVE BEGINS TO AFFECT THE FORECAST AREA.
RELATIVELY WARM AND HUMID CONDITIONS WILL CONTINUE THROUGH THE DAY
INTO TONIGHT. A SOUTHERN STREAM SHORT WAVE WILL ALSO CONTINUE TO
PUSH EASTWARD. MOISTURE PROFILES WILL CONTINUE TO INCREASE WITH
PRECIPITABLE WATER VALUES NEAR 1.5 INCHES BY AFTERNOON. LIFT FROM
THE SHORT WAVE SHOULD BE ENOUGH TO INITIATE SCATTERED...MAINLY
LIGHT...SHOWERS. PROGS DO SHOW SOME DECENT LOW LEVEL INSTABILITY
DURING THE AFTERNOON WITH CAPES BETWEEN 500 AND 1000 J/KG.
THEREFORE...A FEW THUNDERSTORMS COULD MIX IN WITH THE SHOWER
ACTIVITY...MAINLY NORTH OF HIGHWAY 190 CORRIDOR WHERE LIFT FROM
SHORT WAVE WILL BE GREATER. SOME FOG IS EXPECTED TO ALSO RE-
DEVELOP AWAY FROM SHOWER ACTIVITY TONIGHT. SOME FOG MAY BE DENSE
AT TIMES NEAR THE COAST.
WEAK COLD FRONT WILL MOVE ACROSS THE FORECAST AREA DURING THE DAY
ON SATURDAY...ENTERING NORTHERN SECTIONS DURING THE MID TO LATE
MORNING AND INTO THE COASTAL WATERS BY MID TO LATE AFTERNOON.
AGAIN SCATTERED SHOWER ACTIVITY IS EXPECTED TO ACCOMPANY THE
FRONT. INSTABILITY LOOKS WEAKER ON SATURDAY...SO WILL JUST MENTION
SHOWERS IN THE WEATHER GRID.
LOOKS LIKE SOUTHWEST FLOW ABOVE THE SURFACE WILL CONTINUE BEHIND
THE FRONT...SO OVER-RIDING LIGHT SHOWER ACTIVITY WILL CONTINUE
INTO SATURDAY NIGHT. A COOLER AND CLOUDY SUNDAY IS THEN
EXPECTED...WITH MAYBE A FEW LIGHT SHOWERS OVER THE WESTERN AND
NORTHERN ZONES INTO SUNDAY NIGHT...WITH THE PASSAGE OF THE NEXT
SOUTHERN STREAM SHORT WAVE.
AS THIS SHORT WAVE MOVES OFF TO THE EAST...A DEEPER NORTHWEST FLOW
IS EXPECTED...TO END UPGLIDE AND PUSH DEEPER MOISTURE AWAY FROM
THE AREA...ENDING RAIN CHANCES. THE UP-COMING WEEK THEN LOOKS ON
THE SEASONABLE SIDE...WITH MILD DAYS AND COOL NIGHTS.
RUA
MARINE...
LIGHT SOUTH WINDS ARE OCCURRING OVER THE COASTAL WATERS THIS EARLY
MORNING...HELPING PUSH WARM MOIST AIR OVER RELATIVELY COOLER
WATERS. THIS HAS RESULTED IN DENSE SEA FOG (VISIBILITIES BELOW 1 NM) FOR
MAINLY THE NEAR SHORE WATERS AND COASTAL LAKES AND BAYS.
OBSERVATIONS FURTHER OFFSHORE...DO NOT INDICATE ANY DENSE SEA FOG
AS TEMPERATURES HAVE WARMED THAT IS KEEPING ANY FOG LIGHT AND
PATCHY IN NATURE WITH MAINLY JUST LOW CLOUDS. THIS IS IN LINE WITH
WHAT RUC AND HRRR VISIBILITIES ARE SHOWING...THAT DENSE SEA FOG
WILL STAY IN THE NEAR SHORE WATERS THROUGH LATE MORNING. THEREFORE...HAVE
ADJUSTED THE MARINE DENSE FOG ADVISORY TO EXTEND IT THROUGH 10
CST...EXCEPT FOR THE OUTER WATERS...WHERE THE ADVISORY HAS BEEN DROPPED.
THE LIGHT ONSHORE FLOW WILL CONTINUE THROUGH THE NIGHT UNTIL A
WEAK COLD FRONT MOVES ACROSS THE COASTAL WATERS ON SATURDAY
AFTERNOON. THEREFORE...THERE IS ANOTHER LIKELIHOOD OF SOME DENSE
SEA FOG IN THE NEAR SHORE WATERS AGAIN TONIGHT.
LIGHT TO MODERATE NORTHERLY WINDS WILL DEVELOP BEHIND THE COLD
FRONT...AND THIS WILL HELP DISPERSE ANY REMAINING FOG AND END SEA
FOG FORMATION PROCESS AS COOLER AND DRIER AIR MASS MOVES INTO THE
REGION. THE OFFSHORE FLOW IS THEN EXPECTED THROUGH THE END OF THE
FORECAST PERIOD.
RUA
&&
.PRELIMINARY POINT TEMPS/POPS...
KLCH 74 62 72 49 / 30 30 30 10
KBPT 75 61 73 53 / 20 20 30 20
KAEX 76 61 71 46 / 40 40 30 10
KLFT 76 63 74 51 / 30 20 30 10
&&
.LCH WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
TX...NONE.
GM...NONE.
&&
$$
PUBLIC/MARINE...07
AVIATION...24
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
349 AM CST FRI DEC 5 2014
.DISCUSSION...
THE MAIN FORECAST ISSUE IN THE SHORT TERM IS THE FORMATION OF FOG
AS LIGHT SOUTHERLY WINDS BRING IN A WARM AND HUMID GULF AIR MASS.
CURRENTLY...WINDS ABOVE THE SURFACE ARE JUST STRONG ENOUGH TO KEEP
MOST OF THE LOW LEVEL MOISTURE IN THE FORM OF A VERY LOW STRATUS
DECK...WITH VISIBILITIES AT MOST LOCATIONS BETWEEN 1 AND 4 MILES.
A FEW LOCATIONS ESPECIALLY IN LOWER ACADIANA ARE HOVERING BETWEEN
1/4 AND 1/2 MILE...SO WILL CONTINUE TO MONITOR THIS LOCATION TO
SEE IF A DENSE FOG ADVISORY NEEDS TO BE ISSUED IF 1/4 MILE
VISIBILITY BECOMES MORE WIDESPREAD. ALSO...A FEW VERY LIGHT
SHOWERS HAVE DEVELOPED OVER EAST CENTRAL LOUISIANA...AS LIFT FROM SOUTHERN
STREAM SHORT WAVE BEGINS TO AFFECT THE FORECAST AREA.
RELATIVELY WARM AND HUMID CONDITIONS WILL CONTINUE THROUGH THE DAY
INTO TONIGHT. A SOUTHERN STREAM SHORT WAVE WILL ALSO CONTINUE TO
PUSH EASTWARD. MOISTURE PROFILES WILL CONTINUE TO INCREASE WITH
PRECIPITABLE WATER VALUES NEAR 1.5 INCHES BY AFTERNOON. LIFT FROM
THE SHORT WAVE SHOULD BE ENOUGH TO INITIATE SCATTERED...MAINLY
LIGHT...SHOWERS. PROGS DO SHOW SOME DECENT LOW LEVEL INSTABILITY
DURING THE AFTERNOON WITH CAPES BETWEEN 500 AND 1000 J/KG.
THEREFORE...A FEW THUNDERSTORMS COULD MIX IN WITH THE SHOWER
ACTIVITY...MAINLY NORTH OF HIGHWAY 190 CORRIDOR WHERE LIFT FROM
SHORT WAVE WILL BE GREATER. SOME FOG IS EXPECTED TO ALSO RE-
DEVELOP AWAY FROM SHOWER ACTIVITY TONIGHT. SOME FOG MAY BE DENSE
AT TIMES NEAR THE COAST.
WEAK COLD FRONT WILL MOVE ACROSS THE FORECAST AREA DURING THE DAY
ON SATURDAY...ENTERING NORTHERN SECTIONS DURING THE MID TO LATE
MORNING AND INTO THE COASTAL WATERS BY MID TO LATE AFTERNOON.
AGAIN SCATTERED SHOWER ACTIVITY IS EXPECTED TO ACCOMPANY THE
FRONT. INSTABILITY LOOKS WEAKER ON SATURDAY...SO WILL JUST MENTION
SHOWERS IN THE WEATHER GRID.
LOOKS LIKE SOUTHWEST FLOW ABOVE THE SURFACE WILL CONTINUE BEHIND
THE FRONT...SO OVER-RIDING LIGHT SHOWER ACTIVITY WILL CONTINUE
INTO SATURDAY NIGHT. A COOLER AND CLOUDY SUNDAY IS THEN
EXPECTED...WITH MAYBE A FEW LIGHT SHOWERS OVER THE WESTERN AND
NORTHERN ZONES INTO SUNDAY NIGHT...WITH THE PASSAGE OF THE NEXT
SOUTHERN STREAM SHORT WAVE.
AS THIS SHORT WAVE MOVES OFF TO THE EAST...A DEEPER NORTHWEST FLOW
IS EXPECTED...TO END UPGLIDE AND PUSH DEEPER MOISTURE AWAY FROM
THE AREA...ENDING RAIN CHANCES. THE UP-COMING WEEK THEN LOOKS ON
THE SEASONABLE SIDE...WITH MILD DAYS AND COOL NIGHTS.
RUA
&&
.MARINE...
LIGHT SOUTH WINDS ARE OCCURRING OVER THE COASTAL WATERS THIS EARLY
MORNING...HELPING PUSH WARM MOIST AIR OVER RELATIVELY COOLER
WATERS. THIS HAS RESULTED IN DENSE SEA FOG (VISIBILITIES BELOW 1 NM) FOR
MAINLY THE NEAR SHORE WATERS AND COASTAL LAKES AND BAYS.
OBSERVATIONS FURTHER OFFSHORE...DO NOT INDICATE ANY DENSE SEA FOG
AS TEMPERATURES HAVE WARMED THAT IS KEEPING ANY FOG LIGHT AND
PATCHY IN NATURE WITH MAINLY JUST LOW CLOUDS. THIS IS IN LINE WITH
WHAT RUC AND HRRR VISIBILITIES ARE SHOWING...THAT DENSE SEA FOG
WILL STAY IN THE NEAR SHORE WATERS THROUGH LATE MORNING. THEREFORE...HAVE
ADJUSTED THE MARINE DENSE FOG ADVISORY TO EXTEND IT THROUGH 10
CST...EXCEPT FOR THE OUTER WATERS...WHERE THE ADVISORY HAS BEEN DROPPED.
THE LIGHT ONSHORE FLOW WILL CONTINUE THROUGH THE NIGHT UNTIL A
WEAK COLD FRONT MOVES ACROSS THE COASTAL WATERS ON SATURDAY
AFTERNOON. THEREFORE...THERE IS ANOTHER LIKELIHOOD OF SOME DENSE
SEA FOG IN THE NEAR SHORE WATERS AGAIN TONIGHT.
LIGHT TO MODERATE NORTHERLY WINDS WILL DEVELOP BEHIND THE COLD
FRONT...AND THIS WILL HELP DISPERSE ANY REMAINING FOG AND END SEA
FOG FORMATION PROCESS AS COOLER AND DRIER AIR MASS MOVES INTO THE
REGION. THE OFFSHORE FLOW IS THEN EXPECTED THROUGH THE END OF THE
FORECAST PERIOD.
RUA
&&
.PRELIMINARY POINT TEMPS/POPS...
KLCH 74 62 73 51 62 / 30 30 30 20 10
KBPT 75 61 73 53 64 / 20 20 30 20 10
KAEX 76 61 71 46 59 / 40 40 30 10 10
KLFT 76 63 75 51 63 / 30 20 30 10 10
&&
.LCH WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
TX...NONE.
GM...DENSE FOG ADVISORY UNTIL 10 AM CST THIS MORNING FOR THE
FOLLOWING ZONES: CALCASIEU LAKE...COASTAL WATERS FROM
CAMERON LA TO HIGH ISLAND TX OUT 20 NM...COASTAL WATERS
FROM INTRACOASTAL CITY TO CAMERON LA OUT 20 NM...COASTAL
WATERS FROM LOWER ATCHAFALAYA RIVER TO INTRACOASTAL CITY LA
OUT 20 NM...SABINE LAKE...VERMILION BAY.
&&
$$
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
651 AM EST FRI DEC 5 2014
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 330 AM EST FRI DEC 5 2014
FAIR WEATHER WITH SEASONABLE TEMPERATURES WILL CONTINUE TODAY
BEFORE A LOW PRESSURE SYSTEM MOVING INTO OHIO VALLEY REGION BRINGS
JUST A SMALL CHANCE OF LIGHT RAIN OR MIXED LIGHT RAIN AND LIGHT
SNOW INTO FAR SOUTHERN LOWER MICHIGAN NEAR TO SOUTH OF INTERSTATE
94 TONIGHT. FAIR WEATHER WILL RETURN THIS WEEKEND.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 330 AM EST FRI DEC 5 2014
FAIR WX WILL CONTINUE TODAY WITH MOSTLY CLOUDY SKIES AND
SEASONABLE MAX TEMPS REACHING THE MID TO UPPER 30S. A CONSENSUS OF
LATEST SHORT RANGE GUIDANCE CONTINUES TO SUGGEST THAT THE
NORTHERMOST PERIPHERY OF THE PCPN SHIELD ASSOCIATED WITH LOW
PRESSURE TRACKING THROUGH THE OH VALLEY REGION MAY JUST CLIP OUR
FAR SOUTHERN COUNTIES ALONG I-94 THIS EVENING AND OVERNIGHT. PCPN
WILL FALL IN THE FORM OF LIGHT RAIN OR A VERY LIGHT RAIN/SNOW MIX
WITH NO SNOW ACCUMULATION.
ANOTHER HIGH PRESSURE RIDGE WILL BUILD IN FOR THE WEEKEND AND
BRING FAIR WX WITH PARTLY CLOUDY SKIES AND SEASONABLY COOL
TEMPERATURES.
.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY)
ISSUED AT 330 AM EST FRI DEC 5 2014
FOR THE MOST PART WARMER THAN NORMAL TEMPERATURES ARE FAVORED WELL
PAST THIS FORECAST TIME FRAME. HOWEVER... WE DO HAVE A THE TREAT OF
SIGNIFICANT LAKE ENHANCED SNOW EVENT NONE THE LESS MONDAY NIGHT INTO
TUESDAY. BEYOND THAT QUIET WEATHER WITH A SLOW WARMING TREND SHOULD
BE EXPECTED. HOWEVER...BEFORE THAT HAPPENS WE GET MORE WINTER
WEATHER MONDAY NIGHT INTO TUESDAY.
WHAT WE HAVE TONIGHT IS A NON-RECURVING TYPHOON...HAGUPIT...WITH 125
KNOT WINDS HEADING TOWARD CENTRAL INDONESIA. NON-RECURVING TYPHOONS
HAVE A WARMING IMPACT ON THE 5 TO 10 DAY TEMPERATURE PATTEN FOR THE
CENTRAL AND EASTERN UNITED STATES. THIS WOULD SUGGEST LARGE SCALE
UPPER LEVEL RIDGING SHOULD PREVAIL FROM THE MIDDLE OF NEXT WEEK INTO
THE WEEKEND. NOT TO SURPRISINGLY THE ECMWF AND GFS DO GO IN THAT
DIRECTION. THE OTHER ASPECT OF THE LARGE SCALE CIRCULATION THAT
SUPPORTS THE IDEA OF UPPER LEVEL RIDING FROM THE MIDDLE OF NEXT WEEK
INTO THE WEEKEND IS THE EXTENDED EAST ASIA JET WHICH FEATURES 180 TO
200 KNOT WINDS FROM JUST SOUTH OF THE KOREAN PENINSULA TO JUST EAST
OF THE DATE LINE...NEAR 45 NORTH. AS THAT JET CORE COMES TOWARD
WESTERN NORTH AMERICA IT WILL PUMP UP THE WESTERN RIDGE AND DEEPEN
THE DOWN STREAM TROUGH. THIS CHAIN OF EVENTS SUPPORTS THE ECMWF
FORECAST MORE SO THAN THE GFS WITH TO ME AS THE GFS IS NOT DIGGING
THE SHORTWAVE NEARLY AS MUCH AS IT SHOULD BE.
THE RESULT OF THIS IN THE SHORTER TERM IS WE GET MUCH COLDER AIR AND
A SIGNIFICANT LAKE ENHANCED SNOW EVENT MONDAY NIGHT INTO TUESDAY.
THE
GFS IS TO WEAK WITH THIS SYSTEM AND KICKS IT OUT TO QUICKLY. WE
COULD BE LOOKING AT 3 TO 5 INCHES OF SNOW WEST OF US-131 MONDAY
NIGHT INTO TUESDAY.
BEYOND THAT... THAT UPPER RIDGING STARTS TO SET IN SO A SLOW WARM UP
FOLLOWS.
WEEK TWO FORECAST...(FRIDAY THROUGH THE FOLLOWING THURSDAY)
HERE IS WERE WE MAY SEE A MAJOR TURN AROUND IN THE LONG WAVE PATTERN
AND BRING WINTER BACK INTO SOUTHWEST MICHIGAN. AS IT TURNS OUT THE
MJO IS IN QUAD 5 DOING VERY NICELY. THIS SUGGEST WARM WEATHER FOR
MOST OF THE CONUS. BOTH THE ECMWF AND GFS LONG RANGE FORECAST BRING
THE MJO TO QUAD 7-8 AROUND THE END OF WEEK TWO. THIS BRINGS COLD
WEATHER ACROSS MOST OF THE CENTRAL AND EASTERN UNITED STATES. THE
ECMWF 51 REMEMBER ENSEMBLES FROM THE 4TH DO INDEED SHOW THIS
HAPPENING AS DEEP TROUGH RETURNS TO THE EASTERN CONUS BY THE END
OF NEXT WEEK. SO EXPECT WARMER THAN NORMAL TEMPERATURES TILL AROUND
WEDNESDAY OF NEXT WEEK... THEN WINTER COMES BACK
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 651 AM EST FRI DEC 5 2014
IT SEEMS TO ME IFR CIGS WILL MOVE INTO ALL OF THE TAF SITES BY MID
TO LATE AFTERNOON. WINDS WILL NOT BE ALL THAT STRONG. THERE IS AN
AREA OF RAIN HEADING TOWARD LOWER MICHIGAN BUT THERE IS SOME
QUESTION AS TO HOW FAR NORTH IT WILL GET. I USED THE HRRR AS MY
GUIDE AND IT BRINGS THE RAIN (TO WARM FOR SNOW OF FREEZING
ANYTHING BY THEN) BY 21Z OF THE I-94 TAF SITES. THE RAIN WILL PULL
OUT LATER IN THE EVENING AS A LOW PRESSURE SYSTEM DEVELOPS WELL
SOUTH OF THE AREA TURNING THE WINDS TO THE NORTH. I DID NOT DO
MUCH WITH FOG BUT THERE MAY BE SOME IFR FOG IN THE I-94 TAFS
TONIGHT.
&&
.MARINE...
ISSUED AT 330 AM EST FRI DEC 5 2014
FAIRLY MINIMAL WIND AND WAVE ACTION IS ANTICIPATED TODAY THROUGH
TONIGHT. BRISK NORTH TO NORTHEAST WINDS SATURDAY WILL CAUSE WAVE
HEIGHTS TO INCREASE SOMEWHAT.
&&
.HYDROLOGY...
ISSUED AT 330 AM EST FRI DEC 5 2014
NO HYDRO ISSUES THROUGH THE WEEKEND WITH PREDOMINANTLY DRY
WEATHER.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
SYNOPSIS...LAURENS
SHORT TERM...LAURENS
LONG TERM...WDM
AVIATION...WDM
HYDROLOGY...LAURENS
MARINE...LAURENS
UPDATED FOR NEW AVIATION FORECAST DISCUSSION BELOW.
UPDATE ISSUED AT 544 AM CST FRI DEC 5 2014
UPDATED AVIATION SECTION BELOW.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 425 AM CST FRI DEC 5 2014
A CLOUDY START TO THE DAY FOR SOME AHEAD OF A WEAK COLD FRONT MOVING
THROUGH THIS AFTERNOON. BEHIND THE FRONT LIGHT WINDS AND CLEAR SKIES
AS AN AREA OF HIGH PRESSURE MOVES ACROSS THE AREA ON SATURDAY.
TEMPERATURES SEASONABLE...BUT NOT AS WARM AS ORIGINALLY ANTICIPATED
IN PREVIOUS FORECASTS.
TODAY...PATCHY FOG/LOW STRATUS CLOUDS IN THE MORNING QUICKLY
CLEARING BEHIND THE FRONT IN THE AFTERNOON. MAIN CHALLENGE WITH THIS
FORECAST IS THE SKY AND WEATHER THROUGH THE MORNING. SHORT-TERM
GUIDANCE INCLUDING RAP...HRRR...LOCAL DLH WRF...AND HOP WRF
ENSEMBLE HAVE BEEN CONSISTENT IN DEPICTING A CORRIDOR OF ENHANCED
LOW LEVEL MOISTURE FROM BRAINERD TO THE I-35 CORRIDOR AT THE
SOUTHERN PORTION OF THE CWA NORTH THROUGH THE NORTH SHORE OF LAKE
SUPERIOR. THIS WILL TRANSLATE INTO LOW TO MID LEVEL CLOUD COVER
AND PROBABLY SOME PATCHY FOG IN THE MORNING HOURS...WITH CLEARING
RAPIDLY BEHIND THE APPROACHING COLD FRONT. LAMP AND GFS/NAM MOS
HAVE NOT BEEN CATCHING ONTO THE STRATUS/FOG THIS MORNING...BUT
LEANED TOWARDS THE SHORT TERM HIGH RESOLUTION MODELS OVER THE
STATISTICAL GUIDANCE. THERE COULD ALSO BE SOME LIGHT SNOW/FLURRIES
IN PARTS OF NORTHWEST WISCONSIN WHERE LARGE SCALE LIFT WILL
INTERSECT WITH THE LOW LEVEL MOISTURE...BUT CONFIDENCE IS LOW.
TEMPS WERE A CHALLENGE SINCE MORNING CLOUDS WILL LIMIT HEATING FOR
SOME AREAS. LATEST HRRR IS AGGRESSIVE WITH KEEPING FOG/STRATUS
ALONG THE I-35 CORRIDOR THROUGH PORTIONS OF THE NORTH SHORE...AND
GIVEN CLIMO OF THESE TYPES OF EVENTS COULD DEFINITELY SEE CLOUDS
HANGING AROUND CAUSING A SHARP TEMP GRADIENT. COLD AIR BEHIND THE
FRONT DOES NOT APPEAR ALL TOO IMPRESSIVE...AND IF CLOUD COVER
CLEARS EARLIER THAN ANTICIPATED HIGH TEMPERATURES MAY BE WARMER
THAN CURRENTLY FORECAST.
TONIGHT...CLEAR SKIES AND LIGHT WINDS. LOW TEMPS IN THE SINGLE
DIGITS ABOVE ZERO...EXCEPT AROUND THE RAINY LAKE AREA WHERE TEMPS
WILL DIP TO NEAR OR JUST BELOW ZERO.
SATURDAY...MOSTLY SUNNY WITH NEAR-CALM WINDS. IF HIGH PRESSURE AND
ASSOCIATED LOW/MID LEVEL RIDGE PASSES EAST A BIT QUICKER THAN
CURRENTLY ANTICIPATED TEMPS COULD WARM UP TO NEAR FREEZING...BUT
OTHERWISE CURRENT FORECAST IS FOR HIGHS IN THE LOW TO MID 20S AS THE
CANADIAN AIR MASS IS CENTERED OVER THE NORTHLAND. INCREASING CLOUDS
LATE IN THE BORDERLAND AREA.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 425 AM CST FRI DEC 5 2014
AFTER A QUIET SATURDAY NIGHT...OUR NEXT SIGNIFICANT WEATHER MAKER
WILL MOVE INTO THE AREA SUNDAY AND AFFECT THE AREA THROUGH MONDAY.
A FAIRLY STRONG SHORTWAVE IN THE WEST-NORTHWEST UPPER LEVEL FLOW
WILL MOVE ACROSS THE UPPER MIDWEST. LOTS OF WARM AIR WILL BE
ADVECTED INTO THE AREA AHEAD OF THIS SYSTEM...WITH 850MB
TEMPERATURES UP INTO THE -2C TO 2 ABOVE BY SUNDAY 12Z. IN THE
CONTINUING WARM AIR ADVECTION...SHOWERS WILL DEVELOP IN THE STREAM
OF MOISTURE AND LIFT AS THE 850MB WARM FRONT MOVES THROUGH THE
AREA. WITH THE WARM AIR ALOFT...WE SHOULD GET SOME SLEET ALONG WITH
SNOW SHOWERS AS THE SURFACE TEMPS SHOULD STILL BE NEAR OR JUST BELOW
FREEZING. AT THIS TIME...IT DOES NOT LOOK LIKE IT WILL GET WARM
ENOUGH FOR FULL MELTING ALOFT AND FREEZING RAIN AT THE SURFACE...BUT
THESE LATEST RUNS ARE COOLER ALOFT THAN PREVIOUS RUNS AND WE WILL
HAVE TO WATCH THIS CAREFULLY TO SEE IF THIS CHANGES. THINGS WOULD
NOT HAVE TO CHANGE MUCH ALOFT TO GET A BRIEF PERIOD OF FREEZING RAIN
BEFORE EVAPORATIVE COOLING TURNS IT BACK TO SLEET/SNOW...AND WOULD
NOT BE SURPRISED TO SEE THIS. SUNDAY NIGHT THE UPPER LOW COMES
ACROSS THE AREA...AND WHILE IT KEEPS THE WARM LAYER ALOFT OVER THE
AREA...IT IS COOL ENOUGH FOR OUR PRECIPITATION TO BE ALL
SNOW...THOUGH ONCE AGAIN IT WOULD NOT HAVE TO CHANGE MUCH FOR SOME
MORE SLEET. IT IS NOT UNTIL MONDAY MORNING THAT THE FULL COLD AIR
SURGES INTO THE AREA TO PUT SOME REAL CERTAINTY IN THE PRECIPITATION
TYPE. SUNDAY AND SUNDAY NIGHT THE WARM AIR KEEPS OUR SNOW WATER
RATIOS VERY LOW...AND EXPECT MINOR SNOW ACCUMULATIONS DURING THESE
PERIODS...BUT MONDAY THE COLDER AIR SHOULD ALLOW SOME HIGHER RATIOS
AND BETTER SNOWFALL AMOUNTS...JUST AS THE SNOW IS ENDING. EVENT
TOTALS WILL BE HIGHEST OVER THE ARROWHEAD WHERE 1-2 INCHES ARE
POSSIBLE...WITH LESSER AMOUNTS FARTHER SOUTH. HAVE MAINLY USED THE
GFS AND ECMWF FOR THIS FORECAST. THE NAM AND GEM ARE FARTHER NORTH
AND HAVE USED LESS OF THEM.
A STRONG SURFACE RIDGE SHOULD BUILD INTO THE AREA ONCE AGAIN FOR
MONDAY NIGHT AND TUESDAY...AND DEPENDING ON THE CLOUD COVER WE MAY
NEED TO LOWER TEMPS MORE. OTHERWISE...THERE SHOULD BE DRY
CONDITIONS. WARM AIR ADVECTION SETS IN FOR WEDNESDAY...WHICH MAY
BRING SOME PRECIP...BUT THERE IS LOTS OF MODEL DISAGREEMENT. HAVE
LEFT SOME SLIGHT CHANCE POPS IN FOR WEDNESDAY FOR NOW. STRONG UPPER
LEVEL RIDGING BUILDS INTO THE AREA FOR THE LATTER PART OF THE WORK
WEEK...BRINGING DRIER AND MUCH WARMER CONDITIONS. BY THURSDAY HIGHS
WILL BE WELL ABOVE NORMAL WITH HIGHS IN THE MID 30S...AND WARMER YET
EXPECTED FOR THE NEXT WEEKEND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1134 AM CST FRI DEC 5 2014
SKIES WERE GRADUALLY CLEARING FROM NW TO SE ACROSS THE AREA THIS
MORNING. THE LOW CLOUDS LINGERED IN THE KDLH AND KHYR AREAS. THE
SKIES SHOULD CLEAR IN THE KDLH AREA SHORTLY...AND IT WILL TAKE A
WHILE LONGER THIS AFTERNOON FOR KHYR TO IMPROVE TO VFR. SOME BR/HZ
WILL LINGER FOR A TIME AS WELL. ANOTHER AREA OF LOW CLOUDS WAS
MOVING SOUTHEASTWARD ACROSS SOUTH CENTRAL CANADA...AND SHOULD MOVE
INTO THE CWA...BUT BASED ON HIGH RESOLUTION OBJECTIVE GUIDANCE WAS
THINKING IT WOULD BREAK UP ENOUGH TO BE MORE OF A SCATTERED DECK.
WILL CONTINUE TO WATCH THIS AREA NOW MOVING THROUGH SOUTHERN
MANITOBA IN CASE IT HOLDS TOGETHER.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 28 10 23 15 / 0 0 0 0
INL 25 0 19 15 / 0 0 0 10
BRD 30 9 22 16 / 0 0 0 0
HYR 31 13 25 15 / 0 0 0 0
ASX 32 15 26 17 / 0 0 0 0
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
UPDATE...DAP
SHORT TERM...JJM
LONG TERM...LE
AVIATION...DAP
AREA FORECAST DISCUSSION
NWS DULUTH MN
545 AM CST FRI DEC 5 2014
.UPDATE...
ISSUED AT 544 AM CST FRI DEC 5 2014
UPDATED AVIATION SECTION BELOW.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 425 AM CST FRI DEC 5 2014
A CLOUDY START TO THE DAY FOR SOME AHEAD OF A WEAK COLD FRONT MOVING
THROUGH THIS AFTERNOON. BEHIND THE FRONT LIGHT WINDS AND CLEAR SKIES
AS AN AREA OF HIGH PRESSURE MOVES ACROSS THE AREA ON SATURDAY.
TEMPERATURES SEASONABLE...BUT NOT AS WARM AS ORIGINALLY ANTICIPATED
IN PREVIOUS FORECASTS.
TODAY...PATCHY FOG/LOW STRATUS CLOUDS IN THE MORNING QUICKLY
CLEARING BEHIND THE FRONT IN THE AFTERNOON. MAIN CHALLENGE WITH THIS
FORECAST IS THE SKY AND WEATHER THROUGH THE MORNING. SHORT-TERM
GUIDANCE INCLUDING RAP...HRRR...LOCAL DLH WRF...AND HOP WRF
ENSEMBLE HAVE BEEN CONSISTENT IN DEPICTING A CORRIDOR OF ENHANCED
LOW LEVEL MOISTURE FROM BRAINERD TO THE I-35 CORRIDOR AT THE
SOUTHERN PORTION OF THE CWA NORTH THROUGH THE NORTH SHORE OF LAKE
SUPERIOR. THIS WILL TRANSLATE INTO LOW TO MID LEVEL CLOUD COVER
AND PROBABLY SOME PATCHY FOG IN THE MORNING HOURS...WITH CLEARING
RAPIDLY BEHIND THE APPROACHING COLD FRONT. LAMP AND GFS/NAM MOS
HAVE NOT BEEN CATCHING ONTO THE STRATUS/FOG THIS MORNING...BUT
LEANED TOWARDS THE SHORT TERM HIGH RESOLUTION MODELS OVER THE
STATISTICAL GUIDANCE. THERE COULD ALSO BE SOME LIGHT SNOW/FLURRIES
IN PARTS OF NORTHWEST WISCONSIN WHERE LARGE SCALE LIFT WILL
INTERSECT WITH THE LOW LEVEL MOISTURE...BUT CONFIDENCE IS LOW.
TEMPS WERE A CHALLENGE SINCE MORNING CLOUDS WILL LIMIT HEATING FOR
SOME AREAS. LATEST HRRR IS AGGRESSIVE WITH KEEPING FOG/STRATUS
ALONG THE I-35 CORRIDOR THROUGH PORTIONS OF THE NORTH SHORE...AND
GIVEN CLIMO OF THESE TYPES OF EVENTS COULD DEFINITELY SEE CLOUDS
HANGING AROUND CAUSING A SHARP TEMP GRADIENT. COLD AIR BEHIND THE
FRONT DOES NOT APPEAR ALL TOO IMPRESSIVE...AND IF CLOUD COVER
CLEARS EARLIER THAN ANTICIPATED HIGH TEMPERATURES MAY BE WARMER
THAN CURRENTLY FORECAST.
TONIGHT...CLEAR SKIES AND LIGHT WINDS. LOW TEMPS IN THE SINGLE
DIGITS ABOVE ZERO...EXCEPT AROUND THE RAINY LAKE AREA WHERE TEMPS
WILL DIP TO NEAR OR JUST BELOW ZERO.
SATURDAY...MOSTLY SUNNY WITH NEAR-CALM WINDS. IF HIGH PRESSURE AND
ASSOCIATED LOW/MID LEVEL RIDGE PASSES EAST A BIT QUICKER THAN
CURRENTLY ANTICIPATED TEMPS COULD WARM UP TO NEAR FREEZING...BUT
OTHERWISE CURRENT FORECAST IS FOR HIGHS IN THE LOW TO MID 20S AS THE
CANADIAN AIR MASS IS CENTERED OVER THE NORTHLAND. INCREASING CLOUDS
LATE IN THE BORDERLAND AREA.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 425 AM CST FRI DEC 5 2014
AFTER A QUIET SATURDAY NIGHT...OUR NEXT SIGNIFICANT WEATHER MAKER
WILL MOVE INTO THE AREA SUNDAY AND AFFECT THE AREA THROUGH MONDAY.
A FAIRLY STRONG SHORTWAVE IN THE WEST-NORTHWEST UPPER LEVEL FLOW
WILL MOVE ACROSS THE UPPER MIDWEST. LOTS OF WARM AIR WILL BE
ADVECTED INTO THE AREA AHEAD OF THIS SYSTEM...WITH 850MB
TEMPERATURES UP INTO THE -2C TO 2 ABOVE BY SUNDAY 12Z. IN THE
CONTINUING WARM AIR ADVECTION...SHOWERS WILL DEVELOP IN THE STREAM
OF MOISTURE AND LIFT AS THE 850MB WARM FRONT MOVES THROUGH THE
AREA. WITH THE WARM AIR ALOFT...WE SHOULD GET SOME SLEET ALONG WITH
SNOW SHOWERS AS THE SURFACE TEMPS SHOULD STILL BE NEAR OR JUST BELOW
FREEZING. AT THIS TIME...IT DOES NOT LOOK LIKE IT WILL GET WARM
ENOUGH FOR FULL MELTING ALOFT AND FREEZING RAIN AT THE SURFACE...BUT
THESE LATEST RUNS ARE COOLER ALOFT THAN PREVIOUS RUNS AND WE WILL
HAVE TO WATCH THIS CAREFULLY TO SEE IF THIS CHANGES. THINGS WOULD
NOT HAVE TO CHANGE MUCH ALOFT TO GET A BRIEF PERIOD OF FREEZING RAIN
BEFORE EVAPORATIVE COOLING TURNS IT BACK TO SLEET/SNOW...AND WOULD
NOT BE SURPRISED TO SEE THIS. SUNDAY NIGHT THE UPPER LOW COMES
ACROSS THE AREA...AND WHILE IT KEEPS THE WARM LAYER ALOFT OVER THE
AREA...IT IS COOL ENOUGH FOR OUR PRECIPITATION TO BE ALL
SNOW...THOUGH ONCE AGAIN IT WOULD NOT HAVE TO CHANGE MUCH FOR SOME
MORE SLEET. IT IS NOT UNTIL MONDAY MORNING THAT THE FULL COLD AIR
SURGES INTO THE AREA TO PUT SOME REAL CERTAINTY IN THE PRECIPITATION
TYPE. SUNDAY AND SUNDAY NIGHT THE WARM AIR KEEPS OUR SNOW WATER
RATIOS VERY LOW...AND EXPECT MINOR SNOW ACCUMULATIONS DURING THESE
PERIODS...BUT MONDAY THE COLDER AIR SHOULD ALLOW SOME HIGHER RATIOS
AND BETTER SNOWFALL AMOUNTS...JUST AS THE SNOW IS ENDING. EVENT
TOTALS WILL BE HIGHEST OVER THE ARROWHEAD WHERE 1-2 INCHES ARE
POSSIBLE...WITH LESSER AMOUNTS FARTHER SOUTH. HAVE MAINLY USED THE
GFS AND ECMWF FOR THIS FORECAST. THE NAM AND GEM ARE FARTHER NORTH
AND HAVE USED LESS OF THEM.
A STRONG SURFACE RIDGE SHOULD BUILD INTO THE AREA ONCE AGAIN FOR
MONDAY NIGHT AND TUESDAY...AND DEPENDING ON THE CLOUD COVER WE MAY
NEED TO LOWER TEMPS MORE. OTHERWISE...THERE SHOULD BE DRY
CONDITIONS. WARM AIR ADVECTION SETS IN FOR WEDNESDAY...WHICH MAY
BRING SOME PRECIP...BUT THERE IS LOTS OF MODEL DISAGREEMENT. HAVE
LEFT SOME SLIGHT CHANCE POPS IN FOR WEDNESDAY FOR NOW. STRONG UPPER
LEVEL RIDGING BUILDS INTO THE AREA FOR THE LATTER PART OF THE WORK
WEEK...BRINGING DRIER AND MUCH WARMER CONDITIONS. BY THURSDAY HIGHS
WILL BE WELL ABOVE NORMAL WITH HIGHS IN THE MID 30S...AND WARMER YET
EXPECTED FOR THE NEXT WEEKEND.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 544 AM CST FRI DEC 5 2014
MVFR STRATUS OVER THE EASTERN TERMINALS THIS MORNING WITH CIGS
AROUND 15HFT FOR KHYR AND KDLH EXPECTED TO LINGER AND PERHAPS
EXPAND TO KHIB THIS MORNING AHEAD OF A COLD FRONT DUE TO MOVE
THROUGH THE AREA DURING THE LATE MORNING AND AFTERNOON. MVFR
VISIBILITIES IN FOG POSSIBLE FOR KHYR ALSO POSSIBLE THROUGH 17Z.
FRONT MOVES THROUGH AND TURNS WINDS TO NORTHWEST CLEARING OUT
STRATUS AND FOG...AND EXPECT CONDITIONS TO RETURN TO VFR BEHIND
FRONT. AN AREA OF CLOUDS WITH PERHAPS MVFR CIGS TO MOVE ACROSS
ARROWHEAD LATE THIS AFTERNOON AND EVENING AFFECTING AS EARLY AS
22Z WITH MVFR CIGS. CIGS VARIABLE IN THESE CLOUDS AT THIS TIME
OVER SASKATCHEWAN AND MANITOBA...SO WILL HAVE TO MONITOR THESE
CLOUDS AS THEY MOVE CLOSER TO THE TERMINALS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 27 10 23 15 / 10 0 0 0
INL 25 0 19 15 / 0 0 0 10
BRD 27 9 22 16 / 0 0 0 0
HYR 31 13 25 15 / 20 0 0 0
ASX 31 15 26 17 / 10 0 0 0
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...SMALL CRAFT ADVISORY UNTIL 10 AM CST THIS MORNING FOR LSZ140-141.
&&
$$
UPDATE...LE
SHORT TERM...JJM
LONG TERM...LE
AVIATION...LE
AREA FORECAST DISCUSSION
NWS DULUTH MN
425 AM CST FRI DEC 5 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 425 AM CST FRI DEC 5 2014
A CLOUDY START TO THE DAY FOR SOME AHEAD OF A WEAK COLD FRONT MOVING
THROUGH THIS AFTERNOON. BEHIND THE FRONT LIGHT WINDS AND CLEAR SKIES
AS AN AREA OF HIGH PRESSURE MOVES ACROSS THE AREA ON SATURDAY.
TEMPERATURES SEASONABLE...BUT NOT AS WARM AS ORIGINALLY ANTICIPATED
IN PREVIOUS FORECASTS.
TODAY...PATCHY FOG/LOW STRATUS CLOUDS IN THE MORNING QUICKLY
CLEARING BEHIND THE FRONT IN THE AFTERNOON. MAIN CHALLENGE WITH THIS
FORECAST IS THE SKY AND WEATHER THROUGH THE MORNING. SHORT-TERM
GUIDANCE INCLUDING RAP...HRRR...LOCAL DLH WRF...AND HOP WRF
ENSEMBLE HAVE BEEN CONSISTENT IN DEPICTING A CORRIDOR OF ENHANCED
LOW LEVEL MOISTURE FROM BRAINERD TO THE I-35 CORRIDOR AT THE
SOUTHERN PORTION OF THE CWA NORTH THROUGH THE NORTH SHORE OF LAKE
SUPERIOR. THIS WILL TRANSLATE INTO LOW TO MID LEVEL CLOUD COVER
AND PROBABLY SOME PATCHY FOG IN THE MORNING HOURS...WITH CLEARING
RAPIDLY BEHIND THE APPROACHING COLD FRONT. LAMP AND GFS/NAM MOS
HAVE NOT BEEN CATCHING ONTO THE STRATUS/FOG THIS MORNING...BUT
LEANED TOWARDS THE SHORT TERM HIGH RESOLUTION MODELS OVER THE
STATISTICAL GUIDANCE. THERE COULD ALSO BE SOME LIGHT SNOW/FLURRIES
IN PARTS OF NORTHWEST WISCONSIN WHERE LARGE SCALE LIFT WILL
INTERSECT WITH THE LOW LEVEL MOISTURE...BUT CONFIDENCE IS LOW.
TEMPS WERE A CHALLENGE SINCE MORNING CLOUDS WILL LIMIT HEATING FOR
SOME AREAS. LATEST HRRR IS AGGRESSIVE WITH KEEPING FOG/STRATUS
ALONG THE I-35 CORRIDOR THROUGH PORTIONS OF THE NORTH SHORE...AND
GIVEN CLIMO OF THESE TYPES OF EVENTS COULD DEFINITELY SEE CLOUDS
HANGING AROUND CAUSING A SHARP TEMP GRADIENT. COLD AIR BEHIND THE
FRONT DOES NOT APPEAR ALL TOO IMPRESSIVE...AND IF CLOUD COVER
CLEARS EARLIER THAN ANTICIPATED HIGH TEMPERATURES MAY BE WARMER
THAN CURRENTLY FORECAST.
TONIGHT...CLEAR SKIES AND LIGHT WINDS. LOW TEMPS IN THE SINGLE
DIGITS ABOVE ZERO...EXCEPT AROUND THE RAINY LAKE AREA WHERE TEMPS
WILL DIP TO NEAR OR JUST BELOW ZERO.
SATURDAY...MOSTLY SUNNY WITH NEAR-CALM WINDS. IF HIGH PRESSURE AND
ASSOCIATED LOW/MID LEVEL RIDGE PASSES EAST A BIT QUICKER THAN
CURRENTLY ANTICIPATED TEMPS COULD WARM UP TO NEAR FREEZING...BUT
OTHERWISE CURRENT FORECAST IS FOR HIGHS IN THE LOW TO MID 20S AS THE
CANADIAN AIR MASS IS CENTERED OVER THE NORTHLAND. INCREASING CLOUDS
LATE IN THE BORDERLAND AREA.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 425 AM CST FRI DEC 5 2014
AFTER A QUIET SATURDAY NIGHT...OUR NEXT SIGNIFICANT WEATHER MAKER
WILL MOVE INTO THE AREA SUNDAY AND AFFECT THE AREA THROUGH MONDAY.
A FAIRLY STRONG SHORTWAVE IN THE WEST-NORTHWEST UPPER LEVEL FLOW
WILL MOVE ACROSS THE UPPER MIDWEST. LOTS OF WARM AIR WILL BE
ADVECTED INTO THE AREA AHEAD OF THIS SYSTEM...WITH 850MB
TEMPERATURES UP INTO THE -2C TO 2 ABOVE BY SUNDAY 12Z. IN THE
CONTINUING WARM AIR ADVECTION...SHOWERS WILL DEVELOP IN THE STREAM
OF MOISTURE AND LIFT AS THE 850MB WARM FRONT MOVES THROUGH THE
AREA. WITH THE WARM AIR ALOFT...WE SHOULD GET SOME SLEET ALONG WITH
SNOW SHOWERS AS THE SURFACE TEMPS SHOULD STILL BE NEAR OR JUST BELOW
FREEZING. AT THIS TIME...IT DOES NOT LOOK LIKE IT WILL GET WARM
ENOUGH FOR FULL MELTING ALOFT AND FREEZING RAIN AT THE SURFACE...BUT
THESE LATEST RUNS ARE COOLER ALOFT THAN PREVIOUS RUNS AND WE WILL
HAVE TO WATCH THIS CAREFULLY TO SEE IF THIS CHANGES. THINGS WOULD
NOT HAVE TO CHANGE MUCH ALOFT TO GET A BRIEF PERIOD OF FREEZING RAIN
BEFORE EVAPORATIVE COOLING TURNS IT BACK TO SLEET/SNOW...AND WOULD
NOT BE SURPRISED TO SEE THIS. SUNDAY NIGHT THE UPPER LOW COMES
ACROSS THE AREA...AND WHILE IT KEEPS THE WARM LAYER ALOFT OVER THE
AREA...IT IS COOL ENOUGH FOR OUR PRECIPITATION TO BE ALL
SNOW...THOUGH ONCE AGAIN IT WOULD NOT HAVE TO CHANGE MUCH FOR SOME
MORE SLEET. IT IS NOT UNTIL MONDAY MORNING THAT THE FULL COLD AIR
SURGES INTO THE AREA TO PUT SOME REAL CERTAINTY IN THE PRECIPITATION
TYPE. SUNDAY AND SUNDAY NIGHT THE WARM AIR KEEPS OUR SNOW WATER
RATIOS VERY LOW...AND EXPECT MINOR SNOW ACCUMULATIONS DURING THESE
PERIODS...BUT MONDAY THE COLDER AIR SHOULD ALLOW SOME HIGHER RATIOS
AND BETTER SNOWFALL AMOUNTS...JUST AS THE SNOW IS ENDING. EVENT
TOTALS WILL BE HIGHEST OVER THE ARROWHEAD WHERE 1-2 INCHES ARE
POSSIBLE...WITH LESSER AMOUNTS FARTHER SOUTH. HAVE MAINLY USED THE
GFS AND ECMWF FOR THIS FORECAST. THE NAM AND GEM ARE FARTHER NORTH
AND HAVE USED LESS OF THEM.
A STRONG SURFACE RIDGE SHOULD BUILD INTO THE AREA ONCE AGAIN FOR
MONDAY NIGHT AND TUESDAY...AND DEPENDING ON THE CLOUD COVER WE MAY
NEED TO LOWER TEMPS MORE. OTHERWISE...THERE SHOULD BE DRY
CONDITIONS. WARM AIR ADVECTION SETS IN FOR WEDNESDAY...WHICH MAY
BRING SOME PRECIP...BUT THERE IS LOTS OF MODEL DISAGREEMENT. HAVE
LEFT SOME SLIGHT CHANCE POPS IN FOR WEDNESDAY FOR NOW. STRONG UPPER
LEVEL RIDGING BUILDS INTO THE AREA FOR THE LATTER PART OF THE WORK
WEEK...BRINGING DRIER AND MUCH WARMER CONDITIONS. BY THURSDAY HIGHS
WILL BE WELL ABOVE NORMAL WITH HIGHS IN THE MID 30S...AND WARMER YET
EXPECTED FOR THE NEXT WEEKEND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1137 PM CST THU DEC 4 2014
MVFR CEILINGS WERE SURGING NORTH ALONG THE MINNESOTA/WISCONSIN
BORDER AND INTO NORTHERN WISCONSIN LATE THIS EVENING. THIS WILL CONTINUE
OVERNIGHT AND CEILINGS WILL GRADUALLY LOWER AS WELL. IFR CEILINGS
WILL DEVELOP AS THE NIGHT PROGRESSES AND THERE MAY BE SOME PATCHY
FOG AS WELL. IN ADDITION THERE MAY BE SOME PATCHY FREEZING DRIZZLE
IN SPOTS...MAINLY IMPACTING KHYR LATE. THERE WERE SOME WEAK ECHOES
MOVING OUT OF SOUTHEAST NORTH DAKOTA...BUT CONTINUED TO WEAKEN.
SOME BRIEF VERY LIGHT FREEZING DRIZZLE MAY PASS NEAR KBRD AS WELL
LATE.
BUFR SOUNDINGS SHOW MOISTURE DECREASING TOP DOWN ON FRIDAY BUT
SOME MOISTURE REMAINS TRAPPED UNDER THE INVERSION. WE DO EXPECT
MUCH OF THE CLOUDS TO DIMINISH THROUGH THE DAY LINGERING LONGEST
AT KHYR.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 27 10 23 15 / 10 0 0 0
INL 25 0 19 15 / 0 0 0 10
BRD 27 9 22 16 / 0 0 0 0
HYR 31 13 25 15 / 20 0 0 0
ASX 31 15 26 17 / 10 0 0 0
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...SMALL CRAFT ADVISORY UNTIL 10 AM CST THIS MORNING FOR LSZ140-141.
&&
$$
SHORT TERM...JJM
LONG TERM...LE
AVIATION...MELDE
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1118 PM CST THU DEC 4 2014
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 251 PM CST THU DEC 4 2014
SOUTHERLY WINDS CONTINUE THIS AFTERNOON AS HIGH PRESSURE PUSHES OFF
TO THE EAST. THE CONCERN IN THE SHORT TERM PERIOD TURNS TO THE UPPER
TROUGH AND ASSOCIATED SURFACE LOW MOVING EAST TO WEST ACROSS THE
CENTRAL CONUS. ALL APPRECIABLE PRECIPITATION FROM THIS SYSTEM WILL
STAY WELL SOUTH OF THE FA AS THE TRUE FORCING WILL SHIFT FROM NEAR
OKLAHOMA THROUGH THE OHIO RIVER VALLEY REGION THROUGH FRIDAY
EVENING. THIS SYSTEM WILL IMPACT OUR REGION TONIGHT THROUGH FRIDAY
WITH WIDESPREAD LOW STRATUS COVER. THE QUESTION BECOMES WHETHER OR
NOT ANY LIGHT PRECIP COULD BE RUNG OUT OF THIS LOW LEVEL MOISTURE.
AN EVALUATION OF RAP AND NAM SOUNDINGS INDICATE THAT LOW LEVEL
SATURATION BELOW 900H WITH A LITTLE LIFT PRESENT...WARRANTS THE
MENTION OF FREEZING DRIZZLE WITH THE POSSIBILITY OF A FEW
SNOWFLAKES. IN TERMS OF THE WESTERN EXTENT OF THE LOW
CLOUDS...CONFIDENCE IS LOW...BUT STICKING WITH A BLEND OF THE NAM
AND RAP GUIDANCE FOR NOW. WITH LITTLE MIXING TOMORROW...AND VERY
MOIST LOW LEVEL PROFILES INDICATE LOW CLOUDS COULD LINGER FOR MOST
OF THE DAY IN EASTERN AREAS. IN TERMS OF TEMPERATURES...SOUTHERLY
WINDS AND A WARMER AIR MASS WILL MAKE FOR SLIGHTLY ABOVE NORMAL
TEMPERATURES...WITH HIGHS EXPECTED IN THE 30S ON FRIDAY.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 251 PM CST THU DEC 4 2014
LONG TERM CONCERNS REMAIN THE MIXED PRECIPITATION THREAT
DEVELOPING SUNDAY AND THEN THE WARMING TREND THROUGH NEXT WEEK.
COOLER HIGH PRESSURE DROPS INTO THE AREA FRIDAY NIGHT AND
SATURDAY. RETURN FLOW DEVELOPS AHEAD OF THE TROUGH THAT REMAINS
OFF SHORE OF THE PACIFIC NORTHWEST. THIS TROUGH MOVES ASHORE FRIDAY
NIGHT AND INTO THE DAKOTAS AND MINNESOTA ON SUNDAY. BUFKIT
PROFILES INDICATE A NICE WARM LAYER ALOFT AS THE WARMER AIR LIFTS
NORTH INTO THE AREA. THE TROUGH DEEPENS AND MOVES INTO THE AREA
SUNDAY AND SUNDAY NIGHT. WE SHOULD SEE A WINTRY MIX OF FREEZING
RAIN/SLEET AND SNOW CHANGING OVER TO SNOW FROM WEST TO EAST
THROUGH SUNDAY. WILL INCLUDE THIS THREAT IN THE GRIDS AT THIS
TIME. STILL A QUESTION HOW FAR EAST THIS WILL OCCUR AS THE VARIOUS
DETERMINISTIC RUNS ARE STILL IN DISAGREEMENT ON HOW DEEP THE TROUGH
DEVELOPS THROUGH SUNDAY. IT APPEARS THE NAM_WRF HAS TRENDED DEEPER
WITH THE TROUGH...MORE DYNAMIC...WHICH MAY PRECLUDE SIGNIFICANT
PERIOD OF MIXED PRECIPITATION. CONTINUED THE HIGH CHANCE POP TREND
FOR NOW. THE THALER QG FROM THE NAM AND THE GFS SHOWS DECENT
FORCING BEING GENERATED AHEAD OF THE TROUGH. IF THIS CONTINUES...WILL
INCREASE POPS IN LATER FORECASTS. THE GFS IS THE WEAKEST...AND
CONTINUES TO MOVE THE SURFACE LOW WELL NORTH OF THE AREA.
COOLER AIR FOLLOWS THIS SYSTEM FOR MONDAY NIGHT AND TUESDAY. THEN
SOME DISCREPANCY IN THE MODELS WITH THE POSSIBILITY OF ANOTHER
TROUGH DROPPING SOUTH AND EAST OVER THE AREA FOR
WEDNESDAY/THURSDAY TIME FRAME. THE ECMWF IS MORE BULLISH ON
DEVELOPING A SYSTEM OVER THE AREA DURING THIS TIME PERIOD. WE
CURRENTLY HAVE A DRY FORECAST FOR THE MID PART OF THE WEEK. BOTH
MODELS SUGGEST THE UPPER RIDGE FINALLY PROPAGATES EAST INTO THE
AREA BY NEXT WEEKEND. THIS SHOULD YIELD MUCH WARMER AIR WITH A
GOOD SNOW MELT ANTICIPATED.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1058 PM CST THU DEC 4 2014
STRATUS IS NOW FIRMLY IN PLACE ACROSS EASTERN MN AND WESTERN WI
THIS EVENING...AND WE DON`T EXPECT THE MVFR CEILINGS TO DISSIPATE
FOR AT LEAST THE NEXT 12-18 HOURS. KSTC WILL REMAIN ON THE WESTERN
EDGE AND HAS THE MOST UNCERTAINTY. IN FACT...WE DO EXPECT SLIGHT
LOWERING OF CLOUD BASES WITH TIME IN THE EARLY MORNING HOURS.
OTHERWISE...WE EXPECT LITTLE TO NO PRECIP WITH THE CLOUDS TONIGHT
OR TOMORROW.
KMSP...
WE`LL NEED TO KEEP A CLOSE EYE ON THE LOW STUFF TONIGHT AND
WHETHER CLOUDS BASES WILL BE LOW ENOUGH TO IMPACT THE MORNING
RUSH. WE TYPICALLY SEE LOWERING TO NEAR OR BELOW 1000FT IN THESE
SITUATIONS IN WINTER...SO THAT`S WHAT WE`RE SHOOTING FOR IN THE
LATEST TAF. NOT A CERTAINTY WE GET IFR CEILINGS...BUT MORE OFTEN
THAN NOT WE DO ON NIGHTS LIKE THIS.
/OUTLOOK FOR KMSP/
SAT...VFR. WINDS E/NE AT 5-10 KTS.
SUN...VFR WITH MVFR/-SN/-RA/-PL POSSIBLE. WINDS S AT 10G20KTS.
MON...VFR. POSSIBLE MVFR CIGS EARLY. WINDS WNW/NW 10-15 KTS.
&&
$$
SHORT TERM...SPD
LONG TERM...DWE
AVIATION...CLF
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
935 PM CST Sat Dec 6 2014
.UPDATE:
Issued at 918 PM CST Sat Dec 6 2014
Primary meteorological elements of interest tonight are sky cover
and temperatures. Complicated sky cover forecast as 11-3.9 micron
channel is showing advection of the low stratus deck slowly to the
WSW at around 15-20 knots. Concurrently...some thick cirrus is
moving ahead of the next shortwave and spilling over midlevel
ridge axis. Have updated grids to decrease the sky cover in the
near term where stratus deck is moving out of before ramping
opaque cloud cover back up due to the aforementioned thick cirrus
shield.
Other problem tonight as been temperatures as they have cooled off
quickly in areas which have scattered out due to loss of low
stratus deck. As a result...lowered temps in northeast Missouri
and southwest Illinois a bit through 6-9Z before leveling off as
cirrus overtakes the same region. Net result...not too much change
from previous forecast`s overnight minimums.
Gosselin
&&
.SHORT TERM: (Through Late Tonight)
Issued at 300 PM CST Sat Dec 6 2014
Low stratus located within the southern portion of a large high
pressure system continues to dominate the region at mid afternoon.
There has been a slow clearing trend to our north with the clearing
line located near the MO/IA border into northern IL. This high
pressure system will dominate tonight as it moves to the east with
low level flow gradually veering to easterly by mid evening and
then east-southeasterly overnight. Given the trends in the wind
field, there will probably be additional southward clearing into
the early evening then the northern edge will hold steady before
retreating back northwest overnight. The RAP H950 RH is the only
guidance that seems to have a decent handle on this evolution. The
abundance of clouds tonight would suggest MOS guidance is too low
on mins, with the coolest values expected across northeast MO and
west central IL.
Glass
.LONG TERM: (Sunday through Next Saturday)
Issued at 300 PM CST Sat Dec 6 2014
The high pressure system will continue to retreat on Sunday and
this will keep low clouds prevalent. Add in high clouds and it will
make for a mostly cloudy-cloudy day. There are some indications that
southern portions of the CWA could see some clearing from the
south of the low clouds, and hence warmer high temps are expected.
The next threat of precipitation will come Sunday night into
Monday morning. A short wave trof will dig into the mid-upper MS
valley. The large scale ascent associated with this wave along
increasing mid level moisture and low level warm advection should
be sufficient to generate some spotty/scattered precipitation
ahead of the attendant cold front. Temperature profiles indicate
the precipitation should be in the form of rain, with the highest
pops late Monday night across northeast MO and along and east of
the MS River on Monday morning. Monday should be milder with
decreasing clouds as first a prefrontal trof and then the cold
front then sweeps through the area. Another brief round of cold
air then dominates on Tuesday with expansive high pressure.
The upper air pattern will be in transition during the extended
period from Wednesday into next weekend. The eastern U.S. upper
trof/low will be progressive lifting northeast and eventually off
the Atlantic Seaboard. A northwest flow short wave in the wake of
the slowly retreating trof looks to impact our area sometime late
Wednesday into early Thursday, however present indications are any
precipitation threat should be confined to western MO. Heights
aloft then gradually rise in the wake of the shortwave trof and
high pressure departs, leading to southerly low level flow Friday
into the Saturday and a warming trend.
Glass
&&
.AVIATION: (For the 00z TAFs through 00z Sunday Evening)
Issued at 550 PM CST Sat Dec 6 2014
IFR and low end MVFR ceilings will continue to prevail across the
entire area tonight...except for parts of northeast Missouri and
west central Illinois where it will briefly clear out this
evening. Expect that where ceilings have risen to MVFR, we will
see a slow falling of ceilings during the late evening and
overnight. Additionally, expect the clouds to redevelop overnight
where it clears out this evening. Think pretty much all areas
should be back down to IFR by 08-10Z Sunday morning. All guidance
is showing improving conditions during the late morning and early
afternoon, eventually scattering out the low clouds sometime after
19-20Z across much of the area. VFR ceilings AOA 10,000 FT will
likely persist though as an upper level disturbance approaches the
area from the west.
Specifics for KSTL:
While ceilings have risen to MVFR in the past couple of hours,
expect cooling night time temperatures to eventually bring ceilings
back down below 1,000FT sometime around midnight. Not really sure
when that will be, but most guidance points to between 06-07Z time
frame. IFR ceilings should persist through much of Sunday morning
with ceilings rising toward afternoon. Low ceilings are expected
to scatter out Sunday afternoon...again timing is uncertain but it
does look promising for scattering during the afternoon. Higher
clouds AOA 10,000FT will prevail after that as an upper level
system moves into Missouri from the Plains.
Carney
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
606 PM CST Sat Dec 6 2014
.SHORT TERM: (Through Late Tonight)
Issued at 300 PM CST Sat Dec 6 2014
Low stratus located within the southern portion of a large high
pressure system continues to dominate the region at mid afternoon.
There has been a slow clearing trend to our north with the clearing
line located near the MO/IA border into northern IL. This high
pressure system will dominate tonight as it moves to the east with
low level flow gradually veering to easterly by mid evening and
then east-southeasterly overnight. Given the trends in the wind
field, there will probably be additional southward clearing into
the early evening then the northern edge will hold steady before
retreating back northwest overnight. The RAP H950 RH is the only
guidance that seems to have a decent handle on this evolution. The
abundance of clouds tonight would suggest MOS guidance is too low
on mins, with the coolest values expected across northeast MO and
west central IL.
Glass
.LONG TERM: (Sunday through Next Saturday)
Issued at 300 PM CST Sat Dec 6 2014
The high pressure system will continue to retreat on Sunday and
this will keep low clouds prevalent. Add in high clouds and it will
make for a mostly cloudy-cloudy day. There are some indications that
southern portions of the CWA could see some clearing from the
south of the low clouds, and hence warmer high temps are expected.
The next threat of precipitation will come Sunday night into
Monday morning. A short wave trof will dig into the mid-upper MS
valley. The large scale ascent associated with this wave along
increasing mid level moisture and low level warm advection should
be sufficient to generate some spotty/scattered precipitation
ahead of the attendant cold front. Temperature profiles indicate
the precipitation should be in the form of rain, with the highest
pops late Monday night across northeast MO and along and east of
the MS River on Monday morning. Monday should be milder with
decreasing clouds as first a prefrontal trof and then the cold
front then sweeps through the area. Another brief round of cold
air then dominates on Tuesday with expansive high pressure.
The upper air pattern will be in transition during the extended
period from Wednesday into next weekend. The eastern U.S. upper
trof/low will be progressive lifting northeast and eventually off
the Atlantic Seaboard. A northwest flow short wave in the wake of
the slowly retreating trof looks to impact our area sometime late
Wednesday into early Thursday, however present indications are any
precipitation threat should be confined to western MO. Heights
aloft then gradually rise in the wake of the shortwave trof and
high pressure departs, leading to southerly low level flow Friday
into the Saturday and a warming trend.
Glass
&&
.AVIATION: (For the 00z TAFs through 00z Sunday Evening)
Issued at 550 PM CST Sat Dec 6 2014
IFR and low end MVFR ceilings will continue to prevail across the
entire area tonight...except for parts of northeast Missouri and
west central Illinois where it will briefly clear out this
evening. Expect that where ceilings have risen to MVFR, we will
see a slow falling of ceilings during the late evening and
overnight. Additionally, expect the clouds to redevelop overnight
where it clears out this evening. Think pretty much all areas
should be back down to IFR by 08-10Z Sunday morning. All guidance
is showing improving conditions during the late morning and early
afternoon, eventually scattering out the low clouds sometime after
19-20Z across much of the area. VFR ceilings AOA 10,000 FT will
likely persist though as an upper level disturbance approaches the
area from the west.
Specifics for KSTL:
While ceilings have risen to MVFR in the past couple of hours,
expect cooling night time temperatures to eventually bring ceilings
back down below 1,000FT sometime around midnight. Not really sure
when that will be, but most guidance points to between 06-07Z time
frame. IFR ceilings should persist through much of Sunday morning
with ceilings rising toward afternoon. Low ceilings are expected
to scatter out Sunday afternoon...again timing is uncertain but it
does look promising for scattering during the afternoon. Higher
clouds AOA 10,000FT will prevail after that as an upper level
system moves into Missouri from the Plains.
Carney
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
322 PM CST FRI DEC 5 2014
.SYNOPSIS...
ISSUED AT 322 PM CST FRI DEC 5 2014
WEAK COLD FRONT STALLING NEAR THE KS/NEB BORDER THIS AFTERNOON.
MOSTLY SUNNY SKIES AND SOME 10 TO 15 MPH NORTHERLY WINDS BEHIND THE
FRONT HAVE ALLOWED FOR GOOD MIXING WITH TEMPERATURES IN THE UPPER
40S AND 50S. MEANWHILE HIGH PRESSURE IS SETTLING ACROSS THE NORTHERN
PLAINS.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 322 PM CST FRI DEC 5 2014
TONIGHT HIGH PRESSURE WILL CONTINUE TO DRIFT ACROSS THE NORTHERN
PLAINS. THIS WILL CAUSE THE WINDS TO BECOME EASTERLY/SOUTHEASTERLY.
THIS WIND SWITCH WILL HELP TO USHER IN SOME LL MOISTURE. THIS WILL
COMBINE WITH MOSTLY CLEAR SKIES AND GOOD RADIATIONAL COOLING TO
PRODUCE LOWS IN THE TEENS AND MAYBE SOME PATCHY FOG. SOME CONCERNS
TOWARDS THE FOG DEVELOPMENT AS AFTERNOON TEMPS IN THE 50S MIXED THE
MOISTURE FAIRLY WELL. ALSO A VERY DRY SURFACE...LITTLE RAIN OVER THE
LAST MONTH ACROSS MOST OF THE AREA. THE NAM IS THE ONLY MODEL
SUGGESTING DEVELOPMENT...ALTHOUGH IT IS A LITTLE HIGH WITH CURRENT
DEW PTS. THE RUC IS LESS FAVORABLE...BUT IS CLOSER BUT IS A DEGREE
OR SO TO LOW WITH DEW PTS. THUS THE FORECAST DOES INCLUDE SOME
PATCHY FOG IN THE PLATTE RIVER VALLEY...WHICH IS LIKELY THE FIRST
PLACE FOR DEVELOPMENT ALTHOUGH CONFIDENCE IS LOW. HAVE ALSO INCLUDED
SOME FOG ACROSS THE FAR NORTHWEST...HOWEVER THERE IS BETTER GROUND
MOISTURE.
TOMORROW COOL HIGH PRESSURE CENTERED OVER MINNESOTA...HOWEVER WILL
SEE SOME COOLER TEMPS ALOFT /850 MB TEMPS AROUND 5C/ INTO THE HIGH
PLAINS. WILL KEEP TEMPS ABOUT 5 TO 10 DEGREES COOLER THAN TODAY.
LATELY THE WARMER MAV HAS BEEN CLOSER TO REALITY AND FAVORED THESE
WARMER NUMBERS FOR TOMORROW.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 322 PM CST FRI DEC 5 2014
...ABOVE NORMAL TEMPERATURES AND DRY CONDITIONS FORECAST SUNDAY
THROUGH FRIDAY...
MID RANGE PERIODS (SATURDAY NIGHT THROUGH MONDAY)...
THE UPPER TROUGH EXITING THE ROCKIES WILL MOVE ACROSS WESTERN
NEBRASKA SATURDAY NIGHT INTO SUNDAY. WHILE MOISTURE WILL BE AMPLE
FROM H7 TO H5...H85 TO H7 RELATIVELY DRY. CONCERN LIES IN
SATURATED LAYER BELOW 875 MB. WITH WEAK OMEGA PRESENT ALONG WITH
SUPERCOOLED DROPLETS OF -1C TO -3C...INTRODUCED PATCHY FREEZING
FRIZZLE WHICH IS POSSIBLE FROM 09Z TO 15Z SUNDAY. SURFACE
TEMPERATURES DURING THIS TIME SHOULD RANGE FROM 28 TO 32 DEGREES.
THE AREA MAY AFFECT SOUTHEASTERN AREAS MAINLY EAST OF A CURTIS
THROUGH CALLAWAY AND STUART LINE. OTHERWISE CLEARING SKIES FROM
WEST TO EAST ON SUNDAY WITH ANOTHER NICE WARMUP. DOWNSLOPING WEST
TO NORTHWEST WINDS 5 TO 15 MPH SHOULD PUSH HIGHS UP INTO THE LOWER
TO MID 50S...EXCEPT COOLER UPPER 40S NEAR ONEILL AND BARTLETT. A
WEAK COLD FRONT SUNDAY NIGHT. HIGHS MONDAY HOWEVER WILL REMAIN
VERY SIMILAR TO SUNDAY.
EXTENDED PERIODS (MONDAY NIGHT THROUGH FRIDAY)...
THE MILD CONDITIONS WILL PERSIST IN THE EXTENDED PERIODS AS UPPER
RIDGING DOMINATES THE CENTRAL CONUS. INCREASED TROUGHING ONTO THE
WEST COAST WILL ALSO HELP TO AMPLIFY DOWNSTREAM RIDGE.
UPPER RIDGING WILL BUILD INTO THE CENTRAL CONUS WEDNESDAY THROUGH
FRIDAY WITH HIGHS IN THE 50S. SOME HIGHS IN THE WEST COULD EXCEED
60 DEGREES WEDNESDAY AND BEYOND. BY FRIDAY...A STRONG UPPER
TROUGH WILL MOVE ONTO THE WEST COAST.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1142 AM CST FRI DEC 5 2014
LITTLE CONCERNS FOR AVIATION THE NEXT 24 HOURS. NORTHERLY WINDS
THIS AFTERNOON AROUND 10 TO 15 KTS WILL BECOME LIGHT AND VARIABLE
OVERNIGHT. A SWITCH TO LIGHT SOUTHERLY WINDS IS EXPECTED TOMORROW
MORNING. ALSO EXPECT CIGS ABOVE 10K FT AND DRY CONDITIONS.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...MASEK
SHORT TERM...MASEK
LONG TERM...ROBERG
AVIATION...MASEK
AREA FORECAST DISCUSSION
NWS HASTINGS NE
218 PM CST FRI DEC 5 2014
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 218 PM CST FRI DEC 5 2014
THE SHORT TERM FORECAST THROUGH SATURDAY IS RELATIVELY QUIET IN
TERMS OF MAJOR WEATHER ISSUES. MILD TEMPERATURES THIS AFTERNOON
WILL BE TEMPERED A BIT IN THE WAKE OF FRONTAL BOUNDARY PASSING
THROUGH THE FORECAST AREA AT THIS TIME. TEMPERATURES WILL ACTUALLY
BE NEAR NORMAL TONIGHT AND SATURDAY...THOUGH IT WILL FEEL QUITE A
BIT COOLER TONIGHT WITH UPPER TEENS AND 20S. DECENT MODEL AGREEMENT
WITH SOME LOWER CLOUDS TRYING TO SNEAK BACK WEST TONIGHT AND PUSH
INTO THE HIGHWAY 81 CORRIDOR AREA TOWARD DAWN SATURDAY AND LINGER
INTO THE MORNING. HAVE INCREASED CLOUDS IN THAT AREA...AND ADDED A
BIT OF PATCHY FOG FOG WHICH ALIGNS WELL WITH WFOS OMAHA AND TOPEKA
FORECAST. SOME CONCERN OF FOG IN THE NORTHWEST PART OF THE FORECAST
AREA...WHERE WINDS TURN NEARLY CALM. HRRR HINTS AT LOWER CLOUDS AND
VISIBILITY OVER PARTS OF THE SANDHILLS. WILL HOLD OFF FOR NOW BUT
WORTH NOTING HEADING INTO TONIGHT. BEYOND THAT...SATURDAY WILL SEE
MID/HIGH CLOUDS START TO INCREASE FROM THE WEST IN THE AFTERNOON AS
WARM ADVECTION INCREASES AHEAD OF NEXT WEATHER SYSTEM ON SUNDAY.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 218 PM CST FRI DEC 5 2014
GUIDANCE SUGGESTS THE LONG-TERM FORECAST PERIOD WILL START OFF WITH
UPPER TROPOSPHERIC RIDGING OVER THE CENTRAL CONUS AND A SUBTLE
TROUGH AXIS JUST WEST OF THE ROCKY MOUNTAINS AT 00Z SUNDAY. THIS
TROUGH AXIS IS EXPECTED TO SHIFT EAST SATURDAY NIGHT INTO
SUNDAY...WITH THIS TROUGH AXIS LIKELY CLEARING OUR AREA DURING THE
DAY SUNDAY. NORTHWESTERLY UPPER TROPOSPHERIC FLOW IS THEN EXPECTED
TO OVERTAKE THE CENTRAL CONUS THROUGH MUCH OF THE REMAINDER OF THE
LONG-TERM FORECAST PERIOD AS UPPER TROPOSPHERIC TROUGHING
STRENGTHENS OVER THE EASTERN CONUS AND RIDGING BUILDS ACROSS THE
WEST.
ALTHOUGH UNCERTAINTY REMAINS...THERE REMAIN HINTS AT A BRIEF PERIOD
OF PRECIPITATION PRODUCTION ACROSS THE CENTRAL PLAINS ON SUNDAY AS
TROPOSPHERIC MOISTURE AND UPPER TROPOSPHERIC THERMAL ADVECTION
INCREASES AHEAD OF THE APPROACHING TROUGH AXIS. QPF FIELDS FROM THE
NAM...OPERATIONAL GFS...EC AND SREF-MEAN ALL CONTINUE TO SUGGEST
LIGHT PRECIPITATION WILL BE REALIZED ACROSS PORTIONS OF OUR CWA ON
SUNDAY AND AS A RESULT...CONTINUED WITH POPS...ALBEIT LOW...ACROSS
MUCH OF THE AREA ON SUNDAY. UNFORTUNATELY PRECIPITATION TYPE REMAINS
QUESTIONABLE AS FORECAST PROXIMITY SOUNDINGS FROM ACROSS THE
CWA...PER THE NAM AND OPERATIONAL GFS...SUGGEST AN ELEVATED WARM
LAYER WILL LIKELY PROVIDE LIQUID PRECIPITATION WHILE SURFACE
TEMPERATURE READINGS FALL TO NEAR OR BELOW FREEZING AROUND DAYBREAK
SUNDAY. PREVIOUS SHIFT WENT AHEAD AND INSERTED A MENTION OF LIGHT
FREEZING RAIN FOR A TIME SUNDAY MORNING AND AT THIS TIME...SEE NO
REASON TO REMOVE THIS WORDING. GIVEN ALL THIS...A SLIGHT CHANCE FOR
LIGHT FREEZING RAIN REMAINS IN THE FORECAST FOR MUCH OF THE AREA FOR
A FEW HOURS SUNDAY MORNING AROUND DAYBREAK...WITH LIGHT RAIN THEN
FORECAST BY 14Z AS SURFACE TEMPERATURE READINGS CLIMB ABOVE FREEZING.
THERE MAY ALSO BE A PERIOD OF LIGHT DRIZZLE OR LIGHT FREEZING
DRIZZLE ACROSS PORTIONS OF THE CWA SUNDAY MORNING...WITH GUIDANCE
SUGGESTING 0-1KM RELATIVE HUMIDITY VALUES NEAR 100% WILL ACCOMPANY 0-
1KM BULK SHEAR VALUES OF 25-30KTS. GIVEN THE POTENTIAL FOR A
SATURATED LOWER TROPOSPHERE AS WELL AS SUFFICIENT TURBULENT
MIXING...OPTED TO KEEP A MENTION OF LIGHT DRIZZLE AND LIGHT FREEZING
DRIZZLE GOING IN THE FORECAST FOR SUNDAY MORNING.
AN OVERALL LACK IN OMEGA SHOULD THEN KEEP US DRY THROUGH MUCH OF THE
REST OF THE LONG-TERM FORECAST PERIOD...ALTHOUGH THERE ARE HINTS OF
AN UPPER TROPOSPHERIC SHORT WAVE PERHAPS BRINGING A ROUND OF LIGHT
PRECIPITATION TO THE REGION ON FRIDAY AND AS A RESULT...WENT WITH A
LOW POP ACROSS PORTIONS OF THE CWA ON FRIDAY.
LITTLE IF ANY CHANGE IN BOUNDARY-LAYER AIR MASS SHOULD PRESENT
SIMILAR TEMPERATURE READINGS FROM DAY TO DAY DURING THE LONG-TERM
FORECAST PERIOD...WITH HIGHS IN THE UPPER 40S TO MID 50S AND LOW IN
THE UPPER 20S TO LOWER 30S CURRENTLY FORECAST FOR THE MOST PART.
&&
.AVIATION...(FOR THE 18Z KGRI/KEAR TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1149 AM CST FRI DEC 5 2014
VFR CONDITIONS ARE FORECAST THROUGH THE PERIOD. WINDS WILL TAKE ON
NORTHERNLY SLANT THIS AFTERNOON BEHIND A COLD FRONT...AND
GRADUALLY START A TURN NORTHEAST SATURDAY MORNING. NO VISIBILITY
RESTRICTS ARE FORECAST AT THIS TIME...AND ONLY PASSING HIGH CLOUDS
ARE EXPECTED.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...NOAA/NWS/MORITZ
LONG TERM...BRYANT
AVIATION...NOAA/NWS/MORITZ
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1151 AM CST FRI DEC 5 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 326 AM CST FRI DEC 5 2014
AN UPPER LOW PRESSURE SYSTEM WAS TRACKING ACROSS KS EARLY THIS
MORNING WHICH HAS PRODUCED WIDESPREAD RAINFALL ACROSS THE SOUTHERN
TWO THIRDS OF KS. THE AREA OF RAIN HAS GRADUALLY BEEN MOVING NORTHEAST
INTO NORTHEAST KS AS THE UPPER SYSTEM LIFTS OUT...WITH OUR
SOUTHERN CWA ON THE NORTHERN EDGE OF THE PRECIPITATION. RAINFALL
WILL REMAIN POSSIBLE UNTIL AROUND DAYBREAK...WITH THE PCPN MOVING
OUT SHORTLY THEREAFTER BEHIND THE TROUGH AXIS.
ALSO A CONCERN FOR THIS MORNING IS THE POTENTIAL FOR FOG
DEVELOPMENT DUE TO THE INCREASE IN LLVL MOISTURE...AND AS WINDS
BECOME LIGHT/VARIABLE ALONG THE SFC TROUGH AND AHEAD OF AN
APPROACHING COLD FRONTAL BOUNDARY. SO FAR THE RAP SEEMS TO HAVE
THE BEST HANDLE ON THE POTENTIAL FOR THIS...KEEPING THE LOWEST
VSBYS ALONG THE MISSOURI RIVER...WHEREAS THE NAM SUGGEST FOG MAY
REACH AS FAR WEST AS THE EASTERN HALF OF OUR CWA. SO FAR THE
LOWEST VSBYS ARE IN THE 3 TO 5 MILE RANGE AND MORE SO ASSOCIATED
WITH THE PCPN IN OUR SOUTHERN ZONES.
A SURFACE TROUGH/COOL FRONT CROSSES THE PLAINS DURING THE
DAY...SWITCHING WINDS NORTHERLY AND SCOURS THE LLVL MOISTURE TO
THE EAST. COOLER AIR IS SLOW TO ADVECT SOUTH AND WE ARE STILL
LOOKING FOR RATHER MILD HIGHS IN THE 40S/50S THIS AFTN AIDED BY
OUR WARM START. A COLDER AIRMASS SETTLES SOUTH OVERNIGHT AS A
STRONG HIGH PRESSURE SYSTEM BUILDS SOUTH AND EAST FM THE DAKOTAS.
IN THE COOLER/DRIER AIRMASS...LOWS ARE EXPECTED TO AVERAGE IN THE
TEENS/20S. MODELS SUGGEST THAT LOW CLOUD COVER WILL BE ON THE
PERIPHERY OF OUR SOUTHEAST CWA AND NAM/MET GUIDANCE INDICATES
POTENTIAL FOR FOG ON THE EDGE OF LOW CLOUDS TOWARD THE KRSL AREA.
SREF VSBY PROGS KEEP FOG POTENTIAL FARTHER EAST AND WITH NORTHERLY
WIND COMPONENT...HAVE LEFT FOG OUT OF FORECAST.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 326 AM CST FRI DEC 5 2014
PRIMARY FORECAST CONCERN THROUGH THE LONG TERM LIES MAINLY WITH LATE
WEEKEND PRECIPITATION CHANCES.
EXPECTING DRY CONDITIONS TO START OFF THE PERIOD ON SATURDAY...WITH
MODELS IN GOOD AGREEMENT SHOWING THE AREA UNDER THE INFLUENCE OF
UPPER LEVEL SHORTWAVE RIDGING SLIDING EAST...SET UP BETWEEN A
DISTURBANCE MAKING ITS WAY THROUGH THE MIDWEST...AND ANOTHER WORKING
THROUGH THE 4 CORNERS REGION AND ROCKIES. AT THE SURFACE...EXPECTING
THE CWA TO BE SITTING UNDER A RIDGE AXIS...EXTENDING FROM THE PARENT
HIGH LOCATED OVER NRN MN. BRINGING LIGHTER NRLY WINDS TO START THE
DAY...WINDS WILL GRADUALLY BECOME MORE EASTERLY THROUGH THE MORNING
HOURS...THEN SOUTHEASTERLY BY LATE AFTERNOON AS THAT HIGH/RIDGE AXIS
PUSHES EAST OF THE CWA. SITTING UNDER A COOLER AIRMASS...FORECAST
HIGHS CURRENTLY RANGE FROM THE UPPER 30S IN THE NORTHEAST TO THE
LOWER/MID 40S OVER THE WEST.
GREATER UNCERTAINTY IN THE FORECAST ARRIVES AS WE GET INTO THE LATE
OVERNIGHT HOURS SATURDAY NIGHT INTO SUNDAY...AS THAT ABOVE MENTIONED
UPPER LEVEL DISTURBANCE EMERGES OUT OF THE ROCKIES AND ONTO THE
PLAINS. EXPECTING CONDITIONS PRIOR TO MIDNIGHT TO REMAIN DRY...BUT
MODELS SHOW INCREASING LOWER LEVEL MOISTURE WITH TIME
/THOUGH NOT SIGNIFICANTLY/...THANKS TO MORE SOUTHERLY SFC/LL WINDS.
FORECAST SOUNDINGS REFLECT THAT...SHOWING THE LOWEST LAYERS BECOMING
SATURATED WITH TIME...WITH LIFT PICKING UP AS THAT UPPER LEVEL
DISTURBANCE INCHES CLOSER. CONCERNED ABOUT PRECIPITATION DEVELOPING
ACROSS PORTIONS OF THE CWA...HAD INHERITED A MENTION IN THE PRE DAWN
HOURS SUNDAY AND DECIDED TO KEEP IT GOING. DECIDED TO GO WITH A DZ
MENTION WITH THERE BEING A DRIER LAYER IN PLACE ABOVE THAT LOWER
LEVEL SATURATION. AS MENTIONED...CONFIDENCE IS NOT HIGH IN ITS
OCCURRENCE...BUT CANT COMPLETELY RULE IT OUT EITHER. HAVE SOME LOW
POPS GOING AFTER 12Z...AS THE LIFT CONTINUES TO INCREASE AS THE WAVE
PASSES...THINKING THAT DURING THE AFTERNOON HOURS THE BETTER CHANCES
WILL SHIFT EAST OF THE CWA...SO ONLY HAVE THE FAR EAST WITH SOME
LINGERING POPS. THE MAIN QUESTION WITH THE EARLY MORNING
PRECIPITATION IS WHERE WILL TEMPERATURES END UP. THOUGHTS ARE THAT
TEMPS WILL LEVEL OFF /PERHAPS RISE A FEW DEGREES/ ONCE THE THICKER
CLOUD COVER/BETTER MOISTURE MOVES IN...BUT WITH THE POTENTIAL FOR
TEMPS TO BE HOVERING AROUND THAT FREEZING MARK SHOULD THE PRECIP
DEVELOP...FELT A LIGHT FZDZ/FZRA MENTION SHOULD BE INCLUDED WITH THE
LIQUID MENTION. AT THIS POINT...SHOULD FREEZING PRECIP OCCUR...IT IS
NOT EXPECTED TO CAUSE NOTABLE PROBLEMS...AS IT WOULD BE LIGHT...AND
SHORT LIVED WITH TEMPS INCREASING AFTER SUNRISE. WITH THIS BEING IN
THE 4TH PERIOD...STILL SOME TIME TO ADJUST BASED ON HOW MODELS
TREND. OTHERWISE FOR SUNDAY...SHOULD BE PLENTY OF CLOUD COVER
AROUND...ESP IN THE EAST...BUT EXPECTING A REBOUND IN TEMPS...WITH
HIGHS RANGING FROM THE MID 40S EAST TO LOWER 50S WEST.
LOOKING AHEAD TO THE UPCOMING WORK WEEK MONDAY THROUGH THURSDAY...NO
SIGNIFICANT CHANGES WERE MADE TO THE FORECAST. IT REMAINS DRY AT
THIS POINT...WITH MODELS GENERALLY IN GOOD AGREEMENT SHOWING A LACK
OF NOTABLE SYSTEMS MOVING THROUGH GENERALLY NORTHWESTERLY FLOW IN
THE UPPER LEVELS...THOUGH WEAKER DISTURBANCES MOVING THROUGH IS A
POSSIBILITY. JUST TOO MUCH UNCERTAINTY AT THIS POINT TO INSERT ANY
PRECIP MENTION. NOT EXPECTING ANY BIG SWINGS IN TEMPERATURES THROUGH
THIS TIME FRAME...SHOULD SEE A BIT OF A WARMING TREND...WITH HIGHS
FOR WED/THUR BACK IN THE MID 50S FOR MOST OF THE CWA.
&&
.AVIATION...(FOR THE 18Z KGRI/KEAR TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1149 AM CST FRI DEC 5 2014
VFR CONDITIONS ARE FORECAST THROUGH THE PERIOD. WINDS WILL TAKE ON
NORTHERNLY SLANT THIS AFTERNOON BEHIND A COLD FRONT...AND
GRADUALLY START A TURN NORTHEAST SATURDAY MORNING. NO VISIBILITY
RESTRICTS ARE FORECAST AT THIS TIME...AND ONLY PASSING HIGH CLOUDS
ARE EXPECTED.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...FAY
LONG TERM...ADP
AVIATION...MORITZ
AREA FORECAST DISCUSSION
NWS HASTINGS NE
515 AM CST FRI DEC 5 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 326 AM CST FRI DEC 5 2014
AN UPPER LOW PRESSURE SYSTEM WAS TRACKING ACROSS KS EARLY THIS
MORNING WHICH HAS PRODUCED WIDESPREAD RAINFALL ACROSS THE SOUTHERN
TWO THIRDS OF KS. THE AREA OF RAIN HAS GRADUALLY BEEN MOVING NORTHEAST
INTO NORTHEAST KS AS THE UPPER SYSTEM LIFTS OUT...WITH OUR
SOUTHERN CWA ON THE NORTHERN EDGE OF THE PRECIPITATION. RAINFALL
WILL REMAIN POSSIBLE UNTIL AROUND DAYBREAK...WITH THE PCPN MOVING
OUT SHORTLY THEREAFTER BEHIND THE TROUGH AXIS.
ALSO A CONCERN FOR THIS MORNING IS THE POTENTIAL FOR FOG
DEVELOPMENT DUE TO THE INCREASE IN LLVL MOISTURE...AND AS WINDS
BECOME LIGHT/VARIABLE ALONG THE SFC TROUGH AND AHEAD OF AN
APPROACHING COLD FRONTAL BOUNDARY. SO FAR THE RAP SEEMS TO HAVE
THE BEST HANDLE ON THE POTENTIAL FOR THIS...KEEPING THE LOWEST
VSBYS ALONG THE MISSOURI RIVER...WHEREAS THE NAM SUGGEST FOG MAY
REACH AS FAR WEST AS THE EASTERN HALF OF OUR CWA. SO FAR THE
LOWEST VSBYS ARE IN THE 3 TO 5 MILE RANGE AND MORE SO ASSOCIATED
WITH THE PCPN IN OUR SOUTHERN ZONES.
A SURFACE TROUGH/COOL FRONT CROSSES THE PLAINS DURING THE
DAY...SWITCHING WINDS NORTHERLY AND SCOURS THE LLVL MOISTURE TO
THE EAST. COOLER AIR IS SLOW TO ADVECT SOUTH AND WE ARE STILL
LOOKING FOR RATHER MILD HIGHS IN THE 40S/50S THIS AFTN AIDED BY
OUR WARM START. A COLDER AIRMASS SETTLES SOUTH OVERNIGHT AS A
STRONG HIGH PRESSURE SYSTEM BUILDS SOUTH AND EAST FM THE DAKOTAS.
IN THE COOLER/DRIER AIRMASS...LOWS ARE EXPECTED TO AVERAGE IN THE
TEENS/20S. MODELS SUGGEST THAT LOW CLOUD COVER WILL BE ON THE
PERIPHERY OF OUR SOUTHEAST CWA AND NAM/MET GUIDANCE INDICATES
POTENTIAL FOR FOG ON THE EDGE OF LOW CLOUDS TOWARD THE KRSL AREA.
SREF VSBY PROGS KEEP FOG POTENTIAL FARTHER EAST AND WITH NORTHERLY
WIND COMPONENT...HAVE LEFT FOG OUT OF FORECAST.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 326 AM CST FRI DEC 5 2014
PRIMARY FORECAST CONCERN THROUGH THE LONG TERM LIES MAINLY WITH LATE
WEEKEND PRECIPITATION CHANCES.
EXPECTING DRY CONDITIONS TO START OFF THE PERIOD ON SATURDAY...WITH
MODELS IN GOOD AGREEMENT SHOWING THE AREA UNDER THE INFLUENCE OF
UPPER LEVEL SHORTWAVE RIDGING SLIDING EAST...SET UP BETWEEN A
DISTURBANCE MAKING ITS WAY THROUGH THE MIDWEST...AND ANOTHER WORKING
THROUGH THE 4 CORNERS REGION AND ROCKIES. AT THE SURFACE...EXPECTING
THE CWA TO BE SITTING UNDER A RIDGE AXIS...EXTENDING FROM THE PARENT
HIGH LOCATED OVER NRN MN. BRINGING LIGHTER NRLY WINDS TO START THE
DAY...WINDS WILL GRADUALLY BECOME MORE EASTERLY THROUGH THE MORNING
HOURS...THEN SOUTHEASTERLY BY LATE AFTERNOON AS THAT HIGH/RIDGE AXIS
PUSHES EAST OF THE CWA. SITTING UNDER A COOLER AIRMASS...FORECAST
HIGHS CURRENTLY RANGE FROM THE UPPER 30S IN THE NORTHEAST TO THE
LOWER/MID 40S OVER THE WEST.
GREATER UNCERTAINTY IN THE FORECAST ARRIVES AS WE GET INTO THE LATE
OVERNIGHT HOURS SATURDAY NIGHT INTO SUNDAY...AS THAT ABOVE MENTIONED
UPPER LEVEL DISTURBANCE EMERGES OUT OF THE ROCKIES AND ONTO THE
PLAINS. EXPECTING CONDITIONS PRIOR TO MIDNIGHT TO REMAIN DRY...BUT
MODELS SHOW INCREASING LOWER LEVEL MOISTURE WITH TIME
/THOUGH NOT SIGNIFICANTLY/...THANKS TO MORE SOUTHERLY SFC/LL WINDS.
FORECAST SOUNDINGS REFLECT THAT...SHOWING THE LOWEST LAYERS BECOMING
SATURATED WITH TIME...WITH LIFT PICKING UP AS THAT UPPER LEVEL
DISTURBANCE INCHES CLOSER. CONCERNED ABOUT PRECIPITATION DEVELOPING
ACROSS PORTIONS OF THE CWA...HAD INHERITED A MENTION IN THE PRE DAWN
HOURS SUNDAY AND DECIDED TO KEEP IT GOING. DECIDED TO GO WITH A DZ
MENTION WITH THERE BEING A DRIER LAYER IN PLACE ABOVE THAT LOWER
LEVEL SATURATION. AS MENTIONED...CONFIDENCE IS NOT HIGH IN ITS
OCCURRENCE...BUT CANT COMPLETELY RULE IT OUT EITHER. HAVE SOME LOW
POPS GOING AFTER 12Z...AS THE LIFT CONTINUES TO INCREASE AS THE WAVE
PASSES...THINKING THAT DURING THE AFTERNOON HOURS THE BETTER CHANCES
WILL SHIFT EAST OF THE CWA...SO ONLY HAVE THE FAR EAST WITH SOME
LINGERING POPS. THE MAIN QUESTION WITH THE EARLY MORNING
PRECIPITATION IS WHERE WILL TEMPERATURES END UP. THOUGHTS ARE THAT
TEMPS WILL LEVEL OFF /PERHAPS RISE A FEW DEGREES/ ONCE THE THICKER
CLOUD COVER/BETTER MOISTURE MOVES IN...BUT WITH THE POTENTIAL FOR
TEMPS TO BE HOVERING AROUND THAT FREEZING MARK SHOULD THE PRECIP
DEVELOP...FELT A LIGHT FZDZ/FZRA MENTION SHOULD BE INCLUDED WITH THE
LIQUID MENTION. AT THIS POINT...SHOULD FREEZING PRECIP OCCUR...IT IS
NOT EXPECTED TO CAUSE NOTABLE PROBLEMS...AS IT WOULD BE LIGHT...AND
SHORT LIVED WITH TEMPS INCREASING AFTER SUNRISE. WITH THIS BEING IN
THE 4TH PERIOD...STILL SOME TIME TO ADJUST BASED ON HOW MODELS
TREND. OTHERWISE FOR SUNDAY...SHOULD BE PLENTY OF CLOUD COVER
AROUND...ESP IN THE EAST...BUT EXPECTING A REBOUND IN TEMPS...WITH
HIGHS RANGING FROM THE MID 40S EAST TO LOWER 50S WEST.
LOOKING AHEAD TO THE UPCOMING WORK WEEK MONDAY THROUGH THURSDAY...NO
SIGNIFICANT CHANGES WERE MADE TO THE FORECAST. IT REMAINS DRY AT
THIS POINT...WITH MODELS GENERALLY IN GOOD AGREEMENT SHOWING A LACK
OF NOTABLE SYSTEMS MOVING THROUGH GENERALLY NORTHWESTERLY FLOW IN
THE UPPER LEVELS...THOUGH WEAKER DISTURBANCES MOVING THROUGH IS A
POSSIBILITY. JUST TOO MUCH UNCERTAINTY AT THIS POINT TO INSERT ANY
PRECIP MENTION. NOT EXPECTING ANY BIG SWINGS IN TEMPERATURES THROUGH
THIS TIME FRAME...SHOULD SEE A BIT OF A WARMING TREND...WITH HIGHS
FOR WED/THUR BACK IN THE MID 50S FOR MOST OF THE CWA.
&&
.AVIATION...(FOR THE 12Z KGRI/KEAR TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 505 AM CST FRI DEC 5 2014
CLOUD COVER WILL DECREASE DURING THE DAY AS AN UPPER LOW PRESSURE
SYSTEM MOVES EAST INTO MISSOURI. THE PASSAGE OF A SFC TROUGH AND
COLD FRONTAL BOUNDARY WILL SWITCH LIGHT/VARIABLE WINDS TO A
NORTHERLY DIRECTION BEFORE NOON. WINDS WILL REMAIN NORTHERLY
TONIGHT AS SFC RIDGE BUILDS SOUTHEAST ONTO THE PLAINS.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...FAY
LONG TERM...ADP
AVIATION...FAY
AREA FORECAST DISCUSSION
NWS HASTINGS NE
340 AM CST FRI DEC 5 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 326 AM CST FRI DEC 5 2014
AN UPPER LOW PRESSURE SYSTEM WAS TRACKING ACROSS KS EARLY THIS
MORNING WHICH HAS PRODUCED WIDESPREAD RAINFALL ACROSS THE SOUTHERN
TWO THIRDS OF KS. THE AREA OF RAIN HAS GRADUALLY BEEN MOVING NORTHEAST
INTO NORTHEAST KS AS THE UPPER SYSTEM LIFTS OUT...WITH OUR
SOUTHERN CWA ON THE NORTHERN EDGE OF THE PRECIPITATION. RAINFALL
WILL REMAIN POSSIBLE UNTIL AROUND DAYBREAK...WITH THE PCPN MOVING
OUT SHORTLY THEREAFTER BEHIND THE TROUGH AXIS.
ALSO A CONCERN FOR THIS MORNING IS THE POTENTIAL FOR FOG
DEVELOPMENT DUE TO THE INCREASE IN LLVL MOISTURE...AND AS WINDS
BECOME LIGHT/VARIABLE ALONG THE SFC TROUGH AND AHEAD OF AN
APPROACHING COLD FRONTAL BOUNDARY. SO FAR THE RAP SEEMS TO HAVE
THE BEST HANDLE ON THE POTENTIAL FOR THIS...KEEPING THE LOWEST
VSBYS ALONG THE MISSOURI RIVER...WHEREAS THE NAM SUGGEST FOG MAY
REACH AS FAR WEST AS THE EASTERN HALF OF OUR CWA. SO FAR THE
LOWEST VSBYS ARE IN THE 3 TO 5 MILE RANGE AND MORE SO ASSOCIATED
WITH THE PCPN IN OUR SOUTHERN ZONES.
A SURFACE TROUGH/COOL FRONT CROSSES THE PLAINS DURING THE
DAY...SWITCHING WINDS NORTHERLY AND SCOURS THE LLVL MOISTURE TO
THE EAST. COOLER AIR IS SLOW TO ADVECT SOUTH AND WE ARE STILL
LOOKING FOR RATHER MILD HIGHS IN THE 40S/50S THIS AFTN AIDED BY
OUR WARM START. A COLDER AIRMASS SETTLES SOUTH OVERNIGHT AS A
STRONG HIGH PRESSURE SYSTEM BUILDS SOUTH AND EAST FM THE DAKOTAS.
IN THE COOLER/DRIER AIRMASS...LOWS ARE EXPECTED TO AVERAGE IN THE
TEENS/20S. MODELS SUGGEST THAT LOW CLOUD COVER WILL BE ON THE
PERIPHERY OF OUR SOUTHEAST CWA AND NAM/MET GUIDANCE INDICATES
POTENTIAL FOR FOG ON THE EDGE OF LOW CLOUDS TOWARD THE KRSL AREA.
SREF VSBY PROGS KEEP FOG POTENTIAL FARTHER EAST AND WITH NORTHERLY
WIND COMPONENT...HAVE LEFT FOG OUT OF FORECAST.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 326 AM CST FRI DEC 5 2014
PRIMARY FORECAST CONCERN THROUGH THE LONG TERM LIES MAINLY WITH LATE
WEEKEND PRECIPITATION CHANCES.
EXPECTING DRY CONDITIONS TO START OFF THE PERIOD ON SATURDAY...WITH
MODELS IN GOOD AGREEMENT SHOWING THE AREA UNDER THE INFLUENCE OF
UPPER LEVEL SHORTWAVE RIDGING SLIDING EAST...SET UP BETWEEN A
DISTURBANCE MAKING ITS WAY THROUGH THE MIDWEST...AND ANOTHER WORKING
THROUGH THE 4 CORNERS REGION AND ROCKIES. AT THE SURFACE...EXPECTING
THE CWA TO BE SITTING UNDER A RIDGE AXIS...EXTENDING FROM THE PARENT
HIGH LOCATED OVER NRN MN. BRINGING LIGHTER NRLY WINDS TO START THE
DAY...WINDS WILL GRADUALLY BECOME MORE EASTERLY THROUGH THE MORNING
HOURS...THEN SOUTHEASTERLY BY LATE AFTERNOON AS THAT HIGH/RIDGE AXIS
PUSHES EAST OF THE CWA. SITTING UNDER A COOLER AIRMASS...FORECAST
HIGHS CURRENTLY RANGE FROM THE UPPER 30S IN THE NORTHEAST TO THE
LOWER/MID 40S OVER THE WEST.
GREATER UNCERTAINTY IN THE FORECAST ARRIVES AS WE GET INTO THE LATE
OVERNIGHT HOURS SATURDAY NIGHT INTO SUNDAY...AS THAT ABOVE MENTIONED
UPPER LEVEL DISTURBANCE EMERGES OUT OF THE ROCKIES AND ONTO THE
PLAINS. EXPECTING CONDITIONS PRIOR TO MIDNIGHT TO REMAIN DRY...BUT
MODELS SHOW INCREASING LOWER LEVEL MOISTURE WITH TIME
/THOUGH NOT SIGNIFICANTLY/...THANKS TO MORE SOUTHERLY SFC/LL WINDS.
FORECAST SOUNDINGS REFLECT THAT...SHOWING THE LOWEST LAYERS BECOMING
SATURATED WITH TIME...WITH LIFT PICKING UP AS THAT UPPER LEVEL
DISTURBANCE INCHES CLOSER. CONCERNED ABOUT PRECIPITATION DEVELOPING
ACROSS PORTIONS OF THE CWA...HAD INHERITED A MENTION IN THE PRE DAWN
HOURS SUNDAY AND DECIDED TO KEEP IT GOING. DECIDED TO GO WITH A DZ
MENTION WITH THERE BEING A DRIER LAYER IN PLACE ABOVE THAT LOWER
LEVEL SATURATION. AS MENTIONED...CONFIDENCE IS NOT HIGH IN ITS
OCCURRENCE...BUT CANT COMPLETELY RULE IT OUT EITHER. HAVE SOME LOW
POPS GOING AFTER 12Z...AS THE LIFT CONTINUES TO INCREASE AS THE WAVE
PASSES...THINKING THAT DURING THE AFTERNOON HOURS THE BETTER CHANCES
WILL SHIFT EAST OF THE CWA...SO ONLY HAVE THE FAR EAST WITH SOME
LINGERING POPS. THE MAIN QUESTION WITH THE EARLY MORNING
PRECIPITATION IS WHERE WILL TEMPERATURES END UP. THOUGHTS ARE THAT
TEMPS WILL LEVEL OFF /PERHAPS RISE A FEW DEGREES/ ONCE THE THICKER
CLOUD COVER/BETTER MOISTURE MOVES IN...BUT WITH THE POTENTIAL FOR
TEMPS TO BE HOVERING AROUND THAT FREEZING MARK SHOULD THE PRECIP
DEVELOP...FELT A LIGHT FZDZ/FZRA MENTION SHOULD BE INCLUDED WITH THE
LIQUID MENTION. AT THIS POINT...SHOULD FREEZING PRECIP OCCUR...IT IS
NOT EXPECTED TO CAUSE NOTABLE PROBLEMS...AS IT WOULD BE LIGHT...AND
SHORT LIVED WITH TEMPS INCREASING AFTER SUNRISE. WITH THIS BEING IN
THE 4TH PERIOD...STILL SOME TIME TO ADJUST BASED ON HOW MODELS
TREND. OTHERWISE FOR SUNDAY...SHOULD BE PLENTY OF CLOUD COVER
AROUND...ESP IN THE EAST...BUT EXPECTING A REBOUND IN TEMPS...WITH
HIGHS RANGING FROM THE MID 40S EAST TO LOWER 50S WEST.
LOOKING AHEAD TO THE UPCOMING WORK WEEK MONDAY THROUGH THURSDAY...NO
SIGNIFICANT CHANGES WERE MADE TO THE FORECAST. IT REMAINS DRY AT
THIS POINT...WITH MODELS GENERALLY IN GOOD AGREEMENT SHOWING A LACK
OF NOTABLE SYSTEMS MOVING THROUGH GENERALLY NORTHWESTERLY FLOW IN
THE UPPER LEVELS...THOUGH WEAKER DISTURBANCES MOVING THROUGH IS A
POSSIBILITY. JUST TOO MUCH UNCERTAINTY AT THIS POINT TO INSERT ANY
PRECIP MENTION. NOT EXPECTING ANY BIG SWINGS IN TEMPERATURES THROUGH
THIS TIME FRAME...SHOULD SEE A BIT OF A WARMING TREND...WITH HIGHS
FOR WED/THUR BACK IN THE MID 50S FOR MOST OF THE CWA.
&&
.AVIATION...(FOR THE 06Z KGRI/KEAR TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1117 PM CST THU DEC 4 2014
AN UPPER LOW PRESSURE SYSTEM WILL CROSS THE CENTRAL PLAINS
TONIGHT...TRACKING ACROSS KANSAS. PRECIPITATION ASSOCIATED WITH
THE SYSTEM WILL REMAIN SOUTH OF THE TERMINAL AND CLOUDS WILL
REMAIN AT VFR. THERE IS THE POTENTIAL FOR FOG DEVELOPMENT...MORE
SO TOWARD KGRI THAN KEAR BUT MODELS ARE NOT CONSISTENT ON HOW FAR
WEST THE THE FOG WILL BE AND WILL MONITOR TRENDS.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...FAY
LONG TERM...ADP
AVIATION...FAY
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
1052 PM MST THU DEC 4 2014
.UPDATE...
HAVE GONE AHEAD AND CANCELLED THE WINTER WX ADVY A BIT
EARLY...RADAR ECHOES HAVE REALLY TAPERED OFF AND SATELLITE IMAGERY
AND LATEST MODELS HAVE THE UPPER TROUGH AXIS NEAR THE TX BORDER
SOON. MORE CONCERN IS THE AMOUNT OF FOG SHOWING UP. WILL SEND OUT
A ZFP UPDATE SHORTLY TO HAVE WIDESPREAD FOG WORDING TONIGHT FOR
THE CENTRAL AND WEST...AREAS IN THE EAST. SOME LOCALIZED DENSE FOG
LIKELY AS WELL. CONSIDERED AN ADVISORY BUT CONFIDENCE LOW FOR ANY
PARTICULAR AREA.
&&
.AVIATION...
06Z TAF CYCLE
RECIPITATION HAS TURNED MUCH LIGHTER...MORE SPARSE...AND SHOWERY
AND THE FOCUS WILL NOW SHIFT TO LOW STRATUS CLOUDS AND FOG ACROSS
NORTHERN AND CENTRAL NEW MEXICO. THE FOG AND LOW CLOUDS WILL LEAD TO
WIDESPREAD MVFR CONDITIONS AND SCATTERED TO LOCALIZED IFR AND EVEN
LIFR CONDITIONS. THE DENSER FOG AND LOWER STRATUS CLOUD DECKS WILL
BE MOST COMMON AND PREVALENT ALONG AND WEST OF THE CENTRAL MOUNTAIN
CHAIN OF NEW MEXICO WITH SOME SHELTERED VALLEY LOCATIONS OBSERVING
VISIBILITY AS LOW AS ONE QUARTER OF A MILE. CONFIDENCE IN THE
DEVELOPMENT OF FOG EAST OF THE MOUNTAINS IS NOT AS HIGH...BUT IT
CANNOT BE RULED OUT. THIS ACTIVITY WILL GRADUALLY BURN OFF THROUGH
THE LATE MORNING FRIDAY WITH LOW PROBABILITY FOR A FEW STRAY AND
LINGERING SHOWERS IN THE NORTHERN MOUNTAINS.
52
&&
.PREV DISCUSSION...322 PM MST THU DEC 4 2014...
.SYNOPSIS...
WET WEATHER WILL CONTINUE INTO THIS EVENING FOR MUCH OF THE REGION
BEFORE SLOW CLEARING DEVELOPS OVERNIGHT. SNOW ACCUMULATIONS WILL BE
GENERALLY LIGHT AND CONFINED TO AREAS ABOVE 9000 FEET. HIGH PRESSURE
WILL RETURN TO THE AREA BRIEFLY ON FRIDAY. THE NEXT STORM SYSTEM WILL
MOVE IN SATURDAY WITH THICK CLOUD COVER AND SHOWERS. SNOW LEVELS WILL
BE LOWER WITH THE NEXT SYSTEM HOWEVER AMOUNTS WILL STILL BE LIGHT.
SLIGHTLY ACTIVE WEATHER IS EXPECTED THROUGH NEXT WEEK WITH AT LEAST
SOME CHANCES FOR SHOWERS...PARTICULARLY IN THE HIGHER TERRAIN.
TEMPERATURES WILL REMAIN ABOVE NORMAL THROUGH MUCH OF NEXT WEEK.
&&
.DISCUSSION...
LATEST RADAR LOOP THIS AFTERNOON SHOWING THE MOST WIDESPREAD PRECIP
ON SCOPE IN QUITE SOME TIME. THE AXIS OF THE UPPER WAVE PER SATELLITE
IMAGERY IS STILL POISED ALONG THE NM/AZ BORDER...AND MOVING QUICKLY
EAST. THE 18Z HRRR AND NAM AGREE PRECIP WILL SLOWLY TAPER OFF DURING
THE MID/LATE EVENING HOURS MOST AREAS...AND LINGER ALONG WEST SLOPES
OF THE NORTHERN HIGH TERRAIN. CURRENTLY SNOW LEVELS ARE IMPRESSIVELY
HIGH WITH TEMPS NEAR FREEZING STILL AROUND 11KFT. COLD ADVECTION
WITH THE APPROACHING TROUGH AXIS WILL LOWER SNOW LEVELS TO 9KFT THIS
EVENING THEN ABOUT 8KFT BY SUNRISE. THAT TREND IS ALSO REFLECTED IN
THE MIN TEMP FORECAST WHICH RUNS ABOUT 5-15F ABOVE NORMAL.
WEAK RIDGING NOTED BEHIND THIS SYSTEM ALREADY ON WATER VAPOR IMAGERY
WILL BE SHORT-LIVED AS THE NEXT STREAM OF THICK HIGH CLOUDS IS ON
THE MOVE OVER THE EASTERN PACIFIC. INCREASED CLOUD COVER AND POPS
SLIGHTLY FOR SATURDAY/SATURDAY NIGHT. QPF WITH THIS SYSTEM IS PROGGED
MUCH LOWER THAN THIS CURRENT SYSTEM AND THE SOURCE REGION OF MID/
UPPER LEVEL MOISTURE IS NOT SO MUCH SUBTROPICAL...BUT STILL WOULD
NOT BE SURPRISED FOR MODELS TO CONTINUE TRENDING DEEPER AND WETTER.
NONETHELESS...PRECIP MODE LOOKS MORE CONVECTIVE THAN STRATIFORM.
700MB COLD ADVECTION WILL BE SLIGHTLY BETTER AND THICKNESS VALUES
DECREASE BUT STILL SNOW LEVELS WILL BE PRETTY HIGH FOR DECEMBER.
LOCATIONS ABOVE 8KFT COULD SEE A FEW INCHES OF SNOW...WITH QPF ON
THE ORDER OF 0.10-0.20 FOR LOWER ELEVATIONS. ASSOCIATED PWAT VALES
FROM THE NAM AND GFS AT KABQ NEAR 0.50 INCHES.
ANOTHER BREAK IN THE ACTION IS ON TAP FOR SUNDAY HOWEVER IT STILL
LOOKS LIKE HIGH LEVEL MOISTURE WILL KEEP HIGH CLOUDS AROUND. SEVERAL
WEATHER DISTURBANCES ARE ADVERTISED THROUGH NEXT WEEK BUT TIMING AND
STRENGTH ARE IN QUESTION. THERE ARE AT LEAST SLIGHT CHANCES WITH
RETURN FLOW FROM THE CENTRAL MT CHAIN EASTWARD. THE GFS AND ECMWF
ARE STILL SHOWING A BIG STORM SYSTEM LATE NEXT WEEK.
GUYER
&&
.FIRE WEATHER...
WET WEATHER SYSTEM WILL EJECT EASTWARD TONIGHT LEAVING SEVERAL
INCHES OF SNOW ACCUMULATION MAINLY ABOVE 8000 FT IN THE NORTHERN
MOUNTAINS. MIN HUMIDITIES ON FRIDAY WILL FALL 14 TO 30 DEGREES AS A
WEAK RIDGE OF HIGH PRESSURE CROSSES FROM THE WEST. THERE WILL ALSO
BE WIDESPREAD POOR VENTILATION ON FRIDAY WEST OF THE EASTERN TIER OF
COUNTIES AS TEMPERATURES RISE A FEW TO 5 DEGREES IN MOST PLACES.
ANOTHER UPPER LEVEL TROUGH WILL CROSS FROM THE WEST WITH WIDESPREAD
PRECIPITATION SATURDAY AND SATURDAY NIGHT. AT THIS TIME
SOUTHERN...CENTRAL AND NORTHWEST AREAS LOOK FAVORED FOR WETTING
PRECIPITATION WITH SPOTTIER AND LIGHTER PRECIP ACROSS THE NORTHEAST.
IT SHOULD BE ANOTHER WARM SYSTEM WITH 700 MB TEMPERATURES ONLY
DROPPING TO BETWEEN 0 AND 2 DEGREES. THE NORTHERN MOUNTAINS SHOULD
ACCUMULATE A FEW TO SEVERAL INCHES OF SNOW ABOVE 9000 FT
AGAIN...WITH THE HIGHER AMOUNTS ON WEST FACING SLOPES. THERE WILL BE
VENTILATION IMPROVEMENT IN MOST PLACES SATURDAY...BUT POCKETS OF
POOR VENTILATION WILL PERSIST MAINLY ACROSS EAST CENTRAL AND
NORTHWEST AREAS. TEMPERATURES WILL TREND DOWNWARD AGAIN IN MOST
PLACES SATURDAY.
ANOTHER RIDGE OF HIGH PRESSURE WILL CROSS ALOFT SUNDAY BEFORE THE
FLOW TURNS ZONAL ON MONDAY. THIS WILL RESULT IN A TWO DAY WARMING
AND DRYING TREND IN MOST PLACES WITH WIDESPREAD POOR VENTILATION BOTH
DAYS. THERE SHOULD BE POCKETS OF FAIR TO GOOD VENTILATION EAST OF
THE CENTRAL MOUNTAINS.
MODELS ARE IN FAIR AGREEMENT ON A WEAKER UPPER LEVEL TROUGH CROSSING
TUESDAY BEFORE A RIDGE ON WEDNESDAY. TUESDAYS TROUGH COULD TRIGGER
A FEW LIGHT SHOWERS OVER THE MOUNTAINS AND SE AREAS. AFTER SOME
VENTILATION IMPROVEMENT WITHIN 50 MILES OF THE I-40 CORRIDOR
TUESDAY...WIDESPREAD POOR VENTILATION IS EXPECTED AGAIN ON
WEDNESDAY. HIGH TEMPERATURES WILL ALSO FALL A FEW DEGREES THEN REBOUND
WEDNESDAY.
44
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
649 PM EST SAT DEC 6 2014
.SYNOPSIS...
A COLD FRONT WILL PUSH OFF THE COAST TONIGHT...BRINGING BREEZY
NORTH WINDS AND COOL TEMPERATURES FOR SUNDAY AND MONDAY. SHOWERS
ARE EXPECTED AHEAD OF THE FRONT TONIGHT...WITH A PERIOD OF RAIN
POSSIBLE MONDAY AS LOW PRESSURE DEVELOPS ALONG THE FRONT OFFSHORE.
BELOW-NORMAL TEMPERATURES AND DRY WEATHER IS ANTICIPATED THE
REMAINDER OF NEXT WEEK AS CANADIAN HIGH PRESSURE MAINTAINS
CONTROL.
&&
.NEAR TERM /THROUGH SUNDAY/...
AS OF 645 PM SATURDAY...SCATTERED AREAS OF RAIN ARE MAINLY EAST OF
A LUMBERTON TO KINGSTREE LINE AND CONTINUES MOVING OFF TO THE
EAST. ALOFT A SHORTWAVE IS SEEN IN WATER VAPOR IMAGERY MOVING OFF
AND THE DEEPER MOISTURE IS COINCIDENT WITH SHOWER ON THE RADAR.
THE COLD FRONT IS STILL WELL WEST OF THE AREA WITH A WEDGE IN
BETWEEN.
THE 21 UTC HRRR IS STILL SHOWING A FRONTAL PASSAGE AROUND 4 UTC
AND THE PRECIPITATION SHOULD MOVE OFF THE COAST AN 1 OR 2 BEFORE
THE FRONT.
NORTHERLY WINDS WILL PICK UP OVERNIGHT IN THE WAKE OF FROPA...WITH
RESULTING COLD ADVECTIVE SURGE HELPING DRIVE TEMPERATURES BACK
DOWN INTO THE MID 40S BY DAYBREAK ON SUNDAY.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH MONDAY NIGHT/...
AS OF 300 PM SATURDAY...1045 MB ARCTIC HIGH PRESSURE OVER SOUTHERN
QUEBEC WILL CREATE BREEZY NORTH WINDS ACROSS THE EASTERN CAROLINAS
SUNDAY. GIVEN ANTICIPATED MIXING PROFILES AND 1000-2000 FOOT WIND
SPEEDS GUSTS HERE AT THE SURFACE SHOULD REACH 30 MPH. TONIGHT`S
COLD FRONT SHOULD MOVE SEVERAL HUNDRED MILES OFFSHORE BEFORE
STALLING LATE IN THE DAY. MOISTURE CAUGHT WITHIN THE FRONTAL
INVERSION BETWEEN 2000-5000 FEET AGL SHOULD RESULT IN PLENTY OF
CLOUDS EARLY IN THE DAY...GRADUALLY CLEARING AS DRIER AIR ARRIVES
ON NORTHEAST WINDS WITHIN THIS LAYER. DESPITE INCREASING SUNSHINE
HIGHS SHOULD ONLY REACH 50-55.
LOW PRESSURE WILL DEVELOP SUNDAY NIGHT ALONG THE STALLED FRONT
OFFSHORE. MODELS PAINT A VARIETY OF SCENARIOS FOR WHERE THE LOW
DEVELOPS AND HOW IT LATER MOVES. MY PREFERRED MODELS ARE THE 00Z
AND 12Z ECMWF WHICH DEVELOP THE LOW ABOUT 400 MILES SE OF CAPE
FEAR...THEN BACK IT UP TO WITHIN ABOUT 200 MILES OF SHORE MONDAY
EVENING BEFORE TURNING NORTH AND ACCELERATING INTO THE MID-
ATLANTIC REGION. THIS WILL MAINTAIN A NORTHERLY BREEZE THROUGH THE
PERIOD AND PROMISES AT LEAST A CHANCE OF RAIN MONDAY AFTERNOON &
EVENING AS SHALLOW ISENTROPIC LIFT DEVELOPS ALONG THE 295K THETA
SURFACE...APPROXIMATELY 5000-7000 FEET AGL. THIS SHOULD NOT BE A
MAJOR RAIN EVENT...ONE-TENTH OF AN INCH OR LESS IS FORECAST WITH
THE BEST POTENTIAL NORTH OF MYRTLE BEACH AND FLORENCE WHERE THE
ISENTROPIC SURFACES ARE PROGGED TO BE STEEPEST.
ANY RESIDUAL RAIN SHOULD TAPER OFF MONDAY NIGHT AS THE SURFACE
LOW MOVES NORTHWARD WELL OFF THE NC COAST. SURFACE WINDS WILL BACK
MORE NORTHWESTERLY WITH TIME BRINGING DRIER AIR INTO THE AREA.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 300 PM SATURDAY...MEDIUM RANGE GUIDANCE CONTINUES TO PAINT A RATHER
UNEVENTFUL PERIOD FROM A POP PERSPECTIVE ALBEIT COOL SCENARIO
THROUGH THE UPCOMING WEEK. A DEEP CYCLONIC FLOW ALOFT WILL DEVELOP
AS A SECONDARY TROUGH PUSHES ACROSS TUESDAY. LOW PRESSURE WILL
EVENTUALLY CUTOFF ACROSS THE NORTHEAST COAST AND BE SLOW TO
MOVE/FILL. TEMPERATURES WILL BE BELOW CLIMATOLOGY THROUGHOUT AND THE
COLD AIR WILL BE REINFORCED WEDNESDAY WITH A SECONDARY TROUGH. HIGHS
WILL REMAIN IN THE 50S JUST BARLEY WEDNESDAY. LOWS WILL BE MODERATED
EARLY BY WINDS IN THE BOUNDARY LAYER REMAINING ELEVATED. BY FRIDAY
AND SATURDAY WHEN MORE CONDUCIVE RADIATIONAL CONDITIONS DEVELOP
THERMAL PROFILES WARM SLIGHTLY. OVERALL EXPECT LOWER TO MIDDLE 30S
FOR LOWS WITH THE EXCEPTION OF A SMATTERING OF 20S WEDNESDAY MORNING
IN THE NORTHWEST ZONES.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
AS OF 00 UTC...MVFR/IFR DUE TO AREAS OF FOG AND LOW CIGS THROUGH
TONIGHT...ALONG WITH SCATTERED SHOWERS ALONG THE COAST. A COLD
FRONT WILL PUSH THROUGH THE AREA OVERNIGHT ALLOWING FOR CONDITIONS
TO IMPROVE BEHIND THE FEATURE...ALONG WITH GUSTY NORTH WINDS.
WITH LIGHT AND VARIABLE WINDS...THE INLAND TERMINALS ARE EXPERIENCE
MVFR DUE TO LOW CIGS AND PATCHY FOG WITH VFR ALONG THE COAST. LATEST
RADAR IMAGERY DEPICTS A LINE OF SHOWERS MOVING EASTWARD TOWARDS THE
COAST...WHICH WILL IMPACT THE COASTAL SITES OVER THE NEXT FEW HOURS.
AS A RESULT...ANTICIPATE CONDITIONS TO DETERIORATE TO MVFR/POSSIBLE
IFR ALONG THE COAST AS WELL. AS AN APPROACHING COLD FRONT PUSHES
ACROSS THE AREA LATER TONIGHT...A WINDSHIFT TO THE NORTH WILL OCCUR
WITH GUSTY WINDS TO AROUND 25 KTS THROUGHOUT THE REMAINDER OF THE
PERIOD. EXPECT CONDITIONS TO GRADUALLY IMPROVE TO VFR/MVFR TOWARDS
SUNDAY EVENING.
EXTENDED OUTLOOK...PERIODS OF MVFR/IFR CIGS ARE LIKELY THROUGH THE
WEEKEND AND INTO EARLY NEXT WEEK. GUSTY NORTH WINDS MON BEHIND
THE COLD FRONT. BECOMING VFR DURING TUE. VFR WED THROUGH THURS.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 630 PM SATURDAY...SOUTH TO SOUTHWEST WINDS BETWEEN 5 AND
10 KNOTS ARE OCCURRING OVER THE WATERS THIS EVENING AS WEAK HIGH
PRESSURE GIVES WAY TO A COLD FRONT BY MIDNIGHT...WITH NORTHERLY
WINDS IN ITS WAKE PICKING UP TO 20 TO 25 KTS BY DAYBREAK ON
SUNDAY. SEAS WILL BUILD TO 5 FT WELL OFFSHORE BY THEN.
SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 300 PM SATURDAY...LOW PRESSURE WILL DEVELOP ABOUT 400 MILES
SOUTHEAST OF CAPE FEAR SUNDAY AFTERNOON. WHILE THE LOW WILL NOT
BE TOO STRONG INITIALLY...THE PRESSURE GRADIENT BETWEEN IT AND
1045 MB ARCTIC HIGH PRESSURE OVER SOUTHERN CANADA WILL BE QUITE
PRONOUNCED. THIS WILL FEED INTO STRENGTHENING NORTHERLY LOW LEVEL
WINDS ALONG THE EASTERN SEABOARD SUNDAY AND SUNDAY NIGHT.
AS YOU MIGHT EXPECT MODELS OFFER A VARIETY OF SOLUTIONS BUT THE
BEST APPEARS TO BE THE 00Z/12Z ECMWF WHICH BRINGS THE STRONGEST
NORTHERLY WINDS ACROSS THE AREA LATE SUNDAY AFTERNOON INTO SUNDAY
NIGHT. THE POTENTIAL FOR GALE-FORCE WINDS ACROSS THE NC WATERS IS
PROBABLY BETTER THAN 50-50 AND A GALE WATCH REMAINS IN EFFECT.
ACROSS THE SC WATERS WINDS SHOULD BE A LITTLE WEAKER...BUT AFTER
COLLABORATION WITH NWS CHARLESTON WE HAVE EXTENDED THE GALE WATCH
THERE AS WELL. ACROSS OPEN WATERS INSIDE 20 MILES FROM SHORE SEAS
SHOULD BUILD TO 6-10 FEET DURING THE HEIGHT OF THE EVENT.
WIND SPEEDS SHOULD DIMINISH MONDAY AS THE PRESSURE GRADIENT
WEAKENS WITH INCREASING EASTWARD DISPLACEMENT OF THE ARCTIC HIGH
ACROSS SOUTHEASTERN CANADA. THE SURFACE LOW IS EXPECTED TO MOVE
WESTWARD TOWARD THE COAST MONDAY...TURNING NORTHWARD MONDAY EVENING
ABOUT 200 MILES EAST OF CAPE FEAR. NORTH WINDS WILL GRADUALLY BACK
MORE NORTHWESTERLY LATE MONDAY NIGHT AS THE LOW MOVES INTO THE
MID-ATLANTIC REGION.
LONG TERM /TUESDAY THROUGH THURSDAY/...
AS OF 300 PM SATURDAY...ONCE AGAIN NOT THE BEST OF CONDITIONS FOR THE
MARINE COMMUNITY ALTHOUGH WINDS WILL BE LOWER WHEN COMPARED TO THE
PREVIOUS COUPLE OF DAYS IN THE FORECAST. EXPECT NORTHWEST WINDS OF
10-15 KNOTS THROUGH THE PERIOD. THERE WILL BE A SLIGHT INCREASE
EARLY WEDNESDAY MORNING TO 15-20 KNOTS AS ANOTHER SHORTWAVE DIVES
THROUGH THE LONG WAVE TROUGH KICKING UP WINDS. WINDS ON THURSDAY
WILL BE ON THE LOWER END OF THE 10-15 KNOT RANGE. SEAS WILL BE MOST
ELEVATED ACROSS THE OUTER WATERS WITH THE OFFSHORE FLOW. SMALL CRAFT
SEAS WILL LINGER TUESDAY AND WEDNESDAY BEFORE DROPPING OFF
THURSDAY.
&&
.TIDES/COASTAL FLOODING...
AS OF 300 PM SATURDAY...STRONG NORTHERLY WINDS WILL DEVELOP SUNDAY
AFTERNOON INTO MONDAY NIGHT IN THE GRADIENT BETWEEN ARCTIC HIGH
PRESSURE TO THE NORTH AND LOW PRESSURE DEVELOPING WELL OFFSHORE.
THE FULL MOON WAS TODAY SO TIDAL RANGES WILL STILL BE LARGER THAN
TYPICAL SUNDAY AND MONDAY. THE CURRENT ETSURGE MODEL INCORPORATES
A LITTLE LESS THAN ONE FOOT OF STORM SURGE INTO ITS OUTPUT WHICH
PLACES MONDAY MORNING`S HIGH TIDE ABOUT 0.40 FEET BELOW MINOR
FLOOD CRITERIA AT MYRTLE BEACH. WE WILL CONTINUE TO MONITOR TRENDS
IN PREDICTED TIDES CLOSELY AS ANY SUBTLE VEERING OF WIND DIRECTION
OR INCREASE IN WIND SPEED COULD PUSH WATER LEVELS HIGHER.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...GALE WATCH FROM 6 AM EST SUNDAY THROUGH LATE SUNDAY NIGHT FOR
AMZ250-252-254-256.
&&
$$
NEAR TERM...HAWKINS
SHORT TERM...TRA
LONG TERM...SHK
AVIATION...SGL
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
544 PM EST FRI DEC 5 2014
.SYNOPSIS...
HIGH PRESSURE WILL MOVE OFFSHORE TONIGHT. COASTAL TROUGH WILL LIFT
NORTH AS A WARM FRONT ON SATURDAY...AHEAD OF A COLD FRONT WHICH
WILL CROSS OFFSHORE SATURDAY NIGHT. THIS COLD FRONT WILL BRING A
PERIOD OF SHOWERS WITH AN ISOLATED THUNDERSTORM POSSIBLE. A STRONG
WEDGE OF HIGH PRESSURE WILL BUILD SOUTH SUNDAY AND
MONDAY...BRINGING GUSTY NORTH WINDS AND MUCH COOLER TEMPERATURES. CANADIAN
HIGH PRESSURE NEXT WEEK WILL MAINTAIN SEASONABLY COOL TEMPERATURES
AND DRY CONDITIONS.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
AS OF 300 PM FRIDAY...A MIX OF HIGH AND MID-LEVEL CLOUDS EMBEDDED
IN A DEEP WESTERLY FLOW STREAMING ACROSS THE FORECAST AREA THIS
AFTERNOON. TEMPERATURES HAVE NOW PEAKED IN THE LOWER TO MID 60S.
WEAK WEDGE-STYLE PATTERN WILL CONTINUE TO BREAK DOWN THROUGH THE
DAYLIGHT HOURS AND WILL BE JUST ABOUT EXTINCT BY THIS EVENING AS A
FLATTENED UPPER RIDGE GIVES WAY TO BROAD TROUGHING. A COLD FRONT
APPROACHING FROM THE WEST WILL REMAIN WEST OF THE APPALACHIANS BY
THE END OF THE PERIOD. SATELLITE LOOPS AND GUIDANCE INDICATE PRESENT
AMPLE MIX OF CIRRUS AND MID LEVEL CLOUDS WILL CONTINUE THROUGH THE
OVERNIGHT PERIOD AS A WEAK TROUGH FORMS OFFSHORE. ISOLATED SHOWERS
POSSIBLE ALONG THE COAST IN THE EARLY MORNING HOURS OF SATURDAY AS
THIS TROUGH APPROACHES THE COAST. PATCHES TO AREAS OF FOG EXPECTED
OVERNIGHT AS DEWPOINTS ARE EXPECTED TO REMAIN ELEVATED IN THE UPPER
40S TO LOWER 50S...WHICH IS WHAT THE MINIMUM TEMPERATURES ARE
FORECAST TO BE ACCORDING TO A CONSENSUS OF GUIDANCE.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/...
AS OF 300 PM FRIDAY...COASTAL TROUGH LIFTING NORTH AS A WARM
FRONT SATURDAY MORNING WILL CREATE A WARM DAY...ESPECIALLY ALONG
THE COAST...BUT RAIN CHANCES WILL INCREASE RAPIDLY LATE IN THE
DAY. AS THE COASTAL TROUGH LIFTS NORTH EARLY...WAA WILL FOLLOW
THROUGH THE AFTN...WITH 850MB TEMPS CLIMBING TO AROUND 10C BY
SATURDAY AFTN. AS THIS OCCURS HOWEVER...CLOUD COVER WILL BE ON THE
INCREASE THANKS TO MOIST ADVECTION AND PVA AHEAD OF A SHORTWAVE
WHICH WILL MOVE JUST NORTH OF THE AREA SATURDAY NIGHT. BENEATH
THIS SHORTWAVE...A SURFACE LOW WILL PUSH EAST NEAR THE NC/VA
BORDER...DRAGGING A COLD FRONT ACROSS THE CWA SATURDAY NIGHT. AS
PWATS RISE TO ABOUT 1.25 INCHES AND MID-LEVEL LAPSE RATES CLIMB
TOWARDS 7C/KM...SCATTERED SHOWERS WITH ISOLATED TSTMS ARE
EXPECTED. INSTABILITY REMAINS MINIMAL...BUT CANNOT RULE OUT A FEW
LIGHTNING STRIKES...AND THIS IS ECHOED BY THE GENERAL RISK
ENCOMPASSING THE ILM CWA IN THE SWODY2. TOTAL QPF WILL NOT BE VERY
HIGH...BUT BRIEF PERIODS OF HEAVY RAIN IS POSSIBLE WITHIN A FEW
HOURS EITHER SIDE OF SATURDAY EVENING. COOL ADVECTION BEGINS IN
EARNEST BEHIND THE COLD FRONT LATE SATURDAY NIGHT...SO TEMPS WHICH
WILL RISE TOWARDS 70 ALONG THE COAST SATURDAY AFTN...MID 60S WELL
INLAND...WILL DROP RAPIDLY INTO THE LOW 40S WELL NW...TO AROUND 50
AT THE COAST...BY SUNDAY MORNING.
A QUIETER BUT MUCH COOLER DAY ON SUNDAY AS A STRONG WEDGE OF HIGH
PRESSURE DEVELOPS BEHIND THE COLD FRONT FROM SATURDAY NIGHT. WITH
LOW-LEVEL MOISTURE PROGGED TO REMAIN HIGH BENEATH THE WEDGE...PARTLY
TO MOSTLY CLOUDY CONDITIONS WILL PERSIST MUCH OF SUNDAY. THIS
COMBINED WITH COOL ADVECTION WILL LIMIT WARMING...AND HIGHS MAY BE
REACHED VERY EARLY IN THE DAY...WITH LITTLE DIURNAL RANGE. EXPECT
HIGHS ONLY IN THE LOW 50S IN THE FAR NORTH...TO MID 50S IN THE
SOUTH. SOME CLEARING WILL OCCUR VERY LATE...AND CONTINUED CAA WILL
HELP MINS FALL INTO THE UPPER 30S SUNDAY NIGHT.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 300 PM FRIDAY...THE MID LEVEL PATTERN WILL BE QUITE
PROGRESSIVE THROUGH THE PERIOD WITH THE AREA REMAINING VOID OF ANY
SIGNIFICANT PRECIPITATION. INITIALLY A LINGERING LOW PRESSURE
SYSTEM OFF THE SOUTHEAST COAST MAY PROVIDE A FEW SHOWERS...MORESO
ALONG THE COAST MONDAY BEFORE A COLD FRONT...ASSOCIATED WITH
FAIRLY STRONG SHORTWAVE MOVING THROUGH THE MIDWEST SWEEPS THE AREA
CLEAN. BEYOND THIS A WEAKENING CYCLONIC FLOW ALOFT WILL PREVAIL
ACROSS THE AREA. AT THE SURFACE...HIGH PRESSURE WILL BUILD DOWN
FROM THE UPPER MIDWEST TO ESSENTIALLY OVER THE AREA BY FRIDAY THUS
A DRY FORECAST. TEMPERATURES TRENDS LOOK A LITTLE BELOW
CLIMATOLOGY WITH HIGHS MOSTLY IN THE 50S AND LOWS IN THE LOWER TO
MIDDLE 30S
&&
.AVIATION /00Z SATURDAY THROUGH THURSDAY/...
AS OF 00Z...RATHER LOW CONFIDENCE ON THE BACK END OF THE FORECAST
PERIOD WITH RESPECT TO CEILINGS AND THE TIMING OF PRECIP. LOOKS LIKE
THERE COULD BE TWO BATCHES OF RAIN/SHOWERS: THE FIRST AROUND SUNRISE
WITH A COASTAL TROUGH...THEN ANOTHER ROUND IN THE LATE AFTERNOON
AHEAD OF A COLD FRONT. MODELS ARE IN REASONABLE AGREEMENT
INTRODUCING IFR STRATUS/FOG AROUND DAYBREAK IF NOT BEFORE...AND THIS
MAKES SENSE GIVEN THE WEAK WARM AIR ADVECTION. THE HRRR MODEL THINKS
THAT ILM STANDS THE BEST CHANCE FOR MORNING PRECIP...BUT THE MYRTLES
COULD ALSO GET INTO THE ACT. THINK THE MORNING PRECIP WILL GIVE WAY
TO MVFR CEILINGS AND SOUTHWESTERLY FLOW AHEAD OF A COLD FRONT WHICH
WILL ARRIVE AT THE END OF THE FORECAST PERIOD.
EXTENDED OUTLOOK...PERIODS OF MVFR/IFR CIGS ARE LIKELY THROUGH THE
WEEKEND AND INTO EARLY NEXT WEEK. GUSTY NORTH WINDS SUN/MON BEHIND
THE COLD FRONT. BECOMING VFR DURING TUE. VFR WED AND THU.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 300 PM FRIDAY...PRESENT MODEST NORTHEASTERLY FLOW WILL
CONTINUE UNTIL AROUND MIDNIGHT OR SO AS A WEDGE OF HIGH PRESSURE
EXTENDS SW ALONG THE APPALACHIANS. WINDS WILL BECOME LIGHT AND
MORE EASTERLY TOWARDS MORNING AS A WEAK TROUGH FORMS OVER THE
COASTAL WATERS. SEAS WILL HOVER RIGHT AROUND 3 FT THROUGH THE
PERIOD.
SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 300 PM FRIDAY...QUIET MARINE CONDITIONS TO START THE
PERIOD...BUT RAPID DETERIORATION IS EXPECTED ON SUNDAY. WEAK
COASTAL TROUGH WILL LIFT NORTH ON SATURDAY...WITH WINDS TURNING
FROM SE TO SW THROUGH THE AFTN...BUT AT LIGHT SPEEDS. LOW PRESSURE
MOVING NORTH OF THE AREA WILL DRAG A COLD FRONT ACROSS THE WATERS
SATURDAY NIGHT...AND WINDS WILL TURN ABRUPTLY TO THE NORTH AT
15-20 KTS BY SUNDAY MORNING. SEAS ON SATURDAY WILL BE GENERALLY
2-4 FT REGARDLESS OF WIND DIRECTION...BUT WILL BEGIN TO RISE LATE
BEHIND THE COLD FRONT.
GALE WATCH HAS BEEN HOISTED FOR THE NC WATERS BEGINNING SUNDAY
MORNING...AND THERE IS PRETTY HIGH CONFIDENCE IN A GALE OCCURRING
SUNDAY AS A STRONG WEDGE OF HIGH PRESSURE BUILDS DOWN THE COAST.
THIS WILL CAUSE A TIGHT GRADIENT OVER THE WATERS...AND WIND WILL
BECOME NE AT 20-30 KTS ON SUNDAY...WITH FREQUENT GUSTS TO 35 KTS OR
MORE EXPECTED ACROSS THE NC WATERS. THERE IS LOWER CONFIDENCE IN
GALE-FORCE WINDS ACROSS SC WATERS...BUT AT LEAST A STRONG SMALL
CRAFT ADVISORY IS EXPECTED. THESE STRONG WINDS WILL ALSO PUSH SEAS
UP TO TO 5-9 FT ON SUNDAY...WITH THE EXCEPTION BEING THE WAVE
SHADOWED REGION SW OF BRUNSWICK COUNTY.
LONG TERM /MONDAY THROUGH WEDNESDAY/...
AS OF 300 PM FRIDAY...NEXT WEEK WILL NOT BE THE BEST OF TIMES FOR THE
MARINE COMMUNITY AS BLUSTERY CONDITIONS AND ELEVATED SEAS WILL
CONTINUE. FOR MONDAY A POTENT NORTHERLY FLOW WILL CONTINUE AS LOW
PRESSURE MOVES WELL OFF TO THE NORTHEAST AND MASSIVE HIGH PRESSURE
BUILDS IN FROM THE NORTHWEST. EXPECT WINDS OF 20-25 KNOTS...POSSIBLY
HIGHER WITH CERTAIN SMALL CRAFT CONDITIONS AND POSSIBLY GALES. THE
WINDS DO DIMINISH THROUGHOUT THE DAY TO SETTLE AT 10-15 KNOTS BY
TUESDAY MORNING. HERE THE WINDS WILL REMAIN THROUGH WEDNESDAY. SEAS
WILL BE HIGHEST MONDAY WITH 3-6 FEET DROPPING TO 2-5 FEET TUESDAY
AND WEDNESDAY.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...GALE WATCH FROM SUNDAY MORNING THROUGH LATE SUNDAY NIGHT FOR
AMZ250-252.
&&
$$
SYNOPSIS...JDW
NEAR TERM...REK
SHORT TERM...JDW
LONG TERM...SHK
AVIATION...43
MARINE...REK/JDW/SHK
AREA FORECAST DISCUSSION
NWS BISMARCK ND
915 PM CST SAT DEC 6 2014
.UPDATE...
ISSUED AT 905 PM CST SAT DEC 6 2014
LATEST REGIONAL RADAR IMAGERY SHOWS BAND OF LIGHT RAIN WORKING ITS
WAY FROM CENTRAL INTO EASTERN MONTANA. LATEST HIGH-RES GUIDANCE
CONTINUES TO HAVE A GOOD GRASP ON THE PRECIPITATION BEING
PRESENT...BUT OVER THE PAST FEW RUNS HAS HELD IT TOO FAR NORTH.
WITH THIS...HAVE SPREAD PRECIP CHANCES FURTHER SOUTH A BIT AND
HAVE INCREASED POPS SOME OVER MUCH OF FAR WESTERN NORTH DAKOTA AS
MODELS CONTINUE TO HOLD THIS TOGETHER AS IT PUSHES EAST. BY THE
TIME IT REACHES OUR AREA...IT SHOULD BE MAINLY LIGHT FREEZING
RAIN WITH THE COOLER SURFACE TEMPS. UPDATES HAVE BEEN SENT.
UPDATE ISSUED AT 620 PM CST SAT DEC 6 2014
SOME LIGHT RADAR RETURNS SHOWING UP OVER CENTRAL MONTANA WITH
LIGHT RAIN BEING REPORTED IN LEWISTOWN. WILL WATCH HOW THIS
EVOLVES THROUGH THE EVENING AS IT PUSHES EAST AS HIGH-RES MODELS
CONTINUE TO BRING SOME OF THIS PRECIPITATION INTO WESTERN NORTH
DAKOTA AFTER MIDNIGHT. FORECAST SOUNDINGS STILL SUGGEST THAT IF
ANY PRECIPITATION DOES DEVELOP IT WILL BE FREEZING RAIN. CURRENT
FORECAST REFLECTS THIS WELL. ONLY CHANGE THAT WAS MADE FOR EARLY
EVENING UPDATE WAS TO INCREASE CLOUD COVER TO ACCOUNT FOR HIGH
CLOUDS COVERING MUCH OF THE AREA.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 333 PM CST SAT DEC 6 2014
THE MAIN FORECAST ISSUE IN THE SHORT TERM PERIOD WILL BE POSSIBLE
FREEZING PRECIPITATION TONIGHT AND SUNDAY.
CURRENTLY A SHORTWAVE TROUGH IS LOCATED OVER EASTERN WASHINGTON. THE
WAVE WILL TRACK ALONG THE INTERNATIONAL BORDER OVERNIGHT AND DEVELOP
A SURFACE LOW IN THE LEE OF THE ROCKIES. THE SURFACE/UPPER LEVEL LOW
IS PROGGED TO BE OVER NORTHEAST MT/SOUTH CENTRAL SK BY 12 UTC
SUNDAY. WARM ADVECTION AHEAD OF THE LOW WILL RESULT IN WARM
TEMPERATURES ALOFT ENCOMPASSING ALL OF WESTERN AND CENTRAL NORTH
DAKOTA TONIGHT. THUS THE POTENTIAL FOR FREEZING PRECIPITATION
THROUGH SUNDAY AFTERNOON.
THE LATEST 20 UTC RAP DEPICTS A BAND OF LIGHT REFLECTIVITIES MOVING
INTO WESTERN NORTH DAKOTA AROUND 08 UTC SUNDAY. HOWEVER...ANY
MEASURABLE PRECIPITATION REMAINS CONFINED TO THE FAR NORTHWEST
CORNER OF NORTH DAKOTA. THE RAP MAINTAINS THE LIGHT REFLECTIVITIES
AS THEY CROSS THE CWA BUT KEEPS MAINLY TRACE AMOUNTS...AND MAINLY
CONFINED TO THE FAR NORTHERN TIER COUNTIES. THE GFS/EC/GEM ALL
BRING VERY LIGHT QPF INTO THE FAR NORTHWEST THROUGH 12 UTC. THE
EC/GEM ALSO TRACK SOME TRACE AMOUNTS ALONG THE NORTHERN TIER
COUNTIES THROUGH THE MORNING. THE GFS IS FARTHER SOUTH AND IS ON
THE SOUTHERN SIDE OF THE ENVELOPE OF DETERMINISTIC SOLUTIONS. THUS
HAVE KEPT BEST CHANCE FOR QPF IN THE FAR NORTHWEST 06-12 UTC
SUNDAY AND ACROSS THE FAR NORTHERN TIER COUNTIES 12-18 UTC SUNDAY.
WILL STILL HAVE A MENTION OF SOME FREEZING RAIN SOUTHWEST AND
SOUTH CENTRAL (MAINLY ALONG AND NORTH OF I-94) BUT WITH NO
SIGNIFICANT ACCUMULATIONS. EVEN ACROSS THE NORTH...DETERMINISTIC
MODEL QPF REMAINS AT OR BELOW A HUNDREDTH OF AN INCH. ONLY A
LITTLE FREEZING RAIN CAN CAUSE SIGNIFICANT TRAVEL ISSUES. BUT WITH
LOW MODEL QPF...WILL HOLD OFF ON ANY HIGHLIGHTS AT THIS TIME. WE
WILL STILL HAVE TIME TO WATCH THINGS DEVELOP ACROSS NORTHEAST
MONTANA AND SOUTHERN SASKATCHEWAN THIS EVENING AND OVERNIGHT.
COULD STILL SEE A VERY LIGHT MIX OVER THE NORTH CENTRAL MONDAY
AFTERNOON. BUT WESTERN NORTH DAKOTA WILL BE ON THE BACK SIDE OF THE
MID LEVEL TROUGH WITH COLD ADVECTION TRACKING SOUTHEAST ACROSS THE
CWA DURING THE AFTERNOON. THUS THE WEST WILL QUICKLY TRANSITION TO
SNOW AND THE SOUTH CENTRAL SHOULD WARM UP ENOUGH TO SEE ALL RAIN
WITH A QUICK CHANGE TO SNOW AS THE COLD ADVECTION ARRIVES.
IT WILL ALSO BECOME BREEZY TO WINDY SUNDAY AFTERNOON FROM WEST TO
EAST BEHIND THE TRACK OF THE LOW. STRONGEST WINDS 20-30 MPH WITH
GUSTS TO 35 MPH WILL SPREAD FROM THE SOUTHWEST SUNDAY AFTERNOON INTO
THE CENTRAL LATE AFTERNOON TO EARLY EVENING. HIGHS SUNDAY WILL
LIKELY BE REACHED IN THE MORNING NORTH TO EARLY AFTERNOON SOUTH WITH
TEMPERATURES FALLING MID TO LATE AFTERNOON EVERYWHERE.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 333 PM CST SAT DEC 6 2014
POST FRONTAL NORTHWEST WINDS OF 20 TO 30 MPH ALONG WITH ISOLATED TO
SCATTERED SNOW SHOWERS WILL DOMINATE SUNDAY NIGHT. THE ENTIRE SYSTEM
DEPARTS CENTRAL NORTH DAKOTA BY 12Z MONDAY WITH COLDER AIR REMAINING
IN PLACE FOR THE MORNING FOLLOWED BY WARM AIR ADVECTION MONDAY
AFTERNOON ESPECIALLY IN THE WEST. A PROGRESSIVE PATTERN CONTINUES
WITH A TRANSITORY RIDGE SHIFTING THROUGH MONDAY NIGHT FOLLOWED BY A
DRY SHORTWAVE TROUGH PASSING THROUGH TUESDAY. THEREAFTER...UPPER
RIDGING DOMINATES AND SHIFTS EAST BY MIDWEEK ALLOWING A SOUTHWEST
FLOW TO RETURN. HOWEVER NOTHING FORESEEN IN THE SOUTHWEST FLOW IN
TERMS OF SIGNIFICANT SHORTWAVES AT LEAST THROUGH SATURDAY PER
GFS/GEM GLOBAL/SUPERBLEND. HOWEVER THE LATEST ECMWF PUSHES A FAST
MOVING SHORTWAVE AND CONSEQUENTLY LIGHT PRECIPITATION/FAVORING RAIN
SHOWERS AT THIS POINT...ACROSS THE NORTH THURSDAY. HIGH TEMPERATURES
WILL WARM TO BETWEEN 35F AND 45F WEDNESDAY THROUGH FRIDAY...THEN A
BIT COOLER FOR SATURDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 620 PM CST SAT DEC 6 2014
VFR CONDITIONS ARE EXPECTED THROUGH THE OVERNIGHT HOURS. LCL -FZRA
MAY MOVE INTO NORTHWEST/WEST CENTRAL NORTH DAKOTA AFTER 06Z AND
PUSH TOWARDS NORTH CENTRAL NORTH DAKOTA THROUGH THE MORNING HOURS.
HAVE LEFT THIS OUT OF INDIVIDUAL TERMINAL FORECASTS FOR NOW GIVEN
THE LOW COVERAGE...BUT WILL MONITOR THROUGH THE EVENING. A
SURFACE LOW WILL PASS TO THE NORTH ON SUNDAY. WINDS WILL SWITCH
TOWARDS THE WEST/NORTHWEST AS SOME AREAS OF PRECIPITATION AGAIN
DEVELOP...MAINLY OVER THE NORTHWEST. -RA/-FZRA WILL BE
POSSIBLE....WITH A TRANSITION TOWARDS -SN AS COOLER AIR MOVES IN
FROM NORTHWEST TO SOUTHEAST. CIGS WILL DIMINISH TO MVFR LEVELS
FROM NORTHWEST TO SOUTHEAST STARTING LATE MORNING AND CONTINUING
THROUGH THE AFTERNOON.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JJS
SHORT TERM...TWH
LONG TERM...KS
AVIATION...JJS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
634 PM CST SAT DEC 6 2014
.UPDATE...
ISSUED AT 620 PM CST SAT DEC 6 2014
SOME LIGHT RADAR RETURNS SHOWING UP OVER CENTRAL MONTANA WITH
LIGHT RAIN BEING REPORTED IN LEWISTOWN. WILL WATCH HOW THIS
EVOLVES THROUGH THE EVENING AS IT PUSHES EAST AS HIGH-RES MODELS
CONTINUE TO BRING SOME OF THIS PRECIPITATION INTO WESTERN NORTH
DAKOTA AFTER MIDNIGHT. FORECAST SOUNDINGS STILL SUGGEST THAT IF
ANY PRECIPITATION DOES DEVELOP IT WILL BE FREEZING RAIN. CURRENT
FORECAST REFLECTS THIS WELL. ONLY CHANGE THAT WAS MADE FOR EARLY
EVENING UPDATE WAS TO INCREASE CLOUD COVER TO ACCOUNT FOR HIGH
CLOUDS COVERING MUCH OF THE AREA.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 333 PM CST SAT DEC 6 2014
THE MAIN FORECAST ISSUE IN THE SHORT TERM PERIOD WILL BE POSSIBLE
FREEZING PRECIPITATION TONIGHT AND SUNDAY.
CURRENTLY A SHORTWAVE TROUGH IS LOCATED OVER EASTERN WASHINGTON. THE
WAVE WILL TRACK ALONG THE INTERNATIONAL BORDER OVERNIGHT AND DEVELOP
A SURFACE LOW IN THE LEE OF THE ROCKIES. THE SURFACE/UPPER LEVEL LOW
IS PROGGED TO BE OVER NORTHEAST MT/SOUTH CENTRAL SK BY 12 UTC
SUNDAY. WARM ADVECTION AHEAD OF THE LOW WILL RESULT IN WARM
TEMPERATURES ALOFT ENCOMPASSING ALL OF WESTERN AND CENTRAL NORTH
DAKOTA TONIGHT. THUS THE POTENTIAL FOR FREEZING PRECIPITATION
THROUGH SUNDAY AFTERNOON.
THE LATEST 20 UTC RAP DEPICTS A BAND OF LIGHT REFLECTIVITIES MOVING
INTO WESTERN NORTH DAKOTA AROUND 08 UTC SUNDAY. HOWEVER...ANY
MEASURABLE PRECIPITATION REMAINS CONFINED TO THE FAR NORTHWEST
CORNER OF NORTH DAKOTA. THE RAP MAINTAINS THE LIGHT REFLECTIVITIES
AS THEY CROSS THE CWA BUT KEEPS MAINLY TRACE AMOUNTS...AND MAINLY
CONFINED TO THE FAR NORTHERN TIER COUNTIES. THE GFS/EC/GEM ALL
BRING VERY LIGHT QPF INTO THE FAR NORTHWEST THROUGH 12 UTC. THE
EC/GEM ALSO TRACK SOME TRACE AMOUNTS ALONG THE NORTHERN TIER
COUNTIES THROUGH THE MORNING. THE GFS IS FARTHER SOUTH AND IS ON
THE SOUTHERN SIDE OF THE ENVELOPE OF DETERMINISTIC SOLUTIONS. THUS
HAVE KEPT BEST CHANCE FOR QPF IN THE FAR NORTHWEST 06-12 UTC
SUNDAY AND ACROSS THE FAR NORTHERN TIER COUNTIES 12-18 UTC SUNDAY.
WILL STILL HAVE A MENTION OF SOME FREEZING RAIN SOUTHWEST AND
SOUTH CENTRAL (MAINLY ALONG AND NORTH OF I-94) BUT WITH NO
SIGNIFICANT ACCUMULATIONS. EVEN ACROSS THE NORTH...DETERMINISTIC
MODEL QPF REMAINS AT OR BELOW A HUNDREDTH OF AN INCH. ONLY A
LITTLE FREEZING RAIN CAN CAUSE SIGNIFICANT TRAVEL ISSUES. BUT WITH
LOW MODEL QPF...WILL HOLD OFF ON ANY HIGHLIGHTS AT THIS TIME. WE
WILL STILL HAVE TIME TO WATCH THINGS DEVELOP ACROSS NORTHEAST
MONTANA AND SOUTHERN SASKATCHEWAN THIS EVENING AND OVERNIGHT.
COULD STILL SEE A VERY LIGHT MIX OVER THE NORTH CENTRAL MONDAY
AFTERNOON. BUT WESTERN NORTH DAKOTA WILL BE ON THE BACK SIDE OF THE
MID LEVEL TROUGH WITH COLD ADVECTION TRACKING SOUTHEAST ACROSS THE
CWA DURING THE AFTERNOON. THUS THE WEST WILL QUICKLY TRANSITION TO
SNOW AND THE SOUTH CENTRAL SHOULD WARM UP ENOUGH TO SEE ALL RAIN
WITH A QUICK CHANGE TO SNOW AS THE COLD ADVECTION ARRIVES.
IT WILL ALSO BECOME BREEZY TO WINDY SUNDAY AFTERNOON FROM WEST TO
EAST BEHIND THE TRACK OF THE LOW. STRONGEST WINDS 20-30 MPH WITH
GUSTS TO 35 MPH WILL SPREAD FROM THE SOUTHWEST SUNDAY AFTERNOON INTO
THE CENTRAL LATE AFTERNOON TO EARLY EVENING. HIGHS SUNDAY WILL
LIKELY BE REACHED IN THE MORNING NORTH TO EARLY AFTERNOON SOUTH WITH
TEMPERATURES FALLING MID TO LATE AFTERNOON EVERYWHERE.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 333 PM CST SAT DEC 6 2014
POST FRONTAL NORTHWEST WINDS OF 20 TO 30 MPH ALONG WITH ISOLATED TO
SCATTERED SNOW SHOWERS WILL DOMINATE SUNDAY NIGHT. THE ENTIRE SYSTEM
DEPARTS CENTRAL NORTH DAKOTA BY 12Z MONDAY WITH COLDER AIR REMAINING
IN PLACE FOR THE MORNING FOLLOWED BY WARM AIR ADVECTION MONDAY
AFTERNOON ESPECIALLY IN THE WEST. A PROGRESSIVE PATTERN CONTINUES
WITH A TRANSITORY RIDGE SHIFTING THROUGH MONDAY NIGHT FOLLOWED BY A
DRY SHORTWAVE TROUGH PASSING THROUGH TUESDAY. THEREAFTER...UPPER
RIDGING DOMINATES AND SHIFTS EAST BY MIDWEEK ALLOWING A SOUTHWEST
FLOW TO RETURN. HOWEVER NOTHING FORESEEN IN THE SOUTHWEST FLOW IN
TERMS OF SIGNIFICANT SHORTWAVES AT LEAST THROUGH SATURDAY PER
GFS/GEM GLOBAL/SUPERBLEND. HOWEVER THE LATEST ECMWF PUSHES A FAST
MOVING SHORTWAVE AND CONSEQUENTLY LIGHT PRECIPITATION/FAVORING RAIN
SHOWERS AT THIS POINT...ACROSS THE NORTH THURSDAY. HIGH TEMPERATURES
WILL WARM TO BETWEEN 35F AND 45F WEDNESDAY THROUGH FRIDAY...THEN A
BIT COOLER FOR SATURDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 620 PM CST SAT DEC 6 2014
VFR CONDITIONS ARE EXPECTED THROUGH THE OVERNIGHT HOURS. LCL -FZRA
MAY MOVE INTO NORTHWEST/WEST CENTRAL NORTH DAKOTA AFTER 06Z AND
PUSH TOWARDS NORTH CENTRAL NORTH DAKOTA THROUGH THE MORNING HOURS.
HAVE LEFT THIS OUT OF INDIVIDUAL TERMINAL FORECASTS FOR NOW GIVEN
THE LOW COVERAGE...BUT WILL MONITOR THROUGH THE EVENING. A
SURFACE LOW WILL PASS TO THE NORTH ON SUNDAY. WINDS WILL SWITCH
TOWARDS THE WEST/NORTHWEST AS SOME AREAS OF PRECIPITATION AGAIN
DEVELOP...MAINLY OVER THE NORTHWEST. -RA/-FZRA WILL BE
POSSIBLE....WITH A TRANSITION TOWARDS -SN AS COOLER AIR MOVES IN
FROM NORTHWEST TO SOUTHEAST. CIGS WILL DIMINISH TO MVFR LEVELS
FROM NORTHWEST TO SOUTHEAST STARTING LATE MORNING AND CONTINUING
THROUGH THE AFTERNOON.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JJS
SHORT TERM...TWH
LONG TERM...KS
AVIATION...JJS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1249 PM CST FRI DEC 5 2014
.UPDATE...
ISSUED AT 1248 PM CST FRI DEC 5 2014
HIGH PRESSURE OVER NORTHEAST MONTANA WILL CONTINUE TO SLIDE
SOUTHEAST ACROSS THE FORECAST AREA TODAY. LOW STRATUS AND FOG
CONTINUE ACROSS THE NORTHWEST BUT IS HAVING A HARD TIME MAKING IT
MUCH FARTHER SOUTH AND EAST. TEMPERATURES ACROSS THE NORTH HAVE
BEEN RISING SLOWLY...BUT IN THE SOUTH TEMPERATURES HAVE SHOT UP
QUICKLY. THUS HAVE BUMPED UP HIGHS A FEW DEGREES THIS AFTERNOON AS
WE WERE ALREADY SURPASSING FORECAST HIGHS. WITH NEUTRAL OR SLIGHT
COLD ADVECTION SOUTH WITH A NORTHERLY FLOW...DONT THINK
TEMPERATURES WILL RISE MUCH MORE...ESPECIALLY NORTH.
UPDATE ISSUED AT 947 AM CST FRI DEC 5 2014
AN AREA OF STRATUS CONTINUES TO DROP SOUTHEAST INTO NORTHWEST
NORTH DAKOTA. LOOKS LIKE THIS AREA SHOULD MOVE INTO KISN BETWEEN
16-17 UTC. THE EASTERN EDGE HAS DISSIPATED SO UNCERTAIN IF IT WILL
MAKE IT INTO KMOT THIS MORNING. OTHERWISE SHOULD BE A QUIET DAY.
HIGH LEVEL CLOUDS SPILLING OVER WESTERN RIDGE WILL BRING A
GENERAL INCREASE IN CLOUDS FROM WEST TO EAST LATER TODAY AND
TONIGHT.
UPDATE ISSUED AT 640 AM CST FRI DEC 5 2014
AN AREA OF STRATUS OVER SOUTHERN SASKATCHEWAN AND MANITOBA IS
MOVING SOUTH AROUND 30 MPH. THE STRATUS IS EXPECTED TO ENTER
NORTHWESTERN NORTH DAKOTA IN THE NEXT HOUR OR TWO...AND CONTINUE
ITS TRAJECTORY SOUTH OVER NORTHERN NORTH DAKOTA. THE MAIN
CHALLENGE WILL BE DETERMINING IF/WHEN THE CLOUD DECK BEGINS TO
DISSIPATE.
UPDATED THE FORECAST TO INCREASE CLOUD COVER NORTH THIS
MORNING...THEN DECREASED THE CLOUD COVER THIS AFTERNOON.
OTHERWISE...THE REMAINING WEATHER ELEMENTS ARE IN GOOD SHAPE. THE
UPDATED PRODUCTS HAVE BEEN SENT.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 254 AM CST FRI DEC 5 2014
QUIET AND COOL IS THE STORY FOR THE SHORT TERM.
MID LEVEL CLOUDS WILL CONTINUE TO DISSIPATE ACROSS SOUTHERN NORTH
DAKOTA THIS MORNING. THESE CLOUDS HAVE KEPT TEMPERATURES UP ALONG
AND SOUTH OF I-94. AS THE CLOUDS DISSIPATE AND MOVE OUT
TEMPERATURES SHOULD QUICKLY DROP OFF JUST BEFORE SUNRISE. ANOTHER
AREA OF CLOUDS ACROSS SASKATCHEWAN CONTINUES TO SLOWLY TRACK TO
THE SOUTHEAST...AIMING TOWARD NORTH CENTRAL NORTH DAKOTA. THE
RAP AND HRRR MODELS SHOW THIS AREA OF STRATUS DISSIPATING BEFORE
REACHING NORTH DAKOTA. THIS AREA OF CLOUDS WILL NEED TO BE
MONITORED THIS MORNING AS IT COULD IMPACT THE MINOT AIRPORT IF IT
HOLDS TOGETHER.
OTHERWISE...HIGH PRESSURE WILL BUILD IN FRIDAY AFTERNOON/EVENING.
THIS WILL BRING CLEAR SKIES AND COOL TEMPERATURES TO THE
REGION...WITH HIGHS IN THE TEENS NORTH TO 20S SOUTH.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 254 AM CST FRI DEC 5 2014
THE COMBINATION OF UPPER LEVEL RIDGING AND SOUTHERLY/SOUTHWESTERLY
BOUNDARY LAYER FLOW AHEAD OF A SHORTWAVE WILL LEAD TO DRY
CONDITIONS AND ABOVE NORMAL TEMPERATURES SATURDAY.
THE MEDIUM RANGE MODELS ARE IN FAIRLY GOOD AGREEMENT WITH RESPECT
TO THE TIMING AND POSITION OF THE AFOREMENTIONED SHORTWAVE AS IT
TRAVERSES NORTH DAKOTA SUNDAY/SUNDAY NIGHT. THE MAIN ENERGY IS
PROGGED TO REMAIN OVER THE NORTHERN COUNTIES...GENERATING A SLIGHT
CHANCE OF A WINTRY MIX NORTH SUNDAY AFTERNOON...THEN CHANGING OVER
TO SNOW EAST SUNDAY NIGHT AS THE SHORTWAVE USHERS IN MUCH COLDER
BOUNDARY LAYER TEMPERATURES. WINDY CONDITIONS ARE ALSO FORECAST TO
DEVELOP IN THE WAKE OF THE SHORTWAVE LATE SUNDAY AFTERNOON AND
NIGHT.
DRY CONDITIONS ARE THEN FORECAST AREAWIDE MONDAY AS HIGH PRESSURE
CRESTS ACROSS THE NORTHERN PLAINS.
FOR TUESDAY THROUGH THURSDAY...A BUILDING UPPER LEVEL RIDGE IS
FORECAST TO GENERATE DRY CONDITIONS AND A WARMING TREND TO 35F-45F
BOTH WEDNESDAY AND THURSDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1248 PM CST FRI DEC 5 2014
IFR CEILINGS CONTINUE AT KISN BUT IS HAVING A HARD TIME MAKING IT
MUCH FARTHER SOUTH AND EAST. HOWEVER...DO THINK WITH THE
INCREASING MOISTURE...THE THREAT OF FOG AND STRATUS WILL INCREASE
TONIGHT INTO SATURDAY MORNING. MESOSCALE MODELS ALSO INDICATE
INCREASING LOW LEVEL MOISTURE. WILL START OUT BY BRINGING SOME
SCATTERED STRATUS AND SOME MVFR VISIBILITIES LATER TONIGHT. WILL
NEED TO MONITOR AND UPDATE AS NEEDED.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...TWH
SHORT TERM...AJ
LONG TERM...TM
AVIATION...TWH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
947 AM CST FRI DEC 5 2014
.UPDATE...
ISSUED AT 947 AM CST FRI DEC 5 2014
AN AREA OF STRATUS CONTINUES TO DROP SOUTHEAST INTO NORTHWEST
NORTH DAKOTA. LOOKS LIKE THIS AREA SHOULD MOVE INTO KISN BETWEEN
16-17 UTC. THE EASTERN EDGE HAS DISSIPATED SO UNCERTAIN IF IT WILL
MAKE IT INTO KMOT THIS MORNING. OTHERWISE SHOULD BE A QUIET DAY.
HIGH LEVEL CLOUDS SPILLING OVER WESTERN RIDGE WILL BRING A
GENERAL INCREASE IN CLOUDS FROM WEST TO EAST LATER TODAY AND
TONIGHT.
UPDATE ISSUED AT 640 AM CST FRI DEC 5 2014
AN AREA OF STRATUS OVER SOUTHERN SASKATCHEWAN AND MANITOBA IS
MOVING SOUTH AROUND 30 MPH. THE STRATUS IS EXPECTED TO ENTER
NORTHWESTERN NORTH DAKOTA IN THE NEXT HOUR OR TWO...AND CONTINUE
ITS TRAJECTORY SOUTH OVER NORTHERN NORTH DAKOTA. THE MAIN
CHALLENGE WILL BE DETERMINING IF/WHEN THE CLOUD DECK BEGINS TO
DISSIPATE.
UPDATED THE FORECAST TO INCREASE CLOUD COVER NORTH THIS
MORNING...THEN DECREASED THE CLOUD COVER THIS AFTERNOON.
OTHERWISE...THE REMAINING WEATHER ELEMENTS ARE IN GOOD SHAPE. THE
UPDATED PRODUCTS HAVE BEEN SENT.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 254 AM CST FRI DEC 5 2014
QUIET AND COOL IS THE STORY FOR THE SHORT TERM.
MID LEVEL CLOUDS WILL CONTINUE TO DISSIPATE ACROSS SOUTHERN NORTH
DAKOTA THIS MORNING. THESE CLOUDS HAVE KEPT TEMPERATURES UP ALONG
AND SOUTH OF I-94. AS THE CLOUDS DISSIPATE AND MOVE OUT
TEMPERATURES SHOULD QUICKLY DROP OFF JUST BEFORE SUNRISE. ANOTHER
AREA OF CLOUDS ACROSS SASKATCHEWAN CONTINUES TO SLOWLY TRACK TO
THE SOUTHEAST...AIMING TOWARD NORTH CENTRAL NORTH DAKOTA. THE
RAP AND HRRR MODELS SHOW THIS AREA OF STRATUS DISSIPATING BEFORE
REACHING NORTH DAKOTA. THIS AREA OF CLOUDS WILL NEED TO BE
MONITORED THIS MORNING AS IT COULD IMPACT THE MINOT AIRPORT IF IT
HOLDS TOGETHER.
OTHERWISE...HIGH PRESSURE WILL BUILD IN FRIDAY AFTERNOON/EVENING.
THIS WILL BRING CLEAR SKIES AND COOL TEMPERATURES TO THE
REGION...WITH HIGHS IN THE TEENS NORTH TO 20S SOUTH.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 254 AM CST FRI DEC 5 2014
THE COMBINATION OF UPPER LEVEL RIDGING AND SOUTHERLY/SOUTHWESTERLY
BOUNDARY LAYER FLOW AHEAD OF A SHORTWAVE WILL LEAD TO DRY
CONDITIONS AND ABOVE NORMAL TEMPERATURES SATURDAY.
THE MEDIUM RANGE MODELS ARE IN FAIRLY GOOD AGREEMENT WITH RESPECT
TO THE TIMING AND POSITION OF THE AFOREMENTIONED SHORTWAVE AS IT
TRAVERSES NORTH DAKOTA SUNDAY/SUNDAY NIGHT. THE MAIN ENERGY IS
PROGGED TO REMAIN OVER THE NORTHERN COUNTIES...GENERATING A SLIGHT
CHANCE OF A WINTRY MIX NORTH SUNDAY AFTERNOON...THEN CHANGING OVER
TO SNOW EAST SUNDAY NIGHT AS THE SHORTWAVE USHERS IN MUCH COLDER
BOUNDARY LAYER TEMPERATURES. WINDY CONDITIONS ARE ALSO FORECAST TO
DEVELOP IN THE WAKE OF THE SHORTWAVE LATE SUNDAY AFTERNOON AND
NIGHT.
DRY CONDITIONS ARE THEN FORECAST AREAWIDE MONDAY AS HIGH PRESSURE
CRESTS ACROSS THE NORTHERN PLAINS.
FOR TUESDAY THROUGH THURSDAY...A BUILDING UPPER LEVEL RIDGE IS
FORECAST TO GENERATE DRY CONDITIONS AND A WARMING TREND TO 35F-45F
BOTH WEDNESDAY AND THURSDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 947 AM CST FRI DEC 5 2014
HAVE ADJUSTED TAFS TO DELAY STRATUS FOR ANOTHER HOUR. LOOKS LIKE
AN ARRIVAL BETWEEN 16-17 UTC AT KISN. THE EASTERN EDGE OF CLOUDS
HAS BEGUN TO DISSIPATE. WILL NEED TO TAKE ANOTHER LOOK TO POSSIBLY
DELAY OR EVEN REMOVE THE ARRIVAL AT KMOT. OTHERWISE EXPECT A
GENERAL INCREASE IN MID-HIGH LEVEL CLOUDS FROM WEST TO EAST LATER
TODAY THROUGH SATURDAY MORNING. LATEST NAM AND MESOSCALE MODELS
ARE INDICATING ABUNDANT MOISTURE OVER WESTERN NORTH DAKOTA ON THE
BACK SIDE OF THE SURFACE HIGH THAT MOVES THROUGH THE AREA TODAY.
WILL LOOK AT LATEST 12 UTC GUIDANCE TO SEE IF WE NEED TO INTRODUCE
MVFR CLOUDS IN THE WEST LATER TONIGHT INTO SATURDAY.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...TWH
SHORT TERM...AJ
LONG TERM...TM
AVIATION...TWH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
640 AM CST FRI DEC 5 2014
.UPDATE...
ISSUED AT 640 AM CST FRI DEC 5 2014
AN AREA OF STRATUS OVER SOUTHERN SASKATCHEWAN AND MANITOBA IS
MOVING SOUTH AROUND 30 MPH. THE STRATUS IS EXPECTED TO ENTER
NORTHWESTERN NORTH DAKOTA IN THE NEXT HOUR OR TWO...AND CONTINUE
ITS TRAJECTORY SOUTH OVER NORTHERN NORTH DAKOTA. THE MAIN
CHALLENGE WILL BE DETERMINING IF/WHEN THE CLOUD DECK BEGINS TO
DISSIPATE.
UPDATED THE FORECAST TO INCREASE CLOUD COVER NORTH THIS
MORNING...THEN DECREASED THE CLOUD COVER THIS AFTERNOON.
OTHERWISE...THE REMAINING WEATHER ELEMENTS ARE IN GOOD SHAPE. THE
UPDATED PRODUCTS HAVE BEEN SENT.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 254 AM CST FRI DEC 5 2014
QUIET AND COOL IS THE STORY FOR THE SHORT TERM.
MID LEVEL CLOUDS WILL CONTINUE TO DISSIPATE ACROSS SOUTHERN NORTH
DAKOTA THIS MORNING. THESE CLOUDS HAVE KEPT TEMPERATURES UP ALONG
AND SOUTH OF I-94. AS THE CLOUDS DISSIPATE AND MOVE OUT
TEMPERATURES SHOULD QUICKLY DROP OFF JUST BEFORE SUNRISE. ANOTHER
AREA OF CLOUDS ACROSS SASKATCHEWAN CONTINUES TO SLOWLY TRACK TO
THE SOUTHEAST...AIMING TOWARD NORTH CENTRAL NORTH DAKOTA. THE
RAP AND HRRR MODELS SHOW THIS AREA OF STRATUS DISSIPATING BEFORE
REACHING NORTH DAKOTA. THIS AREA OF CLOUDS WILL NEED TO BE
MONITORED THIS MORNING AS IT COULD IMPACT THE MINOT AIRPORT IF IT
HOLDS TOGETHER.
OTHERWISE...HIGH PRESSURE WILL BUILD IN FRIDAY AFTERNOON/EVENING.
THIS WILL BRING CLEAR SKIES AND COOL TEMPERATURES TO THE
REGION...WITH HIGHS IN THE TEENS NORTH TO 20S SOUTH.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 254 AM CST FRI DEC 5 2014
THE COMBINATION OF UPPER LEVEL RIDGING AND SOUTHERLY/SOUTHWESTERLY
BOUNDARY LAYER FLOW AHEAD OF A SHORTWAVE WILL LEAD TO DRY
CONDITIONS AND ABOVE NORMAL TEMPERATURES SATURDAY.
THE MEDIUM RANGE MODELS ARE IN FAIRLY GOOD AGREEMENT WITH RESPECT
TO THE TIMING AND POSITION OF THE AFOREMENTIONED SHORTWAVE AS IT
TRAVERSES NORTH DAKOTA SUNDAY/SUNDAY NIGHT. THE MAIN ENERGY IS
PROGGED TO REMAIN OVER THE NORTHERN COUNTIES...GENERATING A SLIGHT
CHANCE OF A WINTRY MIX NORTH SUNDAY AFTERNOON...THEN CHANGING OVER
TO SNOW EAST SUNDAY NIGHT AS THE SHORTWAVE USHERS IN MUCH COLDER
BOUNDARY LAYER TEMPERATURES. WINDY CONDITIONS ARE ALSO FORECAST TO
DEVELOP IN THE WAKE OF THE SHORTWAVE LATE SUNDAY AFTERNOON AND
NIGHT.
DRY CONDITIONS ARE THEN FORECAST AREAWIDE MONDAY AS HIGH PRESSURE
CRESTS ACROSS THE NORTHERN PLAINS.
FOR TUESDAY THROUGH THURSDAY...A BUILDING UPPER LEVEL RIDGE IS
FORECAST TO GENERATE DRY CONDITIONS AND A WARMING TREND TO 35F-45F
BOTH WEDNESDAY AND THURSDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 640 AM CST FRI DEC 5 2014
MVFR CIGS COULD IMPACT KISN-KMOT BETWEEN 15Z-20Z TODAY.
OTHERWISE...VFR CONDITIONS ARE EXPECTED OVER WESTERN AND CENTRAL
NORTH DAKOTA THROUGH THE TAF PERIOD.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...TM
SHORT TERM...AJ
LONG TERM...TM
AVIATION...AJ
AREA FORECAST DISCUSSION
NWS BISMARCK ND
254 AM CST FRI DEC 5 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 254 AM CST FRI DEC 5 2014
QUIET AND COOL IS THE STORY FOR THE SHORT TERM.
MID LEVEL CLOUDS WILL CONTINUE TO DISSIPATE ACROSS SOUTHERN NORTH
DAKOTA THIS MORNING. THESE CLOUDS HAVE KEPT TEMPERATURES UP ALONG
AND SOUTH OF I-94. AS THE CLOUDS DISSIPATE AND MOVE OUT
TEMPERATURES SHOULD QUICKLY DROP OFF JUST BEFORE SUNRISE. ANOTHER
AREA OF CLOUDS ACROSS SASKATCHEWAN CONTINUES TO SLOWLY TRACK TO
THE SOUTHEAST...AIMING TOWARD NORTH CENTRAL NORTH DAKOTA. THE
RAP AND HRRR MODELS SHOW THIS AREA OF STRATUS DISSIPATING BEFORE
REACHING NORTH DAKOTA. THIS AREA OF CLOUDS WILL NEED TO BE
MONITORED THIS MORNING AS IT COULD IMPACT THE MINOT AIRPORT IF IT
HOLDS TOGETHER.
OTHERWISE...HIGH PRESSURE WILL BUILD IN FRIDAY AFTERNOON/EVENING.
THIS WILL BRING CLEAR SKIES AND COOL TEMPERATURES TO THE
REGION...WITH HIGHS IN THE TEENS NORTH TO 20S SOUTH.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 254 AM CST FRI DEC 5 2014
THE COMBINATION OF UPPER LEVEL RIDGING AND SOUTHERLY/SOUTHWESTERLY
BOUNDARY LAYER FLOW AHEAD OF A SHORTWAVE WILL LEAD TO DRY
CONDITIONS AND ABOVE NORMAL TEMPERATURES SATURDAY.
THE MEDIUM RANGE MODELS ARE IN FAIRLY GOOD AGREEMENT WITH RESPECT
TO THE TIMING AND POSITION OF THE AFOREMENTIONED SHORTWAVE AS IT
TRAVERSES NORTH DAKOTA SUNDAY/SUNDAY NIGHT. THE MAIN ENERGY IS
PROGGED TO REMAIN OVER THE NORTHERN COUNTIES...GENERATING A SLIGHT
CHANCE OF A WINTRY MIX NORTH SUNDAY AFTERNOON...THEN CHANGING OVER
TO SNOW EAST SUNDAY NIGHT AS THE SHORTWAVE USHERS IN MUCH COLDER
BOUNDARY LAYER TEMPERATURES. WINDY CONDITIONS ARE ALSO FORECAST TO
DEVELOP IN THE WAKE OF THE SHORTWAVE LATE SUNDAY AFTERNOON AND
NIGHT.
DRY CONDITIONS ARE THEN FORECAST AREAWIDE MONDAY AS HIGH PRESSURE
CRESTS ACROSS THE NORTHERN PLAINS.
FOR TUESDAY THROUGH THURSDAY...A BUILDING UPPER LEVEL RIDGE IS
FORECAST TO GENERATE DRY CONDITIONS AND A WARMING TREND TO 35F-45F
BOTH WEDNESDAY AND THURSDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1228 AM CST FRI DEC 5 2014
VFR CONDITIONS ARE EXPECTED AT ALL TAF SITES THROUGH THE TAF
PERIOD. LIGHT AND VARIABLE WINDS WILL BECOME NORTHERLY EARLY THIS
MORNING.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...TM
AVIATION...AJ
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
1006 PM EST SAT DEC 6 2014
.SYNOPSIS...
LOW PRESSURE WAVE PASSES WITH COLDER AIR IN ITS WAKE TONIGHT.
HIGH PRESSURE SUNDAY. UPPER TROUGH MONDAY NIGHT/TUESDAY. COLDER
AIR TUESDAY NIGHT INTO WEDNESDAY.
&&
.NEAR TERM /THROUGH SUNDAY/...
10 PM UPDATE. NO SIGNIFICANT CHANGES.
PREVIOUS DISCUSSION...
AS OF 18Z THE FRONT HAS CLEARED CRW AND CKB WITH SURFACE LOW E OF
EKN. FRONT WILL CLEAR THE MOUNTAINS BY 21Z. AS THE FRONT
CROSSES...TEMPERATURE FALLS OF 7 TO 10 DEGREES CAN BE EXPECTED
WITH GRADUALLY LOWERING TEMPS THEREAFTER THROUGH THE EVENING. LOW
CIGS AND VSBY IN POST FRONTAL DZ CAN BE EXPECTED THRU THE
REMAINDER OF THE AFTERNOON...ALONG WITH GUSTY NW WINDS. WILL WATCH
-RA TO FILL BACK IN LATER THIS AFTERNOON AS THE UPPER LEVEL TROF
CROSSES. AREA WILL BEGIN TO DRY OUT WITH PASSAGE OF THE UPPER
LEVEL TROF...SAVE FOR SOME DZ HANGING ON ACROSS THE MOUNTAINS THIS
EVENING. ELECTED TO KEEP POSSIBILITY OF IT ENDING AS A LITTLE FRZ
DZ BUT NOT EXPECTING ANY IMPACTS.
WHAT WILL NOT CLEAR OUT THIS EVENING IS THE LOW STRATUS.
HOWEVER...DO EXPECT BASES TO LIFT A BIT TONIGHT. THINK SE OH WILL
SCT OUT DURING THE PREDAWN. HOWEVER...DEVELOPING SUBSIDENCE
INVERSION BENEATH THIS LINGERING MOISTURE WILL MAKE IT VERY
DIFFICULT FOR STRATUS TO BREAK UP E OF THE OH RIVER OVERNIGHT. WITH WEAK
CAA BENEATH THE INVERSION AND LOW LEVEL WINDS BECOMING MORE
NE...FELT IT NECESSARY TO HOLD THE STRATUS IN ALONG THE
CLIMATOLOGICAL FAVORED AREAS IN THIS SETUP....IE THE C LOWLANDS
AND COAL FIELDS THRU THE MORNING HOURS. CLOUDS WILL GRADUALLY SCT
OUT FROM NE TO SW...WITH AREAS ALONG AND S OF I64 CORRIDOR THE
LAST TO LOSE THE STRATUS...POSSIBLY HOLDING ON UNTIL LATE
AFTERNOON.
FOR TEMPS...USED A BLEND OF LAMP AND HRRR FOR TEMPS TONIGHT. FOR
SUNDAY...USED MET AS A BASE WHICH BETTER REFLECTED EXPECTED COOLER
READINGS ALONG AND ESPECIALLY S OF I64 CORRIDOR DUE TO CLOUDS.
FURTHER N...FELT LOCAL MOS WAS THE WAY TO GO WHERE READINGS SHOULD
REACH INTO THE MID OR UPPER 40S.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
STRONG MID LEVEL RIDGING AND HIGH PRESSURE INFLUENCES FROM EASTERN
CANADA DOMINATE SUNDAY...BUT SUNSHINE STILL LIMITED TO THE MORNING
HOURS WITH CIRRUS AHEAD OF THE UPPER LEVEL TROUGH DIGGING IN OVER
THE WESTERN GREAT LAKES. MODELS NOW SETTLING ON THE TROUGH AXIS
HOLDING THE DEVELOPING COASTAL SYSTEM OFFSHORE AND MAINLY AWAY FROM
OUR EASTERN MOST RIDGES...BUT WILL STILL ENTERTAIN SOME LOW END POPS
FOR THE FAR EASTERN PORTIONS OF RAND/POCA COUNTIES. SOME ICING IS
POSSIBLE IN THE SOUTHEAST UPSLOPE AREAS.
HAVE THE TRANSITION TO SNOW FOR THE LOWLAND UPSLOPE AREAS FROM RAIN
TO SNOW A BIT SLOWER...AND JUST BEGINNING BY THE END OF THE SHORT
TERM FORECAST AT 00Z WEDNESDAY. 925MB TEMPERATURES GO BELOW 0C JUST
AFTER 21Z TUESDAY FOR THE MOUNTAINS...MAKING THE 18Z TO 00Z PERIOD
THE RAIN/SNOW TRANSITION TIMES FOR THE MOUNTAINOUS AREAS. LOWLANDS
WILL TRANSITION TO SNOW LIKELY IN THE BEGINNING FEW HOURS OF THE
LONG TERM.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
USED A BLEND OF THE GFS...GEFS MEAN...ECMWF...ECMWF MEAN...AND
CONTINUITY WITH THE PREVIOUS FORECAST. THIS WOULD HAVE WRAP AROUND
MOISTURE OVER THE REGION FOR TUESDAY NIGHT INTO WEDNESDAY. 850 MB
TEMPERATURES ARE MARGINAL FOR UPSLOPE SNOW...SO COULD SEE DRIZZLE
INSTEAD OF SNOW IN MANY AREAS. A HIGH PRESSURE SYSTEM THEN MOVES IN
FOR THE END OF THE WORK WEEK AND INTO THE WEEKEND...ALLOWING
TEMPERATURES TO MODERATE SOME.
&&
.AVIATION /03Z SUNDAY THROUGH THURSDAY/...
03Z SUNDAY THRU 00Z MONDAY...
SOME DRIZZLE/FREEZING DRIZZLE LINGERING IN THE HIGHER ELEVATIONS OF
THE MOUNTAINS TIL AROUND 05Z. PREVAILING MVFR CEILINGS FROM CKB-CRW
WESTWARD...AND BY 06Z BELOW 2500 FEET IN THE MOUNTAINS...WITH
LINGERING IFR CEILINGS ABOVE 2500 FEET. THESE CONDITIONS WILL
GENERALLY CONTINUE REMAINDER OF TONIGHT. GUSTY NORTH WINDS 10 TO 20
MPH WILL SLOWLY DIMINISH OVERNIGHT.
AFTER 12Z...RAPID CLEARING FROM NORTH TO SOUTH AS DRIER AIR WORKS
SOUTHWARD WITH CANADIAN HIGH PRESSURE. BECOMING VFR SCT CLOUDS BY
15Z AT PKB...CKB AND EKN...AND BY 18Z AT HTS...CRW AND BKW. ONLY THE
SOUTHERN COAL FIELDS AND SOUTHERN MOUNTAINS RETAIN MVFR CEILINGS
TIL AROUND 21Z. THEREAFTER...VFR MOSTLY CLEAR. ENE WINDS AROUND 8 TO
12 KTS.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 00Z MONDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATE SCENARIOS: TIMING AND EXTENT OF IFR CONDITIONS MAY VARY.
TIMING ERADICATION OF LOW STRATUS MAY VARY...POSSIBLY OCCURRING
SOONER THAN CURRENTLY FORECAST.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE SUN 12/07/14
UTC 1HRLY 02 03 04 05 06 07 08 09 10 11 12 13
EST 1HRLY 21 22 23 00 01 02 03 04 05 06 07 08
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H H H H M H H H M
EKN CONSISTENCY H H H H M H H H H M M M
PKB CONSISTENCY H H H H H H H H H M M M
CKB CONSISTENCY H H H H H H H H H H H M
AFTER 00Z MONDAY...
IFR POSSIBLE IN RAIN/SNOW MONDAY NIGHT INTO WEDNESDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...RPY/JMV/30/26
NEAR TERM...JMV/30
SHORT TERM...26
LONG TERM...RPY
AVIATION...JMV
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
636 PM EST SAT DEC 6 2014
.SYNOPSIS...
LOW PRESSURE WAVE PASSES WITH COLDER AIR IN ITS WAKE TONIGHT.
HIGH PRESSURE SUNDAY. UPPER TROUGH MONDAY NIGHT/TUESDAY. COLDER
AIR TUESDAY NIGHT INTO WEDNESDAY.
&&
.NEAR TERM /THROUGH SUNDAY/...
630 PM UPDATE. NO SIGNIFICANT CHANGES.
PREVIOUS DISCUSSION...
AS OF 18Z THE FRONT HAS CLEARED CRW AND CKB WITH SURFACE LOW E OF
EKN. FRONT WILL CLEAR THE MOUNTAINS BY 21Z. AS THE FRONT
CROSSES...TEMPERATURE FALLS OF 7 TO 10 DEGREES CAN BE EXPECTED
WITH GRADUALLY LOWERING TEMPS THEREAFTER THROUGH THE EVENING. LOW
CIGS AND VSBY IN POST FRONTAL DZ CAN BE EXPECTED THRU THE
REMAINDER OF THE AFTERNOON...ALONG WITH GUSTY NW WINDS. WILL WATCH
-RA TO FILL BACK IN LATER THIS AFTERNOON AS THE UPPER LEVEL TROF
CROSSES. AREA WILL BEGIN TO DRY OUT WITH PASSAGE OF THE UPPER
LEVEL TROF...SAVE FOR SOME DZ HANGING ON ACROSS THE MOUNTAINS THIS
EVENING. ELECTED TO KEEP POSSIBILITY OF IT ENDING AS A LITTLE FRZ
DZ BUT NOT EXPECTING ANY IMPACTS.
WHAT WILL NOT CLEAR OUT THIS EVENING IS THE LOW STRATUS.
HOWEVER...DO EXPECT BASES TO LIFT A BIT TONIGHT. THINK SE OH WILL
SCT OUT DURING THE PREDAWN. HOWEVER...DEVELOPING SUBSIDENCE
INVERSION BENEATH THIS LINGERING MOISTURE WILL MAKE IT VERY
DIFFICULT FOR STRATUS TO BREAK UP E OF THE OH RIVER OVERNIGHT. WITH WEAK
CAA BENEATH THE INVERSION AND LOW LEVEL WINDS BECOMING MORE
NE...FELT IT NECESSARY TO HOLD THE STRATUS IN ALONG THE
CLIMATOLOGICAL FAVORED AREAS IN THIS SETUP....IE THE C LOWLANDS
AND COAL FIELDS THRU THE MORNING HOURS. CLOUDS WILL GRADUALLY SCT
OUT FROM NE TO SW...WITH AREAS ALONG AND S OF I64 CORRIDOR THE
LAST TO LOSE THE STRATUS...POSSIBLY HOLDING ON UNTIL LATE
AFTERNOON.
FOR TEMPS...USED A BLEND OF LAMP AND HRRR FOR TEMPS TONIGHT. FOR
SUNDAY...USED MET AS A BASE WHICH BETTER REFLECTED EXPECTED COOLER
READINGS ALONG AND ESPECIALLY S OF I64 CORRIDOR DUE TO CLOUDS.
FURTHER N...FELT LOCAL MOS WAS THE WAY TO GO WHERE READINGS SHOULD
REACH INTO THE MID OR UPPER 40S.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
STRONG MID LEVEL RIDGING AND HIGH PRESSURE INFLUENCES FROM EASTERN
CANADA DOMINATE SUNDAY...BUT SUNSHINE STILL LIMITED TO THE MORNING
HOURS WITH CIRRUS AHEAD OF THE UPPER LEVEL TROUGH DIGGING IN OVER
THE WESTERN GREAT LAKES. MODELS NOW SETTLING ON THE TROUGH AXIS
HOLDING THE DEVELOPING COASTAL SYSTEM OFFSHORE AND MAINLY AWAY FROM
OUR EASTERN MOST RIDGES...BUT WILL STILL ENTERTAIN SOME LOW END POPS
FOR THE FAR EASTERN PORTIONS OF RAND/POCA COUNTIES. SOME ICING IS
POSSIBLE IN THE SOUTHEAST UPSLOPE AREAS.
HAVE THE TRANSITION TO SNOW FOR THE LOWLAND UPSLOPE AREAS FROM RAIN
TO SNOW A BIT SLOWER...AND JUST BEGINNING BY THE END OF THE SHORT
TERM FORECAST AT 00Z WEDNESDAY. 925MB TEMPERATURES GO BELOW 0C JUST
AFTER 21Z TUESDAY FOR THE MOUNTAINS...MAKING THE 18Z TO 00Z PERIOD
THE RAIN/SNOW TRANSITION TIMES FOR THE MOUNTAINOUS AREAS. LOWLANDS
WILL TRANSITION TO SNOW LIKELY IN THE BEGINNING FEW HOURS OF THE
LONG TERM.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
USED A BLEND OF THE GFS...GEFS MEAN...ECMWF...ECMWF MEAN...AND
CONTINUITY WITH THE PREVIOUS FORECAST. THIS WOULD HAVE WRAP AROUND
MOISTURE OVER THE REGION FOR TUESDAY NIGHT INTO WEDNESDAY. 850 MB
TEMPERATURES ARE MARGINAL FOR UPSLOPE SNOW...SO COULD SEE DRIZZLE
INSTEAD OF SNOW IN MANY AREAS. A HIGH PRESSURE SYSTEM THEN MOVES IN
FOR THE END OF THE WORK WEEK AND INTO THE WEEKEND...ALLOWING
TEMPERATURES TO MODERATE SOME.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
00Z SUNDAY THRU 00Z MONDAY...
COLD FRONT HAS SHIFTED EAST OF THE MOUNTAINS AT 23Z. POST FRONTAL
LIGHT RAIN AND FOG WILL MOVE OUT OF THE EASTERN LOW LANDS BY
02Z...WITH SOME DRIZZLE/FREEZING DRIZZLE LINGERING IN THE HIGHER
ELEVATIONS OF THE MOUNTAINS TIL AROUND 04Z. BY 02Z LOOK FOR
IMPROVEMENT TO PREVAILING MVFR CEILINGS FROM CKB-CRW WESTWARD...AND
BY 05Z BELOW 2500 FEET IN THE MOUNTAINS...WITH LINGER IFR CEILINGS
ABOVE 2500 FEET. THESE CONDITIONS WILL GENERALLY CONTINUE REMAINDER
OF TONIGHT. GUSTY NORTH WINDS 10 TO 20 MPH WILL SLOWLY DIMINISH
OVERNIGHT.
AFTER 12Z...RAPID CLEARING FROM NORTH TO SOUTH AS DRIER AIR WORKS
SOUTHWARD WITH CANADIAN HIGH PRESSURE. BECOMING VFR SCT CLOUDS BY
15Z AT PKB...CKB AND EKN...AND BY 18Z AT HTS...CRW AND BKW. ONLY THE
SOUTHERN COAL FIELDS AND SOUTHERN MOUNTAINS RETAIN MVFR CEILINGS
TIL AROUND 21Z. THEREAFTER...VFR MOSTLY CLEAR. ENE WINDS AROUND 8 TO
12 KTS.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 00Z MONDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATE SCENARIOS: TIMING AND EXTENT OF IFR CONDITIONS MAY VARY.
TIMING ERADICATION OF LOW STRATUS MAY VARY...POSSIBLY OCCURRING
SOONER THAN CURRENTLY FORECAST.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE SUN
UTC 1HRLY 00 01 02 03 04 05 06 07 08 09 10 11
EST 1HRLY 19 20 21 22 23 00 01 02 03 04 05 06
CRW CONSISTENCY M M H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H H M M H H M H H
EKN CONSISTENCY H H H M H H M M H M M M
PKB CONSISTENCY H H H H H H H H H H H M
CKB CONSISTENCY M H H H H H H H H H H H
AFTER 00Z MONDAY...
IFR POSSIBLE IN RAIN/SNOW MONDAY NIGHT INTO WEDNESDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...RPY/JMV/30/26
NEAR TERM...JMV/30
SHORT TERM...26
LONG TERM...RPY
AVIATION...JMV
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
1233 AM EST FRI DEC 5 2014
.SYNOPSIS...
SERIES OF LOW PRESSURE WAVES CROSS INTO THE WEEKEND. HIGH PRESSURE
SUNDAY. COLD FRONT EARLY NEXT WEEK MAY BE FOLLOWED A BY LONGER
PERIOD OF HIGH PRESSURE.
&&
.NEAR TERM /THROUGH TODAY/...
930 PM UPDATE. NOT MUCH CHANGE GIVEN THE CONTINUED WARM ADVECTION
AND UPPER DISTURBANCES KEEPING THE THREAT OF PRECIP. STILL WILL KEEP
FRZ RAIN ADVISORY FOR POCAHONTAS COUNTY OVERNIGHT FOR MARGINAL ICING
EVENT.
PREVIOUS DISCUSSION...
PRECIP EXPANDING NE A BIT QUICKER THAN PREVIOUS FORECAST. STILL A
SIGNIFICANT DRY LAYER IN THE LOWER LAYERS TO OVERCOME...BUT
IT WONT TAKE LONG FOR THIS TO ERODE ONCE THE PRECIP MOVES IN.
EXCEPTION BEING ACROSS SE OH AND N WV WHERE THE DRY LAYER IS A BIT
MORE ROBUST. USED LATEST HRRR FOR TIMING OF HIGH POPS IN THRU THIS
AFTERNOON AND EVENING. ALSO INSERTED A BRIEF PERIOD OF SLEET MIXING IN ON
THE LEADING EDGE ACROSS NE KY/ W WV/ AND SE OH. THIS MIX CAN BE
EXPECTED IN THE N MOUNTAINS AS WELL.
ONCE THIS WAVE MOVES BY...CWA LEFT WITH WARM FRONT THIS EVENING WITH
SHRA REGIME MAINLY N HALF OF CWA. WILL WATCH FOR A SURFACE LOW TO
ORGANIZE OVER THE TN VALLEY WITH A WARM FRONT APPENDAGE DEVELOPING
INTO AREA LATE TONIGHT. THIS WILL INCREASE THE COVERAGE OF PRECIP
HEADING INTO FRIDAY AS THE WARM FRONT SLOWLY SHIFTS INTO SE OH.
THERE MAY BE AN EXTENDED LULL IN PRECIP ACROSS SW VA AND SE WV
FRIDAY WITH THESE AREAS IN WARM SECTOR.
AFTER INTERROGATING HI RES MODELS AND SREF PROBS...ELECTED NOT TO
EXPAND THE FRZ RA ADVISORY TO RANDOLPH. ASIDE FROM A BRIEF MIX
LATER THIS AFTERNOON...EXPECT BULK OF PRECIP TONIGHT TO FALL AS
RAIN. THERE COULD BE A LITTLE FRZ RA ACROSS FAR EASTERN RANDOLPH
BUT DEFINITELY NOT A COUNTY WIDE AVG. IN FACT...THERE IS CONCERN
THAT TEMPS MAY WARM ENOUGH TONIGHT FOR RAIN EVEN OVER POCAHONTAS
COUNTY. HI RES NAM IS BY FAR COOLEST OF THE MODELS...KEEPING A SUB
FRZ THIN LAYER AROUND H9. ELEVATIONS ABOVE 3 KFT SHOULD GET INTO
WARM LAYER SUCH THAT RISING TEMPS ARE EXPECTED TONIGHT. IT SHOULD
BE QUITE MILD TOMORROW IN WARM SECTOR WHERE MID TO UPPER 50S WERE
CODED UP ACROSS SW VA UP TO I64. DOWNSLOPING COMPONENT PROBABLY
ALSO SENDS EKN INTO THE LOW 50S.
&&
.SHORT TERM /TONIGHT THROUGH SUNDAY/...
VERY FEW CHANGES TO THE SHORT TERM FORECAST. KEEP THE HIGH POPS
GOING THROUGH THE SATURDAY PERIOD...DECREASING INTO SATURDAY NIGHT
WITH THE PASSAGE OF THE SURFACE LOW AND ACCOMPANYING UPPER LEVEL
TROUGH AXIS. EXPECTING A BATCH OF HEAVIER RAIN TO COME THROUGH IN
THE 09Z SATURDAY TIME FRAME WITH 850MB THETA E CONVERGENCE
PEAKING. AFTER ALL IS SAID AND DONE...1-1.5 INCHES OF RAIN IS NOT
OUT OF THE QUESTION BY SATURDAY NIGHT WHEN THE SYSTEM EXITS.
CLEARING SHOULD OCCUR QUICKLY SUNDAY AS THE FLOW WILL NOT GO TO
ITS TYPICAL NORTHWEST TRAJECTORY. LOOKING AT A NORTH NORTHEASTERLY
LOW LEVEL FLOW AND QUICK DRYING ALOFT...SO SHOULD SEE SOME SUN ON
SUNDAY. CIRRUS FROM THE NEXT SYSTEM FOR THE LONG TERM PERIOD WILL
BE ON ITS WAY IN QUICKLY AS IT ORGANIZES TO THE WEST.
AIRMASS BEHIND THE LOW PRESSURE SYSTEM WILL DROP HIGH TEMPERATURES
BACK INTO THE 40S FOR THE LOWLANDS...30S FOR THE MOUNTAINS.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
MODELS INDICATE A HIGH PRESSURE MOVING OVER NEW ENGLAND...EXTENDING
SOUTHWEST INTO WV SUNDAY NIGHT. ALTHOUGH A COLD AIR MASS WILL BE IN
PLACE...THIS PATTERN WOULD BRING EAST TO SOUTHEAST FLOW...CAPABLE TO
PRODUCE DOWNSLOPING WARMING ACROSS THE LOWLANDS SUNDAY NIGHT.
INCREASED FEW DEGREES FROM HPC GUIDANCE ACCORDINGLY.
FOR MONDAY...BUFKIT SOUNDINGS SHOW DRY AIR ALOFT WITH LIMITED
MOISTURE IN THE VERY LOW LEVELS WHILE A H500 WEAK SHORTWAVE CROSSES
THE AREA. KEPT LOW CHANCE POPS WITH THIS FEATURE...MORE ALONG THE
GFS SOLUTION. THE ECMWF BRINGS STRONG COLD AIR ADVECTION FOR THE
SAME TIME PERIOD WITH SUCH A WEAK WAVE. BELIEVE ECMWF IS OVERDOING
CAA SO PREFERRED THE GFS.
BY MONDAY NIGHT FLOW IN THE LOW LEVELS TURN NORTHWEST WITH SOME CAA
FROM BOTH MODELS. FIGURE A GOOD SET UP FOR UPSLOPE PCPN. THE GFS
BRINGS THE 0C LEVEL AROUND THE NORTHEAST MOUNTAINS WHILE IN THE
ECMWF...THE 0C LINE GOES WAY SOUTH OF THE AREA. WENT WITH A BLEND
SOLUTION EXPECTING CHANCE POPS WITH FEW SNOW SHOWERS OR MIX PCPN
OVER THE MOST FAVORABLE UPSLOPE AREAS...AND RAIN ELSEWHERE. PCPN IS
EXPECTED TO TAMPER OFF ON TUESDAY KEEPING CHANCE POPS OVER THE
EASTERN MOUNTAINS ESPECIALLY WITH THE UPSLOPE COMPONENT AND DRY
WEATHER SPREADING FROM SOUTHEAST OH...EAST.
DRY WEATHER EXPECTED THROUGH THE REST OF THE PERIOD AS A HIGH
PRESSURE BUILDS IN.
WENT CLOSE TO HPC TEMPERATURES THROUGH THE PERIOD.
&&
.AVIATION /05Z FRIDAY THROUGH TUESDAY/...
LOTS OF LOW LEVEL MOISTURE IN THE AREA...AND A WARM FRONT WITH
SEVERAL SEPARATE WAVES OF LOW PRESSURE...WILL KEEP IFR OR MVFR
CIGS IN PLACE THROUGH MUCH IF NOT ALL OF THE TAF PERIOD. ALSO WILL
HAVE PERIODS OF DRIZZLE...FOG...AND LIGHT RAIN PRODUCING MVFR
VISIBILITIES AS WELL. SURFACE WINDS ARE CURRENTLY N/NE...AND WILL
TURN MORE SOUTHERLY ON FRIDAY AS THE WARM FRONT DRIFTS NORTHWARD.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z SATURDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATE SCENARIOS: TIMING AND EXTENT OF IFR CONDITIONS IN RAIN AND
DRIZZLE MAY VARY OVERNIGHT TONIGHT...AND IN ANY IMPROVEMENT
FRIDAY. IF THERE IS ENOUGH DOWNSLOPE COMPONENT TO THE WIND...COULD
SEE HIGHER CEILINGS IN TYPICAL DOWNSLOPE IMPACTED LOCATIONS LIKE
EKN...CKB AND MAYBE CRW.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE FRI 12/05/14
UTC 1HRLY 06 07 08 09 10 11 12 13 14 15 16 17
EST 1HRLY 01 02 03 04 05 06 07 08 09 10 11 12
CRW CONSISTENCY M M M M M M M H H H H H
HTS CONSISTENCY M M M M H H H H H H H H
BKW CONSISTENCY H H H H H H M M M M H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H M M M M M M H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 06Z SATURDAY...
IFR POSSIBLE FRIDAY NIGHT INTO THE WEEKEND IN RAIN.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...FREEZING RAIN ADVISORY UNTIL 11 AM EST THIS MORNING FOR WVZ046.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...ARJ/JMV/30/26
NEAR TERM...JMV/30
SHORT TERM...26
LONG TERM...ARJ
AVIATION...MZ
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
947 AM EST FRI DEC 5 2014
.SYNOPSIS...
MILD AND MOIST AIR RIDING NORTHEAST AND OVER A SHALLOW COLD
AIRMASS STUCK IN PLACE ACROSS PENNSYLVANIA WILL BRING PERIODS OF
LIGHT FREEZING RAIN AND SLEET TODAY...ESPECIALLY DURING THE
AFTERNOON HOURS. MUCH OF THE PRECIPITATION LATE TODAY WILL CHANGE
TO PLAIN RAIN...HOWEVER POCKETS OF FREEZING RAIN ARE STILL LIKELY
INTO EARLY TONIGHT ACROSS THE RIDGES OF CENTRAL PENNSYLVANIA.
A SECOND SURGE OF PRECIPITATION IN THE FORM OF PLAIN RAIN WILL
IMPACT THE REGION ON SATURDAY...FOLLOWED BY DRY WEATHER FOR
SUNDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SURFACE WET BULB ZEROS LIFTING NORTHWARD AT A SNAILS PACE THIS
MORNING. POCKETS OF FREEZING RAIN AND SOME SLEET PRESENTLY
CROSSING THE CENTRAL AND SOUTH CENTRAL MOUNTAINS. DEWPOINTS IN THE
LOWER TO MIDDLE 20S WILL ENSURE THE POTENTIAL FOR FREEZING RAIN
PERSISTS WELL INTO THIS AFTERNOON IN THE ADVISORY AREAS. MAY NEED
TO HOLD ONTO ADVISORIES FOR NORTHERN PORTIONS OF THE LAURELS
THROUGH MID TO LATE AFTERNOON AS ARW AND HRRR INDICATE POCKETS OF
MAINLY HIGHER ELEVATION FREEZING RAIN LIKELY CONTINUING THERE.
INCREASING BOUNDARY LAYER MOISTURE CONVERGENCE THROUGHOUT THE DAY
WILL PRODUCE INCREASING COVERAGE OF PRECIPITATION...BUT RATES AND
AMOUNTS WILL REMAIN LIGHT. CURRENT FORECAST IN GOOD SHAPE FOR LATE
THIS MORNING AND THIS AFTERNOON BEYOND NEAR TERM TEMP WEAKS.
ACROSS THE FAR NORTH...IT WILL BE MOST PROBLEMATIC TO MIX OUT THE
SHALLOW COLD AIR. GIVEN THE VERY COLD AIR IN THE TEENS ACROSS THAT
REGION EARLY TODAY /AND ANY SIGNIF INSOLATION BEING CUT-OFF BY THE
THICKENING CLOUDS THIS MORNING/ IT MAY NOT REACH FREEZING UNTIL
AFTER 00Z SAT.
WARMER AIR SHOULD WIN OUT IN THE EARLY AFTN IN THE SW/CENT MTNS
AND BY EVENING IN THE NRN TIER - WHERE IT COULD BE
HEAVIEST/THICKEST AS IT LINGERS THERE THE LONGEST TIME.
THE FAR SOUTHEAST CONTINUES TO REMAINS OUTSIDE OF THE ADVISORY
AREA...BUT COULD SEE SOME ICE PELLETS AT THE START...OR PERHAPS
VERY SPOTTY FREEZING RAIN UNTIL AROUND 14Z. AT THIS TIME...THE
CHANCES OF FZRA ARE STILL TOO LOW TO EXPAND THE ADVISORY THERE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SATURDAY/...
WAA AHEAD OF APPROACHING SFC LOW SHOULD PUSH TEMPS ABV FREEZING
EVERYWHERE LATER TONIGHT INTO SAT AS HEAVIEST RAIN OVERSPREADS
THE REGION W/PASSAGE OF LL JET AND PLUME OF ANOMALOUS PWATS. HAVE
INCREASED POPS UPWARDS BASED ON LATEST ENSEMBLE DATA...WHICH
SUPPORTS STORM TOTAL RAIN AMTS BY SAT NIGHT CLOSE TO 1 INCH OVER
THE NORTHERN AND EASTERN HALF OF CENTRAL PA. SLIGHTLY LESS ACROSS
THE LOWER CENTRAL PORTIONS OF THE STATE. THE LATEST GEFS AND
ENSEMBLE EC RUNS SHOW AN INCREASE IN PRECIPITATION AS THE LOW
MOVES OFF SHORE.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
BUILDING MODEL CONSENSUS FOR A DRY SUNDAY. RIDGING AT SFC AND
ALOFT IS BUILDING IN BEHIND THE SHORTWAVE. THE 12Z ECENS AND GEFS
REMAIN IN AGREEMENT IN KEEPING COASTAL DEVELOPMENT OFFSHORE EARLY
NEXT WEEK. HOWEVER...THE MODELS DIVERGE BY TUESDAY AND AS NORTHERN
STREAM SHORTWAVE DIVES SE INTO THE REGION...THE EC RETROGRADES THE
LOW OFF THE COAST AND ITS RESULTANT MOISTURE AND THE SHORTWAVE
DEEPENS AND MOVES NORTHEASTWARD. THIS WOULD BRING ANOTHER
SIGNIFICANT RAIN TO THE EASTERN HALF OF PA. THE GFS IS MUCH MORE
MILDER...WITH MAINLY ZONAL FLOW WITH A SHALLOW SHORTWAVE AND ONLY
A SLIGHT CHANCE OF RAIN/SNOW SHOWERS TUESDAY. DUE TO THIS
DICHOTOMY HAVE ONLY LEFT SLIGHT TO CHANCE POPS IN...WITH HIGHER
CHANCE IN THE EAST DUE TO THE HIGHER PROBABILITIES. CHANCE
RELATIVELY HIGH CONFIDENCE IN DRY WEATHER BY WED...WHEN BOTH ECENS
AND GEFS SHOW A LARGE SFC HIGH BUILDING IN FROM THE GRT LKS. NO
COLD WX IN SIGHT. TEMPS SLIGHTLY ABV NORMAL THE FIRST HALF OF NEXT
WEEK MAY BECOME SIGNIFICANTLY ABV NORMAL BY LATE NEXT WEEK...AS
ALL MED RANGE GUIDANCE SHOWING BROAD ZONAL FLOW ACROSS THE CONUS.
&&
.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
IN ADVANCE OF A MID/UPPER TROUGH AND SFC LOW EJECTING EWD FROM
THE SOUTH-CENTRAL PLAINS...MOISTURE OVERRUNNING RETREATING SFC
HIGH AND ASSOCD WEDGE OF SHALLOW COLD AIR NEAR THE GROUND OVER
INTERIOR PA WILL LEAD TO POCKETS OF MIXED WINTRY PCPN EARLY TODAY
ACROSS THE AIRSPACE. REGIONAL RADAR TRENDS SHOW EXPANDING AREA OF
RETURNS MOVG ENEWD FROM NRN WV INTO SWRN PA. CIGS ARE LOWERING ON
SCHEDULE...GRADUALLY DROPPING TO MVFR AND IFR BY TONIGHT. BLYR
TEMPS SHOULD SLOWLY WARM TO CHANGE ANY LINGERING -FZRA TO A COLD
MODERATE RAIN BY LATE TONIGHT...WHICH WILL CONTINUE THROUGH THE
DAY ON SATURDAY. TEMPS MAY BE COLD ENOUGH TO SUPPORT A TRANSITION
BACK TO SNOW ON THE NW SIDE OF LOW TRACKING FROM WV THROUGH THE
DELMARVA LATE SAT INTO SAT NGT.
OUTLOOK...
SAT...MVFR/IFR IN RAIN. SNOW POSSIBLE N/W AND GUSTY NNW WINDS SAT
NGT.
SUN...PCPN ENDING EAST EARLY...BECOMING VFR.
MON...MAINLY VFR.
TUE...VFR/MVFR WITH CHC OF RAIN/SNOW.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 5 PM EST THIS AFTERNOON FOR
PAZ004>006-010>012-037-041-042.
WINTER WEATHER ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
PAZ017>019-024>028-033>035-045-046-049-050.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...DEVOIR/LAMBERT
SHORT TERM...LAMBERT
LONG TERM...FITZGERALD/CERU
AVIATION...STEINBUGL
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
703 AM EST FRI DEC 5 2014
.SYNOPSIS...
MILD AND MOIST AIR RIDING NORTHEAST AND OVER A SHALLOW COLD
AIRMASS STUCK IN PLACE ACROSS PENNSYLVANIA WILL BRING PERIODS OF
LIGHT FREEZING RAIN AND SLEET TODAY...ESPECIALLY DURING THE
AFTERNOON HOURS. MUCH OF THE PRECIPITATION LATE TODAY WILL CHANGE
TO PLAIN RAIN...HOWEVER POCKETS OF FREEZING RAIN ARE STILL LIKELY
INTO EARLY TONIGHT ACROSS THE RIDGES OF CENTRAL PENNSYLVANIA.
A SECOND SURGE OF PRECIPITATION IN THE FORM OF PLAIN RAIN WILL
IMPACT THE REGION ON SATURDAY...FOLLOWED BY DRY WEATHER FOR
SUNDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE MAINLY CLEAR SKIES EARLIER DURING THE OVERNIGHT LED TO AREAS
OF STRONG RADIATIONAL COOLING. 10Z TEMPS RANGE FROM NEAR 20F
ACROSS OUR FAR NE ZONES...TO THE MID AND UPPER 20S THROUGHOUT MUCH
OF THE CENTRAL VALLEYS AND MIDDLE SUSQUEHANNA VALLEY. TEMPS WERE
HOVERING AROUND 30-32F ACROSS THE SW NEAR KJST AND KAOO.
SKIES HAVE BECOME OVERCAST ACROSS MUCH OF THE REGION THIS MORNING
IN THE FORM OF A MULTI-LAYERED CLOUD DECK. AN ARC OF SHOWERY LIGHT
PRECIP WAS HEADING ACROSS THE LAUREL HIGHLANDS AT 10Z AND ALSO
SOON TO ENTER THE WCENT MTNS NEAR KDUJ AND KFIG. THE FROZEN
PRECIP AT THE ONSET OF THIS UPCOMING WINTRY EVENT APPEARS TO BE
VERY MINOR AND ONLY A FEW HUNDREDTHS OF AN INCH AT MOST THROUGH
15Z. THE BIGGEST THREAT WILL BE A GLAZE OF ICE FROM FZRA AS THE
LIGHT RAIN OVERSPREADS THE AREA LATER THIS MORNING /AND EARLY THIS
AFTERNOON ACROSS THE NE/.
HIGH RES MODELS AND SFC OBS FAVOR THE PTYPE BEING LIGHT SLEET OR
FREEZING RAIN NEAR AND TO THE WEST OF RT 219...WHILE AREAS FURTHER
EAST SHOULD START OUT WITH SOME SHOWERS OF SLEET AND SNOW...BEFORE
THE TEMPS IN THE 900-800MB LAYER INCH UP ABOVE THE FREEZING MARK
THIS AFTERNOON. LATEST HRRR SUGGEST THAT THE STRONGEST NW-SE
ORIENTED BAROCLINIC ZONE AND GREATEST ISENT LIFT WILL OCCUR ACROSS
THE WEST-CENTRAL AND SCENT MTNS /BETWEEN I70/76 AND I-80 LATE THIS
MORNING AND THIS AFTERNOON.
INCREASING...NORTHERLY LLVL AGEOSTROPIC FLOW AND AN INITIAL 5-10F
T/TD SPREAD WILL CAUSE TEMPS IN MOST PLACES TO STRUGGLE TO CLIMB
ABOVE THE 32F MARK UNTIL LATE IN THE AFTERNOON. IF ANYTHING...FCST
MAX TEMPS TODAY COULD BE A FEW DEG F ON THE HIGH SIDE. THAT WILL
DEPEND STRONGLY ON HOW QUICK THE STEADIER LIGHT PRECIP
ARRIVES...AND IT/S PERSISTENCE DURING THE AFTERNOON HOURS. MAX
TEMPS ACROSS THE SCENT VALLEYS AND LOWER SUSQ VALLEY WILL BE IN
THE 35-40F RANGE.
NO CHANGES WERE MADE TO THE TIMING AND LOCATION OF THE CURRENT
WINTER WEATHER ADVISORIES ACROSS THE REGION.
BROKE OUT FOUR ZONES FOR THE WSW...WITH SOMERSET COUNTY SEEING THE
WINTRY PRECIP FIRST...THE 5 ADDITIONAL SOUTHWEST COUNTIES ACROSS
THE LAUREL HIGHLANDS SHORTLY AFTERWARD EARLY TODAY/.
THE CENTRAL MOUNTAIN AND LYCOMING VALLEY ARE THE THIRD
BREAKOUT...WHERE THE -FZRA WILL CHANGE OVER IN VALLEY LOCATIONS
BEFORE THE RIDGES EARLY THIS AFTERNOON.
ACROSS THE FAR NORTH...IT WILL BE MOST PROBLEMATIC TO MIX OUT THE
SHALLOW COLD AIR. GIVEN THE VERY COLD AIR IN THE TEENS ACROSS THAT
REGION EARLY TODAY /AND ANY SIGNIF INSOLATION BEING CUT-OFF BY THE
THICKENING CLOUDS THIS MORNING/ IT MAY NOT REACH FREEZING UNTIL
AFTER 00Z SAT.
WARMER AIR SHOULD WIN OUT IN THE EARLY AFTN IN THE SW/CENT MTNS
AND BY EVENING IN THE NRN TIER - WHERE IT COULD BE
HEAVIEST/THICKEST AS IT LINGERS THERE THE LONGEST TIME.
THE FAR SOUTHEAST CONTINUES TO REMAINS OUTSIDE OF THE ADVISORY
AREA...BUT COULD SEE SOME ICE PELLETS AT THE START...OR PERHAPS
VERY SPOTTY FREEZING RAIN UNTIL AROUND 14Z. AT THIS TIME...THE
CHANCES OF FZRA ARE STILL TOO LOW TO EXPAND THE ADVISORY THERE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SATURDAY/...
WAA AHEAD OF APPROACHING SFC LOW SHOULD PUSH TEMPS ABV FREEZING
EVERYWHERE LATER TONIGHT INTO SAT AS HEAVIEST RAIN OVERSPREADS
THE REGION W/PASSAGE OF LL JET AND PLUME OF ANOMALOUS PWATS. HAVE
INCREASED POPS UPWARDS BASED ON LATEST ENSEMBLE DATA...WHICH
SUPPORTS STORM TOTAL RAIN AMTS BY SAT NIGHT CLOSE TO 1 INCH OVER
THE NORTHERN AND EASTERN HALF OF CENTRAL PA. SLIGHTLY LESS ACROSS
THE LOWER CENTRAL PORTIONS OF THE STATE. THE LATEST GEFS AND
ENSEMBLE EC RUNS SHOW AN INCREASE IN PRECIPITATION AS THE LOW
MOVES OFF SHORE.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
BUILDING MODEL CONSENSUS FOR A DRY SUNDAY. RIDGING AT SFC AND
ALOFT IS BUILDING IN BEHIND THE SHORTWAVE. THE 12Z ECENS AND GEFS
REMAIN IN AGREEMENT IN KEEPING COASTAL DEVELOPMENT OFFSHORE EARLY
NEXT WEEK. HOWEVER...THE MODELS DIVERGE BY TUESDAY AND AS NORTHERN
STREAM SHORTWAVE DIVES SE INTO THE REGION...THE EC RETROGRADES THE
LOW OFF THE COAST AND ITS RESULTANT MOISTURE AND THE SHORTWAVE
DEEPENS AND MOVES NORTHEASTWARD. THIS WOULD BRING ANOTHER
SIGNIFICANT RAIN TO THE EASTERN HALF OF PA. THE GFS IS MUCH MORE
MILDER...WITH MAINLY ZONAL FLOW WITH A SHALLOW SHORTWAVE AND ONLY
A SLIGHT CHANCE OF RAIN/SNOW SHOWERS TUESDAY. DUE TO THIS
DICHOTOMY HAVE ONLY LEFT SLIGHT TO CHANCE POPS IN...WITH HIGHER
CHANCE IN THE EAST DUE TO THE HIGHER PROBABILITIES. CHANCE
RELATIVELY HIGH CONFIDENCE IN DRY WEATHER BY WED...WHEN BOTH ECENS
AND GEFS SHOW A LARGE SFC HIGH BUILDING IN FROM THE GRT LKS. NO
COLD WX IN SIGHT. TEMPS SLIGHTLY ABV NORMAL THE FIRST HALF OF NEXT
WEEK MAY BECOME SIGNIFICANTLY ABV NORMAL BY LATE NEXT WEEK...AS
ALL MED RANGE GUIDANCE SHOWING BROAD ZONAL FLOW ACROSS THE CONUS.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
IN ADVANCE OF A MID/UPPER TROUGH AND SFC LOW EJECTING EWD FROM
THE SOUTH-CENTRAL PLAINS...MOISTURE OVERRUNNING RETREATING SFC
HIGH AND ASSOCD WEDGE OF SHALLOW COLD AIR NEAR THE GROUND OVER
INTERIOR PA WILL LEAD TO POCKETS OF MIXED WINTRY PCPN EARLY TODAY
ACROSS THE AIRSPACE. REGIONAL RADAR TRENDS SHOW EXPANDING AREA OF
RETURNS MOVG ENEWD FROM NRN WV INTO SWRN PA. CIGS ARE LOWERING ON
SCHEDULE...GRADUALLY DROPPING TO MVFR AND IFR BY TONIGHT. BLYR
TEMPS SHOULD SLOWLY WARM TO CHANGE ANY LINGERING -FZRA TO A COLD
MODERATE RAIN BY LATE TONIGHT...WHICH WILL CONTINUE THROUGH THE
DAY ON SATURDAY. TEMPS MAY BE COLD ENOUGH TO SUPPORT A TRANSITION
BACK TO SNOW ON THE NW SIDE OF LOW TRACKING FROM WV THROUGH THE
DELMARVA LATE SAT INTO SAT NGT.
OUTLOOK...
SAT...MVFR/IFR IN RAIN. SNOW POSSIBLE N/W AND GUSTY NNW WINDS SAT
NGT.
SUN...PCPN ENDING EAST EARLY...BECOMING VFR.
MON...MAINLY VFR.
TUE...VFR/MVFR WITH CHC OF RAIN/SNOW.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 5 PM EST THIS AFTERNOON FOR
PAZ004>006-010>012-037-041-042.
WINTER WEATHER ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
PAZ017>019-027-028-045-046-049-050.
WINTER WEATHER ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
PAZ024>026-033>035.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...FITZGERALD/CERU
AVIATION...STEINBUGL
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
536 AM EST FRI DEC 5 2014
.SYNOPSIS...
MILD AND MOIST AIR RIDING NORTHEAST AND OVER A SHALLOW COLD
AIRMASS STUCK IN PLACE ACROSS PENNSYLVANIA WILL BRING PERIODS OF
LIGHT FREEZING RAIN AND SLEET TODAY...ESPECIALLY DURING THE
AFTERNOON HOURS. MUCH OF THE PRECIPITATION LATE TODAY WILL CHANGE
TO PLAIN RAIN...HOWEVER POCKETS OF FREEZING RAIN ARE STILL LIKELY
INTO EARLY TONIGHT ACROSS THE RIDGES OF CENTRAL PENNSYLVANIA.
A SECOND SURGE OF PRECIPITATION IN THE FORM OF PLAIN RAIN WILL
IMPACT THE REGION ON SATURDAY...FOLLOWED BY DRY WEATHER FOR
SUNDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE MAINLY CLEAR SKIES EARLIER DURING THE OVERNIGHT LED TO AREAS
OF STRONG RADIATIONAL COOLING. 10Z TEMPS RANGE FROM NEAR 20F
ACROSS OUR FAR NE ZONES...TO THE MID AND UPPER 20S THROUGHOUT MUCH
OF THE CENTRAL VALLEYS AND MIDDLE SUSQUEHANNA VALLEY. TEMPS WERE
HOVERING AROUND 30-32F ACROSS THE SW NEAR KJST AND KAOO.
SKIES HAVE BECOME OVERCAST ACROSS MUCH OF THE REGION THIS MORNING
IN THE FORM OF A MULTI-LAYERED CLOUD DECK. AN ARC OF SHOWERY LIGHT
PRECIP WAS HEADING ACROSS THE LAUREL HIGHLANDS AT 10Z AND ALSO
SOON TO ENTER THE WCENT MTNS NEAR KDUJ AND KFIG. THE FROZEN
PRECIP AT THE ONSET OF THIS UPCOMING WINTRY EVENT APPEARS TO BE
VERY MINOR AND ONLY A FEW HUNDREDTHS OF AN INCH AT MOST THROUGH
15Z. THE BIGGEST THREAT WILL BE A GLAZE OF ICE FROM FZRA AS THE
LIGHT RAIN OVERSPREADS THE AREA LATER THIS MORNING /AND EARLY THIS
AFTERNOON ACROSS THE NE/.
HIGH RES MODELS AND SFC OBS FAVOR THE PTYPE BEING LIGHT SLEET OR
FREEZING RAIN NEAR AND TO THE WEST OF RT 219...WHILE AREAS FURTHER
EAST SHOULD START OUT WITH SOME SHOWERS OF SLEET AND SNOW...BEFORE
THE TEMPS IN THE 900-800MB LAYER INCH UP ABOVE THE FREEZING MARK
THIS AFTERNOON. LATEST HRRR SUGGEST THAT THE STRONGEST NW-SE
ORIENTED BAROCLINIC ZONE AND GREATEST ISENT LIFT WILL OCCUR ACROSS
THE WEST-CENTRAL AND SCENT MTNS /BETWEEN I70/76 AND I-80 LATE THIS
MORNING AND THIS AFTERNOON.
INCREASING...NORTHERLY LLVL AGEOSTROPIC FLOW AND AN INITIAL 5-10F
T/TD SPREAD WILL CAUSE TEMPS IN MOST PLACES TO STRUGGLE TO CLIMB
ABOVE THE 32F MARK UNTIL LATE IN THE AFTERNOON. IF ANYTHING...FCST
MAX TEMPS TODAY COULD BE A FEW DEG F ON THE HIGH SIDE. THAT WILL
DEPEND STRONGLY ON HOW QUICK THE STEADIER LIGHT PRECIP
ARRIVES...AND IT/S PERSISTENCE DURING THE AFTERNOON HOURS. MAX
TEMPS ACROSS THE SCENT VALLEYS AND LOWER SUSQ VALLEY WILL BE IN
THE 35-40F RANGE.
NO CHANGES WERE MADE TO THE TIMING AND LOCATION OF THE CURRENT
WINTER WEATHER ADVISORIES ACROSS THE REGION.
BROKE OUT FOUR ZONES FOR THE WSW...WITH SOMERSET COUNTY SEEING THE
WINTRY PRECIP FIRST...THE 5 ADDITIONAL SOUTHWEST COUNTIES ACROSS
THE LAUREL HIGHLANDS SHORTLY AFTERWARD EARLY TODAY/.
THE CENTRAL MOUNTAIN AND LYCOMING VALLEY ARE THE THIRD
BREAKOUT...WHERE THE -FZRA WILL CHANGE OVER IN VALLEY LOCATIONS
BEFORE THE RIDGES EARLY THIS AFTERNOON.
ACROSS THE FAR NORTH...IT WILL BE MOST PROBLEMATIC TO MIX OUT THE
SHALLOW COLD AIR. GIVEN THE VERY COLD AIR IN THE TEENS ACROSS THAT
REGION EARLY TODAY /AND ANY SIGNIF INSOLATION BEING CUT-OFF BY THE
THICKENING CLOUDS THIS MORNING/ IT MAY NOT REACH FREEZING UNTIL
AFTER 00Z SAT.
WARMER AIR SHOULD WIN OUT IN THE EARLY AFTN IN THE SW/CENT MTNS
AND BY EVENING IN THE NRN TIER - WHERE IT COULD BE
HEAVIEST/THICKEST AS IT LINGERS THERE THE LONGEST TIME.
THE FAR SOUTHEAST CONTINUES TO REMAINS OUTSIDE OF THE ADVISORY
AREA...BUT COULD SEE SOME ICE PELLETS AT THE START...OR PERHAPS
VERY SPOTTY FREEZING RAIN UNTIL AROUND 14Z. AT THIS TIME...THE
CHANCES OF FZRA ARE STILL TOO LOW TO EXPAND THE ADVISORY THERE. &&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SATURDAY/...
WAA AHEAD OF APPROACHING SFC LOW SHOULD PUSH TEMPS ABV FREEZING
EVERYWHERE LATER TONIGHT INTO SAT AS HEAVIEST RAIN OVERSPREADS
THE REGION W/PASSAGE OF LL JET AND PLUME OF ANOMALOUS PWATS. HAVE
INCREASED POPS UPWARDS BASED ON LATEST ENSEMBLE DATA...WHICH
SUPPORTS STORM TOTAL RAIN AMTS BY SAT NIGHT CLOSE TO 1 INCH OVER
THE NORTHERN AND EASTERN HALF OF CENTRAL PA. SLIGHTLY LESS ACROSS
THE LOWER CENTRAL PORTIONS OF THE STATE. THE LATEST GEFS AND
ENSEMBLE EC RUNS SHOW AN INCREASE IN PRECIPITATION AS THE LOW
MOVES OFF SHORE.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
BUILDING MODEL CONSENSUS FOR A DRY SUNDAY. RIDGING AT SFC AND
ALOFT IS BUILDING IN BEHIND THE SHORTWAVE. THE 12Z ECENS AND GEFS
REMAIN IN AGREEMENT IN KEEPING COASTAL DEVELOPMENT OFFSHORE EARLY
NEXT WEEK. HOWEVER...THE MODELS DIVERGE BY TUESDAY AND AS NORTHERN
STREAM SHORTWAVE DIVES SE INTO THE REGION...THE EC RETROGRADES THE
LOW OFF THE COAST AND ITS RESULTANT MOISTURE AND THE SHORTWAVE
DEEPENS AND MOVES NORTHEASTWARD. THIS WOULD BRING ANOTHER
SIGNIFICANT RAIN TO THE EASTERN HALF OF PA. THE GFS IS MUCH MORE
MILDER...WITH MAINLY ZONAL FLOW WITH A SHALLOW SHORTWAVE AND ONLY
A SLIGHT CHANCE OF RAIN/SNOW SHOWERS TUESDAY. DUE TO THIS
DICHOTOMY HAVE ONLY LEFT SLIGHT TO CHANCE POPS IN...WITH HIGHER
CHANCE IN THE EAST DUE TO THE HIGHER PROBABILITIES. CHANCE
RELATIVELY HIGH CONFIDENCE IN DRY WEATHER BY WED...WHEN BOTH ECENS
AND GEFS SHOW A LARGE SFC HIGH BUILDING IN FROM THE GRT LKS. NO
COLD WX IN SIGHT. TEMPS SLIGHTLY ABV NORMAL THE FIRST HALF OF NEXT
WEEK MAY BECOME SIGNIFICANTLY ABV NORMAL BY LATE NEXT WEEK...AS
ALL MED RANGE GUIDANCE SHOWING BROAD ZONAL FLOW ACROSS THE CONUS.
&&
.AVIATION /10Z FRIDAY THROUGH TUESDAY/...
IN ADVANCE OF A MID/UPPER TROUGH AND SFC LOW EJECTING EWD FROM
THE SOUTH-CENTRAL PLAINS...MOISTURE OVERRUNNING RETREATING SFC
HIGH AND ASSOCD WEDGE OF SHALLOW COLD AIR NEAR THE GROUND OVER
INTERIOR PA WILL LEAD TO POCKETS OF MIXED WINTRY PCPN EARLY TODAY
ACROSS THE AIRSPACE. REGIONAL RADAR TRENDS SHOW EXPANDING AREA OF
RETURNS MOVG EWD OVER ERN OH INTO SWRN PA. LOOK FOR LOWERING CIGS
FROM SW TO NE EVENTUALLY DROPPING TO MVFR AND IFR BY TONIGHT. BLYR
TEMPS SHOULD SLOWLY WARM TO CHANGE ANY LINGERING FREEZING PCPN TO
TO A COLD RAIN BY TONIGHT...WHICH WILL CONTINUE THROUGH SATURDAY.
TEMPS MAY BE COLD ENOUGH TO SUPPORT TRANSITION BACK TO SNOW ON THE
NW SIDE OF LOW TRACKING FROM WV THROUGH THE DELMARVA LATE SAT INTO
SAT NGT.
OUTLOOK...
SAT...MVFR/IFR IN RAIN. SNOW POSSIBLE N/W AND GUSTY NNW WINDS SAT
NGT.
SUN...PCPN ENDING EAST EARLY...BECOMING VFR.
MON...MAINLY VFR.
TUE...VFR/MVFR WITH CHC OF RAIN/SNOW.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 9 AM THIS MORNING TO 5 PM EST
THIS AFTERNOON FOR PAZ004>006-010>012-037-041-042.
WINTER WEATHER ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
PAZ017>019-027-028-045-046-049-050.
WINTER WEATHER ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
PAZ024>026-033>035.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...FITZGERALD/CERU
AVIATION...STEINBUGL
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
1005 PM CST SAT DEC 6 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 301 PM CST SAT DEC 6 2014
COMPLEX FORECAST OVER THE NEXT DAY AS AN UPPER WAVE MOVES ACROSS THE
AREA...ACCOMPANIED BY A LOW PRESSURE MOVING ACROSS THE CANADIAN
BORDER DRAGGING A COLD FRONT THROUGH THE REGION. AS OF THIS
AFTERNOON...LOW STRATUS HAS ERODED AND PUSHED OFF TO THE SOUTH OF
THE CWA. HOWEVER AS LOW LEVEL WINDS TURN MORE SOUTHEASTERLY AND
SOUTHERLY AHEAD OF THE APPROACHING FRONT...EXPECT THIS STRATUS TO
BEGIN STREAMING BACK INTO THE REGION. THE RAP SEEMS TO HAVE THE BEST
HANDLE ON THIS...AND THINK THIS LOW STRATUS SHOULD APPROACH SIOUX
CITY AROUND MIDNIGHT...PUSHING NORTH INTO THE EARLY MORNING
HOURS...LIKELY MAKING IT EVERYWHERE ALONG AND EAST OF THE JAMES
RIVER.
NEXT QUESTION IS FOG POTENTIAL. ONE THING GOING AGAINST WIDESPREAD
DENSE FOG IS THE STRONG SOUTHERLY BREEZE...WHICH WILL LIKELY BE
AVERAGING 15 TO 25 MPH...GUSTING 25 TO 35 MPH. PROBABLY EVEN A BIT
HIGHER ALONG THE BUFFALO RIDGE. HOWEVER MOISTURE IS SHALLOW AND NEAR
THE GROUND...SO STRATUS COULD COME IN LOW ENOUGH TO RESULT IN DENSE
FOG EVEN GIVEN THE WIND...WHICH THE RAP SUGGESTS. GIVEN THE
UNCERTAINTY WILL JUST INCLUDE PATCHY FOG IN THE GRIDS FOR NOW...AND
THE EVENING AND OVERNIGHT SHIFT WILL HAVE TO MONITOR TRENDS AND
ADJUST AS NEEDED.
THE NEXT QUESTION IS PRECIPITATION POTENTIAL. TWO ASPECTS TO
THIS...DRIZZLE WITH THE LOW LEVEL MOISTURE...AND RAIN WITH THE UPPER
LEVEL FEATURE AND FRONTOGENESIS. WITH REGARDS TO THE DRIZZLE
POTENTIAL...MOISTURE IS ORIGINALLY PRETTY SHALLOW WHICH WOULD SEEM
TO MAKE DRIZZLE UNLIKELY. BY LATER TONIGHT INTO TOMORROW MORNING
MOISTURE DEPTH BEGINS TO INCREASE...AS DOES LIFT IN THE MOISTURE
LAYER. THIS WOULD SEEM TO SUGGEST AN INCREASE IN THE DRIZZLE
POTENTIAL BY MID MORNING EAST OF THE JAMES RIVER. THE PASSAGE OF THE
FRONT WILL EVENTUALLY END THAT THREAT FROM WEST TO EAST THROUGH THE
AFTERNOON. THE UPPER LEVEL WAVE AND MID LEVEL FRONTOGENESIS WILL TRY
TO PRODUCE SOME LIGHT PRECIPITATION AS WELL FROM EARLY SUNDAY INTO
THE AFTERNOON. QUITE A BIT OF MID LEVEL DRY AIR FOR THIS
PRECIPITATION TO OVERCOME THOUGH...AND MOST MODELS ARE TRENDING
DRIER. SO DID CUT BACK QPF...WITH BEST CHANCE OF MEASURABLE
PRECIPITATION ALONG AND EAST OF INTERSTATE 29...WITH CHANCES
INCREASING AS YOU GO EAST.
LAST QUESTION IS PRECIPITATION TYPE. WITH QUITE A STRONG WARM NOSE
ALOFT...THINK ANYTHING WILL EITHER BE LIGHT RAIN OR FREEZING RAIN.
COULD SEE A BIT OF SLEET MIXED IN...BUT NOT EXPECTING IT TO BE A
PREDOMINANT TYPE. THUS PTYPE WILL PROBABLY COME DOWN TO SURFACE
TEMPERATURES. USED A BLEND OF RAW GUIDANCE...WEIGHTED TOWARDS THE
GEM...ECMWF AND WRF ARW FOR HOURLY TEMPERATURES TONIGHT INTO
TOMORROW. THIS WARMS SIOUX CITY ABOVE FREEZING BY 14Z...SIOUX FALLS
BY 16Z AND THE REMAINDER OF THE CWA BY 18Z. THUS I DO THINK A PERIOD
OF FREEZING DRIZZLE OR LIGHT FREEZING RAIN IS POSSIBLE. ALTHOUGH BY
THE TIME THE DRIZZLE INCREASES...WE COULD VERY WELL BE ABOVE
FREEZING...LIMITING THE FREEZING POTENTIAL. THE BEST CHANCE OF A
LIGHT COATING OF ICE SEEMS TO BE EAST OF INTERSTATE 29 WHERE COLD
AIR HOLDS ON A BIT LONGER. GIVEN THE UNCERTAINTY WILL HOLD OFF ON
ANY ADVISORY. BUT THOSE WITH MORNING TRAVEL PLANS SHOULD KEEP ALERT
OF THE FORECAST...AS EVEN JUST A LIGHT COATING OF ICE CAN CAUSE
IMPACTS. EVENING AND OVERNIGHT SHIFT WILL HAVE TO MONITOR
TRENDS...AND ISSUE ANY ADVISORY IF CONFIDENCE IN MORE WIDESPREAD
FREEZING DRIZZLE OR LIGHT FREEZING RAIN INCREASES.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 301 PM CST SAT DEC 6 2014
THE MAIN FOCUS IN THE MEDIUM AND EXTENDED FOCUSES ON TEMPERATURES.
WHILE MAJORITY OF PRECIPITATION WILL TAKE PLACE DURING THE DAY ON
SUNDAY...WILL HAVE TO WATCH FOR LOW STRATUS ROTATING BACK INTO THE
AREA BEHIND DEPARTING UPPER TROUGH SUNDAY NIGHT. SOUNDINGS SUGGEST
A VERY LIGHT PRECIPITATION POTENTIAL...IN THE FORM OF
FLURRIES/SPRINKLES/DRIZZLE.
COLDER AIR WILL NOT QUITE MAKE IT SOUTHWARD ON MONDAY...BUT THE
WESTERLY WIND AND LINGERING WARM AIR ALOFT WILL STILL ALLOW FOR
ABOVE NORMAL TEMPERATURES. A MORE DIRECT COOLDOWN WILL ARRIVE ON
TUESDAY AS SURFACE HIGH PRESSURE MOVES OVERHEAD. THE MISSOURI RIVER
VALLEY MAY STILL REACH THE MID 30S...BUT AREAS FURTHER NORTHEAST
COULD STRUGGLE TO CLIMB ABOVE FREEZING.
LOW LVL WARM ADVECTION BEGINS LATE TUESDAY AS MID-LVL HEIGHTS RISE
OVER THE CENTRAL CONUS. GFS/ECMWF CONSISTENT NOW IN BRINGING A
WEAK SHORTWAVE THROUGH THE AREA TUESDAY NIGHT AND WEDNESDAY...BUT
LITTLE IMPACT IS ANTICIPATED OTHER THAN CLOUD COVER.
THEN BEGINS A STRETCH OF ABOVE NORMAL TEMPERATURES...SOME THAT COULD
RIVAL SOME OF OUR WARMER TEMPERATURES RECORDED IN DECEMBER.
MODELS STILL DIFFERING TO SOME DEGREE ON MOISTURE RETURN AND
IMPACT ON STRATUS ACROSS THE REGION. ALOFT...TEMPERATURES ARE
SURELY IMPRESSIVE WITH 925MB TEMPERATURES BY SATURDAY APPROACHING
+10C...AND 850MB TEMPERATURES AROUND +15C...SOME OF THE WARMEST
READINGS RECORDED VIA SOUNDINGS IN DECEMBER AT ABERDEEN. MODEL
PREFERENCE CONTINUES TO FALL WITH THE ECMWF...WHICH DOES SHOW
STRATUS ADVECTING INTO THE AREA BY THURSDAY...BUT IS NOT NEARLY AS
AGGRESSIVE AS THE TYPICALLY OVERSATURATED GFS AND SUGGESTED A
SLIGHTLY MORE VEERED LOW LVL FLOW. THAT SAID...FOR TEMPERATURES
WED- SAT UTILIZED A BLEND OF WPC AND ECMWF...WHICH FALL ON THE
WARMEST SIDE OF GUIDANCE AND STILL MAY NOT BE WARM ENOUGH FOR
SATURDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1005 PM CST SAT DEC 6 2014
COMPLEX FORECAST OVER THE NEXT 12-24 HOURS. AS THE SOUTHERLY LOW
LEVEL JET INCREASES TONIGHT...EXPECT STRATUS AND/OR FOG TO MOVE BACK
INTO THE AREA FROM THE CENTRAL PLAINS. CEILINGS TO OUR SOUTH
CURRENTLY IFR...BUT ANTICIPATE THIS WILL LOWER AS IT STREAMS NORTH
BENEATH LOW LEVEL INVERSION...AND THUS WILL HAVE LIFR CEILINGS
DOMINANT FOR LATE TONIGHT THROUGH MID-LATE MORNING SUNDAY. STOUT
SOUTHERLY FLOW SHOULD HELP KEEP VISIBILITY FROM DROPPING TOO LOW...
HOWEVER IFR VISIBILITY POSSIBLE EAST OF THE JAMES RIVER VALLEY.
OTHER CONCERN IS DRIZZLE OR FREEZING DRIZZLE. THIS IS CERTAINLY A
POSSIBILITY WITH THE STRATUS...ESPECIALLY WITH WEAK LIFT FROM WARM
ADVECTION ABOVE THE STRATUS LAYER. HAVE INTRODUCED 2-3 HOUR WINDOW
OF POSSIBLE FREEZING PRECIPITATION FOR KFSD/KSUX WHERE STRATUS LAYER
MOISTURE SHOULD BE DEEPER. ANY ICING EXPECTED TO BE LIGHT...BUT WITH
POTENTIAL FOR ADVERSE EFFECTS ON AVIATION FROM ANY ICING...FELT IT
BEST TO INCLUDE MENTION FOR MOST PROBABLY TIME PERIOD.
VISIBILITY EXPECTED TO IMPROVE AT TAF SITES THROUGH THE AFTERNOON...
WITH LOW CEILINGS MOVING OUT TOWARD EVENING AS WINDS SHIFT TO THE
SOUTHWEST-WEST.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
SHORT TERM...CHENARD
LONG TERM...DUX
AVIATION...JH
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
552 PM CST SAT DEC 6 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 301 PM CST SAT DEC 6 2014
COMPLEX FORECAST OVER THE NEXT DAY AS AN UPPER WAVE MOVES ACROSS THE
AREA...ACCOMPANIED BY A LOW PRESSURE MOVING ACROSS THE CANADIAN
BORDER DRAGGING A COLD FRONT THROUGH THE REGION. AS OF THIS
AFTERNOON...LOW STRATUS HAS ERODED AND PUSHED OFF TO THE SOUTH OF
THE CWA. HOWEVER AS LOW LEVEL WINDS TURN MORE SOUTHEASTERLY AND
SOUTHERLY AHEAD OF THE APPROACHING FRONT...EXPECT THIS STRATUS TO
BEGIN STREAMING BACK INTO THE REGION. THE RAP SEEMS TO HAVE THE BEST
HANDLE ON THIS...AND THINK THIS LOW STRATUS SHOULD APPROACH SIOUX
CITY AROUND MIDNIGHT...PUSHING NORTH INTO THE EARLY MORNING
HOURS...LIKELY MAKING IT EVERYWHERE ALONG AND EAST OF THE JAMES
RIVER.
NEXT QUESTION IS FOG POTENTIAL. ONE THING GOING AGAINST WIDESPREAD
DENSE FOG IS THE STRONG SOUTHERLY BREEZE...WHICH WILL LIKELY BE
AVERAGING 15 TO 25 MPH...GUSTING 25 TO 35 MPH. PROBABLY EVEN A BIT
HIGHER ALONG THE BUFFALO RIDGE. HOWEVER MOISTURE IS SHALLOW AND NEAR
THE GROUND...SO STRATUS COULD COME IN LOW ENOUGH TO RESULT IN DENSE
FOG EVEN GIVEN THE WIND...WHICH THE RAP SUGGESTS. GIVEN THE
UNCERTAINTY WILL JUST INCLUDE PATCHY FOG IN THE GRIDS FOR NOW...AND
THE EVENING AND OVERNIGHT SHIFT WILL HAVE TO MONITOR TRENDS AND
ADJUST AS NEEDED.
THE NEXT QUESTION IS PRECIPITATION POTENTIAL. TWO ASPECTS TO
THIS...DRIZZLE WITH THE LOW LEVEL MOISTURE...AND RAIN WITH THE UPPER
LEVEL FEATURE AND FRONTOGENESIS. WITH REGARDS TO THE DRIZZLE
POTENTIAL...MOISTURE IS ORIGINALLY PRETTY SHALLOW WHICH WOULD SEEM
TO MAKE DRIZZLE UNLIKELY. BY LATER TONIGHT INTO TOMORROW MORNING
MOISTURE DEPTH BEGINS TO INCREASE...AS DOES LIFT IN THE MOISTURE
LAYER. THIS WOULD SEEM TO SUGGEST AN INCREASE IN THE DRIZZLE
POTENTIAL BY MID MORNING EAST OF THE JAMES RIVER. THE PASSAGE OF THE
FRONT WILL EVENTUALLY END THAT THREAT FROM WEST TO EAST THROUGH THE
AFTERNOON. THE UPPER LEVEL WAVE AND MID LEVEL FRONTOGENESIS WILL TRY
TO PRODUCE SOME LIGHT PRECIPITATION AS WELL FROM EARLY SUNDAY INTO
THE AFTERNOON. QUITE A BIT OF MID LEVEL DRY AIR FOR THIS
PRECIPITATION TO OVERCOME THOUGH...AND MOST MODELS ARE TRENDING
DRIER. SO DID CUT BACK QPF...WITH BEST CHANCE OF MEASURABLE
PRECIPITATION ALONG AND EAST OF INTERSTATE 29...WITH CHANCES
INCREASING AS YOU GO EAST.
LAST QUESTION IS PRECIPITATION TYPE. WITH QUITE A STRONG WARM NOSE
ALOFT...THINK ANYTHING WILL EITHER BE LIGHT RAIN OR FREEZING RAIN.
COULD SEE A BIT OF SLEET MIXED IN...BUT NOT EXPECTING IT TO BE A
PREDOMINANT TYPE. THUS PTYPE WILL PROBABLY COME DOWN TO SURFACE
TEMPERATURES. USED A BLEND OF RAW GUIDANCE...WEIGHTED TOWARDS THE
GEM...ECMWF AND WRF ARW FOR HOURLY TEMPERATURES TONIGHT INTO
TOMORROW. THIS WARMS SIOUX CITY ABOVE FREEZING BY 14Z...SIOUX FALLS
BY 16Z AND THE REMAINDER OF THE CWA BY 18Z. THUS I DO THINK A PERIOD
OF FREEZING DRIZZLE OR LIGHT FREEZING RAIN IS POSSIBLE. ALTHOUGH BY
THE TIME THE DRIZZLE INCREASES...WE COULD VERY WELL BE ABOVE
FREEZING...LIMITING THE FREEZING POTENTIAL. THE BEST CHANCE OF A
LIGHT COATING OF ICE SEEMS TO BE EAST OF INTERSTATE 29 WHERE COLD
AIR HOLDS ON A BIT LONGER. GIVEN THE UNCERTAINTY WILL HOLD OFF ON
ANY ADVISORY. BUT THOSE WITH MORNING TRAVEL PLANS SHOULD KEEP ALERT
OF THE FORECAST...AS EVEN JUST A LIGHT COATING OF ICE CAN CAUSE
IMPACTS. EVENING AND OVERNIGHT SHIFT WILL HAVE TO MONITOR
TRENDS...AND ISSUE ANY ADVISORY IF CONFIDENCE IN MORE WIDESPREAD
FREEZING DRIZZLE OR LIGHT FREEZING RAIN INCREASES.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 301 PM CST SAT DEC 6 2014
THE MAIN FOCUS IN THE MEDIUM AND EXTENDED FOCUSES ON TEMPERATURES.
WHILE MAJORITY OF PRECIPITATION WILL TAKE PLACE DURING THE DAY ON
SUNDAY...WILL HAVE TO WATCH FOR LOW STRATUS ROTATING BACK INTO THE
AREA BEHIND DEPARTING UPPER TROUGH SUNDAY NIGHT. SOUNDINGS SUGGEST
A VERY LIGHT PRECIPITATION POTENTIAL...IN THE FORM OF
FLURRIES/SPRINKLES/DRIZZLE.
COLDER AIR WILL NOT QUITE MAKE IT SOUTHWARD ON MONDAY...BUT THE
WESTERLY WIND AND LINGERING WARM AIR ALOFT WILL STILL ALLOW FOR
ABOVE NORMAL TEMPERATURES. A MORE DIRECT COOLDOWN WILL ARRIVE ON
TUESDAY AS SURFACE HIGH PRESSURE MOVES OVERHEAD. THE MISSOURI RIVER
VALLEY MAY STILL REACH THE MID 30S...BUT AREAS FURTHER NORTHEAST
COULD STRUGGLE TO CLIMB ABOVE FREEZING.
LOW LVL WARM ADVECTION BEGINS LATE TUESDAY AS MID-LVL HEIGHTS RISE
OVER THE CENTRAL CONUS. GFS/ECMWF CONSISTENT NOW IN BRINGING A
WEAK SHORTWAVE THROUGH THE AREA TUESDAY NIGHT AND WEDNESDAY...BUT
LITTLE IMPACT IS ANTICIPATED OTHER THAN CLOUD COVER.
THEN BEGINS A STRETCH OF ABOVE NORMAL TEMPERATURES...SOME THAT COULD
RIVAL SOME OF OUR WARMER TEMPERATURES RECORDED IN DECEMBER.
MODELS STILL DIFFERING TO SOME DEGREE ON MOISTURE RETURN AND
IMPACT ON STRATUS ACROSS THE REGION. ALOFT...TEMPERATURES ARE
SURELY IMPRESSIVE WITH 925MB TEMPERATURES BY SATURDAY APPROACHING
+10C...AND 850MB TEMPERATURES AROUND +15C...SOME OF THE WARMEST
READINGS RECORDED VIA SOUNDINGS IN DECEMBER AT ABERDEEN. MODEL
PREFERENCE CONTINUES TO FALL WITH THE ECMWF...WHICH DOES SHOW
STRATUS ADVECTING INTO THE AREA BY THURSDAY...BUT IS NOT NEARLY AS
AGGRESSIVE AS THE TYPICALLY OVERSATURATED GFS AND SUGGESTED A
SLIGHTLY MORE VEERED LOW LVL FLOW. THAT SAID...FOR TEMPERATURES
WED- SAT UTILIZED A BLEND OF WPC AND ECMWF...WHICH FALL ON THE
WARMEST SIDE OF GUIDANCE AND STILL MAY NOT BE WARM ENOUGH FOR
SATURDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 552 PM CST SAT DEC 6 2014
COMPLEX FORECAST OVER THE NEXT 24 HOURS. AS THE SOUTHERLY LOW LEVEL
JET INCREASES TONIGHT...EXPECT STRATUS AND/OR FOG TO MOVE BACK INTO
THE AREA FROM THE CENTRAL PLAINS. CEILINGS TO OUR SOUTH CURRENTLY
IFR...BUT ANTICIPATE THIS WILL LOWER AS IT STREAMS NORTH BENEATH LOW
LEVEL INVERSION...AND THUS WILL HAVE LIFR CEILINGS DOMINANT FOR LATE
TONIGHT THROUGH MID-LATE MORNING SUNDAY. STOUT SOUTHERLY FLOW SHOULD
HELP KEEP VISIBILITY FROM DROPPING TOO LOW...HOWEVER IFR VISIBILITY
POSSIBLE EAST OF THE JAMES RIVER VALLEY.
OTHER CONCERN IS DRIZZLE OR FREEZING DRIZZLE. THIS IS CERTAINLY A
POSSIBILITY WITH THE STRATUS...ESPECIALLY WITH WEAK LIFT FROM WARM
ADVECTION ABOVE THE STRATUS LAYER. HAVE INTRODUCED 2-3 HOUR WINDOW
OF POSSIBLE FREEZING PRECIPITATION FOR KFSD/KSUX WHERE STRATUS LAYER
MOISTURE SHOULD BE DEEPER. ANY ICING EXPECTED TO BE LIGHT...BUT WITH
POTENTIAL FOR ADVERSE EFFECTS ON AVIATION FROM ANY ICING...FELT IT
BEST TO INCLUDE MENTION FOR MOST PROBABLY TIME PERIOD.
OVERALL CONDITIONS AT TAF SITES WILL IMPROVE DURING THE AFTERNOON.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
SHORT TERM...CHENARD
LONG TERM...DUX
AVIATION...CHENARD
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
213 PM MST FRI DEC 5 2014
.SHORT TERM...THIS EVENING THROUGH SATURDAY NIGHT
ISSUED AT 207 PM MST FRI DEC 5 2014
UPPER LEVEL ANALYSIS SHOWS A RIDGE OVER THE WESTERN
CONUS...WITH NORTHWEST FLOW OVER THE NORTHERN PLAINS. CANADIAN
SURFACE HIGH IS MOVING SOUTHWARD INTO MT/ND. SKIES ARE PARTLY
CLOUDY...WITH GENERALLY LIGHT WINDS AND TEMPS IN THE UPPER 30S AND
40S.
LIGHT WINDS WILL BECOME SOUTHEASTERLY TONIGHT AS THE SURFACE HIGH
CROSSES ND...BRINGING MOISTURE INTO THE AREA. SEVERAL MODELS ARE
STILL HINTING AT SOME FOG SETTING UP AROUND THE AREA. THE HRRR AND
RAP ARE SHOWING LOW CEILINGS ACROSS THE SD PLAINS DEVELOPING AFTER
MIDNIGHT...AND LATEST RUNS ALSO HAVE FOG WRAPPING AROUND THE
SOUTHERN HILLS INTO NORTHEAST WY. MEANWHILE THE NAM HAS THE BEST
CHANCES FOR FOG AROUND THE HILLS AND INTO NORTHEAST WY...NOT SO MUCH
ON THE SD PLAINS. THE NAM SEEMS TO BE OVERESTIMATING MOISTURE
LATELY...AND SINCE WINDS IN NORTHEAST WY LOOK A LITTLE STRONGER
OVERNIGHT...HAVE MORE UNCERTAINTY ABOUT FOG DEVELOPMENT THERE.
DECREASED AREAS OF FOG TO PATCHY ACROSS NORTHEAST WY...KEEPING AREAS
OF FOG JUST EAST OF THE HILLS. COULD ALSO BE SOME PATCHY FOG IN
SURROUNDING AREAS ACROSS THE SD PLAINS. AS THE SURFACE HIGH MOVES
SOUTHEAST OVERNIGHT...COLD AIR WILL ADVECT INTO THE EASTERN CWA.
LOWS WILL RANGE FROM THE TEENS ACROSS NORTH CENTRAL/NORTHWEST SD TO
THE UPPER 20S IN NORTHEAST WY.
SOUTHERLY WINDS WILL BECOME BREEZY BY LATE SATURDAY MORNING AS THE
PRESSURE GRADIENT TIGHTENS BETWEEN THE HIGH PRESSURE TO THE EAST AND
THE INCOMING LOW. EXPECT FOG TO DISSIPATE BY MID-MORNING. THERE IS
SOME UNCERTAINTY WITH TEMPS ON SATURDAY...AS MODELS HAVE A 10-DEGREE
SPREAD FOR HIGHS IN SOME PLACES. WITH SOUTHERLY BOUNDARY-LAYER WINDS
AND WARM AIR ADVECTION...KEPT TEMPS MILD...IN THE MID 30S NORTH AND
EAST TO THE UPPER 40S FARTHER WEST. LOWS SATURDAY NIGHT WILL BE IN
THE 20S TO LOWER 30S.
.LONG TERM...SUNDAY THROUGH FRIDAY
ISSUED AT 207 PM MST FRI DEC 5 2014
MODELS ARE IN GOOD AGREEMENT DURING THE EXTENDED
PERIOD...WITH RELATIVELY HIGH PREDICTABILITY THROUGH AT LEAST
WEDNESDAY. IN THE MEAN...THERE WILL BE A LONG-WAVE TROUGH OFF THE
WEST COAST WITH A LONG-WAVE RIDGE NEAR THE CNTRL CONUS.
ON SUNDAY A SHORT-WAVE TROUGH WILL MOVE ACROSS THE FAR NRN PLAINS
AND THROUGH THE L/W RIDGE...BRINGING A COLD FRONT AND NORTHWEST WIND
SHIFT ACROSS THE CWA. THIS WILL BRING SCT SHRASN TO THE BLKHLS. ON
MONDAY THROUGH WEDNESDAY THE RIDGE REBOUNDS...BUT WITH A WEAK SHORT-
WAVE TROUGH SLOWLY MOVING ACROSS THE NRN PLAINS. THIS IS NOT
EXPECTED TO BRING ANY PRECIP TO THE CWA GIVEN THE LIMITED FORCING
FOR ASCENT AND LACK OF LOW- TO MID-LEVEL MOISTURE.
ON THURSDAY AND FRIDAY...THE LONG-WAVE TROUGH MOVES INTO THE ERN
HALF OF THE CONUS WITH SOUTHWEST FLOW ALOFT DEVELOPING ACROSS THE
CWA IN RESPONSE TO A DEEP UPPER LOW COMING ONSHORE NEAR CA. THE GFS
SEEMS A BIT AGGRESSIVE WITH THIS LOW...SO HAVE KEPT THE FORECAST DRY
THROUGH FRIDAY. NEVERTHELESS...THERE ARE INDICATIONS THAT A BIG
STORM COULD BE LOOMING ON THE HORIZON FOR LATE NEXT WEEKEND.
&&
.AVIATION...FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING
ISSUED AT 207 PM MST FRI DEC 5 2014
VFR CONDITIONS EXPECTED THROUGH EARLY TONIGHT. IFR/LIFR
STRATUS/FOG MAY DEVELOP LATE TONIGHT OVER NORTHEAST WYOMING AND
WESTERN SOUTH DAKOTA.
&&
.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&
$$
SHORT TERM...POJORLIE
LONG TERM...BUNKERS
AVIATION...MCKEMY
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
309 PM CST FRI DEC 5 2014
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 304 PM CST FRI DEC 5 2014
ALTHOUGH VISIBILITY HAS IMPROVED...FOG CONTINUES TO RESIDE THROUGH
NORTHWEST IOWA THIS AFTERNOON...SO THE BIGGEST CHALLENGE TONIGHT
REMAINS HOW QUICKLY FOG ERODES AS DRIER AIR FILTERS IN BEHIND THE
SURFACE TROUGH PUSHING ACROSS THE REGION. WATCHING THE TRENDS
THROUGH THE AFTERNOON...VISIBILITIES HAVE QUICKLY IMPROVED AS THE
WINDS TRANSITIONED TO NORTHERLY BEHIND THE TROUGH AND THE DRIER AIR
DRAINED IN. USING THAT AND RAP 925 MB RH FIELDS WHICH HAVE ALSO
CORRELATED WELL WITH THE FOG...HAVE THE FOG LINGERING THROUGH
PORTIONS OF NORTHWEST IOWA THROUGH THE EVENING THEN SLOWLY ERODING
FROM THE NORTH AND WEST AS DRIER AIR TAKES OVER DURING THE NIGHT.
COLDER AIR WILL ALSO FILTER SOUTH OVERNIGHT...WITH LOWS BOTTOMING
OUT AROUND 10 THROUGH THE HIGHWAY 14 CORRIDOR TO THE UPPER TEENS
THROUGH THE MISSOURI RIVER VALLEY.
SURFACE HIGH PRESSURE SETTLES INTO THE REGION ON SATURDAY...SO
SHOULD SEE SOME SUN ALONG WITH RELATIVELY LIGHT WINDS DURING THE DAY
WITH A WEAK GRADIENT EXISTING ACROSS THE REGION. WITH THERMAL
PROFILES A LITTLE COOLER HIGHS WILL RANGE FROM THE LOWER 30S NORTH
TO UPPER 30S SOUTH.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 304 PM CST FRI DEC 5 2014
THE PRIMARY FORECAST CONCERNS IN THE MEDIUM AND SHORT RANGE CONTINUE
TO FOCUS ON LIGHT PRECIPITATION CHANCES SUNDAY AND WARMUP INTO
NEXT WEEK/WEEKEND.
SUNDAY...MODELS STILL ON TRACK BRINGING TWO PIECES OF SHORTWAVE
ENERGY INTO THE REGION LATE SATURDAY NIGHT AND INTO SUNDAY. THE
FIRST WAVE WILL LIFT NORTHWARD FROM THE SOUTHWESTERN US WITH THE
SECOND WAVE DIPPING SOUTHEAST FROM THE PACIFIC NORTHWEST.
AGAIN...MOISTURE REMAINS RATHER SHALLOW IN NATURE AS THESE WAVES
MOVE THROUGH BUT AM ANTICIPATING A NARROW CORRIDOR OF LIGHT FREEZING
RAIN/DRIZZLE DEVELOPING NEAR DAYBREAK ALONG AND WEST OF I-29. WHILE
THE ATMOSPHERIC PROFILE LACKS ICE CRYSTALS FOR MOST OF THE
EVENT...THERE COULD BE A BRIEF WINDOW OF SATURATION EARLY IN THE
AFTERNOON WHICH WOULD OWE TO SLEET INTRODUCTION ESPECIALLY IN THE NE
ZONES. THE PRECIPITATION SHOULD BE LIGHT ENOUGH TO AVOID ANY
MAJOR ICING CONCERNS...ESPECIALLY SINCE SFC TEMPERATURES WILL
CONTINUE TO RISE THROUGH THE MORNING AND SHOULD CLIMB ABOVE
FREEZING IN THE AFTERNOON.
NEXT WEEK...SLIGHT MODEL DIFFERENCES CONTINUE FOR MUCH OF NEXT WEEK
WITH BOTH MAJOR EXTENDED RANGE MODELS SHOWING INCREASED RIDGING
ACROSS THE CONUS INTO NEXT WEEKEND. TEMPERATURES WILL COOL SLIGHTLY
BEHIND SUNDAYS DEPARTING TROUGH...BUT STILL AVERAGE NEAR OR SLIGHTLY
ABOVE SEASONAL NORMALS. FAIRLY SUBSTANCIAL DIFFERENCES PERSIST IN
THE HANDLING OF SHORTWAVE ENERGY MOVING THROUGH THE PACIFIC
NORTHWEST ON MONDAY. ECMWF KEEPS THIS ENERGY WELL NORTH OF THE
CWA...MEANWHILE THE GFS PULLS THE WAVE THROUGH THE CENTRAL PLAINS.
THE END RESULTS COULD BE SUBSTANCIAL DIFFERENT FOR WEDNESDAY-
FRIDAY. SHOULD THE GFS SOLUTION VERIFY...THE RESULT WOULD BE
INCREASED CLOUD COVER...FOG...AND SLIGHTLY COOLER TEMPS IN THE
LOCAL AREA. ON THE FLIPSIDE...THE MORE AMPLIFIED ECMWF SOLN COULD
SUGGEST VERY WARM TEMPERATURES THURSDAY AND INTO THE WEEKEND. FOR
TODAY...PREFERENCES CONTINUE TO FALL TOWARDS THE ECMWF...BUT WILL
HEDGE A BIT TOWARDS THE OTHER CAMP OF SOLNS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1111 AM CST FRI DEC 5 2014
DENSE FOG EAST OF THE INTERSTATE 29 CORRIDOR WILL ONLY SLOWLY
ERODE THROUGH THE AFTERNOON AS A BOUNDARY WORKS THROUGH THE
REGION...PULLING DRIER AIR INTO THE AREA FROM WEST TO EAST. BY
TONIGHT MAINLY VFR CONDITIONS SHOULD DOMINATE...THROUGH CANNOT
RULE OUT PATCHY FOG REDEVELOPMENT OVERNIGHT AS WINDS LIGHTEN UP A
BIT.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
SHORT TERM...JM
LONG TERM...DUX
AVIATION...JM
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
339 PM CST FRI DEC 5 2014
.DISCUSSION...
FOR TODAY...THE ONLY SIGNIFICANT CHANGE TO THE FORECAST FROM THE
MORNING UPDATE WAS TO INCREASE POPS SLIGHTLY ALONG AND SOUTHEAST
OF THE FORECAST POSITION OF THE COLD FRONT ACROSS THE CWA THROUGH
TONIGHT. EARLY AFTERNOON RUNS OF THE HRRR CONSISTENTLY ADVERTISE A
SCATTERED LINE OF SHOWERS DEVELOPING ALONG THE LEADING EDGE OF THE
COLD FRONT AS IT MOVES ACROSS THE CWA. AT 20Z/2PM...THE SURFACE
OBSERVATIONS INDICATED THAT THE LEADING EDGE OF THE COLD FRONT WAS
LOCATED ALONG A LINE FROM ARDMORE TO BOWIE TO BRECKENRIDGE. EARLY
AFTERNOON VISIBLE SATELLITE IMAGERY SHOWED A THIN LINE OF CUMULUS
ORGANIZING ALONG THE FRONT...SUPPORTING THE HRRR FORECAST FOR
STRONGER LIFT AND BETTER RAIN SHOWER CHANCES IN THE IMMEDIATE
VICINITY OF THE FRONT.
DESPITE THE INCREASE IN RAIN CHANCES IN THE SHORT TERM
FORECAST...CONTINUE TO THINK CHANCES OF LIGHTNING ARE LOW. 19Z
AIRCRAFT SOUNDINGS FROM KDFW AND KDAL AIRPORTS CONTINUE TO SHOW
MID-LEVEL LAPSE RATES THAT ARE TOO STABLE TO SUPPORT FREE
CONVECTION. LAPSE RATES HAVE INCREASED A BIT FROM 12Z...LIKELY DUE
FROM DYNAMIC LIFT ASSOCIATED WITH A SHORTWAVE TROUGH LOCATED OVER
OKLAHOMA EARLY THIS AFTERNOON ACCORDING TO WATER VAPOR SATELLITE
IMAGERY. HOWEVER DUE TO THE POSITION OF THE SHORTWAVE
TROUGH...THINK THAT THE EFFECTS OF DYNAMIC LIFT ON OUR MID-LEVEL
LAPSE RATES HAVE ALREADY OCCURRED. AS A RESULT...LEFT
PRECIPITATION ALONG THE FRONT THUNDERSTORM FREE THROUGH TONIGHT.
WILL CERTAINLY CONTINUE TO MONITOR AIRCRAFT OBSERVATIONS THROUGH
THIS EVENING...AND WILL UPDATE THE FORECAST IF IT LOOKS LIKE
THUNDER IS BECOMING MORE LIKELY.
SATURDAY...THE COLD FRONT IS EXPECTED TO MOVE ACROSS THE ENTIRE
FORECAST AREA BY SATURDAY MORNING...LEAVING COOLER AND MUCH DRIER
AIR IN PLACE ACROSS THE REGION. ALTHOUGH THE COLD FRONT DOES NOT
REPRESENT A STRONG CANADIAN AIRMASS...AFTER TODAY`S TEMPERATURES
IN THE MID TO UPPER 70S...IT WILL CERTAINLY BE NOTICEABLY COOLER
TOMORROW BEHIND THE FRONT. HIGHS ARE EXPECTED TO TOP OUT NEAR 60
DEGREES FOR MOST LOCATIONS...VERY CLOSE TO NORMAL HIGHS FOR THIS
TIME OF YEAR. BETWEEN LOW-LEVEL DRY AIR ADVECTION BEHIND THE FRONT
AND SHORTWAVE RIDGING ALOFT...MAINTAINED A DRY FORECAST FOR
SATURDAY.
SUNDAY...A RELATIVELY FAST MOVING SHORTWAVE TROUGH...CURRENTLY
LOCATED ABOUT 800 MILES WEST OF BAJA CALIFORNIA...IS EXPECTED TO
MOVE OVER THE SOUTHERN PLAINS SUNDAY AFTERNOON. WITH A LOW-LEVEL
COOL AIRMASS STILL IN PLACE ACROSS THE CWA BEHIND TODAY`S
FRONT...ALL MODEL GUIDANCE INDICATES THAT THIS SHORTWAVE TROUGH
WILL RESULT IN STRONG WARM AIR ADVECTION OVER THE CWA ON SUNDAY.
WARM AIR ADVECTION OVER THE COOL LOW-LEVEL AIRMASS DOES REPRESENT
PERSISTENT LIFT...HOWEVER PRECIPITATION PROSPECTS FOR THE REGION
LOOK VERY LIMITED AT THIS TIME. DESPITE NEARLY ALL MODELS SHOWING
THE PERSISTENT LIFT ON SUNDAY...THE PROSPECTS FOR MOISTURE RETURN
LOOK VERY LIMITED...AND FOCUSED ON LOCATIONS JUST WEST AND SOUTH
OF THE CWA. AS A RESULT...WENT AHEAD AND BUMPED POPS DOWN 10
PERCENT ACROSS THE ENTIRE AREA THROUGHOUT THE DAY ON SUNDAY.
THINK THAT OUR BEST CHANCES FOR LIGHT RAINFALL MAY BE WHEN THE
SHORTWAVE TROUGH MOVES DIRECTLY OVERHEAD SUNDAY AFTERNOON. MODELS
SHOW A BAND OF RELATIVELY STRONG MID-LEVEL FRONTOGENETIC FORCING
MOVING OVER THE CWA RIGHT OUT AHEAD OF THE SHORTWAVE ON SUNDAY.
THIS WILL LIKELY RESULT IN SOME ELEVATED PRECIPITATION...HOWEVER
THE LOW-LEVEL AIRMASS LOOKS DRY ENOUGH THAT MOST OF THIS SHOULD
EVAPORATE BEFORE REACHING THE SURFACE. AT ANY RATE...THE END
RESULT WAS THAT ISOLATED RAIN SHOWERS WERE INCLUDED IN THE
FORECAST EVEN WHERE POPS ARE AS LOW AS 10 PERCENT TO ACCOUNT FOR
THIS VIRGA/LIGHT RAIN POTENTIAL.
MONDAY INTO TUESDAY...IN GENERAL...A REINFORCING SHOT OF COOL AND
DRY AIR WILL BUILD INTO THE AREA BEHIND SUNDAY`S SHORTWAVE TROUGH
KEEPING US DRY ACROSS NORTH TEXAS FOR EARLY NEXT WEEK. THE LARGE
SCALE UPPER AIR PATTERN IS EXPECTED TO BE DOMINATED BY LARGE
TROUGHS OVER THE FAR EAST AND WEST COASTS...RESULTING IN BROAD
RIDGING OR NEARLY ZONAL FLOW OVER THE CENTRAL PORTION OF THE
COUNTRY. THIS PATTERN ALSO GENERALLY FAVORS DRY WEATHER FOR THE
CWA...HOWEVER PERSISTENT WESTERLY FLOW ALOFT OVER THE CONUS
ROCKIES WILL RESULT IN LEE-SIDE TROUGHING INCREASING IN INTENSITY
THROUGHOUT THE WEEK. WITH LEE-SIDE TROUGHING DEVELOPING AND A COOL
AIRMASS IN PLACE...WE WILL ONCE AGAIN HAVE A SITUATION WHERE WE
HAVE SOUTHERLY FLOW ALOFT IMPINGING ON A COOL LOW-LEVEL AIRMASS
NEAR THE SURFACE. THIS WILL RESULT IN PERSISTENT...ALBEIT
WEAK...LIFT AND MOISTURE RETURN BY TUESDAY AFTERNOON. BACKED OFF
ON POPS A BIT FROM THE PREVIOUS FORECAST ON TUESDAY...HOWEVER
MAINTAINED SOME 20 POPS OVER THE FAR WESTERN CWA TUESDAY
AFTERNOON...NEAREST TO THE LOW-LEVEL MOISTURE RETURN CONSISTENTLY
ADVERTISED IN MEDIUM RANGE GUIDANCE.
WEDNESDAY...MODELS ADVERTISE THAT THE UPPER LEVEL PATTERN WILL
AMPLIFY WITH RIDGING BUILDING OVER THE CONUS ROCKIES IN RESPONSE
TO A STRONG UPPER TROUGH BUILDING EASTWARD...FARTHER ON SHORE THE
WESTERN CONUS COAST. THIS RESULTS IN NORTHWEST FLOW ALOFT OVER THE
REGION ON WEDNESDAY...IN WHICH MODELS HAVE BEEN CONSISTENTLY
SENDING A STRONG BUT COMPACT SHORTWAVE TROUGH SOUTHEAST THROUGH
THE CWA OVER THE PAST COUPLE OF DAYS. THIS TROUGH IS EXPECTED TO
REMAIN WELL NORTH OF NORTH TEXAS...BUT SHOULD HELP SPREAD SOME OF
THE MOISTURE RETURN FROM WEST TEXAS EASTWARD OVER THE CWA ON
WEDNESDAY. IF MOISTURE DOES SPREAD EAST AS ADVERTISED AND LOW-
LEVEL WARM AIR ADVECTION AND ISENTROPIC LIFT CONTINUES... LIGHT
RAIN SHOWERS WILL LIKELY SPREAD ACROSS THE ENTIRE CWA ON
WEDNESDAY. BECAUSE LIFT IS EXPECTED TO REMAIN WEAK...RAIN SHOWERS
SHOULD BE SPOTTY/HIT-AND-MISS ON WEDNESDAY.
THURSDAY AND FRIDAY...MODELS INDICATE THAT LOW-LEVEL WARM AIR
ADVECTION PERSISTS...HOWEVER MODELS ARE ALSO BRINGING THE UPPER
LEVEL RIDGE OUT FROM THE CONUS ROCKIES AND OVER THE GREAT PLAINS
FOR THE LATTER PART OF THE WEEK. DESPITE PERSISTENT LOW-LEVEL
LIFT...WILL FAVOR THE UPPER LEVEL RIDGING IN THIS FORECAST AND
KEEP THURSDAY AND FRIDAY DRY FOR NOW AS MID AND UPPER LEVEL
FORCING SHOULD BE DOMINATED BY SUBSIDENCE.
NEXT WEEKEND...MODELS ARE DEFINITELY STRUGGLING WITH RUN TO RUN
AND MODEL TO MODEL CONSISTENCY WITH REGARDS TO THE EVOLUTION OF
THE STRONG WEST COAST UPPER TROUGH. HOWEVER...MODELS HAVE BEEN
CONSISTENTLY BRINGING THIS TROUGH OVER THE PLAINS NEXT
WEEKEND...WHICH MAY RESULT IN SOME DECENT RAIN CHANCES FOR THE
REGION. THIS IS CURRENTLY BEYOND THE VALID FORECAST PERIOD...BUT
IT IS A SYSTEM THAT WE WILL BE KEEPING A CLOSE EYE ON IN THE
COMING DAYS.
CAVANAUGH
&&
.AVIATION...
/ISSUED 1137 AM CST FRI DEC 5 2014/
CONCERNS...RETURN OF MVFR TO IFR CONDITIONS LATE TONIGHT BEHIND A
COLD FRONT.
A SLOT OF WARM...DRY AIR TO THE WEST IS PUSHING INTO THE
METROPLEX AND SHOULD ALLOW MVFR CIGS TO CONTINUE INCREASING WITH A
PERIOD OF VFR SKIES DURING THE MID/LATE AFTERNOON AND EVENING
HOURS. KACT MAY NOT FAIR AS GOOD THIS AFTERNOON...BUT COULD SEE
VFR SKIES THIS EVENING THROUGH MIDNIGHT.
A COLD FRONT EXTENDING FROM NORTH OF KTUL TO SOUTH OF KLBB AT 17Z
WILL MOVE ACROSS THE METROPLEX SITES THIS EVENING 01 TO 02Z AND
THROUGH KACT AROUND 05Z. EXPECT WINDS TO BE SOUTH-SOUTHWEST 10-15
KNOTS AHEAD OF THE FRONT THEN NORTH 10-14 KNOTS OVERNIGHT AND ON
SATURDAY.
THERE IS A SLIGHT CHANCE OF SHOWERS THIS AFTERNOON AND
EVENING...BUT COVERAGE WILL BE LOW AND WILL NOT INCLUDE IN THE
MIDDAY TAFS. LOW LEVEL MOISTURE BEHIND THE FRONT WILL AGAIN LOWER
CIGS TO MVFR 1000-1300 FEET WITH A POTENTIAL FOR IFR CIGS AND MVFR
VIS FROM AROUND DAYBREAK THROUGH MID MORNING. CIGS SHOULD RETURN
TO VFR AROUND MIDDAY SATURDAY AND CONTINUE THROUGH THE AFTERNOON.
75
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 50 61 44 57 43 / 10 5 5 10 10
WACO, TX 51 63 46 57 43 / 30 10 10 20 20
PARIS, TX 49 60 42 56 39 / 30 10 5 10 10
DENTON, TX 46 60 42 56 41 / 10 5 5 10 5
MCKINNEY, TX 48 60 42 57 40 / 20 5 5 10 10
DALLAS, TX 50 61 45 56 44 / 20 5 5 10 10
TERRELL, TX 52 62 44 58 40 / 30 5 5 10 10
CORSICANA, TX 53 63 45 59 43 / 30 10 10 20 20
TEMPLE, TX 50 64 46 58 44 / 30 10 10 20 20
MINERAL WELLS, TX 44 60 42 56 42 / 10 5 10 20 10
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
544 AM CST FRI DEC 5 2014
.DISCUSSION...
SEE THE 12Z AVIATION DISCUSSION BELOW.
40
&&
.AVIATION...
SEA FOG AND LOW STRATUS WILL PERSIST THROUGH THE MID AND LATE
MORNING PERIOD. THE NAM AND RAP MODELS LIFT THE LIFR/IFR CEILINGS
TO MVFR THIS AFTERNOON OVER THE INLAND SITES...AND KCLL AND KUTS
MAY EXPERIENCE A BREAK THROUGH TO VFR. HOWEVER...KGLS AND KLBX MAY
EXPERIENCE IFR TO LIFR IF THE SEA FOG PERSISTS OR ONLY BREAKS FOR
A SHORT PERIOD DURING THE AFTERNOON. THE MODELS LOWER CONDITIONS
TONIGHT.
ON TOP OF THE CEILING AND VISIBILITY PROBLEMS...A SHORTWAVE TROUGH
ALOFT WILL MOVE ACROSS THE AREA AND PROVIDE SHOWERS AT LEAST
THROUGH MID MORNING. THE MODELS DEVELOP AND MOVE ANOTHER SHORTWAVE
TROUGH ACROSS SE TX TONIGHT.
40
&&
.PREV DISCUSSION... /ISSUED 417 AM CST FRI DEC 5 2014/
DISCUSSION...
DENSE FOG CONTINUES TO COVER PARTS OF SE TX. SFC WINDS HAVE
INCREASED OVER THE WESTERN ZONES AND THIS APPEARS TO BE MITIGATING
THE FOG THREAT FROM KARM TO KCLL. WILL KEEP A DENSE FOG ADVISORY
IN EFFECT FOR FOR MAINLY THE SOUTHERN HALF OF THE CWA THROUGH 15Z.
VISIBILITIES WILL FLUCTUATE THIS MORNING AS BANDS OF SHOWERS MOVE
THROUGH. IF DRIVING THIS MORNING...BE PREPARED FOR RAPIDLY
CHANGING VISIBILITIES. SCATTERED SHOWERS ARE ALSO DEVELOPING AS A
WEAK S/WV OVER SE COLORADO PUSHES EAST ACROSS THE SOUTHERN PLAINS.
FCST SOUNDINGS SHOW PW VALUES NEAR 1.40 INCHES TODAY BUT THE
MOISTURE PROFILE IS ONLY SATURATED TO AROUND 900 MB WITH MUCH
DRIER AIR ALOFT. SHORT TERM MODELS DON`T SHOW MUCH IN THE WAY OF
PRECIP TODAY BUT RECENT RADAR TRENDS WOULD BEG TO DIFFER. RADAR
COVERAGE CONTINUES TO EXPAND SO BUMPED POPS INTO THE 40S OVER THE
CENTRAL ZONES WITH LESSER VALUES TOWARD THE COAST AND TO THE
NORTH. PRECIP IS EXPECTED TO WANE IN THE AFTN AS THE S/WV PUSHES
EAST.
LOW PRESSURE DEVELOPING OVER THE TEXAS PANHANDLE WILL GRADUALLY
STRENGTHEN AS IT MOVES E-NE TONIGHT AND SATURDAY. AS THE LOW
EXITS THE REGION...IT WILL DRAG A COLD FRONT ACROSS SE TX LATE
SATURDAY AFTN. THE FRONT WILL TRIGGER AN ADDITIONAL ROUND OF
SHRA/TSRA. YET ANOTHER S/WV WILL MOVE ACROSS THE STATE ON SUNDAY.
THE NAM AND GFS ARE CONSIDERABLY STRONGER AND FURTHER SOUTH WITH
THIS FEATURE THAN THE MORE BENIGN ECMWF. WILL MAINTAIN CHANCE
POPS OVER THE NORTH ON SUNDAY AND SLT CHANCE TOWARD THE COAST.
THIS ACTIVE WEATHER PATTERN WILL CONTINUE INTO THE MIDDLE OF NEXT
WEEK WITH YET ANOTHER S/WV TROUGH MOVING INTO THE STATE. THE
TROUGH WILL GET SHEARED OUT AS IT APPROACHES EAST TEXAS BUT WILL
THERE SHOULD BE ENOUGH LIFT ASSOCIATED WITH THE TROUGH TO GENERATE
A FEW SHOWERS OVER SE TX. WILL MAINTAIN THE 20 POPS CURRENTLY IN
THE GRIDS. 43
MARINE...
AREAS OF DENSE SEA FOG SHOULD PERSIST FOR MOST OF THE MORNING. THE
MODELS ARE FORECASTING MORE SOUTHERLY WINDS TO DEVELOP. EVEN WITH
DEWPOINTS IN THE 60S MOVING OVER THE COOLER SHELF WATERS...THE
SOUTHERN WINDS SHOULD SHORTEN THE FETCH ENOUGH FOR THE FOG TO LIFT
ABOVE ONE MILE. BECAUSE OF THE WINDS...THE SEA FOG MAY BE MORE
PATCHY LATER TODAY. THERE WILL BE ANOTHER ROUND OF FOG TONIGHT AS A
FRONT APPROACHES FROM THE NORTHWEST. THIS FRONT IS FORECAST BY THE
MODELS TO WORK ITS WAY OFF THE COAST ON SATURDAY MORNING.
THE FOG FORECAST IS TRICKIER FOR NEXT WEEK. WINDS ON SUNDAY DO
SWITCH BACK AROUND TO THE EAST BUT THE AIRMASS APPEARS THAT IT WILL
BE TOO DRY. THINGS MAY BECOME MORE CONDUCIVE FOR SEA FOG FORMATION
BY THE MIDDLE OF THE WEEK.
40
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 76 61 68 52 61 / 30 30 20 10 30
HOUSTON (IAH) 76 64 73 55 64 / 40 30 30 20 20
GALVESTON (GLS) 69 64 70 58 63 / 20 20 30 20 20
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...DENSE FOG ADVISORY UNTIL 9 AM CST THIS MORNING FOR THE FOLLOWING
ZONES: AUSTIN...BRAZORIA...CHAMBERS...COLORADO...FORT
BEND...GALVESTON...HARRIS...JACKSON...LIBERTY...MATAGORDA...
MONTGOMERY...WALLER...WASHINGTON...WHARTON.
GM...DENSE FOG ADVISORY UNTIL 11 AM CST THIS MORNING FOR THE
FOLLOWING ZONES: GALVESTON BAY...MATAGORDA BAY...WATERS
FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT 20 NM...
WATERS FROM HIGH ISLAND TO FREEPORT OUT 20 NM.
&&
$$
DISCUSSION...43
AVIATION/MARINE...40
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1145 PM CST THU DEC 4 2014
.DISCUSSION...
06Z AVIATION DISCUSSION BELOW.
&&
.AVIATION...
AREAWIDE SOUTHERN 2/3RDS OF SE TX IFR WITH FAR INLAND TERMINALS
NOT FAR BEHIND IN REACHING THIS CATEGORY. NEARSHORE GULF SEA FOG
DEVELOPMENT HAS LOWERED MANY SOUTHERN HUBS TO NEAR VLIFR...OR LOW
END LIFR. A NEAR STATIONARY WARM FRONTAL BOUNDARY DRAPED NEAR THE
COAST WILL LIFT NORTHWARD THROUGH THE MORNING HOURS AND WASH OUT
FAR INLAND THROUGH FRIDAY AFTERNOON. AS THIS OCCURS...EAST WINDS
BEHIND THE BOUNDARY WILL VEER SOUTHERLY AND SLIGHTLY STRENGTHEN.
THIS WILL AID IN SCOURING OUT THE LIFR TO IFR CEILINGS/FOG TO MVFR
(OR BRIEF VFR) UNTIL TEMPERATURES COOL BACK INTO THE 60S AND DEW
POINT SPREADS NARROW...ULTIMATELY LOWERING CATS BACK DOWN TO LOW
END MVFR TO IFR GOING INTO SATURDAY MORNING. 31
&&
.PREV DISCUSSION... /ISSUED 1131 PM CST THU DEC 4 2014/
UPDATE...
HAVE GONE AHEAD AND EXPANDED THE DENSE FOG ADVISORY FURTHER NORTH
TOWARDS A LIBERTY TO MONTGOMERY TO AUSTIN COUNTY LINE.
VISIBILITIES HAVE CONTINUED TO QUICKLY DETERIORATE THIS EVENING
WITH MULTIPLE SITES ALREADY AT 1/2 A MILE. VISIBILITIES ARE ONLY
EXPECTED TO LESSEN THROUGH THE NIGHT INTO TOMORROW MORNING. NEW
ZONES OUT SHORTLY. 23
PREV DISCUSSION... /ISSUED 904 PM CST THU DEC 4 2014/
UPDATE...
SEE DISCUSSION FOR EVENING UPDATE.
DISCUSSION...
LOW LIGHT VIS SHOWING A PLETHORA OF CLOUDS AROUND THE AREA THIS
EVENING WITH ALSO SOME LIGHT RETURNS ON THE RADAR. GPS MET SITE
SHOWING MOISTURE VALUES RUNNING AROUND ~1.55" WHICH IS ABOUT +2 SD
FOR THIS TIME OF YEAR. MAIN FORECAST ISSUE FOR THIS UPDATE WILL BE
THE CHANCE OF DENSE FOG. CURRENT WEBCAMS FROM GALVESTON SHOWS SEA
FOG RIGHT OFF THE COAST WITH SOME CAMERAS SHOWING HEAVY FOG.
SURFACE ANALYSIS REVEALS EASTERLY WINDS OVER THE WATERS WHICH
SHOULD HELP TO ADVECT THE SEA FOG INLAND. WINDS ARE THEN
FORECASTED TO TURN FROM THE SOUTHEAST WHICH SHOULD REALLY HELP TO
ADVECT THE FOG INLAND. SREF AND NAM DEWPOINT DEPRESSION FIELDS
ALONG WITH HRRR VIS PRODUCT ALL SHOWING FOG MOVING INLAND TONIGHT.
DUE TO THIS WILL KEEP DENSE FOG ADVISORY WITH CURRENT
CONFIGURATION. FOR NOW HAVE ADDED AREAS OF FOG INLAND AND LEFT
MENTION OF DENSE CLOSER TO THE COAST. HAVE ALSO BROUGHT DOWN HIGH
TEMPERATURES A DEGREE OR SO TOMORROW GIVEN THE CLOUDS IN THE
FORECAST SOUNDING. THE NEXT FORECAST PACKAGE WITH HAVE TO
CAREFULLY WATCH THIS THOUGH AS 850 TEMPS ARE AROUND 14 C WHICH IS
PRETTY WARM. 23
PREV DISCUSSION... /ISSUED 621 PM CST THU DEC 4 2014/
DISCUSSION...
00Z AVIATION DISCUSSION BELOW.
AVIATION...
VEERING LIGHT EASTERLIES WILL AID IN ALLOWING A WEAK WARM FRONT
TO ADVANCE INLAND TOMORROW. A SOUPY ENVIRONMENT WITH MANY SITES
ALREADY FALLING INTO IFR (INTERIOR) TO LIFR (COASTAL) CATEGORICAL
CEILINGS WITH DETERIORATING VISIBILITIES WITHIN INLAND HAZE/-SHRA
OR DUE TO BEING ON THE NORTHERN FRINGES OF SEA FOG ALONG THE COAST.
IF SEA FOG FORMS OVER MORE WIDESPREAD SHALLOWER NEARSHORE GULF AND
BAY WATERS...THERE IS A CHANCE THAT IT WILL ADVECT INLAND AND TANK
DECKS/VSBYS TO V-LIFR THROUGH MID TO LATE FRIDAY MORNING. IF THIS
SCENARIO DOES NOT MATERIALIZE...A LIGHT EAST-SOUTHEAST BREEZE MAY
MIX OUT LOWER LAYERS ENOUGH TO KEEP MANY IN THE IFR RANGE. FRIDAY
AFTERNOON SCATTERING OUT BEHIND THIS WEAK WARM FRONTAL BOUNDARY...
WITH PERIODIC WAA SHOWERS OR LIGHT DRIZZLE PASSING THROUGH FROM
LATE MORNING THROUGH THE EARLY EVENING HOURS. ALL AND ALL...MAJORITY
OF PERIOD WILL BE MVFR OR LOWER WITH BRIEF BREAKS TO VFR (IN TANDEM
WITH SLIGHTLY STRENGTHENED SOUTHERLIES) DEPENDENT UPON INLAND FRONTAL
MOVEMENT. 31
PREV DISCUSSION... /ISSUED 338 PM CST THU DEC 4 2014/
DISCUSSION...
21Z OBS AND VIS SATELLITE STILL CONFIRM A LAYER OF SEA FOG
STRETCHING FROM OFFSHORE SABINE PASS THROUGH GALVESTON BAY AND
ADJACENT WATERS. THERE ARE SOME PATCHES OF DENSE FOG IN THE GULF
AND WITH EASTERLY LOW LEVEL WINDS...FOG SHOULD ADVECTION INTO THE
COASTAL COUNTIES TONIGHT INTO FRI MORNING. LATEST RUNS OF THE
RAPID REFRESH SUPPORT THIS IDEA SO WILL KEEP DENSE FOG ADVISORY IN
EFFECT AS IS FOR BOTH THE COASTAL COUNTIES AND UPPER TX COASTAL
WATERS. WINDS SHOULD TURN SOUTHERLY TOMORROW SO EXPECT FOG TO
BREAK UP MORE SO THAN TODAY. BUT FOG MAY RETURN FRI NIGHT INTO SAT
MORNING AS A FRONT APPROACHES THE AREA. WINDS MAY DECREASE OR
BECOME MORE EASTERLY WHICH WILL SUPPORT FOG DEVELOPMENT.
UPPER AIR ANALYSIS AT 500MB FOR 12Z SHOWED A STRONG SHORTWAVE
TROUGH MOVING THROUGH S CALIFORNIA. WATER VAPOR IMAGERY HAS THIS
DISTURBANCE ALREADY MOVING ACROSS THE S ROCKIES. MODELS IN GOOD
AGREEMENT WITH SYSTEM REACHING C PLAINS BY 12Z FRI AND HAVING IT
SHEAR OUT A BIT. AS THE SHORTWAVE PUSHES INTO THE OHIO RIVER
VALLEY FRI NIGHT INTO SATURDAY...A COLD FRONT SHOULD BEGIN TO PUSH
INTO THE AREA. THE FRONT WILL SLOWLY PUSH INTO THE AREA AND BE THE
FOCUS FOR SOME SHOWERS PERHAPS AN ISO THUNDERSTORM. MODELS HAVE
BACKED OFF ON RAIN CHANCES AND AGREE WITH THIS TREND. FORECAST
WILL KEEP MAINLY 20/30 POPS FOR FRI/SAT TIME FRAME WITH THE FRONT
COMING INTO THE AREA. THE FRONT WILL BE SLOW MOVING SO IT MAY TAKE
A WHILE FOR ANY FOG/SEA FOG TO ERODE LATE SAT INTO SUN. THERE
SHOULD BE ENOUGH DRIER AIR TO MIX OUT THE FOG DURING THIS TIME.
FORECAST WILL ALSO CARRY 20/30 POPS INTO SUNDAY AS A SECOND SHORT
WAVE TROUGH MOVES ACROSS THE AREA. THERE IS STILL SOME
DISAGREEMENT BETWEEN NAM/GFS/ECMWF ON THE STRENGTH OF THE SYSTEM
AND THE NAM IS SIGNIFICANTLY FARTHER SOUTH WITH THE SYSTEM. BUT
CONDITIONS SHOULD BEGIN TO DRY OUT MON AS HIGH PRESSURE BUILDS
INTO THE AREA FROM THE PLAINS.
UPPER LEVEL FLOW MON/TUE IS A BIT MORE ZONAL PER GFS/ECMWF BUT
BECOMES MUCH MORE AMPLIFIED BY MID WEEK ESPECIALLY THE ECMWF.
ECMWF HAS A MUCH STRONGER SYSTEM OVER THE MID ATLANTIC WHERE THE
GFS IS MORE PROGRESSIVE. GIVEN RECENT PATTERNS THINK THE ECMWF IS
MORE ON THE RIGHT TRACK AND HAS SOME SUPPORT FROM PREVIOUS
CANADIAN MODEL RUNS. WITH THIS IN MIND...THERE SHOULD BE A DAY OR
TWO PRECIP FREE BUT MAY GET RAIN CHANCES BACK LATE WED INTO THUR
AS A WEAK DISTURBANCE MOVES INTO TX UNDERNEATH AN AMPLIFYING
RIDGE. MODELS HAVE TRENDED COLDER WITH TEMPERATURES AS WELL SO
THINK LATEST CONSENSUS BLEND LOOKS GOOD FOR EXTENDED FORECAST
TEMPS WITH SOME MORE WEIGHT ON THE ECMWF. 39
MARINE...
AFTER A BRIEF PERIOD OF IMPROVEMENT IN FOG REDUCED VISIBILITIES
THE FOG IS AGAIN BEGINNING TO THICKEN. WILL MAINTAIN THE MARINE
DENSE FOG ADVISORY AS IS THROUGH 12Z BUT MAY NEED A FEW HOURS
EXTENSION FOR THE GALVESTON BAY AREA AS IT WILL BE THE LAST TO
FEEL THE IMPACTS OF THE WARM FRONT AND HAS THE COOLER WATERS
FRIDAY MORNING. OTHERWISE LITTLE CHANGE TO THE FORECAST. WINDS
RELAX BEFORE THE FRONT ARRIVES SO SOME THREAT FOR SEA/RADIATION
FOG AGAIN EARLY SATURDAY. WEAK COLD FRONT LATE SATURDAY AFTERNOON
OR MORE LIKELY EVENING TO CLEAR THE NEARSHORE WATERS. A BRIEF
STINT OF SCEC WINDS MAY DEVELOP POST FRONTAL BUT FOR NOW WILL KEEP
IT CLOSER TO 15 KNOTS. NORTHEAST FLOW GRADUALLY TURNS MORE
EASTERLY MONDAY AND BY MONDAY NIGHT OR PERHAPS TUESDAY THE FOG
THREAT BEGINS TO RISE AGAIN. 45
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 63 76 58 68 51 / 20 30 30 20 10
HOUSTON (IAH) 63 75 63 72 54 / 20 30 30 30 20
GALVESTON (GLS) 63 69 63 69 58 / 20 20 20 30 20
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...DENSE FOG ADVISORY UNTIL 9 AM CST FRIDAY FOR THE FOLLOWING
ZONES: AUSTIN...BRAZORIA...CHAMBERS...COLORADO...FORT
BEND...GALVESTON...HARRIS...JACKSON...LIBERTY...MATAGORDA...
MONTGOMERY...WALLER...WHARTON.
GM...DENSE FOG ADVISORY UNTIL 9 AM CST FRIDAY FOR THE FOLLOWING
ZONES: GALVESTON BAY...MATAGORDA BAY...WATERS FROM FREEPORT
TO THE MATAGORDA SHIP CHANNEL 20 NM TO 60 NM...WATERS FROM
FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS
FROM HIGH ISLAND TO FREEPORT 20 TO 60 NM...WATERS FROM HIGH
ISLAND TO FREEPORT OUT 20 NM.
&&
$$
DISCUSSION...23
AVIATION/MARINE...31
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1131 PM CST THU DEC 4 2014
.UPDATE...
HAVE GONE AHEAD AND EXPANDED THE DENSE FOG ADVISORY FURTHER NORTH
TOWARDS A LIBERTY TO MONTGOMERY TO AUSTIN COUNTY LINE.
VISIBILITIES HAVE CONTINUED TO QUICKLY DETERIORATE THIS EVENING
WITH MULTIPLE SITES ALREADY AT 1/2 A MILE. VISIBILITIES ARE ONLY
EXPECTED TO LESSEN THROUGH THE NIGHT INTO TOMORROW MORNING. NEW
ZONES OUT SHORTLY. 23
&&
.PREV DISCUSSION... /ISSUED 904 PM CST THU DEC 4 2014/
UPDATE...
SEE DISCUSSION FOR EVENING UPDATE.
DISCUSSION...
LOW LIGHT VIS SHOWING A PLETHORA OF CLOUDS AROUND THE AREA THIS
EVENING WITH ALSO SOME LIGHT RETURNS ON THE RADAR. GPS MET SITE
SHOWING MOISTURE VALUES RUNNING AROUND ~1.55" WHICH IS ABOUT +2 SD
FOR THIS TIME OF YEAR. MAIN FORECAST ISSUE FOR THIS UPDATE WILL BE
THE CHANCE OF DENSE FOG. CURRENT WEBCAMS FROM GALVESTON SHOWS SEA
FOG RIGHT OFF THE COAST WITH SOME CAMERAS SHOWING HEAVY FOG.
SURFACE ANALYSIS REVEALS EASTERLY WINDS OVER THE WATERS WHICH
SHOULD HELP TO ADVECT THE SEA FOG INLAND. WINDS ARE THEN
FORECASTED TO TURN FROM THE SOUTHEAST WHICH SHOULD REALLY HELP TO
ADVECT THE FOG INLAND. SREF AND NAM DEWPOINT DEPRESSION FIELDS
ALONG WITH HRRR VIS PRODUCT ALL SHOWING FOG MOVING INLAND TONIGHT.
DUE TO THIS WILL KEEP DENSE FOG ADVISORY WITH CURRENT
CONFIGURATION. FOR NOW HAVE ADDED AREAS OF FOG INLAND AND LEFT
MENTION OF DENSE CLOSER TO THE COAST. HAVE ALSO BROUGHT DOWN HIGH
TEMPERATURES A DEGREE OR SO TOMORROW GIVEN THE CLOUDS IN THE
FORECAST SOUNDING. THE NEXT FORECAST PACKAGE WITH HAVE TO
CAREFULLY WATCH THIS THOUGH AS 850 TEMPS ARE AROUND 14 C WHICH IS
PRETTY WARM. 23
PREV DISCUSSION... /ISSUED 621 PM CST THU DEC 4 2014/
DISCUSSION...
00Z AVIATION DISCUSSION BELOW.
AVIATION...
VEERING LIGHT EASTERLIES WILL AID IN ALLOWING A WEAK WARM FRONT
TO ADVANCE INLAND TOMORROW. A SOUPY ENVIRONMENT WITH MANY SITES
ALREADY FALLING INTO IFR (INTERIOR) TO LIFR (COASTAL) CATEGORICAL
CEILINGS WITH DETERIORATING VISIBILITIES WITHIN INLAND HAZE/-SHRA
OR DUE TO BEING ON THE NORTHERN FRINGES OF SEA FOG ALONG THE COAST.
IF SEA FOG FORMS OVER MORE WIDESPREAD SHALLOWER NEARSHORE GULF AND
BAY WATERS...THERE IS A CHANCE THAT IT WILL ADVECT INLAND AND TANK
DECKS/VSBYS TO V-LIFR THROUGH MID TO LATE FRIDAY MORNING. IF THIS
SCENARIO DOES NOT MATERIALIZE...A LIGHT EAST-SOUTHEAST BREEZE MAY
MIX OUT LOWER LAYERS ENOUGH TO KEEP MANY IN THE IFR RANGE. FRIDAY
AFTERNOON SCATTERING OUT BEHIND THIS WEAK WARM FRONTAL BOUNDARY...
WITH PERIODIC WAA SHOWERS OR LIGHT DRIZZLE PASSING THROUGH FROM
LATE MORNING THROUGH THE EARLY EVENING HOURS. ALL AND ALL...MAJORITY
OF PERIOD WILL BE MVFR OR LOWER WITH BRIEF BREAKS TO VFR (IN TANDEM
WITH SLIGHTLY STRENGTHENED SOUTHERLIES) DEPENDENT UPON INLAND FRONTAL
MOVEMENT. 31
PREV DISCUSSION... /ISSUED 338 PM CST THU DEC 4 2014/
DISCUSSION...
21Z OBS AND VIS SATELLITE STILL CONFIRM A LAYER OF SEA FOG
STRETCHING FROM OFFSHORE SABINE PASS THROUGH GALVESTON BAY AND
ADJACENT WATERS. THERE ARE SOME PATCHES OF DENSE FOG IN THE GULF
AND WITH EASTERLY LOW LEVEL WINDS...FOG SHOULD ADVECTION INTO THE
COASTAL COUNTIES TONIGHT INTO FRI MORNING. LATEST RUNS OF THE
RAPID REFRESH SUPPORT THIS IDEA SO WILL KEEP DENSE FOG ADVISORY IN
EFFECT AS IS FOR BOTH THE COASTAL COUNTIES AND UPPER TX COASTAL
WATERS. WINDS SHOULD TURN SOUTHERLY TOMORROW SO EXPECT FOG TO
BREAK UP MORE SO THAN TODAY. BUT FOG MAY RETURN FRI NIGHT INTO SAT
MORNING AS A FRONT APPROACHES THE AREA. WINDS MAY DECREASE OR
BECOME MORE EASTERLY WHICH WILL SUPPORT FOG DEVELOPMENT.
UPPER AIR ANALYSIS AT 500MB FOR 12Z SHOWED A STRONG SHORTWAVE
TROUGH MOVING THROUGH S CALIFORNIA. WATER VAPOR IMAGERY HAS THIS
DISTURBANCE ALREADY MOVING ACROSS THE S ROCKIES. MODELS IN GOOD
AGREEMENT WITH SYSTEM REACHING C PLAINS BY 12Z FRI AND HAVING IT
SHEAR OUT A BIT. AS THE SHORTWAVE PUSHES INTO THE OHIO RIVER
VALLEY FRI NIGHT INTO SATURDAY...A COLD FRONT SHOULD BEGIN TO PUSH
INTO THE AREA. THE FRONT WILL SLOWLY PUSH INTO THE AREA AND BE THE
FOCUS FOR SOME SHOWERS PERHAPS AN ISO THUNDERSTORM. MODELS HAVE
BACKED OFF ON RAIN CHANCES AND AGREE WITH THIS TREND. FORECAST
WILL KEEP MAINLY 20/30 POPS FOR FRI/SAT TIME FRAME WITH THE FRONT
COMING INTO THE AREA. THE FRONT WILL BE SLOW MOVING SO IT MAY TAKE
A WHILE FOR ANY FOG/SEA FOG TO ERODE LATE SAT INTO SUN. THERE
SHOULD BE ENOUGH DRIER AIR TO MIX OUT THE FOG DURING THIS TIME.
FORECAST WILL ALSO CARRY 20/30 POPS INTO SUNDAY AS A SECOND SHORT
WAVE TROUGH MOVES ACROSS THE AREA. THERE IS STILL SOME
DISAGREEMENT BETWEEN NAM/GFS/ECMWF ON THE STRENGTH OF THE SYSTEM
AND THE NAM IS SIGNIFICANTLY FARTHER SOUTH WITH THE SYSTEM. BUT
CONDITIONS SHOULD BEGIN TO DRY OUT MON AS HIGH PRESSURE BUILDS
INTO THE AREA FROM THE PLAINS.
UPPER LEVEL FLOW MON/TUE IS A BIT MORE ZONAL PER GFS/ECMWF BUT
BECOMES MUCH MORE AMPLIFIED BY MID WEEK ESPECIALLY THE ECMWF.
ECMWF HAS A MUCH STRONGER SYSTEM OVER THE MID ATLANTIC WHERE THE
GFS IS MORE PROGRESSIVE. GIVEN RECENT PATTERNS THINK THE ECMWF IS
MORE ON THE RIGHT TRACK AND HAS SOME SUPPORT FROM PREVIOUS
CANADIAN MODEL RUNS. WITH THIS IN MIND...THERE SHOULD BE A DAY OR
TWO PRECIP FREE BUT MAY GET RAIN CHANCES BACK LATE WED INTO THUR
AS A WEAK DISTURBANCE MOVES INTO TX UNDERNEATH AN AMPLIFYING
RIDGE. MODELS HAVE TRENDED COLDER WITH TEMPERATURES AS WELL SO
THINK LATEST CONSENSUS BLEND LOOKS GOOD FOR EXTENDED FORECAST
TEMPS WITH SOME MORE WEIGHT ON THE ECMWF. 39
MARINE...
AFTER A BRIEF PERIOD OF IMPROVEMENT IN FOG REDUCED VISIBILITIES
THE FOG IS AGAIN BEGINNING TO THICKEN. WILL MAINTAIN THE MARINE
DENSE FOG ADVISORY AS IS THROUGH 12Z BUT MAY NEED A FEW HOURS
EXTENSION FOR THE GALVESTON BAY AREA AS IT WILL BE THE LAST TO
FEEL THE IMPACTS OF THE WARM FRONT AND HAS THE COOLER WATERS
FRIDAY MORNING. OTHERWISE LITTLE CHANGE TO THE FORECAST. WINDS
RELAX BEFORE THE FRONT ARRIVES SO SOME THREAT FOR SEA/RADIATION
FOG AGAIN EARLY SATURDAY. WEAK COLD FRONT LATE SATURDAY AFTERNOON
OR MORE LIKELY EVENING TO CLEAR THE NEARSHORE WATERS. A BRIEF
STINT OF SCEC WINDS MAY DEVELOP POST FRONTAL BUT FOR NOW WILL KEEP
IT CLOSER TO 15 KNOTS. NORTHEAST FLOW GRADUALLY TURNS MORE
EASTERLY MONDAY AND BY MONDAY NIGHT OR PERHAPS TUESDAY THE FOG
THREAT BEGINS TO RISE AGAIN. 45
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 63 76 58 68 51 / 20 30 30 20 10
HOUSTON (IAH) 63 75 63 72 54 / 20 30 30 30 20
GALVESTON (GLS) 63 69 63 69 58 / 20 20 20 30 20
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...DENSE FOG ADVISORY UNTIL 9 AM CST FRIDAY FOR THE FOLLOWING
ZONES: AUSTIN...BRAZORIA...CHAMBERS...COLORADO...FORT
BEND...GALVESTON...HARRIS...JACKSON...LIBERTY...MATAGORDA...
MONTGOMERY...WALLER...WHARTON.
GM...DENSE FOG ADVISORY UNTIL 9 AM CST FRIDAY FOR THE FOLLOWING
ZONES: GALVESTON BAY...MATAGORDA BAY...WATERS FROM FREEPORT
TO THE MATAGORDA SHIP CHANNEL 20 NM TO 60 NM...WATERS FROM
FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS
FROM HIGH ISLAND TO FREEPORT 20 TO 60 NM...WATERS FROM HIGH
ISLAND TO FREEPORT OUT 20 NM.
&&
$$
DISCUSSION...23
AREA FORECAST DISCUSSION
NWS PORTLAND OR
242 PM PST FRI DEC 5 2014
.SYNOPSIS...A WETTER...WARMER AND BREEZIER STORM SYSTEM WILL ARRIVE
LATE TONIGHT AND PERSIST INTO SATURDAY. IT APPEARS INCREASINGLY LIKELY
THAT PRECIPITATION WILL INITIALLY FALL IN THE FORM OF FREEZING RAIN
IN THE UPPER HOOD RIVER VALLEY AND SHELTERED VALLEYS OF
THE SOUTH WASHINGTON CASCADES. HOWEVER...TEMPERATURES SHOULD WARM
ABOVE FREEZING IN THESE LOCATIONS SATURDAY MORNING. CONDITIONS
SHOULD THEN TEMPORARILY DRY OUT LATE SATURDAY INTO SUNDAY ACROSS THE
AREEA...BUT VALLEY FOG WILL LIKELY DEVELOP BY THE TIME MOST PEOPLE
WAKE UP SUNDAY MORNING. A SERIES OF WET STORM SYSTEMS WILL LIKELY
IMPACT THE AREA BEGINNING LATE SUNDAY...AND LASTING FOR
MUCH OF NEXT WEEK.
&&
.SHORT TERM...TONIGHT THROUGH MONDAY...A LOOP OF SATELLITE IMAGERY
SHOWS A COMPACT UPPER LEVEL LOW LIFTING EAST-NORTHEASTWARD TOWARDS
THE OREGON COAST. COOLING CLOUD TOPS ARE EVIDENT VIA INFRARED
SATELLITE IMAGERY...WITH LIGHTNING BEING DETECTED OFF THE SOUTHERN
OREGON COAST. THIS BAND OF SHOWERS AND ISOLATED THUNDERSTORMS WILL
LIFT NORTHEASTWARD ACROSS THE AREA TONIGHT. EXPECT A PERIOD OF HEAVIER
RAIN WHEN THIS FRONT MOVES ACROSS THE AREA TONIGHT. PRESSURE
GRADIENTS WILL TURN A LITTLE MORE SOUTHERLY SATURDAY MORNING SO THERE
MAY BE A PERIOD OF BREEZIER CONDITIONS LATE TONIGHT AND EARLY
SATURDAY MORNING IN THE WILLAMETTE VALLEY.
MEANWHILE...TEMPERATURES CONTINUE TO REMAIN BELOW FREEZING IN THE
UPPER HOOD RIVER VALLEY AND SHELTERED LOCATIONS IN EASTERN SKAMANIA
COUNTY...PRIMARILY BETWEEN 1000 AND 3000 FEET. IN FACT...A FEW
LOCATIONS IN THE NORTH OREGON CASCADES INCLUDING LOG CREEK RAWS AND
GREENPOINT SNOTEL HAVE COOLED SEVERAL DEGREES TODAY. GIVEN QPF
AMOUNTS WITH THE SYSTEM TONIGHT WILL LIKELY END UP IN THE QUARTER TO
HALF INCH RANGE IN THE UPPER HOOD RIVER VALLEY...AND EASTERN SKAMANIA
COUNTY...THERE IS SOME CONCERN A SECOND ROUND OF MAJOR ICING WILL
OCCUR OVERNIGHT. HOWEVER...HAVE OPTED TO GO WITH A FREEZING RAIN
ADVISORY FOR NOW FOR A COUPLE OF REASONS. FIRST...TEMPERATURES MAY
STILL MODIFY A BIT THIS AFTERNOON AND END UP ON THE WARM SIDE OF 32F.
SECONDLY...THE NAM AND EVEN THE UW WRFGFS SUGGEST THE 1000 TO 3000 FT
LAYER WILL WARM ABOVE FREEZING OVERNIGHT...ESPECIALLY AS THE HEAVIER
PRECIPITATION ARRIVES AND THE AIRMASS ALOFT BEGINS TO DESTABILIZE AND
MIX OUT SOME THE COLDEST AIR BANKED UP AGAINST THE EAST SIDE OF THE
CASCADES. IN ADDITION...NOT ALL THE RAIN WITH THIS LAST SYSTEM FROZE
UPON CONTACT. EVEN THOUGH QPF AMOUNTS APPEAR TO JUSTIFY A SECOND ICE
STORM WARNING...I THINK THE COMBINATION OF MARGINAL TEMPERATURES AND
SOME LIQUID RUNOFF...WILL RESULT IN ANY ADDITIONAL ICE ACCUMULATIONS
OVERNIGHT REMAINING UNDER A QUARTER OF AN INCH...AND THUS WITHIN
ADVISORY CRITERIA. NONETHELESS...GIVEN TREES AND POWER LINES ARE
CAKED IN A HALF INCH OF ICE IN THE UPPER HOOD RIVER VALLEY AND
EASTERN SKAMANIA COUNTY...THE SURFACE AREA ABLE TO ACCUMULATE ICE IS
SUBSTANTIALLY HIGHER THAN NORMAL SO ANY ADDITIONAL ICE ACCUMULATIONS
WILL CERTAINLY HAVE A HIGHER IMPACT THAN NORMAL...AND COULD BE THE
TIPPING POINT THAT RESULTS IN FALLING BRANCHES/TREES AND POWER
OUTAGES.
SHORTWAVE RIDGING STILL LOOKS ON TRACK FOR SATURDAY NIGHT AND SUNDAY
SO THE MENTION OF FOG FOR LATE SATURDAY NIGHT AND SUNDAY MORNING WAS
MAINTAINED. EXPECT ANY FOG AND LOW CLOUDS TO BE SLOW TO CLEAR
SUNDAY...AND DESPITE MODESTLY WARM TEMPERATURES ALOFT...MOST VALLEY
LOCATIONS WILL STAY RELATIVELY COOL...AS IS TYPICAL THIS TIME OF
YEAR.
MODELS SEEM TO AGREE PRECIPITATION WILL BE A LITTLE SLOWER TO ARRIVE
ON SUNDAY SO POPS WERE DELAYED SUNDAY AFTERNOON AND EVENING. ONCE
THIS STORM SYSTEM BRINGS A BRIEF BOUT OF WET WEATHER SUNDAY NIGHT...A
MUCH WETTER FRONT WILL PUSH INTO SOUTHWEST BRITISH COLUMBIA AND
WESTERN WASHINGTON MONDAY. THE BULK OF THE RAIN WILL STAY TO OUR
NORTHWEST...BUT FAR NORTHWEST OREGON AND SOUTHWEST WASHINGTON MAY SEE
STEADIER RAIN FOR MUCH OF THE DAY ON MONDAY. /NEUMAN
.LONG TERM...TUESDAY THROUGH FRIDAY...NOT MUCH CHANGE TO THE OVERALL
THINKING FOR THE EXTENDED FORECAST PERIOD. POPS WERE HELD ABOVE CLIMO
FOR MUCH OF THE FORECAST. A MORE COMPACT AND ENERGETIC STORM SYSTEM
LOOKS LIKE IT WILL IMPACT THE AREA ON TUESDAY...BUT WHETHER OR NOT
HIGH WINDS WILL SURFACE ON THE COAST REMAINS UNCERTAIN THIS FAR OUT.
A SECOND LOW PRESSURE SYSTEM DEVELOPING IN THE NORTHEAST PACIFIC WILL
SEND ANOTHER FRONT INTO THE REGION TOWARDS MIDWEEK...BUT AS THE UPPER
LEVEL JET PLOWS SOUTH OF THE REGION...THE FRONT WILL PIVOT MORE
LONGITUDINALLY AS IT PUSHES THROUGH THE REGION. THIS SHOULD ACT TO
HELP QPF TOTALS IN THE VALLEY...BUT PERHAPS CUT DOWN ON THE RAIN
TOTALS IN THE COAST RANGE AND CASCADES...AND HELP EASE ANY FLOOD
CONCERNS. ONCE THIS FRONT PUSHES THROUGH THE REGION...SNOW LEVELS
SHOULD LOWER AND ADDITIONAL ONSHORE FLOW SHOULD BRING PERIODS OF
SHOWERS TO THE AREA...LIKELY IN THE FORM OF SNOW ABOVE 4000 TO 5000
FT. HOWEVER...WITH THE MAIN JET AND UPPER LEVEL SUPPORT DIGGING WELL
TO OUR SOUTH...BIG MOUNTAIN SNOWS APPEAR UNLIKELY. /NEUMAN
&&
.AVIATION...MOST TAF SITES WILL SEE MVFR TO VFR CONDITIONS THROUGH
SAT. THE EXCEPTION BEING THE CENTRAL AND SOUTHERN WILLAMETTE
VALLEY WHICH WILL CONTINUE TO SEE IFR TO LIFR CIGS DUE TO LOW
LEVEL STRATUS. A SLIGHTLY STRONGER FRONT WILL MOVE ACROSS THE
REGION TONIGHT. THIS WILL LIKELY BRING BRIEF PERIODS OF IFR CIGS
AND VIS UNDER LIGHT TO MODERATE RAIN BANDS. KTTD WILL CONTINUE TO
SEE GUSTY EAST WINDS INTO LATE TONIGHT.
KPDX AND APPROACHES...VFR CONDITIONS EXPECTED TO PERSIST THROUGH
SAT. HOWEVER...A FRONT WILL SPREAD PRECIPITATION INLAND TONIGHT
AND COULD BRING BRIEF PERIODS OF LOWER CIGS AND VIS. /64
&&
.MARINE...A SLIGHTLY STRONGER FRONT WILL CONTINUE TO MOVE ACROSS
THE WATERS TONIGHT WITH SOLID SMALL CRAFT ADVISORY GUSTS TO 30
KT. THERE CONTINUES TO BE THE POTENTIAL FOR ISOLATED GALE FORCE
GUSTS OVER PORTIONS OF THE SOUTHERN WATERS DUE TO COASTAL JET
ENHANCEMENT WHICH COULD KEEP ADVISORY WINDS THROUGH SAT.
HOWEVER...CONFIDENCE REMAINS LOW THAT A COASTAL JET WILL DEVELOP
AND WE WILL NEED TO REEVALUATE IT WITH THE EVENING UPDATE.
EXPECT WINDS OVER THE NORTHERN WATERS TO DROP BELOW ADVISORY
CRITERIA BY LATE SAT MORNING. THE COMBINATION OF A FRESH SWELL AND
WIND WAVES MAY GENERATE LOCALLY STEEP SEAS. DO NOT HAVE ENOUGH
CONFIDENCE TO ISSUE A HAZARDOUS SEAS ADVISORY AT THE MOMENT AS
BUOY REPORTS HAVE SHOWN THAT THE WESTERLY SWELL CONTAINS MOST OF
THE ENERGY. /64
A SERIES OF PACIFIC STORMS WILL CROSS THE REGION BEGINNING
SATURDAY NIGHT AND THEN ABOUT EVERY 36 TO 48 HOURS THEREAFTER.
SOLID GALE GUSTS APPEAR LIKELY BY LATE SUNDAY...AND THERE IS SOME
POTENTIAL FOR HIGH END GALE GUSTS OR POSSIBLY LOW END STORM FORCE
GUSTS DURING THE EARLY PART OF NEXT WEEK. ADDITIONALLY...SEAS WILL
BUILD INTO THE MID TEENS LATER SUNDAY AND MAY APPROACH 20 FT
DURING THE EARLY PART OF NEXT WEEK. CULLEN
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...FREEZING RAIN ADVISORY UNTIL 10 AM PST SATURDAY FOR UPPER HOOD
RIVER VALLEY.
WA...FREEZING RAIN ADVISORY UNTIL 10 AM PST SATURDAY FOR SOUTH
WASHINGTON CASCADES.
PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL NOON PST SATURDAY FOR
COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR OUT 60 NM.
&&
$$
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.
Area Forecast Discussion
National Weather Service Spokane WA
240 PM PST FRI DEC 5 2014
.SYNOPSIS...
A series of storm systems will bring a wintry mix of precipitation
to the Pacific Northwest through a good portion of the weekend.
Each day valley temperatures will warm a bit meaning a gradual
transition from freezing rain and snow to just plain rain. A
break in storm systems occurs Sunday but ends quickly with more
winter storms passing through as early as Sunday night and
continuing on through at least the early part of the next
workweek.
&&
.DISCUSSION...
Tonight: Conditions will dry out across the eastern and southern
third of the forecast area while the Cascades...Wenatchee
Area...and areas of the northern mountain deal with a messy wintry
mix.
Precipitation for much of today has been uneventful to say
the least with most midlevel circulations falling apart once they
cross into Chelan County. Regional radar indicates a line of
showers continuing to fill in from Kittitas County southward to
the central Oregon Cascades which are tracking north toward the
Hwy 97 corridor. It is uncertain whether these showers will
survive the trip into Chelan/Douglas Counties but HRRR continues
to hint at some showers during the 23-02z time-frame. Most
locations remain below freezing with a few exceptions. With
wetbulb effects and sunset approaching, it is unlikely any
location will remain above freezing. The showers moving through
the next few hours will not be a major player for freezing
rain.
Freezing rain advisories were extended to capture steady
light to moderate precipitation moving in after midnight and
continuing into Saturday morning. This is a much different setup
compared the last 48 hours which have proved much drier than
expected. This system will feature southeast flow in the lower
levels, moderate isentropic ascent, and rich moisture. So as far
as I am concerned, the precipitation will be certain...now the
temperatures will be a bigger wild card. Temperatures are
typically slow to warm with SE flow in the lower levels however
as the air mass moistens...it has no where to go but warmer. When
this transition occurs will be the challenge of the night.
Needless to say, travel is likely to be slick near the Cascades
and Wenatchee Area. Some light precip is possible in the Okanogan
Valley and Northern Mountains but amounts should be low and
concerns are lower.
One other travel concern looks to be localized along Hwy 2 between
Airway Heights and Davenport which is dense fog. There may be a
few other areas out there, but this looks to be the worse case via
a tour of CAMS and motorists should plan on visibilities near 1/4
mile at times. Temperatures remain near 32F for most locations
north of I-90 so there is also the potential for black ice
redeveloping tonight. Temperatures will not fall much from current
readings (maybe 1-2 degrees) and may even rise or remain steady
for much of the night so we are not expecting a hard freeze in any
locations. /sb
Saturday through Monday...High pressure will be over the Pacific
Northwest through Sunday before getting pushed off to the east
Sunday night. A couple of vigorous but fast moving short wave
disturbances will move through the ridge...the first on
Saturday...the second on Monday. These two waves will result in
more wet weather across the region through the short term.
Temperatures will be on the increase with warm air advection and
should be above normal through Monday.
*Precipitation: Yes more wet weather with chances of mixed
precipitation. The wave moving through the region on Saturday
will tap into fairly deep Pacific moisture and combine with
moderate to strong isentropic up-glide and orographic lift for
light to moderate precipitation. Precipitation will be on the
increase across the western zones around 12z and push across the
forecast area through the day. A cold front will follow quickly
behind. The front should eject into Montana late Saturday
afternoon. Low level southeast-south flow Saturday morning will
eliminate any Cascade shadowing for the lowers east slopes and
the deep basin. The flow will shift around to the southwest-west
by late Saturday afternoon as the front moves through the area.
Drying from the west should begin by late morning, with
precipitation lingering across the Panhandle through the evening
hours. Saturday night and Sunday the area will be in a dry
period, although fog and low clouds will be probable. The next
weak wave will run through the ridge on Monday. This wave does
not have the deep moisture tap nor the lifting mechanism of the
previous wave but will still result in some very light
precipitation Monday afternoon.
*Precipitation type: The valleys up against the Cascades have had
difficulty mixing out the cold air damned up against the
mountains. All indications are that precipitation may be as
freezing rain overnight, but should turn over to snow before
sunrise Saturday...especially for the Methow valley. Along the
the Columbia river and some of the northern valleys freezing rain
may also be a possibility for a few hours early Saturday morning,
but with increasing southerly flow these valleys should switch
over to rain. Precipitation amounts will range from around a
tenth or more for the lower elevations and a quarter to a third
of an inch for the mountains for the Saturday system. Snow
accumulation of 3-4 inches will be possible for the mountains
with possibly 1-2 inches for the Methow valley. For the Monday
system precipitation should be as valley rain and mountain snow,
with very light accumulations. Tobin
Monday night through Friday: Confidence is high that the region
will see a pattern shift through next week. Medium range models
are in good agreement that the longwave ridge of high pressure
will shift east into the Rookies and over the Northern Plains.
This will place the region in a more mild and wet weather pattern.
A pair of very moist low pressure systems will impact the region.
There is still some uncertainty with the timing of these two
systems. There is better agreement with the first system as models
show the region firmly under the warm sector Monday night into
Tuesday, and then the cold front sweeping through around Tuesday
afternoon or night. Models diverge considerably more with the
second weather system. The ECMWF is faster and shows a stronger
warm frontal passage Tuesday night into Wednesday morning. The GFS
is much slower with precip redeveloping Wednesday afternoon/evening.
Snow levels will be increasing with each of these weather systems.
A pocket of cold air looks to remain along the lee side of the
northern Cascades into the Okanogan Highlands through at least
Monday night. This will keep snow levels lower to between 2,000
and 3,000 feet. There is a chance for some wet snow in the upper
reaches of the Methow Valley, but confidence is low. All other
valley locations are expected to see rainfall. Moderate to heavy
rainfall amounts will be possible with P-wats +2 standard
deviations of normal and up to between 0.75-1.00 inches.
Temperatures will warm to above normal through mid week. The upper
level trough in the Gulf of Alaska looks to dig in across the
region late next week. This will result in an end to the warming
trend with temperatures dipping back closer to normal by Friday.
/SVH
&&
.AVIATION...
18Z TAFS: A saturated low-level air mass is now established over
the Inland Northwest and most terminals will experience cig/vis
restrictions through 18z. For KGEG-KCOE...low stratus, fog, and
spotty freezing drizzle will be a concern through tomorrow
morning. The threat for drizzle will likely diminish this
afternoon and confidence is low regarding exact ceiling heights.
Further west, low clouds and periods of freezing rain will be the
concern for KMWH-KEAT. The next batch of precip will pass through
between 19-22z with a break until a wetter system arrives arnd
06z. Moses Lake will warm enough to support all rain but Wenatchee
will be on the fence for precip type...especially at the onset. To
the southeast, Pullman is the only site experiencing VFR
conditions and look to remain status quo until rain chances return
Sat morning. Not the case for Lewiston which is socked in low
clouds and will will be slow to recover until tonight when winds
increase ahead of the next storm system. /sb
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 31 37 32 37 31 39 / 10 90 20 0 10 30
Coeur d`Alene 31 35 33 36 31 39 / 10 90 40 0 10 30
Pullman 38 39 33 38 35 44 / 10 100 20 0 10 30
Lewiston 37 39 35 45 37 47 / 10 90 10 0 10 20
Colville 32 34 31 38 29 39 / 30 70 30 0 10 30
Sandpoint 29 34 32 37 29 36 / 10 90 50 10 0 30
Kellogg 34 35 33 38 30 38 / 10 100 50 0 0 30
Moses Lake 34 36 30 40 32 39 / 50 90 0 0 10 30
Wenatchee 31 35 30 39 32 39 / 80 80 0 0 20 30
Omak 30 34 28 33 29 36 / 60 80 0 10 10 30
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...Air Stagnation Advisory until Noon PST Tuesday for East Slopes
Northern Cascades-Northeast Mountains-Okanogan Highlands-
Okanogan Valley-Waterville Plateau-Wenatchee Area.
Freezing Rain Advisory until Noon PST Saturday for East Slopes
Northern Cascades-Wenatchee Area.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1141 PM CST THU DEC 4 2014
.UPDATE...
ISSUED AT 856 PM CST THU DEC 4 2014
THE MAIN FOCUS THIS EVENING HAS BEEN ON WHETHER OR NOT WE ARE
GOING TO GET ANY FREEZING DRIZZLE OVERNIGHT INTO TOMORROW
MORNING.
CURRENTLY...LOW LEVEL MOISTURE IS SURGING NORTHWARD INTO
SOUTH CENTRAL MINNESOTA BETWEEN A DEPARTING SURFACE RIDGE NOW
ALONG THE EAST COAST AND A DEVELOPING SURFACE LOW IN THE WESTERN
PLAINS. THE MODELS HAVE BEEN VERY CONSISTENT WITH SHOWING THIS RH
SURGE OVER THE PAST FEW DAYS OF MODEL RUNS AND THAT SCENARIO IS
NOW BEING PLAYED OUT WITH THE STRATUS EVIDENT IN OBS/SATELLITE.
WHILE THERE HAS BEEN HIGH CONFIDENCE IN THE CLOUD DECK COMING
IN...THERE HAS NOT BEEN MUCH CONFIDENCE IN HOW MUCH LIFT THERE
WILL BE IN THE LOW LEVELS/INVERSION LAYER TO PRODUCE SOME
DRIZZLE/MIST. THE PAST FEW RUNS OF THE RAP HAVE SHOWN LITTLE TO NO
ISENTROPIC LIFT ON THE 270-285K SURFACES (BELOW 850MB). IF THERE
IS ANY LIFT...IT APPEARS TO BE ABOVE THE INVERSION AT 850MB THANKS
TO A NORTH TO SOUTH ORIENTED 850MB WARM FRONT/TROUGH THAT IS ENTERING
WESTERN MINNESOTA PER 00Z RAOB DATA. THERE HAS BEEN SOME
DRIZZLE/RAIN REPORTED WELL TO THE SOUTH ALONG THE MAIN FRONT IN
SOUTHERN NEBRASKA/NORTHERN MISSOURI/CENTRAL ILLINOIS WHERE
CEILINGS HAVE BEEN DOWN BELOW 1KFT. BASED ON THE 04.21Z SREF
PROBABILITIES OF <1000FT CEILINGS HEIGHTS...THE HIGHEST CHANCE OF
THESE IFR CIGS RUNS FROM CENTRAL ILLINOIS TO THE NORTHWEST THROUGH
CENTRAL IOWA ON UP TOWARD THE TROUGH/SURFACE FRONT IN WESTERN
IOWA/SW MINNESOTA THROUGH THE EARLY MORNING. GOING INTO THE LATER
MORNING AND AFTERNOON FRIDAY...THE SURFACE WINDS LIGHTEN UP AND
THE SHALLOW INVERSION HOLDS TIGHT AND COULD HELP FORM SOME FOG AND
LOWER CEILINGS. HOWEVER...SURFACE TEMPERATURES AT THIS POINT
WOULD BE AT OR JUST ABOVE FREEZING...SO IMPACTS MAY BE MINIMAL.
LONG STORY SHORT...CONFIDENCE IS NOT HIGH ENOUGH RIGHT NOW IN
WHETHER THE FREEZING DRIZZLE WILL FORM TO ISSUE AN ADVISORY BUT
WILL HAVE TO MONITOR TRENDS OVERNIGHT.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 307 PM CST THU DEC 4 2014
AT 2 PM...A 1031 MB SURFACE HIGH WAS CENTERED OVER SAGINAW BAY
/PART OF LAKE HURON/. SOUTHERLY WINDS ON THE BACK SIDE OF THIS
HIGH HAVE CAUSED TEMPERATURES SOUTH OF INTERSTATE 94 TO CLIMB INTO
THE LOWER AND MID 30S. MEANWHILE NORTH OF THIS INTERSTATE...THE
TEMPERATURES ARE STILL IN THE 20S.
FOR TONIGHT AND FRIDAY MORNING...THE 04.12Z MODELS ARE IN GOOD
AGREEMENT THAT WEAK 925 TO 850 MB MOISTURE TRANSPORT WILL DEVELOP
ACROSS THE AREA. THIS IS IN ADVANCE OF A SHORT WAVE TROUGH WHICH
WILL BE MOVING EAST ACROSS NORTHERN MINNESOTA AND NORTHERN
WISCONSIN. THE NAM AND RAP SOUNDINGS SHOW THAT THE AIR MASS BELOW
800 MB WILL BECOME SATURATED AND THERE WILL BE SOME WEAK OMEGA IN
THIS LAYER. THIS WOULD RESULT IN PATCHY FREEZING DRIZZLE.
MEANWHILE THE GFS...SATURATES THE LAYER BETWEEN 950 AND 800 MB AND
KEEPS A DRY LAYER NEAR THE SURFACE. THIS WOULD RESULT IN JUST A
LIFR/IFR DECK OF CLOUDS. UNTIL THIS PAST HOUR WAS LEANING MORE TOWARD
THE GFS BECAUSE THERE WAS NO DRIZZLE OR LOW CLOUDS ACROSS NORTHERN
MISSOURI AND CENTRAL ILLINOIS. HOWEVER BOTH OF THESE ARE STARTING
TO SHOW UP IN THE OBSERVATIONS ACROSS THIS AREA...SO MAYBE THE NAM
AND RUC ARE HANDLING THIS BETTER THAN ORIGINALLY THOUGHT. DUE TO
THIS...KEPT A 15 PERCENT PRECIPITATION CHANCE FOR FREEZING
DRIZZLE IN THE FORECAST. LIKE THE PREVIOUS SHIFT...USED THE 925 TO
850 MB RELATIVE HUMIDITY TO TIME THE FREEZING DRIZZLE ONSET AND
ENDING.
ON FRIDAY AFTERNOON AND EVENING...A SHORT WAVE TROUGH IN THE
SOUTHERN STREAM WILL MOVE NORTHEAST THROUGH THE MID MISSISSIPPI
RIVER VALLEY INTO THE SOUTHERN GREAT LAKES. LIKE PREVIOUS
RUNS...IT LOOKS LIKE THE SYNOPTIC LIFT AND MOISTURE WILL REMAIN
SOUTHEAST OF THE FORECAST AREA. AS A RESULT...KEPT THE FORECAST
DRY.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 307 PM CST THU DEC 4 2014
FROM SUNDAY THROUGH MONDAY...THE MODELS CONTINUE TO SHOW THAT A
SHORT WAVE TROUGH WILL MOVE EAST THROUGH THE REGION. THIS WAVE
REMAINS AN OPEN WAVE SO THE MODELS ARE MORE PROGRESSIVE THAN THEY
WERE EARLIER. DUE TO THIS...IT LOOKS LIKE THE PRECIPITATION WILL
LIKELY ONLY OCCUR FOR AN 12 TO 18 HOUR PERIOD. SOME OF THE MODELS
SUGGEST THAT DRY AIR WILL MOVE IN ALOFT ON SUNDAY NIGHT. IF
THIS IS CORRECT...THERE WOULD BE A LOSS OF ICE FROM ALOFT...AND
THE PRECIPITATION TYPE WOULD CHANGE FROM SNOW TO EITHER A RAIN OR
FREEZING RAIN. SOME OF THE MODELS SUGGEST THAT THE TEMPERATURES
WILL REMAIN ABOVE FREEZING ACROSS MUCH OF THE AREA...SO MAY NOT
HAVE TOO MUCH OF A FREEZING RAIN THREAT. SINCE THIS IS STILL OVER
84 HOUR OUT...IT WAS THE CONSENSUS TO JUST KEEP THE FORECAST IN
THE FORM OF RAIN AND SNOW FOR NOW. WITH THE MIXED PRECIPITATION
AMOUNTS...DOES NOT LOOK LIKE THERE WILL BE TOO MUCH SNOW. GFS COBB
DATA CURRENTLY IS SHOWING A HALF INCH OR LESS OF SNOW.
ON WEDNESDAY...THE GFS SHOW THAT A SHORT WAVE TROUGH WILL PRODUCE
RAIN OR FREEZING RAIN AS IT MOVES THROUGH THE NORTHERN MINNESOTA
AND WISCONSIN. SOUNDINGS NORTH OF INTERSTATE 94 KEEP MUCH OF THEIR
SATURATION BELOW 900 MB AND BETWEEN 600 AND 700 MB...SO THINKING
THAT THE MODELS MAY BE OVER DOING THIS PRECIPITATION...SO OPTED TO
FOLLOW THE ECMWF AND KEEP THE FORECAST DRY FOR NOW.
ON THURSDAY...THE MODELS CONTINUE TO STRUGGLE ON HOW FAST WE WILL
WARM UP. THE GFS WARMS THE 850 MB TEMPERATURES INTO THE 10 TO 14C
RANGE. MEANWHILE THE ECMWF HAS THESE TEMPERATURES RANGING FROM 0
TO -4C. THE CFS VERSION 2 OVER THE PAST 5 DAYS ARE SUGGESTING
THAT THE HIGHS ON THIS DAY WILL RANGE FROM 35 TO 40 NORTH OF
INTERSTATE 94 AND FROM 40 TO 45 WITH A STANDARD DEVIATION LESS
THAN 1. MEANWHILE THE DETERMINISTIC ECMWF MOS HAS HIGHS AROUND
30...BUT THIS IS MUCH LOWER THAN ITS ENSEMBLE MEAN. WITH SUCH
DIFFERENCES STAYED NEAR THE MODEL BLEND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1141 PM CST THU DEC 4 2014
MVFR CEILINGS HAVE MOVED IN ACROSS THE TAF REGION AND WILL
CONTINUE TO DROP THROUGH FRIDAY MORNING AS MORE MOISTURE GETS SENT
NORTH. HOW FAST THE CEILINGS DROP TO IFR IS THE QUESTION WITH THE
RAP SUGGESTING THAT IT WILL BE FAIRLY SOON AFTER
MIDNIGHT...PARTICULARLY AT RST. FLIGHT CONDITIONS ARE EXPECTED TO
CONTINUE TO DROP THROUGH THE AFTERNOON AHEAD OF AN APPROACHING
COLD FRONT WITH WINDS DROPPING DOWN TO LIGHT AND VARIABLE. WHILE
THERE STILL IS A CHANCE FOR SOME FREEZING DRIZZLE...IT APPEARS AS
THOUGH THE FORCING MAY NOT BE ENOUGH TO PRODUCE ANYTHING OUTSIDE
OF SOME VERY LIGHT MIST IN THE AFTERNOON WHEN SOME FOG IS
POSSIBLE. THE COLD FRONT IS EXPECTED TO COME THROUGH IN THE EARLY
EVENING HOURS FRIDAY WHICH SHOULD MARK A RETURN OF DRIER AIR INTO
THE REGION AND SOME IMPROVEMENTS IN FLIGHT CONDITIONS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...HALBACH
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...HALBACH
AREA FORECAST DISCUSSION
NWS TAUNTON MA
359 AM EST SUN DEC 7 2014
.SYNOPSIS...
DRY BUT MUCH COLDER AND BLUSTERY WEATHER TODAY...LINGERING INTO
MONDAY. A LOW PRESSURE SYSTEM WILL MOVE INTO SOUTHERN NEW ENGLAND
TUESDAY AND LINGER THERE THROUGH THE MIDDLE OF THE WEEK. DRY
WEATHER RETURNS BY FRIDAY AND SATURDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
ANY EARLY MORNING PRECIP SHOULD BE CONFINED TO CAPE COD AND THE
ISLANDS AND MOVING QUICKLY OFFSHORE AS A COLD FRONT MOVES ACROSS
SOUTHERN NEW ENGLAND. AGAIN PRECIP COULD END AS A BRIEF PERIOD OF
SNOW AND/OR SLEET. LATEST RUNS OF THE HRRR LOOK TO HAVE A GOOD
TIMING FOR THE BACK EDGE...SO LEANED HEAVILY UPON THAT TIMING.
LOW PROBABILITY OF SOME SLICK SPOTS EARLY THIS MORNING ALONG AND
NORTHWEST OF I-95 IN MA AND RI AS TEMPERATURES FALL AT OR BELOW
FREEZING AND COMBINE WITH ANY RESIDUAL MOISTURE ON THE ROADS.
GOOD POST FRONTAL MIXING MAY DRY THINGS OUT FAIRLY QUICKLY.
BEHIND THIS FRONT...DRY CONDITIONS BUT WINDY AND MUCH COLDER WITH
NNE WINDS 15 TO 25 MPH GUSTING UP TO 35 MPH...EXCEPT UP TO 50 MPH
ACROSS CAPE COD AND ISLANDS. CLEARING WILL BE BRIEF...AS NNE FLOW
YIELDS LOTS OF OCEAN-EFFECT STRATOCUMULUS CLOUDS ACROSS EASTERN
MA. AT LEAST PARTLY SUNNY ELSEWHERE.
THE BIG QUESTION IS WILL THERE BE ENOUGH OF A TEMPERATURE
DIFFERENTIAL. WITH WATER TEMPERATURES IN THE UPPER 40S...ONLY
GETTING MAX DIFFERENTIALS ABOUT -5C TO -7C. THAT IS TYPICALLY NOT
ENOUGH TO GENERATE SUFFICIENT OCEAN-INDUCED CAPE. THERE IS ALSO
THE PROBLEM OF THE SIGNIFICANT SUBSIDENCE INVERSION BASED AROUND
950 MB WITH ABUNDANT DRY AIR ABOVE IT. THAT LEAVES ONLY A VERY
SHALLOW LAYER FOR ANY SHOWERS TO DEVELOP. LEFT A CHANCE OF
SNOW/SLEET SHOWERS IN THE FORECAST...BUT IT IS THE LOWEST
CONFIDENCE PORTION OF THIS FORECAST.
OTHERWISE...THERE SHOULD BE ENOUGH OF A PRESSURE GRADIENT BETWEEN
THE DEPARTING LOW PRESSURE AND A STRONG HIGH PRESSURE OVER
SOUTHEAST CANADA TO GENERATE STRONG NORTH TO NORTHEAST WINDS
ACROSS CAPE COD AND THE ISLANDS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/...
STRONG HIGH PRESSURE CONTINUES TO MOVE INTO THE MARITIMES AND
NORTHERN NEW ENGLAND TONIGHT. EXPECTING COLD CONDITIONS ACROSS ALL
OF SOUTHERN NEW ENGLAND....WITH GUSTY WINDS LINGERING ACROSS CAPE
COD AND THE ISLANDS. WINDS DIMINISH SOME MONDAY.
SREF AND HIGH RESOLUTION WRF CONTINUE TO HAVE HIGHER PRECIPITATION
CHANCES THAN JUST ABOUT ALL OTHER GUIDANCE. THIS COULD BE A
FUNCTION OF THE HIGHER RESOLUTION OF THE WRF MEMBERS. STILL SEEING
THE SAME ISSUES WITH OCEAN-EFFECT SHOWERS...THAT BEING THE STRONG
SUBSIDENCE INVERSION AND DEEP DRY AIR. MAINTAINED A CHANCE OF
SHOWERS ACROSS EASTERN MA AND PORTIONS OF RI FOR NOW...AND WILL
CONTINUE TO EVALUATE THIS POTENTIAL.
AFTER A VERY COLD START MONDAY MORNING...WILL SEE AFTERNOON HIGH
TEMPERATURES STAY BELOW NORMAL.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
HIGHLIGHTS...
* LOW PRESSURE WILL BRING UNSETTLED MOSTLY RAINY WEATHER TO THE AREA
THROUGHOUT THE MIDDLE OF THE WEEK
* DRY WEATHER RETURNS BY FRIDAY AND SATURDAY
THE MODELS...WHILE CONTINUING TO STRUGGLE WITH A LOW PRESSURE SYSTEM
APPROACHING SOUTHERN NEW ENGLAND...ARE COMING INTO BETTER AGREEMENT.
THE ECMWF HAS BEEN MORE CONSISTENT WITH A DEEP...SOMETIMES
NEGATIVELY TILTED MID LEVEL TROUGH PULLING A COASTAL LOW IN TOWARDS
SOUTHERN NEW ENGLAND. THE LOW THEN ROTATES AROUND THE AREA FOR
SEVERAL DAYS. THE 06/00Z GFS IS FINALLY IN BETTER AGREEMENT WITH
THE ECMWF...THOUGH IT IS A BIT MORE PROGRESSIVE. FINALLY...THE GEFS
MEMBERS SHOW A LOW PRESSURE SYSTEM AFFECTING SOUTHERN NEW ENGLAND
BUT ALL WITH SOMEWHAT DIFFERENT TRACKS AND SPEEDS. THEREFORE GIVEN
ITS CONSISTENCY...FEEL THE ECMWF SOLUTION IS THE WAY TO GO.
TUESDAY THROUGH THURSDAY...AS STATED ABOVE...WE ARE SEEING BETTER
AGREEMENT WITH THIS SYSTEM. THERE IS STILL SOME UNCERTAINTY AS TO
HOW PROGRESSIVE THE STORM WILL BE. AS THE LOW PRESSURE SYSTEM
INTENSIFIES...AN ANOMALOUSLY STRONG /3 TO 4 STD/ EASTERLY LOW LEVEL
JET DEVELOPS...RESULTING IN PLENTY OF MOISTURE AND STRONG FORCING.
WHILE THE MAIN CONCERN IS TUESDAY...THERE IS POTENTIAL FOR THIS
STORM TO LINGER THROUGH THURSDAY SO WILL KEEP ALL TOGETHER FOR NOW.
SNOW...WHILE HIGH PRESSURE IS IN THE MARITIMES /NOT AN IDEAL
LOCATION FOR COLDER AIR FILTERING INTO SOUTHERN NEW ENGLAND/...
THERMAL PROFILES ARE ISOTHERMAL ACROSS THE NORTHWESTERN ZONES. THEY
ARE RIGHT AT ZERO DEGREES SO A SMALL SHIFT IN EITHER DIRECTION IS
GOING TO BE THE DIFFERENCE BETWEEN SNOW AND RAIN. STRONG FORCING
MEANS EITHER SNOW OR RAIN COULD BE QUITE HEAVY WITH 2 INCH PER HOUR
SNOWFALL RATES POSSIBLE. HOWEVER...THIS IS STILL A LOW CONFIDENCE
SITUATION.
HEAVY RAIN...TEMPERATURE PROFILES ARE SUCH THAT WE ARE EXPECTING
MOSTLY RAIN ACROSS THE AREA. WITH THE LOW MOVING AS SLOWLY AS IT IS
ON THE ECMWF SOLUTION...WE ARE LOOKING AT A PROLONGED PERIOD OF RAIN
WITH WIDESPREAD RAINFALL AMOUNTS OF TWO TO THREE INCHES. WHILE THIS
WILL NOT BE ENOUGH FOR ANY RIVER FLOODING...THIS WILL LIKELY RESULT
IN SOME URBAN/POOR DRAINAGE FLOODING. BECAUSE OF THE FORCING
ASSOCIATED WITH THE 3-4 STANDARD DEVIATION LOW LEVEL JET...MUCH OF
THIS RAIN COULD FALL OVER A SHORT PERIOD OF TIME.
WIND...WITH THIS ANOMALOUSLY STRONG LOW LEVEL JET...EXPECTING
EASTERLY WINDS AT THE SURFACE GUSTING TO AT LEAST 45 MPH...IF NOT
HIGHER ALONG THE EAST COAST...CAPE...AND ISLANDS. THERE IS ALSO A
LOW PROBABILITY OF HIGH WIND CRITERIA /60 MPH GUSTS OR HIGHER/.
THERE IS POTENTIAL FOR COASTAL FLOODING AS WELL. SEE TIDES/COASTAL
FLOODING SECTION BELOW FOR MORE INFORMATION.
FRIDAY AND SATURDAY...AT THIS POINT BOTH MODELS HAVE A RETURN TO
DRIER WEATHER WITH HIGH PRESSURE SLOWLY BUILDING INTO THE REGION.
&&
.AVIATION /09Z SUNDAY THROUGH THURSDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
TODAY...VFR EXCEPT LINGERING IFR/MVFR OVER CAPE COD AND ISLANDS
EARLY. NE WINDS GUSTING UP TO 45 KT OVER CAPE COD AND ISLANDS.
IFR/MVFR RETURN TO EASTERN MA IN THE AFTERNOON AS SNOW SHOWERS
OVER EASTERN MA WATERS COME ONSHORE.
TONIGHT...VFR EXCEPT IFR/MVFR ACROSS EASTERN MA IN SCATTERED SNOW
SHOWERS ALONG WITH NE WINDS G35 KT...HIGHEST CAPE COD AND ISLANDS.
SOME MINOR ACCUMULATION POSSIBLE ACROSS PORTIONS OF EASTERN MA.
MONDAY...MODERATE CONFIDENCE. MVFR CONDITIONS SPREAD INLAND FROM
THE COAST AS THE DAY WEARS ON WITH ONSHORE FLOW. EVEN SOME IFR
CIGS POSSIBLE ALONG THE COAST FOR A TIME IN A FEW RAIN/SNOW
SHOWERS.
KBOS TERMINAL...HIGH CONFIDENCE IN TAF.
KBDL TERMINAL...HIGH CONFIDENCE IN TAF.
OUTLOOK...MONDAY NIGHT THROUGH THURSDAY...
MONDAY NIGHT...MODERATE CONFIDENCE. MVFR CONDITIONS LIKELY WITH IFR
CIGS POSSIBLE ALONG THE COAST FOR A TIME IN A FEW RAIN/SNOW SHOWERS.
TUESDAY...MODERATE CONFIDENCE. MVFR-IFR CONDITIONS EXPECTED IN
MAINLY RAIN...WITH PERHAPS A PERIOD OF HEAVY WET SNOW ACROSS
NORTHWEST MA/NORTH CENTRAL MA. NORTHEAST WIND GUSTS OF 40 TO 45
KNOTS POSSIBLE ALONG THE COAST. LOW RISK FOR A FEW GUSTS UP TO 50
KNOTS ALONG THE COAST.
WEDNESDAY AND THURSDAY...LOW TO MODERATE CONFIDENCE. PERIODS OF
MAINLY MVFR TO VFR CONDITIONS IN SOME RAIN/SNOW SHOWERS. BRIEF
TIMES OF IFR CONDITIONS ARE ALSO POSSIBLE...BUT VERY LOW CONFIDENCE
IN TIMING.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH MONDAY/...HIGH CONFIDENCE.
*** NORTHEAST GALES INTO SUNDAY NIGHT ***
TODAY...RAIN OVER CAPE COD AND NANTUCKET WATERS AT SUNRISE
QUICKLY MOVES OFFSHORE. GUSTY NNE WINDS CONTINUE WITH GUSTS UP TO
45 KT POSSIBLE...STRONGEST WINDS CAPE COD AND NANTUCKET WATERS.
ROUGH SEAS EASTERN MA WATERS. NNE WINDS WILL LIKELY GENERATE OCEAN
EFFECT SNOW SHOWERS LATER IN THE DAY.
TONIGHT...NNE GALES THRU THE EVENING AND THEN EASING SLOWLY
TOWARD MONDAY MORNING. OCEAN-EFFECT SNOW SHOWERS WILL REDUCE
VSBY. ROUGH SEAS EASTERN MA WATERS.
MONDAY...HIGH CONFIDENCE. STRONG HIGH PRESSURE OVER THE CANADIAN
MARITIMES WILL BE ENOUGH TO GENERATE NORTHEAST WIND GUSTS OF 20 TO
30 KNOTS. STRONGEST WINDS ACROSS THE SOUTHERN WATERS. SMALL CRAFT
ADVISORY HEADLINES WILL BE NEEDED.
OUTLOOK...MONDAY NIGHT THROUGH THURSDAY...
***HIGH IMPACT MARINE EVENT EXPECTED WITH 15 TO 20 FOOT SEAS AND AT
LEAST 40 TO 45 KNOT WIND GUSTS ON TUESDAY***
MONDAY NIGHT ...HIGH CONFIDENCE. STRONG HIGH PRESSURE OVER THE
CANADIAN MARITIMES WILL BE ENOUGH TO GENERATE EASTERLY WIND GUSTS OF
20 TO 30 KNOTS. STRONGEST WINDS ACROSS THE SOUTHERN WATERS.
TUESDAY...MODERATE TO HIGH CONFIDENCE. INTENSIFYING LOW PRESSURE
APPROACHES SOUTHERN NEW ENGLAND WITH STRONG HIGH PRESSURE ACROSS THE
CANADIAN MARITIMES. HIGH CONFIDENCE IN NORTHEAST WIND GUSTS OF 40
TO 45 KNOTS AND GALE WARNINGS ARE A SLAM DUNK. THERE IS A LEAST A
LOW PROBABILITY FOR A PERIOD OF STORM FORCE WINDS WITH THE POTENTIAL
FOR WIND GUSTS TO 50 KNOTS. SEAS ARE EXPECTED TO BUILD TO BETWEEN
15 TO 20 FEET ACROSS THE EASTERN OPEN WATERS. HAVE ISSUED A
COMBINATION OF GALE AND STORM WATCHES FOR THE COASTAL WATERS.
WEDNESDAY AND THURSDAY...LOW CONFIDENCE. UNCERTAINTY ON LOCATION OF
THE LOW PRESSURE SYSTEM...SO WIND DIRECTION AND SEAS ARE UNCERTAIN.
REGARDLESS...AT LEAST SCA WIND GUSTS AND SEAS ARE EXPECTED.
&&
.TIDES/COASTAL FLOODING...
ASTRONOMICAL TIDES ARE FAIRLY HIGH DURING THE LATE MORNING.
HOWEVER...IT WILL TAKE SOME TIME FOR SURGE TO BE GENERATED AS
WINDS TURN NORTH TO NORTHEAST. AS A RESULT...THERE COULD BE MINOR
SPLASHOVER AT THE MORE VULNERABLE COASTAL LOCATIONS. THE
ASTRONOMICAL TIDE TONIGHT IS LOWER...SO NOT AS MUCH OF A CONCERN.
THE BIGGEST CONCERN IS THE ASTRONOMICAL HIGH TIDE ALONG THE EASTERN
MA COAST DURING THE MIDDAY TUE HIGH TIDE. TIMING OF STRONGEST
WINDS/WAVE HEIGHTS REMAINS SOMEWHAT UNCERTAIN. GFS MIGHT BE A BIT
FAST COMPARED TO THE ECMWF/GEFS ENSEMBLES. THE GFS WOULD HAVE
WINDS/SEAS RAMPED UP BY TUE AFTERNOON...WHILE ECMWF SHOWS IT
OCCURRING 3 TO 6 HOURS LATER. IF THE GFS VERIFIES...WE WOULD BE
LOOKING AT THE POTENTIAL FOR A MODERATE COASTAL FLOOD EVENT ON
EASTERN MA COAST. LEANING A BIT MORE TOWARDS THE SLOWER
ECMWF...WHICH WOULD STILL BRING THE RISK FOR A MINOR COASTAL FLOOD
EVENT WITH A 2+ FOOT SURGE POSSIBLE. EITHER WAY...DEFINITELY THIS
RISK FOR AT LEAST SOME MINOR COASTAL FLOODING/BEACH EROSION SO
SOMETHING TO WATCH.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...WIND ADVISORY UNTIL 1 AM EST MONDAY FOR MAZ022>024.
RI...WIND ADVISORY UNTIL 1 AM EST MONDAY FOR RIZ008.
MARINE...GALE WARNING UNTIL 10 PM EST THIS EVENING FOR ANZ231>234-236.
SMALL CRAFT ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR ANZ230.
GALE WARNING UNTIL 10 PM EST THIS EVENING FOR ANZ235-237.
GALE WARNING UNTIL 1 AM EST MONDAY FOR ANZ250-251.
GALE WARNING UNTIL 7 AM EST MONDAY FOR ANZ254-255.
GALE WARNING UNTIL 6 AM EST MONDAY FOR ANZ256.
&&
$$
SYNOPSIS...BELK/RLG
NEAR TERM...BELK
SHORT TERM...BELK
LONG TERM...RLG
AVIATION...BELK/RLG
MARINE...BELK/RLG
TIDES/COASTAL FLOODING...BELK/RLG
AREA FORECAST DISCUSSION
NWS TAUNTON MA
218 AM EST SUN DEC 7 2014
.SYNOPSIS...
A LOW PRESSURE WILL TRACK SOUTH OF NEW ENGLAND TONIGHT...RESULTING
IN PERIODS OF RAIN...HEAVY AT TIMES ACROSS CT/RI AND SOUTH OF THE
PIKE IN MASSACHUSETTS. DRY BUT MUCH COLDER AND BLUSTERY WEATHER
FOLLOWS SUNDAY....AND LINGERS INTO MONDAY. A STRONG COASTAL STORM
WILL LIKELY IMPACT THE REGION WITH PERIODS OF HEAVY RAIN AND
STRONG WINDS ALONG THE COAST TUESDAY...AND POSSIBLY A PERIOD OF
ACCUMULATING WET SNOW ACROSS NORTHWEST AND NORTH CENTRAL
MASSACHUSETTS. UNSETTLED WEATHER MAY LINGER WEDNESDAY INTO
THURSDAY...BUT THIS WILL LIKELY BE MIXED WITH TIMES OF DRY
WEATHER. DRY AND SEASONABLE WEATHER IS EXPECTED FOR THE START OF
NEXT WEEKEND.
&&
.NEAR TERM /THROUGH TODAY/...
ANY EARLY MORNING PRECIP SHOULD BE CONFINED TO CAPE COD AND THE
ISLANDS AND MOVING QUICKLY OFFSHORE AS A COLD FRONT MOVES ACROSS
SOUTHERN NEW ENGLAND. AGAIN PRECIP COULD END AS A BRIEF PERIOD OF
SNOW AND/OR SLEET. LATEST RUNS OF THE HRRR LOOK TO HAVE A GOOD
TIMING FOR THE BACK EDGE...SO LEANED HEAVILY UPON THAT TIMING.
LOW PROBABILITY OF SOME SLICK SPOTS EARLY THIS MORNING ALONG AND
NORTHWEST OF I-95 IN MA AND RI AS TEMPERATURES FALL AT OR BELOW
FREEZING AND COMBINE WITH ANY RESIDUAL MOISTURE ON THE ROADS.
GOOD POST FRONTAL MIXING MAY DRY THINGS OUT FAIRLY QUICKLY.
BEHIND THIS FRONT...DRY CONDITIONS BUT WINDY AND MUCH COLDER WITH
NNE WINDS 15 TO 25 MPH GUSTING UP TO 35 MPH...EXCEPT UP TO 50 MPH
ACROSS CAPE COD AND ISLANDS. CLEARING WILL BE BRIEF...AS NNE FLOW
YIELDS LOTS OF OCEAN-EFFECT STRATOCUMULUS CLOUDS ACROSS EASTERN
MA. AT LEAST PARTLY SUNNY ELSEWHERE.
THE BIG QUESTION IS WILL THERE BE ENOUGH OF A TEMPERATURE
DIFFERENTIAL. WITH WATER TEMPERATURES IN THE UPPER 40S...ONLY
GETTING MAX DIFFERENTIALS ABOUT -5C TO -7C. THAT IS TYPICALLY NOT
ENOUGH TO GENERATE SUFFICIENT OCEAN-INDUCED CAPE. THERE IS ALSO
THE PROBLEM OF THE SIGNIFICANT SUBSIDENCE INVERSION BASED AROUND
950 MB WITH ABUNDANT DRY AIR ABOVE IT. THAT LEAVES ONLY A VERY
SHALLOW LAYER FOR ANY SHOWERS TO DEVELOP. LEFT A CHANCE OF
SNOW/SLEET SHOWERS IN THE FORECAST...BUT IT IS THE LOWEST
CONFIDENCE PORTION OF THIS FORECAST.
OTHERWISE...THERE SHOULD BE ENOUGH OF A PRESSURE GRADIENT BETWEEN
THE DEPARTING LOW PRESSURE AND A STRONG HIGH PRESSURE OVER
SOUTHEAST CANADA TO GENERATE STRONG NORTH TO NORTHEAST WINDS
ACROSS CAPE COD AND THE ISLANDS.
&&
.SHORT TERM /TONIGHT THROUGH 6 PM MONDAY/...
STRONG HIGH PRESSURE CONTINUES TO MOVE INTO THE MARITIMES AND
NORTHERN NEW ENGLAND TONIGHT. EXPECTING COLD CONDITIONS ACROSS ALL
OF SOUTHERN NEW ENGLAND....WITH GUSTY WINDS LINGERING ACROSS CAPE
COD AND THE ISLANDS. WINDS DIMINISH SOME MONDAY.
SREF AND HIGH RESOLUTION WRF CONTINUE TO HAVE HIGHER PRECIPITATION
CHANCES THAN JUST ABOUT ALL OTHER GUIDANCE. THIS COULD BE A
FUNCTION OF THE HIGHER RESOLUTION OF THE WRF MEMBERS. STILL SEEING
THE SAME ISSUES WITH OCEAN-EFFECT SHOWERS...THAT BEING THE STRONG
SUBSIDENCE INVERSION AND DEEP DRY AIR. MAINTAINED A CHANCE OF
SHOWERS ACROSS EASTERN MA AND PORTIONS OF RI FOR NOW...AND WILL
CONTINUE TO EVALUATE THIS POTENTIAL.
AFTER A VERY COLD START MONDAY MORNING...WILL SEE AFTERNOON HIGH
TEMPERATURES STAY BELOW NORMAL.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
HIGHLIGHTS...
* STRONG NOREASTER LIKELY TUE W/HEAVY RAIN + STRONG COASTAL WINDS
* ACCUM SNOW POSS TUE INTERIOR NORTHERN MA BEFORE CHANGE TO RAIN
* UNSETTLED WEATHER MAY LINGER WED INTO THU - BUT NOT THE ENTIRE TIME
* MAINLY DRY AND SEASONABLY BY NEXT FRI AND SAT
DETAILS...
MONDAY NIGHT...
THE COLD ONSHORE FLOW SHOULD RESULT IN LIGHT OCEAN EFFECT SNOW
SHOWERS ACROSS THE EASTERN MA COAST MON NIGHT. SHALLOW INVERSION
SHOULD KEEP ANY SNOW AMOUNTS PROBABLY UNDER 1 INCH...BUT CAN/T
RULE OUT SOME SLICK SPOTS ALONG THE COAST. PTYPE MAY GRADUALLY
CHANGE TO LIGHT RAIN SHOWERS ALONG THE SOUTHEAST NEW ENGLAND COAST
AS MILDER AIR BEGINS TO WORK IN OFF THE OCEAN.
TUESDAY...
THE MAIN EVENT APPEARS TO BE ON TUESDAY INTO TUESDAY EVENING. VERY
STRONG NORTHERN STREAM ENERGY WILL DIVE SOUTHEASTWARD ACROSS THE
GREAT LAKES AND CLOSE OFF OVER THE NORTHEAST...BECOMING NEGATIVELY
TILTED. THIS WILL ALLOW A DISTANT LOW PRESSURE SYSTEM OFF THE MID
ATLANTIC COAST TO GET PULLED BACK TO THE NORTHWEST AND APPROACH
SOUTHERN NEW ENGLAND. AS THIS LOW PRESSURE SYSTEM INTENSIFIES A
STRONG EASTERLY LOW LEVEL JET WILL DEVELOP...RESULTING IN PLENTY OF
MOISTURE/VERY STRONG FORCING. GFS APPEARS IT MAY BE BIT FAST
COMPARED TO SOME OF ITS ENSEMBLES/ECMWF MODEL...SO THINK BRUNT OF
STORM WILL HOLD OFF UNTIL TUE INTO TUE EVENING.
1) ACCUMULATING SNOW POTENTIAL FOR NORTH CENTRAL/NORTHWEST MA:
THE PROBLEM FOR THIS EVENT IS THAT THERE IS AN INITIAL WEAK LOW
PRESSURE SYSTEM THAT MOVES WELL TO OUR NORTHWEST ACROSS THE GREAT
LAKES. THIS ALLOW SOME WARMING ALOFT OUT AHEAD OF THE MAIN EVENT.
THE LARGE HIGH PRESSURE SYSTEM SHIFTS EAST TOWARDS THE CANADIAN
MARITIMES...NOT AN IDEAL POSITIONING FOR MUCH OF THE REGION TO KEEP
COLD AIR IN PLACE.
THEREFORE...MOST OF THE PRECIPITATION WILL BE IN THE FORM OF RAIN ON
TUE. HOWEVER...DEPENDING ON THE EXACT TRACK WILL HAVE TO BE CAREFUL
ACROSS NORTHWEST/NORTH CENTRAL MA. MID LEVEL CENTERS ARE CLOSING OFF
AT THIS TIME. THERMAL PROFILES ARE CLOSE TO ISOTHERMAL AND VERY
STRONG FORCING WILL MAKE IT A CLOSE CALL BETWEEN A HEAVY THUMP OF
SNOW PERHAPS JUST A COLD RAIN. GIVEN THE EVENT IS STILL 72 HOURS
OUT IN THE MODEL WORLD...A SLIGHT CHANGE IN POSITIONING CAN MAKE ALL
THE DIFFERENCE. CERTAINLY SOMETHING THAT WILL NEED TO BE WATCHED
BECAUSE THE POTENTIAL EXISTS FOR MAINLY RAIN OR 2 INCH PER HOUR
SNOWFALL RATES. SO AS YOU CAN SEE THE STAKES ARE QUITE HIGH FOR A
SMALL PORTION OF OUR REGION.
2) HEAVY RAIN AND URBAN FLOODING:
VERY STRONG FORCING WITH STRONG EASTERLY LOW LEVEL JET WILL RESULT
IN MUCH OF THE AREA RECEIVING HEAVY RAINFALL ON TUESDAY. EASTERLY
LOW LEVEL JET IS PROGGED TO BE 3 TO 4 STANDARD DEVIATIONS ABOVE
NORMAL...RESULTING IN VERY STRONG FORCING. MOST MODELS ARE IN
AGREEMENT WITH 1.50 TO 3 INCHES OF RAIN ACROSS MUCH OF THE REGION.
WHILE THIS SHOULD NOT CAUSE RIVER FLOODING...SOME URBAN/POOR
DRAINAGE STREET FLOODING IS LIKELY. MUCH OF THIS HEAVY RAIN MAY
FALL OVER A VERY SHORT TIME...WHICH WOULD INCREASE THE RISK FOR SOME
STREET FLOODING.
3) STRONG WINDS:
EASTERLY LOW LEVEL JET OF 50 TO 60 KNOTS WILL LIKELY RESULT IN AT
LEAST WIND ADVISORY CRITERIA BEING MET ON TUESDAY ALONG THE EASTERN
MA COAST/CAPE/ISLANDS. LOW PROBABILITY FOR HIGH WIND WATCH/WARNING
CRITERIA BEING MET AS WELL...BUT EITHER WAY SOME WIND HEADLINES WILL
LIKELY BE NEEDED. NORTHEAST WIND GUSTS OF 40 TO 55 MPH ARE A GOOD
BET ALONG THE COAST.
4) COASTAL FLOODING:
THE BIGGEST CONCERN IS THE ASTRONOMICAL HIGH TIDE ALONG THE EASTERN
MA COAST DURING THE MIDDAY TUE HIGH TIDE. TIMING OF STRONGEST
WINDS/WAVE HEIGHTS REMAINS SOMEWHAT UNCERTAIN. GFS MIGHT BE A BIT
FAST COMPARED TO THE ECMWF/GEFS ENSEMBLES. THE GFS WOULD HAVE
WINDS/SEAS RAMPED UP BY TUE AFTERNOON...WHILE ECMWF SHOWS IT
OCCURRING 3 TO 6 HOURS LATER. IF THE GFS VERIFIES...WE WOULD BE
LOOKING AT THE POTENTIAL FOR A MODERATE COASTAL FLOOD EVENT ON
EASTERN MA COAST. LEANING A BIT MORE TOWARDS THE SLOWER
ECMWF...WHICH WOULD STILL BRING THE RISK FOR A MINOR COASTAL FLOOD
EVENT WITH A 2+ FOOT SURGE POSSIBLE. EITHER WAY...DEFINITELY THIS
RISK FOR AT LEAST SOME MINOR COASTAL FLOODING/BEACH EROSION SO
SOMETHING TO WATCH.
WEDNESDAY AND THURSDAY...
LOW CONFIDENCE FORECAST OVER THIS TIME. VERTICALLY STACKED LOW
PRESSURE WILL MEANDER AROUND NEW ENGLAND...CUTOFF FROM THE MAIN
UPPER LEVEL FLOW. THE GFS/GGEM SHOW THE CLOSED UPPER LEVEL LOW
GENERALLY TO OUR NORTH OVER THIS TIME. IF THESE SOLUTIONS
VERIFY...MUCH OF WED AND THU WOULD BE DRY OTHER THAN A FEW RAIN/SNOW
SHOWERS AT TIMES. HOWEVER...THE ECMWF HAS THE 500 MB LOW TO OUR
SOUTH FOR A TIME LATE WED INTO EARLY THU. IF THIS VERIFIES COULD
PUT US IN THE TROWAL AND A PERIOD OF EVEN ACCUMULATING SNOW
ACROSS PORTIONS OF SOUTHERN NEW ENGLAND. AGAIN...VERY LOW
CONFIDENCE BUT SOMETHING WILL NEED TO WATCH.
FRIDAY AND SATURDAY...
UPPER LEVEL LOW FINALLY BEGINS TO LOSE ITS GRIP ON THE REGION
PUSHING OFF TO THE NORTHEAST. THIS ALLOWS MAINLY DRY WEATHER WITH
SEASONABLE TEMPS FRI INTO SAT.
&&
.AVIATION /07Z SUNDAY THROUGH THURSDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
TODAY...VFR EXCEPT LINGERING IFR/MVFR OVER CAPE COD AND ISLANDS
EARLY. NE WINDS GUSTING UP TO 45 KT OVER CAPE COD AND ISLANDS.
IFR/MVFR RETURN TO EASTERN MA IN THE AFTERNOON AS SNOW SHOWERS
OVER EASTERN MA WATERS COME ONSHORE.
TONIGHT...VFR EXCEPT IFR/MVFR ACROSS EASTERN MA IN SCATTERED SNOW
SHOWERS ALONG WITH NE WINDS G35 KT...HIGHEST CAPE COD AND ISLANDS.
SOME MINOR ACCUMULATION POSSIBLE ACROSS PORTIONS OF EASTERN MA.
MONDAY...MODERATE CONFIDENCE. MVFR CONDITIONS SPREAD INLAND FROM
THE COAST AS THE DAY WEARS ON WITH ONSHORE FLOW. EVEN SOME IFR
CIGS POSSIBLE ALONG THE COAST FOR A TIME IN A FEW RAIN/SNOW
SHOWERS.
KBOS TERMINAL...HIGH CONFIDENCE IN TAF.
KBDL TERMINAL...HIGH CONFIDENCE IN TAF.
OUTLOOK...MONDAY NIGHT THROUGH THURSDAY...
TUESDAY...MODERATE CONFIDENCE. MVFR-IFR CONDITIONS EXPECTED IN
MAINLY RAIN...WITH PERHAPS A PERIOD OF HEAVY WET SNOW ACROSS
NORTHWEST MA/NORTH CENTRAL MA. NORTHEAST WIND GUSTS OF 40 TO 45
KNOTS POSSIBLE ALONG THE COAST. LOW RISK FOR A FEW GUSTS UP TO 50
KNOTS ALONG THE COAST.
WEDNESDAY AND THURSDAY...LOW TO MODERATE CONFIDENCE. PERIODS OF
MAINLY MVFR TO VFR CONDITIONS IN SOME RAIN/SNOW SHOWERS. BRIEF
TIMES OF IFR CONDITIONS ARE ALSO POSSIBLE...BUT VERY LOW CONFIDENCE
IN TIMING.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH MONDAY/...HIGH CONFIDENCE.
*** NORTHEAST GALES INTO SUNDAY NIGHT ***
TODAY...RAIN OVER CAPE COD AND NANTUCKET WATERS AT SUNRISE
QUICKLY MOVES OFFSHORE. GUSTY NNE WINDS CONTINUE WITH GUSTS UP TO
45 KT POSSIBLE...STRONGEST WINDS CAPE COD AND NANTUCKET WATERS.
ROUGH SEAS EASTERN MA WATERS. NNE WINDS WILL LIKELY GENERATE OCEAN
EFFECT SNOW SHOWERS LATER IN THE DAY.
TONIGHT...NNE GALES THRU THE EVENING AND THEN EASING SLOWLY
TOWARD MONDAY MORNING. OCEAN-EFFECT SNOW SHOWERS WILL REDUCE
VSBY. ROUGH SEAS EASTERN MA WATERS.
MONDAY...HIGH CONFIDENCE. STRONG HIGH PRESSURE OVER THE CANADIAN
MARITIMES WILL BE ENOUGH TO GENERATE NORTHEAST WIND GUSTS OF 20 TO
30 KNOTS. STRONGEST WINDS ACROSS THE SOUTHERN WATERS. SMALL CRAFT
ADVISORY HEADLINES WILL BE NEEDED.
OUTLOOK...MONDAY NIGHT THROUGH THURSDAY...
***HIGH IMPACT MARINE EVENT EXPECTED WITH 15 TO 20 FOOT SEAS AND AT
LEAST 45 KNOT WIND GUSTS ON TUESDAY***
TUESDAY...MODERATE TO HIGH CONFIDENCE. INTENSIFYING LOW PRESSURE
APPROACHES SOUTHERN NEW ENGLAND WITH STRONG HIGH PRESSURE ACROSS
THE CANADIAN MARITIMES. HIGH CONFIDENCE IN NORTHEAST WIND GUSTS OF
40 TO 45 KNOTS AND GALE WARNINGS ARE A SLAM DUNK. THERE IS A LEAST
A LOW PROBABILITY FOR A PERIOD OF STORM FORCE WINDS WITH THE
POTENTIAL FOR WIND GUSTS TO 50 KNOTS. SEAS ARE EXPECTED TO BUILD
TO BETWEEN 15 TO 20 FEET ACROSS THE EASTERN OPEN WATERS. WILL
ISSUE A MARINE WEATHER STATEMENT TO HIGHLIGHT THESE CONCERNS.
WEDNESDAY AND THURSDAY...LOW CONFIDENCE. UNCERTAINTY ON LOCATION OF
THE LOW PRESSURE SYSTEM...SO WIND DIRECTION AND SEAS ARE UNCERTAIN.
REGARDLESS...AT LEAST SCA WIND GUSTS AND SEAS ARE EXPECTED.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...WIND ADVISORY UNTIL 1 AM EST MONDAY FOR MAZ022>024.
RI...WIND ADVISORY UNTIL 1 AM EST MONDAY FOR RIZ008.
MARINE...GALE WARNING UNTIL 10 PM EST THIS EVENING FOR ANZ231>234-236.
SMALL CRAFT ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR ANZ230.
GALE WARNING UNTIL 10 PM EST THIS EVENING FOR ANZ235-237.
GALE WARNING UNTIL 1 AM EST MONDAY FOR ANZ250-251.
GALE WARNING UNTIL 7 AM EST MONDAY FOR ANZ254-255.
GALE WARNING UNTIL 6 AM EST MONDAY FOR ANZ256.
&&
$$
SYNOPSIS...BELK/FRANK
NEAR TERM...BELK
SHORT TERM...BELK
LONG TERM...FRANK
AVIATION...BELK/FRANK
MARINE...BELK/FRANK
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
332 AM CST Sun Dec 7 2014
.SHORT TERM...(Today)
ISSUED AT 331 AM CST SUN DEC 7 2014
Clouds have cleared out to the south tonight for now, but they are
lingering very close-by. Satellite images already confirm increasing
high clouds from the west. The HRRR is advertising a return of low
clouds from the east-southeast across the eastern half of the area
between 15z/9am and 18z/Noon today, but that seems a bit aggressive
based on the current progression of clouds across Indiana and the
expected wind patterns this morning. Have increased clouds from the
west based on satellite and model consensus, but only trended minor
increases in clouds across the east during the day for now. Will
monitor the movement of low clouds toward our eastern counties for
potential sky cover updates in the short term.
Northeast flow early this morning is expected to evolve to east and
then southeast this afternoon, as high pressure centered over the
Lake Michigan departs farther east across the Great Lakes. The onset
of southeast winds will increase the potential return of low clouds
currently lingering across southern IL.
Temperatures today will only climb about 12-13F above morning lows
due to increasing clouds, with highs topping out in the upper 30s
to low 40s.
&&
.LONG TERM...(Tonight through Saturday)
ISSUED AT 331 AM CST SUN DEC 7 2014
High pressure continues to build into the region, although clouds
continue to dominate the Midwest. Plenty of moisture on sat imagery
obscuring the llvl clouds underneath. Clearing in patches certainly
not anticipated for long as llvl moisture remains trapped by
continuing strong inversion over the area. The dry air aloft is not
coincident with enough turbulence to break up the inversion and
erode the higher RH at roughly 925 mb. This dry air will also be
the first issue for eroding the approaching precip late Sun night
and into Monday. Models maintaining consistency with the last two
runs and continuity with one another with regards to approach and
qpf after midnight tonight and into Monday. A quick front moving
through the area bringing precip after midnight and through the day
Monday so far looks like mostly rain, though the nrn tier of the
state may see a bit more of a rain/snow/wintry mix. Concern remains
whether or not the models are too quick to overcome the dry air
aloft or whether or not the precip may be delayed slightly.
Beyond Monday`s cold front, temps cool briefly, then moderate back
into the 40s for highs through the end of the week. 00z GFS
agreeing with yesterdays 00z ECMWF and backing down from the precip
Wed/Thursday, instead dominating the sfc map with high pressure.
Pops mid week have been removed. Deepening low over the
northeast/east coast causing a bit of a back up across the CONUS as
it is slow to move and the models having some issue with pushing the
new wave inland on the Pacific coast and managing the ridging in the
middle. Seems from Friday and into the weekend the forecast becomes
a bit more problematic in the details as the models work out a
pattern shift again.
&&
.AVIATION...(For the 06Z TAFS through 06Z Sunday night)
ISSUED AT 1122 PM CST SAT DEC 6 2014
VFR CONDITIONS SHOULD PREVAIL OVER THE TAF SITES THROUGH THE
PERIOD...WITH A SLIGHT EXCEPTION FOR SPI AS HAZE STILL LINGERS
REDUCING VIS TO MVFR. HOWEVER...DO NOT THINK THIS WILL STICK
AROUND VERY LONG SINCE UPSTREAM AT AAA VIS HAS ALREADY CLEARED OUT
ABOVE 6SM FROM THE HIGH PRESSURE BUILDING OVER THE GREAT LAKES.
THEREFORE...USED A TEMPO GROUP FOR THE NEXT HOUR TO ACCOUNT FOR
THE REDUCED VIS IMPROVING TO VFR WITHIN THE HOUR. OTHERWISE...HIGH
CLOUDS ARE MOVING IN OVER THE TAF SITES WITH THE NEXT STORM SYSTEM
OUT IN THE PLAINS. ALONG WITH HIGH CLOUDS STREAMING IN...WINDS
SHOULD BEGIN TO SHIFT TO THE EAST AND THEN SOUTHEAST BY TOMORROW.
CIGS APPEAR TO REMAIN VFR THROUGH THE TAF PERIOD ACCORDING TO
GUIDANCE AND SOUNDINGS. PIA...BMI...AND SPI COULD SEE VCSH
TOMORROW NIGHT AROUND 03Z/04Z...BUT NOT CONFIDENT ENOUGH IN RAIN
FALLING OVER THE SITES BEFORE 06Z TO INCLUDE ANYTHING ELSE. THIS CAN
BE UPDATED IN LATER TAF ISSUANCES IF NEEDED.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Shimon
LONG TERM...HJS
AVIATION...ALW
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1149 PM CST SAT DEC 6 2014
.SHORT TERM...
257 PM CST
NORTHEAST FLOW OVER THE REGION AHEAD OF HIGH PRESSURE HAS
CONTINUED TO EASE IN DRIER AIR. MID-AFTERNOON VISIBLE SATELLITE
IMAGERY REVEALS ONLY SOME DEPARTING STRATUS ACROSS THE FAR
SOUTHERN FORECAST AREA...AND SOME REMAINING RIBBONS OF LAKE EFFECT
CLOUDS INTO FAR NORTHEAST IL AND NORTHWEST IN. WATER VAPOR IMAGERY
CONFIRMS DRIER MID-LEVEL AIR AND SUPPRESSION MOVING OVERHEAD WHICH
SHOULD MITIGATE CLOUDS THIS EVENING...OUTSIDE OF A FEW LAKE
EFFECT CLOUDS INCHING WESTWARD OVER NORTHERN IL WITHIN THE
VEERING FLOW. A LIGHT WIND COMPONENT WILL REMAIN THIS EVENING
ALTHOUGH AS THE 1039 MB HIGH PASSES ACROSS WI...THE WINDS WILL
LIKELY BECOME LIGHT AND VARIABLE ALLOWING FOR FURTHER TEMPERATURE
DROP. DEW POINTS ARE SEVERAL DEGREES ABOVE THIS AT PRESENT...BUT
NOT REALLY A PATTERN WHERE WOULD EXPECT FOG...ESPECIALLY ANYTHING
OF NOTE.
SOUTHEAST WINDS WILL SETTLE IN ON SUNDAY WITH THE DEPARTING HIGH
AND LOW PRESSURE MARCHING EASTWARD NEAR THE NORTHERN CONUS BORDER.
HIGH CLOUDS LOOK TO GRADUALLY INCREASE/THICKEN DURING THE
AFTERNOON. GIVEN HIGHS TODAY REACHED THE UPPER 30S TO LOWER 40S
WOULD ENVISION SUNDAY BEING IN THE SAME ARENA IF CLOUDS DO NOT
THICKEN EARLIER THAN FORECAST.
MTF
&&
.LONG TERM...
315 PM CST
LONG TERM...SUNDAY NIGHT THROUGH SATURDAY...
OVERALL THE EXTENDED PERIOD WILL CONTINUE TO FEATURE A FAIRLY
PROGRESSIVE WEATHER PATTERN...WITH ONLY A QUICK HIT OF SOME COLDER
AIR FOR LATE TUESDAY INTO WEDNESDAY. THE MAIN FORECAST CONCERNS
DURING THE PERIOD WILL BE THE INCREASING POTENTIAL OF A QUICK HIT OF
WINTERY WEATHER LATE SUNDAY NIGHT INTO MONDAY MORNING.
WATER VAPOR IMAGERY INDICATES THE NEXT PACIFIC SYSTEM OF
INTEREST...NOW SHIFTING ONSHORE ACROSS WASHINGTON STATE. THIS
FEATURE...ALONG WITH AN ASSOCIATED AREA OF LOW PRESSURE IS EXPECTED
TO TRACK QUICKLY ALONG OR NEAR THE CANADIAN INTERNATIONAL
BORDER SUNDAY THROUGH TUESDAY. TYPICALLY THIS TYPE OF TRACK IS NOT
GOOD FOR MUCH PRECIPITATION FOR THE AREA...AND OVERALL THIS WILL BE
THE CASE. HOWEVER...IT APPEARS THAT QUICK HIT OF WINTRY PRECIPITATION
IS LIKELY LATE SUNDAY NIGHT INTO EARLY MONDAY MORNING.
A PERIOD OF INCREASING ISENTROPIC ASCENT COMBINED WITH SOME DECENT
Q-VECTOR CONVERGENCE...ASSOCIATED WITH ADDITIONAL SHORTWAVE ENERGY
DIGGING SOUTHEASTWARD TOWARDS THAT AREA LATER SUNDAY NIGHT...SHOULD
PROVIDE A SHORT PERIOD OF FORCING SUPPORTIVE OF PRECIPITATION ACROSS
NORTHERN ILLINOIS/NORTHWESTERN INDIANA. OVERALL...THIS STILL APPEARS
TO BE A SMALL EVENT FOR THE AREA. HOWEVER...IT APPEARS THAT A
STRENGTHENING BAROCLINIC ZONE ALONG AN OCCLUDED FRONTAL BOUNDARY MAY
PROVIDE A SHORT PERIOD OF ENHANCED MESOSCALE FORCING...SUPPORTIVE A
SHORT PERIOD OF HEAVIER PRECIPITATION...ESPECIALLY GIVEN THE PRESENCE
OF STEEP MID LEVEL LAPSE RATES INTO MONDAY MORNING. THUS...IT
APPEARS THAT BAND OF PRECIPITATION...POSSIBLY ONLY LASTING A COUPLE
HOURS AT ANY GIVEN LOCATION...IS LIKELY TO MOVE ACROSS THE AREA IN
TIME FOR THE MONDAY MORNING RUSH.
PRECIP TYPE STILL APPEARS TO BE TRICKY WITH THIS ACTIVITY EARLY
MONDAY. ASIDE FOR THE NAM SOLUTION...MOST MODEL DERIVED SOUNDINGS
ACROSS NORTHERN ILLINOIS INDICATE MAX LAYER TEMPERATURES OF ONLY +1
TO +1.5 DEGREES CELSIUS...WHICH WOULD SUGGEST ONLY PARTIAL MELTING OF
DENDRITES...POSSIBLY RESULTING IN SNOW AND SLEET PRECIP TYPES ACROSS
MOST OF FAR NORTHERN ILLINOIS. ALSO...GIVEN THAT THERE COULD BE SOME
ENHANCE PRECIP RATES WITH THIS ACTIVITY...AS WELL AS THE FACT THAT
EVAPORATIVE COOLING POTENTIAL SUNDAY NIGHT WILL BE HIGH...IT APPEARS
PRUDENT TO MENTION MORE OF A SNOW AND SLEET SCENARIO ACROSS FAR
NORTHERN ILLINOIS RATHER THAN FREEZING RAIN AT THIS POINT. THEREFORE...I
HAVE TRENDED THE FORECAST IN THIS DIRECTION.
ACCUMULATIONS ARE ALSO POSSIBLE WITH THIS ACTIVITY. IN FACT...SOME
AREAS COULD GET A QUICK INCH OF SNOW...IF IT FALLS PRIMARILY AS SUCH.
AT THIS TIME IT APPEARS THE BEST POTENTIAL FOR THIS APPEARS TO BE
ROUGHLY ALONG AND NORTH OF I-88 IN NORTHERN ILLINOIS. ALTHOUGH TOTAL
AMOUNTS WILL BE LIGHT...THE POSSIBILITY OF A QUICK HALF TO ONE INCH OF
SNOW RIGHT AROUND DAYBREAK MONDAY COULD CAUSE PROBLEMS FOR THE
MONDAY MORNING COMMUTE. AREAS SOUTH OF INTERSTATE 80 COULD SEE MORE
OF MIX BAG OF RAIN...FREEZING RAIN...SLEET AND SNOW GIVEN SLIGHTLY
WARMER MID LEVEL TEMPERATURES. SURFACE TEMPERATURES HERE MAY BE
HOVERING RIGHT AROUND FREEZING...SO QUESTIONS STILL RESIDE AROUND
HOW MUCH OF THIS PRECIP WILL BE FROZEN.
ONCE THIS BAND OF HEAVER PRECIP SHIFTS EAST OF THE AREA BY LATE
MORNING...IT APPEARS THAT THE MID LEVELS WILL DRY OUT
SUBSTANTIALLY...THUS ANY LINGERING PRECIP MONDAY AFTERNOON WOULD
LIKELY BE MORE DRIZZLY. THE COLDER SIDE OF THE STORM SYSTEM WILL
ARRIVE ACROSS THE REGION BY EARLY MONDAY EVENING...AS WINDS BECOME A
BIT GUSTY OUT OF THE WEST NORTHWEST. THIS SHOULD RESULT IN A COLDER
DAY ACROSS THE AREA ON TUESDAY. MOST AREAS WILL REMAIN DRY TUESDAY
AND TUESDAY NIGHT. HOWEVER...SOME LAKE EFFECT SNOW SHOWERS OR
FLURRIES ARE POSSIBLE ACROSS NORTHWESTERN INDIANA DURING THE DAY
TUESDAY. THEN AS THE LOWER LEVEL FLOW VEERS MORE NORTHERLY LATE
TUESDAY THESE LAKE EFFECT FLURRIES COULD GET INTO NORTHEASTERN
ILLINOIS TUESDAY EVENING. OVERALL...THIS DOES NOT APPEAR TO BE MUCH
OF A LAKE EFFECT EVENT AS LAKE INDUCED INVERSION HEIGHTS DO NOT
APPEAR VERY IMPRESSIVE...AND EVEN APPEAR TO REMAIN BELOW THE DENDRITIC
GROWTH ZONE.
THE WEATHER THE REST OF THE WEEK APPEARS TO BE FAIRLY QUIT...BUT ON
A WARMING TREND. MID LEVEL HEIGHT RISES ARE EXPECTED TO OVERSPREAD
MUCH OF THE CENTRAL CONUS LATER IN THE PERIOD IN RESPONSE TO THE
PERSISTENT NEGATIVE HEIGHT ANOMALIES ACROSS THE NORTHEASTERN PACIFIC
AND GULF OF ALASKA REGION SHIFTING EASTWARD TOWARDS THE WESTERN
NORTH AMERICAN COAST. THIS PARTICULARLY PATTERN STILL LOOKS TO BE
CONDUCE FOR A PERIOD OF MUCH ABOVE NORMAL TEMPERATURES NEXT FRIDAY
AND ESPECIALLY INTO SATURDAY. MODEL GUIDANCE HAS BEEN IN GOOD
AGREEMENT IN INDICATING THIS LARGER SCALE EL NINO-LIKE PATTERN
EVOLVING...AND GIVEN THAT THIS IS PATTERN KNOWN FOR PRODUCING MILD
CONDITIONS LOCALLY...CONFIDENCE IS ABOVE AVERAGE FOR THIS PERIOD TO
EXPERIENCE ABOVE AVERAGE TEMPERATURES. AT THIS TIME I HAVE REMAINED
A BIT CONSERVATIVE ON TEMPERATURES...ONLY WARMING THEM TO NEAR 50 FOR
SATURDAY. THIS COULD BE SEVERAL DEGREES TOO LOW IF THE CURRENT MODEL
FORECASTS PAN OUT. MOST GUIDANCE IS INDICATING 925 MB TEMPERATURES
ANYWHERE FROM +6 TO +10 DEGREES CELSIUS...WHICH COULD SUPPORT
TEMPERATURES INTO THE 50S BY NEXT SATURDAY UNDER A 570+ DM MID LEVEL
RIDGE.
KJB
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* SOUTHEAST WINDS AROUND 10 KT TODAY.
* LOWERING CIGS AND A PERIOD OF MIXED PRECIPITATION STARTING
AROUND OR JUST AFTER 12Z MONDAY.
MDB
//DISCUSSION...UPDATED 06Z...
HIGH PRESSURE IS OVERHEAD OF THE TERMINALS TONIGHT ALLOWING FOR
LIGHT NORTHEAST WINDS. WINDS WILL SWING AROUND TO THE SOUTHEAST
OVERNIGHT AND BE FAIRLY STEADY AROUND 10 KT DURING THE DAY. WINDS
WILL TURN TO THE SOUTH INTO MONDAY MORNING. VFR HIGH CLOUDS WILL
STREAM OVERHEAD THROUGH THE DAY TODAY AND TONIGHT BEFORE LOWERING
INTO MONDAY MORNING AHEAD OF A LOW PRESSURE SYSTEM/COLD FRONT. A
PERIOD OF MIXED PRECIPITATION IS EXPECTED MONDAY MORNING...LIKELY
STARTING JUST PRIOR TO 12Z AT RFD AND AROUND OR SOON AFTER 12Z AT
DPA/ORD/MDW/GYY. DETAILS ARE STILL IN FLUX BUT SOME SNOW/SLEET
ACCUMULATION IS POSSIBLE WITH A PERIOD OF IFR CIGS/VSBY POSSIBLE.
MDB
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* HIGH CONFIDENCE IN SOUTHEAST WINDS AROUND 10 KT TODAY.
* HIGH CONFIDENCE IN LOWERING CIGS AND A PERIOD OF MIXED
PRECIPITATION MONDAY MORNING.
MDB
//OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z...
MONDAY...CHANCE OF SLEET/SNOW MIX IN THE MORNING. MVFR/BRIEF IFR
POSSIBLE. S WINDS BECOMING W.
TUESDAY...VFR. NW WINDS BECOMING N.
WEDNESDAY...VFR. N WINDS BECOMING NE.
THURSDAY...VFR. S WINDS.
FRIDAY...VFR. S WINDS.
RATZER
&&
.MARINE...
222 PM CST
TONIGHT THROUGH SUNDAY
THE STIFF NORTHERLY WINDS ACROSS THE LAKE TODAY WILL EASE THIS
EVENING AND VEER EASTWARD BY OVERNIGHT. WAVES WILL SUBSIDE BELOW 5
FT BY LATE TONIGHT. THE PROGRESSIVE PATTERN CONTINUES WITH HIGH
PRESSURE ADVANCING OVER THE LAKE QUICKLY OVERNIGHT FOLLOWED BY
INFLUENCE OF APPROACHING LOW PRESSURE ALREADY BY SUNDAY WITH WINDS
TURNING SOUTHEASTERLY.
SUNDAY NIGHT ONWARD
STRONG HIGH PRESSURE SHIFTING EASTWARD FROM QUEBEC AND WEAK LOW
PRESSURE TRACKING EAST ALONG THE CANADIAN BORDER WILL REALLY TIGHTEN
THE PRESSURE GRADIENT AND CAUSE SOUTHEAST WINDS TO TURN SOUTH AND
STRENGTHEN ON SUNDAY NIGHT INTO MONDAY MORNING. LOOKING AT GUSTS
PRIMARILY UP TO 25 TO 30 KT OVER THE OPEN WATERS...BUT COULD SEE A
FEW GALE FORCE GUSTS ON NORTH HALF. COLD FRONT TRAILING FROM THE
WEAK LOW PRESSURE WILL CROSS THE LAKE MONDAY EVENING AND
NIGHT...FOLLOWED BY ANOTHER EXPANSIVE HIGH PRESSURE. WINDS WILL TURN
WEST-NORTHWEST MONDAY NIGHT TO NORTHERLY BY TUESDAY MORNING.
CURRENTLY EXPECTING SPEEDS/GUSTS UP TO 30 KT LATE MONDAY NIGHT
THROUGH TUESDAY...BUT AGAIN CANNOT RULE OUT A PERIOD OF GALES ON THE
NORTH TUESDAY MORNING WHEN PRESSURE RISES MAXIMIZE. NORTHERLY WINDS
WILL GRADUALLY DIMINISH ON TUESDAY NIGHT INTO WEDNESDAY AS THE HIGH
TRAVERSES THE LAKE...SHIFTING TO SOUTHWEST ON THURSDAY INTO THURSDAY
NIGHT ON THE BACK SIDE OF THE HIGH.
FOR THE NEARSHORE WATERS...SMALL CRAFT ADVISORY CRITERIA IS POSSIBLE
SUNDAY NIGHT INTO MONDAY MORNING...ESPECIALLY FOR THE ILLINOIS
SHORE. SMALL CRAFT CONDITIONS ARE THEN LIKELY TUESDAY MORNING INTO
WEDNESDAY.
MTF/RC
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 3 AM SUNDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
1132 PM CST Sat Dec 6 2014
.UPDATE...
ISSUED AT 822 PM CST SAT DEC 6 2014
The low clouds that plagued our area all day long have cleared all
but our far south and southeast counties this evening. However,
a large band of cirrus was streaming east into our area and will
be with us overnight and into most of Sunday. Temperatures for the
first few hours after skies cleared fell rapidly across the north
but have since steadied out some as the high level cloud cover
overspread the area. The latest surface map has a large area of
high pressure over central Wisconsin which is expected to push
east across the central Great Lakes over the next 24 hours keeping
our weather quiet. Have already sent out an update to address the
overnight temperatures across the north, with the remainder of
the forecast in good shape this evening.
&&
.SHORT TERM...(Tonight)
ISSUED AT 308 PM CST SAT DEC 6 2014
Clearing trend has finally started to make some headway southward
this afternoon, with the edge of the stratocumulus deck generally
along a Macomb to Peoria to Pontiac line at 230 pm. AWIPS timing
tool would suggest a position along I-72 in the 530-6 pm time frame,
while the HRRR is a bit slower around 8 pm. Additional erosion from
the northeast is indicated by the HRRR late evening, although at the
same time cirrus clouds will be streaming east from the Plains.
Thus, have mainly gone with a partly cloudy sky for tonight`s
forecast.
North/northeast flow to prevail into tonight, as high pressure
currently over Lake Superior settles southeast across the Great
Lakes. Temperatures expected to drop into the mid to upper 20s
overnight.
&&
.LONG TERM...(Sunday through Saturday)
ISSUED AT 308 PM CST SAT DEC 6 2014
High pressure will shift eastward from Illinois Sunday as a clipper
system approaches from the WNW. This system will start bringing
increasingly thick high clouds through the day Sunday, but the air
mass will generally remain quite dry in a layer from around 2000 to
12000 feet. This dry layer will take some time to saturate
overnight, which means only a slight chance for precipitation NW of
the Illinois River before midnight. These layers will saturate
through the night allowing a better chance for precipitation
reaching the surface mainly during the morning. Dry air will start
to move in aloft during the day Monday as the system shifts east of
the area, ending deep enough saturation for precipitation processes
to take place. Precipitation type looks to be largely rain for
central Illinois given a deep warm layer just off the surface. Still
some chance for light freezing rain with temperatures hovering very
near the freezing mark at the surface. Farther to the north, the
warm layer off the surface is less pronounced, which could allow for
snow or a mix of rain and snow to reach the surface..
A high pressure ridge will develop over the plains for much of the
week with NW flow and dry conditions for central IL. Temperatures
will remain below normal for much of the week as a result. Friday
and Saturday may see a substantial warmup as the plains ridge shifts
over IL. Only chance for precipitation in the extended forecast at
this time appears to be around Friday morning as a few models hint
at a weak disturbance meandering through the region at this time.
&&
.AVIATION...(For the 06Z TAFS through 06Z Sunday night)
ISSUED AT 1122 PM CST SAT DEC 6 2014
VFR CONDITIONS SHOULD PREVAIL OVER THE TAF SITES THROUGH THE
PERIOD...WITH A SLIGHT EXCEPTION FOR SPI AS HAZE STILL LINGERS
REDUCING VIS TO MVFR. HOWEVER...DO NOT THINK THIS WILL STICK
AROUND VERY LONG SINCE UPSTREAM AT AAA VIS HAS ALREADY CLEARED OUT
ABOVE 6SM FROM THE HIGH PRESSURE BUILDING OVER THE GREAT LAKES.
THEREFORE...USED A TEMPO GROUP FOR THE NEXT HOUR TO ACCOUNT FOR
THE REDUCED VIS IMPROVING TO VFR WITHIN THE HOUR. OTHERWISE...HIGH
CLOUDS ARE MOVING IN OVER THE TAF SITES WITH THE NEXT STORM SYSTEM
OUT IN THE PLAINS. ALONG WITH HIGH CLOUDS STREAMING IN...WINDS
SHOULD BEGIN TO SHIFT TO THE EAST AND THEN SOUTHEAST BY TOMORROW.
CIGS APPEAR TO REMAIN VFR THROUGH THE TAF PERIOD ACCORDING TO
GUIDANCE AND SOUNDINGS. PIA...BMI...AND SPI COULD SEE VCSH
TOMORROW NIGHT AROUND 03Z/04Z...BUT NOT CONFIDENT ENOUGH IN RAIN
FALLING OVER THE SITES BEFORE 06Z TO INCLUDE ANYTHING ELSE. THIS CAN
BE UPDATED IN LATER TAF ISSUANCES IF NEEDED.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Smith
SHORT TERM...Geelhart
LONG TERM...Onton
AVIATION...ALW
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
354 AM CST SUN DEC 7 2014
...UPDATED LONG TERM...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 202 AM CST SUN DEC 7 2014
WATER VAPOR LOOP INDICATING THE THE LATEST RAP AND NAM WERE DOING
A DECENT JOB ON THE TRACK OF AN UPPER LEVEL TROUGH AS IT MOVED
ACROSS EASTERN COLORADO EARLIER THIS MORNING. BOTH THE RAP AND NAM
MOVE THIS UPPER LEVEL FEATURE ACROSS WESTERN KANSAS BETWEEN 09Z
AND 15Z SUNDAY. MODEL SOUNDINGS INDICATING MOISTURE AHEAD OF THIS
UPPER LEVEL FEATURE WILL BE AT OR ABOVE THE 800MB LEVEL. IN
ADDITION TO THIS AREA OF MOISTURE THE SURFACE TO 1000 TO 2000FT
AGL LAYER WILL ALSO BE SATURATED EARLY THIS MORNING WITH THE
DEEPER LOW LEVEL MOISTURE APPEARING TO BE NEAR AND EAST OF HIGHWAY
283. BASED ON MODEL SOUNDINGS THE DEPTH OF THE LOW LEVEL MOISTURE
DOES NOT APPEAR DEEP ENOUGH TO SUPPORT DRIZZLE, HOWEVER WEAK LIFT
AHEAD OF THE UPPER LEVEL TROUGH MAY GIVE RISE TO SOME SPRINKLES OR
EVEN A BRIEF RAIN SHOWER...MAINLY IN NORTH CENTRAL AND SOUTH
CENTRAL KANSAS. WILL THEREFORE RETAIN SMALL CHANCE FOR
PRECIPITATION EARLY THIS MORNING EAST OF HIGHWAY 283.
WIDESPREAD STATUS AND FOG WILL BE LIKELY EARLY THIS MORNING. AT
THIS TIME THE AREA FAVORABLE FOR THE LOWER VISIBILITIES WILL BE
EAST OF HIGHWAY 83 THROUGH 15Z SUNDAY GIVEN THE LOW LEVEL MOISTURE
PROFILES AND BETTER UPSLOPE FLOW. BASED ON THE LATEST RAP AND HRRR
ALONG WITH MOST RECENT SURFACE OBSERVATIONS THE CURRENT DENSE FOG
ADVISORY HAS A GOOD HANDLE ON THIS SO NO MAJOR ADJUSTMENTS PLANNED
THIS MORNING. WILL CONTINUE TO MONITOR THIS AND ADJUST
ACCORDINGLY.
SUBSIDENCE DEVELOPING BEHIND THE UPPER LEVEL TROUGH DURING THE
LATE MORNING AND EARLY AFTERNOON WILL ALLOW FOR SOME AFTERNOON
SUNSHINE TO DEVELOP. AT THIS TIME CONFIDENCE IS NOT HIGH ON HOW
QUICKLY THE SKIES WILL CLEAR EAST OF DODGE CITY, HOWEVER BASED ON
THE NAM AND RAP TIMING OF THE CLEARING TREND FROM WEST TO EAST
ALONG WITH THE 850MB TEMPERATURES AT 21Z SUNDAY AND 00Z MONDAY THE
PREVIOUS FORECAST STILL LOOKS ON TRACK. WILL CONTINUE TO FAVOR THE
WARMER MAV GUIDANCE FOR HIGHS WEST OF ROUGHLY HIGHWAY 83 WHERE
MORE SUN THAN CLOUDS ARE EXPECTED DURING THE AFTERNOON. FURTHER
EAST FAVORED THE COOLER MET.
A SURFACE BOUNDARY WILL DROP SOUTH ACROSS WESTERN KANSAS LATE THIS
AFTERNOON AND EARLY TONIGHT. AS THIS BOUNDARY PASSES A
NORTHWESTERLY FLOW WILL DEVELOP AND DRIER AIR WILL RETURN TO
WESTERN KANSAS IN THE 0-1KM AGL LEVEL. BASED ON WESTERLY WINDS AT
10 KNOTS OR LESS AND DRIER AIR ADVECTING INTO WESTERN KANSAS WILL
THE PREVIOUS FORECAST WITH LOWS IN THE UPPER 20S TO LOWER 30S
STILL LOOKS ON TRACK.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 353 AM CST SUN DEC 7 2014
THE REST OF THE EXTENDED PERIOD IS SIMILAR TO THE LAST SEVERAL DAYS
AS FAR AS TEMPERATURES ARE CONCERNED, WITH RELATIVELY LOW IMPACT
SYNOPTIC SCALE WAVES EVERY COUPLE OF DAYS. DRIER AIR ALOFT WILL
INFLUENCE THE AREA MONDAY ON THE HEELS OF THE EXITING UPPER JET.
SUNNY SKY AND LIGHT SURFACE WINDS WILL LEAD TO TEMPERATURES MAINLY
INFLUENCED BY DIURNAL INSOLATION, WHILE EASTERLY SURFACE WINDS
DEVELOP OVERNIGHT INTO EARLY TUESDAY. SOME FOG OR STRATUS COULD
DEVELOP IN THE FAR WESTERN SECTIONS NEAR THE COLORADO LINE, BUT THIS
WOULD BE FAIRLY LIMITED AS OPPOSED THE MORE WIDESPREAD FOG OF LAST
NIGHT. THE ECMWF IS MORE AGGRESSIVE THAN THE GFS IN DEVELOPING RAIN
SHOWERS WITH THE POSITIVELY TILTED WAVE ON WEDNESDAY. FOR NOW LOW
PROBABILITIES EXIST FOR CENTRAL KANSAS WHERE BETTER MOISTURE SHOULD
BE PRESENT AS WELL AS BETTER STRETCHING DEFORMATION WITH THIS
PATTERN.
CONSIDERABLE UNCERTAINTY IN MESOSCALE DETAIL FOLLOWS BEYOND
WEDNESDAY AS THE ECMWF AND GFS BOTH AGREE ON AN INCOMING SYNOPTIC
LOW APPROACHING THE REGION WITH SOUTHERLY BOUNDARY LAYER WINDS. THE
DIFFERENCES EXIST IT A FAR MORE MOIST, STRATUS AND FOG TYPE PATTERN
OF THE EC AND MORE DRY BOUNDARY LAYER OR WESTERN KS WITH THE GFS
WHICH CAN ALSO MAKE LARGE DIFFERENCES IN EXPECTED TEMPERATURES.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1120 PM CST SAT DEC 6 2014
LIFR CONDITIONS CAN BE EXPECTED AT DDC AND HYS OVERNIGHT AS A
MOIST SOUTHEASTERLY UPSLOPE FLOW CONTINUES AT 10 TO 15 KNOTS
ACROSS WESTERN KANSAS. CEILINGS AND VISIBILITIES AT GCK ARE ALSO
EXPECTED TO FALL BACK INTO THE LOW IFR/LIFR CATEGORY BY 08Z BASED
ON THE LATEST HRRR, RAP AND NAM. AN UPPER LEVEL DISTURBANCE WILL
CROSS THE CENTRAL PLAINS EARLY SUNDAY AND A SURFACE BOUNDARY,
LOCATED NEAR THE COLORADO BORDER AT 05Z, WILL INTO WESTERN KANSAS.
AS THE LOW LEVEL WINDS VEER TO THE SOUTHWEST THE VISIBILITIES AND
CEILINGS WILL IMPROVE. CONFIDENCE IS NOT HIGH ON TIMING BUT GIVEN
THE LATEST HRRR, RAP AND NAM WILL FAVOR IFR/MVFR AT GCK AND HYS
BETWEEN 12 AND 15Z SUNDAY. FOR DDC WILL KEEP IFR CONDITIONS UNTIL
LATE MORNING. VFR CONDITIONS ARE EXPECTED TO DEVELOP IN THE
AFTERNOON AS SUBSIDENCE DEVELOPS BEHIND THE UPPER LEVEL TROUGH.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 58 31 58 32 / 10 0 0 0
GCK 60 28 58 30 / 10 0 0 0
EHA 63 33 60 36 / 0 0 0 0
LBL 60 30 59 31 / 10 0 0 0
HYS 55 29 56 28 / 10 0 0 0
P28 57 33 58 33 / 10 0 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 9 AM CST THIS MORNING FOR KSZ030-031-
043>046-063>066-076>081-086>090.
&&
$$
SHORT TERM...BURGERT
LONG TERM...RUSSELL
AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS GOODLAND KS
230 AM MST SUN DEC 7 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 207 PM MST SAT DEC 6 2014
EARLY AFTERNOON WV IMAGERY AND RAP H5 ANALYSIS SHOW PROGRESSIVE
TROUGH-RIDGE TROUGH PATTERN ACROSS US WITH RIDGE CURRENTLY
EXTENDING FROM SOUTH CENTRAL CANADA ACROSS THE CENTRAL PLAINS. SW
FLOW IS IN PLACE FROM THE FOUR CORNERS REGION AND INTO WESTERN KS
WITH SHORTWAVE TROUGH MOVING OUT OF THE GREAT BASIN TOWARDS THE
CENTRAL ROCKIES. AT THE SURFACE LEE TROUGH IS IN PLACE OVER
EASTERN COLORADO WITH SOUTHERLY FLOW ACROSS OUR CWA.
AS SHORTWAVE TROUGH TRANSITIONS EASTWARD STATIONARY
FRONT/BAROCLINIC ZONE WITH SHIFT NORTH AND EAST ALLOWING FOR
SOUTHEAST MOISTURE RETURN INTO THE EASTERN HALF OF OUR CWA.
MIDLEVEL MOISTURE/UPPER LEVEL FORCING COULD ALLOW FOR A BRIEF
PERIOD OF LIGHT RAIN SHOWERS LATE TONIGHT...HOWEVER MODEL
SOUNDINGS INDICATE A SIGNIFICANT DRY LAYER WOULD LIKELY PREVENT
ANY ELEVATED PRECIPITATION FROM REACHING THE SURFACE.
MAIN CONCERN WILL BE POTENTIAL FOR DENSE FOG DEVELOPMENT AND
POTENTIAL FOR DRIZZLE ACROSS EASTERN CWA LATE TONIGHT THROUGH
SUNDAY MORNING. NAM/RAP SHOW WEAK SURFACE CONVERGENCE IN PROXIMITY
OF BAROCLINIC ZONE WHICH COULD PROVIDE ENOUGH LIFT WITHIN SHALLOW
SATURATED LAYER TO ALLOW FOR DRIZZLE DEVELOPMENT. THIS COULD BE
MORE OF A STRATUS/DRIZZLE EVENT...THOUGH CONSIDERING THE GOOD
MOISTURE RETURN LOWER VISIBILITIES ARE CERTAINLY POSSIBLE. HIGH
CLOUDS HAVE ALREADY BEEN HAVING AN IMPACT ON MIXING THIS
AFTERNOON...AND WITH THICKENING/LOWERING CLOUDS THOUGH THE NIGHT
(ALONG WITH TD VALUES INCREASING TO MID/UPPER 30S IN THE
EAST)...RADIATIONAL COOLING WILL BE LIMITED. NOT ONLY COULD THIS
LIMIT DENSE FOG DEVELOPMENT...BUT THIS MAKES FREEZING
FOG/FREEZING DRIZZLE UNLIKELY AT THIS POINT. AT THIS POINT HOLDING
OFF ON HIGHLIGHTS SEEMS THE BEST COURSE.
WITH SHIFT BACK TO SW FLOW AS SHORTWAVE RIDGING BUILDS BACK INTO
THE ROCKIES THERE SHOULD BE RAPID IMPROVEMENT IN CONDITIONS
SUNDAY.CLEARING SKIES AND WAA THROUGH THE AFTERNOON SHOULD ALLOW
HIGHS TO WARM TO AROUND 60F...THOUGH STRATUS MAY HOLD ON A LITTLE
LONGER IN OUR EASTERN CWA LIMITING DAYTIME MIXING AND KEEPING
HIGHS IN THE LOW TO MID 50S.
.LONG TERM...(WEDNESDAY THROUGH SATURDAY)
ISSUED AT 230 AM MST SUN DEC 7 2014
A SIGNIFICANT WEATHER SYSTEM MAY AFFECT THE HIGH PLAINS LATE NEXT
WEEKEND. THIS SYSTEM IS THE MAIN EXTENDED FORECAST CONCERN AND THE
MAJORITY OF THIS DISCUSSION WILL FOCUS ON THE POSSIBILITIES.
FOR WEDNESDAY THROUGH SATURDAY...RIDGE OF HIGH PRESSURE ALOFT SHALL
DOMINATE THE WEATHER PATTERN. OVERALL...STILL ANTICIPATING VERY WARM
TEMPERATURES FOR THIS TIME OF YEAR. HOWEVER...FORECAST GUIDANCE HAS
LOWERED TEMPERATURES SLIGHTLY. UPON FURTHER REVIEW...IT APPEARS THE
MODELS ARE STRUGGLING WITH MOISTURE ADVECTION FROM THE SOUTH AND
SUBSEQUENT LOW CLOUDS...ESPECIALLY OVER THE EASTERN FORECAST REGION.
FELT CONFIDENT ENOUGH IN CONTINUING THE WARM FORECAST OVER THE WEST
AS DRIER AIR SHOULD REMAIN IN PLACE WITH DOWNSLOPE FLOW FROM THE
FRONT RANGE. FURTHER EAST...MORNING FOG/STATUS AND HIGHER MOISTURE
CONTENT OF ATMOSPHERE MAY LIMIT DAYTIME WARMING...THUS LEADING TO
COOLER HIGH TEMPERATURES.
CONCERNING NEXT WEEKENDS SYSTEM...MODELS HAVE BEEN CONSISTENT IN
SHOWING AT LEAST A STRONG DISTURBANCE MOVING THROUGH THE
SOUTHWESTERN UNITED STATES SATURDAY. THIS SYSTEM THEN EJECTS
NORTHEAST ACROSS THE HIGH PLAINS SUNDAY. MANY ASPECTS OF THIS SYSTEM
STILL NEED TO BE RESOLVED INCLUDING STRENGTH...TIMING AND MOST
PROBLEMATIC...PATH THIS SYSTEM TRAVELS. FORECAST ENSEMBLES INDICATE
A SIGNIFICANT AMOUNT OF SPREAD BETWEEN ENSEMBLE MEMBERS. THE
ENSEMBLE MEAN INDICATES A LARGE...OPEN TROUGH PASSING THROUGH WHILE
SOME OF THE MEMBERS AND THE 00Z OPERATIONAL GFS INDICATE A
STRONG...CLOSED LOW. THE OPERATIONAL EUROPEAN MODEL INDICATES THE
OPEN THOUGH SOLUTION SHOWN BY THE ENSEMBLE MEAN. THE EUROPEAN
ENSEMBLE ALSO SUGGESTS THE OPEN TROUGH SOLUTION BUT INDICATES A HIGH
VARIABILITY BETWEEN SOLUTIONS.
THE CLOSED LOW SOLUTION/POSSIBILITY IS EYE-OPENING IN THAT IT IS A
CLIMATOLOGICALLY FAVORABLE PATTERN FOR OUR REGION TO RECEIVE A
SIGNIFICANT WINTER STORM...POSSIBLY EVEN A BLIZZARD. THAT BEING
SAID...THERE IS JUST TOO MUCH VARIABILITY BETWEEN INDIVIDUAL MODELS
AND MODEL RUNS TO REALLY BEGIN HIGHLIGHTING A POTENTIAL HIGH-IMPACT
STORM. FOR EXAMPLE...YESTERDAYS 00Z GFS RUN SUGGESTED A STRONG
SYSTEM GOING SOUTH OF THE REGION...ACROSS THE BIG BEND COUNTRY OF
TEXAS. THE 06Z RUN SHOWED A STRONG SYSTEM EJECTING OVER THE COLORADO
FRONT RANGE AND HEADING TOWARDS RAPID CITY...WELL NORTH OF THE
FORECAST AREA. TODAYS 00Z OPERATIONAL GFS RUN BRINGS THE STRONG LOW
OVER THE TEXAS AND OKLAHOMA PANHANDLES WITH SIGNIFICANT AMOUNTS OF
PRECIPITATION ACROSS WESTERN KANSAS.
AS OF RIGHT NOW...AM FAIRLY CONFIDENT THAT A COLD FRONT WILL PASS
THROUGH AND WE HAVE A DECENT CHANCE AT SOME PRECIPITATION. HOW
MUCH...WHAT PRECIPITATION TYPE AND IF HIGH WINDS WILL ACCOMPANY THIS
SYSTEM IS EXTREMELY DIFFICULT TO PINPOINT AS OF RIGHT NOW DUE TO THE
DIFFERING POSSIBILITIES ON SYSTEM EVOLUTION. IT IS SOMETHING TO
WATCH FORECASTS UPDATES SO STAY TUNED!
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1000 PM MST SAT DEC 6 2014
KGLD...SOUTH WIND AROUND 15KTS AT TAF ISSUANCE WILL VEER TO THE
SOUTH AND DECREASE TO 10KTS BY 08Z UNDER A VFR OVERCAST SKY. STRATUS/BR
MAY REACH THE TERMINAL FROM THE EAST/SOUTHEAST AROUND 08Z WITH
IFR CIGS EXPECTED FROM 08Z-11Z WITH WINDS FROM THE SOUTH AROUND
10KTS. AROUND 12Z WINDS VEER TO THE SOUTHWEST 5-10KTS PUSHING THE
STRATUS SLOWLY EAST ALLOWING FOR VFR CONDITIONS TO RETURN. WINDS
THEN GO WEST UNDER 10KTS AROUND 15Z THEN SHIFT TO THE NORTHWEST
12G20KT POSSIBLY A BIT HIGHER IN THE 18Z-22Z TIMEFRAME UNDER JUST
A FEW FAIR WEATHER CLOUDS. BY 23Z WINDS DISSIPATE TO 5KTS OR SO BY
23Z THEN BACK TO THE WEST AT SIMILAR SPEEDS AROUND 05Z.
KMCK...SOUTHEAST WIND NEAR 10KT AT TAF ISSUANCE UNDER A VFR
OVERCAST SKY. STRATUS/DRIZZLE/BR WITH IFR CONDITIONS AND POSSIBLY
VLIFR CONDITIONS WITH VIS 1/2SM IN FG/DZ REACH THE TERMINAL FROM
THE EAST AROUND 09Z AND CONTINUE THROUGH 17Z BEFORE WINDS VEER
AROUND TO THE NORTHWEST NEAR 10KTS IN THE 17Z-20Z TIMEFRAME. THIS
WILL SCOUR OUT THE STRATUS PRODUCING VFR CONDITIONS FROM 17Z
THROUGH THE REST OF THE TAF PERIOD.
IT SHOULD BE NOTED THAT IN THESE SCENARIOS THAT HIGH RESOLUTION
MODELS OCCASIONALLY DONT PUSH THE STRATUS FAR ENOUGH WEST...BY AT
LEAST ONE ROW OF COUNTIES. IF THIS VERIFIES STRATUS/BR (POSSIBLY
FG WITH VLIFR CONDITIONS) MAY TAKE UP TO AN ADDITIONAL 3 HOURS TO
MOVE OUT OF BOTH TERMINALS. WITH A THICK OVERCAST SKY HARD TO
WATCH STRATUS PROGRESSION ON SATELLITE IMAGERY SO WILL HAVE TO
WATCH METARS AND HOURLY MODEL UPDATES FROM THE RUC AND HRRR.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...RRH
AVIATION...99
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
204 AM CST SUN DEC 7 2014
...UPDATED SHORT TERM DISCUSSION...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 202 AM CST SUN DEC 7 2014
WATER VAPOR LOOP INDICATING THE THE LATEST RAP AND NAM WERE DOING
A DECENT JOB ON THE TRACK OF AN UPPER LEVEL TROUGH AS IT MOVED
ACROSS EASTERN COLORADO EARLIER THIS MORNING. BOTH THE RAP AND NAM
MOVE THIS UPPER LEVEL FEATURE ACROSS WESTERN KANSAS BETWEEN 09Z
AND 15Z SUNDAY. MODEL SOUNDINGS INDICATING MOISTURE AHEAD OF THIS
UPPER LEVEL FEATURE WILL BE AT OR ABOVE THE 800MB LEVEL. IN
ADDITION TO THIS AREA OF MOISTURE THE SURFACE TO 1000 TO 2000FT
AGL LAYER WILL ALSO BE SATURATED EARLY THIS MORNING WITH THE
DEEPER LOW LEVEL MOISTURE APPEARING TO BE NEAR AND EAST OF HIGHWAY
283. BASED ON MODEL SOUNDINGS THE DEPTH OF THE LOW LEVEL MOISTURE
DOES NOT APPEAR DEEP ENOUGH TO SUPPORT DRIZZLE, HOWEVER WEAK LIFT
AHEAD OF THE UPPER LEVEL TROUGH MAY GIVE RISE TO SOME SPRINKLES OR
EVEN A BRIEF RAIN SHOWER...MAINLY IN NORTH CENTRAL AND SOUTH
CENTRAL KANSAS. WILL THEREFORE RETAIN SMALL CHANCE FOR
PRECIPITATION EARLY THIS MORNING EAST OF HIGHWAY 283.
WIDESPREAD STATUS AND FOG WILL BE LIKELY EARLY THIS MORNING. AT
THIS TIME THE AREA FAVORABLE FOR THE LOWER VISIBILITIES WILL BE
EAST OF HIGHWAY 83 THROUGH 15Z SUNDAY GIVEN THE LOW LEVEL MOISTURE
PROFILES AND BETTER UPSLOPE FLOW. BASED ON THE LATEST RAP AND HRRR
ALONG WITH MOST RECENT SURFACE OBSERVATIONS THE CURRENT DENSE FOG
ADVISORY HAS A GOOD HANDLE ON THIS SO NO MAJOR ADJUSTMENTS PLANNED
THIS MORNING. WILL CONTINUE TO MONITOR THIS AND ADJUST
ACCORDINGLY.
SUBSIDENCE DEVELOPING BEHIND THE UPPER LEVEL TROUGH DURING THE
LATE MORNING AND EARLY AFTERNOON WILL ALLOW FOR SOME AFTERNOON
SUNSHINE TO DEVELOP. AT THIS TIME CONFIDENCE IS NOT HIGH ON HOW
QUICKLY THE SKIES WILL CLEAR EAST OF DODGE CITY, HOWEVER BASED ON
THE NAM AND RAP TIMING OF THE CLEARING TREND FROM WEST TO EAST
ALONG WITH THE 850MB TEMPERATURES AT 21Z SUNDAY AND 00Z MONDAY THE
PREVIOUS FORECAST STILL LOOKS ON TRACK. WILL CONTINUE TO FAVOR THE
WARMER MAV GUIDANCE FOR HIGHS WEST OF ROUGHLY HIGHWAY 83 WHERE
MORE SUN THAN CLOUDS ARE EXPECTED DURING THE AFTERNOON. FURTHER
EAST FAVORED THE COOLER MET.
A SURFACE BOUNDARY WILL DROP SOUTH ACROSS WESTERN KANSAS LATE THIS
AFTERNOON AND EARLY TONIGHT. AS THIS BOUNDARY PASSES A
NORTHWESTERLY FLOW WILL DEVELOP AND DRIER AIR WILL RETURN TO
WESTERN KANSAS IN THE 0-1KM AGL LEVEL. BASED ON WESTERLY WINDS AT
10 KNOTS OR LESS AND DRIER AIR ADVECTING INTO WESTERN KANSAS WILL
THE PREVIOUS FORECAST WITH LOWS IN THE UPPER 20S TO LOWER 30S
STILL LOOKS ON TRACK.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 232 PM CST SAT DEC 6 2014
A MILD PERIOD IS FORECAST AHEAD OF THE NEXT UPPER LEVEL TROUGH AND
STORM SYSTEM PUSHING INTO THE WESTERN U.S. BY NEXT WEEKEND. GFS
ENSEMBLES ARE A BIT MORE AGGRESSIVE AND STRONGER THAN THE EUROPEAN
MODEL WITH THIS NEXT SYSTEM THAT COULD BE A WEATHER MAKER INTO THE
PLAINS AROUND THE 15TH AND 16TH OF DECEMBER.
FOR MONDAY, LIGHT AND VARIABLE WINDS BECOME LIGHT SOUTHEASTERLY WITH
HIGHS IN THE MID AND UPPER 50S. FOR TUESDAY, SOUTHERLY WINDS
INCREASE AHEAD OF A LEE TROUGH, WITH HIGHS AGAIN FROM 55 TO 60. ON
WEDNESDAY, AN UPPER LEVEL TROUGH BRINGS A COLD FRONT ACROSS WESTERN
KANSAS IN THE MORNING INTO THE AFTERNOON. THERE COULD BE
CONSIDERABLE LOW CLOUDS AND SOME FOG AHEAD OF THIS FRONT ON
WEDNESDAY AS DEWPOINTS RISE INTO THE 40S. SOME LIGHT RAIN SHOWERS
MAY BREAK OUT IN PARTS OF SOUTH CENTRAL KANSAS, MAINLY EAST OF DODGE
CITY AHEAD OF THE COLD FRONT. HIGHS ON WEDNESDAY WILL CONTINUE TO BE
IN THE 50S. OVERNIGHT LOWS MONDAY MORNING WILL RANGE FROM THE MID
AND UPPER 20S ACROSS SOUTHWEST KANSAS TO THE LOW TO MID 30S NEAR
MEDICINE LODGE. LOWS THEN WARM BACK INTO THE MID 30S INTO THURSDAY
MORNING.
FOR THE PERIOD OF THURSDAY INTO SATURDAY, UPPER LEVEL RIDGING AND
WARMING MOVE INTO THE PLAINS AHEAD OF THE NEXT STORM SYSTEM PUSHING
INTO THE WESTERN U.S. HIGHS WILL BE MILD AND IN THE MID 50S TO LOW
60S. LOWS WILL BE IN THE 30S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1120 PM CST SAT DEC 6 2014
LIFR CONDITIONS CAN BE EXPECTED AT DDC AND HYS OVERNIGHT AS A
MOIST SOUTHEASTERLY UPSLOPE FLOW CONTINUES AT 10 TO 15 KNOTS
ACROSS WESTERN KANSAS. CEILINGS AND VISIBILITIES AT GCK ARE ALSO
EXPECTED TO FALL BACK INTO THE LOW IFR/LIFR CATEGORY BY 08Z BASED
ON THE LATEST HRRR, RAP AND NAM. AN UPPER LEVEL DISTURBANCE WILL
CROSS THE CENTRAL PLAINS EARLY SUNDAY AND A SURFACE BOUNDARY,
LOCATED NEAR THE COLORADO BORDER AT 05Z, WILL INTO WESTERN KANSAS.
AS THE LOW LEVEL WINDS VEER TO THE SOUTHWEST THE VISIBILITIES AND
CEILINGS WILL IMPROVE. CONFIDENCE IS NOT HIGH ON TIMING BUT GIVEN
THE LATEST HRRR, RAP AND NAM WILL FAVOR IFR/MVFR AT GCK AND HYS
BETWEEN 12 AND 15Z SUNDAY. FOR DDC WILL KEEP IFR CONDITIONS UNTIL
LATE MORNING. VFR CONDITIONS ARE EXPECTED TO DEVELOP IN THE
AFTERNOON AS SUBSIDENCE DEVELOPS BEHIND THE UPPER LEVEL TROUGH.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 58 31 58 32 / 10 0 0 0
GCK 60 28 58 30 / 10 0 0 0
EHA 63 33 60 36 / 0 0 0 0
LBL 60 30 59 31 / 10 0 0 0
HYS 55 29 56 28 / 10 0 0 0
P28 57 33 58 33 / 10 0 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 9 AM CST THIS MORNING FOR KSZ030-031-
043>046-063>066-076>081-086>090.
&&
$$
SHORT TERM...BURGERT
LONG TERM...KRUSE
AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1122 PM CST SAT DEC 6 2014
...UPDATED SYNOPSIS AND AVIATION DISCUSSION...
.SYNOPSIS...
ISSUED AT 1120 PM CST SAT DEC 6 2014
AT 00Z SUNDAY A 500MB TROUGH WAS LOCATED NEAR THE FOUR CORNERS
REGION WITH A +90KNOT 250MB JET STREAK EXTENDING FROM THE BASED OF
THIS UPPER LEVEL TROUGH INTO SOUTHWEST KANSAS. A SURFACE TROUGH OF
LOW PRESSURE WAS LOCATED ALONG THE LEE OF THE ROCKIES AT 00Z
SUNDAY AND A SURFACE HIGH EXTENDED FROM THE NORTHERN MISSISSIPPI
VALLEY INTO NORTH TEXAS. A SOUTH TO SOUTHEASTERLY FLOW WAS PRESENT
OVER WESTERN KANSAS WITH SURFACE DEWPOITNS IN THE MID TO UPPER 30S
EVIDENT UPSTREAM IN OKLAHOMA.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 1217 PM CST SAT DEC 6 2014
SHORT RANGE MODELS INDICATE A WEAK UPPER LEVEL RIDGE TRANSITIONING
EAST ACROSS THE CENTRAL PLAINS TONIGHT AS AN UPPER LEVEL SHORTWAVE
MOVES EAST ACROSS THE DESERT SOUTHWEST INTO THE SOUTHERN ROCKIES.
MEANWHILE, A BROAD AREA OF HIGH PRESSURE STRETCHING FROM THE UPPER
MIDWEST DOWN INTO KANSAS WILL SHIFT EAST TONIGHT BRINGING ABOUT A
SOUTHEASTERLY UPSLOPE FLOW TO WESTERN KANSAS. ALTHOUGH THE FLOW
ALOFT IS EXPECTED TO WEAKEN THROUGH EARLY SUNDAY MORNING, ENOUGH
LIFT COMBINED WITH INCREASING LOW/MID LEVEL MOISTURE MAY LEAD TO
THE DEVELOPMENT OF FOG ACCOMPANIED BY LIGHT DRIZZLE/SPRINKLES
LATE TONIGHT AS THE SHORTWAVE KICKS OUT OF THE SOUTHERN ROCKIES
INTO THE WESTERN HIGH PLAINS. OTHERWISE, SIGNIFICANT PRECIP
AMOUNTS ARE NOT EXPECTED. DRIER CONDITIONS ARE LIKELY ACROSS
WESTERN KANSAS BY SUNDAY AFTERNOON AS THE SHORTWAVE MOVES FURTHER
EAST.
TEMPERATURES WILL BE ABOVE NORMAL TONIGHT AS A SOUTHEASTERLY UPSLOPE
FLOW QUICKLY DEVELOPS DRAWING INCREASED MOISTURE UP INTO THE REGION.
AS SURFACE DEWPOINTS CLIMB WELL INTO THE 20S(F) AND LOWER 30S(F),
LOOK FOR LOWS ONLY DOWN INTO THE MID TO UPPER 30S(F) TONIGHT. A
DEVELOPING LEE SIDE TROUGH EARLY SUNDAY MORNING WILL STRENGTHEN
THROUGHOUT THE DAY TURNING THE LOW LEVEL FLOW MORE SOUTH TO
SOUTHWESTERLY. THIS WILL ENHANCE WARM AIR ADVECTION INTO WESTERN
KANSAS WITH H85 TEMPERATURES CLIMBING UP NEAR 8C TO 10C ACROSS
CENTRAL AND SOUTHWEST KANSAS. EXPECT HIGHS WELL UP INTO THE 50S(F)
ACROSS CENTRAL KANSAS TO THE LOWER AND MID 60S(F) IN EXTREME
SOUTHWEST KANSAS WHERE SOME DOWNSLOPING MAY OCCUR.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 232 PM CST SAT DEC 6 2014
A MILD PERIOD IS FORECAST AHEAD OF THE NEXT UPPER LEVEL TROUGH AND
STORM SYSTEM PUSHING INTO THE WESTERN U.S. BY NEXT WEEKEND. GFS
ENSEMBLES ARE A BIT MORE AGGRESSIVE AND STRONGER THAN THE EUROPEAN
MODEL WITH THIS NEXT SYSTEM THAT COULD BE A WEATHER MAKER INTO THE
PLAINS AROUND THE 15TH AND 16TH OF DECEMBER.
FOR MONDAY, LIGHT AND VARIABLE WINDS BECOME LIGHT SOUTHEASTERLY WITH
HIGHS IN THE MID AND UPPER 50S. FOR TUESDAY, SOUTHERLY WINDS
INCREASE AHEAD OF A LEE TROUGH, WITH HIGHS AGAIN FROM 55 TO 60. ON
WEDNESDAY, AN UPPER LEVEL TROUGH BRINGS A COLD FRONT ACROSS WESTERN
KANSAS IN THE MORNING INTO THE AFTERNOON. THERE COULD BE
CONSIDERABLE LOW CLOUDS AND SOME FOG AHEAD OF THIS FRONT ON
WEDNESDAY AS DEWPOINTS RISE INTO THE 40S. SOME LIGHT RAIN SHOWERS
MAY BREAK OUT IN PARTS OF SOUTH CENTRAL KANSAS, MAINLY EAST OF DODGE
CITY AHEAD OF THE COLD FRONT. HIGHS ON WEDNESDAY WILL CONTINUE TO BE
IN THE 50S. OVERNIGHT LOWS MONDAY MORNING WILL RANGE FROM THE MID
AND UPPER 20S ACROSS SOUTHWEST KANSAS TO THE LOW TO MID 30S NEAR
MEDICINE LODGE. LOWS THEN WARM BACK INTO THE MID 30S INTO THURSDAY
MORNING.
FOR THE PERIOD OF THURSDAY INTO SATURDAY, UPPER LEVEL RIDGING AND
WARMING MOVE INTO THE PLAINS AHEAD OF THE NEXT STORM SYSTEM PUSHING
INTO THE WESTERN U.S. HIGHS WILL BE MILD AND IN THE MID 50S TO LOW
60S. LOWS WILL BE IN THE 30S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1120 PM CST SAT DEC 6 2014
LIFR CONDITIONS CAN BE EXPECTED AT DDC AND HYS OVERNIGHT AS A
MOIST SOUTHEASTERLY UPSLOPE FLOW CONTINUES AT 10 TO 15 KNOTS
ACROSS WESTERN KANSAS. CEILINGS AND VISIBILITIES AT GCK ARE ALSO
EXPECTED TO FALL BACK INTO THE LOW IFR/LIFR CATEGORY BY 08Z BASED
ON THE LATEST HRRR, RAP AND NAM. AN UPPER LEVEL DISTURBANCE WILL
CROSS THE CENTRAL PLAINS EARLY SUNDAY AND A SURFACE BOUNDARY,
LOCATED NEAR THE COLORADO BORDER AT 05Z, WILL INTO WESTERN KANSAS.
AS THE LOW LEVEL WINDS VEER TO THE SOUTHWEST THE VISIBILITIES AND
CEILINGS WILL IMPROVE. CONFIDENCE IS NOT HIGH ON TIMING BUT GIVEN
THE LATEST HRRR, RAP AND NAM WILL FAVOR IFR/MVFR AT GCK AND HYS
BETWEEN 12 AND 15Z SUNDAY. FOR DDC WILL KEEP IFR CONDITIONS UNTIL
LATE MORNING. VFR CONDITIONS ARE EXPECTED TO DEVELOP IN THE
AFTERNOON AS SUBSIDENCE DEVELOPS BEHIND THE UPPER LEVEL TROUGH.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 36 58 30 58 / 10 20 0 0
GCK 34 60 27 58 / 10 10 0 0
EHA 37 63 33 60 / 10 0 0 0
LBL 37 60 29 59 / 10 10 0 0
HYS 30 55 29 56 / 10 20 0 0
P28 36 57 33 58 / 10 20 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 9 AM CST SUNDAY FOR KSZ030-031-043>046-
063>066-076>081-086>090.
&&
$$
SYNOPSIS...BURGERT
SHORT TERM...JJOHNSON
LONG TERM...KRUSE
AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1000 PM MST SAT DEC 6 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 207 PM MST SAT DEC 6 2014
EARLY AFTERNOON WV IMAGERY AND RAP H5 ANALYSIS SHOW PROGRESSIVE
TROUGH-RIDGE TROUGH PATTERN ACROSS US WITH RIDGE CURRENTLY
EXTENDING FROM SOUTH CENTRAL CANADA ACROSS THE CENTRAL PLAINS. SW
FLOW IS IN PLACE FROM THE FOUR CORNERS REGION AND INTO WESTERN KS
WITH SHORTWAVE TROUGH MOVING OUT OF THE GREAT BASIN TOWARDS THE
CENTRAL ROCKIES. AT THE SURFACE LEE TROUGH IS IN PLACE OVER
EASTERN COLORADO WITH SOUTHERLY FLOW ACROSS OUR CWA.
AS SHORTWAVE TROUGH TRANSITIONS EASTWARD STATIONARY
FRONT/BAROCLINIC ZONE WITH SHIFT NORTH AND EAST ALLOWING FOR
SOUTHEAST MOISTURE RETURN INTO THE EASTERN HALF OF OUR CWA.
MIDLEVEL MOISTURE/UPPER LEVEL FORCING COULD ALLOW FOR A BRIEF
PERIOD OF LIGHT RAIN SHOWERS LATE TONIGHT...HOWEVER MODEL
SOUNDINGS INDICATE A SIGNIFICANT DRY LAYER WOULD LIKELY PREVENT
ANY ELEVATED PRECIPITATION FROM REACHING THE SURFACE.
MAIN CONCERN WILL BE POTENTIAL FOR DENSE FOG DEVELOPMENT AND
POTENTIAL FOR DRIZZLE ACROSS EASTERN CWA LATE TONIGHT THROUGH
SUNDAY MORNING. NAM/RAP SHOW WEAK SURFACE CONVERGENCE IN PROXIMITY
OF BAROCLINIC ZONE WHICH COULD PROVIDE ENOUGH LIFT WITHIN SHALLOW
SATURATED LAYER TO ALLOW FOR DRIZZLE DEVELOPMENT. THIS COULD BE
MORE OF A STRATUS/DRIZZLE EVENT...THOUGH CONSIDERING THE GOOD
MOISTURE RETURN LOWER VISIBILITIES ARE CERTAINLY POSSIBLE. HIGH
CLOUDS HAVE ALREADY BEEN HAVING AN IMPACT ON MIXING THIS
AFTERNOON...AND WITH THICKENING/LOWERING CLOUDS THOUGH THE NIGHT
(ALONG WITH TD VALUES INCREASING TO MID/UPPER 30S IN THE
EAST)...RADIATIONAL COOLING WILL BE LIMITED. NOT ONLY COULD THIS
LIMIT DENSE FOG DEVELOPMENT...BUT THIS MAKES FREEZING
FOG/FREEZING DRIZZLE UNLIKELY AT THIS POINT. AT THIS POINT HOLDING
OFF ON HIGHLIGHTS SEEMS THE BEST COURSE.
WITH SHIFT BACK TO SW FLOW AS SHORTWAVE RIDGING BUILDS BACK INTO
THE ROCKIES THERE SHOULD BE RAPID IMPROVEMENT IN CONDITIONS
SUNDAY.CLEARING SKIES AND WAA THROUGH THE AFTERNOON SHOULD ALLOW
HIGHS TO WARM TO AROUND 60F...THOUGH STRATUS MAY HOLD ON A LITTLE
LONGER IN OUR EASTERN CWA LIMITING DAYTIME MIXING AND KEEPING
HIGHS IN THE LOW TO MID 50S.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 207 PM MST SAT DEC 6 2014
UPPER FLOW WILL BE NORTHWEST SUNDAY NIGHT AHEAD OF A RIDGE THAT WILL
BUILD INTO THE ROCKIES AND PLAINS MONDAY AND TUESDAY. SURFACE HIGH
PRESSURE WILL RESIDE OVER THE PLAINS THROUGH THIS TIME.
DRY CONDITIONS WILL CONTINUE ACROSS THE FA THROUGH TUESDAY.
SUBSIDENCE AND OR A LACK OF SIGNIFICANT FORCING ALONG WITH A LACK OF
LAYER MEAN RH WILL PROVIDE SUPPORT FOR THE DRY CONDITIONS. POPS
WILL BE NIL FROM SUNDAY NIGHT THROUGH TUESDAY.
MIN TEMPERATURES SHOULD BE IN THE MID AND UPPER 20S SUNDAY AND
MONDAY NIGHTS. MAX TEMPERATURES SHOULD RISE TO THE MID 50S MONDAY
AND TUESDAY.
IN THE EXTENDED...(TUESDAY NIGHT THROUGH SATURDAY)...
THIS PART OF THE FORECAST IS ALSO DRY. A RIDGE WILL RESIDE OVER THE
PLAINS THROUGH THURSDAY AND THEN SHIFT EAST FRIDAY AND SATURDAY WITH
FLOW BECOMING SOUTHWEST. SURFACE HIGH PRESSURE WILL CONTINUE OVER
THE CENTRAL PLAINS THROUGH WEDNESDAY FOLLOWED BY A TROUGH IN
EASTERN COLORADO FROM THURSDAY THROUGH SATURDAY.
MAX TEMPERATURES WILL GENERALLY BE IN THE MID TO UPPER 50S WEDNESDAY
AND SATURDAY. MAX TEMPERATURES THURSDAY AND FRIDAY SHOULD WARM TO
THE UPPER 50S WITH LOWER 60S IN THE WESTERN FA. MIN TEMPERATURES
SHOULD COOL TO THE UPPER 20S AND LOWER 30S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1000 PM MST SAT DEC 6 2014
KGLD...SOUTH WIND AROUND 15KTS AT TAF ISSUANCE WILL VEER TO THE
SOUTH AND DECREASE TO 10KTS BY 08Z UNDER A VFR OVERCAST SKY. STRATUS/BR
MAY REACH THE TERMINAL FROM THE EAST/SOUTHEAST AROUND 08Z WITH
IFR CIGS EXPECTED FROM 08Z-11Z WITH WINDS FROM THE SOUTH AROUND
10KTS. AROUND 12Z WINDS VEER TO THE SOUTHWEST 5-10KTS PUSHING THE
STRATUS SLOWLY EAST ALLOWING FOR VFR CONDITIONS TO RETURN. WINDS
THEN GO WEST UNDER 10KTS AROUND 15Z THEN SHIFT TO THE NORTHWEST
12G20KT POSSIBLY A BIT HIGHER IN THE 18Z-22Z TIMEFRAME UNDER JUST
A FEW FAIR WEATHER CLOUDS. BY 23Z WINDS DISSIPATE TO 5KTS OR SO BY
23Z THEN BACK TO THE WEST AT SIMILAR SPEEDS AROUND 05Z.
KMCK...SOUTHEAST WIND NEAR 10KT AT TAF ISSUANCE UNDER A VFR
OVERCAST SKY. STRATUS/DRIZZLE/BR WITH IFR CONDITIONS AND POSSIBLY
VLIFR CONDITIONS WITH VIS 1/2SM IN FG/DZ REACH THE TERMINAL FROM
THE EAST AROUND 09Z AND CONTINUE THROUGH 17Z BEFORE WINDS VEER
AROUND TO THE NORTHWEST NEAR 10KTS IN THE 17Z-20Z TIMEFRAME. THIS
WILL SCOUR OUT THE STRATUS PRODUCING VFR CONDITIONS FROM 17Z
THROUGH THE REST OF THE TAF PERIOD.
IT SHOULD BE NOTED THAT IN THESE SCENARIOS THAT HIGH RESOLUTION
MODELS OCCASIONALLY DONT PUSH THE STRATUS FAR ENOUGH WEST...BY AT
LEAST ONE ROW OF COUNTIES. IF THIS VERIFIES STRATUS/BR (POSSIBLY
FG WITH VLIFR CONDITIONS) MAY TAKE UP TO AN ADDITIONAL 3 HOURS TO
MOVE OUT OF BOTH TERMINALS. WITH A THICK OVERCAST SKY HARD TO
WATCH STRATUS PROGRESSION ON SATELLITE IMAGERY SO WILL HAVE TO
WATCH METARS AND HOURLY MODEL UPDATES FROM THE RUC AND HRRR.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...FS
AVIATION...99
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
1139 PM CST SAT DEC 6 2014
.AVIATION...AMPLE MOISTURE REMAINS DESPITE THE FRONTAL PASSAGE.
WILL GO WITH PERSISTENCE AS UPSTREAM MVFR CIGS...AT OR BLO 2000FT
AND THE RUC FIELDS SUPPORT LITTLE CHANGE INTO SUNDAY. LOW SUN
ANGLES AND HIGH CLOUDS WILL MAKE FOR SLOW IMPROVEMENT BUT MVFR STRATOCU
CIGS SHOULD FINALLY DISPERSE BY MID-DAY SUNDAY WITH A CIRRUS DECK
ABOVE AND A CONTINUED NELY FLOW.
SWEENEY
&&
.PREV DISCUSSION... /ISSUED 936 PM CST SAT DEC 6 2014/
UPDATE...FORECAST LOOKS ON TRACK. NO UPDATE NEEDED.
MARCOTTE
PREV DISCUSSION... /ISSUED 536 PM CST SAT DEC 6 2014/
AVIATION...A CONCERN HAD BEEN THAT EXTENSIVE MOISTURE REMAINS IN
THE WAKE OF THE WEAK COLD FRONT AND THAT CONDITIONS COULD DETERIORATE.
THAT SAID, LOOKS LIKE A REINFORCING PUSH HAS SET UP ENOUGH COLD
AND DRY ADVECTION TO PROVIDE OVERALL IMPROVEMENT. IN THE NEAR
TERM, MVFR CIGS LOOK TO HANG IN UNTIL AFTER MIDNIGHT AT BOTH BPT
AND LCH. MVFR CIGS AT AEX SHOULD BECOME VFR LATER THIS EVENING AS
SKIES SCATTER OUT.
CURRENT VFR CONDTIONS AT THE ACADIANA AIRPORTS SHOW IMPROVEMENT
PER LATEST TIME-HEIGHT VERTICAL PROFILES. THAT SAID THERE IS AN
EXTENSIVE MVFR CIG FIELD UPSTREAM TO THE NORTH AND INBOUND PVA AT
THE BOUNDARY LAYER. THIS MOISTURE COULD BE JUST BELOW THE MODEL BOUNDARY.
LOOKS LIKE PRUDENCE DICTATES PERSISTENCE ON THE MVFR CIGS FOR LFT
AND ARA AT LEAST UNTIL THE PVA WANES AROUND AFTER MIDNIGHT.
SWEENEY
PREV DISCUSSION... /ISSUED 317 PM CST SAT DEC 6 2014/
DISCUSSION...
THIS AFTERNOON...LITTLE RAIN FELL ACROSS OUR LAND AREA...BUT THERE
IS A NARROW LINE OF SHOWERS IN THE COASTAL WATERS DUE TO A PRE-
FRONTAL TROUGH...WORKING ITS WAY FURTHER OFFSHORE. ALSO...DENSE
FOG HAS BEEN LINGERING OVER THE COASTAL WATERS...BUT IT IS
CLEARING WEST TO EAST THIS AFTERNOON...AND SHOULD BE DISSIPATED BY
THIS EVENING.
NO RAIN IS FORECAST OVER THE NEXT 7 DAYS...AND TEMPERATURES ARE
GENERALLY FORECAST TO BE NEAR NORMAL. SURFACE HIGH PRESSURE WILL
BE THE DOMINANT WEATHER PATTERN ACROSS OUR REGION...STARTING TO
OUR NORTH TONIGHT...AND SLOWLY WORKING ITS WAY TO OUR EAST BY THE
END OF NEXT WEEK.
15
&&
.PRELIMINARY POINT TEMPS/POPS...
KLCH 50 64 45 65 43 / 10 10 10 0 0
KBPT 51 65 45 65 44 / 10 10 10 0 0
KAEX 44 60 41 63 40 / 10 0 10 0 0
KLFT 49 63 44 65 43 / 10 10 10 0 0
&&
.LCH WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
TX...NONE.
GM...SMALL CRAFT EXERCISE CAUTION UNTIL 6 AM CST SUNDAY FOR THE
FOLLOWING ZONES: WATERS FROM INTRACOASTAL CITY TO CAMERON
LA FROM 20 TO 60 NM...WATERS FROM CAMERON LA TO HIGH ISLAND
TX FROM 20 TO 60 NM...WATERS FROM LOWER ATCHAFALAYA RIVER
TO INTRACOASTAL CITY LA FROM 20 TO 60 NM.
&&
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSLAKECHARLES
WWW.TWITTER.COM/NWSLAKECHARLES
WWW.YOUTUBE.COM/NWSLAKECHARLES
&&
$$
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1153 PM CST Sat Dec 6 2014
.UPDATE:
Issued at 918 PM CST Sat Dec 6 2014
Primary meteorological elements of interest tonight are sky cover
and temperatures. Complicated sky cover forecast as 11-3.9 micron
channel is showing advection of the low stratus deck slowly to the
WSW at around 15-20 knots. Concurrently...some thick cirrus is
moving ahead of the next shortwave and spilling over midlevel
ridge axis. Have updated grids to decrease the sky cover in the
near term where stratus deck is moving out of before ramping
opaque cloud cover back up due to the aforementioned thick cirrus
shield.
Other problem tonight as been temperatures as they have cooled off
quickly in areas which have scattered out due to loss of low
stratus deck. As a result...lowered temps in northeast Missouri
and southwest Illinois a bit through 6-9Z before leveling off as
cirrus overtakes the same region. Net result...not too much change
from previous forecast`s overnight minimums.
Gosselin
&&
.SHORT TERM: (Through Late Tonight)
Issued at 300 PM CST Sat Dec 6 2014
Low stratus located within the southern portion of a large high
pressure system continues to dominate the region at mid afternoon.
There has been a slow clearing trend to our north with the clearing
line located near the MO/IA border into northern IL. This high
pressure system will dominate tonight as it moves to the east with
low level flow gradually veering to easterly by mid evening and
then east-southeasterly overnight. Given the trends in the wind
field, there will probably be additional southward clearing into
the early evening then the northern edge will hold steady before
retreating back northwest overnight. The RAP H950 RH is the only
guidance that seems to have a decent handle on this evolution. The
abundance of clouds tonight would suggest MOS guidance is too low
on mins, with the coolest values expected across northeast MO and
west central IL.
Glass
.LONG TERM: (Sunday through Next Saturday)
Issued at 300 PM CST Sat Dec 6 2014
The high pressure system will continue to retreat on Sunday and
this will keep low clouds prevalent. Add in high clouds and it will
make for a mostly cloudy-cloudy day. There are some indications that
southern portions of the CWA could see some clearing from the
south of the low clouds, and hence warmer high temps are expected.
The next threat of precipitation will come Sunday night into
Monday morning. A short wave trof will dig into the mid-upper MS
valley. The large scale ascent associated with this wave along
increasing mid level moisture and low level warm advection should
be sufficient to generate some spotty/scattered precipitation
ahead of the attendant cold front. Temperature profiles indicate
the precipitation should be in the form of rain, with the highest
pops late Monday night across northeast MO and along and east of
the MS River on Monday morning. Monday should be milder with
decreasing clouds as first a prefrontal trof and then the cold
front then sweeps through the area. Another brief round of cold
air then dominates on Tuesday with expansive high pressure.
The upper air pattern will be in transition during the extended
period from Wednesday into next weekend. The eastern U.S. upper
trof/low will be progressive lifting northeast and eventually off
the Atlantic Seaboard. A northwest flow short wave in the wake of
the slowly retreating trof looks to impact our area sometime late
Wednesday into early Thursday, however present indications are any
precipitation threat should be confined to western MO. Heights
aloft then gradually rise in the wake of the shortwave trof and
high pressure departs, leading to southerly low level flow Friday
into the Saturday and a warming trend.
Glass
&&
.AVIATION: (For the 06z TAFs through 06z Sunday Night)
Issued at 1135 PM CST Sat Dec 6 2014
Difficult ceiling forecast for the rest of the night. The low MVFR
and IFR ceilings cleared rapidly from the northeast across the
area and now west central and most of southwest Illinois as well
as northeast Missouri and parts of east central Missouri are out
of the low stuff. Hard to see much detail from satellite pictures
at this time because of a blanket of rather dense cirrus clouds
which has moved over the area; but best guess from surface obs and
what I can see from satellite is that the clouds now stretch from
near KMBY to KSUS to near KMVN. the southwest progress of the
clearing appears to have slowed and it should stop over the next
couple of hours as low level flow turns more to the east and then
east-southeast. Should see some redevelopment in the clouds over
areas that are now clear as this occurs. Regardless, think MVFR
and IFR fog will likely prevail where clouds do not redevelop.
Where clouds redevelop toward morning, expect ceilings to persist
until late morning/early afternoon before scattering out. Fog
should dissipate within an hour or two after sunrise.
Specifics for KSTL:
MVFR ceilings have pushed just to the southwest of Lambert at this
hour. Expect the ceilings to stay to the southwest for a few hours
before moving back over the terminal before sunrise. Timing and
height of the clouds is uncertain at this time. Until then, expect
current 5SM fog to thicken a bit, perhaps down to 2SM...tho I feel
this is unlikely. Once clouds come back into the terminal, expect
ceilings to persist through the morning and scatter out during the
early afternoon due to daytime heating.
Carney
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1237 AM CST SUN DEC 7 2014
.UPDATE...
ISSUED AT 1236 AM CST SUN DEC 7 2014
MAIN CHANGE FOR THIS UPDATE WAS TO FINE TUNE THE LATE NIGHT/EARLY
MORNING PRECIP FORECAST.
A LIGHT BAND OF FREEZING RAIN CONTINUES TO TRACK EASTWARD ACROSS
MONTANA. GLASGOW MONTANA PICKED UP AROUND 0.01 INCHES OF FREEZING
RAIN AND REPORTED SLICK CONDITIONS. WHILE THIS BAND IS RATHER
SMALL AND PRODUCING VERY MINIMAL AMOUNTS...EVEN A LITTLE BIT OF
ICE CAN CAUSE PROBLEMS. LATEST RADAR TRENDS CONTINUE TO INDICATE
THAT THIS BAND OF FREEZING RAIN WILL MAKE IT INTO WESTERN NORTH
DAKOTA WITHIN THE NEXT HOUR. SHORT-TERM...HIGH RES MODELS HAVE A
POOR HANDLE ON THIS BAND...SO CONFIDENCE IN THE EVOLUTION OF THE
SHORT-TERM FORECAST IS RATHER LOW. THIS BAND OF PRECIP IS VERY
LIGHT AND NARROW AND COULD DISSIPATE AT ANY TIME AS THE MAIN
LOW PRESSURE CENTER IS STILL OUT IN CENTRAL MONTANA. BUT... FELT
IT BETTER TO BE SAFE THAN SORRY...SO KEPT THE SPECIAL WEATHER
STATEMENT GOING AND THE MENTION OF FREEZING RAIN IN THE FORECAST
THROUGH THE EARLY MORNING HOURS.
UPDATE ISSUED AT 905 PM CST SAT DEC 6 2014
LATEST REGIONAL RADAR IMAGERY SHOWS BAND OF LIGHT RAIN WORKING ITS
WAY FROM CENTRAL INTO EASTERN MONTANA. LATEST HIGH-RES GUIDANCE
CONTINUES TO HAVE A GOOD GRASP ON THE PRECIPITATION BEING
PRESENT...BUT OVER THE PAST FEW RUNS HAS HELD IT TOO FAR NORTH.
WITH THIS...HAVE SPREAD PRECIP CHANCES FURTHER SOUTH A BIT AND
HAVE INCREASED POPS SOME OVER MUCH OF FAR WESTERN NORTH DAKOTA AS
MODELS CONTINUE TO HOLD THIS TOGETHER AS IT PUSHES EAST. BY THE
TIME IT REACHES OUR AREA...IT SHOULD BE MAINLY LIGHT FREEZING
RAIN WITH THE COOLER SURFACE TEMPS. UPDATES HAVE BEEN SENT.
UPDATE ISSUED AT 620 PM CST SAT DEC 6 2014
SOME LIGHT RADAR RETURNS SHOWING UP OVER CENTRAL MONTANA WITH
LIGHT RAIN BEING REPORTED IN LEWISTOWN. WILL WATCH HOW THIS
EVOLVES THROUGH THE EVENING AS IT PUSHES EAST AS HIGH-RES MODELS
CONTINUE TO BRING SOME OF THIS PRECIPITATION INTO WESTERN NORTH
DAKOTA AFTER MIDNIGHT. FORECAST SOUNDINGS STILL SUGGEST THAT IF
ANY PRECIPITATION DOES DEVELOP IT WILL BE FREEZING RAIN. CURRENT
FORECAST REFLECTS THIS WELL. ONLY CHANGE THAT WAS MADE FOR EARLY
EVENING UPDATE WAS TO INCREASE CLOUD COVER TO ACCOUNT FOR HIGH
CLOUDS COVERING MUCH OF THE AREA.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 333 PM CST SAT DEC 6 2014
THE MAIN FORECAST ISSUE IN THE SHORT TERM PERIOD WILL BE POSSIBLE
FREEZING PRECIPITATION TONIGHT AND SUNDAY.
CURRENTLY A SHORTWAVE TROUGH IS LOCATED OVER EASTERN WASHINGTON. THE
WAVE WILL TRACK ALONG THE INTERNATIONAL BORDER OVERNIGHT AND DEVELOP
A SURFACE LOW IN THE LEE OF THE ROCKIES. THE SURFACE/UPPER LEVEL LOW
IS PROGGED TO BE OVER NORTHEAST MT/SOUTH CENTRAL SK BY 12 UTC
SUNDAY. WARM ADVECTION AHEAD OF THE LOW WILL RESULT IN WARM
TEMPERATURES ALOFT ENCOMPASSING ALL OF WESTERN AND CENTRAL NORTH
DAKOTA TONIGHT. THUS THE POTENTIAL FOR FREEZING PRECIPITATION
THROUGH SUNDAY AFTERNOON.
THE LATEST 20 UTC RAP DEPICTS A BAND OF LIGHT REFLECTIVITIES MOVING
INTO WESTERN NORTH DAKOTA AROUND 08 UTC SUNDAY. HOWEVER...ANY
MEASURABLE PRECIPITATION REMAINS CONFINED TO THE FAR NORTHWEST
CORNER OF NORTH DAKOTA. THE RAP MAINTAINS THE LIGHT REFLECTIVITIES
AS THEY CROSS THE CWA BUT KEEPS MAINLY TRACE AMOUNTS...AND MAINLY
CONFINED TO THE FAR NORTHERN TIER COUNTIES. THE GFS/EC/GEM ALL
BRING VERY LIGHT QPF INTO THE FAR NORTHWEST THROUGH 12 UTC. THE
EC/GEM ALSO TRACK SOME TRACE AMOUNTS ALONG THE NORTHERN TIER
COUNTIES THROUGH THE MORNING. THE GFS IS FARTHER SOUTH AND IS ON
THE SOUTHERN SIDE OF THE ENVELOPE OF DETERMINISTIC SOLUTIONS. THUS
HAVE KEPT BEST CHANCE FOR QPF IN THE FAR NORTHWEST 06-12 UTC
SUNDAY AND ACROSS THE FAR NORTHERN TIER COUNTIES 12-18 UTC SUNDAY.
WILL STILL HAVE A MENTION OF SOME FREEZING RAIN SOUTHWEST AND
SOUTH CENTRAL (MAINLY ALONG AND NORTH OF I-94) BUT WITH NO
SIGNIFICANT ACCUMULATIONS. EVEN ACROSS THE NORTH...DETERMINISTIC
MODEL QPF REMAINS AT OR BELOW A HUNDREDTH OF AN INCH. ONLY A
LITTLE FREEZING RAIN CAN CAUSE SIGNIFICANT TRAVEL ISSUES. BUT WITH
LOW MODEL QPF...WILL HOLD OFF ON ANY HIGHLIGHTS AT THIS TIME. WE
WILL STILL HAVE TIME TO WATCH THINGS DEVELOP ACROSS NORTHEAST
MONTANA AND SOUTHERN SASKATCHEWAN THIS EVENING AND OVERNIGHT.
COULD STILL SEE A VERY LIGHT MIX OVER THE NORTH CENTRAL MONDAY
AFTERNOON. BUT WESTERN NORTH DAKOTA WILL BE ON THE BACK SIDE OF THE
MID LEVEL TROUGH WITH COLD ADVECTION TRACKING SOUTHEAST ACROSS THE
CWA DURING THE AFTERNOON. THUS THE WEST WILL QUICKLY TRANSITION TO
SNOW AND THE SOUTH CENTRAL SHOULD WARM UP ENOUGH TO SEE ALL RAIN
WITH A QUICK CHANGE TO SNOW AS THE COLD ADVECTION ARRIVES.
IT WILL ALSO BECOME BREEZY TO WINDY SUNDAY AFTERNOON FROM WEST TO
EAST BEHIND THE TRACK OF THE LOW. STRONGEST WINDS 20-30 MPH WITH
GUSTS TO 35 MPH WILL SPREAD FROM THE SOUTHWEST SUNDAY AFTERNOON INTO
THE CENTRAL LATE AFTERNOON TO EARLY EVENING. HIGHS SUNDAY WILL
LIKELY BE REACHED IN THE MORNING NORTH TO EARLY AFTERNOON SOUTH WITH
TEMPERATURES FALLING MID TO LATE AFTERNOON EVERYWHERE.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 333 PM CST SAT DEC 6 2014
POST FRONTAL NORTHWEST WINDS OF 20 TO 30 MPH ALONG WITH ISOLATED TO
SCATTERED SNOW SHOWERS WILL DOMINATE SUNDAY NIGHT. THE ENTIRE SYSTEM
DEPARTS CENTRAL NORTH DAKOTA BY 12Z MONDAY WITH COLDER AIR REMAINING
IN PLACE FOR THE MORNING FOLLOWED BY WARM AIR ADVECTION MONDAY
AFTERNOON ESPECIALLY IN THE WEST. A PROGRESSIVE PATTERN CONTINUES
WITH A TRANSITORY RIDGE SHIFTING THROUGH MONDAY NIGHT FOLLOWED BY A
DRY SHORTWAVE TROUGH PASSING THROUGH TUESDAY. THEREAFTER...UPPER
RIDGING DOMINATES AND SHIFTS EAST BY MIDWEEK ALLOWING A SOUTHWEST
FLOW TO RETURN. HOWEVER NOTHING FORESEEN IN THE SOUTHWEST FLOW IN
TERMS OF SIGNIFICANT SHORTWAVES AT LEAST THROUGH SATURDAY PER
GFS/GEM GLOBAL/SUPERBLEND. HOWEVER THE LATEST ECMWF PUSHES A FAST
MOVING SHORTWAVE AND CONSEQUENTLY LIGHT PRECIPITATION/FAVORING RAIN
SHOWERS AT THIS POINT...ACROSS THE NORTH THURSDAY. HIGH TEMPERATURES
WILL WARM TO BETWEEN 35F AND 45F WEDNESDAY THROUGH FRIDAY...THEN A
BIT COOLER FOR SATURDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1236 AM CST SUN DEC 7 2014
VFR CONDITIONS ARE EXPECTED THROUGH THE OVERNIGHT HOURS. -FZRA
MAY MOVE INTO WESTERN NORTH DAKOTA AFTER 07Z AND PUSH EAST THROUGH
THE MORNING HOURS. THE BEST CHANCE OF FREEZING RAIN IS AT KISN
BETWEEN 08Z AND 09Z. LEFT OUT OTHER TERMINALS FOR NOW GIVEN THE LOW
COVERAGE...BUT WILL MONITOR THROUGH THE EVENING. WINDS WILL
SHIFT FROM THE WEST/NORTHWEST AND AREAS OF PRECIPITATION WILL
DEVELOP...MAINLY OVER THE NORTHWEST LATER THIS MORNING. -RA/-FZRA
WILL BE POSSIBLE....WITH A TRANSITION TOWARDS -SN AS COOLER AIR
MOVES IN FROM NORTHWEST TO SOUTHEAST. CIGS WILL DIMINISH TO MVFR
LEVELS FROM NORTHWEST TO SOUTHEAST STARTING LATE MORNING AND
CONTINUING THROUGH THE AFTERNOON.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AJ
SHORT TERM...TWH
LONG TERM...KS
AVIATION...AJ
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
1233 AM EST SUN DEC 7 2014
.SYNOPSIS...
LOW PRESSURE WAVE PASSES WITH COLDER AIR IN ITS WAKE TONIGHT.
HIGH PRESSURE SUNDAY. UPPER TROUGH MONDAY NIGHT/TUESDAY. COLDER
AIR TUESDAY NIGHT INTO WEDNESDAY.
&&
.NEAR TERM /THROUGH TODAY/...
10 PM UPDATE. NO SIGNIFICANT CHANGES.
PREVIOUS DISCUSSION...
AS OF 18Z THE FRONT HAS CLEARED CRW AND CKB WITH SURFACE LOW E OF
EKN. FRONT WILL CLEAR THE MOUNTAINS BY 21Z. AS THE FRONT
CROSSES...TEMPERATURE FALLS OF 7 TO 10 DEGREES CAN BE EXPECTED
WITH GRADUALLY LOWERING TEMPS THEREAFTER THROUGH THE EVENING. LOW
CIGS AND VSBY IN POST FRONTAL DZ CAN BE EXPECTED THRU THE
REMAINDER OF THE AFTERNOON...ALONG WITH GUSTY NW WINDS. WILL WATCH
-RA TO FILL BACK IN LATER THIS AFTERNOON AS THE UPPER LEVEL TROF
CROSSES. AREA WILL BEGIN TO DRY OUT WITH PASSAGE OF THE UPPER
LEVEL TROF...SAVE FOR SOME DZ HANGING ON ACROSS THE MOUNTAINS THIS
EVENING. ELECTED TO KEEP POSSIBILITY OF IT ENDING AS A LITTLE FRZ
DZ BUT NOT EXPECTING ANY IMPACTS.
WHAT WILL NOT CLEAR OUT THIS EVENING IS THE LOW STRATUS.
HOWEVER...DO EXPECT BASES TO LIFT A BIT TONIGHT. THINK SE OH WILL
SCT OUT DURING THE PREDAWN. HOWEVER...DEVELOPING SUBSIDENCE
INVERSION BENEATH THIS LINGERING MOISTURE WILL MAKE IT VERY
DIFFICULT FOR STRATUS TO BREAK UP E OF THE OH RIVER OVERNIGHT. WITH WEAK
CAA BENEATH THE INVERSION AND LOW LEVEL WINDS BECOMING MORE
NE...FELT IT NECESSARY TO HOLD THE STRATUS IN ALONG THE
CLIMATOLOGICAL FAVORED AREAS IN THIS SETUP....IE THE C LOWLANDS
AND COAL FIELDS THRU THE MORNING HOURS. CLOUDS WILL GRADUALLY SCT
OUT FROM NE TO SW...WITH AREAS ALONG AND S OF I64 CORRIDOR THE
LAST TO LOSE THE STRATUS...POSSIBLY HOLDING ON UNTIL LATE
AFTERNOON.
FOR TEMPS...USED A BLEND OF LAMP AND HRRR FOR TEMPS TONIGHT. FOR
SUNDAY...USED MET AS A BASE WHICH BETTER REFLECTED EXPECTED COOLER
READINGS ALONG AND ESPECIALLY S OF I64 CORRIDOR DUE TO CLOUDS.
FURTHER N...FELT LOCAL MOS WAS THE WAY TO GO WHERE READINGS SHOULD
REACH INTO THE MID OR UPPER 40S.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY/...
STRONG MID LEVEL RIDGING AND HIGH PRESSURE INFLUENCES FROM EASTERN
CANADA DOMINATE SUNDAY...BUT SUNSHINE STILL LIMITED TO THE MORNING
HOURS WITH CIRRUS AHEAD OF THE UPPER LEVEL TROUGH DIGGING IN OVER
THE WESTERN GREAT LAKES. MODELS NOW SETTLING ON THE TROUGH AXIS
HOLDING THE DEVELOPING COASTAL SYSTEM OFFSHORE AND MAINLY AWAY FROM
OUR EASTERN MOST RIDGES...BUT WILL STILL ENTERTAIN SOME LOW END POPS
FOR THE FAR EASTERN PORTIONS OF RAND/POCA COUNTIES. SOME ICING IS
POSSIBLE IN THE SOUTHEAST UPSLOPE AREAS.
HAVE THE TRANSITION TO SNOW FOR THE LOWLAND UPSLOPE AREAS FROM RAIN
TO SNOW A BIT SLOWER...AND JUST BEGINNING BY THE END OF THE SHORT
TERM FORECAST AT 00Z WEDNESDAY. 925MB TEMPERATURES GO BELOW 0C JUST
AFTER 21Z TUESDAY FOR THE MOUNTAINS...MAKING THE 18Z TO 00Z PERIOD
THE RAIN/SNOW TRANSITION TIMES FOR THE MOUNTAINOUS AREAS. LOWLANDS
WILL TRANSITION TO SNOW LIKELY IN THE BEGINNING FEW HOURS OF THE
LONG TERM.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
USED A BLEND OF THE GFS...GEFS MEAN...ECMWF...ECMWF MEAN...AND
CONTINUITY WITH THE PREVIOUS FORECAST. THIS WOULD HAVE WRAP AROUND
MOISTURE OVER THE REGION FOR TUESDAY NIGHT INTO WEDNESDAY. 850 MB
TEMPERATURES ARE MARGINAL FOR UPSLOPE SNOW...SO COULD SEE DRIZZLE
INSTEAD OF SNOW IN MANY AREAS. A HIGH PRESSURE SYSTEM THEN MOVES IN
FOR THE END OF THE WORK WEEK AND INTO THE WEEKEND...ALLOWING
TEMPERATURES TO MODERATE SOME.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
MVFR CIGS STILL IN PLACE ACROSS MOST OF FORECAST AREA...WITH IFR
AT BKW. EXPECT CONDITIONS TO STAY FAIRLY SIMILAR FOR THE NEXT
SEVERAL HOURS BEFORE GRADUAL IMPROVEMENT BEGINS. AS DRY AIR MOVES
IN FROM THE N...CLOUDS WILL SCATTER OUT LATER TODAY WITH VFR
EXPECTED AT ALL TAF SITES BY MID TO LATE MORNING. CURRENT
NORTHERLY WINDS WILL TURN MORE EASTERLY BY TONIGHT.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z MONDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATE SCENARIOS: TIMING OF IMPROVEMENTS MAY VARY.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE SUN 12/07/14
UTC 1HRLY 06 07 08 09 10 11 12 13 14 15 16 17
EST 1HRLY 01 02 03 04 05 06 07 08 09 10 11 12
CRW CONSISTENCY H H H H H H H H H H M M
HTS CONSISTENCY H H H H H H H M M M M M
BKW CONSISTENCY H H H H H M H H M M M M
EKN CONSISTENCY M H H H H H M M M M H H
PKB CONSISTENCY H H H M M M M M M M M M
CKB CONSISTENCY H H H H H M M M M M M M
AFTER 06Z MONDAY...
IFR POSSIBLE IN RAIN/SNOW MONDAY NIGHT INTO WEDNESDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...RPY/JMV/30/26
NEAR TERM...JMV/30
SHORT TERM...26
LONG TERM...RPY
AVIATION...MZ
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
1145 PM CST SAT DEC 6 2014
.AVIATION...
LIFR CONDITIONS SHOULD CONTINUE AT KCDS MOST IF THE NIGHT...THEN
SLOWLY IMPROVE SUNDAY MORNING. KLBB AND KPVW ARE LIKELY TO
EXPERIENCE A PERIOD OF MVFR AND POSSIBLY IFR CONDITIONS DUE TO
LOW STRATUS AND FOG...WITH SOME UNCERTAINTY WITH TIMING THE RETURN
TO VFR CONDITIONS LATE IN THE MORNING OR AROUND MIDDAY SUNDAY. IN
ADDITION...-SHRA WILL BE POSSIBLE AT ALL TERMINALS...MORE LIKELY
AT KLBB BETWEEN ROUGHLY 08 UTC AND 16 UTC. SURFACE WINDS WILL
REMAIN LIGHT THROUGH THE PERIOD AND SLOWLY SWING AROUND FROM E-SE
TO S-SW.
&&
.PREV DISCUSSION... /ISSUED 1045 PM CST SAT DEC 6 2014/
UPDATE...
QUICK UPDATE TO ADD A DENSE FOG ADVISORY TO THE FAR SOUTHEAST TX
PANHANDLE AND THE ROLLING PLAINS. THICK FOG HAS MADE IT TO MEMPHIS
AND DICKENS AND SHORT-TERM GUIDANCE SHOWS IT SLOWLY EXPANDING
WESTWARD THROUGH EARLY SUNDAY MORNING. IN FACT THE ADVISORY MAY
NEED EVENTUALLY NEED TO BE EXPANDED FARTHER WEST IF THE HRRR IS
CORRECT.
PREV DISCUSSION... /ISSUED 542 PM CST SAT DEC 6 2014/
AVIATION...
ALL TERMINALS SHOULD BE VFR AT 00 UTC. HOWEVER...LOW STRATUS AND
FOG ARE PRODUCING IFR CONDITIONS JUST TO THE EAST OF KCDS. THIS
AREA IS EXPECTED TO EXPAND WESTWARD THIS EVENING...DROPPING KCDS
OUT OF VFR BY 01 UTC OR SO AND LIKELY IMPACTING KLBB AND KPVW
AFTER ABOUT 08 UTC. CEILING AND VSBY REDUCTIONS MAY PERSIST
THROUGH EARLY SUNDAY MORNING. IN ADDITION...AS A STORM SYSTEM
PASSES ACROSS THE REGION...SCATTERED -SHRA ARE POSSIBLE AT ALL
TERMINALS BETWEEN ABOUT 06 UTC AND 16 UTC...WITH KLBB MOST LIKELY
TO SEE A RAIN SHOWER. SURFACE WINDS WILL REMAIN LIGHT THROUGH THE
PERIOD AND SLOWLY SWING AROUND FROM A EASTERLY TO SOUTHERLY FETCH.
PREV DISCUSSION... /ISSUED 343 PM CST SAT DEC 6 2014/
SHORT TERM...
THE BACK EDGE OF A SURFACE HIGH WAS SLOWLY EXITING THE WESTERN SOUTH
PLAINS THIS AFTERNOON AHEAD OF STEADY PRESSURE FALLS IN NEW MEXICO.
THESE PRESSURE DEFICITS WERE IN RESPONSE TO A TROUGH APPROACHING
FROM THE DESERT SOUTHWEST WHICH SHOULD REACH THE FORECAST AREA BY
SUNDAY MORNING. SATELLITE PRESENTATION OF THIS WAVE APPEARS
RESPECTABLE...HOWEVER REGIONAL METARS AND RADAR MOSAICS IN AZ AND
NM ARE NOT VERY INSPIRING FOR MEASURABLE PRECIP CHANCES IN THE NEXT
24 HOURS. WORSE...THIS WAVE IS SHOWN TO DAMPEN AS IT LIFTS NORTHEAST.
DESPITE THIS DECAYING TREND...A GRADUAL UPTICK IN MOIST ISENTROPIC
LIFT WILL DEVELOP TONIGHT AND PULL SLIGHTLY HIGHER THETA-E AIR
NORTHWARD. AT THE SAME TIME HOWEVER THIS MOIST LAYER WILL BE ON THE
THIN SIDE.
EVEN WITH TOP-DOWN MOISTENING SHOWN BY THE MODELS BY SUN MORNING...
A NOTABLE DRY LAYER CENTERED AROUND 750MB MAY ROB MUCH OF THIS
MOISTURE AND YIELD ONLY SPRINKLES. CHOSE TO KEEP 20 POPS ACROSS THE
SOUTHERN HALF OF THE CWA FROM 12-18Z WHERE A BRIEF WINDOW FOR SPOTTY
LIGHT SHOWERS LOOKS MOST FAVORABLE...BUT PRIOR TO THIS POPS WERE
SCALED BACK CONSIDERABLY IN COVERAGE DUE TO DELAYED MOISTENING.
OTHERWISE...THE AXIS OF THIS POSITIVELY TILTED TROUGH WILL BE
DEPARTING THE CWA THROUGH THE AFTERNOON AHEAD OF AMPLE MID-LEVEL
DRYING. TEMPS WERE NUDGED UP OVERNIGHT IN LIGHT OF INCREASING CLOUDS
AND LL MOISTURE. ON A RELATED NOTE...THE ADVECTION FOG THREAT
OVERNIGHT APPEARS LESS IN COVERAGE AND DURATION...BUT REMAINS VALID.
LONG TERM...
IN THE EXTENDED...A HIGH AMPLITUDE RIDGE ALONG THE WEST COAST WILL
EXTEND CLEAR INTO ALASKA TO WEST OF NOME AS LOW NEAR 47N150W REMAINS
A SEMI-PERMANENT FEATURE FOR THE NEXT WEEK. WAVES OF ENERGY WILL
SHOOT ACROSS THE PACIFIC NORTHWEST THOUGH A NOTABLE WEAKNESS IN THE
RIDGE WILL APPROACH OUR AREA LATE TUESDAY. THIS SYSTEM WILL BE
QUITE WEAK AND ONLY SLOWLY DRIFT EAST OF US BY THURSDAY AS A
RESPECTABLE AMPLITUDE TROUGH MOVES ACROSS THE DESERT SOUTHWEST FOR
NEXT WEEKEND.
MODELS CONTINUE TO ADVERTISE RAIN CHANCES THAT ARE HIGHER THAN WHAT
WOULD BE EXPECTED GIVEN THE WEAK NATURE OF THE SYSTEM INTO TUESDAY
AND WEDNESDAY WITH DRY CONDITIONS EXPECTED THROUGH THE END OF THE
WORK WEEK. OVERALL...A FAIRLY TRANQUIL WEEK IS AHEAD WITH TEMPS
GENERALLY ABOVE SEASONAL NORMS. MANY QUESTIONS REMAIN REGARDING
NEXT WEEKEND/S SYSTEM WHETHER IT MAY BE A RAIN OR A WIND EVENT.
CLIMATOLOGY WOULD TEND TO SUGGEST WIND.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 37 58 32 61 34 / 10 10 0 0 0
TULIA 39 58 32 62 34 / 10 10 0 0 0
PLAINVIEW 39 58 33 62 34 / 10 10 0 0 0
LEVELLAND 39 58 34 62 37 / 20 20 0 0 0
LUBBOCK 41 58 34 62 37 / 10 20 0 0 0
DENVER CITY 37 55 34 61 37 / 20 20 0 0 0
BROWNFIELD 40 56 35 61 37 / 10 20 0 0 0
CHILDRESS 41 56 36 65 38 / 10 10 0 0 0
SPUR 42 56 37 64 38 / 10 20 0 0 0
ASPERMONT 43 55 39 64 39 / 10 20 10 0 0
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 9 AM CST SUNDAY FOR THE FOLLOWING
ZONES: TXZ024>026-030>032-036>038-043-044.
&&
$$
33
AREA FORECAST DISCUSSION...UPDATED
NWS LUBBOCK TX
1045 PM CST SAT DEC 6 2014
.UPDATE...
QUICK UPDATE TO ADD A DENSE FOG ADVISORY TO THE FAR SOUTHEAST TX
PANHANDLE AND THE ROLLING PLAINS. THICK FOG HAS MADE IT TO MEMPHIS
AND DICKENS AND SHORT-TERM GUIDANCE SHOWS IT SLOWLY EXPANDING
WESTWARD THROUGH EARLY SUNDAY MORNING. IN FACT THE ADVISORY MAY
NEED EVENTUALLY NEED TO BE EXPANDED FARTHER WEST IF THE HRRR IS
CORRECT.
&&
.PREV DISCUSSION... /ISSUED 542 PM CST SAT DEC 6 2014/
AVIATION...
ALL TERMINALS SHOULD BE VFR AT 00 UTC. HOWEVER...LOW STRATUS AND
FOG ARE PRODUCING IFR CONDITIONS JUST TO THE EAST OF KCDS. THIS
AREA IS EXPECTED TO EXPAND WESTWARD THIS EVENING...DROPPING KCDS
OUT OF VFR BY 01 UTC OR SO AND LIKELY IMPACTING KLBB AND KPVW
AFTER ABOUT 08 UTC. CEILING AND VSBY REDUCTIONS MAY PERSIST
THROUGH EARLY SUNDAY MORNING. IN ADDITION...AS A STORM SYSTEM
PASSES ACROSS THE REGION...SCATTERED -SHRA ARE POSSIBLE AT ALL
TERMINALS BETWEEN ABOUT 06 UTC AND 16 UTC...WITH KLBB MOST LIKELY
TO SEE A RAIN SHOWER. SURFACE WINDS WILL REMAIN LIGHT THROUGH THE
PERIOD AND SLOWLY SWING AROUND FROM A EASTERLY TO SOUTHERLY FETCH.
PREV DISCUSSION... /ISSUED 343 PM CST SAT DEC 6 2014/
SHORT TERM...
THE BACK EDGE OF A SURFACE HIGH WAS SLOWLY EXITING THE WESTERN SOUTH
PLAINS THIS AFTERNOON AHEAD OF STEADY PRESSURE FALLS IN NEW MEXICO.
THESE PRESSURE DEFICITS WERE IN RESPONSE TO A TROUGH APPROACHING
FROM THE DESERT SOUTHWEST WHICH SHOULD REACH THE FORECAST AREA BY
SUNDAY MORNING. SATELLITE PRESENTATION OF THIS WAVE APPEARS
RESPECTABLE...HOWEVER REGIONAL METARS AND RADAR MOSAICS IN AZ AND
NM ARE NOT VERY INSPIRING FOR MEASURABLE PRECIP CHANCES IN THE NEXT
24 HOURS. WORSE...THIS WAVE IS SHOWN TO DAMPEN AS IT LIFTS NORTHEAST.
DESPITE THIS DECAYING TREND...A GRADUAL UPTICK IN MOIST ISENTROPIC
LIFT WILL DEVELOP TONIGHT AND PULL SLIGHTLY HIGHER THETA-E AIR
NORTHWARD. AT THE SAME TIME HOWEVER THIS MOIST LAYER WILL BE ON THE
THIN SIDE.
EVEN WITH TOP-DOWN MOISTENING SHOWN BY THE MODELS BY SUN MORNING...
A NOTABLE DRY LAYER CENTERED AROUND 750MB MAY ROB MUCH OF THIS
MOISTURE AND YIELD ONLY SPRINKLES. CHOSE TO KEEP 20 POPS ACROSS THE
SOUTHERN HALF OF THE CWA FROM 12-18Z WHERE A BRIEF WINDOW FOR SPOTTY
LIGHT SHOWERS LOOKS MOST FAVORABLE...BUT PRIOR TO THIS POPS WERE
SCALED BACK CONSIDERABLY IN COVERAGE DUE TO DELAYED MOISTENING.
OTHERWISE...THE AXIS OF THIS POSITIVELY TILTED TROUGH WILL BE
DEPARTING THE CWA THROUGH THE AFTERNOON AHEAD OF AMPLE MID-LEVEL
DRYING. TEMPS WERE NUDGED UP OVERNIGHT IN LIGHT OF INCREASING CLOUDS
AND LL MOISTURE. ON A RELATED NOTE...THE ADVECTION FOG THREAT
OVERNIGHT APPEARS LESS IN COVERAGE AND DURATION...BUT REMAINS VALID.
LONG TERM...
IN THE EXTENDED...A HIGH AMPLITUDE RIDGE ALONG THE WEST COAST WILL
EXTEND CLEAR INTO ALASKA TO WEST OF NOME AS LOW NEAR 47N150W REMAINS
A SEMI-PERMANENT FEATURE FOR THE NEXT WEEK. WAVES OF ENERGY WILL
SHOOT ACROSS THE PACIFIC NORTHWEST THOUGH A NOTABLE WEAKNESS IN THE
RIDGE WILL APPROACH OUR AREA LATE TUESDAY. THIS SYSTEM WILL BE
QUITE WEAK AND ONLY SLOWLY DRIFT EAST OF US BY THURSDAY AS A
RESPECTABLE AMPLITUDE TROUGH MOVES ACROSS THE DESERT SOUTHWEST FOR
NEXT WEEKEND.
MODELS CONTINUE TO ADVERTISE RAIN CHANCES THAT ARE HIGHER THAN WHAT
WOULD BE EXPECTED GIVEN THE WEAK NATURE OF THE SYSTEM INTO TUESDAY
AND WEDNESDAY WITH DRY CONDITIONS EXPECTED THROUGH THE END OF THE
WORK WEEK. OVERALL...A FAIRLY TRANQUIL WEEK IS AHEAD WITH TEMPS
GENERALLY ABOVE SEASONAL NORMS. MANY QUESTIONS REMAIN REGARDING
NEXT WEEKEND/S SYSTEM WHETHER IT MAY BE A RAIN OR A WIND EVENT.
CLIMATOLOGY WOULD TEND TO SUGGEST WIND.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 37 58 32 61 34 / 10 10 0 0 0
TULIA 39 58 32 62 34 / 10 10 0 0 0
PLAINVIEW 39 58 33 62 34 / 10 10 0 0 0
LEVELLAND 39 58 34 62 37 / 20 20 0 0 0
LUBBOCK 41 58 34 62 37 / 10 20 0 0 0
DENVER CITY 37 55 34 61 37 / 20 20 0 0 0
BROWNFIELD 40 56 35 61 37 / 10 20 0 0 0
CHILDRESS 41 56 36 65 38 / 10 10 0 0 0
SPUR 42 56 37 64 38 / 10 20 0 0 0
ASPERMONT 43 55 39 64 39 / 10 20 10 0 0
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 9 AM CST SUNDAY FOR THE FOLLOWING
ZONES: TXZ024>026-030>032-036>038-043-044.
&&
$$
33/23
AREA FORECAST DISCUSSION
NWS EUREKA CA
453 AM PST SUN DEC 7 2014
.SYNOPSIS...A LOW PRESSURE SYSTEM WILL APPROACH THE COAST TODAY
BRINGING LIGHT TO MODERATE RAIN BY THIS EVENING. A CHANCE OF RAIN
WILL PERSIST MONDAY THROUGH TUESDAY. A STRONGER STORM WILL ARRIVE
AROUND MID WEEK AND PROMISES TO BRING HEAVY RAIN WEDNESDAY NIGHT
INTO THURSDAY.
&&
.DISCUSSION...SATELLITE IMAGERY SHOWED A SHORTWAVE TROUGH JUST
OUTSIDE 130W EARLY THIS MORNING. ALL THE MODELS HAVE SLOWED DOWN
THE ARRIVAL OF THE RAIN WITH THIS TROUGH TIL LATE THIS AFTERNOON
INTO THIS EVENING. THE 6Z NAM12 AND 6Z GFS SPED UP THE ARRIVAL
SOME...HOWEVER IT STILL LOOKS LIKE MOST OF THE PRECIP WILL ARRIVE
AFTER ABOUT 5 PM. THE HRRR MODEL DOES SHOW SOME RETURNS SPIKING UP
OVER THE INTERIOR THIS AFTERNOON...BUT HAS THE BRUNT OF THE
REFLECTIVITIES STILL OFFSHORE OVER THE COASTAL WATERS AROUND 4PM.
SOUTHEASTERLY AND EASTERLY WINDS WILL RAMP UP THIS AFTERNOON AS
THE TROUGH LINE APPROACHES THE COAST. WINDS WERE ALREADY A BIT
BREEZY OVER THE RIDGES AND GUSTS TO 20-30 MPH DOWN TO MEAN SEA
LEVEL CAN BE EXPECTED. THE WEAKENING SHORTWAVE WILL MOVE ACROSS
THE AREA THIS EVENING AND PROBABLY PRODUCE A TENTH TO A QUARTER OF
AN INCH OF RAIN. ALSO THE MODELS NO LONGER INDICATE THAT THE
TROUGH WILL ACQUIRE A NEGATIVE TILT. THE GFS STILL SHOWS WEAK
INSTABILITY OVER THE FAR WESTERN PERIPHERY OF MARINE ZONE 475
TODAY...SO LEFT THE SLIGHT CHANCE OF THUNDERSTORMS IN THE GRIDS
THERE.
THE MODELS WERE IN SLIGHTLY BETTER AGREEMENT ON HOW QUICKLY THE
RAIN WILL END OR DECREASE TONIGHT. THE GFS, ECMWF AND NAM12 DO
SHOW LINGERING LIGHT PRECIP IN MENDO COUNTY AND IN EASTERN
TRINITY...SO MAINTAINED SLIGHTLY HIGHER PRECIP CHANCES THERE TIL
EARLY MONDAY MORNING. MODELS DO SHOW ANOTHER SHORTWAVE TROUGH
MOVING TOWARD THE AREA ON MONDAY WHICH MAY BRING MORE SHOWERS BY
MON NIGHT.
MOIST SOUTHWESTERLY FLOW WILL INCREASE ON TUE AS ANOTHER SHORTWAVE
TROUGH MOVES TOWARD THE AREA. RAIN CHANCES APPEAR TO INCREASE ON
TUE...HOWEVER THE MODELS WERE NOT IN VERY GOOD AGREEMENT ON THE
PRECIP. BEST CHANCES AND HIGHEST AMOUNTS LOOK TO BE IN DEL NORTE
COUNTY. CONFIDENCE IS NOT HIGH AS THE MODELS WERE NOT IN GREAT
AGREEMENT AND KEEP CHANGING AROUND FROM ONE RUN TO THE NEXT. SO
DID NOT MAKE TOO MANY ADJUSTMENTS FOR TUE.
A RAINY AND WINDY STORM SYSTEM REMAINS ON TRACK TO IMPACT
NORTHWEST CALIFORNIA STARTING ON WEDNESDAY...WITH WET AND
UNSETTLED WEATHER CONDITIONS CONTINUING THROUGH THE REMAINDER OF
THE WEEK. THE 0Z RUNS OF THE GFS AND ECMWF WERE GOOD AGREEMENT
BRINGING RAIN INTO THE COAST BY THE AFTERNOON ON WEDNESDAY. RAIN
WILL OVERSPREAD THE AREA OVERNIGHT WED INTO THURSDAY. AN UPPER
TROUGH WILL MOVE TOWARD THE COAST THURSDAY INTO FRIDAY AND EXPECT
SHOWERS TO CONTINUE. AMPLE DEEP LAYER MOISTURE CONTINUES TO BE
INDICATED WITH THIS SYSTEM WITH HIGH PWAT VALUES. THERE WILL
LIKELY BE PERIODS OF MODERATE TO HEAVY RAIN. ON FRIDAY...THE GFS
HAS SHOWERS CONTINUING OVER THE AREA WITH GOOD INSTABILITY
PRESENT. HAVE KEPT ANY MENTION OF THUNDERSTORMS OUT OF THE
FORECAST AT THIS POINT. SNOW LEVELS WILL START OFF NEAR 7K FEET ON
WEDNESDAY AND GRADUALLY FALL TO BETWEEN 4KFT FEET BY FRIDAY IF THE
GFS IS CORRECT. THE LAST COUPLE RUNS OF THE GFS AND ECMWF HAVE
BEEN IN GOOD AGREEMENT SHOWING THE TROUGH MOVING THROUGH FRI
NIGHT. ISOLATED SHOWERS MAY STILL DEVELOP IN THE COOLER AIR AND NW
FLOW BEHIND THE UPPER TROUGH ON SAT...SO LEFT A SLIGHT CHANCE OF
PRECIP IN THE FORECAST. IF THE MODELS ARE CORRECT...TEMPERATURES
WILL COOL DOWN FRI INTO SAT AS THE TROUGH EXITS TO THE EAST.
A COASTAL FLOOD ADVISORY HAS BEEN ISSUED FROM 10 AM TO 2 PM TODAY
FOR MINOR FLOODING OF LOW LYING AREAS AROUND HUMBOLDT BAY DUE TO
A HIGH ASTRONOMICAL TIDE. IMPACTS ARE EXPECTED TO BE MARGINAL AS
THE TIDE IS FORECAST TO BE 7.76 FT WITH AN ANOMALY AROUND 1 FT.
THE CRITERIA FOR AN ADVISORY IS 8.8 FT. HIGH TIDE WILL OCCUR AT
11:30 AM TODAY WITH WATER LEVELS APPROACHING 8.8 FT. WE ANTICIPATE
THE FLOODING THREAT TO DIMINISH NEXT WEEK BUT A HIGH TIDAL ANOMALY
ON MONDAY COULD RESULT IN MORE COASTAL FLOODING.
&&
.AVIATION...LOW CLOUDS AND FOG ACROSS THE INTERIOR VALLEYS WILL
SCOUR OUT TODAY AS STRONG SOUTHERLY FLOW DEVELOPS AHEAD OF A COLD
FRONT. OTHERWISE CONDITIONS ARE EXPECTED TO REMAIN VFR THROUGH MUCH
OF THE DAY. THE COLD FRONT WILL BRING PERIODS OF IFR DURING HEAVY
RAIN BANDS. OTHERWISE LOOK FOR LOWER CLOUD DECKS THROUGH THE DAY AND
STRONG SOUTHERLY WINDS ALONG THE COAST. BFG
&&
.MARINE...A SERIES OF FRONTS WILL SWEEP OVER THE COASTAL WATERS THIS
WEEK WITH STRONG TO GALE FORCE SOUTHERLY WINDS PRECEDING. STEEP
SOUTHERLY WAVES WILL ACCOMPANY THESE INCREASING WINDS. THE FIRST
FRONT WILL CAUSE BUILDING CONDITIONS TODAY INTO EARLY MONDAY THEN
SUBSIDE SLIGHTLY ON MONDAY. CONDITIONS WILL AGAIN DETERIORATE
MIDWEEK AS ANOTHER STRONG FRONT APPROACHES THE WATERS. THE MODELS
SEEM TO BE IN GOOD AGREEMENT WITH THIS PATTERN, SO HAVE FOLLOW MODEL
GUIDANCE FOR THE FORECAST.
AN ACTIVE STORM TRACK IS ENTRENCHED OVER THE NORTHERN PACIFIC WITH A
CORE OF WINDS POINTING AT THE WEST COAST OF THE UNITED STATES. THIS
IS CAUSING LARGE WAVES WHICH ARE PROPAGATING TOWARD THE COAST. WAVES
MODELS ARE SHOWING FORERUNNERS ARRIVING ON TUESDAY THEN BUILDING
QUICKLY INTO WEDNESDAY. THIS WESTERLY SWELL COULD REACH AS HIGH AS
18 FT AT 14 SECONDS ON WEDNESDAY. COMBINE THIS WITH GALES OUT OF THE
SOUTH AND THE ASSOCIATED STEEP WAVES AND COMBINED SEAS MAY REACH AS
HIGH AS 20 TO 24 FEET. LATE WEEK, MODELS ARE NOT IN GOOD AGREEMENT
MAKING FOR A LOW CONFIDENCE FORECAST. OVERALL IT WILL BE A ROUGH
WEEK FOR THE COASTAL WATERS. BFG
&&
.EKA WATCHES/WARNINGS/ADVISORIES...
CA...
COASTAL FLOOD ADVISORY FROM 10 AM THIS MORNING TO 2 PM PST THIS
AFTERNOON FOR CAZ001.
NORTHWEST CALIFORNIA COASTAL WATERS...
COASTAL FLOOD ADVISORY FROM 10 AM THIS MORNING TO 2 PM PST THIS
AFTERNOON FOR PZZ410.
SMALL CRAFT ADVISORY FROM 9 AM THIS MORNING TO 3 AM PST MONDAY
FOR PZZ455.
SMALL CRAFT ADVISORY FROM 3 PM THIS AFTERNOON TO 3 AM PST MONDAY
FOR PZZ450.
SMALL CRAFT ADVISORY UNTIL 9 AM PST THIS MORNING FOR PZZ470-475.
GALE WARNING FROM 9 AM THIS MORNING TO 9 PM PST THIS EVENING FOR
PZZ470.
GALE WARNING FROM 9 AM THIS MORNING TO 3 PM PST THIS AFTERNOON
FOR PZZ475.
&&
$$
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AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
556 AM CST SUN DEC 7 2014
.SHORT TERM...
427 AM CST
A HIGH AMPLITUDE...PROGRESSIVE UPPER LEVEL PATTERN WILL BRING VERY
CHANGEABLE WEATHER TO THE REGION FOR THE NEXT SEVERAL DAYS...THOUGH
THE MAIN CONCERN WILL BE A WINTRY MIXED PCPN EVENT FOR SUNDAY NIGHT
INTO MONDAY MORNING.
THROUGH MONDAY NIGHT...
FOR THE REMAINDER OF THE NIGHT AND INTO SUNDAY MORNING...CONDITIONS
WILL REMAIN QUIET WITH INCREASING HIGH CLOUD COVER WHICH WILL LIMIT
ANY FURTHER RADIATIVE COOLING AND TEMPERATURES ACROSS THE REGION
SHOULD BOTTOM OUT IN THE LOWER TO MIDDLE 20S...EXCEPT FOR DOWNTOWN
CHICAGO WHICH WILL ONLY DROP TO AROUND 30F. THE REMAINDER OF SUNDAY
SHOULD BE RELATIVELY INNOCUOUS WITH CONTINUED INCREASING MID AND
HIGH LEVEL CLOUD COVER. AS THE CENTER OF A LARGE AREA OF HIGH
PRESSURE SHIFTS FROM THE UPPER GREAT LAKES TO ERN CANADA...A LOW
PRESSURE SYSTEM WILL MOVE OUT OF THE SRN CANADIAN ROCKIES...DRAGGING
A WEAK COLD FRONT INTO THE PLAINS. LOW LEVEL FLOW WILL BECOME MORE
SELY AHEAD OF THE APPROACHING SYSTEM...THOUGH WITH HIGH PRESSURE
RIDGING STILL NOSING SOUTHWEST INTO THE LOWER MISSISSIPPI
VALLEY...EVEN AS TEMPERATURES RISE INTO UPPER 30S...DEWPOINTS WILL
REMAIN RELATIVELY LOW...REMAINING IN THE LOW 20S.
AS THE SYSTEM APPROACHES THE REGION...CONCERNS WILL BECOME PCPN TYPE
AND AMOUNT WITH THE SYSTEM. PREVIOUS MODEL RUNS HAD MAINTAINED A
RELATIVELY DRY ENVIRONMENT AS THE GULF OF MEXICO REMAIN CUT OFF FROM
THE NRN STREAM SYSTEM AND ANY LOW LEVEL MOISTURE TRANSPORT WILL HAVE
TO TAKE A LONG PATH AROUND THE PERIPHERY OF THE SFC RIDGE BEFORE
REACHING INTO THE MIDDLE MISSISSIPPI VALLEY. HOWEVER...THE LATEST
MODEL RUNS ARE INDICATING MORE MOISTURE AVAILABLE TO THE SYSTEM WITH
FORECAST PWATS AROUND 3/4 INCH AND MANY MODELS ARE PAINTING MORE QPF
THAN PREVIOUS RUNS. HAVE SOME CONCERN THAT THE MODELS ARE OVER
FORECASTING MOISTURE CONTENT AND QPF...SO HAVE GONE WITH A MORE
CONSERVATIVE APPROACH TO QPF AMOUNTS THAT WHAT MANY OF THE MODELS
WOULD SUGGEST. HOWEVER...STILL FEEL THAT THERE WILL BE ENOUGH DEEP
LAYER MOISTURE TO PRODUCE MEASURABLE PCPN ACROSS THE REGION. THE
REAL CONCERN WILL BE PCPN TYPE WITH AMOUNTS MORE OF A SECONDARY
CONCERN. THIS IS LARGELY BECAUSE THE GUIDANCE IS INDICATING AN
INTRUSION OF WARM AIR ABOVE A NEARLY SATURATED...BUT BELOW FREEZING
SFC LAYER. THE LATEST RUNS OF THE LOCAL WRFARW...WHICH WAS LARGELY
FOLLOWED FOR THE FINER SCALE DETAILS OF THE PCPN TYPE TREND
INDICATES A RATHER THICK WARM LAYER WITH MAX TEMPS WITHING THE WARM
LAYER OF +3 TO +5C ABOVE A SURFACE BASED INVERSION WITH SFC
TEMPERATURES ARND 30F BY THE TIME THE LEADING EDGE OF THE PCPN MOVES
INTO THE FAR NWRN PORTIONS OF THE CWA. THE LATEST GUIDANCE SUGGESTS
THAT PCPN COULD MOVE INTO THE NWRN PORTIONS OF THE CWA BY ARND
06Z...AND WITH SFC TEMPS OF 30F...BELOW THE DEEP WARM LAYER...PCPN
SHOULD LARGELY BE FREEZING RAIN. THE LEADING EDGE OF THE FREEZING
RAIN SHOULD STEADILY CROSS THE CWA...REACHING THE CHICAGO METRO AREA
DURG THE PREDAWN HOURS. A RATHER STRONG MID LEVEL SHORTWAVE...WITH
700MB OMEGA MAX MOVING ACROSS THE AREA...THERE WILL LIKELY BE A
PERIOD OF SLEET MIXING IN WITH THE FREEZING RAIN DURG THE MORNING
HOURS. PCPN TYPE BECOME A LITTLE MORE COMPLICATED BY LATE MORNING
AND INTO THE AFTERNOON HOURS. MID LEVEL DRY AIR SHOULD MOVE IN
RELATIVELY QUICKLY AS THE HEAVIEST BAND OF PCPN TRACKS FROM WEST TO
EAST ACROSS THE AREA. THE MID LEVEL DRYING COULD OCCUR BEHIND THE
PASSAGE OF THE SFC COLD FRONT. HOWEVER...SINCE THIS SYSTEM IS A
MODIFIED PACIFIC SYSTEM...TEMPERATURES SHOULD NOT DROP OFF QUICKLY
OR SIGNIFICANTLY FOLLOWING THE FROPA...BUT THERE COULD BE A QUICK
BURST OF MODERATE SNOW FOR A SHORT PERIOD WITH THE FROPA AS THE MID
LEVEL WARM LAYER ERODES AND THE ENTIRE COLUMN DROPS BELOW FREEZING.
LATEST THINKING WITH THAT THE ENTIRE CWA SHOULD SEE A LEAST A LIGHT
GLAZING OF FREEZING RAIN...WITH PERHAPS A LIGHT ICE ACCUMULATION
OVER THE NORTHERN PORTIONS OF THE CWA...WHERE QPF AND FORCING WILL
BE STRONGER. ALSO...IT LOOKS LIKE THE ROCKFORD AREA SHOULD HAVE THE
BETTER OPPORTUNITY FOR ACCUMULATING SNOWFALL AS THE THE BEST TIMING
FOR A BURST OF HEAVIER SNOW WILL OCCUR EARLIER IN THE DAY...BEFORE
SFC TEMPS HAVE A CHANCE TO RISE ABOVE FREEZING. BY THE TIME THAT
THE COLD FRONT REACHES THE ERN PORTIONS OF THE CWA...SFC
TEMPERATURES MAY WARM ABOVE FREEZING AND THE CHANCES FOR MUCH
MEASURABLE SNOWFALL WILL BE LOWER....WITH THE FAR SOUTHERN AND SERN
PORTION OF THE CWA...LOCATIONS GENERALLY SOUTH OF THE KANKAKEE RIVER
POSSIBLY ONLY SEEING SOME LIGHT FREEZING RAIN BEFORE BRIEFLY
CHANGING OVER TO SNOW AND THEN EVENTUALLY CHANGING OVER TO ALL RAIN
BY LATE MONDAY MORNING. SO...THE LATEST FORECAST UPDATE WILL
INCLUDE MEASURABLE SNOW NORTH OF THE IL/KANKAKEE RIVERS...WITH THE
I39 CORRIDOR SEEING AS MUCH A 1 INCH OF TOTAL ACCUMULATION...BEFORE
THE WARMER AIR MOVES IN AND MELTS ANY ACCUMULATING SNOW. LOCATIONS
NORTH OF THE RIVERS AND EAST OF I-39 SHOULD ONLY SEE AROUND A HALF
INCH SO SO OF SNOW. THE GREATEST CONCERN WILL BE IMPACTS ON TRAVEL
AS THE FREEZING/FROZEN PCPN WILL BE MOVING ACROSS THE AREA AROUND
THE MORNING RUSH HOURS...AND WITH EVEN LIGHT FREEZING RAIN...THERE
COULD BE TRAVEL DIFFICULTIES. BY LATE MORNING...SFC TEMPS SHOULD
RISE ABOVE FREEZING AND WITH SFC FLOW ONLY VEERING FROM SWLY TO WLY
WITH THE FROPA...LITTLE ACTUAL COOLING IS EXPECTED WITH THE FROPA
AND TEMPERATURES COULD REACH INTO THE UPPER 30S TO AROUND 40F BY
LATE MONDAY AFTERNOON. THE MORE SIGNIFICANT COLD ADVECTION WILL NOT
BEGIN UNTIL THE LATE EVENING HOURS AS THE NEXT SFC HIGH BUILDS
ACROSS THE NRN PLAINS...SETTING UP NWLY FLOW ACROSS THE REGION AND
BY TUESDAY MORNING...TEMPERATURES SHOULD DROP INTO THE MIDDLE TO
UPPER 20S.
KREIN
&&
.LONG TERM...
427 AM CST
TUESDAY THROUGH NEXT SATURDAY...
THE EXTENDED FORECAST PERIOD LOOK TO BE GENERALLY QUIET ACROSS THE
MIDWEST AS DEEP LOW PRESSURE DEVELOPS OF THE MID ATLANTIC
COAST...SLOWING THE PROGRESSION OF THE SFC HIGH ACROSS THE AREA.
THE LATEST LONGER RANGE GUIDANCE SUGGESTS THAT THE CENTER OF THE
HIGH WILL BE SHUNTED INTO SERN CANADA BY THE DEEP LOW OFF THE EAST
COAST...WITH RIDGING EXTENDING THROUGH THE GREAT LAKES AND MIDDLE
MISSISSIPPI VALLEY THROUGH MUCH OF THE WEEK. TEMPERATURES SHOULD
GENERALLY BE SEASONABLE WITH HIGHS IN THE LOWER TO MIDDLE 30S
THROUGH THURSDAY WITH OVERNIGHT LOWS IN THE LOWER TO MIDDLE 20S.
PREVAILING HIGH PRESSURE WILL HELP KEEP THE REGION DRY AND NO
ADDITIONAL PCPN IS LIKELY THROUGH MUCH OF THE WEEK. THE MODELS
CONTINUE TO ADVERTISE A SIGNIFICANT WARMING TREND BY THE END OF THE
WEEK. THE MAIN IDEA IS THAT THE DEEP COASTAL LOW AND THE PARENT
UPPER LOW WILL REMAIN NEARLY STATIONARY OVER THE MID ATLANTIC
COAST...WHILE STRONG UPPER RIDGING BUILDS OVER THE WRN CONUS BY
FRIDAY...THE UPPER RIDGE IS EXPECTED TO BUILD OVER THE UPPER
MISSISSIPPI VALLEY AND ACROSS THE WRN GREAT LAKES BY NEXT SATURDAY.
THE LONGER RANGE TEMPERATURE GUIDANCE IS SUGGESTING THAT
TEMPERATURES COULD REACH INTO THE LOWER TO MIDDLE 40S BY FRIDAY AND
MIDDLE TO UPPER 40S FOR SATURDAY. HOWEVER...LONGER RANGE
TEMPERATURE GUIDANCE TENDS TO TREND A LITTLE CLOSER TO CLIMATOLOGY
TOWARD THE END OF THE FORECAST PERIOD...SO THE GOING FORECAST OF
MIDDLE TO UPPER 40S FOR NEXT SATURDAY COULD BE ON THE CONSERVATIVE
SIDE...AND WITH THE TYPE OF UPPER LEVEL PATTERN EVOLVING...THERE IS
THE POTENTIAL THAT TEMPERATURES FOR FRIDAY AND SATURDAY COULD VERY
WELL APPROACH OR EXCEED THE 50F MARK.
KREIN
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 12Z...
* SOUTHEAST WINDS AROUND 10 KT TODAY.
* BAND OF MIXED PRECIPITATION EXPECTED MONDAY MORNING. MAY START
AS -FZRA THEN TURN TO SHORT PERIOD OF SLEET/SNOW. IFR CIGS/VSBY
POSSIBLE FOR A FEW HOUR PERIOD.
MDB
//DISCUSSION...UPDATED 12Z...
HIGH PRESSURE RIDGING IS ACROSS THE AREA THIS MORNING BUT WILL BE
SHIFTING TO THE EAST. THIS WILL RESULT IN STEADY SOUTHEAST WINDS
THROUGH THE DAY WITH VFR CONDITIONS. LOW PRESSURE WILL MOVE ACROSS
THE AREA MONDAY MORNING BRINGING A PERIOD OF MIXED PRECIPITATION
WITH IT. A FEW HOUR PERIOD IS EXPECTED TO BEGIN TOWARD 09Z OUT
NEAR RFD AND TOWARD 11Z IN THE CHICAGO AREA. THE DETAILS REMAIN IN
FLUX BUT THE LATEST THINKING IS THAT PRECIPITATION WILL START OUT
AS A SHORT PERIOD OF FREEZING RAIN THEN TRANSITION TO A MIX OF
SLEET AND SNOW FOR A 1-3 HOUR PERIOD. FORCING IS STRONG FOR A
SHORT TIME SO IT IS POSSIBLE THAT A PERIOD OF MODERATE SNOW OCCURS
LEADING TO SOME SLUSHY ACCUMULATION. PRECIPITATION WILL INITIALLY
BE FIGHTING A LAYER OF DRY AIR SO ONSET COULD BE DELAYED AND THIS
MAY ALSO AFFECT THE PROGRESSION OF PRECIP TYPES. PRECIP INTENSITY
WILL QUICKLY DIMINISH MID TO LATE MORNING MONDAY WITH LIGHT RAIN
OR DRIZZLE POSSIBLE AS TEMPERATURES WARM ABOVE FREEZING. A PERIOD
OF IFR CIGS IS EXPECTED PROVIDED DECENT PRECIP OCCURS AND IFR VSBY
WOULD BE LIKELY IF A SHORT PERIOD OF MAINLY SNOW CAN OCCUR. BE
SURE TO CHECK BACK FOR FURTHER UPDATES...
MDB
//ORD AND MDW CONFIDENCE...UPDATED 12Z...
* HIGH CONFIDENCE IN WIND TRENDS.
* MEDIUM-HIGH CONFIDENCE IN A BAND OF MIXED PRECIPITATION
OCCURRING MONDAY MORNING. MEDIUM CONFIDENCE IN PROGRESSION OF
PRECIP TYPE AND TIMING.
MDB
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
MONDAY NIGHT...VFR. NW WINDS.
TUESDAY...VFR. NW WINDS BECOMING N.
WEDNESDAY...VFR. N WINDS.
THURSDAY...VFR. S WINDS.
FRIDAY...VFR. S WINDS.
SATURDAY...VFR. S WINDS.
MDB
&&
.MARINE...
251 AM CST
HIGH PRESSURE IS CENTERED OVER EASTERN ONTARIO EARLY THIS MORNING
WITH A RIDGE AXIS EXTENDING ACROSS LAKE MICHIGAN. THIS HAS ALLOWED
WINDS TO EASE AND TURN EAST TO NORTHEAST AND WILL ALLOW FOR A SHIFT
TO SOUTHEAST THROUGH THE MORNING. WILL ALLOW THE SMALL CRAFT
ADVISORY TO EXPIRE AS WINDS CONTINUE TO EASE ALLOWING WAVES TO BE ON
A DOWNWARD TREND. WILL CONTINUE WITH A 3-5 OCCASIONAL 7 FT FORECAST.
LOW PRESSURE IS OVER SOUTHERN SASKATCHEWAN AND EASTERN MONTANA AND
WILL BE MOVING EAST ALONG THE CANADIAN BORDER REACHING LAKE SUPERIOR
BY MIDDAY MONDAY. WITH THE HIGH PRESSURE RATHER STRONG THE PRESSURE
GRADIENT BETWEEN IT AND THE LOW WILL BE TIGHTENING THROUGH THE DAY
DESPITE THE LOW NOT BEING TERRIBLY DEEP. AS A RESULT WIND SPEEDS
WILL STEADILY INCREASE TO ABOUT 30 KT ACROSS MOST OF THE LAKE THIS
EVENING WITH SOME 35 KT GALE FORCE GUSTS POSSIBLE ACROSS CENTRAL AND
NORTHERN SECTIONS OVERNIGHT INTO EARLY MONDAY MORNING AS WINDS TURN
MORE SOUTHERLY. WILL ISSUE A SMALL CRAFT ADVISORY FOR MOST OF THE
ILLINOIS NEARSHORE FROM EARLY THIS EVENING THROUGH LATE MONDAY
MORNING AS WINDS AND WAVES COME UP. WINDS WILL THEN TURN
SOUTHWESTERLY MONDAY AFTERNOON AS THE LOW TRACKS TO THE EAST WITH
A SHIFT TO NORTHWEST MONDAY EVENING. COLDER AIR WILL SPREAD IN ON
A FAIRLY STRONG HIGH THAT WILL MOVE INTO THE MID AND UPPER
MISSISSIPPI RIVER VALLEY TUESDAY WHICH WILL ALLOW NORTHWEST WINDS
TO INCREASE EARLY TUESDAY MORNING AND TURN NORTH THROUGH THE DAY.
SPEEDS WILL THEN EASE INTO TUESDAY NIGHT AS THE HIGH MOVES CLOSER
THEN SPREADS ACROSS THE LAKE LATER WEDNESDAY. THE HIGH WILL BE
SLOW TO SHIFT TO THE EAST BUT WINDS WILL TURN WESTERLY AS IT DOES
THURSDAY THEN SOUTHWESTERLY THURSDAY NIGHT. STEADY SOUTHWEST WINDS
ARE THEN EXPECTED INTO THE WEEKEND AS THE HIGH SLOWLY MOVES OFF TO
THE EAST.
MDB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...LMZ740-LMZ741...6 PM SUNDAY TO 10 AM
MONDAY.
&&
$$
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FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.YOUTUBE.COM/NWSCHICAGO
[top]
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
554 AM CST Sun Dec 7 2014
.SHORT TERM...(Today)
ISSUED AT 331 AM CST SUN DEC 7 2014
Clouds have cleared out to the south tonight for now, but they are
lingering very close-by. Satellite images already confirm increasing
high clouds from the west. The HRRR is advertising a return of low
clouds from the east-southeast across the eastern half of the area
between 15z/9am and 18z/Noon today, but that seems a bit aggressive
based on the current progression of clouds across Indiana and the
expected wind patterns this morning. Have increased clouds from the
west based on satellite and model consensus, but only trended minor
increases in clouds across the east during the day for now. Will
monitor the movement of low clouds toward our eastern counties for
potential sky cover updates in the short term.
Northeast flow early this morning is expected to evolve to east and
then southeast this afternoon, as high pressure centered over the
Lake Michigan departs farther east across the Great Lakes. The onset
of southeast winds will increase the potential return of low clouds
currently lingering across southern IL.
Temperatures today will only climb about 12-13F above morning lows
due to increasing clouds, with highs topping out in the upper 30s
to low 40s.
&&
.LONG TERM...(Tonight through Saturday)
ISSUED AT 331 AM CST SUN DEC 7 2014
High pressure continues to build into the region, although clouds
continue to dominate the Midwest. Plenty of moisture on sat imagery
obscuring the llvl clouds underneath. Clearing in patches certainly
not anticipated for long as llvl moisture remains trapped by
continuing strong inversion over the area. The dry air aloft is not
coincident with enough turbulence to break up the inversion and
erode the higher RH at roughly 925 mb. This dry air will also be
the first issue for eroding the approaching precip late Sun night
and into Monday. Models maintaining consistency with the last two
runs and continuity with one another with regards to approach and
qpf after midnight tonight and into Monday. A quick front moving
through the area bringing precip after midnight and through the day
Monday so far looks like mostly rain, though the nrn tier of the
state may see a bit more of a rain/snow/wintry mix. Concern remains
whether or not the models are too quick to overcome the dry air
aloft or whether or not the precip may be delayed slightly.
Beyond Monday`s cold front, temps cool briefly, then moderate back
into the 40s for highs through the end of the week. 00z GFS
agreeing with yesterdays 00z ECMWF and backing down from the precip
Wed/Thursday, instead dominating the sfc map with high pressure.
Pops mid week have been removed. Deepening low over the
northeast/east coast causing a bit of a back up across the CONUS as
it is slow to move and the models having some issue with pushing the
new wave inland on the Pacific coast and managing the ridging in the
middle. Seems from Friday and into the weekend the forecast becomes
a bit more problematic in the details as the models work out a
pattern shift again.
&&
.AVIATION...(For the 12Z TAFS through 12Z Monday morning)
ISSUED AT 554 AM CST SUN DEC 7 2014
High pressure centered over lower Michigan and extending SW into
IL will slide east today. That movement will cause our surface
winds to shift from NE to SE by this afternoon, while increasing
to 10-14kt. High clouds will blanket the entire state today, with
low clouds lurking just south of our forecast area already at
12z/6am. As winds shift to SE, that cloud mass will eventually
gain momentum toward the terminal sites. HRRR indicates that SPI
and DEC will have the higher potential of seeing a return of MVFR
clouds after 22z/4pm, with the clouds eventually advancing all the
way north to PIA/BMI/CMI during the evening. The initial push of
moisture may have breaks in the ceiling per the latest HRRR, so we
delayed the persistent low clouds until later evening when light
rain will begin to develop from NW to SE ahead of an approaching
warm front and low pressure system. While any light rain could
change to freezing rain late in this TAF period, we did not
include FZRA with this issuance. We only mentioned VCSH after
midnight for now.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Shimon
LONG TERM...HJS
AVIATION...Shimon
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
430 AM CST SUN DEC 7 2014
.SHORT TERM...
427 AM CST
A HIGH AMPLITUDE...PROGRESSIVE UPPER LEVEL PATTERN WILL BRING VERY
CHANGEABLE WEATHER TO THE REGION FOR THE NEXT SEVERAL DAYS...THOUGH
THE MAIN CONCERN WILL BE A WINTRY MIXED PCPN EVENT FOR SUNDAY NIGHT
INTO MONDAY MORNING.
THROUGH MONDAY NIGHT...
FOR THE REMAINDER OF THE NIGHT AND INTO SUNDAY MORNING...CONDITIONS
WILL REMAIN QUIET WITH INCREASING HIGH CLOUD COVER WHICH WILL LIMIT
ANY FURTHER RADIATIVE COOLING AND TEMPERATURES ACROSS THE REGION
SHOULD BOTTOM OUT IN THE LOWER TO MIDDLE 20S...EXCEPT FOR DOWNTOWN
CHICAGO WHICH WILL ONLY DROP TO AROUND 30F. THE REMAINDER OF SUNDAY
SHOULD BE RELATIVELY INNOCUOUS WITH CONTINUED INCREASING MID AND
HIGH LEVEL CLOUD COVER. AS THE CENTER OF A LARGE AREA OF HIGH
PRESSURE SHIFTS FROM THE UPPER GREAT LAKES TO ERN CANADA...A LOW
PRESSURE SYSTEM WILL MOVE OUT OF THE SRN CANADIAN ROCKIES...DRAGGING
A WEAK COLD FRONT INTO THE PLAINS. LOW LEVEL FLOW WILL BECOME MORE
SELY AHEAD OF THE APPROACHING SYSTEM...THOUGH WITH HIGH PRESSURE
RIDGING STILL NOSING SOUTHWEST INTO THE LOWER MISSISSIPPI
VALLEY...EVEN AS TEMPERATURES RISE INTO UPPER 30S...DEWPOINTS WILL
REMAIN RELATIVELY LOW...REMAINING IN THE LOW 20S.
AS THE SYSTEM APPROACHES THE REGION...CONCERNS WILL BECOME PCPN TYPE
AND AMOUNT WITH THE SYSTEM. PREVIOUS MODEL RUNS HAD MAINTAINED A
RELATIVELY DRY ENVIRONMENT AS THE GULF OF MEXICO REMAIN CUT OFF FROM
THE NRN STREAM SYSTEM AND ANY LOW LEVEL MOISTURE TRANSPORT WILL HAVE
TO TAKE A LONG PATH AROUND THE PERIPHERY OF THE SFC RIDGE BEFORE
REACHING INTO THE MIDDLE MISSISSIPPI VALLEY. HOWEVER...THE LATEST
MODEL RUNS ARE INDICATING MORE MOISTURE AVAILABLE TO THE SYSTEM WITH
FORECAST PWATS AROUND 3/4 INCH AND MANY MODELS ARE PAINTING MORE QPF
THAN PREVIOUS RUNS. HAVE SOME CONCERN THAT THE MODELS ARE OVER
FORECASTING MOISTURE CONTENT AND QPF...SO HAVE GONE WITH A MORE
CONSERVATIVE APPROACH TO QPF AMOUNTS THAT WHAT MANY OF THE MODELS
WOULD SUGGEST. HOWEVER...STILL FEEL THAT THERE WILL BE ENOUGH DEEP
LAYER MOISTURE TO PRODUCE MEASURABLE PCPN ACROSS THE REGION. THE
REAL CONCERN WILL BE PCPN TYPE WITH AMOUNTS MORE OF A SECONDARY
CONCERN. THIS IS LARGELY BECAUSE THE GUIDANCE IS INDICATING AN
INTRUSION OF WARM AIR ABOVE A NEARLY SATURATED...BUT BELOW FREEZING
SFC LAYER. THE LATEST RUNS OF THE LOCAL WRFARW...WHICH WAS LARGELY
FOLLOWED FOR THE FINER SCALE DETAILS OF THE PCPN TYPE TREND
INDICATES A RATHER THICK WARM LAYER WITH MAX TEMPS WITHING THE WARM
LAYER OF +3 TO +5C ABOVE A SURFACE BASED INVERSION WITH SFC
TEMPERATURES ARND 30F BY THE TIME THE LEADING EDGE OF THE PCPN MOVES
INTO THE FAR NWRN PORTIONS OF THE CWA. THE LATEST GUIDANCE SUGGESTS
THAT PCPN COULD MOVE INTO THE NWRN PORTIONS OF THE CWA BY ARND
06Z...AND WITH SFC TEMPS OF 30F...BELOW THE DEEP WARM LAYER...PCPN
SHOULD LARGELY BE FREEZING RAIN. THE LEADING EDGE OF THE FREEZING
RAIN SHOULD STEADILY CROSS THE CWA...REACHING THE CHICAGO METRO AREA
DURG THE PREDAWN HOURS. A RATHER STRONG MID LEVEL SHORTWAVE...WITH
700MB OMEGA MAX MOVING ACROSS THE AREA...THERE WILL LIKELY BE A
PERIOD OF SLEET MIXING IN WITH THE FREEZING RAIN DURG THE MORNING
HOURS. PCPN TYPE BECOME A LITTLE MORE COMPLICATED BY LATE MORNING
AND INTO THE AFTERNOON HOURS. MID LEVEL DRY AIR SHOULD MOVE IN
RELATIVELY QUICKLY AS THE HEAVIEST BAND OF PCPN TRACKS FROM WEST TO
EAST ACROSS THE AREA. THE MID LEVEL DRYING COULD OCCUR BEHIND THE
PASSAGE OF THE SFC COLD FRONT. HOWEVER...SINCE THIS SYSTEM IS A
MODIFIED PACIFIC SYSTEM...TEMPERATURES SHOULD NOT DROP OFF QUICKLY
OR SIGNIFICANTLY FOLLOWING THE FROPA...BUT THERE COULD BE A QUICK
BURST OF MODERATE SNOW FOR A SHORT PERIOD WITH THE FROPA AS THE MID
LEVEL WARM LAYER ERODES AND THE ENTIRE COLUMN DROPS BELOW FREEZING.
LATEST THINKING WITH THAT THE ENTIRE CWA SHOULD SEE A LEAST A LIGHT
GLAZING OF FREEZING RAIN...WITH PERHAPS A LIGHT ICE ACCUMULATION
OVER THE NORTHERN PORTIONS OF THE CWA...WHERE QPF AND FORCING WILL
BE STRONGER. ALSO...IT LOOKS LIKE THE ROCKFORD AREA SHOULD HAVE THE
BETTER OPPORTUNITY FOR ACCUMULATING SNOWFALL AS THE THE BEST TIMING
FOR A BURST OF HEAVIER SNOW WILL OCCUR EARLIER IN THE DAY...BEFORE
SFC TEMPS HAVE A CHANCE TO RISE ABOVE FREEZING. BY THE TIME THAT
THE COLD FRONT REACHES THE ERN PORTIONS OF THE CWA...SFC
TEMPERATURES MAY WARM ABOVE FREEZING AND THE CHANCES FOR MUCH
MEASURABLE SNOWFALL WILL BE LOWER....WITH THE FAR SOUTHERN AND SERN
PORTION OF THE CWA...LOCATIONS GENERALLY SOUTH OF THE KANKAKEE RIVER
POSSIBLY ONLY SEEING SOME LIGHT FREEZING RAIN BEFORE BRIEFLY
CHANGING OVER TO SNOW AND THEN EVENTUALLY CHANGING OVER TO ALL RAIN
BY LATE MONDAY MORNING. SO...THE LATEST FORECAST UPDATE WILL
INCLUDE MEASURABLE SNOW NORTH OF THE IL/KANKAKEE RIVERS...WITH THE
I39 CORRIDOR SEEING AS MUCH A 1 INCH OF TOTAL ACCUMULATION...BEFORE
THE WARMER AIR MOVES IN AND MELTS ANY ACCUMULATING SNOW. LOCATIONS
NORTH OF THE RIVERS AND EAST OF I-39 SHOULD ONLY SEE AROUND A HALF
INCH SO SO OF SNOW. THE GREATEST CONCERN WILL BE IMPACTS ON TRAVEL
AS THE FREEZING/FROZEN PCPN WILL BE MOVING ACROSS THE AREA AROUND
THE MORNING RUSH HOURS...AND WITH EVEN LIGHT FREEZING RAIN...THERE
COULD BE TRAVEL DIFFICULTIES. BY LATE MORNING...SFC TEMPS SHOULD
RISE ABOVE FREEZING AND WITH SFC FLOW ONLY VEERING FROM SWLY TO WLY
WITH THE FROPA...LITTLE ACTUAL COOLING IS EXPECTED WITH THE FROPA
AND TEMPERATURES COULD REACH INTO THE UPPER 30S TO AROUND 40F BY
LATE MONDAY AFTERNOON. THE MORE SIGNIFICANT COLD ADVECTION WILL NOT
BEGIN UNTIL THE LATE EVENING HOURS AS THE NEXT SFC HIGH BUILDS
ACROSS THE NRN PLAINS...SETTING UP NWLY FLOW ACROSS THE REGION AND
BY TUESDAY MORNING...TEMPERATURES SHOULD DROP INTO THE MIDDLE TO
UPPER 20S.
KREIN
&&
.LONGER TERM...
427 AM CST
TUESDAY THROUGH NEXT SATURDAY...
THE EXTENDED FORECAST PERIOD LOOK TO BE GENERALLY QUIET ACROSS THE
MIDWEST AS DEEP LOW PRESSURE DEVELOPS OF THE MID ATLANTIC
COAST...SLOWING THE PROGRESSION OF THE SFC HIGH ACROSS THE AREA.
THE LATEST LONGER RANGE GUIDANCE SUGGESTS THAT THE CENTER OF THE
HIGH WILL BE SHUNTED INTO SERN CANADA BY THE DEEP LOW OFF THE EAST
COAST...WITH RIDGING EXTENDING THROUGH THE GREAT LAKES AND MIDDLE
MISSISSIPPI VALLEY THROUGH MUCH OF THE WEEK. TEMPERATURES SHOULD
GENERALLY BE SEASONABLE WITH HIGHS IN THE LOWER TO MIDDLE 30S
THROUGH THURSDAY WITH OVERNIGHT LOWS IN THE LOWER TO MIDDLE 20S.
PREVAILING HIGH PRESSURE WILL HELP KEEP THE REGION DRY AND NO
ADDITIONAL PCPN IS LIKELY THROUGH MUCH OF THE WEEK. THE MODELS
CONTINUE TO ADVERTISE A SIGNIFICANT WARMING TREND BY THE END OF THE
WEEK. THE MAIN IDEA IS THAT THE DEEP COASTAL LOW AND THE PARENT
UPPER LOW WILL REMAIN NEARLY STATIONARY OVER THE MID ATLANTIC
COAST...WHILE STRONG UPPER RIDGING BUILDS OVER THE WRN CONUS BY
FRIDAY...THE UPPER RIDGE IS EXPECTED TO BUILD OVER THE UPPER
MISSISSIPPI VALLEY AND ACROSS THE WRN GREAT LAKES BY NEXT SATURDAY.
THE LONGER RANGE TEMPERATURE GUIDANCE IS SUGGESTING THAT
TEMPERATURES COULD REACH INTO THE LOWER TO MIDDLE 40S BY FRIDAY AND
MIDDLE TO UPPER 40S FOR SATURDAY. HOWEVER...LONGER RANGE
TEMPERATURE GUIDANCE TENDS TO TREND A LITTLE CLOSER TO CLIMATOLOGY
TOWARD THE END OF THE FORECAST PERIOD...SO THE GOING FORECAST OF
MIDDLE TO UPPER 40S FOR NEXT SATURDAY COULD BE ON THE CONSERVATIVE
SIDE...AND WITH THE TYPE OF UPPER LEVEL PATTERN EVOLVING...THERE IS
THE POTENTIAL THAT TEMPERATURES FOR FRIDAY AND SATURDAY COULD VERY
WELL APPROACH OR EXCEED THE 50F MARK.
KREIN
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 09Z...
* SOUTHEAST WINDS AROUND 10 KT TODAY.
* LOWERING CIGS AND A PERIOD OF MIXED PRECIPITATION STARTING
AROUND OR JUST AFTER 12Z MONDAY.
MDB
//DISCUSSION...UPDATED 06Z...
HIGH PRESSURE IS OVERHEAD OF THE TERMINALS TONIGHT ALLOWING FOR
LIGHT NORTHEAST WINDS. WINDS WILL SWING AROUND TO THE SOUTHEAST
OVERNIGHT AND BE FAIRLY STEADY AROUND 10 KT DURING THE DAY. WINDS
WILL TURN TO THE SOUTH INTO MONDAY MORNING. VFR HIGH CLOUDS WILL
STREAM OVERHEAD THROUGH THE DAY TODAY AND TONIGHT BEFORE LOWERING
INTO MONDAY MORNING AHEAD OF A LOW PRESSURE SYSTEM/COLD FRONT. A
PERIOD OF MIXED PRECIPITATION IS EXPECTED MONDAY MORNING...LIKELY
STARTING JUST PRIOR TO 12Z AT RFD AND AROUND OR SOON AFTER 12Z AT
DPA/ORD/MDW/GYY. DETAILS ARE STILL IN FLUX BUT SOME SNOW/SLEET
ACCUMULATION IS POSSIBLE WITH A PERIOD OF IFR CIGS/VSBY POSSIBLE.
MDB
//ORD AND MDW CONFIDENCE...UPDATED 09Z...
* HIGH CONFIDENCE IN SOUTHEAST WINDS AROUND 10 KT TODAY.
* HIGH CONFIDENCE IN LOWERING CIGS AND A PERIOD OF MIXED
PRECIPITATION MONDAY MORNING.
MDB
//OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z...
MONDAY...CHANCE OF SLEET/SNOW MIX IN THE MORNING. MVFR/BRIEF IFR
POSSIBLE. S WINDS BECOMING W.
TUESDAY...VFR. NW WINDS BECOMING N.
WEDNESDAY...VFR. N WINDS BECOMING NE.
THURSDAY...VFR. S WINDS.
FRIDAY...VFR. S WINDS.
RATZER
&&
.MARINE...
251 AM CST
HIGH PRESSURE IS CENTERED OVER EASTERN ONTARIO EARLY THIS MORNING
WITH A RIDGE AXIS EXTENDING ACROSS LAKE MICHIGAN. THIS HAS ALLOWED
WINDS TO EASE AND TURN EAST TO NORTHEAST AND WILL ALLOW FOR A SHIFT
TO SOUTHEAST THROUGH THE MORNING. WILL ALLOW THE SMALL CRAFT
ADVISORY TO EXPIRE AS WINDS CONTINUE TO EASE ALLOWING WAVES TO BE ON
A DOWNWARD TREND. WILL CONTINUE WITH A 3-5 OCCASIONAL 7 FT FORECAST.
LOW PRESSURE IS OVER SOUTHERN SASKATCHEWAN AND EASTERN MONTANA AND
WILL BE MOVING EAST ALONG THE CANADIAN BORDER REACHING LAKE SUPERIOR
BY MIDDAY MONDAY. WITH THE HIGH PRESSURE RATHER STRONG THE PRESSURE
GRADIENT BETWEEN IT AND THE LOW WILL BE TIGHTENING THROUGH THE DAY
DESPITE THE LOW NOT BEING TERRIBLY DEEP. AS A RESULT WIND SPEEDS
WILL STEADILY INCREASE TO ABOUT 30 KT ACROSS MOST OF THE LAKE THIS
EVENING WITH SOME 35 KT GALE FORCE GUSTS POSSIBLE ACROSS CENTRAL AND
NORTHERN SECTIONS OVERNIGHT INTO EARLY MONDAY MORNING AS WINDS TURN
MORE SOUTHERLY. WILL ISSUE A SMALL CRAFT ADVISORY FOR MOST OF THE
ILLINOIS NEARSHORE FROM EARLY THIS EVENING THROUGH LATE MONDAY
MORNING AS WINDS AND WAVES COME UP. WINDS WILL THEN TURN
SOUTHWESTERLY MONDAY AFTERNOON AS THE LOW TRACKS TO THE EAST WITH
A SHIFT TO NORTHWEST MONDAY EVENING. COLDER AIR WILL SPREAD IN ON
A FAIRLY STRONG HIGH THAT WILL MOVE INTO THE MID AND UPPER
MISSISSIPPI RIVER VALLEY TUESDAY WHICH WILL ALLOW NORTHWEST WINDS
TO INCREASE EARLY TUESDAY MORNING AND TURN NORTH THROUGH THE DAY.
SPEEDS WILL THEN EASE INTO TUESDAY NIGHT AS THE HIGH MOVES CLOSER
THEN SPREADS ACROSS THE LAKE LATER WEDNESDAY. THE HIGH WILL BE
SLOW TO SHIFT TO THE EAST BUT WINDS WILL TURN WESTERLY AS IT DOES
THURSDAY THEN SOUTHWESTERLY THURSDAY NIGHT. STEADY SOUTHWEST WINDS
ARE THEN EXPECTED INTO THE WEEKEND AS THE HIGH SLOWLY MOVES OFF TO
THE EAST.
MDB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...LMZ740-LMZ741...6 PM SUNDAY TO 10 AM
MONDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
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WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
332 AM CST Sun Dec 7 2014
.SHORT TERM...(Today)
ISSUED AT 331 AM CST SUN DEC 7 2014
Clouds have cleared out to the south tonight for now, but they are
lingering very close-by. Satellite images already confirm increasing
high clouds from the west. The HRRR is advertising a return of low
clouds from the east-southeast across the eastern half of the area
between 15z/9am and 18z/Noon today, but that seems a bit aggressive
based on the current progression of clouds across Indiana and the
expected wind patterns this morning. Have increased clouds from the
west based on satellite and model consensus, but only trended minor
increases in clouds across the east during the day for now. Will
monitor the movement of low clouds toward our eastern counties for
potential sky cover updates in the short term.
Northeast flow early this morning is expected to evolve to east and
then southeast this afternoon, as high pressure centered over the
Lake Michigan departs farther east across the Great Lakes. The onset
of southeast winds will increase the potential return of low clouds
currently lingering across southern IL.
Temperatures today will only climb about 12-13F above morning lows
due to increasing clouds, with highs topping out in the upper 30s
to low 40s.
&&
.LONG TERM...(Tonight through Saturday)
ISSUED AT 331 AM CST SUN DEC 7 2014
High pressure continues to build into the region, although clouds
continue to dominate the Midwest. Plenty of moisture on sat imagery
obscuring the llvl clouds underneath. Clearing in patches certainly
not anticipated for long as llvl moisture remains trapped by
continuing strong inversion over the area. The dry air aloft is not
coincident with enough turbulence to break up the inversion and
erode the higher RH at roughly 925 mb. This dry air will also be
the first issue for eroding the approaching precip late Sun night
and into Monday. Models maintaining consistency with the last two
runs and continuity with one another with regards to approach and
qpf after midnight tonight and into Monday. A quick front moving
through the area bringing precip after midnight and through the day
Monday so far looks like mostly rain, though the nrn tier of the
state may see a bit more of a rain/snow/wintry mix. Concern remains
whether or not the models are too quick to overcome the dry air
aloft or whether or not the precip may be delayed slightly.
Beyond Monday`s cold front, temps cool briefly, then moderate back
into the 40s for highs through the end of the week. 00z GFS
agreeing with yesterdays 00z ECMWF and backing down from the precip
Wed/Thursday, instead dominating the sfc map with high pressure.
Pops mid week have been removed. Deepening low over the
northeast/east coast causing a bit of a back up across the CONUS as
it is slow to move and the models having some issue with pushing the
new wave inland on the Pacific coast and managing the ridging in the
middle. Seems from Friday and into the weekend the forecast becomes
a bit more problematic in the details as the models work out a
pattern shift again.
&&
.AVIATION...(For the 06Z TAFS through 06Z Sunday night)
ISSUED AT 1122 PM CST SAT DEC 6 2014
VFR CONDITIONS SHOULD PREVAIL OVER THE TAF SITES THROUGH THE
PERIOD...WITH A SLIGHT EXCEPTION FOR SPI AS HAZE STILL LINGERS
REDUCING VIS TO MVFR. HOWEVER...DO NOT THINK THIS WILL STICK
AROUND VERY LONG SINCE UPSTREAM AT AAA VIS HAS ALREADY CLEARED OUT
ABOVE 6SM FROM THE HIGH PRESSURE BUILDING OVER THE GREAT LAKES.
THEREFORE...USED A TEMPO GROUP FOR THE NEXT HOUR TO ACCOUNT FOR
THE REDUCED VIS IMPROVING TO VFR WITHIN THE HOUR. OTHERWISE...HIGH
CLOUDS ARE MOVING IN OVER THE TAF SITES WITH THE NEXT STORM SYSTEM
OUT IN THE PLAINS. ALONG WITH HIGH CLOUDS STREAMING IN...WINDS
SHOULD BEGIN TO SHIFT TO THE EAST AND THEN SOUTHEAST BY TOMORROW.
CIGS APPEAR TO REMAIN VFR THROUGH THE TAF PERIOD ACCORDING TO
GUIDANCE AND SOUNDINGS. PIA...BMI...AND SPI COULD SEE VCSH
TOMORROW NIGHT AROUND 03Z/04Z...BUT NOT CONFIDENT ENOUGH IN RAIN
FALLING OVER THE SITES BEFORE 06Z TO INCLUDE ANYTHING ELSE. THIS CAN
BE UPDATED IN LATER TAF ISSUANCES IF NEEDED.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Shimon
LONG TERM...HJS
AVIATION...ALW
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
902 AM CST SUN DEC 7 2014
...UPDATE TO SYNOPSIS...
.SYNOPSIS...
ISSUED AT 858 AM CST SUN DEC 7 2014
WV IMAGERY AND 12Z UPPER AIR ANALYSIS INDICATE AN UPPER LEVEL TROUGH
OF LOW PRESSURE TRANSITIONING EASTWARD ACROSS THE NORTHERN PLAINS.
MEANWHILE, A SECONDARY UPPER LEVEL SHORTWAVE IS MOVING EAST OUT OF
THE SOUTHERN ROCKIES INTO THE WESTERN HIGH PLAINS. NEAR THE SURFACE,
A WEAK LEE SIDE TROUGH OF LOW PRESSURE IS LOCATED NEAR AND ALONG THE
KANSAS AND COLORADO BORDER.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 202 AM CST SUN DEC 7 2014
WATER VAPOR LOOP INDICATING THE THE LATEST RAP AND NAM WERE DOING
A DECENT JOB ON THE TRACK OF AN UPPER LEVEL TROUGH AS IT MOVED
ACROSS EASTERN COLORADO EARLIER THIS MORNING. BOTH THE RAP AND NAM
MOVE THIS UPPER LEVEL FEATURE ACROSS WESTERN KANSAS BETWEEN 09Z
AND 15Z SUNDAY. MODEL SOUNDINGS INDICATING MOISTURE AHEAD OF THIS
UPPER LEVEL FEATURE WILL BE AT OR ABOVE THE 800MB LEVEL. IN
ADDITION TO THIS AREA OF MOISTURE THE SURFACE TO 1000 TO 2000FT
AGL LAYER WILL ALSO BE SATURATED EARLY THIS MORNING WITH THE
DEEPER LOW LEVEL MOISTURE APPEARING TO BE NEAR AND EAST OF HIGHWAY
283. BASED ON MODEL SOUNDINGS THE DEPTH OF THE LOW LEVEL MOISTURE
DOES NOT APPEAR DEEP ENOUGH TO SUPPORT DRIZZLE, HOWEVER WEAK LIFT
AHEAD OF THE UPPER LEVEL TROUGH MAY GIVE RISE TO SOME SPRINKLES OR
EVEN A BRIEF RAIN SHOWER...MAINLY IN NORTH CENTRAL AND SOUTH
CENTRAL KANSAS. WILL THEREFORE RETAIN SMALL CHANCE FOR
PRECIPITATION EARLY THIS MORNING EAST OF HIGHWAY 283.
WIDESPREAD STATUS AND FOG WILL BE LIKELY EARLY THIS MORNING. AT
THIS TIME THE AREA FAVORABLE FOR THE LOWER VISIBILITIES WILL BE
EAST OF HIGHWAY 83 THROUGH 15Z SUNDAY GIVEN THE LOW LEVEL MOISTURE
PROFILES AND BETTER UPSLOPE FLOW. BASED ON THE LATEST RAP AND HRRR
ALONG WITH MOST RECENT SURFACE OBSERVATIONS THE CURRENT DENSE FOG
ADVISORY HAS A GOOD HANDLE ON THIS SO NO MAJOR ADJUSTMENTS PLANNED
THIS MORNING. WILL CONTINUE TO MONITOR THIS AND ADJUST
ACCORDINGLY.
SUBSIDENCE DEVELOPING BEHIND THE UPPER LEVEL TROUGH DURING THE
LATE MORNING AND EARLY AFTERNOON WILL ALLOW FOR SOME AFTERNOON
SUNSHINE TO DEVELOP. AT THIS TIME CONFIDENCE IS NOT HIGH ON HOW
QUICKLY THE SKIES WILL CLEAR EAST OF DODGE CITY, HOWEVER BASED ON
THE NAM AND RAP TIMING OF THE CLEARING TREND FROM WEST TO EAST
ALONG WITH THE 850MB TEMPERATURES AT 21Z SUNDAY AND 00Z MONDAY THE
PREVIOUS FORECAST STILL LOOKS ON TRACK. WILL CONTINUE TO FAVOR THE
WARMER MAV GUIDANCE FOR HIGHS WEST OF ROUGHLY HIGHWAY 83 WHERE
MORE SUN THAN CLOUDS ARE EXPECTED DURING THE AFTERNOON. FURTHER
EAST FAVORED THE COOLER MET.
A SURFACE BOUNDARY WILL DROP SOUTH ACROSS WESTERN KANSAS LATE THIS
AFTERNOON AND EARLY TONIGHT. AS THIS BOUNDARY PASSES A
NORTHWESTERLY FLOW WILL DEVELOP AND DRIER AIR WILL RETURN TO
WESTERN KANSAS IN THE 0-1KM AGL LEVEL. BASED ON WESTERLY WINDS AT
10 KNOTS OR LESS AND DRIER AIR ADVECTING INTO WESTERN KANSAS WILL
THE PREVIOUS FORECAST WITH LOWS IN THE UPPER 20S TO LOWER 30S
STILL LOOKS ON TRACK.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 353 AM CST SUN DEC 7 2014
THE REST OF THE EXTENDED PERIOD IS SIMILAR TO THE LAST SEVERAL DAYS
AS FAR AS TEMPERATURES ARE CONCERNED, WITH RELATIVELY LOW IMPACT
SYNOPTIC SCALE WAVES EVERY COUPLE OF DAYS. DRIER AIR ALOFT WILL
INFLUENCE THE AREA MONDAY ON THE HEELS OF THE EXITING UPPER JET.
SUNNY SKY AND LIGHT SURFACE WINDS WILL LEAD TO TEMPERATURES MAINLY
INFLUENCED BY DIURNAL INSOLATION, WHILE EASTERLY SURFACE WINDS
DEVELOP OVERNIGHT INTO EARLY TUESDAY. SOME FOG OR STRATUS COULD
DEVELOP IN THE FAR WESTERN SECTIONS NEAR THE COLORADO LINE, BUT THIS
WOULD BE FAIRLY LIMITED AS OPPOSED THE MORE WIDESPREAD FOG OF LAST
NIGHT. THE ECMWF IS MORE AGGRESSIVE THAN THE GFS IN DEVELOPING RAIN
SHOWERS WITH THE POSITIVELY TILTED WAVE ON WEDNESDAY. FOR NOW LOW
PROBABILITIES EXIST FOR CENTRAL KANSAS WHERE BETTER MOISTURE SHOULD
BE PRESENT AS WELL AS BETTER STRETCHING DEFORMATION WITH THIS
PATTERN.
CONSIDERABLE UNCERTAINTY IN MESOSCALE DETAIL FOLLOWS BEYOND
WEDNESDAY AS THE ECMWF AND GFS BOTH AGREE ON AN INCOMING SYNOPTIC
LOW APPROACHING THE REGION WITH SOUTHERLY BOUNDARY LAYER WINDS. THE
DIFFERENCES EXIST IT A FAR MORE MOIST, STRATUS AND FOG TYPE PATTERN
OF THE EC AND MORE DRY BOUNDARY LAYER OR WESTERN KS WITH THE GFS
WHICH CAN ALSO MAKE LARGE DIFFERENCES IN EXPECTED TEMPERATURES.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 556 AM CST SUN DEC 7 2014
AN UPPER LEVEL TROUGH WILL MOVE THROUGH THE REGION THIS MORNING,
PRODUCING MAINLY ELEVATED VIRGA DUE TO A DRY LAYER JUST ABOVE THE
BOUNDARY LAYER. IFR/LIFR FOG AND STRATUS WAS ALSO WIDESPREAD
ACROSS THE AREA AFFECTING ALL THREE LOCAL TERMINALS, WHICH WILL BE
THE CASE THROUGH ABOUT MID MORNING.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 58 31 58 32 / 30 0 0 0
GCK 60 28 58 30 / 10 0 0 0
EHA 63 33 60 36 / 10 0 0 0
LBL 60 30 59 31 / 10 0 0 0
HYS 55 29 56 28 / 20 0 0 0
P28 57 33 58 33 / 30 0 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...JJOHNSON
SHORT TERM...BURGERT
LONG TERM...RUSSELL
AVIATION...RUSSELL
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
557 AM CST SUN DEC 7 2014
...UPDATED AVIATION...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 202 AM CST SUN DEC 7 2014
WATER VAPOR LOOP INDICATING THE THE LATEST RAP AND NAM WERE DOING
A DECENT JOB ON THE TRACK OF AN UPPER LEVEL TROUGH AS IT MOVED
ACROSS EASTERN COLORADO EARLIER THIS MORNING. BOTH THE RAP AND NAM
MOVE THIS UPPER LEVEL FEATURE ACROSS WESTERN KANSAS BETWEEN 09Z
AND 15Z SUNDAY. MODEL SOUNDINGS INDICATING MOISTURE AHEAD OF THIS
UPPER LEVEL FEATURE WILL BE AT OR ABOVE THE 800MB LEVEL. IN
ADDITION TO THIS AREA OF MOISTURE THE SURFACE TO 1000 TO 2000FT
AGL LAYER WILL ALSO BE SATURATED EARLY THIS MORNING WITH THE
DEEPER LOW LEVEL MOISTURE APPEARING TO BE NEAR AND EAST OF HIGHWAY
283. BASED ON MODEL SOUNDINGS THE DEPTH OF THE LOW LEVEL MOISTURE
DOES NOT APPEAR DEEP ENOUGH TO SUPPORT DRIZZLE, HOWEVER WEAK LIFT
AHEAD OF THE UPPER LEVEL TROUGH MAY GIVE RISE TO SOME SPRINKLES OR
EVEN A BRIEF RAIN SHOWER...MAINLY IN NORTH CENTRAL AND SOUTH
CENTRAL KANSAS. WILL THEREFORE RETAIN SMALL CHANCE FOR
PRECIPITATION EARLY THIS MORNING EAST OF HIGHWAY 283.
WIDESPREAD STATUS AND FOG WILL BE LIKELY EARLY THIS MORNING. AT
THIS TIME THE AREA FAVORABLE FOR THE LOWER VISIBILITIES WILL BE
EAST OF HIGHWAY 83 THROUGH 15Z SUNDAY GIVEN THE LOW LEVEL MOISTURE
PROFILES AND BETTER UPSLOPE FLOW. BASED ON THE LATEST RAP AND HRRR
ALONG WITH MOST RECENT SURFACE OBSERVATIONS THE CURRENT DENSE FOG
ADVISORY HAS A GOOD HANDLE ON THIS SO NO MAJOR ADJUSTMENTS PLANNED
THIS MORNING. WILL CONTINUE TO MONITOR THIS AND ADJUST
ACCORDINGLY.
SUBSIDENCE DEVELOPING BEHIND THE UPPER LEVEL TROUGH DURING THE
LATE MORNING AND EARLY AFTERNOON WILL ALLOW FOR SOME AFTERNOON
SUNSHINE TO DEVELOP. AT THIS TIME CONFIDENCE IS NOT HIGH ON HOW
QUICKLY THE SKIES WILL CLEAR EAST OF DODGE CITY, HOWEVER BASED ON
THE NAM AND RAP TIMING OF THE CLEARING TREND FROM WEST TO EAST
ALONG WITH THE 850MB TEMPERATURES AT 21Z SUNDAY AND 00Z MONDAY THE
PREVIOUS FORECAST STILL LOOKS ON TRACK. WILL CONTINUE TO FAVOR THE
WARMER MAV GUIDANCE FOR HIGHS WEST OF ROUGHLY HIGHWAY 83 WHERE
MORE SUN THAN CLOUDS ARE EXPECTED DURING THE AFTERNOON. FURTHER
EAST FAVORED THE COOLER MET.
A SURFACE BOUNDARY WILL DROP SOUTH ACROSS WESTERN KANSAS LATE THIS
AFTERNOON AND EARLY TONIGHT. AS THIS BOUNDARY PASSES A
NORTHWESTERLY FLOW WILL DEVELOP AND DRIER AIR WILL RETURN TO
WESTERN KANSAS IN THE 0-1KM AGL LEVEL. BASED ON WESTERLY WINDS AT
10 KNOTS OR LESS AND DRIER AIR ADVECTING INTO WESTERN KANSAS WILL
THE PREVIOUS FORECAST WITH LOWS IN THE UPPER 20S TO LOWER 30S
STILL LOOKS ON TRACK.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 353 AM CST SUN DEC 7 2014
THE REST OF THE EXTENDED PERIOD IS SIMILAR TO THE LAST SEVERAL DAYS
AS FAR AS TEMPERATURES ARE CONCERNED, WITH RELATIVELY LOW IMPACT
SYNOPTIC SCALE WAVES EVERY COUPLE OF DAYS. DRIER AIR ALOFT WILL
INFLUENCE THE AREA MONDAY ON THE HEELS OF THE EXITING UPPER JET.
SUNNY SKY AND LIGHT SURFACE WINDS WILL LEAD TO TEMPERATURES MAINLY
INFLUENCED BY DIURNAL INSOLATION, WHILE EASTERLY SURFACE WINDS
DEVELOP OVERNIGHT INTO EARLY TUESDAY. SOME FOG OR STRATUS COULD
DEVELOP IN THE FAR WESTERN SECTIONS NEAR THE COLORADO LINE, BUT THIS
WOULD BE FAIRLY LIMITED AS OPPOSED THE MORE WIDESPREAD FOG OF LAST
NIGHT. THE ECMWF IS MORE AGGRESSIVE THAN THE GFS IN DEVELOPING RAIN
SHOWERS WITH THE POSITIVELY TILTED WAVE ON WEDNESDAY. FOR NOW LOW
PROBABILITIES EXIST FOR CENTRAL KANSAS WHERE BETTER MOISTURE SHOULD
BE PRESENT AS WELL AS BETTER STRETCHING DEFORMATION WITH THIS
PATTERN.
CONSIDERABLE UNCERTAINTY IN MESOSCALE DETAIL FOLLOWS BEYOND
WEDNESDAY AS THE ECMWF AND GFS BOTH AGREE ON AN INCOMING SYNOPTIC
LOW APPROACHING THE REGION WITH SOUTHERLY BOUNDARY LAYER WINDS. THE
DIFFERENCES EXIST IT A FAR MORE MOIST, STRATUS AND FOG TYPE PATTERN
OF THE EC AND MORE DRY BOUNDARY LAYER OR WESTERN KS WITH THE GFS
WHICH CAN ALSO MAKE LARGE DIFFERENCES IN EXPECTED TEMPERATURES.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 556 AM CST SUN DEC 7 2014
AN UPPER LEVEL TROUGH WILL MOVE THROUGH THE REGION THIS MORNING,
PRODUCING MAINLY ELEVATED VIRGA DUE TO A DRY LAYER JUST ABOVE THE
BOUNDARY LAYER. IFR/LIFR FOG AND STRATUS WAS ALSO WIDESPREAD
ACROSS THE AREA AFFECTING ALL THREE LOCAL TERMINALS, WHICH WILL BE
THE CASE THROUGH ABOUT MID MORNING.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 58 31 58 32 / 10 0 0 0
GCK 60 28 58 30 / 10 0 0 0
EHA 63 33 60 36 / 0 0 0 0
LBL 60 30 59 31 / 10 0 0 0
HYS 55 29 56 28 / 10 0 0 0
P28 57 33 58 33 / 10 0 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 9 AM CST THIS MORNING FOR KSZ030-031-
045-046-064>066-078>081-088>090.
&&
$$
SHORT TERM...BURGERT
LONG TERM...RUSSELL
AVIATION...RUSSELL
AREA FORECAST DISCUSSION
NWS GOODLAND KS
344 AM MST SUN DEC 7 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 308 AM MST SUN DEC 7 2014
SHORT TERM FORECAST CONCERNS ARE THE POSSIBILITY OF FOG AND LOW
CLOUDS EXPANDING ACROSS PORTIONS OF THE FORECAST AREA EARLY THIS
MORNING AND THE POSSIBILITY OF FOG DEVELOPING AGAIN OVER PORTIONS
OF THE FORECAST AREA EACH OF THE NEXT COUPLE OF DAYS.
WIDESPREAD LOW CLOUDS AND FOG ARE PRESENT OVER CENTRAL KANSAS AND
EXTEND NORTH INTO SOUTHERN NEBRASKA. THE WESTERN PERIPHERY OF THIS
AREA HAS EXTENDED BACK INTO NORTHWEST KANSAS...BUT HAS NOT BEEN AS
EXTENSIVE AS PREVIOUSLY EXPECTED. HAVE TRIMMED BACK THE COVERAGE
FIRST THING THIS MORNING...BUT HAVE ALSO KEPT IT IN PLACE OVER THE
FAR EAST A LITTLE LONGER UNTIL THE UPPER TROUGH MOVES EAST AND
HELPS SWEEP OUT THE HIGH CLOUDS AND ALSO DRAGS THE SURFACE TROUGH
ACROSS THE FORECAST AREA.
WITH CLEARING EXPECTED EARLY OVER THE WEST WITH A DELAY OVER THE
EAST...WILL LIKELY SEE HIGHS AROUND 60 IN THE WEST WITH HIGHS
STRUGGLING TO REACH THE MIDDLE 50S OUT EAST WITH GUSTY NORTHWEST
WINDS MOVING IN MY MID DAY.
CONDITIONS WILL REMAIN DRY WITH TEMPERATURES WARMER THAN AVERAGE
THROUGH TUESDAY WITH GENERAL RIDGING ALOFT OVER THE ROCKIES AND
HIGH PLAINS.
THE NEXT BEST POSSIBILITY OF FOG ACROSS THE REGION WILL BE TUESDAY
NIGHT INTO EARLY WEDNESDAY MORNING. DEWPOINTS WELL INTO THE 30S
ARE EXPECTED IN THE RETURN FLOW AROUND THE SURFACE HIGH MOVING
INTO THE PLAINS STATES IN THE CONVERGENT AREA AHEAD OF THE SURFACE
TROUGH DEEPENING ALONG THE FRONT RANGE. HAVE LEFT ANY FOG OUT FOR
NOW AS THEE ARE SOME DIFFERENCES SHOWING UP BETWEEN THE ECMWF AND
NAM AND GFS AT THAT TIME THAT PUT A DAMPER ON CONFIDENCE.
.LONG TERM...(WEDNESDAY THROUGH SATURDAY)
ISSUED AT 230 AM MST SUN DEC 7 2014
A SIGNIFICANT WEATHER SYSTEM MAY AFFECT THE HIGH PLAINS LATE NEXT
WEEKEND. THIS SYSTEM IS THE MAIN EXTENDED FORECAST CONCERN AND THE
MAJORITY OF THIS DISCUSSION WILL FOCUS ON THE POSSIBILITIES.
FOR WEDNESDAY THROUGH SATURDAY...RIDGE OF HIGH PRESSURE ALOFT SHALL
DOMINATE THE WEATHER PATTERN. OVERALL...STILL ANTICIPATING VERY WARM
TEMPERATURES FOR THIS TIME OF YEAR. HOWEVER...FORECAST GUIDANCE HAS
LOWERED TEMPERATURES SLIGHTLY. UPON FURTHER REVIEW...IT APPEARS THE
MODELS ARE STRUGGLING WITH MOISTURE ADVECTION FROM THE SOUTH AND
SUBSEQUENT LOW CLOUDS...ESPECIALLY OVER THE EASTERN FORECAST REGION.
FELT CONFIDENT ENOUGH IN CONTINUING THE WARM FORECAST OVER THE WEST
AS DRIER AIR SHOULD REMAIN IN PLACE WITH DOWNSLOPE FLOW FROM THE
FRONT RANGE. FURTHER EAST...MORNING FOG/STATUS AND HIGHER MOISTURE
CONTENT OF ATMOSPHERE MAY LIMIT DAYTIME WARMING...THUS LEADING TO
COOLER HIGH TEMPERATURES.
CONCERNING NEXT WEEKENDS SYSTEM...MODELS HAVE BEEN CONSISTENT IN
SHOWING AT LEAST A STRONG DISTURBANCE MOVING THROUGH THE
SOUTHWESTERN UNITED STATES SATURDAY. THIS SYSTEM THEN EJECTS
NORTHEAST ACROSS THE HIGH PLAINS SUNDAY. MANY ASPECTS OF THIS SYSTEM
STILL NEED TO BE RESOLVED INCLUDING STRENGTH...TIMING AND MOST
PROBLEMATIC...PATH THIS SYSTEM TRAVELS. FORECAST ENSEMBLES INDICATE
A SIGNIFICANT AMOUNT OF SPREAD BETWEEN ENSEMBLE MEMBERS. THE
ENSEMBLE MEAN INDICATES A LARGE...OPEN TROUGH PASSING THROUGH WHILE
SOME OF THE MEMBERS AND THE 00Z OPERATIONAL GFS INDICATE A
STRONG...CLOSED LOW. THE OPERATIONAL EUROPEAN MODEL INDICATES THE
OPEN THOUGH SOLUTION SHOWN BY THE ENSEMBLE MEAN. THE EUROPEAN
ENSEMBLE ALSO SUGGESTS THE OPEN TROUGH SOLUTION BUT INDICATES A HIGH
VARIABILITY BETWEEN SOLUTIONS.
THE CLOSED LOW SOLUTION/POSSIBILITY IS EYE-OPENING IN THAT IT IS A
CLIMATOLOGICALLY FAVORABLE PATTERN FOR OUR REGION TO RECEIVE A
SIGNIFICANT WINTER STORM...POSSIBLY EVEN A BLIZZARD. THAT BEING
SAID...THERE IS JUST TOO MUCH VARIABILITY BETWEEN INDIVIDUAL MODELS
AND MODEL RUNS TO REALLY BEGIN HIGHLIGHTING A POTENTIAL HIGH-IMPACT
STORM. FOR EXAMPLE...YESTERDAYS 00Z GFS RUN SUGGESTED A STRONG
SYSTEM GOING SOUTH OF THE REGION...ACROSS THE BIG BEND COUNTRY OF
TEXAS. THE 06Z RUN SHOWED A STRONG SYSTEM EJECTING OVER THE COLORADO
FRONT RANGE AND HEADING TOWARDS RAPID CITY...WELL NORTH OF THE
FORECAST AREA. TODAYS 00Z OPERATIONAL GFS RUN BRINGS THE STRONG LOW
OVER THE TEXAS AND OKLAHOMA PANHANDLES WITH SIGNIFICANT AMOUNTS OF
PRECIPITATION ACROSS WESTERN KANSAS.
AS OF RIGHT NOW...AM FAIRLY CONFIDENT THAT A COLD FRONT WILL PASS
THROUGH AND WE HAVE A DECENT CHANCE AT SOME PRECIPITATION. HOW
MUCH...WHAT PRECIPITATION TYPE AND IF HIGH WINDS WILL ACCOMPANY THIS
SYSTEM IS EXTREMELY DIFFICULT TO PINPOINT AS OF RIGHT NOW DUE TO THE
DIFFERING POSSIBILITIES ON SYSTEM EVOLUTION. IT IS SOMETHING TO
WATCH FORECASTS UPDATES SO STAY TUNED!
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1000 PM MST SAT DEC 6 2014
KGLD...SOUTH WIND AROUND 15KTS AT TAF ISSUANCE WILL VEER TO THE
SOUTH AND DECREASE TO 10KTS BY 08Z UNDER A VFR OVERCAST SKY. STRATUS/BR
MAY REACH THE TERMINAL FROM THE EAST/SOUTHEAST AROUND 08Z WITH
IFR CIGS EXPECTED FROM 08Z-11Z WITH WINDS FROM THE SOUTH AROUND
10KTS. AROUND 12Z WINDS VEER TO THE SOUTHWEST 5-10KTS PUSHING THE
STRATUS SLOWLY EAST ALLOWING FOR VFR CONDITIONS TO RETURN. WINDS
THEN GO WEST UNDER 10KTS AROUND 15Z THEN SHIFT TO THE NORTHWEST
12G20KT POSSIBLY A BIT HIGHER IN THE 18Z-22Z TIMEFRAME UNDER JUST
A FEW FAIR WEATHER CLOUDS. BY 23Z WINDS DISSIPATE TO 5KTS OR SO BY
23Z THEN BACK TO THE WEST AT SIMILAR SPEEDS AROUND 05Z.
KMCK...SOUTHEAST WIND NEAR 10KT AT TAF ISSUANCE UNDER A VFR
OVERCAST SKY. STRATUS/DRIZZLE/BR WITH IFR CONDITIONS AND POSSIBLY
VLIFR CONDITIONS WITH VIS 1/2SM IN FG/DZ REACH THE TERMINAL FROM
THE EAST AROUND 09Z AND CONTINUE THROUGH 17Z BEFORE WINDS VEER
AROUND TO THE NORTHWEST NEAR 10KTS IN THE 17Z-20Z TIMEFRAME. THIS
WILL SCOUR OUT THE STRATUS PRODUCING VFR CONDITIONS FROM 17Z
THROUGH THE REST OF THE TAF PERIOD.
IT SHOULD BE NOTED THAT IN THESE SCENARIOS THAT HIGH RESOLUTION
MODELS OCCASIONALLY DONT PUSH THE STRATUS FAR ENOUGH WEST...BY AT
LEAST ONE ROW OF COUNTIES. IF THIS VERIFIES STRATUS/BR (POSSIBLY
FG WITH VLIFR CONDITIONS) MAY TAKE UP TO AN ADDITIONAL 3 HOURS TO
MOVE OUT OF BOTH TERMINALS. WITH A THICK OVERCAST SKY HARD TO
WATCH STRATUS PROGRESSION ON SATELLITE IMAGERY SO WILL HAVE TO
WATCH METARS AND HOURLY MODEL UPDATES FROM THE RUC AND HRRR.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...LOCKHART
LONG TERM...RRH
AVIATION...99
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
633 AM EST SUN DEC 7 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 538 AM EST SUN DEC 7 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A WELL-DEFINED SHORTWAVE
MOVING ACROSS MT EARLY THIS MORNING. THIS WAVE WILL BE THE FEATURE
OF INTEREST IN THE SHORT TERM AS IT SHIFTS E...REACHING THE UPPER
GREAT LAKES MON. AT THE SFC...SHORTWAVE WAS SUPPORTING LOW PRES OVER
SRN SASKATCHEWAN. TO THE E...HIGH PRES CENTER HAS SLIPPED E OF LAKE
SUPERIOR/UPPER MI. STRONG WAA/ISENTROPIC ASCENT REGIME BTWN THE
SHORTWAVE AND DEPARTING HIGH PRES HAS LED TO QUITE A BIT OF MID
LEVEL CLOUDINESS SPREADING INTO UPPER MI DURING THE NIGHT. RADARS
ARE ALSO SHOWING RETURNS...BUT SO FAR...THE FARTHEST S ANY -SN HAS
BEEN REPORTED IN OBS IS AT THUNDER BAY ONTARIO AS DRY AIR NOTED
BELOW 750MB ON 00Z KINL SOUNDING IS WORKING TO LIMIT SOUTHWARD
EXTENT OF -SN REACHING THE GROUND.
TODAY...SHORTWAVE OVER MT WILL MOVE TO THE ERN DAKOTAS WITH
ASSOCIATED SFC LOW REACHING FAR SE MANITOBA BY EVENING. STRONG
WAA/ISENTROPIC ASCENT WHICH IS CURRENTLY FOCUSED INTO NRN MN WILL
SHIFT E TODAY...BUT MODELS CONTINUE TO INDICATE THAT LOW-LEVELS WILL
FAIL TO MOISTEN ACROSS UPPER MI DUE TO A PERSISTENT FEED OF
LOW-LEVEL DRY AIR FROM DEPARTING HIGH PRES. TO THE W...AXIS OF
850-700MB MOISTURE TRANSPORT AND LOWERING CONDENSATION PRES DEFICITS
AHEAD OF SHORTWAVE REMAINS JUST W OF THE AREA THRU THE AFTN. SO...
NOT EXPECTING ANY PCPN DURING THE DAYLIGHT HRS TODAY. TEMPS SHOULD
REACH THE UPPER 20S/LWR 30S.
TONIGHT...AS RIBBON OF 850-700MB MOISTURE TRANSPORT...ISENTROPIC
ASCENT ENHANCED BY 850MB WINDS OF 40-50KT AND DEEP LAYER QVECTOR
CONVERGENCE IN ADVANCE OF APPROACHING SHORTWAVE TRANSLATE W-E...
CATEGORICAL POPS STILL APPEAR ON TRACK...SPREADING INTO WRN UPPER MI
THIS EVENING AND INTO THE CNTRL OVERNIGHT. SNOW MAY NOT REACH THE
FAR E AROUND KERY UNTIL TOWARD 12Z. AVERAGED MODEL QPF INDICATES 0.1
TO 0.2 INCHES OF QPF TONIGHT...SUGGESTING 1-2 INCHES OF SNOW IN
GENERAL AS SNOW TO WATER RATIOS SHOULDN`T BE MUCH MORE THAN 10-12 TO
1. THESE NUMBERS APPEAR ON TRACK FROM AN ISENTROPIC STANDPOINT AS
MIXING RATIOS OF AROUND 3G/KG ARE AVBL WITH CLOSE TO 6HRS OF ASCENT.
SNOW ACCUMULATIONS WILL BE LIGHTEST OVER THE E SINCE SNOW DOESN`T
BEGIN UNTIL NEAR THE END OF THE TONIGHT PERIOD. CLOUDS/PCPN/WINDS
WILL KEEP TEMPS FROM FALLING MORE THAN ROUGHLY 2-4 DEGREES FROM
TODAYS HIGH TEMPS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 407 AM EST SUN DEC 7 2014
MODELS ARE IN GOOD AGREEMENT MON THROUGH THU...WITH LESS AGREEMENT
FRI AND SAT. A SHORTWAVE WILL MOVE FROM WRN LAKE SUPERIOR TO NRN
LAKE SUPERIOR THEN TO ERN LAKE SUPERIOR STEADILY BETWEEN 12Z MON AND
06Z TUE. THIS WILL BRING A WEAKENING/BROADENING 1012-1016MB SFC LOW
ACROSS THE AREA AS THE SHORTWAVE MOVES ACROSS. THERMAL PROFILES WILL
SUPPORT ALL SNOW WITH THE EVENT FROM 12Z MON ON...BUT 850MB TEMPS
ONLY FALL TO A MINIMUM OF -8C AT 12Z TUE...WHICH IS WARMER THAN
PREVIOUS RUNS. THE DRY SLOT LOOKS TO BE MOVING INTO WRN UPPER MI
AROUND 12Z MON AS THE BEST FORCING IS OVER THE ERN CWA AND NRN LAKE
SUPERIOR. HAVE FOCUSED HIGHEST POPS IN THESE AREAS IN THE
MORNING...SHIFTING NE THROUGH THE DAY. WITH THE WRAP AROUND MOISTURE
AND COOL UPSLOPE FLOW...LAKE ENHANCED/UPSLOPE PRECIP WILL BECOME THE
FOCUS MON EVENING/MON NIGHT BEFORE DIMINISHING TUE AS A 1034MB SFC
RIDGE MOVES OVER LAKE SUPERIOR. DID REDUCE LAKE ENHANCED/UPSLOPE
POPS AS MODELS TREND WARMER WITH LOW LEVEL TEMPS. FOR MON THROUGH
TUE...GENERALLY HAVE SNOWFALL AMOUNTS OF 2-3 INCHES CLOSER TO LAKE
SUPERIOR...WITH 1 INCH OR SO INLAND.
UPPER RIDGING BUILDS INTO THE AREA THROUGH THE REST OF THE EXTENDED
WITH NO SIGNIFICANT SIGNAL FOR PRECIP. TEMPS WILL BE ON THE
INCREASE...WITH 850MB TEMPS INCREASING TO ABOVE 0C BY THU MORNING
AND MAKING IT UP TO AROUND 10C FRI NIGHT INTO SAT. OF
COURSE...TEMPERATURE INVERSION NEAR THE SFC WILL BE PRETTY STRONG SO
SFC TEMPS WILL BE MORE LIMITED...BUT COULD SEE HIGHS IN THE LOW 40S
IN SOME LOCATIONS ON SAT. MODELS DO SHOW A FEW HUNDREDTHS OF AN INCH
OF QPF FRI INTO SAT...BUT THINK THAT IS DUE TO MODELS OVERDOING LOW
LEVEL MOISTURE AS THEY NORMALLY DO WHEN THEY SIMULATE SNOWPACK
MELTING. DID NOT INCLUDE PRECIP IN THE FORECAST.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 632 AM EST SUN DEC 7 2014
PRES GRADIENT WILL TIGHTEN TODAY AS HIGH PRES EXITS TO THE E AND LOW
PRES APPROACHES FROM THE W. THIS WILL LEAD TO SOUTHERLY WINDS
INCREASING AND BECOMING GUSTY. OTHERWISE...WITH LOW-LEVELS REMAINING
DRY...VFR CONDITIONS WILL PREVAIL AT KIWD/KCMX/KSAW THRU THE AFTN.
TONIGHT...-SN DEVELOPING AHEAD OF THE APPROACHING LOW PRES SYSTEM
WILL SPREAD E INTO UPPER MI. ALL TERMINALS WILL FALL TO MVFR. WITH
SOMEWHAT HEAVIER SNOW EXPECTED AT KCMX/KSAW...THERE MAY BE SOME
PERIODS OF IFR VIS.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 538 AM EST SUN DEC 7 2014
TIGHTENING PRES GRADIENT AND PRES FALLS SHIFTING INTO THE UPPER
LAKES AHEAD OF APPROACHING LOW PRES WILL RESULT IN INCREASING
SOUTHERLY WINDS TODAY/TONIGHT. ACROSS THE E HALF OF LAKE SUPERIOR...
WIND GUSTS WILL LIKELY REACH GALE FORCE LATER THIS AFTN THRU TONIGHT
WHILE WINDS OVER THE W STAY MOSTLY BLO 30KT. AS LOW PRES/COLD FRONT
MOVE ACROSS THE UPPER LAKES LATE MON/MON EVENING...WINDS WILL SHIFT
TO THE NW-N. WITH SYSTEM TRENDING WEAKER AS IT DEPARTS...THESE WINDS
WILL LIKELY NOT BE AS STRONG AS PREVIOUSLY THOUGHT. SO...IT NOW
APPEARS GALES PROBABLY WON`T OCCUR ON THE BACKSIDE OF THE SYSTEM MON
NIGHT INTO EARLY TUE. HIGH PRES RIDGE ARRIVING TUE NIGHT/WED WILL
BRING A PERIOD OF LIGHTER WINDS UNDER 20KT THAT MAY LINGER ON THRU
THU AS WELL.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING FROM 7 PM THIS EVENING TO 10 AM EST MONDAY FOR
LSZ267.
GALE WARNING FROM 2 PM THIS AFTERNOON TO 10 AM EST MONDAY FOR
LSZ266.
GALE WARNING FROM 6 PM THIS EVENING TO 3 AM EST MONDAY FOR
LSZ248-249-265.
GALE WARNING FROM 7 PM THIS EVENING TO 3 AM EST MONDAY FOR
LSZ250.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...TITUS
AVIATION...ROLFSON
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
538 AM EST SUN DEC 7 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 538 AM EST SUN DEC 7 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A WELL-DEFINED SHORTWAVE
MOVING ACROSS MT EARLY THIS MORNING. THIS WAVE WILL BE THE FEATURE
OF INTEREST IN THE SHORT TERM AS IT SHIFTS E...REACHING THE UPPER
GREAT LAKES MON. AT THE SFC...SHORTWAVE WAS SUPPORTING LOW PRES OVER
SRN SASKATCHEWAN. TO THE E...HIGH PRES CENTER HAS SLIPPED E OF LAKE
SUPERIOR/UPPER MI. STRONG WAA/ISENTROPIC ASCENT REGIME BTWN THE
SHORTWAVE AND DEPARTING HIGH PRES HAS LED TO QUITE A BIT OF MID
LEVEL CLOUDINESS SPREADING INTO UPPER MI DURING THE NIGHT. RADARS
ARE ALSO SHOWING RETURNS...BUT SO FAR...THE FARTHEST S ANY -SN HAS
BEEN REPORTED IN OBS IS AT THUNDER BAY ONTARIO AS DRY AIR NOTED
BELOW 750MB ON 00Z KINL SOUNDING IS WORKING TO LIMIT SOUTHWARD
EXTENT OF -SN REACHING THE GROUND.
TODAY...SHORTWAVE OVER MT WILL MOVE TO THE ERN DAKOTAS WITH
ASSOCIATED SFC LOW REACHING FAR SE MANITOBA BY EVENING. STRONG
WAA/ISENTROPIC ASCENT WHICH IS CURRENTLY FOCUSED INTO NRN MN WILL
SHIFT E TODAY...BUT MODELS CONTINUE TO INDICATE THAT LOW-LEVELS WILL
FAIL TO MOISTEN ACROSS UPPER MI DUE TO A PERSISTENT FEED OF
LOW-LEVEL DRY AIR FROM DEPARTING HIGH PRES. TO THE W...AXIS OF
850-700MB MOISTURE TRANSPORT AND LOWERING CONDENSATION PRES DEFICITS
AHEAD OF SHORTWAVE REMAINS JUST W OF THE AREA THRU THE AFTN. SO...
NOT EXPECTING ANY PCPN DURING THE DAYLIGHT HRS TODAY. TEMPS SHOULD
REACH THE UPPER 20S/LWR 30S.
TONIGHT...AS RIBBON OF 850-700MB MOISTURE TRANSPORT...ISENTROPIC
ASCENT ENHANCED BY 850MB WINDS OF 40-50KT AND DEEP LAYER QVECTOR
CONVERGENCE IN ADVANCE OF APPROACHING SHORTWAVE TRANSLATE W-E...
CATEGORICAL POPS STILL APPEAR ON TRACK...SPREADING INTO WRN UPPER MI
THIS EVENING AND INTO THE CNTRL OVERNIGHT. SNOW MAY NOT REACH THE
FAR E AROUND KERY UNTIL TOWARD 12Z. AVERAGED MODEL QPF INDICATES 0.1
TO 0.2 INCHES OF QPF TONIGHT...SUGGESTING 1-2 INCHES OF SNOW IN
GENERAL AS SNOW TO WATER RATIOS SHOULDN`T BE MUCH MORE THAN 10-12 TO
1. THESE NUMBERS APPEAR ON TRACK FROM AN ISENTROPIC STANDPOINT AS
MIXING RATIOS OF AROUND 3G/KG ARE AVBL WITH CLOSE TO 6HRS OF ASCENT.
SNOW ACCUMULATIONS WILL BE LIGHTEST OVER THE E SINCE SNOW DOESN`T
BEGIN UNTIL NEAR THE END OF THE TONIGHT PERIOD. CLOUDS/PCPN/WINDS
WILL KEEP TEMPS FROM FALLING MORE THAN ROUGHLY 2-4 DEGREES FROM
TODAYS HIGH TEMPS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 407 AM EST SUN DEC 7 2014
MODELS ARE IN GOOD AGREEMENT MON THROUGH THU...WITH LESS AGREEMENT
FRI AND SAT. A SHORTWAVE WILL MOVE FROM WRN LAKE SUPERIOR TO NRN
LAKE SUPERIOR THEN TO ERN LAKE SUPERIOR STEADILY BETWEEN 12Z MON AND
06Z TUE. THIS WILL BRING A WEAKENING/BROADENING 1012-1016MB SFC LOW
ACROSS THE AREA AS THE SHORTWAVE MOVES ACROSS. THERMAL PROFILES WILL
SUPPORT ALL SNOW WITH THE EVENT FROM 12Z MON ON...BUT 850MB TEMPS
ONLY FALL TO A MINIMUM OF -8C AT 12Z TUE...WHICH IS WARMER THAN
PREVIOUS RUNS. THE DRY SLOT LOOKS TO BE MOVING INTO WRN UPPER MI
AROUND 12Z MON AS THE BEST FORCING IS OVER THE ERN CWA AND NRN LAKE
SUPERIOR. HAVE FOCUSED HIGHEST POPS IN THESE AREAS IN THE
MORNING...SHIFTING NE THROUGH THE DAY. WITH THE WRAP AROUND MOISTURE
AND COOL UPSLOPE FLOW...LAKE ENHANCED/UPSLOPE PRECIP WILL BECOME THE
FOCUS MON EVENING/MON NIGHT BEFORE DIMINISHING TUE AS A 1034MB SFC
RIDGE MOVES OVER LAKE SUPERIOR. DID REDUCE LAKE ENHANCED/UPSLOPE
POPS AS MODELS TREND WARMER WITH LOW LEVEL TEMPS. FOR MON THROUGH
TUE...GENERALLY HAVE SNOWFALL AMOUNTS OF 2-3 INCHES CLOSER TO LAKE
SUPERIOR...WITH 1 INCH OR SO INLAND.
UPPER RIDGING BUILDS INTO THE AREA THROUGH THE REST OF THE EXTENDED
WITH NO SIGNIFICANT SIGNAL FOR PRECIP. TEMPS WILL BE ON THE
INCREASE...WITH 850MB TEMPS INCREASING TO ABOVE 0C BY THU MORNING
AND MAKING IT UP TO AROUND 10C FRI NIGHT INTO SAT. OF
COURSE...TEMPERATURE INVERSION NEAR THE SFC WILL BE PRETTY STRONG SO
SFC TEMPS WILL BE MORE LIMITED...BUT COULD SEE HIGHS IN THE LOW 40S
IN SOME LOCATIONS ON SAT. MODELS DO SHOW A FEW HUNDREDTHS OF AN INCH
OF QPF FRI INTO SAT...BUT THINK THAT IS DUE TO MODELS OVERDOING LOW
LEVEL MOISTURE AS THEY NORMALLY DO WHEN THEY SIMULATE SNOWPACK
MELTING. DID NOT INCLUDE PRECIP IN THE FORECAST.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1210 AM EST SUN DEC 7 2014
MID CLOUDS WITH WAA AHEAD OF LOW PRESSURE MOVING INTO THE PLAINS
WILL PREVAIL AT THE TAF SITES OVERNIGHT INTO TODAY. AS HIGH PRESSURE
MOVES OFF TO THE EAST...SRLY WINDS WILL ALSO INCREASE TODAY AND
BECOME GUSTY BY AFTERNOON ESPECIALLY AT IWD AND SAW. AS A DISTURBANCE
AND THE PLAINS LOW MOVE INTO THE UPPER MS VALLEY...SOME LIGHT SNOW
IS EXPECTED TO DEVELOP OVER WRN UPPER MI BY LATE EVENING WITH CIGS
VSBY DROPPING INTO THE MVFR RANGE.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 538 AM EST SUN DEC 7 2014
TIGHTENING PRES GRADIENT AND PRES FALLS SHIFTING INTO THE UPPER
LAKES AHEAD OF APPROACHING LOW PRES WILL RESULT IN INCREASING
SOUTHERLY WINDS TODAY/TONIGHT. ACROSS THE E HALF OF LAKE SUPERIOR...
WIND GUSTS WILL LIKELY REACH GALE FORCE LATER THIS AFTN THRU TONIGHT
WHILE WINDS OVER THE W STAY MOSTLY BLO 30KT. AS LOW PRES/COLD FRONT
MOVE ACROSS THE UPPER LAKES LATE MON/MON EVENING...WINDS WILL SHIFT
TO THE NW-N. WITH SYSTEM TRENDING WEAKER AS IT DEPARTS...THESE WINDS
WILL LIKELY NOT BE AS STRONG AS PREVIOUSLY THOUGHT. SO...IT NOW
APPEARS GALES PROBABLY WON`T OCCUR ON THE BACKSIDE OF THE SYSTEM MON
NIGHT INTO EARLY TUE. HIGH PRES RIDGE ARRIVING TUE NIGHT/WED WILL
BRING A PERIOD OF LIGHTER WINDS UNDER 20KT THAT MAY LINGER ON THRU
THU AS WELL.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING FROM 7 PM THIS EVENING TO 10 AM EST MONDAY FOR
LSZ267.
GALE WARNING FROM 2 PM THIS AFTERNOON TO 10 AM EST MONDAY FOR
LSZ266.
GALE WARNING FROM 6 PM THIS EVENING TO 3 AM EST MONDAY FOR
LSZ248-249-265.
GALE WARNING FROM 7 PM THIS EVENING TO 3 AM EST MONDAY FOR
LSZ250.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...TITUS
AVIATION...JLB
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
1247 PM EST SUN DEC 7 2014
.SYNOPSIS...
MOISTURE IS EXPECTED TO SPREAD BACK INTO THE REGION LATE TONIGHT
AND MONDAY WITH WELL BELOW NORMAL TEMPERATURES AND CONSIDERABLE
CLOUDINESS. THERE WILL BE A CHANCE OF LIGHT RAIN BY MONDAY
AFTERNOON ESPECIALLY EAST MIDLANDS AS WEAK LOW PRESSURE DEVELOPS
OFFSHORE. HIGH PRESSURE WILL BUILD INTO THE AREA MID WEEK WITH
TEMPERATURES SLIGHTLY BELOW NORMAL.
&&
.NEAR TERM /THROUGH TONIGHT/...
UPPER TROUGH CONTINUES TO MOVE EAST OFFSHORE THE MID ATLANTIC
COAST...WHILE SURFACE HIGH PRESSURE BUILDS DOWN THE EAST COAST.
SATELLITE INDICATES AREA OF CLOUDINESS SHIFTING SOUTH...AND APPEARS
WILL SHIFT SOUTH OF OUR FORECAST AREA (FA) LATER THIS AFTERNOON.
SATELLITE ALSO SUGGESTS UPPER CLOUDINESS WILL MOVE INTO OUR REGION
TONIGHT AHEAD OF AN APPROACHING UPPER TROUGH...WHICH IS ALSO
EXPECTED TO LEAD TO WEAK ISENTROPIC LIFT LATE TONIGHT...CAUSING
ADDITIONAL LOWER TO MID LEVEL CLOUDINESS TO SPREAD BACK NORTH INTO
OUR FA. MODEL CONSENSUS HOLDS OF ON ANY MEASURABLE PRECIPITATION
FOR OUR FA THROUGH TONIGHT.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
UPPER TROUGH MOVING THROUGH THE GULF COAST AND SOUTHEASTERN STATES
MONDAY WILL RESULTING SOUTHWEST FLOW ALOFT OVER CAROLINAS. SURFACE
RIDGE EXTENDING FROM THE CANADIAN MARITIMES SOUTHWEST ACROSS THE
MID ATLANTIC TO THE CAROLINAS. WEAK SURFACE LOW WILL BE DEVELOPING
WELL EAST OF THE CAROLINA COAST BY MONDAY AFTERNOON. MODELS
CONTINUE TO INDICATE COLD AIR DAMMING IN THE CAROLINAS...ALTHOUGH
WEAK DUE TO LACK OF SIGNIFICANT ISENTROPIC LIFT AND SHALLOW
MOISTURE. EXPECT CONSIDERABLE CLOUDINESS PROBABLY OVERCAST BY LATE
MORNING WITH WEAK SOUTHEAST 850MB MOISTURE ADVECTION OFF ATLANTIC. AS
COASTAL LOW MOVES A LITTLE CLOSER TO THE NORTH CAROLINA COAST
MONDAY AFTERNOON AND EVENING IN RESPONSE TO APPROACHING MID LEVEL
SHORT WAVE TROUGH...WEAK LOW LEVEL CONVERGENCE NOTED IN THE NORTH
AND EAST AND ENOUGH LIFT FOR SOME PATCHY LIGHT RAIN/DRIZZLE. SO
RAISED POPS ESPECIALLY NORTH AND EAST MIDLANDS/PEE DEE THROUGH
EVENING...BUT QPF LIKELY QUITE LOW. TEMPERATURES...PREFER SREF MEAN
WHICH IS BELOW MOS AVERAGE/NEAR CURRENT FORECAST AND REASONABLE
BASED ON LOCAL WEDGE SCHEME. LINGERING CLOUDINESS MONDAY NIGHT MAY
RESULT IN OVERNIGHT TEMPERATURES ABOVE MOS MEAN. WEDGE ERODING
EARLY TUESDAY...SOME MORNING CLOUDS BUT EXPECT CLEARING THROUGH
DAY WITH DOWNSLOPE...CLOUDINESS LIKELY TO REMAIN MAINLY NORTH AND
WEST. GUIDANCE TEMPERATURES IN THE MID 50S ON TRACK.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
MODELS SHOW THE UPPER LOW CLOSING OFF AND BECOMING STACKED WITH
THE SURFACE LOW OVER THE NORTHEASTERN STATES ON WEDNESDAY.
SURFACE HIGH PRESSURE OVER THE CENTRAL CONUS WILL RIDGE INTO THE
SOUTHEASTERN STATES. THIS PATTERN WILL PROMOTE
WESTERLY/NORTHWESTERLY FLOW ACROSS THE FORECAST AREA. SURFACE HIGH
PRESSURE WILL CONTINUE TO DOMINATE THE PATTERN WEDNESDAY THROUGH
THE END OF THE LONG TERM PERIOD. STRONG NOCTURNAL COOLING WITH THE
RIDGE NEAR THE AREA SHOULD RESULT IN COLD LOW TEMPERATURES IN THE
UPPER 20S TO LOWER 30S WEDNESDAY THROUGH SUNDAY. MAX TEMPS ARE
FORECAST BELOW CLIMATOLOGY IN THE 50S EARLY IN THE PERIOD WITH
SLIGHT WARMING TREND INTO THE WEEKEND.
&&
.AVIATION /17Z SUNDAY THROUGH THURSDAY/...
CLOUDINESS...WITH MVFR CIGS...PUSHING SOUTH. TEMPO PERIODS OF MVFR
CIGS IN THE NEAR TERM AT OGB...OTHERWISE VFR CONDITIONS EXPECTED
THROUGH THIS EVENING. BREEZY NE WINDS INDICATING TREND TOWARDS
SLIGHTLY DECREASING SPEEDS.
SURFACE HIGH PRESSURE RIDGE WILL REMAIN ANCHORED ALONG THE EAST COAST
THROUGH MONDAY. MODELS INDICATING PREMISE FOR INCREASING CLOUDINESS
TO REENTER THE FORECAST AREA FROM THE SOUTH AND EAST LATE TONIGHT
DUE TO WEAK ISENTROPIC LIFT AHEAD OF AN APPROACHING UPPER
TROUGH...AND PERSIST THROUGH MUCH OF MONDAY. SOME MODEL DISCREPANCY
ON CEILING HEIGHTS...CHOSE TO LEAN TOWARDS RAP MODEL PROJECTION OF
MVFR CIGS...WHICH SEEMS PLAUSIBLE AT THIS TIME GIVEN THE SITUATION.
RAIN CHANCES APPEAR TOO LOW TO INCLUDE IN THE TAFS AT THIS TIME.
EXTENDED AVIATION OUTLOOK...MVFR RESTRICTIONS EXPECTED TO PERSIST
THROUGH TUESDAY MORNING. OTHERWISE...NO SIGNIFICANT IMPACTS TO
AVIATION EXPECTED LATE TUESDAY THROUGH THURSDAY.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...FLASH FLOOD WATCH THROUGH TUESDAY EVENING FOR SCZ030.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
317 PM CST SUN DEC 7 2014
SHORT TERM...TONIGHT THROUGH MONDAY...
314 PM CST
THE MAIN WEATHER CONCERN FOR TONIGHT INTO MONDAY IS THE QUICK HIT
OF A WINTERY MIX LATE TONIGHT INTO MONDAY MORNING...WITH THE
POTENTIAL OF BRIEF PERIOD OF A HEAVY BURST OF SNOW ACROSS FAR
NORTHERN ILLINOIS EARLY MONDAY MORNING DURING THE MORNING RUSH.
WATER VAPOR IMAGERY INDICATES OUR STORM SYSTEM OF INTEREST DIGGING
EAST-SOUTHEASTWARD ACROSS THE NORTHERN HIGH PLAINS. THE ASSOCIATED
AREA OF SURFACE LOW PRESSURE IS EXPECTED TO TRACK QUICKLY ALONG OR
NEAR THE CANADIAN BORDER THROUGH TUESDAY. WARM AIR
ADVECTION/ISENTROPIC ASCENT IS ALREADY RAMPING UP ACROSS THE AREA
OUT AHEAD OF THIS FEATURE...AND REGIONAL RADAR TRENDS ARE BEGINNING
TO SHOW PRECIPITATION DEVELOPING TO OUR WEST-NORTHWEST IN ASSOCIATION
WITH THE APPROACHING SURFACE FRONTAL BOUNDARY.
THE COMBINATION OF GOOD LARGE SCALE FORCING (Q-VECTOR CONVERGENCE)
ASSOCIATED WITH THE APPROACHING MID LEVEL SHORT WAVE ENERGY...ALONG
WITH WHAT APPEARS MAY END UP BEING A RATHER STOUT BAND OF MID LEVEL
FRONTOGENESIS...SHOULD PROVIDE A SHORT...BUT POTENTIALLY INTENSE
PERIOD OF PRECIPITATION ACROSS NORTHERN ILLINOIS/NORTHWESTERN
INDIANA EARLY MONDAY MORNING. MODEL SOUNDINGS ACROSS THE AREA ALL
INDICATE THE PRESENCE OF SOME VERY IMPRESSIVE MID LEVEL LAPSE RATES
(UP AROUND 7 DEGREES C/KM IN THE 700-500 MB LAYER) DURING THE PERIOD
OF MAXIMUM FORCING FOR ASCENT. IN ADDITION...CROSS SECTIONS ACROSS
NORTHERN ILLINOIS ALSO INDICATE THE PRESENCE OF NEGATIVE EPV...WITH
FOLDING THETA E SURFACES IN THE 500 TO 700 MB LAYER. THIS ALL
POINTS TO THE LIKELIHOOD OF A SHORT...BUT POTENTIALLY INTENSE BAND OF
PRECIPITATION DURING THE MORNING RUSH ACROSS NORTHERN
ILLINOIS/NORTHWESTERN INDIANA. THE CURRENT TIMING FOR THE CHICAGO
METRO AREA FOR THIS BAND OF HEAVY PRECIPITATION LOOKS TO BE IN THE
12 TO 15 UTC TIME FRAME...AND AN COUPLE HOURS EARLIER ACROSS NORTH
CENTRAL ILLINOIS.
MODEL GUIDANCE CONTINUES TO SUGGEST THERMAL PROFILES WILL BE
MARGINAL FOR SNOWFALL...WITH MAX LAYER WET BULB TEMPERATURES FROM
ZERO TO +1 CELSIUS. HOWEVER...GIVEN THE LIKELIHOOD OF AN INTENSE
PRECIPITATION RATES WITHIN THIS AREA OF PRECIP...I FEEL THAT
SNOW...WITH SLEET IS STILL LIKELY TO BE THE PRIMARY PRECIPITATION
TYPES...ESPECIALLY NORTH OF INTERSTATES 80 AND 88...WHERE THE
STRONG MESOSCALE FORCING...AND HENCE MOST INTENSE DYNAMIC COLUMN
COOLING WILL BE MOST LIKELY. HOWEVER...A VERY SHORT PERIOD OF
RAIN/FREEZING RAIN IS ALSO POSSIBLE AS THE PRECIPITATION INITIALLY
FIGHTS WITH A WARM BUT DRY LAYER AROUND 850 MB...BUT EVAPORATIVE
COOLING SHOULD LEAD TO A RATHER QUICK CHANGE OVER TO SNOW. A QUICK
INCH OF SNOW IS POSSIBLE...ESPECIALLY ALONG AND NORTH OF I88. WE
WILL ISSUE AN SPS TO HIGHLIGHT THIS...AS IT APPEARS IT WILL BE A
QUICK BURST OF SNOW DURING THE MONDAY MORNING RUSH.
SOUTH OF INTERSTATE 80 SOME SNOW AND SLEET IS STILL
POSSIBLE...BUT RAIN...AND EVEN A BRIEF PERIOD OF FREEZING RAIN IS
EXPECTED INTO MONDAY MORNING...DUE TO SLIGHTLY WARMER MID-LEVEL
TEMPERATURES. SURFACE TEMPERATURES WILL BE HOVERING RIGHT AROUND
FREEZING INTO EARLY MONDAY MORNING...SO SOME MINOR ICING IS
POSSIBLE...BUT I DONT SEE THIS AS MUCH OF FREEZING RAIN EVENT.
PRECIPITATION SHOULD BE QUICK TO MOVE EAST OF THE AREA...BY MIDDAY TO
EARLY AFTERNOON. GUIDANCE INDICATES THAT THE MID LEVELS WILL DRY OUT
IN A HURRY LATER MONDAY MORNING/EARLY AFTERNOON. THUS IT APPEARS ANY
LINGERING PRECIP WILL BE IN THE FORM OF VERY LIGHT RAIN OR
DRIZZLE...AND GIVEN THAT TEMPERATURES SHOULD WARM WELL INTO THE 30S
TOMORROW AFTERNOON AHEAD OF THE APPROACHING COLD FRONT...FREEZING
WILL NOT BE AN ISSUE DURING THE AFTERNOON.
KJB
&&
.LONG TERM...
258 PM CST
MONDAY NIGHT THROUGH NEXT WEEKEND...
AN EXTENSION OF THE UPPER LOW FROM THE AFOREMENTIONED SYSTEM WILL
MOVE OVER THE AREA MONDAY EVENING ALONG WITH REINFORCED LOW-LEVEL
COLD ADVECTION AS A SECONDARY MORE CONTINENTAL COLD FRONT MOVES
SOUTHWARD THROUGH THE AREA. FORECAST LIFT IS DISJOINTED SO NOT
EXPECTING MUCH IF ANY PRECIPITATION...BUT DID ADD A CHANCE OF
DRIZZLE AND FLURRIES MONDAY EVENING. VERTICAL SATURATION PROFILES
REMAIN IFFY FOR ICE PRESENCE SO FELT COMFORTABLE MENTIONING EITHER
OR. WITH TEMPERATURES COOLING CANT RULE OUT FREEZING DRIZZLE IF SOME
PATCHY DRIZZLE WERE TO OCCUR...BUT AGAIN A LOW CHANCE.
AS THE SYSTEM MOVES EAST-SOUTHEAST ON TUESDAY IT WILL ABSORB A
SOUTHERN STREAM SYSTEM PRESENTLY ACROSS THE SOUTHERN
PLAINS...FORMING A DEEP OCCLUDING LOW ACROSS THE NEW ENGLAND REGION.
LONG RANGE GUIDANCE IS IN GOOD AGREEMENT WITH THIS. WITH BLOCKED
FLOW OVER THE NORTHERN/MID ATLANTIC...THIS LOW WILL MOVE LITTLE
THROUGH MIDWEEK...WITH THE OVERALL PATTERN BECOMING BLOCKED AND
CONSIDERABLY SLOWER ACROSS THE COUNTRY. THIS MEANS QUIET WEATHER FOR
OUR AREA FROM TUESDAY ONWARD. TEMPERATURES LOOK TO BE NEAR
NORMAL...MAYBE SLIGHTLY BELOW...DURING MIDWEEK.
A BUILDING UPPER RIDGE ACROSS THE ROCKIES DURING MIDWEEK WILL
INCH/LEAN EASTWARD...HOWEVER THE LOW-LEVEL THERMAL RIDGE WILL LAG
THIS. WHILE HEIGHTS WILL BE WELL ABOVE NORMAL OVER THE AREA...THE
GREATEST HEIGHT AND THERMAL ANOMALIES LOOK TO REMAIN TO THE WEST AND
NORTHWEST OF THE AREA ON ENSEMBLE GUIDANCE AND THE TREND HAS BEEN
THIS WAY. TEMPERATURES ARE STILL ON THEIR WAY TO ABOVE NORMAL WITH
THE CHANCE OF HAVING NEXT WEEKEND IN THE 50S...BUT RIGHT NOW WITHOUT
STRONG LOW-LEVEL WARM ADVECTION THE MAGNITUDE MAY BE HINDERED SOME.
DO THINK THE GFS IS TOO ROBUST ON LOW-LEVEL MOISTURE OVER THE
WEEKEND SO HAVE LEANED MORE TOWARD THE MORE SUNNY ECMWF /ESPECIALLY
FOR SATURDAY/. THE ECMWF HAS HIGHS IN THE MID-UPPER 40S. GIVEN THE
PATTERN...ANY PRECIPITATION CHANCES ARE LIKELY TO SLOW FURTHER SO
HAVE BACKED ANY UP UNTIL SUNDAY NIGHT.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* SOUTHEAST WINDS AROUND 10 KT THROUGH EARLY EVENING.
* BAND OF MIXED PRECIPITATION EXPECTED MONDAY MORNING. MAY START
AS -FZRA THEN TURN TO SHORT PERIOD OF SLEET/SNOW. IFR CIGS/VSBY
LIKELY FOR A FEW HOUR PERIOD.
KMD
//DISCUSSION...UPDATED 18Z...
NOT MUCH CHANGE IN THINKING ON THE MIXED PRECIPITATION POTENTIAL
MONDAY MORNING...WITH A VERY SLIGHT SLOWING TREND IN THE ABILITY
OF PRECIPITATION TO REACH THE GROUND. 12Z-14Z SEEMS TO BE THE
MOST LIKELY WINDOW FOR A BURST OF WET SNOW/SLEET ACROSS THE
CHICAGO LAND TERMINALS...10Z-12Z FARTHER WEST TOWARDS ROCKFORD.
AS MENTIONED IN EARLIER DISCUSSIONS...PRECIPITATION MAY START AS
LIGHT FREEZING RAIN IF THE INITIAL DRY AIR CAN BE OVERCOME BUT
CURRENT TRENDS SUGGEST THAT THIS WINDOW MAY BE VERY SHORT. THE AIR
MASS IN THE MAIN FORCING SHOULD BE COLDER AND SUPPORT A TRANSITION
TO FROZEN PRECIPITATION. THIS WOULD RESULT IN A BRIEF PERIOD OF
SLUSHY SNOW/SLEET ACCUMULATIONS NO HIGHER THAN 1 INCH AS SURFACE
TEMPERATURES HOVER AROUND THE FREEZING MARK...BUT IT COULD COME
DOWN RATHER QUICKLY. IFR CONDITIONS ARE EXPECTED DURING THIS TIME WITH
POSSIBLE LIFR CONDITIONS FOR A SHORT TIME AS WELL IF THE PRECIP
TYPE TURNS TO ALL SNOW.
AFTERWARDS THE TREND IS TOWARD KEEPING SOME LOWER CIGS AROUND IN
THE MVFR CATEGORY...WITH WINDS SHIFTING TO WESTERLY. PRECIPITATION
TRANSITIONS TO LIGHT RAIN/DRIZZLE AFTER MAIN BAND PUSHES THROUGH.
KMD
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* HIGH CONFIDENCE IN WIND TRENDS.
* MEDIUM-HIGH CONFIDENCE IN A BAND OF MIXED PRECIPITATION
OCCURRING MONDAY MORNING WITH IFR CONDITIONS. MEDIUM CONFIDENCE
IN PROGRESSION OF PRECIP TYPE AND TIMING...THOUGH LOW CONFIDENCE
ON FZRA.
KMD
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
MONDAY NIGHT...VFR. NW WINDS.
TUESDAY...VFR. NW WINDS BECOMING N.
WEDNESDAY...VFR. N WINDS.
THURSDAY...VFR. S WINDS.
FRIDAY...VFR. S WINDS.
SATURDAY...VFR. S WINDS.
MDB
&&
.MARINE...
203 PM CST
SOUTHEAST TO SOUTH WINDS WILL CONTINUE TO INCREASE TONIGHT AHEAD OF
QUICK MOVING LOW PRESSURE ACROSS THE UPPER MIDWEST...INCLUDING
POSSIBLY TEMPORARY GALES ACROSS THE FAR NORTH. THE SOMEWHAT ONSHORE
FLOW TONIGHT INTO NORTHEAST ILLINOIS...MAINLY NORTH OF
CHICAGO...STILL LOOKS TO BRING SMALL CRAFT ADVISORY CONDITIONS THERE
INTO EARLY MONDAY MORNING. AS THE LOW TRACKS FROM LAKE SUPERIOR TO
LAKE HURON MONDAY AND MONDAY NIGHT...WINDS WILL TURN TO WEST ON
MONDAY EVENING AND THEN NORTHWEST LATE MONDAY NIGHT AND FINALLY TO
NORTH BY MIDDAY TUESDAY. WIDESPREAD 30 KT WINDS ARE EXPECTED
TUESDAY IN THIS COLD AIR ADVECTION. THE WEATHER PATTERN IS
FORECAST TO BECOME VERY BLOCKED FOR THE LATTER HALF OF THE
WEEK...WITH THE LAKE LOCKED BETWEEN A RIDGE TO ITS IMMEDIATE WEST
AND A LOW OVER THE NORTHEAST. THIS MEANS GENERALLY 10-15 KT
NORTHWEST TO WEST WINDS.
MTF
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WINTHROP HARBOR TO NORTHERLY IS UNTIL 10 AM MONDAY.
&&
$$
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[top]
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
304 PM CST Sun Dec 7 2014
.SHORT TERM...(Tonight)
ISSUED AT 304 PM CST SUN DEC 7 2014
Mid and high clouds are expansive across the forecast area this
afternoon, although some patches of stratocumulus have been
developing. Larger shield of clouds around 1500 feet starting to
cross the Missouri/Illinois border as well. Water vapor imagery
showing the incoming clipper system quite nicely over the Dakotas.
Latest surface map shows the low center over northern North Dakota,
and its trailing cold front into central Nebraska and western
Kansas.
Main concern is with precipitation types across the north. Still
appears that the precipitation in our area will hold off until after
midnight, and not reach areas east of I-57 until sunrise. The
remainder of the morning model suite has arrived, and all are
generally trending warmer ahead of the incoming clipper. The NAM
and RAP are most prominent with the 850 mb warm nose, around +4 to
+5C, and suggest all rain even in the far north. The GFS, ECMWF and
Canadian models with a more modest +1 to +3C. These all indicate
surface temperatures above freezing as well, but would indicate a
bit of sleet potential as well. Have leaned a bit more on the warmer
side of the guidance and kept it mostly rain, but included a slight
chance of freezing rain from around Champaign northwest through
Bloomington to Minonk. Surface temperatures will remain borderline
with the ice potential, but lows around 33-34 degrees will be common
in much of the forecast area.
&&
.LONG TERM...(Monday through Sunday)
ISSUED AT 304 PM CST SUN DEC 7 2014
The initial shortwave feature associated with the clipper system
will cross the central IL forecast area by mid afternoon, bringing
the best lift and precipitation with the system. Models over the
past day have trended upward with precipitation amounts and now
yield a consensus of a few hundredths to a tenth of an inch.
Precipitation type could linger as freezing rain from around
Danville northwestward until around 8 a.m. but surface temperatures
will quickly rise above freezing to yield all rain through the day.
Subsidence aloft will follow the initial shortwave causing
precipitation to diminish from west to east late morning through
afternoon. Shallow stratus looks to continue into the evening as
cold advection in northwest winds push into the region. Model
soundings indicate the moisture trapped below a subsidence inversion
will be shallow enough that any precipitation would likely be
drizzle, although some potential for snow flurries with little
accumulation exists.
Below normal temperatures in NW flow will continue for midweek. A
deepening low over the east coast will likely cause a blocked
pattern with a slowly moving ridge over the plains. Models have been
inconsistent with handling next weekend but have trended forecast
toward the ECMWF solution which holds the ridge further west and
looks more reasonable. As a result, will hold drier and slightly
cooler temperatures longer into the weekend.
&&
.AVIATION...(For the 18Z TAFS through 18Z Monday afternoon)
ISSUED AT 1136 AM CST SUN DEC 7 2014
Main time frame of concern will be after 06Z, as a clipper system
moves in from the west. Ahead of it, VFR conditions to continue
with only high clouds present, and southeast winds gradually
trending more southerly this evening. The clipper is expected to
spread light rain into the KPIA/KBMI areas in the 09-12Z time
frame. Surface temperatures may be cold enough for some brief
freezing rain especially at KBMI, but have held off on mention for
this for now as confidence is not especially high. Further south,
have kept the VCSH mention as there will still be some dry air to
overcome late tonight. Have kept the development of MVFR
conditions later in the period as visibilities lower ahead of the
clipper, and ceilings around 1500 feet or so should overspread the
region late tonight.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Geelhart
LONG TERM...Onton
AVIATION...Geelhart
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1147 AM CST SUN DEC 7 2014
.SHORT TERM...
427 AM CST
A HIGH AMPLITUDE...PROGRESSIVE UPPER LEVEL PATTERN WILL BRING VERY
CHANGEABLE WEATHER TO THE REGION FOR THE NEXT SEVERAL DAYS...THOUGH
THE MAIN CONCERN WILL BE A WINTRY MIXED PCPN EVENT FOR SUNDAY NIGHT
INTO MONDAY MORNING.
THROUGH MONDAY NIGHT...
FOR THE REMAINDER OF THE NIGHT AND INTO SUNDAY MORNING...CONDITIONS
WILL REMAIN QUIET WITH INCREASING HIGH CLOUD COVER WHICH WILL LIMIT
ANY FURTHER RADIATIVE COOLING AND TEMPERATURES ACROSS THE REGION
SHOULD BOTTOM OUT IN THE LOWER TO MIDDLE 20S...EXCEPT FOR DOWNTOWN
CHICAGO WHICH WILL ONLY DROP TO AROUND 30F. THE REMAINDER OF SUNDAY
SHOULD BE RELATIVELY INNOCUOUS WITH CONTINUED INCREASING MID AND
HIGH LEVEL CLOUD COVER. AS THE CENTER OF A LARGE AREA OF HIGH
PRESSURE SHIFTS FROM THE UPPER GREAT LAKES TO ERN CANADA...A LOW
PRESSURE SYSTEM WILL MOVE OUT OF THE SRN CANADIAN ROCKIES...DRAGGING
A WEAK COLD FRONT INTO THE PLAINS. LOW LEVEL FLOW WILL BECOME MORE
SELY AHEAD OF THE APPROACHING SYSTEM...THOUGH WITH HIGH PRESSURE
RIDGING STILL NOSING SOUTHWEST INTO THE LOWER MISSISSIPPI
VALLEY...EVEN AS TEMPERATURES RISE INTO UPPER 30S...DEWPOINTS WILL
REMAIN RELATIVELY LOW...REMAINING IN THE LOW 20S.
AS THE SYSTEM APPROACHES THE REGION...CONCERNS WILL BECOME PCPN TYPE
AND AMOUNT WITH THE SYSTEM. PREVIOUS MODEL RUNS HAD MAINTAINED A
RELATIVELY DRY ENVIRONMENT AS THE GULF OF MEXICO REMAIN CUT OFF FROM
THE NRN STREAM SYSTEM AND ANY LOW LEVEL MOISTURE TRANSPORT WILL HAVE
TO TAKE A LONG PATH AROUND THE PERIPHERY OF THE SFC RIDGE BEFORE
REACHING INTO THE MIDDLE MISSISSIPPI VALLEY. HOWEVER...THE LATEST
MODEL RUNS ARE INDICATING MORE MOISTURE AVAILABLE TO THE SYSTEM WITH
FORECAST PWATS AROUND 3/4 INCH AND MANY MODELS ARE PAINTING MORE QPF
THAN PREVIOUS RUNS. HAVE SOME CONCERN THAT THE MODELS ARE OVER
FORECASTING MOISTURE CONTENT AND QPF...SO HAVE GONE WITH A MORE
CONSERVATIVE APPROACH TO QPF AMOUNTS THAT WHAT MANY OF THE MODELS
WOULD SUGGEST. HOWEVER...STILL FEEL THAT THERE WILL BE ENOUGH DEEP
LAYER MOISTURE TO PRODUCE MEASURABLE PCPN ACROSS THE REGION. THE
REAL CONCERN WILL BE PCPN TYPE WITH AMOUNTS MORE OF A SECONDARY
CONCERN. THIS IS LARGELY BECAUSE THE GUIDANCE IS INDICATING AN
INTRUSION OF WARM AIR ABOVE A NEARLY SATURATED...BUT BELOW FREEZING
SFC LAYER. THE LATEST RUNS OF THE LOCAL WRFARW...WHICH WAS LARGELY
FOLLOWED FOR THE FINER SCALE DETAILS OF THE PCPN TYPE TREND
INDICATES A RATHER THICK WARM LAYER WITH MAX TEMPS WITHING THE WARM
LAYER OF +3 TO +5C ABOVE A SURFACE BASED INVERSION WITH SFC
TEMPERATURES ARND 30F BY THE TIME THE LEADING EDGE OF THE PCPN MOVES
INTO THE FAR NWRN PORTIONS OF THE CWA. THE LATEST GUIDANCE SUGGESTS
THAT PCPN COULD MOVE INTO THE NWRN PORTIONS OF THE CWA BY ARND
06Z...AND WITH SFC TEMPS OF 30F...BELOW THE DEEP WARM LAYER...PCPN
SHOULD LARGELY BE FREEZING RAIN. THE LEADING EDGE OF THE FREEZING
RAIN SHOULD STEADILY CROSS THE CWA...REACHING THE CHICAGO METRO AREA
DURG THE PREDAWN HOURS. A RATHER STRONG MID LEVEL SHORTWAVE...WITH
700MB OMEGA MAX MOVING ACROSS THE AREA...THERE WILL LIKELY BE A
PERIOD OF SLEET MIXING IN WITH THE FREEZING RAIN DURG THE MORNING
HOURS. PCPN TYPE BECOME A LITTLE MORE COMPLICATED BY LATE MORNING
AND INTO THE AFTERNOON HOURS. MID LEVEL DRY AIR SHOULD MOVE IN
RELATIVELY QUICKLY AS THE HEAVIEST BAND OF PCPN TRACKS FROM WEST TO
EAST ACROSS THE AREA. THE MID LEVEL DRYING COULD OCCUR BEHIND THE
PASSAGE OF THE SFC COLD FRONT. HOWEVER...SINCE THIS SYSTEM IS A
MODIFIED PACIFIC SYSTEM...TEMPERATURES SHOULD NOT DROP OFF QUICKLY
OR SIGNIFICANTLY FOLLOWING THE FROPA...BUT THERE COULD BE A QUICK
BURST OF MODERATE SNOW FOR A SHORT PERIOD WITH THE FROPA AS THE MID
LEVEL WARM LAYER ERODES AND THE ENTIRE COLUMN DROPS BELOW FREEZING.
LATEST THINKING WITH THAT THE ENTIRE CWA SHOULD SEE A LEAST A LIGHT
GLAZING OF FREEZING RAIN...WITH PERHAPS A LIGHT ICE ACCUMULATION
OVER THE NORTHERN PORTIONS OF THE CWA...WHERE QPF AND FORCING WILL
BE STRONGER. ALSO...IT LOOKS LIKE THE ROCKFORD AREA SHOULD HAVE THE
BETTER OPPORTUNITY FOR ACCUMULATING SNOWFALL AS THE THE BEST TIMING
FOR A BURST OF HEAVIER SNOW WILL OCCUR EARLIER IN THE DAY...BEFORE
SFC TEMPS HAVE A CHANCE TO RISE ABOVE FREEZING. BY THE TIME THAT
THE COLD FRONT REACHES THE ERN PORTIONS OF THE CWA...SFC
TEMPERATURES MAY WARM ABOVE FREEZING AND THE CHANCES FOR MUCH
MEASURABLE SNOWFALL WILL BE LOWER....WITH THE FAR SOUTHERN AND SERN
PORTION OF THE CWA...LOCATIONS GENERALLY SOUTH OF THE KANKAKEE RIVER
POSSIBLY ONLY SEEING SOME LIGHT FREEZING RAIN BEFORE BRIEFLY
CHANGING OVER TO SNOW AND THEN EVENTUALLY CHANGING OVER TO ALL RAIN
BY LATE MONDAY MORNING. SO...THE LATEST FORECAST UPDATE WILL
INCLUDE MEASURABLE SNOW NORTH OF THE IL/KANKAKEE RIVERS...WITH THE
I39 CORRIDOR SEEING AS MUCH A 1 INCH OF TOTAL ACCUMULATION...BEFORE
THE WARMER AIR MOVES IN AND MELTS ANY ACCUMULATING SNOW. LOCATIONS
NORTH OF THE RIVERS AND EAST OF I-39 SHOULD ONLY SEE AROUND A HALF
INCH SO SO OF SNOW. THE GREATEST CONCERN WILL BE IMPACTS ON TRAVEL
AS THE FREEZING/FROZEN PCPN WILL BE MOVING ACROSS THE AREA AROUND
THE MORNING RUSH HOURS...AND WITH EVEN LIGHT FREEZING RAIN...THERE
COULD BE TRAVEL DIFFICULTIES. BY LATE MORNING...SFC TEMPS SHOULD
RISE ABOVE FREEZING AND WITH SFC FLOW ONLY VEERING FROM SWLY TO WLY
WITH THE FROPA...LITTLE ACTUAL COOLING IS EXPECTED WITH THE FROPA
AND TEMPERATURES COULD REACH INTO THE UPPER 30S TO AROUND 40F BY
LATE MONDAY AFTERNOON. THE MORE SIGNIFICANT COLD ADVECTION WILL NOT
BEGIN UNTIL THE LATE EVENING HOURS AS THE NEXT SFC HIGH BUILDS
ACROSS THE NRN PLAINS...SETTING UP NWLY FLOW ACROSS THE REGION AND
BY TUESDAY MORNING...TEMPERATURES SHOULD DROP INTO THE MIDDLE TO
UPPER 20S.
KREIN
&&
.LONG TERM...
427 AM CST
TUESDAY THROUGH NEXT SATURDAY...
THE EXTENDED FORECAST PERIOD LOOK TO BE GENERALLY QUIET ACROSS THE
MIDWEST AS DEEP LOW PRESSURE DEVELOPS OF THE MID ATLANTIC
COAST...SLOWING THE PROGRESSION OF THE SFC HIGH ACROSS THE AREA.
THE LATEST LONGER RANGE GUIDANCE SUGGESTS THAT THE CENTER OF THE
HIGH WILL BE SHUNTED INTO SERN CANADA BY THE DEEP LOW OFF THE EAST
COAST...WITH RIDGING EXTENDING THROUGH THE GREAT LAKES AND MIDDLE
MISSISSIPPI VALLEY THROUGH MUCH OF THE WEEK. TEMPERATURES SHOULD
GENERALLY BE SEASONABLE WITH HIGHS IN THE LOWER TO MIDDLE 30S
THROUGH THURSDAY WITH OVERNIGHT LOWS IN THE LOWER TO MIDDLE 20S.
PREVAILING HIGH PRESSURE WILL HELP KEEP THE REGION DRY AND NO
ADDITIONAL PCPN IS LIKELY THROUGH MUCH OF THE WEEK. THE MODELS
CONTINUE TO ADVERTISE A SIGNIFICANT WARMING TREND BY THE END OF THE
WEEK. THE MAIN IDEA IS THAT THE DEEP COASTAL LOW AND THE PARENT
UPPER LOW WILL REMAIN NEARLY STATIONARY OVER THE MID ATLANTIC
COAST...WHILE STRONG UPPER RIDGING BUILDS OVER THE WRN CONUS BY
FRIDAY...THE UPPER RIDGE IS EXPECTED TO BUILD OVER THE UPPER
MISSISSIPPI VALLEY AND ACROSS THE WRN GREAT LAKES BY NEXT SATURDAY.
THE LONGER RANGE TEMPERATURE GUIDANCE IS SUGGESTING THAT
TEMPERATURES COULD REACH INTO THE LOWER TO MIDDLE 40S BY FRIDAY AND
MIDDLE TO UPPER 40S FOR SATURDAY. HOWEVER...LONGER RANGE
TEMPERATURE GUIDANCE TENDS TO TREND A LITTLE CLOSER TO CLIMATOLOGY
TOWARD THE END OF THE FORECAST PERIOD...SO THE GOING FORECAST OF
MIDDLE TO UPPER 40S FOR NEXT SATURDAY COULD BE ON THE CONSERVATIVE
SIDE...AND WITH THE TYPE OF UPPER LEVEL PATTERN EVOLVING...THERE IS
THE POTENTIAL THAT TEMPERATURES FOR FRIDAY AND SATURDAY COULD VERY
WELL APPROACH OR EXCEED THE 50F MARK.
KREIN
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* SOUTHEAST WINDS AROUND 10 KT TODAY.
* BAND OF MIXED PRECIPITATION EXPECTED MONDAY MORNING. MAY START
AS -FZRA THEN TURN TO SHORT PERIOD OF SLEET/SNOW. IFR CIGS/VSBY
LIKELY FOR A FEW HOUR PERIOD.
KMD
//DISCUSSION...UPDATED 18Z...
NOT MUCH CHANGE IN THINKING ON THE MIXED PRECIPITATION POTENTIAL
MONDAY MORNING...WITH A VERY SLIGHT SLOWING TREND IN THE ABILITY
OF PRECIPITATION TO REACH THE GROUND. 12Z-14Z SEEMS TO BE THE
MOST LIKELY WINDOW FOR A BURST OF WET SNOW/SLEET ACROSS THE
CHICAGO LAND TERMINALS...10Z-12Z FARTHER WEST TOWARDS ROCKFORD.
AS MENTIONED IN EARLIER DISCUSSIONS...PRECIPITATION MAY START AS
LIGHT FREEZING RAIN IF THE INITIAL DRY AIR CAN BE OVERCOME BUT
CURRENT TRENDS SUGGEST THAT THIS WINDOW MAY BE VERY SHORT. THE AIR
MASS IN THE MAIN FORCING SHOULD BE COLDER AND SUPPORT A TRANSITION
TO FROZEN PRECIPITATION. THIS WOULD RESULT IN A BRIEF PERIOD OF
SLUSHY SNOW/SLEET ACCUMULATIONS NO HIGHER THAN 1 INCH AS SURFACE
TEMPERATURES HOVER AROUND THE FREEZING MARK...BUT IT COULD COME
DOWN RATHER QUICKLY. IFR CONDITIONS ARE EXPECTED DURING THIS TIME WITH
POSSIBLE LIFR CONDITIONS FOR A SHORT TIME AS WELL IF THE PRECIP
TYPE TURNS TO ALL SNOW.
AFTERWARDS THE TREND IS TOWARD KEEPING SOME LOWER CIGS AROUND IN
THE MVFR CATEGORY...WITH WINDS SHIFTING TO WESTERLY. PRECIPITATION
TRANSITIONS TO LIGHT RAIN/DRIZZLE AFTER MAIN BAND PUSHES THROUGH.
KMD
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* HIGH CONFIDENCE IN WIND TRENDS.
* MEDIUM-HIGH CONFIDENCE IN A BAND OF MIXED PRECIPITATION
OCCURRING MONDAY MORNING WITH IFR CONDITIONS. MEDIUM CONFIDENCE
IN PROGRESSION OF PRECIP TYPE AND TIMING.
KMD
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
MONDAY NIGHT...VFR. NW WINDS.
TUESDAY...VFR. NW WINDS BECOMING N.
WEDNESDAY...VFR. N WINDS.
THURSDAY...VFR. S WINDS.
FRIDAY...VFR. S WINDS.
SATURDAY...VFR. S WINDS.
MDB
&&
.MARINE...
251 AM CST
HIGH PRESSURE IS CENTERED OVER EASTERN ONTARIO EARLY THIS MORNING
WITH A RIDGE AXIS EXTENDING ACROSS LAKE MICHIGAN. THIS HAS ALLOWED
WINDS TO EASE AND TURN EAST TO NORTHEAST AND WILL ALLOW FOR A SHIFT
TO SOUTHEAST THROUGH THE MORNING. WILL ALLOW THE SMALL CRAFT
ADVISORY TO EXPIRE AS WINDS CONTINUE TO EASE ALLOWING WAVES TO BE ON
A DOWNWARD TREND. WILL CONTINUE WITH A 3-5 OCCASIONAL 7 FT FORECAST.
LOW PRESSURE IS OVER SOUTHERN SASKATCHEWAN AND EASTERN MONTANA AND
WILL BE MOVING EAST ALONG THE CANADIAN BORDER REACHING LAKE SUPERIOR
BY MIDDAY MONDAY. WITH THE HIGH PRESSURE RATHER STRONG THE PRESSURE
GRADIENT BETWEEN IT AND THE LOW WILL BE TIGHTENING THROUGH THE DAY
DESPITE THE LOW NOT BEING TERRIBLY DEEP. AS A RESULT WIND SPEEDS
WILL STEADILY INCREASE TO ABOUT 30 KT ACROSS MOST OF THE LAKE THIS
EVENING WITH SOME 35 KT GALE FORCE GUSTS POSSIBLE ACROSS CENTRAL AND
NORTHERN SECTIONS OVERNIGHT INTO EARLY MONDAY MORNING AS WINDS TURN
MORE SOUTHERLY. WILL ISSUE A SMALL CRAFT ADVISORY FOR MOST OF THE
ILLINOIS NEARSHORE FROM EARLY THIS EVENING THROUGH LATE MONDAY
MORNING AS WINDS AND WAVES COME UP. WINDS WILL THEN TURN
SOUTHWESTERLY MONDAY AFTERNOON AS THE LOW TRACKS TO THE EAST WITH
A SHIFT TO NORTHWEST MONDAY EVENING. COLDER AIR WILL SPREAD IN ON
A FAIRLY STRONG HIGH THAT WILL MOVE INTO THE MID AND UPPER
MISSISSIPPI RIVER VALLEY TUESDAY WHICH WILL ALLOW NORTHWEST WINDS
TO INCREASE EARLY TUESDAY MORNING AND TURN NORTH THROUGH THE DAY.
SPEEDS WILL THEN EASE INTO TUESDAY NIGHT AS THE HIGH MOVES CLOSER
THEN SPREADS ACROSS THE LAKE LATER WEDNESDAY. THE HIGH WILL BE
SLOW TO SHIFT TO THE EAST BUT WINDS WILL TURN WESTERLY AS IT DOES
THURSDAY THEN SOUTHWESTERLY THURSDAY NIGHT. STEADY SOUTHWEST WINDS
ARE THEN EXPECTED INTO THE WEEKEND AS THE HIGH SLOWLY MOVES OFF TO
THE EAST.
MDB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...LMZ740-LMZ741...6 PM SUNDAY TO 10 AM
MONDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
1136 AM CST Sun Dec 7 2014
.UPDATE...
ISSUED AT 1013 AM CST SUN DEC 7 2014
Daytime forecast remains on track, as high clouds overspread the
state from the west.
However, some adjustments have been made to the nighttime trends
ahead of the clipper system. The evening is expected to be dry, so
the PoP`s have been concentrated in the post-midnight hours.
Looking at the forecast soundings across the northern CWA off the
early morning NAM and RAP models, a prominent warm layer around +4
to +5C will be present through the night, so have removed the
mention of snow. The new GFS has a shorter time frame for the warm
layer, cooling it to +2C by morning with ice crystals aloft a bit
more prominent, suggesting more of a rain/snow mixture. Right
now, have mainly gone with a rain/freezing rain mixture north of
I-74 with temperatures in the lower 30s.
&&
.SHORT TERM...(Today)
ISSUED AT 331 AM CST SUN DEC 7 2014
Clouds have cleared out to the south tonight for now, but they are
lingering very close-by. Satellite images already confirm increasing
high clouds from the west. The HRRR is advertising a return of low
clouds from the east-southeast across the eastern half of the area
between 15z/9am and 18z/Noon today, but that seems a bit aggressive
based on the current progression of clouds across Indiana and the
expected wind patterns this morning. Have increased clouds from the
west based on satellite and model consensus, but only trended minor
increases in clouds across the east during the day for now. Will
monitor the movement of low clouds toward our eastern counties for
potential sky cover updates in the short term.
Northeast flow early this morning is expected to evolve to east and
then southeast this afternoon, as high pressure centered over the
Lake Michigan departs farther east across the Great Lakes. The onset
of southeast winds will increase the potential return of low clouds
currently lingering across southern IL.
Temperatures today will only climb about 12-13F above morning lows
due to increasing clouds, with highs topping out in the upper 30s
to low 40s.
&&
.LONG TERM...(Tonight through Saturday)
ISSUED AT 331 AM CST SUN DEC 7 2014
High pressure continues to build into the region, although clouds
continue to dominate the Midwest. Plenty of moisture on sat imagery
obscuring the llvl clouds underneath. Clearing in patches certainly
not anticipated for long as llvl moisture remains trapped by
continuing strong inversion over the area. The dry air aloft is not
coincident with enough turbulence to break up the inversion and
erode the higher RH at roughly 925 mb. This dry air will also be
the first issue for eroding the approaching precip late Sun night
and into Monday. Models maintaining consistency with the last two
runs and continuity with one another with regards to approach and
qpf after midnight tonight and into Monday. A quick front moving
through the area bringing precip after midnight and through the day
Monday so far looks like mostly rain, though the nrn tier of the
state may see a bit more of a rain/snow/wintry mix. Concern remains
whether or not the models are too quick to overcome the dry air
aloft or whether or not the precip may be delayed slightly.
Beyond Monday`s cold front, temps cool briefly, then moderate back
into the 40s for highs through the end of the week. 00z GFS
agreeing with yesterdays 00z ECMWF and backing down from the precip
Wed/Thursday, instead dominating the sfc map with high pressure.
Pops mid week have been removed. Deepening low over the
northeast/east coast causing a bit of a back up across the CONUS as
it is slow to move and the models having some issue with pushing the
new wave inland on the Pacific coast and managing the ridging in the
middle. Seems from Friday and into the weekend the forecast becomes
a bit more problematic in the details as the models work out a
pattern shift again.
&&
.AVIATION...(For the 18Z TAFS through 18Z Monday afternoon)
ISSUED AT 1136 AM CST SUN DEC 7 2014
Main time frame of concern will be after 06Z, as a clipper system
moves in from the west. Ahead of it, VFR conditions to continue
with only high clouds present, and southeast winds gradually
trending more southerly this evening. The clipper is expected to
spread light rain into the KPIA/KBMI areas in the 09-12Z time
frame. Surface temperatures may be cold enough for some brief
freezing rain especially at KBMI, but have held off on mention for
this for now as confidence is not especially high. Further south,
have kept the VCSH mention as there will still be some dry air to
overcome late tonight. Have kept the development of MVFR
conditions later in the period as visibilities lower ahead of the
clipper, and ceilings around 1500 feet or so should overspread the
region late tonight.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Geelhart
SHORT TERM...Shimon
LONG TERM...HJS
AVIATION...Geelhart
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1017 AM CST SUN DEC 7 2014
.SHORT TERM...
427 AM CST
A HIGH AMPLITUDE...PROGRESSIVE UPPER LEVEL PATTERN WILL BRING VERY
CHANGEABLE WEATHER TO THE REGION FOR THE NEXT SEVERAL DAYS...THOUGH
THE MAIN CONCERN WILL BE A WINTRY MIXED PCPN EVENT FOR SUNDAY NIGHT
INTO MONDAY MORNING.
THROUGH MONDAY NIGHT...
FOR THE REMAINDER OF THE NIGHT AND INTO SUNDAY MORNING...CONDITIONS
WILL REMAIN QUIET WITH INCREASING HIGH CLOUD COVER WHICH WILL LIMIT
ANY FURTHER RADIATIVE COOLING AND TEMPERATURES ACROSS THE REGION
SHOULD BOTTOM OUT IN THE LOWER TO MIDDLE 20S...EXCEPT FOR DOWNTOWN
CHICAGO WHICH WILL ONLY DROP TO AROUND 30F. THE REMAINDER OF SUNDAY
SHOULD BE RELATIVELY INNOCUOUS WITH CONTINUED INCREASING MID AND
HIGH LEVEL CLOUD COVER. AS THE CENTER OF A LARGE AREA OF HIGH
PRESSURE SHIFTS FROM THE UPPER GREAT LAKES TO ERN CANADA...A LOW
PRESSURE SYSTEM WILL MOVE OUT OF THE SRN CANADIAN ROCKIES...DRAGGING
A WEAK COLD FRONT INTO THE PLAINS. LOW LEVEL FLOW WILL BECOME MORE
SELY AHEAD OF THE APPROACHING SYSTEM...THOUGH WITH HIGH PRESSURE
RIDGING STILL NOSING SOUTHWEST INTO THE LOWER MISSISSIPPI
VALLEY...EVEN AS TEMPERATURES RISE INTO UPPER 30S...DEWPOINTS WILL
REMAIN RELATIVELY LOW...REMAINING IN THE LOW 20S.
AS THE SYSTEM APPROACHES THE REGION...CONCERNS WILL BECOME PCPN TYPE
AND AMOUNT WITH THE SYSTEM. PREVIOUS MODEL RUNS HAD MAINTAINED A
RELATIVELY DRY ENVIRONMENT AS THE GULF OF MEXICO REMAIN CUT OFF FROM
THE NRN STREAM SYSTEM AND ANY LOW LEVEL MOISTURE TRANSPORT WILL HAVE
TO TAKE A LONG PATH AROUND THE PERIPHERY OF THE SFC RIDGE BEFORE
REACHING INTO THE MIDDLE MISSISSIPPI VALLEY. HOWEVER...THE LATEST
MODEL RUNS ARE INDICATING MORE MOISTURE AVAILABLE TO THE SYSTEM WITH
FORECAST PWATS AROUND 3/4 INCH AND MANY MODELS ARE PAINTING MORE QPF
THAN PREVIOUS RUNS. HAVE SOME CONCERN THAT THE MODELS ARE OVER
FORECASTING MOISTURE CONTENT AND QPF...SO HAVE GONE WITH A MORE
CONSERVATIVE APPROACH TO QPF AMOUNTS THAT WHAT MANY OF THE MODELS
WOULD SUGGEST. HOWEVER...STILL FEEL THAT THERE WILL BE ENOUGH DEEP
LAYER MOISTURE TO PRODUCE MEASURABLE PCPN ACROSS THE REGION. THE
REAL CONCERN WILL BE PCPN TYPE WITH AMOUNTS MORE OF A SECONDARY
CONCERN. THIS IS LARGELY BECAUSE THE GUIDANCE IS INDICATING AN
INTRUSION OF WARM AIR ABOVE A NEARLY SATURATED...BUT BELOW FREEZING
SFC LAYER. THE LATEST RUNS OF THE LOCAL WRFARW...WHICH WAS LARGELY
FOLLOWED FOR THE FINER SCALE DETAILS OF THE PCPN TYPE TREND
INDICATES A RATHER THICK WARM LAYER WITH MAX TEMPS WITHING THE WARM
LAYER OF +3 TO +5C ABOVE A SURFACE BASED INVERSION WITH SFC
TEMPERATURES ARND 30F BY THE TIME THE LEADING EDGE OF THE PCPN MOVES
INTO THE FAR NWRN PORTIONS OF THE CWA. THE LATEST GUIDANCE SUGGESTS
THAT PCPN COULD MOVE INTO THE NWRN PORTIONS OF THE CWA BY ARND
06Z...AND WITH SFC TEMPS OF 30F...BELOW THE DEEP WARM LAYER...PCPN
SHOULD LARGELY BE FREEZING RAIN. THE LEADING EDGE OF THE FREEZING
RAIN SHOULD STEADILY CROSS THE CWA...REACHING THE CHICAGO METRO AREA
DURG THE PREDAWN HOURS. A RATHER STRONG MID LEVEL SHORTWAVE...WITH
700MB OMEGA MAX MOVING ACROSS THE AREA...THERE WILL LIKELY BE A
PERIOD OF SLEET MIXING IN WITH THE FREEZING RAIN DURG THE MORNING
HOURS. PCPN TYPE BECOME A LITTLE MORE COMPLICATED BY LATE MORNING
AND INTO THE AFTERNOON HOURS. MID LEVEL DRY AIR SHOULD MOVE IN
RELATIVELY QUICKLY AS THE HEAVIEST BAND OF PCPN TRACKS FROM WEST TO
EAST ACROSS THE AREA. THE MID LEVEL DRYING COULD OCCUR BEHIND THE
PASSAGE OF THE SFC COLD FRONT. HOWEVER...SINCE THIS SYSTEM IS A
MODIFIED PACIFIC SYSTEM...TEMPERATURES SHOULD NOT DROP OFF QUICKLY
OR SIGNIFICANTLY FOLLOWING THE FROPA...BUT THERE COULD BE A QUICK
BURST OF MODERATE SNOW FOR A SHORT PERIOD WITH THE FROPA AS THE MID
LEVEL WARM LAYER ERODES AND THE ENTIRE COLUMN DROPS BELOW FREEZING.
LATEST THINKING WITH THAT THE ENTIRE CWA SHOULD SEE A LEAST A LIGHT
GLAZING OF FREEZING RAIN...WITH PERHAPS A LIGHT ICE ACCUMULATION
OVER THE NORTHERN PORTIONS OF THE CWA...WHERE QPF AND FORCING WILL
BE STRONGER. ALSO...IT LOOKS LIKE THE ROCKFORD AREA SHOULD HAVE THE
BETTER OPPORTUNITY FOR ACCUMULATING SNOWFALL AS THE THE BEST TIMING
FOR A BURST OF HEAVIER SNOW WILL OCCUR EARLIER IN THE DAY...BEFORE
SFC TEMPS HAVE A CHANCE TO RISE ABOVE FREEZING. BY THE TIME THAT
THE COLD FRONT REACHES THE ERN PORTIONS OF THE CWA...SFC
TEMPERATURES MAY WARM ABOVE FREEZING AND THE CHANCES FOR MUCH
MEASURABLE SNOWFALL WILL BE LOWER....WITH THE FAR SOUTHERN AND SERN
PORTION OF THE CWA...LOCATIONS GENERALLY SOUTH OF THE KANKAKEE RIVER
POSSIBLY ONLY SEEING SOME LIGHT FREEZING RAIN BEFORE BRIEFLY
CHANGING OVER TO SNOW AND THEN EVENTUALLY CHANGING OVER TO ALL RAIN
BY LATE MONDAY MORNING. SO...THE LATEST FORECAST UPDATE WILL
INCLUDE MEASURABLE SNOW NORTH OF THE IL/KANKAKEE RIVERS...WITH THE
I39 CORRIDOR SEEING AS MUCH A 1 INCH OF TOTAL ACCUMULATION...BEFORE
THE WARMER AIR MOVES IN AND MELTS ANY ACCUMULATING SNOW. LOCATIONS
NORTH OF THE RIVERS AND EAST OF I-39 SHOULD ONLY SEE AROUND A HALF
INCH SO SO OF SNOW. THE GREATEST CONCERN WILL BE IMPACTS ON TRAVEL
AS THE FREEZING/FROZEN PCPN WILL BE MOVING ACROSS THE AREA AROUND
THE MORNING RUSH HOURS...AND WITH EVEN LIGHT FREEZING RAIN...THERE
COULD BE TRAVEL DIFFICULTIES. BY LATE MORNING...SFC TEMPS SHOULD
RISE ABOVE FREEZING AND WITH SFC FLOW ONLY VEERING FROM SWLY TO WLY
WITH THE FROPA...LITTLE ACTUAL COOLING IS EXPECTED WITH THE FROPA
AND TEMPERATURES COULD REACH INTO THE UPPER 30S TO AROUND 40F BY
LATE MONDAY AFTERNOON. THE MORE SIGNIFICANT COLD ADVECTION WILL NOT
BEGIN UNTIL THE LATE EVENING HOURS AS THE NEXT SFC HIGH BUILDS
ACROSS THE NRN PLAINS...SETTING UP NWLY FLOW ACROSS THE REGION AND
BY TUESDAY MORNING...TEMPERATURES SHOULD DROP INTO THE MIDDLE TO
UPPER 20S.
KREIN
&&
.LONG TERM...
427 AM CST
TUESDAY THROUGH NEXT SATURDAY...
THE EXTENDED FORECAST PERIOD LOOK TO BE GENERALLY QUIET ACROSS THE
MIDWEST AS DEEP LOW PRESSURE DEVELOPS OF THE MID ATLANTIC
COAST...SLOWING THE PROGRESSION OF THE SFC HIGH ACROSS THE AREA.
THE LATEST LONGER RANGE GUIDANCE SUGGESTS THAT THE CENTER OF THE
HIGH WILL BE SHUNTED INTO SERN CANADA BY THE DEEP LOW OFF THE EAST
COAST...WITH RIDGING EXTENDING THROUGH THE GREAT LAKES AND MIDDLE
MISSISSIPPI VALLEY THROUGH MUCH OF THE WEEK. TEMPERATURES SHOULD
GENERALLY BE SEASONABLE WITH HIGHS IN THE LOWER TO MIDDLE 30S
THROUGH THURSDAY WITH OVERNIGHT LOWS IN THE LOWER TO MIDDLE 20S.
PREVAILING HIGH PRESSURE WILL HELP KEEP THE REGION DRY AND NO
ADDITIONAL PCPN IS LIKELY THROUGH MUCH OF THE WEEK. THE MODELS
CONTINUE TO ADVERTISE A SIGNIFICANT WARMING TREND BY THE END OF THE
WEEK. THE MAIN IDEA IS THAT THE DEEP COASTAL LOW AND THE PARENT
UPPER LOW WILL REMAIN NEARLY STATIONARY OVER THE MID ATLANTIC
COAST...WHILE STRONG UPPER RIDGING BUILDS OVER THE WRN CONUS BY
FRIDAY...THE UPPER RIDGE IS EXPECTED TO BUILD OVER THE UPPER
MISSISSIPPI VALLEY AND ACROSS THE WRN GREAT LAKES BY NEXT SATURDAY.
THE LONGER RANGE TEMPERATURE GUIDANCE IS SUGGESTING THAT
TEMPERATURES COULD REACH INTO THE LOWER TO MIDDLE 40S BY FRIDAY AND
MIDDLE TO UPPER 40S FOR SATURDAY. HOWEVER...LONGER RANGE
TEMPERATURE GUIDANCE TENDS TO TREND A LITTLE CLOSER TO CLIMATOLOGY
TOWARD THE END OF THE FORECAST PERIOD...SO THE GOING FORECAST OF
MIDDLE TO UPPER 40S FOR NEXT SATURDAY COULD BE ON THE CONSERVATIVE
SIDE...AND WITH THE TYPE OF UPPER LEVEL PATTERN EVOLVING...THERE IS
THE POTENTIAL THAT TEMPERATURES FOR FRIDAY AND SATURDAY COULD VERY
WELL APPROACH OR EXCEED THE 50F MARK.
KREIN
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* SOUTHEAST WINDS AROUND 10 KT TODAY.
* BAND OF MIXED PRECIPITATION EXPECTED MONDAY MORNING. MAY START
AS -FZRA THEN TURN TO SHORT PERIOD OF SLEET/SNOW. IFR CIGS/VSBY
POSSIBLE FOR A FEW HOUR PERIOD.
KMD
//DISCUSSION...UPDATED 12Z...
HIGH PRESSURE RIDGING IS ACROSS THE AREA THIS MORNING BUT WILL BE
SHIFTING TO THE EAST. THIS WILL RESULT IN STEADY SOUTHEAST WINDS
THROUGH THE DAY WITH VFR CONDITIONS. LOW PRESSURE WILL MOVE ACROSS
THE AREA MONDAY MORNING BRINGING A PERIOD OF MIXED PRECIPITATION
WITH IT. A FEW HOUR PERIOD IS EXPECTED TO BEGIN TOWARD 09Z OUT
NEAR RFD AND TOWARD 11Z IN THE CHICAGO AREA. THE DETAILS REMAIN IN
FLUX BUT THE LATEST THINKING IS THAT PRECIPITATION WILL START OUT
AS A SHORT PERIOD OF FREEZING RAIN THEN TRANSITION TO A MIX OF
SLEET AND SNOW FOR A 1-3 HOUR PERIOD. FORCING IS STRONG FOR A
SHORT TIME SO IT IS POSSIBLE THAT A PERIOD OF MODERATE SNOW OCCURS
LEADING TO SOME SLUSHY ACCUMULATION. PRECIPITATION WILL INITIALLY
BE FIGHTING A LAYER OF DRY AIR SO ONSET COULD BE DELAYED AND THIS
MAY ALSO AFFECT THE PROGRESSION OF PRECIP TYPES. PRECIP INTENSITY
WILL QUICKLY DIMINISH MID TO LATE MORNING MONDAY WITH LIGHT RAIN
OR DRIZZLE POSSIBLE AS TEMPERATURES WARM ABOVE FREEZING. A PERIOD
OF IFR CIGS IS EXPECTED PROVIDED DECENT PRECIP OCCURS AND IFR VSBY
WOULD BE LIKELY IF A SHORT PERIOD OF MAINLY SNOW CAN OCCUR. BE
SURE TO CHECK BACK FOR FURTHER UPDATES...
MDB
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* HIGH CONFIDENCE IN WIND TRENDS.
* MEDIUM-HIGH CONFIDENCE IN A BAND OF MIXED PRECIPITATION
OCCURRING MONDAY MORNING. MEDIUM CONFIDENCE IN PROGRESSION OF
PRECIP TYPE AND TIMING.
KMD
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
MONDAY NIGHT...VFR. NW WINDS.
TUESDAY...VFR. NW WINDS BECOMING N.
WEDNESDAY...VFR. N WINDS.
THURSDAY...VFR. S WINDS.
FRIDAY...VFR. S WINDS.
SATURDAY...VFR. S WINDS.
MDB
&&
.MARINE...
251 AM CST
HIGH PRESSURE IS CENTERED OVER EASTERN ONTARIO EARLY THIS MORNING
WITH A RIDGE AXIS EXTENDING ACROSS LAKE MICHIGAN. THIS HAS ALLOWED
WINDS TO EASE AND TURN EAST TO NORTHEAST AND WILL ALLOW FOR A SHIFT
TO SOUTHEAST THROUGH THE MORNING. WILL ALLOW THE SMALL CRAFT
ADVISORY TO EXPIRE AS WINDS CONTINUE TO EASE ALLOWING WAVES TO BE ON
A DOWNWARD TREND. WILL CONTINUE WITH A 3-5 OCCASIONAL 7 FT FORECAST.
LOW PRESSURE IS OVER SOUTHERN SASKATCHEWAN AND EASTERN MONTANA AND
WILL BE MOVING EAST ALONG THE CANADIAN BORDER REACHING LAKE SUPERIOR
BY MIDDAY MONDAY. WITH THE HIGH PRESSURE RATHER STRONG THE PRESSURE
GRADIENT BETWEEN IT AND THE LOW WILL BE TIGHTENING THROUGH THE DAY
DESPITE THE LOW NOT BEING TERRIBLY DEEP. AS A RESULT WIND SPEEDS
WILL STEADILY INCREASE TO ABOUT 30 KT ACROSS MOST OF THE LAKE THIS
EVENING WITH SOME 35 KT GALE FORCE GUSTS POSSIBLE ACROSS CENTRAL AND
NORTHERN SECTIONS OVERNIGHT INTO EARLY MONDAY MORNING AS WINDS TURN
MORE SOUTHERLY. WILL ISSUE A SMALL CRAFT ADVISORY FOR MOST OF THE
ILLINOIS NEARSHORE FROM EARLY THIS EVENING THROUGH LATE MONDAY
MORNING AS WINDS AND WAVES COME UP. WINDS WILL THEN TURN
SOUTHWESTERLY MONDAY AFTERNOON AS THE LOW TRACKS TO THE EAST WITH
A SHIFT TO NORTHWEST MONDAY EVENING. COLDER AIR WILL SPREAD IN ON
A FAIRLY STRONG HIGH THAT WILL MOVE INTO THE MID AND UPPER
MISSISSIPPI RIVER VALLEY TUESDAY WHICH WILL ALLOW NORTHWEST WINDS
TO INCREASE EARLY TUESDAY MORNING AND TURN NORTH THROUGH THE DAY.
SPEEDS WILL THEN EASE INTO TUESDAY NIGHT AS THE HIGH MOVES CLOSER
THEN SPREADS ACROSS THE LAKE LATER WEDNESDAY. THE HIGH WILL BE
SLOW TO SHIFT TO THE EAST BUT WINDS WILL TURN WESTERLY AS IT DOES
THURSDAY THEN SOUTHWESTERLY THURSDAY NIGHT. STEADY SOUTHWEST WINDS
ARE THEN EXPECTED INTO THE WEEKEND AS THE HIGH SLOWLY MOVES OFF TO
THE EAST.
MDB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...LMZ740-LMZ741...6 PM SUNDAY TO 10 AM
MONDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
1014 AM CST Sun Dec 7 2014
.UPDATE...
ISSUED AT 1013 AM CST SUN DEC 7 2014
Daytime forecast remains on track, as high clouds overspread the
state from the west.
However, some adjustments have been made to the nighttime trends
ahead of the clipper system. The evening is expected to be dry, so
the PoP`s have been concentrated in the post-midnight hours.
Looking at the forecast soundings across the northern CWA off the
early morning NAM and RAP models, a prominent warm layer around +4
to +5C will be present through the night, so have removed the
mention of snow. The new GFS has a shorter time frame for the warm
layer, cooling it to +2C by morning with ice crystals aloft a bit
more prominent, suggesting more of a rain/snow mixture. Right
now, have mainly gone with a rain/freezing rain mixture north of
I-74 with temperatures in the lower 30s.
&&
.SHORT TERM...(Today)
ISSUED AT 331 AM CST SUN DEC 7 2014
Clouds have cleared out to the south tonight for now, but they are
lingering very close-by. Satellite images already confirm increasing
high clouds from the west. The HRRR is advertising a return of low
clouds from the east-southeast across the eastern half of the area
between 15z/9am and 18z/Noon today, but that seems a bit aggressive
based on the current progression of clouds across Indiana and the
expected wind patterns this morning. Have increased clouds from the
west based on satellite and model consensus, but only trended minor
increases in clouds across the east during the day for now. Will
monitor the movement of low clouds toward our eastern counties for
potential sky cover updates in the short term.
Northeast flow early this morning is expected to evolve to east and
then southeast this afternoon, as high pressure centered over the
Lake Michigan departs farther east across the Great Lakes. The onset
of southeast winds will increase the potential return of low clouds
currently lingering across southern IL.
Temperatures today will only climb about 12-13F above morning lows
due to increasing clouds, with highs topping out in the upper 30s
to low 40s.
&&
.LONG TERM...(Tonight through Saturday)
ISSUED AT 331 AM CST SUN DEC 7 2014
High pressure continues to build into the region, although clouds
continue to dominate the Midwest. Plenty of moisture on sat imagery
obscuring the llvl clouds underneath. Clearing in patches certainly
not anticipated for long as llvl moisture remains trapped by
continuing strong inversion over the area. The dry air aloft is not
coincident with enough turbulence to break up the inversion and
erode the higher RH at roughly 925 mb. This dry air will also be
the first issue for eroding the approaching precip late Sun night
and into Monday. Models maintaining consistency with the last two
runs and continuity with one another with regards to approach and
qpf after midnight tonight and into Monday. A quick front moving
through the area bringing precip after midnight and through the day
Monday so far looks like mostly rain, though the nrn tier of the
state may see a bit more of a rain/snow/wintry mix. Concern remains
whether or not the models are too quick to overcome the dry air
aloft or whether or not the precip may be delayed slightly.
Beyond Monday`s cold front, temps cool briefly, then moderate back
into the 40s for highs through the end of the week. 00z GFS
agreeing with yesterdays 00z ECMWF and backing down from the precip
Wed/Thursday, instead dominating the sfc map with high pressure.
Pops mid week have been removed. Deepening low over the
northeast/east coast causing a bit of a back up across the CONUS as
it is slow to move and the models having some issue with pushing the
new wave inland on the Pacific coast and managing the ridging in the
middle. Seems from Friday and into the weekend the forecast becomes
a bit more problematic in the details as the models work out a
pattern shift again.
&&
.AVIATION...(For the 12Z TAFS through 12Z Monday morning)
ISSUED AT 554 AM CST SUN DEC 7 2014
High pressure centered over lower Michigan and extending SW into
IL will slide east today. That movement will cause our surface
winds to shift from NE to SE by this afternoon, while increasing
to 10-14kt. High clouds will blanket the entire state today, with
low clouds lurking just south of our forecast area already at
12z/6am. As winds shift to SE, that cloud mass will eventually
gain momentum toward the terminal sites. HRRR indicates that SPI
and DEC will have the higher potential of seeing a return of MVFR
clouds after 22z/4pm, with the clouds eventually advancing all the
way north to PIA/BMI/CMI during the evening. The initial push of
moisture may have breaks in the ceiling per the latest HRRR, so we
delayed the persistent low clouds until later evening when light
rain will begin to develop from NW to SE ahead of an approaching
warm front and low pressure system. While any light rain could
change to freezing rain late in this TAF period, we did not
include FZRA with this issuance. We only mentioned VCSH after
midnight for now.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Geelhart
SHORT TERM...Shimon
LONG TERM...HJS
AVIATION...Shimon
AREA FORECAST DISCUSSION
NWS GOODLAND KS
400 PM MST SUN DEC 7 2014
.SHORT TERM...(THIS AFTERNOON THROUGH MONDAY)
ISSUED AT 212 PM MST SUN DEC 7 2014
LATEST WV IMAGERY AND RAP ANALYSIS SHOW RIDGING BUILDING ACROSS
WESTERN US...WITH TROUGH CENTERED OVER NORTH DAKOTA AND ITS AXIS
EXTENDING ACROSS EASTERN NE/KS INTO THE SOUTHERN PLAINS. AT THE
SURFACE LOW PRESSURE HAS BUILD ACROSS NORTHERN COLORADO WITH A
WEAK SURFACE TROUGH OVER OUR CWA. STRATUS FOG HAS ERODED AND
CLEAR SKIES/DOWNSLOPE FLOW HAS LED TO TEMPS WARMING INTO THE
MIDDLE 60S ACROSS NW KANSAS AND PARTS OF NORTHEAST COLORADO.
SHORTWAVE RIDGE WILL TRANSITION OVER THE CWA TONIGHT AND MONDAY
WITH DRY CONDITIONS AND MILD TEMPS PERSISTING. THERE IS A WEAK
SHORTWAVE THAT MIGHT BRING SLIGHTLY COOLER TEMPS ALOFT AND HIGH
CLOUD COVER MONDAY AFTERNOON...OTHERWISE WE SHOULD SEE LITTLE
CHANGE IN SENSIBLE WEATHER OVER CWA. GOOD RADIATIONAL CONDITIONS
SHOULD BE IN PLACE AND DEPENDING ON HOW LOW THE TD VALUES WILL
DROP WE COULD SEE OVERNIGHT LOWS IN THE UPPER TEENS TO LOWER 20S.
MET GUIDANCE WAS HINTING AT LIGHT FOG DEVELOPMENT...HOWEVER ALL
OTHER 2M AND STATISTICAL GUIDANCE IS NOT SHOWING THIS...AND WITH
DRY AIR ADVECTING FROM THE WEST TO SOUTHWEST I DECIDED AGAINST FOG
MENTION. DESPITE SLIGHTLY COOLER TEMPS ALOFT MONDAY...THE TREND
HAS BEEN FOR MOST GUIDANCE TO HAVE A COOL BIAS WITH GOOD WARMING
OVER THE LAST FEW DAYS. CONSIDERING THESE BIASES I WOULD STILL
EXPECT DAYTIME HIGHS MONDAY TO BE AROUND 60 FOR MOST OF THE
CWA...WHICH IS A LITTLE LOWER THAN WHAT WE SAW TODAY.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 212 PM MST SUN DEC 7 2014
FOR THE EXTENDED PERIOD...BROAD H5 RIDGE WILL BE IN PLACE OVER THE
WESTERN HALF OF THE COUNTRY FOR MUCH OF THE UPCOMING WEEK. BY THE
TIME GOING INTO THE UPCOMING WEEKEND THOUGH...MODELS DO SHIFT THIS
RIDGE MORE EASTWARD AS A TROUGH APPROACHES THE WEST COAST...INTO THE
ROCKIES ON SATURDAY AND THEN OUT OVER THE CENTRAL/SOUTHERN PLAINS BY
NEXT SUNDAY AS A CUTOFF UPPER LOW. THE LATEST GFS/ECMWF RUNS DO
DIFFER ON TRACK AND PLACEMENT OF THIS SYSTEM AND WILL AFFECT
PRECIPITATION POTENTIAL FOR THE FORECAST AREA.
WITH THE LARGE AREA OF HIGH PRESSURE EXPECTED FOR MUCH OF THE
WEEK...THE CWA WILL BE LOOKING AT HIGH TEMPS 10-15 DEGREES ABOVE
NORMAL AND OVERNIGHT LOWS 5-10 DEGREES ABOVE NORMAL. 925MB TEMPS
RANGING FROM +10C TO +15C THRU THE WEEK BEFORE THE TROUGH ARRIVES
SATURDAY NIGHT/SUNDAY...THE AREA WILL SEE HIGHS 55-60F AND OVERNIGHT
LOWS IN THE MID 20S TO LOW 30S.
PRECIPITATION CHANCES FOR THE UPCOMING WEEK WILL BE NEAR ZERO AS A
RESULT OF HIGH PRESSURE OVER THE AREA. THERE IS A WEAK 700 MB
SHORTWAVE MOVING OFF THE ROCKIES TUESDAY NIGHT INTO WEDNESDAY THAT
TRAVERSES THE REGION. MODERATE 1000-500MB RH VALUES WILL ACCOMPANY
THE PASSAGE OF THIS TROUGH...BUT WITH SURFACE HIGH PRESSURE OVER
AREA...LOW LEVEL AIRMASS WILL BE TOO DRY SO HAVE CONTINUED PREVIOUS
FORECAST THINKING OF JUST MID LEVEL CLOUD COVER WITH THIS ONLY. THE
ONLY CHANCE WILL BE OVER THE UPCOMING WEEKEND WITH THE PASSAGE OF
THE UPPER LOW/TROUGH. LATEST GFS HAS THIS SYSTEM COMING OVER THE
AREA OFF THE ROCKIES...WHILE THE ECMWF HAS THIS SYSTEM DROPPING
OVER TEXAS. THIS WILL ALLOW FOR SYSTEM TO GRAB AMPLE MOISTURE TO
PRODUCE SOME PRECIP...WHILE THE GFS IS ALMOST DRY. WHILE THE BULK OF
THE ECMWF SCENARIO WILL REMAIN SOUTH OF THE CWA...STILL THINK SOME
OF THIS WILL IMPACT THE CWA SO HAVE KEPT IN UP TO CHANCE POPS FOR
LIGHT RAIN/SNOW. LOOKING FOR ANY LIGHT SNOW AT NIGHT SATURDAY INTO
SUNDAY MORNING...AND ANY LIGHT RAIN DURING THE DAY. THE CWA AFFECTED
WITH ANY OVERNIGHT LIGHT SNOW SHOULD BE LIGHT ON THE ORDER OF A
COUPLE TENTHS RIGHT NOW.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 400 PM MST SUN DEC 7 2014
FOR KGLD AND KMCK...VFR THROUGH THE PERIOD. LIGHT NORTHWEST WINDS
AT TAF ISSUANCE FORECAST TO BACK TO THE WEST AROUND 08Z THEN
SOUTHWEST AROUND 19Z...SPEEDS UNDER 10KTS. BY 23Z LIGHT/VARIABLE
WINDS EXPECTED. FAIR WEATHER CU POSSIBLE AFTER 19Z MONDAY
OTHERWISE SOME SLIGHT INCREASE IN HIGH CLOUDS MOVING IN FROM THE
NORTHWEST.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...JN
AVIATION...99
AREA FORECAST DISCUSSION...CORRECTED
NWS GOODLAND KS
212 PM MST SUN DEC 7 2014
.SHORT TERM...(THIS AFTERNOON THROUGH MONDAY)
ISSUED AT 212 PM MST SUN DEC 7 2014
LATEST WV IMAGERY AND RAP ANALYSIS SHOW RIDGING BUILDING ACROSS
WESTERN US...WITH TROUGH CENTERED OVER NORTH DAKOTA AND ITS AXIS
EXTENDING ACROSS EASTERN NE/KS INTO THE SOUTHERN PLAINS. AT THE
SURFACE LOW PRESSURE HAS BUILD ACROSS NORTHERN COLORADO WITH A
WEAK SURFACE TROUGH OVER OUR CWA. STRATUS FOG HAS ERODED AND
CLEAR SKIES/DOWNSLOPE FLOW HAS LED TO TEMPS WARMING INTO THE
MIDDLE 60S ACROSS NW KANSAS AND PARTS OF NORTHEAST COLORADO.
SHORTWAVE RIDGE WILL TRANSITION OVER THE CWA TONIGHT AND MONDAY
WITH DRY CONDITIONS AND MILD TEMPS PERSISTING. THERE IS A WEAK
SHORTWAVE THAT MIGHT BRING SLIGHTLY COOLER TEMPS ALOFT AND HIGH
CLOUD COVER MONDAY AFTERNOON...OTHERWISE WE SHOULD SEE LITTLE
CHANGE IN SENSIBLE WEATHER OVER CWA. GOOD RADIATIONAL CONDITIONS
SHOULD BE IN PLACE AND DEPENDING ON HOW LOW THE TD VALUES WILL
DROP WE COULD SEE OVERNIGHT LOWS IN THE UPPER TEENS TO LOWER 20S.
MET GUIDANCE WAS HINTING AT LIGHT FOG DEVELOPMENT...HOWEVER ALL
OTHER 2M AND STATISTICAL GUIDANCE IS NOT SHOWING THIS...AND WITH
DRY AIR ADVECTING FROM THE WEST TO SOUTHWEST I DECIDED AGAINST FOG
MENTION. DESPITE SLIGHTLY COOLER TEMPS ALOFT MONDAY...THE TREND
HAS BEEN FOR MOST GUIDANCE TO HAVE A COOL BIAS WITH GOOD WARMING
OVER THE LAST FEW DAYS. CONSIDERING THESE BIASES I WOULD STILL
EXPECT DAYTIME HIGHS MONDAY TO BE AROUND 60 FOR MOST OF THE
CWA...WHICH IS A LITTLE LOWER THAN WHAT WE SAW TODAY.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 212 PM MST SUN DEC 7 2014
FOR THE EXTENDED PERIOD...BROAD H5 RIDGE WILL BE IN PLACE OVER THE
WESTERN HALF OF THE COUNTRY FOR MUCH OF THE UPCOMING WEEK. BY THE
TIME GOING INTO THE UPCOMING WEEKEND THOUGH...MODELS DO SHIFT THIS
RIDGE MORE EASTWARD AS A TROUGH APPROACHES THE WEST COAST...INTO THE
ROCKIES ON SATURDAY AND THEN OUT OVER THE CENTRAL/SOUTHERN PLAINS BY
NEXT SUNDAY AS A CUTOFF UPPER LOW. THE LATEST GFS/ECMWF RUNS DO
DIFFER ON TRACK AND PLACEMENT OF THIS SYSTEM AND WILL AFFECT
PRECIPITATION POTENTIAL FOR THE FORECAST AREA.
WITH THE LARGE AREA OF HIGH PRESSURE EXPECTED FOR MUCH OF THE
WEEK...THE CWA WILL BE LOOKING AT HIGH TEMPS 10-15 DEGREES ABOVE
NORMAL AND OVERNIGHT LOWS 5-10 DEGREES ABOVE NORMAL. 925MB TEMPS
RANGING FROM +10C TO +15C THRU THE WEEK BEFORE THE TROUGH ARRIVES
SATURDAY NIGHT/SUNDAY...THE AREA WILL SEE HIGHS 55-60F AND OVERNIGHT
LOWS IN THE MID 20S TO LOW 30S.
PRECIPITATION CHANCES FOR THE UPCOMING WEEK WILL BE NEAR ZERO AS A
RESULT OF HIGH PRESSURE OVER THE AREA. THERE IS A WEAK 700 MB
SHORTWAVE MOVING OFF THE ROCKIES TUESDAY NIGHT INTO WEDNESDAY THAT
TRAVERSES THE REGION. MODERATE 1000-500MB RH VALUES WILL ACCOMPANY
THE PASSAGE OF THIS TROUGH...BUT WITH SURFACE HIGH PRESSURE OVER
AREA...LOW LEVEL AIRMASS WILL BE TOO DRY SO HAVE CONTINUED PREVIOUS
FORECAST THINKING OF JUST MID LEVEL CLOUD COVER WITH THIS ONLY. THE
ONLY CHANCE WILL BE OVER THE UPCOMING WEEKEND WITH THE PASSAGE OF
THE UPPER LOW/TROUGH. LATEST GFS HAS THIS SYSTEM COMING OVER THE
AREA OFF THE ROCKIES...WHILE THE ECMWF HAS THIS SYSTEM DROPPING
OVER TEXAS. THIS WILL ALLOW FOR SYSTEM TO GRAB AMPLE MOISTURE TO
PRODUCE SOME PRECIP...WHILE THE GFS IS ALMOST DRY. WHILE THE BULK OF
THE ECMWF SCENARIO WILL REMAIN SOUTH OF THE CWA...STILL THINK SOME
OF THIS WILL IMPACT THE CWA SO HAVE KEPT IN UP TO CHANCE POPS FOR
LIGHT RAIN/SNOW. LOOKING FOR ANY LIGHT SNOW AT NIGHT SATURDAY INTO
SUNDAY MORNING...AND ANY LIGHT RAIN DURING THE DAY. THE CWA AFFECTED
WITH ANY OVERNIGHT LIGHT SNOW SHOULD BE LIGHT ON THE ORDER OF A
COUPLE TENTHS RIGHT NOW.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1039 AM MST SUN DEC 7 2014
MORNING FOG/STRATUS HAVE SHIFTED EAST OF KMCK...AND VFR CONDITIONS
SHOULD PREVAIL THROUGH THE VALID TAF PERIOD AT BOTH KGLD AND
KMCK. MET GUIDANCE SHOWS A BRIEF PERIOD OF 3-5SM VIS
OVERNIGHT...AND WHILE GOOD RADIATIONAL CONDITIONS WILL BE IN PLACE
PREVAILING WIND DIRECTION WILL TEND TO ADVECT DRY AIR INTO THE THE
AREA OF BOTH TAF SITES. OTHER GUIDANCE IS SHOWING PREVAILING VFR
CONDITIONS...SO I AM NOT GOING TO BUY INTO LOWER VIS AT THIS TIME.
WEST TO SOUTHWEST WINDS WILL GUST AROUND 20KT AT BOTH TAF SITES
THIS AFTERNOON...OTHERWISE WINDS SHOULD REMAIN BELOW 12KT THROUGH
THE REST OF THE TAF PERIOD.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...JN
AVIATION...DR
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1108 AM CST SUN DEC 7 2014
...UPDATE TO AVIATION...
.SYNOPSIS...
ISSUED AT 858 AM CST SUN DEC 7 2014
WV IMAGERY AND 12Z UPPER AIR ANALYSIS INDICATE AN UPPER LEVEL TROUGH
OF LOW PRESSURE TRANSITIONING EASTWARD ACROSS THE NORTHERN PLAINS.
MEANWHILE, A SECONDARY UPPER LEVEL SHORTWAVE IS MOVING EAST OUT OF
THE SOUTHERN ROCKIES INTO THE WESTERN HIGH PLAINS. NEAR THE SURFACE,
A WEAK LEE SIDE TROUGH OF LOW PRESSURE IS LOCATED NEAR AND ALONG THE
KANSAS AND COLORADO BORDER.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 202 AM CST SUN DEC 7 2014
WATER VAPOR LOOP INDICATING THE THE LATEST RAP AND NAM WERE DOING
A DECENT JOB ON THE TRACK OF AN UPPER LEVEL TROUGH AS IT MOVED
ACROSS EASTERN COLORADO EARLIER THIS MORNING. BOTH THE RAP AND NAM
MOVE THIS UPPER LEVEL FEATURE ACROSS WESTERN KANSAS BETWEEN 09Z
AND 15Z SUNDAY. MODEL SOUNDINGS INDICATING MOISTURE AHEAD OF THIS
UPPER LEVEL FEATURE WILL BE AT OR ABOVE THE 800MB LEVEL. IN
ADDITION TO THIS AREA OF MOISTURE THE SURFACE TO 1000 TO 2000FT
AGL LAYER WILL ALSO BE SATURATED EARLY THIS MORNING WITH THE
DEEPER LOW LEVEL MOISTURE APPEARING TO BE NEAR AND EAST OF HIGHWAY
283. BASED ON MODEL SOUNDINGS THE DEPTH OF THE LOW LEVEL MOISTURE
DOES NOT APPEAR DEEP ENOUGH TO SUPPORT DRIZZLE, HOWEVER WEAK LIFT
AHEAD OF THE UPPER LEVEL TROUGH MAY GIVE RISE TO SOME SPRINKLES OR
EVEN A BRIEF RAIN SHOWER...MAINLY IN NORTH CENTRAL AND SOUTH
CENTRAL KANSAS. WILL THEREFORE RETAIN SMALL CHANCE FOR
PRECIPITATION EARLY THIS MORNING EAST OF HIGHWAY 283.
WIDESPREAD STATUS AND FOG WILL BE LIKELY EARLY THIS MORNING. AT
THIS TIME THE AREA FAVORABLE FOR THE LOWER VISIBILITIES WILL BE
EAST OF HIGHWAY 83 THROUGH 15Z SUNDAY GIVEN THE LOW LEVEL MOISTURE
PROFILES AND BETTER UPSLOPE FLOW. BASED ON THE LATEST RAP AND HRRR
ALONG WITH MOST RECENT SURFACE OBSERVATIONS THE CURRENT DENSE FOG
ADVISORY HAS A GOOD HANDLE ON THIS SO NO MAJOR ADJUSTMENTS PLANNED
THIS MORNING. WILL CONTINUE TO MONITOR THIS AND ADJUST
ACCORDINGLY.
SUBSIDENCE DEVELOPING BEHIND THE UPPER LEVEL TROUGH DURING THE
LATE MORNING AND EARLY AFTERNOON WILL ALLOW FOR SOME AFTERNOON
SUNSHINE TO DEVELOP. AT THIS TIME CONFIDENCE IS NOT HIGH ON HOW
QUICKLY THE SKIES WILL CLEAR EAST OF DODGE CITY, HOWEVER BASED ON
THE NAM AND RAP TIMING OF THE CLEARING TREND FROM WEST TO EAST
ALONG WITH THE 850MB TEMPERATURES AT 21Z SUNDAY AND 00Z MONDAY THE
PREVIOUS FORECAST STILL LOOKS ON TRACK. WILL CONTINUE TO FAVOR THE
WARMER MAV GUIDANCE FOR HIGHS WEST OF ROUGHLY HIGHWAY 83 WHERE
MORE SUN THAN CLOUDS ARE EXPECTED DURING THE AFTERNOON. FURTHER
EAST FAVORED THE COOLER MET.
A SURFACE BOUNDARY WILL DROP SOUTH ACROSS WESTERN KANSAS LATE THIS
AFTERNOON AND EARLY TONIGHT. AS THIS BOUNDARY PASSES A
NORTHWESTERLY FLOW WILL DEVELOP AND DRIER AIR WILL RETURN TO
WESTERN KANSAS IN THE 0-1KM AGL LEVEL. BASED ON WESTERLY WINDS AT
10 KNOTS OR LESS AND DRIER AIR ADVECTING INTO WESTERN KANSAS WILL
THE PREVIOUS FORECAST WITH LOWS IN THE UPPER 20S TO LOWER 30S
STILL LOOKS ON TRACK.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 353 AM CST SUN DEC 7 2014
THE REST OF THE EXTENDED PERIOD IS SIMILAR TO THE LAST SEVERAL DAYS
AS FAR AS TEMPERATURES ARE CONCERNED, WITH RELATIVELY LOW IMPACT
SYNOPTIC SCALE WAVES EVERY COUPLE OF DAYS. DRIER AIR ALOFT WILL
INFLUENCE THE AREA MONDAY ON THE HEELS OF THE EXITING UPPER JET.
SUNNY SKY AND LIGHT SURFACE WINDS WILL LEAD TO TEMPERATURES MAINLY
INFLUENCED BY DIURNAL INSOLATION, WHILE EASTERLY SURFACE WINDS
DEVELOP OVERNIGHT INTO EARLY TUESDAY. SOME FOG OR STRATUS COULD
DEVELOP IN THE FAR WESTERN SECTIONS NEAR THE COLORADO LINE, BUT THIS
WOULD BE FAIRLY LIMITED AS OPPOSED THE MORE WIDESPREAD FOG OF LAST
NIGHT. THE ECMWF IS MORE AGGRESSIVE THAN THE GFS IN DEVELOPING RAIN
SHOWERS WITH THE POSITIVELY TILTED WAVE ON WEDNESDAY. FOR NOW LOW
PROBABILITIES EXIST FOR CENTRAL KANSAS WHERE BETTER MOISTURE SHOULD
BE PRESENT AS WELL AS BETTER STRETCHING DEFORMATION WITH THIS
PATTERN.
CONSIDERABLE UNCERTAINTY IN MESOSCALE DETAIL FOLLOWS BEYOND
WEDNESDAY AS THE ECMWF AND GFS BOTH AGREE ON AN INCOMING SYNOPTIC
LOW APPROACHING THE REGION WITH SOUTHERLY BOUNDARY LAYER WINDS. THE
DIFFERENCES EXIST IT A FAR MORE MOIST, STRATUS AND FOG TYPE PATTERN
OF THE EC AND MORE DRY BOUNDARY LAYER OR WESTERN KS WITH THE GFS
WHICH CAN ALSO MAKE LARGE DIFFERENCES IN EXPECTED TEMPERATURES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1100 AM CST SUN DEC 7 2014
IFR CIGS WILL LINGER IN THE VICINITY OF KDDC AND KHYS EARLY THIS
AFTERNOON AS LOW LEVEL STRATUS SLOWLY ERODES WEST TO EAST.
OTHERWISE, VFR CONDTIONS WILL RETURN/PREVAIL AT ALL TAF SITES
THROUGH EARLY MONDAY MORNING. SOUTHWESTERLY WINDS WILL TURN WEST
TO NORTHWESTERLY 5 TO 10KT EARLY THIS EVENING AS A WEAK LEE SIDE
TROUGH OF LOW PRESSURE MOVES EAST INTO WESTERN KANSAS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 58 31 58 32 / 30 0 0 0
GCK 60 28 58 30 / 10 0 0 0
EHA 63 33 60 36 / 10 0 0 0
LBL 60 30 59 31 / 10 0 0 0
HYS 55 29 56 28 / 20 0 0 0
P28 57 33 58 33 / 30 0 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...JJOHNSON
SHORT TERM...BURGERT
LONG TERM...RUSSELL
AVIATION...JJOHNSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
342 PM EST SUN DEC 7 2014
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 338 PM EST SUN DEC 7 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A WELL-DEFINED SHORTWAVE
MOVING ACROSS MT EARLY THIS MORNING. THIS WAVE WILL BE THE FEATURE
OF INTEREST IN THE SHORT TERM AS IT SHIFTS E...REACHING THE UPPER
GREAT LAKES MON. AT THE SFC...SHORTWAVE WAS SUPPORTING LOW PRES OVER
SRN SASKATCHEWAN. TO THE E...HIGH PRES CENTER HAS SLIPPED E OF LAKE
SUPERIOR/UPPER MI. STRONG WAA/ISENTROPIC ASCENT REGIME BTWN THE
SHORTWAVE AND DEPARTING HIGH PRES HAS LED TO QUITE A BIT OF MID
LEVEL CLOUDINESS SPREADING INTO UPPER MI DURING THE NIGHT. RADARS
ARE ALSO SHOWING RETURNS...BUT SO FAR...THE FARTHEST S ANY -SN HAS
BEEN REPORTED IN OBS IS AT THUNDER BAY ONTARIO AS DRY AIR NOTED
BELOW 750MB ON 00Z KINL SOUNDING IS WORKING TO LIMIT SOUTHWARD
EXTENT OF -SN REACHING THE GROUND.
TODAY...SHORTWAVE OVER MT WILL MOVE TO THE ERN DAKOTAS WITH
ASSOCIATED SFC LOW REACHING FAR SE MANITOBA BY EVENING. STRONG
WAA/ISENTROPIC ASCENT WHICH IS CURRENTLY FOCUSED INTO NRN MN WILL
SHIFT E TODAY...BUT MODELS CONTINUE TO INDICATE THAT LOW-LEVELS WILL
FAIL TO MOISTEN ACROSS UPPER MI DUE TO A PERSISTENT FEED OF
LOW-LEVEL DRY AIR FROM DEPARTING HIGH PRES. TO THE W...AXIS OF
850-700MB MOISTURE TRANSPORT AND LOWERING CONDENSATION PRES DEFICITS
AHEAD OF SHORTWAVE REMAINS JUST W OF THE AREA THRU THE AFTN. SO...
NOT EXPECTING ANY PCPN DURING THE DAYLIGHT HRS TODAY. TEMPS SHOULD
REACH THE UPPER 20S/LWR 30S.
TONIGHT...AS RIBBON OF 850-700MB MOISTURE TRANSPORT...ISENTROPIC
ASCENT ENHANCED BY 850MB WINDS OF 40-50KT AND DEEP LAYER QVECTOR
CONVERGENCE IN ADVANCE OF APPROACHING SHORTWAVE TRANSLATE W-E...
CATEGORICAL POPS STILL APPEAR ON TRACK...SPREADING INTO WRN UPPER MI
THIS EVENING AND INTO THE CNTRL OVERNIGHT. SNOW MAY NOT REACH THE
FAR E AROUND KERY UNTIL TOWARD 12Z. AVERAGED MODEL QPF INDICATES 0.1
TO 0.2 INCHES OF QPF TONIGHT...SUGGESTING 1-2 INCHES OF SNOW IN
GENERAL AS SNOW TO WATER RATIOS SHOULDN`T BE MUCH MORE THAN 10-12 TO
1. THESE NUMBERS APPEAR ON TRACK FROM AN ISENTROPIC STANDPOINT AS
MIXING RATIOS OF AROUND 3G/KG ARE AVBL WITH CLOSE TO 6HRS OF ASCENT.
SNOW ACCUMULATIONS WILL BE LIGHTEST OVER THE E SINCE SNOW DOESN`T
BEGIN UNTIL NEAR THE END OF THE TONIGHT PERIOD. CLOUDS/PCPN/WINDS
WILL KEEP TEMPS FROM FALLING MORE THAN ROUGHLY 2-4 DEGREES FROM
TODAYS HIGH TEMPS.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 323 PM EST SUN DEC 7 2014
GOOD AGREEMENT IN LARGER SCALE PATTERN THROUGH THE LENGTH OF THE
LONG TERM INTO NEXT WEEKEND. LOW PRESSURE THAT CROSSES THE AREA ON
MONDAY WILL BE WEAKENING AS IS SLIDES EAST OF LK SUPERIOR BY TUESDAY
MORNING. NNW FLOW LAKE ENHANCEMENT...AT LEAST IN DIMINISHING
STATE...EXPECTED MONDAY EVENING OVER WESTERN UPR MICHIGAN...ESPECIALLY
OVER THE KEWEENAW WHERE DEEPER MOISTURE TO H7 LINGERS AND H85 TEMPS
DROP TO AROUND -8C. LOW-LEVEL WINDS NOT TOO CYCLONIC SO CONVERGENCE
WILL BE WEAK. SNOW ACCUMS MONDAY EVENING SHOULD BE NOTHING MORE THAN
A COUPLE INCHES FOR NW CWA. DEPARTING DEEP MOISTURE AND LIMITED COLD
AIR /H9-H85 TEMPS -8C TO -10C/ IS MARGINAL FOR PURE LAKE EFFECT...SO
SNOW SHOWERS SHOULD DIMINISH SHARPLY AFTER MIDNIGHT ALL CWA. LIGHT
LES COULD CONTINUE INTO TUESDAY MORNING...BUT CONTINUED DRYING AND
SFC RIDGING WILL SPELL AN END TO LES TUE AFTN.
BEYOND MONDAY NIGHT...APPEARS QUIET WITH NO BIG STORMS OVER THE
UPPER GREAT LAKES. UPPER LEVEL FLOW FEATURES RIDGING BUILDING OVER
THE MID PORTION OF THE CONUS MID TO LATE WEEK. MEANWHILE...DEEPENING
TROUGH OVER THE EASTERN CONUS WILL RESULT IN STRONG EAST COAST STORM
THAT WILL BRING HEAVY SNOW TO INTERIOR PORTIONS OF THE NORTHEAST AND
NEW ENGLAND. THE BUILDING UPR RIDGE WILL LEAD TO SPRAWLING SFC RIDGE
FM CENTRAL PLAINS AND NORTHERN ONTARIO ON TUESDAY ONLY MOVING SLOWLY
TO NORTHERN QUEBEC TO LOWER MISSISSIPPI RIVER VALLEY BY FRIDAY.
COULD BE A COUPLE CHILLY NIGHTS INLAND ON TUESDAY NIGHT AND
WEDNESDAY NIGHT WITH THE RIDGE OVERHEAD AND AS PWATS ARE BLO 75 PCT
OF NORMAL. DEPENDING ON CLOUD COVER...MINS EITHER NIGHT MAY FALL
TOWARD ZERO. FOR NOW HAVE SOME SINGLE DIGITS ABOVE ZERO IN THERE
UNTIL CAN GET BETTER HANDLE ON EXTENT OF MID CLOUDS.
BY NEXT WEEKEND UPPER LEVEL RIDGE AXIS IS OVER THE WESTERN GREAT
LAKES. SW FLOW SFC-H85 WILL TRANSPORT HIGHER DWPNTS FM THE CNTRL
PLAINS INTO THE GREAT LAKES. YET IT IS NOT UNTIL SATURDAY NIGHT INTO
SUNDAY THAT SFC DWPNTS ARE FORECAST TO BE OVER 32F. SOUNDINGS FM GFS
INDICATE SHALLOWER MOISTURE THAN THEY SHOWED YDY FOR FRIDAY AND
SATURDAY...SO COULD HAVE AT LEAST SOME SUNSHINE WHICH WOULD ALLOW
TEMPS TO WARM INTO THE MID 30S TO LOWER 40S. SHOT UP SLIGHTLY HIGHER
THAN BLENDED GUIDANCE. ONCE DWPNTS RISE ABOVE FREEZING SATURDAY
NIGHT INTO SUNDAY...THERE WILL BE INCREASING PROSPECTS OF DRIZZLE
AND FOG AS THIS MOISTURE RIDES OVER GRADUAL MELTING SNOWPACK. ECMWF
AND GFS ALSO INDICATE MOISTURE DEPTH INCREASES WITH SOME WEAK LIFT
DEVELOPING DUE TO SHORTWAVE ENERGY WORKING OVER THE AREA OUT AHEAD
OF TROUGH AXIS OVER WESTERN CONUS. WILL HAVE SMALL POPS IN THERE FOR
RAIN LATE IN THE WEEKEND. ALSO WILL INCLUDE MENTION OF FOG SINCE
DWPNTS ARE FORECAST IN THE MID-UPR 30S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 125 PM EST SUN DEC 7 2014
TIGHTENING PRES GRADIENT BTWN EXITING HIGH PRES TO THE E AND LOW
PRES APPROACHES FROM THE W WILL LEAD TO SOUTHERLY WINDS GUSTING OVER
20 KT THIS AFTERNOON INTO THIS EVENING. OTHERWISE...WITH LOW-LEVELS
REMAINING DRY...VFR CONDITIONS WILL PREVAIL AT KIWD/KCMX/KSAW INTO
EARLY EVENING. TONIGHT...-SN DEVELOPING AHEAD OF THE APPROACHING LOW
PRES SYSTEM WILL SPREAD E INTO UPPER MI. ALL TERMINALS WILL FALL TO
MVFR. WITH SOMEWHAT HEAVIER SNOW EXPECTED AT KCMX/KSAW...THERE MAY BE
SOME PERIODS OF IFR VIS. LOOK FOR ALL SITES TO LOWER TO IFR CIGS BY
MON MORNING AS LOW-LVL MOISTURE GETS TRAPPED UNDER LOWERING
SUBSIDENCE INVERSION.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 338 PM EST SUN DEC 7 2014
TIGHTENING PRES GRADIENT AND PRES FALLS SHIFTING INTO THE UPPER
LAKES AHEAD OF AN APPROACHING LOW PRES WILL RESULT IN SOUTHERLY
GALES TONIGHT INTO MONDAY MORNING OVER THE EAST HALF OF LAKE
SUPERIOR. WINDS OVER THE W WL STAY MOSTLY BLO 30KT. AS LOW PRES/COLD
FRONT MOVE ACROSS THE UPPER LAKES LATE MON/MON EVENING...WINDS WILL
SHIFT TO THE NW-N. WITH SYSTEM TRENDING WEAKER AS IT
DEPARTS...EXPECT WINDS TO STAY BLO GALES MON NIGHT INTO TUE...NO
HIGHER THAN 30KT MAINLY CENTRAL AND EAST. HIGH PRES RIDGE ARRIVING
TUE NIGHT/WED MAY LINGER INTO THE END OF THE WEEK AND RESULT IN
WINDS UNDER 20KT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING FROM 7 PM THIS EVENING TO 10 AM EST MONDAY FOR
LSZ267.
GALE WARNING UNTIL 10 AM EST MONDAY FOR LSZ266.
GALE WARNING UNTIL 3 AM EST MONDAY FOR LSZ248-249-265.
GALE WARNING FROM 7 PM THIS EVENING TO 3 AM EST MONDAY FOR
LSZ250.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...VOSS
LONG TERM...JLA
AVIATION...VOSS
MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
327 PM EST SUN DEC 7 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 538 AM EST SUN DEC 7 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A WELL-DEFINED SHORTWAVE
MOVING ACROSS MT EARLY THIS MORNING. THIS WAVE WILL BE THE FEATURE
OF INTEREST IN THE SHORT TERM AS IT SHIFTS E...REACHING THE UPPER
GREAT LAKES MON. AT THE SFC...SHORTWAVE WAS SUPPORTING LOW PRES OVER
SRN SASKATCHEWAN. TO THE E...HIGH PRES CENTER HAS SLIPPED E OF LAKE
SUPERIOR/UPPER MI. STRONG WAA/ISENTROPIC ASCENT REGIME BTWN THE
SHORTWAVE AND DEPARTING HIGH PRES HAS LED TO QUITE A BIT OF MID
LEVEL CLOUDINESS SPREADING INTO UPPER MI DURING THE NIGHT. RADARS
ARE ALSO SHOWING RETURNS...BUT SO FAR...THE FARTHEST S ANY -SN HAS
BEEN REPORTED IN OBS IS AT THUNDER BAY ONTARIO AS DRY AIR NOTED
BELOW 750MB ON 00Z KINL SOUNDING IS WORKING TO LIMIT SOUTHWARD
EXTENT OF -SN REACHING THE GROUND.
TODAY...SHORTWAVE OVER MT WILL MOVE TO THE ERN DAKOTAS WITH
ASSOCIATED SFC LOW REACHING FAR SE MANITOBA BY EVENING. STRONG
WAA/ISENTROPIC ASCENT WHICH IS CURRENTLY FOCUSED INTO NRN MN WILL
SHIFT E TODAY...BUT MODELS CONTINUE TO INDICATE THAT LOW-LEVELS WILL
FAIL TO MOISTEN ACROSS UPPER MI DUE TO A PERSISTENT FEED OF
LOW-LEVEL DRY AIR FROM DEPARTING HIGH PRES. TO THE W...AXIS OF
850-700MB MOISTURE TRANSPORT AND LOWERING CONDENSATION PRES DEFICITS
AHEAD OF SHORTWAVE REMAINS JUST W OF THE AREA THRU THE AFTN. SO...
NOT EXPECTING ANY PCPN DURING THE DAYLIGHT HRS TODAY. TEMPS SHOULD
REACH THE UPPER 20S/LWR 30S.
TONIGHT...AS RIBBON OF 850-700MB MOISTURE TRANSPORT...ISENTROPIC
ASCENT ENHANCED BY 850MB WINDS OF 40-50KT AND DEEP LAYER QVECTOR
CONVERGENCE IN ADVANCE OF APPROACHING SHORTWAVE TRANSLATE W-E...
CATEGORICAL POPS STILL APPEAR ON TRACK...SPREADING INTO WRN UPPER MI
THIS EVENING AND INTO THE CNTRL OVERNIGHT. SNOW MAY NOT REACH THE
FAR E AROUND KERY UNTIL TOWARD 12Z. AVERAGED MODEL QPF INDICATES 0.1
TO 0.2 INCHES OF QPF TONIGHT...SUGGESTING 1-2 INCHES OF SNOW IN
GENERAL AS SNOW TO WATER RATIOS SHOULDN`T BE MUCH MORE THAN 10-12 TO
1. THESE NUMBERS APPEAR ON TRACK FROM AN ISENTROPIC STANDPOINT AS
MIXING RATIOS OF AROUND 3G/KG ARE AVBL WITH CLOSE TO 6HRS OF ASCENT.
SNOW ACCUMULATIONS WILL BE LIGHTEST OVER THE E SINCE SNOW DOESN`T
BEGIN UNTIL NEAR THE END OF THE TONIGHT PERIOD. CLOUDS/PCPN/WINDS
WILL KEEP TEMPS FROM FALLING MORE THAN ROUGHLY 2-4 DEGREES FROM
TODAYS HIGH TEMPS.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 323 PM EST SUN DEC 7 2014
GOOD AGREEMENT IN LARGER SCALE PATTERN THROUGH THE LENGTH OF THE
LONG TERM INTO NEXT WEEKEND. LOW PRESSURE THAT CROSSES THE AREA ON
MONDAY WILL BE WEAKENING AS IS SLIDES EAST OF LK SUPERIOR BY TUESDAY
MORNING. NNW FLOW LAKE ENHANCEMENT...AT LEAST IN DIMINISHING
STATE...EXPECTED MONDAY EVENING OVER WESTERN UPR MICHIGAN...ESPECIALLY
OVER THE KEWEENAW WHERE DEEPER MOISTURE TO H7 LINGERS AND H85 TEMPS
DROP TO AROUND -8C. LOW-LEVEL WINDS NOT TOO CYCLONIC SO CONVERGENCE
WILL BE WEAK. SNOW ACCUMS MONDAY EVENING SHOULD BE NOTHING MORE THAN
A COUPLE INCHES FOR NW CWA. DEPARTING DEEP MOISTURE AND LIMITED COLD
AIR /H9-H85 TEMPS -8C TO -10C/ IS MARGINAL FOR PURE LAKE EFFECT...SO
SNOW SHOWERS SHOULD DIMINISH SHARPLY AFTER MIDNIGHT ALL CWA. LIGHT
LES COULD CONTINUE INTO TUESDAY MORNING...BUT CONTINUED DRYING AND
SFC RIDGING WILL SPELL AN END TO LES TUE AFTN.
BEYOND MONDAY NIGHT...APPEARS QUIET WITH NO BIG STORMS OVER THE
UPPER GREAT LAKES. UPPER LEVEL FLOW FEATURES RIDGING BUILDING OVER
THE MID PORTION OF THE CONUS MID TO LATE WEEK. MEANWHILE...DEEPENING
TROUGH OVER THE EASTERN CONUS WILL RESULT IN STRONG EAST COAST STORM
THAT WILL BRING HEAVY SNOW TO INTERIOR PORTIONS OF THE NORTHEAST AND
NEW ENGLAND. THE BUILDING UPR RIDGE WILL LEAD TO SPRAWLING SFC RIDGE
FM CENTRAL PLAINS AND NORTHERN ONTARIO ON TUESDAY ONLY MOVING SLOWLY
TO NORTHERN QUEBEC TO LOWER MISSISSIPPI RIVER VALLEY BY FRIDAY.
COULD BE A COUPLE CHILLY NIGHTS INLAND ON TUESDAY NIGHT AND
WEDNESDAY NIGHT WITH THE RIDGE OVERHEAD AND AS PWATS ARE BLO 75 PCT
OF NORMAL. DEPENDING ON CLOUD COVER...MINS EITHER NIGHT MAY FALL
TOWARD ZERO. FOR NOW HAVE SOME SINGLE DIGITS ABOVE ZERO IN THERE
UNTIL CAN GET BETTER HANDLE ON EXTENT OF MID CLOUDS.
BY NEXT WEEKEND UPPER LEVEL RIDGE AXIS IS OVER THE WESTERN GREAT
LAKES. SW FLOW SFC-H85 WILL TRANSPORT HIGHER DWPNTS FM THE CNTRL
PLAINS INTO THE GREAT LAKES. YET IT IS NOT UNTIL SATURDAY NIGHT INTO
SUNDAY THAT SFC DWPNTS ARE FORECAST TO BE OVER 32F. SOUNDINGS FM GFS
INDICATE SHALLOWER MOISTURE THAN THEY SHOWED YDY FOR FRIDAY AND
SATURDAY...SO COULD HAVE AT LEAST SOME SUNSHINE WHICH WOULD ALLOW
TEMPS TO WARM INTO THE MID 30S TO LOWER 40S. SHOT UP SLIGHTLY HIGHER
THAN BLENDED GUIDANCE. ONCE DWPNTS RISE ABOVE FREEZING SATURDAY
NIGHT INTO SUNDAY...THERE WILL BE INCREASING PROSPECTS OF DRIZZLE
AND FOG AS THIS MOISTURE RIDES OVER GRADUAL MELTING SNOWPACK. ECMWF
AND GFS ALSO INDICATE MOISTURE DEPTH INCREASES WITH SOME WEAK LIFT
DEVELOPING DUE TO SHORTWAVE ENERGY WORKING OVER THE AREA OUT AHEAD
OF TROUGH AXIS OVER WESTERN CONUS. WILL HAVE SMALL POPS IN THERE FOR
RAIN LATE IN THE WEEKEND. ALSO WILL INCLUDE MENTION OF FOG SINCE
DWPNTS ARE FORECAST IN THE MID-UPR 30S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 125 PM EST SUN DEC 7 2014
TIGHTENING PRES GRADIENT BTWN EXITING HIGH PRES TO THE E AND LOW
PRES APPROACHES FROM THE W WILL LEAD TO SOUTHERLY WINDS GUSTING OVER
20 KT THIS AFTERNOON INTO THIS EVENING. OTHERWISE...WITH LOW-LEVELS
REMAINING DRY...VFR CONDITIONS WILL PREVAIL AT KIWD/KCMX/KSAW INTO
EARLY EVENING. TONIGHT...-SN DEVELOPING AHEAD OF THE APPROACHING LOW
PRES SYSTEM WILL SPREAD E INTO UPPER MI. ALL TERMINALS WILL FALL TO
MVFR. WITH SOMEWHAT HEAVIER SNOW EXPECTED AT KCMX/KSAW...THERE MAY BE
SOME PERIODS OF IFR VIS. LOOK FOR ALL SITES TO LOWER TO IFR CIGS BY
MON MORNING AS LOW-LVL MOISTURE GETS TRAPPED UNDER LOWERING
SUBSIDENCE INVERSION.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 538 AM EST SUN DEC 7 2014
TIGHTENING PRES GRADIENT AND PRES FALLS SHIFTING INTO THE UPPER
LAKES AHEAD OF APPROACHING LOW PRES WILL RESULT IN INCREASING
SOUTHERLY WINDS TODAY/TONIGHT. ACROSS THE E HALF OF LAKE SUPERIOR...
WIND GUSTS WILL LIKELY REACH GALE FORCE LATER THIS AFTN THRU TONIGHT
WHILE WINDS OVER THE W STAY MOSTLY BLO 30KT. AS LOW PRES/COLD FRONT
MOVE ACROSS THE UPPER LAKES LATE MON/MON EVENING...WINDS WILL SHIFT
TO THE NW-N. WITH SYSTEM TRENDING WEAKER AS IT DEPARTS...THESE WINDS
WILL LIKELY NOT BE AS STRONG AS PREVIOUSLY THOUGHT. SO...IT NOW
APPEARS GALES PROBABLY WON`T OCCUR ON THE BACKSIDE OF THE SYSTEM MON
NIGHT INTO EARLY TUE. HIGH PRES RIDGE ARRIVING TUE NIGHT/WED WILL
BRING A PERIOD OF LIGHTER WINDS UNDER 20KT THAT MAY LINGER ON THRU
THU AS WELL.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING FROM 7 PM THIS EVENING TO 10 AM EST MONDAY FOR
LSZ267.
GALE WARNING UNTIL 10 AM EST MONDAY FOR LSZ266.
GALE WARNING UNTIL 3 AM EST MONDAY FOR LSZ248-249-265.
GALE WARNING FROM 7 PM THIS EVENING TO 3 AM EST MONDAY FOR
LSZ250.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...JLA
AVIATION...VOSS
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
135 PM EST SUN DEC 7 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 538 AM EST SUN DEC 7 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A WELL-DEFINED SHORTWAVE
MOVING ACROSS MT EARLY THIS MORNING. THIS WAVE WILL BE THE FEATURE
OF INTEREST IN THE SHORT TERM AS IT SHIFTS E...REACHING THE UPPER
GREAT LAKES MON. AT THE SFC...SHORTWAVE WAS SUPPORTING LOW PRES OVER
SRN SASKATCHEWAN. TO THE E...HIGH PRES CENTER HAS SLIPPED E OF LAKE
SUPERIOR/UPPER MI. STRONG WAA/ISENTROPIC ASCENT REGIME BTWN THE
SHORTWAVE AND DEPARTING HIGH PRES HAS LED TO QUITE A BIT OF MID
LEVEL CLOUDINESS SPREADING INTO UPPER MI DURING THE NIGHT. RADARS
ARE ALSO SHOWING RETURNS...BUT SO FAR...THE FARTHEST S ANY -SN HAS
BEEN REPORTED IN OBS IS AT THUNDER BAY ONTARIO AS DRY AIR NOTED
BELOW 750MB ON 00Z KINL SOUNDING IS WORKING TO LIMIT SOUTHWARD
EXTENT OF -SN REACHING THE GROUND.
TODAY...SHORTWAVE OVER MT WILL MOVE TO THE ERN DAKOTAS WITH
ASSOCIATED SFC LOW REACHING FAR SE MANITOBA BY EVENING. STRONG
WAA/ISENTROPIC ASCENT WHICH IS CURRENTLY FOCUSED INTO NRN MN WILL
SHIFT E TODAY...BUT MODELS CONTINUE TO INDICATE THAT LOW-LEVELS WILL
FAIL TO MOISTEN ACROSS UPPER MI DUE TO A PERSISTENT FEED OF
LOW-LEVEL DRY AIR FROM DEPARTING HIGH PRES. TO THE W...AXIS OF
850-700MB MOISTURE TRANSPORT AND LOWERING CONDENSATION PRES DEFICITS
AHEAD OF SHORTWAVE REMAINS JUST W OF THE AREA THRU THE AFTN. SO...
NOT EXPECTING ANY PCPN DURING THE DAYLIGHT HRS TODAY. TEMPS SHOULD
REACH THE UPPER 20S/LWR 30S.
TONIGHT...AS RIBBON OF 850-700MB MOISTURE TRANSPORT...ISENTROPIC
ASCENT ENHANCED BY 850MB WINDS OF 40-50KT AND DEEP LAYER QVECTOR
CONVERGENCE IN ADVANCE OF APPROACHING SHORTWAVE TRANSLATE W-E...
CATEGORICAL POPS STILL APPEAR ON TRACK...SPREADING INTO WRN UPPER MI
THIS EVENING AND INTO THE CNTRL OVERNIGHT. SNOW MAY NOT REACH THE
FAR E AROUND KERY UNTIL TOWARD 12Z. AVERAGED MODEL QPF INDICATES 0.1
TO 0.2 INCHES OF QPF TONIGHT...SUGGESTING 1-2 INCHES OF SNOW IN
GENERAL AS SNOW TO WATER RATIOS SHOULDN`T BE MUCH MORE THAN 10-12 TO
1. THESE NUMBERS APPEAR ON TRACK FROM AN ISENTROPIC STANDPOINT AS
MIXING RATIOS OF AROUND 3G/KG ARE AVBL WITH CLOSE TO 6HRS OF ASCENT.
SNOW ACCUMULATIONS WILL BE LIGHTEST OVER THE E SINCE SNOW DOESN`T
BEGIN UNTIL NEAR THE END OF THE TONIGHT PERIOD. CLOUDS/PCPN/WINDS
WILL KEEP TEMPS FROM FALLING MORE THAN ROUGHLY 2-4 DEGREES FROM
TODAYS HIGH TEMPS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 407 AM EST SUN DEC 7 2014
MODELS ARE IN GOOD AGREEMENT MON THROUGH THU...WITH LESS AGREEMENT
FRI AND SAT. A SHORTWAVE WILL MOVE FROM WRN LAKE SUPERIOR TO NRN
LAKE SUPERIOR THEN TO ERN LAKE SUPERIOR STEADILY BETWEEN 12Z MON AND
06Z TUE. THIS WILL BRING A WEAKENING/BROADENING 1012-1016MB SFC LOW
ACROSS THE AREA AS THE SHORTWAVE MOVES ACROSS. THERMAL PROFILES WILL
SUPPORT ALL SNOW WITH THE EVENT FROM 12Z MON ON...BUT 850MB TEMPS
ONLY FALL TO A MINIMUM OF -8C AT 12Z TUE...WHICH IS WARMER THAN
PREVIOUS RUNS. THE DRY SLOT LOOKS TO BE MOVING INTO WRN UPPER MI
AROUND 12Z MON AS THE BEST FORCING IS OVER THE ERN CWA AND NRN LAKE
SUPERIOR. HAVE FOCUSED HIGHEST POPS IN THESE AREAS IN THE
MORNING...SHIFTING NE THROUGH THE DAY. WITH THE WRAP AROUND MOISTURE
AND COOL UPSLOPE FLOW...LAKE ENHANCED/UPSLOPE PRECIP WILL BECOME THE
FOCUS MON EVENING/MON NIGHT BEFORE DIMINISHING TUE AS A 1034MB SFC
RIDGE MOVES OVER LAKE SUPERIOR. DID REDUCE LAKE ENHANCED/UPSLOPE
POPS AS MODELS TREND WARMER WITH LOW LEVEL TEMPS. FOR MON THROUGH
TUE...GENERALLY HAVE SNOWFALL AMOUNTS OF 2-3 INCHES CLOSER TO LAKE
SUPERIOR...WITH 1 INCH OR SO INLAND.
UPPER RIDGING BUILDS INTO THE AREA THROUGH THE REST OF THE EXTENDED
WITH NO SIGNIFICANT SIGNAL FOR PRECIP. TEMPS WILL BE ON THE
INCREASE...WITH 850MB TEMPS INCREASING TO ABOVE 0C BY THU MORNING
AND MAKING IT UP TO AROUND 10C FRI NIGHT INTO SAT. OF
COURSE...TEMPERATURE INVERSION NEAR THE SFC WILL BE PRETTY STRONG SO
SFC TEMPS WILL BE MORE LIMITED...BUT COULD SEE HIGHS IN THE LOW 40S
IN SOME LOCATIONS ON SAT. MODELS DO SHOW A FEW HUNDREDTHS OF AN INCH
OF QPF FRI INTO SAT...BUT THINK THAT IS DUE TO MODELS OVERDOING LOW
LEVEL MOISTURE AS THEY NORMALLY DO WHEN THEY SIMULATE SNOWPACK
MELTING. DID NOT INCLUDE PRECIP IN THE FORECAST.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 125 PM EST SUN DEC 7 2014
TIGHTENING PRES GRADIENT BTWN EXITING HIGH PRES TO THE E AND LOW
PRES APPROACHES FROM THE W WILL LEAD TO SOUTHERLY WINDS GUSTING OVER
20 KT THIS AFTERNOON INTO THIS EVENING. OTHERWISE...WITH LOW-LEVELS
REMAINING DRY...VFR CONDITIONS WILL PREVAIL AT KIWD/KCMX/KSAW INTO
EARLY EVENING. TONIGHT...-SN DEVELOPING AHEAD OF THE APPROACHING LOW
PRES SYSTEM WILL SPREAD E INTO UPPER MI. ALL TERMINALS WILL FALL TO
MVFR. WITH SOMEWHAT HEAVIER SNOW EXPECTED AT KCMX/KSAW...THERE MAY BE
SOME PERIODS OF IFR VIS. LOOK FOR ALL SITES TO LOWER TO IFR CIGS BY
MON MORNING AS LOW-LVL MOISTURE GETS TRAPPED UNDER LOWERING
SUBSIDENCE INVERSION. &&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 538 AM EST SUN DEC 7 2014
TIGHTENING PRES GRADIENT AND PRES FALLS SHIFTING INTO THE UPPER
LAKES AHEAD OF APPROACHING LOW PRES WILL RESULT IN INCREASING
SOUTHERLY WINDS TODAY/TONIGHT. ACROSS THE E HALF OF LAKE SUPERIOR...
WIND GUSTS WILL LIKELY REACH GALE FORCE LATER THIS AFTN THRU TONIGHT
WHILE WINDS OVER THE W STAY MOSTLY BLO 30KT. AS LOW PRES/COLD FRONT
MOVE ACROSS THE UPPER LAKES LATE MON/MON EVENING...WINDS WILL SHIFT
TO THE NW-N. WITH SYSTEM TRENDING WEAKER AS IT DEPARTS...THESE WINDS
WILL LIKELY NOT BE AS STRONG AS PREVIOUSLY THOUGHT. SO...IT NOW
APPEARS GALES PROBABLY WON`T OCCUR ON THE BACKSIDE OF THE SYSTEM MON
NIGHT INTO EARLY TUE. HIGH PRES RIDGE ARRIVING TUE NIGHT/WED WILL
BRING A PERIOD OF LIGHTER WINDS UNDER 20KT THAT MAY LINGER ON THRU
THU AS WELL.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING FROM 7 PM THIS EVENING TO 10 AM EST MONDAY FOR
LSZ267.
GALE WARNING UNTIL 10 AM EST MONDAY FOR LSZ266.
GALE WARNING FROM 6 PM THIS EVENING TO 3 AM EST MONDAY FOR
LSZ248-249-265.
GALE WARNING FROM 7 PM THIS EVENING TO 3 AM EST MONDAY FOR
LSZ250.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...TITUS
AVIATION...VOSS
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1128 AM CST SUN DEC 7 2014
.UPDATE...
ISSUED AT 1109 AM CST SUN DEC 7 2014
SENT ANOTHER UPDATE TO THE FORECAST THIS MORNING AS WITH CLOUDS
AND AREAS OF FOG LINGERING A BIT LONGER THAN PREVIOUSLY
EXPECTED...DO NOT THINK THAT THE FORECAST AMOUNT OF SUNSHINE WILL
BE SUFFICIENT TO HELP TEMPERATURES CLIMB QUITE AS HIGH AS
PREVIOUSLY FORECAST. AS A RESULT...ADJUSTED FORECAST MAX TEMPS
DOWN A FEW DEGREES USING RAP GUIDANCE AS A REFERENCE...WITH NO
ADDITIONAL CHANGES NECESSARY TO PREVIOUS FORECAST AT THIS TIME.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 308 AM CST SUN DEC 7 2014
FOCUS IS ON FOG...STRATUS...AND DRIZZLE INTO THE MORNING HOURS.
AS EXPECTED STRATUS CONTINUES TO ADVECT TO THE NORTH AND WEST DURING
THE PRE DAWN HOURS AS WE HAVE TRANSITIONED TO SOUTHERLY LLVL FLOW.
TEMPS HAVE RISEN AS THE LOW CLOUD COVER HAS THICKENED AND FOR THE
MOST PART TEMPS ARE RIGHT AROUND THE FREEZING MARK OR JUST A DEGREE
OR TWO BELOW. TEMPERATURE AND DEWPOINT SPREADS HAVE CLOSED OR ARE
WITHIN A DEGREE OF EACH OTHER AND WE HAVE SEEN VSBYS DROP ACROSS A
GOOD PORTION OF OUR CWA ALREADY IN FOG AND BASED ON MODEL TRENDS THE
STRATUS/FOG/VSBY RESTRICTIONS OF SOME DEGREE SHOULD ENCOMPASS OUR
ENTIRE CWA BY DAYBREAK. VSBYS FOR THE MOST PART HAVE BEEN VARIABLE
DUE TO STEADY SOUTHERLY WINDS AROUND 10 MPH. CURRENTLY HAVE A
DENSE FOG ADVISORY IN EFFECT FOR OUR SE AREAS WHERE VSBYS WERE THE
LOWEST INITIALLY...BUT DENSE FOG HAS YET TO MATERIALIZE ON A
WIDESPREAD BASIS. DESPITE THIS...WITH TEMPS EITHER SIDE OF
FREEZING...HAVE A HARD TIME GETTING RID OF THE HEADLINE AS FOG IS
OUT THERE AND CANNOT RULE OUT MINIMAL ICING ON ELEVATED SFCS FOR A
FEW MORE HOURS.
ALOFT...A SHORTWAVE TROUGH WAS TRANSLATING FM THE HIGH PLAINS ACROSS
THE CENTRAL PLAINS AND LIFT OVER THE LLVL MOISTURE COMBINED AND THE
BOUNDARY LAYER MIXING MAY GENERATE DRIZZLE AND/OR FREEZING DRIZZLE
BASED ON SFC TEMPS EITHER SIDE OF FREEZING. WE HAVE SEEN SOME LIGHT
RADAR RETURNS BUT NO REPORTS OF PCPN ON OBS AND MODELS HAVE TRENDED
DOWN FOR RECEIVING MEASURABLE PCPN AS THE SYSTEM MOVES THROUGH.
BASED ON CURRENT CONDITIONS AND LATEST MODELS...EXPECT DRIZZLE IF
ANYTHING VS RAIN...WITH LITTLE IF ANY ACCUMULATION. THE MID LEVEL
TROUGH AXIS PASSES EAST OF OUR WESTERN ZONES BY MID MORNING AND
AROUND MID DAY FOR OUR EASTERN ZONES AND ANY LIGHT DRIZZLE WILL
COME TO AN END AND VSBYS WILL IMPROVE AS THIS SYSTEM EXITS THE
AREA. A NORTHERN PLAINS TROUGH AND ASSOCIATED COLD FRONT WILL
FINALLY SCOUR THE LOW CLOUDS/LLVL MOISTURE TO THE EAST BY THE
EVENING.
TEMPS LOOK TO STRUGGLE DUE TO THE LINGERING LOW CLOUDS FOR A GOOD
PORTION OF THE DAY AND HAVE BACKED OFF ON HIGHS A FEW DEGREES. NOT
A WHOLE LOT TO SAY ABOUT TONIGHT WITH DRY CONDITIONS FORECAST FOR
OUR REGION WHILE AN UPPER WAVE MOVES INTO THE UPPER MIDWEST/GREAT
LAKES AREA.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 308 AM CST SUN DEC 7 2014
A SURFACE HIGH PRESSURE SYSTEM WILL BUILD INTO THE REGION MONDAY AND
MONDAY NIGHT. THIS WILL BRING PARTLY CLOUDY SKIES...LIGHT WINDS AND
MILD DAY TIME TEMPERATURES WITH A COOL NIGHT. AS THE HIGH MOVES TO
THE EAST TUESDAY...WINDS WILL TURN TO THE SOUTH AND MOISTURE
INCREASES ACROSS THE AREA. AT THE SAME TIME A WEAK UPPER LEVEL WAVE
WILL MOVE INTO THE AREA. TUESDAY WILL BE A LITTLE COOLER BUT STILL
ABOVE NORMAL. TUESDAY NIGHT THE UPPER WAVE MOVES THROUGH AND THE
MOISTURE SPREADS ACROSS THE FORECAST AREA. CLOUDS WILL INCREASE
DURING THE NIGHT. THE CLOUDS ARE EXPECTED TO LINGER INTO WEDNESDAY
BEFORE GRADUALLY MOVING OUT. THE CLOUDS WILL KEEP TEMPERATURES FROM
WARMING AS MUCH. WEDNESDAY NIGHT THE CLOUDS WILL CONTINUE TO
DIMINISH.
THURSDAY THROUGH FRIDAY AN UPPER LEVEL RIDGE BUILDS INTO THE AREA.
THIS WILL ALLOW FOR SOME WARM ADVECTION AND WARMER TEMPERATURES
AGAIN. BY SATURDAY ANOTHER UPPER LEVEL TROUGH WILL MOVE INTO THE
ROCKIES. A SURFACE LOW DEVELOPS ON THE HIGH PLAINS AND WINDS TURN TO
THE SOUTH AND INCREASE. MOISTURE ONCE AGAIN RETURNS TO THE AREA AND
CLOUDS INCREASE. TEMPERATURES REMAIN MILD.
&&
.AVIATION...(FOR THE 18Z KGRI/KEAR TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1109 AM CST SUN DEC 7 2014
IMPROVING CIGS AND VSBYS ARE EXPECTED AT BOTH TERMINALS OVER THE
NEXT FEW HOURS AS A PASSING DISTURBANCE HELPS TO SCOUR OUT THE LOW
LEVEL CLOUD DECK. WHILE CONDITIONS WILL IMPROVE EARLY THIS
AFTERNOON...DO NOT EXPECT A RETURN TO PREVAILING VFR CONDITIONS
UNTIL ABOUT 07/21Z...WITH LIGHT NORTH WESTERLY WINDS AND MOSTLY
CLEAR SKIES RETURNING THIS EVENING AND THEN PERSISTING THROUGH
MONDAY AFTERNOON AS A RIDGE OF HIGH PRESSURE TRANSITIONS ACROSS
THE CENTRAL PLAINS.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...ROSSI
SHORT TERM...FAY
LONG TERM...JCB
AVIATION...ROSSI
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
232 PM CST SUN DEC 7 2014
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 230 PM CST SUN DEC 7 2014
UPPER LOW PUSHING ACROSS NORTH DAKOTA AT THIS TIME...DRAGGING A COLD
FRONT ACROSS THE REGION. STRATUS IS ERODING FROM WEST TO EAST...WITH
TEMPERATURES JUMPING INTO THE 40S AND 50S ALONG AND WEST OF THE
JAMES RIVER. READINGS STUCK IN THE 30S ALONG AND EAST OF INTERSTATE
29 WHERE LOW STRATUS IS HOLDING. SEEING PATCHY DRIZZLE AHEAD OF THE
FRONT WHERE DEEPER SATURATION AND WEAK LIFT IS PRESENT. SOME AREAS
STILL HOLDING RIGHT AROUND FREEZING NEAR THE BUFFALO RIDGE AND
ADJACENT AREAS OF NORTHWEST IOWA. DRIZZLE IS PRETTY LIGHT AND NOT
HEARING OF ANY ISSUES...BUT SOME ICY SPOTS ARE STILL A POSSIBILITY
THROUGH THIS AFTERNOON IN THOSE AREAS. EXPECT STRATUS TO CLEAR
INTERSTATE 29 BY MID AFTERNOON...WITH CLEARING PUSHING INTO
NORTHWEST IOWA THIS EVENING. SOME STRATUS...FOG AND DRIZZLE MAY
LINGER IN OUR FAR EAST UNTIL AROUND MIDNIGHT.
FOCUS THEN IS ON THE UPPER LOW THAT MOVES ACROSS TONIGHT. CURRENTLY
SEEING SOME LOWER CLOUDS AND LIGHT PRECIPITATION WITH THIS FEATURE
ACROSS WESTERN MONTANA...AND MODELS ARE CONSISTENT IN BRINGING THIS
INTO OUR AREA TONIGHT. THUS WILL LIKELY SEE A RETURN OF
STRATUS...ESPECIALLY EAST OF THE JAMES RIVER. SATURATION DOES GET
PRETTY DEEP WITH SOME WEAK LIFT AS WELL...THUS SEEMS LIKE DRIZZLE
MAY AGAIN BE A POSSIBILITY. EXPECT TEMPERATURES TO MAINLY BE ABOVE
FREEZING...ALTHOUGH BY LATE TONIGHT MOST OF THE REGION SHOULD FALL
BACK BELOW FREEZING. THUS MAY BE A FEW ICY SPOTS AGAIN BY
MORNING...BUT AT THIS TIME NOT EXPECTING PRECIPITATION TO BE HEAVY
ENOUGH TO CAUSE MUCH OF AN ISSUE. WILL MONITOR TRENDS OVERNIGHT.
STRATUS AND STRATOCU WILL LIKELY HOLD THROUGH THE DAY MONDAY...WITH
CLOUDY SKIES OVER SOUTHWEST MINNESOTA...PARTLY TO MOSTLY CLOUDY FROM
HURON TO SIOUX FALLS TO SIOUX CITY AND MOSTLY SUNNY WEST OF THE
JAMES RIVER. HIGHS WILL RANGE FROM AROUND 30 IN SOUTHWEST MINNESOTA
TO THE LOW AND MID 40S ALONG THE MISSOURI RIVER. AS THE SECONDARY
COLD FRONT MOVES THROUGH IN THE EARLY AFTERNOON...EXPECT
TEMPERATURES NORTH OF INTERSTATE 90 TO REMAIN STEADY OR SLOWLY FALL
THROUGH THE AFTERNOON HOURS. WILL BE BREEZY OUT OF THE NORTHWEST AS
WELL WITH GUSTS OF 25 TO 35 MPH. AT THIS TIME THINK IT STAYS
DRY...ALTHOUGH CAN NOT RULE OUT A FEW FLURRIES WITH THE CLOUDS IN
SOUTHWEST MINNESOTA.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 230 PM CST SUN DEC 7 2014
ONLY MINOR ADJUSTMENTS MADE TO THE ONGOING FORECAST FROM MONDAY
NIGHT THROUGH NEXT WEEKEND. FORECAST REMAINS ON TRACK SHOWING A
SECONDARY COLD FRONT ARRIVING LATE MONDAY AFTERNOON OR MONDAY
EVENING. THE COLDEST DAY OF THE NEXT 7 DAYS WILL FALL ON TUESDAY AS
READINGS STRUGGLE TO REACH THE FREEZING MARK. TEMPERATURES COULD BE
A SHADE TOO WARM EVEN...ESPECIALLY OVER THE CENTRAL ZONES.
WE HAVE TO CONTINUE MONITORING MINOR SHORTWAVE MOVING THROUGH THE
PLAINS TUESDAY NIGHT INTO WEDNESDAY. NAM/GFS CONTINUE TO PULL OR
LINGER LOW LVL MOISTURE WITHIN THE MISSOURI RIVER VALLEY. NAM
SOUNDS SHOW A MUCH DEEPER MOISTURE LAYER THAN THE GFS...WHICH GIVEN
WEAK ISENTROPIC LIFT COULD RESULT IN LIGHT DRIZZLE/FOG INTO
WEDNESDAY MORNING SOUTH OF I-90. GIVEN THE AFOREMENTIONED MODELS
OVER FORECASTING OF MOISTURE...WILL HOLD OFF ON ANY PRECIP MENTION
ATTM.
FROM THURSDAY-SUNDAY...A VERY WARM PATTERN CONTINUES TO SHOW ITS
HAND...ESPECIALLY FOR FRIDAY AND SATURDAY. LOW LVL MOISTURE AND
STRATUS WILL CONTINUE TO PLAY A ROLE...HOWEVER THE PERSISTENT
SOUTHWESTERLY FLOW WILL CONTINUE TO ADVECT THE WARMER AIR OFF THE
SOUTHERN AND WESTERN PLAINS NORTHEAST INTO THE WEEKEND. AGAIN...HAVE
TRENDED TOWARDS WPC/ECMWF GUIDANCE...WHICH IS NO LONGER THAT MUCH
WARMER THAN NUMBERS FROM ECMWF/GFS ENSEMBLE GUIDANCE PROGS. WHILE
FEW ANALOGS EXISTS FOR THIS MID-DECEMBER SETUP...120 HR CIPS
ANALOG GUIDANCE DOES SUGGEST 30-40 PERCENT PROBS OF 60 DEGREE
READINGS OVER THE WESTERN CWA ON FRIDAY...WITH NEARLY 60-80
PERCENT PROBS OF 50+ OVER MUCH OF THE CWA. GIVEN THE PERSISTENT
SWLY LOW LVL AND BOUNDARY LAYER FLOW...CONCERNED THAT FRIDAY NIGHT
LOWS COULD BE MUCH TOO COLD AND SATURDAY COULD BE EVEN WARMER THAN
FRIDAY. STILL A FEW DAYS OUT TO WATCH MODEL GUIDANCE ADJUST.
BEYOND THE WEEKEND...LITTLE TO NO CONFIDENCE IN THE WEATHER DETAILS
BEYOND SUNDAY. LONG RANGE MODELS HANDLING THE EVENTUAL EASTWARD
PROGRESSION AND PHASING OF SOUTHWESTERN ENERGY WITH NORTHERN STREAM
MUCH DIFFERENTLY WITH EACH MODEL RUN.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 230 PM CST SUN DEC 7 2014
STRATUS...FOG AND DRIZZLE CONTINUES TO EXIT THE AREA FROM WEST TO
EAST THIS AFTERNOON. FOLLOWED CLOSE TO THE RAP FOR TIMING THE EXIT
AND RETURN TO VFR. COULD SEE IFR TO LIFR FOG AND STRATUS LINGER
ACROSS PORTIONS OF NORTHWEST IOWA UNTIL MIDNIGHT. AS THE UPPER LOW
SWINGS ACROSS TONIGHT...EXPECT A RETURN TO MVFR CIGS. COULD EVEN BE
LOWER FOR A PERIOD...SO WILL HAVE TO WATCH UPSTREAM TRENDS. ALSO CAN
NOT RULE OUT SOME DRIZZLE TONIGHT AS THE STRATUS RETURNS.
TEMPERATURES SHOULD MAINLY BE ABOVE FREEZING WHEN ANY DRIZZLE
OCCURS...ALTHOUGH A CHANCE WE COULD SEE SOME VERY LIGHT FREEZING
DRIZZLE LATER TONIGHT...MAINLY NORTHEAST OF THE TAF SITES. MVFR CIGS
MAY VERY WELL LINGER INTO MONDAY...ALTHOUGH ALL THREE TAF SITES WILL
LIKELY BE NEAR THE EDGE OF THE BROKEN TO OVERCAST STRATUS DECK.
NORTHWEST WINDS WILL BECOME BLUSTERY TONIGHT...AND REMAIN THAT WAY
INTO MONDAY...WITH GUSTS OF 20 TO 30 KTS AT TIMES.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
SHORT TERM...CHENARD
LONG TERM...DUX
AVIATION...CHENARD
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
336 PM CST SUN DEC 7 2014
.SHORT TERM...
(Tonight and Monday)
The primary focus in the short term will be ongoing rain chances
and the return of fog and low visibilities to the forecast area.
Light rain showers will migrate east across the forecast area this
afternoon. Rainfall totals will remain low, though any precip will
assist in keeping the area moist. Inherited PoP grids are adequate
for expected weather this afternoon though new model data is
pessimistic about tonight and early tomorrow morning. Thus removed
mention of PoPs for that time period.
NAM, GFS, and RAP model soundings are optimistic about bringing fog
back into West Central Texas tonight. At this time, fog is
expected to form sometime after midnight and lift shortly after 9
A.M. tomorrow. Areas of fog will likely be more widespread
tonight than they were early this morning, extending from south of
Interstate 10 and north of Throckmorton. Light winds tonight and
added moisture from today`s rain showers promote this solution.
Cloud cover this morning kept temperatures from climbing too quickly
this morning resulting in afternoon high near normal. Tonight,
however, added moisture and low cloud ceilings will insulate the
forecast area and keep temperatures 5-7 degrees above normal.
Clearing skies tomorrow afternoon will allow for unseasonably warm
temperatures with highs mainly in the mid 60s.
18
.LONG TERM...
(Monday night through Sunday)
Shortwave ridging aloft Monday night will shift east as we head
into Tuesday as a weak shortwave trough moves across the
Rockies. This feature will move southeast into Plains by Wednesday
morning, slowing as it absorbs southern stream wave over the
southern Plains. Moisture will be slow to increase ahead of this
system, with dewpoints likely remaining in the lower 40s
throughout the day Tuesday. We should see ample high clouds,
keeping temperatures in the mid 60s Tuesday afternoon, but low
clouds are not expected until Tuesday night. This increasing
moisture and cloud cover will limit diurnal ranges and keep min
temps generally in the mid/upper 40s for Wednesday morning.
There are considerable differences in the midweek 500 mb pattern
between the GFS, ECMWF, and GEM, yielding low confidence in any
particular solution at this time. The GFS is the fastest of the
12z runs with the onset of isentropic ascent across West Central
TX with the ECMWF following suit 6-12 hours later. Given what has
been as progressive flow as of late, siding with a bit faster
solution seems reasonable. This broad, isentropic ascent will
result in an abundance of cloud cover Wednesday and Thursday with
a persistent southerly fetch at low-levels, maintaining modest
moisture advection. Rainfall is expected to be rather light,
similar to what we`re seeing today across the area, with amounts
typically under 1/10". The cloud cover and light precipitation
will also keep temps around 60 degrees, with the potential to be a
few degrees cooler if light rain showers are a bit more widespread
than anticipated. Low rain chances will hang around through
Thursday night as weak perturbations move through the flow aloft.
By Friday, we should see improving conditions as the shortwave
trough moves east and shortwave ridging returns. This should allow
a modest warm-up with dry weather anticipated heading into the
weekend. We are watching a rather strong trough setting course for
the west coast late in the week. The medium range models are
moving this trough across the Rockies over the weekend, backing
winds aloft to the southwest. The associated lee cyclogenesis will
enhance low-level winds and should promote increasing surface
moisture. The timing of this feature`s effects for West Central TX
is certainly up in the air at this time, but there is pretty
decent model consensus that a closed mid-level cyclone develops
and moves east-southeast into West TX around Sunday. This pattern
bears watching as it could provide the area with a good
opportunity for measurable rainfall. As usual, there is plenty of
time for things to change, but we`ll be watching!
Johnson
&&
.PRELIMINARY POINT TEMPS/POPS...
Abilene 40 66 43 66 45 / 5 0 0 0 10
San Angelo 40 66 43 66 45 / 5 0 0 5 20
Junction 41 68 41 66 45 / 10 5 0 0 10
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
18/25
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
330 PM CST SUN DEC 7 2014
.TONIGHT AND MONDAY...CONFIDENCE - MEDIUM.
MAIN 500 MB SHORTWAVE TROUGH IS WELL DEFINED OVER NORTH DAKOTA...AND
IS EXPECTED TO SHIFT EASTWARD INTO NORTHERN MINNESOTA TONIGHT...THEN
TO THE NORTHEAST ON MONDAY. A VORTICITY MAXIMUM TO THE SOUTH OF THE
MAIN SHORTWAVE TROUGH WILL SLIDE EAST TOWARD THE AREA LATER
TONIGHT...THEN THROUGH THE AREA MONDAY MORNING. ANOTHER STRONGER
VORTICITY MAXIMUM WILL SHIFT SOUTHEAST THROUGH THE AREA DURING THE
AFTERNOON.
MODEST WARM AIR ADVECTION AREA...COMBINED WITH MODEST LOW TO MID
LEVEL FRONTOGENESIS RESPONSE BAND...IS EXPECTED TO COMBINE WITH THE
LEAD VORTICITY MAXIMUM TO PRODUCE A 4 TO 5 HOUR WINDOW OF MODERATE
TO STRONG UPWARD VERTICAL MOTION WEST TO EAST ACROSS THE AREA. THE
TIMING FOR THIS BAND WILL BE AROUND MIDNIGHT IN THE FAR WESTERN
COUNTIES...TO AROUND 09Z TO 10Z MONDAY FOR THE LAKESHORE COUNTIES.
AREA FORECAST SOUNDINGS ARE SHOWING SOME DIFFERENCES. THE GFS/ECMWF
ARE THE MOST CONSISTENT AND CONTINUE TO SUPPORT A PERIOD OF LIGHT
SNOW AND LIGHT SLEET MIX ACROSS THE AREA. THE NAM IS MILDER WITH ITS
WARM LAYER ABOVE THE SURFACE AND INDICATES SOME LIGHT FREEZING RAIN
MIXING IN AT TIMES. THE RAP SOUNDINGS ALSO LEAN IN THIS DIRECTION
SOMEWHAT. LEANED TOWARD THE MORE CONSISTENT GFS/ECMWF AND WENT WITH
PREVAILING LIGHT SNOW AND LIGHT SLEET LATER TONIGHT INTO EARLY
MONDAY. KEPT CHANCES FOR LIGHT FREEZING RAIN IN THE SOUTH...IN CASE
MILDER MODELS ARE CORRECT.
SHOULD SEE SNOW AND SLEET ACCUMULATIONS AROUND 1.0 INCH IN MOST
AREAS...A BIT MORE IN THE FAR NORTHERN COUNTIES AND LESS NEAR LAKE
MICHIGAN. HOURLY RATES OF 0.1 TO 0.3 INCHES PER HOUR ARE EXPECTED.
GIVEN TIMING DURING THE MORNING COMMUTE ON MONDAY...CONSIDERED A
WINTER WEATHER ADVISORY. AFTER COLLABORATION WITH NEIGHBORING
OFFICES...HELD OFF AND ISSUED A SPECIAL WEATHER STATEMENT. EVENING
SHIFT WILL NEED TO CONSIDER ONE...ESPECIALLY IF GFS LEANS TOWARD THE
NAM/RAP WITH LIGHT FREEZING RAIN POTENTIAL.
STRONGER 500 MB VORTICITY MAXIMUM DURING THE AFTERNOON WILL CONTINUE
TO BRING CHANCES FOR LIGHT RAIN AND LIGHT SNOW MONDAY. PERHAPS THE
PRECIPITATION WILL BECOME MORE LIGHT RAIN LATER IN THE DAY...AS
SURFACE TEMPERATURES WARM ABOVE FREEZING. LOWS TONIGHT SHOULD BE IN
THE UPPER 20S TO LOWER 30S...WITH MIDDLE TO UPPER 30S ON MONDAY.
.MONDAY NIGHT THROUGH WEDNESDAY...CONFIDENCE - MEDIUM.
LINGERING WEAK LIFT AND LOW LEVEL RH MAY RESULT IN SOME LINGERING
FLURRIES OR DRIZZLE MONDAY EVENING BEFORE LOWER LEVELS FURTHER DRY.
WL CONTINUE LOW POPS FOR MEASUREABLE -RA/-SN IN THE EVE FOR THE FAR
EAST...CLOSER TO DEPARTING MID-LEVEL SHORT WAVE TROUGH.
OTHERWISE...SHORT WAVE RIDGING MOVES ACROSS WI LATER TUE INTO WED.
LOW LEVEL WINDS TURN MORE NORTHEAST FOR A TIME TUE/TUE NGT WITH
DELTA-T WITH DELTA-T INCREASING TO AROUND 6-7C. LOW LEVELS SLOWLY
WARM AT THIS TIME...AND SHORT TERM GUIDANCE IN DISAGREEMENT ON
AMOUNT OF VEERING OF WINDS DURING THIS PERIOD. HENCE WL HOLD OFF ON
ANY -SN OR FLURRY MENTION AT THIS TIME. TEMPERATURES REMAINING
CLOSE TO SEASONAL NORMAL THIS PERIOD.
.WEDNESDAY NIGHT THROUGH SUNDAY...CONFIDENCE - MEDIUM.
A QUIET PERIOD EXPECTED THROUGH SATURDAY WITH SOME MODERATION IN
TEMPERATURES. 00Z ECMWF AND ECMWF MEAN TRENDING TOWARD SLOWER
NORTHWARD MOVEMENT OF LARGE LOW PRESSURE SYSTEM AFFECTING EAST COAST
EARLY IN THE PERIOD. IN FACT...APPEARS SYSTEM NOW TRENDING TOWARD
CUTOFF STATUS AND WILL SLOWLY WEAKEN OVER THE EAST COAST THRU THE
WEEKEND. OTHER MEDIUM RANGE GUIDANCE INCLUDING GFS AND GEM TRENDING
IN THIS DIRECTION. AS A RESULT...UPSTREAM LONG WAVE RIDGE OVER
CENTRAL CONUS INCLUDING WRN GTLAKES WL PERSIST A LITTLE LONGER...AT
LEAST THRU SAT. RIDGE LOOKS TO FINALLY SUCCUMB TO INTENSIFYING SHORT
WAVE FROM THE WRN CONUS LATE IN THE WEEKEND INTO MONDAY. HENCE BEST
THREAT FOR LIQUID PRECIP SUN NGT INTO MON. 925H TEMPS WARM FROM
AROUND -4C ON WED TO FLUCTUATE BTWN 2 AND 6C FROM THU THRU SUN.
LACK OF SNOW COVER HELPS...HOWEVER PENDING CLOUDS...DAYTIME TEMPS
LIKELY TO PEAK MOSTLY IN THE 40S...BEGINNING FRI.
ONE MINOR CONCERN EARLY IN THE PERIOD IS WHETHER ANY LAKE EFFECT
WOULD BE POSSIBLE AS CENTER OF HIGH PRESSURE PASSES BY TO THE NORTH.
ECMWF SHOWING MORE FAVORABLE ONSHORE FLOW IN THE LOW LEVELS WED NGT
BUT THEN BECOMES MORE NLY THU AND EVENTUALLY BACKS TO THE WEST TO
SOUTHWEST. DELTA-T LOOKS MARGINAL WED NGT SO WL HOLD OFF ON ANY
LAKE EFFECT PRECIP AT THIS TIME.
&&
.AVIATION/00Z TAFS/...
QUIET WEATHER CONTINUES INTO THIS EVENING...WITH MIDDLE TO HIGH
CLOUDS AND SOUTHEAST WINDS.
LIGHT SNOW AND LIGHT SLEET WILL MOVE THROUGH TAF SITES LATER TONIGHT
INTO EARLY MONDAY MORNING. MADISON SHOULD SEE THE PRECIPITATION
BETWEEN 07Z AND 08Z MONDAY...AND THE EASTERN TAF SITES BETWEEN 09Z
AND 10Z MONDAY. VISIBILITIES BELOW ALTERNATE MINIMUMS ARE
EXPECTED...WITH CEILINGS IN THE MVFR/IFR CATEGORY.
EXPECTING ABOUT A 4 TO 5 HOUR TIME PERIOD OF THIS LIGHT SNOW AND
LIGHT SLEET MIX...ENDING BY 14Z TO 15Z MONDAY. 1.0 TO 1.5 INCHES ARE
FORECAST AT MADISON...WITH 0.5 TO 1.0 INCH AT THE EASTERN SITES.
HOURLY RATES OF SNOW AND SLEET ACCUMULATION SHOULD RANGE FROM ABOUT
0.1 TO 0.3 INCHES. SOME LIGHT FREEZING RAIN MAY MIX IN AS WELL...BUT
LEFT OUT OF TAFS FOR NOW DUE TO LOWER CONFIDENCE.
AFTER THE MIX OF PRECIPITATION MOVES OUT OF THE AREA...THERE MAY BE
SOME LIGHT RAIN AND LIGHT SNOW LINGERING THROUGH THE REST OF THE
DAY. MVFR VISIBILITIES WITH CEILINGS BELOW ALTERNATE MINIMUMS ARE
ANTICIPATED. ANY ACCUMULATIONS LATER ON MONDAY WOULD BE A DUSTING AT
BEST. WINDS WILL GRADUALLY VEER FROM SOUTHWEST TO WEST.
&&
.MARINE...
TIGHTENING PRESSURE GRADIENT AHEAD OF APPROACHING SFC LOW PRESSURE
TROF WILL RESULT IN CONTINUED GUSTY SOUTHEAST WINDS TURNING TO THE
SOUTH TONIGHT INTO MONDAY. A LULL IN THE WINDS IS EXPECTED LATER
MON INTO MON EVE AS THE SFC TROF MOVES ACROSS THE NEAR SHORE WATERS.
EXPECT THE WINDS TO INCREASE ONCE AGAIN FROM THE NORTHWEST BEHIND
THE TROF MON NGT AS SOMEWHAT COLDER AIR SWEEPS ACROSS LAKE MICHIGAN
AND HIGH PRESSURE BUILDS INTO THE UPPER MIDWEST. HENCE STATUS QUO
ON ONGOING SMALL CRAFT ADVY THRU TUE.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 6 PM CST TUESDAY FOR LMZ643>646.
$$
TONIGHT AND MONDAY/AVIATION...WOOD
MONDAY NIGHT THROUGH SUNDAY/MARINE...MBK
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
221 PM CST SUN DEC 7 2014
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 221 PM CST SUN DEC 7 2014
WATER VAPOR SATELLITE IMAGERY SHOWING THE LEAD SHORT WAVE TROUGH
WAS WORKING ACROSS WESTERN MINNESOTA AND IOWA EARLY THIS
AFTERNOON. THE 07.12Z NAM AND GFS ALONG WITH THE 07.15Z RAP IN
PRETTY GOOD AGREEMENT IN SHOWING THIS WAVE BREAKING INTO TWO PARTS
AS THE AFTERNOON CONTINUES. THE NORTHERN PART OF THE WAVE EITHER
DISSIPATES AHEAD OF THE UPPER LEVEL LOW OVER NORTH DAKOTA OR MOVES
NORTHEAST TOWARD LAKE SUPERIOR. THE SOUTHERN PART OF THE WAVE IS
EXPECTED TO CONTINUE MOVING EAST/SOUTHEAST BUT GOING SOUTH OF THE
AREA ACROSS IOWA AND MISSOURI. AS THIS OCCURS...THE LINE OF RADAR
RETURNS TO THE WEST OF THE AREA IS EXPECTED TO GRADUALLY WEAKEN
AND IS NOT EXPECTED TO PRODUCE MUCH IF ANY PRECIPITATION...BUT
SHOULD HELP TO MOISTEN THE COLUMN. IT NOW APPEARS AS IF THE MAIN
PRECIPITATION BAND WILL OCCUR AHEAD OF THE SECOND AND STRONGER
SHORT WAVE TROUGH ROTATING AROUND THE UPPER LEVEL LOW. THE WAVE
WILL COME ACROSS CENTRAL AND NORTHERN MINNESOTA THIS EVENING AND
NORTHERN MINNESOTA OVERNIGHT. THIS WAVE SHOULD PRODUCE MODERATE
PV ADVECTION IN THE 500-300 MB LAYER AS IT COMES ACROSS THE REGION
WITH WEAK QG CONVERGENCE IN THE 1000-300 MB LAYER.
ISENTROPICALLY...THERE SHOULD BE 2 TO 3 UBAR/S OF UP GLIDE
OCCURRING ON THE 290K SURFACE. THIS SHOULD BE ENOUGH FORCING TO
PRODUCE A BAND OF LIGHT PRECIPITATION AHEAD OF THE SHORT WAVE
TROUGH AND WILL CONTINUE TO SHOW A BAND OF 60 TO 90 PERCENT
CHANCES WORKING WEST TO EAST ACROSS THE AREA TONIGHT. THE BIG
CONCERN WITH THIS PRECIPITATION IS WHAT TYPE IT WILL BE. THE
BUFKIT SOUNDINGS FROM BOTH THE NAM AND GFS CONTINUE TO SHOW A WARM
LAYER ALOFT WILL BE IN PLACE AS THE PRECIPITATION COMES IN TO
PRODUCE EITHER TOTAL OR PARTIAL MELTING FOR EITHER SOME FREEZING
DRIZZLE OR SLEET. EVAPORATIVE COOLING SHOULD WIPE OUT THIS WARM
LAYER WITHIN A COUPLE OF HOURS FOR A TRANSITION OVER TO LIGHT
SNOW. HOWEVER...THIS LIKELY WILL NOT CONTINUE VERY LONG BEFORE
THERE IS A LOSS OF ICE REINTRODUCING THE CHANCE FOR SOME FREEZING
DRIZZLE. THE ICE IN THE CLOUDS SHOULD MAINTAIN ITSELF LONGER OVER
THE NORTHERN SECTIONS TO KEEP THE PRECIPITATION AS LIGHT SNOW
UNTIL THE OVERNIGHT HOURS BEFORE POSSIBLY MIXING WITH SOME
FREEZING DRIZZLE. FORTUNATELY...WITH ONLY LIGHT PRECIPITATION
EXPECTED...ONLY SOME VERY LIGHT ICING MAY OCCUR. THE OTHER THING
THAT MAY MITIGATE THE ICING IS THE POTENTIAL FOR SURFACE
TEMPERATURES TO RISE AND REACH FREEZING OR ABOVE FOR AREAS
SOUTHWEST OF INTERSTATE 94. AT THIS POINT...DO NOT PLAN TO ISSUE A
WINTER WEATHER ADVISORY...BUT WILL SEND OUT A SPECIAL WEATHER
STATEMENT TO HEIGHTEN THE AWARENESS ALONG WITH A SHORT TERM
GRAPHIC CAST IMAGE.
A SECONDARY SHORT WAVE TROUGH WILL ROTATE AROUND THE UPPER LEVEL
LOW MONDAY AND PRODUCE WEAK PV ADVECTION IN THE 500-300 MB LAYER.
SOME WEAK QG CONVERGENCE SHOULD OCCUR IN THE 850-500 MB LAYER
ALONG WITH ABOUT 1 UBAR/S OF UP GLIDE ON THE 290K ISENTROPIC
SURFACE. THIS SHOULD BE ENOUGH TO MAINTAIN A CHANCE FOR SOME LIGHT
PRECIPITATION...ESPECIALLY IN THE INTERSTATE 94 CORRIDOR AND WILL
START THE DAY WITH 60 TO 70 PERCENT CHANCES GRADUALLY DECREASING
THROUGH THE DAY AS THE UPPER LEVEL LOW AND SHORT WAVE TROUGH MOVE
AWAY FROM THE AREA. STILL A CONCERN AS TO WHETHER THERE WILL BE
ICE IN THE CLOUDS AND WILL START WITH A LIGHT SNOW/FREEZING
DRIZZLE GOING TO EITHER FREEZING DRIZZLE OR DRIZZLE BASED ON
SURFACE TEMPERATURES. SOUTHWEST OF THIS AREA...THE LOW LEVEL LAPSE
RATES WILL BE INCREASING WITH VALUES OF 7 TO 10 KM/C BELOW 850 MB
BY AFTERNOON. THIS LOW LEVEL LAYER LOOKS TO BE SATURATED AND WITH
THE CYCLONIC FLOW...THERE SHOULD BE ENOUGH FORCING TO RING OUT
SOME LIGHT PRECIPITATION. FOR NOW...HAVE STAYED WITH FLURRIES AS
THE COLD AIR ADVECTION INCREASES...BUT CONCERNED THIS LAYER MAY
NOT BE COLD ENOUGH FOR ICE TO BE IN THE CLOUDS.
.LONG TERM...(WEDNESDAY THROUGH SUNDAY)
ISSUED AT 221 PM CST SUN DEC 7 2014
RELATIVELY QUIET PERIOD EXPECTED AS HIGH PRESSURE SETS UP OVER THE
UPPER MIDWEST AND THEN REMAINS IN PLACE THROUGH THE END OF THE
WEEK. BOTH THE 07.12Z ECMWF AND GFS SHOW THE RIDGING WILL BEGIN TO
MOVE EAST OF THE REGION OVER THE UP COMING WEEKEND...BUT IT
REMAINS TO BE SEEN HOW FAST THIS WILL OCCUR. THE GFS IS QUICKER TO
DO THIS THAN EITHER THE ECMWF OR 07.12Z GEM. THE FASTER GFS THEN
ALLOWS A SHORT WAVE TROUGH TO COME OUT OF THE DEVELOPING SOUTHWEST
FLOW FOR SOME PRECIPITATION CHANCES SATURDAY NIGHT INTO SUNDAY.
WITH TEMPERATURES WARMING IN THE SOUTHWEST FLOW...THE BULK OF ANY
PRECIPITATION THAT FALLS MAY JUST BE RAIN.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1148 AM CST SUN DEC 7 2014
STRONG 900 TO 800 MB FRONTOGENESIS IS PRODUCING RADAR ECHOES ALONG
THE INTERSTATE 35 CORRIDOR. HOWEVER NOT SEEING ANY PRECIPITATION
ASSOCIATED WITH THIS FORCING AT THE MOMENT. DURING THE NEXT 2 TO 3
HOURS THIS WILL MOVE EAST INTO SOUTHEAST MINNESOTA AND NORTHEAST
IOWA AND WEAKEN. MEANWHILE THE PRECIPITATION WILL HAVE TO WAIT FOR
THE SHORT WAVE MOVING OUT OF THE DAKOTAS. THIS WAVE WILL MOVE
THROUGH SOUTHEAST MINNESOTA AND NORTHEAST IOWA PRIMARILY THIS
EVENING...AND WESTERN WISCONSIN OVERNIGHT. PRECIPITATION WILL
START OUT AS A SNOW OR SLEET...AND THEN TRANSITION POSSIBLY TO A
DRIZZLE OR FREEZING DRIZZLE DEPENDING ON THE TEMPERATURES. ONE
CONCERN DURING THE LATTER IS THAT THE LIFT IS MAINLY ABOVE THE
SATURATED LOW LAYERS...SO WILL IT DEVELOP OR NOT. CONFIDENCE WAS
NOT HIGH ENOUGH TO INCLUDE DRIZZLE/FREEZING DRIZZLE IN THE TAFS AT
THIS TIME.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...04
LONG TERM...04
AVIATION...BOYNE