Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 11/16/14
AREA FORECAST DISCUSSION
NWS TUCSON AZ
830 PM MST SAT NOV 15 2014
.SYNOPSIS...A WEATHER SYSTEM MOVING IN FROM THE NORTH WILL RESULT IN
A CHANCE OF VALLEY RAIN SHOWERS AND MOUNTAIN SNOW MAINLY NORTHEAST
OF TUCSON SUNDAY ALONG WITH GUSTY NORTHWEST WINDS AT TIMES. THIS
SYSTEM WILL BE FOLLOWED BY COOLER THAN AVERAGE TEMPERATURES FOR THE
FIRST HALF OF THE WORK WEEK WITH SOME BELOW FREEZING READINGS BOTH
MONDAY AND TUESDAY MORNINGS.
&&
.DISCUSSION...A BREAK IN MOISTURE WITH THE 00Z KTWC SOUNDING DOWN TO
1/2 INCH PRECIPITABLE WATER AND DECENT CLEARING ACROSS MOST OF
SOUTHEAST ARIZONA. COLD FRONT PUSHING INTO NORTHERN ARIZONA THIS
EVENING AND STILL EXPECTED TO HAVE ENOUGH MOMENTUM TO PUSH SOLIDLY
THROUGH ARIZONA OVER THE NEXT 24 TO 36 HOURS. COLD AIR BEHIND THE
FRONT WITH COLDEST OVERNIGHT LOWS OF THE SEASON SLATED FOR EARLY
THIS WEEK. HARD FREEZE POSSIBLE IN COLDER EASTERN VALLEY LOCATIONS
INCLUDING COCHISE COUNTY...ESPECIALLY MONDAY NIGHT INTO TUESDAY
MORNING.
MINOR FORECAST ADJUSTMENTS BLENDING 00Z NAMDNG5 AND HRRR TRENDS INTO
THE CURRENT FORECAST. THIS INCLUDES BRINGING THE SNOW SHOWERS INTO
EAST CENTRAL MOUNTAINS ABOUT 3 HOURS EARLIER IN THE MORNING. PLEASE
SEE PREVIOUS DISCUSSION BELOW FOR ADDITIONAL DETAILS.
&&
.AVIATION...VALID THRU 17/03Z.
SOME CLOUD INCREASE AHEAD OF AND WITH A COLD FRONT PUSHING
THROUGH THE STATE SUNDAY. AFTER 16/10Z...SCT-BKN CLOUDS AT 5-9K FT
AGL MAINLY EAST OF KTUS. ISOLATED TO SCATTERED VALLEY -SHRA
ESPECIALLY NE OF KSAD WITH MOUNTAIN SNOW LIKELY NE OF KSAD. SURFACE
WINDS INCREASING AFTER 16/15Z...WLY/NWLY SURFACE WIND AT 10-20 KTS
WITH THE STRONGEST EAST OF KTUS...ESPECIALLY IN THE GILA RIVER
VALLEY IN THE VICINITY OF KSAD. AVIATION DISCUSSION NOT UPDATED FOR
TAF AMENDMENTS.
&&
.FIRE WEATHER...A FALL WEATHER SYSTEM WILL BRING ISOLATED TO
SCATTERED VALLEY SHOWERS MAINLY NORTHEAST OF TUCSON SUNDAY WITH
MOUNTAIN SNOW LIKELY IN THE WHITE MOUNTAINS. GUSTY WEST TO NORTHWEST
WINDS DEVELOPING IN THE EASTERN HALF OF THE FORECAST AREA.
ESPECIALLY AROUND SAFFORD WHERE WIND SPEEDS OF 15-25 MPH WITH GUSTS
TO AROUND 30 MPH ARE POSSIBLE IN THE GILA RIVER VALLEY. EASTERLY
WINDS WILL THEN OCCUR OVERNIGHT SUNDAY AND THROUGH THE DAY MONDAY
AND GUSTY AT TIMES. AFTER SUNDAY...DRY CONDITIONS WILL PREVAIL
THROUGH LATE NEXT WEEK WITH BELOW AVERAGE TEMPERATURES.
&&
.PREV DISCUSSION...GORGEOUS DAY FOR OUTDOOR ACTIVITIES ACROSS SE AZ.
THE CLOUD COVER THAT WAS OVER PINAL/SANTA CRUZ/COCHISE COUNTIES THIS
MORNING HAS PUSHED ON EAST WITH SOME PATCHES OF LOWER LEVEL CLOUDS
NEAR THE HIGHER TERRAIN. HIGHS TODAY HAVE BEEN RUNNING 3-5 DEGREES
COOLER THAN FRIDAY.
THE EVENING WILL START OFF MOSTLY CLEAR BUT CLOUD COVER WILL BE ON
THE INCREASE IN ADVANCE OF UPPER LEVEL TROF AND ITS ASSOCIATED COLD
FRONT. THIS COLD FRONT...WITH LIGHT PRECIPITATION...WAS PUSHING
THROUGH NRN UTAH/NRN NEVADA THIS AFTERNOON AND WILL CONTINUE TO SAG
SOUTH OVER THE NEXT 24 HOURS INTO AND THROUGH ARIZONA. BEST CHANCES
OF PRECIP WILL BE NE OF TUCSON BETWEEN MIDNIGHT AND NOON SUNDAY.
COULD SEE LIGHT SPRINKLES FROM TUCSON WEST FOR A BRIEF TIME SUNDAY
MORNING. SNOW LEVELS LOWERING INTO THE 6K-7.5K FT NE OF TUCSON WITH
LESS THAN AN INCH OF SNOW AT THIS HIGHEST ELEVATIONS...ESPECIALLY IN
THE WHITES. COOLER SUNDAY WITH GUSTY NW WINDS...STRONGEST IN NW-SE
ORIENTED VALLEYS.
MAIN CONCERN AFTER SUNDAY WILL BE THE MUCH COLDER AIR MASS THAT WILL
BE OVER THE AREA WITH FREEZING TEMPERATURES LIKELY FOR A GOOD CHUNK
OF LOWER ELEVATION AREAS EAST OF TUCSON. HAVE DECIDED TO HOIST A
FREEZE WATCH FOR BOTH MONDAY AND TUESDAY MORNING FOR EASTERN
PINAL...GRAHAM...SRN GREENLEE AND COCHISE COUNTIES. TUESDAY COULD BE
THE COLDEST OF THE TWO DAYS...ESPECIALLY IN COCHISE COUNTY.
THE REMAINDER OF THE WEEK WILL SEE NEAR NORMAL HIGH TEMPERATURES
WITH OVERNIGHT LOWS RECOVERING FROM THE EARLY WEEK COLD SNAP. THERE
AREA SOME FORECAST ISSUES LATE IN THE EXTENDED CONCERN STRONGER
PACIFIC TROF MOVING THROUGH THE DESERT SW. GFS MORE PROGRESSIVE THAN
THE WETTER ECMWF WITH THE ECMWF HAVE A STRONGER UPPER JET MOVING
ACROSS THE NORTH PACIFIC. FOR NOW LEANED TOWARD THE DRIER GFS SINCE
ITS SEVEN DAYS OUT. THIS MOST LIKELY WILL CHANGE AS TIME FRAME GETS
CLOSER.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...
FREEZE WATCH FROM 2 AM TO 8 AM MONDAY MORNING FOR AZZ506>509.
FREEZE WATCH FROM 2 AM TO 8 AM TUESDAY MORNING FOR AZZ506>509.
&&
$$
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MEYER/GLUECK
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
900 AM MST FRI NOV 14 2014
.SYNOPSIS...
A WEAK LOW PRESSURE SYSTEM WILL BRING AN INCREASE IN CLOUDS TO THE
REGION TODAY WITH PRECIPITATION MAINLY CONFINED TO NORTHERN ARIZONA.
A STRONGER STORM SYSTEM WILL MOVE THROUGH THE REGION
SUNDAY...BRINGING AN INCREASE IN WIND ALONG WITH A SLIGHT CHANCE OF
SHOWERS EAST OF PHOENIX. COOLER AND DRIER CONDITIONS ARE ANTICIPATED
MONDAY BEHIND A COLD FRONT. TEMPERATURES WILL REBOUND TUESDAY TO
AROUND NORMAL AND CONTINUE THROUGH NEXT WEEK.
&&
.DISCUSSION...
EXTENSIVE THICK MID/HIGH CLOUD COVER CONTINUES TO PROPAGATE INTO THE
FORECAST AREA THIS MORNING AHEAD OF A SHEARED WAVE APPROACHING THE
SRN CALIFORNIA COASTLINE. 12Z REGIONAL SOUNDING DATA STILL SHOWED A
NOTABLE WARM DRY NOSE IN THE H8-H5 LAYER SUCH THAT SOME VIRGA MAY BE
SEEN TODAY...BUT ANY PRECIPITATING WILL BE RELEGATED TO NRN ARIZONA
HIGHER TERRAIN. THIS CLOUD COVER MAY ACT TO PARTIALLY INHIBIT FULL
INSOLATION AND MIXING THIS AFTERNOON...AND THIS SEEMED TO BE
ACCOUNTED FOR ALREADY. THUS...ONLY MINOR CHANGES TO CAPTURE SHORT
TERM TRENDS WERE NEEDED THIS MORNING.
&&
.PREVIOUS DISCUSSION...
/315 AM MST FRI NOV 14 2014/
HIGH CLOUDS CONTINUE TO SPREAD EASTWARD THIS MORNING AHEAD OF AN
ADVANCING SHORT-WAVE TROUGH OFF THE CA COAST. MODEL CROSS SECTIONS
INDICATE THAT CLOUDS WILL LOWER AND THICKEN THROUGHOUT THE DAY.
HOWEVER...GUIDANCE INCLUDING THE HI-RES HRRR IS IN GOOD
AGREEMENT THAT PRECIPITATION WILL REMAIN CONFINED TO MAINLY NORTHERN
AZ...ASSOCIATED WITH MODEST JET-FORCED ASCENT. MEANWHILE...ABOVE
AVERAGE TEMPERATURES WILL PERSIST WITH HIGHS IN THE UPPER 70S IN THE
LOWER DESERTS.
OTHER THAN A DECREASE IN CLOUDINESS...LITTLE CHANGE IN SENSIBLE
WEATHER CONDITIONS IS ANTICIPATED SATURDAY. OVERALL PATTERN ACROSS
THE WESTERN CONUS WILL AMPLIFY SUNDAY AS A RIDGE IN THE EASTERN
PACIFIC CONSOLIDATES WITH THE ERSTWHILE YUKON BLOCK AND A SHORT-WAVE
TROUGH DROPS SOUTHEASTWARD THROUGH THE GREAT BASIN TOWARDS THE FOUR
CORNERS. AT THE SURFACE...A COLD FRONT WILL SLIDE SOUTHWARD THROUGH
AZ...WITH A NOTICEABLE INCREASE IN WIND SUNDAY
AFTERNOON...PARTICULARLY DOWN THE CO RIVER VALLEY WHERE GUSTS MAY
APPROACH 35-40 MPH. LATEST DOWNSCALED NAM AND ECMWF ALSO SUGGEST AN
INCREASED THREAT OF SHOWERS ACROSS THE HIGHER TERRAIN EAST OF
PHOENIX AND POPS WERE NUDGED UPWARDS TO AROUND 20 PERCENT EAST OF
GLOBE.
A COLDER AIR MASS BEHIND THE FRONT WILL SETTLE ACROSS THE REGION
MONDAY...MARKING THE COOLEST AIR OF THE SEASON AND THE FIRST DAY IN
ROUGHLY TWO WEEKS OF BELOW NORMAL TEMPERATURES. GFS/ECMWF ALSO
INDICATE STRONG SUBSIDENCE IN A NORTHWESTERLY FLOW RESULTING IN
SIGNIFICANT DRYING BY MONDAY AFTERNOON WITH SURFACE DEWPOINTS
DROPPING INTO THE LOW TEENS OR EVEN SINGLE DIGITS.
OPERATIONAL GFS/ECMWF REMAIN IN VERY GOOD AGREEMENT THROUGH NEXT
WEEK...DEPICTING THE AFOREMENTIONED RIDGE MIGRATING EAST WHILE
WEAKENING ACROSS THE INTERMOUNTAIN WEST. ZONAL FLOW WILL
CONSEQUENTLY REDEVELOP ACROSS THE DESERT SOUTHWEST...RESULTING IN
OCCASIONAL PERIODS OF HIGH CLOUDS. BIAS-CORRECTED ECMWF ENSEMBLE MOS
HAS BEEN A TOP PERFORMER THE PAST TWO WEEKS AND TEMPERATURES WERE
WEIGHTED HEAVILY TOWARDS THIS DATASET...YIELDING A SLIGHT DECREASE
FROM THE PREVIOUS FORECAST.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...AND
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
WESTERLY FLOW ALOFT IS EXPECTED TO CONTINUE TO BRING SCT-BKN
MID-HIGH CLOUDS LAYERS OVER THE TERMINALS THROUGH THE TAF PERIOD.
WEAK SFC PRESSURE GRADIENTS TO KEEP WINDS MAINLY ON THE LIGHT
SIDE...AOB 10 KTS...WITH THE USUAL DIURNAL TRENDS IN DIRECTION AND
SPEED.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
SUNDAY THROUGH THURSDAY...
A COLD FRONT MOVING SOUTHWARD INTO THE DESERT SOUTHWEST ON SUNDAY IS
EXPECTED TO BRING GUSTY NORTHERLY TO NORTHEASTERLY WINDS TO THE
REGION...WITH THE STRONGEST WINDS BLOWING DOWN THE LOWER COLORADO
RIVER VALLEY...WHERE NORTHERLY GUSTS TO 40 MPH ARE POSSIBLE AT A FEW
SPOTS. THIS FRONT IS EXPECTED TO REMAIN DRY AT MOST
LOCATIONS...EXCEPT PERHAPS A FEW SPRINKLES OR LIGHT SHOWERS
OCCURRING OVER THE HIGHER TERRAIN EAST OF PHOENIX. MUCH LIGHTER
WINDS ARE EXPECTED FROM MONDAY ONWARD INTO THURSDAY. MUCH DRIER AND
COOLER AIR BEHIND THE AFOREMENTIONED COLD FRONT WILL ALSO PUSH
MINIMUM HUMIDITIES DOWN FROM THE TEENS AND 20S ON SUNDAY INTO THE
SINGLE DIGITS-TEENS ON MONDAY AND TUESDAY...WITH A RECOVERY BACK
INTO THE TEENS AND 20S EXPECTED ON WEDNESDAY AND THURSDAY. POOR
OVERNIGHT HUMIDITY RECOVERIES ON SUNDAY AND MONDAY NIGHT WILL BECOME
FAIR TO GOOD BY WEDNESDAY AND THURSDAY NIGHT.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...MO/HIRSCH
AVIATION...PERCHA
FIRE WEATHER...PERCHA
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
315 AM MST FRI NOV 14 2014
.SYNOPSIS...
A WEAK LOW PRESSURE SYSTEM WILL BRING AN INCREASE IN CLOUDS TO THE
REGION TODAY WITH PRECIPITATION MAINLY CONFINED TO NORTHERN ARIZONA.
A STRONGER STORM SYSTEM WILL MOVE THROUGH THE REGION
SUNDAY...BRINGING AN INCREASE IN WIND ALONG WITH A SLIGHT CHANCE OF
SHOWERS EAST OF PHOENIX. COOLER AND DRIER CONDITIONS ARE ANTICIPATED
MONDAY BEHIND A COLD FRONT. TEMPERATURES WILL REBOUND TUESDAY TO
AROUND NORMAL AND CONTINUE THROUGH NEXT WEEK.
&&
.DISCUSSION...
HIGH CLOUDS CONTINUE TO SPREAD EASTWARD THIS MORNING AHEAD OF AN
ADVANCING SHORT-WAVE TROUGH OFF THE CA COAST. MODEL CROSS SECTIONS
INDICATE THAT CLOUDS WILL LOWER AND THICKEN THROUGHOUT THE DAY.
HOWEVER...GUIDANCE INCLUDING THE HI-RES HRRR IS IN GOOD
AGREEMENT THAT PRECIPITATION WILL REMAIN CONFINED TO MAINLY NORTHERN
AZ...ASSOCIATED WITH MODEST JET-FORCED ASCENT. MEANWHILE...ABOVE
AVERAGE TEMPERATURES WILL PERSIST WITH HIGHS IN THE UPPER 70S IN THE
LOWER DESERTS.
OTHER THAN A DECREASE IN CLOUDINESS...LITTLE CHANGE IN SENSIBLE
WEATHER CONDITIONS IS ANTICIPATED SATURDAY. OVERALL PATTERN ACROSS
THE WESTERN CONUS WILL AMPLIFY SUNDAY AS A RIDGE IN THE EASTERN
PACIFIC CONSOLIDATES WITH THE ERSTWHILE YUKON BLOCK AND A SHORT-WAVE
TROUGH DROPS SOUTHEASTWARD THROUGH THE GREAT BASIN TOWARDS THE FOUR
CORNERS. AT THE SURFACE...A COLD FRONT WILL SLIDE SOUTHWARD THROUGH
AZ...WITH A NOTICEABLE INCREASE IN WIND SUNDAY
AFTERNOON...PARTICULARLY DOWN THE CO RIVER VALLEY WHERE GUSTS MAY
APPROACH 35-40 MPH. LATEST DOWNSCALED NAM AND ECMWF ALSO SUGGEST AN
INCREASED THREAT OF SHOWERS ACROSS THE HIGHER TERRAIN EAST OF
PHOENIX AND POPS WERE NUDGED UPWARDS TO AROUND 20 PERCENT EAST OF
GLOBE.
A COLDER AIR MASS BEHIND THE FRONT WILL SETTLE ACROSS THE REGION
MONDAY...MARKING THE COOLEST AIR OF THE SEASON AND THE FIRST DAY IN
ROUGHLY TWO WEEKS OF BELOW NORMAL TEMPERATURES. GFS/ECMWF ALSO
INDICATE STRONG SUBSIDENCE IN A NORTHWESTERLY FLOW RESULTING IN
SIGNIFICANT DRYING BY MONDAY AFTERNOON WITH SURFACE DEWPOINTS
DROPPING INTO THE LOW TEENS OR EVEN SINGLE DIGITS.
OPERATIONAL GFS/ECMWF REMAIN IN VERY GOOD AGREEMENT THROUGH NEXT
WEEK...DEPICTING THE AFOREMENTIONED RIDGE MIGRATING EAST WHILE
WEAKENING ACROSS THE INTERMOUNTAIN WEST. ZONAL FLOW WILL
CONSEQUENTLY REDEVELOP ACROSS THE DESERT SOUTHWEST...RESULTING IN
OCCASIONAL PERIODS OF HIGH CLOUDS. BIAS-CORRECTED ECMWF ENSEMBLE MOS
HAS BEEN A TOP PERFORMER THE PAST TWO WEEKS AND TEMPERATURES WERE
WEIGHTED HEAVILY TOWARDS THIS DATASET...YIELDING A SLIGHT DECREASE
FROM THE PREVIOUS FORECAST.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...AND
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
WESTERLY FLOW ALOFT IS EXPECTED TO CONTINUE TO BRING SCT-BKN
MID-HIGH CLOUDS LAYERS OVER THE TERMINALS THROUGH THE TAF PERIOD.
WEAK SFC PRESSURE GRADIENTS TO KEEP WINDS MAINLY ON THE LIGHT
SIDE...AOB 10 KTS...WITH THE USUAL DIURNAL TRENDS IN DIRECTION AND
SPEED.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
SUNDAY THROUGH THURSDAY...
A COLD FRONT MOVING SOUTHWARD INTO THE DESERT SOUTHWEST ON SUNDAY IS
EXPECTED TO BRING GUSTY NORTHERLY TO NORTHEASTERLY WINDS TO THE
REGION...WITH THE STRONGEST WINDS BLOWING DOWN THE LOWER COLORADO
RIVER VALLEY...WHERE NORTHERLY GUSTS TO 40 MPH ARE POSSIBLE AT A FEW
SPOTS. THIS FRONT IS EXPECTED TO REMAIN DRY AT MOST
LOCATIONS...EXCEPT PERHAPS A FEW SPRINKLES OR LIGHT SHOWERS
OCCURRING OVER THE HIGHER TERRAIN EAST OF PHOENIX. MUCH LIGHTER
WINDS ARE EXPECTED FROM MONDAY ONWARD INTO THURSDAY. MUCH DRIER AND
COOLER AIR BEHIND THE AFOREMENTIONED COLD FRONT WILL ALSO PUSH
MINIMUM HUMIDITIES DOWN FROM THE TEENS AND 20S ON SUNDAY INTO THE
SINGLE DIGITS-TEENS ON MONDAY AND TUESDAY...WITH A RECOVERY BACK
INTO THE TEENS AND 20S EXPECTED ON WEDNESDAY AND THURSDAY. POOR
OVERNIGHT HUMIDITY RECOVERIES ON SUNDAY AND MONDAY NIGHT WILL BECOME
FAIR TO GOOD BY WEDNESDAY AND THURSDAY NIGHT.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
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DISCUSSION...HIRSCH
AVIATION...PERCHA
FIRE WEATHER...PERCHA
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
921 AM PST FRI NOV 14 2014
.SYNOPSIS...PARTLY CLOUDY AND DRY CONDITIONS ARE EXPECTED THROUGH THE
WEEKEND WITH SEASONABLE TEMPERATURES. SOME DRIER OFFSHORE WINDS
MAY DEVELOP SUNDAY AND MONDAY LEADING TO A WARMING AND DRYING
TREND AS HIGH PRESSURE BUILDS. THE NEXT PACIFIC FRONT LOOKS TO
ARRIVE LATE TUESDAY INTO WEDNESDAY WITH A CHANCE OF SOME LIGHT
RAIN.
&&
.DISCUSSION...AS OF 9:20 AM PST FRIDAY...SATELLITE IMAGERY SHOWS
PATCHY CLOUDS AND/OR FOG OVER PORTIONS OF THE AREA. SURFACE
OBSERVATIONS STILL INDICATE A FEW AREAS REPORTING DENSE
FOG...MAINLY JUST SANTA ROSA. THE DENSE FOG ADVISORY FOR THE NORTH
BAY VALLEYS WAS ALLOWED TO EXPIRE AT 9 AM. MOSTLY SUNNY CONDITIONS
TODAY WILL ALLOW HIGH TEMPS TO REACH THE MID TO UPPER 60S IN MOST
AREAS.
THERE COULD BE A REPEAT OF FOG OVERNIGHT TONIGHT...OTHERWISE IT IS
EXPECTED TO BE A MILD WEEKEND WITH DRY CONDITIONS AND LIGHT
OFFSHORE FLOW BY SUNDAY MORNING. THE LATEST RUN OF THE NAM12 GIVES
30 KNOT WINDS AT THE 925 MB LEVEL TO AREAS IN THE NORTH AND EAST
BAY...MAINLY ACROSS THE HIGHEST TERRAIN THERE. THE OFFSHORE
GRADIENT IS PROGGED TO TIGHTEN BY SUNDAY AFTERNOON AND USHER IN A
MUCH DRIER AIR MASS WITH HUMIDITY VALUES DROPPING BY MONDAY. EVEN
WITH OFFSHORE FLOW...THE COLD AIR OVER THE GREAT BASIN WILL RESULT
IN HIGH TEMPERATURES REMAINING IN THE 70S ACROSS THE DISTRICT
THROUGH EARLY NEXT WEEK.
BY TUESDAY THE SURFACE FLOW IS FORECAST TO SWITCH TO ONSHORE AS A
PACIFIC SYSTEM APPROACHES THE COAST. RAIN CHANCES WITH THIS FIRST
SYSTEM ARE PROGGED FOR MAINLY THE NORTH BAY...BUT THERE ARE
DIFFERENCES IN MODEL OUTPUT. LATER NEXT WEEK THERE ARE PERHAPS
BETTER CHANCES FOR RAIN AS A SERIES OF STORMS TAKES AIM AT THE
WEST COAST.
&&
.AVIATION...AS OF 4:00 AM PST FRIDAY...TRICKY FORECAST THIS
MORNING WITH SEVERAL FACTORS AT PLAY. SATELLITE IMAGERY SHOWS HIGH
CLOUDS HAVE NOW PUSHED SOUTH OF ALL TAF SITES RESULTING IN A RACE
AGAINST TIME FOR FOG TO DEVELOP BEFORE SUNRISE. IN THE NORTH
BAY VALLEYS...INCLUDING KSTS AND KAPC...CLEARING SKIES AND LIGHT
WINDS CREATED A FAVORABLE ENVIRONMENT FOR FOG DEVELOPMENT AND
VISBYS ARE 1/4SM OR LESS. AS OF LAST OBSERVATION... KOAK IS
REPORTING CLEAR SKIES AFTER LOW CLOUDS DISSIPATED ... HOWEVER
GOES-W CIG PROBABILITY PRODUCT INDICATES LOW CLOUDS ARE STILL IN
THE VICINITY. KOAK/EAST BAY COULD BE THE NEXT AREA OF FOG
DEVELOPMENT IF WINDS REMAIN CALM AND SKIES REMAIN CLEAR IN THE
VICINITY. LEAST WORRIED ABOUT FOG AT KSFO...HOWEVER CAN NOT RULE
IT OUT WITH HRRR HINTING AT DEVELOPMENT BETWEEN 14-16Z. GRADUAL
CLEARING OF LOW CIGS EXPECTED LATE FRIDAY MORNING WITH VFR
CONDITIONS IN MOST AREAS BY MIDDAY. PATCHY LOW CLOUDS MAY PERSIST
WELL INTO THE AFTERNOON HOURS. OVERALL CONFIDENCE IS LOW AT
KSFO/KOAK... AND MEDIUM TO HIGH ELSEWHERE.
VICINITY OF KSFO... MVFR WITH LOCAL IFR CIGS AND PATCHY FOG
POSSIBLE THROUGH FRIDAY MORNING...MAINLY ON EAST SIDE OF SF BAY
BETWEEN 14-17Z FRI. LOW CIGS WILL LIKELY CLEAR BETWEEN 18-20Z
FRIDAY MORNING.
KSFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...MVFR CIGS WITH BRIEF PATCHY IFR CIGS
POSSIBLE THROUGH EARLY MORNING. VFR CONDITIONS FORECAST TO RETURN
BY LATE MORNING. LIGHT WINDS.
&&
.MARINE...AS OF 08:20 AM PST FRIDAY...NORTHWEST WINDS WILL PREVAIL
ALONG THE CENTRAL COAST TODAY THROUGH THE WEEKEND. A MODERATE WEST
TO NORTHWEST SWELL WILL CONTINUE TO IMPACT THE COASTAL WATERS
THROUGH THE WEEKEND AS WELL. SOUTHERLY WINDS WILL RETURN EARLY
NEXT WEEK AS A STORM SYSTEM APPROACHES THE REGION.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
&&
$$
PUBLIC FORECAST: SIMS
AVIATION: DRP
MARINE: MM
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AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
406 AM PST FRI NOV 14 2014
.SYNOPSIS...DENSE FOG THIS MORNING...MAINLY IN THE NORTH BAY
OTHERWISE PARTLY CLOUDY AND DRY THROUGH THE WEEKEND WITH
SEASONABLE TEMPERATURES. SOME DRIER OFFSHORE WINDS MAY DEVELOP
SUNDAY AND MONDAY LEADING TO A WARMING AND DRYING TREND AS HIGH
PRESSURE BUILDS. THE NEXT PACIFIC FRONT LOOKS TO ARRIVE LATER
TUESDAY INTO WEDNESDAY WITH A CHANCE OF SOME LIGHT RAIN.
&&
.DISCUSSION...AS OF 3:40 AM PST FRIDAY...SHORT TERM FOCUS IS WITH
DENSE FOG IN THE NORTH BAY. NAPA...SANTA ROSA AND PETALUMA HAVE
BEEN REPORTING 1/4 MILE FOG OR LESS MOST OF THE NIGHT SO A DENSE
FOG ADVISORY HAS BEEN ISSUED FOR THE NORTH BAY VALLEYS UNTIL 9 AM
TO COVER THE MORNING COMMUTE HOURS. AS A HIGH CLOUD DECK SHIFTS
SOUTH TOWARDS SOUTHERN CALIFORNIA THE CLEARING SKIES WILL LIKELY
ALLOW SOME MORE AREAS OF DENSE FOG TO DEVELOP THROUGH SUNRISE BUT
FOR NOW THE MOST WIDESPREAD FOG IS OVER THE NORTH BAY.
SKIES SHOULD TURN PARTLY TO MOSTLY SUNNY THIS AFTERNOON WITH MUCH
MORE SUNSHINE COMPARED TO THURSDAY ALLOWING TEMPERATURES TO WARM
INTO THE UPPER 60S FOR MOST OF THE DISTRICT.
WILL HAVE TO MONITOR FOR SOME MORE DENSE FOG POTENTIAL TONIGHT BUT
IN GENERAL THE WEATHER LOOKS DRY AND QUIET THIS WEEKEND. ON
SATURDAY AN INSIDE SLIDER TYPE EVENT WILL DEVELOP OVER EASTERN
OREGON AND BEGIN TO DROP DOWN THE EAST SIDE OF THE SIERRA OVER
NEVADA. THIS WILL KEEP CONDITIONS DRY AND SEASONABLE FOR SATURDAY
AFTERNOON. AS THE FRONT DROPS INTO THE GREAT BASIN ON SUNDAY A
NORTHERLY/OFFSHORE SURFACE GRADIENT WILL DEVELOP. MODELS ARE NOW
SHOWING SOME DRY NORTHEASTERLY 925 MB WINDS BY SUNRISE SUNDAY IN
THE 25 KNOT RANGE. FOR THE MOST PART EXPECT THESE WINDS TO STAY
ABOVE THE RIDGE-LINES OF THE NORTH AND EAST BAY HILLS WITH ONLY
PLACES LIKE MOUNT DIABLO SEEING MUCH WIND OF NOTE.
HOWEVER THE GRADIENT WILL INCREASE BY SUNDAY AFTERNOON AND USHER
IN A MUCH DRIER AIRMASS WITH HUMIDITY VALUES CRASHING LATER SUNDAY
INTO MONDAY. DRY NORTH TO NORTHEAST FLOW CONTINUES ON MONDAY WITH
COLD AIR OVER THE GREAT BASIN...ALLOWING A SANTA ANA TO SET UP
OVER SOCAL. THE BAY AREA SHOULD SEE SUNNY SKIES WITH HUMIDITY
VALUES IN THE TEENS ON MONDAY. EVEN WITH OFFSHORE FLOW THE SOURCE
REGION OF THE AIRMASS IS COLD SO ONLY LOOKING FOR HIGHS IN THE 70S
AS HIGH PRESSURE PEAKS BY MONDAY EVENING.
A PACIFIC FRONT WILL APPROACH ON TUESDAY AS THE FLOW TURNS
ONSHORE. RIGHT NOW IT LOOKS LIKE A CHANCE FOR SOME LIGHT RAIN BY
TUESDAY EVENING INTO EARLY WEDS BUT CONFIDENCE REMAINS LOW GIVEN
THE PATTERN AND POOR MODEL CONSISTENCY.
STILL LOOKS LIKE ANY GOOD CHANCE OF BENEFICIAL RAINS REMAINS IN
THE EXTENDED FORECAST WITH THE MODELS CONTINUING TO HINT AT
STRONGER WESTERLIES BY ABOUT NEXT FRIDAY.
&&
.AVIATION...AS OF 4:00 AM PST FRIDAY...TRICKY FORECAST THIS
MORNING WITH SEVERAL FACTORS AT PLAY. SATELLITE IMAGERY SHOWS HIGH
CLOUDS HAVE NOW PUSHED SOUTH OF ALL TAF SITES RESULTING IN A RACE
AGAINST TIME FOR FOG TO DEVELOP BEFORE SUNRISE. IN THE NORTH
BAY VALLEYS...INLCUDING KSTS AND KAPC...CLEARING SKIES AND LIGHT
WINDS CREATED A FAVORABLE ENVIRONMENT FOR FOG DEVELOPMENT AND
VISBYS ARE 1/4SM OR LESS. AS OF LAST OBSERVATION... KOAK IS
REPORTING CLEAR SKIES AFER LOW CLOUDS DISSIPATED ... HOWEVER
GOES-W CIG PROBABILITY PRODUCT INDICTATES LOW CLOUDS ARE STILL IN
THE VICINITY. KOAK/EAST BAY COULD BE THE NEXT AREA OF FOG
DEVELOPMENT IF WINDS REMAIN CALM AND SKIES REMAIN CLEAR IN THE
VICINITY. LEAST WORRIED ABOUT FOG AT KSFO...HOWEVER CAN NOT RULE
IT OUT WITH HRRR HINTING AT DEVELOPMENT BETWEEN 14-16Z. GRADUAL
CLEARING OF LOW CIGS EXPECTED LATE FRIDAY MORNING WITH VFR
CONDITIONS IN MOST AREAS BY MIDDAY. PATCHY LOW CLOUDS MAY PERSIST
WELL INTO THE AFTERNOON HOURS. OVERALL CONFIDENCE IS LOW AT
KSFO/KOAK... AND MEDIUM TO HIGH ELSEWHERE.
VICINITY OF KSFO... MVFR WITH LOCAL IFR CIGS AND PATCHY FOG
POSSIBLE THROUGH FRIDAY MORNING...MAINLY ON EAST SIDE OF SF BAY
BETWEEN 14-17Z FRI. LOW CIGS WILL LIKELY CLEAR BETWEEN 18-20Z
FRIDAY MORNING.
KSFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...MVFR CIGS WITH BRIEF PATCHY IFR CIGS
POSSIBLE THROUGH EARLY MORNING. VFR CONDITIONS FORECAST TO RETURN
BY LATE MORNING. LIGHT WINDS.
&&
.MARINE...AS OF 03:43 AM PST FRIDAY...GENERALLY WEAK NORTHWEST
FLOW WILL PERSIST ACROSS A MAJORITY OF THE COASTAL WATERS THROUGH
THE WEEKEND. THE EXCEPTION WILL BE OFF THE BIG SUR COAST WITH
MODERATE NORTHWEST WINDS EXPECTED AT TIMES. A DOMINATE WEST TO
NORTHWEST SWELL WILL GRADUALLY DECAY ALONG WITH SHORTENING PERIODS
THROUGH EARLY NEXT WEEK. NEXT SIGNIFICANT SHIFT IN SEAS ARRIVES
TUESDAY TO WEDNESDAY OF NEXT WEEK.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...DENSE FOG ADVISORY...DENSE FOG ADVISORY TIL 9 AM FOR
NORTH BAY VALLEYS.
&&
$$
PUBLIC FORECAST: RWW
AVIATION/MARINE: DRP
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AREA FORECAST DISCUSSION
NWS PUEBLO CO
805 PM MST SAT NOV 15 2014
.UPDATE...
ISSUED AT 759 PM MST SAT NOV 15 2014
MAIN BAND OF HEAVIER SNOW NOW DROPPING INTO EL PASO COUNTY...AND
EXPECT SNOWFALL RATES TO INCREASE WITH A QUICK 2-4 INCHES LIKELY
BY MIDNIGHT. FARTHER SOUTH...HAD TO INCREASE FORECAST SNOW
AMOUNTS SLIGHTLY OVER PUEBLO COUNTY WHERE 1-2 INCHES HAS ALREADY
FALLEN AND 00Z NAM SUGGESTS ANOTHER 2-4 POSSIBLE. MADE ONLY MINOR
ADJUSTMENT ELSEWHERE.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 330 PM MST SAT NOV 15 2014
...WIDESPREAD SNOW TO IMPACT THE REGION TONIGHT...
COLD FRONT HAS ALREADY DROPPED THROUGH SOUTHEAST COLORADO THOUGH
CORE OF COLDER AIR IS STILL SITTING ACROSS NORTHEAST COLORADO AND
NORTHERN EL PASO COUNTY WHERE TEMPERATURES ARE IN THE TEENS (VS. THE
UPPER 20S AND 30S ACROSS THE REMAINDER OF THE SOUTHEAST PLAINS).
MAIN UPPER TROF IS CURRENTLY ACROSS WY/ID AND WILL CONTINUE DROPPING
SOUTHWARD INTO THE 4 CORNERS REGION TONIGHT. UPPER JET ACROSS CO
HAS LED TO SOME BANDED SNOW ACROSS NORTHEAST COLORADO...WITH SOME
PERIODIC LIGHT SNOW CONTINUING ACROSS THE NORTHERN PORTIONS OF
MONUMENT HILL WHERE MOST OF THE FORCING IS LIKELY DUE TO SHALLOW
OROGRAPHICS. SNOW ALSO CONTINUES ALONG THE CONTINENTAL
DIVIDE...THOUGH INTENSITIES HAVE LET UP QUITE A BIT FROM THIS
MORNING. THAT WILL BE CHANGING IN THE NEXT 6 HOURS THOUGH AS
DYNAMICS FROM THE UPPER TROF SHIFTS SOUTHWARD WITH TIME. BEST QG
FORCING APPEARS TO DROP THROUGH THE WESTERN AND SOUTHERN PORTIONS OF
THE FORECAST AREA. CHALLENGES STILL REVOLVE AROUND SNOW AMOUNTS.
MODELS APPEAR TO BE STRUGGLING THE MOST ACROSS THE PIKES PEAK
REGION...WITH GFS PREDICTING A HEALTHY 3-7 INCHES ACROSS THIS
REGION...WHILE NAM12 HAS MORE IN THE 1 TO 3 INCH RANGE. RAP IS
GOING ALONG WITH GFS...WHILE ECMWF AND OTHER HIGH RES MODELS
(ARW..NMM) AGREE MORE WITH THE NAM. SO HAVE TO HUNT FOR CLUES TO
SUGGEST WHERE TO PUT THE NORTHERN EDGE OF THE HEADLINE AREAS. GIVEN
THE TRACK OF THE UPPER FORCING IS FARTHER TO THE SOUTH...AND THE
BEST UPGLIDE OVER THE H7 FRONT SEEMS TO BE MORE ACROSS SOUTHERN
AREAS...HAVE LEFT PIKES PEAK AND EL PASO COUNTY OUT OF THE ADVISORY
AREA FOR NOW. SNOWFALL GRIDS WILL CARRY AROUND 2-5 INCHES WITH
SOUTHERN EL PASO COUNTY MORE IN THE 2 TO 3 INCH RANGE.
WHERE MODELS AGREE BETTER IS ACROSS THE SOUTHEAST MOUNTAINS AND
SOUTHERN I-25 CORRIDOR. HAVE EXPANDED THE ADVISORIES NORTHWARD AND
EASTWARD A TAD. PUEBLO COUNTY IS ALWAYS A CHALLENGE AS HEAVIER
AMOUNTS MAY END UP ACROSS SOUTHERN AND WESTERN PORTIONS OF THE
COUNTY WHILE NORTHEAST PORTIONS SEE MORE IN THE 1-3 INCH RANGE. ALL
THE MODELS SEEM TO HIT THE SOUTHERN SANGRES WITH THE HEAVIEST
AMOUNTS OF QPF...AND THIS LOOKS REASONABLE GIVEN THE TRACK OF THE
SYSTEM. THUS HAVE UPGRADED THE WINTER WEATHER ADVISORY TO A WARNING
FOR THE SOUTHERN SANGRES. HAVE ALSO ADDED EASTERN LAS ANIMAS COUNTY
TO THE ADVISORY WHERE THE NORTHERN SLOPES OF THE RATON WILL HAVE THE
BENEFIT OF SOME NORTHEAST OROGRAPHICS.
WILL HOLD ON TO THE WINTER STORM WARNINGS ALONG THE CONTINENTAL
DIVIDE. THESE AREAS SHOULD PICK UP ANOTHER 5 TO 10 INCHES OVERNIGHT
WITH THE HEAVIEST ACROSS SOUTHERN PORTIONS OF THE EASTERN SAN JUAN
MOUNTAINS.
A COUPLE OTHER CHALLENGING SPOTS INCLUDE THE SAN LUIS VALLEY WHERE
HIGH RES MODELS ARE NOT SHOWING MUCH SNOW. HAVE GONE WITH AROUND AN
INCH TO 1.5 ACROSS THE VALLEY FLOOR GIVEN THIS AREA WILL BE IN
BETTER PROXIMITY TO THE UPPER DYNAMICS. BEST CHANCE WILL COME IN
AFTER 10 PM FOR THIS AREA. BACA COUNTY IS THE FINAL CHALLENGE.
MODEL RUNS WERE SUGGESTING AROUND 2 TO 4 INCHES OUT THAT WAY...JUST
SHY OF ADVISORY CRITERIA...BUT LATEST NAM12 HAS COME IN HEAVIER...SO
THIS AREA MAY HAVE TO BE MONITORED CLOSELY IF THE HEAVIER SNOW BAND
SETS UP ACROSS THAT AREA.
HIGHLIGHTS WILL PARE OFF FROM NORTH TO SOUTH TOWARDS MORNING. MOST
OF THE SNOW WILL BE DONE BY 10Z UP NORTH...AND BY 13-16Z DOWN SOUTH.
MOSTLY SUNNY SKIES WILL RETURN BY MID DAY SUNDAY. TEMPERATURES
TONIGHT WILL DROP BACK DOWN INTO THE SINGLE DIGITS FOR MOST OF THE
SOUTHEAST PLAINS WHERE THE CORE OF THE COLDER AIR WILL SPREAD IN.
SOME SPOTS COULD DROP INTO THE NEGATIVE DIGITS UP NORTH IF CLEARING
CAN OCCUR EARLY ENOUGH. SAN LUIS VALLEY WILL HAVE THE BENEFIT OF
CLOUDS AND PRECIPITATION OVERNIGHT SO LOWS THERE MAY ONLY DROP INTO
THE TEENS. KEPT HIGH TEMPERATURES ON SUNDAY CLOSER TO THE COLDER
SIDE OF GUIDANCE. -KT
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 330 PM MST SAT NOV 15 2014
...A SLOW WARMING TREND...
A SLOW WARMING TREND TO AROUND MID NOVEMBER AVERAGES REMAINS IN THE
OFFING INTO THE MIDDLE OF THE UPCOMING WORK WEEK...AS COLD NORTH TO
NORTHWEST FLOW ALOFT ACROSS THE REGION SUNDAY NIGHT GIVES WAY TO
WARMER MORE WESTERLY FLOW BY WEDNESDAY. TEMPERATURES TO BE THE MAIN
CONCERN AND HEADACHE IN THE SHORT TERM...WITH HIGHS AND LOWS TO BE
INFLUENCED BY SNOW COVER. AT ANY RATE...HAVE GONE AT OR BELOW THE
COLDER SIDE OF GUIDANCE FOR SUNDAY NIGHT AND MONDAY...ESPECIALLY
ACROSS THE SOUTHEASTERN MTS AND PLAINS WITH LOWS IN THE SINGLE
DIGITS ABOVE AND BELOW ZERO AND HIGHS MAINLY IN THE 20S. INDUCED LEE
TROUGHING AHEAD OF A SHORT WAVE TRANSLATING ACROSS THE NORTHERN
ROCKIES SHOULD KEEP LOWS SLIGHTLY WARMER ACROSS THE EASTERN SLOPES
MONDAY NIGHT AND COULD BOOST HIGHS INTO THE 30S TO LOWER 40S
ACROSS THE LOWER ELEVATIONS ON TUESDAY.
BUILDING UPPER RIDGE ACROSS THE GREAT BASIN TUESDAY NIGHT FLATTENS
ACROSS THE STATE THROUGH WEDNESDAY NIGHT AS MINOR WAVES TRANSLATE
EAST ACROSS THE GREAT BASIN AND ROCKIES...WITH THE DOWNSLOPE FLOW
OWNING TO THE EXPECTED WARMING TEMPERATURES AND BRINGING CHANCES
OF LIGHT SNOWFALL TO THE HIGHER TERRAIN...MAINLY ALONG AND WEST OF
THE CONTDVD THURSDAY AND FRIDAY. LATEST MODELS ARE SHOWING A
STRONGER SYSTEM MOVING ACROSS THE GREAT BASIN FRIDAY AND ACROSS
THE ROCKIES ON SATURDAY...THOUGH BOTH THE GFS AND EC HAVE SHOWN
RUN TO RUN INCONSISTENCIES ON ITS TIMING AND STRENGTH. FOR
NOW...HAVE KEPT ANY PRECIPITATION CHANCES CONFINED TO THE HIGHER
TERRAIN FRIDAY NIGHT AND SATURDAY WITH TEMPERATURES AROUND
SEASONAL AVERAGES.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 330 PM MST SAT NOV 15 2014
EXPECT DETERIORATING CONDITIONS THROUGH THE EVENING WITH
CIGS DROPPING INTO THE IFR CATEGORY AT KCOS AND KPUB BY 00Z AS SNOW
DEVELOPS AND SPREAD OFF THE MOUNTAINS. BOTH TERMINALS COULD SEE
AROUND 2 TO 2.5 INCHES OF SNOW. SNOW SHOULD DIMINISH AFTER 10Z FOR
BOTH TERMINALS WITH CIGS BREAKING BY 15Z. VFR CONDITIONS WILL
CONTINUE THROUGH SUNDAY. KALS WILL SEE A LITTLE LATER START TO THE
SNOW...WITH SNOW SPREADING IN AFTER 05Z...AND CONTINUING THROUGH
12Z. CIGS MAY DROP INTO THE IFR CATEGORY AT TIMES OVERNIGHT.
WIDESPREAD MTN OBSCURATIONS CAN BE EXPECTED TONIGHT WHICH WILL
DECREASE FROM NORTH TO SOUTH SUNDAY MORNING.
MEANWHILE...GUSTY NORTH WINDS WILL CONTINUE THROUGH THE EVENING
ACROSS THE PLAINS BEFORE DIMINISHING OVERNIGHT. KALS WILL SEE GUSTY
WEST WINDS...SHIFTING AROUND TO THE NORTH AFTER 08-09Z AS THE SYSTEM
MOVES ACROSS. WINDS ON SUNDAY WILL BE LIGHTER AT ALL THREE TAF
SITES. -KT
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 9 AM MST SUNDAY FOR COZ072-073-079-
080-087-088-094.
WINTER WEATHER ADVISORY UNTIL 5 AM MST SUNDAY FOR COZ077-078-083-
086.
WINTER STORM WARNING UNTIL 5 AM MST SUNDAY FOR COZ058-060-066.
WINTER STORM WARNING UNTIL 9 AM MST SUNDAY FOR COZ068-074-075.
&&
$$
UPDATE...PETERSEN
SHORT TERM...KT
LONG TERM...MW
AVIATION...KT
AREA FORECAST DISCUSSION
NWS PUEBLO CO
332 PM MST FRI NOV 14 2014
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 232 PM MST FRI NOV 14 2014
...ACTIVE WEATHER CONTINUES...
CURRENT WATER VAPOR IMAGERY AND UPPER AIR ANALYSIS INDICATING
MODERATE TO STRONG WESTERLY FLOW ALOFT ACROSS THE REGION WITH
ANOTHER EMBEBBED SHORT WAVE TRANSLATING ACROSS THE GREAT BASIN AND
INTO WESTERN COLORADO. REGIONAL SATELLITE AND RADAR DATA INDICATING
A GOOD SLUG OF MOISTURE MOVING INTO WESTERN COLORADO ALONG WITH A
FEW LIGHTNING STRIKES ACROSS SOUTHEASTERN UTAH AT THIS TIME.
TEMPERATURES AS OF 2 PM INDICATING SHALLOW COLD AIRMASS PERSISTING
ACROSS SOUTHERN EL PASO COUNTY AND THE LOWER ARKANSAS RIVER VALLEY
FROM CANON CITY TO LAMER...WITH TEMPS IN THE 20S TO LOWER 30S AT
THIS TIME. ELSEWHERE ACROSS THE AREA...TEMPS HAVE WARMED INTO THE
40S TO LOWER 50S WITH MAINLY 20S AND 30S ACROSS THE CONTDVD.
TONIGHT...MODELS CONTINUE TO BRING WAVE ACROSS THE AREA WITH
MODERATE TO HEAVY SNOWFALL EXPECTED ACROSS THE CENTRAL AND SOUTHWEST
MTS AND ACROSS THE HIGHER ELEVATIONS OF THE SANGRE DE CRISTO MTS
THROUGH EARLY SATURDAY MORNING. CURRENT WINTER WEATHER HIGHLIGHTS
LOOK ON TRACK WITH 4 TO 8 INCHES POSSIBLE OVERNIGHT. MODELS...TO A
VARYING DEGREE...CONTINUE TO INDICATE A BAND OF PRECIPITATION...
MOVING INTO THE LA GARITA MTS AT THIS TIME...CONTINUING TO SPREAD
EAST ACROSS THE NORTHERN SAN LUIS VALLEY AND ACROSS THE LOWER
ARKANSAS RIVER THROUGH THE LATE EVENING AND OVERNIGHT HOURS. WHILE
THE 18Z NAM LOOKS HEAVY HANDED IN QPF...RAP AND HRRR HAVE A
SIMILAR SET UP AND HAVE INCREASED POPS ACROSS THIS AREA TO MATCH
KEEPING ACCUMULATIONS OF AN INCH OR LESS AT THIS TIME.
HOWEVER...WILL NEED TO CONTINUE TO MONITOR THE DEVELOPMENT OF THIS
BAND AS THE 18Z NAM IS GIVING UP TO 3 INCHES ACROSS THE LOWER ARK
VALLEY TONIGHT. WITH EXPECTED CLOUD COVER...EXPECTING LOWS TO BE
MAINLY IN THE 20S ACROSS THE AREA.
TOMORROW...MODELS CONTINUE TO DIFFER ON TIMING OF THE NEXT SLUG OF
ARCTIC AIR TO INVADE EASTERN COLORADO...ESPECIALLY ITS ASSOCIATED
PRECIPITATION FIELD. NAM AND EC CONTINUE TO BE SLOWER WITH THE
UPPER TROUGH MOVING ACROSS THE ROCKIES WITH THE GFS REMAINING
FASTER. AT ANY RATE...HAVE PLAYED THE TIMING OF THE ARCTIC FRONT
ACROSS THE PALMER DVD AROUND 18Z...THOUGH HAVE DELAYED ONSET OF
PRECIPITATION INTO THE LATE AFTERNOON. GUSTY NORTH TO NORTHEAST
WINDS OF 20 TO 30 MPH TO ANNOUNCE THE ARRIVAL OF THE FRONT...WHICH
MAY BE ENOUGH TO BRIEFLY MIX OUT THE SHALLOW COLD AIRMASS IN PLACE
ACROSS THE LOWER ARK VALLEY...BEFORE TEMPS COOL AGAIN BEHIND THE
FRONT. NEEDLESS TO SAY...FORECASTING HIGH TEMPERATURES TOMORROW
WILL AGAIN BE A CHALLENGE.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 232 PM MST FRI NOV 14 2014
...SNOW CONTINUES SATURDAY NIGHT THROUGH SUNDAY...
UPPER TROF WILL DROP IN FROM THE NORTHWEST SATURDAY NIGHT BRINGING
A HEALTHY BOUT OF UPPER FORCING ACROSS THE AREA IS IT DROPS TO THE
SOUTHEAST. THERE ARE STILL SOME TIMING DIFFERENCES IN THE MODELS
WITH THE ONSET OF THE PRECIPITATION...ESPECIALLY FOR THE SOUTHEAST
MTS/PLAINS. GFS IS A TOUCH FASTER WITH THE SOUTHWARD PROGRESSION
OF THE UPPER TROF...WHICH MAY BE THE REASON IT IS TRENDING FASTER
WITH THE ONSET OF PRECIPITATION VS THE SLOWER NAM12 AND ECMWF.
FRONT WILL HAVE ALREADY BLASTED THROUGH SOUTHEAST CO BY 00Z
SUN...AND GIVEN ITS ARCTIC ORIGIN...THIS TIMING LOOKS REASONABLE.
HOWEVER...WITH THE UPPER FORCING IS STILL WELL OFF TO THE NORTH
DURING THIS TIME PERIOD...AND A SLOWER TIMING TO THE ONSET OF
PRECIPITATION...ESP FOR THE SE PLAINS...SEEMS MORE REASONABLE.
NORTHEAST UPSLOPE BEHIND THE FRONT IS RATHER SHALLOW (BELOW H7) BUT
AS UPPER TROF DROPS IN FROM THE NORTHWEST...THERE WILL BE A PERIOD
OF UPGLIDE OVER THE COLD DOME DURING THE EVENING AND OVERNIGHT
HOURS. THE GFS SHOWS SOME PRETTY GOOD DIV-Q...THE CORE OF WHICH
PASSES ACROSS UT/THE 4 CORNERS REGION/SRN CO/AND NORTHERN NM. SO
ALTHOUGH UPSLOPE IS SHALLOW FOR THE SOUTHEAST MTS...AND NOT THE
BEST FOR THE SOUTHWEST MOUNTAINS WITH FLOW ALOFT MORE WESTERLY
(INSTEAD OF THE MORE FAVORABLE SOUTHWEST DIRECTION)...HAVE SEEN
THESE DYNAMIC SYSTEMS PRODUCE WIDESPREAD MODERATE TO HEAVY
SNOWFALL AMOUNTS. WITH TIMING OF THE FORCING EXITING SOUTHERN CO
AROUND OR SHORTLY AFTER 12Z SUN...PLAN TO KEEP THE HEADLINE TIMING
FOR THE CONTINENTAL DIVIDE AS IS FOR NOW. HOWEVER...IF MOISTURE
DIMINISHES RAPIDLY ENOUGH BEHIND THE TROF...ITS POSSIBLE THAT THE
SNOW MAY DECREASE A BIT SOONER FARTHER NORTH ACROSS THE SAWATCH
AND MOSQUITO RANGES. GIVEN THE INCONSISTENCIES BETWEEN
MODELS...WILL LET LATER SHIFTS REFINE THE TIMING AS NEED BE.
ADDITIONAL SNOWFALL AMOUNTS IN THE 4 TO 8 INCH RANGE LOOKS
REASONABLE ALONG THE CONTINENTAL DIVIDE SAT NIGHT GIVEN THE
PROBABILITY FOR 20+/1 LIQUID/SNOW RATIOS. STILL SOME UNCERTAINTY
FOR SNOWFALL AMOUNTS ACROSS THE SOUTHEAST MOUNTAINS...AS THE GFS
IS HEAVIER WITH QPF ACROSS THE PIKES PEAK REGION VS THE DRIER
NAM12. HUNCH IS THAT SOUTHEAST MOUNTAINS AND PORTIONS OF THE I-25
CORRIDOR MAY NEED AN ADVISORY SAT NIGHT...WITH THE WETS AND
SANGRES LIKELY TO SEE SOMEWHERE IN THE 3-8 INCH RANGE. TELLER AND
EL PASO COUNTIES STILL VERY MUCH IN THE AIR WITH NAM SUGGESTING
ONLY AN INCH OR TWO SAT NIGHT...WHILE GFS HAS 2 TO NEARLY 4
INCHES. GIVEN THE TRACK OF THE STRONGER FORCING ALOFT...IT DOES
MAKE SENSE THAT THE LIGHTER NAM12 AMOUNTS COULD BE MORE
REASONABLE. SUSPECT THAT SOME BANDING OF SNOW ALONG/SOUTH OF THE
ARKANSAS RIVER WILL EXTEND EASTWARD ACROSS THE SOUTHEAST
PLAINS...BUT SNOWFALL AMOUNTS AT THIS TIME APPEAR TO STAY BELOW
ADVISORY LEVELS...PERHAPS 1-3" RANGE. AGAIN GIVEN THE COLD AIRMASS
WITH THIS EVENT...IT SHOULD BE ANOTHER DRY FLUFFY SNOW EVENT. THE
DIFFERENCE THIS TIME WILL BE THAT THE ROAD SURFACES WILL START OUT
COLDER GIVEN OUR PREVIOUS COLD OUTBREAK. THIS COULD LIMIT THE
ICING FACTOR SOME DEPENDING ON ASPHALT TEMPERATURES SATURDAY
AFTERNOON.
SNOW WILL END FROM NORTH TO SOUTH DURING THE MORNING ON
SUNDAY...AND SNOW COVER WILL LIKELY KEEP TEMPERATURES FROM WARMING
MUCH. HAVE DROPPED HIGHS A FEW DEGREES FROM THE CONSENSUS
GRIDS...WHICH PUTS THEM CLOSER TO THE COLDER SIDE OF GUIDANCE
VALUES.
FORECAST DRIES OUT FOR THE REMAINDER OF THE EXTENDED. ANOTHER
SURFACE HIGH DESCENDS THROUGH THE PLAINS WITH SOME UNCERTAINTIES
AS TO HOW FAR WEST THE CORE OF COLD AIR ASSOCIATED WITH IT WILL
GET. NAM12 AND EC ARE SEVERAL DEGREES COOLER WITH H7 TEMPS ACROSS
THE PLAINS VS THE WARMER GFS MONDAY AFTERNOON...WHICH PUTS HIGH
TEMPERATURES IN QUESTION ACROSS THE PLAINS. CURRENT GRIDS ARE
CARRYING MID 20S TO AROUND 30...BUT THESE MAY NEED TO BE COOLED
OFF EVEN FURTHER DEPENDING ON HOW THIS EVOLVES.
NORTHERLY FLOW ALOFT GRADUALLY SHIFTS TO A MORE WESTERLY DIRECTION WHICH
SHOULD BRING SOME MODERATING TEMPERATURES THROUGH MID TO LATE
WEEK. ANOTHER PACIFIC SYSTEM MAY CUT THROUGH THE WESTERN U.S.
UPPER RIDGE TOWARDS FRIDAY. FORECAST WILL CARRY GENERALLY DRY
CONDITIONS UNTIL FRIDAY WITH TEMPERATURES WARMING BUT STILL
REMAINING BELOW NORMAL. -KT
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 232 PM MST FRI NOV 14 2014
MAINLY VFR CONDITIONS EXPECTED AT TAF SITES THROUGH THE DAY
TOMORROW. WILL SEE INCREASING SHOWERS ACROSS THE HIGHER TERRAIN
THROUGH THE EVENING WITH A FEW OF THE MODELS INDICATING A BAND OF
PRECIPITATION SPREADING OFF THE HIGHER TERRAIN AND OUT ACROSS THE
LOWER ARKANSAS RIVER THIS EVENING. STILL NOT SURE ON THE EXACT
LOCATION OF THIS DEVELOPMENT...THOUGH WILL GO WITH A PERIOD OF MFVR
AND SNOW SHOWERS FOR PUB FROM 02Z THROUGH 06Z...WHILE KEEPING
VCSH AT COS AND ALS.
THE NEXT ARCTIC FRONT IS POSED TO MOVE ACROSS THE EASTERN PLAINS
LATE MORNING AND AFTERNOON...WITH GUSTY NORTH TO NORTHEAST WINDS OF
20 TO 30 MPH AND LOWERING CIGS EXPECTED AT COS AND PUB AFT 18Z SAT.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING UNTIL 5 AM MST SUNDAY FOR COZ058-060-066-
068.
WINTER WEATHER ADVISORY UNTIL 5 AM MST SATURDAY FOR COZ073-075.
&&
$$
SHORT TERM...MW
LONG TERM...KT
AVIATION...MW
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1239 PM MST FRI NOV 14 2014
.UPDATE...
ISSUED AT 1239 PM MST FRI NOV 14 2014
UPDATED FOR CURRENT OBSERVATIONAL DATA AND FORECAST TRENDS...WHICH
HAS SHALLOW COLD AIRMASS HANGING ACROSS SOUTHERN PORTIONS OF EL
PASO COUNTY AND ESPECIALLY THE LOWER ARKANSAS RIVER VALLEY
THROUGH THE AFTERNOON.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 400 AM MST FRI NOV 14 2014
...MAX TEMPS TODAY ON THE PLAINS WILL SHOW LOTS OF VARIABILITY...
...SAN JUANS TO GET POUNDED THIS EVENING...
CURRENTLY...
AT 2 AM...TEMPS THIS MORNING SHOWING QUITE A BIT OF VARIABILITY
ACROSS THE REGION. THE ARCTIC AIR HAS ALREADY BEGUN TO RETREAT AS
ELEVATIONS GENERALLY ABOVE 6500 FEET ARE IN THE (RELATIVELY) WARMER
AIR. AS AN EXAMPLE...AREAS OF N EL PASO COUNTY ARE IN THE TEENS AND
20S WHILE KCOS WAS 3F. AREAS JUST WEST OF WALSENBURG AND WEST OF
KTAD WERE IN THE 20S AND 30S WHILE COLORADO CITY AND TRINIDAD WERE 2
AND 7F RESPECTIVELY.
IN THE MTNS AND VALLEYS IT WAS RELATIVELY WARM WITH 2 AM TEMPS IN
THE 20S TO LOWER 30S. SNOW WAS FALLING ACROSS THE CONTDVD AND
ACROSS THE SANGRE DE CRISTO MTNS.
TODAY...
I AM QUITE CONFIDENT WE ARE GOING TO SEE QUITE A BIT OF VARIABILITY
IN MAX TEMPS TODAY OVER THE PLAINS...I AM JUST UNCERTAIN ON THE
MAGNITUDE OF THE VARIABILITY. HRRR GUIDANCE SHOWS AREAS OF THE LWR
ARK RVR VLY FROM KPUB EASTWARD TO KLAA NOT GETTING OUT OF THE TEENS
WHILE AREAS N AND S OF THE RIVER WILL GET INTO THE 30S AND 40S. FOR
NOW I AM NOT GOING TO GO THAT EXTREME...ALTHOUGH I PLAN TO KEEP
AREAS OF THE LOWER ARK RVR VALLEY MUCH COOLER THAN THE
SURROUNDING PLAINS. FOR NOW PLAN TO HAVE AREAS SUCH AS KPUB...KLHX
AND KLAA IN THE UPPER 20S TO LOWER 30S WHILE KCOS WILL BE IN THE
UPPER 30S...AIR FORCE AROUND 40...CANON CITY...COLORADO
CITY...WALSENBURG AND TRINIDAD WILL BE IN THE MID 40S. I WOULD
NOT BE TOO SURPRISED IF PUEBLO WEST WAS IN THE MID 40S WHILE KPUB
WILL BE IN THE LOWER 30S. THE WARMEST AREA ACROSS THE REGION
TODAY WILL LIKELY BE THE SAN LUIS VALLEY WHERE KALS WILL LIKELY BE
IN THE LOWER 50S.
AS FOR THE MTNS...ALTHOUGH A WINTER STORM WARNING IS IN EFFECT ALL
DAY FOR THE CONTDVD REGION...I EXPECT SNOW TO DECREASE SIGNIFICANTLY
LATER THIS MORNING ACROSS THE DIVIDE (SOME AREAS MAY SEE THE SNOW
STOP COMPLETELY). THE SNOW WILL LIKELY NOT START TO RAMP UP AGAIN
UNTIL MID TO LATER AFTERNOON ACROSS THE DIVIDE. HOWEVER...ONCE IT
RAMPS UP AGAIN...IT WILL REALLY RAMP UP...ESPECIALLY ACROSS THE SAN
JUANS (SEE TONIGHT).
TONIGHT...
THE SAN JUANS ARE LIKELY GOING TO GET POUNDED ESPECIALLY THIS
EVENING. SNOWFALL RATES WILL LIKELY EXCEED 2" PER HOUR FOR AT LEAST
A FEW HOURS THIS EVENING AS THE BEST FORCING MOVES ACROSS. ALL
GUIDANCE INDICATES THIS. A FEW LTG FLASHES ARE LIKELY THIS EVENING
AS THIS FORCING MOVES ACROSS (SEE SPC DAY1 GUIDANCE). THE C MTNS
WILL ALSO SEE PERIODS OF HEAVY SNOW TONIGHT. IN ADDITION...HAVE
ADDED HILITES FOR THE SANGRES AS THEY WILL LIKELY SEE 4-8" TONITE.
THE BEST CHANCE FOR THE SAN LUIS VALLEY TO SEE PRECIP WILL BE THIS
EVENING. LOCALLY 1-2" ACCUMS WILL BE POSSIBLE...ESPECIALLY AREAS
CLOSER TO THE MOUNTAINS.
THE PLAINS WILL LIKELY SEE SOME PRECIP TONIGHT. OVERALL...GUIDANCE
HAS BACKED OFF SOME AND I HAVE REDUCED POPS OVER THE PLAINS. THE
BEST CHANCE OF ANY ACCUM PRECIP STILL APPEARS TO BE OVER THE FAR
EASTERN PLAINS...ALTHOUGH IF A SNOW BAND DEVELOPS...(AS SOME
GUIDANCE IS HINTING AT)...LOCALLY 1-2" ACCUMS WILL BE POSSIBLE. THE
PLAINS WILL HAVE TO BE WATCHED CAREFULLY LATE TODAY TO SEE IF ANY
BANDED PRECIP DEVELOPS. /HODANISH
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 400 AM MST FRI NOV 14 2014
...A COUPLE MORE SYSTEMS TO IMPACT THE AREA THROUGH THE
WEEKEND...
THE WINTER STORM WARNING WILL REMAIN IN EFFECT FOR THE SAN JUAN AND
LA GARITA MOUNTAINS...CONTINENTAL DIVIDE...THROUGH 5 AM SUNDAY.
HOWEVER...SOME CONCERN THAT THERE WILL BE A DEFINITE LULL IN THE
SNOWFALL SATURDAY AFTERNOON AS THE PACIFIC SHORTWAVE MOVES OUT OF
COLORADO. NEXT TROF DROPPING SOUTH OF CANADA WILL IMPACT THE AREA
SATURDAY AFTERNOON AND SATURDAY NIGHT. THIS TROF WILL HAVE A WIDER
IMPACT ON THE FORECAST AREA AS TEMPERATURES COOL DURING THE DAY
SATURDAY WITH FRONT MOVING THROUGH THE PLAINS AND A BAND OF SNOW
SETTING UP ALONG THE I-25 CORRIDOR AND THE SOUTHEAST PLAINS SATURDAY
NIGHT. GFS HAS MOST OF THE PRECIPITATION/SNOWFALL ALONG THE EAST
SLOPES OF THE RAMPARTS AND SANGRES. HUERFANO AND LAS ANIMAS COUNTIES
MAY SEE THE BULK OF THE SNOWFALL WITH THIS SYSTEM OVERNIGHT SATURDAY
WITH A BAND OF SNOW STRETCHING INTO BACA COUNTY. LATER SHIFTS MAY
HAVE TO BALANCE THE WINTER STORM HIGHLIGHTS...MAYBE DOWNGRADING THE
WINTER STORM WARNING FOR THE CONTINENTAL DIVIDE AS THE SNOWFALL
DIMINISHES...AND AN EYE TOWARD A HIGHLIGHT FOR THE SOUTHERN I-25
CORRIDOR AND SOUTHERN PLAINS. ECMWF AND NAM NOT AS BULLISH ON THE
QPF FOR THE SAME AREAS...SO SOME UNCERTAINTY REMAINS. HAVE TRIED
TO TIME THE FRONTAL PASSAGE ON THE PLAINS AND FALLING TEMPERATURES
DURING THE DAY SATURDAY.
TROF CONTINUES TO MOVE SOUTH SUNDAY WITH NORTHWESTERLY FLOW ALOFT
EXPECTED TO BRING ANOTHER FRONTAL BOUNDARY THROUGH THE EASTERN
PLAINS MONDAY NIGHT...THOUGH TEMPERATURES WILL NOT FALL AS MUCH
BEHIND THIS FRONT. SNOW SHOWERS ARE POSSIBLE IN THE CENTRAL
MOUNTAINS WITH THIS NORTHWEST FLOW. GENERALLY DRY AND WARMER
CONDITIONS ARE EXPECTED TUESDAY THROUGH AT LEAST THURSDAY WITH
WESTERLY FLOW ALOFT AND WEAK LEE TROF DEVELOPING AT THE SURFACE.
WEATHER PATTERN REMAINS ACTIVE TO OUR NORTH AND WEST AND EXTENDED
MODELS DO SHOW ENERGY MOVING INTO THE NORTH CENTRAL MOUNTAINS
THURSDAY. STARK
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1055 AM MST FRI NOV 14 2014
MAINLY VFR CONDITIONS EXPECTED AT COS...PUB AND ALS OVER THE NEXT
24 HOURS. WILL SEE INCREASING SHOWERS ACROSS THE HIGHER TERRAIN
THROUGH THE AFTERNOON WITH A FEW OF THE MODELS INDICATING A BAND
OF PRECIPITATION SPREADING OFF THE HIGHER TERRAIN AND OUT ACROSS
THE LOWER ARKANSAS RIVER THIS EVENING. NOT SURE OF THE LOCATION OF
THE SAID BAND OF SHOWERS...AND HAVE KEPT VCSH IN TAFS THROUGH 06Z
SAT ATTM. IF THIS BAND DOES SET UP...COULD SEE MVFR AND LOCAL IFR
CONDITIONS WITH UP TO AN INCH OF SNOW ACCUMS...ESPECIALLY AT ALS
AND PUB.
THE NEXT ARCTIC FRONT IS POSED TO MOVE ACROSS THE EASTERN PLAINS
LATE MORNING AND AFTERNOON...JUST OUT OF THIS TAF PERIOD...WITH
GUSTY NORTH TO NORTHEAST WINDS AND LOWERING CIGS EXPECTED AT COS
AND PUB AFT 18Z SAT.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING UNTIL 5 AM MST SUNDAY FOR COZ058-060-066-
068.
WINTER WEATHER ADVISORY UNTIL 5 AM MST SATURDAY FOR COZ073-075.
&&
$$
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1054 AM MST FRI NOV 14 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 400 AM MST FRI NOV 14 2014
...MAX TEMPS TODAY ON THE PLAINS WILL SHOW LOTS OF VARIABILITY...
...SAN JUANS TO GET POUNDED THIS EVENING...
CURRENTLY...
AT 2 AM...TEMPS THIS MORNING SHOWING QUITE A BIT OF VARIABILITY
ACROSS THE REGION. THE ARCTIC AIR HAS ALREADY BEGUN TO RETREAT AS
ELEVATIONS GENERALLY ABOVE 6500 FEET ARE IN THE (RELATIVELY) WARMER
AIR. AS AN EXAMPLE...AREAS OF N EL PASO COUNTY ARE IN THE TEENS AND
20S WHILE KCOS WAS 3F. AREAS JUST WEST OF WALSENBURG AND WEST OF
KTAD WERE IN THE 20S AND 30S WHILE COLORADO CITY AND TRINIDAD WERE 2
AND 7F RESPECTIVELY.
IN THE MTNS AND VALLEYS IT WAS RELATIVELY WARM WITH 2 AM TEMPS IN
THE 20S TO LOWER 30S. SNOW WAS FALLING ACROSS THE CONTDVD AND
ACROSS THE SANGRE DE CRISTO MTNS.
TODAY...
I AM QUITE CONFIDENT WE ARE GOING TO SEE QUITE A BIT OF VARIABILITY
IN MAX TEMPS TODAY OVER THE PLAINS...I AM JUST UNCERTAIN ON THE
MAGNITUDE OF THE VARIABILITY. HRRR GUIDANCE SHOWS AREAS OF THE LWR
ARK RVR VLY FROM KPUB EASTWARD TO KLAA NOT GETTING OUT OF THE TEENS
WHILE AREAS N AND S OF THE RIVER WILL GET INTO THE 30S AND 40S. FOR
NOW I AM NOT GOING TO GO THAT EXTREME...ALTHOUGH I PLAN TO KEEP
AREAS OF THE LOWER ARK RVR VALLEY MUCH COOLER THAN THE
SURROUNDING PLAINS. FOR NOW PLAN TO HAVE AREAS SUCH AS KPUB...KLHX
AND KLAA IN THE UPPER 20S TO LOWER 30S WHILE KCOS WILL BE IN THE
UPPER 30S...AIR FORCE AROUND 40...CANON CITY...COLORADO
CITY...WALSENBURG AND TRINIDAD WILL BE IN THE MID 40S. I WOULD
NOT BE TOO SURPRISED IF PUEBLO WEST WAS IN THE MID 40S WHILE KPUB
WILL BE IN THE LOWER 30S. THE WARMEST AREA ACROSS THE REGION
TODAY WILL LIKELY BE THE SAN LUIS VALLEY WHERE KALS WILL LIKELY BE
IN THE LOWER 50S.
AS FOR THE MTNS...ALTHOUGH A WINTER STORM WARNING IS IN EFFECT ALL
DAY FOR THE CONTDVD REGION...I EXPECT SNOW TO DECREASE SIGNIFICANTLY
LATER THIS MORNING ACROSS THE DIVIDE (SOME AREAS MAY SEE THE SNOW
STOP COMPLETELY). THE SNOW WILL LIKELY NOT START TO RAMP UP AGAIN
UNTIL MID TO LATER AFTERNOON ACROSS THE DIVIDE. HOWEVER...ONCE IT
RAMPS UP AGAIN...IT WILL REALLY RAMP UP...ESPECIALLY ACROSS THE SAN
JUANS (SEE TONIGHT).
TONIGHT...
THE SAN JUANS ARE LIKELY GOING TO GET POUNDED ESPECIALLY THIS
EVENING. SNOWFALL RATES WILL LIKELY EXCEED 2" PER HOUR FOR AT LEAST
A FEW HOURS THIS EVENING AS THE BEST FORCING MOVES ACROSS. ALL
GUIDANCE INDICATES THIS. A FEW LTG FLASHES ARE LIKELY THIS EVENING
AS THIS FORCING MOVES ACROSS (SEE SPC DAY1 GUIDANCE). THE C MTNS
WILL ALSO SEE PERIODS OF HEAVY SNOW TONIGHT. IN ADDITION...HAVE
ADDED HILITES FOR THE SANGRES AS THEY WILL LIKELY SEE 4-8" TONITE.
THE BEST CHANCE FOR THE SAN LUIS VALLEY TO SEE PRECIP WILL BE THIS
EVENING. LOCALLY 1-2" ACCUMS WILL BE POSSIBLE...ESPECIALLY AREAS
CLOSER TO THE MOUNTAINS.
THE PLAINS WILL LIKELY SEE SOME PRECIP TONIGHT. OVERALL...GUIDANCE
HAS BACKED OFF SOME AND I HAVE REDUCED POPS OVER THE PLAINS. THE
BEST CHANCE OF ANY ACCUM PRECIP STILL APPEARS TO BE OVER THE FAR
EASTERN PLAINS...ALTHOUGH IF A SNOW BAND DEVELOPS...(AS SOME
GUIDANCE IS HINTING AT)...LOCALLY 1-2" ACCUMS WILL BE POSSIBLE. THE
PLAINS WILL HAVE TO BE WATCHED CAREFULLY LATE TODAY TO SEE IF ANY
BANDED PRECIP DEVELOPS. /HODANISH
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 400 AM MST FRI NOV 14 2014
...A COUPLE MORE SYSTEMS TO IMPACT THE AREA THROUGH THE
WEEKEND...
THE WINTER STORM WARNING WILL REMAIN IN EFFECT FOR THE SAN JUAN AND
LA GARITA MOUNTAINS...CONTINENTAL DIVIDE...THROUGH 5 AM SUNDAY.
HOWEVER...SOME CONCERN THAT THERE WILL BE A DEFINITE LULL IN THE
SNOWFALL SATURDAY AFTERNOON AS THE PACIFIC SHORTWAVE MOVES OUT OF
COLORADO. NEXT TROF DROPPING SOUTH OF CANADA WILL IMPACT THE AREA
SATURDAY AFTERNOON AND SATURDAY NIGHT. THIS TROF WILL HAVE A WIDER
IMPACT ON THE FORECAST AREA AS TEMPERATURES COOL DURING THE DAY
SATURDAY WITH FRONT MOVING THROUGH THE PLAINS AND A BAND OF SNOW
SETTING UP ALONG THE I-25 CORRIDOR AND THE SOUTHEAST PLAINS SATURDAY
NIGHT. GFS HAS MOST OF THE PRECIPITATION/SNOWFALL ALONG THE EAST
SLOPES OF THE RAMPARTS AND SANGRES. HUERFANO AND LAS ANIMAS COUNTIES
MAY SEE THE BULK OF THE SNOWFALL WITH THIS SYSTEM OVERNIGHT SATURDAY
WITH A BAND OF SNOW STRETCHING INTO BACA COUNTY. LATER SHIFTS MAY
HAVE TO BALANCE THE WINTER STORM HIGHLIGHTS...MAYBE DOWNGRADING THE
WINTER STORM WARNING FOR THE CONTINENTAL DIVIDE AS THE SNOWFALL
DIMINISHES...AND AN EYE TOWARD A HIGHLIGHT FOR THE SOUTHERN I-25
CORRIDOR AND SOUTHERN PLAINS. ECMWF AND NAM NOT AS BULLISH ON THE
QPF FOR THE SAME AREAS...SO SOME UNCERTAINTY REMAINS. HAVE TRIED
TO TIME THE FRONTAL PASSAGE ON THE PLAINS AND FALLING TEMPERATURES
DURING THE DAY SATURDAY.
TROF CONTINUES TO MOVE SOUTH SUNDAY WITH NORTHWESTERLY FLOW ALOFT
EXPECTED TO BRING ANOTHER FRONTAL BOUNDARY THROUGH THE EASTERN
PLAINS MONDAY NIGHT...THOUGH TEMPERATURES WILL NOT FALL AS MUCH
BEHIND THIS FRONT. SNOW SHOWERS ARE POSSIBLE IN THE CENTRAL
MOUNTAINS WITH THIS NORTHWEST FLOW. GENERALLY DRY AND WARMER
CONDITIONS ARE EXPECTED TUESDAY THROUGH AT LEAST THURSDAY WITH
WESTERLY FLOW ALOFT AND WEAK LEE TROF DEVELOPING AT THE SURFACE.
WEATHER PATTERN REMAINS ACTIVE TO OUR NORTH AND WEST AND EXTENDED
MODELS DO SHOW ENERGY MOVING INTO THE NORTH CENTRAL MOUNTAINS
THURSDAY. STARK
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1055 AM MST FRI NOV 14 2014
MAINLY VFR CONDITIONS EXPECTED AT COS...PUB AND ALS OVER THE NEXT
24 HOURS. WILL SEE INCREASING SHOWERS ACROSS THE HIGHER TERRAIN
THROUGH THE AFTERNOON WITH A FEW OF THE MODELS INDICATING A BAND
OF PRECIPITATION SPREADING OFF THE HIGHER TERRAIN AND OUT ACROSS
THE LOWER ARKANSAS RIVER THIS EVENING. NOT SURE OF THE LOCATION OF
THE SAID BAND OF SHOWERS...AND HAVE KEPT VCSH IN TAFS THROUGH 06Z
SAT ATTM. IF THIS BAND DOES SET UP...COULD SEE MVFR AND LOCAL IFR
CONDITIONS WITH UP TO AN INCH OF SNOW ACCUMS...ESPECIALLY AT ALS
AND PUB.
THE NEXT ARCTIC FRONT IS POSED TO MOVE ACROSS THE EASTERN PLAINS
LATE MORNING AND AFTERNOON...JUST OUT OF THIS TAF PERIOD...WITH
GUSTY NORTH TO NORTHEAST WINDS AND LOWERING CIGS EXPECTED AT COS
AND PUB AFT 18Z SAT.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING UNTIL 5 AM MST SUNDAY FOR COZ058-060-066-
068.
WINTER WEATHER ADVISORY UNTIL 5 AM MST SATURDAY FOR COZ073-075.
&&
$$
SHORT TERM...HODANISH
LONG TERM...STARK
AVIATION...MW
AREA FORECAST DISCUSSION
NWS PUEBLO CO
409 AM MST FRI NOV 14 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 400 AM MST FRI NOV 14 2014
...MAX TEMPS TODAY ON THE PLAINS WILL SHOW LOTS OF VARIABILITY...
...SAN JUANS TO GET POUNDED THIS EVENING...
CURRENTLY...
AT 2 AM...TEMPS THIS MORNING SHOWING QUITE A BIT OF VARIABILITY
ACROSS THE REGION. THE ARCTIC AIR HAS ALREADY BEGUN TO RETREAT AS
ELEVATIONS GENERALLY ABOVE 6500 FEET ARE IN THE (RELATIVELY) WARMER
AIR. AS AN EXAMPLE...AREAS OF N EL PASO COUNTY ARE IN THE TEENS AND
20S WHILE KCOS WAS 3F. AREAS JUST WEST OF WALSENBURG AND WEST OF
KTAD WERE IN THE 20S AND 30S WHILE COLORADO CITY AND TRINIDAD WERE 2
AND 7F RESPECTIVELY.
IN THE MTNS AND VALLEYS IT WAS RELATIVELY WARM WITH 2 AM TEMPS IN
THE 20S TO LOWER 30S. SNOW WAS FALLING ACROSS THE CONTDVD AND
ACROSS THE SANGRE DE CRISTO MTNS.
TODAY...
I AM QUITE CONFIDENT WE ARE GOING TO SEE QUITE A BIT OF VARIABILITY
IN MAX TEMPS TODAY OVER THE PLAINS...I AM JUST UNCERTAIN ON THE
MAGNITUDE OF THE VARIABILITY. HRRR GUIDANCE SHOWS AREAS OF THE LWR
ARK RVR VLY FROM KPUB EASTWARD TO KLAA NOT GETTING OUT OF THE TEENS
WHILE AREAS N AND S OF THE RIVER WILL GET INTO THE 30S AND 40S. FOR
NOW I AM NOT GOING TO GO THAT EXTREME...ALTHOUGH I PLAN TO KEEP
AREAS OF THE LOWER ARK RVR VALLEY MUCH COOLER THAN THE
SURROUNDING PLAINS. FOR NOW PLAN TO HAVE AREAS SUCH AS KPUB...KLHX
AND KLAA IN THE UPPER 20S TO LOWER 30S WHILE KCOS WILL BE IN THE
UPPER 30S...AIR FORCE AROUND 40...CANON CITY...COLORADO
CITY...WALSENBURG AND TRINIDAD WILL BE IN THE MID 40S. I WOULD
NOT BE TOO SURPRISED IF PUEBLO WEST WAS IN THE MID 40S WHILE KPUB
WILL BE IN THE LOWER 30S. THE WARMEST AREA ACROSS THE REGION
TODAY WILL LIKELY BE THE SAN LUIS VALLEY WHERE KALS WILL LIKELY BE
IN THE LOWER 50S.
AS FOR THE MTNS...ALTHOUGH A WINTER STORM WARNING IS IN EFFECT ALL
DAY FOR THE CONTDVD REGION...I EXPECT SNOW TO DECREASE SIGNIFICANTLY
LATER THIS MORNING ACROSS THE DIVIDE (SOME AREAS MAY SEE THE SNOW
STOP COMPLETELY). THE SNOW WILL LIKELY NOT START TO RAMP UP AGAIN
UNTIL MID TO LATER AFTERNOON ACROSS THE DIVIDE. HOWEVER...ONCE IT
RAMPS UP AGAIN...IT WILL REALLY RAMP UP...ESPECIALLY ACROSS THE SAN
JUANS (SEE TONIGHT).
TONIGHT...
THE SAN JUANS ARE LIKELY GOING TO GET POUNDED ESPECIALLY THIS
EVENING. SNOWFALL RATES WILL LIKELY EXCEED 2" PER HOUR FOR AT LEAST
A FEW HOURS THIS EVENING AS THE BEST FORCING MOVES ACROSS. ALL
GUIDANCE INDICATES THIS. A FEW LTG FLASHES ARE LIKELY THIS EVENING
AS THIS FORCING MOVES ACROSS (SEE SPC DAY1 GUIDANCE). THE C MTNS
WILL ALSO SEE PERIODS OF HEAVY SNOW TONIGHT. IN ADDITION...HAVE
ADDED HILITES FOR THE SANGRES AS THEY WILL LIKELY SEE 4-8" TONITE.
THE BEST CHANCE FOR THE SAN LUIS VALLEY TO SEE PRECIP WILL BE THIS
EVENING. LOCALLY 1-2" ACCUMS WILL BE POSSIBLE...ESPECIALLY AREAS
CLOSER TO THE MOUNTAINS.
THE PLAINS WILL LIKELY SEE SOME PRECIP TONIGHT. OVERALL...GUIDANCE
HAS BACKED OFF SOME AND I HAVE REDUCED POPS OVER THE PLAINS. THE
BEST CHANCE OF ANY ACCUM PRECIP STILL APPEARS TO BE OVER THE FAR
EASTERN PLAINS...ALTHOUGH IF A SNOW BAND DEVELOPS...(AS SOME
GUIDANCE IS HINTING AT)...LOCALLY 1-2" ACCUMS WILL BE POSSIBLE. THE
PLAINS WILL HAVE TO BE WATCHED CAREFULLY LATE TODAY TO SEE IF ANY
BANDED PRECIP DEVELOPS. /HODANISH
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 400 AM MST FRI NOV 14 2014
...A COUPLE MORE SYSTEMS TO IMPACT THE AREA THROUGH THE
WEEKEND...
THE WINTER STORM WARNING WILL REMAIN IN EFFECT FOR THE SAN JUAN AND
LA GARITA MOUNTAINS...CONTINENTAL DIVIDE...THROUGH 5 AM SUNDAY.
HOWEVER...SOME CONCERN THAT THERE WILL BE A DEFINITE LULL IN THE
SNOWFALL SATURDAY AFTERNOON AS THE PACIFIC SHORTWAVE MOVES OUT OF
COLORADO. NEXT TROF DROPPING SOUTH OF CANADA WILL IMPACT THE AREA
SATURDAY AFTERNOON AND SATURDAY NIGHT. THIS TROF WILL HAVE A WIDER
IMPACT ON THE FORECAST AREA AS TEMPERATURES COOL DURING THE DAY
SATURDAY WITH FRONT MOVING THROUGH THE PLAINS AND A BAND OF SNOW
SETTING UP ALONG THE I-25 CORRIDOR AND THE SOUTHEAST PLAINS SATURDAY
NIGHT. GFS HAS MOST OF THE PRECIPITATION/SNOWFALL ALONG THE EAST
SLOPES OF THE RAMPARTS AND SANGRES. HUERFANO AND LAS ANIMAS COUNTIES
MAY SEE THE BULK OF THE SNOWFALL WITH THIS SYSTEM OVERNIGHT SATURDAY
WITH A BAND OF SNOW STRETCHING INTO BACA COUNTY. LATER SHIFTS MAY
HAVE TO BALANCE THE WINTER STORM HIGHLIGHTS...MAYBE DOWNGRADING THE
WINTER STORM WARNING FOR THE CONTINENTAL DIVIDE AS THE SNOWFALL
DIMINISHES...AND AN EYE TOWARD A HIGHLIGHT FOR THE SOUTHERN I-25
CORRIDOR AND SOUTHERN PLAINS. ECMWF AND NAM NOT AS BULLISH ON THE
QPF FOR THE SAME AREAS...SO SOME UNCERTAINTY REMAINS. HAVE TRIED
TO TIME THE FRONTAL PASSAGE ON THE PLAINS AND FALLING TEMPERATURES
DURING THE DAY SATURDAY.
TROF CONTINUES TO MOVE SOUTH SUNDAY WITH NORTHWESTERLY FLOW ALOFT
EXPECTED TO BRING ANOTHER FRONTAL BOUNDARY THROUGH THE EASTERN
PLAINS MONDAY NIGHT...THOUGH TEMPERATURES WILL NOT FALL AS MUCH
BEHIND THIS FRONT. SNOW SHOWERS ARE POSSIBLE IN THE CENTRAL
MOUNTAINS WITH THIS NORTHWEST FLOW. GENERALLY DRY AND WARMER
CONDITIONS ARE EXPECTED TUESDAY THROUGH AT LEAST THURSDAY WITH
WESTERLY FLOW ALOFT AND WEAK LEE TROF DEVELOPING AT THE SURFACE.
WEATHER PATTERN REMAINS ACTIVE TO OUR NORTH AND WEST AND EXTENDED
MODELS DO SHOW ENERGY MOVING INTO THE NORTH CENTRAL MOUNTAINS
THURSDAY. STARK
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 400 AM MST FRI NOV 14 2014
KCOS AND KPUB...EXPECT VFR CONDITIONS THROUGH THE NEXT 24 HOURS.
WE MAY SEE SOME SNOW SHOWERS DEVELOP THIS EVENING ALTHOUGH THE
PRECIP...IF IT DEVELOPS...SHOULD NOT LAST. AT THIS TIME I PLAN TO
MENTION ONLY VCSH IN THE TAF PRODUCTS. WINDS WILL BE LIGHT.
KALS...PRETTY POTENT DISTURBANCE WILL MOVE ACROSS THE MTNS TONIGHT
AND EXPECT THE VALLEY WILL SEE SOME SNOW. THE BEST CHANCE OF IFR
CONDITIONS DUE TO CIGS/PRECIP WILL BE BETWEEN 03Z AND 09Z TONIGHT AT
KALS. OTHERWISE...VFR AND LIGHT WINDS.
SNOW/LIFR CONDITIONS WILL OCCUR ACROSS THE MTNS EARLY THIS MORNING.
PRECIP WILL DECREASE LATER THIS MORNING AND EARLY AFTERNOON...BUT
WILL RETURN BY LATE AFTERNOON. INTENSE SNOWFALL IS EXPECTED OVER THE
CONTDVD AND THE SANGRE DE CRISTO MTNS TONIGHT.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING UNTIL 5 AM MST SUNDAY FOR COZ058-060-066-
068.
WINTER WEATHER ADVISORY FROM 11 AM THIS MORNING TO 5 AM MST
SATURDAY FOR COZ073-075.
WINTER WEATHER ADVISORY UNTIL 5 AM MST EARLY THIS MORNING FOR
COZ059-061.
&&
$$
SHORT TERM...HODANISH
LONG TERM...STARK
AVIATION...HODANISH
AREA FORECAST DISCUSSION
NWS ALBANY NY
1243 AM EST FRI NOV 14 2014
.SYNOPSIS...
FIRST MEASURABLE SNOWFALL FOR MUCH OF THE FORECAST AREA EXPECTED
TONIGHT WITH ACCUMULATIONS MAINLY ON GRASSY SURFACES. SNOW IS
EXPECTED TO COME TO AN END BEFORE THE MORNING COMMUTE. IN THE
MEANTIME...LAKE ENHANCED SNOW WILL CONTINUE INTO THE WESTERN
ADIRONDACKS. A REINFORCING SHOT OF COLD AIR WILL TAKE HOLD FRIDAY
AND LAST INTO THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1215 AM...A BAND OF STEADY LIGHT SNOW IS PROGRESSING
EASTWARD ACROSS THE GREATER CAPITAL DISTRICT AND POINTS SOUTH AND
EAST. LATEST LOCAL HRRR MODEL AND HIRESWRF MODEL RUN UPDATES HAVE
BEEN CONSISTENT WITH SLIGHTLY MORE QPF ACROSS THE SOUTHERN REGIONS
WHERE SNOWFALL TOTALS HAVE BEEN INCREASED SLIGHTLY IN THE HIGHEST
TERRAIN ACROSS THE SOUTHERN BERKSHIRES INTO THE NORTHERN
LITCHFIELD HILLS WILL RANGE BETWEEN ONE TO TWO INCHES WITH
ISOLATED AREAS UP TO THREE INCHES POSSIBLE BY EARLY FRIDAY
MORNING.
THE PRECIPITATION MAINLY IN THE FORM OF SNOW IS EXPECTED TO END
BEFORE THE MORNING COMMUTE...BY AROUND 07Z ACROSS OUR WESTERN NEW
ENGLAND COUNTIES. GENERALLY LOOKING AT LESS THAN AN INCH BELOW
1000 FEET WITH 1 TO 2 INCHES ABOVE 1000 FEET AND FOR LITCHFIELD
COUNTY.
LAKE ENHANCED SNOW WILL CONTINUE INTO THE WESTERN ADIRONDACKS
TONIGHT AS THE SOUTHWESTERLY FLOW CONTINUES AHEAD OF APPROACHING
TROUGH. AMOUNTS ARE GENERALLY EXPECTED TO BE LIGHT ACROSS THIS
AREA MAINLY UNDER 2 INCHES.
TEMPERATURES ARE EXPECTED TO DROPPED INTO MAINLY THE 20S OVERNIGHT
WITH SOME BLACK ICE POSSIBLE LATE TONIGHT AS ANY MOISTURE WILL
FREEZE ON UNTREATED SURFACES.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH SATURDAY NIGHT/...
FLOW ACROSS REGION WILL SHIFT TO THE NORTHWEST AS THE LOW MOVES
NORTHEAST AWAY FROM THE REGION. ALOFT THE UPPER TROUGH AXIS WILL
SWING THROUGH MAINLY DURING THE MORNING AND CYCLONIC WILL SET UP
ACROSS THE REGION. COLDER AIR MASS WILL BLANKET REGION WITH 850 MB
TEMPERATURES DROPPING TO -10 TO -12 DEGREES CELSIUS ACROSS THE
FORECAST AREA. WITH THIS COLD AIR MOVING ACROSS THE GREAT LAKES
LAKE EFFECT CLOUDS AND SHOWERS IMPACTING PORTIONS OF THE FORECAST
AREA...MAINLY THE WESTERN MOHAWK VALLEY INTO THE EASTERN CATSKILLS.
THE LAKE EFFECT WILL DIMINISH SATURDAY AND SHOULD COME TO AN END
BY SATURDAY NIGHT AS RIDGING BUILDS IN. THE RIDGE`S VISIT WILL BE
BRIEF AS IT MOVES QUICKLY OFFSHORE SATURDAY NIGHT AHEAD OF THE
NEXT SYSTEM.
COLD WITH TEMPERATURES RUNNING 10 TO 15 DEGREES BELOW NORMAL.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
A VERY ACTIVE AND CHILLY PATTERN SETTING UP FOR THE LONG TERM PERIOD
AS A VIGOROUS UPPER TROUGH /POLAR VORTEX/ DIVES SOUTHWARD AND
EASTWARD OF THE CONTINENTAL DIVIDE.
MONDAY...PLENTY OF MODEL DISCREPANCIES REMAIN AS THE ECMWF REMAINS
ON THE WARMER SIDE OF THE GUIDANCE ENVELOPE WITH THE GGEM/GFS ON THE
COLDER SIDE. IN ADDITION...THE GGEM IS STRONGER WITH THE COASTAL
WAVE REFLECTION AS OPPOSED TO THE FLATTER AND FASTER WAVE OF THE GFS
WITH THE ECMWF SOMEWHAT IN THE MIDDLE. AT THIS TIME...AND PER
COLLABORATION WITH WPC...WE WILL LEAN TOWARD THE MORE STABLE ECMWF.
THIS WOULD RESULT THE CHANCE FOR ACCUMULATING SNOW FOR THE HIGHER
TERRAIN NORTH AND WEST OF ALBANY WITH MAINLY RAIN /PERHAPS A LITTLE
SNOW MIX/ SOUTH AND EAST OF ALBANY. FOR NOW...WE WILL HAVE HIGH
CHANCE POPS UNDER A CLOUDY SKY. WPC GUIDANCE TEMPS ARE A GREAT
COMPROMISE WITH LEANING TOWARD A SLIGHTLY COLDER SOLUTION DUE TO WET
BULB PROCESS.
MONDAY NIGHT THROUGH WEDNESDAY...WHAT WAVE DOES DEVELOP WILL QUICKLY
TRACK TO THE NORTHEAST MONDAY EVENING. COLD AIR ADVECTION AND DEEP
CYCLONIC FLOW WILL RESULT IN LAKE EFFECT ACTIVITY DEVELOPING
DOWNWIND OF LAKE ONTARIO WHICH WILL BE THE MAIN WEATHER STORY FOR
THE REMAINDER OF THE LONG TERM PERIOD. OTHERWISE...BELOW NORMAL
TEMPERATURES AS H850 TEMPS ARE AT OR BELOW -10C AND MAINLY CLOUD
COVERAGE INTO THE TERRAIN WITH UPSLOPE CONDITIONS. MORE CLEARING
WILL TAKE PLACE DOWNWIND OF THE TERRAIN...ESPECIALLY IN THE MID
HUDSON VALLEY.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
THE COMBINATION OF AN UPPER LEVEL TROUGH APPROACHING FROM THE
WEST...AND A WEAK LOW PRESSURE SYSTEM OFF THE EAST COAST...HAS
ALLOWED FOR PERIODS OF LIGHT SNOW TO DEVELOP ACROSS KALB/KPOU AND
KPSF.
THE MAIN BAND OF PRECIP...MAINLY IN THE FORM OF SNOW...CONTINUES
TO SLOWLY MOVE E/SE...WITH THE MAIN FOCUS BEGINNING TO SHIFT
MAINLY EAST OF THE HUDSON RIVER. WIDESPREAD IFR VSBYS AND SOME
CIGS ARE OCCURRING WITHIN THIS BAND. THE BAND REMAINS S AND E OF
KGFL...WHERE MAINLY VFR CONDITIONS ARE EXPECTED THROUGH DAYBREAK.
OVER THE NEXT 1-3 HOURS...WE EXPECT IFR CONDITIONS TO GRADUALLY
IMPROVE TO MVFR AT KALB...AS THE SNOW TAPERS OFF TO FLURRIES. AT
KPSF AND KPOU...PERIODS OF SNOW MAY PERSIST THROUGH AROUND
08Z/FRI...SO MAINLY IFR CONDITIONS ARE EXPECTED DURING THIS
TIME...BEFORE IMPROVING TO MVFR AFTER 08Z/FRI.
AFTER 09Z...MVFR/VFR CONDITIONS ARE EXPECTED...MAINLY DUE TO
CIGS. SOME SNOW SHOWERS OR FLURRIES MAY REDEVELOP AT KGFL...AND
COULD OCCASIONALLY DRIFT INTO KALB AND KPSF THROUGH MID MORNING.
THIS COULD ALLOW FOR SOME BRIEF REDUCTIONS TO MVFR OR IFR.
OTHERWISE...MAINLY VFR CONDITIONS ARE EXPECTED THROUGH 06Z/SAT.
LIGHT/VARIABLE WINDS WILL TREND INTO THE WEST TO NORTHWEST BY
SUNRISE AT 5-10 KT. W/NW WINDS WILL THEN INCREASE SLIGHTLY TO 8-12
KT BY MID MORNING...WITH SOME GUSTS DEVELOPING IN THE 15-20 KT
RANGE...PERHAPS A BIT HIGHER AT KALB AND KPSF. NW WINDS SHOULD
THEN DECREASE TO LESS THAN 8 KT 1-2 HOURS AFTER SUNSET.
OUTLOOK...
FRI NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN.
SAT-SAT NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SUN: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA...SHSN.
SUN NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...SHSN.
MON: HIGH OPERATIONAL IMPACT. LIKELY RA...SN.
MON NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN.
TUESDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
NO HYDROLOGIC PROBLEMS ARE EXPECTED INTO EARLY NEXT WEEK.
MAINLY LIGHT AND FROZEN PRECIPITATION INTO THE WEEKEND. A STORM
SYSTEM WILL IMPACT THE REGION TO END THE WEEKEND AND START THE NEW
WORK WEEK. THERE IS MUCH UNCERTAINTY WITH THE SYSTEM...REFER TO THE
LONG TERM DISCUSSION FOR DETAILS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...IAA
NEAR TERM...LFM/BGM/11
SHORT TERM...IAA
LONG TERM...BGM
AVIATION...ELH/KL
HYDROLOGY...IAA
AREA FORECAST DISCUSSION
NWS ALBANY NY
1224 AM EST FRI NOV 14 2014
.SYNOPSIS...
FIRST MEASURABLE SNOWFALL FOR MUCH OF THE FORECAST AREA EXPECTED
TONIGHT WITH ACCUMULATIONS MAINLY ON GRASSY SURFACES. SNOW IS
EXPECTED TO COME TO AN END BEFORE THE MORNING COMMUTE. IN THE
MEANTIME...LAKE ENHANCED SNOW WILL CONTINUE INTO THE WESTERN
ADIRONDACKS. A REINFORCING SHOT OF COLD AIR WILL TAKE HOLD FRIDAY
AND LAST INTO THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1215 AM...A BAND OF STEADY LIGHT SNOW IS PROGRESSING
EASTWARD ACROSS THE GREATER CAPITAL DISTRICT AND POINTS SOUTH AND
EAST. LATEST LOCAL HRRR MODEL AND HIRESWRF MODEL RUN UPDATES HAVE
BEEN CONSISTENT WITH SLIGHTLY MORE QPF ACROSS THE SOUTHERN REGIONS
WHERE SNOWFALL TOTALS HAVE BEEN INCREASED SLIGHTLY IN THE HIGHEST
TERRAIN ACROSS THE SOUTHERN BERKSHIRES INTO THE NORTHERN
LITCHFIELD HILLS WILL RANGE BETWEEN ONE TO TWO INCHES WITH
ISOLATED AREAS UP TO THREE INCHES POSSIBLE BY EARLY FRIDAY
MORNING.
THE PRECIPITATION MAINLY IN THE FORM OF SNOW IS EXPECTED TO END
BEFORE THE MORNING COMMUTE...BY AROUND 07Z ACROSS OUR WESTERN NEW
ENGLAND COUNTIES. GENERALLY LOOKING AT LESS THAN AN INCH BELOW
1000 FEET WITH 1 TO 2 INCHES ABOVE 1000 FEET AND FOR LITCHFIELD
COUNTY.
LAKE ENHANCED SNOW WILL CONTINUE INTO THE WESTERN ADIRONDACKS
TONIGHT AS THE SOUTHWESTERLY FLOW CONTINUES AHEAD OF APPROACHING
TROUGH. AMOUNTS ARE GENERALLY EXPECTED TO BE LIGHT ACROSS THIS
AREA MAINLY UNDER 2 INCHES.
TEMPERATURES ARE EXPECTED TO DROPPED INTO MAINLY THE 20S OVERNIGHT
WITH SOME BLACK ICE POSSIBLE LATE TONIGHT AS ANY MOISTURE WILL
FREEZE ON UNTREATED SURFACES.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH SATURDAY NIGHT/...
FLOW ACROSS REGION WILL SHIFT TO THE NORTHWEST AS THE LOW MOVES
NORTHEAST AWAY FROM THE REGION. ALOFT THE UPPER TROUGH AXIS WILL
SWING THROUGH MAINLY DURING THE MORNING AND CYCLONIC WILL SET UP
ACROSS THE REGION. COLDER AIR MASS WILL BLANKET REGION WITH 850 MB
TEMPERATURES DROPPING TO -10 TO -12 DEGREES CELSIUS ACROSS THE
FORECAST AREA. WITH THIS COLD AIR MOVING ACROSS THE GREAT LAKES
LAKE EFFECT CLOUDS AND SHOWERS IMPACTING PORTIONS OF THE FORECAST
AREA...MAINLY THE WESTERN MOHAWK VALLEY INTO THE EASTERN CATSKILLS.
THE LAKE EFFECT WILL DIMINISH SATURDAY AND SHOULD COME TO AN END
BY SATURDAY NIGHT AS RIDGING BUILDS IN. THE RIDGE`S VISIT WILL BE
BRIEF AS IT MOVES QUICKLY OFFSHORE SATURDAY NIGHT AHEAD OF THE
NEXT SYSTEM.
COLD WITH TEMPERATURES RUNNING 10 TO 15 DEGREES BELOW NORMAL.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
A VERY ACTIVE AND CHILLY PATTERN SETTING UP FOR THE LONG TERM PERIOD
AS A VIGOROUS UPPER TROUGH /POLAR VORTEX/ DIVES SOUTHWARD AND
EASTWARD OF THE CONTINENTAL DIVIDE.
MONDAY...PLENTY OF MODEL DISCREPANCIES REMAIN AS THE ECMWF REMAINS
ON THE WARMER SIDE OF THE GUIDANCE ENVELOPE WITH THE GGEM/GFS ON THE
COLDER SIDE. IN ADDITION...THE GGEM IS STRONGER WITH THE COASTAL
WAVE REFLECTION AS OPPOSED TO THE FLATTER AND FASTER WAVE OF THE GFS
WITH THE ECMWF SOMEWHAT IN THE MIDDLE. AT THIS TIME...AND PER
COLLABORATION WITH WPC...WE WILL LEAN TOWARD THE MORE STABLE ECMWF.
THIS WOULD RESULT THE CHANCE FOR ACCUMULATING SNOW FOR THE HIGHER
TERRAIN NORTH AND WEST OF ALBANY WITH MAINLY RAIN /PERHAPS A LITTLE
SNOW MIX/ SOUTH AND EAST OF ALBANY. FOR NOW...WE WILL HAVE HIGH
CHANCE POPS UNDER A CLOUDY SKY. WPC GUIDANCE TEMPS ARE A GREAT
COMPROMISE WITH LEANING TOWARD A SLIGHTLY COLDER SOLUTION DUE TO WET
BULB PROCESS.
MONDAY NIGHT THROUGH WEDNESDAY...WHAT WAVE DOES DEVELOP WILL QUICKLY
TRACK TO THE NORTHEAST MONDAY EVENING. COLD AIR ADVECTION AND DEEP
CYCLONIC FLOW WILL RESULT IN LAKE EFFECT ACTIVITY DEVELOPING
DOWNWIND OF LAKE ONTARIO WHICH WILL BE THE MAIN WEATHER STORY FOR
THE REMAINDER OF THE LONG TERM PERIOD. OTHERWISE...BELOW NORMAL
TEMPERATURES AS H850 TEMPS ARE AT OR BELOW -10C AND MAINLY CLOUD
COVERAGE INTO THE TERRAIN WITH UPSLOPE CONDITIONS. MORE CLEARING
WILL TAKE PLACE DOWNWIND OF THE TERRAIN...ESPECIALLY IN THE MID
HUDSON VALLEY.
&&
.AVIATION /05Z FRIDAY THROUGH TUESDAY/...
PERIOD OF LIGHT WINTRY MIXTURE CHANGING TO MAINLY SNOW TONIGHT FOR
TAF SITES. THE INITIAL VFR CONDITIONS WILL GRADUALLY DETERIORATE TO
MVFR LATER THIS EVENING. THERE COULD BE A PERIOD OF IFR CONDITIONS
AT KPOU AS BANDED PRECIP MAY LIMIT BOTH VIS AND CIGS.
OVERNIGHT...THE COASTAL SYSTEM WILL RAPIDLY PULL AWAY AS IMPROVING
CONDITIONS WILL OCCUR WITH RESPECT TO DIMINISHING SNOW AND IMPROVING
VISIBILITIES. HOWEVER...CIGS WILL REMAIN AT OR WITH MVFR RANGE THE
REMAINDER OF THE NIGHT.
DURING FRIDAY...WEST-NORTHWEST WINDS WILL INCREASE WHICH WILL ASSIST
WITH CIGS BREAKING UP TO VFR CONDITIONS. HOWEVER...UPSLOPE
CONDITIONS FOR KPSF MAY HOLD ONTO THE BKN CIGS A BIT LONGER.
OUTLOOK...
FRI NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN.
SAT-SAT NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SUN: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA...SHSN.
SUN NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...SHSN.
MON: HIGH OPERATIONAL IMPACT. LIKELY RA...SN.
MON NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN.
TUESDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
NO HYDROLOGIC PROBLEMS ARE EXPECTED INTO EARLY NEXT WEEK.
MAINLY LIGHT AND FROZEN PRECIPITATION INTO THE WEEKEND. A STORM
SYSTEM WILL IMPACT THE REGION TO END THE WEEKEND AND START THE NEW
WORK WEEK. THERE IS MUCH UNCERTAINTY WITH THE SYSTEM...REFER TO THE
LONG TERM DISCUSSION FOR DETAILS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...IAA
NEAR TERM...LFM/BGM/11
SHORT TERM...IAA
LONG TERM...BGM
AVIATION...ELH
HYDROLOGY...IAA
AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
840 PM EST SAT NOV 15 2014
.UPDATE...SURFACE HIGH TO THE NORTH AND INVERTED TROUGH OFF THE
EAST COAST HAS A MODERATE NE FLOW OVER NE FL/SE GA. LOW CLOUDS
HAVE SPREAD ACROSS THE AREA IN SHALLOW NE FLOW BELOW INVERSION.
EXPECT CLOUDS TO PERSIST OVER THE AREA TONIGHT AND SUNDAY MORNING.
MODELS SHOW A WEAK SURFACE LOW FORMING OVER THE WATERS TONIGHT AND
MOVING OFF TO THE NE ON SUNDAY. LIGHT RADAR ECHOES OFF THE
FLAGLER/ST. JOHNS COUNTY COASTLINE WILL LIKELY MOVE INTO COASTAL
COUNTIES TONIGHT PRODUCING LIGHT RAIN SHOWERS AND/OR DRIZZLE.
&&
.AVIATION...
LOW MVFR CEILINGS PERSIST ACROSS THE AREA AS WEAK LOW PRESSURE
DEVELOPS OVER OUR ADJACENT COASTAL WATERS. THE HRRR MODEL INSISTS
ON BREAKING UP THE MVFR CLOUD DECK OVERNIGHT BUT THAT SOLUTION IS
CLEARLY AN OUTLIER AT THIS POINT. THE BULK OF THE DATA SUPPORTS
KEEPING THE LOW CEILINGS IN PLACE ALL NIGHT. IN FACT...THE
CEILINGS MAY LOWER AS WE GO THROUGH THE NIGHT WITH SOME
DRIZZLE/LIGHT SHOWERS POSSIBLE AT TERMINALS ALONG THE COAST. IFR
CONDITIONS ARE CERTAINLY POSSIBLE BUT WE WILL LIMIT RESTRICTIONS
TO LOW MVFR FOR NOW. CONFIDENCE MAY BECOME HIGH ENOUGH WHEN WE
ISSUE THE 6Z TAFS TO SHOW A PERIOD OF IFR CONDITIONS FOR A FEW
HOURS AROUND SUNRISE. CONDITIONS ARE EXPECTED TO IMPROVE TO VFR
FROM SOUTH TO NORTH BY MID TO LATE SUNDAY MORNING.
&&
.MARINE...NE WINDS STILL AROUND 20 KNOTS WITH HIGHER GUSTS AND
SEAS AROUND 6 FEET. MODERATE NE FLOW WILL DECREASE LATER TONIGHT
AS A WEAK SURFACE LOW DEVELOPS OVER THE WATERS DECREASING THE
PRESSURE GRADIENT. WILL CONTINUE ADVISORY UNTIL 08Z.
RIP CURRENTS: MODERATE RISK WITH ONSHORE WINDS AND 4-5 FOOT
BREAKERS.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 42 68 56 74 / 10 10 20 70
SSI 51 67 60 76 / 20 20 10 60
JAX 49 72 58 80 / 20 10 10 60
SGJ 56 72 62 80 / 20 10 10 60
GNV 50 76 58 79 / 10 0 10 60
OCF 53 79 60 81 / 0 0 10 60
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GA...NONE.
AM...SMALL CRAFT ADVISORY UNTIL 3 AM EST SUNDAY FOR ALTAMAHA SOUND GA
TO FERNANDINA BEACH FL 20 NM TO 60 NM OFFSHORE-ALTAMAHA
SOUND GA TO FERNANDINA BEACH FL OUT 20 NM-FERNANDINA BEACH
TO ST AUGUSTINE FL 20 NM TO 60 NM OFFSHORE-FERNANDINA BEACH
TO ST AUGUSTINE FL OUT 20 NM-ST AUGUSTINE TO FLAGLER BEACH
FL 20 NM TO 60 NM OFFSHORE-ST AUGUSTINE TO FLAGLER BEACH FL
OUT 20 NM.
&&
$$
ZIBURA/SHULER/WALSH
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
1038 AM EST FRI NOV 14 2014
.SYNOPSIS...
A LARGE AREA OF CANADIAN HIGH PRESSURE WILL BUILD INTO THE REGION
THROUGH SUNDAY. THE HIGH WILL WEAKEN AND RETREAT TO THE NORTHEAST
SUNDAY NIGHT IN ADVANCE OF A LOW PRESSURE SYSTEM AND STRONG COLD
FRONT EXPECTED TO AFFECT THE AREA ON MONDAY. ANOTHER AREA OF COLD
CANADIAN HIGH PRESSURE WILL BUILD IN STARTING TUESDAY AND PREVAIL
THROUGH LATE NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
THE LEADING EDGE OF THE COLD CANADIAN AIRMASS HAS DROPPED THROUGH
MUCH OF THE FORECAST AREA THIS MORNING. HOWEVER...THUS FAR THE
COLD LAYER IS ONLY ABOUT 2500 FT DEEP...AND DEEP WESTERLY FLOW
ABOVE THAT IS PRODUCING A LARGE AREA OF LOW STRATUS ACROSS
SOUTHERN SC AND INLAND GA. A SECONDARY DRY FRONT WILL DROP THROUGH
THE AREA DURING THE AFTERNOON WITH MODEL SOUNDINGS SHOWING THE
CLOUD- PRODUCING MOISTURE LAYER DISSIPATING BY SUNSET. IN THE
MEANTIME THE LOW STRATUS WILL CONTINUE TO MOVE SOUTH AND AFFECT
MOST OF OUR AREA BY EARLY AFTERNOON AS THE PRELIMINARY WIND SHIFT
OCCURS. NEEDLESS TO SAY THE COMBINATION OF LOW-LEVEL COLD
ADVECTION AND SUN-BLOCKING STRATUS WILL KEEP TEMPERATURES FROM
RISING MUCH TODAY...EXCEPT ACROSS OUR FAR SOUTHERN ZONES WHERE
FULL SUNSHINE AND NW FLOW ALLOWS TEMPS TO RISE INTO THE MID/UPPER
50S. A BRIEF RISE TO LOWER 50S TEMPS IN SOUTHERN SC WILL
TRANSITION TO A SLOW COOLING TREND WITH VALUES DROPPING INTO THE
UPPER 40S DURING THE AFTERNOON.
STRONG COLD AIR ADVECTION CONTINUES INTO TONIGHT WITH 5-10 MPH
NORTHERLY FLOW PERSISTING. ALTHOUGH THE MIXED BOUNDARY LAYER WILL
REDUCE THE EFFECTS OF RADIATIONAL COOLING...CLEAR SKIES WILL ONLY
HELP TEMPS PLUMMET AFTER DARK. WE ARE STILL SHOWING OVERNIGHT LOWS
IN THE UPPER 20S FAR INLAND WITH READINGS AT OR SLIGHTLY BELOW
FREEZING IN MANY LOCATIONS AWAY FROM THE GA COAST AND SC BEACHES.
FREEZE WATCHES IN PLACE FOR ALL BUT THE IMMEDIATE COASTAL ZONES OF
SE GEORGIA.
LAKE WINDS...WE STILL ARE FORECASTING FREQUENT WIND GUSTS JUST BELOW
ADVISORY CRITERIA ON LAKE MOULTRIE BUT WILL MAINTAIN MENTION OF THE
POSSIBILITY IN THE HAZARDOUS WEATHER OUTLOOK SINCE OCCASIONAL GUSTS
TOPPING 25 KT ARE POSSIBLE.
&&
.SHORT TERM /SATURDAY THROUGH MONDAY/...
SATURDAY AND SATURDAY NIGHT...A FAST NEARLY ZONAL FLOW WILL PREVAIL
ALOFT AS COLD HIGH PRESSURE AT THE SURFACE BECOMES POSITIONED JUST
TO THE NORTH. DEEP DRY AIR WILL PREVAIL THROUGH THE DAY AND A DRY
FORECAST IS IN PLACE. THE MAIN STORY FOR THE DAY WILL BE THE VERY
COLD AIR WITH HIGHS STRUGGLING TO REACH THE LOW 50S TO THE NORTH AND
MID 50S TO THE SOUTH. SUCH VALUES WOULD BE NEARLY 20 DEGREES BELOW
NORMAL FOR MID NOVEMBER. THEN LATE IN THE DAY SATURDAY AND THROUGH
THE OVERNIGHT...THE SURFACE PATTERN WILL BEGIN TO TAKE ON A MORE
WEDGE LIKE PATTERN. IN FACT...A INCREASINGLY DISCERNIBLE COASTAL
TROUGH LOOKS AS THOUGH IT WILL TAKE SHAPE WITH INCREASING LOW LEVEL
MOISTURE NOTED IN MODEL SOUNDINGS AND TIME HEIGHTS. LAND AREAS WILL
MAINLY BE DRY...BUT THE ADJACENT COASTAL WATERS WILL BEGIN TO SEE AN
INCREASE IN SHOWER ACTIVITY WITHIN THE LOW LEVEL CONVERGENCE IN THE
DEVELOPING TROUGH. LOWS WILL FALL INTO THE UPPER 30S
INLAND...RANGING TO THE LOW TO MID 40S AT THE COAST.
SUNDAY AND MONDAY...THE OVERALL PATTERN BECOMES A BIT MORE COMPLEX.
SUNDAY INCREASINGLY LOOKS LIKE A WEDGE DAY AS THE MAIN PARENT HIGH
SLIPS OFF THE BUT CONTINUES TO RIDGE INTO THE CAROLINAS AND GEORGIA.
THE INLAND WEDGE WILL BE REINFORCED BY THE COASTAL TROUGH AS WELL AS
THROUGH DIABATIC PROCESSES ASSOCIATED WITH LIGHT PRECIPITATION
SPREADING INTO LAND AREAS BEGINNING SUNDAY MORNING. THIS COLD AIR
DAMMING REGIME WILL NECESSITATE LOWERING SUNDAY HIGH TEMPS RATHER
SIGNIFICANTLY. HIGHS HAVE BEEN LOWERED INTO THE UPPER 50S INLAND TO
AROUND 60 AT THE COAST WITH THIS FORECAST PACKAGE...AND THIS MAY BE
A BIT OPTIMISTIC. FURTHER DOWNWARD ADJUSTMENTS MAY BE NEEDED WITH
SUBSEQUENT UPDATES. AT SOME POINT SUNDAY NIGHT INTO MONDAY...THE
WEDGE WILL ERODE AS THE HIGH WEAKENS AND THE DEVELOPING AREA OF LOW
PRESSURE ACROSS THE LOWER MISSISSIPPI VALLEY LIFTS A WARM FRONT
THROUGH THE AREA. THE MOST ACTIVE WEATHER DAY WILL THEN BE MONDAY AS
SHORTWAVE ENERGY TRANSLATES ACROSS THE REGION ASSOCIATED WITH A DEEP
AND COLD TROUGH ACROSS THE GREAT LAKES REGION. THE AFOREMENTIONED
SURFACE LOW WILL QUICKLY LIFT NORTHEASTWARD IN THE LEE OF THE
APPALACHIANS ALONG A SHARPENING FRONTAL ZONE. DEEP MOISTURE WILL
INCREASE ACROSS THE AREA AND A QUICK SHOT OF UPPER JET DYNAMICS WILL
SPREAD IN THROUGH THE DAY ON MONDAY. MODELS CONTINUE TO LOOK WET FOR
MONDAY AND POPS HAVE BEEN RAISED TO LIKELY. THE DYNAMICS WITH THIS
SYSTEM CONTINUE TO LOOK STRONG...BUT THE POTENTIAL FOR SURFACE
DESTABILIZATION IS LIMITED. TEMPS BEHIND THE WARM FRONT WILL WARM
INTO THE 70 DEGREE RANGE BUT IT LOOKS AS THOUGH INSTABILITY WILL BE
LOW ENOUGH TO PRECLUDE A SEVERE THREAT. THERE COULD STILL BE AN
ISOLATED EMBEDDED THUNDERSTORM SO THE FORECAST STILL FEATURES
ISOLATED THUNDER MONDAY AFTERNOON.
&&
.LONG TERM /MONDAY NIGHT THROUGH THURSDAY/...
OVERALL CONFIDENCE IN THE LONG TERM FORECAST PERIOD IS QUITE HIGH
AND THE MAIN STORY WILL BE THE IMPRESSIVE SHOT OF COLD AIR THAT IS
PROGGED TO IMPACT THE SOUTHEAST CONUS. COLD ADVECTION WILL BEGIN
MONDAY NIGHT IN THE WAKE OF THE STRONG COLD FRONT AND TEMPERATURES
LOOK VERY CHILLY TUESDAY ONWARD. CONFIDENCE IS INCREASING THAT THE
COLDEST AIR OF THE SEASON THUS FAR WILL INFILTRATE THE AREA TUESDAY
NIGHT THROUGH WEDNESDAY NIGHT. A HARD ADVECTIVE FREEZE WILL LIKELY
IMPACT THE FORECAST AREA TUESDAY NIGHT WITH LOWS IN THE MID TO UPPER
20S JUST ABOUT EVERYWHERE OUTSIDE THE BEACHES. HIGHS ON WEDNESDAY
WILL THEN BE IMPRESSIVELY CHILLY WITH RAW THICKNESS VALUES ONLY
SUPPORTING HIGHS IN THE LOW 40S. THE FORECAST HAS BEEN TRENDED LOWER
AND FEATURES UPPER 40S FOR NOW. THEN WEDNESDAY NIGHT...ANOTHER HARD
FREEZE WILL OCCUR AS EXCELLENT RADIATIONAL COOLING CONDITIONS SET UP
WITH THE SURFACE HIGH POSITIONED RIGHT OVER SOUTH GEORGIA.
OVERALL...IT APPEARS TEMPERATURES WILL BE NEAR RECORD LOWS AND
RECORD LOW MAX VALUES FOR TUESDAY NIGHT THROUGH WEDNESDAY NIGHT.
&&
.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
A LARGE AREA OF MVFR STRATUS CONTINUES TO OOZE TO THE SOUTH THIS
MORNING IN ASSOCIATION WITH A WEAK TROUGH TRAILING THE COLD FRONT.
THE LATEST HRRR MODEL SHOWS THIS CLOUD DECK STAYING WITH US IN
SOUTHERN SC THROUGH THE MIDDLE OF THE AFTERNOON THOUGH CURRENT
TRENDS INDICATE THE CEILING WILL LIFT TO VFR BY EARLY AFTERNOON.
MEANWHILE THE LEADING EDGE WILL OVERSPREAD THE SAV TERMINAL BY 16Z
AND PERSIST INTO EARLY AFTERNOON BEFORE SCATTERING OUT.
ALL INDICATIONS ARE THAT THE CLOUDS WILL BE OUT OUR HAIR BY SUNSET
WITH VFR CONDITIONS THEREAFTER.
EXTENDED AVIATION OUTLOOK...VFR SATURDAY...THEN INCREASING
CHANCES FOR FLIGHT RESTRICTIONS IN DEVELOPING CEILINGS LATE
SATURDAY NIGHT AND SUNDAY. PREVAILING VFR CONDITIONS WILL RETURN
BEHIND A DEPARTING LOW PRESSURE SYSTEM AND COLD FRONT MONDAY NIGHT
AND INTO TUESDAY.
&&
.MARINE...
THE PRELIMINARY BLAST OF COLD ADVECTION HAS SURGED THROUGH THE
WATERS EARLY THIS MORNING. SURFACE OBS INDICATE WINDS HAVE
REMAINED BELOW SMALL CRAFT ADVISORY CRITERIA IN ALL NEARSHORE
WATERS OVERNIGHT AND THIS MORNING. HOWEVER SOME GUSTS TO 25 KT
HAVE LIKELY OCCURRED OVER THE OFFSHORE GA WATERS WHERE WARMER
WATER EXISTS. THE LATEST HIGH-RES MODEL DATA INDICATES WE COULD
SEE SOME 25 KT GUSTS OVER THE CHARLESTON NEARSHORE WATERS LATE
THIS AFTERNOON INTO TONIGHT SO WE PUSHED BACK THE SMALL CRAFT
ADVISORY START TIME FOR THOSE WATERS UNTIL 5 PM...AND DROPPED THE
ADVISORY FOR THE REMAINDER OF THE NEARSHORE WATERS.
SATURDAY THROUGH TUESDAY...HIGH PRESSURE WILL SLIDE BY TO THE
NORTH OF THE REGION ON SATURDAY. CONDITIONS WILL BE NEAR SMALL
CRAFT ADVISORY THRESHOLDS FOR THE NEAR SHORE WATERS EARLY ON
SATURDAY BUT WILL THEN DIMINISH AS THE PRESSURE GRADIENT RELAXES A
BIT. CONDITIONS WILL STILL BE SUPPORTIVE OF AN ADVISORY FOR THE
OUTER GEORGIA WATERS UNTIL SATURDAY EVENING. A COASTAL TROUGH IS
EXPECTED TO DEVELOP LATE SATURDAY NIGHT AND SUNDAY ACROSS THE
WATERS WITH INCREASING PRECIPITATION CHANCES. THE FLOW WILL THEN
TURN MORE SOUTHERLY SUNDAY NIGHT AS A WARM FRONT LIFTS THROUGH THE
WATERS IN ADVANCE OF A DEVELOPING LOW PRESSURE SYSTEM AND COLD
FRONT TO THE WEST. MARGINAL SMALL CRAFT CONDITIONS COULD DEVELOP
IN THE INCREASING SOUTHERLY FLOW MONDAY...BUT APPEAR MORE LIKELY
IN THE COLD ADVECTION NORTHWEST FLOW BEHIND THE FRONT MONDAY NIGHT
AND TUESDAY.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...FREEZE WATCH FROM LATE TONIGHT THROUGH SATURDAY MORNING FOR
GAZ087-088-099>101-114>116-118-137-138.
SC...FREEZE WATCH FROM LATE TONIGHT THROUGH SATURDAY MORNING FOR
SCZ040-042>045-047>052.
MARINE...SMALL CRAFT ADVISORY FROM 5 PM THIS AFTERNOON TO NOON EST
SATURDAY FOR AMZ350.
SMALL CRAFT ADVISORY UNTIL 7 PM EST SATURDAY FOR AMZ374.
&&
$$
NEAR TERM...JRL
SHORT TERM...BSH
LONG TERM...BSH
AVIATION...JRL
MARINE...BSH/JRL
AREA FORECAST DISCUSSION
NWS GOODLAND KS
407 PM MST SAT NOV 15 2014
.UPDATE...
ISSUED AT 407 PM MST SAT NOV 15 2014
MINOR UPDATE TO POP/WX TO REFLECT CURRENT LIGHT SNOW COVERAGE ON
RADAR AND AMEND SNOW AMOUNT FORECAST FOR RATES ADVERTISED ON
CURRENT HIGH RES GUIDANCE (WHICH SEEMS TO HAVE GOOD HANDLE ON
CURRENT COVERAGE/RATES). OVERALL KEEPS A SIMILAR PICTURE WITH MOST
LOCATIONS ONLY RECEIVING AROUND HALF AN INCH...THOUGH GUIDANCE IS
SHOWING THIS BAND OF LIGHT SNOW TRAINING OVER OUR SOUTHWEST
THROUGH THE NIGHT...AND I COULDNT RULE OUT 1-2 INCHES IN CHEYENNE
COUNTY COLORADO AND GREELEY/WICHITA COUNTIES IN KANSAS.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 210 PM MST SAT NOV 15 2014
THE UPPER TROUGH AXIS MOVES SOUTH ACROSS THE CENTRAL PLAINS TONIGHT
AND SUNDAY WITH NORTHWEST FLOW FOLLOWING. SURFACE HIGH PRESSURE
WILL BUILD SOUTHEAST INTO THE CENTRAL PLAINS THROUGH THIS TIME.
PLAN TO GO WITH CHANCE AND LIKELY POPS TONIGHT ACROSS THE FA AS
DYNAMICS AND MOISTURE MOVE FROM NORTH TO SOUTH. THE DYNAMICS MOVE
INTO THE SOUTHWEST PORTION OF THE FA AFTER 06Z AND SO WILL SHIFT
LIKELY POPS OVER THE EXTREME SOUTHWEST AFTER MIDNIGHT WITH
DECREASING POPS TO THE NORTH. MOISTURE IS LIMITED WITH THIS SYSTEM
SO WILL KEEP SNOW AMOUNTS ON THE LIGHT SIDE OR A FEW TENTHS OF AN
INCH. THE SOUTHWEST WILL HAVE THE BEST CHANCE OF ACCUMULATING SNOW
WITH AROUND A HALF INCH POSSIBLE THERE.
MIN TEMPERATURES WILL FALL INTO THE SINGLE DIGITS OVERNIGHT AND WITH
NORTHWEST WIND SOME VERY COLD WIND CHILL TEMPERATURES WILL BE
REACHED. WIND CHILL TEMPERATURES DROP BELOW WIND CHILL ADVISORY
CRITERIA TONIGHT AND SUNDAY MORNING ACROSS THE NORTH AND WEST ZONES.
PLAN TO ISSUE A WIND CHILL ADVISORY TO COVER THIS. SEE DETAILS
BELOW. MAX TEMPERATURES SUNDAY SHOULD RISE TO THE UPPER 20S WITH
TEMPERATURES NEAR 30 OVER THE SOUTHEAST ZONES.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 210 PM MST SAT NOV 15 2014
SEVERAL DRY DAYS ARE EXPECTED FOR THE ENTIRE FORECAST AREA GOING
INTO THE BEGINNING OF NEXT WEEK. THE TRI STATE REGION WILL BE IN
BETWEEN A BROAD/DEEP 500 MB TROUGH THAT SETS UP OVER THE EASTERN
PORTION OF THE COUNTRY SUNDAY NIGHT INTO MONDAY...AND A BUILDING H5
RIDGE OVER THE WESTERN HALF OF THE COUNTRY. RIDGE DOES SHIFT
EASTWARD INTO THE ROCKIES BY MIDWEEK..WITH 500/700 MB TROUGH COMING
OFF THE PACIFIC AND THRU RIDGE...INTO ROCKIES LATE FRIDAY INTO
SATURDAY.
DOWN TO THE SURFACE...HIGH PRESSURE WILL BE MOST PREVALENT DURING
THIS TIMEFRAME. ONLY CHANCE FOR PRECIPITATION BEFORE NEXT WEEKEND
WILL BE ON WEDNESDAY AS FRONTAL BOUNDARY/TROUGH SHIFTS OFF THE
ROCKIES AND EASTWARD TO THE MISSISSIPPI VALLEY. WITH HIGH PRESSURE
SE OF THE AREA DURING THIS TIME AND BROAD WNW FLOW...LITTLE QPF
POTENTIAL...SO WILL HAVE DRY. THE NEXT CHANCE FOR PRECIPITATION WILL
BE AT THE END OF NEXT WEEK WHEN MID LEVEL SHORTWAVE MOVES EAST OFF
THE PACIFIC. DRY AIR OUT AHEAD OF IT...COMBINED WITH ITS TRIP THRU
THE ROCKIES...WILL LIMIT QPF POTENTIAL BUT OUTSIDE CHANCE OF A FEW
LATE DAY SHOWERS.
WITH LACK OF ANY APPRECIABLE RAIN OR SNOW NEXT WEEK...THE MAIN
FOCUS WILL BE SHIFT IN TEMPERATURES. WITH 850/925 MB TEMPS RANGING
FROM -2C TO -4C ON MONDAY...UP TO +9C TO +12C ON FRIDAY INTO
SATURDAY...THE FORECAST AREA WILL SEE BELOW NORMAL TEMPS SHIFTING TO
ABOVE NORMAL READINGS ESPECIALLY DURING THE DAY. TRI STATE REGION
WILL SEE HIGHS NEAR 30F ON MONDAY TO MID 40S BY MIDWEEK TO ALMOST
MID 50S FOR THE END OF NEXT WEEK. THIS WOULD GIVE WEDNESDAY INTO
SATURDAY WITH HIGHS 5 TO 10 DEGREES ABOVE NORMAL. WITH HIGH PRESSURE
MOST PREVALENT...CLEAR SKIES AT NIGHT WILL HAVE OVERNIGHT LOWS
RANGING FROM THE TEENS TO START THE WEEK...TO THE 20S FOR THE REST
OF THE TIME.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1030 AM MST SAT NOV 15 2014
CIGS ARE PROGRESSIVELY LOWERING AT KGLD AND CONTINUE MVFR AT KMCK
AT MIDDAY AS THE UPPER TROUGH MOVES INTO THE NORTHERN AND CENTRAL
PLAINS TODAY. THE SREF AND HRRR BRING A SWATH OF LIGHT SNOW INTO
THE ARE THIS AFTERNOON WHICH SHOULD IMPACT BOTH TERMINALS WITH
MVFR CONDITIONS. LIGHT SNOW SHOULD END AT BOTH SITES EARLY THIS
EVENING WITH VFR CONDITIONS OCCURRING BEHIND THE COLD FRONT.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...WIND CHILL ADVISORY FROM 9 PM MST /10 PM CST/ THIS EVENING TO 9
AM MST /10 AM CST/ SUNDAY FOR KSZ001>003-013.
CO...WIND CHILL ADVISORY FROM 9 PM THIS EVENING TO 9 AM MST SUNDAY
FOR COZ090-091.
NE...WIND CHILL ADVISORY FROM 9 PM MST /10 PM CST/ THIS EVENING TO 9
AM MST /10 AM CST/ SUNDAY FOR NEZ079>081.
&&
$$
UPDATE...DR
SHORT TERM...FS
LONG TERM...JN
AVIATION...FS
AREA FORECAST DISCUSSION
NWS PADUCAH KY
607 PM CST Sat Nov 15 2014
.UPDATE...
Issued at 606 PM CST SAT NOV 15 2014
Small vort along the Arkansas/Missouri border is producing some
showers which should move east during the evening. Leaned heavily
on the HRRR model for movement and location. Precip type is tricky
as we have already had sleet and rain reported with the current
light precip moving through the area. May see snow/sleet/rain
depending upon location. Do not expect much in the way of accumulation.
&&
.SHORT TERM...(Tonight through Monday night)
Issued at 315 PM CST SAT NOV 15 2014
Confidence has increased enough at this point to warrant a Winter
Weather Advisory for all except the southern Pennyrile region of
western KY for the Sunday night time frame. 12z numerical models
continue on track and in decent agreement with timing and QPF
amounts. The main question will be where the snow vs. sleet vs
rain line sets up Sunday evening, and how quickly it will sink
southeast across western KY during the night. Most models have
slowed the cooling aloft significantly enough that areas of the
southern Pennyrile may experience only rain until between midnight
and 4 AM. There may end up being an extended period of sleet over
much of the remainder of western Kentucky before going over to all
snow late in the evening. Areas along the Ohio River will likely
see a quicker transition to snow during the evening, while mostly
snow will fall at most locations north and west of there. When all
is said and done,
Most should wake Monday morning to a good inch or two of snow. The
exception may be the srn Pennyrile, where the transition is
later and more uncertain. Areas just northwest of that region may see
lighter snow totals if sleet ends up prevailing. On the other
hand, the system looks as though it will strengthen a bit as it
pulls northeast Sunday night. Because of this, am a bit concerned
that some areas up in sw IN and nw KY may end up locally closer to
4 inches. Will stick with an advisory for that region for now, and
let future shifts upgrade to warning headlines if this becomes
more apparent.
Wicked cold air for mid November is still slated to drive
southeast into the region behind the system early next week. Most
locations will not get above freezing on Monday. If we end up with
a layer of snow, lows Monday night may dip to near 10 degrees in
some locations.
.LONG TERM...(Tuesday through Saturday)
Issued at 315 PM CST SAT NOV 15 2014
GFS, ECMWF and GEM are in good agreement Monday night through
Wednesday night showing surface high pressure sliding from the
southern Plains across the Gulf Coast states. As the high moves
southeast of our region, a return of southerly flow will help the
unseasonably cold temperatures improve for Wednesday, though
readings will still be well below normal. Models show a weak dry
cold front moving across the the region late Wednesday into
Wednesday night. The wind shift will result in temperatures
dropping back off a few degrees.
For Thursday through Saturday, models diverge drastically with ECMWF
bringing a surface low moving northeast across the PAH forecast area
by 06z Friday. GFS and GEM both show a surface high over the middle
Mississippi Valley at the same time. Model ensembles lean toward
the latest ECMWF and throw in precip chances Thursday through
Saturday. Along with neighboring offices, pulled any precip chances
for Thursday, and toned back on pops a little through the rest of
the forecast. Next question is precip types. Soundings indicate
overall rain or snow, with the only deciding factor being surface
temperatures. Went rain/snow mix Thursday night through Friday
night, then just went rain on Saturday with temperatures reaching
the lower to middle 40s. Overall confidence is low with PoPs, but
believe at this point precip amounts would be minor.
&&
.AVIATION...
Issued at 547 PM CST SAT NOV 15 2014
Main difference and challenge with the 00z Saturday WFO PAH TAF
issuance is the addition of mixed wintry precipitation within the
WFO PAH County Warning area. Initial onset of precipitation
primarily consists of light snow and sleet, changing to a mix of
rain and snow. Kept a mention of a mix through the evening hours.
Overcast VFR ceilings at or above 5Kft should dominate through the
overnight hours, with lower VFR ceilings developing ater 21z
Saturday.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...WINTER WEATHER ADVISORY from 6 PM Sunday to 6 AM CST Monday FOR
ILZ075>078-080>094.
MO...WINTER WEATHER ADVISORY from 6 PM Sunday to 6 AM CST Monday FOR
MOZ076-086-087-100-107>112-114.
IN...WINTER WEATHER ADVISORY from 6 PM Sunday to 6 AM CST Monday FOR
INZ081-082-085>088.
KY...WINTER WEATHER ADVISORY from 6 PM Sunday to 6 AM CST Monday FOR
KYZ001>008-010-011-013>016-018>020.
&&
$$
UPDATE...PS
SHORT TERM...MEFFERT
LONG TERM...RST
AVIATION...Smith
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
1205 AM EST Fri Nov 14 2014
...Updated Aviation Discussion...
...Forecast Update...
Issued at 930 PM EST Thu Nov 13 2014
Have some snow flurries at times passing through the region. RUC
soundings indicate a narrow saturated layer around 5 kft at around
-14C. This layer is generating the flurries that are falling into a
fairly dry layer underneath. That same RUC sounding indicates the
layer could stick around a little longer than in the previous
forecast so have extended the timing for flurries to at least 09Z.
Otherwise, the rest of the forecast is on track for lows in the
lower 20s tonight.
.SHORT TERM (Now through Friday Night)...
Issued at 300 PM EST Thu Nov 13 2014
We`ll continue to see flurry activity across the region late this
afternoon and evening as a cold Arctic airmass continues to settle
into the Midwest squeezing all available moisture out of the
atmosphere. Low clouds look to stick around through at least
midnight and then begin to thin from west to east during the
pre-dawn hours. This being the case, we could see a late night drop
off in temps as those clouds become scattered in nature. This
should result in low temps in the lower 20s tonight with a few upper
teens possible in sheltered areas.
Expect partly cloudy skies Friday as sfc high pressure settles into
the region becoming centered over the Ohio Valley Fri night. This
will result in high temps Friday in the mid 30s with low temps
Friday night bottoming out in the upper teens and lower 20s. Ideal
rad cooling conditions will exist for Friday night, so wouldn`t be
surprised to see some mid teens for lows.
.LONG TERM (Saturday through Thursday)...
Issued at 330 AM EST Thu Nov 13 2014
...Some Snow Accumulations Possible Sunday into Monday...
The main forecast challenge will be snow chances this weekend into
Monday.
The First Snow Chance...
Our first chance at a light snow will come Sat night into Sun
morning as a shortwave upper level trough pushes through the upper
Midwest and a weak frontal boundary attempts to organize near the TN
Valley. These two features never really look to become well phased
so it looks like we`ll remain in between systems to our north and
south Sat night into Sun morning. A weak plume of moisture over our
region looks to result in some light rain or rain/snow mix changing
over to all light snow sat night with maximum accumulations around a
half inch. Temps will warm into the upper 30s to around 40 Sun
afternoon causing any remaining precip to change over to light rain
and causing any light snow accums to melt.
The Second Snow Chance...
A better chance for snow over the region will arrive for Sun night
into Monday as a shortwave upper trough ejects out of the SW CONUS.
This wave will strengthen the weak sfc boundary located to our south
and pull up plentiful Gulf moisture into the Ohio Valley. As
typical with these overrunning precip events, a number of model
solns exists, each with differing depictions of storm track, warm
nose strength, and depth of the shallow cold air mass close
to the sfc. The 12Z runs from today still mostly put portions of
central KY under a threat for accumulating snows Sun night into Mon
morning. The ECMWF soln is farthest NW and would result in a threat
for accumulating snow over southern Indiana as well. The 12Z op GFS
would indicate a farther SE track shifting the main snow threat to
south central and east central KY. Also new with this model run are
more robust QPF fields from the GEM and ECMWF. This being said,
feel that a solid 1-3 inches of snowfall will be possible across a
portion of the Ohio Valley Sun night into Mon morning. Potentially
higher amounts of snowfall would be possible if the more robust QPF
fields pan out. For our latest thinking on best area for
accumulating snow and some preliminary snowfall amounts, see
weather.gov/lmk. The Monday morning commute has the potential to be
negatively impacted by this snowfall.
The Rest of the Week...
The rest of the week looks unseasonably cold with highs limited to
the 30s through Wed...potentially colder if snow accums can be
achieved Sun night/Mon morning. Low temps will be quite chilly in
the teens for mid week.
&&
.AVIATION (06Z TAF Update)...
Updated at 1205 AM EST Fri Nov 14 2014
Stratus shield that has covered the Ohio Valley the last couple days
is finally showing some breaks during the evening hours. Where there
is cloud, we have seen intermittent very light snow, but not really
enough to call it flurries nor enough to show up in observations.
Will carry VFR ceilings across the board through the night. Can`t
rule out a brief drop into high-end MVFR, but sufficiently low
clouds haven`t stuck around long enough in any location to develop a
ceiling.
Will once again go out on a limb and show the clouds scattering out
early to mid-morning as the nearly saturated layer around 4000 ft
AGL becomes shallower. However, we could see ceilings hold in until
early afternoon when the 850mb thermal trof finally starts to lift
out. Will keep scattered strato-cu until sunset, when daytime
heating is lost.
NW winds less than 10 kt through the day, then light and variable
after dark.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Update.........RJS
Short Term.....AMS
Long Term......EER/AMS
Aviation.......RAS
AREA FORECAST DISCUSSION
NWS GRAY ME
110 AM EST FRI NOV 14 2014
.SYNOPSIS...
LOW PRESSURE WILL OFF THE MID ATLANTIC COAST WILL MOVE
NORTHEASTWARD TONIGHT. THE LOW IS EXPECTED TO MOVE INTO THE
CANADIAN MARITIMES FRIDAY. HIGH PRESSURE WILL MOVE IN FOR THE
WEEKEND. LOW PRESSURE WILL MOVE INTO THE AREA MONDAY AND TUESDAY
BRINGING RAIN AND SNOW.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
1 AM UPDATE...LITTLE CHANGE TO THE GOING FORECAST. HAVE BLENDED
FORECAST WITH LATEST HRRR TO ALLOW FOR SHARPER POP TIMING.
SNOW IS STICKING TO GRASSY SURFACES MOST AREAS NOW...AND MAY BEGIN
TO STICK TO SECONDARY ROADS SHORTLY.
935PM UPDATE: ATTM LIGHT SNOW HAD SPREAD ACROSS NH AND WESTERN
AND SOUTHERN MAINE AS SCHEDULED. A FEW AREAS OVER SRN MAINE
STARTED AS RAIN OR A MIX. THE CURRENT FORECAST LOOKS GOOD WITH
ONLY MINOR TWEAKS.
PREV DISC:
MAIN CONCERN FOR THIS FORECAST REVOLVES AROUND DEVELOPING FRONTAL
WAVE OVER THE MID ATLANTIC. THIS FEATURE WILL FEED OFF THE FRESHLY
REINFORCED BAROCLINIC ZONE OFF THE COAST...WITH SFC LOW PRES
EXPECTED TO RAPIDLY DEVELOP AS IT PASSES CAPE COD. IN GENERAL
EXPECT A 2 TO 3 INCH SNWFL FOR COASTAL AREAS TO THE
FOOTHILLS...WITH ISOLATED AMOUNTS TO 4 INCHES POSSIBLE.
THE FORECAST IS A DIFFICULT ONE...WITH MIXED SIGNALS IN THE MODEL
GUIDANCE. ONE THING THAT IS CONSISTENT AMONG VARIOUS PIECES OF
GUIDANCE IS QPF. NWP HAS ABOUT 0.30 INCHES LIQUID JUST INLAND FROM
THE COAST...DROPPING TO ABOUT 0.20 INCHES AT THE FOOTHILLS. THIS
SUPPORTS A 2 TO 3 INCH SNWFL NICELY...AND DEPENDING ON INTENSITY
AND RATIOS UP TO 4.
A COUPLE CAUTION FLAGS ARE NOTED THOUGH. ONE IS THAT ISENTROPIC
FORCING IS WEAK. WINDS ARE GENERALLY PARALLEL TO PRES SURFACES
UNTIL YOU GET WELL OUT TO SEA. THIS WILL MEAN VERY LITTLE PCPN
FROM WAA PROCESSES. ANOTHER IS THAT TO THE NW SOME DRY AIR TRIES
TO CREEP INTO THE COLUMN. AS LIFT IS DISPLACED HIGHER UP IN THE
ATMOSPHERE ON THE COLD SIDE OF THE SYSTEM...THE GENERATION OF PCPN
MAY BE POOR OR NONEXISTENT. FOR THESE REASON EXPECT THAT THE WRN
EDGE TO SNWFL MAY BE SHARPER THAN THIS CURRENT FORECAST.
THAT BEING SAID...THERE ARE PLENTY OF POSITIVES FOR SNWFL AS WELL.
MID LEVELS WILL BE DEEPENING QUICKLY AROUND 12Z...AND AS THESE
CENTERS CLOSE OFF ENHANCED FRONTOGENESIS CAN BE EXPECTED ON THE
COLD SIDE. THIS IS PRIMARY MECHANISM FOR FRONTOGENESIS IN THIS
SYSTEM...AS STATED EARLIER WAA WILL BE WEAK. CROSS SECTION
ANALYSIS THRU KPWM PAINTS A FAVORABLE PICTURE TOO. AROUND 600 MB
THERE IS AN AREA OF -EPV ON ALL MODEL GUIDANCE...SHOWING THAT SOME
INSTABILITY ALOFT IS LIKELY. BENEATH THIS FEATURE...THE INCREASING
FRONTOGENESIS WILL PROVIDE AT LEAST MODEST LIFT THRU A SATURATED
SN GROWTH ZONE. THE COMBINATION OF WHICH IS FAVORABLE FOR BANDED
SNWFL STRUCTURES. SOUNDING ANALYSIS OF THE NAM FORECASTS SHOW A
POTENTIAL INTERESTING FEATURE TO BE CONCERNED WITH. ABOVE 600 MB
THE LAST SEVERAL NAM RUNS HAVE FEATURED A MAUL...OR MOIST
ABSOLUTELY UNSTABLE LAYER. IF LIFT CAN TAP THIS...WHICH IS LIKELY
WHERE MODELS ARE PLACING THE GREATEST -EPV...SNWFL RATES COULD BE
AT LEAST BRIEFLY INTENSE. FOR THIS REASON THE ISOLATED AMOUNT
AROUND 4 INCHES WAS INCLUDED.
FINALLY...GIVEN THAT MOST OF THE SNWFL IS EXPECTED TO OCCUR AFTER
09Z AND BEFORE 15Z...I ANTICIPATE THAT THERE WILL BE PROBLEMS
AROUND THE MORNING COMMUTE. FOR MANY OF THESE AREAS IT WILL BE THE
FIRST ACCUMULATING SNWFL GREATER THAN 1 INCH. THIS YEAR AFTER
YEAR IS SHOWN TO CAUSE TRAVEL ISSUES. SO I HAVE ISSUED A WINTER WX
ADVISORY FOR COASTAL AND COASTAL PLAIN ZONES HIGHLIGHTING THAT
MORNING COMMUTE IMPACT.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/...
SNWFL WILL BE COMING TO AN END RATHER QUICKLY FROM W TO E MID
MORNING FRI. TROF AXIS ALOFT HOWEVER WON/T CROSS THE AREA UNTIL
AFTERNOON. LINGERING MOISTURE AND INSTABILITY WITH THIS FEATURE
SHOULD ALLOW FOR AT LEAST SOME SCT SHSN...ESPECIALLY FOR THE
HIGHER TERRAIN. WHILE NOT EXPECTED FULL BLOWN ARCTIC SQUALLS...THE
BTV SNOW SQUALL PARAMETER I THINK IS DOING A GOOD JOB OF
HIGHLIGHTING THAT INSTABILITY.
SHOULD SEE ENOUGH DOWNSLOPING TO MITIGATE THE CAA OCCURRING ACROSS
THE CWFA. HIGH TEMPS WILL BE BELOW NORMAL...BUT NOT DRASTICALLY
SO. SFC HIGH PRES WILL STILL BE BUILDING IN FRI NIGHT...SO FEEL
THAT MOS GUIDANCE IS RUSHING THE COLDER TEMPS FOR THAT NEXT
MORNING. WENT ABOVE THE MAV/MET FOR MIN TEMPS.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
THE MODELS ARE IN GENERAL AGREEMENT ON THE LONG WAVE PATTERN WELL
INTO NEXT WEEK. THE WESTERN RIDGE/EASTERN TROUGH PATTERN
ADVERTISED BY THE MODELS WILL PROVIDE BELOW AVERAGE TEMPERATURES
THROUGH THE EXTENDED PERIOD. WE BEGIN THE PERIOD WITH WEAK
RIDGING SURFACE AND ALOFT FOR A FAIR BUT COLD DAY ON SATURDAY.
THE RIDGE SLIDES OFFSHORE FOR SUNDAY WITH A SOMEWHAT MILDER RETURN
FLOW...AND A BROAD SOUTHWEST FLOW ALOFT AS WE WAIT FOR THE UPPER
TROUGH TO RELOAD. WARM AIR ADVECTION WILL PRODUCE CLOUDS ALONG
WITH THE CHANCE FOR A FEW RAIN OR SNOW SHOWERS DEPENDENT LARGELY
ON BOUNDARY LAYER TEMPERATURES. BY MONDAY...THE TROUGH HAS
RELOADED WITH LEADING IMPULSE GIVING RISE TO AN ASSOCIATED SURFACE
LOW THAT RIDES NORTHEAST ALONG THE COAST. IT SHOULD BE NOTED THAT
THE MODEL TREND OVER THE PAST DAY HAS BEEN SLOWER...WEAKER...COLDER...
AND FURTHER OFFSHORE WITH THIS DISTURBANCE. AT THIS POINT...PRECIPITATION
LOOKS LIKE A RAIN SNOW MIX...WITH BEST CHANCE FOR ANY ACCUMULATING
SNOW INLAND. IN THE WAKE OF THIS SYSTEM...ANOTHER COLD FRONT AND
EVEN COLDER AIR WILL ARRIVE FOR TUESDAY AND THE MIDWEEK PERIOD.
THE WEST-SOUTHWEST TRAJECTORY OFF OF LAKE ONTARIO SHOULD SPREAD
LAKE EFFECT PLUME INTO WESTERN AND NORTHERN SECTIONS OF THE
FORECAST AREA LATE TUESDAY NIGHT AND WEDNESDAY WITH CLOUDS AND A
FEW SNOW SHOWERS LIKELY.
&&
.AVIATION /03Z FRIDAY THROUGH TUESDAY/...
SHORT TERM...APPROACHING TROF OF LOW PRES WILL BRING SN OR RASN
MIX CHANGING OVER TO SNWFL FOR ALL TERMINALS BETWEEN 04-08Z.
EXPECT IFR CONDITIONS ESPECIALLY CENTERED AROUND 09Z...FOR
TERMINALS NEAR THE COAST...KPSM...KPWM...KAUG...AND KRKD. BETWEEN
12-15Z CONDITIONS WILL IMPROVE TO MVFR AND THEN VFR QUICKLY AS
HIGH PRES BUILDS IN. SOME GUSTY WNWLY WINDS ARE POSSIBLE FRI
AFTERNOON.
LONG TERM...
SUN...SCT MVFR PSBL IN RAIN OR SNOW SHOWERS.
MON PM - TUE AM AREAS OF IFR IN RAIN AND SNOW.
&&
.MARINE...
SHORT TERM...BEHIND SFC TROF PASSAGE FRI...WINDS WILL GUST TO NEAR
25 KTS. A SCA MAY BE NEEDED FOR FRI AFTERNOON AND EVENING.
LONG TERM...
SUN PM - MON AM...SMALL CRAFT WINDS AND SEAS ARE POSSIBLE.
TUE PM - WED AM SMALL CRAFT WINDS AND SEAS ARE POSSIBLE.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...WINTER WEATHER ADVISORY UNTIL 8 AM EST FRIDAY FOR MEZ018>028.
NH...WINTER WEATHER ADVISORY UNTIL 8 AM EST FRIDAY FOR NHZ010-013.
MARINE...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
621 PM CST SAT NOV 15 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 351 PM CST SAT NOV 15 2014
STEADY LIGHT SNOW HAS ENGULFED SOUTHERN MN IN LIGHT SNOW THROUGH THE
DAY...WITH THE HEAVIEST BAND SETTING UP ALONG THE IOWA BORDER AS
EXPECTED. FOR THE REMAINDER OF THE AFTERNOON...WE`RE EXPECTING MOST
OF THE SNOW IN SOUTHERN MN TO WEAKEN AS FORCING WANES...AND THE
F-GEN MAX SLIDES SOUTH INTO IOWA...AS FRONTOLYSIS TAKES OVER ACROSS
WEST CENTRAL THROUGH SOUTHERN MN. THIS TREND IS QUITE APPARENT ON
RADAR AND HAS BEEN HANDLED WELL BY THE HRRR FOR THE LAST SEVERAL
RUNS. SO...EXPECT A LULL FOR MUCH OF THE AFTERNOON AND THE EVENING.
ANOTHER DECENT SNOW BAND WILL DEVELOP LATER TONIGHT. IT WILL CROSS
THE MN/SD BORDER AROUND 6-7 PM AND CONTINUE EASTWARD...PRODUCING
LIGHT ACCUMULATIONS ACROSS THE SOUTHERN HALF OF THE STATE AND
THROUGH WEST CENTRAL WI. FOR THE TWIN CITIES...THIS BAND WILL
PRODUCE AN ADDITIONAL 0.5"-1" MAINLY FROM 9PM THROUGH 1AM.
CURRENTLY EXPECTING THE BACK EDGE OF THIS BAND TO CROSS THE MN/WI
LINE AT ABOUT 3AM...WITH LIGHT SNOW LINGERING UNTIL 5-6AM NEAR EAU
CLAIRE.
OVERNIGHT TEMPERATURES LAST NIGHT WERE A GOOD FIVE DEGREES COLDER
THAN EXPECTED OVER THE SOLID SNOW PACK. IN COLLABORATION WITH OTHER
OFFICES...WENT SLIGHTLY COOLER ACROSS THE WEST THAN MOST OF THE
GUIDANCE...BUT THE EASTERN CWA WILL RETAIN SOMEWHAT WARMER
TEMPERATURES UNDER CONSISTENT CLOUD COVER /AND LINGERING LIGHT
PRECIP OVERNIGHT/. BY TOMORROW MORNING...WINDS WILL HAVE TURNED
WESTERLY AND WILL INCREASE THROUGH THE DAY. STRONG CAA APPARENT AT
925H ON THE BACKSIDE OF THE WAVE WILL MAKE FOR A COLD SUNDAY. 925H
TEMPS AROUND -12C ACROSS MOST OF THE REGION WILL ONLY ALLOW SURFACE
TEMPS TO MIX INTO THE UPPER TEENS.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 351 PM CST SAT NOV 15 2014
THE WEEK AHEAD REMAINS EXTREMELY COLD FOR MID NOVEMBER WITH THREE
SURGES OF ARCTIC AIR FORECAST ACROSS THE UPPER MISSISSIPPI VALLEY.
THE FIRST IS SUNDAY NIGHT/MONDAY...THE SECOND TUESDAY NIGHT/WEDNESDAY
WITH THE THIRD ON THURSDAY. LOWS/HIGHS THROUGH THE PERIOD WILL
CONTINUE TO AVERAGE SOME 20 TO 30 DEGREES BELOW NORMAL. THE TREND
TODAY WAS TO CONTINUE LOWERING TEMPERATURES OVER THE BLENDED
GUIDANCE DUE TO A MORE EXPANSIVE SNOW PACK. THE ARCTIC SURGE THAT
OCCURS SUNDAY NIGHT/MONDAY OFFERS THE BEST CHANCE FOR SNOW
SHOWERS...ESPECIALLY ACROSS CENTRAL MINNESOTA AND WEST CENTRAL
WISCONSIN...WHERE A FLUFFY INCH OR TWO COULD OCCUR. THE OTHER TWO
ARCTIC SURGES HAVE THE BETTER MOISTURE AND FORCING TO THE NORTHEAST
OF OUR FORECAST AREA RESULTING IN LESS CHANCES FOR SNOW FOR US.
THE MAIN CONCERN IN THE LONG TERM IS THE BLOWING SNOW POTENTIAL IN
THE MINNESOTA RIVER VALLEY SUNDAY NIGHT AND MONDAY. THE CONCERN
FOR BLIZZARD CONDITIONS DEVELOPING ON MONDAY HAS WANED A BIT TODAY
AS ALL OF THE DETERMINISTIC MODELS HAVE DECREASED THE SURFACE
PRESSURE GRADIENT ACROSS THE MN FORECAST AREA FROM 10 MB TO 8 MB IN
THE PAST 24 HOURS. THIS HAS LOWERED WIND SPEED FORECASTS A LITTLE
ON MONDAY FROM KRWF TO KFRM. IN ADDITION...SNOWFALL ACCUMULATION
SO FAR TODAY HAS BEEN HIGHEST IN EASTERN SOUTH DAKOTA AND FAR
SOUTHWEST MINNESOTA (OUTSIDE OF OUR FORECAST AREA) WHERE 3 TO 5
INCHES HAVE BEEN COMMON. SNOWFALL IN OUR AREA OF WEST CENTRAL
THROUGH SOUTH CENTRAL MINNESOTA HAS BEEN MORE IN THE 1 TO 3 INCH
RANGE.
BUFKIT PROFILES FROM BOTH THE NAM AND GFS SHOW THAT THE BEST LOW
LEVEL LAPSE RATES AND HIGHEST TOP OF THE CHANNEL MOMENTUM TRANSFER
DON/T OCCUR UNTIL LATE MONDAY MORNING AND AFTERNOON FROM WEST
CENTRAL THROUGH SOUTH CENTRAL MINNESOTA. ALTHOUGH AREAS OF
BLOWING SNOW WILL BEGIN ACROSS WEST CENTRAL THROUGH SOUTH CENTRAL
MINNESOTA SUNDAY NIGHT IN THE WAKE OF THE ARCTIC FRONT...THERE
ARE STILL SOME INDICATIONS THAT SUSTAINED WIND SPEEDS COULD REACH
25 MPH FROM KRWF TO KFRM MONDAY AFTERNOON WITH GUSTS HITTING 40
MPH. THIS COULD RESULT IN NEAR BLIZZARD CONDITIONS FOR A COUPLE OF
HOURS IN THESE AREAS. COMPLICATING MATTERS IS THE THREAT FOR SNOW
SHOWERS ALONG WITH THE SATURATED LOW LEVEL CONDITIONS REMAINING IN
THE DENDRITIC GROWTH ZONE.
AT THIS POINT...DIDN/T HAVE ENOUGH CONFIDENCE TO ISSUE A BLIZZARD
WATCH FOR MONDAY FROM YELLOW MEDICINE AND RENVILLE COUNTIES ON
SOUTHEAST TO MARTIN AND FARIBAULT WITH THE PRESSURE GRADIENT
WEAKENING SOME AND THE HIGHER SNOW TOTALS TODAY TO OUR WEST. THERE
IS STILL PLENTY OF TIME LATER TONIGHT TO ISSUE A WATCH IF WIND
CONDITIONS CHANGE WITH THE 00Z MODEL RUNS. OTHERWISE...A WINTER
WEATHER ADVISORY FOR BLOWING SNOW WILL LIKELY BE ISSUED ON SUNDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 611 PM CST SAT NOV 15 2014
LIGHT SNOW WILL CONTINUE ACROSS MN/WI FOR THE REMAINDER OF THE
EVENING AND SLOWLY COME TO AN END FROM WEST T0 EAST BETWEEN 03Z-06Z
IN MN...AND 06Z-09Z IN WI. HIGH CONFIDENCE IN MVFR/IFR VISIBILITY
AND MVFR CEILINGS UNTIL THE SNOW MOVES OUT.
KMSP...
WHAT YOU SEE IS WHAT YOU GET FOR THE NEXT 6 HOURS OR SO...VIS
RANGING BETWEEN 1 1/2SM AND 5SM...DEPENDING ON WHEN THE POCKETS OF
HEAVIER SNOW MOVE THROUGH. SHOULD PRIMARILY BE 3-4SM WITH LIGHT
SNOW. SNOW MOVES OUT AROUND 06Z. CEILINGS WILL FOLLOW SOON AFTER.
/OUTLOOK FOR KMSP/
MON...SLIGHT CHC -SN WITH IFR/MVFR CIGS. WINDS NW 15-20 G 25 KTS.
TUE...VFR. WINDS W 10-15 KTS.
WED...VFR. WINDS NW 10-15 KTS G 20 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR
MNZ073>076-082>085-091>093.
WI...NONE.
&&
$$
SHORT TERM...SPD
LONG TERM...RAH
AVIATION...CLF
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
611 PM CST Sat Nov 15 2014
.SHORT TERM: (Through Late Tonight)
Issued at 347 PM CST Sat Nov 15 2014
Shortwave exiting the eastern Plains into the Mississippi Valley is
producing a little bit of light snow and flurry activity across the
CWFA today. Looks like the best snowfall has moved north of our
CWFA across extreme northeast Missouri and southeast Iowa into west
central Illinois. The broad scale mid level lift associated with
the shortwave is lifting quickly northeast according to the RAP and
NAM. Will likely see a little bit of lingering snowfall up there
this evening, but any accumulations this evening should be well
under an inch.
Further south, HRRR and RAP have been very insistent that there will
be a frontogenetical band of snow this evening somewhere between
I-44 and I-70. The band will move northeast affecting parts of the
STL metro area with some light snow. Simulated reflectivity off the
4km NCEP and NSSL WRF models also show this, and the operational NAM
and GFS bear this out with a few hundredths of QPF. Latest radar
mosaic shows a band of snow developing west central Missouri
now...so this looks likely to happen. Have a band of likely PoPs
this evening in to account for this snow, stretching across central
Missouri into southwest Illinois to account for this.
Carney
.LONG TERM: (Sunday through Next Saturday)
Issued at 347 PM CST Sat Nov 15 2014
(Sunday thru Tuesday)
This period will continue to feature much below normal temps and
another shot at accumulating snow. Models have come into better
agreement with the system for Sunday/Sunday night. All guidance has
shifted the forcing and subsequently the precip shield further
north. Timing should be similar to today`s event. Precip is
expected to begin across cntrl and SE MO around noon and then spread
east thru the rest of the CWA during the aftn and then clear from W
to E during the evng and be but a memory by midnight. The main
p-type should be snow with temps aloft plenty cold enough to support
ice crystal formation but...air temps above freezing at the
beginning of the event may cause a rain/snow mix at the onset of the
precip. I think the mix won`t last long as temps should wet bulb
shortly after the precip begins. This will likely lead to a
non-diurnal temp trend as temps fall across the sthrn CWA as the
precip progresses east. Accum rates may be limited early on in the
event for a variety of reasons beyond the warm air temps
including...ground temps will likely be above freezing, snowfall
rates may not be high enough and the aftn sun...even with the
diminished angle...will have an effect. Event total snowfall amounts
should be 1-2 inches along and south of I70. There may be a band of
slightly enhanced snowfall along the I44 corridor that may reach
upwards of 3 inches but not confident on band placement to include
in the fcst attm. The system quickly lifts east after midnight.
Monday looks like a raw day with potentially steady or slowly
falling temps and a stiff NW wind as a 1030mb sfc high builds in.
850 temps fall from the negative single digits at 6Z Monday to the
negative mid teens to near -20 by Monday evening. There is also an
impressive short wave dropping down in the NW flow on Monday that
should instigate at least occnl flurries with the possibility of
actual snow showers...as was the case this past Thursday. Models
hint at patchy QPF which would equate to a few tenths of an inch of
snow...but will let later shifts asses that threat as it is still 2
days away. Tuesday should be the last truly cold day as the sfc
ridge passes to the south.
(Tuesday night thru Friday)
The upper flow flattens thru the end of the week which will allow
for a moderating trend. Winds will swing around to the south on the
backside of the high Tuesday night. 850 temps near 0 and a Srly wind
will boost temps to the upper 30s north to the upper 40s south
on Wednesday. The next short waves pushes a cold front thru late in
the day on Wednesday causing temps on Thursday and Friday to be a
touch cooler. This front appears to be dry at this time. Models
guidance diverges after this feature with the GFS building a strong
sfc ridge into the Midwest for the end of the week while the ECMWF
has another short wave and an attendant weak sfc low that tracks
across sthrn MO/IL Thursday/Thursday night.
Both models suggest another storm system for either the wknd and/or
early next week as the next main short wave approaches in the mean
flow.
2%
&&
.AVIATION: (For the 00z TAFs through 00z Sunday Evening)
Issued at 611 PM CST Sat Nov 15 2014
Initial shortwave exiting region, however secondary shortwave over
west central MO tracking to the east northeast, so will continue
to see light snow/flurries for taf sites along I-70 corridor this
evening. So have mvfr cigs through 02z Sunday for KCOU and through
03z Sunday for metro area tafs. Another stronger shortwave to
slide through region late Sunday morning through early Sunday
evening with mvfr conditions once again for taf sites along I-70
corridor with heaviest snow just south of these sites. Southeast
to south winds to become light and variable overnight, then veer
to the west as stronger shortwave moves through on Sunday.
Specifics for KSTL:
Initial shortwave exiting region, however secondary shortwave over
west central MO tracking to the east northeast, so will continue
to see light snow/flurries for metro area this evening. So have mvfr
cigs through 03z Sunday KSTL. Another stronger shortwave to slide
through region late Sunday morning through early Sunday evening
with mvfr conditions once again for metro area with heaviest snow
just south of metro area. Southeast to south winds to become
light and variable by 03z Sunday, then veer to the west as stronger
shortwave moves through around 17z Sunday. Snow to taper off after
00z Monday with cigs lifting to vfr.
Byrd
&&
.CLIMATE:
Issued at 748 PM CST Thu Nov 13 2014
The following are record low maximums and record low minimums for
each of the next 5 days, which corresponds to the expected length
of the current cold spell and record snowfall for St. Louis and
Columbia for Saturday and Sunday when the area is expecting the
first widespread accumulating snowfall of the season.
Date: 11/15 11/16 11/17 11/18
St. Louis
Low High: 29/1940 29/1997 17/1880 25/1880
Low: 11/1940 13/1959 6/1959 14/1932
Snowfall: 0.1/1997 1.0/1951
Columbia
Low High: 28/1940 30/1932 23/1959 27/1903
Low: 6/1940 8/1959 4/1959 8/1891
Snowfall: 4.8/1932 0.1/1989
Quincy
Low High: 29/1940 28/1997 19/1959 24/1903
Low: 7/1940 4/1959 3/1959 7/1903
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
542 PM CST Sat Nov 15 2014
...Updated for Aviation...
.DISCUSSION...
Issued at 418 PM CST SAT NOV 15 2014
Tonight - Sunday:
As today`s system which generated 2-4 inches of snow over the far
northern counties exits the region our attention turns to three
secondary areas of snow. An area of snow over Nebraska is tied to a
shortwave trough moving east through western SD/NE. The trailing
band of enhanced clouds/snow is expected to drag through the CWA
overnight but only the far northwestern counties have a chance of
more than a dusting...maybe 1/2" to and inch. The expected band of
snow should diminish in intensity overnight but most areas will see
at least intermittent flurries.
The second region of snow is a result of the seeder-feeder mechanism
as noted by the broken area of enhanced mid clouds which have formed
from east central KS into west central MO. There likely is a weak
mid-level vorticity max tied to this region of cloud and the NAM h7
prog seems to hint on this. Only the short-range HRRR has picked up
on this. Could get a quick half inch of snow across the far southern
CWA during the late afternoon/early evening hours before the feature
weakens as it quickly heads east.
The third area of snow is expected to form over the CO Rockies
tonight and rapidly expand as a narrow band in response to the left
front quad of an upper level jet streak races through the Central
Rockies and into KS/OK Sunday morning. Operational models do depict
one or two vorticity lobes tracking into the region within an
overall area of ascent. At this time the northern edge of the
expected snow band could skirt across our far southern counties so
have added chance PoPs to this area.
Otherwise, until the primary upper trough passes through late on
Sunday am expecting mostly cloudy skies for most of the CWA. This
will mute the diurnal temperature range.
Monday - Tuesday:
Much below average temperatures will continue during this period
with the potential for a record low max temperature on Monday and
record setting lows Tuesday morning. Another upper trough will dig
southward Sunday night and Monday and result in falling mid/upper
level heights and enhance the flow of Arctic air southward from the
Canadian Plains to central U.S. Another surge of this air will move
in during this period. Steep lapse rates below 750mb and a moist
layer residing within the boundary layer suggests a good chance for
instability snow showers or flurries Monday afternoon.
Wednesday - Saturday:
This should be a dry period with a continuation of the unseasonably
cold regime. Cyclonic/northwest flow aloft will continue featuring
the potential for weak embedded shortwaves to pass through. However,
the airmass will be quite dry so it should remain dry. A slight
moderation in temperatures are expected but they will remain about
15 degrees below average.
A particularly cold air mass will swing into the Central Plains
Monday into Tuesday. This will result in the coldest temperatures we
have seen this fall with both Monday`s high temperatures and Tuesday
morning`s low temperatures possibly setting new records. Here is a
quick look at just some of those threatened temperature records.
&&
.AVIATION...(For the 00Z TAFS through 00Z Sunday Evening)
Issued at 535 PM CST SAT NOV 15 2014
Very light snow along and north of a line from KIXD through just
south of Trenton Missour which will continue moving east northeast.
This area is not lowering cigs/vsby except at KIXD where vsby went
down to MVFR. Expect the terminals to have this -SN for the next
several hours to around 08 UTC...then some lower cigs to around
OVC025 until around 15 UTC tomorrow morning.
&&
.CLIMATE...
Issued at 418 PM CST SAT NOV 15 2014
Monday
November 17th Current Record Low Forecast High Monday
Record Low Highs High Afternoon
--------------------------------------------------------------------
Kansas City 24 in 1891 22
St. Joseph 26 in 1951 22
Tuesday
November 18th Current Record Low Forecast Low Tuesday
Record Lows Morning
--------------------------------------------------------------------
Kansas City 14 in 1903 7
St. Joseph 16 in 1989 5
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
MO...WINTER WEATHER ADVISORY until Midnight CST tonight FOR
MOZ001>003-011.
&&
$$
DISCUSSION...MJ
AVIATION...Adolphson
CLIMATE...Cutter
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
953 PM CST SAT NOV 15 2014
.UPDATE...
ISSUED AT 904 PM CST SAT NOV 15 2014
THE FRONT CONTS TO MAKE STEADY PROGRESS TO THE SOUTHEAST THROUGH
THE CWA THIS EVNG. AREAS OF MAINLY LIGHT SNOW HAVE CONTD ALONG AND
AHEAD OF THE COLD FRONT...AND THIS IS EXPECTED TO CONT TO TRACK
TO THE EAST THROUGH THE REST OF THE EVNG AS THE COLD FRONT MOVS E
AND THE UPPER LEVEL FORCING EXITS. SFC 3-HR PRES RISES OF 2-3 MB
ARE DIRECTLY BEHIND THE FRONT AND ARE ALLOWING FOR GUSTY NORTHWEST
WINDS. THIS MAY ALLOW FOR SOME PATCHY BLOWING SNOW IN OPEN
AREAS...BUT UPSTREAM OBSERVATIONS INDICATE LITTLE IN THE WAY OF
VISIBILITY RESTRICTIONS. THUS HAVE CANCELLED THE WNTR WX ADVRY FOR
THE NW CWA AND AS THE LAST OF THE SN EXITS THE CNTRL/ERN CWA WE
WILL DO THE SAME THERE BUT KEEP SOME MENTION OF PATCHY BLOWING
SNOW GOING. OTHERWISE OTHER THAN SOME MINOR TIMING CHANGES
ONGOING FORECAST WAS IN GOOD SHAPE WITH NO SIGNIFICANT CHANGES
PLANNED.
&&
.SHORT TERM...(TONIGHT THROUGH TUESDAY)
ISSUED AT 331 PM CST SAT NOV 15 2014
ENDING SNOW TONIGHT...THEN COLD TEMPERATURES THE NEXT FEW DAYS...ARE
THE PRIMARY FORECAST CONCERNS.
FIRST ROUND OF SNOW TIED TO SOUTHERN SHORTWAVE/WARM ADVECTION
PATTERN MOVED EAST/NORTHEAST OF THE CWA BY EARLY AFTERNOON. THIS
AREA DROPPED AN INCH OR TWO OF SNOW ACROSS THE SOUTHERN HALF OF
THE CWA. ANOTHER AREA OF SNOW WAS ENTERED THE WESTERN PART OF
NORTHEAST NEBRASKA EARLY IN THE AFTERNOON. THIS WAS TIED TO
STRONGER UPPER LOW/TROUGH SWINGING THROUGH WESTERN SOUTH DAKOTA.
75KT MID LEVEL JET WAS ROUNDING BASE OF THIS FEATURE...INCREASING
LIFT IN NORTHEAST WHERE SECOND ROUND OF SNOW WAS FALLING THIS
AFTERNOON. CHARACTER OF RADAR RETURNS SUGGEST THIS AREA WILL
PRODUCE LIGHT SNOW FOR THE MOST PART...WITH A FEW ROUNDS OF
MODERATE SNOW FROM TIME TO TIME. PROGRESSIVE NATURE ALSO SUGGESTS
MESOSCALE MODEL FORECASTS FROM HRRR AND RAP IN SHOWING SNOW
AFFECTING MAINLY THE NORTHERN HALF OF THE CWA AND WINDING DOWN BY
MIDNIGHT STILL LOOKS GOOD. ADDITIONAL AMOUNTS OF 1 TO 2 INCHES ARE
POSSIBLE IN THE NORTHERN TWO-THIRDS OF THE CWA TAPERING TO LESS
THAN AN INCH TOWARD THE KANSAS BORDER.
BACK EDGE OF SNOW WILL ALSO COINCIDE WITH COLD FRONT SWEEPING ACROSS
THE PLAINS. FRONT WILL PASS NORFOLK BY 9 PM AND BE APPROACHING OMAHA
BY MIDNIGHT. GUSTY NORTHWEST WINDS OF 15 TO 25 MPH SHOULD
FOLLOW...CAUSING A LITTLE BLOWING AND DRIFTING OF SNOW OVERNIGHT
BEFORE WINDS BEGIN TO SUBSIDE SOME ON SUNDAY. CLEARING SKIES AFTER
MIDNIGHT...COLD AIRMASS AND FRESH SNOW COVER WILL LEAD TO COLD
TEMPERATURES BY MORNING...WITH WINDS ONLY THING KEEPING LOWS FROM
BOTTOMING OUT. SINGLE DIGITS ARE FORECAST MOST EVERYWHERE.
SUNDAY WILL BRING SUNSHINE AND SOUTHWEST FLOW AHEAD OF A REINFORCING
COLD FRONT SLATED TO ARRIVE INTO NORTHEAST NEBRASKA IN THE
AFTERNOON...THEN THROUGH THE REST OF THE AREA DURING THE EVENING.
SNOW COVER WILL KEEP TEMPS FROM REACHING MAXIMUM POTENTIAL SUNDAY
AFTERNOON...WITH LOWER 20S EXPECTED MOST AREAS. MORE GUSTY NORTHWEST
WINDS WILL ACCOMPANY COLD FRONT AND SHOULD CONTINUE ALL NIGHT.
EXTREMELY COLD AIRMASS FOLLOWS THE FRONT WITH MODELS SHOWING -20
850 TEMPERATURES INTO OUR NORTHERN CWA BY 12Z MONDAY. THIS WILL
TRANSLATE TO LOWS AGAIN IN THE SINGLE DIGITS WITH HIGHS REBOUNDING
ONLY BACK INTO THE TEENS MONDAY AFTERNOON. WIND CHILLS MONDAY
MORNING WILL LIKELY FALL TO 15 BELOW OR COLDER FOR MUCH OF THE
NORTHERN HALF OF THE CWA.
DECREASING WINDS AND CLEARING SKIES SUGGEST TUESDAY MORNING MAY BE
THE COLDEST OF THIS RECENT COLD SPELL. LOWS NEAR ZERO ARE LIKELY
ACROSS ALL OF EASTERN NEBRASKA AND SOUTHWEST IOWA...WITH SUB-ZERO
TEMPS NEARLY A CERTAINTY IN OUR NORTH. SOUTHWEST FLOW RETURNS FOR
TUESDAY...HELPING TO WARM TEMPS BACK INTO THE MID 20S IN THE
AFTERNOON.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 331 PM CST SAT NOV 15 2014
SLOWLY MODERATING TEMPERATURES APPEAR TO BE THE MAIN STORY IN THE
LONGER TERM PERIOD.
ANOTHER SHORTWAVE IS SHOWN BY GFS/ECMWF SLAMMING THROUGH MINNESOTA
AND IOWA TUESDAY NIGHT...BRINGING ANOTHER SHOT OF COLDER AIR INTO
THE PLAINS THROUGH WEDNESDAY. HOWEVER THIS WILL NOT BE NEARLY AS
COLD AS EARLIER IN THE WEEK WITH HIGHS WEDNESDAY INTO THE 20S AND
LOWER 30S. MID LEVEL HEIGHTS BEGIN A SLOW RISE FOR THE REST OF THE
WEEK AS FLOW BECOMES MORE ZONAL BEHIND TUESDAY NIGHT SHORTWAVE.
ANOTHER SHOT OF SOMEWHAT COOLER AIR IS EXPECTED THURSDAY...BUT THAT
LOOKS SHORT-LIVED. HAVE HIGHS REBOUNDING BACK INTO THE 30S FRIDAY
AND SATURDAY. OTHERWISE A DRY FORECAST REMAINS INTACT.
&&
.AVIATION...(00Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 530 PM CST SAT NOV 15 2014
BAND OF HEAVIER SN WILL CONT TO MOV THROUGH KLNK/KOMA OVER THE
NEXT TWO HOURS AND THEN THE SN WILL TAPER TO FLURRIES THROUGH THE
EVENING. IFR CONDS ARE LIKELY OVER THE NEXT COUPLE OF HOURS AT
THESE SITES BEFORE WE CAN EXPECT MVFR CIGS THROUGH THE EARLY MRNG
BEFORE THINGS SCT OUT. SFC CDFNT IS MVG THROUGH KOFK ATTM...AND
WILL MOV THRU KOMA/KLNK ARND 04-06Z. WINDS WILL BECOME NORTHWEST
AT ALL 3 SITES WITH AT LEAST BRIEF GUSTY WINDS BEHIND THE
FRONT. VFR CONDITIONS ARE EXPECTED THROUGH THE DAY ON SUNDAY.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR NEZ015-
033-034-044-045-051>053-066>068.
IA...WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR IAZ043-
055-056-069-079-080-090-091.
&&
$$
UPDATE...BOUSTEAD
SHORT TERM...DERGAN
LONG TERM...DERGAN
AVIATION...
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
537 PM CST SAT NOV 15 2014
.SHORT TERM...(TONIGHT THROUGH TUESDAY)
ISSUED AT 331 PM CST SAT NOV 15 2014
ENDING SNOW TONIGHT...THEN COLD TEMPERATURES THE NEXT FEW DAYS...ARE
THE PRIMARY FORECAST CONCERNS.
FIRST ROUND OF SNOW TIED TO SOUTHERN SHORTWAVE/WARM ADVECTION
PATTERN MOVED EAST/NORTHEAST OF THE CWA BY EARLY AFTERNOON. THIS
AREA DROPPED AN INCH OR TWO OF SNOW ACROSS THE SOUTHERN HALF OF
THE CWA. ANOTHER AREA OF SNOW WAS ENTERED THE WESTERN PART OF
NORTHEAST NEBRASKA EARLY IN THE AFTERNOON. THIS WAS TIED TO
STRONGER UPPER LOW/TROUGH SWINGING THROUGH WESTERN SOUTH DAKOTA.
75KT MID LEVEL JET WAS ROUNDING BASE OF THIS FEATURE...INCREASING
LIFT IN NORTHEAST WHERE SECOND ROUND OF SNOW WAS FALLING THIS
AFTERNOON. CHARACTER OF RADAR RETURNS SUGGEST THIS AREA WILL
PRODUCE LIGHT SNOW FOR THE MOST PART...WITH A FEW ROUNDS OF
MODERATE SNOW FROM TIME TO TIME. PROGRESSIVE NATURE ALSO SUGGESTS
MESOSCALE MODEL FORECASTS FROM HRRR AND RAP IN SHOWING SNOW
AFFECTING MAINLY THE NORTHERN HALF OF THE CWA AND WINDING DOWN BY
MIDNIGHT STILL LOOKS GOOD. ADDITIONAL AMOUNTS OF 1 TO 2 INCHES ARE
POSSIBLE IN THE NORTHERN TWO-THIRDS OF THE CWA TAPERING TO LESS
THAN AN INCH TOWARD THE KANSAS BORDER.
BACK EDGE OF SNOW WILL ALSO COINCIDE WITH COLD FRONT SWEEPING ACROSS
THE PLAINS. FRONT WILL PASS NORFOLK BY 9 PM AND BE APPROACHING OMAHA
BY MIDNIGHT. GUSTY NORTHWEST WINDS OF 15 TO 25 MPH SHOULD
FOLLOW...CAUSING A LITTLE BLOWING AND DRIFTING OF SNOW OVERNIGHT
BEFORE WINDS BEGIN TO SUBSIDE SOME ON SUNDAY. CLEARING SKIES AFTER
MIDNIGHT...COLD AIRMASS AND FRESH SNOW COVER WILL LEAD TO COLD
TEMPERATURES BY MORNING...WITH WINDS ONLY THING KEEPING LOWS FROM
BOTTOMING OUT. SINGLE DIGITS ARE FORECAST MOST EVERYWHERE.
SUNDAY WILL BRING SUNSHINE AND SOUTHWEST FLOW AHEAD OF A REINFORCING
COLD FRONT SLATED TO ARRIVE INTO NORTHEAST NEBRASKA IN THE
AFTERNOON...THEN THROUGH THE REST OF THE AREA DURING THE EVENING.
SNOW COVER WILL KEEP TEMPS FROM REACHING MAXIMUM POTENTIAL SUNDAY
AFTERNOON...WITH LOWER 20S EXPECTED MOST AREAS. MORE GUSTY NORTHWEST
WINDS WILL ACCOMPANY COLD FRONT AND SHOULD CONTINUE ALL NIGHT.
EXTREMELY COLD AIRMASS FOLLOWS THE FRONT WITH MODELS SHOWING -20
850 TEMPERATURES INTO OUR NORTHERN CWA BY 12Z MONDAY. THIS WILL
TRANSLATE TO LOWS AGAIN IN THE SINGLE DIGITS WITH HIGHS REBOUNDING
ONLY BACK INTO THE TEENS MONDAY AFTERNOON. WIND CHILLS MONDAY
MORNING WILL LIKELY FALL TO 15 BELOW OR COLDER FOR MUCH OF THE
NORTHERN HALF OF THE CWA.
DECREASING WINDS AND CLEARING SKIES SUGGEST TUESDAY MORNING MAY BE
THE COLDEST OF THIS RECENT COLD SPELL. LOWS NEAR ZERO ARE LIKELY
ACROSS ALL OF EASTERN NEBRASKA AND SOUTHWEST IOWA...WITH SUB-ZERO
TEMPS NEARLY A CERTAINTY IN OUR NORTH. SOUTHWEST FLOW RETURNS FOR
TUESDAY...HELPING TO WARM TEMPS BACK INTO THE MID 20S IN THE
AFTERNOON.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 331 PM CST SAT NOV 15 2014
SLOWLY MODERATING TEMPERATURES APPEAR TO BE THE MAIN STORY IN THE
LONGER TERM PERIOD.
ANOTHER SHORTWAVE IS SHOWN BY GFS/ECMWF SLAMMING THROUGH MINNESOTA
AND IOWA TUESDAY NIGHT...BRINGING ANOTHER SHOT OF COLDER AIR INTO
THE PLAINS THROUGH WEDNESDAY. HOWEVER THIS WILL NOT BE NEARLY AS
COLD AS EARLIER IN THE WEEK WITH HIGHS WEDNESDAY INTO THE 20S AND
LOWER 30S. MID LEVEL HEIGHTS BEGIN A SLOW RISE FOR THE REST OF THE
WEEK AS FLOW BECOMES MORE ZONAL BEHIND TUESDAY NIGHT SHORTWAVE.
ANOTHER SHOT OF SOMEWHAT COOLER AIR IS EXPECTED THURSDAY...BUT THAT
LOOKS SHORT-LIVED. HAVE HIGHS REBOUNDING BACK INTO THE 30S FRIDAY
AND SATURDAY. OTHERWISE A DRY FORECAST REMAINS INTACT.
&&
.AVIATION...(00Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 530 PM CST SAT NOV 15 2014
BAND OF HEAVIER SN WILL CONT TO MOV THROUGH KLNK/KOMA OVER THE
NEXT TWO HOURS AND THEN THE SN WILL TAPER TO FLURRIES THROUGH THE
EVENING. IFR CONDS ARE LIKELY OVER THE NEXT COUPLE OF HOURS AT
THESE SITES BEFORE WE CAN EXPECT MVFR CIGS THROUGH THE EARLY MRNG
BEFORE THINGS SCT OUT. SFC CDFNT IS MVG THROUGH KOFK ATTM...AND
WILL MOV THRU KOMA/KLNK ARND 04-06Z. WINDS WILL BECOME NORTHWEST
AT ALL 3 SITES WITH AT LEAST BRIEF GUSTY WINDS BEHIND THE
FRONT. VFR CONDITIONS ARE EXPECTED THROUGH THE DAY ON SUNDAY.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR NEZ011-
012-015>018-030>034-042>045-050>053-065>068-078.
IA...WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR IAZ043-
055-056-069-079-080-090-091.
&&
$$
SHORT TERM...DERGAN
LONG TERM...DERGAN
AVIATION...
AREA FORECAST DISCUSSION
NWS RALEIGH NC
719 PM EST SAT NOV 15 2014
.SYNOPSIS...HIGH PRESSURE WILL GRADUALLY SHIFT OFFSHORE TONIGHT AND
SUNDAY. A DEVELOPING LOW PRESSURE SYSTEM ATTENDANT AN AMPLIFYING
UPPER LEVEL TROUGH WILL INTENSIFY IN VICINITY OF THE LOUISIANA GULF
COAST ON SUNDAY...THEN TRACK NORTHEAST ALONG THE SPINE OF THE
APPALACHIANS SUNDAY NIGHT INTO MONDAY. AN ASSOCIATED COLD FRONT WILL
SWEEP EASTWARD THROUGH THE CAROLINAS MONDAY AFTERNOON AND EVENING.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 300 PM SATURDAY...
TODAY: MODIFIED ARCTIC HIGH PRESSURE CENTERED OVER THE REGION WILL
ENSURE THAT DRY CONDITIONS AND LIGHT/VARIABLE WINDS PREVAIL THROUGH
TONIGHT. THE LOW-LEVEL CORE OF THE MODIFIED ARCTIC AIRMASS WAS
ANALYZED DIRECTLY OVER CENTRAL NC AND EASTERN VA THIS AFTERNOON
(18Z)...CHARACTERIZED BY 925 MB TEMPS IN VICINITY OF -2C. PWAT
VALUES BOTTOMED OUT AT A `FINGER-CRACKING` 0.14 INCHES ON THE GSO
RAOB 00Z YESTERDAY. 18Z MESOANALYSIS AND RAP DATA INDICATE MID/UPPER
LEVEL MOISTURE HAS STEADILY INCREASED SINCE 00Z...THOUGH LITTLE
EVIDENCE THEREOF (I.E. CIRRUS) CAN BE IDENTIFIED VIA SATELLITE
IMAGERY. GIVEN CLEAR SKIES AND MARGINAL LOW-LEVEL MODIFICATION IN
COMPARISON TO YESTERDAY...EXPECT HIGHS SIMILAR ALBEIT SLIGHTLY WARMER
THAN YESTERDAY...IN THE LOWER/MID 40S.
TONIGHT: MODIFIED ARCTIC HIGH PRESSURE CENTERED OVER THE MID-
ATLANTIC THIS EVENING WILL SHIFT OFFSHORE THE MID-ATLANTIC COAST
LATE TONIGHT...IN ADVANCE OF SHORTWAVE ENERGY TRACKING EASTWARD FROM
THE DAKOTAS TO THE UPPER GREAT LAKES. MEANWHILE...UPSTREAM PRECIP IS
EXPECTED TO BLOSSOM ACROSS THE LOWER MS RIVER VALLEY AFTER MIDNIGHT
AS SHORTWAVE ENERGY DIGS SSE FROM THE PACIFIC NW TO THE COLORADO
FRONT RANGE. ASIDE FROM AN INCREASING LIKELIHOOD OF CIRRUS ADVECTING
INTO THE REGION VIA WSW FLOW ALOFT...FAVORABLE RADIATIONAL COOLING
CONDITIONS WILL OTHERWISE PREVAIL. DUE TO AIRMASS MODIFICATION
ASSOC/W THE ONSET OF A LIGHT SOUTHERLY/SW RETURN FLOW...ANTICIPATE
LOWS A FEW DEGREES WARMER THAN THIS MORNING...IN THE MID TO UPPER
20S. -VINCENT
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 315 PM SATURDAY...
SUN/SUN NIGHT: CHALLENGING TEMPERATURE AND PRECIP FORECAST. THE
ONSET OF WARM ADVECTION...I.E. SOUTHERLY RETURN FLOW EMANATING FROM
THE ATLANTIC /GULF STREAM/...WILL RESULT IN INCREASING CLOUD COVER
AND THE DEVELOPMENT OF A HYBRID OR IN-SITU COLD AIR DAMMING WEDGE.
ELEVATED SHOWER ACTIVITY WILL BE POSSIBLE SUNDAY EVE/NIGHT AS LOW-
LEVEL WARM ADVECTION FURTHER STRENGTHENS ATOP THE SHALLOW COLD AIR
DAMMING WEDGE IN ADVANCE OF A WARM FRONT LIFTING NORTHWARD THROUGH
CENTRAL/EASTERN NC. GIVEN THE EXPECTATION OF BROKEN/OVERCAST
CEILINGS AT LOWER (STRATUS) AND UPPER (CIRRUS) LEVELS...EVAP COOLING
ASSOCIATED WITH AN INITIALLY DRY SURFACE AIRMASS ALONG WITH VIRGA
AND AN INCREASING POTENTIAL FOR ELEVATED SHOWERS...EXPECT CHILLY
AFTERNOON TEMPERATURES RANGING FROM THE UPPER 30S TO MID 40S (NW) TO
MID 40S/LOWER 50S IN THE SE COASTAL PLAIN. EXPECT TEMPERATURES TO
RISE OVERNIGHT FROM SOUTH TO NORTH AS THE LOW-LEVELS SATURATE AND A
WARM FRONT LIFTS NORTHWARD THROUGH CENTRAL/EASTERN NC. TEMPS IN THE
TRIAD MAY HOLD STEADY FOR MUCH OF THE NIGHT...THOUGH A SLOW RISE
STILL APPEARS LIKELY BY SUNRISE. -VINCENT
MONDAY THROUGH MONDAY NIGHT...UPPER TROF ROTATING ACROSS THE UPPER
MIDWEST INTO THE GREAT LAKES WILL PUSH THE STRONG COLD FRONT EAST
ACROSS THE AREA. AMPLITUDE OF THE SYSTEM WILL PROVIDE A DEEP
SOUTHWEST TAP INTO THE GULF AHEAD OF THE FRONT...WITH A PLUME OF
PRECIPITABLE WATER OF 1.5 INCHES EDGING INTO CENTRAL AND EASTERN
NORTH CAROLINA BY AFTERNOON COURTESY OF A 50+ KNOT LOW LEVEL JET AT
H850 STRAIGHT OFF THE GULF. TIMING DISCREPANCIES ARE MINOR
CONCERNING SENSIBLE WEATHER AND WILL MAINTAIN OUR ONGOING
CATEGORICAL POPS IN THE WEST IN THE MORNING PROGRESSING EAST TO THE
I-95 CORRIDOR DURING THE AFTERNOON. SOUTHERLY WINDS AT 10-15 MPH
GUSTING TO 20 WILL VEER SOUTHWEST TO WEST DURING THE AFTERNOON AND
NORTHWEST OVERNIGHT.
HIGHS IN THE EAST WILL HAVE AMPLE TIME TO REACH NEAR 70 PRIOR TO THE
FRONT WHICH PROGS TO A COUPLE OF HUNDRED JOULES OF CAPE. VERTICAL
ALIGNMENT OF THE DEPARTING 150KT UPPER JETS DIFFLUENCE AND
PERTURBATIONS IN THE MID LEVEL FLOW WOULD AID CONVECTIVE DEVELOPMENT
AND WILL EXPAND MENTION OF THUNDER WEST ACROSS THE TRIANGLE AND
SANDHILLS. TEMPERATURES IN THE NORTHWEST ARE A LITTLE MORE UNCERTAIN
DUE TO POTENTIAL FOR IN-SITU LINGERING COOL AIR DUE TO EVAPORATIVE
COOLING SUNDAY NIGHT. THIS WOULD BLOCK THE TRANSITION TO A MORE
PLEASANT SOUTHERLY SURFACE FLOW AND HIGHS WOULD STRUGGLE TO REACH
MID 50S.
THE FRONT WILL BE MOVING SMARTLY ALONG...WITH SHOWERS ENDING AND
CLEARING COMMENCING TOWARDS SUNSET IN THE WEST TO AROUND MIDNIGHT IN
THE EAST. TEMPS WILL PLUMMET AS COLD AIR RUSHES IN AND THICKNESSES
CRASH OVERNIGHT...MONDAY NIGHTS MINS LOOK TO FALL BELOW FREEZING
OVER THE PIEDMONT...WITH MID 30S IN THE EASTERN THIRD OF THE AREA.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 300 PM SATURDAY...
A COLD STRETCH IS ON TAP BEHIND THE FRONT AS POLAR AIR PAYS THE AREA
A VISIT TUESDAY AND WEDNESDAY. THE INITIAL SURGE WILL BE BRISK AND
RAW ON TUESDAY...FEATURING NORTHWEST WIND GUSTING TO 20 MPH AND
THICKNESSES BARELY INDICATIVE OF MID 30S OVER THE NORTHWEST TO LOWER
40S SOUTHEAST. SURFACE HIGH SETTLING OVER THE AREA AND LOOSENING
PRESSURE GRADIENT WILL BE IDEAL FOR RADIATIONAL COOLING AND MINS
WILL BE COLDEST WEDNESDAY MORNING...WITH MOST AREAS WITHIN A COUPLE
OF DEGREES OF 20. SLIGHT DEAMPLIFICATION OF THE TROF AND ANOTHER DAY
OF STRONG INSOLATION WILL PROVIDE SOME VERY MODEST WARMING ON
WEDNESDAY...WITH HIGHS FROM 40 TO 45.
FORECAST FOR LATE WEEK IS MORE UNCERTAIN AS THERE IS MODEL
UNCERTAINTY IN THE SUBSEQUENT EVOLUTION OF THE UPPER TROF AND
STRONGER INDICATIONS OF A SURFACE SYSTEM DEVELOPING AND SKIRTING THE
AREA ON FRIDAY IN THE ECMWF. REGARDLESS...TEMPS WILL MODERATE IN THE
THURSDAY THROUGH SATURDAY TIME FRAME AS THE TROF DEAMPLIFIES AND
HIGHS EACH DAY LOOK TO BE IN THE LOW TO MID 50S...MAYBE A LITTLE
WARMER ON THE WEEKEND AS WE SIT UNDER A STRONG HIGH AND TRANSITION
BRIEFLY TO A LOW AMPLITUDE UPPER RIDGE. AT THIS POINT AM THINKING
ONLY HIGH CLOUDINESS IN THE FASTER FLATTER FLOW AND WILL HAVE ONLY
SLIGHT CHANCE POPS FOR THE FRIDAY NIGHT INTO SATURDAY TIME FRAME.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
AS OF 715 PM SATURDAY...
MODIFIED ARCTIC HIGH PRESSURE...AND AN ASSOCIATED VERY DRY AIR MASS
AND CALM...WILL LINGER OVERHEAD TONIGHT. A SMALL AREA OF SCATTERED
TO BROKEN STRATOCUMULUS MAY DEVELOP IN RETURN FLOW AROUND THE HIGH
FROM NEAR CAPE LOOKOUT NC THIS EVENING TO NEAR AND EAST OF KRWI LATE
TONIGHT-EARLY SUNDAY. STRONGER AND A LONGER FETCH OF RETURN FLOW
UPGLIDE AND MOISTENING AROUND THE HIGH...EVIDENT AS AN AREA OF MVFR
CEILINGS OVER EASTERN GA AND NE FL THIS EVENING...WILL THEN DEVELOP
NORTHWARD THROUGH THE EAST-CENTRAL CAROLINAS THROUGH SUNDAY. THIS
REGIME WILL SUPPORT THE EXPANSION/DEVELOPMENT OF STRATOCUMULUS
CEILINGS...WHOSE BASES WILL PROGRESSIVELY LOWER FROM 5 K TO 2 K
FT...INTO CENTRAL SUNDAY AFTERNOON AND EVENING - FIRST AT KFAY AND
LATEST AT KINT/KGSO. SCATTERED SHOWERS ARE ALSO APT TO DEVELOP IN
THE SAME AREAS ACROSS THE EAST-CENTRAL CAROLINAS...WITH THE RELATIVE
HIGHEST PROBABILITY OF OCCURRENCE AT KFAY DURING THE AFTERNOON...AND
KRWI TOWARD THE VERY END OF THE 00Z TAF PERIOD.
OUTLOOK: CEILINGS WILL CONTINUE TO LOWER INTO IFR-MVFR RANGE
AREAWIDE...WHILE AN AREA OF RAIN OVERSPREADS WESTERN TERMINALS...
SUN NIGHT. THE RAIN WILL LIKELY LOCK KINT AND KGSO INTO A REGIME OF
LIFR-IFR CONDITIONS AND PERIODS OF RAIN AND DRIZZLE...UNTIL A
COLD/OCCLUDED FRONT CROSSES THE AREA LATE MON-EARLY MON NIGHT.
MEANWHILE...CONDITIONS ARE APT TO LIFT AND SCATTER TO MVFR OR EVEN
VFR AT KFAY...KRWI...AND POSSIBLY KRDU AHEAD OF THE COLD FRONT
MONDAY AFTERNOON...BEFORE THE COLD FRONT AND BAND OF SHOWERS CROSSES
THOSE AREAS EARLY MONDAY NIGHT. BLUSTERY NORTHWEST WINDS WILL OCCUR
IN THE WAKE OF THE FRONT MONDAY NIGHT THROUGH TUESDAY...AS ARCTIC
HIGH PRESSURE AND AN ASSOCIATED EXTENDED PERIOD OF VFR
CONDITIONS BUILD IN FROM THE WEST.
&&
THE FOLLOWING ARE RECORD TEMPERATURES THAT WILL BE CHALLENGED
THROUGH THE FORECAST PERIOD:
RECORD LOW:
GSO RDU FAY
WED 11/19 - 20 IN 1951 21 IN 1903 21 IN 1959
THU 11/20 - 12 IN 1951 19 IN 1951 20 IN 1951
RECORD LOW MAX:
GSO RDU FAY
TUE 11/18 - 37 IN 1924 35 IN 1924 46 IN 2008
WED 11/19 - 34 IN 1951 36 IN 1951 41 IN 2000
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...VINCENT
SHORT TERM...VINCENT
LONG TERM...MONEYPENNY
AVIATION...MWS
CLIMATE...MWS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1205 AM CST FRI NOV 14 2014
.UPDATE...
ISSUED AT 1205 AM CST FRI NOV 14 2014
LATEST SURFACE ANALYSIS SHOWS A 1033MB HIGH PRESSURE STRETCHING
FROM EASTERN MONTANA INTO SOUTH CENTRAL NORTH DAKOTA. LIGHT WINDS
AND A MOSTLY CLEAR SKY CONTINUES FOR MOST OF WESTERN AND CENTRAL
NORTH DAKOTA. THE EXCEPTION IS LOCALIZED PATCHY FOG AND LOW CLOUDS
AT HETTINGER...AND A LARGER AREA OF STRATUS ALONG LAKE SAKAKAWEA.
GIVEN THE LIGHT WINDS...TEMPERATURE/DEWPOINT SPREADS AND LOCATION
OF SURFACE HIGH OVERNIGHT...AND CURRENT FOG/STRATUS LOOP...HAVE
MENTIONED PATCHY FOG MAINLY NORTHWEST THROUGH SOUTH CENTRAL AND
INTO PORTIONS OF THE SOUTHWEST. LATEST HRRR CIG/VSBY FORECAST DOES
ADVERTISE INCREASING LOW CLOUDS INTO ADAMS/HETTINGER/GRANT/SIOUX
COUNTIES OVERNIGHT INTO MID MORNING FRIDAY. POTENTIAL IS THERE AS
A SOUTHEAST WIND DEVELOPS OVERNIGHT IN RESPONSE TO THE AFOREMENTIONED
HIGH PRESSURE OVER SOUTH CENTRAL NORTH DAKOTA SHIFTING INTO EASTERN
SOUTH DAKOTA. WILL MONITOR THIS AND THE WIND CHILL ADVISORY FOR
THE SOUTHWEST...WHICH STILL REMAINS ON TRACK.
UPDATE ISSUED AT 947 PM CST THU NOV 13 2014
TEMPERATURES CONTINUE TO DROP QUICKLY THIS EVENING UNDER A COLD
SURFACE RIDGE FROM EASTERN SOUTH DAKOTA NORTH NORTHWEST INTO
WESTERN NORTH DAKOTA. ALREADY AT 9 PM THE TEMPERATURE WAS DOWN TO
-15 AT HETTINGER AND -13 IN GLEN ULLIN. NEEDLESS TO SAY...WE HAVE
LOWERED TEMPERATURES ACROSS MOST OF WESTERN AND CENTRAL NORTH
DAKOTA. EVEN IN EASTERN PORTIONS OF CENTRAL NORTH DAKOTA WITH
LITTLE SNOW...ROLLA WAS DOWN TO 1 ABOVE.
REGARDING THE WIND CHILL ADVISORY...WIND CHILLS WERE CURRENTLY IN
THE 10 TO 20 BELOW RANGE OVER THE ADVISORY AREA...WITH THE
EXCEPTION OF DICKINSON WHICH WAS -24. THINK THE COLDEST WIND
CHILLS WILL COME LATER TONIGHT AS THE SURFACE HIGH SHIFTS EAST AND
A SOUTH TO SOUTHEAST FLOW INCREASES SLIGHTLY OVER THE SOUTHWEST.
WILL NEED TO KEEP AN EYE ON THE FAR SOUTH CENTRAL WHERE LOWERING
TEMPERATURES HAS RESULTED IN WIND CHILLS CLOSE TO ADVISORY
CRITERIA. WILL LET IT RIDE FOR NOW AS THE LOWEST WIND CHILLS WOULD
LIKELY OCCUR AROUND 12 UTC. THIS WOULD GIVE THE OVERNIGHT CREW
TIME TO ISSUE SOMETHING FOR THE EARLY MORNING IF TEMPERATURES DROP
MORE THAN FORECAST.
OTHERWISE...NO ISSUES WITH CLEAR SKIES EXCEPT FOR SOME STRATUS
COMING OFF THE LAKES.
UPDATE ISSUED AT 556 PM CST THU NOV 13 2014
HIGH PRESSURE CENTERED OVER THE NORTHERN AND CENTRAL PLAINS WILL
DRIFT SOUTHEAST TONIGHT. MOSTLY CLEAR SKIES ACROSS WESTERN AND
CENTRAL NORTH DAKOTA. A FEW SCATTERED CLOUDS FROM SOUTHEAST
SASKATCHEWAN INTO NORTH CENTRAL NORTH DAKOTA...WITH SOME LOWER
STRATUS COMING OFF LAKE SAKAKAWEA. ONLY ADJUSTMENTS WERE TO LOWER
SKY COVER MOST AREAS AND POPULATE THE LATEST SENSIBLE WEATHER
ELEMENTS. EXPECT TEMPERATURES TO DROP QUICKLY THIS EVENING...WHICH
IS HANDLED WELL IN THE CURRENT FORECAST. NO CHANGES TO CURRENT
WIND CHILL ADVISORY.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 350 PM CST THU NOV 13 2014
CURRENT SURFACE ANALYSIS PLACES BROAD FRIGID HIGH OVER THE
NORTHERN INTO THE CENTRAL PLAINS. UPPER LEVEL ANALYSIS PLACES LOW
HEADING OVER EASTERN CANADA WITH WEAK CYCLONIC FLOW REMAINING OVER
OUR AREA AS BLOCKING RIDGE REMAINS OFF THE WEST COAST.
FOR TONIGHT...BROAD SURFACE HIGH WILL BRING THE COLDEST NIGHT OF
THE SEASON TO THE AREA...WITH THE COLDEST LOCATIONS OVER SOUTHWESTERN
NORTH DAKOTA OVER THE RECENT SNOW PACK. THIS COLD WILL COMBINE WITH
LIGHT WINDS TO BRING FRIGID WINDCHILL VALUES...THUS A WIND CHILL
ADVISORY HAS BEEN ISSUED FOR THIS AREA. OTHERWISE...SKIES WILL
SLOWLY CLEAR OUT AS UPPER LOW CONTINUES ITS EASTWARD PROGRESSION.
ON FRIDAY...QUIET AND COLD WEATHER IS EXPECTED AS BLOCKING PATTERN
REMAINS. HIGH TEMPERATURES WILL REMAIN IN THE TEENS THROUGHOUT THE
AREA.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 350 PM CST THU NOV 13 2014
CONTINUED COLD THROUGH THE PERIOD AND BLOWING SNOW POTENTIAL
SUNDAY HIGHLIGHT THE EXTENDED FORECAST.
TODAYS 12Z MODELS CONTINUE TO DEPICT A BLOCKING HIGH AMPLITUDE UPPER
LEVEL RIDGE ACROSS THE EASTERN PACIFIC...WITH A DEEP LONGWAVE UPPER
LEVEL TROUGH ACROSS NORTH AMERICA. THE MODELS HINT THAT THIS PATTERN
MAY BEGIN TO BREAK DOWN TOWARDS THE MIDDLE/END OF NEXT WEEK.
FRIDAY NIGHT AND SATURDAY NORTH DAKOTA SHOULD BE UNDER THE INFLUENCE
OF COLD HIGH PRESSURE CENTERED ALONG THE FRONT RANGE...AS A LOW
PRESSURE SYSTEM SOUTH OF THE STATE PROGRESSES EAST ACROSS THE
CENTRAL AND SOUTHERN PLAINS. LOWS FRIDAY NIGHT FROM 5 ABOVE TO 10
BELOW ZERO...HIGHS SATURDAY FROM 5 TO 15 ABOVE ZERO.
SATURDAY NIGHT A STRONG UPPER LEVEL SHORTWAVE...PART OF THE WESTERN
LOBE OF THE COLD HUDSON BAY LOW...IS FORECAST TO MOVE SOUTH ACROSS
CENTRAL CANADA AND APPROACH THE NORTH DAKOTA BORDER. THIS WILL KEEP
WESTERLY WINDS OF 15 TO 20 MPH SATURDAY NIGHT - AND LOWS SATURDAY
NIGHT SHOULD NOT BE AS COLD AS FRIDAY NIGHT: FROM JUST BELOW ZERO TO
NEAR 10 ABOVE ZERO.
ON SUNDAY THE UPPER LEVEL SHORTWAVE MOVES SOUTH ACROSS NORTH
DAKOTA...BRINGING A STRONG COLD FRONT ACROSS THE STATE. LOOKING AT
NORTHWEST WINDS OF 25 TO 35 MPH - WITH GUSTS TO 40 MPH POSSIBLE. AT
THIS TIME IT APPEARS THE SOUTHWEST PART OF THE STATE WOULD SEE THE
STRONGEST WINDS - AND A WIND ADVISORY POSSIBLE DAYTIME SUNDAY. THE
GOOD NEWS IS THAT HIGHS SUNDAY SHOULD BE IN THE 15 TO 25 ABOVE RANGE.
COLD AIR BEHIND THE SUNDAY COLD FRONT WILL KEEP TEMPERATURES WELL
BELOW AVERAGE...WITH LOWS SUNDAY NIGHT ZERO TO 5 ABOVE...HIGHS
MONDAY 10 TO 15 ABOVE...AND LOWS MONDAY NIGHT 5 BELOW TO 5 ABOVE.
A BIT WARMER TUESDAY THROUGH THURSDAY AS IT APPEARS THE EASTERN
PACIFIC RIDGE BREAKS DOWN...WITH HIGHS IN THE 20S AND LOWS 5 TO 15
ABOVE ZERO. THERE IS A HINT OF A CHANCE OF SNOW TOWARDS THE END OF
NEXT WEEK AS A MORE PROGRESSIVE PATTERN WITH A SERIES OF LOW
PRESSURE SYSTEMS MOVING EAST ACROSS NORTH AMERICA.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1205 AM CST FRI NOV 14 2014
COLD SURFACE RIDGE EXTENDING FROM EASTERN SOUTH DAKOTA INTO
NORTHWEST NORTH DAKOTA. GENERALLY VFR CONDITIONS ARE EXPECTED
THROUGH THE 06Z TAF PERIOD. HOWEVER...LIGHT SOUTHERLY FLOW IS
EXPECTED TO TRANSPORT LOW LEVEL MOISTURE NORTH INTO WESTERN NORTH
DAKOTA LATE TONIGHT INTO FRIDAY MORNING. THIS COULD BRING LOW LEVEL
STRATUS INTO SOUTHWEST NORTH DAKOTA AROUND 12 UTC AND COULD APPROACH
KDIK AND KBIS AROUND 15-18 UTC. NOT SURE ABOUT THE EXTENT OF
MOISTURE TRANSPORT SO HAVE STARTED WITH A SCATTERED LOWER STRATUS
LAYER AT THESE SITES THURSDAY MORNING. OVERNIGHT SHIFT CAN MONITOR
THE PROGRESSION AND UPDATE AS NEEDED. ELSEWHERE...ADDED A TEMPO FOR
PATCHY FOG AT KISN FROM 10-13 UTC DUE TO THE PROXIMITY OF THE LAKE
AND A LIGHT SURFACE FLOW.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
WIND CHILL ADVISORY UNTIL 8 AM MST FRIDAY FOR NDZ031>033-040-041-
043-044.
&&
$$
UPDATE...KS
SHORT TERM...JJS
LONG TERM...JMV
AVIATION...TWH
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
953 PM EST SAT NOV 15 2014
.SYNOPSIS...
SURFACE HIGH PRESSURE WILL MOVE EAST OF THE AREA TONIGHT. A STORM
SYSTEM WILL MOVE INTO THE AREA SUNDAY NIGHT...PROVIDING
ACCUMULATING SNOW THROUGH MONDAY MORNING. BEHIND A STRONG COLD
FRONT...WHICH IS EXPECTED TO PASS THROUGH THE REGION MONDAY
AFTERNOON...VERY COLD AIR IS EXPECTED THROUGH THE MIDDLE OF THE
WEEK.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
WEAK S/W IN THE SW FLOW ALOFT IS BRINGING SOME LIFT TO THE OHIO
VALLEY THIS EVENING. OBS IN ERN IL ARE NOW REPORTING LIGHT SNOW.
EXPECT THIS AREA TO LIFT ACROSS THE REGION AFTER MIDNIGHT...BUT DO
NOT EXPECT ANY REAL ACCUMULATIONS...MOSTLY A DUSTING TO A FEW
TENTHS OF AN INCH IN SE INDIANA AND THRU OHIO.
TEMPERATURES ARE EXPECTED TO REMAIN CLOSE TO STEADY THROUGH THE
REST OF THE NIGHT.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY/...
THE FIRST WIDESPREAD ACCUMULATING SNOWFALL OF THE SEASON APPEARS A
NEAR-CERTAINTY AT THIS POINT...AND THIS SYSTEM (SUNDAY NIGHT INTO
MONDAY MORNING) REMAINS THE FOCUS FOR THE SHORT TERM OF THE
FORECAST.
A LULL IN ACTIVITY IS EXPECTED FOR SUNDAY MORNING AND INTO THE
AFTERNOON. SSW WIND FLOW OF AROUND 10 KNOTS WILL HELP TEMPERATURES
MAKE SOME ADVECTION-INDUCED INCREASES FOR THE FIRST TIME IN
SEVERAL DAYS. THE MAX TEMP FORECAST RANGES FROM UPPER 30S IN THE
NORTHWEST TO LOWER 40S IN THE SOUTHEAST. HOWEVER...TEMPERATURES ON
SUNDAY ARE ONE OF THE PRIMARY SOURCES OF UNCERTAINTY FOR THE
INCOMING WEATHER SYSTEM...AS WILL BE DISCUSSED BELOW.
A LARGE MID-LEVEL TROUGH IS FORECAST TO MOVE SSW FROM THE CANADIAN
PLAINS INTO THE GREAT LAKES ON MONDAY. THE OHIO VALLEY IS IN A
FAVORABLE REGION FOR LIFT AHEAD OF THIS TROUGH...WITH INCREASING
UPPER DIVERGENCE (AS 300MB FLOW STRENGTHENS ACROSS THE LOWER GREAT
LAKES). LOW-LEVEL FORCING DOES NOT APPEAR TO BE PARTICULARLY
STRONG...WITH A VERY WEAK AND ILL-DEFINED SURFACE LOW EXPECTED TO
MOVE NORTHEAST THROUGH OHIO AND WEST VIRGINIA BY MONDAY MORNING.
THERE IS HIGH CONFIDENCE IN THE GENERAL ARRANGEMENT OF
PRECIPITATION (COVERED WITH A LARGE SWATH OF 100-POPS IN THE
GRIDS)...AND MODERATE CONFIDENCE IN QPF.
BOUNDARY LAYER THERMODYNAMICS PROVIDE THE BIGGEST CONCERN FOR THE
FORECAST...AS A RAIN/SNOW TRANSITION ZONE IS EXPECTED TO EXIST
ACROSS THE HEART OF THE FORECAST AREA WHEN PRECIPITATION BEGINS ON
SUNDAY EVENING. MODEL SOUNDINGS SUGGEST THAT AFTER
SATURATION...THE LOWEST 5000 FEET WILL BE NEARLY ISOTHERMAL
(DROPPING ONLY SLIGHTLY IN TEMPERATURE WITH HEIGHT). THIS MAKES
THE RAIN/SNOW TRANSITION FORECAST VERY SENSITIVE TO TEMPERATURES
IN THE LOW LEVELS. UNFORTUNATELY...THE SPREAD IN MODEL SURFACE TEMPS
IS GREATER THAN WOULD BE PREFERRED JUST 24-36 HOURS AWAY. WITH A
SLIGHT TREND TOWARD WARMER TEMPERATURES NOTED IN THE 12Z
RUNS...BUT A LACK OF CONFIDENCE IN GETTING THOSE NUMBERS NAILED
DOWN...IT IS CLEAR THAT THERE IS STILL SOME BUST POTENTIAL IN THE
SNOWFALL FORECAST WITH THIS SYSTEM. ANOTHER ITEM TO FACTOR IN IS
THAT SNOW RATIOS ARE NOT EXPECTED TO BE VERY HIGH...WITH MOST OF
THE MOISTURE WITHIN A FEW DEGREES OF THE FREEZING MARK...AND
LITTLE CONTRIBUTION FROM THE -12C TO -18C DENDRITIC GROWTH ZONE.
NONETHELESS...DESPITE THESE CONCERNS...AFTER ALL THE MATH WAS DONE
(SNOW RATIOS / QPF / TEMPERATURE TIMING) THE NEW TOTALS CAME OUT
SLIGHTLY HIGHER THAN THE PREVIOUS FORECAST. ACROSS THE ILN
CWA...THIS ALLOWS FOR THE HIGHEST TOTALS TO OCCUR ON AN AXIS FROM
CARROLL COUNTY KENTUCKY TO LICKING COUNTY OHIO...ON THE
INTERSTATE 71 CORRIDOR. ALONG THIS STRETCH OF COUNTIES...CURRENT
FORECAST DATA SUGGESTS THAT UP TO THREE INCHES IS A REASONABLE
FORECAST...WITH SOME POTENTIAL FOR SLIGHTLY HIGHER AMOUNTS. WPC
GRAPHICS / SREF PLOTS / GFS-SOUNDING-BASED COBB DATA SUGGEST SOME
POTENTIAL FOR A MORE WIDESPREAD 4-INCH SNOWFALL...THOUGH THIS WILL
NOT BE USED IN THE FORECAST TODAY. LESSER AMOUNTS ARE EXPECTED
FURTHER NORTH (DUE TO LESS FAVORABLE FORCING) AND FURTHER SOUTH
(DUE TO A GREATER MIX WITH RAIN). WHILE IT SEEMS LIKELY THAT
ADVISORIES WILL EVENTUALLY BE NEEDED...COLLABORATION WITH THE
MAJORITY OF SURROUNDING OFFICES REVEALED SIMILAR CONCERNS WITH THE
TEMPERATURE ISSUES...AND NOT ENOUGH CONFIDENCE TO PIGEONHOLE
SPECIFIC HEADLINE PRODUCTS 24-36 HOURS OUT.
SNOW IS EXPECTED TO END FROM WEST TO EAST DURING THE FIRST HALF OF
MONDAY...WITH ANOTHER STRONG SURFACE COLD FRONT COMING IN A FEW
HOURS BEHIND. TEMPERATURES WILL DROP MARKEDLY BEHIND THE
FRONT...AS WINDS BECOME GUSTY (20-25 KNOTS) AS COLD ADVECTION BEGINS.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
NEW SURGE OF ARCTIC AIR WILL OVERSPREAD THE AREA MONDAY NIGHT.
MODELS INDICATE CAA AND MOISTURE AROUND 850 MB WHICH SHOULD RESULT
IN A STRATOCUMULUS DECK. AS IS SOMETIMES THE CASE WITH COLD ARCTIC
AIR...HARD TO KNOW AT THIS POINT IF THE CLOUDS WILL THIN SOME TOWARD
TUESDAY MORNING. IF THIS OCCURS...AND DEPENDING ON WHERE
ACCUMULATING SNOW ENDS UP BEING...CURRENT FORECAST LOWS COULD BE
COLDER. WITH THE COLD TEMPERATURES...THE DENDRITIC GROWTH ZONE WILL
BE INTERSECTING THE LOW LEVEL MOISTURE. AS WE HAVE SEEN THE LAST
COUPLE OF DAYS...MODELS USUALLY DO NOT INDICATE MEASURABLE
PCPN...BUT FEEL SOME FLURRIES WILL BE ABLE TO SQUEEZE OUT OF THE
CLOUDS DESPITE LIMITED MOISTURE. HAVE GONE WITH A CHANCE OF
FLURRIES. LOWS WILL BOTTOM OUT IN THE 10-15 DEGREE RANGE. RECORD
LOWS WILL BE APPROACHED AND PERHAPS BROKEN BASED ON AFOREMENTIONED
SCENARIO. ALSO...THE PRESSURE GRADIENT WILL BE INCREASING AS LOW
PRESSURE DEEPENS OVER QUEBEC. BLUSTERY CONDITIONS WILL DROP WIND
CHILL VALUES INTO THE 0 TO -5 RANGE.
ON TUESDAY...THE COLDEST AIR IS STILL EXPECTED TO ARRIVE OVER THE
GREAT LAKES AND OHIO VALLEY AS DEEP/ANOMALOUS UPR LVL TROUGH SETTLES
IN. MODELS ARE STILL CONSISTENT IN FORECASTING 850 MB TEMPS NEAR -18
C WHICH IS IN THE -3 TO -4 SIGMA VALUES FOR CLIMATE NORMALS FOR MID
NOVEMBER. BELIEVE THE RECORD LOW MAX HIGHS FOR DAYTON...CINCINNATI
AND COLUMBUS...27...26...26 RESPECTIVELY ARE IN JEOPARDY. UNDER
PARTLY TO MOSTLY CLOUDY SKIES IN THE CAA...AM FORECASTING HIGHS IN
THE LOWER 20S. IT IS CONCEIVABLE THAT HIGHS MAY BE COLDER BUT WANT
TO WAIT TO SEE HOW THE SNOW COVER AND CLOUDS PAN OUT. IT WILL BE
BLUSTERY WITH A CHANCE OF FLURRIES.
FOR TUESDAY NIGHT...HIGH PRESSURE IS EXPECTED TO BUILD INTO THE SE
UNITED STATES. IT WILL BEGIN TO WARM AIR ADVECT ALOFT WHICH SHOULD
PUSH STRATOCUMULUS AND FLURRY THREAT TO THE EAST DURING THE EVENING.
MID AND HIGH LEVEL CLOUDS WILL THEN INCREASE FROM THE NORTHWEST IN
ADVANCE OF THE NEXT WEATHER SYSTEM. HAVE TAKEN A BLEND OF MODELS FOR
LOWS GIVEN THERE WILL STILL BE A PRESSURE GRADIENT AND CLOUDS FROM
TIME TO TIME. WILL FORECAST 10 TO 15 WITH WIND CHILL VALUES ONCE
AGAIN IN THE 0 TO -5 RANGE.
MODELS ARE IN GOOD AGREEMENT FOR WEDNESDAY INTO WEDNESDAY
NIGHT...THEN THE ECMWF BECOMES THE ODD MODEL OUT IN THE REMAINDER OF
THE EXTENDED. HAVE GONE WITH WPC GUIDANCE WHICH FAVORS A GFS SOLUTION
AT THIS TIME.
S/WV AND WEAK FRONT IS EXPECTED TO PASS THROUGH THE REGION WEDNESDAY
INTO WEDNESDAY NIGHT. SYSTEM IS FAIRLY MOISTURE STARVED AND HAVE
LIMITED LOW POPS/THREAT FOR LIGHT SNOW TO THE NRN ZONES. IT WILL BE
BLUSTERY ONCE AGAIN AS TEMPERATURES WARM INTO THE LOWER AND MID
30S...BUT STILL WELL BELOW NORMAL FOR MID NOVEMBER.
FOR THE REMAINDER OF THE EXTENDED....COLD WEATHER WILL CONTINUE INTO
THE END OF THE WORK WEEK AS HIGH PRESSURE AND ANOTHER SHOT OF COLD
AIR MOVE INTO THE REGION. MODELS HAVE BEEN ADVERTISING A PATTERN
SHIFT BY THE WEEKEND. LOOKS LIKE LONGWAVE PATTERN WILL PUSH ARCTIC
AIR BACK NORTH INTO CANADA AS THE NEXT WEATHER SYSTEM APPROACHING
THE REGION FROM THE WEST IS OF PACIFIC ORIGIN. TEMPERATURES WILL
MODERATE INTO THE WEEKEND WITH PERHAPS A THREAT OF SHOWERS IN THE
WAA PATTERN SATURDAY AFTERNOON OR NIGHT.
&&
.AVIATION /03Z SUNDAY THROUGH THURSDAY/...
FAST SW FLOW ALOFT WILL ALLOW THE CLOUDS TO THICKEN AND CIGS TO LOWER
THROUGHOUT THE NIGHT. MANY OF THE 12Z MODELS BROUGHT A H5
DISTURBANCE THROUGH TONIGHT...WHICH BROUGHT SOME LIGHT SNOW.
18Z RUN OF THE NAM AND LATEST RUNS OF THE RAP AND HRRR ARE SHOWING
A LOWER CHANCE OF THIS. HAVE BACKED OFF ANY PCPN MENTION TONIGHT
TO A VCSH.
CIGS WILL CONTINUE TO LOWER ON SUNDAY...BUT SHOULD STAY VFR
THROUGH THE PERIOD. IN THE 30 HOUR CVG TAF...AFT 00Z MONDAY BROUGHT
IN PREVAILING RAIN/SNOW MIX WITH MVFR CONDITIONS.
OUTLOOK...MVFR/IFR CEILINGS AND VISIBILITIES WITH SNOW ARE
POSSIBLE SUNDAY NIGHT INTO MONDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...HATZOS
NEAR TERM...SITES
SHORT TERM...HATZOS
LONG TERM...HICKMAN
AVIATION...SITES
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
712 PM EST SAT NOV 15 2014
.SYNOPSIS...
SURFACE HIGH PRESSURE WILL MOVE EAST OF THE AREA TONIGHT. A STORM
SYSTEM WILL MOVE INTO THE AREA SUNDAY NIGHT...PROVIDING
ACCUMULATING SNOW THROUGH MONDAY MORNING. BEHIND A STRONG COLD
FRONT...WHICH IS EXPECTED TO PASS THROUGH THE REGION MONDAY
AFTERNOON...VERY COLD AIR IS EXPECTED THROUGH THE MIDDLE OF THE
WEEK.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
RELATIVELY QUIET CONDITIONS ARE EXPECTED THROUGH THE NEXT 12
HOURS...BUT THE NEAR TERM FORECAST IS NOT WITHOUT ONE MINOR
COMPLICATION. A VERY WEAK SHORTWAVE CURRENTLY OVER MISSOURI IS
MOVING QUICKLY EAST-NORTHEAST IN THE MID-LEVEL FLOW...AND IS
FORECAST TO PASS OVER THE OHIO VALLEY OVERNIGHT AS IT WEAKENS EVEN
FURTHER. NAM RUNS HAVE INTERMITTENTLY PRODUCED QPF WITH THIS
SYSTEM...WHILE GFS/ECMWF RUNS HAVE GENERALLY BEEN DRY. JUDGING BY
HIGH-RES GUIDANCE (SUCH AS THE WRF-ARW AND HRRR)...THE SHORTWAVE
MAY HAVE JUST ENOUGH STRENGTH LEFT TO PRODUCE SOME SNOW OUT OF A
CLOUD DECK THAT WILL PROBABLY REMAIN ABOVE 4000 FEET. AT MOST...A
FEW TENTHS OF AN INCH MAY FALL...BUT THE SYSTEM WILL BE MOVING SO
QUICKLY THAT A DUSTING IS A MORE LIKELY SCENARIO.
TEMPERATURES TODAY HAVE MANAGED TO CLEAR THE FREEZING MARK BY
AT LEAST A FEW DEGREES. WITH LIGHT WINDS AND SKIES COVERED ONLY BY
HIGH CLOUDS...A DROP IN TEMPERATURES TO THE UPPER 20S IS EXPECTED
DURING THE FIRST HALF OF THE OVERNIGHT HOURS. AFTER THAT...AS
SOUTHERLY FLOW BEGINS AND CLOUDS START TO THICKEN...TEMPERATURES
WILL LIKELY REMAIN STEADY THROUGH THE REST OF THE NIGHT.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY/...
THE FIRST WIDESPREAD ACCUMULATING SNOWFALL OF THE SEASON APPEARS A
NEAR-CERTAINTY AT THIS POINT...AND THIS SYSTEM (SUNDAY NIGHT INTO
MONDAY MORNING) REMAINS THE FOCUS FOR THE SHORT TERM OF THE
FORECAST.
A LULL IN ACTIVITY IS EXPECTED FOR SUNDAY MORNING AND INTO THE
AFTERNOON. SSW WIND FLOW OF AROUND 10 KNOTS WILL HELP TEMPERATURES
MAKE SOME ADVECTION-INDUCED INCREASES FOR THE FIRST TIME IN
SEVERAL DAYS. THE MAX TEMP FORECAST RANGES FROM UPPER 30S IN THE
NORTHWEST TO LOWER 40S IN THE SOUTHEAST. HOWEVER...TEMPERATURES ON
SUNDAY ARE ONE OF THE PRIMARY SOURCES OF UNCERTAINTY FOR THE
INCOMING WEATHER SYSTEM...AS WILL BE DISCUSSED BELOW.
A LARGE MID-LEVEL TROUGH IS FORECAST TO MOVE SSW FROM THE CANADIAN
PLAINS INTO THE GREAT LAKES ON MONDAY. THE OHIO VALLEY IS IN A
FAVORABLE REGION FOR LIFT AHEAD OF THIS TROUGH...WITH INCREASING
UPPER DIVERGENCE (AS 300MB FLOW STRENGTHENS ACROSS THE LOWER GREAT
LAKES). LOW-LEVEL FORCING DOES NOT APPEAR TO BE PARTICULARLY
STRONG...WITH A VERY WEAK AND ILL-DEFINED SURFACE LOW EXPECTED TO
MOVE NORTHEAST THROUGH OHIO AND WEST VIRGINIA BY MONDAY MORNING.
THERE IS HIGH CONFIDENCE IN THE GENERAL ARRANGEMENT OF
PRECIPITATION (COVERED WITH A LARGE SWATH OF 100-POPS IN THE
GRIDS)...AND MODERATE CONFIDENCE IN QPF.
BOUNDARY LAYER THERMODYNAMICS PROVIDE THE BIGGEST CONCERN FOR THE
FORECAST...AS A RAIN/SNOW TRANSITION ZONE IS EXPECTED TO EXIST
ACROSS THE HEART OF THE FORECAST AREA WHEN PRECIPITATION BEGINS ON
SUNDAY EVENING. MODEL SOUNDINGS SUGGEST THAT AFTER
SATURATION...THE LOWEST 5000 FEET WILL BE NEARLY ISOTHERMAL
(DROPPING ONLY SLIGHTLY IN TEMPERATURE WITH HEIGHT). THIS MAKES
THE RAIN/SNOW TRANSITION FORECAST VERY SENSITIVE TO TEMPERATURES
IN THE LOW LEVELS. UNFORTUNATELY...THE SPREAD IN MODEL SURFACE TEMPS
IS GREATER THAN WOULD BE PREFERRED JUST 24-36 HOURS AWAY. WITH A
SLIGHT TREND TOWARD WARMER TEMPERATURES NOTED IN THE 12Z
RUNS...BUT A LACK OF CONFIDENCE IN GETTING THOSE NUMBERS NAILED
DOWN...IT IS CLEAR THAT THERE IS STILL SOME BUST POTENTIAL IN THE
SNOWFALL FORECAST WITH THIS SYSTEM. ANOTHER ITEM TO FACTOR IN IS
THAT SNOW RATIOS ARE NOT EXPECTED TO BE VERY HIGH...WITH MOST OF
THE MOISTURE WITHIN A FEW DEGREES OF THE FREEZING MARK...AND
LITTLE CONTRIBUTION FROM THE -12C TO -18C DENDRITIC GROWTH ZONE.
NONETHELESS...DESPITE THESE CONCERNS...AFTER ALL THE MATH WAS DONE
(SNOW RATIOS / QPF / TEMPERATURE TIMING) THE NEW TOTALS CAME OUT
SLIGHTLY HIGHER THAN THE PREVIOUS FORECAST. ACROSS THE ILN
CWA...THIS ALLOWS FOR THE HIGHEST TOTALS TO OCCUR ON AN AXIS FROM
CARROLL COUNTY KENTUCKY TO LICKING COUNTY OHIO...ON THE
INTERSTATE 71 CORRIDOR. ALONG THIS STRETCH OF COUNTIES...CURRENT
FORECAST DATA SUGGESTS THAT UP TO THREE INCHES IS A REASONABLE
FORECAST...WITH SOME POTENTIAL FOR SLIGHTLY HIGHER AMOUNTS. WPC
GRAPHICS / SREF PLOTS / GFS-SOUNDING-BASED COBB DATA SUGGEST SOME
POTENTIAL FOR A MORE WIDESPREAD 4-INCH SNOWFALL...THOUGH THIS WILL
NOT BE USED IN THE FORECAST TODAY. LESSER AMOUNTS ARE EXPECTED
FURTHER NORTH (DUE TO LESS FAVORABLE FORCING) AND FURTHER SOUTH
(DUE TO A GREATER MIX WITH RAIN). WHILE IT SEEMS LIKELY THAT
ADVISORIES WILL EVENTUALLY BE NEEDED...COLLABORATION WITH THE
MAJORITY OF SURROUNDING OFFICES REVEALED SIMILAR CONCERNS WITH THE
TEMPERATURE ISSUES...AND NOT ENOUGH CONFIDENCE TO PIGEONHOLE
SPECIFIC HEADLINE PRODUCTS 24-36 HOURS OUT.
SNOW IS EXPECTED TO END FROM WEST TO EAST DURING THE FIRST HALF OF
MONDAY...WITH ANOTHER STRONG SURFACE COLD FRONT COMING IN A FEW
HOURS BEHIND. TEMPERATURES WILL DROP MARKEDLY BEHIND THE
FRONT...AS WINDS BECOME GUSTY (20-25 KNOTS) AS COLD ADVECTION BEGINS.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
NEW SURGE OF ARCTIC AIR WILL OVERSPREAD THE AREA MONDAY NIGHT.
MODELS INDICATE CAA AND MOISTURE AROUND 850 MB WHICH SHOULD RESULT
IN A STRATOCUMULUS DECK. AS IS SOMETIMES THE CASE WITH COLD ARCTIC
AIR...HARD TO KNOW AT THIS POINT IF THE CLOUDS WILL THIN SOME TOWARD
TUESDAY MORNING. IF THIS OCCURS...AND DEPENDING ON WHERE
ACCUMULATING SNOW ENDS UP BEING...CURRENT FORECAST LOWS COULD BE
COLDER. WITH THE COLD TEMPERATURES...THE DENDRITIC GROWTH ZONE WILL
BE INTERSECTING THE LOW LEVEL MOISTURE. AS WE HAVE SEEN THE LAST
COUPLE OF DAYS...MODELS USUALLY DO NOT INDICATE MEASURABLE
PCPN...BUT FEEL SOME FLURRIES WILL BE ABLE TO SQUEEZE OUT OF THE
CLOUDS DESPITE LIMITED MOISTURE. HAVE GONE WITH A CHANCE OF
FLURRIES. LOWS WILL BOTTOM OUT IN THE 10-15 DEGREE RANGE. RECORD
LOWS WILL BE APPROACHED AND PERHAPS BROKEN BASED ON AFOREMENTIONED
SCENARIO. ALSO...THE PRESSURE GRADIENT WILL BE INCREASING AS LOW
PRESSURE DEEPENS OVER QUEBEC. BLUSTERY CONDITIONS WILL DROP WIND
CHILL VALUES INTO THE 0 TO -5 RANGE.
ON TUESDAY...THE COLDEST AIR IS STILL EXPECTED TO ARRIVE OVER THE
GREAT LAKES AND OHIO VALLEY AS DEEP/ANOMALOUS UPR LVL TROUGH SETTLES
IN. MODELS ARE STILL CONSISTENT IN FORECASTING 850 MB TEMPS NEAR -18
C WHICH IS IN THE -3 TO -4 SIGMA VALUES FOR CLIMATE NORMALS FOR MID
NOVEMBER. BELIEVE THE RECORD LOW MAX HIGHS FOR DAYTON...CINCINNATI
AND COLUMBUS...27...26...26 RESPECTIVELY ARE IN JEOPARDY. UNDER
PARTLY TO MOSTLY CLOUDY SKIES IN THE CAA...AM FORECASTING HIGHS IN
THE LOWER 20S. IT IS CONCEIVABLE THAT HIGHS MAY BE COLDER BUT WANT
TO WAIT TO SEE HOW THE SNOW COVER AND CLOUDS PAN OUT. IT WILL BE
BLUSTERY WITH A CHANCE OF FLURRIES.
FOR TUESDAY NIGHT...HIGH PRESSURE IS EXPECTED TO BUILD INTO THE SE
UNITED STATES. IT WILL BEGIN TO WARM AIR ADVECT ALOFT WHICH SHOULD
PUSH STRATOCUMULUS AND FLURRY THREAT TO THE EAST DURING THE EVENING.
MID AND HIGH LEVEL CLOUDS WILL THEN INCREASE FROM THE NORTHWEST IN
ADVANCE OF THE NEXT WEATHER SYSTEM. HAVE TAKEN A BLEND OF MODELS FOR
LOWS GIVEN THERE WILL STILL BE A PRESSURE GRADIENT AND CLOUDS FROM
TIME TO TIME. WILL FORECAST 10 TO 15 WITH WIND CHILL VALUES ONCE
AGAIN IN THE 0 TO -5 RANGE.
MODELS ARE IN GOOD AGREEMENT FOR WEDNESDAY INTO WEDNESDAY
NIGHT...THEN THE ECMWF BECOMES THE ODD MODEL OUT IN THE REMAINDER OF
THE EXTENDED. HAVE GONE WITH WPC GUIDANCE WHICH FAVORS A GFS SOLUTION
AT THIS TIME.
S/WV AND WEAK FRONT IS EXPECTED TO PASS THROUGH THE REGION WEDNESDAY
INTO WEDNESDAY NIGHT. SYSTEM IS FAIRLY MOISTURE STARVED AND HAVE
LIMITED LOW POPS/THREAT FOR LIGHT SNOW TO THE NRN ZONES. IT WILL BE
BLUSTERY ONCE AGAIN AS TEMPERATURES WARM INTO THE LOWER AND MID
30S...BUT STILL WELL BELOW NORMAL FOR MID NOVEMBER.
FOR THE REMAINDER OF THE EXTENDED....COLD WEATHER WILL CONTINUE INTO
THE END OF THE WORK WEEK AS HIGH PRESSURE AND ANOTHER SHOT OF COLD
AIR MOVE INTO THE REGION. MODELS HAVE BEEN ADVERTISING A PATTERN
SHIFT BY THE WEEKEND. LOOKS LIKE LONGWAVE PATTERN WILL PUSH ARCTIC
AIR BACK NORTH INTO CANADA AS THE NEXT WEATHER SYSTEM APPROACHING
THE REGION FROM THE WEST IS OF PACIFIC ORIGIN. TEMPERATURES WILL
MODERATE INTO THE WEEKEND WITH PERHAPS A THREAT OF SHOWERS IN THE
WAA PATTERN SATURDAY AFTERNOON OR NIGHT.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
FAST SW FLOW ALOFT WILL ALLOW THE CLOUDS TO THICKEN AND CIGS TO LOWER
THROUGHOUT THE NIGHT. MANY OF THE 12Z MODELS BROUGHT A H5
DISTURBANCE THROUGH TONIGHT...WHICH BROUGHT SOME LIGHT SNOW.
18Z RUN OF THE NAM AND LATEST RUNS OF THE RAP AND HRRR ARE SHOWING
A LOWER CHANCE OF THIS. HAVE BACKED OFF ANY PCPN MENTION TONIGHT
TO A VCSH.
CIGS WILL CONTINUE TO LOWER ON SUNDAY...BUT SHOULD STAY VFR
THROUGH THE PERIOD. IN THE 30 HOUR CVG TAF...AFT 00Z MONDAY BROUGHT
IN PREVAILING RAIN/SNOW MIX WITH MVFR CONDITIONS.
OUTLOOK...MVFR/IFR CEILINGS AND VISIBILITIES WITH SNOW ARE
POSSIBLE SUNDAY NIGHT INTO MONDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...HATZOS
NEAR TERM...HATZOS
SHORT TERM...HATZOS
LONG TERM...HICKMAN
AVIATION...SITES
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
200 AM EST FRI NOV 14 2014
.SYNOPSIS...
PROGRESSIVELY COLDER AIR WILL CONTINUE TO PUSH INTO THE
REGION...AND WILL LAST INTO NEXT WEEK. THIS PROLONGED SPELL OF
WELL BELOW NORMAL TEMPERATURES WILL BE ACCOMPANIED BY THE FIRST
SIGNIFICANT LAKE EFFECT SNOW OF THE SEASON ACROSS THE NORTHWEST
SNOWBELT.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
FRONTOGENETICALLY FORCED LGT SNOW THAT BROUGHT THE FIRST DUSTING
OF THE SEASON TO PARTS OF THE LOWER SUSQ VALLEY IS SHOWING THE
DWINDLING TREND THAT WAS ADVERTISED BY THE HRRR AS THE PARENT
UPPER JET STREAK LIFTS AWAY FROM THE REGION. LITTLE MORE THAN
FLURRIES LEFT AT 06Z AND RADAR TRENDS SUGGEST THOSE SHOULD END BY
08Z.
MAIN FOCUS FOR THE REST OF THE NIGHT WILL BE LAKE EFFECT SNOW
SHOWERS ACROSS THE NW MTNS. DIRECTIONAL SHEAR IN THE 0-3KM
LAYER...COMBINED WITH ARRIVAL OF DRY AIR AS DEPICTED BY SATL-
DERIVED PWATS...IS LEADING TO GENERALLY LIGHT AND DISORGANIZED LE
SNOW BANDS OVR NW PA. BLEND OF LATEST RAP/NAM QPF SUPPORTS ONLY
UP TO AN ADDITIONAL INCH BTWN 06Z-12Z ACROSS WARREN CO. MAY NEED
TO CANCEL CURRENT LAKE WARNING/ADVISORY OVR THE NW MTNS...AS
ADDITIONAL ACCUMS LATER TODAY ALSO APPEAR LIGHT.
EXPECT CLEARING SKIES EARLY THIS MORNING ACROSS THE SUSQ
VALLEY...AS WAVE OF LOW PRES OFF THE E COAST PUSHES AWAY.
HOWEVER...LAKE EFFECT STRATOCU WILL KEEP SKIES MCLDY ACROSS THE W
MTNS. TEMPS ON TRACK TO BOTTOM OUT FROM ARND 20F OVR THE HIGH
TERRAIN OF THE ALLEGHENIES...TO THE M/U20S OVR THE SUSQ VALLEY.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM SATURDAY/...
FAVORABLE LES SNOW PATTERN CONTINUES FOR THE NW MTNS...WITH
FREQUENT SNOW SHOWERS AND LIGHTER ACCUMS FOR THE NORTH-CENTRAL
MTNS AND LAURELS AS A BROAD AREA OF STEEP LOW TO MID LEVEL LAPSE
RATES AND POCKET OF -15 TO -20C AIR AT 700 MB TRAVERSES THE AREA.
VARIABLE CLOUDINESS WILL BE FOUND ACROSS THE CENTRAL MTNS WITH
FLURRIES AND ISOLATED TO SCTD SNOW SHOWERS THAT COULD BRIEFLY
WHITEN THE GROUND.
TEMPS WILL BE 12-15F BELOW NORMAL WITH MAXES RANGING FROM AROUND
30F ACROSS THE NRN AND WRN MTNS...TO THE L40S IN THE SE.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
COLD PATTERN WILL CONTINUE WITH WELL-BELOW AVERAGE TEMPERATURES
THROUGH MUCH OF NEXT WEEK...
ANOMALOUS UPPER LEVEL RIDGING CENTERED OVER THE YUKON/ALASKA WILL
SUSTAIN AND MAINTAIN A DEEP TROUGH AND UNSEASONABLY COLD AIRMASS
OVER THE AREA THROUGH THE END OF THE PERIOD. FORECAST CONFIDENCE
REMAINS VERY HIGH IN A PROLONGED STRETCH OF COLDER THAN NORMAL
TEMPERATURES.
THE SIGNIFICANT...LONG DURATION LAKE EFFECT SNOW EVENT OVER THE
NW SNOWBELT WILL WIND DOWN BY SATURDAY NIGHT...AS THE LOW LEVEL
FLOW BACKS TO THE WSW AND INVERSION HEIGHTS COLLAPSE UNDER
INCREASING SUBSIDENCE ASSOCIATED WITH SHORTWAVE RIDGE AND SFC
HIGH PRESSURE MIGRATING EWD FROM THE CENTRAL APPALACHIANS OFF THE
MID ATLANTIC COAST. IN MOST LOCATIONS...SATURDAY WILL BE COLD AND
DRY WITH DAYTIME TEMPERATURE DEPARTURES BETWEEN 10 AND 15 DEGREES
BELOW MID NOVEMBER CLIMATOLOGY.
MODELS SHOW A LEAD SHORTWAVE CROSSING THE ERN GREAT LAKES ON
EARLY SUNDAY WHICH COULD SPREAD SOME LIGHT RAIN/SNOW INTO THE
AREA. RELOADING CENTRAL US TROUGH BECOMES WELL ESTABLISHED BY 12Z
MONDAY WITH CORE OF NEGATIVE HEIGHT ANOMALIES APPROACHING -3 STD
OVER THE UPPER MIDWEST. THERE IS A BROAD CONSENSUS IN A BROAD AREA
OF PCPN BLOSSOMING OVER THE AREA ON MONDAY AS MOISTURE AND LIFT
BECOME ENHANCED EAST OF THE DEEP TROUGH ALONG SHARPENING FRONTAL
AXIS. PTYPES WILL REMAIN CHALLENGING BUT IT LOOKS LIKE ANOTHER
POSSIBLE MIX OR CHANGEOVER EVENT FOR AREAS EAST OF THE ALLEGHENY
FRONT. THAT SAID...THERE IS ENOUGH SUPPORT TO RAISE POPS INTO THE
LKLY RANGE FOR DAY 4.5/5.
AN EVEN COLDER SURGE OF MODIFIED ARCTIC AIR SEEMS POISED TO BLAST
INTO THE REGION BEHIND THIS SYSTEM ON TUESDAY AND PERSIST THRU THE
MIDDLE OF NEXT WEEK. THE OVERALL BROAD CYCLONIC FLOW PATTERN WILL
FAVOR LAKE EFFECT AND TERRAIN ENHANCED SNOW SHOWERS OVER THE NW
MTNS WITH COLD AND DRY CONDITIONS FROM THE CENTRAL RIDGES INTO THE
LWR SUSQ VLY.
&&
.AVIATION /07Z FRIDAY THROUGH TUESDAY/...
SNOW BANDS CONTINUE TO WEAKEN AS THE TROUGH SWINGS INTO THE
NORTHEAST OVERNIGHT. CIGS HAVE LIFTED AT BFD...THOUGH LAKE EFFECT
BANDS ARE FORMING AND MOVING ONSHORE. EXPECT CIGS AND VSBYS TO BE
REDUCED ONCE AGAIN. BFD SHOULD SEE PERIODS OF IFR THROUGH THE
EVENING AND INTO TOMORROW MORNING AS THE LAKE EFFECT FLOW SHOULD
REMAIN PERSISTENT THROUGH THIS TIMEFRAME.
KJST IS CURRENTLY IFR AND THE MOISTURE FROM THE UPSLOPE FLOW IN
THE ALEGHENNIES SHOULD KEEP IFR VSBYS AND CIGS THROUGH MOST OF THE
OVERNIGHT HOURS. SOME MOISTURE COULD GET CUT OFF BETWEEN 06Z TO
09Z BUT STRONGER MOISTURE MOVING ONSHORE SHOULD ONCE AGAIN ALLOW
FOR A DROP IN CIGS AND VSBYS BY 11Z. EXPECT CIGS AND VSBYS TO LIFT
TO MVFR BY MID MORNING...AND VFR BY MIDDAY.
IN BTWN...KUNV AND KAOO WILL EXPERIENCE OCNL MVFR CIGS TONIGHT.
ARRIVAL OF DRIER AIR MASS BEHIND THE FRONT LATE TONIGHT WILL
BRING RISING CIGS OVR MOST OF THE REGION ALONG AND SE OF A LINE
FROM KAOO TO KELM.
OUTLOOK...
FRI...PM SNOW SHOWERS/REDUCED VSBYS POSS AT KBFD AND JST.
SAT...AM SNOW SHOWERS/REDUCED VSBYS POSS AT KBFD AND JST.
SUN...SNOW SHOWERS/REDUCED VSBYS POSS AT KBFD.
MON...LGT SNOW/LOW CIGS POSS NW HALF OF PA. RAIN/LOW CIGS POSS SE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST THIS EVENING FOR
PAZ005.
LAKE EFFECT SNOW WARNING UNTIL 7 PM EST THIS EVENING FOR
PAZ004.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...FITZGERALD
SHORT TERM...FITZGERALD/LAMBERT
LONG TERM...STEINBUGL
AVIATION...LAMBERT/CERU
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1208 AM EST FRI NOV 14 2014
.SYNOPSIS...
PROGRESSIVELY COLDER AIR WILL CONTINUE TO PUSH INTO THE
REGION...AND WILL LAST INTO NEXT WEEK. THIS PROLONGED SPELL OF
WELL BELOW NORMAL TEMPERATURES WILL BE ACCOMPANIED BY THE FIRST
SIGNIFICANT LAKE EFFECT SNOW OF THE SEASON ACROSS THE NORTHWEST
SNOWBELT.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
FRONTOGENETICALLY FORCED SNOW/RAIN THAT BROUGHT A COATING OF SNOW
TO SOME GRASSY SURFACES OVER THE LOWER SUSQ VALLEY IS SHOWING THE
DWINDLING TREND THAT WAS ADVERTISED BY THE HRRR AS THE PARENT
UPPER JET STREAK LIFTS AWAY FROM THE REGION. LITTLE MORE THAN A
FEW LINGERING LIGHT SNOW/RAIN SHOWERS AND SOME FLURRIES ARE LEFT
BEHIND OVER CENTRAL AND EASTERN AREAS.
FURTHER TO OUR NW...BANDED LAKE EFFECT IS STARTING TO ORGANIZE BUT
IT HAS BEEN SLOW. THIS WILL BECOME THE MAIN MODE OF PRECIP THAT
WE WILL BE DEALING WITH FOR THE NEXT 24-36 HOURS AS THE WINDS
BECOME BETTER ALIGNED OVERNIGHT INTO FRIDAY.
WE ARE CONTINUING THE LAKE EFFECT SNOW WARNING THROUGH 00Z SAT
FOR WARREN COUNTY...AND THE LAKE EFFECT SNOW ADVISORY ACROSS
MCKEAN COUNTY THROUGH THE SAME PERIOD.
FROM EARLIER...
PERSISTENT LIGHT TO MDT...NWRLY BOUNDARY LAYER FLOW /COUPLED WITH
DEEP COLD AIR AND NEARLY A 20C LAKE-850 MB T DIFF...ALONG WITH
THE LONG DURATION OF THIS LES EVENT/ LOOKS VERY FAVORABLE FOR
HEAVY SNOW AMOUNTS ACROSS THE PERENNIAL SNOWBELT OF NW WARREN
COUNTY WHERE OVER 1 FOOT LOOKS POSSIBLE BY FRIDAY NIGHT...WITH
SOME ADDITIONAL ACCUMS LIKELY HEADING INTO SATURDAY.
THE MEAN WIND IN THE LAYER STEERING THE LAKE EFFECT BANDS WILL
VARY BY ABOUT 30 DEG FROM 285-315 DEG TONIGHT INTO FRIDAY...WITH
EVEN SOME PULSES OF DRIER AIR CREATING A FEW LULLS IN THE ACTION.
STILL...IT`S BEST AT THIS POINT TO PLACE THIS EVENT INTO ONE LONG
PACKAGE AND PROVIDE PLENTY OF LEAD TIME FOR THIS FIRST SIGNIFICANT
LES EVENT.
THE REST OF THE NW MTNS OUTSIDE OF THE LES ADVISORY DOWN THRU THE
LAURELS WILL SEE ACCUMULATING SNOW ON THE ORDER OF A FEW TO SVRL
INCHES BY THE TIME ITS ALL OVER SATURDAY. HOWEVER...AMOUNTS IN
ANY ONE GIVEN 12-24 HOUR PERIOD WON`T REALLY ADD UP TO ADVISORY
AMOUNTS. THE EXCEPTION MAY BE ON THE WEST FACING SLOPES OF THE
LAURELS SKI COUNTRY WHERE 6 TO 8 INCHES IS POSSIBLE BY 12Z
SATURDAY.
AFTER THE PASSAGE OF THE COASTAL LOW LOW LATER TONIGHT...CLOUD
BASES WITH LIFT ACROSS THE CENTRAL MTNS AND SUSQ VALLEY WITH
FLURRIES AND ISOLATED SNOW SHOWERS.
LOWS TONIGHT WILL VARY FROM THE L20S ACROSS THE NRN AND WRN
MTNS...TO THE MID AND UPPER 20S IN THE SE.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/...
FAVORABLE LES SNOW PATTERN CONTINUES FOR THE NW MTNS...WITH
FREQUENT SNOW SHOWERS AND LIGHTER ACCUMS FOR THE NORTH-CENTRAL
MTNS AND LAURELS AS A BROAD AREA OF STEEP LOW TO MID LEVEL LAPSE
RATES AND POCKET OF -15 TO -20C AIR AT 700 MB TRAVERSES THE AREA.
VARIABLE CLOUDINESS WILL BE FOUND ACROSS THE CENTRAL MTNS WITH
FLURRIES AND ISOLATED TO SCTD SNOW SHOWERS THAT COULD BRIEFLY
WHITEN THE GROUND.
TEMPS WILL BE 12-15F BELOW NORMAL WITH MAXES RANGING FROM AROUND
30F ACROSS THE NRN AND WRN MTNS...TO THE L40S IN THE SE.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
COLD PATTERN WILL CONTINUE WITH WELL-BELOW AVERAGE TEMPERATURES
THROUGH MUCH OF NEXT WEEK...
ANOMALOUS UPPER LEVEL RIDGING CENTERED OVER THE YUKON/ALASKA WILL
SUSTAIN AND MAINTAIN A DEEP TROUGH AND UNSEASONABLY COLD AIRMASS
OVER THE AREA THROUGH THE END OF THE PERIOD. FORECAST CONFIDENCE
REMAINS VERY HIGH IN A PROLONGED STRETCH OF COLDER THAN NORMAL
TEMPERATURES.
THE SIGNIFICANT...LONG DURATION LAKE EFFECT SNOW EVENT OVER THE
NW SNOWBELT WILL WIND DOWN BY SATURDAY NIGHT...AS THE LOW LEVEL
FLOW BACKS TO THE WSW AND INVERSION HEIGHTS COLLAPSE UNDER
INCREASING SUBSIDENCE ASSOCIATED WITH SHORTWAVE RIDGE AND SFC
HIGH PRESSURE MIGRATING EWD FROM THE CENTRAL APPALACHIANS OFF THE
MID ATLANTIC COAST. IN MOST LOCATIONS...SATURDAY WILL BE COLD AND
DRY WITH DAYTIME TEMPERATURE DEPARTURES BETWEEN 10 AND 15 DEGREES
BELOW MID NOVEMBER CLIMATOLOGY.
MODELS SHOW A LEAD SHORTWAVE CROSSING THE ERN GREAT LAKES ON
EARLY SUNDAY WHICH COULD SPREAD SOME LIGHT RAIN/SNOW INTO THE
AREA. RELOADING CENTRAL US TROUGH BECOMES WELL ESTABLISHED BY 12Z
MONDAY WITH CORE OF NEGATIVE HEIGHT ANOMALIES APPROACHING -3 STD
OVER THE UPPER MIDWEST. THERE IS A BROAD CONSENSUS IN A BROAD AREA
OF PCPN BLOSSOMING OVER THE AREA ON MONDAY AS MOISTURE AND LIFT
BECOME ENHANCED EAST OF THE DEEP TROUGH ALONG SHARPENING FRONTAL
AXIS. PTYPES WILL REMAIN CHALLENGING BUT IT LOOKS LIKE ANOTHER
POSSIBLE MIX OR CHANGEOVER EVENT FOR AREAS EAST OF THE ALLEGHENY
FRONT. THAT SAID...THERE IS ENOUGH SUPPORT TO RAISE POPS INTO THE
LKLY RANGE FOR DAY 4.5/5.
AN EVEN COLDER SURGE OF MODIFIED ARCTIC AIR SEEMS POISED TO BLAST
INTO THE REGION BEHIND THIS SYSTEM ON TUESDAY AND PERSIST THRU THE
MIDDLE OF NEXT WEEK. THE OVERALL BROAD CYCLONIC FLOW PATTERN WILL
FAVOR LAKE EFFECT AND TERRAIN ENHANCED SNOW SHOWERS OVER THE NW
MTNS WITH COLD AND DRY CONDITIONS FROM THE CENTRAL RIDGES INTO THE
LWR SUSQ VLY.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
SNOW BANDS CONTINUE TO WEAKEN AS THE TROUGH SWINGS INTO THE
NORTHEAST OVERNIGHT. CIGS HAVE LIFTED AT BFD...THOUGH LAKE EFFECT
BANDS ARE FORMING AND MOVING ONSHORE. EXPECT CIGS AND VSBYS TO BE
REDUCED ONCE AGAIN. BFD SHOULD SEE PERIODS OF IFR THROUGH THE
EVENING AND INTO TOMORROW MORNING AS THE LAKE EFFECT FLOW SHOULD
REMAIN PERSISTENT THROUGH THIS TIMEFRAME.
KJST IS CURRENTLY IFR AND THE MOISTURE FROM THE UPSLOPE FLOW IN
THE ALEGHENNIES SHOULD KEEP IFR VSBYS AND CIGS THROUGH MOST OF THE
OVERNIGHT HOURS. SOME MOISTURE COULD GET CUT OFF BETWEEN 06Z TO
09Z BUT STRONGER MOISTURE MOVING ONSHORE SHOULD ONCE AGAIN ALLOW
FOR A DROP IN CIGS AND VSBYS BY 11Z. EXPECT CIGS AND VSBYS TO LIFT
TO MVFR BY MID MORNING...AND VFR BY MIDDAY.
IN BTWN...KUNV AND KAOO WILL EXPERIENCE OCNL MVFR CIGS TONIGHT.
ARRIVAL OF DRIER AIR MASS BEHIND THE FRONT LATE TONIGHT WILL
BRING RISING CIGS OVR MOST OF THE REGION ALONG AND SE OF A LINE
FROM KAOO TO KELM.
OUTLOOK...
FRI...PM SNOW SHOWERS/REDUCED VSBYS POSS AT KBFD AND JST.
SAT...AM SNOW SHOWERS/REDUCED VSBYS POSS AT KBFD AND JST.
SUN...SNOW SHOWERS/REDUCED VSBYS POSS AT KBFD.
MON...LGT SNOW/LOW CIGS POSS NW HALF OF PA. RAIN/LOW CIGS POSS SE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST FRIDAY FOR PAZ005.
LAKE EFFECT SNOW WARNING UNTIL 7 PM EST FRIDAY FOR PAZ004.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...LAMBERT
LONG TERM...STEINBUGL
AVIATION...LAMBERT/CERU
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
625 PM CST SAT NOV 15 2014
.UPDATE...
LATEST RADAR IMAGERY AND REPORTS IN THE PAH AREA INDICATE A MIX OF
LIGHT RAIN AND LIGHT SLEET IS SKIMMING OUR FAR NORTHWEST COUNTIES.
ANOTHER MORE EXPANSIVE BAND OF LIGHT RAIN AND LIGHT SLEET IS
MOVING RAPIDLY EASTWARD ACROSS NORTHERN ARKANSAS...AND THIS
ACTIVITY WILL MOVE INTO AND ACROSS OUR NORTHWEST COUNTIES LATE
THIS EVENING AND OVERNIGHT PER LATEST HRRR RUNS. HAVE ADDED
SLIGHT CHANCE POPS FOR A POTENTIAL MIX OF LIGHT RAIN AND LIGHT
SLEET THIS EVENING OVER THE NORTHWEST...AND OVER THE WESTERN TWO-
THIRDS OF THE CWA AFTER MIDNIGHT. NO SLEET ACCUM IS EXPECTED AS
TEMPS WILL REMAIN WELL ABOVE FREEZING. EXTENSIVE LOW CLOUDS HAVE
ALSO BEGUN SPREADING INTO THE FORECAST AREA AND SHOULD QUICKLY
BLANKET THE MID STATE BY EARLY MORNING...AND MADE ADJUSTMENTS TO
CLOUD COVER BASED ON CURRENT SATELLITE IMAGERY. IN
ADDITION...CURRENT LOW TEMPS ARE LIKELY TOO COOL BASED ON THIS
CLOUD COVER AND HAVE RAISED THEM A COUPLE DEGREES AREAWIDE. REST
OF FORECAST IS ON TRACK.
SHAMBURGER
&&
.PREV DISCUSSION... /ISSUED 326 PM CST SAT NOV 15 2014/
DISCUSSION...
SFC LOW BEGINNING TO DEVELOP OFF OF THE SE TX COAST THIS AFTERNOON.
CURRENT ACTIVITY...MOSTLY SNOWFALL... IS OCCURRING ACROSS
MO...NORTHWARD INTO MN. THIS IS IN RESPONSE TO LOW PRESSURE OVER
WESTERN TX WITH A COLD FRONT EXTENDING NORTHWARD THROUGH THE CENTRAL
AND NORTHERN PLAINS. MOSTLY CLOUDY SKIES ARE NOW COMMONPLACE FROM
NRN AR NORTHWARD AND EASTWARD.
THE SFC HIGH WHICH BROUGHT THE COLDER WEATHER TO MIDDLE TN HAS NOW
MOVED EAST AND IS CENTERED OVER THE MID ATLANTIC STATES. TEMPS ARE
WARMER TODAY WITH AFTERNOON READINGS NOW IN THE 40S AT MOST
LOCATIONS.
GOING FORWARD...SFC TROUGH INVERSION TO BEGIN DEVELOPING TONIGHT AND
ESPECIALLY ON SUNDAY. THE AXIAL POSITIONING IS SLIGHTLY FURTHER WEST
THAN PREVIOUS MODEL RUNS. SO...AS THE MAIN LOW TRACKS NE ALONG THE
AXIS...TEMPERATURES WILL BE A TOUCH WARMER THAN PREVIOUSLY
THOUGHT. SO...ALTHOUGH WE STILL EXPECTED SOME SNOW ON THE BACK
EDGE OF THE MOISTURE LATE SUNDAY NIGHT...ACCUMULATION POTENTIAL
STILL LOOKS MINOR. GFS IS STILL THE COLDEST OF THE MODELS BUT THE
CONSALL SUPPORTS THE FACT THAT THE GFS MAY BE A LITTLE TOO COLD.
SO...FOR THE FCST...PERHAPS A SLIGHT SLEET/RAIN MIX LATE TONIGHT BUT
LOWER LEVELS ARE VERY DRY AND AMOUNTS WILL BE INCONSEQUENTIAL. ON
SUNDAY...A SLEET AND RAIN MIX IS POSSIBLE EARLY BEFORE THE
PRECIPITATION ALL CHANGES TO RAIN. RAIN WILL CONTINUE INTO SUNDAY
EVENING. THEN...AFTER MIDNIGHT...THE SFC LOW WILL BE MOVING ACROSS
NRN GA AND CAA WILL PICK UP ACROSS THE MID STATE. IT IS AT THAT TIME
THAT THE RAINFALL WILL BEGIN TO CHANGEOVER TO SNOW IN OUR FAR
NORTHWEST. THE POSITIONING OF THE BACK EDGE OF THE DEEPER MOISTURE
IN CONJUNCTION WITH THE SUB ZERO 850 MB TEMPS WILL BE SHRINKING IN
AREAL COVERAGE AS THE MOISTURE PULLS EAST. THEREFORE...ANY SNOW
ACCUMULATION TOTAL CHANCES WILL BE GREATEST OVER FAR NORTHERN AND
OVER WESTERN AREAS PRIMARILY. BUT...A CHANGEOVER TO SNOW WILL
STILL BE POSSIBLE ACROSS THE ENTIRE AREA LATE SUNDAY NIGHT AND
MONDAY MORNING. ACCUMULATIONS OF AROUND AN INCH ARE POSSIBLE
ACROSS NORTHWESTERN AND FAR NORTHERN AREAS...LESSER AMOUNTS AS YOU
MOVE EASTWARD AND SOUTHWARD. OFFICIAL GRIDS SHOW NO SNOW
ACCUMULATION FOR SOUTHERN AREAS. AS THE DEPTH OF THE COLD AIR
BEGINS TO INCREASE...THERE COULD BE AN INITIAL PERIOD OF SLEET
PRIOR TO THE CHANGEOVER TO SNOW.
OVERNIGHT LOWS SUNDAY NIGHT WILL RANGE FROM THE UPPER 20S FAR NW TO
THE MID 30S ACROSS SOUTHERN MIDDLE TN.
ON MONDAY...THE COLD AIR WILL BEGIN TO POUR IN. 850 MB TEMPS WILL
DROP TO NEAR -15C BY 00Z TUES. THE GFS DOES HINT TOWARD A WEAK
IMPULSE THAT AFTERNOON. WILL THEREFORE INCLUDE A SLIGHT CHANCE OF
FLURRIES. OTW...TEMPS BY LATE MONDAY AFTERNOON WILL RANGE FROM THE
UPPER 20S NORTH TO THE LOWER 30S SOUTH. VERY COLD TEMPS WILL FOLLOW
THIS FOR WEDNESDAY AS WELL.
IN THE EXT FCST...THERMAL TROUGH WILL PULL EAST WITH MODERATING
TEMPS TOWARD THE END OF THE WEEK. SOME MOISTURE LATE IN THE WEEK IS
EXPECTED TO RETURN. MODELS NOT IN VERY GOOD AGREEMENT SO WILL KEEP
POPS LOW. IT DOES HOWEVER...LOOK LIKE A RAIN ONLY PATTERN. CONSALL
GUIDANCE SUPPORTS THE WARMER MINS. FURTHERMORE...REGARDLESS OF WHAT
MODEL YOU CHOOSE...THE TEMP MOISTURE CONNECTION SUPPORTS RAIN ONLY.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
55
FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
948 PM EST SAT NOV 15 2014
.SYNOPSIS...
HIGH PRESSURE WILL SLIDE OFF THE EAST COAST TONIGHT WHILE A STORM
SYSTEM ORGANIZES TO OUR SOUTHWEST ON SUNDAY AND BRINGS RAINFALL
TO THE AREA INTO THE DAY MONDAY. ARCTIC AIR WILL FOLLOW THIS
SYSTEM MONDAY NIGHT INTO MIDWEEK WITH STRONG WINDS AND VERY COLD
TEMPERATURES.
&&
.NEAR TERM /THROUGH SUNDAY/...
AS OF 945 PM EST SATURDAY...
FORECAST PERIOD WILL FEATURE A RETREATING AREA OF SURFACE HIGH
PRESSURE TONIGHT AND ON SUNDAY WITH WARM AIR ADVECTION AND
SOUTHWESTERLY FLOW BRINGING MILDER TEMPS AND INCREASING CLOUDS.
MINOR ADJUSTMENT TO OVERNIGHT LOWS BASED ON CURRENT TEMPERATURE
AND CLOUD COVER TRENDS. LATEST LOCAL WRF AND HRRR GUIDANCE KEEP
PRECIPITATION THAT WAS SPREADING INTO THE OHIO VALLEY TO THE
NORTHWEST OF THE FORECAST AREA THROUGH AT LEAST 12Z/7AM.
CLOUDS CONTINUE TO INCREASE ON SUNDAY AS AN AREA OF LOW PRESSURE
BEGINS TO DEVELOP ALONG THE GULF COAST/LOWER MISSISSIPPI VALLEY IN
RESPONSE TO A DIGGING SOUTHERN STREAM SHORTWAVE EMERGING FROM THE
TROUGH OVER THE SOUTHERN ROCKIES/WESTERN HIGH PLAINS. A BROAD AREA
OF OVERRUNNING PRECIPITATION WILL RACE NORTHEASTWARD THROUGH THE
LOWER TENNESSEE VALLEY DURING THE DAY REACHING OUR WESTERN
FORECAST AREA BY EARLY EVENING.
HIGHS TOMORROW MID-40S TO NEAR 50 AS THE LOWERING/THICKENING
CLOUD COVER OFFSETS WARM ADVECTION. H85 TEMPS +4 TO +7C RANGE BY
00Z MONDAY AS THE PRECIP BEGINS TO ARRIVE WHICH SHOULD ENSURE AN
ALL-LIQUID EVENT FROM THE ONSET... ALTHOUGH VERY BRIEF PERIOD OF
SLEET IN A FEW SHELTERED VALLEYS MAY BE POSSIBLE DUE TO SOME QUICK
EVAPORATIONAL COOLING.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
AS OF 300 PM EDT SATURDAY...
A NORTHERN STREAM TROUGH WILL DROP SOUTH OVER THE PLAINS SUNDAY.
THE NORTHERN STREAM WILL BEGIN TO PHASE WITH THE SOUTHERN STREAM
SUNDAY NIGHT...GENERATING A SURFACE WAVE NEAR THE MOUTH OF THE
MISSISSIPPI RIVER. THIS WAVE WILL THEN TRACK INLAND TOWARDS THE
SOUTHERN APPALACHIAN MOUNTAINS MONDAY MORNING...THEN TO THE NEW
ENGLAND COAST MONDAY EVENING. A COLD FRONT WILL SWEEP ACROSS THE
REGION MONDAY NIGHT. THE UPPER LEVEL TROUGH WILL ACROSS THE OHIO
VALLEY INTO THE MID ATLANTIC REGION TUESDAY.
STORM CONCERNS WILL BE P-TYPE AND AMOUNTS. WARM AIR WILL PUSH
INTO THE REGION AS THIS LOW TRACKS FROM THE GULF COAST SUNDAY
EVENING TO THE MID ATLANTIC MONDAY AFTERNOON. TEMPERATURES AND
THICKNESSES WARM ENOUGH TO HAVE MOSTLY A RAIN EVENT. BY THE TIME
THE COLD AIR ENTERS THE FORECAST AREA LATE MONDAY
AFTERNOON...MOISTURE ASSOCIATED WITH THE SURFACE LOW WILL EXIT THE
REGION. MOISTURE AND COLD AIR AHEAD OF THE UPPER LEVEL TROUGH WILL
THEN BRING MOUNTAIN SNOW SHOWERS AND FLURRIES MONDAY NIGHT INTO
TUESDAY. ACCUMULATIONS PRIMARILY ALONG WESTERN SLOPES WITH
FLURRIES ELSEWHERE TO THE BLUE RIDGE. ACCUMULATIONS UP TO 3 INCHES
LIKELY ALONG WESTERN SLOPES OF SOUTHEASTERN WEST VIRGINIA.
INITIAL PRECIPITATION MAY HAVE P-TYPE CONCERNS AS RESIDUAL INSITU
WEDGE MAY LINGER OVER THE FOOTHILLS AND PIEDMONT COUNTIES INTO
SUNDAY EVENING. RAIN FALLING INTO THIS DRY AIR MAY EXPERIENCE
EVAPORATIVE COOLING AND BRIEFLY FALL AS SLEET...ESPECIALLY IF RAIN
DOES NOT START TO FALL UNTIL THE EVENING HOURS. IF RAIN ADVANCES
OVER AN AREA DURING THE AFTERNOON...THEN PRECIPITATION WILL REMAIN
AS RAIN UNTIL THE FRONT PASSES EAST.
ANOTHER CONCERN WILL FOLLOW BEHIND THE FRONT. PRESSURE RISES AND
AN INCREASING NORTHWEST CROSS BARRIER FLOW WILL BRING WINDY AND
GUSTY CONDITIONS TO THE AREA. WIND GUSTS UP TO 45 MPH ARE POSSIBLE
ALONG RIDGETOPS...ESPECIALLY ALONG THE BLUE RIDGE. A TIGHT
PRESSURE GRADIENTS WILL REMAIN OVER THE REGION INTO TUESDAY. WIND
CHILL VALUES ACROSS THE MOUNTAINS TUESDAY MORNING MAYBE AROUND
ZERO.
TEMPERATURES MONDAY WILL VARY GREATLY FROM THE MID 40S OVER THE
MOUNTAINS TO THE 50S IN THE EAST. MOUNTAIN TEMPERATURES MAY PEAK
EARLY...POSSIBLY FALLING IN THE AFTERNOON DEPENDING ON THE TIMING
OF THE FRONTAL PASSAGE. TEMPERATURES MONDAY NIGHT WILL DROP OFF
DRAMATICALLY AS ARCTIC AIR RUSHES IN. MORNING LOWS ACROSS THE
MOUNTAINS WILL RANGE FROM 10F-20F TO 20F-30F EAST. NOT MUCH OF A
WARMUP ON TUESDAY WITH MOUNTAINS LOCATIONS NOT MAKING IT ABOVE
FREEZING AND IN THE EAST PEAKING OUT IN THE 30S.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 230 PM EST SATURDAY...
A WARM FRONT WILL PASS OVER THE REGION WEDNESDAY...BUT AFTERNOON
TEMPERATURES WILL REMAIN 20F COLDER THAN NORMAL. MORE WARMING ON
THURSDAY WHILE TEMPERATURES REMAIN 10F COLDER THAN NORMAL. A DRY
COLD FRONT WILL TRACK ACROSS THE REGION THURSDAY EVENING.
TEMPERATURES WILL COOL SOME...BUT NOTHING LIKE THE CURRENT COLD
SPELL WE ARE EXPERIENCING THIS WEEKEND. HIGH PRESSURE WILL THEN
KEEP THE AREA DRY INTO SATURDAY.
&&
.AVIATION /03Z SUNDAY THROUGH THURSDAY/...
AS OF 635 PM EST SATURDAY...
SURFACE HIGH PRESSURE WAS OVER EASTERN VIRGINIA THIS EVENING. LOW
PRESSURE WILL DEVELOP ALONG THE SOUTHEAST COAST AS THE HIGH MOVES
OFFSHORE. A STRONGER LOW PRESSURE SYSTEM WILL CROSS THE SOUTHERN
PLAINS TONIGHT AND SUNDAY. CLOUDS WILL FILL IN ACROSS THE FORECAST
AREA OVERNIGHT. HIGH CONFIDENCE THAT CEILINGS WILL REMAIN VFR.
THERE IS A CHANCE OF LIGHT RAIN AT KLWB AND KBLF AFTER 21Z/4PM
SUNDAY.
AS LOW PRESSURE DEVELOPS ALONG THE COAST...LOW CLOUDS WILL SPREAD
NORTH THROUGH THE CAROLINAS AND INTO VIRGINIA. LOWER CLOUDS...BUT
STILL VFR THROUGH 00Z MONDAY...MAY REACH KDAN SUNDAY AFTERNOON.
EXTENDED DISCUSSION...
THE SOUTHERN PLAINS LOW WILL TRACK THROUGH THE TENNESSEE VALLEY BY
MONDAY MORNING AND INTO SOUTHEAST CANADA BY TUESDAY MORNING. RAIN
WILL BECOME WIDESPREAD ACROSS THE AREA BY LATE SUNDAY NIGHT. SOME
IP/SN POSSIBLE AT THE ONSET. AS THIS SYSTEM MOVES NORTHEAST
SHOULD SEE CIGS/VSBYS SINK TO IFR/MVFR AT ALL TAF SITES MONDAY
WITH THE POTENTIAL FOR LOWER CEILINGS IN THE MTNS.
THE COLD FRONT MOVES ACROSS FOR MONDAY AFTERNOON/NIGHT WITH NW
FLOW WORKING MUCH COLDER AIR IN AGAIN...WITH RAIN CHANGING TO
SNOW SHOWERS OVER THE MOUNTAINS...WHILE THE PIEDMONT/FOOTHILLS DRY
OUT. GUSTY WINDS WILL CREATE TURBULENT FLYING CONDITIONS MON NIGHT
AND TUESDAY WITH WIND GUSTS UP TO 40 KNOTS POSSIBLE. VFR EAST AND
STAYING MVFR/IFR IN THE MTNS TIL LATER TUESDAY.
HIGH PRESSURE OVER THE GULF COAST STATES THEN BUILDS EAST ACROSS
THE AREA BY TUESDAY NIGHT WITH VFR CONDITIONS AND DIMINISHING WIND.
&&
.HYDROLOGY...
AS OF 250 PM EST SATURDAY...
FORECAST PRECIPITATION FOR THE UPCOMING EVENT RANGES FROM ABOUT
ONE-HALF /0.50/ INCH OVER THE NORTHERN RIVER BASINS UP TO ABOUT
ONE /1.00/ INCH OVER THE SOUTHERN RIVER BASINS BY THE TIME IT ENDS
LATE MONDAY. THE RAINFALL IS NEEDED AS PRECIPITATION IN NOVEMBER
TO DATE HAS BEEN VERY SCANTY. MOST OF THE COOP NETWORK SITES HAVE
RECEIVED UNDER 0.50 INCHES FOR THE MONTH AND SOME LESS THAN 0.25
INCHES. A SUBSTANTIAL PORTION OF THE PIEDMONT IN OUR CWA IS
ALREADY IN THE ABNORMALLY DRY CATEGORY ON THE WEEKLY U.S. DROUGHT
MONITOR WITH RAINFALL DEFICITS OF 2 TO 4 INCHES OVER THE PAST 60
DAYS. THE DRY PERIOD IS REFLECTED IN DECLINING STREAM FLOWS AS
MONITORED BY THE USGS STREAM GAGING NETWORK AND ALSO BY FALLING
RESERVOIR STORAGE.
&&
.EQUIPMENT...
AS OF 645 PM EST SATURDAY...
THE VISIBILITY SENSOR AT KLYH...LYNCHBURG AIRPORT...WILL BE OUT
OF SERVICE UNTIL MONDAY WHEN TECHNICHIANS WILL REPLACE THE
SENSOR. UNTIL THEN THE VISIBILITY WILL ONLY BE REPORTED WHEN THE
CONTROL TOWER IS STAFFED.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...PC
NEAR TERM...PC/AMS
SHORT TERM...RCS
LONG TERM...RCS
AVIATION...AMS/PC
HYDROLOGY...PC
EQUIPMENT...AMS
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1157 PM EST THU NOV 13 2014
.SYNOPSIS...
LOW PRESSURE WAS OFF THE MID ATLANTIC COAST TONIGHT AND WILL DEEPEN
OFF THE NEW ENGLAND COAST ON FRIDAY. ARCTIC HIGH PRESSURE WILL
BUILD INTO THE REGION INTO SATURDAY. OUR NEXT POTENTIAL WEATHER
MAKER MOVES ACROSS THE AREA SUNDAY THROUGH MONDAY WITH GUSTY WINDS
AND COLD TEMPERATURES BEHIND IT ON TUESDAY.
&&
.NEAR TERM /THROUGH FRIDAY/...
AS OF 1035 PM EST THURSDAY...
THE WATER VAPOR LOOP SHOWED A SHORT WAVE CROSSING INTO EASTERN
VIRGINIA. THE BETTER AREAL COVERAGE OF RAIN WAS MOVING EAST WITH
THIS WAVE. LAST FEW RUNS OF THE HRRR HAD A MAJORITY OF THIS
PRECIPITATION EAST OF THE FORECAST AREA BY 08Z/3AM.
ANOTHER ELONGATED SHORT WAVE WAS OVER PENNSYLVANIA AND WEST
VIRGINIA. SCATTERED SNOW SHOWERS ASSOCIATED WITH THIS FEATURE
WERE MOVING ACROSS EASTERN SECTIONS OF WEST VIRGINIA.
MSAS ANALYSIS SHOWED PRESSURE FALLS AND A DEEPENING LOW WELL OFF
THE DELMARVA PENINSULA. AS THIS LOW CONTINUES TO STRENGTHEN...THE
MAGNITUDE OF THE NORTHWEST FLOW COLD AIR ADVECTION INCREASES
TONIGHT AND THIS WILL BE THE TIME WHERE OUR REALLY GOOD SURGE OF
COLDER AIR COMMENCES ACROSS THE REGION. LOWS TONIGHT WILL RANGE
FROM THE UPPER TEENS TO LOWER 20S ACROSS THE MOUNTAINS WITH UPPER
20S TO LOWER 30S ACROSS THE PIEDMONT.
ON FRIDAY...NORTHWEST FLOW WILL CONTINUE AND HELP MAINTAIN UPSLOPE
CLOUDS ACROSS THE MOUNTAINS THROUGH AT LEAST MIDDAY. IN THE
EAST...THE CLOUD COVER WILL CLEAR EARLY GIVEN A DECENT DOWNSLOPE
COMPONENT. DRIER AIR WILL EVENTUALLY WIN OUT IN THE MOUNTAINS
TOO...WITH MOST REGIONS AT LEAST MOSTLY SUNNY BY THE LATE AFTERNOON.
HIGH TEMPERATURES WILL RANGE FROM THE LOW TO MID 30S ACROSS THE
MOUNTAINS WITH READINGS AROUND 40 TO THE LOWER 40S ACROSS THE
PIEDMONT. SOME OF THE FORECAST HIGHS...ESPECIALLY THOSE IN THE
WEST...ARE ONLY EXPECTED TO BE A COUPLE OF DEGREES ABOVE THE RECORD
LOW MAXIMUMS FOR THE DAY. SPECIFIC LOW MAXIMUM RECORDS FOR FRIDAY
AND SATURDAY ARE IN THE CLIMATE SECTION OF THIS DISCUSSION.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY NIGHT/...
AS OF 205 PM EST THURSDAY...
COLD HIGH PRESSURE WILL SLIDE EAST ACROSS THE AREA FRIDAY NIGHT AND
BE ABOUT OVERHEAD BY SATURDAY MORNING. THIS WILL BRING CLEAR SKIES
UNDER STRONG SUBSIDENCE ALONG WITH VERY COLD EARLY MORNING TEMPS
SATURDAY AS THE CORE OF THE COLDEST 85H SETTLES OVERHEAD. THIS ALONG
WITH GREAT RADIATIONAL COOLING SUPPORTS LOWS IN THE TEENS WEST TO
LOW/MID 20S EAST. RIDGING SHIFTS SLOWLY EAST DURING SATURDAY BUT
SHOULD HANG ON LONG ENOUGH TO KEEP THINGS MOSTLY SUNNY BUT STILL ON
THE COLD SIDE WITH ONLY ABOUT A 3-5+ DEGREE RISE IN 85H TEMPS.
HOWEVER EVEN WITH SOME SLIGHT WARMING ALOFT INFLUX OF HIGH LEVEL
CLOUDS MAY HOLD TEMPS SLIGHTLY BELOW MOS...MAINLY 38-45.
MID LEVEL RIDGING STARTS TO BREAK DOWN SATURDAY NIGHT INTO SUNDAY AS
A DEVELOPING 5H TROUGH STARTS TO APPROACH FROM THE WEST. ONSET OF
BETTER MID/HIGH LEVEL MOISTURE LIKELY TO BRING INCREASING CLOUDS
SATURDAY NIGHT BUT LIKELY THIN ENOUGH EARLY ON TO ALLOW TEMPS TO DIP
INTO THE 20S MOST SPOTS BUT STILL DRY. SYSTEM HEADS EAST TOWARD THE
REGION BUT QUITE DISORGANIZED INITIALLY WITH NORTHERN STREAM ENERGY
PASSING TO THE NW AND THE MAIN SOUTHERN STREAM WAVE STILL HANGING
BACK ALONG THE GULF COAST. SOME SOLUTIONS SUCH AS THE GFS REMAIN
FAST TO BRING SOME LEAD LIGHT PRECIP NE INTO THE AREA ON SUNDAY
WHILE OTHERS PER THE LATEST ECMWF QUITE SLOW WITH LITTLE PRECIP AT
ALL DURING THE DAY. GIVEN THE STRONG UPPER JET AND PAST HISTORY OF
WEAK LIFT SYSTEMS DEVELOPING PRECIP FASTER...LEFT IN SOME CHANCE
POPS SUNDAY AFTERNOON WITH SOME LIGHT SNOW...MAINLY FAR NW WHERE A
NAM/GFS MIX WOULD SUPPORT A MORE FROZEN SCENARIO. TEMPS TO WARM A
BIT UNDER WARM ADVECTION ALOFT IN ADVANCE OF THE INITIAL FRONT WITH
HIGHS MOSTLY 40S EXCEPT LOW 50S SE.
DIGGING/AMPLIFYING 5H TROUGH WILL START TO ARRIVE FROM THE NW LATER
SUNDAY NIGHT AND HELP ENHANCE MOISTURE COMING NE WITH THE SOUTHERN
SHORTWAVE. HOWEVER JUST HOW FAST THIS HAPPENS KEY TO PRECIP COVERAGE
SUNDAY NIGHT AS WELL AS THE TEMP PROFILE ALOFT GIVEN DECENT 85H WARM
ADVECTION. LATEST GFS FASTER BUT STILL HAS BEST LIFT CLOSER TO THE
BAROCLINIC ZONE ALONG THE APPALACHIANS AS WEAK SURFACE WAVES LIFT NE
INTO THE CAROLINAS LATE. NEW ECMWF MUCH SLOWER WITH THE SOUTHERN
SYSTEM LAGGING FARTHER SOUTH WHICH WOULD RESULT IN ONLY SPOTTY
PRECIP. FOR NOW KEPT LIKELY POPS FOR LATER SUNDAY NIGHT BUT WARMER
WITH PERHAPS ONLY THE HIGHER ELEVATIONS OVER THE FAR NW STAYING COLD
ENOUGH ALOFT FOR SNOW. OTRW LOWS STEADYING OUT IN THE 30S WEST TO
AROUND 40 SE.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 300 PM EST THURSDAY...
GENERAL FLAVOR OF MODEL GUIDANCE REMAINS THE SAME FOR THE EXTENDED
PERIOD AS A COLD FRONT MOVES THROUGH THE REGION SUNDAY NIGHT WITH A
WAVE RIDING UP ALONG THE FRONT FROM THE SOUTHEAST. LOW LEVEL WARM
AIR SURGING IN AHEAD OF THIS SYSTEM SHOULD HAVE PTYPE MOSTLY LIQUID
UNTIL COLD AIR PUSHES IN FROM THE NORTHWEST LATER ON MONDAY...AND WE
TRANSITION OVER TO SNOW AS BULK OF SYNOPTIC PCPN PULLS OUT. UPSLOPE
SNOW SHOWERS WILL THEN AFFECT AREAS WEST OF THE BLUE RIDGE MONDAY
NIGHT INTO TUESDAY WITH SOME ACCUMULATIONS POSSIBLE FOR THE WESTERN
SLOPES. MAY SEE AN UPTICK IN SNOW SHOWERS TOWARD DAYBREAK TUESDAY AS
A VIGOROUS SHORT WAVE MOVES SWINGS THROUGH THE BASE OF THE UPPER
TROF AND PASSES OVER THE REGION. HIGH PRESSURE WILL THEN PUSH IN
FROM THE SOUTHEAST AS MOISTURE RETREATS AND WE ARE QUIET AND COLD
FOR LATE TUESDAY INTO WEDNESDAY. HIGH PRESSURE SLIDES OFF TO OUR
EAST THURSDAY...ALLOWING SOUTHERLY RETURN FLOW TO MODERATE
TEMPERATURES A BIT BEFORE WE SEE AFFECTS OF NEXT SYSTEM APPROACHING
FROM THE MISSISSIPPI VALLEY THURSDAY NIGHT.
IT LOOKS LIKE MONDAY NIGHT THROUGH TUESDAY NIGHT WILL SEE THE BEST
CHANCES FOR WINDY CONDITIONS WITH GOOD DOWNWARD MOMENTUM TRANSFER
ABLE TO BRING STRONG LOW LEVEL WINDS TO THE SURFACE.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
AS OF 1155 PM EST THURSDAY...
SHORT WAVE MOVING INTO EASTERN VIRGINIA...WITH THE ASSOCIATED
PRECIPITATION ALSO MOVING EAST..AWAY FROM THE MOUNTAINS AND
PIEDMONT. LOW PRESSURE WAS DEEPENING OFF THE MID ATLANTIC COAST
WHICH WILL RESULT IN NORTHWEST WINDS AND UPSLOPE CLOUDS AND SNOW
SHOWERS IN THE MOUNTAINS. CLOUDS EAST OF THE BLUE RIDGE WILL
GRADUALLY CLEAR OVERNIGHT AND SHOULD BE OUT OF KLYH AND KDAN BY
12Z/7AM. WIND GUSTS COULD REACH 20 KNOTS OVERNIGHT. MVFR TO IFR
CLOUDS WILL PERSIST ON WESTERN SLOPES THROUGH MUCH OF FRIDAY.
MEDIUM CONFIDENCE FOR TIMING OF IMPROVEMENT TO VFR AT KLWB AND
KBLF.
HIGH PRESSURE BUILDS IN FRIDAY AND FRIDAY NIGHT. WINDS WILL
DIMINISH TO LESS THAN 10 KNOTS AFTER SUNSET ON FRIDAY. THE HIGH
WILL BRING IN DRIER AND COLDER AIR OF THE END OF THE WEEK.
EXTENDED DISCUSSION...
AN UPPER LEVEL TROUGH WILL DEVELOP OVER THE EASTERN U.S. AND MAKE
ITS WAY NORTHEAST THROUGH SATURDAY. ARCTIC HIGH PRESSURE WILL KEEP
MOST AREAS VFR INTO SATURDAY. THE EXCEPTION MAY BE SOME LATE
NIGHT RIVER OR VALLEY FOG.
SUNDAY INTO MONDAY...A COLD FRONT IS EXPECTED TO MOVE THROUGH THE
REGION. THIS WILL BRING SUB-VFR CONDITIONS AND A WINTRY MIX OF
PRECIPITATION. MODELS ARE COMING IN WARMER...SO THE TREND IS FOR
MORE RAIN AND LESS WINTER PRECIPITATION THREAT. MOST WINTER
PRECIPITATION SHOULD BE CONFINED TO THE MOUNTAINS...IMPACTING
KLWB/KBLF TO SOME EXTENT...BUT BY NO MEANS A SIGNIFICANT WINTER
EVENT. MORE WIDESPREAD -SHSN EXPECTED BEHIND THE FRONT MON NIGHT
INTO TUE WITH SOME ACCUMULATIONS POSSIBLE AT THAT TIME...AGAIN
MAINLY IMPACTING BLF/LWB. GUSTY NORTHWEST WINDS ARE EXPECTED
BEHIND THE SYSTEM ON TUESDAY.
&&
.CLIMATE...
RECORD COOLEST HIGHS
FRI NOV 14TH
BLACKSBURG VA...35 IN 1986
BLUEFIELD WV....29 IN 1975
DANVILLE VA.....39 IN 1997
ROANOKE VA......37 IN 1976
LEWISBURG WV....30 IN 1975
LYNCHBURG VA....37 IN 1996
SAT NOV 15TH
BLACKSBURG VA...32 IN 1976
BLUEFIELD WV....23 IN 1969
DANVILLE VA.....41 IN 1986
ROANOKE VA......34 IN 1969
LEWISBURG WV....29 IN 1995
LYNCHBURG VA....36 IN 1969
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS/DS
NEAR TERM...AMS/DS
SHORT TERM...JH
LONG TERM...MBS
AVIATION...AMS/DS
CLIMATE...DS
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
402 PM MST FRI NOV 14 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 357 PM MST FRI NOV 14 2014
COLD FRONT POISED JUST TO THE NORTH OF THE FORECAST AREA THIS
AFTERNOON. UPPER LEVEL WESTERLY FLOW PARALLELING THE FRONT AND
KEEPING IT FROM MAKING MUCH PROGRESS TO THE SOUTH. SNOW SHOULD BEGIN
SPREADING EAST ACROSS CONVERSE/NIOBRARA COUNTIES BETWEEN 00Z-03Z/SAT
AND INTO DAWES AND NORTHERN SIOUX COUNTIES IN THE NEBRASKA PANHANDLE
BETWEEN 03Z-05Z/SAT. BOTH THE NAM12 AND HRRR KEEP THE SNOW CONFINED
TO THESE AREAS THROUGH 06Z/SAT. ABOUT THAT TIME...MORE ROBUST BAND
OF SNOW WILL BEGIN TO DEVELOP OVER CARBON COUNTY...ESPECIALLY ALONG
THE INTERSTATE 80 CORRIDOR AND THE MEDICINE BOW AND SIERRA MADRE
RANGES. STRONGER FRONTAL SURGE COMES AFTER ABOUT 08Z/SAT AND PUSHES
TO THE SOUTHERN BORDER OF THE FORECAST AREA BY 13Z/SAT.
BEST SNOWFALL ALONG AND EAST OF I-25 SHOULD COME WITH AND SHORTLY
BEHIND THE FRONTAL PASSAGE. PLATTE...GOSHEN...AND LARAMIE COUNTIES
ALONG WITH THE REMAINDER OF THE PANHANDLE SHOULD SEE 1 TO 3 INCH
AMOUNTS. FRONTOGENETIC FORCING DOES FAVOR SOME ENHANCED LIFT IN
LARAMIE COUNTY WHERE IMPACTS COULD STILL NECESSITATE AN UPGRADE TO A
WINTER WEATHER ADVISORY. THE EVENING SHIFT WILL NEED TO MONITOR
TRENDS FROM 00Z OUTPUT CLOSELY. IN ADDITION TO THE
SNOW...NORTHERLY WIND OF 15 TO 30 MPH WILL PREVAIL FOLLOWING COLD
FRONTAL PASSAGE. ELSEWHERE...ADVISORIES LOOK TO BE IN GOOD SHAPE
WITH FORECAST STILL ON THE CORRECT TRACK. AIRMASS SLOWLY DRIES
AFTER 18Z/SAT BUT ANY SUN WILL JUST ALLOW FOR COLD AIR
STRATOCUMULUS TO DEVELOP. OVERALL... SHOULD BE A MOSTLY CLOUDY
DAY. RAPID CLEARING WILL OCCUR AFTER SUNSET SATURDAY. GIVEN A
FRESH SNOW COVER AND A LACK OF CLOUDS...WOULD NOT BE SURPRISED TO
SEE TEMPERATURES DROP BELOW GUIDANCE. IN OUR FAVOR WOULD BE A
CONTINUING WEST WIND IN SOME AREAS THAT WILL HELP KEEP THE
BOUNDARY LAYER BETTER MIXED. THOSE AREAS LACKING WIND WILL
UNDOUBTEDLY AGAIN SEE SUB-ZERO TEMPERATURES.
NORTHERLY FLOW WILL BE REINFORCED SUNDAY AS 100KT+ JET DIVES SOUTH
OUT OF SASKATCHEWAN. HIGH-AMPLITUDE RIDGE BUILDING ALONG THE WEST
COAST WILL KEEP THE FORECAST AREA IN CYCLONIC FLOW THROUGH AT LEAST
SUNDAY NIGHT. TAIL END OF SHORTWAVE ENERGY MOVING THROUGH THE
NORTHERN PLAINS WILL BRUSH THE EASTERN TWO-THIRDS OF THE FORECAST
AREA SUNDAY. THIS WILL BRING ADDITIONAL CLOUD COVER AND ANOTHER WEAK
SHOT OF COLDER AIR. GUSTY NORTHWEST WIND 20 TO 30 MPH WILL MAKE FOR
A RAW DAY EVEN WITH TEMPERATURES REBOUNDING FROM THE COLDER AIR OF
SATURDAY AND SATURDAY NIGHT. LOW TEMPERATURES SUNDAY NIGHT WILL BE
LARGELY DEPENDENT ON HOW MUCH CLOUD COVER REMAINS...ESPECIALLY OVER
THE EASTERN PLAINS OF WYOMING AND THE PANHANDLE.
.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 357 PM MST FRI NOV 14 2014
LOOKS LIKE DRY NORTHWEST FLOW ALOFT OVER THE FORECAST AREA FOR MUCH
OF THE EXTENDED. GRADIENT IS SUCH THAT BREEZY TO WINDY CONDITIONS
WILL PERSIST EARLY IN THE EXTENDED PERIOD. SHORTWAVE RIDGE ALOFT
DEPICTED FOR WEDNESDAY AND THURSDAY WITH WARMER TEMPERATURES. CANNOT
RULE OUT A FEW SNOW SHOWERS OVER THE SNOWY AND SIERRA MADRE
RANGES...POSSIBLY MORE SO FRIDAY WITH PASSAGE OF DEEPENING MID LEVEL
TROUGH. WILL HAVE TO SEE HOW THIS TROUGH OR SHORTWAVE EVOLVES FOR
LATE THURSDAY NIGHT INTO FRIDAY...BUT NO SIGNIFICANT STORM SYSTEMS
DURING THIS PERIOD. TEMPERATURES SHOULD BE AROUND NORMAL.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 357 PM MST FRI NOV 14 2014
VFR CONDITIONS EXPECTED AT ALL TERMINALS UNTIL ABOUT 02Z/SAT. FIRST
SURGE OF COLDER AIR WILL BEGIN TO GENERATE LIGHT SNOW GENERALLY
ALONG AND NORTH OF A KDGW-KCDR LINE BETWEEN 02Z-05Z. CONDITIONS WILL
BECOME MVFR AND EVENTUALLY IFR BY 06Z/SAT AT KCDR. KAIA AND KBFF
WILL BEGIN TO GET IN ON THE ACTION WITH MVFR EXPECTED AROUND 06Z/SAT
AS THE AREA OF LIGHT SNOW SAGS SLOWLY SOUTH. ABOUT THE SAME TIME...
APPEARS THAT A BETTER BAND OF SNOW WILL EXTEND EAST INTO CARBON
COUNTY AND IMPACT KRWL BY 08Z/SAT. A SECOND WAVE OF SNOW WILL THEN
DEVELOP AS A STRONGER FRONTAL SURGE TRAVERSES THE FORECAST AREA FROM
NORTH TO SOUTH FROM 08Z TO 13/SAT. GUSTY NORTHERLY WIND OF 15-30KTS
WILL ACCOMPANY AND FOLLOW FRONTAL PASSAGE. IFR AND LIFR CONDITIONS
WILL BE WIDESPREAD WITH THE HEAVIEST SNOWFALL LIKELY TO OCCUR
BETWEEN ABOUT 10Z-15Z/SAT. DRIER CONDITIONS SHOULD BEGIN TO PUSH
ACROSS THE FORECAST AREA FROM NORTH-TO-SOUTH BETWEEN 15Z-20Z/SAT.
THERE SHOULD BE ENOUGH COLD AIR ALOFT THAT ANY PARTIAL CLEARING WILL
ALLOW FOR STRATOCUMULUS TO FORM...ALTHOUGH CONDITIONS SHOULD BE VFR
AFTER ABOUT 19Z/SAT. MOUNTAIN OBSCURATIONS WILL BE WIDESPREAD FROM
SHORTLY AFTER 00Z/SAT UNTIL ABOUT 18Z/SAT. MOUNTAIN TOP OBSCURATIONS
WILL CONTINUE AFTER THAT TIME UNTIL SUNSET LATE SATURDAY
AFTERNOON.
&&
.FIRE WEATHER...
ISSUED AT 357 PM MST FRI NOV 14 2014
NO FIRE WEATHER CONCERNS THROUGH THIS WEEKEND. ANOTHER ARCTIC SYSTEM
WILL BRING SNOW ACROSS MOST AREAS THROUGH SATURDAY. SEVERAL INCHES
OF SNOW WILL ACCUMULATE...ESPECIALLY IN THE HIGHER ELEVATIONS OF
SOUTHERN WYOMING. THIS SNOW WILL BE FOLLOWED BY BRISK SURFACE WIND
AND COLD TEMPERATURES SUNDAY INTO SUNDAY NIGHT.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER WEATHER ADVISORY UNTIL 11 AM MST SATURDAY FOR WYZ101>103.
WINTER WEATHER ADVISORY FROM 11 PM THIS EVENING TO 1 PM MST
SATURDAY FOR WYZ104>106-109>111-113-115>117.
WINTER WEATHER ADVISORY UNTIL 11 AM MST SATURDAY FOR WYZ112-114.
NE...WINTER WEATHER ADVISORY UNTIL 11 AM MST SATURDAY FOR NEZ002-095.
&&
$$
SHORT TERM...RIW/ZF
LONG TERM...RIW/CAH
AVIATION...RIW/CAH
FIRE WEATHER...RIW/ZF
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1014 PM MST SAT NOV 15 2014
.UPDATE...
ISSUED AT 759 PM MST SAT NOV 15 2014
MAIN BAND OF HEAVIER SNOW NOW DROPPING INTO EL PASO COUNTY...AND
EXPECT SNOWFALL RATES TO INCREASE WITH A QUICK 2-4 INCHES LIKELY
BY MIDNIGHT. FARTHER SOUTH...HAD TO INCREASE FORECAST SNOW
AMOUNTS SLIGHTLY OVER PUEBLO COUNTY WHERE 1-2 INCHES HAS ALREADY
FALLEN AND 00Z NAM SUGGESTS ANOTHER 2-4 POSSIBLE. MADE ONLY MINOR
ADJUSTMENT ELSEWHERE.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 330 PM MST SAT NOV 15 2014
...WIDESPREAD SNOW TO IMPACT THE REGION TONIGHT...
COLD FRONT HAS ALREADY DROPPED THROUGH SOUTHEAST COLORADO THOUGH
CORE OF COLDER AIR IS STILL SITTING ACROSS NORTHEAST COLORADO AND
NORTHERN EL PASO COUNTY WHERE TEMPERATURES ARE IN THE TEENS (VS. THE
UPPER 20S AND 30S ACROSS THE REMAINDER OF THE SOUTHEAST PLAINS).
MAIN UPPER TROF IS CURRENTLY ACROSS WY/ID AND WILL CONTINUE DROPPING
SOUTHWARD INTO THE 4 CORNERS REGION TONIGHT. UPPER JET ACROSS CO
HAS LED TO SOME BANDED SNOW ACROSS NORTHEAST COLORADO...WITH SOME
PERIODIC LIGHT SNOW CONTINUING ACROSS THE NORTHERN PORTIONS OF
MONUMENT HILL WHERE MOST OF THE FORCING IS LIKELY DUE TO SHALLOW
OROGRAPHICS. SNOW ALSO CONTINUES ALONG THE CONTINENTAL
DIVIDE...THOUGH INTENSITIES HAVE LET UP QUITE A BIT FROM THIS
MORNING. THAT WILL BE CHANGING IN THE NEXT 6 HOURS THOUGH AS
DYNAMICS FROM THE UPPER TROF SHIFTS SOUTHWARD WITH TIME. BEST QG
FORCING APPEARS TO DROP THROUGH THE WESTERN AND SOUTHERN PORTIONS OF
THE FORECAST AREA. CHALLENGES STILL REVOLVE AROUND SNOW AMOUNTS.
MODELS APPEAR TO BE STRUGGLING THE MOST ACROSS THE PIKES PEAK
REGION...WITH GFS PREDICTING A HEALTHY 3-7 INCHES ACROSS THIS
REGION...WHILE NAM12 HAS MORE IN THE 1 TO 3 INCH RANGE. RAP IS
GOING ALONG WITH GFS...WHILE ECMWF AND OTHER HIGH RES MODELS
(ARW..NMM) AGREE MORE WITH THE NAM. SO HAVE TO HUNT FOR CLUES TO
SUGGEST WHERE TO PUT THE NORTHERN EDGE OF THE HEADLINE AREAS. GIVEN
THE TRACK OF THE UPPER FORCING IS FARTHER TO THE SOUTH...AND THE
BEST UPGLIDE OVER THE H7 FRONT SEEMS TO BE MORE ACROSS SOUTHERN
AREAS...HAVE LEFT PIKES PEAK AND EL PASO COUNTY OUT OF THE ADVISORY
AREA FOR NOW. SNOWFALL GRIDS WILL CARRY AROUND 2-5 INCHES WITH
SOUTHERN EL PASO COUNTY MORE IN THE 2 TO 3 INCH RANGE.
WHERE MODELS AGREE BETTER IS ACROSS THE SOUTHEAST MOUNTAINS AND
SOUTHERN I-25 CORRIDOR. HAVE EXPANDED THE ADVISORIES NORTHWARD AND
EASTWARD A TAD. PUEBLO COUNTY IS ALWAYS A CHALLENGE AS HEAVIER
AMOUNTS MAY END UP ACROSS SOUTHERN AND WESTERN PORTIONS OF THE
COUNTY WHILE NORTHEAST PORTIONS SEE MORE IN THE 1-3 INCH RANGE. ALL
THE MODELS SEEM TO HIT THE SOUTHERN SANGRES WITH THE HEAVIEST
AMOUNTS OF QPF...AND THIS LOOKS REASONABLE GIVEN THE TRACK OF THE
SYSTEM. THUS HAVE UPGRADED THE WINTER WEATHER ADVISORY TO A WARNING
FOR THE SOUTHERN SANGRES. HAVE ALSO ADDED EASTERN LAS ANIMAS COUNTY
TO THE ADVISORY WHERE THE NORTHERN SLOPES OF THE RATON WILL HAVE THE
BENEFIT OF SOME NORTHEAST OROGRAPHICS.
WILL HOLD ON TO THE WINTER STORM WARNINGS ALONG THE CONTINENTAL
DIVIDE. THESE AREAS SHOULD PICK UP ANOTHER 5 TO 10 INCHES OVERNIGHT
WITH THE HEAVIEST ACROSS SOUTHERN PORTIONS OF THE EASTERN SAN JUAN
MOUNTAINS.
A COUPLE OTHER CHALLENGING SPOTS INCLUDE THE SAN LUIS VALLEY WHERE
HIGH RES MODELS ARE NOT SHOWING MUCH SNOW. HAVE GONE WITH AROUND AN
INCH TO 1.5 ACROSS THE VALLEY FLOOR GIVEN THIS AREA WILL BE IN
BETTER PROXIMITY TO THE UPPER DYNAMICS. BEST CHANCE WILL COME IN
AFTER 10 PM FOR THIS AREA. BACA COUNTY IS THE FINAL CHALLENGE.
MODEL RUNS WERE SUGGESTING AROUND 2 TO 4 INCHES OUT THAT WAY...JUST
SHY OF ADVISORY CRITERIA...BUT LATEST NAM12 HAS COME IN HEAVIER...SO
THIS AREA MAY HAVE TO BE MONITORED CLOSELY IF THE HEAVIER SNOW BAND
SETS UP ACROSS THAT AREA.
HIGHLIGHTS WILL PARE OFF FROM NORTH TO SOUTH TOWARDS MORNING. MOST
OF THE SNOW WILL BE DONE BY 10Z UP NORTH...AND BY 13-16Z DOWN SOUTH.
MOSTLY SUNNY SKIES WILL RETURN BY MID DAY SUNDAY. TEMPERATURES
TONIGHT WILL DROP BACK DOWN INTO THE SINGLE DIGITS FOR MOST OF THE
SOUTHEAST PLAINS WHERE THE CORE OF THE COLDER AIR WILL SPREAD IN.
SOME SPOTS COULD DROP INTO THE NEGATIVE DIGITS UP NORTH IF CLEARING
CAN OCCUR EARLY ENOUGH. SAN LUIS VALLEY WILL HAVE THE BENEFIT OF
CLOUDS AND PRECIPITATION OVERNIGHT SO LOWS THERE MAY ONLY DROP INTO
THE TEENS. KEPT HIGH TEMPERATURES ON SUNDAY CLOSER TO THE COLDER
SIDE OF GUIDANCE. -KT
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 330 PM MST SAT NOV 15 2014
...A SLOW WARMING TREND...
A SLOW WARMING TREND TO AROUND MID NOVEMBER AVERAGES REMAINS IN THE
OFFING INTO THE MIDDLE OF THE UPCOMING WORK WEEK...AS COLD NORTH TO
NORTHWEST FLOW ALOFT ACROSS THE REGION SUNDAY NIGHT GIVES WAY TO
WARMER MORE WESTERLY FLOW BY WEDNESDAY. TEMPERATURES TO BE THE MAIN
CONCERN AND HEADACHE IN THE SHORT TERM...WITH HIGHS AND LOWS TO BE
INFLUENCED BY SNOW COVER. AT ANY RATE...HAVE GONE AT OR BELOW THE
COLDER SIDE OF GUIDANCE FOR SUNDAY NIGHT AND MONDAY...ESPECIALLY
ACROSS THE SOUTHEASTERN MTS AND PLAINS WITH LOWS IN THE SINGLE
DIGITS ABOVE AND BELOW ZERO AND HIGHS MAINLY IN THE 20S. INDUCED LEE
TROUGHING AHEAD OF A SHORT WAVE TRANSLATING ACROSS THE NORTHERN
ROCKIES SHOULD KEEP LOWS SLIGHTLY WARMER ACROSS THE EASTERN SLOPES
MONDAY NIGHT AND COULD BOOST HIGHS INTO THE 30S TO LOWER 40S
ACROSS THE LOWER ELEVATIONS ON TUESDAY.
BUILDING UPPER RIDGE ACROSS THE GREAT BASIN TUESDAY NIGHT FLATTENS
ACROSS THE STATE THROUGH WEDNESDAY NIGHT AS MINOR WAVES TRANSLATE
EAST ACROSS THE GREAT BASIN AND ROCKIES...WITH THE DOWNSLOPE FLOW
OWNING TO THE EXPECTED WARMING TEMPERATURES AND BRINGING CHANCES
OF LIGHT SNOWFALL TO THE HIGHER TERRAIN...MAINLY ALONG AND WEST OF
THE CONTDVD THURSDAY AND FRIDAY. LATEST MODELS ARE SHOWING A
STRONGER SYSTEM MOVING ACROSS THE GREAT BASIN FRIDAY AND ACROSS
THE ROCKIES ON SATURDAY...THOUGH BOTH THE GFS AND EC HAVE SHOWN
RUN TO RUN INCONSISTENCIES ON ITS TIMING AND STRENGTH. FOR
NOW...HAVE KEPT ANY PRECIPITATION CHANCES CONFINED TO THE HIGHER
TERRAIN FRIDAY NIGHT AND SATURDAY WITH TEMPERATURES AROUND
SEASONAL AVERAGES.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1002 PM MST SAT NOV 15 2014
AT KALS...STILL A WINDOW FOR OCCASIONAL LIGHT SNOW AND MVFR/BRIEF
IFR CONDITIONS 06Z-12Z AS WEATHER SYSTEM MOVES THROUGH SOUTHERN
COLORADO. SNOW SHOULD END 12Z-14Z SUN MORNING...WITH VFR
CONDITIONS THROUGH THE REMAINDER OF THE DAY.
AT KCOS...BACK EDGE OF STEADIER/HEAVIER SNOW ALREADY SOUTH OF
DENVER METRO AS OF 05Z...THUS EXPECT IFR CONDITIONS AND HEAVIER
SNOW TO END 06Z-08Z...ALTHOUGH LIGHTER SNOW AND MVFR CIGS WILL
PERSIST UNTIL AROUND 12Z. EXPECT VFR CONDITIONS FROM 12Z-13Z
THROUGH THE REMAINDER OF SUNDAY AS WEATHER SYSTEM MOVES SOUTH OF
THE AREA.
AT KPUB...STILL A FEW MORE HOURS OF SNOW AND IFR/LIFR
CONDITIONS...WITH GRADUAL IMPROVEMENT TO MVFR AFTER 09Z AS SNOW
BAND SHIFTS SOUTH. EXPECT VFR CONDITIONS FROM 13Z THROUGH THE
REMAINDER OF SUNDAY AS WEATHER SYSTEM DROPS SOUTH INTO NM.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 9 AM MST SUNDAY FOR COZ072-073-079-
080-087-088-094.
WINTER WEATHER ADVISORY UNTIL 5 AM MST SUNDAY FOR COZ077-078-083-
086.
WINTER STORM WARNING UNTIL 5 AM MST SUNDAY FOR COZ058-060-066.
WINTER STORM WARNING UNTIL 9 AM MST SUNDAY FOR COZ068-074-075.
&&
$$
UPDATE...PETERSEN
SHORT TERM...KT
LONG TERM...MW
AVIATION...PETERSEN
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
410 AM EST SUN NOV 16 2014
.SYNOPSIS...
ISSUED AT 400 AM EST SUN NOV 16 2014
A WEAK SYSTEM THIS MORNING WILL BRING A CHANCE FOR LIGHT SNOW
ACROSS THE REGION WITH ONLY LITTLE OR NO ACCUMULATIONS. A
STRONGER SYSTEM WILL APPROACH LATER THIS AFTERNOON AND TONIGHT
WITH SNOW DEVELOPING FROM CENTRAL ILLINOIS THROUGH CENTRAL AND
NORTH CENTRAL INDIANA AND INTO OHIO. SNOW ACCUMULATIONS TONIGHT
WILL RANGE FROM AN INCH OR LESS NEAR THE MICHIGAN AND INDIANA
STATE LINE TO AS MUCH AS 5 INCHES OVER CENTRAL INDIANA AND OHIO.
WINTER WEATHER ADVISORIES ARE IN EFFECT FOR PARTS OF THE REGION.
HIGHS TODAY WILL BE IN THE LOWER AND MIDDLE 30S. LOWS TONIGHT WILL
BE IN THE 20S. A STRONG ARCTIC COLD FRONT WILL BRING MUCH COLDER
TEMPERATURES ON MONDAY.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 352 AM EST SUN NOV 16 2014
NUMEROUS ISSUES TO DEAL WITH IN THE SHORT TERM PERIOD. DESPITE
THE CALENDAR INDICATING MID NOVEMBER MOTHER NATURE TREATING US TO
DECEMBER LIKE WEATHER. WATER VAPOR TELLS THE STORY EARLY THIS
MORNING WITH BROAD SOUTHWEST FLOW DEVELOPING AND MOISTURE
SPREADING NORTHEAST FROM THE CENTRAL CONUS. THIS IN RESPONSE TO
DIGGING LONG WAVE TROUGH INTO THE CENTRAL CONUS WITH ARCTIC AIR
QUICKLY INVADING BEHIND A POLAR COLD FRONT. NUMEROUS EMBEDDED
SHORT WAVES SEEN ON VAPOR. SHEARED VORTS TO MOVE ACROSS THE CWA
TODAY AND WITH THE MODEST MOISTURE MODELS HINTING AT LIGHT SNOW
DEVELOPING...ESPECIALLY WEST AND NORTH. THIS SHOULD REMAIN LIGHT
AND EVEN SOME DOUBT ABOUT HOW MUCH LOWER LEVELS WILL SATURATE TO
ALLOW FOR ANY MEASURABLE PCPN. DID CONTINUE WITH LOW CHANCE POPS
INTO THE AFTERNOON WITH SOME VERY LIGHT QPF/SNOW IN GRIDS.
THE MOIST SOUTHWEST FLOW HAS ALSO ALLOWED A RARE SOUTHWEST TO
NORTHEAST ORIENTED LAKE PLUME TO DEVELOP OVER FAR NORTHERN BERRIEN
COUNTY. BEST FORCING REMAINS OVER THE EXTREME NORTHERN TIP OR JUST
OUTSIDE THE COUNTY THROUGH THE ENTIRE SHORT TERM PERIOD. HAVE
ALREADY SEEN A FEW BANDS DEVELOP AND MOVE THROUGH WITH VISIBILITY
DROPPING BELOW A MILE. HIRES GUIDANCE ALL INDICATE THIS PLUME
MEANDERING NEAR THE NORTHERN TIP SO ALLOWED LIKELY POPS TO RIDE
THROUGH THE PERIOD WITH ACCUMS OF 1 TO 3 INCHES DEPENDING ON HOW
LONG ANY BAND PERSISTS.
NEXT CONCERN LIES WITH SYNOPTIC MOISTURE AND SHEARED SHORT WAVES
ARRIVING LATER THIS AFTERNOON AND MOVING THROUGH CENTRAL AND
SOUTHERN AREAS TONIGHT. VERY GOOD MODEL AGREEMENT WITH 2-3 G/KG OF
MOISTURE WITH MODEST ISENTROPIC LIFT. THE POTENT FACTOR FOR
DEVELOPING BAND OF MODERATE SNOW FOR A FEW HOURS APPEARS TO BE
STRONG DEVELOPING MID LEVEL JET STREAK ALONG WITH LOW LEVEL
FRONTOGENETICAL FORCING. NAM12 SHOWS A 130KT JET STREAK AT 00Z WITH
RIGHT ENTRANCE REGION PASSING OVER SOUTHERN CWA WITH GOOD
DIVERGENCE ALOFT. THIS SHOULD PROMOTE GOOD LIFT WITH THE REGION OF
BEST FGEN FORCING AND MOISTURE ADVECTION. MOST MODEL GUIDANCE
SHOWING AROUND A QUARTER INCH OF QPF WITH AVERAGE RATIOS OF AROUND
15 TO 1. USING WPC QPF AND NAM12 RATIOS YIELDS A BAND OF GENERAL 2
TO 4 INCHES FROM GRANT COUNTY NORTHEAST TO PUTNAM COUNTY. MESOSCALE
PROCESSES MAY ALLOW A FEW HIGHER AMOUNTS BUT QUESTION IS IF THAT
WILL BE WITHIN OUR CWA OR JUST SOUTH WHERE A BIT DEEPER MOISTURE
RESIDES. COORDINATION WITH SURROUNDING OFFICES AND GOOD MODEL
AGREEMENT ON AMOUNTS HAS LED TO ISSUANCE OF A WINTER WEATHER
ADVISORY FROM ABOUT MARION TO VAN WERT AND OTTAWA FROM EARLY THIS
EVENING THROUGH 14Z MONDAY MORNING. GIVEN THIS WILL BE THE FIRST
SIGNIFICANT ACCUMULATING SNOW OF THE SEASON FOR THIS REGION AND
BORDERLINE ADVISORY CRITERIA FELT IT PRUDENT TO ISSUE THE ADVISORY
WHICH MATCHES WELL WITH NEIGHBORS TO THE SOUTH AND EAST.
&&
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 352 AM EST SUN NOV 16 2014
...ARCTIC FRONT POISED TO MOVE THROUGH MONDAY...
SHORTWAVE WILL BE EXITING TO THE EAST AT THE START OF THE PERIOD AS
ADVERTISED ARCTIC BOUNDARY AND ASSOCIATED DEEP UPPER LOW TRACK INTO
THE REGION...ALLOWING FOR A QUICK END TO ANY REMAINING AREAS OF SNOW
IN FAR SE AREAS (WILL HOLD ONTO CHC POPS IN THE AM). COLD AIR WILL
QUICKLY FILTER IN MONDAY WITH THE FRONT LIKELY CLEARING THE FORECAST
AREA BY 21Z MON IF NOT BEFORE. HIGH TEMPERATURES IN THE WEST WILL
OCCUR EARLY ON MONDAY WITH FALLING TEMPERATURES INTO THE AFTERNOON.
EASTERN AREAS MAY RISE A FEW DEGREES PRIOR TO FRONTAL PASSAGE BUT
WILL OTHERWISE SUFFER THE SAME FATE IN THE AFTERNOON. SOME FLURRIES
OR LIGHT SNOW SHOWERS MAY ACCOMPANY THE FRONT...WITH WINDS
INCREASING IN ITS WAKE.
FOCUS THEN QUICKLY SHIFTS TO LAKE EFFECT ISSUES AS THE COLD AIR
STREAMS IN AND 850 MB TEMPS DROP TO -15 TO -17 C LATE MONDAY NIGHT.
AS IS EXPECTED THE BATTLE IS ON WITH MODELS VARYING ON EXACT
TRAJECTORY OF THE FETCH...LOCATION OF ONE OR MORE BANDS OF LAKE
EFFECT SNOW AND BOUNDARY LAYER MOISTURE. WHAT THEY DO ALL AGREE ON
IS EXTREME INSTABILITY AND LIFT WILL BE IN PLACE AS EARLY AS MONDAY
MORNING WITH AND FAVORABLY DEEP DENDRITIC GROWTH ZONE. THE CONSENSUS
AT LEAST POINTS TOWARDS BERRIEN AND CASS COUNTIES STILL IN THE MOST
FAVORABLE AREA FOR POTENTIALLY SIGNIFICANT SNOW AMOUNTS IN SOME
AREAS. NORTHERN BERRIEN COUNTY WILL BE FURTHER COMPLICATED WITH LAKE
EFFECT DISCUSSED IN THE SHORT TERM. GIVEN THE SIGNALS AND INCREASING
CONFIDENCE WILL HOIST A WINTER STORM WATCH FOR LAKE EFFECT SNOW
SHOWERS AND BLOWING SNOW FOR THE MENTIONED COUNTIES STARTING 12Z MON
INTO 00Z WEDS. THE WORST CONDITIONS WILL COME MAINLY FROM 00Z TUES
TO 00Z WEDS AS PIECE OF ENERGY ROTATES AROUND THE UPPER LOW AND
GIVES THE SHOW SHOWERS A NICE BOOST (AND BETTER BOUNDARY LAYER
MOISTURE POTENTIAL). WAY TO EARLY TO PIN DOWN ANY SPECIFIC AMOUNTS
GIVEN WHAT MAY BE SOMEWHAT TRANSITORY BANDS BUT SAFE TO SAY
WHEREVER THE BANDS SIT THEY WILL LIKELY BE ACCOMPANIED BY RATES OF
1 TO 2 INCHES PER HOUR AND LOCALLY HIGHER RATES POSSIBLE. NOT TO
FORGET THE REST OF THE AREA...SNOW SHOWERS WILL LIKELY EXTEND INTO
AT LEAST THE US-6 AND POINTS NORTH CORRIDOR INTO TUESDAY WITH MAINLY
FLURRIES OR A PASSING LIGHTER SNOW SHOWER SOUTH OF 6.
A COLD NIGHT WILL BE IN STORE MONDAY NIGHT WITH ANOTHER TUESDAY
NIGHT AS PLUMMET INTO THE TEENS AND EVEN SINGLE DIGITS AWAY FROM THE
LAKE. TUESDAY HIGHS CONTINUE TO TREND COOLER WITH NOT MUCH DIURNAL
SWING AS TEMPERATURES STRUGGLE TO REACH THE UPPER TEENS TO AROUND 20
(A SOLID 30 DEGREES OR MORE BELOW NORMAL). LOW MAX TEMPERATURE
RECORDS AT SBN AND FWA WILL LIKELY BE BROKEN ON TUESDAY (26 AND 24
RESPECTIVELY). LET`S NOT FORGET THE WIND CHILLS MONDAY NIGHT INTO
TUESDAY MORNING WILL LIKELY BE BELOW ZERO AND POSSIBLE INFRINGING ON
MINUS 10 IN SOME AREAS. WILL CONTINUE TO HIGHLIGHT BITTER COLD TEMPS
(BY NOVEMBER STANDARDS) IN THE HWO.
COLDEST AIR WILL QUICKLY DEPART BY WEDNESDAY ALLOWING FOR MORE
COMFORTABLE...BUT STILL BELOW NORMAL TEMPERATURES. FEW OVERALL
CHANGES AS ACTIVE PATTERN WILL PERSIST AS SEVERAL EMBEDDED WAVES
DROP THROUGH THE NW FLOW INTO THE REGION EVERY FEW DAYS. EXACT
TIMING AND TRACK DETAILS REMAIN MUDDLED SO RAN WITH BLEND OF MODELS
FOR THE MOST PART.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1239 AM EST SUN NOV 16 2014
LOWER LEVELS FINALLY SATURATED NEAR KSBN WITH LIGHT SNOW FALLING. SHOULD
BE DONE NEAR OR JUST AFTER 06Z AS RADAR TRENDS ARE DECREASING SO
WILL CARRY A BRIEF MVFR TEMPO GROUP. OTHERWISE STAYED WITH VFR INTO
THE DAY ON SUNDAY. LATEST HRRR GUIDANCE IS SUGGESTING SOME MVFR
AND IFR CIGS DEVELOPING OVERNIGHT BUT NO SIGNS YET AND WITH VFR CLOUD
COVER IN PLACE OPTED TO HOLD OFF AND MONITOR TRENDS. NEXT SYSTEM
MOVES IN SUNDAY AFTERNOON WITH SYSTEM SNOW SPREADING EAST LATE
AFTERNOON AND ESPECIALLY AFTER 00Z. KSBN WILL BE JUST TO THE
NORTHWEST SO ONLY SOME FLURRIES OR VERY LIGHT SNOW THERE WITH NO
RESTRICTION TO VIS. KFWA WILL BE CLOSER TO DEEPER LIFT AND
MOISTURE WITH VIS DROPPING TO IFR LEVELS AFTER 00Z.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...WINTER WEATHER ADVISORY FROM 5 PM THIS AFTERNOON TO 9 AM EST
MONDAY FOR INZ026-027-032>034.
MI...WINTER STORM WATCH FROM MONDAY MORNING THROUGH TUESDAY EVENING
FOR MIZ077-078.
OH...WINTER WEATHER ADVISORY FROM 5 PM THIS AFTERNOON TO 9 AM EST
MONDAY FOR OHZ016-024-025.
LM...NONE.
&&
$$
SYNOPSIS...T
SHORT TERM...LASHLEY
LONG TERM...FISHER
AVIATION...LASHLEY
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSNORTHERNINDIANA
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
1245 AM EST SUN NOV 16 2014
.SYNOPSIS...
ISSUED AT 553 PM EST SAT NOV 15 2014
A WEAK DISTURBANCE ALOFT WILL LIFT THROUGH THE WESTERN GREAT LAKES
TONIGHT. A FEW FLURRIES OR PATCHY LIGHT SNOW IS POSSIBLE ACROSS
NORTHWEST INDIANA AND SOUTHWEST MICHIGAN BUT MOST LOCATIONS WILL
REMAIN DRY. LOWS TONIGHT WILL BE IN THE 20S.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 325 PM EST SAT NOV 15 2014
CHANCES FOR LIGHT SNOW REMAIN THE PRIMARY FOCUS THIS PERIOD. WEAK
SYSTEM RELATIVE ISENTROPIC ASCENT AND PV ADVECTION ASSOCIATED WITH
AN IA/NRN MO LEAD SHORTWAVE WILL LIFT ENE THROUGH MAINLY
NORTHWESTERN ZONES LATER THIS EVENING INTO THE EARLY OVERNIGHT.
THE BULK OF THIS BROAD/WEAK UVM WILL MAINLY GO TO SATURATION WITH
MORE FOCUSED FORCING INTO THE WESTERN LAKES...AND LIMITED
MOISTURE RETURN IN THE 900-700 MB LAYER (~1.5 G/KG). AS A RESULT
CONTINUED TREND TOWARD LOWER POPS/MORE VIRGA WITH NOTHING MORE
THAN A LIGHT COATING OF SNOW AT BEST. ONLY EXCEPTION MAY BE ACROSS
NRN BERRIEN/NW CASS COUNTIES IN MICHIGAN WHERE SW FLOW LAKE
ENHANCEMENT AND DEEPER MOISTURE MAY SUPPORT A PERIOD OF MORE
SUBSTANTIAL SNOW AND MINOR ACCUMULATIONS.
SUNDAY WILL FEATURE MAINLY CLOUDY SKIES AND HIGHS IN THE 30S.
TRAILING SHEARED VORTICITY AND WEAK MID LEVEL FGEN ASSOCIATED WITH
ADDITIONAL SHORTWAVE ENERGY (AND CONSOLIDATING MID/UPPER LEVEL JET)
MODELED TO STREAK INTO THE GREAT LAKES REGION MAY BE ENOUGH TO TOUCH
OFF A FEW FLURRIES/SNOW SHOWERS (BEST CHANCES NORTHWEST). AS FOR
TEMPERATURES TONIGHT-SUNDAY...ONLY MINOR TWEAKS MADE TO SLIGHTLY
WARMER TEMPS (HIGHS STILL 11-16F BELOW NORMAL) IN ADVANCE OF THE
NEXT ARCTIC FRONT.
&&
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 325 PM EST SAT NOV 15 2014
...ARCTIC AIRMASS WILL MAINTAIN A GRIP THROUGH THE EARLY PART OF
NEXT WEEK...
DURING THE OVERNIGHT SUNDAY INTO MONDAY MORNING...THERE IS
REASONABLE CONFIDENCE FOR THE DEVELOPMENT OF AN AREA OF SNOW TO FORM
SOUTH AND EAST OF THE FORECAST AREA. ALL OF THE MODELS HAVE BEEN
HINTING AT A SYSTEM LIFTING OUT OF THE MISSISSIPPI RIVER VALLEY AND
INTO THE OHIO RIVER VALLEY DURING THIS PERIOD...BUT THE POSITION...
INTENSITY...PHASING AND TIMING HAVE BEEN HIGHLY VARIABLE. IT DOES
APPEAR THAT THE BEST CHANCE FOR MEASURABLE SNOW WILL BE OUTSIDE OF
OUR AREA. AS THE COLD AIR CHARGES INTO THE AREA FROM THE NORTH THE
LAKE EFFECT WILL ENHANCE AND THE SYSTEM LIFTING THROUGH THE OHIO
RIVER VALLEY WILL LIKELY INTENSIFY AS IT MOVES NORTH AND EAST. NET
RESULT IS THAT THERE WILL BE A DISTINCT AND DRAMATIC LINE BETWEEN
ACCUMULATION AND DUSTING OF SNOW. DO NOT HAVE ENOUGH CONFIDENCE TO
ISSUE A HEADLINE FOR SUNDAY NIGHT/MONDAY MORNING. THIS WILL BEAR
MONITORING FOR LATER UPDATES.
LONGWAVE PATTERN IS BEGINNING TO SHAPE UP FOR A CONTINUED AND
PROLONGED COLD EXTENDED FORECAST. INITIAL SHOT OF COLD AIR SWEEPS IN
ON MONDAY. WEST COAST RIDGE CONTINUES TO ERODE AS A CONTINUED STREAM
OF COLD AIR PUSHES SOUTH INTO THE CANADIAN PLAINS. ADDITIONALLY THE
WESTERLIES OFF OF THE ASIAN CONTINENT ARE QUICK ENERGETIC AS EVIDENT
IN THE NORTHERN HEMISPHERIC WATER VAPOR IMAGERY. THE LONG RANGE
MODELS ALL SUGGEST THAT THERE WILL BE A NUMBER OF FAST MOVING
SYSTEMS WHIPPING ACROSS THE PACIFIC AND THESE CONTINUE TO UNDERCUT
THE WEST COAST RIDGE.
EVEN WITH THE GFS SUGGESTING A SLIGHT WARMUP FOR THE LATTER PART OF
THE FORECAST...GEM/EURO AND SEVERAL GFS ENSEMBLE FAMILIES ARE
SUGGESTING THAT THE COLD AIR WILL REMAIN ENTRENCHED OVER THE NORTHERN
PORTION OF THE CONUS...LEADING TO CONTINUED COLD...AND WITH THE
GREAT LAKES STILL DEVOID OF ICE AND WARM...LAKE EFFECT WILL PERSIST
ON AND OFF THROUGH THE EXTENDED PERIOD.
WESTERLY FLOW FAR ENOUGH SOUTH THAT OUR AREA WILL KEEP BEST CHANCE
OF SYNOPTIC SCALE SYSTEM-WIDE SNOW WILL BE REMAIN SOUTH...ESPECIALLY
IN THE OHIO RIVER VALLEY.
KEPT TREND OF PREVIOUS FORECASTS WITH BLENDED SOLUTION FOR THE LATER
PERIODS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1239 AM EST SUN NOV 16 2014
LOWER LEVELS FINALLY SATURATED NEAR KSBN WITH LIGHT SNOW FALLING. SHOULD
BE DONE NEAR OR JUST AFTER 06Z AS RADAR TRENDS ARE DECREASING SO
WILL CARRY A BRIEF MVFR TEMPO GROUP. OTHERWISE STAYED WITH VFR INTO
THE DAY ON SUNDAY. LATEST HRRR GUIDANCE IS SUGGESTING SOME MVFR
AND IFR CIGS DEVELOPING OVERNIGHT BUT NO SIGNS YET AND WITH VFR CLOUD
COVER IN PLACE OPTED TO HOLD OFF AND MONITOR TRENDS. NEXT SYSTEM
MOVES IN SUNDAY AFTERNOON WITH SYSTEM SNOW SPREADING EAST LATE
AFTERNOON AND ESPECIALLY AFTER 00Z. KSBN WILL BE JUST TO THE
NORTHWEST SO ONLY SOME FLURRIES OR VERY LIGHT SNOW THERE WITH NO
RESTRICTION TO VIS. KFWA WILL BE CLOSER TO DEEPER LIFT AND
MOISTURE WITH VIS DROPPING TO IFR LEVELS AFTER 00Z.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SYNOPSIS...T
SHORT TERM...STEINWEDEL
LONG TERM...LEWIS
AVIATION...LASHLEY
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
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WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS PADUCAH KY
1159 PM CST Sat Nov 15 2014
.UPDATE...
Issued at 606 PM CST SAT NOV 15 2014
Small vort along the Arkansas/Missouri border is producing some
showers which should move east during the evening. Leaned heavily
on the HRRR model for movement and location. Precip type is tricky
as we have already had sleet and rain reported with the current
light precip moving through the area. May see snow/sleet/rain
depending upon location. Do not expect much in the way of accumulation.
&&
.SHORT TERM...(Tonight through Monday night)
Issued at 315 PM CST SAT NOV 15 2014
Confidence has increased enough at this point to warrant a Winter
Weather Advisory for all except the southern Pennyrile region of
western KY for the Sunday night time frame. 12z numerical models
continue on track and in decent agreement with timing and QPF
amounts. The main question will be where the snow vs. sleet vs
rain line sets up Sunday evening, and how quickly it will sink
southeast across western KY during the night. Most models have
slowed the cooling aloft significantly enough that areas of the
southern Pennyrile may experience only rain until between midnight
and 4 AM. There may end up being an extended period of sleet over
much of the remainder of western Kentucky before going over to all
snow late in the evening. Areas along the Ohio River will likely
see a quicker transition to snow during the evening, while mostly
snow will fall at most locations north and west of there. When all
is said and done,
Most should wake Monday morning to a good inch or two of snow. The
exception may be the srn Pennyrile, where the transition is
later and more uncertain. Areas just northwest of that region may see
lighter snow totals if sleet ends up prevailing. On the other
hand, the system looks as though it will strengthen a bit as it
pulls northeast Sunday night. Because of this, am a bit concerned
that some areas up in sw IN and nw KY may end up locally closer to
4 inches. Will stick with an advisory for that region for now, and
let future shifts upgrade to warning headlines if this becomes
more apparent.
Wicked cold air for mid November is still slated to drive
southeast into the region behind the system early next week. Most
locations will not get above freezing on Monday. If we end up with
a layer of snow, lows Monday night may dip to near 10 degrees in
some locations.
.LONG TERM...(Tuesday through Saturday)
Issued at 315 PM CST SAT NOV 15 2014
GFS, ECMWF and GEM are in good agreement Monday night through
Wednesday night showing surface high pressure sliding from the
southern Plains across the Gulf Coast states. As the high moves
southeast of our region, a return of southerly flow will help the
unseasonably cold temperatures improve for Wednesday, though
readings will still be well below normal. Models show a weak dry
cold front moving across the the region late Wednesday into
Wednesday night. The wind shift will result in temperatures
dropping back off a few degrees.
For Thursday through Saturday, models diverge drastically with ECMWF
bringing a surface low moving northeast across the PAH forecast area
by 06z Friday. GFS and GEM both show a surface high over the middle
Mississippi Valley at the same time. Model ensembles lean toward
the latest ECMWF and throw in precip chances Thursday through
Saturday. Along with neighboring offices, pulled any precip chances
for Thursday, and toned back on pops a little through the rest of
the forecast. Next question is precip types. Soundings indicate
overall rain or snow, with the only deciding factor being surface
temperatures. Went rain/snow mix Thursday night through Friday
night, then just went rain on Saturday with temperatures reaching
the lower to middle 40s. Overall confidence is low with PoPs, but
believe at this point precip amounts would be minor.
&&
.AVIATION...
Issued at 1158 PM CST SAT NOV 15 2014
Initial challenge for the next 1-3 hours will be the departure of
the remaining wintry precipitation and associated visibility
restriction from MVFR to VFR.
Beyond 12z, the next system should begin to lower VFR ceilings to
MVFR at KCGI...eventually working east KEVV/KOWB by 00z Monday. As
the ceilings lower with the onset of wintry precipitation
visibilities will range from 3-5 miles. A shift to low MVFR to IFR
ceilings will take place after dark on Sunday, as the upper level
system enhances over the WFO PAH TAF sites. Anticipate lower
visibilities closer to 06z Sunday.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...WINTER WEATHER ADVISORY from 6 PM Sunday to 6 AM CST Monday FOR
ILZ075>078-080>094.
MO...WINTER WEATHER ADVISORY from 6 PM Sunday to 6 AM CST Monday FOR
MOZ076-086-087-100-107>112-114.
IN...WINTER WEATHER ADVISORY from 6 PM Sunday to 6 AM CST Monday FOR
INZ081-082-085>088.
KY...WINTER WEATHER ADVISORY from 6 PM Sunday to 6 AM CST Monday FOR
KYZ001>008-010-011-013>016-018>020.
&&
$$
UPDATE...PS
SHORT TERM...MEFFERT
LONG TERM...RST
AVIATION...Smith
AREA FORECAST DISCUSSION
NWS PADUCAH KY
1127 PM CST Sat Nov 15 2014
.MESOSCALE DISCUSSION...
Issued at 1127 PM CST SAT NOV 15 2014
An impressive forcing/lift scenario this evening, as a low
level/low amplitude shortwave (at and below 700 mb) moved through
the region with a veering wind profile working down toward the
surface. The mandatory levels at 850/925 mb showed decent warm air
advection, providing the low level lift. The increasing winds from
700 to 250 mb provided the lift aloft.
The combination of lift through the layer, combined with the
transport of low level moisture from the Gulf of Mexico and the
mid-level moisture set the stage for efficient seeder feeder
development this evening. The greater intensity of the sleet
coincided well with the lift (omega) at the mean -15 Celciu level...a
good average for efficient dendritic growth from the mid-cloud
down to the lower cloud base.
The 11-3.9 micron GOES difference channel depicted the expansive
water cloud and the upper level seeder clouds well this evening,
even hinting at an widening of coverage as the jet max moved
through the area.
For the rest of this evening and through at least 3 am CST,
anticipate the coverage of the wintry precipitation will diminish
and move southeast as the wind field and effect shear for lift
move east as well.
Adjusted the weather to reflect mainly a northern transition to
intermittent light snow/snow flurries snow from the northwest, as
the volume of ice crystals lessen and the lift weakens with time.
The warm advection closer to the stronger wind fields to the south
should maintain sleet as the primary wintry precipitation, with a
possible change over to rain along the KY/TN border between
midnight and 2 am CST.
Precipitation should diminish significantly after 3 am CST.
&&
.UPDATE...
Issued at 606 PM CST SAT NOV 15 2014
Small vort along the Arkansas/Missouri border is producing some
showers which should move east during the evening. Leaned heavily
on the HRRR model for movement and location. Precip type is tricky
as we have already had sleet and rain reported with the current
light precip moving through the area. May see snow/sleet/rain
depending upon location. Do not expect much in the way of accumulation.
&&
.SHORT TERM...(Tonight through Monday night)
Issued at 315 PM CST SAT NOV 15 2014
Confidence has increased enough at this point to warrant a Winter
Weather Advisory for all except the southern Pennyrile region of
western KY for the Sunday night time frame. 12z numerical models
continue on track and in decent agreement with timing and QPF
amounts. The main question will be where the snow vs. sleet vs
rain line sets up Sunday evening, and how quickly it will sink
southeast across western KY during the night. Most models have
slowed the cooling aloft significantly enough that areas of the
southern Pennyrile may experience only rain until between midnight
and 4 AM. There may end up being an extended period of sleet over
much of the remainder of western Kentucky before going over to all
snow late in the evening. Areas along the Ohio River will likely
see a quicker transition to snow during the evening, while mostly
snow will fall at most locations north and west of there. When all
is said and done,
Most should wake Monday morning to a good inch or two of snow. The
exception may be the srn Pennyrile, where the transition is
later and more uncertain. Areas just northwest of that region may see
lighter snow totals if sleet ends up prevailing. On the other
hand, the system looks as though it will strengthen a bit as it
pulls northeast Sunday night. Because of this, am a bit concerned
that some areas up in sw IN and nw KY may end up locally closer to
4 inches. Will stick with an advisory for that region for now, and
let future shifts upgrade to warning headlines if this becomes
more apparent.
Wicked cold air for mid November is still slated to drive
southeast into the region behind the system early next week. Most
locations will not get above freezing on Monday. If we end up with
a layer of snow, lows Monday night may dip to near 10 degrees in
some locations.
.LONG TERM...(Tuesday through Saturday)
Issued at 315 PM CST SAT NOV 15 2014
GFS, ECMWF and GEM are in good agreement Monday night through
Wednesday night showing surface high pressure sliding from the
southern Plains across the Gulf Coast states. As the high moves
southeast of our region, a return of southerly flow will help the
unseasonably cold temperatures improve for Wednesday, though
readings will still be well below normal. Models show a weak dry
cold front moving across the the region late Wednesday into
Wednesday night. The wind shift will result in temperatures
dropping back off a few degrees.
For Thursday through Saturday, models diverge drastically with ECMWF
bringing a surface low moving northeast across the PAH forecast area
by 06z Friday. GFS and GEM both show a surface high over the middle
Mississippi Valley at the same time. Model ensembles lean toward
the latest ECMWF and throw in precip chances Thursday through
Saturday. Along with neighboring offices, pulled any precip chances
for Thursday, and toned back on pops a little through the rest of
the forecast. Next question is precip types. Soundings indicate
overall rain or snow, with the only deciding factor being surface
temperatures. Went rain/snow mix Thursday night through Friday
night, then just went rain on Saturday with temperatures reaching
the lower to middle 40s. Overall confidence is low with PoPs, but
believe at this point precip amounts would be minor.
&&
.AVIATION...
Issued at 547 PM CST SAT NOV 15 2014
Main difference and challenge with the 00z Saturday WFO PAH TAF
issuance is the addition of mixed wintry precipitation within the
WFO PAH County Warning area. Initial onset of precipitation
primarily consists of light snow and sleet, changing to a mix of
rain and snow. Kept a mention of a mix through the evening hours.
Overcast VFR ceilings at or above 5Kft should dominate through the
overnight hours, with lower VFR ceilings developing ater 21z
Saturday.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...WINTER WEATHER ADVISORY from 6 PM Sunday to 6 AM CST Monday FOR
ILZ075>078-080>094.
MO...WINTER WEATHER ADVISORY from 6 PM Sunday to 6 AM CST Monday FOR
MOZ076-086-087-100-107>112-114.
IN...WINTER WEATHER ADVISORY from 6 PM Sunday to 6 AM CST Monday FOR
INZ081-082-085>088.
KY...WINTER WEATHER ADVISORY from 6 PM Sunday to 6 AM CST Monday FOR
KYZ001>008-010-011-013>016-018>020.
&&
$$
MESOSCALE...Smith
UPDATE...PS
SHORT TERM...MEFFERT
LONG TERM...RST
AVIATION...Smith
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
501 AM EST SUN NOV 16 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 420 AM EST SUN NOV 16 2014
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS AN ARCTIC BRANCH UPR
TROF CENTERED OVER HUDSON BAY DOWNSTREAM OF A RDG OVER WRN CANADA. A
SHRTWV MOVING E THRU MN IS EMBEDDED IN THE POLAR BRANCH WLY FLOW
DOMINATING THE CONUS AND BRINGING AN AREA OF LIGHT SN TO THE E HALF
OF MN...MUCH OF WI AND SCENTRAL UPR MI EARLY THIS MRNG. ALTHOUGH
THERE IS FAIRLY STRONG DPVA/DEEP LYR QVECTOR CNVGC AND SOME UPR DVGC
CONTRIBUTING TO DEEP MOISTENING ALOFT AND FORCING THIS AREA OF SN...
ONLY WEAK LLVL MSTR INFLOW THAT IS LIMITING PWAT TO NO MORE THAN
ABOUT 0.33 INCH AT GRB /85 PCT OF NORMAL/ AND H7 SPECIFIC HUMIDITY
TO NO MORE THAN ABOUT 1 G/KG IS LIMITING THE OVERALL SN INTENSITY.
SINCE H85 TEMPS ARE ABOUT -14C...THE LLVL WSW FLOW IS BRINGING SOME
LES TO THE KEWEENAW. BUT RATHER DRY NATURE OF THE LLVL AIR IN NRN MN
AS DEPICTED ON THE 00Z INL RAOB APPEARS TO BE LIMITING THE INTENSITY
OF THIS SN. LOOKING FARTHER UPSTREAM IN SCENTRAL CANADA...A VERY
STRONG SHRTWV EMBEDDED IN THE NW ARCTIC BRANCH FLOW IS DIGGING SEWD
NEAR LK WINNIPEG.
MAIN FCST CONCERNS IN THE SHORT TERM ARE SN TRENDS/AMOUNTS OVER
MAINLY THE SE HALF OF THE CWA ASSOCIATED WITH DISTURBANCE THAT WL BE
MOVING THRU WI. FOCUS FOR LATER TNGT SHIFTS TO POTENTIAL FOR MORE SN
OVER MAINLY THE W IN ADVANCE OF SHRTWV NOW NEAR LK WINNIPEG.
TODAY...THE SHRTWV IN MN EARLY THIS MRNG IS PROGGED TO MOVE STEADILY
ENEWD INTO NRN LOWER MI BY 18Z AND THEN INTO SE ONTARIO DURING THE
AFTN. AREA OF DPVA/DEEP LYR QVECTOR CNVGC/UPR DVGC IS FCST TO IMPACT
THE SE CWA THIS MRNG BEFORE EXITING BY 18Z AND GIVING WAY TO SOME
FAIRLY VIGOROUS DNVA/DEEP LYR QVECTOR DVGC. SINCE THE UPR FLOW IS
TENDING TO BACK MORE IN ADVANCE OF THE DIGGING SHRTWV IN SCENTRAL
CANADA AND MODEL TRENDS SHOW THE DYNAMIC FORCING SHIFTED FARTHER TO
THE N AND RADAR TRENDS/SFC OBS INDICATE THE SN AREA IS MOVING
FARTHER TO THE N...INCRSD POPS OVER AREA S OF A LINE FM ABOUT
IRONWOOD TO MARQUETTE. BUT MODEL QPF IS ONLY A COUPLE HUNDREDTHS OF
AN INCH...SO ANY SN ACCUM WL BE ON THE LIGHT SIDE WITH LIMITED
ABSOLUTE MSTR AND POOR SN GROWTH GIVEN ELEVATED AREA OF FORCING WELL
ABOVE LOWER DGZ. THE LARGER SCALE PCPN WL END BY 18Z FOLLOWING THE
EXIT OF THE DYNAMIC SUPPORT. SINCE THE LLVL FLOW IS FCST TO BACK
SLOWLY BUT STEADILY THRU THE DAY IN ADVANCE OF SHRTWV DIGGING SEWD
TOWARD NW MN...EXPECT THE LES OVER THE KEWEENAW EARLY THIS MRNG TO
SHIFT OUT INTO LK SUP. FOR THE MOST PART...THE HIER RES MODELS
INDICATE THE LLVL FLOW WL NOT BACK ENUF TO BRING MUCH IF ANY LES INTO
LUCE/SCHOOLCRAFT COUNTIES TODAY. BUT WL MAINTAIN SOME CHC POPS OVER
THE SE PORTIONS OF THESE COUNTIES LATE TO REFLECT UNCERTAINTY.
OTRW...DESPITE THE MID LVL DRYING/SUBSIDENCE...THE BACKING LLVL FLOW
WL ALLOW SOME LO CLDS IN WI TO MOVE INTO UPR MI...LIMITING THE
POTENTIAL FOR MORE SUNSHINE. THE BEST CHANCE FOR MORE SUNSHINE WL BE
NEAR LK SUP...WHERE THE LLVL SW FLOW WL DOWNSLOPE.
TNGT...AS THE SHRTWV TO THE NW DIGS SEWD TOWARD NW LK SUP AND CLOSES
OFF BY 12Z MON...BAND OF DEEP LYR QVECTOR CNVGC IN THE MSTR STARVED
COMMA TAIL OF THIS FEATURE IS FCST TO SWING ACROSS UPR MI. ONCE
AGAIN...AN ABSENCE OF SGFNT LLVL MOISTENING WL BE AN IMPEDIMENT TO
WIDESPREAD LIGHT SN. THE BEST CHC FOR MORE WIDESPREAD SN WL BE LATE
OVER THE W...WHERE THE COLD FNT/ENHANCED LLVL CNVGC ASSOCIATED WITH
THE SHRTWV WL ARRIVE LATE. ALSO MAINTAINED SOMEWHAT HIER POPS TO THE
E OF MANISTIQUE-NEWBERRY TO ACCOUNT FOR THE POTENTIAL OF SOME LES
OFF LK MI AS THE INCOMING DYNAMICS COINCIDE WITH A LLVL FLOW BACKED
SUFFICIENTLY TO THE SSW FOR SOME LK EFFECT ESPECIALLY IN THE EVNG.
ONCE THIS COMMA TAIL RIBBON OF FORCING PASSES TO THE E LATE...THE
WINDS MAY VEER ENUF TO DIMINISH THIS POTENTIAL OVER THE E.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 349 AM EST SUN NOV 16 2014
A LOW CURRENTLY TO THE NORTHEAST OF LAKE WINNIPEG WILL DROP
SOUTHEAST OVER LAKE SUPERIOR TONIGHT AND BE THE KEY FEATURE IN
BRINGING ANOTHER SHOT OF COLD AIR ALONG WITH A PERIOD OF LAKE EFFECT
SNOW TO THE AREA FOR MONDAY AND TUESDAY.
THERE WILL LIKELY BE A FEW LIGHT SNOW SHOWERS OVER THE WESTERN U.P.
IN ASSOCIATION WITH THE LOW MOVING THROUGH THE AREA AND JUST AHEAD
OF THE SURFACE TROUGH OVER WESTERN LAKE SUPERIOR AND STARTING TO
COME ONSHORE AT 12Z. AS THIS THIS PUSHES THROUGH...WINDS WILL SHIFT
AROUND TO THE NORTHWEST AND LEAD TO STEADILY INCREASING LAKE EFFECT
(DELTA-T VALUES ABOVE 20) OVER THE WESTERN CWA DURING THE MORNING.
DEEP MOISTURE ASSOCIATED WITH THE LOW WILL REALLY SURGE INTO THE
AREA MONDAY AFTERNOON AND REMAIN THROUGH MONDAY NIGHT OVER THE WEST
AND TUESDAY MORNING OVER THE EAST. THE COOLING ALOFT AND DEEP
MOISTURE WILL ALLOW FOR THE LAKE EFFECT SNOW SHOWERS TO UTILIZE THE
LAKE INDUCED EQUILIBRIUM LEVELS IN THE 15-17KFT RANGE. THUS...WOULD
EXPECT THE LAKE EFFECT TO REALLY INCREASE IN THE AFTERNOON OVER THE
WEST HALF. WITH PLENTY OF UPWARD MOTION (LAKE INDUCED CAPE VALUES OF
700-800 J/KG) AND THE PREVIOUSLY MENTIONED MOISTURE/EQL VALUES
SHOULD SUPPORT MODERATE TO HEAVY LAKE EFFECT SNOW. PLUS...WITH A
GOOD PORTION OF THE LOW LEVEL FORCING RIGHT IN THE DGZ...WOULD
EXPECT THE SNOW RATIOS TO BE IN THE LOW-MID 20S (HELD DOWN SOME FROM
THE TRADITIONALLY HIGHER VALUES DUE TO THE STRENGTH OF THE WINDS).
THE FAVORABLE PERIOD OF LAKE EFFECT WILL CONTINUE INTO THE EVENING
AND LEAD TO SNOWFALL AMOUNTS THE SNOWBELTS OVER THE WEST IN THE 5
TO 11 INCH RANGE BY MIDNIGHT MONDAY NIGHT. EXPECT THE SNOW TO
DIMINISH HEADING INTO THE OVERNIGHT HOURS AS THE DEEPER MOISTURE
DEPARTS...BUT STILL SHOULD SEE LIGHT TO MODERATE SNOWFALL INTO
TUESDAY MORNING WITH SNOW RATIOS HELPED BY WEAKER WINDS AND ALL OF
THE CLOUD BEING IN THE DGZ.
THE STRONG LAKE EFFECT/ENHANCED SNOW SHOWERS WILL SHIFT EAST THROUGH
THE AFTERNOON/EVENING INTO NORTH CENTRAL AND EVENTUALLY EASTERN
UPPER MICHIGAN BEHIND THE SURFACE TROUGH. 00Z RUNS LOOK TO HAVE SPED
UP THE ARRIVAL OF THE CONVERGENT BAND OF LAKE ENHANCED SNOW OVER THE
NORTH CENTRAL AND HAVE FOLLOWED THAT IDEA FOR POPS/SNOWFALL MONDAY
NIGHT. MARQUETTE COUNTY WILL BE INTERESTING SINCE THE WIND PROFILE
WOULD SUPPORT NORTH WIND LES AT 850MB AND NORTH-NORTHWEST IN THE
LOWER LEVELS ON MONDAY EVENING BEFORE TRANSITIONING TO GENERALLY
NORTHWEST LAKE EFFECT BY TUESDAY MORNING. THAT NNW WIND DIRECTION
WOULD SUPPORT THE BANDS GINNING INTO THE HIGHER TERRAIN AREAS AND
AIDING SNOWFALL TOTALS. THE CYCLONIC FLOW BEHIND THE LOW WILL
TRANSITION THE LES INTO WESTERN ALGER COUNTY AND WITH COASTAL
CONVERGENCE ALONG THE MARQUETTE COUNTY SHORELINE...WOULD EXPECT
HEAVY LAKE EFFECT SNOW THERE AFTER MIDNIGHT MONDAY NIGHT AND
CONTINUING THROUGH AT LEAST TUESDAY MORNING. THE STRENGTH OF THE
WINDS SHOULD CARRY THE LAKE EFFECT WELL INLAND OVER EAST-CENTRAL
UPPER MICHIGAN...WITH AT LEAST A FEW INCHES OF ACCUMULATION POSSIBLE
IN EASTERN DELTA AND SOUTHWEST SCHOOLCRAFT COUNTIES. FOR MARQUETTE
AND WESTERN ALGER COUNTIES...EXPECT 24HR SNOWFALL TOTALS (MONDAY
AFTERNOON THROUGH TUESDAY MORNING) IN THE 5 TO 11 INCH RANGE
ALSO...WITH THE HIGHEST VALUES OVER THE HURON MOUNTAINS AND WESTERN
ALGER COUNTY. WHILE CONDITIONS BECOME LESS FAVORABLE ON TUESDAY WITH
INVERSION HEIGHTS LOWERING AHEAD OF THE UPPER RIDGE...THE LAKE
FORCING WILL REMAIN IN THE DGZ AND ENABLE THE POTENTIAL FOR SOME
VERY FLUFFY ACCUMULATION AS WINDS BACK TO THE WEST AND EVENTUALLY
SOUTHWEST.
SO HOW TO HANDLE THE POTENTIAL HEADLINES. WILL ISSUE A LAKE
EFFECT SNOW WATCH FOR GOGEBIC/ONTONAGON...NRN. HOUGHTON AND
KEWEENAW COUNTY DUE TO THE EXPECTED IMPACTS MONDAY INTO MONDAY
NIGHT. ALTHOUGH SNOWFALL AMOUNTS WILL LIKELY BE MORE IN THE
ADVISORY RANGE OVER THE KEWEENAW...THOUGHT THE WIND GUSTS IN THE
35-40MPH RANGE WOULD CREATE ENOUGH BLOWING SNOW TO INCLUDE THEM IN
THE WATCH. GOGEBIC/ONTONAGON WILL SEE SLIGHTLY LOWER WINDS BUT A
BETTER OPPORTUNITY TO SEE WARNING SNOWFALL. AS FOR FARTHER
EAST...THINGS GET A LITTLE MORE COMPLICATED. THINK BARAGA/MARQUETTE
ARE SOLID LES ADVISORIES...BUT BELIEVE WESTERN ALGER COUNTY WILL
SEE WARNING SNOWFALL ON MONDAY NIGHT. DEBATED ISSUING A WATCH FOR
ALGER...ESPECIALLY WITH THE ADDED WIND FACTOR...BUT WAS CONCERNED
THERE WOULD BE ASSUMPTIONS MADE THAT MARQUETTE/BARAGA WOULDN/T
EXPERIENCE ANY IMPACTS SINCE THEY WEREN/T IN A WATCH (EVEN THOUGH
THEY WOULD SUPPORT HAVING AN ADVISORY). THEREFORE...HAVE LEFT OUT
FOR NOW...WHICH WILL ALLOW THE DAY SHIFT TO CONVERT THE WATCH OVER
THE WEST TO WARNING/ADVISORY AND START THE ADVISORY TRANSITION TO
THE EAST FOR SOME OF THE OTHER COUNTIES. AT THAT POINT A WATCH
COULD BE ISSUED.
THE UPPER TROUGH DRIVING THIS PERIOD OF COLD AND LAKE EFFECT WILL
SHIFT TO THE EAST ON TUESDAY AFTERNOON/NIGHT...ALLOWING A WEAK HIGH
PRESSURE RIDGE TO BUILD OVER THE AREA FOR TUESDAY NIGHT.
THUS...WOULD EXPECT THE LAKE EFFECT TO TRANSITION TO THE WESTERLY
OR EVEN SOUTHWESTERLY WIND FAVORED LOCATIONS (KEWEENAW AND ALONG THE
LAKE SUPERIOR SHORELINE EAST OF GRAND MARAIS) AS WINDS BACK. ANOTHER
SHORTWAVE DIVING SOUTHEAST THROUGH CENTRAL CANADA ON TUESDAY WILL
DROP INTO THE UPPER GREAT LAKES REGION LATE TUESDAY NIGHT...BRINGING
ANOTHER SURFACE TROUGH THROUGH THE REGION AND USHERING IN COLD AIR
AND LAKE EFFECT FOR WEDNESDAY INTO THURSDAY. WILL LIKELY SEE SOME
SYNOPTIC SNOWFALL WITH THIS SHORTWAVE...BUT GENERALLY A DUSTING TO
AN INCH OF SNOW NEAR THE WISCONSIN BORDER. BEHIND THIS
TROUGH...EXPECT LAKE EFFECT TO OCCUR IN THE WEST-NORTHWEST FAVORED
LOCATIONS. THERE ARE SOME HINTS OF A LINGERING SURFACE TROUGH
DROPPING SOUTHEAST ACROSS EASTERN LAKE SUPERIOR LATE WEDNESDAY
NIGHT...WHICH WOULD SWITCH WINDS TO MORE OF A NORTHWEST OR
NORTH-NORTHWEST DIRECTION OVER THE EAST. OVERALL...LOOKS LIKE LAKE
EFFECT PARAMETERS ON WEDNESDAY NIGHT AND THURSDAY WILL BE SIMILAR TO
THE BEGINNING OF THE WORK WEEK AND LEAD TO THE POTENTIAL FOR ANOTHER
MODERATE-HEAVY LAKE EFFECT SNOW NEAR LAKE SUPERIOR. WILL CONTINUE
TO MENTION THIS PERIOD IN THE HWO/EHWO.
FRIDAY AND SATURDAY...THE UPPER TROUGH AFFECTING THE AREA
WEDNESDAY/THURSDAY WILL SHIFT EAST AND OUT OF THE AREA ON FRIDAY.
THIS WILL LEAD TO TEMPERATURES TRYING TO WARM TOWARDS NORMAL AS A
WEAK UPPER RIDGE MOVES OVER THE AREA. A SURFACE HIGH WILL BRUSH THE
AREA ON FRIDAY KEEPING LAKE EFFECT CONFINED TO THE WESTERLY WIND
LOCATIONS. THERE ARE HINTS IN SOME OF THE MODELS OF A WEAK
DISTURBANCE AFFECTING THE AREA ON FRIDAY NIGHT INTO SATURDAY...BUT
CONFIDENCE IS LOW AT THIS TIME.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1139 PM EST SAT NOV 15 2014
WESTERLY WINDS AND SUFFICIENTLY COLD AIR FLOWING ACROSS LAKE
SUPERIOR WILL LEAD TO OCNL MVFR CONDITIONS IN -SHSN/FLURRIES AT KCMX
FOR THE NEXT FEW HRS. LATER IN THE NIGHT...LOW-LEVEL WINDS SHOULD
BACK TOWARD THE SW JUST ENOUGH TO PUSH LAKE EFFECT SNOW SHOWERS/MVFR
CONDITIONS TO THE N OF THE TERMINAL. VFR CONDITIONS SHOULD THEN
CONTINUE AT KCMX THRU THE END THIS FCST PERIOD. AT KIWD/KSAW...VFR
CONDITIONS SHOULD GENERALLY PREVAIL WITH THE EXCEPTION OF A PERIOD
OF MVFR CIGS AND PERHAPS SOME -SN/FLURRIES LATE IN THE NIGHT AND
INTO THE MORNING AS A DISTURBANCE MOVES ACROSS THE WRN GREAT LAKES
REGION. MVFR CONDITIONS MAY REDEVELOP NEAR THE END OF THE FCST
PERIOD AT KIWD AS THE NEXT DISTURBANCE APPROACHES.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 349 AM EST SUN NOV 16 2014
SOUTHWEST WINDS UP TO 30KTS WILL CONTINUE TODAY AHEAD OF A LOW
PRESSURE SYSTEM JUST TO THE EAST OF LAKE WINNIPEG. THIS SYSTEM WILL
DROP SOUTHEAST AND OVER LAKE SUPERIOR TONIGHT AND THEN SLOWLY EXIT
TO THE EAST ON MONDAY. AS A TROUGH ASSOCIATED WITH THE LOW SWEEPS
ACROSS THE LAKE ON MONDAY...COLD AIR SURGING ACROSS THE RELATIVELY
WARM WATERS OF LAKE SUPERIOR WILL LEAD TO THE POTENTIAL FOR
NORTHWEST GALE FORCE WINDS OF 35 TO 40KTS MONDAY AFTERNOON INTO
TUESDAY MORNING OVER MUCH OF LAKE SUPERIOR. WILL ISSUE A GALE
WATCH TO ACCOUNT FOR THE EXPECTED GALES...SPREADING FROM WEST TO
EAST MONDAY AFTERNOON/EVENING. WINDS WILL GRADUALLY DECREASE TUESDAY
AFTERNOON INTO TUESDAY NIGHT AS A WEAK HIGH PRESSURE RIDGE MOVES
ACROSS THE AREA. ANOTHER TROUGH WILL SWEEP SOUTHEAST ACROSS THE
UPPER GREAT LAKES REGION WEDNESDAY MORNING AND BRING AN INCREASE IN
WINDS OUT OF THE NORTHWEST (UP TO 30KTS) WHICH WILL CONTINUE INTO
THURSDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW WATCH FROM MONDAY MORNING THROUGH TUESDAY
MORNING FOR MIZ001>003-009.
LAKE SUPERIOR...
GALE WATCH FROM LATE MONDAY NIGHT THROUGH TUESDAY AFTERNOON FOR
LSZ267.
GALE WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY AFTERNOON FOR
LSZ265-266.
GALE WATCH FROM MONDAY AFTERNOON THROUGH LATE MONDAY NIGHT FOR
LSZ162.
GALE WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY MORNING FOR
LSZ242>245-263-264.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...SRF
AVIATION...ROLFSON
MARINE...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
420 AM EST SUN NOV 16 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 420 AM EST SUN NOV 16 2014
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS AN ARCTIC BRANCH UPR
TROF CENTERED OVER HUDSON BAY DOWNSTREAM OF A RDG OVER WRN CANADA. A
SHRTWV MOVING E THRU MN IS EMBEDDED IN THE POLAR BRANCH WLY FLOW
DOMINATING THE CONUS AND BRINGING AN AREA OF LIGHT SN TO THE E HALF
OF MN...MUCH OF WI AND SCENTRAL UPR MI EARLY THIS MRNG. ALTHOUGH
THERE IS FAIRLY STRONG DPVA/DEEP LYR QVECTOR CNVGC AND SOME UPR DVGC
CONTRIBUTING TO DEEP MOISTENING ALOFT AND FORCING THIS AREA OF SN...
ONLY WEAK LLVL MSTR INFLOW THAT IS LIMITING PWAT TO NO MORE THAN
ABOUT 0.33 INCH AT GRB /85 PCT OF NORMAL/ AND H7 SPECIFIC HUMIDITY
TO NO MORE THAN ABOUT 1 G/KG IS LIMITING THE OVERALL SN INTENSITY.
SINCE H85 TEMPS ARE ABOUT -14C...THE LLVL WSW FLOW IS BRINGING SOME
LES TO THE KEWEENAW. BUT RATHER DRY NATURE OF THE LLVL AIR IN NRN MN
AS DEPICTED ON THE 00Z INL RAOB APPEARS TO BE LIMITING THE INTENSITY
OF THIS SN. LOOKING FARTHER UPSTREAM IN SCENTRAL CANADA...A VERY
STRONG SHRTWV EMBEDDED IN THE NW ARCTIC BRANCH FLOW IS DIGGING SEWD
NEAR LK WINNIPEG.
MAIN FCST CONCERNS IN THE SHORT TERM ARE SN TRENDS/AMOUNTS OVER
MAINLY THE SE HALF OF THE CWA ASSOCIATED WITH DISTURBANCE THAT WL BE
MOVING THRU WI. FOCUS FOR LATER TNGT SHIFTS TO POTENTIAL FOR MORE SN
OVER MAINLY THE W IN ADVANCE OF SHRTWV NOW NEAR LK WINNIPEG.
TODAY...THE SHRTWV IN MN EARLY THIS MRNG IS PROGGED TO MOVE STEADILY
ENEWD INTO NRN LOWER MI BY 18Z AND THEN INTO SE ONTARIO DURING THE
AFTN. AREA OF DPVA/DEEP LYR QVECTOR CNVGC/UPR DVGC IS FCST TO IMPACT
THE SE CWA THIS MRNG BEFORE EXITING BY 18Z AND GIVING WAY TO SOME
FAIRLY VIGOROUS DNVA/DEEP LYR QVECTOR DVGC. SINCE THE UPR FLOW IS
TENDING TO BACK MORE IN ADVANCE OF THE DIGGING SHRTWV IN SCENTRAL
CANADA AND MODEL TRENDS SHOW THE DYNAMIC FORCING SHIFTED FARTHER TO
THE N AND RADAR TRENDS/SFC OBS INDICATE THE SN AREA IS MOVING
FARTHER TO THE N...INCRSD POPS OVER AREA S OF A LINE FM ABOUT
IRONWOOD TO MARQUETTE. BUT MODEL QPF IS ONLY A COUPLE HUNDREDTHS OF
AN INCH...SO ANY SN ACCUM WL BE ON THE LIGHT SIDE WITH LIMITED
ABSOLUTE MSTR. THE LARGER SCALE PCPN WL END BY 18Z FOLLOWING THE
EXIT OF THE DYNAMIC SUPPORT. SINCE THE LLVL FLOW IS FCST TO BACK
SLOWLY BUT STEADILY THRU THE DAY IN ADVANCE OF SHRTWV DIGGING SEWD
TOWARD NW MN...EXPECT THE LES OVER THE KEWEENAW EARLY THIS MRNG TO
SHIFT OUT INTO LK SUP. FOR THE MOST PART...THE HIER RES MODELS
INDICATE THE LLVL FLOW WL NOT BACK ENUF TO BRING MUCH IF ANY LES
INTO LUCE/SCHOOLCRAFT COUNTIES TODAY. BUT WL MAINTAIN SOME CHC POPS
OVER THE SE PORTIONS OF THESE COUNTIES LATE TO REFLECT UNCERTAINTY.
OTRW...DESPITE THE MID LVL DRYING/SUBSIDENCE...THE BACKING LLVL FLOW
WL ALLOW SOME LO CLDS IN WI TO MOVE INTO UPR MI...LIMITING THE
POTENTIAL FOR MORE SUNSHINE. THE BEST CHANCE FOR MORE SUNSHINE WL BE
NEAR LK SUP...WHERE THE LLVL SW FLOW WL DOWNSLOPE.
TNGT...AS THE SHRTWV TO THE NW DIGS SEWD TOWARD NW LK SUP AND CLOSES
OFF BY 12Z MON...BAND OF DEEP LYR QVECTOR CNVGC IN THE MSTR STARVED
COMMA TAIL OF THIS FEATURE IS FCST TO SWING ACROSS UPR MI. ONCE
AGAIN...AN ABSENCE OF SGFNT LLVL MOISTENING WL BE AN IMPEDIMENT TO
WIDESPREAD LIGHT SN. THE BEST CHC FOR MORE WIDESPREAD SN WL BE LATE
OVER THE W...WHERE THE COLD FNT/ENHANCED LLVL CNVGC ASSOCIATED WITH
THE SHRTWV WL ARRIVE LATE. ALSO MAINTAINED SOMEWHAT HIER POPS TO THE
E OF MANISTIQUE-NEWBERRY TO ACCOUNT FOR THE POTENTIAL OF SOME LES
OFF LK MI AS THE INCOMING DYNAMICS COINCIDE WITH A LLVL FLOW BACKED
SUFFICIENTLY TO THE SSW FOR SOME LK EFFECT ESPECIALLY IN THE EVNG.
ONCE THIS COMMA TAIL RIBBON OF FORCING PASSES TO THE E LATE...THE
WINDS MAY VEER ENUF TO DIMINISH THIS POTENTIAL OVER THE E.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 349 AM EST SUN NOV 16 2014
A LOW CURRENTLY TO THE NORTHEAST OF LAKE WINNIPEG WILL DROP
SOUTHEAST OVER LAKE SUPERIOR TONIGHT AND BE THE KEY FEATURE IN
BRINGING ANOTHER SHOT OF COLD AIR ALONG WITH A PERIOD OF LAKE EFFECT
SNOW TO THE AREA FOR MONDAY AND TUESDAY.
THERE WILL LIKELY BE A FEW LIGHT SNOW SHOWERS OVER THE WESTERN U.P.
IN ASSOCIATION WITH THE LOW MOVING THROUGH THE AREA AND JUST AHEAD
OF THE SURFACE TROUGH OVER WESTERN LAKE SUPERIOR AND STARTING TO
COME ONSHORE AT 12Z. AS THIS THIS PUSHES THROUGH...WINDS WILL SHIFT
AROUND TO THE NORTHWEST AND LEAD TO STEADILY INCREASING LAKE EFFECT
(DELTA-T VALUES ABOVE 20) OVER THE WESTERN CWA DURING THE MORNING.
DEEP MOISTURE ASSOCIATED WITH THE LOW WILL REALLY SURGE INTO THE
AREA MONDAY AFTERNOON AND REMAIN THROUGH MONDAY NIGHT OVER THE WEST
AND TUESDAY MORNING OVER THE EAST. THE COOLING ALOFT AND DEEP
MOISTURE WILL ALLOW FOR THE LAKE EFFECT SNOW SHOWERS TO UTILIZE THE
LAKE INDUCED EQUILIBRIUM LEVELS IN THE 15-17KFT RANGE. THUS...WOULD
EXPECT THE LAKE EFFECT TO REALLY INCREASE IN THE AFTERNOON OVER THE
WEST HALF. WITH PLENTY OF UPWARD MOTION (LAKE INDUCED CAPE VALUES OF
700-800 J/KG) AND THE PREVIOUSLY MENTIONED MOISTURE/EQL VALUES
SHOULD SUPPORT MODERATE TO HEAVY LAKE EFFECT SNOW. PLUS...WITH A
GOOD PORTION OF THE LOW LEVEL FORCING RIGHT IN THE DGZ...WOULD
EXPECT THE SNOW RATIOS TO BE IN THE LOW-MID 20S (HELD DOWN SOME FROM
THE TRADITIONALLY HIGHER VALUES DUE TO THE STRENGTH OF THE WINDS).
THE FAVORABLE PERIOD OF LAKE EFFECT WILL CONTINUE INTO THE EVENING
AND LEAD TO SNOWFALL AMOUNTS THE SNOWBELTS OVER THE WEST IN THE 5
TO 11 INCH RANGE BY MIDNIGHT MONDAY NIGHT. EXPECT THE SNOW TO
DIMINISH HEADING INTO THE OVERNIGHT HOURS AS THE DEEPER MOISTURE
DEPARTS...BUT STILL SHOULD SEE LIGHT TO MODERATE SNOWFALL INTO
TUESDAY MORNING WITH SNOW RATIOS HELPED BY WEAKER WINDS AND ALL OF
THE CLOUD BEING IN THE DGZ.
THE STRONG LAKE EFFECT/ENHANCED SNOW SHOWERS WILL SHIFT EAST THROUGH
THE AFTERNOON/EVENING INTO NORTH CENTRAL AND EVENTUALLY EASTERN
UPPER MICHIGAN BEHIND THE SURFACE TROUGH. 00Z RUNS LOOK TO HAVE SPED
UP THE ARRIVAL OF THE CONVERGENT BAND OF LAKE ENHANCED SNOW OVER THE
NORTH CENTRAL AND HAVE FOLLOWED THAT IDEA FOR POPS/SNOWFALL MONDAY
NIGHT. MARQUETTE COUNTY WILL BE INTERESTING SINCE THE WIND PROFILE
WOULD SUPPORT NORTH WIND LES AT 850MB AND NORTH-NORTHWEST IN THE
LOWER LEVELS ON MONDAY EVENING BEFORE TRANSITIONING TO GENERALLY
NORTHWEST LAKE EFFECT BY TUESDAY MORNING. THAT NNW WIND DIRECTION
WOULD SUPPORT THE BANDS GINNING INTO THE HIGHER TERRAIN AREAS AND
AIDING SNOWFALL TOTALS. THE CYCLONIC FLOW BEHIND THE LOW WILL
TRANSITION THE LES INTO WESTERN ALGER COUNTY AND WITH COASTAL
CONVERGENCE ALONG THE MARQUETTE COUNTY SHORELINE...WOULD EXPECT
HEAVY LAKE EFFECT SNOW THERE AFTER MIDNIGHT MONDAY NIGHT AND
CONTINUING THROUGH AT LEAST TUESDAY MORNING. THE STRENGTH OF THE
WINDS SHOULD CARRY THE LAKE EFFECT WELL INLAND OVER EAST-CENTRAL
UPPER MICHIGAN...WITH AT LEAST A FEW INCHES OF ACCUMULATION POSSIBLE
IN EASTERN DELTA AND SOUTHWEST SCHOOLCRAFT COUNTIES. FOR MARQUETTE
AND WESTERN ALGER COUNTIES...EXPECT 24HR SNOWFALL TOTALS (MONDAY
AFTERNOON THROUGH TUESDAY MORNING) IN THE 5 TO 11 INCH RANGE
ALSO...WITH THE HIGHEST VALUES OVER THE HURON MOUNTAINS AND WESTERN
ALGER COUNTY. WHILE CONDITIONS BECOME LESS FAVORABLE ON TUESDAY WITH
INVERSION HEIGHTS LOWERING AHEAD OF THE UPPER RIDGE...THE LAKE
FORCING WILL REMAIN IN THE DGZ AND ENABLE THE POTENTIAL FOR SOME
VERY FLUFFY ACCUMULATION AS WINDS BACK TO THE WEST AND EVENTUALLY
SOUTHWEST.
SO HOW TO HANDLE THE POTENTIAL HEADLINES. WILL ISSUE A LAKE
EFFECT SNOW WATCH FOR GOGEBIC/ONTONAGON...NRN. HOUGHTON AND
KEWEENAW COUNTY DUE TO THE EXPECTED IMPACTS MONDAY INTO MONDAY
NIGHT. ALTHOUGH SNOWFALL AMOUNTS WILL LIKELY BE MORE IN THE
ADVISORY RANGE OVER THE KEWEENAW...THOUGHT THE WIND GUSTS IN THE
35-40MPH RANGE WOULD CREATE ENOUGH BLOWING SNOW TO INCLUDE THEM IN
THE WATCH. GOGEBIC/ONTONAGON WILL SEE SLIGHTLY LOWER WINDS BUT A
BETTER OPPORTUNITY TO SEE WARNING SNOWFALL. AS FOR FARTHER
EAST...THINGS GET A LITTLE MORE COMPLICATED. THINK BARAGA/MARQUETTE
ARE SOLID LES ADVISORIES...BUT BELIEVE WESTERN ALGER COUNTY WILL
SEE WARNING SNOWFALL ON MONDAY NIGHT. DEBATED ISSUING A WATCH FOR
ALGER...ESPECIALLY WITH THE ADDED WIND FACTOR...BUT WAS CONCERNED
THERE WOULD BE ASSUMPTIONS MADE THAT MARQUETTE/BARAGA WOULDN/T
EXPERIENCE ANY IMPACTS SINCE THEY WEREN/T IN A WATCH (EVEN THOUGH
THEY WOULD SUPPORT HAVING AN ADVISORY). THEREFORE...HAVE LEFT OUT
FOR NOW...WHICH WILL ALLOW THE DAY SHIFT TO CONVERT THE WATCH OVER
THE WEST TO WARNING/ADVISORY AND START THE ADVISORY TRANSITION TO
THE EAST FOR SOME OF THE OTHER COUNTIES. AT THAT POINT A WATCH
COULD BE ISSUED.
THE UPPER TROUGH DRIVING THIS PERIOD OF COLD AND LAKE EFFECT WILL
SHIFT TO THE EAST ON TUESDAY AFTERNOON/NIGHT...ALLOWING A WEAK HIGH
PRESSURE RIDGE TO BUILD OVER THE AREA FOR TUESDAY NIGHT.
THUS...WOULD EXPECT THE LAKE EFFECT TO TRANSITION TO THE WESTERLY
OR EVEN SOUTHWESTERLY WIND FAVORED LOCATIONS (KEWEENAW AND ALONG THE
LAKE SUPERIOR SHORELINE EAST OF GRAND MARAIS) AS WINDS BACK. ANOTHER
SHORTWAVE DIVING SOUTHEAST THROUGH CENTRAL CANADA ON TUESDAY WILL
DROP INTO THE UPPER GREAT LAKES REGION LATE TUESDAY NIGHT...BRINGING
ANOTHER SURFACE TROUGH THROUGH THE REGION AND USHERING IN COLD AIR
AND LAKE EFFECT FOR WEDNESDAY INTO THURSDAY. WILL LIKELY SEE SOME
SYNOPTIC SNOWFALL WITH THIS SHORTWAVE...BUT GENERALLY A DUSTING TO
AN INCH OF SNOW NEAR THE WISCONSIN BORDER. BEHIND THIS
TROUGH...EXPECT LAKE EFFECT TO OCCUR IN THE WEST-NORTHWEST FAVORED
LOCATIONS. THERE ARE SOME HINTS OF A LINGERING SURFACE TROUGH
DROPPING SOUTHEAST ACROSS EASTERN LAKE SUPERIOR LATE WEDNESDAY
NIGHT...WHICH WOULD SWITCH WINDS TO MORE OF A NORTHWEST OR
NORTH-NORTHWEST DIRECTION OVER THE EAST. OVERALL...LOOKS LIKE LAKE
EFFECT PARAMETERS ON WEDNESDAY NIGHT AND THURSDAY WILL BE SIMILAR TO
THE BEGINNING OF THE WORK WEEK AND LEAD TO THE POTENTIAL FOR ANOTHER
MODERATE-HEAVY LAKE EFFECT SNOW NEAR LAKE SUPERIOR. WILL CONTINUE
TO MENTION THIS PERIOD IN THE HWO/EHWO.
FRIDAY AND SATURDAY...THE UPPER TROUGH AFFECTING THE AREA
WEDNESDAY/THURSDAY WILL SHIFT EAST AND OUT OF THE AREA ON FRIDAY.
THIS WILL LEAD TO TEMPERATURES TRYING TO WARM TOWARDS NORMAL AS A
WEAK UPPER RIDGE MOVES OVER THE AREA. A SURFACE HIGH WILL BRUSH THE
AREA ON FRIDAY KEEPING LAKE EFFECT CONFINED TO THE WESTERLY WIND
LOCATIONS. THERE ARE HINTS IN SOME OF THE MODELS OF A WEAK
DISTURBANCE AFFECTING THE AREA ON FRIDAY NIGHT INTO SATURDAY...BUT
CONFIDENCE IS LOW AT THIS TIME.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1139 PM EST SAT NOV 15 2014
WESTERLY WINDS AND SUFFICIENTLY COLD AIR FLOWING ACROSS LAKE
SUPERIOR WILL LEAD TO OCNL MVFR CONDITIONS IN -SHSN/FLURRIES AT KCMX
FOR THE NEXT FEW HRS. LATER IN THE NIGHT...LOW-LEVEL WINDS SHOULD
BACK TOWARD THE SW JUST ENOUGH TO PUSH LAKE EFFECT SNOW SHOWERS/MVFR
CONDITIONS TO THE N OF THE TERMINAL. VFR CONDITIONS SHOULD THEN
CONTINUE AT KCMX THRU THE END THIS FCST PERIOD. AT KIWD/KSAW...VFR
CONDITIONS SHOULD GENERALLY PREVAIL WITH THE EXCEPTION OF A PERIOD
OF MVFR CIGS AND PERHAPS SOME -SN/FLURRIES LATE IN THE NIGHT AND
INTO THE MORNING AS A DISTURBANCE MOVES ACROSS THE WRN GREAT LAKES
REGION. MVFR CONDITIONS MAY REDEVELOP NEAR THE END OF THE FCST
PERIOD AT KIWD AS THE NEXT DISTURBANCE APPROACHES.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 349 AM EST SUN NOV 16 2014
SOUTHWEST WINDS UP TO 30KTS WILL CONTINUE TODAY AHEAD OF A LOW
PRESSURE SYSTEM JUST TO THE EAST OF LAKE WINNIPEG. THIS SYSTEM WILL
DROP SOUTHEAST AND OVER LAKE SUPERIOR TONIGHT AND THEN SLOWLY EXIT
TO THE EAST ON MONDAY. AS A TROUGH ASSOCIATED WITH THE LOW SWEEPS
ACROSS THE LAKE ON MONDAY...COLD AIR SURGING ACROSS THE RELATIVELY
WARM WATERS OF LAKE SUPERIOR WILL LEAD TO THE POTENTIAL FOR
NORTHWEST GALE FORCE WINDS OF 35 TO 40KTS MONDAY AFTERNOON INTO
TUESDAY MORNING OVER MUCH OF LAKE SUPERIOR. WILL ISSUE A GALE
WATCH TO ACCOUNT FOR THE EXPECTED GALES...SPREADING FROM WEST TO
EAST MONDAY AFTERNOON/EVENING. WINDS WILL GRADUALLY DECREASE TUESDAY
AFTERNOON INTO TUESDAY NIGHT AS A WEAK HIGH PRESSURE RIDGE MOVES
ACROSS THE AREA. ANOTHER TROUGH WILL SWEEP SOUTHEAST ACROSS THE
UPPER GREAT LAKES REGION WEDNESDAY MORNING AND BRING AN INCREASE IN
WINDS OUT OF THE NORTHWEST (UP TO 30KTS) WHICH WILL CONTINUE INTO
THURSDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW WATCH FROM MONDAY MORNING THROUGH TUESDAY
MORNING FOR MIZ001>003-009.
LAKE SUPERIOR...
GALE WATCH FROM LATE MONDAY NIGHT THROUGH TUESDAY AFTERNOON FOR
LSZ267.
GALE WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY AFTERNOON FOR
LSZ265-266.
GALE WATCH FROM MONDAY AFTERNOON THROUGH LATE MONDAY NIGHT FOR
LSZ162.
GALE WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY MORNING FOR
LSZ263-264.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...SRF
AVIATION...ROLFSON
MARINE...SRF
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1106 PM CST SAT NOV 15 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 351 PM CST SAT NOV 15 2014
STEADY LIGHT SNOW HAS ENGULFED SOUTHERN MN IN LIGHT SNOW THROUGH THE
DAY...WITH THE HEAVIEST BAND SETTING UP ALONG THE IOWA BORDER AS
EXPECTED. FOR THE REMAINDER OF THE AFTERNOON...WE`RE EXPECTING MOST
OF THE SNOW IN SOUTHERN MN TO WEAKEN AS FORCING WANES...AND THE
F-GEN MAX SLIDES SOUTH INTO IOWA...AS FRONTOLYSIS TAKES OVER ACROSS
WEST CENTRAL THROUGH SOUTHERN MN. THIS TREND IS QUITE APPARENT ON
RADAR AND HAS BEEN HANDLED WELL BY THE HRRR FOR THE LAST SEVERAL
RUNS. SO...EXPECT A LULL FOR MUCH OF THE AFTERNOON AND THE EVENING.
ANOTHER DECENT SNOW BAND WILL DEVELOP LATER TONIGHT. IT WILL CROSS
THE MN/SD BORDER AROUND 6-7 PM AND CONTINUE EASTWARD...PRODUCING
LIGHT ACCUMULATIONS ACROSS THE SOUTHERN HALF OF THE STATE AND
THROUGH WEST CENTRAL WI. FOR THE TWIN CITIES...THIS BAND WILL
PRODUCE AN ADDITIONAL 0.5"-1" MAINLY FROM 9PM THROUGH 1AM.
CURRENTLY EXPECTING THE BACK EDGE OF THIS BAND TO CROSS THE MN/WI
LINE AT ABOUT 3AM...WITH LIGHT SNOW LINGERING UNTIL 5-6AM NEAR EAU
CLAIRE.
OVERNIGHT TEMPERATURES LAST NIGHT WERE A GOOD FIVE DEGREES COLDER
THAN EXPECTED OVER THE SOLID SNOW PACK. IN COLLABORATION WITH OTHER
OFFICES...WENT SLIGHTLY COOLER ACROSS THE WEST THAN MOST OF THE
GUIDANCE...BUT THE EASTERN CWA WILL RETAIN SOMEWHAT WARMER
TEMPERATURES UNDER CONSISTENT CLOUD COVER /AND LINGERING LIGHT
PRECIP OVERNIGHT/. BY TOMORROW MORNING...WINDS WILL HAVE TURNED
WESTERLY AND WILL INCREASE THROUGH THE DAY. STRONG CAA APPARENT AT
925H ON THE BACKSIDE OF THE WAVE WILL MAKE FOR A COLD SUNDAY. 925H
TEMPS AROUND -12C ACROSS MOST OF THE REGION WILL ONLY ALLOW SURFACE
TEMPS TO MIX INTO THE UPPER TEENS.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 351 PM CST SAT NOV 15 2014
THE WEEK AHEAD REMAINS EXTREMELY COLD FOR MID NOVEMBER WITH THREE
SURGES OF ARCTIC AIR FORECAST ACROSS THE UPPER MISSISSIPPI VALLEY.
THE FIRST IS SUNDAY NIGHT/MONDAY...THE SECOND TUESDAY NIGHT/WEDNESDAY
WITH THE THIRD ON THURSDAY. LOWS/HIGHS THROUGH THE PERIOD WILL
CONTINUE TO AVERAGE SOME 20 TO 30 DEGREES BELOW NORMAL. THE TREND
TODAY WAS TO CONTINUE LOWERING TEMPERATURES OVER THE BLENDED
GUIDANCE DUE TO A MORE EXPANSIVE SNOW PACK. THE ARCTIC SURGE THAT
OCCURS SUNDAY NIGHT/MONDAY OFFERS THE BEST CHANCE FOR SNOW
SHOWERS...ESPECIALLY ACROSS CENTRAL MINNESOTA AND WEST CENTRAL
WISCONSIN...WHERE A FLUFFY INCH OR TWO COULD OCCUR. THE OTHER TWO
ARCTIC SURGES HAVE THE BETTER MOISTURE AND FORCING TO THE NORTHEAST
OF OUR FORECAST AREA RESULTING IN LESS CHANCES FOR SNOW FOR US.
THE MAIN CONCERN IN THE LONG TERM IS THE BLOWING SNOW POTENTIAL IN
THE MINNESOTA RIVER VALLEY SUNDAY NIGHT AND MONDAY. THE CONCERN
FOR BLIZZARD CONDITIONS DEVELOPING ON MONDAY HAS WANED A BIT TODAY
AS ALL OF THE DETERMINISTIC MODELS HAVE DECREASED THE SURFACE
PRESSURE GRADIENT ACROSS THE MN FORECAST AREA FROM 10 MB TO 8 MB IN
THE PAST 24 HOURS. THIS HAS LOWERED WIND SPEED FORECASTS A LITTLE
ON MONDAY FROM KRWF TO KFRM. IN ADDITION...SNOWFALL ACCUMULATION
SO FAR TODAY HAS BEEN HIGHEST IN EASTERN SOUTH DAKOTA AND FAR
SOUTHWEST MINNESOTA (OUTSIDE OF OUR FORECAST AREA) WHERE 3 TO 5
INCHES HAVE BEEN COMMON. SNOWFALL IN OUR AREA OF WEST CENTRAL
THROUGH SOUTH CENTRAL MINNESOTA HAS BEEN MORE IN THE 1 TO 3 INCH
RANGE.
BUFKIT PROFILES FROM BOTH THE NAM AND GFS SHOW THAT THE BEST LOW
LEVEL LAPSE RATES AND HIGHEST TOP OF THE CHANNEL MOMENTUM TRANSFER
DON/T OCCUR UNTIL LATE MONDAY MORNING AND AFTERNOON FROM WEST
CENTRAL THROUGH SOUTH CENTRAL MINNESOTA. ALTHOUGH AREAS OF
BLOWING SNOW WILL BEGIN ACROSS WEST CENTRAL THROUGH SOUTH CENTRAL
MINNESOTA SUNDAY NIGHT IN THE WAKE OF THE ARCTIC FRONT...THERE
ARE STILL SOME INDICATIONS THAT SUSTAINED WIND SPEEDS COULD REACH
25 MPH FROM KRWF TO KFRM MONDAY AFTERNOON WITH GUSTS HITTING 40
MPH. THIS COULD RESULT IN NEAR BLIZZARD CONDITIONS FOR A COUPLE OF
HOURS IN THESE AREAS. COMPLICATING MATTERS IS THE THREAT FOR SNOW
SHOWERS ALONG WITH THE SATURATED LOW LEVEL CONDITIONS REMAINING IN
THE DENDRITIC GROWTH ZONE.
AT THIS POINT...DIDN/T HAVE ENOUGH CONFIDENCE TO ISSUE A BLIZZARD
WATCH FOR MONDAY FROM YELLOW MEDICINE AND RENVILLE COUNTIES ON
SOUTHEAST TO MARTIN AND FARIBAULT WITH THE PRESSURE GRADIENT
WEAKENING SOME AND THE HIGHER SNOW TOTALS TODAY TO OUR WEST. THERE
IS STILL PLENTY OF TIME LATER TONIGHT TO ISSUE A WATCH IF WIND
CONDITIONS CHANGE WITH THE 00Z MODEL RUNS. OTHERWISE...A WINTER
WEATHER ADVISORY FOR BLOWING SNOW WILL LIKELY BE ISSUED ON SUNDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1101 PM CST SAT NOV 15 2014
LIGHT SNOW IS TRENDING A BIT SLOWER THAN ANTICIPATED AND WILL
CONTINUE ACROSS MN/WI TONIGHT AND SLOWLY COME TO AN END FROM WEST
T0 EAST BETWEEN 05Z-08Z IN MN...AND 08Z-12Z IN WI. HIGH
CONFIDENCE IN MVFR/IFR VISIBILITY AND MVFR CEILINGS UNTIL THE SNOW
MOVES OUT.
KMSP...
LIGHT SNOW CONTINUES TONIGHT BUT SHOULD BE WELL TO THE EAST
BEFORE THE MORNING COMMUTE BEGINS.
/OUTLOOK FOR KMSP/
MON...SLIGHT CHC -SN WITH IFR/MVFR CIGS. WINDS NW 15-20 G 25 KTS.
TUE...VFR. WINDS W 10-15 KTS.
WED...VFR. WINDS NW 10-15 KTS G 20 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR
MNZ073>076-082>085-091>093.
WI...NONE.
&&
$$
SHORT TERM...SPD
LONG TERM...RAH
AVIATION...CLF
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
346 AM CST Sun Nov 16 2014
.SHORT TERM...(Today through Tuesday)
Issued at 345 AM CST SUN NOV 16 2014
Record breaking cold likely early this week...
Regional radars showing plenty of lgt snow across the region this
morning as main upper-level trough and associated cold front
continue to slide through the area. So far snowfall reports through
the overnight have been far and few between....however accumulations
of less than a half inch are likely through the remainder of the
early morning hrs. Fcst becomes a bit more interesting after 12z as
models have trended a tad further north with frontal band QPF axis
that is expected to impact the far southern zones later this morning
into early afternoon. That said...forcing for ascent looks to be
fairly decent as main upper PV lobe slides east through the course of
the day today. Additionally...models show increasing frontogenesis in
the 850-700 hPa layer as the thermal gradient increases thanks to
increasing cold air advection behind aforementioned secondary cold
front. All told...chances look fairly promising for some light
accumulations south of the KC Metro later today.
Initial look earlier this evening suggested we may need another
advisory for far southern zones to account for anticipated snowfall.
After collaboration with both SGF and LSX...have elected to hold off
on issuing any flags as snowfall accumulations will likely barely
eclipse the 1" mark. This decision is also supported by the recently
arriving 6z NAM and latest runs of the HRRR which are now trending a
bit further south than the earlier runs. In any event...can/t rule
out some minor travel problems later today and daytime shift can
issue SPS statements as needed. Further north...except for some
occasional flurries and chilly conditions as highs top out in the
middle to upper 20s.
Beyond this...story quickly turns to bitterly cold temps as the
chilliest airmass of the season descends upon the region following the
passage of another cold front (albeit dry) overnight tonight.
Following its passage...models show the -20C 850 isotherm making its
way south into northern sections of the fcst area during the day on
Monday. This should result in high temps struggling to reach 20
degrees across much of the area which combined with brisk northwest
winds...will result in single digit windchills through the day.
Confidence continues to increase that record cold high temps likely
to be reached on Monday with record lows also likely Tuesday morning
as the mercury easily falls into the single digits (see climate
section below).
Finally by Tuesday...high pressure across the far southern Plains
will begin tracking east which combined with low pressure entering
the northern Plains...should allow low-level winds to change over to
the south. The end result will be daytime highs climbing back into
the upper 20s to lower 30s Tuesday afternoon with the moderation
trend expected to continue through midweek.
.LONG TERM...(Wednesday through Saturday)
Issued at 345 AM CST SUN NOV 16 2014
The extended continues to look cold and dry for the first half of
the extended before precipitation chances increase towards the end
the work week. Models start out in good agreement at the beginning
of the period on Wednesday with the upper level pattern revealing
upper level troughing over the Great Lakes and Ohio River Valley and
upper level ridging over the western CONUS. Northwest flow aloft
will still be in place over the area however, it will relax a bit
from the very cold temperatures that will affect the area on Monday
and Tuesday. Expect highs in the lower 30s to lower 40s. The model
solutions begin to diverge during this time period with the GFS
keeping the area under northwest flow again Thursday before the
pattern becomes more zonal Thursday through Saturday. The EC depicts
a reinforcing upper trough digging through the Midwest Thursday into
Friday which would reinforce the cold pattern in place. The Canadian
is a middle of the road solution. Have maintain a blended solution
to account for models differences.
The models do come into some agreement with the main feature of
interest in the extended in the form of an upper level trough. This
trough will move from the southwestern Conus into the western High
Plains on Saturday. Warm air advection showers will be underway on
Saturday ahead of the system. The main question is how this system
will evolve. The GFS is progressive with this system in moving a
open wave through the area Saturday night into Sunday. The EC digs
and slows the trough as it moves into the Plains Saturday and Sunday
and closes a low in the base of the trough across Oklahoma on
Sunday. this would provide for a colder and prolonged wet solution.
As such, have chance POPs with rain or snow wording in the forecast
for Saturday night and Sunday to account for difference in
solutions.
&&
.AVIATION...(For the 06Z TAFS through 06Z Sunday Night)
Issued at 1055 PM CST SAT NOV 15 2014
MVFR cigs and very light snow over the terminals will prevail through
most of the night. Latest obs upstream show surface winds to shift
from light south to northwest and pick up behind a surface front. Now
seeing gusts in southeast Nebraska but the gradient will be weaker
over the terminals here...but will have to watch for a few gusts late
morning. Some VFR OVC050 clouds will help keep the stronger winds
from mixing down as well. The cigs should clear by around mid day or
so and winds will diminish late in the period.
&&
.CLIMATE...
Updated at 345 AM CST SUN NOV 16 2014
Monday
November 17th Current Record Low Forecast High Monday
Record Low Highs High Afternoon
--------------------------------------------------------------------
Kansas City 24 in 1891 21
St. Joseph 26 in 1951 21
Tuesday
November 18th Current Record Low Forecast Low Tuesday
Record Lows Morning
--------------------------------------------------------------------
Kansas City 14 in 1903 7
St. Joseph 16 in 1989 5
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
MO...NONE.
&&
$$
SHORT TERM...32
LONG TERM...73
AVIATION...Adolphson
CLIMATE...Cutter
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1138 PM CST Sat Nov 15 2014
.UPDATE:
Issued at 1028 PM CST Sat Nov 15 2014
Small bands of snow are finally moving out of the area after producing
generally 1/2 inch or less of snowfall over the area. Weak
shortwave trough is now moving east of the Mississippi river which
will allow weak subsidence to move in for the rest of the night.
Still expect mainly cloudy skies with temperatures falling close
to predicted lows.
Britt
&&
.SHORT TERM: (Through Late Tonight)
Issued at 347 PM CST Sat Nov 15 2014
Shortwave exiting the eastern Plains into the Mississippi Valley is
producing a little bit of light snow and flurry activity across the
CWFA today. Looks like the best snowfall has moved north of our
CWFA across extreme northeast Missouri and southeast Iowa into west
central Illinois. The broad scale mid level lift associated with
the shortwave is lifting quickly northeast according to the RAP and
NAM. Will likely see a little bit of lingering snowfall up there
this evening, but any accumulations this evening should be well
under an inch.
Further south, HRRR and RAP have been very insistent that there will
be a frontogenetical band of snow this evening somewhere between
I-44 and I-70. The band will move northeast affecting parts of the
STL metro area with some light snow. Simulated reflectivity off the
4km NCEP and NSSL WRF models also show this, and the operational NAM
and GFS bear this out with a few hundredths of QPF. Latest radar
mosaic shows a band of snow developing west central Missouri
now...so this looks likely to happen. Have a band of likely PoPs
this evening in to account for this snow, stretching across central
Missouri into southwest Illinois to account for this.
Carney
.LONG TERM: (Sunday through Next Saturday)
Issued at 347 PM CST Sat Nov 15 2014
(Sunday thru Tuesday)
This period will continue to feature much below normal temps and
another shot at accumulating snow. Models have come into better
agreement with the system for Sunday/Sunday night. All guidance has
shifted the forcing and subsequently the precip shield further
north. Timing should be similar to today`s event. Precip is
expected to begin across cntrl and SE MO around noon and then spread
east thru the rest of the CWA during the aftn and then clear from W
to E during the evng and be but a memory by midnight. The main
p-type should be snow with temps aloft plenty cold enough to support
ice crystal formation but...air temps above freezing at the
beginning of the event may cause a rain/snow mix at the onset of the
precip. I think the mix won`t last long as temps should wet bulb
shortly after the precip begins. This will likely lead to a
non-diurnal temp trend as temps fall across the sthrn CWA as the
precip progresses east. Accum rates may be limited early on in the
event for a variety of reasons beyond the warm air temps
including...ground temps will likely be above freezing, snowfall
rates may not be high enough and the aftn sun...even with the
diminished angle...will have an effect. Event total snowfall amounts
should be 1-2 inches along and south of I70. There may be a band of
slightly enhanced snowfall along the I44 corridor that may reach
upwards of 3 inches but not confident on band placement to include
in the fcst attm. The system quickly lifts east after midnight.
Monday looks like a raw day with potentially steady or slowly
falling temps and a stiff NW wind as a 1030mb sfc high builds in.
850 temps fall from the negative single digits at 6Z Monday to the
negative mid teens to near -20 by Monday evening. There is also an
impressive short wave dropping down in the NW flow on Monday that
should instigate at least occnl flurries with the possibility of
actual snow showers...as was the case this past Thursday. Models
hint at patchy QPF which would equate to a few tenths of an inch of
snow...but will let later shifts asses that threat as it is still 2
days away. Tuesday should be the last truly cold day as the sfc
ridge passes to the south.
(Tuesday night thru Friday)
The upper flow flattens thru the end of the week which will allow
for a moderating trend. Winds will swing around to the south on the
backside of the high Tuesday night. 850 temps near 0 and a Srly wind
will boost temps to the upper 30s north to the upper 40s south
on Wednesday. The next short waves pushes a cold front thru late in
the day on Wednesday causing temps on Thursday and Friday to be a
touch cooler. This front appears to be dry at this time. Models
guidance diverges after this feature with the GFS building a strong
sfc ridge into the Midwest for the end of the week while the ECMWF
has another short wave and an attendant weak sfc low that tracks
across sthrn MO/IL Thursday/Thursday night.
Both models suggest another storm system for either the wknd and/or
early next week as the next main short wave approaches in the mean
flow.
2%
&&
.AVIATION: (For the 06z TAFs through 06z Sunday Night)
Issued at 1131 PM CST Sat Nov 15 2014
The shortwave has moved east of the taf sites with the light
snow/flurries coming to an end. Vfr conditions to persist until
next weather system moves in by mid morning. Light and variable
winds to pickup from the west with cigs/vsbys lowering to mvfr as
next chance for snow moves in. Will see just flurries at KUIN by
14z, while rest of taf sites to see light to moderate snow between
15z and 22z. Activity to exit by 00z-01z Monday timeframe with
cigs/vsbys lifting back to vfr.
Specifics for KSTL:
The shortwave has moved east of the metro area with the light
snow/flurries coming to an end. Vfr conditions to persist until
next weather system moves in by 17z Sunday. Light and variable
winds to pickup from the west with cigs/vsbys lowering to mvfr as
next chance for snow moves in. Light to moderate snow will move
in by 17z Sunday and persist til around 22z Sunday. Activity to exit
by 01z Monday timeframe with cigs/vsbys lifting back to vfr.
Byrd
&&
.CLIMATE:
Issued at 748 PM CST Thu Nov 13 2014
The following are record low maximums and record low minimums for
each of the next 4 days, which corresponds to the expected length
of the current cold spell and record snowfall for St. Louis and
Columbia for Saturday and Sunday when the area is expecting the
first widespread accumulating snowfall of the season.
Date: 11/15 11/16 11/17 11/18
St. Louis
Low High: 29/1940 29/1997 17/1880 25/1880
Low: 11/1940 13/1959 6/1959 14/1932
Snowfall: 0.1/1997 1.0/1951
Columbia
Low High: 28/1940 30/1932 23/1959 27/1903
Low: 6/1940 8/1959 4/1959 8/1891
Snowfall: 4.8/1932 0.1/1989
Quincy
Low High: 29/1940 28/1997 19/1959 24/1903
Low: 7/1940 4/1959 3/1959 7/1903
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1055 PM CST Sat Nov 15 2014
.DISCUSSION...
Issued at 418 PM CST SAT NOV 15 2014
Tonight - Sunday:
As today`s system which generated 2-4 inches of snow over the far
northern counties exits the region our attention turns to three
secondary areas of snow. An area of snow over Nebraska is tied to a
shortwave trough moving east through western SD/NE. The trailing
band of enhanced clouds/snow is expected to drag through the CWA
overnight but only the far northwestern counties have a chance of
more than a dusting...maybe 1/2" to and inch. The expected band of
snow should diminish in intensity overnight but most areas will see
at least intermittent flurries.
The second region of snow is a result of the seeder-feeder mechanism
as noted by the broken area of enhanced mid clouds which have formed
from east central KS into west central MO. There likely is a weak
mid-level vorticity max tied to this region of cloud and the NAM h7
prog seems to hint on this. Only the short-range HRRR has picked up
on this. Could get a quick half inch of snow across the far southern
CWA during the late afternoon/early evening hours before the feature
weakens as it quickly heads east.
The third area of snow is expected to form over the CO Rockies
tonight and rapidly expand as a narrow band in response to the left
front quad of an upper level jet streak races through the Central
Rockies and into KS/OK Sunday morning. Operational models do depict
one or two vorticity lobes tracking into the region within an
overall area of ascent. At this time the northern edge of the
expected snow band could skirt across our far southern counties so
have added chance PoPs to this area.
Otherwise, until the primary upper trough passes through late on
Sunday am expecting mostly cloudy skies for most of the CWA. This
will mute the diurnal temperature range.
Monday - Tuesday:
Much below average temperatures will continue during this period
with the potential for a record low max temperature on Monday and
record setting lows Tuesday morning. Another upper trough will dig
southward Sunday night and Monday and result in falling mid/upper
level heights and enhance the flow of Arctic air southward from the
Canadian Plains to central U.S. Another surge of this air will move
in during this period. Steep lapse rates below 750mb and a moist
layer residing within the boundary layer suggests a good chance for
instability snow showers or flurries Monday afternoon.
Wednesday - Saturday:
This should be a dry period with a continuation of the unseasonably
cold regime. Cyclonic/northwest flow aloft will continue featuring
the potential for weak embedded shortwaves to pass through. However,
the airmass will be quite dry so it should remain dry. A slight
moderation in temperatures are expected but they will remain about
15 degrees below average.
A particularly cold air mass will swing into the Central Plains
Monday into Tuesday. This will result in the coldest temperatures we
have seen this fall with both Monday`s high temperatures and Tuesday
morning`s low temperatures possibly setting new records. Here is a
quick look at just some of those threatened temperature records.
&&
.CLIMATE...
Issued at 418 PM CST SAT NOV 15 2014
Monday
November 17th Current Record Low Forecast High Monday
Record Low Highs High Afternoon
--------------------------------------------------------------------
Kansas City 24 in 1891 22
St. Joseph 26 in 1951 22
Tuesday
November 18th Current Record Low Forecast Low Tuesday
Record Lows Morning
--------------------------------------------------------------------
Kansas City 14 in 1903 7
St. Joseph 16 in 1989 5
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
MO...WINTER WEATHER ADVISORY until Midnight CST tonight FOR
MOZ001>003-011.
&&
.AVIATION...(For the 06Z TAFS through 06Z Sunday Night)
Issued at 1055 PM CST SAT NOV 15 2014
MVFR cigs and very light snow over the terminals will prevail through
most of the night. Latest obs upstream show surface winds to shift
from light south to northwest and pick up behind a surface front. Now
seeing gusts in southeast Nebraska but the gradient will be weaker
over the terminals here...but will have to watch for a few gusts late
morning. Some VFR OVC050 clouds will help keep the stronger winds
from mixing down as well. The cigs should clear by around mid day or
so and winds will diminish late in the period.
$$
DISCUSSION...MJ
AVIATION...Adolphson
CLIMATE...Cutter
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
1030 PM CST Sat Nov 15 2014
.UPDATE:
Issued at 1028 PM CST Sat Nov 15 2014
Small bands of snow are finally moving out of the area after producing
generally 1/2 inch or less of snowfall over the area. Weak
shortwave trough is now moving east of the Mississippi river which
will allow weak subsidence to move in for the rest of the night.
Still expect mainly cloudy skies with temperatures falling close
to predicted lows.
Britt
&&
.SHORT TERM: (Through Late Tonight)
Issued at 347 PM CST Sat Nov 15 2014
Shortwave exiting the eastern Plains into the Mississippi Valley is
producing a little bit of light snow and flurry activity across the
CWFA today. Looks like the best snowfall has moved north of our
CWFA across extreme northeast Missouri and southeast Iowa into west
central Illinois. The broad scale mid level lift associated with
the shortwave is lifting quickly northeast according to the RAP and
NAM. Will likely see a little bit of lingering snowfall up there
this evening, but any accumulations this evening should be well
under an inch.
Further south, HRRR and RAP have been very insistent that there will
be a frontogenetical band of snow this evening somewhere between
I-44 and I-70. The band will move northeast affecting parts of the
STL metro area with some light snow. Simulated reflectivity off the
4km NCEP and NSSL WRF models also show this, and the operational NAM
and GFS bear this out with a few hundredths of QPF. Latest radar
mosaic shows a band of snow developing west central Missouri
now...so this looks likely to happen. Have a band of likely PoPs
this evening in to account for this snow, stretching across central
Missouri into southwest Illinois to account for this.
Carney
.LONG TERM: (Sunday through Next Saturday)
Issued at 347 PM CST Sat Nov 15 2014
(Sunday thru Tuesday)
This period will continue to feature much below normal temps and
another shot at accumulating snow. Models have come into better
agreement with the system for Sunday/Sunday night. All guidance has
shifted the forcing and subsequently the precip shield further
north. Timing should be similar to today`s event. Precip is
expected to begin across cntrl and SE MO around noon and then spread
east thru the rest of the CWA during the aftn and then clear from W
to E during the evng and be but a memory by midnight. The main
p-type should be snow with temps aloft plenty cold enough to support
ice crystal formation but...air temps above freezing at the
beginning of the event may cause a rain/snow mix at the onset of the
precip. I think the mix won`t last long as temps should wet bulb
shortly after the precip begins. This will likely lead to a
non-diurnal temp trend as temps fall across the sthrn CWA as the
precip progresses east. Accum rates may be limited early on in the
event for a variety of reasons beyond the warm air temps
including...ground temps will likely be above freezing, snowfall
rates may not be high enough and the aftn sun...even with the
diminished angle...will have an effect. Event total snowfall amounts
should be 1-2 inches along and south of I70. There may be a band of
slightly enhanced snowfall along the I44 corridor that may reach
upwards of 3 inches but not confident on band placement to include
in the fcst attm. The system quickly lifts east after midnight.
Monday looks like a raw day with potentially steady or slowly
falling temps and a stiff NW wind as a 1030mb sfc high builds in.
850 temps fall from the negative single digits at 6Z Monday to the
negative mid teens to near -20 by Monday evening. There is also an
impressive short wave dropping down in the NW flow on Monday that
should instigate at least occnl flurries with the possibility of
actual snow showers...as was the case this past Thursday. Models
hint at patchy QPF which would equate to a few tenths of an inch of
snow...but will let later shifts asses that threat as it is still 2
days away. Tuesday should be the last truly cold day as the sfc
ridge passes to the south.
(Tuesday night thru Friday)
The upper flow flattens thru the end of the week which will allow
for a moderating trend. Winds will swing around to the south on the
backside of the high Tuesday night. 850 temps near 0 and a Srly wind
will boost temps to the upper 30s north to the upper 40s south
on Wednesday. The next short waves pushes a cold front thru late in
the day on Wednesday causing temps on Thursday and Friday to be a
touch cooler. This front appears to be dry at this time. Models
guidance diverges after this feature with the GFS building a strong
sfc ridge into the Midwest for the end of the week while the ECMWF
has another short wave and an attendant weak sfc low that tracks
across sthrn MO/IL Thursday/Thursday night.
Both models suggest another storm system for either the wknd and/or
early next week as the next main short wave approaches in the mean
flow.
2%
&&
.AVIATION: (For the 00z TAFs through 00z Sunday Evening)
Issued at 611 PM CST Sat Nov 15 2014
Initial shortwave exiting region, however secondary shortwave over
west central MO tracking to the east northeast, so will continue
to see light snow/flurries for taf sites along I-70 corridor this
evening. So have mvfr cigs through 02z Sunday for KCOU and through
03z Sunday for metro area tafs. Another stronger shortwave to
slide through region late Sunday morning through early Sunday
evening with mvfr conditions once again for taf sites along I-70
corridor with heaviest snow just south of these sites. Southeast
to south winds to become light and variable overnight, then veer
to the west as stronger shortwave moves through on Sunday.
Specifics for KSTL:
Initial shortwave exiting region, however secondary shortwave over
west central MO tracking to the east northeast, so will continue
to see light snow/flurries for metro area this evening. So have mvfr
cigs through 03z Sunday KSTL. Another stronger shortwave to slide
through region late Sunday morning through early Sunday evening
with mvfr conditions once again for metro area with heaviest snow
just south of metro area. Southeast to south winds to become
light and variable by 03z Sunday, then veer to the west as stronger
shortwave moves through around 17z Sunday. Snow to taper off after
00z Monday with cigs lifting to vfr.
Byrd
&&
.CLIMATE:
Issued at 748 PM CST Thu Nov 13 2014
The following are record low maximums and record low minimums for
each of the next 5 days, which corresponds to the expected length
of the current cold spell and record snowfall for St. Louis and
Columbia for Saturday and Sunday when the area is expecting the
first widespread accumulating snowfall of the season.
Date: 11/15 11/16 11/17 11/18
St. Louis
Low High: 29/1940 29/1997 17/1880 25/1880
Low: 11/1940 13/1959 6/1959 14/1932
Snowfall: 0.1/1997 1.0/1951
Columbia
Low High: 28/1940 30/1932 23/1959 27/1903
Low: 6/1940 8/1959 4/1959 8/1891
Snowfall: 4.8/1932 0.1/1989
Quincy
Low High: 29/1940 28/1997 19/1959 24/1903
Low: 7/1940 4/1959 3/1959 7/1903
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1133 PM CST SAT NOV 15 2014
.UPDATE...
ISSUED AT 904 PM CST SAT NOV 15 2014
THE FRONT CONTS TO MAKE STEADY PROGRESS TO THE SOUTHEAST THROUGH
THE CWA THIS EVNG. AREAS OF MAINLY LIGHT SNOW HAVE CONTD ALONG AND
AHEAD OF THE COLD FRONT...AND THIS IS EXPECTED TO CONT TO TRACK
TO THE EAST THROUGH THE REST OF THE EVNG AS THE COLD FRONT MOVS E
AND THE UPPER LEVEL FORCING EXITS. SFC 3-HR PRES RISES OF 2-3 MB
ARE DIRECTLY BEHIND THE FRONT AND ARE ALLOWING FOR GUSTY NORTHWEST
WINDS. THIS MAY ALLOW FOR SOME PATCHY BLOWING SNOW IN OPEN
AREAS...BUT UPSTREAM OBSERVATIONS INDICATE LITTLE IN THE WAY OF
VISIBILITY RESTRICTIONS. THUS HAVE CANCELLED THE WNTR WX ADVRY FOR
THE NW CWA AND AS THE LAST OF THE SN EXITS THE CNTRL/ERN CWA WE
WILL DO THE SAME THERE BUT KEEP SOME MENTION OF PATCHY BLOWING
SNOW GOING. OTHERWISE OTHER THAN SOME MINOR TIMING CHANGES
ONGOING FORECAST WAS IN GOOD SHAPE WITH NO SIGNIFICANT CHANGES
PLANNED.
&&
.SHORT TERM...(TONIGHT THROUGH TUESDAY)
ISSUED AT 331 PM CST SAT NOV 15 2014
ENDING SNOW TONIGHT...THEN COLD TEMPERATURES THE NEXT FEW DAYS...ARE
THE PRIMARY FORECAST CONCERNS.
FIRST ROUND OF SNOW TIED TO SOUTHERN SHORTWAVE/WARM ADVECTION
PATTERN MOVED EAST/NORTHEAST OF THE CWA BY EARLY AFTERNOON. THIS
AREA DROPPED AN INCH OR TWO OF SNOW ACROSS THE SOUTHERN HALF OF
THE CWA. ANOTHER AREA OF SNOW WAS ENTERED THE WESTERN PART OF
NORTHEAST NEBRASKA EARLY IN THE AFTERNOON. THIS WAS TIED TO
STRONGER UPPER LOW/TROUGH SWINGING THROUGH WESTERN SOUTH DAKOTA.
75KT MID LEVEL JET WAS ROUNDING BASE OF THIS FEATURE...INCREASING
LIFT IN NORTHEAST WHERE SECOND ROUND OF SNOW WAS FALLING THIS
AFTERNOON. CHARACTER OF RADAR RETURNS SUGGEST THIS AREA WILL
PRODUCE LIGHT SNOW FOR THE MOST PART...WITH A FEW ROUNDS OF
MODERATE SNOW FROM TIME TO TIME. PROGRESSIVE NATURE ALSO SUGGESTS
MESOSCALE MODEL FORECASTS FROM HRRR AND RAP IN SHOWING SNOW
AFFECTING MAINLY THE NORTHERN HALF OF THE CWA AND WINDING DOWN BY
MIDNIGHT STILL LOOKS GOOD. ADDITIONAL AMOUNTS OF 1 TO 2 INCHES ARE
POSSIBLE IN THE NORTHERN TWO-THIRDS OF THE CWA TAPERING TO LESS
THAN AN INCH TOWARD THE KANSAS BORDER.
BACK EDGE OF SNOW WILL ALSO COINCIDE WITH COLD FRONT SWEEPING ACROSS
THE PLAINS. FRONT WILL PASS NORFOLK BY 9 PM AND BE APPROACHING OMAHA
BY MIDNIGHT. GUSTY NORTHWEST WINDS OF 15 TO 25 MPH SHOULD
FOLLOW...CAUSING A LITTLE BLOWING AND DRIFTING OF SNOW OVERNIGHT
BEFORE WINDS BEGIN TO SUBSIDE SOME ON SUNDAY. CLEARING SKIES AFTER
MIDNIGHT...COLD AIRMASS AND FRESH SNOW COVER WILL LEAD TO COLD
TEMPERATURES BY MORNING...WITH WINDS ONLY THING KEEPING LOWS FROM
BOTTOMING OUT. SINGLE DIGITS ARE FORECAST MOST EVERYWHERE.
SUNDAY WILL BRING SUNSHINE AND SOUTHWEST FLOW AHEAD OF A REINFORCING
COLD FRONT SLATED TO ARRIVE INTO NORTHEAST NEBRASKA IN THE
AFTERNOON...THEN THROUGH THE REST OF THE AREA DURING THE EVENING.
SNOW COVER WILL KEEP TEMPS FROM REACHING MAXIMUM POTENTIAL SUNDAY
AFTERNOON...WITH LOWER 20S EXPECTED MOST AREAS. MORE GUSTY NORTHWEST
WINDS WILL ACCOMPANY COLD FRONT AND SHOULD CONTINUE ALL NIGHT.
EXTREMELY COLD AIRMASS FOLLOWS THE FRONT WITH MODELS SHOWING -20
850 TEMPERATURES INTO OUR NORTHERN CWA BY 12Z MONDAY. THIS WILL
TRANSLATE TO LOWS AGAIN IN THE SINGLE DIGITS WITH HIGHS REBOUNDING
ONLY BACK INTO THE TEENS MONDAY AFTERNOON. WIND CHILLS MONDAY
MORNING WILL LIKELY FALL TO 15 BELOW OR COLDER FOR MUCH OF THE
NORTHERN HALF OF THE CWA.
DECREASING WINDS AND CLEARING SKIES SUGGEST TUESDAY MORNING MAY BE
THE COLDEST OF THIS RECENT COLD SPELL. LOWS NEAR ZERO ARE LIKELY
ACROSS ALL OF EASTERN NEBRASKA AND SOUTHWEST IOWA...WITH SUB-ZERO
TEMPS NEARLY A CERTAINTY IN OUR NORTH. SOUTHWEST FLOW RETURNS FOR
TUESDAY...HELPING TO WARM TEMPS BACK INTO THE MID 20S IN THE
AFTERNOON.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 331 PM CST SAT NOV 15 2014
SLOWLY MODERATING TEMPERATURES APPEAR TO BE THE MAIN STORY IN THE
LONGER TERM PERIOD.
ANOTHER SHORTWAVE IS SHOWN BY GFS/ECMWF SLAMMING THROUGH MINNESOTA
AND IOWA TUESDAY NIGHT...BRINGING ANOTHER SHOT OF COLDER AIR INTO
THE PLAINS THROUGH WEDNESDAY. HOWEVER THIS WILL NOT BE NEARLY AS
COLD AS EARLIER IN THE WEEK WITH HIGHS WEDNESDAY INTO THE 20S AND
LOWER 30S. MID LEVEL HEIGHTS BEGIN A SLOW RISE FOR THE REST OF THE
WEEK AS FLOW BECOMES MORE ZONAL BEHIND TUESDAY NIGHT SHORTWAVE.
ANOTHER SHOT OF SOMEWHAT COOLER AIR IS EXPECTED THURSDAY...BUT THAT
LOOKS SHORT-LIVED. HAVE HIGHS REBOUNDING BACK INTO THE 30S FRIDAY
AND SATURDAY. OTHERWISE A DRY FORECAST REMAINS INTACT.
&&
.AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1129 PM CST SAT NOV 15 2014
SNOW HAS GENERALLY SHIFTED OUT OF THE ALL TAF SITES THIS EVENING.
A FEW FLURRIES REMAIN POSSIBLE AT KOMA FOR AN HOUR OR SO...BUT NO
ADDITIONAL VISBY RESTRICTIONS ARE EXPECTED. MVFR CIGS HAVE CLEARED
KOFK/KLNK AND WILL CLEAR KOMA BY 08Z. SFC CDFNT IS THROUGH ALL 3
TAF SITES WITH NW WINDS AOA 12 KT WITH SOME GUSTS EXPECTED FOR A
FEW MORE HOURS. VFR CONDS ARE EXPECTED THROUGH THE DAY ON
SUN...BUT ANOTHER FRONT WILL MOVE TOWARD THE TAF SITES LATE SUN
AFTN/EARLY EVNG ALLOWING FOR WINDS TO INCREASE AGAIN FOR THE NW
AND A VFR SC DECK TO MV INTO ALL 3 SITES TO END THE PERIOD.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
UPDATE...BOUSTEAD
SHORT TERM...DERGAN
LONG TERM...DERGAN
AVIATION...BOUSTEAD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
341 AM CST SUN NOV 16 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 340 AM CST SUN NOV 16 2014
A WINTER WEATHER ADVISORY AND A WIND ADVISORY CONTINUE TO HEADLINE
THE SHORT TERM PERIOD. A STRONG COLD FRONT WILL PUSH ACROSS THE
NORTH BEGINNING AROUND 12Z AND MAKE ITS WAY TO THE SOUTHERN BORDER
BY 18Z. STRONG WINDS WILL FOLLOW THE FRONT WITH BLOWING/DRIFTING
SNOW IN THE WINTER WEATHER ADVISORY AREA. ONLY CHANGE TO THE ONGOING
WINTER WEATHER ADVISORY WAS TO ADD KIDDER COUNTY SINCE THEIR
SNOWFALL TOTAL LAST WEEKEND WAS COMPARABLE WITH BURLEIGH COUNTY.
GUSTY WINDS ARE SIMILAR IN BOTH LOCATIONS TODAY.
CURRENT WATER VAPOR IMAGERY SHOWS A POTENT SHORTWAVE WITH
SUBSIDENCE/DARKENING SIGNATURE PUSHING INTO SOUTHERN SASKATCHWEAN.
AT THE SURFACE...CURRENT ANALYSIS PLACES 3HR PRESSURE FALLS OF
6MB ACROSS NORTHWEST NORTH DAKOTA. THE COLD FRONT IS APPROXIMATELY
LOCATED FROM KALISPELL MONTANA TO SWIFT CURRENT SASKATCHEWAN...AND
NORTHEAST INTO LAKE WINNIPEG MANITOBA. THE MAXIMUM 3HR PRESSURE
BUBBLE OF 4 TO 5 MB IS LOCATED OVER SOUTHEAST ALBERTA. THE RAP13
HAS A GOOD HANDLE ON THE CURRENT FRONTAL LOCATION AND LOCATION/MAGNITUDE
OF CURRENT PRESSURE FALL/RISE COUPLET. EXPECT THE MAX PRESSURE
FALLS BETWEEN DICKINSON AND BISMARCK BY 12Z...WITH PRESSURE RISES
PUSHING INTO NORTHWEST NORTH DAKOTA BETWEEN 12Z-15Z SIGNIFYING THE
PASSAGE OF THE COLD FRONT. HENCE THE CURRENT TIMING OF THE
AFOREMENTIONED WINTER WEATHER ADVISORY AND WIND ADVISORY ALL LOOK
ON TRACK. OVERALL...AN AVERAGE RANGE OF SUSTAINED/MAX GUSTS PER
NAM/GFS/RAP BUFKIT SOUNDINGS AND THE 80M HRRR SHOWS NORTHWEST
WINDS SUSTAINED BETWEEN 25KT-35KT...AND GUSTS OF 35KT-45KT.
LOW CLOUDS ALONG WITH ISOLATED TO SCATTERED SNOW SHOWERS WILL ALSO
ACCOMPANY THE FRONTAL PASSAGE. ALTHOUGH THE STRONGEST WINDS WILL
EXIT BY EARLY EVENING...WINDS WILL REMAIN GUSTY THROUGH THE NIGHT
WITH LOW LEVEL ADIABATIC MIXING CONTINUING.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 340 AM CST SUN NOV 16 2014
A POTENTIAL MODERATION IN TEMPERATURES LATE THIS WEEK HIGHLIGHTS
THE EXTENDED FORECAST.
THE 00 UTC SUITE IS IN AGREEMENT ON THE ANOMALOUS HIGH AMPLITUDE
UPPER LEVEL PATTERN ACROSS NORTH AMERICA BREAKING DOWN TO A NEAR
ZONAL PATTERN BY NEXT WEEKEND IN A BROAD VERY LOW AMPLITUDE
TROUGH. THIS WOULD SIGNAL A RECOVERY FROM THE ARCTIC TEMPERATURES
TO STILL BELOW NORMAL...YET MORE TOLERABLE HIGHS NEAR FREEZING BY
NEXT WEEKEND. THE EXTENDED FORECAST LOOKS TO BE PRECIPITATION FREE
LACKING THE NEEDED MOISTURE RECOVERY FROM THE ARCTIC AIRMASS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 340 AM CST SUN NOV 16 2014
A STRONG COLD FRONT WILL SWEEP FROM NORTHERN BORDER AT 12Z SUNDAY TO
THE SOUTHERN BORDER BY 18Z SUNDAY. BEHIND THE FRONT EXPECT MVFR CIGS
TO DEVELOP AND REMAIN THROUGH THE DURATION OF THE TAF PERIOD. GUSTY
NORTHWEST WINDS OF 30 TO 45 MPH WILL ALSO DEVELOP BEHIND THE FRONT
WHICH WILL PRODUCE BLOWING/DRIFTING SNOW. EXPECT IFR VSBYS AT KDIK
AND MVFR VSBYS AT KBIS. OVER THE REMAINING TERMINALS...LIGHT SNOW
SHOWERS AND GUSTY WINDS WILL PRODUCE VSBYS AROUND 6SM AT TIMES.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 9 AM CST /8 AM MST/ THIS MORNING TO
6 AM CST /5 AM MST/ MONDAY FOR NDZ017>020-031>034-040>045.
WIND ADVISORY FROM 9 AM THIS MORNING TO 9 PM CST THIS EVENING
FOR NDZ001>003-009>011-021.
WIND ADVISORY FROM NOON TODAY TO 9 PM CST THIS EVENING FOR
NDZ004-005-012-013-022-023-025-037-048.
WINTER WEATHER ADVISORY FROM NOON TODAY TO 6 AM CST MONDAY FOR
NDZ035-036-046-047-050-051.
&&
$$
SHORT TERM...KS
LONG TERM...AYD
AVIATION...KS
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1144 PM EST SAT NOV 15 2014
.SYNOPSIS...
HIGH PRESSURE WILL SLIDE OFF THE EAST COAST TONIGHT WHILE A STORM
SYSTEM ORGANIZES TO OUR SOUTHWEST ON SUNDAY AND BRINGS RAINFALL
TO THE AREA INTO THE DAY MONDAY. ARCTIC AIR WILL FOLLOW THIS
SYSTEM MONDAY NIGHT INTO MIDWEEK WITH STRONG WINDS AND VERY COLD
TEMPERATURES.
&&
.NEAR TERM /THROUGH SUNDAY/...
AS OF 945 PM EST SATURDAY...
FORECAST PERIOD WILL FEATURE A RETREATING AREA OF SURFACE HIGH
PRESSURE TONIGHT AND ON SUNDAY WITH WARM AIR ADVECTION AND
SOUTHWESTERLY FLOW BRINGING MILDER TEMPS AND INCREASING CLOUDS.
MINOR ADJUSTMENT TO OVERNIGHT LOWS BASED ON CURRENT TEMPERATURE
AND CLOUD COVER TRENDS. LATEST LOCAL WRF AND HRRR GUIDANCE KEEP
PRECIPITATION THAT WAS SPREADING INTO THE OHIO VALLEY TO THE
NORTHWEST OF THE FORECAST AREA THROUGH AT LEAST 12Z/7AM.
CLOUDS CONTINUE TO INCREASE ON SUNDAY AS AN AREA OF LOW PRESSURE
BEGINS TO DEVELOP ALONG THE GULF COAST/LOWER MISSISSIPPI VALLEY IN
RESPONSE TO A DIGGING SOUTHERN STREAM SHORTWAVE EMERGING FROM THE
TROUGH OVER THE SOUTHERN ROCKIES/WESTERN HIGH PLAINS. A BROAD AREA
OF OVERRUNNING PRECIPITATION WILL RACE NORTHEASTWARD THROUGH THE
LOWER TENNESSEE VALLEY DURING THE DAY REACHING OUR WESTERN
FORECAST AREA BY EARLY EVENING.
HIGHS TOMORROW MID-40S TO NEAR 50 AS THE LOWERING/THICKENING
CLOUD COVER OFFSETS WARM ADVECTION. H85 TEMPS +4 TO +7C RANGE BY
00Z MONDAY AS THE PRECIP BEGINS TO ARRIVE WHICH SHOULD ENSURE AN
ALL-LIQUID EVENT FROM THE ONSET... ALTHOUGH VERY BRIEF PERIOD OF
SLEET IN A FEW SHELTERED VALLEYS MAY BE POSSIBLE DUE TO SOME QUICK
EVAPORATIONAL COOLING.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
AS OF 300 PM EDT SATURDAY...
A NORTHERN STREAM TROUGH WILL DROP SOUTH OVER THE PLAINS SUNDAY.
THE NORTHERN STREAM WILL BEGIN TO PHASE WITH THE SOUTHERN STREAM
SUNDAY NIGHT...GENERATING A SURFACE WAVE NEAR THE MOUTH OF THE
MISSISSIPPI RIVER. THIS WAVE WILL THEN TRACK INLAND TOWARDS THE
SOUTHERN APPALACHIAN MOUNTAINS MONDAY MORNING...THEN TO THE NEW
ENGLAND COAST MONDAY EVENING. A COLD FRONT WILL SWEEP ACROSS THE
REGION MONDAY NIGHT. THE UPPER LEVEL TROUGH WILL ACROSS THE OHIO
VALLEY INTO THE MID ATLANTIC REGION TUESDAY.
STORM CONCERNS WILL BE P-TYPE AND AMOUNTS. WARM AIR WILL PUSH
INTO THE REGION AS THIS LOW TRACKS FROM THE GULF COAST SUNDAY
EVENING TO THE MID ATLANTIC MONDAY AFTERNOON. TEMPERATURES AND
THICKNESSES WARM ENOUGH TO HAVE MOSTLY A RAIN EVENT. BY THE TIME
THE COLD AIR ENTERS THE FORECAST AREA LATE MONDAY
AFTERNOON...MOISTURE ASSOCIATED WITH THE SURFACE LOW WILL EXIT THE
REGION. MOISTURE AND COLD AIR AHEAD OF THE UPPER LEVEL TROUGH WILL
THEN BRING MOUNTAIN SNOW SHOWERS AND FLURRIES MONDAY NIGHT INTO
TUESDAY. ACCUMULATIONS PRIMARILY ALONG WESTERN SLOPES WITH
FLURRIES ELSEWHERE TO THE BLUE RIDGE. ACCUMULATIONS UP TO 3 INCHES
LIKELY ALONG WESTERN SLOPES OF SOUTHEASTERN WEST VIRGINIA.
INITIAL PRECIPITATION MAY HAVE P-TYPE CONCERNS AS RESIDUAL INSITU
WEDGE MAY LINGER OVER THE FOOTHILLS AND PIEDMONT COUNTIES INTO
SUNDAY EVENING. RAIN FALLING INTO THIS DRY AIR MAY EXPERIENCE
EVAPORATIVE COOLING AND BRIEFLY FALL AS SLEET...ESPECIALLY IF RAIN
DOES NOT START TO FALL UNTIL THE EVENING HOURS. IF RAIN ADVANCES
OVER AN AREA DURING THE AFTERNOON...THEN PRECIPITATION WILL REMAIN
AS RAIN UNTIL THE FRONT PASSES EAST.
ANOTHER CONCERN WILL FOLLOW BEHIND THE FRONT. PRESSURE RISES AND
AN INCREASING NORTHWEST CROSS BARRIER FLOW WILL BRING WINDY AND
GUSTY CONDITIONS TO THE AREA. WIND GUSTS UP TO 45 MPH ARE POSSIBLE
ALONG RIDGETOPS...ESPECIALLY ALONG THE BLUE RIDGE. A TIGHT
PRESSURE GRADIENTS WILL REMAIN OVER THE REGION INTO TUESDAY. WIND
CHILL VALUES ACROSS THE MOUNTAINS TUESDAY MORNING MAYBE AROUND
ZERO.
TEMPERATURES MONDAY WILL VARY GREATLY FROM THE MID 40S OVER THE
MOUNTAINS TO THE 50S IN THE EAST. MOUNTAIN TEMPERATURES MAY PEAK
EARLY...POSSIBLY FALLING IN THE AFTERNOON DEPENDING ON THE TIMING
OF THE FRONTAL PASSAGE. TEMPERATURES MONDAY NIGHT WILL DROP OFF
DRAMATICALLY AS ARCTIC AIR RUSHES IN. MORNING LOWS ACROSS THE
MOUNTAINS WILL RANGE FROM 10F-20F TO 20F-30F EAST. NOT MUCH OF A
WARMUP ON TUESDAY WITH MOUNTAINS LOCATIONS NOT MAKING IT ABOVE
FREEZING AND IN THE EAST PEAKING OUT IN THE 30S.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 230 PM EST SATURDAY...
A WARM FRONT WILL PASS OVER THE REGION WEDNESDAY...BUT AFTERNOON
TEMPERATURES WILL REMAIN 20F COLDER THAN NORMAL. MORE WARMING ON
THURSDAY WHILE TEMPERATURES REMAIN 10F COLDER THAN NORMAL. A DRY
COLD FRONT WILL TRACK ACROSS THE REGION THURSDAY EVENING.
TEMPERATURES WILL COOL SOME...BUT NOTHING LIKE THE CURRENT COLD
SPELL WE ARE EXPERIENCING THIS WEEKEND. HIGH PRESSURE WILL THEN
KEEP THE AREA DRY INTO SATURDAY.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
AS OF 1140 PM EST SATURDAY...
SURFACE HIGH PRESSURE WAS OVER EAST COAST LATE THIS EVENING. LOW
PRESSURE WILL DEVELOP ALONG THE SOUTHEAST COAST AS THE HIGH MOVES
FARTHER OFFSHORE. A STRONGER LOW PRESSURE SYSTEM WILL CROSS THE
SOUTHERN PLAINS TONIGHT AND SUNDAY. CLOUDS WILL FILL IN ACROSS THE
FORECAST AREA OVERNIGHT. HIGH CONFIDENCE THAT CEILINGS WILL REMAIN
VFR THROUGH MID MORNING.
RAIN WILL MOVE INTO THE MOUNTAINS SUNDAY AFTERNOON. MEDIUM
CONFIDENCE THAT CEILINGS AND VISIBILITIES WILL LOWER TO MVFR
AFTER 00Z/7PM. TIMING COULD BE A BIT FASTER AT KLWB AND KBLF.
EXTENDED DISCUSSION...
THE SOUTHERN PLAINS LOW WILL TRACK THROUGH THE TENNESSEE VALLEY BY
MONDAY MORNING AND INTO SOUTHEAST CANADA BY TUESDAY MORNING. RAIN
WILL BECOME WIDESPREAD ACROSS THE AREA BY LATE SUNDAY NIGHT. SOME
IP/SN POSSIBLE AT THE ONSET. AS THIS SYSTEM MOVES NORTHEAST
SHOULD SEE CIGS/VSBYS SINK TO IFR AT ALL TAF SITES MONDAY WITH
THE POTENTIAL FOR LOWER CEILINGS.
THE COLD FRONT MOVES ACROSS FOR MONDAY AFTERNOON/NIGHT WITH NW
FLOW WORKING MUCH COLDER AIR IN AGAIN...WITH RAIN CHANGING TO
SNOW SHOWERS OVER THE MOUNTAINS...WHILE THE PIEDMONT/FOOTHILLS DRY
OUT. GUSTY WINDS WILL CREATE TURBULENT FLYING CONDITIONS MON NIGHT
AND TUESDAY WITH WIND GUSTS UP TO 40 KNOTS POSSIBLE. VFR EAST AND
STAYING MVFR/IFR IN THE MTNS TIL LATER TUESDAY.
HIGH PRESSURE OVER THE GULF COAST STATES THEN BUILDS EAST ACROSS
THE AREA BY TUESDAY NIGHT WITH VFR CONDITIONS AND DIMINISHING WIND.
&&
.HYDROLOGY...
AS OF 250 PM EST SATURDAY...
FORECAST PRECIPITATION FOR THE UPCOMING EVENT RANGES FROM ABOUT
ONE-HALF /0.50/ INCH OVER THE NORTHERN RIVER BASINS UP TO ABOUT
ONE /1.00/ INCH OVER THE SOUTHERN RIVER BASINS BY THE TIME IT ENDS
LATE MONDAY. THE RAINFALL IS NEEDED AS PRECIPITATION IN NOVEMBER
TO DATE HAS BEEN VERY SCANTY. MOST OF THE COOP NETWORK SITES HAVE
RECEIVED UNDER 0.50 INCHES FOR THE MONTH AND SOME LESS THAN 0.25
INCHES. A SUBSTANTIAL PORTION OF THE PIEDMONT IN OUR CWA IS
ALREADY IN THE ABNORMALLY DRY CATEGORY ON THE WEEKLY U.S. DROUGHT
MONITOR WITH RAINFALL DEFICITS OF 2 TO 4 INCHES OVER THE PAST 60
DAYS. THE DRY PERIOD IS REFLECTED IN DECLINING STREAM FLOWS AS
MONITORED BY THE USGS STREAM GAGING NETWORK AND ALSO BY FALLING
RESERVOIR STORAGE.
&&
.EQUIPMENT...
AS OF 645 PM EST SATURDAY...
THE VISIBILITY SENSOR AT KLYH...LYNCHBURG AIRPORT...WILL BE OUT
OF SERVICE UNTIL MONDAY WHEN TECHNICHIANS WILL REPLACE THE
SENSOR. UNTIL THEN THE VISIBILITY WILL ONLY BE REPORTED WHEN THE
CONTROL TOWER IS STAFFED.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...PC
NEAR TERM...AMS/PC
SHORT TERM...RCS
LONG TERM...RCS
AVIATION...AMS/PC
HYDROLOGY...PC
EQUIPMENT...AMS
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
815 AM MST SUN NOV 16 2014
.SYNOPSIS...
A STORM SYSTEM WILL MOVE QUICKLY THROUGH THE FOUR CORNERS REGION
TODAY BRINGING A SLIGHT CHANCE OF LIGHT SHOWERS EAST OF
PHOENIX...AS WELL AS WINDY CONDITIONS THROUGH FAR WESTERN ARIZONA
AND SOUTHEAST CALIFORNIA. MUCH COOLER AND DRIER CONDITIONS ARE
EXPECTED THROUGH MONDAY WITH WELL BELOW NORMAL TEMPERATURES.
FREEZING TEMPERATURES ARE LIKELY MONDAY MORNING ACROSS THE HIGHER
ELEVATIONS OF SOUTHERN GILA COUNTY. A GRADUAL WARMING TREND IS
EXPECTED THROUGH THE WEEK.
&&
.DISCUSSION...
THE MUCH ADVERTISED COLD FRONT SUBJECTIVELY ALIGNS FROM THE PHOENIX
METRO THROUGH FAR SWRN ARIZONA THIS MORNING...MOST APTLY DEFINED BY
A DISTINCT DEWPOINT DISCONTINUITY AND PRESENCE OF GUSTY MIXED NORTH
WINDS. WINDS CHANNELING DOWN THE COLORADO RIVER VALLEY HAVE BEEN
QUITE STRONG THIS MORNING TAPPING A POST FRONTAL LLJ AND IN MANY
CASES GUSTING TO 40-50 MPH. NUMEROUS REPORTS OF BLOWING DUST HAVE
BEEN NOTED WITH VSBYS LOCALLY BELOW ONE MILE. HAVE ISSUED A BLOWING
DUST ADVISORY IN THE SHORT TERM THROUGH 11 AM WHEN THE STRONGEST
GUSTS SHOULD START TO PARTIALLY ABATE.
ELSEWHERE...A SHORTWAVE AND PV ANOMALY WERE STRENGTHENING OVER NRN
ARIZONA FORCING MORE FOCUSED DEEP ASCENT THROUGH EAST CNTRL ARIZONA.
COLD ADVECTION ALOFT WAS STEEPENING LAPSE RATES AND RADAR ECHOES
WERE OBTAINING A MORE CONVECTIVE LOOKING APPEARANCE. IN
FACT...DESPITE HIGHER FREEZING LEVELS SOME SNOW SHOWERS WERE
REPORTED IN THE MOUNTAINS SURROUNDING THE GLOBE AREA IN SRN GILA
COUNTY AS A RESULT OF THE CONVECTIVE OVERTURNING.
HOWEVER...SUBSIDENCE WAS RAPIDLY DESCENDING SOUTH BEHIND THE
SHORTWAVE AND ANY FURTHER RAIN/SNOW WILL BE SHUNTED SOUTH AND EAST
BEYOND THE LATE MORNING HOURS. UPDATES THIS MORNING INCLUDED SOME
SHORT TERM ADJUSTMENTS TO THE MOST SALIENT GRIDS TO CAPTURE CURRENT
TRENDS.
&&
.PREVIOUS DISCUSSION...
/442 AM MST SUN NOV 16 2014/
A WELL-DEFINED SHORT-WAVE TROUGH IS EVIDENT ON WV IMAGERY DROPPING
STEADILY SOUTHEASTWARD THROUGH SOUTHERN UT. LIGHT PRECIPITATION HAS
DEVELOPED AHEAD OF THE TROUGH AND SOME LIGHTNING STRIKES HAVE EVEN
BEEN DETECTED ACROSS NORTHEASTERN AZ. SHORT-TERM GUIDANCE IS IN
EXCELLENT AGREEMENT THAT ISOLATED SHOWERS WILL INCREASE IN COVERAGE
ACROSS CENTRAL AND EASTERN AZ EARLY THIS MORNING ASSOCIATED WITH A
CONCENTRATED AREA OF VORTICITY-FORCED ASCENT. CONVECTIVE-ALLOWING
MODELS INCLUDING THE HRRR INDICATE THAT PRECIPITATION WILL LIKELY
CLIP SOUTHERN GILA COUNTY...BEFORE STRONG SUBSIDENCE AND DRYING
OVERSPREAD THE REGION LATER THIS MORNING.
BIGGER IMPACT WITH THIS SYSTEM WILL BE THE INCREASE IN WIND BEHIND A
COLD FRONT. LOW-LEVEL PRESSURE GRADIENT WILL BE TIGHT AND WITH A
FAVORABLE TRAJECTORY DOWN THE CO RIVER VALLEY...GUSTS MAY APPROACH
45 MPH DURING THE AFTERNOON IN THESE AREAS. A WIND ADVISORY
CONTINUES FOR THE CO RIVER VALLEY AS WELL AS PORTIONS OF
SOUTHEASTERN CA.
WITH THE FASTER PROGRESSION OF THE SYSTEM...TEMPERATURES FOR THIS
AFTERNOON CONTINUE TO TREND DOWNWARD AS WELL. FORECAST HIGH
TEMPERATURE OF 70 DEGREES IN PHOENIX WOULD BE THE COOLEST MAXIMUM
SINCE EARLY MARCH. DEWPOINTS WILL ALSO LIKELY DROP INTO THE TEENS OR
EVEN SINGLE DIGITS ACROSS MUCH OF THE AREA LATE THIS AFTERNOON AND
THIS EVENING. ALTHOUGH CONDITIONS FOR RADIATIONAL COOLING WILL NOT
BE OPTIMAL DUE TO SOME MIXING...SHELTERED LOCATIONS IN THE HIGHER
ELEVATIONS (INCLUDING THE GLOBE VICINITY) WILL LIKELY OBSERVE
FREEZING TEMPERATURES. GIVEN THAT THIS IS THE FIRST EVENT OF THE
YEAR AND VEGETATION IS MORE SUSCEPTIBLE TO THE COLD...THE FREEZE
WATCH HAS BEEN UPGRADED TO A WARNING FOR SOUTHERN GILA COUNTY
INCLUDING THE GLOBE AREA. EVEN IN THE OUTLYING AREAS OF THE VALLEY
INCLUDING GILBERT AND QUEEN CREEK...TEMPERATURES WILL FALL INTO THE
30S OVERNIGHT.
DRY NORTHWESTERLY FLOW WILL PREDOMINATE MONDAY IN THE WAKE OF THE
TROUGH. AFTER A COLD START TO THE DAY...TEMPERATURES WILL CLIMB TO
AROUND 71 DEGREES IN PHOENIX. REINFORCING SHOT OF DRY AIR WILL
LIKELY OVERSPREAD THE DESERT SOUTHWEST TUESDAY AS A HIGHLY AMPLIFIED
RIDGE MOVES INTO THE GREAT BASIN. THE GENERAL TREND WILL BE TOWARDS
RISING THICKNESSES AND A GRADUAL WARMING TREND ACROSS THE REGION
THROUGH THE WEEK. INTER/INTRA-MODEL INCONSISTENCIES PERSIST LATE IN
THE WEEK WITH REGARD TO THE EVOLUTION OF SEVERAL SMALL PACIFIC
VORTICES. UNCERTAINTY IS ELEVATED DURING THIS PERIOD AND THE
FORECAST HAS BEEN WEIGHTED TOWARDS CLIMATOLOGICAL AVERAGES.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...
A STRONG COLD FRONT WILL TURN VARIABLE TO EASTERLY LIGHT WINDS TO
THE NORTH BETWEEN 15-18Z THIS MORNING ONCE IT PASSES THROUGH THE
AREA. WINDS WILL BECOME GUSTY BY LATE MORNING LASTING THROUGH MUCH
OF THE AFTERNOON BEHIND THE FRONT. SOME LOW VFR CU WILL HANG AROUND
THROUGH MID MORNING...CLOSER TO HIGHER TERRAIN AREAS BEFORE GETTING
SCOURED OUT BY THE ADVANCING COLD FRONT. EXPECT CLEARING FROM THE
WEST BY 18Z AS A DRIER AND MORE SUBSIDENT AIRMASS MOVES IN BEHIND
THE COLD FRONT. WINDS WILL DIMINISH THIS EVENING AND GRADUALLY TURN
TO A MORE EASTERLY HEADING AFTER MIDNIGHT.
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
THE STRONG COLD FRONT IS IN THE PROCESS OF MOVING DOWN THE COLORADO
RIVER VALLEY AND IS ALREADY LEADING TO STRONG GUSTY WINDS AT KBLH.
STRONG NORTHERLY WINDS WILL BECOME MORE WIDESPREAD AFTER SUNRISE AND
PERSIST THROUGH THE AFTERNOON HOURS. THERE IS POTENTIAL FOR SOME
BLOWING DUST/SAND ACROSS THE REGION WHICH MAY REDUCE LONGER RANGE
VSBYS AND PERIODICALLY REDUCE AIRFIELD VSBYS. WINDS WILL GRADUALLY
DIMINISH THIS EVENING AND BECOME LIGHT AFTER MIDNIGHT.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
TUESDAY THROUGH SATURDAY...
PRESSURE GRADIENTS AND WINDS WILL BEGIN TO RELAX TUESDAY IN THE WAKE
OF THE WEEKEND/S COLD FRONT WITH CONTINUED DRY HUMIDITIES. SINGLE
MINIMUM HUMIDITIES WILL SLOWLY IMPROVE INTO THE TEENS FOR THE
MIDDLE OF NEXT WEEK AND THEN INTO THE 20S FOR LATE NEXT WEEK.
TEMPERATURES WILL BE COOLER THROUGH THE PERIOD...OR ACTUALLY RIGHT
AROUND SEASONAL NORMALS.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...WIND ADVISORY UNTIL 5 PM MST THIS AFTERNOON AZZ020-025.
FREEZE WARNING FROM 2 AM TO 9 AM MST MONDAY AZZ024.
CA...WIND ADVISORY UNTIL 4 PM PST THIS AFTERNOON CAZ030>033.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...MO/HIRSCH
AVIATION...KUHLMAN
FIRE WEATHER...NOLTE/KUHLMAN
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
442 AM MST SUN NOV 16 2014
.UPDATE...UPDATED AVIATION DISCUSSION...
&&
.SYNOPSIS...
A STORM SYSTEM WILL MOVE QUICKLY THROUGH THE FOUR CORNERS REGION
TODAY BRINGING A SLIGHT CHANCE OF LIGHT SHOWERS EAST OF
PHOENIX...AS WELL AS WINDY CONDITIONS THROUGH FAR WESTERN ARIZONA
AND SOUTHEAST CALIFORNIA. MUCH COOLER AND DRIER CONDITIONS ARE
EXPECTED THROUGH MONDAY WITH WELL BELOW NORMAL TEMPERATURES.
FREEZING TEMPERATURES ARE LIKELY MONDAY MORNING ACROSS THE HIGHER
ELEVATIONS OF SOUTHERN GILA COUNTY. A GRADUAL WARMING TREND IS
EXPECTED THROUGH THE WEEK.
&&
.DISCUSSION...
A WELL-DEFINED SHORT-WAVE TROUGH IS EVIDENT ON WV IMAGERY DROPPING
STEADILY SOUTHEASTWARD THROUGH SOUTHERN UT. LIGHT PRECIPITATION HAS
DEVELOPED AHEAD OF THE TROUGH AND SOME LIGHTNING STRIKES HAVE EVEN
BEEN DETECTED ACROSS NORTHEASTERN AZ. SHORT-TERM GUIDANCE IS IN
EXCELLENT AGREEMENT THAT ISOLATED SHOWERS WILL INCREASE IN COVERAGE
ACROSS CENTRAL AND EASTERN AZ EARLY THIS MORNING ASSOCIATED WITH A
CONCENTRATED AREA OF VORTICITY-FORCED ASCENT. CONVECTIVE-ALLOWING
MODELS INCLUDING THE HRRR INDICATE THAT PRECIPITATION WILL LIKELY
CLIP SOUTHERN GILA COUNTY...BEFORE STRONG SUBSIDENCE AND DRYING
OVERSPREAD THE REGION LATER THIS MORNING.
BIGGER IMPACT WITH THIS SYSTEM WILL BE THE INCREASE IN WIND BEHIND A
COLD FRONT. LOW-LEVEL PRESSURE GRADIENT WILL BE TIGHT AND WITH A
FAVORABLE TRAJECTORY DOWN THE CO RIVER VALLEY...GUSTS MAY APPROACH
45 MPH DURING THE AFTERNOON IN THESE AREAS. A WIND ADVISORY
CONTINUES FOR THE CO RIVER VALLEY AS WELL AS PORTIONS OF
SOUTHEASTERN CA.
WITH THE FASTER PROGRESSION OF THE SYSTEM...TEMPERATURES FOR THIS
AFTERNOON CONTINUE TO TREND DOWNWARD AS WELL. FORECAST HIGH
TEMPERATURE OF 70 DEGREES IN PHOENIX WOULD BE THE COOLEST MAXIMUM
SINCE EARLY MARCH. DEWPOINTS WILL ALSO LIKELY DROP INTO THE TEENS OR
EVEN SINGLE DIGITS ACROSS MUCH OF THE AREA LATE THIS AFTERNOON AND
THIS EVENING. ALTHOUGH CONDITIONS FOR RADIATIONAL COOLING WILL NOT
BE OPTIMAL DUE TO SOME MIXING...SHELTERED LOCATIONS IN THE HIGHER
ELEVATIONS (INCLUDING THE GLOBE VICINITY) WILL LIKELY OBSERVE
FREEZING TEMPERATURES. GIVEN THAT THIS IS THE FIRST EVENT OF THE
YEAR AND VEGETATION IS MORE SUSCEPTIBLE TO THE COLD...THE FREEZE
WATCH HAS BEEN UPGRADED TO A WARNING FOR SOUTHERN GILA COUNTY
INCLUDING THE GLOBE AREA. EVEN IN THE OUTLYING AREAS OF THE VALLEY
INCLUDING GILBERT AND QUEEN CREEK...TEMPERATURES WILL FALL INTO THE
30S OVERNIGHT.
DRY NORTHWESTERLY FLOW WILL PREDOMINATE MONDAY IN THE WAKE OF THE
TROUGH. AFTER A COLD START TO THE DAY...TEMPERATURES WILL CLIMB TO
AROUND 71 DEGREES IN PHOENIX. REINFORCING SHOT OF DRY AIR WILL
LIKELY OVERSPREAD THE DESERT SOUTHWEST TUESDAY AS A HIGHLY AMPLIFIED
RIDGE MOVES INTO THE GREAT BASIN. THE GENERAL TREND WILL BE TOWARDS
RISING THICKNESSES AND A GRADUAL WARMING TREND ACROSS THE REGION
THROUGH THE WEEK. INTER/INTRA-MODEL INCONSISTENCIES PERSIST LATE IN
THE WEEK WITH REGARD TO THE EVOLUTION OF SEVERAL SMALL PACIFIC
VORTICES. UNCERTAINTY IS ELEVATED DURING THIS PERIOD AND THE
FORECAST HAS BEEN WEIGHTED TOWARDS CLIMATOLOGICAL AVERAGES.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...
A STRONG COLD FRONT WILL TURN VARIABLE TO EASTERLY LIGHT WINDS TO
THE NORTH BETWEEN 15-18Z THIS MORNING ONCE IT PASSES THROUGH THE
AREA. WINDS WILL BECOME GUSTY BY LATE MORNING LASTING THROUGH MUCH
OF THE AFTERNOON BEHIND THE FRONT. SOME LOW VFR CU WILL HANG AROUND
THROUGH MID MORNING...CLOSER TO HIGHER TERRAIN AREAS BEFORE GETTING
SCOURED OUT BY THE ADVANCING COLD FRONT. EXPECT CLEARING FROM THE
WEST BY 18Z AS A DRIER AND MORE SUBSIDENT AIRMASS MOVES IN BEHIND
THE COLD FRONT. WINDS WILL DIMINISH THIS EVENING AND GRADUALLY TURN
TO A MORE EASTERLY HEADING AFTER MIDNIGHT.
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
THE STRONG COLD FRONT IS IN THE PROCESS OF MOVING DOWN THE COLORADO
RIVER VALLEY AND IS ALREADY LEADING TO STRONG GUSTY WINDS AT KBLH.
STRONG NORTHERLY WINDS WILL BECOME MORE WIDESPREAD AFTER SUNRISE AND
PERSIST THROUGH THE AFTERNOON HOURS. THERE IS POTENTIAL FOR SOME
BLOWING DUST/SAND ACROSS THE REGION WHICH MAY REDUCE LONGER RANGE
VSBYS AND PERIODICALLY REDUCE AIRFIELD VSBYS. WINDS WILL GRADUALLY
DIMINISH THIS EVENING AND BECOME LIGHT AFTER MIDNIGHT.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
TUESDAY THROUGH SATURDAY...
PRESSURE GRADIENTS AND WINDS WILL BEGIN TO RELAX TUESDAY IN THE WAKE
OF THE WEEKEND/S COLD FRONT WITH CONTINUED DRY HUMIDITIES. SINGLE
MINIMUM HUMIDITIES WILL SLOWLY IMPROVE INTO THE TEENS FOR THE
MIDDLE OF NEXT WEEK AND THEN INTO THE 20S FOR LATE NEXT WEEK.
TEMPERATURES WILL BE COOLER THROUGH THE PERIOD...OR ACTUALLY RIGHT
AROUND SEASONAL NORMALS.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...WIND ADVISORY UNTIL 5 PM MST THIS AFTERNOON AZZ020-025.
FREEZE WARNING FROM 2 AM TO 9 AM MST MONDAY AZZ024.
CA...WIND ADVISORY UNTIL 4 PM PST THIS AFTERNOON CAZ030>033.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...HIRSCH
AVIATION...KUHLMAN
FIRE WEATHER...NOLTE/KUHLMAN
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
335 AM MST SUN NOV 16 2014
.SYNOPSIS...
A STORM SYSTEM WILL MOVE QUICKLY THROUGH THE FOUR CORNERS REGION
TODAY BRINGING A SLIGHT CHANCE OF LIGHT SHOWERS EAST OF
PHOENIX...AS WELL AS WINDY CONDITIONS THROUGH FAR WESTERN ARIZONA
AND SOUTHEAST CALIFORNIA. MUCH COOLER AND DRIER CONDITIONS ARE
EXPECTED THROUGH MONDAY WITH WELL BELOW NORMAL TEMPERATURES.
FREEZING TEMPERATURES ARE LIKELY MONDAY MORNING ACROSS THE HIGHER
ELEVATIONS OF SOUTHERN GILA COUNTY. A GRADUAL WARMING TREND IS
EXPECTED THROUGH THE WEEK.
&&
.DISCUSSION...
A WELL-DEFINED SHORT-WAVE TROUGH IS EVIDENT ON WV IMAGERY DROPPING
STEADILY SOUTHEASTWARD THROUGH SOUTHERN UT. LIGHT PRECIPITATION HAS
DEVELOPED AHEAD OF THE TROUGH AND SOME LIGHTNING STRIKES HAVE EVEN
BEEN DETECTED ACROSS NORTHEASTERN AZ. SHORT-TERM GUIDANCE IS IN
EXCELLENT AGREEMENT THAT ISOLATED SHOWERS WILL INCREASE IN COVERAGE
ACROSS CENTRAL AND EASTERN AZ EARLY THIS MORNING ASSOCIATED WITH A
CONCENTRATED AREA OF VORTICITY-FORCED ASCENT. CONVECTIVE-ALLOWING
MODELS INCLUDING THE HRRR INDICATE THAT PRECIPITATION WILL LIKELY
CLIP SOUTHERN GILA COUNTY...BEFORE STRONG SUBSIDENCE AND DRYING
OVERSPREAD THE REGION LATER THIS MORNING.
BIGGER IMPACT WITH THIS SYSTEM WILL BE THE INCREASE IN WIND BEHIND A
COLD FRONT. LOW-LEVEL PRESSURE GRADIENT WILL BE TIGHT AND WITH A
FAVORABLE TRAJECTORY DOWN THE CO RIVER VALLEY...GUSTS MAY APPROACH
45 MPH DURING THE AFTERNOON IN THESE AREAS. A WIND ADVISORY
CONTINUES FOR THE CO RIVER VALLEY AS WELL AS PORTIONS OF
SOUTHEASTERN CA.
WITH THE FASTER PROGRESSION OF THE SYSTEM...TEMPERATURES FOR THIS
AFTERNOON CONTINUE TO TREND DOWNWARD AS WELL. FORECAST HIGH
TEMPERATURE OF 70 DEGREES IN PHOENIX WOULD BE THE COOLEST MAXIMUM
SINCE EARLY MARCH. DEWPOINTS WILL ALSO LIKELY DROP INTO THE TEENS OR
EVEN SINGLE DIGITS ACROSS MUCH OF THE AREA LATE THIS AFTERNOON AND
THIS EVENING. ALTHOUGH CONDITIONS FOR RADIATIONAL COOLING WILL NOT
BE OPTIMAL DUE TO SOME MIXING...SHELTERED LOCATIONS IN THE HIGHER
ELEVATIONS (INCLUDING THE GLOBE VICINITY) WILL LIKELY OBSERVE
FREEZING TEMPERATURES. GIVEN THAT THIS IS THE FIRST EVENT OF THE
YEAR AND VEGETATION IS MORE SUSCEPTIBLE TO THE COLD...THE FREEZE
WATCH HAS BEEN UPGRADED TO A WARNING FOR SOUTHERN GILA COUNTY
INCLUDING THE GLOBE AREA. EVEN IN THE OUTLYING AREAS OF THE VALLEY
INCLUDING GILBERT AND QUEEN CREEK...TEMPERATURES WILL FALL INTO THE
30S OVERNIGHT.
DRY NORTHWESTERLY FLOW WILL PREDOMINATE MONDAY IN THE WAKE OF THE
TROUGH. AFTER A COLD START TO THE DAY...TEMPERATURES WILL CLIMB TO
AROUND 71 DEGREES IN PHOENIX. REINFORCING SHOT OF DRY AIR WILL
LIKELY OVERSPREAD THE DESERT SOUTHWEST TUESDAY AS A HIGHLY AMPLIFIED
RIDGE MOVES INTO THE GREAT BASIN. THE GENERAL TREND WILL BE TOWARDS
RISING THICKNESSES AND A GRADUAL WARMING TREND ACROSS THE REGION
THROUGH THE WEEK. INTER/INTRA-MODEL INCONSISTENCIES PERSIST LATE IN
THE WEEK WITH REGARD TO THE EVOLUTION OF SEVERAL SMALL PACIFIC
VORTICES. UNCERTAINTY IS ELEVATED DURING THIS PERIOD AND THE
FORECAST HAS BEEN WEIGHTED TOWARDS CLIMATOLOGICAL AVERAGES.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...
HIGH LEVEL CIRRUS SCT-BKN IN NATURE IS EXPECTED TO STREAM IN FROM
W-NW REMAINING AOA 20KFT LATER TONIGHT AHEAD OF AN APPROACHING PAC
STORM SYSTEM. SFC WINDS TO FOLLOW DIURNALLY DRIVEN HEADINGS THROUGH
THE EVENING WITH MOSTLY LIGHT SPEEDS. THE APPROACHING WEATHER SYSTEM
AND COLD FRONT THROUGH THE GREAT BASIN STATES EARLY SUNDAY AM WILL
LEAD TO ELEVATED EASTERLY WINDS ACROSS THE PHX AREA FOR SUNDAY
AM...MOSTLY AFTER 16/14Z AND LATER INTO THE AM. WINDS WILL THEN
TRANSITION TO NORTHERLY HEADINGS WITH SUSTAINED VALUES PUSHING INTO
THE 10-15KT RANGE BY MIDDAY AND INTO THE AFTN. CENTRAL DESERT TAF
SITES MAY SEE FEW-SCT CU/SC DECKS DEVELOP BY 12Z AS STRONG FORCING
FROM THE SYSTEM MOVES IN...AND BKN CONDITIONS MAY EVEN OCCUR AT
TIMES FROM 12Z THRU 16Z OR SO. BASES GENLY 6-8K FEET. EXPECT
CLEARING FROM THE WEST BY 18Z AS A DRIER AND MORE SUBSIDENT AIRMASS
MOVES IN BEHIND THE COLD FRONT.
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
TONIGHT...MOSTLY CLEAR SKIES AND INCREASING WINDS FOLLOWING TYPICAL
DIURNAL HEADINGS EXPECTED THROUGH 16/10Z OR SO. A STRONG COLD FRONT
WILL MOVE INTO THE AREA AROUND 10-12Z SUNDAY BRINGING STRONG GUSTY
WINDS FOR KBLH AND ELEVATED WINDS FOR KIPL FOR THE DAYTIME HOURS
SUNDAY. WINDS WILL GENLY HOLD NW-N HEADINGS WITH POTENTIAL GUSTS
PUSHING 40KTS FOR KBLH AND 25KTS FOR KIPL THROUGH THE DAY. THERE IS
POTENTIAL FOR SOME BLOWING DUST/SAND ACROSS THE REGION WHICH MAY
REDUCE LONGER RANGE VSBYS AND PERIODICALLY REDUCE AIRFIELD VSBYS.
VSBY REDUCTIONS NOT INCLUDED IN THE 06Z TAF PACKAGE.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
TUESDAY THROUGH SATURDAY...
PRESSURE GRADIENTS AND WINDS WILL BEGIN TO RELAX TUESDAY IN THE WAKE
OF THE WEEKEND/S COLD FRONT WITH CONTINUED DRY HUMIDITIES. SINGLE
MINIMUM HUMIDITIES WILL SLOWLY IMPROVE INTO THE TEENS FOR THE
MIDDLE OF NEXT WEEK AND THEN INTO THE 20S FOR LATE NEXT WEEK.
TEMPERATURES WILL BE COOLER THROUGH THE PERIOD...OR ACTUALLY RIGHT
AROUND SEASONAL NORMALS.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...WIND ADVISORY UNTIL 5 PM MST THIS AFTERNOON AZZ020-025.
FREEZE WARNING FROM 2 AM TO 9 AM MST MONDAY AZZ024.
CA...WIND ADVISORY UNTIL 4 PM PST THIS AFTERNOON CAZ030>033.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...HIRSCH
AVIATION...CB/NOLTE
FIRE WEATHER...NOLTE/KUHLMAN
AREA FORECAST DISCUSSION
NWS TAUNTON MA
1016 AM EST SUN NOV 16 2014
.SYNOPSIS...
HIGH PRESSURE WILL MOVE OFFSHORE THIS AFTERNOON. INTENSIFYING LOW
PRESSURE OVER THE GULF COAST STATES WILL TRACK NORTHEASTWARD OVER
SOUTHERN NEW ENGLAND MONDAY AND MONDAY NIGHT...BRINGING A SOAKING
RAIN TO THE REGION...STARTING AS A LIGHT WINTRY MIX ACROSS THE
INTERIOR. COASTAL AREAS MAY EXPERIENCE DAMAGING WINDS. MAINLY DRY
WEATHER FOLLOWS BEHIND THE FRONT TUESDAY...BUT UNSEASONABLY COLD
AND BLUSTERY CONDITIONS WILL PERSIST FOR MUCH OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
1010 AM UPDATE...
OVERCAST MID LEVEL CLOUDINESS HAS SLOWED TEMPERATURE RISES THROUGH
THE MID MORNING HOURS. HOWEVER THE HRRR MODEL CONTINUES TO SHOW
WINDS COMING AROUND TO THE SOUTHWEST AND TEMPERATURES RESPONDING
BY RISING INTO THE MID 40S IN SOUTHEAST MA WITH UPPER 40S ON THE
ISLANDS AND AROUND 40 IN SOUTHERN NH FOR HIGHS... SO WILL KEEP
FORECAST MAX TEMPS UNCHANGED.
PREVIOUS DISCUSSION...
MODEL CROSS SECTIONS SHOW A PRONOUNCED LAYER OF LOW LEVEL
MOISTURE MOVING UP S COAST THIS AFTERNOON AS WELL...AND THERE MAY
BE ENOUGH INSTABILITY TO GENERATE BRIEF SHOWER OR TWO ACROSS
SOUTHEAST NEW ENGLAND. WILL KEEP MENTION OF ISOLATED OR SCATTERED
SHOWERS NEAR S COAST DURING AFTERNOON...ALTHOUGH ANY SHOWERS THAT
DO OCCUR WILL BE BRIEF AND LIGHT.
FORECAST SOUNDINGS SHOW RATHER DEEP MIXING NEAR S COAST...CAPE COD
AND ISLANDS WHICH SHOULD RESULT IN GUSTS TO 20-25 MPH THIS AFTERNOON.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/...
340 AM UPDATE...
00Z MODELS HAVE TRENDED SLIGHTLY MILDER WITH SYSTEM FOR MON AND
MON NIGHT...AS LOW PRESSURE PASSES OVER SOUTHERN NEW ENGLAND.
POTENTIAL IMPACTS HIGHLIGHTED BELOW...
* WINTRY MIX...
LARGE SCALE PATTERN DOES NOT FAVOR SIGNIFICANT SNOW OR ICE
ACCUMULATION GIVEN LACK OF DOWNSTREAM BLOCKING. NONETHELESS WEAK
PRESSURE GRADIENT COMBINED WITH NORTHERLY 1000 MB AGEOSTROPHIC
FLOW MEANS LOW LEVEL COLD AIR WILL BE SLOW TO ERODE ACROSS
INTERIOR. STILL ANTICIPATE SNOW/SLEET/FREEZING RAIN MIX AT ONSET
EARLY MON MORNING FROM E SLOPES OF BERKSHIRES AND MONADNOCKS INTO
PARTS OF NE CT AND CENTRAL/INTERIOR NE MA. WINTRY MIX WILL
TRANSITION TO RAIN QUICKLY MON MORNING FROM SE TO NW...BUT SHOULD
HOLD ON LONGEST ACROSS W MA AND FAR SW NH.
SNOWFALL AMOUNTS WILL BE AN INCH OR LESS ALONG WITH LIGHT ICING
/UP TO 0.1 INCH/. WE WILL ISSUE A WINTER WEATHER ADVISORY FOR
LOCATIONS WHERE WE ARE MOST CONFIDENT IN WINTRY MIX...INCLUDING E
SLOPES OF BERKSHIRES...N CENTRAL MA AND MOST OF SW NH. SOME
CONCERN THAT FUTURE MODEL RUNS MAY TREND EVEN MILDER...SO WILL NOT
INCLUDE AREAS FARTHER S/E AT THIS TIME AND LET DAY SHIFT GET A
LOOK AT 12Z RUNS.
* STRONG/DAMAGING WINDS...
ALL MODELS HAVE ANOMALOUSLY STRONG LOW LEVEL JET ACROSS SE NEW
ENGLAND LATER MON AND MON EVENING...AS HIGH AS 75KT AT 925-950 MB
AND EVEN 50-60KT DOWN TO 975 MB.
00Z NAM HAS EXCELLENT DEPICTION OF MILDER AIR FLOODING COASTAL
AREAS AND EXPECT TEMPERATURES TO RISE INTO 60S ACROSS RI AND SE
MA LATE IN DAY OR EARLY MON EVENING. ALTHOUGH IT IS USUALLY
DIFFICULT TO GET DAMAGING WINDS ON SW FLOW...THIS LOW LEVEL
WARMING MAY BE ENOUGH TO HELP MIX AT LEAST 50 PERCENT OF THESE
WINDS SPEEDS TO SURFACE /IF NOT A BIT MORE/. SINCE WE HAVE
POTENTIAL FOR DAMAGING WINDS IN RI AND SE MA...WE WILL ISSUE A
HIGH WIND WATCH FOR THESE AREAS.
IN ADDITION...THERE IS ENOUGH INSTABILITY ALOFT /PER SHOWALTER
INDEX/ TO SUPPORT CONVECTIVE ELEMENTS WHICH MAY SERVE TO MIX THESE
STRONGER WINDS DOWN AS WELL.
GREATEST CHANCE OF DAMAGING WINDS IS ALONG THE SOUTH COAST...CAPE
COD AND ISLANDS.
* HEAVY RAINFALL...
STILL LOOKING AT A GOOD SLUG OF MOISTURE COMING UP COAST WITH A
PLUME OF ANOMALOUSLY HIGH /+2 SD/ PRECIPITABLE WATER VALUES. STRONG
JET DYNAMICS AND 850 MB WIND ANOMALIES SHOULD BRING ENHANCED
RAINFALL TO SE NEW ENGLAND ESPECIALLY IF EMBEDDED CONVECTION
DEVELOPS. MINOR URBAN FLOODING WOULD BE MAIN IMPACT...ESPECIALLY
IN TYPICALLY PRONE LOCATIONS. SHOULD ALSO AFFECT MON EVENING
COMMUTE IN PROVIDENCE AND BOSTON.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
HIGHLIGHTS...
* HEAVY RAIN/DAMAGING WIND GUSTS POSS MON EVENING SOUTHEAST SECTIONS
* MAINLY DRY BUT UNSEASONABLY COLD AND BLUSTERY TUE/WED
* A BIT MILDER THU BUT TURNING COLDER AGAIN FRI/SAT
* OVERALL TEMPS WILL AVERAGE WELL BELOW NORMAL THOUGH NEXT SAT
MONDAY NIGHT...
MAIN WAVE OF LOW PRESSURE ASSOCIATED WITH A VERY STRONG COLD FRONT
LOOKS TO PASS SOMEWHERE NORTHWEST OF I-95 MON EVENING. THIS SHOULD
ALLOW THE COASTAL PLAIN TO WARM SECTOR WITH TEMPS RISING INTO THE 60
TO 65 DEGREE RANGE. MEANWHILE...TEMPS WILL BE JAMMED UP IN THE 30S
ACROSS SOUTHWEST NH/NORTHWEST MA WITH A STRONG INVERSION IN PLACE.
THERE ARE TWO MAIN MAIN CONCERNS WE HAVE MONDAY EVENING.
1) POTENTIAL FOR STRONG-DAMAGING WINDS SOUTHEAST NEW ENGLAND COAST
MONDAY EVENING:
GFS/NAM BOTH SHOWING A SOUTHWEST LOW LEVEL JET OF 60 TO 70 KNOTS AT
925 MB ACROSS SOUTHEAST NEW ENGLAND. GIVEN THAT WE EXPECT THIS AREA
TO WARM SECTOR...SOME OF THIS WIND WILL BE ABLE TO MIX DOWN. THIS
WILL BE ESPECIALLY TRUE IF WERE ABLE TO GENERATE ANY ISOLATED
CONVECTION OR DEVELOP A FINE LINE. ITS ALWAYS A BIT UNCERTAIN HOW
MUCH WIND WILL BE ABLE TO BREAK THROUGH THE INVERSION...BUT FEEL ITS
WORTH A HIGH WIND WATCH FOR SOUTHERN RI AND SOUTHEAST MA. AT THE
VERY LEAST...WILL PROBABLY MEET WIND ADVISORY CRITERIA GIVEN ALL THE
MODELS SHOW THIS AREA IN THE WARM SECTOR.
2) HEAVY RAIN/NUISANCE POOR DRAINAGE STREET FLOODING MONDAY EVENING:
GIVEN VERY STRONG FORCING/JET DYNAMICS COUPLED WITH PLENTY OF
MOISTURE AHEAD OF THE FRONT...HEAVY RAIN IS ANTICIPATED MON EVENING.
IN ADDITION...THERE IS THE LOW RISK OF AN ISOLATED THUNDERSTORM OR
TWO ACROSS SOUTHEAST NEW ENGLAND AS SHOWALTER INDICES DROP TO NEAR
ZERO. PROBABLY A BETTER CHANCE THAT WE SEE AT LEAST A FINE LINE
DEVELOP GIVEN VERY STRONG FORCING ALONG THE FRONT.
REGARDLESS...HEAVY RAIN WILL LIKELY RESULT IN SOME NUISANCE POOR
DRAINAGE STREET FLOODING AND THIS MAY IMPACT PART OF THE EVENING
RUSH HOUR. WE ARE NOT ANTICIPATING SIGNIFICANT FLOODING THOUGH SO
NO FLOOD WATCHES WILL BE ISSUED.
BY LATE MONDAY NIGHT...COLD FRONT WILL HAVE CLEARED THE REGION AND
THE MILD TEMPS ACROSS EASTERN NEW ENGLAND WILL FALL BACK DOWN INTO
THE 30S BY DAYBREAK TUE.
TUESDAY AND WEDNESDAY...
UPPER LEVEL RIDGING EXTENDING INTO WESTERN CANADA/ALASKA WILL FORCE
THE POLAR JET TO PLUNGE ABNORMALLY FAR SOUTH INTO THE EASTERN U.S.
UNSEASONABLY COLD CONDITIONS WILL KEEP AFTERNOON MAINLY IN THE 30S
ON TUE AND WED. IN FACT...SOME OF THE HIGH TERRAIN MAY SEE TEMPS
REMAIN BELOW FREEZING ON WED. NORTHWEST WIND GUSTS OF 25 TO 35 MPH
WILL RESULT IN WIND CHILL VALUES IN THE TEENS AND 20S...SO IT WILL
FEEL MORE LIKE JANUARY. MAINLY DRY WEATHER OVER THIS TIME...BUT A
FLURRY OR TWO WILL BE POSSIBLE AT TIMES.
THURSDAY...
FLOW TURNS MORE SOUTHWEST AHEAD OF THE NEXT COLD FRONT. WHILE TEMPS
WILL STILL AVERAGE BELOW NORMAL...THEY WILL BE MILDER THAN WHAT IS
ON TAP FOR TUE/WED. NOT MUCH MOISTURE AHEAD OF THIS FRONT...SO
MAINLY DRY WEATHER OTHER THAN PERHAPS A PASSING SPRINKLE OR FLURRY.
HIGHS WILL BE IN THE UPPER 30S TO THE MIDDLE 40S.
FRIDAY AND SATURDAY...
ANOTHER SHOT OF UNSEASONABLY COLD AIR WILL FOLLOW BEHIND THE NEXT
COLD FRONT. CONSIDERABLE MODEL DIFFERENCES ON TIMING THOUGH WITH
THE GFS COLDEST ON FRI AND ECMWF COLDER ON SAT. IN ADDITION...THE
ECMWF HAS A WEAK WAVE OF LOW PRESSURE CUTTING UNDERNEATH US FRI INTO
EARLY SAT SUGGESTING THE RISK FOR A PERIOD OF SNOW. NOT SURE ON
THIS THOUGH SINCE GFS/GFSENSEMBLES/GGEM DO NOT SHOW THIS SOLUTION AT
ALL. HOWEVER...ECMWF HAS INDICATED THIS FOR A FEW RUNS IN A ROW SO
DO NOT WANT TO COMPLETELY DISMISS IT EITHER.
&&
.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
1510Z UPDATE...
HIGH CONFIDENCE THIS AFTERNOON...MODERATE CONFIDENCE TONIGHT AND
MON.
VFR THROUGH EARLY THIS EVENING WITH MAINLY OVERCAST MID CLOUDINESS.
THE EXCEPTION MIGHT BE THE FAR SOUTHEAST NEW ENGLAND COAST...WHERE
MARGINAL MVFR CIGS MAY DEVELOP SOMETIME THIS AFTERNOON.
MVFR CIGS BECOME MORE WIDESPREAD TONIGHT AS RAIN ARRIVES FROM SW
TO NE...STARTING AS A WINTRY MIX FROM IJD-ORH-LWM AND POINTS N/W.
MIX TRANSITIONS TO RAIN MON MORNING...LAST ACROSS NW MA AND FAR SW
NH BY MIDDAY. NOT LOOKING FOR MORE THAN AN INCH OR TWO OF SLUSHY
ACCUMULATION BUT LIGHT ICING /UNDER 0.25 INCH/ IS EXPECTED.
CLOSER TO COAST...RAIN/FOG THROUGH MUCH OF DAY AS CONDITIONS LOWER
TO IFR BY AFTERNOON. POTENTIAL FOR ISOLATED THUNDER NEAR S COAST
AS WELL AS STRONG SW WINDS GUSTING TO 40KT AND LLWS...AS SW JET
INCREASES TO 65KT AT 2-3KFT.
KBOS TERMINAL...HIGH CONFIDENCE IN TAF. ALL RAIN EXPECTED LATE
TONIGHT INTO MON.
KBDL TERMINAL...MODERATE CONFIDENCE IN TAF. SHOULD SEE FZRA/PL MIX
AT ONSET AROUND 08Z MON BEFORE QUICK TRANSITION TO RAIN AROUND
10Z.
OUTLOOK...MONDAY NIGHT THROUGH FRIDAY...
MONDAY NIGHT...MODERATE CONFIDENCE. MVFR TO IFR CONDITIONS DURING
THE EVENING IN HEAVY RAIN SHOWERS AND PERHAPS A RUMBLE OR TWO OF
THUNDER ACROSS SOUTHEAST NEW ENGLAND. SOUTH TO SOUTHWEST WIND GUSTS
UP TO 45 KNOTS ARE POSSIBLE ACROSS SOUTHEAST NEW ENGLAND. LLWS
EXPECTED ACROSS THE INTERIOR WITH A STRONG LOW LEVEL INVERSION IN
PLACE. CONDITIONS RAPIDLY IMPROVE TO MAINLY VFR AFTER MIDNIGHT.
TUESDAY THROUGH THURSDAY...MODERATE TO HIGH CONFIDENCE. MAINLY
VFR...BUT BRIEF PERIODS OF MVFR CIGS ARE POSSIBLE AT TIMES.
WESTERLY WIND GUSTS OF 30 KNOTS EXPECTED TUE INTO WED.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
* POTENTIALLY DANGEROUS SITUATION ON COASTAL WATERS MON THROUGH
TUE WITH GALE FORCE WINDS AND RAPIDLY BUILDING SEAS *
* GALE FORCE WINDS MAY PERSIST MUCH OF THIS WEEK *
1010 AM UPDATE... HIGH CONFIDENCE TODAY THROUGH MON.
INCREASING SW WINDS THIS AFTERNOON AS HIGH PRESSURE MOVES
OFFSHORE. GUSTS TO 20 KT LIKELY LATE. WINDS SUBSIDE THIS EVENING
AND BECOME LIGHT E/NE BY DAYBREAK MON.
ASIDE FROM SCATTERED SHOWERS THIS AFTERNOON...ESPECIALLY ON S
COASTAL WATERS...STEADY RAIN ARRIVES EARLY MON MORNING AND
PERSISTS THROUGH DAY. MAY SEE AN ISOLATED THUNDERSTORM MON
AFTERNOON/EVENING.
OF MORE IMPORTANCE...WARM FRONT LIFTING N OF WATERS MON SHOULD
BRING STRONG SW WINDS TO WATERS MON AFTERNOON AND NIGHT WITH 40KT
GUSTS POSSIBLE. ISSUING GALE WATCH FOR ALL WATERS...AND DECIDED TO
EXTEND THROUGH TUE TO ALSO COVER STRONG W/NW WINDS BEHIND SYSTEM
AS DETAILED BELOW.
SEAS WILL BUILD RAPIDLY MON EVENING IN RESPONSE TO INCREASING
WINDS. COULD REACH 12 FT ON OUTER WATERS.
OUTLOOK...MONDAY NIGHT THROUGH THURSDAY...
MONDAY NIGHT...MODERATE CONFIDENCE. GALE WATCH ISSUED WITH A STRONG
LOW LEVEL JET AHEAD OF A COLD FRONT MONDAY EVENING. DESPITE THE
INVERSION...HEAVY RAIN AND PERHAPS A FINE LINE WILL BRING THE THE
POTENTIAL FOR A PERIOD OF 35 TO 45 KNOT WIND GUSTS ALL WATERS DURING
THE EVENING.
TUESDAY THROUGH THURSDAY...MODERATE TO HIGH CONFIDENCE.
UNSEASONABLY COLD AIR WILL RESULT IN STEEP LAPSE RATE OVER THE
RELATIVELY MILD OCEAN. THIS WILL BRING A LONG DURATION OF STRONG
SMALL CRAFT TO GALE FORCE WIND GUSTS AT TIMES GIVEN DECENT WINDS
JUST OFF THE DECK. WIND DIRECTION WILL BE FROM THE WEST OR
SOUTHWEST MOST OF THE PERIOD.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...WINTER WEATHER ADVISORY FROM 3 AM TO 1 PM EST MONDAY FOR
MAZ002>004-008-009-026.
HIGH WIND WATCH FROM MONDAY AFTERNOON THROUGH LATE MONDAY
NIGHT FOR MAZ016>024.
NH...WINTER WEATHER ADVISORY FROM 3 AM TO 1 PM EST MONDAY FOR
NHZ011-015.
RI...HIGH WIND WATCH FROM MONDAY AFTERNOON THROUGH LATE MONDAY
NIGHT FOR RIZ002-004>008.
MARINE...GALE WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY EVENING FOR
ANZ231>235-237-250-251-254>256.
GALE WATCH FROM MONDAY AFTERNOON THROUGH LATE MONDAY NIGHT FOR
ANZ230-236.
&&
$$
SYNOPSIS...FRANK/JWD/GAF
NEAR TERM...FRANK/JWD/GAF
SHORT TERM...JWD
LONG TERM...FRANK
AVIATION...FRANK/JWD/GAF
MARINE...FRANK/JWD/GAF
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
546 AM CST SUN NOV 16 2014
.SHORT TERM...
256 AM CST
THROUGH MONDAY...
THE WEAK WAVE THAT BROUGHT SNOW TO NORTHERN IL SATURDAY EVENING
CONTINUED TO WEAKEN AS IT MOVED OVER SOUTHERN MI...AND ANOTHER WAVE
WILL PASS OVER WI TODAY. A COLD FRONT WILL ALSO MOVE THROUGH THE CWA
WITH LIGHT SNOW AND/OR FLURRIES AHEAD OF IT. MOST OF THE AREA SHOULD
SEE A DUSTING TO A COUPLE OF TENTHS OF ADDITIONAL SNOW.
AS THE COLD FRONT AND ASSOCIATED VORT STREAMER MOVE THROUGH THE
CWA...THE UPPER LEVEL JET STREAK STRENGTHENS SLIGHTLY AS DOES OMEGA
SOUTH OF A VAPLO TO PONTIAC LINE. LIGHT SNOW IS EXPECTED SOUTH OF
THIS LINE LATE THIS AFTERNOON INTO THIS EVENING WITH UP TO AN INCH
OF NEW SNOW POSSIBLE.
SNOW DIMINISHES THIS EVENING BUT FLURRIES ARE POSSIBLE ACROSS THE
CWA AS WE SHOULD HAVE SOME SATURATION IN THE DGZ AND FORCING FROM
THE APPROACHING TROUGH/S VORT STREAMERS. THE UPPER LEVEL TROUGH
MOVES OVERHEAD MONDAY AND ITS ASSOCIATED SURFACE LOW PASSES OVER
LAKE SUPERIOR EARLY MONDAY MORNING. GUIDANCE FEATURES SATURATION IN
THE DGZ SO HAVE FLURRIES IN FOR AREAS SOUTH OF I-88. AREAS NORTH OF
I-88 MAY SEE LIGHT SNOW AND CURRENTLY ONLY HAVE A SLIGHT CHANCE OF
SNOW. CONFIDENCE IS LOW IN MEASURABLE SNOW OCCURRING MONDAY. GUSTY
WEST WINDS MOVE IN BEHIND THE COLD FRONT AS WELL WITH GUSTS UP TO 30
MPH.
TEMPS REMAIN BELOW NORMAL WITH HIGHS TODAY IN THE LOW TO MID
30S...BUT TEMPERATURES WILL BE MUCH COLDER MONDAY. LOWS SUNDAY NIGHT
WILL BE IN THE TEENS TO AROUND 20 OVER NW INDIANA...AND MIN WIND
CHILLS WILL BE IN THE SINGLE DIGITS. A FEW OUTLYING AREAS MAY EVEN
SEE WIND CHILLS DIP BELOW ZERO. HIGHS ON MONDAY WILL ONLY BE IN THE
LOW 30S WITH WIND CHILLS IN THE SINGLE DIGITS TO AROUND ZERO.
JEE
&&
.LONG TERM...
256 AM CST
MONDAY NIGHT THROUGH MONDAY...
GUIDANCE CONTINUES TO HAVE THE BULK OF ARCTIC AIR MOVE OVER THE CWA
MONDAY NIGHT...AND LOWERED LOW TEMPS TO THE LOW TEENS DOWNTOWN TO
THE SINGLE DIGITS IN OUTLYING AREAS. GUSTY WEST WINDS PERSIST
OVERNIGHT WITH GUSTS AROUND 25 MPH. THIS WILL RESULT IN VERY COLD
WIND CHILLS EARLY TUESDAY MORNING. LOOKING AT 0 TO -10F DOWNTOWN AND
SOME OUTLYING AREAS WILL BE IN THE -10 TO -15F RANGE.
THE GOOD NEWS IS THE TROUGH SHIFTS EAST TUESDAY WITH HIGHS IN THE
20S AND LIGHTER SOUTHWEST WINDS. WITH UPPER LEVEL VORT STREAMERS
STILL MOVING OVERHEAD...KEPT FLURRIES IN THE FORECAST FOR MOST OF
THE CWA...AND A CHANCE OF LAKE EFFECT SNOW OVER PORTER COUNTY.
A SURFACE LOW PASSES OVER NORTHERN WI LATE TUESDAY NIGHT INTO
WEDNESDAY MORNING WITH ITS COLD FRONT MOVING THROUGH DURING THE DAY.
COULD SEE LIGHT SNOW ALONG THE IL/WI STATE LINE EARLY WEDNESDAY
MORNING AND THEN A SLIGHT CHANCE OF SNOW FOR MOST OF THE CWA DURING
THE DAY. HAVE LOW CONFIDENCE IN ORGANIZED ACCUMULATING SNOW SINCE
GUIDANCE DIFFERS ON HOW FAR NORTH THE LOW WILL BE. THINKING THE
BETTER FORCING FOR SNOW WILL BE ASSOCIATED WITH THE LOW. WEDNESDAY
DOES LOOK SLIGHTLY WARMER WITH HIGHS IN THE LOW 30S.
THE UPPER LEVEL PATTERN DIFFERS GREATLY AMONG GUIDANCE MEMBERS FOR
THE END OF THIS WEEK WITH THE GFS SHOWING A FASTER PROGRESSION. IN
GENERAL AN UPPER LEVEL TROUGH MOVES THROUGH BRINGING ANOTHER ROUND
OF COLD AIR AND A FEW SLIGHT CHANCES OF SNOW. A WARM UP IS STILL IN
STORE LATE THIS WEEK WITH TEMPS ABOVE FREEZING. THIS COULD LEAD TO A
RAIN/SNOW EVENT BUT IT/S MUCH TOO FAR OUT TO MENTION SPECIFICS NOW.
JEE
&&
.CLIMATE...
RECORD TO NEAR-RECORD COLD IS POSSIBLE EARLY NEXT WEEK. HERE ARE
THE CURRENT RECORD TEMPERATURES AT BOTH CHICAGO AND ROCKFORD FOR
MONDAY AND TUESDAY.
...CHICAGO...
RECORD COLDEST HIGH TEMPERATURE:
TUESDAY THE 18TH...22 IN 1903.
RECORD LOW TEMPERATURE:
TUESDAY THE 18TH...8 IN 1880.
WEDNESDAY THE 19TH...10 IN 1894.
...ROCKFORD...
RECORD COLDEST HIGH TEMPERATURE:
TUESDAY THE 18TH...28 IN 1951.
RECORD LOW TEMPERATURE:
TUESDAY THE 18TH...11 IN 1989.
WEDNESDAY THE 19TH...7 IN 1914.
KJB/MTF/IZZI
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 12Z...
* PATCHY LIGHT SNOW THIS MORNING WITH POTENTIAL FOR MVFR CIGS/VIS.
* MVFR CIGS LIKELY THIS AFTERNOON.
RATZER
//DISCUSSION...UPDATED 12Z...
MID-LEVEL DISTURBANCE SHEARING OUT ACROSS IOWA-WISCONSIN TODAY.
ASSOCIATED AREA OF PATCHY LIGHT SNOW AND MAINLY MVFR/OCNL IFR
CIGS AND VIS CONTINUES TO WEAKEN AS IT MOVES EAST INTO ILLINOIS
THIS MORNING...THOUGH WILL LIKELY SEE SOME LIGHT SNOW AND MVFR CIG
DEVELOPMENT THIS MORNING AS AREA OF LIGHT PRECIP MOVES EAST. AREA
OF MORE SUBSTANTIAL SNOW EXPECTED TO DEVELOP SOUTH OF TERMINALS
THIS AFTERNOON ACROSS CENTRAL IL/NORTHERN INDIANA. OTHERWISE...
FLURRIES MAY LINGER THIS AFTERNOON/EVENING AHEAD OF A COLD FRONT
WHICH WILL MOVE THROUGH AROUND MIDNIGHT.
LIGHT SOUTH-SOUTHWEST WINDS WILL GRADUALLY INCREASE TO 5-10 KT
TODAY BEFORE SHIFTING WEST WITH THE COLD FRONTAL PASSAGE TONIGHT.
WEST WINDS BECOME GUSTY MONDAY MORNING AS SURGE OF COLDER AIR
MOVES IN.
RATZER
//ORD AND MDW CONFIDENCE...UPDATED 12Z...
* MEDIUM CONFIDENCE IN LGT SNOW TIMING AND VIS IMPACTS.
* MEDIUM-HIGH CONFIDENCE IN MVFR CIGS.
* HIGH CONFIDENCE OTHER ELEMENTS.
RATZER
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
MONDAY NIGHT...MVFR CIGS/FLURRIES LIKELY. -SHSN POSSIBLE.
TUESDAY...CHANCE OF MVFR CIGS/FLURRIES.
WEDNESDAY...CHANCE OF MVFR CIGS AND SHSN.
THURSDAY THROUGH SATURDAY...PRIMARILY VFR.
RATZER
&&
.MARINE...
230 AM CST
GALE WATCH WILL BE ISSUED FOR LAKE MICHIGAN OPEN WATERS FROM MID-
AFTERNOON MONDAY THROUGH MID-DAY TUESDAY.
MAIN MARINE CONCERN THIS MORNING IS WITH DEVELOPMENT OF GUSTY
WESTERLY WINDS MONDAY THROUGH TUESDAY IN THE WAKE OF A STRONG COLD
FRONT AND DEEPENING LOW PRESSURE WHICH WILL MOVE FROM THE NORTHERN
LAKES EAST AND THEN NORTHEAST ACROSS QUEBEC AND LABRADOR THROUGH
MID-WEEK. TIGHTENING OF THE SURFACE PRESSURE GRADIENT BETWEEN THIS
DEEPENING LOW AND STRONG HIGH PRESSURE BUILDING SOUTHEAST THROUGH
THE PLAINS WILL COMBINE WITH STEEP LOW LEVEL LAPSE RATES OVER THE
LAKE TO PRODUCE WESTERLY GALE FORCE WINDS FROM MONDAY AFTERNOON
THROUGH TUESDAY MORNING. ANOTHER LOW WILL MOVE ACROSS THE NORTHERN
LAKES WEDNESDAY...WITH THE POTENTIAL FOR ANOTHER PERIOD OF GALES
WEDNESDAY AND WEDNESDAY NIGHT. NOT UNTIL LATE IN THE WEEK DOES IT
LOOK LIKE WINDS WILL DIMINISH SIGNIFICANTLY...WITH VARIOUS FORECAST
MODELS EVENTUALLY DEVELOPING HIGH PRESSURE ACROSS THE MIDWEST
FRIDAY.
ILLINOIS/INDIANA NEARSHORE WATERS WILL NEED SMALL CRAFT ADVISORY BY
MID-DAY MONDAY...AND THOUGH HAVE ELECTED TO LEAVE NEARSHORE WATERS
OUT OF THE GALE WATCH IN COLLABORATION WITH NEIGHBORING WFOS AT THIS
TIME...ITS POSSIBLE SCA COULD NEED TO BE UPGRADED TO GALE WARNING.
RATZER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...GALE WATCH...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...3 PM MONDAY TO NOON
TUESDAY.
&&
$$
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
528 AM CST Sun Nov 16 2014
.SHORT TERM...(Today)
ISSUED AT 341 AM CST SUN NOV 16 2014
High pressure sliding off to the east over the Atlantic Seaboard
this morning as a lull in the pressure gradient moves into the
region. Though the sfc pattern is weak, an upper level disturbance
from the desert SW is moving out and across the region today, with
the best chances for snow showers later this afternoon/evening and
into the overnight hours. Weak winds today becoming increasingly
southwesterly ahead of the advancing showers. A larger trof over
the region and backing into the Plains, still associated with some
light snow showers and flurries also making its way across the
region and the Great Lakes. Have some pops in today for the areas
along and north of a line from Havana to Bloomington, mainly during
the first half of the day. The next wave moving into the middle of
the state by mid day from the SW. Latest 00z model runs in the
SREF, the NAM, the GFS, the GEM, the ECMWF...all shifting a bit
further north with the snow accumulation. Models focusing just
north of I-70 corridor between 21z and 00z with the heaviest of the
snowfall, spreading southward and then slowly shifting southward
with the chances for more snowfall beyond 00z. Snowfall totals
close to 2 to 3 inches along and south of a line from Edgar to
Shelbyville...just barely reaching advisory criteria...but with the
first snow of the season, it being somewhat early for the SE, and
the chance for this to make a messy commute early on Monday, have
gone ahead with the headline at this time. Concern with the axis of
the early qpf shifting northward, that another row of counties may
be needed on the north side...but not nearly enough consistency in
the model runs to be comfortable with that. Borderline 1 to 2
inches in counties north of the advisory to a line from Springfield
to Champaign, but being some of the early accumulations, certainly
potential to make a mess.
&&
.LONG TERM...(Tonight through Saturday)
ISSUED AT 341 AM CST SUN NOV 16 2014
Cold in the forecast not letting up. Several shots of cP air dipping
into the region from the north. Cyclonic flow aloft and plenty of
cold air lending to flurries for Monday afternoon. Temperatures on
the back side of that take a significant dive as 850 mb temps drop
into the -7C to -18C range by Monday afternoon. Early Tuesday
morning will be incredibly cold with lows forecast for single digits
and low 10s F. Winds will be up that morning, resulting in wind
chills dipping into the negative single digits before noon...and not
climbing above the single digits through the afternoon.
Temperatures begin to moderate with a more southerly fetch to the
sfc winds on Tues night/Wed, though still well below seasonal norms.
Minor warm again into the weekend...but still below normal and in
advance of yet another potentially snowy weekend. Next chance for
precip was prev on Thursday but now the GFS and ECMWF are starting
to have major conflicts in the passage of the upper trof from Thurs
to Sat...and the forecast blend is masking some of the more radical
differences. Keeping the pop mentions to a minimum and running more
in line with the drier ECMWF for now, as opposed to a more
aggressive GFS. Best chances for precip associated with the wave
after that going into the weekend.
&&
.AVIATION...(For the 12Z TAFS through 12Z Monday morning)
ISSUED AT 520 AM CST SUN NOV 16 2014
Variable cigs and vsbys across the forecast area this morning with
forecast soundings and the latest HRRR suggesting lower cigs will
hold over most of the area thru the afternoon hours as a weather
system pushes to the south of the TAF sites. This will bring
some scattered areas of light snow this morning with a steadier
snowfall developing along and south of a SPI to CMI line with MVFR
and local IFR cigs and vsbys in snow. Further north, mainly MVFR
with a tempo IFR group in this morning with some flurries and most
of the steadier snows staying just south of BMI. Models suggest
the system producing the snow will shift south and east this
evening with a gradual improving trend seen at PIA to VFR conditions
after 05z. Surface winds once again today will not be much of a
factor with south to southwest winds around 10 kts, with winds
becoming westerly tonight with a gradual increase in speeds to 10
to 15 kts in the 05z-08z time frame.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY from 3 PM this afternoon to 6 AM CST
Monday FOR ILZ054>057-061>063-066>068-071>073.
&&
$$
SHORT TERM...HJS
LONG TERM...HJS
AVIATION...Smith
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
636 AM EST SUN NOV 16 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 420 AM EST SUN NOV 16 2014
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS AN ARCTIC BRANCH UPR
TROF CENTERED OVER HUDSON BAY DOWNSTREAM OF A RDG OVER WRN CANADA. A
SHRTWV MOVING E THRU MN IS EMBEDDED IN THE POLAR BRANCH WLY FLOW
DOMINATING THE CONUS AND BRINGING AN AREA OF LIGHT SN TO THE E HALF
OF MN...MUCH OF WI AND SCENTRAL UPR MI EARLY THIS MRNG. ALTHOUGH
THERE IS FAIRLY STRONG DPVA/DEEP LYR QVECTOR CNVGC AND SOME UPR DVGC
CONTRIBUTING TO DEEP MOISTENING ALOFT AND FORCING THIS AREA OF SN...
ONLY WEAK LLVL MSTR INFLOW THAT IS LIMITING PWAT TO NO MORE THAN
ABOUT 0.33 INCH AT GRB /85 PCT OF NORMAL/ AND H7 SPECIFIC HUMIDITY
TO NO MORE THAN ABOUT 1 G/KG IS LIMITING THE OVERALL SN INTENSITY.
SINCE H85 TEMPS ARE ABOUT -14C...THE LLVL WSW FLOW IS BRINGING SOME
LES TO THE KEWEENAW. BUT RATHER DRY NATURE OF THE LLVL AIR IN NRN MN
AS DEPICTED ON THE 00Z INL RAOB APPEARS TO BE LIMITING THE INTENSITY
OF THIS SN. LOOKING FARTHER UPSTREAM IN SCENTRAL CANADA...A VERY
STRONG SHRTWV EMBEDDED IN THE NW ARCTIC BRANCH FLOW IS DIGGING SEWD
NEAR LK WINNIPEG.
MAIN FCST CONCERNS IN THE SHORT TERM ARE SN TRENDS/AMOUNTS OVER
MAINLY THE SE HALF OF THE CWA ASSOCIATED WITH DISTURBANCE THAT WL BE
MOVING THRU WI. FOCUS FOR LATER TNGT SHIFTS TO POTENTIAL FOR MORE SN
OVER MAINLY THE W IN ADVANCE OF SHRTWV NOW NEAR LK WINNIPEG.
TODAY...THE SHRTWV IN MN EARLY THIS MRNG IS PROGGED TO MOVE STEADILY
ENEWD INTO NRN LOWER MI BY 18Z AND THEN INTO SE ONTARIO DURING THE
AFTN. AREA OF DPVA/DEEP LYR QVECTOR CNVGC/UPR DVGC IS FCST TO IMPACT
THE SE CWA THIS MRNG BEFORE EXITING BY 18Z AND GIVING WAY TO SOME
FAIRLY VIGOROUS DNVA/DEEP LYR QVECTOR DVGC. SINCE THE UPR FLOW IS
TENDING TO BACK MORE IN ADVANCE OF THE DIGGING SHRTWV IN SCENTRAL
CANADA AND MODEL TRENDS SHOW THE DYNAMIC FORCING SHIFTED FARTHER TO
THE N AND RADAR TRENDS/SFC OBS INDICATE THE SN AREA IS MOVING
FARTHER TO THE N...INCRSD POPS OVER AREA S OF A LINE FM ABOUT
IRONWOOD TO MARQUETTE. BUT MODEL QPF IS ONLY A COUPLE HUNDREDTHS OF
AN INCH...SO ANY SN ACCUM WL BE ON THE LIGHT SIDE WITH LIMITED
ABSOLUTE MSTR AND POOR SN GROWTH GIVEN ELEVATED AREA OF FORCING WELL
ABOVE LOWER DGZ. THE LARGER SCALE PCPN WL END BY 18Z FOLLOWING THE
EXIT OF THE DYNAMIC SUPPORT. SINCE THE LLVL FLOW IS FCST TO BACK
SLOWLY BUT STEADILY THRU THE DAY IN ADVANCE OF SHRTWV DIGGING SEWD
TOWARD NW MN...EXPECT THE LES OVER THE KEWEENAW EARLY THIS MRNG TO
SHIFT OUT INTO LK SUP. FOR THE MOST PART...THE HIER RES MODELS
INDICATE THE LLVL FLOW WL NOT BACK ENUF TO BRING MUCH IF ANY LES INTO
LUCE/SCHOOLCRAFT COUNTIES TODAY. BUT WL MAINTAIN SOME CHC POPS OVER
THE SE PORTIONS OF THESE COUNTIES LATE TO REFLECT UNCERTAINTY.
OTRW...DESPITE THE MID LVL DRYING/SUBSIDENCE...THE BACKING LLVL FLOW
WL ALLOW SOME LO CLDS IN WI TO MOVE INTO UPR MI...LIMITING THE
POTENTIAL FOR MORE SUNSHINE. THE BEST CHANCE FOR MORE SUNSHINE WL BE
NEAR LK SUP...WHERE THE LLVL SW FLOW WL DOWNSLOPE.
TNGT...AS THE SHRTWV TO THE NW DIGS SEWD TOWARD NW LK SUP AND CLOSES
OFF BY 12Z MON...BAND OF DEEP LYR QVECTOR CNVGC IN THE MSTR STARVED
COMMA TAIL OF THIS FEATURE IS FCST TO SWING ACROSS UPR MI. ONCE
AGAIN...AN ABSENCE OF SGFNT LLVL MOISTENING WL BE AN IMPEDIMENT TO
WIDESPREAD LIGHT SN. THE BEST CHC FOR MORE WIDESPREAD SN WL BE LATE
OVER THE W...WHERE THE COLD FNT/ENHANCED LLVL CNVGC ASSOCIATED WITH
THE SHRTWV WL ARRIVE LATE. ALSO MAINTAINED SOMEWHAT HIER POPS TO THE
E OF MANISTIQUE-NEWBERRY TO ACCOUNT FOR THE POTENTIAL OF SOME LES
OFF LK MI AS THE INCOMING DYNAMICS COINCIDE WITH A LLVL FLOW BACKED
SUFFICIENTLY TO THE SSW FOR SOME LK EFFECT ESPECIALLY IN THE EVNG.
ONCE THIS COMMA TAIL RIBBON OF FORCING PASSES TO THE E LATE...THE
WINDS MAY VEER ENUF TO DIMINISH THIS POTENTIAL OVER THE E.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 349 AM EST SUN NOV 16 2014
A LOW CURRENTLY TO THE NORTHEAST OF LAKE WINNIPEG WILL DROP
SOUTHEAST OVER LAKE SUPERIOR TONIGHT AND BE THE KEY FEATURE IN
BRINGING ANOTHER SHOT OF COLD AIR ALONG WITH A PERIOD OF LAKE EFFECT
SNOW TO THE AREA FOR MONDAY AND TUESDAY.
THERE WILL LIKELY BE A FEW LIGHT SNOW SHOWERS OVER THE WESTERN U.P.
IN ASSOCIATION WITH THE LOW MOVING THROUGH THE AREA AND JUST AHEAD
OF THE SURFACE TROUGH OVER WESTERN LAKE SUPERIOR AND STARTING TO
COME ONSHORE AT 12Z. AS THIS THIS PUSHES THROUGH...WINDS WILL SHIFT
AROUND TO THE NORTHWEST AND LEAD TO STEADILY INCREASING LAKE EFFECT
(DELTA-T VALUES ABOVE 20) OVER THE WESTERN CWA DURING THE MORNING.
DEEP MOISTURE ASSOCIATED WITH THE LOW WILL REALLY SURGE INTO THE
AREA MONDAY AFTERNOON AND REMAIN THROUGH MONDAY NIGHT OVER THE WEST
AND TUESDAY MORNING OVER THE EAST. THE COOLING ALOFT AND DEEP
MOISTURE WILL ALLOW FOR THE LAKE EFFECT SNOW SHOWERS TO UTILIZE THE
LAKE INDUCED EQUILIBRIUM LEVELS IN THE 15-17KFT RANGE. THUS...WOULD
EXPECT THE LAKE EFFECT TO REALLY INCREASE IN THE AFTERNOON OVER THE
WEST HALF. WITH PLENTY OF UPWARD MOTION (LAKE INDUCED CAPE VALUES OF
700-800 J/KG) AND THE PREVIOUSLY MENTIONED MOISTURE/EQL VALUES
SHOULD SUPPORT MODERATE TO HEAVY LAKE EFFECT SNOW. PLUS...WITH A
GOOD PORTION OF THE LOW LEVEL FORCING RIGHT IN THE DGZ...WOULD
EXPECT THE SNOW RATIOS TO BE IN THE LOW-MID 20S (HELD DOWN SOME FROM
THE TRADITIONALLY HIGHER VALUES DUE TO THE STRENGTH OF THE WINDS).
THE FAVORABLE PERIOD OF LAKE EFFECT WILL CONTINUE INTO THE EVENING
AND LEAD TO SNOWFALL AMOUNTS THE SNOWBELTS OVER THE WEST IN THE 5
TO 11 INCH RANGE BY MIDNIGHT MONDAY NIGHT. EXPECT THE SNOW TO
DIMINISH HEADING INTO THE OVERNIGHT HOURS AS THE DEEPER MOISTURE
DEPARTS...BUT STILL SHOULD SEE LIGHT TO MODERATE SNOWFALL INTO
TUESDAY MORNING WITH SNOW RATIOS HELPED BY WEAKER WINDS AND ALL OF
THE CLOUD BEING IN THE DGZ.
THE STRONG LAKE EFFECT/ENHANCED SNOW SHOWERS WILL SHIFT EAST THROUGH
THE AFTERNOON/EVENING INTO NORTH CENTRAL AND EVENTUALLY EASTERN
UPPER MICHIGAN BEHIND THE SURFACE TROUGH. 00Z RUNS LOOK TO HAVE SPED
UP THE ARRIVAL OF THE CONVERGENT BAND OF LAKE ENHANCED SNOW OVER THE
NORTH CENTRAL AND HAVE FOLLOWED THAT IDEA FOR POPS/SNOWFALL MONDAY
NIGHT. MARQUETTE COUNTY WILL BE INTERESTING SINCE THE WIND PROFILE
WOULD SUPPORT NORTH WIND LES AT 850MB AND NORTH-NORTHWEST IN THE
LOWER LEVELS ON MONDAY EVENING BEFORE TRANSITIONING TO GENERALLY
NORTHWEST LAKE EFFECT BY TUESDAY MORNING. THAT NNW WIND DIRECTION
WOULD SUPPORT THE BANDS GINNING INTO THE HIGHER TERRAIN AREAS AND
AIDING SNOWFALL TOTALS. THE CYCLONIC FLOW BEHIND THE LOW WILL
TRANSITION THE LES INTO WESTERN ALGER COUNTY AND WITH COASTAL
CONVERGENCE ALONG THE MARQUETTE COUNTY SHORELINE...WOULD EXPECT
HEAVY LAKE EFFECT SNOW THERE AFTER MIDNIGHT MONDAY NIGHT AND
CONTINUING THROUGH AT LEAST TUESDAY MORNING. THE STRENGTH OF THE
WINDS SHOULD CARRY THE LAKE EFFECT WELL INLAND OVER EAST-CENTRAL
UPPER MICHIGAN...WITH AT LEAST A FEW INCHES OF ACCUMULATION POSSIBLE
IN EASTERN DELTA AND SOUTHWEST SCHOOLCRAFT COUNTIES. FOR MARQUETTE
AND WESTERN ALGER COUNTIES...EXPECT 24HR SNOWFALL TOTALS (MONDAY
AFTERNOON THROUGH TUESDAY MORNING) IN THE 5 TO 11 INCH RANGE
ALSO...WITH THE HIGHEST VALUES OVER THE HURON MOUNTAINS AND WESTERN
ALGER COUNTY. WHILE CONDITIONS BECOME LESS FAVORABLE ON TUESDAY WITH
INVERSION HEIGHTS LOWERING AHEAD OF THE UPPER RIDGE...THE LAKE
FORCING WILL REMAIN IN THE DGZ AND ENABLE THE POTENTIAL FOR SOME
VERY FLUFFY ACCUMULATION AS WINDS BACK TO THE WEST AND EVENTUALLY
SOUTHWEST.
SO HOW TO HANDLE THE POTENTIAL HEADLINES. WILL ISSUE A LAKE
EFFECT SNOW WATCH FOR GOGEBIC/ONTONAGON...NRN. HOUGHTON AND
KEWEENAW COUNTY DUE TO THE EXPECTED IMPACTS MONDAY INTO MONDAY
NIGHT. ALTHOUGH SNOWFALL AMOUNTS WILL LIKELY BE MORE IN THE
ADVISORY RANGE OVER THE KEWEENAW...THOUGHT THE WIND GUSTS IN THE
35-40MPH RANGE WOULD CREATE ENOUGH BLOWING SNOW TO INCLUDE THEM IN
THE WATCH. GOGEBIC/ONTONAGON WILL SEE SLIGHTLY LOWER WINDS BUT A
BETTER OPPORTUNITY TO SEE WARNING SNOWFALL. AS FOR FARTHER
EAST...THINGS GET A LITTLE MORE COMPLICATED. THINK BARAGA/MARQUETTE
ARE SOLID LES ADVISORIES...BUT BELIEVE WESTERN ALGER COUNTY WILL
SEE WARNING SNOWFALL ON MONDAY NIGHT. DEBATED ISSUING A WATCH FOR
ALGER...ESPECIALLY WITH THE ADDED WIND FACTOR...BUT WAS CONCERNED
THERE WOULD BE ASSUMPTIONS MADE THAT MARQUETTE/BARAGA WOULDN/T
EXPERIENCE ANY IMPACTS SINCE THEY WEREN/T IN A WATCH (EVEN THOUGH
THEY WOULD SUPPORT HAVING AN ADVISORY). THEREFORE...HAVE LEFT OUT
FOR NOW...WHICH WILL ALLOW THE DAY SHIFT TO CONVERT THE WATCH OVER
THE WEST TO WARNING/ADVISORY AND START THE ADVISORY TRANSITION TO
THE EAST FOR SOME OF THE OTHER COUNTIES. AT THAT POINT A WATCH
COULD BE ISSUED.
THE UPPER TROUGH DRIVING THIS PERIOD OF COLD AND LAKE EFFECT WILL
SHIFT TO THE EAST ON TUESDAY AFTERNOON/NIGHT...ALLOWING A WEAK HIGH
PRESSURE RIDGE TO BUILD OVER THE AREA FOR TUESDAY NIGHT.
THUS...WOULD EXPECT THE LAKE EFFECT TO TRANSITION TO THE WESTERLY
OR EVEN SOUTHWESTERLY WIND FAVORED LOCATIONS (KEWEENAW AND ALONG THE
LAKE SUPERIOR SHORELINE EAST OF GRAND MARAIS) AS WINDS BACK. ANOTHER
SHORTWAVE DIVING SOUTHEAST THROUGH CENTRAL CANADA ON TUESDAY WILL
DROP INTO THE UPPER GREAT LAKES REGION LATE TUESDAY NIGHT...BRINGING
ANOTHER SURFACE TROUGH THROUGH THE REGION AND USHERING IN COLD AIR
AND LAKE EFFECT FOR WEDNESDAY INTO THURSDAY. WILL LIKELY SEE SOME
SYNOPTIC SNOWFALL WITH THIS SHORTWAVE...BUT GENERALLY A DUSTING TO
AN INCH OF SNOW NEAR THE WISCONSIN BORDER. BEHIND THIS
TROUGH...EXPECT LAKE EFFECT TO OCCUR IN THE WEST-NORTHWEST FAVORED
LOCATIONS. THERE ARE SOME HINTS OF A LINGERING SURFACE TROUGH
DROPPING SOUTHEAST ACROSS EASTERN LAKE SUPERIOR LATE WEDNESDAY
NIGHT...WHICH WOULD SWITCH WINDS TO MORE OF A NORTHWEST OR
NORTH-NORTHWEST DIRECTION OVER THE EAST. OVERALL...LOOKS LIKE LAKE
EFFECT PARAMETERS ON WEDNESDAY NIGHT AND THURSDAY WILL BE SIMILAR TO
THE BEGINNING OF THE WORK WEEK AND LEAD TO THE POTENTIAL FOR ANOTHER
MODERATE-HEAVY LAKE EFFECT SNOW NEAR LAKE SUPERIOR. WILL CONTINUE
TO MENTION THIS PERIOD IN THE HWO/EHWO.
FRIDAY AND SATURDAY...THE UPPER TROUGH AFFECTING THE AREA
WEDNESDAY/THURSDAY WILL SHIFT EAST AND OUT OF THE AREA ON FRIDAY.
THIS WILL LEAD TO TEMPERATURES TRYING TO WARM TOWARDS NORMAL AS A
WEAK UPPER RIDGE MOVES OVER THE AREA. A SURFACE HIGH WILL BRUSH THE
AREA ON FRIDAY KEEPING LAKE EFFECT CONFINED TO THE WESTERLY WIND
LOCATIONS. THERE ARE HINTS IN SOME OF THE MODELS OF A WEAK
DISTURBANCE AFFECTING THE AREA ON FRIDAY NIGHT INTO SATURDAY...BUT
CONFIDENCE IS LOW AT THIS TIME.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 632 AM EST SUN NOV 16 2014
AS AN UPPER DISTURBANCE PASSING THRU THE GREAT LKS SHIFTS TO THE E
OF UPR MI BY THIS AFTN...EXPECT ANY LINGERING -SN TO END THIS MRNG
AT THE TAF SITES. BUT LINGERING LLVL MSTR WL STILL RESULT IN
PREDOMINANT MVFR CIGS EXCEPT AT IWD...WHERE DOWNSLOPING SW FLOW WL
ALLOW FOR A VFR CLD BASE. THE LOWER CIGS AT CMX AND SAW ARE LIKELY
TO IMPROVE TO VFR LATER IN THE AFTN WITH THE ARRIVAL OF SOME DRIER
AIR. THE APRCH OF ANOTHER DISTURBANCE/LO PRES TROF WL BRING THE
THREAT OF MORE SHSN AND CAUSE DETERIORATING CONDITIONS TO AT LEAST
MVFR AT THE WRN CMX/IWD SITES LATER TNGT.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 349 AM EST SUN NOV 16 2014
SOUTHWEST WINDS UP TO 30KTS WILL CONTINUE TODAY AHEAD OF A LOW
PRESSURE SYSTEM JUST TO THE EAST OF LAKE WINNIPEG. THIS SYSTEM WILL
DROP SOUTHEAST AND OVER LAKE SUPERIOR TONIGHT AND THEN SLOWLY EXIT
TO THE EAST ON MONDAY. AS A TROUGH ASSOCIATED WITH THE LOW SWEEPS
ACROSS THE LAKE ON MONDAY...COLD AIR SURGING ACROSS THE RELATIVELY
WARM WATERS OF LAKE SUPERIOR WILL LEAD TO THE POTENTIAL FOR
NORTHWEST GALE FORCE WINDS OF 35 TO 40KTS MONDAY AFTERNOON INTO
TUESDAY MORNING OVER MUCH OF LAKE SUPERIOR. WILL ISSUE A GALE
WATCH TO ACCOUNT FOR THE EXPECTED GALES...SPREADING FROM WEST TO
EAST MONDAY AFTERNOON/EVENING. WINDS WILL GRADUALLY DECREASE TUESDAY
AFTERNOON INTO TUESDAY NIGHT AS A WEAK HIGH PRESSURE RIDGE MOVES
ACROSS THE AREA. ANOTHER TROUGH WILL SWEEP SOUTHEAST ACROSS THE
UPPER GREAT LAKES REGION WEDNESDAY MORNING AND BRING AN INCREASE IN
WINDS OUT OF THE NORTHWEST (UP TO 30KTS) WHICH WILL CONTINUE INTO
THURSDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW WATCH FROM MONDAY MORNING THROUGH TUESDAY
MORNING FOR MIZ001>003-009.
LAKE SUPERIOR...
GALE WATCH FROM LATE MONDAY NIGHT THROUGH TUESDAY AFTERNOON FOR
LSZ267.
GALE WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY AFTERNOON FOR
LSZ265-266.
GALE WATCH FROM MONDAY AFTERNOON THROUGH LATE MONDAY NIGHT FOR
LSZ162.
GALE WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY MORNING FOR
LSZ242>245-263-264.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...SRF
AVIATION...KC
MARINE...SRF
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
942 AM CST Sun Nov 16 2014
.UPDATE:
Issued at 916 AM CST Sun Nov 16 2014
RAP and HRRR models seem to be handling this morning`s snow pretty
well. RAP especially...with a very nice depiction of the moderate
snow band over central/west central Missouri in the omega fields.
The initial band looks to be weakening over our area, but over the
next couple of hours, the 500MB omega ramps back up again late
this morning/early this afternoon over central MO up into east
central. This combined with good low to mid level frontogenesis
should produce another round of moderate and possibly heavy snow
for a couple of hours. Have therefore expanded the advisory
slightly...mainly to keep a consistent message with accumulations
of 1-2 inches through this afternoon.
Carney
&&
.SHORT TERM: (Through Late This Afternoon)
Issued at 355 AM CST Sun Nov 16 2014
The main weather focus through tonight will be yet another quick
hitting minor winter storm system...where is it going...timing...
and how much snow.
The main culprit for today`s weather will be a upper level TROF axis
extending from the upper MS valley to the central High Plains. Add
to the resultant broadscale lift region out ahead of it a
strengthening h300 130kt jet streak and h850-700 frontogenesis and
the ingredients are there for a more organized and broader reaching
accumulating snow event.
Radar shows this already coming together over parts of northwest MO
with snow being reported in the Kansas City area. Models are
anticipating this initial area of snow to weaken as it moves east
into our region, but this will merely be temporary, with the main
brunt...currently over southern KS...to push east-northeastward and
affect our region from late morning thru the afternoon and into
early evening.
The models have done quite a bit of adjusting the past 24-48hrs,
with a decent shift northward with where to track the pcpn, and
based on current obs, this seems well in hand. Frontogenesis will
be the main driver of where the best snow intensities will setup,
and there is excellent consensus on this being over an area along
and south of a line from roughly 30mi north of the I-44 corridor in
MO and 30mi north of the I-70 corridor in IL. Much of the
accumulating snow will fall during the afternoon, but areas in MO
will see the accumulating snow already by late morning while areas
in IL will continue to see some minor additional accums into the
early evening. The forcing will be further enhanced by a
backbuilding h300 jet, especially over southeast MO and southern IL.
With thick clouds in place already, virtually no advection, and
increasing pcpn coverage, temps will struggle to rise much from
where they are now. This fully supports the cooler MAV MOS temps
and have went with for the forecast. This in turn will result in a
snowier pcpn-type forecast than originally anticipated. Have
trimmed the mixed pcpn coverage to just southeast MO and a small
part of southern IL where some sleet and rain will be possible early
in the event...changing to snow during.
Putting it all together, look for a broad area of 1-2" snowfall
amounts along and south of a line from just north of the I-44
corridor in MO and just north of the I-70 corridor in IL. Will
hoist a winter wx advisory for this area. Little to snow accums
expected elsewhere although nearly all locations should see at least
some light snow.
TES
.LONG TERM: (Tonight through Saturday)
Issued at 355 AM CST Sun Nov 16 2014
A longwave upper level TROF will dig and expand into the eastern and
central CONUS on Monday before gradually shifting east and gradually
losing its hold over our region during the week. Look for another
shot of unseasonable cold on Monday and Tuesday with some recovery
towards average for mid to late week, although with the overall
upper pattern the way it is, it will be tough to actually get back
to normal temps.
Have maintained flurries mention for Monday with deep cyclonic flow
and upper level disturbances rotating down.
Another disturbance will move thru Wednesday accompanied by another
cold front, but at this time, it looks to be going thru dry.
Something to watch.
A more significant system for next weekend will affect our area late
Saturday or just beyond into next Sunday. A much warmer atmosphere
by this time should keep the pcpn all liquid.
TES
&&
.AVIATION: (For the 12z TAFs through 12z Monday Morning)
Issued at 535 AM CST Sun Nov 16 2014
Area of SN over ern KS will continue to move ewd this morning
impacting COU around mid morning and SUS/CPS around mid day. As
the SN ends, MVFR cigs are expected to remain for a few hours
before becoming VFR.
Specifics for KSTL: Expect SN to arrive around mid day. Future
updates may need to lower visbys depending on where the heavier
band of SN sets up. Otherwise, SN will come to an end late this
afternoon leaving VFR cigs as the system pulls out of the region.
Tilly
&&
.CLIMATE:
The following are record low maximums and record low minimums for
each of the next 4 days, which corresponds to the expected length
of the current cold spell and record snowfall for St. Louis and
Columbia for Saturday and Sunday when the area is expecting the
first widespread accumulating snowfall of the season.
Date: 11/16 11/17 11/18
St. Louis
Low High: 29/1997 17/1880 25/1880
Low: 13/1959 6/1959 14/1932
Snowfall: 0.1/1997 1.0/1951
Columbia
Low High: 30/1932 23/1959 27/1903
Low: 8/1959 4/1959 8/1891
Snowfall: 4.8/1932 0.1/1989
Quincy
Low High: 28/1997 19/1959 24/1903
Low: 4/1959 3/1959 7/1903
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...WINTER WEATHER ADVISORY until 6 PM CST this evening FOR Callaway
MO-Cole MO-Crawford MO-Franklin MO-Gasconade MO-Lincoln MO-
Moniteau MO-Montgomery MO-Osage MO-Warren MO.
WINTER WEATHER ADVISORY until 9 PM CST this evening FOR Iron MO-
Madison MO-Reynolds MO-St. Francois MO-Ste. Genevieve MO.
WINTER WEATHER ADVISORY until 9 PM CST this evening FOR
Jefferson MO-St. Charles MO-St. Louis City MO-St. Louis MO-
Washington MO.
IL...WINTER WEATHER ADVISORY until 9 PM CST this evening FOR Bond IL-
Clinton IL-Fayette IL-Madison IL-Marion IL-Monroe IL-
Randolph IL-St. Clair IL-Washington IL.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
553 AM CST Sun Nov 16 2014
.SHORT TERM...(Today through Tuesday)
Issued at 345 AM CST SUN NOV 16 2014
Record breaking cold likely early this week...
Regional radars showing plenty of lgt snow across the region this
morning as main upper-level trough and associated cold front
continue to slide through the area. So far snowfall reports through
the overnight have been far and few between....however accumulations
of less than a half inch are likely through the remainder of the
early morning hrs. Fcst becomes a bit more interesting after 12z as
models have trended a tad further north with frontal band QPF axis
that is expected to impact the far southern zones later this morning
into early afternoon. That said...forcing for ascent looks to be
fairly decent as main upper PV lobe slides east through the course of
the day today. Additionally...models show increasing frontogenesis in
the 850-700 hPa layer as the thermal gradient increases thanks to
increasing cold air advection behind aforementioned secondary cold
front. All told...chances look fairly promising for some light
accumulations south of the KC Metro later today.
Initial look earlier this evening suggested we may need another
advisory for far southern zones to account for anticipated snowfall.
After collaboration with both SGF and LSX...have elected to hold off
on issuing any flags as snowfall accumulations will likely barely
eclipse the 1" mark. This decision is also supported by the recently
arriving 6z NAM and latest runs of the HRRR which are now trending a
bit further south than the earlier runs. In any event...can/t rule
out some minor travel problems later today and daytime shift can
issue SPS statements as needed. Further north...except for some
occasional flurries and chilly conditions as highs top out in the
middle to upper 20s.
Beyond this...story quickly turns to bitterly cold temps as the
chilliest airmass of the season descends upon the region following the
passage of another cold front (albeit dry) overnight tonight.
Following its passage...models show the -20C 850 isotherm making its
way south into northern sections of the fcst area during the day on
Monday. This should result in high temps struggling to reach 20
degrees across much of the area which combined with brisk northwest
winds...will result in single digit windchills through the day.
Confidence continues to increase that record cold high temps likely
to be reached on Monday with record lows also likely Tuesday morning
as the mercury easily falls into the single digits (see climate
section below).
Finally by Tuesday...high pressure across the far southern Plains
will begin tracking east which combined with low pressure entering
the northern Plains...should allow low-level winds to change over to
the south. The end result will be daytime highs climbing back into
the upper 20s to lower 30s Tuesday afternoon with the moderation
trend expected to continue through midweek.
.LONG TERM...(Wednesday through Saturday)
Issued at 345 AM CST SUN NOV 16 2014
The extended continues to look cold and dry for the first half of
the extended before precipitation chances increase towards the end
the work week. Models start out in good agreement at the beginning
of the period on Wednesday with the upper level pattern revealing
upper level troughing over the Great Lakes and Ohio River Valley and
upper level ridging over the western CONUS. Northwest flow aloft
will still be in place over the area however, it will relax a bit
from the very cold temperatures that will affect the area on Monday
and Tuesday. Expect highs in the lower 30s to lower 40s. The model
solutions begin to diverge during this time period with the GFS
keeping the area under northwest flow again Thursday before the
pattern becomes more zonal Thursday through Saturday. The EC depicts
a reinforcing upper trough digging through the Midwest Thursday into
Friday which would reinforce the cold pattern in place. The Canadian
is a middle of the road solution. Have maintain a blended solution
to account for models differences.
The models do come into some agreement with the main feature of
interest in the extended in the form of an upper level trough. This
trough will move from the southwestern Conus into the western High
Plains on Saturday. Warm air advection showers will be underway on
Saturday ahead of the system. The main question is how this system
will evolve. The GFS is progressive with this system in moving a
open wave through the area Saturday night into Sunday. The EC digs
and slows the trough as it moves into the Plains Saturday and Sunday
and closes a low in the base of the trough across Oklahoma on
Sunday. this would provide for a colder and prolonged wet solution.
As such, have chance POPs with rain or snow wording in the forecast
for Saturday night and Sunday to account for difference in
solutions.
&&
.AVIATION...(For the 12Z TAFS through 12Z Monday Morning)
Issued at 541 AM CST SUN NOV 16 2014
IFR conditions showing signs on improvement this morning with all 4
sites reporting low-end MVFR cigs. Snow for the most part has ended
with the arrival of drier air that continues to filter into the
region. Expect lingering MVFR cigs through around 15z before clouds
begin to dissipate. Winds through the day will remain from the
northwest between 10-15 kts...before backing to the west by late
afternoon in advance of a secondary cold front that will pass
overnight. Boundary to make its way through the area between 4 and
7z with MVFR clouds returning late as cold air arrives following
frontal passage.
&&
.CLIMATE...
Updated at 345 AM CST SUN NOV 16 2014
Monday
November 17th Current Record Low Forecast High Monday
Record Low Highs High Afternoon
--------------------------------------------------------------------
Kansas City 24 in 1891 21
St. Joseph 26 in 1951 21
Tuesday
November 18th Current Record Low Forecast Low Tuesday
Record Lows Morning
--------------------------------------------------------------------
Kansas City 14 in 1903 7
St. Joseph 16 in 1989 5
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
MO...NONE.
&&
$$
SHORT TERM...32
LONG TERM...73
AVIATION...32
CLIMATE...Cutter
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1028 AM EST SUN NOV 16 2014
.SYNOPSIS...
EXPECT COLD AND QUIET CONDITIONS THIS AFTERNOON...WITH A STORM SYSTEM
MOVING IN TONIGHT BRINGING MIXED PRECIPITATION TO THE AREA INTO
MONDAY. FOLLOWING THIS SYSTEM...ARCTIC AIR AND LAKE EFFECT SNOW
SHOWERS CAN BE EXPECTED THROUGH THE MIDDLE PART OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
1000 AM UPDATE...MADE SOME MINOR ADJUSTMENTS TO TEMPERATURES FOR
AFTERNOON AND HAVE SOME FLURRIES INITIALLY LATE MORNING TAPERING
DOWN. CONSIDERING WINTER WEATHER ADVISORIES FOR MOST OF OUR
FORECAST AREA LATE TONIGHT/MON AM...EXCEPT THE FINGER LAKES. WAITING
FOR MORE 12Z MORNING GUIDANCE AND WILL MAKE A DECISION BY EARLY
AFTERNOON.
645 AM UPDATE...
AS ANTICIPATED...VERY LIGHT FLURRIES HAVE MANAGED TO MATERIALIZE
AS ZONE OF WEAK ISENTROPIC LIFT ALOFT IS PASSING THROUGH. VIRGA
REPRESENTS MOST OF THE RADAR RETURNS...BUT OLEAN AND WELLSVILLE
MANAGED BRIEF FLURRIES...AND NOW ITHACA AS WELL. HRRR AND RUC
FINALLY CAUGHT UP TO IT...BUT THE FLURRIES ARE STILL ABSENT IN THE
MAIN OPERATIONAL SYNOPTIC MODELS. GRIDS TWEAKED WHERE NEEDED TO
MATCH MINOR TEMPERATURE DETAILS AND SUCH...BUT FORECAST ON TRACK.
PREVIOUS DISCUSSION...
FAIRLY QUIET YET COLD CONDITIONS WILL CLOSE OUT THE WEEKEND TODAY.
THOUGH THERE IS DRY AIR IN THE LOWEST FEW THOUSAND FEET...MODEL
SOUNDINGS ESPECIALLY KITH-KSYR LATER THIS MORNING SHOW SATURATION
IN THE 5 TO 15 KFT AGL LAYER...WEAK LIFT...AND NEARLY ISOTHERMAL
DENDRITIC GROWTH TEMPERATURES /ROUGHLY 10 TO 20 BELOW ZERO
CELSIUS/. MINOR ISENTROPIC LIFT ALSO OCCURS ON THE 290-295K
SURFACES...A RESULT OF WARM AIR ADVECTION ALOFT AHEAD OF THE NEXT
SYSTEM. SO DESPITE LACK OF QPF IN OPERATIONAL MODELS...I BELIEVE
ABILITY FOR GENERATING DENDRITE FLURRIES WILL BE THERE...THE
QUESTION IS WILL THEY SURVIVE THEIR TRIP THROUGH THE LOW LEVEL DRY
AIR. I ADDED CHANCE OF FLURRIES FROM FINGER LAKES THROUGH NY
THRUWAY AREAS LATER THIS MORNING...BUT WHATEVER FALLS /IF ANY/
WILL NOT BE MEASURABLE.
HIGHS TODAY GENERALLY UPPER 30S-MID 40S...ROUGHLY 5-8 DEGREES ABOVE
SATURDAY YET STILL A WAYS BELOW CLIMATOLOGY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
430 AM UPDATE...
THE TREND CONTINUES TO BE WARMER WITH EACH PASSING MODEL RUN
REGARDING THE NEXT SYSTEM LATER TONIGHT THROUGH MONDAY AND THAT
WILL TRANSLATE INTO A FASTER CHANGE TO ALL RAIN IN MANY AREAS.
PRECIP STILL ON TRACK TO ARRIVE SHORTLY AFTER MIDNIGHT AND AT THE
ONSET, MOSTLY ALL SNOW FOR EVERYONE. MODEL SOUNDINGS DO SHOW RAIN
AT THE ONSET IN PLACES SUCH AS KAVP. I BELIEVE EVEN HERE HOWEVER
EVAPORATE COOLING SHOULD GIVE A BRIEF PERIOD OF SNOW OR EVEN SOME
ICE PELLETS AT THE START. WARMING ALOFT MOVES IN QUICK WITH MODEL
CONSENSUS SHOWING THE 850 MB 0C LINE UP TO NEAR KBGM BY 12Z AND
APPROACHING KSYR BY 18Z. AT THE SAME TIME BOUNDARY LAYER TEMPS
THAT ARE MARGINAL AT THE START, WILL WARM ESPECIALLY IN THE LOWER
ELEVATIONS. THIS MAKES SENSE GIVEN THE PLACEMENT OF HIGH PRESSURE
OFF THE COAST, NOT IN A GOOD SPOT FOR LOCKING IN COLD AIR.
WITH THAT IN MIND LOOKING FOR A SNOW TRANSITION TO PLAIN RAIN FROM
MORNING (SOUTHEAST) TO AFTERNOON (NORTHWEST), WITH SOME SLEET AND LIMITED
ICING POSSIBLE DURING THAT TRANSITION. HIGHEST SNOW POTENTIAL FAR
NORTHWEST (BATH TO AUBURN TO BOONVILLE LINE) WHERE 0C LINE DOES
NOT MAKE IT UNTIL 18Z MONDAY. EVEN HERE HOWEVER MIX POTENTIAL WILL
CUT DOWN ON SNOWFALL TOTALS AND STILL THINKING IN THE 2 TO 4 INCH
RANGE AT BEST.
BEST POTENTIAL FOR SOME FREEZING RAIN WILL OCCUR EARLIER IN THE
DAY AND THAT WILL FAVOR NORTHEAST PA AND SULLIVAN COUNTY, NY.
NO ICING IS EXPECTED IN WILKES-BARRE/SCRANTON AREA BUT LIGHT ICING IS
POSSIBLE IN THE POCONOS, ALONG WITH WAYNE COUNTY, PA AND
SULLIVAN, NY. THESE ARE TYPICAL COLD SPOTS AND NORMAL LAST HOLD
OUTS FOR COLD AIR. ANY AMOUNT OF ICE JUSTIFIES A WINTER ADVISORY
AND AFTER COORDINATION WITH PHILLY, NYC, AND ALBANY THIS WAS GIVEN
A STRONG CONSIDERATION FOR THESE AREAS ONLY. FARTHER NORTH AND
WEST ICING LOOKS MUCH MORE LIMITED AND SNOWFALL AMOUNTS DO NOT
MEET CRITERIA.
I DECIDED NOT TO DO AN ADVISORY BECAUSE THE WARMING TREND HAS BEEN
SIGNIFICANT ENOUGH THAT OUR ICING PERIOD MAY BE VERY BRIEF AND
PERHAPS EVEN COVERED BY A SPECIAL WEATHER STATEMENT LATER TODAY.
BOTTOM LINE IS THIS FORECAST IS STILL VERY MUCH UP IN THE AIR AND I
FEEL CONFIDENCE WILL BE A BIT BETTER WITH ANOTHER SET OF MODEL
RUNS UNDER OUR BELT. NO MATTER WHAT, ICING AMOUNTS ARE NOT
EXPECTED TO BE VERY MUCH AT ALL.
BY MONDAY EVENING AS THE SYSTEM MOVES OUT, A DRY SLOT SHOULD END
THE PRECIPITATION ACROSS MOST OF THE AREA. WE WILL SEE COLDER AIR
ONT HE BACKSIDE SOME A BRIEF PERIOD OF LIGHT SNOW IS POSSIBLE BUT
AMOUNTS WOULD BE MINIMAL GIVEN THE DRY SLOT.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
415 AM UPDATE...
IT IS MID NOVEMBER SO SOME COLD AIR IS NOT UNUSUAL. HOWEVER...THE
AIR MASS THAT SWINGS THROUGH TUESDAY-WEDNESDAY ACTUALLY IS QUITE A
BIT ANOMALOUS...MORE TYPICAL OF MID WINTER. 500MB HEIGHTS REACH
THREE STANDARD DEVIATIONS BELOW NORMAL...WHILE 1000-500MB
THICKNESS DIVES TO ONLY ABOUT 505 DECAMETERS. HIGHS TUESDAY-
WEDNESDAY MAINLY IN 25-32 DEGREE RANGE...LOWS TUESDAY NIGHT MID
TEENS-LOW 20S. WINDS ALSO FAIRLY STOUT WHICH WILL MAKE SINGLE
DIGIT TO TEENS WIND CHILLS COMMON.
THE NEW SURGE OF ARCTIC AIR WILL MOVE IN VIA WSW FLOW WHICH WILL
DIRECT ACCUMULATING LAKE EFFECT MAINLY NORTH OF OUR AREA INITIALLY
TUESDAY /EXCEPT FOR SOME OF LAKE ERIE SNOW SHOWERS STILL CROSSING
FINGER LAKES TO MOHAWK VALLEY REGIONS TUE MORNING/. THAT BEING
SAID...THE STRONG COLD AIR ADVECTION WILL BE ONE OF THOSE
SITUATIONS WHERE JUST ABOUT EVERY CLOUD WILL BE PRODUCING
DENDRITES...AND THE FORECAST AT LEAST INCLUDES MENTION OF
SCATTERED FLURRIES FOR ALMOST THE WHOLE AREA.
PROSPECTS FOR A PASSING SHORTWAVE LATE TUESDAY...REDIRECTING LAKE
ONTARIO BAND INTO NORTHERN ONEIDA COUNTY /WITH UPSTREAM LAKE-TO-
LAKE CONNECTIONS/...IS BECOMING APPARENT IN LATEST MODEL GUIDANCE
SUITE. IF THIS HOLDS UP...A SIGNIFICANT AMOUNT OF LOW WATER
CONTENT FLUFFY SNOW COULD ACCUMULATE IN NORTHERN ONEIDA COUNTY
TUESDAY NIGHT. WE WILL MONITOR UPCOMING MODELS AND UPDATE FORECAST
ACCORDINGLY IF CONFIDENCE INCREASES. LAKE ERIE MOISTURE WILL ALSO
MOVE BACK ACROSS MUCH OF CENTRAL NEW YORK...INCLUDING POTENTIAL
ACCUMULATIONS TOWARDS STEUBEN/YATES COUNTIES.
PREVIOUS DISCUSSION...
AFTER THU SIGNIFICANT MODEL DIFFERENCES DEVELOP WITH THE EURO
TRACKING A SFC LOW DOWN THE ST LAWRENCE RIVER VALLEY AND THE GFS
KEEPING A COLD MORE W-NW FLOW OF AIR OVER THE REGION. FOR GRIDS
KEPT IDEA OF LES SNOWS DEVELOPING AS THE WINDS TURN MORE NWRLY THU
NGT-SAT SIMILAR TO GFS. THE 12Z EURO WUD SUGGEST A LIGHT SNOW
EVENT FOR MUCH OF NE PA/C NY FRI WITH MORE LES IN ITS WAKE.
&&
.AVIATION /16Z SUNDAY THROUGH THURSDAY/...
12Z UPDATE...
VFR TODAY...THEN DETERIORATING CONDITIONS AFTER THIS EVENING AS
SYSTEM MOVES INTO THE REGION. AHEAD OF THAT SYSTEM...A COUPLE
LAYERS OF CLOUDS AROUND 5 KFT AND 10-12 KFT PASSING THROUGH
TODAY...AND EVEN BRIEFLY SOME NON-RESTRICTIVE LIGHT FLURRIES KITH-
KSYR. CLOUDS THICKEN THIS EVENING...THEN SNOW DEVELOPS 04Z-08Z AND
QUICKLY BECOMES IFR VIS WITH FUEL ALT REQ CIG. KAVP WILL CHANGE TO
-RA SOON AFTER PRECIPITATION BEGINS...BUT -FZRA WILL MIX IN WITH
THE -SN KBGM-KELM AROUND 10Z-12Z. WINDS BECOMING SSW AROUND 10
KTS DURING THE DAY...THEN VARIABLE OR LIGHT SE TONIGHT.
OUTLOOK...
MON-MON NGT...RESTRICTIONS IN MIXED PRECIPITATION THEN BACK TO
SCATTERED SNOW SHOWERS.
TUE TO WED...RESTRICTIONS IN LAKE EFFECT -SHSN...ESP RME AND SYR.
THUR...RESTRICTIONS POSSIBLE AT RME AND SYR OTHERWISE VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DJN/MDP
NEAR TERM...DJN/MDP
SHORT TERM...HEDEN
LONG TERM...DJN/MDP
AVIATION...MDP
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
649 AM EST SUN NOV 16 2014
.SYNOPSIS...
COLD AND QUIET CONDITIONS TODAY...BUT A STORM SYSTEM WILL MOVE IN
TONIGHT BRINGING MIXED PRECIPITATION TO THE AREA INTO MONDAY.
FOLLOWING THIS SYSTEM...ARCTIC AIR AND LAKE EFFECT SNOW SHOWERS
CAN BE EXPECTED THROUGH THE MIDDLE PART OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
645 AM UPDATE...
AS ANTICIPATED...VERY LIGHT FLURRIES HAVE MANAGED TO MATERIALIZE
AS ZONE OF WEAK ISENTROPIC LIFT ALOFT IS PASSING THROUGH. VIRGA
REPRESENTS MOST OF THE RADAR RETURNS...BUT OLEAN AND WELLSVILLE
MANAGED BRIEF FLURRIES...AND NOW ITHACA AS WELL. HRRR AND RUC
FINALLY CAUGHT UP TO IT...BUT THE FLURRIES ARE STILL ABSENT IN THE
MAIN OPERATIONAL SYNOPTIC MODELS. GRIDS TWEAKED WHERE NEEDED TO
MATCH MINOR TEMPERATURE DETAILS AND SUCH...BUT FORECAST ON TRACK.
PREVIOUS DISCUSSION...
FAIRLY QUIET YET COLD CONDITIONS WILL CLOSE OUT THE WEEKEND TODAY.
THOUGH THERE IS DRY AIR IN THE LOWEST FEW THOUSAND FEET...MODEL
SOUNDINGS ESPECIALLY KITH-KSYR LATER THIS MORNING SHOW SATURATION
IN THE 5 TO 15 KFT AGL LAYER...WEAK LIFT...AND NEARLY ISOTHERMAL
DENDRITIC GROWTH TEMPERATURES /ROUGHLY 10 TO 20 BELOW ZERO
CELSIUS/. MINOR ISENTROPIC LIFT ALSO OCCURS ON THE 290-295K
SURFACES...A RESULT OF WARM AIR ADVECTION ALOFT AHEAD OF THE NEXT
SYSTEM. SO DESPITE LACK OF QPF IN OPERATIONAL MODELS...I BELIEVE
ABILITY FOR GENERATING DENDRITE FLURRIES WILL BE THERE...THE
QUESTION IS WILL THEY SURVIVE THEIR TRIP THROUGH THE LOW LEVEL DRY
AIR. I ADDED CHANCE OF FLURRIES FROM FINGER LAKES THROUGH NY
THRUWAY AREAS LATER THIS MORNING...BUT WHATEVER FALLS /IF ANY/
WILL NOT BE MEASURABLE.
HIGHS TODAY GENERALLY UPPER 30S-MID 40S...ROUGHLY 5-8 DEGREES ABOVE
SATURDAY YET STILL A WAYS BELOW CLIMATOLOGY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
430 AM UPDATE...
THE TREND CONTINUES TO BE WARMER WITH EACH PASSING MODEL RUN
REGARDING THE NEXT SYSTEM LATER TONIGHT THROUGH MONDAY AND THAT
WILL TRANSLATE INTO A FASTER CHANGE TO ALL RAIN IN MANY AREAS.
PRECIP STILL ON TRACK TO ARRIVE SHORTLY AFTER MIDNIGHT AND AT THE
ONSET, MOSTLY ALL SNOW FOR EVERYONE. MODEL SOUNDINGS DO SHOW RAIN
AT THE ONSET IN PLACES SUCH AS KAVP. I BELIEVE EVEN HERE HOWEVER
EVAPORATE COOLING SHOULD GIVE A BRIEF PERIOD OF SNOW OR EVEN SOME
ICE PELLETS AT THE START. WARMING ALOFT MOVES IN QUICK WITH MODEL
CONSENSUS SHOWING THE 850 MB 0C LINE UP TO NEAR KBGM BY 12Z AND
APPROACHING KSYR BY 18Z. AT THE SAME TIME BOUNDARY LAYER TEMPS
THAT ARE MARGINAL AT THE START, WILL WARM ESPECIALLY IN THE LOWER
ELEVATIONS. THIS MAKES SENSE GIVEN THE PLACEMENT OF HIGH PRESSURE
OFF THE COAST, NOT IN A GOOD SPOT FOR LOCKING IN COLD AIR.
WITH THAT IN MIND LOOKING FOR A SNOW TRANSITION TO PLAIN RAIN FROM
MORNING (SOUTHEAST) TO AFTERNOON (NORTHWEST), WITH SOME SLEET AND LIMITED
ICING POSSIBLE DURING THAT TRANSITION. HIGHEST SNOW POTENTIAL FAR
NORTHWEST (BATH TO AUBURN TO BOONVILLE LINE) WHERE 0C LINE DOES
NOT MAKE IT UNTIL 18Z MONDAY. EVEN HERE HOWEVER MIX POTENTIAL WILL
CUT DOWN ON SNOWFALL TOTALS AND STILL THINKING IN THE 2 TO 4 INCH
RANGE AT BEST.
BEST POTENTIAL FOR SOME FREEZING RAIN WILL OCCUR EARLIER IN THE
DAY AND THAT WILL FAVOR NORTHEAST PA AND SULLIVAN COUNTY, NY.
NO ICING IS EXPECTED IN WILKES-BARRE/SCRANTON AREA BUT LIGHT ICING IS
POSSIBLE IN THE POCONOS, ALONG WITH WAYNE COUNTY, PA AND
SULLIVAN, NY. THESE ARE TYPICAL COLD SPOTS AND NORMAL LAST HOLD
OUTS FOR COLD AIR. ANY AMOUNT OF ICE JUSTIFIES A WINTER ADVISORY
AND AFTER COORDINATION WITH PHILLY, NYC, AND ALBANY THIS WAS GIVEN
A STRONG CONSIDERATION FOR THESE AREAS ONLY. FARTHER NORTH AND
WEST ICING LOOKS MUCH MORE LIMITED AND SNOWFALL AMOUNTS DO NOT
MEET CRITERIA.
I DECIDED NOT TO DO AN ADVISORY BECAUSE THE WARMING TREND HAS BEEN
SIGNIFICANT ENOUGH THAT OUR ICING PERIOD MAY BE VERY BRIEF AND
PERHAPS EVEN COVERED BY A SPECIAL WEATHER STATEMENT LATER TODAY.
BOTTOM LINE IS THIS FORECAST IS STILL VERY MUCH UP IN THE AIR AND I
FEEL CONFIDENCE WILL BE A BIT BETTER WITH ANOTHER SET OF MODEL
RUNS UNDER OUR BELT. NO MATTER WHAT, ICING AMOUNTS ARE NOT
EXPECTED TO BE VERY MUCH AT ALL.
BY MONDAY EVENING AS THE SYSTEM MOVES OUT, A DRY SLOT SHOULD END
THE PRECIPITATION ACROSS MOST OF THE AREA. WE WILL SEE COLDER AIR
ONT HE BACKSIDE SOME A BRIEF PERIOD OF LIGHT SNOW IS POSSIBLE BUT
AMOUNTS WOULD BE MINIMAL GIVEN THE DRY SLOT.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
415 AM UPDATE...
IT IS MID NOVEMBER SO SOME COLD AIR IS NOT UNUSUAL. HOWEVER...THE
AIR MASS THAT SWINGS THROUGH TUESDAY-WEDNESDAY ACTUALLY IS QUITE A
BIT ANOMALOUS...MORE TYPICAL OF MID WINTER. 500MB HEIGHTS REACH
THREE STANDARD DEVIATIONS BELOW NORMAL...WHILE 1000-500MB
THICKNESS DIVES TO ONLY ABOUT 505 DECAMETERS. HIGHS TUESDAY-
WEDNESDAY MAINLY IN 25-32 DEGREE RANGE...LOWS TUESDAY NIGHT MID
TEENS-LOW 20S. WINDS ALSO FAIRLY STOUT WHICH WILL MAKE SINGLE
DIGIT TO TEENS WIND CHILLS COMMON.
THE NEW SURGE OF ARCTIC AIR WILL MOVE IN VIA WSW FLOW WHICH WILL
DIRECT ACCUMULATING LAKE EFFECT MAINLY NORTH OF OUR AREA INITIALLY
TUESDAY /EXCEPT FOR SOME OF LAKE ERIE SNOW SHOWERS STILL CROSSING
FINGER LAKES TO MOHAWK VALLEY REGIONS TUE MORNING/. THAT BEING
SAID...THE STRONG COLD AIR ADVECTION WILL BE ONE OF THOSE
SITUATIONS WHERE JUST ABOUT EVERY CLOUD WILL BE PRODUCING
DENDRITES...AND THE FORECAST AT LEAST INCLUDES MENTION OF
SCATTERED FLURRIES FOR ALMOST THE WHOLE AREA.
PROSPECTS FOR A PASSING SHORTWAVE LATE TUESDAY...REDIRECTING LAKE
ONTARIO BAND INTO NORTHERN ONEIDA COUNTY /WITH UPSTREAM LAKE-TO-
LAKE CONNECTIONS/...IS BECOMING APPARENT IN LATEST MODEL GUIDANCE
SUITE. IF THIS HOLDS UP...A SIGNIFICANT AMOUNT OF LOW WATER
CONTENT FLUFFY SNOW COULD ACCUMULATE IN NORTHERN ONEIDA COUNTY
TUESDAY NIGHT. WE WILL MONITOR UPCOMING MODELS AND UPDATE FORECAST
ACCORDINGLY IF CONFIDENCE INCREASES. LAKE ERIE MOISTURE WILL ALSO
MOVE BACK ACROSS MUCH OF CENTRAL NEW YORK...INCLUDING POTENTIAL
ACCUMULATIONS TOWARDS STEUBEN/YATES COUNTIES.
PREVIOUS DISCUSSION...
AFTER THU SIGNIFICANT MODEL DIFFERENCES DEVELOP WITH THE EURO
TRACKING A SFC LOW DOWN THE ST LAWRENCE RIVER VALLEY AND THE GFS
KEEPING A COLD MORE W-NW FLOW OF AIR OVER THE REGION. FOR GRIDS
KEPT IDEA OF LES SNOWS DEVELOPING AS THE WINDS TURN MORE NWRLY THU
NGT-SAT SIMILAR TO GFS. THE 12Z EURO WUD SUGGEST A LIGHT SNOW
EVENT FOR MUCH OF NE PA/C NY FRI WITH MORE LES IN ITS WAKE.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
12Z UPDATE...
VFR TODAY...THEN DETERIORATING CONDITIONS AFTER THIS EVENING AS
SYSTEM MOVES INTO THE REGION. AHEAD OF THAT SYSTEM...A COUPLE
LAYERS OF CLOUDS AROUND 5 KFT AND 10-12 KFT PASSING THROUGH
TODAY...AND EVEN BRIEFLY SOME NON-RESTRICTIVE LIGHT FLURRIES KITH-
KSYR. CLOUDS THICKEN THIS EVENING...THEN SNOW DEVELOPS 04Z-08Z AND
QUICKLY BECOMES IFR VIS WITH FUEL ALT REQ CIG. KAVP WILL CHANGE TO
-RA SOON AFTER PRECIPITATION BEGINS...BUT -FZRA WILL MIX IN WITH
THE -SN KBGM-KELM AROUND 10Z-12Z. WINDS BECOMING SSW AROUND 10
KTS DURING THE DAY...THEN VARIABLE OR LIGHT SE TONIGHT.
OUTLOOK...
MON-MON NGT...RESTRICTIONS IN MIXED PRECIPITATION THEN BACK TO
SCATTERED SNOW SHOWERS.
TUE TO WED...RESTRICTIONS IN LAKE EFFECT -SHSN...ESP RME AND SYR.
THUR...RESTRICTIONS POSSIBLE AT RME AND SYR OTHERWISE VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...MDP
NEAR TERM...MDP
SHORT TERM...HEDEN
LONG TERM...DJN/MDP
AVIATION...MDP
AREA FORECAST DISCUSSION
NWS BISMARCK ND
957 AM CST SUN NOV 16 2014
.UPDATE...
ISSUED AT 957 AM CST SUN NOV 16 2014
MSAS ANALYSIS CONTINUES TO INDICATE A 6MB/3HR PRESSURE RISE RACING
SOUTHEAST ACROSS EASTERN MONTANA. THE INITIAL SURGE/ISALLOBARIC
WIND GUSTS HAVE BEEN NEAR 45 MPH. REGIONAL WEBCAMS SHOWED
VISIBILITIES BEING REDUCED BETWEEN ONE TO ONE HALF MILE WITH THE
INITIAL SURGE. HOWEVER...VISIBILITIES WERE IMPROVING BEHIND THE
FRONT WITH BEACH NOW REPORTING 2 MILE VISIBLITIES.
WILL CONTINUE WITH THE CURRENT WINTER WEATHER ADVISORY FOR BLOWING
SNOW AND WIND ADVISORY CONFIGURATION FOR THIS UPDATE. WILL
CONTINUE TO MONITOR CONDITIONS TODAY IN CASE HEADLINES NEED TO BE
UPDATED. OTHERWISE...ONLY UPDATED THE WSW AND NPW TO CHANGE
"SUNDAY" WORDING TO "TODAY". THE UPDATED PRODUCTS HAVE BEEN SENT.
UPDATE ISSUED AT 632 AM CST SUN NOV 16 2014
THE FOCUS FOR THE REMAINDER OF THE MORNING WILL BE ON THE
EVOLUTION OF THE PRESSURE RISE BUBBLE JUST ENTERING NORTHEAST
MONTANA IN THE WAKE OF THE COLD FRONT AS OF 12 UTC. THIS PRESSURE
RISE BUBBLE OBSERVED AROUND 6MB/3 HR...IS STRONGER THAN PREVIOUSLY
FORECAST WITH THE 00 UTC DETERMINISTIC SUITE. THESE STRONGER
PRESSURE RISES ARE NOW BEING CAPTURED BY THE 06 UTC NAM/GFS AND 11
UTC RAP...WHICH PROPAGATE THE RISE BUBBLE DIRECTLY OVER THE
DEEPEST SNOW PACK OF THE SOUTHWEST LATE THIS MORNING. GIVEN THE
POTENTIAL FOR POSSIBLY STRONGER ISALLOBARIC FORCING...THE SOUTHWEST
WILL HAVE TO BE CLOSELY MONITORED SHOULD AN UPGRADE TO A BLIZZARD
WARNING BECOME NECESSARY.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 340 AM CST SUN NOV 16 2014
A WINTER WEATHER ADVISORY AND A WIND ADVISORY CONTINUE TO HEADLINE
THE SHORT TERM PERIOD. A STRONG COLD FRONT WILL PUSH ACROSS THE
NORTH BEGINNING AROUND 12Z AND MAKE ITS WAY TO THE SOUTHERN BORDER
BY 18Z. STRONG WINDS WILL FOLLOW THE FRONT WITH BLOWING/DRIFTING
SNOW IN THE WINTER WEATHER ADVISORY AREA. ONLY CHANGE TO THE ONGOING
WINTER WEATHER ADVISORY WAS TO ADD KIDDER COUNTY SINCE THEIR
SNOWFALL TOTAL LAST WEEKEND WAS COMPARABLE WITH BURLEIGH COUNTY.
GUSTY WINDS ARE SIMILAR IN BOTH LOCATIONS TODAY.
CURRENT WATER VAPOR IMAGERY SHOWS A POTENT SHORTWAVE WITH
SUBSIDENCE/DARKENING SIGNATURE PUSHING INTO SOUTHERN SASKATCHWEAN.
AT THE SURFACE...CURRENT ANALYSIS PLACES 3HR PRESSURE FALLS OF
6MB ACROSS NORTHWEST NORTH DAKOTA. THE COLD FRONT IS APPROXIMATELY
LOCATED FROM KALISPELL MONTANA TO SWIFT CURRENT SASKATCHEWAN...AND
NORTHEAST INTO LAKE WINNIPEG MANITOBA. THE MAXIMUM 3HR PRESSURE
BUBBLE OF 4 TO 5 MB IS LOCATED OVER SOUTHEAST ALBERTA. THE RAP13
HAS A GOOD HANDLE ON THE CURRENT FRONTAL LOCATION AND LOCATION/MAGNITUDE
OF CURRENT PRESSURE FALL/RISE COUPLET. EXPECT THE MAX PRESSURE
FALLS BETWEEN DICKINSON AND BISMARCK BY 12Z...WITH PRESSURE RISES
PUSHING INTO NORTHWEST NORTH DAKOTA BETWEEN 12Z-15Z SIGNIFYING THE
PASSAGE OF THE COLD FRONT. HENCE THE CURRENT TIMING OF THE
AFOREMENTIONED WINTER WEATHER ADVISORY AND WIND ADVISORY ALL LOOK
ON TRACK. OVERALL...AN AVERAGE RANGE OF SUSTAINED/MAX GUSTS PER
NAM/GFS/RAP BUFKIT SOUNDINGS AND THE 80M HRRR SHOWS NORTHWEST
WINDS SUSTAINED BETWEEN 25KT-35KT...AND GUSTS OF 35KT-45KT.
LOW CLOUDS ALONG WITH ISOLATED TO SCATTERED SNOW SHOWERS WILL ALSO
ACCOMPANY THE FRONTAL PASSAGE. ALTHOUGH THE STRONGEST WINDS WILL
EXIT BY EARLY EVENING...WINDS WILL REMAIN GUSTY THROUGH THE NIGHT
WITH LOW LEVEL ADIABATIC MIXING CONTINUING.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 340 AM CST SUN NOV 16 2014
A POTENTIAL MODERATION IN TEMPERATURES LATE THIS WEEK HIGHLIGHTS
THE EXTENDED FORECAST.
THE 00 UTC SUITE IS IN AGREEMENT ON THE ANOMALOUS HIGH AMPLITUDE
UPPER LEVEL PATTERN ACROSS NORTH AMERICA BREAKING DOWN TO A NEAR
ZONAL PATTERN BY NEXT WEEKEND IN A BROAD VERY LOW AMPLITUDE
TROUGH. THIS WOULD SIGNAL A RECOVERY FROM THE ARCTIC TEMPERATURES
TO STILL BELOW NORMAL...YET MORE TOLERABLE HIGHS NEAR FREEZING BY
NEXT WEEKEND. THE EXTENDED FORECAST LOOKS TO BE PRECIPITATION FREE
LACKING THE NEEDED MOISTURE RECOVERY FROM THE ARCTIC AIRMASS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 633 AM CST SUN NOV 16 2014
A STRONG COLD FRONT WILL SWEEP FROM NORTHERN BORDER AT 12Z SUNDAY TO
THE SOUTHERN BORDER BY 18Z SUNDAY. BEHIND THE FRONT EXPECT MVFR CIGS
TO DEVELOP AND REMAIN THROUGH THE DURATION OF THE TAF PERIOD. GUSTY
NORTHWEST WINDS OF 30 TO 45 MPH WILL ALSO DEVELOP BEHIND THE FRONT
WHICH WILL PRODUCE BLOWING/DRIFTING SNOW. EXPECT IFR VSBYS AT KDIK
AND MVFR VSBYS AT KBIS. OVER THE REMAINING TERMINALS...LIGHT SNOW
SHOWERS AND GUSTY WINDS WILL PRODUCE VSBYS AROUND 6SM AT TIMES.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 6 AM CST /5 AM MST/ MONDAY FOR
NDZ017>020-031>034-040>045.
WIND ADVISORY UNTIL 9 PM CST THIS EVENING FOR NDZ001>003-009>011-
021.
WIND ADVISORY UNTIL 9 PM CST THIS EVENING FOR NDZ004-005-012-013-
022-023-025-037-048.
WINTER WEATHER ADVISORY UNTIL 6 AM CST MONDAY FOR NDZ035-036-046-
047-050-051.
&&
$$
UPDATE...TM
SHORT TERM...KS
LONG TERM...AYD
AVIATION...KS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
633 AM CST SUN NOV 16 2014
.UPDATE...
ISSUED AT 632 AM CST SUN NOV 16 2014
THE FOCUS FOR THE REMAINDER OF THE MORNING WILL BE ON THE
EVOLUTION OF THE PRESSURE RISE BUBBLE JUST ENTERING NORTHEAST
MONTANA IN THE WAKE OF THE COLD FRONT AS OF 12 UTC. THIS PRESSURE
RISE BUBBLE OBSERVED AROUND 6MB/3 HR...IS STRONGER THAN PREVIOUSLY
FORECAST WITH THE 00 UTC DETERMINISTIC SUITE. THESE STRONGER
PRESSURE RISES ARE NOW BEING CAPTURED BY THE 06 UTC NAM/GFS AND 11
UTC RAP...WHICH PROPAGATE THE RISE BUBBLE DIRECTLY OVER THE
DEEPEST SNOW PACK OF THE SOUTHWEST LATE THIS MORNING. GIVEN THE
POTENTIAL FOR POSSIBLY STRONGER ISALLOBARIC FORCING...THE SOUTHWEST
WILL HAVE TO BE CLOSELY MONITORED SHOULD AN UPGRADE TO A BLIZZARD
WARNING BECOME NECESSARY.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 340 AM CST SUN NOV 16 2014
A WINTER WEATHER ADVISORY AND A WIND ADVISORY CONTINUE TO HEADLINE
THE SHORT TERM PERIOD. A STRONG COLD FRONT WILL PUSH ACROSS THE
NORTH BEGINNING AROUND 12Z AND MAKE ITS WAY TO THE SOUTHERN BORDER
BY 18Z. STRONG WINDS WILL FOLLOW THE FRONT WITH BLOWING/DRIFTING
SNOW IN THE WINTER WEATHER ADVISORY AREA. ONLY CHANGE TO THE ONGOING
WINTER WEATHER ADVISORY WAS TO ADD KIDDER COUNTY SINCE THEIR
SNOWFALL TOTAL LAST WEEKEND WAS COMPARABLE WITH BURLEIGH COUNTY.
GUSTY WINDS ARE SIMILAR IN BOTH LOCATIONS TODAY.
CURRENT WATER VAPOR IMAGERY SHOWS A POTENT SHORTWAVE WITH
SUBSIDENCE/DARKENING SIGNATURE PUSHING INTO SOUTHERN SASKATCHWEAN.
AT THE SURFACE...CURRENT ANALYSIS PLACES 3HR PRESSURE FALLS OF
6MB ACROSS NORTHWEST NORTH DAKOTA. THE COLD FRONT IS APPROXIMATELY
LOCATED FROM KALISPELL MONTANA TO SWIFT CURRENT SASKATCHEWAN...AND
NORTHEAST INTO LAKE WINNIPEG MANITOBA. THE MAXIMUM 3HR PRESSURE
BUBBLE OF 4 TO 5 MB IS LOCATED OVER SOUTHEAST ALBERTA. THE RAP13
HAS A GOOD HANDLE ON THE CURRENT FRONTAL LOCATION AND LOCATION/MAGNITUDE
OF CURRENT PRESSURE FALL/RISE COUPLET. EXPECT THE MAX PRESSURE
FALLS BETWEEN DICKINSON AND BISMARCK BY 12Z...WITH PRESSURE RISES
PUSHING INTO NORTHWEST NORTH DAKOTA BETWEEN 12Z-15Z SIGNIFYING THE
PASSAGE OF THE COLD FRONT. HENCE THE CURRENT TIMING OF THE
AFOREMENTIONED WINTER WEATHER ADVISORY AND WIND ADVISORY ALL LOOK
ON TRACK. OVERALL...AN AVERAGE RANGE OF SUSTAINED/MAX GUSTS PER
NAM/GFS/RAP BUFKIT SOUNDINGS AND THE 80M HRRR SHOWS NORTHWEST
WINDS SUSTAINED BETWEEN 25KT-35KT...AND GUSTS OF 35KT-45KT.
LOW CLOUDS ALONG WITH ISOLATED TO SCATTERED SNOW SHOWERS WILL ALSO
ACCOMPANY THE FRONTAL PASSAGE. ALTHOUGH THE STRONGEST WINDS WILL
EXIT BY EARLY EVENING...WINDS WILL REMAIN GUSTY THROUGH THE NIGHT
WITH LOW LEVEL ADIABATIC MIXING CONTINUING.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 340 AM CST SUN NOV 16 2014
A POTENTIAL MODERATION IN TEMPERATURES LATE THIS WEEK HIGHLIGHTS
THE EXTENDED FORECAST.
THE 00 UTC SUITE IS IN AGREEMENT ON THE ANOMALOUS HIGH AMPLITUDE
UPPER LEVEL PATTERN ACROSS NORTH AMERICA BREAKING DOWN TO A NEAR
ZONAL PATTERN BY NEXT WEEKEND IN A BROAD VERY LOW AMPLITUDE
TROUGH. THIS WOULD SIGNAL A RECOVERY FROM THE ARCTIC TEMPERATURES
TO STILL BELOW NORMAL...YET MORE TOLERABLE HIGHS NEAR FREEZING BY
NEXT WEEKEND. THE EXTENDED FORECAST LOOKS TO BE PRECIPITATION FREE
LACKING THE NEEDED MOISTURE RECOVERY FROM THE ARCTIC AIRMASS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 633 AM CST SUN NOV 16 2014
A STRONG COLD FRONT WILL SWEEP FROM NORTHERN BORDER AT 12Z SUNDAY TO
THE SOUTHERN BORDER BY 18Z SUNDAY. BEHIND THE FRONT EXPECT MVFR CIGS
TO DEVELOP AND REMAIN THROUGH THE DURATION OF THE TAF PERIOD. GUSTY
NORTHWEST WINDS OF 30 TO 45 MPH WILL ALSO DEVELOP BEHIND THE FRONT
WHICH WILL PRODUCE BLOWING/DRIFTING SNOW. EXPECT IFR VSBYS AT KDIK
AND MVFR VSBYS AT KBIS. OVER THE REMAINING TERMINALS...LIGHT SNOW
SHOWERS AND GUSTY WINDS WILL PRODUCE VSBYS AROUND 6SM AT TIMES
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 6 AM CST /5 AM MST/ MONDAY FOR
NDZ017>020-031>034-040>045.
WIND ADVISORY UNTIL 9 PM CST THIS EVENING FOR NDZ001>003-009>011-
021.
WIND ADVISORY FROM NOON TODAY TO 9 PM CST THIS EVENING FOR
NDZ004-005-012-013-022-023-025-037-048.
WINTER WEATHER ADVISORY FROM NOON TODAY TO 6 AM CST MONDAY FOR
NDZ035-036-046-047-050-051.
&&
$$
UPDATE...AYD
SHORT TERM...KS
LONG TERM...AYD
AVIATION...KS
AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
221 PM EST SUN NOV 16 2014
...SLIGHT RISK OF SEVERE THUNDERSTORMS MONDAY AFTERNOON AND
EVENING...
...MUCH COLDER TUESDAY AND WEDNESDAY WITH A HARD FREEZE EXPECTED FOR
INLAND SOUTHEAST GEORGIA AND THE SUWANNEE VALLEY WEDNESDAY MORNING...
.NEAR TERM /THROUGH TONIGHT/...
THE WEDGE ACROSS THE REGION BEGINS TO BREAK DOWN AND LIFT NORTHWARD
AS THE NEXT OF THE MUCH HERALDED UPPER LEVEL TROUGHS-COLD AIR
OUTBREAKS BEGINS TO DROP SOUTHEAST TOWARD THE AREA. WINDS WILL REMAIN
LIGHT THIS AFTERNOON INTO TONIGHT WITH ONLY SCATTERED TO BROKEN
CLOUD COVERAGE THIS EVENING. AS RADIATIONAL COOLING AND EARLY MIXING
COMBINE WE SHOULD SEE PATCHY FOG ACROSS THE INTERIOR AREAS AFTER
MIDNIGHT. RIGHT NOW KEEP THE LOWEST VISIBILITIES IN THE 08-13 UTC
RANGE FOR TOMORROW MORNING BUT IT COULD BE EARLIER WITH FOG LIFTING
AFTER 10 UTC AS STRONGER WINDS ARE FORECAST BY THE MODELS. RIGHT NOW
AM GOING TO ASSUME THE MODELS ARE OVER FORECASTING THE LOW LEVEL
FLOW OVERNIGHT. A FEW SHOWERS ARE POSSIBLE LATE OVERNIGHT AHEAD
OF THE FORECASTED SQUALL LINE.
.SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/...
MONDAY/MONDAY NIGHT...AN ARCTIC COLD FRONT WILL APPROACH SE GA
MONDAY MORNING...ENTERING SE GA MONDAY AFTN...THEN CROSSING NE FL
MONDAY EVENING...EXITING TO THE SOUTH BY EARLY MORNING TUESDAY.
INITIAL SHOWERS ALONG A PRE-FRONTAL TROUGH WILL ENTER SE GA BY
LATE MONDAY MORNING SPREADING INTO NE FL IN THE AFTN. MODELS
CONTINUE TO POOL MOISTURE...ALONG WITH SUFFICIENT INSTABILITY AND
DEEP LAYER SHEAR TO SUPPORT A LINE OF THUNDERSTORMS...SOME OF
WHICH WILL BE CAPABLE LOCALLY DAMAGING WINDS. GIVEN SOME
UNCERTAINTY...WILL USE GUSTY WIND WORDING WITH THE STORMS MONDAY
AFTN/EARLY EVENING BEFORE THE MID LEVEL SUPPORT DIMINISHES LATER
IN THE EVENING. PRECIP WILL QUICKLY DIMINISH NW TO SE OVERNIGHT
MONDAY NIGHT AS THE FRONT EXITS TO THE SOUTH. EXPECT AREAL
AVERAGE RAINFALL TOTALS BETWEEN ONE-HALF AND ONE INCH. OUTSIDE
OF STORMS...A TIGHTENING PRESSURE GRADIENT AHEAD OF THE FRONT WILL
PRODUCE BREEZY/LOCALLY WINDY CONDITIONS MONDAY AFTN. WARM AIR WILL
SURGE AHEAD OF THE ARCTIC FRONT MONDAY AFTN...WITH HIGHS IN THE
70S ALONG AND WEST OF I-75...WITH UPPER 70S/LOWER 80S ALONG THE
I-95 CORRIDOR. CHILLY AIR WILL BEGIN TO WORK IN MONDAY NIGHT
BEHIND THE COLD FRONT...WITH LOWS IN THE 30S FAR INLAND WITH 40S
CLOSER TO THE COAST.
TUESDAY/TUESDAY NIGHT...MUCH COLDER AIR WILL POUR INTO THE REGION
WITH HIGHS STRUGGLING TO RISE INTO THE LOWER 50S FOR MOST AREAS
WITH FAR INTERIOR SE GA LIKELY NOT GETTING OUT OF THE UPPER 40S.
IN ADDITION...BREEZY NW WINDS WILL ADD TO THE CHILL DESPITE
SKIES BECOMING SUNNY AREA WIDE BY AFTN. COLD ADVECTION WILL
MAXIMIZE TUESDAY NIGHT SETTING THE STAGE FOR THE COLDEST NIGHT
SINCE LAST WINTER. LATEST MODEL GUIDANCE IS DEPICTING A HARD
FREEZE FOR MOST AREAS WEST OF HIGHWAY 301...WITH LOWER 20S
POSSIBLE ACROSS FAR INTERIOR SE GA INTO THE SUWANNEE VALLEY.
LOCATIONS ALONG THE I-95 CORRIDOR WILL EXPERIENCE SUB-FREEZING
CONDITIONS AS WELL...WITH MID/UPPER 30S ALONG THE IMMEDIATE COAST.
WEDNESDAY/WEDNESDAY NIGHT...HIGH PRESSURE BUILDS INTO THE AREA
FOR DRY CONDITIONS AND LESS WIND. ONLY A SLIGHT WARMUP HOWEVER
WITH HIGHS IN THE LOWER/MID 50S FOR MOST LOCATIONS...WITH ANOTHER
WIDESPREAD FREEZE INLAND WEDNESDAY NIGHT.
.LONG TERM /THURSDAY THROUGH SUNDAY/...
HIGH PRESSURE WILL NUDGE TO THE NE OF THE REGION...ALLOWING FOR
THE MID/UPPER LEVEL FLOW TO BECOME W/SW. THIS WILL RESULT IN A
GRADUAL WARMUP ESPECIALLY AT NIGHT...WITH HIGHS NUDGING UPWARD
INTO THE LOWER TO MID 60S THURSDAY...WITH 70S LIKELY BY SUNDAY.
LOWS WILL WARM TO ABOVE FREEZING AREA WIDE THURSDAY NIGHT...WITH
SLIGHTLY ABOVE NORMAL LOWS FOR THE WEEKEND. WITH LOW LEVEL FLOW
BECOMING ONSHORE LATE WEEK INTO THE WEEKEND...WILL CONTINUE TO
USE SLIGHT CHANCE POPS CLOSE TO THE COAST.
&&
.AVIATION...
SCATTERED TO BROKEN CLOUDINESS THIS AFTERNOON WITH CEILINGS IN THE
3.5-5 KFT RANGE. A LOW CLOUD DECK WILL DEVELOP TONIGHT WITH PATCHY
FOG ACROSS THE INTERIOR SECTIONS OF THE FORECAST AREA. LOOKING FOR
VISIBILITIES TO DROP INTO THE 1-3 MILE RANGE IN GENERAL WITH LOCALLY
LOWER CEILINGS POSSIBLE FOR A BRIEF PERIOD. THE INTERESTING THING
ABOUT TONIGHT WILL BE THE PRIME PERIOD FOR MIXING AS WINDS LOOK TO
INCREASE AS WE APPROACH THE NORMALLY DENSER/THICKER PRE-DAWN FOG.
MODELS ARE INDICATING THE THICKEST FOG SHOULD ACTUALLY BE IN THE
06-10 UTC TIME FRAME WITH INCREASING VISIBILITY TOWARD DAWN. RIGHT
NOW AM GOING TO GO WITH LIGHTER WINDS AND FOG THROUGH DAWN BUT
HONESTLY THE MOST DENSE FOG MIGHT BE EARLIER THAN NORMAL.
GOING TO HOLD OFF ON INTRODUCING SHOWERS AND THUNDERSTORMS FOR
TOMORROW AND WILL JUST KEEP THEM IN THE VICINITY OF THE FIELDS
THROUGH 18 UTC. HRRR IS SHOWING A SOME PRE-SQUALL LINE ACTIVITY BU
THE MAIN SQUALL LINE DOES NOT APPROACH THE FIELDS UNTIL AFTER 18
UTC. NAM12 IS BRING CONVECTION IN A BIT EARLIER ESPECIALLY IN THE
GAINESVILLE AREA.
&&
.MARINE...
CONDITIONS HAVE BRIEFLY IMPROVED OVER THE OFFSHORE WATERS...PERHAPS
UNDER CAUTION CRITERIA. THIS PERIOD WILL BE BRIEFLY LIVED...AS
SOUTHERLIES INCREASE LATE TONIGHT. THUS...WILL USE CAUTION FOR THE
OFFSHORE WATERS. SCA CONDITIONS WILL DEVELOP OFFSHORE MONDAY
EVENING...WITH SCA POSSIBLE FOR THE NEARSHORE WATERS LATE
MONDAY NIGHT/TUESDAY IN THE WAKE OF AN ARCTIC COLD FRONT.
STRONG/LOCALLY SEVERE THUNDERSTORMS WILL ACCOMPANY THE FRONTAL
BOUNDARY LATE MON AFTERNOON AND EVENING. NORTH WINDS WILL SUBSIDE
WEDNESDAY AS HIGH PRESSURE BUILDS OVER THE REGION.
RIP CURRENTS: MODERATE RISK EXPECTED TODAY DUE TO EASTERLY SWELLS.
LOW RISK EXPECTED MONDAY THROUGH MIDWEEK WITH OFFSHORE FLOW.
&&
.FIRE WEATHER...
WINDY CONDITIONS WILL PREVAIL MONDAY AHEAD OF A STRONG COLD
FRONT...BUT WITH RH VALUES HIGH...NO HEADLINES EXPECTED. BREEZY
TO WINDY NW WINDS CAN BE EXPECTED TUESDAY/WEDNESDAY IN THE WAKE
OF THE FRONT. WITH RH VALUES FALLING TO NEAR CRITICAL LEVELS...WILL
MONITOR ERC/FUEL MOISTURE VALUES FOR POSSIBLE HEADLINES. RH
VALUES WILL INCREASE LATE WEEK AS ONSHORE FLOW DEVELOPS.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 60 73 35 48 / 20 90 40 0
SSI 61 76 41 51 / 10 90 80 0
JAX 62 79 40 52 / 10 90 80 0
SGJ 64 81 44 54 / 10 70 80 10
GNV 60 77 42 53 / 10 90 80 10
OCF 61 79 44 55 / 10 80 80 10
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GA...NONE.
AM...NONE.
&&
$$
ALLEN/SANDRIK
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1204 PM CST SUN NOV 16 2014
.SHORT TERM...
256 AM CST
THROUGH MONDAY...
THE WEAK WAVE THAT BROUGHT SNOW TO NORTHERN IL SATURDAY EVENING
CONTINUED TO WEAKEN AS IT MOVED OVER SOUTHERN MI...AND ANOTHER WAVE
WILL PASS OVER WI TODAY. A COLD FRONT WILL ALSO MOVE THROUGH THE CWA
WITH LIGHT SNOW AND/OR FLURRIES AHEAD OF IT. MOST OF THE AREA SHOULD
SEE A DUSTING TO A COUPLE OF TENTHS OF ADDITIONAL SNOW.
AS THE COLD FRONT AND ASSOCIATED VORT STREAMER MOVE THROUGH THE
CWA...THE UPPER LEVEL JET STREAK STRENGTHENS SLIGHTLY AS DOES OMEGA
SOUTH OF A VAPLO TO PONTIAC LINE. LIGHT SNOW IS EXPECTED SOUTH OF
THIS LINE LATE THIS AFTERNOON INTO THIS EVENING WITH UP TO AN INCH
OF NEW SNOW POSSIBLE.
SNOW DIMINISHES THIS EVENING BUT FLURRIES ARE POSSIBLE ACROSS THE
CWA AS WE SHOULD HAVE SOME SATURATION IN THE DGZ AND FORCING FROM
THE APPROACHING TROUGH/S VORT STREAMERS. THE UPPER LEVEL TROUGH
MOVES OVERHEAD MONDAY AND ITS ASSOCIATED SURFACE LOW PASSES OVER
LAKE SUPERIOR EARLY MONDAY MORNING. GUIDANCE FEATURES SATURATION IN
THE DGZ SO HAVE FLURRIES IN FOR AREAS SOUTH OF I-88. AREAS NORTH OF
I-88 MAY SEE LIGHT SNOW AND CURRENTLY ONLY HAVE A SLIGHT CHANCE OF
SNOW. CONFIDENCE IS LOW IN MEASURABLE SNOW OCCURRING MONDAY. GUSTY
WEST WINDS MOVE IN BEHIND THE COLD FRONT AS WELL WITH GUSTS UP TO 30
MPH.
TEMPS REMAIN BELOW NORMAL WITH HIGHS TODAY IN THE LOW TO MID
30S...BUT TEMPERATURES WILL BE MUCH COLDER MONDAY. LOWS SUNDAY NIGHT
WILL BE IN THE TEENS TO AROUND 20 OVER NW INDIANA...AND MIN WIND
CHILLS WILL BE IN THE SINGLE DIGITS. A FEW OUTLYING AREAS MAY EVEN
SEE WIND CHILLS DIP BELOW ZERO. HIGHS ON MONDAY WILL ONLY BE IN THE
LOW 30S WITH WIND CHILLS IN THE SINGLE DIGITS TO AROUND ZERO.
JEE
&&
.LONG TERM...
256 AM CST
MONDAY NIGHT THROUGH MONDAY...
GUIDANCE CONTINUES TO HAVE THE BULK OF ARCTIC AIR MOVE OVER THE CWA
MONDAY NIGHT...AND LOWERED LOW TEMPS TO THE LOW TEENS DOWNTOWN TO
THE SINGLE DIGITS IN OUTLYING AREAS. GUSTY WEST WINDS PERSIST
OVERNIGHT WITH GUSTS AROUND 25 MPH. THIS WILL RESULT IN VERY COLD
WIND CHILLS EARLY TUESDAY MORNING. LOOKING AT 0 TO -10F DOWNTOWN AND
SOME OUTLYING AREAS WILL BE IN THE -10 TO -15F RANGE.
THE GOOD NEWS IS THE TROUGH SHIFTS EAST TUESDAY WITH HIGHS IN THE
20S AND LIGHTER SOUTHWEST WINDS. WITH UPPER LEVEL VORT STREAMERS
STILL MOVING OVERHEAD...KEPT FLURRIES IN THE FORECAST FOR MOST OF
THE CWA...AND A CHANCE OF LAKE EFFECT SNOW OVER PORTER COUNTY.
A SURFACE LOW PASSES OVER NORTHERN WI LATE TUESDAY NIGHT INTO
WEDNESDAY MORNING WITH ITS COLD FRONT MOVING THROUGH DURING THE DAY.
COULD SEE LIGHT SNOW ALONG THE IL/WI STATE LINE EARLY WEDNESDAY
MORNING AND THEN A SLIGHT CHANCE OF SNOW FOR MOST OF THE CWA DURING
THE DAY. HAVE LOW CONFIDENCE IN ORGANIZED ACCUMULATING SNOW SINCE
GUIDANCE DIFFERS ON HOW FAR NORTH THE LOW WILL BE. THINKING THE
BETTER FORCING FOR SNOW WILL BE ASSOCIATED WITH THE LOW. WEDNESDAY
DOES LOOK SLIGHTLY WARMER WITH HIGHS IN THE LOW 30S.
THE UPPER LEVEL PATTERN DIFFERS GREATLY AMONG GUIDANCE MEMBERS FOR
THE END OF THIS WEEK WITH THE GFS SHOWING A FASTER PROGRESSION. IN
GENERAL AN UPPER LEVEL TROUGH MOVES THROUGH BRINGING ANOTHER ROUND
OF COLD AIR AND A FEW SLIGHT CHANCES OF SNOW. A WARM UP IS STILL IN
STORE LATE THIS WEEK WITH TEMPS ABOVE FREEZING. THIS COULD LEAD TO A
RAIN/SNOW EVENT BUT IT/S MUCH TOO FAR OUT TO MENTION SPECIFICS NOW.
JEE
&&
.CLIMATE...
RECORD TO NEAR-RECORD COLD IS POSSIBLE EARLY NEXT WEEK. HERE ARE
THE CURRENT RECORD TEMPERATURES AT BOTH CHICAGO AND ROCKFORD FOR
MONDAY AND TUESDAY.
...CHICAGO...
RECORD COLDEST HIGH TEMPERATURE:
TUESDAY THE 18TH...22 IN 1903.
RECORD LOW TEMPERATURE:
TUESDAY THE 18TH...8 IN 1880.
WEDNESDAY THE 19TH...10 IN 1894.
...ROCKFORD...
RECORD COLDEST HIGH TEMPERATURE:
TUESDAY THE 18TH...28 IN 1951.
RECORD LOW TEMPERATURE:
TUESDAY THE 18TH...11 IN 1989.
WEDNESDAY THE 19TH...7 IN 1914.
KJB/MTF/IZZI
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* SNOW WITH IFR VSBYS THROUGH 20Z
* ADDITIONAL LIGHT SNOW/FLURRIES THIS AFTERNOON WITH POTENTIAL FOR
MVFR VSBYS.
* MVFR CIGS THIS AFTERNOON AND EVENING.
* GUSTY WEST WINDS MONDAY
KMD
//DISCUSSION...UPDATED 18Z...
ORGANIZED LIGHT SNOW BAND WILL PUSH SOUTHEAST OF THE CHICAGOLAND
TERMINALS IN THE COMING HOURS...CLEARING ORD BY 19Z AND MDW BY
20Z. IN THE MAIN BAND IFBR VSBYS WILL CONTINUE...WHICH IS LARGELY
NORTH OF INTERSTATE 80...WITH MVFR VSBYS FARTHER SOUTH.
ACCUMULATIONS SHOULD MAINLY BE ON GRASSY SURFACES AS THE SNOW IS
RATHER DRY. BACK BEHIND THIS BAND ADDITIONAL LIGHT SNOW SHOWERS
WILL CONTINUE THROUGH THE EARLY EVENING HOURS WITH MVFR VSBYS AT
TIMES. MEANWHILE...CIGS ARE EXPECTED TO REMAIN MVFR THROUGH THE
AFTERNOON...THOUGH IT IS NOT CLEAR HOW LOW THEY WILL BE IN THE
MVFR CATEGORY AS SOME IMPROVEMENT IS POSSIBLE AS THE DAY GOES ON.
A STRONG COLD FRONT APPROACHES FROM THE WEST THIS EVENING WITH
IMPROVEMENT TO VFR BEHIND THE LEADING EDGE OF THIS FRONT WHICH IS
EXPECTED AT KRFD AROUND 3Z AND THEN IN CHICAGOLAND BY 5Z OR SO.
THE REAL SURGE OF COLD AIR COMES MONDAY MORNING WHICH WILL BRING
GUSTY WEST WINDS INTO THE TERMINALS FOR MUCH OF THE DAY ALONG WITH
AT LEAST OCCASIONAL MVFR CIGS.
KMD
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* MEDIUM-HIGH IN LGT SNOW TIMING AND VIS IMPACTS WITH IFR LARGELY
CONFINED TO THE NEXT FEW HOURS
* MEDIUM-HIGH IN MVFR CIGS...THOUGH MEDIUM ON IF THEY WILL
INCREASE ABOVE 2000 FT THIS AFTERNOON.
* HIGH CONFIDENCE IN WIND TRENDS
KMD
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
MONDAY NIGHT...MVFR CIGS/FLURRIES LIKELY. -SHSN POSSIBLE.
TUESDAY...CHANCE OF MVFR CIGS/FLURRIES.
WEDNESDAY...CHANCE OF MVFR CIGS AND SHSN.
THURSDAY THROUGH SATURDAY...PRIMARILY VFR.
RATZER
&&
.MARINE...
230 AM CST
GALE WATCH WILL BE ISSUED FOR LAKE MICHIGAN OPEN WATERS FROM MID-
AFTERNOON MONDAY THROUGH MID-DAY TUESDAY.
MAIN MARINE CONCERN THIS MORNING IS WITH DEVELOPMENT OF GUSTY
WESTERLY WINDS MONDAY THROUGH TUESDAY IN THE WAKE OF A STRONG COLD
FRONT AND DEEPENING LOW PRESSURE WHICH WILL MOVE FROM THE NORTHERN
LAKES EAST AND THEN NORTHEAST ACROSS QUEBEC AND LABRADOR THROUGH
MID-WEEK. TIGHTENING OF THE SURFACE PRESSURE GRADIENT BETWEEN THIS
DEEPENING LOW AND STRONG HIGH PRESSURE BUILDING SOUTHEAST THROUGH
THE PLAINS WILL COMBINE WITH STEEP LOW LEVEL LAPSE RATES OVER THE
LAKE TO PRODUCE WESTERLY GALE FORCE WINDS FROM MONDAY AFTERNOON
THROUGH TUESDAY MORNING. ANOTHER LOW WILL MOVE ACROSS THE NORTHERN
LAKES WEDNESDAY...WITH THE POTENTIAL FOR ANOTHER PERIOD OF GALES
WEDNESDAY AND WEDNESDAY NIGHT. NOT UNTIL LATE IN THE WEEK DOES IT
LOOK LIKE WINDS WILL DIMINISH SIGNIFICANTLY...WITH VARIOUS FORECAST
MODELS EVENTUALLY DEVELOPING HIGH PRESSURE ACROSS THE MIDWEST
FRIDAY.
ILLINOIS/INDIANA NEARSHORE WATERS WILL NEED SMALL CRAFT ADVISORY BY
MID-DAY MONDAY...AND THOUGH HAVE ELECTED TO LEAVE NEARSHORE WATERS
OUT OF THE GALE WATCH IN COLLABORATION WITH NEIGHBORING WFOS AT THIS
TIME...ITS POSSIBLE SCA COULD NEED TO BE UPGRADED TO GALE WARNING.
RATZER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...GALE WATCH...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...3 PM MONDAY TO NOON
TUESDAY.
&&
$$
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
1157 AM CST Sun Nov 16 2014
.UPDATE...
ISSUED AT 1037 AM CST SUN NOV 16 2014
Forecast overall looks on track and just a few adjustments needed
today. Will maintain the winter weather advisory from 3 pm through
tonight across southeast third of CWA. Have 1-2 inches of snow se
of a Taylorville to Decatur to Champaign line to near I-70 this
afternoon/evening and 2-3 inches of snow from I-70 southeast with
highest amounts near the Wabash river. Just a dusting to less than
half inch of snow north of I-72 today. Highs similar to yesterday
in the mid to upper 30s with mildest readings in southeast IL with
Lawrenceville reaching near 40F. SW winds 5-10 mph today and become
WSW this evening as cold front over eastern IA/MO moves east
across IL during this evening. Widespread snow will develop across
se third of CWA during this afternoon and then diminish behind the
cold front later this evening and overnight. Wind will become WNW
later tonight and Monday morning and increase to 15 to 25 mph
ushering in colder air and causing some blowing snow.
&&
.SHORT TERM...(Today)
ISSUED AT 341 AM CST SUN NOV 16 2014
High pressure sliding off to the east over the Atlantic Seaboard
this morning as a lull in the pressure gradient moves into the
region. Though the sfc pattern is weak, an upper level disturbance
from the desert SW is moving out and across the region today, with
the best chances for snow showers later this afternoon/evening and
into the overnight hours. Weak winds today becoming increasingly
southwesterly ahead of the advancing showers. A larger trof over
the region and backing into the Plains, still associated with some
light snow showers and flurries also making its way across the
region and the Great Lakes. Have some pops in today for the areas
along and north of a line from Havana to Bloomington, mainly during
the first half of the day. The next wave moving into the middle of
the state by mid day from the SW. Latest 00z model runs in the
SREF, the NAM, the GFS, the GEM, the ECMWF...all shifting a bit
further north with the snow accumulation. Models focusing just
north of I-70 corridor between 21z and 00z with the heaviest of the
snowfall, spreading southward and then slowly shifting southward
with the chances for more snowfall beyond 00z. Snowfall totals
close to 2 to 3 inches along and south of a line from Edgar to
Shelbyville...just barely reaching advisory criteria...but with the
first snow of the season, it being somewhat early for the SE, and
the chance for this to make a messy commute early on Monday, have
gone ahead with the headline at this time. Concern with the axis of
the early qpf shifting northward, that another row of counties may
be needed on the north side...but not nearly enough consistency in
the model runs to be comfortable with that. Borderline 1 to 2
inches in counties north of the advisory to a line from Springfield
to Champaign, but being some of the early accumulations, certainly
potential to make a mess.
&&
.LONG TERM...(Tonight through Saturday)
ISSUED AT 341 AM CST SUN NOV 16 2014
Cold in the forecast not letting up. Several shots of cP air dipping
into the region from the north. Cyclonic flow aloft and plenty of
cold air lending to flurries for Monday afternoon. Temperatures on
the back side of that take a significant dive as 850 mb temps drop
into the -7C to -18C range by Monday afternoon. Early Tuesday
morning will be incredibly cold with lows forecast for single digits
and low 10s F. Winds will be up that morning, resulting in wind
chills dipping into the negative single digits before noon...and not
climbing above the single digits through the afternoon.
Temperatures begin to moderate with a more southerly fetch to the
sfc winds on Tues night/Wed, though still well below seasonal norms.
Minor warm again into the weekend...but still below normal and in
advance of yet another potentially snowy weekend. Next chance for
precip was prev on Thursday but now the GFS and ECMWF are starting
to have major conflicts in the passage of the upper trof from Thurs
to Sat...and the forecast blend is masking some of the more radical
differences. Keeping the pop mentions to a minimum and running more
in line with the drier ECMWF for now, as opposed to a more
aggressive GFS. Best chances for precip associated with the wave
after that going into the weekend.
&&
.AVIATION...(For the 18Z TAFS through 18Z Monday afternoon)
ISSUED AT 1155 AM CST SUN NOV 16 2014
Scattered light snow and flurries early this afternoon with MVFR
ceilings 1-3k ft and vsbys 3-5 miles at times with light fog/haze
as well. A more widespread shield of light snow will develop from
the sw during mid afternoon into early evening and affect areas
mainly se of I-55 with lowest vsbys of 1-3 miles at DEC and CMI
from 21Z-01Z and possible IFR ceilings. A cold front near the
IA/IL border into southeast MO will move east acorss central IL
this evening. Light snow will diminish to scattered flurries
behind the cold front during tonight and Monday morning and low
clouds may scatter out for a time, but MVFR clouds return during
Monday morning as next short wave trof settles in. SW winds 5-9
this afternoon to shift west this evening and then WNW around 10
kts overnight and increase to 10-15 kts with gusts 18-25 kts Monday
morning.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY from 3 PM this afternoon to 6 AM CST
Monday FOR ILZ054>057-061>063-066>068-071>073.
&&
$$
UPDATE...07
SHORT TERM...HJS
LONG TERM...HJS
AVIATION...07
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
1045 AM CST Sun Nov 16 2014
.UPDATE...
ISSUED AT 1037 AM CST SUN NOV 16 2014
Forecast overall looks on track and just a few adjustments needed
today. Will maintain the winter weather advisory from 3 pm through
tonight across southeast third of CWA. Have 1-2 inches of snow se
of a Taylorville to Decatur to Champaign line to near I-70 this
afternoon/evening and 2-3 inches of snow from I-70 southeast with
highest amounts near the Wabash river. Just a dusting to less than
half inch of snow north of I-72 today. Highs similar to yesterday
in the mid to upper 30s with mildest readings in southeast IL with
Lawrenceville reaching near 40F. SW winds 5-10 mph today and become
WSW this evening as cold front over eastern IA/MO moves east
across IL during this evening. Widespread snow will develop across
se third of CWA during this afternoon and then diminish behind the
cold front later this evening and overnight. Wind will become WNW
later tonight and Monday morning and increase to 15 to 25 mph
ushering in colder air and causing some blowing snow.
&&
.SHORT TERM...(Today)
ISSUED AT 341 AM CST SUN NOV 16 2014
High pressure sliding off to the east over the Atlantic Seaboard
this morning as a lull in the pressure gradient moves into the
region. Though the sfc pattern is weak, an upper level disturbance
from the desert SW is moving out and across the region today, with
the best chances for snow showers later this afternoon/evening and
into the overnight hours. Weak winds today becoming increasingly
southwesterly ahead of the advancing showers. A larger trof over
the region and backing into the Plains, still associated with some
light snow showers and flurries also making its way across the
region and the Great Lakes. Have some pops in today for the areas
along and north of a line from Havana to Bloomington, mainly during
the first half of the day. The next wave moving into the middle of
the state by mid day from the SW. Latest 00z model runs in the
SREF, the NAM, the GFS, the GEM, the ECMWF...all shifting a bit
further north with the snow accumulation. Models focusing just
north of I-70 corridor between 21z and 00z with the heaviest of the
snowfall, spreading southward and then slowly shifting southward
with the chances for more snowfall beyond 00z. Snowfall totals
close to 2 to 3 inches along and south of a line from Edgar to
Shelbyville...just barely reaching advisory criteria...but with the
first snow of the season, it being somewhat early for the SE, and
the chance for this to make a messy commute early on Monday, have
gone ahead with the headline at this time. Concern with the axis of
the early qpf shifting northward, that another row of counties may
be needed on the north side...but not nearly enough consistency in
the model runs to be comfortable with that. Borderline 1 to 2
inches in counties north of the advisory to a line from Springfield
to Champaign, but being some of the early accumulations, certainly
potential to make a mess.
&&
.LONG TERM...(Tonight through Saturday)
ISSUED AT 341 AM CST SUN NOV 16 2014
Cold in the forecast not letting up. Several shots of cP air dipping
into the region from the north. Cyclonic flow aloft and plenty of
cold air lending to flurries for Monday afternoon. Temperatures on
the back side of that take a significant dive as 850 mb temps drop
into the -7C to -18C range by Monday afternoon. Early Tuesday
morning will be incredibly cold with lows forecast for single digits
and low 10s F. Winds will be up that morning, resulting in wind
chills dipping into the negative single digits before noon...and not
climbing above the single digits through the afternoon.
Temperatures begin to moderate with a more southerly fetch to the
sfc winds on Tues night/Wed, though still well below seasonal norms.
Minor warm again into the weekend...but still below normal and in
advance of yet another potentially snowy weekend. Next chance for
precip was prev on Thursday but now the GFS and ECMWF are starting
to have major conflicts in the passage of the upper trof from Thurs
to Sat...and the forecast blend is masking some of the more radical
differences. Keeping the pop mentions to a minimum and running more
in line with the drier ECMWF for now, as opposed to a more
aggressive GFS. Best chances for precip associated with the wave
after that going into the weekend.
&&
.AVIATION...(For the 12Z TAFS through 12Z Monday morning)
ISSUED AT 520 AM CST SUN NOV 16 2014
Variable cigs and vsbys across the forecast area this morning with
forecast soundings and the latest HRRR suggesting lower cigs will
hold over most of the area thru the afternoon hours as a weather
system pushes to the south of the TAF sites. This will bring
some scattered areas of light snow this morning with a steadier
snowfall developing along and south of a SPI to CMI line with MVFR
and local IFR cigs and vsbys in snow. Further north, mainly MVFR
with a tempo IFR group in this morning with some flurries and most
of the steadier snows staying just south of BMI. Models suggest
the system producing the snow will shift south and east this
evening with a gradual improving trend seen at PIA to VFR conditions
after 05z. Surface winds once again today will not be much of a
factor with south to southwest winds around 10 kts, with winds
becoming westerly tonight with a gradual increase in speeds to 10
to 15 kts in the 05z-08z time frame.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY from 3 PM this afternoon to 6 AM CST
Monday FOR ILZ054>057-061>063-066>068-071>073.
&&
$$
UPDATE...07
SHORT TERM...HJS
LONG TERM...HJS
AVIATION...Smith
AREA FORECAST DISCUSSION
NWS NEW ORLEANS LA
1250 PM CST SUN NOV 16 2014
.SOUNDING DISCUSSION...
18Z SOUNDING MORE UNSTABLE THAN THE 12Z FLIGHT AS EXPECTED.
PW WENT FROM 1.12 TO 1.47 INCHES. LI DOWN TO -0.5 WITH THE
0 TO 3 KM RELATIVE HELICITY INCREASED TO 402 MSQ/SSQ.
IMPRESSIVE LOW LEVEL JET WITH 40KT AT 1800FT. WINDS ARE
MIXING TO THE GROUND AND ALREADY GUSTING TO 32KT AT KMSY
AND 27KT AT KBTR. THIS WILL CONTINUE TO SPREAD NORTH TO
THE NORTHSHORE AND SW MS AHEAD OF THIS LINE OF STORMS. THE
TAKEAWAY IS WE ARE MORE UNSTABLE WITH THUNDERSTORMS THIS
AFTERNOON. THERE IS A SLIGHT RISK OF SEVERE WEATHER PER SPC
AND WELL SUPPORTED BY THE 18Z SOUNDING. THE MAIN THREAT WILL
BE STRONG GUSTY WINDS OVER 60MPH AND A SLIGHT CHANCE OF
TORNADOES WITH THE STRONGER THUNDERSTORMS. STAY TUNED FOR
ANY WATCHES AND WARNINGS THIS AFTERNOON. KEG
&&
.PREV DISCUSSION... /ISSUED 1012 AM CST SUN NOV 16 2014/
UPDATE...
SHOWERS AND THUNDERSTORMS ARE ONGOING JUST OFF TO THE WEST OF THE
FORECAST AREA. HAVE UPDATED THE FORECAST TO SHOW THE INCREASE IN
TEMPERATURES AND DEWPOINTS. THE STORM PREDICTION CENTER STILL
MAINTAINS A SLIGHT RISK FOR SEVERE WEATHER OVER OUR FORECAST AREA.
THE LATEST HRRR SUGGEST THAT THE BULK OF THE THUNDERSTORMS SHOULD
START MOVING INTO THE AREA AFTER NOON IN THE WESTERN PORTIONS OF
THE FORECAST AREA. WE WILL HAVE TO WATCH STORM DEVELOPMENT THIS
AFTERNOON AS THE ATMOSPHERE IS BECOMING MORE UNSTABLE AHEAD OF THE
FRONT. THIS WILL ONLY ADD TO CONVECTIVE STRENGTH LATER THIS
AFTERNOON. 13/MH
PREV DISCUSSION... /ISSUED 732 AM CST SUN NOV 16 2014/
SOUNDING DISCUSSION...
MUCH DIFFERENT LOOKING SOUNDING THAN THIS TIME YESTERDAY. SOUTHERLY
FLOW MEASURED FROM THE SFC TO 6800FT THEN SSW FLOW THROUGH MUCH OF
THE ATMO. MOISTURE EVIDENT FROM THE SFC TO 10500FEET WITH A DRY
LATER ABOVE THROUGH 33KFT WHERE SOME UPPER LEVEL MOISTURE WAS
MEASURED. PW UP TO 1.12 INCHES WITH THIS SOUNDING. SEVERE PARAMETERS
NOT THERE YET...HOWEVER THIS SNAP SHOT OF THE ATMO WILL MODIFY THROUGH
THE DAY AND BECOME RIPE FOR SOME THUNDERSTORMS WITH A SLIGHT CHANCE
OF SEVERE WEATHER.
PREV DISCUSSION... /ISSUED 420 AM CST SUN NOV 16 2014/
SYNOPSIS...
LATEST SURFACE ANALYSIS SHOWED AN INVERTED TROUGH FROM TEXAS COAST
TO CENTRAL MISSISSIPPI AND A LOW OVER CENTRAL TEXAS. PRECIPITABLE
WATER PLOTS ON A PLANER VIEW REVEALED A SURGE OF MOISTURE WITH
VALUES AROUND 1.25 INCHES ALONG THE CENTRAL TEXAS COAST AT 00Z.
SURFACE DEWPOINT READINGS RANGE FROM THE UPPER 40S ACROSS SOUTH
MISSISSIPPI TO THE MID 50S ALONG THE LOUISIANA COAST. MANY POINTS
HAVE SEEN THEIR MORNING LOWS AND TEMPS CONTINUE TO RISE BEFORE
SUNSET. UPPER AIR ANALYSIS SHOWED A SOUTHWESTERLY FLOW OVER THE
SOUTHERN TIER CONUS AND A POSITIVELY TILTED TROUGH FROM THE
MINNESOTA TO THE GREAT BASIN. ISOTACH ANALYSIS AT 250MB SHOWED A
JET MAX AROUND 140 KNOTS ON THE BACK SIDE OF THE WAVE...FROM
NORTHERN CALIFORNIA TO NORTHERN NEW MEXICO. WATER VAPOR IMAGERY
SHOWED DARKENING OR VIGOROUS DISTURBANCE ASSOCIATED WITH THE JET
MAX OVER SOUTHERN NEVADA AND ANOTHER DISTURBANCE OVER WESTERN
MONTANA. REGIONAL RADARS CONTINUE TO SHOW AN INCREASE IN COVERAGE
OF SHOWERS FROM NORTH MISSISSIPPI TO NORTH LOUISIANA TO SOUTHEAST
TEXAS.
DISCUSSION...
SURFACE INVERTED TROUGH WILL SLOWLY EVOLVE INTO A LOW OVER
SOUTHWEST MISSISSIPPI/CENTRAL LOUISIANA. SURFACE DEWPOINT WILL
INCREASE INTO THE 60S AND POOL ALONG TO THE TROUGH AXIS TODAY AND
PLACING MOST OF THE FORECAST AREA IN THE WARM SECTOR. SURFACE
WINDS WILL BECOME SOUTHERLY TODAY. THE APPROACHING UPPER LEVEL
TROUGH WILL MAINTAIN A SOUTHWEST FLOW OF 50 TO 60 KNOTS 500 TO
200MB OVER FORECAST AREA. VEERING WINDS WINDS TODAY SHOW INCREASE
OF LL HELICITY VALUES 300 TO 500 M/S ACROSS THE NORTH HALF OF
FORECAST AREA...ACCORDING TO GFS. HOWEVER...MEANINGFUL CAPE VALUES
RANGE FROM 100 TO 700J/KG ACROSS SOUTH MISSISSIPPI AND EAST
CENTRAL LOUISIANA THIS AFTERNOON THROUGH THIS EVENING. AT THE SAME
TIME...PW VALUES WILL POOL ALONG THE FRONTAL BOUNDARY AND AHEAD OF
THE MAIN TROUGH WITH VALUES UP TO 1.75 INCHES. WIDESPREAD SHOWERS
AND EMBEDDED TS WILL DEVELOP OVER THE NORTHWEST ZONES THIS
AFTERNOON AND SLOW MOVE EAST THIS EVENING AND OVERNIGHT. AS A
RESULT...WILL MAINTAIN CATEGORICAL RAIN CHANCES WITH THIS SYSTEM
PRODUCING PRODUCING 1 TO 2 INCREASE ACROSS THE FORECAST AREA THIS
AFTERNOON AND TONIGHT. MANY AREAS ARE EXTREMELY DRY AND SHOULD
HANDLE THE HEAVY RAINFALL.
EXPECTING THE TROUGH TO PUSH THE MOISTURE THROUGH BY MONDAY
MORNING. THE SECOND SURGE ASSOCIATED WITH THE DISTURBANCE UP NORTH WILL
ARRIVE MONDAY AND SCOUR OUR THE REMAINING MOISTURE AND CLOUD
COVER. STRONG COLD AIR ADVECTION WILL ALLOW TEMPS DIVE AGAIN AND
POSSIBLY PUSH PARTS OF SOUTHWEST MISSISSIPPI TO A HARD FREEZE
TUESDAY AND SOUTH SHORE TO A NEAR FREEZE. SOME MODERATION WILL
OCCUR BY THURSDAY FOLLOWED BY ANOTHER SYSTEM BRINGING A CHANCE OF
RAIN FRIDAY AND NEXT WEEKEND. INSTABILITY MAY LAG TIL SATURDAY SO
WILL THUNDER UNTIL THE WEEKEND.
AVIATION...
CONDITIONS WILL GRADUALLY DETERIORATE TODAY AS A COLD FRONT
APPROACHES THE AREA. MVFR CIGS ARE EXPECTED TO SET IN DURING THE
LATE MORNING OR EARLY AFTERNOON. SHOWERS AND THUNDERSTORMS WILL MOVE
INTO THE AREA THIS AFTERNOON AND WILL REMAIN IN THE AREA THROUGH
TONIGHT. WINDS WILL BE ELEVATED OUT OF THE SOUTH TODAY AND WILL
SHIFT TO THE NORTHWEST LATE TONIGHT BEHIND THE COLD FRONT.
MARINE...
A LOW PRESSURE SYSTEM WILL MOVE THROUGH THE AREA THIS AFTERNOON AND
TONIGHT. INCREASED ONSHORE FLOW WILL DEVELOP IN ADVANCE OF THIS
LOW...AND EXERCISE CAUTION HEADLINES HAVE BEEN HOISTED FOR ALL
COASTAL WATERS TODAY WITH SMALL CRAFT ADVISORIES TAKING EFFECT
TONIGHT. A STRONG FRONTAL BOUNDARY WILL SHIFT WINDS TO THE NORTHWEST
AND NORTH ON MONDAY AND WILL STRENGTHEN INTO THE 25 TO 30 KNOT
RANGE. FREQUENT STRONGER GUSTS MAY STILL NECESSITATE A GALE WATCH OR
WARNING OVER THE OPEN GULF WATERS...ESPECIALLY MONDAY NIGHT. THE
PRESSURE GRADIENT WILL BEGIN TO RELAX ON TUESDAY WITH CONDITIONS
GRADUALLY IMPROVING AS HIGH PRESSURE SETTLES OVER THE AREA.
DECISION SUPPORT...
DSS CODE...BLUE.
DEPLOYED...NONE.
ACTIVATION...NONE.
ACTIVITIES...SLURRY SUPPORT.
MONITORING POTENTIAL FOR ISOLATED SEVERE WEATHER THIS
AFTERNOON THROUGH TONIGHT.
DECISION SUPPORT SERVICES (DSS) CODE LEGEND
GREEN = NO WEATHER IMPACTS THAT REQUIRE ACTION
BLUE = LONG FUSED WATCH/WARNING/ADVISORY IN EFFECT OR HIGH
VISIBILITY EVENT
YELLOW = HEIGHTENED IMPACTS WITH SHORT FUSED
WATCH/WARNING/ADVISORY ISSUANCES; RADAR SUPPORT
ORANGE = HIGH IMPACTS - SLIGHT TO MODERATE RISK SEVERE; NEARBY
TROPICAL EVENTS; HAZMAT OR OTHER LARGE EPISODES
RED = FULL ENGAGEMENT FOR MODERATE TO HIGH RISK SVR
AND/OR DIRECT TROPICAL THREATS; EVENTS OF NATIONAL
SIGNIFICANCE.
&&
.PRELIMINARY POINT TEMPS/POPS...
MCB 40 47 23 44 / 100 30 10 0
BTR 40 49 23 47 / 100 30 10 0
ASD 45 52 25 47 / 100 40 10 0
MSY 47 51 32 47 / 100 40 10 0
GPT 48 53 27 47 / 100 40 10 0
PQL 50 54 26 47 / 100 40 10 0
&&
.LIX WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
GM...SMALL CRAFT ADVISORY FROM MIDNIGHT MONDAY TO 6 PM TUESDAY FOR
THE FOLLOWING ZONES: COASTAL WATERS FROM BOOTHVILLE LA TO
THE SOUTHWEST PASS OF THE MISSISSIPPI RIVER OUT 20
NM...COASTAL WATERS FROM PASCAGOULA MS TO STAKE ISLAND LA
FROM 20 TO 60 NM...COASTAL WATERS FROM PASCAGOULA MS TO
STAKE ISLAND LA OUT 20 NM...COASTAL WATERS FROM PORT
FOURCHON TO LOWER ATCHAFALAYA RIVER FROM 20 TO 60
NM...COASTAL WATERS FROM PORT FOURCHON TO LOWER ATCHAFALAYA
RIVER OUT 20 NM...COASTAL WATERS FROM STAKE ISLAND LA TO
THE SOUTHWEST PASS OF THE MISSISSIPPI RIVER FROM 20 TO 60
NM...COASTAL WATERS FROM THE SOUTHWEST PASS OF THE
MISSISSIPPI RIVER TO PORT FOURCHON FROM 20 TO 60 NM...AND
COASTAL WATERS FROM THE SOUTHWEST PASS OF THE MISSISSIPPI
RIVER TO PORT FOURCHON OUT 20 NM.
SMALL CRAFT ADVISORY FROM 6 AM MONDAY TO 6 AM TUESDAY FOR THE
FOLLOWING ZONES: BRETON SOUND...CHANDELEUR SOUND...LAKE
BORGNE...LAKE PONTCHARTRAIN AND LAKE MAUREPAS...AND
MISSISSIPPI SOUND.
MS...NONE.
GM...SMALL CRAFT ADVISORY FROM 6 AM MONDAY TO 6 AM TUESDAY FOR THE
FOLLOWING ZONES: BRETON SOUND...CHANDELEUR SOUND...LAKE
BORGNE...LAKE PONTCHARTRAIN AND LAKE MAUREPAS...AND
MISSISSIPPI SOUND.
SMALL CRAFT ADVISORY FROM MIDNIGHT MONDAY TO 6 PM TUESDAY FOR
THE FOLLOWING ZONES: COASTAL WATERS FROM BOOTHVILLE LA TO
THE SOUTHWEST PASS OF THE MISSISSIPPI RIVER OUT 20
NM...COASTAL WATERS FROM PASCAGOULA MS TO STAKE ISLAND LA
FROM 20 TO 60 NM...COASTAL WATERS FROM PASCAGOULA MS TO
STAKE ISLAND LA OUT 20 NM...COASTAL WATERS FROM PORT
FOURCHON TO LOWER ATCHAFALAYA RIVER FROM 20 TO 60
NM...COASTAL WATERS FROM PORT FOURCHON TO LOWER ATCHAFALAYA
RIVER OUT 20 NM...COASTAL WATERS FROM STAKE ISLAND LA TO
THE SOUTHWEST PASS OF THE MISSISSIPPI RIVER FROM 20 TO 60
NM...COASTAL WATERS FROM THE SOUTHWEST PASS OF THE
MISSISSIPPI RIVER TO PORT FOURCHON FROM 20 TO 60 NM...AND
COASTAL WATERS FROM THE SOUTHWEST PASS OF THE MISSISSIPPI
RIVER TO PORT FOURCHON OUT 20 NM.
&&
$$
AREA FORECAST DISCUSSION
NWS NEW ORLEANS LA
1012 AM CST SUN NOV 16 2014
.UPDATE...
SHOWERS AND THUNDERSTORMS ARE ONGOING JUST OFF TO THE WEST OF THE
FORECAST AREA. HAVE UPDATED THE FORECAST TO SHOW THE INCREASE IN
TEMPERATURES AND DEWPOINTS. THE STORM PREDICTION CENTER STILL
MAINTAINS A SLIGHT RISK FOR SEVERE WEATHER OVER OUR FORECAST AREA.
THE LATEST HRRR SUGGEST THAT THE BULK OF THE THUNDERSTORMS SHOULD
START MOVING INTO THE AREA AFTER NOON IN THE WESTERN PORTIONS OF
THE FORECAST AREA. WE WILL HAVE TO WATCH STORM DEVELOPMENT THIS
AFTERNOON AS THE ATMOSPHERE IS BECOMING MORE UNSTABLE AHEAD OF THE
FRONT. THIS WILL ONLY ADD TO CONVECTIVE STRENGTH LATER THIS
AFTERNOON. 13/MH
&&
.PREV DISCUSSION... /ISSUED 732 AM CST SUN NOV 16 2014/
SOUNDING DISCUSSION...
MUCH DIFFERENT LOOKING SOUNDING THAN THIS TIME YESTERDAY. SOUTHERLY
FLOW MEASURED FROM THE SFC TO 6800FT THEN SSW FLOW THROUGH MUCH OF
THE ATMO. MOISTURE EVIDENT FROM THE SFC TO 10500FEET WITH A DRY
LATER ABOVE THROUGH 33KFT WHERE SOME UPPER LEVEL MOISTURE WAS
MEASURED. PW UP TO 1.12 INCHES WITH THIS SOUNDING. SEVERE PARAMETERS
NOT THERE YET...HOWEVER THIS SNAP SHOT OF THE ATMO WILL MODIFY THROUGH
THE DAY AND BECOME RIPE FOR SOME THUNDERSTORMS WITH A SLIGHT CHANCE
OF SEVERE WEATHER.
PREV DISCUSSION... /ISSUED 420 AM CST SUN NOV 16 2014/
SYNOPSIS...
LATEST SURFACE ANALYSIS SHOWED AN INVERTED TROUGH FROM TEXAS COAST
TO CENTRAL MISSISSIPPI AND A LOW OVER CENTRAL TEXAS. PRECIPITABLE
WATER PLOTS ON A PLANER VIEW REVEALED A SURGE OF MOISTURE WITH
VALUES AROUND 1.25 INCHES ALONG THE CENTRAL TEXAS COAST AT 00Z.
SURFACE DEWPOINT READINGS RANGE FROM THE UPPER 40S ACROSS SOUTH
MISSISSIPPI TO THE MID 50S ALONG THE LOUISIANA COAST. MANY POINTS
HAVE SEEN THEIR MORNING LOWS AND TEMPS CONTINUE TO RISE BEFORE
SUNSET. UPPER AIR ANALYSIS SHOWED A SOUTHWESTERLY FLOW OVER THE
SOUTHERN TIER CONUS AND A POSITIVELY TILTED TROUGH FROM THE
MINNESOTA TO THE GREAT BASIN. ISOTACH ANALYSIS AT 250MB SHOWED A
JET MAX AROUND 140 KNOTS ON THE BACK SIDE OF THE WAVE...FROM
NORTHERN CALIFORNIA TO NORTHERN NEW MEXICO. WATER VAPOR IMAGERY
SHOWED DARKENING OR VIGOROUS DISTURBANCE ASSOCIATED WITH THE JET
MAX OVER SOUTHERN NEVADA AND ANOTHER DISTURBANCE OVER WESTERN
MONTANA. REGIONAL RADARS CONTINUE TO SHOW AN INCREASE IN COVERAGE
OF SHOWERS FROM NORTH MISSISSIPPI TO NORTH LOUISIANA TO SOUTHEAST
TEXAS.
DISCUSSION...
SURFACE INVERTED TROUGH WILL SLOWLY EVOLVE INTO A LOW OVER
SOUTHWEST MISSISSIPPI/CENTRAL LOUISIANA. SURFACE DEWPOINT WILL
INCREASE INTO THE 60S AND POOL ALONG TO THE TROUGH AXIS TODAY AND
PLACING MOST OF THE FORECAST AREA IN THE WARM SECTOR. SURFACE
WINDS WILL BECOME SOUTHERLY TODAY. THE APPROACHING UPPER LEVEL
TROUGH WILL MAINTAIN A SOUTHWEST FLOW OF 50 TO 60 KNOTS 500 TO
200MB OVER FORECAST AREA. VEERING WINDS WINDS TODAY SHOW INCREASE
OF LL HELICITY VALUES 300 TO 500 M/S ACROSS THE NORTH HALF OF
FORECAST AREA...ACCORDING TO GFS. HOWEVER...MEANINGFUL CAPE VALUES
RANGE FROM 100 TO 700J/KG ACROSS SOUTH MISSISSIPPI AND EAST
CENTRAL LOUISIANA THIS AFTERNOON THROUGH THIS EVENING. AT THE SAME
TIME...PW VALUES WILL POOL ALONG THE FRONTAL BOUNDARY AND AHEAD OF
THE MAIN TROUGH WITH VALUES UP TO 1.75 INCHES. WIDESPREAD SHOWERS
AND EMBEDDED TS WILL DEVELOP OVER THE NORTHWEST ZONES THIS
AFTERNOON AND SLOW MOVE EAST THIS EVENING AND OVERNIGHT. AS A
RESULT...WILL MAINTAIN CATEGORICAL RAIN CHANCES WITH THIS SYSTEM
PRODUCING PRODUCING 1 TO 2 INCREASE ACROSS THE FORECAST AREA THIS
AFTERNOON AND TONIGHT. MANY AREAS ARE EXTREMELY DRY AND SHOULD
HANDLE THE HEAVY RAINFALL.
EXPECTING THE TROUGH TO PUSH THE MOISTURE THROUGH BY MONDAY
MORNING. THE SECOND SURGE ASSOCIATED WITH THE DISTURBANCE UP NORTH WILL
ARRIVE MONDAY AND SCOUR OUR THE REMAINING MOISTURE AND CLOUD
COVER. STRONG COLD AIR ADVECTION WILL ALLOW TEMPS DIVE AGAIN AND
POSSIBLY PUSH PARTS OF SOUTHWEST MISSISSIPPI TO A HARD FREEZE
TUESDAY AND SOUTH SHORE TO A NEAR FREEZE. SOME MODERATION WILL
OCCUR BY THURSDAY FOLLOWED BY ANOTHER SYSTEM BRINGING A CHANCE OF
RAIN FRIDAY AND NEXT WEEKEND. INSTABILITY MAY LAG TIL SATURDAY SO
WILL THUNDER UNTIL THE WEEKEND.
AVIATION...
CONDITIONS WILL GRADUALLY DETERIORATE TODAY AS A COLD FRONT
APPROACHES THE AREA. MVFR CIGS ARE EXPECTED TO SET IN DURING THE
LATE MORNING OR EARLY AFTERNOON. SHOWERS AND THUNDERSTORMS WILL MOVE
INTO THE AREA THIS AFTERNOON AND WILL REMAIN IN THE AREA THROUGH
TONIGHT. WINDS WILL BE ELEVATED OUT OF THE SOUTH TODAY AND WILL
SHIFT TO THE NORTHWEST LATE TONIGHT BEHIND THE COLD FRONT.
MARINE...
A LOW PRESSURE SYSTEM WILL MOVE THROUGH THE AREA THIS AFTERNOON AND
TONIGHT. INCREASED ONSHORE FLOW WILL DEVELOP IN ADVANCE OF THIS
LOW...AND EXERCISE CAUTION HEADLINES HAVE BEEN HOISTED FOR ALL
COASTAL WATERS TODAY WITH SMALL CRAFT ADVISORIES TAKING EFFECT
TONIGHT. A STRONG FRONTAL BOUNDARY WILL SHIFT WINDS TO THE NORTHWEST
AND NORTH ON MONDAY AND WILL STRENGTHEN INTO THE 25 TO 30 KNOT
RANGE. FREQUENT STRONGER GUSTS MAY STILL NECESSITATE A GALE WATCH OR
WARNING OVER THE OPEN GULF WATERS...ESPECIALLY MONDAY NIGHT. THE
PRESSURE GRADIENT WILL BEGIN TO RELAX ON TUESDAY WITH CONDITIONS
GRADUALLY IMPROVING AS HIGH PRESSURE SETTLES OVER THE AREA.
DECISION SUPPORT...
DSS CODE...BLUE.
DEPLOYED...NONE.
ACTIVATION...NONE.
ACTIVITIES...SLURRY SUPPORT.
MONITORING POTENTIAL FOR ISOLATED SEVERE WEATHER THIS
AFTERNOON THROUGH TONIGHT.
DECISION SUPPORT SERVICES (DSS) CODE LEGEND
GREEN = NO WEATHER IMPACTS THAT REQUIRE ACTION
BLUE = LONG FUSED WATCH/WARNING/ADVISORY IN EFFECT OR HIGH
VISIBILITY EVENT
YELLOW = HEIGHTENED IMPACTS WITH SHORT FUSED
WATCH/WARNING/ADVISORY ISSUANCES; RADAR SUPPORT
ORANGE = HIGH IMPACTS - SLIGHT TO MODERATE RISK SEVERE; NEARBY
TROPICAL EVENTS; HAZMAT OR OTHER LARGE EPISODES
RED = FULL ENGAGEMENT FOR MODERATE TO HIGH RISK SVR
AND/OR DIRECT TROPICAL THREATS; EVENTS OF NATIONAL
SIGNIFICANCE.
&&
.PRELIMINARY POINT TEMPS/POPS...
MCB 73 42 49 23 / 100 100 30 10
BTR 77 42 50 24 / 100 100 30 10
ASD 76 48 53 27 / 90 100 40 10
MSY 77 48 51 32 / 90 100 40 10
GPT 71 51 54 28 / 90 100 40 10
PQL 72 54 56 27 / 90 100 40 10
&&
.LIX WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
GM...SMALL CRAFT ADVISORY FROM MIDNIGHT MONDAY TO 6 PM TUESDAY FOR
THE FOLLOWING ZONES: COASTAL WATERS FROM BOOTHVILLE LA TO
THE SOUTHWEST PASS OF THE MISSISSIPPI RIVER OUT 20
NM...COASTAL WATERS FROM PASCAGOULA MS TO STAKE ISLAND LA
FROM 20 TO 60 NM...COASTAL WATERS FROM PASCAGOULA MS TO
STAKE ISLAND LA OUT 20 NM...COASTAL WATERS FROM PORT
FOURCHON TO LOWER ATCHAFALAYA RIVER FROM 20 TO 60
NM...COASTAL WATERS FROM PORT FOURCHON TO LOWER ATCHAFALAYA
RIVER OUT 20 NM...COASTAL WATERS FROM STAKE ISLAND LA TO
THE SOUTHWEST PASS OF THE MISSISSIPPI RIVER FROM 20 TO 60
NM...COASTAL WATERS FROM THE SOUTHWEST PASS OF THE
MISSISSIPPI RIVER TO PORT FOURCHON FROM 20 TO 60 NM...AND
COASTAL WATERS FROM THE SOUTHWEST PASS OF THE MISSISSIPPI
RIVER TO PORT FOURCHON OUT 20 NM.
SMALL CRAFT ADVISORY FROM 6 AM MONDAY TO 6 AM TUESDAY FOR THE
FOLLOWING ZONES: BRETON SOUND...CHANDELEUR SOUND...LAKE
BORGNE...LAKE PONTCHARTRAIN AND LAKE MAUREPAS...AND
MISSISSIPPI SOUND.
MS...NONE.
GM...SMALL CRAFT ADVISORY FROM 6 AM MONDAY TO 6 AM TUESDAY FOR THE
FOLLOWING ZONES: BRETON SOUND...CHANDELEUR SOUND...LAKE
BORGNE...LAKE PONTCHARTRAIN AND LAKE MAUREPAS...AND
MISSISSIPPI SOUND.
SMALL CRAFT ADVISORY FROM MIDNIGHT MONDAY TO 6 PM TUESDAY FOR
THE FOLLOWING ZONES: COASTAL WATERS FROM BOOTHVILLE LA TO
THE SOUTHWEST PASS OF THE MISSISSIPPI RIVER OUT 20
NM...COASTAL WATERS FROM PASCAGOULA MS TO STAKE ISLAND LA
FROM 20 TO 60 NM...COASTAL WATERS FROM PASCAGOULA MS TO
STAKE ISLAND LA OUT 20 NM...COASTAL WATERS FROM PORT
FOURCHON TO LOWER ATCHAFALAYA RIVER FROM 20 TO 60
NM...COASTAL WATERS FROM PORT FOURCHON TO LOWER ATCHAFALAYA
RIVER OUT 20 NM...COASTAL WATERS FROM STAKE ISLAND LA TO
THE SOUTHWEST PASS OF THE MISSISSIPPI RIVER FROM 20 TO 60
NM...COASTAL WATERS FROM THE SOUTHWEST PASS OF THE
MISSISSIPPI RIVER TO PORT FOURCHON FROM 20 TO 60 NM...AND
COASTAL WATERS FROM THE SOUTHWEST PASS OF THE MISSISSIPPI
RIVER TO PORT FOURCHON OUT 20 NM.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1105 AM EST SUN NOV 16 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 420 AM EST SUN NOV 16 2014
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS AN ARCTIC BRANCH UPR
TROF CENTERED OVER HUDSON BAY DOWNSTREAM OF A RDG OVER WRN CANADA. A
SHRTWV MOVING E THRU MN IS EMBEDDED IN THE POLAR BRANCH WLY FLOW
DOMINATING THE CONUS AND BRINGING AN AREA OF LIGHT SN TO THE E HALF
OF MN...MUCH OF WI AND SCENTRAL UPR MI EARLY THIS MRNG. ALTHOUGH
THERE IS FAIRLY STRONG DPVA/DEEP LYR QVECTOR CNVGC AND SOME UPR DVGC
CONTRIBUTING TO DEEP MOISTENING ALOFT AND FORCING THIS AREA OF SN...
ONLY WEAK LLVL MSTR INFLOW THAT IS LIMITING PWAT TO NO MORE THAN
ABOUT 0.33 INCH AT GRB /85 PCT OF NORMAL/ AND H7 SPECIFIC HUMIDITY
TO NO MORE THAN ABOUT 1 G/KG IS LIMITING THE OVERALL SN INTENSITY.
SINCE H85 TEMPS ARE ABOUT -14C...THE LLVL WSW FLOW IS BRINGING SOME
LES TO THE KEWEENAW. BUT RATHER DRY NATURE OF THE LLVL AIR IN NRN MN
AS DEPICTED ON THE 00Z INL RAOB APPEARS TO BE LIMITING THE INTENSITY
OF THIS SN. LOOKING FARTHER UPSTREAM IN SCENTRAL CANADA...A VERY
STRONG SHRTWV EMBEDDED IN THE NW ARCTIC BRANCH FLOW IS DIGGING SEWD
NEAR LK WINNIPEG.
MAIN FCST CONCERNS IN THE SHORT TERM ARE SN TRENDS/AMOUNTS OVER
MAINLY THE SE HALF OF THE CWA ASSOCIATED WITH DISTURBANCE THAT WL BE
MOVING THRU WI. FOCUS FOR LATER TNGT SHIFTS TO POTENTIAL FOR MORE SN
OVER MAINLY THE W IN ADVANCE OF SHRTWV NOW NEAR LK WINNIPEG.
TODAY...THE SHRTWV IN MN EARLY THIS MRNG IS PROGGED TO MOVE STEADILY
ENEWD INTO NRN LOWER MI BY 18Z AND THEN INTO SE ONTARIO DURING THE
AFTN. AREA OF DPVA/DEEP LYR QVECTOR CNVGC/UPR DVGC IS FCST TO IMPACT
THE SE CWA THIS MRNG BEFORE EXITING BY 18Z AND GIVING WAY TO SOME
FAIRLY VIGOROUS DNVA/DEEP LYR QVECTOR DVGC. SINCE THE UPR FLOW IS
TENDING TO BACK MORE IN ADVANCE OF THE DIGGING SHRTWV IN SCENTRAL
CANADA AND MODEL TRENDS SHOW THE DYNAMIC FORCING SHIFTED FARTHER TO
THE N AND RADAR TRENDS/SFC OBS INDICATE THE SN AREA IS MOVING
FARTHER TO THE N...INCRSD POPS OVER AREA S OF A LINE FM ABOUT
IRONWOOD TO MARQUETTE. BUT MODEL QPF IS ONLY A COUPLE HUNDREDTHS OF
AN INCH...SO ANY SN ACCUM WL BE ON THE LIGHT SIDE WITH LIMITED
ABSOLUTE MSTR AND POOR SN GROWTH GIVEN ELEVATED AREA OF FORCING WELL
ABOVE LOWER DGZ. THE LARGER SCALE PCPN WL END BY 18Z FOLLOWING THE
EXIT OF THE DYNAMIC SUPPORT. SINCE THE LLVL FLOW IS FCST TO BACK
SLOWLY BUT STEADILY THRU THE DAY IN ADVANCE OF SHRTWV DIGGING SEWD
TOWARD NW MN...EXPECT THE LES OVER THE KEWEENAW EARLY THIS MRNG TO
SHIFT OUT INTO LK SUP. FOR THE MOST PART...THE HIER RES MODELS
INDICATE THE LLVL FLOW WL NOT BACK ENUF TO BRING MUCH IF ANY LES INTO
LUCE/SCHOOLCRAFT COUNTIES TODAY. BUT WL MAINTAIN SOME CHC POPS OVER
THE SE PORTIONS OF THESE COUNTIES LATE TO REFLECT UNCERTAINTY.
OTRW...DESPITE THE MID LVL DRYING/SUBSIDENCE...THE BACKING LLVL FLOW
WL ALLOW SOME LO CLDS IN WI TO MOVE INTO UPR MI...LIMITING THE
POTENTIAL FOR MORE SUNSHINE. THE BEST CHANCE FOR MORE SUNSHINE WL BE
NEAR LK SUP...WHERE THE LLVL SW FLOW WL DOWNSLOPE.
TNGT...AS THE SHRTWV TO THE NW DIGS SEWD TOWARD NW LK SUP AND CLOSES
OFF BY 12Z MON...BAND OF DEEP LYR QVECTOR CNVGC IN THE MSTR STARVED
COMMA TAIL OF THIS FEATURE IS FCST TO SWING ACROSS UPR MI. ONCE
AGAIN...AN ABSENCE OF SGFNT LLVL MOISTENING WL BE AN IMPEDIMENT TO
WIDESPREAD LIGHT SN. THE BEST CHC FOR MORE WIDESPREAD SN WL BE LATE
OVER THE W...WHERE THE COLD FNT/ENHANCED LLVL CNVGC ASSOCIATED WITH
THE SHRTWV WL ARRIVE LATE. ALSO MAINTAINED SOMEWHAT HIER POPS TO THE
E OF MANISTIQUE-NEWBERRY TO ACCOUNT FOR THE POTENTIAL OF SOME LES
OFF LK MI AS THE INCOMING DYNAMICS COINCIDE WITH A LLVL FLOW BACKED
SUFFICIENTLY TO THE SSW FOR SOME LK EFFECT ESPECIALLY IN THE EVNG.
ONCE THIS COMMA TAIL RIBBON OF FORCING PASSES TO THE E LATE...THE
WINDS MAY VEER ENUF TO DIMINISH THIS POTENTIAL OVER THE E.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 349 AM EST SUN NOV 16 2014
A LOW CURRENTLY TO THE NORTHEAST OF LAKE WINNIPEG WILL DROP
SOUTHEAST OVER LAKE SUPERIOR TONIGHT AND BE THE KEY FEATURE IN
BRINGING ANOTHER SHOT OF COLD AIR ALONG WITH A PERIOD OF LAKE EFFECT
SNOW TO THE AREA FOR MONDAY AND TUESDAY.
THERE WILL LIKELY BE A FEW LIGHT SNOW SHOWERS OVER THE WESTERN U.P.
IN ASSOCIATION WITH THE LOW MOVING THROUGH THE AREA AND JUST AHEAD
OF THE SURFACE TROUGH OVER WESTERN LAKE SUPERIOR AND STARTING TO
COME ONSHORE AT 12Z. AS THIS THIS PUSHES THROUGH...WINDS WILL SHIFT
AROUND TO THE NORTHWEST AND LEAD TO STEADILY INCREASING LAKE EFFECT
(DELTA-T VALUES ABOVE 20) OVER THE WESTERN CWA DURING THE MORNING.
DEEP MOISTURE ASSOCIATED WITH THE LOW WILL REALLY SURGE INTO THE
AREA MONDAY AFTERNOON AND REMAIN THROUGH MONDAY NIGHT OVER THE WEST
AND TUESDAY MORNING OVER THE EAST. THE COOLING ALOFT AND DEEP
MOISTURE WILL ALLOW FOR THE LAKE EFFECT SNOW SHOWERS TO UTILIZE THE
LAKE INDUCED EQUILIBRIUM LEVELS IN THE 15-17KFT RANGE. THUS...WOULD
EXPECT THE LAKE EFFECT TO REALLY INCREASE IN THE AFTERNOON OVER THE
WEST HALF. WITH PLENTY OF UPWARD MOTION (LAKE INDUCED CAPE VALUES OF
700-800 J/KG) AND THE PREVIOUSLY MENTIONED MOISTURE/EQL VALUES
SHOULD SUPPORT MODERATE TO HEAVY LAKE EFFECT SNOW. PLUS...WITH A
GOOD PORTION OF THE LOW LEVEL FORCING RIGHT IN THE DGZ...WOULD
EXPECT THE SNOW RATIOS TO BE IN THE LOW-MID 20S (HELD DOWN SOME FROM
THE TRADITIONALLY HIGHER VALUES DUE TO THE STRENGTH OF THE WINDS).
THE FAVORABLE PERIOD OF LAKE EFFECT WILL CONTINUE INTO THE EVENING
AND LEAD TO SNOWFALL AMOUNTS THE SNOWBELTS OVER THE WEST IN THE 5
TO 11 INCH RANGE BY MIDNIGHT MONDAY NIGHT. EXPECT THE SNOW TO
DIMINISH HEADING INTO THE OVERNIGHT HOURS AS THE DEEPER MOISTURE
DEPARTS...BUT STILL SHOULD SEE LIGHT TO MODERATE SNOWFALL INTO
TUESDAY MORNING WITH SNOW RATIOS HELPED BY WEAKER WINDS AND ALL OF
THE CLOUD BEING IN THE DGZ.
THE STRONG LAKE EFFECT/ENHANCED SNOW SHOWERS WILL SHIFT EAST THROUGH
THE AFTERNOON/EVENING INTO NORTH CENTRAL AND EVENTUALLY EASTERN
UPPER MICHIGAN BEHIND THE SURFACE TROUGH. 00Z RUNS LOOK TO HAVE SPED
UP THE ARRIVAL OF THE CONVERGENT BAND OF LAKE ENHANCED SNOW OVER THE
NORTH CENTRAL AND HAVE FOLLOWED THAT IDEA FOR POPS/SNOWFALL MONDAY
NIGHT. MARQUETTE COUNTY WILL BE INTERESTING SINCE THE WIND PROFILE
WOULD SUPPORT NORTH WIND LES AT 850MB AND NORTH-NORTHWEST IN THE
LOWER LEVELS ON MONDAY EVENING BEFORE TRANSITIONING TO GENERALLY
NORTHWEST LAKE EFFECT BY TUESDAY MORNING. THAT NNW WIND DIRECTION
WOULD SUPPORT THE BANDS GINNING INTO THE HIGHER TERRAIN AREAS AND
AIDING SNOWFALL TOTALS. THE CYCLONIC FLOW BEHIND THE LOW WILL
TRANSITION THE LES INTO WESTERN ALGER COUNTY AND WITH COASTAL
CONVERGENCE ALONG THE MARQUETTE COUNTY SHORELINE...WOULD EXPECT
HEAVY LAKE EFFECT SNOW THERE AFTER MIDNIGHT MONDAY NIGHT AND
CONTINUING THROUGH AT LEAST TUESDAY MORNING. THE STRENGTH OF THE
WINDS SHOULD CARRY THE LAKE EFFECT WELL INLAND OVER EAST-CENTRAL
UPPER MICHIGAN...WITH AT LEAST A FEW INCHES OF ACCUMULATION POSSIBLE
IN EASTERN DELTA AND SOUTHWEST SCHOOLCRAFT COUNTIES. FOR MARQUETTE
AND WESTERN ALGER COUNTIES...EXPECT 24HR SNOWFALL TOTALS (MONDAY
AFTERNOON THROUGH TUESDAY MORNING) IN THE 5 TO 11 INCH RANGE
ALSO...WITH THE HIGHEST VALUES OVER THE HURON MOUNTAINS AND WESTERN
ALGER COUNTY. WHILE CONDITIONS BECOME LESS FAVORABLE ON TUESDAY WITH
INVERSION HEIGHTS LOWERING AHEAD OF THE UPPER RIDGE...THE LAKE
FORCING WILL REMAIN IN THE DGZ AND ENABLE THE POTENTIAL FOR SOME
VERY FLUFFY ACCUMULATION AS WINDS BACK TO THE WEST AND EVENTUALLY
SOUTHWEST.
SO HOW TO HANDLE THE POTENTIAL HEADLINES. WILL ISSUE A LAKE
EFFECT SNOW WATCH FOR GOGEBIC/ONTONAGON...NRN. HOUGHTON AND
KEWEENAW COUNTY DUE TO THE EXPECTED IMPACTS MONDAY INTO MONDAY
NIGHT. ALTHOUGH SNOWFALL AMOUNTS WILL LIKELY BE MORE IN THE
ADVISORY RANGE OVER THE KEWEENAW...THOUGHT THE WIND GUSTS IN THE
35-40MPH RANGE WOULD CREATE ENOUGH BLOWING SNOW TO INCLUDE THEM IN
THE WATCH. GOGEBIC/ONTONAGON WILL SEE SLIGHTLY LOWER WINDS BUT A
BETTER OPPORTUNITY TO SEE WARNING SNOWFALL. AS FOR FARTHER
EAST...THINGS GET A LITTLE MORE COMPLICATED. THINK BARAGA/MARQUETTE
ARE SOLID LES ADVISORIES...BUT BELIEVE WESTERN ALGER COUNTY WILL
SEE WARNING SNOWFALL ON MONDAY NIGHT. DEBATED ISSUING A WATCH FOR
ALGER...ESPECIALLY WITH THE ADDED WIND FACTOR...BUT WAS CONCERNED
THERE WOULD BE ASSUMPTIONS MADE THAT MARQUETTE/BARAGA WOULDN/T
EXPERIENCE ANY IMPACTS SINCE THEY WEREN/T IN A WATCH (EVEN THOUGH
THEY WOULD SUPPORT HAVING AN ADVISORY). THEREFORE...HAVE LEFT OUT
FOR NOW...WHICH WILL ALLOW THE DAY SHIFT TO CONVERT THE WATCH OVER
THE WEST TO WARNING/ADVISORY AND START THE ADVISORY TRANSITION TO
THE EAST FOR SOME OF THE OTHER COUNTIES. AT THAT POINT A WATCH
COULD BE ISSUED.
THE UPPER TROUGH DRIVING THIS PERIOD OF COLD AND LAKE EFFECT WILL
SHIFT TO THE EAST ON TUESDAY AFTERNOON/NIGHT...ALLOWING A WEAK HIGH
PRESSURE RIDGE TO BUILD OVER THE AREA FOR TUESDAY NIGHT.
THUS...WOULD EXPECT THE LAKE EFFECT TO TRANSITION TO THE WESTERLY
OR EVEN SOUTHWESTERLY WIND FAVORED LOCATIONS (KEWEENAW AND ALONG THE
LAKE SUPERIOR SHORELINE EAST OF GRAND MARAIS) AS WINDS BACK. ANOTHER
SHORTWAVE DIVING SOUTHEAST THROUGH CENTRAL CANADA ON TUESDAY WILL
DROP INTO THE UPPER GREAT LAKES REGION LATE TUESDAY NIGHT...BRINGING
ANOTHER SURFACE TROUGH THROUGH THE REGION AND USHERING IN COLD AIR
AND LAKE EFFECT FOR WEDNESDAY INTO THURSDAY. WILL LIKELY SEE SOME
SYNOPTIC SNOWFALL WITH THIS SHORTWAVE...BUT GENERALLY A DUSTING TO
AN INCH OF SNOW NEAR THE WISCONSIN BORDER. BEHIND THIS
TROUGH...EXPECT LAKE EFFECT TO OCCUR IN THE WEST-NORTHWEST FAVORED
LOCATIONS. THERE ARE SOME HINTS OF A LINGERING SURFACE TROUGH
DROPPING SOUTHEAST ACROSS EASTERN LAKE SUPERIOR LATE WEDNESDAY
NIGHT...WHICH WOULD SWITCH WINDS TO MORE OF A NORTHWEST OR
NORTH-NORTHWEST DIRECTION OVER THE EAST. OVERALL...LOOKS LIKE LAKE
EFFECT PARAMETERS ON WEDNESDAY NIGHT AND THURSDAY WILL BE SIMILAR TO
THE BEGINNING OF THE WORK WEEK AND LEAD TO THE POTENTIAL FOR ANOTHER
MODERATE-HEAVY LAKE EFFECT SNOW NEAR LAKE SUPERIOR. WILL CONTINUE
TO MENTION THIS PERIOD IN THE HWO/EHWO.
FRIDAY AND SATURDAY...THE UPPER TROUGH AFFECTING THE AREA
WEDNESDAY/THURSDAY WILL SHIFT EAST AND OUT OF THE AREA ON FRIDAY.
THIS WILL LEAD TO TEMPERATURES TRYING TO WARM TOWARDS NORMAL AS A
WEAK UPPER RIDGE MOVES OVER THE AREA. A SURFACE HIGH WILL BRUSH THE
AREA ON FRIDAY KEEPING LAKE EFFECT CONFINED TO THE WESTERLY WIND
LOCATIONS. THERE ARE HINTS IN SOME OF THE MODELS OF A WEAK
DISTURBANCE AFFECTING THE AREA ON FRIDAY NIGHT INTO SATURDAY...BUT
CONFIDENCE IS LOW AT THIS TIME.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1104 AM EST SUN NOV 16 2014
EXPECT TEMPORARY IMPROVEMENTS TO THE CEILINGS/VIS THIS
AFTERNOON...BEFORE THE MAIN TROUGH OVER W ONTARIO AND MN THIS
AFTERNOON SWEEPS OVER UPPER MI THIS EVENING THROUGH MONDAY MORNING.
THE MAIN IMPACT AVIATION WISE WILL LIKELY HOLD OFF UNTIL AFTER AT
LEAST 04Z MONDAY...AFTER THAT THE MAIN TROUGH WILL TURN OUR SW WINDS
BACK TO THE NW. THIS SHOULD BRING A SIGNIFICANT BAND OF SNOW TO IWD
AND CMX...INTENSIFYING AFTER 09Z AND CONTINUING THROUGH THE REST OF
MONDAY WITH MAINLY MID TO LOW END MVFR CEILINGS. WINTER WEATHER
HEADLINES REMAIN POSTED FOR IWD AND CMX AREAS FROM AROUND DAYBREAK
MONDAY ON. LOOK FOR WINDS TO INCREASE DURING THE DAYTIME HOURS
MONDAY...WITH GUSTS OF 20-25KTS AT IWD FROM 12-18Z MONDAY. THESE
STRONGER WINDS SHOULD GET TO CMX AS WELL...BUT MAY BE A COUPLE HOURS
SLOWER. BLOWING SNOW COULD HELP REDUCE VIS TO IFR.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 349 AM EST SUN NOV 16 2014
SOUTHWEST WINDS UP TO 30KTS WILL CONTINUE TODAY AHEAD OF A LOW
PRESSURE SYSTEM JUST TO THE EAST OF LAKE WINNIPEG. THIS SYSTEM WILL
DROP SOUTHEAST AND OVER LAKE SUPERIOR TONIGHT AND THEN SLOWLY EXIT
TO THE EAST ON MONDAY. AS A TROUGH ASSOCIATED WITH THE LOW SWEEPS
ACROSS THE LAKE ON MONDAY...COLD AIR SURGING ACROSS THE RELATIVELY
WARM WATERS OF LAKE SUPERIOR WILL LEAD TO THE POTENTIAL FOR
NORTHWEST GALE FORCE WINDS OF 35 TO 40KTS MONDAY AFTERNOON INTO
TUESDAY MORNING OVER MUCH OF LAKE SUPERIOR. WILL ISSUE A GALE
WATCH TO ACCOUNT FOR THE EXPECTED GALES...SPREADING FROM WEST TO
EAST MONDAY AFTERNOON/EVENING. WINDS WILL GRADUALLY DECREASE TUESDAY
AFTERNOON INTO TUESDAY NIGHT AS A WEAK HIGH PRESSURE RIDGE MOVES
ACROSS THE AREA. ANOTHER TROUGH WILL SWEEP SOUTHEAST ACROSS THE
UPPER GREAT LAKES REGION WEDNESDAY MORNING AND BRING AN INCREASE IN
WINDS OUT OF THE NORTHWEST (UP TO 30KTS) WHICH WILL CONTINUE INTO
THURSDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW WATCH FROM MONDAY MORNING THROUGH TUESDAY
MORNING FOR MIZ001>003-009.
LAKE SUPERIOR...
GALE WATCH FROM LATE MONDAY NIGHT THROUGH TUESDAY AFTERNOON FOR
LSZ267.
GALE WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY AFTERNOON FOR
LSZ265-266.
GALE WATCH FROM MONDAY AFTERNOON THROUGH LATE MONDAY NIGHT FOR
LSZ162.
GALE WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY MORNING FOR
LSZ242>245-263-264.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...SRF
AVIATION...KF
MARINE...SRF
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
348 PM CST Sun Nov 16 2014
.SHORT TERM: (Through Late Tonight)
Issued at 345 PM CST Sun Nov 16 2014
Snow is clearing from the west to east this afternoon, and latest
short-range guidance shows that it should continue to push east at a
decent clip through early evening. RAP and HRRR have done a very
good job with this system (as they did with yesterday`s
precipitation) so am following them closely. The surface cold front
which currently looks to be along a line from near Pittsfield to
near the Lake of the Ozarks, will push slowly eastward tonight.
While accumulating snow should end across most of the area by
00-02Z, some flurries could linger along and east of the Mississippi
from St. Louis southward until the cold front finally pushes through
bringing drier low level air to the area. An additional 1-2 inches
of snow with locally higher amounts is still possible until the
snow ends...primarily on elevated surfaces. Based on current obs
and latest radar trends, will be dropping the advisory west and
north of the STL area, while continuing the advisory into the
early evening hours over southeast sections of the CWA.
Guidance appears to have a reasonable handle on overnight lows.
Leading edge of the first round of Arciic air (as defined by
single digits dewpoints) currently entering northwest sections of
the CWA, and this will be followed by a secondary surge of Arctic
air (now working into the mid-Missouri Valley) that will enter the
CWA during the predawn hours. In this situation guidance has a tendency
to be a bit too cool due to mixing and some clouds, but due to the
shear strength of cold air in this situation believe "thinking
cold" is the way to go.
Carney/Truett
.LONG TERM: (Monday through Next Sunday)
Issued at 313 PM CST Sun Nov 16 2014
Monday-Wednesday
Deep and unseasonably strong UA trof over the eastern half of the
CONUS will mean more unseasonably cold November temperatures in
our area through midweek. Obviously, temperature specifics are
going to be the main forecast problem in the short term, and going
forecasts appear to have a fairly good handle on the expected
trends.
Secondary surge of Arctic air that enters the FA late tonight
will be a much colder airmass than any we`ve experienced during
this early taste of winter, and there is good agreement in the 12z
synoptic runs that 850mb temps of -18 to -20C will be common over
the mid-Mississippi Valley by Monday evening. Low level RH progs
suggest quite a bit of low level cloudiness overspreading the area
on Monday in the wake of the secondary cold front, and this cloud
cover combined with the very cold airmass will almost certainy
mean highs only in the 20s for most of the CWA. Perhaps the
biggest question is Monday night. While airmass is extremely cold
for this time of year and there may be snow on the ground in some
locations over the southeast half of the CWA, the center of the
Arctic high is forecast to drop from the Plains into the Arklatex
region. The resultant pressure gradient in our area should mean
that westerly winds will persist throughout much of the night,
with this mixing keeping low temps from reaching record levels.
Normally in this situation would be worried about climo bias
causing guidance to be too warm, but due to the aforementioned
winds and mixing believe it may have a good handle on Monday
night temp trends at this point in time. See climate section for
more info on record lows/record low max temps for the next few
days/nights.
AMS moderation will begin on Tuesday as the center of the Arctic
high works its way in the the se U.S., with additional warming on
Wednesday due to warm advection ahead of next shortwave.
Precipitation threat over the next few days should be limited to a
few flurries with the arrival of the cold air and low clouds
tomorrow.
Thursday-Sunday
Another shot of cold air will settle into the region in the wake of
Wednesday`s shortwave. However, this next round of cold air will
not be nearly as strong as the Artic airmass that invades the region
tomorrow and tomorrow night, and as a result it`s impact on late
week temps will not be nearly as dramatic.
Temperatures will moderate heading into next weekend as trof axis
works east and allows a more zonal flow regime to develop over the
nation`s heartland. Resultant low level warm advection/isentropic
ascent, combined with an approach of an upper level trof in the
southern branch of the westerlies, should mean a chance of
precipitation. Last several medium range runs, as well as latest
12z guidance, suggests ams will warm enough that the bulk of this
precip will be in liquid form.
Truett
&&
.AVIATION: (For the 18z TAFs through 18z Monday Afternoon)
Issued at 1156 AM CST Sun Nov 16 2014
Upper level disturbance moving over the area at this time is
producing light to moderate snow with widespread vsbys between
3-5SM and areas of vsbys at or below 2SM generally along and east
of a line from KCOU to KPPQ. Snowfall intensity and lower end IFR
conditions will increase this afternoon as the disturbance moves
through, and additional lift is provided by and advancing surface
cold front. Snow will end behind the cold front as drier air works
its way into the area. Low end MVFR ceilings will likely trail
the cold front by a few hours before scattering out late this
evening/overnight as the dry air deepens. Expect gusty northwest
flow and VFR conditions on Monday as high pressure builds across
the Great Plains.
Specifics for KSTL:
Generally expect MVFR flight conditions early this afternoon with
increasing snowfall intensity leading to IFR conditions by mid-
afternoon. Moderate to occasionally heavy snow is possible for a
brief period ahead of an approaching cold front as it interacts
with an upper level disturbance. Preferred not to include vsbys
below 1SM as there is still some uncertainty this will occur.
Should see conditions improve by 00Z-01Z time frame as the front
passes through. Low end MVFR cigs will likely linger behind the
front until drier air deepens enough to scatter them out late this
evening or overnight. Expect gusty northwest flow and VFR
conditions on Monday as high pressure builds across the Great
Plains.
Carney
&&
.CLIMATE:
The following are record low maximums and record low minimums for
each of the next 4 days, which corresponds to the expected length
of the current cold spell and record snowfall for St. Louis and
Columbia for Saturday and Sunday when the area is expecting the
first widespread accumulating snowfall of the season.
Date: 11/16 11/17 11/18
St. Louis
Low High: 29/1997 17/1880 25/1880
Low: 13/1959 6/1959 14/1932
Snowfall: 0.1/1997 1.0/1951
Columbia
Low High: 30/1932 23/1959 27/1903
Low: 8/1959 4/1959 8/1891
Snowfall: 4.8/1932 0.1/1989
Quincy
Low High: 28/1997 19/1959 24/1903
Low: 4/1959 3/1959 7/1903
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...WINTER WEATHER ADVISORY until 9 PM CST this evening FOR Iron MO-
Madison MO-Reynolds MO-St. Francois MO-Ste. Genevieve MO.
WINTER WEATHER ADVISORY until 6 PM CST this evening FOR
Jefferson MO-St. Louis City MO-St. Louis MO.
IL...WINTER WEATHER ADVISORY until 9 PM CST this evening FOR Bond IL-
Clinton IL-Fayette IL-Madison IL-Marion IL-Monroe IL-
Randolph IL-St. Clair IL-Washington IL.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1216 PM CST Sun Nov 16 2014
.UPDATE:
Issued at 916 AM CST Sun Nov 16 2014
RAP and HRRR models seem to be handling this morning`s snow pretty
well. RAP especially...with a very nice depiction of the moderate
snow band over central/west central Missouri in the omega fields.
The initial band looks to be weakening over our area, but over the
next couple of hours, the 500MB omega ramps back up again late
this morning/early this afternoon over central MO up into east
central. This combined with good low to mid level frontogenesis
should produce another round of moderate and possibly heavy snow
for a couple of hours. Have therefore expanded the advisory
slightly...mainly to keep a consistent message with accumulations
of 1-2 inches through this afternoon.
Carney
&&
.SHORT TERM: (Through Late This Afternoon)
Issued at 355 AM CST Sun Nov 16 2014
The main weather focus through tonight will be yet another quick
hitting minor winter storm system...where is it going...timing...
and how much snow.
The main culprit for today`s weather will be a upper level TROF axis
extending from the upper MS valley to the central High Plains. Add
to the resultant broadscale lift region out ahead of it a
strengthening h300 130kt jet streak and h850-700 frontogenesis and
the ingredients are there for a more organized and broader reaching
accumulating snow event.
Radar shows this already coming together over parts of northwest MO
with snow being reported in the Kansas City area. Models are
anticipating this initial area of snow to weaken as it moves east
into our region, but this will merely be temporary, with the main
brunt...currently over southern KS...to push east-northeastward and
affect our region from late morning thru the afternoon and into
early evening.
The models have done quite a bit of adjusting the past 24-48hrs,
with a decent shift northward with where to track the pcpn, and
based on current obs, this seems well in hand. Frontogenesis will
be the main driver of where the best snow intensities will setup,
and there is excellent consensus on this being over an area along
and south of a line from roughly 30mi north of the I-44 corridor in
MO and 30mi north of the I-70 corridor in IL. Much of the
accumulating snow will fall during the afternoon, but areas in MO
will see the accumulating snow already by late morning while areas
in IL will continue to see some minor additional accums into the
early evening. The forcing will be further enhanced by a
backbuilding h300 jet, especially over southeast MO and southern IL.
With thick clouds in place already, virtually no advection, and
increasing pcpn coverage, temps will struggle to rise much from
where they are now. This fully supports the cooler MAV MOS temps
and have went with for the forecast. This in turn will result in a
snowier pcpn-type forecast than originally anticipated. Have
trimmed the mixed pcpn coverage to just southeast MO and a small
part of southern IL where some sleet and rain will be possible early
in the event...changing to snow during.
Putting it all together, look for a broad area of 1-2" snowfall
amounts along and south of a line from just north of the I-44
corridor in MO and just north of the I-70 corridor in IL. Will
hoist a winter wx advisory for this area. Little to snow accums
expected elsewhere although nearly all locations should see at least
some light snow.
TES
.LONG TERM: (Tonight through Saturday)
Issued at 355 AM CST Sun Nov 16 2014
A longwave upper level TROF will dig and expand into the eastern and
central CONUS on Monday before gradually shifting east and gradually
losing its hold over our region during the week. Look for another
shot of unseasonable cold on Monday and Tuesday with some recovery
towards average for mid to late week, although with the overall
upper pattern the way it is, it will be tough to actually get back
to normal temps.
Have maintained flurries mention for Monday with deep cyclonic flow
and upper level disturbances rotating down.
Another disturbance will move thru Wednesday accompanied by another
cold front, but at this time, it looks to be going thru dry.
Something to watch.
A more significant system for next weekend will affect our area late
Saturday or just beyond into next Sunday. A much warmer atmosphere
by this time should keep the pcpn all liquid.
TES
&&
.AVIATION: (For the 18z TAFs through 18z Monday Afternoon)
Issued at 1156 AM CST Sun Nov 16 2014
Upper level disturbance moving over the area at this time is
producing light to moderate snow with widespread vsbys between
3-5SM and areas of vsbys at or below 2SM generally along and east
of a line from KCOU to KPPQ. Snowfall intensity and lower end IFR
conditions will increase this afternoon as the disturbance moves
through, and additional lift is provided by and advancing surface
cold front. Snow will end behind the cold front as drier air works
its way into the area. Low end MVFR ceilings will likely trail
the cold front by a few hours before scattering out late this
evening/overnight as the dry air deepens. Expect gusty northwest
flow and VFR conditions on Monday as high pressure builds across
the Great Plains.
Specifics for KSTL:
Generally expect MVFR flight conditions early this afternoon with
increasing snowfall intensity leading to IFR conditions by mid-
afternoon. Moderate to occasionally heavy snow is possible for a
brief period ahead of an approaching cold front as it interacts
with an upper level disturbance. Preferred not to include vsbys
below 1SM as there is still some uncertainty this will occur.
Should see conditions improve by 00Z-01Z time frame as the front
passes through. Low end MVFR cigs will likely linger behind the
front until drier air deepens enough to scatter them out late this
evening or overnight. Expect gusty northwest flow and VFR
conditions on Monday as high pressure builds across the Great
Plains.
Carney
&&
.CLIMATE:
The following are record low maximums and record low minimums for
each of the next 4 days, which corresponds to the expected length
of the current cold spell and record snowfall for St. Louis and
Columbia for Saturday and Sunday when the area is expecting the
first widespread accumulating snowfall of the season.
Date: 11/16 11/17 11/18
St. Louis
Low High: 29/1997 17/1880 25/1880
Low: 13/1959 6/1959 14/1932
Snowfall: 0.1/1997 1.0/1951
Columbia
Low High: 30/1932 23/1959 27/1903
Low: 8/1959 4/1959 8/1891
Snowfall: 4.8/1932 0.1/1989
Quincy
Low High: 28/1997 19/1959 24/1903
Low: 4/1959 3/1959 7/1903
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...WINTER WEATHER ADVISORY until 6 PM CST this evening FOR Callaway
MO-Cole MO-Crawford MO-Franklin MO-Gasconade MO-Lincoln MO-
Moniteau MO-Montgomery MO-Osage MO-Warren MO.
WINTER WEATHER ADVISORY until 9 PM CST this evening FOR Iron MO-
Madison MO-Reynolds MO-St. Francois MO-Ste. Genevieve MO.
WINTER WEATHER ADVISORY until 9 PM CST this evening FOR
Jefferson MO-St. Charles MO-St. Louis City MO-St. Louis MO-
Washington MO.
IL...WINTER WEATHER ADVISORY until 9 PM CST this evening FOR Bond IL-
Clinton IL-Fayette IL-Madison IL-Marion IL-Monroe IL-
Randolph IL-St. Clair IL-Washington IL.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1143 AM CST Sun Nov 16 2014
.SHORT TERM...(Today through Tuesday)
Issued at 345 AM CST SUN NOV 16 2014
Record breaking cold likely early this week...
Regional radars showing plenty of light snow across the region this
morning as main upper-level trough and associated cold front
continue to slide through the area. So far snowfall reports through
the overnight have been far and few between....however accumulations
of less than a half inch are likely through the remainder of the
early morning hrs. Fcst becomes a bit more interesting after 12z as
models have trended a tad further north with frontal band QPF axis
that is expected to impact the far southern zones later this morning
into early afternoon. That said...forcing for ascent looks to be
fairly decent as main upper PV lobe slides east through the course of
the day today. Additionally...models show increasing frontogenesis in
the 850-700 hPa layer as the thermal gradient increases thanks to
increasing cold air advection behind aforementioned secondary cold
front. All told...chances look fairly promising for some light
accumulations south of the KC Metro later today.
Initial look earlier this evening suggested we may need another
advisory for far southern zones to account for anticipated snowfall.
After collaboration with both SGF and LSX...have elected to hold off
on issuing any flags as snowfall accumulations will likely barely
eclipse the 1" mark. This decision is also supported by the recently
arriving 6z NAM and latest runs of the HRRR which are now trending a
bit further south than the earlier runs. In any event...can/t rule
out some minor travel problems later today and daytime shift can
issue SPS statements as needed. Further north...except for some
occasional flurries and chilly conditions as highs top out in the
middle to upper 20s.
Beyond this...story quickly turns to bitterly cold temps as the
chilliest airmass of the season descends upon the region following the
passage of another cold front (albeit dry) overnight tonight.
Following its passage...models show the -20C 850 isotherm making its
way south into northern sections of the fcst area during the day on
Monday. This should result in high temps struggling to reach 20
degrees across much of the area which combined with brisk northwest
winds...will result in single digit windchills through the day.
Confidence continues to increase that record cold high temps likely
to be reached on Monday with record lows also likely Tuesday morning
as the mercury easily falls into the single digits (see climate
section below).
Finally by Tuesday...high pressure across the far southern Plains
will begin tracking east which combined with low pressure entering
the northern Plains...should allow low-level winds to change over to
the south. The end result will be daytime highs climbing back into
the upper 20s to lower 30s Tuesday afternoon with the moderation
trend expected to continue through midweek.
.LONG TERM...(Wednesday through Saturday)
Issued at 345 AM CST SUN NOV 16 2014
The extended continues to look cold and dry for the first half of
the extended before precipitation chances increase towards the end
the work week. Models start out in good agreement at the beginning
of the period on Wednesday with the upper level pattern revealing
upper level troughing over the Great Lakes and Ohio River Valley and
upper level ridging over the western CONUS. Northwest flow aloft
will still be in place over the area however, it will relax a bit
from the very cold temperatures that will affect the area on Monday
and Tuesday. Expect highs in the lower 30s to lower 40s. The model
solutions begin to diverge during this time period with the GFS
keeping the area under northwest flow again Thursday before the
pattern becomes more zonal Thursday through Saturday. The EC depicts
a reinforcing upper trough digging through the Midwest Thursday into
Friday which would reinforce the cold pattern in place. The Canadian
is a middle of the road solution. Have maintain a blended solution
to account for models differences.
The models do come into some agreement with the main feature of
interest in the extended in the form of an upper level trough. This
trough will move from the southwestern Conus into the western High
Plains on Saturday. Warm air advection showers will be underway on
Saturday ahead of the system. The main question is how this system
will evolve. The GFS is progressive with this system in moving a
open wave through the area Saturday night into Sunday. The EC digs
and slows the trough as it moves into the Plains Saturday and Sunday
and closes a low in the base of the trough across Oklahoma on
Sunday. this would provide for a colder and prolonged wet solution.
As such, have chance POPs with rain or snow wording in the forecast
for Saturday night and Sunday to account for difference in
solutions.
&&
.AVIATION...(For the 18Z TAFS through 18Z Monday Afternoon)
Issued at 1140 AM CST SUN NOV 16 2014
The northern end of a band of snow with IFR cigs will clear west
central MO by mid afternoon. Otherwise, VFR cigs for all four
terminals with a gradual west to east clearing of higher based
clouds. A windshift line over central NE will press southeast
overnight with westerly winds veering to the northwest and increasing
with its passage.
Expect strong and gusty northwest winds shortly after sunrise Monday
morning with low-end VFR cigs forming by mid-morning. Will likely see
scattered flurries or snow showers form across the entire region by
late morning or early afternoon.
&&
.CLIMATE...
Updated at 345 AM CST SUN NOV 16 2014
Monday
November 17th Current Record Low Forecast High Monday
Record Low Highs High Afternoon
--------------------------------------------------------------------
Kansas City 24 in 1891 21
St. Joseph 26 in 1951 21
Tuesday
November 18th Current Record Low Forecast Low Tuesday
Record Lows Morning
--------------------------------------------------------------------
Kansas City 14 in 1903 7
St. Joseph 16 in 1989 5
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...WINTER WEATHER ADVISORY until 4 PM CST this afternoon FOR KSZ060.
MO...WINTER WEATHER ADVISORY until 4 PM CST this afternoon FOR MOZ053-
054.
&&
$$
SHORT TERM...32
LONG TERM...73
AVIATION...MJ
CLIMATE...Cutter
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
1231 PM MST SUN NOV 16 2014
.UPDATE...
ALLOWED SOME OF THE NORTHERN AND WESTERN WINTER HIGHLIGHTS TO
EXPIRE AS SCHEDULED. EXTENDED SOME EAST CENTRAL ADVYS AND
WARNINGS TO 4 PM WITH HRRR SHOWING SOME ADDITIONAL SNOW THERE.
LOWERED SOME MAX TEMPS.
&&
.PREV DISCUSSION...1057 AM MST SUN NOV 16 2014...
.AVIATION...
18Z TAF CYCLE
MIX OF IFR/LIFR CONDITIONS DUE TO AREAS OF SNOW MAINLY SOUTH OF
CAO TO SAF LINE WILL STEADILY SINK SOUTH AND EAST THROUGH THE DAY.
BY ROUGHLY 21Z OR 22Z THE NORTH END OF THESE LOWER CIGS AND
PATCHY SN SHOULD BE IN VCNTY OF CVN TO CORONA LINE. ELSEWHERE
SHOULD BE PREDOMINANTLY VFR WITH SOME OCCASIONAL MT OBSCURATIONS.
GREATEST TAF SITE IMPACTS SHOULD BE LVS...TCC AND ROW WITH ROW
IMPACTS LASTING THE LONGEST. EXPECT VFR CONDITIONS FOR TONIGHT AND
MON...THOUGH THERE MAY BE SOME LOCALIZED LOW CIGS AND FOG IN SOME
OF THE HIGHER MT BASINS BETWEEN ROUGHLY 07Z AND 15Z MON AS THE LOW
LVL INVERSION FORMS. MUCH DRIER AIR WILL BE GETTING MORE STRONGLY
IN PLACE...LIKELY NEGATING WIDESPREAD FOG POTENTIAL.
43
&&
.PREV DISCUSSION...317 AM MST SUN NOV 16 2014...
.SYNOPSIS...
THE FIRST WINTER WEATHER EVENT OF THE SEASON FOR MANY LOWER
ELEVATION LOCATIONS IS UNDERWAY...WITH SNOW LEVELS EXPECTED TO
CONTINUE TO DROP THIS MORNING TO INCLUDE MOST OF NORTHERN AND
CENTRAL NEW MEXICO. WINTER WEATHER HIGHLIGHTS ARE IN EFFECT FOR
MUCH OF THE AREA. THIS SYSTEM WILL BE A QUICK-HITTER...WITH SNOW
ENDING LATER TODAY. A BITTER COLD NIGHT IS ON TAP...WITH MONDAY
MORNING LOW TEMPERATURES FORECAST TO BE NEAR RECORD VALUES AT A
NUMBER OF LOCATIONS. VERY DRY CONDITIONS WITH BELOW TO WELL BELOW
NORMAL TEMPERATURES WILL CONTINUE INTO MID WEEK WITH A SLOW
WARMING TREND. TEMPERATURES WILL BE BACK CLOSER TO SEASONAL
AVERAGES BY THE END OF THE WORK WEEK PRIOR TO ANOTHER STRONG COLD
FRONT PUSHING THROUGH NEXT WEEKEND.
&&
.DISCUSSION...
ALL THE NECESSARY INGREDIENTS ARE COMING TOGETHER NICELY THIS
MORNING FOR WHAT WILL BE THE FIRST WINTER WEATHER EVENT OF THE
SEASON FOR A NUMBER OF LOWER ELEVATION LOCATIONS. A POTENT UPPER
LEVEL TROUGH OVER THE GREAT BASIN IS PROGRESSING RAPIDLY SOUTHEAST
TOWARD NEW MEXICO. 00Z UPPER AIR DATA REVEALED VERY COLD
TEMPERATURES ALOFT WITH THIS TROUGH...-31C AT 500MB AND -15C AT
700MB. THE PRECEDING BACKDOOR COLD FRONT IS PLENTY COLD...THOUGH
NOT AS COLD AS THE ARCTIC AIRMASS FROM THIS PAST WEEK. SURFACE
TEMPERATURES BEHIND THE FRONT ARE IN THE TEENS AND 20S...WITH SOME
SINGLE DIGITS JUST NOW SHOWING UP NEAR THE COLORADO BORDER ACROSS
FAR NE NM. THE FRONT-DOOR PORTION OF THE FRONT WILL BE PUSHING
THROUGH WESTERN NEW MEXICO TODAY...WITH BREEZY TO WINDY CONDITIONS
BEHIND IT. IN THE MEANTIME...PRECIPITATION IS BREAKING-OUT ACROSS
EASTERN AZ AND MUCH OF NORTHERN AND CENTRAL NM WITH OCCASIONAL
LIGHTNING. OUR POPS HAVE TRENDED UP FURTHER WITH OUR FORECAST
CONFIDENCE. HAVE EXPANDED THE WINTER WEATHER ADVISORY TO INCLUDE
ZONES FROM THE SOUTH CENTRAL HIGHLANDS AND MOUNTAINS EAST TO THE
TEXAS BORDER. OF THOSE ZONES...THE SOUTH CENTRAL MOUNTAINS HAS THE
GREATEST POTENTIAL TO PILE UP SOME SNOW TODAY...WITH AMOUNTS
RANGING FROM 3-5 INCHES (LOCALLY HIGHER ABOVE 9000 FEET). THE ONLY
LIMITING FACTOR WITH THIS EVENT IS DURATION...AS THIS SYSTEM WILL
BE QUICK-HITTING WITH SNOW ENDING FROM NORTH TO SOUTH FROM MID DAY
THROUGH THE AFTERNOON HOURS.
IN THE ALBUQUERQUE METRO...MIXED PRECIPITATION INITIALLY AND WARM
GROUND TEMPERATURES WILL SIGNIFICANTLY LIMIT THE POTENTIAL FOR
WINTER WEATHER IMPACTS. UP TO 2 INCHES OF ACCUMULATING SNOW...
MAINLY ON GRASSY SURFACES...IS POSSIBLE OUT ON THE WEST MESA AND IN
THE FOOTHILLS.
A FRIGID COLD NIGHT IS EXPECTED...WITH MONDAY MORNING LOWS NEAR
OR BELOW RECORD VALUES AT A NUMBER OF LOCALES. RAPID CLEARING
BEHIND THE EXITING TROUGH AND FRESH SNOW ON THE GROUND WILL BE
CONTRIBUTING FACTORS...WITH OUR FORECAST LOWS GENERALLY AT OR
BELOW THE COLDEST AVAILABLE GUIDANCE. THIS COLD AIRMASS TO HANG-ON
THROUGH MIDWEEK WITH A SLOW WARMING TREND AND TEMPERATURES BELOW
TO WELL BELOW NORMAL. TEMPERATURES ARE FORECAST TO BE NEAR NORMAL
TOWARD THE END OF THE WEEK...BUT HIGHLY DEPENDENT ON THE TIMING OF
A SHORTWAVE TROUGH MOVING THROUGH IN THE WESTERLIES. BOTH THE 00Z
GFS AND ECMWF AGREE ON THE TIMING OF A FAST-MOVING SHORTWAVE
TROUGH FRIDAY NIGHT INTO SATURDAY...BUT THEN DIFFER THE NEXT TROUGH
ON SUNDAY ACCOMPANIED BY A STRONG COLD FRONT. FORECASTER
CONFIDENCE GENERALLY LOW BEYOND FRIDAY AT THIS POINT.
11
&&
.FIRE WEATHER...
UNSETTLED WEATHER TODAY WITH VIGOROUS COLD FRONTAL PASSAGE THEN
TRENDING DRIER WITH REDUCED VENTILATION THROUGH AT LEAST MIDWEEK.
SIGNIFICANT MID LEVEL DRY INTRUSION WILL PROVIDE UNUSUALLY LOW RH
READINGS WESTERN AND SOME CENTRAL AREAS BY MID WEEK.
A STRONG COLD FRONT HAS ALREADY SWEPT ACROSS THE EASTERN PLAINS AND
HAS ABUTTED UP TO THE CENTRAL MOUNTAINS. THE MORE TRADITIONAL COLD
FRONT HAS NUDGED INTO NORTHWEST NM AND WILL ALSO SWEEP ACROSS
WESTERN AND CENTRAL AREAS THIS MORNING. TEMPERATURES WILL BE WELL
BELOW NORMAL TODAY. WETTING PRECIPITATION...MAINLY IN THE FORM OF
SNOW WILL FAVOR THE EAST SLOPES OF THE CENTRAL MTNS AS WELL AS THE
HIGHER WEST FACING SLOPES OF THE WESTERN HIGHLANDS AND NORTH CENTRAL
MTNS. BREEZY TO LOCALLY WINDY NORTHWEST WINDS EXPECTED BEHIND THE
FRONT WESTERN/CENTRAL AREAS. CLEARING SKIES AND MUCH DRIER
CONDITIONS WILL PREVAIL AFTER THE DAYTIME PERIOD TODAY.
THE MAIN THEME THROUGH THE EARLIER HALF OF THE WEEK APPEARS TO BE
TWO FOLD...REDUCED VENTILATION WITH LOTS OF POOR RATINGS AND DRY
AIR. DEWPOINTS WILL LOWER SUBSTANTIALLY DUE TO THE COLD AIR MOVING
IN FROM THE NORTH TODAY/TONIGHT. DURING THE EARLIER HALF OF NEXT
WEEK...A MID LEVEL DRY INTRUSION WILL EXPAND AND PROVIDE ADDITIONAL
DRYING...ESPECIALLY OVER THE HIGHER MOUNTAIN RIDGES/MID SLOPE AREAS.
THIS PARTICULAR DRY INTRUSION OR DRY SLOT APPEARS TO BE SIGNIFICANT BASED
ON THE LATEST MODEL FORECASTS. PEAKING IN COVERAGE AND STRENGTH ON
WEDNESDAY. DESPITE THE UNUSUALLY LOW MIXING HEIGHTS...THE STRENGTH
OF THE DRY SLOT WILL CERTAINLY IMPACT SURFACE CONDITIONS SO WENT
LOWER THAN MODEL DEWPOINT GUIDANCE ACROSS THE HIGHER TERRAIN.
TEMPERATURES WILL GRADUALLY WARM BUT WILL BE A SLOW PROCESS TO GET
BACK TO NEAR NORMAL ACROSS THE WEST ON WEDNESDAY. STILL 5 TO 10
DEGREES BELOW NORMAL ACROSS THE EAST DUE TO A WEAK BACK DOOR COLD
FRONT ON WEDNESDAY. SOME NW BREEZES WILL BE FOUND ALONG A LINE FROM
FARMINGTON TO ALBUQUERQUE TO CLINES CORNERS MONDAY BUT LOWER
TUESDAY AND WEDNESDAY AS THE GRADIENT ALOFT REDUCES.
MODELS STILL SHOW A WEAK PACIFIC WAVE PASSAGE ON THURSDAY. NOT A LOT
OF FANFARE WITH THIS SYSTEM PASSAGE. LOOKS TO BE PRETTY DRY ALTHOUGH
THE LATEST GFS SHOWS SOME LIGHT SHOWERS. THE GFS IS STRONGER WITH
THIS WAVE PASSAGE THAN THE ECMWF/CANADIAN MODELS. VENTILATION SHOULD
BUMP UP WITH THE WAVE PASSAGE DUE TO IMPROVED MIXING HEIGHTS AND
THIS BEARS OUT IN OUR GRIDDED FORECAST.
ALL OF THE MODELS SHOW SOME SORT OF WEAK RIDGING OVER THE AREA
FRIDAY AHEAD OF ANOTHER PACIFIC WAVE. MIXING HEIGHTS SHOULD LOWER
SLIGHTLY ALTHOUGH TRANSPORT WINDS APPEAR TO INCREASE SO VENTILATION
RATES SHOULD INCREASE A LITTLE BIT MORE. CONFIDENCE IS A LITTLE
SHAKY FOR THE VENTILATION FORECAST ON FRIDAY. DRIER CONDITIONS WOULD
CONTINUE.
BOTH THE ECMWF/GFS ARE PRETTY SIMILAR IN DRAGGING A SECOND AND
PERHAPS MORE POTENT PACIFIC WAVE OVER THE AREA ON SATURDAY. PERHAPS
A BIT MORE POTENTIAL FOR SOME SHOWER ACTIVITY DUE TO A STRONGER TROUGH
PRESENCE LATE ON THE WEEKEND TO EARLY THE FOLLOWING WEEK.
50
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 4 PM MST THIS AFTERNOON FOR THE
FOLLOWING ZONES...NMZ521-522-524-526-533>540.
WINTER STORM WARNING UNTIL 4 PM MST THIS AFTERNOON FOR THE
FOLLOWING ZONES...NMZ523.
&&
$$
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
112 PM EST SUN NOV 16 2014
.SYNOPSIS...
EXPECT COLD AND QUIET CONDITIONS THIS AFTERNOON...WITH A STORM SYSTEM
MOVING IN TONIGHT BRINGING MIXED PRECIPITATION TO THE AREA INTO
MONDAY. FOLLOWING THIS SYSTEM...ARCTIC AIR AND LAKE EFFECT SNOW
SHOWERS CAN BE EXPECTED THROUGH THE MIDDLE PART OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
1000 AM UPDATE...MADE SOME MINOR ADJUSTMENTS TO TEMPERATURES FOR
AFTERNOON AND HAVE SOME FLURRIES INITIALLY LATE MORNING TAPERING
DOWN. CONSIDERING WINTER WEATHER ADVISORIES FOR MOST OF OUR
FORECAST AREA LATE TONIGHT/MON AM...EXCEPT THE FINGER LAKES. WAITING
FOR MORE 12Z MORNING GUIDANCE AND WILL MAKE A DECISION BY EARLY
AFTERNOON.
645 AM UPDATE...
AS ANTICIPATED...VERY LIGHT FLURRIES HAVE MANAGED TO MATERIALIZE
AS ZONE OF WEAK ISENTROPIC LIFT ALOFT IS PASSING THROUGH. VIRGA
REPRESENTS MOST OF THE RADAR RETURNS...BUT OLEAN AND WELLSVILLE
MANAGED BRIEF FLURRIES...AND NOW ITHACA AS WELL. HRRR AND RUC
FINALLY CAUGHT UP TO IT...BUT THE FLURRIES ARE STILL ABSENT IN THE
MAIN OPERATIONAL SYNOPTIC MODELS. GRIDS TWEAKED WHERE NEEDED TO
MATCH MINOR TEMPERATURE DETAILS AND SUCH...BUT FORECAST ON TRACK.
PREVIOUS DISCUSSION...
FAIRLY QUIET YET COLD CONDITIONS WILL CLOSE OUT THE WEEKEND TODAY.
THOUGH THERE IS DRY AIR IN THE LOWEST FEW THOUSAND FEET...MODEL
SOUNDINGS ESPECIALLY KITH-KSYR LATER THIS MORNING SHOW SATURATION
IN THE 5 TO 15 KFT AGL LAYER...WEAK LIFT...AND NEARLY ISOTHERMAL
DENDRITIC GROWTH TEMPERATURES /ROUGHLY 10 TO 20 BELOW ZERO
CELSIUS/. MINOR ISENTROPIC LIFT ALSO OCCURS ON THE 290-295K
SURFACES...A RESULT OF WARM AIR ADVECTION ALOFT AHEAD OF THE NEXT
SYSTEM. SO DESPITE LACK OF QPF IN OPERATIONAL MODELS...I BELIEVE
ABILITY FOR GENERATING DENDRITE FLURRIES WILL BE THERE...THE
QUESTION IS WILL THEY SURVIVE THEIR TRIP THROUGH THE LOW LEVEL DRY
AIR. I ADDED CHANCE OF FLURRIES FROM FINGER LAKES THROUGH NY
THRUWAY AREAS LATER THIS MORNING...BUT WHATEVER FALLS /IF ANY/
WILL NOT BE MEASURABLE.
HIGHS TODAY GENERALLY UPPER 30S-MID 40S...ROUGHLY 5-8 DEGREES ABOVE
SATURDAY YET STILL A WAYS BELOW CLIMATOLOGY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
430 AM UPDATE...
THE TREND CONTINUES TO BE WARMER WITH EACH PASSING MODEL RUN
REGARDING THE NEXT SYSTEM LATER TONIGHT THROUGH MONDAY AND THAT
WILL TRANSLATE INTO A FASTER CHANGE TO ALL RAIN IN MANY AREAS.
PRECIP STILL ON TRACK TO ARRIVE SHORTLY AFTER MIDNIGHT AND AT THE
ONSET, MOSTLY ALL SNOW FOR EVERYONE. MODEL SOUNDINGS DO SHOW RAIN
AT THE ONSET IN PLACES SUCH AS KAVP. I BELIEVE EVEN HERE HOWEVER
EVAPORATE COOLING SHOULD GIVE A BRIEF PERIOD OF SNOW OR EVEN SOME
ICE PELLETS AT THE START. WARMING ALOFT MOVES IN QUICK WITH MODEL
CONSENSUS SHOWING THE 850 MB 0C LINE UP TO NEAR KBGM BY 12Z AND
APPROACHING KSYR BY 18Z. AT THE SAME TIME BOUNDARY LAYER TEMPS
THAT ARE MARGINAL AT THE START, WILL WARM ESPECIALLY IN THE LOWER
ELEVATIONS. THIS MAKES SENSE GIVEN THE PLACEMENT OF HIGH PRESSURE
OFF THE COAST, NOT IN A GOOD SPOT FOR LOCKING IN COLD AIR.
WITH THAT IN MIND LOOKING FOR A SNOW TRANSITION TO PLAIN RAIN FROM
MORNING (SOUTHEAST) TO AFTERNOON (NORTHWEST), WITH SOME SLEET AND LIMITED
ICING POSSIBLE DURING THAT TRANSITION. HIGHEST SNOW POTENTIAL FAR
NORTHWEST (BATH TO AUBURN TO BOONVILLE LINE) WHERE 0C LINE DOES
NOT MAKE IT UNTIL 18Z MONDAY. EVEN HERE HOWEVER MIX POTENTIAL WILL
CUT DOWN ON SNOWFALL TOTALS AND STILL THINKING IN THE 2 TO 4 INCH
RANGE AT BEST.
BEST POTENTIAL FOR SOME FREEZING RAIN WILL OCCUR EARLIER IN THE
DAY AND THAT WILL FAVOR NORTHEAST PA AND SULLIVAN COUNTY, NY.
NO ICING IS EXPECTED IN WILKES-BARRE/SCRANTON AREA BUT LIGHT ICING IS
POSSIBLE IN THE POCONOS, ALONG WITH WAYNE COUNTY, PA AND
SULLIVAN, NY. THESE ARE TYPICAL COLD SPOTS AND NORMAL LAST HOLD
OUTS FOR COLD AIR. ANY AMOUNT OF ICE JUSTIFIES A WINTER ADVISORY
AND AFTER COORDINATION WITH PHILLY, NYC, AND ALBANY THIS WAS GIVEN
A STRONG CONSIDERATION FOR THESE AREAS ONLY. FARTHER NORTH AND
WEST ICING LOOKS MUCH MORE LIMITED AND SNOWFALL AMOUNTS DO NOT
MEET CRITERIA.
I DECIDED NOT TO DO AN ADVISORY BECAUSE THE WARMING TREND HAS BEEN
SIGNIFICANT ENOUGH THAT OUR ICING PERIOD MAY BE VERY BRIEF AND
PERHAPS EVEN COVERED BY A SPECIAL WEATHER STATEMENT LATER TODAY.
BOTTOM LINE IS THIS FORECAST IS STILL VERY MUCH UP IN THE AIR AND I
FEEL CONFIDENCE WILL BE A BIT BETTER WITH ANOTHER SET OF MODEL
RUNS UNDER OUR BELT. NO MATTER WHAT, ICING AMOUNTS ARE NOT
EXPECTED TO BE VERY MUCH AT ALL.
BY MONDAY EVENING AS THE SYSTEM MOVES OUT, A DRY SLOT SHOULD END
THE PRECIPITATION ACROSS MOST OF THE AREA. WE WILL SEE COLDER AIR
ONT HE BACKSIDE SOME A BRIEF PERIOD OF LIGHT SNOW IS POSSIBLE BUT
AMOUNTS WOULD BE MINIMAL GIVEN THE DRY SLOT.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
415 AM UPDATE...
IT IS MID NOVEMBER SO SOME COLD AIR IS NOT UNUSUAL. HOWEVER...THE
AIR MASS THAT SWINGS THROUGH TUESDAY-WEDNESDAY ACTUALLY IS QUITE A
BIT ANOMALOUS...MORE TYPICAL OF MID WINTER. 500MB HEIGHTS REACH
THREE STANDARD DEVIATIONS BELOW NORMAL...WHILE 1000-500MB
THICKNESS DIVES TO ONLY ABOUT 505 DECAMETERS. HIGHS TUESDAY-
WEDNESDAY MAINLY IN 25-32 DEGREE RANGE...LOWS TUESDAY NIGHT MID
TEENS-LOW 20S. WINDS ALSO FAIRLY STOUT WHICH WILL MAKE SINGLE
DIGIT TO TEENS WIND CHILLS COMMON.
THE NEW SURGE OF ARCTIC AIR WILL MOVE IN VIA WSW FLOW WHICH WILL
DIRECT ACCUMULATING LAKE EFFECT MAINLY NORTH OF OUR AREA INITIALLY
TUESDAY /EXCEPT FOR SOME OF LAKE ERIE SNOW SHOWERS STILL CROSSING
FINGER LAKES TO MOHAWK VALLEY REGIONS TUE MORNING/. THAT BEING
SAID...THE STRONG COLD AIR ADVECTION WILL BE ONE OF THOSE
SITUATIONS WHERE JUST ABOUT EVERY CLOUD WILL BE PRODUCING
DENDRITES...AND THE FORECAST AT LEAST INCLUDES MENTION OF
SCATTERED FLURRIES FOR ALMOST THE WHOLE AREA.
PROSPECTS FOR A PASSING SHORTWAVE LATE TUESDAY...REDIRECTING LAKE
ONTARIO BAND INTO NORTHERN ONEIDA COUNTY /WITH UPSTREAM LAKE-TO-
LAKE CONNECTIONS/...IS BECOMING APPARENT IN LATEST MODEL GUIDANCE
SUITE. IF THIS HOLDS UP...A SIGNIFICANT AMOUNT OF LOW WATER
CONTENT FLUFFY SNOW COULD ACCUMULATE IN NORTHERN ONEIDA COUNTY
TUESDAY NIGHT. WE WILL MONITOR UPCOMING MODELS AND UPDATE FORECAST
ACCORDINGLY IF CONFIDENCE INCREASES. LAKE ERIE MOISTURE WILL ALSO
MOVE BACK ACROSS MUCH OF CENTRAL NEW YORK...INCLUDING POTENTIAL
ACCUMULATIONS TOWARDS STEUBEN/YATES COUNTIES.
PREVIOUS DISCUSSION...
AFTER THU SIGNIFICANT MODEL DIFFERENCES DEVELOP WITH THE EURO
TRACKING A SFC LOW DOWN THE ST LAWRENCE RIVER VALLEY AND THE GFS
KEEPING A COLD MORE W-NW FLOW OF AIR OVER THE REGION. FOR GRIDS
KEPT IDEA OF LES SNOWS DEVELOPING AS THE WINDS TURN MORE NWRLY THU
NGT-SAT SIMILAR TO GFS. THE 12Z EURO WUD SUGGEST A LIGHT SNOW
EVENT FOR MUCH OF NE PA/C NY FRI WITH MORE LES IN ITS WAKE.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
18Z UPDATE... VFR CONDITIONS EXPECTED THROUGH THIS EVENING WITH
CLOUD BASES GRADUALLY LOWERING TO 3-4 KFT. LIGHT PRECIPITATION
WILL OVERSPREAD THE AREA AFTER MIDNIGHT. THE PRECIPITATION WILL
PROBABLY START AS A PERIOD OF LIGHT SNOW... CHANGING TO RAIN FROM
SOUTH TO NORTH THROUGH MID-MORNING MONDAY. THERE MAY BE A BRIEF
PERIOD OF FREEZING RAIN DURING THE CHANGE-OVER ESPECIALLY AT BGM
AND RME. IFR VSBYS WILL ACCOMPANY THE LIGHT SNOW OVERNIGHT WITH
MAINLY MVFR AFTER THE CHANGE TO ALL RAIN AFTER 12Z.
WINDS WILL BE SOUTH-SOUTHEAST AT 5 TO 10 KTS IN MOST AREAS THROUGH
MONDAY.
OUTLOOK...
MON-MON NGT...RESTRICTIONS IN MIXED PRECIPITATION THEN BACK TO
SCATTERED SNOW SHOWERS.
TUE TO WED...RESTRICTIONS IN LAKE EFFECT -SHSN...ESP RME AND SYR.
THUR...RESTRICTIONS POSSIBLE AT RME AND SYR OTHERWISE VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO 10 AM EST
MONDAY FOR PAZ038>040.
WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO 8 AM EST
MONDAY FOR PAZ043-044-047-048-072.
NY...WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO 10 AM EST
MONDAY FOR NYZ009-022>025-036-037-044>046-055>057-062.
&&
$$
SYNOPSIS...DJN/MDP
NEAR TERM...DJN/MDP
SHORT TERM...HEDEN
LONG TERM...DJN/MDP
AVIATION...MDP/MSE
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1200 PM CST SUN NOV 16 2014
.UPDATE...
ISSUED AT 1200 PM CST SUN NOV 16 2014
REGIONAL RADARS INDICATE MESOSCALE SNOW BANDS DEVELOPING OVER MOST
OF WESTERN AND CENTRAL NORTH DAKOTA EARLY THIS AFTERNOON. ADDED
SCATTERED SNOW SHOWERS TO ALL ZONES FOR THIS AFTERNOON AS A RESULT.
THESE BANDS HAVE BRIEFLY CAUSED VISIBILITIES TO BE REDUCED TO ONE
QUARTER MILE AT TIMES. HETTINGER WAS AFFECTED BY A BAND AND WENT
DOWN TO ONE QUARTER MILE VISIBILITY FOR ABOUT AN HOUR FROM
1619Z-1717Z. HETTINGER IS NOW BACK UP TO ALMOST TWO MILES
VISIBILITY. IT WAS THE ONLY OB IN SOUTHWESTERN NORTH DAKOTA WITH
THESE CONDITIONS. ALL OTHER OBS AND REGIONAL WEBCAMS CONTINUE TO
OBSERVE VISIBILITY GREATER THAN ONE HALF A MILE ACROSS
SOUTHWESTERN AND SOUTH CENTRAL NORTH DAKOTA.
GIVEN THE BRIEF NATURE OF LOW VISIBILITIES AND CONSIDERING THAT
BLIZZARD WARNING CRITERIA IS 35 MPH WINDS...AND ONE QUARTER MILE
VISIBILITY FOR THREE HOURS OR LONGER...STILL THINK THE WINTER
WEATHER ADVISORY FOR BLOWING SNOW LOOKS GOOD. WILL MAINTAIN THE
CURRENT CONFIGURATION OF THE WSW AND NPW FOR THIS UPDATE.
UPDATE ISSUED AT 957 AM CST SUN NOV 16 2014
MSAS ANALYSIS CONTINUES TO INDICATE A 6MB/3HR PRESSURE RISE RACING
SOUTHEAST ACROSS EASTERN MONTANA. THE INITIAL SURGE/ISALLOBARIC
WIND GUSTS HAVE BEEN NEAR 45 MPH. REGIONAL WEBCAMS SHOWED
VISIBILITIES BEING REDUCED BETWEEN ONE TO ONE HALF MILE WITH THE
INITIAL SURGE. HOWEVER...VISIBILITIES WERE IMPROVING BEHIND THE
FRONT WITH BEACH NOW REPORTING 2 MILE VISIBLITIES.
WILL CONTINUE WITH THE CURRENT WINTER WEATHER ADVISORY FOR BLOWING
SNOW AND WIND ADVISORY CONFIGURATION FOR THIS UPDATE. WILL
CONTINUE TO MONITOR CONDITIONS TODAY IN CASE HEADLINES NEED TO BE
UPDATED. OTHERWISE...ONLY UPDATED THE WSW AND NPW TO CHANGE
"SUNDAY" WORDING TO "TODAY". THE UPDATED PRODUCTS HAVE BEEN SENT.
UPDATE ISSUED AT 632 AM CST SUN NOV 16 2014
THE FOCUS FOR THE REMAINDER OF THE MORNING WILL BE ON THE
EVOLUTION OF THE PRESSURE RISE BUBBLE JUST ENTERING NORTHEAST
MONTANA IN THE WAKE OF THE COLD FRONT AS OF 12 UTC. THIS PRESSURE
RISE BUBBLE OBSERVED AROUND 6MB/3 HR...IS STRONGER THAN PREVIOUSLY
FORECAST WITH THE 00 UTC DETERMINISTIC SUITE. THESE STRONGER
PRESSURE RISES ARE NOW BEING CAPTURED BY THE 06 UTC NAM/GFS AND 11
UTC RAP...WHICH PROPAGATE THE RISE BUBBLE DIRECTLY OVER THE
DEEPEST SNOW PACK OF THE SOUTHWEST LATE THIS MORNING. GIVEN THE
POTENTIAL FOR POSSIBLY STRONGER ISALLOBARIC FORCING...THE SOUTHWEST
WILL HAVE TO BE CLOSELY MONITORED SHOULD AN UPGRADE TO A BLIZZARD
WARNING BECOME NECESSARY.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 340 AM CST SUN NOV 16 2014
A WINTER WEATHER ADVISORY AND A WIND ADVISORY CONTINUE TO HEADLINE
THE SHORT TERM PERIOD. A STRONG COLD FRONT WILL PUSH ACROSS THE
NORTH BEGINNING AROUND 12Z AND MAKE ITS WAY TO THE SOUTHERN BORDER
BY 18Z. STRONG WINDS WILL FOLLOW THE FRONT WITH BLOWING/DRIFTING
SNOW IN THE WINTER WEATHER ADVISORY AREA. ONLY CHANGE TO THE ONGOING
WINTER WEATHER ADVISORY WAS TO ADD KIDDER COUNTY SINCE THEIR
SNOWFALL TOTAL LAST WEEKEND WAS COMPARABLE WITH BURLEIGH COUNTY.
GUSTY WINDS ARE SIMILAR IN BOTH LOCATIONS TODAY.
CURRENT WATER VAPOR IMAGERY SHOWS A POTENT SHORTWAVE WITH
SUBSIDENCE/DARKENING SIGNATURE PUSHING INTO SOUTHERN SASKATCHWEAN.
AT THE SURFACE...CURRENT ANALYSIS PLACES 3HR PRESSURE FALLS OF
6MB ACROSS NORTHWEST NORTH DAKOTA. THE COLD FRONT IS APPROXIMATELY
LOCATED FROM KALISPELL MONTANA TO SWIFT CURRENT SASKATCHEWAN...AND
NORTHEAST INTO LAKE WINNIPEG MANITOBA. THE MAXIMUM 3HR PRESSURE
BUBBLE OF 4 TO 5 MB IS LOCATED OVER SOUTHEAST ALBERTA. THE RAP13
HAS A GOOD HANDLE ON THE CURRENT FRONTAL LOCATION AND LOCATION/MAGNITUDE
OF CURRENT PRESSURE FALL/RISE COUPLET. EXPECT THE MAX PRESSURE
FALLS BETWEEN DICKINSON AND BISMARCK BY 12Z...WITH PRESSURE RISES
PUSHING INTO NORTHWEST NORTH DAKOTA BETWEEN 12Z-15Z SIGNIFYING THE
PASSAGE OF THE COLD FRONT. HENCE THE CURRENT TIMING OF THE
AFOREMENTIONED WINTER WEATHER ADVISORY AND WIND ADVISORY ALL LOOK
ON TRACK. OVERALL...AN AVERAGE RANGE OF SUSTAINED/MAX GUSTS PER
NAM/GFS/RAP BUFKIT SOUNDINGS AND THE 80M HRRR SHOWS NORTHWEST
WINDS SUSTAINED BETWEEN 25KT-35KT...AND GUSTS OF 35KT-45KT.
LOW CLOUDS ALONG WITH ISOLATED TO SCATTERED SNOW SHOWERS WILL ALSO
ACCOMPANY THE FRONTAL PASSAGE. ALTHOUGH THE STRONGEST WINDS WILL
EXIT BY EARLY EVENING...WINDS WILL REMAIN GUSTY THROUGH THE NIGHT
WITH LOW LEVEL ADIABATIC MIXING CONTINUING.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 340 AM CST SUN NOV 16 2014
A POTENTIAL MODERATION IN TEMPERATURES LATE THIS WEEK HIGHLIGHTS
THE EXTENDED FORECAST.
THE 00 UTC SUITE IS IN AGREEMENT ON THE ANOMALOUS HIGH AMPLITUDE
UPPER LEVEL PATTERN ACROSS NORTH AMERICA BREAKING DOWN TO A NEAR
ZONAL PATTERN BY NEXT WEEKEND IN A BROAD VERY LOW AMPLITUDE
TROUGH. THIS WOULD SIGNAL A RECOVERY FROM THE ARCTIC TEMPERATURES
TO STILL BELOW NORMAL...YET MORE TOLERABLE HIGHS NEAR FREEZING BY
NEXT WEEKEND. THE EXTENDED FORECAST LOOKS TO BE PRECIPITATION FREE
LACKING THE NEEDED MOISTURE RECOVERY FROM THE ARCTIC AIRMASS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1200 PM CST SUN NOV 16 2014
NORTHWESTERLY WIND GUSTS UP TO 40 KNOTS WILL CONTINUE OVER WESTERN
AND CENTRAL NORTH DAKOTA THIS AFTERNOON. TEMPO MVFR/IFR CONDITIONS
IN LIGHT SNOW AND BLOWING SNOW WILL BE POSSIBLE...MAINLY OVER
KDIK. WINDS SHOULD BEGIN TO TAPER OFF SOMEWHAT OVERNIGHT AS HIGH
PRESSURE BUILDS INTO WESTERN NORTH DAKOTA. HOWEVER...MVFR CIGS ARE
EXPECTED TO DEVELOP AREAWIDE TONIGHT ON THE BACK SIDE OF A LOW
EXITING THE NORTHERN PLAINS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 6 AM CST /5 AM MST/ MONDAY FOR
NDZ017>020-031>034-040>045.
WIND ADVISORY UNTIL 9 PM CST THIS EVENING FOR NDZ001>003-009>011-
021.
WIND ADVISORY UNTIL 9 PM CST THIS EVENING FOR NDZ004-005-012-013-
022-023-025-037-048.
WINTER WEATHER ADVISORY UNTIL 6 AM CST MONDAY FOR NDZ035-036-046-
047-050-051.
&&
$$
UPDATE...TM
SHORT TERM...KS
LONG TERM...AYD
AVIATION...TM
THE SHORT TERM FORECAST DISCUSSION WILL BE UPDATED SHORTLY.
SNOW WILL TAPER OFF FROM WEST TO EAST ON MONDAY MORNING...WITH
LITTLE ADDITIONAL ACCUMULATION AFTER AROUND 6AM (WESTERN CWA) TO
9AM (EASTERN CWA). PRECIPITATION WILL END SEVERAL HOURS BEFORE THE
SURFACE COLD FRONT IS FORECAST TO ARRIVE. WHEN IT DOES (15Z-21Z
ACROSS THE CWA)...A STRONG PUSH OF COLD ADVECTION WILL BEGIN. THIS
WILL HAVE AN IMPACT ON WEATHER CONDITIONS BEYOND JUST
TEMPERATURES...AS A SUDDENLY WELL-MIXED BOUNDARY LAYER WILL
GENERATE SOME WEAK INSTABILITY AT ABOUT 4000 FEET...THROUGH THE
HEART OF THE DENDRITIC GROWTH ZONE. THUS...FLURRIES (POSSIBLY EVEN
A SNOW SHOWER OR TWO) ARE QUITE LIKELY LATE MONDAY INTO MONDAY
NIGHT...AND AGAIN ON TUESDAY AFTERNOON. WESTERLY WINDS WILL ALSO
BECOME SOMEWHAT GUSTY (20-30 KNOTS)...AND WINDS ARE NOT EXPECTED
TO DIMINISH MUCH DURING THE OVERNIGHT HOURS. WITH TEMPERATURES
EXPECTED TO FALL INTO 10-15 DEGREE RANGE MONDAY NIGHT...WIND
CHILLS WILL LIKELY DROP BELOW ZERO.
MIN TEMPERATURES ON MONDAY NIGHT / EARLY TUESDAY MORNING WILL BE
DRIVEN BY STRONG COLD ADVECTION UNDER A VERY ANOMALOUS AIR
MASS...WITH TEMPERATURES AT 850MB OF AROUND -20 DEGREES CELSIUS ON
TUESDAY MORNING. THIS WORKS OUT TO ROUGHLY 3 STANDARD DEVIATIONS
BELOW NORMAL...PERHAPS EVEN CLOSE TO 3 AND A HALF. OUTSIDE OF THE
FAR SOUTHEASTERN CWA...SURFACE TEMPERATURES ARE EXPECTED TO REACH
THE LOWER TEENS TO AROUND 10 DEGREES...WITH SOME ISOLATED READINGS
IN THE SINGLE DIGITS QUITE POSSIBLE. RECORD LOWS FOR TUESDAY
MORNING (NOVEMBER 18) ARE GOING TO BE THREATENED.
CVG...12 DEGREES...1880
CMH...10 DEGREES...1880
DAY...13 DEGREES...1959
WHILE RECORDS FOR MIN TEMPERATURES ON TUESDAY ARE ONLY A
POSSIBILITY...RECORD LOW MAX TEMPERATURES ON TUESDAY SEEM A NEAR
CERTAINTY...WITH FORECAST TEMPERATURES OF UPPER TEENS TO LOWER
20S. THE RECORDS FOR LOW MAX TEMPERATURES ON NOVEMBER 18 ARE
LISTED BELOW.
CVG...26 DEGREES...1951
CMH...26 DEGREES...1903
DAY...27 DEGREES...1951 AND 1903
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
MODELS ARE IN DECENT AGREEMENT WITH SYNOPTIC SYSTEMS TUESDAY NIGHT
INTO FRIDAY...THEN DIVERGE SOME THEREAFTER. HAVE USED A BLEND OF THE
ECMWF AND GFS FOR THE IMMEDIATE LONG TERM...THEN A BLEND OF THE
GFS/WPC GOING INTO THE WEEKEND.
FOR TUESDAY NIGHT...HIGH PRESSURE IS EXPECTED TO BUILD INTO THE SE
UNITED STATES. IT WILL BEGIN TO WARM AIR ADVECT ALOFT WHICH SHOULD
PUSH STRATOCUMULUS AND FLURRY THREAT TO THE EAST DURING THE EVENING.
MID AND HIGH LEVEL CLOUDS WILL THEN INCREASE FROM THE NORTHWEST IN
ADVANCE OF THE NEXT WEATHER SYSTEM. HAVE TAKEN A BLEND OF MODELS FOR
LOWS GIVEN THERE WILL STILL BE A PRESSURE GRADIENT AND CLOUDS FROM
TIME TO TIME. WILL FORECAST 10 TO 15 DEGREES WITH WIND CHILL VALUES
MOSTLY IN THE 0 TO -5 RANGE.
S/WV AND WEAK FRONT IS EXPECTED TO PASS THROUGH THE REGION WEDNESDAY
INTO WEDNESDAY NIGHT. SYSTEM IS FAIRLY MOISTURE STARVED AND HAVE
LIMITED LOW POPS/THREAT FOR LIGHT SNOW TO THE NRN ZONES. IT WILL BE
BLUSTERY ONCE AGAIN AS TEMPERATURES WARM INTO THE LOWER AND MID
30S...ALTHOUGH THIS WILL STILL BE WELL BELOW NORMAL FOR MID
NOVEMBER.
FOR THURSDAY THROUGH FRIDAY...MODELS ARE SOMEWHAT DIFFERENT IN
REGARDS TO THE AMOUNT OF RESURGING ARCTIC AIR THAT WILL BLEED BACK
INTO OUR AREA IN ASSOCIATION WITH SFC HIGH PRESSURE. IT SHOULD BE
DRY...BUT TEMPERATURES WILL STILL BE WELL BELOW NORMAL.
MODELS KEEP ADVERTISING A PATTERN SHIFT FOR THE UPCOMING WEEKEND AS
THE LONGWAVE PATTERN WILL PUSH ARCTIC AIR BACK NORTH INTO CANADA
WHILE A SERIES OF WEATHER SYSTEMS MOVING INTO THE REGION WILL BE OF
A PACIFIC ORIGIN. THERE ARE SOME TIMING ISSUES BUT IT APPEARS THAT
RETURN FLOW/WAA PATTERN ALONG WITH A WEATHER SYSTEM WILL BRING AN
INCREASING THREAT FOR SHOWERS SATURDAY NIGHT INTO SUNDAY.
TEMPERATURES BY SUNDAY ARE FORECAST TO APPROACH NORMAL HIGHS IN THE
MID 40S TO AROUND 50 DEGREES.
&&
.AVIATION /20Z SUNDAY THROUGH FRIDAY/...
GENERALLY VFR CIGS ARE FOUND OUTSIDE OF THE HIGHER RETURNS THAT
ARE PRODUCING SOME LIGHT FLURRIES OVER PORTIONS OF CWA AND TAF
SITES. A FEW LOWER CIGS IN CENTRAL OHIO WILL MIX UPWARDS TO VFR IN
THE NEXT HOUR OR TWO THIS EARLY AFTERNOON. OTHERWISE THE EVENING
AND OVERNIGHT WILL EXPERIENCE DETERIORATING CONDITIONS AS A SNOW
STORM OVERSPREADS THE REGION. VFR CIGS WILL LOWER TO MVFR THIS
EVENING AND COMBINE WITH MVFR VSBYS IN RAIN AND SNOW...CHANGING TO
ALL SNOW THIS EVENING. WHILE ANY OF THE TAF SITES WILL EXPERIENCE
DROPS TO IFR CIGS/VSBYS IN HEAVIER PERIODS OF SNOW WHICH SHOULD BE
MORE LIKELY AFTER MIDNIGHT. A CLEARING FROM W-E WILL OCCUR
TOMORROW MORNING AS WINDS SHIFT WEST AND INCREASE TO 12KT...HIGHER
IN THE AFTERNOON.
OUTLOOK...MVFR/IFR CEILINGS AND VISIBILITIES WITH SCATTERED SNOW
SHOWERS ARE POSSIBLE MONDAY AFTERNOON/EVENING. SNOW SQUALLS AGAIN
ON TUESDAY COULD YIELD MVFR/IFR CONDITIONS AT TIMES.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO NOON EST
MONDAY FOR OHZ026-034-035-042>045-051>054-060>062.
WINTER STORM WARNING FROM 9 PM THIS EVENING TO NOON EST MONDAY
FOR OHZ063-064-070>072-077>080.
WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO 3 PM EST
MONDAY FOR OHZ046-055-056-065-073-074-081-082.
KY...WINTER STORM WARNING FROM 9 PM THIS EVENING TO NOON EST MONDAY
FOR KYZ089>093.
WINTER WEATHER ADVISORY FROM 9 PM THIS EVENING TO NOON EST
MONDAY FOR KYZ094>097.
WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO 3 PM EST
MONDAY FOR KYZ098-099.
IN...WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO NOON EST
MONDAY FOR INZ050-058-059.
WINTER STORM WARNING FROM 9 PM THIS EVENING TO NOON EST MONDAY
FOR INZ066-073>075-080.
&&
$$
SYNOPSIS...HATZOS
NEAR TERM...HATZOS
SHORT TERM...HATZOS
LONG TERM...HICKMAN
AVIATION...FRANKS
THE LONG TERM FORECAST DISCUSSION WILL BE UPDATED SHORTLY.
PREVIOUS DISCUSSION >
FOR TUESDAY NIGHT...HIGH PRESSURE IS EXPECTED TO BUILD INTO THE
SE UNITED STATES. IT WILL BEGIN TO WARM AIR ADVECT ALOFT WHICH
SHOULD PUSH STRATOCUMULUS AND FLURRY THREAT TO THE EAST DURING THE
EVENING. MID AND HIGH LEVEL CLOUDS WILL THEN INCREASE FROM THE
NORTHWEST IN ADVANCE OF THE NEXT WEATHER SYSTEM. HAVE TAKEN A
BLEND OF MODELS FOR LOWS GIVEN THERE WILL STILL BE A PRESSURE
GRADIENT AND CLOUDS FROM TIME TO TIME. WILL FORECAST 10 TO 15 WITH
WIND CHILL VALUES ONCE AGAIN IN THE 0 TO -5 RANGE.
MODELS ARE IN GOOD AGREEMENT FOR WEDNESDAY INTO WEDNESDAY
NIGHT...THEN THE ECMWF BECOMES THE ODD MODEL OUT IN THE REMAINDER OF
THE EXTENDED. HAVE GONE WITH WPC GUIDANCE WHICH FAVORS A GFS SOLUTION
AT THIS TIME.
S/WV AND WEAK FRONT IS EXPECTED TO PASS THROUGH THE REGION WEDNESDAY
INTO WEDNESDAY NIGHT. SYSTEM IS FAIRLY MOISTURE STARVED AND HAVE
LIMITED LOW POPS/THREAT FOR LIGHT SNOW TO THE NRN ZONES. IT WILL BE
BLUSTERY ONCE AGAIN AS TEMPERATURES WARM INTO THE LOWER AND MID
30S...BUT STILL WELL BELOW NORMAL FOR MID NOVEMBER.
FOR THE REMAINDER OF THE EXTENDED....COLD WEATHER WILL CONTINUE INTO
THE END OF THE WORK WEEK AS HIGH PRESSURE AND ANOTHER SHOT OF COLD
AIR MOVE INTO THE REGION. MODELS HAVE BEEN ADVERTISING A PATTERN
SHIFT BY THE WEEKEND. LOOKS LIKE LONGWAVE PATTERN WILL PUSH ARCTIC
AIR BACK NORTH INTO CANADA AS THE NEXT WEATHER SYSTEM APPROACHING
THE REGION FROM THE WEST IS OF PACIFIC ORIGIN. TEMPERATURES WILL
MODERATE INTO THE WEEKEND WITH PERHAPS A THREAT OF SHOWERS IN THE
WAA PATTERN SATURDAY AFTERNOON OR NIGHT.
&&
.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
GENERALLY VFR CIGS ARE FOUND OUTSIDE OF THE HIGHER RETURNS THAT
ARE PRODUCING SOME LIGHT FLURRIES OVER PORTIONS OF CWA AND TAF
SITES. A FEW LOWER CIGS IN CENTRAL OHIO WILL MIX UPWARDS TO VFR IN
THE NEXT HOUR OR TWO THIS EARLY AFTERNOON. OTHERWISE THE EVENING
AND OVERNIGHT WILL EXPERIENCE DETERIORATING CONDITIONS AS A SNOW
STORM OVERSPREADS THE REGION. VFR CIGS WILL LOWER TO MVFR THIS
EVENING AND COMBINE WITH MVFR VSBYS IN RAIN AND SNOW...CHANGING TO
ALL SNOW THIS EVENING. WHILE ANY OF THE TAF SITES WILL EXPERIENCE
DROPS TO IFR CIGS/VSBYS IN HEAVIER PERIODS OF SNOW WHICH SHOULD BE
MORE LIKELY AFTER MIDNIGHT. A CLEARING FROM W-E WILL OCCUR
TOMORROW MORNING AS WINDS SHIFT WEST AND INCREASE TO 12KT...HIGHER
IN THE AFTERNOON.
OUTLOOK...MVFR/IFR CEILINGS AND VISIBILITIES WITH SCATTERED SNOW
SHOWERS ARE POSSIBLE MONDAY AFTERNOON/EVENING. SNOW SQUALLS AGAIN
ON TUESDAY COULD YIELD MVFR/IFR CONDITIONS AT TIMES.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO NOON EST
MONDAY FOR OHZ026-034-035-042>045-051>054-060>062.
WINTER STORM WARNING FROM 9 PM THIS EVENING TO NOON EST MONDAY
FOR OHZ063-064-070>072-077>080.
WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO 3 PM EST
MONDAY FOR OHZ046-055-056-065-073-074-081-082.
KY...WINTER STORM WARNING FROM 9 PM THIS EVENING TO NOON EST MONDAY
FOR KYZ089>093.
WINTER WEATHER ADVISORY FROM 9 PM THIS EVENING TO NOON EST
MONDAY FOR KYZ094>097.
WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO 3 PM EST
MONDAY FOR KYZ098-099.
IN...WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO NOON EST
MONDAY FOR INZ050-058-059.
WINTER STORM WARNING FROM 9 PM THIS EVENING TO NOON EST MONDAY
FOR INZ066-073>075-080.
&&
$$
SYNOPSIS...HATZOS
NEAR TERM...HATZOS
SHORT TERM...
LONG TERM...HICKMAN
AVIATION...FRANKS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
257 PM CST SUN NOV 16 2014
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 158 PM CST SUN NOV 16 2014
PRIMARY CHALLENGES INCLUDE LIGHT SNOW TONIGHT THROUGH MONDAY AND
STRONG NORTHWEST WINDS IN THE WAKE OF AN ARCTIC FRONT THROUGH THE
DAY ON MONDAY. 16.12Z GLOBAL MODELS ARE IN GOOD AGREEMENT THROUGH
19.12Z...DIVERGING SOMEWHAT THEREAFTER IN TIMING AND STRENGTH OF
SHORT-WAVES MOVING THROUGH PARENT NORTHWEST FLOW ALOFT...BECOMING
MORE ZONAL BY NEXT WEEKEND.
16.20Z SURFACE ANALYSIS SHOWS A STRONG ARCTIC/COLD FRONT DRAPED
FROM NEAR ROSEAU MN TO ABERDEEN SD. THIS FEATURE WILL SWEEP
ACROSS THE UPPER MISSISSIPPI RIVER VALLEY OVERNIGHT...BRINGING
WITH IT SCATTERED LIGHT SNOW SHOWERS AMOUNTING TO NO MORE THAN AN
INCH OF ACCUMULATION AND STRONG NORTHWEST WIND IN ITS WAKE.
SURFACE OBS BEHIND THE FRONT THIS AFTERNOON ACROSS ND SHOWING
GUSTS IN EXCESS OF 30 KTS AND ALTHOUGH THIS AIR MASS WILL MODIFY
SOMEWHAT AS IT DROPS SOUTH...16.19Z RAP BRINGS A NOSE OF 35 TO 40
KTS AT 0.5 KM INTO THE WESTERN FORECAST AREA BY MONDAY MORNING.
WITH A DEEPENING WELL-MIXED BOUNDARY LAYER...THIS SHOULD RESULT IN
WIDESPREAD 20 TO 25 MPH NORTHWEST WINDS WITH FREQUENT GUSTS UP TO
35 MPH. THESE WINDS COMBINED WITH 2 TO 4 INCHES OF NEW SNOWFALL
FROM SUNDAY AND SUNDAY NIGHT ACROSS PORTIONS OF SOUTHEAST MN AND
NORTHEAST IA WILL RESULT IN AREAS OF BLOWING AND DRIFTING SNOW...
REDUCING VISIBILITY AT TIMES TO ONE HALF MILE OR LESS. WILL ISSUE
A WINTER WEATHER ADVISORY FOR BLOWING SNOW FROM 17.12Z TO 18.00Z
ACROSS THE WESTERN THIRD OF THE FORECAST AREA. THE COMBINATION OF
POOR VISIBILITY AND BLOWING SNOW WILL CREATE DIFFICULT TRAVEL
CONDITIONS FOR THE MORNING COMMUTE AND CONTINUING THROUGH MUCH OF
THE DAY.
OTHERWISE...MONDAY WILL BE MOSTLY CLOUDY AND COLD WITH AFTERNOON
HIGHS ONLY IN THE TEENS. SCATTERED LIGHT SNOW SHOWERS WILL RESULT
IN MINOR ADDITIONAL ACCUMULATIONS.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 158 PM CST SUN NOV 16 2014
850 HPA TEMPERATURES PLUNGE TO -18 C ACROSS THE FORECAST AREA BY
18.12Z (TUESDAY MORNING). THIS WILL RESULT IN THE COLDEST MORNING
SO FAR THIS SEASON. TEMPERATURES WILL FALL INTO THE SINGLE DIGITS
ABOVE ZERO WITH FAVORED COLD SPOTS DROPPING BELOW ZERO. COMBINED
WITH WESTERLY WINDS FROM 10 TO 15 MPH...WIND CHILL VALUES WILL BE
IN THE 10 TO 20 BELOW RANGE. THE REST OF TUESDAY WILL BE DRY AND
SHOULD SEE SOME PEAKS OF SUNSHINE LATE IN THE DAY AS MONDAY/S SNOW
MOVES OFF TO THE EAST. TEMPERATURES WILL TOP OUT IN THE MID TEENS.
A REINFORCING SHOT OF ARCTIC AIR WILL DROP SOUTH TUESDAY NIGHT
BEHIND THE NEXT COLD FRONT. MOST SNOW WILL FALL TO THE NORTH AND
EAST NEAREST THE BEST MID-LEVEL FORCING AND HIGHEST MOISTURE...
ALTHOUGH SOME SCATTERED LIGHT SNOW IS POSSIBLE ACROSS THE FORECAST
AREA WITH ACCUMULATIONS LESS THAN ONE INCH.
WEDNESDAY THROUGH FRIDAY WILL BE DRY AND UNSEASONABLY COLD. BROAD
SURFACE HIGH PRESSURE DRIFTS ACROSS THE UPPER MISSISSIPPI RIVER
VALLEY THROUGH THIS PERIOD...CENTERED ACROSS NORTHERN MO BY 12Z
FRIDAY. THE REGION REMAINS FULLY ENTRECHED WITHIN ARCTIC AIR MASS
THROUGH FRIDAY WITH DAILY HIGHS IN THE MID TEENS AND 20S AND LOWS
IN THE SINGLE DIGITS TO TEENS. DEPENDING ON CLOUD COVER...
THURSDAY NIGHT LOWS COULD RIVAL THOSE FROM TUESDAY MORNING.
MID-LEVEL THERMAL RIDGE FINALLY MAKES SOME EASTWARD PROGRESS BY
THE WEEKEND. WARM AIR ADVECTION REGIME SHOULD ALLOW TEMPERATURES
TO CLIMB BACK INTO THE 30S. HOWEVER...BOTH THE 16.12Z GFS AND
ECMWF SHOW THE NEXT STORM SYSTEM LIFTING NORTH FROM THE SOUTHERN
PLAINS OVER THE WEEKEND. THE ECMWF IS FARTHER WEST WITH ITS
PRECIP THAN THE GFS...SO FOR NOW WILL FOLLOW A BLENDED APPROACH
WITH 20 TO 30 POPS AND THE POTENTIAL FOR MIXED PRECIP GIVEN WARMER
TEMPERATURES ALOFT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1201 PM CST SUN NOV 16 2014
ALL EYES ON APPROACHING ARCTIC COLD FRONT WHICH IS CURRENTLY
MOVING THROUGH THE DAKOTAS. LOOK FOR THIS FRONT TO MAKE PASSAGE
THROUGH KRST AND KLSE THIS EVENING. THIS WILL SWING WINDS FROM THE
SOUTHWEST TO THE WEST/NORTHWEST. BRISK SOUTHWEST WINDS THIS
AFTERNOON AHEAD OF THE APPROACHING FRONT MAY PRODUCE SOME
DRIFTING OF THE SNOW AT KRST. STRONGER NORTHWEST WINDS BEHIND THE
FRONT WILL BEE SEEN MONDAY MORNING AS THE BRUNT OF THE ARCTIC AIR
PUSHES IN. NORTHWEST WINDS OF 15 TO 25KT WITH GUST NEARING 30KT
WILL LIKELY PRODUCE SOME BLOWING SNOW AT KRST. KLSE LOOKS TO BE A
BIT MORE SHELTERED BUT SOME DRIFTING MAY STILL BE NOTED.
OTHERWISE...PLAN ON VFR SKY CONDITIONS DETERIORATING INTO MVFR
BETWEEN 23-24Z WITH SOME FLURRIES. PLAN ON KRST TO SLIP INTO SOME
IFR VIS/CIGS BY 15Z AS BLSN BECOMES A BIT MORE WIDESPREAD.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...WINTER WEATHER ADVISORY FROM 6 AM TO 6 PM CST MONDAY FOR MNZ086-
087-094-095.
IA...WINTER WEATHER ADVISORY FROM 6 AM TO 6 PM CST MONDAY FOR IAZ008-
009-018-019.
&&
$$
SHORT TERM...ROGERS
LONG TERM...ROGERS
AVIATION...DAS