Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 01/11/16
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
900 AM MST SAT JAN 9 2016
.SYNOPSIS...
THE GRADUAL WARMING AND DRYING TREND WILL CONTINUE TODAY IN THE WAKE
OF THIS PAST WEEK`S RAINFALL. ANOTHER WEAK STORM SYSTEM WILL BRING A
VERY SLIGHT CHANCE OF SHOWERS TO THE AREA AGAIN TONIGHT AND SUNDAY.
NEXT WEEK WILL GENERALLY BE RAIN-FREE ACROSS THE DESERT SOUTHWEST AND
TEMPERATURES WILL REMAIN BELOW NORMAL.
&&
.DISCUSSION...
A RETURN TO DRIER AND SLIGHTLY WARMER CONDITIONS WILL CONTINUE TODAY
AS ATMOSPHERIC MOISTURE CONTINUES TO DRAW DOWN AND THE REGION BECOMES
SLIGHTLY REMOVED FROM THE UPPER STORM TRACK. SURFACE CONDITIONS THIS
MORNING ARE COOL...CALM AND SKIES ARE MOSTLY CLEAR. LINGERING
SURFACE MOISTURE AND STILL SATURATED FIELD/LANDSCAPES DID SUPPORT
SOME LIMITED MIST AND FOG DEVELOPMENT THIS MORNING. FOG/IR IMAGERY
NOT OVERLY ENTHUSIASTIC ABOUT THE COVERAGE HOWEVER SOME SOCIAL MEDIA
REPORTS AND SURFACE OBSERVATIONS AROUND THE AREA DO INDICATE SOME
MINIMAL VSBY RESTRICTIONS (SCOTTSDALE...GILA BEND AND AROUND THE
KOMATKE AREA AND GILA RIVER DRAINAGE TO BE SPECIFIC). ANY AREAS OF
PATCHY FOG/MIST DEVELOPMENT WILL SLOWLY DISSIPATE IN THE NEXT HOUR OR
TWO ONCE THE SUN GETS HIGHER IN THE SKY. DRY AND MOSTLY CLEAR
CONDITIONS IN STORE FOR TODAY AS WE SEE A BREAK IN BETWEEN THE ACTIVE
STORM SYSTEM TRAIN. NO UPDATES NEEDED TO THE FORECAST PACKAGE THIS
MORNING.
&&
.PREVIOUS DISCUSSION...
NORTHWESTERLY FLOW HAS BECOME ESTABLISHED ACROSS THE DESERT
SOUTHWEST IN THE WAKE OF THE LOW PRESSURE SYSTEM THAT BROUGHT THE
WIDESPREAD PRECIPITATION TO THE AREA. MAIN WEATHER CONCERN IN THE
SHORT-TERM IS THE POTENTIAL FOR FOG FORMATION. CROSSOVER TEMPERATURES
ARE GENERALLY IN THE UPPER 30S...SUGGESTING SOME POTENTIAL FOR
SATURATION NEAR THE SURFACE AROUND SUNRISE. HOWEVER...RECENT RUNS OF
THE HRRR ONLY INDICATE AN ISOLATED THREAT...PARTICULARLY ACROSS THE
LOWER GILA RIVER VALLEY. LATEST NCAR ENSEMBLE ALSO INDICATES VERY LOW
PROBABILITIES FOR RESTRICTED VSBYS. ANY FOG THAT DOES DEVELOP WILL
LIKELY BE PATCHY AND SHALLOW. IN TERMS OF SENSIBLE WEATHER...TODAY
WILL FINALLY BE A RAIN-FREE DAY BUT TEMPERATURES WILL REMAIN BELOW
NORMAL.
MODELS CONTINUE TO INDICATE THAT TWO WEAK VORT MAXES WILL AFFECT THE
AREA OVERNIGHT AND SUNDAY. THE FIRST SYSTEM WILL BRING AN INCREASE
IN CLOUDS AND A SLIGHT CHANCE OF SHOWERS TO SOUTHERN CA
TONIGHT...WITH THE HIGHEST POPS RELEGATED TO JTNP. THE SECOND
SYSTEM...A BIT FURTHER NORTH WILL PROVIDE SOME FORCING FOR ASCENT
SUNDAY...THOUGH ABOVE MEDIAN POPS ARE STILL ONLY AT OR BELOW 10
PERCENT FOR MUCH OF THE AREA. LOCAL HI-RES WRFS CONTINUE TO SUGGEST
THE BETTER THREAT WILL BE FURTHER TO THE NORTH AND EAST ACROSS THE
MOGOLLON RIM.
NEXT WEEK WILL BE LARGELY CHARACTERIZED BY THE PREVALENCE OF A LONG-
WAVE RIDGE ACROSS THE PACIFIC NORTHWEST AND INTERMOUNTAIN WEST. THE
PACIFIC WILL REMAIN ACTIVE WITH SEVERAL SHORT-WAVE TROUGHS IMPACTING
THE WEST. CONSIDERABLE SPREAD STILL REMAINS AMONG THE OPERATIONAL
GFS/ECMWF AND ASSOCIATED ENSEMBLE MEMBERS...HOWEVER THE GENERAL
CONSENSUS IS THAT NONE OF THESE SYSTEMS WILL BE ANOMALOUS OR
EXTREME...NOR WILL THEY HAVE AN IMPACT ON THE REGION UNTIL AT LEAST
FRIDAY OR SATURDAY. MEANWHILE...TEMPERATURES WILL LIKELY REMAIN A FEW
DEGREES BELOW NORMAL.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...
SKIES CLEARED EARLIER OVER MUCH OF THE AREA ASIDE FROM OVER THE
HIGHER TERRAIN. LOW LEVEL MOISTURE STILL REMAINS IN PLACE AND THUS
EXPECTING DAYTIME STRATOCU TO DEVELOP SOMETIME LATE THIS
MORNING...LASTING THROUGH THE AFTERNOON. CURRENT THINKING IS CLOUDS
WITH DECKS AROUND 6K FEET SHOULD REMAIN MOSTLY SCATTERED OVER THE
DESERTS AND BROKEN OVER THE HIGHER TERRAIN NORTH AND EAST OF PHOENIX.
WINDS WILL REMAIN LIGHT THROUGH THE PERIOD AND MOSTLY FOLLOW TYPICAL
DIURNAL DIRECTIONS.
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
SKIES TO REMAIN MOSTLY CLEAR ASIDE FROM SOME SCT-BKN CIRRUS LAYERS
PASSING OVER THE TERMINALS FROM TIME-TO-TIME THROUGH THE TAF PERIOD.
WINDS TO REMAIN ON THE LIGHT SIDE...8 KTS OR LESS...FAVORING A
NORTHERLY DIRECTION AT KBLH AND WESTERLY AT KIPL.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
MONDAY THROUGH FRIDAY...
AN OVERALL DRY BUT COOL WEEK IS IN STORE WITH SOME POTENTIAL FOR
RETURNING PRECIPITATION CHANCES BY THE END OF THE WEEK. HIGH
TEMPERATURES WILL REMAIN WELL BELOW NORMAL EACH DAY. LOW LEVEL
MOISTURE WILL REMAIN ELEVATED OVERALL WITH MINIMUM HUMIDITY VALUES
ABOVE 30 PERCENT EACH AFTERNOON. WINDS SHOULD BE LIGHT THROUGH THE
ENTIRE PERIOD.
&&
.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT BASED ON STANDARD OPERATING
PROCEDURES.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...NOLTE
PREVIOUS DISCUSSION...HIRSCH
AVIATION...KUHLMAN
FIRE WEATHER...KUHLMAN
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
502 AM MST SAT JAN 9 2016
.UPDATE...UPDATED AVIATION AND FIRE WEATHER DISCUSSIONS...
&&
.SYNOPSIS...
THE GRADUAL WARMING AND DRYING TREND WILL CONTINUE TODAY IN THE WAKE
OF THIS PAST WEEK`S RAINFALL. ANOTHER WEAK STORM SYSTEM WILL BRING A
VERY SLIGHT CHANCE OF SHOWERS TO THE AREA AGAIN TONIGHT AND SUNDAY.
NEXT WEEK WILL GENERALLY BE RAIN-FREE ACROSS THE DESERT SOUTHWEST AND
TEMPERATURES WILL REMAIN BELOW NORMAL.
&&
.DISCUSSION...
NORTHWESTERLY FLOW HAS BECOMES ESTABLISHED ACROSS THE DESERT
SOUTHWEST IN THE WAKE OF THE LOW PRESSURE SYSTEM THAT BROUGHT THE
WIDESPREAD PRECIPITATION TO THE AREA. MAIN WEATHER CONCERN IN THE
SHORT-TERM IS THE POTENTIAL FOR FOG FORMATION. CROSSOVER TEMPERATURES
ARE GENERALLY IN THE UPPER 30S...SUGGESTING SOME POTENTIAL FOR
SATURATION NEAR THE SURFACE AROUND SUNRISE. HOWEVER...RECENT RUNS OF
THE HRRR ONLY INDICATE AN ISOLATED THREAT...PARTICULARLY ACROSS THE
LOWER GILA RIVER VALLEY. LATEST NCAR ENSEMBLE ALSO INDICATES VERY LOW
PROBABILITIES FOR RESTRICTED VSBYS. ANY FOG THAT DOES DEVELOP WILL
LIKELY BE PATCHY AND SHALLOW. IN TERMS OF SENSIBLE WEATHER...TODAY
WILL FINALLY BE A RAIN-FREE DAY BUT TEMPERATURES WILL REMAIN BELOW
NORMAL.
MODELS CONTINUE TO INDICATE THAT TWO WEAK VORT MAXES WILL AFFECT THE
AREA OVERNIGHT AND SUNDAY. THE FIRST SYSTEM WILL BRING AN INCREASE
IN CLOUDS AND A SLIGHT CHANCE OF SHOWERS TO SOUTHERN CA
TONIGHT...WITH THE HIGHEST POPS RELEGATED TO JTNP. THE SECOND
SYSTEM...A BIT FURTHER NORTH WILL PROVIDE SOME FORCING FOR ASCENT
SUNDAY...THOUGH ABOVE MEDIAN POPS ARE STILL ONLY AT OR BELOW 10
PERCENT FOR MUCH OF THE AREA. LOCAL HI-RES WRFS CONTINUE TO SUGGEST
THE BETTER THREAT WILL BE FURTHER TO THE NORTH AND EAST ACROSS THE
MOGOLLON RIM.
NEXT WEEK WILL BE LARGELY CHARACTERIZED BY THE PREVALENCE OF A LONG-
WAVE RIDGE ACROSS THE PACIFIC NORTHWEST AND INTERMOUNTAIN WEST. THE
PACIFIC WILL REMAIN ACTIVE WITH SEVERAL SHORT-WAVE TROUGHS IMPACTING
THE WEST. CONSIDERABLE SPREAD STILL REMAINS AMONG THE OPERATIONAL
GFS/ECMWF AND ASSOCIATED ENSEMBLE MEMBERS...HOWEVER THE GENERAL
CONSENSUS IS THAT NONE OF THESE SYSTEMS WILL BE ANOMALOUS OR
EXTREME...NOR WILL THEY HAVE AN IMPACT ON THE REGION UNTIL AT LEAST
FRIDAY OR SATURDAY. MEANWHILE...TEMPERATURES WILL LIKELY REMAIN A FEW
DEGREES BELOW NORMAL.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...
SKIES CLEARED EARLIER OVER MUCH OF THE AREA ASIDE FROM OVER THE
HIGHER TERRAIN. LOW LEVEL MOISTURE STILL REMAINS IN PLACE AND THUS
EXPECTING DAYTIME STRATOCU TO DEVELOP SOMETIME LATE THIS
MORNING...LASTING THROUGH THE AFTERNOON. CURRENT THINKING IS CLOUDS
WITH DECKS AROUND 6K FEET SHOULD REMAIN MOSTLY SCATTERED OVER THE
DESERTS AND BROKEN OVER THE HIGHER TERRAIN NORTH AND EAST OF PHOENIX.
WINDS WILL REMAIN LIGHT THROUGH THE PERIOD AND MOSTLY FOLLOW TYPICAL
DIURNAL DIRECTIONS.
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
SKIES TO REMAIN MOSTLY CLEAR ASIDE FROM SOME SCT-BKN CIRRUS LAYERS
PASSING OVER THE TERMINALS FROM TIME-TO-TIME THROUGH THE TAF PERIOD.
WINDS TO REMAIN ON THE LIGHT SIDE...8 KTS OR LESS...FAVORING A
NORTHERLY DIRECTION AT KBLH AND WESTERLY AT KIPL.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
MONDAY THROUGH FRIDAY...
AN OVERALL DRY BUT COOL WEEK IS IN STORE WITH SOME POTENTIAL FOR
RETURNING PRECIPITATION CHANCES BY THE END OF THE WEEK. HIGH
TEMPERATURES WILL REMAIN WELL BELOW NORMAL EACH DAY. LOW LEVEL
MOISTURE WILL REMAIN ELEVATED OVERALL WITH MINIMUM HUMIDITY VALUES
ABOVE 30 PERCENT EACH AFTERNOON. WINDS SHOULD BE LIGHT THROUGH THE
ENTIRE PERIOD.
&&
.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT BASED ON STANDARD OPERATING
PROCEDURES.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...HIRSCH
AVIATION...KUHLMAN
FIRE WEATHER...KUHLMAN
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
327 AM MST SAT JAN 9 2016
.SYNOPSIS...
THE GRADUAL WARMING AND DRYING TREND WILL CONTINUE TODAY IN THE WAKE
OF THIS PAST WEEK`S RAINFALL. ANOTHER WEAK STORM SYSTEM WILL BRING A
VERY SLIGHT CHANCE OF SHOWERS TO THE AREA AGAIN TONIGHT AND SUNDAY.
NEXT WEEK WILL GENERALLY BE RAIN-FREE ACROSS THE DESERT SOUTHWEST AND
TEMPERATURES WILL REMAIN BELOW NORMAL.
&&
.DISCUSSION...
NORTHWESTERLY FLOW HAS BECOMES ESTABLISHED ACROSS THE DESERT
SOUTHWEST IN THE WAKE OF THE LOW PRESSURE SYSTEM THAT BROUGHT THE
WIDESPREAD PRECIPITATION TO THE AREA. MAIN WEATHER CONCERN IN THE
SHORT-TERM IS THE POTENTIAL FOR FOG FORMATION. CROSSOVER TEMPERATURES
ARE GENERALLY IN THE UPPER 30S...SUGGESTING SOME POTENTIAL FOR
SATURATION NEAR THE SURFACE AROUND SUNRISE. HOWEVER...RECENT RUNS OF
THE HRRR ONLY INDICATE AN ISOLATED THREAT...PARTICULARLY ACROSS THE
LOWER GILA RIVER VALLEY. LATEST NCAR ENSEMBLE ALSO INDICATES VERY LOW
PROBABILITIES FOR RESTRICTED VSBYS. ANY FOG THAT DOES DEVELOP WILL
LIKELY BE PATCHY AND SHALLOW. IN TERMS OF SENSIBLE WEATHER...TODAY
WILL FINALLY BE A RAIN-FREE DAY BUT TEMPERATURES WILL REMAIN BELOW
NORMAL.
MODELS CONTINUE TO INDICATE THAT TWO WEAK VORT MAXES WILL AFFECT THE
AREA OVERNIGHT AND SUNDAY. THE FIRST SYSTEM WILL BRING AN INCREASE
IN CLOUDS AND A SLIGHT CHANCE OF SHOWERS TO SOUTHERN CA
TONIGHT...WITH THE HIGHEST POPS RELEGATED TO JTNP. THE SECOND
SYSTEM...A BIT FURTHER NORTH WILL PROVIDE SOME FORCING FOR ASCENT
SUNDAY...THOUGH ABOVE MEDIAN POPS ARE STILL ONLY AT OR BELOW 10
PERCENT FOR MUCH OF THE AREA. LOCAL HI-RES WRFS CONTINUE TO SUGGEST
THE BETTER THREAT WILL BE FURTHER TO THE NORTH AND EAST ACROSS THE
MOGOLLON RIM.
NEXT WEEK WILL BE LARGELY CHARACTERIZED BY THE PREVALENCE OF A LONG-
WAVE RIDGE ACROSS THE PACIFIC NORTHWEST AND INTERMOUNTAIN WEST. THE
PACIFIC WILL REMAIN ACTIVE WITH SEVERAL SHORT-WAVE TROUGHS IMPACTING
THE WEST. CONSIDERABLE SPREAD STILL REMAINS AMONG THE OPERATIONAL
GFS/ECMWF AND ASSOCIATED ENSEMBLE MEMBERS...HOWEVER THE GENERAL
CONSENSUS IS THAT NONE OF THESE SYSTEMS WILL BE ANOMALOUS OR
EXTREME...NOR WILL THEY HAVE AN IMPACT ON THE REGION UNTIL AT LEAST
FRIDAY OR SATURDAY. MEANWHILE...TEMPERATURES WILL LIKELY REMAIN A FEW
DEGREES BELOW NORMAL.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL... L
CONSIDERABLE LOW/MID CLOUD PERSISTING ACROSS THE GREATER PHOENIX
AREA THIS EVENING...WITH CIGS DOWN AS LOW AS 4-5K FEET IN PLACES AND
WIDESPREAD CIGS 8-10K FEET. EXPECT THAT CIGS WILL START TO SCATTER
OUT LATER THIS EVENING AS SOMEWHAT DRIER AIR STARTS TO WORK IN FROM
THE NORTHWEST. STILL...LATEST HI-RES GUIDANCE SUGGESTS SHOWERS IN
THE AREA THRU 06Z...AND FORECAST SOUNDINGS KEEP RATHER SATURATED
LAYERS AROUND 5K FEET INTO THE MORNING ON SATURDAY. WILL ATTEMPT TO
SCATTER OUT THE LOWEST DECKS AFTER 06Z IN THE PHOENIX TAFS BUT
REALIZE THAT A STRAY CIG BELOW 6K FEET IS POSSIBLE PAST 12Z SAT.
SOME HIGH CLOUDS SHOULD BE MOVING INTO THE AREA FROM THE WEST LATER
TONIGHT AND INTO THE DAY SATURDAY AS WELL.
AS FAR AS THE POTENTIAL FOR FOG ON SAT MORNING IS CONCERNED...IT
APPEARS THAT FOG DEVELOPMENT IS UNLIKELY DUE TO THE FACT IT APPEARS
THAT ENOUGH DRY AIR WILL BE MIXING DOWN TO THE SFC TO PREVENT FOG
FORMATION...ALONG WITH THE FACT THAT INCREASING HIGH CLOUDINESS
SHOULD INHIBIT NIGHTTIME COOLING OF THE LOWER LEVELS OF THE
ATMOSPHERE. WINDS WILL BE REMAINING ON THE LIGHT SIDE...MAINLY 8 KTS
OR LESS...AND FAVOR USUAL DIURNAL TRENDS.
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
SKIES TO REMAIN MOSTLY CLEAR ASIDE FROM SOME SCT-BKN CIRRUS LAYERS
PASSING OVER THE TERMINALS FROM TIME-TO-TIME THROUGH THE TAF PERIOD.
WINDS TO REMAIN ON THE LIGHT SIDE...8 KTS OR LESS...FAVORING A
NORTHERLY DIRECTION AT KBLH AND WESTERLY AT KIPL.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
SUNDAY THROUGH THURSDAY...
A FAST MOVING WEATHER SYSTEM WILL BRING A CHANCE OF SHOWERS MAINLY
SATURDAY NIGHT INTO SUNDAY AS A WEAK DISTURBANCE PASSES THROUGH THE
REGION. COOL TEMPERATURES WILL PREVAIL WITH SOME GRADUAL WARMING
GOING INTO NEXT WEEK...BUT HIGHS WILL REMAIN BELOW NORMAL. HIGH
PRESSURE WILL SETTLE IN EARLY NEXT WEEK ALLOWING FOR GRADUAL DRYING
CONDITIONS. HUMIDITY WILL BE MUCH ABOVE AVERAGE WITH MINIMUM VALUES
NEAR 50 PERCENT INTO MONDAY WITH VALUES FALLING INTO THE 30S BY
WEDNESDAY. WINDS SHOULD BE LIGHT THROUGH THE ENTIRE PERIOD.
&&
.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT BASED ON STANDARD OPERATING
PROCEDURES.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...HIRSCH
AVIATION...PERCHA/CB
FIRE WEATHER...KUHLMAN
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
249 PM PST SAT JAN 9 2016
.SYNOPSIS...SCATTERED SHOWERS WILL GRADUALLY TAPER OFF THIS
EVENING. CLEARING AND COOL OVERNIGHT INTO SUNDAY MORNING. DRY ON
SUNDAY WITH BUILDING HIGH PRESSURE. NEXT FRONT APPROACHES MONDAY
BUT LOOKS TO WEAKEN WITH THE BEST CHANCE FOR LIGHT RAIN IN THE
NORTH BAY. ANOTHER STORM IS FORECAST TO ARRIVE LATE TUESDAY NIGHT
INTO WEDNESDAY WITH RAIN LIKELY.
&&
.DISCUSSION...AS OF 3:00 PM PST SATURDAY...SCATTERED SHOWERS
CONTINUE ACROSS OUR AREA. KMUX BEAM IS OVERSHOOTING QUITE A FEW OF
THEM BASED OFF OF GROUND TRUTH THAT WE ARE RECEIVING (PLEASE SEE
SFOPNSMTR FOR 24 HOUR TOTALS). IN GENERAL, COMMUNITIES HAVE PICKED
UP LESS THAN TWO TENTHS WITH SOME ISOLATED SPOTS IN THE HILLS
ABOVE 1/2". CLOUDS AND PRECIP HAVE PREVENTED TEMPS FROM WARMING UP
MUCH FROM THEIR OVERNIGHT LOWS. SHOULD END THE DAY WITH MOST SPOTS
IN THE 50S. LATEST RUN OF THE HRRR HAS RAINFALL SLOWLY ENDING
NORTH TO SOUTH LATE THIS AFTERNOON THROUGH THE EVENING. THIS GOES
ALONG WITH NAM/ECMWF/GFS THINKING. ADDITIONAL RAINFALL AMOUNTS
WILL BE LIGHT WITH THE POSSIBLE EXCEPTION OF THE SANTA LUCIAS.
THERE MORE THAN 1/4" COULD LOCALLY FALL. LOWS WILL GENERAL BE IN
THE 40S ONCE AGAIN.
A VERY WEAK SYSTEM WILL PASS THROUGH ON SUNDAY POSSIBLY BRINGING
A FEW SHOWERS TO OUR AREA -- PARTICULARLY THE SOUTHERN THIRD.
AMOUNTS WILL BE UNDER 1/10" IN ALMOST ALL CASES.
A SLIGHTLY STRONGER SYSTEM WILL THEN MOVE TO THE COAST AND BRING
ANOTHER ROUND OF RAIN BEGINNING SUNDAY NIGHT INTO MONDAY. CURRENT
TIMING BRINGS IT TO THE NORTH BY SUNDAY NIGHT THEN DOWN TO THE SF
BAY AREA MONDAY MORNING. RAIN WILL MOVE TO THE MONTEREY BAY REGION
BY LATE IN THE MORNING. RAINFALL AMOUNTS ARE FORECAST TO GENERALLY
BE 1/10" TO 1/4" WITH LOCALLY HIGHER AMOUNTS FOR THE NORTH BAY
MOUNTAINS. LIKELY THAT SANTA CLARA VALLEY DOWN THROUGH THE SALINAS
VALLEY WILL PICK UP EVEN LESS. RAIN WILL SWITCH BACK TO SHOWERS
LATER ON MONDAY.
AFTER ANOTHER BREAK FROM LATE MONDAY TO THE FIRST HALF OF TUESDAY,
ANOTHER SYSTEM WILL MOVE BACK TO OUR AREA. THIS ONE WILL LIKELY BE
THE STRONGEST OF THE WEEK WITH WIDESPREAD RAIN FORECAST LATE
TUESDAY NIGHT INTO WEDNESDAY. ALTHOUGH OVERALL DYNAMICS ARE NOT
NEARLY AS STRONG AS THE RECENT SYSTEMS, THIS SHOULD STILL BRING
1/4" TO 2/3" AMOUNTS WITH COASTAL RANGES IN THE 1-2" VALUES
(LOCALLY 3"+). RAIN MAY BE LOCALLY HEAVY AT TIMES AND PRE- FRONTAL
SOUTHERLY WINDS WILL GUST IN THE 20 TO 30 MPH IN MANY SPOTS. SOME
MODELS DO BRING THE MAIN BAND THROUGH IN THE MIDDLE OF THE DAY,
WHICH WOULD HELP TO MITIGATE RUSH HOUR ISSUES. WILL SEE WHAT THE
LATER MODELS SHOWS. RAIN WILL AGAIN SWITCH TO SHOWERS BY WEDNESDAY
EVENING OR NIGHT.
AFTER THAT POINT A PERIOD OF DRIER WEATHER IS FORECAST (THIS IS
SUPPORTED BY THE OPERATIONAL AND ENSEMBLE MODELS) AS A WEAK RIDGE
OF HIGH PRESSURE BUILDS INTO THE REGION. THIS WILL LIKELY HOLD
UNTIL AROUND SUNDAY WHEN A WEAK SYSTEM COULD BRING ANOTHER ROUND
OF LIGHT RAIN.
LONGER RANGE GUIDANCE INDICATES A RETURN TO ACTIVE WEATHER IN THE
10 TO 16 DAY RANGE. ABOVE NORMAL RAINFALL IS FORECAST.
&&
.AVIATION...AS OF 09:55 AM PST SATURDAY...A SURFACE FRONT
CONTINUES TO PASS OVER THE AREA THIS MORNING RESULTING IN
WIDESPREAD MVFR CIGS AND LIGHT RAIN. THIS FRONT APPEARS PRETTY
WEAK AND THE FORECAST MODEL SOUNDINGS ARE SHOWING CIGS SLOWLY
LOWERING BEHIND THE FRONT LATER THIS AFTERNOON...RATHER THAN THE
TYPICAL MIXING OUT BEHIND THE FRONT. OTHERWISE GENERALLY LIGHT
WINDS ARE EXPECTED AT MOST TERMINALS TODAY WITH THE EXCEPTION OF
KSNS.
VICINITY OF KSFO...MVFR CIGS ARE EXPECTED TO PREVAIL TODAY WITH
CIGS HOVERING AROUND BKN-OVC025-035. LIGHT RAIN IS EXPECTED TO
LINGER INTO THE EARLY AFTERNOON HOURS. GENERALLY LIGHT WINDS ARE
ANTICIPATED.
CONFIDENCE IS MODERATE.
SFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...VFR CONDITIONS ARE EXPECTED TO
PREVAIL TODAY WITH CIGS OVC040...OCCASIONAL BKN025 WILL BE
POSSIBLE WITH LIGHT SHOWERS THROUGH 2200Z. MVFR CIGS ARE EXPECTED
BY EARLY AFTERNOON WITH A LINGERING SHOWER IN THE VICINITY OF THE
TERMINAL. GENERALLY LIGHT WINDS AT KMRY WITH MODERATE EAST
SOUTHEASTERLY WINDS AT KSNS REACHING 18 KT WITH GUSTS TO 25 KT
INTO THE EARLY AFTERNOON HOURS.
CONFIDENCE IS MODERATE.
&&
.MARINE...AS OF 3:00 PM PST SATURDAY...WINDS WILL BECOME NORTH
NORTHWEST THIS EVENING BEHIND A DEPARTING COLD FRONT. WINDS ARE
EXPECTED TO INCREASE OUT OF THE SOUTH ONCE AGAIN SUNDAY EVENING AS
THE NEXT PACIFIC STORM SYSTEM APPROACHES THE COAST. A MODERATE
SIZED LONG PERIOD WESTERLY SWELL IS ANTICIPATED TO MOVE INTO THE
WATERS SUNDAY NIGHT...RESULTING IN LARGE BREAKING WAVES NEAR
OFFSHORE REEFS AND SAND BARS.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TNGT...SCA...PT REYES TO PIGEON PT 0-10 NM UNTIL 3 PM
SCA...PIGEON PT TO PT PINOS 0-10 NM UNTIL 3 PM
SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM UNTIL 3 PM
SCA...PIGEON PT TO PT PIEDRAS BLANCAS 10-60 NM UNTIL 3 PM
&&
$$
PUBLIC FORECAST: BELL
AVIATION: LARRY
MARINE: LARRY
VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO
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AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
955 AM PST SAT JAN 9 2016
.SYNOPSIS...AREAS OF LIGHT RAIN THIS MORNING WILL TURN TO
SCATTERED SHOWERS BY THE AFTERNOON. CLEARING AND COOL OVERNIGHT
INTO SUNDAY MORNING. DRY ON SUNDAY WITH BUILDING HIGH PRESSURE.
NEXT FRONT APPROACHES MONDAY BUT LOOKS TO WEAKEN WITH THE BEST
CHANCE FOR LIGHT RAIN IN THE NORTH BAY. ANOTHER STORM IS FORECAST
TO ARRIVE LATE TUESDAY NIGHT INTO WEDNESDAY WITH ANOTHER CHANCE OF
RAIN.
&&
.DISCUSSION...AS OF 8:30 AM PST SATURDAY...ALTHOUGH KMUX RADAR
SHOWS ONLY A FEW SPOTS WITH VERY LIGHT RETURNS, A RUN OF IRIS LAST
HOUR (SENT OUT AS SFOPNSMTR) SHOWS MANY LOCATIONS ACROSS OUR CWA
HAVE PICKED UP MEASURABLE PRECIPITATION. SONOMA SO FAR IS AHEAD OF
THE PACK WITH A HANDFUL ABOVE 1/3". OBVIOUSLY THE RADAR BEAM IS
OVERSHOOTING MUCH OF THE PRECIPITATION.
MADE A SMALL CHANGE TO THE FORECAST FOR THE REST OF TODAY BASED
OFF BOTH CURRENT PRECIP PLUS THE HRRR WHICH KEEPS SCATTERED
SHOWERS THROUGH ALL OF THE CWA UNTIL LATE IN THE AFTERNOON. HRRR
ALSO SHOWS SOME SCATTERED SHOWERS CONTINUING THROUGH THE EVENING
FOR THE SOUTHERN THIRD OF OUR REGION. HIGHER POP VALUES PLUS
UPDATED WEATHER AN QPF GRIDS HAVE BEEN SENT OUT.
12Z GFS CURRENTLY COMING IN IS CLOSE TO THE 0Z ECMWF FOR THE
STRONGEST SYSTEM NEXT WEEK (LATE TUESDAY INTO WEDNESDAY). LATEST
TRENDS ARE WETTER, SO UNLESS THE ECMWF TAKES AN UNEXPECTED TURN,
POPS WILL BE INCREASED FOR THAT PERIOD. OTHER SYSTEMS DURING THE
WEEK APPEAR TO BE VERY MINOR AT THIS TIME.
.PREVIOUS DISCUSSION...ONLY GETTING SOME LIGHT RAIN REPORTS THIS
MORNING WITH WEAK SYSTEM MOVING ONSHORE. RAIN TOTALS SO FAR
GENERALLY A FEW HUNDREDTHS TO AROUND A TENTH OF AN INCH. EXPECT
SCATTERED LIGHT RAIN OR SHOWERS TO CONTINUE THIS MORNING BUT THEN
BE ON THE DECREASE THIS AFTERNOON. IR SATELLITE SHOWS NO COLD AIR
ASSOCIATED ALOFT WITH THIS SYSTEM WITH WARMING CLOUD TOPS
SUGGESTING A WEAKENING UPPER LOW AS HIGH PRESSURE TRIES TO BUILD
ON THE BACKSIDE. LOOK FOR PARTLY CLOUDY SKIES AND SEASONABLY COOL
LOWS TONIGHT IN THE UPPER 30S AND 40S.
SUNDAY LOOKS LIKE THE NICER DAY OF THE WEEKEND WITH DRY WEATHER
FORECAST BUT PROBABLY ONLY FILTERED SUNSHINE WITH A COMBINATION OF
LINGERING LOW AND HIGH LEVEL CLOUD DECKS.
NEXT SYSTEM TRIES TO KNOCK DOWN THE RIDGE ON MONDAY WITH ANOTHER
CHANCE OF LIGHT RAIN...BUT MODEL TRENDS HAVE BEEN DRIER AND KEEP
THE BEST CHANCE OF RAIN NOW CONFINED NORTH OF THE GOLDEN GATE. IF
12Z RUNS KEEP THIS TREND WILL HAVE TO TRIM BACK POPS FOR THE SOUTH
BAY AND MONTEREY BAY REGION ON MONDAY. EITHER WAY ANY RAIN WITH
THE MONDAY SYSTEM LOOKS LIGHT EVEN FOR THE NORTH BAY.
MIDWEEK SYSTEM IS NOW TIMED SLIGHTLY FASTER TO ARRIVE LATER
TUESDAY EVENING INTO WEDNESDAY. ECMWF AND GFS STILL SHOWING A
LOW TO MODERATE STRENGTH SYSTEM MOVING ONSHORE...WITH THE GFS
SLIGHTLY MORE ROBUST IN TERMS OF QPF AND ASSOCIATED JET ENERGY AND
COLD ADVECTION ALOFT.
PATTERN REMAINS PROGRESSIVE WITH DRY CONDITIONS SUGGESTED FOR
THURSDAY AND FRIDAY AND POSSIBLY INTO SATURDAY. HOWEVER GENERAL
MODEL CONSENSUS FOR CONTINUED RAIN CHANCES BY NEXT MLK WEEKEND.
SIMILAR TO THIS WEEK EXPECT TO SEE SOME SIGNIFICANT RUN TO RUN
MODEL CHANGES IN THIS PROGRESSIVE AND DYNAMIC PATTERN. OVERALL
IDEA IS CONTINUED RAIN CHANCES BUT NO BIG STORMS ON THE
HORIZON.
&&
.AVIATION...AS OF 09:55 AM PST SATURDAY...A SURFACE FRONT
CONTINUES TO PASS OVER THE AREA THIS MORNING RESULTING IN
WIDESPREAD MVFR CIGS AND LIGHT RAIN. THIS FRONT APPEARS PRETTY
WEAK AND THE FORECAST MODEL SOUNDINGS ARE SHOWING CIGS SLOWLY
LOWERING BEHIND THE FRONT LATER THIS AFTERNOON...RATHER THAN THE
TYPICAL MIXING OUT BEHIND THE FRONT. OTHERWISE GENERALLY LIGHT
WINDS ARE EXPECTED AT MOST TERMINALS TODAY WITH THE EXCEPTION OF
KSNS.
VICINITY OF KSFO...MVFR CIGS ARE EXPECTED TO PREVAIL TODAY WITH
CIGS HOVERING AROUND BKN-OVC025-035. LIGHT RAIN IS EXPECTED TO
LINGER INTO THE EARLY AFTERNOON HOURS. GENERALLY LIGHT WINDS ARE
ANTICIPATED.
CONFIDENCE IS MODERATE.
SFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...VFR CONDITIONS ARE EXPECTED TO
PREVAIL TODAY WITH CIGS OVC040...OCCASIONAL BKN025 WILL BE
POSSIBLE WITH LIGHT SHOWERS THROUGH 2200Z. MVFR CIGS ARE EXPECTED
BY EARLY AFTERNOON WITH A LINGERING SHOWER IN THE VICINITY OF THE
TERMINAL. GENERALLY LIGHT WINDS AT KMRY WITH MODERATE EAST
SOUTHEASTERLY WINDS AT KSNS REACHING 18 KT WITH GUSTS TO 25 KT
INTO THE EARLY AFTERNOON HOURS.
CONFIDENCE IS MODERATE.
&&
.MARINE...AS OF 08:50 AM PST SATURDAY...A COLD FRONT IS PASSING
OVER THE COASTAL WATERS TODAY. EXPECT BREEZY SOUTH EASTERLY WINDS
THIS MORNING AHEAD OF THE FRONT WITH WINDS BECOMING WESTERLY LATER
TODAY AS THE FRONT MOVES ONSHORE. WINDS WILL INCREASE OUT OF THE
SOUTH ONCE AGAIN SUNDAY EVENING AS THE NEXT PACIFIC STORM SYSTEM
APPROACHES THE COAST.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...SCA...PT REYES TO PIGEON PT 0-10 NM UNTIL 3 PM
SCA...PIGEON PT TO PT PINOS 0-10 NM UNTIL 3 PM
SCA...PIGEON PT TO PT PIEDRAS BLANCAS 10-60 NM UNTIL 3 PM
SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM
&&
$$
PUBLIC FORECAST: BELL/RWW
AVIATION: LARRY
MARINE: LARRY
VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO
FOLLOW US ON FACEBOOK AND TWITTER AT:
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AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
851 AM PST SAT JAN 9 2016
.SYNOPSIS...AREAS OF LIGHT RAIN THIS MORNING WILL TURN TO
SCATTERED SHOWERS BY THE AFTERNOON. CLEARING AND COOL OVERNIGHT
INTO SUNDAY MORNING. DRY ON SUNDAY WITH BUILDING HIGH PRESSURE.
NEXT FRONT APPROACHES MONDAY BUT LOOKS TO WEAKEN WITH THE BEST
CHANCE FOR LIGHT RAIN IN THE NORTH BAY. ANOTHER STORM IS FORECAST
TO ARRIVE LATE TUESDAY NIGHT INTO WEDNESDAY WITH ANOTHER CHANCE OF
RAIN.
&&
.DISCUSSION...AS OF 8:30 AM PST SATURDAY...ALTHOUGH KMUX RADAR
SHOWS ONLY A FEW SPOTS WITH VERY LIGHT RETURNS, A RUN OF IRIS LAST
HOUR (SENT OUT AS SFOPNSMTR) SHOWS MANY LOCATIONS ACROSS OUR CWA
HAVE PICKED UP MEASURABLE PRECIPITATION. SONOMA SO FAR IS AHEAD OF
THE PACK WITH A HANDFUL ABOVE 1/3". OBVIOUSLY THE RADAR BEAM IS
OVERSHOOTING MUCH OF THE PRECIPITATION.
MADE A SMALL CHANGE TO THE FORECAST FOR THE REST OF TODAY BASED
OFF BOTH CURRENT PRECIP PLUS THE HRRR WHICH KEEPS SCATTERED
SHOWERS THROUGH ALL OF THE CWA UNTIL LATE IN THE AFTERNOON. HRRR
ALSO SHOWS SOME SCATTERED SHOWERS CONTINUING THROUGH THE EVENING
FOR THE SOUTHERN THIRD OF OUR REGION. HIGHER POP VALUES PLUS
UPDATED WEATHER AN QPF GRIDS HAVE BEEN SENT OUT.
12Z GFS CURRENTLY COMING IN IS CLOSE TO THE 0Z ECMWF FOR THE
STRONGEST SYSTEM NEXT WEEK (LATE TUESDAY INTO WEDNESDAY). LATEST
TRENDS ARE WETTER, SO UNLESS THE ECMWF TAKES AN UNEXPECTED TURN,
POPS WILL BE INCREASED FOR THAT PERIOD. OTHER SYSTEMS DURING THE
WEEK APPEAR TO BE VERY MINOR AT THIS TIME.
.PREVIOUS DISCUSSION...ONLY GETTING SOME LIGHT RAIN REPORTS THIS
MORNING WITH WEAK SYSTEM MOVING ONSHORE. RAIN TOTALS SO FAR
GENERALLY A FEW HUNDREDTHS TO AROUND A TENTH OF AN INCH. EXPECT
SCATTERED LIGHT RAIN OR SHOWERS TO CONTINUE THIS MORNING BUT THEN
BE ON THE DECREASE THIS AFTERNOON. IR SATELLITE SHOWS NO COLD AIR
ASSOCIATED ALOFT WITH THIS SYSTEM WITH WARMING CLOUD TOPS
SUGGESTING A WEAKENING UPPER LOW AS HIGH PRESSURE TRIES TO BUILD
ON THE BACKSIDE. LOOK FOR PARTLY CLOUDY SKIES AND SEASONABLY COOL
LOWS TONIGHT IN THE UPPER 30S AND 40S.
SUNDAY LOOKS LIKE THE NICER DAY OF THE WEEKEND WITH DRY WEATHER
FORECAST BUT PROBABLY ONLY FILTERED SUNSHINE WITH A COMBINATION OF
LINGERING LOW AND HIGH LEVEL CLOUD DECKS.
NEXT SYSTEM TRIES TO KNOCK DOWN THE RIDGE ON MONDAY WITH ANOTHER
CHANCE OF LIGHT RAIN...BUT MODEL TRENDS HAVE BEEN DRIER AND KEEP
THE BEST CHANCE OF RAIN NOW CONFINED NORTH OF THE GOLDEN GATE. IF
12Z RUNS KEEP THIS TREND WILL HAVE TO TRIM BACK POPS FOR THE SOUTH
BAY AND MONTEREY BAY REGION ON MONDAY. EITHER WAY ANY RAIN WITH
THE MONDAY SYSTEM LOOKS LIGHT EVEN FOR THE NORTH BAY.
MIDWEEK SYSTEM IS NOW TIMED SLIGHTLY FASTER TO ARRIVE LATER
TUESDAY EVENING INTO WEDNESDAY. ECMWF AND GFS STILL SHOWING A
LOW TO MODERATE STRENGTH SYSTEM MOVING ONSHORE...WITH THE GFS
SLIGHTLY MORE ROBUST IN TERMS OF QPF AND ASSOCIATED JET ENERGY AND
COLD ADVECTION ALOFT.
PATTERN REMAINS PROGRESSIVE WITH DRY CONDITIONS SUGGESTED FOR
THURSDAY AND FRIDAY AND POSSIBLY INTO SATURDAY. HOWEVER GENERAL
MODEL CONSENSUS FOR CONTINUED RAIN CHANCES BY NEXT MLK WEEKEND.
SIMILAR TO THIS WEEK EXPECT TO SEE SOME SIGNIFICANT RUN TO RUN
MODEL CHANGES IN THIS PROGRESSIVE AND DYNAMIC PATTERN. OVERALL
IDEA IS CONTINUED RAIN CHANCES BUT NO BIG STORMS ON THE
HORIZON.
&&
.AVIATION...AS OF 3:55 AM PST SATURDAY... SCATTERED TO WIDESPREAD
RAIN SHOWERS ACROSS THE REGION THIS MORNING BRINGING -SHRA TO MOST
TAF SITES. CIGS ARE GRADUALLY DESCENDING INTO THE UPPER MVFR
RANGE... IE 2500-4000 FT AGL AS FRONT PUSHES INLAND. WINDS WILL
GENERALLY BE LIGHT SOUTHEAST THROUGH THE FORECAST PERIOD. RAIN
SHOWERS WILL BECOME ISOLATED TO SCATTERED AFTER 00Z AND END FOR
MOST AREAS BY 03Z.
VICINITY OF KSFO... -SHRA THROUGH 20Z SAT... THEN LINGERING VCSH
THROUGH 00-03Z SUN. WIND GENERALLY LIGHT AND SOUTHEASTERLY.
INTERMITTENT VFR/MVFR CIGS.
SFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS... -SHRA THROUGH 20Z SAT... THEN
LINGERING VCSH THROUGH 00-03Z SUN. WINDS GENERALLY SOUTHEASTERLY
AND LIGHT EXCEPT IN THE SALINAS VALLEY... WHERE BREEZY SOUTHEAST
WINDS WILL PERSIST THROUGH 21Z. INTERMITTENT VFR/MVFR CIGS.
&&
.MARINE...AS OF 08:50 AM PST SATURDAY...A COLD FRONT IS PASSING
OVER THE COASTAL WATERS TODAY. EXPECT BREEZY SOUTH EASTERLY WINDS
THIS MORNING AHEAD OF THE FRONT WITH WINDS BECOMING WESTERLY LATER
TODAY AS THE FRONT MOVES ONSHORE. WINDS WILL INCREASE OUT OF THE
SOUTH ONCE AGAIN SUNDAY EVENING AS THE NEXT PACIFIC STORM SYSTEM
APPROACHES THE COAST.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...SCA...PT REYES TO PIGEON PT 0-10 NM UNTIL 3 PM
SCA...PIGEON PT TO PT PINOS 0-10 NM UNTIL 3 PM
SCA...PIGEON PT TO PT PIEDRAS BLANCAS 10-60 NM UNTIL 3 PM
SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM
&&
$$
PUBLIC FORECAST: BELL/RWW
AVIATION: DRP
MARINE: LARRY
VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO
FOLLOW US ON FACEBOOK AND TWITTER AT:
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AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
831 AM PST SAT JAN 9 2016
.SYNOPSIS...AREAS OF LIGHT RAIN THIS MORNING WILL TURN TO
SCATTERED SHOWERS BY THE AFTERNOON. CLEARING AND COOL OVERNIGHT
INTO SUNDAY MORNING. DRY ON SUNDAY WITH BUILDING HIGH PRESSURE.
NEXT FRONT APPROACHES MONDAY BUT LOOKS TO WEAKEN WITH THE BEST
CHANCE FOR LIGHT RAIN IN THE NORTH BAY. ANOTHER STORM IS FORECAST
TO ARRIVE LATE TUESDAY NIGHT INTO WEDNESDAY WITH ANOTHER CHANCE OF
RAIN.
&&
.DISCUSSION...AS OF 8:30 AM PST SATURDAY...ALTHOUGH KMUX RADAR
SHOWS ONLY A FEW SPOTS WITH VERY LIGHT RETURNS, A RUN OF IRIS LAST
HOUR (SENT OUT AS SFOPNSMTR) SHOWS MANY LOCATIONS ACROSS OUR CWA
HAVE PICKED UP MEASURABLE PRECIPITATION. SONOMA SO FAR IS AHEAD OF
THE PACK WITH A HANDFUL ABOVE 1/3". OBVIOUSLY THE RADAR BEAM IS
OVERSHOOTING MUCH OF THE PRECIPITATION.
MADE A SMALL CHANGE TO THE FORECAST FOR THE REST OF TODAY BASED
OFF BOTH CURRENT PRECIP PLUS THE HRRR WHICH KEEPS SCATTERED
SHOWERS THROUGH ALL OF THE CWA UNTIL LATE IN THE AFTERNOON. HRRR
ALSO SHOWS SOME SCATTERED SHOWERS CONTINUING THROUGH THE EVENING
FOR THE SOUTHERN THIRD OF OUR REGION. HIGHER POP VALUES PLUS
UPDATED WEATHER AN QPF GRIDS HAVE BEEN SENT OUT.
12Z GFS CURRENTLY COMING IN IS CLOSE TO THE 0Z ECMWF FOR THE
STRONGEST SYSTEM NEXT WEEK (LATE TUESDAY INTO WEDNESDAY). LATEST
TRENDS ARE WETTER, SO UNLESS THE ECMWF TAKES AN UNEXPECTED TURN,
POPS WILL BE INCREASED FOR THAT PERIOD. OTHER SYSTEMS DURING THE
WEEK APPEAR TO BE VERY MINOR AT THIS TIME.
.PREVIOUS DISCUSSION...ONLY GETTING SOME LIGHT RAIN REPORTS THIS
MORNING WITH WEAK SYSTEM MOVING ONSHORE. RAIN TOTALS SO FAR
GENERALLY A FEW HUNDREDTHS TO AROUND A TENTH OF AN INCH. EXPECT
SCATTERED LIGHT RAIN OR SHOWERS TO CONTINUE THIS MORNING BUT THEN
BE ON THE DECREASE THIS AFTERNOON. IR SATELLITE SHOWS NO COLD AIR
ASSOCIATED ALOFT WITH THIS SYSTEM WITH WARMING CLOUD TOPS
SUGGESTING A WEAKENING UPPER LOW AS HIGH PRESSURE TRIES TO BUILD
ON THE BACKSIDE. LOOK FOR PARTLY CLOUDY SKIES AND SEASONABLY COOL
LOWS TONIGHT IN THE UPPER 30S AND 40S.
SUNDAY LOOKS LIKE THE NICER DAY OF THE WEEKEND WITH DRY WEATHER
FORECAST BUT PROBABLY ONLY FILTERED SUNSHINE WITH A COMBINATION OF
LINGERING LOW AND HIGH LEVEL CLOUD DECKS.
NEXT SYSTEM TRIES TO KNOCK DOWN THE RIDGE ON MONDAY WITH ANOTHER
CHANCE OF LIGHT RAIN...BUT MODEL TRENDS HAVE BEEN DRIER AND KEEP
THE BEST CHANCE OF RAIN NOW CONFINED NORTH OF THE GOLDEN GATE. IF
12Z RUNS KEEP THIS TREND WILL HAVE TO TRIM BACK POPS FOR THE SOUTH
BAY AND MONTEREY BAY REGION ON MONDAY. EITHER WAY ANY RAIN WITH
THE MONDAY SYSTEM LOOKS LIGHT EVEN FOR THE NORTH BAY.
MIDWEEK SYSTEM IS NOW TIMED SLIGHTLY FASTER TO ARRIVE LATER
TUESDAY EVENING INTO WEDNESDAY. ECMWF AND GFS STILL SHOWING A
LOW TO MODERATE STRENGTH SYSTEM MOVING ONSHORE...WITH THE GFS
SLIGHTLY MORE ROBUST IN TERMS OF QPF AND ASSOCIATED JET ENERGY AND
COLD ADVECTION ALOFT.
PATTERN REMAINS PROGRESSIVE WITH DRY CONDITIONS SUGGESTED FOR
THURSDAY AND FRIDAY AND POSSIBLY INTO SATURDAY. HOWEVER GENERAL
MODEL CONSENSUS FOR CONTINUED RAIN CHANCES BY NEXT MLK WEEKEND.
SIMILAR TO THIS WEEK EXPECT TO SEE SOME SIGNIFICANT RUN TO RUN
MODEL CHANGES IN THIS PROGRESSIVE AND DYNAMIC PATTERN. OVERALL
IDEA IS CONTINUED RAIN CHANCES BUT NO BIG STORMS ON THE
HORIZON.
&&
.AVIATION...AS OF 3:55 AM PST SATURDAY... SCATTERED TO WIDESPREAD
RAIN SHOWERS ACROSS THE REGION THIS MORNING BRINGING -SHRA TO MOST
TAF SITES. CIGS ARE GRADUALLY DESCENDING INTO THE UPPER MVFR
RANGE... IE 2500-4000 FT AGL AS FRONT PUSHES INLAND. WINDS WILL
GENERALLY BE LIGHT SOUTHEAST THROUGH THE FORECAST PERIOD. RAIN
SHOWERS WILL BECOME ISOLATED TO SCATTERED AFTER 00Z AND END FOR
MOST AREAS BY 03Z.
VICINITY OF KSFO... -SHRA THROUGH 20Z SAT... THEN LINGERING VCSH
THROUGH 00-03Z SUN. WIND GENERALLY LIGHT AND SOUTHEASTERLY.
INTERMITTENT VFR/MVFR CIGS.
SFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS... -SHRA THROUGH 20Z SAT... THEN
LINGERING VCSH THROUGH 00-03Z SUN. WINDS GENERALLY SOUTHEASTERLY
AND LIGHT EXCEPT IN THE SALINAS VALLEY... WHERE BREEZY SOUTHEAST
WINDS WILL PERSIST THROUGH 21Z. INTERMITTENT VFR/MVFR CIGS.
&&
.MARINE...AS OF 08:18 AM PST SATURDAY...BREEZY SOUTHERLY WINDS
EARLY THIS MORNING WILL SHIFT TO THE WEST AND WEAKEN LATER TODAY.
WINDS INCREASE LATE THIS WEEKEND AHEAD OF THE NEXT PACIFIC STORM
SYSTEM. MODERATE WESTERLY SWELL WILL CONTINUE TO DIMINISH TONIGHT.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...SCA...PT REYES TO PIGEON PT 0-10 NM UNTIL 3 PM
SCA...PIGEON PT TO PT PINOS 0-10 NM UNTIL 3 PM
SCA...PIGEON PT TO PT PIEDRAS BLANCAS 10-60 NM UNTIL 3 PM
SCA...PT ARENA TO PT REYES 0-10 NM UNTIL 9 AM
SCA...PT ARENA TO PIGEON PT 10-60 NM UNTIL 9 AM
SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM
&&
$$
PUBLIC FORECAST: BELL/RWW
AVIATION: DRP
MARINE: DRP
VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO
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AREA FORECAST DISCUSSION
NWS PUEBLO CO
413 AM MST SAT JAN 9 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 356 AM MST SAT JAN 9 2016
CURRENTLY...
GENERALLY CLOUDY SKIES WITH AREAS OF FOG PREVAIL ACROSS THE FCST
AREA. A FEW SNOW SHOWERS WERE STILL NOTED OVER THE PLAINS...AND SNOW
SHOWERS WERE OCCURRING ACROSS THE CENTRAL MTNS. TEMPS WERE STILL
REASONABLY MILD OVER THE REGION GIVEN THE CLOUD COVER...WITH TEENS
AND 20S OVER THE PLAINS...TEENS AND SINGLE DIGITS VALLEYS...AND
SINGLE DIGITS MTNS.
TODAY...
A COLD DAY IS EXPECTED ACROSS THE REGION. WE SHOULD SEE CLOUDS
DECREASE SOMEWHAT OVER THE AREA BUT WE WILL STILL SEE QUITE A BIT OF
CLOUDS THIS AFTERNOON OVER MOST OF THE REGION AS INDICATED BY POINT
SOUNDINGS. SNOW SHOWERS WILL CONTINUE ON THE CENTRAL MTNS...WITH
LIGHT ACCUMS POSSIBLE. GIVEN THE SNOW THAT FELL OVER THE PLAINS AND
CLOUD COVER...TEMPS WILL STRUGGLE TO REACH THE FREEZING MARK OVER
THE LOWER ELEVATIONS THIS AFTERNOON.
TONIGHT...
COLD. SAN LUIS VALLEY WILL LIKELY WILL BE COLDEST WITH MIN TEMPS
EXPECTED IN THE NEGATIVE SINGLE DIGITS . OVER THE PLAINS POSITIVE
SINGLE DIGITS ARE LIKELY. MTNS WILL RANGE FROM ZERO TO NEGATIVE 10F.
IT WILL REMAIN DRY. SOUNDINGS SHOW THE LOW LVLS DRYING OUT OVER THE
PLAINS DURING THE EARLY MORNING HOURS...AND THIS MAY LIMIT FOG
POTENTIAL...ALTHOUGH I CANNOT RULE IT OUT COMPLETELY. SOUNDING
PROFILES INDICATE THE SAN LUIS VALLEY MAY CLOUD UP/FOG UP LATER
TONIGHT AND HAVE ACCOUNTED FOR THIS IN THE NDFD.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 356 AM MST SAT JAN 9 2016
NOT MUCH CHANGE TO THE FORECAST THINKING THROUGH MUCH OF THE
EXTENDED PERIOD. THERE IS SOME UNCERTAINTY LATE IN THE WORK WEEK
WITH AN INCOMING UPPER DISTURBANCE BETWEEN THE GFS AND ECMWF WITH
HIGHER ENSEMBLE SPREADS.
SUNDAY...AN UPPER DISTURBANCE IN NORTHWEST FLOW WILL TRACK SOUTH
ACROSS WESTERN COLORADO. THIS WILL BRING PERIODS OF LIGHT SNOW TO
THE CONTINENTAL DIVIDE THROUGH SUNDAY EVENING BEFORE COMING TO AN
END DURING THE OVERNIGHT HOURS. AN INCH OR TWO OF ACCUMULATION IS
POSSIBLE...ESPECIALLY ON NORTHWEST FACING SLOPES. COLD AND DRY
CONDITIONS WILL PREVAIL ACROSS THE PLAINS WITH HIGHS IN THE 30S.
MONDAY THROUGH WEDNESDAY...NORTHWEST FLOW WILL GIVE WAY TO HIGH
PRESSURE ALOFT MOVING ACROSS COLORADO. EXPECT DRY CONDITIONS
ACROSS THE REGION THROUGH THIS PERIOD. TEMPERATURES WILL SLOWLY
WARM WITH MID TO UPPER 40S FOR THE PLAINS BY WEDNESDAY.
THURSDAY AND FRIDAY...MODELS DIVERGE HEADING INTO THE LATE WORK
WEEK. THE GFS SHIFTS THE UPPER RIDGE EAST INTO THE CENTRAL PLAINS
AND BRINGS A STRONG TROUGH ACROSS THE DESERT SOUTHWEST. PLENTY OF
MOISTURE AND SOUTHWEST FLOW ON THURSDAY WOULD SPREAD SNOW INTO THE
CONTINENTAL DIVIDE...THEN SPREADING EAST ACROSS THE PLAINS BY
FRIDAY BEHIND A COLD FRONT. DECENT MOUNTAIN SNOWS WOULD BE
POSSIBLE WITH LIGHT SNOWS ACROSS THE PLAINS BASED ON THE GFS
SOLUTION. THE ECMWF IS MUCH SLOWER AND FURTHER SOUTH WITH THE
STORM SYSTEM. IT DOES NOT BRING THE SYSTEM ACROSS THE AREA UNTIL
FRIDAY INTO THE WEEKEND...WITH THE STORM TRACK NEAR THE MEXICO
BORDER. THIS WOULD KEEP MOST OF THE PRECIPITATION TO THE SOUTH
WITH LIMITED COVERAGE ACROSS SOUTHERN COLORADO. ENSEMBLE SPREADS
ARE HIGH...SO CONFIDENCE IN STORM TRACK AND PRECIPITATION ARE LOW
AT THIS TIME FOR THURSDAY AND FRIDAY. MOZLEY
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 356 AM MST SAT JAN 9 2016
KCOS...LIFR CONDITIONS NOTED AT KCOS AT 11 UTC THIS MORNING AS
DENSE FOG WAS OVER THE AIRPORT. THESE CONDITIONS WILL LIKELY EXIST
UNTIL MID MORNING...ALTHOUGH IFR/MVFR MAY EXIST THROUGH MOST IF
NOT ALL OF THE DAY. IT SHOULD REMAIN DRY. CONDITIONS ARE FCST TO
DRY OUT THIS EVENING WITH VFR CONDITIONS RETURNING. PLAN TO
CLOSELY MONITOR HRRR DATA FOR THE 12 UTC TAF FCST.
KPUB...MVFR CIGS NOTED AT 11 UTC. EXPECT CIGS AND VIS TO COME
DOWN SOMEWHAT THIS MORNING. LOWER CLOUDS WILL LIKELY REMAIN OVER
THE TAF SITE INTO THE AFTERNOON BUT MAY CIGS WILL PROBABLY BE
ABOVE MVFR CRITERIA. CONDITIONS SHOULD DRY OUT LATER TONIGHT WITH
VFR CONDITIONS RETURNING.
KALS...MID CLOUD DECK KEEPING VIS ABOVE P6SM AND PREVENTING FOG
FORMATION. DO NOT KNOW IF THIS WILL LAST THROUGH THE MORNING AS IF
IT CLEARS OUT ANY FOG WILL FORM AND CIGS WILL LOWER. HI RES
GUIDANCE INDICATES LOW CIGS/FOG SHOULD DEVELOP OVER KALS THIS
MORNING. WILL CONTINUE TO MONITOR. FOR TONIGHT...LOW CLOUDS
EXPECTED FOR THE SAN LUIS VALLEY.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...HODANISH
LONG TERM...MOZLEY
AVIATION...HODANISH
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
1047 AM EST SAT JAN 9 2016
.SYNOPSIS...
HIGH PRESSURE FROM EASTERN CANADA DOWN TO THE MID ATLANTIC STATES
WEAKENS LATE TODAY. LOW PRESSURE IN THE OHIO VALLEY THIS EVENING
INTENSIFIES RAPIDLY IS IT CROSSES PENNSYLVANIA AND NEW YORK STATE
SUNDAY. IT DRAWS A STRONG WARM FRONT NORTHWARD THROUGH OUR AREA
SUNDAY MORNING, THEN A STRONG COLD FRONT PASSES OFF THE COAST
SUNDAY AFTERNOON. HIGH PRESSURE BUILDS TO OUR SOUTH LATE MONDAY.
GREAT LAKES LOW PRESSURE TUESDAY SENDS A STRONG COLD FRONT ACROSS
THE MID ATLANTIC STATES TUESDAY EVENING. THAT LOW REFORMS ALONG
COASTAL NEW ENGLAND AND INTENSIFIES RAPIDLY ON WEDNESDAY. HIGH
PRESSURE BUILDS TO OUR SOUTH ON THURSDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
EARLIER THIS MORNING, THE WINTER WEATHER ADVISORY WAS ALLOWED TO
EXPIRE AS PRECIP WAS LIMITED OVER THE REMAINING ADVISORY AREA AND
TEMPERATURES WERE ABOVE FREEZING, EXCEPT ACROSS THE HIGHEST
TERRAIN LOCATIONS. AN UPWARD TREND HAS CONTINUED WITH HOURLY
TEMPERATURES SINCE THAT TIME, AND TEMPS ARE GENERALLY RUNNING IN
THE MID TO UPPER 30S WITH A LITTLE LIGHT RAIN/DRIZZLE ACROSS
NORTHWEST NJ AND THE POCONOS. IN FACT, WE ACTUALLY EXTENDED THE
COVERAGE AND LOW POPS FOR LIGHT RAIN ACROSS MUCH OF NJ THROUGH
THE REMAINDER OF THE MORNING TO EARLY AFTERNOON, BASED ON LATEST
RADAR TRENDS. OTHERWISE, SOME MINOR ADJUSTMENTS WERE MADE TO
HOURLY TEMPS THROUGH THE REST OF THE MORNING FOR THE REMAINDER OF
THE CWA, WITH TEMPS RISING INTO THE MID/UPPER 40S AND EVEN SOME
50S ACROSS SOUTHERN NJ AND THE SOUTHERN DELMARVA.
OTHERWISE, TODAY LOOKS TO BE A CLOUDY DAY ACROSS THE REGION AS A
WARM FRONTAL BOUNDARY LIFTS NORTHWARD INTO NEW ENGLAND AND LOW
PRESSURE DEVELOPS OFF THE SOUTHEAST UNITED STATES COASTLINE. THIS
WILL RESULT IN WARMER AND MOISTER AIR BEING ADVECTED INTO THE
REGION WITH EASTERLY WINDS FROM 5-10 MPH. DAYTIME TEMPERATURES
SHOULD RISE TO AROUND 50 FOR MOST LOCATIONS WITH THE POCONOS
STRUGGLING TO GET OUT OF THE UPPER 30S. BOTH THE HRRR AND RAP
MESOSCALE MODELS ARE TRYING TO SPIT OUT A BRIEF SHOWER OR TWO
TODAY, SO HAVE LOW OR SLIGHT CHANCE POPS ACROSS THE REGION TODAY.
THE MAJORITY OF THE REGION WILL STAY DRY THROUGH THE DAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SUNDAY/...
THE LOW PRESSURE IN THE SOUTHEAST UNITED STATES WILL CONTINUE TO
MOVE QUICKLY NORTHWARD TONIGHT REACHING OUR AREA BY SUNDAY MORNING
WITH A WARM FRONT EXTENDING EAST OF THE LOW PRESSURE CENTER. AN
AGGRESSIVE LLJ MODELED NEAR 60 KNOTS WILL CONTINUE TO SEND NORTHWARD
WARMER AND MOIST AIR INTO THE REGION. MOISTURE LIFTING OVER THE WARM
FRONT WILL LEAD TO WIDESPREAD RAIN BREAKING OUT TO OUR SOUTH LATE
SATURDAY. THE RAIN WILL INCREASE IN COVERAGE AND INTENSITY AS THE
NIGHT GOES ON WITH ALL LOCATIONS SEEING A STEADY RAIN BY SUNDAY
MORNING. TEMPERATURES WILL ACTUALLY RISE OVERNIGHT AND THE FORECAST
DOES GO WARMER WITH THE TEMPERATURES OVERNIGHT THAN WHAT THE MAV/MET
GUIDANCE SUGGESTS DUE TO THE LLJ INFLUENCE. AROUND HALF AN INCH OF
RAIN SHOULD FALL TONIGHT WITH ADDITIONAL RAIN ON SUNDAY. SOME OF THE
HEAVIER INTERVALS OF RAIN MAY CAUSE SOME PONDING OF WATER ON
ROADWAYS.
WINDS WILL INCREASE AS WELL, THE GFS, ECMWF AND NAM ALL
SUGGEST WINDS AT 925 MB REACH AT LEAST 50 MPH BY SUNDAY MORNING SE
OF PHILADELPHIA. WHILE THE STRONGEST WINDS WILL LIKELY BE ON SUNDAY,
THE FORECAST DOES GO STRONGER THAN GUIDANCE WITH THE WINDS AFTER
MIDNIGHT TONIGHT. SOME EAST TO SOUTHEAST WIND GUSTS AROUND 25 MPH
ARE POSSIBLE BY SUNDAY MORNING.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
500 MB: A NEGATIVE TILT SHORT WAVE RIPS NEWD THROUGH THE NORTHEAST
SUNDAY FOLLOWED BY THE DEVELOPMENT OF A FULL LATITUDE TROUGH ALONG
THE EAST COAST NEXT TUESDAY AND THEN WESTERLY FLOW DEVELOPS BY NEXT
THURSDAY BEFORE A NEW TROUGH FORMS IN THE CENTRAL USA NEXT WEEKEND.
TEMPERATURES: AFTER RECORD OR NEAR RECORD WARMTH SUNDAY AND MAXIMUM
TEMPERATURES NEARLY 25 DEGREES ABOVE NORMAL, CALENDAR DAY AVERAGES
WILL COOL TO NEAR NORMAL MONDAY AND TUESDAY, THEN SLIP A FEW DEGREES
BELOW NORMAL WEDNESDAY. THEREAFTER THERE IS SOME UNCERTAINTY...
BUT OVERALL NEAR OR SLIGHTLY BELOW NORMAL THURSDAY AND FRIDAY.
FORECAST BASIS: UNLESS OTHERWISE NOTED, A 50 50 BLEND 00Z/9 GFS/NAM
MOS GUIDANCE SUNDAY-SUNDAY NIGHT, THEREAFTER THE 00Z/9 GFS MEX MOS
MONDAY AND TUESDAY, THEN FOR TUESDAY NIGHT-FRIDAY GENERALLY THE
06Z/9 SUPERBLEND WHICH INCLUDES 00Z/9 GFS MEX GUIDANCE AND WPC
GUIDANCE.
THE DAILIES...
SUNDAY...A STORMY MORNING WITH AN OPPORTUNITY FOR A STRONG TSTM
IN STRONG SE INFLOW WITH INSTABILITY, ESPECIALLY ALOFT WHERE SWI
WILL BE BRIEFLY NEAR -2C, TT IN THE LOWER 50S AND RAPIDLY FALLING
SFC PRES. THIS COULD MEAN ISOLATED WIND GUSTS 40-50 MPH, ESPECIALLY
DELMARVA AND COASTAL NJ.
WE MAY EVENTUALLY NEED A WIND ADVY FOR THE NEAREST 5 MILES OF THE NJ
COAST IN THE 10Z-15Z TIME FRAME AND THIS IS WHERE I`VE GREATEST
CONFIDENCE ON VERIFYING NON CONVECTIVE 46 MPH SE WIND GUSTS.
BRIEF POOR DRAINAGE STREET FLOODING IN THE MORNING BUT OTRW NO
STREAM FLOODING EXPECTED.
TIDES WILL APPROACH MINOR ADVISORY STAGE IN THE 12Z-14Z TIME FRAME
BUT NO ADVISORY ATTM.
A WSHIFT TO WSW IN THE AFTERNOON WITH RECORD OR NEAR RECORD WARMTH
DURING MIDDAY BEGINNING TO BE SWEPT SEAWARD AND MAYBE ONE LAST
BAND OF SHOWERS PASSING EASTWARD AS A COLD FRONT MOVES THROUGH OUR
FORECAST AREA.
SUNDAY NIGHT...P/C, WINDY AND TURNING COLDER. GUSTY WEST WINDS 30-40
MPH. STRONG PRESSURE RISES DURING THE EVENING ACCOMPANIES THE INFLUX
OF COLDER DRIER AIR. SMALL CHC OF FLURRIES IN THE POCONOS.
MONDAY...DRY AND BREEZY. WESTERLY WIND GUSTS TO 25 MPH. .
TUESDAY...CHANCE OF SNOW SHOWERS OR FLURRIES IN THE DESTABILIZING
AIRMASS AS A STRONG TROUGH DEVELOPS ALONG THE EAST COAST. GUSTY
SOUTHWEST WINDS 20 TO 25 MPH SHIFTING TO WEST AT NIGHT WITH GUSTS
20 TO 30 MPH.
WEDNESDAY...WINDY AND COLD. DRY WITH EXCEPTION ALONG AND NORTH OF
I-78 WHERE THERE ARE MODEL INDICATIONS OF STEEP LAPSE RATES AND
POSSIBLE FLURRIES. WESTERLY WINDS WILL BE GUSTING 30 TO POSSIBLY
40 MPH.
THURSDAY...DIMINISHING WIND AND NOT QUITE AS COLD.
FRIDAY...UNCERTAINTY. FOR NOW, FORECASTING QUIET WEATHER (NOT THE
OUTLIER 00Z/9 ECMWF OPERATIONAL SOLUTION)
&&
.AVIATION /16Z SATURDAY THROUGH WEDNESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
MOST LOCATIONS ARE CURRENTLY VARYING BETWEEN MVFR AND VFR
CEILINGS, WITH KRDG AND KABE MAINLY SEEING MVFR TO IFR CEILINGS.
THIS WILL LIKELY CONTINUE UNTIL ABOUT 17Z TO 18Z. LOCATIONS FROM
KPHL TO THE SOUTH AND EAST HAVE THE BEST CHANCE TO STAY VFR THE
LONGEST TODAY. THE GENERAL EXPECTATION WILL BE FOR CEILINGS TO
LOWER TO IFR LATE-DAY TO EARLY EVENING AT ALL TAF SITES. HOWEVER,
CONFIDENCE IS ONLY MEDIUM AT THIS POINT THROUGH 23Z SATURDAY ON
CEILINGS, SINCE THE CEILINGS HAVE BEEN HIGHER THAN SUGGESTED FROM
SOME OUR FORECASTING TOOLS. VISIBILITIES WILL RANGE FROM MVFR TO
VFR ACROSS THE REGION, BUT SOME IFR VSBYS ARE POSSIBLE AT TIMES,
ESPECIALLY FOR KRDG AND KABE. A GENERAL EASTERLY WIND UNDER 10
KNOTS IS EXPECTED.
MUCH HIGHER CONFIDENCE TONIGHT FOR IFR CEILINGS WITH LOWERING
VISIBILITIES AND RAIN DEVELOPING BY 06Z SUNDAY FROM SOUTH TO
NORTH. IFR OR LOWER CEILINGS AND VISIBILITIES FROM 09Z INTO
SUNDAY MORNING WITH RAIN. WINDS WILL ALSO INCREASE AND BECOME MORE
SOUTHEASTERLY TOWARD SUNDAY MORNING AROUND 15 KNOTS WITH HIGHER
GUSTS TO 25 KNOTS. LLWS POSSIBLE FROM KPHL TO THE SOUTHEAST
TOWARD KACY AFTER 09Z SUNDAY. MODERATE CONFIDENCE IN LLWS.
OUTLOOK...
SUNDAY MORNING...EARLY IFR CONDITIONS IN SHOWERY-BRIEFLY HEAVY
RAINS. POSSIBLE ISOLATED TSTM. SE WINDS GUSTY 20-25 KT EXCEPT
POSSIBLY 40-45 KT IN A TSTM. LLWS VCNTY KMIV AND KACY.
SUNDAY AFTERNOON...BECOMING VFR CIGS AOA 3500 FT WITH A POSSIBLE
RESIDUAL BAND OF SHOWERS ACCOMPANY THE COLD FRONT. WINDS SHIFTING
SOUTHWEST THEN WEST AND GUSTY 25-35 KT.
SUNDAY NIGHT-MONDAY...MOSTLY VFR. GUSTY WEST-NORTHWEST WINDS
25-30 KT.
MONDAY NIGHT...VFR.
TUESDAY-WEDNESDAY...VFR. GUSTY SOUTH-SOUTHWEST WINDS BETWEEN 20
AND 25 KT TUESDAY, BECOMING WEST-NORTHWEST TUESDAY NIGHT INTO
WEDNESDAY. GUSTS INCREASING TO 30 TO 35 KT WEDNESDAY.
&&
.MARINE...
CURRENTLY, WAVE HEIGHTS ARE FIVE TO SEVEN FEET ON THE OCEAN
WATERS AND WILL CONTINUE TO BUILD SLOWLY INTO TONIGHT. WINDS WILL
REMAIN OUT OF THE EAST UNDER SCA CRITERIA TODAY BUT WILL RAMP UP
AFTER MIDNIGHT TONIGHT, REACHING 30 KNOTS TOWARD SUNRISE SUNDAY.
STRONGER WINDS A FEW THOUSAND FEET UP IN THE ATMOSPHERE MAY MIX
DOWN LEADING TO EVEN LOCALLY HIGHER WIND GUSTS TOWARD SUNRISE
SUNDAY.
ATLC COAST: SINCE ADVISORY SEAS ARE IN PROGRESS, WE CONTINUED THE
SCA HEADLINE INTO TONIGHT BUT THE SCA WILL PROBABLY BE DISCONTINUED
AT 330 PM FOR ONE PRIMARY HEADLINE AS GALE WARNING WINDS DRAW
CLOSER TO TIME ZERO.
DE BAY: SCA CANCELLED SINCE THE PREDOMINANT INTERMITTENT GALE ON
SUNDAY SUPERSEDES THE BRIEF TRANSITION FROM NON ADVISORY TO GALE
WARNING LATE TONIGHT.
OUTLOOK...
SEA SURFACE TEMPERATURES REMAIN VERY WARM FOR JANUARY...NEAR 50F
WHICH IS ABOUT 8 DEGREES ABOVE NORMAL. THIS CONTRIBUTES TO GREATER
INSTABILITY IN WESTERLY TO NORTHERLY FLOW COLD AIR PATTERNS AND
POSSIBLY STRONGER THAN MODELED WINDS. THIS COULD WELL AGAIN BE A
FACTOR IN STRONG COLD AIR ADVECTION WIND TRANSFER SUNDAY NIGHT.
SUNDAY-SUNDAY NIGHT...GALE WARNING ISSUED, FIRST FOR 1-3 HOURS SE
INFLOW GUSTS NEAR 35KT DURING THE MORNING. WE MAY NEED A SPECIAL
MARINE WARNING FOR ISOLATED TSTM GUSTS 40-45 KT. THEN A 9 TO 12
HOUR PERIOD OF WESTERLY GALES IS ANTICIPATED FOR LATE SUNDAY OR
MORE LIKELY SUNDAY NIGHT.
MONDAY-TUESDAY...OTHER THAN A BRIEF BREAK LATE MONDAY NIGHT INTO
EARLY TUESDAY, WINDS AND SEAS LIKELY TO REMAIN ABOVE SMALL CRAFT
CRITERIA THROUGH TUESDAY.
WEDNESDAY...THERE IS A HIGH PROBABILITY FOR GALE FORCE NORTHWEST
WIND GUSTS OF 35-40 KT.
&&
.TIDES/COASTAL FLOODING...
WITH THE NEW MOON TODAY AND AN INCREASING FLOW EASTERLY FLOW,
TIDES COULD APPROACH THE MINOR COASTAL FLOOD THRESHOLD, ESPECIALLY
SUNDAY. CURRENTLY THE TIDE WITH THE HIGHEST FORECAST IS SUNDAY
MORNING, BUT EVEN THIS MORNING IT WILL BE WITHIN AN INCH OR 2 OF
FLOOD ALONG THE ATLANTIC COAST.
FOR NOW ITS A MARGINAL CHANCE OF MINOR COASTAL FLOODING AND NO
ADVISORY IS BEING ISSUED ATTM.
ALSO, BEHIND THE STORM SYSTEM, STRONG NORTHWEST WINDS WILL DEVELOP.
CURRENT ETSS FORECASTS IN INDICATING THE POSSIBILITY OF APPROACHING
BLOW OUT FOR SOME AREAS, ESPECIALLY THE DELAWARE BAY AND POSSIBLY
THE TIDAL DELAWARE RIVER.
&&
.CLIMATE...
OUR 330 AM FORECAST HAS RECORD HIGHS FORECAST SUNDAY AT SEVERAL
LOCATIONS, INCLUDING KPHL, KTTN AND KRDG, WITH RECORD EQUALING OR
JUST A DEGREE SHY OF RECORD AT KACY, KILG, KABE, KGED.
DAILY RECORD HIGHS FOR SUNDAY JAN 10 ARE LISTED BELOW:
LOCATION RECORD YEAR
------------------------------
ATLANTIC CITY 63 1930
PHILADELPHIA 63 1950
WILMINGTON 64 1930
ALLENTOWN 60 1924
TRENTON 62 1950
GEORGETOWN 67 1950
READING 58 1939
MOUNT POCONO 57 1998
WE`LL BRING THE SNOW CLIMATOLOGY BACK EARLY NEXT WEEK ONCE WE GET
THROUGH THE SUNDAY WARM EVENT AND HAVE A BETTER FEEL FOR A COUPLE
OF SNOW THREATS NEXT WEEK.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 5 AM EST SUNDAY FOR ANZ450>455.
GALE WARNING FROM 5 AM SUNDAY TO 6 AM EST MONDAY FOR ANZ430-
431-450>455.
&&
$$
SYNOPSIS...DRAG
NEAR TERM...GAINES/KLINE
SHORT TERM...GAINES
LONG TERM...DRAG
AVIATION...DRAG/GAINES/KLINE
MARINE...DRAG/GAINES/KLINE
TIDES/COASTAL FLOODING...DRAG
CLIMATE...DRAG
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
649 AM EST SAT JAN 9 2016
.SYNOPSIS...
HIGH PRESSURE FROM EASTERN CANADA DOWN TO THE MID ATLANTIC STATES
WEAKENS LATE TODAY. LOW PRESSURE IN THE OHIO VALLEY THIS EVENING
INTENSIFIES RAPIDLY IS IT CROSSES PENNSYLVANIA AND NEW YORK STATE
SUNDAY. IT DRAWS A STRONG WARM FRONT NORTHWARD THROUGH OUR AREA
SUNDAY MORNING, THEN A STRONG COLD FRONT PASSES OFF THE COAST
SUNDAY AFTERNOON. HIGH PRESSURE BUILDS TO OUR SOUTH LATE MONDAY.
GREAT LAKES LOW PRESSURE TUESDAY SENDS A STRONG COLD FRONT ACROSS
THE MID ATLANTIC STATES TUESDAY EVENING. THAT LOW REFORMS ALONG
COASTAL NEW ENGLAND AND INTENSIFIES RAPIDLY ON WEDNESDAY. HIGH
PRESSURE BUILDS TO OUR SOUTH ON THURSDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
WINTER WEATHER ADVISORY REMAINS IN EFFECT FOR MONROE, PA AND
SUSSEX, NJ UNTIL 9 AM. TEMPERATURES ARE ABOVE FREEZING WITH THE
EXCEPTION OF SOME LOCATIONS IN MONROE AND SUSSEX COUNTIES. A FEW
SPOTTY SHOWERS OF FREEZING RAIN HAVE OCCURRED OVER THE PAST
COUPLE OF HOURS AND MAY CONTINUE TO DO SO FOR THE NEXT FEW HOURS.
OTHERWISE, TODAY LOOKS TO BE A CLOUDY DAY ACROSS THE REGION AS A
WARM FRONTAL BOUNDARY LIFTS NORTHWARD INTO NEW ENGLAND AND LOW
PRESSURE DEVELOPS OFF THE SOUTHEAST UNTIED STATES COASTLINE. THIS
WILL RESULT IN WARMER AND MOISTER BEING ADVECTED INTO THE REGION
WITH EASTERLY WINDS FROM 5-10 MPH. DAYTIME TEMPERATURES SHOULD RISE
TO AROUND 50 FOR MOST LOCATIONS WITH THE POCONOS STRUGGLING TO GET
OUT OF THE UPPER 30`S. BOTH THE HRRR AND RAP MESOSCALE MODELS ARE
TRYING TO SPIT OUT A BRIEF SHOWER OR TWO TODAY, SO HAVE LOW OR
SLIGHT CHANCE POPS ACROSS THE REGION TODAY. THE MAJORITY OF THE
REGION WILL STAY DRY THROUGH THE DAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SUNDAY/...
THE LOW PRESSURE IN THE SOUTHEAST UNITED STATES WILL CONTINUE TO
MOVE QUICKLY NORTHWARD TONIGHT REACHING OUR AREA BY SUNDAY MORNING
WITH A WARM FRONT EXTENDING EAST OF THE LOW PRESSURE CENTER. AN
AGGRESSIVE LLJ MODELED NEAR 60 KNOTS WILL CONTINUE TO SEND NORTHWARD
WARMER AND MOIST AIR INTO THE REGION. MOISTURE LIFTING OVER THE WARM
FRONT WILL LEAD TO WIDESPREAD RAIN BREAKING OUT TO OUR SOUTH LATE
SATURDAY. THE RAIN WILL INCREASE IN COVERAGE AND INTENSITY AS THE
NIGHT GOES ON WITH ALL LOCATIONS SEEING A STEADY RAIN BY SUNDAY
MORNING. TEMPERATURES WILL ACTUALLY RISE OVERNIGHT AND THE FORECAST
DOES GO WARMER WITH THE TEMPERATURES OVERNIGHT THAN WHAT THE MAV/MET
GUIDANCE SUGGESTS DUE TO THE LLJ INFLUENCE. AROUND HALF AN INCH OF
RAIN SHOULD FALL TONIGHT WITH ADDITIONAL RAIN ON SUNDAY. SOME OF THE
HEAVIER INTERVALS OF RAIN MAY CAUSE SOME PONDING OF WATER ON
ROADWAYS.
WINDS WILL INCREASE AS WELL, THE GFS, ECMWF AND NAM ALL
SUGGEST WINDS AT 925 MB REACH AT LEAST 50 MPH BY SUNDAY MORNING SE
OF PHILADELPHIA. WHILE THE STRONGEST WINDS WILL LIKELY BE ON SUNDAY,
THE FORECAST DOES GO STRONGER THAN GUIDANCE WITH THE WINDS AFTER
MIDNIGHT TONIGHT. SOME EAST TO SOUTHEAST WIND GUSTS AROUND 25 MPH
ARE POSSIBLE BY SUNDAY MORNING.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
500 MB: A NEGATIVE TILT SHORT WAVE RIPS NEWD THROUGH THE NORTHEAST
SUNDAY FOLLOWED BY THE DEVELOPMENT OF A FULL LATITUDE TROUGH ALONG
THE EAST COAST NEXT TUESDAY AND THEN WESTERLY FLOW DEVELOPS BY NEXT
THURSDAY BEFORE A NEW TROUGH FORMS IN THE CENTRAL USA NEXT WEEKEND.
TEMPERATURES: AFTER RECORD OR NEAR RECORD WARMTH SUNDAY AND MAXIMUM
TEMPERATURES NEARLY 25 DEGREES ABOVE NORMAL, CALENDAR DAY AVERAGES
WILL COOL TO NEAR NORMAL MONDAY AND TUESDAY, THEN SLIP A FEW DEGREES
BELOW NORMAL WEDNESDAY. THEREAFTER THERE IS SOME UNCERTAINTY...
BUT OVERALL NEAR OR SLIGHTLY BELOW NORMAL THURSDAY AND FRIDAY.
FORECAST BASIS: UNLESS OTHERWISE NOTED, A 50 50 BLEND 00Z/9 GFS/NAM
MOS GUIDANCE SUNDAY-SUNDAY NIGHT, THEREAFTER THE 00Z/9 GFS MEX MOS
MONDAY AND TUESDAY, THEN FOR TUESDAY NIGHT-FRIDAY GENERALLY THE
06Z/9 SUPERBLEND WHICH INCLUDES 00Z/9 GFS MEX GUIDANCE AND WPC
GUIDANCE.
THE DAILIES...
SUNDAY...A STORMY MORNING WITH AN OPPORTUNITY FOR A STRONG TSTM
IN STRONG SE INFLOW WITH INSTABILITY, ESPECIALLY ALOFT WHERE SWI
WILL BE BRIEFLY NEAR -2C, TT IN THE LOWER 50S AND RAPIDLY FALLING
SFC PRES. THIS COULD MEAN ISOLATED WIND GUSTS 40-50 MPH, ESPECIALLY
DELMARVA AND COASTAL NJ.
WE MAY EVENTUALLY NEED A WIND ADVY FOR THE NEAREST 5 MILES OF THE NJ
COAST IN THE 10Z-15Z TIME FRAME AND THIS IS WHERE I`VE GREATEST
CONFIDENCE ON VERIFYING NON CONVECTIVE 46 MPH SE WIND GUSTS.
BRIEF POOR DRAINAGE STREET FLOODING IN THE MORNING BUT OTRW NO
STREAM FLOODING EXPECTED.
TIDES WILL APPROACH MINOR ADVISORY STAGE IN THE 12Z-14Z TIME FRAME
BUT NO ADVISORY ATTM.
A WSHIFT TO WSW IN THE AFTERNOON WITH RECORD OR NEAR RECORD WARMTH
DURING MIDDAY BEGINNING TO BE SWEPT SEAWARD AND MAYBE ONE LAST
BAND OF SHOWERS PASSING EASTWARD AS A COLD FRONT MOVES THROUGH OUR
FORECAST AREA.
SUNDAY NIGHT...P/C, WINDY AND TURNING COLDER. GUSTY WEST WINDS 30-40
MPH. STRONG PRESSURE RISES DURING THE EVENING ACCOMPANIES THE INFLUX
OF COLDER DRIER AIR. SMALL CHC OF FLURRIES IN THE POCONOS.
MONDAY...DRY AND BREEZY. WESTERLY WIND GUSTS TO 25 MPH. .
TUESDAY...CHANCE OF SNOW SHOWERS OR FLURRIES IN THE DESTABILIZING
AIRMASS AS A STRONG TROUGH DEVELOPS ALONG THE EAST COAST. GUSTY
SOUTHWEST WINDS 20 TO 25 MPH SHIFTING TO WEST AT NIGHT WITH GUSTS
20 TO 30 MPH.
WEDNESDAY...WINDY AND COLD. DRY WITH EXCEPTION ALONG AND NORTH OF
I-78 WHERE THERE ARE MODEL INDICATIONS OF STEEP LAPSE RATES AND
POSSIBLE FLURRIES. WESTERLY WINDS WILL BE GUSTING 30 TO POSSIBLY
40 MPH.
THURSDAY...DIMINISHING WIND AND NOT QUITE AS COLD.
FRIDAY...UNCERTAINTY. FOR NOW, FORECASTING QUIET WEATHER (NOT THE
OUTLIER 00Z/9 ECMWF OPERATIONAL SOLUTION)
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
MOST LOCATIONS ARE CURRENTLY VARYING BETWEEN MVFR AND VFR
CEILINGS, WITH KRDG AND KABE MAINLY SEEING MVFR TO IFR CEILINGS.
THIS WILL LIKELY CONTINUE TILL ABOUT 16Z. LOCATIONS FROM KPHL TO
THE SOUTH AND EAST HAVE THE BEST CHANCE TO STAY VFR THE LONGEST
TODAY. THE GENERAL EXPECTATION WILL BE FOR CEILINGS TO LOWER TO
IFR THIS AFTERNOON AT ALL TAF SITES. HOWEVER, CONFIDENCE IS ONLY
MEDIUM AT THIS POINT THROUGH 23Z SATURDAY ON CEILINGS, SINCE THE
CEILINGS HAVE BEEN HIGHER THAN SUGGESTED FROM SOME OUR FORECASTING
TOOLS. VISIBILITIES WILL RANGE FROM MVFR TO VFR ACROSS THE REGION.
GENERAL EASTERLY WIND UNDER 10 KNOTS.
MUCH HIGHER CONFIDENCE TONIGHT FOR IFR CEILINGS WITH LOWERING
VISIBILITIES AND RAIN DEVELOPING BY 06Z SUNDAY FROM SOUTH TO
NORTH. IFR OR LOWER CEILINGS AND VISIBILITIES FROM 09Z INTO
SUNDAY MORNING WITH RAIN. WINDS WILL ALSO INCREASE AND BECOME MORE
SOUTHEASTERLY TOWARD SUNDAY MORNING AROUND 15 KNOTS WITH HIGHER
GUSTS TO 25 KNOTS. LLWS POSSIBLE FROM KPHL TO THE SOUTHEAST
TOWARD KACY AFTER 09Z SUNDAY. MODERATE CONFIDENCE IN LLWS.
OUTLOOK...
SUNDAY MORNING...EARLY IFR CONDITIONS IN SHOWERY-BRIEFLY HEAVY
RAINS. POSSIBLE ISOLATED TSTM. SE WINDS GUSTY 20-25 KT EXCEPT
POSSIBLY 40-45 KT IN A TSTM. LLWS VCNTY KMIV AND KACY.
SUNDAY AFTERNOON...BECOMING VFR CIGS AOA 3500 FT WITH A POSSIBLE
RESIDUAL BAND OF SHOWERS ACCOMPANY THE COLD FRONT. WINDS SHIFTING
SOUTHWEST THEN WEST AND GUSTY 25-35 KT.
SUNDAY NIGHT-MONDAY...MOSTLY VFR. GUSTY WEST-NORTHWEST WINDS
25-30 KT.
MONDAY NIGHT...VFR.
TUESDAY-WEDNESDAY...VFR. GUSTY SOUTH-SOUTHWEST WINDS BETWEEN 20
AND 25 KT TUESDAY, BECOMING WEST-NORTHWEST TUESDAY NIGHT INTO
WEDNESDAY. GUSTS INCREASING TO 30 TO 35 KT WEDNESDAY.
&&
.MARINE...
CURRENTLY WAVE HEIGHTS ARE SEVEN TO EIGHT FEET ON THE OCEAN WATERS
AND WILL CONTINUE TO BUILD SLOWLY INTO TONIGHT. WINDS WILL REMAIN
OUT OF THE EAST UNDER SCA CRITERIA TODAY BUT WILL RAMP UP AFTER
MIDNIGHT TONIGHT, REACHING 30 KNOTS TOWARD SUNRISE SUNDAY.
STRONGER WINDS A FEW THOUSAND FEET UP IN THE ATMOSPHERE MAY MIX
DOWN LEADING TO EVEN LOCALLY HIGHER WIND GUSTS TOWARD SUNRISE
SUNDAY.
ATLC COAST: SINCE ADVISORY SEAS ARE IN PROGRESS, WE CONTINUED THE
SCA HEADLINE INTO TONIGHT BUT THE SCA WILL PROBABLY BE DISCONTINUED
AT 330 PM FOR ONE PRIMARY HEADLINE AS GALE WARNING WINDS DRAW
CLOSER TO TIME ZERO.
DE BAY: SCA CANCELLED SINCE THE PREDOMINANT INTERMITTENT GALE ON
SUNDAY SUPERSEDES THE BRIEF TRANSITION FROM NON ADVISORY TO GALE
WARNING LATE TONIGHT.
OUTLOOK...
SEA SURFACE TEMPERATURES REMAIN VERY WARM FOR JANUARY...NEAR 50F
WHICH IS ABOUT 8 DEGREES ABOVE NORMAL. THIS CONTRIBUTES TO GREATER
INSTABILITY IN WESTERLY TO NORTHERLY FLOW COLD AIR PATTERNS AND
POSSIBLY STRONGER THAN MODELED WINDS. THIS COULD WELL AGAIN BE A
FACTOR IN STRONG COLD AIR ADVECTION WIND TRANSFER SUNDAY NIGHT.
SUNDAY-SUNDAY NIGHT...GALE WARNING ISSUED, FIRST FOR 1-3 HOURS SE
INFLOW GUSTS NEAR 35KT DURING THE MORNING. WE MAY NEED A SPECIAL
MARINE WARNING FOR ISOLATED TSTM GUSTS 40-45 KT. THEN A 9 TO 12
HOUR PERIOD OF WESTERLY GALES IS ANTICIPATED FOR LATE SUNDAY OR
MORE LIKELY SUNDAY NIGHT.
MONDAY-TUESDAY...OTHER THAN A BRIEF BREAK LATE MONDAY NIGHT INTO
EARLY TUESDAY, WINDS AND SEAS LIKELY TO REMAIN ABOVE SMALL CRAFT
CRITERIA THROUGH TUESDAY.
WEDNESDAY...THERE IS A HIGH PROBABILITY FOR GALE FORCE NORTHWEST
WIND GUSTS OF 35-40 KT.
&&
.TIDES/COASTAL FLOODING...
WITH THE NEW MOON TODAY AND AN INCREASING FLOW EASTERLY FLOW,
TIDES COULD APPROACH THE MINOR COASTAL FLOOD THRESHOLD, ESPECIALLY
SUNDAY. CURRENTLY THE TIDE WITH THE HIGHEST FORECAST IS SUNDAY
MORNING, BUT EVEN THIS MORNING IT WILL BE WITHIN AN INCH OR 2 OF
FLOOD ALONG THE ATLANTIC COAST.
FOR NOW ITS A MARGINAL CHANCE OF MINOR COASTAL FLOODING AND NO
ADVISORY IS BEING ISSUED ATTM.
ALSO, BEHIND THE STORM SYSTEM, STRONG NORTHWEST WINDS WILL DEVELOP.
CURRENT ETSS FORECASTS IN INDICATING THE POSSIBILITY OF APPROACHING
BLOW OUT FOR SOME AREAS, ESPECIALLY THE DELAWARE BAY AND POSSIBLY
THE TIDAL DELAWARE RIVER.
&&
.CLIMATE...
OUR 330 AM FORECAST HAS RECORD HIGHS FORECAST SUNDAY AT SEVERAL
LOCATIONS, INCLUDING KPHL, KTTN AND KRDG, WITH RECORD EQUALING OR
JUST A DEGREE SHY OF RECORD AT KACY, KILG, KABE, KGED.
DAILY RECORD HIGHS FOR SUNDAY JAN 10 ARE LISTED BELOW:
LOCATION RECORD YEAR
------------------------------
ATLANTIC CITY 63 1930
PHILADELPHIA 63 1950
WILMINGTON 64 1930
ALLENTOWN 60 1924
TRENTON 62 1950
GEORGETOWN 67 1950
READING 58 1939
MOUNT POCONO 57 1998
WE`LL BRING THE SNOW CLIMATOLOGY BACK EARLY NEXT WEEK ONCE WE GET
THROUGH THE SUNDAY WARM EVENT AND HAVE A BETTER FEEL FOR A COUPLE
OF SNOW THREATS NEXT WEEK.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...WINTER WEATHER ADVISORY UNTIL 9 AM EST THIS MORNING FOR PAZ055.
NJ...WINTER WEATHER ADVISORY UNTIL 9 AM EST THIS MORNING FOR NJZ001.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 5 AM EST SUNDAY FOR ANZ450>455.
GALE WARNING FROM 5 AM SUNDAY TO 6 AM EST MONDAY FOR ANZ430-
431-450>455.
&&
$$
SYNOPSIS...DRAG
NEAR TERM...GAINES
SHORT TERM...GAINES
LONG TERM...DRAG 649A
AVIATION...DRAG/GAINES 649A
MARINE...DRAG/GAINES 649A
TIDES/COASTAL FLOODING... 649A
CLIMATE...649A
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
624 AM EST SAT JAN 9 2016
.SYNOPSIS...
HIGH PRESSURE FROM EASTERN CANADA DOWN TO THE MID ATLANTIC STATES
WEAKENS LATE TODAY. LOW PRESSURE IN THE OHIO VALLEY THIS EVENING
INTENSIFIES RAPIDLY IS IT CROSSES PENNSYLVANIA AND NEW YORK STATE
SUNDAY. IT DRAWS A STRONG WARM FRONT NORTHWARD THROUGH OUR AREA
SUNDAY MORNING, THEN A STRONG COLD FRONT PASSES OFF THE COAST
SUNDAY AFTERNOON. HIGH PRESSURE BUILDS TO OUR SOUTH LATE MONDAY.
GREAT LAKES LOW PRESSURE TUESDAY SENDS A STRONG COLD FRONT ACROSS
THE MID ATLANTIC STATES TUESDAY EVENING. THAT LOW REFORMS ALONG
COASTAL NEW ENGLAND AND INTENSIFIES RAPIDLY ON WEDNESDAY. HIGH
PRESSURE BUILDS TO OUR SOUTH ON THURSDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
WINTER WEATHER ADVISORY REMAINS IN EFFECT FOR MONROE, PA AND
SUSSEX, NJ UNTIL 9 AM. TEMPERATURES ARE ABOVE FREEZING WITH THE
EXCEPTION OF SOME LOCATIONS IN MONROE AND SUSSEX COUNTIES. A FEW
SPOTTY SHOWERS OF FREEZING RAIN HAVE OCCURRED OVER THE PAST
COUPLE OF HOURS AND MAY CONTINUE TO DO SO FOR THE NEXT FEW HOURS.
OTHERWISE, TODAY LOOKS TO BE A CLOUDY DAY ACROSS THE REGION AS A
WARM FRONTAL BOUNDARY LIFTS NORTHWARD INTO NEW ENGLAND AND LOW
PRESSURE DEVELOPS OFF THE SOUTHEAST UNTIED STATES COASTLINE. THIS
WILL RESULT IN WARMER AND MOISTER BEING ADVECTED INTO THE REGION
WITH EASTERLY WINDS FROM 5-10 MPH. DAYTIME TEMPERATURES SHOULD RISE
TO AROUND 50 FOR MOST LOCATIONS WITH THE POCONOS STRUGGLING TO GET
OUT OF THE UPPER 30`S. BOTH THE HRRR AND RAP MESOSCALE MODELS ARE
TRYING TO SPIT OUT A BRIEF SHOWER OR TWO TODAY, SO HAVE LOW OR
SLIGHT CHANCE POPS ACROSS THE REGION TODAY. THE MAJORITY OF THE
REGION WILL STAY DRY THROUGH THE DAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SUNDAY/...
THE LOW PRESSURE IN THE SOUTHEAST UNITED STATES WILL CONTINUE TO
MOVE QUICKLY NORTHWARD TONIGHT REACHING OUR AREA BY SUNDAY MORNING
WITH A WARM FRONT EXTENDING EAST OF THE LOW PRESSURE CENTER. AN
AGGRESSIVE LLJ MODELED NEAR 60 KNOTS WILL CONTINUE TO SEND NORTHWARD
WARMER AND MOIST AIR INTO THE REGION. MOISTURE LIFTING OVER THE WARM
FRONT WILL LEAD TO WIDESPREAD RAIN BREAKING OUT TO OUR SOUTH LATE
SATURDAY. THE RAIN WILL INCREASE IN COVERAGE AND INTENSITY AS THE
NIGHT GOES ON WITH ALL LOCATIONS SEEING A STEADY RAIN BY SUNDAY
MORNING. TEMPERATURES WILL ACTUALLY RISE OVERNIGHT AND THE FORECAST
DOES GO WARMER WITH THE TEMPERATURES OVERNIGHT THAN WHAT THE MAV/MET
GUIDANCE SUGGESTS DUE TO THE LLJ INFLUENCE. AROUND HALF AN INCH OF
RAIN SHOULD FALL TONIGHT WITH ADDITIONAL RAIN ON SUNDAY. SOME OF THE
HEAVIER INTERVALS OF RAIN MAY CAUSE SOME PONDING OF WATER ON
ROADWAYS.
WINDS WILL INCREASE AS WELL, THE GFS, ECMWF AND NAM ALL
SUGGEST WINDS AT 925 MB REACH AT LEAST 50 MPH BY SUNDAY MORNING SE
OF PHILADELPHIA. WHILE THE STRONGEST WINDS WILL LIKELY BE ON SUNDAY,
THE FORECAST DOES GO STRONGER THAN GUIDANCE WITH THE WINDS AFTER
MIDNIGHT TONIGHT. SOME EAST TO SOUTHEAST WIND GUSTS AROUND 25 MPH
ARE POSSIBLE BY SUNDAY MORNING.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
500 MB: A NEGATIVE TILT SHORT WAVE RIPS NEWD THROUGH THE NORTHEAST
SUNDAY FOLLOWED BY THE DEVELOPMENT OF A FULL LATITUDE TROUGH ALONG
THE EAST COAST NEXT TUESDAY AND THEN WESTERLY FLOW NEXT THURSDAY
BEFORE A NEW TROUGH FORMS IN THE CENTRAL USA BY NEXT WEEKEND.
TEMPERATURES: AFTER RECORD OR NEAR RECORD WARMTH SUNDAY AND MAXIMUM
TEMPERATURES NEARLY 25 DEGREES ABOVE NORMAL, CALENDAR DAY AVERAGES
WILL COOL TO NEAR NORMAL MONDAY AND TUESDAY, THEN SLIP A FEW DEGREES
BELOW NORMAL WEDNESDAY. THEREAFTER THERE IS SOME UNCERTAINTY...
BUT OVERALL NEAR OR SLIGHTLY BELOW NORMAL THURSDAY AND FRIDAY.
FORECAST BASIS: UNLESS OTHERWISE NOTED, A 50 50 BLEND 00Z/9 GFS/NAM
MOS GUIDANCE SUNDAY-SUNDAY NIGHT, THEREAFTER THE 00Z/9 GFS MEX MOS
MONDAY AND TUESDAY, THEN FOR TUESDAY NIGHT-FRIDAY GENERALLY THE
06Z/9 SUPERBLEND WHICH INCLUDES 00Z/9 GFS MEX GUIDANCE AND WPC
GUIDANCE.
THE DAILIES...
SUNDAY...A STORMY MORNING WITH AN OPPORTUNITY FOR A STRONG TSTM
IN STRONG SE INFLOW WITH INSTABILITY, ESPECIALLY ALOFT WHERE SWI
WILL BE BRIEFLY NEAR -2C, TT IN THE LOWER 50S AND RAPIDLY FALLING
SFC PRES. THIS COULD MEAN ISOLATED WIND GUSTS 40-50 MPH, ESPECIALLY
DELMARVA AND COASTAL NJ.
WE MAY EVENTUALLY NEED A WIND ADVY FOR THE NEAREST 5 MILES OF THE NJ
COAST IN THE 10Z-15Z TIME FRAME AND THIS IS WHERE I`VE GREATEST
CONFIDENCE ON VERIFYING NON CONVECTIVE 46 MPH SE WIND GUSTS.
BRIEF POOR DRAINAGE STREET FLOODING IN THE MORNING BUT OTRW NO
STREAM FLOODING EXPECTED.
TIDES WILL APPROACH MINOR ADVISORY STAGE IN THE 12Z-14Z TIME FRAME
BUT NO ADVISORY ATTM.
A WSHIFT TO WSW IN THE AFTERNOON WITH RECORD OR NEAR RECORD
WARMTH DURING MIDDAY BEGINNING TO BE SWEPT SEAWARD AND MAYBE ONE
LAST BAND OF SHOWERS?.
SUNDAY NIGHT...P/C, WINDY AND TURNING COLDER. GUSTY WEST WINDS 30-40
MPH. STRONG PRESSURE RISES DURING THE EVENING ACCOMPANIES THE INFLUX
OF COLDER DRIER AIR. SMALL CHC OF FLURRIES IN THE POCONOS.
MONDAY...DRY.
TUESDAY...CHANCE OF SNOW SHOWERS OR FLURRIES IN THE DESTABILIZING
AIRMASS AS A STRONG TROUGH DEVELOPS ALONG THE EAST COAST. GUSTY
SOUTHWEST WINDS 20 TO 25 MPH SHIFTING TO WEST AT NIGHT WITH GUSTS
20 TO 30 MPH.
WEDNESDAY...WINDY AND COLD. DRY WITH EXCEPTION ALONG AND NORTH OF
I-78 WHERE MODEL INDICATIONS OF STEEP LAPSE RATES AND POSSIBLE
FLURRIES. WESTERLY WINDS WILL BE GUSTING 30 TO POSSIBLY 40 MPH.
THURSDAY...DIMINISHING WIND AND NOT QUITE AS COLD.
FRIDAY...UNCERTAINTY. FOR NOW, FORECASTING QUIET WEATHER (NOT THE
00Z/9 ECMWF OPERATIONAL SOLUTION)
&&
.AVIATION /11Z SATURDAY THROUGH WEDNESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
MOST LOCATIONS ARE CURRENTLY VARYING BETWEEN MVFR AND VFR
CEILINGS, WITH KRDG AND KABE MAINLY SEEING MVFR TO IFR CEILINGS.
THIS WILL LIKELY CONTINUE TILL ABOUT 16Z. LOCATIONS FROM KPHL TO
THE SOUTH AND EAST HAVE THE BEST CHANCE TO STAY VFR THE LONGEST
TODAY. THE GENERAL EXPECTATION WILL BE FOR CEILINGS TO LOWER TO
IFR THIS AFTERNOON AT ALL TAF SITES. HOWEVER, CONFIDENCE IS ONLY
MEDIUM AT THIS POINT THROUGH 23Z SATURDAY ON CEILINGS, SINCE THE
CEILINGS HAVE BEEN HIGHER THAN SUGGESTED FROM SOME OUR FORECASTING
TOOLS. VISIBILITIES WILL RANGE FROM MVFR TO VFR ACROSS THE REGION.
GENERAL EASTERLY WIND UNDER 10 KNOTS.
MUCH HIGHER CONFIDENCE TONIGHT FOR IFR CEILINGS WITH LOWERING
VISIBILITIES AND RAIN DEVELOPING BY 06Z SUNDAY FROM SOUTH TO
NORTH. IFR OR LOWER CEILINGS AND VISIBILITIES FROM 09Z INTO
SUNDAY MORNING WITH RAIN. WINDS WILL ALSO INCREASE AND BECOME MORE
SOUTHEASTERLY TOWARD SUNDAY MORNING AROUND 15 KNOTS WITH HIGHER
GUSTS TO 25 KNOTS. LLWS POSSIBILE FROM KPHL TO THE SOUTHEAST
TOWARD KACY AFTER 09Z SUNDAY. MODERATE CONFIDENCE IN LLWS.
OUTLOOK...
SUNDAY MORNING...EARLY IFR CONDITIONS IN SHOWERY BRIEFLY HEAVY
RAINS, POSSIBLE ISOLATED TSTM. SE WINDS GUSTY 20-25 KT EXCEPT
POSSIBLY 40-45 KT IN A TSTM. LLWS VCNTY KMIV AND KACY.
SUNDAY AFTERNOON...BECOMING VFR CIGS AOA 3500 FT WITH A POSSIBLE
RESIDUAL BAND OF SHOWERS ACCOMPANY THE COLD FRONT. WINDS SHIFTING
SOUTHWEST THEN WEST AND GUSTY 25-35 KT.
SUNDAY NIGHT-MONDAY...MOSTLY VFR. GUSTY WEST-NORTHWEST WINDS
25-30 KT.
MONDAY NIGHT...VFR.
TUESDAY-WEDNESDAY...VFR. GUSTY SOUTH-SOUTHWEST WINDS BETWEEN 20
AND 25 KT TUESDAY, BECOMING WEST-NORTHWEST TUESDAY NIGHT INTO
WEDNESDAY. GUSTS INCREASING TO 30 TO 35 KT WEDNESDAY.
&&
.MARINE...
CURRENTLY WAVE HEIGHTS ARE SIX TO SEVEN FEET ON THE OCEAN WATERS
AND WILL CONTINUE TO BUILD SLOWLY THROUGH THE DAY TODAY AND INTO
TONIGHT. WINDS WILL REMAIN OUT OF THE EAST UNDER SCA CRITERIA
TODAY BUT WILL RAMP UP AFTER MIDNIGHT TONIGHT, REACHING 30 KNOTS
TOWARD SUNRISE SUNDAY. STRONGER WINDS A FEW THOUSAND FEET UP IN
THE ATMOSPHERE MAY MIX DOWN LEADING TO EVEN LOCALLY HIGHER WIND
GUSTS TOWARD SUNRISE SUNDAY.
ATLC COAST: SINCE ADVISORY SEAS ARE IN PROGRESS, WE CONTINUED THE
SCA HEADLINE INTO TONIGHT BUT THE SCA WILL PROBABLY BE DISCONTINUED
AT 330 PM FOR ONE PRIMARY HEADLINE AS GALE WARNING WINDS DRAW
CLOSER TO TIME ZERO.
DE BAY: SCA CANCELLED SINCE THE PREDOMINANT INTERMITTENT GALE ON
SUNDAY SUPERSEDES THE BRIEF TRANSITION FROM NON ADVISORY TO GALE
WARNING EARLY SUNDAY.
OUTLOOK...
SEA SURFACE TEMPERATURES REMAIN VERY WARM FOR JANUARY...NEAR 50F
WHICH IS ABOUT 8 DEGREES ABOVE NORMAL. THIS CONTRIBUTES TO GREATER
INSTABILITY IN WESTERLY TO NORTHERLY FLOW COLD AIR PATTERNS AND
POSSIBLY STRONGER THAN MODELED WINDS. THIS COULD WELL AGAIN BE A
FACTOR IN STRONG COLD AIR ADVECTION WIND TRANSFER SUNDAY NIGHT.
SUNDAY-SUNDAY NIGHT...GALE WARNING ISSUED, FIRST FOR 1-3 HOURS SE
INFLOW GUSTS NEAR 35KT DURING THE MORNING. WE MAY NEED A SPECIAL
MARINE WARNING FOR ISOLATED TSTM GUSTS 40-45 KT. THEN A 9 TO 12
HOUR PERIOD OF WESTERLY GALES IS ANTICIPATED FOR LATE SUNDAY OR
MORE LIKELY SUNDAY NIGHT.
MONDAY-TUESDAY...OTHER THAN A BRIEF BREAK LATE MONDAY NIGHT INTO
EARLY TUESDAY, WINDS AND SEAS LIKELY TO REMAIN ABOVE SMALL CRAFT
CRITERIA THOUGH TUESDAY.
WEDNESDAY...THERE IS A HIGH PROBABILITY FOR GALE FORCE NORTHWEST
WIND GUSTS OF 35-40 KT.
&&
.TIDES/COASTAL FLOODING...
WITH THE NEW MOON ON SATURDAY AND AN INCREASING FLOW EASTERLY
FLOW, TIDES COULD APPROACH THE MINOR COASTAL FLOOD LEVEL SUNDAY.
CURRENTLY THE TIDE WITH THE HIGHEST FORECAST IS SUNDAY MORNING.
FOR NOW ITS A MARGINAL CHANCE OF MINOR COASTAL FLOODING AND NO
ADVISORY IS BEING ISSUED ATTM.
ALSO, BEHIND THE STORM SYSTEM, STRONG NORTHWEST WINDS WILL DEVELOP.
CURRENT ETSS FORECASTS IN INDICATING THE POSSIBILITY OF APPROACHING
BLOW OUT FOR SOME AREAS, ESPECIALLY THE DELAWARE BAY AND POSSIBLY
THE TIDAL DELAWARE RIVER.
&&
.CLIMATE...
RECORD HIGHS LIKELY SUNDAY AT SEVERAL LOCATIONS.
DAILY RECORD HIGHS FOR SUNDAY JAN 10 ARE LISTED BELOW:
LOCATION RECORD YEAR
------------------------------
ATLANTIC CITY 63 1930
PHILADELPHIA 63 1950
WILMINGTON 64 1930
ALLENTOWN 60 1924
TRENTON 62 1950
GEORGETOWN 67 1950
READING 58 1939
MOUNT POCONO 57 1998
WE`LL BRING THE SNOW CLIMATOLOGY BACK EARLY NEXT WEEK ONCE WE GET
THROUGH THE SUNDAY WARM EVENT AND HAVE A BETTER FEEL FOR A COUPLE
OF SNOW THREATS NEXT WEEK.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...WINTER WEATHER ADVISORY UNTIL 9 AM EST THIS MORNING FOR PAZ055.
NJ...WINTER WEATHER ADVISORY UNTIL 9 AM EST THIS MORNING FOR NJZ001.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 5 AM EST SUNDAY FOR ANZ450>455.
GALE WARNING FROM 5 AM SUNDAY TO 6 AM EST MONDAY FOR ANZ430-
431-450>455.
&&
$$
SYNOPSIS...DRAG
NEAR TERM...GAINES
SHORT TERM...GAINES
LONG TERM...DRAG
AVIATION...DRAG/GAINES
MARINE...DRAG/GAINES
TIDES/COASTAL FLOODING...
CLIMATE...
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
408 AM EST SAT JAN 9 2016
.SYNOPSIS...
HIGH PRESSURE FROM EASTERN CANADA DOWN TO THE MID ATLANTIC STATES
WEAKENS LATE TODAY. LOW PRESSURE IN THE OHIO VALLEY THIS EVENING
INTENSIFIES RAPIDLY IS IT CROSSES PENNSYLVANIA AND NEW YORK STATE
SUNDAY. IT DRAWS A STRONG WARM FRONT NORTHWARD THROUGH OUR AREA
SUNDAY MORNING, THEN A STRONG COLD FRONT PASSES OFF THE COAST
SUNDAY AFTERNOON. HIGH PRESSURE BUILDS TO OUR SOUTH LATE MONDAY.
GREAT LAKES LOW PRESSURE TUESDAY SENDS A STRONG COLD FRONT ACROSS
THE MID ATLANTIC STATES TUESDAY EVENING. THAT LOW REFORMS ALONG
COASTAL NEW ENGLAND AND INTENSIFIES RAPIDLY ON WEDNESDAY. HIGH
PRESSURE BUILDS TO OUR SOUTH ON THURSDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
CANCELED THE WINTER WEATHER ADVISORY FOR ALL BUT MONROE, PA AND
SUSSEX, NJ WITH THIS FORECAST PACKAGE. SHORT RANGE MESOSCALE
MODELS CONTINUE TO SHOW LITTLE TO NO QPF EXPECTED IN THE NEXT FEW
HOURS. ALSO TEMPERATURES ARE ABOVE FREEZING ALMOST EVERYWHERE IN
THE PREVIOUS ADVISORY WITH THE EXCEPTION OF MONROE AND SUSSEX
COUNTIES. THIS IS WHERE SOME PATCHES OF THE COUNTY THE TEMPERATURE
IS NEAR FREEZING AND SOME VERY LIGHT FREEZING RAIN MAY OCCUR IF
QPF OCCURS IN THE NEXT FEW HOURS.
OTHERWISE, TODAY LOOKS TO BE A CLOUDY DAY ACROSS THE REGION AS A
WARM FRONTAL BOUNDARY LIFTS NORTHWARD INTO NEW ENGLAND AND LOW
PRESSURE DEVELOPS OFF THE SOUTHEAST UNTIED STATES COASTLINE. THIS
WILL RESULT IN WARMER AND MOISTER BEING ADVECTED INTO THE REGION
WITH EASTERLY WINDS FROM 5-10 MPH. DAYTIME TEMPERATURES SHOULD RISE
TO AROUND 50 FOR MOST LOCATIONS WITH THE POCONOS STRUGGLING TO GET
OUT OF THE UPPER 30`S. BOTH THE HRRR AND RAP MESOSCALE MODELS ARE
TRYING TO SPIT OUT A BRIEF SHOWER OR TWO TODAY, SO HAVE LOW OR
SLIGHT CHANCE POPS ACROSS THE REGION TODAY. THE MAJORITY OF THE
REGION WILL STAY DRY THROUGH THE DAY
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SUNDAY/...
THE LOW PRESSURE IN THE SOUTHEAST UNITED STATES WILL CONTINUE TO
MOVE QUICKLY NORTHWARD TONIGHT REACHING OUR AREA BY SUNDAY MORNING
WITH A WARM FRONT EXTENDING EAST OF THE LOW PRESSURE CENTER. AN
AGGRESSIVE LLJ MODELED NEAR 60 KNOTS WILL CONTINUE TO SEND NORTHWARD
WARMER AND MOIST AIR INTO THE REGION. MOISTURE LIFTING OVER THE WARM
FRONT WILL LEAD TO WIDESPREAD RAIN BREAKING OUT TO OUR SOUTH LATE
SATURDAY. THE RAIN WILL INCREASE IN COVERAGE AND INTENSITY AS THE
NIGHT GOES ON WITH ALL LOCATIONS SEEING A STEADY RAIN BY SUNDAY
MORNING. TEMPERATURES WILL ACTUALLY RISE OVERNIGHT AND THE FORECAST
DOES GO WARMER WITH THE TEMPERATURES OVERNIGHT THAN WHAT THE MAV/MET
GUIDANCE SUGGESTS DUE TO THE LLJ INFLUENCE. AROUND HALF AN INCH OF
RAIN SHOULD FALL TONIGHT WITH ADDITIONAL RAIN ON SUNDAY. SOME OF THE
HEAVIER INTERVALS OF RAIN MAY CAUSE SOME PONDING OF WATER ON
ROADWAYS.
WINDS WILL INCREASE AS WELL, THE GFS, ECMWF AND NAM ALL
SUGGEST WINDS AT 925 MB REACH AT LEAST 50 MPH BY SUNDAY MORNING SE
OF PHILADELPHIA. WHILE THE STRONGEST WINDS WILL LIKELY BE ON SUNDAY,
THE FORECAST DOES GO STRONGER THAN GUIDANCE WITH THE WINDS AFTER
MIDNIGHT TONIGHT. SOME EAST TO SOUTHEAST WIND GUSTS AROUND 25 MPH
ARE POSSIBLE BY SUNDAY MORNING.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
500 MB: A NEGATIVE TILT SHORT WAVE RIPS NEWD THROUGH THE NORTHEAST
SUNDAY FOLLOWED BY THE DEVELOPMENT OF A FULL LATITUDE TROUGH ALONG
THE EAST COAST NEXT TUESDAY AND THEN WESTERLY FLOW NEXT THURSDAY
BEFORE A NEW TROUGH FORMS IN THE CENTRAL USA BY NEXT WEEKEND.
TEMPERATURES: AFTER RECORD OR NEAR RECORD WARMTH SUNDAY AND MAXIMUM
TEMPERATURES NEARLY 25 DEGREES ABOVE NORMAL, CALENDAR DAY AVERAGES
WILL COOL TO NEAR NORMAL MONDAY AND TUESDAY, THEN SLIP A FEW DEGREES
BELOW NORMAL WEDNESDAY. THEREAFTER THERE IS SOME UNCERTAINTY...
BUT OVERALL NEAR OR SLIGHTLY BELOW NORMAL THURSDAY AND FRIDAY.
FORECAST BASIS: UNLESS OTHERWISE NOTED, A 50 50 BLEND 00Z/9 GFS/NAM
MOS GUIDANCE SUNDAY-SUNDAY NIGHT, THEREAFTER THE 00Z/9 GFS MEX MOS
MONDAY AND TUESDAY, THEN FOR TUESDAY NIGHT-FRIDAY GENERALLY THE
06Z/9 SUPERBLEND WHICH INCLUDES 00Z/9 GFS MEX GUIDANCE AND WPC
GUIDANCE.
THE DAILIES...
SUNDAY...A STORMY MORNING WITH AN OPPORTUNITY FOR A STRONG TSTM
IN STRONG SE INFLOW WITH INSTABILITY, ESPECIALLY ALOFT WHERE SWI
WILL BE BRIEFLY NEAR -2C, TT IN THE LOWER 50S AND RAPIDLY FALLING
SFC PRES. THIS COULD MEAN ISOLATED WIND GUSTS 40-50 MPH, ESPECIALLY
DELMARVA AND COASTAL NJ.
WE MAY EVENTUALLY NEED A WIND ADVY FOR THE NEAREST 5 MILES OF THE NJ
COAST IN THE 10Z-15Z TIME FRAME AND THIS IS WHERE I`VE GREATEST
CONFIDENCE ON VERIFYING NON CONVECTIVE 46 MPH SE WIND GUSTS.
BRIEF POOR DRAINAGE STREET FLOODING IN THE MORNING BUT OTRW NO
STREAM FLOODING EXPECTED.
TIDES WILL APPROACH MINOR ADVISORY STAGE IN THE 12Z-14Z TIME FRAME
BUT NO ADVISORY ATTM.
A WSHIFT TO WSW IN THE AFTERNOON WITH RECORD OR NEAR RECORD
WARMTH DURING MIDDAY BEGINNING TO BE SWEPT SEAWARD AND MAYBE ONE
LAST BAND OF SHOWERS?.
SUNDAY NIGHT...P/C, WINDY AND TURNING COLDER. GUSTY WEST WINDS 30-40
MPH. STRONG PRESSURE RISES DURING THE EVENING ACCOMPANIES THE INFLUX
OF COLDER DRIER AIR. SMALL CHC OF FLURRIES IN THE POCONOS.
MONDAY...DRY.
TUESDAY...CHANCE OF SNOW SHOWERS OR FLURRIES IN THE DESTABILIZING
AIRMASS AS A STRONG TROUGH DEVELOPS ALONG THE EAST COAST. GUSTY
SOUTHWEST WINDS 20 TO 25 MPH SHIFTING TO WEST AT NIGHT WITH GUSTS
20 TO 30 MPH.
WEDNESDAY...WINDY AND COLD. DRY WITH EXCEPTION ALONG AND NORTH OF
I-78 WHERE MODEL INDICATIONS OF STEEP LAPSE RATES AND POSSIBLE
FLURRIES. WESTERLY WINDS WILL BE GUSTING 30 TO POSSIBLY 40 MPH.
THURSDAY...DIMINISHING WIND AND NOT QUITE AS COLD.
FRIDAY...UNCERTAINTY. FOR NOW, FORECASTING QUIET WEATHER (NOT THE
00Z/9 ECMWF OPERATIONAL SOLUTION)
&&
.AVIATION /09Z SATURDAY THROUGH WEDNESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
MOST LOCATIONS ARE CURRENTLY VARYING BETWEEN MVFR AND VFR CEILINGS.
THIS WILL LIKELY CONTINUE TILL ABOUT 11Z. LOCATIONS FROM KPHL TO
THE SOUTH AND EAST HAVE THE BEST CHANCE TO STAY VFR THE LONGEST. THE
GENERAL EXPECTATION WILL BE FOR CEILINGS TO LOWER TO IFR AROUND 12Z
THIS MORNING. IFR CEILINGS ARE THEN EXPECTED TO BE PREDOMINANT
THROUGH SATURDAY. HOWEVER, CONFIDENCE IS LOW AT THIS POINT THROUGH
23Z SATURDAY ON CEILINGS, SINCE THE CEILINGS HAVE BEEN HIGHER THAN
SUGGESTED FROM SOME OUR FORECASTING TOOLS. VISIBILITIES WILL RANGE
FROM MVFR TO VFR ACROSS THE REGION.
MUCH HIGHER CONFIDENCE TONIGHT FOR IFR CEILINGS WITH LOWERING
VISIBILITIES AND RAIN DEVELOPING BY 06Z SUNDAY FROM SOUTH TO
NORTH.
OUTLOOK...
SUNDAY MORNING...EARLY IFR CONDITIONS IN SHOWERY BRIEFLY HEAVY
RAINS, POSSIBLE ISOLATED TSTM. SE WINDS GUSTY 20-25 KT EXCEPT
POSSIBLY 40-45 KT IN A TSTM. LLWS VCNTY KMIV AND KACY.
SUNDAY AFTERNOON...BECOMING VFR CIGS AOA 3500 FT WITH A POSSIBLE
RESIDUAL BAND OF SHOWERS ACCOMPANY THE COLD FRONT. WINDS SHIFTING
SOUTHWEST THEN WEST AND GUSTY 25-35 KT.
SUNDAY NIGHT-MONDAY...MOSTLY VFR. GUSTY WEST-NORTHWEST WINDS
25-30 KT.
MONDAY NIGHT...VFR.
TUESDAY-WEDNESDAY...VFR. GUSTY SOUTH-SOUTHWEST WINDS BETWEEN 20
AND 25 KT TUESDAY, BECOMING WEST-NORTHWEST TUESDAY NIGHT INTO
WEDNESDAY. GUSTS INCREASING TO 30 TO 35 KT WEDNESDAY.
&&
.MARINE...
CURRENTLY WAVE HEIGHTS ARE SIX TO SEVEN FEET ON THE OCEAN WATERS
AND WILL CONTINUE TO BUILD SLOWLY THROUGH THE DAY TODAY AND INTO
TONIGHT. WINDS WILL REMAIN OUT OF THE EAST UNDER SCA CRITERIA
TODAY BUT WILL RAMP UP AFTER MIDNIGHT TONIGHT, REACHING 30 KNOTS
TOWARD SUNRISE SUNDAY. STRONGER WINDS A FEW THOUSAND FEET UP IN
THE ATMOSPHERE MAY MIX DOWN LEADING TO EVEN LOCALLY HIGHER WIND
GUSTS TOWARD SUNRISE SUNDAY.
ATLC COAST: SINCE ADVISORY SEAS ARE IN PROGRESS, WE CONTINUED THE
SCA HEADLINE INTO TONIGHT BUT THE SCA WILL PROBABLY BE DISCONTINUED
AT 330 PM FOR ONE PRIMARY HEADLINE AS GALE WARNING WINDS DRAW
CLOSER TO TIME ZERO.
DE BAY: SCA CANCELLED SINCE THE PREDOMINANT INTERMITTENT GALE ON
SUNDAY SUPERSEDES THE BRIEF TRANSITION FROM NON ADVISORY TO GALE
WARNING EARLY SUNDAY.
OUTLOOK...
SEA SURFACE TEMPERATURES REMAIN VERY WARM FOR JANUARY...NEAR 50F
WHICH IS ABOUT 8 DEGREES ABOVE NORMAL. THIS CONTRIBUTES TO GREATER
INSTABILITY IN WESTERLY TO NORTHERLY FLOW COLD AIR PATTERNS AND
POSSIBLY STRONGER THAN MODELED WINDS. THIS COULD WELL AGAIN BE A
FACTOR IN STRONG COLD AIR ADVECTION WIND TRANSFER SUNDAY NIGHT.
SUNDAY-SUNDAY NIGHT...GALE WARNING ISSUED, FIRST FOR 1-3 HOURS SE
INFLOW GUSTS NEAR 35KT DURING THE MORNING. WE MAY NEED A SPECIAL
MARINE WARNING FOR ISOLATED TSTM GUSTS 40-45 KT. THEN A 9 TO 12
HOUR PERIOD OF WESTERLY GALES IS ANTICIPATED FOR LATE SUNDAY OR
MORE LIKELY SUNDAY NIGHT.
MONDAY-TUESDAY...OTHER THAN A BRIEF BREAK LATE MONDAY NIGHT INTO
EARLY TUESDAY, WINDS AND SEAS LIKELY TO REMAIN ABOVE SMALL CRAFT
CRITERIA THOUGH TUESDAY.
WEDNESDAY...THERE IS A HIGH PROBABILITY FOR GALE FORCE NORTHWEST
WIND GUSTS OF 35-40 KT.
&&
.TIDES/COASTAL FLOODING...
WITH THE NEW MOON ON SATURDAY AND AN INCREASING FLOW EASTERLY
FLOW, TIDES COULD APPROACH THE MINOR COASTAL FLOOD LEVEL SUNDAY.
CURRENTLY THE TIDE WITH THE HIGHEST FORECAST IS SUNDAY MORNING.
FOR NOW ITS A MARGINAL CHANCE OF MINOR COASTAL FLOODING AND NO
ADVISORY IS BEING ISSUED ATTM.
ALSO, BEHIND THE STORM SYSTEM, STRONG NORTHWEST WINDS WILL DEVELOP.
CURRENT ETSS FORECASTS IN INDICATING THE POSSIBILITY OF APPROACHING
BLOW OUT FOR SOME AREAS, ESPECIALLY THE DELAWARE BAY AND POSSIBLY
THE TIDAL DELAWARE RIVER.
&&
.CLIMATE...
RECORD HIGHS LIKELY SUNDAY AT SEVERAL LOCATIONS.
DAILY RECORD HIGHS FOR SUNDAY JAN 10 ARE LISTED BELOW:
LOCATION RECORD YEAR
------------------------------
ATLANTIC CITY 63 1930
PHILADELPHIA 63 1950
WILMINGTON 64 1930
ALLENTOWN 60 1924
TRENTON 62 1950
GEORGETOWN 67 1950
READING 58 1939
MOUNT POCONO 57 1998
WE`LL BRING THE SNOW CLIMATOLOGY BACK EARLY NEXT WEEK ONCE WE GET
THROUGH THE SUNDAY WARM EVENT AND HAVE A BETTER FEEL FOR A COUPLE
OF SNOW THREATS NEXT WEEK.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...WINTER WEATHER ADVISORY UNTIL 9 AM EST THIS MORNING FOR PAZ055.
NJ...WINTER WEATHER ADVISORY UNTIL 9 AM EST THIS MORNING FOR NJZ001.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 5 AM EST SUNDAY FOR ANZ450>455.
GALE WARNING FROM 5 AM SUNDAY TO 6 AM EST MONDAY FOR ANZ430-
431-450>455.
&&
$$
SYNOPSIS...DRAG 408
NEAR TERM...GAINES 408
SHORT TERM...GAINES 408
LONG TERM...DRAG 408
AVIATION...DRAG/GAINES 408
MARINE...DRAG/GAINES 408
TIDES/COASTAL FLOODING...408
CLIMATE...408
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
1239 AM EST SAT JAN 9 2016
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN IN PLACE ACROSS EASTERN CANADA AND NOSE
ITS WAY DOWN THE EASTERN SEABOARD THROUGH SATURDAY. A WARM FRONT
WILL LIFT NORTHWEST OF THE AREA TONIGHT INTO EARLY SATURDAY MORNING
AS A WEAK AREA OF LOW PRESSURE LIFTS THROUGH THE GREAT LAKES. A
STRONGER LOW PRESSURE SYSTEM WILL LIFT THROUGH THE OHIO RIVER VALLEY
INTO THE NORTHEAST SATURDAY NIGHT INTO SUNDAY, LIFTING AN OCCLUDED
FRONTAL SYSTEM ACROSS THE AREA SUNDAY. HIGH PRESSURE WILL BUILD TO
THE SOUTH MONDAY INTO MONDAY NIGHT, BEFORE AN AREA OF LOW PRESSURE
MOVES TO OUR NORTH TUESDAY INTO WEDNESDAY. THIS LOW WILL PULL A COLD
FRONT ACROSS THE AREA TUESDAY NIGHT. HIGH PRESSURE BUILDS TO OUR
SOUTH WEDNESDAY THROUGH THURSDAY, WHILE ANOTHER AREA OF LOW PRESSURE
MOVES THROUGH THE GREAT LAKES INTO NEW ENGLAND THURSDAY.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
A WARM FRONTAL BOUNDARY IS MOVING THROUGH THE REGION WITH
INCREASED MOISTURE AND SOME LIFT. THE LIFT IS SUFFICIENT ENOUGH
TO GENERATE SOME SPOTTY LIGHT PRECIPITATION. SOME CONCERN EXISTS
IN THE ADVISORY AREA ACROSS NORTHERN NEW JERSEY AND THE POCONOS
ON IF ANY MIXED PRECIPITATION WILL OCCUR. THE NAM AND GFS SHOW
THE POTENTIAL FOR A 1/100TH OR TWO OF QPF BUT THE HRRR AND RAP
ARE DRY AFTER 4AM. WILL CONTINUE WITH THE ADVISORY ATTM.
TEMPERATURES WILL FALL A COUPLE OF MORE DEGREES WITH THE
POSSIBILITY OF WET- BULBING LEADING TO ANOTHER DEGREE OR TWO OF
COOLING IN THE POCONOS. ANY MINOR ICE ACCUMULATION MAY LEAD TO
SLICK SPOTS OVERNIGHT.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM SUNDAY/...
THE LIGHT PRECIPITATION SHOULD LIFT TO OUR NORTHEAST ON SATURDAY.
THE SURFACE RIDGE AXIS IS EXPECTED TO CONTINUE PULLING OUT OF OUR
REGION EVEN AS SOME MID LEVEL RIDGING DEVELOPS ALOFT.
THERE IS FORECAST TO BE A FAIR AMOUNT OF LOW LEVEL MOISTURE
LINGERING IN OUR REGION ON SATURDAY AND IT WILL LIKELY REMAIN
TRAPPED UNDER A TEMPERATURE INVERSION. AS A RESULT, WE ARE
ANTICIPATING LOW CLOUDS FOR MOST OF THE DAY.
A LIGHT NORTHEAST TO EAST WIND IS EXPECTED AND MAXIMUM TEMPERATURES
SHOULD RANGE FROM AROUND 40 IN THE POCONOS TO THE MIDDLE 50S IN
SOUTHERN DELAWARE.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
AFTER A WARM AND WET START TO THE FORECAST THIS WEEKEND, THEN
COOLER AIR RETURNS TO THE AREA FOR THE REMAINDER OF THE WEEK.
AN OCCLUDED LOW PRESSURE SYSTEM WILL BE LIFTING OUT OF THE OHIO
VALLEY AND INTO THE EASTERN GREAT LAKES SATURDAY NIGHT INTO
SUNDAY, PULLING THE ASSOCIATED FRONTAL BOUNDARIES ACROSS THE AREA
EARLY SUNDAY MORNING. RAIN SHOULD BEGIN OVERRUNNING THE SYSTEM AND
START MOVING INTO OUR SOUTHERN AREAS DURING THE NIGHT SATURDAY,
THEN PROGRESS NORTHWARD THROUGH THE NIGHT AND INTO SUNDAY MORNING.
PW VALUES REACH AROUND AN INCH OR MORE, AND THERE COULD ALSO BE
SOME VERY WEAK INSTABILITY. SO THERE WILL BE THE POTENTIAL FOR
PERIODS OF MODERATE TO HEAVY RAINFALL OVERNIGHT INTO EARLY SUNDAY
MORNING. WHILE THERE COULD BE A FEW LIGHTNING STRIKES OR RUMBLES
OF THUNDER, WE HAVE KEPT THUNDER OUT OF THE GRIDS FOR NOW.
RAINFALL AMOUNTS WILL LIKELY REACH AT LEAST 0.5 TO 1.0 INCHES
ACROSS MUCH OF THE AREA, AND COULD REACH 1.5 INCHES ACROSS THE
NORTHERN AREAS. WE EXPECT THIS SHOULD FALL OVER A LONG ENOUGH
PERIOD THAT WE ARE NOT EXPECTING SIGNIFICANT FLOODING AT THIS
TIME, ALTHOUGH THERE COULD END UP BEING SOME FLOOD ADVISORIES
ISSUED FOR URBAN AND POOR DRAINAGE TYPE FLOODING.
RAIN SHOULD BE TAPERING OFF THROUGH THE DAY SUNDAY AS THE LOW
PRESSURE SYSTEM AND FRONTAL BOUNDARY LIFT TO OUR NORTH. AS THE
LOW PULLS TO THE NORTH SUNDAY NIGHT INTO MONDAY, HIGH PRESSURE
BEGINS TO BUILD TO THE SOUTH. THIS WILL CREATE A TIGHT PRESSURE
GRADIENT ACROSS THE AREA AND LEAD TO GUSTY WINDS SUNDAY INTO
MONDAY. DRY WEATHER WILL CONTINUE SUNDAY NIGHT INTO MONDAY NIGHT.
THE EXCEPTION WOULD BE POSSIBLY SOME LAKE EFFECT SNOW SHOWERS
ACROSS THE NORTH EARLY SUNDAY NIGHT.
ON TUESDAY, AN AREA OF LOW PRESSURE WILL MOVE OUT OF THE GREAT
LAKES REGION INTO SOUTHEASTERN CANADA, BRINGING A FRONTAL BOUNDARY
ACROSS THE AREA LATE TUESDAY INTO TUESDAY NIGHT. THE GFS IS
BEGINNING TO SHOW BETTER POTENTIAL FOR MORE MOISTURE AND LIFT
ASSOCIATED WITH THE PASSAGE OF THE SHORT WAVE ALOFT. THE ECMWF HAS
LESS MOISTURE, BUT DOES HAVE THE ENHANCED LIFT WITH THE SHORT
WAVE. SO WE`VE EXPANDED THE SLIGHT CHANCE OF SNOW SHOWERS FROM THE
NORTHERN TIER DURING THE DAY TUESDAY, TO COVER EVERYONE TUESDAY
NIGHT. WINDS COULD GUST 20-30 MPH AT TIMES DURING THE DAY TUESDAY
AS STRONGER WINDS MIX DOWN FROM ALOFT.
THIS SYSTEM WILL MOVE QUICKLY NORTHEAST WHILE HIGH PRESSURE
BUILDS TO OUR SOUTH WEDNESDAY INTO THURSDAY. ANOTHER QUICK MOVING
LOW PRESSURE SYSTEM WILL SLIDE TO OUR NORTH THURSDAY. THE SHORT
WAVE WITH THIS SYSTEM LOOKS MORE SUBDUED THAN THE ONE WEDNESDAY,
SO WE`VE KEPT THE FORECAST DRY EXCEPT ACROSS THE POCONOS WHERE
SOME LAKE EFFECT SHOWERS COULD POSSIBLY MAKE IT DOWN INTO THE
AREA.
WINDS COULD GUST 20-30 MPH AT TIMES WEDNESDAY THROUGH THURSDAY
AS STRONGER WINDS MIX DOWN FROM ALOFT. WEDNESDAY HAS THE
POTENTIAL FOR THE STRONGEST WIND GUSTS, MAYBE 35 MPH OR HIGHER AT
TIMES.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
CEILINGS ARE FORECAST TO FAVOR THE 2000 TO 3000 FOOT RANGE AT OUR
EIGHT TAF SITES INTO THE OVERNIGHT HOURS. HOWEVER, PATCHES OF
CLOUDS WITH BASES AROUND 1500 FEET MAY DRIFT OVERHEAD FROM THE
NORTHEAST AT TIMES. ALSO, SOME BRIEF BREAKS IN THE CLOUD COVER
WILL OCCUR ESPECIALLY FOR KMIV AND KACY.
PREVAILING CEILINGS ARE EXPECTED TO LOWER INTO THE 1000 TO 2000 FOOT
RANGE BY SUNRISE. AN AREA OF LIGHT RAIN IS ANTICIPATED TO MOVE
ACROSS THE NORTHWESTERN PART OF OUR REGION AND IT IS FORECAST TO
AFFECT KRDG AND KABE...THOUGH THERE IS AT LEAST A SMALL CHANCE AT
ALL OF THE TAF SITES.
LOW LEVEL MOISTURE SHOULD REMAIN TRAPPED IN OUR REGION FOR
SATURDAY. GUIDANCE HAS BE STEADILY BECOMING MORE OPTIMISTIC WITH
THE HEIGHT OF LOW CLOUDS, SO INCREASED THE PREVAILING CLOUD BASES
THROUGH THIS TIME TO BE IN THE UPPER END OF IFR OR LOWER END OF
MVFR. KACY AND KMIV HAVE THE BEST CHANCE OF SEEING PREDOMINANTLY
MVFR CONDITIONS.
THE WIND IS FORECAST TO REMAIN FROM THE NORTHEAST THROUGH THE TAF
PERIOD AT SPEEDS OF 10 KNOTS OR LESS.
OUTLOOK...
SATURDAY NIGHT-SUNDAY...IFR CONDITIONS WITH RAIN, POSSIBLY
MODERATE TO HEAVY AT TIMES. IMPROVING LATE SUNDAY.
SUNDAY NIGHT-MONDAY...MOSTLY VFR. GUSTY WEST-NORTHWEST WINDS
DEVELOPING. GUSTS 25-30 KT POSSIBLE.
MONDAY NIGHT...VFR.
TUESDAY-WEDNESDAY...VFR. GUSTY SOUTH-SOUTHWEST WINDS
POSSIBLE TUESDAY, BECOMING WEST-NORTHWEST TUESDAY NIGHT INTO
WEDNESDAY AND REMAINING GUSTY. GUSTS AROUND 20-30 KT TUESDAY-
TUESDAY NIGHT, WITH STRONGER WINDS POSSIBLE WEDNESDAY.
&&
.MARINE...
A NORTHEAST WIND OF 5 TO 15 KNOTS IS EXPECTED ON THE COASTAL
WATERS OF NEW JERSEY AND DELAWARE FOR TONIGHT AND SATURDAY WITH A
RIDGE OF HIGH PRESSURE NOSING DOWN INTO THE NORTHEASTERN STATES
AND A STRONG STORM SYSTEM WELL OUT OVER THE WESTERN NORTH
ATLANTIC. THE STORM SHOULD KEEP WAVE HEIGHTS ON OUR OCEAN WATERS
IN THE 4 TO 6 FOOT RANGE, SO THE SMALL CRAFT ADVISORY WILL REMAIN
IN EFFECT.
OUTLOOK...
SATURDAY NIGHT...SMALL CRAFT ADVISORY EXTENDED INTO SATURDAY
NIGHT AS SEAS EXPECTED TO BUILD BACK ABOVE 5 FEET. WINDS INCREASE
25-30 KT OVERNIGHT AHEAD OF APPROACHING STORM SYSTEM.
SUNDAY-SUNDAY NIGHT...GALE WATCH IN EFFECT AS WINDS EXPECTED TO
INCREASE TO AT LEAST 35 KT AHEAD OF AND BEHIND STORM SYSTEM.
MONDAY-TUESDAY...OTHER THAN A BRIEF BREAK LATE MONDAY NIGHT INTO
TUESDAY, WINDS AND SEAS LIKELY TO REMAIN ABOVE SMALL CRAFT
CRITERIA THOUGH TUESDAY.
WEDNESDAY...THERE IS A CHANCE GALE FORCE WINDS OF 35-40 KT
WEDNESDAY.
&&
.TIDES/COASTAL FLOODING...
WITH THE NEW MOON ON SATURDAY AND AN INCREASING FLOW EASTERLY
FLOW, TIDES COULD APPROACH THE MINOR COASTAL FLOOD LEVEL.
CURRENTLY THE TIDE WITH THE HIGHEST FORECAST IS SUNDAY MORNING.
ALSO, BEHIND THE STORM SYSTEM, STRONG NORTHWEST WINDS WILL
DEVELOP. CURRENT ETSS FORECASTS IN INDICATING THE POSSIBILITY OF
APPROACHING BLOW OUT FOR SOME AREAS, ESPECIALLY THE DELAWARE BAY
AND POSSIBLY THE TIDAL DELAWARE RIVER.
&&
.CLIMATE...
WE REMAIN WITHIN A COUPLE OF DEGREES OF THE DAILY RECORD HIGHS
FOR SUNDAY JAN 10 MAY BE CHALLENGED AT MOST OF OUR CLIMATE SITES.
THEY ARE LISTED BELOW:
LOCATION RECORD YEAR
------------------------------
ATLANTIC CITY 63 1930
PHILADELPHIA 63 1950
WILMINGTON 64 1930
ALLENTOWN 60 1924
TRENTON 62 1950
GEORGETOWN 67 1950
READING 58 1939
MOUNT POCONO 57 1998
WE`LL BRING THE SNOW CLIMATOLOGY BACK EARLY NEXT WEEK ONCE WE GET
THROUGH THE SUNDAY WARM EVENT AND HAVE A BETTER FEEL FOR A COUPLE
OF SNOW THREATS NEXT WEEK.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...WINTER WEATHER ADVISORY UNTIL 9 AM EST THIS MORNING FOR PAZ055.
WINTER WEATHER ADVISORY UNTIL 7 AM EST THIS MORNING FOR PAZ054-
062.
NJ...WINTER WEATHER ADVISORY UNTIL 9 AM EST THIS MORNING FOR NJZ001.
WINTER WEATHER ADVISORY UNTIL 7 AM EST THIS MORNING FOR NJZ007-
008.
DE...NONE.
MD...NONE.
MARINE...GALE WATCH FROM SUNDAY MORNING THROUGH LATE SUNDAY NIGHT FOR
ANZ430-431-450>455.
SMALL CRAFT ADVISORY UNTIL 6 AM EST SUNDAY FOR ANZ450>455.
SMALL CRAFT ADVISORY FROM 1 AM TO 6 AM EST SUNDAY FOR ANZ430-
431.
&&
$$
SYNOPSIS...MEOLA
NEAR TERM...GAINES/IOVINO/JOHNSON
SHORT TERM...IOVINO
LONG TERM...ROBERTSON
AVIATION...IOVINO/JOHNSON/ROBERTSON
MARINE...IOVINO/ROBERTSON
TIDES/COASTAL FLOODING...
CLIMATE...
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
100 PM EST SAT JAN 9 2016
.Aviation...
[Through 18Z Sunday] IFR ceilings and MVFR visibility will be the
most likely conditions that accompany a band of showers as it
traverses the forecast area from west to east this afternoon and
evening. Thunderstorms should be limited to areas along and south
of I-10 and perhaps the VLD area. Once the showers pass, a brief
return to LIFR ceilings is possible until later tonight when
conditions will improve to MVFR with a wind shift to the
northwest. These northwest winds will be gusty on Sunday.
&&
.Prev Discussion [920 AM EST]...
.Near Term [Through Today]...
Water vapor imagery shows and upper low over Oklahoma this morning.
Surface analysis shows weakening low pressure over Arkansas with
another low developing closer to the Gulf of Mexico (GOMEX) near
coastal Louisiana. A warm front is developing southeastward from
this low over the eastern GOMEX southwest of our marine area.
Regional radars show a cluster of thunderstorms tracking eastward
south of the MS/AL coastline. This is a remnant of a more organized
squall line that tracked across the Mississippi River overnight. The
12Z KTAE sounding sampled the 145-kt jet stream that extends across
the northern GOMEX. The sounding also shows the stable air mass is
place across the Big Bend.
Little has changed in our overall assessment of today`s severe
weather potential. We will find ourselves in a high-shear, low-CAPE
environment that is typical when frontal systems traverse the Gulf
Coast during winter. Deep layer shear values will be in the
impressive 70-85 knot range, but remain largely displaced northward
from the deep moisture and instability over the GOMEX. There is a
narrow zone where we could see sufficient overlap of shear and
instability to allow severe storms to develop. That includes our
coastal counties and marine area. The locally developed DVD severe
weather parameter from the 13Z RAP indicates this will mainly occur
in the afternoon and evening hours once the surface low tracks more
toward the northeast allowing the warm front to edge closer to the
coast. ECAM probabilities for severe gusts and strong updraft
helicity has been scaled back from what we were seeing yesterday to
include the same geographic threat area and SPC`s marginal risk
areas generally depicts this as well. The threat will be for
isolated damaging wind gusts and perhaps a tornado.
.Short Term [Tonight Through Monday]...
The shortwave currently over central Texas is forecast to be over
the Mississippi and Tennessee valleys by this evening and embedded
within the large, broad full CONUS trough. At the surface, low
pressure centered over the Ohio and Tennessee valleys is forecast
to move through the Midwest tonight and the Northeast on Sunday.
Much, if not all of the day`s convection will likely be through
the region by this evening. Should convection linger into the
evening a bit it will primarily be focused across the southeast
Big Bend of Florida, with a weakening rain shield over south-
central Georgia. The potential for an isolated severe storm will
still exist across primarily Taylor, Lafayette, and Dixie counties
early this evening. The primary threat with any supercells that
develop will be tornadoes and damaging winds.
After tonight, surface ridging will build into the Southeast
behind a cold front. Temperatures will fall to below seasonal
averages Sunday through Monday, with highs ranging from the upper
40s across southeast Alabama tomorrow, to the mid 60s across the
southeast Big Bend of Florida. Low to mid 50s will be common
area-wide on Monday. CAA from Sunday will linger into Sunday
night, forcing lows into the upper 20s across southeast Alabama
and southwest Georgia, up to the upper 30s across the southeast
Big Bend. Wind chill readings will essentially make it feel like
30 degrees and below, with some spots nearing the 20 degree wind
chill mark in the coldest spots.
.Long Term [Monday Night Through Saturday]...
The below normal temperatures will continue through Thursday as
another cold front (with no rain), moves through the region on
Tuesday. Monday night will be the closest to a radiational cooling
event, with little to no wind. CAA and wind chills are expected
again on Tuesday and Wednesday nights. Highs will remain solidly
in the 50s through Thursday, with overnight lows in the 30s. Wind
chills on Tues/Wed nights will likely only fall into the middle
20s across southeast Alabama and southwest Georgia.
Thursday through Saturday, models are essentially split and
cannot agree on placement or strength of a developing Gulf low.
Though, moderating temperatures and a chance for rain will likely
return by the end of the period.
.Marine...
Cautionary level winds are expected through Sunday night, ahead
of, and in the wake of a passing cold front. Another uptick in
winds will be possible behind a cold front early next week, though
at this time appear to remain below headline levels. Finally, late
next week there is the potential for another enhancement in winds
and seas associated with a developing Gulf low.
.Fire Weather...
With a moist air mass in place, there are no fire weather
concerns for this weekend. On Monday, a very dry air mass will
invade the region. Red Flag conditions are a possibility on
Monday.
.Hydrology...
The low pressure system today will, on average, bring less than a
quarter of an inch of rain across southeast Alabama and south
Georgia. Across north Florida, a half inch will be more common.
Isolated rainfall totals between 1 to 2 inches will be possible
should a strong thunderstorm reach land areas south of interstate
10. In general, this event is not expected to have a significant
impact on river levels or trends. The lower Choctawhatchee and
Apalachicola rivers remain at moderate flood levels this morning.
Though levels are steadily lowering across these rivers, they`ll
likely remain in flood for several more days. The lower Flint
River will drop below flood stage this evening.
&&
.Preliminary Point Temps/PoPs...
Tallahassee 54 56 34 55 31 / 20 0 0 0 0
Panama City 54 55 36 52 38 / 10 0 0 0 0
Dothan 47 49 29 52 30 / 30 0 0 0 0
Albany 50 52 29 52 30 / 40 0 0 0 0
Valdosta 55 57 33 55 31 / 60 0 0 0 0
Cross City 59 64 39 59 33 / 60 0 0 0 0
Apalachicola 57 58 39 54 38 / 10 0 0 0 0
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
FL...High Rip Current Risk through late tonight FOR Coastal Bay-
Coastal Franklin-Coastal Gulf-South Walton.
GA...NONE.
AL...NONE.
GM...NONE.
&&
$$
NEAR TERM...WOOL
SHORT TERM...HARRIGAN
LONG TERM...HARRIGAN
AVIATION...WOOL
MARINE...HARRIGAN
FIRE WEATHER...MCDERMOTT
HYDROLOGY...HARRIGAN
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
1005 AM EST SAT JAN 9 2016
.DISCUSSION...
...WARMER THIS AFTERNOON...
...SLIGHT CHANCE OF THUNDERSTORMS THIS EVENING...
.UPDATE...AREA OF STRATUS AND FOG AFFECTING EAST CENTRAL FL THIS
MORNING SHOULD BREAK UP AND DISSIPATE INTO MID DAY AS LOW LVL FLOW
TURNS SOUTHERLY AHEAD OF THE NEXT APPROACHING FRONT LATER TONIGHT.
SHORT RANGE MODELS INCLUDING THE HRRR BRING GULF CONVECTION TWD LAKE
COUNTY BETWEEN 5 AND 7 PM AND THEN EASTWARD ACROSS E CENTRAL FL THIS
EVENING. WILL MAKE ONLY MINOR ADJUSTMENTS TO FCST WITH HIGHS STILL
EXPECTED TO REACH THE UPPER 70S TO LOWER 80S ONCE MORNING STRATUS
DECK BREAKS UP. COULD BE A FEW STRONGER STORMS WITH LOCALLY HEAVY
RAIN AND GUSTY WINDS PUSHING INTO THE INTERIOR FROM THE WESTERN
PENINSULA THIS EVENING WITH MID LAYER FLOW AT 500 MBS TO 45-55
KNOTS AND H5 TEMPS COOLING A DEG OR TWO TO -11 TO -12 DEGS C THIS
EVENING.
&&
.AVIATION... LOW STRATUS AND FOG SHOULD BREAK UP AND LIFT BY 17Z AND
BECOMING VFR MOST AREAS BY 18Z. HRRR INDICATES GULF CONVECTION MAY
APPROACH KLEE 22Z-24Z AND AFFECT REMAINDER OF INTERIOR TERMINALS AND
POSSIBLY CSTL TERMINALS LATER INTO THE EVENING.
&&
.MARINE... UPDATE...NW WINDS THIS MORNING WILL BECOME S/SW THIS AFTN
AHEAD OF THE NEXT FRONTAL SYSTEM APPROACHING THE AREA TONIGHT.
SWELLS AT BUOY 41009 RUNNING SLIGHTLY HIGHER THAN GUID THIS MORNING
TO 7-8 FT. WILL CONTINUE EXERCISE CAUTION HEADLINES ALL MARINE AREAS
INTO THE AFTERNOON WITH SEAS TO 7 FT OFFSHORE. PREVIOUS DISCUSSION...
TODAY/TONIGHT...LOW PRESSURE IS FORECAST TO LIFT NE FROM THE LOWER MS
VALLEY AND STRENGTHEN AS IT REACHES THE EASTERN GREAT LAKES TONIGHT.
A WEAK INVERTED TROUGH ANALYZED JUST OFFSHORE THE FL EAST COAST WILL
PRODUCE A LIGHT NORTH FLOW ALONG THE COAST THIS MORNING. BUT WINDS
WILL SHIFT OUT OF THE S TO SW LATER THIS MORNING AND AFTERNOON AS AN
APPROACHING SYSTEM RAPIDLY MOVES EAST FROM THE GULF OF MEXICO. WIND
SPEEDS WILL BE AROUND 10 KNOTS THIS AFTERNOON BUT INCREASE 15-20
KNOTS OFFSHORE TONIGHT AHEAD OF A COLD FRONT. RAIN CHANCES LOOK
QUITE LOW OVER THE ATLC WATERS DURING THE DAY BUT FAST MOVING
SHOWERS WILL APPROACH FROM THE WEST BY EARLY EVENING INTO THE
OVERNIGHT.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 78 62 73 43 / 20 40 10 0
MCO 80 64 77 45 / 30 40 10 0
MLB 80 66 79 46 / 20 40 20 0
VRB 81 66 80 49 / 20 40 30 10
LEE 79 63 73 44 / 40 40 10 0
SFB 80 63 74 44 / 30 40 10 0
ORL 81 65 75 48 / 30 40 10 0
FPR 81 66 80 49 / 20 40 30 10
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
VOLKMER/SPRATT
AREA FORECAST DISCUSSION
NWS MIAMI FL
942 AM EST SAT JAN 9 2016
.UPDATE...
EARLY MORNING FOG CONTINUES TO BURN OFF, ALTHOUGH SOME AREAS OF
LOW VISIBILITY REMAIN, ESPECIALLY ALONG ALLIGATOR ALLEY AND U.S.
27. THE FOG SHOULD BE GONE BY 11 AM, IF NOT SOONER AS DEPTH OF THE
FOG LAYER IS QUITE SHALLOW.
PSEUDO-WARM FRONT OVER THE KEYS AND STRAITS OF FLORIDA, AS
DEPICTED ON VISIBLE SATELLITE IMAGERY AS A THIN BAND OF CLOUDS,
WILL MOVE NORTH TODAY AND LEAD TO SW WINDS AND SLOWLY INCREASING
MOISTURE ACROSS SOUTH FLORIDA. A WEAK SEA BREEZE COULD TRY TO PUSH
ONSHORE THE EAST COAST THIS AFTERNOON. INSTABILITY REMAINS
LIMITED TODAY ALTHOUGH WITH MODERATELY STRONG WIND FIELDS/DEEP-
LAYERED SHEAR OVERHEAD, IT WOULDN`T TAKE A LOT OF INSTABILITY TO
TRIGGER A FEW TSTMS TODAY. FOR NOW WILL KEEP FORECAST AS
IS...WHICH IS FOR ISOLATED SHOWERS AREA-WIDE.
SOME DISAGREEMENT AMONG MODEL SUITE REGARDING PRECIP TONIGHT IN
ADVANCE OF THE COLD FRONT. HRRR AND SOME OF THE WRF GUIDANCE
BRINGS PRECIP ONSHORE GULF COAST LATE THIS AFTERNOON, WHILE THE
RUC AND GLOBAL MODELS HOLD OFF UNTIL THIS EVENING/TONIGHT. CURRENT
FORECAST HAS GOOD TREND OF INCREASING RAIN CHANCES BETWEEN 00Z-
12Z. COULD SEE A FEW TSTMS TONIGHT AND MAY HAVE TO INTRODUCE
THUNDER TO FORECAST IN LATER UPDATES. /MOLLEDA
&&
.PREV DISCUSSION... /ISSUED 700 AM EST SAT JAN 9 2016/
AVIATION...
MAIN CONCERN THROUGH MID-MORNING IS LOW VISIBILITY/IFR CONDITIONS
IN FOG ACROSS MUCH OF SOUTH FLORIDA. SEVERAL SITES REPORTING SFC
VISIBILITY BELOW 1SM IN FOG AT 12Z THIS MORNING, BUT FOG IS
PATCHY AND SHALLOW AND AREAS NEAR/ALONG THE EAST COAST HAVE
ALREADY BROKEN OUT OF THE FOG. THEREFORE, EXPECT SIGNIFICANT
IMPROVEMENT BY 13Z, WITH MOST IF NOT ALL AREAS VFR BY 14Z. SFC WINDS
PREVAILING SW AHEAD OF A COLD FRONT IN THE GULF OF MEXICO WHICH
WILL BE AFFECTING THE AREA ON SUNDAY. MODELS SUGGEST A WEAK
SEA BREEZE COULD FORM ALONG THE IMMEDIATE EAST COAST, BUT WIND
SPEEDS ARE EXPECTED TO BE 10 KT OR LESS. MOISTURE INCREASES FROM
THE GULF OF MEXICO LATE TODAY AND TONIGHT, WITH SHOWERS MOVING
ONSHORE GULF COAST/KAPF THIS AFTERNOON AND TONIGHT. /MOLLEDA
PREV DISCUSSION... /ISSUED 420 AM EST SAT JAN 9 2016/
.ACTIVE WEATHER PATTERN FOR SOUTH FL INTO NEXT WEEK...
DISCUSSION...
A CHANGEABLE, ACTIVE WEATHER PATTERN WILL CONTINUE ACROSS SOUTH
FLORIDA INTO NEXT WEEK, POTENTIALLY REVVING UP DURING THE LATTER
PART OF NEXT WEEK...IN EL NINO STYLE.
THE MAIN IMPACT IN THE NEAR TERM IS DENSE FOG. THIS FOG HAS
BECOME FAIRLY WIDESPREAD OVER THE INTERIOR AND GULF COAST WITH
VISIBILITIES REPORTED LESS THAN A QUARTER OF MILE NEAR THE LAKE
AND NAPLES CONSISTENTLY NOW RECORDING M1/4SM. FOR THIS REASON, A
DENSE FOG ADVISORY WAS ISSUED FOR THE INTERIOR AND GULF COAST. FOG
IS PATCHY ACROSS THE EAST COAST METRO AND MAINLY IN THE 1-3SM
RANGE. WILL MONITOR VISIBILITY TRENDS TO SEE IF THE ADVISORY MAY
NEED AN EXPANSION EAST EARLY THIS MORNING.
AFTER THE FOG DISSIPATED BY MID MORNING...SKIES WILL BE PARTLY
SUNNY WITH DRY WEATHER PREVAILING. HOWEVER, THE NEXT IN A SERIES
OF SHORTWAVES WILL APPROACH FROM THE EASTERN GULF...BUT THIS WILL
BE LATE IN THE DAY, SO ALTHOUGH THERE IS THE POTENTIAL OF A FEW
SHOWERS DEVELOPING ACROSS SOUTH FL...IT APPEARS THE FOCUS WILL
REMAIN OFF TO THE WEST AND NORTH. GIVEN THIS AND ONLY MARGINAL
INSTABILITY, HAVE KEPT TSTORM MENTION OUT OF THE FORECAST FOR
TODAY.
LOW PRESSURE DEVELOPING OVER THE MID SOUTH WILL MOVE QUICKLY UP
THE TENNESSEE VALLEY REGION AND INTO THE EASTERN GREAT LAKES
THROUGH SUNDAY. ITS ASSOCIATED COLD FRONT WILL MOVE ACROSS
NORTHERN AND CENTRAL FL ON SUNDAY...SWEEPING ACROSS SOUTH FL
SUNDAY EVENING. MOISTURE AHEAD OF THIS FRONT LOOKS SUFFICIENT FOR
SCATTERED SHOWERS TONIGHT-SUNDAY. INSTABILITY LOOKS JUST TOO
MARGINAL WHILE THE MAIN ENERGY REMAINS DISPLACED OFF NORTH OF THE
AREA TO SUPPORT AN APPRECIABLE TSTORM RISK, SO FOR NOW HAVE KEPT
TSTORM MENTION OUT IN ADVANCE OF THIS FRONT.
MUCH COOLER AND DRIER AIR WILL ADVECT DOWN THE PENINSULA ON
NORTHERLY WINDS SUN NIGHT-MON. SO WHILE THIS WEEKEND WILL BE WARM
AND MODERATELY HUMID, A NOTICEABLE CHANGE WILL OCCUR BY MONDAY. IN
FACT...HIGHS ON MONDAY ARE FORECAST TO REMAIN IN THE 60S ACROSS
THE LAKE OKEECHOBEE REGION AND ONLY AROUND 70 ELSEWHERE.
THE AFOREMENTIONED FRONT DOESN`T GET TOO FAR SOUTH THOUGH...AND
YET ANOTHER SHORTWAVE IS FORECAST TO MOVE ACROSS THE GULF AND
ACROSS SOUTH FL ON TUE. THIS WILL RESULT IN AN OVERRUNING
SITUATION WITH SHOWERS TO BREAK OUT AS WARMER AIR ALOFT GLIDES
OVER THE RELATIVELY COOLER SURFACE AIRMASS THAT WILL BE IN PLACE.
HOW WET IT GETS ON TUESDAY IS IN QUESTION. STAYED CLOSE TO THE
MODEL BLENDS IN THE 50-60% RANGE, BUT WOULD NOT DOUBT POPS GO
HIGHER SOUTHERN LOCALES WITH TIME.
THAT SHORTWAVE DEPARTS TUE NIGHT WITH A DRY DAY FORECAST FOR
WEDNESDAY AHEAD OF THE NEXT POTENTIALLY MORE VIGOROUS SHORTWAVE.
GFS AND ECMWF SHOW THIS ENERGY ENTERING THE GULF OF MEXICO ON
THURSDAY THEN MOVING ACROSS FLORIDA THURSDAY NIGHT. BOTH
OPERATIONAL RUNS ARE BULLISH WITH SURFACE LOW PRESSURE
DEVELOPMENT...BUT MANY ENSEMBLE MEMBERS ARE LESS AGGRESSIVE...NO
SURPRISE THIS FAR OUT. HOWEVER, GIVEN THAT BOTH OPERATIONAL RUNS
OF GFS/ECMWF SHOW QUICK MOISTURE RECOVERY LATE THU ALONG WITH
IMPRESSIVE WIND FIELDS...IT IS A TIMEFRAME IN THE EXTENDED THAT
WE WILL BE MONITORING FOR POTENTIAL SEVERE THUNDERSTORMS. THERE IS
LOW CONFIDENCE NOW (AFTER ALL THIS ENERGY IS ALL THE WAY OUT IN
THE PACIFIC AT AROUND 158W!), BUT GIVEN THAT THIS EL NINO IS TIED
NOW FOR THE STRONGEST ON RECORD, AND WE KNOW THAT EL NINO`S FAVOR
AN UPTICK IN SEVERE WEATHER/TORNADOES ACROSS FLORIDA, WE WILL BE
MONITORING THIS CLOSELY IN THE DAYS AHEAD. /GREGORIA
MARINE...
NO HEADLINES NEEDED. A LONG PERIOD NE SWELL WILL CONTINUE TO
SLOWLY SUBSIDE ACROSS THE ATLANTIC WATERS. WINDS WILL PICK UP
WHILE TURNING NORTHERLY BEHIND A COLD FRONT SUN NIGHT-MON...BUT
RIGHT NOW SEAS ARE FORECAST TO REMAIN BELOW 7 FT. /GREGORIA
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 83 69 82 58 / 20 20 40 20
FORT LAUDERDALE 83 69 83 60 / 20 20 40 20
MIAMI 83 71 83 62 / 20 20 40 20
NAPLES 79 69 79 58 / 20 40 50 10
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...HIGH RIP CURRENT RISK UNTIL 7 PM EST THIS EVENING FOR FLZ168-172-
173.
AM...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
920 AM EST SAT JAN 9 2016
.Near Term [Through Today]...
Water vapor imagery shows and upper low over Oklahoma this morning.
Surface analysis shows weakening low pressure over Arkansas with
another low developing closer to the Gulf of Mexico (GOMEX) near
coastal Louisiana. A warm front is developing southeastward from
this low over the eastern GOMEX southwest of our marine area.
Regional radars show a cluster of thunderstorms tracking eastward
south of the MS/AL coastline. This is a remnant of a more organized
squall line that tracked across the Mississippi River overnight. The
12Z KTAE sounding sampled the 145-kt jet stream that extends across
the northern GOMEX. The sounding also shows the stable air mass is
place across the Big Bend.
Little has changed in our overall assessment of today`s severe
weather potential. We will find ourselves in a high-shear, low-CAPE
environment that is typical when frontal systems traverse the Gulf
Coast during winter. Deep layer shear values will be in the
impressive 70-85 knot range, but remain largely displaced northward
from the deep moisture and instability over the GOMEX. There is a
narrow zone where we could see sufficient overlap of shear and
instability to allow severe storms to develop. That includes our
coastal counties and marine area. The locally developed DVD severe
weather parameter from the 13Z RAP indicates this will mainly occur
in the afternoon and evening hours once the surface low tracks more
toward the northeast allowing the warm front to edge closer to the
coast. ECAM probabilities for severe gusts and strong updraft
helicity has been scaled back from what we were seeing yesterday to
include the same geographic threat area and SPC`s marginal risk
areas generally depicts this as well. The threat will be for
isolated damaging wind gusts and perhaps a tornado.
&&
.Hydrology...
The low pressure system today will, on average, bring less than a
quarter of an inch of rain across southeast Alabama and south
Georgia. Across north Florida, a half inch will be more common.
Isolated rainfall totals between 1 to 2 inches will be possible
should a strong thunderstorm reach land areas south of interstate
10. In general, this event is not expected to have a significant
impact on river levels or trends. The lower Choctawhatchee and
Apalachicola rivers remain at moderate flood levels this morning.
Though levels are steadily lowering across these rivers, they`ll
likely remain in flood for several more days. The lower Flint
River will drop below flood stage this evening.
&&
.Prev Discussion [626 AM EST]...
.Short Term [Tonight Through Monday]...
The shortwave currently over central Texas is forecast to be over
the Mississippi and Tennessee valleys by this evening and embedded
within the large, broad full CONUS trough. At the surface, low
pressure centered over the Ohio and Tennessee valleys is forecast
to move through the Midwest tonight and the Northeast on Sunday.
Much, if not all of the day`s convection will likely be through
the region by this evening. Should convection linger into the
evening a bit it will primarily be focused across the southeast
Big Bend of Florida, with a weakening rain shield over south-
central Georgia. The potential for an isolated severe storm will
still exist across primarily Taylor, Lafayette, and Dixie counties
early this evening. The primary threat with any supercells that
develop will be tornadoes and damaging winds.
After tonight, surface ridging will build into the Southeast
behind a cold front. Temperatures will fall to below seasonal
averages Sunday through Monday, with highs ranging from the upper
40s across southeast Alabama tomorrow, to the mid 60s across the
southeast Big Bend of Florida. Low to mid 50s will be common
area-wide on Monday. CAA from Sunday will linger into Sunday
night, forcing lows into the upper 20s across southeast Alabama
and southwest Georgia, up to the upper 30s across the southeast
Big Bend. Wind chill readings will essentially make it feel like
30 degrees and below, with some spots nearing the 20 degree wind
chill mark in the coldest spots.
.Long Term [Monday Night Through Saturday]...
The below normal temperatures will continue through Thursday as
another cold front (with no rain), moves through the region on
Tuesday. Monday night will be the closest to a radiational cooling
event, with little to no wind. CAA and wind chills are expected
again on Tuesday and Wednesday nights. Highs will remain solidly
in the 50s through Thursday, with overnight lows in the 30s. Wind
chills on Tues/Wed nights will likely only fall into the middle
20s across southeast Alabama and southwest Georgia.
Thursday through Saturday, models are essentially split and
cannot agree on placement or strength of a developing Gulf low.
Though, moderating temperatures and a chance for rain will likely
return by the end of the period.
.Aviation...
[Through 12Z Sunday] Expect patchy fog this morning. Current
visibilities are IFR and better. Most CIGs throughout the region
are currently LIFR and are forecast to become IFR after daybreak.
Showers and thunderstorms will move in to the region from the west
by late morning/early afternoon. A few storms may be severe,
particularly in the Florida counties. If these storms are able to
organize, the primary threat will be damaging winds and brief
tornadoes. MVFR conditions are likely beginning in the late
morning/early afternoon hours.
.Marine...
Cautionary level winds are expected through Sunday night, ahead
of, and in the wake of a passing cold front. Another uptick in
winds will be possible behind a cold front early next week, though
at this time appear to remain below headline levels. Finally, late
next week there is the potential for another enhancement in winds
and seas associated with a developing Gulf low.
.Fire Weather...
With a moist air mass in place, there are no fire weather
concerns for this weekend. On Monday, a very dry air mass will
invade the region. Red Flag conditions are a possibility on
Monday.
&&
.Preliminary Point Temps/PoPs...
Tallahassee 70 54 56 34 55 / 80 20 0 0 0
Panama City 69 54 55 36 52 / 80 10 0 0 0
Dothan 65 47 49 29 52 / 80 30 0 0 0
Albany 66 50 52 29 52 / 80 40 0 0 0
Valdosta 70 55 57 33 55 / 60 60 0 0 0
Cross City 75 59 64 39 59 / 50 60 0 0 0
Apalachicola 70 57 58 39 54 / 80 10 0 0 0
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
FL...High Rip Current Risk through late tonight FOR Coastal Bay-
Coastal Franklin-Coastal Gulf-South Walton.
GA...NONE.
AL...NONE.
GM...NONE.
&&
$$
NEAR TERM...WOOL
SHORT TERM...HARRIGAN
LONG TERM...HARRIGAN
AVIATION...MCDERMOTT
MARINE...HARRIGAN
FIRE WEATHER...MCDERMOTT
HYDROLOGY...HARRIGAN
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
511 AM EST SAT JAN 9 2016
.DISCUSSION...
TODAY...A STRONGER AND DEEPER SHORT WAVE TROUGH THAN WE HAVE SEEN
THIS SEASON WILL PUSH FROM THE SOUTHERN PLAINS THIS MORNING TO THE
NORTHEAST STATES SUNDAY. THE SOUTHERN STREAM JET AXIS NOSING INTO
THE WESTERN GULF OF MEXICO TODAY WILL LIFT STEADILY INTO THE
SOUTHEAST STATES. THIS WILL KEEP THE MAIN LARGE SCALE ASCENT NORTH
OF OUR AREA AS THE ASSOCIATED SFC LOW OVER THE SOUTHERN MS VALLEY
DEEPENS AND MOVES INTO THE EASTERN GREAT LAKES SUNDAY MORNING.
THE GFS SHOWS SOME CLUSTERS OF CONVECTION OVER THE GULF OF MEXICO
AHEAD OF THE APPROACHING COLD FRONT BUT ITS MODEL QPF AND MOS
POPS ARE 10 PERCENT OR LESS NOT ONLY TODAY BUT ALSO TONIGHT. THE
ECMWF IS ALSO MOSTLY DRY FOR TODAY BUT SHOWS 20 POP FOR LEE AND
BRINGS 40 POP ACROSS THE AREA TONIGHT. THE ATMOS DOES HAS SOME
MOISTENING TO DO BUT AS WE SAW RECENTLY...IT CAN MOISTEN QUICKLY.
THE HRRR MODEL CONTINUES TO SHOW RAPID EASTWARD MOVEMENT OF PRECIP
SHIELD REACHING LAKE COUNTY AROUND SUNSET AND METRO ORLANDO/I 4
CORRIDOR EARLY IN THE EVE. HAVE LEANED TOWARD THIS SOLUTION IN POP
DISTRIBUTION SHOWING RAIN FREE CONDITIONS MOST OF THE DAY ALL
AREAS THEN SCATTERED SHOWERS I 4 CORRIDOR EARLY IN THE EVE.
THE OTHER FORECAST CHALLENGE IS PROSPECT FOR THUNDER. DESPITE
ABOVE NORMAL TEMPERATURES IN THE LOWER 80S...CONSIDERABLE
CLOUDINESS AND WEAK DESTABILIZATION WILL COMBINE WITH TIMING OF
BEST PRECIP CHANCES TO LIMIT DEEP CONVECTION TO AN EXTENT. THE
BEST CHANCE MAY OCCUR LATE TODAY/EARLY THIS EVE AS INITIAL
CONVECTION PUSHES ONSHORE THE FL GULF COAST. SO HAVE DRAWN A
SLIGHT CHANCE FOR THUNDER INITIALLY IN LAKE COUNTY AND GRADUALLY
SPREAD THAT SLIGHT CHANCE ACROSS THE REMAINDER OF EC FL THE REST
OF THE EVE. BUT THREAT FOR THUNDER LOOKS TOO LOW TO MENTION AFTER
MIDNIGHT. RISK OF SEVERE STORMS APPEARS VERY LOW.
SUN-MON...NEARLY ZONAL (WSW) FLOW ALOFT DURING THIS PERIOD AS
SHORTWAVE ENERGY REMAINS CONFINED TO THE GULF COAST STATES AND
FURTHER NORTH. A COLD FRONT OVER CENTRAL FL EARLY IN THE PERIOD WILL
CONTINUE TO ADVANCE SOUTHEAST AND FINALLY EAST OF THE AREA BY
AFTERNOON. NORTHWEST WINDS AROUND 15 MPH WILL FOLLOW THE BOUNDARY AS
HIGH PRESSURE BUILDS INTO THE DEEP SOUTH THROUGH THE PERIOD. THERE
MAY BE ISOLD-SCT SHOWERS SOUTH OF A LINE FROM NEAR TITUSVILLE-
KISSIMMEE ON SUN BUT CONDITIONS SHOULD GRADUALLY IMPROVE FROM NORTH
TO SOUTH DURING THE DAY. MAINLY DRY CONDITIONS FORECAST SUN NIGHT-
MON EVENING...EXCEPT POTENTIALLY LATE NIGHT SHOWERS MON OVERNIGHT
OVER THE TREASURE COAST AS THERE MAY BE SOME RETURN MOISTURE HERE.
HIGHS ON SUN SHOULD RECOVER INTO THE L-M70S ALONG/NORTH OF I-
4...EXCEPT U70S TO AROUND 80 DEGREES SOUTH OF HERE. LOWS ON SUN
NIGHT COMING IN COOLER NOW AND IN THE 40S...EXCEPT L50S ALONG THE
IMMEDIATE SAINT LUCIE/MARTIN COASTS. IF WINDS WERE TO REMAIN A BIT
MORE ELEVATED EXPECT THESE LOWS TO BE A BIT HIGHER. HIGHS ON MON
COOLER AND MAINLY IN THE 60S AREAWIDE. CHILLY AGAIN MON NIGHT WITH
SIMILAR TEMPERATURES AS THE PREVIOUS NIGHT.
TUE-FRI...THE SOUTHERN JET STREAM REMAINS FAIRLY ACTIVE THROUGH THE
PERIOD WITH WINDS OF 120-150KTS ACROSS THE REGION AT 250MB. NEARLY
ZONAL FLOW WILL EXIST AT 500MB THROUGH THE PERIOD THOUGH SHORTWAVE
IMPULSES WILL BE FEW ACROSS THE AREA INTO EARLY THU. REINFORCING
HIGH PRESSURE WILL MOVE DOWN INTO THE DEEP SOUTH ON WED...INTO THE
SOUTHEAST U.S. WED OVERNIGHT AND QUICKLY OFF OF THE COAST INTO THE
WESTERN ATLC ON THU.
WHILE TIMING/PLACEMENT OF FEATURES ARE NOT PRESENTLY CONSISTENT BOTH
THE GFS/ECMWF NOW HINT AT THE NEXT WEATHER SYSTEM ORGANIZING ACROSS
SOUTH TEXAS/WESTERN GULF WED OVERNIGHT AND MOVING ALONG THE GULF
COAST DURING THE DAY ON THU AND ACROSS THE FLORIDA PENINSULA THU
NIGHT/EARLY FRI. SOME POTENT SHORTWAVE ENERGY IS ALSO CURRENTLY
FORECAST TO ACCOMPANY THIS SYSTEM. IF THIS WERE TO HOLD TRUE THE
WIND FIELD AHEAD OF THIS SYSTEM COULD MAKE CONVECTION INTERESTING
THU OVERNIGHT. HOWEVER...COOLER TEMPERATURES/LOW MOISTURE RETURN
WOULD LIMIT THE OVERALL INSTABILITY. THE EXTENDED RANGE HAS BEEN
ANYTHING BUT CONSISTENT SO WILL CONTINUE TO MONITOR FOR NOW.
ANY AIRMASS MODIFICATION THAT MAY TAKE PLACE LOOKS MORE LIKELY
ACROSS THE SOUTH SO CONTINUE SCHC/CHC POPS TUE-TUE EVENING ACROSS
MAINLY THE TREASURE COAST/OKEECHOBEE COUNTY. THE MUCH COOLER AIR
BEHIND THE LATEST FRONT WILL CONTINUE IN PLACE INTO THE EXTENDED AS
FORECAST HIGHS/LOWS REMAIN WELL BELOW CLIMO THRU THU AND THEN CLOSER
TOWARDS NORMAL BY FRI.
&&
.AVIATION...
TAF SUITE SHOWS ALL TERMINALS BECOMING LIFR/VLIFR VV002-006
THROUGH 14Z WITH PATCHY DENSE FOG REDUCING VSBYS BELOW 1 MILE IN
SPOTS. LINGERING MVFR/IFR STRATUS FOR 2HRS OR SO THEREAFTER THEN
BECOMING VFR BY 17Z. MOST OF THE DAY SHOULD BE RAINFREE WITH A
CHANCE FOR SHOWERS AFT 21Z AT LEE SPREADING EAST TO MCO/DAB
THROUGH 02Z AND REMAINING TERMINALS THROUGH 06Z AND BEYOND. THREAT
FOR THUNDER LOOKS LOW BUT BEST CHANCE WILL BE LEE LATE IN THE DAY.
&&
.MARINE...
TODAY/TONIGHT...LOW PRESSURE IS FORECAST TO LIFT NE FROM THE
LOWER MS VALLEY AND STRENGTHEN AS IT REACHES THE EASTERN GREAT
LAKES TONIGHT. A WEAK INVERTED TROUGH ANALYZED JUST OFFSHORE THE
FL EAST COAST WILL PRODUCE A LIGHT NORTH FLOW ALONG THE COAST THIS
MORNING. BUT WINDS WILL SHIFT OUT OF THE S TO SW LATER THIS
MORNING AND AFTERNOON AS AN APPROACHING SYSTEM RAPIDLY MOVES EAST
FROM THE GULF OF MEXICO. WIND SPEEDS WILL BE AROUND 10 KNOTS THIS
AFTERNOON BUT INCREASE 15-20 KNOTS OFFSHORE TONIGHT AHEAD OF A
COLD FRONT. RAIN CHANCES LOOK QUITE LOW OVER THE ATLC WATERS
DURING THE DAY BUT FAST MOVING SHOWERS WILL APPROACH FROM THE WEST
BY EARLY EVENING INTO THE OVERNIGHT.
SUN-WED...THE LATEST WEATHER SYSTEM OVER THE CENTRAL PENINSULA EARLY
IN THE PERIOD WILL FINALLY CLEAR THE COASTAL WATERS BY LATE IN THE
DAY OR EARLY SUN EVENING. SCATTERED SHOWERS MAY CONTINUE IN THE
FORECAST SOUTH OF SEBASTIAN INLET ON SUN. CENTER OF HIGH PRESSURE
BUILDS INTO THE REGION SUN NIGHT THRU WED AND REMAINS NORTH OF THE
AREA. WE MAY SEE AN INTRO FOR SHOWERS BACK IN THE FORECAST MON
OVERNIGHT-TUE EVENING WITH SOME RETURN MOISTURE SOUTH OF SEBASTIAN
INLET.
WRLY WINDS BECOMING NWRLY ON SUN BEHIND THE FRONT WITH SPEEDS 14-
18KTS OVER THE OPEN ATLC. THE PRESSURE GRADIENT RELAXES ON MON AS
WINDS VEER MORE NORTHERLY AND SPEEDS DECREASE. WILL CONTINUE TO SEE
A N/NW WIND DIRECTION THROUGH THE EXTENDED. A PERSISTENT ENE LONG
PERIOD SWELL WILL KEEP SMALL CRAFT BOATING CONDITIONS POOR WITH
POTENTIAL HAZARDOUS CONDITIONS NEAR INLETS DURING THE OUTGOING TIDE.
THRU MON NIGHT SEAS WILL AVERAGE 5-6FT...POSSIBLY 7FT OFFSHORE/GULF
STREAM AND 3-5FT PERHAPS 4-6FT WITHIN 20NM OF THE COAST. LATE MON
NIGHT INTO WED MAY FINALLY SEE ANOTHER FOOT OR TWO DROP OFF OF THESE
WAVE HEIGHTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 78 62 73 43 / 30 40 10 0
MCO 80 64 77 45 / 30 40 10 0
MLB 80 66 79 46 / 20 40 20 0
VRB 81 66 80 49 / 20 40 30 10
LEE 79 63 73 44 / 40 40 10 0
SFB 80 63 74 44 / 30 40 10 0
ORL 81 65 75 48 / 30 40 10 0
FPR 81 66 80 49 / 20 40 30 10
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
SHORT TERM...KELLY
LONG TERM....SEDLOCK
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
534 AM EST SAT JAN 9 2016
.SYNOPSIS...
ISSUED AT 1245 AM EST SAT JAN 9 2016
RAIN WILL MOVE BACK INTO THE AREA THIS AFTERNOON AND THEN
TRANSITION TO SNOW FROM WEST TO EAST THROUGH THE EVENING AND
OVERNIGHT HOURS. THE GREATEST POTENTIAL FOR HEAVY SNOW AND SEVERAL
INCHES OF ACCUMULATION REMAINS CLOSER TO LAKE MICHIGAN. FURTHER
EAST...AMOUNTS WILL BE LIGHTER BUT THEY WILL DEPEND ON THE TIMING
OF CHANGEOVER FROM RAIN TO SNOW. TEMPERATURES WILL FALL QUICKLY
TONIGHT LEADING TO A QUICK FREEZE OF WET SURFACES. WINDS WILL ALSO
INCREASE LATE TONIGHT INTO SUNDAY CREATING BLOWING AND DRIFTING
SNOW.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 529 AM EST SAT JAN 9 2016
OBVIOUS FOCUS FOR THIS SHORT TERM FORECAST IS TRANSITION FROM RAIN
TO SNOW LATE TODAY AND AMOUNTS. HAVE ISSUED WINTER STORM WARNING FOR
FAR NORTHWEST COUNTIES WITH WINTER WEATHER ADVISORY TO THE EAST OF
THE WARNING.
PHASING OF NORTHERN AND SOUTHERN STREAM SHORT WAVES TO TAKE PLACE
THIS PERIOD AND WATER VAPOR SHOWS THE TWO PLAYERS OF INTEREST
BEGINNING TO COME TOGETHER. NORTHERN STREAM WAVE IS DROPPING INTO
THE NORTHERN CONUS THIS MORNING WHILE SOUTHERN STREAM SYSTEM IS
BEGINNING TO LIFT OUT OF TEXAS. THIS WILL INITIALLY SPREAD RAIN
NORTHWARD ACROSS THE AREA THIS AFTERNOON. RAIN AND SNOW MIX EXPECTED
LATE AFTERNOON IN FAR NORTHWEST WHILE ALL RAIN CENTRAL AND EAST
UNTIL TONIGHT. SFC TEMPS INITIALLY ABOVE FREEZING SO LITTLE TO NO
ACCUMULATION EXPECTED UNTIL THIS EVENING.
MODELS IN RATHER GOOD AGREEMENT FOR COMPLEXITY OF PHASING WITH
PRIMARY DIFFERENCES BEING STRENGTH OF PHASED LOW AND HOW FAST COLD
AIR MOVES IN LOCALLY FOR CHANGEOVER TO SNOW LATE TODAY. 150+ KT 250-
300MB JET WILL DEVELOP TONIGHT FROM THE GULF COAST INTO THE TN
VALLEY REGION. LEFT EXIT REGION TO PROVIDE UPPER LEVEL DIFFLUENCE TO
AID IN DEEPENING SFC LOW WHICH SHOULD LIFT NORTHEAST FROM ARKANSAS
TO SOUTHERN INDIANA AND INTO NORTH CENTRAL OHIO BY SUNDAY MORNING.
MODEL CLUSTERS ARE RATHER TIGHT SO CONFIDENCE HIGH IN THIS GENERAL
TRACK.
THE PROBLEM LIES WITH HOW FAST LOW WILL DEEPEN AND HOW QUICK COLD
AIR WILL INFILTRATE CWA TO CHANGE PCPN OVER TO SNOW. NAM12 GENERALLY
THE QUICKEST WHILE MOST OTHER MODEL SOLUTIONS ARE SLOWER WITH THE
COLD AIR AND COMPLETE CHANGEOVER. TYPICALLY MODELS ARE TOO SLOW WITH
ARCTIC AIR INTRUSION AND 2M TEMPS UPSTREAM OVERNIGHT HAVE BEEN
LAGGING SFC OBS BY A FEW DEGREES SO GIVING SOME WEIGHT TO THE COLDER
NAM THERMAL PROFILES DESPITE ITS OVERALL WEAKER SOLUTION. WHILE
850MB TEMPS DROP BELOW 0C LATE THIS AFTERNOON...MOST MODELS KEEPING
A PBL MAX TEMP OF 3 TO 4C THROUGH 03Z IN THE NORTHWEST WITH SFC
TEMPS IN THE 33-36F RANGE. HAVE ADJUSTED THESE DOWN A COUPLE DEGREES
USING BLEND OF NAM AND GFS TO ALLOW FOR CHANGEOVER TO ALL SNOW
SHORTLY AFTER 00Z WITH DYNAMIC COOLING FROM STRONG LIFT IN
DEFORMATION ZONE AIDING IN CHANGEOVER. SFC TEMPS INITIALLY ABOVE
FREEZING AND WET GROUND FROM AFTERNOON RAIN MAY INHIBIT ACCUMS
INITIALLY UNTIL DEEPER COLD WEDGE ARRIVES IN THE NORTHWEST BY 03Z
WITH MODERATE SNOWFALL EXPECTED FOR SEVERAL HOURS OVERNIGHT.
USED A BLEND OF NAM12 AND GFS SNOW RATIOS IN TOP DOWN METHOD ALONG
WITH WPC QPF TO ARRIVE AT SNOWFALL AMOUNTS. AGAIN...TRICKY WITH PBL
TEMPS SO AMOUNTS COULD STILL VARY DEPENDING ON TIMING OF CHANGEOVER.
CONFIDENCE FOR WARNING AIDED BY EXPECTED LAKE ENHANCEMENT LATE
TONIGHT ALONG WITH STRONG WINDS AND FREEZING TEMPS MAKING FOR ICY
ROADS. THE BLEND YIELDED GENERAL AMOUNTS OF 4-7 INCHES IN THE FAR
NORTHWEST WHERE WARNING WAS ISSUED.
AWAY FROM THE WARNING...AMOUNTS OF 2 TO 5 EXPECTED WITH SIMILAR WIND
AND FREEZING ROAD CONCERNS SO ISSUED WINTER WEATHER ADVISORY. THIS
MAY NEED TO BE EXPANDED EAST FOR SUNDAY BUT WITH LESS AMOUNTS
GENERALLY EAST OF US 31 AND MORE IMPACTS IN THE LATE 2ND AND 3RD
PERIODS OPTED TO HOLD OFF ON SPREADING ADVISORY ANY FARTHER EAST.
CHANGEOVER TO SNOW WILL BE LATER TONIGHT AND LATEST GUIDANCE KEPT
EXTREME EASTERN COUNTIES AS RAIN TIL 12Z SUNDAY.
&&
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 529 AM EST SAT JAN 9 2016
TRANSITION TO ALL SNOW SHOULD BE COMPLETE AT THE START OF THE PERIOD
AS ARCTIC AIR POURS IN ON STRONG NW WINDS. LAKE ENHANCED SNOW
SHOWERS SHOULD PENETRATE WELL INLAND RESULTING NEED FOR INCREASE IN
POPS THROUGH THE DAY FURTHER EAST AND SOUTH. MOST LOCATIONS SHOULD
SEE ANYWHERE FROM A DUSTING TO UP TO AN INCH WITH LOCATIONS CLOSER
TO THE LAKE IN THE WARNING AREA POTENTIALLY SEEING LOCALLY MORE. THE
STRONG WINDS WILL ALLOW FOR EFFICIENT BLOWING AND DRIFTING OF THE
SNOW ALL DAY IN THE HEADLINE AREAS AND EXPANDING TO SOUTHEAST HALF
OR SO DURING THE AFTERNOON AS TEMPS FALL THROUGH THE 20S AND THE
SNOW BECOMES EASIER TO PICK UP. LATER SHIFTS MAY NEED TO EXPAND
ADVISORY FURTHER EAST THAN CURRENTLY IN PLACE DEPENDING ON FINAL
LAYOUT OF HEAVIEST SNOW...ADDITIONAL ACCUMULATIONS ON SUNDAY AND MAX
WIND SPEEDS.
LOW LEVEL FLOW WILL BRIEFLY BECOME WEST AND EVENTUALLY SOUTHWEST
SUNDAY NIGHT INTO MONDAY AHEAD OF THE NEXT SYSTEM..ALLOWING THE SNOW
SHOWERS TO SHIFT MORE INTO MI. CLIPPER SYSTEM WILL DROP INTO THE
AREA MONDAY NIGHT INTO TUESDAY AND BRING INCREASING CHANCES FOR
LIGHT SNOW TO THE AREA. LAKE EFFECT WILL BECOME RENEWED AS
COMBINATION OF EVEN COLDER AIR...INCREASE IN SYNOPTIC MOISTURE AND
INVERSION HEIGHTS AND MORE FAVORABLE FETCH ALL COMBINE.
THE CHANCE FOR SNOW SHOWERS WILL LINGER THROUGH THE REMAINDER OF THE
PERIOD AS COLD AIR CONTINUES TO REMAIN ENTRENCHED..ALTHOUGH SOME
MODERATION INTO THE MIDDLE AND UPPER 20S LOOKS POSSIBLE TOWARDS THE
END OF THE WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1244 AM EST SAT JAN 9 2016
AVIATION FORECAST BECOMING TRICKY AS MIXING WITHIN WARM SECTOR HAS
ERODED LOW CIGS NEAR KFWA WHILE KSBN REMAINS CLOSER TO FRONTAL
BOUNDARY AND LIFR CONDITIONS. HIRES GUIDANCE DOES NOT HAVE A GOOD
HANDLE ON THESE CONDITIONS BUT HRRR IS TRENDING TOWARD MVFR AND
VFR AT KFWA WITH KSBN IN AND OUT OF THE LOW STRATUS. HAVE KEPT
KSBN IN THE LOWER CIGS WITH TRAJECTORIES SUGGESTING LOW CLOUDS MAY
NOT LIFT OUT. WITH VFR UPSTREAM OF KFWA HAVE BEEN A BIT MORE
OPTIMISTIC THERE. CONDITIONS DETERIORATE AGAIN SATURDAY AS NEXT
WAVE LIFTS NORTH AND FRONTAL BOUNDARY SAGS FURTHER EAST. PCPN TO
DEVELOP AFTER 20Z WITH KFWA LIKELY REMAINING RAIN UNTIL VERY END
OF PERIOD WHILE KSBN LIKELY STARTS AS A RAIN AND SNOW MIX WITH
QUICK TRANSITION TO ALL SNOW TOWARD 00Z AND VLIFR CONDITIONS.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...WINTER STORM WARNING FROM 7 PM EST /6 PM CST/ THIS EVENING TO 7
PM EST /6 PM CST/ SUNDAY FOR INZ003-004.
WINTER WEATHER ADVISORY FROM 7 PM EST /6 PM CST/ THIS EVENING TO
7 PM EST /6 PM CST/ SUNDAY FOR INZ012>015-020-022.
WINTER WEATHER ADVISORY FROM 10 PM THIS EVENING TO 7 PM EST
SUNDAY FOR INZ005-006-016.
MI...WINTER STORM WARNING FROM 7 PM THIS EVENING TO 7 PM EST SUNDAY
FOR MIZ077-078.
WINTER WEATHER ADVISORY FROM 10 PM THIS EVENING TO 7 PM EST
SUNDAY FOR MIZ079-080.
OH...NONE.
LM...GALE WARNING FROM 11 PM THIS EVENING TO 7 PM EST SUNDAY FOR
LMZ043-046.
&&
$$
SYNOPSIS...LASHLEY
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
1252 AM EST SAT JAN 9 2016
.SYNOPSIS...
ISSUED AT 1245 AM EST SAT JAN 9 2016
RAIN WILL MOVE BACK INTO THE AREA LATE THIS AFTERNOON AND THEN
TRANSITION TO SNOW FROM WEST TO EAST THROUGH THE EVENING AND
OVERNIGHT HOURS. THE GREATEST POTENTIAL FOR HEAVY SNOW AND SEVERAL
INCHES OF ACCUMULATION REMAINS ACROSS THE NORTHWEST CLOSER TO LAKE
MICHIGAN. FURTHER EAST...AMOUNTS WILL BE LIGHTER BUT WILL DEPEND
ON THE TIMING OF CHANGEOVER FROM RAIN TO SNOW. TEMPERATURES WILL
FALL QUICKLY TONIGHT LEADING TO A QUICK FREEZE OF WET SURFACES.
WINDS WILL ALSO INCREASE SUNDAY CREATING BLOWING AND DRIFTING
SNOW.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 351 PM EST FRI JAN 8 2016
ANOTHER BATCH OF RAIN (MORE SHOWERY IN NATURE WHEN COMPARED WITH
WHAT FELL EARLIER TODAY) WILL PIVOT THROUGH THIS EVENING INTO THE
EARLY OVERNIGHT AS A WELL DEFINED VORT MAX AND POCKET OF STEEPER
MID LEVEL LAPSE RATES LIFT NORTHEAST THROUGH THE LOWER LAKES.
TRAILING FRONTAL BOUNDARY THEN SETTLES IN TONIGHT INTO SATURDAY.
FORCING WANES WITH WEAK HEIGHT RISES IN BETWEEN UPPER LEVEL
WAVES...BUT STILL CANNOT RULE OUT A FEW LIGHT SHOWERS AND PATCHY
DRIZZLE IN THE VICINITY OF THIS FEATURE GIVEN AMPLE BOUNDARY LAYER
MOISTURE. AREAS OF FOG WILL ALSO REMAIN POSSIBLE THROUGH SATURDAY
MORNING ACROSS MAINLY NNW ZONES CLOSER TO SFC TROUGH.
MILD/OVERCAST OTHERWISE WITH RAIN LIKELY FILLING BACK IN ACROSS
WESTERN ZONES LATE SATURDAY AFTERNOON.
&&
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 351 PM EST FRI JAN 8 2016
SHRTWV ROUNDING BASE OF SWRN CONUS TROF TODAY WILL LIFT NE FROM THE
SRN PLAINS SATURDAY AND THROUGH THE OHIO VALLEY SATURDAY NIGHT WITH
ASSOCIATED SFC LOW MOVG FROM THE SRN PLAINS TO THE LWR GRTLKS
CAUSING RAIN CHANGING TO SNOW ACROSS OUR AREA. FCST TRACK FAVORS
EARLIER CHANGEOVER... HEAVIER SNOW IN 3-5" RANGE NW, TAPERING OFF TO
<1" SE. SNOW WILL BE HEAVY/WET INITIALLY PREVENTING
BLOWING/DRIFTING... BUT AS COLDER AIR ARRIVES AND WINDS PICK UP LATE
SAT NGT AND SUN AREAS OF BLOWING/DRIFTING SNOW EXPECTED ACROSS THE
NW PORTION OF CWA WHERE HEAVIEST ACCUMS OCCUR AND LES DVLPS. QUICK
TEMP DROP SAT NGT/SUNDAY WILL ALSO PROMOTE ICY ROAD CONDITIONS AS
MELTED SNOW REFREEZES. TOTAL SNOW ACCUMS BY SUNDAY EVE EXPECTED IN
THE 3-7" RANGE NW 1/3 OF CWA... HEAVIEST FAR NW IN COUNTIES NEAR
LAKE MICHIGAN. THIS IS MARGINAL FOR WARNING TYPE ACCUMS... BUT GIVEN
EXPECTATION OF STRONG WINDS AND FALLING TEMPS ISSUED A WINTER STORM
WATCH FOR THE NW FOR THIS TIME FRAME.
DEEP CLOSED LOW FORMING OVER SERN CANADA BY EARLY NEXT WEEK
EXPECTED TO MOVE VERY LITTLE DURING THE WEEK RESULTING IN BLO NORMAL
TEMPS ACROSS OUR AREA WHICH COMBINED WITH W-NW FLOW WILL RESULT
PERSISTENT LES NW... ENHANCED AROUND TUE AND THU BY SHRTWVS MOVG
THROUGH THE BASE OF THE TROF ACROSS THE GRTLKS. MEDIUM RANGE MODELS
HAVE HAD POOR RUN-RUN CONTINUITY ON HOW LONG THIS PATTERN WILL
PERSIST WITH 00Z RUNS SUGGESTING IT WOULD BREAK DOWN BY NEXT WEEKEND
AND LATEST RUNS KEEPING THE COLD AIR IN LONGER. COMPROMISED WITH A
SLOW CLIMB IN TEMPS FRI-SAT... BUT CONFIDENCE ON WARM-UP LATE IN THE
PERIOD IS LOW.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1244 AM EST SAT JAN 9 2016
AVIATION FORECAST BECOMING TRICKY AS MIXING WITHIN WARM SECTOR HAS
ERODED LOW CIGS NEAR KFWA WHILE KSBN REMAINS CLOSER TO FRONTAL
BOUNDARY AND LIFR CONDITIONS. HIRES GUIDANCE DOES NOT HAVE A GOOD
HANDLE ON THESE CONDITIONS BUT HRRR IS TRENDING TOWARD MVFR AND
VFR AT KFWA WITH KSBN IN AND OUT OF THE LOW STRATUS. HAVE KEPT
KSBN IN THE LOWER CIGS WITH TRAJECTORIES SUGGESTING LOW CLOUDS MAY
NOT LIFT OUT. WITH VFR UPSTREAM OF KFWA HAVE BEEN A BIT MORE
OPTIMISTIC THERE. CONDITIONS DETERIORATE AGAIN SATURDAY AS NEXT
WAVE LIFTS NORTH AND FRONTAL BOUNDARY SAGS FURTHER EAST. PCPN TO
DEVELOP AFTER 20Z WITH KFWA LIKELY REMAINING RAIN UNTIL VERY END
OF PERIOD WHILE KSBN LIKELY STARTS AS A RAIN AND SNOW MIX WITH
QUICK TRANSITION TO ALL SNOW TOWARD 00Z AND VLIFR CONDITIONS.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...WINTER STORM WATCH FROM THIS EVENING THROUGH SUNDAY EVENING FOR
INZ003>006-012>014.
MI...WINTER STORM WATCH FROM THIS EVENING THROUGH SUNDAY EVENING FOR
MIZ077>080.
OH...NONE.
LM...GALE WARNING FROM 11 PM THIS EVENING TO 7 PM EST SUNDAY FOR
LMZ043-046.
&&
$$
SYNOPSIS...LOTHAMER
SHORT TERM...STEINWEDEL
LONG TERM...JT
AVIATION...LASHLEY
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AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1143 PM CST FRI JAN 8 2016
...AVIATION UPDATE...
.UPDATE...
ISSUED AT 1119 PM CST FRI JAN 8 2016
VISIBILITIES HAVE IMPROVED TO NO LOWER THAN 1/2 MILE ON
OBSERVATIONS IN NW IL AS W TO NW WINDS BEGIN TO RAMP UP IN THE
TIGHTENING SURFACE PRESSURE GRADIENT. HAVE THUS CANCELLED THE
REMAINING DENSE FOG ADVISORY.
&&
.SYNOPSIS...
ISSUED AT 344 PM CST FRI JAN 8 2016
LATEST SFC ANALYSIS WAS INDICATING A LOW CENTER MOVING NORTHWARD
ACRS THE WEST CENTRAL DVN CWA ATTM...WITH A ASSOCIATED FRONTAL
SYSTEM TRAILING DOWN INTO SOUTHWESTERN AR AND NORTHERN TX. THE UPPER
LEVEL LOW WAS NOTED ON WATER VAPOR IMAGERY ACRS NORTHEASTERN MO INTO
THE SOUTHERN CWA...WITH A STRONGER WAVE FURTHER UPSTREAM IN A L/W
TROF BASE DIGGING TOWARD WESTERN TX.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 344 PM CST FRI JAN 8 2016
TONIGHT...ASSESSING THE LATEST TRENDS AND LLVL CONVERGENT FLOW
PROPAGATION ASSOCIATED WITH THE PASSING SFC WAVE...HAVE EXTENDED THE
FOG ADVISORY TO 03Z /9 PM CST/ FOR THE WESTERN 2/3S...AND THE
NORTHWESTERN IL COUNTIES NOW INCLUDING THE EASTERN I80 CORRIDOR TIL
06Z /MIDNIGHT CST/. BUT THESE END TIMES MAY BE A BIT GENEROUS AND
THE FOLLOWING SHIFT WILL BE ABLE TO CHOP AWAY FROM THE WEST AND
SOUTH AS THE EVENING PROGRESSES...AS THE LLVL FLOW VEERS TO THE
WEST/NORTHWEST AND INCREASES. LATEST RUN HRRR VSBY PROGS NOW SHIFT
THE 1/4 MILE OR LESS VSBYS EAST OF THE MS RIVER BY 03Z THIS
EVENING.
LINGERING AREAS OF RAIN AND DRIZZLE THIS AFTERNOON AND EARLY EVENING
TO ROLL OFF TO THE NORTHEAST...WITH JUST SPOTTY LIGHTER PRECIP
WRAPPING IN BEHIND THE DEPARTING CYCLONE OUT OF NORTHWESTERN IA.
WITH POST-FRONTAL TOP DOWN COOLING...THIS PRECIP TO CHANGE OVER TO A
LIGHT RAIN/SNOW MIX THEN TO ALL LIGHT WET SNOW OVERNIGHT FROM WEST
TO EAST. LINGERING MILD GROUND TEMPS AND LACK OF PRECIP INTENSITY
SUGGESTS A WET DUSTING TO A TENTH OF AN INCH AT BEST IN AREAS THAT
GET IN ON SOME SNOW LATER TONIGHT. NORTHWEST WINDS TO RAMP UP AFTER
MIDNIGHT TO 15 TO 25 MPH IN INCOMING CANADIAN HIGH PRESSURE GRADIENT
ESPECIALLY ALONG AND WEST OF THE MS RIVER. LLVL COLD CONVEYOR TO
BE WELL IN FLUX ACRS THE AREA BY SAT MORNING.
SATURDAY...12 HR HIGH TEMPS TO OCCUR IN THE MORNING WITH FALLING
TEMPS THRU THE REST OF THE DAY. TIGHT PRESSURE GRADIENT AND STRONG
LLVL COLD AIR ADVECTION TO DIVE BRISK NORTHWEST SFC WINDS OF 15 TO
25+ MPH AND GUSTS WELL OVER 30 MPH AT TIMES. SOME LIGHT SNOW SHOWERS
OR FLURRIES MAY GET WRUNG OUT OF ANY CLOUD DECK WITH ENOUGH
SATURATED DEPTH IN THIS CAA PROCESS ESPECIALLY NORTH OF I80 BUT
LITTLE IF ANY SNOW ACCUM EXPECTED WITH THIS ACTIVITY. THEN ALL EYES
TURN TO THE MAIN SOUTHERN PLAINS LOW PRESSURE WAVE EJECTING
NORTHEASTWARD TOWARD THE MOUTH OF THE OH RIVER VALLEY BY SAT
EVENING. BULK OF THE 12Z RUN MODEL SOLUTIONS HAVE CAUGHT ON TO THE
CURRENT STRONGER SOUTHEASTWARD DIGGING PROCESS OF THE WAVE AIDED
BY UPPER JET PUNCH IN THAT DIRECTION ON IT/S WESTERN FLANK. THUS
THEY HAVE CONTINUED TO TREND FURTHER SOUTHEAST WITH THE MAIN STORM
PROPAGATION PATH. WILL ADJUST SNOW AMOUNTS ON ITS FAR NORTHWESTERN
FLANK OF IT/S DEF ZONE FURTHER DOWN AND EAST AS WELL WITH THE
LATEST THINKING. THIS ONLY PRODUCES UP TO AN INCH OF SNOW BY 00Z
SUNDAY SOUTHEAST OF A LINE GENERALLY FROM SOUTHWEST OF MACOMB
IL...TO PRINCETON IL. FURTHER WEST TOWARD THE MS RIVER MAY ONLY
GET A TENTH OR TWO...AND AREAS WEST OF THE MS RIVER MAY STAY DRY
BESIDES THE LIGHT SNOW/ FLURRIES POSSIBLE NORTH OF I80 GETTING
WRUNG OUT OF WRAP AROUND CLOUD DECK IN THE COLD AIR ADVECTION
PROCESS MENTIONED ABOVE. ANY FURTHER ADJUSTMENT EAST MEANS A NON-
EVENT/MISS FOR THE DVN CWA. ..12..
.LONG TERM...(SATURDAY NIGHT THROUGH NEXT FRIDAY)
ISSUED AT 344 PM CST FRI JAN 8 2016
COLD MID JANUARY WEATHER AND DRY TO MOSTLY DRY THROUGH LATE NEXT
WEEK.
LONG TERM FORECAST CONFIDENCE ASSESSMENT...GOOD OR ABOVE AVERAGE
WITH LIMITED SENSIBLE WEATHER ISSUES. MAIN CHALLENGES WILL BE BOUTS
OF FLURRIES AND POSSIBLY VERY LIGHT SNOW ON MONDAY/MONDAY NIGHT AND
AGAIN LATE NEXT WEEK. OTHERWISE...DIURNAL RANGE OF TEMPERATURES
WITH POSSIBLY SOME NEGATIVE FEEDBACK FROM GREATLY REDUCE SNOW/ICE
FIELDS.
OVERVIEW...INITIALIZATION AND VERIFICATION GOOD WITH LOW LEVEL
THERMAL AND MOISTURE FIELDS HANDLED WELL. UPSTREAM INITIALIZATION
SUGGESTS BOTH GFS AND HI-RES ECMWF GOOD AND A ADEQUATE BLEND OF
50/50 MIX OF THESE SOLUTIONS A GOOD STARTING POINT. VERIFICATION
SUGGEST AREAS WITH NO ICE/SNOW COVER HIGHS MAY BE UP TO 3 DEGREES
TOO COLD FOR LATER SHIFTS WHILE AND SNOW/ICE COVERED LOCATIONS COULD
SEE MINS UP TO 3 DEGREES COLDER THAN FORECAST.
SATURDAY NIGHT...ONCE AGAIN HAVE TRIMMED POPS AND SNOW/QPF TOTALS AS
SYSTEM MAY PASS TO OUR SOUTHEAST. LATER SHIFTS MAY BE ABLE TO
REMOVE POPS OVER ALL BUT LOCATIONS SOUTHEAST OF A MACOMB ILLINOIS
TO PRINCETON LINE THAT MAY STILL PICK UP TO AN INCH OF A WET SNOW.
CLEARING SHOULD ARRIVE AFTER 2 AM IN NW AND ENCOMPASS ALL BUT SE 1/3
AREA BY SUNRISE. THIS SHOULD ALLOW FOR MINS AROUND ZERO DEGREES NW
SECTION TO LOWER TEENS IN FAR SOUTHEAST 1/4 WHERE CLOUDS WILL BE
DELAYED TO CLEAR AFTER SUNRISE. LATEST TRENDS SUPPORTS WIND CHILL
VALUES WILL BE MARGINAL MEETING WIND CHILL ADVISORY CRITERIA TO
AROUND -20F FOR 2 TO 5 HOURS OVER NORTHWEST 3 TO 6 COUNTIES FOR
LATER SHIFTS TO ASSESS. NORTHWEST WINDS OF 15 TO 25+ MPH WILL
DIMINISH LATE TO 10 TO 20 MPH BY MORNING.
SUNDAY...CLEAR AND QUITE COLD WITH MODERATE NORTHWEST WINDS
CONTINUING AT 10 TO 20 MPH. HIGHS SHOULD STRUGGLE INTO THE UPPER
SINGLE SINGLE DIGITS NORTHWEST TO THE MID TEENS FAR SOUTHEAST
SECTIONS WITH WIND CHILLS MOSTLY AT OR BELOW ZERO. SUNDAY NIGHT
CLEAR AND COLD WITH LIGHT WESTERLY WINDS LATE KEEPING WIND CHILLS TO
5 TO 15 BELOW ZERO. LOWS SHOULD BE ZERO TO UPPER SINGLE DIGITS WITH
FAVORED LOW LYING LOCATIONS FALLING POSSIBLY BELOW ZERO FOR LATER
SHIFTS TO REASSESS.
MONDAY AND MONDAY NIGHT...PARTLY TO MOSTLY CLOUDY WITH DECENT RISK
OF FLURRIES OR VERY LIGHT SNOW AND NOT AS COLD WITH HIGHS INTO THE
20S AHEAD OF NEXT REINFORCING SHOT OF ARCTIC AIR. MINS 5 TO 15
ABOVE AS NEXT INVASION OF ARCTIC AIR ARRIVES TOWARD MORNING IN THE
NORTHWEST. WIND CHILLS FALLING TO 10 TO 20 BELOW ZERO BY TUESDAY
MORNING.
TUESDAY...CLEAR BLUSTERY AND COLD...SIMILAR TO SUNDAY WITH HIGHS 10
TO 20 ABOVE AND POSSIBLY A FEW DEGREES COLDER THAN THIS AND
NORTHWEST WINDS OF 20 TO 30 MPH AND LOW WIND CHILLS AT OR BELOW
ZERO. TUESDAY NIGHT...MINS ZERO TO 10 ABOVE AND POSSIBLY AT LEAST
3DEGREES COLDER FOR LATER SHIFTS WITH WIND CHILLS ONCE AGAIN TO FALL
TO NEAR 15 TO 20 BELOW NORTH OF I-80.
WEDNESDAY AND THURSDAY...DRY WITH A SLOW WARMING TREND WITH HIGHS
20S WEDNESDAY AND MOSTLY 30S ON THURSDAY. MINS MOSTLY 10 TO 20
ABOVE WEDNESDAY AM AND 20S THURSDAY AM.
FRIDAY...SEASONABLY COLD AND DRY WITH HIGHS NEAR NORMAL OR MID 20S
TO LOWER 30S AND MINS MOSTLY IN THE TEENS. NICHOLS
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1142 PM CST FRI JAN 8 2016
AN AXIS OF LIGHT SNOW OVER CENTRAL IA WILL MOVE EAST THROUGH THE
TERMINALS OVERNIGHT. OTHERWISE...LINGERING LOW CLOUDS AND SLOWLY
THINNING FOG WILL KEEP LIFR TO IFR CONDITIONS IN PLACE OVERNIGHT.
A TIGHTENING FLOW BETWEEN HIGH PRESSURE OVER THE NORTHERN PLAINS
AND LOW PRESSURE PASSING THROUGH THE OHIO VALLEY REGION WILL
CAUSE NORTHWEST WINDS TO INCREASE THROUGHOUT THE TAF PERIOD...WITH
SUSTAINED SPEEDS AROUND 15 TO 20 KTS BY LATE SATURDAY INTO
SATURDAY NIGHT. AT THE SAME TIME...CIGS WILL GRADUALLY
LIFT...LEADING TO AT LEAST MVFR CONDITIONS BY SATURDAY EVENING.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...SHEETS
SYNOPSIS...12
SHORT TERM...12
LONG TERM...NICHOLS
AVIATION...SHEETS
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1119 PM CST FRI JAN 8 2016
.UPDATE...
ISSUED AT 1119 PM CST FRI JAN 8 2016
VISIBILITIES HAVE IMPROVED TO NO LOWER THAN 1/2 MILE ON
OBSERVATIONS IN NW IL AS W TO NW WINDS BEGIN TO RAMP UP IN THE
TIGHENING SURFACE PRESSURE GRADIENT. HAVE THUS CANCELLED THE
REMAINING DENSE FOG ADVISORY.
&&
.SYNOPSIS...
ISSUED AT 344 PM CST FRI JAN 8 2016
LATEST SFC ANALYSIS WAS INDICATING A LOW CENTER MOVING NORTHWARD
ACRS THE WEST CENTRAL DVN CWA ATTM...WITH A ASSOCIATED FRONTAL
SYSTEM TRAILING DOWN INTO SOUTHWESTERN AR AND NORTHERN TX. THE UPPER
LEVEL LOW WAS NOTED ON WATER VAPOR IMAGERY ACRS NORTHEASTERN MO INTO
THE SOUTHERN CWA...WITH A STRONGER WAVE FURTHER UPSTREAM IN A L/W
TROF BASE DIGGING TOWARD WESTERN TX.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 344 PM CST FRI JAN 8 2016
TONIGHT...ASSESSING THE LATEST TRENDS AND LLVL CONVERGENT FLOW
PROPAGATION ASSOCIATED WITH THE PASSING SFC WAVE...HAVE EXTENDED THE
FOG ADVISORY TO 03Z /9 PM CST/ FOR THE WESTERN 2/3S...AND THE
NORTHWESTERN IL COUNTIES NOW INCLUDING THE EASTERN I80 CORRIDOR TIL
06Z /MIDNIGHT CST/. BUT THESE END TIMES MAY BE A BIT GENEROUS AND
THE FOLLOWING SHIFT WILL BE ABLE TO CHOP AWAY FROM THE WEST AND
SOUTH AS THE EVENING PROGRESSES...AS THE LLVL FLOW VEERS TO THE
WEST/NORTHWEST AND INCREASES. LATEST RUN HRRR VSBY PROGS NOW SHIFT
THE 1/4 MILE OR LESS VSBYS EAST OF THE MS RIVER BY 03Z THIS
EVENING.
LINGERING AREAS OF RAIN AND DRIZZLE THIS AFTERNOON AND EARLY EVENING
TO ROLL OFF TO THE NORTHEAST...WITH JUST SPOTTY LIGHTER PRECIP
WRAPPING IN BEHIND THE DEPARTING CYCLONE OUT OF NORTHWESTERN IA.
WITH POST-FRONTAL TOP DOWN COOLING...THIS PRECIP TO CHANGE OVER TO A
LIGHT RAIN/SNOW MIX THEN TO ALL LIGHT WET SNOW OVERNIGHT FROM WEST
TO EAST. LINGERING MILD GROUND TEMPS AND LACK OF PRECIP INTENSITY
SUGGESTS A WET DUSTING TO A TENTH OF AN INCH AT BEST IN AREAS THAT
GET IN ON SOME SNOW LATER TONIGHT. NORTHWEST WINDS TO RAMP UP AFTER
MIDNIGHT TO 15 TO 25 MPH IN INCOMING CANADIAN HIGH PRESSURE GRADIENT
ESPECIALLY ALONG AND WEST OF THE MS RIVER. LLVL COLD CONVEYOR TO
BE WELL IN FLUX ACRS THE AREA BY SAT MORNING.
SATURDAY...12 HR HIGH TEMPS TO OCCUR IN THE MORNING WITH FALLING
TEMPS THRU THE REST OF THE DAY. TIGHT PRESSURE GRADIENT AND STRONG
LLVL COLD AIR ADVECTION TO DIVE BRISK NORTHWEST SFC WINDS OF 15 TO
25+ MPH AND GUSTS WELL OVER 30 MPH AT TIMES. SOME LIGHT SNOW SHOWERS
OR FLURRIES MAY GET WRUNG OUT OF ANY CLOUD DECK WITH ENOUGH
SATURATED DEPTH IN THIS CAA PROCESS ESPECIALLY NORTH OF I80 BUT
LITTLE IF ANY SNOW ACCUM EXPECTED WITH THIS ACTIVITY. THEN ALL EYES
TURN TO THE MAIN SOUTHERN PLAINS LOW PRESSURE WAVE EJECTING
NORTHEASTWARD TOWARD THE MOUTH OF THE OH RIVER VALLEY BY SAT
EVENING. BULK OF THE 12Z RUN MODEL SOLUTIONS HAVE CAUGHT ON TO THE
CURRENT STRONGER SOUTHEASTWARD DIGGING PROCESS OF THE WAVE AIDED
BY UPPER JET PUNCH IN THAT DIRECTION ON IT/S WESTERN FLANK. THUS
THEY HAVE CONTINUED TO TREND FURTHER SOUTHEAST WITH THE MAIN STORM
PROPAGATION PATH. WILL ADJUST SNOW AMOUNTS ON ITS FAR NORTHWESTERN
FLANK OF IT/S DEF ZONE FURTHER DOWN AND EAST AS WELL WITH THE
LATEST THINKING. THIS ONLY PRODUCES UP TO AN INCH OF SNOW BY 00Z
SUNDAY SOUTHEAST OF A LINE GENERALLY FROM SOUTHWEST OF MACOMB
IL...TO PRINCETON IL. FURTHER WEST TOWARD THE MS RIVER MAY ONLY
GET A TENTH OR TWO...AND AREAS WEST OF THE MS RIVER MAY STAY DRY
BESIDES THE LIGHT SNOW/ FLURRIES POSSIBLE NORTH OF I80 GETTING
WRUNG OUT OF WRAP AROUND CLOUD DECK IN THE COLD AIR ADVECTION
PROCESS MENTIONED ABOVE. ANY FURTHER ADJUSTMENT EAST MEANS A NON-
EVENT/MISS FOR THE DVN CWA. ..12..
.LONG TERM...(SATURDAY NIGHT THROUGH NEXT FRIDAY)
ISSUED AT 344 PM CST FRI JAN 8 2016
COLD MID JANUARY WEATHER AND DRY TO MOSTLY DRY THROUGH LATE NEXT
WEEK.
LONG TERM FORECAST CONFIDENCE ASSESSMENT...GOOD OR ABOVE AVERAGE
WITH LIMITED SENSIBLE WEATHER ISSUES. MAIN CHALLENGES WILL BE BOUTS
OF FLURRIES AND POSSIBLY VERY LIGHT SNOW ON MONDAY/MONDAY NIGHT AND
AGAIN LATE NEXT WEEK. OTHERWISE...DIURNAL RANGE OF TEMPERATURES
WITH POSSIBLY SOME NEGATIVE FEEDBACK FROM GREATLY REDUCE SNOW/ICE
FIELDS.
OVERVIEW...INITIALIZATION AND VERIFICATION GOOD WITH LOW LEVEL
THERMAL AND MOISTURE FIELDS HANDLED WELL. UPSTREAM INITIALIZATION
SUGGESTS BOTH GFS AND HI-RES ECMWF GOOD AND A ADEQUATE BLEND OF
50/50 MIX OF THESE SOLUTIONS A GOOD STARTING POINT. VERIFICATION
SUGGEST AREAS WITH NO ICE/SNOW COVER HIGHS MAY BE UP TO 3 DEGREES
TOO COLD FOR LATER SHIFTS WHILE AND SNOW/ICE COVERED LOCATIONS COULD
SEE MINS UP TO 3 DEGREES COLDER THAN FORECAST.
SATURDAY NIGHT...ONCE AGAIN HAVE TRIMMED POPS AND SNOW/QPF TOTALS AS
SYSTEM MAY PASS TO OUR SOUTHEAST. LATER SHIFTS MAY BE ABLE TO
REMOVE POPS OVER ALL BUT LOCATIONS SOUTHEAST OF A MACOMB ILLINOIS
TO PRINCETON LINE THAT MAY STILL PICK UP TO AN INCH OF A WET SNOW.
CLEARING SHOULD ARRIVE AFTER 2 AM IN NW AND ENCOMPASS ALL BUT SE 1/3
AREA BY SUNRISE. THIS SHOULD ALLOW FOR MINS AROUND ZERO DEGREES NW
SECTION TO LOWER TEENS IN FAR SOUTHEAST 1/4 WHERE CLOUDS WILL BE
DELAYED TO CLEAR AFTER SUNRISE. LATEST TRENDS SUPPORTS WIND CHILL
VALUES WILL BE MARGINAL MEETING WIND CHILL ADVISORY CRITERIA TO
AROUND -20F FOR 2 TO 5 HOURS OVER NORTHWEST 3 TO 6 COUNTIES FOR
LATER SHIFTS TO ASSESS. NORTHWEST WINDS OF 15 TO 25+ MPH WILL
DIMINISH LATE TO 10 TO 20 MPH BY MORNING.
SUNDAY...CLEAR AND QUITE COLD WITH MODERATE NORTHWEST WINDS
CONTINUING AT 10 TO 20 MPH. HIGHS SHOULD STRUGGLE INTO THE UPPER
SINGLE SINGLE DIGITS NORTHWEST TO THE MID TEENS FAR SOUTHEAST
SECTIONS WITH WIND CHILLS MOSTLY AT OR BELOW ZERO. SUNDAY NIGHT
CLEAR AND COLD WITH LIGHT WESTERLY WINDS LATE KEEPING WIND CHILLS TO
5 TO 15 BELOW ZERO. LOWS SHOULD BE ZERO TO UPPER SINGLE DIGITS WITH
FAVORED LOW LYING LOCATIONS FALLING POSSIBLY BELOW ZERO FOR LATER
SHIFTS TO REASSESS.
MONDAY AND MONDAY NIGHT...PARTLY TO MOSTLY CLOUDY WITH DECENT RISK
OF FLURRIES OR VERY LIGHT SNOW AND NOT AS COLD WITH HIGHS INTO THE
20S AHEAD OF NEXT REINFORCING SHOT OF ARCTIC AIR. MINS 5 TO 15
ABOVE AS NEXT INVASION OF ARCTIC AIR ARRIVES TOWARD MORNING IN THE
NORTHWEST. WIND CHILLS FALLING TO 10 TO 20 BELOW ZERO BY TUESDAY
MORNING.
TUESDAY...CLEAR BLUSTERY AND COLD...SIMILAR TO SUNDAY WITH HIGHS 10
TO 20 ABOVE AND POSSIBLY A FEW DEGREES COLDER THAN THIS AND
NORTHWEST WINDS OF 20 TO 30 MPH AND LOW WIND CHILLS AT OR BELOW
ZERO. TUESDAY NIGHT...MINS ZERO TO 10 ABOVE AND POSSIBLY AT LEAST
3DEGREES COLDER FOR LATER SHIFTS WITH WIND CHILLS ONCE AGAIN TO FALL
TO NEAR 15 TO 20 BELOW NORTH OF I-80.
WEDNESDAY AND THURSDAY...DRY WITH A SLOW WARMING TREND WITH HIGHS
20S WEDNESDAY AND MOSTLY 30S ON THURSDAY. MINS MOSTLY 10 TO 20
ABOVE WEDNESDAY AM AND 20S THURSDAY AM.
FRIDAY...SEASONABLY COLD AND DRY WITH HIGHS NEAR NORMAL OR MID 20S
TO LOWER 30S AND MINS MOSTLY IN THE TEENS. NICHOLS
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 545 PM CST FRI JAN 8 2016
WEAK WINDS AND LOW LEVEL MOISTURE UNDER A SLOW MOVING LOW
PRESSURE SYSTEM WILL KEEP VLIFR TO LIFR CONDITIONS DUE TO DENSE
FOG AND DRIZZLE IN PLACE AT MLI...DBQ AND CID FOR MUCH OF THE
EVENING. IFR CONDITIONS WILL CONTINUE AT BRL. AS THE SYSTEM LIFTS
OUT...WINDS WILL VEER TO THE WEST AND THEN NORTHWEST AND INCREASE
LATE TONIGHT INTO SATURDAY MORNING. THIS WILL BRING IMPROVING
VISIBILITIES...GRADUALLY LIFTING CIGS...AND PRECIPITATION OF A
MORE SCATTERED NATURE IN THE FORM OF DRIZZLE AND RAIN...CHANGING
OVER TO LIGHT SNOW. SCATTERED SNOW SHOWERS WILL BE POSSIBLE
THROUGH SATURDAY WITH GUSTY NORTH TO NORTHWEST WINDS. CIGS AND
VISIBILITIES SHOULD IMPROVE TO IFR IF NOT MVFR THROUGH THE
DAY...BUT FORECAST CONFIDENCE IN THE RATE OF IMPROVEMENT IS LOW.
FOR NOW...WILL REMAIN BIASED TOWARD SLOWER IMPROVEMENT OR MORE
PESSIMISTIC CONDITIONS THROUGHOUT.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...SHEETS
SYNOPSIS...12
SHORT TERM...12
LONG TERM...NICHOLS
AVIATION...SHEETS
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1129 AM MST SAT JAN 9 2016
.UPDATE...
ISSUED AT 1129 AM MST SAT JAN 9 2016
UPDATE ISSUED TO REMOVE MENTION OF MORNING FLURRIES/SNOW SHOWERS
AND TO ADJUST CLOUD COVER BASED ON LATEST VISIBLE SATELLITE
TREND. CURRENTLY THE CWA IS SEEING TEMPS IN THE 20S WITH A
NORTHERLY FETCH UNDER MIXED SKY COVER. CLOUD DECK OVER PAST FEW
HOURS HAS THINNED IN SPOTS ALLOWING FOR MORE SUN TO REACH THE
AREA. DO EXPECT TREND TO CONTINUE THRU THE AFTERNOON HOURS SO
HAVE MENTIONED PARTLY TO MOSTLY SUNNY SKIES. WITH THIS ADDITIONAL
CLEARING...RADAR ECHOES HAVE BEEN TEMPERED...SO HAVE REMOVED
PRECIP. REST OF FORECAST ON TRACK.
&&
.SHORT TERM...(THIS MORNING THROUGH MONDAY NIGHT)
ISSUED AT 223 AM MST SAT JAN 9 2016
EARLY MORNING WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOWS A
LONGWAVE TROUGH ACROSS THE CENTRAL US ACROSS THE GLD CWA WITH A
CLOSED CENTER ROTATING OVER WESTERN OK TO THE SOUTHEAST. AN
AMPLIFIED RIDGE IN IN PLACE ACROSS THE WESTERN US UPSTREAM. AT THE
SURFACE CANADIAN HIGH PRESSURE EXTENDS SOUTH ACROSS THE NORTHERN
PLAINS ACROSS OUR CWA.
THIS MORNING-THIS AFTERNOON...WEAK FORCING BENEATH LONGWAVE TROUGH
HAS COMBINED WITH A SATURATED LAYER FROM 925-700 MB AND STEEP LOW
LOW LEVEL LAPSE RATES TO SUPPORT POCKETS OF FLURRIES ACROSS THE
AREA. AS THE CLOSED UPPER LOW TO THE SOUTHEAST MOVES EAST AND
SHORTWAVE RIDGING BUILDS INTO THE ROCKIES MUCH DRIER/STABLE AIR
SHOULD LEAD TO THIS ACTIVITY DISSIPATING. THERE COULD STILL BE A FEW
FLURRIES POSSIBLE THROUGH MIDDAY...HOWEVER OVERALL TREND SHOULD BE
FOR THIS TO END DURING THE MORNING HOURS. CAA WILL CONTINUE THIS
MORNING THROUGH THE AFTERNOON...AND IN LOCATIONS WITH PERSISTENT
CLOUD COVER WE COULD SEE HIGHS STRUGGLE TO REACH 20F. THERE IS SOME
INDICATION THAT WE COULD SEE BREAKS IN CLOUD COVER THIS
AFTERNOON...WHICH MAY ALLOW TEMPS (MAINLY SOUTH OF I-70) TO REACH
30F.
TONIGHT-MONDAY NIGHT...AMPLIFIED NW FLOW WILL BE IN PLACE ACROSS THE
PLAINS WITH MAIN STORM TRACK SPLIT AROUND OUR CWA. THERE WILL BE A
SERIES OF CLIPPERS ROTATING THROUGH THE MEAN FLOW...HOWEVER ANY
IMPACT ON SENSIBLE WEATHER OVER OUR CWA SHOULD BE LIMITED TO
INCREASES IN HIGH CLOUD COVER THROUGH THESE PERIODS.
REGARDING TEMPERATURES...THERE WILL BE A SLIGHT MODERATION IN THE
AIR MASS TONIGHT...HOWEVER WITH CANADIAN HIGH PRESSURE STILL BE A
STRONG INFLUENCE ON OUR TEMPS. THE QUESTION IS CLOUD COVER AND TDS AS
WITH CLEARING SKIES AND TDS ON DRIER END OF GUIDANCE COULD SUPPORT
LOWS NEAR ZERO AT SOME LOCATIONS. GUIDANCE SHOWS HIGH CLOUD COVER
INCREASING LATE WHICH LOWERS CONFIDENCE IN IDEAL RADIATIONAL
CONDITIONS. WEAK LEE TROUGH DEVELOPS IN EASTERN COLORADO/WYOMING
WITH DOWNSLOPE FLOW SUPPORTING CONTINUED MODERATION OF THE AIR MASS
THROUGH MONDAY. UPSTREAM SNOW FIELD AND PERIODS OF CLOUD COVER (AND
WINDS DURING THE NIGHT PERIODS) ALL LOWER CONFIDENCE IN TEMPS
THROUGH THE PERIODS. I STUCK WITH SIMILAR TRENDS AS PREVIOUS
FORECAST WITH HIGHS RETURNING TO SEASONAL VALUES AROUND 42 BY
MONDAY...AND OVERNIGHT LOWS IN THE SINGLE DIGITS (WEST) TO THE
TEENS(EAST). A QUICK MOVING SHORTWAVE TROUGH AND PASSING COLD FRONT
COMPLICATES LOWS MONDAY NIGHT...THOUGH WITH CAA IN PLACE EVEN CLOUD
COVER MAY NOT KEEP LOWS FROM DROPPING INTO THE TEENS.
.LONG TERM...(TUESDAY THROUGH FRIDAY)
ISSUED AT 117 AM MST SAT JAN 9 2016
MODELS CONTINUE TO NOT DO VERY WELL IN THIS TIME PERIOD. A LOT OF
SPREAD REMAINS NOT ONLY WITH THE DETERMINISTIC OUTPUT BUT ALSO THE
ENSEMBLES. MODELS DISAGREE ON HOW AMPLIFIED OR NOT THE FLOW IS WITH
THE OUTPUT OUT OF PHASE BY THE END OF THE PERIOD. ESSENTIALLY THE
FLOW REMAINS WEST TO NORTHWEST AND SOMETIMES EVEN MORE NORTH.
SO MOST OF THE WAVES GOING THROUGH LOOK TO BE OPEN AND FAST MOVING.
SO LITTLE TO NO CHANCE TO GET PRECIPITATION IN THIS SCENARIO. ONE OF
THOSE SHORTWAVES MOVES THROUGH IN THE THURSDAY TO FRIDAY TIME FRAME
AND BRINGS IN A MUCH COLDER AIR MASS. THE COMBINATION OF THE
SHORTWAVE AND COLD AIR ADVECTION SHOULD BE ABLE TO PRODUCE A SMALL
CHANCE OF LIGHT SNOW WHICH IS WHAT THE CRH_INIT GAVE ME FOR FRIDAY
WHICH IS REASONABLE.
WHAT LOOKS TO BE THE MOST UNCERTAIN IS THE TEMPERATURE FORECAST. IN
THIS FLOW COULD POSSIBLY GET A COLD SURGE/BACK DOOR COLD FRONT
MOVING INTO THE AREA. THE INIT GAVE ME WARMER TEMPERATURES IN THE
MIDDLE TO UPPER 40S ON WEDNESDAY AND THURSDAY...WHICH I WILL LEAVE
ALONE FOR NOW DUE TO MODEL DISAGREEMENT...BUT THERE IS DEFINITE
POTENTIAL FOR COLDER TEMPERATURES THOSE DAYS...DEPENDING OF COURSE
ON WHICH MODELS MID/UPPER SOLUTION WORKS OUT.
FRIDAY DEFINITELY LOOKS COLDER AND EVEN INTO THE REMAINDER OF NEXT
WEEKEND. THE PATTERN THE MODEL OUTPUT IS SHOWING...EVEN THOUGH
SHOWING DIFFERENCES...IS CONDUCIVE TO MUCH COLDER TEMPERATURES.
OVERALL NO CHANGES WILL BE MADE TO THE CRH_INIT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1028 AM MST SAT JAN 9 2016
FOR KGLD...WILL SEE A MVFR/VFR MIX IN CEILINGS THRU 20Z THEN VFR
CONDITIONS. BY 07Z SUNDAY...MVFR AGAIN THRU 12Z AS FOG TO 3SM AND
CEILINGS DROP TO OVC010. BY 12Z SUNDAY VFR PREVAILS. WINDS NORTH
AROUND 10KTS THRU 00Z SUNDAY...THEN LGT/VAR THRU 12Z BECOMING SW
AROUND 10KTS.
FOR KMCK...WILL SEE VFR CONDITIONS WITH CEILINGS RANGING
BKN035-150. BY 06Z SUNDAY...MVFR CONDITIONS IN 3SM FOR FOG AND
CEILINGS OVC010. BY 13Z VFR SKY CONDITIONS. WINDS NNE AROUND 10KTS
BECM LGT/VAR BY 00Z SUNDAY. BY 13Z SUNDAY...SW AROUND 10KTS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...JN
SHORT TERM...DR
LONG TERM...BULLER
AVIATION...JN
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1028 AM MST SAT JAN 9 2016
.UPDATE...
ISSUED AT 510 AM MST SAT JAN 9 2016
UPDATED TO ADD SLIGHT CHANCE POPS TO EASTERN CWA AND PATCHY FOG
TO EASTERN COLORADO. STRONGER RADAR RETURNS ARE EVIDENT AS BAND OF
SNOW DEVELOPED NEAR DEFORMATION ZONE ON NW SIDE OF UPPER LOW
CENTER. PROGRESSION OF UPPER LOW WILL CONTINUE TO BE TOWARDS THE
SOUTHEAST...HOWEVER THERE COULD BE STILL BE SEVERAL HOURS OF LIGHT
MEASURABLE SNOW (DUSTING) IN OUR EASTERN COUNTIES. OTHERWISE
FLURRIES/NON MEASURABLE SHOULD BE EXPECTED ACROSS REST OF CWA.
SHORT RANGE GUIDANCE STILL INDICATING POSSIBILITY FOR VIS TO DROP
TO ONE MILE OR LESS IN OUR FAR SOUTHEAST DUE TO FOG...THOUGH SO
FAR VIS HAS BEEN 3-6SM. ADDED PATCHY FOG MENTION IN COLORADO
COUNTIES TO ACCOUNT FOR POSSIBILITY.
&&
.SHORT TERM...(THIS MORNING THROUGH MONDAY NIGHT)
ISSUED AT 223 AM MST SAT JAN 9 2016
EARLY MORNING WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOWS A
LONGWAVE TROUGH ACROSS THE CENTRAL US ACROSS THE GLD CWA WITH A
CLOSED CENTER ROTATING OVER WESTERN OK TO THE SOUTHEAST. AN
AMPLIFIED RIDGE IN IN PLACE ACROSS THE WESTERN US UPSTREAM. AT THE
SURFACE CANADIAN HIGH PRESSURE EXTENDS SOUTH ACROSS THE NORTHERN
PLAINS ACROSS OUR CWA.
THIS MORNING-THIS AFTERNOON...WEAK FORCING BENEATH LONGWAVE TROUGH
HAS COMBINED WITH A SATURATED LAYER FROM 925-700 MB AND STEEP LOW
LOW LEVEL LAPSE RATES TO SUPPORT POCKETS OF FLURRIES ACROSS THE
AREA. AS THE CLOSED UPPER LOW TO THE SOUTHEAST MOVES EAST AND
SHORTWAVE RIDGING BUILDS INTO THE ROCKIES MUCH DRIER/STABLE AIR
SHOULD LEAD TO THIS ACTIVITY DISSIPATING. THERE COULD STILL BE A FEW
FLURRIES POSSIBLE THROUGH MIDDAY...HOWEVER OVERALL TREND SHOULD BE
FOR THIS TO END DURING THE MORNING HOURS. CAA WILL CONTINUE THIS
MORNING THROUGH THE AFTERNOON...AND IN LOCATIONS WITH PERSISTENT
CLOUD COVER WE COULD SEE HIGHS STRUGGLE TO REACH 20F. THERE IS SOME
INDICATION THAT WE COULD SEE BREAKS IN CLOUD COVER THIS
AFTERNOON...WHICH MAY ALLOW TEMPS (MAINLY SOUTH OF I-70) TO REACH
30F.
TONIGHT-MONDAY NIGHT...AMPLIFIED NW FLOW WILL BE IN PLACE ACROSS THE
PLAINS WITH MAIN STORM TRACK SPLIT AROUND OUR CWA. THERE WILL BE A
SERIES OF CLIPPERS ROTATING THROUGH THE MEAN FLOW...HOWEVER ANY
IMPACT ON SENSIBLE WEATHER OVER OUR CWA SHOULD BE LIMITED TO
INCREASES IN HIGH CLOUD COVER THROUGH THESE PERIODS.
REGARDING TEMPERATURES...THERE WILL BE A SLIGHT MODERATION IN THE
AIR MASS TONIGHT...HOWEVER WITH CANADIAN HIGH PRESSURE STILL BE A
STRONG INFLUENCE ON OUR TEMPS. THE QUESTION IS CLOUD COVER AND TDS AS
WITH CLEARING SKIES AND TDS ON DRIER END OF GUIDANCE COULD SUPPORT
LOWS NEAR ZERO AT SOME LOCATIONS. GUIDANCE SHOWS HIGH CLOUD COVER
INCREASING LATE WHICH LOWERS CONFIDENCE IN IDEAL RADIATIONAL
CONDITIONS. WEAK LEE TROUGH DEVELOPS IN EASTERN COLORADO/WYOMING
WITH DOWNSLOPE FLOW SUPPORTING CONTINUED MODERATION OF THE AIR MASS
THROUGH MONDAY. UPSTREAM SNOW FIELD AND PERIODS OF CLOUD COVER (AND
WINDS DURING THE NIGHT PERIODS) ALL LOWER CONFIDENCE IN TEMPS
THROUGH THE PERIODS. I STUCK WITH SIMILAR TRENDS AS PREVIOUS
FORECAST WITH HIGHS RETURNING TO SEASONAL VALUES AROUND 42 BY
MONDAY...AND OVERNIGHT LOWS IN THE SINGLE DIGITS (WEST) TO THE
TEENS(EAST). A QUICK MOVING SHORTWAVE TROUGH AND PASSING COLD FRONT
COMPLICATES LOWS MONDAY NIGHT...THOUGH WITH CAA IN PLACE EVEN CLOUD
COVER MAY NOT KEEP LOWS FROM DROPPING INTO THE TEENS.
.LONG TERM...(TUESDAY THROUGH FRIDAY)
ISSUED AT 117 AM MST SAT JAN 9 2016
MODELS CONTINUE TO NOT DO VERY WELL IN THIS TIME PERIOD. A LOT OF
SPREAD REMAINS NOT ONLY WITH THE DETERMINISTIC OUTPUT BUT ALSO THE
ENSEMBLES. MODELS DISAGREE ON HOW AMPLIFIED OR NOT THE FLOW IS WITH
THE OUTPUT OUT OF PHASE BY THE END OF THE PERIOD. ESSENTIALLY THE
FLOW REMAINS WEST TO NORTHWEST AND SOMETIMES EVEN MORE NORTH.
SO MOST OF THE WAVES GOING THROUGH LOOK TO BE OPEN AND FAST MOVING.
SO LITTLE TO NO CHANCE TO GET PRECIPITATION IN THIS SCENARIO. ONE OF
THOSE SHORTWAVES MOVES THROUGH IN THE THURSDAY TO FRIDAY TIME FRAME
AND BRINGS IN A MUCH COLDER AIR MASS. THE COMBINATION OF THE
SHORTWAVE AND COLD AIR ADVECTION SHOULD BE ABLE TO PRODUCE A SMALL
CHANCE OF LIGHT SNOW WHICH IS WHAT THE CRH_INIT GAVE ME FOR FRIDAY
WHICH IS REASONABLE.
WHAT LOOKS TO BE THE MOST UNCERTAIN IS THE TEMPERATURE FORECAST. IN
THIS FLOW COULD POSSIBLY GET A COLD SURGE/BACK DOOR COLD FRONT
MOVING INTO THE AREA. THE INIT GAVE ME WARMER TEMPERATURES IN THE
MIDDLE TO UPPER 40S ON WEDNESDAY AND THURSDAY...WHICH I WILL LEAVE
ALONE FOR NOW DUE TO MODEL DISAGREEMENT...BUT THERE IS DEFINITE
POTENTIAL FOR COLDER TEMPERATURES THOSE DAYS...DEPENDING OF COURSE
ON WHICH MODELS MID/UPPER SOLUTION WORKS OUT.
FRIDAY DEFINITELY LOOKS COLDER AND EVEN INTO THE REMAINDER OF NEXT
WEEKEND. THE PATTERN THE MODEL OUTPUT IS SHOWING...EVEN THOUGH
SHOWING DIFFERENCES...IS CONDUCIVE TO MUCH COLDER TEMPERATURES.
OVERALL NO CHANGES WILL BE MADE TO THE CRH_INIT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1028 AM MST SAT JAN 9 2016
FOR KGLD...WILL SEE A MVFR/VFR MIX IN CEILINGS THRU 20Z THEN VFR
CONDITIONS. BY 07Z SUNDAY...MVFR AGAIN THRU 12Z AS FOG TO 3SM AND
CEILINGS DROP TO OVC010. BY 12Z SUNDAY VFR PREVAILS. WINDS NORTH
AROUND 10KTS THRU 00Z SUNDAY...THEN LGT/VAR THRU 12Z BECOMING SW
AROUND 10KTS.
FOR KMCK...WILL SEE VFR CONDITIONS WITH CEILINGS RANGING
BKN035-150. BY 06Z SUNDAY...MVFR CONDITIONS IN 3SM FOR FOG AND
CEILINGS OVC010. BY 13Z VFR SKY CONDITIONS. WINDS NNE AROUND 10KTS
BECM LGT/VAR BY 00Z SUNDAY. BY 13Z SUNDAY...SW AROUND 10KTS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...DR
SHORT TERM...DR
LONG TERM...BULLER
AVIATION...JN
AREA FORECAST DISCUSSION
NWS GOODLAND KS
515 AM MST SAT JAN 9 2016
.UPDATE...
ISSUED AT 510 AM MST SAT JAN 9 2016
UPDATED TO ADD SLIGHT CHANCE POPS TO EASTERN CWA AND PATCHY FOG
TO EASTERN COLORADO. STRONGER RADAR RETURNS ARE EVIDENT AS BAND OF
SNOW DEVELOPED NEAR DEFORMATION ZONE ON NW SIDE OF UPPER LOW
CENTER. PROGRESSION OF UPPER LOW WILL CONTINUE TO BE TOWARDS THE
SOUTHEAST...HOWEVER THERE COULD BE STILL BE SEVERAL HOURS OF LIGHT
MEASURABLE SNOW (DUSTING) IN OUR EASTERN COUNTIES. OTHERWISE
FLURRIES/NON MEASURABLE SHOULD BE EXPECTED ACROSS REST OF CWA.
SHORT RANGE GUIDANCE STILL INDICATING POSSIBILITY FOR VIS TO DROP
TO ONE MILE OR LESS IN OUR FAR SOUTHEAST DUE TO FOG...THOUGH SO
FAR VIS HAS BEEN 3-6SM. ADDED PATCHY FOG MENTION IN COLORADO
COUNTIES TO ACCOUNT FOR POSSIBILITY.
&&
.SHORT TERM...(THIS MORNING THROUGH MONDAY NIGHT)
ISSUED AT 223 AM MST SAT JAN 9 2016
EARLY MORNING WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOWS A
LONGWAVE TROUGH ACROSS THE CENTRAL US ACROSS THE GLD CWA WITH A
CLOSED CENTER ROTATING OVER WESTERN OK TO THE SOUTHEAST. AN
AMPLIFIED RIDGE IN IN PLACE ACROSS THE WESTERN US UPSTREAM. AT THE
SURFACE CANADIAN HIGH PRESSURE EXTENDS SOUTH ACROSS THE NORTHERN
PLAINS ACROSS OUR CWA.
THIS MORNING-THIS AFTERNOON...WEAK FORCING BENEATH LONGWAVE TROUGH
HAS COMBINED WITH A SATURATED LAYER FROM 925-700 MB AND STEEP LOW
LOW LEVEL LAPSE RATES TO SUPPORT POCKETS OF FLURRIES ACROSS THE
AREA. AS THE CLOSED UPPER LOW TO THE SOUTHEAST MOVES EAST AND
SHORTWAVE RIDGING BUILDS INTO THE ROCKIES MUCH DRIER/STABLE AIR
SHOULD LEAD TO THIS ACTIVITY DISSIPATING. THERE COULD STILL BE A FEW
FLURRIES POSSIBLE THROUGH MIDDAY...HOWEVER OVERALL TREND SHOULD BE
FOR THIS TO END DURING THE MORNING HOURS. CAA WILL CONTINUE THIS
MORNING THROUGH THE AFTERNOON...AND IN LOCATIONS WITH PERSISTENT
CLOUD COVER WE COULD SEE HIGHS STRUGGLE TO REACH 20F. THERE IS SOME
INDICATION THAT WE COULD SEE BREAKS IN CLOUD COVER THIS
AFTERNOON...WHICH MAY ALLOW TEMPS (MAINLY SOUTH OF I-70) TO REACH
30F.
TONIGHT-MONDAY NIGHT...AMPLIFIED NW FLOW WILL BE IN PLACE ACROSS THE
PLAINS WITH MAIN STORM TRACK SPLIT AROUND OUR CWA. THERE WILL BE A
SERIES OF CLIPPERS ROTATING THROUGH THE MEAN FLOW...HOWEVER ANY
IMPACT ON SENSIBLE WEATHER OVER OUR CWA SHOULD BE LIMITED TO
INCREASES IN HIGH CLOUD COVER THROUGH THESE PERIODS.
REGARDING TEMPERATURES...THERE WILL BE A SLIGHT MODERATION IN THE
AIR MASS TONIGHT...HOWEVER WITH CANADIAN HIGH PRESSURE STILL BE A
STRONG INFLUENCE ON OUR TEMPS. THE QUESTION IS CLOUD COVER AND TDS AS
WITH CLEARING SKIES AND TDS ON DRIER END OF GUIDANCE COULD SUPPORT
LOWS NEAR ZERO AT SOME LOCATIONS. GUIDANCE SHOWS HIGH CLOUD COVER
INCREASING LATE WHICH LOWERS CONFIDENCE IN IDEAL RADIATIONAL
CONDITIONS. WEAK LEE TROUGH DEVELOPS IN EASTERN COLORADO/WYOMING
WITH DOWNSLOPE FLOW SUPPORTING CONTINUED MODERATION OF THE AIR MASS
THROUGH MONDAY. UPSTREAM SNOW FIELD AND PERIODS OF CLOUD COVER (AND
WINDS DURING THE NIGHT PERIODS) ALL LOWER CONFIDENCE IN TEMPS
THROUGH THE PERIODS. I STUCK WITH SIMILAR TRENDS AS PREVIOUS
FORECAST WITH HIGHS RETURNING TO SEASONAL VALUES AROUND 42 BY
MONDAY...AND OVERNIGHT LOWS IN THE SINGLE DIGITS (WEST) TO THE
TEENS(EAST). A QUICK MOVING SHORTWAVE TROUGH AND PASSING COLD FRONT
COMPLICATES LOWS MONDAY NIGHT...THOUGH WITH CAA IN PLACE EVEN CLOUD
COVER MAY NOT KEEP LOWS FROM DROPPING INTO THE TEENS.
.LONG TERM...(TUESDAY THROUGH FRIDAY)
ISSUED AT 117 AM MST SAT JAN 9 2016
MODELS CONTINUE TO NOT DO VERY WELL IN THIS TIME PERIOD. A LOT OF
SPREAD REMAINS NOT ONLY WITH THE DETERMINISTIC OUTPUT BUT ALSO THE
ENSEMBLES. MODELS DISAGREE ON HOW AMPLIFIED OR NOT THE FLOW IS WITH
THE OUTPUT OUT OF PHASE BY THE END OF THE PERIOD. ESSENTIALLY THE
FLOW REMAINS WEST TO NORTHWEST AND SOMETIMES EVEN MORE NORTH.
SO MOST OF THE WAVES GOING THROUGH LOOK TO BE OPEN AND FAST MOVING.
SO LITTLE TO NO CHANCE TO GET PRECIPITATION IN THIS SCENARIO. ONE OF
THOSE SHORTWAVES MOVES THROUGH IN THE THURSDAY TO FRIDAY TIME FRAME
AND BRINGS IN A MUCH COLDER AIR MASS. THE COMBINATION OF THE
SHORTWAVE AND COLD AIR ADVECTION SHOULD BE ABLE TO PRODUCE A SMALL
CHANCE OF LIGHT SNOW WHICH IS WHAT THE CRH_INIT GAVE ME FOR FRIDAY
WHICH IS REASONABLE.
WHAT LOOKS TO BE THE MOST UNCERTAIN IS THE TEMPERATURE FORECAST. IN
THIS FLOW COULD POSSIBLY GET A COLD SURGE/BACK DOOR COLD FRONT
MOVING INTO THE AREA. THE INIT GAVE ME WARMER TEMPERATURES IN THE
MIDDLE TO UPPER 40S ON WEDNESDAY AND THURSDAY...WHICH I WILL LEAVE
ALONE FOR NOW DUE TO MODEL DISAGREEMENT...BUT THERE IS DEFINITE
POTENTIAL FOR COLDER TEMPERATURES THOSE DAYS...DEPENDING OF COURSE
ON WHICH MODELS MID/UPPER SOLUTION WORKS OUT.
FRIDAY DEFINITELY LOOKS COLDER AND EVEN INTO THE REMAINDER OF NEXT
WEEKEND. THE PATTERN THE MODEL OUTPUT IS SHOWING...EVEN THOUGH
SHOWING DIFFERENCES...IS CONDUCIVE TO MUCH COLDER TEMPERATURES.
OVERALL NO CHANGES WILL BE MADE TO THE CRH_INIT.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 414 AM MST SAT JAN 9 2016
POCKETS OF STRATUS (AROUND 1500 FT AGL)...FLURRIES...AND LIGHT
FOG (VIS 4-6SM) HAVE CONTINUED TO IMPACT PARTS OF EASTERN
COLORADO...NORTHWEST KANSAS...AND SOUTHWEST NEBRASKA AS INDICATED
BY AREA OBS/SATELLITE/RADAR. SHORT RANGE GUIDANCE SHOWS THIS
CONTINUING TO DISSIPATE AND RETREAT WESTWARD INTO EASTERN COLORADO.
IN THE EARLY PART OF THE TAF PERIOD I KEPT LOWER CONDITIONS AT
KGLD LINGERING INTO THE THE MID MORNING WITH QUICKER IMPROVEMENT
EXPECTED AT KMCK. THERE IS A CHANCE THESE CONDITIONS COULD LINGER
AT KGLD INTO THE EARLY AFTERNOON...BASED ON RAP RH VALUES. EVEN
IF CONDITIONS LINGER LONGER ALL GUIDANCE SUPPORTS VFR FROM THE
AFTERNOON THROUGH THE REMAINING TAF PERIOD. NW WINDS 10-12KT TODAY
SHOULD DECREASE AFTER 00Z WITH LIGHT AND VARIABLE WINDS DUE TO
HIGH PRESSURE SHIFTING SOUTH THROUGH THE REGION.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...DR
SHORT TERM...DR
LONG TERM...BULLER
AVIATION...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
414 AM MST SAT JAN 9 2016
.SHORT TERM...(THIS MORNING THROUGH MONDAY NIGHT)
ISSUED AT 223 AM MST SAT JAN 9 2016
EARLY MORNING WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOWS A
LONGWAVE TROUGH ACROSS THE CENTRAL US ACROSS THE GLD CWA WITH A
CLOSED CENTER ROTATING OVER WESTERN OK TO THE SOUTHEAST. AN
AMPLIFIED RIDGE IN IN PLACE ACROSS THE WESTERN US UPSTREAM. AT THE
SURFACE CANADIAN HIGH PRESSURE EXTENDS SOUTH ACROSS THE NORTHERN
PLAINS ACROSS OUR CWA.
THIS MORNING-THIS AFTERNOON...WEAK FORCING BENEATH LONGWAVE TROUGH
HAS COMBINED WITH A SATURATED LAYER FROM 925-700 MB AND STEEP LOW
LOW LEVEL LAPSE RATES TO SUPPORT POCKETS OF FLURRIES ACROSS THE
AREA. AS THE CLOSED UPPER LOW TO THE SOUTHEAST MOVES EAST AND
SHORTWAVE RIDGING BUILDS INTO THE ROCKIES MUCH DRIER/STABLE AIR
SHOULD LEAD TO THIS ACTIVITY DISSIPATING. THERE COULD STILL BE A FEW
FLURRIES POSSIBLE THROUGH MIDDAY...HOWEVER OVERALL TREND SHOULD BE
FOR THIS TO END DURING THE MORNING HOURS. CAA WILL CONTINUE THIS
MORNING THROUGH THE AFTERNOON...AND IN LOCATIONS WITH PERSISTENT
CLOUD COVER WE COULD SEE HIGHS STRUGGLE TO REACH 20F. THERE IS SOME
INDICATION THAT WE COULD SEE BREAKS IN CLOUD COVER THIS
AFTERNOON...WHICH MAY ALLOW TEMPS (MAINLY SOUTH OF I-70) TO REACH
30F.
TONIGHT-MONDAY NIGHT...AMPLIFIED NW FLOW WILL BE IN PLACE ACROSS THE
PLAINS WITH MAIN STORM TRACK SPLIT AROUND OUR CWA. THERE WILL BE A
SERIES OF CLIPPERS ROTATING THROUGH THE MEAN FLOW...HOWEVER ANY
IMPACT ON SENSIBLE WEATHER OVER OUR CWA SHOULD BE LIMITED TO
INCREASES IN HIGH CLOUD COVER THROUGH THESE PERIODS.
REGARDING TEMPERATURES...THERE WILL BE A SLIGHT MODERATION IN THE
AIR MASS TONIGHT...HOWEVER WITH CANADIAN HIGH PRESSURE STILL BE A
STRONG INFLUENCE ON OUR TEMPS. THE QUESTION IS CLOUD COVER AND TDS AS
WITH CLEARING SKIES AND TDS ON DRIER END OF GUIDANCE COULD SUPPORT
LOWS NEAR ZERO AT SOME LOCATIONS. GUIDANCE SHOWS HIGH CLOUD COVER
INCREASING LATE WHICH LOWERS CONFIDENCE IN IDEAL RADIATIONAL
CONDITIONS. WEAK LEE TROUGH DEVELOPS IN EASTERN COLORADO/WYOMING
WITH DOWNSLOPE FLOW SUPPORTING CONTINUED MODERATION OF THE AIR MASS
THROUGH MONDAY. UPSTREAM SNOW FIELD AND PERIODS OF CLOUD COVER (AND
WINDS DURING THE NIGHT PERIODS) ALL LOWER CONFIDENCE IN TEMPS
THROUGH THE PERIODS. I STUCK WITH SIMILAR TRENDS AS PREVIOUS
FORECAST WITH HIGHS RETURNING TO SEASONAL VALUES AROUND 42 BY
MONDAY...AND OVERNIGHT LOWS IN THE SINGLE DIGITS (WEST) TO THE
TEENS(EAST). A QUICK MOVING SHORTWAVE TROUGH AND PASSING COLD FRONT
COMPLICATES LOWS MONDAY NIGHT...THOUGH WITH CAA IN PLACE EVEN CLOUD
COVER MAY NOT KEEP LOWS FROM DROPPING INTO THE TEENS.
.LONG TERM...(TUESDAY THROUGH FRIDAY)
ISSUED AT 117 AM MST SAT JAN 9 2016
MODELS CONTINUE TO NOT DO VERY WELL IN THIS TIME PERIOD. A LOT OF
SPREAD REMAINS NOT ONLY WITH THE DETERMINISTIC OUTPUT BUT ALSO THE
ENSEMBLES. MODELS DISAGREE ON HOW AMPLIFIED OR NOT THE FLOW IS WITH
THE OUTPUT OUT OF PHASE BY THE END OF THE PERIOD. ESSENTIALLY THE
FLOW REMAINS WEST TO NORTHWEST AND SOMETIMES EVEN MORE NORTH.
SO MOST OF THE WAVES GOING THROUGH LOOK TO BE OPEN AND FAST MOVING.
SO LITTLE TO NO CHANCE TO GET PRECIPITATION IN THIS SCENARIO. ONE OF
THOSE SHORTWAVES MOVES THROUGH IN THE THURSDAY TO FRIDAY TIME FRAME
AND BRINGS IN A MUCH COLDER AIR MASS. THE COMBINATION OF THE
SHORTWAVE AND COLD AIR ADVECTION SHOULD BE ABLE TO PRODUCE A SMALL
CHANCE OF LIGHT SNOW WHICH IS WHAT THE CRH_INIT GAVE ME FOR FRIDAY
WHICH IS REASONABLE.
WHAT LOOKS TO BE THE MOST UNCERTAIN IS THE TEMPERATURE FORECAST. IN
THIS FLOW COULD POSSIBLY GET A COLD SURGE/BACK DOOR COLD FRONT
MOVING INTO THE AREA. THE INIT GAVE ME WARMER TEMPERATURES IN THE
MIDDLE TO UPPER 40S ON WEDNESDAY AND THURSDAY...WHICH I WILL LEAVE
ALONE FOR NOW DUE TO MODEL DISAGREEMENT...BUT THERE IS DEFINITE
POTENTIAL FOR COLDER TEMPERATURES THOSE DAYS...DEPENDING OF COURSE
ON WHICH MODELS MID/UPPER SOLUTION WORKS OUT.
FRIDAY DEFINITELY LOOKS COLDER AND EVEN INTO THE REMAINDER OF NEXT
WEEKEND. THE PATTERN THE MODEL OUTPUT IS SHOWING...EVEN THOUGH
SHOWING DIFFERENCES...IS CONDUCIVE TO MUCH COLDER TEMPERATURES.
OVERALL NO CHANGES WILL BE MADE TO THE CRH_INIT.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 414 AM MST SAT JAN 9 2016
POCKETS OF STRATUS (AROUND 1500 FT AGL)...FLURRIES...AND LIGHT
FOG (VIS 4-6SM) HAVE CONTINUED TO IMPACT PARTS OF EASTERN
COLORADO...NORTHWEST KANSAS...AND SOUTHWEST NEBRASKA AS INDICATED
BY AREA OBS/SATELLITE/RADAR. SHORT RANGE GUIDANCE SHOWS THIS
CONTINUING TO DISSIPATE AND RETREAT WESTWARD INTO EASTERN COLORADO.
IN THE EARLY PART OF THE TAF PERIOD I KEPT LOWER CONDITIONS AT
KGLD LINGERING INTO THE THE MID MORNING WITH QUICKER IMPROVEMENT
EXPECTED AT KMCK. THERE IS A CHANCE THESE CONDITIONS COULD LINGER
AT KGLD INTO THE EARLY AFTERNOON...BASED ON RAP RH VALUES. EVEN
IF CONDITIONS LINGER LONGER ALL GUIDANCE SUPPORTS VFR FROM THE
AFTERNOON THROUGH THE REMAINING TAF PERIOD. NW WINDS 10-12KT TODAY
SHOULD DECREASE AFTER 00Z WITH LIGHT AND VARIABLE WINDS DUE TO
HIGH PRESSURE SHIFTING SOUTH THROUGH THE REGION.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...BULLER
AVIATION...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
223 AM MST SAT JAN 9 2016
.SHORT TERM...(THIS MORNING THROUGH MONDAY NIGHT)
ISSUED AT 223 AM MST SAT JAN 9 2016
EARLY MORNING WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOWS A
LONGWAVE TROUGH ACROSS THE CENTRAL US ACROSS THE GLD CWA WITH A
CLOSED CENTER ROTATING OVER WESTERN OK TO THE SOUTHEAST. AN
AMPLIFIED RIDGE IN IN PLACE ACROSS THE WESTERN US UPSTREAM. AT THE
SURFACE CANADIAN HIGH PRESSURE EXTENDS SOUTH ACROSS THE NORTHERN
PLAINS ACROSS OUR CWA.
THIS MORNING-THIS AFTERNOON...WEAK FORCING BENEATH LONGWAVE TROUGH
HAS COMBINED WITH A SATURATED LAYER FROM 925-700 MB AND STEEP LOW
LOW LEVEL LAPSE RATES TO SUPPORT POCKETS OF FLURRIES ACROSS THE
AREA. AS THE CLOSED UPPER LOW TO THE SOUTHEAST MOVES EAST AND
SHORTWAVE RIDGING BUILDS INTO THE ROCKIES MUCH DRIER/STABLE AIR
SHOULD LEAD TO THIS ACTIVITY DISSIPATING. THERE COULD STILL BE A FEW
FLURRIES POSSIBLE THROUGH MIDDAY...HOWEVER OVERALL TREND SHOULD BE
FOR THIS TO END DURING THE MORNING HOURS. CAA WILL CONTINUE THIS
MORNING THROUGH THE AFTERNOON...AND IN LOCATIONS WITH PERSISTENT
CLOUD COVER WE COULD SEE HIGHS STRUGGLE TO REACH 20F. THERE IS SOME
INDICATION THAT WE COULD SEE BREAKS IN CLOUD COVER THIS
AFTERNOON...WHICH MAY ALLOW TEMPS (MAINLY SOUTH OF I-70) TO REACH
30F.
TONIGHT-MONDAY NIGHT...AMPLIFIED NW FLOW WILL BE IN PLACE ACROSS THE
PLAINS WITH MAIN STORM TRACK SPLIT AROUND OUR CWA. THERE WILL BE A
SERIES OF CLIPPERS ROTATING THROUGH THE MEAN FLOW...HOWEVER ANY
IMPACT ON SENSIBLE WEATHER OVER OUR CWA SHOULD BE LIMITED TO
INCREASES IN HIGH CLOUD COVER THROUGH THESE PERIODS.
REGARDING TEMPERATURES...THERE WILL BE A SLIGHT MODERATION IN THE
AIR MASS TONIGHT...HOWEVER WITH CANADIAN HIGH PRESSURE STILL BE A
STRONG INFLUENCE ON OUR TEMPS. THE QUESTION IS CLOUD COVER AND TDS AS
WITH CLEARING SKIES AND TDS ON DRIER END OF GUIDANCE COULD SUPPORT
LOWS NEAR ZERO AT SOME LOCATIONS. GUIDANCE SHOWS HIGH CLOUD COVER
INCREASING LATE WHICH LOWERS CONFIDENCE IN IDEAL RADIATIONAL
CONDITIONS. WEAK LEE TROUGH DEVELOPS IN EASTERN COLORADO/WYOMING
WITH DOWNSLOPE FLOW SUPPORTING CONTINUED MODERATION OF THE AIR MASS
THROUGH MONDAY. UPSTREAM SNOW FIELD AND PERIODS OF CLOUD COVER (AND
WINDS DURING THE NIGHT PERIODS) ALL LOWER CONFIDENCE IN TEMPS
THROUGH THE PERIODS. I STUCK WITH SIMILAR TRENDS AS PREVIOUS
FORECAST WITH HIGHS RETURNING TO SEASONAL VALUES AROUND 42 BY
MONDAY...AND OVERNIGHT LOWS IN THE SINGLE DIGITS (WEST) TO THE
TEENS(EAST). A QUICK MOVING SHORTWAVE TROUGH AND PASSING COLD FRONT
COMPLICATES LOWS MONDAY NIGHT...THOUGH WITH CAA IN PLACE EVEN CLOUD
COVER MAY NOT KEEP LOWS FROM DROPPING INTO THE TEENS.
.LONG TERM...(TUESDAY THROUGH FRIDAY)
ISSUED AT 117 AM MST SAT JAN 9 2016
MODELS CONTINUE TO NOT DO VERY WELL IN THIS TIME PERIOD. A LOT OF
SPREAD REMAINS NOT ONLY WITH THE DETERMINISTIC OUTPUT BUT ALSO THE
ENSEMBLES. MODELS DISAGREE ON HOW AMPLIFIED OR NOT THE FLOW IS WITH
THE OUTPUT OUT OF PHASE BY THE END OF THE PERIOD. ESSENTIALLY THE
FLOW REMAINS WEST TO NORTHWEST AND SOMETIMES EVEN MORE NORTH.
SO MOST OF THE WAVES GOING THROUGH LOOK TO BE OPEN AND FAST MOVING.
SO LITTLE TO NO CHANCE TO GET PRECIPITATION IN THIS SCENARIO. ONE OF
THOSE SHORTWAVES MOVES THROUGH IN THE THURSDAY TO FRIDAY TIME FRAME
AND BRINGS IN A MUCH COLDER AIR MASS. THE COMBINATION OF THE
SHORTWAVE AND COLD AIR ADVECTION SHOULD BE ABLE TO PRODUCE A SMALL
CHANCE OF LIGHT SNOW WHICH IS WHAT THE CRH_INIT GAVE ME FOR FRIDAY
WHICH IS REASONABLE.
WHAT LOOKS TO BE THE MOST UNCERTAIN IS THE TEMPERATURE FORECAST. IN
THIS FLOW COULD POSSIBLY GET A COLD SURGE/BACK DOOR COLD FRONT
MOVING INTO THE AREA. THE INIT GAVE ME WARMER TEMPERATURES IN THE
MIDDLE TO UPPER 40S ON WEDNESDAY AND THURSDAY...WHICH I WILL LEAVE
ALONE FOR NOW DUE TO MODEL DISAGREEMENT...BUT THERE IS DEFINITE
POTENTIAL FOR COLDER TEMPERATURES THOSE DAYS...DEPENDING OF COURSE
ON WHICH MODELS MID/UPPER SOLUTION WORKS OUT.
FRIDAY DEFINITELY LOOKS COLDER AND EVEN INTO THE REMAINDER OF NEXT
WEEKEND. THE PATTERN THE MODEL OUTPUT IS SHOWING...EVEN THOUGH
SHOWING DIFFERENCES...IS CONDUCIVE TO MUCH COLDER TEMPERATURES.
OVERALL NO CHANGES WILL BE MADE TO THE CRH_INIT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 915 PM MST FRI JAN 8 2016
KGLD...MVFR CIGS EXPECTED AT TAF ISSUANCE FOR AN HOUR OR SO BEFORE
VFR CONDITIONS RETURN FOR THE REST OF THE TAF PERIOD. WINDS
THROUGH THE PERIOD FROM THE NORTH AROUND 10KTS.
KMCK...VFR CONDITIONS EXPECTED THROUGH THE PERIOD WITH WINDS FROM
THE NORTH NEAR 10KTS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...BULLER
AVIATION...99
AREA FORECAST DISCUSSION
NWS NEW ORLEANS LA
653 AM CST SAT JAN 9 2016
...SOUNDING DISCUSSION...
BALLOON WAS RELEASED SHORTLY BEFORE THE RAIN BEGAN AT THE OFFICE.
THERE WAS QUITE A BIT OF DRY AIR FROM ABOUT 1000 TO 10000
FEET WITH A PRECIPITABLE WATER VALUE A LITTLE OVER AN INCH. A
TEMPERATURE INVERSION EXTENDED TO ABOUT 900 FEET. WITH THE
SURFACE BOUNDARY AROUND THE LOUISIANA COAST...STORMS ACROSS MUCH
OF THE AREA HAVE BEEN MOSTLY ELEVATED...ESPECIALLY NORTH OF THE
TIDAL LAKES. A FEW STRONGER STORMS WERE ABLE TO PRODUCE HAIL
EARLIER IN THE NIGHT AND THE CURRENT FREEZING LEVEL AT ABOUT 8200
FEET. THE WIND PROFILE IS FAIRLY IMPRESSIVE WITH A NICE VEERING
WIND PROFILE AND GOOD SPEED SHEAR WITH THE CORE OF THE JET OVER
THE NORTHERN GULF OF MEXICO. PEAK WINDS SAMPLED BY THE SONDE WERE
133 KNOTS AT 39700 FEET.
12Z BALLOON INFO: NO ISSUES WITH THE FLIGHT THAT LASTED 83 MINUTES
AND BURST NEAR VANCLEAVE AT A HEIGHT OF 19.2 MILES ABOVE THE
GROUND 66 MILES DOWNRANGE FROM THE OFFICE.
ANSORGE
&&
.PREV DISCUSSION... /ISSUED 430 AM CST SAT JAN 9 2016/
SHORT TERM.. WIDE SWATH OF SHOWERS AND SCATTERED THUNDERSTORMS ARE
MOVING ACROSS THE CWA THIS MORNING. INTENSITY OF STORMS HAS DROPPED
OFF CONSIDERABLY HAS CONVECTION HAS MOVED INTO THE FORECAST AREA.
THIS ISN/T MUCH OF A SURPRISE BASED ON THE LOCAL 00Z SOUNDING WHICH
SHOWS STRONG WARM NOSE WHICH IS SEVERELY LIMITING INSTABILITY. DOWN
ON THE COAST...SFC TEMPS ARE SIGNIFICANTLY WARMER IN THE 60S AND 70S
OFFSHORE. IN THOSE AREAS (SOUTH OF I-10) SHOULD STILL HAVE ELEVATED
THUNDERSTORMS WITH ISOLATED STORMS CAPABLE OF PRODUCING SMALL HAIL.
FOR THE OFFSHORE WATERS COULD HAVE SOME SFC BASED CELLS WHICH COULD
LEAD TO A FEW WATERSPOUTS. THE FURTHER EAST CONVECTION MOVES ACROSS
LAND THE MORE IN TRACKS INTO LESS CONDUCIVE CONDITIONS. THE HRRR HAS
PERFORMED EXTREMELY WELL AND FEEL CONFIDENT THE OUTPUT OVER THE NEXT
SEVERAL HOURS IS A PRETTY GOOD REPRESENTATION OF WHAT TO EXPECT.
THAT WOULD BE STRONG STORMS OFFSHORE MOVING EAST...SCATTERED STORMS
SOUTH OF NEW ORLEANS AND MOSTLY RAIN NORTH OF THERE AS IT ALL SHIFTS
ACROSS THE CWA. THE BACK EDGE OF THIS RAINFALL SHOULD EXIT THE MS
COAST BY AROUND NOON TO SLIGHTLY SOONER. WRAP AROUND MOISTURE
ASSOCIATED WITH THE UPPER LOW COULD SPARK OFF SOME LINGERING SHOWERS
THIS AFTERNOON BUT NOT EXPECTING TOO MUCH IN THE WAY OF COVERAGE OR
INTENSITIES.
THE REMAINDER OF THE WEEKEND LOOKS QUIET AS STRONG SURFACE RIDGE
BUILDS IN ON SUNDAY. WILL HAVE A 15 TO 20 DEGREE DROP IN HIGHS.
STRONG CAA OCCURRING TOMORROW NIGHT. THIS WILL LEAD TO POSSIBLY THE
COLDEST TEMPERATURES OF THIS WINTER SEASON. DROPPED LOWS BY A COUPLE
DEGREES IN SOME LOCATIONS...BASICALLY SPLITTING MAV/MET FCST LOWS.
TEMPS WOULD RANGE FROM MID 20S TO LOWER 30S.
LONG TERM... BROAD UPPER TROUGH WILL TRACK ACROSS THE EASTERN HALF
OF THE COUNTRY. THIS WILL KEEP COLD AIR MAKING IT ACTUALLY FEEL LIKE
WINTER DOWN ALONG THE GULF COAST THROUGH TUESDAY. HIGHS MONDAY MAY
NOT EVEN BREAK THE 40S FOR MANY LOCATIONS. CLEAR SKIES...LIGHT WINDS
WITH HIGH PRESSURE SITTING RIGHT OVER THE REGION. AFTER TUE MORNING
THE REGION STARTS TO MODERATE WITH THE NEXT SYSTEM NOT ANTICIPATED
TO IMPACT THE REGION TILL THE LATTER HALF OF THE WEEK
MEFFER
AVIATION... VISIBILITIES HAVE RISE CONSIDERABLY IN THE LAST FEW
HOURS AS WIDE SWATH OF RAIN PROGRESSES ACROSS THE AREA.
HOWEVER...LIFR/IFR CEILINGS PERSIST AND INTERMITTENT HEAVY RAINFALL.
THE BULK OF HEAVY RAIN IS RACING EAST AND SHOULD BE EAST OF ALL
TERMINALS BY NOON WITH LINGERING SHOWERS DURING THE AFTERNOON HOURS.
CLEAR SKIES NOT EXPECTED UNTIL BEYOND THE TAF PERIOD.
MARINE... LATEST SFC ANALYSIS SHOWS TROUGH TRACKING EAST ACROSS
LOUISIANA WITH LOW CENTER IN ARKANSAS. FRONTAL BOUNDARY EXPECTED TO
MOVE ACROSS THE COASTAL WATERS THIS AFTERNOON AND CONTINUE WELL
SOUTH ACROSS THE ENTIRE GULF OF MEXICO. LATEST OBSERVED WINDS
OFFSHORE HOVERING NEAR EXERCISE CAUTION. LIKELY TO GET WIND
ENHANCEMENT WITH AREA OF SHOWERS AND STORMS MOVING ACROSS AND
DEFINITELY COULD BE SOME WATERSPOUTS WITH STRONGER CELLS. IN
ADDITION...WINDS TO SHIFT FROM SOUTHEAST THIS MORNING TO A MORE
WESTERLY AND THEN NORTHWESTERLY DIRECTION BY THE AFTN HOURS. SMALL
CRAFT ADVISORY GOING OUT THIS FCST PACKAGE STARTING AT 21Z FOR ALL
COASTAL WATERS AND CONTINUING THRU 15Z SUNDAY. NEARSHORE AND TIDAL
LAKES WILL BE THE FIRST TO DROP DOWN AS PRESSURE GRADIENT WEAKENS
WITH SFC RIDGE CLOSE IN ON THE AREA. HIGH PRESSURE WILL THEN SETTLE
OVER THE AREA SUNDAY NIGHT AND MONDAY...WITH NORTHERLY WINDS FALLING
TO BETWEEN 10 AND 15 KNOTS. THESE WINDS WILL GRADUALLY TURN MORE
EASTERLY BY TUESDAY.
MEFFER
DECISION SUPPORT...
DSS CODE....BLUE.
DEPLOYED...NONE.
ACTIVATION...NONE.
ACTIVITIES...ONGOING FLOODING ON MISSISSIPPI RIVER
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 RISK SVR AND/OR DIRECT
TROPICAL THREATS; EVENTS OF NATIONAL SIGNIFICANCE
&&
.PRELIMINARY POINT TEMPS/POPS...
MCB 68 37 47 25 / 50 10 0 0
BTR 70 40 49 28 / 40 10 10 0
ASD 70 43 51 28 / 80 10 0 0
MSY 71 44 50 33 / 70 10 0 0
GPT 70 42 52 28 / 80 10 0 0
PQL 73 43 53 26 / 80 10 0 0
&&
.LIX WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
GM...SMALL CRAFT ADVISORY FROM 3 PM THIS AFTERNOON TO 9 AM CST SUNDAY
FOR GMZ530-532-534-536-538-550-552-555-557-570-572-575-577.
MS...NONE.
GM...SMALL CRAFT ADVISORY FROM 3 PM THIS AFTERNOON TO 9 AM CST SUNDAY
FOR GMZ532-534-536-538-550-552-555-557-570-572-575-577.
&&
$$
AREA FORECAST DISCUSSION
NWS NEW ORLEANS LA
430 AM CST SAT JAN 9 2016
.SHORT TERM.. WIDE SWATH OF SHOWERS AND SCATTERED THUNDERSTORMS ARE
MOVING ACROSS THE CWA THIS MORNING. INTENSITY OF STORMS HAS DROPPED
OFF CONSIDERABLY HAS CONVECTION HAS MOVED INTO THE FORECAST AREA.
THIS ISN/T MUCH OF A SURPRISE BASED ON THE LOCAL 00Z SOUNDING WHICH
SHOWS STRONG WARM NOSE WHICH IS SEVERELY LIMITING INSTABILITY. DOWN
ON THE COAST...SFC TEMPS ARE SIGNIFICANTLY WARMER IN THE 60S AND 70S
OFFSHORE. IN THOSE AREAS (SOUTH OF I-10) SHOULD STILL HAVE ELEVATED
THUNDERSTORMS WITH ISOLATED STORMS CAPABLE OF PRODUCING SMALL HAIL.
FOR THE OFFSHORE WATERS COULD HAVE SOME SFC BASED CELLS WHICH COULD
LEAD TO A FEW WATERSPOUTS. THE FURTHER EAST CONVECTION MOVES ACROSS
LAND THE MORE IN TRACKS INTO LESS CONDUCIVE CONDITIONS. THE HRRR HAS
PERFORMED EXTREMELY WELL AND FEEL CONFIDENT THE OUTPUT OVER THE NEXT
SEVERAL HOURS IS A PRETTY GOOD REPRESENTATION OF WHAT TO EXPECT.
THAT WOULD BE STRONG STORMS OFFSHORE MOVING EAST...SCATTERED STORMS
SOUTH OF NEW ORLEANS AND MOSTLY RAIN NORTH OF THERE AS IT ALL SHIFTS
ACROSS THE CWA. THE BACK EDGE OF THIS RAINFALL SHOULD EXIT THE MS
COAST BY AROUND NOON TO SLIGHTLY SOONER. WRAP AROUND MOISTURE
ASSOCIATED WITH THE UPPER LOW COULD SPARK OFF SOME LINGERING SHOWERS
THIS AFTERNOON BUT NOT EXPECTING TOO MUCH IN THE WAY OF COVERAGE OR
INTENSITIES.
THE REMAINDER OF THE WEEKEND LOOKS QUIET AS STRONG SURFACE RIDGE
BUILDS IN ON SUNDAY. WILL HAVE A 15 TO 20 DEGREE DROP IN HIGHS.
STRONG CAA OCCURRING TOMORROW NIGHT. THIS WILL LEAD TO POSSIBLY THE
COLDEST TEMPERATURES OF THIS WINTER SEASON. DROPPED LOWS BY A COUPLE
DEGREES IN SOME LOCATIONS...BASICALLY SPLITTING MAV/MET FCST LOWS.
TEMPS WOULD RANGE FROM MID 20S TO LOWER 30S.
.LONG TERM... BROAD UPPER TROUGH WILL TRACK ACROSS THE EASTERN HALF
OF THE COUNTRY. THIS WILL KEEP COLD AIR MAKING IT ACTUALLY FEEL LIKE
WINTER DOWN ALONG THE GULF COAST THROUGH TUESDAY. HIGHS MONDAY MAY
NOT EVEN BREAK THE 40S FOR MANY LOCATIONS. CLEAR SKIES...LIGHT WINDS
WITH HIGH PRESSURE SITTING RIGHT OVER THE REGION. AFTER TUE MORNING
THE REGION STARTS TO MODERATE WITH THE NEXT SYSTEM NOT ANTICIPATED
TO IMPACT THE REGION TILL THE LATTER HALF OF THE WEEK
MEFFER
&&
.AVIATION... VISIBILITIES HAVE RISE CONSIDERABLY IN THE LAST FEW
HOURS AS WIDE SWATH OF RAIN PROGRESSES ACROSS THE AREA.
HOWEVER...LIFR/IFR CEILINGS PERSIST AND INTERMITTENT HEAVY RAINFALL.
THE BULK OF HEAVY RAIN IS RACING EAST AND SHOULD BE EAST OF ALL
TERMINALS BY NOON WITH LINGERING SHOWERS DURING THE AFTERNOON HOURS.
CLEAR SKIES NOT EXPECTED UNTIL BEYOND THE TAF PERIOD.
&&
.MARINE... LATEST SFC ANALYSIS SHOWS TROUGH TRACKING EAST ACROSS
LOUISIANA WITH LOW CENTER IN ARKANSAS. FRONTAL BOUNDARY EXPECTED TO
MOVE ACROSS THE COASTAL WATERS THIS AFTERNOON AND CONTINUE WELL
SOUTH ACROSS THE ENTIRE GULF OF MEXICO. LATEST OBSERVED WINDS
OFFSHORE HOVERING NEAR EXERCISE CAUTION. LIKELY TO GET WIND
ENHANCEMENT WITH AREA OF SHOWERS AND STORMS MOVING ACROSS AND
DEFINITELY COULD BE SOME WATERSPOUTS WITH STRONGER CELLS. IN
ADDITION...WINDS TO SHIFT FROM SOUTHEAST THIS MORNING TO A MORE
WESTERLY AND THEN NORTHWESTERLY DIRECTION BY THE AFTN HOURS. SMALL
CRAFT ADVISORY GOING OUT THIS FCST PACKAGE STARTING AT 21Z FOR ALL
COASTAL WATERS AND CONTINUING THRU 15Z SUNDAY. NEARSHORE AND TIDAL
LAKES WILL BE THE FIRST TO DROP DOWN AS PRESSURE GRADIENT WEAKENS
WITH SFC RIDGE CLOSE IN ON THE AREA. HIGH PRESSURE WILL THEN SETTLE
OVER THE AREA SUNDAY NIGHT AND MONDAY...WITH NORTHERLY WINDS FALLING
TO BETWEEN 10 AND 15 KNOTS. THESE WINDS WILL GRADUALLY TURN MORE
EASTERLY BY TUESDAY.
MEFFER
&&
.DECISION SUPPORT...
DSS CODE....BLUE.
DEPLOYED...NONE.
ACTIVATION...NONE.
ACTIVITIES...ONGOING FLOODING OF PEARL AND MISSISSIPPI RIVERS
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 RISK SVR AND/OR DIRECT
TROPICAL THREATS; EVENTS OF NATIONAL SIGNIFICANCE
&&
.PRELIMINARY POINT TEMPS/POPS...
MCB 67 37 47 25 / 50 10 0 0
BTR 70 40 49 28 / 40 10 10 0
ASD 71 43 51 28 / 80 10 0 0
MSY 71 44 50 33 / 70 10 0 0
GPT 70 42 52 28 / 80 10 0 0
PQL 73 43 53 26 / 80 10 0 0
&&
.LIX WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
GM...SMALL CRAFT ADVISORY FROM 3 PM THIS AFTERNOON TO 9 AM CST SUNDAY
FOR GMZ530-532-534-536-538-550-552-555-557-570-572-575-577.
MS...NONE.
GM...SMALL CRAFT ADVISORY FROM 3 PM THIS AFTERNOON TO 9 AM CST SUNDAY
FOR GMZ532-534-536-538-550-552-555-557-570-572-575-577.
&&
$$
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
1146 PM CST FRI JAN 8 2016
.AVIATION...
THE BACK EDGE OF A LARGE AREA OF SHOWERS AND EMBEDDED TSTMS...HAS
SHIFTED EAST OF I-49...AND WILL CONTINUE TO AFFECT KMLU AND KELD
THRU AROUND 08-10Z. MOSTLY LOW MVFR TO OCNL IFR CIGS AND VRBL
VSBYS EXPECTED WITHIN THIS RAIN. ISOLD CONVECTION HAS BEGUN TO
REDEVELOP NEAR THE KTXK TERMINAL...AND AREAS OF FOG DEVELOPING
OVER PORTIONS OF NE TX. VSBYS RECENTLY FELL UNDER A MILE AT
KTYR...KLFK...AND NEARBY NACOGDOCHES. VSBYS WILL IMPROVE WITH THE
ONSET OF STG COLD FRONT MOVG INTO SE OK/NE TX BY AROUND
09/12Z...WITH A FEW SHOWERS POSSIBLY REDEVELOPING NEAR FRONT.
MOSTLY WNW WINDS INCREASING TO AT LEAST 15 KTS AREAWIDE DURG DAY
WITH PASSAGE OF COLD FRONT...AND NE TX MAY SEE GUSTS OVER 30 KTS.
A STUBBORN LOW LVL INVERSION WILL KEEP MOST CIGS IN MVFR CAT THRU
THE AFTN...AND POSSIBLY BEYOND 10/00Z...WITH NW WINDS ONLY
DECREASING TO 10 TO 15 KTS AFTER 10/00Z./VII/.
&&
.PREV DISCUSSION... /ISSUED 1124 PM CST FRI JAN 8 2016/
DISCUSSION...
A LATE ZONE UPDATE WAS JUST SENT FOR THE EXPIRATION OF SVR WATCH
#1 FOR DEEP E TX/SABINE PARISH LA. DRY SLOTTING IS EVIDENT ON THE
RADAR AND WATER VAPOR IMAGERY THIS EVENING WELL AHEAD OF THE
SHORTWAVE TROUGH ROTATING THROUGH FAR W TX. AS HAS BEEN THE CASE
FOR MUCH OF THIS EVENING...STILL CAN`T RULE OUT ISOLATED HAILERS
FROM THE STRONGER STORMS EMBEDDED IN THE CONVECTION OVER NCNTRL
LA/SCNTRL AR GIVEN THE STEEP LAPSE RATES ALOFT AND LOW WET BULB
ZERO HEIGHTS EVIDENT ON THE 00Z KSHV/KFWD RAOBS...BUT THIS
CONVECTION IS BECOMING MORE REMOVED FROM THE BEST SOURCE OF
MUCAPE...WHICH REMAINS OVER S LA AND RANGES FROM 500-1000 J/KG.
THE ONGOING CONVECTION SHOULD QUICKLY DIMINISH FROM W TO E ACROSS
N LA/SCNTRL AR BETWEEN 06-09Z...ALTHOUGH THE 00Z NAM/GFS AND
LATEST HRRR RUNS DEPICT ADDITIONAL CONVECTION DEVELOPMENT LATE
TONIGHT OVER E TX...WHICH MAY BUILD NE INTO SW AR/EXTREME NW LA BY
DAYBREAK SATURDAY ALONG/JUST AHEAD OF A COLD FRONT AND ATTENDENT
TROUGH AXIS...WHICH REMAINS JUST NW OF THE REGION OVER ECNTRL
TX/SE OK/WRN AR.
HAVE LOWERED POPS TO MID CHANCE LATE TONIGHT FOR THESE
AREAS...WITH ISOLATED THUNDER STILL POSSIBLE GIVEN THE STEEP LAPSE
RATES ALOFT AHEAD OF THE TROUGH. HAVE KEPT LIKELY POPS OVER THE
ERN ZONES LATE FOR THE ONGOING CONVECTION...WITH THE TROUGH
EXPECTED TO OPEN UP AND LIFT NE INTO THE MID-SOUTH AND OH VALLEY
SATURDAY. ANY CONVECTION N OF I-20 SATURDAY MORNING SHOULD
DIMINISH BY AFTERNOON AS THIS SYSTEM PULLS AWAY FROM THE
REGION...AND COLDER AIR SPILLS SE IN WAKE OF THE FRONT. ONLY MADE
MINOR TWEAKS TO THE FORECAST MIN TEMPS...WITH TEMPS ONLY EXPECTED
TO FALL OFF A FEW MORE DEGREES AT BEST ACROSS MUCH OF THE
REGION...AS WE AWAIT THE ARRIVAL OF THE FRONT LATE.
PORTIONS OF NE TX/SE OK/SW AR MAY NEED A LAKE WIND ADVISORY FOR
THE STRONG POST-FRONTAL WINDS SATURDAY EVEN BENEATH THE STRATOCU
FIELD...BUT WILL DEFER THIS DECISION TO THE MID SHIFT.
ZONE UPDATE ALREADY OUT...GRIDS WILL BE AVAILABLE SHORTLY.
15
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 51 55 33 45 / 60 30 10 10
MLU 55 62 35 45 / 100 30 10 10
DEQ 47 50 26 42 / 50 40 10 10
TXK 49 52 29 42 / 40 40 10 10
ELD 51 57 30 44 / 100 50 10 10
TYR 45 50 30 44 / 40 20 10 10
GGG 49 52 30 44 / 40 20 10 10
LFK 52 56 32 48 / 20 20 10 10
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
LA...NONE.
OK...NONE.
TX...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
1124 PM CST FRI JAN 8 2016
.DISCUSSION...
A LATE ZONE UPDATE WAS JUST SENT FOR THE EXPIRATION OF SVR WATCH
#1 FOR DEEP E TX/SABINE PARISH LA. DRY SLOTTING IS EVIDENT ON THE
RADAR AND WATER VAPOR IMAGERY THIS EVENING WELL AHEAD OF THE
SHORTWAVE TROUGH ROTATING THROUGH FAR W TX. AS HAS BEEN THE CASE
FOR MUCH OF THIS EVENING...STILL CAN`T RULE OUT ISOLATED HAILERS
FROM THE STRONGER STORMS EMBEDDED IN THE CONVECTION OVER NCNTRL
LA/SCNTRL AR GIVEN THE STEEP LAPSE RATES ALOFT AND LOW WET BULB
ZERO HEIGHTS EVIDENT ON THE 00Z KSHV/KFWD RAOBS...BUT THIS
CONVECTION IS BECOMING MORE REMOVED FROM THE BEST SOURCE OF
MUCAPE...WHICH REMAINS OVER S LA AND RANGES FROM 500-1000 J/KG.
THE ONGOING CONVECTION SHOULD QUICKLY DIMINISH FROM W TO E ACROSS
N LA/SCNTRL AR BETWEEN 06-09Z...ALTHOUGH THE 00Z NAM/GFS AND
LATEST HRRR RUNS DEPICT ADDITIONAL CONVECTION DEVELOPMENT LATE
TONIGHT OVER E TX...WHICH MAY BUILD NE INTO SW AR/EXTREME NW LA BY
DAYBREAK SATURDAY ALONG/JUST AHEAD OF A COLD FRONT AND ATTENDENT
TROUGH AXIS...WHICH REMAINS JUST NW OF THE REGION OVER ECNTRL
TX/SE OK/WRN AR.
HAVE LOWERED POPS TO MID CHANCE LATE TONIGHT FOR THESE
AREAS...WITH ISOLATED THUNDER STILL POSSIBLE GIVEN THE STEEP LAPSE
RATES ALOFT AHEAD OF THE TROUGH. HAVE KEPT LIKELY POPS OVER THE
ERN ZONES LATE FOR THE ONGOING CONVECTION...WITH THE TROUGH
EXPECTED TO OPEN UP AND LIFT NE INTO THE MID-SOUTH AND OH VALLEY
SATURDAY. ANY CONVECTION N OF I-20 SATURDAY MORNING SHOULD
DIMINISH BY AFTERNOON AS THIS SYSTEM PULLS AWAY FROM THE
REGION...AND COLDER AIR SPILLS SE IN WAKE OF THE FRONT. ONLY MADE
MINOR TWEAKS TO THE FORECAST MIN TEMPS...WITH TEMPS ONLY EXPECTED
TO FALL OFF A FEW MORE DEGREES AT BEST ACROSS MUCH OF THE
REGION...AS WE AWAIT THE ARRIVAL OF THE FRONT LATE.
PORTIONS OF NE TX/SE OK/SW AR MAY NEED A LAKE WIND ADVISORY FOR
THE STRONG POST-FRONTAL WINDS SATURDAY EVEN BENEATH THE STRATOCU
FIELD...BUT WILL DEFER THIS DECISION TO THE MID SHIFT.
ZONE UPDATE ALREADY OUT...GRIDS WILL BE AVAILABLE SHORTLY.
15
&&
.PREV DISCUSSION... /ISSUED 626 PM CST FRI JAN 8 2016/
AVIATION...
DESPITE A LOW LVL INVERSION WHICH HAS TRAPPED IFR CIGS AND LOW
VSBYS ACROSS SOUTHERN PORTIONS OF THE AREA...MAINLY AT KLFK AND
KMLU...STEEP ELEVATED INSTABILITY ABOVE THE INVERSION IS ALLOWING
FOR SCATTERED TSTMS TO DEVELOP. THESE CONDITIONS...ALONG WITH
DRIER AIR IN MID LVLS AND LOW FRZG LVLS...IS ENHANCING HAIL
DEVELOPMENT IN THESE STORMS. CONVECTION MAY REMAIN MORE ISOLD
ACROSS NW PORTIONS OF AREA...INCLUDING KTYR...KGGG...AND KTXK.
CONVECTION MOVG NEWD AT 30 TO 40 KTS. MOSTLY LGT SOUTH WINDS AND
WETTING RAINS WILL ALSO ALLOW FOR CONTINUED LOW CIGS AND REDUCED
VSBYS AT REMAINING TERMINAL SITES OVERNIGHT. A STG COLD FRONT WILL
MOVE ACROSS AREA MID TO LATE MORNING ON SATURDAY. WINDS WILL SHIFT
TO THE SW-W...BEFORE SHIFTING AGAIN TO THE WNW THRU THE AFTN
HOURS. WINDS MAY INCREASE TO 15 TO 25 KTS OVER NE TX PORTION OF
THE AREA. LOW POSTFRONTAL STRATOCU MAY HOLD IN PLACES DURG THE
DAY...ALTHOUGH SOME SCATTERING OUT OF LOW CIGS IS POSSIBLE. /VII/
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 51 55 33 45 / 60 30 10 10
MLU 55 62 35 45 / 100 30 10 10
DEQ 47 50 26 42 / 50 40 10 10
TXK 49 52 29 42 / 40 40 10 10
ELD 51 57 30 44 / 100 50 10 10
TYR 45 50 30 44 / 40 20 10 10
GGG 49 52 30 44 / 40 20 10 10
LFK 52 56 32 48 / 20 20 10 10
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
LA...NONE.
OK...NONE.
TX...NONE.
&&
$$
15
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
320 PM EST SAT JAN 9 2016
.DISCUSSION...
PER RECENT WATER VAPOR IMAGERY...THE MAIN UPPER WAVE IS SHOWN
LIFTING INTO ARKANSAS WHILE A SHORTER WAVELENGTH IMPULSE IS NOW
LIFTING INTO CENTRAL ILLINOIS. MEANWHILE...THERE IS ONGOING
AMPLIFICATION IN THE BASE OF THE CENTRAL CANADIAN POLAR LOW INTO THE
UPPER MIDWEST. THIS HAS BEEN DRIVING AN ARCTIC BOUNDARY SOUTHWARD
ACROSS THE MID MS VALLEY. SFC LOW PRESSURE NOW LOCATED ALONG THE
AR/TN BORDER REGION WILL LIFT NORTHEAST INTO OHIO TONIGHT AS THE MID
LEVEL WAVE ROTATES INTO THE UPPER OHIO VALLEY. THIS WILL SLOW THE
EASTWARD PROGRESS OF THE ARCTIC FRONT ACROSS LOWER MI TONIGHT. DEEP
LAYER MOISTURE ADVECTION AND LARGER SCALE ASCENT ASSOCIATED WITH
THESE UPSTREAM SHORT WAVE FEATURES HAVE BEEN RESULTING IN A
NORTHWARD EXPANSION OF RAIN ACROSS INDIANA AND NE ILLINOIS THIS
AFTERNOON. ACROSS CENTRAL EAST CENTRAL IL AND DEEPER INTO THE COLD
AIR...THE PRECIP HAS BEEN IN THE FORM OF SNOW.
RECENT HI RES SOLUTIONS WITH SUPPORT OF UPSTREAM RADAR/SATELLITE
SUGGEST THE PRECIP WILL FIRST ARRIVE INTO SRN MI ALONG THE MID LEVEL
FRONT WHICH NOW EXTENDS FROM SRN MO INTO CNTL LOWER MI. THIS WILL
CAUSE RAIN TO OVERSPREAD THE WESTERN SECTIONS OF THE FCST AREA AND
SAGINAW VALLEY THIS EVENING. THE APPROACH OF THE UPPER WAVE TONIGHT
WILL CAUSE A TIGHTENING OF THE THERMAL GRADIENT ALONG THE FRONTAL
SLOPE...LEADING TO AN INTENSIFICATION IN THE MID LEVEL FRONTOGENESIS.
THIS ALONG WITH SOME DYNAMIC COOLING WILL LEAD TO A SHARP TRANSITION
ZONE BETWEEN RAIN AND HEAVY WET SNOW. THE RECENT HRRR WITH SUPPORT OF
UPSTREAM OBS CONTINUES TO SUGGEST THIS TRANSITION ZONE WILL BE OVER
MIDLAND/BAY COUNTIES LATE THIS EVENING. THE RAIN/SNOW LINE WILL THEN
SLOWLY PUSH SOUTHEAST ACROSS THE SAGINAW VALLEY OVERNIGHT. THE REST
OF THE FORECAST AREA WILL SEE LIGHT RAIN OR DRIZZLE DURING THIS TIME
PERIOD. THE 12Z MODEL SOLUTIONS ACTUALLY SUGGESTS THE BETTER MID
LEVEL DEFORMATION TRANSITIONING ACROSS THE REMAINDER OF THE FORECAST
AREA RATHER QUICKLY LATE TONIGHT INTO SUN MORNING AS THE UPPER WAVE
LIFTS ACROSS THE UPPER OHIO VALLEY. THE SURFACE LOW WILL IN TURN
DEEPEN AS IT LIFTS FROM NORTHERN OHIO INTO SRN ONTARIO SUN MORNING.
THIS WILL PROPEL THE ARCTIC FRONT ACROSS THE REST OF THE FORECAST
AREA...TRANSITIONING RAIN OVER TO SNOW. THE HEADLINES WILL REMAIN
UNCHANGED. THE POTENTIAL LONG DURATION /03Z TO 09Z/ OF MODERATE TO
HEAVY SNOW STILL SUGGESTS A GOOD CHANCE OF GETTING SNOW AMOUNTS OVER
6 INCHES ACROSS MIDLAND/NRN BAY. THE LATER CHANGE OVER ACROSS THE
ADVISORY AREA /SAGINAW/SHIAWASSEE/TUSCOLA/HURON SUGGESTS 1 TO 4 INCH
TYPE ACCUMS. THE REST OF THE FORECAST AREA WILL CHANGE OVER TO SNOW
AROUND THE TIME THAT THE LARGE SCALE FORCING IS WEAKENING...SO
AMOUNTS WILL BE MUCH LESS.
THE ARCTIC FRONT /FORECAST TO PUSH FROM THE SAGINAW VALLEY AND THUMB
AT 09Z ACROSS METRO DETROIT AND PORT HURON BY 12 TO 13Z/ WILL BE
MARKED AN INCREASE IN WIND GUSTS AND RAPID DROP IN TEMPS /INTO THE
MID 20S/. THIS COULD CAUSE SOME RAPID FREEZING OF WET/SNOW COVERED
ROADWAYS /ESPECIALLY IN THE ADVISORY AND WARNING COUNTIES/. THE
NEGATIVE TILT OF THE MID LEVEL SHORT WAVE LIFTING ACROSS THE UPPER
OHIO VALLEY SUN AND VERY STRONG BAROCLINICITY WILL LEAD TO A RAPIDLY
DEEPENING SURFACE LOW TRACKING ACROSS ONTARIO SUNDAY /FCST TO DROP
TO 982MB BY SUN EVENING/. THIS WILL INCREASE THE NORTHWEST GRADIENT
ACROSS SE MI. AS THE DEPTH OF THE COLD AIR INCREASES DURING SUN
AFTERNOON...WINDS WILL INCREASE /GUSTING UP TO 35 AND 40 MPH AT
TIMES/. TEMPS WILL ALSO CONTINUE TO DROP UNDER THE STEADY
INFILTRATION OF ARCTIC AIR...WITH WIND CHILLS DROPPING TOWARD ZERO
BY LATE SUN AFTERNOON.
MAIN FOCUS FOR THE REST OF THE FORECAST IS ON THE CLIPPER SYSTEM
THAT IS EXPECTED TO BRING ACCUMULATING SNOW TO THE AREA MONDAY NIGHT
AND TUESDAY. THE UPPER WAVE ASSOCIATED WITH THIS DISTURBANCE IS
EXPECTED TO RACE SOUTH-SOUTHEASTWARD ALONG THE WESTERN PERIPHERY OF
THE UPPER LOW OVER WESTERN HUDSON BAY...WITH THE SHEARED-OUT VORT
MAX QUICKLY BECOMING MORE CIRCULAR DIRECTLY OVER THE WESTERN GREAT
LAKES. THIS PROCESS IS EXPECTED TO LEAD TO RAPID CYCLOGENESIS OVER
MID-MICHIGAN/LAKE HURON MONDAY NIGHT INTO TUESDAY. NWP CONTINUES TO
BE IN GOOD AGREEMENT WITH THE EVOLUTION OF THESE FEATURES.
GFS/ECMWF/NAM ALL STRENGTHEN THE SURFACE LOW 8-12 MB IN 12 HR FROM
06-18Z TUESDAY.
THE FIRST PHASE OF THIS EVENT APPEARS TO BE A RELATIVELY UNIFORM
DISTRIBUTION OF LIGHT SNOW MONDAY NIGHT...FORCED BY ISENTROPIC LIFT
INITIALLY AND THEN WITH A CONTRIBUTION FROM DCVA AS THE UPPER WAVE
APPROACHES. THE PASSAGE OF A STRONG COLD FRONT AROUND 12Z TUESDAY
WILL LIKELY RESULT IN THE TRANSITION TO MORE OF A LAKE EFFECT EVENT.
A QUICK LOOK AT SOME OF THE LAKE EFFECT PARAMETERS SUGGESTS THE
POTENTIAL FOR SNOW SQUALLS EXTENDING INTO SOUTHEAST MICHIGAN. H850
TEMPS DROP TO NEAR -17C WITH 0-1KM THETA-E LAPSE RATES DOWN TO -6
K/KM OVER LAKE MICHIGAN. MEANWHILE TEMPS WILL BE DROPPING INTO THE
TEENS WITH SUSTAINED WINDS APPROACHING 20 MPH...WHICH MAY RESULT IN
WIND CHILLS INTO THE SINGLE DIGITS. ALL TOLD...EARLY INDICATIONS ARE
FOR 2 TO 4 INCHES WITH LOCALES THAT SEE MORE IN THE WAY OF LAKE
EFFECT TUESDAY TOWARD THE HIGHER END OF THAT RANGE.
TEMPERATURES WILL REMAIN ON THE CHILLY SIDE WITH PERHAPS A
MODERATING TREND TOWARD THE END OF THE WEEK AS THE HUDSON BAY UPPER
LOW DRIFTS A BIT NORTH AND EAST INTO QUEBEC. DISTURBANCES ROTATING
AROUND THE UPPER LOW WILL PROVIDE A FEW MORE CHANCES FOR LIGHT SNOW
FROM THE MIDDLE TO THE END OF NEXT WEEK.
&&
.MARINE...
MILD AIR AND LIGHT WINDS AROUND EARLY THIS EVENING WILL ABRUPTLY
CHANGE LATE TONIGHT AS A RAPIDLY DEEPENING LOW PRESSURE SYSTEM
TRACKS NORTHEAST THROUGH THE EASTERN GREAT LAKES. STRONG NORTHWEST
GALES WILL DEVELOP IN THE LOWS WAKE TOMORROW MORNING...AS ARCTIC AIR
SURGES INTO THE AREA. WITH THE GALES AND PLUMMETING TEMPERATURES...A
HEAVY FREEZING SPRAY WARNING IS IN EFFECT FOR SUNDAY AFTERNOON.
WINDS WILL DIMINISH AND BACK TO WESTERLY BY MONDAY MORNING BUT WILL
REMAIN ELEVATED IN THE 20 TO 30 KNOT RANGE. A SECOND SURGE OF ARCTIC
AIR IS EXPECTED ON TUESDAY...WHICH LOOKS TO SUPPORT ANOTHER PERIOD
OF STRONG NORTHWEST GALES AND HEAVY FREEZING SPRAY OVER THE OPEN
WATERS OF LAKE HURON. A GALE WATCH WAS NOT ISSUED DUE TO CURRENT
HEADLINE IN EFFECT.
&&
.HYDROLOGY...
DEEPENING LOW PRESSURE WILL TRACK THROUGH THE EASTERN GREAT LAKES
TONIGHT...SPREADING A GOOD SLUG OF MOISTURE INTO THE REGION.
PRECIPITATION WILL START OFF AS RAIN THIS EVENING BEFORE COLD AIR
SURGES IN FROM THE NORTH...QUICKLY CHANGING IT OVER TO SNOW BY
SUNDAY MORNING. HIGHEST SNOWFALL AMOUNTS WILL OCCUR ACROSS THE
SAGINAW VALLEY AREA...TAPERING OFF HEADING SOUTHWARD. TOTAL
PRECIPITATION AMOUNTS ARE EXPECTED TO RANGE FROM THREE QUARTERS OF
AN INCH ACROSS TRI-CITIES REGION TAPERING OFF SOUTHEAST TO A QUARTER
OF AN INCH IN AND AROUND DETROIT. TEMPERATURES PLUMMETING INTO THE
TEENS SUNDAY EVENING WILL FREEZE ANY LEFTOVER STANDING WATER.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...WINTER STORM WARNING FROM 9 PM THIS EVENING TO NOON EST SUNDAY FOR
MIZ047-048.
WINTER WEATHER ADVISORY FROM 3 AM TO 4 PM EST SUNDAY FOR MIZ049-054.
WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO NOON EST SUNDAY
FOR MIZ053-060.
LAKE HURON...HEAVY FREEZING SPRAY WARNING FROM 7 PM SUNDAY TO 4 AM EST MONDAY
FOR LHZ462>464.
GALE WARNING FROM 4 AM SUNDAY TO 6 AM EST MONDAY FOR LHZ361>363-
462>464.
GALE WARNING FROM 4 AM TO 11 PM EST SUNDAY FOR LHZ421-422-441>443.
HEAVY FREEZING SPRAY WARNING FROM 1 PM SUNDAY TO 4 AM EST MONDAY
FOR LHZ361>363.
LAKE ST CLAIR...GALE WARNING FROM 7 AM TO 11 PM EST SUNDAY FOR LCZ460.
MICHIGAN WATERS OF LAKE ERIE...GALE WARNING FROM 7 AM TO 11 PM EST SUNDAY FOR LEZ444.
&&
$$
DISCUSSION...SC/DT
MARINE.......SF
HYDROLOGY....SF
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
316 PM EST SAT JAN 9 2016
.DISCUSSION...
PER RECENT WATER VAPOR IMAGERY...THE MAIN UPPER WAVE IS SHOWN
LIFTING INTO ARKANSAS WHILE A SHORTER WAVELENGTH IMPULSE IS NOW
LIFTING INTO CENTRAL ILLINOIS. MEANWHILE...THERE IS ONGOING
AMPLIFICATION IN THE BASE OF THE CENTRAL CANADIAN POLAR LOW INTO THE
UPPER MIDWEST. THIS HAS BEEN DRIVING AN ARCTIC BOUNDARY SOUTHWARD
ACROSS THE MID MS VALLEY. SFC LOW PRESSURE NOW LOCATED ALONG THE
AR/TN BORDER REGION WILL LIFT NORTHEAST INTO OHIO TONIGHT AS THE MID
LEVEL WAVE ROTATES INTO THE UPPER OHIO VALLEY. THIS WILL SLOW THE
EASTWARD PROGRESS OF THE ARCTIC FRONT ACROSS LOWER MI TONIGHT. DEEP
LAYER MOISTURE ADVECTION AND LARGER SCALE ASCENT ASSOCIATED WITH
THESE UPSTREAM SHORT WAVE FEATURES HAVE BEEN RESULTING IN A
NORTHWARD EXPANSION OF RAIN ACROSS INDIANA AND NE ILLINOIS THIS
AFTERNOON. ACROSS CENTRAL EAST CENTRAL IL AND DEEPER INTO THE COLD
AIR...THE PRECIP HAS BEEN IN THE FORM OF SNOW.
RECENT HI RES SOLUTIONS WITH SUPPORT OF UPSTREAM RADAR/SATELLITE
SUGGEST THE PRECIP WILL FIRST ARRIVE INTO SRN MI ALONG THE MID LEVEL
FRONT WHICH NOW EXTENDS FROM SRN MO INTO CNTL LOWER MI. THIS WILL
CAUSE RAIN TO OVERSPREAD THE WESTERN SECTIONS OF THE FCST AREA AND
SAGINAW VALLEY THIS EVENING. THE APPROACH OF THE UPPER WAVE TONIGHT
WILL CAUSE A TIGHTENING OF THE THERMAL GRADIENT ALONG THE FRONTAL
SLOPE...LEADING TO AN INTENSIFICATION IN THE MID LEVEL FRONTOGENESIS.
THIS ALONG WITH SOME DYNAMIC COOLING WILL LEAD TO A SHARP TRANSITION
ZONE BETWEEN RAIN AND HEAVY WET SNOW. THE RECENT HRRR WITH SUPPORT OF
UPSTREAM OBS CONTINUES TO SUGGEST THIS TRANSITION ZONE WILL BE OVER
MIDLAND/BAY COUNTIES LATE THIS EVENING. THE RAIN/SNOW LINE WILL THEN
SLOWLY PUSH SOUTHEAST ACROSS THE SAGINAW VALLEY OVERNIGHT. THE REST
OF THE FORECAST AREA WILL SEE LIGHT RAIN OR DRIZZLE DURING THIS TIME
PERIOD. THE 12Z MODEL SOLUTIONS ACTUALLY SUGGESTS THE BETTER MID
LEVEL DEFORMATION TRANSITIONING ACROSS THE REMAINDER OF THE FORECAST
AREA RATHER QUICKLY LATE TONIGHT INTO SUN MORNING AS THE UPPER WAVE
LIFTS ACROSS THE UPPER OHIO VALLEY. THE SURFACE LOW WILL IN TURN
DEEPEN AS IT LIFTS FROM NORTHERN OHIO INTO SRN ONTARIO SUN MORNING.
THIS WILL PROPEL THE ARCTIC FRONT ACROSS THE REST OF THE FORECAST
AREA...TRANSITIONING RAIN OVER TO SNOW. THE HEADLINES WILL REMAIN
UNCHANGED. THE POTENTIAL LONG DURATION /03Z TO 09Z/ OF MODERATE TO
HEAVY SNOW STILL SUGGESTS A GOOD CHANCE OF GETTING SNOW AMOUNTS OVER
6 INCHES ACROSS MIDLAND/NRN BAY. THE LATER CHANGE OVER ACROSS THE
ADVISORY AREA /SAGINAW/SHIAWASSEE/TUSCOLA/HURON SUGGESTS 1 TO 4 INCH
TYPE ACCUMS. THE REST OF THE FORECAST AREA WILL CHANGE OVER TO SNOW
AROUND THE TIME THAT THE LARGE SCALE FORCING IS WEAKENING...SO
AMOUNTS WILL BE MUCH LESS.
THE ARCTIC FRONT /FORECAST TO PUSH FROM THE SAGINAW VALLEY AND THUMB
AT 09Z ACROSS METRO DETROIT AND PORT HURON BY 12 TO 13Z/ WILL BE
MARKED AN INCREASE IN WIND GUSTS AND RAPID DROP IN TEMPS /INTO THE
MID 20S/. THIS COULD CAUSE SOME RAPID FREEZING OF WET/SNOW COVERED
ROADWAYS /ESPECIALLY IN THE ADVISORY AND WARNING COUNTIES/. THE
NEGATIVE TILT OF THE MID LEVEL SHORT WAVE LIFTING ACROSS THE UPPER
OHIO VALLEY SUNDAY AND VERY STRONG BAROCLINICITY WILL LEAD TO A
RAPIDLY DEEPENING SURFACE LOW TRACKING ACROSS ONTARIO /FCST TO
DROP TO 982MB BY SUN EVENING/. THIS WILL INCREASE THE NORTHWEST
GRADIENT ACROSS SE MI. AS THE DEPTH OF THE COLD AIR INCREASES
DURING SUN AFTERNOON...WINDS WILL INCREASE /GUSTING UP TO 35 AND
40 MPH AT TIMES/. TEMPS WILL ALSO CONTINUE TO DROP UNDER THE
STEADY INFILTRATION OF ARCTIC AIR...WITH WIND CHILLS DROPPING
TOWARD ZERO BY LATE SUN AFTERNOON.
MAIN FOCUS FOR THE REST OF THE FORECAST IS ON THE CLIPPER SYSTEM
THAT IS EXPECTED TO BRING ACCUMULATING SNOW TO THE AREA MONDAY NIGHT
AND TUESDAY. THE UPPER WAVE ASSOCIATED WITH THIS DISTURBANCE IS
EXPECTED TO RACE SOUTH-SOUTHEASTWARD ALONG THE WESTERN PERIPHERY OF
THE UPPER LOW OVER WESTERN HUDSON BAY...WITH THE SHEARED-OUT VORT
MAX QUICKLY BECOMING MORE CIRCULAR DIRECTLY OVER THE WESTERN GREAT
LAKES. THIS PROCESS IS EXPECTED TO LEAD TO RAPID CYCLOGENESIS OVER
MID-MICHIGAN/LAKE HURON MONDAY NIGHT INTO TUESDAY. NWP CONTINUES TO
BE IN GOOD AGREEMENT WITH THE EVOLUTION OF THESE FEATURES.
GFS/ECMWF/NAM ALL STRENGTHEN THE SURFACE LOW 8-12 MB IN 12 HR FROM
06-18Z TUESDAY.
THE FIRST PHASE OF THIS EVENT APPEARS TO BE A RELATIVELY UNIFORM
DISTRIBUTION OF LIGHT SNOW MONDAY NIGHT...FORCED BY ISENTROPIC LIFT
INITIALLY AND THEN WITH A CONTRIBUTION FROM DCVA AS THE UPPER WAVE
APPROACHES. THE PASSAGE OF A STRONG COLD FRONT AROUND 12Z TUESDAY
WILL LIKELY RESULT IN THE TRANSITION TO MORE OF A LAKE EFFECT EVENT.
A QUICK LOOK AT SOME OF THE LAKE EFFECT PARAMETERS SUGGESTS THE
POTENTIAL FOR SNOW SQUALLS EXTENDING INTO SOUTHEAST MICHIGAN. H850
TEMPS DROP TO NEAR -17C WITH 0-1KM THETA-E LAPSE RATES DOWN TO -6
K/KM OVER LAKE MICHIGAN. MEANWHILE TEMPS WILL BE DROPPING INTO THE
TEENS WITH SUSTAINED WINDS APPROACHING 20 MPH...WHICH MAY RESULT IN
WIND CHILLS INTO THE SINGLE DIGITS. ALL TOLD...EARLY INDICATIONS ARE
FOR 2 TO 4 INCHES WITH LOCALES THAT SEE MORE IN THE WAY OF LAKE
EFFECT TUESDAY TOWARD THE HIGHER END OF THAT RANGE.
TEMPERATURES WILL REMAIN ON THE CHILLY SIDE WITH PERHAPS A
MODERATING TREND TOWARD THE END OF THE WEEK AS THE HUDSON BAY UPPER
LOW DRIFTS A BIT NORTH AND EAST INTO QUEBEC. DISTURBANCES ROTATING
AROUND THE UPPER LOW WILL PROVIDE A FEW MORE CHANCES FOR LIGHT SNOW
FROM THE MIDDLE TO THE END OF NEXT WEEK.
&&
.MARINE...
MILD AIR AND LIGHT WINDS AROUND EARLY THIS EVENING WILL ABRUPTLY
CHANGE LATE TONIGHT AS A RAPIDLY DEEPENING LOW PRESSURE SYSTEM
TRACKS NORTHEAST THROUGH THE EASTERN GREAT LAKES. STRONG NORTHWEST
GALES WILL DEVELOP IN THE LOWS WAKE TOMORROW MORNING...AS ARCTIC AIR
SURGES INTO THE AREA. WITH THE GALES AND PLUMMETING TEMPERATURES...A
HEAVY FREEZING SPRAY WARNING IS IN EFFECT FOR SUNDAY AFTERNOON.
WINDS WILL DIMINISH AND BACK TO WESTERLY BY MONDAY MORNING BUT WILL
REMAIN ELEVATED IN THE 20 TO 30 KNOT RANGE. A SECOND SURGE OF ARCTIC
AIR IS EXPECTED ON TUESDAY...WHICH LOOKS TO SUPPORT ANOTHER PERIOD
OF STRONG NORTHWEST GALES AND HEAVY FREEZING SPRAY OVER THE OPEN
WATERS OF LAKE HURON. A GALE WATCH WAS NOT ISSUED DUE TO CURRENT
HEADLINE IN EFFECT.
&&
.AVIATION...ISSUED 1200 PM EST SAT JAN 9 2016
HUNG UP FRONTAL BOUNDARY OVER SOUTHEAST MICHIGAN THIS AFTERNOON AND
EVENING WILL LEAD TO WEAK SURFACE WINDS AND PERSISTENT LOW LEVEL
MOISTURE TO SUSTAIN IFR/LIFR CONDITIONS...EXCEPT ACROSS SOUTHERN
TAF SITES THIS EARLY AFTERNOON WHERE PERIOD OF MVFR CEILINGS LOOK
TO PREVAIL. SURFACE DEW PTS OF 40+ F ACROSS MUCH OF SOUTHEAST
MICHIGAN INDICATIVE OF THE MILD AIR...AND LOOKS LIKE DEVELOPING
PRECIPITATION LATER TODAY WILL FALL AS RAIN OVER TAF SITES INTO
THIS EVENING...WITH ABRUPT AND SHARP CHANGEOVER TO SNOW OCCURRING
FROM NORTHWEST TO SOUTHEAST OVERNIGHT INTO EARLY SUNDAY MORNING.
AS THE CHANGEOVER TO SNOW OCCURS...NORTH-NORTHWEST WINDS WILL
RAMP UP QUICKLY...WITH GUSTS APPROACHING 35 KNOTS DURING THE DAY
ON SUNDAY AS RUSH OF ARCTIC AIR TAKES HOLD. AT THIS TIME...LOOKS
LIKE TOTAL SNOWFALL AMOUNTS WILL BE HIGHEST OVER MBS...BETWEEN 3
TO 5 INCHES...WITH FNT/PTK IN THE 1 TO 3 INCH RANGE...AND
DTW/YIP/DET CLOSER TO 1 INCH.
FOR DTW...MVFR CEILINGS/PARTIAL BREAKS IN THE CLOUD COVER AROUND
NOON HOUR SHOULD FILL BACK IN AND CEILINGS LOWERING BACK INTO IFR
BY EARLY EVENING. THIS EVENING AND TONIGHT NOT MUCH RAIN IS
EXPECTED...AS BULK OF PRECIPITATION FALLS TO THE WEST. CARRYING
IFR THROUGH EVENING AND BULK OF THE NIGHT...BUT LIFR REMAINS
POSSIBLE. HEAVIER PRECIPITATION SHOULD SPREAD IN 9-12Z...CHANGING
TO SNOW AROUND 12Z AS STRONG NORTHWEST WINDS PICK UP. SHORT WINDOW
FOR GOOD SNOWFALL RATES (VISIBILITY BELOW 1SM) SUGGESTS
ACCUMULATIONS AROUND 1 INCH...BUT LIGHT SNOW SHOWERS/FLURRIES
COULD PERSIST FOR MUCH OF THE DAY. HIGH CONFIDENCE IN WINDS
GUSTING BETWEEN 30 AND 35 KNOTS FROM 310-330 DIRECTION SUNDAY
MORNING/EARLY SUNDAY AFTERNOON.
//DTW THRESHOLD PROBABILITIES...
* HIGH FOR CEILINGS AOB 5000 FEET THROUGH THE TAF PERIOD.
* LOW FOR CIGS/VSBYS FALLING BELOW 200FT AND/OR 1/2SM THIS
EVENING THROUGH MID SUNDAY MORNING.
* HIGH FOR PRECIPITATION TYPE AS RAIN THROUGH 11Z SUNDAY
MORNING...BECOMING ALL SNOW BY 13Z.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...WINTER STORM WARNING FROM 9 PM THIS EVENING TO NOON EST SUNDAY FOR
MIZ047-048.
WINTER WEATHER ADVISORY FROM 3 AM TO 4 PM EST SUNDAY FOR MIZ049-054.
WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO NOON EST SUNDAY
FOR MIZ053-060.
LAKE HURON...HEAVY FREEZING SPRAY WARNING FROM 7 PM SUNDAY TO 4 AM EST MONDAY
FOR LHZ462>464.
GALE WARNING FROM 4 AM SUNDAY TO 6 AM EST MONDAY FOR LHZ361>363-
462>464.
GALE WARNING FROM 4 AM TO 11 PM EST SUNDAY FOR LHZ421-422-441>443.
HEAVY FREEZING SPRAY WARNING FROM 1 PM SUNDAY TO 4 AM EST MONDAY
FOR LHZ361>363.
LAKE ST CLAIR...GALE WARNING FROM 7 AM TO 11 PM EST SUNDAY FOR LCZ460.
MICHIGAN WATERS OF LAKE ERIE...GALE WARNING FROM 7 AM TO 11 PM EST SUNDAY FOR LEZ444.
&&
$$
DISCUSSION...SC/DT
MARINE.......SF
AVIATION.....SF
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
249 PM EST SAT JAN 9 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 407 AM EST SAT JAN 9 2016
MUCH COLDER AIR WILL BEGIN SURGING INTO THE AREA TODAY AND LEAD TO
BELOW NORMAL TEMPERATURES (WITH LAKE EFFECT SNOW) THROUGH AT LEAST
THE MIDDLE OF THE UPCOMING WORK WEEK. THE COLD AIR IS NOW STARTING
TO MOVE INTO THE WESTERN U.P. (RAP ANALYSIS SHOWING 850MB TEMPS
AROUND -7C AND -12C UPSTREAM IN THE MINNESOTA ARROWHEAD) AND THAT
WILL CONTINUE ACROSS THE AREA TODAY. BEFORE THAT OCCURS...A SURFACE
LOW IS CURRENTLY LOCATED OVER THE EASTERN U.P. AND IS CONTINUING TO
PRODUCE PRECIPITATION AS A SHORTWAVE LIFTS NORTHEAST THROUGH THE
AREA. WHILE MUCH OF THE PRECIPITATION OVER THE EASTERN U.P. FELL AS
RAIN THROUGH THE EVENING...HAVE BEEN SEEING A TRANSITION TO SNOW NOW
AS THE COLDER AIR IS STARTING TO WORK INTO THAT AREA (3AM METARS
SHOW KISQ IS THE ONLY SITE HANGING ON TO RAIN). EVENING SHIFT
FOLLOWED THE WETBULB0 HEIGHTS FROM THE RAP FOR THE RAIN/SNOW
TRANSITION AND THAT STILL SEEMS REASONABLE WITH THE LATEST RUNS.
HAVE FOLLOWED THAT WHICH TRANSITIONS THE LINGERING PRECIPITATION
OVER THE EAST TO SNOW BY THROUGH 5-6AM. OVER THE WEST HALF...HAVE
SEEN A LITTLE BIT OF A LULL (LIGHT SNOW FARTHER TO THE SOUTHWEST IN
SOUTHWESTERN WISCONSIN TIED WITH BETTER MOISTURE AND TRAILING COLD
FRONT)...BUT WITH THE COLDER AIR MOVING INTO THE AREA...VISIBILITIES
STARTED TO FALL WITH SNOW AT KIWD/KCMX AROUND 1AM AND HAVE BEEN
BOUNCING THROUGH THE NIGHT (LIKELY MORE TIED WITH THE LIGHT SNOW
SHOWERS MOVING IN FROM WISCONSIN THAN PURE LAKE EFFECT AT THIS
POINT). 3AM TEMPERATURES ARE STILL HOLDING ON TO THE LOWER 30S OVER
THE EASTERN 2/3RDS OF THE U.P. AND IN THE UPPER 20S TO THE WEST OF
THAT.
WITH THE COLDER AIR SURGING IN TODAY...EXPECT A TRANSITION TO PURE
LES THROUGH THE MORNING FOR THE NORTHERLY WIND SNOWBELTS BEFORE
GRADUALLY TRANSITIONING TO THE NORTHWEST WIND AREAS THROUGH THE
AFTERNOON. INVERSION HEIGHTS ARE FORECASTED TO BE AROUND 5KFT WHICH
IS SOMEWHAT LIMITING...BUT THE CLOUD WILL MOVE ENTIRELY WITHIN THE
DGZ THIS AFTERNOON AND WITH WINDS GENERALLY IN THE 15-25KT RANGE
THERE WON/T BE TOO MUCH FRACTURING. THUS...HAVE TRENDED SNOW RATIOS
UP INTO THE UPPER 20S AND WOULDN/T BE SURPRISED IF SOME LOCATIONS
END UP IN THE 30S TO 1 RANGE BASED OFF PAST SITUATIONS HERE AT OUR
OFFICE THAT HAVE YIELDED SNOW RATIOS AT OR EVEN ABOVE THOSE VALUES.
THE LOWER INVERSION HEIGHTS WILL LIKELY LIMIT THE OVERALL STRENGTH
OF THE LAKE EFFECT...BUT WITH RATIOS THAT HIGH STILL EXPECT
OCCASIONAL MODERATE SNOWFALL. HAVE SNOWFALL AMOUNTS OF 1 TO 4 INCHES
TODAY OVER THE FAVORED AREAS OVER THE FAR WESTERN U.P....WITH THE
GREATEST AMOUNTS OVER THE HIGHER TERRAIN OF GOGEBIC/ONTONAGON
COUNTIES. ONE OTHER LIMITING FACTOR FOR TODAY IS THAT THERE WILL BE
ENOUGH BACKING OF THE WINDS FROM NORTH-NORTHWEST TO NORTHWEST TODAY
TO MOVE THE BANDS AROUND ENOUGH TO LIMIT THE RESIDENCE TIME OF THE
STRONGER BANDS IN ANY ONE LOCATION. FARTHER TO THE EAST...EXPECT
SOME LAKE ENHANCEMENT NEAR LAKE SUPERIOR THROUGH THE DAY WITH THE
NORTH AND EVENTUALLY NORTHWEST WINDS...BUT INVERSION STRUGGLE TO
RISE MUCH ABOVE 4KFT WITH LESS FAVORABLE MOISTURE. THUS...DON/T
EXPECT MUCH MORE THAN A LIGHT DUSTING TO AN INCH OF SNOW TODAY THERE
AND EXPECT SCATTERED SNOW SHOWERS AND MAYBE A DUSTING OF SNOW FOR
THE REST OF THE U.P. AS THE COLD FRONT MOVES THROUGH AND THE SNOW
SHOWERS IN WISCONSIN SLIDE EAST-NORTHEAST THROUGH THE AREA. FINALLY
FOR TEMPERATURES...EXPECT STEADILY FALLING TEMPERATURES THROUGH THE
DAY...WITH VALUES AROUND SUNSET RANGING FROM THE MID TEENS OVER THE
WEST AND UPPER 20S OVER THE EAST.
FOR TONIGHT...EXPECT THE LAKE EFFECT TO CONTINUE FOR AREAS NEAR LAKE
SUPERIOR AS THE WINDS VEER BACK TO A MORE NORTHERLY DIRECTION IN
RESPONSE TO A SURFACE RIDGE TRYING TO NOSE INTO THE AREA AND A
SURFACE LOW LIFTING NORTH INTO THE LOWER GREAT LAKES. 850MB TEMPS
CONTINUE TO FALL THROUGH THE NIGHT (DOWN TO -21C OVER THE
WEST)...PUSHING THE CLOUD LAYER OUT OF THE DGZ. THAT WILL TRANSITION
THE SNOW FLAKE SIZE AND RATIOS DOWN THROUGH THE NIGHT. INVERSION
HEIGHTS STILL STAY IN THE 5-6KFT RANGE...SO STILL EXPECT LIGHT TO
OCCASIONALLY MODERATE LAKE EFFECT TO OCCUR AND HAVE ANOTHER 1-4
INCHES OF SNOW FOR THE SAME AREAS OUT WEST. THE EAST WILL SEE A
COMBINATION OF TWO FEATURES FOR TONIGHT. FIRST...THE AREA WILL BE
BRUSHED BY SNOW ASSOCIATED WITH THE SURFACE LOW LIFTING NORTHEAST
THROUGH THE EASTERN GREAT LAKES. THE HEAVIEST SNOW WILL OCCUR JUST
TO THE SOUTHEAST OF THE AREA...BUT COULD SEE A LIGHT DUSTING OVER
SOUTHERN SCHOOLCRAFT AND SOUTHERN LUCE COUNTIES. THEN FOR THE LAKE
EFFECT AREAS CLOSER TO LAKE SUPERIOR...THINK THINGS WILL INTENSIFY
THROUGH THE NIGHT AS THE COLDER AIR FINALLY ARRIVES...RAISING
INVERSION HEIGHTS TO 5-6KFT AND PUTS THE CLOUD WITHIN THE DGZ.
EXPECT SNOWFALL AMOUNTS TO BE SIMILAR TO OUT WEST IN THE FAVORED
TIME COINCIDING WITH THE CLOUD IN THE DGZ WITH 1 TO 3 INCHES OF
SNOW. WHILE WINDS WILL BE PICKING UP OVER THE EAST...THINK THE AREA
WILL NEED SOME TIME TO ACCUMULATE SNOW (AFTER THE RAIN THIS EVENING)
BEFORE THE BLOWING SNOW WILL REALLY PICKUP.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 249 PM EST SAT JAN 9 2016
NAM SHOWS A 500 MB RIDGE ON THE WEST COAST 00Z MON WITH A DEEP
TROUGH ACROSS THE UPPER GREAT LAKES. A SHORTWAVE DIGS DOWN THE
BACKSIDE OF THE TROUGH LATE ON MON AND MOVES THROUGH THE AREA MON
NIGHT. NAM SHOWS SOME 850-500 MB Q-VECTOR CONVERGENCE AND DEEPER
MOISTURE MOVING INTO THE AREA MON AFTERNOON LASTING INTO TUE
AFTERNOON. DID NOT MAKE TOO MANY CHANGES TO THE GOING FORECAST
OVERALL FOR TEMPERATURES OR POPS. LAKE EFFECT SNOW WILL CONTINUE IN
WEST AND NORTHWEST LAKE EFFECT SNOW BELTS.
IN THE EXTENDED...GFS AND ECMWF SHOW A 500 MB TROUGH OVER THE OVER
THE GREAT LAKES REGION INTO NEW ENGLAND 12Z WED WITH 850 MB
TEMPERATURES AROUND -21C OVER LAKE SUPERIOR. THE TROUGHING ALOFT
STAYS THROUGH 12Z THU WITH AN ALBERTA CLIPPER SYSTEM MOVING THROUGH
THE AREA. THE AIRMASS STARTS TO SLOWLY MODIFY ON FRI WITH THE TROUGH
AXIS TO THE EAST OF THE AREA 12Z FRI. THE AIRMASS CONTINUES TO
MODIFY SLOWLY ON SATURDAY. LAKE EFFECT SNOW WILL CONTINUE THROUGH
MOST OF THIS PERIOD ALONG WITH BELOW NORMAL TEMPERATURES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1254 PM EST SAT JAN 9 2016
LOOK FOR CONTINUED DETERIORATED CONDITIONS AT ALL SITES THROUGH THE
PERIOD...AS COLD AIR MOVING INTO THE AREA LEADS TO A PROLONGED
PERIOD OF LAKE EFFECT SNOW BEHIND A SERIES OF LOW PRESSURE SYSTEMS
TO OUR E AND HIGH PRESSURE SET UP ACROSS THE N AND CENTRAL PLAINS.
CEILINGS HAVE FALLEN TO MVFR TO HIGH END IFR /LOWEST AT IWD WHERE
THE FAVORABLE NW WINDS HAVE TAKEN HOLD. CONTINUED CALM WINDS REPORTED
AT IWD LOOK TO BE A CONTINUED TECHNICAL ISSUE FROM THE SITE. HAVE
EDITED THE LAST LINE OF THE TAF TO AMD LTD TO CLD AND VIS.
TEMPORARILY BLSN COULD BE A POSSIBILITY LATE TONIGHT THROUGH SUNDAY
MAINLY AT CMX AND SAW...WHERE THE PRESSURE GRADIENT REMAINS
STRONGEST.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 407 AM EST SAT JAN 9 2016
A BROAD SURFACE LOW OVER NORTHERN LAKE MICHIGAN WILL CONTINUE
NORTHEAST AND SLOWLY DISSIPATE TODAY WHILE A SECONDARY LOW TAKES
SHAPE IN THE SOUTHERN PLAINS. WINDS HAVE ALREADY SHIFTED TO THE
NORTHWEST OVER THE WESTERN HALF OF THE LAKE AND EXPECT THAT WIND
SHIFT TO SLIDE EAST ACROSS THE REST OF THE LAKE THROUGH THE MORNING
HOURS. AT THIS POINT...ONLY EXPECT WINDS UP TO 30KTS THROUGH THIS
EVENING...BUT AS THE SECONDARY LOW LIFTS NORTHEAST THROUGH THE
SOUTHEASTERN GREAT LAKES LATE TONIGHT AND SUNDAY MORNING...THE
GRADIENT BETWEEN THE LOW AND THE HIGH IN THE CENTRAL/NORTHERN
PLAINS WILL PRODUCE OCCASIONAL NORTHERLY GALES TO 35KTS OVER THE
EASTERN HALF OF LAKE SUPERIOR. WITH ONLY MARGINAL GALES
EXPECTED...WILL KEEP THE GALE WATCH IN PLACE AND ALLOW THE DAY
SHIFT ONE FINAL LOOK TO SEE IF THE MODELS CONTINUE TO TREND WINDS
DOWN. ALSO EXPECT A PERIOD OF FREEZING SPRAY AND MAY NEED A HEAVY
FREEZING SPRAY WARNING IF THE WINDS/WAVES STAY AT THE CURRENTLY
FORECASTED LEVELS. THE WINDS WILL QUICKLY DIMINISH SUNDAY NIGHT AS
THE LOW DEPARTS...BUT ANOTHER LOW WILL QUICKLY DROP SOUTHEAST ACROSS
THE UPPER GREAT LAKES MONDAY NIGHT AND BRING ANOTHER POTENTIAL FOR
NORTHERLY GALES TUESDAY INTO TUESDAY EVENING. BEHIND THE LOW...A
HIGH PRESSURE RIDGE WILL MOVE INTO THE AREA FOR WEDNESDAY AND
DIMINISH WINDS BELOW 25KTS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING FROM 7 AM TO 10 PM EST SUNDAY FOR LSZ249>251-266-
267.
LAKE MICHIGAN...
GALE WARNING FROM 7 AM TO 7 PM EST SUNDAY FOR LMZ221-248-250.
&&
$$
SHORT TERM...SRF
LONG TERM...07
AVIATION...KF
MARINE...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1255 PM EST SAT JAN 9 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 407 AM EST SAT JAN 9 2016
MUCH COLDER AIR WILL BEGIN SURGING INTO THE AREA TODAY AND LEAD TO
BELOW NORMAL TEMPERATURES (WITH LAKE EFFECT SNOW) THROUGH AT LEAST
THE MIDDLE OF THE UPCOMING WORK WEEK. THE COLD AIR IS NOW STARTING
TO MOVE INTO THE WESTERN U.P. (RAP ANALYSIS SHOWING 850MB TEMPS
AROUND -7C AND -12C UPSTREAM IN THE MINNESOTA ARROWHEAD) AND THAT
WILL CONTINUE ACROSS THE AREA TODAY. BEFORE THAT OCCURS...A SURFACE
LOW IS CURRENTLY LOCATED OVER THE EASTERN U.P. AND IS CONTINUING TO
PRODUCE PRECIPITATION AS A SHORTWAVE LIFTS NORTHEAST THROUGH THE
AREA. WHILE MUCH OF THE PRECIPITATION OVER THE EASTERN U.P. FELL AS
RAIN THROUGH THE EVENING...HAVE BEEN SEEING A TRANSITION TO SNOW NOW
AS THE COLDER AIR IS STARTING TO WORK INTO THAT AREA (3AM METARS
SHOW KISQ IS THE ONLY SITE HANGING ON TO RAIN). EVENING SHIFT
FOLLOWED THE WETBULB0 HEIGHTS FROM THE RAP FOR THE RAIN/SNOW
TRANSITION AND THAT STILL SEEMS REASONABLE WITH THE LATEST RUNS.
HAVE FOLLOWED THAT WHICH TRANSITIONS THE LINGERING PRECIPITATION
OVER THE EAST TO SNOW BY THROUGH 5-6AM. OVER THE WEST HALF...HAVE
SEEN A LITTLE BIT OF A LULL (LIGHT SNOW FARTHER TO THE SOUTHWEST IN
SOUTHWESTERN WISCONSIN TIED WITH BETTER MOISTURE AND TRAILING COLD
FRONT)...BUT WITH THE COLDER AIR MOVING INTO THE AREA...VISIBILITIES
STARTED TO FALL WITH SNOW AT KIWD/KCMX AROUND 1AM AND HAVE BEEN
BOUNCING THROUGH THE NIGHT (LIKELY MORE TIED WITH THE LIGHT SNOW
SHOWERS MOVING IN FROM WISCONSIN THAN PURE LAKE EFFECT AT THIS
POINT). 3AM TEMPERATURES ARE STILL HOLDING ON TO THE LOWER 30S OVER
THE EASTERN 2/3RDS OF THE U.P. AND IN THE UPPER 20S TO THE WEST OF
THAT.
WITH THE COLDER AIR SURGING IN TODAY...EXPECT A TRANSITION TO PURE
LES THROUGH THE MORNING FOR THE NORTHERLY WIND SNOWBELTS BEFORE
GRADUALLY TRANSITIONING TO THE NORTHWEST WIND AREAS THROUGH THE
AFTERNOON. INVERSION HEIGHTS ARE FORECASTED TO BE AROUND 5KFT WHICH
IS SOMEWHAT LIMITING...BUT THE CLOUD WILL MOVE ENTIRELY WITHIN THE
DGZ THIS AFTERNOON AND WITH WINDS GENERALLY IN THE 15-25KT RANGE
THERE WON/T BE TOO MUCH FRACTURING. THUS...HAVE TRENDED SNOW RATIOS
UP INTO THE UPPER 20S AND WOULDN/T BE SURPRISED IF SOME LOCATIONS
END UP IN THE 30S TO 1 RANGE BASED OFF PAST SITUATIONS HERE AT OUR
OFFICE THAT HAVE YIELDED SNOW RATIOS AT OR EVEN ABOVE THOSE VALUES.
THE LOWER INVERSION HEIGHTS WILL LIKELY LIMIT THE OVERALL STRENGTH
OF THE LAKE EFFECT...BUT WITH RATIOS THAT HIGH STILL EXPECT
OCCASIONAL MODERATE SNOWFALL. HAVE SNOWFALL AMOUNTS OF 1 TO 4 INCHES
TODAY OVER THE FAVORED AREAS OVER THE FAR WESTERN U.P....WITH THE
GREATEST AMOUNTS OVER THE HIGHER TERRAIN OF GOGEBIC/ONTONAGON
COUNTIES. ONE OTHER LIMITING FACTOR FOR TODAY IS THAT THERE WILL BE
ENOUGH BACKING OF THE WINDS FROM NORTH-NORTHWEST TO NORTHWEST TODAY
TO MOVE THE BANDS AROUND ENOUGH TO LIMIT THE RESIDENCE TIME OF THE
STRONGER BANDS IN ANY ONE LOCATION. FARTHER TO THE EAST...EXPECT
SOME LAKE ENHANCEMENT NEAR LAKE SUPERIOR THROUGH THE DAY WITH THE
NORTH AND EVENTUALLY NORTHWEST WINDS...BUT INVERSION STRUGGLE TO
RISE MUCH ABOVE 4KFT WITH LESS FAVORABLE MOISTURE. THUS...DON/T
EXPECT MUCH MORE THAN A LIGHT DUSTING TO AN INCH OF SNOW TODAY THERE
AND EXPECT SCATTERED SNOW SHOWERS AND MAYBE A DUSTING OF SNOW FOR
THE REST OF THE U.P. AS THE COLD FRONT MOVES THROUGH AND THE SNOW
SHOWERS IN WISCONSIN SLIDE EAST-NORTHEAST THROUGH THE AREA. FINALLY
FOR TEMPERATURES...EXPECT STEADILY FALLING TEMPERATURES THROUGH THE
DAY...WITH VALUES AROUND SUNSET RANGING FROM THE MID TEENS OVER THE
WEST AND UPPER 20S OVER THE EAST.
FOR TONIGHT...EXPECT THE LAKE EFFECT TO CONTINUE FOR AREAS NEAR LAKE
SUPERIOR AS THE WINDS VEER BACK TO A MORE NORTHERLY DIRECTION IN
RESPONSE TO A SURFACE RIDGE TRYING TO NOSE INTO THE AREA AND A
SURFACE LOW LIFTING NORTH INTO THE LOWER GREAT LAKES. 850MB TEMPS
CONTINUE TO FALL THROUGH THE NIGHT (DOWN TO -21C OVER THE
WEST)...PUSHING THE CLOUD LAYER OUT OF THE DGZ. THAT WILL TRANSITION
THE SNOW FLAKE SIZE AND RATIOS DOWN THROUGH THE NIGHT. INVERSION
HEIGHTS STILL STAY IN THE 5-6KFT RANGE...SO STILL EXPECT LIGHT TO
OCCASIONALLY MODERATE LAKE EFFECT TO OCCUR AND HAVE ANOTHER 1-4
INCHES OF SNOW FOR THE SAME AREAS OUT WEST. THE EAST WILL SEE A
COMBINATION OF TWO FEATURES FOR TONIGHT. FIRST...THE AREA WILL BE
BRUSHED BY SNOW ASSOCIATED WITH THE SURFACE LOW LIFTING NORTHEAST
THROUGH THE EASTERN GREAT LAKES. THE HEAVIEST SNOW WILL OCCUR JUST
TO THE SOUTHEAST OF THE AREA...BUT COULD SEE A LIGHT DUSTING OVER
SOUTHERN SCHOOLCRAFT AND SOUTHERN LUCE COUNTIES. THEN FOR THE LAKE
EFFECT AREAS CLOSER TO LAKE SUPERIOR...THINK THINGS WILL INTENSIFY
THROUGH THE NIGHT AS THE COLDER AIR FINALLY ARRIVES...RAISING
INVERSION HEIGHTS TO 5-6KFT AND PUTS THE CLOUD WITHIN THE DGZ.
EXPECT SNOWFALL AMOUNTS TO BE SIMILAR TO OUT WEST IN THE FAVORED
TIME COINCIDING WITH THE CLOUD IN THE DGZ WITH 1 TO 3 INCHES OF
SNOW. WHILE WINDS WILL BE PICKING UP OVER THE EAST...THINK THE AREA
WILL NEED SOME TIME TO ACCUMULATE SNOW (AFTER THE RAIN THIS EVENING)
BEFORE THE BLOWING SNOW WILL REALLY PICKUP.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 349 AM EST SAT JAN 9 2016
MEDIUM/EXTENDED RANGE GUIDANCE CONTINUES TO INDICATE A HI AMPLITUDE
WRN NAMERICA UPR RDG/ERN TROF WL DOMINATE THE COMING WEEK...
RESULTING IN BLO NORMAL TO WELL BLO NORMAL TEMPS FOR UPR MI MOST OF
THE TIME. LES WL BE COMMON DURING MUCH OF THIS TIME AS THE COLD
ARCTIC AIR FLOWS OVER THE RELATIVELY WARM WATERS OF LK SUP.
SUN...SINCE SHRTWV LIFTING NEWD FM THE LOWER MS RIVER VALLEY TOWARD
THE UPR OH RIVER VALLY AT 12Z SUN IS FCST TO REMAIN OUT OF PHASE
WITH ARCTIC BRANCH TROF SHIFTING INTO THE WRN GREAT LKS...ASSOCIATED
SFC LO AND BULK OF DYNAMIC SUPPORT ASSOCIATED WITH THE SHRTWV/
DEEPER MSTR/HEAVIER PCPN ARE FCST TO REMAIN MAINLY TO THE E OF THE
CWA. HOWEVER...AS CYC NNW SLOWLY BACK NW FLOW DRAWS H85 TEMPS IN THE
-20C TO -23C RANGE INTO THE UPR LKS...WL FCST CATEGORICAL POPS FOR
LES IN THE FAVORED SN BELTS NEAR LK SUP. BUT THE INTENSITY OF THIS
LES WL BE LIMITED BY RATHER LO INVRN BASE FCST NEAR H85 AND INCRSGLY
POOR SN GROWTH ASSOCIATED WITH THE ARRIVAL OF THE VERY COLD AIR THAT
WL PUSH THE DGZ TO NEAR THE SFC. DOWNSLOPE NATURE OF THE BACKING
LLVL NW FLOW WL BRING DRY WX TO THE SCENTRAL. WITH THE INFLUX OF THE
ARCTIC AIR...MAX TEMPS ON SUN WL HOLD IN THE SINGLE DIGITS ABOVE 0F
OVER MUCH OF THE W HALF.
SUN NGT/MON...NW LLVL WINDS AT 00Z MON ARE FCST TO BACK SLOWLY AS
THE DEEPENING SFC LO EXITS TO THE NE THRU QUEBEC AND COLD SFC HI
PRES IN THE PLAINS SHIFTS INTO THE LOWER MS RIVER VALLEY IN ADVANCE
OF ANOTHER SHRTWV WITHIN THE NW FLOW ALF DIGGING SEWD TOWARD THE UPR
MS RIVER VALLEY. H85 TEMPS ARE FCST TO MODERATE A FEW DEGREES TO
-18C TO -21C. ALTHOUGH THE INCRSG H85 TEMPS WL ALLOW FOR BETTER SN
GROWTH...THE SHIFTING WINDS SHOULD TEND TO LIMIT BAND RESIDENCE
TIME/PURE LES ACCUMS. HOWEVER...THERE MAY BE SOME MDT LES OVER NRN
ONTONAGON/CENTRAL HOUGHTON COUNTY WHERE MORE PERSISTENT LLVL CNVGC
WL BE ENHANCED ALONG A LK INDUCED TROF THAT IS FCST BY MANY OF THE
MODELS TO CROSS THE CENTRAL KEWEENAW PENINSULA AND PERHAPS OVER THE
FAR E FM GRAND MARAIS TO WHITEFISH PT. VERY COLD AIR TO THE S OF
THIS TROF...WITH MIN TEMPS -5F TO PERHAPS -10F...WL ALSO ACCENTUATE
LAND BREEZE CNVGC. TENDED TO BUMP UP QPF OVER CONSENSUS FCST IN THIS
AREA...WHERE AN LES HEADLINE WL LIKELY BE NECESSARY. RIGHT NOW...
LOOKS LIKE WIND CHILLS WL NOT FALL TO ADVY CRITERIA /-25F/ AS WINDS
WL BE LIGHTER OVER THE INTERIOR W WHERE MIN TEMPS WL BE LOWEST.
ALTHOUGH H85 TEMPS WL BE A FEW DEGREES HIER ON MON THAN ON SUN...A
MORE W WIND COMPONENT THAT LIMITS LK SUP MODERATION SUGGESTS MAX
TEMPS WL BE NO WARMER AND PERHAPS EVEN COLDER ON MON THAN SUN. THIS
MORE BACKED FLOW WL KEEP MUCH OF THE CWA DRY TO THE S OF THE MORE
DOMINANT LES BAND THAT MAY IMPACT NRN ONTONAGON/CENTRAL HOUGHTON
COUNTY AND PERHAPS THE FAR E NEAR LK SUP.
MON NGT/TUE...MEDIUM RANGE GUIDANCE IS COMING INTO BETTER AGREEMENT
ON TIMING/TRACK OF CLIPPER TYPE SHRTWV FCST TO DIG OVER NRN MN BY
00Z TUE...OVER THE LOWER GREAT LKS AT 12Z TUE AND THEN OVER SE
ONTARIO LATE ON TUE. ALTHOUGH THE ACCOMPANYING SFC LO IS PROGGED TO
PASS TO THE S THRU WI AND LOWER MI...MODELS SHOW LLVL W FLOW ON MON
EVNG BECOMING SHARPLY CYC AND VEERING TO THE NNW ON TUE...WHICH IS
PROGGED TO ADVECT H85 TEMPS AS LO AS -22C TO -24C BACK OVER UPR MI
BY LATER ON TUE. SINCE THE DEEP LYR QVECTOR CNVGC IS PROGGED TO
IMPACT UPR MI TO THE N OF THE SHRTWV TRACK...GFS FCST SDNGS SHOW
DEEP MOISTENING DESPITE LACK OF MSTR INFLOW INTO THE AREA AHEAD OF
THE SHRTWV THAT WL LIMIT QPF AWAY FM LK SUP MOISTENING. BUT LOOKS
LIKE A HEADLINE LK ENHANCED EVENT MAY BE IN THE WORKS FOR LATE MON
NIGHT THRU MUCH OF TUE FOR THE FAVORED AREAS IMPACTED BY THE LES OFF
LK SUP. GUSTY WINDS AND INCRSGLY SMALL SN FLAKES ASSOCIATED WITH
DESCENDING DGZ MAY ALSO RESULT IN SOME VERY LO VSBYS.
EXTENDED...ON WED...WINDS WL BACK AGAIN TO A MORE W DIRECTION AS HI
PRES TRAILING THE DEPARTING CLIPPER SHRTWV SHIFTS FM THE NRN PLAINS
INTO THE OH RIVER VALLEY. WITH THE BACKING FLOW...THE PURE LES WL
BECOME MORE RESTRICTED TO THE KEWEENAW AND AREAS NEAR LK SUP FM
GRAND MARAIS TO WHITEFISH PT. SOME OF THE LONGER RANGE GUIDANCE
HINTS ANOTHER SHRTWV/SFC LO WL APRCH LATER WED/THU...WITH WAA BAND
OF SN ARRIVING TO THE N OF ASSOCIATED WARM FNT...FOLLOWED BY SOME
LES ON FRI AS A MORE MODERATELY COLD AIRMASS RETURNS. BUT EXPLICIT
MODELS SHOW CONSIDERABLE VARIABILITY DURING THIS LATE WEEK PERIOD...
SO DID NOT STRAY FM CONSENSUS FCST.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1254 PM EST SAT JAN 9 2016
LOOK FOR CONTINUED DETERIORATED CONDITIONS AT ALL SITES THROUGH THE
PERIOD...AS COLD AIR MOVING INTO THE AREA LEADS TO A PROLONGED
PERIOD OF LAKE EFFECT SNOW BEHIND A SERIES OF LOW PRESSURE SYSTEMS
TO OUR E AND HIGH PRESSURE SET UP ACROSS THE N AND CENTRAL PLAINS.
CEILINGS HAVE FALLEN TO MVFR TO HIGH END IFR /LOWEST AT IWD WHERE
THE FAVORABLE NW WINDS HAVE TAKEN HOLD. CONTINUED CALM WINDS REPORTED
AT IWD LOOK TO BE A CONTINUED TECHNICAL ISSUE FROM THE SITE. HAVE
EDITED THE LAST LINE OF THE TAF TO AMD LTD TO CLD AND VIS.
TEMPORARILY BLSN COULD BE A POSSIBILITY LATE TONIGHT THROUGH SUNDAY
MAINLY AT CMX AND SAW...WHERE THE PRESSURE GRADIENT REMAINS
STRONGEST.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 407 AM EST SAT JAN 9 2016
A BROAD SURFACE LOW OVER NORTHERN LAKE MICHIGAN WILL CONTINUE
NORTHEAST AND SLOWLY DISSIPATE TODAY WHILE A SECONDARY LOW TAKES
SHAPE IN THE SOUTHERN PLAINS. WINDS HAVE ALREADY SHIFTED TO THE
NORTHWEST OVER THE WESTERN HALF OF THE LAKE AND EXPECT THAT WIND
SHIFT TO SLIDE EAST ACROSS THE REST OF THE LAKE THROUGH THE MORNING
HOURS. AT THIS POINT...ONLY EXPECT WINDS UP TO 30KTS THROUGH THIS
EVENING...BUT AS THE SECONDARY LOW LIFTS NORTHEAST THROUGH THE
SOUTHEASTERN GREAT LAKES LATE TONIGHT AND SUNDAY MORNING...THE
GRADIENT BETWEEN THE LOW AND THE HIGH IN THE CENTRAL/NORTHERN
PLAINS WILL PRODUCE OCCASIONAL NORTHERLY GALES TO 35KTS OVER THE
EASTERN HALF OF LAKE SUPERIOR. WITH ONLY MARGINAL GALES
EXPECTED...WILL KEEP THE GALE WATCH IN PLACE AND ALLOW THE DAY
SHIFT ONE FINAL LOOK TO SEE IF THE MODELS CONTINUE TO TREND WINDS
DOWN. ALSO EXPECT A PERIOD OF FREEZING SPRAY AND MAY NEED A HEAVY
FREEZING SPRAY WARNING IF THE WINDS/WAVES STAY AT THE CURRENTLY
FORECASTED LEVELS. THE WINDS WILL QUICKLY DIMINISH SUNDAY NIGHT AS
THE LOW DEPARTS...BUT ANOTHER LOW WILL QUICKLY DROP SOUTHEAST ACROSS
THE UPPER GREAT LAKES MONDAY NIGHT AND BRING ANOTHER POTENTIAL FOR
NORTHERLY GALES TUESDAY INTO TUESDAY EVENING. BEHIND THE LOW...A
HIGH PRESSURE RIDGE WILL MOVE INTO THE AREA FOR WEDNESDAY AND
DIMINISH WINDS BELOW 25KTS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WATCH FROM LATE TONIGHT THROUGH LATE SUNDAY NIGHT FOR
LSZ249>251-266-267.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...KC
AVIATION...KF
MARINE...SRF
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1126 AM EST SAT JAN 9 2016
LATEST UPDATE...
HYDRO
.SYNOPSIS...
ISSUED AT 254 AM EST SAT JAN 9 2016
A WINTER STORM WILL AFFECT THE REGION AS RAIN CHANGES TO SNOW THIS
EVENING AND OVERNIGHT. A RAPID FALL IN TEMPERATURES WILL CAUSE A
QUICK FREEZE UP ON AREA ROADS THIS EVENING. AREAS NORTH AND WEST OF
GRAND RAPIDS CAN EXPECT 4 TO 8 INCHES OF SNOW...WHILE AREAS SOUTH
AND EAST OF GRAND RAPIDS WILL SEE 1 TO 5 INCHES OF SNOW. ALONG WITH
THE SNOW...WINDS WILL INCREASE LATE SATURDAY NIGHT AND CONTINUE INTO
SUNDAY. NORTHWEST WINDS WILL GUST TO 30-35 MPH CAUSING BLOWING AND
DRIFTING SNOW.
ANOTHER ROUND OF ACCUMULATING SNOW APPEARS LIKELY MONDAY NIGHT INTO
TUESDAY NIGHT. IT SHOULD REMAIN COLD ALL NEXT WEEK WITH DAYTIME
HIGHS ONLY 20 TO 25.
&&
.UPDATE...
ISSUED AT 1114 AM EST SAT JAN 9 2016
HAD TO TWEAK SNOWFALL AMOUNTS A BIT ACROSS THE CENTRAL FORECAST
AREA TO LINE UP BETTER WITH ADJACENT OFFICES. ADDED CALHOUN COUNTY
TO THE WINTER WEATHER ADVISORY FOR BETTER CONTINUITY.
STILL LOOKING AT A SHARP SNOWFALL GRADIENT SETTING UP OVER THE
CENTRAL OR EASTERN FORECAST AREA...BUT FALLING TEMPERATURES BEHIND
THE ARCTIC FRONT SHOULD CAUSE ENOUGH ICY TRAVEL CONDITIONS TO
JUSTIFY THE ADVISORY ACROSS MUCH OF THE EASTERN FORECAST ZONES
WHERE ACTUAL SNOW AMOUNTS BY SUNDAY EVENING COULD END UP BEING IN
THE 1 TO 2 INCH RANGE.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY NIGHT)
ISSUED AT 254 AM EST SAT JAN 9 2016
WILL ISSUE A WINTER STORM WARNING FOR THE NW HALF OF THE CWA FOR
TONIGHT AND SUNDAY. THIS WILL BE BORDERED BY AN ADVISORY TO IT/S SE.
POTENT LOW PRESSURE REMAINS ON TRACK TO IMPACT MUCH OF LOWER
MICHIGAN. CONFIDENCE REMAINS HIGH AS THE MODELS HAVE STUCK TO A
VERY SIMILAR SOLUTION FOR THE PAST 24-36 HOURS. THE STORM PATH
REMAINS INTACT...ALTHOUGH IT APPEARS SLIGHT QUICKER...REACHING JUST
WEST OF ERIE PA BY 12 SUNDAY.
THE KEY ELEMENT TO THE FORECAST WILL BE THE TEMP TREND. MODELS
SEEMS TOO WARM AS THE PCPN SETTLES IN LATE THIS AFTERNOON. UPSTREAM
OBS BACK THIS UP. IF THIS HOLDS WE WILL SEE A QUICKER CHANGE OVER
TO SNOW...AND THEREFORE HIGHER SNOW TOTALS. I BELIEVE THIS COOLER
TREND WILL HOLD FOR THE NW CWA...HOWEVER IT APPEARS THE SE WILL
STRUGGLE TO COOL AS THE SYSTEM BRINGS A SURGE OF WARM GULF AIR
THERE. SO EXPECT WE WILLS SEE A SHARP SNOW TOTALS ALONG A LINE FROM
ROUGHLY ALMA TO SOUTH HAVEN. NW OF THIS LINE THE PCPN TYPE BY EARLY
THIS EVENING SHOULD BE MAINLY SNOW...WHILE AREAS SE OF THE LINE ONLY
CHANGE OVER THROUGH TONIGHT. THEREFORE WILL ISSUE A WINTER STORM
WARNING FOR AREAS NW OF THE LINE...AN ADVISORY TO THE SE.
5TO8INCHESIN THE WARNING...3-5 IN THE ADVISORY. I WILL EXCLUDE
CALHOUN...INGHAM AND JACKSON COUNTIES WHERE ONLY 1-3 INCHES IS
EXPECTED.
THE QUICK FREEZE UP WILL BE A FACTOR IN THIS STORM CAUSING ROADS TO
ICE UP AS THE SNOW BEGINS. THE WINDS WILL BECOME A FACTOR AND IS
REALLY WHAT PUSHES THIS STORM INTO THE WARNING CATEGORY. GUST WILL
FREQUENTLY BE IN THE 30-35 MPH RANGE...AND EVEN A BIT HIGHER ALONG
THE COAST. THIS WILL CAUSE BLOWING AND DRIFTING SNOW...ESPECIALLY
AS TEMPS GET COLDER AND THE SNOW GET FLUFFIER. THE ABRUPT CHANGE IN
THE AREA/S CONDITIONS WAS ALSO A CONSIDERING FACTOR WITH THE
HEADLINES DECISIONS.
.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 254 AM EST SAT JAN 9 2016
AFTER 5 MONTHS OF UNUSUALLY WARM TEMPERATURES AND VERY LITTLE IN THE
WAY OF PERSISTENT COLD WEATHER... WE ARE IN FOR A MAJOR PATTERN
CHANGE. THIS WILL MEAN PERSISTENT LAKE EFFECT SNOW AND BELOW NORMAL
TEMPERATURES MOST OF THIS WEEK AND LIKELY BEYOND THAT. THE DAYS WITH
THE STRONGEST WINDS AND GREATEST LAKE EFFECT SNOW POTENTIAL ARE
TUESDAY THEN LATE WEDNESDAY INTO THURSDAY.
THANKS TO MASSIVE UPPER LEVEL BLOCKING WITH A CLOSED UPPER LEVEL
HIGH NORTH OF ALASKA AND A RIDGE (FORCED BY THE MJO BEING IN PHASE
8) ALONG THE WEST COAST WE WILL CONTINUE TO SEE THE NORTHERN STREAM
IMPACTING OUR WEATHER MOST OF THIS WEEK INTO NEXT WEEKEND. ACTUALLY
BY THURSDAY WE HAVE REX BLOCK OVER EASTERN NORTH AMERICA WITH AN
UPPER LEVEL HIGH OVER BAFFIN`S ISLAND AND ELONGATED CLOSED UPPER LOW
CENTERED OVER EASTERN CANADA. MEANWHILE THE WEST COAST RIDGE
PERSISTENT. SO WHAT WE WILL SEE IS A SERIES OF SHORTWAVES ROTATING
AROUND THE CANADIAN UPPER LOW THROUGH THIS WEEK THROUGH THIS COMING
WEEKEND. AS EACH COMES THROUGH THE INVERSION HEIGHT RISES AND LAKE
EFFECT SNOW WILL RAMP UP. THE FIRST OF THESE COMES THROUGH TUESDAY
MORNING THEN THE NEXT ONE IS WEDNESDAY NIGHT INTO THURSDAY MORNING.
AS THE SHORTWAVE THAT COMES FROM NORTH OF ALASKA (THIS MORNING)
DROPS INTO THE MEAN TROUGH IT HELPS CLOSE OFF AN UPPER LOW OVER
MICHIGAN BY TUESDAY EVENING. THAT RESULTS IN INVERSION HEIGHTS RISE
ABOVE 10000 FT TUESDAY MORNING AND THERE IS STRONG LIFT IN THE DGZ.
THIS WILL START AS SOUTHWEST FLOW EVENT AND TRANSITION INTO A WEST
FLOW EVENT TUESDAY DURING THE DAY. IT WILL BE WINDY IN THE AFTERNOON
WITH GUSTS TO 30 MPH MORE THAN POSSIBLE DUE TO THE SHIFTING SNOW
BANDS THE HEAVIEST SNOW WILL BE SOMEWHAT SPREAD OUT BUT THANKS TO
THE WEST WINDS DURING THE DAY TUESDAY THE BAND WILL STREAM INLAND
BETWEEN I-94 AND I-96. THE CIPS ANALOGS SHOW AT GREATER THAN 80 PCT
CHANCE OF MORE THAN 6 INCHES OF SNOW WEST OF US-131 FOR THIS EVENT.
THE NEXT SYSTEM THAT COMES THROUGH WEDNESDAY NIGHT INTO THURSDAY IS
NOT AS IMPRESSIVE BUT EVEN SO WE ARE STILL IN THE COLD AIR AND GFS
AND ECMWF ARE SHOWING GOOD LIFT AS THIS WAVE PASSES THROUGH. THIS
ONE SEEMS TO IMPACT THE SOUTHERN SECTIONS MORE THAN THE NORTHERN
ONES. EVEN SO... THE LAKE EFFECT SNOW WILL CONTINUE.
BEYOND THURSDAY THERE IS MODEL DISAGREEMENT AS TO HOW THE CANADIAN
UPPER LOW WOBBLES AROUND. THE ECMWF ROTATES ANOTHER CLOSED UPPER LOW
THOUGH THE AREA FRIDAY WHILE THE GFS HAS THAT SYSTEM STALLED OVER
NORTH DAKOTAS. WE WILL HAVE TO SEE LATER MODEL RUNS TO RESOLVE THAT
BUT ONE WAY OR THE OTHER IT WILL REMAIN COLDER THAN NORMAL AND
SIGNIFICANT SNOWFALL AMOUNTS SHOULD BE EXPECTED NEAR AND WEST OF US-
131 MONDAY AFTERNOON THROUGH THURSDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 700 AM EST SAT JAN 9 2016
I SEE TWO MAJOR AVIATION ISSUES TODAY. FIRST IS DENSE FOG. THEN WE
HAVE THE ISSUE OF RAIN CHANGING TO SNOW AND BLOWING SNOW WITH THE SYSTEM
TONIGHT INTO SUNDAY.
THE FOG HAS BEEN IN AND OUT OVERNIGHT (MOSTLY AT GRR)HOWEVER WE
CURRENTLY REMAIN IN THE CIRCULATION OF THE DEPARTING SURFACE LOW.
ONCE THAT SYSTEM LIFTS OUT OF THE AREA... AROUND 15Z OR SO...
WINDS WILL BECOME LIGHT AND VARIABLE AND I DO BELIEVE WE WILL SEE
THE FOG REALLY SET IN AND MOST OF OUR TAF SITES WILL SEE 1/2SM FG
FOR SEVERAL HOURS (SEEN ON THE RAP MODEL VISIBILITY FORECAST RUN
AFTER RUN OVERNIGHT).
BY 21Z OR SO THE DEVELOPING STORM TO OUR SOUTH WILL BE CLOSE
ENOUGH TO PUT US IN THE CIRCULATION OF THAT SYSTEM. THAT WILL
START THE RAIN AND INCREASE THE WIND...ENDING THE FOG. WE SHOULD
SEE ABOUT 12 HOURS OF MODERATE TO HEAVY PRECIPITATION AS THE
DEFORMATION ZONE OF THE SYSTEM PASSES OVERHEAD. THE HEAVIEST QPF
WILL BE JUST ON A LINE FROM SBN TO MOP. MEANWHILE THE RAIN/SNOW
LINE WILL MOVE EASTWARD...CHANGING THE RAIN TO SNOW AT MKG AND GRR BY
00Z...BUT IT MAY TAKE TILL 10Z FOR THAT RAIN TO SNOW LINE TO REACH
JXN. THIS IS SHOWN BY THE NUMEROUS RUNS OF THE RAP...HRRR...AND
GFS MODELS (ECMWF FOR THAT MATTER TOO). AS THE LOW DEEPENS WINDS
WILL INCREASE OUT OF THE NORTH AND WITH TEMPERATURES FALLING INTO
THE 20S BY 09Z OR SO... I WOULD EXPECT CONSIDERABLE BLOWING SNOW
TOO.
BOTTOM LINE...IFR /LIFR FOG THIS AFTERNOON.... THEN IFR RAIN TO
SNOW TONIGHT.
&&
.MARINE...
ISSUED AT 254 AM EST SAT JAN 9 2016
GALE WARNING HAS BEEN ISSUED AS WINDS RAMP UP QUICKLY LATE TONIGHT.
THE WINDS SHOULD SIMMER DOWN A BIT BY LATE SUNDAY EVENING AS THE
STORM PULLS AWAY.
&&
.HYDROLOGY...
ISSUED AT 1126 AM EST SAT JAN 9 2016
MINOR RIVER FLOODING CONCERNS EXIST AS WE HEAD THROUGH THE NEXT
SEVERAL DAYS. KEY QUESTIONS LINGER IN THE DETAILS...SUCH AS HOW
MUCH RUNOFF RESULTS FROM RAINFALL AND SNOWMELT...IN ADDITION TO
THE ONSET OF SUB-FREEZING TEMPERATURES.
GUIDANCE CONTINUES TO SUGGEST THAT RAINFALL WILL QUICKLY CHANGE TO
SNOW LATE THIS EVENING NEAR AND ALONG I-196...AS WELL AS NORTH AND
WEST OF GRAND RAPIDS. THE DIFFICULTY IN TIMING THIS TRANSITION
INCREASES FURTHER SOUTH AND EAST OF GRAND RAPIDS. THIS IS WHERE
MUCH OF THE CONCERN EXISTS FOR RIVERS TO HAVE QUICKER RESPONSES
AND POSSIBLY REACH/EXCEED BANKFULL. RAINFALL AND SNOWMELT HAS
ALREADY LED TO WITHIN BANK RISES AND IF MOISTURE REMAINS IN LIQUID
FORM FOR A LONGER PERIOD...WE MAY EASILY REACH BANKFULL.
FLOOD ADVISORIES HAVE BEEN ISSUED FOR EAGLE (EAGM4)...HOLT
(HHTM4)...MAPLE RAPIDS (MRPM4) AND IONIA (IONM4). CURRENT
FORECASTS INCLUDE 48HR PRECIP AND ARE RATHER CONSERVATIVE...ACCOUNTING
FOR FREEZE UP THAT MAY OCCUR QUICKER THAN EXPECTED JUST A FEW DAYS
AGO. ADDITIONAL SNOWFALL IS EXPECTED THROUGH THE WEEK WITH
TEMPERATURES THAT REMAIN BELOW FREEZING.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...WINTER STORM WARNING FROM 7 PM THIS EVENING TO 7 PM EST SUNDAY
FOR MIZ037>040-043>046-050-051-056-057-064-071.
WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 7 PM EST
SUNDAY FOR MIZ052-058-059-065-066-072-073.
LM...GALE WARNING FROM 1 AM TO 7 PM EST SUNDAY FOR LMZ844>849.
&&
$$
UPDATE...OSTUNO
SYNOPSIS...JK
SHORT TERM...JK
LONG TERM...WDM
AVIATION...WDM
HYDROLOGY...JAM
MARINE...JK
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1114 AM EST SAT JAN 9 2016
LATEST UPDATE...
UPDATE
.SYNOPSIS...
ISSUED AT 254 AM EST SAT JAN 9 2016
A WINTER STORM WILL AFFECT THE REGION AS RAIN CHANGES TO SNOW THIS
EVENING AND OVERNIGHT. A RAPID FALL IN TEMPERATURES WILL CAUSE A
QUICK FREEZE UP ON AREA ROADS THIS EVENING. AREAS NORTH AND WEST OF
GRAND RAPIDS CAN EXPECT 4 TO 8 INCHES OF SNOW...WHILE AREAS SOUTH
AND EAST OF GRAND RAPIDS WILL SEE 1 TO 5 INCHES OF SNOW. ALONG WITH
THE SNOW...WINDS WILL INCREASE LATE SATURDAY NIGHT AND CONTINUE INTO
SUNDAY. NORTHWEST WINDS WILL GUST TO 30-35 MPH CAUSING BLOWING AND
DRIFTING SNOW.
ANOTHER ROUND OF ACCUMULATING SNOW APPEARS LIKELY MONDAY NIGHT INTO
TUESDAY NIGHT. IT SHOULD REMAIN COLD ALL NEXT WEEK WITH DAYTIME
HIGHS ONLY 20 TO 25.
&&
.UPDATE...
ISSUED AT 1114 AM EST SAT JAN 9 2016
HAD TO TWEAK SNOWFALL AMOUNTS A BIT ACROSS THE CENTRAL FORECAST
AREA TO LINE UP BETTER WITH ADJACENT OFFICES. ADDED CALHOUN COUNTY
TO THE WINTER WEATHER ADVISORY FOR BETTER CONTINUITY.
STILL LOOKING AT A SHARP SNOWFALL GRADIENT SETTING UP OVER THE
CENTRAL OR EASTERN FORECAST AREA...BUT FALLING TEMPERATURES BEHIND
THE ARCTIC FRONT SHOULD CAUSE ENOUGH ICY TRAVEL CONDITIONS TO
JUSTIFY THE ADVISORY ACROSS MUCH OF THE EASTERN FORECAST ZONES
WHERE ACTUAL SNOW AMOUNTS BY SUNDAY EVENING COULD END UP BEING IN
THE 1 TO 2 INCH RANGE.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY NIGHT)
ISSUED AT 254 AM EST SAT JAN 9 2016
WILL ISSUE A WINTER STORM WARNING FOR THE NW HALF OF THE CWA FOR
TONIGHT AND SUNDAY. THIS WILL BE BORDERED BY AN ADVISORY TO IT/S SE.
POTENT LOW PRESSURE REMAINS ON TRACK TO IMPACT MUCH OF LOWER
MICHIGAN. CONFIDENCE REMAINS HIGH AS THE MODELS HAVE STUCK TO A
VERY SIMILAR SOLUTION FOR THE PAST 24-36 HOURS. THE STORM PATH
REMAINS INTACT...ALTHOUGH IT APPEARS SLIGHT QUICKER...REACHING JUST
WEST OF ERIE PA BY 12 SUNDAY.
THE KEY ELEMENT TO THE FORECAST WILL BE THE TEMP TREND. MODELS
SEEMS TOO WARM AS THE PCPN SETTLES IN LATE THIS AFTERNOON. UPSTREAM
OBS BACK THIS UP. IF THIS HOLDS WE WILL SEE A QUICKER CHANGE OVER
TO SNOW...AND THEREFORE HIGHER SNOW TOTALS. I BELIEVE THIS COOLER
TREND WILL HOLD FOR THE NW CWA...HOWEVER IT APPEARS THE SE WILL
STRUGGLE TO COOL AS THE SYSTEM BRINGS A SURGE OF WARM GULF AIR
THERE. SO EXPECT WE WILLS SEE A SHARP SNOW TOTALS ALONG A LINE FROM
ROUGHLY ALMA TO SOUTH HAVEN. NW OF THIS LINE THE PCPN TYPE BY EARLY
THIS EVENING SHOULD BE MAINLY SNOW...WHILE AREAS SE OF THE LINE ONLY
CHANGE OVER THROUGH TONIGHT. THEREFORE WILL ISSUE A WINTER STORM
WARNING FOR AREAS NW OF THE LINE...AN ADVISORY TO THE SE.
5TO8INCHESIN THE WARNING...3-5 IN THE ADVISORY. I WILL EXCLUDE
CALHOUN...INGHAM AND JACKSON COUNTIES WHERE ONLY 1-3 INCHES IS
EXPECTED.
THE QUICK FREEZE UP WILL BE A FACTOR IN THIS STORM CAUSING ROADS TO
ICE UP AS THE SNOW BEGINS. THE WINDS WILL BECOME A FACTOR AND IS
REALLY WHAT PUSHES THIS STORM INTO THE WARNING CATEGORY. GUST WILL
FREQUENTLY BE IN THE 30-35 MPH RANGE...AND EVEN A BIT HIGHER ALONG
THE COAST. THIS WILL CAUSE BLOWING AND DRIFTING SNOW...ESPECIALLY
AS TEMPS GET COLDER AND THE SNOW GET FLUFFIER. THE ABRUPT CHANGE IN
THE AREA/S CONDITIONS WAS ALSO A CONSIDERING FACTOR WITH THE
HEADLINES DECISIONS.
.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 254 AM EST SAT JAN 9 2016
AFTER 5 MONTHS OF UNUSUALLY WARM TEMPERATURES AND VERY LITTLE IN THE
WAY OF PERSISTENT COLD WEATHER... WE ARE IN FOR A MAJOR PATTERN
CHANGE. THIS WILL MEAN PERSISTENT LAKE EFFECT SNOW AND BELOW NORMAL
TEMPERATURES MOST OF THIS WEEK AND LIKELY BEYOND THAT. THE DAYS WITH
THE STRONGEST WINDS AND GREATEST LAKE EFFECT SNOW POTENTIAL ARE
TUESDAY THEN LATE WEDNESDAY INTO THURSDAY.
THANKS TO MASSIVE UPPER LEVEL BLOCKING WITH A CLOSED UPPER LEVEL
HIGH NORTH OF ALASKA AND A RIDGE (FORCED BY THE MJO BEING IN PHASE
8) ALONG THE WEST COAST WE WILL CONTINUE TO SEE THE NORTHERN STREAM
IMPACTING OUR WEATHER MOST OF THIS WEEK INTO NEXT WEEKEND. ACTUALLY
BY THURSDAY WE HAVE REX BLOCK OVER EASTERN NORTH AMERICA WITH AN
UPPER LEVEL HIGH OVER BAFFIN`S ISLAND AND ELONGATED CLOSED UPPER LOW
CENTERED OVER EASTERN CANADA. MEANWHILE THE WEST COAST RIDGE
PERSISTENT. SO WHAT WE WILL SEE IS A SERIES OF SHORTWAVES ROTATING
AROUND THE CANADIAN UPPER LOW THROUGH THIS WEEK THROUGH THIS COMING
WEEKEND. AS EACH COMES THROUGH THE INVERSION HEIGHT RISES AND LAKE
EFFECT SNOW WILL RAMP UP. THE FIRST OF THESE COMES THROUGH TUESDAY
MORNING THEN THE NEXT ONE IS WEDNESDAY NIGHT INTO THURSDAY MORNING.
AS THE SHORTWAVE THAT COMES FROM NORTH OF ALASKA (THIS MORNING)
DROPS INTO THE MEAN TROUGH IT HELPS CLOSE OFF AN UPPER LOW OVER
MICHIGAN BY TUESDAY EVENING. THAT RESULTS IN INVERSION HEIGHTS RISE
ABOVE 10000 FT TUESDAY MORNING AND THERE IS STRONG LIFT IN THE DGZ.
THIS WILL START AS SOUTHWEST FLOW EVENT AND TRANSITION INTO A WEST
FLOW EVENT TUESDAY DURING THE DAY. IT WILL BE WINDY IN THE AFTERNOON
WITH GUSTS TO 30 MPH MORE THAN POSSIBLE DUE TO THE SHIFTING SNOW
BANDS THE HEAVIEST SNOW WILL BE SOMEWHAT SPREAD OUT BUT THANKS TO
THE WEST WINDS DURING THE DAY TUESDAY THE BAND WILL STREAM INLAND
BETWEEN I-94 AND I-96. THE CIPS ANALOGS SHOW AT GREATER THAN 80 PCT
CHANCE OF MORE THAN 6 INCHES OF SNOW WEST OF US-131 FOR THIS EVENT.
THE NEXT SYSTEM THAT COMES THROUGH WEDNESDAY NIGHT INTO THURSDAY IS
NOT AS IMPRESSIVE BUT EVEN SO WE ARE STILL IN THE COLD AIR AND GFS
AND ECMWF ARE SHOWING GOOD LIFT AS THIS WAVE PASSES THROUGH. THIS
ONE SEEMS TO IMPACT THE SOUTHERN SECTIONS MORE THAN THE NORTHERN
ONES. EVEN SO... THE LAKE EFFECT SNOW WILL CONTINUE.
BEYOND THURSDAY THERE IS MODEL DISAGREEMENT AS TO HOW THE CANADIAN
UPPER LOW WOBBLES AROUND. THE ECMWF ROTATES ANOTHER CLOSED UPPER LOW
THOUGH THE AREA FRIDAY WHILE THE GFS HAS THAT SYSTEM STALLED OVER
NORTH DAKOTAS. WE WILL HAVE TO SEE LATER MODEL RUNS TO RESOLVE THAT
BUT ONE WAY OR THE OTHER IT WILL REMAIN COLDER THAN NORMAL AND
SIGNIFICANT SNOWFALL AMOUNTS SHOULD BE EXPECTED NEAR AND WEST OF US-
131 MONDAY AFTERNOON THROUGH THURSDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 700 AM EST SAT JAN 9 2016
I SEE TWO MAJOR AVIATION ISSUES TODAY. FIRST IS DENSE FOG. THEN WE
HAVE THE ISSUE OF RAIN CHANGING TO SNOW AND BLOWING SNOW WITH THE SYSTEM
TONIGHT INTO SUNDAY.
THE FOG HAS BEEN IN AND OUT OVERNIGHT (MOSTLY AT GRR)HOWEVER WE
CURRENTLY REMAIN IN THE CIRCULATION OF THE DEPARTING SURFACE LOW.
ONCE THAT SYSTEM LIFTS OUT OF THE AREA... AROUND 15Z OR SO...
WINDS WILL BECOME LIGHT AND VARIABLE AND I DO BELIEVE WE WILL SEE
THE FOG REALLY SET IN AND MOST OF OUR TAF SITES WILL SEE 1/2SM FG
FOR SEVERAL HOURS (SEEN ON THE RAP MODEL VISIBILITY FORECAST RUN
AFTER RUN OVERNIGHT).
BY 21Z OR SO THE DEVELOPING STORM TO OUR SOUTH WILL BE CLOSE
ENOUGH TO PUT US IN THE CIRCULATION OF THAT SYSTEM. THAT WILL
START THE RAIN AND INCREASE THE WIND...ENDING THE FOG. WE SHOULD
SEE ABOUT 12 HOURS OF MODERATE TO HEAVY PRECIPITATION AS THE
DEFORMATION ZONE OF THE SYSTEM PASSES OVERHEAD. THE HEAVIEST QPF
WILL BE JUST ON A LINE FROM SBN TO MOP. MEANWHILE THE RAIN/SNOW
LINE WILL MOVE EASTWARD...CHANGING THE RAIN TO SNOW AT MKG AND GRR BY
00Z...BUT IT MAY TAKE TILL 10Z FOR THAT RAIN TO SNOW LINE TO REACH
JXN. THIS IS SHOWN BY THE NUMEROUS RUNS OF THE RAP...HRRR...AND
GFS MODELS (ECMWF FOR THAT MATTER TOO). AS THE LOW DEEPENS WINDS
WILL INCREASE OUT OF THE NORTH AND WITH TEMPERATURES FALLING INTO
THE 20S BY 09Z OR SO... I WOULD EXPECT CONSIDERABLE BLOWING SNOW
TOO.
BOTTOM LINE...IFR /LIFR FOG THIS AFTERNOON.... THEN IFR RAIN TO
SNOW TONIGHT.
&&
.MARINE...
ISSUED AT 254 AM EST SAT JAN 9 2016
GALE WARNING HAS BEEN ISSUED AS WINDS RAMP UP QUICKLY LATE TONIGHT.
THE WINDS SHOULD SIMMER DOWN A BIT BY LATE SUNDAY EVENING AS THE
STORM PULLS AWAY.
&&
.HYDROLOGY...
ISSUED AT 134 PM EST FRI JAN 8 2016
THERE IS INCREASING CONCERN FOR MINOR RIVER FLOODING HEADING
THROUGH THE NEXT SEVERAL DAYS. RIVER RISES ARE LIKELY WITH A FEW
LOCATIONS THAT HAVE THE POTENTIAL TO REACH BANKFULL. THE MAIN
QUESTIONS TO BE ANSWERED HAVE TO DEAL WITH THE AMOUNT OF RUNOFF
DUE TO SNOWMELT AND RESULTING LIQUID PRECIPITATION THROUGH LATE
SATURDAY EVENING.
THE FIRST WAVE OF MOISTURE WILL MOVE THROUGH AHEAD OF A STORM
SYSTEM CURRENTLY OVER MISSOURI/ILLINOIS. RAINFALL POTENTIAL EXISTS
NOW THROUGH MUCH OF SATURDAY. THE KEY TO HOW QUICKLY RIVERS
RESPOND LIES IN THE DETAILS OF REALIZED TOTALS...LEADING UP TO THE
THE TRANSITION TO SNOW SATURDAY NIGHT. ONCE COLDER AIR MOVES IN
LATE SATURDAY INTO SUNDAY...SUB-FREEZING TEMPS MAY BRING A HALT TO
MUCH OF THE RUNOFF AS POTENTIAL RUNOFF FREEZES. PRECIPITATION IS
THEN EXPECTED TO REMAIN LARGELY LOCKED UP IN SNOW ACCUMULATIONS.
THE WEEK AHEAD WILL BRING ADDITIONAL SNOW ACCUMULATIONS...BUT
TEMPERATURES SHOULD BE WELL BELOW FREEZING THROUGH THURSDAY.
CONDITIONS WILL NEED TO BE MONITORED THROUGH THE NEXT FEW DAYS FOR
ANY RISES THAT HAVE THE POTENTIAL TO EXCEED BANKFULL.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...WINTER STORM WARNING FROM 7 PM THIS EVENING TO 7 PM EST SUNDAY
FOR MIZ037>040-043>046-050-051-056-057-064-071.
WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 7 PM EST
SUNDAY FOR MIZ052-058-059-065-066-072-073.
LM...GALE WARNING FROM 1 AM TO 7 PM EST SUNDAY FOR LMZ844>849.
&&
$$
UPDATE...OSTUNO
SYNOPSIS...JK
SHORT TERM...JK
LONG TERM...WDM
AVIATION...WDM
HYDROLOGY...JAM
MARINE...JK
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
701 AM EST SAT JAN 9 2016
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 254 AM EST SAT JAN 9 2016
A WINTER STORM WILL AFFECT THE REGION AS RAIN CHANGES TO SNOW THIS
EVENING AND OVERNIGHT. A RAPID FALL IN TEMPERATURES WILL CAUSE A
QUICK FREEZE UP ON AREA ROADS THIS EVENING. AREAS NORTH AND WEST OF
GRAND RAPIDS CAN EXPECT 4 TO 8 INCHES OF SNOW...WHILE AREAS SOUTH
AND EAST OF GRAND RAPIDS WILL SEE 1 TO 5 INCHES OF SNOW. ALONG WITH
THE SNOW...WINDS WILL INCREASE LATE SATURDAY NIGHT AND CONTINUE INTO
SUNDAY. NORTHWEST WINDS WILL GUST TO 30-35 MPH CAUSING BLOWING AND
DRIFTING SNOW.
ANOTHER ROUND OF ACCUMULATING SNOW APPEARS LIKELY MONDAY NIGHT INTO
TUESDAY NIGHT. IT SHOULD REMAIN COLD ALL NEXT WEEK WITH DAYTIME
HIGHS ONLY 20 TO 25.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY NIGHT)
ISSUED AT 254 AM EST SAT JAN 9 2016
WILL ISSUE A WINTER STORM WARNING FOR THE NW HALF OF THE CWA FOR
TONIGHT AND SUNDAY. THIS WILL BE BORDERED BY AN ADVISORY TO IT/S SE.
POTENT LOW PRESSURE REMAINS ON TRACK TO IMPACT MUCH OF LOWER
MICHIGAN. CONFIDENCE REMAINS HIGH AS THE MODELS HAVE STUCK TO A
VERY SIMILAR SOLUTION FOR THE PAST 24-36 HOURS. THE STORM PATH
REMAINS INTACT...ALTHOUGH IT APPEARS SLIGHT QUICKER...REACHING JUST
WEST OF ERIE PA BY 12 SUNDAY.
THE KEY ELEMENT TO THE FORECAST WILL BE THE TEMP TREND. MODELS
SEEMS TOO WARM AS THE PCPN SETTLES IN LATE THIS AFTERNOON. UPSTREAM
OBS BACK THIS UP. IF THIS HOLDS WE WILL SEE A QUICKER CHANGE OVER
TO SNOW...AND THEREFORE HIGHER SNOW TOTALS. I BELIEVE THIS COOLER
TREND WILL HOLD FOR THE NW CWA...HOWEVER IT APPEARS THE SE WILL
STRUGGLE TO COOL AS THE SYSTEM BRINGS A SURGE OF WARM GULF AIR
THERE. SO EXPECT WE WILLS SEE A SHARP SNOW TOTALS ALONG A LINE FROM
ROUGHLY ALMA TO SOUTH HAVEN. NW OF THIS LINE THE PCPN TYPE BY EARLY
THIS EVENING SHOULD BE MAINLY SNOW...WHILE AREAS SE OF THE LINE ONLY
CHANGE OVER THROUGH TONIGHT. THEREFORE WILL ISSUE A WINTER STORM
WARNING FOR AREAS NW OF THE LINE...AN ADVISORY TO THE SE.
5TO8INCHESIN THE WARNING...3-5 IN THE ADVISORY. I WILL EXCLUDE
CALHOUN...INGHAM AND JACKSON COUNTIES WHERE ONLY 1-3 INCHES IS
EXPECTED.
THE QUICK FREEZE UP WILL BE A FACTOR IN THIS STORM CAUSING ROADS TO
ICE UP AS THE SNOW BEGINS. THE WINDS WILL BECOME A FACTOR AND IS
REALLY WHAT PUSHES THIS STORM INTO THE WARNING CATEGORY. GUST WILL
FREQUENTLY BE IN THE 30-35 MPH RANGE...AND EVEN A BIT HIGHER ALONG
THE COAST. THIS WILL CAUSE BLOWING AND DRIFTING SNOW...ESPECIALLY
AS TEMPS GET COLDER AND THE SNOW GET FLUFFIER. THE ABRUPT CHANGE IN
THE AREA/S CONDITIONS WAS ALSO A CONSIDERING FACTOR WITH THE
HEADLINES DECISIONS.
.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 254 AM EST SAT JAN 9 2016
AFTER 5 MONTHS OF UNUSUALLY WARM TEMPERATURES AND VERY LITTLE IN THE
WAY OF PERSISTENT COLD WEATHER... WE ARE IN FOR A MAJOR PATTERN
CHANGE. THIS WILL MEAN PERSISTENT LAKE EFFECT SNOW AND BELOW NORMAL
TEMPERATURES MOST OF THIS WEEK AND LIKELY BEYOND THAT. THE DAYS WITH
THE STRONGEST WINDS AND GREATEST LAKE EFFECT SNOW POTENTIAL ARE
TUESDAY THEN LATE WEDNESDAY INTO THURSDAY.
THANKS TO MASSIVE UPPER LEVEL BLOCKING WITH A CLOSED UPPER LEVEL
HIGH NORTH OF ALASKA AND A RIDGE (FORCED BY THE MJO BEING IN PHASE
8) ALONG THE WEST COAST WE WILL CONTINUE TO SEE THE NORTHERN STREAM
IMPACTING OUR WEATHER MOST OF THIS WEEK INTO NEXT WEEKEND. ACTUALLY
BY THURSDAY WE HAVE REX BLOCK OVER EASTERN NORTH AMERICA WITH AN
UPPER LEVEL HIGH OVER BAFFIN`S ISLAND AND ELONGATED CLOSED UPPER LOW
CENTERED OVER EASTERN CANADA. MEANWHILE THE WEST COAST RIDGE
PERSISTENT. SO WHAT WE WILL SEE IS A SERIES OF SHORTWAVES ROTATING
AROUND THE CANADIAN UPPER LOW THROUGH THIS WEEK THROUGH THIS COMING
WEEKEND. AS EACH COMES THROUGH THE INVERSION HEIGHT RISES AND LAKE
EFFECT SNOW WILL RAMP UP. THE FIRST OF THESE COMES THROUGH TUESDAY
MORNING THEN THE NEXT ONE IS WEDNESDAY NIGHT INTO THURSDAY MORNING.
AS THE SHORTWAVE THAT COMES FROM NORTH OF ALASKA (THIS MORNING)
DROPS INTO THE MEAN TROUGH IT HELPS CLOSE OFF AN UPPER LOW OVER
MICHIGAN BY TUESDAY EVENING. THAT RESULTS IN INVERSION HEIGHTS RISE
ABOVE 10000 FT TUESDAY MORNING AND THERE IS STRONG LIFT IN THE DGZ.
THIS WILL START AS SOUTHWEST FLOW EVENT AND TRANSITION INTO A WEST
FLOW EVENT TUESDAY DURING THE DAY. IT WILL BE WINDY IN THE AFTERNOON
WITH GUSTS TO 30 MPH MORE THAN POSSIBLE DUE TO THE SHIFTING SNOW
BANDS THE HEAVIEST SNOW WILL BE SOMEWHAT SPREAD OUT BUT THANKS TO
THE WEST WINDS DURING THE DAY TUESDAY THE BAND WILL STREAM INLAND
BETWEEN I-94 AND I-96. THE CIPS ANALOGS SHOW AT GREATER THAN 80 PCT
CHANCE OF MORE THAN 6 INCHES OF SNOW WEST OF US-131 FOR THIS EVENT.
THE NEXT SYSTEM THAT COMES THROUGH WEDNESDAY NIGHT INTO THURSDAY IS
NOT AS IMPRESSIVE BUT EVEN SO WE ARE STILL IN THE COLD AIR AND GFS
AND ECMWF ARE SHOWING GOOD LIFT AS THIS WAVE PASSES THROUGH. THIS
ONE SEEMS TO IMPACT THE SOUTHERN SECTIONS MORE THAN THE NORTHERN
ONES. EVEN SO... THE LAKE EFFECT SNOW WILL CONTINUE.
BEYOND THURSDAY THERE IS MODEL DISAGREEMENT AS TO HOW THE CANADIAN
UPPER LOW WOBBLES AROUND. THE ECMWF ROTATES ANOTHER CLOSED UPPER LOW
THOUGH THE AREA FRIDAY WHILE THE GFS HAS THAT SYSTEM STALLED OVER
NORTH DAKOTAS. WE WILL HAVE TO SEE LATER MODEL RUNS TO RESOLVE THAT
BUT ONE WAY OR THE OTHER IT WILL REMAIN COLDER THAN NORMAL AND
SIGNIFICANT SNOWFALL AMOUNTS SHOULD BE EXPECTED NEAR AND WEST OF US-
131 MONDAY AFTERNOON THROUGH THURSDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 700 AM EST SAT JAN 9 2016
I SEE TWO MAJOR AVIATION ISSUES TODAY. FIRST IS DENSE FOG. THEN WE
HAVE THE ISSUE OF RAIN CHANGING TO SNOW AND BLOWING SNOW WITH THE SYSTEM
TONIGHT INTO SUNDAY.
THE FOG HAS BEEN IN AND OUT OVERNIGHT (MOSTLY AT GRR)HOWEVER WE
CURRENTLY REMAIN IN THE CIRCULATION OF THE DEPARTING SURFACE LOW.
ONCE THAT SYSTEM LIFTS OUT OF THE AREA... AROUND 15Z OR SO...
WINDS WILL BECOME LIGHT AND VARIABLE AND I DO BELIEVE WE WILL SEE
THE FOG REALLY SET IN AND MOST OF OUR TAF SITES WILL SEE 1/2SM FG
FOR SEVERAL HOURS (SEEN ON THE RAP MODEL VISIBILITY FORECAST RUN
AFTER RUN OVERNIGHT).
BY 21Z OR SO THE DEVELOPING STORM TO OUR SOUTH WILL BE CLOSE
ENOUGH TO PUT US IN THE CIRCULATION OF THAT SYSTEM. THAT WILL
START THE RAIN AND INCREASE THE WIND...ENDING THE FOG. WE SHOULD
SEE ABOUT 12 HOURS OF MODERATE TO HEAVY PRECIPITATION AS THE
DEFORMATION ZONE OF THE SYSTEM PASSES OVERHEAD. THE HEAVIEST QPF
WILL BE JUST ON A LINE FROM SBN TO MOP. MEANWHILE THE RAIN/SNOW
LINE WILL MOVE EASTWARD...CHANGING THE RAIN TO SNOW AT MKG AND GRR BY
00Z...BUT IT MAY TAKE TILL 10Z FOR THAT RAIN TO SNOW LINE TO REACH
JXN. THIS IS SHOWN BY THE NUMEROUS RUNS OF THE RAP...HRRR...AND
GFS MODELS (ECMWF FOR THAT MATTER TOO). AS THE LOW DEEPENS WINDS
WILL INCREASE OUT OF THE NORTH AND WITH TEMPERATURES FALLING INTO
THE 20S BY 09Z OR SO... I WOULD EXPECT CONSIDERABLE BLOWING SNOW
TOO.
BOTTOM LINE...IFR /LIFR FOG THIS AFTERNOON.... THEN IFR RAIN TO
SNOW TONIGHT.
&&
.MARINE...
ISSUED AT 254 AM EST SAT JAN 9 2016
GALE WARNING HAS BEEN ISSUED AS WINDS RAMP UP QUICKLY LATE TONIGHT.
THE WINDS SHOULD SIMMER DOWN A BIT BY LATE SUNDAY EVENING AS THE
STORM PULLS AWAY.
&&
.HYDROLOGY...
ISSUED AT 134 PM EST FRI JAN 8 2016
THERE IS INCREASING CONCERN FOR MINOR RIVER FLOODING HEADING
THROUGH THE NEXT SEVERAL DAYS. RIVER RISES ARE LIKELY WITH A FEW
LOCATIONS THAT HAVE THE POTENTIAL TO REACH BANKFULL. THE MAIN
QUESTIONS TO BE ANSWERED HAVE TO DEAL WITH THE AMOUNT OF RUNOFF
DUE TO SNOWMELT AND RESULTING LIQUID PRECIPITATION THROUGH LATE
SATURDAY EVENING.
THE FIRST WAVE OF MOISTURE WILL MOVE THROUGH AHEAD OF A STORM
SYSTEM CURRENTLY OVER MISSOURI/ILLINOIS. RAINFALL POTENTIAL EXISTS
NOW THROUGH MUCH OF SATURDAY. THE KEY TO HOW QUICKLY RIVERS
RESPOND LIES IN THE DETAILS OF REALIZED TOTALS...LEADING UP TO THE
THE TRANSITION TO SNOW SATURDAY NIGHT. ONCE COLDER AIR MOVES IN
LATE SATURDAY INTO SUNDAY...SUB-FREEZING TEMPS MAY BRING A HALT TO
MUCH OF THE RUNOFF AS POTENTIAL RUNOFF FREEZES. PRECIPITATION IS
THEN EXPECTED TO REMAIN LARGELY LOCKED UP IN SNOW ACCUMULATIONS.
THE WEEK AHEAD WILL BRING ADDITIONAL SNOW ACCUMULATIONS...BUT
TEMPERATURES SHOULD BE WELL BELOW FREEZING THROUGH THURSDAY.
CONDITIONS WILL NEED TO BE MONITORED THROUGH THE NEXT FEW DAYS FOR
ANY RISES THAT HAVE THE POTENTIAL TO EXCEED BANKFULL.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...WINTER STORM WARNING FROM 7 PM THIS EVENING TO 7 PM EST SUNDAY
FOR MIZ037>040-043>046-050-051-056-057-064-071.
WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 7 PM EST
SUNDAY FOR MIZ052-058-059-065-066-072.
LM...GALE WARNING FROM 1 AM TO 7 PM EST SUNDAY FOR LMZ844>849.
&&
$$
SYNOPSIS...JK
SHORT TERM...JK
LONG TERM...WDM
AVIATION...WDM
HYDROLOGY...JAM
MARINE...JK
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
645 AM EST SAT JAN 9 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 407 AM EST SAT JAN 9 2016
MUCH COLDER AIR WILL BEGIN SURGING INTO THE AREA TODAY AND LEAD TO
BELOW NORMAL TEMPERATURES (WITH LAKE EFFECT SNOW) THROUGH AT LEAST
THE MIDDLE OF THE UPCOMING WORK WEEK. THE COLD AIR IS NOW STARTING
TO MOVE INTO THE WESTERN U.P. (RAP ANALYSIS SHOWING 850MB TEMPS
AROUND -7C AND -12C UPSTREAM IN THE MINNESOTA ARROWHEAD) AND THAT
WILL CONTINUE ACROSS THE AREA TODAY. BEFORE THAT OCCURS...A SURFACE
LOW IS CURRENTLY LOCATED OVER THE EASTERN U.P. AND IS CONTINUING TO
PRODUCE PRECIPITATION AS A SHORTWAVE LIFTS NORTHEAST THROUGH THE
AREA. WHILE MUCH OF THE PRECIPITATION OVER THE EASTERN U.P. FELL AS
RAIN THROUGH THE EVENING...HAVE BEEN SEEING A TRANSITION TO SNOW NOW
AS THE COLDER AIR IS STARTING TO WORK INTO THAT AREA (3AM METARS
SHOW KISQ IS THE ONLY SITE HANGING ON TO RAIN). EVENING SHIFT
FOLLOWED THE WETBULB0 HEIGHTS FROM THE RAP FOR THE RAIN/SNOW
TRANSITION AND THAT STILL SEEMS REASONABLE WITH THE LATEST RUNS.
HAVE FOLLOWED THAT WHICH TRANSITIONS THE LINGERING PRECIPITATION
OVER THE EAST TO SNOW BY THROUGH 5-6AM. OVER THE WEST HALF...HAVE
SEEN A LITTLE BIT OF A LULL (LIGHT SNOW FARTHER TO THE SOUTHWEST IN
SOUTHWESTERN WISCONSIN TIED WITH BETTER MOISTURE AND TRAILING COLD
FRONT)...BUT WITH THE COLDER AIR MOVING INTO THE AREA...VISIBILITIES
STARTED TO FALL WITH SNOW AT KIWD/KCMX AROUND 1AM AND HAVE BEEN
BOUNCING THROUGH THE NIGHT (LIKELY MORE TIED WITH THE LIGHT SNOW
SHOWERS MOVING IN FROM WISCONSIN THAN PURE LAKE EFFECT AT THIS
POINT). 3AM TEMPERATURES ARE STILL HOLDING ON TO THE LOWER 30S OVER
THE EASTERN 2/3RDS OF THE U.P. AND IN THE UPPER 20S TO THE WEST OF
THAT.
WITH THE COLDER AIR SURGING IN TODAY...EXPECT A TRANSITION TO PURE
LES THROUGH THE MORNING FOR THE NORTHERLY WIND SNOWBELTS BEFORE
GRADUALLY TRANSITIONING TO THE NORTHWEST WIND AREAS THROUGH THE
AFTERNOON. INVERSION HEIGHTS ARE FORECASTED TO BE AROUND 5KFT WHICH
IS SOMEWHAT LIMITING...BUT THE CLOUD WILL MOVE ENTIRELY WITHIN THE
DGZ THIS AFTERNOON AND WITH WINDS GENERALLY IN THE 15-25KT RANGE
THERE WON/T BE TOO MUCH FRACTURING. THUS...HAVE TRENDED SNOW RATIOS
UP INTO THE UPPER 20S AND WOULDN/T BE SURPRISED IF SOME LOCATIONS
END UP IN THE 30S TO 1 RANGE BASED OFF PAST SITUATIONS HERE AT OUR
OFFICE THAT HAVE YIELDED SNOW RATIOS AT OR EVEN ABOVE THOSE VALUES.
THE LOWER INVERSION HEIGHTS WILL LIKELY LIMIT THE OVERALL STRENGTH
OF THE LAKE EFFECT...BUT WITH RATIOS THAT HIGH STILL EXPECT
OCCASIONAL MODERATE SNOWFALL. HAVE SNOWFALL AMOUNTS OF 1 TO 4 INCHES
TODAY OVER THE FAVORED AREAS OVER THE FAR WESTERN U.P....WITH THE
GREATEST AMOUNTS OVER THE HIGHER TERRAIN OF GOGEBIC/ONTONAGON
COUNTIES. ONE OTHER LIMITING FACTOR FOR TODAY IS THAT THERE WILL BE
ENOUGH BACKING OF THE WINDS FROM NORTH-NORTHWEST TO NORTHWEST TODAY
TO MOVE THE BANDS AROUND ENOUGH TO LIMIT THE RESIDENCE TIME OF THE
STRONGER BANDS IN ANY ONE LOCATION. FARTHER TO THE EAST...EXPECT
SOME LAKE ENHANCEMENT NEAR LAKE SUPERIOR THROUGH THE DAY WITH THE
NORTH AND EVENTUALLY NORTHWEST WINDS...BUT INVERSION STRUGGLE TO
RISE MUCH ABOVE 4KFT WITH LESS FAVORABLE MOISTURE. THUS...DON/T
EXPECT MUCH MORE THAN A LIGHT DUSTING TO AN INCH OF SNOW TODAY THERE
AND EXPECT SCATTERED SNOW SHOWERS AND MAYBE A DUSTING OF SNOW FOR
THE REST OF THE U.P. AS THE COLD FRONT MOVES THROUGH AND THE SNOW
SHOWERS IN WISCONSIN SLIDE EAST-NORTHEAST THROUGH THE AREA. FINALLY
FOR TEMPERATURES...EXPECT STEADILY FALLING TEMPERATURES THROUGH THE
DAY...WITH VALUES AROUND SUNSET RANGING FROM THE MID TEENS OVER THE
WEST AND UPPER 20S OVER THE EAST.
FOR TONIGHT...EXPECT THE LAKE EFFECT TO CONTINUE FOR AREAS NEAR LAKE
SUPERIOR AS THE WINDS VEER BACK TO A MORE NORTHERLY DIRECTION IN
RESPONSE TO A SURFACE RIDGE TRYING TO NOSE INTO THE AREA AND A
SURFACE LOW LIFTING NORTH INTO THE LOWER GREAT LAKES. 850MB TEMPS
CONTINUE TO FALL THROUGH THE NIGHT (DOWN TO -21C OVER THE
WEST)...PUSHING THE CLOUD LAYER OUT OF THE DGZ. THAT WILL TRANSITION
THE SNOW FLAKE SIZE AND RATIOS DOWN THROUGH THE NIGHT. INVERSION
HEIGHTS STILL STAY IN THE 5-6KFT RANGE...SO STILL EXPECT LIGHT TO
OCCASIONALLY MODERATE LAKE EFFECT TO OCCUR AND HAVE ANOTHER 1-4
INCHES OF SNOW FOR THE SAME AREAS OUT WEST. THE EAST WILL SEE A
COMBINATION OF TWO FEATURES FOR TONIGHT. FIRST...THE AREA WILL BE
BRUSHED BY SNOW ASSOCIATED WITH THE SURFACE LOW LIFTING NORTHEAST
THROUGH THE EASTERN GREAT LAKES. THE HEAVIEST SNOW WILL OCCUR JUST
TO THE SOUTHEAST OF THE AREA...BUT COULD SEE A LIGHT DUSTING OVER
SOUTHERN SCHOOLCRAFT AND SOUTHERN LUCE COUNTIES. THEN FOR THE LAKE
EFFECT AREAS CLOSER TO LAKE SUPERIOR...THINK THINGS WILL INTENSIFY
THROUGH THE NIGHT AS THE COLDER AIR FINALLY ARRIVES...RAISING
INVERSION HEIGHTS TO 5-6KFT AND PUTS THE CLOUD WITHIN THE DGZ.
EXPECT SNOWFALL AMOUNTS TO BE SIMILAR TO OUT WEST IN THE FAVORED
TIME COINCIDING WITH THE CLOUD IN THE DGZ WITH 1 TO 3 INCHES OF
SNOW. WHILE WINDS WILL BE PICKING UP OVER THE EAST...THINK THE AREA
WILL NEED SOME TIME TO ACCUMULATE SNOW (AFTER THE RAIN THIS EVENING)
BEFORE THE BLOWING SNOW WILL REALLY PICKUP.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 349 AM EST SAT JAN 9 2016
MEDIUM/EXTENDED RANGE GUIDANCE CONTINUES TO INDICATE A HI AMPLITUDE
WRN NAMERICA UPR RDG/ERN TROF WL DOMINATE THE COMING WEEK...
RESULTING IN BLO NORMAL TO WELL BLO NORMAL TEMPS FOR UPR MI MOST OF
THE TIME. LES WL BE COMMON DURING MUCH OF THIS TIME AS THE COLD
ARCTIC AIR FLOWS OVER THE RELATIVELY WARM WATERS OF LK SUP.
SUN...SINCE SHRTWV LIFTING NEWD FM THE LOWER MS RIVER VALLEY TOWARD
THE UPR OH RIVER VALLY AT 12Z SUN IS FCST TO REMAIN OUT OF PHASE
WITH ARCTIC BRANCH TROF SHIFTING INTO THE WRN GREAT LKS...ASSOCIATED
SFC LO AND BULK OF DYNAMIC SUPPORT ASSOCIATED WITH THE SHRTWV/
DEEPER MSTR/HEAVIER PCPN ARE FCST TO REMAIN MAINLY TO THE E OF THE
CWA. HOWEVER...AS CYC NNW SLOWLY BACK NW FLOW DRAWS H85 TEMPS IN THE
-20C TO -23C RANGE INTO THE UPR LKS...WL FCST CATEGORICAL POPS FOR
LES IN THE FAVORED SN BELTS NEAR LK SUP. BUT THE INTENSITY OF THIS
LES WL BE LIMITED BY RATHER LO INVRN BASE FCST NEAR H85 AND INCRSGLY
POOR SN GROWTH ASSOCIATED WITH THE ARRIVAL OF THE VERY COLD AIR THAT
WL PUSH THE DGZ TO NEAR THE SFC. DOWNSLOPE NATURE OF THE BACKING
LLVL NW FLOW WL BRING DRY WX TO THE SCENTRAL. WITH THE INFLUX OF THE
ARCTIC AIR...MAX TEMPS ON SUN WL HOLD IN THE SINGLE DIGITS ABOVE 0F
OVER MUCH OF THE W HALF.
SUN NGT/MON...NW LLVL WINDS AT 00Z MON ARE FCST TO BACK SLOWLY AS
THE DEEPENING SFC LO EXITS TO THE NE THRU QUEBEC AND COLD SFC HI
PRES IN THE PLAINS SHIFTS INTO THE LOWER MS RIVER VALLEY IN ADVANCE
OF ANOTHER SHRTWV WITHIN THE NW FLOW ALF DIGGING SEWD TOWARD THE UPR
MS RIVER VALLEY. H85 TEMPS ARE FCST TO MODERATE A FEW DEGREES TO
-18C TO -21C. ALTHOUGH THE INCRSG H85 TEMPS WL ALLOW FOR BETTER SN
GROWTH...THE SHIFTING WINDS SHOULD TEND TO LIMIT BAND RESIDENCE
TIME/PURE LES ACCUMS. HOWEVER...THERE MAY BE SOME MDT LES OVER NRN
ONTONAGON/CENTRAL HOUGHTON COUNTY WHERE MORE PERSISTENT LLVL CNVGC
WL BE ENHANCED ALONG A LK INDUCED TROF THAT IS FCST BY MANY OF THE
MODELS TO CROSS THE CENTRAL KEWEENAW PENINSULA AND PERHAPS OVER THE
FAR E FM GRAND MARAIS TO WHITEFISH PT. VERY COLD AIR TO THE S OF
THIS TROF...WITH MIN TEMPS -5F TO PERHAPS -10F...WL ALSO ACCENTUATE
LAND BREEZE CNVGC. TENDED TO BUMP UP QPF OVER CONSENSUS FCST IN THIS
AREA...WHERE AN LES HEADLINE WL LIKELY BE NECESSARY. RIGHT NOW...
LOOKS LIKE WIND CHILLS WL NOT FALL TO ADVY CRITERIA /-25F/ AS WINDS
WL BE LIGHTER OVER THE INTERIOR W WHERE MIN TEMPS WL BE LOWEST.
ALTHOUGH H85 TEMPS WL BE A FEW DEGREES HIER ON MON THAN ON SUN...A
MORE W WIND COMPONENT THAT LIMITS LK SUP MODERATION SUGGESTS MAX
TEMPS WL BE NO WARMER AND PERHAPS EVEN COLDER ON MON THAN SUN. THIS
MORE BACKED FLOW WL KEEP MUCH OF THE CWA DRY TO THE S OF THE MORE
DOMINANT LES BAND THAT MAY IMPACT NRN ONTONAGON/CENTRAL HOUGHTON
COUNTY AND PERHAPS THE FAR E NEAR LK SUP.
MON NGT/TUE...MEDIUM RANGE GUIDANCE IS COMING INTO BETTER AGREEMENT
ON TIMING/TRACK OF CLIPPER TYPE SHRTWV FCST TO DIG OVER NRN MN BY
00Z TUE...OVER THE LOWER GREAT LKS AT 12Z TUE AND THEN OVER SE
ONTARIO LATE ON TUE. ALTHOUGH THE ACCOMPANYING SFC LO IS PROGGED TO
PASS TO THE S THRU WI AND LOWER MI...MODELS SHOW LLVL W FLOW ON MON
EVNG BECOMING SHARPLY CYC AND VEERING TO THE NNW ON TUE...WHICH IS
PROGGED TO ADVECT H85 TEMPS AS LO AS -22C TO -24C BACK OVER UPR MI
BY LATER ON TUE. SINCE THE DEEP LYR QVECTOR CNVGC IS PROGGED TO
IMPACT UPR MI TO THE N OF THE SHRTWV TRACK...GFS FCST SDNGS SHOW
DEEP MOISTENING DESPITE LACK OF MSTR INFLOW INTO THE AREA AHEAD OF
THE SHRTWV THAT WL LIMIT QPF AWAY FM LK SUP MOISTENING. BUT LOOKS
LIKE A HEADLINE LK ENHANCED EVENT MAY BE IN THE WORKS FOR LATE MON
NIGHT THRU MUCH OF TUE FOR THE FAVORED AREAS IMPACTED BY THE LES OFF
LK SUP. GUSTY WINDS AND INCRSGLY SMALL SN FLAKES ASSOCIATED WITH
DESCENDING DGZ MAY ALSO RESULT IN SOME VERY LO VSBYS.
EXTENDED...ON WED...WINDS WL BACK AGAIN TO A MORE W DIRECTION AS HI
PRES TRAILING THE DEPARTING CLIPPER SHRTWV SHIFTS FM THE NRN PLAINS
INTO THE OH RIVER VALLEY. WITH THE BACKING FLOW...THE PURE LES WL
BECOME MORE RESTRICTED TO THE KEWEENAW AND AREAS NEAR LK SUP FM
GRAND MARAIS TO WHITEFISH PT. SOME OF THE LONGER RANGE GUIDANCE
HINTS ANOTHER SHRTWV/SFC LO WL APRCH LATER WED/THU...WITH WAA BAND
OF SN ARRIVING TO THE N OF ASSOCIATED WARM FNT...FOLLOWED BY SOME
LES ON FRI AS A MORE MODERATELY COLD AIRMASS RETURNS. BUT EXPLICIT
MODELS SHOW CONSIDERABLE VARIABILITY DURING THIS LATE WEEK PERIOD...
SO DID NOT STRAY FM CONSENSUS FCST.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 644 AM EST SAT JAN 9 2016
COLD AIR MOVING INTO THE AREA TODAY WILL LEAD TO A PROLONGED PERIOD
OF LAKE EFFECT SNOW OVER UPPER MICHIGAN. THE LAKE EFFECT SNOW WILL
DEVELOP FROM WEST TO EAST THROUGH THE DAY...LEADING TO LOWERING
VISIBILITIES FROM MVFR TO IFR BY THIS AFTERNOON AND POSSIBLY
REACHING LIFR AT TIMES TONIGHT AT KCMX/KIWD. CEILINGS WILL REMAIN
FAIRLY STEADY IN THE BORDERLINE IFR/MVFR CATEGORY THIS MORNING
BEFORE SLOWLY RISING INTO THE MIDDLE OF THE MVFR RANGE TONIGHT.
MAY NEED TO ADD BLOWING SNOW FOR TONIGHT AS WINDS INCREASE...BUT
LATEST TRENDS IN THE MODELS HAVE WINDS LOWER THAN INITIALLY
EXPECTED.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 407 AM EST SAT JAN 9 2016
A BROAD SURFACE LOW OVER NORTHERN LAKE MICHIGAN WILL CONTINUE
NORTHEAST AND SLOWLY DISSIPATE TODAY WHILE A SECONDARY LOW TAKES
SHAPE IN THE SOUTHERN PLAINS. WINDS HAVE ALREADY SHIFTED TO THE
NORTHWEST OVER THE WESTERN HALF OF THE LAKE AND EXPECT THAT WIND
SHIFT TO SLIDE EAST ACROSS THE REST OF THE LAKE THROUGH THE MORNING
HOURS. AT THIS POINT...ONLY EXPECT WINDS UP TO 30KTS THROUGH THIS
EVENING...BUT AS THE SECONDARY LOW LIFTS NORTHEAST THROUGH THE
SOUTHEASTERN GREAT LAKES LATE TONIGHT AND SUNDAY MORNING...THE
GRADIENT BETWEEN THE LOW AND THE HIGH IN THE CENTRAL/NORTHERN
PLAINS WILL PRODUCE OCCASIONAL NORTHERLY GALES TO 35KTS OVER THE
EASTERN HALF OF LAKE SUPERIOR. WITH ONLY MARGINAL GALES
EXPECTED...WILL KEEP THE GALE WATCH IN PLACE AND ALLOW THE DAY
SHIFT ONE FINAL LOOK TO SEE IF THE MODELS CONTINUE TO TREND WINDS
DOWN. ALSO EXPECT A PERIOD OF FREEZING SPRAY AND MAY NEED A HEAVY
FREEZING SPRAY WARNING IF THE WINDS/WAVES STAY AT THE CURRENTLY
FORECASTED LEVELS. THE WINDS WILL QUICKLY DIMINISH SUNDAY NIGHT AS
THE LOW DEPARTS...BUT ANOTHER LOW WILL QUICKLY DROP SOUTHEAST ACROSS
THE UPPER GREAT LAKES MONDAY NIGHT AND BRING ANOTHER POTENTIAL FOR
NORTHERLY GALES TUESDAY INTO TUESDAY EVENING. BEHIND THE LOW...A
HIGH PRESSURE RIDGE WILL MOVE INTO THE AREA FOR WEDNESDAY AND
DIMINISH WINDS BELOW 25KTS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WATCH FROM LATE TONIGHT THROUGH LATE SUNDAY NIGHT FOR
LSZ249>251-266-267.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...KC
AVIATION...SRF
MARINE...SRF
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
959 PM CST SUN JAN 10 2016
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 210 PM CST SUN JAN 10 2016
TWO CONCERNS IN THE SHORT TERM. THE FIRST IS HOW COLD WILL IT BE
TONIGHT AND THE SECOND IS THE ONSET OF LIGHT SNOW MONDAY
AFTERNOON AS A CLIPPER MOVES SOUTHEAST ALONG THE ARCTIC FRONT.
AT MID AFTERNOON...A SURFACE RIDGE OF HIGH PRESSURE STRETCHED
NORTH-SOUTH ALONG THE DAKOTAS/MN BORDER. THIS FEATURE HAS MOVED
LITTLE TODAY DUE TO A LOW PRESSURE STORM SYSTEM MOVING NORTHWARD
ACROSS THE EASTERN GREAT LAKES. AS THE LOW ADVANCES NORTHWARD
TONIGHT...THE RIDGE AXIS WILL MOVE EASTWARD...EXTENDING ACROSS WI
MONDAY MORNING. THIS RAISES CONFIDENCE ON ANOTHER NIGHT OF LOW
TEMPERATURES FROM 15 TO 20 DEGREES BELOW ZERO IN WEST CENTRAL WI
AS WELL AS NORTH OF THE TWIN CITIES. FORTUNATELY...WIND SPEEDS
WILL BE UNDER 5 MPH MONDAY MORNING WITH WIND CHILL NUMBERS JUST A
TAD BELOW MINUS 25. LOWS WILL BE A LITTLE WARMER OVER WEST CENTRAL
THROUGH SOUTH CENTRAL MN (-8 TO -12) WITH A NON DIURNAL TREND LATE
IN THE NIGHT AS SOUTHERLY WINDS BEGIN TO INCREASE IN THESE AREAS.
MONDAY WILL START DRY...BUT CLOUDS WILL BE ON THE INCREASE EARLY
ON AS A WAVE OF LOW PRESSURE HEADS OUR WAY FROM SOUTHERN MANITOBA.
THE TIMING AND PRECIPITATION SIGNAL FROM THIS SYSTEM REMAIN
STRONG LEADING TO HIGH CONFIDENCE OF LIKELY POPS SPREADING INTO
CENTRAL MN EARLY IN THE AFTERNOON AND REACHING ACROSS THE TWIN
CITIES AND WESTERN WI BY LATE IN THE AFTERNOON. QPF AMOUNTS FOR
THE AFTERNOON REMAIN LIGHT (A FEW HUNDREDTHS). HOWEVER...WITH SNOW
RATIOS GREATER THAN 20:1...A HALF INCH OR SO OF SNOW IS LIKELY
ACROSS CENTRAL MN WITH A COUPLE OF TENTHS FOR THE TWIN CITIES AND
ADJOINING AREAS OF WEST CENTRAL WI. THIS COULD IMPACT THE EVENING
COMMUTE WITH SOME SLIPPERY ROAD CONDITIONS OCCURRING.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 210 PM CST SUN JAN 10 2016
THE LONG TERM FEATURES BELOW NORMAL TEMPERATURES AND MAINLY DRY
WEATHER THROUGH THE WEEK.
MODEL GUIDANCE HAS TRENDED A BIT COOLER WITH TEMPERATURES NEXT
WEEK...AND IT NOW APPEARS THE SLIGHT WARMING TREND LATE IN THE WEEK
WILL GIVE WAY TO ANOTHER ARCTIC COLD FRONT FOR THE WEEKEND. TUESDAY
MORNING...WEDNESDAY MORNING...SATURDAY MORNING AND SUNDAY MORNING
WILL ALL LIKELY FEATURE BELOW ZERO TEMPS...AND DOUBLE DIGIT BELOW
ZERO READINGS ARE POSSIBLE DEPENDING ON WHAT THE WINDS/CLOUDS ARE
DOING EACH OF THESE NIGHTS.
THE BEST CHANCE FOR LIGHT SNOW IN THE COMING DAYS BEGINS IN THE
SHORT TERM AND LASTS INTO MONDAY NIGHT. WE HAVE INCREASED POPS TO
70% OR GREATER GENERALLY NORTH OF THE I-94 CORRIDOR IN MN/WI MONDAY
EVENING...BUT LIGHT SNOW COULD CERTAINLY EXTEND SOUTH OF THE
INTERSTATE. THE SURFACE WAVE RESPONSIBLE FOR THE LIGHT SNOW DEEPENS
IN WI AND THE UPWARD VERTICAL MOTION INCREASES ACROSS THE EASTERN
FORECAST AREA MONDAY EVENING. THE ATMOSPHERE IS COLD AND WONT
CONTAIN A LOT OF MOISTURE...BUT WE SHOULD HAVE NO PROBLEM SATURATING
AND THE DENDRITE GROWTH ZONE EXTENDS ALL THE WAY TO THE GROUND. WE
ONLY EXPECT A TRACE TO MAYBE 0.03-0.04 INCH LIQUID...BUT WITH SNOW
RATIOS BETWEEN 20-30:1...1-2 INCHES OF SNOW IS POSSIBLE NORTH OF I-
94. THE TWIN CITIES METRO COULD PICK UP A DUSTING TO HALF INCH OF
FLUFF. THE WAVE MOVES THROUGH QUICKLY AS A SURFACE HIGH DROPS ACROSS
THE DAKOTAS. THE 850MB TEMPS COMING DOWN TUESDAY MORNING ARE
ACTUALLY 2-3C COLDER THAN WHAT IS COMING THROUGH TODAY.
THEREFORE...WE MAY ACTUALLY SEE TEMPS DROP OR AT THE VERY LEAST
REMAIN STEADY DURING THE DAY TUESDAY. WE MAY NEED A WIND CHILL
ADVISORY TUESDAY. CLOUDS WILL BE HIT OR MISS THROUGH WEDNESDAY. THE
GFS/NAM SOUNDINGS SHOW A LOT OF LOW LEVEL RH THROUGH WED/THU.
THURSDAY INTO EARLY FRIDAY WILL BE A BIT MILDER WITH THE RETURN
OF WEAK WEST/SOUTHWEST FLOW...BUT THERE IS ONLY ABOUT 36 HOURS
BETWEEN THE RETREATING COLD AIR WEDNESDAY NIGHT AND THE ARRIVAL OF
ANOTHER ARCTIC BOUNDARY FRIDAY AFTERNOON. THE ECMWF IS COLDER THAN
THE GFS WITH THE LATE WEEK COLD SNAP.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 959 PM CST SUN JAN 10 2016
MAIN ISSUE FOR THE FIRST 12 HOURS OR SO IS THE PATCHWORK OF MVFR
CEILINGS IN WEST CENTRAL...CENTRAL AND SOUTHWEST MN. THIS HAS
GENERALLY BEEN SLOWLY EXPANDING AND STREAMING TO THE SOUTHEAST.
MOST RECENT HI-RES MODELS SUGGEST THIS WILL PERSIST WELL INTO
MONDAY MORNING. WITH THE RIDGE SLIDING EAST...WARM ADVECTION INTO
MN SHOULD ALLOW THIS TO CONTINUE EXPANDING SLOWLY ACROSS
WESTERN/SOUTHERN MN. MOST LIKELY AREA TO AVOID THE STRATUS WILL
BE EAST CENTRAL MN INTO WISC...BUT EVEN HERE THERE MAY BE SOME
ISOLATED POCKETS OF ICE CRYSTALS AND SHALLOW IFR CEILINGS IN THE
ARCTIC AIR.
MONDAY AFTERNOON/EVENING...A WEAK CLIPPER LOW PRESSURE SYSTEM
WILL BRING AN INCREASING CHANCE OF LIGHT SNOW AND MVFR CONDITIONS
FOR 4-6 HOURS IN ANY GIVEN SPOT. THIS SNOW SHOULD BEGIN MID
AFTERNOON IN WEST CENTRAL MN AND QUICKLY SLIDE TO THE SOUTHEAST.
SOME VISIBILITIES MAY DROP TO 2SM...BUT WILL NOT BE SHOCKED IF
THERE ARE SOME AREAS OF 1SM IN THE SNOW FROM CENTRAL MN INTO WISC.
SHOULD ALSO MENTION THAT SW MN MAY ONLY GET A GLANCING BLOW.
KMSP...MVFR CEILINGS AROUND 1800 FT AGL EXPANDING/DEVELOPING TO
THE SOUTHEAST...AND MAY REACH KMSP SHORTLY AFTER 06Z. SHORT TERM
MODELS HAVE NOT BEEN HANDLING THIS WELL...BUT THE LATEST RAP DOES
GIVE SOME HINT THAT THE MVFR MAY PERSIST MUCH OF MONDAY MORNING.
GIVEN THE WARM ADVECTION PATTERN AND THE COLD ARCTIC AIR...SUSPECT
MVFR WILL INDEED HANG AROUND MUCH OF MONDAY MORNING. THEN THE
CLIPPER ARRIVES WITH LIGHT SNOW LATE MONDAY AFTERNOON FOLLOWED BY
INCREASING NORTHWEST WINDS LATER MONDAY NIGHT. HAVE INDICATED 2SM
VISIBILITY IN THE LIGHT SNOW. LOWER VISIBILITIES IN SNOW SHOULD BE
A LITTLE NORTH OF KMSP...BUT THIS WILL BE CLOSE.
/OUTLOOK FOR KMSP/
.TUE...VFR. WINDS NW 10-15 G25 KTS.
.WED...VFR. WINDS SW 5-10 KTS.
.THU...VFR. WINDS SW 5-10 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
&&
$$
SHORT TERM...RAH
LONG TERM...CLF
AVIATION...AJZ
AREA FORECAST DISCUSSION
NWS DULUTH MN
324 PM CST SAT JAN 9 2016
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 323 PM CST SAT JAN 9 2016
CONCERN FOR SHORT TERM IS SNOW SHOWERS ALONG SOUTH SHORE SNOW AND WIND
CHILLS/CLOUD COVER ACROSS REST OF FORECAST AREA.
CURRENT SURFACE ANALYSIS INDICATES FLURRIES/SNOW SHOWERS ACROSS
AREAS MAINLY EAST OF HIGHWAY 53. THERE ARE LOWER VISIBILITIES DUETO
HEAVIER SNOW SHOWERS ASX AND EAST ON HIGHWAY 2. THE FLURRIES/LIGHT
SNOW IS CAUSED BY AN UPPER LOW PRESSURE TROUGH MOVING THROUGH THE
FORECAST REGION. THIS FEATURE WILL CLEAR THE FORECAST REGION BY
THIS EVENING. DRIER AIR IS PUSHING IN FROM THE NORTHWEST THIS
AFTERNOON CLEARING THE SKIES WEST OF HIGHWAY 53. THIS CLEARING
TREND WILL CONTINUE INTO NORTHWEST WISCONSIN THIS EVENING WITH
THE ENTIRE REGION MAINLY CLEAR TO PARTLY CLOUDY BY LATE EVENING.
THE ONLY EXCEPTION WILL BE ALONG THE SOUTHSHORE WHERE LAKE EFFECT
SNOW SHOWERS WILL OCCUR.
THE LOWS WILL DROP DOWN FAR BELOW ZERO TONIGHT. AT DLH...IT WILL
BE THE SECOND LATEST DATE FOR THE FIRST RECORDED BELOW ZERO
TEMPERATURES DATING BACK TO 1870. THESE TEMPS WILL COMBINE WITH
NW WINDS OF 5 TO 15 MPH WILL CAUSE WIND CHILLS TO DROP TO THE -25
TO -30 RANGE. CURRENT WC ADVISORY LOOKS GOOD AND WILL NOT CHANGE
TIMING/COVERAGE.
THE RIDGE WILL DOMINATE THE WEATHER ACROSS THE FORECAST AREA ON
SUNDAY. SKIES WILL BE SUNNY TO PARTLY SUNNY EXCEPT FOR THE CLOUDS
ACROSS THE SOUTHSHORE WITH THE SNOW SHOWERS STILL CONTINUING.
ACCUMULATIONS IS STILL FORECAST TO BE IN THE 2-5 INCH RANGE
THROUGH SUNDAY EVENING. HIGH TEMPS AWAY FORM THE LAKE WILL BE IN
THE SINGLE FIGURES ABOVE AND BELOW ZERO.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 303 PM CST SAT JAN 9 2016
CLOSED LOW POSITIONED OVER HUDSON BAY WILL ALLOW FOR SEVERAL
SHORTWAVES TO ROTATE ACROSS THE REGION THE IN THE CYCLONIC FLOW. A
MODELS ARE IN GOOD AGREEMENT A VORT MAX DROPS OUT OF CANADA AND
SWEEPS OVER THE NORTHLAND MONDAY NIGHT THROUGH TUESDAY. HAVE
INCREASED POPS DURING THIS TIME AS LAPSE RATES BECOME FAVORABLE FOR
LIGHT SNOW SHOWERS. HOWEVER...AMOUNTS WILL BE LIGHT WITH GENERALLY
AROUND AND INCH ACROSS THE FORECAST AREA. FLURRIES TO A DUSTING OF
LIGHT SNOW WILL LINGER DURING THE DAY TUESDAY IN THE COLD AIR
ADVECTION REGIME WHERE 850HPA TEMPS HANG IN THE 25C RANGE. HAVE ALSO
INCREASED WINDS ABOVE SUPERBLEND GUIDANCE TO ACCOUNT FOR THE COLD AIR
ALOFT PRODUCING STEEP LOW LEVEL LAPSE RATES AND ADDITIONAL GUSTS
MONDAY NIGHT/TUESDAY.
ADDITIONAL SNOW SHOWERS ARE EXPECTED ALONG THE SOUTH SHORE OF LAKE
SUPERIOR THROUGH TUESDAY NIGHT...MAINLY OVER NORTHERN ASHLAND AND
IRON COUNTIES...WHERE WINDS AND TEMPS WILL BE FAVORABLE FOR LAKE
EFFECT/ENHANCED SNOW.
AN AREA OF CANADIAN HIGH PRESSURE BUILDS INTO THE DAKOTAS AND
WESTERN MINNESOTA TUESDAY...WITH THE RIDGE AXIS EXPECTED TO TRACK
OVER THE NORTHLAND DURING THE TUESDAY NIGHT/WEDNESDAY TIME FRAME.
DEPENDING ON TIMING AND ABILITY FOR SKIES TO CLEAR...OVERNIGHT LOW
TEMPS TUESDAY NIGHT INTO WEDNESDAY MORNING HAVE THE POTENTIAL TO
FALL INTO THE TEENS TO POSSIBLY AROUND 20 BELOW ZERO IN LOCATIONS
THAT CLEAR OUT AND WINDS DECOUPLE. WIND CHILL HEADLINES MAY BE
NEEDED.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1231 PM CST SAT JAN 9 2016
A TROUGH WILL MOVE THROUGH NORTHERN MINNESOTA AND INTO NORTHERN
WISCONSIN BY LATE TONIGHT. BEHIND THE TROUGH HIGH PRESSURE WILL
NUDGE ITS WAY INTO WESTERN WESTERN PORTIONS OF MINNESOTA. THIS
WILL RESULT IN MVFR CIGS UNTIL 20-00Z AT ALL TERMINALS EXCEPT FOR
KHYR WHERE MVFR CIGS WILL PERSIST THROUGH THE TAF CYCLE.
LIGHT SNOW AND FLURRIES ARE EXPECTED AT ALL SITES EXCEPT
KBRD...WHERE THE LATEST VIS SATELLITE SHOWS DRIER AIR ALREADY WORKING
ITS WAY INTO CENTRAL MINNESOTA. TRIED TO TIME THE ENDING OF SNOW
AT KDLH/KHIB/KINL BY THE LATEST OBS ALONG WITH THE RAP WHICH HAS
HAD BEST HANDLE ON THINGS. VISBY HAS DROPPED TO 1-5 SM WHERE
SNOWFALL IS OCCURRING...SO WILL SEE MUCH OF THE SAME BEFORE
20-00Z. AFTER THIS ALL SITES EXCEPT KHYR WILL BE VFR...WITH THE
MAIN CONCERN BEING SUSTAINED WINDS GREATER THAN 10 KTS OVERNIGHT
WITH SOME GUSTS.
KHYR WILL REMAIN MVFR THROUGH THE FORECAST WITH SOME IFR VISBY
REDUCTION FROM SNOW SHOWERS. UNSURE HOW WIDESPREAD SNOW SHOWERS
WILL BE AFTER 00Z AS DRIER AIR WORKS ITS WAY INTO THE REGION...SO
KEPT AT MVFR CIGS WITH VCSH.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH -11 1 -10 7 / 0 0 10 20
INL -16 -3 -15 2 / 0 0 0 30
BRD -16 3 -10 9 / 0 0 0 40
HYR -8 3 -14 6 / 20 10 10 10
ASX 0 5 -5 8 / 40 30 20 20
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
WI...WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 10 AM CST SUNDAY
FOR WIZ001-002-006>009.
MN...WIND CHILL ADVISORY FROM 6 PM THIS EVENING TO 10 AM CST SUNDAY
FOR MNZ010>012-018>021-025-026-033>038.
LS...SMALL CRAFT ADVISORY UNTIL 4 AM CST SUNDAY FOR LSZ121-140-141-
146>148.
&&
$$
SHORT TERM...STEWART
LONG TERM...GRANING
AVIATION...WL
AREA FORECAST DISCUSSION
NWS DULUTH MN
1231 PM CST SAT JAN 9 2016
.UPDATE...
ISSUED AT 1155 AM CST SAT JAN 9 2016
UPDATED TO ADD SCT SNOW SHOWERS TO THE TWIN
PORTS...NORTHSHORE...AND NW WI EXCEPT FOR THE SNOW BELT AREAS
WHERE LIKELY POPS ARE ALREADY THERE. THIS SNOW IS THE RESPONSE TO
A SHORT WAVE/UPPER LEVEL TROUGH MOVING THROUGH THE REGION. THE
SNOW WILL TAPER OFF THIS AFTERNOON AS DRIER AIR MOVES INTO THE
AREA.
UPDATE ISSUED AT 950 AM CST SAT JAN 9 2016
UPDATED TO EXPAND AREA OF FLURRIES ACROSS NE MN THROUGH MIDDAY.
OBSERVATIONS REPORT VISIBILITIES VARYING FROM 1.5 TO 5 MILES
ACROSS THE REGION. THIS SNOW IS IN RESPONSE TO A SHORT WAVE
MOVING ACROSS NORTHERN MN THIS MORNING. THERE IS CLEARING BEHIND
THE WAVE IN SOUTHERN CANADA BUT THAT WONT REACH THE WESTERN AREAS
UNTIL THIS AFTERNOON. ALSO INCREASED WINDS A FEW MPH ALONG THE
NORTHSHORE DUE TO OBSERVATIONS SHOW WINDS 15 TO 25 WITH GUSTS TO
NEAR 30 MPH. MODELS INDICATE THE WINDS WILL SLOW DECREASE THIS
AFTERNOON. ALSO ADJUSTED CLOUD COVER BASED ON TRENDS AND MODEL
FORECASTS. REST OF FCST UNCHANGED.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 415 AM CST SAT JAN 9 2016
THE FIRST TRUE ARCTIC AIR OUTBREAK OVER THE UPPER MIDWEST WILL
FINALLY OCCUR THIS WEEKEND AFTER A VERY MILD WINTER THUS FAR. TEMPS
WILL FALL TONIGHT TO VALUES NOT SEEN SINCE LAST WINTER...MARCH 5
2015 TO BE EXACT. THIS COLD WILL NOT JUST BE A RETURN TO NORMAL BUT
A BOOMERANG FROM WELL ABOVE NORMAL TO WELL BELOW NORMAL...WITH LOWS
TONIGHT FALLING TO AROUND 10 DEGREES BELOW NORMAL AND HIGHS SUNDAY
AROUND 15 DEGREES BELOW NORMAL. /THIS COMPARED HIGHS AND LOWS 13 TO
14 DEGREES ABOVE NORMAL YESTERDAY AT DLH AND INL./ PRECIPITATION
CHANCES WILL BE LIMITED TO THE SOUTH SHORE OF LAKE SUPERIOR WHERE
LAKE EFFECT SNOW SHOWERS WILL PERSIST THROUGH MOST OF THE WEEKEND
AND RESULT IN LIGHT BUT LONG-LASTING SNOW SHOWERS...ACCUMULATING 1
TO 5 INCHES ALONG FAVORED AREAS OF THE BAYFIELD PENINSULA AND
ESPECIALLY ACROSS THE GOGEBIC RANGE IN NORTHERN IRON/ASHLAND
COUNTIES.
ON THE SYNOPTIC SCALE A FAIRLY STRAIGHTFORWARD SET UP WITH AN UPPER
LOW OVER HUDSON BAY AND AN UPPER RIDGE OVER THE WEST COAST RESULTING
IN NORTHWEST FLOW OVER THE NORTHWEST TERRITORIES...CANADIAN
PRAIRIE...AND NORTHERN PLAINS/UPPER MISSISSIPPI VALLEY. THIS WILL
ALLOW A SERIES OF ARCTIC AIR MASSES TO MOVE ACROSS THE REGION. WHILE
THERE ARE STILL FORECAST CHALLENGES WHICH WILL DICTATE JUST HOW FAR
TEMPS WILL FALL...CONFIDENCE IS OVERALL VERY HIGH...THE COLD IS
COMING.
TODAY A MID-LEVEL TROUGH AXIS ASSOCIATED WITH THE UPPER LOW OVER
HUDSON BAY WILL MOVE EAST ACROSS EASTERN NORTH DAKOTA AND NORTHERN
MINNESOTA AHEAD OF THE FIRST ROUND OF ARCTIC AIR. AS THIS TROUGH
AXIS MOVES ACROSS THERE HAS BEEN ENOUGH PVA AND THE NECESSARY MID-
LEVEL MOISTURE TO SUPPORT SNOW SHOWERS/FLURRIES ACROSS NORTHEAST
MINNESOTA THIS MORNING...THROUGH AS DRIER AIR MOVES IN TOWARDS MID
MORNING TODAY THIS LIGHT PRECIP WILL COME TO AN END. A SFC HIGH
PRESSURE MOVES ACROSS THE MISSOURI RIVER VALLEY INTO THE CENTRAL
PLAINS TODAY INTO TONIGHT...WITH THE INCREASED PRESSURE GRADIENT
FROM THE DEPARTING LOW OVER THE UPPER GREAT LAKES RESULTING IN
BREEZY WINDS THIS MORNING...WINDS WILL GRADUALLY DIMINISH FROM WEST
TO EAST INTO TONIGHT.
THE BIGGEST FORECAST CHALLENGE IS THE CLOUD COVER LATE TODAY INTO
TONIGHT. AS THE HIGH PRESSURE BUILDS TO THE WEST CLOUDS SHOULD CLEAR
OUT SAVE FOR SOME MID-LEVEL CLOUDS THAT MOVE ACROSS THE BORDERLAND
TONIGHT INTO SUNDAY MORNING ASSOCIATED WITH THE AFOREMENTIONED MID-
LEVEL TROUGH AXIS. WHILE MOST GUIDANCE IS INDICATING CLEAR SKIES AT
FIRST GLANCE...LOOKING AT MODEL SOUNDINGS THERE IS ENOUGH MOISTURE
IN PROFILES TO INDICATE THAT STRATUS MAY PERSIST INTO TONIGHT OR IF
IT DOES CLEAR...REDEVELOP TOWARDS SUNDAY MORNING IN NORTH CENTRAL
MINNESOTA. NAM MOS HINTS TOWARDS THIS WHILE GFS MOST REMAINS
OPTIMISTIC ON A CLEAR...AND THUS VERY COLD...NIGHT. FOR THE LOW
TEMPS TONIGHT STARTED WITH A BLEND OF GUIDANCE BUT THEN USED OUR
CLOUD COVER AND WIND SPEED FORECASTS TO DRILL DOWN ON WHERE TEMPS
MAY FALL THE FURTHEST...BLENDING TOWARDS OUR INTERNAL ECMWF MOS
WHERE CLOUDS CLEAR AND WINDS MAY GO CALM FOR A TIME. /THE ECMWF AND
ITS MOS HAS BEEN VERY PERSISTENT IN COLD TEMPS...ESPECIALLY ACROSS
THE BORDERLAND WITH SEVERAL PAST RUNS HAVING LOWS TO 25 BELOW OR
COLDER./ ALSO DROPPED TEMPS ANOTHER DEGREE OR TWO IN THE
TRADITIONALLY COLDEST AREAS PER LOCAL RESEARCH.
IN THE END WENT WITH A SOLUTION SLIGHTLY COLDER THAN THE PREVIOUS
FORECAST BUT NOT BY MUCH. HIGHS TODAY NEAR ZERO FROM WALKER TO THE
BORDERLAND...SINGLE DIGITS ELSEWHERE IN NORTHEAST MINNESOTA INTO THE
TEENS IN NORTHWEST WISCONSIN. LOWS 10 TO 25 BELOW ZERO TONIGHT IN
NORTHEAST MINNESOTA...NEAR ZERO TO 10 BELOW ZERO IN NORTHWEST
WISCONSIN. AND ON SUNDAY AS THE COLDEST AIR DRIFTS EAST AS A WEAK
LOW DEVELOPS ACROSS THE NORTHERN PLAINS HIGHS WILL BE LIMITED TO
NEAR ZERO TO THE MID SINGLE DIGITS...COLDEST NORTH OF HIGHWAY 2 IN
NORTHEAST MINNESOTA.
BESIDES THAN THE COLD TEMPS AND RESULTING WIND CHILLS LAKE EFFECT
SNOW SHOWERS WILL BE A PERSISTENT FEATURE THROUGH MUCH OF THE
WEEKEND. ALONG THE SOUTH SHORE OF LAKE SUPERIOR ANYWHERE BETWEEN AN
INCH AND 5 INCHES WILL FALL ACROSS THE WEEKEND. SNOW SHOWERS THIS
MORNING MAY DIMINISH FOR A TIME AS LOW LEVEL WINDS TURN MORE
WESTERLY AHEAD OF THE MID-LEVEL TROUGH AXIS APPROACHING FROM THE
WEST...BUT AS THE TROUGH GETS CLOSER TO THE SOUTH SHORE LOW LEVEL
WINDS TURN NORTH-NORTHWESTERLY AND LAKE EFFECT SNOW SHOWERS WILL
RAMP UP. THIS IS EXPECTED TO OCCUR THIS EVENING AND WILL COINCIDE
WITH WHEN THE COLDEST AIR WILL BE OVER THE LAKE...850MB TEMPS -20 TO
-24C WITH FAVORABLE WIND DIRECTION FOR BOTH THE BAYFIELD PENINSULA
AND ESPECIALLY THE GOGEBIC RANGE. ANY MID-LEVEL MOISTURE ASSOCIATED
WITH THE TROUGH WILL ONLY AID IN SNOW SHOWER DEVELOPMENT. WITH THE
SNOWFALL OCCURRING OVER A LONG PERIOD OF TIME DO NOT ANTICIPATE ANY
KIND OF ADVISORY WILL BE NECESSARY FOR THIS SNOWFALL.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 415 AM CST SAT JAN 9 2016
THE EXTENDED PERIOD WILL BE DOMINATED BY CANADIAN LOW PRESSURE OVER
HUDSON BAY STRETCHING DOWN INTO THE NORTHLAND. IN ADDITION TO A
STRONG AND COLD NORTHERLY FLOW...THIS LOW WILL BRING A SUCCESSION OF
SHORTWAVES THROUGH THE REGION. ONE WILL BE HEADING THROUGH THE
REGION MONDAY AFTERNOON AND EVENING WITH ANOTHER ONE QUICKLY
FOLLOWING MONDAY NIGHT AND TUESDAY. A FEW MORE WEAKER ONES WILL
FOLLOW LATER IN THE WEEK...BUT CONFIDENCE ON WHERE AND EXACTLY
WHEN IS DIFFICULT WITH THIS SYSTEM AS THE GFS BRINGS A CLOSED LOW
OVER THE REGION LATE IN THE WEEK WHILE THE ECMWF IS MUCH MORE
PROGRESSIVE WITH THE UPPER LOW AND SWINGS IT INTO NEWFOUNDLAND BY
THE END OF THE WEEK...BUT STILL BRINGS SOME ENERGY THROUGH THE
REGION.
IN GENERAL THE COLD TREND WILL CONTINUE WITH SOME MINOR WARM UPS
FOLLOWED BY MORE COLD. THE FIRST SLIGHT WARM UP WILL BE SUNDAY NIGHT
AS A SHOT OF WARM AIR ADVECTION OCCURS IN THE RETURN FLOW AS HIGH
PRESSURE SLIDES EAST AND LOW PRESSURE ADVANCES FROM THE WEST. SUNDAY
NIGHT TEMPS WILL DROP QUICKLY...BUT THEN WILL REMAIN FAIRLY STEADY
OR SLIGHTLY RISE OVERNIGHT. ONCE THIS LOW PASSES THROUGH MONDAY
THERE WILL BE ANOTHER SHOT OF VERY COLD AIR ARRIVING ON BRISK
NORTHWEST WINDS FOR TUESDAY. THIS LOW WILL BE A QUICK MOVING AND
FAIRLY DRY LOW AS IT MOVES ACROSS IOWA AND SOUTHERN WISCONSIN.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1231 PM CST SAT JAN 9 2016
A TROUGH WILL MOVE THROUGH NORTHERN MINNESOTA AND INTO NORTHERN
WISCONSIN BY LATE TONIGHT. BEHIND THE TROUGH HIGH PRESSURE WILL
NUDGE ITS WAY INTO WESTERN WESTERN PORTIONS OF MINNESOTA. THIS
WILL RESULT IN MVFR CIGS UNTIL 20-00Z AT ALL TERMINALS EXCEPT FOR
KHYR WHERE MVFR CIGS WILL PERSIST THROUGH THE TAF CYCLE.
LIGHT SNOW AND FLURRIES ARE EXPECTED AT ALL SITES EXCEPT
KBRD...WHERE THE LATEST VIS SATELLITE SHOWS DRIER AIR ALREADY WORKING
ITS WAY INTO CENTRAL MINNESOTA. TRIED TO TIME THE ENDING OF SNOW
AT KDLH/KHIB/KINL BY THE LATEST OBS ALONG WITH THE RAP WHICH HAS
HAD BEST HANDLE ON THINGS. VISBY HAS DROPPED TO 1-5 SM WHERE
SNOWFALL IS OCCURRING...SO WILL SEE MUCH OF THE SAME BEFORE
20-00Z. AFTER THIS ALL SITES EXCEPT KHYR WILL BE VFR...WITH THE
MAIN CONCERN BEING SUSTAINED WINDS GREATER THAN 10 KTS OVERNIGHT
WITH SOME GUSTS.
KHYR WILL REMAIN MVFR THROUGH THE FORECAST WITH SOME IFR VISBY
REDUCTION FROM SNOW SHOWERS. UNSURE HOW WIDESPREAD SNOW SHOWERS
WILL BE AFTER 00Z AS DRIER AIR WORKS ITS WAY INTO THE REGION...SO
KEPT AT MVFR CIGS WITH VCSH.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 7 -11 2 -10 / 20 0 0 0
INL -1 -16 -1 -15 / 10 0 0 0
BRD 4 -16 4 -10 / 0 0 0 10
HYR 13 -8 3 -14 / 20 20 10 10
ASX 18 0 6 -5 / 40 40 30 30
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
WI...WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 10 AM CST SUNDAY
FOR WIZ001-002-006>009.
MN...WIND CHILL ADVISORY FROM 6 PM THIS EVENING TO 10 AM CST SUNDAY
FOR MNZ010>012-018>021-025-026-033>038.
LS...SMALL CRAFT ADVISORY UNTIL 4 AM CST SUNDAY FOR LSZ121-140-141-
146>148.
&&
$$
UPDATE...STEWART
SHORT TERM...JJM
LONG TERM...CLC
AVIATION...WL
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1258 AM EST SAT JAN 9 2016
.SYNOPSIS...
A WEAK FRONT WILL LIFT NORTHWARD THROUGH THE REGION TONIGHT AND
BRING A BRIEF PERIOD OF SNOW SLEET AND FREEZING RAIN. A SECOND
SYSTEM WILL MOVE IN FROM THE SOUTH SATURDAY NIGHT AND SUNDAY WITH
WIDESPREAD RAIN EXPECTED THROUGH SUNDAY AFTERNOON. AS THIS SYSTEM
EXITS A COLD AIR MASS WILL PUSH IN FROM THE NORTHWEST AND CHANGE
THE LINGERING RAIN OVER TO SNOW. A PERSISTENT WEST WIND WILL ALLOW
FOR LAKE EFFECT SNOW SHOWERS THROUGH MOST OF THE WEEK ACROSS THE
FINGER LAKES AND INTO THE TUG HILL PLATEAU. SIGNIFICANT SNOW
ACCUMULATIONS ARE POSSIBLE.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
855 PM UPDATE...
TWO POSITIVE SIGNS: TEMPERATURES ARE NOT FALLING AS QUICKLY AS
FEARED, AND THE RADAR PICTURE IS MORE SPARSE THAN EXPECTED. FOR
THIS REASON, WE BELIEVE LIGHT FREEZING RAIN WILL BE ISOLATED.
WE RAISED TEMPERATURES THROUGH THE NEXT 3-6 HOURS AND CUT BACK ON
THE POPS, MOVING MORE IN LINE WITH THE HRRR AND NAM12 RADAR PROGS.
350 PM UPDATE... A WINTER WEATHER ADVISORY FOR FREEZING RAIN IS
IN EFFECT TONIGHT FOR PORTIONS OF CENTRAL NEW YORK AND NORTHEAST
PENNSYLVANIA.
A WEAK WARM FRONT CURRENTLY MOVING NEWD THROUGH OH/WV/VA THIS
AFTERNOON WILL SPREAD A NARROW BAND OF PRECIPITATION THROUGH THE
REGION TONIGHT. A LAYER OF MID LVL WAA COMBINED WITH A WEAK UPPER
S/W WILL TRIGGER AN INITIAL BAND OF PRECIP EARLY THIS EVENING. THE
SIGNIFICANT FACTOR WILL BE THE PRESENCE OF A WEDGE OF AIR BELOW
FREEZING NEAR THE SURFACE. A COLD AREA OF HIGH PRESSURE OVER ERN
QUEBEC EXTENDING SWD INTO NEW ENGLAND AND NOSING WWD INTO THE NRN
APPALACHIAN MTNS WILL KEEP A COLD AIR MASS IN PLACE AS THE WARM
AIR RIDES OVER THE TOP AND CREATES FAVORABLE THERMAL PROFILES FOR
FREEZING RAIN. ONE AREA OF CONCERN WILL BE THE NRN EDGE OF THE
ALLEGHENY MTNS IN THE HIGHER TERRAIN OF BRADFORD AND WYOMING
COUNTIES MAINLY THIS EVENING AND INTO THE EARLY OVERNIGHT. THE
SECOND AREA OF CONCERN WILL BE LOCATIONS EAST OF I-81 FROM THE SRN
TUG HILL PLATEAU INTO THE POCONO MTNS WHERE THE COLDEST SFC TEMPS
WILL BE LOCATED. THE FREEZING RAIN/DRIZZLE MAIN END UP LINGERING A
BIT LONGER AS THE BAND OF PRECIP EXITS TO THE E/NE SAT MORNING.
ICE ACCUMULATIONS WILL GENERALLY BE LESS THAN A TENTH OF AN
INCH...ALONG WITH LIGHT SNOW AMTS MIXED IN AT TIMES AS WELL. AREA
ROADS THAT ARE NOT TREATED MAY BECOME SLIPPERY TONIGHT AND
SATURDAY MORNING.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH SUNDAY NIGHT/...
350 PM UPDATE... A WEAK RIDGE IS EXPECTED TO BUILD IN BEHIND THE
DEPARTING WARM FRONT/ UPPER TROUGH THROUGH THE DAY SATURDAY WITH
LINGERING LIGHT RAIN AND/OR DRIZZLE INTO SATURDAY NIGHT. A MUCH
MORE DYNAMIC STORM SYSTEM WILL LIFT NEWD FROM THE OHIO VALLEY INTO
THE WRN GREAT LAKES DURING THE DAY SUNDAY. A RELATIVELY STRONG
PUSH OF MOISTURE FROM THE SOUTH WILL BECOME ENTRAINED INTO THE
SYSTEM AND PRODUCE MODERATE PERSISTENT RAIN ACROSS THE REGION
THROUGH SUNDAY AFTERNOON. PWAT VALUES AROUND 0.8 INCH WITH THIS
SYSTEM WILL ALLOW FOR A HALF INCH TO 1.5 INCHES OF RAINFALL ON
SUNDAY. RAINFALL AMOUNTS SHOULD NOT BE SIGNIFICANT ENOUGH FOR
HYDRO ISSUES.
A STRONG PUSH OF COLD AIR WILL DEVELOP ON THE BACK SIDE OF THE
SYSTEM BEHIND THE COLD FRONT SUNDAY NIGHT AND ALLOW THE RAIN TO
MIX WITH INITIALLY AND EVENTUALLY CHANGE OVER TO ALL SNOW.
SNOWFALL AMOUNTS WILL NOT ADD UP TO MUCH AS THE AIR MASS BEHIND
THE FRONT IS EXPECTED TO BE RELATIVELY DRY. THIS ARCTIC AIR MASS
WILL BE FAVORABLE FOR LAKE EFFECT SNOW...AND THE TRAJECTORIES FROM
THE WEST WILL ALLOW FOR LES BANDS TO SET UP EAST OF LAKE ERIE AND
EAST OF ONTARIO...POSSIBLY IMPACTING STEUBEN COUNTY WITH LIGHT
SNOW AND THE SRN TUG HILL PLATEAU WITH EVEN MORE SNOW.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
350 PM UPDATE... THE COLD ARCTIC PATTERN WILL REMAIN IN PLACE
THROUGH MOST OF THE WEEK WITH 850MB TEMPS AROUND -15 TO -20 DEG C
BLOWING ACROSS RELATIVELY WARM LAKES OF ERIE AND ONTARIO. THE
DETERMINING FACTOR FOR WHERE THE HEAVIEST SNOW WILL SET UP WILL BE
THE RESULTING WIND FIELD. A WESTERLY WIND WILL KEEP THE BEST
CHANCE OF ACCUMULATING LES OVER NRN ONEIDA COUNTY MONDAY AND
TUESDAY...BUT SHIFT THE BAND TO THE NORTH TUE NIGHT AS THE NEXT
WEAK CLIPPER SYSTEM MOVES IN FROM THE WEST AND BACKS THE WINDS TO
THE SSW. THIS COLD S/W WILL TRIGGER ADDITIONAL MORE WIDESPREAD
SNOW SHOWERS LATE TUE INTO WED...BUT AMOUNTS WILL BE LIGHT AS THE
AIR MASS IS EXPECTED TO BE VERY DRY. THE COLD AIR ALOFT WILL
INDUCE THE STEEP LOW LEVEL LAPSE RATES AND BE THE MAIN DRIVING
FORCE FOR THE SNOW PRODUCTION.
AS THE SYSTEM EXITS EAST...WINDS WILL VEER TO THE NW LATE
WEDNESDAY AND COMBINE WITH ANOTHER PUSH OF ARCTIC AIR TO PRODUCE
ADDITIONAL LAKE EFFECT SNOW INTO WED NIGHT. THE PATTERN REPEATS
THURSDAY INTO FRIDAY WITH THE PASSAGE OF ANOTHER S/W AND
ADDITIONAL LIGHT ACCUMULATING SNOW SHOWERS.
TEMPERATURES WILL REMAIN NEAR NORMAL MOST OF THE WEEK WITH HIGHS
IN THE MID TO UPPER 20S AND LOWS IN THE TEENS.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
A WARM FRONT WILL LIFT THROUGH THE AREA DURING THE EARLY MORNING
HOURS WITH SCT SHRA AND PATCHY DZ. CIGS HAVE ALREADY LOWERED TO
FUEL ALT KITH-KELM-KBGM...WHILE OTHER TERMINALS ARE TEETERING INTO
HIGH END MVFR BUT WILL EVENTUALLY ALSO ACHIEVE FUEL ALT. FOR
KBGM...MOIST UPSLOPE AND PATCHY DRIZZLE IN THE HOURS AROUND DAWN
SHOULD EVEN RESULT IN IFR AT TIMES...THOUGH FOR KITH DUE TO
DOWNSLOPING THAT WILL BE HARDER TO ACHIEVE UNTIL A WEAK WAVE
PASSES WITH ANOTHER BATCH OF LIGHT SHOWERS OR DRIZZLE TO ADD
MOISTURE THIS AFTERNOON /EVEN THEN IT WILL BE INTERMITTENT/. AS
MOISTENING CONTINUES...IFR CIG SHOULD BECOME PREDOMINANT FOR KBGM
LATE MORNING THROUGH AFTERNOON AND PROBABLY EVEN LOWERING FURTHER
THIS EVENING. IFR WILL ALSO EVENTUALLY BE REALIZED THIS EVENING
KAVP ONCE LOW LEVEL FLOW BACKS TO A RESTRICTION-FAVORABLE LIGHT
NORTHEASTERLY. GENERALLY SPEAKING HOWEVER...WIND FOR MOST
TERMINALS IF NOT LIGHT-VARIABLE WILL BE ESE-SSE 5-10 KTS...SEE
TAFS FOR SPECIFICS. ALSO...AT KRME- KSYR...BECAUSE OF LOCALIZED
TERRAIN-INDUCED ESE SURFACE WIND VERSUS A S-SSW LOW LEVEL JET
AROUND 40 KTS...THERE WILL BE A PERIOD OF MARGINAL LLWS EARLY THIS
MORNING.
WINDS E/SE 5-10 KNOTS.
.OUTLOOK...
SUN...RESTRICTIONS LIKELY FROM SOLID BATCH OF RAIN SHOWERS
ESPECIALLY EARLY MORNING TO MIDDAY. LINGERING RAIN SHOWERS MAY CHANGE
OVER TO SNOW SNOW SHOWERS WHILE DIMINISHING SUNDAY NIGHT.
MON/TUE/WED...VFR...BUT SPOTTY MVFR/IFR PSBL IN LAKE EFFECT SNOW
SHWRS OVER NY STATIONS.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...WINTER WEATHER ADVISORY UNTIL 7 AM EST THIS MORNING FOR PAZ039-
040-044-048-072.
WINTER WEATHER ADVISORY UNTIL 5 AM EST EARLY THIS MORNING FOR
PAZ038-043.
NY...WINTER WEATHER ADVISORY UNTIL 7 AM EST THIS MORNING FOR NYZ009-
036-037-045-046-056-057-062.
&&
$$
SYNOPSIS...BJT
NEAR TERM...BJT/DJP
SHORT TERM...BJT
LONG TERM...BJT
AVIATION...MDP
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
327 PM EST SAT JAN 9 2016
.SYNOPSIS...
A WARM FRONT WILL LIFT NORTH ACROSS THE AREA LATE IN THE DAY INTO
THIS EVENING. A STRONG COLD FRONT WILL SWEEP ACROSS THE AREA
EARLY SUNDAY MORNING. SHOWERS AND SOME THUNDERSTORMS WILL REMAIN
IN THE FORECAST UNTIL THE FRONT SWEEPS TO OUR EAST. A SECONDARY
COLD FRONT WILL MOVE ACROSS THE AREA TUESDAY NIGHT. TEMPERATURES
WILL BE BELOW NORMAL FOR MUCH OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1230 PM SATURDAY...I CERTAINLY DIDN`T LIE ABOUT THIS BEING A
COMPLEX FORECAST. LOW STRATUS CLOUDS HAVE THINNED ENOUGH TO LET
THE SUN BURN THROUGH THEM ACROSS THE BURGAW/WILMINGTON/SOUTHPORT
VICINITY AND WE ARE ALREADY AT FORECAST HIGHS AT NOON. I HAVE
TACKED ON ANOTHER DEGREE TO WILMINGTON FORECASTING 67 HERE, WITH
66 AND 65 AT BURGAW AND SOUTHPORT RESPECTIVELY.
SHOWERS CONTINUE TO ADVANCE TOWARD THE COAST AND MAY BEGIN ROLLING
ONSHORE NORTH OF CAPE FEAR IN THE NEXT 90 MINUTES. WHILE
TECHNICALLY CONVECTIVE THEY LOOK MORE LIKE WARM CLOUD/COALESCENCE
RAIN ON RADAR AND I EXPECT THEY`LL DUMP A TENTH TO A QUARTER INCH
ALONG THE CAPE FEAR COAST LATE THIS AFTERNOON INTO EARLY THIS
EVENING. PRECIP CHANCES FARTHER INLAND ARE LOOKING MUCH
POORER...AND I HAVE TRIMMED BACK POPS WITH EACH UPDATE WEST OF A
LINE FROM GEORGETOWN TO CONWAY TO LUMBERTON. WHERE WE CURRENTLY
STILL HAVE 50-70 POPS TONIGHT I MAY END UP TRIMMING THESE BACK
ANOTHER 20-30 PERCENT DEPENDING ON WHAT THE BAND OF PRECIP
ON/AHEAD OF THE COLD FRONT LOOKS LIKE IN A COUPLE HOURS. SEVERE
WEATHER IS LOOKING INCREASINGLY UNLIKELY AND I HAVE REMOVED
MENTION OF THIS FROM THE HAZARDOUS WEATHER OUTLOOK. DISCUSSION
FROM 930 AM FOLLOWS...
THIS IS A VERY COMPLEX FORECAST TODAY AND TONIGHT WITH PLENTY OF
OPPORTUNITY FOR ERROR. A WARM FRONT/COASTAL TROUGH NEAR THE
WESTERN EDGE OF THE GULF STREAM WILL WALK WESTWARD TOWARD THE
COAST...MOVING ONSHORE SOMETIME EARLY THIS EVENING. THE PRECISE
TIMING OF THE FRONTAL PASSAGE WILL HAVE ENORMOUS IMPACTS ON
TEMPERATURES TODAY.
WEST OF THE FRONT THERE IS A THIN BUT EXPANSIVE DECK OF LOW
STRATUS WITH PATCHIER CIRRUS ALOFT. VISIBLE SATELLITE, WEBCAMS,
AND A LOOK OUT THE WINDOW REVEALS THERE ARE SOME THIN SPOTS IN
THIS LOW STRATUS CURRENTLY. WITH VAD WIND PROFILES INDICATING EAST
AND SOUTHEAST WINDS DOWN AS LOW AS 1000 FEET AGL...IT WON`T TAKE
MUCH TO ERODE THE THIN LAYER OF NE WINDS AND "JUMP" THE FRONT
ONSHORE. FORECAST HIGHS RANGE FROM THE MID 60S IN THE WILMINGTON
AREA WITH LOWER 60S ALONG THE COAST WEST OF CAPE FEAR. HIGHS
SHOULD REACH THE UPPER 50S TO AROUND 60 INLAND. ALL OF THESE
TEMPERATURES WILL BE ACHIEVED VERY LATE IN THE DAY AS WARM
ADVECTION MAY BE MORE IMPORTANT THAN INSOLATION.
AS IS TYPICAL, MODELS PAINT A VARIETY OF FORECAST POSITIONS FOR
THE FRONT. THE 06Z NAM WAS THE FASTEST TO BRING THE FRONT IN,
WHILE THE 00Z ARW-NMM WAS THE SLOWEST. AN MEDIAN TIME WAS JUST
AFTER SUNSET ALONG THE EAST-FACING BEACHES OF CAPE FEAR, WITH
WINDS TURNING SOUTHERLY THROUGHOUT THE AREA INCLUDING FAR INLAND
DURING THE EVENING HOURS AS THE COLD FRONT OFF THE WEST BECOMES
THE PRIMARY FEATURE AFFECTING THE PRESSURE GRADIENT AND LOW-LEVEL
WINDS.
RADAR/SATELLITE IMAGES SHOWS WAVES OF SHOWERS DEVELOPING OVER THE
GULF STREAM MOVING NORTHWESTWARD. THE HRRR AND HRRRX MODELS BOTH
SHOW THESE IMPACTING THE COAST THIS AFTERNOON BEGINNING BETWEEN
2-4 PM. POPS HAVE BEEN INCREASED TO 50-80 PERCENT DURING THE
AFTERNOON HOURS. PRECIP CHANCES INLAND ARE LESS CERTAIN GIVEN MUCH
LESS ATLANTIC TRANSPORT OF MOISTURE THAT FAR WEST PLUS OVERALL
WEAK FORCING. MEASURABLE RAIN OVER THE INLAND PEE DEE REGION WILL
PROBABLY FOCUS MORE ON ANY PRECIP AHEAD OF THE COLD FRONT LATE
TONIGHT.
SEVERE WEATHER POTENTIAL APPEARS QUITE LIMITED GIVEN SURFACE-BASED
INSTABILITY REMAINING NEAR ZERO TODAY AND TONIGHT. ALTHOUGH
ELEVATED INSTABILITY MAY GROW TO 400-600 J/KG...FAIRLY WEAK UPPER
LEVEL SUPPORT AND THE PRESENCE OF A LARGE DRY SLOT ALOFT THIS
EVENING WILL TEND TO REMOVE CONVECTION DURING THE TIME WHEN THE
BEST WIND SHEAR WILL BE PRESENT. WHILE I CANNOT RULE OUT SEVERE
WEATHER COMPLETELY, THIS DOES NOT APPEAR TO BE A VERY CONCERNING
SETUP AT THIS TIME.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 300 AM SATURDAY...STRONG COLD FRONT COMES THROUGH TO START
THE PERIOD AND FOR A FEW DAYS NOW GETTING SUNDAY`S HIGH
TEMPERATURE SEEMS AWFULLY TRICKY AS IT WILL LIKELY BE IN THE
MORNING IF NOT PREDAWN. LINGERING COASTAL SHOWERS TO START THE
PERIOD, IF ANY, WILL QUICKLY SCOOT OFFSHORE IN THE STRONG COLD AND
DRY ADVECTION REGIME. 850 TEMPS PLUNGE TO ABOUT -2C SUNDAY NIGHT
BRINGING SOME SEASONABLE MID 30S AREA-WIDE. WITH NO REAL RECOVERY
IN LOW LEVEL THERMAL FIELDS ON MONDAY AFTERNOON HIGHS A SOLID
CATEGORY BELOW NORMAL WITH HIGHS IN THE MID TO UPPER 40S.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 300 AM SATURDAY...HIGH PRESSURE ON TUESDAY IS SUPPRESSED TO
OUR SOUTH AND WEST ON TUESDAY WITH THE APPROACH OF A STRONG UPPER
TROUGH AND MOISTURE-DEPRIVED COLD FRONT SLATED FOR A TUESDAY NIGHT
PASSAGE AFTER A SEASONABLE TO SLIGHTLY COOL TUESDAY TEMPERATURES
WILL TAKE A TURN DOWNWARD POSSIBLY FOR THE REMAINDER OF THE PERIOD
THOUGH MOST OF THE TIME CLOUD COVER WILL BE LOW END PARTLY CLOUDY
IF NOT LESS. THIS WILL CHANGE ON THURSDAY AS SOME MOISTURE STREAMS
IN ALOFT AHEAD OF A SOUTHERN BRANCH DISTURBANCE. THIS FEATURE MAY
BRING RAIN CHANCES ON FRIDAY.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
AS OF 18Z...CLEARING LINE WORKING WESTWARD FROM SOUTHEAST NC
SHOULD WORK THROUGH ALL COASTAL TERMINALS IN THE NEXT 2 TO 4
HOURS AND RESULT IN PREVAILING VFR CONDITIONS WITH TEMPO MVFR
CIGS DUE TO SHRA AND THE ASSOCIATED CIGS THIS AFTERNOON INTO
TONIGHT. INLAND TAF SITES LIKELY TO RETAIN IFR CIGS UNTIL WARM
FRONTAL PASSAGE IN THE 04Z TO 08Z WINDOW BUT SHOWERS
COULD RESULT IN MVFR CONDITIONS AFTER PREDOMINANT IFR LIFTS.
WINDS WILL SHIFT FROM NE TO E AT 5 TO 10 KT TO SE TO S AFTER
THE WARM FRONT LIFTS THROUGH. VFR CONDITIONS EXPECTED ALL
TERMINALS ON SW FLOW AFT 12Z THE 10TH.
EXTENDED OUTLOOK...EXPECT VFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1230 AM SATURDAY...FEW CHANGES ARE NEEDED WITH THIS NOON
UPDATE. LIGHT SHOWERS HAVE ALREADY MOVED INTO THE WATERS NORTH OF
CAPE FEAR AND WILL REACH THE REMAINDER OF THE WATERS SOUTH OF CAPE
FEAR BY LATE THIS AFTERNOON/EARLY THIS EVENING. WE ARE SEEING SOME
HEAVIER SHOWERS AND THUNDERSTORMS OUT OVER THE GULF STREAM...SOME
OF WHICH MAY MAKE IT INSIDE 20 MILES BY SUNSET. WINDS/SEAS ARE
IN-LINE WITH PREVIOUS FORECASTS. DISCUSSION FROM 930 AM FOLLOWS...
A WARM FRONT/COASTAL TROUGH NEAR THE WESTERN EDGE OF THE GULF
STREAM WILL MOVE WESTWARD TODAY, REACHING THE COAST OF CAPE FEAR
EARLY THIS EVENING. THE FRONT SHOULD THEN JUMP INLAND ALLOWING
WINDS TO BECOME SOUTHERLY ALONG THE SOUTH CAROLINA COAST TOO.
UNTIL THEN, NORTHERLY WINDS WILL CONTINUE ALONG THE COAST WITH
WIND SPEEDS UP TO 20 KNOTS AT TIMES IN A FAIRLY TIGHT PRESSURE
GRADIENT. THIS HAS BUILT SEAS UP TO 5 FEET NEAR AND NORTH OF CAPE
FEAR...AND AN EXERCISE CAUTION HEADLINE WILL REMAIN POSTED THERE
UNTIL 11 AM.
SHOWERS DEVELOPING OVER THE GULF STREAM ARE MOVING NORTHWESTWARD
AND SHOULD OVERSPREAD THE CAPE FEAR AREA AND MYRTLE BEACH WATERS
THIS AFTERNOON. ISOLATED THUNDERSTORMS ARE POSSIBLE TOO. AFTER A
LULL DURING THE EVENING HOURS, ANOTHER WAVE OF SHOWERS AND STORMS MAY
PUSH ACROSS THE AREA AHEAD OF THE COLD FRONT LATE TONIGHT.
SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 300 AM SATURDAY...A HEALTHY COLD FRONT WITH APPRECIABLE
DYNAMICS ALOFT CROSSES EARLY SUNDAY. WIND AND SEAS SHOULD READILY
RAMP UP TO ADVISORY LEVELS WHERE THEY WILL REMAIN MUCH OF SUNDAY
NIGHT AS WINDS VEER TO W AND THEN NW. LATER SUNDAY NIGHT INTO
MONDAY WILL FEATURE A CONSIDERABLE DECREASE IN BOTH WIND AND SEAS
AS HIGH PRESSURE BUILDS INTO THE GULF STATES AND A RIDGE AXIS
POKES INTO THE CAROLINAS AND MID ATLANTIC REGION EASING THE
GRADIENT ALONG MOST OF THE EAST COAST.
LONG TERM /TUESDAY THROUGH WEDNESDAY/...
AS OF 300 AM SATURDAY...A VERY LIGHT GRADIENT IN PLACE ON TUESDAY
AS THE POST-FRONTAL HIGH SINKS INTO THE GULF STATES AND WEAKENS
CONSIDERABLY. A MODERATELY STRONG COLD FRONT COMES THROUGH TUESDAY
NIGHT WITH GOOD DYNAMICS IN THE LOW TO MID LEVELS FOR SOME FAIRLY
STRONG WINDS THAT COULD YIELD SCEC FOR EITHER WIND OR SEAS. THIS
POST-FRONTAL HIGH WILL NOT BE SO QUICK TO WEAKEN NOR ENTER THE
AREA ON WEDNESDAY KEEPING THE GRADIENT A BIT TIGHTER BUT PROBABLY
NOT TO WHERE HEADLINES WILL BE NEEDED.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...MBB
NEAR TERM...TRA
SHORT TERM...MBB
LONG TERM...MBB
AVIATION...RAN
MARINE...
AREA FORECAST DISCUSSION
NWS RALEIGH NC
210 PM EST SAT JAN 09 2016
.SYNOPSIS... LOW PRESSURE WILL APPROACH THE AREA FROM THE WEST
TONIGHT. THE COLD FRONT WILL BLOW OFF THE COAST LATE TONIGHT AND
EARLY SUNDAY. COLD HIGH PRESSURE WILL ARRIVE FOR TONIGHT AND
MONDAY.
&&
.NEAR TERM /TODAY THROUGH TONIGHT/...
AS OF 240 AM SATURDAY...
THROUGH THIS MORNING... WIDESPREAD FOG AND THICK STRATUS ARE LIKELY
TO PERSIST WITHIN THE WEDGE REGIME... FEATURING A DAMMING SURFACE
HIGH CENTERED OFF THE CANADIAN MARITIMES NOSING SW INTO NC... CAPPED
BY WEAK BUT STEADY MOIST UPGLIDE. BLOCKED BY THE MOUNTAINS TO THE
WEST AND A FRONTAL ZONE WELL TO OUR SOUTH AND SE... THE WEDGE SHOULD
STAY LOCKED IN WELL INTO THE MORNING GIVEN THE STAGNANT SURFACE
AIR... PROFOUND CLOUD DEPTH... AND LACK OF ANY MECHANISM TO DISPERSE
IT IN THE VERTICAL. THE HRRR AND HRRR-X ARE STILL SHOWING INCREASING
FOG DENSITY THROUGH DAYBREAK... AND WHILE THIS IS FAR FROM CERTAIN
GIVEN THE EXTENT OF STRATUS... WILL KEEP A CLOSE EYE ON FOG
TRENDS... AND DENSE FOG ADVISORY MAY BE NEEDED THIS MORNING. THE
MOIST UPGLIDE DOESN`T APPEAR TO BE STRONG OR DEEP ENOUGH FOR
ANYTHING MORE THAN PATCHY DRIZZLE OVER THE NEXT SEVERAL HOURS... AND
OTHER FORCING MECHANISMS ARE LACKING AS WELL GIVEN THE DEPARTURE TO
OUR NE OF A BATCH OF MID LEVEL VORTICITY... SO POPS THROUGH THIS
MORNING WILL BE LOW. TEMPS WILL BE SLOW TO RISE THROUGH THE UPPER
40S AND LOW-MID 50S THIS MORNING.
MIDDAY TODAY THROUGH TONIGHT: THE ACTIVE SOUTHERN STREAM REACHES ITS
PEAK IMPACT ON THE SOUTHEAST STATES LATE THIS AFTERNOON AND TONIGHT
WITH PASSAGE OF A POTENT MID LEVEL SHORTWAVE TROUGH AND SURFACE LOW
TO OUR WEST AND NW... MOVING FROM THE LOWER MISS VALLEY NEAR MIDDAY
THROUGH THE TN AND ERN OH VALLEY THROUGH TONIGHT. WHILE THE CHANCE
OF EVERYONE SEEING AT LEAST SOME SHOWERS (AND PERHAPS A STORM OR
TWO... MORE ON THAT LATER) IS HIGH CONSIDERING THE PROJECTIONS OF
MUCH ABOVE NORMAL PW (0.90-1.20")... IT APPEARS THAT THE BULK OF THE
DYNAMIC FORCING FOR ASCENT WILL HOLD TO OUR WEST AND NORTH. THESE
MECHANISMS INCLUDES THE MID LEVEL DPVA WITH THE SHORTWAVE TROUGH AS
WELL AS THE STRONGEST UPPER DIVERGENCE WITH THE LEFT EXIT REGION OF
THE SUBTROPICAL JET... BOTH OF WHICH TAKE A PATH NW OF CENTRAL NC.
BUT THERE SHOULD STILL BE A STRONG INFLUX OF LOWER LEVEL MOISTURE...
FOCUSED INTO CENTRAL AND ERN NC OUT AHEAD OF A WEAK SURFACE LOW NOW
OVER SOUTH FLA AND EXPECTED TO TRACK NORTHWARD TODAY AND THROUGH
CENTRAL NC TONIGHT... DRAWING ENOUGH ATLANTIC MOISTURE INTO THE AREA
FOR A PERIOD OF CATEGORICAL POPS... FOCUSING LATE AFTERNOON THROUGH
TONIGHT... WITH GREATEST COVERAGE AND DURATION OCCURRING ACROSS THE
NRN AND ERN FORECAST AREA. AS THIS SURFACE LOW APPROACHES AND DRAWS
THE COASTAL WEDGE FRONT WESTWARD INTO THE NC COASTAL PLAIN THIS
EVENING/TONIGHT... WEAK INSTABILITY (PEAKING AT A MUCAPE OF ABOUT
500-1000 J/KG TONIGHT) ALONG WITH IMPRESSIVE DEEP LAYER SHEAR AOA 50
KTS COULD SUPPORT A FEW POCKETS OF STRONGER CONVECTION... MOST
LIKELY (ACCORDING TO THE LATEST MODEL RUNS) DURING THE EARLY TO MID
EVENING HOURS. IT`S UNCLEAR WHETHER OR NOT ANY WEAK INSTABILITY WILL
BE ACHIEVED DURING THE TIME OF GREATEST LOW LEVEL SHEAR (0-3 KM SRH
PREDICTED TO REACH 300-400 M2/S2 ON THE NAM AND ABOUT HALF THAT ON
THE GFS)... WHICH WOULD INFLUENCE THE THREAT OF SUPERCELLS. SUCH A
SCENARIO SEEMS UNLIKELY BUT THE POTENTIAL WILL BE MONITORED. IF
SURFACE DEWPOINTS OVER OUR EAST CLIMB INTO THE UPPER 50S TO AROUND
60 AS EXPECTED HOWEVER... WITH WINDS BECOMING MORE UNIDIRECTIONAL (A
STRAIGHTENING HODOGRAPH)... THERE COULD BE A RISK OF BOWING SEGMENTS
AND STRONG STRAIGHT LINE WINDS TONIGHT. WILL RESTRICT AN ISOLATED
MENTION OF THUNDER TONIGHT FROM RALEIGH EAST AND SOUTH... ALONG AND
EAST OF THE ANTICIPATED TRACK OF THE WEAK SURFACE LOW. THE
WARM/WEDGE FRONT WILL SHIFT BACK EAST OVER THE COASTAL PLAIN LATE
TONIGHT AS THE OCCLUDED FRONT APPROACHES. EXPECT HIGHS FROM THE
UPPER 40S TO NEAR 50 IN THE TRIAD TO NEAR 60 IN OUR FAR SE (CLINTON
TO GOLDSBORO). TEMPS SHOULD SLIP JUST A FEW DEGREES EARLY TONIGHT...
TO THE MID 40S NW TO MID-UPPER 50S SE... WITH STEADY TEMPS OR A
SLIGHT RISE OVERNIGHT. -GIH
&&
.SHORT TERM /SUNDAY THROUGH SUNDAY NIGHT/...
AS OF 245 AM SATURDAY...
CONSENSUS OF THE LATEST MODELS IS TO SHIFT THE FRONTAL ZONE AND
ATTENDANT PRECIP EAST OUT OF THE COASTAL PLAIN SUN MORNING... WITH
THE ONSET OF BRISK AND GUSTY SW WINDS... SHIFTING TO WESTERLY LATE
IN THE DAY... AS THE SECONDARY COLD FRONT (TRAILING THE POTENT
SURFACE LOW THAT WILL ACCOMPANY THE VORTICITY/UPPER DIVERGENCE MAX
UP THROUGH LAKE ERIE/LAKE ONTARIO) PUSHES EAST INTO THE AREA LATE.
LOW LEVEL THICKNESSES START TO DROP SUNDAY MORNING BUT WILL
INITIALLY BE OFFSET BY INCREASING SUNSHINE AND THE DELAY IN COLD AIR
ADVECTION. HIGHS SHOULD BE IN THE MID 50S TO LOWER 60S EARLY IN THE
DAY... WITH READINGS SLIPPING LATER IN THE DAY. WITH THE TIGHT MSLP
GRADIENT IN THE WAKE OF THE LAKE ERIE LOW... SUSTAINED WINDS OF 15-
20 KTS APPEAR LIKELY... WITH FREQUENT GUSTS TO AROUND 30 MPH... BOTH
LIGHTENING UP LATE IN THE DAY. MOSTLY CLEAR SUN NIGHT WITH
DIMINISHING WINDS AND WINDS BECOMING WNW AS COLDER AIR RUSHES IN.
LOWS 25-33. -GIH
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
AS OF 210 PM SATURDAY...
IT APPEARS THAT A RELATIVELY DRY AND CHILLY PATTERN WILL PREVAIL
THIS WEEK. THE EXCEPTION MAY BE TOWARD THE END OF THE WEEK WHEN
UNCERTAINTY INCREASES SIGNIFICANTLY WITH THE MODELS.
THERE IS HIGH CONFIDENCE EARLY IN THE WEEK WITH HIGH PRESSURE
EXPECTED TO BRING SUNNY AND COLDER TEMPERATURES MONDAY. HIGHS
GENERALLY SHOULD BE A FEW DEGREES BELOW THE 30 YEAR NORMS. EXPECT
MOSTLY MID TO UPPER 40S.
TUESDAY AND WEDNESDAY... AN ARCTIC COLD FRONT WILL SURGE THROUGH THE
REGION TUESDAY AFTERNOON. A PERIOD OF MID AND HIGH CLOUDINESS CAN BE
EXPECTED MONDAY NIGHT INTO TUESDAY ASSOCIATED WITH THE MID/UPPER
TROUGH APPROACH AND COLD FRONTAL PASSAGE. THE PREDOMINATE W-NW FLOW
WILL KEEP ANY QPF OUT OF THE FORECAST EAST OF THE MOUNTAINS.
HIGHS TUESDAY SHOULD MODERATE BEFORE THE TRUE CAA ARRIVES LATE IN
THE DAY AND TUESDAY EVENING WHEN NW WINDS 10-20 MPH WITH GUSTS TO 30
MPH CAN BE EXPECTED. HIGHS GENERALLY 48-53 TUESDAY WITH FALLING
TEMPERATURES IN THE AFTERNOON INTO THE NW PIEDMONT. MUCH COLDER
TEMPERATURES WITH DIMINISHING WINDS WITH CLEAR SKIES ARE EXPECTED
TUESDAY NIGHT WITH LOWS 20-25. WEDNESDAY... SUNNY AND COLD WITH
HIGHS ONLY 37-42. LOWS WEDNESDAY NIGHT 18-25.
THURSDAY THROUGH SATURDAY... PLENTY OF DIFFERENCES IN THE MODELS
HANDLING THE SPLIT FLOW PATTERN WITH THE ACTIVE SOUTHERN STREAM AND
POTENTIAL INTERACTION WITH THE POLAR JET. ENSEMBLES SUGGEST A MORE
ACTIVE SUBTROPICAL JET WITH ENERGY TRACKING FROM THE PACIFIC INTO
THE SOUTHWEST STATES... THEN POSSIBLY INDUCING A SYSTEM ALONG THE
GULF COAST STATES LATE IN THE PERIOD. OPERATIONAL MODELS ARE ALL
OVER THE PLACE WITH A POTENTIAL SYSTEM. FOR NOW... WE WILL MAINTAIN
THE CURRENT FORECAST OF NEAR AVERAGE TEMPERATURES AND AN INCREASE IN
CLOUDINESS FRI-SAT. LOWS GENERALLY 25-30 AND HIGHS 45-50. OBVIOUSLY
THIS WILL CHANGE IF/WHEN A SYSTEM DOES DEVELOP AS FAR AS TEMPS AND
POP.
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
AS OF 610 AM SATURDAY...
HIGH CONFIDENCE IN ADVERSE AVIATION CONDITIONS TONIGHT THROUGH MUCH
OF THIS MORNING... WITH ONLY SLOW IMPROVEMENT THEREAFTER. A WEDGE OF
COOL HIGH PRESSURE WILL CONTINUE TO NOSE IN FROM THE NE AT THE
SURFACE... WHILE DEEP MOISTURE STREAMS INTO THE AREA JUST OFF THE
SURFACE. THIS WILL KEEP DEEP LOW IFR/LIFR CLOUDS OVER THE REGION
WITH WIDESPREAD IFR/LIFR FOG. THE STAGNANT AIR MASS AND CLOUD DEPTH
WILL KEEP THESE ADVERSE CONDITIONS LOCKED IN LONGER THAN USUAL THIS
MORNING... AS IT MAY BE THE NOON HOUR OR EARLY AFTERNOON BEFORE WE
ACHIEVE MVFR CONDITIONS AT CENTRAL NC AIRFIELDS. AN APPROACHING
STORM SYSTEM FROM THE SOUTH AND SW WILL THEN BRING INCREASING CHANCE
FOR SHOWERS AND ISOLATED STORMS STARTING MID-LATE THIS AFTERNOON AND
LASTING THROUGH TONIGHT... WITH CONDITIONS AGAIN DETERIORATING TO
IFR BY THIS EVENING. AVIATION INTERESTS SHOULD BE ALERT FOR STRONG
WINDS FROM THE SE AT 1500-3000 FT AGL PRECEDING THE FRONT TONIGHT.
THESE STRONG WINDS FROM THE SE JUST OFF THE GROUND WILL CONTINUE TO
INCREASE AND VEER TO SOUTHWESTERLY LATE TONIGHT INTO SUN MORNING.
LOOKING BEYOND 12Z SUN MORNING... POOR AVIATION CONDITIONS WILL
PERSIST UNTIL PASSAGE OF A COLD FRONT FROM WEST TO EAST EARLY SUN
MORNING. CLEARING SKIES AND A TREND TO VFR ARE EXPECTED SUNDAY...
ALTHOUGH STRONG GUSTY WINDS FROM THE WEST ARE LIKELY POST-FRONT. VFR
CONDITIONS ARE EXPECTED TO DOMINATE THROUGH WED... ALTHOUGH GUSTY
WINDS MAY RETURN WITH A DRY COLD FRONT PASSAGE TUE NIGHT/WED. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...HARTFIELD
SHORT TERM...HARTFIELD
LONG TERM...BADGETT
AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1226 PM EST SAT JAN 9 2016
.SYNOPSIS...
A WARM FRONT WILL LIFT NORTH ACROSS THE AREA LATE IN THE DAY INTO
THIS EVENING. A STRONG COLD FRONT WILL SWEEP ACROSS THE AREA
EARLY SUNDAY MORNING. SHOWERS AND SOME THUNDERSTORMS WILL REMAIN
IN THE FORECAST UNTIL THE FRONT SWEEPS TO OUR EAST. A SECONDARY
COLD FRONT WILL MOVE ACROSS THE AREA TUESDAY NIGHT. TEMPERATURES
WILL BE BELOW NORMAL FOR MUCH OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1230 PM SATURDAY...I CERTAINLY DIDN`T LIE ABOUT THIS BEING A
COMPLEX FORECAST. LOW STRATUS CLOUDS HAVE THINNED ENOUGH TO LET
THE SUN BURN THROUGH THEM ACROSS THE BURGAW/WILMINGTON/SOUTHPORT
VICINITY AND WE ARE ALREADY AT FORECAST HIGHS AT NOON. I HAVE
TACKED ON ANOTHER DEGREE TO WILMINGTON FORECASTING 67 HERE, WITH
66 AND 65 AT BURGAW AND SOUTHPORT RESPECTIVELY.
SHOWERS CONTINUE TO ADVANCE TOWARD THE COAST AND MAY BEGIN ROLLING
ONSHORE NORTH OF CAPE FEAR IN THE NEXT 90 MINUTES. WHILE
TECHNICALLY CONVECTIVE THEY LOOK MORE LIKE WARM CLOUD/COALESCENCE
RAIN ON RADAR AND I EXPECT THEY`LL DUMP A TENTH TO A QUARTER INCH
ALONG THE CAPE FEAR COAST LATE THIS AFTERNOON INTO EARLY THIS
EVENING. PRECIP CHANCES FARTHER INLAND ARE LOOKING MUCH
POORER...AND I HAVE TRIMMED BACK POPS WITH EACH UPDATE WEST OF A
LINE FROM GEORGETOWN TO CONWAY TO LUMBERTON. WHERE WE CURRENTLY
STILL HAVE 50-70 POPS TONIGHT I MAY END UP TRIMMING THESE BACK
ANOTHER 20-30 PERCENT DEPENDING ON WHAT THE BAND OF PRECIP
ON/AHEAD OF THE COLD FRONT LOOKS LIKE IN A COUPLE HOURS. SEVERE
WEATHER IS LOOKING INCREASINGLY UNLIKELY AND I HAVE REMOVED
MENTION OF THIS FROM THE HAZARDOUS WEATHER OUTLOOK. DISCUSSION
FROM 930 AM FOLLOWS...
THIS IS A VERY COMPLEX FORECAST TODAY AND TONIGHT WITH PLENTY OF
OPPORTUNITY FOR ERROR. A WARM FRONT/COASTAL TROUGH NEAR THE
WESTERN EDGE OF THE GULF STREAM WILL WALK WESTWARD TOWARD THE
COAST...MOVING ONSHORE SOMETIME EARLY THIS EVENING. THE PRECISE
TIMING OF THE FRONTAL PASSAGE WILL HAVE ENORMOUS IMPACTS ON
TEMPERATURES TODAY.
WEST OF THE FRONT THERE IS A THIN BUT EXPANSIVE DECK OF LOW
STRATUS WITH PATCHIER CIRRUS ALOFT. VISIBLE SATELLITE, WEBCAMS,
AND A LOOK OUT THE WINDOW REVEALS THERE ARE SOME THIN SPOTS IN
THIS LOW STRATUS CURRENTLY. WITH VAD WIND PROFILES INDICATING EAST
AND SOUTHEAST WINDS DOWN AS LOW AS 1000 FEET AGL...IT WON`T TAKE
MUCH TO ERODE THE THIN LAYER OF NE WINDS AND "JUMP" THE FRONT
ONSHORE. FORECAST HIGHS RANGE FROM THE MID 60S IN THE WILMINGTON
AREA WITH LOWER 60S ALONG THE COAST WEST OF CAPE FEAR. HIGHS
SHOULD REACH THE UPPER 50S TO AROUND 60 INLAND. ALL OF THESE
TEMPERATURES WILL BE ACHIEVED VERY LATE IN THE DAY AS WARM
ADVECTION MAY BE MORE IMPORTANT THAN INSOLATION.
AS IS TYPICAL, MODELS PAINT A VARIETY OF FORECAST POSITIONS FOR
THE FRONT. THE 06Z NAM WAS THE FASTEST TO BRING THE FRONT IN,
WHILE THE 00Z ARW-NMM WAS THE SLOWEST. AN MEDIAN TIME WAS JUST
AFTER SUNSET ALONG THE EAST-FACING BEACHES OF CAPE FEAR, WITH
WINDS TURNING SOUTHERLY THROUGHOUT THE AREA INCLUDING FAR INLAND
DURING THE EVENING HOURS AS THE COLD FRONT OFF THE WEST BECOMES
THE PRIMARY FEATURE AFFECTING THE PRESSURE GRADIENT AND LOW-LEVEL
WINDS.
RADAR/SATELLITE IMAGES SHOWS WAVES OF SHOWERS DEVELOPING OVER THE
GULF STREAM MOVING NORTHWESTWARD. THE HRRR AND HRRRX MODELS BOTH
SHOW THESE IMPACTING THE COAST THIS AFTERNOON BEGINNING BETWEEN
2-4 PM. POPS HAVE BEEN INCREASED TO 50-80 PERCENT DURING THE
AFTERNOON HOURS. PRECIP CHANCES INLAND ARE LESS CERTAIN GIVEN MUCH
LESS ATLANTIC TRANSPORT OF MOISTURE THAT FAR WEST PLUS OVERALL
WEAK FORCING. MEASURABLE RAIN OVER THE INLAND PEE DEE REGION WILL
PROBABLY FOCUS MORE ON ANY PRECIP AHEAD OF THE COLD FRONT LATE
TONIGHT.
SEVERE WEATHER POTENTIAL APPEARS QUITE LIMITED GIVEN SURFACE-BASED
INSTABILITY REMAINING NEAR ZERO TODAY AND TONIGHT. ALTHOUGH
ELEVATED INSTABILITY MAY GROW TO 400-600 J/KG...FAIRLY WEAK UPPER
LEVEL SUPPORT AND THE PRESENCE OF A LARGE DRY SLOT ALOFT THIS
EVENING WILL TEND TO REMOVE CONVECTION DURING THE TIME WHEN THE
BEST WIND SHEAR WILL BE PRESENT. WHILE I CANNOT RULE OUT SEVERE
WEATHER COMPLETELY, THIS DOES NOT APPEAR TO BE A VERY CONCERNING
SETUP AT THIS TIME.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 300 AM SATURDAY...STRONG COLD FRONT COMES THROUGH TO START
THE PERIOD AND FOR A FEW DAYS NOW GETTING SUNDAY`S HIGH
TEMPERATURE SEEMS AWFULLY TRICKY AS IT WILL LIKELY BE IN THE
MORNING IF NOT PREDAWN. LINGERING COASTAL SHOWERS TO START THE
PERIOD, IF ANY, WILL QUICKLY SCOOT OFFSHORE IN THE STRONG COLD AND
DRY ADVECTION REGIME. 850 TEMPS PLUNGE TO ABOUT -2C SUNDAY NIGHT
BRINGING SOME SEASONABLE MID 30S AREA-WIDE. WITH NO REAL RECOVERY
IN LOW LEVEL THERMAL FIELDS ON MONDAY AFTERNOON HIGHS A SOLID
CATEGORY BELOW NORMAL WITH HIGHS IN THE MID TO UPPER 40S.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 300 AM SATURDAY...HIGH PRESSURE ON TUESDAY IS SUPPRESSED TO
OUR SOUTH AND WEST ON TUESDAY WITH THE APPROACH OF A STRONG UPPER
TROUGH AND MOISTURE-DEPRIVED COLD FRONT SLATED FOR A TUESDAY NIGHT
PASSAGE AFTER A SEASONABLE TO SLIGHTLY COOL TUESDAY TEMPERATURES
WILL TAKE A TURN DOWNWARD POSSIBLY FOR THE REMAINDER OF THE PERIOD
THOUGH MOST OF THE TIME CLOUD COVER WILL BE LOW END PARTLY CLOUDY
IF NOT LESS. THIS WILL CHANGE ON THURSDAY AS SOME MOISTURE STREAMS
IN ALOFT AHEAD OF A SOUTHERN BRANCH DISTURBANCE. THIS FEATURE MAY
BRING RAIN CHANCES ON FRIDAY.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
AS OF 18Z...CLEARING LINE WORKING WESTWARD FROM SOUTHEAST NC
SHOULD WORK THROUGH ALL COASTAL TERMINALS IN THE NEXT 2 TO 4
HOURS AND RESULT IN PREVAILING VFR CONDITIONS WITH TEMPO MVFR
CIGS DUE TO SHRA AND THE ASSOCIATED CIGS THIS AFTERNOON INTO
TONIGHT. INLAND TAF SITES LIKELY TO RETAIN IFR CIGS UNTIL WARM
FRONTAL PASSAGE IN THE 04Z TO 08Z WINDOW BUT SHOWERS
COULD RESULT IN MVFR CONDITIONS AFTER PREDOMINANT IFR LIFTS.
WINDS WILL SHIFT FROM NE TO E AT 5 TO 10 KT TO SE TO S AFTER
THE WARM FRONT LIFTS THROUGH. VFR CONDITIONS EXPECTED ALL
TERMINALS ON SW FLOW AFT 12Z THE 10TH.
EXTENDED OUTLOOK...EXPECT VFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1230 AM SATURDAY...FEW CHANGES ARE NEEDED WITH THIS NOON
UPDATE. LIGHT SHOWERS HAVE ALREADY MOVED INTO THE WATERS NORTH OF
CAPE FEAR AND WILL REACH THE REMAINDER OF THE WATERS SOUTH OF CAPE
FEAR BY LATE THIS AFTERNOON/EARLY THIS EVENING. WE ARE SEEING SOME
HEAVIER SHOWERS AND THUNDERSTORMS OUT OVER THE GULF STREAM...SOME
OF WHICH MAY MAKE IT INSIDE 20 MILES BY SUNSET. WINDS/SEAS ARE
IN-LINE WITH PREVIOUS FORECASTS. DISCUSSION FROM 930 AM FOLLOWS...
A WARM FRONT/COASTAL TROUGH NEAR THE WESTERN EDGE OF THE GULF
STREAM WILL MOVE WESTWARD TODAY, REACHING THE COAST OF CAPE FEAR
EARLY THIS EVENING. THE FRONT SHOULD THEN JUMP INLAND ALLOWING
WINDS TO BECOME SOUTHERLY ALONG THE SOUTH CAROLINA COAST TOO.
UNTIL THEN, NORTHERLY WINDS WILL CONTINUE ALONG THE COAST WITH
WIND SPEEDS UP TO 20 KNOTS AT TIMES IN A FAIRLY TIGHT PRESSURE
GRADIENT. THIS HAS BUILT SEAS UP TO 5 FEET NEAR AND NORTH OF CAPE
FEAR...AND AN EXERCISE CAUTION HEADLINE WILL REMAIN POSTED THERE
UNTIL 11 AM.
SHOWERS DEVELOPING OVER THE GULF STREAM ARE MOVING NORTHWESTWARD
AND SHOULD OVERSPREAD THE CAPE FEAR AREA AND MYRTLE BEACH WATERS
THIS AFTERNOON. ISOLATED THUNDERSTORMS ARE POSSIBLE TOO. AFTER A
LULL DURING THE EVENING HOURS, ANOTHER WAVE OF SHOWERS AND STORMS MAY
PUSH ACROSS THE AREA AHEAD OF THE COLD FRONT LATE TONIGHT.
SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 300 AM SATURDAY...A HEALTHY COLD FRONT WITH APPRECIABLE
DYNAMICS ALOFT CROSSES EARLY SUNDAY. WIND AND SEAS SHOULD READILY
RAMP UP TO ADVISORY LEVELS WHERE THEY WILL REMAIN MUCH OF SUNDAY
NIGHT AS WINDS VEER TO W AND THEN NW. LATER SUNDAY NIGHT INTO
MONDAY WILL FEATURE A CONSIDERABLE DECREASE IN BOTH WIND AND SEAS
AS HIGH PRESSURE BUILDS INTO THE GULF STATES AND A RIDGE AXIS
POKES INTO THE CAROLINAS AND MID ATLANTIC REGION EASING THE
GRADIENT ALONG MOST OF THE EAST COAST.
LONG TERM /TUESDAY THROUGH WEDNESDAY/...
AS OF 300 AM SATURDAY...A VERY LIGHT GRADIENT IN PLACE ON TUESDAY
AS THE POST-FRONTAL HIGH SINKS INTO THE GULF STATES AND WEAKENS
CONSIDERABLY. A MODERATELY STRONG COLD FRONT COMES THROUGH TUESDAY
NIGHT WITH GOOD DYNAMICS IN THE LOW TO MID LEVELS FOR SOME FAIRLY
STRONG WINDS THAT COULD YIELD SCEC FOR EITHER WIND OR SEAS. THIS
POST-FRONTAL HIGH WILL NOT BE SO QUICK TO WEAKEN NOR ENTER THE
AREA ON WEDNESDAY KEEPING THE GRADIENT A BIT TIGHTER BUT PROBABLY
NOT TO WHERE HEADLINES WILL BE NEEDED.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...MBB
NEAR TERM...TRA
SHORT TERM...MBB
LONG TERM...MBB
AVIATION...RAN
MARINE...
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
951 AM EST SAT JAN 9 2016
.SYNOPSIS...
A WARM FRONT WILL LIFT NORTH ACROSS THE AREA LATE IN THE DAY INTO
THIS EVENING. A STRONG COLD FRONT WILL SWEEP ACROSS THE AREA
EARLY SUNDAY MORNING. SHOWERS AND SOME THUNDERSTORMS WILL REMAIN
IN THE FORECAST UNTIL THE FRONT SWEEPS TO OUR EAST. A SECONDARY
COLD FRONT WILL MOVE ACROSS THE AREA TUESDAY NIGHT. TEMPERATURES
WILL BE BELOW NORMAL FOR MUCH OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 930 AM SATURDAY...THIS IS A VERY COMPLEX FORECAST TODAY AND
TONIGHT WITH PLENTY OF OPPORTUNITY FOR ERROR. A WARM FRONT/COASTAL
TROUGH NEAR THE WESTERN EDGE OF THE GULF STREAM WILL WALK WESTWARD
TOWARD THE COAST...MOVING ONSHORE SOMETIME EARLY THIS EVENING. THE
PRECISE TIMING OF THE FRONTAL PASSAGE WILL HAVE ENORMOUS IMPACTS
ON TEMPERATURES TODAY.
WEST OF THE FRONT THERE IS A THIN BUT EXPANSIVE DECK OF LOW
STRATUS WITH PATCHIER CIRRUS ALOFT. VISIBLE SATELLITE, WEBCAMS,
AND A LOOK OUT THE WINDOW REVEALS THERE ARE SOME THIN SPOTS IN
THIS LOW STRATUS CURRENTLY. WITH VAD WIND PROFILES INDICATING EAST
AND SOUTHEAST WINDS DOWN AS LOW AS 1000 FEET AGL...IT WON`T TAKE
MUCH TO ERODE THE THIN LAYER OF NE WINDS AND "JUMP" THE FRONT
ONSHORE. FORECAST HIGHS RANGE FROM THE MID 60S IN THE WILMINGTON
AREA WITH LOWER 60S ALONG THE COAST WEST OF CAPE FEAR. HIGHS
SHOULD REACH THE UPPER 50S TO AROUND 60 INLAND. ALL OF THESE
TEMPERATURES WILL BE ACHIEVED VERY LATE IN THE DAY AS WARM
ADVECTION MAY BE MORE IMPORTANT THAN INSOLATION.
AS IS TYPICAL, MODELS PAINT A VARIETY OF FORECAST POSITIONS FOR
THE FRONT. THE 06Z NAM WAS THE FASTEST TO BRING THE FRONT IN,
WHILE THE 00Z ARW-NMM WAS THE SLOWEST. AN MEDIAN TIME WAS JUST
AFTER SUNSET ALONG THE EAST-FACING BEACHES OF CAPE FEAR, WITH
WINDS TURNING SOUTHERLY THROUGHOUT THE AREA INCLUDING FAR INLAND
DURING THE EVENING HOURS AS THE COLD FRONT OFF THE WEST BECOMES
THE PRIMARY FEATURE AFFECTING THE PRESSURE GRADIENT AND LOW-LEVEL
WINDS.
RADAR/SATELLITE IMAGES SHOWS WAVES OF SHOWERS DEVELOPING OVER THE
GULF STREAM MOVING NORTHWESTWARD. THE HRRR AND HRRRX MODELS BOTH
SHOW THESE IMPACTING THE COAST THIS AFTERNOON BEGINNING BETWEEN
2-4 PM. POPS HAVE BEEN INCREASED TO 50-80 PERCENT DURING THE
AFTERNOON HOURS. PRECIP CHANCES INLAND ARE LESS CERTAIN GIVEN MUCH
LESS ATLANTIC TRANSPORT OF MOISTURE THAT FAR WEST PLUS OVERALL
WEAK FORCING. MEASURABLE RAIN OVER THE INLAND PEE DEE REGION WILL
PROBABLY FOCUS MORE ON ANY PRECIP AHEAD OF THE COLD FRONT LATE
TONIGHT.
SEVERE WEATHER POTENTIAL APPEARS QUITE LIMITED GIVEN SURFACE-BASED
INSTABILITY REMAINING NEAR ZERO TODAY AND TONIGHT. ALTHOUGH
ELEVATED INSTABILITY MAY GROW TO 400-600 J/KG...FAIRLY WEAK UPPER
LEVEL SUPPORT AND THE PRESENCE OF A LARGE DRY SLOT ALOFT THIS
EVENING WILL TEND TO REMOVE CONVECTION DURING THE TIME WHEN THE
BEST WIND SHEAR WILL BE PRESENT. WHILE I CANNOT RULE OUT SEVERE
WEATHER COMPLETELY, THIS DOES NOT APPEAR TO BE A VERY CONCERNING
SETUP AT THIS TIME.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 300 AM SATURDAY...STRONG COLD FRONT COMES THROUGH TO START
THE PERIOD AND FOR A FEW DAYS NOW GETTING SUNDAY`S HIGH
TEMPERATURE SEEMS AWFULLY TRICKY AS IT WILL LIKELY BE IN THE
MORNING IF NOT PREDAWN. LINGERING COASTAL SHOWERS TO START THE
PERIOD, IF ANY, WILL QUICKLY SCOOT OFFSHORE IN THE STRONG COLD AND
DRY ADVECTION REGIME. 850 TEMPS PLUNGE TO ABOUT -2C SUNDAY NIGHT
BRINGING SOME SEASONABLE MID 30S AREA-WIDE. WITH NO REAL RECOVERY
IN LOW LEVEL THERMAL FIELDS ON MONDAY AFTERNOON HIGHS A SOLID
CATEGORY BELOW NORMAL WITH HIGHS IN THE MID TO UPPER 40S.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 300 AM SATURDAY...HIGH PRESSURE ON TUESDAY IS SUPPRESSED TO
OUR SOUTH AND WEST ON TUESDAY WITH THE APPROACH OF A STRONG UPPER
TROUGH AND MOISTURE-DEPRIVED COLD FRONT SLATED FOR A TUESDAY NIGHT
PASSAGE AFTER A SEASONABLE TO SLIGHTLY COOL TUESDAY TEMPERATURES
WILL TAKE A TURN DOWNWARD POSSIBLY FOR THE REMAINDER OF THE PERIOD
THOUGH MOST OF THE TIME CLOUD COVER WILL BE LOW END PARTLY CLOUDY
IF NOT LESS. THIS WILL CHANGE ON THURSDAY AS SOME MOISTURE STREAMS
IN ALOFT AHEAD OF A SOUTHERN BRANCH DISTURBANCE. THIS FEATURE MAY
BRING RAIN CHANCES ON FRIDAY.
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
AS OF 12Z...IFR OR LOWER CONDITIONS ONGOING AND ENVIRONMENT
REMAINS CONDUCIVE FOR THESE CONDITIONS TO PERSIST THROUGH
18Z.
HIGH CONFIDENCE WE WILL SEE PREDOMINATELY IFR CONDITIONS
THROUGH A GOOD CHUNK OF THE FORECAST PERIOD. CIGS MAY IMPROVE
TO MVFR AFT 18Z BUT IFR CONDITIONS COULD RETURN AFTER SUNSET.
A WARM FRONT MOVING THROUGH THE AREA OVERNIGHT SHOULD BRING AN
END TO THE IFR CONDITIONS IN THE 04Z TO 08Z WINDOW BUT SHOWERS
COULD RESULT IN MVFR CONDITIONS AFTER PREDOMINANT IFR LIFTS.
EXTENDED OUTLOOK...POTENTIAL FOR ADDITIONAL IFR-MVFR EARLY SUNDAY.
OTHERWISE EXPECT VFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 930 AM SATURDAY...A WARM FRONT/COASTAL TROUGH NEAR THE
WESTERN EDGE OF THE GULF STREAM WILL MOVE WESTWARD TODAY,
REACHING THE COAST OF CAPE FEAR EARLY THIS EVENING. THE FRONT
SHOULD THEN JUMP INLAND ALLOWING WINDS TO BECOME SOUTHERLY ALONG
THE SOUTH CAROLINA COAST TOO. UNTIL THEN, NORTHERLY WINDS WILL
CONTINUE ALONG THE COAST WITH WIND SPEEDS UP TO 20 KNOTS AT TIMES
IN A FAIRLY TIGHT PRESSURE GRADIENT. THIS HAS BUILT SEAS UP TO 5
FEET NEAR AND NORTH OF CAPE FEAR...AND AN EXERCISE CAUTION
HEADLINE WILL REMAIN POSTED THERE UNTIL 11 AM.
SHOWERS DEVELOPING OVER THE GULF STREAM ARE MOVING NORTHWESTWARD
AND SHOULD OVERSPREAD THE CAPE FEAR AREA AND MYRTLE BEACH WATERS
THIS AFTERNOON. ISOLATED THUNDERSTORMS ARE POSSIBLE TOO. AFTER A
LULL DURING THE EVENING HOURS, ANOTHER WAVE OF SHOWERS AND STORMS MAY
PUSH ACROSS THE AREA AHEAD OF THE COLD FRONT LATE TONIGHT.
SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 300 AM SATURDAY...A HEALTHY COLD FRONT WITH APPRECIABLE
DYNAMICS ALOFT CROSSES EARLY SUNDAY. WIND AND SEAS SHOULD READILY
RAMP UP TO ADVISORY LEVELS WHERE THEY WILL REMAIN MUCH OF SUNDAY
NIGHT AS WINDS VEER TO W AND THEN NW. LATER SUNDAY NIGHT INTO
MONDAY WILL FEATURE A CONSIDERABLE DECREASE IN BOTH WIND AND SEAS
AS HIGH PRESSURE BUILDS INTO THE GULF STATES AND A RIDGE AXIS
POKES INTO THE CAROLINAS AND MID ATLANTIC REGION EASING THE
GRADIENT ALONG MOST OF THE EAST COAST.
LONG TERM /TUESDAY THROUGH WEDNESDAY/...
AS OF 300 AM SATURDAY...A VERY LIGHT GRADIENT IN PLACE ON TUESDAY
AS THE POST-FRONTAL HIGH SINKS INTO THE GULF STATES AND WEAKENS
CONSIDERABLY. A MODERATELY STRONG COLD FRONT COMES THROUGH TUESDAY
NIGHT WITH GOOD DYNAMICS IN THE LOW TO MID LEVELS FOR SOME FAIRLY
STRONG WINDS THAT COULD YIELD SCEC FOR EITHER WIND OR SEAS. THIS
POST-FRONTAL HIGH WILL NOT BE SO QUICK TO WEAKEN NOR ENTER THE
AREA ON WEDNESDAY KEEPING THE GRADIENT A BIT TIGHTER BUT PROBABLY
NOT TO WHERE HEADLINES WILL BE NEEDED.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...COASTAL FLOOD ADVISORY UNTIL 11 AM EST THIS MORNING FOR NCZ107.
MARINE...NONE.
&&
$$
SYNOPSIS...MBB
NEAR TERM...TRA
SHORT TERM...MBB
LONG TERM...MBB
AVIATION...RAN
AREA FORECAST DISCUSSION
NWS RALEIGH NC
610 AM EST SAT JAN 09 2016
.SYNOPSIS...A RIDGE OF COOL HIGH PRESSURE AT THE SURFACE WITH
PLENTIFUL MOISTURE ALOFT WILL KEEP UNSETTLED WEATHER THROUGH
TONIGHT... AS A STRONG STORM SYSTEM APPROACHES FROM THE WEST AND
MOVES THROUGH THE REGION. THIS SYSTEM WILL EXIT ON SUNDAY... WITH
CLEARING SKIES AND DRIER WEATHER THROUGH EARLY NEXT WEEK.
&&
.NEAR TERM /TODAY THROUGH TONIGHT/...
AS OF 240 AM SATURDAY...
THROUGH THIS MORNING... WIDESPREAD FOG AND THICK STRATUS ARE LIKELY
TO PERSIST WITHIN THE WEDGE REGIME... FEATURING A DAMMING SURFACE
HIGH CENTERED OFF THE CANADIAN MARITIMES NOSING SW INTO NC... CAPPED
BY WEAK BUT STEADY MOIST UPGLIDE. BLOCKED BY THE MOUNTAINS TO THE
WEST AND A FRONTAL ZONE WELL TO OUR SOUTH AND SE... THE WEDGE SHOULD
STAY LOCKED IN WELL INTO THE MORNING GIVEN THE STAGNANT SURFACE
AIR... PROFOUND CLOUD DEPTH... AND LACK OF ANY MECHANISM TO DISPERSE
IT IN THE VERTICAL. THE HRRR AND HRRR-X ARE STILL SHOWING INCREASING
FOG DENSITY THROUGH DAYBREAK... AND WHILE THIS IS FAR FROM CERTAIN
GIVEN THE EXTENT OF STRATUS... WILL KEEP A CLOSE EYE ON FOG
TRENDS... AND DENSE FOG ADVISORY MAY BE NEEDED THIS MORNING. THE
MOIST UPGLIDE DOESN`T APPEAR TO BE STRONG OR DEEP ENOUGH FOR
ANYTHING MORE THAN PATCHY DRIZZLE OVER THE NEXT SEVERAL HOURS... AND
OTHER FORCING MECHANISMS ARE LACKING AS WELL GIVEN THE DEPARTURE TO
OUR NE OF A BATCH OF MID LEVEL VORTICITY... SO POPS THROUGH THIS
MORNING WILL BE LOW. TEMPS WILL BE SLOW TO RISE THROUGH THE UPPER
40S AND LOW-MID 50S THIS MORNING.
MIDDAY TODAY THROUGH TONIGHT: THE ACTIVE SOUTHERN STREAM REACHES ITS
PEAK IMPACT ON THE SOUTHEAST STATES LATE THIS AFTERNOON AND TONIGHT
WITH PASSAGE OF A POTENT MID LEVEL SHORTWAVE TROUGH AND SURFACE LOW
TO OUR WEST AND NW... MOVING FROM THE LOWER MISS VALLEY NEAR MIDDAY
THROUGH THE TN AND ERN OH VALLEY THROUGH TONIGHT. WHILE THE CHANCE
OF EVERYONE SEEING AT LEAST SOME SHOWERS (AND PERHAPS A STORM OR
TWO... MORE ON THAT LATER) IS HIGH CONSIDERING THE PROJECTIONS OF
MUCH ABOVE NORMAL PW (0.90-1.20")... IT APPEARS THAT THE BULK OF THE
DYNAMIC FORCING FOR ASCENT WILL HOLD TO OUR WEST AND NORTH. THESE
MECHANISMS INCLUDES THE MID LEVEL DPVA WITH THE SHORTWAVE TROUGH AS
WELL AS THE STRONGEST UPPER DIVERGENCE WITH THE LEFT EXIT REGION OF
THE SUBTROPICAL JET... BOTH OF WHICH TAKE A PATH NW OF CENTRAL NC.
BUT THERE SHOULD STILL BE A STRONG INFLUX OF LOWER LEVEL MOISTURE...
FOCUSED INTO CENTRAL AND ERN NC OUT AHEAD OF A WEAK SURFACE LOW NOW
OVER SOUTH FLA AND EXPECTED TO TRACK NORTHWARD TODAY AND THROUGH
CENTRAL NC TONIGHT... DRAWING ENOUGH ATLANTIC MOISTURE INTO THE AREA
FOR A PERIOD OF CATEGORICAL POPS... FOCUSING LATE AFTERNOON THROUGH
TONIGHT... WITH GREATEST COVERAGE AND DURATION OCCURRING ACROSS THE
NRN AND ERN FORECAST AREA. AS THIS SURFACE LOW APPROACHES AND DRAWS
THE COASTAL WEDGE FRONT WESTWARD INTO THE NC COASTAL PLAIN THIS
EVENING/TONIGHT... WEAK INSTABILITY (PEAKING AT A MUCAPE OF ABOUT
500-1000 J/KG TONIGHT) ALONG WITH IMPRESSIVE DEEP LAYER SHEAR AOA 50
KTS COULD SUPPORT A FEW POCKETS OF STRONGER CONVECTION... MOST
LIKELY (ACCORDING TO THE LATEST MODEL RUNS) DURING THE EARLY TO MID
EVENING HOURS. IT`S UNCLEAR WHETHER OR NOT ANY WEAK INSTABILITY WILL
BE ACHIEVED DURING THE TIME OF GREATEST LOW LEVEL SHEAR (0-3 KM SRH
PREDICTED TO REACH 300-400 M2/S2 ON THE NAM AND ABOUT HALF THAT ON
THE GFS)... WHICH WOULD INFLUENCE THE THREAT OF SUPERCELLS. SUCH A
SCENARIO SEEMS UNLIKELY BUT THE POTENTIAL WILL BE MONITORED. IF
SURFACE DEWPOINTS OVER OUR EAST CLIMB INTO THE UPPER 50S TO AROUND
60 AS EXPECTED HOWEVER... WITH WINDS BECOMING MORE UNIDIRECTIONAL (A
STRAIGHTENING HODOGRAPH)... THERE COULD BE A RISK OF BOWING SEGMENTS
AND STRONG STRAIGHT LINE WINDS TONIGHT. WILL RESTRICT AN ISOLATED
MENTION OF THUNDER TONIGHT FROM RALEIGH EAST AND SOUTH... ALONG AND
EAST OF THE ANTICIPATED TRACK OF THE WEAK SURFACE LOW. THE
WARM/WEDGE FRONT WILL SHIFT BACK EAST OVER THE COASTAL PLAIN LATE
TONIGHT AS THE OCCLUDED FRONT APPROACHES. EXPECT HIGHS FROM THE
UPPER 40S TO NEAR 50 IN THE TRIAD TO NEAR 60 IN OUR FAR SE (CLINTON
TO GOLDSBORO). TEMPS SHOULD SLIP JUST A FEW DEGREES EARLY TONIGHT...
TO THE MID 40S NW TO MID-UPPER 50S SE... WITH STEADY TEMPS OR A
SLIGHT RISE OVERNIGHT. -GIH
&&
.SHORT TERM /SUNDAY THROUGH SUNDAY NIGHT/...
AS OF 245 AM SATURDAY...
CONSENSUS OF THE LATEST MODELS IS TO SHIFT THE FRONTAL ZONE AND
ATTENDANT PRECIP EAST OUT OF THE COASTAL PLAIN SUN MORNING... WITH
THE ONSET OF BRISK AND GUSTY SW WINDS... SHIFTING TO WESTERLY LATE
IN THE DAY... AS THE SECONDARY COLD FRONT (TRAILING THE POTENT
SURFACE LOW THAT WILL ACCOMPANY THE VORTICITY/UPPER DIVERGENCE MAX
UP THROUGH LAKE ERIE/LAKE ONTARIO) PUSHES EAST INTO THE AREA LATE.
LOW LEVEL THICKNESSES START TO DROP SUNDAY MORNING BUT WILL
INITIALLY BE OFFSET BY INCREASING SUNSHINE AND THE DELAY IN COLD AIR
ADVECTION. HIGHS SHOULD BE IN THE MID 50S TO LOWER 60S EARLY IN THE
DAY... WITH READINGS SLIPPING LATER IN THE DAY. WITH THE TIGHT MSLP
GRADIENT IN THE WAKE OF THE LAKE ERIE LOW... SUSTAINED WINDS OF 15-
20 KTS APPEAR LIKELY... WITH FREQUENT GUSTS TO AROUND 30 MPH... BOTH
LIGHTENING UP LATE IN THE DAY. MOSTLY CLEAR SUN NIGHT WITH
DIMINISHING WINDS AND WINDS BECOMING WNW AS COLDER AIR RUSHES IN.
LOWS 25-33. -GIH
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 230 AM SATURDAY...
THE WORK WEEK BEGINS WITH HIGH PRESSURE IN PLACE OVER THE DEEP SOUTH
AND SOUTHWESTERLY FLOW ALOFT WHICH WILL KEEP CENTRAL NC DRY WITH
SLIGHTLY BELOW NORMAL TEMPERATURES IN PLACE AS HIGHS WILL CLIMB INTO
THE LOW TO MID 40S MONDAY WITH LOWS IN THE MID TO UPPER 20S.
MODERATION OF THE TEMPERATURES WILL INCREASE ON TUESDAY AS THICKNESS
VALUES RISE ABOUT 15 METERS...THUS CORRESPONDING TO ABOUT A 5 DEGREE
TEMPERATURE INCREASE FOR HIGHS ON TUESDAY. EXPECT MID 40S IN THE NW
PIEDMONT TO NEAR 50 DEGREES IN THE SOUTHEAST.
THAT IS WHERE THE MODERATION ENDS HOWEVER AS A COLD FRONT COMES
RUSHING INTO THE AREA TUESDAY NIGHT AND EARLY WEDNESDAY MORNING.
THIS WILL KEEP LOWS BELOW FREEZING WEDNESDAY MORNING...MID 20S TO
NEAR 30 DEGREES. A VERY STRONG PRESSURE GRADIENT WILL ACCOMPANY THE
FRONTAL PASSAGE AND GUSTY WINDS CAN BE EXPECTED. ACCORDING TO GFS
BUFFER SOUNDINGS...GUSTS COULD BE AS HIGH AS 25 KTS BASED ON
MOMENTUM TRANSFER TO THE SURFACE. RIGHT NOW MODELS REMAIN DRY...BUT
A BRIEF FLURRY OR TWO CANT BE RULED OUT AS THE UPPER TROUGH MOVES
THROUGH EARLY WEDNESDAY MORNING. NO IMPACTS ARE EXPECTED ASIDE FROM
VERY STRONG COLD AIR ADVECTION. THIS WILL KEEP MAX TEMPERATURES DOWN
IN THE UPPER 30S ACROSS THE NORTH TO LOW 40S IN THE SOUTHERN TIER.
LOWS IN THE MIDDLE 20S.
AFTER THE UPPER TROUGH CROSSES THE AREA WEDNESDAY MORNING...SURFACE
HIGH PRESSURE OVER THE SOUTH WILL BEGIN TO MIGRATE NORTHEASTWARD OVER
THE CAROLINAS...RELAXING THE PRESSURE GRADIENT. SOUTHWESTERLY FLOW
ALOFT WILL ONCE AGAIN MODERATE TEMPERATURES BACK INTO THE MID TO
UPPER 40S ON THURSDAY AFTERNOON WITH UPPER 20S TO LOWER 30S THURSDAY
NIGHT.
MODELS DIFFER IN THE APPROACH OF A LOW PRESSURE SYSTEM THAT FORMS
OVER THE WESTERN GULF OF MEXICO WEDNESDAY NIGHT AND ENDS UP
SOMEWHERE OFF OF THE EAST COAST ON FRIDAY MORNING. THE GFS SOLUTION
KEEPS THE LOW OFF OF THE COAST ON FRIDAY BUT THE ECMWF DOUSES
CENTRAL NC WITH PRECIPITATION FRIDAY MORNING. AT THIS TIME...IT
APPEARS MOST OF THE PRECIPITATION WOULD BE LIQUID AS TEMPERATURES
MODERATE INTO THE UPPER 40S TO LOWER 50S. AGAIN A FLURRY CANT BE
RULED OUT AT THE ONSET OF PRECIPITATION IN THE NORTHWEST PIEDMONT
BUT AS OF NOW THIS WOULD BE A RAIN EVENT. PLENTY OF TIME FOR THINGS
TO CHANGE AS THE PARENT LOW HASN`T BEGUN TO FORM YET.
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
AS OF 610 AM SATURDAY...
HIGH CONFIDENCE IN ADVERSE AVIATION CONDITIONS TONIGHT THROUGH MUCH
OF THIS MORNING... WITH ONLY SLOW IMPROVEMENT THEREAFTER. A WEDGE OF
COOL HIGH PRESSURE WILL CONTINUE TO NOSE IN FROM THE NE AT THE
SURFACE... WHILE DEEP MOISTURE STREAMS INTO THE AREA JUST OFF THE
SURFACE. THIS WILL KEEP DEEP LOW IFR/LIFR CLOUDS OVER THE REGION
WITH WIDESPREAD IFR/LIFR FOG. THE STAGNANT AIR MASS AND CLOUD DEPTH
WILL KEEP THESE ADVERSE CONDITIONS LOCKED IN LONGER THAN USUAL THIS
MORNING... AS IT MAY BE THE NOON HOUR OR EARLY AFTERNOON BEFORE WE
ACHIEVE MVFR CONDITIONS AT CENTRAL NC AIRFIELDS. AN APPROACHING
STORM SYSTEM FROM THE SOUTH AND SW WILL THEN BRING INCREASING CHANCE
FOR SHOWERS AND ISOLATED STORMS STARTING MID-LATE THIS AFTERNOON AND
LASTING THROUGH TONIGHT... WITH CONDITIONS AGAIN DETERIORATING TO
IFR BY THIS EVENING. AVIATION INTERESTS SHOULD BE ALERT FOR STRONG
WINDS FROM THE SE AT 1500-3000 FT AGL PRECEDING THE FRONT TONIGHT.
THESE STRONG WINDS FROM THE SE JUST OFF THE GROUND WILL CONTINUE TO
INCREASE AND VEER TO SOUTHWESTERLY LATE TONIGHT INTO SUN MORNING.
LOOKING BEYOND 12Z SUN MORNING... POOR AVIATION CONDITIONS WILL
PERSIST UNTIL PASSAGE OF A COLD FRONT FROM WEST TO EAST EARLY SUN
MORNING. CLEARING SKIES AND A TREND TO VFR ARE EXPECTED SUNDAY...
ALTHOUGH STRONG GUSTY WINDS FROM THE WEST ARE LIKELY POST-FRONT. VFR
CONDITIONS ARE EXPECTED TO DOMINATE THROUGH WED... ALTHOUGH GUSTY
WINDS MAY RETURN WITH A DRY COLD FRONT PASSAGE TUE NIGHT/WED. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...HARTFIELD
SHORT TERM...HARTFIELD
LONG TERM...ELLIS
AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
245 AM EST SAT JAN 09 2016
.SYNOPSIS...A RIDGE OF COOL HIGH PRESSURE AT THE SURFACE WITH
PLENTIFUL MOISTURE ALOFT WILL KEEP UNSETTLED WEATHER THROUGH
SATURDAY NIGHT... AS A STRONG STORM SYSTEM APPROACHES FROM THE WEST
AND MOVES THROUGH THE REGION. THIS SYSTEM WILL EXIT ON SUNDAY WITH
CLEARING SKIES AND DRIER WEATHER THROUGH EARLY NEXT WEEK.
&&
.NEAR TERM /TODAY THROUGH TONIGHT/...
AS OF 240 AM SATURDAY...
THROUGH THIS MORNING... WIDESPREAD FOG AND THICK STRATUS ARE LIKELY
TO PERSIST WITHIN THE WEDGE REGIME... FEATURING A DAMMING SURFACE
HIGH CENTERED OFF THE CANADIAN MARITIMES NOSING SW INTO NC... CAPPED
BY WEAK BUT STEADY MOIST UPGLIDE. BLOCKED BY THE MOUNTAINS TO THE
WEST AND A FRONTAL ZONE WELL TO OUR SOUTH AND SE... THE WEDGE SHOULD
STAY LOCKED IN WELL INTO THE MORNING GIVEN THE STAGNANT SURFACE
AIR... PROFOUND CLOUD DEPTH... AND LACK OF ANY MECHANISM TO DISPERSE
IT IN THE VERTICAL. THE HRRR AND HRRR-X ARE STILL SHOWING INCREASING
FOG DENSITY THROUGH DAYBREAK... AND WHILE THIS IS FAR FROM CERTAIN
GIVEN THE EXTENT OF STRATUS... WILL KEEP A CLOSE EYE ON FOG
TRENDS... AND DENSE FOG ADVISORY MAY BE NEEDED THIS MORNING. THE
MOIST UPGLIDE DOESN`T APPEAR TO BE STRONG OR DEEP ENOUGH FOR
ANYTHING MORE THAN PATCHY DRIZZLE OVER THE NEXT SEVERAL HOURS... AND
OTHER FORCING MECHANISMS ARE LACKING AS WELL GIVEN THE DEPARTURE TO
OUR NE OF A BATCH OF MID LEVEL VORTICITY... SO POPS THROUGH THIS
MORNING WILL BE LOW. TEMPS WILL BE SLOW TO RISE THROUGH THE UPPER
40S AND LOW-MID 50S THIS MORNING.
MIDDAY TODAY THROUGH TONIGHT: THE ACTIVE SOUTHERN STREAM REACHES ITS
PEAK IMPACT ON THE SOUTHEAST STATES LATE THIS AFTERNOON AND TONIGHT
WITH PASSAGE OF A POTENT MID LEVEL SHORTWAVE TROUGH AND SURFACE LOW
TO OUR WEST AND NW... MOVING FROM THE LOWER MISS VALLEY NEAR MIDDAY
THROUGH THE TN AND ERN OH VALLEY THROUGH TONIGHT. WHILE THE CHANCE
OF EVERYONE SEEING AT LEAST SOME SHOWERS (AND PERHAPS A STORM OR
TWO... MORE ON THAT LATER) IS HIGH CONSIDERING THE PROJECTIONS OF
MUCH ABOVE NORMAL PW (0.90-1.20")... IT APPEARS THAT THE BULK OF THE
DYNAMIC FORCING FOR ASCENT WILL HOLD TO OUR WEST AND NORTH. THESE
MECHANISMS INCLUDES THE MID LEVEL DPVA WITH THE SHORTWAVE TROUGH AS
WELL AS THE STRONGEST UPPER DIVERGENCE WITH THE LEFT EXIT REGION OF
THE SUBTROPICAL JET... BOTH OF WHICH TAKE A PATH NW OF CENTRAL NC.
BUT THERE SHOULD STILL BE A STRONG INFLUX OF LOWER LEVEL MOISTURE...
FOCUSED INTO CENTRAL AND ERN NC OUT AHEAD OF A WEAK SURFACE LOW NOW
OVER SOUTH FLA AND EXPECTED TO TRACK NORTHWARD TODAY AND THROUGH
CENTRAL NC TONIGHT... DRAWING ENOUGH ATLANTIC MOISTURE INTO THE AREA
FOR A PERIOD OF CATEGORICAL POPS... FOCUSING LATE AFTERNOON THROUGH
TONIGHT... WITH GREATEST COVERAGE AND DURATION OCCURRING ACROSS THE
NRN AND ERN FORECAST AREA. AS THIS SURFACE LOW APPROACHES AND DRAWS
THE COASTAL WEDGE FRONT WESTWARD INTO THE NC COASTAL PLAIN THIS
EVENING/TONIGHT... WEAK INSTABILITY (PEAKING AT A MUCAPE OF ABOUT
500-1000 J/KG TONIGHT) ALONG WITH IMPRESSIVE DEEP LAYER SHEAR AOA 50
KTS COULD SUPPORT A FEW POCKETS OF STRONGER CONVECTION... MOST
LIKELY (ACCORDING TO THE LATEST MODEL RUNS) DURING THE EARLY TO MID
EVENING HOURS. IT`S UNCLEAR WHETHER OR NOT ANY WEAK INSTABILITY WILL
BE ACHIEVED DURING THE TIME OF GREATEST LOW LEVEL SHEAR (0-3 KM SRH
PREDICTED TO REACH 300-400 M2/S2 ON THE NAM AND ABOUT HALF THAT ON
THE GFS)... WHICH WOULD INFLUENCE THE THREAT OF SUPERCELLS. SUCH A
SCENARIO SEEMS UNLIKELY BUT THE POTENTIAL WILL BE MONITORED. IF
SURFACE DEWPOINTS OVER OUR EAST CLIMB INTO THE UPPER 50S TO AROUND
60 AS EXPECTED HOWEVER... WITH WINDS BECOMING MORE UNIDIRECTIONAL (A
STRAIGHTENING HODOGRAPH)... THERE COULD BE A RISK OF BOWING SEGMENTS
AND STRONG STRAIGHT LINE WINDS TONIGHT. WILL RESTRICT AN ISOLATED
MENTION OF THUNDER TONIGHT FROM RALEIGH EAST AND SOUTH... ALONG AND
EAST OF THE ANTICIPATED TRACK OF THE WEAK SURFACE LOW. THE
WARM/WEDGE FRONT WILL SHIFT BACK EAST OVER THE COASTAL PLAIN LATE
TONIGHT AS THE OCCLUDED FRONT APPROACHES. EXPECT HIGHS FROM THE
UPPER 40S TO NEAR 50 IN THE TRIAD TO NEAR 60 IN OUR FAR SE (CLINTON
TO GOLDSBORO). TEMPS SHOULD SLIP JUST A FEW DEGREES EARLY TONIGHT...
TO THE MID 40S NW TO MID-UPPER 50S SE... WITH STEADY TEMPS OR A
SLIGHT RISE OVERNIGHT. -GIH
&&
.SHORT TERM /SUNDAY THROUGH SUNDAY NIGHT/...
AS OF 245 AM SATURDAY...
CONSENSUS OF THE LATEST MODELS IS TO SHIFT THE FRONTAL ZONE AND
ATTENDANT PRECIP EAST OUT OF THE COASTAL PLAIN SUN MORNING... WITH
THE ONSET OF BRISK AND GUSTY SW WINDS... SHIFTING TO WESTERLY LATE
IN THE DAY... AS THE SECONDARY COLD FRONT (TRAILING THE POTENT
SURFACE LOW THAT WILL ACCOMPANY THE VORTICITY/UPPER DIVERGENCE MAX
UP THROUGH LAKE ERIE/LAKE ONTARIO) PUSHES EAST INTO THE AREA LATE.
LOW LEVEL THICKNESSES START TO DROP SUNDAY MORNING BUT WILL
INITIALLY BE OFFSET BY INCREASING SUNSHINE AND THE DELAY IN COLD AIR
ADVECTION. HIGHS SHOULD BE IN THE MID 50S TO LOWER 60S EARLY IN THE
DAY... WITH READINGS SLIPPING LATER IN THE DAY. WITH THE TIGHT MSLP
GRADIENT IN THE WAKE OF THE LAKE ERIE LOW... SUSTAINED WINDS OF 15-
20 KTS APPEAR LIKELY... WITH FREQUENT GUSTS TO AROUND 30 MPH... BOTH
LIGHTENING UP LATE IN THE DAY. MOSTLY CLEAR SUN NIGHT WITH
DIMINISHING WINDS AND WINDS BECOMING WNW AS COLDER AIR RUSHES IN.
LOWS 25-33. -GIH
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 230 AM SATURDAY...
THE WORK WEEK BEGINS WITH HIGH PRESSURE IN PLACE OVER THE DEEP SOUTH
AND SOUTHWESTERLY FLOW ALOFT WHICH WILL KEEP CENTRAL NC DRY WITH
SLIGHTLY BELOW NORMAL TEMPERATURES IN PLACE AS HIGHS WILL CLIMB INTO
THE LOW TO MID 40S MONDAY WITH LOWS IN THE MID TO UPPER 20S.
MODERATION OF THE TEMPERATURES WILL INCREASE ON TUESDAY AS THICKNESS
VALUES RISE ABOUT 15 METERS...THUS CORRESPONDING TO ABOUT A 5 DEGREE
TEMPERATURE INCREASE FOR HIGHS ON TUESDAY. EXPECT MID 40S IN THE NW
PIEDMONT TO NEAR 50 DEGREES IN THE SOUTHEAST.
THAT IS WHERE THE MODERATION ENDS HOWEVER AS A COLD FRONT COMES
RUSHING INTO THE AREA TUESDAY NIGHT AND EARLY WEDNESDAY MORNING.
THIS WILL KEEP LOWS BELOW FREEZING WEDNESDAY MORNING...MID 20S TO
NEAR 30 DEGREES. A VERY STRONG PRESSURE GRADIENT WILL ACCOMPANY THE
FRONTAL PASSAGE AND GUSTY WINDS CAN BE EXPECTED. ACCORDING TO GFS
BUFFER SOUNDINGS...GUSTS COULD BE AS HIGH AS 25 KTS BASED ON
MOMENTUM TRANSFER TO THE SURFACE. RIGHT NOW MODELS REMAIN DRY...BUT
A BRIEF FLURRY OR TWO CANT BE RULED OUT AS THE UPPER TROUGH MOVES
THROUGH EARLY WEDNESDAY MORNING. NO IMPACTS ARE EXPECTED ASIDE FROM
VERY STRONG COLD AIR ADVECTION. THIS WILL KEEP MAX TEMPERATURES DOWN
IN THE UPPER 30S ACROSS THE NORTH TO LOW 40S IN THE SOUTHERN TIER.
LOWS IN THE MIDDLE 20S.
AFTER THE UPPER TROUGH CROSSES THE AREA WEDNESDAY MORNING...SURFACE
HIGH PRESSURE OVER THE SOUTH WILL BEGIN TO MIGRATE NORTHEASTWARD OVER
THE CAROLINAS...RELAXING THE PRESSURE GRADIENT. SOUTHWESTERLY FLOW
ALOFT WILL ONCE AGAIN MODERATE TEMPERATURES BACK INTO THE MID TO
UPPER 40S ON THURSDAY AFTERNOON WITH UPPER 20S TO LOWER 30S THURSDAY
NIGHT.
MODELS DIFFER IN THE APPROACH OF A LOW PRESSURE SYSTEM THAT FORMS
OVER THE WESTERN GULF OF MEXICO WEDNESDAY NIGHT AND ENDS UP
SOMEWHERE OFF OF THE EAST COAST ON FRIDAY MORNING. THE GFS SOLUTION
KEEPS THE LOW OFF OF THE COAST ON FRIDAY BUT THE ECMWF DOUSES
CENTRAL NC WITH PRECIPITATION FRIDAY MORNING. AT THIS TIME...IT
APPEARS MOST OF THE PRECIPITATION WOULD BE LIQUID AS TEMPERATURES
MODERATE INTO THE UPPER 40S TO LOWER 50S. AGAIN A FLURRY CANT BE
RULED OUT AT THE ONSET OF PRECIPITATION IN THE NORTHWEST PIEDMONT
BUT AS OF NOW THIS WOULD BE A RAIN EVENT. PLENTY OF TIME FOR THINGS
TO CHANGE AS THE PARENT LOW HASN`T BEGUN TO FORM YET.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
AS OF 1230 AM SATURDAY...
...WIDESPREAD FOG OVERNIGHT THROUGH SATURDAY MORNING...
HIGH CONFIDENCE IN ADVERSE AVIATION CONDITIONS TONIGHT THROUGH MUCH
OF SAT MORNING... WITH ONLY SLOW IMPROVEMENT THEREAFTER. A WEDGE OF
COOL HIGH PRESSURE WILL CONTINUE TO NOSE IN FROM THE NE AT THE
SURFACE... WHILE DEEP MOISTURE STREAMS INTO THE AREA JUST OFF THE
SURFACE. THIS WILL KEEP DEEP LOW IFR/LIFR CLOUDS OVER THE REGION
WITH WIDESPREAD IFR FOG... SOME OF IT NEARING LIFR/VLIFR LATE
TONIGHT. THE STAGNANT AIR MASS AND CLOUD DEPTH WILL KEEP THESE
ADVERSE CONDITIONS LOCKED IN LONGER THAN USUAL SAT MORNING... AS IT
MAY BE LATE MORNING OR THE NOON HOUR BEFORE WE ACHIEVE MVFR
CONDITIONS AT CENTRAL NC AIRFIELDS. AN APPROACHING STORM SYSTEM FROM
THE SOUTH AND SW WILL THEN BRING INCREASING CHANCE FOR SHOWERS AND
ISOLATED STORMS STARTING SAT AFTERNOON AND LASTING THROUGH SAT
NIGHT... WITH CONDITIONS AGAIN DETERIORATING TO IFR LATE SAT
AFTERNOON THROUGH SAT NIGHT. AVIATION INTERESTS SHOULD BE ALERT FOR
STRONG WINDS FROM THE SE AT 1500-3000 FT AGL PRECEDING THE FRONT SAT
NIGHT... PARTICULARLY AS WE APPROACH 06Z.
LOOKING BEYOND 06Z SAT NIGHT... POOR AVIATION CONDITIONS WILL
PERSIST UNTIL PASSAGE OF A COLD FRONT FROM WEST TO EAST LATE SAT
NIGHT INTO SUN MORNING. THE STRONG WINDS FROM THE SE JUST OFF THE
GROUND WILL CONTINUE TO INCREASE AND VEER TO SOUTHERLY OR
SOUTHWESTERLY LATE SAT NIGHT INTO SUN MORNING. THUNDERSTORMS ARE
POSSIBLE SAT NIGHT ESPECIALLY AFFECTING RWI/FAY. CLEARING SKIES AND
A TREND TO VFR ARE EXPECTED SUNDAY... ALTHOUGH STRONG GUSTY WINDS
FROM THE WEST ARE LIKELY POST-FRONT. VFR CONDITIONS ARE EXPECTED TO
DOMINATE THROUGH WED... ALTHOUGH GUSTY WINDS MAY RETURN WITH A DRY
COLD FRONT PASSAGE TUE NIGHT/WED. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...HARTFIELD
SHORT TERM...HARTFIELD
LONG TERM...ELLIS
AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
936 PM CST SUN JAN 10 2016
.UPDATE...
ISSUED AT 931 PM CST SUN JAN 10 2016
HAVE SOME ISSUES WITH TEMPERATURES TONIGHT. WARM FRONT ACROSS
SOUTHWEST NORTH DAKOTA ALREADY KEEPING TEMPERATURES IN THE LOWER
20S THIS EVENING ALTHOUGH BAKER IS 26 NOW VS 20 AT 6 PM.
TEMPERATURES RISES HELPED WITH GUSTY WEST/NORTHWEST WINDS BEHIND
THE FRONT. HRRR MODEL PRODUCES JUST A SMALL AREA OF LIGHT PRECIP
ACROSS THE SOUTHWEST THIS EVENING WHICH SEEMS TO FIT WITH CURRENT
TRENDS. UPDATED POPS AND TRENDED THE TEMPS UP A BIT OVERNIGHT.
UPDATE ISSUED AT 554 PM CST SUN JAN 10 2016
SURFACE HIGH PRESSURE OVER EASTERN NORTH DAKOTA WILL MOVE EAST
TONIGHT AS A LEE SIDE TROUGH REMAINS IN MONTANA. A WEAK H500
SHORTWAVE WILL TRACK ACROSS THE WESTERN PORTION OF THE STATE
TONIGHT. ASSOCIATED LOW LEVEL WARM ADVECTION AND CLOUDS ACROSS THE
WEST AND CENTRAL WILL FAVOR NON DIURNAL TEMPERATURES TONIGHT WITH
OVERNIGHT LOWS LIKELY THIS EVENING OR SHORTLY AFTER MIDNIGHT...
ESPECIALLY ACROSS THE JAMES RIVER VALLEY...FOLLOWED BY RISING
TEMPERATURES LATER TONIGHT. THIS FEATURE WILL BE FOLLOWED BY A
BIT MORE VIGOROUS SHORTWAVE ON MONDAY AFTERNOON BRINGING GUSTY
WINDS AND A CHANCE FOR SNOW. SO FAR THE CURRENT FORECAST SEEMS TO
BE TRACKING OK. WILL MAINLY UPDATE CURRENT CONDITIONS.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 315 PM CST SUN JAN 10 2016
GUSTY WINDS...DRIFTING AND POSSIBLY SOME BLOWING SNOW ALONG WITH
A CHANCE OF LIGHT FALLING SNOW ON MONDAY IS OUR MAIN FOCUS.
A QUICK-MOVING SHORTWAVE TROUGH IN NORTHWEST FLOW WILL CROSS THE
AREA TONIGHT. GIVEN MODEST QG-FORCING FORCING IN MODEL SOLUTIONS
AND SOME INCREASE IN RADAR ECHOES UPSTREAM IN MT AS OF 21 UTC...A
SLIGHT CHANCE OF LIGHT SNOW IS PRUDENT IN THE FORECAST TONIGHT AT
LEAST FOR A TIME IN MOST AREAS. BEFORE CLOUD COVER INCREASES WITH
THE APPROACH OF THAT WAVE...TEMPERATURES IN CENTRAL ND MAY TUMBLE
QUICKLY WITH SUNSET GIVEN LIGHT WINDS AND POOR RECOVERY TODAY. WE
THUS UNDERCUT GUIDANCE LOWS OVER CENTRAL ND TONIGHT...ESPECIALLY
IN THE JAMES RIVER VALLEY...WHERE WE HAVE LOWS OF -10 TO -15. THE
TEMPERATURES SHOULD EVENTUALLY RISE OVERNIGHT AS CLOUDS INCREASE.
ON MONDAY...ANOTHER...STRONGER SHORTWAVE TROUGH WILL INDUCE A NEW
ARCTIC SURGE WITH A SURFACE COLD FRONT TRANSITING THE AREA QUICKLY
DURING THE MIDDAY HOURS. DEEP-LAYER FORCING IS WEAK...BUT FORECAST
SOUNDINGS SUGGEST A SATURATED LAYER /STRATUS DECK/ BASED IN THE
DENDRITIC GROWTH ZONE...WHICH MAY LEAD TO A HIGH POP/LOW QPF TYPE
OF SITUATION WITH A SEVERAL-HOUR PERIOD OF LIGHT SNOW POSSIBLE. WE
EXPECT ACCUMULATIONS LESS THAN AN INCH OVER ALL BUT FAR SOUTHWEST
ND...WHERE TOTAL SNOWFALL COULD BE AROUND AN INCH SINCE OMEGA WILL
BE SOMEWHAT STRONGER CLOSER TO A LOW- TO MID-LEVEL BAROCLINIC ZONE.
WINDS WILL BE THE GREATER CONCERN...BUT THE 00 AND 12 UTC MODELS
HAVE GRADUALLY RELAXED WIND SPEEDS ALOFT AND BOUNDARY LAYER WINDS
FROM THE 12 UTC GFS AND NAM ONLY RAN 25-30 KT. THERE WILL ALSO BE
MODEST SURFACE PRESSURE RISES OF 3-5 MB/3 HR FOLLOWING THE FRONT.
THUS...WE DO EXPECT GUSTS TO 35 MPH MOST AREAS MONDAY AFTERNOON.
THE BAGGALEY BLOWING SNOW MODEL SUGGESTS THE PROBABILITY OF 1/2SM
VISIBILITY FROM PURE BLOWING SNOW IS ON THE FRINGES OF THE VALUES
WE WOULD TYPICALLY EXPECT TO REQUIRE A WINTER WEATHER ADVISORY AS
A RESULT OF AN OLD SNOW PACK AND LACK OF STRONGER LOW-LEVEL COLD
AIR ADVECTION. HOWEVER...THAT GUIDANCE ALSO SUGGESTS REDUCTIONS IN
VISIBILITY FROM LIGHT FALLING SNOW IN THE GUSTY WINDS MAY BE MORE
DRAMATIC...ALBEIT SHORTER-LIVED. ALL CONSIDERED...WE FELT THAT
THIS EVENT IS BEST-HANDLED USING A SPECIAL WEATHER STATEMENT. WE
WILL RELY ON LATER RAPID-REFRESH GUIDANCE AND OBSERVATIONAL TRENDS
TO DETERMINE IF FALLING SNOW WILL LAST LONG ENOUGH IN ANY ONE AREA
TO PRODUCE A LONGER-LIVED BLOWING SNOW ISSUE THAT MIGHT REQUIRE US
TO ISSUE AN ADVISORY. THE PROBABILITY OF BLOWING SNOW IS GREATEST
IN CENTRAL ND REGARDLESS...WHERE THE SNOW PACK IS DEEPEST.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 315 PM CST SUN JAN 10 2016
AFTER ANOTHER BELOW ZERO NIGHT MONDAY NIGHT WITH DANGEROUS WIND
CHILLS...A WARMING TREND ENSUES...THEN A CHANCE OF LIGHT SNOW
THURSDAY INTO FRIDAY WITH A COOLING TREND.
MONDAY NIGHT THE ARCTIC HIGH CENTER MOVES SOUTHEAST FROM
ALBERTA/SASKATCHEWAN AT SUNSET MONDAY EVENING...TO THE CENTRAL
DAKOTAS BY DAYBREAK TUESDAY MORNING. OVERNIGHT LOWS SHOULD RANGE
FROM AROUND 10 BELOW IN THE TURTLE MOUNTAIN REGION TO AROUND 5 ABOVE
IN THE FAR SOUTHWEST. ALTHOUGH NORTHWEST WINDS SHOULD BE DIMINISHING
THROUGH THE NIGHTTIME HOURS...DANGEROUS WIND CHILLS ARE EXPECTED TO
DEVELOP LATE MONDAY NIGHT ALONG AND NORTH OF A LINE FROM FROM AROUND
CROSBY IN THE NORTHWEST TO JAMESTOWN. THE DANGEROUS WIND CHILLS ARE
FORECAST TO LINGER THROUGH THE MORNING HOURS ON TUESDAY.
A WESTERN RIDGE CURRENTLY OVER THE WEST COAST PUSHES EAST ACROSS THE
ROCKIES AND EXPANDS INTO THE WESTERN PLAINS TUESDAY/TUESDAY
NIGHT...BRINGING WARM ADVECTION TO WESTERN NORTH DAKOTA DURING THE
DAY TUESDAY. A NOTICEABLE TEMPERATURE CONTRAST ON TUESDAY WITH HIGHS
ONLY EXPECTED TO BE AROUND ZERO IN THE TURTLE MOUNTAIN AREA...BUT
REACH INTO THE LOWER 20S IN THE SOUTHWEST.
WARMER ON WEDNESDAY AS THE WARM RIDGE PUSHES FARTHER EAST. HIGHS
WEDNESDAY AND THURSDAY FROM THE TEENS IN THE TURTLE MOUNTAINS TO THE
LOWER 30S IN THE SOUTHWEST.
ALONG WITH THE WARM ADVECTION THURSDAY...THE MODELS ARE INDICATING A
SHORTWAVE BREAKING DOWN THE WARMING RIDGE...INDICATING A MORE ACTIVE
PATTERN WITH A CHANCE OF LIGHT SNOW THURSDAY INTO FRIDAY ALONG
WITH A COOLING TREND.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 554 PM CST SUN JAN 10 2016
AT 6 PM CST...HIGH PRESSURE ACROSS THE RED RIVER VALLEY IS
FORECAST TO MOVE EAST TONIGHT. A WARM FRONT IN EASTERN MONTANA
WILL MOVE EAST TONIGHT FOLLOWED BY A FAST MOVING COLD FRONT ON
MONDAY. THIS WILL BRING AREAS MVFR CEILINGS TONIGHT FOLLOWED BY
GUSTY WINDS AND SNOW AND BLOWING SNOW MONDAY. NORTHWEST WINDS
GUSTING TO 30KTS AFTER 18Z MONDAY.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...WAA
SHORT TERM...CJS
LONG TERM...JV
AVIATION...WAA
AREA FORECAST DISCUSSION
NWS NORMAN OK
1205 AM CST SAT JAN 9 2016
.UPDATE...
A RELATIVELY SMALL BAND OF MODERATE PRECIPITATION CONTINUES TO
MOVE INTO OUR NORTH TEXAS COUNTIES IN THE PROXIMITY OF THE UPPER
LOW. LOW-LEVEL TEMPERATURES HAVE REMAINED UP THOUGH AS ALTUS
REMAINS 36 WITH PRIMARILY RAIN AND KNOX CITY IS 39. MAY HAVE A
SLIVER OF AIR COOL ENOUGH FOR SNOW IN THE QUANAH/HOLLIS AREA AS
CHILDRESS IS NOW REPORTING SNOW. WILL CONTINUE TO WATCH FOR
OVERLAP OF THIS PRECIP AND COOLER LOW-LEVEL TEMPERATURES OVERNIGHT
ACROSS SOUTHWEST AND CENTRAL. THE PRIMARY AREA OF SNOW MAY BE
ACROSS WEST CENTRAL OKLAHOMA WHERE SOMEWHAT HIGHER REFLECTIVITIES
PERSIST ACROSS CUSTER/DEWEY COUNTIES. WE DID RECEIVE A TWITTER
PICTURE OF AN INCH OF SNOW ACCUMULATION AT HAMMON ABOUT AN HOUR
AGO... SO COULD SEE SOME ISOLATED AREAS WITH A TOUCH MORE THAN 2
INCHES. BUT THIS BAND OF MODERATE PRECIP IS RATHER NARROW AND
OTHERWISE INTENSITY TRENDS HAVE BEEN DOWNWARD...SO MOST AREAS WILL
REMAIN LESS.
&&
.PREV DISCUSSION... /ISSUED 1049 PM CST FRI JAN 8 2016/
DISCUSSION...
AVIATION DISCUSSION FOR THE 06Z TAFS IS BELOW.
AVIATION...
THE TAFS REMAIN CHALLENGING OVER THE NEXT 24 HOURS. CONFIDENCE
IS RATHER LOW THROUGH 15Z.
THROUGH 12Z...GENERALLY THINK MVFR CONDITIONS WILL OCCUR IN MOST
LOCATIONS. PATCHES OF IFR/LIFR CONDITIONS WILL OCCUR AS WELL...
ESPECIALLY WHERE -SN OCCURS.
PRECIPITATION TYPE SHOULD BE -SN AT MOST SITES. KSPS MAY HAVE A
-RAPLSN MIX THROUGH 10Z.
AFTER 12Z...CONDITIONS WILL IMPROVE NORTH TO SOUTH. BELIEVE ALL
SITES WILL BE VFR BY 21Z. ANY -SN WILL END BY 16Z.
NORTH WINDS WILL BECOME GUSTY AT MANY SITES BY 12Z...THEN WEAKEN
AFTER 23Z.
MBS
PREV DISCUSSION... /ISSUED 959 PM CST FRI JAN 8 2016/
UPDATE...
COMPLICATED FORECAST THIS EVENING. UPPER LOW SPINNING NEAR LUBBOCK
WILL MOVE EAST-NORTHEAST TOWARD THE RED RIVER VALLEY. MEANWHILE
COLD LOW-LEVEL AIR IS FILTERING SOUTHEAST. LOW LEVELS ARE COOL
ENOUGH TO CHANCE PRECIP TO SNOW AS FAR SOUTH AS ERICK/ELK CITY.
RAP AND HRRR SHOW PRIMARY PRECIP BAND NEAR LUBBOCK MAY PIVOT UP
THE I-44 CORRIDOR FROM ROUGHLY CROWELL TO LAWTON TO OKLAHOMA
CITY... BUT WILL THE LOW LEVELS BE COOL ENOUGH FOR PRECIP TO BE
PRIMARILY SNOW WHEN MODERATE PRECIPITATION IS FALLING? WILL BE
WATCHING THIS CLOSELY TO SEE IF THE ADVISORY MAY NEED TO BE
EXPANDED SOUTHEAST A LITTLE BIT THIS EVENING OR OVERNIGHT.
MEANWHILE... THE PRECIPITATION IS LIGHTER FARTHER NORTH... BUT
DURATION OF LIGHT SNOW MAY STILL BE SUFFICIENT FOR AN INCH OR TWO
OF SNOW IN WESTERN AND PORTIONS OF NORTHERN OKLAHOMA... SO WILL
KEEP THE ADVISORY UP THERE. VISIBILITY IN THE AREAS OF SNOW IN
NORTHWEST OKLAHOMA AND THE TEXAS PANHANDLES HAVE GENERALLY BEEN
3-5 MILES SO IT DOES NOT SEEM LIKE IT WILL ACCUMULATE TOO QUICKLY.
DID ISSUE ONE UPDATE EARLIER THIS EVENING TO ACCOUNT FOR CURRENT
TRENDS... AND WILL LET THAT RIDE FOR THE NOW.
PREV DISCUSSION... /ISSUED 303 PM CST FRI JAN 8 2016/
DISCUSSION...
WE EARLIER ISSUED A WINTER WEATHER ADVISORY FOR MUCH OF OUR
FORECAST AREA...BASED ON VERY AGGRESSIVE SNOWFALL AMOUNTS
ADVERTISED BY MOST OF THE FORECAST MODELS AVAILABLE AT THE TIME.
MORE-RECENT TRENDS IN THE MODELS HAVE ADDED A GREAT DEAL OF
UNCERTAINTY TO THE FORECAST...BY PLACING SNOW BANDS IN VARYING
PLACES...WITH FAR LESS GEOGRAPHICAL/TEMPORAL AGREEMENT THAN
BEFORE. AS A RESULT...WE HAVE SMOOTHED THE SNOWFALL FORECAST A
LOT...REMOVING STORM TOTAL AMOUNTS GREATER THAN 2 INCHES. OUR BEST
ESTIMATE AT THIS TIME...HOWEVER...STILL SUPPORTS A WINTER WEATHER
ADVISORY OVER ESSENTIALLY THE SAME AREA AS BEFORE...JUST LESS
CERTAINTY ABOUT SNOWFALL TOTALS. THERE IS STILL A GOOD CHANCE THAT
A STRIPE OF LAND WILL BE COVERED WITH 2 TO 4 INCHES OF SNOW...BUT
IT IS MUCH HARDER TO SAY WHERE THAT STRIPE WILL BE.
SO...WE ARE MAKING NO CHANGES AT THIS ISSUANCE TO EITHER THE
TIMING OR THE GEOGRAPHICAL BOUNDARIES OF OUR ADVISORY. THE
SNOWFALL AMOUNTS HAVE BEEN LOWERED SIGNIFICANTLY IN THE AREA
ROUGHLY FROM MANGUM TO ENID. OTHERWISE...THERE IS NOT MUCH CHANGE
IN THIS PART OF THE FORECAST.
WE HAVE MADE SOME VERY SHORT-RANGE ADJUSTMENTS ALSO TO POPS TO
ACCOMMODATE THE CURRENT RADAR TRENDS. A BAND OF RAIN IS DEVELOPING
FROM NEAR WICHITA FALLS TO SHAWNEE...AND THIS MAY LATER CONVERT
INTO A SNOW BAND LATE TONIGHT...ONCE TEMPERATURES ALOFT FALL
ENOUGH TO MAKE THE CHANGEOVER.
SNOW SHOULD END DURING THE DAY TOMORROW...AND THERE IS NOT MUCH OF
INTEREST IN THE REST OF THE FORECAST. AFTER A COLDER-THAN-AVERAGE
WEEKEND...TEMPERATURES WILL BEGIN A SLOW WARMING TREND THAT WILL
LAST THROUGH NEXT WEEK. ANOTHER DISTURBANCE MAY BRING SOME SHOWERS
TO THE AREA ON THURSDAY.
OUN WATCHES/WARNINGS/ADVISORIES...
OK...WINTER WEATHER ADVISORY UNTIL NOON CST SATURDAY FOR OKZ004>025-
033>036.
TX...WINTER WEATHER ADVISORY UNTIL NOON CST SATURDAY FOR TXZ083.
$$
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 30 35 18 30 / 70 20 0 0
HOBART OK 29 37 18 33 / 70 10 0 0
WICHITA FALLS TX 34 42 22 39 / 60 20 0 0
GAGE OK 25 34 13 34 / 70 10 0 0
PONCA CITY OK 29 32 13 31 / 60 20 0 0
DURANT OK 37 41 24 37 / 60 20 0 0
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...WINTER WEATHER ADVISORY UNTIL NOON CST SATURDAY FOR OKZ004>025-
033>036.
TX...WINTER WEATHER ADVISORY UNTIL NOON CST SATURDAY FOR TXZ083.
&&
$$
AREA FORECAST DISCUSSION
NWS NORMAN OK
1049 PM CST FRI JAN 8 2016
.DISCUSSION...
AVIATION DISCUSSION FOR THE 06Z TAFS IS BELOW.
&&
.AVIATION...
THE TAFS REMAIN CHALLENGING OVER THE NEXT 24 HOURS. CONFIDENCE
IS RATHER LOW THROUGH 15Z.
THROUGH 12Z...GENERALLY THINK MVFR CONDITIONS WILL OCCUR IN MOST
LOCATIONS. PATCHES OF IFR/LIFR CONDITIONS WILL OCCUR AS WELL...
ESPECIALLY WHERE -SN OCCURS.
PRECIPITATION TYPE SHOULD BE -SN AT MOST SITES. KSPS MAY HAVE A
-RAPLSN MIX THROUGH 10Z.
AFTER 12Z...CONDITIONS WILL IMPROVE NORTH TO SOUTH. BELIEVE ALL
SITES WILL BE VFR BY 21Z. ANY -SN WILL END BY 16Z.
NORTH WINDS WILL BECOME GUSTY AT MANY SITES BY 12Z...THEN WEAKEN
AFTER 23Z.
MBS
&&
.PREV DISCUSSION... /ISSUED 959 PM CST FRI JAN 8 2016/
UPDATE...
COMPLICATED FORECAST THIS EVENING. UPPER LOW SPINNING NEAR LUBBOCK
WILL MOVE EAST-NORTHEAST TOWARD THE RED RIVER VALLEY. MEANWHILE
COLD LOW-LEVEL AIR IS FILTERING SOUTHEAST. LOW LEVELS ARE COOL
ENOUGH TO CHANCE PRECIP TO SNOW AS FAR SOUTH AS ERICK/ELK CITY.
RAP AND HRRR SHOW PRIMARY PRECIP BAND NEAR LUBBOCK MAY PIVOT UP
THE I-44 CORRIDOR FROM ROUGHLY CROWELL TO LAWTON TO OKLAHOMA
CITY... BUT WILL THE LOW LEVELS BE COOL ENOUGH FOR PRECIP TO BE
PRIMARILY SNOW WHEN MODERATE PRECIPITATION IS FALLING? WILL BE
WATCHING THIS CLOSELY TO SEE IF THE ADVISORY MAY NEED TO BE
EXPANDED SOUTHEAST A LITTLE BIT THIS EVENING OR OVERNIGHT.
MEANWHILE... THE PRECIPITATION IS LIGHTER FARTHER NORTH... BUT
DURATION OF LIGHT SNOW MAY STILL BE SUFFICIENT FOR AN INCH OR TWO
OF SNOW IN WESTERN AND PORTIONS OF NORTHERN OKLAHOMA... SO WILL
KEEP THE ADVISORY UP THERE. VISIBILITY IN THE AREAS OF SNOW IN
NORTHWEST OKLAHOMA AND THE TEXAS PANHANDLES HAVE GENERALLY BEEN
3-5 MILES SO IT DOES NOT SEEM LIKE IT WILL ACCUMULATE TOO QUICKLY.
DID ISSUE ONE UPDATE EARLIER THIS EVENING TO ACCOUNT FOR CURRENT
TRENDS... AND WILL LET THAT RIDE FOR THE NOW.
PREV DISCUSSION... /ISSUED 303 PM CST FRI JAN 8 2016/
DISCUSSION...
WE EARLIER ISSUED A WINTER WEATHER ADVISORY FOR MUCH OF OUR
FORECAST AREA...BASED ON VERY AGGRESSIVE SNOWFALL AMOUNTS
ADVERTISED BY MOST OF THE FORECAST MODELS AVAILABLE AT THE TIME.
MORE-RECENT TRENDS IN THE MODELS HAVE ADDED A GREAT DEAL OF
UNCERTAINTY TO THE FORECAST...BY PLACING SNOW BANDS IN VARYING
PLACES...WITH FAR LESS GEOGRAPHICAL/TEMPORAL AGREEMENT THAN
BEFORE. AS A RESULT...WE HAVE SMOOTHED THE SNOWFALL FORECAST A
LOT...REMOVING STORM TOTAL AMOUNTS GREATER THAN 2 INCHES. OUR BEST
ESTIMATE AT THIS TIME...HOWEVER...STILL SUPPORTS A WINTER WEATHER
ADVISORY OVER ESSENTIALLY THE SAME AREA AS BEFORE...JUST LESS
CERTAINTY ABOUT SNOWFALL TOTALS. THERE IS STILL A GOOD CHANCE THAT
A STRIPE OF LAND WILL BE COVERED WITH 2 TO 4 INCHES OF SNOW...BUT
IT IS MUCH HARDER TO SAY WHERE THAT STRIPE WILL BE.
SO...WE ARE MAKING NO CHANGES AT THIS ISSUANCE TO EITHER THE
TIMING OR THE GEOGRAPHICAL BOUNDARIES OF OUR ADVISORY. THE
SNOWFALL AMOUNTS HAVE BEEN LOWERED SIGNIFICANTLY IN THE AREA
ROUGHLY FROM MANGUM TO ENID. OTHERWISE...THERE IS NOT MUCH CHANGE
IN THIS PART OF THE FORECAST.
WE HAVE MADE SOME VERY SHORT-RANGE ADJUSTMENTS ALSO TO POPS TO
ACCOMMODATE THE CURRENT RADAR TRENDS. A BAND OF RAIN IS DEVELOPING
FROM NEAR WICHITA FALLS TO SHAWNEE...AND THIS MAY LATER CONVERT
INTO A SNOW BAND LATE TONIGHT...ONCE TEMPERATURES ALOFT FALL
ENOUGH TO MAKE THE CHANGEOVER.
SNOW SHOULD END DURING THE DAY TOMORROW...AND THERE IS NOT MUCH OF
INTEREST IN THE REST OF THE FORECAST. AFTER A COLDER-THAN-AVERAGE
WEEKEND...TEMPERATURES WILL BEGIN A SLOW WARMING TREND THAT WILL
LAST THROUGH NEXT WEEK. ANOTHER DISTURBANCE MAY BRING SOME SHOWERS
TO THE AREA ON THURSDAY.
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...WINTER WEATHER ADVISORY UNTIL NOON CST SATURDAY FOR OKZ004>025-
033>036.
TX...WINTER WEATHER ADVISORY UNTIL NOON CST SATURDAY FOR TXZ083.
&&
$$
26/17/17
AREA FORECAST DISCUSSION
NWS MEDFORD OR
916 AM PST SAT JAN 9 2016
.DISCUSSION...CURRENT RADAR SHOWS MOST OF THE PRECIPITATION IN
WESTERN SIKSYOU COUNTY THROUGH EASTERN JACKSON COUNTY AND
SOUTHWEST KLAMATH COUNTY AND MOVING EAST TO NORTHEAST. THE SHORT
TERM HRRR MODELS SUGGEST PRECIPITATION WILL GRADUALLY DECREASE
THIS AFTERNOON WITH MOST CONFINED TO NORTHERN CAL BY THIS EVENING.
HAVE ADJUSTED POPS AND QPF AMOUNTS HIGHER FOR NORTHERN CAL AND
EAST OF THE CASCADES THIS AFTERNOON. SNOW LEVELS WILL GRADUALLY
COME UP, BUT ONLY AROUND 4000 FEET. LIGHT SNOW IS EXPECTED TO
PERSIST INTO THE AFTERNOON NEAR OR ABOVE 4000 FEET, BUT ROAD
TEMPERATURES WILL WARM UP ENOUGH DURING THE DAY TO KEEP SNOW FROM
ACCUMULATING. CURRENT WINTER WEATHER ADVISORY IS DUE TO END AT 10
AM PST IN THE MOUNT SHASTA REGION WHICH LOOKS REASONABLE, SO
WE`LL LET IT EXPIRE. -PETRUCELLI
&&
.AVIATION...FOR THE 09/12Z TAF CYCLE...A WARM FRONT WILL BRING
WIDESPREAD RAIN TO SW OREGON THROUGH LATE THIS MORNING WITH
WIDESPREAD MVFR CIGS AND MOUNTAIN OBSCURATION. AREAS OF IFR CIGS
HAVE BEEN PERSISTENT ACROSS THE UMPQUA BASIN AND KRBG IS NOT
EXPECTED TO LIFT TO VFR UNTIL AROUND NOON. TO THE EAST EXPECT AREAS
OF IFR CIGS/VIS IN SNOW UNTIL MID MORNING...THEN CONDITIONS
IMPROVING TO MVFR CIGS. MOUNTAINS WILL BE OBSCURED. /FB
&&
.MARINE...UPDATED 215 AM PST SATURDAY 9 JAN 2016...A COLD FRONT WILL
MOVE THROUGH EARLY THIS MORNING. WINDS HAVE DECREASED BELOW GALE BUT
STEEP SEAS CONTINUE WITH VERY SHORT PERIOD AROUND 9 SECONDS. A
WEAKER FRONT WILL MOVE THROUGH THE WATERS MONDAY, BUT WITH ANOTHER
HEAVY LONG PERIOD WEST SWELL. A STRONG LOW PRESSURE WILL APPROACH
THE WATERS FROM THE WEST TUESDAY. SOUTH WINDS AHEAD OF THIS LOW
COULD APPROACH GALE AGAIN TUESDAY NIGHT. /FB
&&
PREV DISCUSSION... /ISSUED 302 AM PST SAT JAN 9 2016/
DISCUSSION...
SHORT TERM...TODAY THROUGH TUESDAY...A WEAK FRONT IS MOVING ONSHORE
THIS MORNING, AND IS BRINGING SOME LIGHT PRECIPITATION TO THE AREA.
SNOW LEVELS WILL REMAIN AT ABOUT 4000 FEET THROUGHOUT THE AREA, WITH
THE EXCEPTION OF THE MOUNT SHASTA CITY AREA, WHERE SNOW LEVELS WILL
BE ABOUT 500 LOWER DUE TO PRECIPITATION RATES IN THE STRONGER AREA OF
UPSLOPE FLOW. DUE TO THIS, THE WINTER WEATHER ADVISORY FOR THAT AREA
WILL REMAIN IN EFFECT UNTIL LATER THIS MORNING, MOSTLY DUE TO
WEEKEND TRAVEL CONCERNS. A FEW INCHES ARE ALSO EXPECTED IN THE
MOUNTAINS AND ACROSS THE EAST SIDE, BUT AMOUNTS SHOULD NOT APPROACH
ADVISORY CRITERIA.
UPPER LEVEL RIDGING AND SURFACE HIGH PRESSURE WILL BUILD INTO THE
PACIFIC NORTHWEST LATE TONIGHT AND PERSIST THROUGH SUNDAY. LOOK FOR
VALLEY FOG OR LOW STRATUS IN THE WEST SIDE VALLEYS, AND MUCH COLDER
LOW TEMPERATURES EAST OF THE CASCADES, BOTH DUE TO MOSTLY CLEAR
SKIES AND EXCELLENT RADIATIONAL COOLING OVERNIGHT. THE NEXT SYSTEM,
DUE IN LATE SUNDAY NIGHT INTO MONDAY, APPEARS VERY SIMILAR TO THE
ONE TODAY, WEAKENING CONSIDERABLY AS IT MOVES ONSHORE, AND ONLY
PRODUCING LIGHT PRECIPITATION. THE BULK OF THE MOISTURE WITH THIS
FRONT WILL BE CONCENTRATED TO OUR SOUTH, BUT CURRY, JOSEPHINE, AND
WESTERN SISKIYOU COUNTIES SHOULD SEE SOME DECENT PRECIPITATION
AMOUNTS, ALTHOUGH NOTHING LIKE THE LARGER SYSTEMS SEEN BACK IN
DECEMBER.
RIDGING RETURNS LATE MONDAY NIGHT INTO TUESDAY MORNING, AHEAD OF THE
NEXT FRONT DUE IN TUESDAY AFTERNOON. THIS APPEARS TO BE A MORE
CLASSIC WET-SEASON FRONTAL SYSTEM, THAT SHOULD THE MODELS VERIFY,
HAS THE POTENTIAL TO BRING SIGNIFICANT RAINS AND WIND TO SOUTHERN
OREGON AND NORTHERN CALIFORNIA. HOWEVER, THERE IS SOME QUESTION IN
TIMING, AS WELL AS IF THE SYSTEM WILL HOLD TOGETHER SUFFICIENTLY AS
IT MOVES ASHORE AND ENCOUNTERS THE PERSISTENT RIDGE IN PLACE OVER
THE WESTERN US. WILL HOPE FOR BETTER CONFIDENCE IN THESE DETAILS
WITH THE NEXT ROUND OF MODEL RUNS, BUT FOR NOW HAVE TRENDED TOWARDS
A BLEND OF THE GFS AND ECMWF SOLUTIONS AS WE HEAD INTO THE EXTENDED
PERIOD. -BPN
LONG TERM DISCUSSION FROM PREVIOUS ISSUANCE...TUESDAY NIGHT
THROUGH FRIDAY...MODELS SHOW A PERSISTENT PATTERN WITH FRONTS
MOVING INTO THE AREA THROUGH NEXT WEEK. AN UPPER LOW IS FORECAST
TO REMAIN ANCHORED NEAR THE ALEUTIAN ISLANDS WITH A STRONG UPPER
LEVEL JET OVER THE CENTRAL PACIFIC WHILE WEAK RIDGING REMAINS OVER
THE PACNW. SEVERAL LOW PRESSURE SYSTEMS AND FRONTS ARE FORECAST TO
MOVE INTO THE RIDGE AND WEAKEN IT AND BRING PERIODS OF
PRECIPITATION THROUGH NEXT WEEK.
TUESDAY NIGHT INTO WEDNESDAY...MODELS ARE SHOWING GOOD AGREEMENT
WITH A FRONT PUSHING INLAND TUESDAY NIGHT. THIS FRONT IS EXPECTED TO
SPREAD MODERATE PRECIPITATION ACROSS MUCH OF THE AREA WITH SNOW
LEVELS INITIALLY AROUND 5000 FEET TUESDAY NIGHT AND LOWERING TO 4000
FEET DURING THE DAY WEDNESDAY. THE GFS SHOWS A WEAK WARM LAYER ABOVE
THE SURFACE MOVING INTO EASTERN AREAS ON TUESDAY NIGHT WITH
TEMPERATURES NEAR OR BELOW FREEZING AT THE SURFACE IN EASTERN
VALLEYS. THE ECMWF THOUGH INDICATES COLDER TEMPERATURES WITH ONLY SNOW
OVER EASTERN AREAS. IN THE CURRENT FORECAST, HAVE ADDED A SLIGHT
CHANCE FOR FREEZING RAIN TO VALLEYS EAST OF THE CASCADES TUESDAY
NIGHT. CONFIDENCE IS LOW FOR FREEZING RAIN THOUGH AND WILL NEED TO
MONITOR THIS WITH FUTURE MODEL RUNS. A SURFACE LOW IS FORECAST TO
DEVELOP ON THE SOUTHERN END THIS FRONT WITH THE SHORTWAVE TROUGH AND
MOVE INTO SOUTHERN OREGON AND/OR NORTHERN CALIFORNIA LATE WEDNESDAY.
MODELS SHOW VARIABILITY ON THE TRACK AND STRENGTH OF THIS LOW.
OVERALL EXPECT THAT THIS FEATURE ALONG WITH THE SHORTWAVE TROUGH
MOVING INLAND WILL MAY BRING SOME CONTINUED SHOWERS TO THE AREA
THROUGH WEDNESDAY NIGHT.
EXPECT DIMINISHING SHOWERS THURSDAY INTO FRIDAY WITH WEAK RIDGING
BUILDING INTO THE REGION AGAIN. OF NOTE, THE GFS CONTINUES TO SHOW
SOME WEAK DISTURBANCES MOVING INTO THE RIDGE AND BRINGING A SLIGHT
CHANCE FOR LIGHT PRECIPITATION, MAINLY FOR NORTHERN CALIFORNIA AND
FROM THE CASCADES WEST.
FRIDAY NIGHT INTO SATURDAY, MODELS THEN TREND WETTER WITH ANOTHER
FRONT BRINGING ADDITIONAL RAIN AND SNOW INTO THE AREA. THE GFS
REMAINS FASTER THAN THE ECMWF THOUGH ON THE TRACK OF THIS FRONT.
HAVE GONE WITH A BLEND OF THE MODELS FOR THE PRECIPITATION FORECAST
LATE NEXT WEEK. /CC
AVIATION...FOR THE 09/06Z TAF CYCLE...A WARM FRONT MOVING ACROSS
THE REGION THIS EVENING WILL BRING LIGHT WEST SIDE VALLEY RAIN AND
MOUNTAIN AND EAST SIDE LIGHT SNOW. EXPECT MVFR CIGS/VIS ON THE WEST
SIDE OVERNIGHT AND MVFR TO IFR CONDITIONS ON THE EAST SIDE.
MOUNTAINS WILL BE OBSCURED THROUGH THE NIGHT. CIGS AND VIS WILL
IMPROVE TO VFR SATURDAY AFTERNOON. -WRIGHT
MARINE...UPDATED 415 PM PST FRIDAY 8 JAN 2016...A COLD FRONT WILL MOVE
THROUGH TONIGHT WITH GALE FORCE SOUTH WINDS AND VERY STEEP SEAS
EXPECTED BEYOND 5NM FROM SHORE. WITH AN OFFSHORE COMPONENT TO THE WINDS
THIS EVENING, AREAS IN CLOSER TO SHORE LIKELY ONLY HAVE CONDITIONS
HAZARDOUS TO SMALL CRAFT. BUT EVEN THOSE AREAS PROBABLY HAVE VERY STEEP
SEAS FOR A WHILE SATURDAY MORNING. A WEAKER FRONT WILL MOVE THROUGH THE
WATERS MONDAY, BUT WITH ANOTHER HEAVY LONG PERIOD WEST SWELL. A STRONG
COLD FRONT WILL APPROACH THE WATERS TUESDAY NIGHT AND MOVE ONSHORE
WEDNESDAY. SPILDE
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...
CA...WINTER WEATHER ADVISORY UNTIL 10 AM PST THIS MORNING FOR CAZ082.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 10 AM PST SUNDAY
FOR PZZ350-356.
HAZARDOUS SEAS WARNING UNTIL 10 AM PST THIS MORNING FOR
PZZ350-356-370-376.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 PM PST SUNDAY
FOR PZZ370-376.
$$
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
204 AM EST SAT JAN 9 2016
.SYNOPSIS...
A LIGHT COATING OF FREEZING RAIN IS POSSIBLE OVER THE MOUNTAINS
TONIGHT AS WARMER AIR SPREADS ACROSS THE REGION. A STRONG LOW
PRESSURE SYSTEM WILL TAKE A PATH WEST AND NORTH OF PENNSYLVANIA
SATURDAY NIGHT INTO EARLY SUNDAY. AN UPPER LEVEL TROUGH WILL THEN
PIVOT THROUGH THE NORTHEAST CONUS DURING THE FIRST HALF OF NEXT
WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
REGIONAL RADAR LOOP AND NEAR TERM MDL DATA SUPPORT OCNL LGT RAIN
CONTINUING ACROSS NORTHWEST PA THRU DAWN IN ASSOC WITH WEAK
SHORTWAVE LIFTING NE ACROSS THE GRT LKS. WEAKER LG SCALE FORCING
ACROSS THE SE HALF OF THE STATE SHOULD RESULT IN LITTLE MORE THAN
DRIZZLE IN THAT AREA.
07Z MESONET SFC OBS INDICATE NEARLY THE ENTIRE AREA IS ABV
FREEZING. HOWEVER...WILL HOLD ONTO THE ADVISORY FOR A FEW MORE
HOURS TO ACCOUNT FOR POSSIBLE ICY SPOTS WHERE GROUND TEMPS REMAIN
BLW FREEZING. NCAR MESO ENSEMBLE OUTPUT SUGGESTS THE BEST CHC OF
ADDITIONAL ICING BTWN 07Z-10Z WILL BE OVR THE MTNS NORTH OF KIPT.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM TODAY/...
NO SIG RAIN EXPECTED LATER TODAY...AS UPPER LVL RIDGING BUILDS
OVR THE REGION. HOWEVER...A MOIST SERLY FLOW WILL YIELD LINGERING
LOW CLOUDS AND SPOTTY DRIZZLE. SUPERBLEND INDICATES TEMPS ONLY
SLOWLY RISING TO BTWN 40-45F.
&&
.LONG TERM /TONIGHT THROUGH FRIDAY/...
A POTENT SOUTHERN STREAM SHORTWAVE AND ASSOC SFC LOW WILL TRACK
WEST OF PA SAT NIGHT/EARLY SUNDAY. A PERIOD OF STEADY/MODERATE
RAIN IS EXPECTED SATURDAY NIGHT INTO SUNDAY MORNING AS ANOMALOUS
SERLY LL JET/PWAT PLUME LIFTS THRU. GEFS MFLUX VALUES TOP OUT ARND
3SD ABV CLIMO EARLY SUN AM. MDL CONSENSUS RAINFALL AMOUNTS ARE
CLOSE TO 1 INCH OVER MUCH OF CENTRAL PA BY THE TIME IT TAPERS OFF
LATE SUNDAY MORNING.
ABOVE NORMAL TEMPERATURES EXPECTED SUNDAY...AS THE REGION BRIEFLY
BREAKS INTO WARM SECTOR SOUTH OF SFC LOW. HOWEVER...MUCH COLDER
AIR WILL ARRIVE VIA GUSTY WEST WINDS BEHIND THE COLD FRONT LATER
SUNDAY INTO EARLY MONDAY. A BAND OF FRONTAL RAIN SHOWERS WILL
LIKELY END AS A PERIOD OF SNOW SHOWERS OVER THE ALLEGHENIES SUNDAY
PM.
A PERSISTENT COLD WESTERLY FLOW PATTERN SHOULD SUPPORT PERIODS OF
LAKE EFFECT AND OROGRAPHIC SNOW SHOWERS THROUGH THE MIDDLE OF NEXT
WEEK. SNOW ACCUMULATION IS PROBABLE DOWNWIND OF LAKE ERIE AND OVER
THE RIDGES IN SOUTHWEST PENNSYLVANIA. TEMPERATURES SHOULD AVERAGE
BELOW NORMAL WITH SINGLE DIGITS WIND CHILLS LIKELY OVER THE
ALLEGHENIES.
&&
.AVIATION /07Z SATURDAY THROUGH WEDNESDAY/...
AS THE SYSTEM MOVES THROUGH CURRENTLY THE HEAVIEST SHOWERS ARE
MOVING INTO THE NORTHEAST...WITH LIGHT RAIN ACROSS CENTRAL PA.
TEMPERATURES HAVE INCREASED...WITH SFC TEMPS JUST ABOVE FREEZING.
DEWPOINTS REMAIN AT OR SLIGHTLY ABOVE FREEZING SO THERE STILL
REMAINS A PROBABILITY OF FREEZING RAIN OVERNIGHT. THOUGH THIS
PROBABILITY IS LESS CONSIDERING THE FLOW HAS SHIFTED TO THE
SOUTHWEST. LATEST HRRR SHOWS TEMPERATURES SLOWLY WARMING
OVERNIGHT.
HOWEVER THE COPIOUS AMOUNTS OF LOW LEVEL MOISTURE HAVE ALLOWED FOR
IFR AND LOWER CIGS TO CONTINUE THROUGH OUT THE CENTRAL AND WESTERN
TAF SITES. AS THE PRECIP MOVES LIGHTENS AND ENDS AS THE NIGHT
CONTINUES...VSBYS COULD IMPROVE...HOWEVER THE LOW STRATOCU SHOULD
REMAIN IN PLACE THROUGH THE EARLY MORNING HOURS AND SREF AND NAM
SHOWING IT SPREADING EAST. THE LOW STRATOCU WILL KEEP PERSISTENT IFR
CIGS ACROSS THE WESTERN HALF OF CENTRAL PENNSYLVANIA THROUGH THE
MORNING AND INTO THE EARLY AFTERNOON HOURS. ANY CIGS WILL LIFT
BRIEFLY IN THE SOUTHEAST TOMORROW AFTERNOON AND INTO THE EARLY
EVENING. HOWEVER. AREAS TO THE EAST...THOUGH SEEING MVFR CIGS AND
LIGHT RAIN...REMAIN ABOVE FREEZING. WINDS OUT WEST HAVE SHIFTED TO
THE SOUTH EAST...WITH CALM WINDS THROUGH CENTRAL TAF SITES...AND
EASTERLY WINDS OUT EAST. AS THE SHOWERS CONTINUE TO MOVE TO THE
NORTHEAST...EXPECT CIG AND VSBYS TO DEGRADE AT IPT AND WINDS TO
GRADUALLY SHIFT TO THE SOUTH EAST ACROSS THE REGION OVERNIGHT.
BEHIND THE FIRST SUBSTANTIAL ROUND OF FREEZING PRECIPITATION...ANY
PRECIPITATION WILL BE LIGHT. EXPECT REDUCING CIGS AND VSBYS TO
PERSIST WELL INTO TOMORROW BEFORE IMPROVING TOMORROW AFTERNOON
BRIEFLY...AND THEN DEGRADING AGAIN TOMORROW EVENING.
RESTRICTIONS WILL PERSIST THROUGH THE WEEKEND UNTIL NEXT SYSTEM
MOVES THROUGH ON SUNDAY...WHEN FLOW WILL TURN WESTERLY /AND BE
QUITE STRONG/ WITH RESTRICTIONS BECOMING CONFINED TO WESTERN
HIGHER TERRAIN.
LATE TOMORROW NIGHTS SYSTEM COULD SEE SOME LOW LEVEL WIND SHEAR
AT THE WESTERN TAF SITES AFTER 06Z SUNDAY.
OUTLOOK...
SAT...LOW CIGS CONTINUE. AREAS OF DRIZZLE POSSIBLE.
SAT NIGHT...LOW CIGS. AREAS OF RAIN. LLWS LIKELY.
SUN...AM RAIN/LOW CIGS POSSIBLE. TURNING QUITE WINDY WITH PM
SHSN/BRIEF VIS REDUCTIONS POSSIBLE KBFD/KJST. WESTERLY WIND GUSTS
ACROSS CENTRAL AND WRN PENN POSSIBLY TOPPING 40 KTS AT TIMES.
MON...A FEW LOCALIZED BANDS OF LOW CIGS AND VSBYS IN SNOW SHOWERS
ACROSS THE LAUREL HIGHLANDS AND NW MTNS. OTHERWISE...QUITE BREEZY
WITH NO WIDESPREAD SIG WX RESTRICTIONS EXPECTED.
TUE...CIG REDUCTIONS LIKELY NW HALF IN SNOW SHOWERS. VFR
ELSEWHERE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
FREEZING RAIN ADVISORY UNTIL 5 AM EST EARLY THIS MORNING FOR
PAZ005-006-010>012-017>019-024>028-033>035-037-041-042-045-046-
049-050.
&&
$$
SYNOPSIS...DANGELO
NEAR TERM...FITZGERALD
SHORT TERM...FITZGERALD
LONG TERM...FITZGERALD/GARTNER
AVIATION...CERU/RXR
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1209 AM EST SAT JAN 9 2016
.SYNOPSIS...
A LIGHT COATING OF FREEZING RAIN IS POSSIBLE OVER THE MOUNTAINS
TONIGHT AS WARMER AIR SPREADS ACROSS THE REGION. A STRONG LOW
PRESSURE SYSTEM WILL TAKE A PATH WEST AND NORTH OF PENNSYLVANIA
SATURDAY NIGHT INTO EARLY SUNDAY. AN UPPER LEVEL TROUGH WILL THEN
PIVOT THROUGH THE NORTHEAST CONUS DURING THE FIRST HALF OF NEXT
WEEK.
&&
.NEAR TERM /THROUGH SATURDAY/...
10 PM UPDATE...
A COUPLE OF MORE WAVES OF SHOWERS /SCT COVG/ CONTINUE TO MOVE
INTO THE AREA FROM THE SW. MANY OF THE POPULATED AREAS ARE ABOVE
FREEZING. HOWEVER...THE HIGH ELEVATIONS IN THE
LAURELS...ALLEGHENIES AND NORTHEAST MOUNTAINS ARE AOB FREEZING.
WHILE IT IS STILL EXPECTED TO WARM UP A DEG OR TWO
OVERNIGHT...LATEST HRRR AND RAP SFC TEMPS REMAIN BELOW FZG IN THE
HIGHER ELEVS THRU 10Z. LWX HAS EXTENDED THEIR ADVY INTO THE
MORNING...AND HAVE WE HAVE CHOSEN TO EXTEND THE ADVY SEGMENT WHICH
COVERS THE MAJORITY OF CENTRAL PA THROUGH 10Z AS WELL. THUS...ALL
THE FZRA ADVY NOW GOES UNTIL 10Z.
PREV...
CLOUDS WILL CONTINUE TO THICKEN ACROSS THE REGION AHEAD OF A WARM
FRONT THAT WILL BRING SOME LIGHT SHOWERS AND FREEZING RAIN THIS
EVENING. TEMPERATURES ARE CURRENTLY IN THE UPPER 30S ACROSS THE
SOUTHERN PIEDMONT AND SUSQUEHANNA VALLEY. ACROSS THE CENTRAL AND
NORTHERN MOUNTAINS TEMPERATURES HAVE STRUGGLED TO RISE TODAY AND
ARE CURRENTLY IN THE UPPER 20S. THIS HAS LED TO A CONCERN FOR
FREEZING RAIN THIS EVENING...AND WE HAVE ISSUED A FREEZING RAIN
ADVISORY FOR THESE AREAS. HIGH TEMPERATURES IN THE MOUNTAINS WILL
STRUGGLE TO REACH THE FREEZING POINT AND WILL QUICKLY COOL WHEN
PRECIPITATION ARRIVES FROM EVAPORATIONAL COOLING DUE TO THE LOW
DEW POINTS FOR THESE LOCATIONS.
THE OTHER STORY TODAY HAS BEEN THE PERSISTENT FOG AND MIST OVER
THE EXTREME SOUTHERN SUSQUEHANNA VALLEY. EVERYWHERE BUT YORK HAS
LIFTED ABOVE A MILE VISIBILITY BUT THE FOG WILL REASSERT ITSELF
LATER THIS EVENING WHEN IT STARTS RAINING.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH 6 PM SATURDAY/...
RAIN SHOULD BEGIN TO FALL AROUND 7 PM OVER THE LAUREL HIGHLANDS
AND NORTHWEST MOUNTAINS AND WILL SPREAD EASTWARD FROM THERE. OVER
THE MOUNTAINS THE RAIN WILL FALL AS FREEZING RAIN AND WILL ACCUMULATE
UP TO A FEW HUNDREDTHS OF AN INCH BEFORE TEMPERATURES WARM ABOVE
FREEZING. FARTHER EAST...ESPECIALLY
CLINTON...POTTER...TIOGA...LYCOMING...AND SULLIVAN
COUNTIES...TEMPERATURES MAY NOT RISE ABOVE FREEZING DURING THE
LIGHT RAIN AND ICE COULD ACCUMULATE BETWEEN A TENTH AND TWO
TENTHS.
NO SIG RAIN EXPECTED DURING SATURDAY...AS UPPER LVL RIDGING
BUILDS OVR THE REGION. HOWEVER...A MOIST SERLY FLOW WILL YIELD
LINGERING LOW CLOUDS AND SPOTTY DRIZZLE. SUPERBLEND INDICATES
TEMPS ONLY SLOWLY RISING TO BTWN 40-45F.
&&
.LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/...
A POTENT SOUTHERN STREAM SHORTWAVE AND ASSOC SFC LOW WILL TRACK
WEST OF PA SAT NIGHT/EARLY SUNDAY. A PERIOD OF STEADY/MODERATE
RAIN IS EXPECTED SATURDAY NIGHT INTO SUNDAY MORNING AS ANOMALOUS
SERLY LL JET/PWAT PLUME LIFTS THRU. GEFS MFLUX VALUES TOP OUT ARND
3SD ABV CLIMO EARLY SUN AM. MDL CONSENSUS RAINFALL AMOUNTS ARE
CLOSE TO 1 INCH OVER MUCH OF CENTRAL PA BY THE TIME IT TAPERS OFF
LATE SUNDAY MORNING.
ABOVE NORMAL TEMPERATURES EXPECTED SUNDAY...AS THE REGION BRIEFLY
BREAKS INTO WARM SECTOR SOUTH OF SFC LOW. HOWEVER...MUCH COLDER
AIR WILL ARRIVE VIA GUSTY WEST WINDS BEHIND THE COLD FRONT LATER
SUNDAY INTO EARLY MONDAY. A BAND OF FRONTAL RAIN SHOWERS WILL
LIKELY END AS A PERIOD OF SNOW SHOWERS OVER THE ALLEGHENIES SUNDAY
PM.
A PERSISTENT COLD WESTERLY FLOW PATTERN SHOULD SUPPORT PERIODS OF
LAKE EFFECT AND OROGRAPHIC SNOW SHOWERS THROUGH THE MIDDLE OF NEXT
WEEK. SNOW ACCUMULATION IS PROBABLE DOWNWIND OF LAKE ERIE AND OVER
THE RIDGES IN SOUTHWEST PENNSYLVANIA. TEMPERATURES SHOULD AVERAGE
BELOW NORMAL WITH SINGLE DIGITS WIND CHILLS LIKELY OVER THE
ALLEGHENIES.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
AS THE SYSTEM MOVES THROUGH CURRENTLY THE HEAVIEST SHOWERS ARE
MOVING INTO THE NORTHEAST...WITH LIGHT RAIN ACROSS CENTRAL PA.
TEMPERATURES HAVE INCREASED...WITH SFC TEMPS JUST ABOVE FREEZING.
DEWPOINTS REMAIN AT OR SLIGHTLY ABOVE FREEZING SO THERE STILL
REMAINS A PROBABILITY OF FREEZING RAIN OVERNIGHT. THOUGH THIS
PROBABILITY IS LESS CONSIDERING THE FLOW HAS SHIFTED TO THE
SOUTHWEST. LATEST HRRR SHOWS TEMPERATURES SLOWLY WARMING
OVERNIGHT.
HOWEVER THE COPIOUS AMOUNTS OF LOW LEVEL MOISTURE HAVE ALLOWED FOR
IFR AND LOWER CIGS TO CONTINUE THROUGH OUT THE CENTRAL AND WESTERN
TAF SITES. AS THE PRECIP MOVES LIGHTENS AND ENDS AS THE NIGHT
CONTINUES...VSBYS COULD IMPROVE...HOWEVER THE LOW STRATOCU SHOULD
REMAIN IN PLACE THROUGH THE EARLY MORNING HOURS AND SREF AND NAM
SHOWING IT SPREADING EAST. THE LOW STRATOCU WILL KEEP PERSISTENT IFR
CIGS ACROSS THE WESTERN HALF OF CENTRAL PENNSYLVANIA THROUGH THE
MORNING AND INTO THE EARLY AFTERNOON HOURS. ANY CIGS WILL LIFT
BRIEFLY IN THE SOUTHEAST TOMORROW AFTERNOON AND INTO THE EARLY
EVENING. HOWEVER. AREAS TO THE EAST...THOUGH SEEING MVFR CIGS AND
LIGHT RAIN...REMAIN ABOVE FREEZING. WINDS OUT WEST HAVE SHIFTED TO
THE SOUTH EAST...WITH CALM WINDS THROUGH CENTRAL TAF SITES...AND
EASTERLY WINDS OUT EAST. AS THE SHOWERS CONTINUE TO MOVE TO THE
NORTHEAST...EXPECT CIG AND VSBYS TO DEGRADE AT IPT AND WINDS TO
GRADUALLY SHIFT TO THE SOUTH EAST ACROSS THE REGION OVERNIGHT.
BEHIND THE FIRST SUBSTANTIAL ROUND OF FREEZING PRECIPITATION...ANY
PRECIPITATION WILL BE LIGHT. EXPECT REDUCING CIGS AND VSBYS TO
PERSIST WELL INTO TOMORROW BEFORE IMPROVING TOMORROW AFTERNOON
BRIEFLY...AND THEN DEGRADING AGAIN TOMORROW EVENING.
RESTRICTIONS WILL PERSIST THROUGH THE WEEKEND UNTIL NEXT SYSTEM
MOVES THROUGH ON SUNDAY...WHEN FLOW WILL TURN WESTERLY /AND BE
QUITE STRONG/ WITH RESTRICTIONS BECOMING CONFINED TO WESTERN
HIGHER TERRAIN.
LATE TOMORROW NIGHTS SYSTEM COULD SEE SOME LOW LEVEL WIND SHEAR
AT THE WESTERN TAF SITES AFTER 06Z SUNDAY.
OUTLOOK...
SAT...LOW CIGS CONTINUE. AREAS OF DRIZZLE POSSIBLE.
SAT NIGHT...LOW CIGS. AREAS OF RAIN. LLWS LIKELY.
SUN...AM RAIN/LOW CIGS POSSIBLE. TURNING QUITE WINDY WITH PM
SHSN/BRIEF VIS REDUCTIONS POSSIBLE KBFD/KJST. WESTERLY WIND GUSTS
ACROSS CENTRAL AND WRN PENN POSSIBLY TOPPING 40 KTS AT TIMES.
MON...A FEW LOCALIZED BANDS OF LOW CIGS AND VSBYS IN SNOW SHOWERS
ACROSS THE LAUREL HIGHLANDS AND NW MTNS. OTHERWISE...QUITE BREEZY
WITH NO WIDESPREAD SIG WX RESTRICTIONS EXPECTED.
TUE...CIG REDUCTIONS LIKELY NW HALF IN SNOW SHOWERS. VFR
ELSEWHERE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
FREEZING RAIN ADVISORY UNTIL 5 AM EST SATURDAY FOR PAZ005-006-
010>012-017>019-024>028-033>035-037-041-042-045-046-049-050.
&&
$$
SYNOPSIS...DANGELO
NEAR TERM...DANGELO
SHORT TERM...FITZGERALD
LONG TERM...FITZGERALD/GARTNER
AVIATION...CERU/RXR
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1143 AM CST SAT JAN 9 2016
.UPDATE...
FOR 18Z AVIATION DISCUSSION.
&&
.DISCUSSION...
A FEW LIGHT SHOWERS AND DRIZZLE ARE ONGOING ACROSS THE WESTERN
PORTIONS OF MIDDLE TN AT UPDATE TIME THIS MORNING. SHOWER COVERAGE
AND INTENSITY WILL PICK UP THROUGH THE AFTERNOON HOURS AS THE LOW
PRESSURE CENTER OF THIS CURRENT SYSTEM PULLS NEWD OUT OF NW
MISSISSIPPI/SE ARKANSAS AND TRAVERSES WEST TN. THE QUESTIONS WILL
LIE WITH HOW MUCH THUNDERSTORM COVERAGE WILL THERE BE. AS THE LOW
MOVES CLOSER...A POCKET OF DRY AIR WILL MOVE INTO THE MID-STATE.
EVIDENT ALREADY IN THE VISIBLE SATELLITE IMAGERY OVER NORTHERN
MS...SOME SUNSHINE MAY VERY WELL PEEK OUT EARLY THIS AFTERNOON.
THIS IS THE INGREDIENT NECESSARY TO WARM US UP A LITTLE AND PROVIDE
SOME LIMITED CAPE VALUES /250-500 J/KG/ OVER THE SOUTHERN HALF OF
THE MID-STATE. IF WE CAN GET ENOUGH INSTABILITY TO FIRE A FEW
THUNDERSTORMS...FORECAST SOUNDINGS SUGGEST THAT THE COLD AIR
ALOFT WILL PROVIDE MID-LEVEL LAPSE RATES SHARP ENOUGH FOR SMALL
HAIL DEVELOPMENT AND EVEN A STRONG WIND GUST OR TWO. THE LATEST
COUPLE RUNS OF THE HRRR IS IN DECENT AGREEMENT WITH THIS SOLUTION
AS IT CONTINUES TO BRING A BROKEN LINE OF THUNDERSTORMS NEWD INTO
OUR SOUTHERN COUNTIES LATE THIS AFTERNOON. WILL HIGHLIGHT THIS
STRONG THUNDERSTORM POTENTIAL IN THE HAZARDOUS WEATHER OUTLOOK
THROUGH THE EARLY EVENING HOURS. THE GOOD NEWS IS AFTER THE SUN
GOES DOWN WE`LL LOSE THE INSTABILITY AND ANY STORMS THAT HAVE
DEVELOPED SHOULD DISSIPATE LEAVING ONLY MODERATE SHOWERS FOR OUR
EASTERN COUNTIES THIS EVENING.
THE BIGGER STORY WILL BE THE PUSH OF COLD AIR BEHIND THIS SYSTEM
AND IT MATCHING UP WITH LINGERING ATMOSPHERIC MOISTURE. MODELS ARE
IN DECENT AGREEMENT ABOUT MIDDLE TN SEEING ITS FIRST SNOWFALL OF
THIS WINTER AND OF 2016. WE`RE WORKING OUT THE DETAILS OF WHAT TO
EXPECT AND THIS WILL BE THE FOCUS OF THIS AFTERNOON`S FULL
FORECAST PACKAGE.
&&
.AVIATION...
18Z TAF DISCUSSION.
DIVERSE TAF CYCLE. WILL RANGE FROM LIGHT TO MODERATE RAINS THIS
AFTERNOON AND EVENING TO A CHANGEOVER TO LIGHT SNOW AFTER 06Z AS
COLD AIR MOVES IN. MVFR CIGS ARE EXPECTED TO CONTINUE THIS
AFTERNOON AND BEGIN TO FALL INTO IFR THIS EVENING. VIS WILL
FLUCTUATE BASED ON RAIN INTENSITIES.
WINDS WILL BE BREEZY OUT OF THE SOUTHEAST THEN VEER TO THE NW AS
THE COLDER AIR INTRUDES INTO THE MID-STATE TONIGHT. GUSTS OF
15-18 KTS ARE POSSIBLE THROUGHOUT THE CYCLE.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM/AVIATION........UNGER
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1110 AM CST SAT JAN 9 2016
.UPDATE...
FOR MORNING DISCUSSION.
&&
.DISCUSSION...
A FEW LIGHT SHOWERS AND DRIZZLE ARE ONGOING ACROSS THE WESTERN
PORTIONS OF MIDDLE TN AT UPDATE TIME THIS MORNING. SHOWER COVERAGE
AND INTENSITY WILL PICK UP THROUGH THE AFTERNOON HOURS AS THE LOW
PRESSURE CENTER OF THIS CURRENT SYSTEM PULLS NEWD OUT OF NW
MISSISSIPPI/SE ARKANSAS AND TRAVERSES WEST TN. THE QUESTIONS WILL
LIE WITH HOW MUCH THUNDERSTORM COVERAGE WILL THERE BE. AS THE LOW
MOVES CLOSER...A POCKET OF DRY AIR WILL MOVE INTO THE MID-STATE.
EVIDENT ALREADY IN THE VISIBLE SATELLITE IMAGERY OVER NORTHERN
MS...SOME SUNSHINE MAY VERY WELL PEEK OUT EARLY THIS AFTERNOON.
THIS IS THE INGREDIENT NECESSARY TO WARM US UP A LITTLE AND PROVIDE
SOME LIMITED CAPE VALUES /250-500 J/KG/ OVER THE SOUTHERN HALF OF
THE MID-STATE. IF WE CAN GET ENOUGH INSTABILITY TO FIRE A FEW
THUNDERSTORMS...FORECAST SOUNDINGS SUGGEST THAT THE COLD AIR
ALOFT WILL PROVIDE MID-LEVEL LAPSE RATES SHARP ENOUGH FOR SMALL
HAIL DEVELOPMENT AND EVEN A STRONG WIND GUST OR TWO. THE LATEST
COUPLE RUNS OF THE HRRR IS IN DECENT AGREEMENT WITH THIS SOLUTION
AS IT CONTINUES TO BRING A BROKEN LINE OF THUNDERSTORMS NEWD INTO
OUR SOUTHERN COUNTIES LATE THIS AFTERNOON. WILL HIGHLIGHT THIS
STRONG THUNDERSTORM POTENTIAL IN THE HAZARDOUS WEATHER OUTLOOK
THROUGH THE EARLY EVENING HOURS. THE GOOD NEWS IS AFTER THE SUN
GOES DOWN WE`LL LOSE THE INSTABILITY AND ANY STORMS THAT HAVE
DEVELOPED SHOULD DISSIPATE LEAVING ONLY MODERATE SHOWERS FOR OUR
EASTERN COUNTIES THIS EVENING.
THE BIGGER STORY WILL BE THE PUSH OF COLD AIR BEHIND THIS SYSTEM
AND IT MATCHING UP WITH LINGERING ATMOSPHERIC MOISTURE. MODELS ARE
IN DECENT AGREEMENT ABOUT MIDDLE TN SEEING ITS FIRST SNOWFALL OF
THIS WINTER AND OF 2016. WE`RE WORKING OUT THE DETAILS OF WHAT TO
EXPECT AND THIS WILL BE THE FOCUS OF THIS AFTERNOON`S FULL
FORECAST PACKAGE.
&&
.AVIATION...
12Z TAF DISCUSSION.
NUMEROUS SHOWERS ARE EXPECTED TO SPREAD IN FROM THE WEST TODAY,
BEGINNING AT CKV AND BNA AROUND 15Z, AND AT CSV AROUND 21Z. MVFR
CONDITIONS AT CKV WILL DETERIORATE TO IFR BY 18Z, THEN CONTINUE
IFR FOR THE REST OF THE FORECAST PERIOD. MVFR CONDITIONS WILL
DEVELOP AT BNA AND CSV BY 15Z, THEN DETERIORATE TO IFR BY LATE
AFTERNOON OR EVENING. A FEW THUNDERSTORMS ARE ALSO POSSIBLE TODAY,
AHEAD OF AN APPROACHING COLD FRONT. FOLLOWING PASSAGE OF THE COLD
FRONT TONIGHT, -SHRA WILL CHANGE TO -RASN AND -SN.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM/AVIATION........UNGER
LONG TERM..................13
AREA FORECAST DISCUSSION...UPDATED
NWS MORRISTOWN TN
1038 AM EST SAT JAN 9 2016
.DISCUSSION...
LATEST HRRR AND RAP REFLECTIVITY SIMIULATIONS SHOW A LATER ARRIVAL
OF RAIN INTO THE AREA THAN PREVIOUS RUNS...AND THIS LINES UP WELL
WITH CURRENT RADAR TRENDS. PRECIP NEAR THE MS/AL STATE LINE WILL
NOT ARRIVE UNTIL AFTER 18Z...SO WILL ADJUST POPS TO DELAY ANY
PRECIP CHANCES UNTIL AFTER THIS TIME...AND LOWER POPS TODAY DOWN
INTO THE LIKELY RANGE. A SLIGHT DOWNWARD ADJUSTMENT OF TEMPERATURES
WILL BE MADE AS WELL. WITH CLOUDS SPREADING FROM SOUTH TO
NORTH...THE WARMEST TEMPS TODAY WILL BE IN NORTHERN AREAS.
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
DGS
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1141 PM CST FRI JAN 8 2016
.AVIATION...
THE LATEST HRRR BRINGS A FEW SHOWERS ACROSS KCLL/KUTS OVERNIGHT
BUT THE DEEPER CONVECTION IS WELL EAST OF AREA TAF SITES. LOW CIGS
AND AREAS OF FOG DEVELOPING IN THE WAKE OF THE CONVECTION WILL
CONTINUE TO HAMPER AVIATION INTERESTS OVERNIGHT. NOT MUCH
CONFIDENCE IN HOW THINGS EVENTUALLY PLAY OUT AS DRIER AIR TO THE
WEST SHOULD FILTER IN TO THE REGION OVERNIGHT. THERE COULD BE SOME
BRIEF CLEARING BEFORE WRAP AROUND CLOUDS BRING MVFR CIGS BACK TO
AREA TAF SITES FOR MUCH OF SATURDAY. WINDS WILL BE CONSIDERABLY
STRONGER ON SATURDAY AND ADDED A GUST GROUP. 43
&&
.PREV DISCUSSION... /ISSUED 923 PM CST FRI JAN 8 2016/
UPDATE...
QUICK FORECAST UPDATE TO DROP THE WESTERN TWO THIRDS OF THE
FORECAST AREA FROM SEVERE THUNDERSTORM WATCH 1 AS MAJORITY OF
CONVECTION HAS EXITED THE FORECAST AREA. HAVE ALSO ISSUED A
SHORT-FUSED DENSE FOG ADVISORY FOR THE WESTERN COUNTIES AS
VISIBILITIES HAVE DROPPED TO LESS THAN ONE MILE IN MANY LOCATIONS.
MAY POSSIBLY SEE DENSE FOG DEVELOP IN AND AROUND THE HOUSTON METRO
AS WELL... AND WILL CONTINUE TO MONITOR FOR POSSIBLE EASTWARD
EXPANSION OF THE ADVISORY. WINDS SHIFTING TO THE WEST/NORTHWEST
AHEAD OF AN APPROACHING COLD FRONT TONIGHT WILL HELP DISSIPATE
THE DENSE FOG THAT DEVELOPS... BUT GIVEN UNCERTAINTY ON TIMING THE
DENSE FOG ADVISORY MAY ALSO NEED TO BE EXTENDED IN TIME.
HUFFMAN
PREV DISCUSSION... /ISSUED 311 PM CST FRI JAN 8 2016/
DISCUSSION...
STARTING TO SEE AN INCREASE OF SHRA/TSRA ALONG AND NEAR THE UPPER
TX COAST THIS AFTN AS THE WARM FRONT (OR POSSIBLY A WEAK SFC LOW)
BEGINS TO DEVELOP/MOVE INLAND. RAIN CHANCES WILL CONTINUE TO INCREASE
THIS EVENING WITH THE APPROACH AND PASSAGE OF A STRONG UPPR LEVEL
DISTURBANCE FROM THE WEST. THERE IS A POSSIBILITY OF STRONG TO
SEVERE TSRA WITH THIS FEATURE GIVEN THE VERY STEEP LAPSE RATES AND
DYNAMIC JET STRUCTURE FOR THIS EVENING. HOWEVER..LIMITED DAYTIME
HEATING ALONG WITH A VERY DRY AIRMASS OVER SE TX ARE SOME OF THE
MAIN OBSTACLES TO OVERCOME FOR THESE STORMS TO DEVELOP. SPC`S DAY
1 OUTLOOK HAS MORE DETAILS.
THE PASSAGE OF THE STORM SYSTEM/UPPER TROF THIS EVENING WILL ALSO
DRAG A STRONG COLD FRONT ACROSS SE TX OVERNIGHT AND EARLY SAT
MORNING. COLDER/CLEARING FOR THE REST OF THE WEEKEND AS WINDS
ALOFT BECOME MORE NWLY WITH TIME. HOWEVER...AS IT HAS BEEN THE
CASE MORE OFTEN THAN NOT THIS SEASON...THE RIDGING WITH WILL BE
SHORT LIVED AS WE SEE THE RETURN OF THE SUBTROPICAL JET OVER THE
STATE WITH ANOTHER UPPER TROF DIGGING INTO NRN MEXICO. AND THEN BY
MON (WITH THE SFC HIGH MOVING OFF TO THE E/NE) WE SHOULD BEGIN TO
SEE THE RETURN OF SOME LOW POPS (COASTAL WATERS/SW PARTS OF THE
AREA)...BEFORE POPS SPREAD FURTHER INLAND (LATE WEDS/THUR) AS THE
UPPER TROF MOVES IN FROM THE WEST. 41
MARINE...
PATCHY AREAS OF DENSE SEA FOG WILL REMAIN A POSSIBILITY UNTIL 1-3AM
UNTIL A PREFRONTAL TROUGH PUSHES THRU THE WATERS. AHEAD OF THIS TROF...
WILL PROBABLY SEE SOME SCT SHOWERS/STORMS DEVELOP IN THE WATERS AS
UPPER LEVEL CONDITIONS BECOME MORE FAVORABLE. MAY SEE SOME ISOLATED
STRONGER CELLS CAPABLE OF PRODUCING WATERSPOUTS AND POSSIBLY GUSTY
WINDS. THREAT DIMINISHES AFTER MIDNIGHT ONCE WE SEE A WRLY WIND SHIFT.
COLD FRONT ITSELF WILL MOVE INTO THE AREA EARLY SAT MORNING. WINDS WILL
BECOME MORE NWRLY AND INCREASE TO CAUTION AND ADVSY CRITERIA. WINDS/SEAS
BEGIN DIMINISHING SUNDAY THEN GRADUALLY VEER TO THE NE/E INTO THE MIDWEEK
TIME PERIOD. 47
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 46 56 33 48 31 / 40 10 0 0 10
HOUSTON (IAH) 52 61 36 50 33 / 70 10 0 0 10
GALVESTON (GLS) 55 62 40 49 42 / 60 10 0 0 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...DENSE FOG ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR THE FOLLOWING
ZONES: AUSTIN...BRAZORIA...BRAZOS...BURLESON...COLORADO...
FORT BEND...GRIMES...JACKSON...MATAGORDA...WALLER...
WASHINGTON...WHARTON.
GM...NONE.
&&
$$
DISCUSSION...14
AVIATION/MARINE...43
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
503 AM MST SAT JAN 9 2016
.SHORT TERM...(TODAY THROUGH MONDAY NIGHT)
ISSUED AT 300 AM MST SAT JAN 9 2016
STILL GETTING VERY LIGHT SNOW OR FLURRIES IN AREAS ALONG
INTERSTATE 80...HOWEVER VISIBILITY IS MOSTLY ABOVE 3SM AND
ACCUMULATIONS ARE MINIMAL. THESE SNOW SHOWERS SHOULD GRADUALLY
DIMINISH THROUGH THE MORNING AS THE WEAK LIFT/SATURATION IN THE
700-500MB LAYER DEPARTS THE AREA. TEMPS WILL BE COLD TODAY WITH
MOST LOCATIONS STRUGGLING TO GET OUT OF THE LOW 20S (AROUND 15
DEGREES BELOW NORMAL). KEPT CHANCE POPS GOING FOR THE SIERRA
MADRE/SNOWY RANGES THROUGH THE EARLY EVENING HOWEVER ACCUMULATIONS
WILL BE LIGHT. NORTHWESTERLY FLOW ALOFT WILL REMAIN IN PLACE
THROUGH MONDAY WITH A CONTINUATION OF THE BELOW NORMAL
TEMPS...ALTHOUGH SOME PLACES WILL WARM TO AROUND FREEZING BY
MONDAY.
WILL SEE BREEZY-TO-WINDY CONDITIONS DEVELOP ACROSS SOUTHEAST WY
BY SUNDAY NIGHT INTO MONDAY AS PRESSURE FALLS OCCUR OVER
NEBRASKA/SOUTH DAKOTA AHEAD OF A SOUTHWARD-MOVING SHORTWAVE. THE
850MB CAG-CPR GRADIENT WILL INCREASE TO 45-50 METERS BY LATE
SUNDAY NIGHT SO WILL DEFINITELY SEE AN INCREASE IN WEST WINDS
ESPECIALLY IN THE WIND PRONE AREAS. WITH THE RECENT
SNOWFALL...COULD SEE SOME PATCHY BLOWING SNOW IN ARLINGTON AND
THE SOUTHERN LARAMIE RANGE. HOWEVER...NOT EXPECTING A WIDESPREAD
BLOWING SNOW EVENT AS THE OFFICE BLOWING SNOW MODEL IS GIVING LOW
PROBABILITIES. THE STRONG SHORTWAVE DIVES INTO THE NORTHERN PLAINS
BY MONDAY. THE COLDEST AIR AND BEST FORCING FOR PRECIP WILL
REMAIN ACROSS THE DAKOTAS.
.LONG TERM...(TUESDAY THROUGH FRIDAY)
ISSUED AT 300 AM MST SAT JAN 9 2016
GOING TO STAY COLD IN THE LONG TERM AS UPPER RIDGE STAYS WEST OF
THE CWA AND WE STAY IN NORTHWEST FLOW. 700MB TEMPERATURES OF -8 TO
-10C OVER SOUTHEAST WYOMING SHOULD YIELD HIGHS IN THE 20S TO
POSSIBLY LOW 30S WITH LOWS IN THE SINGLE DIGITS AND LOW TEENS.
GFS HINTING AT INCREASING WINDS THAT COULD CHANGE TEMPERATURE
FORECAST. BY TUESDAY...700MB WINDS ON THE GFS INCREASE TO 40KTS
ACROSS SOUTHEAST WYOMING. 850MB WINDS OF 30 TO 35KTS OVER THE
PANHANDLE. WILL WAIT FOR ANOTHER RUN OR TWO BEFORE INCREASING
TEMPERATURES AND WINDS.
GUIDANCE DIFFERS ON SYSTEM FOR THE END OF THE WEEK. GFS MUCH
FASTER ON BRINGING IN THE NEXT PACIFIC SHORTWAVE THURSDAY WHILE
ECMWF SLOWER AND FURTHER NORTH WITH THE SYSTEM.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 501 AM MST SAT JAN 9 2016
LATEST HRRR GUIDANCE SHOWING IFR STRATUS MOVING INTO THE PANHANDLE
FROM THE NORTHEAST DURING THE MORNING HOURS. 11-3.9U SATELLITE
IMAGERY DOES SHOW A DECK MOVING SOUTHWEST...SO DO BELIEVE THIS
WILL HAPPEN. COULD PERSIST THROUGH THE AFTERNOON AS SUGGESTED BY
HRRR. DO THINK THOUGH THAT BY 18Z...CONDITIONS SHOULD IMPROVE.
WILL CONTINUE TO MONITOR.
&&
.FIRE WEATHER...
ISSUED AT 103 AM MST SAT JAN 9 2016
NO FIRE WEATHER CONCERNS. MINIMUM AFTERNOON HUMIDITY VALUES WILL
BE ABOVE 40 PERCENT. WIDESPREAD SNOW COVER WILL EXIST WITH THE
COLD TEMPERATURES.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
SHORT TERM...ZF
LONG TERM...GCC
AVIATION...GCC
FIRE WEATHER...ZF
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
341 AM MST SAT JAN 9 2016
.SHORT TERM...(TODAY THROUGH MONDAY NIGHT)
ISSUED AT 300 AM MST SAT JAN 9 2016
STILL GETTING VERY LIGHT SNOW OR FLURRIES IN AREAS ALONG
INTERSTATE 80...HOWEVER VISIBILITY IS MOSTLY ABOVE 3SM AND
ACCUMULATIONS ARE MINIMAL. THESE SNOW SHOWERS SHOULD GRADUALLY
DIMINISH THROUGH THE MORNING AS THE WEAK LIFT/SATURATION IN THE
700-500MB LAYER DEPARTS THE AREA. TEMPS WILL BE COLD TODAY WITH
MOST LOCATIONS STRUGGLING TO GET OUT OF THE LOW 20S (AROUND 15
DEGREES BELOW NORMAL). KEPT CHANCE POPS GOING FOR THE SIERRA
MADRE/SNOWY RANGES THROUGH THE EARLY EVENING HOWEVER ACCUMULATIONS
WILL BE LIGHT. NORTHWESTERLY FLOW ALOFT WILL REMAIN IN PLACE
THROUGH MONDAY WITH A CONTINUATION OF THE BELOW NORMAL
TEMPS...ALTHOUGH SOME PLACES WILL WARM TO AROUND FREEZING BY
MONDAY.
WILL SEE BREEZY-TO-WINDY CONDITIONS DEVELOP ACROSS SOUTHEAST WY
BY SUNDAY NIGHT INTO MONDAY AS PRESSURE FALLS OCCUR OVER
NEBRASKA/SOUTH DAKOTA AHEAD OF A SOUTHWARD-MOVING SHORTWAVE. THE
850MB CAG-CPR GRADIENT WILL INCREASE TO 45-50 METERS BY LATE
SUNDAY NIGHT SO WILL DEFINITELY SEE AN INCREASE IN WEST WINDS
ESPECIALLY IN THE WIND PRONE AREAS. WITH THE RECENT
SNOWFALL...COULD SEE SOME PATCHY BLOWING SNOW IN ARLINGTON AND
THE SOUTHERN LARAMIE RANGE. HOWEVER...NOT EXPECTING A WIDESPREAD
BLOWING SNOW EVENT AS THE OFFICE BLOWING SNOW MODEL IS GIVING LOW
PROBABILITIES. THE STRONG SHORTWAVE DIVES INTO THE NORTHERN PLAINS
BY MONDAY. THE COLDEST AIR AND BEST FORCING FOR PRECIP WILL
REMAIN ACROSS THE DAKOTAS.
.LONG TERM...(TUESDAY THROUGH FRIDAY)
ISSUED AT 300 AM MST SAT JAN 9 2016
GOING TO STAY COLD IN THE LONG TERM AS UPPER RIDGE STAYS WEST OF
THE CWA AND WE STAY IN NORTHWEST FLOW. 700MB TEMPERATURES OF -8 TO
-10C OVER SOUTHEAST WYOMING SHOULD YIELD HIGHS IN THE 20S TO
POSSIBLY LOW 30S WITH LOWS IN THE SINGLE DIGITS AND LOW TEENS.
GFS HINTING AT INCREASING WINDS THAT COULD CHANGE TEMPERATURE
FORECAST. BY TUESDAY...700MB WINDS ON THE GFS INCREASE TO 40KTS
ACROSS SOUTHEAST WYOMING. 850MB WINDS OF 30 TO 35KTS OVER THE
PANHANDLE. WILL WAIT FOR ANOTHER RUN OR TWO BEFORE INCREASING
TEMPERATURES AND WINDS.
GUIDANCE DIFFERS ON SYSTEM FOR THE END OF THE WEEK. GFS MUCH
FASTER ON BRINGING IN THE NEXT PACIFIC SHORTWAVE THURSDAY WHILE
ECMWF SLOWER AND FURTHER NORTH WITH THE SYSTEM.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 103 AM MST SAT JAN 9 2016
MAINLY MVFR CONDITIONS ACROSS THE NEBRASKA PANHANDLE AND SOUTHEAST
WYOMING WITH LIGHT SNOW. LATEST HRRR SHOWING SOME SIGNS OF
IFR/LIFR CONDITIONS IN THE PANHANDLE. SO FAR IT HAS NOT HAPPENED.
WILL CONTINUE TO MONITOR.
&&
.FIRE WEATHER...
ISSUED AT 103 AM MST SAT JAN 9 2016
NO FIRE WEATHER CONCERNS. MINIMUM AFTERNOON HUMIDITY VALUES WILL
BE ABOVE 40 PERCENT. WIDESPREAD SNOW COVER WILL EXIST WITH THE
COLD TEMPERATURES.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
SHORT TERM...ZF
LONG TERM...GCC
AVIATION...GCC
FIRE WEATHER...ZF
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
357 AM CST MON JAN 11 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 357 AM CST MON JAN 11 2016
A STRIPE OF CLOUDS HAS RESULTED IN MILDER TEMPERATURES FROM WEST
CENTRAL MN TO PORTIONS OF SOUTH CENTRAL MN EARLY THIS
MORNING...BUT CLEAR SKIES SURROUNDING THIS PATCH OF CLOUDS HAS
ALLOWED TEMPERATURES TO PLUMMET INTO THE TEENS AND IN SOME CASES
20S BELOW ZERO. THERE HAVE BEEN SPORADIC REPORTS OF FLURRIES WITH
THE DGZ EXTENDING FROM THE CLOUDS TO THE SURFACE AS WELL.
CLOUDS WILL INCREASE AND LOWER THIS MORNING AHEAD OF THE NEXT
WAVE/ARCTIC INTRUSION SET TO ARRIVE LATER TODAY. A 3 TO 5 HOUR
PERIOD OF LIGHT SNOW WILL ACCOMPANY THE WAVE. THE DEEPEST MOISTURE
AND STRONGEST FORCING /WHAT LITTLE THERE IS/ WILL BE COLLOCATED
ALONG AND NORTH OF I-94. THIS IS WHERE SOME ACCUMULATING SNOW IS
POSSIBLE. SNOW RATIOS WILL BE HIGH...BUT HOW HIGH WILL DEPEND ON
HOW LONG THE ISOTHERMAL PROFILE REMAINS IN THE DGZ BEFORE COOLING.
20 TO 25:1 RATIOS ARE POSSIBLE IF THE EVENT TAKES PLACE IN THE
FAVORABLE PROFILE WINDOW. MODELS SUGGEST THIS IS A GOOD
POSSIBILITY SO CONTINUED WITH A HALF TO ONE INCH ACCUMULATIONS
OVER MUCH OF THE AREA...HEAVIEST AMOUNTS OVER CENTRAL MN AND WRN
WI. UNFORTUNATELY FOR MANY...THE SNOW WILL FALL DURING EVENING
RUSH HOUR. THE VERY COLD START THIS MORNING WITH CLOUDS ARRIVING
AS THE SUN RISES SHOULD PUT A LIMIT ON HOW MUCH WE WARM TODAY.
THINK LOW TO MID SINGLE DIGITS IS ALL THE BEST WE CAN DO.
THE NEXT ROUND OF COLD AIR ARRIVES TONIGHT ON 10-20 MPH WINDS.
EXPECTING WIND CHILLS TO DROP INTO THE -20S AGAIN. A WIND CHILL
ADVISORY HAS BEEN POSTED. THE WIND MAY ALSO RESULT IN SOME PATCHY
BLOWING SNOW...PARTICULARLY ACROSS SRN MN WHERE SOME GUSTS TO 30
MPH ARE POSSIBLE.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 357 AM CST MON JAN 11 2016
THE LONG TERM CONCERNS REMAIN MODIFICATION OF ARCTIC AIR INTRUSION
INTO MIDWEEK WITH A REINFORCING COLD TROUGH MOVING IN FROM LATE
FRIDAY INTO NEXT WEEKEND.
MODELS IN GOOD AGREEMENT ON THE TEMPERATURE MODIFICATION DEVELOPING
WEDNESDAY AND CONTINUING THROUGH THURSDAY NIGHT. WE SHOULD SEE
TEMPERATURES WARMING BRIEFLY ABOVE NORMAL AGAIN BY THURSDAY. WITH
THIS WARMER AIR...WE WILL SEE A LEAST A SMALL CHANCE OF SOME LIGHT
SNOW/FLURRIES AS THE WARM AIR ARRIVES. SOME FAIR AMOUNT OF WAA
DEVELOPING AS BAROCLINIC ZONE STRENGTHENS WEDNESDAY INTO THURSDAY.
DECENT 300 MB 120 KT PLUS JET NOSES SOUTHEAST ALONG THIS BAROCLINIC
ZONE AND MOST MODELS DROP SOME LIGHT QPF WITH IT. WILL MENTION SO
SLIGHT CHANCES POPS FOR LIGHT SNOW/FLURRY ACTION OVER THE AREA
WEDNESDAY. QPF AMOUNTS OF A FEW HUNDREDTHS IS ABOUT RIGHT FOR THE
EVENT BUT SLR`S WILL LIKELY REMAIN HIGH GENERALLY 15 TO 20:1. SHOULD
REMAIN LESS THAN AN INCH MOST AREAS ACROSS THE NORTH AND EAST
PORTION OF THE CWA.
WINDS WILL LIGHTEN INTO TUESDAY NIGHT IN THE WAKE OF THE TROUGH
PASSAGE. HOWEVER...WE COULD SEE ENOUGH WIND TO HAVE SOME WIND CHILL
CONCERNS LATE TUESDAY NIGHT AND WEDNESDAY MORNING MAINLY IN WEST
CENTRAL WISCONSIN.
STILL SEE SOME MODEL DIVERGENCE DEVELOPING FRIDAY AND INTO THE
WEEKEND. THE ECMWF IS ADAMANT IN TAKING THE SOUTHERN STREAM STORM
SOUTH OF THE AREA AS THE NORTHERN STREAM BUCKLES AGAIN CARVING OUT
ANOTHER EASTERN CONUS TROUGH. THIS SHOULD DUMP ANOTHER SHOT OF
ARCTIC AIR OVER THE NORTHERN PLAINS AND GREAT LAKES THROUGH THE
WEEKEND. LONG RANGE TEMPERATURES SEEM TOO WARM. STARTED TO COOL THEN
A COUPLE OF DEGREES FOR THE WEEKEND FOR NOW. THE EUROPEAN GUIDANCE
HAS TEMPERATURES REMAINING BELOW ZERO AGAIN NEXT SATURDAY...AND
STRUGGLING ABOVE ZERO SUNDAY...OR SOME 20 DEGREES BELOW NORMAL.
THE GFS LIFTED THE STORM FARTHER NORTH ON THE 00Z RUN...WHICH
WOULD BE FAR ENOUGH NORTH OF A STORM TRACK TO BRING SOME
ACCUMULATING SNOW TO AT LEAST THE EASTERN HALF OF THE CWA. THERE
WERE SEVERAL GFS ENSEMBLE MEMBERS ALSO CONFIRMING A MORE NORTHERN
TRACK...WITH THE MEAN CLOSE TO THE DETERMINISTIC RUN. WE WONT GO
ALL IN ON THE ECMWF RIGHT NOW BECAUSE OF THIS. WE WILL MONITOR
NEXT MODEL RUN AND SEE IF THERE IS MORE CONFIRMATION OF EITHER
TREND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 959 PM CST SUN JAN 10 2016
MAIN ISSUE FOR THE FIRST 12 HOURS OR SO IS THE PATCHWORK OF MVFR
CEILINGS IN WEST CENTRAL...CENTRAL AND SOUTHWEST MN. THIS HAS
GENERALLY BEEN SLOWLY EXPANDING AND STREAMING TO THE SOUTHEAST.
MOST RECENT HI-RES MODELS SUGGEST THIS WILL PERSIST WELL INTO
MONDAY MORNING. WITH THE RIDGE SLIDING EAST...WARM ADVECTION INTO
MN SHOULD ALLOW THIS TO CONTINUE EXPANDING SLOWLY ACROSS
WESTERN/SOUTHERN MN. MOST LIKELY AREA TO AVOID THE STRATUS WILL
BE EAST CENTRAL MN INTO WISC...BUT EVEN HERE THERE MAY BE SOME
ISOLATED POCKETS OF ICE CRYSTALS AND SHALLOW IFR CEILINGS IN THE
ARCTIC AIR.
MONDAY AFTERNOON/EVENING...A WEAK CLIPPER LOW PRESSURE SYSTEM
WILL BRING AN INCREASING CHANCE OF LIGHT SNOW AND MVFR CONDITIONS
FOR 4-6 HOURS IN ANY GIVEN SPOT. THIS SNOW SHOULD BEGIN MID
AFTERNOON IN WEST CENTRAL MN AND QUICKLY SLIDE TO THE SOUTHEAST.
SOME VISIBILITIES MAY DROP TO 2SM...BUT WILL NOT BE SHOCKED IF
THERE ARE SOME AREAS OF 1SM IN THE SNOW FROM CENTRAL MN INTO WISC.
SHOULD ALSO MENTION THAT SW MN MAY ONLY GET A GLANCING BLOW.
KMSP...MVFR CEILINGS AROUND 1800 FT AGL EXPANDING/DEVELOPING TO
THE SOUTHEAST...AND MAY REACH KMSP SHORTLY AFTER 06Z. SHORT TERM
MODELS HAVE NOT BEEN HANDLING THIS WELL...BUT THE LATEST RAP DOES
GIVE SOME HINT THAT THE MVFR MAY PERSIST MUCH OF MONDAY MORNING.
GIVEN THE WARM ADVECTION PATTERN AND THE COLD ARCTIC AIR...SUSPECT
MVFR WILL INDEED HANG AROUND MUCH OF MONDAY MORNING. THEN THE
CLIPPER ARRIVES WITH LIGHT SNOW LATE MONDAY AFTERNOON FOLLOWED BY
INCREASING NORTHWEST WINDS LATER MONDAY NIGHT. HAVE INDICATED 2SM
VISIBILITY IN THE LIGHT SNOW. LOWER VISIBILITIES IN SNOW SHOULD BE
A LITTLE NORTH OF KMSP...BUT THIS WILL BE CLOSE.
/OUTLOOK FOR KMSP/
TUE...VFR. WINDS NW 10-15G25 KTS.
WED...VFR. WINDS SW 5-10 KTS.
THU...VFR. WINDS SW 5-10 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
WI...WIND CHILL ADVISORY FROM 3 AM TO NOON CST TUESDAY FOR WIZ014>016-
023>028.
MN...WIND CHILL ADVISORY FROM 3 AM TO NOON CST TUESDAY FOR MNZ053-
060>063-067>070-073>078-082>085-091>093.
WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO NOON CST TUESDAY
FOR MNZ041>045-047>052-054>059-064>066.
&&
$$
SHORT TERM...BORGHOFF
LONG TERM...DWE
AVIATION...TDK
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
343 AM EST MON JAN 11 2016
.SYNOPSIS...
A WESTERLY FLOW OF COLD AND MOIST AIR WILL BRING SCATTERED SNOW
SHOWERS AND FLURRIES TO A LARGE PART OF CENTRAL NEW YORK AND
NORTHEAST PENNSYLVANIA TODAY. A LOW PRESSURE SYSTEM WILL TRACK
ACROSS THE GREAT LAKES TONIGHT TO OFF THE NEW ENGLAND COAST BY
TUESDAY NIGHT. THIS SYSTEM WILL BRING A WIDESPREAD INCH OR TWO OF
SNOW TO THE REGION TUESDAY. AFTER THIS SYSTEM PASSES BY, HEAVY
LAKE EFFECT SNOW WILL BE POSSIBLE ALONG THE THRUWAY CORRIDOR FROM
SYRACUSE TO UTICA AND ROME TUESDAY NIGHT AND WEDNESDAY. ELSEWHERE
EXPECT SCATTERED SNOW SHOWERS AND FLURRIES WITH ONLY LIGHT
ACCUMULATIONS THROUGH WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
RADAR IMAGERY SHOWS MAIN LAKE EFFECT SNOW BAND NORTH OF ONEIDA
COUNTY. THE KTYX VAD WIND PROFILE IS SHOWING A 260 DEGREE FLOW
FROM 3 TO 8 THOUSAND FEET ABOVE SEA LEVEL AND WAS DIRECTING THE
LAKE EFFECT SNOWS TO OUR NORTH. THE 00Z RGEM, 00Z NAM12,
WRF_ARW,AND HRRR WERE ALL KEEPING THIS BAND TO OUR NORTH THROUGH
THE DAY. THE ONLY HI RES MODEL THAT WAS BRINGING THE BAND INTO
NORTHERN ONEIDA COUNTY TODAY WAS THE WRF_NMM. THE MODELS HAVE
TRENDED NORTH WITH THE BAND FROM YESTEDAY AND CURRENT RADAR
INDICATES THAT THIS WILL BE THE CASE SO WILL KEEP SIGNIFICANT
SNOWS OUT OF OUR FORECAST AREA TODAY. LAKE EFFECT SNOW WARNINGS
ARE OUT TO OUR NORTH AND LOOK GREAT. THE REST OF THE FORECAST AREA
WAS SEEING SCATTERED SNOW SHOWERS AND FLURRIES ON A WEST TO
SOUTHWEST FLOW. NAM AND GFS SOUNDINGS ARE SHOWING VERY STEEP LOW-
LEVEL LAPSE RATES THRU THE MORNING WHICH WAS LEADING TO SOME
SMALL CAPE UNDER THE INVERSION WHICH WAS AT ABOUT 800 MB OR 5000
FEET. THIS WAS ENOUGH TO ORGANIZE SOME SNOW SHOWERS AND FLURRIES.
MUCH OF THIS SMALL CAPE WAS IN THE MAX GROWTH REGIME FOR ICE
CRYSTALS. AS THE DAY PROGRESSES THE BOUNDARY LAYER WILL CONTINUE
TO BE DRYING AND I EXPECT THE ACVTY TO MOVE BACK CLOSER TO THE
LAKES. SO I HAVE SCATTERED SNOW SHOWERS AND FLURRIES DIMINISHING
SOME TO THE WEST.
AS FOR WINDS SYR JUST GUSTED TO 40 KNOTS AND RME WAS STILL HITTING 38
KNOTS WHICH IS CLOSE TO ADVY CRITERIA. WILL HOLD ONTO WIND ADVY
UNTIL WINDS MARKEDLY DROP OFF.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
FOR TONIGHT AND TUESDAY...ALL MODELS SHOW A CLIPPER-TYPE SYSTEM
TRACK FROM THE GREAT LAKES REGION TONIGHT TO NORTH OF LAKE
ONTARIO BY TUESDAY EVENING AND THEN TO OFF THE NEW ENGLAND COAST
BY WEDNESDAY MORNING. AS THIS SYSTEM APPROACHES NEW YORK AND
PENNSYVANIA THE LOW-LEVEL WINDS WILL BACK TO THE SOUTHWEST AND
SEND ANY RESIDUAL LAKE EFFECT SNOW SHOWERS TO THE NORTH OR CUT
THEM OFF FROM THEIR SOURCE REGION. SO I DRY OUT TONIGHT IN OUR
FORECAST. ALL SYNOPTIC SCALE MODELS SHOW A REGION OF WARM AIR
ADVECTION (OR ISENTROPIC LIFT IF YOU PREFER THAT COORDINATE
SYSTEM) ACROSS NEW YORK AND PENNSYLVANIA TUESDAY MORNING. HOWEVER
THIS SYSTEM WILL BE MOISTURE STARVED AND SOUTHWEST WINDS TEND TO
DOWNSLOPE ACROSS A WIDE AREA OF CENTRAL NY AND NORTHEAST PA. THE
EXCEPTIONS ARE THE CATSKILLS AND SOUTHERN TUG HILL PLATEAU AND
ALLEGHENIES OF WESTERN NY. THEN AS THE CLIPPER TRACKS TO OUR
NORTHEAST TUESDAY AFTERNOON THERE IS SOME LAKE ENHANCED COLD FRONTAL
SNOW SHOWERS THAT WILL ADD A BIT MORE TO THE TOTAL ACCUMULATIONS.
FOR NOW WE SEE MOST AREAS GETTING AROUND 1 INCH WITH LOCALLY 2-3
INCHES IN THE CATSKILLS TO UPPER MOHAWK AND SOUTHERN TUG HILL
PLATEAU AND WESTERN STEUBEN COUNTY.
AFTER THIS SYSTEM PASSES TUESDAY EVENING, THE INVERSION CLIMBS TO
ALMOST 700 MB AND THE MEAN WIND IN THIS LAYER IS FROM 280-290
DEGREES. BOTH THE GFS AND NAM MODEL SOUNDINGS BETWEEN ABOUT 6Z-9Z
AND 18Z-21Z WEDNESDAY INDICATE UPWARD MOTION IN THE MAX ICE
CRYSTAL GROWTH REGIME SUGGESTING SIGNIFICANT SNOW GROWTH
POTENTIAL. THE 850 MB TEMPERATURES WERE AROUND -18C WHICH GIVES AT
LEAST A 23C DIFFERENTIAL WHICH IS EXTREME LAKE-INDUCED
INSTABILITY. THE ONLY UNCERTAINITY IS THE EXACT WIND DIRECTION
WHICH IS STILL SOMEWHAT UNCERTAIN. IT LOOKS LIKE AT LEAST 8-12
INCHES OF SNOW TUESDAY NGT AND WEDNESDAY AND POSSIBLY MORE
SOMEWHERE IN ONONDAGA, MADISON OR ONEIDA COUNTIES. THIS COULD BE
A BIG EVENT FOR THE THRUWAY CORRIDOR, THE FIRST OF THIS LATE
EVOLVING WINTER SEASON. ISSUED LAKE EFFECT SNOW WATCHES FOR
TUESDAY NIGHT AND WEDNESDAY TO COVER FOR ONONDAGA, ONEIDA AND
MADISON COUNTIES.
ALL LAKE EFFECT ACTIVITY WINDS DOWN WED NGT AS FLOW BACKS MORE
SOUTHWESTERLY.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
AS THE CLIPPER LIFTS TO THE NORTH TUE NIGHT AND EARLY WED...WEAK
RIDGING WILL OCCUR ON THE BACK SIDE OF THE SYSTEM AND KEEP THE
WINDS IN A FAVORABLE NW DIRECTION FOR ANOTHER ROUND OF LAKE
EFFECT SNOW INTO CENTRAL NY. THE WIND FIELD WILL LIKELY WAVER BACK
AND FORTH BETWEEN NW AND WEST THROUGH THURSDAY AND FRIDAY...BUT
WITH ENOUGH OF A CONTINUOUS INFLUX OF COLD AIR TO KEEP THE LAKE
BANDS GOING. AT THIS TIME IT APPEARS THE WED THROUGH THURSDAY
NIGHT TIME PERIOD APPEARS TO BE THE MOST FAVORABLE FOR SIGNIFICANT
LAKE EFFECT SNOW ACCUMULATIONS ACROSS THE NRN COUNTIES. WILL NEED
TO KEEP AN EYE ON THIS EVENT AS IT DEVELOPS THROUGH THE WEEK AND
MODEL GUIDANCE GETS A BETTER HANDLE ON THE WIND TRAJECTORIES.
A WEAK RIDGE OF HIGH PRESSURE EVENTUALLY BUILDS IN FROM THE NORTH
ON FRIDAY AND ALLOWS THE LES TO END. THE PATTERN IS EXPECTED TO
REMAIN ACTIVE HOWEVER INTO THE WEEKEND AS ANOTHER STORM SYSTEM IS
FORECAST TO DEVELOP OVER THE OHIO VALLEY AND LIFT INTO THE NE
THROUGH THE WEEKEND. IT IS TOO EARLY TO DETERMINE THE EXACT NATURE
OF THIS SYSTEM...BUT ALL SIGNS POINT TO A WINTRY STORM SYSTEM.
&&
.AVIATION /08Z MONDAY THROUGH FRIDAY/...
ARCTIC AIR IS OVERSPREADING THE REGION...TOUCHING OFF LOCALIZED LAKE
EFFECT SNOW SHOWERS AND ASSOCIATED BRIEF RESTRICTIONS. IN GENERAL
THOUGH PREDOMINANTLY VFR AND WITH GUSTY WEST WINDS THROUGH THE COMING
DAY. NARROW BANDS OF INTERMITTENT MVFR-IFR VIS SNOW SHOWERS WILL
COME OVER FROM LAKE ERIE FIRST FOR KELM DURING PREDAWN
HOURS...LIFTING- EXTENDING TO KBGM TOWARDS DAWN...THEN UP TO KITH
MID-TO-LATE MORNING. LAKE ONTARIO SNOW BANDS WILL BE A NON-
ISSUE...STAYING NORTH OF KSYR-KRME. WESTERLY WINDS 15-2O KTS WITH
GUST 25-3O KTS THIS MORNING THROUGH MID AFTERNOON...PERHAPS A
TOUCH HIGHER FOR KSYR...THEN DIMINISHING WHILE BACKING
SOUTHWESTERLY INTO THIS EVENING.
.OUTLOOK...
TUE/TUE NGT...CLIPPER SYSTEM WITH SHOT OF WIDESPREAD -SN AND
RESTRICTIONS TUE...THEN LAKE SHSN MAINLY NY TERMINALS TUE NGT.
WED/THU...LAKE EFFECT SHSN AND ASSOCIATED INTERMITTENT
RESTRICTIONS MAINLY NY TERMINALS.
FRI...MAINLY VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...LAKE EFFECT SNOW WATCH FROM TUESDAY EVENING THROUGH WEDNESDAY
EVENING FOR NYZ009-018-036-037.
WIND ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR NYZ009-
015>018-022-036-037.
&&
$$
SYNOPSIS...DJN
NEAR TERM...DJN
SHORT TERM...DJN
LONG TERM...BJT
AVIATION...MDP
AREA FORECAST DISCUSSION
NWS BISMARCK ND
324 AM CST MON JAN 11 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 315 AM CST MON JAN 11 2016
HIGHLIGHTS IN THE SHORT TERM INCLUDE PATCHY BLOWING SNOW ALONG
WITH ISOLATED TO SCATTERED SNOW SHOWERS REDUCING VISIBILITIES
MONDAY AFTERNOON/EVENING. THE HIGHEST CONCERN IS THE FAR SOUTHWEST
WHERE 1 TO 2 INCHES OF SNOW THIS AFTERNOON COMBINED WITH GUSTY
WINDS PUTS THIS AREA AT GREATEST RISK FOR A POSSIBLE WINTER
WEATHER ADVISORY FOR BLOWING SNOW WITH VISIBILITIES AROUND ONE
HALF MILE. FOR NOW WE HAVE DECIDED TO MONITOR THE HRRR AND RAP13
BUFKIT SOUNDINGS TO SEE IF CURRENT TRENDS OF STRONGER WINDS
CONTINUE OVER THE NEXT SEVERAL HOURS. THAT ALLOWS SUFFICIENT TIME
IN THE NEXT ONE TO TWO UPDATE CYCLES TO ISSUE SOMETHING IF THE
SITUATION WARRANTS. OTHERWISE...WIND CHILL TEMPERATURES 25 TO 30
BELOW ZERO EXPECTED LATE MONDAY NIGHT NORTH CENTRAL AND INTO THE
NORTHERN JAMES RIVER VALLEY THROUGH TUESDAY MORNING. AFTER
COLLABORATING WITH NEIGHBORING OFFICES WILL AGAIN LET THE DAYSHIFT
HONE IN ON THE COUNTIES AFTER ANOTHER MODEL CYCLE COMES IN THIS
MORNING AND AFTERNOON.
THE LATEST WATER VAPOR IMAGERY SHOWS THIS NEXT SHORTWAVE THROUGH
NOW STREAMING THROUGH NORTHWEST SASKATCHEWAN AND DIVING SOUTHEAST
WITH TIME. ACCOMPANYING THE SHORTWAVE IS A 300MB 140KT JET STREAK.
WITH THE JET AND SHORTWAVE MAINTAINING A SOUTHEAST MOVEMENT THROUGH
00Z TUESDAY...THE FAVORED LEFT EXIT REGION OF THE JET FOR LARGE
SCALE ASCENT REMAINS JUST OFF TO OUR EAST. HENCE PRECIPITATION
AMOUNTS WILL REMAIN LIGHT AND THIS LIMITS SIGNIFICANT REDUCTIONS
IN VISIBILITIES. THE EXCEPTION WILL BE ACROSS THE HIGHER TERRAIN
IN THE FAR SOUTHWEST CLOSEST TO THE BAROCLINIC ZONE AND STRONGER
OMEGA/VERTICAL MOTION...FAVORING HIGHER AMOUNTS OF SNOWFALL.
ASSOCIATED WITH THE SHORTWAVE MENTIONED ABOVE IS AN ARCTIC FRONT
IN SOUTHERN ALBERTA/SASKATCHEWAN/MANITOBA...WHICH WILL SWEEP DOWN
ACROSS WESTERN AND CENTRAL NORTH DAKOTA TODAY. GUSTY NORTHWEST
WINDS BETWEEN 20 AND 35 MPH WILL DEVELOP IN ITS WAKE THIS AFTERNOON
AND INTO THE EARLY EVENING. THE STRONGEST WINDS FORECAST ACROSS
THE NORTH CENTRAL AND JAMES RIVER VALLEY WHICH FOLLOWS THE LOCATION
AND TRAJECTORY OF THE 6HR PRESSURE RISES AND UPPER JET MENTIONED
ABOVE. THE BAGGALEY BLOWING SNOW INDICATING THAT ONLY A VERY SMALL
AREA ACROSS THE NORTH CENTRAL WOULD BE IN LINE FOR A VERY LOW END
WINTER WEATHER ADVISORY FOR BLOWING SNOW...IF ONLY BLOWING SNOW
OCCURRED. ADDING A MENTION OF SNOWSHOWERS INTO THE FORMULA WITH A
WORST CASE SCENARIO OF AN INCH OF SNOW...A MORE WIDESPREAD LOW END
ADVISORY SHOWS UP. HOWEVER EXPECTATIONS ARE THAT SNOWFALL AMOUNTS
WILL REMAIN WELL UNDER ONE INCH...WITH THE EXCEPTION OF THE FAR
SOUTHWEST AS MENTIONED ABOVE. THUS WE HAVE DECIDED TO CONTINUE
WITH THE SPECIAL WEATHER STATEMENT ADVERTISING DRIFTING SNOW AND
PATCHY BLOWING SNOW REDUCING VISIBILITIES MAINLY IN OPEN COUNTRY.
MONDAY EVENING THE SURFACE WINDS WILL BEGIN DIMINISHING AS BOUNDARY
LAYER WINDS WEAKEN TO AROUND 20KT BY 06Z TUESDAY. SURFACE HIGH
PRESSURE MOVES FROM NEAR PLENTYWOOD MONTANA 06Z TUESDAY SOUTHEAST
INTO SOUTH CENTRAL SOUTH DAKOTA 12Z TUESDAY.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 315 AM CST MON JAN 11 2016
DANGEROUS WIND CHILLS TUESDAY MORNING...A POSSIBLE WARM UP INTO
THURSDAY...FOLLOWED BY ANOTHER POTENTIAL ARCTIC AIRMASS FOR FRIDAY
INTO THE WEEKEND HIGHLIGHT THE EXTENDED FORECAST.
DANGEROUS WIND CHILLS TO 30 BELOW ARE POSSIBLE ACROSS PORTIONS OF
CENTRAL NORTH DAKOTA TUESDAY MORNING IN ASSOCIATION WITH THE
ARCTIC AIRMASS ARRIVING MONDAY. THE WESTERN FRINGE OF THIS ARCTIC
AIRMASS IS FORECAST BY THE 00 UTC DETERMINISTIC AND ENSEMBLE
SUITES TO PROPAGATE EAST WEDNESDAY AND THURSDAY. THE RESULT IS A
POTENTIAL WARM UP WITH HIGHS WEDNESDAY AND THURSDAY IN THE UPPER
20S TO LOWER 30S ALONG AND WEST OF THE MISSOURI RIVER.
HOWEVER...AS HAS BEEN THE TREND OVER THE PAST COUPLE
DAYS...ANOTHER ARCTIC AIRMASS IS FORECAST TO POSSIBLY OVERTAKE THE
NORTHERN PLAINS FRIDAY INTO THE WEEKEND.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY) ISSUED AT 315 AM
CST MON JAN 11 2016
MVFR CIGS AT KISN/KDIK/KMOT WILL SPREAD SOUTHEAST TODAY WITH ALL
TERMINALS MVFR THROUGH AT LEAST 02Z TUESDAY. MVFR CIGS EXPECTED
AT KBIS/KJMS AFTER 17Z MONDAY. GUSTY NORTHWEST WINDS TO 30KT
MONDAY AFTERNOON IN CONJUNCTION WITH ISOLATED SNOW SHOWERS
WILL LEAD TO -SN/BLSN AND VSBYS IN THE MVFR RANGE BETWEEN 18Z
MONDAY AND 02Z TUESDAY. WINDS WILL DIMINISH AFTER 00Z TUESDAY
WITH CIGS SLOWLY IMPROVING TO LOW VFR THROUGH 12Z TUESDAY.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...KS
LONG TERM...AYD
AVIATION...KS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1129 PM CST SUN JAN 10 2016
.UPDATE...
ISSUED AT 1129 PM CST SUN JAN 10 2016
LATEST WATER VAPOR IMAGERY LOOP INDICATES UPPER SHORTWAVE TROUGH
NEAR WATFORD CITY...WITH VERTICAL MOTION MAXIMIZED PER 3HR
SURFACE PRESSURE MAX FROM BISMARCK NORTH TO MINOT. WITHIN THIS
AREA OF VERTICAL MOTION...LOCAL RADAR SHOWING A SMALL BUT FAST
MOVING AREA OF WEAK REFLECTIVITYS FROM COLEHARBOR IN MCLEAN
COUNTY TO CROWN BUTTE LAKE IN MORTON COUNTY...MOVING SOUTHEAST
WITH TIME. THE LEADING EDGE OF THIS AREA IS JUST MAKING IT INTO
BISMARCK WITH LIGHT SNOW OCCURRING AT THE BISMARCK AIRPORT.
EXPECT THIS AREA OF LIGHT SNOW TO MOVE QUICKLY SOUTHEAST OVER THE
NEXT FEW HOURS AS THE SHORTWAVE MENTION ABOVE ADVANCES INTO
CENTRAL SOUTH DAKOTA BY 12Z MONDAY. HAVE UPDATED POPS FOR THIS
AREA OF LIGHT SNOW. RISING TEMPERATURES ON TRACK OVERNIGHT WITH
WARM AIR ADVECTION PEAKS FROM WEST TO EAST.
UPDATE ISSUED AT 931 PM CST SUN JAN 10 2016
HAVE SOME ISSUES WITH TEMPERATURES TONIGHT. WARM FRONT ACROSS
SOUTHWEST NORTH DAKOTA ALREADY KEEPING TEMPERATURES IN THE LOWER
20S THIS EVENING ALTHOUGH BAKER IS 26 NOW VS 20 AT 6 PM.
TEMPERATURES RISES HELPED WITH GUSTY WEST/NORTHWEST WINDS BEHIND
THE FRONT. HRRR MODEL PRODUCES JUST A SMALL AREA OF LIGHT PRECIP
ACROSS THE SOUTHWEST THIS EVENING WHICH SEEMS TO FIT WITH CURRENT
TRENDS. UPDATED POPS AND TRENDED THE TEMPS UP A BIT OVERNIGHT.
UPDATE ISSUED AT 554 PM CST SUN JAN 10 2016
SURFACE HIGH PRESSURE OVER EASTERN NORTH DAKOTA WILL MOVE EAST
TONIGHT AS A LEE SIDE TROUGH REMAINS IN MONTANA. A WEAK H500
SHORTWAVE WILL TRACK ACROSS THE WESTERN PORTION OF THE STATE
TONIGHT. ASSOCIATED LOW LEVEL WARM ADVECTION AND CLOUDS ACROSS THE
WEST AND CENTRAL WILL FAVOR NON DIURNAL TEMPERATURES TONIGHT WITH
OVERNIGHT LOWS LIKELY THIS EVENING OR SHORTLY AFTER MIDNIGHT...
ESPECIALLY ACROSS THE JAMES RIVER VALLEY...FOLLOWED BY RISING
TEMPERATURES LATER TONIGHT. THIS FEATURE WILL BE FOLLOWED BY A
BIT MORE VIGOROUS SHORTWAVE ON MONDAY AFTERNOON BRINGING GUSTY
WINDS AND A CHANCE FOR SNOW. SO FAR THE CURRENT FORECAST SEEMS TO
BE TRACKING OK. WILL MAINLY UPDATE CURRENT CONDITIONS.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 315 PM CST SUN JAN 10 2016
GUSTY WINDS...DRIFTING AND POSSIBLY SOME BLOWING SNOW ALONG WITH
A CHANCE OF LIGHT FALLING SNOW ON MONDAY IS OUR MAIN FOCUS.
A QUICK-MOVING SHORTWAVE TROUGH IN NORTHWEST FLOW WILL CROSS THE
AREA TONIGHT. GIVEN MODEST QG-FORCING FORCING IN MODEL SOLUTIONS
AND SOME INCREASE IN RADAR ECHOES UPSTREAM IN MT AS OF 21 UTC...A
SLIGHT CHANCE OF LIGHT SNOW IS PRUDENT IN THE FORECAST TONIGHT AT
LEAST FOR A TIME IN MOST AREAS. BEFORE CLOUD COVER INCREASES WITH
THE APPROACH OF THAT WAVE...TEMPERATURES IN CENTRAL ND MAY TUMBLE
QUICKLY WITH SUNSET GIVEN LIGHT WINDS AND POOR RECOVERY TODAY. WE
THUS UNDERCUT GUIDANCE LOWS OVER CENTRAL ND TONIGHT...ESPECIALLY
IN THE JAMES RIVER VALLEY...WHERE WE HAVE LOWS OF -10 TO -15. THE
TEMPERATURES SHOULD EVENTUALLY RISE OVERNIGHT AS CLOUDS INCREASE.
ON MONDAY...ANOTHER...STRONGER SHORTWAVE TROUGH WILL INDUCE A NEW
ARCTIC SURGE WITH A SURFACE COLD FRONT TRANSITING THE AREA QUICKLY
DURING THE MIDDAY HOURS. DEEP-LAYER FORCING IS WEAK...BUT FORECAST
SOUNDINGS SUGGEST A SATURATED LAYER /STRATUS DECK/ BASED IN THE
DENDRITIC GROWTH ZONE...WHICH MAY LEAD TO A HIGH POP/LOW QPF TYPE
OF SITUATION WITH A SEVERAL-HOUR PERIOD OF LIGHT SNOW POSSIBLE. WE
EXPECT ACCUMULATIONS LESS THAN AN INCH OVER ALL BUT FAR SOUTHWEST
ND...WHERE TOTAL SNOWFALL COULD BE AROUND AN INCH SINCE OMEGA WILL
BE SOMEWHAT STRONGER CLOSER TO A LOW- TO MID-LEVEL BAROCLINIC ZONE.
WINDS WILL BE THE GREATER CONCERN...BUT THE 00 AND 12 UTC MODELS
HAVE GRADUALLY RELAXED WIND SPEEDS ALOFT AND BOUNDARY LAYER WINDS
FROM THE 12 UTC GFS AND NAM ONLY RAN 25-30 KT. THERE WILL ALSO BE
MODEST SURFACE PRESSURE RISES OF 3-5 MB/3 HR FOLLOWING THE FRONT.
THUS...WE DO EXPECT GUSTS TO 35 MPH MOST AREAS MONDAY AFTERNOON.
THE BAGGALEY BLOWING SNOW MODEL SUGGESTS THE PROBABILITY OF 1/2SM
VISIBILITY FROM PURE BLOWING SNOW IS ON THE FRINGES OF THE VALUES
WE WOULD TYPICALLY EXPECT TO REQUIRE A WINTER WEATHER ADVISORY AS
A RESULT OF AN OLD SNOW PACK AND LACK OF STRONGER LOW-LEVEL COLD
AIR ADVECTION. HOWEVER...THAT GUIDANCE ALSO SUGGESTS REDUCTIONS IN
VISIBILITY FROM LIGHT FALLING SNOW IN THE GUSTY WINDS MAY BE MORE
DRAMATIC...ALBEIT SHORTER-LIVED. ALL CONSIDERED...WE FELT THAT
THIS EVENT IS BEST-HANDLED USING A SPECIAL WEATHER STATEMENT. WE
WILL RELY ON LATER RAPID-REFRESH GUIDANCE AND OBSERVATIONAL TRENDS
TO DETERMINE IF FALLING SNOW WILL LAST LONG ENOUGH IN ANY ONE AREA
TO PRODUCE A LONGER-LIVED BLOWING SNOW ISSUE THAT MIGHT REQUIRE US
TO ISSUE AN ADVISORY. THE PROBABILITY OF BLOWING SNOW IS GREATEST
IN CENTRAL ND REGARDLESS...WHERE THE SNOW PACK IS DEEPEST.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 315 PM CST SUN JAN 10 2016
AFTER ANOTHER BELOW ZERO NIGHT MONDAY NIGHT WITH DANGEROUS WIND
CHILLS...A WARMING TREND ENSUES...THEN A CHANCE OF LIGHT SNOW
THURSDAY INTO FRIDAY WITH A COOLING TREND.
MONDAY NIGHT THE ARCTIC HIGH CENTER MOVES SOUTHEAST FROM
ALBERTA/SASKATCHEWAN AT SUNSET MONDAY EVENING...TO THE CENTRAL
DAKOTAS BY DAYBREAK TUESDAY MORNING. OVERNIGHT LOWS SHOULD RANGE
FROM AROUND 10 BELOW IN THE TURTLE MOUNTAIN REGION TO AROUND 5 ABOVE
IN THE FAR SOUTHWEST. ALTHOUGH NORTHWEST WINDS SHOULD BE DIMINISHING
THROUGH THE NIGHTTIME HOURS...DANGEROUS WIND CHILLS ARE EXPECTED TO
DEVELOP LATE MONDAY NIGHT ALONG AND NORTH OF A LINE FROM FROM AROUND
CROSBY IN THE NORTHWEST TO JAMESTOWN. THE DANGEROUS WIND CHILLS ARE
FORECAST TO LINGER THROUGH THE MORNING HOURS ON TUESDAY.
A WESTERN RIDGE CURRENTLY OVER THE WEST COAST PUSHES EAST ACROSS THE
ROCKIES AND EXPANDS INTO THE WESTERN PLAINS TUESDAY/TUESDAY
NIGHT...BRINGING WARM ADVECTION TO WESTERN NORTH DAKOTA DURING THE
DAY TUESDAY. A NOTICEABLE TEMPERATURE CONTRAST ON TUESDAY WITH HIGHS
ONLY EXPECTED TO BE AROUND ZERO IN THE TURTLE MOUNTAIN AREA...BUT
REACH INTO THE LOWER 20S IN THE SOUTHWEST.
WARMER ON WEDNESDAY AS THE WARM RIDGE PUSHES FARTHER EAST. HIGHS
WEDNESDAY AND THURSDAY FROM THE TEENS IN THE TURTLE MOUNTAINS TO THE
LOWER 30S IN THE SOUTHWEST.
ALONG WITH THE WARM ADVECTION THURSDAY...THE MODELS ARE INDICATING A
SHORTWAVE BREAKING DOWN THE WARMING RIDGE...INDICATING A MORE ACTIVE
PATTERN WITH A CHANCE OF LIGHT SNOW THURSDAY INTO FRIDAY ALONG
WITH A COOLING TREND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1129 PM CST SUN JAN 10 2016
CIG TREND IN THIS TAF PERIOD WILL TRANSITION FROM VFR TO MVFR AT
ALL TERMINALS. KISN AND KDIK CIGS WILL DETERIORATE EARLY IN THIS
PERIOD...BETWEEN 06Z-09Z MONDAY. MVFR CIGS EXPECTED AT
KMOT/KBIS/KJMS AFTER 17Z MONDAY. GUSTY NORTHWEST WINDS TO 30KT-35KT
MONDAY AFTERNOON IN CONJUNCTION WITH VERY LIGHT SNOW WILL LEAD TO
-SN/BLSN AND VSBYS IN THE MVFR RANGE BETWEEN 18Z MONDAY AND 02Z
TUESDAY. WINDS WILL DIMINISH AFTER 00Z TUESDAY HOWEVER CIGS WILL
REMAIN IN MVFR STATUS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KS
SHORT TERM...CJS
LONG TERM...JV
AVIATION...KS
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
203 AM EST MON JAN 11 2016
.SYNOPSIS...
A DEEP UPPER LEVEL TROUGH WILL PIVOT THROUGH THE NORTHEAST CONUS
EARLY THIS WEEK...WITH AN ALBERTA CLIPPER TRACKING NORTH OF THE
COMMONWEALTH ON TUESDAY. THE UPPER TROUGH WILL LIFT OUT OF THE
REGION BY THE END OF THE WEEK.
&&
.NEAR TERM /UNTIL 8 AM THIS MORNING/...
BLUSTERY CONDS WILL CONTINUE FOR THE BALANCE OF THE NIGHT...AS
TIGHT GRADIENT GRADUALLY WEAKENS SOUTH OF INTENSE SFC LOW OVR
QUEBEC. BUFKIT SOUNDINGS SUGGEST THERE WILL BE FREQUENT GUSTS TO
ARND 30KTS THRU DAWN. PLUMMETING TEMPS...COMBINED WITH THE GUSTY
WINDS...WILL LIKELY CREATE WCHILLS NEAR ZERO ACROSS THE W MTNS BY
MON AM.
COLD WESTERLY FLOW IS PRODUCING GENERALLY LIGHT LAKE-ENHANCED
OROGRAPHIC SNOW SHOWERS ACROSS THE ALLEGHENY PLATEAU EARLY THIS
MORNING. WEB CAMS SUGGEST A DUSTING TO AN INCH COMMON ACROSS THE
W MTNS AS OF 07Z. APPROACH OF SFC RIDGE/FALLING INVERSION HGTS
WILL CAUSE SKIES TO CLEAR ACROSS SOUTHERN PA TOWARD DAWN AND -SHSN
TO TAPER OFF OVER ALL BUT THE N TIER COUNTIES BY 12Z. 00Z NCAR
MESO ENSEMBLE OUTPUT SUGGESTS ADDITIONAL ACCUMS BTWN 06Z-12Z WILL
LIKELY RANGE FROM 1-2 INCHES OVR THE SNOWBELT OF NW WARREN
COUNTY...TO NOTHING SOUTHEAST OF ST MARYS/COUDERSPORT.
&&
.SHORT TERM /8 AM THIS MORNING THROUGH 6 PM TUESDAY/...
BEST LAKE EFFECT SNOW THREAT MONDAY MORNING WILL LIFT NORTH OF THE
REGION...AS BLYR FLOW BACKS TO THE WSW. STILL...NW WARREN CO
COULD SEE AN ADDITIONAL INCH OR SO BTWN 12Z-18Z.
RIDGE OF HIGH PRES WILL BUILD IN FROM THE OHIO VALLEY ON
MONDAY...BRINGING MSUNNY SKIES ACROSS SOUTHERN PA AND DIMINISHING
LE SNOW SHOWERS ACROSS THE NW MTNS. ENS MEAN 8H TEMPS OF JUST -16C
SHOULD TRANSLATE TO MAX TEMPS FROM THE UTEENS ACROSS THE NW
MTNS...TO THE L30S OVR THE LOWER SUSQ VALLEY.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
DID NOT CHANGE MUCH FOR THIS PERIOD.
CLIPPER WILL PASS NORTH OF PA ON TUESDAY. THE COMBINATION OF
STRONG HEIGHT FALLS AND WARM ADVECTION AHEAD OF THIS SYSTEM SHOULD
RESULT IN SEVERAL BANDS OF SNOW SHOWERS AHEAD AND ALONG THE
TRAILING COLD FRONT. WHILE TEMPERATURES SHOULD CLIMB INTO THE MID
TO UPPER 30S ACROSS THE SE...THE COMBINATION OF COLD AIR ALOFT AND
DRY AIR SHOULD RESULT IN AT LEAST A FEW FLURRIES...LIGHT SNOW
SHOWERS...ACROSS THE SE.
FOR LATER TUESDAY NIGHT INTO WED...AS WINDS SHIFT MORE TO THE
WEST THEN W TO NW LATER ON...NW AREAS AND THE HIGHLANDS SHOULD
SEE SOME SNOW. DID UP THE AMTS ACROSS THE NW. LOOKS LIKE THE
HEAVIEST WOULD BE NW OF OUR AREA.
ALSO DID ADJUST AMTS UP SOME FOR WED...MAY NEED TO ADJUST MORE
AS WE GET CLOSER TO THE EVENT.
ANOTHER WEAK SYSTEM FOR THU...HARD TO SEE MUCH FROM THIS.
TEMPERATURES SHOULD SLOWLY MODERATE SOME BY LATE WEEK.
HAVE SOME LOW CHC POPS IN FOR SAT.
00Z EC HAS A SYSTEM TO THE SOUTH. 12Z GFS TRENDING TOWARD THE
LAKES WITH A WEAK SYSTEM. A LOT OF SPREAD...MOST LIKELY WILL
GET A COMBO OF WEAK SYSTEMS.
&&
.AVIATION /07Z MONDAY THROUGH FRIDAY/...
BANDS OF PRECIPITATION CONTINUE ACROSS THE CENTRAL MOUNTAINS AND
THROUGH THE NORTHERN HALF OF CENTRAL PA CURRENTLY AND THROUGH 09Z.
EXPECT THAT AS THE TROUGH MOVES TO THE NORTH THE BAND OF
PRECIPITATION WILL MOVE NORTHWARD...WITH THE IFR INDUCING
CONDITIONS ENDING BETWEEN 07Z TO 09Z AS THE LATEST HRRR CONTINUES
TO SHOW THE PRECIPITATION BANDS WILL FADE AS THE TROUGH MOVES TO
THE NORTHEAST. EXPECT THAT SNOW BANDS WILL DISSIPATE AFTER 09Z.
OVERALL MVFR CONDITIONS WILL CONTINUE OVERNIGHT AT BFD...WITH IFR
VSBYS AT TIMES IN THE HEAVIER BANDS OF PRECIPITATION.
DOWNSLOPE FLOW HAS BROUGHT CIG IMPROVEMENTS TO VFR OVER THE
EAST...WHILE UPSLOPE AND PROXIMITY TO UPPER LOW WILL KEEP CIG
RESTRICTIONS IN PLACE OVER THE WEST.
CIG RESTRICTIONS SHOULD LIFT BY EARLY MORNING WITH MAINLY VFR
TOMORROW.
OUTLOOK...
MON...A FEW LOCALIZED BANDS OF LOW CIGS AND VSBYS IN SNOW SHOWERS
ACROSS THE LAUREL HIGHLANDS AND NW MTNS POSSIBLE.
OTHERWISE...QUITE BREEZY WITH NO WIDESPREAD SIG WX RESTRICTIONS
EXPECTED.
TUE...CIG REDUCTIONS LIKELY NW HALF INTO PORTIONS OF CENTRAL MTNS IN
LIGHT SNOW. VFR SE.
WED-THU...CIG REDUCTIONS LIKELY NW HALF IN SNOW SHOWERS. VFR
ELSEWHERE.
FRI...FAIR.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...FITZGERALD
NEAR TERM...FITZGERALD
SHORT TERM...DEVOIR
LONG TERM...MARTIN
AVIATION...DEVOIR/CERU
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1205 AM EST MON JAN 11 2016
.SYNOPSIS...
MUCH COLDER AIR IS RUSHING INTO THE REGION. SNOW WILL ACCUMULATE
OVER PORTIONS OF THE ALLEGHENIES. THE NORTHWEST MOUNTAINS ARE MOST
LIKELY TO SEE A FEW INCHES OF ACCUMULATION BY LATE TONIGHT. A DEEP
UPPER LEVEL TROUGH WILL PIVOT THROUGH THE NORTHEAST CONUS THIS
WEEK...WITH AN ARCTIC FRONT LIKELY TO CROSS THE COMMONWEALTH ON
TUESDAY. THE UPPER TROUGH WILL LIFT OUT OF THE REGION BY THE END
OF THE WEEK.
&&
.NEAR TERM /UNTIL 8 AM MONDAY MORNING/...
945 PM UPDATE...
GUSTS ARE SLOWLY DECREASING AND HAVE BEEN BELOW ADVY LEVELS FOR AT
LEAST AN HOUR. THE GRADIENT WILL SLACKEN A BIT OVERNIGHT. HAVE
CANNED THE ADVY. ALL OTHER ELEMENTS ARE WELL ON-TRACK. MINOR
TWEAKS TO SKY COVER WERE MADE WITH AN EYE TOWARD THE EXPANSE OF
LOW CLOUDS TO THE WEST...AND AN ALLOWANCE FOR THE DOWNSLOPE IN THE
SE.
7 PM UPDATE...
WIND GUSTS HAVE DIMINISHED OVER MOST OF THE AREA. ONLY THE HIGHER
ELEVATIONS IN THE LAURELS AND NC MTNS SHOULD SEE ANY GUSTS OVER
40KTS FOR THE REST OF THE NIGHT. A GAP WIND/FUNNELING IN PLACES
LIKE MARTINSBURG /KAOO/ COULD INCREASE THE GUSTS LOCALLY...BUT
THOSE SHOULD BE INFREQUENT AND HAVE DROPPED THE WIND ADVY FOR MUCH
OF THE AREA. SNOW SHOWERS PROBABLY HAVING A TOUGH TIME
ACCUMULATING JUST YET WITH THE STRONG WIND AND THE BANDING NOT
QUITE SET UP. RADAR STILL LOOKS LIKE THERE IS LOTS OF
INSTABILITY/CELLULAR RETURNS OVER OH/WRN PA. WILL KEEP MENTIONS OF
SHSN/FLURRIES PAST MIDNIGHT IN THE NW HALF OF THE AREA. A DUSTING
CAN/T BE RULED OUT AS FAR SE AS THE FARM SHOW COMPLEX...BUT
DOWNSLOPING WILL KEEP ANY MEASURABLE SNOW TO PLACES NW OF THE OL
AOO-UNV-IPT LINE.
PREV...
COLD FRONT PUSHING THROUGH CENTRAL MOUNTAINS PRESENTLY...WITH RAIN
SHOWERS QUICKLY CHANGING TO SNOW SHOWERS. SNOW WAS FALLING AT NWS
EMPLOYEE HOME WITH AIR TEMPERATURE OF 47...AN INDICATION OF HOW
COLD THINGS ARE GETTING JUST A FEW THOUSAND FEET ABOVE. IT WILL
TAKE A WHILE TO COOL THINGS DOWN NEAR THE GROUND...AND MOST AREAS
WILL SEE LITTLE TO NO ACCUMULATION OUTSIDE OF THE WEST CENTRAL AND
NORTHWEST MOUNTAINS WHICH WILL SEE A COATING TO A FEW INCHES IN
MOST SPOTS.
BIGGEST CONCERN IS FAVORABLE SETUP FOR HIGH POST-FRONTAL WINDS
THROUGH LATE TONIGHT...WITH INTENSIFYING SFC LOW TRACKING ACROSS
THE E GRT LKS...STRONG SUBSIDENCE AND ISSALLOBARIC COUPLET
PASSAGE. BUFKIT SOUNDINGS SUPPORT WGUSTS BTWN 45-50KTS ACROSS THE
ALLEGHENY PLATEAU/CENTRAL MTNS LATE TONIGHT AND THIS EVENING...AND
RETAINED WIND ADVISORY. ELSEWHERE...PROLONGED GUSTY CONDITIONS
EXPECTED WITH WIDESPREAD 25 TO 35 MPH AND GUSTS TO 45 MPH THROUGH
LATE TONIGHT ALONG AND BEHIND THE FRONT.
STRONG/GUSTY WINDS WILL ONLY SLOWLY SUBSIDE OVERNIGHT...AS REGION
REMAINS WITHIN TIGHT PRES GRADIENT SOUTH OF INTENSIFYING SFC LOW.
BUFKIT SOUNDINGS INDICATE OCNL GUSTS NEAR ADVISORY CRITERIA COULD
LAST MUCH OF THE NIGHT ACROSS THE W MTNS. PLUMMETING TEMPS...COMBINED
WITH THE GUSTY WINDS...WILL LIKELY CREATE WCHILLS NEAR ZERO ACROSS
THE W MTNS BY MON AM.
&&
.SHORT TERM /8 AM MONDAY MORNING THROUGH 6 PM MONDAY/...
BEST LAKE EFFECT SNOW THREAT MONDAY MORNING WILL LIFT NORTH OF THE
REGION...WITH SEVERAL INCHES LIKELY SETTING UP NORTH OF THE PA/NY
BORDER. STILL...NORTHWEST MOUNTAINS SHOULD SEE A COATING TO A FEW
INCHES FROM THIS. FALLING INVERSION HEIGHT WILL LIMIT SNOW
POTENTIAL ON MONDAY. NCAR MESO ENSEMBLE OUTPUT STILL SUPPORTS
TOTAL ACCUMS NR 4 INCHES ACROSS NW WARREN CO BY LATE MON
MORNING...BUT LIKELY NOT MEETING ADVISORY CRITERIA OF 3+ IN 12HRS.
RIDGE OF HIGH PRES WILL BUILD IN FROM THE OHIO VALLEY ON
MONDAY... BRINGING MSUNNY SKIES ACROSS SOUTHERN PA AND
DIMINISHING LE SNOW SHOWERS ACROSS THE NW MTNS. ENS MEAN 8H TEMPS
OF JUST -16C SHOULD TRANSLATE TO MAX TEMPS FROM ARND 20F ACROSS
THE NW MTNS...TO ARND 30F OVR THE LOWER SUSQ VALLEY.
&&
.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
DID NOT CHANGE MUCH FOR THIS PERIOD.
CLIPPER WILL PASS NORTH OF PA ON TUESDAY. THE COMBINATION OF
STRONG HEIGHT FALLS AND WARM ADVECTION AHEAD OF THIS SYSTEM SHOULD
RESULT IN SEVERAL BANDS OF SNOW SHOWERS AHEAD AND ALONG THE
TRAILING COLD FRONT. WHILE TEMPERATURES SHOULD CLIMB INTO THE MID
TO UPPER 30S ACROSS THE SE...THE COMBINATION OF COLD AIR ALOFT AND
DRY AIR SHOULD RESULT IN AT LEAST A FEW FLURRIES...LIGHT SNOW
SHOWERS...ACROSS THE SE.
FOR LATER TUESDAY NIGHT INTO WED...AS WINDS SHIFT MORE TO THE
WEST THEN W TO NW LATER ON...NW AREAS AND THE HIGHLANDS SHOULD
SEE SOME SNOW. DID UP THE AMTS ACROSS THE NW. LOOKS LIKE THE
HEAVIEST WOULD BE NW OF OUR AREA.
ALSO DID ADJUST AMTS UP SOME FOR WED...MAY NEED TO ADJUST MORE
AS WE GET CLOSER TO THE EVENT.
ANOTHER WEAK SYSTEM FOR THU...HARD TO SEE MUCH FROM THIS.
TEMPERATURES SHOULD SLOWLY MODERATE SOME BY LATE WEEK.
HAVE SOME LOW CHC POPS IN FOR SAT.
00Z EC HAS A SYSTEM TO THE SOUTH. 12Z GFS TRENDING TOWARD THE
LAKES WITH A WEAK SYSTEM. A LOT OF SPREAD...MOST LIKELY WILL
GET A COMBO OF WEAK SYSTEMS.
&&
.AVIATION /04Z MONDAY THROUGH FRIDAY/...
BANDS OF PRECIPITATION CONTINUE ACROSS THE CENTRAL MOUNTAINS AND
THROUGH THE NORTHERN HALF OF CENTRAL PA CURRENTLY AND THROUGH 09Z.
EXPECT THAT AS THE TROUGH MOVES TO THE NORTH THE BAND OF
PRECIPITATION WILL MOVE NORTHWARD...WITH THE IFR INDUCING
CONDITIONS ENDING BETWEEN 07Z TO 09Z AS THE LATEST HRRR CONTINUES
TO SHOW THE PRECIPITATION BANDS WILL FADE AS THE TROUGH MOVES TO
THE NORTHEAST. EXPECT THAT SNOW BANDS WILL DISSIPATE AFTER 09Z.
OVERALL MVFR CONDITIONS WILL CONTINUE OVERNIGHT AT BFD...WITH IFR
VSBYS AT TIMES IN THE HEAVIER BANDS OF PRECIPITATION.
DOWNSLOPE FLOW HAS BROUGHT CIG IMPROVEMENTS TO VFR OVER THE
EAST...WHILE UPSLOPE AND PROXIMITY TO UPPER LOW WILL KEEP CIG
RESTRICTIONS IN PLACE OVER THE WEST.
CIG RESTRICTIONS SHOULD LIFT BY EARLY MORNING WITH MAINLY VFR
TOMORROW.
OUTLOOK...
MON...A FEW LOCALIZED BANDS OF LOW CIGS AND VSBYS IN SNOW SHOWERS
ACROSS THE LAUREL HIGHLANDS AND NW MTNS POSSIBLE.
OTHERWISE...QUITE BREEZY WITH NO WIDESPREAD SIG WX RESTRICTIONS
EXPECTED.
TUE...CIG REDUCTIONS LIKELY NW HALF INTO PORTIONS OF CENTRAL MTNS IN
LIGHT SNOW. VFR SE.
WED-THU...CIG REDUCTIONS LIKELY NW HALF IN SNOW SHOWERS. VFR
ELSEWHERE.
FRI...FAIR.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DEVOIR/MARTIN
NEAR TERM...DANGELO/DEVOIR
SHORT TERM...DEVOIR
LONG TERM...MARTIN
AVIATION...DEVOIR/CERU
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
310 AM CST MON JAN 11 2016
.SHORT TERM (TODAY THROUGH TUESDAY)...
MAIN HEADLINE IN THE SHORT TERM WILL BE THE ISOLATED POCKETS OF
FREEZING TEMPERATURES ACROSS THE HIGHER ELEVATIONS OF BEXAR AND INTO
PORTIONS OF COASTAL PLAINS WHERE LESS CLOUDS RESIDE. OUTSIDE OF THIS
MARGINAL HAZARD - EXPECT VERY LOW END RAIN CHANCES FOR THE FAR
SOUTHEAST COASTAL PLAINS THIS EVENING INTO EARLY TUESDAY MORNING.
MOST LOCATIONS WILL NOT SEE ANY RAIN WITH PARTLY TO MOSTLY CLOUDY
SKIES TODAY.
SYNOPTIC PATTERN VIA WATER VAPOR CHANNELS AND RAP ANALYSIS DEPICTS
SPLIT FLOW BEGINNING TO DEVELOP AS THE SOUTHERN JET-STREAM BRANCH
BECOMES MORE ACTIVE. A HIGHLY POSITIVELY-TILTED SHORTWAVE TROUGH IS
OVER NEW MEXICO AND THIS, ALONG WITH WEAK MID-LEVEL DIVERGENCE, IS
ALLOWING FOR ELEVATED ECHOS TO APPEAR ON RADAR. THIS PRECIPITATION
IS NOT REACHING THE GROUND BUT THE RESULTANT CLOUDS ARE KEEPING
TEMPERATURES FROM BOTTOMING TO THEIR FULL POTENTIAL. BOERNE IS
CURRENTLY JUST BELOW THE FREEZING MARK AND COASTAL PLAIN
LOCATIONS WITHIN THE FREEZE WARNING ARE UNDER CLEAR SKIES AND
HEADING THAT DIRECTION. THE FREEZE WARNING IS IN EFFECT FROM 4AM
THROUGH 8AM AND TEMPERATURES ARE NOT EXPECTED TO BE AT FREEZING
FOR VERY LONG.
HAVE DELAYED THE ONSET OF ANY LIGHT RAIN/DRIZZLE UNTIL THIS EVENING
ACROSS THE FAR SOUTHEAST COASTAL PLAINS. OVERALL AVAILABLE MOISTURE
APPEARS TO BE MORE MEAGER THAN EVEN THE ALREADY LOW VALUES
ADVERTISED YESTERDAY. A WEAK BOUNDARY/PACIFIC FRONT WILL PUSH
THROUGH TUESDAY MORNING BRINING DRIER AIR IN THE SFC-700MB LAYER.
AMPLE SUN IS EXPECTED TUESDAY AFTERNOON AND A NICE WARM UP IS
EXPECTED INTO THE LOW 60S.
&&
.LONG TERM (WEDNESDAY THROUGH NEXT SUNDAY)...
DESPITE AN ACTIVE SOUTHERN JET-STREAM BRANCH AND SEVERAL PACIFIC
FRONTS EXPECTED TO MOVE THROUGH THE REGION THIS PERIOD...OVERALL
RAIN AMOUNTS REMAIN LOW. NO SIGNIFICANT HAZARDS APPEAR TO BE ON TAP
AT THIS POINT GIVEN THE MIS-ALIGNING OF LIMITED MOISTURE POOLING AND
DEEPER FORCING MECHANISMS. A GRADUAL WARM UP IS ANTICIPATED INTO THE
MID AND EVEN UPPER 60S BY THE END OF THE WEEK.
GLOBAL MODELS REMAIN AT ODDS WITH EACH OTHER CONCERNING THE
DIFFICULT PROGNOSTICATION OF THE SPLIT JET-STREAM FLOW. HAVE
FOLLOWED MORE OF A 33/33/33 WEIGHTED FORECAST WITH THE GFS/EC/GEM
THIS PACKAGE AS THE EC/GEM TEND TO HAVE MORE SUPPORT FROM THE NAM
AND UKMET MODELS IN MEDIUM AND LONG RANGE.
BY MID WEEK...ENERGY FROM THE CURRENT SHORTWAVE TROUGH WILL GET
TRAPPED/CUT-OFF OVER MEXICO AND IT WILL BE THIS COMPLEX THAT WILL
GIVE LIFT TO THE LIMITED MOISTURE IN PLACE LATE WEDNESDAY INTO
THURSDAY. GFS IS QUICKER AS IT PHASES SOME NORTHERN STREAM ENERGY IN
BUT EC/GEM/NAM ARE SLOWER. HAVE LEANED SLOWER AND PLACED 20-40% RAIN
CHANCES FROM WEST TO EAST FROM THE 35 CORRIDOR TO THE COASTAL
PLAINS. BEST TIME-FRAME FOR RAIN WILL BEGIN LATE WEDNESDAY NIGHT
THROUGH THURSDAY AFTERNOON. WESTERN AREAS STILL APPEAR TOO DRY FOR
ANY ACCUMULATING RAINFALL. A PACIFIC FRONT WILL PUSH THROUGH THE
REGION BY EARLY FRIDAY AND END RAIN CHANCES AS THE AFOREMENTIONED CUT-
OFF ENERGY PHASES WITH A STRONGER PASSING NORTHERN STREAM TROUGH.
WITH THE BRISK H5 FLOW, THE NEXT TROUGH APPROACHES THE REGION BY
SATURDAY. PWATS WILL BE 0.3-0.4" AND IT WILL BE DIFFICULT TO HAVE
PRECIPITATION REACH THE GROUND. HAVE OPTED FOR A DRY FORECAST FOR
NOW BUT CLOUDS WILL CERTAINLY BE ON THE INCREASE SATURDAY. BY
SUNDAY...THE TROUGH WILL SHIFT EAST AND USHER IN A POSSIBLE HYBRID
PACIFIC/BACKDOOR FRONT FROM THE NORTH. THIS SHOULD KEEP US DRY
SUNDAY BUT YET ANOTHER SYSTEM WILL BE ON ITS HEELS THAT APPEARS
STRONGER AND A BETTER CHANCE OF RAIN APPEARS POSSIBLE NEXT TUESDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 53 37 63 40 62 / 10 - 0 0 10
AUSTIN BERGSTROM INTL AIRPORT 53 34 62 36 61 / 10 - 0 0 10
NEW BRAUNFELS MUNI AIRPORT 54 35 63 39 61 / 10 - 0 - 10
BURNET MUNI AIRPORT 51 34 61 37 60 / 10 0 0 0 -
DEL RIO INTL AIRPORT 55 36 62 40 61 / - 0 0 0 0
GEORGETOWN MUNI AIRPORT 52 34 61 37 60 / 10 - 0 0 10
HONDO MUNI AIRPORT 54 34 62 39 60 / 10 - 0 - 10
SAN MARCOS MUNI AIRPORT 54 36 62 38 60 / 10 - 0 - 10
LA GRANGE - FAYETTE REGIONAL 55 38 62 40 62 / 10 10 0 - 10
SAN ANTONIO INTL AIRPORT 54 37 63 40 61 / 10 - 0 - 10
STINSON MUNI AIRPORT 55 38 63 41 61 / 10 - 0 - 10
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
FREEZE WARNING UNTIL 8 AM CST THIS MORNING FOR THE FOLLOWING
COUNTIES: ATASCOSA...BEXAR...DE WITT...FRIO...KARNES...WILSON.
&&
$$
MESOSCALE/AVIATION...OAKS
SYNOPTIC/GRIDS...ALLEN
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
648 AM EST MON JAN 11 2016
.SYNOPSIS...
A WESTERLY FLOW OF COLD AND MOIST AIR WILL BRING SCATTERED SNOW
SHOWERS AND FLURRIES TO A LARGE PART OF CENTRAL NEW YORK AND
NORTHEAST PENNSYLVANIA TODAY. A LOW PRESSURE SYSTEM WILL TRACK
ACROSS THE GREAT LAKES TONIGHT TO OFF THE NEW ENGLAND COAST BY
TUESDAY NIGHT. THIS SYSTEM WILL BRING A WIDESPREAD INCH OR TWO OF
SNOW TO THE REGION TUESDAY. AFTER THIS SYSTEM PASSES BY, HEAVY
LAKE EFFECT SNOW WILL BE POSSIBLE ALONG THE THRUWAY CORRIDOR FROM
SYRACUSE TO UTICA AND ROME TUESDAY NIGHT AND WEDNESDAY. ELSEWHERE
EXPECT SCATTERED SNOW SHOWERS AND FLURRIES WITH ONLY LIGHT
ACCUMULATIONS THROUGH WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
DROPPED WIND ADVISORY AS WINDS WILL CONTINUE TO WEAKEN. SYR STILL
GUSTING WITH A PEAK WIND AT 519 AM OF 44 KNOTS. REST OF STATIONS
AROUND NORTH CENTRAL NY HAVE SEEN WINDS WEAKEN CONSIDERABLY WITH
PEAK WINDS BARELY 30 KNOTS. MADE SOME MINOR ADJUSTMENTS TO POPS
ESPECIALLY FOR WESTERN STEUBEN CO WHERE I COULD SEE A FEW INCHES
OF SNOW TODAY. OTHERWISE NO MAJOR CHANGES TO PREVIOUS FORECAST.
PREVIOUS DISCUSSION BELOW...
RADAR IMAGERY SHOWS MAIN LAKE EFFECT SNOW BAND NORTH OF ONEIDA
COUNTY. THE KTYX VAD WIND PROFILE IS SHOWING A 260 DEGREE FLOW
FROM 3 TO 8 THOUSAND FEET ABOVE SEA LEVEL AND WAS DIRECTING THE
LAKE EFFECT SNOWS TO OUR NORTH. THE 00Z RGEM, 00Z NAM12,
WRF_ARW,AND HRRR WERE ALL KEEPING THIS BAND TO OUR NORTH THROUGH
THE DAY. THE ONLY HI RES MODEL THAT WAS BRINGING THE BAND INTO
NORTHERN ONEIDA COUNTY TODAY WAS THE WRF_NMM. THE MODELS HAVE
TRENDED NORTH WITH THE BAND FROM YESTERDAY AND CURRENT RADAR
INDICATES THAT THIS WILL BE THE CASE SO WILL KEEP SIGNIFICANT
SNOWS OUT OF OUR FORECAST AREA TODAY. LAKE EFFECT SNOW WARNINGS
ARE OUT TO OUR NORTH AND LOOK GREAT. THE REST OF THE FORECAST AREA
WAS SEEING SCATTERED SNOW SHOWERS AND FLURRIES ON A WEST TO
SOUTHWEST FLOW. NAM AND GFS SOUNDINGS ARE SHOWING VERY STEEP LOW-
LEVEL LAPSE RATES THRU THE MORNING WHICH WAS LEADING TO SOME
SMALL CAPE UNDER THE INVERSION WHICH WAS AT ABOUT 800 MB OR 5000
FEET. THIS WAS ENOUGH TO ORGANIZE SOME SNOW SHOWERS AND FLURRIES.
MUCH OF THIS SMALL CAPE WAS IN THE MAX GROWTH REGIME FOR ICE
CRYSTALS. AS THE DAY PROGRESSES THE BOUNDARY LAYER WILL CONTINUE
TO BE DRYING AND I EXPECT THE ACVTY TO MOVE BACK CLOSER TO THE
LAKES. SO I HAVE SCATTERED SNOW SHOWERS AND FLURRIES DIMINISHING
SOME TO THE WEST.
AS FOR WINDS SYR JUST GUSTED TO 40 KNOTS AND RME WAS STILL HITTING 38
KNOTS WHICH IS CLOSE TO ADVY CRITERIA. WILL HOLD ONTO WIND ADVY
UNTIL WINDS MARKEDLY DROP OFF.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
FOR TONIGHT AND TUESDAY...ALL MODELS SHOW A CLIPPER-TYPE SYSTEM
TRACK FROM THE GREAT LAKES REGION TONIGHT TO NORTH OF LAKE
ONTARIO BY TUESDAY EVENING AND THEN TO OFF THE NEW ENGLAND COAST
BY WEDNESDAY MORNING. AS THIS SYSTEM APPROACHES NEW YORK AND
PENNSYLVANIA THE LOW-LEVEL WINDS WILL BACK TO THE SOUTHWEST AND
SEND ANY RESIDUAL LAKE EFFECT SNOW SHOWERS TO THE NORTH OR CUT
THEM OFF FROM THEIR SOURCE REGION. SO I DRY OUT TONIGHT IN OUR
FORECAST. ALL SYNOPTIC SCALE MODELS SHOW A REGION OF WARM AIR
ADVECTION (OR ISENTROPIC LIFT IF YOU PREFER THAT COORDINATE
SYSTEM) ACROSS NEW YORK AND PENNSYLVANIA TUESDAY MORNING. HOWEVER
THIS SYSTEM WILL BE MOISTURE STARVED AND SOUTHWEST WINDS TEND TO
DOWNSLOPE ACROSS A WIDE AREA OF CENTRAL NY AND NORTHEAST PA. THE
EXCEPTIONS ARE THE CATSKILLS AND SOUTHERN TUG HILL PLATEAU AND
ALLEGHENIES OF WESTERN NY. THEN AS THE CLIPPER TRACKS TO OUR
NORTHEAST TUESDAY AFTERNOON THERE IS SOME LAKE ENHANCED COLD FRONTAL
SNOW SHOWERS THAT WILL ADD A BIT MORE TO THE TOTAL ACCUMULATIONS.
FOR NOW WE SEE MOST AREAS GETTING AROUND 1 INCH WITH LOCALLY 2-3
INCHES IN THE CATSKILLS TO UPPER MOHAWK AND SOUTHERN TUG HILL
PLATEAU AND WESTERN STEUBEN COUNTY.
AFTER THIS SYSTEM PASSES TUESDAY EVENING, THE INVERSION CLIMBS TO
ALMOST 700 MB AND THE MEAN WIND IN THIS LAYER IS FROM 280-290
DEGREES. BOTH THE GFS AND NAM MODEL SOUNDINGS BETWEEN ABOUT 6Z-9Z
AND 18Z-21Z WEDNESDAY INDICATE UPWARD MOTION IN THE MAX ICE
CRYSTAL GROWTH REGIME SUGGESTING SIGNIFICANT SNOW GROWTH
POTENTIAL. THE 850 MB TEMPERATURES WERE AROUND -18C WHICH GIVES AT
LEAST A 23C DIFFERENTIAL WHICH IS EXTREME LAKE-INDUCED
INSTABILITY. THE ONLY UNCERTAINTY IS THE EXACT WIND DIRECTION
WHICH IS STILL SOMEWHAT UNCERTAIN. IT LOOKS LIKE AT LEAST 8-12
INCHES OF SNOW TUESDAY NGT AND WEDNESDAY AND POSSIBLY MORE
SOMEWHERE IN ONONDAGA, MADISON OR ONEIDA COUNTIES. THIS COULD BE A
BIG EVENT FOR THE THRUWAY CORRIDOR, THE FIRST OF THIS LATE
EVOLVING WINTER SEASON. ISSUED LAKE EFFECT SNOW WATCHES FOR
TUESDAY NIGHT AND WEDNESDAY TO COVER FOR ONONDAGA, ONEIDA AND
MADISON COUNTIES.
ALL LAKE EFFECT ACTIVITY WINDS DOWN WED NGT AS FLOW BACKS MORE
SOUTHWESTERLY.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
WIND FIELD WILL LIKELY WAVER BACK AND FORTH BETWEEN NW AND WEST
THROUGH THURSDAY AND FRIDAY...BUT WITH ENOUGH OF A CONTINUOUS
INFLUX OF COLD AIR TO KEEP THE LAKE BANDS GOING. AT THIS TIME IT
APPEARS THE WED THROUGH THURSDAY NIGHT TIME PERIOD APPEARS TO BE
THE MOST FAVORABLE FOR SIGNIFICANT LAKE EFFECT SNOW ACCUMULATIONS
ACROSS THE NRN COUNTIES. WILL NEED TO KEEP AN EYE ON THIS EVENT AS
IT DEVELOPS THROUGH THE WEEK AND MODEL GUIDANCE GETS A BETTER
HANDLE ON THE WIND TRAJECTORIES.
A WEAK RIDGE OF HIGH PRESSURE EVENTUALLY BUILDS IN FROM THE NORTH
ON FRIDAY AND ALLOWS THE LES TO END. THE PATTERN IS EXPECTED TO
REMAIN ACTIVE HOWEVER INTO THE WEEKEND AS ANOTHER STORM SYSTEM IS
FORECAST TO DEVELOP OVER THE OHIO VALLEY AND LIFT INTO THE NE
THROUGH THE WEEKEND. IT IS TOO EARLY TO DETERMINE THE EXACT NATURE
OF THIS SYSTEM...BUT ALL SIGNS POINT TO A WINTRY STORM SYSTEM.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
ARCTIC AIR IS OVERSPREADING THE REGION...TOUCHING OFF LOCALIZED LAKE
EFFECT SNOW SHOWERS-FLURRIES IN SOUTHERN TIER OF NY. IN GENERAL
THOUGH PREDOMINANTLY VFR WITH GUSTY WEST WINDS THROUGH THE COMING
DAY. NARROW BANDS OF INTERMITTENT MVFR VIS SNOW SHOWERS WILL VISIT
KBGM-KITH THIS MORNING. BRIEF IFR VIS NOT OUT OF THE
QUESTION...BUT OVERALL AMOUNT OF DRY AIR WILL MAKE THAT THE
EXCEPTION AND NOT THE RULE. LAKE ONTARIO SNOW BANDS WILL BE A NON-
ISSUE...STAYING NORTH OF KSYR- KRME. WESTERLY WINDS 15-2O KTS WITH
GUST 25-3O KTS THIS MORNING THROUGH MID AFTERNOON...PERHAPS A
TOUCH HIGHER FOR KSYR...THEN DIMINISHING WHILE BACKING SW-SSW
TONIGHT. CLIPPER SYSTEM WILL ZIP INTO THE AREA TUESDAY MORNING.
TYPE OF SNOW APPEARS FAVORABLE FOR AT LEAST IFR VIS...REACHING
KSYR-KELM-KITH JUST PRIOR TO DAYBREAK AND SOON TO BE FOLLOWED BY
REMAINDER OF TERMINALS.
.OUTLOOK...
TUE...CLIPPER SYSTEM WILL PASS WITH WINDOW OF WIDESPREAD -SN AND
MVFR-IFR RESTRICTIONS.
TUE NGT-WED...LAKE SHSN MAINLY NY TERMINALS. VERY RESTRICTIVE
CONDITIONS POSSIBLE AT TIMES LATE TUE NGT INTO WED FOR KSYR-KRME
IF HEAVIER LAKE ONTARIO BANDS MANAGE TO PASS OVER TERMINALS.
WED NGT-THU-THU NGT...LAKE EFFECT SHSN AND ASSOCIATED
INTERMITTENT RESTRICTIONS MAINLY NY TERMINALS.
FRI...MAINLY VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...LAKE EFFECT SNOW WATCH FROM TUESDAY EVENING THROUGH WEDNESDAY
EVENING FOR NYZ009-018-036-037.
&&
$$
SYNOPSIS...DJN
NEAR TERM...DJN
SHORT TERM...DJN
LONG TERM...BJT/MDP
AVIATION...MDP
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
604 AM EST MON JAN 11 2016
.SYNOPSIS...
A WESTERLY FLOW OF COLD AND MOIST AIR WILL BRING SCATTERED SNOW
SHOWERS AND FLURRIES TO A LARGE PART OF CENTRAL NEW YORK AND
NORTHEAST PENNSYLVANIA TODAY. A LOW PRESSURE SYSTEM WILL TRACK
ACROSS THE GREAT LAKES TONIGHT TO OFF THE NEW ENGLAND COAST BY
TUESDAY NIGHT. THIS SYSTEM WILL BRING A WIDESPREAD INCH OR TWO OF
SNOW TO THE REGION TUESDAY. AFTER THIS SYSTEM PASSES BY, HEAVY
LAKE EFFECT SNOW WILL BE POSSIBLE ALONG THE THRUWAY CORRIDOR FROM
SYRACUSE TO UTICA AND ROME TUESDAY NIGHT AND WEDNESDAY. ELSEWHERE
EXPECT SCATTERED SNOW SHOWERS AND FLURRIES WITH ONLY LIGHT
ACCUMULATIONS THROUGH WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
DROPPED WIND ADVISORY AS WINDS WILL CONTINUE TO WEAKEN. SYR STILL
GUSTING WITH A PEAK WIND AT 519 AM OF 44 KNOTS. REST OF STATIONS
AROUND NORTH CENTRAL NY HAVE SEEN WINDS WEAKEN CONSIDERABLY WITH
PEAK WINDS BARELY 30 KNOTS. MADE SOME MINOR ADJUSTMENTS TO POPS
ESPECIALLY FOR WESTERN STEUBEN CO WHERE I COULD SEE A FEW INCHES
OF SNOW TODAY. OTHERWISE NO MAJOR CHANGES TO PREVIOUS FORECAST.
PREVIOUS DISCUSSION BELOW...
RADAR IMAGERY SHOWS MAIN LAKE EFFECT SNOW BAND NORTH OF ONEIDA
COUNTY. THE KTYX VAD WIND PROFILE IS SHOWING A 260 DEGREE FLOW
FROM 3 TO 8 THOUSAND FEET ABOVE SEA LEVEL AND WAS DIRECTING THE
LAKE EFFECT SNOWS TO OUR NORTH. THE 00Z RGEM, 00Z NAM12,
WRF_ARW,AND HRRR WERE ALL KEEPING THIS BAND TO OUR NORTH THROUGH
THE DAY. THE ONLY HI RES MODEL THAT WAS BRINGING THE BAND INTO
NORTHERN ONEIDA COUNTY TODAY WAS THE WRF_NMM. THE MODELS HAVE
TRENDED NORTH WITH THE BAND FROM YESTEDAY AND CURRENT RADAR
INDICATES THAT THIS WILL BE THE CASE SO WILL KEEP SIGNIFICANT
SNOWS OUT OF OUR FORECAST AREA TODAY. LAKE EFFECT SNOW WARNINGS
ARE OUT TO OUR NORTH AND LOOK GREAT. THE REST OF THE FORECAST AREA
WAS SEEING SCATTERED SNOW SHOWERS AND FLURRIES ON A WEST TO
SOUTHWEST FLOW. NAM AND GFS SOUNDINGS ARE SHOWING VERY STEEP LOW-
LEVEL LAPSE RATES THRU THE MORNING WHICH WAS LEADING TO SOME
SMALL CAPE UNDER THE INVERSION WHICH WAS AT ABOUT 800 MB OR 5000
FEET. THIS WAS ENOUGH TO ORGANIZE SOME SNOW SHOWERS AND FLURRIES.
MUCH OF THIS SMALL CAPE WAS IN THE MAX GROWTH REGIME FOR ICE
CRYSTALS. AS THE DAY PROGRESSES THE BOUNDARY LAYER WILL CONTINUE
TO BE DRYING AND I EXPECT THE ACVTY TO MOVE BACK CLOSER TO THE
LAKES. SO I HAVE SCATTERED SNOW SHOWERS AND FLURRIES DIMINISHING
SOME TO THE WEST.
AS FOR WINDS SYR JUST GUSTED TO 40 KNOTS AND RME WAS STILL HITTING 38
KNOTS WHICH IS CLOSE TO ADVY CRITERIA. WILL HOLD ONTO WIND ADVY
UNTIL WINDS MARKEDLY DROP OFF.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
FOR TONIGHT AND TUESDAY...ALL MODELS SHOW A CLIPPER-TYPE SYSTEM
TRACK FROM THE GREAT LAKES REGION TONIGHT TO NORTH OF LAKE
ONTARIO BY TUESDAY EVENING AND THEN TO OFF THE NEW ENGLAND COAST
BY WEDNESDAY MORNING. AS THIS SYSTEM APPROACHES NEW YORK AND
PENNSYVANIA THE LOW-LEVEL WINDS WILL BACK TO THE SOUTHWEST AND
SEND ANY RESIDUAL LAKE EFFECT SNOW SHOWERS TO THE NORTH OR CUT
THEM OFF FROM THEIR SOURCE REGION. SO I DRY OUT TONIGHT IN OUR
FORECAST. ALL SYNOPTIC SCALE MODELS SHOW A REGION OF WARM AIR
ADVECTION (OR ISENTROPIC LIFT IF YOU PREFER THAT COORDINATE
SYSTEM) ACROSS NEW YORK AND PENNSYLVANIA TUESDAY MORNING. HOWEVER
THIS SYSTEM WILL BE MOISTURE STARVED AND SOUTHWEST WINDS TEND TO
DOWNSLOPE ACROSS A WIDE AREA OF CENTRAL NY AND NORTHEAST PA. THE
EXCEPTIONS ARE THE CATSKILLS AND SOUTHERN TUG HILL PLATEAU AND
ALLEGHENIES OF WESTERN NY. THEN AS THE CLIPPER TRACKS TO OUR
NORTHEAST TUESDAY AFTERNOON THERE IS SOME LAKE ENHANCED COLD FRONTAL
SNOW SHOWERS THAT WILL ADD A BIT MORE TO THE TOTAL ACCUMULATIONS.
FOR NOW WE SEE MOST AREAS GETTING AROUND 1 INCH WITH LOCALLY 2-3
INCHES IN THE CATSKILLS TO UPPER MOHAWK AND SOUTHERN TUG HILL
PLATEAU AND WESTERN STEUBEN COUNTY.
AFTER THIS SYSTEM PASSES TUESDAY EVENING, THE INVERSION CLIMBS TO
ALMOST 700 MB AND THE MEAN WIND IN THIS LAYER IS FROM 280-290
DEGREES. BOTH THE GFS AND NAM MODEL SOUNDINGS BETWEEN ABOUT 6Z-9Z
AND 18Z-21Z WEDNESDAY INDICATE UPWARD MOTION IN THE MAX ICE
CRYSTAL GROWTH REGIME SUGGESTING SIGNIFICANT SNOW GROWTH
POTENTIAL. THE 850 MB TEMPERATURES WERE AROUND -18C WHICH GIVES AT
LEAST A 23C DIFFERENTIAL WHICH IS EXTREME LAKE-INDUCED
INSTABILITY. THE ONLY UNCERTAINITY IS THE EXACT WIND DIRECTION
WHICH IS STILL SOMEWHAT UNCERTAIN. IT LOOKS LIKE AT LEAST 8-12
INCHES OF SNOW TUESDAY NGT AND WEDNESDAY AND POSSIBLY MORE
SOMEWHERE IN ONONDAGA, MADISON OR ONEIDA COUNTIES. THIS COULD BE
A BIG EVENT FOR THE THRUWAY CORRIDOR, THE FIRST OF THIS LATE
EVOLVING WINTER SEASON. ISSUED LAKE EFFECT SNOW WATCHES FOR
TUESDAY NIGHT AND WEDNESDAY TO COVER FOR ONONDAGA, ONEIDA AND
MADISON COUNTIES.
ALL LAKE EFFECT ACTIVITY WINDS DOWN WED NGT AS FLOW BACKS MORE
SOUTHWESTERLY.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
AS THE CLIPPER LIFTS TO THE NORTH TUE NIGHT AND EARLY WED...WEAK
RIDGING WILL OCCUR ON THE BACK SIDE OF THE SYSTEM AND KEEP THE
WINDS IN A FAVORABLE NW DIRECTION FOR ANOTHER ROUND OF LAKE
EFFECT SNOW INTO CENTRAL NY. THE WIND FIELD WILL LIKELY WAVER BACK
AND FORTH BETWEEN NW AND WEST THROUGH THURSDAY AND FRIDAY...BUT
WITH ENOUGH OF A CONTINUOUS INFLUX OF COLD AIR TO KEEP THE LAKE
BANDS GOING. AT THIS TIME IT APPEARS THE WED THROUGH THURSDAY
NIGHT TIME PERIOD APPEARS TO BE THE MOST FAVORABLE FOR SIGNIFICANT
LAKE EFFECT SNOW ACCUMULATIONS ACROSS THE NRN COUNTIES. WILL NEED
TO KEEP AN EYE ON THIS EVENT AS IT DEVELOPS THROUGH THE WEEK AND
MODEL GUIDANCE GETS A BETTER HANDLE ON THE WIND TRAJECTORIES.
A WEAK RIDGE OF HIGH PRESSURE EVENTUALLY BUILDS IN FROM THE NORTH
ON FRIDAY AND ALLOWS THE LES TO END. THE PATTERN IS EXPECTED TO
REMAIN ACTIVE HOWEVER INTO THE WEEKEND AS ANOTHER STORM SYSTEM IS
FORECAST TO DEVELOP OVER THE OHIO VALLEY AND LIFT INTO THE NE
THROUGH THE WEEKEND. IT IS TOO EARLY TO DETERMINE THE EXACT NATURE
OF THIS SYSTEM...BUT ALL SIGNS POINT TO A WINTRY STORM SYSTEM.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
ARCTIC AIR IS OVERSPREADING THE REGION...TOUCHING OFF LOCALIZED LAKE
EFFECT SNOW SHOWERS AND ASSOCIATED BRIEF RESTRICTIONS. IN GENERAL
THOUGH PREDOMINANTLY VFR AND WITH GUSTY WEST WINDS THROUGH THE COMING
DAY. NARROW BANDS OF INTERMITTENT MVFR-IFR VIS SNOW SHOWERS WILL
COME OVER FROM LAKE ERIE FIRST FOR KELM DURING PREDAWN
HOURS...LIFTING- EXTENDING TO KBGM TOWARDS DAWN...THEN UP TO KITH
MID-TO-LATE MORNING. LAKE ONTARIO SNOW BANDS WILL BE A NON-
ISSUE...STAYING NORTH OF KSYR-KRME. WESTERLY WINDS 15-2O KTS WITH
GUST 25-3O KTS THIS MORNING THROUGH MID AFTERNOON...PERHAPS A
TOUCH HIGHER FOR KSYR...THEN DIMINISHING WHILE BACKING
SOUTHWESTERLY INTO THIS EVENING.
.OUTLOOK...
TUE/TUE NGT...CLIPPER SYSTEM WITH SHOT OF WIDESPREAD -SN AND
RESTRICTIONS TUE...THEN LAKE SHSN MAINLY NY TERMINALS TUE NGT.
WED/THU...LAKE EFFECT SHSN AND ASSOCIATED INTERMITTENT
RESTRICTIONS MAINLY NY TERMINALS.
FRI...MAINLY VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...LAKE EFFECT SNOW WATCH FROM TUESDAY EVENING THROUGH WEDNESDAY
EVENING FOR NYZ009-018-036-037.
&&
$$
SYNOPSIS...DJN
NEAR TERM...DJN
SHORT TERM...DJN
LONG TERM...BJT
AVIATION...MDP
AREA FORECAST DISCUSSION
NWS BISMARCK ND
840 AM CST MON JAN 11 2016
.UPDATE...
ISSUED AT 840 AM CST MON JAN 11 2016
QUICK UPDATE TO INCREASE POPS TO THE CATEGORICAL /80-100 PERCENT/
RANGE OVER NORTH CENTRAL ND FROM MINOT TO ROLLA AND RUGBY THROUGH
LATE MORNING. RADAR IMAGERY AND SURFACE OBSERVATIONS SHOW THAT
LIGHT SNOW HAS QUICKLY INCREASED IN THAT AREA SINCE 1430 UTC.
OTHERWISE...NO SIGNIFICANT CHANGES TO THE REST OF THE FORECAST.
THE NEW 12 UTC NAM IS CONSISTENT WITH THE SNOW AND BLOWING SNOW
HAZARD THAT WILL DEVELOP ACROSS SOUTHWEST ND BY THIS AFTERNOON. NO
CHANGES NEEDED TO THE WINTER WEATHER ADVISORY AT THIS TIME.
UPDATE ISSUED AT 710 AM CST MON JAN 11 2016
GIVEN CONSISTENT TRENDS IN THE 08 THROUGH 11 UTC RAP AND HRRR
ITERATIONS...BUMPED UP THE START TIME FOR THE WINTER WEATHER
ADVISORY ACROSS THE FAR SOUTHWEST TO 17 UTC TO BETTER CAPTURE THE
ONSET OF SNOWFALL. THE RAP AND HRRR HAVE CONSISTENTLY HAD A
STRONGER WIND FIELD AND MORE SNOWFALL WHEN COMPARED TO THE GLOBAL
MODELS. AS OF LATE...THE RAP AND HRRR HAVE PERFORMED
WELL..ESPECIALLY REGARDING MESOSCALE SNOWFALL EVENTS. THE
CHALLENGE FOR TODAY IS IF THE ADVISORY FOR BLOWING SNOW MAY NEED
TO BE EXPANDED FURTHER EAST TO ALONG THE MISSOURI RIVER...WHERE
THE RAP AND HRRR SUGGEST AND INCH OR SO OF FRESH SNOW MAY BE
POSSIBLE.
UPDATE ISSUED AT 515 AM CST MON JAN 11 2016
WITH CONTINUED SUPPORT FROM THE HRRR/RAP13...AND NOW THE 4KM NAM
FOR WINDS OF 25KT TO 35KT IN THE MIXED LAYER ACROSS THE FAR
SOUTHWEST...WILL BE ISSUING A WINTER WEATHER ADVISORY FOR SNOW AND
BLOWING SNOW FROM 19Z MONDAY TO 02Z TUESDAY. STILL EXPECTING ONE
TO TWO INCHES WITH GUSTY WINDS COINCIDING WITH THE FALLING SNOW. THIS
INCLUDES GOLDEN VALLEY...BILLINGS...SLOPE...AND BOWMAN COUNTIES.
UPDATES FORTHCOMING.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 315 AM CST MON JAN 11 2016
HIGHLIGHTS IN THE SHORT TERM INCLUDE PATCHY BLOWING SNOW ALONG
WITH ISOLATED TO SCATTERED SNOW SHOWERS REDUCING VISIBILITIES
MONDAY AFTERNOON/EVENING. THE HIGHEST CONCERN IS THE FAR SOUTHWEST
WHERE 1 TO 2 INCHES OF SNOW THIS AFTERNOON COMBINED WITH GUSTY
WINDS PUTS THIS AREA AT GREATEST RISK FOR A POSSIBLE WINTER
WEATHER ADVISORY FOR BLOWING SNOW WITH VISIBILITIES AROUND ONE
HALF MILE. FOR NOW WE HAVE DECIDED TO MONITOR THE HRRR AND RAP13
BUFKIT SOUNDINGS TO SEE IF CURRENT TRENDS OF STRONGER WINDS
CONTINUE OVER THE NEXT SEVERAL HOURS. THAT ALLOWS SUFFICIENT TIME
IN THE NEXT ONE TO TWO UPDATE CYCLES TO ISSUE SOMETHING IF THE
SITUATION WARRANTS. OTHERWISE...WIND CHILL TEMPERATURES 25 TO 30
BELOW ZERO EXPECTED LATE MONDAY NIGHT NORTH CENTRAL AND INTO THE
NORTHERN JAMES RIVER VALLEY THROUGH TUESDAY MORNING. AFTER
COLLABORATING WITH NEIGHBORING OFFICES WILL AGAIN LET THE DAYSHIFT
HONE IN ON THE COUNTIES AFTER ANOTHER MODEL CYCLE COMES IN THIS
MORNING AND AFTERNOON.
THE LATEST WATER VAPOR IMAGERY SHOWS THIS NEXT SHORTWAVE THROUGH
NOW STREAMING THROUGH NORTHWEST SASKATCHEWAN AND DIVING SOUTHEAST
WITH TIME. ACCOMPANYING THE SHORTWAVE IS A 300MB 140KT JET STREAK.
WITH THE JET AND SHORTWAVE MAINTAINING A SOUTHEAST MOVEMENT THROUGH
00Z TUESDAY...THE FAVORED LEFT EXIT REGION OF THE JET FOR LARGE
SCALE ASCENT REMAINS JUST OFF TO OUR EAST. HENCE PRECIPITATION
AMOUNTS WILL REMAIN LIGHT AND THIS LIMITS SIGNIFICANT REDUCTIONS
IN VISIBILITIES. THE EXCEPTION WILL BE ACROSS THE HIGHER TERRAIN
IN THE FAR SOUTHWEST CLOSEST TO THE BAROCLINIC ZONE AND STRONGER
OMEGA/VERTICAL MOTION...FAVORING HIGHER AMOUNTS OF SNOWFALL.
ASSOCIATED WITH THE SHORTWAVE MENTIONED ABOVE IS AN ARCTIC FRONT
IN SOUTHERN ALBERTA/SASKATCHEWAN/MANITOBA...WHICH WILL SWEEP DOWN
ACROSS WESTERN AND CENTRAL NORTH DAKOTA TODAY. GUSTY NORTHWEST
WINDS BETWEEN 20 AND 35 MPH WILL DEVELOP IN ITS WAKE THIS AFTERNOON
AND INTO THE EARLY EVENING. THE STRONGEST WINDS FORECAST ACROSS
THE NORTH CENTRAL AND JAMES RIVER VALLEY WHICH FOLLOWS THE LOCATION
AND TRAJECTORY OF THE 6HR PRESSURE RISES AND UPPER JET MENTIONED
ABOVE. THE BAGGALEY BLOWING SNOW INDICATING THAT ONLY A VERY SMALL
AREA ACROSS THE NORTH CENTRAL WOULD BE IN LINE FOR A VERY LOW END
WINTER WEATHER ADVISORY FOR BLOWING SNOW...IF ONLY BLOWING SNOW
OCCURRED. ADDING A MENTION OF SNOWSHOWERS INTO THE FORMULA WITH A
WORST CASE SCENARIO OF AN INCH OF SNOW...A MORE WIDESPREAD LOW END
ADVISORY SHOWS UP. HOWEVER EXPECTATIONS ARE THAT SNOWFALL AMOUNTS
WILL REMAIN WELL UNDER ONE INCH...WITH THE EXCEPTION OF THE FAR
SOUTHWEST AS MENTIONED ABOVE. THUS WE HAVE DECIDED TO CONTINUE
WITH THE SPECIAL WEATHER STATEMENT ADVERTISING DRIFTING SNOW AND
PATCHY BLOWING SNOW REDUCING VISIBILITIES MAINLY IN OPEN COUNTRY.
MONDAY EVENING THE SURFACE WINDS WILL BEGIN DIMINISHING AS BOUNDARY
LAYER WINDS WEAKEN TO AROUND 20KT BY 06Z TUESDAY. SURFACE HIGH
PRESSURE MOVES FROM NEAR PLENTYWOOD MONTANA 06Z TUESDAY SOUTHEAST
INTO SOUTH CENTRAL SOUTH DAKOTA 12Z TUESDAY.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 315 AM CST MON JAN 11 2016
DANGEROUS WIND CHILLS TUESDAY MORNING...A POSSIBLE WARM UP INTO
THURSDAY...FOLLOWED BY ANOTHER POTENTIAL ARCTIC AIRMASS FOR FRIDAY
INTO THE WEEKEND HIGHLIGHT THE EXTENDED FORECAST.
DANGEROUS WIND CHILLS TO 30 BELOW ARE POSSIBLE ACROSS PORTIONS OF
CENTRAL NORTH DAKOTA TUESDAY MORNING IN ASSOCIATION WITH THE
ARCTIC AIRMASS ARRIVING MONDAY. THE WESTERN FRINGE OF THIS ARCTIC
AIRMASS IS FORECAST BY THE 00 UTC DETERMINISTIC AND ENSEMBLE
SUITES TO PROPAGATE EAST WEDNESDAY AND THURSDAY. THE RESULT IS A
POTENTIAL WARM UP WITH HIGHS WEDNESDAY AND THURSDAY IN THE UPPER
20S TO LOWER 30S ALONG AND WEST OF THE MISSOURI RIVER.
HOWEVER...AS HAS BEEN THE TREND OVER THE PAST COUPLE
DAYS...ANOTHER ARCTIC AIRMASS IS FORECAST TO POSSIBLY OVERTAKE THE
NORTHERN PLAINS FRIDAY INTO THE WEEKEND.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 710 AM CST MON JAN 11 2016
MVFR CIGS AT KISN/KDIK/KMOT WILL SPREAD SOUTHEAST TODAY WITH ALL
TERMINALS MVFR THROUGH AT LEAST 02Z TUESDAY. GUSTY NORTHWEST
WINDS TO 35KT MONDAY AFTERNOON IN CONJUNCTION WITH SNOW SHOWERS
WILL LEAD TO BLSN AND VSBYS IN THE MVFR/IFR RANGE BETWEEN 17Z
MONDAY AND 02Z TUESDAY. THE GREATEST IMPACTS ARE EXPECTED TO KDIK
WHERE SNOWFALL TODAY WILL BE GREATEST.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 7 PM MST THIS EVENING FOR NDZ031-
032-040-043.
&&
$$
UPDATE...CJS
SHORT TERM...KS
LONG TERM...AYD
AVIATION...AYD/KS/CJS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
719 AM CST MON JAN 11 2016
.UPDATE...
ISSUED AT 710 AM CST MON JAN 11 2016
GIVEN CONSISTENT TRENDS IN THE 08 THROUGH 11 UTC RAP AND HRRR
ITERATIONS...BUMPED UP THE START TIME FOR THE WINTER WEATHER
ADVISORY ACROSS THE FAR SOUTHWEST TO 17 UTC TO BETTER CAPTURE THE
ONSET OF SNOWFALL. THE RAP AND HRRR HAVE CONSISTENTLY HAD A
STRONGER WIND FIELD AND MORE SNOWFALL WHEN COMPARED TO THE GLOBAL
MODELS. AS OF LATE...THE RAP AND HRRR HAVE PERFORMED
WELL..ESPECIALLY REGARDING MESOSCALE SNOWFALL EVENTS. THE
CHALLENGE FOR TODAY IS IF THE ADVISORY FOR BLOWING SNOW MAY NEED
TO BE EXPANDED FURTHER EAST TO ALONG THE MISSOURI RIVER...WHERE
THE RAP AND HRRR SUGGEST AND INCH OR SO OF FRESH SNOW MAY BE
POSSIBLE.
UPDATE ISSUED AT 515 AM CST MON JAN 11 2016
WITH CONTINUED SUPPORT FROM THE HRRR/RAP13...AND NOW THE 4KM NAM
FOR WINDS OF 25KT TO 35KT IN THE MIXED LAYER ACROSS THE FAR
SOUTHWEST...WILL BE ISSUING A WINTER WEATHER ADVISORY FOR SNOW AND
BLOWING SNOW FROM 19Z MONDAY TO 02Z TUESDAY. STILL EXPECTING ONE
TO TWO INCHES WITH GUSTY WINDS COINCIDING WITH THE FALLING SNOW. THIS
INCLUDES GOLDEN VALLEY...BILLINGS...SLOPE...AND BOWMAN COUNTIES.
UPDATES FORTHCOMING.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 315 AM CST MON JAN 11 2016
HIGHLIGHTS IN THE SHORT TERM INCLUDE PATCHY BLOWING SNOW ALONG
WITH ISOLATED TO SCATTERED SNOW SHOWERS REDUCING VISIBILITIES
MONDAY AFTERNOON/EVENING. THE HIGHEST CONCERN IS THE FAR SOUTHWEST
WHERE 1 TO 2 INCHES OF SNOW THIS AFTERNOON COMBINED WITH GUSTY
WINDS PUTS THIS AREA AT GREATEST RISK FOR A POSSIBLE WINTER
WEATHER ADVISORY FOR BLOWING SNOW WITH VISIBILITIES AROUND ONE
HALF MILE. FOR NOW WE HAVE DECIDED TO MONITOR THE HRRR AND RAP13
BUFKIT SOUNDINGS TO SEE IF CURRENT TRENDS OF STRONGER WINDS
CONTINUE OVER THE NEXT SEVERAL HOURS. THAT ALLOWS SUFFICIENT TIME
IN THE NEXT ONE TO TWO UPDATE CYCLES TO ISSUE SOMETHING IF THE
SITUATION WARRANTS. OTHERWISE...WIND CHILL TEMPERATURES 25 TO 30
BELOW ZERO EXPECTED LATE MONDAY NIGHT NORTH CENTRAL AND INTO THE
NORTHERN JAMES RIVER VALLEY THROUGH TUESDAY MORNING. AFTER
COLLABORATING WITH NEIGHBORING OFFICES WILL AGAIN LET THE DAYSHIFT
HONE IN ON THE COUNTIES AFTER ANOTHER MODEL CYCLE COMES IN THIS
MORNING AND AFTERNOON.
THE LATEST WATER VAPOR IMAGERY SHOWS THIS NEXT SHORTWAVE THROUGH
NOW STREAMING THROUGH NORTHWEST SASKATCHEWAN AND DIVING SOUTHEAST
WITH TIME. ACCOMPANYING THE SHORTWAVE IS A 300MB 140KT JET STREAK.
WITH THE JET AND SHORTWAVE MAINTAINING A SOUTHEAST MOVEMENT THROUGH
00Z TUESDAY...THE FAVORED LEFT EXIT REGION OF THE JET FOR LARGE
SCALE ASCENT REMAINS JUST OFF TO OUR EAST. HENCE PRECIPITATION
AMOUNTS WILL REMAIN LIGHT AND THIS LIMITS SIGNIFICANT REDUCTIONS
IN VISIBILITIES. THE EXCEPTION WILL BE ACROSS THE HIGHER TERRAIN
IN THE FAR SOUTHWEST CLOSEST TO THE BAROCLINIC ZONE AND STRONGER
OMEGA/VERTICAL MOTION...FAVORING HIGHER AMOUNTS OF SNOWFALL.
ASSOCIATED WITH THE SHORTWAVE MENTIONED ABOVE IS AN ARCTIC FRONT
IN SOUTHERN ALBERTA/SASKATCHEWAN/MANITOBA...WHICH WILL SWEEP DOWN
ACROSS WESTERN AND CENTRAL NORTH DAKOTA TODAY. GUSTY NORTHWEST
WINDS BETWEEN 20 AND 35 MPH WILL DEVELOP IN ITS WAKE THIS AFTERNOON
AND INTO THE EARLY EVENING. THE STRONGEST WINDS FORECAST ACROSS
THE NORTH CENTRAL AND JAMES RIVER VALLEY WHICH FOLLOWS THE LOCATION
AND TRAJECTORY OF THE 6HR PRESSURE RISES AND UPPER JET MENTIONED
ABOVE. THE BAGGALEY BLOWING SNOW INDICATING THAT ONLY A VERY SMALL
AREA ACROSS THE NORTH CENTRAL WOULD BE IN LINE FOR A VERY LOW END
WINTER WEATHER ADVISORY FOR BLOWING SNOW...IF ONLY BLOWING SNOW
OCCURRED. ADDING A MENTION OF SNOWSHOWERS INTO THE FORMULA WITH A
WORST CASE SCENARIO OF AN INCH OF SNOW...A MORE WIDESPREAD LOW END
ADVISORY SHOWS UP. HOWEVER EXPECTATIONS ARE THAT SNOWFALL AMOUNTS
WILL REMAIN WELL UNDER ONE INCH...WITH THE EXCEPTION OF THE FAR
SOUTHWEST AS MENTIONED ABOVE. THUS WE HAVE DECIDED TO CONTINUE
WITH THE SPECIAL WEATHER STATEMENT ADVERTISING DRIFTING SNOW AND
PATCHY BLOWING SNOW REDUCING VISIBILITIES MAINLY IN OPEN COUNTRY.
MONDAY EVENING THE SURFACE WINDS WILL BEGIN DIMINISHING AS BOUNDARY
LAYER WINDS WEAKEN TO AROUND 20KT BY 06Z TUESDAY. SURFACE HIGH
PRESSURE MOVES FROM NEAR PLENTYWOOD MONTANA 06Z TUESDAY SOUTHEAST
INTO SOUTH CENTRAL SOUTH DAKOTA 12Z TUESDAY.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 315 AM CST MON JAN 11 2016
DANGEROUS WIND CHILLS TUESDAY MORNING...A POSSIBLE WARM UP INTO
THURSDAY...FOLLOWED BY ANOTHER POTENTIAL ARCTIC AIRMASS FOR FRIDAY
INTO THE WEEKEND HIGHLIGHT THE EXTENDED FORECAST.
DANGEROUS WIND CHILLS TO 30 BELOW ARE POSSIBLE ACROSS PORTIONS OF
CENTRAL NORTH DAKOTA TUESDAY MORNING IN ASSOCIATION WITH THE
ARCTIC AIRMASS ARRIVING MONDAY. THE WESTERN FRINGE OF THIS ARCTIC
AIRMASS IS FORECAST BY THE 00 UTC DETERMINISTIC AND ENSEMBLE
SUITES TO PROPAGATE EAST WEDNESDAY AND THURSDAY. THE RESULT IS A
POTENTIAL WARM UP WITH HIGHS WEDNESDAY AND THURSDAY IN THE UPPER
20S TO LOWER 30S ALONG AND WEST OF THE MISSOURI RIVER.
HOWEVER...AS HAS BEEN THE TREND OVER THE PAST COUPLE
DAYS...ANOTHER ARCTIC AIRMASS IS FORECAST TO POSSIBLY OVERTAKE THE
NORTHERN PLAINS FRIDAY INTO THE WEEKEND.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 710 AM CST MON JAN 11 2016
MVFR CIGS AT KISN/KDIK/KMOT WILL SPREAD SOUTHEAST TODAY WITH ALL
TERMINALS MVFR THROUGH AT LEAST 02Z TUESDAY. MVFR CIGS EXPECTED
AT KBIS/KJMS AFTER 17Z MONDAY. GUSTY NORTHWEST WINDS TO 35KT
MONDAY AFTERNOON IN CONJUNCTION WITH SNOW SHOWERS WILL LEAD TO
BLSN AND VSBYS IN THE MVFR/IFR RANGE BETWEEN 17Z MONDAY AND 02Z
TUESDAY. THE GREATEST IMPACTS ARE EXPECTED TO KDIK WHERE SNOWFALL
TODAY WILL BE GREATEST.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 10 AM THIS MORNING TO 7 PM MST THIS
EVENING FOR NDZ031-032-040-043.
&&
$$
UPDATE...AYD
SHORT TERM...KS
LONG TERM...AYD
AVIATION...AYD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
519 AM CST MON JAN 11 2016
.UPDATE...
ISSUED AT 515 AM CST MON JAN 11 2016
WITH CONTINUED SUPPORT FROM THE HRRR/RAP13...AND NOW THE 4KM NAM
FOR WINDS OF 25KT TO 35KT IN THE MIXED LAYER ACROSS THE FAR
SOUTHWEST...WILL BE ISSUING A WINTER WEATHER ADVISORY FOR SNOW AND
BLOWING SNOW FROM 19Z MONDAY TO 02Z TUESDAY. STILL EXPECTING ONE
TO TWO INCHES WITH GUSTY WINDS COINCIDING WITH THE FALLING SNOW. THIS
INCLUDES GOLDEN VALLEY...BILLINGS...SLOPE...AND BOWMAN COUNTIES.
UPDATES FORTHCOMING.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 315 AM CST MON JAN 11 2016
HIGHLIGHTS IN THE SHORT TERM INCLUDE PATCHY BLOWING SNOW ALONG
WITH ISOLATED TO SCATTERED SNOW SHOWERS REDUCING VISIBILITIES
MONDAY AFTERNOON/EVENING. THE HIGHEST CONCERN IS THE FAR SOUTHWEST
WHERE 1 TO 2 INCHES OF SNOW THIS AFTERNOON COMBINED WITH GUSTY
WINDS PUTS THIS AREA AT GREATEST RISK FOR A POSSIBLE WINTER
WEATHER ADVISORY FOR BLOWING SNOW WITH VISIBILITIES AROUND ONE
HALF MILE. FOR NOW WE HAVE DECIDED TO MONITOR THE HRRR AND RAP13
BUFKIT SOUNDINGS TO SEE IF CURRENT TRENDS OF STRONGER WINDS
CONTINUE OVER THE NEXT SEVERAL HOURS. THAT ALLOWS SUFFICIENT TIME
IN THE NEXT ONE TO TWO UPDATE CYCLES TO ISSUE SOMETHING IF THE
SITUATION WARRANTS. OTHERWISE...WIND CHILL TEMPERATURES 25 TO 30
BELOW ZERO EXPECTED LATE MONDAY NIGHT NORTH CENTRAL AND INTO THE
NORTHERN JAMES RIVER VALLEY THROUGH TUESDAY MORNING. AFTER
COLLABORATING WITH NEIGHBORING OFFICES WILL AGAIN LET THE DAYSHIFT
HONE IN ON THE COUNTIES AFTER ANOTHER MODEL CYCLE COMES IN THIS
MORNING AND AFTERNOON.
THE LATEST WATER VAPOR IMAGERY SHOWS THIS NEXT SHORTWAVE THROUGH
NOW STREAMING THROUGH NORTHWEST SASKATCHEWAN AND DIVING SOUTHEAST
WITH TIME. ACCOMPANYING THE SHORTWAVE IS A 300MB 140KT JET STREAK.
WITH THE JET AND SHORTWAVE MAINTAINING A SOUTHEAST MOVEMENT THROUGH
00Z TUESDAY...THE FAVORED LEFT EXIT REGION OF THE JET FOR LARGE
SCALE ASCENT REMAINS JUST OFF TO OUR EAST. HENCE PRECIPITATION
AMOUNTS WILL REMAIN LIGHT AND THIS LIMITS SIGNIFICANT REDUCTIONS
IN VISIBILITIES. THE EXCEPTION WILL BE ACROSS THE HIGHER TERRAIN
IN THE FAR SOUTHWEST CLOSEST TO THE BAROCLINIC ZONE AND STRONGER
OMEGA/VERTICAL MOTION...FAVORING HIGHER AMOUNTS OF SNOWFALL.
ASSOCIATED WITH THE SHORTWAVE MENTIONED ABOVE IS AN ARCTIC FRONT
IN SOUTHERN ALBERTA/SASKATCHEWAN/MANITOBA...WHICH WILL SWEEP DOWN
ACROSS WESTERN AND CENTRAL NORTH DAKOTA TODAY. GUSTY NORTHWEST
WINDS BETWEEN 20 AND 35 MPH WILL DEVELOP IN ITS WAKE THIS AFTERNOON
AND INTO THE EARLY EVENING. THE STRONGEST WINDS FORECAST ACROSS
THE NORTH CENTRAL AND JAMES RIVER VALLEY WHICH FOLLOWS THE LOCATION
AND TRAJECTORY OF THE 6HR PRESSURE RISES AND UPPER JET MENTIONED
ABOVE. THE BAGGALEY BLOWING SNOW INDICATING THAT ONLY A VERY SMALL
AREA ACROSS THE NORTH CENTRAL WOULD BE IN LINE FOR A VERY LOW END
WINTER WEATHER ADVISORY FOR BLOWING SNOW...IF ONLY BLOWING SNOW
OCCURRED. ADDING A MENTION OF SNOWSHOWERS INTO THE FORMULA WITH A
WORST CASE SCENARIO OF AN INCH OF SNOW...A MORE WIDESPREAD LOW END
ADVISORY SHOWS UP. HOWEVER EXPECTATIONS ARE THAT SNOWFALL AMOUNTS
WILL REMAIN WELL UNDER ONE INCH...WITH THE EXCEPTION OF THE FAR
SOUTHWEST AS MENTIONED ABOVE. THUS WE HAVE DECIDED TO CONTINUE
WITH THE SPECIAL WEATHER STATEMENT ADVERTISING DRIFTING SNOW AND
PATCHY BLOWING SNOW REDUCING VISIBILITIES MAINLY IN OPEN COUNTRY.
MONDAY EVENING THE SURFACE WINDS WILL BEGIN DIMINISHING AS BOUNDARY
LAYER WINDS WEAKEN TO AROUND 20KT BY 06Z TUESDAY. SURFACE HIGH
PRESSURE MOVES FROM NEAR PLENTYWOOD MONTANA 06Z TUESDAY SOUTHEAST
INTO SOUTH CENTRAL SOUTH DAKOTA 12Z TUESDAY.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 315 AM CST MON JAN 11 2016
DANGEROUS WIND CHILLS TUESDAY MORNING...A POSSIBLE WARM UP INTO
THURSDAY...FOLLOWED BY ANOTHER POTENTIAL ARCTIC AIRMASS FOR FRIDAY
INTO THE WEEKEND HIGHLIGHT THE EXTENDED FORECAST.
DANGEROUS WIND CHILLS TO 30 BELOW ARE POSSIBLE ACROSS PORTIONS OF
CENTRAL NORTH DAKOTA TUESDAY MORNING IN ASSOCIATION WITH THE
ARCTIC AIRMASS ARRIVING MONDAY. THE WESTERN FRINGE OF THIS ARCTIC
AIRMASS IS FORECAST BY THE 00 UTC DETERMINISTIC AND ENSEMBLE
SUITES TO PROPAGATE EAST WEDNESDAY AND THURSDAY. THE RESULT IS A
POTENTIAL WARM UP WITH HIGHS WEDNESDAY AND THURSDAY IN THE UPPER
20S TO LOWER 30S ALONG AND WEST OF THE MISSOURI RIVER.
HOWEVER...AS HAS BEEN THE TREND OVER THE PAST COUPLE
DAYS...ANOTHER ARCTIC AIRMASS IS FORECAST TO POSSIBLY OVERTAKE THE
NORTHERN PLAINS FRIDAY INTO THE WEEKEND.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY) ISSUED AT 315 AM
CST MON JAN 11 2016
MVFR CIGS AT KISN/KDIK/KMOT WILL SPREAD SOUTHEAST TODAY WITH ALL
TERMINALS MVFR THROUGH AT LEAST 02Z TUESDAY. MVFR CIGS EXPECTED
AT KBIS/KJMS AFTER 17Z MONDAY. GUSTY NORTHWEST WINDS TO 30KT
MONDAY AFTERNOON IN CONJUNCTION WITH ISOLATED SNOW SHOWERS
WILL LEAD TO -SN/BLSN AND VSBYS IN THE MVFR RANGE BETWEEN 18Z
MONDAY AND 02Z TUESDAY. WINDS WILL DIMINISH AFTER 00Z TUESDAY
WITH CIGS SLOWLY IMPROVING TO LOW VFR THROUGH 12Z TUESDAY.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM NOON TODAY TO 7 PM MST THIS EVENING
FOR NDZ031-032-040-043.
&&
$$
UPDATE...KS
SHORT TERM...KS
LONG TERM...AYD
AVIATION...KS
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
751 AM EST MON JAN 11 2016
.SYNOPSIS...
A DEEP UPPER LEVEL TROUGH WILL PIVOT THROUGH THE NORTHEAST CONUS
EARLY THIS WEEK...WITH AN ALBERTA CLIPPER TRACKING NORTH OF THE
COMMONWEALTH ON TUESDAY. THE UPPER TROUGH WILL LIFT OUT OF THE
REGION BY THE END OF THE WEEK WITH ANOTHER LOW LIKELY TRACKING
WEST OF PA LATE FRIDAY OR EARLY SATURDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
BACKING FLOW IN THE BLYR CAUSING LAKE EFFECT SNOW SHOWERS TO SHIFT
NORTH OF THE BORDER EARLY THIS AM. EARLIER MULTIBAND SNOW SHOWERS
HAVE TRANSITIONED TO A MORE IMPRESSIVE SINGLE BAND AFFECTING
WESTERN NY STATE. STILL ENOUGH MOISTURE TO SQUEEZE OUT SOME LIGHT
OROGRAPHIC SNOW SHOWERS ACROSS THE NW MTNS THIS MORNING. RADAR
TRENDS AND LATEST HRRR SUGGEST NO MORE THAN AN ADDITIONAL DUSTING
ACROSS PORTIONS OF NW WARREN CO TODAY. FURTHER SOUTH...HAVE
REMOVED ANY MENTION OF MEASURABLE SNOW ACROSS THE CENTRAL
MTNS/LAURELS...WHERE INVERSION HGTS ARE ON THE RISE AHEAD OF
APPROACHING SFC RIDGE OVR THE OHIO VALLEY.
IR SATL LOOP ALREADY SHOWING MCLEAR SKIES ACROSS THE LOWER SUSQ
VALLEY AT 10Z AND EXPECT THIS CLEARING TREND TO WORK NORTHWARD
TODAY AS RIDGE OF HIGH PRES BUILD IN FROM THE OHIO VALLEY. ENS
MEAN 8H TEMPS OF JUST -16C SHOULD TRANSLATE TO MAX TEMPS FROM THE
UTEENS ACROSS THE NW MTNS...TO THE L30S OVR THE LOWER SUSQ VALLEY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
FAIR WX AND DIMINISHING WIND EXPECTED THIS EVENING...AS SFC RIDGE
AXIS PASSES OVR PA. CLOUDS SHOULD OVERSPREAD THE STATE FROM THE
WEST LATE TONIGHT IN REGION OF WAA AHEAD OF CLIPPER WORKING ACROSS
THE GRT LKS. THIS SCENARIO WILL LIKELY RESULT IN MIN TEMPS DURING
THE EVENING...ESP ACROSS THE NW MTNS...WHERE CLOUDS WILL ARRIVE
FIRST.
ALL MDL DATA TRACKS ALBERTA CLIPPER AND BULK OF IT/S PRECIP NORTH
OF PA TUESDAY. HOWEVER...WAA ALONG ASSOC SWRLY LL JET WILL PRODUCE
A PERIOD OF LIGHT SNOW EARLY TUESDAY AM ACROSS PRIMARILY THE NW
MTNS...WHERE OROGRAPHIC FORCING WILL PLAY A SIG ROLE. NCAR MESO
ENSEMBLE SUPPORTS A GENERAL 1-2 INCH SNOWFALL ACROSS THE NW MTNS
EARLY TUESDAY. SOME MUCH LIGHTER SNOW/FLURRIES IS LIKELY TO
ACCOMPANY PASSAGE OF LL JET ACROSS AREAS EAST OF THE MTNS.
THE BIGGER CONCERN WILL COME WITH PASSAGE OF SHARP COLD FRONT
TUES PM. STEEP LOWER TROPOSPHERIC LAPSE RTS AND EVEN SOME MARGINAL
MDL CAPES INDICATED WITH FROPA...INDICATING THE POTENTIAL OF BRIEF
GROUND WHITENING SNOW SQUALLS. THE BRIEFLY LOWERED
VSBYS...COMBINED WITH POTENTIAL FLASH FREEZE AS TEMPS FALL BLW
32F...COULD CREATE A TRAVEL HAZARD TUES AFTN/EVE. WILL CONTINUE TO
HIGHLIGHT THIS THREAT IN THE HWO.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
BLUSTERY/COLD CONDS WILL OVERSPREAD THE REGION IN WAKE OF CLIPPER
TUE NIGHT/WED. OTHER THAN THE COLD...BIGGEST CONCERN WILL BE LAKE
EFFECT SNOW ACROSS THE NW MTNS. SEVERAL INCHES OF ACCUM APPEAR
LIKELY ATTM ACROSS THE SNOWBELT OF WARREN CO. WILL MENTION THREAT
IN HWO.
ALL GUIDANCE INDICATING MODERATING TEMPS LATE WEEK...AS UPPER TROF
LIFTS OUT. BULK OF MED RANGE MDLS INCLUDING 00Z GEFS/ECENS TRACK
LATE WEEK SFC LOW WEST OF PA. HAVE INCREASED POPS AND RAISED TEMPS FRI
NIGHT/SAT ACCORDINGLY AND AM NOW FAVORING RAIN RATHER THAN SNOW.
ECENS/GEFS BOTH INDICATING DRY/COLD WX ARRIVING LATE IN THE
WEEKEND...AS DEEP UPPER TROF AXIS SWINGS THRU THE NE CONUS.
&&
.AVIATION /13Z MONDAY THROUGH FRIDAY/...
TROUGH LIFTING NORTHWARD EARLY THIS MORNING HAS TAKEN SNOW BANDS
OVER THE NW MTNS ALONG WITH IT. VFR IN PLACE AT CENTRAL AND
EASTERN TERMINALS ALREADY...AND AS FLOW TURNS A BIT MORE SW
TODAY IMPROVEMENTS WILL COME TO WESTERN HIGHER TERRAIN EVENTUALLY
AS WELL AS KJST IMPROVES TO VFR LATER THIS MORNING WITH KBFD
JOINING IN THE AFTERNOON. WINDS WILL REMAIN GUSTY MUCH OF THE
DAY...BEFORE DIMINISHING LATE.
VFR THIS EVENING AS HIGH PRESSURE SLIDES EAST...BUT WAA ON SW LL
JET AHEAD OF AN APPROACHING CLIPPER OVERNIGHT WILL BRING
REDUCTIONS BACK INTO WESTERN HIGH TERRAIN WITH LIGHT SNOW
DEVELOPING. THE LIGHT SNOW WILL EDGE EASTWARD THROUGH MIDDAY WITH
MVFR REDUCTIONS LIKELY. SHARP COLD FRONT SWEEPS THROUGH TUE
AFTERNOON WITH POTENTIAL FOR BRIEF SNOW SQUALLS AS WINDS AGAIN
BECOME STRONG FROM THE WEST.
OUTLOOK...
TUE...CIG REDUCTIONS LIKELY NW HALF INTO PORTIONS OF CENTRAL MTNS IN
LIGHT SNOW. VFR SE.
WED-THU...CIG REDUCTIONS LIKELY NW HALF IN SNOW SHOWERS. VFR
ELSEWHERE.
FRI...NO SIG WX.
SAT...REDUCTIONS POSS WITH CHANCE FOR RAIN/SNOW.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...FITZGERALD
NEAR TERM...FITZGERALD
SHORT TERM...FITZGERALD
LONG TERM...FITZGERALD
AVIATION...RXR
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
621 AM EST MON JAN 11 2016
.SYNOPSIS...
A DEEP UPPER LEVEL TROUGH WILL PIVOT THROUGH THE NORTHEAST CONUS
EARLY THIS WEEK...WITH AN ALBERTA CLIPPER TRACKING NORTH OF THE
COMMONWEALTH ON TUESDAY. THE UPPER TROUGH WILL LIFT OUT OF THE
REGION BY THE END OF THE WEEK WITH ANOTHER LOW LIKELY TRACKING
WEST OF PA LATE FRIDAY OR EARLY SATURDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
BACKING FLOW IN THE BLYR CAUSING LAKE EFFECT SNOW SHOWERS TO SHIFT
NORTH OF THE BORDER EARLY THIS AM. EARLIER MULTIBAND SNOW SHOWERS
HAVE TRANSITIONED TO A MORE IMPRESSIVE SINGLE BAND AFFECTING
WESTERN NY STATE. STILL ENOUGH MOISTURE TO SQUEEZE OUT SOME LIGHT
OROGRAPHIC SNOW SHOWERS ACROSS THE NW MTNS THIS MORNING. RADAR
TRENDS AND LATEST HRRR SUGGEST NO MORE THAN AN ADDITIONAL DUSTING
ACROSS PORTIONS OF NW WARREN CO TODAY. FURTHER SOUTH...HAVE
REMOVED ANY MENTION OF MEASURABLE SNOW ACROSS THE CENTRAL
MTNS/LAURELS...WHERE INVERSION HGTS ARE ON THE RISE AHEAD OF
APPROACHING SFC RIDGE OVR THE OHIO VALLEY.
IR SATL LOOP ALREADY SHOWING MCLEAR SKIES ACROSS THE LOWER SUSQ
VALLEY AT 10Z AND EXPECT THIS CLEARING TREND TO WORK NORTHWARD
TODAY AS RIDGE OF HIGH PRES BUILD IN FROM THE OHIO VALLEY. ENS
MEAN 8H TEMPS OF JUST -16C SHOULD TRANSLATE TO MAX TEMPS FROM THE
UTEENS ACROSS THE NW MTNS...TO THE L30S OVR THE LOWER SUSQ VALLEY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
FAIR WX AND DIMINISHING WIND EXPECTED THIS EVENING...AS SFC RIDGE
AXIS PASSES OVR PA. CLOUDS SHOULD OVERSPREAD THE STATE FROM THE
WEST LATE TONIGHT IN REGION OF WAA AHEAD OF CLIPPER WORKING ACROSS
THE GRT LKS. THIS SCENARIO WILL LIKELY RESULT IN MIN TEMPS DURING
THE EVENING...ESP ACROSS THE NW MTNS...WHERE CLOUDS WILL ARRIVE
FIRST.
ALL MDL DATA TRACKS ALBERTA CLIPPER AND BULK OF IT/S PRECIP NORTH
OF PA TUESDAY. HOWEVER...WAA ALONG ASSOC SWRLY LL JET WILL PRODUCE
A PERIOD OF LIGHT SNOW EARLY TUESDAY AM ACROSS PRIMARILY THE NW
MTNS...WHERE OROGRAPHIC FORCING WILL PLAY A SIG ROLE. NCAR MESO
ENSEMBLE SUPPORTS A GENERAL 1-2 INCH SNOWFALL ACROSS THE NW MTNS
EARLY TUESDAY. SOME MUCH LIGHTER SNOW/FLURRIES IS LIKELY TO
ACCOMPANY PASSAGE OF LL JET ACROSS AREAS EAST OF THE MTNS.
THE BIGGER CONCERN WILL COME WITH PASSAGE OF SHARP COLD FRONT
TUES PM. STEEP LOWER TROPOSPHERIC LAPSE RTS AND EVEN SOME MARGINAL
MDL CAPES INDICATED WITH FROPA...INDICATING THE POTENTIAL OF BRIEF
GROUND WHITENING SNOW SQUALLS. THE BRIEFLY LOWERED
VSBYS...COMBINED WITH POTENTIAL FLASH FREEZE AS TEMPS FALL BLW
32F...COULD CREATE A TRAVEL HAZARD TUES AFTN/EVE. WILL CONTINUE TO
HIGHLIGHT THIS THREAT IN THE HWO.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
BLUSTERY/COLD CONDS WILL OVERSPREAD THE REGION IN WAKE OF CLIPPER
TUE NIGHT/WED. OTHER THAN THE COLD...BIGGEST CONCERN WILL BE LAKE
EFFECT SNOW ACROSS THE NW MTNS. SEVERAL INCHES OF ACCUM APPEAR
LIKELY ATTM ACROSS THE SNOWBELT OF WARREN CO. WILL MENTION THREAT
IN HWO.
ALL GUIDANCE INDICATING MODERATING TEMPS LATE WEEK...AS UPPER TROF
LIFTS OUT. BULK OF MED RANGE MDLS INCLUDING 00Z GEFS/ECENS TRACK
LATE WEEK SFC LOW WEST OF PA. HAVE INCREASED POPS AND RAISED TEMPS FRI
NIGHT/SAT ACCORDINGLY AND AM NOW FAVORING RAIN RATHER THAN SNOW.
ECENS/GEFS BOTH INDICATING DRY/COLD WX ARRIVING LATE IN THE
WEEKEND...AS DEEP UPPER TROF AXIS SWINGS THRU THE NE CONUS.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
BANDS OF PRECIPITATION CONTINUE ACROSS THE CENTRAL MOUNTAINS AND
THROUGH THE NORTHERN HALF OF CENTRAL PA CURRENTLY AND THROUGH 09Z.
EXPECT THAT AS THE TROUGH MOVES TO THE NORTH THE BAND OF
PRECIPITATION WILL MOVE NORTHWARD...WITH THE IFR INDUCING
CONDITIONS ENDING BETWEEN 07Z TO 09Z AS THE LATEST HRRR CONTINUES
TO SHOW THE PRECIPITATION BANDS WILL FADE AS THE TROUGH MOVES TO
THE NORTHEAST. EXPECT THAT SNOW BANDS WILL DISSIPATE AFTER 09Z.
OVERALL MVFR CONDITIONS WILL CONTINUE OVERNIGHT AT BFD...WITH IFR
VSBYS AT TIMES IN THE HEAVIER BANDS OF PRECIPITATION.
DOWNSLOPE FLOW HAS BROUGHT CIG IMPROVEMENTS TO VFR OVER THE
EAST...WHILE UPSLOPE AND PROXIMITY TO UPPER LOW WILL KEEP CIG
RESTRICTIONS IN PLACE OVER THE WEST.
CIG RESTRICTIONS SHOULD LIFT BY EARLY MORNING WITH MAINLY VFR
TOMORROW.
OUTLOOK...
MON...A FEW LOCALIZED BANDS OF LOW CIGS AND VSBYS IN SNOW SHOWERS
ACROSS THE LAUREL HIGHLANDS AND NW MTNS POSSIBLE.
OTHERWISE...QUITE BREEZY WITH NO WIDESPREAD SIG WX RESTRICTIONS
EXPECTED.
TUE...CIG REDUCTIONS LIKELY NW HALF INTO PORTIONS OF CENTRAL MTNS IN
LIGHT SNOW. VFR SE.
WED-THU...CIG REDUCTIONS LIKELY NW HALF IN SNOW SHOWERS. VFR
ELSEWHERE.
FRI...FAIR.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...FITZGERALD
NEAR TERM...FITZGERALD
SHORT TERM...FITZGERALD
LONG TERM...FITZGERALD
AVIATION...DEVOIR/CERU
AREA FORECAST DISCUSSION...UPDATED
NWS AUSTIN/SAN ANTONIO TX
834 AM CST MON JAN 11 2016
.UPDATE...
WE HAVE UPDATED THE FORECAST TO REMOVE THE WORDING FOR THE NOW
EXPIRED FREEZE WARNING. OTHERWISE...MINOR CHANGES HAVE BEEN MADE
TO THE HOURLY TEMPERATURES...DEW POINTS AND WINDS TO ACCOUNT FOR
RECENT OBSERVATIONS.
&&
.PREV DISCUSSION... /ISSUED 542 AM CST MON JAN 11 2016/
AVIATION.../12Z TAFS/
AN UPPER LEVEL DISTURBANCE WILL PASS OVER TX LATE
TODAY...INCREASING MID TO HIGH LEVEL CLOUDS AHEAD OF IT. A LAYER
OF MID CLOUDS IS LIFTING NORTH FROM DEEP SOUTH TX AND SHOULD BE ON
PACE TO REACH SSF/SAT BY LATE MORNING. LOWER LEVELS ARE EXPECTED
TO REMAIN DRY WITH LIGHT EASTERLY WINDS...SO NO MVFR CIGS OR VSBYS
ARE EXPECTED TO DEVELOP THROUGH TONIGHT.
PREV DISCUSSION... /ISSUED 310 AM CST MON JAN 11 2016/
SHORT TERM (TODAY THROUGH TUESDAY)...
MAIN HEADLINE IN THE SHORT TERM WILL BE THE ISOLATED POCKETS OF
FREEZING TEMPERATURES ACROSS THE HIGHER ELEVATIONS OF BEXAR AND INTO
PORTIONS OF COASTAL PLAINS WHERE LESS CLOUDS RESIDE. OUTSIDE OF THIS
MARGINAL HAZARD - EXPECT VERY LOW END RAIN CHANCES FOR THE FAR
SOUTHEAST COASTAL PLAINS THIS EVENING INTO EARLY TUESDAY MORNING.
MOST LOCATIONS WILL NOT SEE ANY RAIN WITH PARTLY TO MOSTLY CLOUDY
SKIES TODAY.
SYNOPTIC PATTERN VIA WATER VAPOR CHANNELS AND RAP ANALYSIS DEPICTS
SPLIT FLOW BEGINNING TO DEVELOP AS THE SOUTHERN JET-STREAM BRANCH
BECOMES MORE ACTIVE. A HIGHLY POSITIVELY-TILTED SHORTWAVE TROUGH IS
OVER NEW MEXICO AND THIS, ALONG WITH WEAK MID-LEVEL DIVERGENCE, IS
ALLOWING FOR ELEVATED ECHOS TO APPEAR ON RADAR. THIS PRECIPITATION
IS NOT REACHING THE GROUND BUT THE RESULTANT CLOUDS ARE KEEPING
TEMPERATURES FROM BOTTOMING TO THEIR FULL POTENTIAL. BOERNE IS
CURRENTLY JUST BELOW THE FREEZING MARK AND COASTAL PLAIN
LOCATIONS WITHIN THE FREEZE WARNING ARE UNDER CLEAR SKIES AND
HEADING THAT DIRECTION. THE FREEZE WARNING IS IN EFFECT FROM 4AM
THROUGH 8AM AND TEMPERATURES ARE NOT EXPECTED TO BE AT FREEZING
FOR VERY LONG.
HAVE DELAYED THE ONSET OF ANY LIGHT RAIN/DRIZZLE UNTIL THIS EVENING
ACROSS THE FAR SOUTHEAST COASTAL PLAINS. OVERALL AVAILABLE MOISTURE
APPEARS TO BE MORE MEAGER THAN EVEN THE ALREADY LOW VALUES
ADVERTISED YESTERDAY. A WEAK BOUNDARY/PACIFIC FRONT WILL PUSH
THROUGH TUESDAY MORNING BRINING DRIER AIR IN THE SFC-700MB LAYER.
AMPLE SUN IS EXPECTED TUESDAY AFTERNOON AND A NICE WARM UP IS
EXPECTED INTO THE LOW 60S.
LONG TERM (WEDNESDAY THROUGH NEXT SUNDAY)...
DESPITE AN ACTIVE SOUTHERN JET-STREAM BRANCH AND SEVERAL PACIFIC
FRONTS EXPECTED TO MOVE THROUGH THE REGION THIS PERIOD...OVERALL
RAIN AMOUNTS REMAIN LOW. NO SIGNIFICANT HAZARDS APPEAR TO BE ON TAP
AT THIS POINT GIVEN THE MIS-ALIGNING OF LIMITED MOISTURE POOLING AND
DEEPER FORCING MECHANISMS. A GRADUAL WARM UP IS ANTICIPATED INTO THE
MID AND EVEN UPPER 60S BY THE END OF THE WEEK.
GLOBAL MODELS REMAIN AT ODDS WITH EACH OTHER CONCERNING THE
DIFFICULT PROGNOSTICATION OF THE SPLIT JET-STREAM FLOW. HAVE
FOLLOWED MORE OF A 33/33/33 WEIGHTED FORECAST WITH THE GFS/EC/GEM
THIS PACKAGE AS THE EC/GEM TEND TO HAVE MORE SUPPORT FROM THE NAM
AND UKMET MODELS IN MEDIUM AND LONG RANGE.
BY MID WEEK...ENERGY FROM THE CURRENT SHORTWAVE TROUGH WILL GET
TRAPPED/CUT-OFF OVER MEXICO AND IT WILL BE THIS COMPLEX THAT WILL
GIVE LIFT TO THE LIMITED MOISTURE IN PLACE LATE WEDNESDAY INTO
THURSDAY. GFS IS QUICKER AS IT PHASES SOME NORTHERN STREAM ENERGY IN
BUT EC/GEM/NAM ARE SLOWER. HAVE LEANED SLOWER AND PLACED 20-40% RAIN
CHANCES FROM WEST TO EAST FROM THE 35 CORRIDOR TO THE COASTAL
PLAINS. BEST TIME-FRAME FOR RAIN WILL BEGIN LATE WEDNESDAY NIGHT
THROUGH THURSDAY AFTERNOON. WESTERN AREAS STILL APPEAR TOO DRY FOR
ANY ACCUMULATING RAINFALL. A PACIFIC FRONT WILL PUSH THROUGH THE
REGION BY EARLY FRIDAY AND END RAIN CHANCES AS THE AFOREMENTIONED CUT-
OFF ENERGY PHASES WITH A STRONGER PASSING NORTHERN STREAM TROUGH.
WITH THE BRISK H5 FLOW, THE NEXT TROUGH APPROACHES THE REGION BY
SATURDAY. PWATS WILL BE 0.3-0.4" AND IT WILL BE DIFFICULT TO HAVE
PRECIPITATION REACH THE GROUND. HAVE OPTED FOR A DRY FORECAST FOR
NOW BUT CLOUDS WILL CERTAINLY BE ON THE INCREASE SATURDAY. BY
SUNDAY...THE TROUGH WILL SHIFT EAST AND USHER IN A POSSIBLE HYBRID
PACIFIC/BACKDOOR FRONT FROM THE NORTH. THIS SHOULD KEEP US DRY
SUNDAY BUT YET ANOTHER SYSTEM WILL BE ON ITS HEELS THAT APPEARS
STRONGER AND A BETTER CHANCE OF RAIN APPEARS POSSIBLE NEXT TUESDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 53 37 63 40 62 / 10 - 0 0 10
AUSTIN BERGSTROM INTL AIRPORT 53 34 62 36 61 / 10 - 0 0 10
NEW BRAUNFELS MUNI AIRPORT 54 35 63 39 61 / 10 - 0 - 10
BURNET MUNI AIRPORT 51 34 61 37 60 / 10 0 0 0 -
DEL RIO INTL AIRPORT 55 36 62 40 61 / - 0 0 0 0
GEORGETOWN MUNI AIRPORT 52 34 61 37 60 / 10 - 0 0 10
HONDO MUNI AIRPORT 54 34 62 39 60 / 10 - 0 - 10
SAN MARCOS MUNI AIRPORT 54 36 62 38 60 / 10 - 0 - 10
LA GRANGE - FAYETTE REGIONAL 55 38 62 40 62 / 10 10 0 - 10
SAN ANTONIO INTL AIRPORT 54 37 63 40 61 / 10 - 0 - 10
STINSON MUNI AIRPORT 55 38 63 41 61 / 10 - 0 - 10
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...05
SYNOPTIC/GRIDS...24
PUBLIC SERVICE/DATA COLLECTION...33
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
542 AM CST MON JAN 11 2016
.AVIATION.../12Z TAFS/
AN UPPER LEVEL DISTURBANCE WILL PASS OVER TX LATE
TODAY...INCREASING MID TO HIGH LEVEL CLOUDS AHEAD OF IT. A LAYER
OF MID CLOUDS IS LIFTING NORTH FROM DEEP SOUTH TX AND SHOULD BE ON
PACE TO REACH SSF/SAT BY LATE MORNING. LOWER LEVELS ARE EXPECTED
TO REMAIN DRY WITH LIGHT EASTERLY WINDS...SO NO MVFR CIGS OR VSBYS
ARE EXPECTED TO DEVELOP THROUGH TONIGHT.
&&
.PREV DISCUSSION... /ISSUED 310 AM CST MON JAN 11 2016/
SHORT TERM (TODAY THROUGH TUESDAY)...
MAIN HEADLINE IN THE SHORT TERM WILL BE THE ISOLATED POCKETS OF
FREEZING TEMPERATURES ACROSS THE HIGHER ELEVATIONS OF BEXAR AND INTO
PORTIONS OF COASTAL PLAINS WHERE LESS CLOUDS RESIDE. OUTSIDE OF THIS
MARGINAL HAZARD - EXPECT VERY LOW END RAIN CHANCES FOR THE FAR
SOUTHEAST COASTAL PLAINS THIS EVENING INTO EARLY TUESDAY MORNING.
MOST LOCATIONS WILL NOT SEE ANY RAIN WITH PARTLY TO MOSTLY CLOUDY
SKIES TODAY.
SYNOPTIC PATTERN VIA WATER VAPOR CHANNELS AND RAP ANALYSIS DEPICTS
SPLIT FLOW BEGINNING TO DEVELOP AS THE SOUTHERN JET-STREAM BRANCH
BECOMES MORE ACTIVE. A HIGHLY POSITIVELY-TILTED SHORTWAVE TROUGH IS
OVER NEW MEXICO AND THIS, ALONG WITH WEAK MID-LEVEL DIVERGENCE, IS
ALLOWING FOR ELEVATED ECHOS TO APPEAR ON RADAR. THIS PRECIPITATION
IS NOT REACHING THE GROUND BUT THE RESULTANT CLOUDS ARE KEEPING
TEMPERATURES FROM BOTTOMING TO THEIR FULL POTENTIAL. BOERNE IS
CURRENTLY JUST BELOW THE FREEZING MARK AND COASTAL PLAIN
LOCATIONS WITHIN THE FREEZE WARNING ARE UNDER CLEAR SKIES AND
HEADING THAT DIRECTION. THE FREEZE WARNING IS IN EFFECT FROM 4AM
THROUGH 8AM AND TEMPERATURES ARE NOT EXPECTED TO BE AT FREEZING
FOR VERY LONG.
HAVE DELAYED THE ONSET OF ANY LIGHT RAIN/DRIZZLE UNTIL THIS EVENING
ACROSS THE FAR SOUTHEAST COASTAL PLAINS. OVERALL AVAILABLE MOISTURE
APPEARS TO BE MORE MEAGER THAN EVEN THE ALREADY LOW VALUES
ADVERTISED YESTERDAY. A WEAK BOUNDARY/PACIFIC FRONT WILL PUSH
THROUGH TUESDAY MORNING BRINING DRIER AIR IN THE SFC-700MB LAYER.
AMPLE SUN IS EXPECTED TUESDAY AFTERNOON AND A NICE WARM UP IS
EXPECTED INTO THE LOW 60S.
LONG TERM (WEDNESDAY THROUGH NEXT SUNDAY)...
DESPITE AN ACTIVE SOUTHERN JET-STREAM BRANCH AND SEVERAL PACIFIC
FRONTS EXPECTED TO MOVE THROUGH THE REGION THIS PERIOD...OVERALL
RAIN AMOUNTS REMAIN LOW. NO SIGNIFICANT HAZARDS APPEAR TO BE ON TAP
AT THIS POINT GIVEN THE MIS-ALIGNING OF LIMITED MOISTURE POOLING AND
DEEPER FORCING MECHANISMS. A GRADUAL WARM UP IS ANTICIPATED INTO THE
MID AND EVEN UPPER 60S BY THE END OF THE WEEK.
GLOBAL MODELS REMAIN AT ODDS WITH EACH OTHER CONCERNING THE
DIFFICULT PROGNOSTICATION OF THE SPLIT JET-STREAM FLOW. HAVE
FOLLOWED MORE OF A 33/33/33 WEIGHTED FORECAST WITH THE GFS/EC/GEM
THIS PACKAGE AS THE EC/GEM TEND TO HAVE MORE SUPPORT FROM THE NAM
AND UKMET MODELS IN MEDIUM AND LONG RANGE.
BY MID WEEK...ENERGY FROM THE CURRENT SHORTWAVE TROUGH WILL GET
TRAPPED/CUT-OFF OVER MEXICO AND IT WILL BE THIS COMPLEX THAT WILL
GIVE LIFT TO THE LIMITED MOISTURE IN PLACE LATE WEDNESDAY INTO
THURSDAY. GFS IS QUICKER AS IT PHASES SOME NORTHERN STREAM ENERGY IN
BUT EC/GEM/NAM ARE SLOWER. HAVE LEANED SLOWER AND PLACED 20-40% RAIN
CHANCES FROM WEST TO EAST FROM THE 35 CORRIDOR TO THE COASTAL
PLAINS. BEST TIME-FRAME FOR RAIN WILL BEGIN LATE WEDNESDAY NIGHT
THROUGH THURSDAY AFTERNOON. WESTERN AREAS STILL APPEAR TOO DRY FOR
ANY ACCUMULATING RAINFALL. A PACIFIC FRONT WILL PUSH THROUGH THE
REGION BY EARLY FRIDAY AND END RAIN CHANCES AS THE AFOREMENTIONED CUT-
OFF ENERGY PHASES WITH A STRONGER PASSING NORTHERN STREAM TROUGH.
WITH THE BRISK H5 FLOW, THE NEXT TROUGH APPROACHES THE REGION BY
SATURDAY. PWATS WILL BE 0.3-0.4" AND IT WILL BE DIFFICULT TO HAVE
PRECIPITATION REACH THE GROUND. HAVE OPTED FOR A DRY FORECAST FOR
NOW BUT CLOUDS WILL CERTAINLY BE ON THE INCREASE SATURDAY. BY
SUNDAY...THE TROUGH WILL SHIFT EAST AND USHER IN A POSSIBLE HYBRID
PACIFIC/BACKDOOR FRONT FROM THE NORTH. THIS SHOULD KEEP US DRY
SUNDAY BUT YET ANOTHER SYSTEM WILL BE ON ITS HEELS THAT APPEARS
STRONGER AND A BETTER CHANCE OF RAIN APPEARS POSSIBLE NEXT TUESDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 53 37 63 40 62 / 10 - 0 0 10
AUSTIN BERGSTROM INTL AIRPORT 53 34 62 36 61 / 10 - 0 0 10
NEW BRAUNFELS MUNI AIRPORT 54 35 63 39 61 / 10 - 0 - 10
BURNET MUNI AIRPORT 51 34 61 37 60 / 10 0 0 0 -
DEL RIO INTL AIRPORT 55 36 62 40 61 / - 0 0 0 0
GEORGETOWN MUNI AIRPORT 52 34 61 37 60 / 10 - 0 0 10
HONDO MUNI AIRPORT 54 34 62 39 60 / 10 - 0 - 10
SAN MARCOS MUNI AIRPORT 54 36 62 38 60 / 10 - 0 - 10
LA GRANGE - FAYETTE REGIONAL 55 38 62 40 62 / 10 10 0 - 10
SAN ANTONIO INTL AIRPORT 54 37 63 40 61 / 10 - 0 - 10
STINSON MUNI AIRPORT 55 38 63 41 61 / 10 - 0 - 10
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
FREEZE WARNING UNTIL 8 AM CST THIS MORNING FOR THE FOLLOWING
COUNTIES: ATASCOSA...BEXAR...DE WITT...DIMMIT...FRIO...KARNES...
MAVERICK...WILSON...ZAVALA.
&&
$$
MESOSCALE/AVIATION...OAKS
SYNOPTIC/GRIDS...ALLEN
AREA FORECAST DISCUSSION
National Weather Service Paducah KY
308 PM CST MON JAN 11 2016
.SHORT TERM...(This evening through Thursday)
Issued at 308 PM CST MON JAN 11 2016
The main weather system of interest is a vigorous 500 mb shortwave
that will rotate southeast across the Great Lakes and mid Ohio
Valley early Tuesday morning. As this system digs southeast, a
band of strong forcing will swing southeast across our region.
Most of the model guidance indicates a band of measurable snowfall
will extend as far south as the Interstate 64 corridor by
daybreak. This precipitation will exit southwest Indiana and
adjoining parts of IL and KY by midday Tuesday. QPF from all the
models is less than a tenth of an inch, however snow to liquid
ratios will be quite high (on the order of 17 to 1). The 12z nam
and recent RAP runs suggest the highest qpf, which would
translate to an inch or two of snow along the Interstate 64
corridor. The 12z ecmwf barely brings any qpf into southwest
Indiana. Based on variability in the model qpf, will hold off on
issuing any advisories. Since this event would primarily be on
Tuesday morning, there is time for later shifts to examine radar
and satellite trends before deciding whether to pull the trigger.
The surface cold front associated with this system will sweep
southeast across our region on Tuesday morning. Gusty northwest
winds will keep temps fairly steady through the day, despite
increasing sunshine in the afternoon.
Tuesday night will be mainly clear and cold as surface high
pressure passes overhead. Lows will be in the teens. If there is a
fresh coating of snow across the Interstate 64 corridor and the
Evansville tri-state area, temps could plunge down into the single
digits there.
Wednesday into Thursday, surface high pressure will retreat
southeast to the southeast US coast as low pressure forms over
the Plains. Increasing southerly low level flow will bring milder
temps, reaching around 50 on Thursday. Plenty of clear sky is
expected during this period.
.LONG TERM...(THURSDAY NIGHT THROUGH MONDAY)
ISSUED AT 308 PM CST MON JAN 11 2016
Confidence is increasing in a precipitation event ahead of a rapidly
developing system late Thursday night and Friday, and PoPs are now
up to likely. The ECMWF and GFS generate some negative Showalter
Indices with the surge of moisture Friday. GFS soundings are not so
obvious with the elevated instability, so will leave thunder out of
the forecast for now.
The 12Z ECMWF and GFS diverge significantly with the details of
upper-level troughing beyond Friday. Both models are consistent with
their previous runs, so they currently are agreeing to disagree. Per
WPC, ECMWF solution correlates better to ridging along the west
coast, so would prefer to lean toward the ECMWF that would bring a
quick end to the precipitation Friday night. However, in respect for
the GFS, will have a slow reduction of PoPs from Friday night
through Saturday night.
It will turn much cooler again behind the initial upper system
Friday night into Saturday. If there is enough lift to generate
tangible precipitation it will likely fall as snow Saturday and
Saturday night. GFS soundings unfortunately struggle to have a deep
enough saturated layer to support pure snow, so will hedge with
rain/snow mix working eastward across the area Friday night and
Saturday. If there is anything left Saturday night it should be in
the form of light snow. It is way too early to be concerned with
measurable snow, especially considering the ECMWF is completely dry.
Another upper-level disturbance may impact the area Monday and
Monday night, but the models are not in very good agreement. Threw
in some low chance PoPs for light snow for now. Confidence is not
great in the details, but cold air and a rather active upper-level
pattern mean that more wintry precipitation is well within the realm
of possibility.
&&
.AVIATION...
Issued at 308 PM CST MON JAN 11 2016
Scattered mid level clouds will give way to an overcast deck
based around 8k feet by early this evening. A cold front will
move southeast across the taf sites early Tuesday morning,
accompanied by a wind shift from southwest to northwest. Winds
will remain gusty both ahead of and behind the front. Cigs will
gradually lower as the front approaches, and some mvfr cigs are
likely along and immediately behind the front. There will be some
snow or snow showers in the kevv/kowb areas along the front,
producing lower vsbys. IFR conditions are possible in any heavier
snow showers, but are not likely at this time.
&&
.PAH Watches/Warnings/Advisories...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
SHORT TERM...MY
LONG TERM...DRS
AVIATION...MY
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
503 PM EST MON JAN 11 2016
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 439 PM EST MON JAN 11 2016
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW A DEEP MID/UPPER TROF
EXTENDING FROM HUDSON BAY S THRU THE UPPER MISSISSIPPI VALLEY AND
GREAT LAKES REGION DOWNSTREAM OF A RIDGE EXTENDING ALONG THE W COAST
OF CANADA THRU NE ALASKA. A RATHER VIGOROUS LOOKING SHORTWAVE IS
DROPPING SE THRU ERN ND/NW MN. ANOTHER WEAKER SHORTWAVE TROF IS
SWINGING S THRU NRN MANITOBA. THESE 2 FEATURES...ESPECIALLY THE
FIRST SHORTWAVE...WILL DRIVE THE FCST IN THE SHORT TERM. WITH LATEST
RAP ANALYSIS SHOWING 850MB TEMPS AROUND -20C ACROSS LAKE SUPERIOR...
LES CONTINUES. HOWEVER...BACKING WINDS IN RESPONSE TO THE
APPROACHING SHORTWAVE HAS RESULTED IN LES BANDS SHIFTING OFFSHORE OF
MORE OF UPPER MI DURING THE DAY. ALTHOUGH CLOUD TOPS WERE UP TO
AROUND 10KFT PER KMQT RADAR EARLIER TODAY...THE SHIFTING WINDS...
LACK OF WELL ORGANIZED BANDS...AND A MORE SUPPRESSED DGZ TO THE
LOWER PART OF THE CONVECTIVE LAYER HAVE KEPT SNOW ACCUMULATIONS IN
CHECK.
WITH LES ALREADY ONGOING ACROSS LAKE SUPERIOR...APPROACHING
SHORTWAVE WILL RESULT IN THE NORMAL INTENSIFICATION OF LES
TONIGHT/TUE MORNING. WINDS WILL CONTINUE TO BACK OVER THE NEXT FEW
HRS IN RESPONSE TO THE STRONGER SHORTWAVE DROPPING SE THRU MN.
THEN AS SFC TROF ASSOCIATED WITH SHORTWAVE MOVES S OVER LAKE
SUPERIOR...A SHARPER CONVERGENCE ZONE WILL DEVELEOP THIS EVENING...
RUNNING FROM NEAR THE APOSTLE ISLANDS TO N OF COPPER HARBOR THEN
OVER TO MICHIPICOTEN ISLAND. CONVERGENCE ZONE SHOULD ALSO HELP LIFT
DGZ A BIT HIGHER INTO THE CONVECTIVE LAYER TO INCREASE SNOW-TO-WATER
RATIOS. ALTHOUGH THE TRACK OF THE SHORTWAVE IS A BIT FARTHER S THAN
IDEAL (PEAK DEEP LAYER FORCING PASSES S OF LAKE SUPERIOR)...SYNOPTIC
FORCING/DEEP MOISTURE WILL BE MORE THAN SUFFICIENT TO AID
DEVELOPMENT OF HVY SNOW ALONG THE CONVERGENCE ZONE THAT WILL DROP S
TONIGHT/EARLY TUE MORNING. WITH WINDS AT LEAST BRIEFLY SHIFTING
NNW/N WITH PASSAGE OF SFC TROF...ALL LOCATIONS ALONG LAKE SUPERIOR
WILL SEE AT LEAST A BRIEF BURST OF MDT/HVY SNOW. AREA FROM KIWD TO
AROUND THE PORCUPINE MOUNTAINS AND FROM VCNTY OF MARQUETTE OVER THE
GRAND MARAIS SHOULD SEE THE HEAVIEST SNOW WITH THE TROF PASSAGE.
KEWEENAW COUNTY MAY ALSO END UP WITH SOME OF THE HEAVIEST SNOW DUE
TO LONG FETCH HVY SNOW BAND INITIATING NEAR THE APOSTLE ISLANDS
ALONG THE SFC TROF. LOCAL HIRES WRF RUN AND CANADIAN HIGH RES RUNS
BOTH HAVE A HIGHER PCPN SIGNATURE IN KEWEENAW COUNTY. SO...LES ADVYS
WILL REMAIN UP FROM GOGEBIC COUNTY THRU THE KEWEENAW.
MARQUETTE/ALGER COUNTIES WILL ALSO BE ADDED. THE FACT THAT THE HVY
SNOW/GUSTY WINDS ARRIVE JUST BEFORE AND DURING THE MORNING COMMUTE
SHOULD LEAD TO ESPECIALLY DIFFICULT DRIVING CONDITIONS TUE MORNING
FOR MARQUETTE/ALGER COUNTIES. MAY NEED TO CONSIDER ADDING NRN
SCHOOLCRAFT/LUCE COUNTIES TO ADVY FOR TUE...BUT RIGHT NOW HAVE SNOW
ACCUMULATIONS NEAR/JUST UNDER ADVY CRITIERIA.
WIND PARALLEL LES BANDS WILL SET UP A FEW HRS AFTER THE TROF PASSES
AND WILL THEN SLOWLY SHIFT THRU THE DAY TUE AS WINDS BACK WNW OVER
WRN LAKE SUPERIOR AND NW OVER ERN LAKE SUPERIOR. TOTAL SNOW
ACCUMULATIONS TONIGHT/TUE WILL GENERALLY RANGE FROM 2 TO 7 INCHES
ALONG LAKE SUPERIOR WITH HIGHEST AMOUNTS VCNTY OF THE PORCUPINE MTNS
AND JUST E OF MARQUETTE TO PICTURED ROCKS.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 502 PM EST MON JAN 11 2016
NW WINDS WILL CONTINUE TUESDAY NIGHT WITH AN ADDITIONAL 2-5IN
EXPECTED FROM THE PORCUPINE MTNS UP THROUGH CALUMET...AND THEN NE OF
A LINE FROM MUNISING TO NEWBERRY. MOISTURE QUICKLY SHIFTS N
WEDNESDAY AS A MORE W WIND TAKES OVER...LIMITING ADDITIONAL SNOW
AMOUNTS TO THE KEWEENAW AND THEN RIGHT ALONG THE LAKE SUPERIOR
SHORELINE FROM GRAND MARAIS TO WHITEFISH POINT. THIS WILL BE ALL
WHILE THE MAIN SFC LOW EXITS FROM THE LOWER GREAT LAKES TO THE NEW
ENGLAND STATES...AND RIDGING TRIES TO PUSH IN FROM THE SW. A TROUGH
LOOKS TO LINGER ACROSS CENTRAL AND E LAKE SUPERIOR...ALONG WITH
850MB TEMPS OF -15 TO -22C...AND AN ELONGATED SHORTWAVE IN THE NW
FLOW ALOFT...KEEPING LES GOING.
KEPT ONLY CHANCE LES FOR WEDNESDAY NIGHT OVER THE KEWEENAW AS THE
BEST MOISTURE EXITS AND SLIGHT RIDGING TAKES PLACE AT 500MB. THERE
IS SOME POTENTIAL FOR WAA SNOW THURSDAY OUT AHEAD OF THE ORGANIZING
SFC LOW TO OUR W AND SW. BETTER DETAILS ARE EXPECTED WITH THIS
FEATURE...AND A QUICK BURST OF SNOW OVER THE S HALF OF THE CWA COULD
BE POSSIBLE.
TIMING FOR WHEN AND WHERE THE EJECTING SFC LOW WILL BE LATE THIS
WEEK AND EARLY THIS WEEKEND ARE SILL A CONCERN. AT 18Z FRIDAY THE
LOW IS CENTERED SOMEWHERE BETWEEN IL AND AR...AND COULD MOVE OVER
THE GREAT LAKES AND OFF THE EASTERN SEABORARD BY 12Z SATURDAY. THIS
QUICKER SOLUTION IS OFF THE 12Z ECMWF. A WETTER SOLUTION FOR US IS A
SLOWER MORE W TRACK...SIMILAR TO THE GFS AND CANADIAN WITH THE THE
LOW OVER IN AT 12Z SATURDAY. EITHER WAY...WE MAY HAVE A PERIOD OF N
WINDS LATE CENTERING SOME SNOW SHOWERS ACROSS N CENTRAL UPPER MI
FRIDAY NIGHT-SATURDAY. INCLUDED LIKELY POPS FOR SATURDAY...BEFORE
TRANSITIONING TO A MORE NNW-NW FLOW PATTERN AGAIN SATURDAY NIGHT ON.
FEW OTHER CHANGES WERE MADE TO A BLENDED SOLUTION IN THE DAYS 4-7
FCST.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1230 PM EST MON JAN 11 2016
WITH WINDS BACKING TO THE SW THIS AFTN AHEAD OF AN APPROACHING
DISTURBANCE...VFR CONDITIONS WILL PREVAIL AT KIWD/KSAW. AT KCMX...
MOST OF THE LAKE EFFECT -SHSN WILL SHIFT N OF THE TERMINAL IN THE
NEXT FEW HRS...BRINGING AN END TO OCNL IFR CONDITIONS. MVFR/OCNL VFR
CONDITIONS WILL THEN BE THE RULE THRU LATE AFTN. TONIGHT...A LOW
PRES TROF WILL DROP S ACROSS LAKE SUPERIOR AND INTO UPPER MI...
BRINGING A WSHFT TO THE NNW. WHILE THERE MAY BE SOME -SN WITH
MVFR/IFR CONDITIONS AHEAD OF IT...IN ITS WAKE...HEAVY LAKE EFFECT
SNOW SHOWERS WILL BRING A PERIOD OF LIFR CONDITIONS TO ALL TERMINALS
OVERNNIGHT/EARLY TUE MORNING. ALTHOUGH CONDITIONS WILL LIKELY REMAIN
A PREVAILING LIFR AT KIWD/KCMX TUE MORNING...SLIGHT BACKING OF WINDS
SHOULD SHIFT HEAVIER SNOW SHOWERS E OF KSAW LATE IN THE MORNING...
RESULTING IN A RETURN OF MVFR CONDITIONS.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 502 PM EST MON JAN 11 2016
MUCH OF THIS PERIOD WILL BE MARKED BY AN AREA OF LOW PRESSURE OVER
LAKE SUPERIOR. LOW PRESSURE INITIALLY ACROSS LAKE SUPERIOR AND WI
WILL DEEPEN OVER S LAKE HURON BY TUESDAY MORNING. NNW WINDS TO 30
KTS EXPECTED TONIGHT...WITH WITH SOME GALE FORCE GUSTS UP TO 35 KTS.
THE LOW WILL EXIT ALONG S QUEBEC AND THE NEW ENGLAND STATES LATE IN
THE DAY...AS THE LINGERING TROUGH OVER LAKE SUPERIOR WEAKENS
SLIGHTLY AND HIGH PRESSURE BUILDS INTO THE MISSISSIPPI VALLEY
TUESDAY NIGHT INTO WEDNESDAY. ANOTHER ROUND OF COLD AIR SINKING IN
WILL BRING ANOTHER PERIOD OF HEAVY FREEZING SPRAY TO W AND N CENTRAL
LAKE SUPERIOR LATE TONIGHT AND TUESDAY.
LOW PRESSURE OVER FAR N MANITOBA...AND AN ADDITIONAL LOW OVER S
ALBERTA WEDNESDAY EVENING WILL COMBINE AND SETTLE ACROSS THE CENTRAL
PLAINS THURSDAY NIGHT. EXPECT THE SURFACE LOW TO LIFT NORTHEAST
ACROSS THE LOWER GREAT LAKES SATURDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY FROM 5 AM TO 7 PM EST TUESDAY FOR
MIZ006.
LAKE EFFECT SNOW ADVISORY FROM 10 PM EST /9 PM CST/ THIS EVENING
TO 4 PM EST /3 PM CST/ TUESDAY FOR MIZ001>003-009.
LAKE EFFECT SNOW ADVISORY FROM 5 AM TO 1 PM EST TUESDAY FOR
MIZ005.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING FROM 3 AM TO 3 PM EST TUESDAY FOR
LSZ248-249-265-266.
HEAVY FREEZING SPRAY WARNING FROM 2 AM EST /1 AM CST/ TO 1 PM
EST /NOON CST/ TUESDAY FOR LSZ241>244-263-264.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...KF
AVIATION...ROLFSON
MARINE...KF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
440 PM EST MON JAN 11 2016
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 439 PM EST MON JAN 11 2016
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW A DEEP MID/UPPER TROF
EXTENDING FROM HUDSON BAY S THRU THE UPPER MISSISSIPPI VALLEY AND
GREAT LAKES REGION DOWNSTREAM OF A RIDGE EXTENDING ALONG THE W COAST
OF CANADA THRU NE ALASKA. A RATHER VIGOROUS LOOKING SHORTWAVE IS
DROPPING SE THRU ERN ND/NW MN. ANOTHER WEAKER SHORTWAVE TROF IS
SWINGING S THRU NRN MANITOBA. THESE 2 FEATURES...ESPECIALLY THE
FIRST SHORTWAVE...WILL DRIVE THE FCST IN THE SHORT TERM. WITH LATEST
RAP ANALYSIS SHOWING 850MB TEMPS AROUND -20C ACROSS LAKE SUPERIOR...
LES CONTINUES. HOWEVER...BACKING WINDS IN RESPONSE TO THE
APPROACHING SHORTWAVE HAS RESULTED IN LES BANDS SHIFTING OFFSHORE OF
MORE OF UPPER MI DURING THE DAY. ALTHOUGH CLOUD TOPS WERE UP TO
AROUND 10KFT PER KMQT RADAR EARLIER TODAY...THE SHIFTING WINDS...
LACK OF WELL ORGANIZED BANDS...AND A MORE SUPPRESSED DGZ TO THE
LOWER PART OF THE CONVECTIVE LAYER HAVE KEPT SNOW ACCUMULATIONS IN
CHECK.
WITH LES ALREADY ONGOING ACROSS LAKE SUPERIOR...APPROACHING
SHORTWAVE WILL RESULT IN THE NORMAL INTENSIFICATION OF LES
TONIGHT/TUE MORNING. WINDS WILL CONTINUE TO BACK OVER THE NEXT FEW
HRS IN RESPONSE TO THE STRONGER SHORTWAVE DROPPING SE THRU MN.
THEN AS SFC TROF ASSOCIATED WITH SHORTWAVE MOVES S OVER LAKE
SUPERIOR...A SHARPER CONVERGENCE ZONE WILL DEVELEOP THIS EVENING...
RUNNING FROM NEAR THE APOSTLE ISLANDS TO N OF COPPER HARBOR THEN
OVER TO MICHIPICOTEN ISLAND. CONVERGENCE ZONE SHOULD ALSO HELP LIFT
DGZ A BIT HIGHER INTO THE CONVECTIVE LAYER TO INCREASE SNOW-TO-WATER
RATIOS. ALTHOUGH THE TRACK OF THE SHORTWAVE IS A BIT FARTHER S THAN
IDEAL (PEAK DEEP LAYER FORCING PASSES S OF LAKE SUPERIOR)...SYNOPTIC
FORCING/DEEP MOISTURE WILL BE MORE THAN SUFFICIENT TO AID
DEVELOPMENT OF HVY SNOW ALONG THE CONVERGENCE ZONE THAT WILL DROP S
TONIGHT/EARLY TUE MORNING. WITH WINDS AT LEAST BRIEFLY SHIFTING
NNW/N WITH PASSAGE OF SFC TROF...ALL LOCATIONS ALONG LAKE SUPERIOR
WILL SEE AT LEAST A BRIEF BURST OF MDT/HVY SNOW. AREA FROM KIWD TO
AROUND THE PORCUPINE MOUNTAINS AND FROM VCNTY OF MARQUETTE OVER THE
GRAND MARAIS SHOULD SEE THE HEAVIEST SNOW WITH THE TROF PASSAGE.
KEWEENAW COUNTY MAY ALSO END UP WITH SOME OF THE HEAVIEST SNOW DUE
TO LONG FETCH HVY SNOW BAND INITIATING NEAR THE APOSTLE ISLANDS
ALONG THE SFC TROF. LOCAL HIRES WRF RUN AND CANADIAN HIGH RES RUNS
BOTH HAVE A HIGHER PCPN SIGNATURE IN KEWEENAW COUNTY. SO...LES ADVYS
WILL REMAIN UP FROM GOGEBIC COUNTY THRU THE KEWEENAW.
MARQUETTE/ALGER COUNTIES WILL ALSO BE ADDED. THE FACT THAT THE HVY
SNOW/GUSTY WINDS ARRIVE JUST BEFORE AND DURING THE MORNING COMMUTE
SHOULD LEAD TO ESPECIALLY DIFFICULT DRIVING CONDITIONS TUE MORNING
FOR MARQUETTE/ALGER COUNTIES. MAY NEED TO CONSIDER ADDING NRN
SCHOOLCRAFT/LUCE COUNTIES TO ADVY FOR TUE...BUT RIGHT NOW HAVE SNOW
ACCUMULATIONS NEAR/JUST UNDER ADVY CRITIERIA.
WIND PARALLEL LES BANDS WILL SET UP A FEW HRS AFTER THE TROF PASSES
AND WILL THEN SLOWLY SHIFT THRU THE DAY TUE AS WINDS BACK WNW OVER
WRN LAKE SUPERIOR AND NW OVER ERN LAKE SUPERIOR. TOTAL SNOW
ACCUMULATIONS TONIGHT/TUE WILL GENERALLY RANGE FROM 2 TO 7 INCHES
ALONG LAKE SUPERIOR WITH HIGHEST AMOUNTS VCNTY OF THE PORCUPINE MTNS
AND JUST E OF MARQUETTE TO PICTURED ROCKS.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 309 AM EST MON JAN 11 2016
THE START OF THE LONG TERM FORECAST WILL CONTAIN THE MOST IMPACTFUL
WEATHER...BEFORE TRANSITIONING BACK TO TRADITIONAL LAKE EFFECT FOR
THE MIDDLE OF THE WEEK AND THEN MORE NORMAL TEMPERATURES AND
POSSIBLY SOME SYNOPTIC SNOW OR MORE LAKE EFFECT SNOW BY NEXT
WEEKEND.
FOR THE START OF THE PERIOD...A SHORTWAVE CURRENTLY IN THE NORTHWEST
TERRITORIES WILL BE DIVING SOUTHEAST TODAY AND MOVING INTO
WISCONSIN THIS EVENING. AS THAT OCCURS...IT WILL CATCH UP WITH A
SECONDARY SHORTWAVE (ASSOCIATED WITH A SURFACE LOW DEPARTING EASTERN
IOWA) AND LEAD TO A RAPID DEEPENING OF THE LOW AFTER MIDNIGHT
TONIGHT WHILE MOVING ACROSS LOWER MICHIGAN AND INTO LAKE HURON.
WHILE THAT IS OCCURRING...A LAKE INDUCED LOW WILL DEVELOP OVER
EASTERN LAKE SUPERIOR WITH A TROUGH STRETCHING WEST ACROSS THE
WESTERN HALF OF THE LAKE THIS EVENING. EXPECT THERE TO BE ONGOING
LAKE EFFECT IN THE WEST-SOUTHWEST WIND AREAS AS THE TROUGH AND LOW
DEVELOPS AND THE SHORT TERM FORECAST WILL HANDLE THE DETAILS WITH
THAT AS IT DROPS SOUTH. AS THE LONG TERM FORECAST STARTS...THE
TROUGH SHOULD HAVE ALREADY DROPPED SOUTH ACROSS LAKE SUPERIOR AND
WILL BE MOVING THROUGH CENTRAL AND SOUTHERN UPPER MICHIGAN.
THUS...THE AREAS FAVORED BY NORTHERLY WINDS OVER THE NORTH CENTRAL
AND NORTH-NORTHWESTERLY WINDS OVER THE WEST WILL BE EXPERIENCING
MODERATE TO HEAVY LAKE EFFECT SNOW WITH THE VERY FAVORABLE
CONDITIONS (INVERSION HEIGHTS TO 13KFT...LAKE INDUCED CAPE AROUND
800 J/KG...AND INCREASED CONVERGENCE IMMEDIATELY BEHIND THE FRONT).
EXPECT THAT TO CONTINUE THROUGH THE MORNING HOURS ON TUESDAY BEFORE
WINDS BEGIN TO SLOWLY BACK AND INVERSION HEIGHTS STEADILY FALL DUE
TO AN APPROACHING HIGH PRESSURE RIDGE. THINK THE FALLING INVERSION
HEIGHTS WILL AFFECT THE WESTERN CWA THE MOST (FALLING TO 8KFT BY
00Z AND THEN TO 6KFT BY 12Z WEDNESDAY) WHILE THE INCREASED LAKE
MODERATION SHOULD KEEP CONDITIONS A LITTLE MORE FAVORABLE. WHILE
THE LOWERING INVERSION HEIGHTS AND BACKING WINDS SHOULD KEEP SNOW
AMOUNTS FROM BECOMING TOO SIGNIFICANT...DO EXPECT VERY POOR
CONDITIONS FOR THE NORTH CENTRAL (SPECIFICALLY EASTERN MARQUETTE
AND ALGER COUNTIES...POSSIBLY NOSING INTO NORTHEASTERN DELTA
COUNTY) AIDED BY THE LONGER FETCH AND NORTHERLY WINDS GUSTING TO
AROUND 30KTS LEADING TO SIGNIFICANT BLOWING SNOW AND DRASTICALLY
REDUCED VISIBILITIES AT TIMES. AFTER COORDINATION WITH THE SHORT
TERM FORECASTER...DECIDED TO HOLD OFF ON ANY HEADLINES FOR THE
NORTH CENTRAL SO THE EXISTING ALGER COUNTY HEADLINE CAN EXPIRE.
WILL ADD WORDING TO THE EXISTING WSW TO ADDRESS THE EXPECTED
CONDITIONS LATE MONDAY NIGHT INTO TUESDAY MORNING.
THE LAKE EFFECT SNOW WILL CONTINUE INTO WEDNESDAY AS THE HIGH
PRESSURE RIDGE TO THE SOUTH OF THE AREA CONTINUES TO BACK WINDS TO
THE WEST-NORTHWEST. ANOTHER WEAK SHORTWAVE SLIDING ACROSS THE AREA
WEDNESDAY MORNING WILL GIVE A BRIEF REPRIEVE TO THE FALLING
INVERSION HEIGHTS AND GIVE A BOOST TO THE LAKE EFFECT FOR THE
WEST-NORTHWEST WIND AREAS. WITH TEMPERATURES ALOFT STARTING TO
MODERATE WEDNESDAY AFTERNOON INTO WEDNESDAY NIGHT...THE CLOUD LAYER
WILL BE FALLING MORE WITHIN THE DGZ AND HELP TO INCREASE SNOW RATIOS
AND LEAD TO FLUFFIER SNOW WHERE THE DOES OCCUR (WEST-NORTHWEST IN
THE AFTERNOON AND BACKING WESTERLY INTO WEDNESDAY NIGHT).
THE REST OF THE FORECAST WILL FOCUS ON THE DEVELOPMENT OF A SURFACE
LOW IN THE NORTHERN/CENTRAL PLAINS AND THE SURFACE TROUGH THAT WILL
STRETCH NORTHEAST INTO THE GREAT LAKES REGION. MODELS ARE SHOWING
SOME SNOW OCCURRING ON THE NORTHERN EDGE OF THIS TROUGH (NORTHERN
WISCONSIN OR OVER THE U.P.) THURSDAY NIGHT INTO FRIDAY MORNING ON
THE LEADING EDGE OF THE MID LEVEL WARM AIR ADVECTION. MODELS VARY ON
THE EXACT SOLUTION FOR FRIDAY INTO SATURDAY...BUT THE GENERAL IDEA
IS FOR THE TROUGH TO BECOME ESTABLISHED SOMEWHERE OVER MICHIGAN
(LEADING TO LIGHT SNOW) AND THEN A SHORTWAVE ROUNDING THE BASE OF
THE TROUGH ON FRIDAY WILL STRENGTHEN THE LOW IN THE CENTRAL/SOUTHERN
PLAINS AND LIFT IT NORTHEAST THROUGH THE GREAT LAKES REGION. AT THIS
POINT...THE 00Z GFS IS THE FARTHEST TO THE NORTHWEST AND TRACKS THE
LOW THROUGH THE EASTERN U.P. (00Z ENSEMBLE MEAN HAS IT IN CENTRAL
LOWER MICHIGAN) WHILE THE 00Z GEM HAS IT CROSS LAKE ERIE AND THE
00Z ECWMF TRENDED NW TOWARDS THE GEM (12Z DETERMINISTIC AND
ENSEMBLES HAD IT MORE IN THE MID ATLANTIC STATES). THE DIFFERENCES
ARE TIED TO PHASING OF THE INITIAL SHORTWAVE LIFTING NORTHEAST
TOWARDS THE GREAT LAKES AND SECOND WAVE ROUNDING THE BASE OF THE
UPPER TROUGH...WHICH WILL LIKELY GO THROUGH SEVERAL ADJUSTMENTS
OVER THE COMING DAYS. IF THE GFS SOLUTION IS CORRECT...WOULD EXPECT
A DECENT SNOWFALL...WHILE THE GEM/ECMWF WOULD PUT THE AREA UNDER
LIGHT NORTH-NORTHEASTERLY FLOW LAKE EFFECT. SINCE IT IS STILL A LONG
WAYS OUT...JUST OPTED TO FOLLOW THE CONSENSUS OF THE MODELS WITH THE
GREATEST CHANCE POPS IN THE NORTH-NORTHEAST WIND FAVORED LOCATIONS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1230 PM EST MON JAN 11 2016
WITH WINDS BACKING TO THE SW THIS AFTN AHEAD OF AN APPROACHING
DISTURBANCE...VFR CONDITIONS WILL PREVAIL AT KIWD/KSAW. AT KCMX...
MOST OF THE LAKE EFFECT -SHSN WILL SHIFT N OF THE TERMINAL IN THE
NEXT FEW HRS...BRINGING AN END TO OCNL IFR CONDITIONS. MVFR/OCNL VFR
CONDITIONS WILL THEN BE THE RULE THRU LATE AFTN. TONIGHT...A LOW
PRES TROF WILL DROP S ACROSS LAKE SUPERIOR AND INTO UPPER MI...
BRINGING A WSHFT TO THE NNW. WHILE THERE MAY BE SOME -SN WITH
MVFR/IFR CONDITIONS AHEAD OF IT...IN ITS WAKE...HEAVY LAKE EFFECT
SNOW SHOWERS WILL BRING A PERIOD OF LIFR CONDITIONS TO ALL TERMINALS
OVERNNIGHT/EARLY TUE MORNING. ALTHOUGH CONDITIONS WILL LIKELY REMAIN
A PREVAILING LIFR AT KIWD/KCMX TUE MORNING...SLIGHT BACKING OF WINDS
SHOULD SHIFT HEAVIER SNOW SHOWERS E OF KSAW LATE IN THE MORNING...
RESULTING IN A RETURN OF MVFR CONDITIONS.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 447 AM EST MON JAN 11 2016
NW WINDS UP TO 30 KTS OVER MAINLY THE E HALF OF THE LAKE THIS
MORNING WILL BACK TO THE W AND DIMINISH TO AROUND 20 KTS THIS
AFTERNOON AS A HI PRES RIDGE MOVES THRU THE OH RIVER VALLEY. THE
WINDS WILL VEER BACK TO THE NNW LATER TONIGHT AND INCREASE UP TO 30
KTS WITH SOME GALE FORCE GUSTS UP TO 35 KTS AS THE PRES GRADIENT
TIGHTENS AGAIN OVER THE UPPER LAKES FOLLOWING THE PASSAGE OF A LO
PRES THRU THE CENTRAL GREAT LAKES. WITH MUCH COLDER AIR RUSHING BACK
INTO THE AREA...HEAVY FREEZING SPRAY WILL ALSO DEVELOP OVER PORTIONS
OF WESTERN AND NORTH CENTRAL LAKE SUPERIOR LATE TONIGHT AND TUE. AS
THE GRADIENT SLACKENS TUE NIGHT INTO WED...EXPECT THE STRONGER WINDS
AND FREEZING SPRAY TO SUBSIDE. LIGHTER WINDS UNDER 25 KTS WILL
DOMINATE THE LATE WEEK PERIOD.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY FROM 5 AM TO 7 PM EST TUESDAY FOR
MIZ006.
LAKE EFFECT SNOW ADVISORY FROM 10 PM EST /9 PM CST/ THIS EVENING
TO 4 PM EST /3 PM CST/ TUESDAY FOR MIZ001>003-009.
LAKE EFFECT SNOW ADVISORY FROM 5 AM TO 1 PM EST TUESDAY FOR
MIZ005.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING FROM 3 AM TO 3 PM EST TUESDAY FOR
LSZ248-249-265-266.
HEAVY FREEZING SPRAY WARNING FROM 2 AM EST /1 AM CST/ TO 1 PM
EST /NOON CST/ TUESDAY FOR LSZ241>244-263-264.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...SRF
AVIATION...ROLFSON
MARINE...KC
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
405 PM EST MON JAN 11 2016
LATEST UPDATE...
MARINE
.SYNOPSIS...
ISSUED AT 305 PM EST MON JAN 11 2016
A WAVE OF LOW PRESSURE WILL DEEPEN AS IT TRACKS EASTWARD THROUGH
LOWER MICHIGAN TONIGHT. SNOW WILL INCREASE ACROSS THE REGION AS A
RESULT AND COULD BE HEAVY. THE SNOW WILL PERSIST THROUGH TUESDAY
WITH LOCALLY HEAVY SNOW ESPECIALLY CLOSE TO LAKE MICHIGAN.
HAZARDOUS TRAVEL IS EXPECTED FOR MOST AREA THROUGH TUESDAY.
ARCTIC AIR WILL CONTINUE TO FLOW INTO THE REGION ON WEDNESDAY WITH
ADDITIONAL LAKE EFFECT SNOW POSSIBLE.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT)
ISSUED AT 305 PM EST MON JAN 11 2016
COMMONLY WITH A DIGGING SYNOPTIC WAVE FOLLOWED BY AN ARCTIC
AIRMASS WE TEND TO SEE WIDESPREAD IMPACTS...SOMETIMES SIGNIFICANT
IMPACTS. THUS I WENT WITH A WARNING FOR MUCH OF THE LAKESHORE
REGION AND A FEW INLAND COUNTIES AS WELL.
THE LOW LEVEL FLOW BACKS THIS EVENING AS THE WAVE APPROACHES. THIS
WILL ACT TO FOCUS THE MAIN BAND WEST OF KENT COUNTY DUE TO THE
FLOW BECOMING SOUTHEAST OVER GRAND RAPIDS THIS EVENING. AS A
RESULT IT APPEARS KENT COUNTY WILL MISS MUCH OF THIS INITIAL
BANDING THIS EVENING...SO I DID NOT INCLUDE KENT IN THE WARNING. SOME
NEWER MODELS ACTUALLY TAKE THE BANDING WEST OF MUSKEGON. THIS
WOULD BE UNUSUAL. THE FLOW VEERS NORTHWEST BY 12Z TUE. THE
TUESDAY MORNING COMMUTE LOOKS QUITE IMPACTED AS THE BANDS SHIFT
AND HEAVY SNOW SHOWERS PERSIST. ALSO THE WINDS WILL INCREASE LATE
TONIGHT ALONG THE LAKESHORE AND ALL LOCATIONS ON TUESDAY. BLOWING
SNOW WILL INCREASE. I NOTICED THE LATEST HRRR RUC HAD GREATER THAN
35 KNOTS ON THE LAKESHORE. THIS COMBINED WITH HEAVY SNOW BANDS
SHOULD SUPPORT NEAR WHITEOUT CONDITIONS.
I EXTENDED THE HEADLINES INLAND. THE STRONGER WINDS WILL ACT TO
CARRY THE SNOW SHOWERS WELL INLAND. THAT COMBINED WITH WIND GUSTS
OVER 20 KNOTS WILL SUPPORT HAZARDOUS TRAVEL AT TIMES ON TUESDAY.
.LONG TERM...(THURSDAY THROUGH MONDAY)
ISSUED AT 305 PM EST MON JAN 11 2016
MAIN CONCERN CONTINUES TO BE WINTER WEATHER FRIDAY NIGHT. MOST MODEL
GUIDANCE INDICATES LIMITED SNOWFALL WITH THIS EVENT DUE TO STRONG
LOW LEVEL WARM ADVECTION AHEAD OF THE SURFACE LOW. AS NOTED IN THE
PREVIOUS DISCUSSION...THE GFS HAS BEEN INCONSISTENT RUN TO RUN.
HOWEVER THE GFS PARALLEL...GEM...AND FIM ALL FAVOR A WARMER SOLUTION
MORE CONSISTENTLY.
AS NOTED ALREADY...THE DETERMINISTIC ECMWF SHOWS GOOD RUN TO RUN
CONSISTENCY WITH A LOW TRACK INTO THE OHIO VALLEY FAVORABLE FOR SNOW
OVER THE FORECAST AREA. HOWEVER...THIS CONTROL RUN IS AN OUTLIER
RELATIVE TO MOST ENSEMBLE MEMBERS THAT SHOW LOW TRACKS EITHER OVER
LOWER MICHIGAN OR MUCH FARTHER SOUTHEAST.
ALL THAT SAID...THERE ARE GOOD REASONS PUT FORTH IN THE PREVIOUS
DISCUSSION TO NOT DISCOUNT THE DETERMINISTIC ECMWF ENTIRELY AND TO
CONTINUE WATCHING THIS.
WHAT IS MORE CERTAIN IS SIGNIFICANT PRECIPITATION FALLING ON A
DECENT SNOWPACK BY THE END OF THE WEEK...RAISING CONCERNS FOR RIVERS
THAT ARE DISCUSSED IN DETAIL IN THE HYDROLOGY SECTION.
A FINAL CONCERN IS THE POTENTIAL FOR LIGHT FREEZING RAIN FRIDAY
MORNING AS DEEP MOISTURE OVERSPREADS SURFACE AIR TEMPERATURES IN THE
MID TO UPPER 20S. THIS COULD AFFECT THE FRIDAY MORNING COMMUTE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 104 PM EST MON JAN 11 2016
THROUGH 21Z...MAIN CONCERN IS A PERSISTENT EAST TO WEST SNOW BAND IMPACTING
PRIMARILY THE KGRR TERMINAL WITH IFR VSBY. THIS BAND SHOULD DRIFT
NORTH WITH GRADUALLY IMPROVING CONDITIONS AT THE GRR AND MKG TERMINALS.
BEGINNING AROUND 00Z...A RAPID REDUCTION TO IFR VSBY CAN BE
EXPECTED BY THE LAKESHORE AS AN INTENSE AREA OF SNOW DEVELOPS.
SNOW WILL SPREAD EASTWARD AS WINDS SHIFT TO THE WEST AND
STRENGTHEN. VISIBILITIES WILL BE HIGHLY VARIABLE ESPECIALLY
BETWEEN 00Z-10Z DUE TO PASSING SNOW BANDS.
EXPECT A TRANSITION TO MORE WIDESPREAD IFR OR FUEL ALTERNATE MVFR
VSBYS IS EXPECTED AFTER 12Z WITH BLOWING SNOW AN INCREASING
CONCERN...ESPECIALLY NEAR THE LAKESHORE.
&&
.MARINE...
ISSUED AT 405 PM EST MON JAN 11 2016
EXTENDED THE SCA INTO WEDNESDAY GIVEN INCREASING WINDS FROM THE
NORTHWEST OVERNIGHT AND ASSOCIATED WAVE GROWTH. WE COULD EASILY
COULD SEE SOME GUSTS OVER 35 OR 40 KNOTS AND WERE CONSIDERING A
GALE WARNING WITH THIS FORECAST. THIS WILL BE SOMETHING TO WATCH
FOR THE NEXT UPDATE. REGARDLESS...IT WILL GET QUITE UNPLEASANT ON
LAKE MICHIGAN OVERNIGHT WITH SNOW AND FREEZING SPRAY.
&&
.HYDROLOGY...
ISSUED AT 1121 AM EST MON JAN 11 2016
MINOR RIVER FLOODING IS ONGOING AT HOLT...MAPLE RAPIDS AND IONIA.
THE MAPLE RIVER AT MAPLE RAPIDS WILL CONTINUE TO GRADUALLY CLIMB
OVER THE NEXT COUPLE OF DAYS BEFORE STABILIZING. HOLT AND IONIA
HAVE BEGUN TO SHOW DECLINE. IMPROVEMENT SHOULD CONTINUE.
MANY OTHER SITES THROUGH SOUTHWEST LOWER MICHIGAN ARE FLOWING
WELL BELOW ACTION STAGE WHILE THE RISES AND HIGHER LEVELS ARE
CONCENTRATED SOUTH AND EAST OF GRAND RAPIDS. THESE ARE THE SAME
AREAS THAT WERE MORE SO AFFECTED BY MILD WEATHER AND RAINFALL
EARLY IN THE WEEKEND. GOING FORWARD...OVERALL STABILIZATION OR
IMPROVEMENT IS ANTICIPATED IN THE GRAND SCHEME OF THINGS. CONCERNS
ARE MINOR...WHICH INCLUDE THE ACTIVE WEATHER PATTERN AND ARCTIC
AIR MASS.
PRECIPITATION CHANCES EXIST AT SOME POINT EACH DAY OF THE WEEK.
THE GOOD NEWS IS THAT IT WILL ALL LIKELY BE IN THE FORM OF SNOW.
THE DOWN SIDE WITH THESE TEMPERATURES IS THE RISING CONCERN FOR
ICE FORMATION...ESPECIALLY IN CENTRAL LOWER MICHIGAN WHERE
TEMPERATURES HAVE BEEN COLDER FOR A LONGER PERIOD OF TIME. THIS
MAY BE THE WEEK WHERE WE SEE SOME ISSUES DEVELOP WITH MINOR ICE
JAMMING...ESPECIALLY ON LOWER VOLUME RIVERS THAT FREEZE UP IN A
QUICKER FASHION. IT IS NOTHING OF ALARM AT THIS POINT...BUT JUST
SOMETHING TO KEEP AN EYE ON WITH OVERNIGHT TEMPS IN THE SINGLE
DIGITS.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...WINTER STORM WARNING FROM 7 PM THIS EVENING TO 7 PM EST TUESDAY
FOR MIZ037-038-043-044-050-056-064-071-072.
WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 7 PM EST
TUESDAY FOR MIZ057-058-065-066-073.
WINTER WEATHER ADVISORY FROM 1 AM TO 7 PM EST TUESDAY FOR MIZ039-
040-045-046-051-052-059-067-074.
LM...SMALL CRAFT ADVISORY UNTIL 7 PM EST WEDNESDAY FOR LMZ844>849.
&&
$$
SYNOPSIS...MJS
SHORT TERM...MJS
LONG TERM...TJT
AVIATION...TJT
HYDROLOGY...JAM
MARINE...TJT
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
329 PM EST MON JAN 11 2016
LATEST UPDATE...
SYNOPSIS/SHORT TERM/LONG TERM
.SYNOPSIS...
ISSUED AT 305 PM EST MON JAN 11 2016
A WAVE OF LOW PRESSURE WILL DEEPEN AS IT TRACKS EASTWARD THROUGH
LOWER MICHIGAN TONIGHT. SNOW WILL INCREASE ACROSS THE REGION AS A
RESULT AND COULD BE HEAVY. THE SNOW WILL PERSIST THROUGH TUESDAY
WITH LOCALLY HEAVY SNOW ESPECIALLY CLOSE TO LAKE MICHIGAN.
HAZARDOUS TRAVEL IS EXPECTED FOR MOST AREA THROUGH TUESDAY.
ARCTIC AIR WILL CONTINUE TO FLOW INTO THE REGION ON WEDNESDAY WITH
ADDITIONAL LAKE EFFECT SNOW POSSIBLE.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT)
ISSUED AT 305 PM EST MON JAN 11 2016
COMMONLY WITH A DIGGING SYNOPTIC WAVE FOLLOWED BY AN ARCTIC
AIRMASS WE TEND TO SEE WIDESPREAD IMPACTS...SOMETIMES SIGNIFICANT
IMPACTS. THUS I WENT WITH A WARNING FOR MUCH OF THE LAKESHORE
REGION AND A FEW INLAND COUNTIES AS WELL.
THE LOW LEVEL FLOW BACKS THIS EVENING AS THE WAVE APPROACHES. THIS
WILL ACT TO FOCUS THE MAIN BAND WEST OF KENT COUNTY DUE TO THE
FLOW BECOMING SOUTHEAST OVER GRAND RAPIDS THIS EVENING. AS A
RESULT IT APPEARS KENT COUNTY WILL MISS MUCH OF THIS INITIAL
BANDING THIS EVENING...SO I DID NOT INCLUDE KENT IN THE WARNING. SOME
NEWER MODELS ACTUALLY TAKE THE BANDING WEST OF MUSKEGON. THIS
WOULD BE UNUSUAL. THE FLOW VEERS NORTHWEST BY 12Z TUE. THE
TUESDAY MORNING COMMUTE LOOKS QUITE IMPACTED AS THE BANDS SHIFT
AND HEAVY SNOW SHOWERS PERSIST. ALSO THE WINDS WILL INCREASE LATE
TONIGHT ALONG THE LAKESHORE AND ALL LOCATIONS ON TUESDAY. BLOWING
SNOW WILL INCREASE. I NOTICED THE LATEST HRRR RUC HAD GREATER THAN
35 KNOTS ON THE LAKESHORE. THIS COMBINED WITH HEAVY SNOW BANDS
SHOULD SUPPORT NEAR WHITEOUT CONDITIONS.
I EXTENDED THE HEADLINES INLAND. THE STRONGER WINDS WILL ACT TO
CARRY THE SNOW SHOWERS WELL INLAND. THAT COMBINED WITH WIND GUSTS
OVER 20 KNOTS WILL SUPPORT HAZARDOUS TRAVEL AT TIMES ON TUESDAY.
.LONG TERM...(THURSDAY THROUGH MONDAY)
ISSUED AT 305 PM EST MON JAN 11 2016
MAIN CONCERN CONTINUES TO BE WINTER WEATHER FRIDAY NIGHT. MOST MODEL
GUIDANCE INDICATES LIMITED SNOWFALL WITH THIS EVENT DUE TO STRONG
LOW LEVEL WARM ADVECTION AHEAD OF THE SURFACE LOW. AS NOTED IN THE
PREVIOUS DISCUSSION...THE GFS HAS BEEN INCONSISTENT RUN TO RUN.
HOWEVER THE GFS PARALLEL...GEM...AND FIM ALL FAVOR A WARMER SOLUTION
MORE CONSISTENTLY.
AS NOTED ALREADY...THE DETERMINISTIC ECMWF SHOWS GOOD RUN TO RUN
CONSISTENCY WITH A LOW TRACK INTO THE OHIO VALLEY FAVORABLE FOR SNOW
OVER THE FORECAST AREA. HOWEVER...THIS CONTROL RUN IS AN OUTLIER
RELATIVE TO MOST ENSEMBLE MEMBERS THAT SHOW LOW TRACKS EITHER OVER
LOWER MICHIGAN OR MUCH FARTHER SOUTHEAST.
ALL THAT SAID...THERE ARE GOOD REASONS PUT FORTH IN THE PREVIOUS
DISCUSSION TO NOT DISCOUNT THE DETERMINISTIC ECMWF ENTIRELY AND TO
CONTINUE WATCHING THIS.
WHAT IS MORE CERTAIN IS SIGNIFICANT PRECIPITATION FALLING ON A
DECENT SNOWPACK BY THE END OF THE WEEK...RAISING CONCERNS FOR RIVERS
THAT ARE DISCUSSED IN DETAIL IN THE HYDROLOGY SECTION.
A FINAL CONCERN IS THE POTENTIAL FOR LIGHT FREEZING RAIN FRIDAY
MORNING AS DEEP MOISTURE OVERSPREADS SURFACE AIR TEMPERATURES IN THE
MID TO UPPER 20S. THIS COULD AFFECT THE FRIDAY MORNING COMMUTE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 104 PM EST MON JAN 11 2016
THROUGH 21Z...MAIN CONCERN IS A PERSISTENT EAST TO WEST SNOW BAND IMPACTING
PRIMARILY THE KGRR TERMINAL WITH IFR VSBY. THIS BAND SHOULD DRIFT
NORTH WITH GRADUALLY IMPROVING CONDITIONS AT THE GRR AND MKG TERMINALS.
BEGINNING AROUND 00Z...A RAPID REDUCTION TO IFR VSBY CAN BE
EXPECTED BY THE LAKESHORE AS AN INTENSE AREA OF SNOW DEVELOPS.
SNOW WILL SPREAD EASTWARD AS WINDS SHIFT TO THE WEST AND
STRENGTHEN. VISIBILITIES WILL BE HIGHLY VARIABLE ESPECIALLY
BETWEEN 00Z-10Z DUE TO PASSING SNOW BANDS.
EXPECT A TRANSITION TO MORE WIDESPREAD IFR OR FUEL ALTERNATE MVFR
VSBYS IS EXPECTED AFTER 12Z WITH BLOWING SNOW AN INCREASING
CONCERN...ESPECIALLY NEAR THE LAKESHORE.
&&
.MARINE...
ISSUED AT 324 AM EST MON JAN 11 2016
WAVE WILL DECREASE TO AROUND 2 TO 4 FEET THIS AFTERNOON. THE SMALL
CRAFT ADVISORY CONTINUES THROUGH THIS AFTERNOON. AFTER A LULL
TONIGHT WINDS WILL INCREASE TO 30 KNOTS AND ANOTHER SCA WILL LIKELY
BE NEEDED.
&&
.HYDROLOGY...
ISSUED AT 1121 AM EST MON JAN 11 2016
MINOR RIVER FLOODING IS ONGOING AT HOLT...MAPLE RAPIDS AND IONIA.
THE MAPLE RIVER AT MAPLE RAPIDS WILL CONTINUE TO GRADUALLY CLIMB
OVER THE NEXT COUPLE OF DAYS BEFORE STABILIZING. HOLT AND IONIA
HAVE BEGUN TO SHOW DECLINE. IMPROVEMENT SHOULD CONTINUE.
MANY OTHER SITES THROUGH SOUTHWEST LOWER MICHIGAN ARE FLOWING
WELL BELOW ACTION STAGE WHILE THE RISES AND HIGHER LEVELS ARE
CONCENTRATED SOUTH AND EAST OF GRAND RAPIDS. THESE ARE THE SAME
AREAS THAT WERE MORE SO AFFECTED BY MILD WEATHER AND RAINFALL
EARLY IN THE WEEKEND. GOING FORWARD...OVERALL STABILIZATION OR
IMPROVEMENT IS ANTICIPATED IN THE GRAND SCHEME OF THINGS. CONCERNS
ARE MINOR...WHICH INCLUDE THE ACTIVE WEATHER PATTERN AND ARCTIC
AIR MASS.
PRECIPITATION CHANCES EXIST AT SOME POINT EACH DAY OF THE WEEK.
THE GOOD NEWS IS THAT IT WILL ALL LIKELY BE IN THE FORM OF SNOW.
THE DOWN SIDE WITH THESE TEMPERATURES IS THE RISING CONCERN FOR
ICE FORMATION...ESPECIALLY IN CENTRAL LOWER MICHIGAN WHERE
TEMPERATURES HAVE BEEN COLDER FOR A LONGER PERIOD OF TIME. THIS
MAY BE THE WEEK WHERE WE SEE SOME ISSUES DEVELOP WITH MINOR ICE
JAMMING...ESPECIALLY ON LOWER VOLUME RIVERS THAT FREEZE UP IN A
QUICKER FASHION. IT IS NOTHING OF ALARM AT THIS POINT...BUT JUST
SOMETHING TO KEEP AN EYE ON WITH OVERNIGHT TEMPS IN THE SINGLE
DIGITS.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...WINTER STORM WARNING FROM 7 PM THIS EVENING TO 7 PM EST TUESDAY
FOR MIZ037-038-043-044-050-056-064-071-072.
WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 7 PM EST
TUESDAY FOR MIZ057-058-065-066-073.
WINTER WEATHER ADVISORY FROM 1 AM TO 7 PM EST TUESDAY FOR MIZ039-
040-045-046-051-052-059-067-074.
LM...SMALL CRAFT ADVISORY UNTIL 5 PM EST THIS AFTERNOON FOR
LMZ844>849.
&&
$$
SYNOPSIS...MJS
SHORT TERM...MJS
LONG TERM...TJT
AVIATION...TJT
HYDROLOGY...JAM
MARINE...TJT
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
300 PM CST MON JAN 11 2016
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 300 PM CST MON JAN 11 2016
LIGHT SNOW AT MID AFTERNOON PUSHING INTO CENTRAL MINNESOTA WILL
ADVANCE QUICKLY EAST-SOUTHEAST THROUGH THIS EVENING AS A WAVE OF
LOW PRESSURE MOVES ALONG THE ARCTIC FRONT. MUCH OF THE ACCUMULATING
SNOW (AROUND AN INCH) REMAINS FOCUSED ALONG AND NORTH OF I-94
WITH AMOUNTS DWINDLING TO A FEW TENTHS ONCE YOU REACH THE
MINNESOTA RIVER VALLEY.
A CONCERN GOING FORWARD THROUGH THE EVENING IS THE AMOUNT OF
BLOWING SNOW THAT WILL OCCUR ACROSS WEST CENTRAL MINNESOTA AS
STRONG PRESSURE RISES FOLLOW THE ARCTIC WAVE. RAP PROFILE DATA AT
KMOX IS A LITTLE DISCONCERTING. THE PROFILE THROUGH THE EVENING IS
SATURATED FROM THE SFC-700MB IN THE DENDRITIC GROWTH ZONE WHILE
THE WIND PROFILE SHOWS 25 KNOTS JUST OFF THE SURFACE WITH 33 KNOTS
AT THE TOP OF THE CHANNEL. OUR NEIGHBORS TO THE WEST WERE NOT TOO
CONCERNED DUE TO THE LACK OF SNOW ACCUMULATION EXPECTED BEFORE THE
STRONG WINDS ARRIVE. THEREFORE...NO ADVISORIES PLANNED AT THIS
TIME BUT THIS WILL NEED TO BE WATCHED. ON OUR END...INDICATED
AREAS OF BLOWING SNOW INTO THE EARLY MORNING HOURS OF TUESDAY.
KEPT LOWS TONIGHT AND HIGHS TUESDAY ON THE COLD SIDE BASED ON
RECENT VERIFICATION. THIS RESULTS IN ALL SITES BETWEEN 5 AND 10
DEGREES BELOW ZERO TONIGHT WITH HIGHS TUESDAY FROM ZERO TO 5
ABOVE. THE WIND CHILL ADVISORY ISSUED EARLIER TODAY FOR THE FA
LOOKS GREAT GIVEN THE EXPECTED TEMPERATURES AND WIND SPEEDS TONIGHT
AND EARLY TUESDAY.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 300 PM CST MON JAN 11 2016
THE BEST WAY TO SUM UP THE NEXT SEVERAL DAYS WOULD BE COLD WITH
OCCASIONAL SNOW SHOWERS. A FAIRLY SIGNIFICANT WINTER STORM WILL
DEVELOP ACROSS THE MIDWEST ON FRIDAY/SATURDAY...BUT AT THIS TIME IS
APPEARS THE MAJORITY OF THE ACCUMULATING SNOW WILL FALL SOUTHEAST OF
THE FORECAST AREA.
AT THE START OF THE PERIOD TUESDAY NIGHT NORTHWEST FLOW WILL BE IN
PLACE...WITH SLIGHT H850 WARM AIR ADVECTION. A NORTHWEST/SOUTHEAST
TEMPERATURE GRADIENT WILL LAY OUT ACROSS THE REGION...AND THIS WILL
BE THE FOCUS FOR A BAND OF LIGHT SNOW THAT WILL DEVELOP ON WEDNESDAY
MAINLY ALONG AND NORTH OF I-94.
THIS BAND OF SNOW WILL SLOWLY SHIFT EASTWARD THURSDAY NIGHT.
MEANWHILE AND UPPER LEVEL WAVE WILL MOVE FROM THE TEXAS PANHANDLE UP
TOWARDS THE OHIO RIVER VALLEY. AS IT DOES SO...A SURFACE LOW
PRESSURE SYSTEM WILL DEVELOP ACCOMPANIED BY A BAND OF HEAVY SNOW ON
THE COLD SIDE OF THE PRECIPITATION SHIELD. THERE IS STILL A
CONSIDERABLE AMOUNT OF UNCERTAINTY WITH THIS SYSTEM SINCE THE EXACT
TRACK DEPENDS ON THE INTERACTION OF BOTH THE NORTHERN AND SOUTHERN
JET STREAMS. FOR THIS REASON...DID NOT INCREASE POPS ABOVE THE
BLENDED MODEL GUIDANCE. IT STILL LOOKS LIKE THE BEST CHANCE FOR A
FEW INCHES OF ACCUMULATING SNOW WOULD BE FROM ALBERT LEA UP THROUGH
EAU CLAIRE WI. LOOKING AHEAD...ANOTHER BLAST OF ARCTIC AIR WILL
ARRIVE IN THE WAKE OF THIS STORM...WITH TEMPERATURES FALLING BACK
BELOW ZERO EARLY NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1143 AM CST MON JAN 11 2016
MVFR CIGS AND IFR VSBYS IN -SN OVER EASTERN ND...ASSOCIATED WITH A
CLIPPER LOW PRESSURE SYSTEM...WILL MARCH SOUTHEAST THIS AFTERNOON
AND EARLY EVENING ACROSS THE TAF SITES. CLEARING WILL OCCUR RATHER
QUICKLY IN THE WAKE OF THE LOW. SOUTHERLY WINDS THIS AFTERNOONAHEAD
OF THE LOW FROM 5 TO 10 KNOTS WILL SHIFT NW WITH THE PASSAGE OF
THE LOW. WIND SPEEDS WILL INCREASE TO 15 KNOTS OR SO WITH GUSTS
INTO THE MID 20 KNOT RANGE.
KMSP...LESS THAN VFR CONDITIONS WITH -SN REMAIN ON TRACK TO REACH
THE AIRFIELD BY 22Z AND PERSIST INTO THE EARLY EVENING. UP TO AN
INCH OF ACCUMULATION LIKELY. NW WINDS WILL BE ON THE INCREASE
AFTER 03Z WITH SPEEDS NEAR 15 KNOTS WITH GUSTS 20-25 KNOTS. WINDS
WILL DIMINISH SOME BY DAYBREAK TUESDAY.
/OUTLOOK FOR KMSP/
WED...VFR. WINDS SW 5-10 KTS.
THU...VFR. WINDS SE 5-10 KTS.
FRI...VFR. MVFR/-SN POSSIBLE. WINDS N 5-10 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
WI...WIND CHILL ADVISORY FROM 3 AM TO NOON CST TUESDAY FOR WIZ014>016-
023>028.
MN...WIND CHILL ADVISORY FROM 3 AM TO NOON CST TUESDAY FOR MNZ053-
060>063-067>070-073>078-082>085-091>093.
WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO NOON CST TUESDAY
FOR MNZ041>045-047>052-054>059-064>066.
&&
$$
SHORT TERM...RAH
LONG TERM...JRB
AVIATION...RAH
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1236 PM EST MON JAN 11 2016
.SYNOPSIS...
A WESTERLY FLOW OF COLD AND MOIST AIR WILL BRING SCATTERED SNOW
SHOWERS AND FLURRIES TO A LARGE PART OF CENTRAL NEW YORK AND
NORTHEAST PENNSYLVANIA TODAY. A LOW PRESSURE SYSTEM WILL TRACK
ACROSS THE GREAT LAKES TONIGHT TO OFF THE NEW ENGLAND COAST BY
TUESDAY NIGHT. THIS SYSTEM WILL BRING A WIDESPREAD INCH OR TWO OF
SNOW TO THE REGION TUESDAY. AFTER THIS SYSTEM PASSES BY, HEAVY
LAKE EFFECT SNOW WILL BE POSSIBLE ALONG THE THRUWAY CORRIDOR FROM
SYRACUSE TO UTICA AND ROME TUESDAY NIGHT AND WEDNESDAY. ELSEWHERE
EXPECT SCATTERED SNOW SHOWERS AND FLURRIES WITH ONLY LIGHT
ACCUMULATIONS THROUGH WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
DROPPED WIND ADVISORY AS WINDS WILL CONTINUE TO WEAKEN. SYR STILL
GUSTING WITH A PEAK WIND AT 519 AM OF 44 KNOTS. REST OF STATIONS
AROUND NORTH CENTRAL NY HAVE SEEN WINDS WEAKEN CONSIDERABLY WITH
PEAK WINDS BARELY 30 KNOTS. MADE SOME MINOR ADJUSTMENTS TO POPS
ESPECIALLY FOR WESTERN STEUBEN CO WHERE I COULD SEE A FEW INCHES
OF SNOW TODAY. OTHERWISE NO MAJOR CHANGES TO PREVIOUS FORECAST.
PREVIOUS DISCUSSION BELOW...
RADAR IMAGERY SHOWS MAIN LAKE EFFECT SNOW BAND NORTH OF ONEIDA
COUNTY. THE KTYX VAD WIND PROFILE IS SHOWING A 260 DEGREE FLOW
FROM 3 TO 8 THOUSAND FEET ABOVE SEA LEVEL AND WAS DIRECTING THE
LAKE EFFECT SNOWS TO OUR NORTH. THE 00Z RGEM, 00Z NAM12,
WRF_ARW,AND HRRR WERE ALL KEEPING THIS BAND TO OUR NORTH THROUGH
THE DAY. THE ONLY HI RES MODEL THAT WAS BRINGING THE BAND INTO
NORTHERN ONEIDA COUNTY TODAY WAS THE WRF_NMM. THE MODELS HAVE
TRENDED NORTH WITH THE BAND FROM YESTERDAY AND CURRENT RADAR
INDICATES THAT THIS WILL BE THE CASE SO WILL KEEP SIGNIFICANT
SNOWS OUT OF OUR FORECAST AREA TODAY. LAKE EFFECT SNOW WARNINGS
ARE OUT TO OUR NORTH AND LOOK GREAT. THE REST OF THE FORECAST AREA
WAS SEEING SCATTERED SNOW SHOWERS AND FLURRIES ON A WEST TO
SOUTHWEST FLOW. NAM AND GFS SOUNDINGS ARE SHOWING VERY STEEP LOW-
LEVEL LAPSE RATES THRU THE MORNING WHICH WAS LEADING TO SOME
SMALL CAPE UNDER THE INVERSION WHICH WAS AT ABOUT 800 MB OR 5000
FEET. THIS WAS ENOUGH TO ORGANIZE SOME SNOW SHOWERS AND FLURRIES.
MUCH OF THIS SMALL CAPE WAS IN THE MAX GROWTH REGIME FOR ICE
CRYSTALS. AS THE DAY PROGRESSES THE BOUNDARY LAYER WILL CONTINUE
TO BE DRYING AND I EXPECT THE ACVTY TO MOVE BACK CLOSER TO THE
LAKES. SO I HAVE SCATTERED SNOW SHOWERS AND FLURRIES DIMINISHING
SOME TO THE WEST.
AS FOR WINDS SYR JUST GUSTED TO 40 KNOTS AND RME WAS STILL HITTING 38
KNOTS WHICH IS CLOSE TO ADVY CRITERIA. WILL HOLD ONTO WIND ADVY
UNTIL WINDS MARKEDLY DROP OFF.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
FOR TONIGHT AND TUESDAY...ALL MODELS SHOW A CLIPPER-TYPE SYSTEM
TRACK FROM THE GREAT LAKES REGION TONIGHT TO NORTH OF LAKE
ONTARIO BY TUESDAY EVENING AND THEN TO OFF THE NEW ENGLAND COAST
BY WEDNESDAY MORNING. AS THIS SYSTEM APPROACHES NEW YORK AND
PENNSYLVANIA THE LOW-LEVEL WINDS WILL BACK TO THE SOUTHWEST AND
SEND ANY RESIDUAL LAKE EFFECT SNOW SHOWERS TO THE NORTH OR CUT
THEM OFF FROM THEIR SOURCE REGION. SO I DRY OUT TONIGHT IN OUR
FORECAST. ALL SYNOPTIC SCALE MODELS SHOW A REGION OF WARM AIR
ADVECTION (OR ISENTROPIC LIFT IF YOU PREFER THAT COORDINATE
SYSTEM) ACROSS NEW YORK AND PENNSYLVANIA TUESDAY MORNING. HOWEVER
THIS SYSTEM WILL BE MOISTURE STARVED AND SOUTHWEST WINDS TEND TO
DOWNSLOPE ACROSS A WIDE AREA OF CENTRAL NY AND NORTHEAST PA. THE
EXCEPTIONS ARE THE CATSKILLS AND SOUTHERN TUG HILL PLATEAU AND
ALLEGHENIES OF WESTERN NY. THEN AS THE CLIPPER TRACKS TO OUR
NORTHEAST TUESDAY AFTERNOON THERE IS SOME LAKE ENHANCED COLD FRONTAL
SNOW SHOWERS THAT WILL ADD A BIT MORE TO THE TOTAL ACCUMULATIONS.
FOR NOW WE SEE MOST AREAS GETTING AROUND 1 INCH WITH LOCALLY 2-3
INCHES IN THE CATSKILLS TO UPPER MOHAWK AND SOUTHERN TUG HILL
PLATEAU AND WESTERN STEUBEN COUNTY.
AFTER THIS SYSTEM PASSES TUESDAY EVENING, THE INVERSION CLIMBS TO
ALMOST 700 MB AND THE MEAN WIND IN THIS LAYER IS FROM 280-290
DEGREES. BOTH THE GFS AND NAM MODEL SOUNDINGS BETWEEN ABOUT 6Z-9Z
AND 18Z-21Z WEDNESDAY INDICATE UPWARD MOTION IN THE MAX ICE
CRYSTAL GROWTH REGIME SUGGESTING SIGNIFICANT SNOW GROWTH
POTENTIAL. THE 850 MB TEMPERATURES WERE AROUND -18C WHICH GIVES AT
LEAST A 23C DIFFERENTIAL WHICH IS EXTREME LAKE-INDUCED
INSTABILITY. THE ONLY UNCERTAINTY IS THE EXACT WIND DIRECTION
WHICH IS STILL SOMEWHAT UNCERTAIN. IT LOOKS LIKE AT LEAST 8-12
INCHES OF SNOW TUESDAY NGT AND WEDNESDAY AND POSSIBLY MORE
SOMEWHERE IN ONONDAGA, MADISON OR ONEIDA COUNTIES. THIS COULD BE A
BIG EVENT FOR THE THRUWAY CORRIDOR, THE FIRST OF THIS LATE
EVOLVING WINTER SEASON. ISSUED LAKE EFFECT SNOW WATCHES FOR
TUESDAY NIGHT AND WEDNESDAY TO COVER FOR ONONDAGA, ONEIDA AND
MADISON COUNTIES.
ALL LAKE EFFECT ACTIVITY WINDS DOWN WED NGT AS FLOW BACKS MORE
SOUTHWESTERLY.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
WIND FIELD WILL LIKELY WAVER BACK AND FORTH BETWEEN NW AND WEST
THROUGH THURSDAY AND FRIDAY...BUT WITH ENOUGH OF A CONTINUOUS
INFLUX OF COLD AIR TO KEEP THE LAKE BANDS GOING. AT THIS TIME IT
APPEARS THE WED THROUGH THURSDAY NIGHT TIME PERIOD APPEARS TO BE
THE MOST FAVORABLE FOR SIGNIFICANT LAKE EFFECT SNOW ACCUMULATIONS
ACROSS THE NRN COUNTIES. WILL NEED TO KEEP AN EYE ON THIS EVENT AS
IT DEVELOPS THROUGH THE WEEK AND MODEL GUIDANCE GETS A BETTER
HANDLE ON THE WIND TRAJECTORIES.
A WEAK RIDGE OF HIGH PRESSURE EVENTUALLY BUILDS IN FROM THE NORTH
ON FRIDAY AND ALLOWS THE LES TO END. THE PATTERN IS EXPECTED TO
REMAIN ACTIVE HOWEVER INTO THE WEEKEND AS ANOTHER STORM SYSTEM IS
FORECAST TO DEVELOP OVER THE OHIO VALLEY AND LIFT INTO THE NE
THROUGH THE WEEKEND. IT IS TOO EARLY TO DETERMINE THE EXACT NATURE
OF THIS SYSTEM...BUT ALL SIGNS POINT TO A WINTRY STORM SYSTEM.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
MAINLY VFR CONDITIONS THROUGH THE PERIOD...WITH TWO ISSUES OF
CONCERN. ONE...THE WINDS WILL BE VERY GUSTY FROM THE WEST THROUGH
23Z OR 12/00Z ACROSS THE REGION WITH CIGS RUNNING AROUND 3 TO
5KFT. THE WINDS WILL DECREASE AND SLOWLY TURN TO THE SOUTH
OVERNIGHT WITH LESS CLOUDS ACROSS THE REGION AS A WHOLE. THE
SECOND ISSUE WILL BE THE LOWER CIGS AGAIN VERY LATE IN THE
PERIOD...POSSIBLY MVFR WITH DROP TO AROUND 2 TO 2.5K FT. ALSO AS
THE CIGS LOWER SOME LIGHT SNOW WILL DEVELOP...ESPECIALLY OVER THE
NORTHERN PORTIONS OF CNY...WITH VSBY RESTRICTED POSSIBLY TO 2 OR
3SM AT KSYR AND KRME AFTER 12Z.
.OUTLOOK...
TUE...CLIPPER SYSTEM WILL PASS WITH WINDOW OF WIDESPREAD -SN AND
MVFR-IFR RESTRICTIONS...MAINLY DURING THE AFTERNOON INTO EVENING.
TUE NGT-WED...LAKE SHSN MAINLY NY TERMINALS. VERY RESTRICTIVE
CONDITIONS POSSIBLE AT TIMES LATE TUE NGT INTO WED FOR KSYR-KRME
IF HEAVIER LAKE ONTARIO BANDS MANAGE TO PASS OVER TERMINALS.
WED NGT-THU-THU NGT...LAKE EFFECT SHSN AND ASSOCIATED
INTERMITTENT RESTRICTIONS MAINLY NY TERMINALS.
FRI...MAINLY VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...LAKE EFFECT SNOW WATCH FROM TUESDAY EVENING THROUGH WEDNESDAY
EVENING FOR NYZ009-018-036-037.
&&
$$
SYNOPSIS...DJN
NEAR TERM...DJN
SHORT TERM...DJN
LONG TERM...BJT/MDP
AVIATION...ABS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1218 PM CST MON JAN 11 2016
.UPDATE...
ISSUED AT 1218 PM CST MON JAN 11 2016
NO SIGNIFICANT CHANGES WITH THIS UPDATE...AND NO CHANGE TO THE
WINTER WEATHER ADVISORY FOR FAR SOUTHWEST ND. THE BATCH OF LIGHT
SNOW THAT AFFECTED CENTRAL ND IS EXITING STAGE RIGHT AT MIDDAY AND
IS LEAVING FLURRIES AND INCREASING NORTHWEST WINDS IN ITS WAKE AS
THE SURFACE LOW NEAR DEVILS LAKE AT 18 UTC SHIFTS SOUTHEAST. RADAR
HAS SHOWN SNOW DEVELOPING OVER EASTERN MT THE LAST FEW HOURS...AND
RECENT RAP/HRRR SIMULATIONS STILL TAKE IT INTO SOUTHWEST ND DURING
THE AFTERNOON WITH LIQUID-EQUIVALENT TOTALS OF 0.10 TO 0.20 INCHES
/WHICH SHOULD BE GOOD FOR 1-2 INCHES OF SNOW/.
UPDATE ISSUED AT 840 AM CST MON JAN 11 2016
QUICK UPDATE TO INCREASE POPS TO THE CATEGORICAL /80-100 PERCENT/
RANGE OVER NORTH CENTRAL ND FROM MINOT TO ROLLA AND RUGBY THROUGH
LATE MORNING. RADAR IMAGERY AND SURFACE OBSERVATIONS SHOW THAT
LIGHT SNOW HAS QUICKLY INCREASED IN THAT AREA SINCE 1430 UTC.
OTHERWISE...NO SIGNIFICANT CHANGES TO THE REST OF THE FORECAST.
THE NEW 12 UTC NAM IS CONSISTENT WITH THE SNOW AND BLOWING SNOW
HAZARD THAT WILL DEVELOP ACROSS SOUTHWEST ND BY THIS AFTERNOON. NO
CHANGES NEEDED TO THE WINTER WEATHER ADVISORY AT THIS TIME.
UPDATE ISSUED AT 710 AM CST MON JAN 11 2016
GIVEN CONSISTENT TRENDS IN THE 08 THROUGH 11 UTC RAP AND HRRR
ITERATIONS...BUMPED UP THE START TIME FOR THE WINTER WEATHER
ADVISORY ACROSS THE FAR SOUTHWEST TO 17 UTC TO BETTER CAPTURE THE
ONSET OF SNOWFALL. THE RAP AND HRRR HAVE CONSISTENTLY HAD A
STRONGER WIND FIELD AND MORE SNOWFALL WHEN COMPARED TO THE GLOBAL
MODELS. AS OF LATE...THE RAP AND HRRR HAVE PERFORMED
WELL..ESPECIALLY REGARDING MESOSCALE SNOWFALL EVENTS. THE
CHALLENGE FOR TODAY IS IF THE ADVISORY FOR BLOWING SNOW MAY NEED
TO BE EXPANDED FURTHER EAST TO ALONG THE MISSOURI RIVER...WHERE
THE RAP AND HRRR SUGGEST AND INCH OR SO OF FRESH SNOW MAY BE
POSSIBLE.
UPDATE ISSUED AT 515 AM CST MON JAN 11 2016
WITH CONTINUED SUPPORT FROM THE HRRR/RAP13...AND NOW THE 4KM NAM
FOR WINDS OF 25KT TO 35KT IN THE MIXED LAYER ACROSS THE FAR
SOUTHWEST...WILL BE ISSUING A WINTER WEATHER ADVISORY FOR SNOW AND
BLOWING SNOW FROM 19Z MONDAY TO 02Z TUESDAY. STILL EXPECTING ONE
TO TWO INCHES WITH GUSTY WINDS COINCIDING WITH THE FALLING SNOW. THIS
INCLUDES GOLDEN VALLEY...BILLINGS...SLOPE...AND BOWMAN COUNTIES.
UPDATES FORTHCOMING.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 315 AM CST MON JAN 11 2016
HIGHLIGHTS IN THE SHORT TERM INCLUDE PATCHY BLOWING SNOW ALONG
WITH ISOLATED TO SCATTERED SNOW SHOWERS REDUCING VISIBILITIES
MONDAY AFTERNOON/EVENING. THE HIGHEST CONCERN IS THE FAR SOUTHWEST
WHERE 1 TO 2 INCHES OF SNOW THIS AFTERNOON COMBINED WITH GUSTY
WINDS PUTS THIS AREA AT GREATEST RISK FOR A POSSIBLE WINTER
WEATHER ADVISORY FOR BLOWING SNOW WITH VISIBILITIES AROUND ONE
HALF MILE. FOR NOW WE HAVE DECIDED TO MONITOR THE HRRR AND RAP13
BUFKIT SOUNDINGS TO SEE IF CURRENT TRENDS OF STRONGER WINDS
CONTINUE OVER THE NEXT SEVERAL HOURS. THAT ALLOWS SUFFICIENT TIME
IN THE NEXT ONE TO TWO UPDATE CYCLES TO ISSUE SOMETHING IF THE
SITUATION WARRANTS. OTHERWISE...WIND CHILL TEMPERATURES 25 TO 30
BELOW ZERO EXPECTED LATE MONDAY NIGHT NORTH CENTRAL AND INTO THE
NORTHERN JAMES RIVER VALLEY THROUGH TUESDAY MORNING. AFTER
COLLABORATING WITH NEIGHBORING OFFICES WILL AGAIN LET THE DAYSHIFT
HONE IN ON THE COUNTIES AFTER ANOTHER MODEL CYCLE COMES IN THIS
MORNING AND AFTERNOON.
THE LATEST WATER VAPOR IMAGERY SHOWS THIS NEXT SHORTWAVE THROUGH
NOW STREAMING THROUGH NORTHWEST SASKATCHEWAN AND DIVING SOUTHEAST
WITH TIME. ACCOMPANYING THE SHORTWAVE IS A 300MB 140KT JET STREAK.
WITH THE JET AND SHORTWAVE MAINTAINING A SOUTHEAST MOVEMENT THROUGH
00Z TUESDAY...THE FAVORED LEFT EXIT REGION OF THE JET FOR LARGE
SCALE ASCENT REMAINS JUST OFF TO OUR EAST. HENCE PRECIPITATION
AMOUNTS WILL REMAIN LIGHT AND THIS LIMITS SIGNIFICANT REDUCTIONS
IN VISIBILITIES. THE EXCEPTION WILL BE ACROSS THE HIGHER TERRAIN
IN THE FAR SOUTHWEST CLOSEST TO THE BAROCLINIC ZONE AND STRONGER
OMEGA/VERTICAL MOTION...FAVORING HIGHER AMOUNTS OF SNOWFALL.
ASSOCIATED WITH THE SHORTWAVE MENTIONED ABOVE IS AN ARCTIC FRONT
IN SOUTHERN ALBERTA/SASKATCHEWAN/MANITOBA...WHICH WILL SWEEP DOWN
ACROSS WESTERN AND CENTRAL NORTH DAKOTA TODAY. GUSTY NORTHWEST
WINDS BETWEEN 20 AND 35 MPH WILL DEVELOP IN ITS WAKE THIS AFTERNOON
AND INTO THE EARLY EVENING. THE STRONGEST WINDS FORECAST ACROSS
THE NORTH CENTRAL AND JAMES RIVER VALLEY WHICH FOLLOWS THE LOCATION
AND TRAJECTORY OF THE 6HR PRESSURE RISES AND UPPER JET MENTIONED
ABOVE. THE BAGGALEY BLOWING SNOW INDICATING THAT ONLY A VERY SMALL
AREA ACROSS THE NORTH CENTRAL WOULD BE IN LINE FOR A VERY LOW END
WINTER WEATHER ADVISORY FOR BLOWING SNOW...IF ONLY BLOWING SNOW
OCCURRED. ADDING A MENTION OF SNOWSHOWERS INTO THE FORMULA WITH A
WORST CASE SCENARIO OF AN INCH OF SNOW...A MORE WIDESPREAD LOW END
ADVISORY SHOWS UP. HOWEVER EXPECTATIONS ARE THAT SNOWFALL AMOUNTS
WILL REMAIN WELL UNDER ONE INCH...WITH THE EXCEPTION OF THE FAR
SOUTHWEST AS MENTIONED ABOVE. THUS WE HAVE DECIDED TO CONTINUE
WITH THE SPECIAL WEATHER STATEMENT ADVERTISING DRIFTING SNOW AND
PATCHY BLOWING SNOW REDUCING VISIBILITIES MAINLY IN OPEN COUNTRY.
MONDAY EVENING THE SURFACE WINDS WILL BEGIN DIMINISHING AS BOUNDARY
LAYER WINDS WEAKEN TO AROUND 20KT BY 06Z TUESDAY. SURFACE HIGH
PRESSURE MOVES FROM NEAR PLENTYWOOD MONTANA 06Z TUESDAY SOUTHEAST
INTO SOUTH CENTRAL SOUTH DAKOTA 12Z TUESDAY.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 315 AM CST MON JAN 11 2016
DANGEROUS WIND CHILLS TUESDAY MORNING...A POSSIBLE WARM UP INTO
THURSDAY...FOLLOWED BY ANOTHER POTENTIAL ARCTIC AIRMASS FOR FRIDAY
INTO THE WEEKEND HIGHLIGHT THE EXTENDED FORECAST.
DANGEROUS WIND CHILLS TO 30 BELOW ARE POSSIBLE ACROSS PORTIONS OF
CENTRAL NORTH DAKOTA TUESDAY MORNING IN ASSOCIATION WITH THE
ARCTIC AIRMASS ARRIVING MONDAY. THE WESTERN FRINGE OF THIS ARCTIC
AIRMASS IS FORECAST BY THE 00 UTC DETERMINISTIC AND ENSEMBLE
SUITES TO PROPAGATE EAST WEDNESDAY AND THURSDAY. THE RESULT IS A
POTENTIAL WARM UP WITH HIGHS WEDNESDAY AND THURSDAY IN THE UPPER
20S TO LOWER 30S ALONG AND WEST OF THE MISSOURI RIVER.
HOWEVER...AS HAS BEEN THE TREND OVER THE PAST COUPLE
DAYS...ANOTHER ARCTIC AIRMASS IS FORECAST TO POSSIBLY OVERTAKE THE
NORTHERN PLAINS FRIDAY INTO THE WEEKEND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1218 PM CST MON JAN 11 2016
MVFR AND IFR CONDITIONS ARE LIKELY THROUGH THE AFTERNOON ACROSS
MOST OF WESTERN AND CENTRAL ND DUE TO LOW CEILINGS AND IN MANY
CASES LIGHT SNOW AND SOME BLOWING/DRIFTING SNOW. CONDITIONS WILL
BE WORST ACROSS FAR SOUTHWESTERN ND WHERE SNOWFALL INTENSITY IS
FORECAST TO BE GREATEST. WINDS AND THE PROBABILITY OF SNOW WILL
BOTH DIMINISH THIS EVENING...BUT MVFR CEILINGS WILL LIKELY LINGER
INTO TUESDAY IN MANY AREAS BASED ON UPSTREAM TRENDS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 7 PM MST THIS EVENING FOR NDZ031-
032-040-043.
&&
$$
UPDATE...CJS
SHORT TERM...KS
LONG TERM...AYD
AVIATION...CJS
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
1144 AM CST MON JAN 11 2016
.AVIATION...
EXPECTING VFR CATEGORY CIGS THIS AFTERNOON AND EVENING AND
EVENING. WINDS WILL BE LIGHT AND EVENTUALLY SETTLE IN TO A
SOUTHEASTERLY DIRECTION.
&&
.PREV DISCUSSION... /ISSUED 834 AM CST MON JAN 11 2016/
UPDATE...
WE HAVE UPDATED THE FORECAST TO REMOVE THE WORDING FOR THE NOW
EXPIRED FREEZE WARNING. OTHERWISE...MINOR CHANGES HAVE BEEN MADE
TO THE HOURLY TEMPERATURES...DEW POINTS AND WINDS TO ACCOUNT FOR
RECENT OBSERVATIONS.
PREV DISCUSSION... /ISSUED 310 AM CST MON JAN 11 2016/
SHORT TERM (TODAY THROUGH TUESDAY)...
MAIN HEADLINE IN THE SHORT TERM WILL BE THE ISOLATED POCKETS OF
FREEZING TEMPERATURES ACROSS THE HIGHER ELEVATIONS OF BEXAR AND INTO
PORTIONS OF COASTAL PLAINS WHERE LESS CLOUDS RESIDE. OUTSIDE OF THIS
MARGINAL HAZARD - EXPECT VERY LOW END RAIN CHANCES FOR THE FAR
SOUTHEAST COASTAL PLAINS THIS EVENING INTO EARLY TUESDAY MORNING.
MOST LOCATIONS WILL NOT SEE ANY RAIN WITH PARTLY TO MOSTLY CLOUDY
SKIES TODAY.
SYNOPTIC PATTERN VIA WATER VAPOR CHANNELS AND RAP ANALYSIS DEPICTS
SPLIT FLOW BEGINNING TO DEVELOP AS THE SOUTHERN JET-STREAM BRANCH
BECOMES MORE ACTIVE. A HIGHLY POSITIVELY-TILTED SHORTWAVE TROUGH IS
OVER NEW MEXICO AND THIS, ALONG WITH WEAK MID-LEVEL DIVERGENCE, IS
ALLOWING FOR ELEVATED ECHOS TO APPEAR ON RADAR. THIS PRECIPITATION
IS NOT REACHING THE GROUND BUT THE RESULTANT CLOUDS ARE KEEPING
TEMPERATURES FROM BOTTOMING TO THEIR FULL POTENTIAL. BOERNE IS
CURRENTLY JUST BELOW THE FREEZING MARK AND COASTAL PLAIN
LOCATIONS WITHIN THE FREEZE WARNING ARE UNDER CLEAR SKIES AND
HEADING THAT DIRECTION. THE FREEZE WARNING IS IN EFFECT FROM 4AM
THROUGH 8AM AND TEMPERATURES ARE NOT EXPECTED TO BE AT FREEZING
FOR VERY LONG.
HAVE DELAYED THE ONSET OF ANY LIGHT RAIN/DRIZZLE UNTIL THIS EVENING
ACROSS THE FAR SOUTHEAST COASTAL PLAINS. OVERALL AVAILABLE MOISTURE
APPEARS TO BE MORE MEAGER THAN EVEN THE ALREADY LOW VALUES
ADVERTISED YESTERDAY. A WEAK BOUNDARY/PACIFIC FRONT WILL PUSH
THROUGH TUESDAY MORNING BRINING DRIER AIR IN THE SFC-700MB LAYER.
AMPLE SUN IS EXPECTED TUESDAY AFTERNOON AND A NICE WARM UP IS
EXPECTED INTO THE LOW 60S.
LONG TERM (WEDNESDAY THROUGH NEXT SUNDAY)...
DESPITE AN ACTIVE SOUTHERN JET-STREAM BRANCH AND SEVERAL PACIFIC
FRONTS EXPECTED TO MOVE THROUGH THE REGION THIS PERIOD...OVERALL
RAIN AMOUNTS REMAIN LOW. NO SIGNIFICANT HAZARDS APPEAR TO BE ON TAP
AT THIS POINT GIVEN THE MIS-ALIGNING OF LIMITED MOISTURE POOLING AND
DEEPER FORCING MECHANISMS. A GRADUAL WARM UP IS ANTICIPATED INTO THE
MID AND EVEN UPPER 60S BY THE END OF THE WEEK.
GLOBAL MODELS REMAIN AT ODDS WITH EACH OTHER CONCERNING THE
DIFFICULT PROGNOSTICATION OF THE SPLIT JET-STREAM FLOW. HAVE
FOLLOWED MORE OF A 33/33/33 WEIGHTED FORECAST WITH THE GFS/EC/GEM
THIS PACKAGE AS THE EC/GEM TEND TO HAVE MORE SUPPORT FROM THE NAM
AND UKMET MODELS IN MEDIUM AND LONG RANGE.
BY MID WEEK...ENERGY FROM THE CURRENT SHORTWAVE TROUGH WILL GET
TRAPPED/CUT-OFF OVER MEXICO AND IT WILL BE THIS COMPLEX THAT WILL
GIVE LIFT TO THE LIMITED MOISTURE IN PLACE LATE WEDNESDAY INTO
THURSDAY. GFS IS QUICKER AS IT PHASES SOME NORTHERN STREAM ENERGY IN
BUT EC/GEM/NAM ARE SLOWER. HAVE LEANED SLOWER AND PLACED 20-40% RAIN
CHANCES FROM WEST TO EAST FROM THE 35 CORRIDOR TO THE COASTAL
PLAINS. BEST TIME-FRAME FOR RAIN WILL BEGIN LATE WEDNESDAY NIGHT
THROUGH THURSDAY AFTERNOON. WESTERN AREAS STILL APPEAR TOO DRY FOR
ANY ACCUMULATING RAINFALL. A PACIFIC FRONT WILL PUSH THROUGH THE
REGION BY EARLY FRIDAY AND END RAIN CHANCES AS THE AFOREMENTIONED CUT-
OFF ENERGY PHASES WITH A STRONGER PASSING NORTHERN STREAM TROUGH.
WITH THE BRISK H5 FLOW, THE NEXT TROUGH APPROACHES THE REGION BY
SATURDAY. PWATS WILL BE 0.3-0.4" AND IT WILL BE DIFFICULT TO HAVE
PRECIPITATION REACH THE GROUND. HAVE OPTED FOR A DRY FORECAST FOR
NOW BUT CLOUDS WILL CERTAINLY BE ON THE INCREASE SATURDAY. BY
SUNDAY...THE TROUGH WILL SHIFT EAST AND USHER IN A POSSIBLE HYBRID
PACIFIC/BACKDOOR FRONT FROM THE NORTH. THIS SHOULD KEEP US DRY
SUNDAY BUT YET ANOTHER SYSTEM WILL BE ON ITS HEELS THAT APPEARS
STRONGER AND A BETTER CHANCE OF RAIN APPEARS POSSIBLE NEXT TUESDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 53 37 63 40 62 / 10 - 0 0 10
AUSTIN BERGSTROM INTL AIRPORT 53 34 62 36 61 / 10 - 0 0 10
NEW BRAUNFELS MUNI AIRPORT 54 35 63 39 61 / 10 - 0 - 10
BURNET MUNI AIRPORT 51 34 61 37 60 / 10 0 0 0 -
DEL RIO INTL AIRPORT 55 36 62 40 61 / - 0 0 0 0
GEORGETOWN MUNI AIRPORT 52 34 61 37 60 / 10 - 0 0 10
HONDO MUNI AIRPORT 54 34 62 39 60 / 10 - 0 - 10
SAN MARCOS MUNI AIRPORT 54 36 62 38 60 / 10 - 0 - 10
LA GRANGE - FAYETTE REGIONAL 55 38 62 40 62 / 10 10 0 - 10
SAN ANTONIO INTL AIRPORT 54 37 63 40 61 / 10 - 0 - 10
STINSON MUNI AIRPORT 55 38 63 41 61 / 10 - 0 - 10
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...05
SYNOPTIC/GRIDS...24
PUBLIC SERVICE/DATA COLLECTION...33