Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 01/13/16
AREA FORECAST DISCUSSION
NWS ALBANY NY
622 PM EST TUE JAN 12 2016
.SYNOPSIS...
A STRONG COLD FRONT WILL CROSS THE REGION THIS EVENING PRODUCING
SNOW SQUALLS. STRONG WINDS FOLLOWING THE SQUALL WILL FUNNEL COLD
AIR INTO OUR AREA. THE STRONG WINDS WILL PERSIST INTO WEDNESDAY
WITH LAKE EFFECT SNOW ACROSS THE WESTERN MOHAWK VALLEY.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
JUST MINOR ADJUSTMENTS TO THE FORECAST BASED ON THE EXIT OF THE
LIGHT SNOW EXITING WESTERN NEW ENGLAND AND THE TIMING OF THE LINE
OF SNOW SQUALLS ABOUT TO ENTER THE SOUTHERN ADIRONDACKS AND
WESTERN MOHAWK VALLEY...THAT SHOULD TRACK THROUGH THE FORECAST
AREA THROUGH THIS EVENING.
PREVIOUS AFD HAS MORE DETAILS AND IS BELOW...
MAIN FEATURE TONIGHT WILL BE COLD FRONTAL PASSAGE AND ASSOCIATED
SQUALL LINE. SOME LIGHTNING HAS BEEN OBSERVED WITH THIS SYSTEM AS
IT HAS MOVED ACROSS WESTERN AND CENTRAL NEW YORK. TIMING THE FRONT
VIA HRRR SIMULATED RADAR PUTS THE FRONT TO THE WESTERN MOHAWK
VALLEY BY AROUND 6PM...CAPITAL DISTRICT BY 8PM AND TO WESTERN NEW
ENGLAND BY ABOUT 9PM. THE SQUALL WILL FEATURE STRONG
WINDS...HEAVY AND BLOWING SNOW WITH VISIBILITIES NEAR ZERO.
ALTHOUGH SHORT-LIVED...SAY ABOUT 20 MINUTES IN ANY ONE
LOCATION...NEAR BLIZZARD CONDITIONS WILL PREVAIL FOR THE BRIEF
PERIOD OF SQUALL PASSAGE. TIMING OF THE SQUALL VIA THE HRRR RADAR
REFLECTIVITY HAS BEEN INCORPORATED INTO THE HOURLY GRIDS. IN
ADDITION...SPECIAL WEATHER STATEMENTS WILL BE USED TO TRACK THE
TRANSIT OF THE SQUALL ACROSS THE AREA. SNOWFALL FROM THE SQUALL
WILL BE NO MORE THAN AN INCH.
A WINTER WEATHER ADVISORY REMAINS IN EFFECT FOR THE SOUTHERN
ADIRONDACKS AND SOUTHERN GREEN MOUNTAINS THROUGH 10 PM THIS
EVENING. SNOW ASSOCIATED WITH THE CLIPPER WARM FRONT HAS BEEN
ONGOING TODAY IN THE ADVISORY ZONE. SNOWFALL REPORTS OF 4-6 INCHES
HAVE BEEN RECEIVED IN HAMILTON COUNTY. ELSEWHERE REPORTS HAVE
SCARCE. ISENTROPIC ASCENT WILL BE WEAKENING INTO THE EVENING.
STILL A BURST OF SNOW TO GO FOR THE SOUTHERN GREENS.
NEXT ISSUE UP TONIGHT WILL BE THE WIND. A WIND ADVISORY HAS BEEN
ISSUED FOR THE SOUTHERN TWO THIRDS OF THE FORECAST AREA. IN THE
WAKE OF THE SQUALL...STRONG ISENTROPIC DESCENT IN COLD AIR
ADVECTION WILL LEAD TO A WELL MIXED LAYER TAPPING INTO 50 KNOT
WINDS. THE STRONGEST WINDS WILL BE IN CHANNELED FLOW DOWN THE
MOHAWK VALLEY. HERE WE ARE LOOKING FOR WINDS OF 20-30 MPH WITH
GUSTS TO 50 MPH. IN OTHER AREAS WITHIN THE ADVISORY LOOK FOR WINDS
AROUND 20 MPH WITH GUSTS OF 45-50 MPH. STRONGEST WINDS LOOK TO BE
DURING DAYLIGHT HOURS WEDNESDAY MORNING. THE ADVISORY RUNS FROM
1AM TONIGHT TO 5PM WEDNESDAY.
LAKE EFFECT SNOW WARNINGS/ADVISORIES FOR THE WESTERN MOHAWK
VALLEY...SCHOHAIRE COUNTY...AND HELDERBERGS KICK IN THIS EVENING
AND CONTINUE INTO WEDNESDAY EVENING. SEVERE INSTABILITY IS
REALIZED WITH LAKE/850MB TEMPS DELTA T/S AROUND 22C.
UNIDIRECTIONAL WIND ALIGNS ALONG 290-300 VECTOR. THIS PROMOTES
LAKE EFFECT INTO SOUTHERN HERKIMER/SCHOHAIRIE/HELDERBERGS WHERE
HEADLINES ARE FLYING. ALTHOUGH KVIE INLAND EXTENT TOOL SHOWS
RESPECTABLE INLAND PENETRATION OF ABOUT 90-95 MILES GIVEN
TRAJECTORY THIS REACHES SOUTHERN HERKIMER BUT NOT TOO MUCH PAST
THERE. MODELS DO DEPICT BANDS MAKING INTO ADVISORY/WARNING
AREAS...ALTHOUGH QPF IS ON THE LIGHT SIDE. WILL CONTINUE TO
MAINTAIN WARNINGS AND ADVISORIES. FORECAST SNOWFALL IS 6-12 INCHES IN
SOUTHERN HERKIMER AND 3-6 INCHES IN ADVISORY AREAS.
TEMPERATURES TONIGHT WILL SLIDE MAINLY INTO THE TEENS AND
20S...SOME SINGLE DIGITS IN ADIRONDACKS.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
HAVE ADDRESSED WEDNESDAY ABOVE.
AS FAR AS THE REMAINDER OF THE SHORT TERM PERIOD GOES BROAD
CYCLONIC WEST NORTHWEST FLOW WILL KEEP TEMPERATURES ON THE COLD
SIDE OF NORMAL INTO THURSDAY. RISING HEIGHTS AND LIGHT SOUTHWEST
WINDS WILL BRING TEMPERATURES ABOVE NORMAL THURSDAY NIGHT INTO
FRIDAY.
SOME LIGHT LAKE EFFECT SNOW MAY IMPACT NORTHERN HERKIMER AND
HAMILTON COUNTIES ON THURSDAY. A DEVELOPING WARM FRONT ASSOCIATED
WITH A STORM SYSTEM IN THE GREAT LAKES ON FRIDAY COULD BRING SOME
LIGHT PRECIPITATION TO NORTHERN AREAS ON FRIDAY.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
INITIALLY THE LONG TERM PORTION OF THE FORECAST WILL BE
ACTIVE...DESPITE TEMPS REACHING SLIGHTLY ABOVE SEASONAL LEVELS.
THEN...EXPECT A TREND TOWARD DRIER CONDITIONS...BUT TEMPS WILL FALL
A BIT TO SLIGHTLY BELOW NORMAL.
THE MOST CHALLENGING PORTION OF THE FORECAST APPEARS TO BE FRI NT-
SUN AM. MODELS SEEM TO BE CONVERGING SOMEWHAT ON A SOLUTION FAVORING
A COASTAL WAVE...EMANATING FROM THE GULF COAST REGION...WITH AN
INLAND PRIMARY CENTER TRACKING TOWARD THE GREAT LAKES. ASSUMING THE
COASTAL WAVE STRENGTHENS...AND DEVELOPS AS FAR NORTH AND WEST AS
MOST MODELS CURRENTLY SUGGEST...THEN A PERIOD OF MODERATE TO PERHAPS
LOCALLY HEAVY PRECIP IS POSSIBLE. HOWEVER...SHOULD THIS COASTAL WAVE
BE WEAKER AND/OR TRACK SLIGHTLY FARTHER S AND E...THEN MUCH LIGHTER
PRECIP WILL MOST LIKELY OCCUR. ALSO...THE THERMAL PROFILE IS A BIT
IN QUESTION...ESP FOR AREAS SOUTH OF I-90...WHERE H925 TEMPS MAY
INITIALLY BE ABOVE 0C. IF THIS OCCURS...THEN P-TYPE COULD BE
RAIN...OR A RAIN/SNOW MIX FROM I-90 SOUTH...WITH MORE SNOW TO THE
NORTH. THE POSSIBILITY OF MODERATE OR GREATER SNOWFALL AMTS WILL
EXIST...ESP FOR AREAS N OF I-90 AND ACROSS HIGHER TERRAIN...ASSUMING
THE COASTAL ENTITY STRENGTHENS AND TRACKS CLOSER TO THE COAST.
THEREFORE...HAVE LIKELY TO CATEGORICAL POPS FOR LATE FRI NT THROUGH
SATURDAY...THEN TAPERING TO CHC SAT NT-SUN.
BEYOND SUNDAY...THE REMNANTS OF THE PRIMARY LOW ACROSS THE GREAT
LAKES SHOULD MOVE ACROSS SUN-MON...WITH ADDITIONAL SNOW SHOWERS.
THEN...COLDER AIR MOVES INTO THE REGION FOR MON-WED. ADDITIONAL LAKE
EFFECT SNOWFALL WILL BE POSSIBLE ACROSS PORTIONS OF THE WESTERN
ADIRONDACKS/MOHAWK VALLEY.
SOME MODELS SUGGEST ANOTHER SOUTHERN STREAM FEATURE TRACKS TOWARD
THE EAST COAST MON-TUE...BUT AT LEAST FOR NOW...SEEM TO INDICATE A
TRACK FAR ENOUGH S AND E OF THE REGION TO LIMIT ANY IMPACTS TO SOME
CLOUDS.
AS FOR TEMPS...FRI NT/SAT AM MINS SHOULD FALL INTO THE 20S TO LOWER
30S...WARMEST ACROSS THE MID HUDSON VALLEY. ON SAT...MAX TEMPS
SHOULD REACH THE LOWER/MID 30S IN VALLEYS...WITH UPPER 20S ACROSS
HIGHER ELEVATIONS...ALTHOUGH SLIGHTLY COLDER MAX TEMPS COULD OCCUR
IF HEAVIER PRECIP OCCURS EVEN IN VALLEY AREAS FROM I-90 NORTH. SAT
NT/SUN AM MINS SHOULD FALL INTO THE 20S FOR MOST AREAS...PERHAPS
SOME TEENS ACROSS THE ADIRONDACKS.
FOR MON-TUE...MAX TEMPS SHOULD ONLY REACH THE TEENS ACROSS HIGHER
ELEVATIONS...AND LOWER 20S IN VALLEYS. OVERNIGHT MIN TEMPS SHOULD
FALL INTO THE SINGLE DIGITS TO LOWER TEENS...WITH SOME SUBZERO MINS
POSSIBLE TUE NT ACROSS NORTHERN PORTIONS OF THE REGION.
&&
.AVIATION /23Z TUESDAY THROUGH SUNDAY/...
LIGHT SNOW EXITING THE KPSF AREA AND KGFL AREA...AND ACKNOWLEDGING
SOME VISIBILITY AND CEILING RESTRICTIONS THROUGH 01Z UNTIL IT
FULLY EXITS.
THE NEXT THREAT WILL BE WITH SNOW SQUALLS ASSOCIATED WITH A COLD
FRONTAL PASSAGE BETWEEN ROUGHLY 01Z-03Z/WED. A LINE OF SNOW
SQUALLS WILL BE POSSIBLE DURING THIS WINDOW...AND COULD LEAD TO
LIFR/VLIFR VSBYS.
AFTER 03Z/WED...SNOW SHOWERS SHOULD RAPIDLY DECREASE IN AREAL
COVERAGE. HOWEVER...ATTENTION WILL THEN SHIFT TO A POTENTIAL LAKE
EFFECT SNOWBAND...ESP BETWEEN 08Z/WED AND 16Z/WED. WITH A DEVELOPING
W/NW WIND FLOW...IT IS POSSIBLE THAT A SNOWBAND EXTENDS FROM LAKE
ONTARIO TO NEAR OR JUST SOUTH/WEST OF KALB. IFR/LIFR CONDITIONS BE
POSSIBLE WITHIN THIS SNOWBAND. IT COULD ALSO IMPACT KPSF AS WELL
DURING THIS TIME.
WINDS WILL BE VARIABLE BUT MAINLY FROM THE SOUTH THROUGHABOUT 03Z
AT 8-12 KT. THEN...AS THE FRONT PASSES THIS EVENING...WINDS WILL
SHIFT INTO THE WEST/NORTHWEST AND INCREASE TO 10-15 KT...ALONG
WITH SOME GUSTS OF 30-35 KT...ESP AT KALB AND KPSF...THROUGH
18Z/WED...WITH EVEN STRONGER GUSTS POSSIBLE.
ALSO...WITHIN THE HEAVIER SNOW SQUALLS...WINDS COULD BRIEFLY GUST
OVER 25 KT THIS EVENING.
OUTLOOK...
WEDNESDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
THURSDAY: NO OPERATIONAL IMPACT. NO SIG WX.
THURSDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
FRIDAY: NO OPERATIONAL IMPACT. NO SIG WX.
FRIDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SN.
SATURDAY: HIGH OPERATIONAL IMPACT. DEFINITE RA...SN.
SATURDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHSN...SN.
SUNDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN.
&&
.HYDROLOGY...
SEASONABLE TEMPERATURES EXPECTED TO PERSIST THROUGH NEXT WEEK.
THIS WILL ALLOW FOR ICE TO FORM ON BODIES OF WATER ALONG WITH
SNOW.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...WIND ADVISORY FROM 1 AM TO 5 PM EST WEDNESDAY FOR CTZ001-013.
NY...WIND ADVISORY FROM 1 AM TO 5 PM EST WEDNESDAY FOR NYZ038>040-
047>054-058>061-063>066.
LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST WEDNESDAY FOR NYZ039-
040-047-048-051.
WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR
NYZ032-033-042-082.
LAKE EFFECT SNOW WARNING UNTIL 7 PM EST WEDNESDAY FOR NYZ038.
MA...WIND ADVISORY FROM 1 AM TO 5 PM EST WEDNESDAY FOR MAZ001-025.
VT...WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR
VTZ014.
&&
$$
SYNOPSIS...OKEEFE
NEAR TERM...OKEEFE/NAS
SHORT TERM...OKEEFE
LONG TERM...KL
AVIATION...NAS
HYDROLOGY...IAA/11
AREA FORECAST DISCUSSION
NWS TAUNTON MA
611 PM EST TUE JAN 12 2016
.SYNOPSIS...
LOW PRESSURE OVER SOUTHERN ONTARIO WILL REDEVELOP IN THE GULF OF
MAINE TONIGHT AND INTENSIFY AS IT MOVES INTO THE MARITIMES
WEDNESDAY MORNING. THIS STORM WILL BRING LIGHT ACCUMULATING SNOW
TO THE INTERIOR OF SOUTHERN NEW ENGLAND THIS EVENING...WITH RAIN
ENDING AS SNOW SHOWERS ALONG THE COASTAL PLAIN. WINDY AND COLD
CONDITIONS WILL FOLLOW LATER TONIGHT INTO WEDNESDAY NIGHT.
HIGH PRESSURE BUILDS ACROSS THE REGION INTO FRIDAY. A LULL BEFORE
A RAPIDLY DEEPENING STORM SYSTEM FOR SATURDAY WHICH WILL BRING A
COMBINATION OF WINTER AND WIND THREATS FOR S NEW ENGLAND. QUIETER
COLD WEATHER FOLLOWS FOR SUNDAY ON THROUGH THE FOLLOWING WEEK.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
6 PM UPDATE ...
MID-LEVEL SHORTWAVE PUSHING IN FROM THE W INVOKING CYCLOGENESIS
INTO THE GULF OF MAINE AS OBSERVED FROM THE LATEST 3-HOUR PRESSURE
FALLS. ISALLOBARIC RESPONSE OF STRONG SW MOIST-CONVERGENCE AS
COLDER AIR PRESSES IN THE FROM THE W. DEEP-LAYER ASCENT BENEATH
BROADER DIFFLUENCE ALOFT THROUGH A STEEP UNSTABLE PROFILE ON UP
TO H5 AS THE ATMOSPHERIC COLUMN COOLS AND MOISTENS ... AND WHAT WE
ARE OBSERVING PER WSR-88D IS SUBSEQUENT ... A BROAD AREA OF PRECIP
WITH EMBEDDED STRONGER/HEAVIER RETURNS ... SOME OF WHICH BECOMING
UNSTABLE ENOUGH TO PRODUCE LIGHTNING. OVERALL ... THE OUTCOMES OF
SUCH WEATHER IS DEPENDENT ON THE SURFACE TEMPERATURE TO WHICH BASED
ON OBSERVATIONS AND WET-BULB PROCESSES ... SNOW IS OCCURRING AT
36-DEGREES.
FORECAST MODEL CONSENSUS OF THE NAM / WRF / HRRR PREFERRED. EXPECT
THIS FIRST WAVE TO FOCUS OVER E NEW ENGLAND PRIOR TO PUSHING
OFFSHORE OVER THE NEXT FEW HOURS. IMPACTS OF ACCUMULATIONS MAINLY
CONFINED TO ELEVATED / GRASSY SURFACES. BIGGER IMPACT IS THE
REDUCTION IN VISIBILITIES DOWN TO A QUARTER MILE OR LESS. AS THE
INITIAL WAVE MOVES OFFSHORE ... LULL IN BETWEEN ... THEN FOCUS
SHIFTS TO THE W ON THE SQUALL LINE WHICH PERHAPS MAY NOT MAKE IT
PAST THE BERKSHIRES VIA DOWNSLOPING W-WINDS AS THE MODEL CONSENSUS
SUGGESTS. WILL HAVE TO WATCH THIS CLOSELY ... COULD SEE SOME
REMNANTS GENERATE ISSUES ACROSS THE INTERIOR.
OVERALL ... LOOKING AT A COATING TO 1-INCH FOR MOST LOCATIONS ...
WITH 1-2 INCHES OVER THE HIGHER TERRAIN AND MORE N/W. LOCALLY
HIGHER AMOUNTS ON UP TO 3-INCHES POSSIBLE ... MAINLY THINKING
BERKSHIRES AND N WORCESTER HILLS.
RAIN MAINLY CONFINED TO THE S/SE-COASTS INCLUDING THE CAPE AND
ISLANDS ... THOUGH MAY CONCLUDE AS SNOW AS THE STORM SYSTEM LIFTS
OUT WITH LITTLE TO NO ACCUMULATION. AFTERWARDS WILL SEE W-WINDS ON
THE INCREASE AS THE OFFSHORE STORM AMPLIFIES AS HIGH PRESSURE
BUILDS IN FROM THE W. GUSTY W-WINDS UP TO 45 MPH TOWARDS MORNING
SUBSEQUENT OF THE GRADIENT RESPONSE. WIND ADVISORIES REMAIN IN
EFFECT.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/...
WEDNESDAY...
PRESSURE GRADIENT FOLLOWING THE MARITIME LOW WILL BE SUFFICIENT
TO KEEP WINDS GOING THROUGH THE MORNING AND EARLY AFTERNOON. THE
GRADIENT DIMINISHES DURING THE AFTERNOON. CONTINUE THE WIND
ADVISORY UNTIL 22Z. LINGERING MOISTURE AT 850 MB SUGGESTS SOME SKY
COVER DURING THE DAY. EVEN SO...MIXING LEVELS SHOULD REACH CLOSE
TO 850 MB. TEMPS AT THAT LEVEL WILL BE AROUND -15C TO -17C...
SUPPORTING MAX TEMPS MID 20 TO LOW 30S. WIND CHILLS WILL BE IN
THE SINGLE NUMBERS AND TEENS.
WEDNESDAY NIGHT...
HIGH PRESSURE BUILDS OVER THE REGION BRINGING A FAIR DRY NIGHT.
WINDS WILL CONTINUE TO DIMINISH EARLY. INCREASED MOISTURE ALOFT
MOVES IN FROM THE WEST LATE AT NIGHT...SO POSSIBLE CLOUDS LATE.
THE AIRMASS WILL BE COOLER THAN TONIGHT...SO MIN TEMPS IN THE
TEENS LOOK REASONABLE.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
*/ HIGHLIGHTS ...
- SNOWS AND WINDS TAPERING THURSDAY AS HIGH PRESSURE BUILDS IN
- RAPIDLY DEEPENING STORM WILL BRING RAIN/SNOW FOR SATURDAY
- WINTER / WIND HEADLINES POSSIBLE WITH EXPECTED THREATS / IMPACTS
- QUIET YET COLD PATTERN FOR SUNDAY INTO NEXT WEEK
*/ OVERVIEW ...
COMBINATION OF FACTORS LENDING TO A PROLONGED PERIOD OF QUICK-MOVING
STORMS FOLLOWED BY SHOTS OF ARCTIC AIR. A MADDEN-JULIAN OSCILLATION
SHIFTING FROM PHASE 8 TOWARDS 2 ... SEEING STRONG WESTERLIES ALONG
THE S-STREAM FROM THE W-EQUATORIAL PACIFIC NE INTO THE NW ATLANTIC.
PROMOTING A +PNA ... N-STREAM IMPULSES TROUGH ACROSS THE E MEETING
UP WITH THE S-STREAM. WITH NO BLOCKING DOWNSTREAM ... A PROGRESSIVE
PATTERN EMERGES ALLOWING QUICK-MOVING STORMS TO AMPLIFY LATER ACROSS
THE N ATLANTIC LENDING TO A FAIR AMOUNT OF TRADING OF SUB-TROPICAL
AIR N WHILE ARCTIC / STRATOSPHERIC AIR DIVES S ACROSS THE N AMERICAN
CONTINENT. THE POLAR JET WEAKENS SUBSEQUENTLY AND HENCE THE -NAO/-AO
TREND AS OF LATE. THE AMPLITUDE OF COLDER AIR S IS SUSTAINED BY THE
INCREASING SNOW DEPTH OVER CANADA ... WHICH HAS GREATLY INCREASED AS
OF LATE N/W OF THE ST LAWRENCE RIVER VALLEY.
SO IT APPEARS WINTER IS HERE. PACIFIC-ORIGIN ENERGY TROUGHS TOWARDS
S-STREAM ENERGY AND STRONGER WESTERLIES / BAROCLINICITY. WITH NO
DOWNSTREAM BLOCKING ... STORM SYSTEMS SWEEP IN PROXIMITY TO THE NE-
CONUS DURING THE MATURATION PHASE. AN INITIAL WARM-SHOT IS QUICKLY
FOLLOWED BY ARCTIC AIR. ITS THE TRANSITION OF THE TWO PARENT WITH
THE TIMING / STRENGTH / PROXMITY OF THE STORM TO S NEW ENGLAND THAT
WILL OUTLINE IN DETAIL BELOW ... NOTING POTENTIAL OUTCOMES/IMPACTS.
*/ DISCUSSION ...
THURSDAY ...
CYCLONIC W-WINDS REMAINING STOUT BENEATH WEAK H5 TROUGHING AND
ATTENDANT MID-LEVEL ENERGY ALOFT. ACCOMPANYING ARCTIC AIR AND MINOR
CONTINENTAL MARITIME MOISTURE ... LOOKING AT A MIX OF SUN AND CLOUDS
INITIALLY PER MIXING AND ASCENT WITH THE LAKE / OCEAN EFFECT SNOWS
AND BREEZY WINDS ... BOTH TAPERING THROUGH THE DAY AS HIGH PRESSURE
BUILDS IN. CONCERNS ALONG THE BERKSHIRES AND OUTER-ARM OF THE CAPE
ALONG WITH NANTUCKET FOR ACCUMULATING SNOWS AND REDUCED VISIBILITIES.
DESPITE HIGH PRESSURE FEEL ANY CLEARING THOUGH IS SHORT-LIVED AS
ISENTROPIC LIFT OF WARM-MOIST AIR PRECEDES THE LATE-WEEK INTO
WEEKEND STORM SYSTEM. SHOULD KEEP IT SOMEWHAT MILD OVERNIGHT.
FRIDAY INTO SATURDAY ...
DOUBLE-BARREL LOW / MILLER-B TYPE SIGNATURE? NEVERTHELESS STORM
SYSTEM APPROACHING TOWARDS SATURDAY MORNING RAPIDLY DEEPENING ACROSS
THE 40N/70W BENCH-MARK POTENTIALLY DOWN TO 980-970 MB ... QUICKLY
EXITING LATE. FORECAST GUIDANCE CONSENSUS PREFERRED AS THERE IS GOOD
CLUSTERING WITH DETERMINISITIC / ENSEMBLE SOLUTIONS ... MINUS THE
CANADIAN /WOMP WOMP/.
COMPLICATIONS: LACK OF ARCTIC AIRMASS ACROSS CANADA CONSIDERING N-
WINDS WITH ISALLOBARIC RESPONSE ... QUICK DAYTIME PASSAGE ... SOME
UNCERTAINTY AS TO WHETHER THE STORM UNDERGOING MATURATION CLOSES-OFF
COMPLETELY DURING IMPACT /POTENTIAL TROWALING/ ... THERMAL PROFILES
AND SUBSEQUENT RAIN / SNOW TRANSITION LINES ... ALONG WITH SNOW-TO-
LIQUID RATIOS /POTENTIALLY ISOTHERMAL UP TO H7 NEAR-FREEZING ...
PERHAPS A MORE WET-SNOW ... HEAVY PACKING WITH ACCUMULATION/.
OVERALL LOOKING LIKE A RAIN/SNOW SETUP WHERE THICKNESSES AND THERMAL
PROFILES ARE KEY. A CONSENSUS OF FORECAST GUIDANCE AS NOTED ALONG
WITH CIPS ANALOGS ... LOOKING AT A SW-NE TRANSITION LINE WITH
COASTAL-FRONT INFLUENCES PER ONSHORE FLOW. ACCUMULATING SNOWS AWAY
FROM THE SHORE AND COASTAL PLAINS ... ACROSS THE N/W INTERIOR WITH
FOCUS ALONG THE E-SLOPES OF HIGH TERRAIN. COULD SEE A LOT OF
MOISTURE WITH THIS SYSTEM WITH CONSENSUS PRECIPITATION AMOUNTS IN
EXCESS OF AN INCH. THERE IS SOME POSSIBILITY WE WILL BE CONTENDING
WITH WINTER WEATHER HEADLINES. THIS IN ADDITION WITH A ROBUST
DEEPENING SYSTEM ... COULD BE DEALING WITH WIND HEADLINES AS WELL
ALONG THE COAST / COASTAL PLAINS.
AS THE SYSTEM LIFTS OUT LATE ... RAIN TRANSITIONING BACK TO SNOW
TURNING LIGHT. PERHAPS SOME LIGHT ACCUMULATIONS PRIOR TO EVERYTHING
WINDING DOWN ALONG WITH WINDS.
REST OF THE WEEKEND INTO NEXT WEEK ...
CONTINUED ENERGY THROUGH THE PREFERRED TROUGHING PATTERN TOWARDS
MIDWEEK. BETTER BAROCLINICITY / MOISTURE WELL S AND E ALONG WITH THE
MORE FAVORABLE STORM TRACK ... FORECAST MODELS INDICATE SOME CLIPPER-
TYPE ENERGY AROUND SUNDAY NIGHT ... OTHERWISE ARCTIC AIR BUILDS BACK
INTO THE REGION PROMOTING MIXING AND ASCENT YIELDING ANOTHER ROUND
OF LAKE / OCEAN EFFECT SNOWS. HIGH PRESSURE FOLLOWS INTO THE LATE
WEEK PERIOD. THEREAFTER COULD BE A WASH RINSE REPEAT OF THE PATTERN.
CIPS ANALOGS WOULD CONTEND THAT OVERALL LOOKING AT A GOOD CHANCE OF
BELOW-AVERAGE TEMPERATURES.
&&
.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH WEDNESDAY NIGHT/ ...
TONIGHT ... HIGH CONFIDENCE.
RAIN / SNOW BAND ACROSS E NEW ENGLAND THE NEXT COUPLE OF HOURS.
MVFR WITH RAIN. IFR WITH SNOW. BRIEF LULL PRIOR TO SCT SNOW-SQUALL
ACTIVITY CLOSER TO MIDNIGHT ... MAINLY W/CENTRAL NEW ENGLAND.
TEMPO IFR POSSIBLE. BEHIND WHICH W-WINDS INCREASE WITH GUSTS BY
MORNING REACHING 35 TO 40 KTS.
WEDNESDAY ... HIGH CONFIDENCE.
VFR. W/NW-GUSTS 35 TO 40 KTS DIMINISHING MID TO LATE AFTERNOON.
WEDNESDAY NIGHT ... HIGH CONFIDENCE.
VFR. W-GUSTS TO 25 KTS DURING THE EVENING THEN DIMINISHING.
KBOS TERMINAL...
WILL HOLD WITH MAINLY RAIN OVER THE NEXT FEW HOURS WITH SOME -SN
MIXING IN. NO ACCUMULATION ANTICIPATED ... JUST WET RUNWAYS.
CONCERN MORE SO AFTER MIDNIGHT TOWARDS MORNING WITH INCREASING
W-WINDS GUSTING UPWARDS OF 40 KTS.
KBDL TERMINAL...
WORST OF CONDITIONS HAVE PUSHED THROUGH. SHOULD SEE IMPROVEMENT TO
MVFR / LOW-END VFR. TEMPO IFR POSSIBLE WITH ADDITIONAL SNOW-SQUALL
ACTIVITY PRIOR TO MIDNIGHT ... BUT LOW CONFIDENCE. AFTER MIDNIGHT
INCREASING W-GUSTS.
OUTLOOK /THURSDAY THROUGH SUNDAY/... MODERATE CONFIDENCE.
THURSDAY ...
SCT-BKN LOW-END VFR CIGS WITH MVFR ACROSS HIGH TERRAIN INITIALLY.
BREEZY W-WINDS TAPERING TOWARDS LATE.
FRIDAY INTO SATURDAY ...
CONDITIONS LOWERING INTO SATURDAY MORNING. RAIN S/E ... SNOW N/W.
MIX MVFR-LIFR WITH WORST CONDITIONS ALONG S/SE COAST AND COASTAL
PLAIN ... AND N/W HIGH TERRAIN. STRONG E/NE GUSTS ACROSS SE NEW
ENGLAND POTENTIALLY REQUIRING WIND HEADLINES. CONDITIONS BEGIN TO
IMPROVE LATE WITH -SN LINGERING.
SUNDAY ...
CONDITIONS IMPROVING. PERHAPS SOME LIGHT SNOW TAPERING EARLY. WINDS
DIMINISHED. BECOMING VFR.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH WEDNESDAY NIGHT/...HIGH CONFIDENCE.
TONIGHT AND WEDNESDAY... GALE WARNINGS CONTINUE FOR ALL WATERS
FOR LATE TONIGHT INTO WEDNESDAY. SOUTH WINDS SHIFT TO WEST BY
MIDNIGHT AND INCREASE WITH GUSTS TO 40-45 KT LATE NIGHT INTO
WEDNESDAY AS LOW PRESSURE INTENSIFIES IN THE MARITIMES. SEAS
BUILDING TO 10-14 FT OVER THE OUTER WATERS. RAIN/SNOW THIS EVENING
ENDING AS A BRIEF PERIOD OF SNOW TONIGHT.
WEDNESDAY NIGHT... DIMINISHING WEST WINDS THROUGH THE NIGHT. WINDS
BELOW GALE ON ALL WATERS BY MIDNIGHT BUT LINGERING 25 KNOT WINDS
THROUGH THE NIGHT. SEAS ALSO DIMINISH BUT WITH LINGERING 5 FOOT
SEAS ON THE OUTER WATERS ALL NIGHT.
OUTLOOK /THURSDAY THROUGH SUNDAY/ ... MODERATE CONFIDENCE.
THURSDAY ...
BREEZY W-WINDS WITH OCEAN EFFECT SNOWS INITIALLY. LIKELY SOME
VISIBILITY RESTRICTIONS AT TIMES. SMALL-CRAFT ADVISORIES HOLDING.
CONDITIONS ALONG WITH WAVES DIMINISH LATE INTO FRIDAY MORNING.
FRIDAY INTO SATURDAY ...
THOUGH A LULL IN WIND AND WAVE ACTIVITY TOWARDS SATURDAY MORNING ...
IT ALL GOES DOWNHILL FROM THERE. STORM RAPIDLY DEEPENS TOWARDS THE
40N/70W BENCHMARK ... EXITING QUICKLY LATE. ANTICIPATING E/NE GALES
POTENTIALLY ON UP TO STORM FORCE ALONG WITH RAINS WITH EMBEDDED
HEAVIER SHOWERS YIELDING VISIBILITY RESTRICTIONS. WAVES BUILDING
UPWARDS OF 15 FEET ON THE OUTER WATERS. CONDITIONS TAPER LATE INTO
SUNDAY MORNING. MOST OF THE IMPACTS DURING THE DAY SATURDAY.
SUNDAY ...
CONDITIONS IMPROVING. PERHAPS SOME LIGHT SNOW TAPERING EARLY. N/W
WINDS DIMINISHING ALONG WITH WAVE ACTIVITY ... BUT LIKELY SMALL-
CRAFT ADVISORIES WILL NEED TO REMAIN.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...WIND ADVISORY FROM 1 AM TO 5 PM EST WEDNESDAY FOR CTZ002>004.
MA...WIND ADVISORY FROM 1 AM TO 5 PM EST WEDNESDAY FOR MAZ002>024-
026.
RI...WIND ADVISORY FROM 1 AM TO 5 PM EST WEDNESDAY FOR RIZ001>008.
MARINE...GALE WARNING FROM 1 AM TO 9 PM EST WEDNESDAY FOR ANZ232>234.
GALE WARNING FROM 3 AM TO 6 PM EST WEDNESDAY FOR ANZ230.
GALE WARNING FROM 3 AM TO 7 PM EST WEDNESDAY FOR ANZ231-251.
GALE WARNING FROM 1 AM TO 6 PM EST WEDNESDAY FOR ANZ236.
GALE WARNING FROM 10 PM THIS EVENING TO 9 PM EST WEDNESDAY FOR
ANZ235-237.
GALE WARNING FROM 1 AM WEDNESDAY TO 1 AM EST THURSDAY FOR
ANZ250-254.
GALE WARNING FROM 10 PM THIS EVENING TO 11 PM EST WEDNESDAY
FOR ANZ255-256.
&&
$$
SYNOPSIS...WTB/SIPPRELL
NEAR TERM...WTB/SIPPRELL
SHORT TERM...WTB
LONG TERM...SIPPRELL
AVIATION...WTB/SIPPRELL
MARINE...WTB/SIPPRELL
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 GRAY ME
1025 PM EST TUE JAN 12 2016
.SYNOPSIS...
LOW PRESSURE MOVING ACROSS THE GULF OF MAINE TONIGHT WILL
INTENSIFY AS IT MOVES NORTHEAST INTO THE MARITIMES ON WEDNESDAY.
THIS WILL PRODUCE A ROUND OF SNOW TONIGHT...HEAVY AT TIMES ACROSS
CENTRAL AND MIDCOAST MAINE. AS THE STORM EXITS IT WILL ALSO
PRODUCE WINDY BUT FAIR CONDITIONS ON WEDNESDAY. HIGH PRESSURE
BUILDS IN THURSDAY AND FRIDAY. ANOTHER ROUND OF SNOW...POSSIBLY
RAIN NEAR THE COAST IS EXPECTED ON SATURDAY...WITH COLDER AIR
MOVING IN SUNDAY AND MONDAY.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
1020 PM UPDATE...HAVE UPDATED THE FORECAST BASED ON LATEST TRENDS
IN RADAR AND OTHER OBSERVATIONAL DATA. THE BACK EDGE OF THE HEAVY
SNOW SHIELD IS MOVING QUICKLY TO THE NORTHEAST ACROSS SOUTHERNMOST
ME AND THIS TREND WILL CONTINUE. RAIN HUGGING THE MAINE COAST WILL
GRADUALLY GO BACK OVER TO SNOW OVER THE NEXT FEW HOURS FROM SOUTH
TO NORTH. HAVE CANCELLED THE ADVISORIES FOR SOUTHERN NH AS THE
SNOW HAS ENDED THERE. A FEW SQUALLS MAY AFFECT WESTERN ZONES
OVERNIGHT HOWEVER.
PREVIOUSLY...
A POTENT S/WV TROF IS CROSSING THE ERN GREAT LAKES AT THIS
HOUR...AND WILL BRING SOME SIGNIFICANT IMPACTS TO THE AREA THIS
EVENING AND TONIGHT.
THE STRENGTH OF THIS S/WV IS EVIDENT IN THE WILD WX THIS
AFTERNOON ACROSS UPSTATE NY. THUNDER HAS BEEN REPORTED AROUND BUF
IN HEAVY SNWFL...WITH WIND GUSTS IN EXCESS OF 60 MPH. THESE
SQUALLS MARK THE LEADING EDGE OF THE S/WV TROF. AHEAD OF
IT...INCREASING SLY FLOW AND WAA IS ALLOWING LIGHT SNWFL TO BREAK
OUT. THIS WILL INCREASE IN COVERAGE AND INTENSITY AS THE S/WV
APPROACHES. THIS WILL LEAD TO MINOR ACCUMULATIONS THRU THE EVENING
COMMUTE...BUT COULD LEAD TO SLIPPERY ROADS WITH TEMPS NEAR
FREEZING.
ATTENTION THEN TURNS TO THAT LEADING EDGE OF THE S/WV AND
ATTENDANT SQUALLS. HI-RES MODEL GUIDANCE SUGGESTS IT BECOMES
DIFFICULT TO DISTINGUISH BETWEEN THE LINE OF SN SHOWERS AND THE
DEVELOPING STRONG INFLOW JET FORECAST TO FORM NEAR SERN NH. 12Z
MODEL GUIDANCE SHIFTED THIS AREA OF FORMATION SLIGHTLY SW FROM 00Z
MODEL SUITE. THIS BRINGS AREAS LIKE MHT AND ASH A LITTLE CLOSER TO
THE BRIEF HEAVY SNWFL THREAT. HRRR GUIDANCE...ALONG WITH
ARW...NMM...AND REGIONAL CMC ALL SHOW THE POTENTIAL FOR QPF...AND
THUS SNWFL...TO BRIEFLY BE HEAVY AS THIS INFLOW JET SWEEPS NEWD
THRU THE FORECAST AREA. SNWFL RATES MAY EXCEED 1 TO 3 INCHES PER
HOUR IN THE HEAVIEST SNWFL...THOUGH MAY ONLY LAST FOR AN HOUR OR
SO. MIXING ANY OF THAT WIND ALOFT DOWN IN HEAVY SHOWERS COULD ALSO
BRING 30 TO 35 MPH GUSTS...WHICH WOULD LEAD TO NEAR ZERO
VISIBILITY AT TIMES. I HAVE AN SPS IN EFFECT TO HIGHLIGHT THIS
SHORT DURATION...HEAVY SNWFL ASPECT OF THE SYSTEM. IN
ADDITION...LAPSE RATES ALOFT EXCEED 7 C/KM...SUFFICIENT FOR STRONG
WARM SEASON CONVECTION LET ALONE WINTER. WILL KEEP THUNDER IN THE
FORECAST FOR AREAS NEAR THE COAST WHERE THIS UNSTABLE AIR MASS IS
ABLE TO MOVE IN OFF THE WATER. ANY CONVECTION WILL FURTHER ENHANCE
THOSE SNWFL RATES.
S/WV TROF CONTINUES NEGATIVE TILT THRU THE AREA...AND BAND OF
SNWFL SHOULD BEGIN TO SLOW AND PIVOT AS IT APPROACHES CENTRAL ME.
HEAVIEST AMOUNTS WILL BE IN OUR ERN ZONES...GENERALLY FROM AUG
NEWD. AGAIN WILL HAVE TO MONITOR BOUNDARY LAYER TEMPS NEAR THE
COAST...AS MODELS CONTINUE TO SUGGEST WARMING MAKING IT WELL
INLAND. TEMPS ALOFT WOULD ARGUE THAT THIS STRUGGLES TO MAKE
PROGRESS MUCH PAST THE NECKS AND ISLANDS. CAPE ELIZABETH AND MAYBE
EVEN PWM MAY BE RA...WHILE THE TURNPIKE IS HEAVY SNWFL. HOWEVER
TOO MUCH UNCERTAINTY EXISTS TO CHANGE HEADLINES FROM WHERE WE HAVE
THEM CURRENTLY. SNWFL AMOUNTS LOOK VERY SIMILAR TO PREVIOUS
SHIFT...MAYBE SLIGHTLY HIGHER OVER SWRN ME. HOWEVER THESE STILL
FALL WITHIN ADVISORY RANGE. STILL A LOW CHANCE THAT SOME OF THE
ADVISORY MAY NEED TO BE CONVERTED TO WARNINGS AS THE BANDING SETS
UP.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/...
LOW PRES DEEPENS INTO THE 970S OVER THE CANADIAN MARITIMES
WED...SETTING UP A STRONG PRES GRADIENT ACROSS THE AREA. FLOW IN
CAA WILL BECOME GUSTY EARLY WED...INCREASING IN THE AFTERNOON AS
THE CORE OF WLY JET AROUND 5000 FEET MOVES OVERHEAD. BUFKIT
SOUNDINGS SHOW SOME POTENTIAL TO MIX DOWN SOME OF THIS JET...WITH
A FEW MODELS SHOWING GUSTS IN THE 40 TO 45 KT RANGE. GIVEN THAT A
WIND HEADLINE WOULD COMPLICATE AN ALREADY COMPLICATED FORECAST
EVEN FURTHER...WILL HOLD OFF FOR NOW AND ALLOW THE MIDNIGHT SHIFT
TO REASSESS.
UPSLOPE SN SHOWERS WILL LINGER OVER THE NRN ZONES IN WLY FLOW WED.
AN ADDITIONAL COUPLE OF INCHES IS POSSIBLE IN THE FAVORED AREAS.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
HIGH IMPACT WX: LOW CONFIDENCE FOR SIGNIFICANT SNOW CENTERED
AROUND SATURDAY.
THE 500 MB PATTERN CONTINUES TO BUILD WEAK TO MODERATE RIDGING
ACROSS THE WRN CONUS AND ERN PACIFIC...WITH A MEAN...BUT
FLUCTUATING TROUGH OVER THE ERN CONUS. ALL IN ALL THOUGH...SO
CALLED PINEAPPLE EXPRESS ACROSS THE PACIFIC WILL PROVIDE ENOUGH
WAVES TO CONTINUALLY KNOCK DOWN THE RIDGE IN THE WEST...AND LACK
OF COLD AIR OVER NOAM WILL LIMIT THERMAL ADVECTION ENOUGH IN THE
ARCTIC TO MINIMIZE WAVE PRODUCTION TO MAINTAIN SOLID TROUGH OVER
ERN CONUS. THIS...WILL SEE SOME CHANGEABLE CONDS THRU THE EXTENDED
WITH TEMPS FLUCTUATING SEVERAL DEGREES EITHER SIDE OF NORMAL.
SENSIBLE WX WILL SEE SFC RIDGE SLOWLY PASSING TO OUR S THU AND
FRI...WITH SFC LOW MOVING NE INTO THE GREAT LAKES FRI NIGHT. 500MB
WEAVE ROTATING AROUND THE BASE OF THE TROUGH WILL DEVELOP COASTAL
BY SAT MORNING WHICH TRACKS OFF NEW ENGLAND COAST SAT. THIS WILL
BE OUT NEXT PRECIP MAKER. MED RANGE MODELS IN BETTER AGREEMENT ON
TIMING...WITH PRECIP STARTING SOMETIME FRI NIGHT AND ENDING SAT
NIGHT. TRACK AND INTENSITY FORECASTS VARY QUITE A
BIT...PARTICULARLY WHERE P-TYPE AND INTENSITY ARE CONCERNED WITH
THE GFS MOVING THE LOW FURTHEREST OFFSHORE...WHILE THE GGEM IS THE
CLOSEST...WITH THE EURO IN THE MIDDLE. SO WHILE SOME PRECIP CAN BE
EXPECTED...AND IT WILL LIKELY BE SNOW INLAND...EVERYTHING ELSE
STILL REMAINS LOW CONFIDENCE. UPPER LVL LOW CROSSES THE REGION
SUNDAY WITH SHSN POSSIBLE...AND COLDER HIGH PRESSURE EXPECTED
EARLY NEXT WEEK.
&&
.AVIATION /04Z WEDNESDAY THROUGH SUNDAY/...
SHORT TERM...CONDITIONS WILL IMPROVE RAPIDLY FROM SW TO NE LATE
THIS EVENING AND OVERNIGHT AS THE SNOW SHIELD MOVES NORTHEASTWARD.
GUSTY WEST WINDS AND VFR CONDITIONS WILL FOLLOW LATER TONIGHT AND
WEDNESDAY.
LONG TERM...VFR WED NIGHT THROUGH FRI. FLIGHT RESTRICTIONS
EXPECTED LATE FRI NIGHT INTO SAT EVE IN SN...OR POSSIBLE RA NEAR
THE COAST. SOME IMPROVEMENT IS POSSIBLE ON SUN.
&&
.MARINE...
SHORT TERM...GALE WARNINGS REMAIN IN EFFECT FOR ALL WATERS THRU
WED. WINDS MAY GUST TO NEAR STORM FORCE FOR A TIME IN STRONG CAA
WED.
LONG TERM...WINDS GRADUALLY DIMINISH FROM GALES WED EVE...TO SCA
FOR THU....AND BELOW SCA THU NIGHT THRU FRI NIGHT. SCA OR GALES
POSSIBLE AGAIN SAT AND SAT NIGHT.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...WINTER WEATHER ADVISORY UNTIL 4 AM EST WEDNESDAY FOR MEZ007-
012-019-020.
WINTER STORM WARNING UNTIL 10 AM EST WEDNESDAY FOR MEZ008-009-
013-014-021-022-028.
WINTER WEATHER ADVISORY UNTIL 1 AM EST WEDNESDAY FOR MEZ018-
023-024.
WINTER WEATHER ADVISORY UNTIL 10 AM EST WEDNESDAY FOR
MEZ025>027.
NH...WINTER WEATHER ADVISORY UNTIL 4 AM EST WEDNESDAY FOR
NHZ001>004-006.
MARINE...GALE WARNING UNTIL 11 PM EST WEDNESDAY FOR ANZ150>154.
&&
$$
NEAR TERM UPDATE...EKSTER
SHORT TERM...LEGRO
LONG TERM...CEMPA
AREA FORECAST DISCUSSION
NWS GRAY ME
747 PM EST TUE JAN 12 2016
.SYNOPSIS...
LOW PRESSURE MOVING ACROSS THE GULF OF MAINE TONIGHT WILL
INTENSIFY AS IT MOVES NORTHEAST INTO THE MARITIMES ON WEDNESDAY.
THIS WILL PRODUCE A ROUND OF SNOW TONIGHT...HEAVY AT TIMES ACROSS
CENTRAL AND MIDCOAST MAINE. AS THE STORM EXITS IT WILL ALSO
PRODUCE WINDY BUT FAIR CONDITIONS ON WEDNESDAY. HIGH PRESSURE
BUILDS IN THURSDAY AND FRIDAY. ANOTHER ROUND OF SNOW...POSSIBLY
RAIN NEAR THE COAST IS EXPECTED ON SATURDAY...WITH COLDER AIR
MOVING IN SUNDAY AND MONDAY.
&&
00Z UPDATE...
MAIN EVENT CURRENTLY PUSHING EAST THROUGH NEW HAMPSHIRE AND
WESTERN MAINE EARLY THIS EVENING. EXPECT HEAVIEST SNOWFALL RATES
OVER THE NEXT 1 TO 3 HOURS IN EASTERN NEW HAMPSHIRE AND ADJACENT
WESTERN MAINE WHERE AN INCH OR MORE PER HOUR WILL FALL. COASTAL
FRONT IS WAVERING ALONG THE COAST WITH SNOW MIXING WITH RAIN IN
PORTSMOUTH. BETTER VERTICAL MOTION PUSHING INTO THAT AREA IN THE
NEXT HOUR MAY BE ENOUGH CHANGE PRECIP BACK TO ALL SNOW BEFORE
TAPERING OFF AROUND 900 PM.
FARTHER EAST PORTLAND SEEING SOME ENHANCEMENT FROM ONSHORE FLOW
PRODUCING OCCASIONALLY MODERATE BURSTS. MAY SEE SOME MIXING FROM
TIME TO TIME IN PORTLAND BUT EXPECT MOST OF IT TO BE IN THE FORM
OF SNOW. FARTHER DOWNEAST ROCKLAND STARTED OUT AS RAIN BUT HAS
GONE OVER TO A MIX AND WILL BE TRANSITIONING TO SNOW OVER THE NEXT
HOUR OR TWO.
RADAR SHOWING BACK EDGE OF PRECIP DEPARTING THE CONNECTICUT VALLEY
BUT SURFACE OBS STILL REPORTING LIGHT SNOW AND EXPECT THAT TO
CONTINUE UNTIL FROPA AROUND 10 PM. FRONT CURRENTLY PUSHING THROUGH
EASTERN NEW YORK WITH ANOTHER BAND OF LIGHT TO MODERATE SNOW
WHICH WILL CROSS THE REGION LATER THIS EVENING. CURRENT SNOW
ACCUMULATIONS SEEM TO BE FALLING IN LINE WITH FORECAST AMOUNTS BUT
MAY HAVE TO MAKE SOME ADJUSTMENTS LATER THIS EVENING...ESPECIALLY
IN COASTAL ZONES. HAVE TWEAKED TEMPS/TD`S/POPS BASED ON LATEST
SURFACE OBS AND RADAR TRENDS. NO OTHER CHANGES PLANNED ATTM.
PREVIOUS DISCUSSION...
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
A POTENT S/WV TROF IS CROSSING THE ERN GREAT LAKES AT THIS
HOUR...AND WILL BRING SOME SIGNIFICANT IMPACTS TO THE AREA THIS
EVENING AND TONIGHT.
THE STRENGTH OF THIS S/WV IS EVIDENT IN THE WILD WX THIS
AFTERNOON ACROSS UPSTATE NY. THUNDER HAS BEEN REPORTED AROUND BUF
IN HEAVY SNWFL...WITH WIND GUSTS IN EXCESS OF 60 MPH. THESE
SQUALLS MARK THE LEADING EDGE OF THE S/WV TROF. AHEAD OF
IT...INCREASING SLY FLOW AND WAA IS ALLOWING LIGHT SNWFL TO BREAK
OUT. THIS WILL INCREASE IN COVERAGE AND INTENSITY AS THE S/WV
APPROACHES. THIS WILL LEAD TO MINOR ACCUMULATIONS THRU THE EVENING
COMMUTE...BUT COULD LEAD TO SLIPPERY ROADS WITH TEMPS NEAR
FREEZING.
ATTENTION THEN TURNS TO THAT LEADING EDGE OF THE S/WV AND
ATTENDANT SQUALLS. HI-RES MODEL GUIDANCE SUGGESTS IT BECOMES
DIFFICULT TO DISTINGUISH BETWEEN THE LINE OF SN SHOWERS AND THE
DEVELOPING STRONG INFLOW JET FORECAST TO FORM NEAR SERN NH. 12Z
MODEL GUIDANCE SHIFTED THIS AREA OF FORMATION SLIGHTLY SW FROM 00Z
MODEL SUITE. THIS BRINGS AREAS LIKE MHT AND ASH A LITTLE CLOSER TO
THE BRIEF HEAVY SNWFL THREAT. HRRR GUIDANCE...ALONG WITH
ARW...NMM...AND REGIONAL CMC ALL SHOW THE POTENTIAL FOR QPF...AND
THUS SNWFL...TO BRIEFLY BE HEAVY AS THIS INFLOW JET SWEEPS NEWD
THRU THE FORECAST AREA. SNWFL RATES MAY EXCEED 1 TO 3 INCHES PER
HOUR IN THE HEAVIEST SNWFL...THOUGH MAY ONLY LAST FOR AN HOUR OR
SO. MIXING ANY OF THAT WIND ALOFT DOWN IN HEAVY SHOWERS COULD ALSO
BRING 30 TO 35 MPH GUSTS...WHICH WOULD LEAD TO NEAR ZERO
VISIBILITY AT TIMES. I HAVE AN SPS IN EFFECT TO HIGHLIGHT THIS
SHORT DURATION...HEAVY SNWFL ASPECT OF THE SYSTEM. IN
ADDITION...LAPSE RATES ALOFT EXCEED 7 C/KM...SUFFICIENT FOR STRONG
WARM SEASON CONVECTION LET ALONE WINTER. WILL KEEP THUNDER IN THE
FORECAST FOR AREAS NEAR THE COAST WHERE THIS UNSTABLE AIR MASS IS
ABLE TO MOVE IN OFF THE WATER. ANY CONVECTION WILL FURTHER ENHANCE
THOSE SNWFL RATES.
S/WV TROF CONTINUES NEGATIVE TILT THRU THE AREA...AND BAND OF
SNWFL SHOULD BEGIN TO SLOW AND PIVOT AS IT APPROACHES CENTRAL ME.
HEAVIEST AMOUNTS WILL BE IN OUR ERN ZONES...GENERALLY FROM AUG
NEWD. AGAIN WILL HAVE TO MONITOR BOUNDARY LAYER TEMPS NEAR THE
COAST...AS MODELS CONTINUE TO SUGGEST WARMING MAKING IT WELL
INLAND. TEMPS ALOFT WOULD ARGUE THAT THIS STRUGGLES TO MAKE
PROGRESS MUCH PAST THE NECKS AND ISLANDS. CAPE ELIZABETH AND MAYBE
EVEN PWM MAY BE RA...WHILE THE TURNPIKE IS HEAVY SNWFL. HOWEVER
TOO MUCH UNCERTAINTY EXISTS TO CHANGE HEADLINES FROM WHERE WE HAVE
THEM CURRENTLY. SNWFL AMOUNTS LOOK VERY SIMILAR TO PREVIOUS
SHIFT...MAYBE SLIGHTLY HIGHER OVER SWRN ME. HOWEVER THESE STILL
FALL WITHIN ADVISORY RANGE. STILL A LOW CHANCE THAT SOME OF THE
ADVISORY MAY NEED TO BE CONVERTED TO WARNINGS AS THE BANDING SETS
UP.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/...
LOW PRES DEEPENS INTO THE 970S OVER THE CANADIAN MARITIMES
WED...SETTING UP A STRONG PRES GRADIENT ACROSS THE AREA. FLOW IN
CAA WILL BECOME GUSTY EARLY WED...INCREASING IN THE AFTERNOON AS
THE CORE OF WLY JET AROUND 5000 FEET MOVES OVERHEAD. BUFKIT
SOUNDINGS SHOW SOME POTENTIAL TO MIX DOWN SOME OF THIS JET...WITH
A FEW MODELS SHOWING GUSTS IN THE 40 TO 45 KT RANGE. GIVEN THAT A
WIND HEADLINE WOULD COMPLICATE AN ALREADY COMPLICATED FORECAST
EVEN FURTHER...WILL HOLD OFF FOR NOW AND ALLOW THE MIDNIGHT SHIFT
TO REASSESS.
UPSLOPE SN SHOWERS WILL LINGER OVER THE NRN ZONES IN WLY FLOW WED.
AN ADDITIONAL COUPLE OF INCHES IS POSSIBLE IN THE FAVORED AREAS.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
HIGH IMPACT WX: LOW CONFIDENCE FOR SIGNIFICANT SNOW CENTERED
AROUND SATURDAY.
THE 500 MB PATTERN CONTINUES TO BUILD WEAK TO MODERATE RIDGING
ACROSS THE WRN CONUS AND ERN PACIFIC...WITH A MEAN...BUT
FLUCTUATING TROUGH OVER THE ERN CONUS. ALL IN ALL THOUGH...SO
CALLED PINEAPPLE EXPRESS ACROSS THE PACIFIC WILL PROVIDE ENOUGH
WAVES TO CONTINUALLY KNOCK DOWN THE RIDGE IN THE WEST...AND LACK
OF COLD AIR OVER NOAM WILL LIMIT THERMAL ADVECTION ENOUGH IN THE
ARCTIC TO MINIMIZE WAVE PRODUCTION TO MAINTAIN SOLID TROUGH OVER
ERN CONUS. THIS...WILL SEE SOME CHANGEABLE CONDS THRU THE EXTENDED
WITH TEMPS FLUCTUATING SEVERAL DEGREES EITHER SIDE OF NORMAL.
SENSIBLE WX WILL SEE SFC RIDGE SLOWLY PASSING TO OUR S THU AND
FRI...WITH SFC LOW MOVING NE INTO THE GREAT LAKES FRI NIGHT. 500MB
WEAVE ROTATING AROUND THE BASE OF THE TROUGH WILL DEVELOP COASTAL
BY SAT MORNING WHICH TRACKS OFF NEW ENGLAND COAST SAT. THIS WILL
BE OUT NEXT PRECIP MAKER. MED RANGE MODELS IN BETTER AGREEMENT ON
TIMING...WITH PRECIP STARTING SOMETIME FRI NIGHT AND ENDING SAT
NIGHT. TRACK AND INTENSITY FORECASTS VARY QUITE A
BIT...PARTICULARLY WHERE P-TYPE AND INTENSITY ARE CONCERNED WITH
THE GFS MOVING THE LOW FURTHEREST OFFSHORE...WHILE THE GGEM IS THE
CLOSEST...WITH THE EURO IN THE MIDDLE. SO WHILE SOME PRECIP CAN BE
EXPECTED...AND IT WILL LIKELY BE SNOW INLAND...EVERYTHING ELSE
STILL REMAINS LOW CONFIDENCE. UPPER LVL LOW CROSSES THE REGION
SUNDAY WITH SHSN POSSIBLE...AND COLDER HIGH PRESSURE EXPECTED
EARLY NEXT WEEK.
&&
.AVIATION /01Z WEDNESDAY THROUGH SUNDAY/...
SHORT TERM...IFR CONDITIONS ARE STEADILY PROGRESSING INTO THE AREA
AS WAA INCREASES ALOFT. ONSHORE FLOW NEAR COASTAL ME WILL LEADING
TO SOME OCEAN EFFECT AND OCEAN ENHANCED SNWFL...MAINLY AFFECTING
PWM...AUG...AND RKD. IFR CONDITIONS AT LEB WILL EXPANDED EWD INTO
HIE...CON...MHT...AND EVENTUALLY PSM IN THE NEXT FEW HOURS.
CONFIDENCE IS LOW SO HAVE NOT INCLUDED IN THE TAFS...BUT A PERIOD
OF 1 INCH PER HOUR SNWFL RATES IS POSSIBLE FROM NEAR PSM...NEWD
THRU PWM...AUG...AND RKD. SLY WIND GUSTS OF 25 KTS MAY ACCOMPANY
THIS SNWFL. MOST LIKELY THIS HAPPENS BETWEEN 00Z AND 05Z. SNWFL
QUICKLY SWEEPS THRU THE AREA AND CONDITIONS IMPROVE FROM W TO E
AFTER 06Z. UPSLOPE SHSN LINGER AT HIE...AND INTERMITTENT IFR
CONDITIONS ARE POSSIBLE THERE. WLY WIND GUSTS OF 40 KTS ARE
POSSIBLE WED IN STRONG CAA.
LONG TERM...VFR WED NIGHT THROUGH FRI. FLIGHT RESTRICTIONS
EXPECTED LATE FRI NIGHT INTO SAT EVE IN SN...OR POSSIBLE RA NEAR
THE COAST. SOME IMPROVEMENT IS POSSIBLE ON SUN.
&&
.MARINE...
SHORT TERM...GALE WARNINGS REMAIN IN EFFECT FOR ALL WATERS THRU
WED. WINDS MAY GUST TO NEAR STORM FORCE FOR A TIME IN STRONG CAA
WED.
LONG TERM...WINDS GRADUALLY DIMINISH FROM GALES WED EVE...TO SCA
FOR THU....AND BELOW SCA THU NIGHT THRU FRI NIGHT. SCA OR GALES
POSSIBLE AGAIN SAT AND SAT NIGHT.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...WINTER WEATHER ADVISORY UNTIL 4 AM EST WEDNESDAY FOR MEZ007-
012-019-020.
WINTER STORM WARNING UNTIL 10 AM EST WEDNESDAY FOR MEZ008-009-
013-014-021-022-028.
WINTER WEATHER ADVISORY UNTIL 1 AM EST WEDNESDAY FOR MEZ018-
023-024.
WINTER WEATHER ADVISORY UNTIL 10 AM EST WEDNESDAY FOR
MEZ025>027.
NH...WINTER WEATHER ADVISORY UNTIL 4 AM EST WEDNESDAY FOR
NHZ001>004-006.
WINTER WEATHER ADVISORY UNTIL 1 AM EST WEDNESDAY FOR
NHZ008>010-012>014.
MARINE...GALE WARNING UNTIL 11 PM EST WEDNESDAY FOR ANZ150>154.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
634 PM EST TUE JAN 12 2016
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 429 PM EST TUE JAN 12 2016
WATER VAPOR IMAGERY AND RAP ANALYSIS CONTINUE A SHOW A TROF
EXTENDING FROM HUDSON BAY INTO THE GREAT LAKES REGION. IN THE WAKE
OF THE VIGOROUS SHORTWAVE THAT IS MOVING THRU THE LWR GREAT LAKES
ATTM...DRIER AIR...SUBSIDENCE AND FALLING INVERSION HEIGHTS (NOW
AROUND 5KFT W AND 7KFT E PER LATEST RAP) HAVE RESULTED IN SOME
DIMINISHING OF LES TODAY...THOUGH SOME MDT SNOW SHOWERS CONTINUE.
INVERSION HEIGHTS REMAIN RELATIVELY STEADY STATE TONIGHT...BUT THERE
ARE SOME AREAS OF CONCERN AS WINDS SLOW BACK. FIRST...OVER THE NE
FCST AREA...STRENGTHENING LAND BREEZES IN CONCERT WITH LARGER SCALE
BACKING WINDS OVER UPPER MI WILL LEAD TO INCREASING LOW-LEVEL
CONVERGENCE FROM ALGER COUNTY INTO NRN LUCE COUNTY. ALONG WITH THE
LONG FETCH...EXPECT 3-5 INCHES OF SNOW IN GENERAL FROM AROUND GRAND
MARAIS E ACROSS NRN LUCE COUNTY. SNOW WILL END IN WRN ALGER COUNTY
TONIGHT AS BANDS SHIFT E UNDER BACKING WINDS. MOST OF THE LES SHOULD
BE OFFSHORE BY SUNRISE...THOUGH SOME LES WILL BRUSH THE SHORELINE
FROM GRAND MARAIS EASTWARD IN THE MORNING. ALGER COUNTY LES ADVY HAS
BEEN EXTENDED TO 12Z WED WITH LUCE ADDED TO THAT.
TO THE W...A TYPICAL CONVERGENCE PATTERN WILL DEVELOP AS BACKING
WINDS AIDED BY LAND BREEZE RESULTS IN WSW WINDS DEVELOPING OVER THE
SRN PART OF WRN LAKE SUPERIOR. MEANWHILE...WINDS REMAIN MORE WNW
BTWN THE KEWEENAW AND ISLE ROYALE. END RESULT IS ENHANCED
CONVERGENCE SETTING UP ACROSS THE MID PORTION OF WRN LAKE
SUPERIOR...AIMED INTO THE FAR NRN PART OF ONTONAGON COUNTY AND INTO
CNTRL HOUGHTON COUNTY...ROUGHLY BTWN TWIN LAKES AND PAINESDALE. HIGH
RES MODEL GUIDANCE IS IN GOOD AGREEMENT ON THIS SCENARIO WITH ONLY
SUBTLE DIFFERENCES IN PLACEMENT OF HEAVIEST QPF. CONVERGENCE BAND
MAY SHIFT N SLIGHTLY DURING THE DAY WED AND AFFECT THE HOUGHTON
AREA. LES WILL BE LIGHT THIS EVENING AS FLOW ADJUSTS OVER WRN LAKE
SUPERIOR. LES SHOULD THEN INCREASE OVERNIGHT THRU WED IN THE
AFORMENTIONED AREA AS THE CONVERGENCE ZONE SETS UP. THERE IS SOME
INDICATION FOR A SLIGHT LIFTING OF THE INVERSION LATE TONIGHT/WED
AND LIFTING OF THE DGZ TO ENCOMPASS MORE OF THE CONVECTIVE
LAYER...ESPECIALLY WED. SO...GREATER SNOW ACCUMULATIONS WILL OCCUR
DURING THE DAY WED. EXPECT GENERALLY 2-4 INCHES OF SNOW
TONIGHT...THEN 3-7 INCHES OF SNOW WED. ADVY WILL ONLY BE CARRIED FOR
NRN HOUGHTON COUNTY WHERE BEST SNOWFALL IS EXPECTED. IF IT LATER
LOOKS LIKE MORE OF NRN ONTONAGON COUNTY MAY BE IMPACTED...ADVY WILL
NEED TO BE EXPANDED.
OTHER POTENTIAL CONCERN IS WIND CHILL HEADLINES IN THE COUNTIES
ALONG THE MI/WI BORDER. WITH MIN TEMPS CURRENTLY EXPECTED AROUND
-10F AND SUSTAINED WINDS LESS THAN 10 MPH...APPARENT TEMPS END UP
JUST SHY OF THE -25F THRESHOLD FOR WIND CHILL ADVY. WILL BE
SOMETHING TO MONITOR DURING THE EVENING IN THE EVENT TEMPS FALL MORE
THAN EXPECTED AND/OR WINDS ARE A BIT STRONGER.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 429 PM EST TUE JAN 12 2016
WARMER AIR WILL BE MOVING IN STARTING WEDNESDAY NIGHT. NW FLOW AND
AN ELONGATED SHORTWAVE WILL CONTINUE ALOFT WITH A 300MB JET AROUND
120KTS. THE FOCUS FOR ANY LINGERING MODERATE SNOW SHOWERS WILL BE
OVER THE NW FAVORED WIND SNOW BELTS OF THE KEWEENAW PENINSULA.
ELSEWHERE...MORE OF AN OFFSHORE OR PARALLEL SHORE FLOW IS
ANTICIPATED OVER THE E. ANOTHER 1-2IN OF SNOW WILL BE POSSIBLE FROM
THE PORCUPINE MTNS THROUGH THE TIP OF THE KEWEENAW...AND THEN RIGHT
ALONG THE SHORELINE FROM GRAND MARAIS TO WHITEFISH POINT.
THE 500MB LOW SPINNING OVER W HUDSON BAY WILL BEGIN TO SINK
OVER N MANITOBA. AS A RESULT...LOOK FOR A MORE W FLOW TO TAKE HOLD
OVER THE UPPER GREAT LAKES ON THURSDAY AS A TROUGH EXTENDS S FROM
THE 500MB LOW ALL THE WAY THROUGH THE CENTRAL PLAINS AND DOWN TROUGH
THE GULF OF MEXICO. SYNOPTIC SNOW/SNOW SHOWERS SHOULD WILL RETURN
THURSDAY...AHEAD OF THE COMBINING N LOWS SINKING ACROSS THE N AND
CENTRAL PLAINS. THERE HAS BEEN SOME DIFFERENCES ON THE TRACK OF THIS
LOW OVER THE PAST 24 HOURS. YESTERDAY THEY SHOWED MORE OF A S
TREND...LIKE THE 12Z SREF /OVER E KS/OK AT 06Z FRIDAY/. SINCE THEN
THEY ARE A BIT MORE N INTO IA. EITHER WAY...A PERSISTANT NE-N SFC
FLOW LOOKS TO SET IN ACROSS LAKE SUPERIOR AND UPPER MI FRIDAY
AFTERNOON THROUGH SATURDAY EVENING AS THE SFC LOW EXITS ACROSS THE
LOWER GREAT LAKES. THIS FEATURE LOOKS TO JOIN FORCES WITH ANOTHER
LOW DEEPENING AS IT TRACKS UP THE E SEABOARD SATURDAY. THE RESULT
WILL BE A STEADY TROUGH OVER OUR AREA WITH N-NW FLOW THROUGH TUESDAY
AS A SFC HIGH OVER THE PLAINS SUNDAY NIGHT SLOWLY ATTEMPS TO BUILD
IN OVER THE FIRST HALF OF THE WORK WEEK.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 622 PM EST TUE JAN 12 2016
AS WINDS CONTINUE TO BACK SLOWLY WEST THRU THE FCST PERIOD...LAKE
EFFECT SNOW SHOWERS WILL NOT AFFECT KSAW TONIGHT/WED MORNING...AND
DEVELOPING DOWNSLOPE COMPONENT TO THE WIND SHOULD ENSURE VFR
CONDITIONS CONTINUE TO PREVAIL. BACKING WINDS HAVE ALREADY SHIFTED
LAKE EFFECT SNOW SHOWERS OVER WRN UPPER MI. AT KIWD...BANDS HAVE
SHIFTED N OF THE TERMINAL THIS EVENING ALLOWING FOR VFR CONDITIONS TO
PREVAIL EARLY THIS EVENING BUT EXPECT MVFR CLOUDS TO MOVE BACK IN
LATER THIS EVENING AND REMAIN THROUGH FORECAST PERIOD. AT
KCMX...-SHSN WILL CONTINUE WITH A WIND TRAJECTORY OFF THE LAKE.
EXPECT IFR CONDITIONS TO MOSTLY PREVAIL...BUT AS IS TYPICAL FOR LAKE
EFFECT...CONDITIONS WILL BE VARIABLE WITH SOME MVFR AND LIFR AT
TIMES. &&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 404 PM EST TUE JAN 12 2016
WINDS WILL RELAX TONIGHT...AND REMAIN UNDER 25KTS THROUGH THROUGH
THURSDAY NIGHT /DOWN TO LESS THAN 15KTS FOR MUCH OF LAKE SUPERIOR
LATE WEDNESDAY NIGHT THROUGH THURSDAY/. HOWEVER...THERE COULD STILL
BE SOME HEAVY FREEZING SPRAY OVER THE E HALF OF LAKE SUPERIOR EARLY
THIS EVENING. LOW PRESSURE ALONG THE S ONTARIO AND QUEBEC BORDER
WILL EXIT NE OF MAINE OVERNIGHT. A TROUGH WILL LINGER OVER LAKE
SUPERIOR AS A RIDGE ACROSS MINNESOTA THIS EVENING SLIDES ACROSS WI
OVERNIGHT...AND THEN TO THE SE STATES WEDNESDAY. EXPECT THE TROUGH
OVER LAKE SUPERIOR TO DEEPEN WEDNESDAY INTO THURSDAY.
TWO AREAS OF LOW PRESSURE OVER N MANITOBA AND THE DAKOTAS THURSDAY
MORNING ARE EXPECTED TO COMBINE AND SHIFT ACROSS THE CENTRAL PLAINS
THURSDAY NIGHT-FRIDAY. NE GUSTS OF 25-30KTS WILL RETURN FRIDAY
AFTERNOON...AND LINGER THROUGH MUCH OF THE PERIOD WHILE TURNING MORE
OUT OF THE N-NNW /ESPECIALLY OVER THE E HALF OF LAKE SUPERIOR/.
THE LOW WILL LIFT NE ACROSS LOWER MI FRIDAY NIGHT AND EXIT
ACROSS N NY SATURDAY NIGHT AS A STRONGER LOW RIDES UP THE E
SEABOARD. LOOK FOR THE LINGERING RIDGE TO WEAKEN ACROSS LAKE
SUPERIOR AS A HIGH PRESSURE SYSTEM MOVES FROM CANADA TO THE N AND
CENTRAL PLAINS SUNDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST WEDNESDAY FOR MIZ003.
LAKE EFFECT SNOW ADVISORY UNTIL 7 AM EST WEDNESDAY FOR MIZ006-
007.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING UNTIL 9 PM EST THIS EVENING FOR
LSZ249>251-266-267.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...KF
AVIATION...VOSS
MARINE...KF
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 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
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 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 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
938 PM CST TUE JAN 12 2016
.UPDATE...
ISSUED AT 929 PM CST TUE JAN 12 2016
SOME LIGHT ECHOS ON RADAR ARE STARTING TO SHOW UP OVER FAR NORTH
CENTRAL NORTH DAKOTA. FOR LATE EVENING UPDATE HAVE ADDRESSED THIS
BY STARTING LOW CHANCES FOR SNOW NOW...WHICH IS A BIT EARLIER THAN
PREVIOUS FORECAST. OTHERWISE...BESIDES ADJUSTING CLOUD COVER
TOWARDS CURRENT SATELLITE TRENDS REMAINDER OF FORECAST WAS IN GOOD
SHAPE.
UPDATE ISSUED AT 604 PM CST TUE JAN 12 2016
FOR EARLY EVENING UPDATE HAVE ADDED LOW CHANCES FOR SNOW OVER THE
FAR SOUTHWEST AS WEAK WAVE MOVES THROUGH AND SOME WEAK ECHOS ARE
SHOWING UP ON THE BOWMAN NDARB RADAR. ONLY OTHER CHANGE WAS TO
INCREASE CLOUD COVER THROUGH THE EVENING AS SATELLITE HAS MOST OF
THE AREA UNDER OVERCAST SKIES.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 245 PM CST TUE JAN 12 2016
LOW-END PRECIPITATION CHANCES AND A STARK TEMPERATURE CONTRAST
FROM NORTH CENTRAL TO SOUTHWEST ND HIGHLIGHT THE SHORT TERM.
LIGHT SNOW FROM NORTHWEST INTO SOUTH CENTRAL ND HAS BEEN ON A
STEADY WEAKENING TREND SINCE ABOUT 19 UTC...AND IS EXPECTED TO
DIMINISH FURTHER BY LATE AFTERNOON AS ASCENT DROPS OFF. WE ARE
THEN CARRYING ANOTHER SLIGHT CHANCE OF LIGHT SNOW LATE TONIGHT
FROM BOTTINEAU TOWARD RUGBY AND ROLLA OUT OF RESPECT TO A WEAK
SHORTWAVE TROUGH IN NORTHWEST FLOW ALOFT THAT WILL CLIP THAT
AREA AFTER 06 UTC.
INTERESTINGLY...BOTH THE OPERATIONAL AND EXPERIMENTAL /ESRL-RUN/
HRRR FLAVORS HAVE BEEN SIMULATING DENSE FOG DEVELOPMENT ACROSS
CENTRAL ND TONIGHT. THEY ARE ON THEIR OWN IN THIS EXPECTATION AS
NEITHER THE 12 UTC NAM-NEST OR POINT-BASED MOS GUIDANCE /MAV OR
MET OUTPUT/ SUGGEST THIS SCENARIO. CLOSER INSPECTION SHOWED THE
HRRR SIMULATIONS DEVELOP THIS FOG OVER LAKE SAKAKAWEA AND THEN
ADVECT IT DOWNSTREAM ON LIGHT WIND FIELDS. SKIN TEMPERATURES IN
THE HRRR SIMULATIONS ARE ABOVE 40 F OVER LAKE SAKAKAWEA...WHICH
MEANS THEY ARE ASSUMING MUCH MORE OPEN WATER EXISTS THAN DOES IN
REALITY. THUS...WE BELIEVE THAT THE HRRR GUIDANCE IS LIKELY
OVERZEALOUS WITH ITS EXPECTATION OF FOG AND LOW CLOUD FORMATION.
ON WEDNESDAY...STRONGER MID-LEVEL WARM AIR ADVECTION WILL OCCUR
AND PUSH 850-MB TEMPERATURES TO +2 TO +4 C SOUTH AND WEST OF THE
MISSOURI RIVER BY AFTERNOON. THE RESULT WILL BE HIGHS ABOVE 32 F
IN THOSE AREAS...CONTRASTED BY HIGHS ONLY IN THE TEENS F ACROSS
ROLETTE COUNTY. THE LOW- TO MID-LEVEL WARM FRONTAL BOUNDARY THAT
WILL SEPARATE THOSE AIR MASSES COULD SERVE AS A FOCUS FOR LIGHT
PRECIPITATION BY LATE DAY AS ANOTHER SHORTWAVE TROUGH APPROACHES
THE AREA. THE 12 UTC MULTI-MODEL CONSENSUS SUPPORTED POPS OF 20
TO 30 PERCENT OVER NORTHWEST ND BY LATE AFTERNOON...AND WE CHOSE
TO CONTINUE WITH A SLIGHT CHANCE OF LIGHT FREEZING IN THE WATFORD
CITY AND WILLISTON AREAS BASED ON EXPECTED TEMPERATURES ALOFT. WE
KEPT THE FORECAST DRY OVER SOUTH CENTRAL ND GIVEN A DRY BOUNDARY
LAYER...BUT THE 12 UTC NCEP WRF-ARW SIMULATED LIGHT PRECIPITATION
INTO THE BISMARCK AREA BY VERY LATE AFTERNOON...WHICH REPRESENTS
A VERY LOW-END...BUT NON-ZERO RISK OF LIGHT FREEZING RAIN. WE DID
NOT INCLUDE THAT IN THE OFFICIAL FORECAST AT THIS POINT FOR THAT
AREA THOUGH SINCE THE PROBABILITY OF OCCURRENCE IS VERY LOW.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 207 PM CST TUE JAN 12 2016
THE MAIN ISSUES IN THE LONG TERM ARE SNOW CHANCES FOR THE END OF
THE WEEK AND DANGEROUS COLD THIS WEEKEND.
A CLIPPER WILL APPROACH NORTH DAKOTA WEDNESDAY EVENING.
PRECIPITATION IS EXPECTED TO FORM ACROSS A PERSISTENT BAROCLINIC
ZONE BISECTING NORTH DAKOTA. THE 12 UTC MODELS ARE IN FAIRLY GOOD
AGREEMENT IN SPREADING 1 TO 2 INCHES OF SNOW ACROSS NORTHERN NORTH
DAKOTA...WITH THE HIGHEST AMOUNTS CONFINED TO THE TURTLE
MOUNTAINS. LIGHT SNOW IS EXPECTED TO BEGIN ACROSS FAR NORTHWEST
NORTH DAKOTA WEDNESDAY EVENING AND SPREAD SOUTHEAST THROUGH
WEDNESDAY NIGHT INTO THURSDAY MORNING. THE BAROCLINIC ZONE WILL
SHIFT FURTHER SOUTHWEST THURSDAY AND FRIDAY...AND THEREFORE SNOW
CHANCES WILL ALSO SHIFT FROM NORTHERN NORTH DAKOTA TO SOUTHWEST
NORTH DAKOTA. HOWEVER...WITH THESE QUICK MOVING WAVES ONLY LIGHT
QPF AMOUNTS ARE EXPECTED...SO LITTLE TO NO IMPACTS ARE
ANTICIPATED.
ANOTHER DEEP GREAT LAKES TROUGH IS EXPECTED TO FORM BY THIS
WEEKEND. THIS WILL ALLOW BITTERLY COLD ARCTIC AIR TO PUSH INTO
NORTH DAKOTA. THERE IS SOME UNCERTAINTY AS TO EXACTLY WHEN THE
SURFACE HIGH AND COLDEST AIR WILL SETTLE ACROSS NORTH DAKOTA.
HOWEVER...IT APPEARS TEMPERATURES WELL BELOW ZERO ARE
LIKELY...WITH WIND CHILLS POTENTIALLY REACHING THE 20S AND 30S
BELOW.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 604 PM CST TUE JAN 12 2016
AREAS OF MVFR CIGS WILL CONTINUE THROUGH EARLY EVENING OVER
CENTRAL AND WESTERN NORTH DAKOTA...THOUGH ARE EXPECTED TO IMPROVE
TO VFR BY LATER TONIGHT INTO WEDNESDAY MORNING. THE ONLY
EXCEPTION WILL BE OVER PORTIONS OF NORTH CENTRAL NORTH DAKOTA
WHERE AREAS OF MVFR CIGS MAY LINGER INTO WEDNESDAY MORNING AS -SN
MAY DEVELOP. LATER WEDNESDAY AFTERNOON...LCL MVFR CIGS/VIS MAY
OCCUR OVER NORTHWEST NORTH DAKOTA WITH SOME LIGHT SNOW AND
POSSIBLY A BIT OF FREEZING RAIN DEVELOPING.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JJS
SHORT TERM...CJS
LONG TERM...AJ
AVIATION...JJS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
621 PM CST TUE JAN 12 2016
.UPDATE...
ISSUED AT 604 PM CST TUE JAN 12 2016
FOR EARLY EVENING UPDATE HAVE ADDED LOW CHANCES FOR SNOW OVER THE
FAR SOUTHWEST AS WEAK WAVE MOVES THROUGH AND SOME WEAK ECHOS ARE
SHOWING UP ON THE BOWMAN NDARB RADAR. ONLY OTHER CHANGE WAS TO
INCREASE CLOUD COVER THROUGH THE EVENING AS SATELLITE HAS MOST OF
THE AREA UNDER OVERCAST SKIES.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 245 PM CST TUE JAN 12 2016
LOW-END PRECIPITATION CHANCES AND A STARK TEMPERATURE CONTRAST
FROM NORTH CENTRAL TO SOUTHWEST ND HIGHLIGHT THE SHORT TERM.
LIGHT SNOW FROM NORTHWEST INTO SOUTH CENTRAL ND HAS BEEN ON A
STEADY WEAKENING TREND SINCE ABOUT 19 UTC...AND IS EXPECTED TO
DIMINISH FURTHER BY LATE AFTERNOON AS ASCENT DROPS OFF. WE ARE
THEN CARRYING ANOTHER SLIGHT CHANCE OF LIGHT SNOW LATE TONIGHT
FROM BOTTINEAU TOWARD RUGBY AND ROLLA OUT OF RESPECT TO A WEAK
SHORTWAVE TROUGH IN NORTHWEST FLOW ALOFT THAT WILL CLIP THAT
AREA AFTER 06 UTC.
INTERESTINGLY...BOTH THE OPERATIONAL AND EXPERIMENTAL /ESRL-RUN/
HRRR FLAVORS HAVE BEEN SIMULATING DENSE FOG DEVELOPMENT ACROSS
CENTRAL ND TONIGHT. THEY ARE ON THEIR OWN IN THIS EXPECTATION AS
NEITHER THE 12 UTC NAM-NEST OR POINT-BASED MOS GUIDANCE /MAV OR
MET OUTPUT/ SUGGEST THIS SCENARIO. CLOSER INSPECTION SHOWED THE
HRRR SIMULATIONS DEVELOP THIS FOG OVER LAKE SAKAKAWEA AND THEN
ADVECT IT DOWNSTREAM ON LIGHT WIND FIELDS. SKIN TEMPERATURES IN
THE HRRR SIMULATIONS ARE ABOVE 40 F OVER LAKE SAKAKAWEA...WHICH
MEANS THEY ARE ASSUMING MUCH MORE OPEN WATER EXISTS THAN DOES IN
REALITY. THUS...WE BELIEVE THAT THE HRRR GUIDANCE IS LIKELY
OVERZEALOUS WITH ITS EXPECTATION OF FOG AND LOW CLOUD FORMATION.
ON WEDNESDAY...STRONGER MID-LEVEL WARM AIR ADVECTION WILL OCCUR
AND PUSH 850-MB TEMPERATURES TO +2 TO +4 C SOUTH AND WEST OF THE
MISSOURI RIVER BY AFTERNOON. THE RESULT WILL BE HIGHS ABOVE 32 F
IN THOSE AREAS...CONTRASTED BY HIGHS ONLY IN THE TEENS F ACROSS
ROLETTE COUNTY. THE LOW- TO MID-LEVEL WARM FRONTAL BOUNDARY THAT
WILL SEPARATE THOSE AIR MASSES COULD SERVE AS A FOCUS FOR LIGHT
PRECIPITATION BY LATE DAY AS ANOTHER SHORTWAVE TROUGH APPROACHES
THE AREA. THE 12 UTC MULTI-MODEL CONSENSUS SUPPORTED POPS OF 20
TO 30 PERCENT OVER NORTHWEST ND BY LATE AFTERNOON...AND WE CHOSE
TO CONTINUE WITH A SLIGHT CHANCE OF LIGHT FREEZING IN THE WATFORD
CITY AND WILLISTON AREAS BASED ON EXPECTED TEMPERATURES ALOFT. WE
KEPT THE FORECAST DRY OVER SOUTH CENTRAL ND GIVEN A DRY BOUNDARY
LAYER...BUT THE 12 UTC NCEP WRF-ARW SIMULATED LIGHT PRECIPITATION
INTO THE BISMARCK AREA BY VERY LATE AFTERNOON...WHICH REPRESENTS
A VERY LOW-END...BUT NON-ZERO RISK OF LIGHT FREEZING RAIN. WE DID
NOT INCLUDE THAT IN THE OFFICIAL FORECAST AT THIS POINT FOR THAT
AREA THOUGH SINCE THE PROBABILITY OF OCCURRENCE IS VERY LOW.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 207 PM CST TUE JAN 12 2016
THE MAIN ISSUES IN THE LONG TERM ARE SNOW CHANCES FOR THE END OF
THE WEEK AND DANGEROUS COLD THIS WEEKEND.
A CLIPPER WILL APPROACH NORTH DAKOTA WEDNESDAY EVENING.
PRECIPITATION IS EXPECTED TO FORM ACROSS A PERSISTENT BAROCLINIC
ZONE BISECTING NORTH DAKOTA. THE 12 UTC MODELS ARE IN FAIRLY GOOD
AGREEMENT IN SPREADING 1 TO 2 INCHES OF SNOW ACROSS NORTHERN NORTH
DAKOTA...WITH THE HIGHEST AMOUNTS CONFINED TO THE TURTLE
MOUNTAINS. LIGHT SNOW IS EXPECTED TO BEGIN ACROSS FAR NORTHWEST
NORTH DAKOTA WEDNESDAY EVENING AND SPREAD SOUTHEAST THROUGH
WEDNESDAY NIGHT INTO THURSDAY MORNING. THE BAROCLINIC ZONE WILL
SHIFT FURTHER SOUTHWEST THURSDAY AND FRIDAY...AND THEREFORE SNOW
CHANCES WILL ALSO SHIFT FROM NORTHERN NORTH DAKOTA TO SOUTHWEST
NORTH DAKOTA. HOWEVER...WITH THESE QUICK MOVING WAVES ONLY LIGHT
QPF AMOUNTS ARE EXPECTED...SO LITTLE TO NO IMPACTS ARE
ANTICIPATED.
ANOTHER DEEP GREAT LAKES TROUGH IS EXPECTED TO FORM BY THIS
WEEKEND. THIS WILL ALLOW BITTERLY COLD ARCTIC AIR TO PUSH INTO
NORTH DAKOTA. THERE IS SOME UNCERTAINTY AS TO EXACTLY WHEN THE
SURFACE HIGH AND COLDEST AIR WILL SETTLE ACROSS NORTH DAKOTA.
HOWEVER...IT APPEARS TEMPERATURES WELL BELOW ZERO ARE
LIKELY...WITH WIND CHILLS POTENTIALLY REACHING THE 20S AND 30S
BELOW.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 604 PM CST TUE JAN 12 2016
AREAS OF MVFR CIGS WILL CONTINUE THROUGH EARLY EVENING OVER
CENTRAL AND WESTERN NORTH DAKOTA...THOUGH ARE EXPECTED TO IMPROVE
TO VFR BY LATER TONIGHT INTO WEDNESDAY MORNING. THE ONLY
EXCEPTION WILL BE OVER PORTIONS OF NORTH CENTRAL NORTH DAKOTA
WHERE AREAS OF MVFR CIGS MAY LINGER INTO WEDNESDAY MORNING AS -SN
MAY DEVELOP. LATER WEDNESDAY AFTERNOON...LCL MVFR CIGS/VIS MAY
OCCUR OVER NORTHWEST NORTH DAKOTA WITH SOME LIGHT SNOW AND
POSSIBLY A BIT OF FREEZING RAIN DEVELOPING.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JJS
SHORT TERM...CJS
LONG TERM...AJ
AVIATION...JJS
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 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 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
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
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...UPDATED
NWS AUSTIN/SAN ANTONIO TX
930 PM CST TUE JAN 12 2016
.UPDATE...
A CLUSTER OF UPPER LEVEL CLOUDS AHEAD OF THE NEXT UPPER LEVEL
SYSTEM FORECAST TO AFFECT THE AREA WILL KEEP OVERNIGHT LOWS A BIT
WARMER THAN PREVIOUS NIGHTS. THESE UPPER LEVEL CLOUDS WILL REMAIN
ACROSS THE AREA ON WEDNESDAY WHILE LOW LEVEL MOISTURE INCREASES
AHEAD OF A PACIFIC FRONT. WEDNESDAYS HIGH TEMPERATURES ARE
EXPECTED TO REACH THE MID 60S OVER MOST LOCATIONS. RAIN CHANCES
ARE IN STORE FOR AREAS MAINLY ALONG AND EAST OF INTERSTATE 35 ON
THURSDAY AS THE UPPER LEVEL LOW AND PACIFIC FRONT PUSHES OVER THE
AREA. DRY WEATHER CONDITIONS ARE EXPECTED ON FRIDAY WITH RAIN
CHANCES RETURNING ON SATURDAY ACROSS THE EAST AS ANOTHER PACIFIC
FRONT PUSHES OVER THE AREA.
&&
.PREV DISCUSSION... /ISSUED 550 PM CST TUE JAN 12 2016/
AVIATION.../00Z TAF CYCLE/
SKC VFR PREVAILS OVER THE REGION WITH ONLY SOME HIGH SCT250 CIRRUS
POISED TO FILTER OVER THE REGION OVERNIGHT FROM THE SOUTHWEST.
WINDS ARE LIGHT AND VARIABLE AT 5 KT OR LESS AND WILL REMAIN SO
THROUGH 12Z. ONE ASPECT THAT WILL NEED TO BE WATCHED WITH BE
SHALLOW GROUND FOG AND/OR ISOLATED PATCHY IFR CIGS NEAR 12-15Z.
HAVE PLACED 5SM BR FOR NOW TO HEDGE THIS DIRECTION BUT BUFR
SOUNDINGS AND TIME-HEIGHTS OF THE HRRR INDICATE VERY LOW-LVL
SATURATION THAT COULD RESULT IN BRIEF LOWER RESTRICTIONS. WILL
MONITOR THESE TRENDS INTO THE 06Z TAF CYCLE. OTHERWISE...VFR IS
EXPECTED TO PREVAIL WEDNESDAY.
PREV DISCUSSION... /ISSUED 306 PM CST TUE JAN 12 2016/
SHORT TERM (TONIGHT THROUGH WEDNESDAY NIGHT)...
A GRADUAL INCREASE IN MOISTURE IS EXPECTED TONIGHT AND WEDNESDAY
AS SOUTHERLY FLOW IN THE LOW-LEVELS DEVELOPS. THE SOUTHERLY FLOW
SHOULD ALLOW FOR A LITTLE MILDER OVERNIGHT LOWS TONIGHT.
HOWEVER...CAN/T RULE OUT A FEW SPOTS DROPPING TO NEAR FREEZING
ACROSS THE WESTERN HILL COUNTRY. RAIN CHANCES RETURN TO THE RIO
GRANDE PLAINS SOUTH OF EAGLE PASS AND MOST OF THE COASTAL PLAINS
WEDNESDAY NIGHT AS AN UPPER TROUGH APPROACHES FROM THE WEST. ONLY
LIGHT AMOUNTS ARE EXPECTED AND WE/LL KEEP RAIN CHANCES IN THE
SLIGHT CHANCE CATEGORY (20%) FOR NOW AS DEEP LAYER MOISTURE AND
LIFT WILL BE LACKING.
LONG TERM (THURSDAY THROUGH TUESDAY)...
RAIN CHANCES CONTINUE ON THURSDAY FOR AREAS ALONG AND EAST OF I-35
AS THE ABOVE MENTIONED UPPER LEVEL TROUGH MOVES ACROSS SOUTHERN
TEXAS. WE/LL ALSO CONTINUE TO MENTION THE CHANCE FOR ISOLATED
THUNDERSTORMS EAST OF A TAYLOR TO FLORESVILLE LINE WITH SOME
MEAGER ELEVATED INSTABILITY MOVING IN WITH THE UPPER TROUGH. THE
UPPER TROUGH AXIS MOVES TO OUR EAST THURSDAY NIGHT...BRINGING AN
END TO RAIN CHANCES. A PACIFIC COLD FRONT WILL ALSO BEGIN TO MOVE
THROUGH THE REGION THURSDAY NIGHT BRINGING MUCH DRIER AIR TO SOUTH
CENTRAL TEXAS. DRY WEATHER IS ANTICIPATED FOR ALL AREAS ON FRIDAY
BEFORE ANOTHER COLD FRONT MOVES THROUGH SATURDAY AFTERNOON. THE
COLD FRONT ON SATURDAY WILL ALSO BE ACCOMPANIED BY A FAIRLY
COMPACT AND FAST MOVING UPPER TROUGH. THIS WILL LIKELY LEAD TO
WINDY CONDITIONS ACROSS THE REGION ON SATURDAY. MOISTURE RETURN
AHEAD OF THIS FRONT WILL BE LACKING AND FOR NOW... WE/LL ONLY
MENTION A SLIGHT CHANCE FOR SHOWERS EAST OF A GEORGETOWN TO KARNES
CITY LINE. THE MEDIUM RANGE MODELS CONTINUE TO SHOW SOME
DISAGREEMENT WITH THE WEATHER PATTERN EARLY NEXT WEEK. IT DOES
APPEAR THAT WE/LL BE A LITTLE DRIER THAN PREVIOUS MODELS INDICATED
AS MOISTURE RETURN AHEAD OF THE NEXT COLD FRONT WILL BE LACKING.
WE/LL KEEP A LOW CHANCE FOR SHOWERS EAST OF I-35 AND GO WITH A DRY
FORECAST ELSEWHERE.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 41 64 47 65 47 / 0 0 10 20 10
AUSTIN BERGSTROM INTL AIRPORT 36 63 44 65 45 / 0 0 20 20 10
NEW BRAUNFELS MUNI AIRPORT 38 63 46 66 45 / 0 0 20 20 10
BURNET MUNI AIRPORT 38 63 43 64 44 / 0 0 - 10 -
DEL RIO INTL AIRPORT 40 63 44 67 43 / 0 0 - 0 0
GEORGETOWN MUNI AIRPORT 37 63 44 65 46 / 0 0 - 20 10
HONDO MUNI AIRPORT 38 63 45 66 43 / 0 0 10 10 0
SAN MARCOS MUNI AIRPORT 38 63 45 65 46 / 0 0 20 20 10
LA GRANGE - FAYETTE REGIONAL 40 64 48 66 50 / 0 0 20 40 10
SAN ANTONIO INTL AIRPORT 40 63 47 65 47 / 0 0 20 20 -
STINSON MUNI AIRPORT 41 63 48 65 46 / 0 0 20 20 -
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...17
SYNOPTIC/GRIDS...ALLEN
PUBLIC SERVICE/DATA COLLECTION...30
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
818 PM CST TUE JAN 12 2016
.DISCUSSION...
CLEAR SKIES AND LIGHT WINDS COUPLED WITH A SUBTLE INCREASE IN LOW
LEVEL MOISTURE SHOULD ALLOW FOR SOME FOG FORMATION OVERNIGHT. THE
HRRR AND RAP ARE BOTH VERY AGGRESSIVE WITH FOG DEVELOPMENT OVER
THE SW ZONES LATER TONIGHT. THE SREF ENSEMBLES CONSIDERABLY LESS
BULLISH WITH FOG THREAT. 00Z SOUNDINGS FROM CRP AND LCH DON`T LOOK
TERRIBLY FAVORABLE EITHER BUT WILL ADD PATCHY FOG TO THE GRIDS
AND MENTION LOCALLY DENSE TO THE SW ZONES FOR LATE TONGIHT. IF THE
HRRR/RAP ARE CORRECT...A DENSE FOG ADVISORY MAY BE REQUIRED LATER
TONGIHT FOR AREAS SW OF HOUSTON. BUMPED MIN TEMPS UP A DEGREE OR
TWO IN A FEW SPOTS AND LOWER ALONG THE IMMEDIATE COAST. 43
&&
.PREV DISCUSSION... /ISSUED 506 PM CST TUE JAN 12 2016/
AVIATION...
OTHER THAN A PERIOD OF PATCHY GROUND FOG...VFR EXPECTED. THE TIME
FRAME WHEN PATCHY GROUND FOG WILL BE MOST PREVALENT WILL BE FROM
10Z TO 15Z. LBX MAY SEE FOG FROM 08Z TO 15Z. DURING THE DAY ON
WEDNESDAY SURFACE WINDS SHOULD BECOME SOUTHEAST.
40
PREV DISCUSSION... /ISSUED 253 PM CST TUE JAN 12 2016/
DISCUSSION...
MODELS SHOW A PROGRESSIVE PATTERN THIS FORECAST PERIOD WITH A
SEQUENCE OF SHORT WAVE DISTURBANCES CROSSING THE AREA EVERY FEW
DAYS. FIRST DISTURBANCE TO CROSS THE AREA THURSDAY WITH ANOTHER
STRONGER DISTURBANCE COMING DOWN IN NW UPPER FLOW ON SATURDAY. YET
ANOTHER UPPER DISTURBANCE PROGGED TO CROSS THE AREA SUNDAY NIGHT
OR MONDAY. THERE WILL BE A CHANCE OF SHOWERS WITH EACH OF THESE
SYSTEMS.
SMALL CHANCE OF SEVERE WITH EACH DISTURBANCE WITH COLD
AIR ALOFT...SUGGESTING HAIL...AND STRONG WIND FIELDS SUGGESTING
DAMAGING WIND THREAT. MISSING INGREDIENT WOULD APPEAR TO BE
LIMITED MOISTURE RETURN AND INSTABILITY. LIMITED MOISTURE AND
SPEED OF SYSTEMS ALSO A LIMITING FACTOR IN RAINFALL POTENTIAL. STILL
SOMETHING THAT WILL NEED TO BE WATCHED. SATURDAY SYSTEM LOOKS
QUITE STRONG WITH OR WITHOUT THUNDERSTORMS. GFS DETERMINISTIC
WINDS OVER THE COASTAL AND MARINE AREAS ACTUALLY GALE FORCE
SATURDAY NIGHT...ECMWF NOT QUITE AS STRONG. AGAIN SOMETHING THAT
WILL NEED TO BE WATCHED. 46
MARINE...
GENERALLY LIGHT EAST WINDS WILL PREVAIL THESE NEXT COUPLE OF DAYS
AS HIGH PRESSURE LINGERS OVER THE REGION. NO REAL CHANGES WITH THE
PAT- TERN UNTIL FRI WITH THE PASSAGE OF A WEAK COLD FRONT.
OFFSHORE WINDS WILL BE BRIEF WITH THIS BOUNDARY...BUT SHOULD BE
STRONGER WITH A SE- COND STRONG COLD FRONT ON SAT. AT LEAST ADVISORY
FLAGS ARE A GOOD POSSIBILITY STARTING SAT NIGHT/SUN IN THE WAKE OF
THIS FRONT...GALES NOT OUT OF QUESTION. 41
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 40 63 48 64 49 / 0 10 10 30 10
HOUSTON (IAH) 41 63 49 66 50 / 0 10 10 40 20
GALVESTON (GLS) 47 62 55 62 54 / 0 10 20 50 20
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...43
AREA FORECAST DISCUSSION...UPDATED
NWS AUSTIN/SAN ANTONIO TX
550 PM CST TUE JAN 12 2016
.AVIATION.../00Z TAF CYCLE/
SKC VFR PREVAILS OVER THE REGION WITH ONLY SOME HIGH SCT250 CIRRUS
POISED TO FILTER OVER THE REGION OVERNIGHT FROM THE SOUTHWEST.
WINDS ARE LIGHT AND VARIABLE AT 5 KT OR LESS AND WILL REMAIN SO
THROUGH 12Z. ONE ASPECT THAT WILL NEED TO BE WATCHED WITH BE
SHALLOW GROUND FOG AND/OR ISOLATED PATCHY IFR CIGS NEAR 12-15Z.
HAVE PLACED 5SM BR FOR NOW TO HEDGE THIS DIRECTION BUT BUFR
SOUNDINGS AND TIME-HEIGHTS OF THE HRRR INDICATE VERY LOW-LVL
SATURATION THAT COULD RESULT IN BRIEF LOWER RESTRICTIONS. WILL
MONITOR THESE TRENDS INTO THE 06Z TAF CYCLE. OTHERWISE...VFR IS
EXPECTED TO PREVAIL WEDNESDAY.
&&
.PREV DISCUSSION... /ISSUED 306 PM CST TUE JAN 12 2016/
SHORT TERM (TONIGHT THROUGH WEDNESDAY NIGHT)...
A GRADUAL INCREASE IN MOISTURE IS EXPECTED TONIGHT AND WEDNESDAY
AS SOUTHERLY FLOW IN THE LOW-LEVELS DEVELOPS. THE SOUTHERLY FLOW
SHOULD ALLOW FOR A LITTLE MILDER OVERNIGHT LOWS TONIGHT.
HOWEVER...CAN/T RULE OUT A FEW SPOTS DROPPING TO NEAR FREEZING
ACROSS THE WESTERN HILL COUNTRY. RAIN CHANCES RETURN TO THE RIO
GRANDE PLAINS SOUTH OF EAGLE PASS AND MOST OF THE COASTAL PLAINS
WEDNESDAY NIGHT AS AN UPPER TROUGH APPROACHES FROM THE WEST. ONLY
LIGHT AMOUNTS ARE EXPECTED AND WE/LL KEEP RAIN CHANCES IN THE
SLIGHT CHANCE CATEGORY (20%) FOR NOW AS DEEP LAYER MOISTURE AND
LIFT WILL BE LACKING.
LONG TERM (THURSDAY THROUGH TUESDAY)...
RAIN CHANCES CONTINUE ON THURSDAY FOR AREAS ALONG AND EAST OF I-35
AS THE ABOVE MENTIONED UPPER LEVEL TROUGH MOVES ACROSS SOUTHERN
TEXAS. WE/LL ALSO CONTINUE TO MENTION THE CHANCE FOR ISOLATED
THUNDERSTORMS EAST OF A TAYLOR TO FLORESVILLE LINE WITH SOME
MEAGER ELEVATED INSTABILITY MOVING IN WITH THE UPPER TROUGH. THE
UPPER TROUGH AXIS MOVES TO OUR EAST THURSDAY NIGHT...BRINGING AN
END TO RAIN CHANCES. A PACIFIC COLD FRONT WILL ALSO BEGIN TO MOVE
THROUGH THE REGION THURSDAY NIGHT BRINGING MUCH DRIER AIR TO SOUTH
CENTRAL TEXAS. DRY WEATHER IS ANTICIPATED FOR ALL AREAS ON FRIDAY
BEFORE ANOTHER COLD FRONT MOVES THROUGH SATURDAY AFTERNOON. THE
COLD FRONT ON SATURDAY WILL ALSO BE ACCOMPANIED BY A FAIRLY
COMPACT AND FAST MOVING UPPER TROUGH. THIS WILL LIKELY LEAD TO
WINDY CONDITIONS ACROSS THE REGION ON SATURDAY. MOISTURE RETURN
AHEAD OF THIS FRONT WILL BE LACKING AND FOR NOW... WE/LL ONLY
MENTION A SLIGHT CHANCE FOR SHOWERS EAST OF A GEORGETOWN TO KARNES
CITY LINE. THE MEDIUM RANGE MODELS CONTINUE TO SHOW SOME
DISAGREEMENT WITH THE WEATHER PATTERN EARLY NEXT WEEK. IT DOES
APPEAR THAT WE/LL BE A LITTLE DRIER THAN PREVIOUS MODELS INDICATED
AS MOISTURE RETURN AHEAD OF THE NEXT COLD FRONT WILL BE LACKING.
WE/LL KEEP A LOW CHANCE FOR SHOWERS EAST OF I-35 AND GO WITH A DRY
FORECAST ELSEWHERE.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 41 64 47 65 47 / 0 0 10 20 10
AUSTIN BERGSTROM INTL AIRPORT 36 63 44 65 45 / 0 0 20 20 10
NEW BRAUNFELS MUNI AIRPORT 38 63 46 66 45 / 0 0 20 20 10
BURNET MUNI AIRPORT 38 63 43 64 44 / 0 0 - 10 -
DEL RIO INTL AIRPORT 40 63 44 67 43 / 0 0 - 0 0
GEORGETOWN MUNI AIRPORT 37 63 44 65 46 / 0 0 - 20 10
HONDO MUNI AIRPORT 38 63 45 66 43 / 0 0 10 10 0
SAN MARCOS MUNI AIRPORT 38 63 45 65 46 / 0 0 20 20 10
LA GRANGE - FAYETTE REGIONAL 40 64 48 66 50 / 0 0 20 40 10
SAN ANTONIO INTL AIRPORT 40 63 47 65 47 / 0 0 20 20 -
STINSON MUNI AIRPORT 41 63 48 65 46 / 0 0 20 20 -
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...ALLEN
SYNOPTIC/GRIDS...17
PUBLIC SERVICE/DATA COLLECTION...30
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
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
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 JACKSON KY
335 AM EST WED JAN 13 2016
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 335 AM EST WED JAN 13 2016
07Z SFC ANALYSIS SHOWS COLD HIGH PRESSURE BUILDING INTO KENTUCKY.
THIS IS HELPING TO SETTLE THE WINDS AND HAS CLEARED THE SKY. AS A
RESULT...TEMPERATURES ARE DROPPING TOWARD 10 DEGREES IN THE
EASTERN VALLEYS AND NORTHWEST PARTS OF THE AREA WHILE MID AND
UPPER TEENS ARE FOUND ON THE RIDGES AND THROUGH THE CUMBERLAND
VALLEY. DEWPOINTS...MEANWHILE ARE IN THE SINGLE DIGITS MOST
PLACES. THE SNOW SQUALLS OF TUESDAY AFTERNOON SPARED MOST
LOCATIONS GENERALLY SOUTH OF THE MOUNTAIN PARKWAY BUT DID MANAGE
TO LAY DOWN A LAYER OF SNOW OF VARYING THICKNESS NORTH OF THE
HIGHWAY...AND PARTICULARLY FOR POINTS ALONG AND NORTH OF
INTERSTATE 64. THESE PLACES WILL RADIATE EXTRA WELL FOR THE REST
OF THE NIGHT WITH SOME SINGLE DIGITS CERTAINLY POSSIBLE BY DAWN.
WILL LIKELY DO SOME FINAL ADJUSTMENTS TEMPS IN THESE PLACES
BEFORE GRID ISSUANCE.
THE MODELS ARE IN EXCELLENT AGREEMENT ALOFT THROUGH THE SHORT
TERM PORTION OF THE FORECAST. THEY ALL DEPICT A CLUSTER OF WEAK
MID LEVEL WAVES PASSING THROUGH THE OHIO VALLEY TODAY AND TONIGHT
IN NORTHWEST FLOW...EVEN AS THE HEIGHTS CONTINUE TO REBOUND.
EASTERN KENTUCKY WILL GET INTO SOME SLIGHT RIDGING ON THURSDAY
AHEAD OF A STILL UNCONSOLIDATED TROUGH MOVING INTO THE CENTRAL
PLAINS AND ANOTHER WEAK ONE LIFTING NORTHEAST FROM NORTHERN
MEXICO IN THE SOUTHERN STREAM. LOOK FOR THESE TO START TO INTERACT
AND BRING A CHANCE OF RAIN TO THE AREA EARLY IN THE EXTENDED. IN
THE MEANTIME...THOUGH...A QUIET MID LEVELS AND DRY AIR IN PLACE
WILL KEEP THE WEATHER RATHER BENIGN THROUGH THURSDAY. HAVE FAVORED
THE HIGHER RESOLUTION GUIDANCE FROM THE HRRR AND NAM12 FOR
FORECAST DETAILS.
SENSIBLE WEATHER WILL FEATURE A CHILLY START WITH TEMPERATURES IN
THE TEENS AND SINGLE DIGITS THIS MORNING ALONG WITH WIND CHILLS
NEAR ZERO AT TIMES. HOWEVER...PLENTY OF SUNSHINE IN THE MORNING
WILL HELP THE MERCURY REBOUND TO ABOVE FREEZING AND INTO THE MID
30S DURING THE AFTERNOON...FOR MOST PLACES WITHOUT A SNOW PACK.
LOCATIONS ALONG AND NORTH OF INTERSTATE 64 WILL STRUGGLE TO SEE
FREEZING TEMPS...THOUGH. A PASSING AREA OF LOW PRESSURE TO THE
NORTH WILL BRING SOME MID LEVEL CLOUDS TO THE NORTHERN PARTS OF
THE CWA THIS AFTERNOON AND EVENING BUT NO PCPN OR FLURRIES ARE
EXPECTED FROM THESE. MILDER TEMPERATURES ARE ON TAP FOR TONIGHT AS
WARMER AIR STARTS TO MOVE IN AND THE HIGH RETREATS TO THE EAST.
THE WARMUP WILL BE MOST PRONOUNCED ON THURSDAY WHEN SOUTHWEST
WINDS KICK IN SUPPORTING TEMPERATURES TOPPING OUT IN THE UPPER 40S
AND LOWER 50S.
AGAIN USED THE SHORTBLEND AS A STARTING POINT FOR TEMPS AND
DEWPOINTS THROUGH THE EVENING FOLLOWED BY THE SUPERBLEND. DID MAKE
SOME ADJUSTMENTS TONIGHT TO HIGHLIGHT A DECENT RIDGE TO VALLEY
TEMPERATURE SPLIT. AS FOR POPS...THEY ARE BASICALLY LOW SINGLE
DIGITS OR NEAR ZERO THROUGH THE SHORT TERM...IN LINE WITH MOS
GUIDANCE.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 335 AM EST WED JAN 13 2016
BIG STORY TO BEGIN THIS PERIOD WILL BE THE CONTINUED ABOVE AVERAGE
TEMPERATURES. WE BEGIN THE PERIOD WITH SURFACE HIGH PARKED TO OUR
SOUTHEAST AND IN THE WARM SECTOR. THIS WILL BE AHEAD OF DEEPENING
UPPER LEVEL TROUGH ACROSS THE NORTHERN CENTRAL PLAINS. THAT SAID
THIS WILL BE THE NEXT WEATHER MAKER TO END THE WORK WEEK AND START
OF THE WEEKEND. THIS UPPER LEVEL TROUGH WILL CONTINUE TO DIG AS
IT MOVES EAST AND PIVOTS INTO THE MID ATLANTIC...ALL WHILE
BECOMING NEGATIVELY TILTED. THERE ARE SOME ISSUES THAT WILL HAVE
TO BE LOOKED AT WITH THIS SYSTEM MORE AS WE GET CLOSER. THE FIRST
IS AS THE TROUGH NEGATIVELY TILTS ALONG THE MID ATLANTIC AND A
300MB JET STREAK PUNCHES IN FROM THE GULF OF MEXICO...A SURFACE
LOW WILL CONTINUE TO DEEPEN ACROSS THE SE. THIS COULD PLAY A ROLE
IN CUTTING OFF SOME OF THE MOISTURE WITH THIS SYSTEM AND WILL
HAVE TO BE RESOLVED FURTHER...THE NAM AND GFS HAVE THE MOST
CONSISTENCY WITH BETTER QPF NW ACROSS NORTH CENTRAL KY. EVEN SO
KEPT CLOSE TO PREVIOUS FORECAST IN TERMS OF POPS GIVEN THE FACT
THAT WE WILL PROBABLY SEE SOMETHING MEASURABLE. NOW THE BEST LIFT
WILL BE IN THE EVENING HOURS ON FRIDAY AND LIFT TRAILS OFF FROM
THERE.
THE NEXT ISSUE WILL BE TRANSITION FROM RAIN TO SNOW
OVERNIGHT...RIGHT NOW TRANSITION IN THE FAR WEST NEAR DAWN AND
MOVE THAT TRANSITION THROUGH THE MORNING. IT DOES LOOK LIKE MUCH
OF THIS SHOULD REMAIN SNOW SHOWER ON SATURDAY. OVERALL NOT LOOKING
AT MUCH IN TERMS OF ACCUMULATION GIVEN THE WARM TEMPS PRIOR. AFTER
THIS WE ARE POISED TO MOVE BACK TO THE MUCH COLDER AIR AFTER THE
QUICK WARM UP. RIGHT NOW MODELS ARE HAVING TROUBLE RESOLVING WHAT
WILL HAPPEN HERE SUNDAY...BUT SEEMS LIKE THEY ARE CATCHING ON TO
THE FACT THAT ANOTHER ARCTIC FRONT WILL PASS ACROSS THE REGION.
THAT SAID DID LEAN TOWARD THE BLEND FOR THIS WHICH BRINGS SOME
SLIGHT TO CHANCE POPS INTO THE PICTURE...ANY SNOW ACCUM IS
EXPECTED TO REMAIN LIGHT. THAT SAID SOME MUCH COLD AIR ARRIVES
INTO THE REGION BEHIND THIS FRONT...WITH 850MB TEMPS IN THE MINUS
20 RANGE NOT OUT OF THE QUESTION. MONDAY COULD BE THE FIRST TIME
THIS WINTER SEASON THAT WE ONLY MAKE IT INTO THE MID TO UPPER 20S
FOR MOST. OVERNIGHT LOWS FOR BOTH SUNDAY AND MONDAY NIGHT WILL
LIKELY BE IN THE TEENS WITH SINGLE DIGITS CERTAINLY NOT OUT OF THE
REALM OF POSSIBILITY PARTICULARLY MONDAY NIGHT. ALL THIS SAID
WITH SURFACE HIGH BUILDING THE FIRST PART OF YOUR WORK WEEK LOOKS
WELL BELOW AVERAGE TEMP WISE...BUT WILL REMAIN DRY.
OVERALL STUCK WITH MODEL BLEND THROUGH THE PERIOD...DID GO HIGHER
THAN BLEND INLINE WITH PREVIOUS FORECAST FOR THE WEEKEND SYSTEM.
ALSO TEMP WISE ON FRIDAY DID BUMP THAT UP JUST GIVEN THE STRONG
LLJ THAT KICKS INTO GEAR IN THE AFTERNOON. ALSO KEPT THE FORECAST
DRY FOR MONDAY WITH MOST OF THE MODELS NOW DEPICTING THAT THOUGHT.
DID ADD SOME RIDGE/VALLEY SPLITS AT THE END OF THE PERIOD
PARTICULARLY AS HIGH CRESTS ACROSS THE REGION.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 120 AM EST WED JAN 13 2016
CONDITIONS WILL BE VFR FOR THE REMAINDER OF THE NIGHT AND INTO
THE DAY WEDNESDAY AS AN AREA OF HIGH PRESSURE MOVES IN OVERHEAD.
THIS WILL CONTINUE TO SETTLE THE WINDS...DROPPING THEM TO LESS
THAN 10 KNOTS FOR THE REMAINDER OF THE PERIOD...GENERALLY FROM THE
WEST.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...GREIF
LONG TERM...DJ
AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS GRAY ME
1110 PM EST TUE JAN 12 2016
.SYNOPSIS...
LOW PRESSURE MOVING ACROSS THE GULF OF MAINE TONIGHT WILL
INTENSIFY AS IT MOVES NORTHEAST INTO THE MARITIMES ON WEDNESDAY.
THIS WILL PRODUCE A ROUND OF SNOW TONIGHT...HEAVY AT TIMES ACROSS
CENTRAL AND MIDCOAST MAINE. AS THE STORM EXITS IT WILL ALSO
PRODUCE WINDY BUT FAIR CONDITIONS ON WEDNESDAY. HIGH PRESSURE
BUILDS IN THURSDAY AND FRIDAY. ANOTHER ROUND OF SNOW...POSSIBLY
RAIN NEAR THE COAST IS EXPECTED ON SATURDAY...WITH COLDER AIR
MOVING IN SUNDAY AND MONDAY.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
1110 PM UPDATE...HAVE ISSUED A SPECIAL WEATHER STATEMENT FOR THE
HEAVY SNOW BAND THAT IS MOVING ACROSS SOUTHERN AND CENTRAL MAINE.
HOURLY RATES OF UP TO 3 INCHES ARE LIKELY...ALONG WITH ISOLATED
THUNDER. HAVE EXPANDED THE WINTER STORM WARNING TO ANDROSCOGGIN
COUNTY FOR THE NEXT FEW HOURS AS MORE THAN 6 INCHES IS NOW
EXPECTED BASED ON UPSTREAM REPORTS OVER INTERIOR CUMBERLAND
COUNTY.
1020 PM UPDATE...HAVE UPDATED THE FORECAST BASED ON LATEST TRENDS
IN RADAR AND OTHER OBSERVATIONAL DATA. THE BACK EDGE OF THE HEAVY
SNOW SHIELD IS MOVING QUICKLY TO THE NORTHEAST ACROSS SOUTHERNMOST
ME AND THIS TREND WILL CONTINUE. RAIN HUGGING THE MAINE COAST WILL
GRADUALLY GO BACK OVER TO SNOW OVER THE NEXT FEW HOURS FROM SOUTH
TO NORTH. HAVE CANCELLED THE ADVISORIES FOR SOUTHERN NH AS THE
SNOW HAS ENDED THERE. A FEW SQUALLS MAY AFFECT WESTERN ZONES
OVERNIGHT HOWEVER.
PREVIOUSLY...
A POTENT S/WV TROF IS CROSSING THE ERN GREAT LAKES AT THIS
HOUR...AND WILL BRING SOME SIGNIFICANT IMPACTS TO THE AREA THIS
EVENING AND TONIGHT.
THE STRENGTH OF THIS S/WV IS EVIDENT IN THE WILD WX THIS
AFTERNOON ACROSS UPSTATE NY. THUNDER HAS BEEN REPORTED AROUND BUF
IN HEAVY SNWFL...WITH WIND GUSTS IN EXCESS OF 60 MPH. THESE
SQUALLS MARK THE LEADING EDGE OF THE S/WV TROF. AHEAD OF
IT...INCREASING SLY FLOW AND WAA IS ALLOWING LIGHT SNWFL TO BREAK
OUT. THIS WILL INCREASE IN COVERAGE AND INTENSITY AS THE S/WV
APPROACHES. THIS WILL LEAD TO MINOR ACCUMULATIONS THRU THE EVENING
COMMUTE...BUT COULD LEAD TO SLIPPERY ROADS WITH TEMPS NEAR
FREEZING.
ATTENTION THEN TURNS TO THAT LEADING EDGE OF THE S/WV AND
ATTENDANT SQUALLS. HI-RES MODEL GUIDANCE SUGGESTS IT BECOMES
DIFFICULT TO DISTINGUISH BETWEEN THE LINE OF SN SHOWERS AND THE
DEVELOPING STRONG INFLOW JET FORECAST TO FORM NEAR SERN NH. 12Z
MODEL GUIDANCE SHIFTED THIS AREA OF FORMATION SLIGHTLY SW FROM 00Z
MODEL SUITE. THIS BRINGS AREAS LIKE MHT AND ASH A LITTLE CLOSER TO
THE BRIEF HEAVY SNWFL THREAT. HRRR GUIDANCE...ALONG WITH
ARW...NMM...AND REGIONAL CMC ALL SHOW THE POTENTIAL FOR QPF...AND
THUS SNWFL...TO BRIEFLY BE HEAVY AS THIS INFLOW JET SWEEPS NEWD
THRU THE FORECAST AREA. SNWFL RATES MAY EXCEED 1 TO 3 INCHES PER
HOUR IN THE HEAVIEST SNWFL...THOUGH MAY ONLY LAST FOR AN HOUR OR
SO. MIXING ANY OF THAT WIND ALOFT DOWN IN HEAVY SHOWERS COULD ALSO
BRING 30 TO 35 MPH GUSTS...WHICH WOULD LEAD TO NEAR ZERO
VISIBILITY AT TIMES. I HAVE AN SPS IN EFFECT TO HIGHLIGHT THIS
SHORT DURATION...HEAVY SNWFL ASPECT OF THE SYSTEM. IN
ADDITION...LAPSE RATES ALOFT EXCEED 7 C/KM...SUFFICIENT FOR STRONG
WARM SEASON CONVECTION LET ALONE WINTER. WILL KEEP THUNDER IN THE
FORECAST FOR AREAS NEAR THE COAST WHERE THIS UNSTABLE AIR MASS IS
ABLE TO MOVE IN OFF THE WATER. ANY CONVECTION WILL FURTHER ENHANCE
THOSE SNWFL RATES.
S/WV TROF CONTINUES NEGATIVE TILT THRU THE AREA...AND BAND OF
SNWFL SHOULD BEGIN TO SLOW AND PIVOT AS IT APPROACHES CENTRAL ME.
HEAVIEST AMOUNTS WILL BE IN OUR ERN ZONES...GENERALLY FROM AUG
NEWD. AGAIN WILL HAVE TO MONITOR BOUNDARY LAYER TEMPS NEAR THE
COAST...AS MODELS CONTINUE TO SUGGEST WARMING MAKING IT WELL
INLAND. TEMPS ALOFT WOULD ARGUE THAT THIS STRUGGLES TO MAKE
PROGRESS MUCH PAST THE NECKS AND ISLANDS. CAPE ELIZABETH AND MAYBE
EVEN PWM MAY BE RA...WHILE THE TURNPIKE IS HEAVY SNWFL. HOWEVER
TOO MUCH UNCERTAINTY EXISTS TO CHANGE HEADLINES FROM WHERE WE HAVE
THEM CURRENTLY. SNWFL AMOUNTS LOOK VERY SIMILAR TO PREVIOUS
SHIFT...MAYBE SLIGHTLY HIGHER OVER SWRN ME. HOWEVER THESE STILL
FALL WITHIN ADVISORY RANGE. STILL A LOW CHANCE THAT SOME OF THE
ADVISORY MAY NEED TO BE CONVERTED TO WARNINGS AS THE BANDING SETS
UP.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/...
LOW PRES DEEPENS INTO THE 970S OVER THE CANADIAN MARITIMES
WED...SETTING UP A STRONG PRES GRADIENT ACROSS THE AREA. FLOW IN
CAA WILL BECOME GUSTY EARLY WED...INCREASING IN THE AFTERNOON AS
THE CORE OF WLY JET AROUND 5000 FEET MOVES OVERHEAD. BUFKIT
SOUNDINGS SHOW SOME POTENTIAL TO MIX DOWN SOME OF THIS JET...WITH
A FEW MODELS SHOWING GUSTS IN THE 40 TO 45 KT RANGE. GIVEN THAT A
WIND HEADLINE WOULD COMPLICATE AN ALREADY COMPLICATED FORECAST
EVEN FURTHER...WILL HOLD OFF FOR NOW AND ALLOW THE MIDNIGHT SHIFT
TO REASSESS.
UPSLOPE SN SHOWERS WILL LINGER OVER THE NRN ZONES IN WLY FLOW WED.
AN ADDITIONAL COUPLE OF INCHES IS POSSIBLE IN THE FAVORED AREAS.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
HIGH IMPACT WX: LOW CONFIDENCE FOR SIGNIFICANT SNOW CENTERED
AROUND SATURDAY.
THE 500 MB PATTERN CONTINUES TO BUILD WEAK TO MODERATE RIDGING
ACROSS THE WRN CONUS AND ERN PACIFIC...WITH A MEAN...BUT
FLUCTUATING TROUGH OVER THE ERN CONUS. ALL IN ALL THOUGH...SO
CALLED PINEAPPLE EXPRESS ACROSS THE PACIFIC WILL PROVIDE ENOUGH
WAVES TO CONTINUALLY KNOCK DOWN THE RIDGE IN THE WEST...AND LACK
OF COLD AIR OVER NOAM WILL LIMIT THERMAL ADVECTION ENOUGH IN THE
ARCTIC TO MINIMIZE WAVE PRODUCTION TO MAINTAIN SOLID TROUGH OVER
ERN CONUS. THIS...WILL SEE SOME CHANGEABLE CONDS THRU THE EXTENDED
WITH TEMPS FLUCTUATING SEVERAL DEGREES EITHER SIDE OF NORMAL.
SENSIBLE WX WILL SEE SFC RIDGE SLOWLY PASSING TO OUR S THU AND
FRI...WITH SFC LOW MOVING NE INTO THE GREAT LAKES FRI NIGHT. 500MB
WEAVE ROTATING AROUND THE BASE OF THE TROUGH WILL DEVELOP COASTAL
BY SAT MORNING WHICH TRACKS OFF NEW ENGLAND COAST SAT. THIS WILL
BE OUT NEXT PRECIP MAKER. MED RANGE MODELS IN BETTER AGREEMENT ON
TIMING...WITH PRECIP STARTING SOMETIME FRI NIGHT AND ENDING SAT
NIGHT. TRACK AND INTENSITY FORECASTS VARY QUITE A
BIT...PARTICULARLY WHERE P-TYPE AND INTENSITY ARE CONCERNED WITH
THE GFS MOVING THE LOW FURTHEREST OFFSHORE...WHILE THE GGEM IS THE
CLOSEST...WITH THE EURO IN THE MIDDLE. SO WHILE SOME PRECIP CAN BE
EXPECTED...AND IT WILL LIKELY BE SNOW INLAND...EVERYTHING ELSE
STILL REMAINS LOW CONFIDENCE. UPPER LVL LOW CROSSES THE REGION
SUNDAY WITH SHSN POSSIBLE...AND COLDER HIGH PRESSURE EXPECTED
EARLY NEXT WEEK.
&&
.AVIATION /04Z WEDNESDAY THROUGH SUNDAY/...
SHORT TERM...CONDITIONS WILL IMPROVE RAPIDLY FROM SW TO NE LATE
THIS EVENING AND OVERNIGHT AS THE SNOW SHIELD MOVES NORTHEASTWARD.
GUSTY WEST WINDS AND VFR CONDITIONS WILL FOLLOW LATER TONIGHT AND
WEDNESDAY.
LONG TERM...VFR WED NIGHT THROUGH FRI. FLIGHT RESTRICTIONS
EXPECTED LATE FRI NIGHT INTO SAT EVE IN SN...OR POSSIBLE RA NEAR
THE COAST. SOME IMPROVEMENT IS POSSIBLE ON SUN.
&&
.MARINE...
SHORT TERM...GALE WARNINGS REMAIN IN EFFECT FOR ALL WATERS THRU
WED. WINDS MAY GUST TO NEAR STORM FORCE FOR A TIME IN STRONG CAA
WED.
LONG TERM...WINDS GRADUALLY DIMINISH FROM GALES WED EVE...TO SCA
FOR THU....AND BELOW SCA THU NIGHT THRU FRI NIGHT. SCA OR GALES
POSSIBLE AGAIN SAT AND SAT NIGHT.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...WINTER STORM WARNING UNTIL 10 AM EST WEDNESDAY FOR MEZ008-009-
013-014-021-022-028.
WINTER WEATHER ADVISORY UNTIL 4 AM EST WEDNESDAY FOR MEZ007-
012-019.
WINTER WEATHER ADVISORY UNTIL 10 AM EST WEDNESDAY FOR
MEZ025>027.
WINTER WEATHER ADVISORY UNTIL 1 AM EST WEDNESDAY FOR MEZ024.
WINTER STORM WARNING UNTIL 3 AM EST WEDNESDAY FOR MEZ020.
NH...WINTER WEATHER ADVISORY UNTIL 4 AM EST WEDNESDAY FOR NHZ001-
002.
MARINE...GALE WARNING UNTIL 11 PM EST WEDNESDAY FOR ANZ150>154.
&&
$$
NEAR TERM...EKSTER
SHORT TERM...LEGRO
LONG TERM...CEMPA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1221 AM EST WED JAN 13 2016
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 429 PM EST TUE JAN 12 2016
WATER VAPOR IMAGERY AND RAP ANALYSIS CONTINUE A SHOW A TROF
EXTENDING FROM HUDSON BAY INTO THE GREAT LAKES REGION. IN THE WAKE
OF THE VIGOROUS SHORTWAVE THAT IS MOVING THRU THE LWR GREAT LAKES
ATTM...DRIER AIR...SUBSIDENCE AND FALLING INVERSION HEIGHTS (NOW
AROUND 5KFT W AND 7KFT E PER LATEST RAP) HAVE RESULTED IN SOME
DIMINISHING OF LES TODAY...THOUGH SOME MDT SNOW SHOWERS CONTINUE.
INVERSION HEIGHTS REMAIN RELATIVELY STEADY STATE TONIGHT...BUT THERE
ARE SOME AREAS OF CONCERN AS WINDS SLOW BACK. FIRST...OVER THE NE
FCST AREA...STRENGTHENING LAND BREEZES IN CONCERT WITH LARGER SCALE
BACKING WINDS OVER UPPER MI WILL LEAD TO INCREASING LOW-LEVEL
CONVERGENCE FROM ALGER COUNTY INTO NRN LUCE COUNTY. ALONG WITH THE
LONG FETCH...EXPECT 3-5 INCHES OF SNOW IN GENERAL FROM AROUND GRAND
MARAIS E ACROSS NRN LUCE COUNTY. SNOW WILL END IN WRN ALGER COUNTY
TONIGHT AS BANDS SHIFT E UNDER BACKING WINDS. MOST OF THE LES SHOULD
BE OFFSHORE BY SUNRISE...THOUGH SOME LES WILL BRUSH THE SHORELINE
FROM GRAND MARAIS EASTWARD IN THE MORNING. ALGER COUNTY LES ADVY HAS
BEEN EXTENDED TO 12Z WED WITH LUCE ADDED TO THAT.
TO THE W...A TYPICAL CONVERGENCE PATTERN WILL DEVELOP AS BACKING
WINDS AIDED BY LAND BREEZE RESULTS IN WSW WINDS DEVELOPING OVER THE
SRN PART OF WRN LAKE SUPERIOR. MEANWHILE...WINDS REMAIN MORE WNW
BTWN THE KEWEENAW AND ISLE ROYALE. END RESULT IS ENHANCED
CONVERGENCE SETTING UP ACROSS THE MID PORTION OF WRN LAKE
SUPERIOR...AIMED INTO THE FAR NRN PART OF ONTONAGON COUNTY AND INTO
CNTRL HOUGHTON COUNTY...ROUGHLY BTWN TWIN LAKES AND PAINESDALE. HIGH
RES MODEL GUIDANCE IS IN GOOD AGREEMENT ON THIS SCENARIO WITH ONLY
SUBTLE DIFFERENCES IN PLACEMENT OF HEAVIEST QPF. CONVERGENCE BAND
MAY SHIFT N SLIGHTLY DURING THE DAY WED AND AFFECT THE HOUGHTON
AREA. LES WILL BE LIGHT THIS EVENING AS FLOW ADJUSTS OVER WRN LAKE
SUPERIOR. LES SHOULD THEN INCREASE OVERNIGHT THRU WED IN THE
AFORMENTIONED AREA AS THE CONVERGENCE ZONE SETS UP. THERE IS SOME
INDICATION FOR A SLIGHT LIFTING OF THE INVERSION LATE TONIGHT/WED
AND LIFTING OF THE DGZ TO ENCOMPASS MORE OF THE CONVECTIVE
LAYER...ESPECIALLY WED. SO...GREATER SNOW ACCUMULATIONS WILL OCCUR
DURING THE DAY WED. EXPECT GENERALLY 2-4 INCHES OF SNOW
TONIGHT...THEN 3-7 INCHES OF SNOW WED. ADVY WILL ONLY BE CARRIED FOR
NRN HOUGHTON COUNTY WHERE BEST SNOWFALL IS EXPECTED. IF IT LATER
LOOKS LIKE MORE OF NRN ONTONAGON COUNTY MAY BE IMPACTED...ADVY WILL
NEED TO BE EXPANDED.
OTHER POTENTIAL CONCERN IS WIND CHILL HEADLINES IN THE COUNTIES
ALONG THE MI/WI BORDER. WITH MIN TEMPS CURRENTLY EXPECTED AROUND
-10F AND SUSTAINED WINDS LESS THAN 10 MPH...APPARENT TEMPS END UP
JUST SHY OF THE -25F THRESHOLD FOR WIND CHILL ADVY. WILL BE
SOMETHING TO MONITOR DURING THE EVENING IN THE EVENT TEMPS FALL MORE
THAN EXPECTED AND/OR WINDS ARE A BIT STRONGER.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 429 PM EST TUE JAN 12 2016
WARMER AIR WILL BE MOVING IN STARTING WEDNESDAY NIGHT. NW FLOW AND
AN ELONGATED SHORTWAVE WILL CONTINUE ALOFT WITH A 300MB JET AROUND
120KTS. THE FOCUS FOR ANY LINGERING MODERATE SNOW SHOWERS WILL BE
OVER THE NW FAVORED WIND SNOW BELTS OF THE KEWEENAW PENINSULA.
ELSEWHERE...MORE OF AN OFFSHORE OR PARALLEL SHORE FLOW IS
ANTICIPATED OVER THE E. ANOTHER 1-2IN OF SNOW WILL BE POSSIBLE FROM
THE PORCUPINE MTNS THROUGH THE TIP OF THE KEWEENAW...AND THEN RIGHT
ALONG THE SHORELINE FROM GRAND MARAIS TO WHITEFISH POINT.
THE 500MB LOW SPINNING OVER W HUDSON BAY WILL BEGIN TO SINK
OVER N MANITOBA. AS A RESULT...LOOK FOR A MORE W FLOW TO TAKE HOLD
OVER THE UPPER GREAT LAKES ON THURSDAY AS A TROUGH EXTENDS S FROM
THE 500MB LOW ALL THE WAY THROUGH THE CENTRAL PLAINS AND DOWN TROUGH
THE GULF OF MEXICO. SYNOPTIC SNOW/SNOW SHOWERS SHOULD WILL RETURN
THURSDAY...AHEAD OF THE COMBINING N LOWS SINKING ACROSS THE N AND
CENTRAL PLAINS. THERE HAS BEEN SOME DIFFERENCES ON THE TRACK OF THIS
LOW OVER THE PAST 24 HOURS. YESTERDAY THEY SHOWED MORE OF A S
TREND...LIKE THE 12Z SREF /OVER E KS/OK AT 06Z FRIDAY/. SINCE THEN
THEY ARE A BIT MORE N INTO IA. EITHER WAY...A PERSISTANT NE-N SFC
FLOW LOOKS TO SET IN ACROSS LAKE SUPERIOR AND UPPER MI FRIDAY
AFTERNOON THROUGH SATURDAY EVENING AS THE SFC LOW EXITS ACROSS THE
LOWER GREAT LAKES. THIS FEATURE LOOKS TO JOIN FORCES WITH ANOTHER
LOW DEEPENING AS IT TRACKS UP THE E SEABOARD SATURDAY. THE RESULT
WILL BE A STEADY TROUGH OVER OUR AREA WITH N-NW FLOW THROUGH TUESDAY
AS A SFC HIGH OVER THE PLAINS SUNDAY NIGHT SLOWLY ATTEMPS TO BUILD
IN OVER THE FIRST HALF OF THE WORK WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1220 AM EST WED JAN 13 2016
WINDS CONTINUING TO BACK THRU THE PERIOD SHOULD ALLOW KSAW TO
REMAIN VFR THROUGH MUCH OF PERIOD UNDER A DOWNSLOPE WSW WIND
COMPONENT. AT KIWD...BANDS SHOULD SHIFT N OF THE TERMINAL
OVERNIGHT ALLOWING FOR VFR CONDITIONS TO PREVAIL THIS
MORNING...ALTHOUGH MVFR CLOUDS WILL MOVE BACK IN WED AFTERNOON AS
ANOTHER DISTURBANCE/TROUGH MOVES THROUGH THE REGION. AT
KCMX...-SHSN WILL CONTINUE WITH A WIND TRAJECTORY OFF THE LAKE.
EXPECT IFR CONDITIONS TO MOSTLY PREVAIL...BUT AS IS TYPICAL FOR LAKE
EFFECT...CONDITIONS WILL BE VARIABLE WITH SOME MVFR AND LIFR AT
TIMES.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 404 PM EST TUE JAN 12 2016
WINDS WILL RELAX TONIGHT...AND REMAIN UNDER 25KTS THROUGH THROUGH
THURSDAY NIGHT /DOWN TO LESS THAN 15KTS FOR MUCH OF LAKE SUPERIOR
LATE WEDNESDAY NIGHT THROUGH THURSDAY/. HOWEVER...THERE COULD STILL
BE SOME HEAVY FREEZING SPRAY OVER THE E HALF OF LAKE SUPERIOR EARLY
THIS EVENING. LOW PRESSURE ALONG THE S ONTARIO AND QUEBEC BORDER
WILL EXIT NE OF MAINE OVERNIGHT. A TROUGH WILL LINGER OVER LAKE
SUPERIOR AS A RIDGE ACROSS MINNESOTA THIS EVENING SLIDES ACROSS WI
OVERNIGHT...AND THEN TO THE SE STATES WEDNESDAY. EXPECT THE TROUGH
OVER LAKE SUPERIOR TO DEEPEN WEDNESDAY INTO THURSDAY.
TWO AREAS OF LOW PRESSURE OVER N MANITOBA AND THE DAKOTAS THURSDAY
MORNING ARE EXPECTED TO COMBINE AND SHIFT ACROSS THE CENTRAL PLAINS
THURSDAY NIGHT-FRIDAY. NE GUSTS OF 25-30KTS WILL RETURN FRIDAY
AFTERNOON...AND LINGER THROUGH MUCH OF THE PERIOD WHILE TURNING MORE
OUT OF THE N-NNW /ESPECIALLY OVER THE E HALF OF LAKE SUPERIOR/.
THE LOW WILL LIFT NE ACROSS LOWER MI FRIDAY NIGHT AND EXIT
ACROSS N NY SATURDAY NIGHT AS A STRONGER LOW RIDES UP THE E
SEABOARD. LOOK FOR THE LINGERING RIDGE TO WEAKEN ACROSS LAKE
SUPERIOR AS A HIGH PRESSURE SYSTEM MOVES FROM CANADA TO THE N AND
CENTRAL PLAINS SUNDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY UNTIL 7 AM EST THIS MORNING FOR MIZ006-
007.
LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST THIS EVENING FOR MIZ003.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...KF
AVIATION...VOSS
MARINE...KF
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
444 AM EST WED JAN 13 2016
.SYNOPSIS...
HEAVY LAKE EFFECT SNOW WILL CONTINUE TODAY IN PARTS OF CENTRAL NEW
YORK DOWNWIND OF LAKE ONTARIO...ESPECIALLY THE SYRACUSE METRO
AREA. THE REST OF THE REGION WILL BE COLD AND BRISK WITH SCATTERED
SNOW SHOWERS OR FLURRIES. LIGHT SNOW IS POSSIBLE WITH ANOTHER CLIPPER
SYSTEM LATE TONIGHT INTO THURSDAY. A STRONGER SYSTEM IS EXPECTED FRIDAY
NIGHT THROUGH SATURDAY NIGHT WITH A MIX OF RAIN AND SNOW POSSIBLE.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
410 AM UPDATE...
HEAVY LAKE EFFECT SNOW IS ONGOING IN PARTS OF CENTRAL NEW YORK. AS
IS TYPICAL...THE BAND /OR AT TIMES BANDS/ IS FLUCTUATING IN
PLACEMENT BY THE HOUR. THIS IS OCCURRING WITH EACH PASSING RIPPLE
EMBEDDED WITHIN THE FLOW ON THE BACK SIDE OF THE UPPER TROUGH THAT
IS GRADUALLY LIFTING NORTHEAST. 1 TO 2 INCH PER HOUR SNOWFALL
RATES WILL CONTINUE WITHIN THE HEAVIEST BANDS EARLY THIS
MORNING...NOW SLAMMING THE SYRACUSE METRO AREA EAST TO ABOUT
VERONA...TO SOUTH OF UTICA. LOCAL CONDITIONS WILL VARY WIDELY WITH
ABRUPT NEAR WHITE-OUT CONDITIONS POSSIBLE AT TIMES. WEST WIND WILL
ALSO STILL GUST TO 30 MPH THROUGH THE MORNING WHICH WILL TEND TO
DRIFT THE DRY AND FLUFFY SNOW. THIS WILL MAKE IT A CHALLENGE TO
KEEP ROADS CLEAR...ESPECIALLY NORTH-SOUTH ORIENTED ROUTES.
AN INTERRUPTION IN INTENSITY MAY OCCUR AROUND MID MORNING...BEFORE
THE BAND REINVIGORATES EARLY AFTERNOON WHILE SHIFTING GRADUALLY
NORTH AND CATCHING A LONGER FETCH DOWN THE LENGTH OF LAKE ONTARIO.
THUS FAR...A TOO-FAR-SOUTHWARD BIAS HAS BEEN DEPICTED BY ARW NMM
HRRR AND RUC MODELS...WHICH HAS BEEN OBSERVED TO BE COMMON WITH
LAKE ONTARIO LAKE EFFECT EVENTS IN THE PAST. I HAVE CONTINUED TO
LEAN ON THE CANADIAN AND TO A LESSER DEGREE THE NAM FOR
EXPECTATIONS OF BAND PLACEMENT. THAT BEING SAID...THERE IS SOME
SORT OF SMALL MCV/VORTICITY FEATURE THAT WAS OBSERVED CROSSING
LAKE HURON TO THE ONTARIO PENINSULA...AND NOW GETTING INTO FAR
WESTERN LAKE ONTARIO. I SUSPECT THIS IS WHAT MAY CAUSE THE LAKE
EFFECT TO LOSE A LITTLE ORGANIZATION LATER THIS MORNING...WHICH
THE LATEST 06Z NAM ALSO SEEMS TO BE LATCHING ON.
EARLY THIS AFTERNOON LAKE EFFECT SHOULD BE AGAIN PRETTY STOUT
ALONG THE NY THRUWAY AT FIRST...BUT LIFTING NORTHWARD WITH TIME.
IT SHOULD BE NORTH OF SYRACUSE BY MID AFTERNOON...NORTH OF UTICA
BY MID-TO-LATE AFTERNOON...AND THEN EXIT NORTHERN ONEIDA COUNTY
EARLY EVENING.
FOR THE REST OF THE REGION...GENERALLY JUST A COLD BRISK DAY WITH
SCATTERED SNOW SHOWERS AND FLURRIES...MAINLY TWIN TIERS NORTHWARD.
TEMPERATURES WILL PRETTY MUCH HOLD IN THE UPPER TEENS-LOWER 20S.
LAKE ERIE BANDS WILL AT TIMES EXTEND ACROSS THE CENTRAL TWIN
TIERS TO PROVIDE LIGHT DUSTINGS OF SNOW...WHICH THE WIND WILL
EASILY PICK UP AND BLOW AROUND. THERE COULD BE AN INCH OR TWO
ACCUMULATION ESPECIALLY STEUBEN-YATES- SCHUYLER. T
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/...
LAKE ONTARIO BAND WILL SHIFT NORTH OF THE AREA THIS EVENING...BUT
ALREADY IN THIS BUSY PATTERN...THE WARM AIR ADVECTION SIDE OF
ANOTHER CLIPPER WILL MOVE IN LATE TONIGHT INTO THURSDAY MORNING.
THIS COULD PROVIDE FOR A QUICK DUSTING TO INCH OF VERY LIGHT SNOW
FOR A GOOD CHUNK OF THE AREA. THE SURFACE LOW OF THE CLIPPER WILL
PASS TO OUR NORTH...AND THE ASSOCIATED COLD FRONT WILL PRETTY MUCH
WASH OUT IN OUR VICINITY THURSDAY NIGHT WITH LITTLE IMPACT EXCEPT
PERHAPS SPOTTY FLURRIES.
ON FRIDAY...WHAT IS LEFT OF THE CLIPPER FRONTAL ZONE WILL
EFFECTIVELY TURN BACK INTO A WARM FRONT AND LIFT OUT OF THE
AREA...AS SOUTHWEST FLOW DEVELOPS WELL AHEAD OF A STRONGER LOW
THAT WILL MOVE INTO THE WESTERN GREAT LAKES. THE RESULTING WARM
AIR ADVECTION WILL BOOST TEMPERATURES INTO UPPER 30S-LOWER 40S
FRIDAY...WHICH APPEARS TO BE MAINLY DRY.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
STRONG DUAL LOW SYSTEM MOVES INTO THE NORTHEAST WITH A WARM
SECTOR AHEAD OF THE LOW ALLOWING FOR THE POTENTIAL OF MIXED
PRECIPITATION FRIDAY NIGHT AND SATURDAY. THE SYSTEM LIFTS TO THE
E/NE LATE SATURDAY AND ANOTHER COLD ARCTIC AIR MASS DROPS IN FROM
THE NW AND CHANGES THE PRECIP OVER TO ALL SNOW. SOME ACCUMULATION
ON THE BACK SIDE OF THE SYSTEM IS POSSIBLE.
THE INFLUX OF ANOTHER ARCTIC AIR MASS AND A W/NWLY FLOW REGIME
WILL ALLOW FOR A PERIOD OF LAKE EFFECT SNOW SHOWERS SUNDAY NIGHT
THROUGH TUESDAY. SIGNIFICANT SNOWFALL ACCUMULATIONS ARE POSSIBLE.
COOL TEMPERATURES ARE EXPECTED THURSDAY WITH HIGHS IN THE MID TO
UPPER 20S AND LOWS IN THE TEENS AND SINGLE DIGITS. A BRIEF PERIOD
OF MILD TEMPERATURES IS ANTICIPATED FRIDAY AND SATURDAY WITH HIGHS
IN THE MID TO UPPER 30S AND LOWS IN THE 20S. A COLD AIR MASS WILL
DROP IN LATE IN THE WEEKEND AND REMAIN IN PLACE INTO EARLY NEXT
WEEK WITH HIGHS IN THE 20S AND LOWS IN THE TEENS.
&&
.AVIATION /10Z WEDNESDAY THROUGH SUNDAY/...
LAKE EFFECT SNOW BANDS AFFECT KSYR WITH ALTERNATE MINIMUM...AND
OCCASIONAL AIRPORT MINIMUM RESTRICTIONS TODAY THROUGH APPROXIMATELY
21Z. CONDITIONS THEN IMPROVE TO VFR. LAKE SNOW BANDS WILL
OSCILLATE IN AND OUT OF KRME TODAY WITH CONDITIONS VARYING FROM
MVFR TO AT LEAST ALTERNATE MIN RESTRICTIONS...IF NOT WORSE. TIMING
OF BANDS MOVING THROUGH THIS TERMINAL IS A LOW CONFIDENCE
FORECAST. USE TAF PERIODS BEYOND 6 HOURS FROM CURRENT TIME WITH
CAUTION.
ELSEWHERE...VFR-MVFR CIGS AND OCCASIONAL IFR SNOW SHOWERS AT KITH-
KELM-KBGM...ENDING AFTER 18Z-21Z. VFR FOR THE ENTIRE FORECAST PERIOD
AT KAVP...ALTHOUGH A VERY BRIEF MVFR SNOW SHOWER MAY SWEEP THROUGH
THE TERMINAL VICINITY THIS MORNING.
GUSTY WEST-NORTHWEST WINDS 15G35KT THIS MORNING DIMINISH TO 10-15
KTS THIS AFTERNOON...THEN SW 5-10 KTS TONIGHT.
.OUTLOOK...
THURS-FRI...MAINLY VFR.
SAT...MVFR/IFR IN RAIN/SNOW.
SUN...MVFR/IFR POSSIBLE SNOW SHOWERS.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...LAKE EFFECT SNOW WARNING UNTIL 7 PM EST THIS EVENING FOR
NYZ009-018-036-037.
LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST THIS EVENING FOR
NYZ046.
&&
$$
SYNOPSIS...MDP
NEAR TERM...MDP
SHORT TERM...MDP
LONG TERM...BJT
AVIATION...JAB
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
412 AM EST WED JAN 13 2016
.SYNOPSIS...
HEAVY LAKE EFFECT SNOW WILL CONTINUE TODAY IN PARTS OF CENTRAL NEW
YORK DOWNWIND OF LAKE ONTARIO...ESPECIALLY THE SYRACUSE METRO
AREA. THE REST OF THE REGION WILL BE COLD AND BRISK WITH SCATTERED
SNOW SHOWERS OR FLURRIES. LIGHT SNOW IS POSSIBLE WITH ANOTHER CLIPPER
SYSTEM LATE TONIGHT INTO THURSDAY. A STRONGER SYSTEM IS EXPECTED FRIDAY
NIGHT THROUGH SATURDAY NIGHT WITH A MIX OF RAIN AND SNOW POSSIBLE.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
410 AM UPDATE...
HEAVY LAKE EFFECT SNOW IS ONGOING IN PARTS OF CENTRAL NEW YORK. AS
IS TYPICAL...THE BAND /OR AT TIMES BANDS/ IS FLUCTUATING IN
PLACEMENT BY THE HOUR. THIS IS OCCURRING WITH EACH PASSING RIPPLE
EMBEDDED WITHIN THE FLOW ON THE BACK SIDE OF THE UPPER TROUGH THAT
IS GRADUALLY LIFTING NORTHEAST. 1 TO 2 INCH PER HOUR SNOWFALL
RATES WILL CONTINUE WITHIN THE HEAVIEST BANDS EARLY THIS
MORNING...NOW SLAMMING THE SYRACUSE METRO AREA EAST TO ABOUT
VERONA...TO SOUTH OF UTICA. LOCAL CONDITIONS WILL VARY WIDELY WITH
ABRUPT NEAR WHITE-OUT CONDITIONS POSSIBLE AT TIMES. WEST WIND WILL
ALSO STILL GUST TO 30 MPH THROUGH THE MORNING WHICH WILL TEND TO
DRIFT THE DRY AND FLUFFY SNOW. THIS WILL MAKE IT A CHALLENGE TO
KEEP ROADS CLEAR...ESPECIALLY NORTH-SOUTH ORIENTED ROUTES.
AN INTERRUPTION IN INTENSITY MAY OCCUR AROUND MID MORNING...BEFORE
THE BAND REINVIGORATES EARLY AFTERNOON WHILE SHIFTING GRADUALLY
NORTH AND CATCHING A LONGER FETCH DOWN THE LENGTH OF LAKE ONTARIO.
THUS FAR...A TOO-FAR-SOUTHWARD BIAS HAS BEEN DEPICTED BY ARW NMM
HRRR AND RUC MODELS...WHICH HAS BEEN OBSERVED TO BE COMMON WITH
LAKE ONTARIO LAKE EFFECT EVENTS IN THE PAST. I HAVE CONTINUED TO
LEAN ON THE CANADIAN AND TO A LESSER DEGREE THE NAM FOR
EXPECTATIONS OF BAND PLACEMENT. THAT BEING SAID...THERE IS SOME
SORT OF SMALL MCV/VORTICITY FEATURE THAT WAS OBSERVED CROSSING
LAKE HURON TO THE ONTARIO PENINSULA...AND NOW GETTING INTO FAR
WESTERN LAKE ONTARIO. I SUSPECT THIS IS WHAT MAY CAUSE THE LAKE
EFFECT TO LOSE A LITTLE ORGANIZATION LATER THIS MORNING...WHICH
THE LATEST 06Z NAM ALSO SEEMS TO BE LATCHING ON.
EARLY THIS AFTERNOON LAKE EFFECT SHOULD BE AGAIN PRETTY STOUT
ALONG THE NY THRUWAY AT FIRST...BUT LIFTING NORTHWARD WITH TIME.
IT SHOULD BE NORTH OF SYRACUSE BY MID AFTERNOON...NORTH OF UTICA
BY MID-TO-LATE AFTERNOON...AND THEN EXIT NORTHERN ONEIDA COUNTY
EARLY EVENING.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
THE LAKE EFFECT SNOW BANDS WILL SHIFT BACK TO THE NORTH LATE WED
AFTERNOON AND INTO THE EVENING AS THE WINDS BACK TO THE SW. WILL
ALSO SEE THE ARCTIC AIR GET SHUNTED TO THE NORTH AS WEAK RIDGING
OCCURS AHEAD OF A WEAK S/W EXPECTED LATER IN THE WORK WEEK.
LINGERING LIGHT SNOW OVER THE SOUTHERN TUG HILL PLATEAU WILL
CONTINUE INTO WED NIGHT...BUT ADDITIONAL AMOUNTS WILL BE LIGHT.
A WEAK S/W WILL MOVE ACROSS THE EASTERN GREAT LAKES ON THURSDAY
BUT MAINLY ACT TO INCREASE CLOUD COVER AND PRODUCE WIDESPREAD
LIGHT SNOW ACROSS THE FORECAST AREA.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
WAVE WASHES OUT LATE THURSDAY AS A MUCH BROADER AREA OF HIGH
PRESSURE BUILDS IN OVER THE NORTHEAST AHEAD OF A STRONG DUAL LOW
SYSTEM MOVES INTO THE NORTHEAST WITH A WARM SECTOR AHEAD OF THE
LOW ALLOWING FOR THE POTENTIAL OF MIXED PRECIPITATION FRIDAY NIGHT
AND SATURDAY. THE SYSTEM LIFTS TO THE E/NE LATE SATURDAY AND
ANOTHER COLD ARCTIC AIR MASS DROPS IN FROM THE NW AND CHANGES THE
PRECIP OVER TO ALL SNOW. SOME ACCUMULATION ON THE BACK SIDE OF THE
SYSTEM IS POSSIBLE.
THE INFLUX OF ANOTHER ARCTIC AIR MASS AND A W/NWLY FLOW REGIME
WILL ALLOW FOR A PERIOD OF LAKE EFFECT SNOW SHOWERS SUNDAY NIGHT
THROUGH TUESDAY. SIGNIFICANT SNOWFALL ACCUMULATIONS ARE POSSIBLE.
COOL TEMPERATURES ARE EXPECTED THURSDAY WITH HIGHS IN THE MID TO
UPPER 20S AND LOWS IN THE TEENS AND SINGLE DIGITS. A BRIEF PERIOD
OF MILD TEMPERATURES IS ANTICIPATED FRIDAY AND SATURDAY WITH HIGHS
IN THE MID TO UPPER 30S AND LOWS IN THE 20S. A COLD AIR MASS WILL
DROP IN LATE IN THE WEEKEND AND REMAIN IN PLACE INTO EARLY NEXT
WEEK WITH HIGHS IN THE 20S AND LOWS IN THE TEENS.
&&
.AVIATION /09Z WEDNESDAY THROUGH SUNDAY/...
LAKE EFFECT SNOW BANDS AFFECT KSYR WITH ALTERNATE MINIMUM...AND
OCCASIONAL AIRPORT MINIMUM RESTRICTIONS TODAY THROUGH APPROXIMATELY
21Z. CONDITIONS THEN IMPROVE TO VFR. LAKE SNOW BANDS WILL
OSCILLATE IN AND OUT OF KRME TODAY WITH CONDITIONS VARYING FROM
MVFR TO AT LEAST ALTERNATE MIN RESTRICTIONS...IF NOT WORSE. TIMING
OF BANDS MOVING THROUGH THIS TERMINAL IS A LOW CONFIDENCE
FORECAST. USE TAF PERIODS BEYOND 6 HOURS FROM CURRENT TIME WITH
CAUTION.
ELSEWHERE...VFR-MVFR CIGS AND OCCASIONAL IFR SNOW SHOWERS AT KITH-
KELM-KBGM...ENDING AFTER 18Z-21Z. VFR FOR THE ENTIRE FORECAST PERIOD
AT KAVP...ALTHOUGH A VERY BRIEF MVFR SNOW SHOWER MAY SWEEP THROUGH
THE TERMINAL VICINITY THIS MORNING.
GUSTY WEST-NORTHWEST WINDS 15G35KT THIS MORNING DIMINISH TO 10-15
KTS THIS AFTERNOON...THEN SW 5-10 KTS TONIGHT.
.OUTLOOK...
THURS-FRI...MAINLY VFR.
SAT...MVFR/IFR IN RAIN/SNOW.
SUN...MVFR/IFR POSSIBLE SNOW SHOWERS.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...LAKE EFFECT SNOW WARNING UNTIL 7 PM EST THIS EVENING FOR
NYZ009-018-036-037.
LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST THIS EVENING FOR
NYZ046.
&&
$$
SYNOPSIS...MDP
NEAR TERM...MDP
SHORT TERM...BJT
LONG TERM...BJT
AVIATION...JAB
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1136 PM CST TUE JAN 12 2016
.UPDATE...
ISSUED AT 1136 PM CST TUE JAN 12 2016
THE LATEST WATER VAPOR IMAGERY SHOWS A SHORTWAVE DIVING SOUTHEAST
FROM SOUTHERN SASKATCHEWAN...FORECAST TO MOVE INTO THE TURTLE
MOUNTAINS AND EXTEND INTO THE NORTHERN JAMES RIVER VALLEY 12Z
WEDNESDAY. REGIONAL RADAR SHOWS WEAK REFLECTIVITY`S SLIDING
THROUGH ROLETTE COUNTY. SURFACE OBSERVATIONS AT ROLLA MUNICIPAL
AIRPORT NOT INDICATING PRECIPITATION REACHING THE GROUND AS OF
THIS WRITING...BUT WITH CEILINGS AT 5000FT IT IS JUST A MATTER OF
TIME. CURRENT GRIDS HAVE THIS HANDLED WELL. A MOSTLY CLEAR SKY WAS
TAKING SHAPE IN THE WEST WITH HIGH CLOUDS ADVANCING THROUGH
CENTRAL/EASTERN MONTANA. OVERCAST CONDITIONS CENTRAL NORTH DAKOTA
WILL GRADUALLY IMPROVE TO PARTLY CLOUDY REST OF TONIGHT EXCEPT
FROM THE TURTLE MOUNTAINS INTO THE JAMES RIVER VALLEY WITH THE
ASSOCIATED SHORTWAVE MENTIONED ABOVE. MINOR UPDATES TO SKY GRIDS
WITH THE OVERALL FORECAST IN GOOD STANDING.
UPDATE ISSUED AT 929 PM CST TUE JAN 12 2016
SOME LIGHT ECHOS ON RADAR ARE STARTING TO SHOW UP OVER FAR NORTH
CENTRAL NORTH DAKOTA. FOR LATE EVENING UPDATE HAVE ADDRESSED THIS
BY STARTING LOW CHANCES FOR SNOW NOW...WHICH IS A BIT EARLIER THAN
PREVIOUS FORECAST. OTHERWISE...BESIDES ADJUSTING CLOUD COVER
TOWARDS CURRENT SATELLITE TRENDS REMAINDER OF FORECAST WAS IN GOOD
SHAPE.
UPDATE ISSUED AT 604 PM CST TUE JAN 12 2016
FOR EARLY EVENING UPDATE HAVE ADDED LOW CHANCES FOR SNOW OVER THE
FAR SOUTHWEST AS WEAK WAVE MOVES THROUGH AND SOME WEAK ECHOS ARE
SHOWING UP ON THE BOWMAN NDARB RADAR. ONLY OTHER CHANGE WAS TO
INCREASE CLOUD COVER THROUGH THE EVENING AS SATELLITE HAS MOST OF
THE AREA UNDER OVERCAST SKIES.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 245 PM CST TUE JAN 12 2016
LOW-END PRECIPITATION CHANCES AND A STARK TEMPERATURE CONTRAST
FROM NORTH CENTRAL TO SOUTHWEST ND HIGHLIGHT THE SHORT TERM.
LIGHT SNOW FROM NORTHWEST INTO SOUTH CENTRAL ND HAS BEEN ON A
STEADY WEAKENING TREND SINCE ABOUT 19 UTC...AND IS EXPECTED TO
DIMINISH FURTHER BY LATE AFTERNOON AS ASCENT DROPS OFF. WE ARE
THEN CARRYING ANOTHER SLIGHT CHANCE OF LIGHT SNOW LATE TONIGHT
FROM BOTTINEAU TOWARD RUGBY AND ROLLA OUT OF RESPECT TO A WEAK
SHORTWAVE TROUGH IN NORTHWEST FLOW ALOFT THAT WILL CLIP THAT
AREA AFTER 06 UTC.
INTERESTINGLY...BOTH THE OPERATIONAL AND EXPERIMENTAL /ESRL-RUN/
HRRR FLAVORS HAVE BEEN SIMULATING DENSE FOG DEVELOPMENT ACROSS
CENTRAL ND TONIGHT. THEY ARE ON THEIR OWN IN THIS EXPECTATION AS
NEITHER THE 12 UTC NAM-NEST OR POINT-BASED MOS GUIDANCE /MAV OR
MET OUTPUT/ SUGGEST THIS SCENARIO. CLOSER INSPECTION SHOWED THE
HRRR SIMULATIONS DEVELOP THIS FOG OVER LAKE SAKAKAWEA AND THEN
ADVECT IT DOWNSTREAM ON LIGHT WIND FIELDS. SKIN TEMPERATURES IN
THE HRRR SIMULATIONS ARE ABOVE 40 F OVER LAKE SAKAKAWEA...WHICH
MEANS THEY ARE ASSUMING MUCH MORE OPEN WATER EXISTS THAN DOES IN
REALITY. THUS...WE BELIEVE THAT THE HRRR GUIDANCE IS LIKELY
OVERZEALOUS WITH ITS EXPECTATION OF FOG AND LOW CLOUD FORMATION.
ON WEDNESDAY...STRONGER MID-LEVEL WARM AIR ADVECTION WILL OCCUR
AND PUSH 850-MB TEMPERATURES TO +2 TO +4 C SOUTH AND WEST OF THE
MISSOURI RIVER BY AFTERNOON. THE RESULT WILL BE HIGHS ABOVE 32 F
IN THOSE AREAS...CONTRASTED BY HIGHS ONLY IN THE TEENS F ACROSS
ROLETTE COUNTY. THE LOW- TO MID-LEVEL WARM FRONTAL BOUNDARY THAT
WILL SEPARATE THOSE AIR MASSES COULD SERVE AS A FOCUS FOR LIGHT
PRECIPITATION BY LATE DAY AS ANOTHER SHORTWAVE TROUGH APPROACHES
THE AREA. THE 12 UTC MULTI-MODEL CONSENSUS SUPPORTED POPS OF 20
TO 30 PERCENT OVER NORTHWEST ND BY LATE AFTERNOON...AND WE CHOSE
TO CONTINUE WITH A SLIGHT CHANCE OF LIGHT FREEZING IN THE WATFORD
CITY AND WILLISTON AREAS BASED ON EXPECTED TEMPERATURES ALOFT. WE
KEPT THE FORECAST DRY OVER SOUTH CENTRAL ND GIVEN A DRY BOUNDARY
LAYER...BUT THE 12 UTC NCEP WRF-ARW SIMULATED LIGHT PRECIPITATION
INTO THE BISMARCK AREA BY VERY LATE AFTERNOON...WHICH REPRESENTS
A VERY LOW-END...BUT NON-ZERO RISK OF LIGHT FREEZING RAIN. WE DID
NOT INCLUDE THAT IN THE OFFICIAL FORECAST AT THIS POINT FOR THAT
AREA THOUGH SINCE THE PROBABILITY OF OCCURRENCE IS VERY LOW.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 207 PM CST TUE JAN 12 2016
THE MAIN ISSUES IN THE LONG TERM ARE SNOW CHANCES FOR THE END OF
THE WEEK AND DANGEROUS COLD THIS WEEKEND.
A CLIPPER WILL APPROACH NORTH DAKOTA WEDNESDAY EVENING.
PRECIPITATION IS EXPECTED TO FORM ACROSS A PERSISTENT BAROCLINIC
ZONE BISECTING NORTH DAKOTA. THE 12 UTC MODELS ARE IN FAIRLY GOOD
AGREEMENT IN SPREADING 1 TO 2 INCHES OF SNOW ACROSS NORTHERN NORTH
DAKOTA...WITH THE HIGHEST AMOUNTS CONFINED TO THE TURTLE
MOUNTAINS. LIGHT SNOW IS EXPECTED TO BEGIN ACROSS FAR NORTHWEST
NORTH DAKOTA WEDNESDAY EVENING AND SPREAD SOUTHEAST THROUGH
WEDNESDAY NIGHT INTO THURSDAY MORNING. THE BAROCLINIC ZONE WILL
SHIFT FURTHER SOUTHWEST THURSDAY AND FRIDAY...AND THEREFORE SNOW
CHANCES WILL ALSO SHIFT FROM NORTHERN NORTH DAKOTA TO SOUTHWEST
NORTH DAKOTA. HOWEVER...WITH THESE QUICK MOVING WAVES ONLY LIGHT
QPF AMOUNTS ARE EXPECTED...SO LITTLE TO NO IMPACTS ARE
ANTICIPATED.
ANOTHER DEEP GREAT LAKES TROUGH IS EXPECTED TO FORM BY THIS
WEEKEND. THIS WILL ALLOW BITTERLY COLD ARCTIC AIR TO PUSH INTO
NORTH DAKOTA. THERE IS SOME UNCERTAINTY AS TO EXACTLY WHEN THE
SURFACE HIGH AND COLDEST AIR WILL SETTLE ACROSS NORTH DAKOTA.
HOWEVER...IT APPEARS TEMPERATURES WELL BELOW ZERO ARE
LIKELY...WITH WIND CHILLS POTENTIALLY REACHING THE 20S AND 30S
BELOW.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1136 PM CST TUE JAN 12 2016
VFR CIGS/VSBYS EXPECTED AT ALL TERMINALS THROUGH MOST OF THIS TAF
PERIOD. THE EXCEPTION WILL BE AT KISN/KMOT...BETWEEN 03Z AND 06Z
THURSDAY...AS MVFR CIGS WILL RETURN. AN AREA OF SNOW IS ALSO
POSSIBLE NEAR KISN/KMOT 06Z-12Z THURSDAY AND WILL ADDRESS THIS IN
THE NEXT TAF FORECAST.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KS
SHORT TERM...CJS
LONG TERM...AJ
AVIATION...KS
AREA FORECAST DISCUSSION...CORRECTED
NWS PORTLAND OR
946 PM PST TUE JAN 12 2016
.SYNOPSIS...THE PACIFIC NORTHWEST IS MOVING BACK INTO A WET WEATHER
REGIME WHICH WILL LAST FOR THE NEXT SEVERAL DAYS...AS SEVERAL LOW
PRESSURE AND ASSOCIATED FRONTAL SYSTEMS ARE FORECAST TO MOVE THROUGH
THE REGION. THE LATEST LOW PRESSURE SYSTEM IS MOVING UP THE PAC NW
COAST THIS EVENING...WITH STEADY RAIN THIS EVENING EXPECTED TO TAPER
TO SHOWERS BY WEDNESDAY MORNING AS A COLD FRONT SLOWLY MOVES ONSHORE.
SNOW LEVELS WILL FALL BACK BELOW THE CASCADE PASSES BEHIND THE FRONT
WEDNESDAY. THE NEXT SYSTEM IMPACTS THE REGION THURSDAY AND THURSDAY
NIGHT AND HAS THE POTENTIAL TO BRING SEVERAL INCHES OF SNOW TO THE
CASCADES. ADDITIONAL FRONTS ARE EXPECTED OVER THE WEEKEND AND EARLY
NEXT WEEK...KEEPING WET WEATHER IN THE FORECAST.
&&
.EVENING UPDATE...STEADY LIGHT TO MODERATE RAIN HAS AFFECTED THE
MAJORITY OF THE FORECAST AREA FOR MUCH OF THE DAY...ADDING UP TO
ABOUT AN INCH FOR MOST OF THE LOWLANDS AND ABOUT 2 INCHES IN THE
HIGHER TERRAIN. THIS IS BEING CAUSED BY PERSISTENT ISENTROPIC LIFT AS
WARM...MOIST AIR OVERRUNS COOLER AIR ENTRENCHED NEAR THE SURFACE. LOW
PRESSURE OFFSHORE HAS BEEN DRIVING THE SOUTHERLY FLOW ALOFT WHICH IS
PARTIALLY RESPONSIBLE FOR THE ISENTROPIC LIFT. THE INTENSITY AND
LOCATION OF THIS LOW CENTER HAVE BEEN PRETTY HARD TO PIN DOWN
OVERNIGHT...BOTH FOR FORECASTERS AND FOR THE MODELS. IT APPEARS THAT
AS OF 9 PM THE LOW CENTER IS AROUND 997 MB...ABOUT 20 TO 30 MILES
OFFSHORE FROM ASTORIA. THIS LOW BROUGHT A QUICK BUT IMPRESSIVE SURGE
OF WIND TO BUOY 46050...WITH A GUST UP TO 52 KT OR 59 MPH. HOWEVER IT
APPEARS THE EASTERLY COMPONENT TO THE SURFACE GRADIENTS HAS KEPT THE
STRONGEST SFC WINDS OFFSHORE. THE STRONGEST COASTAL GUSTS HAVE BEEN
IN THE 40-50 MPH RANGE...DESPITE 60-70 KT WINDS SHOWING UP JUST
1000-2000 FT ABOVE THE SURFACE ACCORDING TO THE ESRL ASTORIA
PROFILER. BETTER MIXING IS POSSIBLE TONIGHT AS THE COAST BRIEFLY GETS
INTO THE WARM SECTOR...BUT THE STRONGEST SOUTH TO NORTH GRADIENTS
APPEAR TO BE RATHER COMPACT AND CLOSE TO THE LOW CENTER. A SECONDARY
LOW MOVING ONSHORE NEAR THE OR/CA BORDER APPEARS TO BE ROBBING THE
OVERALL GRADIENTS A BIT...AND THUS THE STRONGEST WIND THREAT. DECIDED
TO CANCEL THE HIGH WIND WARNING FOR OUR OREGON COAST ZONES...IT WILL
STILL BE WINDY WITH 40-50 MPH GUSTS BUT WINDS SHOULD REMAIN BELOW
WARNING CRITERIA.
MEANWHILE COLD AIR REMAINS ENTRENCHED EAST OF THE CASCADE CREST...
KEEPING SNOW LEVELS FAIRLY LOW NORTH AND EAST OF MOUNT HOOD. RECEIVED
A PUBLIC REPORT OF 7 INCHES OF SNOW AT TROUT LAKE A COUPLE HOURS
AGO...AND WEBCAMS IN THE AREA SEEM TO CONFIRM THIS. ENOUGH WARM AIR
HAS MOVED IN ALOFT TO SWITCH THE PRECIPITATION TO RAIN IN THE HOOD
RIVER VALLEY...BUT TEMPS REMAIN STUBBORNLY NEAR FREEZING IN UPPER
PORTIONS OF THE VALLEY SO THERE ARE LIKELY SOME POCKETS OF FREEZING
RAIN. SOUTH OF MOUNT HOOD...SNOW LEVELS HAVE SKYROCKETED TO 6000 TO
7000 FEET...SO THE CASCADE PASSES ARE JUST EXPERIENCING RAIN AT THE
MOMENT. WILL EXTEND THE WINTER WX ADVISORY FOR THE UPPER HOOD RIVER
VALLEY UNTIL 4 AM...WHICH IS WHEN THE LAST COUPLE RUNS OF THE HRRR
MODEL SUGGEST THE STEADY PRECIPITATION WILL WIND DOWN OVER THE HOOD
RIVER VALLEY. THERE WILL PROBABLY BE LESS OF A DISTINCT BREAK IN
PRECIP OVER THE S WA CASCADES...WITH MOST MODELS SUGGESTING A
RESURGENCE OF PRECIPITATION WITH A COLD FRONT WED MORNING. THEREFORE
WE EXTENDED THE ADVISORY FOR THE S WA CASCADES UNTIL 2 PM. COLD AIR
TRAPPED IN SOME SKAMANIA COUNTY VALLEYS MAY ALSO LEAD TO SOME POCKETS
OF FREEZING RAIN THROUGH WED MORNING.
DECIDED TO ADD A SLIGHT CHANCE OF THUNDER FOR THE COAST AND COASTAL
WATERS LATER TONIGHT THROUGH WED EVENING AS THE 00Z NAM SUGGESTS
ENOUGH COLD AIR ALOFT TO DESTABILIZE THE ATMOSPHERE FOR A
THUNDERSTORM OR TWO. 04Z HRRR AND THE PREVIOUS COUPLE RUNS HAVE BEEN
SUGGESTING A BIT OF A CONVECTIVE LINE MAY DEVELOP WITH THE COLD FRONT
AS IT MOVES ONSHORE WED MORNING...ESPECIALLY FOR OUR SOUTHERN ZONES.
WE KEPT THUNDER CHANCES LIMITED TO THE COAST...BUT IT IS NOT OUT OF
THE QUESTION THAT A STRAY LIGHTNING STRIKE OR TWO MAKE IT EAST OF THE
COAST RANGE LATER TONIGHT AND WED. MADE VERY FEW CHANGES BEYOND WED
AND PREVIOUS DISCUSSION BELOW HANDLES THE NEXT SYSTEM WELL. WEAGLE
/FROM PREV DISCUSSION ISSUED 227 PM TUE JAN 12 2016/
SNOW LEVELS HAVE ALREADY RISEN ABOVE THE CASCADE PASSES EARLY THIS
AFTERNOON. THE KTTD PROFILER INDICATES SNOW LEVELS NEAR 6000 FEET.
GOVERNMENT CAMP WAS AROUND 35 DEG AND SANTIAM JCT...NEAR 4000
FEET...WAS AT 39 DEG. SNOW LEVELS FALL AGAIN WEDNESDAY AS THE UPPER
TROUGH MOVES INLAND. THERE IS SOME POTENTIAL FOR LOW-END SNOW
ADVISORY AMOUNTS IN THE CASCADES WED. GFS SHOWS ONE FINAL SHORT-WAVE
TROUGH MOVING ACROSS THU EVENING. THERE WILL BE A SHORT BREAK OR
DECREASE IN THE ACTION THU NIGHT AS THE NEXT DEVELOPING LOW TAKES
SHAPE IN THE ERN PAC. OFFSHORE LOW-LEVEL RETURNS LATE THU AND AND THU
EVENING. THIS WILL LIKELY DRIVE SNOW LEVELS LOWER THAN MODELS
SUGGEST...ESPECIALLY FOR THE S WA CASCADES...UPPER HOOD RIVER VALLEY
AND CENTRAL COLUMBIA GORGE. THIS SYSTEM MOVES INLAND LATE THU AND THU
NIGHT...WITH THE BRUNT OF IT HEADING INTO SW OREGON. SNOW LEVELS TO
REMAIN BELOW THE CASCADE PASSES WITH THIS SYSTEM WITH ADVISORY
AMOUNTS HIGHLY LIKELY. BELIEVE THE SYSTEM MOVES THROUGH TOO QUICKLY
FOR WARNING AMOUNTS. MODELS MAINTAIN SOME LINGERING PRECIP OVER MUCH
OF THE FORECAST AREA FRI MORNING DESPITE DEVELOPING 500 MB RIDGING.
THERE MAY BE A 6-12 HR DRY OR NEARLY-DRY PERIOD FRI AFTERNOON THROUGH
FRI EVENING BEFORE OVER-RUNNING FROM THE NEXT SYSTEM ARRIVES.
WEISHAAR
.LONG TERM...THE WET AND PROGRESSIVE PATTERN CONTINUES THROUGH THE
LONG TERM. GFS AND ECMWF SHOW ANOTHER SYSTEM MOVING THROUGH THE AREA
SAT. SNOW LEVELS SHOULD REMAIN AT OR JUST BELOW THE CASCADE PASSES
FOR ADDITIONAL ACCUMULATIONS. THIS SYSTEM DOES NOT LOOK QUITE AS WET
AS ITS PREDECESSORS BUT COULD STILL PRODUCE SNOW ADVISORY AMOUNTS FOR
THE CASCADES. MODELS SHOW MORE VARIANCE SUN WITH THE GFS SHOWING
ANOTHER SYSTEM. IT STAYS FAIRLY CONSOLIDATED. THE ECMWF HAS STRONGER
500 MB RIDGING OVER THE AREA WITH WARM-FRONTAL OVER-RUNNING SPREADING
ACROSS THE NRN ZONES SUN. MODELS MAINTAIN A FAIRLY PROGRESSIVE NATURE
EARLY NEXT WEEK WITH 1000-500 MB THICKNESS VALUES HOVERING AROUND 540
DM...OR CLOSE TO THE CASCADE PASSES. WEISHAAR
&&
.AVIATION...AN OCCLUDED FRONT WILL MAINTAIN RAIN AND VARIABLE
CLOUDS THROUGH WED MORNING...WITH A MIX OF FLIGHT CONDITIONS.
CONDITIONS WILL MOSTLY BE A MIX OF VFR AND MVFR...BUT BRIEF
PERIODS OF IFR CONDITIONS ARE POSSIBLE JUST ABOUT ANYWHERE. THE
RAIN WILL TURN TO SHOWERS WED AFTERNOON...AND CIGS SHOULD RISE.
EAST WINDS WILL CONTINUE TO GUSTS TO 35 KT NEAR THE GORGE THIS
EVENING....GRADUALLY DECREASING AFTER MIDNIGHT.
KPDX AND APPROACHES...MOSTLY VFR TONIGHT. CIGS WILL LIKELY LOWER
TO MVFR BY 15Z. VFR CONDITIONS WITH SHOWERS WED. E WINDS 20-25KT
TONIGHT...BECOMING S 15KT AROUND 15Z. TJ
&&
.MARINE...A LOW MOVING SOUTH TO NORTH ALONG AN OCCLUDED FRONT
BROUGHT A BURST OF SOUTHERLY GALES TO THE WATERS...AND STORM FORCE
WINDS SOUTH OF CASCADE HEAD THIS EVENING. THE WINDS WILL
DRAMATICALLY WEAKEN AROUND MIDNIGHT AS THE LOW MAKES
LANDFALL...AND WINDS WILL VEER TO THE NW. RATHER BENIGN WINDS WED
AS HIGH PRESSURE BRIEFLY RETURNS. THE THURSDAY FRONT LOOKS VERY
SIMILAR TO THE CURRENT ONE...AND MAY SEE ANOTHER COASTAL JET WITH
A BURST OF STRONG WINDS IN THE AFTERNOON OR EVENING. FORECAST
CONFIDENCE IN THE WINDS ARE HIGH ENOUGH TO ISSUE ANY WATCHES. A
COUPLE OF FRONTS WILL BRING CHANCES FOR GALES...OR POSSIBLY STORM
THURSDAY...AND FRI NIGHT THROUGH SAT.
WIND WAVES FROM THE STRONGER WINDS THIS EVENING HAS RAISED SEAS TO
18 FT SOUTH OF CASCADE HEAD...AND WILL RAPIDLY SUBSIDE TONIGHT.
SEAS WILL GENERALLY FLUCTUATE BETWEEN 10 AND 13 FT WED THROUGH THU
MORNING. WIND WAVES WILL THEN RISE WITH THE FRONT THU AFTERNOON
WITH SEAS BACK IN THE MID TO UPPER TEENS. LOWS MOVING ACROSS THE
PACIFIC LATE IN THE WEEK WILL PRODUCE LARGER SEAS THIS
WEEKEND...POSSIBLY EXCEEDING 20 FT.TJ
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...WINTER WEATHER ADVISORY UNTIL 4 AM PST WEDNESDAY FOR UPPER HOOD
RIVER VALLEY.
WA...WINTER WEATHER ADVISORY UNTIL 2 PM PST WEDNESDAY FOR SOUTH
WASHINGTON CASCADES.
PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL 1 AM PST WEDNESDAY FOR
COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR OUT 60 NM.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 10 AM PST
THURSDAY FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE
OR OUT 60 NM.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL 10 AM
PST THURSDAY.
&&
$$
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1059 PM CST TUE JAN 12 2016
.AVIATION...
ALTHOUGH THERE WAS A DIFFERENCE IN THE MODEL DATA...THE AREA MOST
CONDUCIVE FOR FOG FORMATION TONIGHT LOOKS TO BE OVER KCXO AND
KLBX. HOWEVER...THERE IS A POTENTIAL OVER MOST SITES FROM KCXO TO
JUST INLAND OF THE COAST. THE TIME PERIOD STILL LOOKS TO BE
BETWEEN 10Z AND 15Z. OTHERWISE...VFR CONDITIONS ARE EXPECTED.
40
&&
.PREV DISCUSSION... /ISSUED 818 PM CST TUE JAN 12 2016/
DISCUSSION...
CLEAR SKIES AND LIGHT WINDS COUPLED WITH A SUBTLE INCREASE IN LOW
LEVEL MOISTURE SHOULD ALLOW FOR SOME FOG FORMATION OVERNIGHT. THE
HRRR AND RAP ARE BOTH VERY AGGRESSIVE WITH FOG DEVELOPMENT OVER
THE SW ZONES LATER TONIGHT. THE SREF ENSEMBLES CONSIDERABLY LESS
BULLISH WITH FOG THREAT. 00Z SOUNDINGS FROM CRP AND LCH DON`T LOOK
TERRIBLY FAVORABLE EITHER BUT WILL ADD PATCHY FOG TO THE GRIDS
AND MENTION LOCALLY DENSE TO THE SW ZONES FOR LATE TONIGHT. IF
THE HRRR/RAP ARE CORRECT...A DENSE FOG ADVISORY MAY BE REQUIRED
LATER TONIGHT FOR AREAS SW OF HOUSTON. BUMPED MIN TEMPS UP A
DEGREE OR TWO IN A FEW SPOTS AND LOWER ALONG THE IMMEDIATE COAST.
43
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 40 63 48 64 49 / 0 10 10 30 10
HOUSTON (IAH) 41 63 49 66 50 / 0 10 10 40 20
GALVESTON (GLS) 47 62 55 62 54 / 0 10 20 50 20
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...43
AVIATION/MARINE...40
AREA FORECAST DISCUSSION...UPDATED
NWS AUSTIN/SAN ANTONIO TX
1055 PM CST TUE JAN 12 2016
.AVIATION.../06 TAF CYCLE/
VFR CONDITIONS PREVAIL AND ARE EXPECTED TO PERSIST THROUGH THE
OVERNIGHT AND INTO WEDNESDAY. THE PREVIOUSLY LEANING HIGH-END
MVFR VISIBILITIES HAVE BEEN REMOVED FOR THIS CYCLE AS BUFR
SOUNDINGS HAVE BACKED OFF FROM LOW-LEVEL SATURATION. IT STILL
APPEARS THAT SOME SHALLOW GROUND FOG COULD DEVELOP ACROSS THE
COASTAL PLAINS AND IN RIVER VALLEYS. THIS COVERAGE SHOULD BE TOO
LIMITED TO AFFECT TAF SITES AND HAVE LEFT THEM CLEAR OVERNIGHT.
WINDS ARE LIGHT AND VARIABLE CURRENTLY AND WILL REMAIN SO
OVERNIGHT. WEAK 5-10 KT WINDS WILL RESUME BY LATE MORNING
WEDNESDAY ACROSS THE REGION FROM THE SOUTH.
&&
.PREV DISCUSSION... /ISSUED 930 PM CST TUE JAN 12 2016/
UPDATE...
A CLUSTER OF UPPER LEVEL CLOUDS AHEAD OF THE NEXT UPPER LEVEL
SYSTEM FORECAST TO AFFECT THE AREA WILL KEEP OVERNIGHT LOWS A BIT
WARMER THAN PREVIOUS NIGHTS. THESE UPPER LEVEL CLOUDS WILL REMAIN
ACROSS THE AREA ON WEDNESDAY WHILE LOW LEVEL MOISTURE INCREASES
AHEAD OF A PACIFIC FRONT. WEDNESDAYS HIGH TEMPERATURES ARE
EXPECTED TO REACH THE MID 60S OVER MOST LOCATIONS. RAIN CHANCES
ARE IN STORE FOR AREAS MAINLY ALONG AND EAST OF INTERSTATE 35 ON
THURSDAY AS THE UPPER LEVEL LOW AND PACIFIC FRONT PUSHES OVER THE
AREA. DRY WEATHER CONDITIONS ARE EXPECTED ON FRIDAY WITH RAIN
CHANCES RETURNING ON SATURDAY ACROSS THE EAST AS ANOTHER PACIFIC
FRONT PUSHES OVER THE AREA.
PREV DISCUSSION... /ISSUED 550 PM CST TUE JAN 12 2016/
AVIATION.../00Z TAF CYCLE/
SKC VFR PREVAILS OVER THE REGION WITH ONLY SOME HIGH SCT250 CIRRUS
POISED TO FILTER OVER THE REGION OVERNIGHT FROM THE SOUTHWEST.
WINDS ARE LIGHT AND VARIABLE AT 5 KT OR LESS AND WILL REMAIN SO
THROUGH 12Z. ONE ASPECT THAT WILL NEED TO BE WATCHED WITH BE
SHALLOW GROUND FOG AND/OR ISOLATED PATCHY IFR CIGS NEAR 12-15Z.
HAVE PLACED 5SM BR FOR NOW TO HEDGE THIS DIRECTION BUT BUFR
SOUNDINGS AND TIME-HEIGHTS OF THE HRRR INDICATE VERY LOW-LVL
SATURATION THAT COULD RESULT IN BRIEF LOWER RESTRICTIONS. WILL
MONITOR THESE TRENDS INTO THE 06Z TAF CYCLE. OTHERWISE...VFR IS
EXPECTED TO PREVAIL WEDNESDAY.
PREV DISCUSSION... /ISSUED 306 PM CST TUE JAN 12 2016/
SHORT TERM (TONIGHT THROUGH WEDNESDAY NIGHT)...
A GRADUAL INCREASE IN MOISTURE IS EXPECTED TONIGHT AND WEDNESDAY
AS SOUTHERLY FLOW IN THE LOW-LEVELS DEVELOPS. THE SOUTHERLY FLOW
SHOULD ALLOW FOR A LITTLE MILDER OVERNIGHT LOWS TONIGHT.
HOWEVER...CAN/T RULE OUT A FEW SPOTS DROPPING TO NEAR FREEZING
ACROSS THE WESTERN HILL COUNTRY. RAIN CHANCES RETURN TO THE RIO
GRANDE PLAINS SOUTH OF EAGLE PASS AND MOST OF THE COASTAL PLAINS
WEDNESDAY NIGHT AS AN UPPER TROUGH APPROACHES FROM THE WEST. ONLY
LIGHT AMOUNTS ARE EXPECTED AND WE/LL KEEP RAIN CHANCES IN THE
SLIGHT CHANCE CATEGORY (20%) FOR NOW AS DEEP LAYER MOISTURE AND
LIFT WILL BE LACKING.
LONG TERM (THURSDAY THROUGH TUESDAY)...
RAIN CHANCES CONTINUE ON THURSDAY FOR AREAS ALONG AND EAST OF I-35
AS THE ABOVE MENTIONED UPPER LEVEL TROUGH MOVES ACROSS SOUTHERN
TEXAS. WE/LL ALSO CONTINUE TO MENTION THE CHANCE FOR ISOLATED
THUNDERSTORMS EAST OF A TAYLOR TO FLORESVILLE LINE WITH SOME
MEAGER ELEVATED INSTABILITY MOVING IN WITH THE UPPER TROUGH. THE
UPPER TROUGH AXIS MOVES TO OUR EAST THURSDAY NIGHT...BRINGING AN
END TO RAIN CHANCES. A PACIFIC COLD FRONT WILL ALSO BEGIN TO MOVE
THROUGH THE REGION THURSDAY NIGHT BRINGING MUCH DRIER AIR TO SOUTH
CENTRAL TEXAS. DRY WEATHER IS ANTICIPATED FOR ALL AREAS ON FRIDAY
BEFORE ANOTHER COLD FRONT MOVES THROUGH SATURDAY AFTERNOON. THE
COLD FRONT ON SATURDAY WILL ALSO BE ACCOMPANIED BY A FAIRLY
COMPACT AND FAST MOVING UPPER TROUGH. THIS WILL LIKELY LEAD TO
WINDY CONDITIONS ACROSS THE REGION ON SATURDAY. MOISTURE RETURN
AHEAD OF THIS FRONT WILL BE LACKING AND FOR NOW... WE/LL ONLY
MENTION A SLIGHT CHANCE FOR SHOWERS EAST OF A GEORGETOWN TO KARNES
CITY LINE. THE MEDIUM RANGE MODELS CONTINUE TO SHOW SOME
DISAGREEMENT WITH THE WEATHER PATTERN EARLY NEXT WEEK. IT DOES
APPEAR THAT WE/LL BE A LITTLE DRIER THAN PREVIOUS MODELS INDICATED
AS MOISTURE RETURN AHEAD OF THE NEXT COLD FRONT WILL BE LACKING.
WE/LL KEEP A LOW CHANCE FOR SHOWERS EAST OF I-35 AND GO WITH A DRY
FORECAST ELSEWHERE.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 41 64 47 65 47 / 0 0 10 20 10
AUSTIN BERGSTROM INTL AIRPORT 36 63 44 65 45 / 0 0 20 20 10
NEW BRAUNFELS MUNI AIRPORT 38 63 46 66 45 / 0 0 20 20 10
BURNET MUNI AIRPORT 38 63 43 64 44 / 0 0 - 10 -
DEL RIO INTL AIRPORT 40 63 44 67 43 / 0 0 - 0 0
GEORGETOWN MUNI AIRPORT 37 63 44 65 46 / 0 0 - 20 10
HONDO MUNI AIRPORT 38 63 45 66 43 / 0 0 10 10 0
SAN MARCOS MUNI AIRPORT 38 63 45 65 46 / 0 0 20 20 10
LA GRANGE - FAYETTE REGIONAL 40 64 48 66 50 / 0 0 20 40 10
SAN ANTONIO INTL AIRPORT 40 63 47 65 47 / 0 0 20 20 -
STINSON MUNI AIRPORT 41 63 48 65 46 / 0 0 20 20 -
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...ALLEN
SYNOPTIC/GRIDS...17
PUBLIC SERVICE/DATA COLLECTION...30
AREA FORECAST DISCUSSION
NWS JACKSON KY
1006 AM EST WED JAN 13 2016
.UPDATE...
ISSUED AT 1006 AM EST WED JAN 13 2016
BLENDED MORNING OBS INTO THE FORECAST GRIDS AND UPDATED SKY
CONDITIONS THROUGH THIS EVENING BASED ON LATEST MODEL DATA.
HOWEVER...THERE ARE NO SUBSTANTIAL CHANGES TO THE FORECAST.
UPDATE ISSUED AT 750 AM EST WED JAN 13 2016
DID A QUICK UPDATE MAINLY TO FINE TUNE THE TD AND T GRIDS PER THE
LATEST OBS AND TRENDS. THESE HAVE BEEN SENT TO THE NDFD AND WEB
SERVERS.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 335 AM EST WED JAN 13 2016
07Z SFC ANALYSIS SHOWS COLD HIGH PRESSURE BUILDING INTO KENTUCKY.
THIS IS HELPING TO SETTLE THE WINDS AND HAS CLEARED THE SKY. AS A
RESULT...TEMPERATURES ARE DROPPING TOWARD 10 DEGREES IN THE
EASTERN VALLEYS AND NORTHWEST PARTS OF THE AREA WHILE MID AND
UPPER TEENS ARE FOUND ON THE RIDGES AND THROUGH THE CUMBERLAND
VALLEY. DEW POINTS...MEANWHILE ARE IN THE SINGLE DIGITS MOST
PLACES. THE SNOW SQUALLS OF TUESDAY AFTERNOON SPARED MOST
LOCATIONS GENERALLY SOUTH OF THE MOUNTAIN PARKWAY BUT DID MANAGE
TO LAY DOWN A LAYER OF SNOW OF VARYING THICKNESS NORTH OF THE
HIGHWAY...AND PARTICULARLY FOR POINTS ALONG AND NORTH OF
INTERSTATE 64. THESE PLACES WILL RADIATE EXTRA WELL FOR THE REST
OF THE NIGHT WITH SOME SINGLE DIGITS CERTAINLY POSSIBLE BY DAWN.
WILL LIKELY DO SOME FINAL ADJUSTMENTS TEMPS IN THESE PLACES
BEFORE GRID ISSUANCE.
THE MODELS ARE IN EXCELLENT AGREEMENT ALOFT THROUGH THE SHORT
TERM PORTION OF THE FORECAST. THEY ALL DEPICT A CLUSTER OF WEAK
MID LEVEL WAVES PASSING THROUGH THE OHIO VALLEY TODAY AND TONIGHT
IN NORTHWEST FLOW...EVEN AS THE HEIGHTS CONTINUE TO REBOUND.
EASTERN KENTUCKY WILL GET INTO SOME SLIGHT RIDGING ON THURSDAY
AHEAD OF A STILL UNCONSOLIDATED TROUGH MOVING INTO THE CENTRAL
PLAINS AND ANOTHER WEAK ONE LIFTING NORTHEAST FROM NORTHERN
MEXICO IN THE SOUTHERN STREAM. LOOK FOR THESE TO START TO INTERACT
AND BRING A CHANCE OF RAIN TO THE AREA EARLY IN THE EXTENDED. IN
THE MEANTIME...THOUGH...A QUIET MID LEVELS AND DRY AIR IN PLACE
WILL KEEP THE WEATHER RATHER BENIGN THROUGH THURSDAY. HAVE FAVORED
THE HIGHER RESOLUTION GUIDANCE FROM THE HRRR AND NAM12 FOR
FORECAST DETAILS.
SENSIBLE WEATHER WILL FEATURE A CHILLY START WITH TEMPERATURES IN
THE TEENS AND SINGLE DIGITS THIS MORNING ALONG WITH WIND CHILLS
NEAR ZERO AT TIMES. HOWEVER...PLENTY OF SUNSHINE IN THE MORNING
WILL HELP THE MERCURY REBOUND TO ABOVE FREEZING AND INTO THE MID
30S DURING THE AFTERNOON...FOR MOST PLACES WITHOUT A SNOW PACK.
LOCATIONS ALONG AND NORTH OF INTERSTATE 64 WILL STRUGGLE TO SEE
FREEZING TEMPS...THOUGH. A PASSING AREA OF LOW PRESSURE TO THE
NORTH WILL BRING SOME MID LEVEL CLOUDS TO THE NORTHERN PARTS OF
THE CWA THIS AFTERNOON AND EVENING BUT NO PCPN OR FLURRIES ARE
EXPECTED FROM THESE. MILDER TEMPERATURES ARE ON TAP FOR TONIGHT AS
WARMER AIR STARTS TO MOVE IN AND THE HIGH RETREATS TO THE EAST.
THE WARM-UP WILL BE MOST PRONOUNCED ON THURSDAY WHEN SOUTHWEST
WINDS KICK IN SUPPORTING TEMPERATURES TOPPING OUT IN THE UPPER 40S
AND LOWER 50S.
AGAIN USED THE SHORTBLEND AS A STARTING POINT FOR TEMPS AND
DEW POINTS THROUGH THE EVENING FOLLOWED BY THE SUPERBLEND. DID
MAKE SOME ADJUSTMENTS TONIGHT TO HIGHLIGHT A DECENT RIDGE TO
VALLEY TEMPERATURE SPLIT. AS FOR POPS...THEY ARE BASICALLY LOW
SINGLE DIGITS OR NEAR ZERO THROUGH THE SHORT TERM...IN LINE WITH
MOS GUIDANCE.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 335 AM EST WED JAN 13 2016
BIG STORY TO BEGIN THIS PERIOD WILL BE THE CONTINUED ABOVE AVERAGE
TEMPERATURES. WE BEGIN THE PERIOD WITH SURFACE HIGH PARKED TO OUR
SOUTHEAST AND IN THE WARM SECTOR. THIS WILL BE AHEAD OF DEEPENING
UPPER LEVEL TROUGH ACROSS THE NORTHERN CENTRAL PLAINS. THAT SAID
THIS WILL BE THE NEXT WEATHER MAKER TO END THE WORK WEEK AND START
OF THE WEEKEND. THIS UPPER LEVEL TROUGH WILL CONTINUE TO DIG AS
IT MOVES EAST AND PIVOTS INTO THE MID ATLANTIC...ALL WHILE
BECOMING NEGATIVELY TILTED. THERE ARE SOME ISSUES THAT WILL HAVE
TO BE LOOKED AT WITH THIS SYSTEM MORE AS WE GET CLOSER. THE FIRST
IS AS THE TROUGH NEGATIVELY TILTS ALONG THE MID ATLANTIC AND A
300MB JET STREAK PUNCHES IN FROM THE GULF OF MEXICO...A SURFACE
LOW WILL CONTINUE TO DEEPEN ACROSS THE SE. THIS COULD PLAY A ROLE
IN CUTTING OFF SOME OF THE MOISTURE WITH THIS SYSTEM AND WILL
HAVE TO BE RESOLVED FURTHER...THE NAM AND GFS HAVE THE MOST
CONSISTENCY WITH BETTER QPF NW ACROSS NORTH CENTRAL KY. EVEN SO
KEPT CLOSE TO PREVIOUS FORECAST IN TERMS OF POPS GIVEN THE FACT
THAT WE WILL PROBABLY SEE SOMETHING MEASURABLE. NOW THE BEST LIFT
WILL BE IN THE EVENING HOURS ON FRIDAY AND LIFT TRAILS OFF FROM
THERE.
THE NEXT ISSUE WILL BE TRANSITION FROM RAIN TO SNOW
OVERNIGHT...RIGHT NOW TRANSITION IN THE FAR WEST NEAR DAWN AND
MOVE THAT TRANSITION THROUGH THE MORNING. IT DOES LOOK LIKE MUCH
OF THIS SHOULD REMAIN SNOW SHOWER ON SATURDAY. OVERALL NOT LOOKING
AT MUCH IN TERMS OF ACCUMULATION GIVEN THE WARM TEMPS PRIOR. AFTER
THIS WE ARE POISED TO MOVE BACK TO THE MUCH COLDER AIR AFTER THE
QUICK WARM UP. RIGHT NOW MODELS ARE HAVING TROUBLE RESOLVING WHAT
WILL HAPPEN HERE SUNDAY...BUT SEEMS LIKE THEY ARE CATCHING ON TO
THE FACT THAT ANOTHER ARCTIC FRONT WILL PASS ACROSS THE REGION.
THAT SAID DID LEAN TOWARD THE BLEND FOR THIS WHICH BRINGS SOME
SLIGHT TO CHANCE POPS INTO THE PICTURE...ANY SNOW ACCUM IS
EXPECTED TO REMAIN LIGHT. THAT SAID SOME MUCH COLD AIR ARRIVES
INTO THE REGION BEHIND THIS FRONT...WITH 850MB TEMPS IN THE MINUS
20 RANGE NOT OUT OF THE QUESTION. MONDAY COULD BE THE FIRST TIME
THIS WINTER SEASON THAT WE ONLY MAKE IT INTO THE MID TO UPPER 20S
FOR MOST. OVERNIGHT LOWS FOR BOTH SUNDAY AND MONDAY NIGHT WILL
LIKELY BE IN THE TEENS WITH SINGLE DIGITS CERTAINLY NOT OUT OF THE
REALM OF POSSIBILITY PARTICULARLY MONDAY NIGHT. ALL THIS SAID
WITH SURFACE HIGH BUILDING THE FIRST PART OF YOUR WORK WEEK LOOKS
WELL BELOW AVERAGE TEMP WISE...BUT WILL REMAIN DRY.
OVERALL STUCK WITH MODEL BLEND THROUGH THE PERIOD...DID GO HIGHER
THAN BLEND IN LINE WITH PREVIOUS FORECAST FOR THE WEEKEND SYSTEM.
ALSO TEMP WISE ON FRIDAY DID BUMP THAT UP JUST GIVEN THE STRONG
LLJ THAT KICKS INTO GEAR IN THE AFTERNOON. ALSO KEPT THE FORECAST
DRY FOR MONDAY WITH MOST OF THE MODELS NOW DEPICTING THAT THOUGHT.
DID ADD SOME RIDGE/VALLEY SPLITS AT THE END OF THE PERIOD
PARTICULARLY AS HIGH CRESTS ACROSS THE REGION.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 725 AM EST WED JAN 13 2016
CONDITIONS WILL BE VFR THROUGH THE PERIOD AS AN AREA OF HIGH
PRESSURE MOVES IN. THIS WILL CONTINUE THE LIGHT WINDS...AT LESS
THAN 10 KNOTS...GENERALLY FROM THE WEST TO SOUTHWEST.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...HAL
SHORT TERM...GREIF
LONG TERM...DJ
AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
750 AM EST WED JAN 13 2016
.UPDATE...
ISSUED AT 750 AM EST WED JAN 13 2016
DID A QUICK UPDATE MAINLY TO FINE TUNE THE TD AND T GRIDS PER THE
LATEST OBS AND TRENDS. THESE HAVE BEEN SENT TO THE NDFD AND WEB
SERVERS.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 335 AM EST WED JAN 13 2016
07Z SFC ANALYSIS SHOWS COLD HIGH PRESSURE BUILDING INTO KENTUCKY.
THIS IS HELPING TO SETTLE THE WINDS AND HAS CLEARED THE SKY. AS A
RESULT...TEMPERATURES ARE DROPPING TOWARD 10 DEGREES IN THE
EASTERN VALLEYS AND NORTHWEST PARTS OF THE AREA WHILE MID AND
UPPER TEENS ARE FOUND ON THE RIDGES AND THROUGH THE CUMBERLAND
VALLEY. DEWPOINTS...MEANWHILE ARE IN THE SINGLE DIGITS MOST
PLACES. THE SNOW SQUALLS OF TUESDAY AFTERNOON SPARED MOST
LOCATIONS GENERALLY SOUTH OF THE MOUNTAIN PARKWAY BUT DID MANAGE
TO LAY DOWN A LAYER OF SNOW OF VARYING THICKNESS NORTH OF THE
HIGHWAY...AND PARTICULARLY FOR POINTS ALONG AND NORTH OF
INTERSTATE 64. THESE PLACES WILL RADIATE EXTRA WELL FOR THE REST
OF THE NIGHT WITH SOME SINGLE DIGITS CERTAINLY POSSIBLE BY DAWN.
WILL LIKELY DO SOME FINAL ADJUSTMENTS TEMPS IN THESE PLACES
BEFORE GRID ISSUANCE.
THE MODELS ARE IN EXCELLENT AGREEMENT ALOFT THROUGH THE SHORT
TERM PORTION OF THE FORECAST. THEY ALL DEPICT A CLUSTER OF WEAK
MID LEVEL WAVES PASSING THROUGH THE OHIO VALLEY TODAY AND TONIGHT
IN NORTHWEST FLOW...EVEN AS THE HEIGHTS CONTINUE TO REBOUND.
EASTERN KENTUCKY WILL GET INTO SOME SLIGHT RIDGING ON THURSDAY
AHEAD OF A STILL UNCONSOLIDATED TROUGH MOVING INTO THE CENTRAL
PLAINS AND ANOTHER WEAK ONE LIFTING NORTHEAST FROM NORTHERN
MEXICO IN THE SOUTHERN STREAM. LOOK FOR THESE TO START TO INTERACT
AND BRING A CHANCE OF RAIN TO THE AREA EARLY IN THE EXTENDED. IN
THE MEANTIME...THOUGH...A QUIET MID LEVELS AND DRY AIR IN PLACE
WILL KEEP THE WEATHER RATHER BENIGN THROUGH THURSDAY. HAVE FAVORED
THE HIGHER RESOLUTION GUIDANCE FROM THE HRRR AND NAM12 FOR
FORECAST DETAILS.
SENSIBLE WEATHER WILL FEATURE A CHILLY START WITH TEMPERATURES IN
THE TEENS AND SINGLE DIGITS THIS MORNING ALONG WITH WIND CHILLS
NEAR ZERO AT TIMES. HOWEVER...PLENTY OF SUNSHINE IN THE MORNING
WILL HELP THE MERCURY REBOUND TO ABOVE FREEZING AND INTO THE MID
30S DURING THE AFTERNOON...FOR MOST PLACES WITHOUT A SNOW PACK.
LOCATIONS ALONG AND NORTH OF INTERSTATE 64 WILL STRUGGLE TO SEE
FREEZING TEMPS...THOUGH. A PASSING AREA OF LOW PRESSURE TO THE
NORTH WILL BRING SOME MID LEVEL CLOUDS TO THE NORTHERN PARTS OF
THE CWA THIS AFTERNOON AND EVENING BUT NO PCPN OR FLURRIES ARE
EXPECTED FROM THESE. MILDER TEMPERATURES ARE ON TAP FOR TONIGHT AS
WARMER AIR STARTS TO MOVE IN AND THE HIGH RETREATS TO THE EAST.
THE WARMUP WILL BE MOST PRONOUNCED ON THURSDAY WHEN SOUTHWEST
WINDS KICK IN SUPPORTING TEMPERATURES TOPPING OUT IN THE UPPER 40S
AND LOWER 50S.
AGAIN USED THE SHORTBLEND AS A STARTING POINT FOR TEMPS AND
DEWPOINTS THROUGH THE EVENING FOLLOWED BY THE SUPERBLEND. DID MAKE
SOME ADJUSTMENTS TONIGHT TO HIGHLIGHT A DECENT RIDGE TO VALLEY
TEMPERATURE SPLIT. AS FOR POPS...THEY ARE BASICALLY LOW SINGLE
DIGITS OR NEAR ZERO THROUGH THE SHORT TERM...IN LINE WITH MOS
GUIDANCE.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 335 AM EST WED JAN 13 2016
BIG STORY TO BEGIN THIS PERIOD WILL BE THE CONTINUED ABOVE AVERAGE
TEMPERATURES. WE BEGIN THE PERIOD WITH SURFACE HIGH PARKED TO OUR
SOUTHEAST AND IN THE WARM SECTOR. THIS WILL BE AHEAD OF DEEPENING
UPPER LEVEL TROUGH ACROSS THE NORTHERN CENTRAL PLAINS. THAT SAID
THIS WILL BE THE NEXT WEATHER MAKER TO END THE WORK WEEK AND START
OF THE WEEKEND. THIS UPPER LEVEL TROUGH WILL CONTINUE TO DIG AS
IT MOVES EAST AND PIVOTS INTO THE MID ATLANTIC...ALL WHILE
BECOMING NEGATIVELY TILTED. THERE ARE SOME ISSUES THAT WILL HAVE
TO BE LOOKED AT WITH THIS SYSTEM MORE AS WE GET CLOSER. THE FIRST
IS AS THE TROUGH NEGATIVELY TILTS ALONG THE MID ATLANTIC AND A
300MB JET STREAK PUNCHES IN FROM THE GULF OF MEXICO...A SURFACE
LOW WILL CONTINUE TO DEEPEN ACROSS THE SE. THIS COULD PLAY A ROLE
IN CUTTING OFF SOME OF THE MOISTURE WITH THIS SYSTEM AND WILL
HAVE TO BE RESOLVED FURTHER...THE NAM AND GFS HAVE THE MOST
CONSISTENCY WITH BETTER QPF NW ACROSS NORTH CENTRAL KY. EVEN SO
KEPT CLOSE TO PREVIOUS FORECAST IN TERMS OF POPS GIVEN THE FACT
THAT WE WILL PROBABLY SEE SOMETHING MEASURABLE. NOW THE BEST LIFT
WILL BE IN THE EVENING HOURS ON FRIDAY AND LIFT TRAILS OFF FROM
THERE.
THE NEXT ISSUE WILL BE TRANSITION FROM RAIN TO SNOW
OVERNIGHT...RIGHT NOW TRANSITION IN THE FAR WEST NEAR DAWN AND
MOVE THAT TRANSITION THROUGH THE MORNING. IT DOES LOOK LIKE MUCH
OF THIS SHOULD REMAIN SNOW SHOWER ON SATURDAY. OVERALL NOT LOOKING
AT MUCH IN TERMS OF ACCUMULATION GIVEN THE WARM TEMPS PRIOR. AFTER
THIS WE ARE POISED TO MOVE BACK TO THE MUCH COLDER AIR AFTER THE
QUICK WARM UP. RIGHT NOW MODELS ARE HAVING TROUBLE RESOLVING WHAT
WILL HAPPEN HERE SUNDAY...BUT SEEMS LIKE THEY ARE CATCHING ON TO
THE FACT THAT ANOTHER ARCTIC FRONT WILL PASS ACROSS THE REGION.
THAT SAID DID LEAN TOWARD THE BLEND FOR THIS WHICH BRINGS SOME
SLIGHT TO CHANCE POPS INTO THE PICTURE...ANY SNOW ACCUM IS
EXPECTED TO REMAIN LIGHT. THAT SAID SOME MUCH COLD AIR ARRIVES
INTO THE REGION BEHIND THIS FRONT...WITH 850MB TEMPS IN THE MINUS
20 RANGE NOT OUT OF THE QUESTION. MONDAY COULD BE THE FIRST TIME
THIS WINTER SEASON THAT WE ONLY MAKE IT INTO THE MID TO UPPER 20S
FOR MOST. OVERNIGHT LOWS FOR BOTH SUNDAY AND MONDAY NIGHT WILL
LIKELY BE IN THE TEENS WITH SINGLE DIGITS CERTAINLY NOT OUT OF THE
REALM OF POSSIBILITY PARTICULARLY MONDAY NIGHT. ALL THIS SAID
WITH SURFACE HIGH BUILDING THE FIRST PART OF YOUR WORK WEEK LOOKS
WELL BELOW AVERAGE TEMP WISE...BUT WILL REMAIN DRY.
OVERALL STUCK WITH MODEL BLEND THROUGH THE PERIOD...DID GO HIGHER
THAN BLEND INLINE WITH PREVIOUS FORECAST FOR THE WEEKEND SYSTEM.
ALSO TEMP WISE ON FRIDAY DID BUMP THAT UP JUST GIVEN THE STRONG
LLJ THAT KICKS INTO GEAR IN THE AFTERNOON. ALSO KEPT THE FORECAST
DRY FOR MONDAY WITH MOST OF THE MODELS NOW DEPICTING THAT THOUGHT.
DID ADD SOME RIDGE/VALLEY SPLITS AT THE END OF THE PERIOD
PARTICULARLY AS HIGH CRESTS ACROSS THE REGION.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 725 AM EST WED JAN 13 2016
CONDITIONS WILL BE VFR THROUGH THE PERIOD AS AN AREA OF HIGH
PRESSURE MOVES IN. THIS WILL CONTINUE THE LIGHT WINDS...AT LESS
THAN 10 KNOTS...GENERALLY FROM THE WEST TO SOUTHWEST.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GREIF
SHORT TERM...GREIF
LONG TERM...DJ
AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
655 AM EST WED JAN 13 2016
.SYNOPSIS...
HEAVY LAKE EFFECT SNOW WILL CONTINUE TODAY IN PARTS OF CENTRAL NEW
YORK DOWNWIND OF LAKE ONTARIO...ESPECIALLY THE SYRACUSE METRO
AREA. THE REST OF THE REGION WILL BE COLD AND BRISK WITH SCATTERED
SNOW SHOWERS OR FLURRIES. LIGHT SNOW IS POSSIBLE WITH ANOTHER CLIPPER
SYSTEM LATE TONIGHT INTO THURSDAY. A STRONGER SYSTEM IS EXPECTED FRIDAY
NIGHT THROUGH SATURDAY NIGHT WITH A MIX OF RAIN AND SNOW POSSIBLE.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
410 AM UPDATE...
HEAVY LAKE EFFECT SNOW IS ONGOING IN PARTS OF CENTRAL NEW YORK. AS
IS TYPICAL...THE BAND /OR AT TIMES BANDS/ IS FLUCTUATING IN
PLACEMENT BY THE HOUR. THIS IS OCCURRING WITH EACH PASSING RIPPLE
EMBEDDED WITHIN THE FLOW ON THE BACK SIDE OF THE UPPER TROUGH THAT
IS GRADUALLY LIFTING NORTHEAST. 1 TO 2 INCH PER HOUR SNOWFALL
RATES WILL CONTINUE WITHIN THE HEAVIEST BANDS EARLY THIS
MORNING...NOW SLAMMING THE SYRACUSE METRO AREA EAST TO ABOUT
VERONA...TO SOUTH OF UTICA. LOCAL CONDITIONS WILL VARY WIDELY WITH
ABRUPT NEAR WHITE-OUT CONDITIONS POSSIBLE AT TIMES. WEST WIND WILL
ALSO STILL GUST TO 30 MPH THROUGH THE MORNING WHICH WILL TEND TO
DRIFT THE DRY AND FLUFFY SNOW. THIS WILL MAKE IT A CHALLENGE TO
KEEP ROADS CLEAR...ESPECIALLY NORTH-SOUTH ORIENTED ROUTES.
AN INTERRUPTION IN INTENSITY MAY OCCUR AROUND MID MORNING...BEFORE
THE BAND REINVIGORATES EARLY AFTERNOON WHILE SHIFTING GRADUALLY
NORTH AND CATCHING A LONGER FETCH DOWN THE LENGTH OF LAKE ONTARIO.
THUS FAR...A TOO-FAR-SOUTHWARD BIAS HAS BEEN DEPICTED BY ARW NMM
HRRR AND RUC MODELS...WHICH HAS BEEN OBSERVED TO BE COMMON WITH
LAKE ONTARIO LAKE EFFECT EVENTS IN THE PAST. I HAVE CONTINUED TO
LEAN ON THE CANADIAN AND TO A LESSER DEGREE THE NAM FOR
EXPECTATIONS OF BAND PLACEMENT. THAT BEING SAID...THERE IS SOME
SORT OF SMALL MCV/VORTICITY FEATURE THAT WAS OBSERVED CROSSING
LAKE HURON TO THE ONTARIO PENINSULA...AND NOW GETTING INTO FAR
WESTERN LAKE ONTARIO. I SUSPECT THIS IS WHAT MAY CAUSE THE LAKE
EFFECT TO LOSE A LITTLE ORGANIZATION LATER THIS MORNING...WHICH
THE LATEST 06Z NAM ALSO SEEMS TO BE LATCHING ON.
EARLY THIS AFTERNOON LAKE EFFECT SHOULD BE AGAIN PRETTY STOUT
ALONG THE NY THRUWAY AT FIRST...BUT LIFTING NORTHWARD WITH TIME.
IT SHOULD BE NORTH OF SYRACUSE BY MID AFTERNOON...NORTH OF UTICA
BY MID-TO-LATE AFTERNOON...AND THEN EXIT NORTHERN ONEIDA COUNTY
EARLY EVENING.
FOR THE REST OF THE REGION...GENERALLY JUST A COLD BRISK DAY WITH
SCATTERED SNOW SHOWERS AND FLURRIES...MAINLY TWIN TIERS NORTHWARD.
TEMPERATURES WILL PRETTY MUCH HOLD IN THE UPPER TEENS-LOWER 20S.
LAKE ERIE BANDS WILL AT TIMES EXTEND ACROSS THE CENTRAL TWIN
TIERS TO PROVIDE LIGHT DUSTINGS OF SNOW...WHICH THE WIND WILL
EASILY PICK UP AND BLOW AROUND. THERE COULD BE AN INCH OR TWO
ACCUMULATION ESPECIALLY STEUBEN-YATES- SCHUYLER. T
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/...
LAKE ONTARIO BAND WILL SHIFT NORTH OF THE AREA THIS EVENING...BUT
ALREADY IN THIS BUSY PATTERN...THE WARM AIR ADVECTION SIDE OF
ANOTHER CLIPPER WILL MOVE IN LATE TONIGHT INTO THURSDAY MORNING.
THIS COULD PROVIDE FOR A QUICK DUSTING TO INCH OF VERY LIGHT SNOW
FOR A GOOD CHUNK OF THE AREA. THE SURFACE LOW OF THE CLIPPER WILL
PASS TO OUR NORTH...AND THE ASSOCIATED COLD FRONT WILL PRETTY MUCH
WASH OUT IN OUR VICINITY THURSDAY NIGHT WITH LITTLE IMPACT EXCEPT
PERHAPS SPOTTY FLURRIES.
ON FRIDAY...WHAT IS LEFT OF THE CLIPPER FRONTAL ZONE WILL
EFFECTIVELY TURN BACK INTO A WARM FRONT AND LIFT OUT OF THE
AREA...AS SOUTHWEST FLOW DEVELOPS WELL AHEAD OF A STRONGER LOW
THAT WILL MOVE INTO THE WESTERN GREAT LAKES. THE RESULTING WARM
AIR ADVECTION WILL BOOST TEMPERATURES INTO UPPER 30S-LOWER 40S
FRIDAY...WHICH APPEARS TO BE MAINLY DRY.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
STRONG DUAL LOW SYSTEM MOVES INTO THE NORTHEAST WITH A WARM
SECTOR AHEAD OF THE LOW ALLOWING FOR THE POTENTIAL OF MIXED
PRECIPITATION FRIDAY NIGHT AND SATURDAY. THE SYSTEM LIFTS TO THE
E/NE LATE SATURDAY AND ANOTHER COLD ARCTIC AIR MASS DROPS IN FROM
THE NW AND CHANGES THE PRECIP OVER TO ALL SNOW. SOME ACCUMULATION
ON THE BACK SIDE OF THE SYSTEM IS POSSIBLE.
THE INFLUX OF ANOTHER ARCTIC AIR MASS AND A W/NWLY FLOW REGIME
WILL ALLOW FOR A PERIOD OF LAKE EFFECT SNOW SHOWERS SUNDAY NIGHT
THROUGH TUESDAY. SIGNIFICANT SNOWFALL ACCUMULATIONS ARE POSSIBLE.
COOL TEMPERATURES ARE EXPECTED THURSDAY WITH HIGHS IN THE MID TO
UPPER 20S AND LOWS IN THE TEENS AND SINGLE DIGITS. A BRIEF PERIOD
OF MILD TEMPERATURES IS ANTICIPATED FRIDAY AND SATURDAY WITH HIGHS
IN THE MID TO UPPER 30S AND LOWS IN THE 20S. A COLD AIR MASS WILL
DROP IN LATE IN THE WEEKEND AND REMAIN IN PLACE INTO EARLY NEXT
WEEK WITH HIGHS IN THE 20S AND LOWS IN THE TEENS.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
HEAVY LAKE EFFECT SNOW WILL AFFECT KSYR-KRME WITH HIGHLY VARIABLE...AND
RESTRICTIVE FLIGHT CONDITIONS THIS MORNING. CONDITIONS ARE EXPECTED
TO IMPROVE TO VFR-MVFR THIS AFTERNOON AS SNOW SQUALLS LIFT NORTHEAST.
ELSEWHERE...GENERALLY BKN VFR CEILINGS WITH OCCASIONAL SNOW
SHOWERS BRINGING LESS THAN AN HOUR OF IFR VSBY/MVFR CIG TO THE
CENTRAL NEW YORK AIRPORTS AT ANY TIME. DID NOT COMPLICATE THE TAFS WITH
THESE INTERMITTENT RESTRICTIONS...ALTHOUGH PILOTS SHOULD BE AWARE
THAT IMC COULD QUICKLY DEVELOP WITHIN THE LOCAL PATTERN.
GOOD TO GO WITH VFR AT KAVP.
GUSTY WEST-NORTHWEST WINDS 15-30 KTS THIS MORNING EASES TO 5-15
KTS AND BACKS SOUTHWEST TONIGHT.
.OUTLOOK...
WED NGT...MVFR-IFR. PERIODS OF LIGHT SNOW.
THURS-FRI...MAINLY VFR.
SAT...MVFR/IFR IN RAIN/SNOW.
SUN...MVFR/IFR POSSIBLE SNOW SHOWERS.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...LAKE EFFECT SNOW WARNING UNTIL 7 PM EST THIS EVENING FOR
NYZ009-018-036-037.
LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST THIS EVENING FOR
NYZ046.
&&
$$
SYNOPSIS...MDP
NEAR TERM...MDP
SHORT TERM...MDP
LONG TERM...BJT
AVIATION...JAB
AREA FORECAST DISCUSSION
NWS BISMARCK ND
953 AM CST WED JAN 13 2016
.UPDATE...
ISSUED AT 953 AM CST WED JAN 13 2016
NO REAL CHANGE WITH THIS UPDATE...THOUGH WE DID UTILIZE A TIME-
LAGGED ENSEMBLE OF SHORT-RANGE MODEL GUIDANCE TO SLIGHTLY ALTER
HOURLY POPS LATE THIS AFTERNOON INTO THE EVENING. A TIME-LAGGED
ENSEMBLE OF THE LAST 3 RAP RUNS ACTUALLY SUGGESTS THE MELTING
LAYER ALOFT MAY NOT BE QUITE WARM ENOUGH FOR LIGHT FREEZING RAIN
POTENTIAL IN NORTHWEST ND LIKE WE HAVE ADVERTISED...BUT WE WILL
CERTAINLY KEEP IT IN THE FORECAST AS PRECIPITATION-TYPE ALGORITHM
OUTPUT FROM THE RAP AND OTHER GUIDANCE STILL SUPPORTS THE CHANCE.
UPDATE ISSUED AT 621 AM CST WED JAN 13 2016
NO SIGNIFICANT UPDATES THIS MORNING OTHER THAN TEMPERATURES. A
PATCH OF CLEAR SKIES ACROSS CENTRAL NORTH DAKOTA HAS ALLOWED
TEMPERATURES TO FALL INTO THE SINGLE DIGITS WHILE CLOUDS
ASSOCIATED WITH A QUICK MOVING SHORTWAVE IN EASTERN PORTION OF
CENTRAL NORTH DAKOTA HAVE CAUSED TEMPERATURES TO RISE THERE FROM
EARLIER LOWS IN THE SINGLE DIGITS. FARTHER WEST...MORE MILD AIR
HAS MOVED INTO THE FAR WEST WITH TEMPERATURES GENERALLY IN THE
TEENS NORTHWEST TO 20S SOUTHWEST. LIGHT SNOW HAS ENDED OVER
EASTERN PORTIONS OF CENTRAL NORTH DAKOTA. WILL UPDATE CURRENT LOW
TEMPERATURES AND BLEND THROUGH MID MORNING. UPDATED TEXT PRODUCTS
WILL BE SENT SHORTLY.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 242 AM CST WED JAN 13 2016
MAIN CONCERNS IN THE SHORT TERM IS PRECIPITATION TYPE...WHICH
COMES IN TWO DISTINCT AREAS...ONE AREA IN NORTHWEST THROUGH NORTH
CENTRAL/TURTLE MOUNTAINS LATER THIS AFTERNOON THROUGH TONIGHT...AND
THE SECOND AREA DEVELOPING AFTER MIDNIGHT INTO MID MORNING THURSDAY
ACROSS SOUTHWEST AND INTO SOUTH CENTRAL NORTH DAKOTA.
MODEL CONSENSUS ON TIMING AND COVERAGE OF PRECIPITATION STILL
SUSPECT...HOWEVER THE IDEA OF TWO PRECIPITATION AREAS WITH THE
POTENTIAL FOR BOTH LIGHT FREEZING RAIN AND SNOW IS WELL AGREED
UPON PER NAM/GFS/SREF BUFKIT SOUNDINGS. HENCE USED A BLEND OF
THESE SOUNDINGS FOR THE AREAS MENTIONED ABOVE TO ADJUST THE
GIVEN SUPERBLEND WEATHER GRIDS.
CURRENT SUITE OF SATELLITE IMAGERY SHOWS A BREAK IN THE OVERCAST
CONDITIONS FOR WESTERN AND MOST OF CENTRAL NORTH DAKOTA EARLY THIS
MORNING. THE EXCEPTION IS THE TURTLE MOUNTAINS AND INTO THE JAMES
RIVER VALLEY WHERE A FAST MOVING SHORTWAVE EXTENDING FROM SOUTHWEST
MANITOBA WAS GENERATING CLOUDS AND PERIODIC WAVES OF LIGHT SNOW
MOSTLY FROM ROLETTE COUNTY EASTWARD. THIS ACTIVITY WILL WANE
AFTER 12Z WEDS AS THE SHORTWAVE SHIFTS FARTHER EAST. HIGH CLOUDS
QUICKLY INCREASING ACROSS CENTRAL/EASTERN MONTANA INDICATIVE OF
THE NEXT SURGE OF WARM AIR ADVECTION. SHOULD SEE SOME SUNSHINE
EARLY TODAY THEN CLOUDING UP FROM NORTHWEST TO SOUTHEAST. A
BAROCLINIC ZONE WAS SITUATED FROM NORTHWEST INTO NORTH CENTRAL
NORTH DAKOTA/TURTLE MOUNTAINS...AND SOUTHEAST INTO THE NORTHERN
JAMES RIVER VALLEY THIS MORNING. EXPECT A DISTINCT HIGH TEMPERATURE
FORECAST TODAY WITH HIGHS IN THE LOWER 40S FAR SOUTHWEST TO MID-
TEENS IN THE TURTLE MOUNTAINS AS THE BAROCLINIC ZONE TIGHTENS UP
THIS AFTERNOON. A SURFACE LOW IN SOUTHEAST ALBERTA TODAY WILL
SHIFT INTO NORTHEAST MONTANA BY 06Z THURSDAY...THEN TO NEAR BEULAH
BY 12Z THURSDAY. FRONTOGENETICAL FORCING PER NAM INCREASES THIS
AFTERNOON ACROSS NORTHWEST NORTH DAKOTA. SUFFICIENT 850-300MB
OMEGA AND INCREASING SURFACE CONVERGENCE WILL LEAD TO A SLIGHT CHC
OF LIGHT FREEZING RAIN FAR NORTHWEST NORTH DAKOTA/CROSBY AREA BY
MID AFTERNOON INTO EARLY EVENING. PRECIPITATION WILL SPREAD EAST
ACROSS NORTH CENTRAL NORTH DAKOTA INTO THE TURTLE MOUNTAINS BEFORE
MIDNIGHT AND CONTINUE INTO EARLY THURSDAY MORNING. SNOWFALL
ACCUMULATIONS TONIGHT THROUGH 12Z THURSDAY WILL BE UP TO ONE INCH
FOR LOCATIONS NORTH AND EAST OF MINOT. THE THREAT OF LIGHT FREEZING
RAIN WILL EXTEND TO NEAR WILLISTON AND NEW TOWN WEDNESDAY EVENING
/00Z-03Z OR 6PM-9PM CST. THEREAFTER...THE LIGHT FREEZING RAIN THREAT
IN THE NORTH WILL END...AS THE MAIN PERCEPTION SHIELD SHIFTS EAST
INTO A MORE FAVORABLE REGIME FOR ALL SNOW. SOUNDINGS SUPPORT
PRECIPITATION AS ALL SNOW BY THE TIME THE PRECIPITATION REACHES
REACHES MINOT AND THE TURTLE MOUNTAINS.
AFTER MIDNIGHT...AS THE SURFACE LOW ENTERS WESTERN NORTH DAKOTA
AND BEGINS TO TRACK SOUTHEAST...THE BAROCLINIC ZONE WILL BEGIN TO
BE PULLED FROM NORTH TO SOUTH. AT THE SAME TIME ANOTHER SHORTWAVE
WILL SLIDE INTO SOUTHWESTERN NORTH DAKOTA FROM EASTERN MONTANA.
THE DICKINSON AND BISMARCK SOUNDINGS SUPPORT A POTENTIAL FOR A
LIGHT FREEZING RAIN MENTION FROM 09Z-15Z THURSDAY/3AM-9AM CST.
AT THIS TIME...NOT EXPECTING WIDESPREAD FREEZING RAIN NOR A HIGH
PROBABILITY/HIGH CONFIDENT FREEZING RAIN EVENT IN EITHER THE
NORTHWEST OR SOUTHWEST/SOUTH CENTRAL PRECIPITATION AREA. THUS
WILL CONTINUE TO MENTION THIS IN THE HAZARDOUS WEATHER OUTLOOK/HWO
AND LET THE DAYSHIFT HAVE ANOTHER LOOK AT THE DATA TO SEE IF THERE
ARE ANY SIGNIFICANT CHANGES FROM WHAT WAS MENTIONED ABOVE.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 242 AM CST WED JAN 13 2016
THE MAIN FORECAST HIGHLIGHT IN THE LONG TERM PERIOD WILL BE
PRECIPITATION CHANCES EARLY IN THE PERIOD...THEN WIND CHILL
HIGHLIGHTS AS WE MOVE THROUGH THE WEEKEND AND EARLY NEXT WEEK.
A SHORTWAVE TROUGH MOVING ONTO THE NORTHWEST U.S. COAST THIS MORNING
WILL MOVE ACROSS THE NORTHERN ROCKIES TODAY INTO TONIGHT AND INDUCE
SURFACE LOW PRESSURE IN THE LEE OF THE NORTHERN AND CANADIAN
ROCKIES. THE SURFACE LOW IS PROGGED TO BE OVER WESTERN NORTH DAKOTA
BY 12 UTC THURSDAY. THE LOW IS FORECAST TO TRACK SOUTHEAST INTO
SOUTHERN MINNESOTA BY 00 UTC FRIDAY. MODELS ARE IN PRETTY GOOD
AGREEMENT IN SHOWING SOME INTENSIFICATION OF THE MID-LEVEL WAVE AS
IT TRACKS ACROSS NORTH DAKOTA DURING THE DAY THURSDAY. IN
ADDITION...COLDER AIR WILL BEGIN TO DROP SOUTH FROM CANADA. THE
INTERACTION OF THE COLD AIR AND STRENGTHENING WAVE WILL HELP TO
INTENSIFY THE BAROCLINIC ZONE WHICH WILL LIE ACROSS NORTHERN NORTH
DAKOTA THURSDAY MORNING. THIS IS EXPECTED TO BRING A SWATH OF 1
TO 3 INCHES OF SNOW ACROSS THE NORTHWEST AND NORTH CENTRAL AND
INTO THE NORTHERN JAMES RIVER VALLEY FROM LATE WEDNESDAY NIGHT
THROUGH THE DAY ON THURSDAY. ALWAYS CONCERNED WITH A STRENGTHENING
WAVE ALONG A TIGHT BAROCLINIC ZONE AND THE POSSIBILITY OF SOME
FRONTOGENETICALLY INDUCED BANDS OF HIGHER SNOW AMOUNTS. WILL HAVE
TO MONITOR FOR THIS POSSIBILITY AS THE MESOSCALE MODELS REACH INTO
THIS TIMEFRAME. THE 06 UTC NAM IS ALSO A BIT INTERESTING SHOWING
SOME MESOSCALE BANDING WITH HIGHER QPF AMOUNTS. FOR NOW WILL
STICK WITH A MENTION OF 1-3 INCHES OF SNOW FROM WEDNESDAY NIGHT
THROUGH THURSDAY GENERALLY ALONG AND NORTH OF A LINE FROM
WILLISTON TO MINOT AND TO RUGBY...HARVEY AND CARRINGTON. AND MAY
MENTION SOME POSSIBLY LOCAL HIGHER AMOUNTS. ANYWHERE SOUTH OF
THIS LINE COULD SEE UP TO AN INCH OF SNOW DURING THE DAY THURSDAY
AS THE BAROCLINIC ZONE DROPS SOUTH THROUGH SOUTHWEST AND SOUTH
CENTRAL NORTH DAKOTA. FOR THE MOST PART PRECIPITATION REMAINS
ALONG AND NORTH OF THE BAROCLINIC ZONE...BUT THERE IS SOME
INDICATION...MAINLY WITH THE NAM...OF SOME LIGHT PRECIPITATION
PUSHING INTO SOUTHWEST AND SOUTH CENTRAL NORTH DAKOTA FROM LATE
WEDNESDAY NIGHT INTO THURSDAY MORNING. NAM AND GFS BUFKIT SOUNDING
SHOW THAT IF ANY PRECIPITATION THURSDAY MORNING WOULD FALL OVER
THE SOUTHWEST AND SOUTH CENTRAL...THERE WOULD BE A POTENTIAL FOR
SOME LIGHT FREEZING RAIN. THIS POTENTIAL WOULD END BY MID MORNING
ACROSS MOST OF THE SOUTHWEST AND SOUTH CENTRAL...WITH THE
EXCEPTION OF THE FAR SOUTHERN TIER COUNTIES...WHERE WARMER
TEMPERATURES AT THE SURFACE AND ALOFT MAY RESULT IN A RAIN SNOW
MIX INTO THE EARLY AFTERNOON. AT THIS TIME...WE WILL KEEP A
MENTION OF MIXED PRECIPITATION SOUTHWEST AND SOUTH CENTRAL...BUT
THE MODEL QPF AMOUNTS HERE ARE QUITE LIGHT...BUT WILL CERTAINLY
NEED TO MONITOR.
LIGHT SNOW IS THEN EXPECTED TO TAPER OFF THURSDAY EVENING AS COLD
ARCTIC AIR CONTINUES TO FILTER INTO THE STATE. ANOTHER WEAK WAVE
TRACKS ALONG THE BAROCLINIC ZONE ON FRIDAY...WHICH BY THIS TIME IS
OVER WESTERN TO SOUTH CENTRAL NORTH DAKOTA. FOR NOW OUR MULTI-MODEL
BLEND IS GIVING A SPATTERING OF SLIGHT CHANCE POPS ACROSS THE CWA
WHICH SEEMS REASONABLE. IF ANYTHING WE MAY NEED TO BUMP UP POPS
ACROSS THE SOUTHWEST BUT ENOUGH TIME TO SEE HOW LATER RUNS MANIFEST
THIS.
MAIN FOCUS FRIDAY NIGHT AND THROUGH THE WEEKEND WILL BE WIND CHILL
HIGHLIGHTS...MAINLY ALONG...NORTH AND EAST OF LAKE SAKAKAWEA AND THE
MISSOURI RIVER FRIDAY NIGHT-SATURDAY MORNING...THEN ACROSS THE CWA
SATURDAY NIGHT-SUNDAY MORNING. DEPENDING ON RESULTING TEMPERATURES
WE MAY NEED A WIND CHILL WARNING ACROSS THE NORTHEASTERN PORTION OF
THE CWA DURING THIS PERIOD. COLD AIR BEGINS TO ABATE BY EARLY NEXT
WEEK BUT WILL LIKELY SEE A LARGE RANGE OF TEMPERATURES BETWEEN THE
WARMER SOUTHWEST AND COLD NORTHEAST PORTION OF THE CWA.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 621 AM CST WED JAN 13 2016
VFR CIGS/VSBYS EXPECTED AT ALL TERMINALS THROUGH 00Z THURSDAY.
THEREAFTER...CIGS WILL BEGIN TO DETERIORATE TO MVFR/IFR FROM NORTH
TO SOUTH. MVFR CIGS EXPECTED AT KMOT BY 01Z THURSDAY WITH LIGHT SNOW
DEVELOPING BY 05Z REDUCING VSBYS TO MVFR/IFR. THE REST OF THE
TERMINALS WILL TAKE A DOWNWARD TREND TO MVFR/IFR BETWEEN 09Z-12Z
THURSDAY. LIGHT FREEZING RAIN POSSIBLE AT KDIK/KBIS BETWEEN 09Z-15Z
THURSDAY BUT LOW CONFIDENCE THIS FAR OUT TO MENTION AS A PREDOMINATE
FORECAST ELEMENT.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...CJS
SHORT TERM...KS
LONG TERM...TWH
AVIATION...KS
AREA FORECAST DISCUSSION
NWS SAN DIEGO CA
202 PM PST WED JAN 13 2016
.SYNOPSIS...
FAIR WEATHER THROUGH THIS EVENING WITH A FEW PASSING HIGH CLOUDS AND
TEMPERATURES SLIGHTLY BELOW NORMAL FOR THIS TIME OF YEAR. A WEAK
WEATHER SYSTEM WILL BRING INCREASING LOW CLOUDS WEST OF THE
MOUNTAINS TONIGHT WITH A SLIGHT CHANCE OF SPRINKLES. AS HIGH
PRESSURE RIDGE BUILDS OVER SOUTHERN CALIFORNIA...MILD AND DRY
WEATHER WILL LIKELY PREVAIL FROM THURSDAY THROUGH MONDAY OF NEXT
WEEK. A WEATHER DISTURBANCE WILL BRING A SLIGHT CHANCE OF COASTAL
AND VALLEY RAIN SHOWERS AND MOUNTAIN SNOW ON TUESDAY.
&&
.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...
AT 1 PM PST...ON VISIBLE SATELLITE IMAGERY...SCATTERED HIGH CIRRUS
CLOUDS ABOVE 20000 FEET COULD BE OBSERVED STREAMING ACROSS SOUTHERN
CALIFORNIA WITH SCATTERED TO BROKEN LOW CLOUDS CLOUDS PUSHING INTO
OUR OUTER WATERS ZONE. THE METAR AT SAN CLIMENTE REPORTED A CEILING
OF 1100 FEET MSL. SURFACE PRESSURE GRADIENTS CONTINUE TO STRENGTHEN
WITH SAN-IPL GRADIENT NOW AT +2.2 MB.
MILD WEATHER WILL PREVAIL THIS EVENING WITH TEMPERATURES REGION WIDE
NEAR OR SLIGHTLY BELOW NORMAL. AFTER SUN DOWN...SURFACE PRESSURE
GRADIENTS WILL TREND STRONGER ONSHORE AND SCATTERED LOW CLOUDS WILL
PUSH INTO THE COASTAL AND VALLEY REGIONS. BY TONIGHT...MODELS PROG A
WEAK COLD FRONT TO SLIDE SOUTH AND EASTWARD TOWARDS SOUTHERN
CALIFORNIA. THIS FRONT WILL AID IN DEEPENING THE MARINE LAYER AND
BRINING A SLIGHT CHANCE OF SPRINKLES TO THE AREA. WITH THE LOCAL
WRF...NAM4...AND HRRR ARE ALL BACKING OFF ON THE PRECIP...WE WILL BE
LUCKY TO PICK UP MORE THAN 0.02 INCHES OF RAIN AT ANY GIVEN LOCATION.
HOWEVER...THIS PASSING FEATURE WILL STILL WARRANT A SLIGHT CHANCE OF
SPRINKLES WEST OF THE MOUNTAINS FROM THIS EVENING TO EARLY THURSDAY
MORNING.
FROM THURSDAY THROUGH SATURDAY...WEAK RIDGING WILL MOVE OVER THE
DESERT SOUTHWEST...CONTINUING THE NEAR AVERAGE TEMPERATURES AND A
FEW PASSING MID AND HIGH LEVEL CLOUDS. ONSHORE FLOW WILL BRIEFLY
STRENGTHEN ON FRIDAY GENERATING GUSTY WEST WINDS ON THE MOUNTAIN
RIDGETOPS AND DESERT SLOPES.
SUNDAY THROUGH MID NEXT WEEK...LONG RANGE MODELS SHOW A LOW
PRESSURE SYSTEM MOVING THROUGH NORTHERN CALIFORNIA AND THE
PACIFIC NORTHWEST. SOUTHERN CALIFORNIA WILL BE ON THE SOUTHERN
FRINGES OF THIS SYSTEM...LEAVING SO CAL WITH MILD
WEATHER...INCREASED ONSHORE FLOW....AND INTERMITTENT CLOUDINESS.
THE 12Z GFS AND 12Z ECMWF BOTH PLACE LIGHT TO MODERATE PRECIP OVER
PORTIONS OF SOUTHWEST CALIFORNIA ON TUESDAY. HAVE ADDED A SLIGHT
CHANCE OF PRECIPITATION OVER AND WEST OF THE MOUNTAINS FROM
TUESDAY MORNING THROUGH EARLY TUESDAY NIGHT. ANOTHER RIDGE WILL
BUILD IN BEHIND THIS QUICK MOVING TROUGH.
&&
.AVIATION...
132100Z...SCT-BKN CLOUDS AOA 10000 FT MSL THROUGH THIS AFTERNOON.
LOWER CLOUDS AROUND 2000-3000 FEET MSL WILL DEVELOP OVER THE COASTAL
BASIN THIS EVENING AFTER 01Z. COVERAGE COULD BE PATCHY
THOUGH...GIVEN THE EXISTING HIGH CLOUDS. A FEW SPRINKLES ARE
POSSIBLE WEST OF THE MOUNTAINS BETWEEN AROUND 14/04-12Z. PARTLY
CLOUDY WITH HIGH CLOUDS THROUGH THURSDAY AFTERNOON.
&&
.MARINE...
100 PM...NO HAZARDOUS MARINE WEATHER IS EXPECTED THROUGH SATURDAY.
RAPIDLY BUILDING WEST NORTHWEST SWELL ON SUNDAY MAY CREATE HAZARDOUS
SEAS IN THE OUTER WATERS.
&&
.SKYWARN...
SKYWARN ACTIVATION IS NOT REQUESTED. HOWEVER WEATHER SPOTTERS ARE
ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS.
&&
.SGX WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...NONE.
&&
$$
PUBLIC...JT
AVIATION/MARINE...TS
SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NWS LOS ANGELES/OXNARD CA
130 PM PST WED JAN 13 2016
.SYNOPSIS...
COOLER THAN NORMAL TEMPERATURES TO CONTINUE THROUGH THE WEEKEND AS
A SERIES OF WEAK WEATHER SYSTEMS MOVES THROUGH. RAIN CHANCES WILL
BE CONFINED MOSTLY TO SANTA BARBARA AND NORTH. A BETTER CHANCE FOR
RAIN IN ALL AREAS NEXT TUESDAY.
&&
.SHORT TERM (TODAY-SAT)...OUR WEAK FRONT FOR TODAY WASHED OUT EVEN
FASTER THAN EXPECTED AND IS STRUGGLING TO EVEN GENERATE CLOUDS
ACROSS THE SRN PORTION OF THE FORECAST AREA THIS AFTERNOON. HAVE
REMOVED POPS FROM THE FORECAST AND DECREASED CLOUDS QUITE A BIT
OVERNIGHT. THE ONLY EXCEPTION TO THAT IS THE INTERIOR PORTION OF
SLO COUNTY WHICH WILL LIKELY SEE LOW LVL MOISTURE ADVECTING IN
FROM THE SAN JOAQUIN VALLEY LATER TONIGHT CREATING AREAS OF LOW
CLOUDS AND FOG. OTHERWISE JUST PARTLY CLOUDY SKIES.
POST-FRONTAL NORTHWEST WINDS WILL DEVELOP THIS EVENING BUT TODAY`S
MODELS CONTINUED THE DECREASING TREND FROM EARLIER RUNS AND HAVE
OPTED TO KEEP WINDS BELOW ADVISORY LEVELS. STRONGEST WINDS WILL BE
UP IN THE GRAPEVINE, ANTELOPE VALLEY, AND SRN SBA COUNTY.
QUIET WEATHER THU WITH JUST SOME PASSING HIGH CLOUDS. HIGHS ABOUT 5
DEGREES COOLER THAN NORMAL.
ANOTHER WEAK FRONTAL BOUNDARY WILL INCREASE CLOUDS AND RAIN
CHANCES NORTH OF PT CONCEPTION THURSDAY NIGHT INTO FRIDAY MORNING,
THOUGH THE ECMWF IS EVEN WEAKER THAN THE GFS AND BOTH KEEP MOST OF
THE ENERGY WELL TO THE NORTH. SO AT BEST JUST SOME LIGHT PRECIP
NORTHERN AREAS AND SOME CLOUDS IN THE SOUTH.
A RIDGE WILL POP UP ALONG THE WEST COAST FRIDAY AFTERNOON THROUGH
EARLY SATURDAY WHILE A COLD FRONT APPROACHES FROM THE WEST. ALL
THE MODELS SHOW SOME LOW LVL MOISTURE MOVING INTO THE CENTRAL
COAST SATURDAY MORNING WELL AHEAD OF THE COLD FRONT, THOUGH ONLY
THE GFS SPITS OUT ANY PRECIP ALONG THE CENTRAL COAST AS LIFT IS
MINIMAL UNDER THE RIDGE AXIS. WORTHY OF A CHANCE OF RAIN NORTHERN
AREAS BUT NOT MUCH MORE THAN THAT.
THE RIDGE WILL SHIFT EAST SATURDAY BUT NOT BEFORE TAKING A SIZABLE
BITE OUT OF THE APPROACHING COLD FRONT AND THE MODELS PRETTY MUCH
ALL AGREE THERE WON`T BE ENOUGH LEFT TO GENERATE ANYTHING
MEASURABLE SATURDAY NIGHT, BUT MAYBE A FEW SPRINKLES UP NORTH.
.LONG TERM (SUN-WED)...THE RIDGE RETURNS SUNDAY BUT IT WILL BE
ACCOMPANIED BY A FAIR AMOUNT OF HIGH CLOUDS SO PARTLY CLOUDY MOST
AREAS. ON MONDAY A WEAKENING FRONTAL BOUNDARY WILL AGAIN WASH OUT
OVER THE CENTRAL COAST BUT IT MAY HOLD TOGETHER JUST LONG ENOUGH
TO BRING A FEW SPRINKLES OR LIGHT SHOWERS NORTH OF PT CONCEPTION.
PARTLY CLOUDY AND DRY IN THE SOUTH.
MONDAY NIGHT AND TUESDAY A SLIGHTLY DEEPER TROF WILL MOVE THROUGH
NRN CALIFORNIA AND STANDS A BETTER CHANCE OF BRING AT LEAST SOME
LIGHT RAIN TO THE AREA, THOUGH HERE AGAIN THERE ARE SIGNIFICANT
MODEL DIFFERENCES. THE GFS IS PRETTY WET, THOUGH WHY IS VERY
UNCLEAR AS ALMOST ALL THE DYNAMICS ARE NORTH OF THE BAY AREA AND
THERE IS NO PARTICULARLY GOOD REASON WHY THE FRONT SHOULD GENERATE
SUCH PROLIFIC OROGRAPHIC ENHANCEMENT. VASTLY PREFER THE MORE
REASONABLE ECMWF SOLUTION DURING THIS TIME PERIOD WHICH STILL
BRINGS AT LEAST LIGHT RAIN INTO LA COUNTY TUESDAY BUT ABOUT 90%
LESS PRECIP THAN THE GFS.
ALL MODELS SHOW A SHARP RIDGE RETURNING TUESDAY NIGHT INTO
WEDNESDAY FOR DRY WEATHER BUT STILL BELOW NORMAL TEMPS.
&&
.AVIATION...13/1800Z
MID/UPPER LEVEL TROUGH OF LOW PRESSURE OVER THE AREA WILL SHIFT
EAST AND A RIDGE OF HIGH PRESSURE WILL BUILD OVER THE AREA. UPPER LEVEL
MODERATE WEST WINDS WILL BECOME MODERATE NORTHWEST 14/06Z WHILE MID LEVEL
LIGHT TO MODERATE NORTHWEST WINDS PREVAIL OVER THE AREA.
A COLD FRONT WILL DISSIPATE OVER THE SLO/SB COUNTIES THROUGH 13/20Z.
FREEZING LEVEL THIS MORNING WAS 10KFT AND LITTLE CHANGE IS EXPECTED
THURSDAY.
MARINE LAYER AT LAX AT 1700Z IS NONE.
KLAX...CHANCE CIGS 050 AND CIGS 015 AT TIMES BETWEEN 14/00-14/04Z.
CHANCE CIGS 020 BETWEEN 14/11-14/18Z.
KBUR...CHANCE CIGS 028 AT TIMES BETWEEN 14/11-14/15Z.
VIRTUALLY CERTAIN - 95-100%
VERY LIKELY - 80-95%
LIKELY - 60-80%
CHANCE - 30-60%
VERY UNLIKELY - 20% OR LESS
&&
.MARINE...13/200 PM.
NORTHWEST WINDS WILL LIKELY DEVELOP AND INCREASE THIS EVENING AND
SMALL CRAFT ADVISORY CONDITIONS ARE EXPECTED FROM POINT SAL TO
SOUTH OF SAN NICOLAS ISLAND TONIGHT THROUGH THURSDAY MORNING.
OTHERWISE SMALL CRAFT ADVISORY CONDITIONS FOR HAZARDOUS SEAS WILL
CONTINUE FROM PIEDRAS BLANCAS TO SAN CLEMENTE ISLAND THROUGH
TONIGHT. THE SEAS ARE EXPECTED TO SUBSIDE BELOW 10 FEET BRIEFLY
THURSDAY NIGHT AND THEN REBUILD FRIDAY. A 947 MB LOW WITH A GALE
AND STORM FORCE WIND FETCH ORIENTED BETWEEN 280-290 DEGREES
RELATIVE TO VENTURA COUNTY WILL DEVELOP NORTH OF THE HAWAIIAN
ISLANDS TONIGHT THROUGH THURSDAY. THE SEAS ARE EXPECTED TO BUILD
TO 45 FEET SLIGHTLY LARGER THAN THE SEAS THAT WERE GENERATED LAST
WEEK SATURDAY AND THAT PEAKED NEAR SHORE TUESDAY. THE SWELLS WILL
BUILD SATURDAY NIGHT AND SMALL CRAFT ADVISORY FOR HAZARDOUS SEA
CONDITIONS ARE EXPECTED FROM PIEDRAS BLANCAS TO SAN CLEMENTE
ISLAND SUNDAY THROUGH NEXT WEEK MONDAY.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY (SEE LAXMWWLOX).
HIGH SURF ADVISORY (SEE LAXCFWLOX).
&&
$$
PUBLIC...MW
AVIATION/MARINE...30
WWW.WEATHER.GOV/LOSANGELES
[top]
Area Forecast Discussion
National Weather Service Sacramento CA
1040 AM PST WED JAN 13 2016
.SYNOPSIS...
Showers and thunderstorms today, some severe thunderstorms possible
with potential for isolated weak tornadoes, hail, and brief heavy
rain. Accumulating snow in the mountains will impact travel today.
Wet pattern continues for NorCal, potentially very wet early next
week.
&&
.DISCUSSION...
An upper level trough with a surface front is moving through
the area today. This is bringing snow showers to the mountains,
with 2-4 inches of snow so far measured over 6000 feet. Snow
levels are around 5500 feet and falling, reaching below 5000 feet
later today. Chain restrictions are in effect for mountain roads
such as I80 and Highway 50. A Winter Weather Advisory continues
through midnight tonight.
Main issue for today is the potential for strong thunderstorms
this afternoon in the wake of the frontal passage. Scattered
showers have been developing over the area this morning, and
instability has been enough for a few isolated thunderstorms
already. A couple of these passed through the Sacramento metro
area dropping small hail and a brief period of heavy rain. Radar
shows a line of storms moving onshore by Eureka, and this line is
shifting eastward.
Strong storms are possible this afternoon overthe forecast area
with significant low level shear for rotating storms and possible
even weak tornadoes. If there are sufficient breaks in the clouds,
solar heating will give an additional boost to instability. The
best chance for severe weather currently appears to be around
Butte, eastern Tehama and Glenn, and western Yuba counties. Cloud
cover over Shasta County may inhibit severe storm development,
though the HRRR model suggests lines of convection with heavy rain
developing. Burn areas in the Sierra and Lake County could see
brief periods of heavy rain, but quick storm motion should limit
the potential for debris slides.
Gusty winds continue this morning, but mainly peaked overnight and
the early morning hours. Have allowed the Wind Advisory to expire
as winds are expected to continue to decrease through the day. EK
&&
.EXTENDED DISCUSSION (Sunday THROUGH Wednesday)
Sunday is expected to be a transitional period between systems
with relatively flat upper level ridging briefly builds, but some
precipitation chances remain northward of I-80. The next wet system
comes into NorCal Sunday night into Tuesday. Models diverge on the
pattern Wednesday next week with more ridging introduced. We
tailored back precipitation chances and coverage to mainly the
mountains, especially the northern mountains. JClapp
&&
.AVIATION...
Expect scattered showers to continue into the early evening. Isolated
thunderstorms will be possible this afternoon central to north
Sac Valley. Local areas of MVFR conditions could accompany
storms. South winds 10 to 20 kt local gusts to 30 kt will be
possible across the Valley north of Sacramento.
&&
.STO Watches/Warnings/Advisories...
Winter Weather Advisory until midnight PST tonight for West
Slope Northern Sierra Nevada-Western Plumas County/Lassen Park.
&&
$$
AREA FORECAST DISCUSSION
NWS SAN DIEGO CA
931 AM PST WED JAN 13 2016
.SYNOPSIS...
FAIR SKIES TODAY WITH A FEW PASSING HIGH CLOUDS AND TEMPERATURES
SLIGHTLY BELOW NORMAL FOR THIS TIME OF YEAR. A WEAK WEATHER SYSTEM
WILL BRING INCREASING LOW CLOUDS WEST OF THE MOUNTAINS TONIGHT WITH
A SLIGHT CHANCE OF SPRINKLES. AS A WEAK HIGH PRESSURE RIDGE BUILDS
OVER THE WEST...MILD AND DRY WEATHER WILL LIKELY PREVAIL FROM
THURSDAY THROUGH MID NEXT WEEK.
&&
.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...
AT 9 AM PST...THE 12Z KNKX SOUNDING SHOWED DRY AIR FROM THE SURFACE
UP THROUGH AROUND 25000 FEET MSL...AND NORTHWEST WINDS AT ALL
LEVELS. IR SATELLITE INDICATED A WELL DEFINED STORM SYSTEM CENTERED
OFF OF THE OREGON COAST WITH A COLD FRONT EXTENDING SOUTHWARD
TOWARDS POINT CONCEPTION. THIS FEATURE WILL BE THE MAIN THE FOCUS
OVER THE NEXT 24 HOURS.
MILD WEATHER WILL CONTINUE THROUGH THIS EVENING WITH TEMPERATURES
REGION WIDE NEAR OR SLIGHTLY BELOW NORMAL. BY TONIGHT...MODELS PROG
THE AFOREMENTIONED COLD FRONT TO WEAKEN CONSIDERABLY AND SLIDE SOUTH
AND EASTWARD TOWARDS SOUTHERN CALIFORNIA. AFTER SUN DOWN SURFACE
PRESSURE GRADIENTS WILL TREND STRONGER ONSHORE AND SCATTERED LOW
CLOUDS WILL PUSH INTO THE COASTAL REGIONS. WITH THE LOCAL
WRF...NAM4...AND HRRR ARE ALL BACKING OFF ON THE PRECIP...WE WILL BE
LUCKY TO PICK UP MORE THAN 0.02 INCHES OF RAIN AT ANY GIVEN LOCATION.
HOWEVER...THIS PASSING FEATURE WILL STILL WARRANT A SLIGHT CHANCE OF
SPRINKLES WEST OF THE MOUNTAINS FROM THIS EVENING TO EARLY THURSDAY
MORNING.
FROM THURSDAY THROUGH THE WEEKEND...WEAK RIDGING WILL MOVE OVER THE
DESERT SOUTHWEST...CONTINUING THE NEAR AVERAGE TEMPERATURES AND A
FEW PASSING MID AND HIGH LEVEL CLOUDS. ONSHORE FLOW WILL BRIEFLY
STRENGTHEN ON FRIDAY GENERATING GUSTY WEST WINDS ON THE MOUNTAIN
RIDGETOPS AND DESERT SLOPES.
EARLY/MID NEXT WEEK...ANOTHER ROUND OF WEAK RIDGES AND TROUGHS WILL
PASS OVER CALIFORNIA. BOTH THE 12Z GFS AND 00Z ECMWF SHOW A RATHER
STRONG AND STAGNANT LONG WAVE TROUGH CENTERED OVER THE GULF OF
ALASKA. HOWEVER...THE MAIN ENERGY FROM THE DISTURBANCES ROUNDING THE
TROUGH WILL PUSH INTO NORTHERN CALIFORNIA...LEAVING SOUTHERN
CALIFORNIA WITH MILD WEATHER...INCREASED ONSHORE FLOW....AND
INTERMITTENT CLOUDINESS. MODELS GENERATE SMALL AMOUNTS OF PRECIP
OVER AND WEST OF OUR LOCAL MOUNTAINS ON TUESDAY...FROM THE TAIL END
OF A COLD FRONT...BUT WILL CONTINUE MONITOR FOR BETTER MODEL RUN TO
RUN CONSISTENCY.
&&
.AVIATION...
131800Z...INCREASING CLOUDS AOA 8000 FEET MSL DURING THE DAY.
LOWER CLOUDS AT 2000-3000 FEET MSL WILL FILL THE COASTAL BASIN
THIS EVENING AFTER 01Z WITH ISOLATED -SHRA AFTER 04Z.
&&
.MARINE...
800 AM...NO HAZARDOUS MARINE WEATHER IS EXPECTED THROUGH
SATURDAY. RAPIDLY BUILDING WEST NORTHWEST SWELL ON SUNDAY MAY
CREATE HAZARDOUS SEAS IN THE OUTER WATERS.
&&
.SKYWARN...
SKYWARN ACTIVATION IS NOT REQUESTED. HOWEVER WEATHER SPOTTERS ARE
ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS.
&&
.SGX WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...NONE.
&&
$$
PUBLIC...JT
AVIATION/MARINE...TS
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1140 AM CST WED JAN 13 2016
.UPDATE...
1015 AM CST
THE GOING FORECAST AND MESSAGE FOR TODAY REMAIN IN GOOD SHAPE
WITH A PERIOD OF LIGHT SNOW FOR A GOOD PORTION OF THE FORECAST
AREA THROUGH MAINLY 3-4 PM. HAVE ONLY MADE SUBTLE ADJUSTMENTS TO
SPECIFIC HOURLY TIMING. FOR IMPACTS...THIS CONTINUES TO LOOK LIKE
MOST OF THE SNOW OUTSIDE OF SOME SPOTTY SNOW SHOWERS TO BE MAINLY
DONE BY 4 PM AND THUS SANDWICHED BETWEEN THE PRIMARY COMMUTES FOR
MANY. OBVIOUSLY LINGERING IMPACTS OF LIGHTLY SNOW COVERED ROADS
MAY RESULT.
LIGHT SNOW WITH 6-9SM VISIBILITY IS BEING OBSERVED ACROSS MOST OF
THE NORTHERN ILLINOIS CWA AS OF 1000 AM WITHIN BROAD WARM
ADVECTION...WITH EVEN LOCAL VISIBILITY AROUND 3SM OUT OUR WINDOW
HERE IN ROMEOVILLE. THE WARM ADVECTION FLOW HAS GRADUALLY BEEN
STRENGTHENING PER THE DVN AND LOT VAD WIND PROFILERS AND THUS THE
ISENTROPIC ASCENT HAS AS WELL. THIS SHOULD FURTHER INCREASE AS THE
PRIMARY SHORT WAVE DISTURBANCE LOCATED OVER SOUTHERN MN PROGRESSES
QUICKLY TOWARD THE AREA. THE RAP ISENTROPIC ANALYSIS CAPTURES WHAT
IS OCCURRING WELL WITH A COMPACT AREA OF ASCENT LINING UP WELL
WITH RADAR...AND ITS THERMAL PROFILES ARE ALSO PRETTY CLOSE TO
RECENT AMDAR DATA. SO CONFIDENCE IN THE RAP AND HRRR SOLUTIONS
REMAIN FAIRLY HIGH AND THUS ONLY MINOR MASSAGING TO THE CURRENT
FORECAST WITH THIS DATA.
THE THERMAL PROFILE ON RECENT AMDAR DATA FROM NEAR MDW INDICATES
THE LOWEST 10,000 FT OF THE SOUNDING LOCATED BETWEEN -10C AND
-15C...CLASSIC OF A COLD AIR MASS. WITH ROOM FOR A LITTLE BIT OF
WET BULB COOLING TO OFFSET THE WARM ADVECTION...THE THERMAL
PROFILE SHOULD LIKELY REMAIN AS SUCH THROUGH THE NEXT SEVERAL HOUR
SNOWFALL...AND THUS ASSIST IN SOME LARGE SNOWFLAKE SIZE AT LEAST
IN THE CLOUD LAYER. SO STILL THINKING A COUPLE TENTHS TO ONE HALF
INCH WITH LOCALIZED ONE INCH AMOUNTS OF FLUFFY SNOW POSSIBLE.
MTF
&&
.SHORT TERM...
353 AM CST
TODAY AND TONIGHT...
FOCUS FOR TODAY IS ON ANOTHER LIGHT(ER) SNOW EVENT DEVELOPING
FROM MID-MORNING THROUGH THIS AFTERNOON.
REGIONAL RADAR MOSAIC DEPICTING SOME WEAK RETURNS ACROSS PORTIONS
OF CENTRAL IOWA AT 09Z...ASSOCIATED WITH ISENTROPIC WARM ADVECTION
ASCENT WITH A MINOR AMPLITUDE SHORT WAVE TROUGH PROPAGATING
SOUTHEAST ACROSS EASTERN NEBRASKA/WESTERN IOWA PER GOES WATER
VAPOR IMAGERY. SUITE OF GUIDANCE INDICATE THIS AREA OF LIGHT SNOW
WILL EXPAND EASTWARD INTO SOUTHERN WI/NORTHERN IL AND NORTHWEST
INDIANA THROUGH MID-DAY...AS ANOTHER FASTER MOVING DISTURBANCE
RIPPLES QUICKLY FROM THE CANADIAN PRAIRIES/NORTHERN PLAINS TO THE
FORECAST AREA THIS AFTERNOON. LATEST WRF-NAM/RAP GUIDANCE
INDICATES MODEST LIFT INTERSECTING ABOUT A 75 MB DEEP DENDRITIC
GROWTH ZONE BETWEEN ROUGHLY 600-700 MB...THOUGH HIGHER RELATIVE
HUMIDITY IS LOCATED BENEATH THIS ZONE AND FORCING IS
WEAKER/SHORTER LIVED THAN WITH THE MUCH STRONGER SYSTEM OF THIS
PAST MONDAY. VARIOUS MODEL QPF/S ARE ONLY A COUPLE OF HUNDREDTHS
OF AN INCH...WITH EXPECTED SNOW/LIQUID RATIOS PERHAPS 16-19:1
YIELDING GENERALLY AN INCH OR LESS. SURFACE TEMPS WILL RISE INTO
THE TEENS/LOW 20S THROUGH THIS AFTERNOON SO SNOW SHOULD HAVE NO
TROUBLE STICKING. THE SECOND QUICK-MOVING MID-LEVEL SHORT WAVE IS
PROGGED TO MOVE EAST OF THE CWA BY THIS EVENING...BRINGING
PRECIPITATION TO AN END. WITH WEAK SURFACE REFLECTION/WARM FRONT
MOVING TO THE EAST-NORTHEAST OF THE AREA TONIGHT...TEMPERATURES
LOOK TO REMAIN NEARLY STEADY FROM LATE DAY HIGHS. READINGS IN THE
20S/HIGH TEENS OVERNIGHT SHOULD BE A WELCOME RESPITE FROM THE
SINGLE DIGITS AND LOCAL SUB-ZERO NUMBERS OF EARLY THIS MORNING.
RATZER
&&
.LONG TERM...
353 AM CST
THURSDAY THROUGH TUESDAY...
MILDER WEATHER...A BRIEF JANUARY THAW...WILL START THE EXTENDED
PERIOD THURSDAY INTO FRIDAY AS UPPER FLOW FLATTENS AHEAD OF AN
UPPER TROUGH WHICH IS CURRENTLY APPROACHING THE PACIFIC COAST.
MODELS HAVE TRENDED FARTHER SOUTH WITH SOUTHERN STREAM ENERGY NOW
TRACKING INTO NORTHERN MEXICO...WITH DOMINANT NORTHERN STREAM
SURFACE LOW PROGGED TO MOVE JUST NORTH OF THE CWA THURSDAY NIGHT.
WITH SOUTH WINDS AND AIR TEMPS HOLDING ABOVE
FREEZING...DRIZZLE/LIGHT RAIN EXPECTED TO DEVELOP LATE THURSDAY
NIGHT AND CONTINUE INTO FRIDAY AS MID-LEVEL WAVE AND SURFACE LOW
PASS. SOME CONCERNS EXIST THAT SNOW COVER AND COLD GROUND MAY KEEP
SURFACE TEMPS NEAR FREEZING THURSDAY NIGHT WHICH COULD RESULT IN
PATCHY FREEZING DRIZZLE...AND THE POTENTIAL FOR FOG INCREASES AS
WELL WITH MOIST ADVECTION FROM THE SOUTH AND DEW POINT TEMPS
CLIMBING ABOVE FREEZING THURSDAY NIGHT/FRIDAY MORNING. THE COLUMN
DOES COOL ENOUGH TO CHANGE PRECIPITATION OVER TO SNOW POST-
FRONTALLY FRIDAY AFTERNOON/NIGHT... THOUGH LITTLE ACCUMULATION
EXPECTED WITH ONLY LIGHT QPF DEPICTED IN THE COLDER AIR.
MEDIUM/LONG RANGE SOLUTIONS CONTINUE TO PULL ARCTIC AIR BACK INTO
THE REGION SATURDAY NIGHT INTO EARLY NEXT WEEK...WITH ANOTHER PUSH
OF -20 DEG 850 MB AIR INDICATED BY BOTH ECMWF/GFS SUNDAY/SUNDAY
NIGHT. SINGLE DIGIT TEMPS ARRIVE SATURDAY NIGHT AND
SUNDAY...LIKELY DIPPING BELOW ZERO IN MANY SPOTS BY MONDAY
MORNING. SURFACE HIGH PRESSURE RIDGE MOVES ACROSS THE REGION
MONDAY/MONDAY NIGHT...THEN FLOW FLATTENS WITH ANOTHER MODERATING
TREND APPEARING TUESDAY INTO MID-NEXT WEEK.
RATZER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* SNOW THROUGH MID AFTERNOON REDUCING VSBY TO MVFR AND POSSIBLY
IFR AT TIMES. LIGHT ACCUMULATION LESS THAN AN INCH POSSIBLE.
* POTENTIAL FOR MVFR/IFR CIGS OVERNIGHT.
BMD
//DISCUSSION...UPDATED 18Z...
LIGHT SNOW IS IN PLACE ACROSS NORTHERN ILLINOIS EARLY THIS
AFTERNOON AND IS EXPECTED TO PERSIST FOR A FEW MORE HOURS WITH
CONDITIONS IMPROVING AROUND 21Z. SO FAR VSBY HAS BEEN HIGHER THAN
ANTICIPATED...HOWEVER FORECAST SOUNDINGS SUGGEST THERE COULD BE
SOME ENHANCEMENT OVER THE NEXT FEW HOURS...AND THIS IS BEING SEEN
ACROSS FAR SOUTH/SOUTHEAST WISCONSIN WHERE A FEW SITES ARE
REPORTING 2-3SM. LIGHT ACCUMULATIONS UNDER AND INCH STILL APPEAR
POSSIBLE. UPPER LEVEL WAVE IS PROGGED TO PASS OVERHEAD MID
AFTERNOON WITH DRIER MID LEVEL MOVING IN BEHIND. THIS SHOULD ALLOW
PRECIP TO END.
ATTENTION WILL TURN TO CIGS BEHIND THE WAVE WITH SEVERAL MODELS
SUGGESTING THE POSSIBILITY FOR IFR OR LOW END MVFR CIGS DEVELOPING
LATE THIS EVENING AND OVERNIGHT. IT APPEARS THE TERMINALS WILL
BE NEAR THE EDGE OF THE LOWER STRATUS WHICH WILL BE MORE
WIDESPREAD OVER WISCONSIN...AND GIVEN TYPICAL MOIST BIAS OF THE
NAM/MET CONFIDENCE IS TOO LOW IN THE MEANTIME TO MENTION IN THE
TAF.
BMD
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* MEDIUM-HIGH CONFIDENCE IN SNOW TIMING/DURATION. LOW-MEDIUM ON
VSBY.
* LOW CONFIDENCE IN CIG TRENDS LATE THIS EVENING AND TONIGHT.
BMD
//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...
* THURSDAY NIGHT...CHANCE OF RAIN/DRIZZLE. IFR/LIFR LIKELY. SOUTH
WINDS.
* FRIDAY...RAIN CHANGING TO SNOW. IFR LIKELY. SOUTHWEST WINDS
SHIFTING NORTHWEST.
* SATURDAY AND SUNDAY...DRY. MVFR POSSIBLE. GUSTY NORTHWEST WINDS.
* MONDAY...DRY/VFR. NORTHWEST WINDS.
* TUESDAY...DRY. MVFR POSSIBLE. WESTERLY WINDS.
&&
.MARINE...
312 AM...HIGH PRESSURE OVER THE OHIO VALLEY WILL MOVE SOUTHEAST
TODAY AS LOW PRESSURE DEVELOPS OVER LAKE SUPERIOR. THIS WILL
MAINTAIN A WEST/SOUTHWEST WIND IN THE 15-25KT RANGE THROUGH THIS
EVENING. WINDS WILL SLOWLY DIMINISH TONIGHT WITH LIGHT WINDS
EXPECTED OVER NORTHERN PORTIONS OF THE LAKE THURSDAY. SOUTHERLY
WINDS WILL CONTINUE OVER THE SOUTHERN PART OF THE LAKE AS ANOTHER
LOW MOVES ACROSS THE NORTHERN PLAINS THURSDAY AND ACROSS THE
WESTERN LAKES REGION FRIDAY. DUE TO THE TRACK OF THE LOW ACROSS
THE LAKE...CHANGES TO WIND DIRECTIONS CAN BE EXPECTED WITH LATER
FORECASTS. BUT EASTERLY WINDS OVER THE NORTHERN PART OF THE LAKE
AND SOUTHERLY WINDS OVER THE SOUTHERN PART OF THE LAKE ARE
EXPECTED AS THE LOW APPROACHES. ONCE IT PASSES...WINDS WILL SHIFT
TO THE NORTHWEST WITH A PERIOD OF 30KTS EXPECTED FRIDAY NIGHT WITH
LOW END GALES POSSIBLE. WINDS MAY DIMINISH A BIT SATURDAY BUT AS
MUCH COLDER AIR SPREADS BACK ACROSS THE REGION SATURDAY NIGHT AND
SUNDAY...WINDS WILL LIKELY INCREASE BACK TO 30 KT OR POSSIBLY LOW
END GALES. FREEZING SPRAY WILL ALSO BE POSSIBLE...SATURDAY NIGHT
THROUGH MONDAY. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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AREA FORECAST DISCUSSION...UPDATED
NWS CHICAGO/ROMEOVILLE IL
1016 AM CST WED JAN 13 2016
.UPDATE...
1015 AM CST
THE GOING FORECAST AND MESSAGE FOR TODAY REMAIN IN GOOD SHAPE
WITH A PERIOD OF LIGHT SNOW FOR A GOOD PORTION OF THE FORECAST
AREA THROUGH MAINLY 3-4 PM. HAVE ONLY MADE SUBTLE ADJUSTMENTS TO
SPECIFIC HOURLY TIMING. FOR IMPACTS...THIS CONTINUES TO LOOK LIKE
MOST OF THE SNOW OUTSIDE OF SOME SPOTTY SNOW SHOWERS TO BE MAINLY
DONE BY 4 PM AND THUS SANDWICHED BETWEEN THE PRIMARY COMMUTES FOR
MANY. OBVIOUSLY LINGERING IMPACTS OF LIGHTLY SNOW COVERED ROADS
MAY RESULT.
LIGHT SNOW WITH 6-9SM VISIBILITY IS BEING OBSERVED ACROSS MOST OF
THE NORTHERN ILLINOIS CWA AS OF 1000 AM WITHIN BROAD WARM
ADVECTION...WITH EVEN LOCAL VISIBILITY AROUND 3SM OUT OUR WINDOW
HERE IN ROMEOVILLE. THE WARM ADVECTION FLOW HAS GRADUALLY BEEN
STRENGTHENING PER THE DVN AND LOT VAD WIND PROFILERS AND THUS THE
ISENTROPIC ASCENT HAS AS WELL. THIS SHOULD FURTHER INCREASE AS THE
PRIMARY SHORT WAVE DISTURBANCE LOCATED OVER SOUTHERN MN PROGRESSES
QUICKLY TOWARD THE AREA. THE RAP ISENTROPIC ANALYSIS CAPTURES WHAT
IS OCCURRING WELL WITH A COMPACT AREA OF ASCENT LINING UP WELL
WITH RADAR...AND ITS THERMAL PROFILES ARE ALSO PRETTY CLOSE TO
RECENT AMDAR DATA. SO CONFIDENCE IN THE RAP AND HRRR SOLUTIONS
REMAIN FAIRLY HIGH AND THUS ONLY MINOR MASSAGING TO THE CURRENT
FORECAST WITH THIS DATA.
THE THERMAL PROFILE ON RECENT AMDAR DATA FROM NEAR MDW INDICATES
THE LOWEST 10,000 FT OF THE SOUNDING LOCATED BETWEEN -10C AND
-15C...CLASSIC OF A COLD AIR MASS. WITH ROOM FOR A LITTLE BIT OF
WET BULB COOLING TO OFFSET THE WARM ADVECTION...THE THERMAL
PROFILE SHOULD LIKELY REMAIN AS SUCH THROUGH THE NEXT SEVERAL HOUR
SNOWFALL...AND THUS ASSIST IN SOME LARGE SNOWFLAKE SIZE AT LEAST
IN THE CLOUD LAYER. SO STILL THINKING A COUPLE TENTHS TO ONE HALF
INCH WITH LOCALIZED ONE INCH AMOUNTS OF FLUFFY SNOW POSSIBLE.
MTF
&&
.SHORT TERM...
353 AM CST
TODAY AND TONIGHT...
FOCUS FOR TODAY IS ON ANOTHER LIGHT(ER) SNOW EVENT DEVELOPING
FROM MID-MORNING THROUGH THIS AFTERNOON.
REGIONAL RADAR MOSAIC DEPICTING SOME WEAK RETURNS ACROSS PORTIONS
OF CENTRAL IOWA AT 09Z...ASSOCIATED WITH ISENTROPIC WARM ADVECTION
ASCENT WITH A MINOR AMPLITUDE SHORT WAVE TROUGH PROPAGATING
SOUTHEAST ACROSS EASTERN NEBRASKA/WESTERN IOWA PER GOES WATER
VAPOR IMAGERY. SUITE OF GUIDANCE INDICATE THIS AREA OF LIGHT SNOW
WILL EXPAND EASTWARD INTO SOUTHERN WI/NORTHERN IL AND NORTHWEST
INDIANA THROUGH MID-DAY...AS ANOTHER FASTER MOVING DISTURBANCE
RIPPLES QUICKLY FROM THE CANADIAN PRAIRIES/NORTHERN PLAINS TO THE
FORECAST AREA THIS AFTERNOON. LATEST WRF-NAM/RAP GUIDANCE
INDICATES MODEST LIFT INTERSECTING ABOUT A 75 MB DEEP DENDRITIC
GROWTH ZONE BETWEEN ROUGHLY 600-700 MB...THOUGH HIGHER RELATIVE
HUMIDITY IS LOCATED BENEATH THIS ZONE AND FORCING IS
WEAKER/SHORTER LIVED THAN WITH THE MUCH STRONGER SYSTEM OF THIS
PAST MONDAY. VARIOUS MODEL QPF/S ARE ONLY A COUPLE OF HUNDREDTHS
OF AN INCH...WITH EXPECTED SNOW/LIQUID RATIOS PERHAPS 16-19:1
YIELDING GENERALLY AN INCH OR LESS. SURFACE TEMPS WILL RISE INTO
THE TEENS/LOW 20S THROUGH THIS AFTERNOON SO SNOW SHOULD HAVE NO
TROUBLE STICKING. THE SECOND QUICK-MOVING MID-LEVEL SHORT WAVE IS
PROGGED TO MOVE EAST OF THE CWA BY THIS EVENING...BRINGING
PRECIPITATION TO AN END. WITH WEAK SURFACE REFLECTION/WARM FRONT
MOVING TO THE EAST-NORTHEAST OF THE AREA TONIGHT...TEMPERATURES
LOOK TO REMAIN NEARLY STEADY FROM LATE DAY HIGHS. READINGS IN THE
20S/HIGH TEENS OVERNIGHT SHOULD BE A WELCOME RESPITE FROM THE
SINGLE DIGITS AND LOCAL SUB-ZERO NUMBERS OF EARLY THIS MORNING.
RATZER
&&
.LONG TERM...
353 AM CST
THURSDAY THROUGH TUESDAY...
MILDER WEATHER...A BRIEF JANUARY THAW...WILL START THE EXTENDED
PERIOD THURSDAY INTO FRIDAY AS UPPER FLOW FLATTENS AHEAD OF AN
UPPER TROUGH WHICH IS CURRENTLY APPROACHING THE PACIFIC COAST.
MODELS HAVE TRENDED FARTHER SOUTH WITH SOUTHERN STREAM ENERGY NOW
TRACKING INTO NORTHERN MEXICO...WITH DOMINANT NORTHERN STREAM
SURFACE LOW PROGGED TO MOVE JUST NORTH OF THE CWA THURSDAY NIGHT.
WITH SOUTH WINDS AND AIR TEMPS HOLDING ABOVE
FREEZING...DRIZZLE/LIGHT RAIN EXPECTED TO DEVELOP LATE THURSDAY
NIGHT AND CONTINUE INTO FRIDAY AS MID-LEVEL WAVE AND SURFACE LOW
PASS. SOME CONCERNS EXIST THAT SNOW COVER AND COLD GROUND MAY KEEP
SURFACE TEMPS NEAR FREEZING THURSDAY NIGHT WHICH COULD RESULT IN
PATCHY FREEZING DRIZZLE...AND THE POTENTIAL FOR FOG INCREASES AS
WELL WITH MOIST ADVECTION FROM THE SOUTH AND DEW POINT TEMPS
CLIMBING ABOVE FREEZING THURSDAY NIGHT/FRIDAY MORNING. THE COLUMN
DOES COOL ENOUGH TO CHANGE PRECIPITATION OVER TO SNOW POST-
FRONTALLY FRIDAY AFTERNOON/NIGHT... THOUGH LITTLE ACCUMULATION
EXPECTED WITH ONLY LIGHT QPF DEPICTED IN THE COLDER AIR.
MEDIUM/LONG RANGE SOLUTIONS CONTINUE TO PULL ARCTIC AIR BACK INTO
THE REGION SATURDAY NIGHT INTO EARLY NEXT WEEK...WITH ANOTHER PUSH
OF -20 DEG 850 MB AIR INDICATED BY BOTH ECMWF/GFS SUNDAY/SUNDAY
NIGHT. SINGLE DIGIT TEMPS ARRIVE SATURDAY NIGHT AND
SUNDAY...LIKELY DIPPING BELOW ZERO IN MANY SPOTS BY MONDAY
MORNING. SURFACE HIGH PRESSURE RIDGE MOVES ACROSS THE REGION
MONDAY/MONDAY NIGHT...THEN FLOW FLATTENS WITH ANOTHER MODERATING
TREND APPEARING TUESDAY INTO MID-NEXT WEEK.
RATZER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* LIGHT SNOW CONTINUING THRU MID AFTERNOON...WITH IFR VIS AND
MVFR CIGS.
* POSSIBLE MVFR OR IFR CIGS OVERNIGHT INTO THURSDAY MORNING.
CMS/BMD
//DISCUSSION...UPDATED 12Z...
AN UPPER WAVE WILL MOVE ACROSS THE AREA LATER THIS MORNING INTO
THIS AFTERNOON WITH A BAND OF LIGHT SNOW THAT WILL LIKELY DEVELOP
RIGHT OVER THE TERMINALS. ONLY CHANGE TO PREVIOUS FORECAST WAS TO
DELAY IFR VIS UNTIL 17Z FOR CHICAGO TERMINALS...BUT TWEAKS TO
TIMING CAN BE EXPECTED AS TRENDS EMERGE LATER THIS MORNING. LIGHT
SNOW WILL LIKELY CONTINUE FOR A 3-5 HOUR PERIOD AND THEN TAPER OFF
TO FLURRIES BY MID/LATE AFTERNOON.
SOUTHWEST WINDS UNDER 10KTS THIS MORNING WILL INCREASE INTO THE
10-15KT RANGE AND GUIDANCE IS NOW SHOWING WINDS MAY BE A BIT
STRONGER ALONG WITH SOME GUSTS INTO THE MID/UPPER TEEN RANGE.
WHILE NOT TOO STRONG...THIS COULD CAUSE SOME BLOWING OR LOW
DRIFTING SNOW.
CIGS WILL LIKELY BECOME VFR BY THIS EVENING BUT WARM AIR ADVECTION
BEGINS OVERNIGHT...OVER THE FRESH SNOW PACK AND ITS POSSIBLE THAT
MVFR OR PERHAPS IFR CIGS MAY DEVELOP BY DAYBREAK THURSDAY. GIVEN
THE UNCERTAINTY ONLY HAVE SCATTERED MENTIONED WITH THIS FORECAST.
CMS
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* MEDIUM-HIGH FOR SNOW TIMING/DURATION BUT LOW-MEDIUM FOR
VIS/CIGS.
* HIGH FOR WINDS THRU THE PERIOD.
* LOW FOR CIGS OVERNIGHT INTO THURSDAY MORNING. CMS/BMD
//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...
* THURSDAY NIGHT...CHANCE OF RAIN/DRIZZLE. IFR/LIFR LIKELY. SOUTH
WINDS.
* FRIDAY...RAIN CHANGING TO SNOW. IFR LIKELY. SOUTHWEST WINDS
SHIFTING NORTHWEST.
* SATURDAY AND SUNDAY...DRY. MVFR POSSIBLE. GUSTY NORTHWEST WINDS.
* MONDAY...DRY/VFR. NORTHWEST WINDS.
* TUESDAY...DRY. MVFR POSSIBLE. WESTERLY WINDS.
&&
.MARINE...
312 AM...HIGH PRESSURE OVER THE OHIO VALLEY WILL MOVE SOUTHEAST
TODAY AS LOW PRESSURE DEVELOPS OVER LAKE SUPERIOR. THIS WILL
MAINTAIN A WEST/SOUTHWEST WIND IN THE 15-25KT RANGE THROUGH THIS
EVENING. WINDS WILL SLOWLY DIMINISH TONIGHT WITH LIGHT WINDS
EXPECTED OVER NORTHERN PORTIONS OF THE LAKE THURSDAY. SOUTHERLY
WINDS WILL CONTINUE OVER THE SOUTHERN PART OF THE LAKE AS ANOTHER
LOW MOVES ACROSS THE NORTHERN PLAINS THURSDAY AND ACROSS THE
WESTERN LAKES REGION FRIDAY. DUE TO THE TRACK OF THE LOW ACROSS
THE LAKE...CHANGES TO WIND DIRECTIONS CAN BE EXPECTED WITH LATER
FORECASTS. BUT EASTERLY WINDS OVER THE NORTHERN PART OF THE LAKE
AND SOUTHERLY WINDS OVER THE SOUTHERN PART OF THE LAKE ARE
EXPECTED AS THE LOW APPROACHES. ONCE IT PASSES...WINDS WILL SHIFT
TO THE NORTHWEST WITH A PERIOD OF 30KTS EXPECTED FRIDAY NIGHT WITH
LOW END GALES POSSIBLE. WINDS MAY DIMINISH A BIT SATURDAY BUT AS
MUCH COLDER AIR SPREADS BACK ACROSS THE REGION SATURDAY NIGHT AND
SUNDAY...WINDS WILL LIKELY INCREASE BACK TO 30 KT OR POSSIBLY LOW
END GALES. FREEZING SPRAY WILL ALSO BE POSSIBLE...SATURDAY NIGHT
THROUGH MONDAY. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
542 PM EST WED JAN 13 2016
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 231 PM EST WED JAN 13 2016
A LOW PRESSURE SYSTEM WILL BRING RAIN TO THE AREA THURSDAY NIGHT
INTO FRIDAY...ALONG WITH SOME SNOW CHANCES FRIDAY NIGHT. MUCH COLDER
AIR WILL MOVE IN STARTING SATURDAY...AND SOME LIGHT SNOW IS POSSIBLE
INTO SUNDAY AS THE COLD AIR MOVES IN. SOME LIGHT PRECIPITATION IS
POSSIBLE NEXT WEDNESDAY WITH ANOTHER SYSTEM. THE COLDER AIR WILL
MODERATE SOME MID WEEK NEXT WEEK.
&&
.NEAR TERM.../REST OF THIS AFTERNOON AND TONIGHT/
ISSUED AT 231 PM EST WED JAN 13 2016
AN UPPER WAVE IS GENERATING SOME LIGHT SNOW ACROSS MAINLY THE
NORTHERN THIRD OF THE AREA THIS AFTERNOON...WITH SCATTERED LIGHT
SNOW SHOWERS ACROSS THE REMAINDER OF THE NORTHERN HALF.
THE SNOW WILL MOVE QUICKLY EAST THIS AFTERNOON. HRRR MODEL SHOWING
PERHAPS SOME LINGERING SNOW SHOWERS ACROSS THE FAR NORTHEAST AT
00Z...SO KEPT TOKEN 20 POPS THERE FOR AN HOUR OR TWO. OTHERWISE THE
NIGHT WILL BE DRY WITH A LACK OF FORCING.
HOWEVER...WARM ADVECTION BEGINS...SO TEMPERATURES WILL GRADUALLY
WARM OVERNIGHT. LOW TEMPERATURES WILL THUS LIKELY OCCUR NEAR 00Z.
WITH THE WARM ADVECTION ALOFT EXPECT SOME MID AND HIGH CLOUDS AT
TIMES DURING THE NIGHT. SOME CONCERN ABOUT LOW CLOUDS DEVELOPING
LATER TONIGHT AS DEWPOINTS RISE...BUT AM NOT CONFIDENT ENOUGH TO
INCLUDE AT THIS TIME.
&&
.SHORT TERM.../THURSDAY THROUGH SATURDAY/
ISSUED AT 231 PM EST WED JAN 13 2016
FOCUS IS ON CHANCES FOR PRECIPITATION. OVERALL MODELS ARE CLOSE
ENOUGH THAT A BLEND WAS USED.
WARM ADVECTION CONTINUES ON THURSDAY...BUT NOT ENOUGH FORCING OR
MOISTURE AROUND FOR ANY PRECIPITATION. WENT A LITTLE COOLER THAN MOS
FOR HIGH TEMPERATURES GIVEN THE SNOW COVER AND COLD GROUND.
ISENTROPIC LIFT INCREASES THURSDAY NIGHT AHEAD OF AN APPROACHING
SYSTEM...BUT FORCING/MOISTURE REMAIN RELATIVELY LIMITED. WILL ONLY
GO SLIGHT CHANCE POPS...WITH MOST COVERAGE DURING THE LATE NIGHT.
ON FRIDAY...LOW PRESSURE FROM A NORTHERN STREAM SYSTEM WILL MOVE
INTO THE GREAT LAKES AND BRING A COLD FRONT INTO OUR AREA. A
SOUTHERN STREAM SYSTEM WILL REMAIN WELL TO THE SOUTHEAST OF THE
AREA.
SOME OF THE MOISTURE FROM THE SOUTHERN STREAM MAY MAKE IT INTO THE
AREA...BUT THE BULK OF IT WILL REMAIN SOUTHEAST. HOWEVER THE
NORTHERN SYSTEM WILL STILL HAVE ENOUGH MOISTURE TO WORK WITH TO GO
LIKELY POPS ALL AREAS.
THE FRONT WILL MOVE THROUGH THE AREA DURING THE DAY...TAKING THE
MOISTURE WITH IT. THUS ONLY EXPECT CHANCE POPS FRIDAY NIGHT. COLDER
AIR WILL HAVE MOVED IN...SO WENT MAINLY SNOW MOST AREAS FRIDAY
NIGHT. WITH LIMITED MOISTURE AVAILABLE...DO NOT EXPECT MUCH IF ANY
SNOW ACCUMULATION.
ON SATURDAY COLD ADVECTION WILL CONTINUE...AND THERE COULD BE A WEAK
SURFACE TROUGH IN THE AREA AS WELL. THUS FEEL THAT SLIGHT CHANCE
POPS FOR SNOW SHOWERS STILL LOOK GOOD FOR MOST OF THE AREA.
GENERALLY STAYED WITH A MODEL BLEND FOR TEMPERATURES THURSDAY NIGHT
INTO SATURDAY.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
ISSUED AT 151 PM EST WED JAN 13 2016
FOCUS LATE THIS WEEKEND AND EARLY NEXT WEEK WILL BE ON TEMPERATURES
AS AN ARCTIC AIRMASS IS EXPECTED TO INVADE THE LOWER GREAT LAKES AND
OHIO VALLEY FROM WESTERN CANADA. MEANWHILE...TEMPERATURE RECOVERY
AND PRECIPITATION CHANCES WILL BE THE TALKING POINTS BY WEDNESDAY
AS LOW LEVEL FLOW BECOMES SOUTHERLY AND UPPER FLOW MORE ZONAL.
THE OPERATIONAL MODELS HAVE BEEN INCONSISTENT WITH SYNOPTIC FEATURES
MODEL TO MODEL AND RUN TO RUN. SO...ENSEMBLE MEAN BLEND APPROACH PER
THE REGIONAL BLEND LOOKS GOOD. BLEND WILL START OFF WITH A COLD
UPPER LOW NEAR WESTERN LAKE SUPERIOR AND AN UPPER TROUGH NEAR
EASTERN TEXAS. AT THE SURFACE...ARCTIC AIR WILL BE FILTERING IN FROM
WESTERN CANADA. DECENT FORCING FROM GREAT LAKES UPPER LOW BUT
MARGINAL MOISTURE SUPPORTS SMALL SNOW CHANCES PER THE REGIONAL BLEND
THROUGH SUNDAY. THEN...AS THE UPPER LOW MOVES INTO QUEBEC AND THE
ARCTIC AIR BUILDS IN...DRY WEATHER IS EXPECTED THROUGH TUESDAY
NIGHT. UPPER FLOW WILL BE MORE ZONAL TOWARD WEDNESDAY WHICH COULD
BRING A SURFACE FRONT CLOSE ENOUGH FOR SOME SHOWERS BY WEDNESDAY.
BIG DIFFERENCES IN OPERATIONAL GFS AND ECMWF 850 MILLIBAR AND
SURFACE TEMPERATURES. THE ECWMF IS SOME 5 DEGREES OR SO COLDER AT
12Z SUNDAY WITH 15 DEGREES BELOW ZERO CELSIUS ACROSS OUR SOUTHEAST
AND 21 DEGREES CELSIUS BELOW ACROSS OUR NORTHWEST. MEANWHILE...THE
COLDEST AIR OF THE WEEKEND WILL BE OVER THE AREA SUNDAY AFTERNOON
WITH 850 MILLIBAR TEMPERATURES AS COLD AS 28 DEGREES BELOW. WITH
SOME CLEARING POSSIBLE SUNDAY NIGHT...BELOW ZERO OVERNIGHT LOWS
CERTAINLY LOOK POSSIBLE...ESPECIALLY IF THERE IS ANY SNOW ON THE
GROUND. AFTER SUNDAY NIGHT...TEMPERATURES WILL START REBOUNDING. THE
ECMWF IS QUICKER TO BRING THE MORE MILD AIR IN FROM THE GULF AS THE
ARCTIC HIGH SHIFTS TO THE EAST NEXT MONDAY NIGHT INTO TUESDAY. WITH
CONFIDENCE LOW ON TEMPERATURES...BEING DAYS 6 AND 7 AND WITH MODEL
INCONSISTENCIES...WILL ACCEPT THE REGIONAL BLEND WHICH SUGGESTS NEAR
AND ABOVE FREEZING TEMPERATURES ARE POSSIBLE BY WEDNESDAY. THIS ALSO
HINTS SOUTHERN AREAS OF THE FORECAST AREA COULD SEE A MIX AT THAT
TIME WITH MOSTLY SNOW NORTH.
&&
.AVIATION /DISCUSSION FOR THE 140000Z TAFS/...
ISSUED AT 542 PM EST WED JAN 13 2016
AREA OF SCT-BKN CLOUDS NEAR 040 CURRENTLY OVER NORTHERN ILLINOIS EXPECTED
TO PUSH OVER THE TERMINALS FOR A PERIOD THIS EVENING. BEST CHANCE FOR
A CEILING NEAR THIS LEVEL WILL BE AT KLAF. SHORT TERM MODELS INDICATE DRYING
NEAR THIS LEVEL LATER TONIGHT...SO THESE CLOUDS SHOULD DISSIPATE PRIOR TO
140600Z.
LINGERING SURFACE WIND GUSTS EXPECTED TO DIMINISH WITH SUNSET. AFTER
SUNSET SURFACE WINDS 200-230 DEGREES AT 5-10 KTS.
NO VISIBILITY RESTRICTIONS EXPECTED TONIGHT.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...50
NEAR TERM...50
SHORT TERM...50
LONG TERM....MK
AVIATION...JAS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
344 PM EST WED JAN 13 2016
.UPDATE...
AVIATION SECTION UPDATED
&&
.SYNOPSIS...
ISSUED AT 231 PM EST WED JAN 13 2016
A LOW PRESSURE SYSTEM WILL BRING RAIN TO THE AREA THURSDAY NIGHT
INTO FRIDAY...ALONG WITH SOME SNOW CHANCES FRIDAY NIGHT. MUCH COLDER
AIR WILL MOVE IN STARTING SATURDAY...AND SOME LIGHT SNOW IS POSSIBLE
INTO SUNDAY AS THE COLD AIR MOVES IN. SOME LIGHT PRECIPITATION IS
POSSIBLE NEXT WEDNESDAY WITH ANOTHER SYSTEM. THE COLDER AIR WILL
MODERATE SOME MID WEEK NEXT WEEK.
&&
.NEAR TERM.../REST OF THIS AFTERNOON AND TONIGHT/
ISSUED AT 231 PM EST WED JAN 13 2016
AN UPPER WAVE IS GENERATING SOME LIGHT SNOW ACROSS MAINLY THE
NORTHERN THIRD OF THE AREA THIS AFTERNOON...WITH SCATTERED LIGHT
SNOW SHOWERS ACROSS THE REMAINDER OF THE NORTHERN HALF.
THE SNOW WILL MOVE QUICKLY EAST THIS AFTERNOON. HRRR MODEL SHOWING
PERHAPS SOME LINGERING SNOW SHOWERS ACROSS THE FAR NORTHEAST AT
00Z...SO KEPT TOKEN 20 POPS THERE FOR AN HOUR OR TWO. OTHERWISE THE
NIGHT WILL BE DRY WITH A LACK OF FORCING.
HOWEVER...WARM ADVECTION BEGINS...SO TEMPERATURES WILL GRADUALLY
WARM OVERNIGHT. LOW TEMPERATURES WILL THUS LIKELY OCCUR NEAR 00Z.
WITH THE WARM ADVECTION ALOFT EXPECT SOME MID AND HIGH CLOUDS AT
TIMES DURING THE NIGHT. SOME CONCERN ABOUT LOW CLOUDS DEVELOPING
LATER TONIGHT AS DEWPOINTS RISE...BUT AM NOT CONFIDENT ENOUGH TO
INCLUDE AT THIS TIME.
&&
.SHORT TERM.../THURSDAY THROUGH SATURDAY/
ISSUED AT 231 PM EST WED JAN 13 2016
FOCUS IS ON CHANCES FOR PRECIPITATION. OVERALL MODELS ARE CLOSE
ENOUGH THAT A BLEND WAS USED.
WARM ADVECTION CONTINUES ON THURSDAY...BUT NOT ENOUGH FORCING OR
MOISTURE AROUND FOR ANY PRECIPITATION. WENT A LITTLE COOLER THAN MOS
FOR HIGH TEMPERATURES GIVEN THE SNOW COVER AND COLD GROUND.
ISENTROPIC LIFT INCREASES THURSDAY NIGHT AHEAD OF AN APPROACHING
SYSTEM...BUT FORCING/MOISTURE REMAIN RELATIVELY LIMITED. WILL ONLY
GO SLIGHT CHANCE POPS...WITH MOST COVERAGE DURING THE LATE NIGHT.
ON FRIDAY...LOW PRESSURE FROM A NORTHERN STREAM SYSTEM WILL MOVE
INTO THE GREAT LAKES AND BRING A COLD FRONT INTO OUR AREA. A
SOUTHERN STREAM SYSTEM WILL REMAIN WELL TO THE SOUTHEAST OF THE
AREA.
SOME OF THE MOISTURE FROM THE SOUTHERN STREAM MAY MAKE IT INTO THE
AREA...BUT THE BULK OF IT WILL REMAIN SOUTHEAST. HOWEVER THE
NORTHERN SYSTEM WILL STILL HAVE ENOUGH MOISTURE TO WORK WITH TO GO
LIKELY POPS ALL AREAS.
THE FRONT WILL MOVE THROUGH THE AREA DURING THE DAY...TAKING THE
MOISTURE WITH IT. THUS ONLY EXPECT CHANCE POPS FRIDAY NIGHT. COLDER
AIR WILL HAVE MOVED IN...SO WENT MAINLY SNOW MOST AREAS FRIDAY
NIGHT. WITH LIMITED MOISTURE AVAILABLE...DO NOT EXPECT MUCH IF ANY
SNOW ACCUMULATION.
ON SATURDAY COLD ADVECTION WILL CONTINUE...AND THERE COULD BE A WEAK
SURFACE TROUGH IN THE AREA AS WELL. THUS FEEL THAT SLIGHT CHANCE
POPS FOR SNOW SHOWERS STILL LOOK GOOD FOR MOST OF THE AREA.
GENERALLY STAYED WITH A MODEL BLEND FOR TEMPERATURES THURSDAY NIGHT
INTO SATURDAY.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
ISSUED AT 151 PM EST WED JAN 13 2016
FOCUS LATE THIS WEEKEND AND EARLY NEXT WEEK WILL BE ON TEMPERATURES
AS AN ARCTIC AIRMASS IS EXPECTED TO INVADE THE LOWER GREAT LAKES AND
OHIO VALLEY FROM WESTERN CANADA. MEANWHILE...TEMPERATURE RECOVERY
AND PRECIPITATION CHANCES WILL BE THE TALKING POINTS BY WEDNESDAY
AS LOW LEVEL FLOW BECOMES SOUTHERLY AND UPPER FLOW MORE ZONAL.
THE OPERATIONAL MODELS HAVE BEEN INCONSISTENT WITH SYNOPTIC FEATURES
MODEL TO MODEL AND RUN TO RUN. SO...ENSEMBLE MEAN BLEND APPROACH PER
THE REGIONAL BLEND LOOKS GOOD. BLEND WILL START OFF WITH A COLD
UPPER LOW NEAR WESTERN LAKE SUPERIOR AND AN UPPER TROUGH NEAR
EASTERN TEXAS. AT THE SURFACE...ARCTIC AIR WILL BE FILTERING IN FROM
WESTERN CANADA. DECENT FORCING FROM GREAT LAKES UPPER LOW BUT
MARGINAL MOISTURE SUPPORTS SMALL SNOW CHANCES PER THE REGIONAL BLEND
THROUGH SUNDAY. THEN...AS THE UPPER LOW MOVES INTO QUEBEC AND THE
ARCTIC AIR BUILDS IN...DRY WEATHER IS EXPECTED THROUGH TUESDAY
NIGHT. UPPER FLOW WILL BE MORE ZONAL TOWARD WEDNESDAY WHICH COULD
BRING A SURFACE FRONT CLOSE ENOUGH FOR SOME SHOWERS BY WEDNESDAY.
BIG DIFFERENCES IN OPERATIONAL GFS AND ECMWF 850 MILLIBAR AND
SURFACE TEMPERATURES. THE ECWMF IS SOME 5 DEGREES OR SO COLDER AT
12Z SUNDAY WITH 15 DEGREES BELOW ZERO CELSIUS ACROSS OUR SOUTHEAST
AND 21 DEGREES CELSIUS BELOW ACROSS OUR NORTHWEST. MEANWHILE...THE
COLDEST AIR OF THE WEEKEND WILL BE OVER THE AREA SUNDAY AFTERNOON
WITH 850 MILLIBAR TEMPERATURES AS COLD AS 28 DEGREES BELOW. WITH
SOME CLEARING POSSIBLE SUNDAY NIGHT...BELOW ZERO OVERNIGHT LOWS
CERTAINLY LOOK POSSIBLE...ESPECIALLY IF THERE IS ANY SNOW ON THE
GROUND. AFTER SUNDAY NIGHT...TEMPERATURES WILL START REBOUNDING. THE
ECMWF IS QUICKER TO BRING THE MORE MILD AIR IN FROM THE GULF AS THE
ARCTIC HIGH SHIFTS TO THE EAST NEXT MONDAY NIGHT INTO TUESDAY. WITH
CONFIDENCE LOW ON TEMPERATURES...BEING DAYS 6 AND 7 AND WITH MODEL
INCONSISTENCIES...WILL ACCEPT THE REGIONAL BLEND WHICH SUGGESTS NEAR
AND ABOVE FREEZING TEMPERATURES ARE POSSIBLE BY WEDNESDAY. THIS ALSO
HINTS SOUTHERN AREAS OF THE FORECAST AREA COULD SEE A MIX AT THAT
TIME WITH MOSTLY SNOW NORTH.
&&
.AVIATION /DISCUSSION FOR THE 132100Z IND TAF UPDATE/...
RADAR TRENDS SHOW SHORT WAVE OVER NRN INDIANA AND LOWER MICHIGAN
EXITING THE AREA...AND REMAINING TO THE NORTH OF CENTRAL INDIANA.
FURTHERMORE SATELLITE SHOWS A FEW BREAKS IN THE OVERCAST UPSTREAM
ACROSS WESTERN INDIANA AND EASTERN ILLINOIS. THUS WILL CONTINUE
THE VFR CONDITIONS...REMOVING THE SNOW SHOWER MENTION AND TREND
TOWARD HIGHER CIGS BY 00Z.
PREVIOUS DISCUSSION BELOW
/DISCUSSION FOR 131800Z TAF ISSUANCE/...
ISSUED AT 1124 AM EST WED JAN 13 2016
MOSTLY VFR CONDITIONS THROUGH THE TAF PERIOD. HOWEVER...SNOW SHOWERS
COULD REDUCE CONDITIONS TO MVFR OR POSSIBLY BRIEF IFR...AT LAF
THROUGH 23Z.
AFTER 00Z TONIGHT THROUGH 18Z THURSDAY...EXPECT JUST SOME HIGH
CLOUDS AHEAD OF AN APPROACHING UPPER HIGH PLAINS RIDGE.
SOUTHWEST WINDS 8 TO 12 KNOTS THIS AFTERNOON WILL DROP OFF JUST A
LITTLE BIT OVERNIGHT.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...50
NEAR TERM...50
SHORT TERM...50
LONG TERM....MK
AVIATION...MK/JP
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
231 PM EST WED JAN 13 2016
.UPDATE...
THE SYNOPSIS...NEAR TERM...AND SHORT TERM SECTIONS HAVE BEEN
UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 231 PM EST WED JAN 13 2016
A LOW PRESSURE SYSTEM WILL BRING RAIN TO THE AREA THURSDAY NIGHT
INTO FRIDAY...ALONG WITH SOME SNOW CHANCES FRIDAY NIGHT. MUCH COLDER
AIR WILL MOVE IN STARTING SATURDAY...AND SOME LIGHT SNOW IS POSSIBLE
INTO SUNDAY AS THE COLD AIR MOVES IN. SOME LIGHT PRECIPITATION IS
POSSIBLE NEXT WEDNESDAY WITH ANOTHER SYSTEM. THE COLDER AIR WILL
MODERATE SOME MID WEEK NEXT WEEK.
&&
.NEAR TERM.../REST OF THIS AFTERNOON AND TONIGHT/
ISSUED AT 231 PM EST WED JAN 13 2016
AN UPPER WAVE IS GENERATING SOME LIGHT SNOW ACROSS MAINLY THE
NORTHERN THIRD OF THE AREA THIS AFTERNOON...WITH SCATTERED LIGHT
SNOW SHOWERS ACROSS THE REMAINDER OF THE NORTHERN HALF.
THE SNOW WILL MOVE QUICKLY EAST THIS AFTERNOON. HRRR MODEL SHOWING
PERHAPS SOME LINGERING SNOW SHOWERS ACROSS THE FAR NORTHEAST AT
00Z...SO KEPT TOKEN 20 POPS THERE FOR AN HOUR OR TWO. OTHERWISE THE
NIGHT WILL BE DRY WITH A LACK OF FORCING.
HOWEVER...WARM ADVECTION BEGINS...SO TEMPERATURES WILL GRADUALLY
WARM OVERNIGHT. LOW TEMPERATURES WILL THUS LIKELY OCCUR NEAR 00Z.
WITH THE WARM ADVECTION ALOFT EXPECT SOME MID AND HIGH CLOUDS AT
TIMES DURING THE NIGHT. SOME CONCERN ABOUT LOW CLOUDS DEVELOPING
LATER TONIGHT AS DEWPOINTS RISE...BUT AM NOT CONFIDENT ENOUGH TO
INCLUDE AT THIS TIME.
&&
.SHORT TERM.../THURSDAY THROUGH SATURDAY/
ISSUED AT 231 PM EST WED JAN 13 2016
FOCUS IS ON CHANCES FOR PRECIPITATION. OVERALL MODELS ARE CLOSE
ENOUGH THAT A BLEND WAS USED.
WARM ADVECTION CONTINUES ON THURSDAY...BUT NOT ENOUGH FORCING OR
MOISTURE AROUND FOR ANY PRECIPITATION. WENT A LITTLE COOLER THAN MOS
FOR HIGH TEMPERATURES GIVEN THE SNOW COVER AND COLD GROUND.
ISENTROPIC LIFT INCREASES THURSDAY NIGHT AHEAD OF AN APPROACHING
SYSTEM...BUT FORCING/MOISTURE REMAIN RELATIVELY LIMITED. WILL ONLY
GO SLIGHT CHANCE POPS...WITH MOST COVERAGE DURING THE LATE NIGHT.
ON FRIDAY...LOW PRESSURE FROM A NORTHERN STREAM SYSTEM WILL MOVE
INTO THE GREAT LAKES AND BRING A COLD FRONT INTO OUR AREA. A
SOUTHERN STREAM SYSTEM WILL REMAIN WELL TO THE SOUTHEAST OF THE
AREA.
SOME OF THE MOISTURE FROM THE SOUTHERN STREAM MAY MAKE IT INTO THE
AREA...BUT THE BULK OF IT WILL REMAIN SOUTHEAST. HOWEVER THE
NORTHERN SYSTEM WILL STILL HAVE ENOUGH MOISTURE TO WORK WITH TO GO
LIKELY POPS ALL AREAS.
THE FRONT WILL MOVE THROUGH THE AREA DURING THE DAY...TAKING THE
MOISTURE WITH IT. THUS ONLY EXPECT CHANCE POPS FRIDAY NIGHT. COLDER
AIR WILL HAVE MOVED IN...SO WENT MAINLY SNOW MOST AREAS FRIDAY
NIGHT. WITH LIMITED MOISTURE AVAILABLE...DO NOT EXPECT MUCH IF ANY
SNOW ACCUMULATION.
ON SATURDAY COLD ADVECTION WILL CONTINUE...AND THERE COULD BE A WEAK
SURFACE TROUGH IN THE AREA AS WELL. THUS FEEL THAT SLIGHT CHANCE
POPS FOR SNOW SHOWERS STILL LOOK GOOD FOR MOST OF THE AREA.
GENERALLY STAYED WITH A MODEL BLEND FOR TEMPERATURES THURSDAY NIGHT
INTO SATURDAY.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
ISSUED AT 151 PM EST WED JAN 13 2016
FOCUS LATE THIS WEEKEND AND EARLY NEXT WEEK WILL BE ON TEMPERATURES
AS AN ARCTIC AIRMASS IS EXPECTED TO INVADE THE LOWER GREAT LAKES AND
OHIO VALLEY FROM WESTERN CANADA. MEANWHILE...TEMPERATURE RECOVERY
AND PRECIPITATION CHANCES WILL BE THE TALKING POINTS BY WEDNESDAY
AS LOW LEVEL FLOW BECOMES SOUTHERLY AND UPPER FLOW MORE ZONAL.
THE OPERATIONAL MODELS HAVE BEEN INCONSISTENT WITH SYNOPTIC FEATURES
MODEL TO MODEL AND RUN TO RUN. SO...ENSEMBLE MEAN BLEND APPROACH PER
THE REGIONAL BLEND LOOKS GOOD. BLEND WILL START OFF WITH A COLD
UPPER LOW NEAR WESTERN LAKE SUPERIOR AND AN UPPER TROUGH NEAR
EASTERN TEXAS. AT THE SURFACE...ARCTIC AIR WILL BE FILTERING IN FROM
WESTERN CANADA. DECENT FORCING FROM GREAT LAKES UPPER LOW BUT
MARGINAL MOISTURE SUPPORTS SMALL SNOW CHANCES PER THE REGIONAL BLEND
THROUGH SUNDAY. THEN...AS THE UPPER LOW MOVES INTO QUEBEC AND THE
ARCTIC AIR BUILDS IN...DRY WEATHER IS EXPECTED THROUGH TUESDAY
NIGHT. UPPER FLOW WILL BE MORE ZONAL TOWARD WEDNESDAY WHICH COULD
BRING A SURFACE FRONT CLOSE ENOUGH FOR SOME SHOWERS BY WEDNESDAY.
BIG DIFFERENCES IN OPERATIONAL GFS AND ECMWF 850 MILLIBAR AND
SURFACE TEMPERATURES. THE ECWMF IS SOME 5 DEGREES OR SO COLDER AT
12Z SUNDAY WITH 15 DEGREES BELOW ZERO CELSIUS ACROSS OUR SOUTHEAST
AND 21 DEGREES CELSIUS BELOW ACROSS OUR NORTHWEST. MEANWHILE...THE
COLDEST AIR OF THE WEEKEND WILL BE OVER THE AREA SUNDAY AFTERNOON
WITH 850 MILLIBAR TEMPERATURES AS COLD AS 28 DEGREES BELOW. WITH
SOME CLEARING POSSIBLE SUNDAY NIGHT...BELOW ZERO OVERNIGHT LOWS
CERTAINLY LOOK POSSIBLE...ESPECIALLY IF THERE IS ANY SNOW ON THE
GROUND. AFTER SUNDAY NIGHT...TEMPERATURES WILL START REBOUNDING. THE
ECMWF IS QUICKER TO BRING THE MORE MILD AIR IN FROM THE GULF AS THE
ARCTIC HIGH SHIFTS TO THE EAST NEXT MONDAY NIGHT INTO TUESDAY. WITH
CONFIDENCE LOW ON TEMPERATURES...BEING DAYS 6 AND 7 AND WITH MODEL
INCONSISTENCIES...WILL ACCEPT THE REGIONAL BLEND WHICH SUGGESTS NEAR
AND ABOVE FREEZING TEMPERATURES ARE POSSIBLE BY WEDNESDAY. THIS ALSO
HINTS SOUTHERN AREAS OF THE FORECAST AREA COULD SEE A MIX AT THAT
TIME WITH MOSTLY SNOW NORTH.
&&
.AVIATION /DISCUSSION FOR 131800Z TAF ISSUANCE/...
ISSUED AT 1124 AM EST WED JAN 13 2016
MOSTLY VFR CONDITIONS THROUGH THE TAF PERIOD. HOWEVER...SNOW SHOWERS
COULD REDUCE CONDITIONS TO MVFR OR POSSIBLY BRIEF IFR...AT LAF
THROUGH 23Z.
AFTER 00Z TONIGHT THROUGH 18Z THURSDAY...EXPECT JUST SOME HIGH
CLOUDS AHEAD OF AN APPROACHING UPPER HIGH PLAINS RIDGE.
SOUTHWEST WINDS 8 TO 12 KNOTS THIS AFTERNOON WILL DROP OFF JUST A
LITTLE BIT OVERNIGHT.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...50
NEAR TERM...50
SHORT TERM...50
LONG TERM....MK
AVIATION...MK
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
602 PM EST WED JAN 13 2016
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 450 PM EST WED JAN 13 2016
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW TROF OVER SE CANADA AND
THE ERN CONUS...ANCHORED BY MID/UPPER LEVEL LOW CENTERED IN THE
VCNTY OF JAMES BAY. IN THE NW FLOW...SHORTWAVE DROPPING SE THRU NW
WI HAS GENERATED SOME -SN THAT IS MOVING ACROSS FAR WRN LAKE
SUPERIOR/NW WI AND PORTIONS OF W AND CNTRL UPPER MI. MEANWHILE...
WITH LATEST RAP ANALYSIS SHOWING 850MB TEMPS AROUND -20C OVER LAKE
SUPERIOR...LES CONTINUES AS WELL. BOUNDARY LAYER WINDS BACKED MORE
THAN EXPECTED LAST NIGHT...RESULTING IN THE CONVERGENCE ZONE AND
ASSOCIATED MDT/HVY SNOW BAND OVER WRN LAKE SUPERIOR INTO NW UPPER MI
LIFTING FARTHER N THAN PLANNED. THAT CONVERGENCE ZONE AND HVY SNOW
BAND IS STILL OVER THE LAKE AND KEWEENAW...CURRENTLY BTWN HOUGHTON
AND CALUMET AS OF 21Z.
WITH THE PASSING OF THE AFOREMENTIONED SHORTWAVE...THE CONVERGENCE
ZONE ACROSS THE KEWEENAW HAS BEEN DRIFTING S THIS AFTN. THE
SOUTHWARD DRIFT WILL CONTINUE...BUT THE CONVERGENCE WILL GRADUALLY
WEAKEN AS LOW-LEVEL WIND FIELD DIMINISHES UNDER WEAKENING PRES
GRADIENT ACROSS THE AREA. AS A RESULT...ONGOING HVY SNOW BAND WILL
DRIFT S OVER THE NEXT SEVERAL HRS...BUT OVERALL INTENSITY OF SNOW
WILL DIMINISH WITH TIME. OPTED TO KEEP LES ADVY FOR NRN HOUGHTON
COUNTY GOING UNTIL SCHEDULED EXPIRATION AT 00Z DUE TO HIGH SNOWFALL
RATES LIKELY ON THE ORDER OF 1-2IN/HR. SNOWFALL SHOULD BE LIGHTER BY
THE TIME IT REACHES ONTONAGON COUNTY IN A FEW HRS. MAY SEE A COUPLE
OF INCHES OF SNOW THERE THIS EVENING. TO THE E...SHORTWAVE COMBINED
WITH REFOCUSING OF CONVERGENCE HAS LED TO LES INCREASING IN
ORGANIZATION/INTENSITY OVER ERN LAKE SUPERIOR OVER THE LAST HR OR
SO. LOOKS LIKE THERE WILL BE ENOUGH NORTHERLY WIND PUSH ACROSS THE
LAKE TO SHIFT THE LES BACK INTO THE NE FCST AREA THIS EVENING. HAVE
PAINTED 2-3 INCHES OF SNOW ACCUMULATION NEAR THE SHORE FROM JUST E
OF MUNISING EASTWARD. ELSEWHERE...-SN/FLURRIES WILL END IN THE NEXT
FEW HRS...AND MAY SEE SOME CLEARING AWAY FROM DIMINISHING LES.
INTERIOR CNTRL HAS BEST CHC OF SEEING AT LEAST SOME PARTIAL CLEARING
FOR A WHILE. LOWERED TEMPS TOWARD THE LOWER END OF AVBL GUIDANCE
(BIAS CORRECTED CANADIAN MODELS)...RESULTING IN MINS A FEW DEGREES
BLO 0F. WITH LIGHT/CALM WINDS...WOULDN`T TAKE MUCH CLEARING OR A
VERY LONG DURATION OF MOSTLY CLEAR TO SEE TEMPS PLUNGE TO -10 TO
-15F OR LWR IN TRADITIONAL COLD SPOTS.
ON THU...ATTENTION TURNS TO SHORTWAVE TROF MOVING OUT OVER THE
NRN/CNTRL PLAINS. IN RESPONSE...WAA/ISENTROPIC ASCENT REGIME
DEVELOPS DOWNSTREAM INTO THE UPPER GREAT LAKES AS SHOWN BEST ON 285K
AND ESPECIALLY 290K SFC. WITH ADDITION TO SOME UPPER DIVERGENCE
PROVIDED BY THE RIGHT ENTRANCE OF UPPER JET AS WELL AS LOW/MID LEVEL
FGEN...EXPECT A BAND OF -SN TO STREAK OUT ACROSS THE NRN PLAINS INTO
THE UPPER GREAT LAKES...AFFECTING UPPER MI MAINLY IN THE AFTN HRS.
12Z CANADIAN MODELS/GFS AND ECMWF WERE IN VERY GOOD AGREEMENT ON
THIS SCENARIO. 12Z NAM WAS MUCH SLOWER IN NE PROGRESS OF PCPN...AND
THE NCEP HIGH RES WRF-NMM WAS A COMPLETE OUTLIER IN ONLY BRUSHING
THE FAR SCNTRL FCST AREA WITH PCPN THU NIGHT. 18Z NAM CAME IN LINE
WITH THE GFS/ECMWF/CANADIAN MODELS WHICH WERE USED AS THE BASIS FOR
FCST. RAISED POPS INTO THE LIKELY RANGE FOR AT LEAST A TIME FOR
NEARLY ALL OF THE FCST AREA THU AFTN. ALTHOUGH 290K SFC SHOWS MIXING
RATIOS OF UP TO 3G/KG AVBL...ASCENT IS NOT ESPECIALLY STRONG AND
SNOW TO WATER RATIOS WILL BE ON THE ORDER OF 15-1. FOR NOW...EXPECT
SNOW ACCUMULATIONS TO BE AROUND 1 INCH W AND ONE-HALF INCH E THU
AFTN.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 352 PM EST WED JAN 13 2016
...WIDESPREAD SNOW THU NIGHT INTO FRI WITH N/NW FLOW LAKE EFFECT
INTO THE WEEKEND...
TROUGHING ALOFT OVER EAST HALF OF CANADA WITH ADDITIONAL TROUGHING
EXPANDING FM CENTRAL CONUS TO EASTERN CONUS THIS WEEKEND. COLDER
CONDITIONS SHOULD MODERATE EARLY NEXT WEEK AS TROUGH AXIS MOVES TO
EASTERN CANADA AND HEIGHTS BEGIN RISING FM WESTERN CONUS TO GREAT
LAKES.
SHORTWAVE TROUGH CROSSING THE CENTRAL PLAINS ON THU NIGHT ALONG WITH
WEAKER LOW PRESSURE SYSTEM AROUND 1000MB WILL SPREAD LIGHT SNOW FM
NORTHERN MN INTO NORTHERN WI/UPPER MICHIGAN DUE TO ISENTROPIC ASCENT
AND WARM AIR ADVECTION WELL TO NORTH OF SFC WARM FRONT FM UPPER
MISSISSIPPI RIVER VALLEY TO LOWER GREAT LAKES. SNOW MAY BE ENHANCED
BY RIGHT ENTRANCE FORCING FM JET STREAK FM NW ONTARIO TO NEW ENGLAND.
MOST PERSISTENT SNOW FM THE SYSTEM ON THU NIGHT WILL BE OVER
KEWEENAW AND LAKE SUPERIOR. EASTERLY WINDS AHEAD OF APPROACHING SFC
LOW AND H85 TEMPS DOWN NEAR -10C WILL RESULT IN LAKE ENAHANCEMENT.
DGZ IS NARROW AND QUITE ELEVATED ABOVE H7 SO SLR/S AT LEAST FOR THU
NIGHT SHOULD HOLD IN THE 10-15:1 RANGE INSTEAD IN THE FLUFFIER 20:1
RANGE THAT WILL MOVE IN FOR FRI AND BEYOND.
BY FRI MORNING TROUGH ALOFT WILL BE ENTERING WESTERN GREAT LAKES
WHILE SFC LOW DEEPENS TO AROUND 997MB OVER NORTHERN LK MICHIGAN. LOW
CONTINUES TO DEEPEN TO 992MB BY FRI EVENING OVER NORTHERN LK
HURON/GEORGIAN BAY. THOUGH LARGER SCALE FORCING FM THE SHORTWAVE IN
TERMS OF DEEP LAYER Q-VECTOR CONVERGENCE DIMINISHES FROM WEST TO
EAST ON FRI...THE SHORTWAVE TROUGH/LOWER HEIGHTS IN THE VCNTY AND
WELL DEVELOPED COLD CONVEYOR BELT OF DEEPER MOISTURE THROUGH H7/H85-
H7 FRONTOGENESIS ACROSS MUCH OF NORTH HALF OF UPPER MICHIGAN SHOULD
KEEP LIGHT SNOW GOING OVER MOST OF CWA. SNOW WILL FALL MODERATE TO
POSSIBLY HEAVY NEAR LK SUPERIOR DUE TO LAKE ENHANCEMENT AND UPSLOPE
LIFT AS CYCLONIC NORTH/NORTHEAST WINDS ON BACK SIDE OF DEEPENING LOW
DRAW COLDER AIR INTO REGION WITH H85 TEMPS DROPPING BLO -10C.
PRELIMINARY INDICATIONS SUGGEST ADVISORIES WOULD BE NEEDED THU
NIGHT...ESPECIALLY OVER THE KEWEENAW WHERE MORE PERSISTENT SYNOPTIC
SNOW AND LAKE ENHANCEMENT OCCURS...THEN ON FRI/FRI NIGHT FOR WESTERN
AND NORTH CENTRAL UPPER MICHIGAN FOR THE LAKE ENHANCED SNOW.
SNOWFALL FOR ALL OF THESE AREAS MAY REACH THE 6 TO 8 INCH RANGE FOR
24 HOURS THU NIGHT THROUGH FRI. GUSTY WINDS WILL ALSO RESULT IN
BLSN...ESPECIALLY NEAR LK SUPERIOR ON FRI. WILL CONTINUE TO MENTION
IN THE HAZARDOUS WEATHER OUTLOOK.
INTO THE WEEKEND...PERSISTENCE WILL BE THE STORY. COLD AIR CONTINUES
TO FILTER FM CENTRAL CANADA ACROSS WESTERN GREAT LAKES. H85 TEMPS
SHOULD FALL BLO -20C ON SAT AND MAYBE AS LOW AS -24C ON SUN. AT THE
SFC...SHOULD SEE TEMPS IN THE 20S ON FRI FALL OFF INTO THE TEENS FRI
NIGHT INTO SAT THEN TUMBLE BACK DOWN INTO THE SINGLE DIGITS ABOVE
ZERO BY LATE SAT AFTN AND DOWN BLO ZERO SAT NIGHT...AT LEAST FOR THE
WEST INTERIOR. READINGS WILL STRUGGLE TO RISE ABOVE ZERO OVER FAR
WEST ON SUN. OVERALL THE AIRMASS OVER THE AREA WILL BE MODIFIED BY
LAKE SUPERIOR SINCE SFC RIDGE STAYS WELL TO THE WEST FM NORTHERN
CANADA TO THE NORTHERN PLAINS WHILE STRONG SFC LOW AFFECTS EAST
COAST. LAKE INDUCED TROUGH IS EXPECTED TO LINGER ACROSS MUCH OF THE
GREAT LAKES...REINFORCED BY STRONGER UPPER LOW DIVING ACROSS THE
GREAT LAKES WHICH WILL INTENSIFY THE BROAD TROUGHING ACROSS THE
GREAT LAKES. PREVIOUS SHIFT HAD LIKELY POPS FOR THE LAKE EFFECT
THROUGH THE WEEKEND FOR AREAS FAVORED BY NW WINDS. BASED ON LATEST
MODELS SAW NO REASON TO STRAY FM THOSE HIGHER POPS COMPARED TO LOWER
POPS THAT CONSENSUS OF THE MODELS GAVE. PURE LAKE EFFECT SETUP IS
TYPICALLY A TIME WHERE CONSENSUS POPS FM THE COARSER MODELS WILL
FALL SHORT.
COLD PATTERN WITH NW FLOW LAKE EFFECT BEGINS TO BREAK DOWN EARLY
NEXT WEEK. KEPT HIGHER POPS FOR AREAS FAVORED BY NW WINDS THROUGH
MON AND MON NIGHT THEN SHIFTED BACK TO CONSENSUS POPS AS TROUGHING
BEGINS TO RELAX. OVERALL LOOKS LIKE WARMING TREND WILL START UP OR
AT LEAST TEMPS WILL PUSH UP TO NEAR NORMAL. THOUGH LAKE EFFECT WILL
BE ON THE DECLINE...MAY BE WEAK WAVE IN FLATTENING FLOW ALOFT THAT
WOULD BRING SWATH OF LGT SNOW TO UPPER GREAT LAKES BY NEXT WED.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 602 PM EST WED JAN 13 2016
LAKE EFFECT SNOW SHOWERS WILL CONTINUE TO AFFECT KCMX UNTIL WINDS
BECOME LIGHT/VRBL LATE TONIGHT...BRINGING AN END TO THE SNOW
SHOWERS. IN GENERAL...IFR CONDITIONS WILL PREVAIL AT KCMX UNTIL LATE
TONIGHT. HOWEVER...TYPICAL FOR LAKE EFFECT...CONDITIONS WILL BE
VARIABLE. EXPECT SOME PERIODS OF MVFR AND LIFR AS WELL. AFTER THE
SNOW SHOWERS END...MVFR CIGS WILL LIKELY PERSIST AT KCMX INTO THU
AFTERNOON. AT KIWD...MVFR CONDITIONS SHOULD GENERALLY PREVAIL THRU
THE FCST PERIOD. AT KSAW...VFR CONDITIONS SHOULD PREVAIL THRU MOST
OF THE FCST PERIOD. BY LATE THU AFTERNOON...LIGHT SNOW MOVES IN WITH
THE NEXT SYSTEM AND CONDITIONS WILL DETERIORATE TO IFR AT ALL SITES.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 450 PM EST WED JAN 13 2016
NO GALES ARE EXPECTED THRU THIS WEEKEND. MUCH OF THE TIME...WINDS
WILL BE IN THE 15-25KT OR 20-30KT RANGE. WINDS WILL BE LIGHTEST LATE
TONIGHT/THU MORNING...MOSTLY UNDER 15KT. A SURGE OF ARCTIC AIR THIS
WEEKEND WILL BRING A RETURN OF MORE SIGNIFICANT FREEZING SPRAY AS
WELL.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST THIS EVENING FOR MIZ003.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...JLA
AVIATION...07
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
450 PM EST WED JAN 13 2016
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 450 PM EST WED JAN 13 2016
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW TROF OVER SE CANADA AND
THE ERN CONUS...ANCHORED BY MID/UPPER LEVEL LOW CENTERED IN THE
VCNTY OF JAMES BAY. IN THE NW FLOW...SHORTWAVE DROPPING SE THRU NW
WI HAS GENERATED SOME -SN THAT IS MOVING ACROSS FAR WRN LAKE
SUPERIOR/NW WI AND PORTIONS OF W AND CNTRL UPPER MI. MEANWHILE...
WITH LATEST RAP ANALYSIS SHOWING 850MB TEMPS AROUND -20C OVER LAKE
SUPERIOR...LES CONTINUES AS WELL. BOUNDARY LAYER WINDS BACKED MORE
THAN EXPECTED LAST NIGHT...RESULTING IN THE CONVERGENCE ZONE AND
ASSOCIATED MDT/HVY SNOW BAND OVER WRN LAKE SUPERIOR INTO NW UPPER MI
LIFTING FARTHER N THAN PLANNED. THAT CONVERGENCE ZONE AND HVY SNOW
BAND IS STILL OVER THE LAKE AND KEWEENAW...CURRENTLY BTWN HOUGHTON
AND CALUMET AS OF 21Z.
WITH THE PASSING OF THE AFOREMENTIONED SHORTWAVE...THE CONVERGENCE
ZONE ACROSS THE KEWEENAW HAS BEEN DRIFTING S THIS AFTN. THE
SOUTHWARD DRIFT WILL CONTINUE...BUT THE CONVERGENCE WILL GRADUALLY
WEAKEN AS LOW-LEVEL WIND FIELD DIMINISHES UNDER WEAKENING PRES
GRADIENT ACROSS THE AREA. AS A RESULT...ONGOING HVY SNOW BAND WILL
DRIFT S OVER THE NEXT SEVERAL HRS...BUT OVERALL INTENSITY OF SNOW
WILL DIMINISH WITH TIME. OPTED TO KEEP LES ADVY FOR NRN HOUGHTON
COUNTY GOING UNTIL SCHEDULED EXPIRATION AT 00Z DUE TO HIGH SNOWFALL
RATES LIKELY ON THE ORDER OF 1-2IN/HR. SNOWFALL SHOULD BE LIGHTER BY
THE TIME IT REACHES ONTONAGON COUNTY IN A FEW HRS. MAY SEE A COUPLE
OF INCHES OF SNOW THERE THIS EVENING. TO THE E...SHORTWAVE COMBINED
WITH REFOCUSING OF CONVERGENCE HAS LED TO LES INCREASING IN
ORGANIZATION/INTENSITY OVER ERN LAKE SUPERIOR OVER THE LAST HR OR
SO. LOOKS LIKE THERE WILL BE ENOUGH NORTHERLY WIND PUSH ACROSS THE
LAKE TO SHIFT THE LES BACK INTO THE NE FCST AREA THIS EVENING. HAVE
PAINTED 2-3 INCHES OF SNOW ACCUMULATION NEAR THE SHORE FROM JUST E
OF MUNISING EASTWARD. ELSEWHERE...-SN/FLURRIES WILL END IN THE NEXT
FEW HRS...AND MAY SEE SOME CLEARING AWAY FROM DIMINISHING LES.
INTERIOR CNTRL HAS BEST CHC OF SEEING AT LEAST SOME PARTIAL CLEARING
FOR A WHILE. LOWERED TEMPS TOWARD THE LOWER END OF AVBL GUIDANCE
(BIAS CORRECTED CANADIAN MODELS)...RESULTING IN MINS A FEW DEGREES
BLO 0F. WITH LIGHT/CALM WINDS...WOULDN`T TAKE MUCH CLEARING OR A
VERY LONG DURATION OF MOSTLY CLEAR TO SEE TEMPS PLUNGE TO -10 TO
-15F OR LWR IN TRADITIONAL COLD SPOTS.
ON THU...ATTENTION TURNS TO SHORTWAVE TROF MOVING OUT OVER THE
NRN/CNTRL PLAINS. IN RESPONSE...WAA/ISENTROPIC ASCENT REGIME
DEVELOPS DOWNSTREAM INTO THE UPPER GREAT LAKES AS SHOWN BEST ON 285K
AND ESPECIALLY 290K SFC. WITH ADDITION TO SOME UPPER DIVERGENCE
PROVIDED BY THE RIGHT ENTRANCE OF UPPER JET AS WELL AS LOW/MID LEVEL
FGEN...EXPECT A BAND OF -SN TO STREAK OUT ACROSS THE NRN PLAINS INTO
THE UPPER GREAT LAKES...AFFECTING UPPER MI MAINLY IN THE AFTN HRS.
12Z CANADIAN MODELS/GFS AND ECMWF WERE IN VERY GOOD AGREEMENT ON
THIS SCENARIO. 12Z NAM WAS MUCH SLOWER IN NE PROGRESS OF PCPN...AND
THE NCEP HIGH RES WRF-NMM WAS A COMPLETE OUTLIER IN ONLY BRUSHING
THE FAR SCNTRL FCST AREA WITH PCPN THU NIGHT. 18Z NAM CAME IN LINE
WITH THE GFS/ECMWF/CANADIAN MODELS WHICH WERE USED AS THE BASIS FOR
FCST. RAISED POPS INTO THE LIKELY RANGE FOR AT LEAST A TIME FOR
NEARLY ALL OF THE FCST AREA THU AFTN. ALTHOUGH 290K SFC SHOWS MIXING
RATIOS OF UP TO 3G/KG AVBL...ASCENT IS NOT ESPECIALLY STRONG AND
SNOW TO WATER RATIOS WILL BE ON THE ORDER OF 15-1. FOR NOW...EXPECT
SNOW ACCUMULATIONS TO BE AROUND 1 INCH W AND ONE-HALF INCH E THU
AFTN.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 352 PM EST WED JAN 13 2016
...WIDESPREAD SNOW THU NIGHT INTO FRI WITH N/NW FLOW LAKE EFFECT
INTO THE WEEKEND...
TROUGHING ALOFT OVER EAST HALF OF CANADA WITH ADDITIONAL TROUGHING
EXPANDING FM CENTRAL CONUS TO EASTERN CONUS THIS WEEKEND. COLDER
CONDITIONS SHOULD MODERATE EARLY NEXT WEEK AS TROUGH AXIS MOVES TO
EASTERN CANADA AND HEIGHTS BEGIN RISING FM WESTERN CONUS TO GREAT
LAKES.
SHORTWAVE TROUGH CROSSING THE CENTRAL PLAINS ON THU NIGHT ALONG WITH
WEAKER LOW PRESSURE SYSTEM AROUND 1000MB WILL SPREAD LIGHT SNOW FM
NORTHERN MN INTO NORTHERN WI/UPPER MICHIGAN DUE TO ISENTROPIC ASCENT
AND WARM AIR ADVECTION WELL TO NORTH OF SFC WARM FRONT FM UPPER
MISSISSIPPI RIVER VALLEY TO LOWER GREAT LAKES. SNOW MAY BE ENHANCED
BY RIGHT ENTRANCE FORCING FM JET STREAK FM NW ONTARIO TO NEW ENGLAND.
MOST PERSISTENT SNOW FM THE SYSTEM ON THU NIGHT WILL BE OVER
KEWEENAW AND LAKE SUPERIOR. EASTERLY WINDS AHEAD OF APPROACHING SFC
LOW AND H85 TEMPS DOWN NEAR -10C WILL RESULT IN LAKE ENAHANCEMENT.
DGZ IS NARROW AND QUITE ELEVATED ABOVE H7 SO SLR/S AT LEAST FOR THU
NIGHT SHOULD HOLD IN THE 10-15:1 RANGE INSTEAD IN THE FLUFFIER 20:1
RANGE THAT WILL MOVE IN FOR FRI AND BEYOND.
BY FRI MORNING TROUGH ALOFT WILL BE ENTERING WESTERN GREAT LAKES
WHILE SFC LOW DEEPENS TO AROUND 997MB OVER NORTHERN LK MICHIGAN. LOW
CONTINUES TO DEEPEN TO 992MB BY FRI EVENING OVER NORTHERN LK
HURON/GEORGIAN BAY. THOUGH LARGER SCALE FORCING FM THE SHORTWAVE IN
TERMS OF DEEP LAYER Q-VECTOR CONVERGENCE DIMINISHES FROM WEST TO
EAST ON FRI...THE SHORTWAVE TROUGH/LOWER HEIGHTS IN THE VCNTY AND
WELL DEVELOPED COLD CONVEYOR BELT OF DEEPER MOISTURE THROUGH H7/H85-
H7 FRONTOGENESIS ACROSS MUCH OF NORTH HALF OF UPPER MICHIGAN SHOULD
KEEP LIGHT SNOW GOING OVER MOST OF CWA. SNOW WILL FALL MODERATE TO
POSSIBLY HEAVY NEAR LK SUPERIOR DUE TO LAKE ENHANCEMENT AND UPSLOPE
LIFT AS CYCLONIC NORTH/NORTHEAST WINDS ON BACK SIDE OF DEEPENING LOW
DRAW COLDER AIR INTO REGION WITH H85 TEMPS DROPPING BLO -10C.
PRELIMINARY INDICATIONS SUGGEST ADVISORIES WOULD BE NEEDED THU
NIGHT...ESPECIALLY OVER THE KEWEENAW WHERE MORE PERSISTENT SYNOPTIC
SNOW AND LAKE ENHANCEMENT OCCURS...THEN ON FRI/FRI NIGHT FOR WESTERN
AND NORTH CENTRAL UPPER MICHIGAN FOR THE LAKE ENHANCED SNOW.
SNOWFALL FOR ALL OF THESE AREAS MAY REACH THE 6 TO 8 INCH RANGE FOR
24 HOURS THU NIGHT THROUGH FRI. GUSTY WINDS WILL ALSO RESULT IN
BLSN...ESPECIALLY NEAR LK SUPERIOR ON FRI. WILL CONTINUE TO MENTION
IN THE HAZARDOUS WEATHER OUTLOOK.
INTO THE WEEKEND...PERSISTENCE WILL BE THE STORY. COLD AIR CONTINUES
TO FILTER FM CENTRAL CANADA ACROSS WESTERN GREAT LAKES. H85 TEMPS
SHOULD FALL BLO -20C ON SAT AND MAYBE AS LOW AS -24C ON SUN. AT THE
SFC...SHOULD SEE TEMPS IN THE 20S ON FRI FALL OFF INTO THE TEENS FRI
NIGHT INTO SAT THEN TUMBLE BACK DOWN INTO THE SINGLE DIGITS ABOVE
ZERO BY LATE SAT AFTN AND DOWN BLO ZERO SAT NIGHT...AT LEAST FOR THE
WEST INTERIOR. READINGS WILL STRUGGLE TO RISE ABOVE ZERO OVER FAR
WEST ON SUN. OVERALL THE AIRMASS OVER THE AREA WILL BE MODIFIED BY
LAKE SUPERIOR SINCE SFC RIDGE STAYS WELL TO THE WEST FM NORTHERN
CANADA TO THE NORTHERN PLAINS WHILE STRONG SFC LOW AFFECTS EAST
COAST. LAKE INDUCED TROUGH IS EXPECTED TO LINGER ACROSS MUCH OF THE
GREAT LAKES...REINFORCED BY STRONGER UPPER LOW DIVING ACROSS THE
GREAT LAKES WHICH WILL INTENSIFY THE BROAD TROUGHING ACROSS THE
GREAT LAKES. PREVIOUS SHIFT HAD LIKELY POPS FOR THE LAKE EFFECT
THROUGH THE WEEKEND FOR AREAS FAVORED BY NW WINDS. BASED ON LATEST
MODELS SAW NO REASON TO STRAY FM THOSE HIGHER POPS COMPARED TO LOWER
POPS THAT CONSENSUS OF THE MODELS GAVE. PURE LAKE EFFECT SETUP IS
TYPICALLY A TIME WHERE CONSENSUS POPS FM THE COARSER MODELS WILL
FALL SHORT.
COLD PATTERN WITH NW FLOW LAKE EFFECT BEGINS TO BREAK DOWN EARLY
NEXT WEEK. KEPT HIGHER POPS FOR AREAS FAVORED BY NW WINDS THROUGH
MON AND MON NIGHT THEN SHIFTED BACK TO CONSENSUS POPS AS TROUGHING
BEGINS TO RELAX. OVERALL LOOKS LIKE WARMING TREND WILL START UP OR
AT LEAST TEMPS WILL PUSH UP TO NEAR NORMAL. THOUGH LAKE EFFECT WILL
BE ON THE DECLINE...MAY BE WEAK WAVE IN FLATTENING FLOW ALOFT THAT
WOULD BRING SWATH OF LGT SNOW TO UPPER GREAT LAKES BY NEXT WED.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 102 PM EST WED JAN 13 2016
LAKE EFFECT SNOW SHOWERS WILL CONTINUE TO AFFECT KCMX UNTIL WINDS
BECOME LIGHT/VRBL LATE TONIGHT...BRINGING AN END TO THE SNOW
SHOWERS. IN GENERAL...IFR CONDITIONS WILL PREVAIL AT KCMX UNTIL LATE
TONIGHT. HOWEVER...TYPICAL FOR LAKE EFFECT...CONDITIONS WILL BE
VARIABLE. EXPECT SOME PERIODS OF MVFR AND LIFR AS WELL. AFTER THE
SNOW SHOWERS END...MVFR CIGS WILL LIKELY PERSIST AT KCMX THRU THU
MORNING. AT KIWD...MVFR CONDITIONS SHOULD GENERALLY PREVAIL THRU THE
FCST PERIOD. DISTURBANCE PASSING THRU THE AREA THIS AFTN WILL BRING
SOME -SN THAT MAY REDUCE VIS TO IFR AT TIMES. AT KSAW...VFR
CONDITIONS SHOULD PREVAIL THRU THE FCST PERIOD. SOME FLURRIES/-SN
WILL OCCUR THIS AFTN...AND NOT OUT OF THE QUESTION THAT CONDITIONS
COULD BRIEFLY FALL TO MVFR.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 450 PM EST WED JAN 13 2016
NO GALES ARE EXPECTED THRU THIS WEEKEND. MUCH OF THE TIME...WINDS
WILL BE IN THE 15-25KT OR 20-30KT RANGE. WINDS WILL BE LIGHTEST LATE
TONIGHT/THU MORNING...MOSTLY UNDER 15KT. A SURGE OF ARCTIC AIR THIS
WEEKEND WILL BRING A RETURN OF MORE SIGNIFICANT FREEZING SPRAY AS
WELL.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST THIS EVENING FOR MIZ003.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...JLA
AVIATION...ROLFSON
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
342 PM EST WED JAN 13 2016
.DISCUSSION...
WIDESPREAD LIGHT SNOW IS ONGOING FROM MINNESOTA TO LOWER MICHIGAN AT
PRESS TIME IN ASSOCIATION WITH A COUPLE OF WEAK SHORTWAVES THAT ARE
BEING STEERED SOUTHEAST ACROSS THE GREAT LAKES AT PRESS TIME. THE
FIRST WAVE IN THE SEQUENCE HAS ELICITED A HEALTHY RESPONSE OF WARM
ADVECTION ALOFT AND A 40+KT LLJ THAT IS MODELED TO GRADUALLY
STRENGTHEN THROUGH THIS EVENING. THIS WILL PROVIDE A FOCUS FOR LIGHT
TO OCCASIONALLY MODERATE SNOWFALL MAINLY SOUTH OF THE M59 CORRIDOR
FOR THE NEXT FEW HOURS. THE SECOND WAVE IS EMBEDDED WITHIN THE LEFT
EXIT OF THE JET CENTERED OVER NORTHERN MINNESOTA AND WILL TRAIL THE
LEAD WAVE BY ONLY A FEW HOURS. WEAK DYNAMIC FORCING WILL CENTER
FURTHER NORTH POST-00Z AS MOIST ISENTROPIC ASCENT PROVIDES THE
PRIMARY FORCING THROUGH 03-04Z. THE CEILING ON AMOUNTS IS QUITE LOW
AS OVERALL PERIOD OF SNOW WILL BE SHORT LIVED...MAINLY AN INCH OR
LESS. HOWEVER, THERE IS SOME MINOR OVERACHIEVING POTENTIAL GIVEN A
FAVORABLE THERMODYNAMIC PROFILE FEATURING A SFC-650MB DGZ THAT
IS SHOWN BY THE RAP TO SUPERSATURATED UP TO 110%+ WRT ICE AT TIMES.
SECOND CONCERN WILL SHOW ITSELF IN THE NEXT HOUR OR TWO, AND THAT IS
THE POTENTIAL FOR LAKE EFFECT TO BECOME ESTABLISHED OVER MIDLAND/BAY
COUNTIES WITHIN FAVORABLY UNSTABLE LAKE MICHIGAN PLUME. MADE NO
CHANGES TO THE AFTERNOON UPDATE WHICH CARRIED AMOUNTS OF AROUND 2"
HERE. BACKING LOW-LEVEL FLOW IN THE 0-1KM LAYER WILL QUICKLY END ANY
LES POTENTIAL AFTER 00Z. WARMING OF THE COLUMN, INCLUDING SFC TEMPS
RISING INTO THE LOW/MID 20S, WILL LIFT THE EFFECTIVE DGZ INTO THE
DRY LAYER ALOFT AND END ANY LINGERING FLURRY POTENTIAL BY MORNING.
ATTENTION THEN TURNS TO THE LATE WEEK SYSTEM WHICH WILL TAKE PLACE
IN TWO PHASES. THE FIRST WILL BE ON THURSDAY WHEN THE DEPARTURE OF
TONIGHT`S TROUGH AXIS ALLOW THE AFOREMENTIONED JET CENTERED OVER
MINNESOTA TO ALIGN ZONALLY AS UPSTREAM RIDGING BUILDS IN ADVANCE OF
ENERGY EMERGING OVER THE FRONT RANGE OF THE ROCKIES. THIS WILL FORCE
A PERIOD OF PROLONGED WAA/ISENTROPIC ASCENT FUELED BY RIGHT ENTRANCE
DYNAMICS THURSDAY INTO THURSDAY NIGHT. MARGINALLY FAVORABLE
MICROPHYSICS AND GENERALLY WEAK ASCENT WILL FAVOR JUST LIGHT SNOW
ACCUMULATIONS (HALF INCH OR LESS) NORTH OF I-69 DURING THE DAYTIME
HOURS BEFORE MID-LEVEL RIDGING DRIES THE MID AND UPPER LEVELS.
SECOND PHASE OF THE SYSTEM WILL BE THE PASSAGE OF THE LOW OVER
NORTHERN LOWER MICHIGAN THURSDAY NIGHT THROUGH FRIDAY. WITH THE DEEP
SUBSIDENCE-INDUCED DRY LAYER IN PLACE TO BEGIN THURSDAY NIGHT,
DEVELOPING WARM ADVECTION IN THE LOW-LEVELS WILL LIKELY LEAD TO
WIDESPREAD DRIZZLE. UNTIL CONFIDENCE IS HIGHER, INCLUDED A
FLURRIES/DRIZZLE MENTION. HOWEVER, IF UPSTREAM OBSERVATIONS CONFIRM
MODEL SUGGESTIONS OF DRIZZLE POTENTIAL, THE FLURRIES EFFECTIVELY
BECOME THE PLACEHOLDER IN THE FORECAST FOR FREEZING DRIZZLE, WHICH
COULD LAST FOR SEVERAL HOURS NORTH OF M-59.
RAIN ASSOCIATED WITH COLD FROPA WILL SWEEP ACROSS THE CWA ON FRIDAY
AFTERNOON, ALTHOUGH ONGOING PHASING WITH A POTENT PIECE OF
SUBTROPICAL ENERGY OVER THE MID-ATLANTIC DOES YIELD INCREASED
UNCERTAINTY WITH REGARD TO MOISTURE AND TIMING EVEN FOR SOUTHEAST
MICHIGAN ON FRIDAY. TEMPERATURES WILL REMAIN SEASONABLE, RISING INTO
THE 30S AND THEN NEAR 40 ON THURSDAY AND FRIDAY.
A RETURN TO FRIGID TEMPERATURES AND LAKE EFFECT SNOW SHOWER ACTIVITY
IS LIKELY FOR THE WEEKEND. THIS WILL OCCUR AS A CLOSED UPPER LOW AND
ASSOCIATED POCKET OF COLD AIR /-20C AT 850 MB/ MIGRATES ACROSS THE
GREAT LAKES. THE BEST CHANCE FOR SNOW SHOWER ACTIVITY WILL BE
ACCOMPANIED BY LOBES OF VORTICITY ROTATING THROUGH TO ADD SYNOPTIC
SUPPORT TO LAKE EFFECT ACTIVITY...TIMING AT THIS POINT FAVORS
SATURDAY NIGHT AND SUNDAY...ALTHOUGH SNOW SHOWERS WILL LIKELY BE
AROUND IN SOME FASHION THE ENTIRE WEEKEND. NORTHWEST FLOW AND
SURFACE HIGH PRESSURE WILL RESULT IN LESS CLOUDS AND SNOW SHOWERS AS
WELL AS SLIGHTLY MILDER TEMPERATURES TUESDAY AND WEDNESDAY.
&&
.MARINE...
LOW PRESSURE WILL TRACK OVER THE NORTHERN GREAT LAKES
TONIGHT...BRINGING A CHANCE OF SNOW TO THE REGION. A BRIEF BREAK
WILL FOLLOW ON THURSDAY AS HIGH PRESSURE TRIES TO BUILD INTO THE
SOUTHERN GREAT LAKES. THE NEXT LOW PRESSURE SYSTEM ARRIVES FROM THE
WEST ON THURSDAY NIGHT AND FRIDAY. THIS LOW WILL CONTINUE TO DEEPEN
AS IT TRACKS OVER THE GREAT LAKES RESULTING IN INCREASING WINDS ON
FRIDAY NIGHT AND INTO SATURDAY. WIND GUSTS OVER LAKE HURON COULD
REACH GALE CRITERIA AND THEREFORE...A GALE WATCH HAS BEEN ISSUED FOR
THIS TIMEFRAME.
&&
.AVIATION...ISSUED 621 AM EST WED JAN 13 2016
SCATTERED LAKE EFFECT -SHSN WILL BREAK UP THIS MORNING WITHIN SSW
FLOW IN ADVANCE OF NEXT CLIPPER. HOWEVER...LIGHT SNOW WILL SPREAD
INTO TERMINALS WITH THIS NEXT SYSTEM BY 22Z-00Z WITH MVFR CIGS
COMMON AND IFR VSBYS QUITE POSSIBLE DURING A 4-6 HOUR PERIOD OF MOST
PERSISTENT SNOW THIS EVENING. GENERALLY MVFR CIGS WILL PERSIST INTO
TONIGHT EVEN AFTER MAIN LIGHT SNOW EXITS TO THE EAST AS -SHSN LINGER.
SW FLOW IN THE 10-12 KNOT RANGE WILL PERSIST THROUGHOUT THE FORECAST.
AT DTW...TERMINAL WILL REMAIN ON SOUTHERN EDGE OF LES -SHSN EARLY IN
THE FORECAST WITH LIGHT SNOW SPREADING BACK INTO AREA 23Z OR SO.
MVFR/LOWER VFR CIGS EARLY WILL EDGE BACK TO MVFR WITH CLIPPER THIS
EVENING WITH IFR VSBYS AT TIMES IN THE -SN.
//DTW THRESHOLD PROBABILITIES...
* HIGH FOR CIGS AOB 5KFT THROUGHOUT THE FORECAST
* HIGH FOR PTYPE OF SNOW
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...GALE WATCH FROM FRIDAY EVENING THROUGH SATURDAY AFTERNOON FOR
LHZ361>363-441-462-463.
LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
&&
$$
DISCUSSION...JVC/DT
MARINE.......RK
AVIATION.....DG
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1244 PM EST WED JAN 13 2016
.SYNOPSIS...
HEAVY LAKE EFFECT SNOW WILL CONTINUE TODAY IN PARTS OF CENTRAL NEW
YORK DOWNWIND OF LAKE ONTARIO...ESPECIALLY THE SYRACUSE METRO
AREA AND NORTHERN ONEIDA COUNTY. THE REST OF THE REGION WILL BE
COLD AND BRISK WITH SCATTERED SNOW SHOWERS OR FLURRIES FROM A LAKE
ERIE SNOW BAND. LIGHT SNOW IS POSSIBLE WITH ANOTHER CLIPPER SYSTEM
LATE TONIGHT INTO THURSDAY. A STRONGER SYSTEM IS EXPECTED FRIDAY
NIGHT THROUGH SATURDAY NIGHT WITH A MIX OF RAIN AND SNOW POSSIBLE.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
1110 AM UPDATE...
MADE SOME ADJUSTMENT TO THE FORECAST TO ACCOUNT FOR TRENDS ON
RADAR AND WIND FLOW FOR THE LAKE EFFECT BANDS FROM BOTH ERIE AND
ONTARIO. HEAVY SNOW WILL CONTINUE AS THE RADAR SHOWED
INTENSIFICATION WITH THE ONTARIO BAND THROUGH THE NEXT FEW HOURS
WITH A SLIGHT BUT STEADY NUDGE NORTH STARTING AROUND 1PM. LAKE
ERIE BAND DROPPING LIGHT SNOW WELL INTO CNY AND EVEN FAR NE PA
BEFORE DROPPING OFF NEAR I-81. HAVE ADJUSTED CLOUD COVER AND POPS
DOWN IN AREAS IN BETWEEN THE BANDS.
410 AM UPDATE...
HEAVY LAKE EFFECT SNOW IS ONGOING IN PARTS OF CENTRAL NEW YORK. AS
IS TYPICAL...THE BAND /OR AT TIMES BANDS/ IS FLUCTUATING IN
PLACEMENT BY THE HOUR. THIS IS OCCURRING WITH EACH PASSING RIPPLE
EMBEDDED WITHIN THE FLOW ON THE BACK SIDE OF THE UPPER TROUGH THAT
IS GRADUALLY LIFTING NORTHEAST. 1 TO 2 INCH PER HOUR SNOWFALL
RATES WILL CONTINUE WITHIN THE HEAVIEST BANDS EARLY THIS
MORNING...NOW SLAMMING THE SYRACUSE METRO AREA EAST TO ABOUT
VERONA...TO SOUTH OF UTICA. LOCAL CONDITIONS WILL VARY WIDELY WITH
ABRUPT NEAR WHITE-OUT CONDITIONS POSSIBLE AT TIMES. WEST WIND WILL
ALSO STILL GUST TO 30 MPH THROUGH THE MORNING WHICH WILL TEND TO
DRIFT THE DRY AND FLUFFY SNOW. THIS WILL MAKE IT A CHALLENGE TO
KEEP ROADS CLEAR...ESPECIALLY NORTH-SOUTH ORIENTED ROUTES.
AN INTERRUPTION IN INTENSITY MAY OCCUR AROUND MID MORNING...BEFORE
THE BAND REINVIGORATES EARLY AFTERNOON WHILE SHIFTING GRADUALLY
NORTH AND CATCHING A LONGER FETCH DOWN THE LENGTH OF LAKE ONTARIO.
THUS FAR...A TOO-FAR-SOUTHWARD BIAS HAS BEEN DEPICTED BY ARW NMM
HRRR AND RUC MODELS...WHICH HAS BEEN OBSERVED TO BE COMMON WITH
LAKE ONTARIO LAKE EFFECT EVENTS IN THE PAST. I HAVE CONTINUED TO
LEAN ON THE CANADIAN AND TO A LESSER DEGREE THE NAM FOR
EXPECTATIONS OF BAND PLACEMENT. THAT BEING SAID...THERE IS SOME
SORT OF SMALL MCV/VORTICITY FEATURE THAT WAS OBSERVED CROSSING
LAKE HURON TO THE ONTARIO PENINSULA...AND NOW GETTING INTO FAR
WESTERN LAKE ONTARIO. I SUSPECT THIS IS WHAT MAY CAUSE THE LAKE
EFFECT TO LOSE A LITTLE ORGANIZATION LATER THIS MORNING...WHICH
THE LATEST 06Z NAM ALSO SEEMS TO BE LATCHING ON.
EARLY THIS AFTERNOON LAKE EFFECT SHOULD BE AGAIN PRETTY STOUT
ALONG THE NY THRUWAY AT FIRST...BUT LIFTING NORTHWARD WITH TIME.
IT SHOULD BE NORTH OF SYRACUSE BY MID AFTERNOON...NORTH OF UTICA
BY MID-TO-LATE AFTERNOON...AND THEN EXIT NORTHERN ONEIDA COUNTY
EARLY EVENING.
FOR THE REST OF THE REGION...GENERALLY JUST A COLD BRISK DAY WITH
SCATTERED SNOW SHOWERS AND FLURRIES...MAINLY TWIN TIERS NORTHWARD.
TEMPERATURES WILL PRETTY MUCH HOLD IN THE UPPER TEENS-LOWER 20S.
LAKE ERIE BANDS WILL AT TIMES EXTEND ACROSS THE CENTRAL TWIN
TIERS TO PROVIDE LIGHT DUSTINGS OF SNOW...WHICH THE WIND WILL
EASILY PICK UP AND BLOW AROUND. THERE COULD BE AN INCH OR TWO
ACCUMULATION ESPECIALLY STEUBEN-YATES- SCHUYLER. T
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/...
LAKE ONTARIO BAND WILL SHIFT NORTH OF THE AREA THIS EVENING...BUT
ALREADY IN THIS BUSY PATTERN...THE WARM AIR ADVECTION SIDE OF
ANOTHER CLIPPER WILL MOVE IN LATE TONIGHT INTO THURSDAY MORNING.
THIS COULD PROVIDE FOR A QUICK DUSTING TO INCH OF VERY LIGHT SNOW
FOR A GOOD CHUNK OF THE AREA. THE SURFACE LOW OF THE CLIPPER WILL
PASS TO OUR NORTH...AND THE ASSOCIATED COLD FRONT WILL PRETTY MUCH
WASH OUT IN OUR VICINITY THURSDAY NIGHT WITH LITTLE IMPACT EXCEPT
PERHAPS SPOTTY FLURRIES.
ON FRIDAY...WHAT IS LEFT OF THE CLIPPER FRONTAL ZONE WILL
EFFECTIVELY TURN BACK INTO A WARM FRONT AND LIFT OUT OF THE
AREA...AS SOUTHWEST FLOW DEVELOPS WELL AHEAD OF A STRONGER LOW
THAT WILL MOVE INTO THE WESTERN GREAT LAKES. THE RESULTING WARM
AIR ADVECTION WILL BOOST TEMPERATURES INTO UPPER 30S-LOWER 40S
FRIDAY...WHICH APPEARS TO BE MAINLY DRY.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
STRONG DUAL LOW SYSTEM MOVES INTO THE NORTHEAST WITH A WARM
SECTOR AHEAD OF THE LOW ALLOWING FOR THE POTENTIAL OF MIXED
PRECIPITATION FRIDAY NIGHT AND SATURDAY. THE SYSTEM LIFTS TO THE
E/NE LATE SATURDAY AND ANOTHER COLD ARCTIC AIR MASS DROPS IN FROM
THE NW AND CHANGES THE PRECIP OVER TO ALL SNOW. SOME ACCUMULATION
ON THE BACK SIDE OF THE SYSTEM IS POSSIBLE.
THE INFLUX OF ANOTHER ARCTIC AIR MASS AND A W/NWLY FLOW REGIME
WILL ALLOW FOR A PERIOD OF LAKE EFFECT SNOW SHOWERS SUNDAY NIGHT
THROUGH TUESDAY. SIGNIFICANT SNOWFALL ACCUMULATIONS ARE POSSIBLE.
COOL TEMPERATURES ARE EXPECTED THURSDAY WITH HIGHS IN THE MID TO
UPPER 20S AND LOWS IN THE TEENS AND SINGLE DIGITS. A BRIEF PERIOD
OF MILD TEMPERATURES IS ANTICIPATED FRIDAY AND SATURDAY WITH HIGHS
IN THE MID TO UPPER 30S AND LOWS IN THE 20S. A COLD AIR MASS WILL
DROP IN LATE IN THE WEEKEND AND REMAIN IN PLACE INTO EARLY NEXT
WEEK WITH HIGHS IN THE 20S AND LOWS IN THE TEENS.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
INTENSE LAKE EFFECT BAND STILL AFFECTING KSYR BUT WE EXPECT
CONDITIONS TO IMPROVE BY THE MID TO LATE AFTERNOON (BY AROUND 21Z)
AS BAND MOVES NORTH. BEFORE THIS TIME BELOW ALTERNATE MIN TO EVEN
BELOW AIRPORT MIN CONDITIONS WILL CONTINUE. FOR KRME, EXPECT
CIGS/VISBYS TO GO DOWN TO IFR AROUND MID AFTERNOON AS LAKE EFFECT
BAND SHIFTS NORTH INTO THE AREA. REMAINING SITES SHOULD BE MAINLY
VFR THIS AFTERNOON THOUGH IF A BAND FROM ERIE MOVES IN KELM COULD
SEE A BRIEF PERIOD OF RESTRICTIONS.
FOR TONIGHT, LAKE EFFECT WILL HAVE MOVED OUT OF THE AREA BY AROUND 0Z.
HOWEVER EXPECT A CLIPPER SYSTEM TO MOVE IN OVERNIGHT AND BRING
LIGHT SNOW WITH GENERALLY MVFR CIGS/VISBYS. WE DID, HOWEVER, ADD
IN A TEMPO IFR GROUP FOR KITH/KBGM NEAR DAWN WHEN SNOW MAY BE JUST
A BIT HEAVIER. CLIPPER MOVES OUT FOR THURSDAY WITH MAINLY JUST
SOME UNRESTRICTIVE FLURRIES AROUND BUT MVFR CIGS LINGERING.
WINDS WILL BE W/NW 10-20 GUSTING TO 25 KTS THIS AFTERNOON
DIMINISHING TONIGHT.
.OUTLOOK...
THURS NIGHT-FRI...MAINLY MVFR DUE TO LOW CIGS.
SAT...MVFR/IFR IN RAIN/SNOW.
SUN - MON...MVFR/IFR POSSIBLE SNOW SHOWERS.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...LAKE EFFECT SNOW WARNING UNTIL 7 PM EST THIS EVENING FOR
NYZ009-018-036-037.
LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST THIS EVENING FOR
NYZ046.
&&
$$
SYNOPSIS...ABS
NEAR TERM...MDP
SHORT TERM...MDP
LONG TERM...BJT
AVIATION...PCF
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1113 AM EST WED JAN 13 2016
.SYNOPSIS...
HEAVY LAKE EFFECT SNOW WILL CONTINUE TODAY IN PARTS OF CENTRAL NEW
YORK DOWNWIND OF LAKE ONTARIO...ESPECIALLY THE SYRACUSE METRO
AREA AND NORTHERN ONEIDA COUNTY. THE REST OF THE REGION WILL BE
COLD AND BRISK WITH SCATTERED SNOW SHOWERS OR FLURRIES FROM A LAKE
ERIE SNOW BAND. LIGHT SNOW IS POSSIBLE WITH ANOTHER CLIPPER SYSTEM
LATE TONIGHT INTO THURSDAY. A STRONGER SYSTEM IS EXPECTED FRIDAY
NIGHT THROUGH SATURDAY NIGHT WITH A MIX OF RAIN AND SNOW POSSIBLE.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
1110 AM UPDATE...
MADE SOME ADJUSTEMENT TO THE FORECAST TO ACCOUNT FOR TRENDS ON
RADAR AND WIND FLOW FOR THE LAKE EFFECT BANDS FROM BOTH ERIE AND
ONTARIO. HEAVY SNOW WILL CONTINUE AS THE RADAR SHOWED
INTENSIFICATION WITH THE ONTARIO BAND THROUGH THE NEXT FEW HOURS
WITH A SLIGHT BUT STEADY NUDGE NORTH STARTING AROUND 1PM. LAKE
ERIE BAND DROPPING LIGHT SNOW WELL INTO CNY AND EVEN FAR NE PA
BEFORE DROPPING OFF NEAR I-81. HAVE ADJUSTED CLOUD COVER AND POPS
DOWN IN AREAS IN BETWEEN THE BANDS.
410 AM UPDATE...
HEAVY LAKE EFFECT SNOW IS ONGOING IN PARTS OF CENTRAL NEW YORK. AS
IS TYPICAL...THE BAND /OR AT TIMES BANDS/ IS FLUCTUATING IN
PLACEMENT BY THE HOUR. THIS IS OCCURRING WITH EACH PASSING RIPPLE
EMBEDDED WITHIN THE FLOW ON THE BACK SIDE OF THE UPPER TROUGH THAT
IS GRADUALLY LIFTING NORTHEAST. 1 TO 2 INCH PER HOUR SNOWFALL
RATES WILL CONTINUE WITHIN THE HEAVIEST BANDS EARLY THIS
MORNING...NOW SLAMMING THE SYRACUSE METRO AREA EAST TO ABOUT
VERONA...TO SOUTH OF UTICA. LOCAL CONDITIONS WILL VARY WIDELY WITH
ABRUPT NEAR WHITE-OUT CONDITIONS POSSIBLE AT TIMES. WEST WIND WILL
ALSO STILL GUST TO 30 MPH THROUGH THE MORNING WHICH WILL TEND TO
DRIFT THE DRY AND FLUFFY SNOW. THIS WILL MAKE IT A CHALLENGE TO
KEEP ROADS CLEAR...ESPECIALLY NORTH-SOUTH ORIENTED ROUTES.
AN INTERRUPTION IN INTENSITY MAY OCCUR AROUND MID MORNING...BEFORE
THE BAND REINVIGORATES EARLY AFTERNOON WHILE SHIFTING GRADUALLY
NORTH AND CATCHING A LONGER FETCH DOWN THE LENGTH OF LAKE ONTARIO.
THUS FAR...A TOO-FAR-SOUTHWARD BIAS HAS BEEN DEPICTED BY ARW NMM
HRRR AND RUC MODELS...WHICH HAS BEEN OBSERVED TO BE COMMON WITH
LAKE ONTARIO LAKE EFFECT EVENTS IN THE PAST. I HAVE CONTINUED TO
LEAN ON THE CANADIAN AND TO A LESSER DEGREE THE NAM FOR
EXPECTATIONS OF BAND PLACEMENT. THAT BEING SAID...THERE IS SOME
SORT OF SMALL MCV/VORTICITY FEATURE THAT WAS OBSERVED CROSSING
LAKE HURON TO THE ONTARIO PENINSULA...AND NOW GETTING INTO FAR
WESTERN LAKE ONTARIO. I SUSPECT THIS IS WHAT MAY CAUSE THE LAKE
EFFECT TO LOSE A LITTLE ORGANIZATION LATER THIS MORNING...WHICH
THE LATEST 06Z NAM ALSO SEEMS TO BE LATCHING ON.
EARLY THIS AFTERNOON LAKE EFFECT SHOULD BE AGAIN PRETTY STOUT
ALONG THE NY THRUWAY AT FIRST...BUT LIFTING NORTHWARD WITH TIME.
IT SHOULD BE NORTH OF SYRACUSE BY MID AFTERNOON...NORTH OF UTICA
BY MID-TO-LATE AFTERNOON...AND THEN EXIT NORTHERN ONEIDA COUNTY
EARLY EVENING.
FOR THE REST OF THE REGION...GENERALLY JUST A COLD BRISK DAY WITH
SCATTERED SNOW SHOWERS AND FLURRIES...MAINLY TWIN TIERS NORTHWARD.
TEMPERATURES WILL PRETTY MUCH HOLD IN THE UPPER TEENS-LOWER 20S.
LAKE ERIE BANDS WILL AT TIMES EXTEND ACROSS THE CENTRAL TWIN
TIERS TO PROVIDE LIGHT DUSTINGS OF SNOW...WHICH THE WIND WILL
EASILY PICK UP AND BLOW AROUND. THERE COULD BE AN INCH OR TWO
ACCUMULATION ESPECIALLY STEUBEN-YATES- SCHUYLER. T
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/...
LAKE ONTARIO BAND WILL SHIFT NORTH OF THE AREA THIS EVENING...BUT
ALREADY IN THIS BUSY PATTERN...THE WARM AIR ADVECTION SIDE OF
ANOTHER CLIPPER WILL MOVE IN LATE TONIGHT INTO THURSDAY MORNING.
THIS COULD PROVIDE FOR A QUICK DUSTING TO INCH OF VERY LIGHT SNOW
FOR A GOOD CHUNK OF THE AREA. THE SURFACE LOW OF THE CLIPPER WILL
PASS TO OUR NORTH...AND THE ASSOCIATED COLD FRONT WILL PRETTY MUCH
WASH OUT IN OUR VICINITY THURSDAY NIGHT WITH LITTLE IMPACT EXCEPT
PERHAPS SPOTTY FLURRIES.
ON FRIDAY...WHAT IS LEFT OF THE CLIPPER FRONTAL ZONE WILL
EFFECTIVELY TURN BACK INTO A WARM FRONT AND LIFT OUT OF THE
AREA...AS SOUTHWEST FLOW DEVELOPS WELL AHEAD OF A STRONGER LOW
THAT WILL MOVE INTO THE WESTERN GREAT LAKES. THE RESULTING WARM
AIR ADVECTION WILL BOOST TEMPERATURES INTO UPPER 30S-LOWER 40S
FRIDAY...WHICH APPEARS TO BE MAINLY DRY.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
STRONG DUAL LOW SYSTEM MOVES INTO THE NORTHEAST WITH A WARM
SECTOR AHEAD OF THE LOW ALLOWING FOR THE POTENTIAL OF MIXED
PRECIPITATION FRIDAY NIGHT AND SATURDAY. THE SYSTEM LIFTS TO THE
E/NE LATE SATURDAY AND ANOTHER COLD ARCTIC AIR MASS DROPS IN FROM
THE NW AND CHANGES THE PRECIP OVER TO ALL SNOW. SOME ACCUMULATION
ON THE BACK SIDE OF THE SYSTEM IS POSSIBLE.
THE INFLUX OF ANOTHER ARCTIC AIR MASS AND A W/NWLY FLOW REGIME
WILL ALLOW FOR A PERIOD OF LAKE EFFECT SNOW SHOWERS SUNDAY NIGHT
THROUGH TUESDAY. SIGNIFICANT SNOWFALL ACCUMULATIONS ARE POSSIBLE.
COOL TEMPERATURES ARE EXPECTED THURSDAY WITH HIGHS IN THE MID TO
UPPER 20S AND LOWS IN THE TEENS AND SINGLE DIGITS. A BRIEF PERIOD
OF MILD TEMPERATURES IS ANTICIPATED FRIDAY AND SATURDAY WITH HIGHS
IN THE MID TO UPPER 30S AND LOWS IN THE 20S. A COLD AIR MASS WILL
DROP IN LATE IN THE WEEKEND AND REMAIN IN PLACE INTO EARLY NEXT
WEEK WITH HIGHS IN THE 20S AND LOWS IN THE TEENS.
&&
.AVIATION /16Z WEDNESDAY THROUGH SUNDAY/...
HEAVY LAKE EFFECT SNOW WILL AFFECT KSYR-KRME WITH HIGHLY VARIABLE...AND
RESTRICTIVE FLIGHT CONDITIONS THIS MORNING. CONDITIONS ARE EXPECTED
TO IMPROVE TO VFR-MVFR THIS AFTERNOON AS SNOW SQUALLS LIFT NORTHEAST.
ELSEWHERE...GENERALLY BKN VFR CEILINGS WITH OCCASIONAL SNOW
SHOWERS BRINGING LESS THAN AN HOUR OF IFR VSBY/MVFR CIG TO THE
CENTRAL NEW YORK AIRPORTS AT ANY TIME. DID NOT COMPLICATE THE TAFS WITH
THESE INTERMITTENT RESTRICTIONS...ALTHOUGH PILOTS SHOULD BE AWARE
THAT IMC COULD QUICKLY DEVELOP WITHIN THE LOCAL PATTERN.
GOOD TO GO WITH VFR AT KAVP.
GUSTY WEST-NORTHWEST WINDS 15-30 KTS THIS MORNING EASES TO 5-15
KTS AND BACKS SOUTHWEST TONIGHT.
.OUTLOOK...
WED NGT...MVFR-IFR. PERIODS OF LIGHT SNOW.
THURS-FRI...MAINLY VFR.
SAT...MVFR/IFR IN RAIN/SNOW.
SUN...MVFR/IFR POSSIBLE SNOW SHOWERS.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...LAKE EFFECT SNOW WARNING UNTIL 7 PM EST THIS EVENING FOR
NYZ009-018-036-037.
LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST THIS EVENING FOR
NYZ046.
&&
$$
SYNOPSIS...ABS
NEAR TERM...MDP/ABS
SHORT TERM...MDP
LONG TERM...BJT
AVIATION...JAB
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1254 PM CST WED JAN 13 2016
.UPDATE...
ISSUED AT 1254 PM CST WED JAN 13 2016
WE INCREASED HIGH TEMPERATURES OVER SOUTHWEST AND SOUTH CENTRAL ND
WITH THIS UPDATE AS THE EASTWARD ADVANCE OF A SURFACE WARM FRONT
HAS ALLOWED EVEN BISMARCK TO RISE INTO THE LOWER 30S F AS OF 1845
UTC. DEEPER INTO THE COOLER AIR MASS FURTHER EAST...FOG IS BEING
REPORTED BY THE ROLLA AND RUGBY AWOS SITES...SO WE ADDED A MENTION
OF PATCHY FOG TO THOSE AREAS THROUGH THIS EVENING.
UPDATE ISSUED AT 953 AM CST WED JAN 13 2016
NO REAL CHANGE WITH THIS UPDATE...THOUGH WE DID UTILIZE A TIME-
LAGGED ENSEMBLE OF SHORT-RANGE MODEL GUIDANCE TO SLIGHTLY ALTER
HOURLY POPS LATE THIS AFTERNOON INTO THE EVENING. A TIME-LAGGED
ENSEMBLE OF THE LAST 3 RAP RUNS ACTUALLY SUGGESTS THE MELTING
LAYER ALOFT MAY NOT BE QUITE WARM ENOUGH FOR LIGHT FREEZING RAIN
POTENTIAL IN NORTHWEST ND LIKE WE HAVE ADVERTISED...BUT WE WILL
CERTAINLY KEEP IT IN THE FORECAST AS PRECIPITATION-TYPE ALGORITHM
OUTPUT FROM THE RAP AND OTHER GUIDANCE STILL SUPPORTS THE CHANCE.
UPDATE ISSUED AT 621 AM CST WED JAN 13 2016
NO SIGNIFICANT UPDATES THIS MORNING OTHER THAN TEMPERATURES. A
PATCH OF CLEAR SKIES ACROSS CENTRAL NORTH DAKOTA HAS ALLOWED
TEMPERATURES TO FALL INTO THE SINGLE DIGITS WHILE CLOUDS
ASSOCIATED WITH A QUICK MOVING SHORTWAVE IN EASTERN PORTION OF
CENTRAL NORTH DAKOTA HAVE CAUSED TEMPERATURES TO RISE THERE FROM
EARLIER LOWS IN THE SINGLE DIGITS. FARTHER WEST...MORE MILD AIR
HAS MOVED INTO THE FAR WEST WITH TEMPERATURES GENERALLY IN THE
TEENS NORTHWEST TO 20S SOUTHWEST. LIGHT SNOW HAS ENDED OVER
EASTERN PORTIONS OF CENTRAL NORTH DAKOTA. WILL UPDATE CURRENT LOW
TEMPERATURES AND BLEND THROUGH MID MORNING. UPDATED TEXT PRODUCTS
WILL BE SENT SHORTLY.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 242 AM CST WED JAN 13 2016
MAIN CONCERNS IN THE SHORT TERM IS PRECIPITATION TYPE...WHICH
COMES IN TWO DISTINCT AREAS...ONE AREA IN NORTHWEST THROUGH NORTH
CENTRAL/TURTLE MOUNTAINS LATER THIS AFTERNOON THROUGH TONIGHT...AND
THE SECOND AREA DEVELOPING AFTER MIDNIGHT INTO MID MORNING THURSDAY
ACROSS SOUTHWEST AND INTO SOUTH CENTRAL NORTH DAKOTA.
MODEL CONSENSUS ON TIMING AND COVERAGE OF PRECIPITATION STILL
SUSPECT...HOWEVER THE IDEA OF TWO PRECIPITATION AREAS WITH THE
POTENTIAL FOR BOTH LIGHT FREEZING RAIN AND SNOW IS WELL AGREED
UPON PER NAM/GFS/SREF BUFKIT SOUNDINGS. HENCE USED A BLEND OF
THESE SOUNDINGS FOR THE AREAS MENTIONED ABOVE TO ADJUST THE
GIVEN SUPERBLEND WEATHER GRIDS.
CURRENT SUITE OF SATELLITE IMAGERY SHOWS A BREAK IN THE OVERCAST
CONDITIONS FOR WESTERN AND MOST OF CENTRAL NORTH DAKOTA EARLY THIS
MORNING. THE EXCEPTION IS THE TURTLE MOUNTAINS AND INTO THE JAMES
RIVER VALLEY WHERE A FAST MOVING SHORTWAVE EXTENDING FROM SOUTHWEST
MANITOBA WAS GENERATING CLOUDS AND PERIODIC WAVES OF LIGHT SNOW
MOSTLY FROM ROLETTE COUNTY EASTWARD. THIS ACTIVITY WILL WANE
AFTER 12Z WEDS AS THE SHORTWAVE SHIFTS FARTHER EAST. HIGH CLOUDS
QUICKLY INCREASING ACROSS CENTRAL/EASTERN MONTANA INDICATIVE OF
THE NEXT SURGE OF WARM AIR ADVECTION. SHOULD SEE SOME SUNSHINE
EARLY TODAY THEN CLOUDING UP FROM NORTHWEST TO SOUTHEAST. A
BAROCLINIC ZONE WAS SITUATED FROM NORTHWEST INTO NORTH CENTRAL
NORTH DAKOTA/TURTLE MOUNTAINS...AND SOUTHEAST INTO THE NORTHERN
JAMES RIVER VALLEY THIS MORNING. EXPECT A DISTINCT HIGH TEMPERATURE
FORECAST TODAY WITH HIGHS IN THE LOWER 40S FAR SOUTHWEST TO MID-
TEENS IN THE TURTLE MOUNTAINS AS THE BAROCLINIC ZONE TIGHTENS UP
THIS AFTERNOON. A SURFACE LOW IN SOUTHEAST ALBERTA TODAY WILL
SHIFT INTO NORTHEAST MONTANA BY 06Z THURSDAY...THEN TO NEAR BEULAH
BY 12Z THURSDAY. FRONTOGENETICAL FORCING PER NAM INCREASES THIS
AFTERNOON ACROSS NORTHWEST NORTH DAKOTA. SUFFICIENT 850-300MB
OMEGA AND INCREASING SURFACE CONVERGENCE WILL LEAD TO A SLIGHT CHC
OF LIGHT FREEZING RAIN FAR NORTHWEST NORTH DAKOTA/CROSBY AREA BY
MID AFTERNOON INTO EARLY EVENING. PRECIPITATION WILL SPREAD EAST
ACROSS NORTH CENTRAL NORTH DAKOTA INTO THE TURTLE MOUNTAINS BEFORE
MIDNIGHT AND CONTINUE INTO EARLY THURSDAY MORNING. SNOWFALL
ACCUMULATIONS TONIGHT THROUGH 12Z THURSDAY WILL BE UP TO ONE INCH
FOR LOCATIONS NORTH AND EAST OF MINOT. THE THREAT OF LIGHT FREEZING
RAIN WILL EXTEND TO NEAR WILLISTON AND NEW TOWN WEDNESDAY EVENING
/00Z-03Z OR 6PM-9PM CST. THEREAFTER...THE LIGHT FREEZING RAIN THREAT
IN THE NORTH WILL END...AS THE MAIN PERCEPTION SHIELD SHIFTS EAST
INTO A MORE FAVORABLE REGIME FOR ALL SNOW. SOUNDINGS SUPPORT
PRECIPITATION AS ALL SNOW BY THE TIME THE PRECIPITATION REACHES
REACHES MINOT AND THE TURTLE MOUNTAINS.
AFTER MIDNIGHT...AS THE SURFACE LOW ENTERS WESTERN NORTH DAKOTA
AND BEGINS TO TRACK SOUTHEAST...THE BAROCLINIC ZONE WILL BEGIN TO
BE PULLED FROM NORTH TO SOUTH. AT THE SAME TIME ANOTHER SHORTWAVE
WILL SLIDE INTO SOUTHWESTERN NORTH DAKOTA FROM EASTERN MONTANA.
THE DICKINSON AND BISMARCK SOUNDINGS SUPPORT A POTENTIAL FOR A
LIGHT FREEZING RAIN MENTION FROM 09Z-15Z THURSDAY/3AM-9AM CST.
AT THIS TIME...NOT EXPECTING WIDESPREAD FREEZING RAIN NOR A HIGH
PROBABILITY/HIGH CONFIDENT FREEZING RAIN EVENT IN EITHER THE
NORTHWEST OR SOUTHWEST/SOUTH CENTRAL PRECIPITATION AREA. THUS
WILL CONTINUE TO MENTION THIS IN THE HAZARDOUS WEATHER OUTLOOK/HWO
AND LET THE DAYSHIFT HAVE ANOTHER LOOK AT THE DATA TO SEE IF THERE
ARE ANY SIGNIFICANT CHANGES FROM WHAT WAS MENTIONED ABOVE.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 242 AM CST WED JAN 13 2016
THE MAIN FORECAST HIGHLIGHT IN THE LONG TERM PERIOD WILL BE
PRECIPITATION CHANCES EARLY IN THE PERIOD...THEN WIND CHILL
HIGHLIGHTS AS WE MOVE THROUGH THE WEEKEND AND EARLY NEXT WEEK.
A SHORTWAVE TROUGH MOVING ONTO THE NORTHWEST U.S. COAST THIS MORNING
WILL MOVE ACROSS THE NORTHERN ROCKIES TODAY INTO TONIGHT AND INDUCE
SURFACE LOW PRESSURE IN THE LEE OF THE NORTHERN AND CANADIAN
ROCKIES. THE SURFACE LOW IS PROGGED TO BE OVER WESTERN NORTH DAKOTA
BY 12 UTC THURSDAY. THE LOW IS FORECAST TO TRACK SOUTHEAST INTO
SOUTHERN MINNESOTA BY 00 UTC FRIDAY. MODELS ARE IN PRETTY GOOD
AGREEMENT IN SHOWING SOME INTENSIFICATION OF THE MID-LEVEL WAVE AS
IT TRACKS ACROSS NORTH DAKOTA DURING THE DAY THURSDAY. IN
ADDITION...COLDER AIR WILL BEGIN TO DROP SOUTH FROM CANADA. THE
INTERACTION OF THE COLD AIR AND STRENGTHENING WAVE WILL HELP TO
INTENSIFY THE BAROCLINIC ZONE WHICH WILL LIE ACROSS NORTHERN NORTH
DAKOTA THURSDAY MORNING. THIS IS EXPECTED TO BRING A SWATH OF 1
TO 3 INCHES OF SNOW ACROSS THE NORTHWEST AND NORTH CENTRAL AND
INTO THE NORTHERN JAMES RIVER VALLEY FROM LATE WEDNESDAY NIGHT
THROUGH THE DAY ON THURSDAY. ALWAYS CONCERNED WITH A STRENGTHENING
WAVE ALONG A TIGHT BAROCLINIC ZONE AND THE POSSIBILITY OF SOME
FRONTOGENETICALLY INDUCED BANDS OF HIGHER SNOW AMOUNTS. WILL HAVE
TO MONITOR FOR THIS POSSIBILITY AS THE MESOSCALE MODELS REACH INTO
THIS TIMEFRAME. THE 06 UTC NAM IS ALSO A BIT INTERESTING SHOWING
SOME MESOSCALE BANDING WITH HIGHER QPF AMOUNTS. FOR NOW WILL
STICK WITH A MENTION OF 1-3 INCHES OF SNOW FROM WEDNESDAY NIGHT
THROUGH THURSDAY GENERALLY ALONG AND NORTH OF A LINE FROM
WILLISTON TO MINOT AND TO RUGBY...HARVEY AND CARRINGTON. AND MAY
MENTION SOME POSSIBLY LOCAL HIGHER AMOUNTS. ANYWHERE SOUTH OF
THIS LINE COULD SEE UP TO AN INCH OF SNOW DURING THE DAY THURSDAY
AS THE BAROCLINIC ZONE DROPS SOUTH THROUGH SOUTHWEST AND SOUTH
CENTRAL NORTH DAKOTA. FOR THE MOST PART PRECIPITATION REMAINS
ALONG AND NORTH OF THE BAROCLINIC ZONE...BUT THERE IS SOME
INDICATION...MAINLY WITH THE NAM...OF SOME LIGHT PRECIPITATION
PUSHING INTO SOUTHWEST AND SOUTH CENTRAL NORTH DAKOTA FROM LATE
WEDNESDAY NIGHT INTO THURSDAY MORNING. NAM AND GFS BUFKIT SOUNDING
SHOW THAT IF ANY PRECIPITATION THURSDAY MORNING WOULD FALL OVER
THE SOUTHWEST AND SOUTH CENTRAL...THERE WOULD BE A POTENTIAL FOR
SOME LIGHT FREEZING RAIN. THIS POTENTIAL WOULD END BY MID MORNING
ACROSS MOST OF THE SOUTHWEST AND SOUTH CENTRAL...WITH THE
EXCEPTION OF THE FAR SOUTHERN TIER COUNTIES...WHERE WARMER
TEMPERATURES AT THE SURFACE AND ALOFT MAY RESULT IN A RAIN SNOW
MIX INTO THE EARLY AFTERNOON. AT THIS TIME...WE WILL KEEP A
MENTION OF MIXED PRECIPITATION SOUTHWEST AND SOUTH CENTRAL...BUT
THE MODEL QPF AMOUNTS HERE ARE QUITE LIGHT...BUT WILL CERTAINLY
NEED TO MONITOR.
LIGHT SNOW IS THEN EXPECTED TO TAPER OFF THURSDAY EVENING AS COLD
ARCTIC AIR CONTINUES TO FILTER INTO THE STATE. ANOTHER WEAK WAVE
TRACKS ALONG THE BAROCLINIC ZONE ON FRIDAY...WHICH BY THIS TIME IS
OVER WESTERN TO SOUTH CENTRAL NORTH DAKOTA. FOR NOW OUR MULTI-MODEL
BLEND IS GIVING A SPATTERING OF SLIGHT CHANCE POPS ACROSS THE CWA
WHICH SEEMS REASONABLE. IF ANYTHING WE MAY NEED TO BUMP UP POPS
ACROSS THE SOUTHWEST BUT ENOUGH TIME TO SEE HOW LATER RUNS MANIFEST
THIS.
MAIN FOCUS FRIDAY NIGHT AND THROUGH THE WEEKEND WILL BE WIND CHILL
HIGHLIGHTS...MAINLY ALONG...NORTH AND EAST OF LAKE SAKAKAWEA AND THE
MISSOURI RIVER FRIDAY NIGHT-SATURDAY MORNING...THEN ACROSS THE CWA
SATURDAY NIGHT-SUNDAY MORNING. DEPENDING ON RESULTING TEMPERATURES
WE MAY NEED A WIND CHILL WARNING ACROSS THE NORTHEASTERN PORTION OF
THE CWA DURING THIS PERIOD. COLD AIR BEGINS TO ABATE BY EARLY NEXT
WEEK BUT WILL LIKELY SEE A LARGE RANGE OF TEMPERATURES BETWEEN THE
WARMER SOUTHWEST AND COLD NORTHEAST PORTION OF THE CWA.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1254 PM CST WED JAN 13 2016
LOCALIZED IFR TO LIFR CONDITIONS OVER PART OF NORTH CENTRAL ND TO
THE NORTHWEST OF KDVL WILL LIKELY CONTINUE THROUGH THE EVENING. A
BAND OF LIGHT SNOW WILL THEN DEVELOP OVER NORTH CENTRAL ND BY 00
UTC WITH LOWERING CEILINGS AND VISIBILITY. A LITTLE LIGHT FREEZING
RAIN IS POSSIBLE ON THE FRINGES OF THE SNOW...MAINLY IN NORTHWEST
ND. FLIGHT CONDITIONS WILL DETERIORATE FURTHER THURSDAY MORNING
WITH WIDESPREAD IFR TO LIFR CONDITIONS IN DEVELOPING LIGHT SNOW
ACROSS ALL OF WESTERN AND CENTRAL ND.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...CJS
SHORT TERM...KS
LONG TERM...TWH
AVIATION...CJS
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
415 PM EST WED JAN 13 2016
.SYNOPSIS...
AN UPPER LEVEL DISTURBANCE MOVING ACROSS THE GREAT LAKES WILL RESULT
IN SOME LIGHT SNOW INTO THIS EVENING...MAINLY ALONG AND NORTH OF
INTERSTATE 70. SOUTHERLY FLOW WILL ALLOW FOR A GRADUAL WARM UP
THURSDAY INTO FRIDAY. ANOTHER UPPER LEVEL DISTURBANCE WILL BRING
RAIN TO THE AREA ON FRIDAY.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
AN AREA OF LIGHT SNOW AND FLURRIES HAS SPREAD INTO NORTHERN
PORTIONS OF OUR FA THIS AFTERNOON IN ASSOCIATION WITH A WEAK
UPPER LEVEL DISTURBANCE. VSBYS HAVE BEEN OCCASIONALLY DROPPING
BELOW A COUPLE OF MILES...SO THINK SOME LIGHT ACCUMULATIONS WILL
BE POSSIBLE ACROSS OUR FAR NORTH...BUT SHOULD BE LESS THAN A HALF
INCH. EXPECT PCPN TO TAPER OF FROM WEST TO EAST THROUGH THIS
EVENING AS WE GET ON THE BACK SIDE OF THE DISTURBANCE. IN
DEVELOPING SOUTHERLY LOW LEVEL FLOW...EXPECT TEMPS TO SLOWLY RISE
UP INTO THE MID 20S OVERNIGHT.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/...
IN CONTINUED SOUTHERLY FLOW...LOW LEVEL MOISTURE WILL BE ON THE
INCREASE THROUGH THE MORNING HOURS ON THURSDAY. THE 12Z GFS IS
ACTUALLY THE MOST AGGRESSIVE WITH THIS...EVEN TRYING TO SQUEEZE
OUT SOME VERY LIGHT QPF THROUGH THE MORNING HOURS. THE 12Z NAM IS
ALSO TRYING TO SUGGEST THIS...BUT IS SHALLOWER WITH ITS NEAR
SURFACE SATURATED LAYER WHILE THE LATEST RAP IS EVEN LESS
IMPRESSIVE. AS A RESULT...THERE IS QUITE A BIT OF UNCERTAINTY IN
THE POSSIBILITY FOR SOME PATCHY FREEZING DRIZZLE/DRIZZLE THURSDAY
MORNING. SINCE IT IS TOUGH TO RULE IT OUT THOUGH AND IS ALREADY IN
THE FORECAST...WILL GO AHEAD AND HANG ON TO JUST A VERY LOW
CHANCE.
SOUTHERLY FLOW WILL CONTINUE TO INCREASE THURSDAY NIGHT INTO
FRIDAY AHEAD OF AN APPROACHING MID LEVEL SHORT WAVE. THIS WILL
ALLOW FOR DEEPER MOISTURE TO SPREAD NORTH INTO OUR AREA ON FRIDAY.
BETWEEN THIS AND SOME DEVELOPING ISENTROPIC LIFT...EXPECT TO SEE
SOME PCPN WORKING INTO OUR FAR SOUTHWEST POSSIBLY AS EARLY AS
LATE THURSDAY NIGHT AND THEN OVERSPREADING OUR AREA FRIDAY
MORNING AND CONTINUING INTO FRIDAY AFTERNOON. LOW LEVEL THERMAL
FIELDS OFF FORECAST SOUNDINGS SUGGEST THAT WE WILL BE WARM ENOUGH
FOR PRECIPITATION TO BE ALL LIQUID AT ONSET LATE THURSDAY
NIGHT/FRIDAY MORNING. SURFACE TEMPERATURES SHOULD ALSO BE ABOVE
FREEZING SO WILL KEEP PCPN ALL RAIN.
PCPN WILL BEGIN TO TAPER OFF FROM WEST TO EAST FRIDAY NIGHT AS
DRIER AIR FILTERS IN BEHIND A COLD FRONT MOVING THROUGH THE AREA.
AS THE COOLER AIR MOVES IN...SOME OF THE PCPN WILL MIX WITH AND
THEN CHANGE TO SNOW THROUGH THE NIGHT...BUT GIVEN THE DECREASING
MOISTURE...QPF AMOUNTS SHOULD BE FAIRLY LIGHT BY THEN.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
THE LONG TERM PERIOD STARTS OFF WITH LOW PRESSURE HEADING TOWARDS
THE NORTHEAST AND THE POTENTIAL FOR WRAP AROUND SNOW SATURDAY. A
STRONG UPPER LEVEL LOW WILL THEN BEGIN TO ROTATE SOUTHWARDS SATURDAY
EVENING INTO SUNDAY MORNING BRINGING AN ARCTIC COLD FRONT THROUGH
THE REGION. THERE ARE SOME SLIGHT DIFFERENCES BETWEEN THE EURO...
GFS... AND CMC WHICH ALL HAVE CORRESPONDING IMPACTS ON THE TIMING OF
THE ARCTIC FRONT AND IF THERE WILL BE ASSOCIATED PRECIPITATION.
DIFFERENCES START TO OCCUR EARLY SATURDAY MORNING AS A POTENT
SHORTWAVE DIPS DOWN INTO THE TEXAS PANHANDLE.
THE GFS STRENGTHENS THE SHORTWAVE AND STARTS TO SLOW IT DOWN AS IT
PUSHES EAST INTO LOUISIANA SATURDAY EVENING. THE EURO AND CANADIAN
KEEP THE SHORTWAVE MUCH WEAKER AND THE UPPER LEVEL LOW A TAD FURTHER
SOUTH. THE EURO/ CMC SOLUTION FAVORS THE ARCTIC COLD FRONT MOVING
THROUGH THE AREA SATURDAY EVENING. THE GFS SOLUTION HAS THE ARCTIC
FRONT MOVING THROUGH SUNDAY MORNING. GIVEN THE CMC AND EURO ARE A
RELATIVELY CLOSE MATCH HAVE LEANED TOWARDS THIS SOLUTION.
DURING THE DAY SUNDAY 850 MB TEMPERATURES BEGIN TO PLUMMET FROM -7
DEGREES C SATURDAY TO NEAR -20 DEGREES C SUNDAY. THIS WILL MAKE HIGH
TEMPERATURES IN THE TEENS POSSIBLE SUNDAY AS THICKNESSES QUICKLY
FALL. FOR NOW HAVE GONE AHEAD AND JUST TRENDED MAX TEMPS DOWN A BIT
TO FAVOR CMC/EURO. ALSO WITH THE FURTHER SOUTH UPPER LEVEL LOW TRACK
THERE LOOKS TO BE A CHANCE OF SNOW AS STRONG PVA MOVES ACROSS THE
AREA. HAVE BUMPED UP POPS TO CHANCE FOR SUNDAY. MONDAY MORNING
SURFACE HIGH PRESSURE WILL START TO MOVE INTO THE AREA AS THE BEST
AGEOSTROPHIC CONVERGENCE MOVES EAST TOWARDS THE REGION. HIGHS MONDAY
WILL BE WELL BELOW NORMAL AS THE MERCURY ONLY RISES TO THE MIDDLE
TEENS. THIS IS SUPPORTED BY 850 TEMPERATURES AGAIN FORECASTED TO BE
AROUND -20 DEGREES C.
TUESDAY INTO WEDNESDAY THE WARMING TREND WILL START TO COMMENCE AS
SURFACE HIGH PRESSURE SLOWLY SLIDES EAST OF OHIO ALLOWING SOUTHERLY
WINDS TO RETURN. LATE TUESDAY INTO EARLY WEDNESDAY A SHORTWAVE WILL
DIVE SOUTH INTO NORTHERN WISCONSIN AND JUST CLIP NORTHERN OHIO. FOR
NOW HAVE JUST ADDED SLIGHT CHANCE POPS ACROSS THE NORTH TO ACCOUNT
FOR THIS. DURING THE DAY WEDNESDAY MODELS ARE INDICATING A STRONG
SHORTWAVE TRYING TO WRAP UP OVER THE ROCKY MOUNTAINS. THIS LIKELY BE
THE NEXT STORM SYSTEM TO AFFECT THE AREA.
&&
.AVIATION /20Z WEDNESDAY THROUGH MONDAY/...
SURFACE HIGH PRESSURE CENTERED OVER THE TN VLY WILL SLIDE EAST
WITH WAA DEVELOPING ON ITS BACK SIDE. MID LEVEL CLOUDS VISIBLE
ON LATEST SATL IMGRY IN THIS REGION OF ISENTROPIC LIFT SHIFTING
EAST ACRS IL AND INDIANA INTO WESTERN OHIO. BEST MOISTURE/LIFT TO
STAY NORTH OF THE TAF SITES BUT A BRIEF PERIOD OF LIGHT SNOW OR
FLURRIES WILL BE PSBL AT KDAY AND KCMH/KLCK TOWARD 00Z. EXPECT VFR
CONDITIONS THRU MOST OF THE NIGHT AS MID LEVEL CLOUDS GIVE WAY TO
PARTIAL CLEARING. IN SOUTHERLY FLOW...LOW LEVEL MOISTURE INCREASES
TOWARD SUNRISE. HAVE INTRODUCED MVFR CIGS AT ALL TAF SITES.
OUTLOOK...MVFR CEILINGS ARE LIKELY THURSDAY NIGHT AND MVFR CIGS
AND VISIBILITIES LIKELY FRIDAY INTO SATURDAY. MVFR CEILINGS MAY
LINGER INTO SATURDAY NIGHT AND SUNDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...JGL
NEAR TERM...JGL
SHORT TERM...JGL
LONG TERM...FRANKS
AVIATION...AR
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
355 PM CST WED JAN 13 2016
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 355 PM CST WED JAN 13 2016
PRIMARY CONCERNS TONIGHT WILL DEAL WITH THE POTENTIAL FOR FOG INTO
THURSDAY MORNING...AS WELL AS DEGREE OF TEMPERATURE WARMING ON
THURSDAY.
THIS AFTERNOON...SOUTHWESTERLY WINDS HAVE PUSHED TEMPERATURES INTO
THE 30S IN MOST AREAS. AREAS OF THE FAR SOUTHERN CWA ADJACENT
TO THE SAND HILLS WILL CLIMB INTO THE LOWER 40S.
TONIGHT...HIGH RESOLUTION GUIDANCE CONTINUES TO SUGGEST WINDS SHOULD
WEAKEN AS THE EVENING PROGRESSES ON...WITH A STATIONARY BOUNDARY
FORMING ALONG A HON TO FSD TO STORM LAKE LINE. WEAK CONVERGENCE
ALONG THIS BOUNDARY COMBINED WITH CONTINUED WARM ADVECTION OVERTOP
THE COLD SNOWPACK WOULD FAVOR FOG DEVELOPMENT ESPECIALLY SOUTH OF
THE BUFFALO RIDGE AFTER MIDNIGHT. WE WILL NEED TO WAIT FOR A BROAD
MID-LVL CLOUD DECK TO SLIDE EASTWARD...WHICH WILL ALLOW TEMPERATURES
TO DROP QUICKLY. ONCE TEMPERATURES BEGIN TO DROP...FOG COULD QUICKLY
BECOME DENSE ESPECIALLY ACROSS THE EASTERN HALF OF THE TRI-STATE
AREA. SREF PROBABILITIES SUGGEST RATHER HIGH PROBABILITIES OF
VISIBILITY LESS THAN 1 MILE...BUT THE COVERAGE OF THOSE VISIBILITIES
IS IN DOUBT.
ANOTHER WARM DAY IS EXPECTED ON THURSDAY...BUT POTENTIAL DOES EXIST
THAT FOG MAY FORM INTO A STRATUS DECK OVER THE NERN HALF OF THE CWA.
TEMPERATURES WILL AGAIN CLIMB INTO THE 30S BY THE AFTERNOON.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 355 PM CST WED JAN 13 2016
THE INITIAL ARTIC PUSH LOOKS TO WORK INTO THE FORECAST AREA THURSDAY
EVENING. NOT MUCH IN THE WAY OF SYNOPTIC LIFT...BUT AS THE COOLER
AIR WORKS INTO THE REGION...COLD AIR COULD PRODUCE ENOUGH LIFT TO
PRODUCE A SMALL AMOUNT OF PRECIPITATION. DEEPER SATURATION APPEARS
TO BE ACROSS THER NORTHERN HALF OF THE FORECAST AREA AND HAVE
CONCENTRATED THE HIGHEST POPS THERE.
ATMOSPHERE DRIES OUT ON FRIDAY WITH NORTHWEST FLOW PREVAILING ACROSS
THE AREA. THE NORTHWEST FLOW WILL KEEP 925 HPA TEMPS AROUND -10C
FRIDAY INTO SATURDAY...WHEN A SEOCND PUSH OF ARCITIC AIR WORKS
SOUTH. AS WITH PREVIOUS FORECASTER...RAISED WINDS OVER INITIAL
GUIDANCE DURING THE PUSHES OF ARCTIC AIR TO ACCOUNT FOR MIXING AND
COLD AIR ADVECTION.
COLD AIR LOOKS TO REMAIN IN PLACE TILL EARLY NEXT WEEK. ECMWF IS
MORE AGGRESSIVE IN MOVING THE ARCTIC AIR EAST SUNDAY NIGHT INTO
MONDAY...WHILE THE GFS KEEPS IT AROUND FOR AT LEAST THE FIRST HALF
OF THE WEEK. STARTED TO TREND TEMPS WARMER ON DAYS 5 THROUGH
7...BUT DIDN/T MAKE MAJOR CHANGES COMPARED TO GUIDANCE AS
CLIMATOLOGICAL BIAS. GFS KEEPS ZONAL FLOW THROUGH MUCH OF NEXT
WEEK...WHILE THE ECMWF SUGGEST THE POTENTIAL FOR A MAJOR SOUTHERN
STREAM WAVE WORKING INTO THE CENTER PORTION OF THE COUNTRY LATE NEXT
WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 939 AM CST WED JAN 13 2016
VFR CONDITIONS ARE EXPECTED TO PERSIST INTO THE EVENING HOURS. WE
WILL SEE AN INCREASE IN HIGH AND MID LVL CLOUDS THIS EVENING AS
INITIAL BAND OF WARM ADVECTION AHEAD OF AN UPPER WAVE MOVES
THROUGH.
HOWEVER...MODELS SUGGEST THIS CLOUD COVER SLIDES JUST NORTHEAST OF
THE AREA AFTER MIDNIGHT. WITH A WEAK SFC TROUGH FORMING NEAR OR
OVER THE CWA AND PERSISTENT WARM ADVECTION OVER THE SNOW
PACK...WOULD NOT BE SURPRISED TO SEE FOG AND EVEN DENSE FOG FORM
ALONG A LINE FROM HON TO FSD TO SLB...BUT ESPECIALLY ACROSS SW
MINNESOTA.
SREF HINTING AT HIGH PROBABILITIES OF VISIBILITIES LESS THAN 1
MILE...AND THIS IS ALSO SUPPORTED BY THE RAP AND HRRR. WILL
INTRODUCE FOG THROUGH THURSDAY MORNING...BUT WITH UNCERTAINTY WILL
KEEP VISIBILITIES AT HIGHER LEVELS AND LET FOLLOWING SHIFTS ADJUST
LOWER AS NEEDED.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
SHORT TERM...DUX
LONG TERM...
AVIATION...DUX
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
1047 AM CST WED JAN 13 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 300 AM CST WED JAN 13 2016
TEMPERATURES WILL BE THE PRIMARY FOCUS FOR THE NEXT 24 HOURS...AS
RELATIVELY BRIEF WARM SURGE CONTINUES TO BUILD INTO THE FORECAST
AREA AHEAD OF LATE WEEK CLIPPER. EARLY MORNING TEMPERATURES ALREADY
5-10 DEGREES WARMER THAN READINGS 24 HOURS AGO...AND THAT 24-HOUR
CHANGE WILL ONLY GROW AS WE PROGRESS THROUGH THE DAY...AS READINGS
CLIMB TOWARD HIGHS IN THE UPPER 20S AND 30S. WIDE VARIANCE BETWEEN
VERY MILD NUMERICAL MOS GUIDANCE AND MUCH COOLER RAW MODEL VALUES...
MAKING IT A TOUGH CALL ON JUST HOW WARM WE WILL GET WITH WIDESPREAD
SNOW COVER. EXPECT A FAIR AMOUNT OF SUNSHINE...AND WITH SNOWPACK NOW
GETTING TO BE ON THE OLDER SIDE FOR MOST...SHOULD SEE ABILITY FOR
DECENT WARMING. FOR NOW HEDGED JUST A LITTLE WARMER THAN PREVIOUS
FORECAST GIVEN RELATIVELY MILD START TO THE DAY AND 30S ALREADY ON
OUR DOORSTEP IN GREGORY COUNTY AND POINTS WEST/SOUTH.
WINDS FAIRLY LIGHT TONIGHT AS THEY BECOME A LITTLE MORE SOUTHERLY...
BUT INCREASE IN CLOUDS THIS EVENING SHOULD TEMPER ANY POTENTIAL FOR
A RAPID FALL AS THE WINDS DIMINISH. THUS EXPECT A MILD NIGHT WITH
LOWS IN THE UPPER TEENS TO MID 20S. WITH SOME AREAS WARMING ABOVE
FREEZING TODAY...AND LIGHT WINDS TONIGHT...GAVE SOME THOUGHT TO
POTENTIAL FOR PATCHY/SHALLOW FOG. SOME OF THE COOLER MODELS DO SHOW
THIS...HOWEVER CONFIDENCE IN THOSE MODELS GENERALLY LOW AS THEY HAVE
TO TENDENCY TO OVERDO LOW CLOUDS/FOG DEVELOPMENT. SO WITHOUT BROADER
MODEL CONSENSUS WILL NOT INCLUDE AT THIS TIME.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 300 AM CST WED JAN 13 2016
THURSDAY STILL LOOKS MILD AS LOW PRESSURE MOVES FROM SOUTH CENTRAL
ND TO SOUTH CENTRAL MN THROUGH THE DAY. 925MB TEMPERATURES RANGE
FROM ABOUT -2C NEAR MARSHALL MN...TO +2C IN OUR FAR SOUTHWEST CORNER
AT GREGORY COUNTY ON BOTH THE GFS AND ECMWF. THEREFORE HIGHS RANGING
FROM THE UPPER 20S IN SOUTHWEST MN TO LOWER 40S IN GREGORY COUNTY
STILL LOOK VERY REASONABLE. THEN THURSDAY NIGHT...THE BOTTOM BEGINS
TO DROP OUT OF OUR TEMPERATURES AS THE FIRST COLD FRONT MOVES
SOUTHWARD. RELIED HEAVILY ON A BLEND OF BIAS CORRECTED AND ECMWF
VALUES WHICH WERE A BIT COOLER THEN CONVENTIONAL BLENDED VALUES. THE
MOISTURE DEPTH IS FAIRLY DEEP THURSDAY NIGHT WHICH SHOULD GIVE AREAS
OF LIGHT SNOW OR FLURRIES. BUT WITH TEMPERATURES SUBSTANTIALLY
WARMER AT 850MB WHEN COMPARED TO 925MB...INSTABILITY IS LACKING
REALLY ALL THE WAY THROUGH 600MB...SO NOT EXPECTING MUCH IN THE WAY
OF ACCUMULATING SNOW. FOR TEMPERATURES...LOWS ARE TRICKY THURSDAY
NIGHT BECAUSE TEMPERATURES WILL LIKELY CONTINUE TO FALL THROUGH
FRIDAY MORNING. FOR NOW...HAVE CLOSE TO 10 DEGREES FOR A LOW NEAR
HURON AND BROOKINGS...SLOWLY WARMING TO AROUND 20 NEAR SIOUX CITY.
ON FRIDAY...MOISTURE DEPTH BEGINS TO SHALLOW OUT SO CONDITIONS
SHOULD BE DRY. AS ELUDED TO ABOVE...TEMPERATURES WILL NOT RECOVER
MUCH AT ALL...PERHAPS JUST A CATEGORY OR TWO IN THE EARLY AND MID
AFTERNOON WHEN COLD AIR ADVECTION TEMPORARILY SUBSIDES. SIMILAR TO
THURSDAY...USED ECMWF AND BIAS CORRECTED VALUES FOR HIGHS. THE NEXT
COLD FRONT AND ACCOMPANYING SHORT WAVE DROPS SOUTHWARD FRIDAY
NIGHT...THIS TIME WITH ARCTIC ORIGINS. SIMILAR TO THURSDAY
NIGHT...THE MOISTURE DEPTH INCREASES ONCE AGAIN AND THIS TIME THE
PROFILE IS PRETTY DENDRITIC FROM THE SURFACE TO 600MB. THEREFORE
FAIRLY CERTAIN THAT FLURRIES WILL OCCUR FOR MOST LOCATIONS AND
INCLUDED THEM IN THE FORECAST. WITH STRONG COLD AIR ADVECTION IN
PLACE...INCREASED WINDS ABOVE SUPERBLEND VALUES GIVING WIND CHILL
VALUES WHICH COULD REACH ADVISORY CRITERIA ROUGHLY ALONG AND EAST OF
A BROOKINGS TO SPENCER IA LINE BY LATE FRIDAY NIGHT OF -20F OR
COLDER.
TEMPERATURES WILL HAVE A VERY SMALL RISE ON SATURDAY AND COUPLED
WITH WIND...THE SAME LOCATIONS MENTIONED ABOVE COULD SEE WIND CHILL
ADVISORY CONDITIONS LINGERING THROUGH THE DAY. THOUGHT ABOUT KEEPING
FLURRIES IN...BUT THE DAY PERIOD ON SATURDAY CURRENTLY HAS THE
MOISTURE DEPTH GETTING SHALLOW AGAIN AND WITH TEMPERATURES GETTING
SUBSTANTIALLY COLDER THEN DENDRITIC. SO WOULD NOT RULE OUT FLURRIES
ON SATURDAY...BUT THEY SHOULD BE PRETTY INSIGNIFICANT. SKIES SHOULD
CLEAR SATURDAY NIGHT ALLOWING TEMPERATURES TO PLUMMET. WITH THE WIND
IN PLACE...THE ENTIRE FORECAST AREA WILL VERY LIKELY SEE WIND CHILL
ADVISORY CONDITIONS WITH POSSIBLY EVEN WIND CHILL WARNING OF -35F
ALONG AND EAST OF A HURON TO SPENCER IA LINE BY LATE SATURDAY NIGHT
AND EARLY SUNDAY MORNING. FRIGID CONDITIONS WILL CONTINUE SUNDAY AND
SUNDAY NIGHT WITH A SLIGHT MODERATION BY MONDAY. HIGHS SHOULD
MODERATE FURTHER ON TUESDAY WITH HIGHS IN THE UPPER TEENS AND 20S
AS SURFACE WINDS BECOME SOUTHERLY AND A ZONAL UPPER FLOW IN PLACE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 939 AM CST WED JAN 13 2016
VFR CONDITIONS ARE EXPECTED TO PERSIST INTO THE EVENING HOURS. WE
WILL SEE AN INCREASE IN HIGH AND MID LVL CLOUDS THIS EVENING AS
INITIAL BAND OF WARM ADVECTION AHEAD OF AN UPPER WAVE MOVES
THROUGH.
HOWEVER...MODELS SUGGEST THIS CLOUD COVER SLIDES JUST NORTHEAST OF
THE AREA AFTER MIDNIGHT. WITH A WEAK SFC TROUGH FORMING NEAR OR
OVER THE CWA AND PERSISTENT WARM ADVECTION OVER THE SNOW
PACK...WOULD NOT BE SURPRISED TO SEE FOG AND EVEN DENSE FOG FORM
ALONG A LINE FROM HON TO FSD TO SLB...BUT ESPECIALLY ACROSS SW
MINNESOTA.
SREF HINTING AT HIGH PROBABILITIES OF VISIBILITIES LESS THAN 1
MILE...AND THIS IS ALSO SUPPORTED BY THE RAP AND HRRR. WILL
INTRODUCE FOG THROUGH THURSDAY MORNING...BUT WITH UNCERTAINTY WILL
KEEP VISIBILITIES AT HIGHER LEVELS AND LET FOLLOWING SHIFTS ADJUST
LOWER AS NEEDED.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
SHORT TERM...JH
LONG TERM...MJ
AVIATION...DUX
AREA FORECAST DISCUSSION
NWS MORRISTOWN TN
247 PM EST WED JAN 13 2016
.SHORT TERM (TONIGHT AND TOMORROW)...
CURRENT WATER VAPOR IMAGERY AND RAP UPPER AIR ANALYSIS INDICATES
RATHER ZONAL FLOW ACROSS THE AREA. AT THE SURFACE...HIGH PRESSURES
IS BEGINNING TO SLIDE TO THE SOUTHEAST. WITH THE MOVEMENT OF THE
SURFACE HIGH...LOW LEVELS WINDS WILL TAKE ON MORE OF A
SOUTHWESTERLY DIRECTION THIS AFTERNOON AND TONIGHT WITH WARM AIR
ADVECTION MOVING INTO THE AREA. THERE IS A WEAK SHORTWAVE TROUGH
MOVING THROUGH THE MID-MISSISSIPPI RIVER VALLEY BUT WITH PW VALUES
SO LOW...DO NOT EXPECT ANYTHING MORE THAN A SLIGHT INCREASE IN
CLOUD COVER LATER THIS EVENING. LOW TEMPERATURES SHOULD BE A GOOD 5
TO 10 DEGREES WARMER THAN LAST NIGHT WITH A LIGHT SOUTHWEST WIND
KEEPING THE BOUNDARY LAYER MIXED AND THE WARM AIR ADVECTION. FOR
TOMORROW...TEMPERATURES AND DEWPOINTS WILL CONTINUE TO INCREASE
WITH LOW LEVEL WARM AIR AND MOISTURE ADVECTON. THE AMPLE SUPPLY ON
SUNSHINE SHOULD ALSO HELP TEMPERATURES TOP OUT IN THE 50S ACROSS
MOST OF THE AREA.
.LONG TERM (THURSDAY NIGHT THROUGH WEDNESDAY)...
MODELS SHOW LIMITED PHASING OF THE NORTHERN AND SOUTHERN STREAM
WAVES FOR FRIDAY...BUT ENOUGH FRONTAL-GENETIC LIFT TO PRODUCE
LIKELY CHANCES OF SHOWERS. SOME LIGHT SNOW SHOWERS/FLURRIES ON THE
BACK SIDE.
BIG DIFFERENCES BETWEEN THE GFS AND ECMWF MODELS FOR THIS WEEKEND.
GFS SUGGEST A GOOD SNOWFALL AREA-WIDE WHILE THE ECMWF KEEPS SOUTHERN
STREAM WAVE IN THE GULF. A WEAK NORTHERN STREAM WAVE DOES EFFECT THE
AREA SUNDAY BRINGING RETURN OF COLD TEMPERATURES AND LIGHT SNOW
SHOWERS/FLURRIES...BUT LIMITED SNOW ACCUMULATIONS.
WILL TREND TOWARD THE ECMWF SINCE ENSEMBLES ARE ALSO TRENDING DRIER
AND COLDER WITH MORE OF A NORTHERN STREAM INFLUENCE.
COLD AND DRY WEATHER FOR THE REST OF THE EXTENDED WITH A GRADUAL
WARMING TREND.
&&
.PRELIMINARY POINT TEMPS/POPS...
CHATTANOOGA AIRPORT, TN 31 57 38 52 / 0 0 20 70
KNOXVILLE MCGHEE TYSON AIRPORT, TN 29 55 34 50 / 0 0 10 60
OAK RIDGE, TN 29 55 35 50 / 0 0 10 60
TRI CITIES AIRPORT, TN 24 52 28 49 / 0 0 0 60
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
MA/DH