Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 01/18/14
AREA FORECAST DISCUSSION
NWS PUEBLO CO
345 AM MST THU JAN 16 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 345 AM MST THU JAN 16 2014
...GUSTY NW WINDS AND BLOWING DUST FAR SE PLAINS TODAY...
CURRENTLY...
OBS AT 2 AM THIS MORNING SHOWED A WIDE SWING IN TEMPS. BANANA BELT
AREAS TO THE LEE OF THE S MTNS WERE LIVING UP TO THEIR REPUTATION AS
TEMPS WERE IN TH 40S. EVEN KPUB...WITH W WINDS AT 10 KNTS...WAS
HOLDING ONTO A 40F TEMP. FURTHER EAST WHERE THE WINDS WERE
LIGHT...TEMPS HAD FALLEN INTO THE U20S/L30S. THE MIDDLE OF THE SAN
LUIS VALLEY (SLV) WERE NEAR ZERO WHILE THE REST OF THE VALLEYS AND
MTNS WERE IN THE TEENS AND 20S.
TODAY...
MAIN CONCERN WILL BE WINDS OVER E PLAINS. MOST AREAS WILL SEE GUSTY
NW WINDS AS 120 KNT JET IMPINGES OVER REGION LATE THIS AFTERNOON.
WINDS AT 700 MBS AT 50 KNTS OVER FAR E PLAINS SO EXPECT WE WILL SEE
A FEW GUSTS TO 50 MPH OVER FAR E PLAINS...ESPECIALLY E KIOWA COUNTY.
BLOWING DUST WILL BE AN ISSUE GENERALLY E OF A LINE FROM KLHX DOWN TO
KSPD.
TEMPS TODAY WILL BE COOLER THAN YDAY...BUT STILL WELL ABOVE NORMAL
FOR THE PLAINS. VARIABLE MID/HI CLOUDINESS WILL MOVE ACROSS THE
PLAINS IN THE STRONG NW FLOW ALOFT.
REST OF AREA WILL SEE MOSTLY SUNNY CONDITIONS. NO PRECIP IS
ANTICIPATE ANYWHERE OVER THE FCST AREA TODAY.
TONIGHT...
WINDS WILL RAPIDLY DECREASE AFTER SUNSET. WITH NO SIGNIFICANT SFC
WESTERLIES OVER THE PLAINS...TEMPS WILL BE MORE UNIFORM (AND
COOL...TEENS) OVER THE LOWER ELEVATIONS. KALS SHOULD GET DOWN INTO
THE NEGATIVE SINGLE DIGITS. /HODANISH
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 345 AM MST THU JAN 16 2014
FRIDAY-SUNDAY...STRONG NORTHERLY FLOW ALOFT ACROSS THE REGION FRIDAY
MODERATES AND BECOMES MORE WEST TO NORTHWEST SATURDAY AND SUNDAY AS
HIGH AMPLITUDE RIDGING ACROSS THE WEST COAST BUILDS EAST ACROSS THE
GREAT BASIN AND INTO THE ROCKIES. PATTERN LOOKS TO KEEP THE AREA DRY
THROUGH THE PERIOD WITH AT AND ABOVE SEASONAL TEMPERATURES ACROSS
THE AREA FRIDAY...WARMING TO WELL ABOVE SEASONAL AVERAGES BY SUNDAY
WITH WARMING ALOFT UNDERNEATH BUILDING RIDGE. THERE WILL STILL BE
BREEZY CONDITIONS OVER AND NEAR THE HIGHER TERRAIN THROUGH THE
PERIOD WITH EXPECTED GOOD MIXING LEADING TO BREEZY AFTERNOON WINDS
ACROSS THE FAR EASTERN PLAINS AS WELL...THOUGH WITH DECREASING WINDS
ALOFT...DOES NOT LOOK TO BE AS STRONG AS PREVIOUS DAYS.
SUNDAY NIGHT-WEDNESDAY...RIDGING ALOFT FLATTENS ACROSS THE AREA
SUNDAY NIGHT WITH INCREASING NORTHWEST FLOW ALOFT AS SHORT WAVE
ENERGY TRANSLATES ACROSS THE NORTHERN ROCKIES AND INTO THE NORTHERN
HIGH PLAINS. PASSING WAVE REMAINS TOO FAR NORTH AND EAST TO PRODUCE
ANY PRECIPITATION BUT LOOKS TO SEND A COLD FRONT ACROSS THE PLAINS
WHICH WILL KNOCK TEMPS BACK SOME 5-15F ACROSS THE AREA ON MONDAY.
LATEST MODELS CONTINUE TO INDICATE UPPER RIDGING REBUILDING ACROSS
THE GREAT BASIN REGION TUESDAY AS AN EASTERN PACIFIC LOW MOVES ON
SHORE ACROSS THE PAC NORTHWEST COAST. MODELS DO DIFFER ON TIMING AND
STRENGTH OF THIS SYSTEM UNDERCUTTING RIDGE AND MOVING ACROSS THE
ROCKIES...WITH THE EC STRONGER AND FASTER MOVING ACROSS THE STATE ON
WEDNESDAY WHEREAS THE GFS IS WEAKER AND MOVES IT ACROSS THE STATE
THURSDAY. WITH CONTINUED DIFFERENCES LIKELY AS MODELS STRUGGLE WITH
ENERGY UNDERCUTTING RIDGE...HAVE KEPT THE AREA DRY THROUGH WEDNESDAY
WITH TEMPERATURES REMAINING AT OR SLIGHTLY ABOVE AVERAGE.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 345 AM MST THU JAN 16 2014
VFR CONDITIONS ANTICIPATED NEXT 24H AT ALL 3 TAF SITES...KPUB...KALS
AND KCOS. WINDS AT KPUB AND KALS WILL BE LIGHT. AT KCOS..WINDS WILL
BE GENERALLY LIGHT BUT DIRECTION MAY BE PROBLEMATIC TODAY. LEADING
EDGE OF NORTHWESTERLY SFC WINDS WILL EXTEND ACROSS EL PASO COUNTY.
HOW FAR WEST THESE NW WINDS MAKE IT BACK TO THE MTNS IS UNCERTAIN.
FOR THIS AFTERNOON...SFC WINDS AT KCOS COULD VARY FROM S TO SW...AND
THEN GO NW FOR AWHILE THIS AFTERNOON...TO EVENTUALLY GOING N THIS
EVENING. WILL CONTINUE TO WATCH TRENDS IN HRRR DATA AND ISSUE
APPROPRIATE FCST AT 1120 UTC.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...HODANISH
LONG TERM...MW
AVIATION...HODANISH
AREA FORECAST DISCUSSION
NWS ALBANY NY
700 PM EST FRI JAN 17 2014
.SYNOPSIS...
A STRONG UPPER LEVEL TROUGH WILL APPROACH THE REGION OVERNIGHT.
THIS WILL PROVIDE THE REGION WITH ANOTHER ROUND OF LIGHT SNOW
DURING THE DAY SATURDAY. ANOTHER DISTURBANCE WILL IMPACT THE
REGION SUNDAY WITH ADDITIONAL SNOW SHOWERS EXPECTED.
THEREAFTER...AN ARCTIC AIR MASS WILL SETTLE ACROSS THE ENTIRE
REGION FOR MOST OF THE UPCOMING WEEK.
&&
.NEAR TERM /THROUGH SATURDAY/...
AS OF 659 PM EST...HIGH CLOUDS WERE SCATTERED AROUND OUR REGION.
MORE SIGNIFICANT CLOUDS AND BANDS OF LIGHT SNOW WERE EVIDENT ACROSS
THE OHIO VALLEY WORKING INTO PA. THIS WILL BE OUR WEATHER
DISTURBANCE THAT COMES THROUGH LATER TOMORROW.
FOR THIS EVENING...IT WILL REMAIN DRY WITH A A PARTLY CLOUDY SKY.
THIS WILL ALLOW FOR SOME RADIATIONAL COOLING...BUT A GENERALLY
THICKENING OF THE HIGHS CLOUDS SHOULD PREVENT A FREE FALL.
TEMPERATURES WILL DIP BELOW FREEZING EVERYWHERE AND IN SOME CASES
WELL DOWN INTO THE 20S...BUT THEN TEMPERATURES WILL LIKELY STALL
OVERNIGHT AS THE CLOUDS THICKEN UP.
H2O VAPOR LOOP ANALYSIS REVEALED A HIGH AMPLITUDE FLOW WITH A RIDGE
OVER WESTERN NOAM...DEEP TROUGH EXTENDING FROM HUDSON BAY INTO THE
GULF OF MEXICO...AND A RIDGE OVER THE CENTRAL ATLANTIC OCEAN. A
CLOSER LOOK SHOWS A RATHER STRONG SHORT WAVE OVER THE OHIO VALLEY
WITH REGIONAL RADARS AT THIS TIME SUGGESTING MAINLY SCATTERED
SHOWERS IN THIS AREA. HOWEVER...ADDITIONAL UPPER SUPPORT WITH A JET
STREAM OVER THE MID ATLANTIC STATES WILL ADD ADDITIONAL SUPPORT FOR
MORE SHOWERS TO DEVELOP THIS EVENING. THESE SHOWERS WILL EVENTUALLY
MIGRATE FROM SOUTH TO NORTH WITH LIFT/OMEGA INCREASING SOUTH OF I90
OVERNIGHT. THEREFORE...WE WILL SHOW A GRADUAL INCREASE IN POPS
TONIGHT ALONG WITH INCREASING CLOUD COVER. AS FOR
TEMPERATURES...WITH AMPLE BREAKS IN THE OVERCAST TODAY AND CLOUDS
EXPECTED TO INCREASE THIS EVENING...WE WILL SHADE TOWARD THE WARMER
SIDE OF THE GUIDANCE WITH LOWS GENERALLY IN THE 20S.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY NIGHT/...
WE BEGIN THIS WEEKEND WITH MAINLY SNOW AS THE AFOREMENTIONED SHORT
WAVE APPROACHES AND MOVES ACROSS THE REGION. THE LATEST RUC13 AND
NCEP MODEL SUITE POINT TOWARD AN ENHANCED BAND OF SNOW LIFTING
FROM SOUTH TO NORTH DURING SATURDAY MORNING PER THE 850-700MB
OMEGA FIELDS. HOWEVER...THE MID LEVEL DRY SLOT ALSO QUICKLY
APPROACHES WHICH SHOULD CUT DOWN ON THE BEST ICE NUCLEI FOR BEST
SNOW FALL RATE POTENTIAL. IN FACT...BUFKIT PROFILES SUGGEST THE
BETTER LIFT WILL OCCUR OUTSIDE OF THE DENDRITIC ZONE SO SNOWFALL
RATES SHOULD REMAIN LOW. DURING THE DAY...THE SNOW WILL BECOME
MORE TERRAIN BASED AS THE UPPER LOW PASSES OVERHEAD AND THE MAIN
SURFACE LOW TRACKS FROM LONG ISLAND AND ACROSS CAPE COD. THE
BETTER DEFORMATION AXIS APPEARS TO REMAIN WEST OF OUR CWFA SO PER
COLLABORATION WITH NEIGHBORING OFFICES...WPC-WWD AND ENSEMBLE
PROBABILITIES...WE WILL WITHHOLD THE MENTION OF HEADLINES AT THIS
TIME AND WORD THE HWO ACCORDINGLY.
LOOK FOR 1-4 INCHES OF SNOWFALL...HIGHEST OVER THE HIGHEST
ELEVATIONS...CLOSER TO AN INCH IN MOST VALLEY LOCATIONS.
THIS SYSTEM WILL QUICKLY DEPART SATURDAY EVENING WITH A NARROW
SHORT WAVE RIDGE AXIS SLIDING OVERHEAD. WHILE MOST OF THE REGION
SHOULD REMAIN RATHER DRY...SOME LAKE EFFECT/ENHANCEMENT DOWNWIND
OF LAKE ONTARIO MAY BRING ADDITIONAL ACCUMULATING SNOWFALL ACROSS
PORTIONS OF THE ADIRONDACKS.
NEXT CLIPPER TYPE SYSTEM APPROACHES FOR SUNDAY WITH AN ADDITIONAL
CHANCE FOR SNOW SHOWERS. THE LAKE WILL CONTINUE TO CONTRIBUTE
ADDITIONAL LOW LEVEL MOISTURE FOR ADDITIONAL SNOWFALL ACROSS
PORTIONS OF THE DACKS BUT INLAND EXTENT AND SHEAR PROFILES SUGGEST
LESS THAN CONFIDENCE TO HOIST ANY HEADLINES AT THIS TIME. IT WILL
BECOME BRISK AS GRADIENT TIGHTENS UP WITH AFTERNOON HIGHS INTO THE
20S AND LOWER 30S.
SUNDAY NIGHT...ARCTIC BOUNDARY APPROACHES WITH ADDITIONAL SNOW
SHOWERS AND POSSIBLE SQUALLS AS LAPSE RATES AT AND BELOW H700
STEEPEN. FURTHERMORE...MIXING LAYER HEIGHTS TOO TAP INTO 30-40KTS
TO MAKE FOR A RATHER BRISK NIGHT. MODEL GUIDANCE ALSO HINTS AT
ANOTHER WAVE DEVELOPING ALONG THE ARCTIC BOUNDARY WHICH COULD
SERVE TO SLOW DOWN THE BOUNDARY ALONG WITH AN INCREASED CHANCE FOR
ACCUMULATING SNOWFALL.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
MUCH OF THE EXTENDED PERIOD WILL BE DOMINATED BY FRIGID...ARCTIC
AIR...WITH LITTLE PRECIPITATION EXPECTED.
AN ARCTIC COLD FRONT WILL PASS THROUGH THE REGION ON MONDAY FROM
NORTHWEST TO SOUTHEAST. SOME SCATTERED SNOW SHOWERS...SNOW
SQUALLS...AND FLURRIES WILL ACCOMPANY THIS BOUNDARY AS IT
CROSSES...ALTHOUGH SNOWFALL WILL BE MINOR DUE TO LIMITED MOISTURE.
MAX TEMPS ON MONDAY WILL RANGE FROM THE TEENS IN THE NW ADIRONDACKS
WHERE THE FRONT WILL BE CROSSING VERY EARLY IN THE DAY TO THE MID TO
UPPER 30S IN THE MID HUDSON VALLEY AND NW CT...WHERE THE FRONT WONT
CROSS TILL LATER IN THE AFTN.
BEHIND THE BOUNDARY...850 HPA TEMPS WILL DROP TO -20 TO -25 DEGREES
C FOR MONDAY NIGHT AND THEY WILL CONTINUE AT THIS LEVEL THROUGH THE
REMAINDER OF THE WEEK. IT WILL BE EXCEPTIONALLY DRY...WITH PWAT
VALUES LESS THAN 0.10 INCHES...WHICH IS WELL BELOW THE
CLIMATOLOGICAL NORMAL VALUES FOR MID TO LATE JANUARY. EXACTLY HOW
COLD IT GETS DURING THIS COLD OUTBREAK WILL DEPEND ON A FEW
FACTORS...SUCH AS HOW CALM THE WINDS CAN GET AT NIGHT AND WHERE
THERE IS FRESH AND DEEP SNOW PACK. FOR NOW...WE WILL FORECAST MAX
TEMPS FOR TUESDAY THROUGH FRIDAY GENERALLY IN THE LOW TO MID TEENS
FOR VALLEY AREAS /SINGLE DIGITS IN THE HIGH TERRAIN/...WITH 0 TO 5
AT NIGHT /BELOW ZERO ACROSS THE HILLS AND MOUNTAINS/. HOWEVER...IT/S
POSSIBLE ITS EVEN COLDER IF IT RADIATES WELL...ESP FOR TUESDAY AND
WED NIGHTS.
LATE IN THE WEEK...THE 12Z ECMWF SHOWS A CLIPPER MOVING ACROSS THE
AREA WITH A REINFORCING SHOT OF COLD AIR FOR THURSDAY NIGHT INTO
FRIDAY...WHICH COULD BRING SOME LIGHT SNOW TO THE REGION. THE ECMWF
HAS BEEN TOO AGGRESSIVE IN DEVELOPING STORMS LATELY...AND WE WILL
FAVOR THE FLATTER AND DRIER 12Z GFS...WHICH FITS WELL WITH THE
LATEST 12Z GEFS. MORE COLD AIR IS SHOWN ON THE MODELS UPSTREAM
ACROSS CENTRAL CANADA...SO IT APPEARS THAT THE BELOW NORMAL TEMPS
WILL CONTINUE INTO NEXT WEEKEND AND FOR THE LATTER PORTION OF THE
MONTH AS WELL.
&&
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
MAINLY VFR FLYING CONDITIONS WILL PREVAIL AT THE TAF SITES THROUGH
EVENING. HOWEVER...WITH AN INITIALLY A MAIN CLEAR SKY...THREW A
TEMPO FOR IFR FOG AT KGFL FROM 03Z-06Z AS CONFIDENCE WAS RIGHT
AROUND 50 PERCENT.
WE DO NOT EXPECT ANY REAL FOG AT THE OTHER SITES...BUT WILL CONTINUE
TO MONITOR.
OVERNIGHT INTO SATURDAY...AN UPPER-LEVEL DISTURBANCE WILL APPROACH
FROM THE GREAT LAKES REGION HELPING TO DEVELOP A WEAK AREA OF LOW
PRESSURE AT THE SURFACE. CLOUDS WILL THICKEN WHICH SHOULD END ANY
RADIATIONAL FOG THREATS EVEN AT KGFL AFTER 06Z.
SCATTERED LIGHT SNOW (VCSH) WILL BEGIN TO OVERSPREAD THE TAF SITES
FROM SOUTH TO NORTH AFTER 06Z...AND BECOME SOMEWHAT STEADIER AROUND
OR RIGHT AFTER THE MORNING PEAK (12Z). WE TAKE CONDITIONS TO
CATEGORICAL IFR (VSBY) AT KGFL...INTRODUCE A 30 PROB AT KALB AND
KPSF...TAKING KPOU ONLY DOWN TO MVFR...BUT POSSIBLY REQUIRING EXTRA
FUEL (PROB30).
THE WIND WILL BE LIGHT AND VARIABLE TONIGHT BEFORE BECOMING LIGHT
NORTHEASTERLY UNDER 10KTS SATURDAY.
OUTLOOK...
SATURDAY: HIGH OPERATIONAL IMPACT. LIKELY SN.
SATURDAY NIGHT: LOW OPERATIONAL IMPACT. BREEZY. SLIGHT CHANCE OF
SHSN.
SUNDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHSN.
SUNDAY NIGHT: LOW OPERATIONAL IMPACT. BREEZY. SLIGHT CHANCE OF SHSN.
MARTIN LUTHER KING JR DAY: MODERATE OPERATIONAL IMPACT. CHANCE OF
SHSN.
MONDAY NIGHT THROUGH WEDNESDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
RIVER AND STREAM LEVELS CONTINUE TO EXHIBIT A SLOW DECLINE FROM
THE RECENT RAINFALL AND SNOW MELT. THROUGH EARLY NEXT WEEK...ONLY
LIGHT PRECIPITATION IN THE FORM OF SNOW IS EXPECTED ACROSS OUR
AREA. THIS PRECIP WILL HAVE LITTLE EFFECT ON AREA RIVERS AND
STREAMS. AS A RESULT...STREAM FLOWS SHOULD GRADUALLY LOWER. COLD
TEMPERATURES RETURNING LATER THIS WEEKEND AND ESPECIALLY NEXT
WEEK...RIVER AND LAKE ICE WILL BEGIN TO REFORM AND STRENGTHEN ONCE
AGAIN.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...BGM
NEAR TERM...HWJIV/BGM
SHORT TERM...BGM
LONG TERM...FRUGIS
AVIATION...HWJIV
HYDROLOGY...BGM
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
343 PM EST THU JAN 16 2014
.DISCUSSION...
TONIGHT...MOSTLY CLEAR TO CLEAR SKIES WILL ALLOW WHAT DAYTIME
HEATING THAT OCCURRED TO QUICKLY RADIATE UPWARD DURING THE EVENING.
TEMPERATURES FALL SHARPLY DURING THE EVENING AND CONTINUE TO DROP
OVERNIGHT AS COLD AIR ADVECTION DURING THE DAY AND OVERNIGHT PUSH
TEMPERATURES THROUGH THE 40S AND INTO THE 30S AROUND MIDNIGHT. NEAR
FREEZING TO FREEZING TEMPERATURES ARE FORECAST INLAND FROM THE
COAST AND OUTSIDE HEAVILY URBANIZED AREAS (I.E. ORLANDO). THE COLDEST
TEMPERATURES ARE EXPECTED TO BE NORTH AND WEST OF INTERSTATE 4 AND
THE SOUTHERN OSCEOLA/OKEECHOBEE COUNTIES WHERE SOME UPPER 20S ARE
POSSIBLE.
FRI...A CHILLY/COLD START TO THE DAY. TEMPERATURES IN THE LOW TO MID
30S MANY LOCATIONS WEST OF INTERSTATE 95 WILL EXPERIENCE A RISE
THROUGH THE UPPER 30S AND INTO THE 40S MID MORNING. WITH THE SURFACE
RIDGE AXIS OVER CENTRAL FLORIDA WINDS SHOULD FROM THE NORTH TO
NORTHWEST AND LIGHT MOST OF THE DAY. CLEAR SKIES...FULL SUN AND
LIGHT WINDS WILL ALLOW TEMPERATURES TO REACH THE LOW AND MID 60S IN
THE AFTERNOON.
SAT-SUN...SURFACE HIGH PRESSURE WILL TAKE UP RESIDENCY OVER MUCH OF
THE GOMEX AND FLORIDA PENINSULA THIS WEEKEND. UPPER TROUGHING
INITIALLY OVER THE EASTERN CONUS EARLY IN THE PERIOD WILL FLATTEN
OUT A BIT BY SUN WITH ZONAL FLOW ALOFT THROUGH MUCH OF THIS TIME.
CONDITIONS WILL REMAIN DRY WITH A CONTINUED WESTERLY COMPONENT OF
WIND NEAR THE SURFACE.
COOL AFTERNOON HIGHS ON SAT...MAINLY IN THE 50S...EXCEPT LOWER 60S
OKEECHOBEE COUNTY AND THE TREASURE COAST. A WARM-UP EXPECTED FOR SUN
WITH HIGHS EXPECTED IN THE MIDDLE TO UPPER 60S AREAWIDE. WITH A HIGH
PRESSURE CENTER FORECAST ACROSS THE SOUTHERN HALF OF FLORIDA SAT
OVERNIGHT COOLER TEMPERATURES WILL CONTINUE WITH LOWS IN THE LOWER
TO MIDDLE 30S SOUTH OF KMCO-KMLB. MIDDLE TO UPPER 30S FORECAST NORTH
OF HERE SAT OVERNIGHT. TEMPERATURES MAINLY IN THE 40S ACROSS MOST OF
THE AREA SUN OVERNIGHT INTO MON MORNING.
MON-WED...ZONAL FLOW ALOFT CONTINUES ACROSS THE DEEP SOUTH AS THE
MIDWEST AND EASTERN SEABOARD NORTH OF FLORIDA DEAL WITH A CONTINUED
UPPER TROUGHING PATTERN THAT DROPS DOWN FROM THE NORTH. AT THE
SURFACE...HIGH PRESSURE BREAKS DOWN THROUGH EARLY TUE AND ANOTHER
SURFACE FRONT PRESSES THROUGH EAST CENTRAL FLORIDA LATE TUE. HAVE
OPTED TO KEEP THE EXTENDED DRY FOR NOW...THOUGH A SMALL POP MAY BE
INTRODUCED LATER BY FUTURE FORECAST SHIFTS WITH THIS LATEST
FRONT...BUT CONFIDENCE IS CURRENTLY NOT HIGH ENOUGH TO ADD JUST YET
IN THIS COOLER AND DRIER PATTERN.
MON-TUE...TEMPERATURES ARE FORECAST TO BE RIGHT AROUND SEASONAL
VALUES FOR BOTH HIGHS/LOWS WITH WED COMING IN A LITTLE COOLER ONCE
AGAIN FOR HIGHS SURROUNDING THE LATEST FRONTAL PASSAGE.
&&
.AVIATION...
VFR. NORTHWEST WINDS AROUND 15 KNOTS DECREASE TO 10 TO 15 KNOTS LATE
AFTERNOON THEN 5 TO 10 KNOTS AFTER MIDNIGHT.
&&
.MARINE...
TONIGHT...THE LATEST LOCAL WRF AND RUC13 MODELS WERE INDICATING
THAT THE WINDS SHOULD DIMINISH TO 20 KNOTS OR LESS LATE AFTERNOON
THEN CONTINUE TO DIMINISH AS THE SURFACE RIDGE AXIS BUILDS ACROSS
EAST CENTRAL FLORIDA AND ITS COASTAL WATERS. THE SMALL CRAFT
ADVISORY EXPIRE AT 4PM/21Z THEN WILL HEADLINE SMALL CRAFT EXERCISE
CAUTION FOR THE OFFSHORE WATERS.
FRI...HIGH PRESSURE RIDGE AXIS WILL EXTEND E-W ACROSS THE FL
PENINSULA AND ADJACENT ATLC. THIS WILL PRODUCE A NW-N WIND FLOW
AROUND 10 KNOTS. WINDS ARE FORECAST TO BACK TO THE WEST IN THE
AFTN ACROSS THE NORTHERN WATERS AS THE RIDGE AXIS SHIFTS SOUTH
AHEAD OF THE NEXT COLD FRONT.
FRI NIGHT...COLD FRONT WILL PUSH ACROSS THE WATERS WITH STRONG
W/NW WINDS INCREASING 20-25 KNOTS OVERNIGHT BEHIND THE FRONT AND
SEAS BUILDING 7-9 FEET OFFSHORE.
SAT-SAT NIGHT...SURFACE HIGH PRESSURE OVER THE NORTH GULF WILL BUILD
EASTWARD ACROSS THE FL PENINSULA. WNW-NW WINDS WILL SLOWLY DECREASE
DURING THE DAY BECOMING 10-15 KTS LATE IN THE AFTERNOON. HOWEVER...A
TAIL END OF ANOTHER FRONT WILL BRUSH THE NORTHERN WATERS LATE SAT
OVERNIGHT CREATING A TIGHTER PRESSURE GRADIENT ONCE AGAIN WITH WNW
WINDS NORTH OF THE CAPE INCREASING IN UPWARDS OF 15-20 KTS VERY
LATE. SEAS WILL BUILD ON SAT TO 5-7 FT WELL OFFSHORE AND 3-5 FT NEAR
SHORE. SEAS ARE FORECAST TO FALL TO 4-5 FT OFFSHORE AND 3-4 FT NEAR
SHORE SAT NIGHT.
SUN-MON...HIGH PRESSURE CONTINUES OVER THE AREA WITH WINDS STEADILY
DECREASING DURING THE DAY ON SUN AND REMAINING BELOW 15 KTS ON MON
WHILE KEEPING A WESTERLY COMPONENT. SEAS 4-6 FT OFFSHORE/NORTH OF
THE CAPE SUN WILL ALSO STEADILY SUBSIDE INTO EARLY NEXT WEEK.
&&
.FIRE WEATHER...
FRI-MON...RH VALUES FALLING INTO THE 30S MOST AREAS ON FRI...WITH
MODELS SUGGESTING UPPER 20S OVER THE INTERIOR SOUTH OF ORLANDO DOWN
TOWARDS OKEECHOBEE FRI AFTERNOON. ANOTHER COLD FRONT WILL MOVE
THROUGH FRI OVERNIGHT NIGHT WITH DRIER CONDITIONS AGAIN RETURNING
FOR SAT. RH`S FROM NEAR KISSIMMEE NORTHWARD WILL FALL INTO THE 20S
WITH 30S MOST EVERYWHERE ELSE SAT AFTERNOON. FOR NOW...SLIGHTLY
HIGHER RELATIVE HUMIDITY VALUES RETURN FOR SUN-MON. 20 FT/TRANSPORT
WINDS CONTINUE TO BE OUT OF THE WEST OR NORTHWEST.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 32 65 39 54 / 10 10 10 0
MCO 34 65 43 56 / 10 10 10 0
MLB 34 65 44 56 / 10 10 10 0
VRB 35 65 46 59 / 10 10 10 0
LEE 32 64 41 54 / 10 10 10 0
SFB 34 66 42 56 / 10 10 10 0
ORL 35 65 44 55 / 10 10 10 0
FPR 34 65 48 58 / 10 10 10 0
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...FREEZE WARNING FROM 4 AM TO 8 AM EST FRIDAY FOR INDIAN RIVER-
INLAND VOLUSIA-MARTIN-NORTHERN LAKE-OKEECHOBEE-ORANGE-
OSCEOLA-SEMINOLE-SOUTHERN LAKE-ST. LUCIE.
FROST ADVISORY FROM 4 AM TO 8 AM EST FRIDAY FOR COASTAL VOLUSIA-
NORTHERN BREVARD-SOUTHERN BREVARD.
RED FLAG WARNING UNTIL 6 PM EST THIS EVENING FOR ORANGE-SEMINOLE.
AM...NONE.
&&
$$
SHORT TERM...WIMMER
LONG TERM....KELLY
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
950 AM EST THU JAN 16 2014
.DISCUSSION...
...FIRST FREEZE SINCE LAST WINTER TONIGHT MANY AREAS...
...COLDER WEATHER CONTINUES THROUGH LATE WEEK...
CURRENT-THIS AFTERNOON...INFRARED SATELLITE LOOP SHOWS THAT THE
CLOUDS ASSOCIATED WITH THE COLD FRONT THAT PASSED THROUGH CENTRAL
FLORIDA EARLIER THIS MORNING WERE RAPIDLY CLEARING NORTH TO SOUTH.
THE VERTICAL WIND PROFILERS AT THE SPACE CENTER WERE RECORDING NORTH
TO NORTHWEST WINDS AT 20 TO 20 MPH FROM JUST ABOVE THE SURFACE TO
AROUND 3500 FEET. THESE WINDS SHOULD MIX DOWN DURING THE MORNING AND
PRODUCE GUSTY NORTH TO NORTHWEST WINDS. UPSTREAM OBSERVATIONS FROM
NORTH FLORIDA INTO SOUTHERN ALABAMA AND GEORGIA WERE SHOWING
TEMPERATURES IN THE LOW 30S AND DEW POINTS IN THE UPPER 20S. THE
STRONG NORTHWEST WINDS WILL ADVECT THIS AIR MASS INTO CENTRAL
FLORIDA DURING THE DAY AND KEEP TEMPERATURES IN THE 50S WITH SOME
LOWER 60S. THESE TEMPERATURES ARE SEVERAL DEGREES BELOW THEIR
SEASONAL UPPER 60S AND LOWER 70S.
MORNING UPDATE TO REMOVE WIND CHILL ADVISORY HEADLINE AND INTRODUCE
TEMPERATURE AND DEW POINT BEING LOWERED A DEGREE OR TWO.
PREVIOUS ZONE DISCUSSION
TONIGHT LTST AVAILABLE GUIDANCE SUGGESTS A LIGHT FREEZE SOUTH TO
AT LEAST LAKE OKEE WITH MUCH LIGHTER TO NEAR CALM WINDS AND OPTIMAL
RADIATIONAL COOLING. VERY LOW DEWPOINTS WL ALLOW TEMPS TO QUICKLY
FALL WITH DARKNESS. THE FREEZE WARNING IS IN EFFECT FOR MOST OF
THE COUNTIES INLAND FROM THE COAST AND METRO ORLANDO. RURAL AREAS
OF WEST ORANGE AND SEMINOLE COUNTIES WILL LIKELY SEE A FEW
FREEZING TEMPERATURES BY DAYBREAK FRIDAY. SOME HIGHER CLOUDS NORTH
OF I-4 EARLY FRI SHOULD PREVENT FULL COOLDOWN INTO THE UPR 20S.
FRI-FRI NIGHT...A VERY COLD START TO THE DAY WITH LOWER TO MIDDLE
30S AREAWIDE NEAR SUNRISE. A FREEZE WARNING WILL BE IN EFFECT FOR
MUCH OF EAST CENTRAL FLORIDA THROUGH 8AM. WHILE IT WILL BE A SLOW
CLIMB EXPECT AFTERNOON TEMPERATURES TO TOUCH THE MIDDLE 60S IF
ONLY BRIEFLY. A LARGE UPPER TROUGH ENGULFS THE CENTRAL/EASTERN
CONUS EARLY IN THIS PERIOD. THIS TROUGH WILL WEAKEN OVER TIME AND
PUSH YET ANOTHER SURFACE FRONT THROUGH EAST CENTRAL FLORIDA FRI
OVERNIGHT. LIGHT TO CALM WINDS NEAR SUNRISE WILL BECOME WESTERLY
BUT STAY BELOW 10 MPH FOR MUCH OF THE AREA. WILL CONTINUE TO KEEP
PRECIPITATION BELOW MENTIONABLE IN THE FORECAST. SURFACE HIGH
PRESSURE WILL BUILD INTO THE NORTH GULF FRI NIGHT. SOUTHWEST TO
WEST WINDS FRI EVENING WILL BECOME NORTHWEST ONCE AGAIN BEHIND THE
AFOREMENTIONED FRONT WITH SPEEDS INCREASING TO BETWEEN 10 AND 15
MPH LATE OVERNIGHT.
LATEST MOS GUIDANCE FORECAST TEMPERATURES EARLY SATURDAY MORNING A
LITTLE HIGHER WITH READINGS IN THE UPPER 30S TO AROUND 40 DEGREES
NORTH OF THE I-4 CORRIDOR. LOWER TO MIDDLE 40S ARE FORECAST MOST
EVERYWHERE ELSE...EXCEPT AND TREASURE COAST/BARRIER ISLANDS WHERE
UPPER 40S TO LOWER 50S SHOULD PREVAIL.
SAT-SUN...SURFACE HIGH PRESSURE WILL TAKE UP RESIDENCY OVER MUCH OF
THE GOMEX AND FLORIDA PENINSULA THIS WEEKEND. UPPER TROUGHING
INITIALLY OVER THE EASTERN CONUS EARLY IN THE PERIOD WILL FLATTEN
OUT A BIT BY SUN WITH ZONAL FLOW ALOFT THROUGH MUCH OF THIS TIME.
CONDITIONS WILL REMAIN DRY WITH A CONTINUED WESTERLY COMPONENT OF
WIND NEAR THE SURFACE.
COOL AFTERNOON HIGHS ON SAT...MAINLY IN THE 50S...EXCEPT LOWER 60S
OKEECHOBEE COUNTY AND THE TREASURE COAST. A WARM-UP EXPECTED FOR SUN
WITH HIGHS EXPECTED IN THE MIDDLE TO UPPER 60S AREAWIDE. WITH A HIGH
PRESSURE CENTER FORECAST ACROSS THE SOUTHERN HALF OF FLORIDA SAT
OVERNIGHT COOLER TEMPERATURES WILL CONTINUE WITH LOWS IN THE LOWER
TO MIDDLE 30S SOUTH OF KMCO-KMLB. MIDDLE TO UPPER 30S FORECAST NORTH
OF HERE SAT OVERNIGHT. TEMPERATURES MAINLY IN THE 40S ACROSS MOST OF
THE AREA SUN OVERNIGHT INTO MON MORNING.
MON-WED...ZONAL FLOW ALOFT CONTINUES ACROSS THE DEEP SOUTH AS THE
MIDWEST AND EASTERN SEABOARD NORTH OF FLORIDA DEAL WITH A CONTINUED
UPPER TROUGHING PATTERN THAT DROPS DOWN FROM THE NORTH. AT THE
SURFACE...HIGH PRESSURE BREAKS DOWN THROUGH EARLY TUE AND ANOTHER
SURFACE FRONT PRESSES THROUGH EAST CENTRAL FLORIDA LATE TUE. HAVE
OPTED TO KEEP THE EXTENDED DRY FOR NOW...THOUGH A SMALL POP MAY BE
INTRODUCED LATER BY FUTURE FORECAST SHIFTS WITH THIS LATEST
FRONT...BUT CONFIDENCE IS CURRENTLY NOT HIGH ENOUGH TO ADD JUST YET
IN THIS COOLER AND DRIER PATTERN.
MON-TUE TEMPERATURES ARE FORECAST TO BE RIGHT AROUND SEASONAL VALUES
FOR BOTH HIGHS/LOWS WITH WED COMING IN A LITTLE COOLER ONCE AGAIN
FOR HIGHS SURROUNDING THE LATEST FRONTAL PASSAGE.
&&
.AVIATION...
VFR. NORTHWEST TO NORTH WINDS 15 TO 20 KNOTS WITH GUSTS 20 TO 25
KNOTS THROUGH 5 PM.
&&
.MARINE...
CURRENT-THIS AFTERNOON...MOST RECENT BUOY REPORTS SHOWED THE BUOY
42NM EAST OF SAINT AUGUSTINE NORTHWEST AROUND 20 KNOTS WITH GUSTS TO
27 KNOTS AND 7 FOOT SEAS. THE BUOY 20NM EAST OF CAPE CANAVERAL WAS
RECORDING NORTHWEST WINDS AROUND 25 KNOTS WITH GUSTS TO 30 KNOTS
WITH HIGHER GUSTS BEING RECORDED EARLIER. THE TWO SCRIPPS BUOYS 4NM
EAST OF PORT CANAVERAL AND 6NM NORTHEAST OF FORT PIERCE INLET WERE
RECORDING 2 AND 4 FOOT SEAS RESPECTIVELY.
THE LATEST LOCAL WRF AND RUC13 MODELS WERE INDICATING THAT THE WINDS
SHOULD DIMINISH TO 20 KNOTS OR LESS LATE AFTERNOON. THIS IS IN SYNC
WITH THE SMALL CRAFT ADVISORY EXPIRING AT 4PM/21Z BUT WILL KEEP AN
EYE ON THE BUOY OBSERVATIONS FOR ANY TRENDS TO THE CONTRARY.
PREVIOUS MARINE DISCUSSION
TODAY AND TONIGHT...POST FRONTAL GRADIENT WINDS OVER THE ATLC WATERS
WL KEEP SOLID ADVISORY CONDS IN PLACE THROUGH MID AFTERNOON THEN
WINDS BEGIN TO DECREASE LATE THIS AFTN WITH SEAS TO FOLLOW. SHOULD
BE ABLE TO TAPER BACK TO CAUTION OFFSHORE THIS EVENING...WITH
COUNTERING WINDS ALONG GULFSTREAM KEEPING SOME CHOPPY CONDITIONS
NR THE CURRENT AND OFFSHORE.
FRI-FRI NIGHT...ANOTHER FRONTAL PASSAGE EXPECTED FRI OVERNIGHT.
INITIAL WEST TO NORTHWEST WINDS AROUND 10 KTS WILL INCREASE TO 20-25
KTS OFFSHORE/NORTH OF SEBASTIAN INLET LATE OVERNIGHT. SEAS 2-3 FT
WILL INCREASE TO 3-5 FT OFFSHORE LATE AND AROUND 3 FT NEAR SHORE FRI
OVERNIGHT BEHIND THE FRONT.
SAT-SAT NIGHT...SURFACE HIGH PRESSURE OVER THE NORTH GULF WILL BUILD
EASTWARD ACROSS THE FL PENINSULA. WNW-NW WINDS WILL SLOWLY DECREASE
DURING THE DAY BECOMING 10-15 KTS LATE IN THE AFTERNOON. HOWEVER...A
TAIL END OF ANOTHER FRONT WILL BRUSH THE NORTHERN WATERS LATE SAT
OVERNIGHT CREATING A TIGHTER PRESSURE GRADIENT ONCE AGAIN WITH WNW
WINDS NORTH OF THE CAPE INCREASING IN UPWARDS OF 15-20 KTS VERY
LATE. SEAS WILL BUILD ON SAT TO 5-7 FT WELL OFFSHORE AND 3-5 FT NEAR
SHORE. SEAS ARE FORECAST TO FALL TO 4-5 FT OFFSHORE AND 3-4 FT NEAR
SHORE SAT NIGHT.
SUN-MON...HIGH PRESSURE CONTINUES OVER THE AREA WITH WINDS STEADILY
DECREASING DURING THE DAY ON SUN AND REMAINING BELOW 15 KTS ON MON
WHILE KEEPING A WESTERLY COMPONENT. SEAS 4-6 FT OFFSHORE/NORTH OF
THE CAPE SUN WILL ALSO STEADILY SUBSIDE INTO EARLY NEXT WEEK.
&&
.FIRE WEATHER...
COLD DRY AIR MASS ADVECTING INTO EAST CENTRAL FLORIDA...ESPECIALLY
THE WESTERN HALF WILL RESULT IN AFTERNOON RELATIVE HUMIDITY VALUES
LESS THAN 35 PERCENT.
THE RED FLAG WARNING FOR ORANGE AND SEMINOLE COUNTIES REMAINS IN
EFFECT UNTIL 6 PM THIS AFTERNOON. THE REST OF EAST CENTRAL FLORIDA
WILL EXPERIENCE SEVERAL HOURS OF RELATIVE HUMIDITY VALUES BELOW 40
PERCENT. THE COMBINATION OF THE RELATIVE HUMIDITY APPROACHING THE
CRITICAL THRESHOLD 35 PERCENT...BRISK NORTHWEST WINDS JUST UNDER 15
MPH AND DRYING SMALL FUELS WILL MAKE FOR A FIRE SENSITIVE DAY FOR
MOST OF EAST CENTRAL FLORIDA.
PREVIOUS FIRE WEATHER DISCUSSION
QUITE COOL CONDITIONS BEHIND THE MORNING FRONTAL PASSAGE WILL
OCCUR...HOWEVER VERY LOW RH WILL STILL DEVELOP OVER NORTH AND
CENTRAL DUE A MUCH DRIER AIRMASS THIS AFTERNOON. EXPECT NORTHWEST
WINDS GUSTY AT TIMES. REPORTED ERCS IN PORTIONS OF THE ORLANDO
DISTRICT NEAR 30 REQUIRED THE RED FLAG WARNING WHEN COMBINED WITH
MIN RH AND WINDS FORECAST.
FRI-MON...RH VALUES FALLING INTO THE 30S MOST AREAS ON FRI...WITH
MODELS SUGGESTING UPPER 20S OVER THE INTERIOR SOUTH OF ORLANDO DOWN
TOWARDS OKEECHOBEE FRI AFTERNOON. ANOTHER COLD FRONT WILL MOVE
THROUGH FRI OVERNIGHT NIGHT WITH DRIER CONDITIONS AGAIN RETURNING
FOR SAT. RH`S FROM NEAR KISSIMMEE NORTHWARD WILL FALL INTO THE 20S
WITH 30S MOST EVERYWHERE ELSE SAT AFTERNOON. FOR NOW...SLIGHTLY
HIGHER RELATIVE HUMIDITY VALUES RETURN FOR SUN-MON. 20 FT/TRANSPORT
WINDS CONTINUE TO BE OUT OF THE WEST OR NORTHWEST.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 56 35 65 41 / 0 0 10 10
MCO 58 35 64 45 / 0 0 10 10
MLB 60 36 66 46 / 0 0 10 10
VRB 59 34 66 50 / 0 0 10 10
LEE 56 31 65 42 / 0 0 10 10
SFB 57 35 65 43 / 0 0 10 10
ORL 56 36 64 46 / 0 0 10 10
FPR 59 33 65 49 / 0 0 10 10
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...FREEZE WARNING FROM 1 AM TO 8 AM EST FRIDAY FOR INDIAN RIVER-
INLAND VOLUSIA-MARTIN-NORTHERN LAKE-OKEECHOBEE-OSCEOLA-
SOUTHERN LAKE-ST. LUCIE.
WIND CHILL ADVISORY UNTIL 9 AM EST THIS MORNING FOR COASTAL
VOLUSIA-INLAND VOLUSIA-NORTHERN LAKE-SOUTHERN LAKE.
RED FLAG WARNING FROM 11 AM THIS MORNING TO 6 PM EST THIS
EVENING FOR ORANGE-SEMINOLE.
AM...SMALL CRAFT ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR COASTAL
WATERS FROM FLAGLER BEACH TO VOLUSIA BREVARD COUNTY LINE
OUT 20 NM-COASTAL WATERS FROM SEBASTIAN INLET TO JUPITER
INLET OUT 20 NM-COASTAL WATERS FROM VOLUSIA BREVARD COUNTY
LINE TO SEBASTIAN INLET OUT 20 NM-WATERS FROM FLAGLER BEACH
TO VOLUSIA BREVARD COUNTY LINE 20 TO 60 NM OFFSHORE-WATERS
FROM SEBASTIAN INLET TO JUPITER INLET 20 TO 60 NM OFFSHORE-
WATERS FROM VOLUSIA BREVARD COUNTY LINE TO SEBASTIAN INLET
20 TO 60 NM OFFSHORE.
&&
$$
FORECASTS...WIMMER
IMPACT WX...KELLY
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
358 AM EST THU JAN 16 2014
.SYNOPSIS...
HIGH PRESSURE WILL BRIEFLY BUILD TODAY...FOLLOWED BY ANOTHER COLD
FRONT LATE FRIDAY. HIGH PRESSURE WILL THEN QUICKLY RETURN FOR
SATURDAY...WHILE YET ANOTHER COLD FRONT COULD PASS THROUGH THE
REGION LATE IN THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
PRE-DAWN...A HIGHLY AMPLIFIED AND DEEP LAYERED MID/UPPER TROUGH AXIS
POISED TO SWING THROUGH THE FORECAST AREA DURING THE NEXT 2-4 HOURS
WITH IMPRESSIVE PVA NOTED ON THE LATEST RUC40 300MB-700MB 2 HOUR
PROG AT 08Z THIS MORNING. WEAK CYCLOGENESIS ONGOING OVER THE GULF
STREAM EAST OF CHARLESTON ALONG THE FRONT WITH BACK EDGE OF THE
CLEARING LINE MOVING IN ON THE I-95 CORRIDOR. RADAR INDICATES AREAS
OF LIGHT RAIN FROM THE GEORGIA COASTAL WATERS TO THE CHARLESTON TRI-
COUNTY AREA WITH THE BAND SLIPPING OFF TO THE EAST WITH TIME.
TEMPS HAVE BEEN SLOW TO COOL UNDER THE CLOUD SHIELD BISECTING THE
FORECAST AREA...FALLING OFF INTO THE MID 30S UNDER THE SCATTERED
CLOUDS/CLEAR SKIES TO THE W OF SAVANNAH. LATEST RAP FORECAST
SOUNDINGS INDICATE THE LIGHT PRECIP SHOULD CONTINUE TO BE LIQUID
AS IT MOVES OUT. MEASURABLE RAIN POTENTIAL IN THE SLIGHT CHANCE
RANGE FOR 2-3 MORE HOURS ACROSS THE CHARLESTON TRI-COUNTY AREA.
THE UPPER TROUGH AND WEAK COASTAL LOW WILL SCOOT QUICKLY AWAY AFTER
DAWN WITH MID LEVEL FLOW GOING ZONAL RAPIDLY BY 18Z AS A SHORT WAVE
RIDGE SQUEEZES UNDER THE NEXT UPPER DISTURBANCE APPROACHING FROM
THE CENTRAL PLAINS. SUNSHINE WILL BE THE RULE AFTER THE EXODUS OF
THE EARLY MORNING SYSTEM AS STRONG UPPER SUBSIDENCE BUILDS THROUGH
A DRY DEEP LAYERED ATMOSPHERE. LOW LEVEL THICKNESS CONTINUES TO
SUGGEST HIGHS MANY AREAS WILL STRUGGLE TO REACH 50 TODAY BUT OF
NOTE WAS NAM/ECMWF GUIDANCE COMING IN 2-3 DEGREES WARMER THAN
PREVIOUS RUNS GIVEN THE DOWNSLOPE AND QUICKLY RISING HEIGHTS. WE
BUMPED OUR MAX TEMPS UP A DEGREE OR SO IN SOME AREAS BUT MAINTAINED
SIMILAR TRENDS TOWARD A MUCH COOLER DAY THE LOW TO MID 60S SEEN ON
WEDNESDAY.
TRICKY TEMP FORECAST TONIGHT AS FIRST GLANCE HAD US WONDERING IF
OUR LOWS ARE A BIT TOO WARM GIVEN THE POTENTIAL FOR A DECENT
RADIATIONAL SETUP. LOW LEVEL WINDS ATOP THE BOUNDARY LAYER ARE
FORECAST TO INCREASE A BIT OVERNIGHT BUT SKIES WILL REMAIN CLEAR.
WE ADJUSTED SOME NORMALLY COOLER LOCATIONS DOWN A COUPLE OF
DEGREES TO TREND BUT DID NOT OPT FOR READINGS SEEN IN THE 00Z CO-
OP MOS GUIDANCE WHICH WERE IN THE LOW TO MID 20S AT PLACES SUCH AS
ALLENDALE AND ROCKY FORD.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY/...
FRIDAY...ANOTHER STRONG UPPER SHORTWAVE WILL DIVE THROUGH THE GREAT
LAKES REGION DURING THE DAYTIME HOURS AND AMPLIFY ALONG THE EAST
COAST OVERNIGHT. THE CORRELATED SURFACE LOW OVER THE GREAT LAKES
WILL TRACK EASTWARD AND PULL A COLD FRONT TOWARD THE REGION LATE
IN THE DAY. SOME PRE-FRONTAL COMPRESSION COULD ALLOW AFTERNOON
TEMPERATURES TO MODERATE SLIGHTLY FROM THE PREVIOUS DAY...YET
STILL ONLY PEAK IN THE MID TO UPPER 50S. LITTLE MOISTURE RETURN
AHEAD OF THE APPROACHING FRONT SUGGESTS KEEPING RAIN CHANCES BELOW
15 PERCENT ON FRIDAY...WITH JUST INCREASING SKY COVER ACCOMPANYING
THE SOUTHERN EXTENT OF THE SYSTEM. A STRONG SURGE OF COLD ADVECTION
WILL FOLLOW IN THE WAKE OF THE FRONT THAT WILL BE PASSING OFFSHORE
FROM LATE EVENING THROUGH MIDNIGHT. LOW TEMPERATURES WILL THUS
RANGE FROM THE UPPER 20S INLAND TO THE LOWER 30S ALONG THE COAST.
SATURDAY...SURFACE HIGH PRESSURE WILL ATTEMPT TO REBUILD FROM THE
WEST/SOUTHWEST BEHIND THE DEPARTING COLD FRONT...YET QUICKLY
BECOME SUPPRESSED OVERNIGHT BY ANOTHER CLIPPER TYPE SYSTEM
SWINGING SOUTHEAST FROM THE GREAT LAKES REGION. CONSIDERING A COLD
AIR MASS LINGERING OVER THE AREA...AS WELL AS THE CONSISTENTLY
REINFORCED LONG WAVE TROUGH PATTERN ALOFT...TEMPERATURES ON
SATURDAY COULD BE QUITE COLD. DESPITE MOSTLY CLEAR SKIES...HIGH
TEMPERATURES WILL ONLY REACH THE MID TO UPPER 40S. WHEN ALSO
FACTORING IN THE BREEZY CONDITIONS DURING THE AFTERNOON...WIND
CHILLS COULD BE AS LOW AS THE UPPER 30S. NIGHTTIME LOW
TEMPERATURES WILL GENERALLY RANGE FROM THE LOW TO MID 30S...WITH
SUFFICIENT WIND SPEEDS OVERNIGHT TO SUPPORT WIND CHILLS IN THE
20S.
SUNDAY...THE CENTER OF SURFACE HIGH PRESSURE TO THE SOUTH WILL
HAVE THE OPPORTUNITY TO BUILD INTO THE REGION BY EARLY NEXT WEEK.
THE UPPER LEVEL PATTERN WILL TRANSITION TO PSEUDO-ZONAL...AND WITH
THESE CHANGES AT THE SURFACE AND ALOFT...EXPECT HIGH TEMPERATURES
TO PEAK 10 DEGREES WARMER THAN THE PREVIOUS DAY. HIGH
TEMPERATURES WILL BE IN THE MID TO UPPER 50S UNDER CLEARING
SKIES...WITH RAIN CHANCES AT ZERO.
&&
.LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/...
SURFACE HIGH PRESSURE WILL PERSIST THROUGH MONDAY AFTERNOON...YET
GRADUALLY BECOME SUPPRESSED SOUTH OF A FRONTAL TROUGH LATE MONDAY
INTO TUESDAY. THE BRIEF ZONAL PATTERN ALOFT WILL GRADUALLY
TRANSITION BACK INTO A LONG WAVE TROUGH SETUP. MEDIUM RANGE MODEL
SOLUTIONS DIVERGE A BIT REGARDING THE TIMING OF AN EARLY WEEK
FRONT...INDICATING ITS PROGRESSION THROUGH THE FORECAST AREA
MONDAY NIGHT OR TUESDAY. HAVE ADVERTISED MORE MILD HIGH
TEMPERATURES MONDAY AND TUESDAY IN THE LOWER 60S...BEFORE
INDICATING ANOTHER COOLING TREND FOR THE MIDDLE OF THE WEEK...WITH
TEMPERATURES ONLY PEAKING IN THE UPPER 40S TO LOWER 50S WEDNESDAY
AND THURSDAY. LOW TEMPERATURES COULD BECOME QUITE COLD BEHIND THE
FRONT...FALLING INTO THE 20 DEGREE RANGE WEDNESDAY NIGHT AND
PERHAPS THURSDAY NIGHT. ALTHOUGH THE PATTERN WILL REMAIN SOMEWHAT
DYNAMIC DURING THE EARLY AND MID WEEK PERIOD...MOISTURE
AVAILABILITY WITH ANY FRONTAL SYSTEM REMAINS UNCERTAIN. HAVE THUS
CONTINUED TO CAP RAIN CHANCES BELOW 15 PERCENT THROUGH THE
EXTENDED FORECAST PERIOD.
&&
.AVIATION /09Z THURSDAY THROUGH MONDAY/...
PATCHY LIGHT RAIN SHOULD END AT KCHS BY DAYBREAK. WINDS COULD BE
BRIEFLY GUSTY THIS MORNING BEFORE DIMINISHING THIS AFTERNOON.
OTHERWISE...HIGH CONFIDENCE IN VFR CONDITIONS PREVAILING THROUGH
TONIGHT.
EXTENDED AVIATION OUTLOOK...VFR CONDITIONS WILL GENERALLY PREVAIL.
BREEZY CONDITIONS EXPECTED FRIDAY AND SATURDAY AFTERNOONS.
&&
.MARINE...
ONGOING FORECAST REMAINS ON TRACK THIS MORNING WITH SMALL CRAFT
ADVISORIES ALONG THE EXTREME SOUTHERN CAROLINA COAST AND ALL OF
GEORGIA/S WATERS. ISALLOBARIC PRES RISES HAVE NOT BEEN TOO
IMPRESSIVE TO THIS POINT OFF THE GEORGIA COAST BUT THE NAM PROGS
1 MB/HOUR THROUGH 12Z AND THIS SEEMS REASONABLE GIVEN THE LATEST
ANALYSIS.
STRONGEST FLOW THIS MORNING WILL OCCUR SEAWARD FROM THE SAVANNAH
PILOT BUOY TO GRAYS REEF WITH NW FLOW 20 KT GUST 30 KT AT TIMES.
WINDS AND CHOPPY SEAS FROM WIND WAVE WILL SUBSIDE THIS AFTERNOON
AS THE ADVECTION PATTERN DIMINISHES AND THE GRADIENT WEAKENS IN
THE WAKE OF THE BIG UPPER TROUGH. AN OFFSHORE FLOW TONIGHT MAINLY
IN THE 15 KT RANGE WITH SEAS 2 TO 4 FT...HIGHEST WELL OFFSHORE.
FRIDAY THROUGH MONDAY...A COLD FRONT WILL APPROACH THE MARINE
ZONES ON FRIDAY AND CROSS THE WATERS FRIDAY NIGHT. THE SUBSEQUENT
COLD ADVECTION AND TIGHTENED GRADIENT WILL SUPPORT SMALL CRAFT
ADVISORY CONDITIONS LATE FRIDAY THROUGH AT LEAST SATURDAY
MORNING. SURFACE HIGH PRESSURE WILL BRIEFLY BUILD INTO THE REGION
SATURDAY...BEFORE GIVING WAY TO ANOTHER FRONT SATURDAY NIGHT INTO
EARLY SUNDAY. THUS THE LULL IN ADVISORY CONDITIONS MIDDAY SATURDAY
WILL END BY SATURDAY NIGHT...WITH PORTIONS OF THE WATERS GOING
BACK TOWARD ADVISORY LEVEL WINDS AND SEAS THROUGH SUNDAY.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 AM EST THIS MORNING FOR AMZ352.
SMALL CRAFT ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR AMZ374.
SMALL CRAFT ADVISORY UNTIL 10 AM EST THIS MORNING FOR AMZ354.
&&
$$
SYNOPSIS...
NEAR TERM...
SHORT TERM...WMS
LONG TERM...WMS
AVIATION...
MARINE...WMS
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
904 PM CST FRI JAN 17 2014
.DISCUSSION...
640 PM CST
EARLY EVENING UPDATE...
MINOR CHANGES TO FORECAST GRIDS/ZFP TO RAISE POPS ACROSS NORTHEAST
IL THROUGH EARLY EVENING...AS AREA OF LIGHT SNOW CONTINUES TO PIVOT
SLOWLY SOUTHEAST ACROSS THE REGION.
RECENT AMDAR ASCENT SOUNDING FROM KMDW CONTINUES TO DEPICT SATURATED
COLUMN FROM 900 MB THROUGH AROUND 775 MB...WITH ENTIRE MOIST LAYER
LOCATED WITHIN THE DENDRITIC GROWTH SWEET SPOT -15C TO -17C. WEAK
SHEARED MID-LEVEL VORT MAX ROTATING AROUND BACK SIDE OF LARGER SCALE
UPPER TROUGH AXIS IS PROVIDING WEAK BUT PERSISTENT FORCING
SUFFICIENT TO PRODUCE LIGHT SNOW WITH SOME MINOR ACCUMULATIONS.
TRENDS FROM SHORT TERM RAP GUIDANCE CONTINUES TO WEAKEN AND MOVE THE
VORT AXIS OFF TO THE SOUTHEAST THROUGH MID-EVENING...ALLOWING A
DECREASE IN INTENSITY OF THE LIGHT SNOW TO SCATTERED FLURRIES BY THE
LATE EVENING HOURS. THIS IS PRETTY MUCH IN LINE WITH PREVIOUS
FORECAST TRENDS...THOUGH HAVE INCREASED POPS IN NEXT FEW HOURS TO
CATEGORICAL ACROSS NORTHEAST IL WHERE LIGHT SNOW CURRENTLY PRODUCING
SOME LIGHT ACCUMS. FLUFFY NATURE OF SOME OF THE DENDRITES MAY ALLOW
UP TO A HALF INCH OF ADDITIONAL ACCUMULATION IN SOME SPOTS ACROSS
THE CHICAGO METRO AREA...COINCIDENT WITH SOME OF THE STRONG 20+ DBZ
RADAR RETURNS. DRIER AIR FILTERING IN FROM THE WEST MAY ALLOW SOME
PARTIAL CLEARING ACROSS NORTH CENTRAL IL...BEFORE RAPIDLY ADVANCING
CIRRUS SHIELD SPREADS IN AHEAD OF TOMORROWS CLIPPER.
RATZER
//PREV DISCUSSION...
301 PM CST
REST OF TODAY AND TONIGHT...
AREA OF LIGHT SNOW CONTINUES TO PIVOT ACROSS NORTHERN ILLINOIS THIS
AFTERNOON ASSOCIATED WITH A SHEARED VORT LOBE ROTATING AROUND THE
MAIN UPPER TROUGH AXIS WHICH HAS SHIFTED EAST OF THE AREA.
SMALLER SCALE FORCING IS EMBEDDED WITHIN LARGER SCALE
SUBSIDENCE AS AN H5 RIDGE BUILDS OVER THE AREA OVERNIGHT. UPSTREAM
VSBY GENERALLY IN THE 2-5SM RANGE PERIODICALLY DROPPING
BELOW...INDICATING THAT MOST OF THE SNOW IS PRETTY LIGHT. EXPECT THE
AREA TO CONTINUE TO PIVOT EAST ACROSS NORTHERN ILLINOIS POSSIBLY
DROPPING A DUSTING OF SNOW WITH FLURRIES LINGERING INTO THE
EVENING.
SATURDAY...
ANOTHER ROUND OF SNOW IS EXPECTED ON SATURDAY WITH MODEST
ACCUMULATION APPEARING LIKELY. A 130KT JET DIGGING INTO THE UPPER
MIDWEST WITH A POTENT H5 VORT MAX AT THE NOSE OF THE JET WILL RACE
SOUTHEAST ACROSS IOWA INTO CENTRAL ILLINOIS SATURDAY AFTERNOON.
TAKING A LOOK FOR THE HOOK ON THE PV1.5 SURFACE...A TROP FOLD
EXTENDS DOWN TO ALMOST 600 MB SATURDAY AFTERNOON...WITH THE BEST
PRESSURE ADVECTION AND ASCENT FOCUSED ACROSS CENTRAL ILLINOIS
INCLUDING PORTIONS OF THE FAR SOUTHERN CWA WHERE THE SURFACE LOW IS
EXPECTED TO TRACK. ISENTROPIC SURFACES SIMILARLY INDICATE TIGHTEST
PACKING IN THE FAR WEST/SOUTH CWA WITH THE BEST FOCUSED ASCENT
AND RESULTING PRECIP AXIS EXTENDING FROM ROUGHLY DIXON ILLINOIS TO
FOWLER INDIANA. IN ADDITION...CROSS SECTIONS SHOW AN AREA OF
STRONGER F-GEN TRANSLATING ALONG THAT SAME LINE WITH NEGATIVE
SATURATED EPV RIGHT ON TOP OF THE LAYER OF BEST F-GEN...INDICATING
THE POTENTIAL FOR A DEEP VERTICAL RESPONSE AND BANDED SNOWFALL WITH
UNEVEN DISTRIBUTION OF THE SNOW TOTALS. UTILIZED A NAM/GFS QPF
BLEND FOR THIS PERIOD...AND SLIGHTLY HIGHER THAN AVERAGE SNOW RATIOS
AROUND 15-16:1...CAME UP WITH 3 TO 5 INCHES ALONG AND SOUTH OF THE
DIXON TO FOWLER LINE...WITH 1 TO 3 INCHES TO THE NORTH. THESE
AMOUNTS LINE UP WELL WITH GARCIA METHOD WHICH RESULTS IN ROUGHLY 3-4
INCHES...AND SREF PLUMES. AGAIN...WITH THE POTENTIAL FOR MESOSCALE
BANDING...THERE COULD BE SOME LOCALIZED HIGHER AMOUNTS OF 5 TO 6
INCHES WITHIN THE MAIN PRECIP AXIS ACROSS THE WEST/SOUTH PORTION OF
THE CWA. WILL GO AHEAD AND ISSUE A WINTER WEATHER ADVISORY FOR 3 TO
5 INCHES OF SNOW FOR THE AFFECTED AREAS.
SUNDAY AND MONDAY...
ON SUNDAY BROAD H5 HEIGHT RISES WILL BUILD ACROSS THE AREA WITH
TRANSIENT SURFACE RIDGE PROGRESSING ACROSS THE AREA EARLY IN THE
DAY. WINDS BACK TO THE SOUTHWEST BY SUNDAY AFTERNOON WITH H85
THERMAL GRADIENT LIFTING ACROSS THE AREA...WITH TEMPS APPROACHING
3-4C. SURFACE TEMPS SHOULD PUSH TO OR SLIGHTLY ABOVE THE FREEZING
MARK...TEMPERED SOME BY SATURDAYS SNOWPACK. ANOTHER SHORTWAVE WILL
BRUSH JUST NORTH OF THE AREA SUNDAY NIGHT WITH A COLD FRONT PUSHING
SOUTH ACROSS THE AREA THROUGH THE DAY MONDAY. MOISTURE SOMEWHAT
SHALLOW BEHIND THE FRONT...BUT STEEP LOW LEVEL LAPSE RATES WITH EVEN
SOME UPRIGHT INSTABILITY NOTED ON THE SOUNDINGS INDICATE THE
POTENTIAL FOR AT LEAST SOME FLURRIES IF NOT A FEW SNOW SHOWERS.
DEPENDING ON THE EXACT TIMING OF THE FRONT...COULD SEE TEMPS FALLING
THROUGH THE DAY MONDAY. TAKING A STEP BACK AND LOOKING AT THE BIGGER
PICTURE FOR MONDAY...STRONG RIDGING OVER THE WEST COAST AND ALASKA
THIS WEEKEND WILL HELP DISLODGE AN ARCTIC AIRMASS WHICH WILL SINK
INTO GREAT LAKES MONDAY WITH THE LEADING EDGE REACHING NEAR THE OHIO
VALLEY BY MONDAY EVENING. THE COLDEST AIR AROUND -30C WILL STAY
PRIMARILY OVER THE NORTHERN LAKES REGION BUT MODELS CONTINUE TO SHOW
-20C AIR REACHING INTO ILLINOIS RESULTING IN ANOTHER PERIOD OF
FRIGID CONDITIONS AS WE HEAD INTO NEXT WEEK.
DEUBELBEISS
LONG TERM...MONDAY NIGHT THROUGH THURSDAY...
THE UPPER LEVEL TROUGH REMAINS OVERHEAD WITH SUBSEQUENT TROUGH
AXES PASS OVER THE REGION MONDAY NIGHT AND MID TO LATE NEXT WEEK.
AT THE SURFACE...HIGH PRESSURE BUILDS OVER THE GREAT PLAINS AND
MIDWEST MONDAY NIGHT THROUGH TUESDAY NIGHT. LOW PRESSURE PASSES TO
THE NORTH MID WEEK WITH HIGH PRESSURE BUILDING IN BEHIND IT.
GIVEN THE MODEL DISCREPANCIES REGARDING WHEN THE UPPER LEVEL TROUGH
AXIS/SURFACE LOW WILL PASS THROUGH THE REGION...KEPT POPS IN THE
SLIGHT CHANCE TO CHANCE RANGE MID TO LATE NEXT WEEK. THE ECMWF IS
FASTER AND FEATURES A MUCH STRONGER LOW...BUT WILL RESIST LEANING
TOO MUCH IN ITS DIRECTION.
FOR TEMPS...COLD AIR MOVES IN MONDAY NIGHT WITH 925MB TEMPS FALLING
TO -16 TO -22C. LOWERED MONDAY NIGHT/S LOWS A BIT...BUT ONCE AGAIN
WAITING FOR MODELS TO COME INTO BETTER ALIGNMENT BEFORE MAKING MAJOR
CHANGES. TUESDAY NIGHT LOOKS TO BE THE COLDEST WITH CONTINUED COLD
AIR UPSTAIRS AND A SURFACE HIGH OVERHEAD. LOWS BTWN 0 AND -10F IF
NOT COLDER ARE EXPECTED. BRIEF WAA ON WEDNESDAY WILL LEAD TO HIGH
TEMPS ABOVE 0. TEMPS AROUND ZERO ARE EXPECTED AGAIN WEDNESDAY NIGHT
WITH BELOW NORMAL TEMPS CONTINUING THROUGH LATE NEXT WEEK.
JEE
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 03Z...
* AREAS OF FLURRIES WITH PATCHY MVFR CIGS THROUGH 06Z OR SO.
* ACCUMULATING SNOW WITH IFR CONDITIONS BEGINNING MID AFTERNOON
SAT AND PERSISTING INTO EARLY SAT EVE.
* SOUTHEAST TO EAST WINDS AROUND 10 KT BY MID SAT AFTERNOON INTO
EARLY SAT EVE...BECOMING NORTHWEST BY MID EVE.
//DISCUSSION...UPDATED 00Z...
LOW PRESSURE CONTINUES TO PULL AWAY FROM THE EASTERN GREAT LAKES
REGION WITH UPPER LEVEL FORCING CONTINUING TO SUPPORT SNOW EARLY
THIS EVE. AS THIS FORCING SLOWLY FADES THE SNOW WILL FOLLOW
SUIT...TAPERING TO FLURRIES. CIGS BELOW 2000 FT HAVE BEEN VERY
PATCHY AND THAT LIKELY HAS TO DO WITH DRY SUB-CLOUD AIR
CONTINUING TO ADVECT IN FROM THE WEST. SO HAVE A MORE OPTIMISTIC
FORECAST THAT MOST MODELS WOULD SUGGEST FOR CLOUD BASES THROUGH
TONIGHT AND SAT MORNING.
THE NEXT ALBERTA CLIPPER WEATHER SYSTEM WILL MOVE SOUTHEAST OVER
THE REGION SAT AFTERNOON INTO EVENING...WITH THE SURFACE LOW
DEVELOPING SOUTHEAST FROM IA INTO CENTRAL IN THROUGH THAT TIME.
SNOW LOOKS TO ENVELOP THE AREA WITH RFD SEEING THE MORE FREQUENT
MODEST RATES. FORCING FOR MODEST SNOW WILL BE SEEN OVER CHICAGO
TAF SITES FROM THE MID AFTERNOON-EARLY EVE. WITH CLIPPERS THE
VISIBILITY TENDS TO COME DOWN QUICKLY...AND THE WARM AIR ADVECTION
IS ENOUGH THAT THE CIGS SHOULD TOO. IT IS CERTAINLY POSSIBLE FOR
IFR CIGS AT CHICAGO SITES BUT WILL NEED TO BE FURTHER REFINED IN
TIME.
//ORD AND MDW CONFIDENCE...UPDATED 03Z...
* MEDIUM CONFIDENCE IN NO FURTHER MVFR CIGS...AND HIGH CONFIDENCE
ANY WILL BE ABOVE 1500 FT.
* HIGH CONFIDENCE IN SNOW ON SAT AFTERNOON INTO EARLY SAT EVE.
MEDIUM CONFIDENCE IN VISBY AND CIGS DURING. LOW CONFIDENCE ON
WHETHER IFR CIGS WILL BE ATTAINED.
* HIGH CONFIDENCE IN WIND TRENDS THROUGH 00Z SUN INCLUDING
SOUTHEAST TO EAST WINDS AT 10 KT. MEDIUM CONFIDENCE ON WIND
SHIFT TIME TO NORTHWEST.
//OUTLOOK FOR ORD/MDW FOR 12Z SUNDAY-12Z FRIDAY...UPDATED 00Z...
SUNDAY...MVFR POSSIBLE...MAINLY SUNDAY NIGHT. GUSTY SW WINDS.
MONDAY...SLGT CHC OF SNOW SHOWERS.
TUESDAY...MAINLY VFR.
WEDNESDAY-THURSDAY...SLGT CHC OF SNOW SHOWERS AND MVFR.
MTF
&&
.MARINE...
300 PM...
A SERIES OF CLIPPER-TYPE SYSTEMS WILL TRACK THROUGH THE GREAT
LAKES REGION OVER THE NEXT SEVERAL DAYS. THIS WILL BRING PERIODS
OF INCREASING AND DECREASING WINDS OF VARIABLE DIRECTION TO THE
LAKE. THE FIRST SYSTEM...OVER LAKE HURON...WILL CONTINUE TO
WEAKEN AS IT MOVES INTO QUEBEC LATE TONIGHT WHILE DRAGGING A WEAK
COLD FRONT SOUTH DOWN THE LAKE TURNING WINDS FROM WESTERLY TO
NORTHWESTERLY. THE NEXT SYSTEM WILL DROP OUT OF NORTHERN ALBERTA
LATE TONIGHT AND DEEPEN AS IT MOVES THROUGH MINNESOTA SATURDAY
MORNING. THIS LOW WILL SLOWLY WEAKEN AS IT TRACKS THROUGH CENTRAL
ILLINOIS SATURDAY AFTERNOON AND DISSIPATE AS IT REACHES THE UPPER
OHIO VALLEY SUNDAY. THIS WILL BE A PERIOD OF RELATIVELY LIGHTER
WINDS OVER THE LAKE...BUT ANOTHER...STRONGER...LOW IS EXPECTED TO
DEVELOP OVER NORTHERN MANITOBA FRIDAY NIGHT AND DROP SOUTHEAST
ACROSS ONTARIO SATURDAY NIGHT WHILE DEEPENING. STRENGTHENING WINDS
AHEAD OF AN ASSOCIATED COLD FRONT MAY APPROACH OR REACH GALE FORCE
SATURDAY NIGHT OR SUNDAY. HIGH PRESSURE WILL THEN BUILD IN BEHIND
THIS FRONT ALLOWING WINDS TO WEAKEN SOMEWHAT AGAIN. THIS PATTERN
SHOULD REPEAT AGAIN EARLY NEXT WEEK AS ANOTHER CLIPPER DROPS OUT
OF CANADA AND TRACKS THROUGH THE UPPER GREAT LAKES,
KREIN
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...WINTER WEATHER ADVISORY...ILZ010-ILZ019-ILZ021-ILZ032...6 AM
SATURDAY TO 6 PM SATURDAY.
WINTER WEATHER ADVISORY...ILZ023-ILZ033-ILZ039...10 AM SATURDAY
TO 9 PM SATURDAY.
IN...WINTER WEATHER ADVISORY...INZ019...10 AM SATURDAY TO 9 PM
SATURDAY.
LM...SMALL CRAFT ADVISORY...INDIANA NEARSHORE WATERS UNTIL 10 AM SATURDAY.
&&
$$
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FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
640 PM CST FRI JAN 17 2014
.DISCUSSION...
640 PM CST
EARLY EVENING UPDATE...
MINOR CHANGES TO FORECAST GRIDS/ZFP TO RAISE POPS ACROSS NORTHEAST
IL THROUGH EARLY EVENING...AS AREA OF LIGHT SNOW CONTINUES TO PIVOT
SLOWLY SOUTHEAST ACROSS THE REGION.
RECENT AMDAR ASCENT SOUNDING FROM KMDW CONTINUES TO DEPICT SATURATED
COLUMN FROM 900 MB THROUGH AROUND 775 MB...WITH ENTIRE MOIST LAYER
LOCATED WITHIN THE DENDRITIC GROWTH SWEET SPOT -15C TO -17C. WEAK
SHEARED MID-LEVEL VORT MAX ROTATING AROUND BACK SIDE OF LARGER SCALE
UPPER TROUGH AXIS IS PROVIDING WEAK BUT PERSISTENT FORCING
SUFFICIENT TO PRODUCE LIGHT SNOW WITH SOME MINOR ACCUMULATIONS.
TRENDS FROM SHORT TERM RAP GUIDANCE CONTINUES TO WEAKEN AND MOVE THE
VORT AXIS OFF TO THE SOUTHEAST THROUGH MID-EVENING...ALLOWING A
DECREASE IN INTENSITY OF THE LIGHT SNOW TO SCATTERED FLURRIES BY THE
LATE EVENING HOURS. THIS IS PRETTY MUCH IN LINE WITH PREVIOUS
FORECAST TRENDS...THOUGH HAVE INCREASED POPS IN NEXT FEW HOURS TO
CATEGORICAL ACROSS NORTHEAST IL WHERE LIGHT SNOW CURRENTLY PRODUCING
SOME LIGHT ACCUMS. FLUFFY NATURE OF SOME OF THE DENDRITES MAY ALLOW
UP TO A HALF INCH OF ADDITIONAL ACCUMULATION IN SOME SPOTS ACROSS
THE CHICAGO METRO AREA...COINCIDENT WITH SOME OF THE STRONG 20+ DBZ
RADAR RETURNS. DRIER AIR FILTERING IN FROM THE WEST MAY ALLOW SOME
PARTIAL CLEARING ACROSS NORTH CENTRAL IL...BEFORE RAPIDLY ADVANCING
CIRRUS SHIELD SPREADS IN AHEAD OF TOMORROWS CLIPPER.
RATZER
&&
.PREV DISCUSSION...
301 PM CST
REST OF TODAY AND TONIGHT...
AREA OF LIGHT SNOW CONTINUES TO PIVOT ACROSS NORTHERN ILLINOIS THIS
AFTERNOON ASSOCIATED WITH A SHEARED VORT LOBE ROTATING AROUND THE
MAIN UPPER TROUGH AXIS WHICH HAS SHIFTED EAST OF THE AREA.
SMALLER SCALE FORCING IS EMBEDDED WITHIN LARGER SCALE
SUBSIDENCE AS AN H5 RIDGE BUILDS OVER THE AREA OVERNIGHT. UPSTREAM
VSBY GENERALLY IN THE 2-5SM RANGE PERIODICALLY DROPPING
BELOW...INDICATING THAT MOST OF THE SNOW IS PRETTY LIGHT. EXPECT THE
AREA TO CONTINUE TO PIVOT EAST ACROSS NORTHERN ILLINOIS POSSIBLY
DROPPING A DUSTING OF SNOW WITH FLURRIES LINGERING INTO THE
EVENING.
SATURDAY...
ANOTHER ROUND OF SNOW IS EXPECTED ON SATURDAY WITH MODEST
ACCUMULATION APPEARING LIKELY. A 130KT JET DIGGING INTO THE UPPER
MIDWEST WITH A POTENT H5 VORT MAX AT THE NOSE OF THE JET WILL RACE
SOUTHEAST ACROSS IOWA INTO CENTRAL ILLINOIS SATURDAY AFTERNOON.
TAKING A LOOK FOR THE HOOK ON THE PV1.5 SURFACE...A TROP FOLD
EXTENDS DOWN TO ALMOST 600 MB SATURDAY AFTERNOON...WITH THE BEST
PRESSURE ADVECTION AND ASCENT FOCUSED ACROSS CENTRAL ILLINOIS
INCLUDING PORTIONS OF THE FAR SOUTHERN CWA WHERE THE SURFACE LOW IS
EXPECTED TO TRACK. ISENTROPIC SURFACES SIMILARLY INDICATE TIGHTEST
PACKING IN THE FAR WEST/SOUTH CWA WITH THE BEST FOCUSED ASCENT
AND RESULTING PRECIP AXIS EXTENDING FROM ROUGHLY DIXON ILLINOIS TO
FOWLER INDIANA. IN ADDITION...CROSS SECTIONS SHOW AN AREA OF
STRONGER F-GEN TRANSLATING ALONG THAT SAME LINE WITH NEGATIVE
SATURATED EPV RIGHT ON TOP OF THE LAYER OF BEST F-GEN...INDICATING
THE POTENTIAL FOR A DEEP VERTICAL RESPONSE AND BANDED SNOWFALL WITH
UNEVEN DISTRIBUTION OF THE SNOW TOTALS. UTILIZED A NAM/GFS QPF
BLEND FOR THIS PERIOD...AND SLIGHTLY HIGHER THAN AVERAGE SNOW RATIOS
AROUND 15-16:1...CAME UP WITH 3 TO 5 INCHES ALONG AND SOUTH OF THE
DIXON TO FOWLER LINE...WITH 1 TO 3 INCHES TO THE NORTH. THESE
AMOUNTS LINE UP WELL WITH GARCIA METHOD WHICH RESULTS IN ROUGHLY 3-4
INCHES...AND SREF PLUMES. AGAIN...WITH THE POTENTIAL FOR MESOSCALE
BANDING...THERE COULD BE SOME LOCALIZED HIGHER AMOUNTS OF 5 TO 6
INCHES WITHIN THE MAIN PRECIP AXIS ACROSS THE WEST/SOUTH PORTION OF
THE CWA. WILL GO AHEAD AND ISSUE A WINTER WEATHER ADVISORY FOR 3 TO
5 INCHES OF SNOW FOR THE AFFECTED AREAS.
SUNDAY AND MONDAY...
ON SUNDAY BROAD H5 HEIGHT RISES WILL BUILD ACROSS THE AREA WITH
TRANSIENT SURFACE RIDGE PROGRESSING ACROSS THE AREA EARLY IN THE
DAY. WINDS BACK TO THE SOUTHWEST BY SUNDAY AFTERNOON WITH H85
THERMAL GRADIENT LIFTING ACROSS THE AREA...WITH TEMPS APPROACHING
3-4C. SURFACE TEMPS SHOULD PUSH TO OR SLIGHTLY ABOVE THE FREEZING
MARK...TEMPERED SOME BY SATURDAYS SNOWPACK. ANOTHER SHORTWAVE WILL
BRUSH JUST NORTH OF THE AREA SUNDAY NIGHT WITH A COLD FRONT PUSHING
SOUTH ACROSS THE AREA THROUGH THE DAY MONDAY. MOISTURE SOMEWHAT
SHALLOW BEHIND THE FRONT...BUT STEEP LOW LEVEL LAPSE RATES WITH EVEN
SOME UPRIGHT INSTABILITY NOTED ON THE SOUNDINGS INDICATE THE
POTENTIAL FOR AT LEAST SOME FLURRIES IF NOT A FEW SNOW SHOWERS.
DEPENDING ON THE EXACT TIMING OF THE FRONT...COULD SEE TEMPS FALLING
THROUGH THE DAY MONDAY. TAKING A STEP BACK AND LOOKING AT THE BIGGER
PICTURE FOR MONDAY...STRONG RIDGING OVER THE WEST COAST AND ALASKA
THIS WEEKEND WILL HELP DISLODGE AN ARCTIC AIRMASS WHICH WILL SINK
INTO GREAT LAKES MONDAY WITH THE LEADING EDGE REACHING NEAR THE OHIO
VALLEY BY MONDAY EVENING. THE COLDEST AIR AROUND -30C WILL STAY
PRIMARILY OVER THE NORTHERN LAKES REGION BUT MODELS CONTINUE TO SHOW
-20C AIR REACHING INTO ILLINOIS RESULTING IN ANOTHER PERIOD OF
FRIGID CONDITIONS AS WE HEAD INTO NEXT WEEK.
DEUBELBEISS
LONG TERM...MONDAY NIGHT THROUGH THURSDAY...
THE UPPER LEVEL TROUGH REMAINS OVERHEAD WITH SUBSEQUENT TROUGH
AXES PASS OVER THE REGION MONDAY NIGHT AND MID TO LATE NEXT WEEK.
AT THE SURFACE...HIGH PRESSURE BUILDS OVER THE GREAT PLAINS AND
MIDWEST MONDAY NIGHT THROUGH TUESDAY NIGHT. LOW PRESSURE PASSES TO
THE NORTH MID WEEK WITH HIGH PRESSURE BUILDING IN BEHIND IT.
GIVEN THE MODEL DISCREPANCIES REGARDING WHEN THE UPPER LEVEL TROUGH
AXIS/SURFACE LOW WILL PASS THROUGH THE REGION...KEPT POPS IN THE
SLIGHT CHANCE TO CHANCE RANGE MID TO LATE NEXT WEEK. THE ECMWF IS
FASTER AND FEATURES A MUCH STRONGER LOW...BUT WILL RESIST LEANING
TOO MUCH IN ITS DIRECTION.
FOR TEMPS...COLD AIR MOVES IN MONDAY NIGHT WITH 925MB TEMPS FALLING
TO -16 TO -22C. LOWERED MONDAY NIGHT/S LOWS A BIT...BUT ONCE AGAIN
WAITING FOR MODELS TO COME INTO BETTER ALIGNMENT BEFORE MAKING MAJOR
CHANGES. TUESDAY NIGHT LOOKS TO BE THE COLDEST WITH CONTINUED COLD
AIR UPSTAIRS AND A SURFACE HIGH OVERHEAD. LOWS BTWN 0 AND -10F IF
NOT COLDER ARE EXPECTED. BRIEF WAA ON WEDNESDAY WILL LEAD TO HIGH
TEMPS ABOVE 0. TEMPS AROUND ZERO ARE EXPECTED AGAIN WEDNESDAY NIGHT
WITH BELOW NORMAL TEMPS CONTINUING THROUGH LATE NEXT WEEK.
JEE
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 00Z...
* SNOW WITH MVFR AND TEMPORARY IFR VISIBILITY THROUGH MID EVE
TAPERING TO FLURRIES.
* PERIODIC MVFR CIGS THROUGH MID EVE AND POSSIBLY INTO OVERNIGHT.
* ACCUMULATING SNOW WITH IFR CONDITIONS BEGINNING MID AFTERNOON
SAT AND PERSISTING INTO EARLY SAT EVE.
* SOUTHEAST TO EAST WINDS AROUND 10 KT BY MID SAT AFTERNOON INTO
EARLY SAT EVE...BECOMING NORTHWEST BY MID EVE.
//DISCUSSION...UPDATED 00Z...
LOW PRESSURE CONTINUES TO PULL AWAY FROM THE EASTERN GREAT LAKES
REGION WITH UPPER LEVEL FORCING CONTINUING TO SUPPORT SNOW EARLY
THIS EVE. AS THIS FORCING SLOWLY FADES THE SNOW WILL FOLLOW
SUIT...TAPERING TO FLURRIES. CIGS BELOW 2000 FT HAVE BEEN VERY
PATCHY AND THAT LIKELY HAS TO DO WITH DRY SUB-CLOUD AIR
CONTINUING TO ADVECT IN FROM THE WEST. SO HAVE A MORE OPTIMISTIC
FORECAST THAT MOST MODELS WOULD SUGGEST FOR CLOUD BASES THROUGH
TONIGHT AND SAT MORNING.
THE NEXT ALBERTA CLIPPER WEATHER SYSTEM WILL MOVE SOUTHEAST OVER
THE REGION SAT AFTERNOON INTO EVENING...WITH THE SURFACE LOW
DEVELOPING SOUTHEAST FROM IA INTO CENTRAL IN THROUGH THAT TIME.
SNOW LOOKS TO ENVELOP THE AREA WITH RFD SEEING THE MORE FREQUENT
MODEST RATES. FORCING FOR MODEST SNOW WILL BE SEEN OVER CHICAGO
TAF SITES FROM THE MID AFTERNOON-EARLY EVE. WITH CLIPPERS THE
VISIBILITY TENDS TO COME DOWN QUICKLY...AND THE WARM AIR ADVECTION
IS ENOUGH THAT THE CIGS SHOULD TOO. IT IS CERTAINLY POSSIBLE FOR
IFR CIGS AT CHICAGO SITES BUT WILL NEED TO BE FURTHER REFINED IN
TIME.
//ORD AND MDW CONFIDENCE...UPDATED 00Z...
* MEDIUM CONFIDENCE IN SNOW AND VISIBILITY TRENDS THIS EVE.
* HIGH CONFIDENCE IN SNOW ON SAT AFTERNOON INTO EARLY SAT EVE.
MEDIUM CONFIDENCE IN VISBY AND CIGS DURING. LOW CONFIDENCE ON
WHETHER IFR CIGS WILL BE ATTAINED.
* HIGH CONFIDENCE IN WIND TRENDS THROUGH 00Z SUN INCLUDING
SOUTHEAST TO EAST WINDS AT 10 KT. MEDIUM CONFIDENCE ON WIND
SHIFT TIME TO NORTHWEST.
//OUTLOOK FOR ORD/MDW FOR 12Z SUNDAY-12Z FRIDAY...UPDATED 00Z...
SUNDAY...MVFR POSSIBLE...MAINLY SUNDAY NIGHT. GUSTY SW WINDS.
MONDAY...SLGT CHC OF SNOW SHOWERS.
TUESDAY...MAINLY VFR.
WEDNESDAY-THURSDAY...SLGT CHC OF SNOW SHOWERS AND MVFR.
MTF
&&
.MARINE...
300 PM...
A SERIES OF CLIPPER-TYPE SYSTEMS WILL TRACK THROUGH THE GREAT
LAKES REGION OVER THE NEXT SEVERAL DAYS. THIS WILL BRING PERIODS
OF INCREASING AND DECREASING WINDS OF VARIABLE DIRECTION TO THE
LAKE. THE FIRST SYSTEM...OVER LAKE HURON...WILL CONTINUE TO
WEAKEN AS IT MOVES INTO QUEBEC LATE TONIGHT WHILE DRAGGING A WEAK
COLD FRONT SOUTH DOWN THE LAKE TURNING WINDS FROM WESTERLY TO
NORTHWESTERLY. THE NEXT SYSTEM WILL DROP OUT OF NORTHERN ALBERTA
LATE TONIGHT AND DEEPEN AS IT MOVES THROUGH MINNESOTA SATURDAY
MORNING. THIS LOW WILL SLOWLY WEAKEN AS IT TRACKS THROUGH CENTRAL
ILLINOIS SATURDAY AFTERNOON AND DISSIPATE AS IT REACHES THE UPPER
OHIO VALLEY SUNDAY. THIS WILL BE A PERIOD OF RELATIVELY LIGHTER
WINDS OVER THE LAKE...BUT ANOTHER...STRONGER...LOW IS EXPECTED TO
DEVELOP OVER NORTHERN MANITOBA FRIDAY NIGHT AND DROP SOUTHEAST
ACROSS ONTARIO SATURDAY NIGHT WHILE DEEPENING. STRENGTHENING WINDS
AHEAD OF AN ASSOCIATED COLD FRONT MAY APPROACH OR REACH GALE FORCE
SATURDAY NIGHT OR SUNDAY. HIGH PRESSURE WILL THEN BUILD IN BEHIND
THIS FRONT ALLOWING WINDS TO WEAKEN SOMEWHAT AGAIN. THIS PATTERN
SHOULD REPEAT AGAIN EARLY NEXT WEEK AS ANOTHER CLIPPER DROPS OUT
OF CANADA AND TRACKS THROUGH THE UPPER GREAT LAKES,
KREIN
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...WINTER WEATHER ADVISORY...ILZ010-ILZ019-ILZ021-ILZ032...6 AM
SATURDAY TO 6 PM SATURDAY.
WINTER WEATHER ADVISORY...ILZ023-ILZ033-ILZ039...10 AM SATURDAY
TO 9 PM SATURDAY.
IN...WINTER WEATHER ADVISORY...INZ019...10 AM SATURDAY TO 9 PM
SATURDAY.
LM...SMALL CRAFT ADVISORY...INDIANA NEARSHORE WATERS UNTIL 10 AM SATURDAY.
&&
$$
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AREA FORECAST DISCUSSION
NWS TOPEKA KS
1150 AM CST Thu Jan 16 2014
...Update to aviation forecast discussion...
.SHORT TERM...(Today and Tonight)
Issued at 317 AM CST THU JAN 16 2014
Mid level shortwave and associated vorticity was located over IA and
NE around 09Z and will continue to dig southward through out the day
today. This wave is pushing a surface cold front southward which is
currently located across portions of southeast and south central NE.
Winds ahead of the front are light out of the west although directly
behind the front become northwesterly and increase rapidly. Forecast
soundings continue to show that the boundary will mix into 50-60 kts
winds as early as 10 am lasting through most of the afternoon. There
are a few factors that could limit the momentum transfer of the wind
today which include weak subsidence and stratus within the mixing
layer. The stratus should remain confined to far northeast KS during
the afternoon hours while partly cloudy elsewhere. The last few runs
of the RAP and HRRR continue to agree that most areas along and
north of interstate 35 will experience surface gusts around 35-45
kts and approaching 50 kts in the far northwest portion of the
forecast area. Therefore have upgraded the advisory to a high wind
warning in that location. The strongest wind gusts should subside
around sunset this evening although will remain gusty through most
of the night. High temperatures today are generally in the 40s
although look to occur mostly before noon. There is a slight chance
for sprinkles and or flurries in far northeast KS during the
afternoon and evening as a vort max rotates through the trough axis.
During the afternoon cold air advection increases sending
temperatures into the mid to upper 10s by Friday
morning.
.LONG TERM...(Friday through Wednesday)
Issued at 317 AM CST THU JAN 16 2014
A longer wave-length upper level trough will continue across the
east central conus with a longer wave-length upper level ridge
along the the western coast of North America through the forecast
period.
The amplified upper level trough across the eastern conus will move
east into the mid Atlantic states on Sunday. A secondary upper level
trough will dig southeast across the Great Lakes States into the Mid
Atlantic States on Sunday.
Friday and Friday night, a surface ridge of high pressure will shift
southeast of the CWA by late afternoon. Northwest winds will
diminish during the early afternoon hours and become southerly
across north central KS. Highs Friday will only reach the lower to
mid 30s across northeast and east central KS, with lower 40s across
north central KS. Lows Friday night will drop into the 20s, shortly
after midnight with temperatures remaining steady or lowly rising
through the morning hours of Saturday.
Saturday, as the H5 trough digs southeast across the Great Lakes a weak
cold front will push southward across the CWA during the afternoon
hours. Highs ahead of the front should warm into the upper 40s to
around 50 degrees across much of the CWA. Temperatures across the
northern counties could slowly fall through the 40s during the mid
and late afternoon hours as winds shift from the west-southwest to
the northwest.
Sunday, The upper flow will become more zonal as a lee surface
trough deepens across western KS and southeast CO. Southwest surface
winds will advect warmer downslope air northeast across central
and eastern KS. Highs will warm into the mid 50s to around 60
degrees with mostly sunny skies.
Another upper level trough will dig southeast out west central
Canada and across the northern plains, and into the mid MS river
valley and OH river valley. This will bring a surge of colder air
southward across the northern plains into eastern KS. Highs on
Monday will cool into the mid 40s to around 50 and down into the
30s to around 40 on Tuesday.
&&
.AVIATION...(For the 18Z TAFs through 18Z Friday Afternoon)
Issued at 1143 AM CST THU JAN 16 2014
VFR conditions should persist. Strong northwest winds will
continue to be the biggest impact. A few gusts may breach the
forecast, but think they will hold the vast majority of
conditions. BKN deck could drop down to near MVFR levels but again
expect brief issues at worst.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY until 7 PM CST this evening FOR KSZ009>012-021>024-
026-034>040-054>056-058-059.
HIGH WIND WARNING until 7 PM CST this evening FOR KSZ008-020.
&&
$$
SHORT TERM...Sanders
LONG TERM...Gargan
AVIATION...65
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1025 AM MST THU JAN 16 2014
.SHORT TERM...(TODAY THROUGH SATURDAY NIGHT)
ISSUED AT 308 AM MST THU JAN 16 2014
LATEST WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOWS AT THE 500MB
LEVEL STRONG 585DM RIDGE OVER THE EASTERN PACIFIC WITH EASTERN
FLANK EXTENDING TO GREAT BASIN...AND 511DM CLOSED LOW CENTERED
NORTH OF THE GREAT LAKES REGION IN CANADA. BETWEEN THESE FEATURES
DEEP SURFACE-300MB UNIDIRECTIONAL GRADIENT HAS DEVELOPED ACROSS
THE PLAINS. UPSTREAM VWP WOULD INDICATE A 75+ JET AT 700MB AND
95+JET AT 500MB ALREADY OVER NORTHERN NEBRASKA. A STRONG PV15
HEIGHT ANOMALY IS CURRENTLY OVER NORTHERN NEBRASKA IN LINE WITH A
SHORTWAVE TROUGH AXIS ROUNDING THE WESTERN FLANK OF THE LARGE
SCALE TROUGH. STRONG SUBSIDENCE NORTH OF THIS FEATURE IS EVIDENT
BY MID LEVEL DRYING ON WV IMAGERY WHICH EXTENDS ACROSS THE WESTERN
DAKOTAS/EASTERN MONTANA. EAST OF THIS IS A PLUME MOISTURE ON WV
IMAGERY EXTENDING FROM THE CANADIAN ROCKIES ACROSS EASTERN MONTANA
ASSOCIATED WITH CIRRUS DECK.
AXIS OF MID-HIGH CLOUDS EXPECTED TO MOVE SOUTH OVER CWA AS FRONT
QUICKLY MOVES SOUTH THIS MORNING...WITH MOUNTAIN WAVE CIRRUS
POSSIBLY MOVING THROUGH ACROSS SW CWA DURING THE DAY. AREA OF
STRONG SUBSIDENCE ON WV IMAGERY SHOULD MOVE SOUTH OVER OUR
CWA...SUPPORTING GOOD DOWNWARD MOTION AND CLEARING IN THE EAST.
HIGH CLOUDS COULD HAVE IMPACT ON MIXING POTENTIAL TODAY IN THE
WEST...HOWEVER MODEL SOUNDINGS CONTINUE TO INDICATE VERY DRY
MOISTURE PROFILES ACROSS THE CWA...AND CURRENT ORIENTATION OF
MOISTURE PLUME ON WV MATCHING H5-H3 MODEL RH WOULD INDICATE
CIRRUS MAINLY IMPACTING OUR FAR WEST/SW WHERE MODEL WINDS ARE
ALREADY LIGHTER.
LATEST RAP HAS COME IN STRONGER WITH WIND AT TOP OF MIXED LAYER
OVER CHEYENNE COUNTY COLORADO AND GREELEY KS NEAR 50KT. ALL
OTHER GUIDANCE IS LOWER WITH VALUES IN THE 35-45KT RANGE...AND
LATEST HRRR WIND GUST FIELD KEEPS GUSTS SUB WARNING OVER THESE
COUNTIES. WITH CONCERN ALREADY REGARDING CLOUDS I THINK THE
ONGOING WIND ADVISORY COVERS POTENTIAL GUSTS FOR THESE TWO
COUNTIES..
TOP OF MIXED LAYER ON ALL GUIDANCE ACROSS REST OF CWA IS IN THE
800-780MB LAYER AND STILL SUPPORTS WIND GUSTS IN THE 50-55KT RANGE.
ALL MODELS SHOW MUCH STRONGER WINDS IN THE 60KT+ RANGE (MATCH
TRENDS ON UPSTREAM VWP)...AND IF THESE STRONGER WINDS WERE TO
MIX DOWN WE COULD SEE WINDS AS HIGH AS 80MPH. BASED ON CURRENT
MODEL MIXING HEIGHTS THIS IS NOT ANTICIPATED...BUT IT IS WORTH
MONITORING FOR POSSIBLE DAYTIME UPDATES.
FRIDAY-SATURDAY...AIR MASS BEGINS TO MODERATE WITH ABOVE NORMAL
TEMPS RETURNING BY THIS WEEKEND. WHILE WE GET A REPRIEVE FROM
WINDY CONDITIONS FRIDAY...LATEST GUIDANCE IS INDICATING ANOTHER
QUICK MOVING SHORTWAVE TROUGH OVER THE NORTHERN PLAINS WHICH COULD
BRING ADVISORY LEVEL WINDS (GUSTS 45MPH+) TO OUR CWA. WILL NEED TO
MONITOR.
.LONG TERM...(SUNDAY THROUGH WEDNESDAY)
ISSUED AT 308 AM MST THU JAN 16 2014
NEXT WEEK LOOKS SIMILAR TO THIS WEEK WITH MILD TEMPS AND A
PERSISTENT NORTHWEST WIND. NO MEASURABLE PRECIP IN SIGHT GIVEN THE
CURRENT PATTERN. AT THE SYNOPTIC SCALE A RIDGE CONTINUES TO DOMINATE
THE WESTERN CONUS AND A BROAD TROUGH ACROSS THE EAST. THE ONLY
NOTICEABLE SYNOPTIC FEATURE FOR THE CENTRAL PLAINS WILL BE A SHOT OF
COLD AIR ARRIVING LATE MONDAY INTO TUESDAY. LOCALLY THE FRONT
ASSOCIATED WITH THIS COLD AIR WILL NOT BE ESPECIALLY STRONG AS THE
BEST FORCING WILL BE FARTHER EAST.
SENSIBLE WX BENIGN FOR THE PERIOD. MILD ON SUNDAY WITH A SURFACE
TROUGH SETTING UP ACROSS EASTERN COLORADO AND WEST TO SOUTHWEST
WINDS AT THE SURFACE AND ALOFT. ECMWF HAS BEEN CONSISTENT WITH 850MB
TEMPS IN THE LOWER TEENS AND FULL SUNSHINE WILL LEAD TO HIGHS IN THE
LOW 60S...POSSIBLY APPROACHING THE RECORD HIGHS AT MCK AND HLC
WHICH ARE ONLY 66. GEM IS SIMILAR...BUT GFS IS NOT AS WARM. A WEAK
SHORTWAVE TROUGH AND ASSOCIATED FRONT WILL MOVE THROUGH MID TO LATE
SUNDAY SHIFTING WINDS TO THE NORTH AND BRINGING MORE SEASONABLE AIR
FOR THE START OF THE WORK WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1018 AM MST THU JAN 16 2014
SURFACE WINDS WILL CONTINUE TO INCREASE AT BOTH KGLD AND KMCK
THROUGH THE AFTERNOON. THE MAIN UPPER JET AXIS WILL BE LOCATED
DIRECTLY OVER THE REGION. SUBSIDENCE BEHIND A DEPARTING
DISTURBANCE COMBINED WITH MIXING WITH DAYTIME HEATING WILL BRING
SOME OF THOSE STRONG WINDS TO THE SURFACE. MAXIMUM GUSTS ARE
EXPECTED TO BE IN THE 50-60KT RANGE BETWEEN 19Z AND 21Z. AREAS OF
BLOWING DUST WILL LIKELY DEVELOP AND SIGNIFICANT VISIBILITY
RESTRICTIONS ARE POSSIBLE AT BOTH TERMINALS. WINDS WILL DIMINISH
EARLY THIS EVENING.
&&
.FIRE WEATHER...
ISSUED AT 302 AM MST THU JAN 16 2014
REGARDING RFW CONDITIONS...WITH VERY STRONG WINDS AND VERY DRY/CURED
FUELS THERE IS A CONCERN FOR DANGEROUS FIRE CONDITIONS. THE ONE
CAVEAT IS RH VALUES RIGHT AT 20 PERCENT ACROSS MOST OF THE AREA AND
APPROACHING 40 PERCENT IN THE WEST TODAY. WHILE THESE RH VALUES ARE
CERTAINLY MARGINAL IN THE WEST...AFTER PREVIOUSLY COORDINATING
WITH PARTNERS IT WAS DECIDED TO COVER OUR ENTIRE AREA WITH AN
RFW DURING THE EVENING SHIFT...AND I SEE NO REASON TO MAKE A CHANGE
CONSIDERING THE IMPACT OF THE WINDS ON THE ALREADY CURED FUELS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...HIGH WIND WARNING UNTIL 7 PM MST /8 PM CST/ THIS EVENING FOR
KSZ001>004-013>016-027>029-042.
RED FLAG WARNING UNTIL 5 PM MST /6 PM CST/ THIS AFTERNOON FOR
KSZ001>004-013>016-027>029-041-042.
WIND ADVISORY UNTIL 7 PM MST THIS EVENING FOR KSZ041.
CO...HIGH WIND WARNING UNTIL 7 PM MST THIS EVENING FOR COZ090-091.
RED FLAG WARNING UNTIL 5 PM MST THIS AFTERNOON FOR COZ252>254.
WIND ADVISORY UNTIL 7 PM MST THIS EVENING FOR COZ092.
NE...HIGH WIND WARNING UNTIL 7 PM MST /8 PM CST/ THIS EVENING FOR
NEZ079>081.
RED FLAG WARNING UNTIL 5 PM MST /6 PM CST/ THIS AFTERNOON FOR
NEZ079>081.
&&
$$
SHORT TERM...DR
LONG TERM...JJM
AVIATION...024
FIRE WEATHER...DR
AREA FORECAST DISCUSSION
NWS TOPEKA KS
546 AM CST Thu Jan 16 2014
...Update to aviation forecast discussion...
.SHORT TERM...(Today and Tonight)
Issued at 317 AM CST THU JAN 16 2014
Mid level shortwave and associated vorticity was located over IA and
NE around 09Z and will continue to dig southward through out the day
today. This wave is pushing a surface cold front southward which is
currently located across portions of southeast and south central NE.
Winds ahead of the front are light out of the west although directly
behind the front become northwesterly and increase rapidly. Forecast
soundings continue to show that the boundary will mix into 50-60 kts
winds as early as 10 am lasting through most of the afternoon. There
are a few factors that could limit the momentum transfer of the wind
today which include weak subsidence and stratus within the mixing
layer. The stratus should remain confined to far northeast KS during
the afternoon hours while partly cloudy elsewhere. The last few runs
of the RAP and HRRR continue to agree that most areas along and
north of interstate 35 will experience surface gusts around 35-45
kts and approaching 50 kts in the far northwest portion of the
forecast area. Therefore have upgraded the advisory to a high wind
warning in that location. The strongest wind gusts should subside
around sunset this evening although will remain gusty through most
of the night. High temperatures today are generally in the 40s
although look to occur mostly before noon. There is a slight chance
for sprinkles and or flurries in far northeast KS during the
afternoon and evening as a vort max rotates through the trough axis.
During the afternoon cold air advection increases sending
temperatures into the mid to upper 10s by Friday
morning.
.LONG TERM...(Friday through Wednesday)
Issued at 317 AM CST THU JAN 16 2014
A longer wave-length upper level trough will continue across the
east central conus with a longer wave-length upper level ridge
along the the western coast of North America through the forecast
period.
The amplified upper level trough across the eastern conus will move
east into the mid Atlantic states on Sunday. A secondary upper level
trough will dig southeast across the Great Lakes States into the Mid
Atlantic States on Sunday.
Friday and Friday night, a surface ridge of high pressure will shift
southeast of the CWA by late afternoon. Northwest winds will
diminish during the early afternoon hours and become southerly
across north central KS. Highs Friday will only reach the lower to
mid 30s across northeast and east central KS, with lower 40s across
north central KS. Lows Friday night will drop into the 20s, shortly
after midnight with temperatures remaining steady or lowly rising
through the morning hours of Saturday.
Saturday, as the H5 trough digs southeast across the Great Lakes a weak
cold front will push southward across the CWA during the afternoon
hours. Highs ahead of the front should warm into the upper 40s to
around 50 degrees across much of the CWA. Temperatures across the
northern counties could slowly fall through the 40s during the mid
and late afternoon hours as winds shift from the west-southwest to
the northwest.
Sunday, The upper flow will become more zonal as a lee surface
trough deepens across western KS and southeast CO. Southwest surface
winds will advect warmer downslope air northeast across central
and eastern KS. Highs will warm into the mid 50s to around 60
degrees with mostly sunny skies.
Another upper level trough will dig southeast out west central
Canada and across the northern plains, and into the mid MS river
valley and OH river valley. This will bring a surge of colder air
southward across the northern plains into eastern KS. Highs on
Monday will cool into the mid 40s to around 50 and down into the
30s to around 40 on Tuesday.
&&
.AVIATION...(For the 12Z TAFs through 12Z Friday Morning)
Issued at 543 AM CST THU JAN 16 2014
VFR conditions are expected through the TAF period. The latest
data as well as the sounding at TOP does not show much of an issue
with low level wind shear this morning as previously thought. It
is rather borderline with about 40-45 kts of shear in the lowest 2
kft and should only last a few hours. Winds are still forecast to
increase later this morning and last most of the period with the
exception of MHK which may drop the gusts earlier towards the end
of the period.
&&
.FIRE WEATHER...
Issued at 543 AM CST THU JAN 16 2014
Very high rangeland fire danger criteria will be met across much of
north central, northeast and east central KS this Afternoon. Minimum
RH`s will drop to 25 to 35 percent along with very strong
northwest winds of 30 to 40 MPH with gusts of 40 to 55 MPH, even
some 60 MPH wind gusts across Republic and Cloud counties. Given
the strong northwest winds and dry fuels, any outdoor burning will
lead to uncontrollable wild fires late this morning and through
the afternoon hours. All planned outdoor burning Today will need
to be rescheduled.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY from 10 AM this morning to 7 PM CST this evening
FOR KSZ009>012-021>024-026-034>040-054-055.
HIGH WIND WARNING from 10 AM this morning to 7 PM CST this
evening FOR KSZ008-020.
&&
$$
SHORT TERM...Sanders
LONG TERM...Gargan
AVIATION...Sanders
FIRE WEATHER...Gargan
AREA FORECAST DISCUSSION
NWS TOPEKA KS
534 AM CST Thu Jan 16 2014
...Update to aviation forecast discussion...
.SHORT TERM...(Today and Tonight)
Issued at 317 AM CST THU JAN 16 2014
Mid level shortwave and associated vorticity was located over IA and
NE around 09Z and will continue to dig southward through out the day
today. This wave is pushing a surface cold front southward which is
currently located across portions of southeast and south central NE.
Winds ahead of the front are light out of the west although directly
behind the front become northwesterly and increase rapidly. Forecast
soundings continue to show that the boundary will mix into 50-60 kts
winds as early as 10 am lasting through most of the afternoon. There
are a few factors that could limit the momentum transfer of the wind
today which include weak subsidence and stratus within the mixing
layer. The stratus should remain confined to far northeast KS during
the afternoon hours while partly cloudy elsewhere. The last few runs
of the RAP and HRRR continue to agree that most areas along and
north of interstate 35 will experience surface gusts around 35-45
kts and approaching 50 kts in the far northwest portion of the
forecast area. Therefore have upgraded the advisory to a high wind
warning in that location. The strongest wind gusts should subside
around sunset this evening although will remain gusty through most
of the night. High temperatures today are generally in the 40s
although look to occur mostly before noon. There is a slight chance
for sprinkles and or flurries in far northeast KS during the
afternoon and evening as a vort max rotates through the trough axis.
During the afternoon cold air advection increases sending
temperatures into the mid to upper 10s by Friday
morning.
.LONG TERM...(Friday through Wednesday)
Issued at 317 AM CST THU JAN 16 2014
A longer wave-length upper level trough will continue across the
east central conus with a longer wave-length upper level ridge
along the the western coast of North America through the forecast
period.
The amplified upper level trough across the eastern conus will move
east into the mid Atlantic states on Sunday. A secondary upper level
trough will dig southeast across the Great Lakes States into the Mid
Atlantic States on Sunday.
Friday and Friday night, a surface ridge of high pressure will shift
southeast of the CWA by late afternoon. Northwest winds will
diminish during the early afternoon hours and become southerly
across north central KS. Highs Friday will only reach the lower to
mid 30s across northeast and east central KS, with lower 40s across
north central KS. Lows Friday night will drop into the 20s, shortly
after midnight with temperatures remaining steady or lowly rising
through the morning hours of Saturday.
Saturday, as the H5 trough digs southeast across the Great Lakes a weak
cold front will push southward across the CWA during the afternoon
hours. Highs ahead of the front should warm into the upper 40s to
around 50 degrees across much of the CWA. Temperatures across the
northern counties could slowly fall through the 40s during the mid
and late afternoon hours as winds shift from the west-southwest to
the northwest.
Sunday, The upper flow will become more zonal as a lee surface
trough deepens across western KS and southeast CO. Southwest surface
winds will advect warmer downslope air northeast across central
and eastern KS. Highs will warm into the mid 50s to around 60
degrees with mostly sunny skies.
Another upper level trough will dig southeast out west central
Canada and across the northern plains, and into the mid MS river
valley and OH river valley. This will bring a surge of colder air
southward across the northern plains into eastern KS. Highs on
Monday will cool into the mid 40s to around 50 and down into the
30s to around 40 on Tuesday.
&&
.AVIATION...(For the 12Z TAFs through 12Z Friday Morning)
Issued at 526 AM CST THU JAN 16 2014
VFR conditions are expected through the TAF period. The latest
data as well as the sounding at TOP does not show much of an issue
with low level wind shear this morning as previously thought.
Winds are still forecast to increase later this morning and last
most of the period with the exception of MHK which may drop the
gusts earlier towards the end of the period.
&&
.FIRE WEATHER...
Issued at 526 AM CST THU JAN 16 2014
Very high rangeland fire danger criteria will be met across much of
north central, northeast and east central KS this Afternoon. Minimum
RH`s will drop to 25 to 35 percent along with very strong
northwest winds of 30 to 40 MPH with gusts of 40 to 55 MPH, even
some 60 MPH wind gusts across Republic and Cloud counties. Given
the strong northwest winds and dry fuels, any outdoor burning will
lead to uncontrollable wild fires late this morning and through
the afternoon hours. All planned outdoor burning Today will need
to be rescheduled.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY from 10 AM this morning to 7 PM CST this evening
FOR KSZ009>012-021>024-026-034>040-054-055.
HIGH WIND WARNING from 10 AM this morning to 7 PM CST this
evening FOR KSZ008-020.
&&
$$
SHORT TERM...Sanders
LONG TERM...Gargan
AVIATION...Sanders
FIRE WEATHER...Gargan
AREA FORECAST DISCUSSION
NWS GOODLAND KS
423 AM MST THU JAN 16 2014
.SHORT TERM...(TODAY THROUGH SATURDAY NIGHT)
ISSUED AT 308 AM MST THU JAN 16 2014
LATEST WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOWS AT THE 500MB
LEVEL STRONG 585DM RIDGE OVER THE EASTERN PACIFIC WITH EASTERN
FLANK EXTENDING TO GREAT BASIN...AND 511DM CLOSED LOW CENTERED
NORTH OF THE GREAT LAKES REGION IN CANADA. BETWEEN THESE FEATURES
DEEP SURFACE-300MB UNIDIRECTIONAL GRADIENT HAS DEVELOPED ACROSS
THE PLAINS. UPSTREAM VWP WOULD INDICATE A 75+ JET AT 700MB AND
95+JET AT 500MB ALREADY OVER NORTHERN NEBRASKA. A STRONG PV15
HEIGHT ANOMALY IS CURRENTLY OVER NORTHERN NEBRASKA IN LINE WITH A
SHORTWAVE TROUGH AXIS ROUNDING THE WESTERN FLANK OF THE LARGE
SCALE TROUGH. STRONG SUBSIDENCE NORTH OF THIS FEATURE IS EVIDENT
BY MID LEVEL DRYING ON WV IMAGERY WHICH EXTENDS ACROSS THE WESTERN
DAKOTAS/EASTERN MONTANA. EAST OF THIS IS A PLUME MOISTURE ON WV
IMAGERY EXTENDING FROM THE CANADIAN ROCKIES ACROSS EASTERN MONTANA
ASSOCIATED WITH CIRRUS DECK.
AXIS OF MID-HIGH CLOUDS EXPECTED TO MOVE SOUTH OVER CWA AS FRONT
QUICKLY MOVES SOUTH THIS MORNING...WITH MOUNTAIN WAVE CIRRUS
POSSIBLY MOVING THROUGH ACROSS SW CWA DURING THE DAY. AREA OF
STRONG SUBSIDENCE ON WV IMAGERY SHOULD MOVE SOUTH OVER OUR
CWA...SUPPORTING GOOD DOWNWARD MOTION AND CLEARING IN THE EAST.
HIGH CLOUDS COULD HAVE IMPACT ON MIXING POTENTIAL TODAY IN THE
WEST...HOWEVER MODEL SOUNDINGS CONTINUE TO INDICATE VERY DRY
MOISTURE PROFILES ACROSS THE CWA...AND CURRENT ORIENTATION OF
MOISTURE PLUME ON WV MATCHING H5-H3 MODEL RH WOULD INDICATE
CIRRUS MAINLY IMPACTING OUR FAR WEST/SW WHERE MODEL WINDS ARE
ALREADY LIGHTER.
LATEST RAP HAS COME IN STRONGER WITH WIND AT TOP OF MIXED LAYER
OVER CHEYENNE COUNTY COLORADO AND GREELEY KS NEAR 50KT. ALL
OTHER GUIDANCE IS LOWER WITH VALUES IN THE 35-45KT RANGE...AND
LATEST HRRR WIND GUST FIELD KEEPS GUSTS SUB WARNING OVER THESE
COUNTIES. WITH CONCERN ALREADY REGARDING CLOUDS I THINK THE
ONGOING WIND ADVISORY COVERS POTENTIAL GUSTS FOR THESE TWO
COUNTIES..
TOP OF MIXED LAYER ON ALL GUIDANCE ACROSS REST OF CWA IS IN THE
800-780MB LAYER AND STILL SUPPORTS WIND GUSTS IN THE 50-55KT RANGE.
ALL MODELS SHOW MUCH STRONGER WINDS IN THE 60KT+ RANGE (MATCH
TRENDS ON UPSTREAM VWP)...AND IF THESE STRONGER WINDS WERE TO
MIX DOWN WE COULD SEE WINDS AS HIGH AS 80MPH. BASED ON CURRENT
MODEL MIXING HEIGHTS THIS IS NOT ANTICIPATED...BUT IT IS WORTH
MONITORING FOR POSSIBLE DAYTIME UPDATES.
FRIDAY-SATURDAY...AIR MASS BEGINS TO MODERATE WITH ABOVE NORMAL
TEMPS RETURNING BY THIS WEEKEND. WHILE WE GET A REPRIEVE FROM
WINDY CONDITIONS FRIDAY...LATEST GUIDANCE IS INDICATING ANOTHER
QUICK MOVING SHORTWAVE TROUGH OVER THE NORTHERN PLAINS WHICH COULD
BRING ADVISORY LEVEL WINDS (GUSTS 45MPH+) TO OUR CWA. WILL NEED TO
MONITOR.
.LONG TERM...(SUNDAY THROUGH WEDNESDAY)
ISSUED AT 308 AM MST THU JAN 16 2014
NEXT WEEK LOOKS SIMILAR TO THIS WEEK WITH MILD TEMPS AND A
PERSISTENT NORTHWEST WIND. NO MEASURABLE PRECIP IN SIGHT GIVEN THE
CURRENT PATTERN. AT THE SYNOPTIC SCALE A RIDGE CONTINUES TO DOMINATE
THE WESTERN CONUS AND A BROAD TROUGH ACROSS THE EAST. THE ONLY
NOTICEABLE SYNOPTIC FEATURE FOR THE CENTRAL PLAINS WILL BE A SHOT OF
COLD AIR ARRIVING LATE MONDAY INTO TUESDAY. LOCALLY THE FRONT
ASSOCIATED WITH THIS COLD AIR WILL NOT BE ESPECIALLY STRONG AS THE
BEST FORCING WILL BE FARTHER EAST.
SENSIBLE WX BENIGN FOR THE PERIOD. MILD ON SUNDAY WITH A SURFACE
TROUGH SETTING UP ACROSS EASTERN COLORADO AND WEST TO SOUTHWEST
WINDS AT THE SURFACE AND ALOFT. ECMWF HAS BEEN CONSISTENT WITH 850MB
TEMPS IN THE LOWER TEENS AND FULL SUNSHINE WILL LEAD TO HIGHS IN THE
LOW 60S...POSSIBLY APPROACHING THE RECORD HIGHS AT MCK AND HLC
WHICH ARE ONLY 66. GEM IS SIMILAR...BUT GFS IS NOT AS WARM. A WEAK
SHORTWAVE TROUGH AND ASSOCIATED FRONT WILL MOVE THROUGH MID TO LATE
SUNDAY SHIFTING WINDS TO THE NORTH AND BRINGING MORE SEASONABLE AIR
FOR THE START OF THE WORK WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 422 AM MST THU JAN 16 2014
FRONT IS CURRENTLY MOVING ACROSS BOTH TAF SITES WITH WINDS ALREADY
GUSTING OUT OF THE NW 25-30KT. AS AN UPPER LEVEL DISTURBANCE MOVES
EAST STRONG PRESSURE GRADIENT WILL SUPPORT VERY WINDY CONDITIONS AT
BOTH TAF SITES BY LATE MORNING. GUSTS AROUND 55KT AT BOTH TAF
SITES SHOULD LEAD TO REDUCED VISIBILITIES DUE TO BLOWING
DUST...WITH MVFR VIS (5SM) LIKELY BY MIDDAY. COULD SEE VISIBILITIES
ACTUALLY APPROACH 1/2SM OR LESS AT TIMES. CONFIDENCE WAS TOO LOW
TO GO THAT LOW UNTIL WE SEE HOW THIS EVENT UNFOLDS...SO I KEPT
TEMPO 1SM GROUP FOR AFTERNOON PERIOD. CONDITIONS WILL QUICKLY
IMPROVE AROUND SUNSET...THOUGH GUSTS TO 30KT WILL STILL BE
POSSIBLE THROUGH THE EVENING HOURS.
&&
.FIRE WEATHER...
ISSUED AT 302 AM MST THU JAN 16 2014
REGARDING RFW CONDITIONS...WITH VERY STRONG WINDS AND VERY DRY/CURED
FUELS THERE IS A CONCERN FOR DANGEROUS FIRE CONDITIONS. THE ONE
CAVEAT IS RH VALUES RIGHT AT 20 PERCENT ACROSS MOST OF THE AREA AND
APPROACHING 40 PERCENT IN THE WEST TODAY. WHILE THESE RH VALUES ARE
CERTAINLY MARGINAL IN THE WEST...AFTER PREVIOUSLY COORDINATING
WITH PARTNERS IT WAS DECIDED TO COVER OUR ENTIRE AREA WITH AN
RFW DURING THE EVENING SHIFT...AND I SEE NO REASON TO MAKE A CHANGE
CONSIDERING THE IMPACT OF THE WINDS ON THE ALREADY CURED FUELS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...HIGH WIND WARNING UNTIL 7 PM MST /8 PM CST/ THIS EVENING FOR
KSZ001>004-013>016-027>029-042.
RED FLAG WARNING FROM 10 AM MST /11 AM CST/ THIS MORNING TO 5 PM
MST /6 PM CST/ THIS AFTERNOON FOR KSZ001>004-013>016-
027>029-041-042.
WIND ADVISORY UNTIL 7 PM MST THIS EVENING FOR KSZ041.
CO...HIGH WIND WARNING UNTIL 7 PM MST THIS EVENING FOR COZ090-091.
RED FLAG WARNING FROM 10 AM THIS MORNING TO 5 PM MST THIS
AFTERNOON FOR COZ252>254.
WIND ADVISORY UNTIL 7 PM MST THIS EVENING FOR COZ092.
NE...HIGH WIND WARNING UNTIL 7 PM MST /8 PM CST/ THIS EVENING FOR
NEZ079>081.
RED FLAG WARNING FROM 10 AM MST /11 AM CST/ THIS MORNING TO 5 PM
MST /6 PM CST/ THIS AFTERNOON FOR NEZ079>081.
&&
$$
SHORT TERM...DR
LONG TERM...JJM
AVIATION...DR
FIRE WEATHER...DR
AREA FORECAST DISCUSSION
NWS TOPEKA KS
412 AM CST Thu Jan 16 2014
.SHORT TERM...(Today and Tonight)
Issued at 317 AM CST THU JAN 16 2014
Mid level shortwave and associated vorticity was located over IA and
NE around 09Z and will continue to dig southward through out the day
today. This wave is pushing a surface cold front southward which is
currently located across portions of southeast and south central NE.
Winds ahead of the front are light out of the west although directly
behind the front become northwesterly and increase rapidly. Forecast
soundings continue to show that the boundary will mix into 50-60 kts
winds as early as 10 am lasting through most of the afternoon. There
are a few factors that could limit the momentum transfer of the wind
today which include weak subsidence and stratus within the mixing
layer. The stratus should remain confined to far northeast KS during
the afternoon hours while partly cloudy elsewhere. The last few runs
of the RAP and HRRR continue to agree that most areas along and
north of interstate 35 will experience surface gusts around 35-45
kts and approaching 50 kts in the far northwest portion of the
forecast area. Therefore have upgraded the advisory to a high wind
warning in that location. The strongest wind gusts should subside
around sunset this evening although will remain gusty through most
of the night. High temperatures today are generally in the 40s
although look to occur mostly before noon. There is a slight chance
for sprinkles and or flurries in far northeast KS during the
afternoon and evening as a vort max rotates through the trough axis.
During the afternoon cold air advection increases sending
temperatures into the mid to upper 10s by Friday
morning.
.LONG TERM...(Friday through Wednesday)
Issued at 317 AM CST THU JAN 16 2014
A longer wave-length upper level trough will continue across the
east central conus with a longer wave-length upper level ridge
along the the western coast of North America through the forecast
period.
The amplified upper level trough across the eastern conus will move
east into the mid Atlantic states on Sunday. A secondary upper level
trough will dig southeast across the Great Lakes States into the Mid
Atlantic States on Sunday.
Friday and Friday night, a surface ridge of high pressure will shift
southeast of the CWA by late afternoon. Northwest winds will
diminish during the early afternoon hours and become southerly
across north central KS. Highs Friday will only reach the lower to
mid 30s across northeast and east central KS, with lower 40s across
north central KS. Lows Friday night will drop into the 20s, shortly
after midnight with temperatures remaining steady or lowly rising
through the morning hours of Saturday.
Saturday, as the H5 trough digs southeast across the Great Lakes a weak
cold front will push southward across the CWA during the afternoon
hours. Highs ahead of the front should warm into the upper 40s to
around 50 degrees across much of the CWA. Temperatures across the
northern counties could slowly fall through the 40s during the mid
and late afternoon hours as winds shift from the west-southwest to
the northwest.
Sunday, The upper flow will become more zonal as a lee surface
trough deepens across western KS and southeast CO. Southwest surface
winds will advect warmer downslope air northeast across central
and eastern KS. Highs will warm into the mid 50s to around 60
degrees with mostly sunny skies.
Another upper level trough will dig southeast out west central
Canada and across the northern plains, and into the mid MS river
valley and OH river valley. This will bring a surge of colder air
southward across the northern plains into eastern KS. Highs on
Monday will cool into the mid 40s to around 50 and down into the
30s to around 40 on Tuesday.
&&
.AVIATION...(For the 06Z TAFs through 06Z Thursday Night)
Issued at 1134 PM CST WED JAN 15 2014
For the 06z TAFs, VFR conditions are expected through the period. A
warm front was passing through the region with winds gradually
veering from south to northwest. Before the surface winds begin to
increase behind the front, there is the potential for a couple of
hours of llws as winds near 1500-2000ft start to reach near 50kts.
Surface winds are expected to quickly increase after sunrise and
remain very breezy through the day and even through the evening
hours. During the afternoon hours there is a good potential for the
TAF sites to reach sustained winds near 30kts and gusts upwards of
40kts and possibly even higher.
&&
.FIRE WEATHER...
Issued at 317 AM CST THU JAN 16 2014
Very high rangeland fire danger criteria will be met across much of
north central, northeast and east central KS this Afternoon. Minimum
RH`s will drop to 25 to 35 percent along with very strong
northwest winds of 30 to 40 MPH with gusts of 40 to 55 MPH, even
some 60 MPH wind gusts across Republic and Cloud counties. Given
the strong northwest winds and dry fuels, any outdoor burning will
lead to uncontrollable wild fires late this morning and through
the afternoon hours. All planned outdoor burning Today will need
to be rescheduled.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY from 10 AM this morning to 7 PM CST this evening
FOR KSZ009>012-021>024-026-034>040-054-055.
HIGH WIND WARNING from 10 AM this morning to 7 PM CST this
evening FOR KSZ008-020.
&&
$$
SHORT TERM...Sanders
LONG TERM...Gargan
AVIATION...Hennecke
FIRE WEATHER...Gargan
AREA FORECAST DISCUSSION
NWS GOODLAND KS
308 AM MST THU JAN 16 2014
.SHORT TERM...(TODAY THROUGH SATURDAY NIGHT)
ISSUED AT 308 AM MST THU JAN 16 2014
LATEST WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOWS AT THE 500MB
LEVEL STRONG 585DM RIDGE OVER THE EASTERN PACIFIC WITH EASTERN
FLANK EXTENDING TO GREAT BASIN...AND 511DM CLOSED LOW CENTERED
NORTH OF THE GREAT LAKES REGION IN CANADA. BETWEEN THESE FEATURES
DEEP SURFACE-300MB UNIDIRECTIONAL GRADIENT HAS DEVELOPED ACROSS
THE PLAINS. UPSTREAM VWP WOULD INDICATE A 75+ JET AT 700MB AND
95+JET AT 500MB ALREADY OVER NORTHERN NEBRASKA. A STRONG PV15
HEIGHT ANOMALY IS CURRENTLY OVER NORTHERN NEBRASKA IN LINE WITH A
SHORTWAVE TROUGH AXIS ROUNDING THE WESTERN FLANK OF THE LARGE
SCALE TROUGH. STRONG SUBSIDENCE NORTH OF THIS FEATURE IS EVIDENT
BY MID LEVEL DRYING ON WV IMAGERY WHICH EXTENDS ACROSS THE WESTERN
DAKOTAS/EASTERN MONTANA. EAST OF THIS IS A PLUME MOISTURE ON WV
IMAGERY EXTENDING FROM THE CANADIAN ROCKIES ACROSS EASTERN MONTANA
ASSOCIATED WITH CIRRUS DECK.
AXIS OF MID-HIGH CLOUDS EXPECTED TO MOVE SOUTH OVER CWA AS FRONT
QUICKLY MOVES SOUTH THIS MORNING...WITH MOUNTAIN WAVE CIRRUS
POSSIBLY MOVING THROUGH ACROSS SW CWA DURING THE DAY. AREA OF
STRONG SUBSIDENCE ON WV IMAGERY SHOULD MOVE SOUTH OVER OUR
CWA...SUPPORTING GOOD DOWNWARD MOTION AND CLEARING IN THE EAST.
HIGH CLOUDS COULD HAVE IMPACT ON MIXING POTENTIAL TODAY IN THE
WEST...HOWEVER MODEL SOUNDINGS CONTINUE TO INDICATE VERY DRY
MOISTURE PROFILES ACROSS THE CWA...AND CURRENT ORIENTATION OF
MOISTURE PLUME ON WV MATCHING H5-H3 MODEL RH WOULD INDICATE
CIRRUS MAINLY IMPACTING OUR FAR WEST/SW WHERE MODEL WINDS ARE
ALREADY LIGHTER.
LATEST RAP HAS COME IN STRONGER WITH WIND AT TOP OF MIXED LAYER
OVER CHEYENNE COUNTY COLORADO AND GREELEY KS NEAR 50KT. ALL
OTHER GUIDANCE IS LOWER WITH VALUES IN THE 35-45KT RANGE...AND
LATEST HRRR WIND GUST FIELD KEEPS GUSTS SUB WARNING OVER THESE
COUNTIES. WITH CONCERN ALREADY REGARDING CLOUDS I THINK THE
ONGOING WIND ADVISORY COVERS POTENTIAL GUSTS FOR THESE TWO
COUNTIES..
TOP OF MIXED LAYER ON ALL GUIDANCE ACROSS REST OF CWA IS IN THE
800-780MB LAYER AND STILL SUPPORTS WIND GUSTS IN THE 50-55KT RANGE.
ALL MODELS SHOW MUCH STRONGER WINDS IN THE 60KT+ RANGE (MATCH
TRENDS ON UPSTREAM VWP)...AND IF THESE STRONGER WINDS WERE TO
MIX DOWN WE COULD SEE WINDS AS HIGH AS 80MPH. BASED ON CURRENT
MODEL MIXING HEIGHTS THIS IS NOT ANTICIPATED...BUT IT IS WORTH
MONITORING FOR POSSIBLE DAYTIME UPDATES.
FRIDAY-SATURDAY...AIR MASS BEGINS TO MODERATE WITH ABOVE NORMAL
TEMPS RETURNING BY THIS WEEKEND. WHILE WE GET A REPRIEVE FROM
WINDY CONDITIONS FRIDAY...LATEST GUIDANCE IS INDICATING ANOTHER
QUICK MOVING SHORTWAVE TROUGH OVER THE NORTHERN PLAINS WHICH COULD
BRING ADVISORY LEVEL WINDS (GUSTS 45MPH+) TO OUR CWA. WILL NEED TO
MONITOR.
.LONG TERM...(SUNDAY THROUGH WEDNESDAY)
ISSUED AT 308 AM MST THU JAN 16 2014
NEXT WEEK LOOKS SIMILAR TO THIS WEEK WITH MILD TEMPS AND A
PERSISTENT NORTHWEST WIND. NO MEASURABLE PRECIP IN SIGHT GIVEN THE
CURRENT PATTERN. AT THE SYNOPTIC SCALE A RIDGE CONTINUES TO DOMINATE
THE WESTERN CONUS AND A BROAD TROUGH ACROSS THE EAST. THE ONLY
NOTICEABLE SYNOPTIC FEATURE FOR THE CENTRAL PLAINS WILL BE A SHOT OF
COLD AIR ARRIVING LATE MONDAY INTO TUESDAY. LOCALLY THE FRONT
ASSOCIATED WITH THIS COLD AIR WILL NOT BE ESPECIALLY STRONG AS THE
BEST FORCING WILL BE FARTHER EAST.
SENSIBLE WX BENIGN FOR THE PERIOD. MILD ON SUNDAY WITH A SURFACE
TROUGH SETTING UP ACROSS EASTERN COLORADO AND WEST TO SOUTHWEST
WINDS AT THE SURFACE AND ALOFT. ECMWF HAS BEEN CONSISTENT WITH 850MB
TEMPS IN THE LOWER TEENS AND FULL SUNSHINE WILL LEAD TO HIGHS IN THE
LOW 60S...POSSIBLY APPROACHING THE RECORD HIGHS AT MCK AND HLC
WHICH ARE ONLY 66. GEM IS SIMILAR...BUT GFS IS NOT AS WARM. A WEAK
SHORTWAVE TROUGH AND ASSOCIATED FRONT WILL MOVE THROUGH MID TO LATE
SUNDAY SHIFTING WINDS TO THE NORTH AND BRINGING MORE SEASONABLE AIR
FOR THE START OF THE WORK WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 926 PM MST WED JAN 15 2014
VFR CONDITIONS FOR MOST OF THE TAF PERIOD...WITH THE IFR TO MVFR
VISIBILITY STILL POSSIBLE TOMORROW WITH THE BLOWING DUST. AS THE
UPPER TROUGH PUSHES SOUTH AND A STRONG JET STREAK MOVES OVER THE
TAF SITES...NORTHWEST WINDS WILL INCREASE TOMORROW MID-DAY.
MODELS ARE STILL HOLDING ONTO THE MIXING LAYER HEIGHT IN A 55 TO
60 KT JET SO HAVE KEPT GUSTS AT KGLD AT 52 KTS STARTING AT 17Z AND
GUSTS AT KMCK AT 55 KTS STARTING AT 16Z. THE TEMPO GROUP STILL
ACCOUNTS FOR POSSIBLE VISIBILITY REDUCTIONS DUE TO THE BLOWING
DUST...HAVE VISIBILITY DOWN TO 1SM FOR KGLD AND 2SM FOR KMCK.
VISIBILITY IS LIKELY TO BE REDUCED IN LATER TAF ISSUANCES AS WINDS
BEGIN TO INCREASE AND THE EVENT UNFOLDS. NORTHWEST WINDS SHOULD
BEGIN TO DECLINE AROUND SUNSET...WITH GUSTS AROUND 24 KTS AT KMCK
AND 27 KTS AT KGLD AROUND 0Z/01Z. WINDS WILL CONTINUE TO DECREASE
AS THE NIGHT PROGRESSES.
&&
.FIRE WEATHER...
ISSUED AT 302 AM MST THU JAN 16 2014
REGARDING RFW CONDITIONS...WITH VERY STRONG WINDS AND VERY DRY/CURED
FUELS THERE IS A CONCERN FOR DANGEROUS FIRE CONDITIONS. THE ONE
CAVEAT IS RH VALUES RIGHT AT 20 PERCENT ACROSS MOST OF THE AREA AND
APPROACHING 40 PERCENT IN THE WEST TODAY. WHILE THESE RH VALUES ARE
CERTAINLY MARGINAL IN THE WEST...AFTER PREVIOUSLY COORDINATING
WITH PARTNERS IT WAS DECIDED TO COVER OUR ENTIRE AREA WITH AN
RFW DURING THE EVENING SHIFT...AND I SEE NO REASON TO MAKE A CHANGE
CONSIDERING THE IMPACT OF THE WINDS ON THE ALREADY CURED FUELS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...HIGH WIND WARNING FROM 7 AM MST /8 AM CST/ THIS MORNING TO 7 PM
MST /8 PM CST/ THIS EVENING FOR KSZ001>004-013>016-027>029-
042.
RED FLAG WARNING FROM 10 AM MST /11 AM CST/ THIS MORNING TO 5 PM
MST /6 PM CST/ THIS AFTERNOON FOR KSZ001>004-013>016-
027>029-041-042.
WIND ADVISORY FROM 7 AM THIS MORNING TO 7 PM MST THIS EVENING
FOR KSZ041.
CO...HIGH WIND WARNING FROM 7 AM THIS MORNING TO 7 PM MST THIS
EVENING FOR COZ090-091.
RED FLAG WARNING FROM 10 AM THIS MORNING TO 5 PM MST THIS
AFTERNOON FOR COZ252>254.
WIND ADVISORY FROM 7 AM THIS MORNING TO 7 PM MST THIS EVENING
FOR COZ092.
NE...HIGH WIND WARNING FROM 7 AM MST /8 AM CST/ THIS MORNING TO 7 PM
MST /8 PM CST/ THIS EVENING FOR NEZ079>081.
RED FLAG WARNING FROM 10 AM MST /11 AM CST/ THIS MORNING TO 5 PM
MST /6 PM CST/ THIS AFTERNOON FOR NEZ079>081.
&&
$$
SHORT TERM...DR
LONG TERM...JJM
AVIATION...ALW/RRH
FIRE WEATHER...DR
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
1202 PM EST Thu Jan 16 2014
...Updated Aviation Discussion...
...Forecast Update...
Issued at 1040 AM EST Thu Jan 16 2014
Light snow has been falling across portions of southern Indiana and
west central Kentucky this morning. Area webcams show any
accumulations are mainly on sidewalks and grassy surfaces, though
there have been some reports of slick roads under the heaviest
bursts of snow. All in all, accumulations should be fairly light
through the day with a dusting to up to an inch of snow possible. Am
a bit unsure about how much of this precipitation will change over
to rain this afternoon as temperatures are difficult. Extensive
cloud cover and precipitation will be offset by strong southerly
winds. In general, trended temps down a few degrees this afternoon.
Also went ahead and issued a Special Weather Statement for south and
east central Kentucky discussing the possibility of snow
accumulations tonight and tomorrow.
Issued at 625 AM EST Thu Jan 16 2014
Forecast this morning looks largely on track. Latest radar imagery
looks a bit more menacing than reality, as it appears it`s taking
awhile for the low-levels to saturate enough to get precip to the
ground. The best band of snow so far has been in and around the STL
metro, where there have been a few reports of accumulations near an
inch. The latest RAP and HRRR have a pretty good handle on this
band of snow, and actually weaken it substantially as it heads into
the LMK CWA this morning. Looking at the last few frames of the
radar mosaic, this appears to already be occurring. The HRRR does
however develop additional precipitation behind this initial batch
for this afternoon, which may be more of a rain/snow mix along the
Ohio River, with more snow possible in southern Indiana. All in
all, amounts of up to an inch still look good across southern
Indiana, with up to a few tenths of an inch possible along the Ohio
River.
.SHORT TERM (Now through Friday)...
Issued at 305 AM EST Thu Jan 16 2014
...Light snow accumulations possible today through Friday...
The synoptic pattern this afternoon features a broad, deep trough
across the eastern 2/3rds of the CONUS, thanks to an amplified,
blocking ridge across the eastern Pacific. Multiple disturbances
will drop through this trough aloft this period, bringing a few
chances for precipitation.
Current water vapor imagery depicts the first quick-hitting
shortwave trough diving southeast through portions of Iowa this
morning. Ascent ahead of this feature has led to a band of snow
across MO and IL. Surface observations show much of this snow not
hitting the ground, likely due to a rather dry sub-cloud layer.
However, the band appears to have intensified a bit (Quincy, IL now
down to 2SM in light snow) over the past hour, and expect a slow
strengthening trend to continue through the morning hours. This
band will approach southern IN by morning, spreading into northern
KY by late morning.
One complicating factor to the forecast today will be the brisk
southwesterly winds, which will likely push temperatures above
freezing in most locations. However, forecast soundings depict
rather dry low-level air, which will keep wet bulb temperatures
below freezing for much of northern KY and southern IN through the
afternoon. Therefore, despite surface temperatures creeping above
freezing, think precip will fall as mostly snow through noon. By
early afternoon, enough warm air may work in to change the precip
over to a rain/snow mix for areas along the Ohio River, but southern
IN will likely remain snow throughout much of the event.
South-central KY will not see much precipitation at all today, but
anything that does fall will likely just be light rain/drizzle. Any
snow accumulations will be confined to areas along and north of
I-64. Up to an inch may be possible across far northern Dubois,
Orange, Washington, Scott, and Jefferson IN counties, tapering to
only a tenth or two further south in areas along the Ohio River
(including the Louisville metro). Will be issuing an SPS to
highlight these possible light accumulations.
A surface cold front will push through the region tonight, bringing
an end to the "warmer" temperatures as cooler air quickly pushes
in. Forecast soundings show lapse rates quickly steepening, which
will support convective snow showers overnight. Typically, these
type of showers tend to thrive more in the daylight hours given
better available instability. Hi-res guidance remains split on just
how widespread these showers will be overnight, leading to a low
confidence forecast with respect to coverage. Given the low-level
profiles coupled with the forcing from the upper-level trough axis
swinging through, think 30-40 pops seem reasonable overnight,
increasing to 40-50 by the daylight hours Friday. The best coverage
will likely be late Friday morning/early afternoon across the
Northern Bluegrass and the Cumberland region, due to upslope flow
and the trough axis swinging through at a more favorable time of
day. As is typical in these scenarios, snowfall amounts will be
quite variable. Some locations could receive amounts in excess of
an inch, while others see nothing. These showers could be moving
through during the morning commute, so there may be some negative
impacts from these snow showers Friday morning. These impacts,
coupled with possible amounts in excess of an inch in some
locations, may warrant a Winter Weather Advisory in coming forecasts
once confidence in timing/coverage/intensity increases.
After highs in the upper 30s and lower 40s today, the passing cold
front will drop readings into the low and mid 20s tonight.
Temperatures will not recover much at all on Friday due to the
strong cold air advection, remaining in the low to mid 20s. By
Friday afternoon/evening, wind chills will be in the upper single
digits to lower teens!
.LONG TERM (Friday Night through Wednesday)...
Issued at 300 AM EST Thu Jan 16 2014
The long term will be characterized by general troughing over the
eastern CONUS and ridging over the west. Multiple shortwaves will
dive through this northwesterly flow and reinforce the trough and
bring chances for snow showers to the region. Confidence is fairly
high that temperatures will run mostly below normal, but there is
much more uncertainty in the timing of any disturbances and
associated snow chances, as well as the magnitude of the temp
departures.
A fairly vigorous Clipper will dive SE into the upper Ohio Valley
late on Saturday, with snow chances in our north and east.
Tremendous bust potential with Sat afternoon max temps, as the GFS
MOS seems to reflect stronger warm advection into west-central KY
resulting in temps nearly 10 degrees warmer than any other guidance.
Have stayed with raw model consensus, which ranges from lower 30s
over the Bluegrass to upper 30s near BWG. Light accumulations
possible Sat night, especially toward the Bluegrass region.
Dry weather and moderating temps Sunday into Monday as heights rise
and a flatter pattern aloft directs the Clippers more across the
Great Lakes. The pattern becomes more amplified toward the middle of
the week, as the cold air is reinforced again. Not confident enough
to include POPs this far out. Temps will trend colder than the
previous forecast, but not as cold as the latest extended GFS MOS,
which is about 10 degrees colder than previous runs for Wed-Thu.
ECMWF is progressive enough that the core of the cold air never
quite settles into the Ohio Valley. Lows in the teens and highs in
the 20s seem to be a safe bet, but it remains to be seen whether we
will be on the higher end or the lower end of that range.
&&
.AVIATION (18Z TAF Update)...
Updated at 1200 PM EST Thu Jan 16 2014
Light snow continues to move across the area this afternoon and will
mainly affect SDF and LEX. Visibilities at SDF will bounce between
MVFR and IFR over the next few hours before this batch of light snow
moves out. This is weakening as it moves east, so reductions to IFR
visibility at LEX are less certain this afternoon. Winds today will
continue to be out of the south with gusts to 20 knots at times.
Winds will shift to westerly tonight as a cold front crosses the
area. They will again become gusty during the morning hours
tomorrow. An upper level disturbance crossing the area late tonight
into tomorrow will bring another round of snow showers which will
reduce visibilities and ceilings. However, timing of the heavier
bands is rather uncertain at this time.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Update.........EER/KJD
Short Term.....KJD
Long Term......RAS
Aviation.......EER
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
1042 AM EST Thu Jan 16 2014
...Forecast Update...
Issued at 1040 AM EST Thu Jan 16 2014
Light snow has been falling across portions of southern Indiana and
west central Kentucky this morning. Area webcams show any
accumulations are mainly on sidewalks and grassy surfaces, though
there have been some reports of slick roads under the heaviest
bursts of snow. All in all, accumulations should be fairly light
through the day with a dusting to up to an inch of snow possible. Am
a bit unsure about how much of this precipitation will change over
to rain this afternoon as temperatures are difficult. Extensive
cloud cover and precipitation will be offset by strong southerly
winds. In general, trended temps down a few degrees this afternoon.
Also went ahead and issued a Special Weather Statement for south and
east central Kentucky discussing the possibility of snow
accumulations tonight and tomorrow.
Issued at 625 AM EST Thu Jan 16 2014
Forecast this morning looks largely on track. Latest radar imagery
looks a bit more menacing than reality, as it appears it`s taking
awhile for the low-levels to saturate enough to get precip to the
ground. The best band of snow so far has been in and around the STL
metro, where there have been a few reports of accumulations near an
inch. The latest RAP and HRRR have a pretty good handle on this
band of snow, and actually weaken it substantially as it heads into
the LMK CWA this morning. Looking at the last few frames of the
radar mosaic, this appears to already be occurring. The HRRR does
however develop additional precipitation behind this initial batch
for this afternoon, which may be more of a rain/snow mix along the
Ohio River, with more snow possible in southern Indiana. All in
all, amounts of up to an inch still look good across southern
Indiana, with up to a few tenths of an inch possible along the Ohio
River.
.SHORT TERM (Now through Friday)...
Issued at 305 AM EST Thu Jan 16 2014
...Light snow accumulations possible today through Friday...
The synoptic pattern this afternoon features a broad, deep trough
across the eastern 2/3rds of the CONUS, thanks to an amplified,
blocking ridge across the eastern Pacific. Multiple disturbances
will drop through this trough aloft this period, bringing a few
chances for precipitation.
Current water vapor imagery depicts the first quick-hitting
shortwave trough diving southeast through portions of Iowa this
morning. Ascent ahead of this feature has led to a band of snow
across MO and IL. Surface observations show much of this snow not
hitting the ground, likely due to a rather dry sub-cloud layer.
However, the band appears to have intensified a bit (Quincy, IL now
down to 2SM in light snow) over the past hour, and expect a slow
strengthening trend to continue through the morning hours. This
band will approach southern IN by morning, spreading into northern
KY by late morning.
One complicating factor to the forecast today will be the brisk
southwesterly winds, which will likely push temperatures above
freezing in most locations. However, forecast soundings depict
rather dry low-level air, which will keep wet bulb temperatures
below freezing for much of northern KY and southern IN through the
afternoon. Therefore, despite surface temperatures creeping above
freezing, think precip will fall as mostly snow through noon. By
early afternoon, enough warm air may work in to change the precip
over to a rain/snow mix for areas along the Ohio River, but southern
IN will likely remain snow throughout much of the event.
South-central KY will not see much precipitation at all today, but
anything that does fall will likely just be light rain/drizzle. Any
snow accumulations will be confined to areas along and north of
I-64. Up to an inch may be possible across far northern Dubois,
Orange, Washington, Scott, and Jefferson IN counties, tapering to
only a tenth or two further south in areas along the Ohio River
(including the Louisville metro). Will be issuing an SPS to
highlight these possible light accumulations.
A surface cold front will push through the region tonight, bringing
an end to the "warmer" temperatures as cooler air quickly pushes
in. Forecast soundings show lapse rates quickly steepening, which
will support convective snow showers overnight. Typically, these
type of showers tend to thrive more in the daylight hours given
better available instability. Hi-res guidance remains split on just
how widespread these showers will be overnight, leading to a low
confidence forecast with respect to coverage. Given the low-level
profiles coupled with the forcing from the upper-level trough axis
swinging through, think 30-40 pops seem reasonable overnight,
increasing to 40-50 by the daylight hours Friday. The best coverage
will likely be late Friday morning/early afternoon across the
Northern Bluegrass and the Cumberland region, due to upslope flow
and the trough axis swinging through at a more favorable time of
day. As is typical in these scenarios, snowfall amounts will be
quite variable. Some locations could receive amounts in excess of
an inch, while others see nothing. These showers could be moving
through during the morning commute, so there may be some negative
impacts from these snow showers Friday morning. These impacts,
coupled with possible amounts in excess of an inch in some
locations, may warrant a Winter Weather Advisory in coming forecasts
once confidence in timing/coverage/intensity increases.
After highs in the upper 30s and lower 40s today, the passing cold
front will drop readings into the low and mid 20s tonight.
Temperatures will not recover much at all on Friday due to the
strong cold air advection, remaining in the low to mid 20s. By
Friday afternoon/evening, wind chills will be in the upper single
digits to lower teens!
.LONG TERM (Friday Night through Wednesday)...
Issued at 300 AM EST Thu Jan 16 2014
The long term will be characterized by general troughing over the
eastern CONUS and ridging over the west. Multiple shortwaves will
dive through this northwesterly flow and reinforce the trough and
bring chances for snow showers to the region. Confidence is fairly
high that temperatures will run mostly below normal, but there is
much more uncertainty in the timing of any disturbances and
associated snow chances, as well as the magnitude of the temp
departures.
A fairly vigorous Clipper will dive SE into the upper Ohio Valley
late on Saturday, with snow chances in our north and east.
Tremendous bust potential with Sat afternoon max temps, as the GFS
MOS seems to reflect stronger warm advection into west-central KY
resulting in temps nearly 10 degrees warmer than any other guidance.
Have stayed with raw model consensus, which ranges from lower 30s
over the Bluegrass to upper 30s near BWG. Light accumulations
possible Sat night, especially toward the Bluegrass region.
Dry weather and moderating temps Sunday into Monday as heights rise
and a flatter pattern aloft directs the Clippers more across the
Great Lakes. The pattern becomes more amplified toward the middle of
the week, as the cold air is reinforced again. Not confident enough
to include POPs this far out. Temps will trend colder than the
previous forecast, but not as cold as the latest extended GFS MOS,
which is about 10 degrees colder than previous runs for Wed-Thu.
ECMWF is progressive enough that the core of the cold air never
quite settles into the Ohio Valley. Lows in the teens and highs in
the 20s seem to be a safe bet, but it remains to be seen whether we
will be on the higher end or the lower end of that range.
&&
.AVIATION (12Z TAF Update)...
Updated at 600 AM EST Thu Jan 16 2014
An area of low pressure will move into the Ohio Valley today. Out
ahead of this system, southwest winds will increase to 15 to 20
knots, with gusts to around 25 knots. Precipitation will move
mainly into KSDF late this morning, initially falling as light
snow. This snow may just be heavy enough to reduce cigs/vsbys to
MVFR thresholds for a few hours. However, precipitation will begin
to mix with rain and decrease in intensity by the mid to late
afternoon, bringing conditions back up into VFR thresholds. At KLEX
and KBWG, a stray shower or two is possible, but do not expect many
impacts to operations from today`s system, other than the increasing
winds.
A cold front will push through all sites tonight. Scattered snow
showers will develop, which may be moderate to locally heavy at
times overnight into Friday morning. Will continue to handle with
VCSH wording for now, but cigs/vsbys within these showers may
briefly be reduced to MVFR or even IFR thresholds while dropping
quick, light accumulations.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Update.........EER/KJD
Short Term.....KJD
Long Term......RAS
Aviation.......KJD
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
625 AM EST Thu Jan 16 2014
...Forecast Update...
Issued at 625 AM EST Thu Jan 16 2014
Forecast this morning looks largely on track. Latest radar imagery
looks a bit more menacing than reality, as it appears it`s taking
awhile for the low-levels to saturate enough to get precip to the
ground. The best band of snow so far has been in and around the STL
metro, where there have been a few reports of accumulations near an
inch. The latest RAP and HRRR have a pretty good handle on this
band of snow, and actually weaken it substantially as it heads into
the LMK CWA this morning. Looking at the last few frames of the
radar mosaic, this appears to already be occurring. The HRRR does
however develop additional precipitation behind this initial batch
for this afternoon, which may be more of a rain/snow mix along the
Ohio River, with more snow possible in southern Indiana. All in
all, amounts of up to an inch still look good across southern
Indiana, with up to a few tenths of an inch possible along the Ohio
River.
.SHORT TERM (Now through Friday)...
Issued at 305 AM EST Thu Jan 16 2014
...Light snow accumulations possible today through Friday...
The synoptic pattern this afternoon features a broad, deep trough
across the eastern 2/3rds of the CONUS, thanks to an amplified,
blocking ridge across the eastern Pacific. Multiple disturbances
will drop through this trough aloft this period, bringing a few
chances for precipitation.
Current water vapor imagery depicts the first quick-hitting
shortwave trough diving southeast through portions of Iowa this
morning. Ascent ahead of this feature has led to a band of snow
across MO and IL. Surface observations show much of this snow not
hitting the ground, likely due to a rather dry sub-cloud layer.
However, the band appears to have intensified a bit (Quincy, IL now
down to 2SM in light snow) over the past hour, and expect a slow
strengthening trend to continue through the morning hours. This
band will approach southern IN by morning, spreading into northern
KY by late morning.
One complicating factor to the forecast today will be the brisk
southwesterly winds, which will likely push temperatures above
freezing in most locations. However, forecast soundings depict
rather dry low-level air, which will keep wet bulb temperatures
below freezing for much of northern KY and southern IN through the
afternoon. Therefore, despite surface temperatures creeping above
freezing, think precip will fall as mostly snow through noon. By
early afternoon, enough warm air may work in to change the precip
over to a rain/snow mix for areas along the Ohio River, but southern
IN will likely remain snow throughout much of the event.
South-central KY will not see much precipitation at all today, but
anything that does fall will likely just be light rain/drizzle. Any
snow accumulations will be confined to areas along and north of
I-64. Up to an inch may be possible across far northern Dubois,
Orange, Washington, Scott, and Jefferson IN counties, tapering to
only a tenth or two further south in areas along the Ohio River
(including the Louisville metro). Will be issuing an SPS to
highlight these possible light accumulations.
A surface cold front will push through the region tonight, bringing
an end to the "warmer" temperatures as cooler air quickly pushes
in. Forecast soundings show lapse rates quickly steepening, which
will support convective snow showers overnight. Typically, these
type of showers tend to thrive more in the daylight hours given
better available instability. Hi-res guidance remains split on just
how widespread these showers will be overnight, leading to a low
confidence forecast with respect to coverage. Given the low-level
profiles coupled with the forcing from the upper-level trough axis
swinging through, think 30-40 pops seem reasonable overnight,
increasing to 40-50 by the daylight hours Friday. The best coverage
will likely be late Friday morning/early afternoon across the
Northern Bluegrass and the Cumberland region, due to upslope flow
and the trough axis swinging through at a more favorable time of
day. As is typical in these scenarios, snowfall amounts will be
quite variable. Some locations could receive amounts in excess of
an inch, while others see nothing. These showers could be moving
through during the morning commute, so there may be some negative
impacts from these snow showers Friday morning. These impacts,
coupled with possible amounts in excess of an inch in some
locations, may warrant a Winter Weather Advisory in coming forecasts
once confidence in timing/coverage/intensity increases.
After highs in the upper 30s and lower 40s today, the passing cold
front will drop readings into the low and mid 20s tonight.
Temperatures will not recover much at all on Friday due to the
strong cold air advection, remaining in the low to mid 20s. By
Friday afternoon/evening, wind chills will be in the upper single
digits to lower teens!
.LONG TERM (Friday Night through Wednesday)...
Issued at 300 AM EST Thu Jan 16 2014
The long term will be characterized by general troughing over the
eastern CONUS and ridging over the west. Multiple shortwaves will
dive through this northwesterly flow and reinforce the trough and
bring chances for snow showers to the region. Confidence is fairly
high that temperatures will run mostly below normal, but there is
much more uncertainty in the timing of any disturbances and
associated snow chances, as well as the magnitude of the temp
departures.
A fairly vigorous Clipper will dive SE into the upper Ohio Valley
late on Saturday, with snow chances in our north and east.
Tremendous bust potential with Sat afternoon max temps, as the GFS
MOS seems to reflect stronger warm advection into west-central KY
resulting in temps nearly 10 degrees warmer than any other guidance.
Have stayed with raw model consensus, which ranges from lower 30s
over the Bluegrass to upper 30s near BWG. Light accumulations
possible Sat night, especially toward the Bluegrass region.
Dry weather and moderating temps Sunday into Monday as heights rise
and a flatter pattern aloft directs the Clippers more across the
Great Lakes. The pattern becomes more amplified toward the middle of
the week, as the cold air is reinforced again. Not confident enough
to include POPs this far out. Temps will trend colder than the
previous forecast, but not as cold as the latest extended GFS MOS,
which is about 10 degrees colder than previous runs for Wed-Thu.
ECMWF is progressive enough that the core of the cold air never
quite settles into the Ohio Valley. Lows in the teens and highs in
the 20s seem to be a safe bet, but it remains to be seen whether we
will be on the higher end or the lower end of that range.
&&
.AVIATION (12Z TAF Update)...
Updated at 600 AM EST Thu Jan 16 2014
An area of low pressure will move into the Ohio Valley today. Out
ahead of this system, southwest winds will increase to 15 to 20
knots, with gusts to around 25 knots. Precipitation will move
mainly into KSDF late this morning, initially falling as light
snow. This snow may just be heavy enough to reduce cigs/vsbys to
MVFR thresholds for a few hours. However, precipitation will begin
to mix with rain and decrease in intensity by the mid to late
afternoon, bringing conditions back up into VFR thresholds. At KLEX
and KBWG, a stray shower or two is possible, but do not expect many
impacts to operations from today`s system, other than the increasing
winds.
A cold front will push through all sites tonight. Scattered snow
showers will develop, which may be moderate to locally heavy at
times overnight into Friday morning. Will continue to handle with
VCSH wording for now, but cigs/vsbys within these showers may
briefly be reduced to MVFR or even IFR thresholds while dropping
quick, light accumulations.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Update.........KJD
Short Term.....KJD
Long Term......RAS
Aviation.......KJD
AREA FORECAST DISCUSSION
NWS CARIBOU ME
652 AM EST THU JAN 16 2014
.SYNOPSIS...
ANOTHER WEAK AREA OF LOW PRESSURE WILL PASS TO OUR EAST ON
THURSDAY. AN UPPER LEVEL TROUGH OF LOW PRESSURE WILL GRADUALLY
MOVE IN FROM THE WEST FRIDAY INTO THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
UPDATE: EXTENDED THE FOG THROUGH THE AFTERNOON FOR THE DOWNEAST
AND COAST BUT BROUGHT VSBYS UP ABOVE 1 MILE BY THAT TIME. DECIDED
TO LEAVE THE DENSE FOG ADVISORY AS IS THROUGH 9 AM. WILL ALLOW
FOG TO FALL OUT OF THE FCST BY 10 AM ACROSS THE NORTH AND WESTERN
AREAS. ADJUSTED THE TEMPERATURES UPWARD AS READINGS HAVE STAYED
IN TH UPPER 20S AND 30S ACROSS THE NORTH AND WEST AND HELD IN THE
LOW TO MID 30S DOWNEAST TO THE COAST. TEMPERATURES ARE FCST TO
RISE SOME TODAY BUT LEVEL OFF AS CLOUDS AND SOME LIGHT PRECIP
MOVES IN LATER ON. CONTINUED ABOVE NORMAL FOR MID JANUARY.
AN UPPER LEVEL DISTURBANCE IS PASSING ACROSS WESTERN MAINE THIS
MORNING TRIGGERING SOME LIGHT SNOW. THE HRRR AND NAM WERE DOING
WELL W/THE CLOUDS AND FOG AS WELL AS THE UPPER LEVEL FEATURE. THE
CLOUDS HAVE KEPT TEMPERATURES UP THIS MORNING AND ADJUSTMENTS WERE
MADE TO ACCOUNT FOR THIS. CLOUDS AND FOG ARE EXPECTED TO LIFT
LATER THIS MORNING BUT SKIES SHOULD REMAIN MOSTLY CLOUDY. THE LOW
CLOUDS AND FOG WILL HANG ON A WHILE LONGER THIS MORNING W/A LIGHT
SSE WIND.
ATTENTION TURNS TO ANOTHER S/WV EXPECTED TO MOVE UP ACROSS THE
REGION LATER TODAY INTO TONIGHT WHILE LOW PRES AT THE SFC PASSES
SE OF THE REGION. THE NAM HAS THIS FEATURE HANDLED WELL AS OF 06Z
AS IT WAS SETTING OFF SNOW OVER NORTHERN NYS AND SOUTHERN QUEBEC.
THIS FEATURE WILL SET OFF SOME LIGHT SNOW OR SNOW SHOWERS ACROSS
THE NORTH AND WEST THIS AFTERNOON INTO THE EVENING. DECIDED TO
BRING PRECIP CHANCES UP TO 40% W/SOME LIGHT SNOWFALL ACCUMULATIONS
OF POSSIBLY AN INCH OR LESS. THE BEST ACCUMULATIONS WILL COME
TONIGHT AS AIR AND SFC TEMPERATURES COOL DOWN. QPF AMOUNTS ATTM
ARE FCST TO BE NO HIGHER THAN 0.10" W/A SNOW RATIO OF 10-12:1.
TEMPERATURES WERE RAISED FOR THE MAXES TODAY W/LOW TO MID 30S
ACROSS THE NORTH AND WEST W/UPPER 30S TO AROUND 40 CENTRAL AND
DOWNEAST. THE MINS TONIGHT WILL REMAIN WELL ABOVE NORMAL GIVEN
HOW THE MOS GUIDANCE HAS BEEN RUNNING LOW THE LAST SEVERAL DAYS.
UNTIL THE UPPER TROF PASSES TO THE EAST, SEE NO REASON FOR A
DRAMATIC COOLDOWN UNTIL AFTER FRIDAY. THIS WILL BE DISCUSSED IN
THE LONG TERM SECTION.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY/...
A BROAD UPPER TROF WILL REMAIN ACROSS THE REGION FRIDAY THROUGH
SATURDAY. A WEAK AREA OF LOW PRESSURE WILL PASS TO THE SOUTH OF NOVA
SCOTIA ON FRIDAY WHILE ANOTHER AREA OF LOW PRESSURE MOVES SLOWLY
EAST FROM THE GREAT LAKES. FRIDAY WILL BE A MAINLY CLOUDY DAY ACROSS
THE REGION WITH A CHANCE OF LIGHT SNOW ACROSS NORTHERN AREAS AND
SNOW OR RAIN ACROSS CENTRAL AND DOWNEAST.
WEAK LOW PRESSURE WILL REMAIN TO OUR NORTHWEST ACROSS QUEBEC FRIDAY
NIGHT THROUGH SATURDAY WITH ANOTHER WEAK AREA OF LOW PRESSURE
EXPECTED TO DEVELOP ACROSS THE SOUTHERN NEW ENGLAND COAST SATURDAY
AND THEN MOVE NORTHEAST TOWARD NOVA SCOTIA. THIS WILL KEEP MOSTLY
CLOUDY SKIES ACROSS THE REGION WITH A FEW SNOW SHOWERS OR FLURRIES
FROM TIME TO TIME.
TEMPERATURES THROUGH THE PERIOD WILL CONTINUE WELL ABOVE NORMAL FOR
THIS TIME OF YEAR.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AN UPPER LEVEL TROF IS EXPECTED TO REMAIN ACROSS THE REGION MOST OF
THE PERIOD. THIS WILL KEEP UNSETTLED CONDITIONS ACROSS THE REGION
WITH THE CHANCE FOR SNOW SHOWERS FROM TIME TO TIME. IT WILL BE
TURNING PROGRESSIVELY COLDER THROUGH THE PERIOD WITH TEMPERATURES BY
EARLY NEXT WEEK RETURNING TO NEAR OR EVEN BELOW NORMAL LEVELS.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
NEAR TERM: IFR/LIFR ESPECIALLY FOR KBGR AND KBHB THIS MORNING WITH
DENSE FOG. IFR/MVFR FOR THE NORTHERN TERMINALS W/A BRIEF IMPROVEMENT
TO MVFR AND POSSIBLY VFR. CONDITIONS WILL THEN DROP BACK TO IFR
W/THE POTENTIAL FOR SNOW ESPECIALLY ACROSS THE NORTHERN TERMINALS.
SHORT TERM: MVFR/IFR CONDITIONS ARE EXPECTED FRIDAY IN LIGHT SNOW
NORTH AND SNOW/RAIN ACROSS THE DOWNEAST TERMINALS. CONDITIONS
SHOULD BE MAINLY VFR FRIDAY NIGHT THROUGH MONDAY.
&&
.MARINE...
NEAR TERM: SCA FOR HAZARDOUS SEAS EXTENDED THROUGH 10 AM. SEAS ARE
STILL RUNNING AT 6-7 FT BUT SHOWING SIGNS OF DROPPING BACK.
CONDITIONS ARE EXPECTED TO BE BELOW SCA CONDITIONS BY THIS
AFTERNOON INTO THE EVENING AS WINDS REMAIN BELOW 10 KT AND WAVE
HEIGHTS DROP TO 3-4 FT.
SHORT TERM: A SMALL CRAFT ADVISORY COULD ME NEEDED FOR SEAS FRIDAY
AND FRIDAY NIGHT. WIND/SEAS SHOULD REMAIN BELOW SMALL CRAFT
ADVISORY LEVELS SATURDAY AND SATURDAY NIGHT. WINDS/SEAS MAY
INCREASE TO SMALL CRAFT ADVISORY LEVELS SUNDAY.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...DENSE FOG ADVISORY UNTIL 9 AM EST THIS MORNING FOR MEZ015>017-
029-030.
MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 10 AM EST THIS
MORNING FOR ANZ050-051.
&&
$$
NEAR TERM...HEWITT
SHORT TERM...DUDA
LONG TERM...DUDA
AVIATION...HEWITT/DUDA
MARINE...HEWITT/DUDA
AREA FORECAST DISCUSSION
NWS CARIBOU ME
441 AM EST THU JAN 16 2014
.SYNOPSIS...
ANOTHER WEAK AREA OF LOW PRESSURE WILL PASS TO OUR EAST ON
THURSDAY. AN UPPER LEVEL TROUGH OF LOW PRESSURE WILL GRADUALLY
MOVE IN FROM THE WEST FRIDAY INTO THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
DECIDED ON A DENSE FOG ADVISORY FOR THE DOWNEAST AND COAST THIS
MORNING AFTER COORDINATING W/GYX. THANKS FOR THE HEADS UP MIKE.
LOW CLOUDS AND FOG ARE THE BIG DEAL THIS MORNING W/AREAS OF DENSE
FOG AT TIMES ACROSS THE DOWNEAST AND COAST. AN UPPER LEVEL DISTURBANCE
IS PASSING ACROSS WESTERN MAINE THIS MORNING TRIGGERING SOME LIGHT
SNOW. THE HRRR AND NAM WERE DOING WELL W/THE CLOUDS AND FOG AS
WELL AS THE UPPER LEVEL FEATURE. THE CLOUDS HAVE KEPT TEMPERATURES
UP THIS MORNING AND ADJUSTMENTS WERE MADE TO ACCOUNT FOR THIS.
THERE IS SOME CONCERN FOR BLACK ICE THIS MORNING AND REFREEZING OF
WATER ON AREA ROADS. A SPECIAL WEATHER STATEMENT WILL BE ISSUED
THIS MORNING TO ADDRESS THIS ISSUE. CLOUDS AND FOG ARE EXPECTED
TO LIFT LATER THIS MORNING BUT SKIES SHOULD REMAIN MOSTLY CLOUDY.
THE LOW CLOUDS AND FOG WILL HANG ON A WHILE LONGER THIS MORNING
W/A LIGHT SSE WIND.
ATTENTION TURNS TO ANOTHER S/WV EXPECTED TO MOVE UP ACROSS THE
REGION LATER TODAY INTO TONIGHT WHILE LOW PRES AT THE SFC PASSES
SE OF THE REGION. THE NAM HAS THIS FEATURE HANDLED WELL AS OF 06Z
AS IT WAS SETTING OFF SNOW OVER NORTHERN NYS AND SOUTHERN QUEBEC.
THIS FEATURE WILL SET OFF SOME LIGHT SNOW OR SNOW SHOWERS ACROSS
THE NORTH AND WEST THIS AFTERNOON INTO THE EVENING. DECIDED TO
BRING PRECIP CHANCES UP TO 40% W/SOME LIGHT SNOWFALL ACCUMULATIONS
OF POSSIBLY AN INCH OR LESS. THE BEST ACCUMULATIONS WILL COME
TONIGHT AS AIR AND SFC TEMPERATURES COOL DOWN. QPF AMOUNTS ATTM
ARE FCST TO BE NO HIGHER THAN 0.10" W/A SNOW RATIO OF 10-12:1.
TEMPERATURES WERE RAISED FOR THE MAXES TODAY W/LOW TO MID 30S
ACROSS THE NORTH AND WEST W/UPPER 30S TO AROUND 40 CENTRAL AND
DOWNEAST. THE MINS TONIGHT WILL REMAIN WELL ABOVE NORMAL GIVEN
HOW THE MOS GUIDANCE HAS BEEN RUNNING LOW THE LAST SEVERAL DAYS.
UNTIL THE UPPER TROF PASSES TO THE EAST, SEE NO REASON FOR A
DRAMATIC COOLDOWN UNTIL AFTER FRIDAY. THIS WILL BE DISCUSSED IN
THE LONG TERM SECTION.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY/...
A BROAD UPPER TROF WILL REMAIN ACROSS THE REGION FRIDAY THROUGH
SATURDAY. A WEAK AREA OF LOW PRESSURE WILL PASS TO THE SOUTH OF NOVA
SCOTIA ON FRIDAY WHILE ANOTHER AREA OF LOW PRESSURE MOVES SLOWLY
EAST FROM THE GREAT LAKES. FRIDAY WILL BE A MAINLY CLOUDY DAY ACROSS
THE REGION WITH A CHANCE OF LIGHT SNOW ACROSS NORTHERN AREAS AND
SNOW OR RAIN ACROSS CENTRAL AND DOWNEAST.
WEAK LOW PRESSURE WILL REMAIN TO OUR NORTHWEST ACROSS QUEBEC FRIDAY
NIGHT THROUGH SATURDAY WITH ANOTHER WEAK AREA OF LOW PRESSURE
EXPECTED TO DEVELOP ACROSS THE SOUTHERN NEW ENGLAND COAST SATURDAY
AND THEN MOVE NORTHEAST TOWARD NOVA SCOTIA. THIS WILL KEEP MOSTLY
CLOUDY SKIES ACROSS THE REGION WITH A FEW SNOW SHOWERS OR FLURRIES
FROM TIME TO TIME.
TEMPERATURES THROUGH THE PERIOD WILL CONTINUE WELL ABOVE NORMAL FOR
THIS TIME OF YEAR.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AN UPPER LEVEL TROF IS EXPECTED TO REMAIN ACROSS THE REGION MOST OF
THE PERIOD. THIS WILL KEEP UNSETTLED CONDITIONS ACROSS THE REGION
WITH THE CHANCE FOR SNOW SHOWERS FROM TIME TO TIME. IT WILL BE
TURNING PROGRESSIVELY COLDER THROUGH THE PERIOD WITH TEMPERATURES BY
EARLY NEXT WEEK RETURNING TO NEAR OR EVEN BELOW NORMAL LEVELS.
&&
.AVIATION /09Z THURSDAY THROUGH MONDAY/...
NEAR TERM: IFR/LIFR ESPECIALLY FOR KBGR AND KBHB THIS MORNING WITH
DENSE FOG. IFR/MVFR FOR THE NORTHERN TERMINALS W/A BRIEF IMPROVEMENT
TO MVFR AND POSSIBLY VFR. CONDITIONS WILL THEN DROP BACK TO IFR
W/THE POTENTIAL FOR SNOW ESPECIALLY ACROSS THE NORTHERN TERMINALS.
SHORT TERM: MVFR/IFR CONDITIONS ARE EXPECTED FRIDAY IN LIGHT SNOW
NORTH AND SNOW/RAIN ACROSS THE DOWNEAST TERMINALS. CONDITIONS
SHOULD BE MAINLY VFR FRIDAY NIGHT THROUGH MONDAY.
&&
.MARINE...
NEAR TERM: SCA FOR HAZARDOUS SEAS EXTENDED THROUGH 10 AM. SEAS ARE
STILL RUNNING AT 6-7 FT BUT SHOWING SIGNS OF DROPPING BACK.
CONDITIONS ARE EXPECTED TO BE BELOW SCA CONDITIONS BY THIS
AFTERNOON INTO THE EVENING AS WINDS REMAIN BELOW 10 KT AND WAVE
HEIGHTS DROP TO 3-4 FT.
SHORT TERM: A SMALL CRAFT ADVISORY COULD ME NEEDED FOR SEAS FRIDAY
AND FRIDAY NIGHT. WIND/SEAS SHOULD REMAIN BELOW SMALL CRAFT
ADVISORY LEVELS SATURDAY AND SATURDAY NIGHT. WINDS/SEAS MAY
INCREASE TO SMALL CRAFT ADVISORY LEVELS SUNDAY.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...DENSE FOG ADVISORY UNTIL 9 AM EST THIS MORNING FOR MEZ015>017-
029-030.
MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 10 AM EST THIS
MORNING FOR ANZ050-051.
&&
$$
NEAR TERM...HEWITT
SHORT TERM...DUDA
LONG TERM...DUDA
AVIATION...HEWITT/DUDA
MARINE...HEWITT/DUDA
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
951 PM EST FRI JAN 17 2014
.SYNOPSIS...
A COLD FRONT WILL CROSS THE REGION TONIGHT INTO EARLY SATURDAY
MORNING. HIGH PRESSURE WILL RETURN BY SATURDAY AFTERNOON. ANOTHER
COLD FRONT WILL SWING ACROSS THE REGION ON SUNDAY. AN EXTENDED
PERIOD OF WELL BELOW NORMAL TEMPERATURES IS EXPECTED DURING THE
MIDDLE AND END OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
NO MAJOR CHANGES NEC TO THE FORECAST PACKAGE TNGT. WITH 00Z NAM
AND RAP COMING IN DRY ACROSS THE AREA SEE NO REASON TO BUMP UP
POPS HIGHER THAN 20% OVRNGT. CAN`T RULE OUT SOME
SPRINKLES/FLURRIES OVR NRN AREAS. OTHERWISE...PRTLY CLOUDY ON AVG
WITH LO TEMPS RANGING FRM THE MID/UPR 20S OVR THE PIEDMONT TO THE
MID/UPR 30S NEAR THE CST.
PREVIOUS DISCUSSION...
A COLD FRONT WILL QUICKLY APPROACH THE LOCAL AREA BY THIS
EVENING...THEN MOVES THRU TONIGHT INTO EARLY SAT MORNING. LATEST
MODEL GUIDANCE IS NOT ALL THAT ENTHUSIASTIC ABOUT THE CHANCE FOR
MEASURABLE PCPN ACROSS THE FA TONIGHT. THIS IS MOSTLY DUE TO THE
FAR NE TRACK OF THE UPPER LOW (ACROSS THE OH VALLEY/EASTERN GREAT
LAKES) AND THE FAR NORTHERN TRACK OF THE SFC LOW. THE MODELS DUE
SHOW A LITTLE ENERGY TRANSLATING TO THE COAST AND INTERACTING WITH
THE GULF STREAM BETWEEN 06Z-12Z. HOWEVER...BY THEN IT WILL BE TOO
LITTLE TOO LATE FOR OUR FA SINCE THE COLD FRONT WILL BE THRU BY
THEN AND THE BEST CHANCE FOR PCPN REMAINS OFFSHORE. WILL CARRY
MAINLY GHOST POPS OVERNIGHT (<15%) FOR THE POSSIBILITY OF ISOLATED
SPRINKLES/FLURRIES AS THE FRONT PASSES. SLIGHT CHC POPS (20%) WERE
LEFT IN THE FAR NW COUNTIES BETWEEN 03-06Z...THEN ACROSS FAR
EASTERN AREAS BETWEEN 06-12Z. AT BEST...THERE MAY BE A QUICK SNOW
SHOWER IN THESE AREAS WITH NO SNOW ACCUMULATION EXPECTED. LOWS
TONIGHT IN THE MID 20S NW TO THE MID 30S AT THE COAST.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH MONDAY/...
A BRIEF RETURN OF HIGH PRESSURE WILL OCCUR ON SATURDAY WITH
PLENTY OF SUNSHINE. TEMPS WILL BE COOLER THAN TODAY IN THE WAKE
OF THE COLD FRONT. HIGHS IN THE MID 30S TO LOW 40S WITH A DECENT
BREEZE...MAKING IT FEEL LIKE THE 20S.
NEXT POTENT SHORTWAVE (AND ASSOCIATED COLD FRONT) DIGS ACROSS THE
OH VALLEY EARLY SAT NGT...THEN SWINGS THRU THE MID ATLANTIC LATE
SAT NIGHT INTO MIDDAY SUN. THIS SYSTEM WILL ALSO HAVE LIMITED LOW
LEVEL MOISTURE TO WORK WITH...AND COMBINED WITH THE SHEERING
NATURE OF THE UPR TROUGH WILL MAKE IT HARD TO PRODUCE ANY
ACCUMULATING PCPN. WILL KEEP THE FORECAST DRY SAT NIGHT...THEN
MAINTAIN SLIGHT CHC POPS (20%) ACROSS THE EASTERN SHORE SUN
MORNING. CANNOT RULE OUT A FEW FLURRIES SUN MORNING ACROSS THE
ENTIRE CWA. BECOMING PARTLY OR MOSTLY SUNNY FROM LATE SUN MORNING
THRU SUN AFTN...AS THAT FRONT PUSHES OUT TO SEA AND HIGH PRESSURE
BUILDS IN FROM THE SW. BREEZY WITH MAX TEMPS IN THE 40S TO NR 50.
HIGH PRESSURE REMAINS IN PLACE MONDAY MORNING BEFORE A COLD FRONT
SAGS SOUTHWARD INTO THE AREA LATE MONDAY AFTERNOON. DRY WITH
HIGHS IN THE 50S TO AROUND 60.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
MODELS AGREE ON GENERAL PATTERN IN THE MEDIUM RANGE WHICH WILL BE
DOMINATED BY STRONG RIDGING ACRS WESTERN NORTH AMERICA...AND A DEEP
TROUGH OVER EASTERN CANADA AND THE GREAT LAKES. DIFFERENCES ARE
FAIRLY MINIMAL SO CONFIDENCE IS HIGH THAT WELL BELOW AVG
TEMPERATURES WILL PREVAIL DURING THE PERIOD...ESPECIALLY WED/THU.
OVERALL...CONDITIONS LOOK DRY AS ARCTIC AIRMASS OVERSPREADS THE
REGION FROM LATE TUE AND BEYOND. STILL SOME QUESTION THOUGH AS TO
POTENTIAL FOR SOME SNOW TUE/TUE NIGHT AS A POTENT UPPER LEVEL
SHORTWAVE TRACKS THROUGH THE MID ATLC/SE STATES AND DEVELOPS A SFC
LOW OFF THE NC COAST. CURRENT PATTERN DEPICTED BY LATEST
GFS/ECMWF/GLOBAL IS TOO PROGRESSIVE FOR MORE THAN A LOW CHC FOR
PRECIP SO WILL ONLY CARRY 20% POPS MOST AREAS AND 30% CHC FOR SE
VA/NE NC AT THIS TIME. HIGHS TUE AVG IN THE LOW 40S NE NC TO THE
LOW-MID 30S ACRS THE FAR NORTH...WITH LOWS WED IN THE TEENS NW TO
THE MID/UPPER 20S SE. EXPECT PARTLY CLOUDY TO VARIABLY SKIES
WED-FRI...ANOTHER WEAK SYSTEM MAY AFFECT THE REGION SOMETIME THU
ALTHOUGH MODELS DIVERGE IN TIMING THE SHORTWAVES IN THE W/NW FLOW
PATTERN BY THIS TIME. HIGHS WED LIKELY STAY IN THE UPPER 20S FROM
RICHMOND ON NORTH...WITH ONLY LOW 30S ACRS THE SOUTH. ONLY A SLIGHT
MODERATION EXPECTED THU/FRI...WITH HIGHS MAINLY IN THE 30S AND LOWS
IN THE TEENS TO LWR 20S.
&&
.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
VFR PREVAILS AT ALL TERMINALS...AND SHOULD PERSIST THROUGH 00Z
SUNDAY. COLD FRONT MOVES THROUGH THE REGION OVERNIGHT...WITH
CEILINGS LOWERING TO 5-6 KFT FOR A FEW HOURS AROUND FRONTAL
PASSAGE. WINDS SHOULD BE GUSTY BEHIND THE FRONT ON SATURDAY...WITH
GUSTS AROUND 20 KTS ALL TERMNALS BUT KSBY...WHERE GUSTS AROUND 25
KTS POSSIBLE.
OUTLOOK...MAINLY VFR AND DRY WEATHER IS FORECAST THROUGH TUESDAY.
ANOTHER COLD FRONT MOVES THROUGH SUNDAY WITH GUSTY WEST WINDS.
COULD BE A FEW SNOW SHOWERS WITH THIS FRONT...BUT MOST TERMINALS
WILL SEE THIS FRONT COME THROUGH DRY. ANY SNOW SHOWERS WILL BE
LIGHT...WITH NO WORSE THAN MVFR CONDITIONS. COLD CYCLONIC FLOW
WILL PERSIST MUCH OF THE NEXT WEEK...WITH SNOW SHOWERS POSSIBLE
AROUND MID WEEK.
&&
.MARINE...
SCA CONDS ARE IN EFFECT FOR W/NW WINDS FOLLOWING A COLD FRONT EARLY
SATURDAY MORNING. FOLLOWED CLOSE TO THE NAM FOR WINDS. CONDS WILL BE
MARGINAL BUT STRONG ENOUGH TO ADD HEADLINES TO ALL THE WATERS EXCEPT
THE COASTAL WATERS SOUTH OF CAPE CHARLES. CURRENT SCA ENDS AT 00Z
SATURDAY EVENING. CONDS MAY REDEVELOP SUNDAY AND SUNDAY NIGHT.
FUTURE SHIFTS MAY CONSIDER THE OPTION OF EXTENDING THE HEADLINES
THROUGH SATURDAY NIGHT BECAUSE THE LULL IN CONDITIONS COULD BE LESS
THAN 12 HOURS.
BENIGN CONDITIONS ARE INDICATED FOR MONDAY AND TUESDAY. MORE
HEADLINES MAY BE NEEDED LATER IN THE WEEK AS MORE COLD AIR POURS
INTO THE REGION.
&&
.EQUIPMENT...
THE NOAA ALL HAZARD WEATHER RADIO (KHB-57) EMANATING FROM DRIVER,
VA ON A FREQUENCY OF 162.550 MHZ WILL BE OFF THE AIR UNTIL
FURTHER NOTICE DUE TO ANTENNA PROBLEMS. RETURN TO NORMAL SERVICE
IS NOT KNOWN AT THIS TIME.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 4 AM TO 7 PM EST SATURDAY FOR
ANZ635>638.
SMALL CRAFT ADVISORY FROM 1 AM TO 7 PM EST SATURDAY FOR
ANZ630>632-634.
SMALL CRAFT ADVISORY FROM 7 AM TO 7 PM EST SATURDAY FOR ANZ633-
650-652-654.
&&
$$
SYNOPSIS...JDM
NEAR TERM...JDM/MAS
SHORT TERM...JDM
LONG TERM...LKB
AVIATION...WRS
MARINE...LSA/WRS
EQUIPMENT...
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
335 PM CST THU JAN 16 2014
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 330 PM CST THU JAN 16 2014
995 MB SFC LOW CENTERED ALONG THE WI/MI BORDER HAS BEEN SLOWLY
FILLING TODAY. HOWEVER...THIS LOW HAS A STRONG ARCTIC COLD FRONT NOW
ROLLING SOUTH ACROSS IA. 6-10 MB 3 HOUR PRESSURE RISES MOVING SOUTH
ACROSS THE DAKOTAS IN THE ARCTIC FRONTS WAKE HAS HELPED WINDS GUST
TO AROUND 50 MPH FOR WHERE THE BLIZZARD WARNING IS CURRENTLY IN
PLACE. THESE HAVE NOT BEEN THE STRONGEST WINDS HOWEVER...AS WIND
GUSTS HAVE BEEN PUSHING 60 MPH FROM SE SODAK INTO WRN IA...IN
ACCORDANCE WITH WHERE THE CORE OF THE STRONGEST H85 WINDS ARE GOING.
IN ADDITION TO THE STRONG WINDS...WATER VAPOR IMAGERY SHOWS A COUPLE
OF SHORT WAVES ROTATING AROUND AN UPPER LOW CENTERED NEAR WRN LAKE
SUPERIOR. THESE UPPER WAVES HAVE RESULTED IN SOME LIGHT SNOW JOINING
IN WITH THE BLOWING SNOW...WHICH HAS HELPED WITH VISIBILITY
REDUCTIONS.
AS FOR THE HEADLINES...TEMPERATURES THAT GOT UP TO BETWEEN 32 AND 35
ACROSS MOST OF THE AREA LAST NIGHT INTO THE MORNING MOISTENED UP THE
SNOW PACK ENOUGH TO MAKE THE SNOW A LITTLE LESS BLOWABLE. THIS HAS
LIMITED THE AMOUNT OF QUARTER MILE OR LESS VISIBILITIES WE HAVE SEEN
ACROSS THE AREA...AT LEAST AT THE 10 FOOT LEVEL WHERE AIRPORT
VISIBILITY EQUIPMENT RESIDES. HOWEVER...SEEING PICTURES ON SOCIAL
MEDIA FROM ACROSS THE AREA AND MNDOT WEBCAMS...WE ARE SEEING THAT
DOWN CLOSER TO GROUND LEVEL...THE VISIBILITIES ARE QUITE A BIT WORSE
AT TIMES...WITH NEAR WHITEOUT CONDITIONS BEING OBSERVED. EVEN IF THE
WHITEOUT CONDITIONS ARE NOT BEING OBSERVED...THE SNOW BLOWING ACROSS
THE ROADWAYS IS RESULTING IN VERY ICY CONDITIONS ON THE ROADS...AND
WHEN COMBINING ICY ROADS WITH WIND GUSTS IN EXCESS OF 40 MPH PUSHING
VEHICLES AROUND...TRAVEL REMAINS QUITE TREACHEROUS ACROSS THE
REGION. AS A RESULT...MADE NO CHANGES TO CURRENT HEADLINES.
LOOKING AT WINDS...THEY LIKELY REACHED THEIR PEAK BETWEEN NOON AND 3
PM. WITH THE ISALLOBARIC HIGH NOW PUSHING INTO THE SIOUX FALLS
AREA...WE WILL START TO SLOWLY SEE THEM SUBSIDE THE REST OF THE
AFTERNOON AND EVENING. WITH BLIZZARD CONDITIONS EXPECTED TO SLOWLY
SUBSIDE AS WELL.
OF COURSE THESE WINDS HAVE ALSO BROUGHT IN SOME MUCH COLDER AIR...AS
EVIDENCED BY THE FACT THAT SINCE GETTING TO THE OFFICE HERE IN
CHANHASSEN AT 7 THIS MORNING...THE TEMPERATURE HAS FALLEN FROM ITS
DOWNRIGHT BALMY 34 DOWN TO JUST 9 ABOVE AT 3 PM. THESE COLD
TEMPERATURES ALONG WITH THE STRONGER WINDS WILL LEAD TO ANOTHER
ISSUE FOR TONIGHT AND THIS IS WITH WIND CHILLS. AT THE
MOMENT...APPARENT TEMPERATURES IN THE BLIZZARD WARNING ARE FORECAST
TO DIP TO BETWEEN -25 AND -30 TONIGHT INTO FRI MORNING...MEANING A
WIND CHILL ADVISORY WILL LIKELY NEED TO BE ISSUED LATER THIS
EVENING. WE ALREADY HAVE THE WIND CHILLS MENTIONED IN THE BLIZZARD
WARNING...SO SUSPECT THAT ONCE IT IS DECIDED TO DROP THE BLIZZARD
WARNING IT WILL NEED TO BE REPLACED BY A WIND CHILL ADVISORY.
AFTER TONIGHT...REST OF THE SHORT TERM IS PRETTY QUITE AS A SFC
RIDGE AXIS MOVES IN FOR FRIDAY...GIVING US A RATHER COOL DAY WITH
HIGHS ONCE AGAIN 10 TO 15 DEGREES BELOW NORMAL AS SKIES CLEAR OUT
FROM WEST TO EAST IN THE MORNING. FOR LOWS TONIGHT...RECENT HISTORY
OF MODEL PERFORMANCE WOULD SAY TO AVOID THE LOWER END OF
GUIDANCE...SO HAVE FAVORED LOWS TONIGHT TOWARD THE BIAS CORRECTED
ECMWF AND RAW MODEL DATA...WHICH STILL GIVES YOU LOWS AROUND -10 IN
THE WEST...ZERO IN THE TWIN CITIES AND AROUND 5 ABOVE IN THE FAR
EASTERN MPX AREA.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 330 PM CST THU JAN 16 2014
ALMOST A BROKEN RECORD FOR THIS WINTER SEASON AS THE NORTHWEST
FLOW CONTINUES ACROSS THE UPPER MIDWEST THROUGH THE NEXT 7 TO 10
DAYS. THIS WILL KEEP TEMPS BLW NORMAL WITH SEVERAL SHRTWV/S
EMBEDDED IN THIS NW FLOW KEEPING CHC/S OF SNOW THRU THE PERIOD.
HOWEVER...DUE TO THIS NW FLOW...MOST OF THE STORM SYSTEM WILL BE
FAIRLY WEAK AND FAST IN TERMS OF DEVELOPING AND ENDING THE
PRECIPITATION IN A 12 TO 24 HR PERIOD. THE FIRST OF THESE SHRTWV/S
WILL ARRIVE FRIDAY NIGHT...AND QUICKLY MOVE SOUTHEAST OF THE AREA
BY SATURDAY AFTN. AS WITH MOST CLIPPER TYPE SYSTEMS...PWATS ARE
LOW KEEPING SNOWFALL RATIOS HIGH OR ROUGHLY 20 TO 25-1.
THEREFORE...EVEN A LOW AMT OF QPF 0.10 TO 0.20"...WILL TRANSLATE
TO 2 TO 4 INCHES OF SNOWFALL. IN ADDITION TO THE SNOWFALL...THE
STRONG NATURE OF HOW THESE SYSTEM WRAP UP QUICKLY OR
INTENSIFY...BLOWING AND DRIFTING SNOW WILL BECOME A PROBLEM. THIS
WILL BE ESPECIALLY NOTED IN WC/SC MN WHERE TODAY/S SYSTEM BROUGHT
BLIZZARD CONDS TO THE AREA. ONE MINOR CHG TO SUNDAY/S FORECAST IS
TO LOWER TEMPS A FEW DEGREES. THIS IS BASED ON A MORE NW FLOW AND
KEEPS THE WARMER PACIFIC AIR MASS FURTHER TO THE WEST ACROSS THE
DAKOTAS. A BIGGER CONCERN DEVELOPS OUTSIDE OF THE FORECAST TIME
FRAME WHICH IS THE WEEKEND OF JAN 25TH. AS WITH THE DEEP UPPER LOW
THAT MOVED ACROSS THE UPPER MIDWEST THE FIRST WEEK OF
JANUARY...THERE IS A SIMILAR SYSTEM PROGGED TO MOVE OVER THE SAME
AREA THE WEEKEND OF JAN 25/26TH. 85H TEMPS ARE SIMILAR IN TERMS OF
HOW COLD IT COULD GET ONCE AGAIN.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1226 PM CST THU JAN 16 2014
WINDS BEGINNING INTENSIFY AGAIN IN THE WAKE OF THE ARCTIC COLD
FRONT THAT IS RAPIDLY APPROACHING IOWA. PRESSURE RISES ON THE
ORDER OF 10 MB IN 3 HRS PUSHING SOUTH THROUGH NODAK HELPING TO
BOOST WIND SPEEDS IN THE WEST. CURRENT TAFS HAD WINDS HANDLED
WELL...SO CHANGED THEM LITTLE. VIS STARTING TO RESPOND TO THIS
SECOND BURST OF WIND AS WELL...SO DID TEMPO IN SOME 1/2SM VSBYS IN
BLSN FOR AXN/RWF. CIGS HAVE BECOME VFR IN THE WAKE OF THE COLD
FRONT...BUT EXPECT MVFR CIGS TO RETURN AS SNOW ASSOCIATED WITH
UPPER WAVE OVER THE ARROWHEAD DROPS SOUTH THIS AFTERNOON AND
EVENING PER THE HRRR AND RAP. GFSLAMP GUIDANCE LOOKS TO HAVE A
GOOD HANDLE ON TRENDS THIS AFTERNOON...SO FOLLOWED THAT AS A
START FOR BRINGING -SN AND MVFR CIGS BACK. EXPECT CLEARING SKIES
TO SLOWLY WORK EAST ACROSS THE AREA TONIGHT...THOUGH THIS CLEARING
LIKELY WILL NOT REACH THE EAU AREA UNTIL AFTER 18Z FRI.
KMSP...HIGH CONFIDENCE IN THE WIND FORECAST...BUT DO BELIEVE
CURRENT TAF IS ON THE HIGHER END OF WHERE WE WILL SEE THINGS THIS
AFTERNOON. LOWER CONFIDENCE ON SNOW MOVING BACK IN...BUT WITH THE
HRRR AND GFSLAMP SHOWING SIMILAR TRENDS...FELT CONFIDENT ENOUGH TO
REINTRODUCE -SN AND MVFR CONDS. HARD TO SAY IF CIGS WILL RETURN TO
MVFR CONDS BASED ON UPSTREAM OBS...AS BLSN IS CONTAMINATING MANY
OF THE LOWER CIGS WE ARE SEEING TO THE NW.
/OUTLOOK FOR KMSP/
FRI NIGHT...MVFR/IFR AND -SN DEVELOPING. WINDS S AT 15KTS.
SAT...MVFR/-SN IN MORNING...THEN VFR. WINDS NW AT 20G30KTS.
SUN...VFR. WINDS W 5-10KTS.
MON...VFR. WINDS NW 10-15KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...BLIZZARD WARNING UNTIL MIDNIGHT CST TONIGHT FOR MNZ041-047>049-
054>058-064>067-073>076-082>085-091>093.
WINTER WEATHER ADVISORY UNTIL 6 AM CST FRIDAY FOR MNZ042>045-
050>053-059>063-068>070-077-078.
WI...NONE.
&&
$$
SHORT TERM...MPG
LONG TERM...JLT
AVIATION...MPG
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1227 PM CST THU JAN 16 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 308 AM CST THU JAN 16 2014
THE LONG AWAITED BLIZZARD CONDITIONS HAVE ARRIVED ACROSS THE RED
RIVER VALLEY...AND THESE WILL SPREAD SOUTHWARD ACROSS THE
MINNESOTA RIVER VALLEY DURING THE MORNING HOURS. THE LACK OF
FALLING SNOW WILL CONFINE THE PURE WHITEOUT CONDITIONS TO OPEN
AREAS. HOWEVER ROADS ARE ALREADY CLOSED IN NORTHWEST MN...SO WOULD
EXPECT THESE DETERIORATING CONDITIONS EXPAND ACROSS ALL OF WESTERN
MN AS THE ARCTIC FRONT PUSHES THROUGH THE REGION. FORECAST
SOUNDINGS CONTINUE TO INDICATE NEAR 50KT GUST POTENTIAL WITH THE
FRONTAL PASSAGE...WITH 40KT GUSTS EXPECTED TO CONTINUE MOST OF THE
DAY. OCCASIONAL SNOW SHOWERS WILL DEVELOP AS A WEAK UPPER LEVEL
VORT MAX ROTATES ACROSS THE REGION THIS MORNING. MEANWHILE
ELEVATED INSTABILITY ATOP THE BOUNDARY LAYER WOULD INDICATE THE
POTENTIAL FOR A FEW SHALLOW CONVECTIVE ROLLS. TEMPERATURES WILL
FALL QUICKLY BEHIND THE FRONT...WITH FRIDAY MORNING LOWS BOTTOMING
OUT NEAR -10F ACROSS THE NORTHWEST...NEAR ZERO ACROSS EASTERN
MN...AND SINGLE DIGITS IN WESTERN WI.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 308 AM CST THU JAN 16 2014
WITH THE POTENT BLIZZARD-MAKING SYSTEM HAVING SHIFTED INTO THE ERN
GRT LKS BY FRI MRNG...A SPOKE OF HIGH PRES EXTENDING NEWD FROM ITS
CENTER OVER SRN SD/NRN IA WILL SLIDE E OVER THE AREA DURG THE DAY
FRI. THIS WILL ONLY BE A SHORT-LIVED BREAK IN THE ACTION AS THE
TROF OVER THE ERN NOAM STRENGTHENS...MAKING MORE OF A MERIDIONAL
UPR LVL FLOW OVER CENTRAL NOAM. THIS FLOW WILL ALLOW A COMPACT LOW
PRES CENTER DRIVE SSE FROM WRN CANADA INTO MN FRI NIGHT. THIS LOW
WILL THEN EJECT OUT INTO WI/IL BY MIDDAY SAT. CONFIDENCE REMAINS
HIGH AMONG THE MODELS IN BOTH TIMING AND IMPACTS AS IT LOOKS TO
CARRY ENOUGH LIFT AND QPF TO PRODUCE 1-2 INCHES OVER CENTRAL-ERN
PORTIONS OF THE CWFA FRI NIGHT INTO SAT MRNG. HAVE REMOVED POPS
FOR DURG THE DAY ON FRI AS ITS PROGRESS HAS SLOWED A BIT...BUT IT
WILL PUSH THRU THE CWFA FRI NIGHT INTO EARLY SAT MRNG. TEMPS WILL
BE COLD ENOUGH SUCH THAT THE SNOW WILL BE A DRY POWDERY SNOW...
THEN COMBINED WITH STRONG WINDS ON THE BACK SIDE...BLOWING AND
DRIFTING SNOW WILL AGAIN BE AN ISSUE. HOWEVER...ATTM...WIND SPEEDS
LOOK TO BE NOT STRONG ENOUGH SUCH THAT BLIZZARD CONDS WOULD
DEVELOP. ONCE THIS SYSTEM EXITS BY MIDDAY SAT...THEN NO ORGANIZED
STORM SYSTEMS LOOK TO IMPACT THE AREA THROUGH THE MIDDLE OF NEXT
WEEK. THAT BEING SAID...TEMPERATURES WILL BE ON QUITE THE ROLLER
COASTER OVER THE NEXT 5-7 DAYS. SEVERAL WEAK WAVES IN THE H5
PATTERN WILL ALLOW FOR A FEW RIDGE-LIKE WAVES THAT WILL RESULT IN
SOME WARMING OVER THE WEEKEND...THEN REINFORCEMENT OF THE ERN TROF
WITH A WRN RIDGE WILL MAKE FOR ANOTHER STRONG SURGE OF ARCTIC AIR
TO DROP INTO THE REGION STARTING TUE. HIGHS WILL RISE INTO THE 30S
BY SUN...THEN DROP BACK TO THE SINGLE DIGITS TUE-WED.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1226 PM CST THU JAN 16 2014
WINDS BEGINNING INTENSIFY AGAIN IN THE WAKE OF THE ARCTIC COLD
FRONT THAT IS RAPIDLY APPROACHING IOWA. PRESSURE RISES ON THE
ORDER OF 10 MB IN 3 HRS PUSHING SOUTH THROUGH NODAK HELPING TO
BOOST WIND SPEEDS IN THE WEST. CURRENT TAFS HAD WINDS HANDLED
WELL...SO CHANGED THEM LITTLE. VIS STARTING TO RESPOND TO THIS
SECOND BURST OF WIND AS WELL...SO DID TEMPO IN SOME 1/2SM VSBYS IN
BLSN FOR AXN/RWF. CIGS HAVE BECOME VFR IN THE WAKE OF THE COLD
FRONT...BUT EXPECT MVFR CIGS TO RETURN AS SNOW ASSOCIATED WITH
UPPER WAVE OVER THE ARROWHEAD DROPS SOUTH THIS AFTERNOON AND
EVENING PER THE HRRR AND RAP. GFSLAMP GUIDANCE LOOKS TO HAVE A
GOOD HANDLE ON TRENDS THIS AFTERNOON...SO FOLLOWED THAT AS A
START FOR BRINGING -SN AND MVFR CIGS BACK. EXPECT CLEARING SKIES
TO SLOWLY WORK EAST ACROSS THE AREA TONIGHT...THOUGH THIS CLEARING
LIKELY WILL NOT REACH THE EAU AREA UNTIL AFTER 18Z FRI.
KMSP...HIGH CONFIDENCE IN THE WIND FORECAST...BUT DO BELIEVE
CURRENT TAF IS ON THE HIGHER END OF WHERE WE WILL SEE THINGS THIS
AFTERNOON. LOWER CONFIDENCE ON SNOW MOVING BACK IN...BUT WITH THE
HRRR AND GFSLAMP SHOWING SIMILAR TRENDS...FELT CONFIDENT ENOUGH TO
REINTRODUCE -SN AND MVFR CONDS. HARD TO SAY IF CIGS WILL RETURN TO
MVFR CONDS BASED ON UPSTREAM OBS...AS BLSN IS CONTAMINATING MANY
OF THE LOWER CIGS WE ARE SEEING TO THE NW.
/OUTLOOK FOR KMSP/
FRI NIGHT...MVFR/IFR AND -SN DEVELOPING. WINDS S AT 15KTS.
SAT...MVFR/-SN IN MORNING...THEN VFR. WINDS NW AT 20G30KTS.
SUN...VFR. WINDS W 5-10KTS.
MON...VFR. WINDS NW 10-15KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...BLIZZARD WARNING UNTIL MIDNIGHT CST TONIGHT FOR MNZ041-047>049-
054>058-064>067-073>076-082>085-091>093.
WINTER WEATHER ADVISORY UNTIL 6 AM CST FRIDAY FOR MNZ042>045-
050>053-059>063-068>070-077-078.
WI...NONE.
&&
$$
SHORT TERM...JRB
LONG TERM...JPC
AVIATION...MPG
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
315 AM CST Thu Jan 16 2014
.SHORT TERM: (Through Late This Afternoon)
Issued at 306 AM CST Thu Jan 16 2014
Three disturbances imbedded within NW upper flow will impact our
area through late this afternoon today.
The first is producing an area of pcpn that has greatly expanded
early this morning and is now moving into STL metro. Reports from
spotters and media indicate rather solid light accums, ranging from
a dusting to a half inch. While not much, it may still have a
decent impact with slick spots on untreated areas as we head into
the morning rush hour. Expect this area of pcpn to push thru
continuing with light accums, including STL metro. Areas further to
the N and W will also experience some changeover in pcpn types to
rain or sleet as warmer air attempts to push in ahead of yet another
surface reflection of a clipper system.
There is a second area of pcpn moving thru NW MO and into SE IA, but
this thus far has taken the form of a very narrow band of pcpn. 4km
NMM and ARW WRF models want to expand and amplify this as it drops
SE thru the CWA, but other models want to discount. Will keep an
eye on this and make adjustments as needed, but for now am leaning
towards just chance PoPs.
The third area will be in the wake of the cold front associated with
the clipper system. While the main pcpn effects from the clipper
proper will be well to our N and E, scattered rain and snow showers
will be expected later this afternoon with a late surge of lo level
CAA.
It will also get windy behind the cold front this afternoon, with
gusts to 35-40mph, especially in northeast and central MO. A modest
temp drop will also occur this afternoon, but will be largely
restricted to N MO and central IL with the bulk of the strong CAA
holding off until late and tonight.
TES
.LONG TERM: (Tonight through Wednesday)
Issued at 306 AM CST Thu Jan 16 2014
Another shot of cold air will drop sewd into our forecast area tgt
as shortwaves continue to drop sewd through the region and deepen
the upper level trough over the Great Lakes region. The models
lower the 850 mb temperatures down to around -20 degrees C at
least across portions of nern MO and w cntrl IL by 12z Friday.
There will also be some light snow, snow showers or at least
flurries tgt. Flurries may linger Friday mrng across the IL
counties of our forecast area until the upper level trough shifts
east of the region. Temperatures will be below normal for Thursday
ngt and Friday. With increasing low-mid level waa Friday ngt and
the surface wind becoming swly, temperatures will fall Friday evng
but then may become nearly steady late Friday ngt. A Clipper type,
nw flow upper level low and associated weak sfc low will drop sewd
through portions of swrn WI, ern IA and nrn IL on Saturday,
although the models have slight differences on the exact track. It
still appears that the more significant snow will remain ne of our
forecast area Saturday aftn and evng, although there may be light
snow or at least flurries across the IL counties of our forecast
area especially if the track of the low is a little further sw.
This upper level low and associated sfc low will bring a quick
shot of colder air into our area Saturday ngt, but then
temperatures will warm back up quickly for Sunday as upper level
heights begin to rise and the surface wind backs around to a swly
direction. Colder air will gradually sag swd into our area Monday
and Monday ngt with upper level troughing developing over the
Great Lakes region and a relatively strong sfc ridge building sewd
into MO, particularly as depicted by the GFS model. After above
normal high temperatures on Sunday and Monday, highs will return
to below normal for Tuesday.
GKS
&&
.AVIATION: (For the 06z TAFs through 06z Thursday Night)
Issued at 1159 PM CST Wed Jan 15 2014
Clouds across the CWA continue to thicken and gradually lower late
this evening with sustained WAA as well as approach of upper level
shortwave. Much of the latest guidance...including the RUC and
HRRR...is a bit more enthusiastic about precip during the predawn
hours, so have introduced some MVFR vsbys (with VFR cigs) in light
snow for UIN and STL area TAFS for several hours. Concern also
continues for LLWS. While surface obs suggest that some gustiness
(which will lessen LLWS) should impact UIN believe that the slightly
stronger surface winds will not materialize elsewhere, and as a
result have introduced LLWS at COU and STL area for 1.5-2kft winds
250/45kts. Surface winds will ramp up later Thursday morning and
into the afternoon due to strong pressure gradient from surface low
dropping into Great Lakes, and this combined with fairly deep mixing
should produce west to northwest winds of 20-30kts. Steepening low
level lapse rates combined with a bit of diurnal heating should also
produce CU/SC ceilings of 3-5kft late in the morning and especially
during the afternoon. Very little decrease is expected in wind
speeds heading into Thursday night as the primary cold air surge
enters the region, with occasional snow flurries accompanying the
arrival of the much colder airmass
Specifics for KSTL: Based on above reasoning have introduced some
MVFR vsbys in light snow (with VFR cigs) in the 08-11z time frame,
followed by partial clearing and a threat of LLWS as forecast
soundings are indicating winds of 250/45 kts between 1.5 and 2kft.
Surface winds will slow veer and increase in speed from mid
morning into midday, with west/northwest winds gusting into the
25-30kt range throughout the afternoon. Expecting CU/SC deck
between 3-5kft to accompany the gusty winds and deep mixing.
Truett
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
1201 AM CST Thu Jan 16 2014
.UPDATE:
Issued at 1159 PM CST Wed Jan 15 2014
Made a few changes to the going forecast for the rest of the
night. Short range guidance is trending toward a stronger signal
for some light snow. Showing decent 925-850mb frontogenesis on the
RAP and NAM for the rest of the night ahead of the low level
shortwave, and then another band of frontogenesis higher
up...850-700mb and even some higher than that as the primary 500mb
wave digs across Missouri after 12Z Thursday. Also, upstream
surface obs are showing some light precip under some of the
stronger radar returns over southern Iowa and northwest Missouri.
Have therefore increased PoPs a bit for the rest of the night into
Thursday morning. The lower atmosphere is still pretty dry with
dewpoint depressions of 10-15 degrees and even more in some
spots...so I think that any precip that does reach the ground will
be very light. Have also increased wind speed and gusts on
Thursday. Models are indicating strong gradient winds tomorrow
around 20kts or more with gusts to at least 30kts.
Carney
&&
.SHORT TERM: (Through Late Tonight)
Issued at 321 PM CST Wed Jan 15 2014
Main concern tonight will be chance of light snow. ECMWF/NAM/GFS
are all similar in showing that a shortwave trough currently will
drop out of south central Canada and move into Missouri by 12Z
tomorrow morning. This system will produce some modest ascent
during the late evening and overnight hours, particularly over the
the northeastern half of the area. The main limiting factor will be
dry air in the low levels, so have kept with slight or low chance
pops.
Temperatures will only fall into the lower-mid 20s tonight in the
warm air advection regime. Went lower than MOS guidance as these
values are not much lower than current temperatures.
Britt
.LONG TERM: (Thursday through Next Wednesday)
Issued at 321 PM CST Wed Jan 15 2014
Roller coaster ride to continue with cold front/shortwave trof
exiting forecast area on Thursday. Most of energy to remain just
northeast and east of forecast area. So just have silent slight
chance pops for most of forecast area and low chance pops far
east. With temperatures warming up into the low to mid 40s, the
precipitation may start out as light snow/flurries, but will see
it mixed with light rain/sprinkles during the afternoon hours.
Amounts will be very light, so do not expect any accumulations.
Secondary shortwave, which is a bit stronger, to rotate around
surface low Thursday night. Best chances of light snow will be over
northeast MO...west central/southwestern IL. So have low chance pops
going there...slight chance pops to the west. Little or no
accumulation is expected by early Friday morning with this system.
Lows Thursday night will range from around 9 degrees far north to
around 18 degrees far south.
Surface ridge to build in on Friday with highs only in the upper
teens to mid 20s. Could see some lingering flurries early Friday
morning.
Then surface ridge to move off to the east Friday night as next cold
front approaches region. Lows will be in the mid to upper teens.
Cold front to move through on Saturday with a chance of some light
snow mainly along and east of Mississippi River once again. High
temperatures will range from the low 30s far northeast to low 40s
degrees over central and southern MO. Lows Saturday night will be in
the low to mid 20s.
For the rest of the forecast period, active pattern to continue with
temperatures warming up into the low 40s to low 50s on Sunday ahead
of next cold front that will slide southeast through forecast area
Sunday night. Extended models have differing solutions on placement
and timing of system. For now will keep forecast dry and slightly
cooler temps by Tuesday, in the upper 20s to near 40, then dip down
to mid 20s to mid 30s by Wednesday.
Byrd
&&
.AVIATION: (For the 06z TAFs through 06z Thursday Night)
Issued at 1159 PM CST Wed Jan 15 2014
Clouds across the CWA continue to thicken and gradually lower late
this evening with sustained WAA as well as approach of upper level
shortwave. Much of the latest guidance...including the RUC and
HRRR...is a bit more enthusiastic about precip during the predawn
hours, so have introduced some MVFR vsbys (with VFR cigs) in light
snow for UIN and STL area TAFS for several hours. Concern also
continues for LLWS. While surface obs suggest that some gustiness
(which will lessen LLWS) should impact UIN believe that the slightly
stronger surface winds will not materialize elsewhere, and as a
result have introduced LLWS at COU and STL area for 1.5-2kft winds
250/45kts. Surface winds will ramp up later Thursday morning and
into the afternoon due to strong pressure gradient from surface low
dropping into Great Lakes, and this combined with fairly deep mixing
should produce west to northwest winds of 20-30kts. Steepening low
level lapse rates combined with a bit of diurnal heating should also
produce CU/SC ceilings of 3-5kft late in the morning and especially
during the afternoon. Very little decrease is expected in wind
speeds heading into Thursday night as the primary cold air surge
enters the region, with occasional snow flurries accompanying the
arrival of the much colder airmass
Specifics for KSTL: Based on above reasoning have introduced some
MVFR vsbys in light snow (with VFR cigs) in the 08-11z time frame,
followed by partial clearing and a threat of LLWS as forecast
soundings are indicating winds of 250/45 kts between 1.5 and 2kft.
Surface winds will slow veer and increase in speed from mid
morning into midday, with west/northwest winds gusting into the
25-30kt range throughout the afternoon. Expecting CU/SC deck
between 3-5kft to accompany the gusty winds and deep mixing.
Truett
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
257 PM EST THU JAN 16 2014
.SYNOPSIS...
SCATTERED SNOW SHOWERS WILL END BY AFTERNOON OVER THE SUSQUEHANNA
REGION AND CATSKILLS OF NEW YORK AND NORTHEAST PENNSYLVANIA...WITH
HIGH PRESSURE BRINGING PARTLY SUNNY SKIES TO MOST OF THE REGION
THIS AFTERNOON. A SERIES OF UPPER LEVEL DISTURBANCES WILL PASS THE
REGION THURSDAY NIGHT INTO THE WEEKEND...WITH OCCASIONAL FLURRIES
AND SNOW SHOWERS. HOWEVER...NO SIGNIFICANT SNOW ACCUMULATIONS ARE
EXPECTED AT THIS TIME.
&&
.NEAR TERM /THROUGH TONIGHT/...
950 AM UPDATE...
SNOW SHOWERS STILL LINGERING ACRS ERN ZONES AND FLURRIES ARE NOW
OCCURRING ALONG THE I-81 CORRIDOR. THUS HV EXPANDED FLURRIES BACK
TO THE WEST AND EXPECT THESE SHUD DIMINISH BY 18Z AS DRIER LOW-LVL
AIR WORKS IN.
HV ADJUSTED SKY GRIDS TO BE A LITTLE MORE PESSIMISTIC WITH CLRNG
AS 12Z RAOB FM KBUF INDICATED SATD LYR ARND 800MB. HV FOLLOWED
850-700MB RH FIELDS FM RUC TO GET A BETTER HANDLE ON TIMING WITH
AREAS ALONG I-81 RMNG MOCLDY THRU 16Z AND THEN SLOWLY PROGRESSING
EAST FM THERE. THUS, LOWERED MAX TEMPS BY A DEGREE OR TWO WITH
CLRNG DELAYED. NO OTHER CHGS NEEDED AT THIS TIME.
PREV DISCO BLO...
SCT -SHSN CONTINUE ACRS ERN ZONES. WATER VAPOR SHOW THE UPR LVL
TROF MAKING SLOW EWD PROGRESS AND THIS WILL BRING THIS ACTIVITY TO
AN END LATER THIS MRNG. WEAK SFC RIDGE WILL ALLOW MOST AREAS TO SEE
PARTLY SUNNY SKIES THIS AFTN WITH MAXES GNRLY IN THE L/M30S.
BROADENING TROF OVER THE ERN U.S. WITH SVRL S/WV`S HELPING TO CARVE
OUT THIS FEATURE. INITIAL S/WV AND SFC LOW WILL TRACK NEWD ACRS
THE CNTRL GTLAKES ON FRI...KEEPING BEST SYNOPTIC MSTR TO OUR NW.
SLGT CHC POPS AFTER 06Z FOR THE POTNL OF SOME FLURRIES MOVG INTO
THE REGION DUE TO THIS FEATURE. MINS MAINLY IN THE M20S.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AMPLIFICATION OF THE ERN U.S. TROF CONTINUES. NEXT S/WV MOVS THRU
LATE FRI NGT/SAT MRNG WITH HINTS OF A WEAK SFC LOW TRACKING ACRS
PA. GOOD FORCING WITH THIS COMPACT SYSTEM IN THE QVEC AND DEF
FIELDS. NXT S/WV APRCHS SAT NGT. NAM/GEM TRACK THIS SYSTEM INTO
THE TN VLY WITH SFC LOW TRACKING ACRS THE MID ATLC
STATES...SUGGESTING THIS SYSTEM WOULD BE TOO FAR SOUTH TO HAVE SIG
EFFECTS ON THE BGM CWA. THE GFS/EURO SUGGEST A MORE NRLY TRACK AND
INDICATE POTNL FOR -SHSN AND LGT ACCUMS WITH THIS SYSTEM...AND WE
LEANED IN THAT DIRECTION. WE DO NOTE THAT CONFIDENCE ON TIMING AND
EXACT TRACK OF THESE SYSTEMS IS ON THE LOW SIDE AT THIS TIME RNG.
IF ONE OF THESE S/WV`S AMPLIFIES MORE THAN CRNTLY INDICATED...WE
COULD SEE A FEW INCHES OF ACCUM WITH THEM. AT THIS TIME THE BEST
POTNL WOULD APPEAR TO BE LATE FRI NGT/SAT MRNG ACRS THE POCONOS
AND SRN CATSKILLS.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
300 PM EST UPDATE...
A VERY ACTIVE AND INTERESTING FORECAST IS EXPECTED THROUGH THE
EXTENDED. MADE MINOR ADJUSTMENT TO THE PREVIOUS FORECAST.
A RIDGE OVER THE WESTERN CONUS WILL BECOME AMPLIFIED AGAIN SUNDAY
NIGHT INTO MONDAY ALLOWING MULT SHORTWAVE TO SWING THROUGH THE
NORTHEAST THROUGH THE EXTENDED. THESE CLIPPERS WILL BRING COOLER
AIR A CHANCE FOR SNOW SHOWERS FOR NY AND PA. NO SIGNIFICANT
ACCUMULATIONS ARE EXPECTED THROUGH WED.
THE MAIN EXCITEMENT IN THE EXTENDED FORECAST WILL BE DURING THE
TIME PERIOD OF WED/THURS WHEN A PIECE OF ARCTIC AIR BREAKS OFF
FROM THE POLAR VORTEX. 850MB TEMPS WILL FALL TO -25 DEGREES
CELSIUS ON WEDNESDAY AND THURSDAY ACCOMPANIED WITH 1000MB TO 500MB
HEIGHT THICKNESS IN THE 490S. THIS WILL ALLOW TEMPS OVER THE
REGION TO BE QUITE COLD. LOW TEMPS WED AND THURS MORNING WILL BE
QUITE COLD AND FALL TO NEAR OR BELOW ZERO. WINDS WITH THIS ARCTIC
BLAST WILL ARE NOT EXPECTED TO BE AS STRONG AS THE LAST BLAST
THUS... WIND CHILL VALUES ARE NOT EXPECTED TO FALL BELOW -20 ATTM.
MOSTLY CLOUDY SKIES ARE EXPECTED THROUGH THE FORECAST PERIOD.
&&
.AVIATION /20Z THURSDAY THROUGH TUESDAY/...
1255 PM EST UPDATE...
A STUBBORN BAND OF LIGHT SNOW SHOWERS ARE STILL LINGERING OVER
NORTHEAST PENNSYLVANIA AND CENTRAL NY. THESE BANDS WILL HOPEFULLY
DISSIPATE OVER THE NEXT COUPLE OF HOURS. A SURFACE RIDGE IS TRYING
TO BUILD INTO THE AREA TODAY. AS THIS RIDGE BUILDS IN CIGS SHOULD
BECOME VFR AT ALL TAF SITES BY THIS EVENING. WINDS WILL BECOME
VARIABLE AND LIGHT THIS AFTERNOON AND EVENING AS THE HIGH PRESSURE
BECOMES MORE DEVELOPED OVER THE REGION. FRIDAY MORNING ANOTHER STORM
SYSTEM WILL SWING THROUGH THE NORTHEAST BRINGING ANOTHER CHANCE FOR
SNOW. DECIDED TO PUT TEMPO GROUPS IN FOR NOW AS CONFIDENCE IS NOT
HIGH ON THE START TIME OF THIS EVENT. MVFR CONDITIONS MAY BE
POSSIBLE WITH THESE SHOWERS.
OUTLOOK...
FRI NIGHT TO TUES...OCNL RESTRICTIONS FROM -SHSN THRU THE PD...AS
MULTIPLE CLIPPER SYSTEMS MOVE THROUGH.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...PVN
SHORT TERM...
LONG TERM...KAH
AVIATION...KAH
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1256 PM EST THU JAN 16 2014
.SYNOPSIS...
SCATTERED SNOW SHOWERS WILL END BY AFTERNOON OVER THE SUSQUEHANNA
REGION AND CATSKILLS OF NEW YORK AND NORTHEAST PENNSYLVANIA...WITH
HIGH PRESSURE BRINGING PARTLY SUNNY SKIES TO MOST OF THE REGION
THIS AFTERNOON. A SERIES OF UPPER LEVEL DISTURBANCES WILL PASS THE
REGION THURSDAY NIGHT INTO THE WEEKEND...WITH OCCASIONAL FLURRIES
AND SNOW SHOWERS. HOWEVER...NO SIGNIFICANT SNOW ACCUMULATIONS ARE
EXPECTED AT THIS TIME.
&&
.NEAR TERM /THROUGH TONIGHT/...
950 AM UPDATE...
SNOW SHOWERS STILL LINGERING ACRS ERN ZONES AND FLURRIES ARE NOW
OCCURRING ALONG THE I-81 CORRIDOR. THUS HV EXPANDED FLURRIES BACK
TO THE WEST AND EXPECT THESE SHUD DIMINISH BY 18Z AS DRIER LOW-LVL
AIR WORKS IN.
HV ADJUSTED SKY GRIDS TO BE A LITTLE MORE PESSIMISTIC WITH CLRNG
AS 12Z RAOB FM KBUF INDICATED SATD LYR ARND 800MB. HV FOLLOWED
850-700MB RH FIELDS FM RUC TO GET A BETTER HANDLE ON TIMING WITH
AREAS ALONG I-81 RMNG MOCLDY THRU 16Z AND THEN SLOWLY PROGRESSING
EAST FM THERE. THUS, LOWERED MAX TEMPS BY A DEGREE OR TWO WITH
CLRNG DELAYED. NO OTHER CHGS NEEDED AT THIS TIME.
PREV DISCO BLO...
SCT -SHSN CONTINUE ACRS ERN ZONES. WATER VAPOR SHOW THE UPR LVL
TROF MAKING SLOW EWD PROGRESS AND THIS WILL BRING THIS ACTIVITY TO
AN END LATER THIS MRNG. WEAK SFC RIDGE WILL ALLOW MOST AREAS TO SEE
PARTLY SUNNY SKIES THIS AFTN WITH MAXES GNRLY IN THE L/M30S.
BROADENING TROF OVER THE ERN U.S. WITH SVRL S/WV`S HELPING TO CARVE
OUT THIS FEATURE. INITIAL S/WV AND SFC LOW WILL TRACK NEWD ACRS
THE CNTRL GTLAKES ON FRI...KEEPING BEST SYNOPTIC MSTR TO OUR NW.
SLGT CHC POPS AFTER 06Z FOR THE POTNL OF SOME FLURRIES MOVG INTO
THE REGION DUE TO THIS FEATURE. MINS MAINLY IN THE M20S.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AMPLIFICATION OF THE ERN U.S. TROF CONTINUES. NEXT S/WV MOVS THRU
LATE FRI NGT/SAT MRNG WITH HINTS OF A WEAK SFC LOW TRACKING ACRS
PA. GOOD FORCING WITH THIS COMPACT SYSTEM IN THE QVEC AND DEF
FIELDS. NXT S/WV APRCHS SAT NGT. NAM/GEM TRACK THIS SYSTEM INTO
THE TN VLY WITH SFC LOW TRACKING ACRS THE MID ATLC
STATES...SUGGESTING THIS SYSTEM WOULD BE TOO FAR SOUTH TO HAVE SIG
EFFECTS ON THE BGM CWA. THE GFS/EURO SUGGEST A MORE NRLY TRACK AND
INDICATE POTNL FOR -SHSN AND LGT ACCUMS WITH THIS SYSTEM...AND WE
LEANED IN THAT DIRECTION. WE DO NOTE THAT CONFIDENCE ON TIMING AND
EXACT TRACK OF THESE SYSTEMS IS ON THE LOW SIDE AT THIS TIME RNG.
IF ONE OF THESE S/WV`S AMPLIFIES MORE THAN CRNTLY INDICATED...WE
COULD SEE A FEW INCHES OF ACCUM WITH THEM. AT THIS TIME THE BEST
POTNL WOULD APPEAR TO BE LATE FRI NGT/SAT MRNG ACRS THE POCONOS
AND SRN CATSKILLS.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
300 AM UPDATE...
CONFIDENCE INCREASING FOR ARCTIC AIR MASS DESCENDING ON REGION
TUESDAY-WEDNESDAY NEXT WEEK. GFS HAS BEEN TRENDING COLDER AND NOW
JOINS ECMWF IN HAVING 1000-500MB THICKNESSES INTO THE 490S
DECAMETER RANGE BY 12Z WEDNESDAY. FORECAST HIGHS TUESDAY AND
ESPECIALLY WEDNESDAY WERE ADJUSTED COLDER REFLECTING LATEST WPC
GUIDANCE /AND MODEL TRENDS/. FURTHER LOWERING MAY BE NEEDED IF
UPCOMING RUNS CONTINUE DOWN THIS PATH...AS SUGGESTED BY RAW MODEL
00Z GUIDANCE NUMBERS.
AHEAD OF THAT...GENERAL THEME OF LONG TERM PERIOD REMAINS THE
SAME...PASSING CLIPPERS OFFERING OCCASIONAL CHANCES FOR SNOW
SHOWERS AS DISCUSSED BELOW.
PREVIOUS DISCUSSION...
AN ENDLESS LINE IN A PARADE OF CLIPPERS WL AFFECT THE CWA THRU THE
END OF THE EXTNDD. STRONG S/WV WL DROP THRU THE UPR MIDWEST INTO
THE OH VLY FM 00Z-12Z SUNDAY. AS IT HEADS EAST ALONG THE MASON-
DIXON LINE IT WL WEAKEN AND MAY SPREAD LGT SNOW INTO THE AREA SUN
MRNG. HWVR UNCERTAINTY IS ENUF TO KEEP JUST SLGT CHC POPS SOUTH OF
THE STATE LINE WITH THE MAIN CHC EXPECTED TO BE IN LK EFFECT
ZONES.
FAIRLY STRONG CDFNT PROGGED TO MV THRU PER 12Z GFS AND EC DRG THE
DAY SUNDAY. MODELS BEGIN TO DIVERGE BY 12Z MONDAY AS EURO DVLPS SFC
LOW ACRS CWA AND GFS INDICATES JUST A WK TROF MVG THRU. OPTED TO GO
WITH JUST 20 POPS THRU THIS TIME, HIGHER THAN WPC GRIDS INDICATE.
YET ANOTHER WV MVS THRU TUE INTO TUE NGT WITH CHC SNOW SHOWERS THRU
THE END OF THE LONG TERM. 12Z EURO SHOWING SIGNS OF DEEP H5 LOW
DVLPNG ACRS NERN U.S. BY LATE NEXT WEEK WITH THICKNESS VALUES BLO
500DM.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
1255 PM EST UPDATE...
A STUBBORN BAND OF LIGHT SNOW SHOWERS ARE STILL LINGERING OVER
NORTHEAST PENNSYLVANIA AND CENTRAL NY. THESE BANDS WILL HOPEFULLY
DISSIPATE OVER THE NEXT COUPLE OF HOURS. A SURFACE RIDGE IS TRYING
TO BUILD INTO THE AREA TODAY. AS THIS RIDGE BUILDS IN CIGS SHOULD
BECOME VFR AT ALL TAF SITES BY THIS EVENING. WINDS WILL BECOME
VARIABLE AND LIGHT THIS AFTERNOON AND EVENING AS THE HIGH PRESSURE
BECOMES MORE DEVELOPED OVER THE REGION. FRIDAY MORNING ANOTHER STORM
SYSTEM WILL SWING THROUGH THE NORTHEAST BRINGING ANOTHER CHANCE FOR
SNOW. DECIDED TO PUT TEMPO GROUPS IN FOR NOW AS CONFIDENCE IS NOT
HIGH ON THE START TIME OF THIS EVENT. MVFR CONDITIONS MAY BE
POSSIBLE WITH THESE SHOWERS.
OUTLOOK...
FRI NIGHT TO TUES...OCNL RESTRICTIONS FROM -SHSN THRU THE PD...AS
MULTIPLE CLIPPER SYSTEMS MOVE THROUGH.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...PVN
SHORT TERM...
LONG TERM...MDP/PVN
AVIATION...KAH
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
954 AM EST THU JAN 16 2014
.SYNOPSIS...
SCATTERED SNOW SHOWERS WILL END BY AFTERNOON OVER THE SUSQUEHANNA
REGION AND CATSKILLS OF NEW YORK AND NORTHEAST PENNSYLVANIA...WITH
HIGH PRESSURE BRINGING PARTLY SUNNY SKIES TO MOST OF THE REGION
THIS AFTERNOON. A SERIES OF UPPER LEVEL DISTURBANCES WILL PASS THE
REGION THURSDAY NIGHT INTO THE WEEKEND...WITH OCCASIONAL FLURRIES
AND SNOW SHOWERS. HOWEVER...NO SIGNIFICANT SNOW ACCUMULATIONS ARE
EXPECTED AT THIS TIME.
&&
.NEAR TERM /THROUGH TONIGHT/...
950 AM UPDATE...
SNOW SHOWERS STILL LINGERING ACRS ERN ZONES AND FLURRIES ARE NOW
OCCURRING ALONG THE I-81 CORRIDOR. THUS HV EXPANDED FLURRIES BACK
TO THE WEST AND EXPECT THESE SHUD DIMINISH BY 18Z AS DRIER LOW-LVL
AIR WORKS IN.
HV ADJUSTED SKY GRIDS TO BE A LITTLE MORE PESSIMISTIC WITH CLRNG
AS 12Z RAOB FM KBUF INDICATED SATD LYR ARND 800MB. HV FOLLOWED
850-700MB RH FIELDS FM RUC TO GET A BETTER HANDLE ON TIMING WITH
AREAS ALONG I-81 RMNG MOCLDY THRU 16Z AND THEN SLOWLY PROGRESSING
EAST FM THERE. THUS, LOWERED MAX TEMPS BY A DEGREE OR TWO WITH
CLRNG DELAYED. NO OTHER CHGS NEEDED AT THIS TIME.
PREV DISCO BLO...
SCT -SHSN CONTINUE ACRS ERN ZONES. WATER VAPOR SHOW THE UPR LVL
TROF MAKING SLOW EWD PROGRESS AND THIS WILL BRING THIS ACTIVITY TO
AN END LATER THIS MRNG. WEAK SFC RIDGE WILL ALLOW MOST AREAS TO SEE
PARTLY SUNNY SKIES THIS AFTN WITH MAXES GNRLY IN THE L/M30S.
BROADENING TROF OVER THE ERN U.S. WITH SVRL S/WV`S HELPING TO CARVE
OUT THIS FEATURE. INITIAL S/WV AND SFC LOW WILL TRACK NEWD ACRS
THE CNTRL GTLAKES ON FRI...KEEPING BEST SYNOPTIC MSTR TO OUR NW.
SLGT CHC POPS AFTER 06Z FOR THE POTNL OF SOME FLURRIES MOVG INTO
THE REGION DUE TO THIS FEATURE. MINS MAINLY IN THE M20S.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AMPLIFICATION OF THE ERN U.S. TROF CONTINUES. NEXT S/WV MOVS THRU
LATE FRI NGT/SAT MRNG WITH HINTS OF A WEAK SFC LOW TRACKING ACRS
PA. GOOD FORCING WITH THIS COMPACT SYSTEM IN THE QVEC AND DEF
FIELDS. NXT S/WV APRCHS SAT NGT. NAM/GEM TRACK THIS SYSTEM INTO
THE TN VLY WITH SFC LOW TRACKING ACRS THE MID ATLC
STATES...SUGGESTING THIS SYSTEM WOULD BE TOO FAR SOUTH TO HAVE SIG
EFFECTS ON THE BGM CWA. THE GFS/EURO SUGGEST A MORE NRLY TRACK AND
INDICATE POTNL FOR -SHSN AND LGT ACCUMS WITH THIS SYSTEM...AND WE
LEANED IN THAT DIRECTION. WE DO NOTE THAT CONFIDENCE ON TIMING AND
EXACT TRACK OF THESE SYSTEMS IS ON THE LOW SIDE AT THIS TIME RNG.
IF ONE OF THESE S/WV`S AMPLIFIES MORE THAN CRNTLY INDICATED...WE
COULD SEE A FEW INCHES OF ACCUM WITH THEM. AT THIS TIME THE BEST
POTNL WOULD APPEAR TO BE LATE FRI NGT/SAT MRNG ACRS THE POCONOS
AND SRN CATSKILLS.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
300 AM UPDATE...
CONFIDENCE INCREASING FOR ARCTIC AIR MASS DESCENDING ON REGION
TUESDAY-WEDNESDAY NEXT WEEK. GFS HAS BEEN TRENDING COLDER AND NOW
JOINS ECMWF IN HAVING 1000-500MB THICKNESSES INTO THE 490S
DECAMETER RANGE BY 12Z WEDNESDAY. FORECAST HIGHS TUESDAY AND
ESPECIALLY WEDNESDAY WERE ADJUSTED COLDER REFLECTING LATEST WPC
GUIDANCE /AND MODEL TRENDS/. FURTHER LOWERING MAY BE NEEDED IF
UPCOMING RUNS CONTINUE DOWN THIS PATH...AS SUGGESTED BY RAW MODEL
00Z GUIDANCE NUMBERS.
AHEAD OF THAT...GENERAL THEME OF LONG TERM PERIOD REMAINS THE
SAME...PASSING CLIPPERS OFFERING OCCASIONAL CHANCES FOR SNOW
SHOWERS AS DISCUSSED BELOW.
PREVIOUS DISCUSSION...
AN ENDLESS LINE IN A PARADE OF CLIPPERS WL AFFECT THE CWA THRU THE
END OF THE EXTNDD. STRONG S/WV WL DROP THRU THE UPR MIDWEST INTO
THE OH VLY FM 00Z-12Z SUNDAY. AS IT HEADS EAST ALONG THE MASON-
DIXON LINE IT WL WEAKEN AND MAY SPREAD LGT SNOW INTO THE AREA SUN
MRNG. HWVR UNCERTAINTY IS ENUF TO KEEP JUST SLGT CHC POPS SOUTH OF
THE STATE LINE WITH THE MAIN CHC EXPECTED TO BE IN LK EFFECT
ZONES.
FAIRLY STRONG CDFNT PROGGED TO MV THRU PER 12Z GFS AND EC DRG THE
DAY SUNDAY. MODELS BEGIN TO DIVERGE BY 12Z MONDAY AS EURO DVLPS SFC
LOW ACRS CWA AND GFS INDICATES JUST A WK TROF MVG THRU. OPTED TO GO
WITH JUST 20 POPS THRU THIS TIME, HIGHER THAN WPC GRIDS INDICATE.
YET ANOTHER WV MVS THRU TUE INTO TUE NGT WITH CHC SNOW SHOWERS THRU
THE END OF THE LONG TERM. 12Z EURO SHOWING SIGNS OF DEEP H5 LOW
DVLPNG ACRS NERN U.S. BY LATE NEXT WEEK WITH THICKNESS VALUES BLO
500DM.
&&
.AVIATION /15Z THURSDAY THROUGH MONDAY/...
12Z UPDATE...
HIGH PRESSURE RIDGE IS GRADUALLY BUILDING IN...BUT WEAKENING MID
LEVEL FRONT IS STILL YIELDING -SN THIS MORNING KBGM-KAVP...INCLUDING
OCCASIONAL IFR VIS FOR KAVP THROUGH 13Z. SUBSIDENCE INVERSION AND
CONTINUED LIGHT NNW FLOW NEAR THE SURFACE WILL KEEP A LAYER OF
MOISTURE TRAPPED MUCH OF THE MORNING...RESULTING IN PERSISTENT
MVFR TO LOW END VFR CIG. AS SURFACE RIDGE PASSES WEST TO EAST
MIDDAY...EXPECTING BREAKUP OF MVFR TO LOW END VFR CIG AS WINDS GO
LIGHT AND VARIABLE...LINGERING LONGEST FOR KBGM-KAVP. LIGHT SE TO
S WIND TONIGHT. NEW HIGH CLOUD DECK WILL IN ABOVE 10 KFT AGL LATE
EVENING BUT THEN DROPPING CLOSE TO MVFR TOWARDS 12Z FRIDAY AS A
WEAK SYSTEM APPROACHES.
OUTLOOK...
FRI TO MON...OCNL RESTRICTIONS FROM -SHSN THRU THE PD...AS
MULTIPLE CLIPPER SYSTEMS MOVE THROUGH.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...PVN
SHORT TERM...
LONG TERM...MDP/PVN
AVIATION...MDP
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
942 AM EST THU JAN 16 2014
.SYNOPSIS...
A PERSISTENT UPPER TROUGH OVER MUCH OF THE EASTERN U.S. WILL
CONTINUE TO BRING ON AND OFF CHANCES FOR RAIN AND SNOW SHOWERS
THROUGH THE REMAINDER OF THE WEEK AND INTO THE WEEKEND. NO BIG
STORMS ARE ON THE HORIZON...SO ANY RAIN OR SNOW WE DO GET WILL BE ON
THE LIGHT SIDE. TEMPERATURES REMAIN ABOVE NORMAL AS WELL THROUGH AT
LEAST SATURDAY...WITH HIGHS IN THE 30S AND LOWS IN THE 20S.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 941 AM EST THURSDAY...COMPOSITE RADAR LOOP SHOWING LIGHT
SNOW ACROSS SOUTH CENTRAL AND SOUTHERN VERMONT AS WELL AS THE
ALBANY AND THE HUDSON AND MOHAWK VALLEY IN NEW YORK MOVING
NORTHEASTWARD AT THIS TIME...SO WILL KEEP A MENTION OF SNOW IN THE
FORECAST MAINLY FROM THE CHAMPLAIN VALLEY EASTWARD ACROSS VERMONT
AT THIS TIME. AS NOTED BY PREVIOUS FORECASTER...RUC13 MODEL
PICKING UP ON THIS AND THIS STILL LOOKS GOOD. HAVE MADE SOME MINOR
ADJUSTMENTS TO MAX TEMPERATURES IN A FEW LOCATIONS BASED ON THE
THE LATEST GFS LAMP GUIDANCE AND THE 06Z GFS MOS GUIDANCE.
PREVIOUS DISCUSSION FROM 625 AM EST THURSDAY...QUICK MORNING
UPDATE TO INTRODUCE HIGHER POPS FOR SNOW FROM THE CHAMPLAIN VALLEY
EASTWARD THROUGH THE DAY AS MID-LEVEL PV WHICH I MENTIONED IN MY
PREVIOUS DISCUSSION HAS TURNED OUT TO BE A BIT MORE ROBUST THAN
PREVIOUSLY THOUGHT. LATEST RUC13 NOW SHOWS MOISTURE ASSOCIATED
WITH THIS FEATURE STREAMING NORTHWARD THROUGH MOST OF VERMONT
THROUGH MUCH OF THE DAY AND THUS...HAVE INCREASED POPS TO LIKELY
FOR LIGHT SNOW WITH ACCUMULATIONS OF AND INCH OR TWO...MAINLY ON
GRASSY SURFACES. AS THE BEST MOISTURE AND LIFT SLOWLY SHIFTS
EASTWARD...SNOW WILL TAPER OFF THIS EVENING. TEMPS TODAY CONTINUE
TO RUN ABOVE NORMAL WITH AFTERNOON HIGHS IN THE UPPER 20S TO MID
30S EXPECTED.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
AS OF 320 AM EST THURSDAY...BASICALLY RUNNING WITH A PERSISTENCE
FORECAST THROUGH SATURDAY AS THE NORTH COUNTRY REMAINS UNDER THE
INFLUENCE OF A BROAD UPPER TROUGH OVER THE EASTERN CONUS. SEVERAL
WEAK PIECES OF SHORTWAVE ENERGY WILL PASS THROUGH THE UPPER FLOW
INTRODUCING CHANCES FOR SOME LIGHT RAIN/SNOW SHOWERS THROUGH THE
PERIOD...BUT NOTHING REALLY SIGNIFICANT WITH A LACK OF ANY REAL
DEEP MOISTURE. BEST CHANCE FOR PRECIP WILL BE FRIDAY AFTERNOON/NIGHT
AS THE REMNANTS OF A CLIPPER SYSTEM CURRENTLY PRODUCING WIDESPREAD
HIGH WINDS AND SNOW ACROSS PORTIONS OF THE NORTHERN GREAT PLAINS
WEAKENS AFTER MOVING THROUGH THE GREATS LAKES AND TRACKS INTO THE
NORTHEAST. ONLY LOOKING AT SNOW ACCUMS OF A DUSTING TO 2" AT BEST
ESPECIALLY ACROSS THE HIGHER TERRAIN. TEMPS CONTINUE TO RUN ABOVE
NORMAL WITH HIGHS GENERALLY IN THE 30S AND LOWS IN THE UPPER TEENS
TO MID 20S.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 224 AM EST THURSDAY...TONIGHT`S MEDIUM RANGE MODELS MAINTAIN
OVERALL GOOD CONTINUITY DURING THE DAY 4-7 TIME FRAME (SUN-WED)
OFFERING A HIGHLY AMPLIFIED MERIDIONAL PATTERN ACROSS THE LOWER 48
IN SHOWING A MEAN WESTERN CONUS RIDGE AND CORRESPONDING EASTERN
U.S. TROUGH. THE EASTERN TROUGH WILL GRADUALLY AMPLIFY DEEPER AND
COLDER OVER TIME...AT LEAST ACROSS THE NERN QUARTER OF THE NATION
AS A SERIES OF WEAK DISTURBANCES ROTATE THROUGH THE MEAN UPPER
CYCLONIC FLOW. BEING OF CENTRAL CANADIAN ORIGIN...THESE SYSTEMS
WILL BE RATHER MOISTURE STARVED PRODUCING ONLY VERY LIGHT SNOWS
AND/OR FLURRIES/SHSN ACROSS OUR AREA AND DOWNWIND OF THE GREAT
LAKES. NONETHELESS...AT LEAST SOME LIGHT ACCUMULATIONS WILL BE
POSSIBLE ON AND OFF THROUGH THE PERIOD...ESP DURING SUNDAY/SUNDAY
EVENING WHEN THE FIRST OF THESE FEATURES CROSSES OUR REGION. OF
FURTHER INTEREST IS THE FACT THAT THERE IS GROWING CONSENSUS THAT
A MORE CONCERTED PUSH OF ARCTIC AIR MAY MAKE INROADS BACK INTO OUR
REGION BY THE EARLY AND MIDDLE PORTIONS OF NEXT WEEK AS ADDITIONAL
ENERGY DIGS SOUTHWARD. FOR THE SNOW LOVERS OUT THERE...I WISH I
COULD OFFER A POTENTIAL BIGGER STORM SYSTEM OUT THERE ON THE
HORIZON...BUT WITH THE MEAN UPPER TROUGH AXIS LYING NEARLY ATOP
OUR AREA THE GOMEX/WRN ATLANTIC MOISTURE STREAM WILL LIKELY LIE
TOO FAR EAST/OFFSHORE TO BE A SIGNIFICANT PLAYER FOR NOW. HIGHS
GENERALLY IN THE 20S SUN/MON...THEN COLDER BEHIND POLAR FRONT WITH
READINGS IN THE TEENS BY TUESDAY...AND 5 TO 15 ABOVE BY NEXT
WEDNESDAY AS AN INITIAL PROGNOSIS. OVERNIGHT LOWS ON THE MILDER
SIDE OF GUIDANCE MAINLY DUE TO THE LIKELIHOOD OF VARIABLE CLOUD
COVER (5 TO 15 ABOVE SUN/MON NIGHTS...TRENDING COLDER THEREAFTER).
&&
.AVIATION /15Z THURSDAY THROUGH MONDAY/...
THROUGH 12Z FRIDAY...VRB CONDS EXPECTED ACROSS THE AREA OVER THE
NEXT 24 HOURS AS BACK SIDE POST-FRONTAL MOISTURE INTERACTS WITH
TERRAIN TO PRODUCE AREAS OF LIGHT SNOW FROM THE CHAMPLAIN VALLEY
EASTWARD. OUTSIDE A FEW FLURRIES/SHSN MAINLY DRY AT NRN NY
TERMINALS OF KMSS/KSLK/KPBG WHERE MAINLY BKN/OVC VFR BRIEF MVFR
WILL PREVAIL. AT VERMONT TERMINALS BKN/OVC MVFR OCCNL IFR MORE
LIKELY IN PERIODS OF LIGHT SNOW. SNOW SHOULD TAPER OFF AT KBTV BY
18Z OR SO...BUT WILL LIKELY LINGER TO NEAR 00Z AT KRUT/KMPV. WINDS
LIGHT NORTH TO NORTHEASTERLY LESS THAN 10 KTS THROUGH 00Z...THEN
NEARLY CALM OVERNIGHT TONIGHT.
OUTLOOK 12Z FRIDAY THROUGH MONDAY...GENERALLY BKN/OVC VFR/MVFR
CIGS WITH OCCNL PERIODS OF IFR IN OCCNL PERIODS OF STEADIER LIGHT
SNOWS/SHSN. HIGHEST THREAT OF IFR TO OCCUR SUN/SUN NT WITH PASSAGE
OF WEAK LOW PRESSURE SYSTEM.
&&
.EQUIPMENT...
AS OF 320 AM EST THURSDAY...THE KTYX 88D DOPPLER RADAR LOCATED IN
NORTHERN NEW YORK REMAINS OUT OF SERVICE DUE TO A FAILED POWER
SUPPLY. PARTS ARE ON ORDER TO REPAIR THE PROBLEM...HOWEVER
IT MAY TAKE SEVERAL DAYS FOR THEM TO ARRIVE. THUS...THERE IS
NO ESTIMATE AVAILABLE AT THIS TIME AS TO WHEN THE RADAR WILL BE
RESTORED TO FULL SERVICE.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...LAHIFF
NEAR TERM...WGH/LAHIFF
SHORT TERM...LAHIFF
LONG TERM...JMG
AVIATION...JMG
EQUIPMENT...WFO BTV
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
633 AM EST THU JAN 16 2014
.SYNOPSIS...
A PERSISTENT UPPER TROUGH OVER MUCH OF THE EASTERN U.S. WILL
CONTINUE TO BRING ON AND OFF CHANCES FOR RAIN AND SNOW SHOWERS
THROUGH THE REMAINDER OF THE WEEK AND INTO THE WEEKEND. NO BIG
STORMS ARE ON THE HORIZON...SO ANY RAIN OR SNOW WE DO GET WILL BE ON
THE LIGHT SIDE. TEMPERATURES REMAIN ABOVE NORMAL AS WELL THROUGH AT
LEAST SATURDAY...WITH HIGHS IN THE 30S AND LOWS IN THE 20S.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 625 AM EST THURSDAY...QUICK MORNING UPDATE TO INTRODUCE
HIGHER POPS FOR SNOW FROM THE CHAMPLAIN VALLEY EASTWARD THROUGH
THE DAY AS MID-LEVEL PV WHICH I MENTIONED IN MY PREVIOUS
DISCUSSION HAS TURNED OUT TO BE A BIT MORE ROBUST THAN PREVIOUSLY
THOUGHT. LATEST RUC13 NOW SHOWS MOISTURE ASSOCIATED WITH THIS
FEATURE STREAMING NORTHWARD THROUGH MOST OF VERMONT THROUGH MUCH
OF THE DAY AND THUS...HAVE INCREASED POPS TO LIKELY FOR LIGHT SNOW
WITH ACCUMULATIONS OF AND INCH OR TWO...MAINLY ON GRASSY SURFACES.
AS THE BEST MOISTURE AND LIFT SLOWLY SHIFTS EASTWARD...SNOW WILL
TAPER OFF THIS EVENING. TEMPS TODAY CONTINUE TO RUN ABOVE NORMAL
WITH AFTERNOON HIGHS IN THE UPPER 20S TO MID 30S EXPECTED.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
AS OF 320 AM EST THURSDAY...BASICALLY RUNNING WITH A PERSISTENCE
FORECAST THROUGH SATURDAY AS THE NORTH COUNTRY REMAINS UNDER THE
INFLUENCE OF A BROAD UPPER TROUGH OVER THE EASTERN CONUS. SEVERAL
WEAK PIECES OF SHORTWAVE ENERGY WILL PASS THROUGH THE UPPER FLOW
INTRODUCING CHANCES FOR SOME LIGHT RAIN/SNOW SHOWERS THROUGH THE
PERIOD...BUT NOTHING REALLY SIGNIFICANT WITH A LACK OF ANY REAL
DEEP MOISTURE. BEST CHANCE FOR PRECIP WILL BE FRIDAY AFTERNOON/NIGHT
AS THE REMNANTS OF A CLIPPER SYSTEM CURRENTLY PRODUCING WIDESPREAD
HIGH WINDS AND SNOW ACROSS PORTIONS OF THE NORTHERN GREAT PLAINS
WEAKENS AFTER MOVING THROUGH THE GREATS LAKES AND TRACKS INTO THE
NORTHEAST. ONLY LOOKING AT SNOW ACCUMS OF A DUSTING TO 2" AT BEST
ESPECIALLY ACROSS THE HIGHER TERRAIN. TEMPS CONTINUE TO RUN ABOVE
NORMAL WITH HIGHS GENERALLY IN THE 30S AND LOWS IN THE UPPER TEENS
TO MID 20S.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 224 AM EST THURSDAY...TONIGHT`S MEDIUM RANGE MODELS MAINTAIN
OVERALL GOOD CONTINUITY DURING THE DAY 4-7 TIME FRAME (SUN-WED)
OFFERING A HIGHLY AMPLIFIED MERIDIONAL PATTERN ACROSS THE LOWER 48
IN SHOWING A MEAN WESTERN CONUS RIDGE AND CORRESPONDING EASTERN
U.S. TROUGH. THE EASTERN TROUGH WILL GRADUALLY AMPLIFY DEEPER AND
COLDER OVER TIME...AT LEAST ACROSS THE NERN QUARTER OF THE NATION
AS A SERIES OF WEAK DISTURBANCES ROTATE THROUGH THE MEAN UPPER
CYCLONIC FLOW. BEING OF CENTRAL CANADIAN ORIGIN...THESE SYSTEMS
WILL BE RATHER MOISTURE STARVED PRODUCING ONLY VERY LIGHT SNOWS
AND/OR FLURRIES/SHSN ACROSS OUR AREA AND DOWNWIND OF THE GREAT
LAKES. NONETHELESS...AT LEAST SOME LIGHT ACCUMULATIONS WILL BE
POSSIBLE ON AND OFF THROUGH THE PERIOD...ESP DURING SUNDAY/SUNDAY
EVENING WHEN THE FIRST OF THESE FEATURES CROSSES OUR REGION. OF
FURTHER INTEREST IS THE FACT THAT THERE IS GROWING CONSENSUS THAT
A MORE CONCERTED PUSH OF ARCTIC AIR MAY MAKE INROADS BACK INTO OUR
REGION BY THE EARLY AND MIDDLE PORTIONS OF NEXT WEEK AS ADDITIONAL
ENERGY DIGS SOUTHWARD. FOR THE SNOW LOVERS OUT THERE...I WISH I
COULD OFFER A POTENTIAL BIGGER STORM SYSTEM OUT THERE ON THE
HORIZON...BUT WITH THE MEAN UPPER TROUGH AXIS LYING NEARLY ATOP
OUR AREA THE GOMEX/WRN ATLANTIC MOISTURE STREAM WILL LIKELY LIE
TOO FAR EAST/OFFSHORE TO BE A SIGNIFICANT PLAYER FOR NOW. HIGHS
GENERALLY IN THE 20S SUN/MON...THEN COLDER BEHIND POLAR FRONT WITH
READINGS IN THE TEENS BY TUESDAY...AND 5 TO 15 ABOVE BY NEXT
WEDNESDAY AS AN INITIAL PROGNOSIS. OVERNIGHT LOWS ON THE MILDER
SIDE OF GUIDANCE MAINLY DUE TO THE LIKELIHOOD OF VARIABLE CLOUD
COVER (5 TO 15 ABOVE SUN/MON NIGHTS...TRENDING COLDER THEREAFTER).
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
THROUGH 12Z FRIDAY...VRB CONDS EXPECTED ACROSS THE AREA OVER THE
NEXT 24 HOURS AS BACK SIDE POST-FRONTAL MOISTURE INTERACTS WITH
TERRAIN TO PRODUCE AREAS OF LIGHT SNOW FROM THE CHAMPLAIN VALLEY
EASTWARD. OUTSIDE A FEW FLURRIES/SHSN MAINLY DRY AT NRN NY
TERMINALS OF KMSS/KSLK/KPBG WHERE MAINLY BKN/OVC VFR BRIEF MVFR
WILL PREVAIL. AT VERMONT TERMINALS BKN/OVC MVFR OCCNL IFR MORE
LIKELY IN PERIODS OF LIGHT SNOW. SNOW SHOULD TAPER OFF AT KBTV BY
18Z OR SO...BUT WILL LIKELY LINGER TO NEAR 00Z AT KRUT/KMPV. WINDS
LIGHT NORTH TO NORTHEASTERLY LESS THAN 10 KTS THROUGH 00Z...THEN
NEARLY CALM OVERNIGHT TONIGHT.
OUTLOOK 12Z FRIDAY THROUGH MONDAY...GENERALLY BKN/OVC VFR/MVFR
CIGS WITH OCCNL PERIODS OF IFR IN OCCNL PERIODS OF STEADIER LIGHT
SNOWS/SHSN. HIGHEST THREAT OF IFR TO OCCUR SUN/SUN NT WITH PASSAGE
OF WEAK LOW PRESSURE SYSTEM.
&&
.EQUIPMENT...
AS OF 320 AM EST THURSDAY...THE KTYX 88D DOPPLER RADAR LOCATED IN
NORTHERN NEW YORK REMAINS OUT OF SERVICE DUE TO A FAILED POWER
SUPPLY. PARTS ARE ON ORDER TO REPAIR THE PROBLEM...HOWEVER
IT MAY TAKE SEVERAL DAYS FOR THEM TO ARRIVE. THUS...THERE IS
NO ESTIMATE AVAILABLE AT THIS TIME AS TO WHEN THE RADAR WILL BE
RESTORED TO FULL SERVICE.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...LAHIFF
NEAR TERM...LAHIFF
SHORT TERM...LAHIFF
LONG TERM...JMG
AVIATION...JMG
EQUIPMENT...WFO BTV
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
625 AM EST THU JAN 16 2014
.SYNOPSIS...
A PERSISTENT UPPER TROUGH OVER MUCH OF THE EASTERN U.S. WILL
CONTINUE TO BRING ON AND OFF CHANCES FOR RAIN AND SNOW SHOWERS
THROUGH THE REMAINDER OF THE WEEK AND INTO THE WEEKEND. NO BIG
STORMS ARE ON THE HORIZON...SO ANY RAIN OR SNOW WE DO GET WILL BE ON
THE LIGHT SIDE. TEMPERATURES REMAIN ABOVE NORMAL AS WELL THROUGH AT
LEAST SATURDAY...WITH HIGHS IN THE 30S AND LOWS IN THE 20S.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 625 AM EST THURSDAY...QUICK MORNING UPDATE TO INTRODUCE
HIGHER POPS FOR SNOW FROM THE CHAMPLAIN VALLEY EASTWARD THROUGH
THE DAY AS MID-LEVEL PV WHICH I MENTIONED IN MY PREVIOUS
DISCUSSION HAS TURNED OUT TO BE A BIT MORE ROBUST THAN PREVIOUSLY
THOUGHT. LATEST RUC13 NOW SHOWS MOISTURE ASSOCIATED WITH THIS
FEATURE STREAMING NORTHWARD THROUGH MOST OF VERMONT THROUGH MUCH
OF THE DAY AND THUS...HAVE INCREASED POPS TO LIKELY FOR LIGHT SNOW
WITH ACCUMULATIONS OF AND INCH OR TWO...MAINLY ON GRASSY SURFACES.
AS THE BEST MOISTURE AND LIFT SLOWLY SHIFTS EASTWARD...SNOW WILL
TAPER OFF THIS EVENING. TEMPS TODAY CONTINUE TO RUN ABOVE NORMAL
WITH AFTERNOON HIGHS IN THE UPPER 20S TO MID 30S EXPECTED.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
AS OF 320 AM EST THURSDAY...BASICALLY RUNNING WITH A PERSISTENCE
FORECAST THROUGH SATURDAY AS THE NORTH COUNTRY REMAINS UNDER THE
INFLUENCE OF A BROAD UPPER TROUGH OVER THE EASTERN CONUS. SEVERAL
WEAK PIECES OF SHORTWAVE ENERGY WILL PASS THROUGH THE UPPER FLOW
INTRODUCING CHANCES FOR SOME LIGHT RAIN/SNOW SHOWERS THROUGH THE
PERIOD...BUT NOTHING REALLY SIGNIFICANT WITH A LACK OF ANY REAL
DEEP MOISTURE. BEST CHANCE FOR PRECIP WILL BE FRIDAY AFTERNOON/NIGHT
AS THE REMNANTS OF A CLIPPER SYSTEM CURRENTLY PRODUCING WIDESPREAD
HIGH WINDS AND SNOW ACROSS PORTIONS OF THE NORTHERN GREAT PLAINS
WEAKENS AFTER MOVING THROUGH THE GREATS LAKES AND TRACKS INTO THE
NORTHEAST. ONLY LOOKING AT SNOW ACCUMS OF A DUSTING TO 2" AT BEST
ESPECIALLY ACROSS THE HIGHER TERRAIN. TEMPS CONTINUE TO RUN ABOVE
NORMAL WITH HIGHS GENERALLY IN THE 30S AND LOWS IN THE UPPER TEENS
TO MID 20S.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 224 AM EST THURSDAY...TONIGHT`S MEDIUM RANGE MODELS MAINTAIN
OVERALL GOOD CONTINUITY DURING THE DAY 4-7 TIME FRAME (SUN-WED)
OFFERING A HIGHLY AMPLIFIED MERIDIONAL PATTERN ACROSS THE LOWER 48
IN SHOWING A MEAN WESTERN CONUS RIDGE AND CORRESPONDING EASTERN
U.S. TROUGH. THE EASTERN TROUGH WILL GRADUALLY AMPLIFY DEEPER AND
COLDER OVER TIME...AT LEAST ACROSS THE NERN QUARTER OF THE NATION
AS A SERIES OF WEAK DISTURBANCES ROTATE THROUGH THE MEAN UPPER
CYCLONIC FLOW. BEING OF CENTRAL CANADIAN ORIGIN...THESE SYSTEMS
WILL BE RATHER MOISTURE STARVED PRODUCING ONLY VERY LIGHT SNOWS
AND/OR FLURRIES/SHSN ACROSS OUR AREA AND DOWNWIND OF THE GREAT
LAKES. NONETHELESS...AT LEAST SOME LIGHT ACCUMULATIONS WILL BE
POSSIBLE ON AND OFF THROUGH THE PERIOD...ESP DURING SUNDAY/SUNDAY
EVENING WHEN THE FIRST OF THESE FEATURES CROSSES OUR REGION. OF
FURTHER INTEREST IS THE FACT THAT THERE IS GROWING CONSENSUS THAT
A MORE CONCERTED PUSH OF ARCTIC AIR MAY MAKE INROADS BACK INTO OUR
REGION BY THE EARLY AND MIDDLE PORTIONS OF NEXT WEEK AS ADDITIONAL
ENERGY DIGS SOUTHWARD. FOR THE SNOW LOVERS OUT THERE...I WISH I
COULD OFFER A POTENTIAL BIGGER STORM SYSTEM OUT THERE ON THE
HORIZON...BUT WITH THE MEAN UPPER TROUGH AXIS LYING NEARLY ATOP
OUR AREA THE GOMEX/WRN ATLANTIC MOISTURE STREAM WILL LIKELY LIE
TOO FAR EAST/OFFSHORE TO BE A SIGNIFICANT PLAYER FOR NOW. HIGHS
GENERALLY IN THE 20S SUN/MON...THEN COLDER BEHIND POLAR FRONT WITH
READINGS IN THE TEENS BY TUESDAY...AND 5 TO 15 ABOVE BY NEXT
WEDNESDAY AS AN INITIAL PROGNOSIS. OVERNIGHT LOWS ON THE MILDER
SIDE OF GUIDANCE MAINLY DUE TO THE LIKELIHOOD OF VARIABLE CLOUD
COVER (5 TO 15 ABOVE SUN/MON NIGHTS...TRENDING COLDER THEREAFTER).
&&
.AVIATION /11Z THURSDAY THROUGH MONDAY/...
THROUGH 06Z FRIDAY...GENERALLY BKN/OVC VFR/MVFR CONDS ACROSS THE
AREA OVER THE NEXT 24 HOURS. EXCEPTION WILL BE SOME BRIEF IFR AT
KMPV THROUGH 12Z...AND AGAIN LATER THIS AFTERNOON/EVENING. LINGERING
MOISTURE AND A WEAK RIPPLE OR TWO IN THE SOUTHWEST FLOW ALOFT WILL
KEEP THE THREAT OF LIGHT SNOW ACROSS VT TERMINALS THROUGH MID
TO LATE AFTERNOON...THOUGH MAINLY DRY AT NRN NY TERMINALS TO THE
WEST OF THIS DEEPER MOISTURE. SOME DRY PERIODS AS WELL. CAN`T
RULE OUT SOME IFR FOR A FEW HOURS LATER THIS AFTERNOON...MAINLY AT
KMPV...BUT AGAIN BKN/OVC VFR/MVFR CIGS GENERALLY THE RULE. WINDS
LIGHT NORTH TO NORTHEASTERLY MAINLY 5 KTS OR LESS.
OUTLOOK 06Z FRIDAY THROUGH MONDAY...
A TROF OF LOW PRES WL CONT TO DEVELOP ACRS OUR TAF SITES WITH
PERIODS OF SNOW SHOWERS. THE BEST CHCS FOR OCCASIONAL IFR VIS/CIGS
WL BE AT SLK/MPV ASSOCIATED WITH THE HEAVIER SNOW SHOWERS.
OTHERWISE...VFR WITH BRIEF PERIODS OF MVFR CONDITIONS WL BE
EXPECTED AT MSS/BTV/RUT/PBG.
&&
.EQUIPMENT...
AS OF 320 AM EST THURSDAY...THE KTYX 88D DOPPLER RADAR LOCATED IN
NORTHERN NEW YORK REMAINS OUT OF SERVICE DUE TO A FAILED POWER
SUPPLY. PARTS ARE ON ORDER TO REPAIR THE PROBLEM...HOWEVER
IT MAY TAKE SEVERAL DAYS FOR THEM TO ARRIVE. THUS...THERE IS
NO ESTIMATE AVAILABLE AT THIS TIME AS TO WHEN THE RADAR WILL BE
RESTORED TO FULL SERVICE.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...LAHIFF
NEAR TERM...LAHIFF
SHORT TERM...LAHIFF
LONG TERM...JMG
AVIATION...JMG/MUCCILLI
EQUIPMENT...WFO BTV
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
320 AM EST THU JAN 16 2014
.SYNOPSIS...
A PERSISTENT UPPER TROUGH OVER MUCH OF THE EASTERN U.S. WILL
CONTINUE TO BRING ON AND OFF CHANCES FOR RAIN AND SNOW SHOWERS
THROUGH THE REMAINDER OF THE WEEK AND INTO THE WEEKEND. NO BIG
STORMS ARE ON THE HORIZON...SO ANY RAIN OR SNOW WE DO GET WILL BE ON
THE LIGHT SIDE. TEMPERATURES REMAIN ABOVE NORMAL AS WELL THROUGH AT
LEAST SATURDAY...WITH HIGHS IN THE 30S AND LOWS IN THE 20S.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 320 AM EST THURSDAY...GENERALLY QUIET WEATHER IS EXPECTED
ACROSS THE NORTH COUNTRY TODAY AS A SURFACE COLD FRONT EXITS TO
OUR EAST AND A WEAK AREA OF SURFACE HIGH PRESSURE OFF TO OUR
SOUTHWEST TRIES TO NUDGE NORTHEASTWARD INTO THE REGION. STILL
NOTING THOUGH AN ELONGATED AREA OF ENHANCED PV BEHIND THE FRONT ON
LATEST WV ANALYSIS WITH SOME LIGHT ECHOES ON CURRENT RADAR
SOUTHWEST OF GLENS FALLS DOWN INTO CENTRAL PA. LATEST RUC BASED
MODELS SUCH AS THE HRRR/RUC13 AND LOCAL 6KM WRF HANDLING CURRENT
CONDITIONS VERY WELL AND SHOW THE POTENTIAL FOR SOME OF THE
UPSTREAM ENERGY TO PEAL OFF THROUGH CENTRAL AND EASTERN VERMONT
THROUGH THE DAY...SO HAVE KEPT IN SOME LOW CHANCE POPS FOR SNOW
SHOWERS. TEMPS TODAY CONTINUE TO RUN ABOVE NORMAL WITH AFTERNOON
HIGHS IN THE UPPER 20S TO MID 30S EXPECTED.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
AS OF 320 AM EST THURSDAY...BASICALLY RUNNING WITH A PERSISTENCE
FORECAST THROUGH SATURDAY AS THE NORTH COUNTRY REMAINS UNDER THE
INFLUENCE OF A BROAD UPPER TROUGH OVER THE EASTERN CONUS. SEVERAL
WEAK PIECES OF SHORTWAVE ENERGY WILL PASS THROUGH THE UPPER FLOW
INTRODUCING CHANCES FOR SOME LIGHT RAIN/SNOW SHOWERS THROUGH THE
PERIOD...BUT NOTHING REALLY SIGNIFICANT WITH A LACK OF ANY REAL
DEEP MOISTURE. BEST CHANCE FOR PRECIP WILL BE FRIDAY AFTERNOON/NIGHT
AS THE REMNANTS OF A CLIPPER SYSTEM CURRENTLY PRODUCING WIDESPREAD
HIGH WINDS AND SNOW ACROSS PORTIONS OF THE NORTHERN GREAT PLAINS
WEAKENS AFTER MOVING THROUGH THE GREATS LAKES AND TRACKS INTO THE
NORTHEAST. ONLY LOOKING AT SNOW ACCUMS OF A DUSTING TO 2" AT BEST
ESPECIALLY ACROSS THE HIGHER TERRAIN. TEMPS CONTINUE TO RUN ABOVE
NORMAL WITH HIGHS GENERALLY IN THE 30S AND LOWS IN THE UPPER TEENS
TO MID 20S.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 224 AM EST THURSDAY...TONIGHT`S MEDIUM RANGE MODELS MAINTAIN
OVERALL GOOD CONTINUITY DURING THE DAY 4-7 TIME FRAME (SUN-WED)
OFFERING A HIGHLY AMPLIFIED MERIDIONAL PATTERN ACROSS THE LOWER 48
IN SHOWING A MEAN WESTERN CONUS RIDGE AND CORRESPONDING EASTERN
U.S. TROUGH. THE EASTERN TROUGH WILL GRADUALLY AMPLIFY DEEPER AND
COLDER OVER TIME...AT LEAST ACROSS THE NERN QUARTER OF THE NATION
AS A SERIES OF WEAK DISTURBANCES ROTATE THROUGH THE MEAN UPPER
CYCLONIC FLOW. BEING OF CENTRAL CANADIAN ORIGIN...THESE SYSTEMS
WILL BE RATHER MOISTURE STARVED PRODUCING ONLY VERY LIGHT SNOWS
AND/OR FLURRIES/SHSN ACROSS OUR AREA AND DOWNWIND OF THE GREAT
LAKES. NONETHELESS...AT LEAST SOME LIGHT ACCUMULATIONS WILL BE
POSSIBLE ON AND OFF THROUGH THE PERIOD...ESP DURING SUNDAY/SUNDAY
EVENING WHEN THE FIRST OF THESE FEATURES CROSSES OUR REGION. OF
FURTHER INTEREST IS THE FACT THAT THERE IS GROWING CONSENSUS THAT
A MORE CONCERTED PUSH OF ARCTIC AIR MAY MAKE INROADS BACK INTO OUR
REGION BY THE EARLY AND MIDDLE PORTIONS OF NEXT WEEK AS ADDITIONAL
ENERGY DIGS SOUTHWARD. FOR THE SNOW LOVERS OUT THERE...I WISH I
COULD OFFER A POTENTIAL BIGGER STORM SYSTEM OUT THERE ON THE
HORIZON...BUT WITH THE MEAN UPPER TROUGH AXIS LYING NEARLY ATOP
OUR AREA THE GOMEX/WRN ATLANTIC MOISTURE STREAM WILL LIKELY LIE
TOO FAR EAST/OFFSHORE TO BE A SIGNIFICANT PLAYER FOR NOW. HIGHS
GENERALLY IN THE 20S SUN/MON...THEN COLDER BEHIND POLAR FRONT WITH
READINGS IN THE TEENS BY TUESDAY...AND 5 TO 15 ABOVE BY NEXT
WEDNESDAY AS AN INITIAL PROGNOSIS. OVERNIGHT LOWS ON THE MILDER
SIDE OF GUIDANCE MAINLY DUE TO THE LIKELIHOOD OF VARIABLE CLOUD
COVER (5 TO 15 ABOVE SUN/MON NIGHTS...TRENDING COLDER THEREAFTER).
&&
.AVIATION /08Z THURSDAY THROUGH MONDAY/...
THROUGH 06Z FRIDAY...GENERALLY BKN/OVC VFR/MVFR CONDS ACROSS THE
AREA OVER THE NEXT 24 HOURS. EXCEPTION WILL BE SOME BRIEF IFR AT
KMPV THROUGH 12Z...AND AGAIN LATER THIS AFTERNOON/EVENING. LINGERING
MOISTURE AND A WEAK RIPPLE OR TWO IN THE SOUTHWEST FLOW ALOFT WILL
KEEP THE THREAT OF LIGHT SNOW ACROSS VT TERMINALS THROUGH MID
TO LATE AFTERNOON...THOUGH MAINLY DRY AT NRN NY TERMINALS TO THE
WEST OF THIS DEEPER MOISTURE. SOME DRY PERIODS AS WELL. CAN`T
RULE OUT SOME IFR FOR A FEW HOURS LATER THIS AFTERNOON...MAINLY AT
KMPV...BUT AGAIN BKN/OVC VFR/MVFR CIGS GENERALLY THE RULE. WINDS
LIGHT NORTH TO NORTHEASTERLY MAINLY 5 KTS OR LESS.
OUTLOOK 06Z FRIDAY THROUGH MONDAY...
A TROF OF LOW PRES WL CONT TO DEVELOP ACRS OUR TAF SITES WITH
PERIODS OF SNOW SHOWERS. THE BEST CHCS FOR OCCASIONAL IFR VIS/CIGS
WL BE AT SLK/MPV ASSOCIATED WITH THE HEAVIER SNOW SHOWERS.
OTHERWISE...VFR WITH BRIEF PERIODS OF MVFR CONDITIONS WL BE
EXPECTED AT MSS/BTV/RUT/PBG.
&&
.EQUIPMENT...
AS OF 320 AM EST THURSDAY...THE KTYX 88D DOPPLER RADAR LOCATED IN
NORTHERN NEW YORK REMAINS OUT OF SERVICE DUE TO A FAILED POWER
SUPPLY. PARTS ARE ON ORDER TO REPAIR THE PROBLEM...HOWEVER
IT MAY TAKE SEVERAL DAYS FOR THEM TO ARRIVE. THUS...THERE IS
NO ESTIMATE AVAILABLE AT THIS TIME AS TO WHEN THE RADAR WILL BE
RESTORED TO FULL SERVICE.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...LAHIFF
NEAR TERM...LAHIFF
SHORT TERM...LAHIFF
LONG TERM...JMG
AVIATION...JMG/MUCCILLI
EQUIPMENT...WFO BTV
AREA FORECAST DISCUSSION
NWS RALEIGH NC
142 PM EST THU JAN 16 2014
.SYNOPSIS...HIGH PRESSURE BRIEFLY BUILDS OVER THE REGION TONIGHT...
BEFORE MOVING OFF THE COAST EARLY FRIDAY. ANOTHER COLD FRONT CROSSES
THE REGION FRIDAY AFTERNOON THROUGH FRIDAY NIGHT. HIGH PRESSURE
BRIEFLY BUILDS IN AGAIN FOR SATURDAY AHEAD OF YET ANOTHER COLD FRONT
THAT APPROACHES FROM THE WEST SATURDAY NIGHT.
&&
.NEAR TERM /TODAY THROUGH FRIDAY NIGHT/...
AS OF 940 AM THURSDAY...
A DRY AIR ON WATER VAPOR IMAGERY WAS MOVING IN FROM THE SOUTHWEST...
LINGERING PRECIPITATION MAINLY IN THE NORTHERN COASTAL PLAIN WAS
DIMINISHING ON RADAR AND MOVING OFF TO THE EAST AND NORTHEAST. THE
CLEARING LINE WAS ABOUT AS FAR EAST AS U.S. 1...AND THE CLEARING
COULD BE SLOW FOR THE NEXT FEW HOURS AS THE RAP SOUNDINGS AND ITS
LOW-LEVEL MOISTURE FORECAST...PLUS THE LOW CLOUD FORECAST FROM THE
HRRR WRF...INDICATE ONLY GRADUAL DRYING OF THE BOUNDARY LAYER FROM
WEST TO EAST. SKIES SHOULD BECOME PARTLY SUNNY IN THE U.S. 1
CORRIDOR FOR THE REST OF THE MORNING INTO THE EARLY AFTERNOON... BUT
IT MAY TAKE INTO MID-AFTERNOON OR SO IN MANY PART OF THE COASTAL
PLAIN...ESPECIALLY NORTH OF GOLDSBORO. LEFT MAXIMUM TEMPERATURES
ABOUT AS IS ON THE COOL SIDE OF GUIDANCE...WARMING A CATEGORY IN THE
TRIAD UNDER GOOD SUN AND WHERE KGSO HAS WARMED QUICKLY INTO THE
UPPER 30S. -DJF
THE SURFACE RIDGE CENTERED OVER THE CENTRAL GULF COAST AND NOSING
ACROSS NC LATER TODAY SLIPS QUICKLY TO OUR SE TONIGHT... AND EXPECT
FAIR SKIES WITH N WIND BACKING AROUND TO W AND SW OVERNIGHT....
LEADING TO STEADY OR SLIGHTLY RISING THICKNESSES LATE WITH THE ONSET
OF LOW LEVEL WARM AIR ADVECTION WITHIN THE RETURN FLOW. HAVE BUMPED
LOWS UP A DEGREE OR SO TO 27-30.
FOR FRI/FRI NIGHT: SOUTHWEST FLOW AHEAD OF THE NEXT CLIPPER COLD
FRONT SHOULD MAKE FOR A RATHER SEASONABLE DAY AS THICKNESSES WILL BE
CLOSE TO NORMALS. EXPECT PLENTY OF SUNSHINE WITH NO GOOD FEED OF
MOISTURE INTO THE AREA AT ANY LEVEL... ALTHOUGH A DECK OF MOSTLY MID
CLOUDS ASSOCIATED WITH THE APPROACHING MID LEVEL TROUGH AXIS IS
EXPECTED LATE FRI INTO FRI NIGHT GIVEN HEIGHT FALLS AROUND 100-120
M. OVERALL THE COLUMN SHOULD BE TOO DRY TO SUPPORT PRECIP DESPITE
THE HEIGHT FALLS AND MODEST UPPER DIVERGENCE AND DPVA. HIGHS AROUND
50 TO 55... A LITTLE ABOVE NORMAL. EXPECT TEMPS TO FALL BACK INTO
THE MID 20S FRI NIGHT WITH GOOD COLD AIR ADVECTION. -GIH
&&
.SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/...
AS OF 130 PM THURSDAY...
SATURDAY AND SATURDAY NIGHT: THE SYNOPTIC PATTERN WILL REMAIN ACTIVE
(ALBEIT DRY) IN ASSOC/W A PERSISTENT UPPER LEVEL TROUGH OVER THE
EASTERN CONUS. SENSIBLE WEATHER WILL BE DICTATED PRIMARILY BY A
`FINAL` ROUND OF SHORTWAVE ENERGY /DPVA/ AND AN ASSOCIATED CLIPPER-
TYPE SFC LOW APPROACHING THE REGION FROM THE NW ON SAT BEFORE
TRACKING EAST ACROSS THE MID-ATLANTIC SAT NIGHT. THE LATEST 12Z
MODEL GUIDANCE REMAINS DRY FOR CENTRAL NC...WHICH MAKES SENSE GIVEN
THE FAST MOVING NATURE OF THE SYSTEM (LITTLE CHANCE FOR MOISTURE
RECOVERY) AND THAT THE BEST DPVA /LAYER-LIFTING/ WILL OCCUR WELL TO
THE NORTH IN VICINITY OF THE MASON DIXON LINE. EXPECT BELOW NORMAL
HIGHS IN THE UPPER 30S TO LOWER 40S ON SATURDAY IN ASSOC/W COLD
ADVECTION IN THE WAKE OF A PRIOR SHORTWAVE/CLIPPER LOW AND ATTENDANT
DRY COLD FRONTAL PASSAGE FRI NIGHT. ONE WOULD THINK TEMPERATURES SAT
NIGHT WOULD HAVE A DIFFICULT TIME FALLING GIVEN A TIGHTENING MSLP
GRADIENT AND SOUTHERLY FLOW IN ADVANCE OF THE NEXT CLIPPER LOW
APPROACHING FROM THE NW...THOUGH EVEN SEVERAL HOURS OF RADIATIONAL
COOLING AFTER SUNSET COULD EASILY ALLOW TEMPS TO FALL INTO THE 20S
GIVEN THE AIRMASS IN PLACE. GIVEN THE TRACK OF THE SHORTWAVE AND
ASSOC CLIPPER LOW WILL BE WELL NORTH... ANTICIPATE THAT A RELATIVELY
TIGHT MSLP GRADIENT /SOUTHERLY FLOW/ WILL ONLY ALLOW FOR LOWS IN THE
UPPER 20S TO LOWER 30S...PERHAPS IN THE LOWER/MID 30S IF A SOUTHERLY
BREEZE IS PRESENT MOST OF THE EVENING/NIGHT. -VINCENT
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 145 PM THURSDAY...
THE LATEST LONG RANGE GUIDANCE CONTINUES TO INDICATE A BRIEF RETURN
TO A MORE ZONAL FLOW ALOFT ACROSS THE REGION BY SUN/MON. EXPECT
BELOW NORMAL HIGHS ON SUNDAY ASSOC/W COLD ADVECTION IN THE WAKE OF
THE SAT NIGHT CLIPPER LOW...WITH A MODERATING TREND ON MON/MON
NIGHT. HOWEVER...A MORE ACTIVE/AMPLIFIED `EAST COAST TROUGH` TYPE
PATTERN APPEARS POISED TO DEVELOP AGAIN BY MID-WEEK...WHICH WILL
RESULT IN AN INCREASED CHANCE FOR CLOUD COVER AND PERHAPS
PRECIPITATION LATE TUE/EARLY WED AND BELOW NORMAL TEMPERATURES ON
WED/THU. GIVEN THAT PRECIPITATION CHANCES WILL HIGHLY DEPEND ON THE
EXACT TRACK/STRENGTH OF SHORTWAVE ENERGY ROTATING WITHIN A LARGER
SYNOPTIC SCALE TROUGH YET TO DEVELOP...AND THAT MODEL GUIDANCE HAS
HAD A RELATIVELY DIFFICULT TIME (W/REGARD TO QPF) IN THE SIMILAR
PATTERN IN PLACE THIS WEEK...UNCERTAINTY IS HIGHER THAN NORMAL FOR
120+ HRS OUT. GIVEN THE AFOREMENTIONED UNCERTAINTY AND THAT THE 12Z
GFS/ECMWF GENERATE LITTLE IF ANY PRECIP LATE TUE/EARLY WED...PREFER
TO KEEP A DRY FORECAST. -VINCENT
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS OF 1235 PM THURSDAY...
MVFR CONDITIONS FROM KRDU AND KFAY EASTWARD WILL GRADUALLY DIMINISH
THROUGH 22Z. VFR CONDITIONS OTHERWISE PERSIST THEN THROUGH THE 18Z
VALID TAF PERIOD. WINDS WILL LIGHTEN AND SLOWLY BACK...WITH A FEW
SOUTHWEST GUSTS IN THE TEENS TO AROUND 20KT DEVELOPING WITH MIXING
FRIDAY MORNING.
BEYOND THE 18Z VALID TAF PERIOD...MID-LEVEL CLOUDS WILL INCREASE
FRIDAY AFTERNOON INTO THE EVENING...AND THERE IS AN OUTSIDE CHANCE
OF A FLURRY OR SPRINKLE FRIDAY EVENING...BUT GUIDANCE CONSENSUS IS
FOR A HIGH PROBABILITY OF CONDITIONS REMAINING VFR WITH ANOTHER COLD
FRONT MOVING THROUGH LATE FRIDAY AND FRIDAY EVENING. BEHIND ANOTHER
COLD FRONT LATE IN THE WEEKEND...WEST-NORTHWEST WINDS COULD BE
BREEZY SUNDAY AND ESPECIALLY TOWARD KRWI WHERE THE GFS FORECAST THE
POTENTIAL FOR GUSTS WELL INTO THE 20S KTS. THE GFS MODEL ALSO
SUGGESTS THE POSSIBILITY OF MVFR CONDITIONS MAINLY TOWARD KFAY
MONDAY NIGHT...WITH OTHERWISE A HIGHEST PROBABILITY OF VFR
CONDITIONS IN CENTRAL NORTH CAROLINA.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DJF
NEAR TERM...HARTFIELD/DJF
SHORT TERM...VINCENT
LONG TERM...VINCENT
AVIATION...DJF
AREA FORECAST DISCUSSION
NWS RALEIGH NC
131 PM EST THU JAN 16 2014
.SYNOPSIS...HIGH PRESSURE BRIEFLY BUILDS OVER THE REGION TONIGHT...
BEFORE MOVING OFF THE COAST EARLY FRIDAY. ANOTHER COLD FRONT CROSSES
THE REGION FRIDAY AFTERNOON THROUGH FRIDAY NIGHT. HIGH PRESSURE
BRIEFLY BUILDS IN AGAIN FOR SATURDAY AHEAD OF YET ANOTHER COLD FRONT
THAT APPROACHES FROM THE WEST SATURDAY NIGHT.
&&
.NEAR TERM /TODAY THROUGH FRIDAY NIGHT/...
AS OF 940 AM THURSDAY...
A DRY AIR ON WATER VAPOR IMAGERY WAS MOVING IN FROM THE SOUTHWEST...
LINGERING PRECIPITATION MAINLY IN THE NORTHERN COASTAL PLAIN WAS
DIMINISHING ON RADAR AND MOVING OFF TO THE EAST AND NORTHEAST. THE
CLEARING LINE WAS ABOUT AS FAR EAST AS U.S. 1...AND THE CLEARING
COULD BE SLOW FOR THE NEXT FEW HOURS AS THE RAP SOUNDINGS AND ITS
LOW-LEVEL MOISTURE FORECAST...PLUS THE LOW CLOUD FORECAST FROM THE
HRRR WRF...INDICATE ONLY GRADUAL DRYING OF THE BOUNDARY LAYER FROM
WEST TO EAST. SKIES SHOULD BECOME PARTLY SUNNY IN THE U.S. 1
CORRIDOR FOR THE REST OF THE MORNING INTO THE EARLY AFTERNOON... BUT
IT MAY TAKE INTO MID-AFTERNOON OR SO IN MANY PART OF THE COASTAL
PLAIN...ESPECIALLY NORTH OF GOLDSBORO. LEFT MAXIMUM TEMPERATURES
ABOUT AS IS ON THE COOL SIDE OF GUIDANCE...WARMING A CATEGORY IN THE
TRIAD UNDER GOOD SUN AND WHERE KGSO HAS WARMED QUICKLY INTO THE
UPPER 30S. -DJF
THE SURFACE RIDGE CENTERED OVER THE CENTRAL GULF COAST AND NOSING
ACROSS NC LATER TODAY SLIPS QUICKLY TO OUR SE TONIGHT... AND EXPECT
FAIR SKIES WITH N WIND BACKING AROUND TO W AND SW OVERNIGHT....
LEADING TO STEADY OR SLIGHTLY RISING THICKNESSES LATE WITH THE ONSET
OF LOW LEVEL WARM AIR ADVECTION WITHIN THE RETURN FLOW. HAVE BUMPED
LOWS UP A DEGREE OR SO TO 27-30.
FOR FRI/FRI NIGHT: SOUTHWEST FLOW AHEAD OF THE NEXT CLIPPER COLD
FRONT SHOULD MAKE FOR A RATHER SEASONABLE DAY AS THICKNESSES WILL BE
CLOSE TO NORMALS. EXPECT PLENTY OF SUNSHINE WITH NO GOOD FEED OF
MOISTURE INTO THE AREA AT ANY LEVEL... ALTHOUGH A DECK OF MOSTLY MID
CLOUDS ASSOCIATED WITH THE APPROACHING MID LEVEL TROUGH AXIS IS
EXPECTED LATE FRI INTO FRI NIGHT GIVEN HEIGHT FALLS AROUND 100-120
M. OVERALL THE COLUMN SHOULD BE TOO DRY TO SUPPORT PRECIP DESPITE
THE HEIGHT FALLS AND MODEST UPPER DIVERGENCE AND DPVA. HIGHS AROUND
50 TO 55... A LITTLE ABOVE NORMAL. EXPECT TEMPS TO FALL BACK INTO
THE MID 20S FRI NIGHT WITH GOOD COLD AIR ADVECTION. -GIH
&&
.SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/...
AS OF 130 PM THURSDAY...
SATURDAY AND SATURDAY NIGHT: THE SYNOPTIC PATTERN WILL REMAIN ACTIVE
(ALBEIT DRY) IN ASSOC/W A PERSISTENT UPPER LEVEL TROUGH OVER THE
EASTERN CONUS. SENSIBLE WEATHER WILL BE DICTATED PRIMARILY BY A
`FINAL` ROUND OF SHORTWAVE ENERGY /DPVA/ AND AN ASSOCIATED CLIPPER-
TYPE SFC LOW APPROACHING THE REGION FROM THE NW ON SAT BEFORE
TRACKING EAST ACROSS THE MID-ATLANTIC SAT NIGHT. THE LATEST 12Z
MODEL GUIDANCE REMAINS DRY FOR CENTRAL NC...WHICH MAKES SENSE GIVEN
THE FAST MOVING NATURE OF THE SYSTEM (LITTLE CHANCE FOR MOISTURE
RECOVERY) AND THAT THE BEST DPVA /LAYER-LIFTING/ WILL OCCUR WELL TO
THE NORTH IN VICINITY OF THE MASON DIXON LINE. EXPECT BELOW NORMAL
HIGHS IN THE UPPER 30S TO LOWER 40S ON SATURDAY IN ASSOC/W COLD
ADVECTION IN THE WAKE OF A PRIOR SHORTWAVE/CLIPPER LOW AND ATTENDANT
DRY COLD FRONTAL PASSAGE FRI NIGHT. ONE WOULD THINK TEMPERATURES SAT
NIGHT WOULD HAVE A DIFFICULT TIME FALLING GIVEN A TIGHTENING MSLP
GRADIENT AND SOUTHERLY FLOW IN ADVANCE OF THE NEXT CLIPPER LOW
APPROACHING FROM THE NW...THOUGH EVEN SEVERAL HOURS OF RADIATIONAL
COOLING AFTER SUNSET COULD EASILY ALLOW TEMPS TO FALL INTO THE 20S
GIVEN THE AIRMASS IN PLACE. GIVEN THE TRACK OF THE SHORTWAVE AND
ASSOC CLIPPER LOW WILL BE WELL NORTH... ANTICIPATE THAT A RELATIVELY
TIGHT MSLP GRADIENT /SOUTHERLY FLOW/ WILL ONLY ALLOW FOR LOWS IN THE
UPPER 20S TO LOWER 30S...PERHAPS IN THE LOWER/MID 30S IF A SOUTHERLY
BREEZE IS PRESENT MOST OF THE EVENING/NIGHT. -VINCENT
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 310 AM WEDNESDAY
THE EXTENDED PERIOD WILL CONTINUE TO FEATURE AT LEAST A BROAD UPPER
TROUGH OVER THE EASTERN HALF OF THE US...WITH THE POTENTIAL FOR A
COUPLE MORE DISTURBANCES DIVING OUT OF CANADA AND HELPING TO AMPLIFY
THE TROUGH. HOWEVER...THE ECMWF AND GFS ARE NOT IN EVERY GOOD
AGREEMENT ON THE TIMING OR AMPLITUDE OF SUCH WAVES...AS THE ECMWF
SHOWS A RATHER PRONOUNCED WAVE ON MONDAY NIGHT AND THE GFS HAS WAVES
ON TUESDAY AFTERNOON AND WEDNESDAY NIGHT. THE PATTERN STILL FAVORS
MOSTLY DRY SYSTEMS WITH REINFORCING SHOTS OF COLD AIR AFTER A BRIEF
WARM UP ON MONDAY. WITHOUT BETTER MODEL AGREEMENT ITS DIFFICULT TO
ADD ANY MENTION OF PRECIP TO THE FORECAST. ABOVE NORMAL HIGHS IN
THE MID AND UPPER 50S ON MONDAY WILL TREND DOWNWARD INTO THE 40S BY
THE MIDDLE OF NEXT WEEK.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS OF 1235 PM THURSDAY...
MVFR CONDITIONS FROM KRDU AND KFAY EASTWARD WILL GRADUALLY DIMINISH
THROUGH 22Z. VFR CONDITIONS OTHERWISE PERSIST THEN THROUGH THE 18Z
VALID TAF PERIOD. WINDS WILL LIGHTEN AND SLOWLY BACK...WITH A FEW
SOUTHWEST GUSTS IN THE TEENS TO AROUND 20KT DEVELOPING WITH MIXING
FRIDAY MORNING.
BEYOND THE 18Z VALID TAF PERIOD...MID-LEVEL CLOUDS WILL INCREASE
FRIDAY AFTERNOON INTO THE EVENING...AND THERE IS AN OUTSIDE CHANCE
OF A FLURRY OR SPRINKLE FRIDAY EVENING...BUT GUIDANCE CONSENSUS IS
FOR A HIGH PROBABILITY OF CONDITIONS REMAINING VFR WITH ANOTHER COLD
FRONT MOVING THROUGH LATE FRIDAY AND FRIDAY EVENING. BEHIND ANOTHER
COLD FRONT LATE IN THE WEEKEND...WEST-NORTHWEST WINDS COULD BE
BREEZY SUNDAY AND ESPECIALLY TOWARD KRWI WHERE THE GFS FORECAST THE
POTENTIAL FOR GUSTS WELL INTO THE 20S KTS. THE GFS MODEL ALSO
SUGGESTS THE POSSIBILITY OF MVFR CONDITIONS MAINLY TOWARD KFAY
MONDAY NIGHT...WITH OTHERWISE A HIGHEST PROBABILITY OF VFR
CONDITIONS IN CENTRAL NORTH CAROLINA.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DJF
NEAR TERM...HARTFIELD/DJF
SHORT TERM...VINCENT
LONG TERM...SMITH
AVIATION...DJF
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1235 PM EST THU JAN 16 2014
.SYNOPSIS...HIGH PRESSURE BRIEFLY BUILDS OVER THE REGION TONIGHT...
BEFORE MOVING OFF THE COAST EARLY FRIDAY. ANOTHER COLD FRONT CROSSES
THE REGION FRIDAY AFTERNOON THROUGH FRIDAY NIGHT. HIGH PRESSURE
BRIEFLY BUILDS IN AGAIN FOR SATURDAY AHEAD OF YET ANOTHER COLD FRONT
THAT APPROACHES FROM THE WEST SATURDAY NIGHT.
&&
.NEAR TERM /TODAY THROUGH FRIDAY NIGHT/...
AS OF 940 AM THURSDAY...
A DRY AIR ON WATER VAPOR IMAGERY WAS MOVING IN FROM THE SOUTHWEST...
LINGERING PRECIPITATION MAINLY IN THE NORTHERN COASTAL PLAIN WAS
DIMINISHING ON RADAR AND MOVING OFF TO THE EAST AND NORTHEAST. THE
CLEARING LINE WAS ABOUT AS FAR EAST AS U.S. 1...AND THE CLEARING
COULD BE SLOW FOR THE NEXT FEW HOURS AS THE RAP SOUNDINGS AND ITS
LOW-LEVEL MOISTURE FORECAST...PLUS THE LOW CLOUD FORECAST FROM THE
HRRR WRF...INDICATE ONLY GRADUAL DRYING OF THE BOUNDARY LAYER FROM
WEST TO EAST. SKIES SHOULD BECOME PARTLY SUNNY IN THE U.S. 1
CORRIDOR FOR THE REST OF THE MORNING INTO THE EARLY AFTERNOON... BUT
IT MAY TAKE INTO MID-AFTERNOON OR SO IN MANY PART OF THE COASTAL
PLAIN...ESPECIALLY NORTH OF GOLDSBORO. LEFT MAXIMUM TEMPERATURES
ABOUT AS IS ON THE COOL SIDE OF GUIDANCE...WARMING A CATEGORY IN THE
TRIAD UNDER GOOD SUN AND WHERE KGSO HAS WARMED QUICKLY INTO THE
UPPER 30S. -DJF
THE SURFACE RIDGE CENTERED OVER THE CENTRAL GULF COAST AND NOSING
ACROSS NC LATER TODAY SLIPS QUICKLY TO OUR SE TONIGHT... AND EXPECT
FAIR SKIES WITH N WIND BACKING AROUND TO W AND SW OVERNIGHT....
LEADING TO STEADY OR SLIGHTLY RISING THICKNESSES LATE WITH THE ONSET
OF LOW LEVEL WARM AIR ADVECTION WITHIN THE RETURN FLOW. HAVE BUMPED
LOWS UP A DEGREE OR SO TO 27-30.
FOR FRI/FRI NIGHT: SOUTHWEST FLOW AHEAD OF THE NEXT CLIPPER COLD
FRONT SHOULD MAKE FOR A RATHER SEASONABLE DAY AS THICKNESSES WILL BE
CLOSE TO NORMALS. EXPECT PLENTY OF SUNSHINE WITH NO GOOD FEED OF
MOISTURE INTO THE AREA AT ANY LEVEL... ALTHOUGH A DECK OF MOSTLY MID
CLOUDS ASSOCIATED WITH THE APPROACHING MID LEVEL TROUGH AXIS IS
EXPECTED LATE FRI INTO FRI NIGHT GIVEN HEIGHT FALLS AROUND 100-120
M. OVERALL THE COLUMN SHOULD BE TOO DRY TO SUPPORT PRECIP DESPITE
THE HEIGHT FALLS AND MODEST UPPER DIVERGENCE AND DPVA. HIGHS AROUND
50 TO 55... A LITTLE ABOVE NORMAL. EXPECT TEMPS TO FALL BACK INTO
THE MID 20S FRI NIGHT WITH GOOD COLD AIR ADVECTION. -GIH
&&
.SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/...
AS OF 310 AM THURSDAY...
AFTER THE PASSAGE OF A DRY CLIPPER AND COLD FRONT FRIDAY
NIGHT...THICKNESS START OUR AROUND 1270M SATURDAY MORNING. WINDS
WILL TURN TO SOUTHWESTERLY DURING THE AFTERNOON IN RESPONSE TO A
SECOND SHORTWAVE APPROACHING FROM THE NORTHWEST...BUT NOT IN TIME TO
MODERATE TEMPS VERY MUCH...WITH STATISTICAL GUIDANCE AND DRY
ADIABATIC MIXING TO AROUND 900MB GIVING UPPER 30S TO MID 40S.
THE AFOREMENTIONED SECOND CLIPPER WILL CROSS THE CENTRAL
APPALACHIANS SATURDAY NIGHT. WHILE MODELS SHOW A LITTLE MORE
MOISTURE ACCOMPANYING THIS WAVE...THE MOISTURE RETURNS IS BRIEF/WEAK
AND MOST LY CONFINED TO THE MID-LEVELS AFTER CROSSING THE MOUNTAINS.
WILL KEEP THE FORECAST DRY BASED ON THIS AND THE PREVIOUSLY
DISCUSSED DRYING TREND IN MODEL RUNS. LOWS 26-30.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 310 AM WEDNESDAY
THE EXTENDED PERIOD WILL CONTINUE TO FEATURE AT LEAST A BROAD UPPER
TROUGH OVER THE EASTERN HALF OF THE US...WITH THE POTENTIAL FOR A
COUPLE MORE DISTURBANCES DIVING OUT OF CANADA AND HELPING TO AMPLIFY
THE TROUGH. HOWEVER...THE ECMWF AND GFS ARE NOT IN EVERY GOOD
AGREEMENT ON THE TIMING OR AMPLITUDE OF SUCH WAVES...AS THE ECMWF
SHOWS A RATHER PRONOUNCED WAVE ON MONDAY NIGHT AND THE GFS HAS WAVES
ON TUESDAY AFTERNOON AND WEDNESDAY NIGHT. THE PATTERN STILL FAVORS
MOSTLY DRY SYSTEMS WITH REINFORCING SHOTS OF COLD AIR AFTER A BRIEF
WARM UP ON MONDAY. WITHOUT BETTER MODEL AGREEMENT ITS DIFFICULT TO
ADD ANY MENTION OF PRECIP TO THE FORECAST. ABOVE NORMAL HIGHS IN
THE MID AND UPPER 50S ON MONDAY WILL TREND DOWNWARD INTO THE 40S BY
THE MIDDLE OF NEXT WEEK.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS OF 1235 PM THURSDAY...
MVFR CONDITIONS FROM KRDU AND KFAY EASTWARD WILL GRADUALLY DIMINISH
THROUGH 22Z. VFR CONDITIONS OTHERWISE PERSIST THEN THROUGH THE 18Z
VALID TAF PERIOD. WINDS WILL LIGHTEN AND SLOWLY BACK...WITH A FEW
SOUTHWEST GUSTS IN THE TEENS TO AROUND 20KT DEVELOPING WITH MIXING
FRIDAY MORNING.
BEYOND THE 18Z VALID TAF PERIOD...MID-LEVEL CLOUDS WILL INCREASE
FRIDAY AFTERNOON INTO THE EVENING...AND THERE IS AN OUTSIDE CHANCE
OF A FLURRY OR SPRINKLE FRIDAY EVENING...BUT GUIDANCE CONSENSUS IS
FOR A HIGH PROBABILITY OF CONDITIONS REMAINING VFR WITH ANOTHER COLD
FRONT MOVING THROUGH LATE FRIDAY AND FRIDAY EVENING. BEHIND ANOTHER
COLD FRONT LATE IN THE WEEKEND...WEST-NORTHWEST WINDS COULD BE
BREEZY SUNDAY AND ESPECIALLY TOWARD KRWI WHERE THE GFS FORECAST THE
POTENTIAL FOR GUSTS WELL INTO THE 20S KTS. THE GFS MODEL ALSO
SUGGESTS THE POSSIBILITY OF MVFR CONDITIONS MAINLY TOWARD KFAY
MONDAY NIGHT...WITH OTHERWISE A HIGHEST PROBABILITY OF VFR
CONDITIONS IN CENTRAL NORTH CAROLINA.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DJF
NEAR TERM...HARTFIELD/DJF
SHORT TERM...SMITH
LONG TERM...SMITH
AVIATION...DJF
AREA FORECAST DISCUSSION
NWS RALEIGH NC
940 AM EST THU JAN 16 2014
.SYNOPSIS...BEHIND A COLD FRONT MOVING OFF THE NORTH CAROLINA
COAST...HIGH PRESSURE BUILDS BRIEFLY INTO THE AREA FROM THE WEST
LATER TODAY THROUGH TONIGHT...BEFORE MOVING OFF THE SOUTHEAST COAST
EARLY FRIDAY. ANOTHER MAINLY DRY COLD FRONT CROSSES THE REGION
FRIDAY EVENING.
&&
.NEAR TERM /TODAY THROUGH FRIDAY NIGHT/...
AS OF 940 AM THURSDAY...
A DRY AIR ON WATER VAPOR IMAGERY WAS MOVING IN FROM THE SOUTHWEST...
LINGERING PRECIPITATION MAINLY IN THE NORTHERN COASTAL PLAIN WAS
DIMINISHING ON RADAR AND MOVING OFF TO THE EAST AND NORTHEAST. THE
CLEARING LINE WAS ABOUT AS FAR EAST AS U.S. 1...AND THE CLEARING
COULD BE SLOW FOR THE NEXT FEW HOURS AS THE RAP SOUNDINGS AND ITS
LOW-LEVEL MOISTURE FORECAST...PLUS THE LOW CLOUD FORECAST FROM THE
HRRR WRF...INDICATE ONLY GRADUAL DRYING OF THE BOUNDARY LAYER FROM
WEST TO EAST. SKIES SHOULD BECOME PARTLY SUNNY IN THE U.S. 1
CORRIDOR FOR THE REST OF THE MORNING INTO THE EARLY AFTERNOON... BUT
IT MAY TAKE INTO MID-AFTERNOON OR SO IN MANY PART OF THE COASTAL
PLAIN...ESPECIALLY NORTH OF GOLDSBORO. LEFT MAXIMUM TEMPERATURES
ABOUT AS IS ON THE COOL SIDE OF GUIDANCE...WARMING A CATEGORY IN THE
TRIAD UNDER GOOD SUN AND WHERE KGSO HAS WARMED QUICKLY INTO THE
UPPER 30S. -DJF
THE SURFACE RIDGE CENTERED OVER THE CENTRAL GULF COAST AND NOSING
ACROSS NC LATER TODAY SLIPS QUICKLY TO OUR SE TONIGHT... AND EXPECT
FAIR SKIES WITH N WIND BACKING AROUND TO W AND SW OVERNIGHT....
LEADING TO STEADY OR SLIGHTLY RISING THICKNESSES LATE WITH THE ONSET
OF LOW LEVEL WARM AIR ADVECTION WITHIN THE RETURN FLOW. HAVE BUMPED
LOWS UP A DEGREE OR SO TO 27-30.
FOR FRI/FRI NIGHT: SOUTHWEST FLOW AHEAD OF THE NEXT CLIPPER COLD
FRONT SHOULD MAKE FOR A RATHER SEASONABLE DAY AS THICKNESSES WILL BE
CLOSE TO NORMALS. EXPECT PLENTY OF SUNSHINE WITH NO GOOD FEED OF
MOISTURE INTO THE AREA AT ANY LEVEL... ALTHOUGH A DECK OF MOSTLY MID
CLOUDS ASSOCIATED WITH THE APPROACHING MID LEVEL TROUGH AXIS IS
EXPECTED LATE FRI INTO FRI NIGHT GIVEN HEIGHT FALLS AROUND 100-120
M. OVERALL THE COLUMN SHOULD BE TOO DRY TO SUPPORT PRECIP DESPITE
THE HEIGHT FALLS AND MODEST UPPER DIVERGENCE AND DPVA. HIGHS AROUND
50 TO 55... A LITTLE ABOVE NORMAL. EXPECT TEMPS TO FALL BACK INTO
THE MID 20S FRI NIGHT WITH GOOD COLD AIR ADVECTION. -GIH
&&
.SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/...
AS OF 310 AM THURSDAY...
AFTER THE PASSAGE OF A DRY CLIPPER AND COLD FRONT FRIDAY
NIGHT...THICKNESS START OUR AROUND 1270M SATURDAY MORNING. WINDS
WILL TURN TO SOUTHWESTERLY DURING THE AFTERNOON IN RESPONSE TO A
SECOND SHORTWAVE APPROACHING FROM THE NORTHWEST...BUT NOT IN TIME TO
MODERATE TEMPS VERY MUCH...WITH STATISTICAL GUIDANCE AND DRY
ADIABATIC MIXING TO AROUND 900MB GIVING UPPER 30S TO MID 40S.
THE AFOREMENTIONED SECOND CLIPPER WILL CROSS THE CENTRAL
APPALACHIANS SATURDAY NIGHT. WHILE MODELS SHOW A LITTLE MORE
MOISTURE ACCOMPANYING THIS WAVE...THE MOISTURE RETURNS IS BRIEF/WEAK
AND MOST LY CONFINED TO THE MID-LEVELS AFTER CROSSING THE MOUNTAINS.
WILL KEEP THE FORECAST DRY BASED ON THIS AND THE PREVIOUSLY
DISCUSSED DRYING TREND IN MODEL RUNS. LOWS 26-30.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 310 AM WEDNESDAY
THE EXTENDED PERIOD WILL CONTINUE TO FEATURE AT LEAST A BROAD UPPER
TROUGH OVER THE EASTERN HALF OF THE US...WITH THE POTENTIAL FOR A
COUPLE MORE DISTURBANCES DIVING OUT OF CANADA AND HELPING TO AMPLIFY
THE TROUGH. HOWEVER...THE ECMWF AND GFS ARE NOT IN EVERY GOOD
AGREEMENT ON THE TIMING OR AMPLITUDE OF SUCH WAVES...AS THE ECMWF
SHOWS A RATHER PRONOUNCED WAVE ON MONDAY NIGHT AND THE GFS HAS WAVES
ON TUESDAY AFTERNOON AND WEDNESDAY NIGHT. THE PATTERN STILL FAVORS
MOSTLY DRY SYSTEMS WITH REINFORCING SHOTS OF COLD AIR AFTER A BRIEF
WARM UP ON MONDAY. WITHOUT BETTER MODEL AGREEMENT ITS DIFFICULT TO
ADD ANY MENTION OF PRECIP TO THE FORECAST. ABOVE NORMAL HIGHS IN
THE MID AND UPPER 50S ON MONDAY WILL TREND DOWNWARD INTO THE 40S BY
THE MIDDLE OF NEXT WEEK.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
AS OF 645 AM THURSDAY...
VFR CONDITIONS ARE LIKELY TO PERSIST THROUGH 12Z FRI AT INT/GSO.
HOWEVER... AT RDU/FAY AND ESPECIALLY RWI... MVFR TO IFR CONDITIONS
ARE LIKELY TO HOLD UNTIL AROUND 16Z-19Z THIS MORNING. A COLD FRONT
CURRENTLY MOVING THROUGH THE AREA WILL SLIP TO COASTAL NC THIS
MORNING... BRINGING DRIER AIR IN SLOWLY FROM WEST TO EAST. THE
FRONTAL ZONE ALOFT WILL DRIFT VERY SLOWLY OVER CENTRAL NC TODAY...
KEEPING PLENTY OF MOISTURE BETWEEN 1500 AGL AND 6000 AGL. A BRIEF
PERIOD OF LIGHT MIXED RAIN OR LIGHT SNOW REMAINS POSSIBLE AT RDU/RWI
BEFORE 14Z... BUT VSBYS SHOULD REMAIN VFR. CIGS ARE EXPECTED TO
IMPROVE TO VFR THEN UNLIMITED SKIES AT RDU/FAY BY 19Z ... AND AT RWI
BY 21Z AS THE FRONT ALOFT MOVES EASTWARD. VFR CONDITIONS WILL THEN
DOMINATE AT ALL SITES FROM SUNSET THROUGH 12Z FRI MORNING AS HIGH
PRESSURE RIDGING MOVES INTO THE AREA.
LOOKING BEYOND 12Z FRI... VFR CONDITIONS WILL DOMINATE THROUGH
MONDAY. A SERIES OF DRY COLD FRONTS WILL PASS THROUGH CENTRAL NC...
FIRST FRI EVENING AND AGAIN LATE SAT NIGHT. BETWEEN THESE TIMES...
HIGH PRESSURE RIDGING WILL STRETCH ACROSS THE AREA. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HARTFIELD/DJF
NEAR TERM...HARTFIELD/DJF
SHORT TERM...SMITH
LONG TERM...SMITH
AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1216 AM CST THU JAN 16 2014
.UPDATE...
ISSUED AT 1215 AM CST THU JAN 16 2014
LATEST SURFACE ANALYSIS SHOWS THE STRONGEST PRESSURE RISES OF
8MB/3HRS IN SOUTHERN MANITOBA. THE RUC13 BRINGS THIS DOWN IN
CHUNKS OVERNIGHT THROUGH THURSDAY MORNING. THAT WILL RESULT IN A
PROLONG PERIOD OF VERY STRONG WINDS PER CURRENT/PREVIOUS
FORECASTS. STRONGEST WIND GUST THUS FAR OCCURRED AT 1155 PM CST
WEDNESDAY WITH 71 MPH AT MINOT AIR FORCE BASE. VISIBILITIES OF
AROUND ONE QUARTER MILE IN SNOW SHOWERS OVERNIGHT WILL CONTINUE
ESPECIALLY FROM THE TURTLE MOUNTAINS INTO THE JAMES RIVER VALLEY.
NO MAJOR UPDATES FROM PREVIOUS DISCUSSIONS/FORECASTS.
UPDATE ISSUED AT 948 PM CST WED JAN 15 2014
THE MINOT RADAR INDICATES SNOW SHOWERS DIVING SOUTH ACROSS NORTH
CENTRAL NORTH DAKOTA THIS EVENING. HOWEVER...SURFACE OBS ARE
REPORTING ISOLATED SNOW SHOWERS AT BEST. AS A RESULT...ADDED
ISOLATED SNOW SHOWERS NORTH CENTRAL FOR THIS EVENING BASED ON THE
SURFACE OBS.
OTHERWISE...WINDS CONTINUE TO INCREASE TONIGHT IN RESPONSE TO DEEP
LOW PRESSURE DIVING SOUTHEAST ACROSS SOUTHERN MANITOBA. THE
HIGHEST WINDS CONTINUE TO BE ACROSS NORTHERN NORTH DAKOTA...BUT
ARE SLOWLY MAKING THEIR WAY SOUTHWARD. THE CURRENT WIND AND
BLIZZARD HEADLINES CONTINUE TO BE ON TRACK WITH NO UPDATES
REQUIRED.
UPDATE ISSUED AT 703 PM CST WED JAN 15 2014
NO MAJOR UPDATES WERE REQUIRED TO THE ONGOING FORECAST. ROLLA HAS
ALREADY GUSTED TO 62 MPH AND THE OB AT CROSBY HAD SUSTAINED WINDS
AT 40 MPH WITHIN THE LAST HOUR. THE HIGHER WINDS WILL SLOWLY MOVE
SOUTHWARD TONIGHT AS A DEEP SURFACE LOW PRESSURE SLIDES SOUTH INTO
NORTHERN MINNESOTA OVERNIGHT. THE CURRENT HEADLINES ARE IN GOOD
SHAPE. ONLY ISSUED AN UPDATE TO THE NPW TO FRESHEN UP THE EVENING
WORDING.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 345 PM CST WED JAN 15 2014
MAIN ISSUE THIS FORECAST IS THE STRONG WINDS AND POTENTIAL FOR
BLOWING SNOW. BASED ON MANY HOURS OF SURFACE OBS ACROSS CANADA SO
FAR TODAY...WITH TEMPERATURES IN THE LOWER 40S...AND WINDS
GUSTING TO 60 MPH ACROSS SASKATCHEWAN AND WESTERN MANITOBA...
BELIEVE THE POTENTIAL FOR BLOWING SNOW IS LOW ACROSS WEST AND CENTRAL
NORTH DAKOTA. HIGH TEMPERATURES HAVE WARMED INTO THE LOWER 40S
OVER MOST IF THE AREA. AS A RESULT A HIGH WIND WARNING CONTINUES
FOR WEST AND CENTRAL NORTH DAKOTA WEST OF THE JAMES RIVER VALLEY.
IN THE JAMES RIVER VALLEY FROM CARRINGTON SOUTH TO ELLENDALE...THE
POTENTIAL FOR BLOWING SNOW IS GREATER AS THE SNOW COVER IS LESS
CRUSTED. GFS-NAM MODELS FORECAST A H850 WIND FIELD OF 65 TO 75 KTS
ACROSS WEST AND CENTRAL NORTH DAKOTA TONIGHT INTO THURSDAY.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 345 PM CST WED JAN 15 2014
THE HIGHLIGHT OF THE EXTENDED FORECAST IS THE POTENTIAL FOR STRONG
WINDS FRIDAY EVENING INTO SATURDAY MORNING.
THE 12 UTC DETERMINISTIC SUITE IS IN AGREEMENT ON ANOTHER CLIPPER
PROPAGATING ACROSS WINNIPEG FRIDAY EVENING AND INTO MINNESOTA BY
SATURDAY MORNING. THIS WOULD SUGGEST THE POTENTIAL FOR ANOTHER
ROUND OF STRONG WINDS IN THE WAKE OF ITS ASSOCIATED OCCLUDING
FRONT FRIDAY EVENING INTO SATURDAY MORNING. 0.5 KM WINDS OF 45-50
KTS ARE FORECAST WITH ISALLOBARIC FORCING VIA A 10-12MB/6 HR
PRESSURE RISE BUBBLE. AT THIS TIME IS APPEARS BORDERLINE FOR HIGH
WIND WARNING CRITERIA...HOWEVER...A WIND ADVISORY MAY BE NEEDED.
THEREAFTER...THE PATTERN REMAINS THE SAME ON NEAR TO SLIGHTLY
ABOVE AVERAGE TEMPERATURES AND A FAVORABLE SETUP FOR CLIPPERS
DOWNSTREAM OF THE WESTERN CONUS UPPER LEVEL RIDGE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1215 AM CST THU JAN 16 2014
VERY STRONG NORTHWEST WINDS BETWEEN 40KT AND 50KT WILL CONTINUE
ACROSS THE AERODROMES THROUGH THURSDAY MORNING. BLIZZARD CONDITIONS
WITH VISIBILITIES OF LIFR TO VLIFR AT KJMS WITH CIGS RANGING
BETWEEN IFR AND MVFR. ELSEWHERE GUSTY WINDS WITH MVFR CIGS TO LOW
VFR CIGS. WINDS WILL BEGIN TO TAPER THURSDAY AFTERNOON THROUGH THE
EVENING.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WARNING UNTIL 6 PM CST /5 PM MST/ THIS EVENING FOR
NDZ001>005-009>013-017>023-031>036-040>047-050.
BLIZZARD WARNING UNTIL 6 PM CST THIS EVENING FOR NDZ025-037-048-
051.
&&
$$
UPDATE...KS
SHORT TERM...WAA
LONG TERM...AYD
AVIATION...KS
AREA FORECAST DISCUSSION
NWS PORTLAND OR
228 PM PST THU JAN 16 2014
.SYNOPSIS...HIGH PRESSURE WILL REMAIN OVER THE REGION THROUGH
SATURDAY MORNING...ALLOWING VALLEY FOG AND LOW CLOUDS TO PERSIST
WHILE MILD AND SUNNY CONDITIONS WILL DOMINATE THE WEATHER FOR COASTAL
AND MOUNTAIN LOCATIONS. A WEAK FRONT ARRIVING LATE SATURDAY INTO
SUNDAY WILL BRING A SMALL CHANCE FOR LIGHT RAIN TO THE COAST.
OTHERWISE...HIGH PRESSURE IS EXPECTED TO DOMINATE THE WEATHER AGAIN
NEXT WEEK AND BRING MORE OF SAME WEATHER OF LATE.
&&
.SHORT TERM...A SUBSTANTIAL SUBSIDENCE INVERSION LIES BETWEEN 1000
AND 3000 FEET TODAY...RESULTING IN TEMPERATURES WARMING AT LEAST 20
DEGREES AS ONE GOES UP BETWEEN THESE TWO ELEVATIONS. WHILE RAWS
STATIONS HAVE A WARM BIAS ON LOW WIND...SUNNY DAYS...60S CERTAINLY
ABOUND ACROSS MOST OF THE HIGHER HILLS IN THE COAST RANGE AND
CASCADE FOOTHILLS.
VISIBLE SATELLITE IMAGERY INDICATES LOW CLOUDS ARE HANGING TOUGH
ACROSS THE SOUTHERN HALF OF THE WILLAMETTE VALLEY...NORTH OF I84 IN
THE PORTLAND METRO AREA AND ALONG THE KELSO TO CASTLE ROCK CORRIDOR
THIS AFTERNOON. IT IS CERTAINLY INTERESTING THAT MCMINNVILLE AND
HILLSBORO CLEARED BEFORE KTTD AND KPDX. THE HRRR INDICATES LOW LEVEL
WINDS WILL REMAIN NORTHWESTERLY ALONG THE COLUMBIA RIVER NEAR KPDX
AND KTTD UNTIL LATE TONIGHT SO THESE AREAS WILL BE HARD PRESSED TO
GO COMPLETELY CLEAR THIS AFTERNOON BASED ON VISIBLE SATELLITE
TRENDS. WHAT CLEARING DOES OCCUR SHOULD BE SHORT LIVED AS CLOUDS AND
FOG FILL BACK IN QUICKLY THIS EVENING.
THE CURRENT KDLS-KTTD PRESSURE GRADIENT IS HOVERING NEAR 4MB AND
SHOULD RAMP UP LATER TONIGHT TO APPROXIMATELY 6MB...PERHAPS 7MB.
BECAUSE THE KDLS-KTTD PRESSURE GRADIENT SHOULD ONLY BE STRONGER
FRIDAY MANY OF THE SAME AREAS WILL CLEAR FRIDAY AFTERNOON...PLUS
THOSE THAT WERE OH SO CLOSE TODAY INCLUDING CLARK COUNTY AND PERHAPS
SALEM. EXPECT TEMPERATURES TO BE SIMILAR FRIDAY...BUT A TOUCH COOLER
NEAR THE CENTRAL OREGON COAST WHERE LOW LEVEL WINDS WILL TURN A
LITTLE MORE SOUTHERLY.
OTHERWISE...A SHORTWAVE TROUGH STILL LOOKS ON TRACK TO SLIDE EASTWARD
WELL NORTH OF OUR CWA LATE SATURDAY. THIS WILL DRAG A DYING FRONT
INTO OUR COASTAL WATERS WITH A SLIGHT CHANCE THAT MEASURABLE RAIN
WILL OCCUR ALONG THE NORTHWEST OREGON COAST AND FAR SOUTHWEST
WASHINGTON. HOWEVER...DPROG/DT CONTINUES TO SUGGEST THIS IS LESS AND
LESS LIKELY. RIDGING WILL THEN BEGIN TO BUILD NORTHWARD ACROSS THE
NORTHEAST PACIFIC ON SUNDAY. THE REMNANTS OF THE AFOREMENTIONED
FRONT WILL LIFT NORTHWARD AND ACT AS A WARM FRONT...BRINGING ANOTHER
SMALL CHANCE FOR LIGHT PRECIPITATION SUNDAY...BUT AGAIN MODELS SEEM
TO BE TRENDING DRIER WITH THIS SYSTEM SO POPS WERE KEPT GENERALLY
SLIGHT CHANCE OR LESS. /NEUMAN
.LONG TERM...SUNDAY NIGHT THROUGH THURSDAY. FEW CHANGES IN THE
EXTENDED PERIOD. AFTER THE WEAK FRONT PASSES THROUGH THE AREA ON
SUNDAY...HIGH PRESSURE WILL QUICKLY REBUILD OVER THE EASTERN PACIFIC
AND PACIFIC NORTHWEST. THIS RIDGE WILL CONTINUE TO DOMINATE OUR
WEATHER PATTERN AND BY TUESDAY THE UPPER RIDGE WILL AMPLIFY WITH THE
RIDGE AXIS LOCATED ALONG OR NEAR THE WEST COAST. BOTH THE 12Z ECMWF
AND GFS DEPICT A SHORTWAVE IMPULSE THAT SPLITS NEAR 140W EARLY NEXT
WEEK...WITH A CLOSED LOW MOVING INTO THE CENTRAL CA COAST AND AN
UPPER LEVEL TROUGH WELL TO OUR NORTH OVER THE TOP OF THE RIDGE.
UNTIL THE FORECAST MODELS GIVE A STRONG REASON TO BELIEVE
OTHERWISE...IT APPEARS THIS RIDGE WILL CONTINUE REMAIN IN PLACE AND
KEEP THE FORECAST AREA DRY THROUGH AT LEAST LATE NEXT WEEK.
A RETURN OF DAILY FOG AND LOW CLOUDS IS LIKELY FOR THE VALLEY
LOCATIONS...THOUGH THE NORTH WILLAMETTE VALLEY MAY BE MORE LIKELY TO
SEE LESS FOG AND/OR BREAK OUT EARLIER DURING THE MIDDLE OF NEXT WEEK
DEPENDING ON EAST WINDS DEVELOPING THROUGH THE COLUMBIA RIVER GORGE.
HIGH TEMPERATURES LOOK TO BE A FEW DEGREES ABOVE SEASONAL NORMALS
THROUGH THE EXTENDED WHILE LOWS WILL BE NEAR NORMS. CULLEN
&&
.AVIATION...COMPLICATED EVOLUTION TO CLEARING THIS AFTERNOON. THE
COLD LOW LEVEL AIR HAS KEPT AN ONSHORE GRADIENT DOWN THE COLUMBIA
RIVER AND THE PORTLAND TO TROUTDALE GRADIENT IS STILL 0.7 MB.
MEANWHILE OFFSHORE FLOW ALOFT IS ERODING CLOUDS FROM THE TOP
DOWN. CLOUDS WILL REMAIN MOST PERSISTENT FROM SALEM SOUTH...AND
ALONG THE COLUMBIA RIVER FROM SCAPPOOSE TO NEAR PORTLAND. STILL
DO EXPECT SOME CLEARING AT KTTD AND KPDX AND AT HIO. CHANCES ARE
THAT KSLE SEES A BRIEF BREAK THIS AFTERNOON. EXPECT THAT WE RETURN
TO IFR CONDITIONS AGAIN WITH FOG OR LOW CLOUDS DEPENDING ON IF
CLEARING HAS OCCURRED...AND LIKELY VERY QUICKLY. AT LEAST
PERSISTENCE RULES AT KEUG.
ALSO COMPLICATED WIND FORECAST AS THE HRRR KEEPS THE ONSHORE
GRADIENT IN PLACE FROM KPDX-KTTD AND KEEPS THE EAST WIND CONFINED
TO THE GORGE THROUGH A LITTLE AFTER MIDNIGHT...WHILE MOS GUIDANCE
AND HI RESOLUTION NAM SPREADS IT IN MUCH SOONER. EXPECT THAT IT
WILL EVENTUALLY GET IN AS THE OFFSHORE GRADIENT GETS A BIT
STRONGER LATER TONIGHT. EXPECT THIS TO ALLOW NORTH VALLEY CLEARING
AND POSSIBLY A BIT MORE ON FRIDAY. KMD
KPDX AND APPROACHES...BRIEF PERIOD OF CLEARING WILL BE FOLLOWED
BY A RETURN TO LIFR FOG AND OR LOW CLOUDS THIS EVENING AND
OVERNIGHT. AS WE APPROACH MORNING...THE OFFSHORE GRADIENT WILL
BEGIN WORKING ITS WAY IN THE EAST OPERATIONS AREA WHICH SHOULD
HELP TO ERODE CLOUDS OR AT LEAST LIFT CLOUDS AND VSBYS WITH GOOD
CLEARING FOR TOMORROW AFTERNOON. KMD
&&
.MARINE...HIGH PRES REMAINS OVER THE PAC NW THROUGH THE WEEKEND.
THIS WILL MAINTAIN WEAK PRES GRADIENTS AND E WINDS 15 KT OR
LESS...THOUGH EXPECT SOME GUSTS TO 20 KT FROM TIME TO
TIME...MAINLY ON FRI. SEAS CONTINUE TO SUBSIDE.
A WEAK FRONT WILL PUSH ACROSS REGION THIS WEEKEND...BUT NOT MUCH
IN WAY OF WIND. WILL SEE SEVERAL SWELL TRAINS OF 10 TO 12 FT
ARRIVING THIS WEEKEND INTO EARLY NEXT WEEK. ROCKEY.
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...AIR STAGNATION ADVISORY UNTIL 10 AM PST TUESDAY FOR CENTRAL
WILLAMETTE VALLEY-SOUTH WILLAMETTE VALLEY.
WA...NONE.
PZ...NONE.
&&
$$
MORE WEATHER INFORMATION ONLINE AT..
HTTP://WEATHER.GOV/PORTLAND
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.PORTLAND.GOV
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...UPDATED
NWS MEMPHIS TN
1117 AM CST THU JAN 16 2014
.UPDATE...
UPDATED TO INCLUDE THE 18Z AVIATION DISCUSSION BELOW.
JCL
&&
.DISCUSSION... /ISSUED 955 AM CST THU JAN 16 2014/
SKIES ARE PARTLY CLOUDY ACROSS MUCH OF THE FORECAST AREA THIS
MORNING WITH TEMPERATURES RANGING FROM THE UPPER 20S TO LOWER 40S.
SOME SNOW FLURRIES HAVE BEEN MOVING ACROSS NORTHERN SECTIONS OF
THE FORECAST AREA BUT IT APPEARS THAT LITTLE OF THE ACTIVITY IS
REACHING THE GROUND. AS TEMPERATURES WARM THE THREAT OF SNOW
FLURRIES WILL DIMINISH. WILL UPDATE FORECAST TO REMOVE MORNING
WORDING BUT NO BIG CHANGES ARE NEEDED AT THIS TIME.
ARS
PREV DISCUSSION... /ISSUED 534 AM CST THU JAN 16 2014/
SHORT TERM...TODAY THROUGH SUNDAY... SLOW WAA HAS BEGUN TO TAKE
PLACE OVERNIGHT AS WINDS HAVE SHIFTED SOUTHERLY. TEMPERATURES
ACROSS THE MID-SOUTH ARE NEAR 30 IN THE WESTERN PART OF THE
FORECAST AREA...WITH 20S TO THE EAST WHERE WINDS HAVEN`T QUITE
PICKED UP YET. TO THE NORTH OF OUR AREA LIGHT SNOW HAS DEVELOPED
NEAR THE ST LOUIS METRO AREA. RADAR TRENDS AND LATEST HRRR MODEL
GUIDANCE SUGGESTS THAT LIGHT FLURRIES MAY OCCUR ACROSS THE
NORTHERN TIER COUNTIES OF THE CWA AS THIS UPPER LEVEL DISTURBANCE
MOVES ACROSS OUR AREA THIS AFTERNOON...BEFORE WE QUICKLY WARM BY
LATE MORNING. STRONG SOUTHWEST FLOW WILL OCCUR THROUGHOUT MOST OF
THE DAY AHEAD OF A STRONG LONGWAVE TROUGH...WARMING US INTO THE
50S ACROSS MOST OF THE REGION.
THE COLD FRONT THAT IS CURRENTLY LOCATED FROM NORTHERN MINNESOTA
AND BACK THROUGH NEBRASKA WILL MOVE THE REGION LATER THIS EVENING.
THE BEST MOISTURE WILL REMAIN JUST TO OUR NORTH...SO NO MEASURABLE
PRECIPITATION IS EXPECTED...JUST A SHOT OF COLD DRY AIR WITH SOME
LIGHT SNOW FLURRIES POSSIBLY BEHIND IT. TEMPERATURES WILL BE SLOW
TO RECOVER ON FRIDAY AS MODERATE CAA WILL CONTINUE INTO THE LATE
AFTERNOON. LOWS WILL DIP INTO THE 20S AND UPPER TEENS BY SATURDAY
MORNING. ALTHOUGH FLOW ALOFT WILL REMAIN NORTHWEST...STRONG
SOUTHWEST WINDS WILL DEVELOP ON THE PERIPHERY OF THE HIGH PRESSURE
AND WARM TEMPERATURES BACK TO NEAR 50 DURING THE DAY SATURDAY.
ANOTHER CLIPPER-TYPE SYSTEM WILL MOVE THROUGH QUICKLY
SATURDAY NIGHT...BRIEFLY TURNING WINDS NORTHWEST BUT ENOUGH TO REALLY
MODIFY THE AIRMASS TOO MUCH. WINDS WILL SHIFT BACK TO THE SOUTH BY
SUNDAY AFTERNOON AND TEMPERATURES WILL BE SLIGHTLY WARMER THAN
SATURDAY.
LONG TERM...MLK DAY THROUGH LATE NEXT WEEK...
MONDAY WILL CONTINUE TO SEE TEMPERATURES SLIGHTLY ABOVE NORMAL AS
WE REMAIN UNDER A WEAK RIDGE OF HIGH PRESSURE. EXPECT TEMPERATURES
TO BE IN THE MID 50S. NORTHWEST FLOW ALOFT WILL ONCE AGAIN BECOME
DOMINANT AND HELP PUSH ANOTHER COLD FRONT THROUGH ON MONDAY
NIGHT. TEMPERATURES TUESDAY THROUGH THE END OF THE WEEK WILL
CONTINUE TO STAY 5 TO 10 DEGREES BELOW NORMAL AS NORTHWEST FLOW
CONTINUES.
AC3
&&
.AVIATION...
18Z TAF CYCLE (16/18Z-17/18Z)
VFR CONDITIONS WILL OCCUR THROUGH THE PERIOD. WINDS STRONG AND GUSTY
FROM THE SW-W THIS AFTERNOON...WESTERLY AROUND 10 KTS TONIGHT...THEN
BECOMING STRONG AND GUSTY FROM THE W-NW FRIDAY MORNING.
JCL
&&
.PRELIMINARY POINT TEMPS/POPS...
MEM 53 29 35 25 / 10 10 0 0
MKL 50 23 31 18 / 10 10 10 0
JBR 51 22 33 21 / 10 10 0 0
TUP 53 28 38 21 / 10 10 10 0
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
955 AM CST THU JAN 16 2014
.DISCUSSION...
SKIES ARE PARTLY CLOUDY ACROSS MUCH OF THE FORECAST AREA THIS
MORNING WITH TEMPERATURES RANGING FROM THE UPPER 20S TO LOWER 40S.
SOME SNOW FLURRIES HAVE BEEN MOVING ACROSS NORTHERN SECTIONS OF
THE FORECAST AREA BUT IT APPEARS THAT LITTLE OF THE ACTIVITY IS
REACHING THE GROUND. AS TEMPERATURES WARM THE THREAT OF SNOW
FLURRIES WILL DIMINISH. WILL UPDATE FORECAST TO REMOVE MORNING
WORDING BUT NO BIG CHANGES ARE NEEDED AT THIS TIME.
ARS
&&
.PREV DISCUSSION... /ISSUED 534 AM CST THU JAN 16 2014/
DISCUSSION...
SHORT TERM...TODAY THROUGH SUNDAY... SLOW WAA HAS BEGUN TO TAKE
PLACE OVERNIGHT AS WINDS HAVE SHIFTED SOUTHERLY. TEMPERATURES
ACROSS THE MID-SOUTH ARE NEAR 30 IN THE WESTERN PART OF THE
FORECAST AREA...WITH 20S TO THE EAST WHERE WINDS HAVEN`T QUITE
PICKED UP YET. TO THE NORTH OF OUR AREA LIGHT SNOW HAS DEVELOPED
NEAR THE ST LOUIS METRO AREA. RADAR TRENDS AND LATEST HRRR MODEL
GUIDANCE SUGGESTS THAT LIGHT FLURRIES MAY OCCUR ACROSS THE
NORTHERN TIER COUNTIES OF THE CWA AS THIS UPPER LEVEL DISTURBANCE
MOVES ACROSS OUR AREA THIS AFTERNOON...BEFORE WE QUICKLY WARM BY
LATE MORNING. STRONG SOUTHWEST FLOW WILL OCCUR THROUGHOUT MOST OF
THE DAY AHEAD OF A STRONG LONGWAVE TROUGH...WARMING US INTO THE
50S ACROSS MOST OF THE REGION.
THE COLD FRONT THAT IS CURRENTLY LOCATED FROM NORTHERN MINNESOTA
AND BACK THROUGH NEBRASKA WILL MOVE THE REGION LATER THIS EVENING.
THE BEST MOISTURE WILL REMAIN JUST TO OUR NORTH...SO NO MEASURABLE
PRECIPITATION IS EXPECTED...JUST A SHOT OF COLD DRY AIR WITH SOME
LIGHT SNOW FLURRIES POSSIBLY BEHIND IT. TEMPERATURES WILL BE SLOW
TO RECOVER ON FRIDAY AS MODERATE CAA WILL CONTINUE INTO THE LATE
AFTERNOON. LOWS WILL DIP INTO THE 20S AND UPPER TEENS BY SATURDAY
MORNING. ALTHOUGH FLOW ALOFT WILL REMAIN NORTHWEST...STRONG
SOUTHWEST WINDS WILL DEVELOP ON THE PERIPHERY OF THE HIGH PRESSURE
AND WARM TEMPERATURES BACK TO NEAR 50 DURING THE DAY SATURDAY.
ANOTHER CLIPPER-TYPE SYSTEM WILL MOVE THROUGH QUICKLY
SATURDAY NIGHT...BRIEFLY TURNING WINDS NORTHWEST BUT ENOUGH TO REALLY
MODIFY THE AIRMASS TOO MUCH. WINDS WILL SHIFT BACK TO THE SOUTH BY
SUNDAY AFTERNOON AND TEMPERATURES WILL BE SLIGHTLY WARMER THAN
SATURDAY.
LONG TERM...MLK DAY THROUGH LATE NEXT WEEK...
MONDAY WILL CONTINUE TO SEE TEMPERATURES SLIGHTLY ABOVE NORMAL AS
WE REMAIN UNDER A WEAK RIDGE OF HIGH PRESSURE. EXPECT TEMPERATURES
TO BE IN THE MID 50S. NORTHWEST FLOW ALOFT WILL ONCE AGAIN BECOME
DOMINANT AND HELP PUSH ANOTHER COLD FRONT THROUGH ON MONDAY
NIGHT. TEMPERATURES TUESDAY THROUGH THE END OF THE WEEK WILL
CONTINUE TO STAY 5 TO 10 DEGREES BELOW NORMAL AS NORTHWEST FLOW
CONTINUES.
AC3
&&
.AVIATION...
12Z TAF CYCLE
VFR CIGS WILL PERSIST AT ALL TERMINALS THROUGH THE TAF PERIOD. THE
BIG STORY THIS CYCLE WILL BE WINDS. SOUTHWEST WINDS SHOULD
INCREASE TO BETWEEN 15-18 KTS WITH GUSTS BETWEEN 25-28 KTS. WINDS
WILL VEER WESTERLY OVERNIGHT AND SLOWLY DIMINISH IN SPEEDS WITH
MOST LOCATIONS DROPPING TO AROUND 10 KTS OR LESS.
JLH
&&
.PRELIMINARY POINT TEMPS/POPS...
MEM 53 29 35 25 / 10 10 0 0
MKL 50 23 31 18 / 10 10 10 0
JBR 51 22 33 21 / 10 10 0 0
TUP 53 28 38 21 / 10 10 10 0
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
534 AM CST THU JAN 16 2014
.UPDATE...
UPDATED FOR THE 12Z AVIATION DISCUSSION.
&&
.PREV DISCUSSION... /ISSUED 434 AM CST THU JAN 16 2014/
DISCUSSION...
.SHORT TERM...TODAY THROUGH SUNDAY... SLOW WAA HAS BEGUN TO TAKE
PLACE OVERNIGHT AS WINDS HAVE SHIFTED SOUTHERLY. TEMPERATURES
ACROSS THE MID-SOUTH ARE NEAR 30 IN THE WESTERN PART OF THE
FORECAST AREA...WITH 20S TO THE EAST WHERE WINDS HAVEN`T QUITE
PICKED UP YET. TO THE NORTH OF OUR AREA LIGHT SNOW HAS DEVELOPED
NEAR THE ST LOUIS METRO AREA. RADAR TRENDS AND LATEST HRRR MODEL
GUIDANCE SUGGESTS THAT LIGHT FLURRIES MAY OCCUR ACROSS THE
NORTHERN TIER COUNTIES OF THE CWA AS THIS UPPER LEVEL DISTURBANCE
MOVES ACROSS OUR AREA THIS AFTERNOON...BEFORE WE QUICKLY WARM BY
LATE MORNING. STRONG SOUTHWEST FLOW WILL OCCUR THROUGHOUT MOST OF
THE DAY AHEAD OF A STRONG LONGWAVE TROUGH...WARMING US INTO THE
50S ACROSS MOST OF THE REGION.
THE COLD FRONT THAT IS CURRENTLY LOCATED FROM NORTHERN MINNESOTA
AND BACK THROUGH NEBRASKA WILL MOVE THE REGION LATER THIS EVENING.
THE BEST MOISTURE WILL REMAIN JUST TO OUR NORTH...SO NO MEASURABLE
PRECIPITATION IS EXPECTED...JUST A SHOT OF COLD DRY AIR WITH SOME
LIGHT SNOW FLURRIES POSSIBLY BEHIND IT. TEMPERATURES WILL BE SLOW
TO RECOVER ON FRIDAY AS MODERATE CAA WILL CONTINUE INTO THE LATE
AFTERNOON. LOWS WILL DIP INTO THE 20S AND UPPER TEENS BY SATURDAY
MORNING. ALTHOUGH FLOW ALOFT WILL REMAIN NORTHWEST...STRONG
SOUTHWEST WINDS WILL DEVELOP ON THE PERIPHERY OF THE HIGH PRESSURE
AND WARM TEMPERATURES BACK TO NEAR 50 DURING THE DAY SATURDAY.
ANOTHER CLIPPER-TYPE SYSTEM WILL MOVE THROUGH QUICKLY
SATURDAY NIGHT...BRIEFLY TURNING WINDS NORTHWEST BUT ENOUGH TO REALLY
MODIFY THE AIRMASS TOO MUCH. WINDS WILL SHIFT BACK TO THE SOUTH BY
SUNDAY AFTERNOON AND TEMPERATURES WILL BE SLIGHTLY WARMER THAN
SATURDAY.
.LONG TERM...MLK DAY THROUGH LATE NEXT WEEK...
MONDAY WILL CONTINUE TO SEE TEMPERATURES SLIGHTLY ABOVE NORMAL AS
WE REMAIN UNDER A WEAK RIDGE OF HIGH PRESSURE. EXPECT TEMPERATURES
TO BE IN THE MID 50S. NORTHWEST FLOW ALOFT WILL ONCE AGAIN BECOME
DOMINANT AND HELP PUSH ANOTHER COLD FRONT THROUGH ON MONDAY
NIGHT. TEMPERATURES TUESDAY THROUGH THE END OF THE WEEK WILL
CONTINUE TO STAY 5 TO 10 DEGREES BELOW NORMAL AS NORTHWEST FLOW
CONTINUES.
AC3
&&
.AVIATION...
12Z TAF CYCLE
VFR CIGS WILL PERSIST AT ALL TERMINALS THROUGH THE TAF PERIOD. THE
BIG STORY THIS CYCLE WILL BE WINDS. SOUTHWEST WINDS SHOULD
INCREASE TO BETWEEN 15-18 KTS WITH GUSTS BETWEEN 25-28 KTS. WINDS
WILL VEER WESTERLY OVERNIGHT AND SLOWLY DIMINISH IN SPEEDS WITH
MOST LOCATIONS DROPPING TO AROUND 10 KTS OR LESS.
JLH
&&
.PRELIMINARY POINT TEMPS/POPS...
MEM 53 29 35 25 / 10 10 0 0
MKL 50 23 31 18 / 10 10 10 0
JBR 51 22 33 21 / 10 10 0 0
TUP 53 28 38 21 / 10 10 10 0
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
434 AM CST THU JAN 16 2014
.DISCUSSION...
...SHORT TERM...TODAY THROUGH SUNDAY...
SLOW WAA HAS BEGUN TO TAKE PLACE OVERNIGHT AS WINDS HAVE SHIFTED
SOUTHERLY. TEMPERATURES ACROSS THE MID-SOUTH ARE NEAR 30 IN THE
WESTERN PART OF THE FORECAST AREA...WITH 20S TO THE EAST WHERE
WINDS HAVEN`T QUITE PICKED UP YET. TO THE NORTH OF OUR AREA LIGHT
SNOW HAS DEVELOPED NEAR THE ST LOUIS METRO AREA. RADAR TRENDS AND
LATEST HRRR MODEL GUIDANCE SUGGESTS THAT LIGHT FLURRIES MAY OCCUR
ACROSS THE NORTHERN TIER COUNTIES OF THE CWA AS THIS UPPER LEVEL
DISTURBANCE MOVES ACROSS OUR AREA THIS AFTERNOON...BEFORE WE
QUICKLY WARM BY LATE MORNING. STRONG SOUTHWEST FLOW WILL OCCUR
THROUGHOUT MOST OF THE DAY AHEAD OF A STRONG LONGWAVE
TROUGH...WARMING US INTO THE 50S ACROSS MOST OF THE REGION.
THE COLD FRONT THAT IS CURRENTLY LOCATED FROM NORTHERN MINNESOTA
AND BACK THROUGH NEBRASKA WILL MOVE THE REGION LATER THIS EVENING.
THE BEST MOISTURE WILL REMAIN JUST TO OUR NORTH...SO NO MEASURABLE
PRECIPITATION IS EXPECTED...JUST A SHOT OF COLD DRY AIR WITH SOME
LIGHT SNOW FLURRIES POSSIBLY BEHIND IT. TEMPERATURES WILL BE SLOW
TO RECOVER ON FRIDAY AS MODERATE CAA WILL CONTINUE INTO THE LATE
AFTERNOON. LOWS WILL DIP INTO THE 20S AND UPPER TEENS BY SATURDAY
MORNING. ALTHOUGH FLOW ALOFT WILL REMAIN NORTHWEST...STRONG
SOUTHWEST WINDS WILL DEVELOP ON THE PERIPHERY OF THE HIGH PRESSURE
AND WARM TEMPERATURES BACK TO NEAR 50 DURING THE DAY SATURDAY.
ANOTHER CLIPPER-TYPE SYSTEM WILL MOVE THROUGH QUICKLY
SATURDAY NIGHT...BRIEFLY TURNING WINDS NORTHWEST BUT ENOUGH TO REALLY
MODIFY THE AIRMASS TOO MUCH. WINDS WILL SHIFT BACK TO THE SOUTH BY
SUNDAY AFTERNOON AND TEMPERATURES WILL BE SLIGHTLY WARMER THAN
SATURDAY.
LONG TERM...MLK DAY THROUGH LATE NEXT WEEK...
MONDAY WILL CONTINUE TO SEE TEMPERATURES SLIGHTLY ABOVE NORMAL AS
WE REMAIN UNDER A WEAK RIDGE OF HIGH PRESSURE. EXPECT TEMPERATURES
TO BE IN THE MID 50S. NORTHWEST FLOW ALOFT WILL ONCE AGAIN BECOME
DOMINANT AND HELP PUSH ANOTHER COLD FRONT THROUGH ON MONDAY
NIGHT. TEMPERATURES TUESDAY THROUGH THE END OF THE WEEK WILL
CONTINUE TO STAY 5 TO 10 DEGREES BELOW NORMAL AS NORTHWEST FLOW
CONTINUES.
AC3
&&
.AVIATION...
06Z TAF SET
VFR CONDITIONS WILL CONTINUE FOR THE NEXT 24 HOURS. WINDS WILL
BEGIN TO TURN AROUND TO THE S OVER THE NEXT SEVERAL HOURS AND INCREASE
TO 10 KTS. AFTER 14Z...SW WINDS OF 12-16 KTS SUSTAINED WITH GUSTS
UP TO 25 KTS WILL OCCUR. DIRECTION WILL SWITCH TO THE W DURING THE
AFTERNOON AT KJBR. ELSEWHERE...WINDS WILL TURN AROUND TO THE W
BETWEEN 23-01Z. SPEED WILL ALSO DECREASE TO 8-10 KTS AFTER 0Z.
KRM
&&
.PRELIMINARY POINT TEMPS/POPS...
MEM 53 29 35 25 / 10 10 0 0
MKL 50 23 31 18 / 10 10 10 0
JBR 51 22 33 21 / 10 10 0 0
TUP 53 28 38 21 / 10 10 10 0
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS SPOKANE WA
531 AM PST Thu Jan 16 2014
.SYNOPSIS...
A much quieter weather pattern will continue over the Inland
Northwest as a ridge of high pressure strengthens over the region.
While fairly benign weather is expected, areas of fog will be
possible each morning through the rest of the week.
&&
.DISCUSSION...
Update to this morning forecast to issue a dense fog advisory.
Although we still cannot see the fog on the satellite fog product
(due to high clouds)...local web cams and suggest the fog is
becoming increasingly widespread. Meanwhile with sub-freezing
temperatures we expect that some of the area roads are quite icy
and could make for a hazardous morning commute. Looks like most of
the fog is concentrated around the Spokane area into Post Falls
with the poorest visibilities found on the West Plains. The 12z
Spokane sounding shows a very pronounced...yet shallow inversion.
This suggests the fog should (emphasis on should) be able to
dissipate by midday...and this notion is finally supported by the
latest HRRR model run. We will go with a 11am expiration time for
now however there is a chance it may have to be extended as the
dprog/dt from the hourly model is showing an slowing clearing trend.
&&
.AVIATION...
12Z TAFS: Cloud free sky has allowed for optimal surface cooling and
an inversion to set up over the region. This has produced wide
spread fog and low level stratus with the airfield minimums being
reached at KGEG, KSFF, KCOE. These locations are expected to be near
the minimums until 18Z. The other TAF sites are expected to remain
MVFR with periods of stratus near the surface. With no major changes
to the overall weather pattern expected, this cycle of weather can
expect to return Thursday night. /JDC
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 37 27 37 28 35 28 / 0 0 0 0 0 0
Coeur d`Alene 39 27 38 29 36 27 / 0 0 0 0 0 0
Pullman 45 30 41 31 42 31 / 0 0 0 0 0 0
Lewiston 41 30 38 29 42 29 / 0 0 0 0 0 0
Colville 41 24 37 30 35 30 / 0 0 0 0 0 0
Sandpoint 40 25 36 27 36 28 / 0 0 0 0 0 0
Kellogg 39 28 40 29 40 29 / 0 0 0 0 0 0
Moses Lake 42 24 37 26 37 26 / 0 0 0 0 0 0
Wenatchee 42 28 36 29 37 27 / 0 0 0 0 0 0
Omak 36 23 34 28 34 26 / 0 0 0 0 0 0
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Dense Fog Advisory until 11 AM PST this morning for Coeur
d`Alene Area.
WA...Air Stagnation Advisory until 10 AM PST Saturday for East Slopes
Northern Cascades-Lower Garfield and Asotin Counties-Moses
Lake Area-Northeast Mountains-Okanogan Highlands-Okanogan
Valley-Spokane Area-Upper Columbia Basin-Washington Palouse-
Waterville Plateau-Wenatchee Area.
Dense Fog Advisory until 11 AM PST this morning for Spokane Area.
&&
$$
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
345 PM CST THU JAN 16 2014
.TONIGHT AND FRIDAY...FORECAST CONFIDENCE IS MEDIUM.
AREA OF LIGHT SNOW SHOWERS WILL CONTINUE TO ROTATE EASTWARD THROUGH
THE AREA LATE THIS AFTERNOON...FOLLOWING THE PASSING 500 MB
SHORTWAVE TROUGH. HRRR HAS A DECENT HANDLE ON THIS...AND SHIFTS THIS
AREA EAST OF THE LAKE MICHIGAN SHORELINE BY 02Z FRIDAY. EXPECT LIGHT
ACCUMULATIONS UP TO AROUND 1/2 INCH IN ANY HEAVIER ACTIVITY THROUGH
EARLY EVENING.
SOME QUESTION AS TO WHAT WILL HAPPEN WITH ANY SNOW SHOWER ACTIVITY
THIS EVENING. HRRR AND THE SYNOPTIC MODELS ARE INDICATING A BREAK IN
THE SNOW SHOWER ACTIVITY...AS AREA FORECAST SOUNDINGS SHOW DRYING IN
THE LOWER LEVELS IN DENDRITE ZONE AS THE EVENING GOES ON. THERE IS
SOME WEAK ACTIVITY UPSTREAM...WITHIN CYCLONIC FLOW AT 500 MB. NOT
MUCH IN THE WAY OF FORCING FOR UPWARD VERTICAL MOTION...SO THE DRY
PERIOD MAY INDEED OCCUR.
FOR NOW...WENT WITH LOWER POPS IN THE NORTHWEST HALF OF THE AREA
BETWEEN 02Z AND 06Z FRIDAY...WITH DRY CONDITIONS IN THE SOUTHEAST
HALF. THIS MAY NEED TO BE EXPANDED FURTHER NORTHWEST IF DRYING
OCCURS AS SHOWN IN MODELS. CONTINUED TO MENTION BLOWING SNOW IN THE
EVENING...WITH GUSTY NORTHWEST WINDS EXPECTED TO OCCUR BEHIND THE
EASTWARD ADVANCING COLD FRONT. SOME DRIFTING ISSUES MAY OCCUR ON
NORTH TO SOUTH ROADS THIS EVENING.
AREA FORECAST SOUNDINGS SHOW MOISTURE INCREASING LATER TONIGHT INTO
FRIDAY IN THE LOW LEVELS...WITHIN DENDRITE ZONE. THIS CORRESPONDS
WITH NEXT 500 MB VORTICITY MAXIMUM ROTATING SOUTHEASTWARD THROUGH
THE AREA LATER TONIGHT...WITH ANOTHER AFFECTING THE EAST FRIDAY
AFTERNOON. SO...BROUGHT POPS BACK INTO THE SCATTERED RANGE DURING
THIS PERIOD. THINGS DRY OUT IN THE WEST FRIDAY AFTERNOON...SO
BROUGHT DRY CONDITIONS THERE. ACCUMULATIONS UP TO AN INCH ARE
POSSIBLE LATER TONIGHT INTO FRIDAY.
COLD TEMPERATURES ARE EXPECTED TONIGHT...AS 925 MB TEMPERATURES DROP
INTO THE MID TEENS BELOW ZERO CELSIUS. THESE VALUES LINGER ON
FRIDAY. WENT SINGLE DIGITS ABOVE ZERO SOUTH AND CENTRAL...WITH 10 TO
12 ABOVE NORTH. HIGHS FRIDAY SHOULD ONLY REACH THE MID TEENS
WEST...TO THE LOWER 20S FAR EAST. WIND CHILLS WILL DROP TO THE 10 TO
15 BELOW ZERO RANGE ACROSS THE SOUTH LATER TONIGHT AND EARLY FRIDAY.
.SHORT TERM...FRIDAY NIGHT THROUGH SUNDAY.
FRIDAY NIGHT AND SATURDAY...FORECAST CONFIDENCE MEDIUM.
RIDGING BRINGS A QUIET FRIDAY NIGHT THEN FOCUS IS ON
VIGOROUS...COMPACT SHORT WAVE DRIVEN BY THE UPPER LEVEL DIVERGENCE
IN THE LEFT EXIT REGION OF A 160 KNOT JET DROPPING A SURFACE LOW
DURING THE DAY SATURDAY ACROSS THE REGION FROM CENTRAL MN...OVER THE
VICINITY OF ROCHESTER/LA CROSSE TO NEAR OR SOUTH OF CHICAGO BY 00Z
SUNDAY
12Z ECMWF NOW MORE IN LINE WITH THE 12Z RUNS OF THE GFS AND GEMNH
WHICH ARE SLIGHTLY FASTER AND FARTHER WEST WITH THE SURFACE LOW THAN
12Z NAM AND THE 00Z ECMWF.
NAM AND GEM KEEP WAA PCPN OUT OF CWA PRIOR TO 12Z SATURDAY...WITH
GFS AND ECMWF...WHICH BRING SNOW INTO FAR WESTERN COUNTIES BETWEEN
09Z AND 12Z. WILL ACKNOWLEDGE WITH A SLIGHT CHANCE OF SNOW IN THE
FAR WEST AFTER 09Z.
RAISED POPS TO CATEGORICAL WITH IMPRESSIVE 850-300MB Q-VECTOR
CONVERGENCE CROSSING THE REGION...WITH OMEGA OF 8 TO 10 MICROBARS
INTERSECTING THE DENDRITE GROWTH ZONE.
EVERYONE WILL SEE ACCUMULATING SNOW DURING THE MORNING...THEN
TAPERING OFF FROM NW TO SE DURING THE AFTERNOON. STILL A QUESTION TO
AMOUNTS. NAM THE OUTLIER WITH HIGHER QPF...WHICH HAS BEEN A
REPEATING TREND THIS WINTER. WENT WITH A CONSENSUS BLEND OF QPF AND
SNOW RATIOS WHICH YIELDS FROM 2 TO 2.5 INCHES IN THE FAR SW AND FAR
NE...UP TO 4 INCHES IN THE SE CWA WITH A CONSENSUS LOW TRACK
BRINGING THE AXIS OF HIGHER AMOUNTS ALONG AND EITHER SIDE OF A
DELLS...WATERTOWN TO KENOSHA LINE. IF THE LOW TRACKS FARTHER WEST
THAN CURRENT FORECAST...IT COULD BRING A PERIOD OF LAKE-ENHANCED/
LAKE-EFFECT SNOW TO THE EAST.
LOWS EARLY FRIDAY NIGHT WITH 925 MB THERMAL TROUGH CENTERED OVER
REGION AT 06Z THEN INCREASING CLOUDS AND TEMPS WITH WAA BRING STEADY
TEMPS OVERNIGHT...WITH A SLIGHT RISE TOWARD DAYBREAK. DIFFERING
TRACKS OF SYSTEM BRINGS VARYING DEGREES OF WARMTH INTO THE FORECAST
AREA. BLENDED TEMPS BRING HIGHS AROUND 20 TO 25.
SATURDAY NIGHT AND SUNDAY...FORECAST CONFIDENCE MEDIUM.
DRY WEATHER WITH WEAK RIDGING SATURDAY NIGHT AND SUNDAY. TEMPS
SLOWLY COOL WITH WEAK COLD AIR ADVECTION THROUGH AROUND
MIDNIGHT...THEN WARM AIR ADVECTION AHEAD OF DEVELOPING SURFACE LOW
NORTH OF LAKE SUPERIOR AS CLOSED UPPER LOW AROUND HUDSON BAY
DEEPENS...BRINGS STEADY TEMPS WITH ANOTHER SLOW RISE TOWARD
DAYBREAK. MODELS DIFFER WITH SPEED OF TRAILING COLD FRONT DROPPING
THROUGH STATE ON SUNDAY...WITH THE GFS BRINGING -8C TO -10C 925MB
TEMPS INTO SRN WI BY 18Z SUNDAY...WITH THE NAM AND ECMWF STILL AT OR
ABOVE 0C AT 00Z MONDAY. A CONSENSUS YIELDS HIGH TEMPERATURES IN THE
UPPER 20S TO LOWER 30S...BUT IF THE WARMER NAM AND ECMWF
VERIFY...COULD SEE TEMPS AT LEAST 5 DEGREES WARMER.
.LONG TERM...SUNDAY NIGHT THROUGH THURSDAY. FORECAST CONFIDENCE
LOW.
MODELS IN REASONABLE AGREEMENT TO DEGREE OF COLD AIR BEHIND COLD
FRONT FOR SUNDAY NIGHT INTO THE EARLY PORTION OF NEXT WEEK. 925 MB
TEMPS FALL TO -20C TO -25C BY TUESDAY MORNING DEPENDING ON MODEL.
ADJUSTED ALL BLEND TEMPERATURES DOWNWARD TO REFLECT COLDER LOOK. THE
LOW CHANCE/SLIGHT CHANCE POPS ON MONDAY/MONDAY NIGHT DUE TO MORE
SOUTHERLY TRACK OF SURFACE LOW ON GEM...BUT ENOUGH SHORT WAVE ENERGY
MOVING THROUGH THE REGION UNDER CLOSED HUDSON BAY LOW TO WARRANT
POPS. MODELS KEEP AREA DRY WITH SURFACE HIGH PRESSURE TUESDAY
THROUGH WEDNESDAY NIGHT...BUT CONTINUED PARADE OF SHORT WAVE ENERGY
COULD BRING AT LEAST ROUNDS OF FLURRIES/LIGHT SNOW SHOWERS. BETTER
CHANCE COMES WITH DEEPER WAVE THURSDAY/FRIDAY...THOUGH DIFFERING
MODEL TIMING SMEARS LOW CHANCE POPS ACROSS THE END OF THE
EXTENDED.
&&
.AVIATION/00Z TAFS/...
VISIBILITIES BELOW ALTERNATE MINIMUMS WITH CEILINGS OF 1000 TO 1500
FEET ABOVE GROUND LEVEL ARE EXPECTED WITH THE SNOW SHOWERS THROUGH
THE EARLY EVENING HOURS. SOUTHWEST WINDS WILL SHIFT WEST NORTHWEST
AND BECOME GUSTY AT MADISON BY 22Z THURSDAY...AND AT THE EASTERN
SITES BY 00Z FRIDAY. SOME BLOWING SNOW AND DRIFTING SNOW IS EXPECTED
ON NORTH TO SOUTH RUNWAYS. A QUICK 1/2 INCH OR SO IN A HALF HOUR IS
POSSIBLE IN ANY OF THE HEAVIER SNOW SHOWERS.
THERE SHOULD BE A LULL IN THE SNOW SHOWER ACTIVITY FROM 02Z TO 06Z
FRIDAY...WITH VFR VISIBILITIES AND MVFR CEILINGS. GUSTY WEST
NORTHWEST WINDS WILL CONTINUE TO BRING SOME BLOWING AND DRIFTING
SNOW...BUT SHOULD NOT REDUCE VISIBILITIES MUCH.
SNOW SHOWERS SHOULD RETURN AFTER 06Z FRIDAY...LINGERING INTO THE
MORNING HOURS AT MADISON...AND THE AFTERNOON AT THE EASTERN SITES.
VISIBILITIES SHOULD REMAIN AROUND ALTERNATE MINIMUMS. AGAIN...COULD
SEE A QUICK 1/4 TO 1/2 INCH IN A HALF HOUR WITH ANY HEAVIER SNOW
SHOWERS...TOTALS UP TO AN INCH AT BEST. GUSTY WEST NORTHWEST WINDS
WILL LINGER...BUT WILL SLOWLY WEAKEN IN THE AFTERNOON.
&&
.MARINE...
SMALL CRAFT ADVISORY CONTINUES UNTIL MIDNIGHT TONIGHT FOR THE
NEARSHORE WATERS OF LAKE MICHIGAN. WINDS WILL SHIFT TO THE WEST
NORTHWEST AND BECOMING GUSTY ONCE AGAIN BY 00Z FRIDAY...AFTER A
STRONG COLD FRONT MOVES THROUGH. THESE WINDS WILL LINGER THROUGH THE
EVENING HOURS...BEFORE FALLING SLIGHTLY BELOW CRITERIA BY MIDNIGHT.
ANY HIGH WAVES TOWARD THE OPEN WATERS THIS EVENING WILL SUBSIDE BY
LATER TONIGHT.
HOWEVER...THE SMALL CRAFT ADVISORY MAY NEED TO BE EXTENDED THROUGH
FRIDAY...AS THE PRESSURE GRADIENT TIGHTENS UP AGAIN FRIDAY MORNING
INTO THE AFTERNOON. SOME GUSTS TO 25 KNOTS ARE POSSIBLE...THOUGH
OFFSHORE FLOW WILL KEEP HIGH WAVES OVER THE OPEN WATERS.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...SMALL CRAFT ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR LMZ643>646.
&&
$$
TONIGHT/FRIDAY AND AVIATION/MARINE...WOOD
FRIDAY NIGHT THROUGH THURSDAY...REM
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
938 PM MST FRI JAN 17 2014
.UPDATE...
&&
.SHORT TERM...WINDS HAVE DIMINISHED AT LOWER ELEVATIONS AND
TEMPERATURES HAVE BEEN BOBBING AROUND IN MANY AREAS AS THERE IS
STILL ENOUGH GRADIENT TO KEEP MOST PLACES FROM COMPLETELY
DECOUPLING. DIA DROPPED TO 29 DURING A BRIEF LULL BEFORE THE WEST
WIND PICKED UP AND IT WARMED UP AGAIN. WIND SHELTERED/LOW LYING
SPOTS LIKE GREELEY...LIMON AND KREMMLING ARE COLD AND SHOULD KEEP
DROPPING WHILE OTHER AREAS WILL KEEP A LITTLE WIND AND NOT FALL
MUCH FURTHER. MADE SOME MINOR ADJUSTMENTS TO TONIGHTS LOWS.
LOOKING LIKE A LITTLE MORE WIND NEAR THE EASTERN BORDER SATURDAY
AFTERNOON...NUDGED THE FORECAST TOWARD THE GFS MOS AND RUC WHICH
ARE A BIT WINDIER AND DRIER OUT THERE. WINDS ALONG THE FRONT RANGE
MAY BE TRICKY AS THE FLOW WILL BE BLOCKED BY THE MOUNTAINS...NOT
WESTERLY ENOUGH TO STAY WEST AND NOT NORTHERLY ENOUGH TO JUST BE
NORTH. THERE WILL PROBABLY BE SOME CHAOTIC EDDIES WITH GENERALLY
LIGHT SPEEDS...PERHAPS EVENTUALLY A SIMPLER NORTH TO NORTHEAST
TURNING AWAY FROM THE STRONG NNW WINDS ON THE PLAINS IN THE
AFTERNOON. SPEEDS WILL START TO DECREASE IN THE AFTERNOON AS THE
GRADIENT FALLS OFF. ADDED A LITTLE BLOWING DUST IN THE NORTHEAST
CORNER...IT SHOULD NOT BE AS BAD AS THURSDAY BUT THERE WILL LIKELY
BE SOME.
.AVIATION...VFR THROUGH SATURDAY. WEST WINDS AROUND 10 KNOTS
SHOULD TREND MORE SOUTHERLY AT KDEN/KAPA LATER THIS EVENING. WINDS
WILL LIKELY TURN NORTHWEST AND EVENTUALLY MORE NORTHERLY DURING
THE DAY SATURDAY. EXPECT SOME VARIABILITY IN DIRECTION ESPECIALLY
IN THE AFTERNOON AS SOME KIND OF EDDY WILL FORM OFF OF THE STRONG
NORTHWEST WINDS FURTHER EAST ON THE PLAINS. UPCOMING TAFS WILL
SHOW SOME EASTERLY COMPONENT LATER IN THE DAY. SPEEDS GENERALLY
EXPECTED TO BE LIGHT...THOUGH IF THE CIRCULATION GETS ORGANIZED
COULD BE UP TO 15 KNOTS.
&&
.PREV DISCUSSION... /ISSUED 334 PM MST FRI JAN 17 2014/
SHORT TERM...MODERATE NORTHWEST FLOW ALOFT ACROSS REGION WITH
UPPER RIDGE MOVING INTO THE GREAT BASIN AND LARGE UPPER TROUGH
ACROSS MIDWEST. WINDS A BIT BREEZY IN AND NEAR FOOTHILLS AS WELL
AS ACROSS THE HIGHER RIDGES...WITH A FEW GUSTS AROUND 35 MPH IN
WIND PRONE AREAS. ACROSS PLAINS...WINDS MUCH LIGHTER WITH WEAK
ANTICYCLONE IN DENVER AREA. SOME HIGH LEVEL MOISTURE SPREADING
ACROSS AREA WITH NO SIGN OF WAVE CLOUD. RIDGE WILL CONTINUE TO
BUILD INTO THE GREAT BASIN THIS EVENING WITH NORTHWEST FLOW ALOFT
CONTINUING. WINDS WILL REMAIN A BIT GUSTY OVER THE HIGHER RIDGES
AND ALONG FOOTHILLS...WITH SOME GUSTS TO 40 MPH POSSIBLE. BREEZY
CONDITIONS WILL ALSO EXIST NEAR THE FOOTHILLS AS DRAINAGE WINDS
BECOME ENHANCED BY THE WESTERLIES. OTHERWISE...MAINLY CLEAR SKIES
WILL PREVAIL WITH LIGHT DRAINAGE WINDS. ON SATURDAY...NORTHWEST
FLOW ALOFT WILL CONTINUE AS UPPER RIDGE OVER GREAT BASIN BUILDS
TOWARD COLORADO AND LARGE UPPER TROUGH REMAINS OVER THE MIDWEST.
MODELS SHOW A WEAK MID LEVEL SHORTWAVE MOVING ACROSS THE NORTHERN
AND CENTRAL PLAINS STATES DURING THE DAY. AIRMASS WILL REMAIN DRY
AND SLIGHTLY WARMER. COMBINATION OF MIXING AND INCREASING SURFACE
GRADIENT WILL PRODUCE GUSTY WINDS ACROSS THE FAR NORTHEAST PLAINS
BETWEEN 15Z AND 21Z. COULD SEE SOME GUSTS APPROACHING 45 MPH.
FURTHER WEST...GRADIENT WILL BE WEAKER WITH LESS WIND. GUSTY WINDS
WILL STILL BE POSSIBLE OVER THE HIGHER RIDGES AND ALONG FOOTHILLS.
TEMPERATURE AND THICKNESS PROGS SUGGEST HIGHS WARMING ABOUT 2 TO 4
DEGREES F. FROM TODAY`S READINGS. THUS HIGHS TO WARM BACK INTO THE
MIDDLE 50S ACROSS THE PLAINS.
LONG TERM...A PERSISTENT UPPER RIDGE OVER THE WESTERN U.S. AND
WESTERN CANADA WILL LEAVE COLORADO DRY AND MILD THROUGH THE BULK
OF NEXT WEEK. EARLY IN THE PERIOD...THE WARMEST TEMPERATURES OF
THE WEEK MAY BE SUNDAY AFTERNOON. ON SUNDAY NIGHT...THERE ARE
INDICATIONS THAT A WEAK SURGE OF COOL AIR WILL DROP INTO THE STATE
SUNDAY NIGHT AND MONDAY MORNING. HIGH TEMPERATURES COULD BE UP TO
10 DEGREES COOLER ON MONDAY. THROUGH THE REST OF THE WEEK...THE
WEAK NORTHWEST FLOW ALOFT AND A SURFACE HIGH PRESSURE RIDGE OVER
THE NORTHERN PLAINS WILL KEEP FEEDING MODIFIED CANADIAN AIR INTO
THE STATE. THIS WILL TEND TO KEEP TEMPERATURES COOLER THAN IF
STRONGER NORTHWEST FLOW WERE IN PLACE. TEMPERATURES WILL STILL BE
WARMER THAN CLIMATOLOGY THROUGH THE PERIOD. THE AIRMASS WILL
REMAIN DRY...LEADING TO MOSTLY SUNNY SKIES EACH DAY.
AT THE END OF NEXT WEEK...THE GFS AND ECMWF ARE NOW SHOWING
AGREEMENT IN BRINGING SOME SORT OF SHORT WAVE ACROSS THE STATE. AS
BOTH MODELS INSIST ON PRODUCING SOME QPF AS THE SHORT WAVE MOVES
ACROSS...WILL INTRODUCE A SLIGHT CHANCE OF SNOW FOR THE MOUNTAIN
AREAS. THIS COULD HAPPEN ANYTIME FROM THURSDAY AFTERNOON THROUGH
FRIDAY...SO WILL COVER THE ENTIRE 30-36 HOUR PERIOD WITH THE
SLIGHT CHANCE POPS.
AVIATION...VFR TO CONTINUE WITH UNLIMITED CEILINGS. WEAK
ANTICYCLONE KEEPING LIGHT EASTERLY WINDS AT KDEN AND KAPA WITH
WESTERLY WINDS AT KBJC. DRAINAGE WINDS TO DEVELOP BY 03Z WITH
SOUTHERLY WINDS AT KDEN AND KAPA AND WESTERLY AT KBJC. SPEEDS
AROUND 8 KTS TO PREVAIL...WITH SOME GUSTS TO 20 KTS POSSIBLE AT
KBJC. WINDS TO WEAKEN BY 15Z SATURDAY AND SHIFT TO THE NORTHWEST.
SLIGHT CHANCE OF ANOTHER WEAK ANTICYCLONE DEVELOPING NORTH OF
DENVER BY 20Z WITH LIGHT NORTHEAST TO EAST WINDS AT KDEN AND KAPA.
FOR NOW WILL KEEP LIGHT NORTHWESTERLY WINDS AT THE AREA AIRPORTS
THROUGH 00Z.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...D-L
LONG TERM....DANKERS
AVIATION/UPDATE...GIMMESTAD
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
410 AM EST SAT JAN 18 2014
.SYNOPSIS...
A COLD FRONT AND ASSOCIATED AREA OF LOW PRESSURE WILL CONTINUE
TO MOVE TO OUR NORTHEAST TODAY. A WEAKENING AREA OF LOW PRESSURE AND
ASSOCIATED COLD FRONT WILL QUICKLY MOVE ACROSS THE AREA ON SUNDAY. A
STRONGER AREA OF LOW PRESSURE WILL SWING EASTWARD ACROSS SOUTHERN
CANADA SUNDAY NIGHT INTO MONDAY, DRAGGING A FRONTAL BOUNDARY ACROSS
THE EAST COAST SUNDAY NIGHT INTO MONDAY. COLD HIGH PRESSURE WILL
BUILD TO OUR SOUTHWEST TUESDAY INTO EARLY WEDNESDAY, BEFORE ANOTHER
LOW PRESSURE SYSTEM AND ASSOCIATED FRONTAL BOUNDARIES AFFECT THE
AREA WEDNESDAY NIGHT INTO THURSDAY. HIGH PRESSURE WILL RETURN TO THE
EAST COAST FOR FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
DECENT BAND PUSHING THROUGH THE NORTHERN PORTIONS OF OUR CWA AT THIS
EARLY MORNING HOUR THOUGH IT DOES APPEAR WORSE THAN IT PROBABLY
IS...BRIGHT BANDING. THERE IS SOME WEAK 850-700MB FGEN ASSOCIATED
WITH A PASSING LOW-LEVEL WARM FRONT AS DESIGNATED BY TEMPERATURES
ACROSS SOUTHERN DELMARVA INCHING CLOSE TO 50F WHILE FURTHER NORTH
ARE BARELY AROUND FREEZING.
DECIDED TO KEEP THE ADVISORY GOING THROUGH AT LEAST THE NEXT
FORECAST UPDATE THOUGH IT IS LOOKING RATHER BENIGN AT THIS POINT.
BOTH THE RUC AND THE HRRR ARE FAIRLY CONSISTENT KEEPING THE BEST QPF
TO OUR WEST WITH THE NEGATIVE MID-LEVEL TROUGH AND SURFACE COLD
FRONT. AS THE TROUGH SHEARS ALONG TOWARDS THE NORTHEAST IT LOOKS TO
OPEN UP AND BECOME FLATTER WHICH SHOULD BRING AN END TO A MAJORITY
OF THE PRECIPITATION. DROPPED THE AMOUNT OF QPF FOR THIS MORNING
WHICH ULTIMATELY DECREASED THE SNOW AMOUNTS ACROSS THE REGION.
THOUGH THERE IS PRETTY GOOD OMEGA WITHIN THE SNOW GROWTH ZONE THE
SYSTEM IN GENERAL IS VERY QUICK MOVING NOT ALLOWING FOR MORE THAN A
COUPLE INCHES ACROSS THE HIGHER ELEVATIONS EARLY THIS MORNING.
THE AFOREMENTIONED COLD FRONT IS RIGHT ON OUR WESTERN DOORSTEP AND
THERE ARE A FEW GUSTS CLOSE TO 20MPH NOW THOUGH THE DRIER AIR IS
STILL WELL TO THE WEST SO IT WILL TAKE A BETTER PART OF THE MORNING
TO SEE DEWPOINTS DROP. THE FRONT WILL BE OFF TO THE EAST THIS
AFTERNOON GIVING WAY TO STRONG WESTERLY WINDS WHICH WILL HAVE THE
BIGGEST IMPACT FOR TODAY`S SENSIBLE WEATHER. THE AIRMASS CONTINUES TO
COOL AND WE ARE EXPECTING DAYTIME HIGHS TO REACH INTO THE LOW TO
MID-30S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SUNDAY/...
WE SHOULD BE BETWEEN WAVES, AGAIN, TONIGHT WITH WEAK RIDGING
BUILDING IN, THOUGH IT WON`T LAST LONG. THE NEXT CLIPPER SHOULD DIG
DEEPER TO OUR WEST LATE TONIGHT TO QUICKLY RUSH TOWARDS THE EAST.
MODELS ARE DECENT AGREEMENT THAT ALL PRECIPITATION SHOULD HOLD OFF
UNTIL LATER SUNDAY MORNING SO WE KEEP THE FORECAST DRY OVERNIGHT
WITH CLEARING CONDITIONS. THIS SHOULD ALLOW FOR DECENT RADIATIONAL
COOLING CONDITIONS IN OUR SHELTERED LOCATIONS. A BLEND OF THE
MET/MAV WAS USED FOR LOWS.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
THE EXTENDED FORECAST CONTINUES TO BE DOMINATED BY BROAD TROUGHING
ACROSS THE EAST COAST, WITH SEVERAL SHORT WAVES AND CLIPPER SYSTEMS
EXPECTED TO AFFECT THE AREA. NONE OF THE SYSTEMS LOOK TO BE ABLE TO
PRODUCE WIDESPREAD PRECIPITATION ACROSS THE AREA. ABOVE NORMAL
TEMPERATURES ARE EXPECTED TO START OFF THE PERIOD, FOLLOWED BY QUITE
A BIT OF A COOL DOWN AS COLD POLAR AIR INFILTRATES THE AREA.
THE FIRST OF THE SHORT WAVES/CLIPPER SYSTEMS IS EXPECTED TO MOVE
THROUGH THE AREA EARLY SUNDAY. WE WILL MAINTAIN A SLIGHT CHANCE OF
PRECIPITATION AT THIS POINT, ALTHOUGH MODELS ARE BECOMING LESS
EXCITED ABOUT MEASURABLE PRECIP ACROSS THE AREA AS COMBINED
MOISTURE/LIFT ARE LACKING SOME AS THE SYSTEM WEAKENS AS IT MOVES
INTO OUR AREA. SUNDAY IS EXPECTED TO BE ABOVE NORMAL AS THICKNESSES
INCREASE BEHIND THE DEPARTING SHORT WAVE AND SKIES MAY CLEAR SOME TO
ALLOW SOME WARMING. SUNDAY NIGHT IS EXPECTED TO REMAIN DRY AND ABOVE
NORMAL AS THICKNESSES CONTINUE TO INCREASE SOME WITH A SOUTHWEST
FLOW ALOFT.
ON SUNDAY NIGHT INTO MONDAY, AN AREA OF LOW PRESSURE WILL BE MOVING
THROUGH SOUTHERN CANADA, PULLING A COLD FRONT TOWARD OUR AREA. THE
FRONTAL BOUNDARY IS EXPECTED TO MOVE THROUGH THE AREA DURING THE DAY
MONDAY INTO MONDAY EVENING. THE GREATEST POTENTIAL FOR PRECIPITATION
LOOKS TO REMAIN TO OUR NORTH AS THE STRONGEST MOISTURE/LIFT
COMBINATION DOES NOT LOOK TO MAKE IT INTO OUR AREA. HOWEVER, WE WILL
MAINTAIN A SLIGHT CHANCE ACROSS OUR NORTHERN THIRD OF THE FORECAST
AREA AS GUIDANCE DOES INDICATE MINIMAL QPF ACROSS OUR FAR NORTHERN
ZONES. TEMPERATURES MONDAY ARE EXPECTED TO BE SEVERAL DEGREES ABOVE
NORMAL AHEAD OF THE FRONTAL BOUNDARY, BUT BEHIND THE FRONT,
TEMPERATURES WILL BE TAKING A NOSE DIVE. LOWS OVERNIGHT MONDAY INTO
TUESDAY MORNING WILL LIKELY FALL BELOW NORMAL.
TUESDAY IS CURRENTLY EXPECTED TO REMAIN PRECIPITATION FREE ACROSS
THE AREA. AN AREA OF LOW PRESSURE IS FORECAST TO DEVELOP ALONG THE
FRONTAL BOUNDARY TO OUR EAST, BUT MAY DEVELOP FAR ENOUGH OFFSHORE TO
KEEP THE PRECIPITATION AWAY FROM OUR AREA. HIGH PRESSURE WILL
BRIEFLY TRY TO BUILD INTO THE AREA LATE TUESDAY NIGHT INTO
WEDNESDAY, SO DRY WEATHER IS EXPECTED TO CONTINUE. THE BIG THING TO
NOTE FOR THIS PERIOD WILL BE THE COLD ONCE AGAIN. TEMPERATURES FROM
TUESDAY NIGHT-WEDNESDAY NIGHT COULD BE AT LEAST 10-15 DEGREES BELOW
NORMAL. THIS COMBINED WITH GUSTY WINDS WILL GREAT VERY LOW WIND
CHILLS ONCE AGAIN ACROSS THE AREA.
ANOTHER CLIPPER TYPE SYSTEM IS EXPECTED TO AFFECT THE AREA WEDNESDAY
NIGHT INTO THURSDAY. AGAIN, MODELS AREN`T IN AGREEMENT WITH QPF
AMOUNTS AS THE GFS HAS MINIMAL AMOUNTS, IF ANY, WHILE THE ECMWF HAS
QUITE A BIT MORE. FOR NOW WE WILL KEEP SLIGHT CHANCE DUE TO
UNCERTAINTY, AND LET LATER FORECAST INCREASE IF GREATER CONFIDENCE
BUILDS. TEMPERATURES WILL REMAIN COLD AND BELOW NORMAL THURSDAY AND
FRIDAY, ALTHOUGH A SLIGHT WARMING TREND BEGINS TO DEVELOP.
&&
.AVIATION /09Z SATURDAY THROUGH WEDNESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
TODAY...VFR OUTSIDE OF RDG/ABE EARLY THIS MORNING. AREAS OF SNOW
SHOWERS NORTH AND WEST OF ABE/RDG WILL CONTINUE TO MOVE OFF TOWARDS
THE NORTH ALLOWING THESE TERMINALS TO REBOUND BACK TO VFR. OTHERWISE
A STIFF GUSTY WESTERLY WIND IS EXPECTED TODAY WITH GUSTS UPWARDS OF
25 TO POSSIBLY 30 KNOTS.
TONIGHT...VFR. LIGHT AND VARIABLE WINDS WITH CLEARING SKIES.
OUTLOOK...
SUNDAY-SUNDAY NIGHT...MOSTLY VFR. LOWER CIGS/VSBY POSSIBLE SUNDAY
MORNING IF SHOWERS OCCUR. GUSTY SOUTHWEST WINDS AROUND 20 KT DURING
THE DAY.
MONDAY-MONDAY NIGHT...MOSTLY VFR. LOWER CIGS/VSBY POSSIBLE MONDAY IF
SHOWERS OCCUR, MAINLY NORTHERN TAF SITES. GUSTY WEST-SOUTHWEST WINDS
20-25 KT DURING THE DAY.
TUESDAY-WEDNESDAY...MOSTLY VFR. GUSTY NORTH-NORTHWEST WINDS 15-20
KT.
&&
.MARINE...
SMALL CRAFT CONTINUES ACROSS ALL OUR WATERS AS A QUICK MOVING COLD
FRONT APPROACHES FROM THE WEST THIS MORNING. AS THE FRONT PASSES
THROUGH STRONG GUSTY WESTERLY WINDS WILL KICK IN...GUSTS AROUND 30
KNOTS THROUGH THE LATE EVENING HOURS. WINDS AND SEAS WILL RELAX A
BIT TONIGHT, POSSIBLY BELOW SCA CRITERIA, BUT SHOULD BEGIN TO CLIMB
UPWARDS AGAIN LATE SUNDAY MORNING.
OUTLOOK...
SUNDAY...SCA IN EFFECT.
SUNDAY NIGHT...SCA CONDITIONS EXPECTED, POSSIBLE NEAR GALE FORCE
GUSTS.
MONDAY-TUESDAY...SCA CONDITIONS LIKELY TO REMAIN.
TUESDAY NIGHT...SCA CONDITIONS POSSIBLE EARLY, BEFORE DIMINISHING
OVERNIGHT.
WEDNESDAY...SUB-ADVISORY CONDITIONS EXPECTED.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...WINTER WEATHER ADVISORY UNTIL 10 AM EST THIS MORNING FOR
PAZ054-055.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EST SUNDAY FOR ANZ430-431-
451>455.
SMALL CRAFT ADVISORY FROM 9 AM THIS MORNING TO 6 PM EST SUNDAY
FOR ANZ450.
&&
$$
SYNOPSIS...ROBERTSON
NEAR TERM...HEAVENER
SHORT TERM...HEAVENER
LONG TERM...ROBERTSON
AVIATION...HEAVENER/ROBERTSON
MARINE...HEAVENER/ROBERTSON
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
316 AM CST SAT JAN 18 2014
.DISCUSSION...
640 PM CST
EARLY EVENING UPDATE...
MINOR CHANGES TO FORECAST GRIDS/ZFP TO RAISE POPS ACROSS NORTHEAST
IL THROUGH EARLY EVENING...AS AREA OF LIGHT SNOW CONTINUES TO PIVOT
SLOWLY SOUTHEAST ACROSS THE REGION.
RECENT AMDAR ASCENT SOUNDING FROM KMDW CONTINUES TO DEPICT SATURATED
COLUMN FROM 900 MB THROUGH AROUND 775 MB...WITH ENTIRE MOIST LAYER
LOCATED WITHIN THE DENDRITIC GROWTH SWEET SPOT -15C TO -17C. WEAK
SHEARED MID-LEVEL VORT MAX ROTATING AROUND BACK SIDE OF LARGER SCALE
UPPER TROUGH AXIS IS PROVIDING WEAK BUT PERSISTENT FORCING
SUFFICIENT TO PRODUCE LIGHT SNOW WITH SOME MINOR ACCUMULATIONS.
TRENDS FROM SHORT TERM RAP GUIDANCE CONTINUES TO WEAKEN AND MOVE THE
VORT AXIS OFF TO THE SOUTHEAST THROUGH MID-EVENING...ALLOWING A
DECREASE IN INTENSITY OF THE LIGHT SNOW TO SCATTERED FLURRIES BY THE
LATE EVENING HOURS. THIS IS PRETTY MUCH IN LINE WITH PREVIOUS
FORECAST TRENDS...THOUGH HAVE INCREASED POPS IN NEXT FEW HOURS TO
CATEGORICAL ACROSS NORTHEAST IL WHERE LIGHT SNOW CURRENTLY PRODUCING
SOME LIGHT ACCUMS. FLUFFY NATURE OF SOME OF THE DENDRITES MAY ALLOW
UP TO A HALF INCH OF ADDITIONAL ACCUMULATION IN SOME SPOTS ACROSS
THE CHICAGO METRO AREA...COINCIDENT WITH SOME OF THE STRONG 20+ DBZ
RADAR RETURNS. DRIER AIR FILTERING IN FROM THE WEST MAY ALLOW SOME
PARTIAL CLEARING ACROSS NORTH CENTRAL IL...BEFORE RAPIDLY ADVANCING
CIRRUS SHIELD SPREADS IN AHEAD OF TOMORROWS CLIPPER.
RATZER
//PREV DISCUSSION...
301 PM CST
REST OF TODAY AND TONIGHT...
AREA OF LIGHT SNOW CONTINUES TO PIVOT ACROSS NORTHERN ILLINOIS THIS
AFTERNOON ASSOCIATED WITH A SHEARED VORT LOBE ROTATING AROUND THE
MAIN UPPER TROUGH AXIS WHICH HAS SHIFTED EAST OF THE AREA.
SMALLER SCALE FORCING IS EMBEDDED WITHIN LARGER SCALE
SUBSIDENCE AS AN H5 RIDGE BUILDS OVER THE AREA OVERNIGHT. UPSTREAM
VSBY GENERALLY IN THE 2-5SM RANGE PERIODICALLY DROPPING
BELOW...INDICATING THAT MOST OF THE SNOW IS PRETTY LIGHT. EXPECT THE
AREA TO CONTINUE TO PIVOT EAST ACROSS NORTHERN ILLINOIS POSSIBLY
DROPPING A DUSTING OF SNOW WITH FLURRIES LINGERING INTO THE
EVENING.
SATURDAY...
ANOTHER ROUND OF SNOW IS EXPECTED ON SATURDAY WITH MODEST
ACCUMULATION APPEARING LIKELY. A 130KT JET DIGGING INTO THE UPPER
MIDWEST WITH A POTENT H5 VORT MAX AT THE NOSE OF THE JET WILL RACE
SOUTHEAST ACROSS IOWA INTO CENTRAL ILLINOIS SATURDAY AFTERNOON.
TAKING A LOOK FOR THE HOOK ON THE PV1.5 SURFACE...A TROP FOLD
EXTENDS DOWN TO ALMOST 600 MB SATURDAY AFTERNOON...WITH THE BEST
PRESSURE ADVECTION AND ASCENT FOCUSED ACROSS CENTRAL ILLINOIS
INCLUDING PORTIONS OF THE FAR SOUTHERN CWA WHERE THE SURFACE LOW IS
EXPECTED TO TRACK. ISENTROPIC SURFACES SIMILARLY INDICATE TIGHTEST
PACKING IN THE FAR WEST/SOUTH CWA WITH THE BEST FOCUSED ASCENT
AND RESULTING PRECIP AXIS EXTENDING FROM ROUGHLY DIXON ILLINOIS TO
FOWLER INDIANA. IN ADDITION...CROSS SECTIONS SHOW AN AREA OF
STRONGER F-GEN TRANSLATING ALONG THAT SAME LINE WITH NEGATIVE
SATURATED EPV RIGHT ON TOP OF THE LAYER OF BEST F-GEN...INDICATING
THE POTENTIAL FOR A DEEP VERTICAL RESPONSE AND BANDED SNOWFALL WITH
UNEVEN DISTRIBUTION OF THE SNOW TOTALS. UTILIZED A NAM/GFS QPF
BLEND FOR THIS PERIOD...AND SLIGHTLY HIGHER THAN AVERAGE SNOW RATIOS
AROUND 15-16:1...CAME UP WITH 3 TO 5 INCHES ALONG AND SOUTH OF THE
DIXON TO FOWLER LINE...WITH 1 TO 3 INCHES TO THE NORTH. THESE
AMOUNTS LINE UP WELL WITH GARCIA METHOD WHICH RESULTS IN ROUGHLY 3-4
INCHES...AND SREF PLUMES. AGAIN...WITH THE POTENTIAL FOR MESOSCALE
BANDING...THERE COULD BE SOME LOCALIZED HIGHER AMOUNTS OF 5 TO 6
INCHES WITHIN THE MAIN PRECIP AXIS ACROSS THE WEST/SOUTH PORTION OF
THE CWA. WILL GO AHEAD AND ISSUE A WINTER WEATHER ADVISORY FOR 3 TO
5 INCHES OF SNOW FOR THE AFFECTED AREAS.
SUNDAY AND MONDAY...
ON SUNDAY BROAD H5 HEIGHT RISES WILL BUILD ACROSS THE AREA WITH
TRANSIENT SURFACE RIDGE PROGRESSING ACROSS THE AREA EARLY IN THE
DAY. WINDS BACK TO THE SOUTHWEST BY SUNDAY AFTERNOON WITH H85
THERMAL GRADIENT LIFTING ACROSS THE AREA...WITH TEMPS APPROACHING
3-4C. SURFACE TEMPS SHOULD PUSH TO OR SLIGHTLY ABOVE THE FREEZING
MARK...TEMPERED SOME BY SATURDAYS SNOWPACK. ANOTHER SHORTWAVE WILL
BRUSH JUST NORTH OF THE AREA SUNDAY NIGHT WITH A COLD FRONT PUSHING
SOUTH ACROSS THE AREA THROUGH THE DAY MONDAY. MOISTURE SOMEWHAT
SHALLOW BEHIND THE FRONT...BUT STEEP LOW LEVEL LAPSE RATES WITH EVEN
SOME UPRIGHT INSTABILITY NOTED ON THE SOUNDINGS INDICATE THE
POTENTIAL FOR AT LEAST SOME FLURRIES IF NOT A FEW SNOW SHOWERS.
DEPENDING ON THE EXACT TIMING OF THE FRONT...COULD SEE TEMPS FALLING
THROUGH THE DAY MONDAY. TAKING A STEP BACK AND LOOKING AT THE BIGGER
PICTURE FOR MONDAY...STRONG RIDGING OVER THE WEST COAST AND ALASKA
THIS WEEKEND WILL HELP DISLODGE AN ARCTIC AIRMASS WHICH WILL SINK
INTO GREAT LAKES MONDAY WITH THE LEADING EDGE REACHING NEAR THE OHIO
VALLEY BY MONDAY EVENING. THE COLDEST AIR AROUND -30C WILL STAY
PRIMARILY OVER THE NORTHERN LAKES REGION BUT MODELS CONTINUE TO SHOW
-20C AIR REACHING INTO ILLINOIS RESULTING IN ANOTHER PERIOD OF
FRIGID CONDITIONS AS WE HEAD INTO NEXT WEEK.
DEUBELBEISS
LONG TERM...MONDAY NIGHT THROUGH THURSDAY...
THE UPPER LEVEL TROUGH REMAINS OVERHEAD WITH SUBSEQUENT TROUGH
AXES PASS OVER THE REGION MONDAY NIGHT AND MID TO LATE NEXT WEEK.
AT THE SURFACE...HIGH PRESSURE BUILDS OVER THE GREAT PLAINS AND
MIDWEST MONDAY NIGHT THROUGH TUESDAY NIGHT. LOW PRESSURE PASSES TO
THE NORTH MID WEEK WITH HIGH PRESSURE BUILDING IN BEHIND IT.
GIVEN THE MODEL DISCREPANCIES REGARDING WHEN THE UPPER LEVEL TROUGH
AXIS/SURFACE LOW WILL PASS THROUGH THE REGION...KEPT POPS IN THE
SLIGHT CHANCE TO CHANCE RANGE MID TO LATE NEXT WEEK. THE ECMWF IS
FASTER AND FEATURES A MUCH STRONGER LOW...BUT WILL RESIST LEANING
TOO MUCH IN ITS DIRECTION.
FOR TEMPS...COLD AIR MOVES IN MONDAY NIGHT WITH 925MB TEMPS FALLING
TO -16 TO -22C. LOWERED MONDAY NIGHT/S LOWS A BIT...BUT ONCE AGAIN
WAITING FOR MODELS TO COME INTO BETTER ALIGNMENT BEFORE MAKING MAJOR
CHANGES. TUESDAY NIGHT LOOKS TO BE THE COLDEST WITH CONTINUED COLD
AIR UPSTAIRS AND A SURFACE HIGH OVERHEAD. LOWS BTWN 0 AND -10F IF
NOT COLDER ARE EXPECTED. BRIEF WAA ON WEDNESDAY WILL LEAD TO HIGH
TEMPS ABOVE 0. TEMPS AROUND ZERO ARE EXPECTED AGAIN WEDNESDAY NIGHT
WITH BELOW NORMAL TEMPS CONTINUING THROUGH LATE NEXT WEEK.
JEE
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 09Z...
* MVFR CIGS RETURN ARND 15-17Z...AND CONTINUE TO LOWER TO CIGS
ARND 1200FT AGL ARND 18Z.
* LIGHT SNOW/FLURRIES BEGIN ARND 17Z...WITH MODERATE SNOW ARRIVING
CLOSER TO 18-19Z AND LINGERING THRU 20-21Z BEFORE TURNING BACK
TO FLURRIES. PERIOD OF IFR WITH MODERATE SNOWFALL.
* LIGHT WEST WINDS ARND 10KT OVERNIGHT...TURNING SOUTH TO
SOUTHEAST MIDDAY 110-130 DEG. THEN WINDS FLIP TO NORTHWEST
290-310 DEG ARND 23-00Z.
BEACHLER
//DISCUSSION...UPDATED 06Z...
IR IMAGERY EARLY THIS MORNING SHOWS A WEDGE OF SOME CLEARING THAT
HAS TAKEN PLACE BETWEEN THE TWO WEATHER SYSTEMS...AS A RESULT OF
SOME WEAK SURFACE RIDGING. SFC OBS INDICATE WINDS HAVE BEGUN TO
DIMINISH TO ARND 7-9KT FROM THE WEST...HOWEVER JUST WEST OF
NORTHERN IL AIRFIELDS WINDS HAVE BECOME VARIABLE OR BEGINNING TO
TURN SOUTHWESTERLY. MID/UPR LEVEL CLOUDS ARE BEGINNING TO ADVANCE
SOUTHEAST AHEAD OF THE NEXT POTENT CLIPPER...WITH BASES BACK TO
5-6KFT AGL ACROSS FAR NORTHWEST IL. GUIDANCE INDICATES THIS WILL
CONTINUE TO PROGRESSIVELY OVERSPREAD NORTHERN IL/NORTHWEST IN
AIRFIELDS BY DAYBREAK.
GUIDANCE HAS BEEN TRENDING EARLIER WITH THE SNOWFALL THAN
PREVIOUSLY THOUGHT...SO HAVE ADJUSTED THE TIMING OF THE TEMPO AND
SNOW ARRIVAL TO REFLECT THIS. IT APPEARS THE LIGHT SNOW WILL BEGIN
AS FLURRIES/SNOW SHOWERS ARND 17Z. THEN THE BETTER MORE STEADY
SNOWFALL WILL ARRIVE AT ORD/MDW CLOSER TO 18-19Z. AT TIMES THE
SNOW MAY BRING VSBYS DOWN TO ARND 1SM WITH CIGS PUSHING LOWER TO
900FT AGL THROUGH THIS PERIOD OF MODERATE SNOW. THEN ON THE BACK
SIDE OF THE CLIPPER CIGS WILL BE SLOW TO IMPROVE...DESPITE
MOISTURE PEELING SOUTHEAST OF THE AIRFIELDS. SO HAVE HELD ONTO
LOWER CIGS LONGER THRU THE END TIME OF THE CURRENT TAF. WITH THE
CLIPPER WINDS WILL TURN SOUTHERLY TO POSSIBLY SOUTHEASTERLY
MIDDAY...THEN AS THE SYSTEM QUICKLY SLIDES SOUTHEAST OF THE
AIRFIELDS WINDS WILL THEN QUICKLY FLIP TO NORTHWEST. SPEEDS WILL
GENERALLY REMAIN ARND 10KT THROUGHOUT THE PERIOD AS WELL.
BEACHLER
//ORD AND MDW CONFIDENCE...UPDATED 09Z...
* HIGH CONFIDENCE IN WIND DIR/SPEED FORECAST.
* HIGH CONFIDENCE IN SNOW AND MEDIUM/HIGH CONFIDENCE IN TIMING OF
SNOW ARRIVAL/END.
* MEDIUM/HIGH CONFIDENCE IN CIGS FORECAST...WITH MEDIUM CONFIDENCE
CIGS DIP TO IFR CONDS DURING MODERATE SNOWFALL TIMING.
BEACHLER
//OUTLOOK FOR ORD/MDW FOR 12Z SUNDAY-12Z FRIDAY...UPDATED 00Z...
SUNDAY...MVFR POSSIBLE...MAINLY SUNDAY NIGHT. GUSTY SW WINDS.
MONDAY...SLGT CHC OF SNOW SHOWERS.
TUESDAY...MAINLY VFR.
WEDNESDAY-THURSDAY...SLGT CHC OF SNOW SHOWERS AND MVFR.
MTF
&&
.MARINE...
305 AM CST
FAST MOVING CLIPPER SYSTEM...HAS PUSHED SOUTHEAST FROM CENTRAL
CANADA INTO THE NORTHERN PLAINS EARLY THIS MORNING. DOWNSTREAM OF
THIS SYSTEM ACROSS LAKE MICHIGAN HAS BEEN A WEAK SURFACE
RIDGE...WHICH HAS DIMINISHED WINDS TO 10-15KT EARLY THIS MORNING.
THIS WEAK RIDGE OF HIGH PRESSURE WILL QUICKLY SHIFT EAST AHEAD OF
THE LOW PRESSURE...AND ALLOW WINDS TO TURN SOUTHERLY ACROSS THE
CENTRAL/SOUTHERN PORTIONS OF THE LAKE. AS THE LOW ARRIVES FROM THE
NORTHWEST...GUIDANCE CONTINUES TO INDICATE A TIGHTENING GRADIENT.
THIS WILL BE REFLECTED IN WINDS QUICKLY INCREASING TO 20-25KT THIS
EVENING...THEN FURTHER INCREASING TO WEST GALES TO 35 KT FOR THE
NORTHERN HALF OF THE LAKE LATE TONIGHT. THE GRADIENT WILL
EVENTUALLY WORK SOUTH ACROSS THE SOUTHERN PORTIONS OF THE LAKE AND
INCLUDE THE NORTHWEST INDIANA NEARSHORE WATERS WITH GALES TO 35 KT
DEVELOPING EARLY SUNDAY MORNING. GALE CONDITIONS WILL LIKELY
PERSIST THROUGH SUNDAY AFTERNOON...THEN DIMINISH WITH THE PASSAGE
OF A FRONTAL BOUNDARY AND SHIFT TO THE NORTHWEST LATE SUNDAY
NIGHT. WAVES WILL LIKELY REMAIN HAZARDOUS FOR THE INDIANA
NEARSHORE WATERS THROUGH SUNDAY NIGHT...POSSIBLY INTO MONDAY
MORNING.
THEN ANOTHER AREA OF LOW PRESSURE SLIDES SOUTHEAST ACROSS THE LAKE
MONDAY INTO TUESDAY. A BROAD RIDGE OF HIGH PRESSURE SLIDES SOUTH
INTO THE NORTHERN PLAINS TUESDAY...WHICH INTRODUCES ANOTHER TIGHT
PRESSURE GRADIENT AND POSSIBLY PUSH WINDS TO 30KT TUESDAY AFTERNOON
THROUGH TUESDAY NIGHT. THIS WILL ALLOW WAVES TO BUILD FOR THE
SOUTHERN HALF OF LAKE MICHIGAN TUE.
BEACHLER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...WINTER WEATHER ADVISORY...ILZ008-ILZ010-ILZ011-ILZ019 UNTIL 6 PM
SATURDAY.
WINTER WEATHER ADVISORY...ILZ020-ILZ021-ILZ022-ILZ032...10 AM
SATURDAY TO 6 PM SATURDAY.
WINTER WEATHER ADVISORY...ILZ023-ILZ033-ILZ039...10 AM SATURDAY
TO 9 PM SATURDAY.
IN...WINTER WEATHER ADVISORY...INZ010-INZ011-INZ019...10 AM SATURDAY
TO 9 PM SATURDAY.
LM...GALE WARNING...LMZ080-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...6 AM SUNDAY TO 3 PM
SUNDAY.
GALE WARNING...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-LMZ567-
LMZ868...MIDNIGHT SUNDAY TO 3 PM SUNDAY.
SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742...3 AM SUNDAY TO 10
PM SUNDAY.
GALE WARNING...LMZ743-LMZ744-LMZ745...9 AM SUNDAY TO 4 PM SUNDAY.
SMALL CRAFT ADVISORY...LMZ743-LMZ744-LMZ745...3 AM SUNDAY TO 9
AM SUNDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1155 PM CST FRI JAN 17 2014
.DISCUSSION...
640 PM CST
EARLY EVENING UPDATE...
MINOR CHANGES TO FORECAST GRIDS/ZFP TO RAISE POPS ACROSS NORTHEAST
IL THROUGH EARLY EVENING...AS AREA OF LIGHT SNOW CONTINUES TO PIVOT
SLOWLY SOUTHEAST ACROSS THE REGION.
RECENT AMDAR ASCENT SOUNDING FROM KMDW CONTINUES TO DEPICT SATURATED
COLUMN FROM 900 MB THROUGH AROUND 775 MB...WITH ENTIRE MOIST LAYER
LOCATED WITHIN THE DENDRITIC GROWTH SWEET SPOT -15C TO -17C. WEAK
SHEARED MID-LEVEL VORT MAX ROTATING AROUND BACK SIDE OF LARGER SCALE
UPPER TROUGH AXIS IS PROVIDING WEAK BUT PERSISTENT FORCING
SUFFICIENT TO PRODUCE LIGHT SNOW WITH SOME MINOR ACCUMULATIONS.
TRENDS FROM SHORT TERM RAP GUIDANCE CONTINUES TO WEAKEN AND MOVE THE
VORT AXIS OFF TO THE SOUTHEAST THROUGH MID-EVENING...ALLOWING A
DECREASE IN INTENSITY OF THE LIGHT SNOW TO SCATTERED FLURRIES BY THE
LATE EVENING HOURS. THIS IS PRETTY MUCH IN LINE WITH PREVIOUS
FORECAST TRENDS...THOUGH HAVE INCREASED POPS IN NEXT FEW HOURS TO
CATEGORICAL ACROSS NORTHEAST IL WHERE LIGHT SNOW CURRENTLY PRODUCING
SOME LIGHT ACCUMS. FLUFFY NATURE OF SOME OF THE DENDRITES MAY ALLOW
UP TO A HALF INCH OF ADDITIONAL ACCUMULATION IN SOME SPOTS ACROSS
THE CHICAGO METRO AREA...COINCIDENT WITH SOME OF THE STRONG 20+ DBZ
RADAR RETURNS. DRIER AIR FILTERING IN FROM THE WEST MAY ALLOW SOME
PARTIAL CLEARING ACROSS NORTH CENTRAL IL...BEFORE RAPIDLY ADVANCING
CIRRUS SHIELD SPREADS IN AHEAD OF TOMORROWS CLIPPER.
RATZER
//PREV DISCUSSION...
301 PM CST
REST OF TODAY AND TONIGHT...
AREA OF LIGHT SNOW CONTINUES TO PIVOT ACROSS NORTHERN ILLINOIS THIS
AFTERNOON ASSOCIATED WITH A SHEARED VORT LOBE ROTATING AROUND THE
MAIN UPPER TROUGH AXIS WHICH HAS SHIFTED EAST OF THE AREA.
SMALLER SCALE FORCING IS EMBEDDED WITHIN LARGER SCALE
SUBSIDENCE AS AN H5 RIDGE BUILDS OVER THE AREA OVERNIGHT. UPSTREAM
VSBY GENERALLY IN THE 2-5SM RANGE PERIODICALLY DROPPING
BELOW...INDICATING THAT MOST OF THE SNOW IS PRETTY LIGHT. EXPECT THE
AREA TO CONTINUE TO PIVOT EAST ACROSS NORTHERN ILLINOIS POSSIBLY
DROPPING A DUSTING OF SNOW WITH FLURRIES LINGERING INTO THE
EVENING.
SATURDAY...
ANOTHER ROUND OF SNOW IS EXPECTED ON SATURDAY WITH MODEST
ACCUMULATION APPEARING LIKELY. A 130KT JET DIGGING INTO THE UPPER
MIDWEST WITH A POTENT H5 VORT MAX AT THE NOSE OF THE JET WILL RACE
SOUTHEAST ACROSS IOWA INTO CENTRAL ILLINOIS SATURDAY AFTERNOON.
TAKING A LOOK FOR THE HOOK ON THE PV1.5 SURFACE...A TROP FOLD
EXTENDS DOWN TO ALMOST 600 MB SATURDAY AFTERNOON...WITH THE BEST
PRESSURE ADVECTION AND ASCENT FOCUSED ACROSS CENTRAL ILLINOIS
INCLUDING PORTIONS OF THE FAR SOUTHERN CWA WHERE THE SURFACE LOW IS
EXPECTED TO TRACK. ISENTROPIC SURFACES SIMILARLY INDICATE TIGHTEST
PACKING IN THE FAR WEST/SOUTH CWA WITH THE BEST FOCUSED ASCENT
AND RESULTING PRECIP AXIS EXTENDING FROM ROUGHLY DIXON ILLINOIS TO
FOWLER INDIANA. IN ADDITION...CROSS SECTIONS SHOW AN AREA OF
STRONGER F-GEN TRANSLATING ALONG THAT SAME LINE WITH NEGATIVE
SATURATED EPV RIGHT ON TOP OF THE LAYER OF BEST F-GEN...INDICATING
THE POTENTIAL FOR A DEEP VERTICAL RESPONSE AND BANDED SNOWFALL WITH
UNEVEN DISTRIBUTION OF THE SNOW TOTALS. UTILIZED A NAM/GFS QPF
BLEND FOR THIS PERIOD...AND SLIGHTLY HIGHER THAN AVERAGE SNOW RATIOS
AROUND 15-16:1...CAME UP WITH 3 TO 5 INCHES ALONG AND SOUTH OF THE
DIXON TO FOWLER LINE...WITH 1 TO 3 INCHES TO THE NORTH. THESE
AMOUNTS LINE UP WELL WITH GARCIA METHOD WHICH RESULTS IN ROUGHLY 3-4
INCHES...AND SREF PLUMES. AGAIN...WITH THE POTENTIAL FOR MESOSCALE
BANDING...THERE COULD BE SOME LOCALIZED HIGHER AMOUNTS OF 5 TO 6
INCHES WITHIN THE MAIN PRECIP AXIS ACROSS THE WEST/SOUTH PORTION OF
THE CWA. WILL GO AHEAD AND ISSUE A WINTER WEATHER ADVISORY FOR 3 TO
5 INCHES OF SNOW FOR THE AFFECTED AREAS.
SUNDAY AND MONDAY...
ON SUNDAY BROAD H5 HEIGHT RISES WILL BUILD ACROSS THE AREA WITH
TRANSIENT SURFACE RIDGE PROGRESSING ACROSS THE AREA EARLY IN THE
DAY. WINDS BACK TO THE SOUTHWEST BY SUNDAY AFTERNOON WITH H85
THERMAL GRADIENT LIFTING ACROSS THE AREA...WITH TEMPS APPROACHING
3-4C. SURFACE TEMPS SHOULD PUSH TO OR SLIGHTLY ABOVE THE FREEZING
MARK...TEMPERED SOME BY SATURDAYS SNOWPACK. ANOTHER SHORTWAVE WILL
BRUSH JUST NORTH OF THE AREA SUNDAY NIGHT WITH A COLD FRONT PUSHING
SOUTH ACROSS THE AREA THROUGH THE DAY MONDAY. MOISTURE SOMEWHAT
SHALLOW BEHIND THE FRONT...BUT STEEP LOW LEVEL LAPSE RATES WITH EVEN
SOME UPRIGHT INSTABILITY NOTED ON THE SOUNDINGS INDICATE THE
POTENTIAL FOR AT LEAST SOME FLURRIES IF NOT A FEW SNOW SHOWERS.
DEPENDING ON THE EXACT TIMING OF THE FRONT...COULD SEE TEMPS FALLING
THROUGH THE DAY MONDAY. TAKING A STEP BACK AND LOOKING AT THE BIGGER
PICTURE FOR MONDAY...STRONG RIDGING OVER THE WEST COAST AND ALASKA
THIS WEEKEND WILL HELP DISLODGE AN ARCTIC AIRMASS WHICH WILL SINK
INTO GREAT LAKES MONDAY WITH THE LEADING EDGE REACHING NEAR THE OHIO
VALLEY BY MONDAY EVENING. THE COLDEST AIR AROUND -30C WILL STAY
PRIMARILY OVER THE NORTHERN LAKES REGION BUT MODELS CONTINUE TO SHOW
-20C AIR REACHING INTO ILLINOIS RESULTING IN ANOTHER PERIOD OF
FRIGID CONDITIONS AS WE HEAD INTO NEXT WEEK.
DEUBELBEISS
LONG TERM...MONDAY NIGHT THROUGH THURSDAY...
THE UPPER LEVEL TROUGH REMAINS OVERHEAD WITH SUBSEQUENT TROUGH
AXES PASS OVER THE REGION MONDAY NIGHT AND MID TO LATE NEXT WEEK.
AT THE SURFACE...HIGH PRESSURE BUILDS OVER THE GREAT PLAINS AND
MIDWEST MONDAY NIGHT THROUGH TUESDAY NIGHT. LOW PRESSURE PASSES TO
THE NORTH MID WEEK WITH HIGH PRESSURE BUILDING IN BEHIND IT.
GIVEN THE MODEL DISCREPANCIES REGARDING WHEN THE UPPER LEVEL TROUGH
AXIS/SURFACE LOW WILL PASS THROUGH THE REGION...KEPT POPS IN THE
SLIGHT CHANCE TO CHANCE RANGE MID TO LATE NEXT WEEK. THE ECMWF IS
FASTER AND FEATURES A MUCH STRONGER LOW...BUT WILL RESIST LEANING
TOO MUCH IN ITS DIRECTION.
FOR TEMPS...COLD AIR MOVES IN MONDAY NIGHT WITH 925MB TEMPS FALLING
TO -16 TO -22C. LOWERED MONDAY NIGHT/S LOWS A BIT...BUT ONCE AGAIN
WAITING FOR MODELS TO COME INTO BETTER ALIGNMENT BEFORE MAKING MAJOR
CHANGES. TUESDAY NIGHT LOOKS TO BE THE COLDEST WITH CONTINUED COLD
AIR UPSTAIRS AND A SURFACE HIGH OVERHEAD. LOWS BTWN 0 AND -10F IF
NOT COLDER ARE EXPECTED. BRIEF WAA ON WEDNESDAY WILL LEAD TO HIGH
TEMPS ABOVE 0. TEMPS AROUND ZERO ARE EXPECTED AGAIN WEDNESDAY NIGHT
WITH BELOW NORMAL TEMPS CONTINUING THROUGH LATE NEXT WEEK.
JEE
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* MVFR CIGS RETURN ARND 15-17Z...AND CONTINUE TO LOWER TO CIGS
ARND 1200FT AGL ARND 18Z.
* LIGHT SNOW/FLURRIES BEGIN ARND 17Z...WITH MODERATE SNOW ARRIVING
CLOSER TO 18-19Z AND LINGERING THRU 20-21Z BEFORE TURNING BACK
TO FLURRIES. PERIOD OF IFR WITH MODERATE SNOWFALL.
* LIGHT WEST WINDS ARND 10KT OVERNIGHT...TURNING SOUTH TO
SOUTHEAST MIDDAY 110-130 DEG. THEN WINDS FLIP TO NORTHWEST
290-310 DEG ARND 23-00Z.
BEACHLER
//DISCUSSION...UPDATED 06Z...
IR IMAGERY EARLY THIS MORNING SHOWS A WEDGE OF SOME CLEARING THAT
HAS TAKEN PLACE BETWEEN THE TWO WEATHER SYSTEMS...AS A RESULT OF
SOME WEAK SURFACE RIDGING. SFC OBS INDICATE WINDS HAVE BEGUN TO
DIMINISH TO ARND 7-9KT FROM THE WEST...HOWEVER JUST WEST OF
NORTHERN IL AIRFIELDS WINDS HAVE BECOME VARIABLE OR BEGINNING TO
TURN SOUTHWESTERLY. MID/UPR LEVEL CLOUDS ARE BEGINNING TO ADVANCE
SOUTHEAST AHEAD OF THE NEXT POTENT CLIPPER...WITH BASES BACK TO
5-6KFT AGL ACROSS FAR NORTHWEST IL. GUIDANCE INDICATES THIS WILL
CONTINUE TO PROGRESSIVELY OVERSPREAD NORTHERN IL/NORTHWEST IN
AIRFIELDS BY DAYBREAK.
GUIDANCE HAS BEEN TRENDING EARLIER WITH THE SNOWFALL THAN
PREVIOUSLY THOUGHT...SO HAVE ADJUSTED THE TIMING OF THE TEMPO AND
SNOW ARRIVAL TO REFLECT THIS. IT APPEARS THE LIGHT SNOW WILL BEGIN
AS FLURRIES/SNOW SHOWERS ARND 17Z. THEN THE BETTER MORE STEADY
SNOWFALL WILL ARRIVE AT ORD/MDW CLOSER TO 18-19Z. AT TIMES THE
SNOW MAY BRING VSBYS DOWN TO ARND 1SM WITH CIGS PUSHING LOWER TO
900FT AGL THROUGH THIS PERIOD OF MODERATE SNOW. THEN ON THE BACK
SIDE OF THE CLIPPER CIGS WILL BE SLOW TO IMPROVE...DESPITE
MOISTURE PEELING SOUTHEAST OF THE AIRFIELDS. SO HAVE HELD ONTO
LOWER CIGS LONGER THRU THE END TIME OF THE CURRENT TAF. WITH THE
CLIPPER WINDS WILL TURN SOUTHERLY TO POSSIBLY SOUTHEASTERLY
MIDDAY...THEN AS THE SYSTEM QUICKLY SLIDES SOUTHEAST OF THE
AIRFIELDS WINDS WILL THEN QUICKLY FLIP TO NORTHWEST. SPEEDS WILL
GENERALLY REMAIN ARND 10KT THROUGHOUT THE PERIOD AS WELL.
BEACHLER
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* HIGH CONFIDENCE IN WIND DIR/SPEED FORECAST.
* HIGH CONFIDENCE IN SNOW AND MEDIUM/HIGH CONFIDENCE IN TIMING OF
SNOW ARRIVAL/END.
* MEDIUM/HIGH CONFIDENCE IN CIGS FORECAST...WITH MEDIUM CONFIDENCE
CIGS DIP TO IFR CONDS DURING MODERATE SNOWFALL TIMING.
BEACHLER
//OUTLOOK FOR ORD/MDW FOR 12Z SUNDAY-12Z FRIDAY...UPDATED 00Z...
SUNDAY...MVFR POSSIBLE...MAINLY SUNDAY NIGHT. GUSTY SW WINDS.
MONDAY...SLGT CHC OF SNOW SHOWERS.
TUESDAY...MAINLY VFR.
WEDNESDAY-THURSDAY...SLGT CHC OF SNOW SHOWERS AND MVFR.
MTF
&&
.MARINE...
300 PM...
A SERIES OF CLIPPER-TYPE SYSTEMS WILL TRACK THROUGH THE GREAT
LAKES REGION OVER THE NEXT SEVERAL DAYS. THIS WILL BRING PERIODS
OF INCREASING AND DECREASING WINDS OF VARIABLE DIRECTION TO THE
LAKE. THE FIRST SYSTEM...OVER LAKE HURON...WILL CONTINUE TO
WEAKEN AS IT MOVES INTO QUEBEC LATE TONIGHT WHILE DRAGGING A WEAK
COLD FRONT SOUTH DOWN THE LAKE TURNING WINDS FROM WESTERLY TO
NORTHWESTERLY. THE NEXT SYSTEM WILL DROP OUT OF NORTHERN ALBERTA
LATE TONIGHT AND DEEPEN AS IT MOVES THROUGH MINNESOTA SATURDAY
MORNING. THIS LOW WILL SLOWLY WEAKEN AS IT TRACKS THROUGH CENTRAL
ILLINOIS SATURDAY AFTERNOON AND DISSIPATE AS IT REACHES THE UPPER
OHIO VALLEY SUNDAY. THIS WILL BE A PERIOD OF RELATIVELY LIGHTER
WINDS OVER THE LAKE...BUT ANOTHER...STRONGER...LOW IS EXPECTED TO
DEVELOP OVER NORTHERN MANITOBA FRIDAY NIGHT AND DROP SOUTHEAST
ACROSS ONTARIO SATURDAY NIGHT WHILE DEEPENING. STRENGTHENING WINDS
AHEAD OF AN ASSOCIATED COLD FRONT MAY APPROACH OR REACH GALE FORCE
SATURDAY NIGHT OR SUNDAY. HIGH PRESSURE WILL THEN BUILD IN BEHIND
THIS FRONT ALLOWING WINDS TO WEAKEN SOMEWHAT AGAIN. THIS PATTERN
SHOULD REPEAT AGAIN EARLY NEXT WEEK AS ANOTHER CLIPPER DROPS OUT
OF CANADA AND TRACKS THROUGH THE UPPER GREAT LAKES,
KREIN
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...WINTER WEATHER ADVISORY...ILZ010-ILZ019-ILZ021-ILZ032...6 AM
SATURDAY TO 6 PM SATURDAY.
WINTER WEATHER ADVISORY...ILZ023-ILZ033-ILZ039...10 AM SATURDAY
TO 9 PM SATURDAY.
IN...WINTER WEATHER ADVISORY...INZ019...10 AM SATURDAY TO 9 PM
SATURDAY.
LM...SMALL CRAFT ADVISORY...INDIANA NEARSHORE WATERS UNTIL 6 AM SATURDAY.
&&
$$
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 GOODLAND KS
235 AM MST SAT JAN 18 2014
.SHORT TERM...(TODAY THROUGH MONDAY NIGHT)
ISSUED AT 230 AM MST SAT JAN 18 2014
TODAY-TONIGHT...STRONG VORT MAX CURRENTLY MOVING TOWARD NORTHERN
IOWA AND NOSE OF 120KT UPPER JET WILL BOTH SLIDE SOUTH/SOUTHEAST
TODAY THEN ACROSS THE EAST COAST TONIGHT. STRONGEST WINDS ALOFT MOVE
INTO THE AREA THIS MORNING AND CONTINUE THROUGH LATE MORNING/EARLY
AFTERNOON BEFORE SLOWLY DECREASING LATE THIS AFTERNOON THROUGH
SUNSET. LOCAL WIND GUST PROGRAM SUGGESTING GUSTS OF 45 TO 57 KTS
ACROSS THE AREA AT 18Z (STRONGEST AT KGLD AND KITR) WITH 40 TO 46
KTS BY 21Z. SO THE QUESTION BECOMES WILL A HIGH WIND WARNING BE
NEEDED.
MET/MAV GUIDANCE ALL SHOWING SUSTAINED WINDS AROUND 30KTS VERY LATE
THIS MORNING WITH A DECREASING TREND THIS AFTERNOON. 06Z RUC SHOWING
GUSTS 50-52KTS FROM COLBY EAST AROUND 18Z WHICH IS OPPOSITE OF WIND
GUST PROGRAM RESULTS. SEEMS TO BE A LACK OF REALLY FAVORABLE OR EVEN
FAVORABLE LOW AND MID LEVEL LAPSE RATES WHICH IS KEEPING ME FROM
UPGRADING TO A HIGH WIND WARNING. EITHER WAY...IT WILL BE WINDY WITH
GUSTS OVER 50 MPH POSSIBLE ALONG WITH SOME BLOWING DUST FROM TIME
TO TIME.
HIGH TEMPERATURES UPPER 40S NORTHEAST WITH LOW 50S ELSEWHERE. LOWS
TONIGHT IN THE 20S.
SUNDAY-SUNDAY NIGHT...WEATHER STORY FOR THIS PERIOD WILL BE MUCH
ABOVE NORMAL HIGH TEMPERATURES WITH 850 TEMPERATURES AND NEARLY ALL
REMAINING GUIDANCE SUPPORTING UPPER 50S TO MID 60S ACROSS THE AREA.
A FEW LOCATIONS SUCH AS MCCOOK AND HILL CITY WILL BE CLOSE IF NOT
REACH RECORD HIGHS FOR THE DAY. SEE CLIMATE SECTION BELOW. LOWS
IN THE LOW TO MID 20S.
MONDAY-MONDAY NIGHT...COLDER TEMPERATURES RETURN AS 850 TEMPERATURES
DROP ABOUT 15-20F FROM SUNDAYS READINGS PUTTING THE AREA BACK INTO
THE 40S FOR HIGHS...CLOSER TO NORMAL FOR MID JANUARY. LOWS MONDAY
NIGHT BELOW NORMAL IN THE SINGLE DIGITS TO MID TEENS AS HIGH
PRESSURE MOVES IN. LOOKS LIKE ANOTHER BREEZY TO WINDY DAY AND HAVE
INCREASED WINDS A BIT AS A RESULT.
NO PRECIPITATION IS EXPECTED THROUGH THE PERIOD.
.LONG TERM...(TUESDAY THROUGH FRIDAY)
ISSUED AT 230 AM MST SAT JAN 18 2014
A STUBBORN TROUGH/RIDGE PATTERN ACROSS THE CONUS CONTINUES THROUGH
NEXT WEEK. THE RIDGE OVER THE WEST COAST LOOKS TO AMPLIFY TOWARDS
THE END OF THE WEEK WITH H5 HEIGHTS OVER 2 STANDARD DEVIATIONS ABOVE
NORMAL ACROSS THE WESTERN COAST OF CANADA. LOCALLY NORTHWEST FLOW
WILL PERSIST AT UPPER LEVELS WITH A FEW FRONTS OVER THE COURSE OF
THE WEEK. EXTENDED PERIOD WILL BE GENERALLY DRY WITH NEAR SEASONABLE
TEMPS.
TUE AND WED WILL BE MOSTLY SUNNY AND SEASONABLE WITH LIGHT
NORTHWEST WINDS. LATE WEDNESDAY CLOUDS WILL INCREASE AHEAD OF A
BACK DOOR COLD FRONT ASSOCIATED WITH A BROAD AREA OF HIGH PRESSURE
DEVELOPING ACROSS THE NORTHERN PLAINS. COLD CANADIAN AIR WILL
ACCOMPANY THIS SYSTEM...THOUGH LUCKILY THE COLDEST AIR WILL REMAIN
MUCH FARTHER NORTH AND EAST. WHILE THERE IS SOME DISCREPANCIES AS
FAR AS THE COLD GOES...GUIDANCE IS IN FAIRLY GOOD AGREEMENT THAT
WE WILL SEE SOME MID-LEVEL MOISTURE MOVE SOUTH THROUGH THE HIGH
PLAINS AND REACH THE CWA WED NIGHT INTO EARLY THURSDAY. WHILE
LIFT/DYNAMICS ARE NOT VERY GOOD...WOULD NOT BE SURPRISED FOR SEE A
FEW FLURRIES DURING THIS TIME AS WELL...ESPECIALLY IF WE CAN GET
SOME ENHANCEMENT FROM THE RIGHT ENTRANCE REGION OF THE 250MB JET.
THURS WILL BE BREEZY AS THE HIGH PRESSURE OVER THE NORTHERN PLAINS
MOVES EAST. CLOUDS WILL DECREASE LATE IN THE DAY AS WINDS PICK UP OUT
OF THE SOUTH AT 15 TO 20 KTS DUE TO THE STRONG PRESSURE GRADIENT
ACROSS WESTERN KANSAS. FRIDAY WILL BE SEASONABLE...WITH SOME HIGH
CLOUDS LIMITING AFTERNOON TEMPS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 230 AM MST SAT JAN 18 2014
FOR KGLD AND KMCK...VFR CONDITIONS EXPECTED THROUGH THE PERIOD.
AVIATION CONCERN WILL BE HOW STRONG WINDS GET LATE THIS MORNING
THROUGH AFTERNOON AND IF BLOWING DUST CAN DEVELOP. IF
SO...RESTRICTED VISIBILITIES ARE POSSIBLE.
UPPER JET TO MOVE ACROSS THE AREA WITH PEAK WINDS VERY LATE THIS
MORNING THROUGH EARLY AFTERNOON. NORTHWEST WINDS GUSTING 40-45KTS
EXPECTED IN THE 18Z-21Z TIME FRAME WITH SLIGHTLY LOWER GUSTS 2-3
HOURS EITHER SIDE. AROUND 00Z NORTHWEST WINDS AROUND 15KTS WILL
BACK TO THE WEST THEN SOUTHWEST THROUGH 12Z AT 8-13KTS...HIGHEST
AT KGLD.
&&
.FIRE WEATHER...
ISSUED AT 230 AM MST SAT JAN 18 2014
TODAY...CURRENT RED FLAG WARNING AREAL COVERAGE LOOKS GOOD AS RH
VALUES AROUND 20 PERCENT COMBINE WITH NORTHWEST WINDS GUSTING UP
TO 50 MPH...POSSIBLY A BIT HIGHER IN SPOTS. AS FAR AS
TIMING...CURRENT START TIME MAY BE A FEW HOURS EARLY.
SUNDAY...RH VALUES FALL INTO THE 20-25 PERCENT RANGE ACROSS THE
AREA DURING THE EARLY AFTERNOON. NORTHWEST WINDS OF 15 TO 20 MPH
ARE POSSIBLE CREATING NEAR CRITICAL FIRE WEATHER CONDITIONS.
SOMETHING TO WATCH.
MONDAY...RH VALUES FALL TOWARD 25 PERCENT BY MID AFTERNOON.
NORTHWEST WINDS OF 20 TO 25 MPH WITH HIGHER GUSTS EXPECTED WHICH
WILL CREATE NEAR CRITICAL FIRE WEATHER CONDITIONS. LATER SHIFTS
WILL NEED TO RE-EVALUATE FOR POSSIBLE FIRE WEATHER HIGHLITE.
&&
.CLIMATE...
ISSUED AT 230 AM MST SAT JAN 18 2014
RECORD AND/OR NEAR RECORD HIGH TEMPERATURES ARE POSSIBLE SUNDAY
JANUARY 19 AT HILL CITY AND MCCOOK. CURRENT RECORDS FOR THE DATE
ARE:
HILL CITY...66 IN 2006 AND PREVIOUS YEARS
MCCOOK......66 IN 1997
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...RED FLAG WARNING FROM 10 AM MST /11 AM CST/ THIS MORNING TO 5 PM
MST /6 PM CST/ THIS AFTERNOON FOR KSZ001-002-013>015-
027>029-041-042.
WIND ADVISORY FROM 9 AM MST /10 AM CST/ THIS MORNING TO 5 PM MST
/6 PM CST/ THIS AFTERNOON FOR KSZ001>004-013>016-027>029-
042.
CO...RED FLAG WARNING FROM 10 AM THIS MORNING TO 5 PM MST THIS
AFTERNOON FOR COZ252>254.
WIND ADVISORY FROM 9 AM THIS MORNING TO 5 PM MST THIS AFTERNOON
FOR COZ090-091.
NE...RED FLAG WARNING FROM 10 AM THIS MORNING TO 5 PM MST THIS
AFTERNOON FOR NEZ079.
WIND ADVISORY FROM 9 AM MST /10 AM CST/ THIS MORNING TO 5 PM MST
/6 PM CST/ THIS AFTERNOON FOR NEZ079>081.
&&
$$
SHORT TERM...99
LONG TERM...JJM
AVIATION...99
FIRE WEATHER...99
CLIMATE...99
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
216 AM EST SAT JAN 18 2014
.SYNOPSIS...
A COLD FRONT WILL CROSS THE REGION TONIGHT INTO EARLY SATURDAY
MORNING. HIGH PRESSURE WILL RETURN BY SATURDAY AFTERNOON. ANOTHER
COLD FRONT WILL SWING ACROSS THE REGION ON SUNDAY. AN EXTENDED
PERIOD OF WELL BELOW NORMAL TEMPERATURES IS EXPECTED DURING THE
MIDDLE AND END OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
NO MAJOR CHANGES NEC TO THE FORECAST PACKAGE TNGT. WITH 00Z NAM
AND RAP COMING IN DRY ACROSS THE AREA SEE NO REASON TO BUMP UP
POPS HIGHER THAN 20% OVRNGT. CAN`T RULE OUT SOME
SPRINKLES/FLURRIES OVR NRN AREAS. OTHERWISE...PRTLY CLOUDY ON AVG
WITH LO TEMPS RANGING FRM THE MID/UPR 20S OVR THE PIEDMONT TO THE
MID/UPR 30S NEAR THE CST.
PREVIOUS DISCUSSION...
A COLD FRONT WILL QUICKLY APPROACH THE LOCAL AREA BY THIS
EVENING...THEN MOVES THRU TONIGHT INTO EARLY SAT MORNING. LATEST
MODEL GUIDANCE IS NOT ALL THAT ENTHUSIASTIC ABOUT THE CHANCE FOR
MEASURABLE PCPN ACROSS THE FA TONIGHT. THIS IS MOSTLY DUE TO THE
FAR NE TRACK OF THE UPPER LOW (ACROSS THE OH VALLEY/EASTERN GREAT
LAKES) AND THE FAR NORTHERN TRACK OF THE SFC LOW. THE MODELS DUE
SHOW A LITTLE ENERGY TRANSLATING TO THE COAST AND INTERACTING WITH
THE GULF STREAM BETWEEN 06Z-12Z. HOWEVER...BY THEN IT WILL BE TOO
LITTLE TOO LATE FOR OUR FA SINCE THE COLD FRONT WILL BE THRU BY
THEN AND THE BEST CHANCE FOR PCPN REMAINS OFFSHORE. WILL CARRY
MAINLY GHOST POPS OVERNIGHT (<15%) FOR THE POSSIBILITY OF ISOLATED
SPRINKLES/FLURRIES AS THE FRONT PASSES. SLIGHT CHC POPS (20%) WERE
LEFT IN THE FAR NW COUNTIES BETWEEN 03-06Z...THEN ACROSS FAR
EASTERN AREAS BETWEEN 06-12Z. AT BEST...THERE MAY BE A QUICK SNOW
SHOWER IN THESE AREAS WITH NO SNOW ACCUMULATION EXPECTED. LOWS
TONIGHT IN THE MID 20S NW TO THE MID 30S AT THE COAST.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH MONDAY/...
A BRIEF RETURN OF HIGH PRESSURE WILL OCCUR ON SATURDAY WITH
PLENTY OF SUNSHINE. TEMPS WILL BE COOLER THAN TODAY IN THE WAKE
OF THE COLD FRONT. HIGHS IN THE MID 30S TO LOW 40S WITH A DECENT
BREEZE...MAKING IT FEEL LIKE THE 20S.
NEXT POTENT SHORTWAVE (AND ASSOCIATED COLD FRONT) DIGS ACROSS THE
OH VALLEY EARLY SAT NGT...THEN SWINGS THRU THE MID ATLANTIC LATE
SAT NIGHT INTO MIDDAY SUN. THIS SYSTEM WILL ALSO HAVE LIMITED LOW
LEVEL MOISTURE TO WORK WITH...AND COMBINED WITH THE SHEERING
NATURE OF THE UPR TROUGH WILL MAKE IT HARD TO PRODUCE ANY
ACCUMULATING PCPN. WILL KEEP THE FORECAST DRY SAT NIGHT...THEN
MAINTAIN SLIGHT CHC POPS (20%) ACROSS THE EASTERN SHORE SUN
MORNING. CANNOT RULE OUT A FEW FLURRIES SUN MORNING ACROSS THE
ENTIRE CWA. BECOMING PARTLY OR MOSTLY SUNNY FROM LATE SUN MORNING
THRU SUN AFTN...AS THAT FRONT PUSHES OUT TO SEA AND HIGH PRESSURE
BUILDS IN FROM THE SW. BREEZY WITH MAX TEMPS IN THE 40S TO NR 50.
HIGH PRESSURE REMAINS IN PLACE MONDAY MORNING BEFORE A COLD FRONT
SAGS SOUTHWARD INTO THE AREA LATE MONDAY AFTERNOON. DRY WITH
HIGHS IN THE 50S TO AROUND 60.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
MODELS AGREE ON GENERAL PATTERN IN THE MEDIUM RANGE WHICH WILL BE
DOMINATED BY STRONG RIDGING ACRS WESTERN NORTH AMERICA...AND A DEEP
TROUGH OVER EASTERN CANADA AND THE GREAT LAKES. DIFFERENCES ARE
FAIRLY MINIMAL SO CONFIDENCE IS HIGH THAT WELL BELOW AVG
TEMPERATURES WILL PREVAIL DURING THE PERIOD...ESPECIALLY WED/THU.
OVERALL...CONDITIONS LOOK DRY AS ARCTIC AIRMASS OVERSPREADS THE
REGION FROM LATE TUE AND BEYOND. STILL SOME QUESTION THOUGH AS TO
POTENTIAL FOR SOME SNOW TUE/TUE NIGHT AS A POTENT UPPER LEVEL
SHORTWAVE TRACKS THROUGH THE MID ATLC/SE STATES AND DEVELOPS A SFC
LOW OFF THE NC COAST. CURRENT PATTERN DEPICTED BY LATEST
GFS/ECMWF/GLOBAL IS TOO PROGRESSIVE FOR MORE THAN A LOW CHC FOR
PRECIP SO WILL ONLY CARRY 20% POPS MOST AREAS AND 30% CHC FOR SE
VA/NE NC AT THIS TIME. HIGHS TUE AVG IN THE LOW 40S NE NC TO THE
LOW-MID 30S ACRS THE FAR NORTH...WITH LOWS WED IN THE TEENS NW TO
THE MID/UPPER 20S SE. EXPECT PARTLY CLOUDY TO VARIABLY SKIES
WED-FRI...ANOTHER WEAK SYSTEM MAY AFFECT THE REGION SOMETIME THU
ALTHOUGH MODELS DIVERGE IN TIMING THE SHORTWAVES IN THE W/NW FLOW
PATTERN BY THIS TIME. HIGHS WED LIKELY STAY IN THE UPPER 20S FROM
RICHMOND ON NORTH...WITH ONLY LOW 30S ACRS THE SOUTH. ONLY A SLIGHT
MODERATION EXPECTED THU/FRI...WITH HIGHS MAINLY IN THE 30S AND LOWS
IN THE TEENS TO LWR 20S.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
A COLD FRONT IS CROSSING THE COAST AS OF 18/0630Z THIS MORNING AND
PRECIPITATION ALONG THE FRONT CONSISTS OF LIGHT RAIN SHOWERS. THE
LOWEST CIGS SEEN WITHIN THE LOCAL OBSERVATION NETWORK ARE AROUND
4 KFT AGL. CIGS BTWN 4-5 KT FT AGL SHOULD PERSIST THROUGH THIS
MORNING BEFORE BREAKING UP/BECOMING SCATTERED THIS AFTERNOON.
THEREFORE...VFR CONDITIONS ARE EXPECTED TO PERSIST OVER THE NEXT
24 HOURS. WINDS WILL BE SW IN THE VICINITY OF THE FRONT AND THEN
VEER TO THE W-NW BEHIND ITS PASSAGE. DECENT COLD AIR ADVECTION AND
AN AMPLIFIED SFC HIGH PRESSURE RIDGE BUILDING ACROSS THE OHIO
VALLEY TODAY WILL CAUSE THE PRESSURE GRADIENT TO TIGHTEN. BREEZY
CONDITIONS WILL DEVELOP BY MID MORNING...PEAK THIS AFTERNOON...AND
THEN DIMINISH THROUGH THIS EVENING. EXPECT W-NW WINDS OF GENERALLY
10-15 KT WITH GUSTS UP TO 20 KT WEST OF INTERSTATE 95 AND SPEEDS
OF 15 TO 20 KT WITH GUSTS UP TO 25 KT EAST OF INTERSTATE 95.
ANOTHER LOW PRESSURE SYSTEM WILL MOVE ACROSS THE OHIO VALLEY TWD
NRN VA TONIGHT...PUSHING A COLD FRONT THROUGH THE AREA ON SUNDAY.
SFC MOISTURE WILL BE LACKING DUE TO RECENT COLD AIR ADVECTION AND
BREEZY WINDS...MAKING PRECIPITATION GENERATION DIFFICULT ESPECIALLY
AS THE UPPER LEVEL ENERGY SHEARS APART DURING THE FRONTAL PASSAGE.
THIS SYSTEM WILL PRIMARILY SPREAD HIGH CLOUDS BACK INTO THE REGION
FROM THE W-NW THIS EVENING. CLOUDS ARE EXPECTED TO THICKEN AND
LOWER OVERNIGHT INTO SUN MORNING WITH LIGHT SNOW FLURRIES POSSIBLE...
HOWEVER THIS SHOULD HAVE LITTLE TO NO IMPACT ON AIRFIELD OPERATIONS.
A BRIEF SURGE OF COLDER AIR BEHIND THE FRONT WILL RESULT IN BREEZY
SW-W WINDS DEVELOPING BY MID-MORNING SUNDAY AND PERSISTING THROUGH
THE AFTERNOON BEFORE SLACKENING.
&&
.MARINE...
UPDATE...
SCA FLAGS HAVE BEEN ALLOWED TO START AT 06Z EARLY THIS MORNING AND
WILL CONTINUE THROUGH THIS EVENING. A QUICK BURST OF SW WINDS AT
LOW-END SCA SPEEDS AHEAD OF THE FRONT WILL GIVE WAY TO A STRONGER
W-NW SURGE BEHIND THE FRONT AS THE PRESSURE GRADIENT TIGHTENS AND
COLD AIR ADVECTION PROCESSES TAKE OVER. EXPECT WIND SPEEDS AROUND
20-25 KT FOR BAY/COASTAL WATERS AND AVERAGE SPEEDS OF 15-20 KT
CURRITUCK SOUND/ERN VA RIVERS. SEAS AVERAGING 2-3 FT SHOULD
QUICKLY BUILD TO 4-5 FT ONCE THE W-NW SURGE BEGINS. CHES BAY
SHOULD ALSO EXPERIENCE RAPIDLY BUILDING WAVES FROM 1-2 FT TO 3-4
FT. ALTHOUGH THERE MAY BE A LAG IN WIND SPEEDS OVER SRN COASTAL
WATERS SOUTH OF CAPE CHARLES...SEAS ARE EXPECTED TO REACH 5 FT
NEAR 20 NM DURING THE FRONTAL PASSAGE. SEAS IN THIS AREA WILL STAY
AROUND 4-5 FT THROUGH TODAY AND SHOULD BEGIN TO SUBSIDE THIS
EVENING...HOWEVER SEAS MAY LINGER AROUND 5 FT NEAR 20 NM INTO LATE
EVENING. HAVE ADDED SRN WATERS INTO SCA HEADLINES FROM CAPE
CHARLES TO CURRITUCK LIGHT BEGINNING IMMEDIATELY AND PERSISTING
UNTIL MIDNIGHT TONIGHT TO ACCOUNT FOR THE POSSIBILITY OF SLOWLY
SUBSIDING SEAS.
PREVIOUS DISCUSSION...
SCA CONDITIONS MAY RE-DEVELOP SUN AND SUN NIGHT. SCA HEADLINES MAY
NEED TO BE EXTENDED THROUGH SAT NIGHT DUE TO A LULL ANTICIPATED TO
LAST LESS THAN 12 HOURS. BENIGN CONDITIONS ARE INDICATED FOR MON AND
TUE. ANOTHER ROUND OF HEADLINES MAY BE NEEDED LATER IN THE WEEK AS
MORE COLD AIR POURS INTO THE REGION.
&&
.EQUIPMENT...
THE NOAA ALL HAZARD WEATHER RADIO (KHB-57) EMANATING FROM DRIVER,
VA ON A FREQUENCY OF 162.550 MHZ WILL BE OFF THE AIR UNTIL
FURTHER NOTICE DUE TO ANTENNA PROBLEMS. RETURN TO NORMAL SERVICE
IS NOT KNOWN AT THIS TIME.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 PM EST THIS EVENING FOR
ANZ630>632-634>638.
SMALL CRAFT ADVISORY FROM 7 AM THIS MORNING TO 7 PM EST THIS
EVENING FOR ANZ633.
SMALL CRAFT ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR ANZ650-652-
654.
SMALL CRAFT ADVISORY FROM 7 AM THIS MORNING TO MIDNIGHT EST
TONIGHT FOR ANZ656-658.
&&
$$
SYNOPSIS...JDM
NEAR TERM...JDM/MAS
SHORT TERM...JDM
LONG TERM...LKB
AVIATION...BMD
MARINE...BMD
EQUIPMENT...AKQ
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
402 AM EST SAT JAN 18 2014
.SYNOPSIS...
THE COMBINATION OF A WEAKENING UPPER DISTURBANCE AND A DEVELOPING
AREA OF LOW PRESSURE OFF THE NEW JERSEY COAST WILL BRING LIGHT
SNOW TO PORTIONS OF THE NORTH COUNTRY TODAY BEFORE TAPERING OFF
TONIGHT. MORE SNOW SHOWERS AND POSSIBLE SNOW SQUALLS ARE EXPECTED
ON SUNDAY AHEAD OF AN ARCTIC COLD FRONT...WHICH WILL MOVE THROUGH
THE REGION SUNDAY NIGHT THROUGH EARLY MONDAY. BITTERLY COLD AIR
WILL FOLLOW THE FRONT FOR ALL OF NEXT WEEK...WITH HIGHS IN THE
SINGLE DIGITS TO LOW TEENS ABOVE ZERO...AND LOWS IN THE SINGLE
DIGITS TO TEENS BELOW.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 400 AM EST SATURDAY...CHALLENGING FORECAST OVER THE NEXT 24
HOURS AS MODELS CONTINUE TO STRUGGLE TO RESOLVE SURFACE AND MID
LEVEL FEATURES AND THEIR ASSOCIATED MOISTURE AND LIFT. HAVE MADE
SEVERAL MODIFICATIONS FROM THE PREVIOUS FORECAST BASED ON CHANGES
IN GUIDANCE...GENERALLY OFFERING MUCH LESS SNOW (SIGH) ACROSS
MOST OF THE NORTH COUNTRY TODAY AND TONIGHT.
AS HAS BEEN THE CASE OVER THE LAST FEW DAYS...LATEST RUC/RAP AND
LOCAL 6KM WRF (ALSO RUC BASED) HAVE HANDLED THE FIRST 18 HOURS OF
THE FORECAST VERY WELL DUE TO INITIALIZATION INCLUDING LATEST
SATELLITE AND RADAR DATA...AND THE SAME GOES FOR TODAY. THUS HAVE
LEANED ON THEM HEAVILY FOR THE NEAR TERM FORECAST. OVERALL SYNOPTIC
SETUP FEATURES A WEAKENING MID-LEVEL SHORTWAVE OVER THE OHIO
RIVER VALLEY THIS MORNING...WHILE SURFACE LOW PRESSURE IS
BEGINNING TO DEVELOP OFF THE NJ COAST. AS BOTH OF THESE FEATURES
SHIFT NORTH/NORTHEAST THE BTV CWA IS BASICALLY SQUEEZED BETWEEN
THE 2 SYSTEMS WITH MOISTURE TO OUR SOUTHWEST AND SOUTHEAST AND
GENERALLY DRY SURFACE TO MID-LEVEL AIR IN-BETWEEN AS IS EVIDENT
BY CURRENT CLEAR SKIES ON REGIONAL IR. PRECIP ASSOCIATED WITH THESE
FEATURE DOES FILTER INTO PORTIONS OF THE FORECAST AREA TODAY
THOUGH...MAINLY ACROSS THE ST. LAWRENCE VALLEY AND SOUTHEASTERN
VERMONT DURING THE MID-MORNING HOURS...BUT AREAS IN-BETWEEN WILL
LIKELY SEE LITTLE THROUGH THE DAY UNDER PARTLY TO MOSTLY CLOUDY
SKIES. WHERE PRECIP DOES FALL...IT`LL BE IN THE FORM OF SNOW AND
WE`LL SEE SOME LIGHT ACCUMULATIONS OF GENERALLY 1-3". HIGHS TODAY
WILL REMAIN ON THE MILD SIDE OF NORMAL...WARMEST WHERE MORE
SUNSHINE WILL BE POSSIBLE IN THE CHAMPLAIN VALLEY AND NORTHERN
VERMONT...GENERALLY LOWER TO MID 30S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/...
AS OF 356 AM EST SATURDAY...FOR TONIGHT...AFOREMENTIONED
SHORTWAVE AND COASTAL LOW SHIFT NORTHWARD ENOUGH TO SPILL SOME
MOISTURE INTO CENTRAL PORTIONS OF THE FORECAST AREA BUT BY THAT
TIME THE DEEPEST MOISTURE IS OFFSHORE AND TO OUR NORTHWEST SO
HAVE ONLY OFFERED CHANCE POPS WITH A DUSTING TO POSSIBLY AN INCH
OF ADDITIONAL ACCUMULATION ACROSS THE ENTIRE AREA. BEST CHANCE FOR
SNOW SHOWERS TONIGHT WILL BE DOWNWIND OF LAKE ONTARIO AS SURFACE
AND MID-LEVEL FLOW TURNS SOUTHWESTERLY AFTER MIDNIGHT ALLOWING FOR
FOR ENHANCED LAKE EFFECT. UNDER CLOUDY SKIES OVERNIGHT LOWS REMAIN
MILD IN THE TEENS TO MID 20S.
ACTIVE WEATHER CONTINUES GOING INTO SUNDAY AS THE NORTH COUNTRY
WILL BE IMPACTED BY YET ANOTHER SHORTWAVE ROUNDING THE BASE OF THE
PERSISTENT BROAD UPPER TROUGH OVER THE EASTERN CONUS. IT`S
CURRENTLY MOVING THROUGH THE DAKOTAS THIS MORNING AND WILL TRACK
THROUGH THE OHIO RIVER VALLEY TONIGHT AND INTO THE MID-ATLANTIC
STATES SUNDAY. MEANWHILE TO OUR NORTHWEST...AN ARCTIC COLD FRONT
APPROACHES THE REGION AND THE COMBINATION OF THESE 2 FEATURES WILL
RENEW CHANCES FOR SNOW SHOWERS AND POSSIBLE SNOW SQUALLS SUNDAY
AFTERNOON AND EVENING BEFORE TAPERING OFF AFTER MIDNIGHT. ANOTHER
ROUND OF ACCUMULATING SNOW IS LIKELY ACROSS THE ENTIRE AREA WITH
AMOUNT GENERALLY 1-3" AGAIN...THOUGH COULD SEE SOME HIGHER AMOUNTS
ACROSS THE NORTHERN GREENS THROUGH SUNDAY NIGHT.
WE REMAIN UNDER THE INFLUENCE OF BROAD UPPER TROUGHINESS FOR
MONDAY AS WELL THOUGH FLOW IS GENERALLY WESTERLY AND DRIER WITH
JUST SOME CHANCE POPS ACROSS THE HIGHER TERRAIN FOR LIGHT SNOW
SHOWERS. MONDAY WILL MARK THE FIRST DAY IN AWHILE THOUGH THAT
WE`LL GO BELOW NORMAL FOR TEMPS WITH EXPECTED HIGHS ONLY IN THE
SINGLE NUMBERS TO TEENS. COLDER AIR MOVES IN FOR MONDAY NIGHT
ONWARD AS THE ARCTIC FRONT DROPS THROUGH THE REGION...MORE ON THAT
BELOW.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
AS OF 215 AM EST SATURDAY...QUIET...ALBEIT VERY COLD WEATHER ON
TAP FOR THE MIDDLE AND LATER PORTIONS OF NEXT WEEK WITH 00Z MODELS
REMAINING IN GOOD AGREEMENT SHOWING A PRONOUNCED RETURN OF ARCTIC
AIR TO THE NERN QUARTER OF THE NATION AND REMINDING US ALL THAT
IT`S STILL JANUARY. WE`RE NOT TALKING RECORD COLD BY ANY
MEANS...AND LOOKING AT RECENT TRENDS IN THE GUIDANCE THE COMING
COLD SNAP WILL LIKELY BE JUST A TAD MILDER THAN IT`S COUNTERPART
EARLIER THIS MONTH IF ANY SOLACE CAN BE TAKEN. THAT SAID IT WON`T
BE THAT PLEASANT AS DAYTIME HIGHS RANGE FROM -5F TO +5F TUE/WED
AND MODERATING ONLY VERY SLOWLY THU/FRI BY ABOUT 5 DEG EACH DAY.
LOWS GENERALLY IN THE -5F TO -15F RANGE MON NT/WED NT/THU NT WITH
COLDEST NIGHT LIKELY TUESDAY NIGHT WHEN VALUES SHOULD BOTTOM OUT
FROM 10 TO 20 BELOW. IN TERMS OF SENSIBLE WEATHER A PRETTY BORING
PATTERN HOWEVER. OUTSIDE SOME POSSIBLE WIND CHILL ISSUES MONDAY
NIGHT...NOT MUCH TO TALK ABOUT OTHER THAN THE COLD AS ARCTIC HIGH
PRESSURE MAINTAINS BROAD SYNOPTIC SCALE SUBSIDENCE AND DRY WEATHER
ACROSS THE AREA. BY FRIDAY NIGHT/SATURDAY...SOME HINTS AT A WEAK
NRN STREAM CLIPPER LOW POSSIBLY SPARKING SOME WARM ADVECTION-
DRIVEN LIGHT SNOWS/SHSN ACROSS THE AREA BUT NOTHING MORE THAN
TOKEN 30/40 POPS AT THIS POINT GIVEN WE`RE TALKING 7 DAYS OUT.
&&
.AVIATION /09Z SATURDAY THROUGH WEDNESDAY/...
THROUGH 06Z SUNDAY...MAINLY VFR CONDS EXPECTED THROUGH 18Z UNDER
LIGHT FLOW LESS THAN 10 KTS. SOME BKN/OVC VFR CIGS DURING THIS
PERIOD...BUT GENERALLY AT 060 AGL AND ABOVE. AFTER 18Z BKN/OVC
CIGS GRADUALLY LOWER WITH PERIODS OF MVFR AND/OR IFR LIGHT SNOW
POSSIBLE...ESP AT KMPV/KRUT AND KMSS. WINDS LIGHT...THOUGH
TRENDING NORTH TO NORTHEASTERLY THROUGH TIME.
OUTLOOK 06Z SUNDAY THROUGH WEDNESDAY...SFC LOW PRES WL PRODUCE
OCCASIONAL SNOW SHOWERS ON SAT NIGHT INTO SUNDAY WITH PERIODS OF
IFR/LIFR CONDITIONS LIKELY. AN ARCTIC FRNT WL PRODUCE ADDITIONAL
SCATTERED SNOW SHOWERS WITH MAYBE A SNOW SQUALL SUNDAY EVENING
INTO MONDAY WITH MORE MVFR/IFR CONDITIONS POSSIBLE. GENERAL CLRING
WITH VFR CONDITIONS WL RETURN FOR MONDAY INTO TUESDAY ASSOCIATED
WITH ARCTIC HIGH PRES.
&&
.EQUIPMENT...
AS OF 400 AM EST SATURDAY...THE KTYX 88D DOPPLER RADAR LOCATED IN
NORTHERN NEW YORK REMAINS OUT OF SERVICE DUE TO A FAILED POWER
SUPPLY. PARTS ARE ON ORDER TO REPAIR THE PROBLEM BUT IT WILL
LIKELY BE OUT OF SERVICE THROUGH AT LEAST TUESDAY JANUARY 21.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...LAHIFF
NEAR TERM...LAHIFF
SHORT TERM...LAHIFF
LONG TERM...JMG
AVIATION...BANACOS/JMG
EQUIPMENT...WFO BTV
AREA FORECAST DISCUSSION
NWS BISMARCK ND
103 AM CST SAT JAN 18 2014
.UPDATE...
ISSUED AT 103 AM CST SAT JAN 18 2014
CENTER OF THE SURFACE LOW CLIPPER WAS BETWEEN DEVILS LAKE AND GRAND
FORKS AND MOVING SOUTHEAST.
SUSTAINED WINDS OF AT LEAST 30 MPH WITH GUSTS TO AROUND 40 MPH WERE
COMMON ACROSS MOST OF CENTRAL AND PARTS OF WESTERN NORTH DAKOTA.
HIGHEST WINDS AND GUSTS WERE REPORTED IN THE ROLETTE COUNTY AREA.
THUS FORECAST WINDS ARE IN VERY GOOD SHAPE FOR THE OVERNIGHT HOURS.
LATEST RADAR LOOPS FROM CANADIAN AND NORTH DAKOTA RADARS INDICATING
SNOW SHOWERS EXTENDING FARTHER WEST THAN PREVIOUSLY THOUGHT. ALSO
MORE CONFIDENT THAT SNOW WILL OCCUR IN THE TURTLE MOUNTAINS TO JAMES
RIVER VALLEY...SO RAISED CHANCES TO "LIKELY" THERE. LOOKING LIKE
FARTHER WEST THE RUC13 AND NAM INDICATING SCATTERED SNOW SHOWERS
ACROSS THE REST OF CENTRAL NORTH DAKOTA OVERNIGHT. RADAR LOOPS
SHOWING SNOW SHOWERS AS FAR WEST AS STANLEY...WITH MORE MOVING SOUTH
OUT OF CANADA.
HEADLINES FOR WIND ADVISORY AND WINTER WEATHER ADVISORY STILL OK.
WAS CONCERNED ABOUT THE TURTLE MOUNTAIN/PIERCE COUNTY AREA...BUT
LOOKS LIKE SNOW SHOWERS SHOULD NOT LAST THERE VERY LONG.
UPDATE ISSUED AT 949 PM CST FRI JAN 17 2014
THE MINOT AIR FORCE BASE REPORTED A WIND GUST OF 47 MPH ABOUT AN
HOUR AGO. THE ROLLA AIRPORT REPORTED A GUST OF 46 MPH WITHIN THE
LAST HOUR AS WELL. WINDS MEETING WIND ADVISORY CRITERIA WILL CONTINUE
TO PUSH SOUTH COINCIDENT WITH THE MOST UNSTABLE BOUNDARY LAYER
LAPSE RATES. THESE HIGHER WINDS ARE MOVING SOUTH ACROSS THE STATE ON
SCHEDULE SO WILL NOT ADJUST THE HEADLINES FOR THIS UPDATE. ONLY
ADJUSTED HOURLY SENSIBLE WEATHER BASED ON CURRENT OBS/TRENDS. THE
FRESHENED UP PRODUCTS HAVE BEEN SENT.
UPDATE ISSUED AT 707 PM CST FRI JAN 17 2014
IN RESPONSE TO AN APPROACHING CLIPPER...BOTH THE GFS AND ECMWF
PROG 50 KNOTS OF WIND DEVELOPING AT 850MB AROUND 06Z TONIGHT. LOW-
LEVEL (1000MB-850MB) LAPSE RATES GO FROM AROUND 6 C/KM AT 06Z...TO
ALMOST 7 C/KM AT 12Z SATURDAY OVER WESTERN NORTH DAKOTA. EVEN
THOUGH ALL 50 KNOTS OF MOMENTUM ARE NOT EXPECTED TO MIX TO THE
SURFACE...AT LEAST 40 KNOTS SHOULD BE REALIZED AT THE SURFACE. AS
A RESULT...INCREASED THE FIRST PERIOD WIND FORECAST WEST AND EXPANDED
THE WIND ADVISORY WEST TO ENCAPSULATE THE REMAINING NORTH DAKOTA
COUNTIES. THE UPDATED PRODUCTS HAVE BEEN SENT.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 308 PM CST FRI JAN 17 2014
12 UTC MODEL/ENSEMBLE GUIDANCE SUPPORTS WESTWARD EXPANSION OF THE
WIND ADVISORY TO INCLUDE A FEW MORE COUNTIES IN THE
SOUTHWEST/SOUTH CENTRAL. BUFKIT SOUNDINGS FROM THE 09/15 UTC SREF
MEAN/NAM/GFS ALL INDICATE SUFFICIENT DOWNWARD MOMENTUM FLUX TO
INCREASE WIND FORECASTS AND EXPAND THE ADVISORY.
FURTHER EAST IN THE JAMES RIVER VALLEY...THE WIND ADVISORY WAS
REPLACED BY A WINTER WEATHER ADVISORY. LIGHT SNOW AHEAD OF
STRONGER WINDS THIS EVENING LOOKS TO BE SUFFICIENT FOR SUBSTANTIAL
REDUCTIONS IN VISIBILITY DUE TO BLOWING SNOW. MOREOVER...IF SNOW
IS SLOWER TO EXIT OR WIND IS EARLY...NEAR BLIZZARD CONDITIONS WILL
RESULT. THE AFOREMENTIONED UNCERTAINTY WILL EXIST UNTIL THE EVENT
IS UNDERWAY.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 308 PM CST FRI JAN 17 2014
THE NORTHERN PLAINS REMAINS IN NORTHWEST FLOW ALOFT THROUGH THE LONG
TERM PERIOD. SEVERAL CLIPPER SYSTEMS ARE FORECAST BY 12Z MODELS
(GFS/EC/GEM) TO IMPACT THE REGION LATE THIS WEEKEND AND WELL THROUGH
NEXT WEEK.
THE FIRST IN A SERIES OF FAST MOVING CLIPPERS WILL MOVE ACROSS THE
NORTHERN PLAINS/UPPER MIDWEST DURING THE DAY SUNDAY...FOLLOWED
QUICKLY BY TWO MORE WAVES SUNDAY NIGHT AND ANOTHER ON MONDAY. BEFORE
SUNDAYS WAVE...WAA WITH 850MB TEMPS +4 TO +8C AND A 15-20KT WESTERLY
MIXING WIND SHOULD MAINTAIN RELATIVELY MILD OVERNIGHT LOWS WITH
TEMPERATURES SUNDAY MORNING IN THE MID 20S TO MID 30S. WILL NOT SEE
MUCH TEMPERATURE RECOVERY SUNDAY DAYTIME WITH ALL MODELS BRINGING A
COLD FRONT NORTHEAST TO SOUTHWEST ACROSS NORTH DAKOTA. CHANCES FOR
SNOW WILL ACCOMPANY THE FRONT/CAA NORTHEAST SUNDAY
MORNING...SPREADING SOUTH AND WEST SUNDAY AFTERNOON INTO SUNDAY
NIGHT AS CAA CONTINUES TO SPREAD SOUTHWEST. THE NEXT TWO EMBEDDED
WAVES WILL DRIVE THE FRONTAL ZONE FARTHER SOUTHWEST SUNDAY NIGHT
INTO MONDAY. EXPECT ANY SNOW TO END BY MONDAY EVENING AS THE THIRD
MID LEVEL IMPULSE/CLIPPER MOVES SOUTHEAST OUT OF THE REGION.
TEMPERATURES WILL BE NOTICEABLY COLDER ON MONDAY WITH HIGHS AROUND
ZERO ACROSS THE TURTLE MOUNTAINS TO THE LOW/MID 20S SOUTHWEST. LOWS
TUESDAY MORNING WILL RANGE FROM 10 BELOW EAST TO 10 ABOVE WEST AS A
COLD 1040MB AREA OF HIGH PRESSURE BUILDS SOUTH ACROSS THE EASTERN
DAKOTAS.
STRONGEST WINDS SUNDAY THROUGH MONDAY DAYTIME WILL BE ACROSS THE
WESTERN HALF OF THE DAKOTAS...ALONG TO WEST OF THE TRACK OF THE
SURFACE LOW PRESSURE SYSTEMS. AT THIS TIME WINDS ARE EXPECTED TO
REMAIN SUB-ADVISORY AS WE NEVER REALLY DEVELOP THE STRONG PRESSURE
RISES AS WE SAW ON THURSDAY MORNING OR WHAT WE WILL SEE LATE TONIGHT
CENTRAL AND EAST. STILL...WILL HAVE TO MONITOR THE HIGHER TERRAIN OF
THE FAR SOUTHWEST IN CASE GRADIENT FORCING INCREASES WITH FUTURE
MODEL RUNS.
YET ANOTHER WEAK CLIPPER/FRONTAL PASSAGE ARRIVES MID-WEEK...FOLLOWED
BY THE POTENTIAL FOR ANOTHER ARCTIC COLD SNAP THE FOLLOWING WEEKEND.
WILL NOT GET INTO DETAILS REGARDING ANYTHING PAST TUESDAY UNTIL
MODELS COME INTO BETTER ALIGNMENT AND WE PASS THE THREATS OR
POTENTIAL THREATS OVER THE NEXT FEW DAYS THROUGH MONDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 103 AM CST SAT JAN 18 2014
MVFR CIGS WILL OVERSPREAD THE STATE FROM NORTH TO SOUTH THROUGH
THE OVERNIGHT HOURS. THERE IS A CHANCE OF LIGHT SNOW AT
KMOT/KJMS/KBIS WITH BLOWING SNOW POSSIBLE AS WELL. NORTHWESTERLY
WINDS WILL GUST TO 40 KNOTS. WINDS TO DECREASE FROM NORTHWEST TO
SOUTHEAST BEGINNING AFTER 13Z. LIFR CONDITIONS IN BLOWING SNOW IS
EXPECTED TO DEVELOP OVER KJMS BETWEEN 09Z-13Z...WITH ONLY MVFR
CIGS FROM KISN-KMOT-KDIK-KBIS GENERALLY DURING THE SAME PERIOD.
VFR CONDITIONS ARE EXPECTED AREAWIDE BY SATURDAY AFTERNOON.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 8 AM CST THIS MORNING FOR NDZ001>005-009>013-
017>019-021.
WIND ADVISORY UNTIL 7 AM MST THIS MORNING FOR NDZ031>033-040-043.
WIND ADVISORY UNTIL NOON CST /11 AM MST/ TODAY FOR NDZ020-022-
023-034>036-041-042-044>047-050.
WINTER WEATHER ADVISORY UNTIL NOON CST TODAY FOR NDZ025-037-048-
051.
&&
$$
UPDATE...JV
SHORT TERM...SCHECK
LONG TERM...NH
AVIATION...JV
AREA FORECAST DISCUSSION...UPDATED
NWS MEDFORD OR
955 PM PST FRI JAN 17 2014
AVIATION SECTION UPDATED FOR 06Z TAF ISSUANCE
.UPDATE...
AN UPDATE HAS BEEN MADE THIS EVENING TO ADJUST TEMPERATURES,
MOSTLY DOWN, A BIT. ADJUSTMENTS WERE ALSO MADE TO ADDRESS SKY
COVER AND FOG RELATED TO A SOUTHERLY STRATUS SURGE OVER THE
COASTAL WATERS AND FROM THE WEST SLOPES OF THE COAST RANGE
WESTWARD. SKY AND FOG COVERAGE WAS ALSO FINE TUNED, PRIMARILY TO
ACCOUNT FOR A DENSE FREEZING FOG ADVISORY IN THE VALLEYS OF
JACKSON AND JOSEPHINE COUNTIES.
&&
.DISCUSSION...
A STRATUS SURGE HAS REACHED THE COAST FROM THE SOUTHWEST THIS
EVENING. THE ONLY MODEL THAT DID A GOOD JOB PICKING UP ON THIS
FEATURE IS THE HRRR-3KM, SO HAVE FOLLOWED IT WITH UPDATES THROUGH
THE MORNING.
ON SATURDAY WE DO EXPECT FOG WILL LIKELY DISSIPATE COMPLETELY
DURING THE AFTERNOON ACROSS ALL WEST SIDE VALLEYS DUE TO SOME
COOLING ABOVE THE BOUNDARY LAYER AND LESS SUBSIDENCE OVER THE
AREA. HOWEVER, THIS IS NOT A GUARANTEE, AS CHANGES ARE SUBTLE.
ALSO, IN SIMILAR PAST CASES, WITH THE FLOW ALOFT TURNING FROM
SOUTHEAST TO SOUTH TO SOUTHWEST, ROSEBURG OFTEN HAS A TOUGHER
TIME SHAKING THE STRATUS. HOWEVER, TRENDS IN TEMPERATURES AND THE
INVERSION TODAY SUGGEST IT SHOULD CLEAR FOR AT LEAST A FEW HOURS
IN THE AFTERNOON AND EVENING.
PLEASE SEE THE CLIMATE SECTION FOR LONG TERM INFORMATION.
&&
.AVIATION...BASED ON THE 18/06Z TAF CYCLE...
A STRATUS SURGE HAS REACHED PORTIONS OF THE COAST THIS EVENING, WITH
NORTH BEND MOSTLY UNDER IT AND BROOKINGS ABOVE IT. THE HRRR 3KM
MODEL, WHICH HAS BEEN DOING QUITE WELL ALONG THE COAST THIS EVENING,
INDICATES THIS IFR TO LIFR FOG AND STRATUS WILL MOVE MORE
DEFINITIVELY ONTO THE COAST BETWEEN 08Z AND 09Z. THEREFORE, EXPECT
THAT NORTH BEND WILL LIKELY HAVE IFR STRATUS AND FOG THIS EVENING
THROUGH THE MORNING, AS WILL OTHER AREAS WEST OF AND ON THE WEST
SLOPES OF THE COAST RANGE. ELSEWHERE, FOG AND LOW CLOUDS OF THE LIFR
VARIETY ARE EXPECTED AGAIN IN THE SAME WEST SIDE VALLEYS AS THE LAST
FEW DAYS. ON THE EAST SIDE A SLIGHT RISE IN TEMPERATURES TONIGHT
MEANS FOG SHOULD BE A LITTLE LESS IN COVERAGE AND DURATION. A WEAKER
INVERSION DUE TO COOLING AT THE TOP OF THE BOUNDARY LAYER ON
SATURDAY SHOULD BE ENOUGH FOR ALL LOCATIONS TO CLEAR OUT. SIMILAR
PAST SCENARIOS INDICATE THAT ROSEBURG MAY BE THE LAST TO CLEAR
SATURDAY AFTERNOON. BTL
&&
.MARINE...
SOUTH WINDS WILL BECOME NORTHERLY DURING THE DAYLIGHT HOURS OF
SATURDAY. LOW CLOUDS AND SOME FOG OVER THE WATERS TONIGHT SHOULD
LIFT TOWARD MORNING AND THROUGH THE DAY ON SATURDAY DUE TO COOLING
AT THE TOP OF THE BOUNDARY LAYER. WEST SWELL WILL BE ON THE INCREASE
THIS WEEKEND, LIKELY REACHING 10 FEET SATURDAY NIGHT INTO SUNDAY.
THIS WEST SWELL WILL BE REINVIGORATED AT TIMES NEXT WEEK, REMAINING
SOMEWHAT ELEVATED IN THE 8 TO 12 FOOT RANGE. PERIODS WILL BE MOSTLY
LONG.
&&
.CLIMATE...
THE WEEK 2 FORECAST FROM WPC INDICATES NEAR NORMAL PRECIPITATION
FOR US FOR THE LAST WEEK OF JANUARY. THIS IS BASED ON AN AREA OF
INTENSE TROPICAL CONVECTION THAT IS EXPECTED TO MOVE EAST FROM
INDONESIA TOWARD THE INTERNATIONAL DATELINE PROPAGATING OUT ROSSY
WAVE ENERGY THAT SHOULD UNDERCUT THE WEST COAST RIDGE. THIS IS
INDEED RELATED TO THE MJO. THERE HAVE BEEN HINTS OF THIS IN THE
LONG RANGE GUIDANCE OVER THE LAST 3 DAYS OR SO, BUT ALL
OPERATIONAL MODELS ARE NOT ON BOARD WITH THIS JUST YET. COUPLED
OCEAN-ATMOSPHERIC MODEL CONSENSUS INDICATES THIS RIPPLE WILL REACH
US CLOSER TO THE END OF THE MONTH, AROUND THE 30TH. AT THIS POINT
IT DOES APPEAR INCREASINGLY LIKELY THAT WE WILL SEE STORM ACTIVITY
RETURN TO OUR AREA AROUND THE END OF THE MONTH INTO THE FIRST WEEK
OF FEBRUARY. STAY TUNED, AS TIMING WITH SUCH FEATURES IS OFTEN
FICKLE. BTL
&&
.PREV DISCUSSION... /ISSUED 304 PM PST FRI JAN 17 2014/
SHORT TERM...EXPECT LITTLE CHANGE IN THE WEATHER PATTERN THIS
WEEKEND AS THE STRONG RIDGE CONTINUES TO GIVE US DRY AND STABLE
PATTERN. THERE WILL BE SMALL SUBTLE CHANGES EACH DAY DEPENDING ON
HOW HIGH THE INVERSION TOP IS AS WELL AS LOW LEVEL WINDS ABOVE THE
GROUND. FOR THIS WEEKEND BOTH GUIDANCE SHOW INVERSION HEIGHTS TO
BE SIMILAR EACH DAY BUT WITH A MORE VARIABLE WINDS LESS THAN 5 MPH
IN THE MIXED LAYER. AS A RESULT I DON`T SEE THE SURROUND HILLS OF
THE ROGUE VALLEY CLEARING..AND HAVE KEPT HIGHS RELATIVELY COOL.
OUTSIDE SW OREGON AND NORTHERN CALIFORNIA VALLEYS...MILD
TEMPERATURES WILL CONTINUE. AT THE COAST LOW LEVEL FLOW IS TURNING
AWAY FROM OFFSHORE EAST-NORTHEASTERLY. HIGHS MAY DECREASE CLOSER
TO SEASONAL NORMS ALTHOUGH THE COASTAL MOUNTAINS WILL CONTINUE TO
BE VERY WARM AND DRY THROUGH THE WEEKEND.
LONG TERM...TUESDAY THROUGH FRIDAY NIGHT.
LONG TERM MODELS ARE IN GOOD AGREEMENT...DEPICTING A VERY QUIET AND
DRY PATTERN UNDER HIGH PRESSURE THROUGHOUT THE LONG TERM...HOWEVER
SOLUTIONS ALSO DEPICT A WEAK CLOSED LOW PUSHING UNDERNEATH AN
AMPLIFIED EASTERN PACIFIC RIDGE AND ENTERING THE FORECAST AREA LATE
IN THE WEEK...ALTHOUGH AT THIS POINT THE FEATURE DOES NOT APPEAR
STRONG ENOUGH TO PRODUCE ANY MORE THAN SLIGHT CHANCES OF
PRECIPITATION OVER SOME OF THE RIDGES...OR TO BREAK THE INVERSION
AND SIGNIFICANTLY CLEAR THE FOG OR STAGNANT AIR FROM THE AREA
VALLEYS. /BPN
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...AIR STAGNATION ADVISORY UNTIL 4 AM PST SATURDAY FOR
ORZ023-024-026.
AIR STAGNATION ADVISORY UNTIL 4 AM PST SATURDAY FOR ORZ029>031.
FREEZING FOG ADVISORY UNTIL 10 AM PST SATURDAY FOR ORZ024-026.
CA...NONE.
PACIFIC COASTAL WATERS...NONE.
$$
BTL
AREA FORECAST DISCUSSION
NWS MEDFORD OR
923 PM PST FRI JAN 17 2014
.UPDATE...
AN UPDATE HAS BEEN MADE THIS EVENING TO ADJUST TEMPERATURES,
MOSTLY DOWN, A BIT. ADJUSTMENTS WERE ALSO MADE TO ADDRESS SKY
COVER AND FOG RELATED TO A SOUTHERLY STRATUS SURGE OVER THE
COASTAL WATERS AND FROM THE WEST SLOPES OF THE COAST RANGE
WESTWARD. SKY AND FOG COVERAGE WAS ALSO FINE TUNED, PRIMARILY TO
ACCOUNT FOR A DENSE FREEZING FOG ADVISORY IN THE VALLEYS OF
JACKSON AND JOSEPHINE COUNTIES.
&&
.DISCUSSION...
A STRATUS SURGE HAS REACHED THE COAST FROM THE SOUTHWEST THIS
EVENING. THE ONLY MODEL THAT DID A GOOD JOB PICKING UP ON THIS
FEATURE IS THE HRRR-3KM, SO HAVE FOLLOWED IT WITH UPDATES THROUGH
THE MORNING.
ON SATURDAY WE DO EXPECT FOG WILL LIKELY DISSIPATE COMPLETELY
DURING THE AFTERNOON ACROSS ALL WEST SIDE VALLEYS DUE TO SOME
COOLING ABOVE THE BOUNDARY LAYER AND LESS SUBSIDENCE OVER THE
AREA. HOWEVER, THIS IS NOT A GUARANTEE, AS CHANGES ARE SUBTLE.
ALSO, IN SIMILAR PAST CASES, WITH THE FLOW ALOFT TURNING FROM
SOUTHEAST TO SOUTH TO SOUTHWEST, ROSEBURG OFTEN HAS A TOUGHER
TIME SHAKING THE STRATUS. HOWEVER, TRENDS IN TEMPERATURES AND THE
INVERSION TODAY SUGGEST IT SHOULD CLEAR FOR AT LEAST A FEW HOURS
IN THE AFTERNOON AND EVENING.
PLEASE SEE THE CLIMATE SECTION FOR LONG TERM INFORMATION.
&&
.AVIATION...BASED ON THE 18/00Z TAF CYCLE...
A SOUTHERLY STRATUS SURGE IS PUSHING TOWARD THE COAST AT THIS TIME.
WHILE MOST MODEL GUIDANCE SUGGESTS IT WILL NOT MAKE IT TO NORTH
BEND, CURRENT TRENDS AND THE HRRR 3KM MODEL DO INDEED HAVE IT MAKING
IT IN BEFORE THE SOUTHEAST DRAINAGE FLOW KICKS IN. THEREFORE, EXPECT
THAT NORTH BEND WILL LIKELY HAVE IFR STRATUS AND FOG THIS EVENING
THROUGH THE MORNING, AS WILL OTHER AREAS WEST OF AND ON THE WEST
SLOPES OF THE COAST RANGE. ELSEWHERE, FOG AND LOW CLOUDS OF THE LIFR
VARIETY ARE EXPECTED AGAIN IN THE SAME WEST SIDE VALLEYS AS THE LAST
FEW DAYS. ON THE EAST SIDE A SLIGHT RISE IN TEMPERATURES TONIGHT
MEANS FOG SHOULD BE A LITTLE LESS IN COVERAGE AND DURATION. A WEAKER
INVERSION DUE TO COOLING AT THE TOP OF THE BOUNDARY LAYER ON
SATURDAY MEANS ALL LOCATIONS WILL LIKELY CLEAR OUT. SIMILAR PAST
SCENARIOS INDICATE THAT ROSEBURG MAY BE THE LAST TO CLEAR SATURDAY
AFTERNOON.
&&
.MARINE...
SOUTH WINDS WILL BECOME NORTHERLY DURING THE DAYLIGHT HOURS OF
SATURDAY. LOW CLOUDS AND SOME FOG OVER THE WATERS TONIGHT SHOULD
LIFT TOWARD MORNING AND THROUGH THE DAY ON SATURDAY DUE TO COOLING
AT THE TOP OF THE BOUNDARY LAYER. WEST SWELL WILL BE ON THE INCREASE
THIS WEEKEND, LIKELY REACHING 10 FEET SATURDAY NIGHT INTO SUNDAY.
THIS WEST SWELL WILL BE REINVIGORATED AT TIMES NEXT WEEK, REMAINING
SOMEWHAT ELEVATED IN THE 8 TO 12 FOOT RANGE. PERIODS WILL BE MOSTLY
LONG.
&&
.CLIMATE...
THE WEEK 2 FORECAST FROM WPC INDICATES NEAR NORMAL PRECIPITATION
FOR US FOR THE LAST WEEK OF JANUARY. THIS IS BASED ON AN AREA OF
INTENSE TROPICAL CONVECTION THAT IS EXPECTED TO MOVE EAST FROM
INDONESIA TOWARD THE INTERNATIONAL DATELINE PROPAGATING OUT ROSSY
WAVE ENERGY THAT SHOULD UNDERCUT THE WEST COAST RIDGE. THIS IS
INDEED RELATED TO THE MJO. THERE HAVE BEEN HINTS OF THIS IN THE
LONG RANGE GUIDANCE OVER THE LAST 3 DAYS OR SO, BUT ALL
OPERATIONAL MODELS ARE NOT ON BOARD WITH THIS JUST YET. COUPLED
OCEAN-ATMOSPHERIC MODEL CONSENSUS INDICATES THIS RIPPLE WILL REACH
US CLOSER TO THE END OF THE MONTH, AROUND THE 30TH. AT THIS POINT
IT DOES APPEAR INCREASINGLY LIKELY THAT WE WILL SEE STORM ACTIVITY
RETURN TO OUR AREA AROUND THE END OF THE MONTH INTO THE FIRST WEEK
OF FEBRUARY. STAY TUNED, AS TIMING WITH SUCH FEATURES IS OFTEN
FICKLE. BTL
&&
.PREV DISCUSSION... /ISSUED 304 PM PST FRI JAN 17 2014/
SHORT TERM...EXPECT LITTLE CHANGE IN THE WEATHER PATTERN THIS
WEEKEND AS THE STRONG RIDGE CONTINUES TO GIVE US DRY AND STABLE
PATTERN. THERE WILL BE SMALL SUBTLE CHANGES EACH DAY DEPENDING ON
HOW HIGH THE INVERSION TOP IS AS WELL AS LOW LEVEL WINDS ABOVE THE
GROUND. FOR THIS WEEKEND BOTH GUIDANCE SHOW INVERSION HEIGHTS TO
BE SIMILAR EACH DAY BUT WITH A MORE VARIABLE WINDS LESS THAN 5 MPH
IN THE MIXED LAYER. AS A RESULT I DON`T SEE THE SURROUND HILLS OF
THE ROGUE VALLEY CLEARING..AND HAVE KEPT HIGHS RELATIVELY COOL.
OUTSIDE SW OREGON AND NORTHERN CALIFORNIA VALLEYS...MILD
TEMPERATURES WILL CONTINUE. AT THE COAST LOW LEVEL FLOW IS TURNING
AWAY FROM OFFSHORE EAST-NORTHEASTERLY. HIGHS MAY DECREASE CLOSER
TO SEASONAL NORMS ALTHOUGH THE COASTAL MOUNTAINS WILL CONTINUE TO
BE VERY WARM AND DRY THROUGH THE WEEKEND.
LONG TERM...TUESDAY THROUGH FRIDAY NIGHT.
LONG TERM MODELS ARE IN GOOD AGREEMENT...DEPICTING A VERY QUIET AND
DRY PATTERN UNDER HIGH PRESSURE THROUGHOUT THE LONG TERM...HOWEVER
SOLUTIONS ALSO DEPICT A WEAK CLOSED LOW PUSHING UNDERNEATH AN
AMPLIFIED EASTERN PACIFIC RIDGE AND ENTERING THE FORECAST AREA LATE
IN THE WEEK...ALTHOUGH AT THIS POINT THE FEATURE DOES NOT APPEAR
STRONG ENOUGH TO PRODUCE ANY MORE THAN SLIGHT CHANCES OF
PRECIPITATION OVER SOME OF THE RIDGES...OR TO BREAK THE INVERSION
AND SIGNIFICANTLY CLEAR THE FOG OR STAGNANT AIR FROM THE AREA
VALLEYS. /BPN
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...AIR STAGNATION ADVISORY UNTIL 4 AM PST SATURDAY FOR
ORZ023-024-026.
AIR STAGNATION ADVISORY UNTIL 4 AM PST SATURDAY FOR ORZ029>031.
FREEZING FOG ADVISORY UNTIL 10 AM PST SATURDAY FOR ORZ024-026.
CA...NONE.
PACIFIC COASTAL WATERS...NONE.
$$
BTL
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
137 AM EST SAT JAN 18 2014
.SYNOPSIS...
A STORM SYSTEM WILL FORM RAPIDLY OVER SOUTHEASTERN PA BEFORE
MOVING UP INTO NEW ENGLAND SATURDAY. OTHERWISE...A PROGRESSIVE
CYCLONIC FLOW PATTERN ALOFT WILL PERSIST ACROSS THE REGION FOR THE
NEXT SEVERAL DAYS....FEATURING THE PERIODIC PASSAGE OF SEVERAL
MOISTURE-STARVED ALBERTA CLIPPERS THAT WILL KEEP A NEARLY-CONSTANT
CHANCE OF LIGHT SNOW IN THE FORECAST. TEMPERATURES WILL BE
TRENDING NOTICEABLY COLDER INTO THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 7 AM THIS MORNING/...
1130 PM...
SNOW BAND MOVING QUICKLY TO THE NORTHEAST AND WEAKENING QUITE A
BIT. NO LTG IN LAST HOUR AND A HALF. THE NEXT WAVE IS PUSHING
NORTHWARD INTO THE MID ATLANTIC THOUGH AND ALL SEEMS ON TRACK.
SNOW SHOULD INTENSIFY SLIGHTLY IN THE S-CENTRAL COS AND SLIDE NE.
TIMING ON BACK EDGE SEEMS TO BE ENDING BEFORE 09Z IN THE FAR SRN
TIER AND EVEN BEFORE 12Z IN AREAS S OF I-80 EXCEPT THE POCONOS.
THE FAR NE WILL HAVE TO WAIT UNTIL MID-MORNING TO SEE THE SNOW
TAPER OFF ACCORDING TO LATEST HRRR AND RUC. THE FAR SERN PART OF
LANCASTER CO MAY JUST GET A DUSTING...BUT HIGHER HILLS IN THE NE
WILL TAKE RUN AROUND 4 INCHES AS CSI BANDING SUPPORT IS
MAINTAINED IN THAT AREA FOR THE LONGEST PD. AGAIN...NO CHANGE
THERE. JUST TWEAKS TO TIMING.
9 PM...
THE VERY POTENT DYNAMICS ALOFT ARE RESULTING IN LOCALLY HEAVY
THUNDER-SNOW MOVING OUT OF THE LAURELS. THINKING HAS NOT CHANGED
APPRECIABLY...WITH A GENERALIZED 1-4 INCH SNOWFALL EXPECTED
OVERNIGHT AS THE VERY UNSTABLE AIRMASS AND STRONG FRONTOGENESIS
BRINGS A FAIRLY WIDESPREAD NUISANCE SNOW TO THE AREA.
FROM EARLIER...
HAVE DECIDED TO ISSUE AN ADVISORY FOR SEVERAL
INCHES OF SNOW STARTING LATER TONIGHT AND LASTING INTO SATURDAY
MORNING. LATEST GUIDANCE SHOWS THE EXPECTED RAPID DEVELOPMENT OF
THE SURFACE LOW AS IT PASSES THROUGH VA TOWARD SERN PA/DELMARVA
AREA. THIS RESULTS IN A PERIOD OF STRONG FRONTOGENETIC FORCING
THAT DEVELOPS OVER CENTRAL AND EASTERN PA. CAPPED BY STEEP MID
LEVEL LAPSE RATES EXCEEDING 7C/KM...THE ATMOSPHERE SHOULD BE VERY
EFFICIENT IN GENERATING UPWARD VERTICAL MOTION AND LIGHT TO
MODERATE SNOW DESPITE THE RELATIVE DRYNESS OF THE AIRMASS.
&&
.SHORT TERM /7 AM THIS MORNING THROUGH 6 AM SUNDAY/...
MAIN...WELL DEFINED SHORT WAVE WILL BE MOVING ACROSS PA DURING
THIS PERIOD WITH NEW AREA OF SNOW DEVELOPING AHEAD OF IT AS LEE
CYCLOGENESIS TAKES PLACE LATER TONIGHT. BOTH LATEST GFS AND NAM
DEPICT WEAK SFC WAVE DEVELOPING BETWEEN BWI AND PHL BY EARLY SAT
MORNING...WHICH CAUSED ME TO INCREASE QP AND SNOW AMOUNTS ACROSS
THE CWA...ESP EASTERN SECTIONS. BOTH THESE MODELS AND OTHER SHORT
RANGE GUIDANCE ALSO SHOW SEVERAL INCH SWATH OF SNOW ACROSS PARTS
OF CWA...BUT NOT COINCIDENT...DURING THE 06Z TO 12Z TIME FRAME.
DESPITE THIS INCREASE IN....DO NOT HAVE CONFIDENCE IN AMOUNTS
ENOUGH TO WARRANT THE NEED TO AN ADVISORY AT THIS TIME.
ANY STEADY SNOW WILL BE ENDING AROUND SUNRISE SATURDAY AS THE
MAIN TROF AXIS PULLS AWAY FROM PA...WITH LINGERING FLURRIES
POSSIBLE INTO SAT MORNING.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
NOT MUCH TO ADD TO SATURDAY...SEE SECTION ABOVE.
FOR SATURDAY NIGHT...LEFT POPS CLOSE TO WHAT WAS IN THE GRIDS.
MAIN THING WAS NOT TO RUSH SNOW INTO NE AREAS TOO FAST BY
SUNDAY MORNING.
AS SOUTHERN WAVE MOVES OUT SUNDAY MORNING...MUCH OF THE AREA WILL
SEE SOME SUN BY AFT. IT WILL BE BREEZY OUT...AS THE NEXT SYSTEM
DROPS SE.
STRONG FRONT DROPS SE ACROSS THE AREA ON MONDAY. MAIN CHANGE
WAS TO UP TEMPS SOME PRIOR TO TUE...AS THE REAL COLD AIR IS
STILL TO THE WEST AND NORTH AT THIS POINT.
UNLIKE LAST EVENT...WINDS WILL NOT BE AS STRONG...AND COLD
AIR COMES IN MORE FROM THE NE INSTEAD OF BEING ADVECTED
IN FROM THE WEST. STILL DID LOWER TEMPS IN SOME SPOTS.
DID CUT BACK ON EXTENT OF SNOW SHOWERS SOME...MAIN AREA TO SEE
SOME SNOW SHOWERS WILL BE THE FAR NW...ALONG WITH THE UPSLOPE
AREAS OF THE WEST. SEE MENTION OF ICE COVER IN NEAR TERM
SECTION.
WENT WITH A DRY FCST FOR LATE IN THE WEEK...AS THE HIGH MOVES
EAST OF THE AREA.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
A POTENT COLD FRONT IS PUSHING THRU CENTRAL PA EARLY THIS
AM...ACCOMPANIED BY A FEW HOURS OF SNOW SHOWERS AND IFR VSBYS.
RADAR IMAGE AT 06Z SHOWS BACK EDGE OF SIGNIFICANT SNOW IS JUST
ABOUT TO REACH KUNV AND KAOO. FURTHER WEST...DRIER FLOW BEHIND
FRONT HAS REACHED KJST AND BROUGHT MARKED IMPROVEMENT. HOWEVER...AT
KBFD THE IFR CONDS MAY LINGER UNTIL NEAR DAWN...THE RESULT OF
RESIDUAL LOW LVL MOISTURE ASCENDING THE HIGH TERRAIN OF NW PA.
FURTHER EAST...SNOW JUST ABOUT TO ARRIVE AT KIPT AND KMDT AS OF
06Z. NEAR TERM MDL DATA STILL SUPPORTS ARND 3 HRS OF IFR VSBYS AT
THESE LOCATIONS AS THE FRONTAL SNOW BAND MOVES THRU. KLNS MAY ALSO
SEE A BRIEF DIP TO IFR VSBYS BTWN 08Z-10Z. HOWEVER...RADAR/MODEL
TRENDS SUGGESTS THE BULK OF THE SNOW WILL PASS TO THEIR NORTH...SO
IFR CONDS NOT AS CERTAIN.
IN WAKE OF FROPA...GUSTY WNW WINDS OF 15-25KTS WILL BE THE MAIN
AVIATION CONCERN. SUCH WINDS ARE ALREADY BEING OBSERVED AT KJST AT
06Z AND SHOULD SPREAD EAST ACROSS THE REST OF CENTRAL PA LATER
THIS MORNING. GUSTY WINDS WILL SUBSIDE BY SAT EVENING...AS SFC
RIDGE BUILDS INTO THE STATE.
OUTLOOK...
SUN...AM SNOW/REDUCED VSBYS W MTNS. PM GUSTY WINDS WITH SHSN/REDUCED
VSBYS POSS NW MTNS.
MON...AM LGT SNOW/REDUCED VSBYS POSS N MTNS.
TUE-WED...NO SIG WX EXPECTED.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
PAZ006-012-037-041-042-045-046-049>053-058.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...DANGELO/LA CORTE
SHORT TERM...DANGELO/GARTNER/MARTIN
LONG TERM...MARTIN
AVIATION...FITZGERALD
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1151 PM EST FRI JAN 17 2014
.SYNOPSIS...
A STORM SYSTEM WILL FORM RAPIDLY OVER SOUTHEASTERN PA BEFORE
MOVING UP INTO NEW ENGLAND SATURDAY. OTHERWISE...A PROGRESSIVE
CYCLONIC FLOW PATTERN ALOFT WILL PERSIST ACROSS THE REGION FOR THE
NEXT SEVERAL DAYS....FEATURING THE PERIODIC PASSAGE OF SEVERAL
MOISTURE-STARVED ALBERTA CLIPPERS THAT WILL KEEP A NEARLY-CONSTANT
CHANCE OF LIGHT SNOW IN THE FORECAST. TEMPERATURES WILL BE
TRENDING NOTICEABLY COLDER INTO THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 7 AM SATURDAY MORNING/...
1130 PM...
SNOW BAND MOVING QUICKLY TO THE NORTHEAST AND WEAKENING QUITE A
BIT. NO LTG IN LAST HOUR AND A HALF. THE NEXT WAVE IS PUSHING
NORTHWARD INTO THE MID ATLANTIC THOUGH AND ALL SEEMS ON TRACK.
SNOW SHOULD INTENSIFY SLIGHTLY IN THE S-CENTRAL COS AND SLIDE NE.
TIMING ON BACK EDGE SEEMS TO BE ENDING BEFORE 09Z IN THE FAR SRN
TIER AND EVEN BEFORE 12Z IN AREAS S OF I-80 EXCEPT THE POCONOS.
THE FAR NE WILL HAVE TO WAIT UNTIL MID-MORNING TO SEE THE SNOW
TAPER OFF ACCORDING TO LATEST HRRR AND RUC. THE FAR SERN PART OF
LANCASTER CO MAY JUST GET A DUSTING...BUT HIGHER HILLS IN THE NE
WILL TAKE RUN AROUND 4 INCHES AS CSI BANDING SUPPORT IS
MAINTAINED IN THAT AREA FOR THE LONGEST PD. AGAIN...NO CHANGE
THERE. JUST TWEAKS TO TIMING.
9 PM...
THE VERY POTENT DYNAMICS ALOFT ARE RESULTING IN LOCALLY HEAVY
THUNDER-SNOW MOVING OUT OF THE LAURELS. THINKING HAS NOT CHANGED
APPRECIABLY...WITH A GENERALIZED 1-4 INCH SNOWFALL EXPECTED
OVERNIGHT AS THE VERY UNSTABLE AIRMASS AND STRONG FRONTOGENESIS
BRINGS A FAIRLY WIDESPREAD NUISANCE SNOW TO THE AREA.
FROM EARLIER...
HAVE DECIDED TO ISSUE AN ADVISORY FOR SEVERAL
INCHES OF SNOW STARTING LATER TONIGHT AND LASTING INTO SATURDAY
MORNING. LATEST GUIDANCE SHOWS THE EXPECTED RAPID DEVELOPMENT OF
THE SURFACE LOW AS IT PASSES THROUGH VA TOWARD SERN PA/DELMARVA
AREA. THIS RESULTS IN A PERIOD OF STRONG FRONTOGENETIC FORCING
THAT DEVELOPS OVER CENTRAL AND EASTERN PA. CAPPED BY STEEP MID
LEVEL LAPSE RATES EXCEEDING 7C/KM...THE ATMOSPHERE SHOULD BE VERY
EFFICIENT IN GENERATING UPWARD VERTICAL MOTION AND LIGHT TO
MODERATE SNOW DESPITE THE RELATIVE DRYNESS OF THE AIRMASS.
&&
.SHORT TERM /7 AM SATURDAY THROUGH 6 AM SATURDAY/...
MAIN...WELL DEFINED SHORT WAVE WILL BE MOVING ACROSS PA DURING
THIS PERIOD WITH NEW AREA OF SNOW DEVELOPING AHEAD OF IT AS LEE
CYCLOGENESIS TAKES PLACE LATER TONIGHT. BOTH LATEST GFS AND NAM
DEPICT WEAK SFC WAVE DEVELOPING BETWEEN BWI AND PHL BY EARLY SAT
MORNING...WHICH CAUSED ME TO INCREASE QP AND SNOW AMOUNTS ACROSS
THE CWA...ESP EASTERN SECTIONS. BOTH THESE MODELS AND OTHER SHORT
RANGE GUIDANCE ALSO SHOW SEVERAL INCH SWATH OF SNOW ACROSS PARTS
OF CWA...BUT NOT COINCIDENT...DURING THE 06Z TO 12Z TIME FRAME.
DESPITE THIS INCREASE IN....DO NOT HAVE CONFIDENCE IN AMOUNTS
ENOUGH TO WARRANT THE NEED TO AN ADVISORY AT THIS TIME.
ANY STEADY SNOW WILL BE ENDING AROUND SUNRISE SATURDAY AS THE
MAIN TROF AXIS PULLS AWAY FROM PA...WITH LINGERING FLURRIES
POSSIBLE INTO SAT MORNING.
&&
.LONG TERM /SATURDAY THROUGH FRIDAY/...
NOT MUCH TO ADD TO SATURDAY...SEE SECTION ABOVE.
FOR SATURDAY NIGHT...LEFT POPS CLOSE TO WHAT WAS IN THE GRIDS.
MAIN THING WAS NOT TO RUSH SNOW INTO NE AREAS TOO FAST BY
SUNDAY MORNING.
AS SOUTHERN WAVE MOVES OUT SUNDAY MORNING...MUCH OF THE AREA WILL
SEE SOME SUN BY AFT. IT WILL BE BREEZY OUT...AS THE NEXT SYSTEM
DROPS SE.
STRONG FRONT DROPS SE ACROSS THE AREA ON MONDAY. MAIN CHANGE
WAS TO UP TEMPS SOME PRIOR TO TUE...AS THE REAL COLD AIR IS
STILL TO THE WEST AND NORTH AT THIS POINT.
UNLIKE LAST EVENT...WINDS WILL NOT BE AS STRONG...AND COLD
AIR COMES IN MORE FROM THE NE INSTEAD OF BEING ADVECTED
IN FROM THE WEST. STILL DID LOWER TEMPS IN SOME SPOTS.
DID CUT BACK ON EXTENT OF SNOW SHOWERS SOME...MAIN AREA TO SEE
SOME SNOW SHOWERS WILL BE THE FAR NW...ALONG WITH THE UPSLOPE
AREAS OF THE WEST. SEE MENTION OF ICE COVER IN NEAR TERM
SECTION.
WENT WITH A DRY FCST FOR LATE IN THE WEEK...AS THE HIGH MOVES
EAST OF THE AREA.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
SNOW BAND HAS WEAKENED SOME AND IS MOVG SLOWER TO THE ENE.
THEREFORE ISSUED SEVERAL AMDS TO REFLECT SLIGHTLY BETTER VISBY
TRENDS AND LATER TOA OF -SN ACRS THE ERN AIRFIELDS.
A RATHER COMPACT BUT ROBUST MID/UPPER LEVEL TROUGH WILL PIVOT ACRS
THE CENTRAL APPLCHNS LATE THIS EVE AND TAKE ON A NEGATIVE TILT AS
IT LIFTS NEWD THRU THE NRN MID-ATLC STATES LATE TONIGHT INTO EARLY
SAT. THIS POTENT ENERGY ALOFT WILL BE SUFFICIENT TO INDUCE A
DISTINCT SFC LOW THAT WILL RIDE NWD ALONG AN ATTENDANT COLD FRONT
FROM NRN VA INTO NERN PA BY 12Z SAT. A RELATIVELY NARROW AND
PROGRESSIVE AXIS OF SNOW WILL DEVELOP AND MOVE OVER THE AIRSPACE
WHICH SHOULD BRING A SEVERAL HOUR PERIOD OF REDUCED CONDS FOLLOWED
BY GUSTY WNW WINDS 15-25KTS ON THE BACKSIDE OF THE DEPARTING LOW
CENTER. THE SNOW WILL END FROM SW-NE EARLY SAT MORNING BUT GUSTY
WINDS WILL PERSIST INTO THE AFTN...BEFORE SUBSIDING INTO SAT NGT
AS RIDGE OF HIGH PRES QUICKLY SLIDES THRU CENTRAL PA.
OUTLOOK...
SUN...IFR/MVFR IN -SHSN WRN AND CNTRL AIRFIELDS. MVFR PSBL ERN
SXNS. GUSTY WSW WINDS...BCMG WNW SUN NGT.
MON...IFR/MVFR WITH OCNL -SHSN WRN SXNS...MAINLY VFR E OF THE MTNS.
TUE-WED...MVFR WEST -SHSN PSBL. MAINLY VFR CENTRAL/EAST.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 1 PM EST SATURDAY FOR PAZ006-012-
037-041-042-045-046-049>053-058.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...DANGELO/LA CORTE
SHORT TERM...DANGELO/GARTNER/MARTIN
LONG TERM...MARTIN
AVIATION...STEINBUGL
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1149 PM EST FRI JAN 17 2014
.SYNOPSIS...
A STORM SYSTEM WILL FORM RAPIDLY OVER SOUTHEASTERN PA BEFORE
MOVING UP INTO NEW ENGLAND SATURDAY. OTHERWISE...A PROGRESSIVE
CYCLONIC FLOW PATTERN ALOFT WILL PERSIST ACROSS THE REGION FOR THE
NEXT SEVERAL DAYS....FEATURING THE PERIODIC PASSAGE OF SEVERAL
MOISTURE-STARVED ALBERTA CLIPPERS THAT WILL KEEP A NEARLY-CONSTANT
CHANCE OF LIGHT SNOW IN THE FORECAST. TEMPERATURES WILL BE
TRENDING NOTICEABLY COLDER INTO THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 7 AM SATURDAY MORNING/...
1130 PM...
SNOW BAND MOVING QUICKLY TO THE NORTHEAST AND WEAKENING QUITE A
BIT. NO LTG IN LAST HOUR AND A HALF. THE NEXT WAVE IS PUSHING
NORTHWARD INTO THE MID ATLANTIC THOUGH AND ALL SEEMS ON TRACK.
SNOW SHOULD INTENSIFY SLIGHTLY IN THE S-CENTRAL COS AND SLIDE NE.
TIMING ON BACK EDGE SEEMS TO BE ENDING BEFORE 09Z IN THE FAR SRN
TIER AND EVEN BEFORE 12Z IN AREAS S OF I-80 EXCEPT THE POCONOS.
THE FAR NE WILL HAVE TO WAIT UNTIL MID-MORNING TO SEE THE SNOW
TAPER OFF ACCORDING TO LATEST HRRR AND RUC. THE FAR SERN PART OF
LANCASTER CO MAY JUST GET A DUSTING...BUT HIGHER HILLS IN THE NE
WILL TAKE RUN AROUND 4 INCHES AS CSI BANDING SUPPORT IS
MAINTAINED IN THAT AREA FOR THE LONGEST PD. AGAIN...NO CHANGE
THERE. JUST TWEAKS TO TIMING.
9 PM...
THE VERY POTENT DYNAMICS ALOFT ARE RESULTING IN LOCALLY HEAVY
THUNDER-SNOW MOVING OUT OF THE LAURELS. THINKING HAS NOT CHANGED
APPRECIABLY...WITH A GENERALIZED 1-4 INCH SNOWFALL EXPECTED
OVERNIGHT AS THE VERY UNSTABLE AIRMASS AND STRONG FRONTOGENESIS
BRINGS A FAIRLY WIDESPREAD NUISANCE SNOW TO THE AREA.
FROM EARLIER...
HAVE DECIDED TO ISSUE AN ADVISORY FOR SEVERAL
INCHES OF SNOW STARTING LATER TONIGHT AND LASTING INTO SATURDAY
MORNING. LATEST GUIDANCE SHOWS THE EXPECTED RAPID DEVELOPMENT OF
THE SURFACE LOW AS IT PASSES THROUGH VA TOWARD SERN PA/DELMARVA
AREA. THIS RESULTS IN A PERIOD OF STRONG FRONTOGENETIC FORCING
THAT DEVELOPS OVER CENTRAL AND EASTERN PA. CAPPED BY STEEP MID
LEVEL LAPSE RATES EXCEEDING 7C/KM...THE ATMOSPHERE SHOULD BE VERY
EFFICIENT IN GENERATING UPWARD VERTICAL MOTION AND LIGHT TO
MODERATE SNOW DESPITE THE RELATIVE DRYNESS OF THE AIRMASS.
&&
.SHORT TERM /7 AM SATURDAY THROUGH 6 AM SATURDAY/...
MAIN...WELL DEFINED SHORT WAVE WILL BE MOVING ACROSS PA DURING
THIS PERIOD WITH NEW AREA OF SNOW DEVELOPING AHEAD OF IT AS LEE
CYCLOGENESIS TAKES PLACE LATER TONIGHT. BOTH LATEST GFS AND NAM
DEPICT WEAK SFC WAVE DEVELOPING BETWEEN BWI AND PHL BY EARLY SAT
MORNING...WHICH CAUSED ME TO INCREASE QP AND SNOW AMOUNTS ACROSS
THE CWA...ESP EASTERN SECTIONS. BOTH THESE MODELS AND OTHER SHORT
RANGE GUIDANCE ALSO SHOW SEVERAL INCH SWATH OF SNOW ACROSS PARTS
OF CWA...BUT NOT COINCIDENT...DURING THE 06Z TO 12Z TIME FRAME.
DESPITE THIS INCREASE IN....DO NOT HAVE CONFIDENCE IN AMOUNTS
ENOUGH TO WARRANT THE NEED TO AN ADVISORY AT THIS TIME.
ANY STEADY SNOW WILL BE ENDING AROUND SUNRISE SATURDAY AS THE
MAIN TROF AXIS PULLS AWAY FROM PA...WITH LINGERING FLURRIES
POSSIBLE INTO SAT MORNING.
&&
.LONG TERM /SATURDAY THROUGH FRIDAY/...
NOT MUCH TO ADD TO SATURDAY...SEE SECTION ABOVE.
FOR SATURDAY NIGHT...LEFT POPS CLOSE TO WHAT WAS IN THE GRIDS.
MAIN THING WAS NOT TO RUSH SNOW INTO NE AREAS TOO FAST BY
SUNDAY MORNING.
AS SOUTHERN WAVE MOVES OUT SUNDAY MORNING...MUCH OF THE AREA WILL
SEE SOME SUN BY AFT. IT WILL BE BREEZY OUT...AS THE NEXT SYSTEM
DROPS SE.
STRONG FRONT DROPS SE ACROSS THE AREA ON MONDAY. MAIN CHANGE
WAS TO UP TEMPS SOME PRIOR TO TUE...AS THE REAL COLD AIR IS
STILL TO THE WEST AND NORTH AT THIS POINT.
UNLIKE LAST EVENT...WINDS WILL NOT BE AS STRONG...AND COLD
AIR COMES IN MORE FROM THE NE INSTEAD OF BEING ADVECTED
IN FROM THE WEST. STILL DID LOWER TEMPS IN SOME SPOTS.
DID CUT BACK ON EXTENT OF SNOW SHOWERS SOME...MAIN AREA TO SEE
SOME SNOW SHOWERS WILL BE THE FAR NW...ALONG WITH THE UPSLOPE
AREAS OF THE WEST. SEE MENTION OF ICE COVER IN NEAR TERM
SECTION.
WENT WITH A DRY FCST FOR LATE IN THE WEEK...AS THE HIGH MOVES
EAST OF THE AREA.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
INTENSE BAND OF +SN IS MOVG ACRS CNTRL SXNS LATE THIS EVE. +TSSN
WAS REPORTED EARLIER AT JST. EXPECT VIS TO DROP BLW AIRFIELD MINS
AT UNV BTWN 04-05Z. FOR THE 03Z UPDATE...ADJUSTED TOA OF -SN OVER
ERN TERMINALS DUE TO SLOWER TIMING /LATER ARRIVAL/ AND ISSUED
AMDS AS SNOW INTENSITY TAPERED OFF AT JST.
A RATHER COMPACT BUT ROBUST MID/UPPER LEVEL TROUGH WILL PIVOT ACRS
THE CENTRAL APPLCHNS LATE THIS EVE AND TAKE ON A NEGATIVE TILT AS
IT LIFTS NEWD THRU THE NRN MID-ATLC STATES LATE TONIGHT INTO EARLY
SAT. THIS POTENT ENERGY ALOFT WILL BE SUFFICIENT TO INDUCE A
DISTINCT SFC LOW THAT WILL RIDE NWD ALONG AN ATTENDANT COLD FRONT
FROM NRN VA INTO NERN PA BY 12Z SAT. A RELATIVELY NARROW AND
PROGRESSIVE AXIS OF SNOW WILL DEVELOP AND MOVE OVER THE AIRSPACE
WHICH SHOULD BRING A SEVERAL HOUR PERIOD OF REDUCED CONDS FOLLOWED
BY GUSTY WNW WINDS 15-25KTS ON THE BACKSIDE OF THE DEPARTING LOW
CENTER. THE SNOW WILL END FROM SW-NE EARLY SAT MORNING BUT GUSTY
WINDS WILL PERSIST INTO THE AFTN...BEFORE SUBSIDING INTO SAT NGT
AS RIDGE OF HIGH PRES QUICKLY SLIDES THRU CENTRAL PA.
OUTLOOK...
SUN...IFR/MVFR IN -SHSN WRN AND CNTRL AIRFIELDS. MVFR PSBL ERN
SXNS. GUSTY WSW WINDS...BCMG WNW SUN NGT.
MON...IFR/MVFR WITH OCNL -SHSN WRN SXNS...MAINLY VFR E OF THE MTNS.
TUE-WED...MVFR WEST -SHSN PSBL. MAINLY VFR CENTRAL/EAST.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 1 PM EST SATURDAY FOR PAZ006-012-
037-041-042-045-046-049>053-058.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...DANGELO/LA CORTE
SHORT TERM...DANGELO/GARTNER/MARTIN
LONG TERM...MARTIN
AVIATION...STEINBUGL
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
312 AM CST SAT JAN 18 2014
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 312 AM CST SAT JAN 18 2014
MAIN FORECAST CONCERN THROUGH THE SHORT TERM CENTERED ON
ACCUMULATING SNOW TODAY.
WATER VAPOR/SURFACE ANALYSIS SHOW VIGOROUS LOW PRESSURE MOVING OUT
OF EASTERN ND SOUTHEAST INTO MN. RADAR AND SURFACE OBSERVATIONS
SHOWING AN EXPANSIVE NW-SE BAND OF LIGHT TO MODERATE SNOWFALL IN
ADVANCE OF THE LOW AND ATTENDANT WARM FRONTAL BOUNDARY EXTENDING
ACROSS MOST OF MN. INDICATION OF THE STRONG BAROCLINICITY ASSOCIATED
WITH THIS WAVE EVIDENCED BY TEMPERATURES RANGING FROM THE 30S ACROSS
THE DAKOTAS TO READINGS ONLY IN THE SINGLE DIGITS ABOVE AND BELOW
ZERO ACROSS THE NWS LA CROSSE FORECAST AREA.
MODELS ALL HONED INTO PROGGED TRACK OF THE LOW...TAKING IT SOUTHEAST
INTO SOUTH CENTRAL MN BY 12Z AND THEN INTO CENTRAL IL BY SUN 00Z.
DYNAMICS FAIRLY IMPRESSIVE WITH THE SYSTEM WITH STRONG ISENTROPIC
LIFT INDICATED BY RAP ON THE 275K SURFACE AND WEAK TO MODERATE
FRONTOGENETIC FORCING IN THE 1000-700MB LAYER. BUFKIT ALSO SHOWING
AROUND 17 MICROBARS OF LIFT THROUGH THE DENDRITIC GROWTH ZONE AT
KRST EARLY ON THIS MORNING. SNOW TO LIQUID RATIOS SHOULD BE FAIRLY
HIGH AS A RESULT...SOMEWHERE IN THE 16-18 TO 1 RANGE. GIVEN THIS AND
THE TRACK OF THE LOW...HEAVIEST SNOW BAND WILL SET UP ALONG AN AXIS
FROM DODGE CENTER AND ROCHESTER THROUGH DUBUQUE IA WHERE AROUND 4 TO
LOCALLY 5 INCHES IS EXPECTED THROUGH THE DAY. AS A RESULT...A WINTER
WEATHER ADVISORY REMAINS IN EFFECT UNTIL 6 PM THIS EVENING FOR ALL
OF SOUTHEAST MN/NORTHEAST IA..AND COUNTIES IN WI BORDERING THE
MISSISSIPPI AND WISCONSIN RIVERS. LOOKS LIKE MOST OF THE
ACCUMULATING SNOW MAY BE DONE/SHIFTED SOUTHEAST OF THE AREA BEFORE
6PM...BUT SOME DRIFTING OF THE SNOW WITH INCREASING NORTH WINDS ON
THE BACKSIDE OF THE LOW MAY STILL CAUSE SOME DRIVING
DIFFICULTIES...SO WILL LET IT UP THE THE DAYSHIFT TO ASSESS THE
STATUS OF THE ADVISORY HEADLINE GOING INTO THE AFTERNOON.
OTHERWISE...TEMPERATURES TODAY EXPECTED TO MODERATE INTO THE UPPER
TEENS TO MIDDLE 20S.
A RIDGE OF HIGH PRESSURE MOVES ACROSS THE AREA TONIGHT WITH WARM AIR
ADVECTION KICKING IN AFTER MIDNIGHT. LOOK FOR LOWS OCCURRING AROUND
MIDNIGHT IN THE UPPER SINGLE DIGITS/LOWER TEENS...THEN SLOWING
CLIMBING THROUGH THE TEENS AFTER MIDNIGHT.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 312 AM CST SAT JAN 18 2014
MILDER DAY ON TAP FOR SUNDAY AS WARM AIR ADVECTION CONTINUES IN
ADVANCE OF A COLD FRONT MOVING SOUTHWARD OUT OF CANADA INTO NORTHERN
WI. LOOK FOR HIGHS TOPPING OFF IN THE MIDDLE 20S TO THE MIDDLE 30S.
THE COLD FRONT WILL CONTINUE MOVING SLOWLY SOUTHWARD ACROSS THE AREA
SUNDAY NIGHT AS A WEAK MID-LEVEL WAVE RIPPLES ALONG THE BAROCLINIC
ZONE IN PLACE. THIS WILL GIVE THE AREA A CHANCE FOR SOME VERY LIGHT
SNOWFALL.
THE COLD FRONT WILL ALSO MARK THE TRANSITION BACK TO COLDER THAN
NORMAL NORTHWEST FLOW GRIPPING THE REGION AGAIN. MODELS ALSO SHOW
VARIOUS EMBEDDED SHORTWAVE TROUGHS WITHIN THE FLOW FOR ON/OFF LIGHT
SNOW CHANCES THROUGH FRIDAY. CONFIDENCE ON TIMING THESE WAVES PRETTY
LOW AT THIS TIME WITH VARIOUS MODEL SOLUTIONS. OTHERWISE...LOOK FOR
HIGH TEMPERATURES GENERALLY IN THE SINGLE DIGITS AND TEENS ABOVE
ZERO WITH LOWS IN THE SINGLE DIGITS AND TEENS BELOW ZERO. APPEARS
WIND CHILL HEADLINES WILL LIKELY BE NEEDED MONDAY NIGHT/TUESDAY
MORNING AS WIND CHILL VALUES DIP INTO THE 20S TO NEAR 30 BELOW ZERO.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1122 PM CST FRI JAN 17 2014
THE SURFACE LOW HAS MOVED INTO EASTERN NORTH DAKOTA THIS EVENING.
REGIONAL RADARS AND OBSERVATIONS INDICATE SNOW IS FALLING ON THE
EAST SIDE OF THE LOW ACROSS NORTHWEST MINNESOTA INTO EASTERN NORTH
DAKOTA WHERE IFR CONDITIONS ARE OCCURRING. THE 18.00Z NAM CAME IN
WITH A SUBTLE EASTWARD SHIFT WITH THE TRACK OF THE SURFACE LOW
PLACING KLSE BACK INTO THE THE HEAVIER SNOW AND THE 18.01Z HRRR IS
VERY SIMILAR. HAVE ESSENTIALLY MAINTAINED THE FORECAST FOR KRST
BRINGING THE SNOW IN AROUND 10Z WITH THE VISIBILITY QUICKLY GOING
DOWN TO LESS THAN A MILE WITH IFR CEILINGS. HAVE TRENDED DOWNWARD
WITH THE KLSE FORECAST SHOWING THE SNOW COMING IN AROUND 12Z WITH
THE VISIBILITY THEN GOING DOWN TO AROUND A MILE WITH MVFR
CEILINGS. STILL EXPECTING THE SNOW TO BE FAST MOVING WITH
IMPROVEMENTS BEGINNING LATE SATURDAY MORNING AND THE SNOW THEN
ENDING BY EARLY TO MID AFTERNOON. UNSURE ON WHAT TO DO WITH THE
CEILINGS BEHIND THE SNOW AS THE NAM BUFKIT SOUNDING WOULD SUGGEST
THE LOWER CLOUDS COULD SCATTER OUT. UPSTREAM OBSERVATIONS ACROSS
EASTERN SASKATCHEWAN SHOW THE LOWER CLOUDS STILL IN PLACE SO HAVE
OPTED TO STAY WITH A MVFR CEILING BEHIND THE SNOW AT KRST AND A
LOW VFR CEILING FOR KLSE.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR WIZ032-
033-041-053>055-061.
MN...WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR MNZ079-
086>088-094>096.
IA...WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR
IAZ008>011-018-019-029-030.
&&
$$
SHORT TERM...DAS
LONG TERM....DAS
AVIATION...04
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1122 PM CST FRI JAN 17 2014
.SHORT TERM...(TONIGHT THROUGH SATURDAY NIGHT)
ISSUED AT 322 PM CST FRI JAN 17 2014
MAIN FORECAST CONCERNS THIS PACKAGE...SNOW CHANCES/AMOUNTS WITH FAST
MOVING SYSTEM LATER TONIGHT INTO EARLY SAT AFTERNOON.
DATA ANALYSIS AT 18Z HAD A COLD RIDGE OF HIGH PRESSURE SLOWLY
DRIFTING EAST ACROSS THE REGION...WITH THE LOWER CLOUDS/-SN SLOWLY
CLEARING FROM WEST TO EAST ACROSS WI/FAR EASTERN IA. SUNNY BUT COLD
CONDITIONS OVER MN/WESTERN WI/MUCH OF IA UNDER THE RIDGE. UPSTREAM
THE STRONGER PRESSURE FALLS AHEAD OF THE NEXT SYSTEM WERE ALREADY
CENTERED NEAR LK WINNIPEG. PER WV IMAGERY...SHORTWAVE FOR LATE
TONIGHT/SAT MORNING WAS QUICKLY MOVING SOUTH INTO NORTHERN SASKAT.
NO MAJOR PROBLEMS NOTED WITH 17.12Z MODEL INITIALIZATIONS. SOLUTIONS
ABOUT AS SIMILAR AS CAN BE EXPECTED FOR TONIGHT THRU SAT NIGHT AS
THE VIGOROUS SHORTWAVE INITIALIZED NORTH OF THE NW TERRITORIES/
ALBERTA LINE DIVES QUICKLY SOUTHEAST AND ACROSS THE REGION
TONIGHT/SAT. TREND OF THE MODEL SUITE CONTINUES STRONGER WITH THIS
FEATURE AS IT PASSES BUT AT LEAST THE TIMING HAS REMAINS RATHER
CONSISTENT. STILL SOME TRACK/SNOW SWATH DIFFERENCES AMONG THE MODELS
THAT WOULD HAVE IMPACTS ON THE SENSIBLE WEATHER CENTERED ON SAT
MORNING. CHECK AT 18Z SHOWED MODELS ALL LOOKING QUITE REASONABLE
WITH THE SHORTWAVE AS IT DROPS INTO NORTHERN SASKAT...VERY DIFFICULT
TO SAY IF ONE MODEL IS BETTER THAN THE OTHERS WITH THIS FEATURE
GIVEN THE OBLIQUE WV SATELLITE VIEWING ANGLE. ALL MODELS GOOD
WITH THE 12Z-18Z PRECIP OVER EASTERN WI AND ITS SLOW EXIT EAST
INTO EARLY THIS AFTERNOON. WITH NO ONE MODEL FAVORITE AND MINOR
DETAIL DIFFERENCES OVER NORTH-CENTRAL CAN HAVING IMPACTS ON THE
FCST THRU SAT...SIDED WITH THE MODEL/ENSEMBLE CONSENSUS. EVEN WITH
THE DIFFERENCE...SHORT TERM FCST CONFIDENCE REMAINS GENERALLY GOOD
THIS CYCLE.
FOR THE SHORT TERM...NORTHERN SASKAT SHORTWAVE AND ITS ATTENDANT SFC-
700MB LOW STILL ON TRACK TO SPREAD RATHER STRONG/DEEP LAYERED
FORCING/LIFT SOUTHEAST ACROSS THE FCST AREA LATE TONIGHT/SAT
MORNING. MODEL CONSENSUS FOR THE TRACK OF THE STRONGEST/DEEPEST LIFT
HAS CONTINUED TO SHIFT A BIT WEST...NOW LOOKING TO PASS ACROSS AREAS
MANLY WEST OF THE MS RIVER. HAVE TRENDED SNOW CHANCES/AMOUNTS
DOWNWARD ALONG/EAST OF I-94 FOR LATE TONIGHT/SAT. THE CONTINUED
STRONGER SOLUTIONS WITH THE SHORTWAVE AS IT PASSES BY PRODUCED
ANOTHER WESTWARD SHIFT OF THE SNOW BAND. THIS PUTS THE WINTER
WEATHER ADVISORY FOR COUNTIES FROM BUFFALO THRU LA CROSSE TO
RICHLAND IN QUESTION. APPEARS ONLY THE EXTREME WESTERN EDGE OF THESE
COUNTIES WITH A SHOT AT 3+ INCHES OF SNOW. GIVEN THE LINGERING
UNCERTAINTY WITH THE TRACK...EVEN A 20-30 MILE SHIFT EITHER WAY
WILL MEAN THE DIFFERENCE BETWEEN 1 TO 2 INCHES OF SNOW OR 3+
INCHES DOWN THE MS RIVER INTO THE BOSCOBEL/MUSCODA AREAS. LATEST
MODEL CONSENSUS HAS SHIFTED THE GREATER CHANCES OF 3 TO LOCALLY 5
INCHES OF SNOW INTO SOUTHEAST MN/NORTHEAST IA/FAR SOUTHWEST WI.
HOWEVER...WILL LEAVE THE WINTER WEATHER ADVISORY AS IS FOR
NOW...AS WOULD HATE TO UPDATE OUT OF A GOOD FCST IF A MORE EASTERN
TRACK ENDS UP MORE CORRECT OR SNOW-WATER RATIOS END UP HIGHER THAN
EXPECTED.
WITH FAST SPEED OF THE SYSTEM...TRENDED -SN CHANCES BY LATE SAT
AFTERNOON TO ONLY A 20-30 PERCENT CHANCE ACROSS THE SOUTHEAST
HALF OF THE FCST AREA. AS THE SFC-MID LEVEL TROUGH QUICKLY DEPARTS
SAT... WESTERLY LOWER LEVEL FLOW/WARM ADVECTION ALREADY SPREADS
ACROSS THE AREA SAT NIGHT. APPEARS LOWS SAT NIGHT WILL BE DURING
THE EVENING... WITH STEADY/SLOWLY RISING TEMPS OVERNIGHT.
GENERALLY USED THE MODEL/ ENSEMBLE CONSENSUS FOR LOWS/HIGHS
TONIGHT THRU SAT NIGHT.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 322 PM CST FRI JAN 17 2014
MAIN FORECAST CONCERNS FOR SUNDAY THROUGH MONDAY
NIGHT...TEMPERATURE TREND THRU THE PERIOD...SMALL -SN CHANCE
MONDAY.
BETWEEN MODEL AND RUN-T0-RUN CONSISTENCY AMONG THE MODELS REMAINS
GOOD IN THE SUN THRU MON NIGHT PERIOD AS WEAK SHORTWAVE RIDGING
QUICKLY MOVES ACROSS THE AREA SUNDAY THEN HGTS FALL AS LONGWAVE
TROUGHING DEVELOPS OVER THE EASTERN CONUS. SUN-MON NIGHT CONTINUES
TO TREND TOWARD A QUIET PERIOD AS FAR AS -SN CHANCES GO...BUT TEMPS
STILL LOOKING TO BE A ROLLER-COASTER RIDE THIS PERIOD. FCST
CONFIDENCE IN THE SUN-MON NIGHT PERIOD IS GOOD THIS CYCLE.
LOW LEVEL WARM ADVECTION INTO MID-DAY SUNDAY SENDS 925MB TEMPS INTO
THE -4C TO +4C RANGE THRU THE MORNING HOURS. THIS WARM AIR OVER THE
AREA IS SHORT LIVED GIVEN THE CONTINUED RAPID PROGRESSION OF THE
FLOW. ALL MODELS HAVE -20C OR COLDER 925MB AIR POOLED OVER ONT/LK
SUPERIOR AT 18Z. THIS WITH THE LOW LEVEL FLOW SWINGING TO THE
NORTHWEST AND NORTH BEHIND A SFC-850MB TROUGH/FRONT BEING PUSHED
SOUTH ACROSS THE AREA SUN AFTERNOON/NIGHT. BY 12Z MONDAY...925MB
TEMPS ACROSS THE AREA FALL INTO THE -10C TO -20C RANGE...AND ARE IN
THE -20C TO -22C RANGE AT 12Z TUE. AFTER ABOVE NORMAL HIGHS ON
SUNDAY...WITH LIGHT WINDS AND SOME SUNSHINE...TEMPS HEAD DOWN AND
BACK TO WELL BELOW NORMAL BY MON/MON NIGHT. NORTHWEST GRADIENT WINDS
OF 6 TO 12 MPH EXPECTED MON NIGHT...AS TEMPS FALL INTO THE -6F TO -
12F RANGE. STILL APPEARS A WIND CHILL ADVISORY WILL BE NEEDED FOR
LATE MON NIGHT/TUE MORNING. SOME 925-700MB MOISTURE ACCOMPANIES THE
MODEST SFC-700MB TROUGH/FRONT SOUTH ACROSS THE AREA SUN NIGHT...WITH
COLD CYCLONIC FLOW AND THE MID LEVEL TROUGH MOVING ACROSS THE AREA
MONDAY. ADDED A SMALL -SN/FLURRY MENTION TO SUN NIGHT GRIDS AND SCT
FLURRIES MENTION TO MON GRIDS. FAVORED WARMER OF GUIDANCE HIGHS
FOR SUN...TRENDING TOWARD COLDER OF GUIDANCE HIGHS/LOWS BY MON/MON
NIGHT.
FOR TUESDAY THROUGH FRIDAY.../DAYS 4 TO 7/...
RATHER GOOD BETWEEN MODEL AND RUN-TO-RUN CONSISTENCY AMONG 17.00Z
AND 17.12Z MEDIUM RANGE MODEL RUNS FOR COLD LONGWAVE TROUGHING TO
SET UP SHOP OVER EASTERN NOAM FOR THE TUE-FRI PERIOD. SOME
DIFFERENCES IN THE DAY-TO-DAY SHORTWAVES THRU WHAT WILL BE NORTHWEST
FLOW ALOFT OVER THE UPPER MIDWEST...BUT THIS EXPECTED IN THE DAY 4-7
TIME-FRAME. FCST CONFIDENCE HIGH THAT TEMPS WILL BE BELOW TO WELL
BELOW NORMAL TUE-FRI...BUT CONFIDENCE AVERAGE AT BEST IN ANY OF THE
DAY-TO-DAY -SN CHANCES.
850MB TEMPS LOOKING TO BE SOME 1 TO 2 STANDARD DEVIATIONS BELOW
NORMAL MUCH OF TUE-FRI UNDER THIS COLD-CORE TROUGH. 925MB TEMPS
PROGGED TO REMAIN IN THE -18C TO -22C RANGE MUCH OF THE TUE THRU
THU PERIOD. MAXES/MINS THIS PERIOD LOOKING TO BE AROUND 20F BELOW
NORMAL. A SIGNAL FOR A QUICK SHOT OF LOWER LEVEL WARM ADVECTION TO
SPREAD ACROSS THE AREA TUE NIGHT/WED AS A SFC TO MID LEVEL TROUGH
SWINGS BY AND BRINGS A RE-ENFORCING SHOT OF COLD AIR TO THE
REGION. SMALL CONSENSUS -SN CHANCES FOR TUE NIGHT/WED LOOK GOOD
FOR NOW. SOME CONSISTENCY AMONG GFS/ECMWF FOR A STRONGER ROUND OF
LOW LEVEL WARM ADVECTION TO SPREAD ACROSS THE AREA LATE IN THE
WEEK...FOR SOME MODERATION OF TEMPS INTO FRIDAY. WOULD EXPECT THIS
FORCING TO ALSO BRING WITH IT A -SN CHANCE BUT MODELS AT ODDS ON
THE TIMING OF LOWER LEVEL FEATURES BY THU/FRI. SMALL -SN CHANCE
MUCH OF THU THRU FRI REASONABLE FOR NOW. GIVEN SOME UNCERTAINTIES
CONCERNING CLOUD COVER FOR TUE-FRI...USED THE MODEL/ENSEMBLE
CONSENSUS HIGHS/LOW THRU THE DAY 4-7 PERIOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1122 PM CST FRI JAN 17 2014
THE SURFACE LOW HAS MOVED INTO EASTERN NORTH DAKOTA THIS EVENING.
REGIONAL RADARS AND OBSERVATIONS INDICATE SNOW IS FALLING ON THE
EAST SIDE OF THE LOW ACROSS NORTHWEST MINNESOTA INTO EASTERN NORTH
DAKOTA WHERE IFR CONDITIONS ARE OCCURRING. THE 18.00Z NAM CAME IN
WITH A SUBTLE EASTWARD SHIFT WITH THE TRACK OF THE SURFACE LOW
PLACING KLSE BACK INTO THE THE HEAVIER SNOW AND THE 18.01Z HRRR IS
VERY SIMILAR. HAVE ESSENTIALLY MAINTAINED THE FORECAST FOR KRST
BRINGING THE SNOW IN AROUND 10Z WITH THE VISIBILITY QUICKLY GOING
DOWN TO LESS THAN A MILE WITH IFR CEILINGS. HAVE TRENDED DOWNWARD
WITH THE KLSE FORECAST SHOWING THE SNOW COMING IN AROUND 12Z WITH
THE VISIBILITY THEN GOING DOWN TO AROUND A MILE WITH MVFR
CEILINGS. STILL EXPECTING THE SNOW TO BE FAST MOVING WITH
IMPROVEMENTS BEGINNING LATE SATURDAY MORNING AND THE SNOW THEN
ENDING BY EARLY TO MID AFTERNOON. UNSURE ON WHAT TO DO WITH THE
CEILINGS BEHIND THE SNOW AS THE NAM BUFKIT SOUNDING WOULD SUGGEST
THE LOWER CLOUDS COULD SCATTER OUT. UPSTREAM OBSERVATIONS ACROSS
EASTERN SASKATCHEWAN SHOW THE LOWER CLOUDS STILL IN PLACE SO HAVE
OPTED TO STAY WITH A MVFR CEILING BEHIND THE SNOW AT KRST AND A
LOW VFR CEILING FOR KLSE.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER WEATHER ADVISORY FROM 3 AM TO 6 PM CST SATURDAY FOR
WIZ032-033-041-053>055-061.
MN...WINTER WEATHER ADVISORY FROM 3 AM TO 6 PM CST SATURDAY FOR
MNZ079-086>088-094>096.
IA...WINTER WEATHER ADVISORY FROM 3 AM TO 6 PM CST SATURDAY FOR
IAZ008>011-018-019-029-030.
&&
$$
SHORT TERM...RRS
LONG TERM....RRS
AVIATION...04
AREA FORECAST DISCUSSION
NWS TAUNTON MA
1101 AM EST SAT JAN 18 2014
.SYNOPSIS...
DEVELOPING LOW PRESSURE WILL MOVE QUICKLY ACROSS SOUTHERN NEW
ENGLAND TODAY BUT WILL BRING A PERIOD OF ACCUMULATING SNOW TO
NORTHERN MASSACHUSETTS AND SOUTHERN NEW HAMPSHIRE. ELSEWHERE A MIX
OF SNOW AND RAIN WILL OCCUR WITH A MINOR SLUSHY ACCUMULATION
POSSIBLE. A WEAK TROUGH OF LOW PRESSURE ZIPS ACROSS THE AREA SUNDAY
BRINGING SCATTERED SNOW SHOWERS TO THE REGION. AN ARCTIC AIRMASS
WITH PUSH ACROSS THE REGION WITH PROGRESSIVELY COLDER CONDITIONS
AND BITTERLY COLD WIND CHILL VALUES BY THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
1100 AM UPDATE...
VERY BUSY MORNING SO FAR AS SYSTEM CONTINUES TO EVOLVE. HAVE
PUT ISOLATED LIGHTNING INTO THE FORECAST ESP FOR AREAS EAST OF
I-95. A FEW RUMBLES HAVE OCCURRED INLAND...EVEN HERE AT THE WFO
AND LIGHTNING HAS BEEN PICKED UP OVER THE WATERS. BEST AREA FOR
ANY RUMBLE OF THUNDER CURRENTLY WITHIN THE HIGHER ECHOES ON THE
RADAR...NEAR SHARON AND NORTON MA.
OTHERWISE SHORTWAVE IS REALLY PUSHING INTO THE REGION PER LATEST
WV IMAGERY AND APPEARS THAT THE SYSTEM IS ALREADY STARTING TO
TURN MORE NEGATIVELY. PRECIP CONTINUES TO MOVE OVER THE SAME
REGION OF EASTERN MA AND WHERE TEMPS ARE BELOW 32...EXPECT SNOW.
BECAUSE OF THIS HAVE EXPANDED THE ADVISORY FOR EASTERN
HILLSBOROUGH. AM CONCERNED HOWEVER IF WE WILL HIT ADVISORY SNOW
OUT IN WESTERN MA...WHERE PRECIP IS THE LIGHTEST. LATEST HRRR HAS
BEEN LESS GENEROUS ON THE QPF AMOUNTS OUT THERE...AND OVERALL
RADAR ECHOES HAVE BEEN LIGHT. WILL NEED TO MONITOR TO MAKE
CHANGES. HAVE ADJUSTED THE SNOW GRIDS AS SNOW ACCUMS WONT OCCUR
UNLESS TEMPS ARE AT 32F OR 33F AS WE HAVE BEEN IN A WARM SPELL FOR
SOME TIME AND SNOW WILL STRUGGLE TO ACCUMULATE AT 34F. EVEN THE
LATEST SURFACE OBS ARE SHOWING SNOW FALLING ONLY WHEN TEMPS ARE
32F OF BELOW. 33F DEGREES OR HIGHER LIKE KBDL OR KBED AT ALL SNOW.
FINALLY THE OVERALL TREND IN THE FORECAST IS ON TRACK FOR THIS
MORNING.
PREVIOUS DISCUSSION...
*** ACCUMULATING SNOW TODAY ACROSS NORTHERN MA AND SOUTHERN NH ***
00Z MODELS HAVE TRENDED STRONGER WITH IMPRESSIVE SHORT WAVE/PV
ANOMALY OVER WESTERN PA EARLY THIS MORNING. AS FOR THE
DETERMINISTIC GUIDANCE...THE 00Z NAM IS ON THE WEAKER SIDE OF THE
GUID WHILE THE GFS IS MOST ROBUST AND THE ECMWF IN THE MIDDLE OF
THE PACK. THE EURO HAS SHOWN GOOD RUN TO RUN CONTINUITY...SO A
MODEL BLEND IS VERY CLOSE TO THE ECMWF SOLUTION AND IS WHAT THIS
FORECAST IS BASED ON.
WATER VAPOR IMAGERY BEGINNING TO SHOW SIGNS OF THIS MID LEVEL
TROUGH TRANSITIONING FROM A POSITIVE TO NEUTRAL TO EVENTUALLY A
NEGATIVE TILT...THUS STRONG FORCING FOR ASCENT. SATELLITE IMAGERY
ALSO DEPICTING A DEVELOPING WARM/MOIST CONVEYOR BELT ALONG THE
EAST COAST WITH LOTS OF LIGHTNING OFF THE MID ATLC COAST. MODELS
IN GOOD AGREEMENT THAT STRONG FORCING FOR ASCENT INDUCES
CYCLOGENESIS SOUTHEAST OF NANTUCKET LATER THIS MORNING...THEN
QUICKLY RACES NORTHEAST TOWARD NOVA SCOTIA. HOWEVER STRONG FORCING
LAGS BACK TO THE NORTHWEST YIELDING AN INVERTED TROUGH ACROSS
SOUTHERN NEW ENGLAND.
AS FOR QPF...SYSTEM IS VERY PROGRESSIVE WITH PRECIP BEGINNING BY
MID MORNING AND THEN QUICKLY EXITING 21Z-00Z FROM SOUTHWEST TO
NORTHEAST. THIS WOULD SUPPORT A MINOR QPF EVENT. HOWEVER FOR A 3-6
HR WINDOW QG FORCING IS IMPRESSIVE ALONG WITH DEEP LAYER MOISTURE
AND MARGINAL INSTABILITY. THIS SUGGEST A PERIOD OF STEADY PRECIP
WITH MODERATE TO HEAVY INTENSITY. GOOD MODEL AGREEMENT THAT THIS
WILL BE CENTERED ON 18Z...SO WILL SAY 16Z-20Z FOR WINDOW OF
HEAVIEST PRECIP.
REGARDING PTYPE AND SNOWFALL...HEAVIEST PRECIP FALLS IN WARM AIR
ACROSS RI AND EASTERN MA...WITH LESS QPF IN THE COLDER AIR ACROSS
CT/WESTERN MA INTO SOUTHWEST NH. THUS A CHALLENGING AND LOW
CONFIDENCE SNOWFALL AND PTYPE FORECAST...ESPECIALLY IN THE
TRANSITION ZONE WHERE RAIN/SNOW LINE SETS UP AND THEN OSCILLATES TO
THE NW AND BACK TO THE SE. FAIRLY CONFIDENT IN THE COLDER AIRMASS
ACROSS NORTHERN MA IN THE RT-2 CORRIDOR AND WEST OF INTERSTATE
495...NORTHWARD INTO NH A MODERATE TO HIGH RISK OF 2-4 INCHES OF
SNOWFALL. HIGHEST AMOUNTS IN THE HIGHER TERRAIN GIVEN MARGINAL BLYR
AND SFC TEMPS. THUS WILL ISSUE A WINTER WEATHER ADVISORY FOR THIS
AREA.
TRICKER SNOWFALL FORECAST IS FARTHER SOUTH AND EAST...FROM
SOUTHERN WORCESTER COUNTY /MA PIKE AREA/ NORTH-NORTHEAST INTO
NORTHWEST MIDDLESEX COUNTY AND EASTERN HILLSBORO COUNTY OF NH.
THIS WOULD INCLUDE A PORTION OF THE I495 CORRIDOR OF NORTHEAST MA.
THIS IS WHERE THE RAIN/SNOW LINE WILL LIKELY OSCILLATE. QUESTION
BECOMES WILL THE FORCING BE STRONG ENOUGH TO ERODE THE BLYR WARMTH
VIA DYNAMIC AND DIABATIC COOLING PROCESSES. SOME WEAK INSTABILITY
IN THIS AREA WHICH COULD FURTHER ENHANCE UPWARD VERTICAL MOTION.
IN ADDITION...MAX OMEGA PROGGED TO OCCUR IN THE FAVORABLE SNOW
GROWTH REGION. THIS WOULD INCREASE SNOW-LIQUID-RATIOS /SLR/ AND
INCREASE THE RISK OF HEAVIER SNOW TOTALS. GIVEN THE UNCERTAINTY
HERE WILL LEAVE THIS AREA OUT OF THE ADVISORY AND FORECAST 1-2
INCHES...BUT ISSUE A SPECIAL WEATHER STATEMENT TO ADDRESS THE
SNOWFALL POTENTIAL /3-4 INCHES POSSIBLE/ IN THIS REGION. AGAIN
HEAVIEST PRECIP ANTICIPATED 16Z-20Z /11AM-3PM/. IF ALL PARAMETERS
COME TOGETHER THERE COULD BE A NARROW BAND/SWATH OF 4-6 INCHES
SOMEWHERE FROM NORTHERN WORCESTER COUNTY/NORTHWEST MIDDLESEX
COUNTY INTO HILLSBOROUGH CTY OF NH. STAY TUNED...SHOULD BE AN
EXCITING AFTERNOON!
AS FOR THE REMAINDER OF THE REGION...LOOKS SNOW TO RAIN AND
PERHAPS BACK TO SNOW BEFORE ENDING. A MINOR SLUSHY ACCUMULATION
POSSIBLE EXCEPT MAINLY RAIN IN SOUTHEAST MA INTO CENTRAL-SOUTH RI
GIVEN WARM BLYR.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
TONIGHT...
ANY LINGERING LIGHT SNOW ACROSS NORTHERN MA AND SOUTHWEST NH ENDS
DURING THE EARLY EVENING WITH A DRYING TREND DEVELOPING. PULSE OF
PRES RISES AND COLD AIR ADVECTION ON THE BACK SIDE WILL RESULT IN
BLUSTERY CONDITIONS OVERNIGHT. SHOULD BE ENOUGH OF A WESTERLY WIND
TO DRY THE LOW LEVELS TO PRECLUDE WIDESPREAD BLACK ICE. ALTHOUGH
CAN/T COMPLETELY RULE OUT SOME PATCHY ICE.
SUNDAY...
LOW AMPLITUDE MID LEVEL TROUGH RACES ACROSS THE AREA. WEAK FORCING
AND LACK OF DEEP LAYER MOISTURE SHOULD LIMIT ANY SNOW SHOWER
ACTIVITY TO SCATTERED IN AREAL COVERAGE. BLUSTERY AND COOLER. HIGHS
IN THE 30S BUT WIND CHILLS IN THE 20S.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
HEADLINES...
* CHANCE FOR LIGHT SNOW SHOWERS ACROSS THE INTERIOR EARLY SUNDAY
NIGHT
* GENERALLY DRY CONDITIONS EXCEPT FOR SOME OCEAN EFFECT SNOW SHOWERS
ACROSS MID AND OUTER CAPE COD AND NANTUCKET TUESDAY AND TUESDAY
NIGHT
* TEMPERATURES CONTINUE TO TURN COLDER THROUGH LATE NEXT WEEK
OVERVIEW AND MODEL PREFERENCES...
OVERALL...UPPER LEVEL PATTERN ACROSS NORTH AMERICA REMAINS THE
SAME WITH HIGHLY AMPLIFIED RIDGE ACROSS THE WESTERN U.S. WITH
AMPLIFYING TROUGH ACROSS THE EAST. MODELS REMAIN IN GOOD AGREEMENT
WITH THIS ASPECT. IN THE LONG RANGE...MODELS SHOWING A STRONG
SIGNAL OF ANOTHER ARCTIC BLAST WORKING OUT OF CENTRAL CANADA
ACROSS THE NORTH CENTRAL U.S. THROUGH THE GREAT LAKES INTO THE
NORTHEAST BEGINNING AROUND THE MONDAY TIMEFRAME THROUGH NEXT WEEK.
WEAK SHORT WAVES MOVE ACROSS THE REGION BUT...WITH THE GENERAL
W-NW SURFACE AND UPPER FLOW...LOOKS LIKE SYSTEMS WILL MOVE THROUGH
MAINLY DRY THOUGH MAY SEE A FEW SNOW SHOWERS ACROSS THE HIGHER
TERRAIN. WITH EACH SHORT WAVE...REINFORCING ARCTIC AIRMASS MOVES
IN...WITH THE COLDEST NOTED DURING THE WED-THU TIMEFRAME. CURRENT
FORECAST SUGGESTS OVERNIGHT LOWS DROPPING BELOW ZERO ACROSS THE
INTERIOR.
WITH RATHER GOOD CONSISTENCY AMONG THE MODEL SUITE...USED A BLEND OF
THE GFS AND ECMWF ALONG WITH THEIR ENSEMBLES.
DETAILS...
SUNDAY NIGHT THROUGH MONDAY NIGHT...SHORT WAVE MOVES ACROSS SUN
NIGHT INTO EARLY MONDAY WITH LEFTOVER SNOW SHOWERS ACROSS THE
INTERIOR. WINDS SHIFT TO NW AND H85 TEMPS DROP TO -7C TO -12C BY
12Z MON. A DRY SHORT WAVE MOVES ACROSS MON NIGHT WITH ANOTHER WAVE
OF ARCTIC AIR MOVING IN. H85 TEMPS DROP MON NIGHT TO -11C TO -18C
BY EARLY TUE MORNING. EXPECT OVERNIGHT LOWS MON NIGHT DOWN TO THE
SINGLE DIGITS WELL INLAND AND OVER THE HIGHER TERRAIN TO THE LOWER
20S ON OUTER CAPE COD AND NANTUCKET.
TUESDAY THROUGH WEDNESDAY NIGHT...GENERALLY DRY BUT FRIGID
CONDITIONS EXPECTED. WITH WINDS VEERING TO N-NW...CAN SEE SCT
OCEAN EFFECT SNOW SHOWERS POSSIBLY MOVING ACROSS THE MID AND OUTER
CAPE AS WELL AS NANTUCKET THROUGH TUE NIGHT. BIG QUESTION WILL BE
HOW MUCH OF A NORTHERLY COMPONENT TO THE WIND THERE WILL BE TO
ALLOW FOR SNOW SHOWERS TO MAKE IT IN. H85 TEMPS CONTINUE TO
DROP...AS LOW AS -17C TO -20C ACROSS THE REGION LATE WED NIGHT.
EXPECT LOWS WED NIGHT RANGING FROM ZERO TO 5 BELOW ACROSS S NH AND
N MA TO THE MID TEENS ON THE OUTER CAPE AND ISLANDS. THIS WILL
COMBINE WITH NW WINDS UP TO 10 MPH TO BRING BITTERLY COLD WIND
CHILLS. WILL MONITOR FOR POSSIBLE WIND CHILL ADVISORIES ACROSS
PORTIONS OF THE INTERIOR.
THURSDAY-FRIDAY...MAY SEE A CLIPPER SYSTEM WORK INTO THE REGION
DURING THURSDAY BUT WILL BE MOISTURE STARVED SO EXPECTING ONLY
WIDELY SCT SNOW SHOWERS AS IT QUICKLY MOVES THROUGH. LARGE HIGH
PRES WILL BUILD IN FOR THU NIGHT AND FRI. TEMPS FORECAST TO REMAIN
WELL BELOW SEASONAL NORMALS. MAY NEED WIND CHILL ADVISORIES ON THU
NIGHT.
&&
.AVIATION /16Z SATURDAY THROUGH WEDNESDAY/...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH SUNDAY/...
TODAY...
VFR/MVFR TO START BUT QUICKLY LOWERING TO MVFR-IFR BY 16Z-18Z.
HEAVIEST PRECIP ALONG WITH LOWEST CIGS/VSBYS WILL BE FROM 16Z-21Z
ACROSS RI/EASTERN MA INTO SOUTHERN NH. LOW PROB OF A FEW HOURS OF
LIFR OVER E MA. MAINLY ALL SNOW INTERIOR ESPECIALLY HIGHER
TERRAIN /KORH AND KMHT/ WITH A MIX OF RAIN/SNOW ELSEWHERE. AN INCH
OR TWO OF SNOW ACCUMULATION LIKELY WELL INLAND ESPECIALLY FROM
KORH TO KMHT. HOWEVER LOW RISK FOR A NARROW SWATH OF 3 TO 4 INCHES
IN THIS REGION IF PRECIP REMAINS MAINLY SNOW. CONFIDENCE LOW ON
EXACT POSITION AND EVOLUTION OF RAIN-SNOW LINE.
TONIGHT...
IMPROVING CONDITIONS WITH MVFR TO START AND VFR AFTER 06Z. ANY
LINGERING SNOW IN SOUTHERN NH WILL END 03Z-06Z. MODERATE TO HIGH
CONFIDENCE. MODEST WNW WIND DEVELOPS.
SUNDAY...
MARGINAL VFR/MVFR IN SCATTERED SNOW SHOWERS. NO ACCUMULATION
EXPECTED. GUSTY WNW WIND.
KBOS TERMINAL...MODERATE CONFIDENCE IN TAF. A MIX OF RAIN AND SNOW
EXPECTED. HOWEVER SURFACE TEMPS SHOULD BE WARM ENOUGH TO PRECLUDE
MUCH IF ANY ACCUMULATION. HEAVIEST PRECIP 16Z-20Z.
KBDL TERMINAL...MODERATE CONFIDENCE IN TAF. STEADIEST PRECIP
12Z-18Z THEN TAPERING OFF.
.AVIATION /10Z SATURDAY THROUGH WEDNESDAY/...
OUTLOOK...SUNDAY NIGHT THROUGH WEDNESDAY...MODERATE CONFIDENCE.
SUNDAY NIGHT AND MONDAY...VFR. PATCHY MVFR CIGS/VSBYS IN ANY SNOW
SHOWERS MAINLY ACROSS THE INTERIOR...THEN ON MONDAY ACROSS CAPE
COD AND THE ISLANDS. SW WINDS GUSTING UP TO 20-25 KT EARLY SUN
NIGHT THEN SHIFT TO W AND DIMINISHING.
MONDAY NIGHT...MAINLY VFR. NW WIND GUSTS UP TO 20 KT ON THE MID
AND OUTER CAPE AS WELL AS NANTUCKET.
TUESDAY THROUGH WEDNESDAY...VFR. LOCAL MVFR CONDITIONS ACROSS
OUTER CAPE COD AND NANTUCKET WITH ANY OCEAN EFFECT SNOW SHOWERS
TUESDAY INTO EARLY TUESDAY NIGHT. BREEZY N-NW WINDS WITH GUSTS UP
TO 25 KT ALONG THE COAST.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
MODERATE TO HIGH FORECAST CONFIDENCE THROUGH SUNDAY.
TODAY...
BROAD AREA OF LOW DEVELOPS OVER NEW ENGLAND AND THE NEARBY
WATERS. RAIN AND SNOW REDUCES VSBY. LIGHT WINDS GIVEN WEAK LOW
PRES PASSING OVERHEAD.
TONIGHT...
STRENGTHENING LOW OVER GEORGES BANK RACES NE INTO THE MARITIMES.
MODEST WNW WINDS 15-20 KT GUSTS UP TO 25 KT POSSIBLE. ANY
SNOW/RAIN ENDS EARLY WITH IMPROVING VSBY.
SUNDAY...
WSW WINDS 15-25 KT. SCATTERED SNOW SHOWERS POSSIBLE. GOOD VSBY.
OUTLOOK...SUNDAY NIGHT THROUGH WEDNESDAY...MODERATE CONFIDENCE.
SUNDAY NIGHT...W GALES LIKELY WITH GUSTS UP TO 35-40 KTS OVER THE
OPEN WATERS. SEAS BUILDING UP TO 10-12 FEET.
MONDAY...LEFTOVER W GALE GUSTS EARLY. GUSTS WILL CONTINUE AT 25-30
KT...HIGHEST ON THE OUTER WATERS. ARCTIC FRONT CROSSES THE WATERS
WITH OCEAN EFFECT SNOW SHOWERS DEVELOPING MON NIGHT. WINDS SHIFT TO
NW AND DIMINISH WITH SEAS SLOWLY SUBSIDING.
MONDAY NIGHT THROUGH WEDNESDAY...NW WINDS WILL OCCASIONALLY GUST UP
TO 25 KT. SEAS AROUND 5 FT MAINLY ON THE OUTER WATERS WITH A CHANCE
OF LIGHT FREEZING SPRAY. OCEAN EFFECT LOW CLOUDS AND SNOW WILL CAUSE
VSBY RESTRICTIONS.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR
MAZ002>004-008-010-026.
NH...WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR NHZ011-
012-015.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 6 PM THIS EVENING TO 6 AM EST SUNDAY
FOR ANZ231>234.
SMALL CRAFT ADVISORY UNTIL 6 AM EST SUNDAY FOR ANZ237.
SMALL CRAFT ADVISORY UNTIL 6 AM EST SUNDAY FOR ANZ235-250-
254>256.
&&
$$
SYNOPSIS...NOCERA/EVT
NEAR TERM...NOCERA/DUNTEN
SHORT TERM...NOCERA
LONG TERM...EVT
AVIATION...NOCERA/EVT
MARINE...NOCERA/EVT
AREA FORECAST DISCUSSION
NWS GRAY ME
1103 AM EST SAT JAN 18 2014
.SYNOPSIS...
LOW PRESSURE WILL DEVELOP OFF THE SOUTHERN NEW ENGLAND COASTLINE
TODAY...ALLOWING FOR ACCUMULATING SNOWFALL. THE SNOW WILL TAPER TO
SCATTERED SNOW SHOWERS TONIGHT. AN UPPER LEVEL TROUGH WILL CROSS THE REGION
SUNDAY...FOLLOWED BY AN ARCTIC FRONT EARLY MONDAY MORNING.
THEREAFTER...VERY COLD AND DRY WEATHER IS EXPECTED THROUGH MUCH OF
THE WEEK. THE EXCEPTION WILL BE THE MOUNTAINS WHERE UPSLOPE SNOW
SHOWERS WILL OCCUR.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
1045 AM UPDATE...HAVE MADE SOME MINOR ADJUSTMENTS TO THE PREVIOUS
FORECAST BASED ON LATEST TRENDS IN OBSERVATIONS...RADAR/SAT
IMAGERY...AND LATEST MESOSCALE MODEL DATA. OVERALL...THE GOING
FORECAST IS LARGELY SUPPORTED BY THE LATEST DATA.
THE MAIN QUESTION REMAINS WHETHER OR NOT A HEAVY BAND OF
PRECIPITATION WILL MOVE NORTHWARD UP THE COASTAL PLAIN OF NH AND
ME THIS AFTERNOON AND EVENING AND WHAT WILL THE P-TYPE BE. THE
HRRR HAS BEEN WAFFLING AROUND A BIT WITH RESPECT TO THE
POSITIONING OF THE RELATIVELY NARROW BAND OF FORCING ASSOCIATED
WITH STRONG PRESSURE FALLS AND MID LEVEL FRONTOGENESIS. WOULD LIKE
TO SEE A LITTLE MORE CONSISTENCY THERE.
THE LATEST RUN OR TWO OF THE RAP SEEMS TO BE CORRESPONDING BETTER
TO THE BLOSSOMING BAND OF PRECIPITATION ACROSS EASTERN
MASSACHUSETTS...WHICH AT LEAST FOR THE TIME BEING...IS MOVING
NEARLY DUE NORTH. HAVE CONTINUED TO LEND MORE CREDENCE TO THE
LATEST RAP AS A RESULT.
A LITTLE LIGHT RAIN AT THE START SHOULD TRANSITION TO A HEAVY WET
SNOW ONCE THE STRONG UVV/S ARRIVE IN A FEW HOURS. FORECAST SNOW
AMOUNTS HAVE BEEN ADJUSTED A BIT...MAINLY TO ALLOW FOR A MORE
NARROW BAND OF HEAVIER SNOWFALL ON THE COASTAL PLAIN.
HOWEVER...THIS REMAINS A VERY FLUID SITUATION WITH LOW TO MODERATE
CONFIDENCE.
ISOLD THUNDER WILL BE POSSIBLE IN THE HEAVIEST BAND OF
PRECIPITATION...AS WE HAVE SEEN JUST SOUTH OF BOSTON.
PREVIOUS DISCUSSION...
UPDATE...MINOR CHANGES TO ACCOUNT FOR LATEST OBSERVATIONAL
TRENDS...MAINLY TO DELAY LIKELY POP SLIGHTLY BY AN HOUR OR SO.
NOTED IS DEVELOPING BAROCLINIC LEAF OFF THE MID ATLANTIC. WITHIN
IT EXPANDING...COOLING CLOUD TOPS AND LIGHTNING ARE BEING OBSERVED
OFF THE COAST. SOME LIGHT PCPN IS WORKING NWD THRU MA ATTM...WITH
TEMPS BELOW FREEZING IN SRN NH THIS SHOULD BE ALL SN. A MORE
WIDESPREAD SNFL CONTINUES TO DEVELOP WITHIN THE WARM CONVEYOR BELT
NW OF KNYC THRU KBUF. THIS WILL WORK E AND FILL IN WITH TIME.
PREVIOUS DISCUSSION...S/WV TROF NEARING THE EAST COAST THIS
MORNING IS ALREADY AIDING IN THE DEVELOPMENT OF WEAK LOW PRES
INVOF DELMARVA. THIS LOW PRES IS FORECAST TO TRACK NEWD TOWARDS
SRN NEW ENGLAND. ADDITIONAL S/WV ENERGY WILL HANG BACK ACROSS THE
ERN GREAT LAKES. BETWEEN THE TWO FEATURES A SFC TROF IS EXPECTED
TO DEVELOP...THIS BEING THE FORECAST PROBLEM OF THE DAY.
AS IT STANDS NOW PCPN IS ALREADY BREAKING OUT TO THE N OF THE SFC
LOW. THIS WILL GRADUALLY EXPAND NWD WITH TIME...REACHING SRN ZONES
THIS MORNING..AND THE NRN HALF OF THE CWFA BY THIS AFTERNOON. AS
LOW PRES DEEPENS NE OF CAPE COD...INVERTED SFC TROF WILL SERVE TO
FOCUS AND ENHANCE QPF. ECMWF AND GFS HAVE BEEN RELATIVELY
CONSISTENT WITH BETWEEN 0.50 AND 0.75 INCHES QPF FOR COASTAL
PORTIONS OF SRN NH AND SWRN ME. NAM HAS WAFFLED A BIT...WITH ONE
RUN BEING DRY AND THE NEXT INCREASING QPF CLOSER TO THE GLOBAL
SOLUTIONS. OPTED TO TAKE A BLEND OF THE THREE MODELS...WITH HPC
AND RFC GUIDANCE AS WELL.
NEXT ISSUE IS SFC TEMPS. FOR THE LAST COUPLE OF DAYS MODEL
GUIDANCE HAS BEEN INSISTENT ON THE BOUNDARY LAYER WARMING ABOVE
FREEZING FOR PART OF IF NOT MOST OF THE DAY. HOWEVER...ATTM DEW
POINTS ARE THE LOW TO MID 20S...WITH WIDESPREAD TEMPS IN THE 20S.
AS PCPN BEGINS...WET BULB COOLING SHOULD SERVE TO LOCK MUCH OF THE
INTERIOR BELOW FREEZING. ELY FLOW DEVELOPING AT OR JUST ABOVE SFC
WILL TRY AND BRING IN SOME MILDER AIR...ESPECIALLY NEAR THE COAST
AND PENOBSCOT BAY. HOWEVER...IT IS BEGINNING TO LOOK LIKE A
MAJORITY SN EVENT FOR THE AREA.
DESPITE MARGINAL SFC TEMPS...SNOW GROWTH ZONE IS WELL ALIGNED
WITH THE GREATEST LIFT...AND SEE NO REASON WHY RATIOS WON/T BE A
LITTLE BETTER THAN 10 TO 1. GIVEN THE TEMPS AND QPF...SNFL AMOUNT
ARE A GENERAL 2 TO 4 INCHES S OF THE MTNS...WITH A POCKET OF 4 TO
6 INCHES BOUNDED BY KCON...KLCI...AND KPWM. IT IS THIS AREA THAT
THE MAJORITY OF MODEL GUIDANCE FAVORS FOR THE PLACEMENT OF SFC
TROF. WITHIN THIS AREA IT WOULD NOT BE SURPRISING TO SEE A NARROW
BAND OF 6 PLUS INCH AMOUNTS. HOWEVER THESE INVERTED TROF FEATURES
ARE VERY DIFFICULT TO PINPOINT UNTIL THEY ARE SETTING UP. FOR NOW
WILL ISSUE WINTER WX ADVISORIES FOR SRN NH AND COASTAL ME...WITH
STRONGER WORDING ACROSS EXTREME SERN NH AND SWRN ME. ONCE THE TROF
SETS UP AND IF IT LOOKS LIKE THERE IS A SIGNIFICANT ENHANCEMENT OF
PCPN OCCURRING...THE NEXT SHIFTS COULD CONSIDER A SMALL AREA
UPGRADE TO WARNINGS.
EXPECT THAT STRONG LIFT AND LOW STATIC STABILITY ALOFT WILL LEAD
TO CONVECTIVE ELEMENTS WITHIN THE OVERALL PCPN SHIELD. THIS WILL
RESULT IN AREAS OF +SN AT TIMES...ESPECIALLY CLOSER TO THE SFC LOW
AND STRONGEST LIFT. IN FACT SOME MODELS INDICATE UNSTABLE
CONDITIONS ALOFT...AND IF LIFT IS STRONG ENOUGH A RUMBLE OF
THUNDER AROUND NEW ENGLAND CANNOT BE RULED OUT.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
SNFL WILL TAPER OFF THIS EVENING...BUT STEADIER PCPN WILL LINGER
WITHIN SFC TROF. THIS IS MOST LIKELY TO BE ALIGNED NEAR THE
COAST...AND BACK INTO SRN NH. THIS IS WHERE HIGHEST POP WILL
REMAIN THRU THE NIGHT.
CYCLONIC FLOW WILL CONTINUE INTO SUN...AHEAD OF APPROACHING ARCTIC
BOUNDARY. EXPECT THAT SCT SHSN WILL BE POSSIBLE THRU MUCH OF THE
DAY...BECOMING MORE WIDESPREAD AS FNT NEARS...ESPECIALLY FOR THE
HIGHER TERRAIN.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
YET ANOTHER ARCTIC FRONT WILL CROSS THE REGION DURING THE EARLY
MORNING HOURS ON MONDAY. WINDS WILL BE GUSTY BOTH AHEAD OF AND
BEHIND THIS FEATURE. SUFFICIENT INSTABILITY AND MOISTURE TO ALLOW
FOR A BRIEF PASSING SNOW SQUALL IN MANY AREAS AS WELL AS THE COLD
AIR BLASTS INTO THE REGION.
A PERIOD OF LIGHT SNOW MAY LINGER INTO THE EARLY AFTERNOON HOURS
AS WELL AS THE 00Z MODEL SUITE CONTINUES TO SHOW A WEAK WAVE
FORMING ALONG THE ARCTIC BOUNDARY.
TEMPERATURES REMAIN RELATIVELY STEADY ON MONDAY. HOWEVER...BY
MONDAY NIGHT...MUCH OF THE REGION WILL BE BELOW ZERO...WITH THE
EXCEPTION POSSIBLY THE COASTLINE.
NEW EURO ATTEMPTS TO DEVELOP A STRONG COASTL LOW OFF THE SOUTHERN
NEW ENGLAND COASTLINE THURSDAY INTO THURSDAY NIGHT. LATEST GFS
ENSEMBLE MEAN HINTING AT THIS POSSIBILITY AS WELL...HOWEVER THIS
MODEL IS MORE PROGRESSIVE. WILL AWAIT ANOTHER MODEL RUN...AND IF
STILL PRESENT...THIS WILL REQUIRE BOOSTING POPS FOR LATER IN THE
WORK WEEK.
&&
.AVIATION /16Z SATURDAY THROUGH WEDNESDAY/...
SHORT TERM....SNFL MIXED WITH RAIN/SLEET AT TIMES WILL THEN BEGIN
SPREADING INTO THE AREA FROM S TO N. IFR OR LOWER CONDITIONS ARE
POSSIBLE THRU THE DAY...ESPECIALLY NEAR THE COAST AND S OF KAUG.
SN WILL TAPER OFF TONIGHT...BUT SCT SHSN WILL LINGER INTO SUN.
LONG TERM...CONDITIONS POSSIBLY BRIEFLY DROPPING TO LIFR IN ANY
SCATTERED SNOW SQUALLS WITH THE PASSAGE OF THE ARCTIC FRONT EARLY
MONDAY MORNING. OTHERWISE...MAINLY VFR CONDITIONS OUTSIDE THE
MOUNTAINS.
&&
.MARINE...
SHORT TERM...SEAS AOA 5 FT WILL CONTINUE FOR THE BETTER PART OF
THE DAY TODAY. SEAS BUILD AGAIN SUN AS COLD FNT APPROACHES THE
WATERS...WITH WIND GUSTS INCREASING TO 25-30 KTS.
LONG TERM...SCA CONDITIONS EXPECTED SUNDAY NIGHT INTO EARLY MONDAY
MORNING AHEAD OF AND BEHIND THE ARCTIC FRONT. GALE FORCE WINDS ARE
POSSIBLE AS WELL WITH THIS EVENT. THEREAFTER...A GUSTY WNW FLOW
WILL BRING SCA CONDITIONS FOR MUCH OF THE UPCOMING WORK WEEK.
&&
.HYDROLOGY...
AN ICE JAM IS STILL CAUSING HIGH WATER ON THE
KENNEBEC NEAR NORTH SIDNEY. THE WATER LEVEL HAS BEEN DECREASING
DURING THE EARLY MORNING HOURS AND IT CURRENTLY REMAINS BELOW
FLOOD STAGE. THE ICE JAMS REMAIN HIGHLY UNPREDICTABLE...WITH RAPID
FLUCTUATIONS IN WATER LEVELS OVER SHORT PERIODS OF TIME. ICE JAMS
ARE ALSO POSSIBLE ON OTHER RIVERS ACROSS THE REGION AND PEOPLE
LIVING ALONG STREAMS AND RIVERS SHOULD MONITOR WATER LEVELS
CLOSELY...ESPECIALLY AS THE RETURN OF COLD WEATHER CAUSES ICE TO
BUILD BACK UP.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR MEZ018-
019-023-024.
WINTER WEATHER ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR
MEZ025>028.
NH...WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR
NHZ005>010-013-014.
MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL MIDNIGHT EST
TONIGHT FOR ANZ150-152-154.
&&
$$
NEAR TERM UPDATE...EKSTER
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
919 AM EST SAT JAN 18 2014
.SYNOPSIS...
THE COMBINATION OF A WEAKENING UPPER DISTURBANCE AND A DEVELOPING
AREA OF LOW PRESSURE OFF THE NEW JERSEY COAST WILL BRING LIGHT
SNOW TO PORTIONS OF THE NORTH COUNTRY TODAY BEFORE TAPERING OFF
TONIGHT. MORE SNOW SHOWERS AND POSSIBLE SNOW SQUALLS ARE EXPECTED
ON SUNDAY AHEAD OF AN ARCTIC COLD FRONT...WHICH WILL MOVE THROUGH
THE REGION SUNDAY NIGHT THROUGH EARLY MONDAY. BITTERLY COLD AIR
WILL FOLLOW THE FRONT FOR ALL OF NEXT WEEK...WITH HIGHS IN THE
SINGLE DIGITS TO LOW TEENS ABOVE ZERO...AND LOWS IN THE SINGLE
DIGITS TO TEENS BELOW.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 905 AM EST SATURDAY...AS STATED BY PREVIOUS FORECASTER THE
CHALLENGE TODAY AND TONIGHT WL BE AREAL COVERAGE/INTENSITY OF
SNOW ASSOCIATED WITH POTENT 5H ENERGY IN THE FLW ALOFT.
UNFORTUNATELY IF YOU ARE LOOKING FOR SNOW TODAY...IT LOOKS LIKE
OUR CWA WL BE SPLIT BTWN TWO SYSTEMS AND STAY MOSTLY
DRY...ESPECIALLY NORTHERN CPV. WATER VAPOR SHOWS 1ST POTENT 5H VORT
WITH ENHANCED COOLING ON IR SATL PIC ACRS WESTERN/CENTRAL NY WITH ANOTHER
IMPRESSIVE 5H VORT LOCATED ACRS CENTRAL NJ THIS MORNING. THE
WESTERN ENERGY AND ENHANCED MID LVL MOISTURE/LIFT WL TRACK FROM
BGM TO SYR TO MSS THIS AFTN...WITH SOME LIGHT SNOW LIKELY ACRS THE
SLV/WESTERN DACKS. CRNT FCST HAS THIS COVERED VERY WELL WITH
LIKELY POPS AND DUSTING TO 2 INCHES. MEANWHILE...2ND VORT WITH
LIGHTNING NOTED ACRS CENTRAL NJ AND SOUTH OF LONG ISLAND WL RACE
NE AND CLIP EASTERN NEW ENGLAND WITH PRECIP. MEANWHILE...OUR CWA
SITS BTWN THESE TWO SYSTEMS WITH LATEST 12Z RAP AND 12Z NAM
SHOWING A RIBBON OF ENHANCED 850 TO 500MB MOISTURE AND 700 TO 500
UVVS FIELDS LOCATED OVER EASTERN NY/WESTERN NEW ENGLAND THIS
MORNING...WEAKENING AS IT LIFTS TWD OUR CWA THIS AFTN/EVENING.
RADAR DOES SHOW WIDESPREAD LIGHT SNOW ASSOCIATED WITH THESE
FEATURES ATTM...AND WL MONITOR TRENDS FOR POSSIBLE IMPACTS ACRS
OUR CENTRAL/SOUTHERN CWA AFT 16Z TODAY...BUT CRNT FCST HAS LIKELY
POPS ACRS RUTLAND/WINDSOR/ORANGE COUNTIES WHICH LOOKS GOOD. WL
WATCH FOR POSSIBLE EXPANSION NORTH THRU THE AFTN BASED ON CRNT
RADAR TRENDS.
OTHERWISE...NEXT POTENT 5H VORT LOCATED ACRS THE WESTERN GREAT
LAKES IMPACTS OUR CWA TONIGHT. ONCE AGAIN LIMITED MOISTURE BUT
GOOD DYNAMICS. MAY NEED TO BUMP POPS UP SLIGHTLY IN A FEW
LOCATIONS...BUT WL EXAMINE 12Z DATA COMPLETELY BEFORE FINAL
DECISION. TEMPS ARE ALL OVER THE PLACE THIS MORNING...BUT SHOULD
RANGE IN THE MID/UPPER 20S MTNS TO L/M 30S VALLEYS. CLOUDS/PRECIP
THIS AFTN WL IMPACT HIGHS ACRS THE SLV AND SOUTHERN VT ZNS.
AS HAS BEEN THE CASE OVER THE LAST FEW DAYS...LATEST RUC/RAP AND
LOCAL 6KM WRF (ALSO RUC BASED) HAVE HANDLED THE FIRST 18 HOURS OF
THE FORECAST VERY WELL DUE TO INITIALIZATION INCLUDING LATEST
SATELLITE AND RADAR DATA...AND THE SAME GOES FOR TODAY. THUS HAVE
LEANED ON THEM HEAVILY FOR THE NEAR TERM FORECAST. OVERALL SYNOPTIC
SETUP FEATURES A WEAKENING MID-LEVEL SHORTWAVE OVER THE OHIO
RIVER VALLEY THIS MORNING...WHILE SURFACE LOW PRESSURE IS
BEGINNING TO DEVELOP OFF THE NJ COAST. AS BOTH OF THESE FEATURES
SHIFT NORTH/NORTHEAST THE BTV CWA IS BASICALLY SQUEEZED BETWEEN
THE 2 SYSTEMS WITH MOISTURE TO OUR SOUTHWEST AND SOUTHEAST AND
GENERALLY DRY SURFACE TO MID-LEVEL AIR IN-BETWEEN AS IS EVIDENT
BY CURRENT CLEAR SKIES ON REGIONAL IR. PRECIP ASSOCIATED WITH THESE
FEATURE DOES FILTER INTO PORTIONS OF THE FORECAST AREA TODAY
THOUGH...MAINLY ACROSS THE ST. LAWRENCE VALLEY AND SOUTHEASTERN
VERMONT DURING THE MID-MORNING HOURS...BUT AREAS IN-BETWEEN WILL
LIKELY SEE LITTLE THROUGH THE DAY UNDER PARTLY TO MOSTLY CLOUDY
SKIES. WHERE PRECIP DOES FALL...IT`LL BE IN THE FORM OF SNOW AND
WE`LL SEE SOME LIGHT ACCUMULATIONS OF GENERALLY 1-3". HIGHS TODAY
WILL REMAIN ON THE MILD SIDE OF NORMAL...WARMEST WHERE MORE
SUNSHINE WILL BE POSSIBLE IN THE CHAMPLAIN VALLEY AND NORTHERN
VERMONT...GENERALLY LOWER TO MID 30S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/...
AS OF 356 AM EST SATURDAY...FOR TONIGHT...AFOREMENTIONED
SHORTWAVE AND COASTAL LOW SHIFT NORTHWARD ENOUGH TO SPILL SOME
MOISTURE INTO CENTRAL PORTIONS OF THE FORECAST AREA BUT BY THAT
TIME THE DEEPEST MOISTURE IS OFFSHORE AND TO OUR NORTHWEST SO
HAVE ONLY OFFERED CHANCE POPS WITH A DUSTING TO POSSIBLY AN INCH
OF ADDITIONAL ACCUMULATION ACROSS THE ENTIRE AREA. BEST CHANCE FOR
SNOW SHOWERS TONIGHT WILL BE DOWNWIND OF LAKE ONTARIO AS SURFACE
AND MID-LEVEL FLOW TURNS SOUTHWESTERLY AFTER MIDNIGHT ALLOWING FOR
FOR ENHANCED LAKE EFFECT. UNDER CLOUDY SKIES OVERNIGHT LOWS REMAIN
MILD IN THE TEENS TO MID 20S.
ACTIVE WEATHER CONTINUES GOING INTO SUNDAY AS THE NORTH COUNTRY
WILL BE IMPACTED BY YET ANOTHER SHORTWAVE ROUNDING THE BASE OF THE
PERSISTENT BROAD UPPER TROUGH OVER THE EASTERN CONUS. IT`S
CURRENTLY MOVING THROUGH THE DAKOTAS THIS MORNING AND WILL TRACK
THROUGH THE OHIO RIVER VALLEY TONIGHT AND INTO THE MID-ATLANTIC
STATES SUNDAY. MEANWHILE TO OUR NORTHWEST...AN ARCTIC COLD FRONT
APPROACHES THE REGION AND THE COMBINATION OF THESE 2 FEATURES WILL
RENEW CHANCES FOR SNOW SHOWERS AND POSSIBLE SNOW SQUALLS SUNDAY
AFTERNOON AND EVENING BEFORE TAPERING OFF AFTER MIDNIGHT. ANOTHER
ROUND OF ACCUMULATING SNOW IS LIKELY ACROSS THE ENTIRE AREA WITH
AMOUNT GENERALLY 1-3" AGAIN...THOUGH COULD SEE SOME HIGHER AMOUNTS
ACROSS THE NORTHERN GREENS THROUGH SUNDAY NIGHT.
WE REMAIN UNDER THE INFLUENCE OF BROAD UPPER TROUGHINESS FOR
MONDAY AS WELL THOUGH FLOW IS GENERALLY WESTERLY AND DRIER WITH
JUST SOME CHANCE POPS ACROSS THE HIGHER TERRAIN FOR LIGHT SNOW
SHOWERS. MONDAY WILL MARK THE FIRST DAY IN AWHILE THOUGH THAT
WE`LL GO BELOW NORMAL FOR TEMPS WITH EXPECTED HIGHS ONLY IN THE
SINGLE NUMBERS TO TEENS. COLDER AIR MOVES IN FOR MONDAY NIGHT
ONWARD AS THE ARCTIC FRONT DROPS THROUGH THE REGION...MORE ON THAT
BELOW.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
AS OF 215 AM EST SATURDAY...QUIET...ALBEIT VERY COLD WEATHER ON
TAP FOR THE MIDDLE AND LATER PORTIONS OF NEXT WEEK WITH 00Z MODELS
REMAINING IN GOOD AGREEMENT SHOWING A PRONOUNCED RETURN OF ARCTIC
AIR TO THE NERN QUARTER OF THE NATION AND REMINDING US ALL THAT
IT`S STILL JANUARY. WE`RE NOT TALKING RECORD COLD BY ANY
MEANS...AND LOOKING AT RECENT TRENDS IN THE GUIDANCE THE COMING
COLD SNAP WILL LIKELY BE JUST A TAD MILDER THAN IT`S COUNTERPART
EARLIER THIS MONTH IF ANY SOLACE CAN BE TAKEN. THAT SAID IT WON`T
BE THAT PLEASANT AS DAYTIME HIGHS RANGE FROM -5F TO +5F TUE/WED
AND MODERATING ONLY VERY SLOWLY THU/FRI BY ABOUT 5 DEG EACH DAY.
LOWS GENERALLY IN THE -5F TO -15F RANGE MON NT/WED NT/THU NT WITH
COLDEST NIGHT LIKELY TUESDAY NIGHT WHEN VALUES SHOULD BOTTOM OUT
FROM 10 TO 20 BELOW. IN TERMS OF SENSIBLE WEATHER A PRETTY BORING
PATTERN HOWEVER. OUTSIDE SOME POSSIBLE WIND CHILL ISSUES MONDAY
NIGHT...NOT MUCH TO TALK ABOUT OTHER THAN THE COLD AS ARCTIC HIGH
PRESSURE MAINTAINS BROAD SYNOPTIC SCALE SUBSIDENCE AND DRY WEATHER
ACROSS THE AREA. BY FRIDAY NIGHT/SATURDAY...SOME HINTS AT A WEAK
NRN STREAM CLIPPER LOW POSSIBLY SPARKING SOME WARM ADVECTION-
DRIVEN LIGHT SNOWS/SHSN ACROSS THE AREA BUT NOTHING MORE THAN
TOKEN 30/40 POPS AT THIS POINT GIVEN WE`RE TALKING 7 DAYS OUT.
&&
.AVIATION /14Z SATURDAY THROUGH WEDNESDAY/...
THROUGH 12Z SUNDAY...MAINLY VFR CONDS EXPECTED THROUGH 18Z UNDER
LIGHT FLOW LESS THAN 10 KTS. SOME BKN/OVC VFR CIGS DURING THIS
PERIOD...BUT GENERALLY AT 060 AGL AND ABOVE. AFTER 18Z BKN/OVC
CIGS GRADUALLY LOWER WITH PERIODS OF MVFR AND/OR IFR LIGHT SNOW
POSSIBLE...ESP AT KMPV/KRUT AND KMSS. WINDS LIGHT...THOUGH
TRENDING NORTH TO NORTHEASTERLY THROUGH TIME. AREAS OF LIGHT SNOW
TAPER OFF TONIGHT LEAVING BKN/OVC VFR/MVFR CONDS WITH PATCHY BR
HERE AND THERE IN THE 3-6SM RANGE. WINDS LIGHT.
OUTLOOK 12Z SUNDAY THROUGH WEDNESDAY...
12Z SUN THROUGH 12Z MONDAY...VFR WITH SCT MVFR/IFR IN SHSN AS
ARCTIC FRONT PUSHES THROUGH THE AREA. BEST SHSN COVERAGE 18-06Z.
12Z MONDAY ONWARD...MAINLY VFR WITH HIGH PRESSURE.
&&
.EQUIPMENT...
AS OF 400 AM EST SATURDAY...THE KTYX 88D DOPPLER RADAR LOCATED IN
NORTHERN NEW YORK REMAINS OUT OF SERVICE DUE TO A FAILED POWER
SUPPLY. PARTS ARE ON ORDER TO REPAIR THE PROBLEM BUT IT WILL
LIKELY BE OUT OF SERVICE THROUGH AT LEAST TUESDAY JANUARY 21.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...LAHIFF
NEAR TERM...LAHIFF/TABER
SHORT TERM...LAHIFF
LONG TERM...JMG
AVIATION...JMG
EQUIPMENT...WFO BTV
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
613 AM EST SAT JAN 18 2014
.SYNOPSIS...
THE COMBINATION OF A WEAKENING UPPER DISTURBANCE AND A DEVELOPING
AREA OF LOW PRESSURE OFF THE NEW JERSEY COAST WILL BRING LIGHT
SNOW TO PORTIONS OF THE NORTH COUNTRY TODAY BEFORE TAPERING OFF
TONIGHT. MORE SNOW SHOWERS AND POSSIBLE SNOW SQUALLS ARE EXPECTED
ON SUNDAY AHEAD OF AN ARCTIC COLD FRONT...WHICH WILL MOVE THROUGH
THE REGION SUNDAY NIGHT THROUGH EARLY MONDAY. BITTERLY COLD AIR
WILL FOLLOW THE FRONT FOR ALL OF NEXT WEEK...WITH HIGHS IN THE
SINGLE DIGITS TO LOW TEENS ABOVE ZERO...AND LOWS IN THE SINGLE
DIGITS TO TEENS BELOW.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 400 AM EST SATURDAY...CHALLENGING FORECAST OVER THE NEXT 24
HOURS AS MODELS CONTINUE TO STRUGGLE TO RESOLVE SURFACE AND MID
LEVEL FEATURES AND THEIR ASSOCIATED MOISTURE AND LIFT. HAVE MADE
SEVERAL MODIFICATIONS FROM THE PREVIOUS FORECAST BASED ON CHANGES
IN GUIDANCE...GENERALLY OFFERING MUCH LESS SNOW (SIGH) ACROSS
MOST OF THE NORTH COUNTRY TODAY AND TONIGHT.
AS HAS BEEN THE CASE OVER THE LAST FEW DAYS...LATEST RUC/RAP AND
LOCAL 6KM WRF (ALSO RUC BASED) HAVE HANDLED THE FIRST 18 HOURS OF
THE FORECAST VERY WELL DUE TO INITIALIZATION INCLUDING LATEST
SATELLITE AND RADAR DATA...AND THE SAME GOES FOR TODAY. THUS HAVE
LEANED ON THEM HEAVILY FOR THE NEAR TERM FORECAST. OVERALL SYNOPTIC
SETUP FEATURES A WEAKENING MID-LEVEL SHORTWAVE OVER THE OHIO
RIVER VALLEY THIS MORNING...WHILE SURFACE LOW PRESSURE IS
BEGINNING TO DEVELOP OFF THE NJ COAST. AS BOTH OF THESE FEATURES
SHIFT NORTH/NORTHEAST THE BTV CWA IS BASICALLY SQUEEZED BETWEEN
THE 2 SYSTEMS WITH MOISTURE TO OUR SOUTHWEST AND SOUTHEAST AND
GENERALLY DRY SURFACE TO MID-LEVEL AIR IN-BETWEEN AS IS EVIDENT
BY CURRENT CLEAR SKIES ON REGIONAL IR. PRECIP ASSOCIATED WITH THESE
FEATURE DOES FILTER INTO PORTIONS OF THE FORECAST AREA TODAY
THOUGH...MAINLY ACROSS THE ST. LAWRENCE VALLEY AND SOUTHEASTERN
VERMONT DURING THE MID-MORNING HOURS...BUT AREAS IN-BETWEEN WILL
LIKELY SEE LITTLE THROUGH THE DAY UNDER PARTLY TO MOSTLY CLOUDY
SKIES. WHERE PRECIP DOES FALL...IT`LL BE IN THE FORM OF SNOW AND
WE`LL SEE SOME LIGHT ACCUMULATIONS OF GENERALLY 1-3". HIGHS TODAY
WILL REMAIN ON THE MILD SIDE OF NORMAL...WARMEST WHERE MORE
SUNSHINE WILL BE POSSIBLE IN THE CHAMPLAIN VALLEY AND NORTHERN
VERMONT...GENERALLY LOWER TO MID 30S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/...
AS OF 356 AM EST SATURDAY...FOR TONIGHT...AFOREMENTIONED
SHORTWAVE AND COASTAL LOW SHIFT NORTHWARD ENOUGH TO SPILL SOME
MOISTURE INTO CENTRAL PORTIONS OF THE FORECAST AREA BUT BY THAT
TIME THE DEEPEST MOISTURE IS OFFSHORE AND TO OUR NORTHWEST SO
HAVE ONLY OFFERED CHANCE POPS WITH A DUSTING TO POSSIBLY AN INCH
OF ADDITIONAL ACCUMULATION ACROSS THE ENTIRE AREA. BEST CHANCE FOR
SNOW SHOWERS TONIGHT WILL BE DOWNWIND OF LAKE ONTARIO AS SURFACE
AND MID-LEVEL FLOW TURNS SOUTHWESTERLY AFTER MIDNIGHT ALLOWING FOR
FOR ENHANCED LAKE EFFECT. UNDER CLOUDY SKIES OVERNIGHT LOWS REMAIN
MILD IN THE TEENS TO MID 20S.
ACTIVE WEATHER CONTINUES GOING INTO SUNDAY AS THE NORTH COUNTRY
WILL BE IMPACTED BY YET ANOTHER SHORTWAVE ROUNDING THE BASE OF THE
PERSISTENT BROAD UPPER TROUGH OVER THE EASTERN CONUS. IT`S
CURRENTLY MOVING THROUGH THE DAKOTAS THIS MORNING AND WILL TRACK
THROUGH THE OHIO RIVER VALLEY TONIGHT AND INTO THE MID-ATLANTIC
STATES SUNDAY. MEANWHILE TO OUR NORTHWEST...AN ARCTIC COLD FRONT
APPROACHES THE REGION AND THE COMBINATION OF THESE 2 FEATURES WILL
RENEW CHANCES FOR SNOW SHOWERS AND POSSIBLE SNOW SQUALLS SUNDAY
AFTERNOON AND EVENING BEFORE TAPERING OFF AFTER MIDNIGHT. ANOTHER
ROUND OF ACCUMULATING SNOW IS LIKELY ACROSS THE ENTIRE AREA WITH
AMOUNT GENERALLY 1-3" AGAIN...THOUGH COULD SEE SOME HIGHER AMOUNTS
ACROSS THE NORTHERN GREENS THROUGH SUNDAY NIGHT.
WE REMAIN UNDER THE INFLUENCE OF BROAD UPPER TROUGHINESS FOR
MONDAY AS WELL THOUGH FLOW IS GENERALLY WESTERLY AND DRIER WITH
JUST SOME CHANCE POPS ACROSS THE HIGHER TERRAIN FOR LIGHT SNOW
SHOWERS. MONDAY WILL MARK THE FIRST DAY IN AWHILE THOUGH THAT
WE`LL GO BELOW NORMAL FOR TEMPS WITH EXPECTED HIGHS ONLY IN THE
SINGLE NUMBERS TO TEENS. COLDER AIR MOVES IN FOR MONDAY NIGHT
ONWARD AS THE ARCTIC FRONT DROPS THROUGH THE REGION...MORE ON THAT
BELOW.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
AS OF 215 AM EST SATURDAY...QUIET...ALBEIT VERY COLD WEATHER ON
TAP FOR THE MIDDLE AND LATER PORTIONS OF NEXT WEEK WITH 00Z MODELS
REMAINING IN GOOD AGREEMENT SHOWING A PRONOUNCED RETURN OF ARCTIC
AIR TO THE NERN QUARTER OF THE NATION AND REMINDING US ALL THAT
IT`S STILL JANUARY. WE`RE NOT TALKING RECORD COLD BY ANY
MEANS...AND LOOKING AT RECENT TRENDS IN THE GUIDANCE THE COMING
COLD SNAP WILL LIKELY BE JUST A TAD MILDER THAN IT`S COUNTERPART
EARLIER THIS MONTH IF ANY SOLACE CAN BE TAKEN. THAT SAID IT WON`T
BE THAT PLEASANT AS DAYTIME HIGHS RANGE FROM -5F TO +5F TUE/WED
AND MODERATING ONLY VERY SLOWLY THU/FRI BY ABOUT 5 DEG EACH DAY.
LOWS GENERALLY IN THE -5F TO -15F RANGE MON NT/WED NT/THU NT WITH
COLDEST NIGHT LIKELY TUESDAY NIGHT WHEN VALUES SHOULD BOTTOM OUT
FROM 10 TO 20 BELOW. IN TERMS OF SENSIBLE WEATHER A PRETTY BORING
PATTERN HOWEVER. OUTSIDE SOME POSSIBLE WIND CHILL ISSUES MONDAY
NIGHT...NOT MUCH TO TALK ABOUT OTHER THAN THE COLD AS ARCTIC HIGH
PRESSURE MAINTAINS BROAD SYNOPTIC SCALE SUBSIDENCE AND DRY WEATHER
ACROSS THE AREA. BY FRIDAY NIGHT/SATURDAY...SOME HINTS AT A WEAK
NRN STREAM CLIPPER LOW POSSIBLY SPARKING SOME WARM ADVECTION-
DRIVEN LIGHT SNOWS/SHSN ACROSS THE AREA BUT NOTHING MORE THAN
TOKEN 30/40 POPS AT THIS POINT GIVEN WE`RE TALKING 7 DAYS OUT.
&&
.AVIATION /11Z SATURDAY THROUGH WEDNESDAY/...
THROUGH 12Z SUNDAY...MAINLY VFR CONDS EXPECTED THROUGH 18Z UNDER
LIGHT FLOW LESS THAN 10 KTS. SOME BKN/OVC VFR CIGS DURING THIS
PERIOD...BUT GENERALLY AT 060 AGL AND ABOVE. AFTER 18Z BKN/OVC
CIGS GRADUALLY LOWER WITH PERIODS OF MVFR AND/OR IFR LIGHT SNOW
POSSIBLE...ESP AT KMPV/KRUT AND KMSS. WINDS LIGHT...THOUGH
TRENDING NORTH TO NORTHEASTERLY THROUGH TIME. AREAS OF LIGHT SNOW
TAPER OFF TONIGHT LEAVING BKN/OVC VFR/MVFR CONDS WITH PATCHY BR
HERE AND THERE IN THE 3-6SM RANGE. WINDS LIGHT.
OUTLOOK 12Z SUNDAY THROUGH WEDNESDAY...
12Z SUN THROUGH 12Z MONDAY...VFR WITH SCT MVFR/IFR IN SHSN AS
ARCTIC FRONT PUSHES THROUGH THE AREA. BEST SHSN COVERAGE 18-06Z.
12Z MONDAY ONWARD...MAINLY VFR WITH HIGH PRESSURE.
&&
.EQUIPMENT...
AS OF 400 AM EST SATURDAY...THE KTYX 88D DOPPLER RADAR LOCATED IN
NORTHERN NEW YORK REMAINS OUT OF SERVICE DUE TO A FAILED POWER
SUPPLY. PARTS ARE ON ORDER TO REPAIR THE PROBLEM BUT IT WILL
LIKELY BE OUT OF SERVICE THROUGH AT LEAST TUESDAY JANUARY 21.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...LAHIFF
NEAR TERM...LAHIFF
SHORT TERM...LAHIFF
LONG TERM...JMG
AVIATION...JMG
EQUIPMENT...WFO BTV
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
514 AM CST SAT JAN 18 2014
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 312 AM CST SAT JAN 18 2014
MAIN FORECAST CONCERN THROUGH THE SHORT TERM CENTERED ON
ACCUMULATING SNOW TODAY.
WATER VAPOR/SURFACE ANALYSIS SHOW VIGOROUS LOW PRESSURE MOVING OUT
OF EASTERN ND SOUTHEAST INTO MN. RADAR AND SURFACE OBSERVATIONS
SHOWING AN EXPANSIVE NW-SE BAND OF LIGHT TO MODERATE SNOWFALL IN
ADVANCE OF THE LOW AND ATTENDANT WARM FRONTAL BOUNDARY EXTENDING
ACROSS MOST OF MN. INDICATION OF THE STRONG BAROCLINICITY ASSOCIATED
WITH THIS WAVE EVIDENCED BY TEMPERATURES RANGING FROM THE 30S ACROSS
THE DAKOTAS TO READINGS ONLY IN THE SINGLE DIGITS ABOVE AND BELOW
ZERO ACROSS THE NWS LA CROSSE FORECAST AREA.
MODELS ALL HONED INTO PROGGED TRACK OF THE LOW...TAKING IT SOUTHEAST
INTO SOUTH CENTRAL MN BY 12Z AND THEN INTO CENTRAL IL BY SUN 00Z.
DYNAMICS FAIRLY IMPRESSIVE WITH THE SYSTEM WITH STRONG ISENTROPIC
LIFT INDICATED BY RAP ON THE 275K SURFACE AND WEAK TO MODERATE
FRONTOGENETIC FORCING IN THE 1000-700MB LAYER. BUFKIT ALSO SHOWING
AROUND 17 MICROBARS OF LIFT THROUGH THE DENDRITIC GROWTH ZONE AT
KRST EARLY ON THIS MORNING. SNOW TO LIQUID RATIOS SHOULD BE FAIRLY
HIGH AS A RESULT...SOMEWHERE IN THE 16-18 TO 1 RANGE. GIVEN THIS AND
THE TRACK OF THE LOW...HEAVIEST SNOW BAND WILL SET UP ALONG AN AXIS
FROM DODGE CENTER AND ROCHESTER THROUGH DUBUQUE IA WHERE AROUND 4 TO
LOCALLY 5 INCHES IS EXPECTED THROUGH THE DAY. AS A RESULT...A WINTER
WEATHER ADVISORY REMAINS IN EFFECT UNTIL 6 PM THIS EVENING FOR ALL
OF SOUTHEAST MN/NORTHEAST IA..AND COUNTIES IN WI BORDERING THE
MISSISSIPPI AND WISCONSIN RIVERS. LOOKS LIKE MOST OF THE
ACCUMULATING SNOW MAY BE DONE/SHIFTED SOUTHEAST OF THE AREA BEFORE
6PM...BUT SOME DRIFTING OF THE SNOW WITH INCREASING NORTH WINDS ON
THE BACKSIDE OF THE LOW MAY STILL CAUSE SOME DRIVING
DIFFICULTIES...SO WILL LET IT UP THE THE DAYSHIFT TO ASSESS THE
STATUS OF THE ADVISORY HEADLINE GOING INTO THE AFTERNOON.
OTHERWISE...TEMPERATURES TODAY EXPECTED TO MODERATE INTO THE UPPER
TEENS TO MIDDLE 20S.
A RIDGE OF HIGH PRESSURE MOVES ACROSS THE AREA TONIGHT WITH WARM AIR
ADVECTION KICKING IN AFTER MIDNIGHT. LOOK FOR LOWS OCCURRING AROUND
MIDNIGHT IN THE UPPER SINGLE DIGITS/LOWER TEENS...THEN SLOWING
CLIMBING THROUGH THE TEENS AFTER MIDNIGHT.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 312 AM CST SAT JAN 18 2014
MILDER DAY ON TAP FOR SUNDAY AS WARM AIR ADVECTION CONTINUES IN
ADVANCE OF A COLD FRONT MOVING SOUTHWARD OUT OF CANADA INTO NORTHERN
WI. LOOK FOR HIGHS TOPPING OFF IN THE MIDDLE 20S TO THE MIDDLE 30S.
THE COLD FRONT WILL CONTINUE MOVING SLOWLY SOUTHWARD ACROSS THE AREA
SUNDAY NIGHT AS A WEAK MID-LEVEL WAVE RIPPLES ALONG THE BAROCLINIC
ZONE IN PLACE. THIS WILL GIVE THE AREA A CHANCE FOR SOME VERY LIGHT
SNOWFALL.
THE COLD FRONT WILL ALSO MARK THE TRANSITION BACK TO COLDER THAN
NORMAL NORTHWEST FLOW GRIPPING THE REGION AGAIN. MODELS ALSO SHOW
VARIOUS EMBEDDED SHORTWAVE TROUGHS WITHIN THE FLOW FOR ON/OFF LIGHT
SNOW CHANCES THROUGH FRIDAY. CONFIDENCE ON TIMING THESE WAVES PRETTY
LOW AT THIS TIME WITH VARIOUS MODEL SOLUTIONS. OTHERWISE...LOOK FOR
HIGH TEMPERATURES GENERALLY IN THE SINGLE DIGITS AND TEENS ABOVE
ZERO WITH LOWS IN THE SINGLE DIGITS AND TEENS BELOW ZERO. APPEARS
WIND CHILL HEADLINES WILL LIKELY BE NEEDED MONDAY NIGHT/TUESDAY
MORNING AS WIND CHILL VALUES DIP INTO THE 20S TO NEAR 30 BELOW ZERO.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 512 AM CST SAT JAN 18 2014
TAF SITES ARE IN THE THROWS OF AN ACCUMULATING SNOWFALL SYSTEM
THROUGH 15Z OR SO BEFORE CONDITIONS IMPROVE. THE RADAR BAND ON
RADAR IS SHIFTING SLIGHTLY EAST OF KRST AND DO EXPECT A SLIGHT
IMPROVEMENT TO 3/4SM TO 1SM BY TAF START UP. THE BAND IS HEADING
FOR KLSE AND SNOW WILL COME IN SUDDENLY WITH LIFR OCCURRING WITHIN AN
HOUR OF SNOWFALL START. KLSE VSBY SHOULD REMAIN AT 1/2-1SM UNTIL
MID-MORNING. BY 18Z VFR CONDITIONS ARE EXPECTED AT BOTH SITES AS
THE SYSTEM PULLS AWAY TO THE SOUTHEAST.
3-4 INCHES OF SNOW IS EXPECTED FROM THIS FAST MOVING SYSTEM.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR WIZ032-
033-041-053>055-061.
MN...WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR MNZ079-
086>088-094>096.
IA...WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR
IAZ008>011-018-019-029-030.
&&
$$
SHORT TERM...DAS
LONG TERM....DAS
AVIATION...BAUMGARDT
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
519 PM EST SAT JAN 18 2014
.SYNOPSIS...
AN APPROACHING COLD FRONT WILL MOVE THROUGH THE FORECAST AREA LATE
TONIGHT AND EARLY SUNDAY. A PRESSURE RIDGE WILL BE SOUTH OF THE AREA
SUNDAY THROUGH MONDAY. ANOTHER COLD FRONT WILL SWEEP THROUGH THE
AREA TUESDAY. ARCTIC HIGH PRESSURE BEHIND THIS FRONT WILL DOMINATE
WEDNESDAY THROUGH FRIDAY.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
THE APPROACHING COLD FRONT WILL BE NEAR THE FORECAST AREA TOWARD
SUNRISE. LATEST HRRR INDICATES SHOWERS ASSOCIATED WITH THE FRONT
WILL DISSIPATE BEFORE GETTING OVER THE MOUNTAINS. ALL OF THE GFS
AND NAM MOS GIVE POPS LESS THAN 20 PERCENT AND THIS APPEARS
REASONABLE BECAUSE OF THE PRESSURE RIDGE SOUTH OF THE AREA
CONTINUING TO LIMIT MOISTURE AHEAD OF THE FRONT. MIXING AND
CLOUDINESS SHOULD HELP HOLD UP TEMPERATURES TONIGHT. LEANED
TOWARD THE WARMER TEMPERATURE GUIDANCE.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY/...
FURTHER DRYING WILL OCCUR BEHIND THE COLD FRONT SUNDAY MORNING. IT
WILL BE BREEZY. THE NAM BUFKIT MOMENTUM TRANSFER TOOL SUPPORTS GUSTS
NEAR 25 KNOTS. A LAKE WIND ADVISORY MAY BE NEEDED. THE SURFACE RIDGE
SOUTH OF THE AREA WILL CONTINUE TO MAINTAIN A DRY WESTERLY FLOW WITH
LITTLE MOISTURE RECOVERY AHEAD OF THE NEXT COLD FRONT APPROACHING
MONDAY. THE TEMPERATURE GUIDANCE WAS CLOSE. WARMING AHEAD OF THE
COLD FRONT WILL SUPPORT ABOVE NORMAL HIGH TEMPERATURES MONDAY.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
THE GFS AND ECMWF MAINTAIN UPPER-LEVEL TROUGHING OVER THE EASTERN
PART OF THE NATION DURING THE MEDIUM-RANGE PERIOD. THE MODELS
INDICATE LITTLE MOISTURE ASSOCIATED WITH REINFORCING COLD FRONTS
TUESDAY AND THURSDAY. THE GFS...ECMWF...AND EKD MOS SUPPORT NEAR
NORMAL TEMPERATURES TUESDAY DURING THE TIME OF FRONTAL PASSAGE. THE
GUIDANCE INDICATES MUCH BELOW NORMAL TEMPERATURES DURING THE REST
OF THE PERIOD.
&&
.AVIATION /22Z SATURDAY THROUGH THURSDAY/...
HIGH CONFIDENCE IN VFR CONDITIONS THROUGH THE TAF PERIOD.
RIDGE OF HIGH PRESSURE CURRENTLY CENTERED OVER THE REGION WILL
RETREAT SOUTHWARD THIS EVENING AS ANOTHER COLD FRONT APPROACHES
FROM THE WEST THEN CROSSES THE AREA TOWARD DAYBREAK SUNDAY
MORNING. WINDS WILL CONTINUE TO BE THE MAIN ISSUE THROUGH THE
PERIOD. CURRENT WESTERLY WINDS AT 12 TO 14 KNOTS WITH GUSTS UP TO
22 KNOTS WILL PERSIST THROUGH 23Z...THEN SUBSIDE TO AROUND 8
KNOTS AND BACK TO SOUTHERLY BY 19/04Z...FINALLY VEERING BACK TO
WESTERLY AROUND 13 KNOTS WITH GUSTS UP TO 24 KNOTS FROM 19/11
THROUGH THE END OF THE PERIOD. AS THE COLD FRONT PASSES THERE WILL
BE SOME LOW AND MID LEVEL CLOUDS...HOWEVER NO RESTRICTIONS ARE
EXPECTED.
EXTENDED AVIATION OUTLOOK...BREEZY CONDITIONS POSSIBLE AT TIMES
SUNDAY AFTERNOON THROUGH WEDNESDAY.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
425 PM CST SAT JAN 18 2014
.DISCUSSION...
228 PM CST
REST OF TODAY...
SURFACE LOW IS DIVING SOUTHEAST INTO WEST CENTRAL ILLINOIS THIS
AFTERNOON WITH A NARROW BAND OF MODERATE TO HEAVY SNOW STRETCHING
ACROSS NORTH CENTRAL ILLINOIS INTO NORTHWEST INDIANA. SYSTEM HAS
BEEN FAIRLY WELL BEHAVED SO FAR WITH REPORTS OF AROUND 3-4 INCHES IN
THE AREAS THAT HAVE SEEN THE MOST SNOW THUS FAR. DECENT PACKING OF
THE PRESSURE IS NOTED ON THE 280-285K THETA SURFACES...WITH THE BEST
ASCENT PROGGED TO GRADUALLY SHIFT SOUTHEAST OUT OF THE CWA BY MID
EVENING. RAP H7 F-GEN SEEMS TO INITIALIZE NICELY...LINING UP WELL
WITH RADAR AND STRETCHING FROM THE SOUTH SUBURBS INTO NORTHWEST
INDIANA...AND PIVOTING TO THE EAST OUT OF THE AREA. THE RAP DOES
PICK UP ON F-GEN RESTRENGTHENING THIS EVENING OVER A SIMILAR AREA
AND GRADUALLY SINKING SOUTH ACROSS THE REMAINDER OF THE CWA BY LATE
THIS EVENING. WITH THIS IN MIND...DID SLOW DOWN THE TIMING OF SNOW
ENDING THIS EVENING IN THE GRIDS BY A FEW HOURS.
TONIGHT THROUGH SUNDAY...
THE POTENT UPPER WAVE THAT IMPACTED THE AREA TODAY WILL DEPART
ACROSS THE OHIO VALLEY THIS EVENING AND TONIGHT WITH MID/UPPER
RIDGING BUILDING INTO THE UPPER MIDWEST AND WESTERN LAKES REGION.
STRONG SFC PRESSURE RISES WILL MOVE IN BEHIND THE QUICKLY DEPARTING
LOW AND IS EXPECTED TO LEAD TO BREEZY CONDITIONS THIS
EVENING...MAINLY SOUTH OF I-80. FAIRLY STRONG HEIGHT RISES ALOFT
WILL ALSO OVERSPREAD THE AREA...PERSISTING THROUGH THE DAY SUNDAY
AND SHOULD PROVIDE A BRIEF RESPITE IN THE PRECIPITATION. ONCE THE
SURFACE/LOW LEVEL RIDGE AXIS PASSES OVER THE AREA LATE
TONIGHT...WINDS WILL BACK TO THE SOUTHWEST AND WARMER AIR WILL
ADVECT OVERHEAD...WITH H85 TEMPS RISING TO AROUND 2-3C BY SUNDAY
MORNING. SURFACE TEMPERATURES SHOULD REBOUND TO NEAR THE FREEZING
MARK DURING THE DAY SUNDAY...OTHERWISE SHOULD BE A QUIET WEATHER DAY
TOMORROW.
MONDAY THROUGH TUESDAY ...
MAIN CONCERN AS WE HEAD INTO NEXT WEEK WILL BE THE RETURN OF COLD
ARCTIC AIR. WEST COAST RIDGE IS PROGGED TO AMPLIFY OVER THE
WEEKEND...STRETCHING NORTH ACROSS ALASKA WHICH IN COMBINATION WITH A
DEEPENING LOW OVER ONTARIO WILL DISLODGE AIR FROM THE ARCTIC SOUTH
INTO THE NORTHERN LAKES REGION SUNDAY INTO MONDAY. THE LEADING EDGE
OF THIS COLD AIRMASS WILL SINK SOUTH BEHIND A COLD FRONT THAT WILL
PASS SOUTH OVER THE AREA EARLY MONDAY. TEMPERATURES BEHIND THE FRONT
ARE EXPECTED TO BE FALLING THROUGH THE DAY MONDAY. H85 TEMPS ARE
EXPECTED TO FALL TO AROUND -20C AND GENERALLY PERSIST THROUGH THE
END OF THE WEEK. STEEP LOW LEVEL LAPSE RATES DEVELOP BEHIND THE
FRONT AND APPEARS FAVORABLE FOR COLD AIR CU WITH SOME FLURRIES
DEVELOPING IF NOT A FEW SNOW SHOWERS. ACROSS NORTHWEST
INDIANA...WILL ALSO HAVE TO KEEP AN EYE ON THE LAKE EFFECT MACHINE
WHICH WILL BE RAMPING UP...AND APPEARS VERY FAVORABLE TO SEE SOME
SIGNIFICANT SNOW ACCUMULATIONS IN OR NEAR OUR EASTERN COUNTIES.
OVER LAND...LAPSE RATES WEAKEN MONDAY NIGHT AND APPEARS THAT WE
SHOULD BE WELL ENTRENCHED IN THE COLD/DRY AIR TUESDAY LEADING TO
MOST AREAS STAYING DRY OUTSIDE OF THE LAKE EFFECT.
WEDNESDAY THROUGH FRIDAY...
REGION REMAINS UNDER AN ACTIVE NORTHWEST FLOW PATTERN THROUGH THE
END OF NEXT WEEK RESULTING IN SEVERAL PERIODS OF SNOWFALL AS WAVES
ROTATE ACROSS THE AREA. MODELS HAVE BEEN TRENDING TOWARDS A MORE
ROBUST UPPER WAVE DROPPING ACROSS THE REGION MIDWEEK. SHOULD THIS
PAN OUT...MIGHT SEE A BRIEF/MODEST WARMUP AHEAD OF THE SYSTEM...BUT
THEN EVEN COLDER AIR SPILLING BEHIND. BOTH GEM AND ECMWF INDICATE
TEMPS FALLING TO AROUND -24C AT H85 WEDNESDAY. WHILE ITS PROBABLY A
BIT FAR OUT TO START TALKING LOW TRACK AND POTENTIAL SNOW...FOR NOW
AT LEAST MODELS INDICATE THE LOW WILL STAY NORTH OF THE CWA.
TEMPERATURES SHOULD REMAIN WELL BELOW NORMAL WEDNESDAY AND
THURSDAY...AND ARE EXPECTED TO BEGIN TO MODERATE SOME BY FRIDAY.
DEUBELBEISS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 22Z...
* SNOW BECOMING MORE INTERMITTENT BEFORE ENDING EARLY THIS
EVENING...MAY SEE GREATER VARIABILITY IN VSBY WITH TIME AS SNOW
COVERAGE WANES.
* EAST-SOUTHEAST WINDS TURNING NORTHEAST LATE AFTERNOON...THEN
NORTH-NORTHWEST TOWARD 02/03Z.
MDB
//DISCUSSION...UPDATED 22Z...
MAIN AXIS OF HEAVY SNOW HAS BEEN SHIFTING SOUTHEAST IN THE LAST
FEW HOURS BUT INTERMITTENT BANDS OF MORE INTENSE SNOW STILL REMAIN
NEAR THE TERMINALS. WITH THE LOW PASSING TO THE SOUTH...WARM
ADVECTION CONTINUES TO GENERATE SOME NORTHWARD MOVING SNOW BANDS
INTO THE CHICAGO/NW INDIANA AREA BUT COVERAGE IS BECOMING MORE
BROKEN SO A HIGHER VARIABILITY IN CONDITIONS IS LIKELY TO
DEVELOP...WITH 3-5SM VSBY BECOMING POSSIBLE AT ORD/MDW/DPA TOWARDS
23-00Z WITH PERIODIC REDUCTIONS TO 1-2SM STILL POSSIBLE GOING INTO
THE EARLY EVENING AS SNOW BANDS AFFECT THE AREA. CIGS ARE ALSO
BECOMING VARIABLE BUT IMPROVING AND EXPECT THEM TO REMAIN MAINLY
MVFR OR BETTER. WINDS ARE BEGINNING TO TURN EASTERLY IN THE
CHICAGO AREA WITH NORTHEAST WINDS BACK TOWARDS RFD...SO THE SHIFT
TO NORTHEAST IS UNDERWAY AND WILL SPREAD EASTWARD. A SHIFT TO
NORTH-NORTHWEST IS STILL EXPECTED GOING INTO THE MID EVENING.
MDB
FROM 18Z...
SNOW HAS SPREAD OVER THE TAF SITES AND WILL CONTINUE THROUGH THE
AFTERNOON. THE HEAVIEST SNOW WILL REMAIN TO THE SOUTH OF THE TAF
SITES...HOWEVER RADAR AND METEOROLOGICAL ANALYSIS INDICATE THAT
POCKETS OF HEAVIER SNOW EXTEND NORTH FROM THERE WITH 1/2-3/4SM AT
TIMES NEAR OR AT TAF SITES...WITH ACCOMPANYING TEMPORARY SNOWFALL
RATES OF ONE INCH PER HOUR OR SLIGHTLY HIGHER. WINDS WILL CONTINUE
TO BACK TOWARD EASTERLY BY SUNSET AS THE SYSTEM LOW PRESSURE
PASSES TO THE SOUTH. THESE WINDS WILL THEN BACK QUICKLY TO THE
NORTHWEST BY MID EVE OR SO. SPEEDS WILL BE ON THE INCREASE QUICKLY
ON SUNDAY AS THE PRESSURE GRADIENT TIGHTENS. ANY LINGERING LOW
CLOUDS FROM LATE TONIGHT SHOULD DISSIPATE QUICKLY ON SUNDAY
MORNING.
MTF
//ORD AND MDW CONFIDENCE...UPDATED 22Z...
* HIGH CONFIDENCE IN SNOW COVERAGE WANING...THOUGH NOT ENDING FOR
A FEW HOURS...HIGH CONFIDENCE IN MORE VARIABLE VSBY...WITH 3-5SM
BECOMING MORE LIKELY BUT PERIODIC 1-2SM OCCURRING AS SNOW BANDS
PASS.
* HIGH CONFIDENCE IN WIND DIRECTION AND SPEED TRENDS...MEDIUM-HIGH
CONFIDENCE IN TIMING OF SHIFT TO NORTH-NORTHWEST.
MDB
//OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z...
SUNDAY NIGHT...MAINLY VFR. A FEW FLURRIES NORTH OF ORD/MDW.
MONDAY...SLGT CHC OF SNOW SHOWERS.
TUESDAY...MAINLY VFR.
WEDNESDAY-FRIDAY...PERIODIC CHANCES FOR SNOW SHOWERS AND MVFR.
OTHERWISE VFR.
MTF
&&
.MARINE...
307 PM CST
NO CHANGES WERE MADE TO THE ONGOING HEADLINES AS GALES ARE STILL
EXPECTED.
THE LOW IS OVER THE MID MISSISSIPPI RIVER VALLEY AND WHILE IT IS
FILLING SLOWER THAN PREVIOUSLY EXPECTED...IT IS STILL EXPECTED TO
FILL AS MOVES ACROSS SOUTHERN IL. A SECOND LOW IS MOVING INTO
NORTHERN QUEBEC AND ITS COLD FRONT WILL SINK SOUTH DOWN THE LAKE
SUNDAY AND SUNDAY NIGHT. AS THE GRADIENT TIGHTENS
TONIGHT...SOUTHWEST WINDS INCREASE TO GALES OVER THE NORTHERN HALF
TO THE LAKE. WINDS TURN WEST ACROSS THE LAKE AND INCREASE TO LOW END
GALES BY SUNDAY MORNING. WINDS DIMINISH SUNDAY AFTERNOON...AND MAY
COME DOWN BEFORE THE END OF THE GALE WARNING.
WINDS THEN TURN NORTH BEHIND THE FRONT SUNDAY NIGHT AND REMAIN AT 20
TO 25 KT...POSSIBLY UP TO 30 KT AT TIMES...THROUGH MONDAY NIGHT.
HIGH PRESSURE MOVES OVER THE UPPER PLAINS MONDAY NIGHT AND SLIDES
SOUTHEAST REACHING THE SE US WEDNESDAY. WINDS DIMINISH TUESDAY AND
BECOME WEST. GUIDANCE DIFFERS IN REGARDS TO THE PATTERN MID NEXT
WEEK. THE ECMWF FEATURES A DEEP LOW OVER THE LAKE WHILE THE GFS HAS
A WEAK SURFACE TROUGH. BOTH DO FEATURE A HIGH MOVING OVER THE
PLAINS. SO HAVE WINDS BECOMING NORTHWEST AND/OR NORTH WEDNESDAY
NIGHT...AND IF THE LOW IS DEEPER...WINDS COULD BE STRONGER. AS THE
HIGH PASSES TO THE SOUTH LATE NEXT WEEK...WINDS WEAKEN AND BECOME
WEST.
JEE
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...WINTER WEATHER ADVISORY...ILZ008-ILZ010-ILZ011-ILZ019-ILZ020-
ILZ021-ILZ022-ILZ032 UNTIL 6 PM SATURDAY.
WINTER WEATHER ADVISORY...ILZ023-ILZ033-ILZ039 UNTIL 9 PM
SATURDAY.
IN...WINTER WEATHER ADVISORY...INZ010-INZ011-INZ019 UNTIL 9 PM
SATURDAY.
LM...GALE WARNING...LMZ080-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...6 AM SUNDAY TO 3 PM
SUNDAY.
GALE WARNING...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-LMZ567-
LMZ868...MIDNIGHT SUNDAY TO 3 PM SUNDAY.
SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742...3 AM SUNDAY TO 10
PM SUNDAY.
GALE WARNING...LMZ743-LMZ744-LMZ745...9 AM SUNDAY TO 4 PM SUNDAY.
SMALL CRAFT ADVISORY...LMZ743-LMZ744-LMZ745...3 AM SUNDAY TO 9
AM SUNDAY.
&&
$$
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AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
308 PM CST SAT JAN 18 2014
.MESOSCALE DISCUSSION...1225 PM CST
THE IMPRESSIVE AXIS OF HEAVY SNOW CONTINUES TO PIVOT AROUND THE
CLIPPER CIRCULATION CENTER FROM THE DEKALB AREA SOUTHEAST ALL THE
WAY TO DANVILLE AND WEST LAFAYETTE...WITH A PARENT MESOSCALE
CIRCULATION EVIDENT ON THE RADAR MOSAIC IN LASALLE COUNTY. THIS
SNOWFALL BAND HAS HAD RATES OF 2 IN/HR BASED ON NUMEROUS REPORTS
AND RADAR AND VISIBILITY TRENDS INDICATE THIS CONTINUES. THIS
REMAINS DRIVEN BY STRONG MOIST ISENTROPIC ASCENT AND
CONVERGENCE...ROBUST VORTICITY ADVECTION IN THE MID- LEVELS...AND
WELL-DEFINED FRONTONGENSIS BENEATH AN UNSTABLE LAYER. THIS APPEARS
TO BE CONDITIONALLY SYMMETRIC INSTABILITY AND EVEN POSSIBLY
UPRIGHT INSTABILITY THAT IS REALLY SUPPORTING THE HEAVIEST
SNOWFALL. ALL OF THESE ELEMENTS WILL CONTINUE TO FORCE REGULAR
BANDED SNOW...WITH THE HEAVIEST AXIS MOVING INTO THE WESTERN AND
SOUTHERN CHICAGO METRO AREA AND LIKELY PERSISTING THROUGH 3 PM OR
SO...PROVIDING A QUICK COUPLE INCHES AT LEAST. EVEN AS FAR NORTH
AS THE WI STATE LINE...THERE HAVE BEEN TRANSIENT RADAR
ENHANCEMENTS REFLECTING BANDING TO THE NORTH OF THE MAIN HEAVY
AXIS. VISIBILITY HAS DROPPED TO ONE HALF TO THREE QUARTERS OF A
MILE IN THESE AT TIMES.
AFTER 4-5 PM OR SO...THE HEAVIEST RATES SHOULD BE SHIFTING EAST
WITH THE WARM AIR ADVECTION...AND SNOW WILL BE FORCED MORE BY THE
700MB TROUGH MOVING OVERHEAD.
NO SIGNIFICANT CHANGES MADE TO THE WINTER WEATHER ADVISORY OR
FORECAST SNOW FALL AMOUNTS GOING INTO THIS AFTERNOON. THERE WILL
LIKELY BE SOME ISOLATED AREAS AROUND SIX INCHES...NAMELY WESTERN
LEE AND LASALLE COUNTIES WHICH ALREADY HAD A HEAVY BOUT...AND WILL
REMAIN IN A FAVORED CORRIDOR FOR SNOW AS THE CLIPPER PIVOTS TO THE
SOUTHWEST OF THE CWA BEFORE SHIFTING EAST.
WINDS HAVE ALSO PICKED UP A LITTLE MORE IN THE SOUTHEAST CWA AS
THE LOW QUICKLY APPROACHES. THERE PROBABILITY IS SOME BLOWING
SNOW IN RESPONSE WITHIN OPEN AREAS.
&&
.DISCUSSION...
228 PM CST
REST OF TODAY...
SURFACE LOW IS DIVING SOUTHEAST INTO WEST CENTRAL ILLINOIS THIS
AFTERNOON WITH A NARROW BAND OF MODERATE TO HEAVY SNOW STRETCHING
ACROSS NORTH CENTRAL ILLINOIS INTO NORTHWEST INDIANA. SYSTEM HAS
BEEN FAIRLY WELL BEHAVED SO FAR WITH REPORTS OF AROUND 3-4 INCHES IN
THE AREAS THAT HAVE SEEN THE MOST SNOW THUS FAR. DECENT PACKING OF
THE PRESSURE IS NOTED ON THE 280-285K THETA SURFACES...WITH THE BEST
ASCENT PROGGED TO GRADUALLY SHIFT SOUTHEAST OUT OF THE CWA BY MID
EVENING. RAP H7 F-GEN SEEMS TO INITIALIZE NICELY...LINING UP WELL
WITH RADAR AND STRETCHING FROM THE SOUTH SUBURBS INTO NORTHWEST
INDIANA...AND PIVOTING TO THE EAST OUT OF THE AREA. THE RAP DOES
PICK UP ON F-GEN RESTRENGTHENING THIS EVENING OVER A SIMILAR AREA
AND GRADUALLY SINKING SOUTH ACROSS THE REMAINDER OF THE CWA BY LATE
THIS EVENING. WITH THIS IN MIND...DID SLOW DOWN THE TIMING OF SNOW
ENDING THIS EVENING IN THE GRIDS BY A FEW HOURS.
TONIGHT THROUGH SUNDAY...
THE POTENT UPPER WAVE THAT IMPACTED THE AREA TODAY WILL DEPART
ACROSS THE OHIO VALLEY THIS EVENING AND TONIGHT WITH MID/UPPER
RIDGING BUILDING INTO THE UPPER MIDWEST AND WESTERN LAKES REGION.
STRONG SFC PRESSURE RISES WILL MOVE IN BEHIND THE QUICKLY DEPARTING
LOW AND IS EXPECTED TO LEAD TO BREEZY CONDITIONS THIS
EVENING...MAINLY SOUTH OF I-80. FAIRLY STRONG HEIGHT RISES ALOFT
WILL ALSO OVERSPREAD THE AREA...PERSISTING THROUGH THE DAY SUNDAY
AND SHOULD PROVIDE A BRIEF RESPITE IN THE PRECIPITATION. ONCE THE
SURFACE/LOW LEVEL RIDGE AXIS PASSES OVER THE AREA LATE
TONIGHT...WINDS WILL BACK TO THE SOUTHWEST AND WARMER AIR WILL
ADVECT OVERHEAD...WITH H85 TEMPS RISING TO AROUND 2-3C BY SUNDAY
MORNING. SURFACE TEMPERATURES SHOULD REBOUND TO NEAR THE FREEZING
MARK DURING THE DAY SUNDAY...OTHERWISE SHOULD BE A QUIET WEATHER DAY
TOMORROW.
MONDAY THROUGH TUESDAY ...
MAIN CONCERN AS WE HEAD INTO NEXT WEEK WILL BE THE RETURN OF COLD
ARCTIC AIR. WEST COAST RIDGE IS PROGGED TO AMPLIFY OVER THE
WEEKEND...STRETCHING NORTH ACROSS ALASKA WHICH IN COMBINATION WITH A
DEEPENING LOW OVER ONTARIO WILL DISLODGE AIR FROM THE ARCTIC SOUTH
INTO THE NORTHERN LAKES REGION SUNDAY INTO MONDAY. THE LEADING EDGE
OF THIS COLD AIRMASS WILL SINK SOUTH BEHIND A COLD FRONT THAT WILL
PASS SOUTH OVER THE AREA EARLY MONDAY. TEMPERATURES BEHIND THE FRONT
ARE EXPECTED TO BE FALLING THROUGH THE DAY MONDAY. H85 TEMPS ARE
EXPECTED TO FALL TO AROUND -20C AND GENERALLY PERSIST THROUGH THE
END OF THE WEEK. STEEP LOW LEVEL LAPSE RATES DEVELOP BEHIND THE
FRONT AND APPEARS FAVORABLE FOR COLD AIR CU WITH SOME FLURRIES
DEVELOPING IF NOT A FEW SNOW SHOWERS. ACROSS NORTHWEST
INDIANA...WILL ALSO HAVE TO KEEP AN EYE ON THE LAKE EFFECT MACHINE
WHICH WILL BE RAMPING UP...AND APPEARS VERY FAVORABLE TO SEE SOME
SIGNIFICANT SNOW ACCUMULATIONS IN OR NEAR OUR EASTERN COUNTIES.
OVER LAND...LAPSE RATES WEAKEN MONDAY NIGHT AND APPEARS THAT WE
SHOULD BE WELL ENTRENCHED IN THE COLD/DRY AIR TUESDAY LEADING TO
MOST AREAS STAYING DRY OUTSIDE OF THE LAKE EFFECT.
WEDNESDAY THROUGH FRIDAY...
REGION REMAINS UNDER AN ACTIVE NORTHWEST FLOW PATTERN THROUGH THE
END OF NEXT WEEK RESULTING IN SEVERAL PERIODS OF SNOWFALL AS WAVES
ROTATE ACROSS THE AREA. MODELS HAVE BEEN TRENDING TOWARDS A MORE
ROBUST UPPER WAVE DROPPING ACROSS THE REGION MIDWEEK. SHOULD THIS
PAN OUT...MIGHT SEE A BRIEF/MODEST WARMUP AHEAD OF THE SYSTEM...BUT
THEN EVEN COLDER AIR SPILLING BEHIND. BOTH GEM AND ECMWF INDICATE
TEMPS FALLING TO AROUND -24C AT H85 WEDNESDAY. WHILE ITS PROBABLY A
BIT FAR OUT TO START TALKING LOW TRACK AND POTENTIAL SNOW...FOR NOW
AT LEAST MODELS INDICATE THE LOW WILL STAY NORTH OF THE CWA.
TEMPERATURES SHOULD REMAIN WELL BELOW NORMAL WEDNESDAY AND
THURSDAY...AND ARE EXPECTED TO BEGIN TO MODERATE SOME BY FRIDAY.
DEUBELBEISS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* ACCUMULATING SNOW THIS AFTERNOON WITH LIFR VISBY AND MVFR/IFR
CIGS. TEMPORARY 1/4SM VISBY PROBABLE NEAR OR OVER MDW PRIOR TO
22Z.
* SE WINDS BACKING TO EASTERLY BY LATE AFTERNOON WITH SPEEDS
AROUND 10 KT. WINDS THEN BACKING FAIRLY QUICKLY TO NNW DURING
MID EVE.
* GUSTY SW WINDS ON SUNDAY LATE MORNING INTO AFTERNOON.
//DISCUSSION...UPDATED 20Z...
HEAVY BAND OF SNOW FROM KJOT TO KRZL CONTINUES TO MOVE NORTHEAST
AT 20Z...ALTHOUGH IS VERY SLOWLY MOVING NORTHWARD. THERE STILL
ARE POCKETS OF HIGHER DBZ APPROACHING MDW AND GYY AIRPORTS AND PER
COORDINATION BELIEVE IT IS BEST TO MENTION 1/4SM PROBABLE. SUCH
LOW VISIBILITY HAS BEEN SEEN AT TIMES WITH ECHOES OF THIS
MAGNITUDE.
PREV DISCUSSION...UPDATED 18Z...
SNOW HAS SPREAD OVER THE TAF SITES AND WILL CONTINUE THROUGH THE
AFTERNOON. THE HEAVIEST SNOW WILL REMAIN TO THE SOUTH OF THE TAF
SITES...HOWEVER RADAR AND METEOROLOGICAL ANALYSIS INDICATE THAT
POCKETS OF HEAVIER SNOW EXTEND NORTH FROM THERE WITH 1/2-3/4SM AT
TIMES NEAR OR AT TAF SITES...WITH ACCOMPANYING TEMPORARY SNOWFALL
RATES OF ONE INCH PER HOUR OR SLIGHTLY HIGHER. WINDS WILL CONTINUE
TO BACK TOWARD EASTERLY BY SUNSET AS THE SYSTEM LOW PRESSURE
PASSES TO THE SOUTH. THESE WINDS WILL THEN BACK QUICKLY TO THE
NORTHWEST BY MID EVE OR SO. SPEEDS WILL BE ON THE INCREASE QUICKLY
ON SUNDAY AS THE PRESSURE GRADIENT TIGHTENS. ANY LINGERING LOW
CLOUDS FROM LATE TONIGHT SHOULD DISSIPATE QUICKLY ON SUNDAY
MORNING.
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* LOW-MEDIUM IN VISIBILITY...INCLUDING 1/4SM AT MDW.
* MEDIUM-HIGH IN SNOW DURATION AND LOWEST CIGS.
* LOW-MEDIUM IN TOTAL SNOW ACCUMULATION OF 1-2.5 INCHES.
* HIGH IN WINDS THROUGH 01Z...MEDIUM AFTER.
//OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z...
SUNDAY NIGHT...MAINLY VFR. A FEW FLURRIES NORTH OF ORD/MDW.
MONDAY...SLGT CHC OF SNOW SHOWERS.
TUESDAY...MAINLY VFR.
WEDNESDAY-FRIDAY...PERIODIC CHANCES FOR SNOW SHOWERS AND MVFR.
OTHERWISE VFR.
MTF
&&
.MARINE...
307 PM CST
NO CHANGES WERE MADE TO THE ONGOING HEADLINES AS GALES ARE STILL
EXPECTED.
THE LOW IS OVER THE MID MISSISSIPPI RIVER VALLEY AND WHILE IT IS
FILLING SLOWER THAN PREVIOUSLY EXPECTED...IT IS STILL EXPECTED TO
FILL AS MOVES ACROSS SOUTHERN IL. A SECOND LOW IS MOVING INTO
NORTHERN QUEBEC AND ITS COLD FRONT WILL SINK SOUTH DOWN THE LAKE
SUNDAY AND SUNDAY NIGHT. AS THE GRADIENT TIGHTENS
TONIGHT...SOUTHWEST WINDS INCREASE TO GALES OVER THE NORTHERN HALF
TO THE LAKE. WINDS TURN WEST ACROSS THE LAKE AND INCREASE TO LOW END
GALES BY SUNDAY MORNING. WINDS DIMINISH SUNDAY AFTERNOON...AND MAY
COME DOWN BEFORE THE END OF THE GALE WARNING.
WINDS THEN TURN NORTH BEHIND THE FRONT SUNDAY NIGHT AND REMAIN AT 20
TO 25 KT...POSSIBLY UP TO 30 KT AT TIMES...THROUGH MONDAY NIGHT.
HIGH PRESSURE MOVES OVER THE UPPER PLAINS MONDAY NIGHT AND SLIDES
SOUTHEAST REACHING THE SE US WEDNESDAY. WINDS DIMINISH TUESDAY AND
BECOME WEST. GUIDANCE DIFFERS IN REGARDS TO THE PATTERN MID NEXT
WEEK. THE ECMWF FEATURES A DEEP LOW OVER THE LAKE WHILE THE GFS HAS
A WEAK SURFACE TROUGH. BOTH DO FEATURE A HIGH MOVING OVER THE
PLAINS. SO HAVE WINDS BECOMING NORTHWEST AND/OR NORTH WEDNESDAY
NIGHT...AND IF THE LOW IS DEEPER...WINDS COULD BE STRONGER. AS THE
HIGH PASSES TO THE SOUTH LATE NEXT WEEK...WINDS WEAKEN AND BECOME
WEST.
JEE
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...WINTER WEATHER ADVISORY...ILZ008-ILZ010-ILZ011-ILZ019-ILZ020-
ILZ021-ILZ022-ILZ032 UNTIL 6 PM SATURDAY.
WINTER WEATHER ADVISORY...ILZ023-ILZ033-ILZ039 UNTIL 9 PM
SATURDAY.
IN...WINTER WEATHER ADVISORY...INZ010-INZ011-INZ019 UNTIL 9 PM
SATURDAY.
LM...GALE WARNING...LMZ080-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...6 AM SUNDAY TO 3 PM
SUNDAY.
GALE WARNING...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-LMZ567-
LMZ868...MIDNIGHT SUNDAY TO 3 PM SUNDAY.
SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742...3 AM SUNDAY TO 10
PM SUNDAY.
GALE WARNING...LMZ743-LMZ744-LMZ745...9 AM SUNDAY TO 4 PM SUNDAY.
SMALL CRAFT ADVISORY...LMZ743-LMZ744-LMZ745...3 AM SUNDAY TO 9
AM SUNDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
230 PM CST SAT JAN 18 2014
.MESOSCALE DISCUSSION...
1225 PM CST
THE IMPRESSIVE AXIS OF HEAVY SNOW CONTINUES TO PIVOT AROUND THE
CLIPPER CIRCULATION CENTER FROM THE DEKALB AREA SOUTHEAST ALL THE
WAY TO DANVILLE AND WEST LAFAYETTE...WITH A PARENT MESOSCALE
CIRCULATION EVIDENT ON THE RADAR MOSAIC IN LASALLE COUNTY. THIS
SNOWFALL BAND HAS HAD RATES OF 2 IN/HR BASED ON NUMEROUS REPORTS
AND RADAR AND VISIBILITY TRENDS INDICATE THIS CONTINUES. THIS
REMAINS DRIVEN BY STRONG MOIST ISENTROPIC ASCENT AND
CONVERGENCE...ROBUST VORTICITY ADVECTION IN THE MID- LEVELS...AND
WELL-DEFINED FRONTONGENSIS BENEATH AN UNSTABLE LAYER. THIS APPEARS
TO BE CONDITIONALLY SYMMETRIC INSTABILITY AND EVEN POSSIBLY
UPRIGHT INSTABILITY THAT IS REALLY SUPPORTING THE HEAVIEST
SNOWFALL. ALL OF THESE ELEMENTS WILL CONTINUE TO FORCE REGULAR
BANDED SNOW...WITH THE HEAVIEST AXIS MOVING INTO THE WESTERN AND
SOUTHERN CHICAGO METRO AREA AND LIKELY PERSISTING THROUGH 3 PM OR
SO...PROVIDING A QUICK COUPLE INCHES AT LEAST. EVEN AS FAR NORTH
AS THE WI STATE LINE...THERE HAVE BEEN TRANSIENT RADAR
ENHANCEMENTS REFLECTING BANDING TO THE NORTH OF THE MAIN HEAVY
AXIS. VISIBILITY HAS DROPPED TO ONE HALF TO THREE QUARTERS OF A
MILE IN THESE AT TIMES.
AFTER 4-5 PM OR SO...THE HEAVIEST RATES SHOULD BE SHIFTING EAST
WITH THE WARM AIR ADVECTION...AND SNOW WILL BE FORCED MORE BY THE
700MB TROUGH MOVING OVERHEAD.
NO SIGNIFICANT CHANGES MADE TO THE WINTER WEATHER ADVISORY OR
FORECAST SNOW FALL AMOUNTS GOING INTO THIS AFTERNOON. THERE WILL
LIKELY BE SOME ISOLATED AREAS AROUND SIX INCHES...NAMELY WESTERN
LEE AND LASALLE COUNTIES WHICH ALREADY HAD A HEAVY BOUT...AND WILL
REMAIN IN A FAVORED CORRIDOR FOR SNOW AS THE CLIPPER PIVOTS TO THE
SOUTHWEST OF THE CWA BEFORE SHIFTING EAST.
WINDS HAVE ALSO PICKED UP A LITTLE MORE IN THE SOUTHEAST CWA AS
THE LOW QUICKLY APPROACHES. THERE PROBABILITY IS SOME BLOWING
SNOW IN RESPONSE WITHIN OPEN AREAS.
&&
.DISCUSSION...
228 PM CST
REST OF TODAY...
SURFACE LOW IS DIVING SOUTHEAST INTO WEST CENTRAL ILLINOIS THIS
AFTERNOON WITH A NARROW BAND OF MODERATE TO HEAVY SNOW STRETCHING
ACROSS NORTH CENTRAL ILLINOIS INTO NORTHWEST INDIANA. SYSTEM HAS
BEEN FAIRLY WELL BEHAVED SO FAR WITH REPORTS OF AROUND 3-4 INCHES IN
THE AREAS THAT HAVE SEEN THE MOST SNOW THUS FAR. DECENT PACKING OF
THE PRESSURE IS NOTED ON THE 280-285K THETA SURFACES...WITH THE BEST
ASCENT PROGGED TO GRADUALLY SHIFT SOUTHEAST OUT OF THE CWA BY MID
EVENING. RAP H7 F-GEN SEEMS TO INITIALIZE NICELY...LINING UP WELL
WITH RADAR AND STRETCHING FROM THE SOUTH SUBURBS INTO NORTHWEST
INDIANA...AND PIVOTING TO THE EAST OUT OF THE AREA. THE RAP DOES
PICK UP ON F-GEN RESTRENGTHENING THIS EVENING OVER A SIMILAR AREA
AND GRADUALLY SINKING SOUTH ACROSS THE REMAINDER OF THE CWA BY LATE
THIS EVENING. WITH THIS IN MIND...DID SLOW DOWN THE TIMING OF SNOW
ENDING THIS EVENING IN THE GRIDS BY A FEW HOURS.
TONIGHT THROUGH SUNDAY...
THE POTENT UPPER WAVE THAT IMPACTED THE AREA TODAY WILL DEPART
ACROSS THE OHIO VALLEY THIS EVENING AND TONIGHT WITH MID/UPPER
RIDGING BUILDING INTO THE UPPER MIDWEST AND WESTERN LAKES REGION.
STRONG SFC PRESSURE RISES WILL MOVE IN BEHIND THE QUICKLY DEPARTING
LOW AND IS EXPECTED TO LEAD TO BREEZY CONDITIONS THIS
EVENING...MAINLY SOUTH OF I-80. FAIRLY STRONG HEIGHT RISES ALOFT
WILL ALSO OVERSPREAD THE AREA...PERSISTING THROUGH THE DAY SUNDAY
AND SHOULD PROVIDE A BRIEF RESPITE IN THE PRECIPITATION. ONCE THE
SURFACE/LOW LEVEL RIDGE AXIS PASSES OVER THE AREA LATE
TONIGHT...WINDS WILL BACK TO THE SOUTHWEST AND WARMER AIR WILL
ADVECT OVERHEAD...WITH H85 TEMPS RISING TO AROUND 2-3C BY SUNDAY
MORNING. SURFACE TEMPERATURES SHOULD REBOUND TO NEAR THE FREEZING
MARK DURING THE DAY SUNDAY...OTHERWISE SHOULD BE A QUIET WEATHER DAY
TOMORROW.
MONDAY THROUGH TUESDAY ...
MAIN CONCERN AS WE HEAD INTO NEXT WEEK WILL BE THE RETURN OF COLD
ARCTIC AIR. WEST COAST RIDGE IS PROGGED TO AMPLIFY OVER THE
WEEKEND...STRETCHING NORTH ACROSS ALASKA WHICH IN COMBINATION WITH A
DEEPENING LOW OVER ONTARIO WILL DISLODGE AIR FROM THE ARCTIC SOUTH
INTO THE NORTHERN LAKES REGION SUNDAY INTO MONDAY. THE LEADING EDGE
OF THIS COLD AIRMASS WILL SINK SOUTH BEHIND A COLD FRONT THAT WILL
PASS SOUTH OVER THE AREA EARLY MONDAY. TEMPERATURES BEHIND THE FRONT
ARE EXPECTED TO BE FALLING THROUGH THE DAY MONDAY. H85 TEMPS ARE
EXPECTED TO FALL TO AROUND -20C AND GENERALLY PERSIST THROUGH THE
END OF THE WEEK. STEEP LOW LEVEL LAPSE RATES DEVELOP BEHIND THE
FRONT AND APPEARS FAVORABLE FOR COLD AIR CU WITH SOME FLURRIES
DEVELOPING IF NOT A FEW SNOW SHOWERS. ACROSS NORTHWEST
INDIANA...WILL ALSO HAVE TO KEEP AN EYE ON THE LAKE EFFECT MACHINE
WHICH WILL BE RAMPING UP...AND APPEARS VERY FAVORABLE TO SEE SOME
SIGNIFICANT SNOW ACCUMULATIONS IN OR NEAR OUR EASTERN COUNTIES.
OVER LAND...LAPSE RATES WEAKEN MONDAY NIGHT AND APPEARS THAT WE
SHOULD BE WELL ENTRENCHED IN THE COLD/DRY AIR TUESDAY LEADING TO
MOST AREAS STAYING DRY OUTSIDE OF THE LAKE EFFECT.
WEDNESDAY THROUGH FRIDAY...
REGION REMAINS UNDER AN ACTIVE NORTHWEST FLOW PATTERN THROUGH THE
END OF NEXT WEEK RESULTING IN SEVERAL PERIODS OF SNOWFALL AS WAVES
ROTATE ACROSS THE AREA. MODELS HAVE BEEN TRENDING TOWARDS A MORE
ROBUST UPPER WAVE DROPPING ACROSS THE REGION MIDWEEK. SHOULD THIS
PAN OUT...MIGHT SEE A BRIEF/MODEST WARMUP AHEAD OF THE SYSTEM...BUT
THEN EVEN COLDER AIR SPILLING BEHIND. BOTH GEM AND ECMWF INDICATE
TEMPS FALLING TO AROUND -24C AT H85 WEDNESDAY. WHILE ITS PROBABLY A
BIT FAR OUT TO START TALKING LOW TRACK AND POTENTIAL SNOW...FOR NOW
AT LEAST MODELS INDICATE THE LOW WILL STAY NORTH OF THE CWA.
TEMPERATURES SHOULD REMAIN WELL BELOW NORMAL WEDNESDAY AND
THURSDAY...AND ARE EXPECTED TO BEGIN TO MODERATE SOME BY FRIDAY.
DEUBELBEISS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* ACCUMULATING SNOW THIS AFTERNOON WITH LIFR VISBY AND MVFR/IFR
CIGS. TEMPORARY 1/4SM VISBY PROBABLE NEAR OR OVER MDW PRIOR TO
22Z.
* SE WINDS BACKING TO EASTERLY BY LATE AFTERNOON WITH SPEEDS
AROUND 10 KT. WINDS THEN BACKING FAIRLY QUICKLY TO NNW DURING
MID EVE.
* GUSTY SW WINDS ON SUNDAY LATE MORNING INTO AFTERNOON.
//DISCUSSION...UPDATED 20Z...
HEAVY BAND OF SNOW FROM KJOT TO KRZL CONTINUES TO MOVE NORTHEAST
AT 20Z...ALTHOUGH IS VERY SLOWLY MOVING NORTHWARD. THERE STILL
ARE POCKETS OF HIGHER DBZ APPROACHING MDW AND GYY AIRPORTS AND PER
COORDINATION BELIEVE IT IS BEST TO MENTION 1/4SM PROBABLE. SUCH
LOW VISIBILITY HAS BEEN SEEN AT TIMES WITH ECHOES OF THIS
MAGNITUDE.
PREV DISCUSSION...UPDATED 18Z...
SNOW HAS SPREAD OVER THE TAF SITES AND WILL CONTINUE THROUGH THE
AFTERNOON. THE HEAVIEST SNOW WILL REMAIN TO THE SOUTH OF THE TAF
SITES...HOWEVER RADAR AND METEOROLOGICAL ANALYSIS INDICATE THAT
POCKETS OF HEAVIER SNOW EXTEND NORTH FROM THERE WITH 1/2-3/4SM AT
TIMES NEAR OR AT TAF SITES...WITH ACCOMPANYING TEMPORARY SNOWFALL
RATES OF ONE INCH PER HOUR OR SLIGHTLY HIGHER. WINDS WILL CONTINUE
TO BACK TOWARD EASTERLY BY SUNSET AS THE SYSTEM LOW PRESSURE
PASSES TO THE SOUTH. THESE WINDS WILL THEN BACK QUICKLY TO THE
NORTHWEST BY MID EVE OR SO. SPEEDS WILL BE ON THE INCREASE QUICKLY
ON SUNDAY AS THE PRESSURE GRADIENT TIGHTENS. ANY LINGERING LOW
CLOUDS FROM LATE TONIGHT SHOULD DISSIPATE QUICKLY ON SUNDAY
MORNING.
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* LOW-MEDIUM IN VISIBILITY...INCLUDING 1/4SM AT MDW.
* MEDIUM-HIGH IN SNOW DURATION AND LOWEST CIGS.
* LOW-MEDIUM IN TOTAL SNOW ACCUMULATION OF 1-2.5 INCHES.
* HIGH IN WINDS THROUGH 01Z...MEDIUM AFTER.
//OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z...
SUNDAY NIGHT...MAINLY VFR. A FEW FLURRIES NORTH OF ORD/MDW.
MONDAY...SLGT CHC OF SNOW SHOWERS.
TUESDAY...MAINLY VFR.
WEDNESDAY-FRIDAY...PERIODIC CHANCES FOR SNOW SHOWERS AND MVFR.
OTHERWISE VFR.
MTF
&&
.MARINE...
305 AM CST
FAST MOVING CLIPPER SYSTEM...HAS PUSHED SOUTHEAST FROM CENTRAL
CANADA INTO THE NORTHERN PLAINS EARLY THIS MORNING. DOWNSTREAM OF
THIS SYSTEM ACROSS LAKE MICHIGAN HAS BEEN A WEAK SURFACE
RIDGE...WHICH HAS DIMINISHED WINDS TO 10-15KT EARLY THIS MORNING.
THIS WEAK RIDGE OF HIGH PRESSURE WILL QUICKLY SHIFT EAST AHEAD OF
THE LOW PRESSURE...AND ALLOW WINDS TO TURN SOUTHERLY ACROSS THE
CENTRAL/SOUTHERN PORTIONS OF THE LAKE. AS THE LOW ARRIVES FROM THE
NORTHWEST...GUIDANCE CONTINUES TO INDICATE A TIGHTENING GRADIENT.
THIS WILL BE REFLECTED IN WINDS QUICKLY INCREASING TO 20-25KT THIS
EVENING...THEN FURTHER INCREASING TO WEST GALES TO 35 KT FOR THE
NORTHERN HALF OF THE LAKE LATE TONIGHT. THE GRADIENT WILL
EVENTUALLY WORK SOUTH ACROSS THE SOUTHERN PORTIONS OF THE LAKE AND
INCLUDE THE NORTHWEST INDIANA NEARSHORE WATERS WITH GALES TO 35 KT
DEVELOPING EARLY SUNDAY MORNING. GALE CONDITIONS WILL LIKELY
PERSIST THROUGH SUNDAY AFTERNOON...THEN DIMINISH WITH THE PASSAGE
OF A FRONTAL BOUNDARY AND SHIFT TO THE NORTHWEST LATE SUNDAY
NIGHT. WAVES WILL LIKELY REMAIN HAZARDOUS FOR THE INDIANA
NEARSHORE WATERS THROUGH SUNDAY NIGHT...POSSIBLY INTO MONDAY
MORNING.
THEN ANOTHER AREA OF LOW PRESSURE SLIDES SOUTHEAST ACROSS THE LAKE
MONDAY INTO TUESDAY. A BROAD RIDGE OF HIGH PRESSURE SLIDES SOUTH
INTO THE NORTHERN PLAINS TUESDAY...WHICH INTRODUCES ANOTHER TIGHT
PRESSURE GRADIENT AND POSSIBLY PUSH WINDS TO 30KT TUESDAY AFTERNOON
THROUGH TUESDAY NIGHT. THIS WILL ALLOW WAVES TO BUILD FOR THE
SOUTHERN HALF OF LAKE MICHIGAN TUE.
BEACHLER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...WINTER WEATHER ADVISORY...ILZ008-ILZ010-ILZ011-ILZ019-ILZ020-
ILZ021-ILZ022-ILZ032 UNTIL 6 PM SATURDAY.
WINTER WEATHER ADVISORY...ILZ023-ILZ033-ILZ039 UNTIL 9 PM
SATURDAY.
IN...WINTER WEATHER ADVISORY...INZ010-INZ011-INZ019 UNTIL 9 PM
SATURDAY.
LM...GALE WARNING...LMZ080-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...6 AM SUNDAY TO 3 PM
SUNDAY.
GALE WARNING...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-LMZ567-
LMZ868...MIDNIGHT SUNDAY TO 3 PM SUNDAY.
SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742...3 AM SUNDAY TO 10
PM SUNDAY.
GALE WARNING...LMZ743-LMZ744-LMZ745...9 AM SUNDAY TO 4 PM SUNDAY.
SMALL CRAFT ADVISORY...LMZ743-LMZ744-LMZ745...3 AM SUNDAY TO 9
AM SUNDAY.
&&
$$
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 NORTHERN INDIANA
325 PM EST SAT JAN 18 2014
.SYNOPSIS...
ISSUED AT 1121 AM EST SAT JAN 18 2014
ANOTHER STORM SYSTEM WILL DROP INTO THE OHIO VALLEY TONIGHT
BRINGING ANOTHER ROUND OF SNOW TO THE REGION THIS AFTERNOON AND
EVENING. HIGH TEMPERATURES THIS AFTERNOON WILL RANGE FROM THE
UPPER TEENS TO LOWER 20S. LOWS TONIGHT WILL FALL INTO THE TEENS.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 320 PM EST SAT JAN 18 2014
TWO CHALLENGES IN THE SHORT TERM: DURATION/INTENSITY/AMOUNT OF SNOW
AND MIN TEMPERATURE TONIGHT/SUNDAY MORNING.
THE CLIPPER SYSTEM IS WELL FORECAST BY THE MODELS THIS AFTERNOON AND
MORNING INITIALIZATIONS WERE NEARLY SPOT ON. LATEST SATELLITE/RADAR
DATA SHOW THE DEEPENING WAVE AND ASSOCIATED WARM SECTOR ASSENT ON
THE EAST AND NORTHEAST AREA IS HOLDING TOGETHER WELL. EXPECT TO SEE
THE LEADING EDGE OF THE SNOW ACROSS THE SOUTHWEST PORTION OF THE CWA
BETWEEN 2-4 PM EST AND THIS WILL SHIFT NORTH AND EAST DURING THE
EVENING. AM CONCERNED THAT THE DRIER AIR IS STARTING TO WRAP AROUND
THE LOW AND THIS SHOULD BE ENOUGH TO CREATE A VERY NARROW
PRECIPITATION BAND. AS MODELS ARE STARTING TO SHOW...THIS WILL BE A
RAPIDLY MOVING SYSTEM AND WHILE THERE ARE HINTS OF FAVORABLE
FRONTOGENETIC FORCING...THE RAPID TRANSITORY NATURE WILL RESULT
GENERAL AREAS OF SNOWFALL WITH EMBEDDED BANDS OF ENHANCED SNOWFALL.
BY MIDNIGHT...THE SYSTEM WILL HAVE BECOME MORE OF AN OPEN WAVE AND
THIS WILL BRING THE SNOWFALL TO A QUICK END FROM WEST TO EAST. MODEL
SOUNDINGS SUGGEST THAT CLOUDS/STRATUS WILL PERSIST OVER MUCH OF THE
AREA...BUT THIS LEADS TO THE SECOND CHALLENGE FOR THE PERIOD. AS THE
TROF OPENS UP AND THE FLOW TURNS MORE WESTERLY...THE POTENTIAL FOR
CLEARING SKIES IS BECOMING MORE LIKELY. AS A RESULT HAVE TRIMMED THE
OVERNIGHT LOWS A FEW DEGREES. THE RUC AND LOCAL WRF ARE BY FAR THE
COOLEST OF THE MODELS AT THIS TIME AND GIVEN THE CLEARING NOTED IN
THE WAKE OF THE SYSTEM...FEEL COMPELLED TO LEAN TOWARD THE COOLER
SOLUTIONS. ONLY A MINOR DOWNWARD ADJUSTMENT MADE.
EXPECT TO SEE A FEW LAKE ENHANCED SNOW SHOWERS DURING THE DAY SUNDAY
WITH FAVORED AREAS NEAR THE SHORELINE AND LIGHT SNOW SHOWERS ALONG
AND NORTH OF US-30.
&&
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 320 PM EST SAT JAN 18 2014
ONCE AGAIN VERY FEW CHANGES NEEDED TO LONG TERM WITH PERSISTENT BUT
ACTIVE PATTERN. LONG WAVE TROUGH REMAINS ANCHORED OVER THE GREAT
LAKES WITH LARGE SCALE RIDGE OVER WEST COAST. DEEP NORTHERLY FLOW
WILL KEEP THE POLAR EXPRESS OF SHORT WAVES ON TRACK WITH SEVERAL
WAVES OVER THE NEXT WEEK. LAKE EFFECT WILL BE ONGOING FOR ABOUT THE
ENTIRE PERIOD BUT BACKING AND VEERING WINDS MAKE BAND ORIENTATION
AND PLACEMENT DIFFICULT AT BEST AT THIS TIME RANGE.
NEXT ARCTIC BOUNDARY STILL SET TO PLUNGE SOUTH ACROSS THE AREA ON
MONDAY. EARLY MORNING HIGHS EXPECTED WITH WINDS BECOMING NORTH
THROUGH THE DAY AND COLD AIR ADVECTION DEEPENING. WILL CONTINUE WITH
LOW CHANCE POPS FOR FLURRIES/LIGHT SNOW SHOWERS AS COLD AIR DEEPENS.
LAKE EFFECT TO LIKELY BE SLOW AND LIGHT AT FIRST BUT AS SECONDARY
FRONT AND COLDER AIR MOVE IN LATER MONDAY AND ESPECIALLY MONDAY
NIGHT INTO TUESDAY...SHOULD SEE THE LAKE EFFECT MACHINE CRANK INTO
FULL GEAR. STILL EXPECT A SIGNIFICANT SINGLE BAND SOMEWHERE BETWEEN
EXTREME SOUTHWEST BERRIEN COUNTY AND PORTER COUNTY IN NW INDIANA.
THIS WILL DEPEND ON STRENGTH OF CONVERGENCE. UPSTREAM CONDITIONING
EXPECTED WITH LONG FETCH AND EXTREME DELTA TS SO SIGNIFICANT
ACCUMULATIONS LIKELY...JUST A QUESTION OF EXACTLY WHERE. STILL NEED
A FEW MORE MODEL ITERATIONS BEFORE HIGHER RESOLUTION GUIDANCE BEGINS
TO PICK UP THESE PERIODS.
REST OF THE WEEK TO SEE A CONTINUATION OF MEANDERING LAKE EFFECT
BANDS AND COLD TEMPS. AS WE HAVE BEEN DISCUSSING...HIGHS IN SINGLE
DIGITS TO TEENS WITH LOWS AROUND ZERO TO 6 BELOW RIGHT NOW. REALLY
EXPECT SOME COLDER READINGS...ESPECIALLY IF WE DECOUPLE AND ARE
CLEAR TUE NIGHT WITH HIGH PRESSURE MOVING THROUGH AND FRESH SNOWPACK.
COULD SEE LOWS BOTTOM OUT IN RURAL AREAS IN THE 10 TO 15 BELOW RANGE
AGAIN IF IDEAL RADIATIONAL CONDITIONS DEVELOP. FOR NOW STAYED ON THE
CONSERVATIVE SIDE OF COLDER BLENDS AROUND 5 BELOW.
YET ANOTHER SHORT WAVE AND REINFORCED SHOT OF COLD AIR AROUND MID
WEEK WILL KEEP CHANCES FOR SNOW SHOWERS GOING. MEDIUM RANGE MODELS
HINT AT ANOTHER POSSIBLE SINGLE BAND BEHIND THIS WAVE. LOWS THU
NIGHT HAVE POTENTIAL TO GO EVEN LOWER THAN CURRENT FCST LOWS IF HIGH
PRESSURE SLIDES IN AND WE DECOUPLE AGAIN.
SLIGHT MODERATION IN MODELS BEING SHOWN FOR DAY 7 BEFORE NEXT POLAR
EXPRESS SHORT WAVE MOVES IN EARLY IN WEEK TWO PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 320 PM EST SAT JAN 18 2014
(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1210 PM EST SAT JAN 18 2014
WARM ADVECTION AHEAD OF THE SURFACE LOW ON THE IA/IL BORDER
CONTINUES BRINGING IN ENOUGH MOISTURE AND ISENTROPIC ASSENT TO
PRODUCE STRATUS OVER THE FORECAST AREA. PERIODS OF SCT/BKN STRATUS
WILL PERSIST THROUGH THE FIRST FEW HOURS OF THE FORECAST PERIOD
BEFORE BECOMING MORE UNIFORM IN COVERAGE.
WITH THE LOW TRACKING FROM DVN-EVV-LOZ DURING THE TAF PERIOD
LOWEST CIGS/VSBY WILL BE SOUTH AND WEST OF THE TAF LOCATIONS
OVERNIGHT. STILL EXPECT IFR/POSSIBLE LIFR CONDITIONS AFTER 00Z
AND THIS WILL LAST THROUGH MUCH OF THE REMAINDER OF OVERNIGHT...
WITH IMPROVING CONDITIONS DURING THE LATTER PART OF THE FORECAST
PERIOD.
SOME INDICATIONS THAT AS THE LOW OPENS AND LIFTS NORTHEAST DURING
THE DAY SUNDAY THAT THERE WILL BE A PERIOD OF INCREASED BOUNDARY
LAYER WINDS AND THIS COULD LEAD TO LLWS SITUATION VERY LATE IN THE
FORECAST PERIOD. WILL NOT INCLUDE IN THE TAF AT THIS TIME...BUT
WILL MERIT WATCHING.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...WINTER WEATHER ADVISORY UNTIL 1 AM EST SUNDAY FOR INZ025>027-033-
034.
WINTER WEATHER ADVISORY UNTIL 9 PM EST /8 PM CST/ THIS EVENING
FOR INZ012-013-020-022.
WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR INZ015-
023-024-032.
MI...NONE.
OH...NONE.
LM...SMALL CRAFT ADVISORY FROM 7 AM SUNDAY TO MIDNIGHT EST SUNDAY
NIGHT FOR LMZ043-046.
&&
$$
SYNOPSIS...KG
SHORT TERM...LASHLEY
LONG TERM...LEWIS
AVIATION...LEWIS
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.NORTHERNIN.GOV
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1019 AM MST SAT JAN 18 2014
.SHORT TERM...(TODAY THROUGH MONDAY NIGHT)
ISSUED AT 230 AM MST SAT JAN 18 2014
TODAY-TONIGHT...STRONG VORT MAX CURRENTLY MOVING TOWARD NORTHERN
IOWA AND NOSE OF 120KT UPPER JET WILL BOTH SLIDE SOUTH/SOUTHEAST
TODAY THEN ACROSS THE EAST COAST TONIGHT. STRONGEST WINDS ALOFT MOVE
INTO THE AREA THIS MORNING AND CONTINUE THROUGH LATE MORNING/EARLY
AFTERNOON BEFORE SLOWLY DECREASING LATE THIS AFTERNOON THROUGH
SUNSET. LOCAL WIND GUST PROGRAM SUGGESTING GUSTS OF 45 TO 57 KTS
ACROSS THE AREA AT 18Z (STRONGEST AT KGLD AND KITR) WITH 40 TO 46
KTS BY 21Z. SO THE QUESTION BECOMES WILL A HIGH WIND WARNING BE
NEEDED.
MET/MAV GUIDANCE ALL SHOWING SUSTAINED WINDS AROUND 30KTS VERY LATE
THIS MORNING WITH A DECREASING TREND THIS AFTERNOON. 06Z RUC SHOWING
GUSTS 50-52KTS FROM COLBY EAST AROUND 18Z WHICH IS OPPOSITE OF WIND
GUST PROGRAM RESULTS. SEEMS TO BE A LACK OF REALLY FAVORABLE OR EVEN
FAVORABLE LOW AND MID LEVEL LAPSE RATES WHICH IS KEEPING ME FROM
UPGRADING TO A HIGH WIND WARNING. EITHER WAY...IT WILL BE WINDY WITH
GUSTS OVER 50 MPH POSSIBLE ALONG WITH SOME BLOWING DUST FROM TIME
TO TIME.
HIGH TEMPERATURES UPPER 40S NORTHEAST WITH LOW 50S ELSEWHERE. LOWS
TONIGHT IN THE 20S.
SUNDAY-SUNDAY NIGHT...WEATHER STORY FOR THIS PERIOD WILL BE MUCH
ABOVE NORMAL HIGH TEMPERATURES WITH 850 TEMPERATURES AND NEARLY ALL
REMAINING GUIDANCE SUPPORTING UPPER 50S TO MID 60S ACROSS THE AREA.
A FEW LOCATIONS SUCH AS MCCOOK AND HILL CITY WILL BE CLOSE IF NOT
REACH RECORD HIGHS FOR THE DAY. SEE CLIMATE SECTION BELOW. LOWS
IN THE LOW TO MID 20S.
MONDAY-MONDAY NIGHT...COLDER TEMPERATURES RETURN AS 850 TEMPERATURES
DROP ABOUT 15-20F FROM SUNDAYS READINGS PUTTING THE AREA BACK INTO
THE 40S FOR HIGHS...CLOSER TO NORMAL FOR MID JANUARY. LOWS MONDAY
UPPER TEENS TO LOW 20S. LOOKS LIKE ANOTHER BREEZY TO WINDY DAY AND
HAVE INCREASED WINDS A BIT AS A RESULT.
NO PRECIPITATION IS EXPECTED THROUGH THE PERIOD.
.LONG TERM...(TUESDAY THROUGH FRIDAY)
ISSUED AT 230 AM MST SAT JAN 18 2014
A STUBBORN TROUGH/RIDGE PATTERN ACROSS THE CONUS CONTINUES THROUGH
NEXT WEEK. THE RIDGE OVER THE WEST COAST LOOKS TO AMPLIFY TOWARDS
THE END OF THE WEEK WITH H5 HEIGHTS OVER 2 STANDARD DEVIATIONS ABOVE
NORMAL ACROSS THE WESTERN COAST OF CANADA. LOCALLY NORTHWEST FLOW
WILL PERSIST AT UPPER LEVELS WITH A FEW FRONTS OVER THE COURSE OF
THE WEEK. EXTENDED PERIOD WILL BE GENERALLY DRY WITH NEAR SEASONABLE
TEMPS.
TUE AND WED WILL BE MOSTLY SUNNY AND SEASONABLE WITH LIGHT
NORTHWEST WINDS. LATE WEDNESDAY CLOUDS WILL INCREASE AHEAD OF A
BACK DOOR COLD FRONT ASSOCIATED WITH A BROAD AREA OF HIGH PRESSURE
DEVELOPING ACROSS THE NORTHERN PLAINS. COLD CANADIAN AIR WILL
ACCOMPANY THIS SYSTEM...THOUGH LUCKILY THE COLDEST AIR WILL REMAIN
MUCH FARTHER NORTH AND EAST. WHILE THERE IS SOME DISCREPANCIES AS
FAR AS THE COLD GOES...GUIDANCE IS IN FAIRLY GOOD AGREEMENT THAT
WE WILL SEE SOME MID-LEVEL MOISTURE MOVE SOUTH THROUGH THE HIGH
PLAINS AND REACH THE CWA WED NIGHT INTO EARLY THURSDAY. WHILE
LIFT/DYNAMICS ARE NOT VERY GOOD...WOULD NOT BE SURPRISED FOR SEE A
FEW FLURRIES DURING THIS TIME AS WELL...ESPECIALLY IF WE CAN GET
SOME ENHANCEMENT FROM THE RIGHT ENTRANCE REGION OF THE 250MB JET.
THURS WILL BE BREEZY AS THE HIGH PRESSURE OVER THE NORTHERN PLAINS
MOVES EAST. CLOUDS WILL DECREASE LATE IN THE DAY AS WINDS PICK UP
OUT OF THE SOUTH AT 15 TO 20 KTS DUE TO THE STRONG PRESSURE GRADIENT
ACROSS WESTERN KANSAS. FRIDAY WILL BE SEASONABLE...WITH SOME HIGH
CLOUDS LIMITING AFTERNOON TEMPS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1016 AM MST SAT JAN 18 2014
VFR CONDITIONS WILL CONTINUE AT KGLD AND KMCK. STRONG NORTHWEST
WIND WILL SLOWLY DECREASE BY LATE AFTERNOON AS LOW PRESSURE MOVES
EAST AND THE GRADIENT RELAXES. DO NOT EXPECT ANY VISBILITY REDUCTIONS
DUE TO BLOWING DUST THAT WOULD GO DOWN TO MVFR.
&&
.FIRE WEATHER...
ISSUED AT 230 AM MST SAT JAN 18 2014
TODAY...CURRENT RED FLAG WARNING AREAL COVERAGE LOOKS GOOD AS RH
VALUES AROUND 20 PERCENT COMBINE WITH NORTHWEST WINDS GUSTING UP
TO 50 MPH...POSSIBLY A BIT HIGHER IN SPOTS. AS FAR AS
TIMING...CURRENT START TIME MAY BE A FEW HOURS EARLY.
SUNDAY...RH VALUES FALL INTO THE 20-25 PERCENT RANGE ACROSS THE
AREA DURING THE EARLY AFTERNOON. NORTHWEST WINDS OF 15 TO 20 MPH
ARE POSSIBLE CREATING NEAR CRITICAL FIRE WEATHER CONDITIONS.
SOMETHING TO WATCH.
MONDAY...RH VALUES FALL TOWARD 25 PERCENT BY MID AFTERNOON.
NORTHWEST WINDS OF 20 TO 25 MPH WITH HIGHER GUSTS EXPECTED WHICH
WILL CREATE NEAR CRITICAL FIRE WEATHER CONDITIONS. LATER SHIFTS
WILL NEED TO RE-EVALUATE FOR POSSIBLE FIRE WEATHER HIGHLITE.
&&
.CLIMATE...
ISSUED AT 230 AM MST SAT JAN 18 2014
RECORD AND/OR NEAR RECORD HIGH TEMPERATURES ARE POSSIBLE SUNDAY
JANUARY 19 AT HILL CITY AND MCCOOK. CURRENT RECORDS FOR THE DATE
ARE:
HILL CITY...66 IN 2006 AND PREVIOUS YEARS
MCCOOK......66 IN 1997
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...RED FLAG WARNING UNTIL 5 PM MST /6 PM CST/ THIS AFTERNOON FOR
KSZ001-002-013>015-027>029-041-042.
WIND ADVISORY UNTIL 5 PM MST /6 PM CST/ THIS AFTERNOON FOR
KSZ001>004-013>016-027>029-042.
CO...RED FLAG WARNING UNTIL 5 PM MST THIS AFTERNOON FOR COZ252>254.
WIND ADVISORY UNTIL 5 PM MST THIS AFTERNOON FOR COZ090-091.
NE...RED FLAG WARNING UNTIL 5 PM MST THIS AFTERNOON FOR NEZ079.
WIND ADVISORY UNTIL 5 PM MST /6 PM CST/ THIS AFTERNOON FOR
NEZ079>081.
&&
$$
SHORT TERM...99
LONG TERM...JJM
AVIATION...FS
FIRE WEATHER...99
CLIMATE...99
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
447 PM EST SAT JAN 18 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 446 PM EST SAT JAN 18 2014
12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW VERY FAMILIAR UPR
AIR PATTERN WITH DEEP TROF OVER CENTRAL/ERN NAMERICA DOWNSTREAM OF
HI AMPLITUDE RDG OVER THE W. ALTHOUGH SOME LO CLDS/LGT SHSN OR
FLURRIES WERE ARND INTO EARLY AFTN WITH LLVL MSTR TRAPPED UNDER LO
INVRN SHOWN ON THE 12Z INL/GRB RAOBS...ARRIVAL OF DRIER LLVL AIR
DEPICTED ON THE INL RAOB HAS TENDED TO DIMINISH THIS LO CLD.
OTRW...THERE IS RELATIVELY QUIET WX OVER UPR MI TDAY GIVEN SHRTWV
RDG/MID LVL DRY AIR SHOWN ON THE RAOBS DOMINATING THE UPR LKS TO THE
N OF POTENT CLIPPER SHRTWV DIGGING SEWD THRU THE MIDWEST. NEXT
DISTURBANCE IN THE NEVER ENDING PARADE OF CLIPPER SHRTWVS IS NOW
DIGGING SSEWD THRU NRN MANITOBA AND INTO FAR NW ONTARIO. FAIRLY
SHARP PRES FALLS AND EXTENSIVE CLD COVER ARE EVIDENT IN MANITOBA AND
NW ONTARIO AHEAD OF THIS SHRTWV.
MAIN FCST CONCERNS IN THE SHORT TERM INVOLVE IMPACT ON POPS/WINDS/
BLSN OF SHRTWV DIGGING SEWD INTO NW ONTARIO AND TEMPS TRENDS TNGT.
TNGT...SHRTWV/ACCOMPANYING SFC LO OVER NW ONTARIO THIS EVNG ARE
PROGGED TO MOVE TO NEAR JAMES BAY BY 12Z SUN...WITH ATTENDANT COLD
FNT REACHING THE KEWEENAW TOWARD 12Z. MODELS INDICATE THE SFC LO WL
DEEPEN FM ABOUT 995MB THIS EVNG TO 985MB ON SUN MRNG AS THE SHRTWV
DIGS INTO THE MEAN UPR TROF. ALTHOUGH BULK OF THE ACCOMPANYING
DPVA/DEEP LYR QVECTOR CNVGC ARE PROGGED TO SWING THRU ONTARIO AND N
OF THE CWA IN THE 06Z-12Z TIME FRAME...SOME OF THIS FORCING DOES
IMPACT UPR MI. MODELS INDICATE FAIRLY DEEP MOISTENING...WHICH IS
BACKED UP BY COLDER CLD TOPS AND UPSTREAM OBS IN NRN MANITOBA AND
SASKATCHEWAN SHOWING FAIRLY WDSPRD LGT SN EVEN ON THE ACYC SIDE OF
SHRTWV TRACK. GIVEN THESE OBS...SUSPECT THE HIER QPF UP TO 0.20 INCH
OVER THE W THRU 12Z SUN SHOWN BY THE 12Z NAM/REGIONAL GEM MAY BE ON
THE RIGHT TRACK DESPITE MARGINAL H85 TEMPS FOR LES. STRENGTHENING
UPSLOPE W-SW FLOW WOULD ALSO TEND TO ENHANCE PCPN TOTALS IN THIS
AREA. THE COMBINATION OF THE FALLING SN AND GUSTY WINDS OVER THE
MORE EXPOSED KEWEENAW PENINSULA ACCENTUATED BY H925 WINDS UP TO
35-40 KTS WL LIKELY CAUSE BLSN/SHARPLY REDUCED VSBY. PLAN TO REISSUE
SPS FOR THIS AREA. DOWNSLOPE NATURE OF WSW FLOW WL TEND TO LIMIT QPF
OVER THE CNTRL ZNS. AS FOR TEMPS...READINGS MAY FALL OFF FAIRLY
QUICKLY EARLY UNDER CLR-PCLDY SKIES...BUT COMBINATION OF INCRSG
CLDS/WINDS BY LATE EVNG SHOULD CAUSE TEMPS TO REBOUND...ESPECIALLY
IN THE DOWNSLOPE AREAS NEAR LK SUP.
SUN...AS SHRTWV/SFC LO MOVE INTO QUEBEC...ATTENDANT COLD FNT WL
CROSS UPR MI...CLRG MENOMINEE ARND 18Z. THERE MAY BE A PERIOD OF
HEAVIER SHSN/BLSN NEAR LK SUP E OF MQT ACCOMPANYING THE FROPA WITH
WSHFT TO THE NW AND GUSTY WINDS/H925 WINDS STILL NEAR 30 KTS. OPTED
TO INCLUDE THIS AREA IN SPS ISSUED FOR THE NW CWA TNGT. ALTHOUGH
FCST NNW FLOW IN THE WAKE OF THIS FROPA AND H85 TEMPS FALLING TO
ARND -20C OVER THE NRN TIER BY 00Z MON WL BE FVRBL FOR LES IN THE
FAVORED SN BELTS...DEEP LYR QVECTOR DVGC/SUBSIDENCE IN THE WAKE OF
SHRTWV PASSAGE THAT IS FCST TO SHARPEN INVRN ARND 3K FT WL TEND TO
LIMIT THE INTENSITY OF THE LES...ESPECIALLY OVER THE W DOWNWIND OF
MORE ICE BUILDUP OVER WRN LK SUP. EXPECT LESS BLSN IN THE AFTN GIVEN
TREND FOR DIMINISHING WINDS WITH CLOSER APRCH OF ARCTIC HI PRES.
ALTHOUGH ANOTHER CLIPPER SHRTWV IS FCST TO MOVE INTO NRN MN LATER IN
THE DAY WITH SOME DPVA/DEEP LYR QVECTOR CNVGC IMPACTING UPR
MI...FCST SDNGS HINT THERE WL BE TOO MUCH DRYING IN THE WAKE OF
STRONGER QUEBEC CLIPPER TO ALLOW FOR MUCH MORE THAN BKN CLDS AWAY FM
THE LES AREAS.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 446 PM EST SAT JAN 18 2014
A SERIES OF CLIPPERS AND ARCTIC AIR WILL DOMINATE THE LONG TERM
PATTERN AS DEEP TROUGHING ACROSS EASTERN CANADA GENERALLY REMAINS IN
PLACE.
SUNDAY NIGHT THROUGH TUESDAY...A MID-LEVEL LOW IN THE VICINITY OF
JAMES BAY WILL SLOWLY DRIFT EASTWARD ACROSS NORTHERN QUEBEC THROUGH
THE BEGINNING OF THE PERIOD...SENDING A SERIES OF TROUGHS
SOUTHEASTWARD ACROSS UPPER MI. THE FIRST OF THESE WILL CROSS THE
AREA LATE SUNDAY NIGHT IN ASSOCIATION WITH THE CONTINUED ADVECTION
OF ARCTIC AIR ACROSS THE REGION. AN UPTICK IN LES FOR THE N TO NNW
SNOW BELTS IS EXPECTED WITH THE TROUGH PASSAGE AS LAKE EQUILIBRIUM
VALUES SURPASS 9KFT OVER EASTERN LAKE SUPERIOR. HI-RES MODEL
GUIDANCE AND EVEN SOME MEDIUM-RES GUIDANCE IS ALSO STARTING TO
INDICATE A LAKE-INDUCED SFC TROUGH/EASTERLY LAND BREEZE CONV ZONE
NORTH OF GRAND MARAIS. THE LAKE-ICE COVER IS BECOMING MORE
WIDESPREAD OVER FAR EASTERN LAKE SUPERIOR...AND WHITEFISH BAY IS
COMPLETELY FROZEN OVER PER TODAYS SATELLITE IMAGERY. THIS HAS
ALLOWED THE LAND BREEZE CONV ZONE TO SET UP FARTHER WEST TODAY...AND
WOULD EXPECT SIMILAR BEHAVIOR FOR SUNDAY NIGHT...ESPECIALLY WITH
QUITE COLD AIR FLOWING OFF ONTARIO. LITTLE SHOULD CHANGE THROUGH
MONDAY NIGHT AS PERSISTENT NNW FLOW CONTINUES TO BRING ARCTIC AIR
ACROSS THE AREA. SNOWFALL AMOUNTS ARE A LITTLE TRICKY AS THE ARCTIC
AIR TENDS TO MAKE SLR VALUES LOWER. HOWEVER...FROM EXPERIENCE SO FAR
THIS SEASON...THE EXTENDED FETCH FOR THE EASTERN CWA MAY ALLOW FOR
MORE MODERATION OF THE ARCTIC AIR...RESULTING IN A DEEPER FAVORABLE
SNOW GROWTH LAYER. HAVE THUS INCREASED RATIOS A BIT ACROSS THE EAST
WHILE LOWERED THEM ELSEWHERE. ALSO...POROUS ICE COVER DEVELOPING
ACROSS WESTERN LAKE SUPERIOR MAY LIMIT LES TO SOME
DEGREE...ESPECIALLY LOCATIONS DOWNWIND OF ISLE ROYALE. OVERALL...NOT
ANTICIPATING ANY EXTREME SNOWFALL UNLESS A CONVERGENT BAND REMAINS
ANCHORED OVER A GIVEN LOCATION...MOST LIKELY BETWEEN MUNISING AND
GRAND MARAIS...FOR AN EXTENDED PERIOD OF TIME. LOW-END ADVISORY
AMOUNTS ARE POSSIBLE SUNDAY NIGHT THROUGH MONDAY WITH GENERALLY 3 TO
6 INCHES...THOUGH LOCAL AMOUNTS OF 8 INCHES ARE POSSIBLE. THE
NORTHERN EXTENT OF A WEAK SFC RIDGE WILL BACK WINDS ON TUESDAY AND
PUSH LES ACTIVITY OFF SHORE FOR MOST LOCATIONS.
A CONTINUOUS INFLUX OF H8 TEMPS AROUND -25C WILL BE PRESENT MONDAY
THROUGH TUESDAY AND BRING RATHER COLD CONDITIONS ACROSS THE AREA.
HOWEVER...TEMPS SHOULD REMAIN WARMER THAN WAS SEEN EARLIER IN THE
MONTH. ADDITIONALLY...WINDS WILL REMAIN MUCH LIGHTER EXCEPT ALONG
THE WARMER LAKE SHORES. STILL...WITH TEMPS FALLING TO THE TEENS
BELOW ZERO MONDAY NIGHT FOR THE INTERIOR WEST AND CENTRAL...A WIND
CHILL ADVISORY MAY BE NEEDED WITH CHILLS DOWN TO -30F.
WEDNESDAY INTO SATURDAY...YET ANOTHER POTENT CLIPPER WILL PUSH
SOUTHEAST RIGHT OVER THE CWA WEDNESDAY MORNING INTO THE AFTERNOON. A
QUICK ROUND OF MODERATE SNOW IS POSSIBLE FOR MUCH OF THE CWA
WEDNESDAY MORNING WITH IMPRESSIVE Q-VECTOR CONVERGENCE AND UPPER PV
ANOMALY. THE GFS HAS BEEN THE OUTLIER WITH THIS SYSTEM...SO HAVE
TRENDED WITH THE ECMWF AND GEM. BEHIND THE SYSTEM...INCREASING N TO
NE GRADIENT FLOW BETWEEN A LAGGING 1020 MB LAKE-INDUCED TROUGH AND
IMPINGING 1044 MB HIGH WILL BRING A POSSIBLY INTENSE BOUT OF LAKE
ENHANCED SNOW TO NORTH-CENTRAL UPPER MI. HAVE BUMPED UP POPS
CONSIDERABLY...AND LATER SHIFTS WILL NEED TO MONITOR MODEL TRENDS AS
HEADLINES WILL BE POSSIBLE WEDNESDAY AFTERNOON AND EVENING ALONG
LAKE SUPERIOR.
TEMPS CONTINUE TO REMAIN WELL BELOW NORMAL INTO THURSDAY AFTER
ANOTHER SHOT OF -25C H8 TEMPS WEDNESDAY AFTERNOON. DID NOT DEVOTE
MUCH TIME TO THE FORECAST BEYOND WEDNESDAY GIVEN MODEL DISAGREEMENT
AT THIS TIME...THOUGH WEIGHTED THE FORECAST TOWARD THE MORE
CONSISTENT ECMWF. INDICATIONS ARE THAT ANOTHER POTENT TROUGH AND
ACTIVE FEW DAYS OF WX WILL AFFECT THE AREA FRIDAY INTO SATURDAY
MORNING...WITH PERSISTENT LES FOR WNW SNOW BELTS THROUGH THE WEEKEND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1234 PM EST SAT JAN 18 2014
ARRIVAL OF DRIER LLVL AIR SHOWN ON 12Z INL RAOB UNDER SFC HI PRES
RDG WL RESULT IN PREDOMINANT VFR CONDITIONS AND LGT WINDS THRU THIS
EVNG. BUT SW WINDS WL BE INCRSG LATER TNGT AS PRES GRADIENT SHARPENS
TO THE S OF DEEPENING LO PRES TRACKING THRU ONTARIO. SN WL ALSO DVLP
BY THE EARLY MRNG HRS ON SUN AT IWD/CMX AHEAD OF APRCHG ATTENDANT
COLD FNT. THE COMBINATION OF THE FALLING AND BLSN WHIPPED UP BY THE
GUSTY WINDS WL LEAD TO IFR VSBYS...ESPECIALLY AT THE MORE EXPOSED
CMX LOCATION...WHERE LIFR CONDITIONS ARE LIKELY. DOWNSLOPE NATURE OF
THE EXPECTED WSW FLOW WL LIKELY MAINTAIN VFR WX AT SAW. STRONG
SUBSIDENCE AND DIMINISHING WINDS IN THE WAKE OF COLD FROPA ON SUN
MRNG SHOULD LIMIT THE INTENSITY OF LES/BLSN...BUT IFR VSBYS ARE
LIKELY TO PERSIST AT CMX. WSHFT TO A MORE UPSLOPE NNW DIRECTION WL
LEAD TO MVFR CONDITIONS AT SAW.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 446 PM EST SAT JAN 18 2014
RELATIVELY LIGHT WINDS EARLY THIS EVENING WILL GIVE WAY TO A WSW
GALE OVER MUCH OF CENTRAL AND EASTERN LAKE SUPERIOR OVERNIGHT AS THE
PRES GRADIENT TIGHTENS OVER THE UPPER LAKES S OF DEEPENING LO PRES
CROSSING ONTARIO. THE GALES WILL VEER TO THE NW ON SUN MORNING
FOLLOWING A COLD FRONTAL PASSAGE...BUT THE WINDS WILL TEND TO
DIMINISH TO 25-30 KTS DURING THE AFTERNOON WITH ARRIVAL OF WEAKER
PRES GRADIENT AHEAD OF APPROACHING HI PRES IN THE NORTHERN PLAINS.
DESPITE THE WEAKENING WINDS...ARRIVAL OF VERY COLD ARCTIC AIRMASS
WILL RESULT IN SOME HEAVY FREEZING SPRAY IN THE AFTERNOON OVER ABOUT
THE E HALF...SO STARTED THE HEAVY FREEZING SPRAY WARNING FOR THIS
AREA AT 18Z SUN. GOING GALE HEADLINE LOOKS TO BE IN GOOD SHAPE.
PERSISTENT NW FLOW OF 20 TO 30 KNOTS WILL CONTINUE THROUGH MONDAY
NIGHT BEFORE WINDS BACK AND WEAKEN IN RESPONSE TO THE NORTHERN
EXTENT OF A SFC RIDGE TUESDAY INTO TUESDAY NIGHT. A POTENT SYSTEM
TRACKING SE OVER UPPER MI WEDNESDAY MAY BRING N TO NE GALES ACROSS
MUCH OF THE LAKE WEDNESDAY AFTERNOON AND NIGHT. ANOTHER WEAK RIDGE
WILL DIMINISH AND BACK WINDS TO THE SW ON THURSDAY. THEN...SW GALES
TO 35 KNOTS WILL BE POSSIBLE THURSDAY NIGHT INTO FRIDAY AHEAD OF
ANOTHER STRONG TROUGH ACROSS SOUTH CENTRAL CANADA. 20 TO 30 KNOTS
WILL CONTINUE THROUGH SATURDAY WHILE VEERING TO THE NW.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING FROM 1 PM SUNDAY TO 7 AM EST
TUESDAY FOR LSZ251-267.
GALE WARNING FROM 11 PM THIS EVENING TO 4 PM EST SUNDAY FOR
LSZ249>251-266-267.
HEAVY FREEZING SPRAY WARNING FROM 1 PM SUNDAY TO 7 PM EST
TUESDAY FOR LSZ249-250-266.
HEAVY FREEZING SPRAY WARNING FROM 7 PM SUNDAY TO 1 PM EST
TUESDAY FOR LSZ244-245-248-264-265.
GALE WARNING FROM 11 PM THIS EVENING TO 7 AM EST SUNDAY FOR
LSZ265.
GALE WARNING FROM 8 PM THIS EVENING TO 7 AM EST SUNDAY FOR
LSZ242>245-263-264.
HEAVY FREEZING SPRAY WARNING FROM 7 PM SUNDAY TO 7 AM EST
TUESDAY FOR LSZ243-263.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...KLUBER
AVIATION...KC
MARINE...KC/KLUBER
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
348 PM CST SAT JAN 18 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 348 PM CST SAT JAN 18 2014
WEATHER HAS BEEN QUIETING DOWN QUICKLY IN THE WAKE OF THIS MORNINGS
STRONG CLIPPER. STRONG SUBSIDENCE IN THE WAKE OF THE CLIPPER HAS
HELPED CLEAR SKIES OUT...SAVE FOR A LINGERING ZONE OF FGEN AROUND H7
THAT HAS KEPT AN AREA OF CLOUDS WITH A FEW FLURRIES GOING FROM THE
TWIN CITIES BACK TOWARD EAU...THOUGH EVEN THESE CLOUDS SHOULD SLOWLY
FADE AWAY THIS AFTERNOON.
TONIGHT...WINDS WILL QUICKLY TURN TOWARD THE SW AS A MILD PACIFIC
AIRMASS QUICKLY MOVES INTO THE AREA. WAA OUT AHEAD OF THE WARM NOSE
WILL LEAD TO A BAND OF MAINLY MID LEVEL CLOUDS WORKING BACK ACROSS
THE AREA. HOWEVER...290-295K SFCS OFF THE NAM SHOWING ENOUGH
MOISTURE MAY BE PRESENT FOR ISENTROPIC LIFT IN THE FAR NE CWA TO
GENERATE SOME -SN AS THE WARMER AIRMASS MOVES IN. THIS IS SUPPORTED
BY REFLECTIVITY FORECASTS FROM THE HRRR AND OTHER HI-RES MODELS...SO
INTRODUCED SOME CHANCE POPS FOR THAT...THOUGH ONLY ONE OR TWO TENTHS
OF AN INCH OF SNOW WOULD BE LIKELY IF ANYTHING DOES FALL. THIS WAA
TONIGHT WILL RESULT IN ANOTHER NIGHT OF NON-DIURNAL TEMP
TRENDS...WITH TEMPS LIKELY ALREADY ABOVE 30 OFF THE BUFFALO RIDGE BY
SUNRISE SUNDAY...WITH MOST OF THE MN CWA INTO THE LOW/MID 20S BY THE
START OF THE DAY SUNDAY. THE WARM START MEANS THE MILD DAY STILL
LOOKS TO BE IN PLACE. FOLLOWED MORE THE GEM/ECMWF FOR HIGHS SUNDAY
WITH MOST OF THE AREA GETTING INTO THE LOW/MID 30S. IF YOU WOULD
LIKE TO AVOID THOUGHTS OF NEEDING A VACATION TO A WARMER CLIMATE...I
SUGGEST YOU STOP READING NOW...AS THESE HIGHS SUNDAY WILL NOT BE A
LASTING TREND.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 348 PM CST SAT JAN 18 2014
THE ROLLER COASTER RIDE OF TEMPERATURE TRENDS WILL CONTINUE
THROUGHOUT THE LONG TERM. AN ARCTIC FRONT WILL SAG SOUTH SUNDAY
NIGHT INTO CENTRAL MN AND WI. STEEP LAPSE RATES UP TO ABOUT 3KFT
IN STRONG CAA REGIME AND AN ISOTHERMAL MOIST TEMPERATURE PROFILE
WITHIN THE DGZ BETWEEN 3KFT TO 10KFT SHOULD PROMOTE OCCASIONAL
LIGHT SNOW DEVELOPMENT BEHIND THE FRONT UNTIL DRIER AIR WORKS IN
MONDAY AFTERNOON. BOOSTED POPS INTO THE CATEGORICAL RANGE...BUT
THIS LOOKS LIKE A HIGH CHANCE/LOW PRECIP EVENT WITH SNOWFALL
AMOUNTS REMAINING GENERALLY A HALF INCH OR LESS. THE BEST CHANCE
OF RECEIVING UP TO AN INCH WILL BE ACROSS WESTERN AND SOUTHERN MN
WHERE A VORTICITY MAX SLIDES SOUTHEAST IN ADVANCE OF THE BUILDING
SURFACE RIDGE MONDAY AFTERNOON. THIS WILL ENHANCE THE LIFT ENOUGH
TO GET A BIT MORE ROBUST SNOWFALL.
THE HIGH BUILDS INTO WESTERN MN MONDAY NIGHT. CLEARING SKIES AND
FRESH SNOWFALL WILL EASILY ALLOW FOR A STOUT INVERSION TO SET UP
WHICH SHOULD ALSO DECOUPLE THE WIND. IF THE WIND FULLY
DECOUPLES...TEMPERATURES WILL BE VERY COLD WITH WIDESPREAD 20S
BELOW ACROSS MN /EXCEPT FOR THE TWIN CITIES METRO/ AND TEENS BELOW
ACROSS WI. SOME SPOTS IN CENTRAL MN MAY DROP TO 30 BELOW AGAIN.
FORECASTING TEMPERATURES IN SUCH A SITUATION IS INHERENTLY
DIFFICULT AS LOCATIONS CAN VARY GREATLY WITH ENHANCED LOCAL
INFLUENCES. THEREFORE...CONFIDENCE IS NOT PARTICULARLY HIGH AND IT
IS IMPOSSIBLE TO CONVEY THESE HIGHLY VARIED LOCAL INFLUENCES WITH
MUCH PRECISION IN THE GRIDS. UNLIKE THE LAST COLD OUTBREAK...THE
COLDER MOS NUMBERS MAY NOT BE AS FAR OFF FROM REALITY IN THE
DECOUPLED ENVIRONMENT. TOOK A COMPROMISE OF THE MOS NUMBERS AND
THE BIAS CORRECTED MOS NUMBERS FOR TEMPS HOPING SPLITTING THE
DIFFERENCE WILL SUFFICE.
BY TUESDAY NIGHT...A WEAK DISTURBANCE WILL DROP SOUTHEAST INTO THE
GREAT LAKES. WITH IT WILL COME A NOSE OF WARMER AIR IN OVERNIGHT
AND A CHANCE OF SNOW ACROSS MUCH OF THE AREA.
THE NEXT ARCTIC FRONT WILL ARRIVE WEDNESDAY AND ANOTHER POLAR HIGH
WILL BUILD INTO THE DAKOTAS AND MINNESOTA WEDNESDAY NIGHT. IT WILL
BE A NEARLY IDENTICAL SET UP TO MONDAY NIGHT AND THE LOW TEMP GRID
IS QUITE SIMILAR AS WELL.
SOME UNCERTAINTY HAS BEEN INTRODUCED BY THE MIDDLE OF NEXT WEEK
WITH THE GFS SHOWING A MUCH MILDER SOLUTION COMPARED TO PREVIOUS
DAYS RUNS. IT SHOWS THE TROUGH BEING CONFINED TO NEW ENGLAND AND
AN EXPANSIVE ZONAL FLOW/WEAK RIDGING ACROSS THE REST OF THE CONUS.
PREFER THE MORE STABLE ECMWF SHOWING A CONTINUATION OF A SERIES OF
POLAR FRONTS THROUGH DAY 10. NOT SEEING MUCH TO INDICATE THE
CURRENT PATTERN WILL CHANGE AND GIVEN HOW LONG IT HAS PERSISTED
THIS WINTER...IT WILL TAKE QUITE A BIT MORE CONVINCING BEFORE A
CHANGE IN DIRECTION IS NECESSARY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1147 AM CST SAT JAN 18 2014
SNOW HAS ALL BUT MOVED OUT OF THE AREA WITH SKIES CLEARING IN THE
SUBSIDENCE IN THE WAKE OF THE LOW THAT IS NOW NEAR DSM. THOSE VFR
CONDITIONS WILL PREVAIL THROUGH MOST OF THIS TAF PERIOD AS ALL
MODELS SHOW STRIP OF MVFR CIGS OVER THE DAKOTAS NOT SURVIVING OUR
DRY AIR AS IT PUSHES EAST. NEXT ARCTIC COLD FRONT WILL BEGIN
SAGGING SOUTHWEST INTO THE MPX AREA AROUND 18Z SATURDAY...WITH
MVFR CIGS LIKELY RETURNING FOR A BIT IN ITS WAKE...THOUGH BETTER
CHANCES FOR MVFR CIGS LOOKS TO COME JUST AFTER THIS TAF PERIOD.
KMSP...HIGH CONFIDENCE IN TAF OVERALL. MODELS SHOW MVFR CIGS OVER
THE DAKOTAS TRACKING ACROSS NRN MN TONIGHT...WITH NOTHING MORE
THAN AN INCREASE IN MID LEVEL CLOUDS TONIGHT AS WARM BUBBLE FOR
SUNDAY MOVES IN. MAY SEE MVFR CIGS RETURN AT THE END OF THE
TAF...BUT CONFIDENCE TO LOW TO INCLUDE AT THIS TIME.
/OUTLOOK FOR KMSP/
MON...CHANCE MVFR/SN THRU MORNING. WINDS N 10KTS.
TUE...VFR. CHANCE MVFR CIGS/-SN TUE NIGHT. WINDS W-SW 5KTS.
WED...VFR. WINDS NW 10G20KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...MPG
LONG TERM...BORGHOFF
AVIATION...MPG
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
315 PM CST SAT JAN 18 2014
.UPDATE...
UPDATED TO ALLOW HIGH WIND WARNING EXPIRE.
&&
.DISCUSSION...
MOST SUSTAINED AND HIGH WIND GUSTS HAVE DROPPED BELOW HIGH WIND
WARNING CRITERIA...THUS ALLOWED TO EXPIRED AND HAVE THE WIND
ADVISORY GOING UNTIL 6PM.
&&
.PREV DISCUSSION... /ISSUED 1253 PM CST SAT JAN 18 2014/
UPDATE...
MAIN UPDATES WERE TO INCREASE WINDS AND ISSUE A HIGH WIND WARNING
FOR PARTS OF THE AREA.
DISCUSSION...
BY 1030AM...WE WERE STARTING TO GET A FEW HIGH WIND GUSTS AND
BASED ON EXPECTED STRENGTHENING DURING THE LATE
MORNING...FAVORABLE MOMENTUM TRANSFER OF WINDS ALOFT/STEEP LAPSE
RATES AND CONTINUED HIGH WINDS IN THE AFTERNOON...ISSUED A HIGH
WIND WARNING FOR SEVERAL COUNTIES IN NORTHEAST AND EAST CENTRAL
NEBRASKA. THE H9 WINDS SHOWED A LARGE AREA OF 50 TO 55KTS WINDS IN
THIS AREA AND THE RAP/HRRR WERE ALSO SUPPORTIVE OF HIGH WIND GUST.
THE LATEST HRRR IS EVEN A BIT MORE WIDESPREAD WITH THE STRONGER
WINDS.
AVIATION...
18Z TAFS FOR KOMA...KLNK...AND KOFK.
STRONG WINDS WILL BE THE PRIMARY AVIATION CONCERN THROUGH 00Z WITH
SUSTAINED WINDS OF 25-35KTS G40-50KTS. THE WINDS WILL SUBSIDE BY
00Z AND FURTHER DIMINISH TO UNDER 10KTS BY 03Z. THE BULK OF THE
PRECIP WAS TO THE SOUTH OF THE TAF SITES...WITH VFR CIGS
FL040-050. DO HAVE PERIODS OF MVFR CIGS ESPECIALLY AT KOFK AND
KOMA THROUGH THE AFTERNOON FL015-030.
PREV DISCUSSION... /ISSUED 337 AM CST SAT JAN 18 2014/
DISCUSSION...
THE MAIN FORECAST CONCERNS ARE THE WIND EVENT TODAY AND THEN NEAR
RECORD TEMPERATURES ON SUNDAY.
EARLY MORNING WATER VAPOR IMAGERY INDICATED A SMALL BUT POTENT
SHORTWAVE TROUGH OVER NE SD. THIS SYSTEM WAS ASSOCIATED WITH
AROUND 100 M H5 HEIGHT FALLS. THE ASSOCIATED 998 MB SURFACE LOW
ON THE 09Z OBJECTIVE SURFACE ANALYSIS WAS LOCATED OVER EXTREME SE
ND. THE UPPER LEVEL SYSTEM AND ASSOCIATED SFC LOW WILL BE DROPPING
SOUTH TODAY ACROSS SW MN EARLY THIS MORNING...AND THEN THROUGH
IOWA THIS AFTERNOON. CONSISTENT WITH PREVIOUS SYSTEM THIS
WEEK THE LARGE-SCALE FORCING FOR ASCENT AND MEASURABLE PRECIP
WILL MISS OUR FA TO THE EAST...BUT OUR CWA WILL ONCE AGAIN BE IN A
FAVORABLE LOCATION FOR STRONG WINDS. MODELS ALL REMAIN CONSISTENT
IN THE 7-8 MB 3 HR SURFACE PRESSURE RISES /CURRENTLY OVER NORTHERN
ND/ WILL PUSH INTO THE FA THROUGH THE MORNING AS THE SURFACE
LOW MOVES INTO IOWA. THE 850 AND 925 MB WINDS INCREASE TO 50-55
AND 40-45 KT RESPECTIVELY. THIS ALONG WITH STEEPING LOW LEVEL
LAPSE RATES WILL ALLOW FOR STRONG WINDS TO MIX TO THE SURFACE.
PREVIOUSLY ISSUED WIND ADVISORY FOR THE ENTIRE CWA LOOKS GOOD. WE
MAY SEE A COUPLE OF LOCATIONS /SUCH AS OFK-BVN-OLU/ FLIRT WITH
HIGH WIND WARNING FOR AN HOUR WITH WIND GUSTS AS THE BEST PRESSURE
RISES MOVE THROUGH. WILL HAVE SOME GUSTS TO 48 KT FOR THESE
LOCATIONS BUT WIDESPREAD WRNG CRITERIA WINDS ARE NOT EXPECTED. AS
WITH THE THURSDAY SYSTEM...WE WILL LIKELY SEE ISO-SCT SNOW SHOWERS
DEVELOP WITH THE STEEP LOW-LEVEL LAPSE RATES AND SMALL POSITIVE
AREA IN POINT FORECAST SOUNDINGS. WE DO NOT EXPECT ANY
ACCUMULATION OR BLOWING SNOW ISSUES HERE...BUT WILL MAINTAIN THESE
SMALL POPS THROUGH EARLY AFTERNOON BEFORE THE SOUNDINGS START TO
STABILIZE.
THE CONDITIONS WILL QUIET RAPIDLY BY LATE AFTERNOON AND THE WIND
ADVISORY MAY BE ABLE TO BE CANCELLED EARLIER THAN ITS CURRENT 6
PM TIME FRAME AS THE SYSTEM SHIFTS EAST AND THE LOW LEVEL FLOW
BACKS TO THE WEST. THIS SHOULD SET UP A VERY FAVORABLE PATTERN FOR
WARMING ON SUNDAY. MODELS CONTINUE TO INITIALIZE WITH SNOW COVER
OVER THE ERN 2/3 OF THE FA AND THIS IS IN ERROR AND THUS GRIDDED
AND MOS PRODUCTS ARE WAY TO COOL WITH TEMPERATURES. MIXING TO
AROUND 925 MB PRODUCED HIGHS IN THE 60S WEST AND 50S EAST. WE WILL
LIKELY FALL SHORT OF RECORDS AT ALL 3 SITES THOUGH BUT STILL WELL
ABOVE NORMAL.
TEMPERATURES ARE THE MAIN FORECAST CONCERN THROUGH THE EXTENDED
PERIOD AS A BACK DOOR COLD FRONT PUSHES INTO THE FA ON MONDAY. THE
MODELS ARE A TOUCH SLOWER WITH THIS FRONT THAN PREVIOUS RUNS AND
THUS WE MAY SEE TEMPERATURES WARM THROUGH THE FIRST HALF OF MONDAY
BEFORE FALLING IN THE AFTERNOON. THUS WE HAVE INCREASED HIGHS
MOST AREAS FOR MONDAY. BOTH THE NAM AND GFS ADVERTISE STRONG 925
MB FRONTOGENESIS AS THIS BOUNDARY SLIDES INTO THE FA AND THIS MAY
ALLOW FOR SOME LIGHT SNOW SHOWERS AGAIN LATE MONDAY AFTERNOON IN
THE NORTH...CONTINUING INTO THE EVENING HOURS BUT AGAIN WE DO NOT
EXPECT ACCUMULATIONS. THIS BOUNDARY WILL OSCILLATE ACROSS THE FA
THROUGH THE REST OF THE EXTENDED. WED NIGHT AND THU LOOK TO BE THE
COLDEST PERIODS OF THE EXTENDED BEFORE TEMPERATURES START TO
MODERATE TOWARD NEXT WEEKEND.
BOUSTEAD
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR NEZ011-012-015>018-
030>034-042>045-050>053-065>068-078-088>093.
IA...WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR IAZ043-055-056-069-
079-080-090-091.
&&
$$
ZAPOTOCNY
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
323 PM EST SAT JAN 18 2014
.SYNOPSIS...
A SERIES OF DISTURBANCES IN THE JET STREAM WINDS ALOFT AND
ASSOCIATED COLD FRONTS WILL PRODUCE PERIODS OF SNOW SHOWERS ALONG
WITH MUCH COLDER TEMPERATURES BY EARLY THIS UPCOMING WEEK.
OVERALL...SNOW ACCUMULATIONS WILL BE LIGHT WITH BEST CHANCES OF A
COUPLE INCHES OCCURRING ACROSS THE ADIRONDACK MOUNTAINS OF NEW YORK
AND NORTHERN GREEN MOUNTAINS OF VERMONT. TEMPERATURES WILL BE ABOVE
NORMAL AGAIN ON SUNDAY...BUT FALL BETWEEN 10 AND 20 DEGREES BELOW
NORMAL BY TUESDAY.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
AS OF 320 PM EST SATURDAY...FCST CHALLENGE TONIGHT WL BE AREAL
COVERAGE/INTENSITY OF SNOW...ALONG WITH CLOUDS AND IMPACTS ON
TEMPS. WATER VAPOR SHOWS POTENT 5H VORT DRIVING ACRS THE OHIO
VALLEY WITH MID LVL MOISTURE STREAMING AHEAD OF SYSTEM ACRS
CENTRAL/WESTERN NY/PA ATTM. HOWEVER...SATL PICS SHOW CLOUDS
INCREASING ACRS THIS REGION...BUT OBSERVATIONS SHOW LIMITED
MOISTURE/SNOW REACHING THE GROUND...INDICATING VERY DRY LLVLS.
THIS WL BE OUR FCST PROBLEM TONIGHT. HIGH RESOLUTION BTV4KM...RAP
13...AND 15Z HRRR MODEL SHOW WEAK INVERTED TROF LIKE FEATURE WITH
SOME LEFTOVER MID LVL MOISTURE/LIFT MOVING FROM SOUTH TO NORTH
ACRS OUR CWA BTWN 02Z-08Z TONIGHT. IN ADDITION...925MB TO 850MB
WINDS BECOME NORTHWEST WHICH WL HELP ENHANCE LLVL
LIFT/MOISTURE...BUT OVERALL QPF IS VERY LIGHT <.10" WITH GREATEST
FOCUS ACRS THE NORTHERN DACKS AND CENTRAL GREEN MTNS. WL MENTION
LIKELY POPS OVERNIGHT IN THE MTNS...AND JUST CHC POPS IN THE
VALLEYS WITH A DUSTING TO 1 INCH POSSIBLE. BASED ON GOOD OMEGA/RH
AND SNOW GROWTH PROFILES...WOULD NOT BE SURPRISED OF A DUSTING OR
SO OVERNIGHT AT BTV. TEMPS WL HIGHLY DEPEND UPON
CLOUDS/PRECIP...BUT WL TREND WARMER BASED ON PROGGED RH
FIELDS...L20S MTN VALLEYS TO M/U 20S ELSEWHERE. OTHERWISE...RAP 13
SHOWS BETTER 1000 TO 500 MB RH >70% APPROACHING OUR WESTERN CWA BY
10Z SUNDAY...ASSOCIATED WITH NEXT CLIPPER SYSTEM. WL INCREASE POPS
ACRS OUR WESTERN CWA TWD SUNRISE...BUT BETTER PRECIP CHCS ARRIVE
ON SUNDAY.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/...
AS OF 356 AM EST SATURDAY...NE CONUS WL BE IN TRANSITION FROM ABOVE
NORMAL TEMPS TO DEVELOPING DEEP MID/UPPER LVL TROF WITH MUCH BLW
NORMAL TEMPS ANTICIPATED BY EARLY THIS UPCOMING WEEK. NAM/GFS ARE
IN GOOD AGREEMENT WITH LARGE SCALE FEATURES...AND SHOW SYSTEMS WL
BE COMING IN PIECES. BOTTOM LINE WL BE EACH EMBEDDED 5H VORT AND
ASSOCIATED SFC TROF WL HAVE LESS AND LESS AVAILABLE MOISTURE TO
WORK WITH...ESPECIALLY AS ARCTIC AIR BECOMES ESTABLISHED BY
MONDAY. IN ADDITION...HAVE NOTED BEST 5H PVA ASSOCIATED WITH
POTENT S/W ENERGY SLIDES TO OUR SOUTH ON SUNDAY...WHILE A RIBBON
OF ENHANCED 850 TO 500MB RH RACES FROM THE NORTHERN OHIO VALLEY
INTO THE NE CONUS. MEANWHILE...BEST LLVL SFC CONVERGENCE WITH
ARCTIC BOUNDARY LAGS ACRS THE NORTHERN LAKES ON SUNDAY AND DOES
NOT ARRIVE UNTIL EARLY MONDAY...WHEN BEST RH IS SHIFTING SOUTH OF
OUR CWA. FOR SUNDAY...WL MENTION LIKELY/CAT POPS ACRS THE
DACKS/SOUTHERN SLV AND PARTS OF THE CENTRAL/NORTHERN GREEN MTNS.
ELSEWHERE WL MENTION CHC/LOW LIKELY POPS BASED ON FAVORABLE 850 TO
500MB RH PROFILES AND SOME WEAK MID LVL LIFT. OVERALL...QPF WL BE
LIGHT...RANGING FROM A COUPLE HUNDREDTHS TO A COUPLE TENTHS ACRS
THE NORTHERN GREENS AND WESTERN DACKS. SNOW ACCUMULATIONS WL BE A
DUSTING TO 2 OR 3 INCHES. HAVE NOTED THE SNOW SQUALL PARAMETER
INCREASES DURING THE AFTN HOURS...THINKING THIS IS A RESULT OF SFC
HEATING AND STEEPENING LLVL LAPSE RATES/INSTABILITY...WHICH HINTS
AT SNOW SHOWER ACTIVITY BECOMING MORE CONVECTIVE IN NATURE. SOME
UNCERTAINTY ON SNOW SQUALLS AS BEST CONVERGENCE/925MB FGEN ARRIVES
AFT 21Z SUNDAY WITH ARCTIC BOUNDARY...THEREFORE WL NOT MENTION
SQUALLS ON SUNDAY...BUT COULD SEE BRIEF MODERATE SNOW SHOWER
ACTIVITY ACRS THE MTNS. THE COMBINATION OF COOLING 925MB TEMPS AND
MORE CLOUDS ANTICIPATED...THINKING HIGHS WL RANGE BTWN M/U 20S
MTNS TO L/M 30S WARMER VALLEYS ON SUNDAY.
SUNDAY NIGHT INTO MONDAY...WELL ADVERTISED ARCTIC BOUNDARY SWINGS
ACRS OUR CWA...WITH RIBBON OF ENHANCED MOISTURE AND STRONG 925MB
FGEN FORCING. IN ADDITION...LOCAL 4KM WRF AND LATEST 12Z NAM SHOW
FAVORABLE CONDITIONS FOR SNOW SQUALLS AS LOCALLY DEVELOPED SNOW
SQUALL PARAMETER IS BTWN 3-5...ESPECIALLY ACRS NORTHERN CWA...WHERE
INSTABILITY/MOISTURE AND WIND FIELDS ARE THE BEST. HOWEVER...STILL
SOME UNCERTAINTY ON AREAL COVERAGE OF SNOW SHOWERS AND POTENTIAL OF
SNOW SQUALLS AS BEST CONVERGENCE/SHARP THERMAL BOUNDARY LAGS
MOISTURE/FORCING. THINKING ANOTHER DUSTING TO LOCALIZED 2 OR 3
INCHES WL BE POSSIBLE ON SUNDAY EVENING...WITH HIGHEST AMOUNTS IN
THE MTNS. AFTER 06Z MONDAY...BEST CONVERGENCE AND MOISTURE QUICKLY
SHIFTS SOUTH OF OUR CWA AND DRIER AIR ADVECTS ON BRISK NORTHWEST
WINDS. A FEW LINGERING UPSLOPE SNOW SHOWERS/FLURRIES WL BE POSSIBLE
BUT OVERALL PRECIP WL BE LIGHT. WL MENTION LIKELY POPS ASSOCIATED
WITH BOUNDARY THRU 06Z...THEN TAPER TO CHC POPS FOR THE MTNS BY 12Z
MONDAY. STRONG LLVL CAA DEVELOPS WITH PROGGED 925MB TEMPS RANGING
BTWN -8C NEAR VSF TO -20C NEAR MSS AT 12Z MONDAY. THESE TEMPS CONT
TO FALL ON MONDAY ON BRISK NORTHWEST WINDS OF 10 TO 20 KNOTS WITH
VALUES BTWN -14C AND -23C BY 00Z TUES. TEMPS WL STRUGGLE IN THE
SINGLE DIGITS SLV/DACKS TO L/M 20S LWR CT RIVER VALLEY ON MONDAY.
MONDAY NIGHT...SFC HIGH PRES AXIS BUILDS INTO OUR CWA...BUT GRADIENT
REMAINS BTWN BUILDING HIGH PRES AND DEPARTING LOW PRES. THIS WL
CREATE BRISK NORTHWEST WINDS...ESPECIALLY IN THE EVENING HRS AND
BITTERLY COLD WIND CHILL VALUES. THINKING WIND CHILL
ADVISORIES/WARNINGS WL PROBABLY BE NEEDED FOR READINGS BTWN -15F TO
-30F. SFC TEMPS WL RANGE BTWN -15 AND -20F SLV/DACKS TO 0F TO -10F
ACRS MOST OF VT...WITH WARMEST VALUES NEAR LAKE CHAMPLAIN AND ACRS
THE LWR CT RIVER VALLEY.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 205 PM EST SATURDAY...OVERALL QUIET WEATHER EXPECTED FOR
THE LONG TERM...WITH RIDGING OVER THE NORTH COUNTRY KEEPING
COASTAL LOW AND ASSOCIATED PRECIP FAR TO THE EAST. WITH NW FLOW
FILTERING IN COLDER AIR AS 925MB TEMPS DROP INTO THE -20C TO -28C
RANGE. THIS WILL RESULT IN TUESDAY AND WEDNESDAY MAX TEMPS IN THE
SINGLE DIGITS WITH HIGHER ELEVATIONS SEEING MAX TEMPS NEAR ZERO
OR SLIGHTLY COOLER. TUESDAY NGT AND WEDNESDAY NGT MIN TEMPS WILL
RANGE FROM NEGATIVE TEENS TO NEGATIVE SINGLE DIGITS.
SOME SLGT WARMING PSBL ON THURSDAY AS A WEAKENING SFC LOW MOVES
FROM THE SERN GREAT LAKES TO OUR SOUTH TOWARDS THE
ATLANTIC...KEEPING THE NORTH COUNTRY DRY...BUT ALSO BRINGING A
BRIEF BREAK IN NORTHERLY FLOW. TEMPS ON THURSDAY WILL RANGE FROM
0 TO LOW TEENS DURING THE DAY WITH THURSDAY NGT MINS IN THE
NEGATIVE SINGLE DIGITS.
BEHIND THIS WEAKENING SFC LOW...RIDGING WILL OCCUR AT THE SFC AND
ALOFT. AS THE SFC RIDGE AXIS SHIFTS EAST...BRINGING SOUTHERLY
FLOW TO THE NORTH COUNTRY...TEMPS WILL MODERATE TO THE TEENS ON
FRIDAY...POSITIVE DIGITS FRIDAY NIGHT AND WARMING TO NEAR NORMAL
ON SATURDAY.
EVEN THOUGH THE NORTH COUNTRY WILL GENERALLY BE IN NW FLOW
TUESDAY THROUGH THURSDAY...LACK OF MOISTURE AND STRONG FLOW WILL
INHIBIT POTENTIAL FOR UPSLOPE SNOW SHOWERS. THE NEXT PROBABLE
CHANCE FOR WIDESPREAD PRECIP WILL BE AT THE END OF THE PERIOD
FRIDAY NGT AS AN UPPER LOW BRINGS VORTICITY TOWARDS THE NORTH
COUNTRY FROM THE NW FRIDAY NGT INTO THE WKND.
&&
.AVIATION /21Z SATURDAY THROUGH THURSDAY/...
THROUGH 18Z SUNDAY...LIGHT FLOW CONTINUES WITH VFR CONDITIONS
THIS AFTN. DRY AIR ACROSS THE NORTH COUNTRY KEEPING MOISTURE AT
BAY...BUT LATE THIS AFTN INTO EARLY EVENING...EXPECT -SHSN TO
AFFECT TERMINALS BRIEFLY. AREAS MOST LIKELY TO SEE -SHSN AND MVFR
CONDITIONS WITHIN -SHSN WILL BE KMSS/KRUT/KMPV AND KSLK. AFTER
03Z...SNOW SHOWERS LOOK TO DIMINISH AS FEATURE TO THE WEST
WEAKENS AND LOW OFF THE NEW ENGLAND COAST SHIFTS NORTHEASTWARD.
EXPECT VFR CONDITIONS AFTER SNOW SHOWERS MOVE OUT...BUT ANY
CLEARING COULD LEAD TO FOG DEVELOPMENT ESP IN LGT FLOW LESS THAN
5KTS.
TOWARDS DAYBREAK...INCREASING CHC FOR -SHSN ESP AT KMSS/KSLK AS
SW FLOW DEVELOPS. ANOTHER SFC LOW PRESSURE SYSTEM WILL APPROACH
FROM THE NW...INCREASING THREAT FOR SHSN ACROSS THE NORTH COUNTRY
AROUND 12Z AND AFTER. WINDS GENERALLY OUT OF THE SOUTH AT
5-10KTS.
OUTLOOK 18Z SUNDAY THROUGH THURSDAY...
18Z SUN THROUGH 12Z MONDAY...VFR WITH SCT MVFR/IFR IN SHSN AS
ARCTIC FRONT PUSHES THROUGH THE AREA. BEST SHSN COVERAGE 18-06Z.
12Z MONDAY ONWARD...MAINLY VFR WITH HIGH PRESSURE.
&&
.EQUIPMENT...
AS OF 400 AM EST SATURDAY...THE KTYX 88D DOPPLER RADAR LOCATED IN
NORTHERN NEW YORK REMAINS OUT OF SERVICE DUE TO A FAILED POWER
SUPPLY. PARTS ARE ON ORDER TO REPAIR THE PROBLEM BUT IT WILL
LIKELY BE OUT OF SERVICE THROUGH AT LEAST TUESDAY JANUARY 21.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...TABER
NEAR TERM...TABER
SHORT TERM...TABER
LONG TERM...KGM
AVIATION...KGM
EQUIPMENT...WFO BTV
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1100 AM CST SAT JAN 18 2014
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 312 AM CST SAT JAN 18 2014
MAIN FORECAST CONCERN THROUGH THE SHORT TERM CENTERED ON
ACCUMULATING SNOW TODAY.
WATER VAPOR/SURFACE ANALYSIS SHOW VIGOROUS LOW PRESSURE MOVING OUT
OF EASTERN ND SOUTHEAST INTO MN. RADAR AND SURFACE OBSERVATIONS
SHOWING AN EXPANSIVE NW-SE BAND OF LIGHT TO MODERATE SNOWFALL IN
ADVANCE OF THE LOW AND ATTENDANT WARM FRONTAL BOUNDARY EXTENDING
ACROSS MOST OF MN. INDICATION OF THE STRONG BAROCLINICITY ASSOCIATED
WITH THIS WAVE EVIDENCED BY TEMPERATURES RANGING FROM THE 30S ACROSS
THE DAKOTAS TO READINGS ONLY IN THE SINGLE DIGITS ABOVE AND BELOW
ZERO ACROSS THE NWS LA CROSSE FORECAST AREA.
MODELS ALL HONED INTO PROGGED TRACK OF THE LOW...TAKING IT SOUTHEAST
INTO SOUTH CENTRAL MN BY 12Z AND THEN INTO CENTRAL IL BY SUN 00Z.
DYNAMICS FAIRLY IMPRESSIVE WITH THE SYSTEM WITH STRONG ISENTROPIC
LIFT INDICATED BY RAP ON THE 275K SURFACE AND WEAK TO MODERATE
FRONTOGENETIC FORCING IN THE 1000-700MB LAYER. BUFKIT ALSO SHOWING
AROUND 17 MICROBARS OF LIFT THROUGH THE DENDRITIC GROWTH ZONE AT
KRST EARLY ON THIS MORNING. SNOW TO LIQUID RATIOS SHOULD BE FAIRLY
HIGH AS A RESULT...SOMEWHERE IN THE 16-18 TO 1 RANGE. GIVEN THIS AND
THE TRACK OF THE LOW...HEAVIEST SNOW BAND WILL SET UP ALONG AN AXIS
FROM DODGE CENTER AND ROCHESTER THROUGH DUBUQUE IA WHERE AROUND 4 TO
LOCALLY 5 INCHES IS EXPECTED THROUGH THE DAY. AS A RESULT...A WINTER
WEATHER ADVISORY REMAINS IN EFFECT UNTIL 6 PM THIS EVENING FOR ALL
OF SOUTHEAST MN/NORTHEAST IA..AND COUNTIES IN WI BORDERING THE
MISSISSIPPI AND WISCONSIN RIVERS. LOOKS LIKE MOST OF THE
ACCUMULATING SNOW MAY BE DONE/SHIFTED SOUTHEAST OF THE AREA BEFORE
6PM...BUT SOME DRIFTING OF THE SNOW WITH INCREASING NORTH WINDS ON
THE BACKSIDE OF THE LOW MAY STILL CAUSE SOME DRIVING
DIFFICULTIES...SO WILL LET IT UP THE THE DAYSHIFT TO ASSESS THE
STATUS OF THE ADVISORY HEADLINE GOING INTO THE AFTERNOON.
OTHERWISE...TEMPERATURES TODAY EXPECTED TO MODERATE INTO THE UPPER
TEENS TO MIDDLE 20S.
A RIDGE OF HIGH PRESSURE MOVES ACROSS THE AREA TONIGHT WITH WARM AIR
ADVECTION KICKING IN AFTER MIDNIGHT. LOOK FOR LOWS OCCURRING AROUND
MIDNIGHT IN THE UPPER SINGLE DIGITS/LOWER TEENS...THEN SLOWING
CLIMBING THROUGH THE TEENS AFTER MIDNIGHT.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 312 AM CST SAT JAN 18 2014
MILDER DAY ON TAP FOR SUNDAY AS WARM AIR ADVECTION CONTINUES IN
ADVANCE OF A COLD FRONT MOVING SOUTHWARD OUT OF CANADA INTO NORTHERN
WI. LOOK FOR HIGHS TOPPING OFF IN THE MIDDLE 20S TO THE MIDDLE 30S.
THE COLD FRONT WILL CONTINUE MOVING SLOWLY SOUTHWARD ACROSS THE AREA
SUNDAY NIGHT AS A WEAK MID-LEVEL WAVE RIPPLES ALONG THE BAROCLINIC
ZONE IN PLACE. THIS WILL GIVE THE AREA A CHANCE FOR SOME VERY LIGHT
SNOWFALL.
THE COLD FRONT WILL ALSO MARK THE TRANSITION BACK TO COLDER THAN
NORMAL NORTHWEST FLOW GRIPPING THE REGION AGAIN. MODELS ALSO SHOW
VARIOUS EMBEDDED SHORTWAVE TROUGHS WITHIN THE FLOW FOR ON/OFF LIGHT
SNOW CHANCES THROUGH FRIDAY. CONFIDENCE ON TIMING THESE WAVES PRETTY
LOW AT THIS TIME WITH VARIOUS MODEL SOLUTIONS. OTHERWISE...LOOK FOR
HIGH TEMPERATURES GENERALLY IN THE SINGLE DIGITS AND TEENS ABOVE
ZERO WITH LOWS IN THE SINGLE DIGITS AND TEENS BELOW ZERO. APPEARS
WIND CHILL HEADLINES WILL LIKELY BE NEEDED MONDAY NIGHT/TUESDAY
MORNING AS WIND CHILL VALUES DIP INTO THE 20S TO NEAR 30 BELOW ZERO.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1100 AM CST SAT JAN 18 2014
SNOW HAS ENDED FOR KRST...BUT COULD LINGER UNTIL 19-20Z AT KLSE.
DON/T EXPECT MUCH ACCUMS AT KLSE AFTER 18Z THOUGH...AND VSBYS AND
CIGS WILL BE ON AN IMPROVING TREND.
LATEST SATELLITE IMAGERY/SFC OBS SHOW CLEAR SKIES OVER MOST OF
CENTRAL/NORTHERN MN...ROTATING SOUTHEAST. CLOUDS STILL HANGING
ACROSS NORTHWEST WI...BUT GENERALLY VFR. STRONG SUBSIDENCE POST THE
LOW PRESSURE SYSTEM WAS RESPONSIBLE FOR THE CLEARING OVER MN...AND
EXPECT A PERIOD OF SCT/SKC LATER THIS AFTERNOON - PERSISTING INTO
THE EVENING. TRENDS ALSO FAVOR VFR CIGS FOR THE REST OF TODAY AND
TONIGHT. THAT SAID...MODELS WANT TO HANG ONTO SOME LOW SATURATION
PER RH FIELDS AND BUFKIT SOUNDINGS TONIGHT. SOME MVFR CIGS OVER THE
NORTHERN PLAINS...BUT THINK THAT WILL SINK SOUTH/SOUTHEAST...AWAY
FROM THE TAF SITES. SO GOING TO LEAN ON THE OPTIMISTIC-SIDE FOR THE
TAFS.
WINDS WILL INCREASE FROM THE SOUTHWEST TONIGHT...BECOMING MORE WEST
ON SUNDAY. SOME MID LEVEL CLOUDS WILL ALSO RETURN LATER
TONIGHT...AHEAD OF A SHORTWAVE TROUGH TRACKING ACROSS SOUTHERN
CANADA.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR WIZ032-
033-041-053>055-061.
MN...WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR MNZ079-
086>088-094>096.
IA...WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR
IAZ008>011-018-019-029-030.
&&
$$
SHORT TERM...DAS
LONG TERM....DAS
AVIATION.....RIECK