Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 01/07/15
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
124 PM MST MON JAN 5 2015
.UPDATE...
ISSUED AT 123 PM MST MON JAN 5 2015
THE PULSY NATURE OF CHINOOK WINDS CONTINUES TO PLAY GAMES WITH
TODAY/S FORECAST. FOR INSTANCE MANY AREAS IN THE FRONT RANGE
FOOTHILLS HAVE BEEN GUSTING FROM THE WEST-NORTHWEST AT 30-45KTS
WITH HIGHER GUSTS TO AROUND 75KTS AT TIMES. WHILE OTHER AREAS ONLY
5-15KTS FROM THE SOUTH-SOUTHWEST. A SIMILAR SITUATION IS
OCCURRING ON THE NEARBY PLAINS. CASE IN POINT...WESTERLY WINDS AT
DIA HAVE BOUNDED BACK AND FROM 10 TO 24 MPH PAST COUPLE OF HOURS
WITH A PEAK GUST TO 38 MPH JUST THIS PAST HOUR. ONCE WINDS KICKED
IN ALONG THE FOOTHILLS TEMPERATURES SOARED AS MUCH AS 30 DEGS F.
WHERE WINDS WERE BLOWING ON THE PLAINS CURRENT TEMPS IN THE UPPER
40S TO MID 50S. WHEREAS FARTHER OUT ON THE PLAINS WHERE WINDS ARE
LIGHT AND VARIABLE...READINGS ARE STRUGGLING TO CLIMB OUT OF THE
TEENS. HOWEVER IN THE NEXT COUPLE OF HOURS...MESOSCALE MODELS SHOW
GUSTY NWLY WINDS BLOWING DOWN OFF THE CHEYENNE RIDGE. SHOULD THIS
OCCUR...PRESUMABLY WE SEE QUICK MIXING OF THE BNDRY LAYER
RESULTING IS A SPIKE IN TEMPS...MAINLY UP ALONG THE WYOMING AND
NEBRASKA BORDERS. UPDATED TEMPERATURE AND WINDS GRIDS TO BETTER
REFLECT THE GUSTY NATURE OF THE WINDS AND THE BITTER COLD AIR
TRAPPED ALONG THE SOUTH PLATTE RIVER. ALSO BEEFED UP POPS AND SNOW
AMOUNTS IN THE NRN MTNS FOR THE REST OF TODAY WHERE ANOTHER 2-4
INCHES OF SNOW POSSIBLE RIDGETOPS AND NW FACING SLOPES BY THIS
EVENING.
UPDATE ISSUED AT 943 AM MST MON JAN 5 2015
WINDS WILL CONTINUE TO HOWL IN THE HIGH COUNTRY AND ACROSS
NORTHERN PORTIONS OF SOUTH PARK FOR THE REMAINDER OF TODAY.
SEVERAL FRONT RANGE WIND SENSORS HAVE ALREADY MEASURED GUSTS IN
THE 70 TO 80 MPH RANGE. THE STRONGEST WIND GUST MEASURED THUS FAR
WAS 85 MPH AT THE GOLD HILL SITE JUST WEST OF BOULDER. THE 109 MPH
WIND GUST RECORDED DURING THE PAST SEVERAL HOURS AT THE KENOSHA
PASS WIND SENSOR IS IN ERROR. FOR SOME REASON THIS SENSOR LOCKS ON
109 MPH WHENEVER THERE`S STRONG WINDS...BLOWING SNOW AND/OR VERY
COLD TEMPERATURES AT THAT SITE.
THESE POTENTIALLY DAMAGING AND VERY GUSTY WEST WINDS ARE EXPECTED
TO BECOME MORE WIDESPREAD IN THE FRONT RANGE MOUNTAINS AND
FOOTHILLS BY LATE THIS MORNING WITH PEAK GUSTS TO AROUND 85 MPH
EXPECTED THROUGH LATE THIS AFTERNOON. THE STRONG WINDS ARE LIKELY
TO PRODUCE CONSIDERABLE BLOWING AND DRIFTING SNOW IN OPEN AREAS.
WINDS ARE EXPECTED TO DECREASE IN SPEED BY MID TO LATE THIS
EVENING. THAT SAID...WEST WINDS OF 25-40 AND GUSTS TO AROUND 60
MPH ACROSS NORTHERN PORTIONS OF SOUTH PARK HAS PROMPTED A BLOWING
SNOW ADVISORY FOR ZONE 37. ADVISORY GOES UNTIL 5 PM MST TODAY.
CDOT CAMS CLEARLY INDICATE QUITE A BIT OF BLOWING SNOW ALONG U.S.
HIGHWAY 285 NORTH OF FAIRPLAY.
ELSEWHERE...STRONG WESTERLY WINDS ARE JUST OFF THE SFC BASED ON
KFTG WIND PROFILER...ACARS WIND PLOTS AND LATEST RAP WIND DATA.
ANOTHER INDICATION OF THESE STRONG WINDS CAN BE SURMISED BY THE
RAPID RISE IN TEMPERATURE AT DIA IN THE PAST HOUR WHERE IT ROSE
FROM 17F TO 41F. SUSPECT ITS ONLY A MATTER OF TIME BEFORE GUSTY
WARM CHINOOK WINDS WILL MIX DOWN ACROSS PORTIONS OF THE I-25
URBAN CORRIDOR AND WRN PORTIONS OF THE PALMER DIVIDE. ITS ALREADY
IN THE LOW/MID 40S ON THE PALMER DVD IN DOUGLAS COUNTY.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT )
ISSUED AT 345 AM MST MON JAN 5 2015
MAIN CONCERN TODAY AND THIS EVENING IS THE HIGH WIND POTENTIAL IN
THE MOUNTAINS AND FOOTHILLS. CURRENT OBSERVATIONS SHOWING WINDS
BEGINNING TO INCREASE BUT STILL ONLY IN THE 30-45 MPH RANGE. 88D
ALSO SHOWING WIND SIGNATURE INCREASING IN THE PAST HOUR AS WINDS
BEGIN TO DESCEND THROUGH THE FOOTHILLS OF BOULDER COUNTY. SURFACE
PRESSURE ALSO BEGINNING TO FALL BUT BEST PRESSURE FALLS STILL
OVER MONTANA AND WYOMING. SURFACE PRESSURE GRADIENT WILL CONTINUE
TO STEEPEN ACROSS THE STATE AS THE ADDITIONAL FALLS WORK INTO
EASTERN COLORADO. LATEST MODELS SHOWING SURFACE GRADIENT TO
TIGHTEN TO AROUND 15 MB FROM GJT TO DEN BY LATER THIS AM AND
THROUGH THE AFTERNOON.
CROSS SECTIONS SHOWING 60-70KT CROSS BARRIER FLOW DEVELOPING THIS
MORNING BEFORE DECREASING THIS EVENING. STRONG MID LEVEL WARMING
WILL RESULT IN STRONG INVERSIONS DEVELOPING AT MOUNTAIN TOP LEVEL
ALONG WITH ADEQUATE WIND SHEAR PROFILE FOR AMPLIFIED MOUNTAIN
WAVE. THE ONE FACTOR AGAINST HIGH WINDS TODAY IS THE INCREASED
MOISTURE AND LIGHT SNOW EXPECTED OVER HIGHER NORTHERN MOUNTAINS.
LATEST RAP/HRRR SHOWING PEAK WIND GUSTS IN THE 60-80KT RANGE FROM
16Z-23Z. FEEL THERE ENOUGH CONFIDENCE TO UPGRADE THE WATCH TO A
WARNING FOR THE MOUNTAINS AND FOOTHILLS. WINDS MAY HAVE A HARD
TIME DEVELOPING ACROSS LOWER ELEVATIONS OF THE FOOTHILLS BUT
BELIEVE THE STRONG GRADIENT WILL AID IN THE WIND DEVELOPMENT.
EXPECT LIGHT SNOW TO DEVELOP OVER FAR NORTHERN MOUNTAINS TODAY BUT
EXPECT SNOWFALL AMOUNTS WILL BE ON THE LIGHT SIDE DUE TO LOW
LAPSE RATES DESPITE THE STRONG OROGRAPHIC FLOW. BEST SNOWFALL
LIKELY WILL BE OVER ZONE 31 WITH UP TO 3 INCHES POSSIBLE TODAY.
TEMPERATURES WILL BE WARMER TODAY ACROSS LOWER ELEVATIONS...ESPECIALLY
IN WINDY AREAS AT THE BASE OF THE FOOTHILLS AND PALMER DIVIDE.
FURTHER NORTH AND EAST OF DENVER...COLD AIR MAY BE A BIT HARDER
TO SCOUR OUT.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 204 AM MST MON JAN 5 2015
NW FLOW ALOFT WILL REMAIN OVER THE AREA FM TUE INTO WED. SOME
MOISTURE WILL CONTINUE TO AFFECT THE NRN MTNS ON TUE HOWEVER LAPSE
RATES REMAIN STABLE SO ANY SNOW WILL BE VERY LIGHT. OVER NERN CO IT
WILL BE DRY ON TUE WITH A WEAK SFC LEE TROUGH ALONG THE FRONT RANGE.
ONCE AGAIN TEMP FCST WILL BE DEPENDENT ON LINGERING SNOW COVER.
GUIDANCE TEMPS WRM READINGS INTO THE LOWER TO MID 50S OVER DENVER
WITH 40S ACROSS THE PLAINS. HOWEVER 850-700 MB TEMPS WILL COOL
AROUND 3 DEGREES C AND WITH LESS DOWNSLOPE COMPONENT NOT SURE
READINGS ARE GOING TO BE AS WRM AS MONDAY SO WILL KEEP HIGHS IN THE
40S ALONG THE FRONT RANGE WITH 30S OVER THE FAR NERN PLAINS.
TUE NIGHT INTO WED ANOTHER SHOT OF COLD AIR WILL MOVE INTO NERN CO
WITH SHALLOW UPSLOPE THRU EARLY WED MORNING. LATEST CROSS-SECTIONS
SHOW ENOUGH MOISTURE FOR AT LEAST A SLIGHT CHC OF LIGHT SNOW OVER
NERN CO. IN THE MTNS WILL NOT MENTION ANY PCPN. AS FOR HIGHS
BELIEVE ECMWF HAS A BETTER HANDLE WITH COLD AIRMASS SO WILL KEEP
HIGHS IN THE TEENS OVER THE PLAINS WITH 25 TO 30 CLOSER TO THE
FOOTHILLS.
ON THU DRY WNW FLOW ALOFT WILL BE OVER THE AREA AS A SFC LEE TROUGH
REDEVELOPS OVER ERN CO. THIS SHOULD LEAD TO WARMER TEMPS WITH
READINGS RISING BACK INTO THE 45 TO 50 DEGREE RANGE AROUND DENVER
WITH UPPER 30S TO LOWER 40S OVER THE FAR NERN PLAINS. BY THU NIGHT
INTO A FRI ANOTHER SHOT OF COOLER AIR WILL MOVE INTO NERN CO. THUS
WILL DROP HIGHS BACK INTO THE 20S OVER THE PLAINS WITH LOWER TO MID
30S AROUND DENVER. BOTH THE ECMWF AND GFS SHOW SOME MOISTURE IN THE
LOWER LEVELS WITH SHALLOW UPSLOPE COMPONENT LATE THU NIGHT INTO FRI
MORNING SO IT WOULDN`T BE A TOTAL SURPRISE TO SEE AT LEAST A SLIGHT
CHC OF LIGHT SNOW OVER NERN CO. IN THE MTNS THERE IS SOME INCREASE
IN MOISTURE BY AFTN SO WILL MENTION A SLIGHT CHC OF SNOW AS WELL.
BY SAT THE ECMWF AND GFS CONTINUE TO DIFFER ON THE OVERALL PTRN.
THE ECMWF HAS DRY NWLY FLOW ALOFT OVER THE AREA WITH DOWNSLOPE
WARMING OCCURRING OVER NERN CO WHILE THE GFS SHOWS A WK
DISTURBANCE MOVING ACROSS WITH QUITE A BIT OF MOISTURE. IN
ADDITION THE GFS KEEPS A SHALLOW COLD AIRMASS OVER NERN CO AS
WELL. FOR NOW WILL KEEP A SLIGHT CHC OF PCPN IN THE FCST AND TREND
WITH THE COOLER GFS.
ON SUN THE GFS SHOWS ANOTHER WK DISTURBANCE MOVING ACROSS WITH
ANOTHER SHOT OF MOISTURE ESPECIALLY FOR THE MTNS WHILE KEEPING A
SHALLOW LYR OF COLD AIR OVER NERN CO. MEANWHILE THE ECMWF KEEPS
MAINLY DRY NWLY FLOW ALOFT OVER THE AREA HOWEVER IT DOES SHOW A
SHOT OF COOLER AIR MOVING INTO NERN CO DURING THE DAY.
&&
.AVIATION...(FOR THE TAFS THROUGH 00Z TUESDAY LATE AFTERNOON)
ISSUED AT 123 PM MST MON JAN 5 2015
THE GUSTY AND ERRATIC NATURE OF CHINOOK WINDS CREATING A FCST
CHALLENGE AT AIRPORT TERMINALS THIS AFTERNOON. SPEEDS AND
DIRECTIONS ALL OVER THE PLAINS. AT THIS HOUR WLY WINDS AT KDEN
GUSTING TO 30KTS AND AT KBJC NEAR THE FOOTHILLS 58KTS! WHILE AT
KAPA WINDS ARE VARIABLE AT 4 KTS. THAT/S CHINOOK WINDS FOR YOU.
WILL LIKELY CONTINUE TO CHASE WINDS FOR THE REMAINDER OF THE
AFTERNOON. OTHERWISE NO PRECIP AND VFR CONDITIONS NEXT 24 HOURS.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 5 PM MST THIS AFTERNOON FOR COZ037.
HIGH WIND WARNING UNTIL 11 PM MST THIS EVENING FOR COZ033>036.
&&
$$
UPDATE...BAKER
SHORT TERM...ENTREKIN
LONG TERM...RPK
AVIATION...BAKER
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
943 AM MST MON JAN 5 2015
.UPDATE...
ISSUED AT 943 AM MST MON JAN 5 2015
WINDS WILL CONTINUE TO HOWL IN THE HIGH COUNTRY AND ACROSS
NORTHERN PORTIONS OF SOUTH PARK FOR THE REMAINDER OF TODAY.
SEVERAL FRONT RANGE WIND SENSORS HAVE ALREADY MEASURED GUSTS IN
THE 70 TO 80 MPH RANGE. THE STRONGEST WIND GUST MEASURED THUS FAR
WAS 85 MPH AT THE GOLD HILL SITE JUST WEST OF BOULDER. THE 109 MPH
WIND GUST RECORDED DURING THE PAST SEVERAL HOURS AT THE KENOSHA
PASS WIND SENSOR IS IN ERROR. FOR SOME REASON THIS SENSOR LOCKS ON
109 MPH WHENEVER THERE`S STRONG WINDS...BLOWING SNOW AND/OR VERY
COLD TEMPERATURES AT THAT SITE.
THESE POTENTIALLY DAMAGING AND VERY GUSTY WEST WINDS ARE EXPECTED
TO BECOME MORE WIDESPREAD IN THE FRONT RANGE MOUNTAINS AND
FOOTHILLS BY LATE THIS MORNING WITH PEAK GUSTS TO AROUND 85 MPH
EXPECTED THROUGH LATE THIS AFTERNOON. THE STRONG WINDS ARE LIKELY
TO PRODUCE CONSIDERABLE BLOWING AND DRIFTING SNOW IN OPEN AREAS.
WINDS ARE EXPECTED TO DECREASE IN SPEED BY MID TO LATE THIS
EVENING. THAT SAID...WEST WINDS OF 25-40 AND GUSTS TO AROUND 60
MPH ACROSS NORTHERN PORTIONS OF SOUTH PARK HAS PROMPTED A BLOWING
SNOW ADVISORY FOR ZONE 37. ADVISORY GOES UNTIL 5 PM MST TODAY.
CDOT CAMS CLEARLY INDICATE QUITE A BIT OF BLOWING SNOW ALONG U.S.
HIGHWAY 285 NORTH OF FAIRPLAY.
ELSEWHERE...STRONG WESTERLY WINDS ARE JUST OFF THE SFC BASED ON
KFTG WIND PROFILER...ACARS WIND PLOTS AND LATEST RAP WIND DATA.
ANOTHER INDICATION OF THESE STRONG WINDS CAN BE SURMISED BY THE
RAPID RISE IN TEMPERATURE AT DIA IN THE PAST HOUR WHERE IT ROSE
FROM 17F TO 41F. SUSPECT ITS ONLY A MATTER OF TIME BEFORE GUSTY
WARM CHINOOK WINDS WILL MIX DOWN ACROSS PORTIONS OF THE I-25
URBAN CORRIDOR AND WRN PORTIONS OF THE PALMER DIVIDE. ITS ALREADY
IN THE LOW/MID 40S ON THE PALMER DVD IN DOUGLAS COUNTY.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT )
ISSUED AT 345 AM MST MON JAN 5 2015
MAIN CONCERN TODAY AND THIS EVENING IS THE HIGH WIND POTENTIAL IN
THE MOUNTAINS AND FOOTHILLS. CURRENT OBSERVATIONS SHOWING WINDS
BEGINNING TO INCREASE BUT STILL ONLY IN THE 30-45 MPH RANGE. 88D
ALSO SHOWING WIND SIGNATURE INCREASING IN THE PAST HOUR AS WINDS
BEGIN TO DESCEND THROUGH THE FOOTHILLS OF BOULDER COUNTY. SURFACE
PRESSURE ALSO BEGINNING TO FALL BUT BEST PRESSURE FALLS STILL
OVER MONTANA AND WYOMING. SURFACE PRESSURE GRADIENT WILL CONTINUE
TO STEEPEN ACROSS THE STATE AS THE ADDITIONAL FALLS WORK INTO
EASTERN COLORADO. LATEST MODELS SHOWING SURFACE GRADIENT TO
TIGHTEN TO AROUND 15 MB FROM GJT TO DEN BY LATER THIS AM AND
THROUGH THE AFTERNOON.
CROSS SECTIONS SHOWING 60-70KT CROSS BARRIER FLOW DEVELOPING THIS
MORNING BEFORE DECREASING THIS EVENING. STRONG MID LEVEL WARMING
WILL RESULT IN STRONG INVERSIONS DEVELOPING AT MOUNTAIN TOP LEVEL
ALONG WITH ADEQUATE WIND SHEAR PROFILE FOR AMPLIFIED MOUNTAIN
WAVE. THE ONE FACTOR AGAINST HIGH WINDS TODAY IS THE INCREASED
MOISTURE AND LIGHT SNOW EXPECTED OVER HIGHER NORTHERN MOUNTAINS.
LATEST RAP/HRRR SHOWING PEAK WIND GUSTS IN THE 60-80KT RANGE FROM
16Z-23Z. FEEL THERE ENOUGH CONFIDENCE TO UPGRADE THE WATCH TO A
WARNING FOR THE MOUNTAINS AND FOOTHILLS. WINDS MAY HAVE A HARD
TIME DEVELOPING ACROSS LOWER ELEVATIONS OF THE FOOTHILLS BUT
BELIEVE THE STRONG GRADIENT WILL AID IN THE WIND DEVELOPMENT.
EXPECT LIGHT SNOW TO DEVELOP OVER FAR NORTHERN MOUNTAINS TODAY BUT
EXPECT SNOWFALL AMOUNTS WILL BE ON THE LIGHT SIDE DUE TO LOW
LAPSE RATES DESPITE THE STRONG OROGRAPHIC FLOW. BEST SNOWFALL
LIKELY WILL BE OVER ZONE 31 WITH UP TO 3 INCHES POSSIBLE TODAY.
TEMPERATURES WILL BE WARMER TODAY ACROSS LOWER ELEVATIONS...ESPECIALLY
IN WINDY AREAS AT THE BASE OF THE FOOTHILLS AND PALMER DIVIDE.
FURTHER NORTH AND EAST OF DENVER...COLD AIR MAY BE A BIT HARDER
TO SCOUR OUT.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 204 AM MST MON JAN 5 2015
NW FLOW ALOFT WILL REMAIN OVER THE AREA FM TUE INTO WED. SOME
MOISTURE WILL CONTINUE TO AFFECT THE NRN MTNS ON TUE HOWEVER LAPSE
RATES REMAIN STABLE SO ANY SNOW WILL BE VERY LIGHT. OVER NERN CO IT
WILL BE DRY ON TUE WITH A WEAK SFC LEE TROUGH ALONG THE FRONT RANGE.
ONCE AGAIN TEMP FCST WILL BE DEPENDENT ON LINGERING SNOW COVER.
GUIDANCE TEMPS WRM READINGS INTO THE LOWER TO MID 50S OVER DENVER
WITH 40S ACROSS THE PLAINS. HOWEVER 850-700 MB TEMPS WILL COOL
AROUND 3 DEGREES C AND WITH LESS DOWNSLOPE COMPONENT NOT SURE
READINGS ARE GOING TO BE AS WRM AS MONDAY SO WILL KEEP HIGHS IN THE
40S ALONG THE FRONT RANGE WITH 30S OVER THE FAR NERN PLAINS.
TUE NIGHT INTO WED ANOTHER SHOT OF COLD AIR WILL MOVE INTO NERN CO
WITH SHALLOW UPSLOPE THRU EARLY WED MORNING. LATEST CROSS-SECTIONS
SHOW ENOUGH MOISTURE FOR AT LEAST A SLIGHT CHC OF LIGHT SNOW OVER
NERN CO. IN THE MTNS WILL NOT MENTION ANY PCPN. AS FOR HIGHS
BELIEVE ECMWF HAS A BETTER HANDLE WITH COLD AIRMASS SO WILL KEEP
HIGHS IN THE TEENS OVER THE PLAINS WITH 25 TO 30 CLOSER TO THE
FOOTHILLS.
ON THU DRY WNW FLOW ALOFT WILL BE OVER THE AREA AS A SFC LEE TROUGH
REDEVELOPS OVER ERN CO. THIS SHOULD LEAD TO WARMER TEMPS WITH
READINGS RISING BACK INTO THE 45 TO 50 DEGREE RANGE AROUND DENVER
WITH UPPER 30S TO LOWER 40S OVER THE FAR NERN PLAINS. BY THU NIGHT
INTO A FRI ANOTHER SHOT OF COOLER AIR WILL MOVE INTO NERN CO. THUS
WILL DROP HIGHS BACK INTO THE 20S OVER THE PLAINS WITH LOWER TO MID
30S AROUND DENVER. BOTH THE ECMWF AND GFS SHOW SOME MOISTURE IN THE
LOWER LEVELS WITH SHALLOW UPSLOPE COMPONENT LATE THU NIGHT INTO FRI
MORNING SO IT WOULDN`T BE A TOTAL SURPRISE TO SEE AT LEAST A SLIGHT
CHC OF LIGHT SNOW OVER NERN CO. IN THE MTNS THERE IS SOME INCREASE
IN MOISTURE BY AFTN SO WILL MENTION A SLIGHT CHC OF SNOW AS WELL.
BY SAT THE ECMWF AND GFS CONTINUE TO DIFFER ON THE OVERALL PTRN.
THE ECMWF HAS DRY NWLY FLOW ALOFT OVER THE AREA WITH DOWNSLOPE
WARMING OCCURRING OVER NERN CO WHILE THE GFS SHOWS A WK
DISTURBANCE MOVING ACROSS WITH QUITE A BIT OF MOISTURE. IN
ADDITION THE GFS KEEPS A SHALLOW COLD AIRMASS OVER NERN CO AS
WELL. FOR NOW WILL KEEP A SLIGHT CHC OF PCPN IN THE FCST AND TREND
WITH THE COOLER GFS.
ON SUN THE GFS SHOWS ANOTHER WK DISTURBANCE MOVING ACROSS WITH
ANOTHER SHOT OF MOISTURE ESPECIALLY FOR THE MTNS WHILE KEEPING A
SHALLOW LYR OF COLD AIR OVER NERN CO. MEANWHILE THE ECMWF KEEPS
MAINLY DRY NWLY FLOW ALOFT OVER THE AREA HOWEVER IT DOES SHOW A SHOT
OF COOLER AIR MOVING INTO NERN CO DURING THE DAY.
&&
.AVIATION...(FOR THE TAFS THROUGH 18Z TUESDAY MORNING)
ISSUED AT 943 AM MST MON JAN 5 2015
SOUTH-SOUTHWEST WINDS OF 6-12KTS AT KDEN AND KAPA ARE EXPECTED
TO TURN WESTERLY 15-25KTS IN THE NEXT HOUR...AND AFTER THAT
POSSIBLY GUST TO AROUND 35KTS. STRONGER WEST WINDS ARE LIKELY
CLOSER TO THE FTHLS SUCH AS AT KBJC WHERE GUSTS TO AROUND 45 KTS
WILL BE POSSIBLE DURING THE LATE MORNING AND AFTERNOON HOURS.
BLOWING SNOW MAY BRIEFLY REDUCE VISIBILITIES AT THESE LOCATIONS
ESPECIALLY AT KBJC. WINDS ARE EXPECTED TO SUBSIDE AT KDEN AND KAPA
EARLY THIS EVENING AND TURN DRAINAGE...AND BY MID TO LATE EVENING
AT KBJC.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 5 PM MST THIS AFTERNOON FOR COZ037.
HIGH WIND WARNING UNTIL 11 PM MST THIS EVENING FOR COZ033>036.
&&
$$
UPDATE...BAKER
SHORT TERM...ENTREKIN
LONG TERM...RPK
AVIATION...BAKER
AREA FORECAST DISCUSSION
NWS TAUNTON MA
1015 PM EST TUE JAN 6 2015
.SYNOPSIS...
AN ARCTIC FRONT SWEEPS SOUTHERN NEW ENGLAND WEDNESDAY BRINGING
WITH IT A CHANCE OF SNOW-SQUALLS WHILE BEHIND IT BLUSTERY AND
BITTERLY COLD CONDITIONS FOLLOW INTO THURSDAY. A BRIEF PERIOD OF
LIGHT SNOW IS LIKELY VERY LATE THURSDAY NIGHT INTO FRIDAY MORNING
AS TEMPERATURES MODERATE AHEAD OF ANOTHER COLD FRONT.
THERE IS ALSO A CONCERN FOR STRONG TO PERHAPS EVEN
DAMAGING WIND GUSTS ON FRIDAY ACROSS THE SOUTHEAST NEW
ENGLAND COAST. OTHERWISE...MAINLY COLD AND DRY WEATHER
EXPECT THIS WEEKEND INTO EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
1015 PM UPDATE...
MADE SOME CHANGES TO THE OVERNIGHT FORECAST BASED ON LATEST
OBSERVATIONS. 3.9 MICRON SATELLITE IMAGERY...AND SURFACE
OBSERVATIONS...SHOWING MORE THAN A FEW BREAKS IN THE CLOUDS ACROSS
INTERIOR SOUTHERN NEW ENGLAND. AS A RESULT...HAD TO KNOCK
TEMPERATURES DOWN A FEW DEGREES. 07/01Z HRRR APPEARS TO HAVE A
GOOD HANDLE ON THINGS TEMPERATURE-WISE FOR THE REST OF TONIGHT.
INITIAL DIP...FOLLOWED BY A BRIEF RISE AS SOME CLOUDS MOVE
OVERHEAD...WITH A FINAL DIP JUST BEFORE SUNRISE.
PRETTY DRY OVERNIGHT AWAY FROM THE IMMEDIATE SOUTH COAST. SHOULD
NOT BE MUCH MORE THAN FLURRIES...WITH AN ADDITIONAL DUSTING AT
MOST FOR ACCUMULATION.
PREVIOUS DISCUSSION...
BECOMING SITUATED BENEATH HIGH PRESSURE NESTLED BETWEEN THE CLIPPER
LOW MOVING OUT TO SEA AND THE APPROACHING MID-LEVEL DISTURBANCE
ACROSS THE N GREAT LAKES REGION. THIS PERHAPS MAY ALLOW A PERIOD OF
CLEARING CONDITIONS UNDER LIGHT W/SW-WINDS...A POSSIBLE RADIATIONAL
COOLING SETUP ACROSS THE INTERIOR. BUT NOT ENTIRELY CONFIDENT ON THE
CLOUD COVER.
NEVERTHELESS...IT IS GOING TO BE COLD TONIGHT. LOWS DOWN INTO THE
SINGLE DIGITS AND TEENS N TO S. FEELING COLDER ALONG THE SHORES AS
BREEZY WINDS PERSIST ADJACENT TO THE WARMER OCEAN. DESPITE LOWS INTO
THE TEENS...WILL FEEL LIKE THE SINGLE DIGITS.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/...
*** BITTERLY COLD CONDITIONS ANTICIPATED LATE WEDNESDAY ON THROUGH
THURSDAY MORNING WITH WIND CHILL VALUES FALLING AS LOW AS 30
BELOW ZERO FOR THURSDAY MORNING ***
WEDNESDAY...
ARCTIC COLD FRONT SWEEPING ACROSS THE REGION DRIVING MUCH COLDER AIR
SOUTHWARD. H85 TEMPERATURES DROPPING TO -20C ALLOWING LAPSE RATES TO
STEEPEN TOWARDS DRY-ADIABATIC ALLOWING THE MIX-DOWN OF FASTER WINDS
ALOFT TO THE SURFACE. ANTICIPATING WINDS TO BACK NW WHILE INCREASING
TO VALUES OF 15 TO 20 MPH SUSTAINED...25 TO 35 MPH GUSTS. WINDS WILL
BE MUCH STRONGER ALONG THE SHORES ADJACENT TO THE WARMER OCEAN WITH
GUSTS UP TO 45 MPH.
SOME CONCERNS TO THE OVERALL FORECAST...
FIRST: THE PRESENCE OF SNOW SQUALLS PARENT WITH THE SWEEPING ARCTIC
COLD FRONT. STEEP LOW-LEVEL LAPSE RATES COINCIDING WITH SOME MOISTURE
IN THE LOW-LEVELS. THERE IS THE POSSIBILITY...THEN AGAIN IT COULD
BE A BIG BUST. NEVERTHELESS MAIN AREA OF CONCERN IS ON THE W-SLOPES
OF HIGHER TERRAIN WHERE OROGRAPHIC TENDENCIES COULD AID IN THE
LIFT OF ANY AVAILABLE MOISTURE IN A MOSTLY UNSTABLE ENVIRONMENT.
WITH ANY SNOW-SQUALL ACTIVITY...WOULD EXPECT NEAR WHITE-OUT
CONDITIONS WITH A QUICK INCH OR TWO OF SNOW...DEPENDING ON THE
PERSISTENCE OF THE SNOW-SQUALL. HAZARDOUS TRAVEL CONDITIONS WITHIN
ANY WHITE-OUT CONDITIONS THAT MOTORISTS SHOULD BE AWARE AND
PREPARED FOR...ESPECIALLY AS ROAD CONDITIONS WILL CHANGE.
SECOND: OCEAN-EFFECT SNOWS ACROSS THE E-HALF OF THE CAPE. WITH THE
NW-FLOW...FAVORABILITY IS OVER THE E-CAPE. CYCLONIC FLOW AT H85...UNIFORM
WINDS UP TO H8...DECENT MOISTURE AVAILABLE...AND A STRONG
TEMPERATURE DIFFERENCE FROM A +5-6C OCEAN TEMPERATURE TO AROUND
-20C AT H85 NETTING OVER A 20-DEGREE DIFFERENCE. PER BUFKIT
PROFILES...CAPE VALUES AROUND 1000 J/KG WITH NCAPE VALUES AROUND
0.25 INDICATE AN UNSTABLE OCEAN-INDUCED ENVIRONMENT. SOMETHING
THAT WE WILL NEED TO WATCH. RIGHT NOW THE FORECAST CALLS FOR
ROUGHLY 1-2 INCHES AND AM COMFORTABLE WITH THIS FORECAST WITH THE
LESS N-TRAJECTORY OF THE FLOW AND LESS FETCH ACROSS THE WATERS.
BUT WILL NEED TO MONITOR AS TO WHETHER ADVISORIES WILL BE NEEDED
SHOULD AMOUNTS BE FORECASTED HIGHER.
WEDNESDAY NIGHT...
JUST DARN COLD. BEHIND THE ARCTIC FRONT ANTICIPATE NW-WINDS 15 TO 20
MPH WITH GUSTS AROUND 35 MPH DRIVING TEMPERATURES DOWN TOWARDS LOWS
WELL BELOW ZERO FOR MOST LOCATIONS BY THURSDAY MORNING. STRONGEST
WINDS WILL BE ACROSS THE HIGHER TERRAIN AND ALONG THE SHORES WITH
GUSTS UP TO 40 MPH. HEIGHT OF THE WINDS WILL BE DURING THE EVENING
TAPERING OFF TOWARDS MORNING AS HIGH PRESSURE BUILDS FROM THE W.
WINDS PARENT WITH THE ARCTIC AIRMASS ARE FORECAST TO YIELD AVERAGE
WIND CHILL VALUES BETWEEN -15 TO -25 DEGREES ACROSS MUCH OF S NEW
ENGLAND...-25 TO -35 ACROSS THE E-SLOPES OF THE BERKSHIRES AND
ACROSS THE WORCESTER HILLS. WITH A PERSISTENT SIGNAL OVER THE LAST
SEVERAL DAYS...HAVE DROPPED THE WIND CHILL WATCH AND CONVERTED IT
OVER TO A COMBINATION OF WIND CHILL ADVISORIES AND WIND CHILL
WARNINGS. ONLY THE ISLANDS PRESENTLY ARE SPARED FROM WIND CHILL
HEADLINES...WITH FORECAST WIND CHILL VALUES AROUND -5 TO -15 DEGREES.
WILL STILL BE CONTENDING WITH OCEAN-INDUCED STRATUS AND SNOW ACROSS
THE E-CAPE...SOME OF THAT ACTIVITY DRIFTING DOWN INTO NANTUCKET. AS
MENTIONED EARLIER...THE STORM-TOTAL SNOWFALL FORECAST CALLS FOR 1-2
INCHES AND FEEL COMFORTABLE WITH THIS FORECAST WITH THE DRIER ARCTIC
AIRMASS LIMITING MOISTURE AVAILABILITY AND LESS N-FETCH OF THE WINDS
OVER THE WATERS TOWARDS THE E-CAPE.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
HIGHLIGHTS...
* WIND CHILLS THURSDAY MORNING OF 15 TO 30 BELOW ZERO
* A DUSTING TO 1 INCH OF SNOW LIKELY FRIDAY
* STRONG TO EVEN DAMAGING WINDS FRIDAY FOR SE NEW ENGLAND COAST
* MAINLY DRY AND COLD THIS WEEKEND
* NEED TO WATCH A STORM EARLY NEXT WEEK - BUT PROB STAYS SOUTH OF US
OVERVIEW...
UPPER LEVEL BLOCKING INTO ALASKA WILL CONTINUE THROUGH THE WEEKEND.
THIS WILL FORCE THE POLAR JET SOUTH RESULTING IN BELOW NORMAL TEMPS
THROUGH THE WEEKEND...BUT NOT NEARLY AS COLD AS WHAT WE WILL BE
DEALING WITH WED NIGHT/THU MORNING. THE RIDGING DOES WEAKEN A BIT
EARLY NEXT WEEK AND WE GET INTO MORE OF A WEST SOUTHWEST FLOW OF
AIR ALOFT. HOWEVER...A PRETTY STRONG SURFACE HIGH SETS UP ACROSS
EASTERN CANADA...SO TEMPS WILL PROBABLY STILL BE BELOW NORMAL. WE
WILL HAVE TO WATCH A STORM EARLY NEXT WEEK TO OUR SOUTH. ODDS ARE
THAT IS STAYS SOUTH OF US OR JUST GIVES A GLANCING BLOW...GIVEN
LITTLE DOWNSTREAM BLOCKING. NONETHELESS...ITS A WEEK OUT SO
NOTHING IS SET IN STONE.
THURSDAY...
DANGEROUS AND BITTERLY COLD WIND CHILLS BETWEEN 15 AND 30 BELOW ZERO
WILL CONTINUE INTO MID MORNING. THERE WILL BE SOME RELIEF BY
AFTERNOON AS 850T RISE TO NEAR -16C...BUT IT STILL WILL BE VERY
COLD AND WELL BELOW NORMAL. AFTERNOON HIGHS SHOULD RECOVER INTO
THE UPPER TEENS TO AROUND 20 FOR MOST LOCATIONS UNDER PARTLY TO
MOSTLY SUNNY SKIES.
THURSDAY NIGHT AND FRIDAY...
APPROACHING SHORTWAVE THU NIGHT WILL INDUCE A STRONG SOUTHWEST LOW
LEVEL JET. TEMPS MAY BRIEFLY DROP A BIT IN TYPICALLY SHELTERED
AREAS ACROSS THE INTERIOR JUST AFTER SUNSET. OTHERWISE...TEMPS
WILL RISE FOR MOST LOCATIONS AS SOUTHWEST WINDS ALLOW MILDER AIR
TO MIX DOWN. IN FACT...TEMPS SHOULD REALLY JUMP ACROSS THE
CAPE/ISLANDS WITH STRONG SOUTHWEST WINDS BLOWING OFF THE OCEAN. BY
DAYBREAK FRI...TEMPS SHOULD BE IN THE UPPER 30S TO THE LOWER 40S
ACROSS CAPE/ISLANDS!
THIS SHORTWAVE WILL BE FAST MOVING...BUT WILL BRING A BRIEF ROUND OF
LIGHT SNOW SHOWERS TO MOST OF THE REGION VERY LATE THU NIGHT INTO
FRI MORNING. MAINLY JUST EXPECTING A DUSTING TO 1 INCH OF SNOW AS
SHORTWAVE WILL BE FAST MOVING AND NOT BE ABLE TO TAP A LOT OF
MOISTURE. LOW PROBABILITY THAT A FEW LOCATIONS RECEIVE UP TO 2
INCHES OF SNOW. RAPIDLY WARMING BOUNDARY LAYER MAY ALLOW FOR EVEN
SOME RAIN SHOWERS TO MIX IN ACROSS CAPE/ISLANDS. BEFORE THAT
HAPPENS THOUGH...MAY SEE SOME OCEAN EFFECT SNOW SHOWERS FROM THE
SOUTHWEST GIVEN VERY ANTECEDENT COLD AIRMASS IN PLACE.
THE OTHER CONCERN FOR FRIDAY WILL BE STRONG TO PERHAPS EVEN DAMAGING
WINDS ALONG THE SOUTHEAST NEW ENGLAND COAST. 60 KNOT SOUTHWEST
LOW LEVEL JET DEVELOPS IN THE WARM AIR ADVECTION PATTERN. NORMALLY
MUCH OF THIS DOES NOT MIX DOWN BECAUSE OF THE INVERSION. HOWEVER
SINCE ITS QUITE COLD ALOFT AND THE OCEAN IS STILL RELATIVELY
MILD...THIS CASE IS A BIT DIFFERENT. FEEL THAT A WIND ADVISORY
WILL LIKELY BE NEEDED FOR THE SOUTHEAST NEW ENGLAND COAST...WITH
PERHAPS EVEN HIGH WIND CRITERIA BEING MET ACROSS NANTUCKET AND
PORTIONS OF THE CAPE. STILL TOO EARLY FOR ANY HEADLINES...BUT
SOMETHING LATER SHIFTS WILL HAVE TO WATCH CLOSELY.
SATURDAY THROUGH TUESDAY...
UPPER LEVEL FLOW GRADUALLY BECOMES MORE WEST SOUTHWEST BY EARLY NEXT
WEEK. HOWEVER...STRONG HIGH PRESSURE ACROSS EASTERN CANADA WILL
PROBABLY KEEP OUR TEMPS BELOW NORMAL. DRY WEATHER LOOKS TO
DOMINATE OVER THIS TIME...BUT WILL HAVE TO WATCH A STORM TO OUR
SOUTH MONDAY NIGHT INTO TUESDAY. ODDS FAVOR IT STAYS SOUTH OR JUST
GRAZES US GIVEN UPPER LEVEL PATTERN...BUT CAN/T RULE OUT A FURTHER
NORTH TRACK.
&&
.AVIATION /03Z WEDNESDAY THROUGH SUNDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH TUESDAY/...
03Z UPDATE...
TONIGHT...EXPECTING MAINLY VFR CONDITIONS OVERNIGHT WITH RATHER
LIGHT WINDS. PATCHY MVFR TOWARD THE SOUTH COAST IN HEAVIER SNOW
SHOWERS.
WEDNESDAY...ARCTIC FRONT PUSHES ACROSS THE TERMINALS. TEMPO MVFR-
IFR POSSIBLE WITH SNOW ALONG THE FRONT. WINDS BACKING NW
INCREASING WITH GUSTS 30-40 KT TOWARDS THE LATE-HALF OF THE DAY.
STRONGEST WINDS ALONG THE HIGH TERRAIN AND NEAR-SHORES.
WEDNESDAY NIGHT...NW-WINDS CONTINUE. STRONGEST ALONG HIGH TERRAIN
AND NEAR-SHORES. VFR EXCEPT IN VICINITY OF THE CAPE WHERE OCEAN-
EFFECT STRATUS / SNOW COULD RESULT IN MVFR-IFR MIX. HIGHEST
CONFIDENCE ACROSS THE E-CAPE.
KBOS TERMINAL...MODERATE CONFIDENCE IN TAF.
KBDL TERMINAL...MODERATE CONFIDENCE IN TAF.
OUTLOOK...THURSDAY INTO SUNDAY...
THURSDAY...HIGH CONFIDENCE IN MAINLY VFR.
THURSDAY NIGHT AND FRIDAY...MODERATE CONFIDENCE. A PERIOD MVFR
CONDITIONS IN LIGHT SNOW SHOWERS LIKELY VERY LATE THU NIGHT INTO FRI
MORNING. EXPECT A SOUTHWEST LOW LEVEL JET OF 60 KNOTS TO GENERATE
LOW LEVEL WIND SHEAR. IN ADDITION...SOUTHWEST WIND GUSTS OF 40 TO
50 KNOTS ARE EXPECTED VERY LATE THU NIGHT/FRI ALONG THE SOUTHEAST
NEW ENGLAND COAST. STRONGEST WINDS EXPECTED ACROSS NANTUCKET.
SATURDAY AND SUNDAY...HIGH CONFIDENCE IN MAINLY VFR CONDITIONS.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH TUESDAY/...HIGH CONFIDENCE.
1015 PM UPDATE...
TONIGHT...
LIGHT SNOW SHOWERS/FLURRIES WIND DOWN BY LATE EVENING.
OTHERWISE...WINDS/SEAS REMAIN BELOW SCA THRESHOLDS WITH RELATIVELY
WEAK PRESSURE GRADIENT.
WEDNESDAY INTO WEDNESDAY NIGHT...HIGH CONFIDENCE.
ARCTIC FRONT SWEEPS ACROSS THE WATERS LATE BEHIND AHEAD OF WHICH
INCREASING W-WINDS TO GALE FORCE BACK OUT OF THE NW WITH PASSAGE
AND GUST IN EXCESS OF 40 KTS ON THE OUTER WATERS. SEAS BUILDING
10 TO 14 FEET ALONG WITH THE LIKELIHOOD OF MODERATE FREEZING SPRAY
AS OCEAN TEMPERATURES AVERAGE AROUND 42 DEGREES IN CONDITIONS OF
CHOPPY SEAS AND STRONG WINDS.
GALE WARNINGS AND FREEZING SPRAY ADVISORIES ISSUED ACCORDINGLY
BEGINNING AROUND MIDDAY WEDNESDAY AND CONTINUING INTO THURSDAY
MORNING.
OUTLOOK...THURSDAY THROUGH SUNDAY...MODERATE TO HIGH CONFIDENCE.
THURSDAY...MODERATE FREEZING SPRAY AND NORTHWEST WIND GUSTS OF 25 TO
30 KNOTS EXPECTED IN STRONG COLD ADVECTION DURING THE MORNING.
WINDS MAY SLACKEN A BIT IN THE AFTERNOON...BUT GIVEN ITS STILL SO
COLD ALOFT EXPECT SCA WIND GUSTS TO CONTINUE.
THURSDAY NIGHT AND FRIDAY...STRONG SOUTHWEST LOW LEVEL JET DEVELOPS
AHEAD OF NEXT SHORTWAVE. NORMALLY MUCH OF THESE WINDS DO NOT MIX
DOWN...BUT SINCE ITS SO COLD ALOFT AND OCEAN IS RELATIVELY MILD
THIS IS A BIT OF A DIFFERENT CASE. HIGH CONFIDENCE IN GALE
WARNINGS FOR MOST WATERS LATE THU NIGHT INTO FRI. IN FACT...A
DECENT SHOT AT STORM FORCE WIND GUSTS ACROSS OUR SOUTHERN WATERS
WITH THE POTENTIAL FOR 50 KNOT WIND GUSTS.
SATURDAY AND SUNDAY...STILL POTENTIAL FOR PERIODS OF SMALL CRAFT
ADVISORY WIND GUSTS GIVEN DECENT WINDS OFF THE GROUND AND RELATIVELY
COLD TEMPERATURES ALOFT. WIND DIRECTION WILL BE MAINLY FROM THE
WEST.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...WIND CHILL ADVISORY FROM 5 PM WEDNESDAY TO 10 AM EST THURSDAY
FOR CTZ002>004.
MA...WIND CHILL ADVISORY FROM 5 PM WEDNESDAY TO 10 AM EST THURSDAY
FOR MAZ005>007-010>022-026.
WIND CHILL WARNING FROM 5 PM WEDNESDAY TO 10 AM EST THURSDAY
FOR MAZ002>004-008-009.
RI...WIND CHILL ADVISORY FROM 5 PM WEDNESDAY TO 10 AM EST THURSDAY
FOR RIZ001>007.
MARINE...FREEZING SPRAY ADVISORY FROM 6 PM WEDNESDAY TO 8 AM EST
THURSDAY FOR ANZ231>235-237-250-251-254>256.
GALE WARNING FROM 1 PM WEDNESDAY TO 10 AM EST THURSDAY FOR
ANZ232>235-237.
GALE WARNING FROM 4 PM WEDNESDAY TO 5 AM EST THURSDAY FOR
ANZ230.
GALE WARNING FROM 4 PM WEDNESDAY TO 8 AM EST THURSDAY FOR
ANZ231-251.
GALE WARNING FROM 1 PM WEDNESDAY TO 8 AM EST THURSDAY FOR
ANZ236-250.
GALE WARNING FROM 10 AM WEDNESDAY TO 10 AM EST THURSDAY FOR
ANZ254>256.
&&
$$
SYNOPSIS...FRANK/SIPPRELL
NEAR TERM...BELK/FRANK/SIPPRELL
SHORT TERM...SIPPRELL
LONG TERM...FRANK
AVIATION...BELK/FRANK/SIPPRELL
MARINE...BELK/FRANK/SIPPRELL
AREA FORECAST DISCUSSION
NWS TAUNTON MA
127 PM EST MON JAN 5 2015
.SYNOPSIS...
INTENSIFYING LOW PRESSURE HEADING INTO THE MARITIMES TODAY WILL
YIELD BLUSTERY AND MUCH COLDER WEATHER FOR SOUTHERN NEW ENGLAND
ALONG WITH THE RISK OF A FEW SNOW SHOWERS/SQUALLS POSSIBLE. WEAK
LOW PRESSURE MAY BRING A PERIOD OF LIGHT SNOW DURING TUESDAY. AN
ARCTIC FRONT CROSSES THE REGION WEDNESDAY...WHICH MAY PRODUCE A
FEW SNOW SHOWERS OR SQUALLS. BLUSTERY AND BITTERLY COLD CONDITIONS
ARE EXPECTED WEDNESDAY NIGHT INTO THURSDAY. MORE SNOW SHOWERS ARE
POSSIBLE THURSDAY NIGHT AND FRIDAY...THEN MAINLY DRY CONDITIONS
INTO NEXT WEEKEND WITH BELOW NORMAL TEMPERATURES.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
115 PM UPDATE...
WIND GUSTS OF 30 TO IN SOME LOCALES 40+ KNOTS HAVE OCCURRED IN
SOUTHERN NEW ENGLAND TODAY...WITH THE HIGHEST GUSTS OVER PORTIONS
OF EASTERN MA INCLUDING BOSTON...AS WELL AS THE WORCESTER HILLS.
ALSO THERE HAVE BEEN REPORTS OF TREES DOWN /SEE LATEST LSRBOX/.
WIND GUSTS AT CT VALLEY AREA METAR SITES HAVE BEEN SOMEWHAT LOWER
THAN TO THE EAST...BUT NAM AND HRRR BUFKIT FORECAST SOUNDINGS
SHOWING POTENTIAL FOR 40 KTS TO MIX TO THE GROUND. CONTINUING THE
WIND ADVISORY FOR THE COUNTY WARNING AREA.
CONTINUE TO SEE CLOUD BANDS CROSSING NEW YORK STATE AND EXTENDING
INTO OUR AREA...WITH ISOLATED SNOW SHOWERS ON RADAR. WILL CONTINUE
TO MENTION POTENTIAL FOR ISOLATED/WIDELY SCATTERED SNOW SHOWERS.
THERE IS STILL A POSSIBILITY FOR AN ISOLATED SNOW SQUALL THIS
AFTERNOON. TEMPS/DEWPTS CONTINUE TO FALL AS COLDER AIR POURS IN.
MINOR ADJUSTMENTS TO TEMPS/SKY COVER THIS AFTERNOON...OTHERWISE
FORECAST LOOKS ON TRACK.
PREVIOUS DISCUSSION...
WINDS...
POST FRONTAL AIRMASS STREAMING ACROSS THE REGION EARLY THIS
MORNING WITH WITH WEST WINDS GUSTING ALREADY UP TO 40 MPH. AS COLD
AIR ADVECTION INCREASES ALONG WITH THE PRES GRADIENT AND DEEPENING
BLYR WILL RESULT IN WIND GUSTS VERY CLOSE TO WIND ADVISORY
CRITERIA /SUSTAINED 31 MPH AND GREATER AND-OR G46MPH AND HIGHER/.
DOWNSLOPE WIND COMPONENT /WNW WINDS/ WILL PROVIDE SOME ENHANCEMENT
AS WELL. THUS WIND ADVISORY FOR ALL AREAS TODAY.
SNOW SQUALL POTENTIAL...
OTHER CONCERN FOR TODAY IS POTENTIAL FOR LAKE EFFECT SNOW
SHOWERS/SQUALLS FROM NY STATE TO TRAVERSE INTO MA/RI AND CT. ALL
MODEL GUIDANCE ESPECIALLY THE HI RES MODELS SHOW LONG FETCH ACROSS
LAKE ONTARIO WITH STREAMLINES INDICATING A NARROW BAND OF
CONVERGENCE INTO SOUTHERN NEW ENGLAND TODAY. FAIRLY STEEP LOW
LEVEL LAPSE RATES TO ENHANCE POTENTIAL BAND DEVELOPMENT AND
DURATION. THE 00Z BTV 4KM WRF IS CURRENT SIMULATING THE LAKE
EFFECT BANDS VERY WELL ACROSS NY STATE EARLY THIS MORNING. THIS
MODEL TRAVERSE THESE STREAMERS ACROSS THE NH/MA BORDER LATER THIS
MORNING AND THEN INTO MA EARLY THIS AFTERNOON AND POSSIBLY
PROPAGATING INTO CT/RI AND SOUTHEAST MA LATE THIS AFTERNOON TOWARD
SUNSET. THESE MESOSCALE BANDS ARE ALWAYS DIFFICULT TO FORECAST
ESPECIALLY SO FAR DOWNSTREAM FROM THE LAKES. THUS WE HAVE ABOVE
AVERAGE FORECAST CONFIDENCE THAT ONE OR MORE OF THESE BANDS WILL
SURVIVE SOMEWHERE INTO MA/CT AND-OR RI BUT LOW CONFIDENCE ON AREAL
COVERAGE/INTENSITY AND DURATION. WHILE THESE SNOW BANDS TYPICALLY
DON`T DELIVER HEAVY SNOW AMOUNTS...ANY SNOW BAND TODAY WILL HAVE
THE POTENTIAL TO DUMP A QUICK HALF INCH OF SNOW IN A VERY SHORT
PERIOD OF TIME ALONG WITH REDUCED VSBY AND BRIEF SLICK CONDITIONS.
WILL ISSUE A SPECIAL WEATHER STATEMENT TO INCREASE PUBLIC
AWARENESS REGARDING THE UNCERTAINTY BUT ALSO THE POTENTIAL BRIEF
BUT HIGH IMPACT.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
TONIGHT...
ANY EARLY EVENING SNOW SHOWER ACTIVITY WILL WEAKEN/ERODE OR MOVE
OFF THE SOUTH COAST SHORTLY AFTER SUNSET. COLD NIGHT AHEAD IN THE
WAKE OF THE SHORT WAVE PASSAGE FROM TODAY. HIGH PRES OVER OH VLY
WILL CREST OVER NEW ENGLAND. THIS WILL SET THE STAGE FOR IDEAL
RADIATIONAL COOLING CONDITIONS WITH ALL LOCATIONS FALLING INTO THE
TEENS WITH SINGLE DIGITS WELL INLAND.
TUESDAY...
CLIPPER-TYPE LOW RACES ACROSS THE REGION AND WILL BE ACCOMPANIED
BY A PERIOD OF LIGHT SNOW REGIONWIDE. FAIRLY LOW AMPLITUDE SHORT
WAVE ALONG WITH MOISTURE LACKING AND SYSTEM IS VERY PROGRESSIVE.
THUS ALL MODEL GUID ONLY OFFERS A FEW HUNDREDS OF QPF. THEREFORE
AS OF NOW JUST EXPECTING A COATING TO PERHAPS AN INCH OF SNOW.
HOWEVER WILL HAVE TO WATCH LATER MODEL RUNS AND SEE IF
AMPLITUDE AND MOISTURE SIMULATIONS CHANGE.
IT WILL BE A COLD DAY GIVEN THE CHILLY START FOLLOWED BY CLOUDS
RAPIDLY INCREASING ALONG WITH LIGHT SNOW/FLURRIES BY AFTERNOON.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
HIGHLIGHTS...
* LEFTOVER LIGHT SNOW WILL PUSH OFFSHORE TUE NIGHT BUT MAY LINGER
ACROSS CAPE COD AND THE ISLANDS
* SCT SNOW SHOWERS AND A FEW SQUALLS POSSIBLE WED AS ARCTIC FRONT
PASSES
* DANGEROUSLY LOW WIND CHILL READINGS WED NIGHT INTO THU MORNING
* MODERATION IN TEMPS INTO THE WEEKEND BUT REMAINING BELOW NORMAL
OVERVIEW...
HEMISPHERIC TELECONNECTION INDICES CONTINUE TO SHOW GENERALLY
PROGRESSIVE PATTERN ACROSS THE LOWER 48 THROUGH THIS TIMEFRAME.
HOWEVER...-EPO PATTERN LOOKS TO CONTINUE A STRONG E PACIFIC RIDGE
WITH DEEP TROUGH ACROSS THE EASTERN U.S. AND CANADA THROUGH MID
WEEK...THEN WILL SLOWLY PROGRESS E.
WITH WEAK SHORT WAVES IN THE UPPER W-NW FLOW THAT BECOMES MORE NW
BY LATE THIS WEEK...EXPECT TO SEE PERIODS OF SNOW SHOWERS MOVE
ACROSS THE REGION BRINGING PROGRESSIVELY FRIGID AIR. THERE MAY BE
A FEW SNOW SQUALLS DURING WED AS AN ARCTIC FRONT PASSES...BRINGING
THE MOST BRUTALLY COLD CONDITIONS OF THE SEASON. WILL SEE TEMPS
PLUMMET ALONG WITH STRONG NW WINDS CAUSING DANGEROUSLY LOW WIND
CHILL READINGS. VERY STRONG HIGH WILL PASS S OF NEW ENGLAND
THU...THEN ANOTHER SHORT WAVE WILL PUSH THROUGH LATE THIS WEEK
WITH ANOTHER ROUND OF SNOW SHOWERS. SOME QUESTION HOW THIS HIGH
WILL SET UP NEAR OR N OF THE REGION NEXT WEEKEND. KEPT DRY
CONDITIONS FOR NOW ALONG WITH SOME MODERATION OF TEMPERATURES
THOUGH REMAINING BELOW SEASONAL NORMALS.
TUESDAY NIGHT...
FAST MOVING CLIPPER LOW WILL PUSH OFFSHORE...TAKING ITS LIGHT
SNOW WITH IT. THE LOW DOES LOOK TO DEEPEN WHILE MOVING E...BUT
SOME QUESTION AS TO WHETHER THIS MAY ENHANCE THE SNOWFALL SOMEWHAT
ACROSS OUTER CAPE COD AND NANTUCKET. OTHERWISE...EXPECT CONDITIONS
TO IMPROVE OVERNIGHT THOUGH TEMPS DROP OFF TO THE TEENS AT MOST
LOCATIONS...EXCEPT THE LOWER-MID 20S ALONG THE IMMEDIATE COAST.
WEDNESDAY...
ARCTIC FRONT WILL HEAD SE ACROSS THE REGION DURING THE AFTERNOON
AS OVERALL H5 BROAD TROUGH BEGINS TO AMPLIFY. MODELS CONTINUE TO
SIGNAL POTENTIAL FOR SCT SNOW SHOWERS AND POSSIBLY A FEW LOCALLY
HEAVY SNOW SQUALLS AS THE FRONT MOVES ACROSS WITH PRETTY GOOD
LOW LEVEL MOISTURE IN PLACE ALONG WITH H5 SHORT WAVE IN THE
DIGGING UPPER FLOW. EXPECT EXCELLENT LOW LEVEL MIXING TO DEVELOP
AS ARCTIC AIR BEGINS TO FILTER IN LATE IN THE DAY. W-NW WIND GUSTS
TO 30-40 MPH AND TEMPS FALLING INTO THE TEENS AWAY FROM THE COAST
BY EVENING.
WEDNESDAY NIGHT AND THURSDAY...
CORE OF COLDEST AIR WILL DIVE INTO NEW ENGLAND WED NIGHT. VERY
STRONG CAA AS H85 TEMPS DROP TO -25C TO -30C OVERNIGHT. EXCELLENT
LOW LEVEL MIXING AND DECENT PRES GRADIENT WILL COMBINE TO KEEP
NW WIND GUSTS ON ORDER OF 30-40 MPH...POSSIBLY HIGHER ACROSS CAPE
COD AND THE ISLANDS. WITH THIS ARCTIC AIRMASS ALONG WITH SOME SNOW
COVER IN PLACE...EXPECT TEMPS TO DROP BELOW ZERO ACROSS MOST
INTERIOR AREAS AND MAY EVEN FLIRT WITH ZERO IN THE BOSTON AND
PROVIDENCE METRO AREAS. DANGEROUSLY LOW WIND CHILLS EXPECTED...AS
LOW AS -20 TO -30 OVERNIGHT INTO THU MORNING. WIND CHILL HEADLINES
WILL LIKELY BE NEEDED FOR MOST AREAS. MAY ALSO SEE OCEAN EFFECT
SNOW SHOWERS LINGERING ACROSS THE OUTER CAPE AND NANTUCKET.
CORE OF COLD AIR MOVES OFFSHORE DURING THU WITH TEMPS RISING TO
THE TEENS /STILL RUNNING 15 TO 20 DEGREES BELOW SEASONAL NORMS/.
THURSDAY NIGHT AND FRIDAY...
ANOTHER FAST MOVING SHORTWAVE APPROACHES...WHICH MAY BRING ANOTHER
ROUND OF SNOW SHOWERS. WITH THE COLD AIR IN PLACE AND WINDS
SHIFTING TO SW...MIGHT SEE SOME S COASTAL OCEAN EFFECT SNOW
SHOWERS DEVELOP LATE THU NIGHT INTO FRI BEFORE NEXT SYSTEM MOVES
ACROSS. WILL ALSO NEED TO MONITOR FOR POSSIBLE SNOW SQUALLS WITH
THE FRONT...THOUGH WINDS BEHIND THIS SYSTEM NOT AS STRONG.
SATURDAY AND SUNDAY...
SOME QUESTION AS TO HOW THE NEXT HIGH PRES ORIENTS ACROSS THE
NORTHEAST OR FURTHER N...AND A POSSIBLE LOW THAT MIGHT DEVELOP IN
THE SOUTHERN STREAM. HAVE KEPT CONDITIONS DRY FOR NOW...BUT
SOMETHING TO MONITOR. TEMPS ALSO SLOW MODERATE...THOUGH REMAIN
BELOW NORMAL.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH TUESDAY/...
THIS AFTERNOON...MAINLY VFR AND GUSTY WNW WINDS UP TO 40 KT. LOW
RISK OF BRIEF MVFR IN ISOLATED/WIDELY SCATTERED SNOW
SHOWERS/SQUALLS. MODERATE FORECAST CONFIDENCE.
TONIGHT...ANY LINGERING SNOW SHOWERS/SQUALLS AT SUNSET FIZZLE
AND/OR EXIT THE SOUTH COAST AND GIVE WAY TO VFR/DRY WEATHER ALONG
WITH DIMINISHING WINDS. HIGH FORECAST CONFIDENCE.
TUESDAY...MARGINAL VFR-MVFR IN MAINLY LIGHT SNOW. FAIRLY LIGHT
WINDS. MODERATE FORECAST CONFIDENCE.
KBOS TERMINAL...ONLY UNCERTAINTY IN FORECAST IS EXACT TIMING OF
POTENTIAL SNOW SHOWERS/SQUALLS INCLUDING AREAL COVERAGE AND
INTENSITY.
KBDL TERMINAL...ONLY UNCERTAINTY IN FORECAST IS EXACT TIMING OF
POTENTIAL SNOW SHOWERS/SQUALLS INCLUDING AREAL COVERAGE AND
INTENSITY.
OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...MODERATE CONFIDENCE.
TUE NIGHT...MAINLY VFR CIGS. MAY SEE LOCAL MVFR CONDITIONS LINGER
ACROSS CAPE COD AND NANTUCKET AS LIGHT SNOW LINGERS.
WED...MAINLY VFR CIGS. MAY SEE BRIEF PERIODS OF MVFR-IFR
CIGS/VSBYS IN LOCALLY HEAVY SNOW SQUALLS ALONG ARCTIC FRONT WED
AFTERNOON/EVENING. EXPECT NW WINDS TO INCREASE WED AFTERNOON...
GUSTING TO 30-40 KT AND CONTINUING INTO WED NIGHT.
THU...VFR. DIMINISHING WIND.
THU NIGHT AND FRI...MAINLY LOW END VFR CONDITIONS BUT WILL SEE
PATCHY MVFR DEVELOPING IN SCT SNOW SHOWERS. OCEAN EFFECT SNOW
POSSIBLE ALONG THE S COAST. GUSTY SW WINDS DEVELOPING LATE THU
NIGHT AND FRI WITH GUSTS TO 30-35 KT.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH TUESDAY/...MODERATE TO HIGH CONFIDENCE.
THIS AFTERNOON...WNW GALES WITH A LOW RISK OF A FEW SNOW
SHOWER/SQUALLS...GREATER RISK OFFSHORE. ROUGH SEAS SOUTH COAST
FROM LEFTOVER SSW SWELLS COMBINED WITH LONGER WESTERLY FETCH FOR
WIND WAVES.
TONIGHT...WINDS DIMINISH AS HIGH PRES BUILDS OVER NEW ENGLAND.
TUESDAY...LIGHT WINDS WITH LOWERING SEAS. VSBY MAY LOWER IN
PERIODS OF LIGHT SNOW/FLURRIES.
OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...HIGH CONFIDENCE.
TUESDAY NIGHT...WINDS AND SEAS BELOW SCA. REDUCED VSBYS IN LIGHT
SNOW.
WED AND THU...STRONG COLD ADVECTION WILL LIKELY RESULT IN ANOTHER
PERIOD OF NW GALES LATE WED THROUGH WED NIGHT...LINGERING INTO
THU MORNING BEFORE WINDS BRIEFLY DIMINISH. MODERATE FREEZING
SPRAY DEVELOPING WED NIGHT INTO THU AS ARCTIC AIR MOVES OVER THE
WATERS.
THU NIGHT AND FRI...ANOTHER PERIOD OF GALES LIKELY LATE THU
NIGHT INTO FRI ON SW FLOW. GUSTS TO 40 KT POSSIBLE.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...WIND ADVISORY UNTIL 7 PM EST THIS EVENING FOR CTZ002>004.
MA...WIND ADVISORY UNTIL 7 PM EST THIS EVENING FOR MAZ002>024-026.
RI...WIND ADVISORY UNTIL 7 PM EST THIS EVENING FOR RIZ001>008.
MARINE...GALE WARNING UNTIL 10 PM EST THIS EVENING FOR ANZ230>235-237-
254>256.
GALE WARNING UNTIL 6 PM EST THIS EVENING FOR ANZ236.
GALE WARNING UNTIL 1 AM EST TUESDAY FOR ANZ250-251.
&&
$$
SYNOPSIS...NOCERA/EVT
NEAR TERM...NOCERA/EVT/NMB
SHORT TERM...NOCERA
LONG TERM...EVT
AVIATION...NOCERA/EVT/NMB
MARINE...NOCERA/EVT/NMB
AREA FORECAST DISCUSSION
NWS ALBANY NY
1110 PM EST SUN JAN 4 2015
.SYNOPSIS...
ONE COLD FRONT HAS ALREADY CROSSED OUR REGION. ANOTHER COLD FRONT
WILL CROSS THE REGION TOWARD DAYBREAK. THIS WILL BE THE ONE THAT
REALLY BRINGS THE COLD AIR ALONG WITH MORE GUSTY WINDS AND
ADDITIONAL SHOWERS OF MOSTLY SNOW...MAINLY NORTHWEST OF ALBANY.IT
WILL BE BLUSTERY AND COLD MONDAY. A CLIPPER LOOKS TO BRING A LITTLE
SNOW ON TUESDAY FOLLOWED BY EVEN COLDER WEATHER WEDNESDAY AND
THURSDAY.
&&
.NEAR TERM /THROUGH MONDAY/...
AS OF 945 PM EST...A COLD FRONT HAS SLIPPED THROUGH MOST OF OUR
REGION. HOWEVER...AS THE RIGHT REAR REGION OF A 150KT JET HAS WORKED
INTO OUR REGION...IT HAS ALLOWED ANOTHER AREA OF SHOWERS TO EXPAND
IN OUR SOUTHEAST ZONES. HAD TO INCREASE POPS IN THAT THAT AREA FOR
AWHILE THIS EVENING. THIS RR REGION WILL SHIFT TO OUR SOUTH AFTER MIDNIGHT
TAKING THOSE SHOWERS WITH IT.
MEANWHILE...A SECONDARY COLD FRONT...THE ONE WITH ARCTIC AIR...WAS
WORKING INTO WESTERN NEW YORK. THIS FRONT WILL CROSS OUR REGION
TOWARD DAYBREAK BRINGING PERHAPS A STRAY SHOWER ON ITS OWN...ALONG
WITH MORE GUSTY WINDS AND THE REAL TEMPERATURE CHANGE. FOR THIS
UPDATE...TRENDED HOURLY TEMPERATURES UPWARD A BIT AS THEY WILL ONLY
SLOWLY FALL THROUGH THE EARLY OVERNIGHT...NOT FALLING TO BELOW
FREEZING UNTIL DAYBREAK...FROM THE HUDSON VALLEY EASTWARD.
TEMPERATURES WERE CLOSE TO FREEZING ACROSS THE ADIRONDACKS...AND WILL DROP
BELOW FREEZING ACROSS THE REMAINDER OF THE HIGHER TERRAIN SHORTLY
AFTER MIDNIGHT.
LAKE EFFECT SHOWERS WERE BEGINNING TO WORK INTO THE
ADIRONDACKS...PROBABLY A SNOW RAIN MIX IN THE VALLEYS...ALL SNOW
HIGHER TERRAIN...BUT WILL SWITCH TO ALL SNOW BY MIDNIGHT. WE WILL
KEEP ALL ADVISORIES UP THE WAY THEY WERE HANDED TO US.
BY DAYBREAK...LOWS WILL BE DOWN NEAR 20 ACROSS THE DACKS AND MUCH OF
THE REMAINDER OF THE ELEVATED TERRAIN. VALLEY AREAS WILL BE CLOSER
TO 30.
&&
.SHORT TERM /MONDAY NIGHT/...
LAKE EFFECT SNOW ADVISORY ISSUED FROM 7 PM SUNDAY TO 7 AM
MONDAY FOR NORTHERN HERKIMER AND HAMILTON COUNTIES...
...LAKE EFFECT SNOW ADVISORY ISSUED FROM 4 AM MONDAY TO 7 PM
MONDAY FOR SOUTHERN HERKIMER...FULTON AND MONTGOMERY COUNTIES.
THE ADVISORIES ARE FOR SNOW AND BLOWING SNOW WITH GUSTY WINDS OF
35 TO 45 MPH.
OUR CONFIDENCE WAS NOT GREAT ENOUGH TO ISSUE A WIND ADVISORY FOR
PARTS OF THE REGION SUNDAY NIGHT...THOUGH A 3RD PERIOD ADVISORY
MAY BE NEEDED FOR MONDAY...AS BETTER MOMENTUM TRANSFER IS
EXPECTED...BUT FOR NOW WIDESPREAD 46-57 MPH WIND GUSTS ARE NOT
ANTICIPATED FOR SUNDAY NIGHT INTO MONDAY. THIS WILL CONTINUE TO BE
MONITORED.
TONIGHT...COLD FRONT MOVES ACROSS THE REGION WITH STRONG LOW LEVEL
COLD ADVECTION EXPECTED. WESTERLY UPSLOPE SNOW SHOWERS WILL
INITIALLY IMPACT THE WRN DACKS AND SRN GREENS MTNS WITH MORE SCT
RAIN AND SNOW SHOWER ACTIVITY AWAY FROM THESE AREAS.
THE LATEST HIRES WRF AND 3-KM HRRR INDICATE A TRANSITION FROM THE
WESTERLY UPSLOPE SNOW SHOWERS OVER THE WRN DACKS TO AN ORGANIZED
SINGLE BAND. BUFKIT PROFILES JUST DOWNSTREAM OF LAKE ONTARIO
INDICATED MODERATE INSTABILITY WITH AN INVERSION HEIGHT CLOSE TO
10 KFT. HOWEVER...THE BAND IS EXPECTED TO FORM AND QUICKLY
TRANSITION S/SE WITH THE STRONG VEERING WIND PROFILE IN THE
BOUNDARY LAYER. THE LOW LEVEL FLOW STARTS AT 260-270 DEGS AND THEN
SHIFTS TO A 280 TO 290 DEG LOW-LEVEL TRAJECTORY. A QUICK BLAST OF
HVY SNOW SHOWERS IS ANTICIPATED FOR THE WRN DACKS WITH 3 TO 6
INCHES OF SNOW WITH PERHAPS SOME 4 TO 8 INCH AMOUNTS JUST SOUTH OF
OLD FORGE AND INLET. THE TRANSITORY BAND MOVES INTO SRN HERKIMER
COUNTY...AND THE W-CNTRL MOHAWK VALLEY BTWN 4-7 AM. THE NAM AND
HIRES WRF SHOW A MULTI-LAKE CONNECTION WITH MDT INSTABILITY CLASS
AT KUCA BUFKIT PROFILE. THIS AREA MAY NEED AN UPGRADE LATER...BUT
WE PUT THE ENTIRE W-CNTRL MOHAWK VALLEY CORRIDOR WAS ALSO PLACED
IN A LAKE EFFECT SNOW ADVISORY FOR SNOW AND BLOWING SNOW. ADVISORY
WIND LEVEL GUSTS WILL BE CLOSE WITH 35 TO 45 MPH GUSTS FORECASTED.
LOWS WILL BE MUCH COLDER IN THE TEENS TO M20S WITH SOME SINGLE
DIGITS OVER THE ADIRONDACK PARK...AND U20S OVER THE MID HUDSON
VALLEY.
MONDAY...THE BETTER PRESSURE RISES PASS NORTH OF ST LAWRENCE RIVER
VALLEY AND NRN NY BTWN 12Z-18Z MON 8-10 HPA/6 HRS. THE ISALLOBARIC
COUPLET IS IMPRESSIVE AS THE CYCLONE DEEPENS AND INTENSIFIES TO
ABOUT 980 HPA OVER THE GULF OF ST LAWRENCE BY 12Z/MON. SOME
SUSTAINED WESTERLY WINDS OF 15 TO 25 MPH WITH GUSTS 35 TO 45 MPH
ARE EXPECTED. THE 10-M WINDS ON THE GFSMOS PRODUCT FOR KALB ARE
IMPRESSIVE IN THE 18-24 KT SUSTAINED RANGE. THE BUFKIT MOMENTUM
TRANSFER PROFILES SHOW 40 KTS WILL NEED TO MIXED FROM 2.5 KFT AGL
FOR WIND ADVISORY CRITERIA TO BE MET. ANY WIND FLAGS WILL BE
MONITORED BY LATER SHIFTS. IT DOES LOOK PLAUSIBLE THAT SOME LAKE
EFFECT SHOWERS MAY SNEAK DOWN THE MOHAWK RIVER VALLEY INTO THE
CAPITAL REGION AND NRN TACONICS. HIGH CHC AND LIKELY POPS WERE USED
LATE MONDAY MORNING INTO THE PM FOR A COATING TO PERHAPS A HALF AN
INCH OF SNOW. SOME OF THE UPSLOPE AREAS OF THE SRN GREENS IN THE
SRN VT...TACONICS...AND NRN BERKS COULD GET AN INCH OR TWO OR
SNOW. THE ADVISORY AREA HIGHLIGHTED WILL LIKELY RECEIVE 3 TO 6
INCHES WITH SOME ISOLATED 4 TO 8 INCH AMOUNTS. THE INVERSION
HEIGHTS DO LOWER IN THE AFTERNOON...AND THE SHEAR INCREASES SO THE
DOWNSTREAM TRAJECTORY WILL DECREASE. MAX TEMPS MAY BE IN THE
MORNING...AND TEMPS MAY CONTINUE TO FALL SLOWLY IN THE AFTERNOON
IN THE POTENT COLD ADVECTION REGIME...AS H850 TEMPS CRASH INTO THE
-17C TO -22C RANGE ACROSS THE FCST AREA. DAYTIME HIGHS WILL BE IN
THE M20S TO L30S FROM THE TRI CITIES SOUTH AND EAST...AND TEENS TO
L20S NORTH AND WEST WITH SOME SINGLE NUMBERS OVER THE SRN DACKS.
WIND CHILLS WILL RANGE FROM 10 BELOW TO 10 ABOVE ZERO.
MONDAY NIGHT...LAKE EFFECT SNOW BAND LIFTS BACK NORTHWARD...AS THE FLOW
BACKS WITH AN APPROACHING SHORT-WAVE/CLIPPER LOW FROM THE GREAT
LAKES REGION AND MIDWEST. HIGH PRESSURE BRIEFLY BUILDS IN FROM
QUEBEC WITH A VERY COLD NIGHT EXPECTED. THE WINDS SHOULD
DIMINISH...AND FRIGID TEMPS ARE ANTICIPATED WITH LOWS BELOW ZERO
OVER THE SRN DACKS...AND PARTS OF THE LAKE REGION REGION...AND
ZERO TO 10 ABOVE IN MOST OTHER LOCATIONS WITH SOME LOWER TEENS IN
THE CAPITAL DISTRICT AND MID HUDSON VALLEY.
CLOUDS WILL INCREASE IN THE FRIGID AIR MASS WITH THE BETTER CHANCE
FOR LIGHT SNOW AND SCT SNOW SHOWERS ON TUE.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
OVERALL TEMPERATURES WILL BE WELL BELOW NORMAL DURING THE EXTENDED
PERIOD. PRECIPITATION GENERALLY BE BELOW NORMAL DESPITE DEALING WITH
A LOT OF DISTURBANCES RIPPLING THROUGH THE POLAR JET.
WEDNESDAY...WE WILL BE DEALING WITH FIRST SURGE OF ARCTIC AIR BEHIND
THE CLIPPER SYSTEM. HOWEVER...A SECONDARY COLD FRONT LOOKS TO WORK
THROUGH THE REGION DURING THE DAY...WITH MORE SCATTERED SNOW SHOWERS
AND POSSIBLY MORE DISRUPTIVE SNOW SQUALLS. WE WILL HAVE TO MONITOR
IF ANY OF THESE COME TO FRUITION AS THEY COULD CAUSE VERY BRIEF
REDUCTIONS IN VISIBLITY AND QUICKLY TURN ROADS INTO ICE SKATING
RINKS. IF THEY DO...WE WILL ISSUE SPECIAL WEATHER STATEMENTS AS
NEEDED.
EITHER WAY...THE COLDEST WEATHER OF THE WINTER WILL POUR IN BEHIND
THE COLD...AS THE AIR...TAPPED STRAIGHT FROM NORTHERN CANADA...WILL
DRIVE H850 TEMPERATURES TO BETWEEN -25C AND -30C OVER OUR REGION.
BTW...THE LAST TIME H850 TEMPERATURES WERE MEASURED AT -30C AT
ALBANY WAS JAN 16 2004. THEY COULD GET VERY CLOSE TO THESE VALUES ON
THURSDAY MORNING!
AFTERWARDS...THE ARCTIC AIR WILL MODERATE A BIT FRIDAY BEFORE
ANOTHER CLIPPER AND PERHAPS A WEAK COASTAL STORM...BRING A
REINFORCING SHOT OF LESS COLD FOR EARLY NEXT WEEK.
A NORTHWESTERLY TO WESTERLY FLOW OF EXTREMELY COLD AIR WORKING OVER
THE RELATIVELY WARM LAKE WATERS...WILL LIKELY TRIGGER BANDS OF LAKE
EFFECT SNOW OFF ONTARIO...VACILLATING BETWEEN THE
ADIRONDACKS...MOHAWK AND CATSKILLS...AND EVEN OCCASIONALLY DUCTING
ENOUGH MOISTURE FOR UPSLOPE SNOW SHOWERS ACROSS THE SOUTHERN GREENS.
THESE BANDS COULD BRING SEVERAL INCHES OF SNOWFALL IN SPOTS DOWNWIND
OF ONTARIO AND PERHAPS THE SOUTHERN GREENS.
MOST OF THE REMAINDER OF THE REGION WILL BE DRY WEDNESDAY NIGHT
THROUGH FRIDAY WITH PARTIAL SUNSHINE...WITH PERHAPS A FEW
FLURRIES.
AGAIN...THE BIG NEWS WILL BE BRUTAL COLD...ESPECIALLY WEDNESDAY
NIGHT INTO THURSDAY WHEN TEMPERATURES ARE FORECAST TO PLUMMET TO
NEAR ZERO IN THE HUDSON VALLEY SOUTH OF ALBANY...ZERO TO 10 BELOW
CAPITAL REGION AND SURROUNDING AREAS...AND AS LOW AS 20 BELOW ACROSS
THE ADIRONDACKS. THIS ARE THE ACTUAL TEMPERATURES. WHEN ONE FACTORS
IN A NORTHWEST WIND OF 10-15 MPH...WIND CHILL VALUES WILL BE DRIVEN
TO DANGEROUSLY LOW LEVEL AS LOW AS -25 TO -40 DEGREES!!! WIND CHILL
HEADLINES WILL LIKELY BE ISSUED WEDNESDAY INTO THURSDAY MORNING TO
COVER THIS DANGEROUS COLD.
HIGHS ON THURSDAY WILL STRUGGLE TO GET OUT OF THE SINGLE NUMBERS
NORTH...AND ONLY REACH INTO THE TEENS FROM THE CAPITAL REGION
SOUTHWARD. THE WIND WILL ABATE SO EVENTUALLY BY THURSDAY
AFTERNOON...WIND CHILLS WILL NOT BE AS HARSH.
WARM AIR ADVECTION ON THE BACK SIDE OF HIGH PRESSURE WILL BRING
CLOUDS AND PERHAPS SOME SNOW SHOWERS THURSDAY NIGHT INTO FRIDAY.
TEMPERATURES WILL NOT DROP MUCH THURSDAY NIGHT AND THEN RISE BACK
INTO THE TEENS NORTH AND 20S SOUTH ON FRIDAY.
WEAK HIGH PRESSURE SHOULD REBUILD BACK IN ON SATURDAY WITH
TEMPERATURES SIMILAR TO FRIDAY AND LINGERING SNOW SHOWERS TO THE LEE
OF ONTARIO.
BY SUNDAY...WE WILL HAVE TO WATCH TO SEE IF A STORM DEVELOPS ALONG
THE EASTERN SEABOARD. RIGHT NOW IF IT DOES...IT LOOKS WEAK AND MIGHT
HEAD OUT TO SEA...BUT BEARS WATCHING. FOR NOW...WE WILL ASSIGN A
SLIGHT CHANCE OF SNOW WITH A MOSTLY CLOUDY SKY. HIGH TEMPERATURES
WILL MODERATE BACK CLOSER TO NORMAL...BUT STILL BELOW FREEZING
EVERYWHERE ACROSS OUR REGION.
&&
.AVIATION /04Z MONDAY THROUGH FRIDAY/...
AS OF 1000 PM...CONDITIONS HAVE IMPROVED TO MVFR OR VFR AT ALL OF
OUR TAF SITES. SHOWERS LOOK TO STILL IMPACT MAINLY KPOU AND KPSF
WITH OCCASIONAL MVFR CONDITIONS THROUGH ABOUT MIDNIGHT.
OTHERWISE...WITH THE POSSIBLE EXCEPTION OF KPSF...WE WILL HAVE
MAINLY VFR CONDITIONS THROUGH MONDAY...MVFR AT KPSF.
MONDAY AT KALB...AS A LAKE BAND OFF ONTARIO MIGHT IMPACT THE AIRPORT
BETWEEN ABOUT 15Z-19Z. WE ASSIGNED A PROB30 FOR IFR SNOW SHOWERS
(2SM -SHSN). AT KGFL AND KPSF WE ASSIGNED A VCSH AS THE THREAT OF
MVFR SNOW SHOWERS WAS VERY LOW (ONLY ABOUT 25 PERCENT).
AGAIN OUTSIDE OF ANY SNOW SHOWER ACTIVITY...THE MAJORITY OF THE TIME
SHOULD BE VFR AT ALL TAF SITES MONDAY. AGAIN...A GUSTY WIND COULD
CAUSE MECHANICAL TURBULENCE.
OUTLOOK...
MON NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
TUE: HIGH OPERATIONAL IMPACT. LIKELY SN.
TUE NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN.
WED: MODERATE OPERATIONAL IMPACT. BREEZY. CHANCE OF SHSN.
WED NIGHT: LOW OPERATIONAL IMPACT. BREEZY.
THU: NO OPERATIONAL IMPACT. NO SIG WX.
THU NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHSN.
FRI: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
A COMPLEX STORM SYSTEM WITH MODERATE TO HEAVY QPF WILL MOVE ACROSS
THE HSA THROUGH TODAY.
MOST AREAS ARE FORECAST TO RECEIVE 1-2 INCHES OF LIQUID
EQUIVALENT PRECIPITATION...WITH LOCALLY IN EXCESS OF TWO INCHES.
THIS WILL ALLOW FOR SIGNIFICANT RISES ON RIVERS AND STREAMS ON
SUNDAY...AS TEMPERATURES RISE ABOVE FREEZING BRIEFLY OVER THE
ENTIRE REGION.
ISOLATED MINOR FLOODING IS POSSIBLE AND PER COLLABORATION
YESTERDAY WITH THE NERFC...THE HSA POINTS THAT GOES ABOVE ACTION
STAGE ARE WILLIAMSTOWN /WILM3/...AND GRANVILLE /GVVN6/ AT THIS
TIME. SINCE THE POTENTIAL OF WIDESPREAD MINOR FLOODING IS NOT
EXPECTED...A FLOOD WATCH HAS NOT BEEN ISSUED AT THIS TIME.
LAKE EFFECT SNOWFALL WILL IMPACT LOCATIONS NORTH AND WEST OF THE
CAPITAL REGION TONIGHT THROUGH MONDAY IN THE WAKE OF A STRONG COLD
FRONT.
THEREAFTER...BITTER COLD WEATHER IS EXPECTED NEXT WEEK. SOME
FREEZE UP ICE JAMS ARE POSSIBLE ACROSS THE SOUTHWESTERN
ADIRONDACKS AND SOUTHERN VERMONT BY LATE IN THE WEEK.
OTHERWISE...ICE WILL LIKELY DEVELOP AND INCREASE ACROSS RIVERS
AND STREAMS.
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...LAKE EFFECT SNOW ADVISORY FROM 4 AM TO 7 PM EST MONDAY FOR
NYZ038>040-082.
LAKE EFFECT SNOW ADVISORY UNTIL 9 AM EST MONDAY FOR NYZ032-033.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...HWJIV/BGM
NEAR TERM...HWJIV
SHORT TERM...BGM/WASULA
LONG TERM...HWJIV
AVIATION...HWJIV
HYDROLOGY...BGM/WASULA
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
730 PM EST TUE JAN 6 2015
.UPDATE (REST OF TONIGHT THROUGH WEDNESDAY NIGHT)...
00Z WATER VAPOR AND H4 RAP ANALYSIS SHOWING THE NORTHERN STREAM FLOW
RIDGING UP OVER THE PACIFIC COAST / INTERMOUNTAIN WEST BEFORE
CARVING OUT A BROAD LONGWAVE TROUGH THROUGH THE UPPER MIDWEST/GREAT
LAKES/ AND NORTHEASTERN PORTION OF THE COUNTRY. THIS FLOW SEPARATES
THE COOL AIR ACROSS THE SOUTH...FROM THE FRIGID ARCTIC AIR FURTHER
TO THE NORTH. OUR FORECAST AREA IS STILL UNDER A MORE ZONAL FLOW
CONFIGURATION BETWEEN THIS TROUGH TO OUR NORTH AND A LARGE RIDGE OF
UPPER LEVEL HIGH PRESSURE ACROSS THE NW CARRIBEAN.
SHORTWAVE ENERGY EMBEDDED WITHIN THE NORTHERN STREAM FLOW CURRENTLY
DROPPING SOUTH INTO THE UPPER MIDWEST WILL PLAY AN IMPORTANT ROLE IN
OUR FORECAST AS IT QUICKLY PIVOTS TO THE SOUTHEAST DURING WEDNESDAY
AND AMPLIFIES THE TROUGH INTO THE SOUTHEASTERN CONUS. THIS
AMPLIFICATION WILL DRIVE A STRONG COLD FRONT SOUTHWARD THROUGH THE
SOUTHEAST ON WEDNESDAY AND THROUGH THE FLORIDA PENINSULA WEDNESDAY
EVENING AND NIGHT.
THE BRUNT OF THE ARCTIC AIR WILL BE PUSHING OFF THE ATLANTIC
SEABOARD TO THE NORTH OF THE FLORIDA PENINSULA...HOWEVER WE WILL
STILL SEE A SURGE OF COLDER AIR ARRIVING FROM THE NORTH WEDNESDAY
NIGHT...AND IT WILL BE NOTICEABLY COLDER BY THE TIME EVERYONE WAKES
UP EARLY THURSDAY MORNING. MORE DETAILS ON THIS COLD SHOT BELOW.
CURRENTLY AT THE SURFACE...HIGH PRESSURE IS BEGINNING TO NOSE INTO
THE REGION FROM THE NORTHWEST. THIS SURFACE RIDGE ALONG WITH NO
SIGNIFICANT SYNOPTIC LIFT TO SPEAK OF WILL KEEP OUR FORECAST DRY
TONIGHT AND WEDNESDAY. SEASONABLE TEMPERATURES ARE EXPECTED THROUGH
WEDNESDAY WITH UPPER 30S TO LOWER 40S NORTH OF THE I-4 CORRIDOR AND
MIDDLE 40S TO MIDDLE 50S HEADING FURTHER SOUTH DOWN THE PENINSULA BY
SUNRISE ON WEDNESDAY. TEMPERATURES WILL REBOUND UNDER A MIX OF SUN
AND HIGH CLOUDS INTO THE LOWER/MID 60S NORTH AND UPPER 60S TO LOWER
70S SOUTH. THE COLD FRONT WILL JUST BE ARRIVING ACROSS OUR NORTHERN
AREAS EARLY WEDNESDAY EVENING...AND WILL THEN MAKE QUICK PROGRESS
SOUTHWARD AS WE HEAD INTO THE NIGHT. DESPITE THE STRONG NATURE OF
THE FRONT...THE ATMOSPHERE SIMPLY DOES NOT COME TOGETHER TO PRODUCE
CONDITIONS SUPPORTIVE OF SHOWERS...SO WILL BE LOOKING FOR A DRY
FRONTAL PASSAGE.
STRONG CONTINENTAL HIGH PRESSURE BUILDS OVER THE SOUTHEAST U.S. AND
FLORIDA WEDNESDAY NIGHT IN THE WAKE OF THE COLD FRONT. STRONG CAA
ADVECTION WILL OCCUR ACROSS WEST CENTRAL AND SOUTHWEST FLORIDA ON
INITIALLY GUSTY NORTH WINDS...WHICH WILL BE VEERING TO THE NORTHEAST
AND SETTLING DOWN A BIT LATE AT NIGHT. THE LOWER ATMOSPHERIC COLUMN
BEHIND THIS FRONT IS ONE THAT SHOWS A CLASSIC ARCTIC
CONFIGURATION...WITH THE COLDEST TEMPERATURES JUST ABOVE THE
SURFACE...AS OPPOSED TO OUR NORMAL COLD FRONT WHERE THE COLDER
AIRMASS IS GENERALLY ALOFT. GFS/ECMWF BOTH SHOWING AN INVERTED
TEMPERATURE PROFILE BY SUNRISE ON THURSDAY...WITH VALUES DOWN BELOW
ZERO (-2 TO -4C) ACROSS THE NATURE COAST AT 950MB...WHILE AT 850MB
TEMPS ARE RANGING FROM 2 TO 5C. THIS IS A GOOD SETUP FOR THE
ADVECTION OF COLD AIR...AND AN ADVECTIVE FREEZE IS BECOMING MORE
LIKELY LATE WEDNESDAY NIGHT INTO EARLY THURSDAY MORNING FROM AROUND
THE BROOKSVILLE AREA AND NORTHWARD. A FREEZE WATCH IS NOW IN EFFECT
WEDNESDAY NIGHT FOR HERNANDO... SUMTER...CITRUS...AND LEVY COUNTIES.
ALTHOUGH CURRENT FORECAST DOES NOT SUPPORT A HARD FREEZE ACROSS LEVY
COUNTY...ANY FURTHER DECREASE IN THE TEMPERATURE FORECAST COULD
RESULT IN AN UPGRADE FROM FREEZE TO HARD FREEZE. WILL CONTINUE TO
MONITOR THE LATEST GUIDANCE TRENDS. BREEZY CONDITIONS WILL ALSO LEAD
TO LOW WIND CHILL VALUES WEDNESDAY NIGHT ACROSS MUCH OF THE REGION.
ALTHOUGH IT IS STILL TOO EARLY FOR ISSUING ADVISORIES...THE CURRENT
FORECAST WOULD SUPPORT WIND CHILL ADVISORIES CRITERIA LATER
WEDNESDAY NIGHT / THURSDAY MORNING OVER MUCH OF REGION. IN FACT...
THE ONLY COUNTIES THAT WOULD NOT FALL UNDER THE ADVISORY CRITERIA
BASED ON THE CURRENT FORECAST WOULD BE CHARLOTTE AND LEE COUNTIES
WHERE LOWEST WIND CHILLS VALUES LATE WEDNESDAY NIGHT ARE IN THE
MID/UPPER 30S.
THE INVERTED TEMPERATURE PROFILE WILL ALSO DISCOURAGE DIURNAL MIXING
ONCE THE SUN COMES UP ON THURSDAY...AND THEREFORE UNTIL THE
AFTERNOON WHEN THE TRUE CAA HAS CEASED...WE CAN EXPECT OUR USUAL
MORNING TEMPERATURE RISE TO INITIALLY STRUGGLE.
&&
.AVIATION...
VFR CONDITIONS EXPECTED TO PREVAIL FOR THE DURATION OF THE TAF
PERIOD. GENERALLY LIGHT NORTHERLY WINDS THROUGH WEDNESDAY AFTERNOON.
&&
.MARINE...
A STRONG AREA OF HIGH PRESSURE WILL SLOWLY BUILD IN TO THE NORTH OF
THE REGION THROUGH WEDNESDAY MORNING. A STRONG COLD FRONT WILL THEN
CROSS THE EASTERN GULF OF MEXICO LATER WEDNESDAY WITH WINDS AND SEAS
QUICKLY INCREASING IN ITS WAKE. NORTHERLY WINDS WILL INCREASE TO
BETWEEN 20 AND 30 KNOTS WEDNESDAY NIGHT WITH FREQUENT GUSTS TO GALE
FORCE POSSIBLE...WHILE SEAS BUILD TO BETWEEN 6 AND 8 FEET NEAR SHORE
AND 8 TO 11 FEET OFFSHORE. THESE HAZARDOUS CONDITIONS WILL CONTINUE
INTO THURSDAY MORNING BEFORE WINDS AND SEAS BEGIN TO RELAX LATER
THURSDAY INTO FRIDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 51 65 38 59 / 0 0 0 0
FMY 59 73 46 67 / 0 0 0 0
GIF 49 66 37 60 / 0 0 0 0
SRQ 53 66 41 62 / 0 0 0 0
BKV 41 63 32 55 / 0 0 0 0
SPG 55 63 42 58 / 0 0 0 0
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...FREEZE WATCH FROM LATE WEDNESDAY NIGHT THROUGH THURSDAY
MORNING FOR COASTAL CITRUS-COASTAL HERNANDO-COASTAL
LEVY-INLAND CITRUS-INLAND HERNANDO-INLAND LEVY-SUMTER.
GULF WATERS...GALE WATCH FROM WEDNESDAY EVENING THROUGH THURSDAY
MORNING FOR BONITA BEACH TO ENGLEWOOD OUT 20 NM-BONITA BEACH
TO ENGLEWOOD OUT 20 TO 60 NM-ENGLEWOOD TO TARPON
SPRINGS OUT 20 NM-ENGLEWOOD TO TARPON SPRINGS OUT 20
TO 60 NM-TARPON SPRINGS TO SUWANNEE RIVER OUT 20 NM-
TARPON SPRINGS TO SUWANNEE RIVER OUT 20 TO 60 NM.
&&
$$
UPDATE/AVIATION/MARINE...MROCZKA
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
345 PM EST MON JAN 5 2015
.DISCUSSION...
TONIGHT-TUESDAY...
QUIET WX PATTERN IN STORE FOR CENTRAL FL AS THE COLD FRONT STALLS
AND WASHES OUT OVER THE S PENINSULA. LATEST RUC ANALYSIS SHOWS A
VERY STABLE H85-H70 LYR WITH LAPSE RATES BLO 4.0C/KM...AS LOW AS
2.5C/KM DIRECTLY OVERHEAD JUST S OF THE I-4 CORRIDOR. VERY LOW
ENERGY AIRMASS OVERHEAD AND UPSTREAM WITH NO SIG MID LVL VORT/OMEGA
MAXES...WEAK UPR LVL DIVERGENCE OVER THE NRN GOMEX/FL BIG BEND WILL
ONLY GENERATE MID/UPR LVL CLOUD COVER AT BEST. RADAR HAS INDICATED A
FEW SPRINKLES IN THE IMMEDIATE VCNTY OF THE FRONT THIS AFTN...BUT
EVEN THESE HAVE DISSIPATED OVER LAND NOW THAT THE FRONT HAS PUSHED S
OF THE LAKE.
WEAK BUT STUBBORN RIDGING OVER THE NRN BAHAMAS/FL STRAITS WILL BE
REINFORCED BY AN ANTICYCLONE OVER THE NW GULF COAST. THIS WILL
EFFECTIVELY BLOCK OUT ANY OF THE PENCIL THIN VORT ENERGY NOTED OVER
THE NRN GULF COAST. ANY ADDITIONAL PRECIP WILL BE LIMITED TO THE
GULF STREAM AND SHOULD DISSIPATE BY SUNSET...WILL KEEP THE FCST DRY.
MIN TEMPS WILL HAVE A FAIRLY WIDE SPREAD TONIGHT DESPITE THINNING
CLOUD COVER AS THE POST FRONTAL HI PRES RIDGE EXTENDING FROM THE RIO
GRANDE VALLEY TO THE GREAT LAKES PRESSES EWD AND WEAKENS. SFC WINDS
EXPECTED TO VEER TO AN ONSHORE COMPONENT NEAR THE COAST...KEEPING
THE SPACE/TREASURE COASTS IN THE L/M60S. LIGHTER WINDS AND COOLER
SHELF WATERS OFF VOLUSIA COUNTY WILL ALLOW TEMPS TO FALL INTO THE
M/U50S. OVER THE INTERIOR...NRLY WINDS BCMG LIGHT AND VARIABLE AS
THE PGRAD WEAKENS...SHOULD GIVE WAY TO A LIGHT DRAINAGE FLOW THAT
WILL ALLOW MINS TO FALL INTO THE L50S N OF THE I-4 CORRIDOR...M/U50S
TO THE S...NEAR 60 ALONG THE N SHORE OF LAKE OKEECHOBEE.
LIMITED COOL AIR ADVECTION HAS OCCURRED WITH THIS FRONT...SFC
DEWPOINTS IN THE M/U40S N OF I-4 INCREASE TO THE M/U50S JUST S OF
IT...AND REMAIN IN THE L60S ALONG THE TREASURE COAST AND N SHORE OF
LAKE OKEECHOBEE. DESPITE A LIGHT NW FLOW THAT WILL DVLP BY MIDDAY...
THE HIGH DEWPOINTS WILL ALLOW MAX TEMPS TO WARM INTO THE L/M70S N OF
I-4...AND INTO THE M/U70S TO THE SOUTH.
WED/WED NIGHT...
UPPER LEVEL TROUGH DIGS SOUTHWARD ACROSS THE EASTERN U.S. AS STRONG
ARCTIC HIGH PRESSURE BUILDS DOWN FROM THE NORTHERN PLAINS INTO THE
MID-MISSISSIPPI VALLEY REGION. THIS LEADS TO A DRY COLD FRONTAL
PASSAGE ACROSS CENTRAL FLORIDA WITH COOL NORTHWEST FLOW AND
INCREASING HIGH CLOUDINESS DURING THE DAY. HIGHS WILL BE MID TO
UPPER 60S ORLANDO NORTH AND LOW TO MID 70S TREASURE COAST. STRONG
COLD AIR ADVECTION OCCURS WED NIGHT OVER THE INTERIOR BUT MODELS
SHOW QUICK VEERING OF THE 925-850 MB FLOW TO ONSHORE. THIS SHOULD
PRODUCE A TIGHT COASTAL/INLAND TEMP GRADIENT WED NIGHT/THU
MORNING...RANGING FROM THE MID 30S IN PORTIONS OF LAKE COUNTY TO THE
LOWER 50S IMMEDIATE COAST SOUTH OF THE CAPE. IT STILL APPEARS THAT
FREEZING TEMPERATURES WILL REMAIN NORTH OF OUR FA BUT NORTH WINDS
15-20 MPH WILL PRODUCE WIND CHILL VALUES BELOW FREEZING NORTH AND
WEST OF ORLANDO. SO WILL PROBABLY NEED A WIND CHILL ADVISORY THERE.
THU-SUN...
STRONG HIGH PRESSURE BUILDS INTO THE SOUTHEAST THU AND EXTENDS
OFFSHORE INTO LATE WEEK WITH LOW LEVEL NORTHERLY FLOW BECOMING
ONSHORE. ELEVATED NE FLOW ABOVE THE SFC THU WILL TRANSPORT MARINE
STRATOCU CLOUDS ONSHORE WITH ISOLATED COASTAL SHOWERS EXPECTED.
TEMPS WILL REMAIN BELOW NORMAL INTO LATE WEEK WITH HIGHS THU IN THE
50S NORTH OF MELBOURNE AND LOW-MID 60S SOUTH. MAX TEMPS FRI WILL
RANGE FROM THE 60S MOST AREAS TO LOW 70S ACROSS PORTIONS OF THE
TREASURE COAST. THEN INTO THE WEEKEND STRENGTHENING ONSHORE LOW
LEVEL FLOW WILL GRADUALLY WARM TEMPS WITH RAIN CHANCES INCREASING TO
20-30 PERCENT.
&&
.AVIATION...THRU 06/18Z
SFC WNDS: THRU 06/03Z...N/NE 8-14KTS...OCNL G22KTS CSTL SITES. BTWN
06/03Z-06/15Z...N/NW AOB 5KTS. AFT 06/15Z...NW 5-8KTS.
VSBYS/WX: BTWN 06/09Z-06/13Z...LCL MVFR BR.
CIGS: N OF KVRB-KOBE THRU 06/12Z...BTWN FL060-080 LCL BTWN
FL020-030...AFT 06/12Z AOA FL120. S OF KVRB-KOBE...THRU 06/06Z BTWN
FL040-060 AREAS BTWN FL010-020...AFT 06/06Z BTWN FL020-030...LCL BLO
FL010 THRU 06/12Z.
&&
.MARINE...
TONIGHT-TUESDAY...CHOPPY/ROUGH CONDITIONS MEASURED BY THE LCL BUOY
NETWORK...NEAR SCA CONDITIONS MEASURED BY THE CANAVERAL DATA BUOYS
WITH NRLY WINDS ARND 20KTS AND SEAS BTWN 5-7FT...SCRIPPS BUOYS
LOWER AT 3-5FT...BUT ALL RECORDING NEAR SQUARE SEAS WITH DOMINANT
PDS BTWN 5-6SEC.
MODERATE TO FRESH NRLY BREEZE BEHIND A COLD FRONT JUST S OF LAKE
OKEECHOBEE WILL DIMINISH OVERNIGHT AS THE POST FRONTAL RIDGE OVER
THE OH/TN/MS RIVER VALLEYS PUSHES TOWARD THE ERN SEABOARD AND
WEAKENS...SFC WINDS BCMG A LIGHT TO GENTLE ERLY BREEZE BY DAYBREAK.
LCL PGRAD WILL COLLAPSE AS THE FRONT WASHES OUT IN THE VCNTY OF LAKE
OKEECHOBEE...ALLOWING SFC/BNDRY LYR WINDS BCMG LGT/VRBL BY LATE TUE
MRNG. WINDS WILL THEN BACK TO THE N/NW AND INCREASE TO ARND 10KTS BY
SUNSET AS THE LEADING EDGE OF A NEW HIGH PRES RIDGE BEGINS TO NUDGE
ITS WAY INTO THE DEEP SOUTH. GIVEN THE CURRENT CONDITIONS...CURRENT
NEARSHORE CAUTION/OFFSHORE ADVISORY WILL CONTINUE THRU 10PM THIS
EVNG.
WED-FRI...STRONG AREA OF HIGH PRESSURE BUILDS DOWN FROM THE NORTHERN
PLAINS MID WEEK INTO THE SOUTHEAST U.S. BY THU-FRI. A COLD FRONT
WILL MOVE THROUGH THE WATERS WED WITH NORTHERLY WINDS QUICKLY
INCREASING BEHIND THE BOUNDARY INTO WED NIGHT. THIS WILL LEAD TO
VERY HAZARDOUS BOATING CONDITIONS ACROSS THE WATERS WITH WIND SPEEDS
25-30 KTS BUILDING SEAS UP TO 14 FEET IN THE GULF STREAM WED
NIGHT/THU. WINDS BEGIN TO DECREASE BUT REMAIN HAZARDOUS AS THEY VEER
TO THE NORTHEAST THU AFTN WITH A CONTINUED DECREASE FORECAST THU
NIGHT-FRI. SEAS WILL BE SLOW TO SUBSIDE INTO LATE WEEK WITH 7 FT
SEAS IN THE GULF STREAM STILL FORECAST ON FRI.
&&
.FIRE WEATHER...
DRIER AIR BUILDING INTO THE AREA WEDNESDAY WILL GENERATE MIN RH
VALUES BETWEEN 25 AND 30 PERCENT ACROSS NORTHERN AND INTERIOR
SECTIONS WEDNESDAY. NW WINDS WILL BE AROUND 10 MPH.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 51 71 47 65 / 10 10 0 10
MCO 53 77 51 67 / 10 10 10 10
MLB 59 76 57 69 / 10 0 10 10
VRB 62 78 57 71 / 10 0 10 10
LEE 49 72 47 65 / 10 10 0 10
SFB 52 75 49 66 / 10 10 10 10
ORL 53 76 51 66 / 10 10 10 10
FPR 62 78 58 72 / 10 0 10 10
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...SMALL CRAFT ADVISORY UNTIL 10 PM EST THIS EVENING FOR 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.
&&
$$
SHORT TERM/AVIATION...BRAGAW
LONG TERM/IMPACT WX...KELLY
AREA FORECAST DISCUSSION
NWS MIAMI FL
1252 PM EST MON JAN 5 2015
.AVIATION...
WEAK COLD FRONT GRINDING TO A HALT ACROSS THE LAKE REGION,
CURRENTLY. THE EVENTUAL RESTING PLACE OF THIS BOUNDARY WILL
DETERMINE IF OR WHEN MVFR CIGS DEVELOP DURING THE FORECAST. THE
TYPICALLY PESSIMISTIC LAMP GUIDANCE KEEPS CIGS ABV MVFR UNTIL
LATE TONIGHT, ALTHOUGH IS CURRENTLY MISSING CEILINGS AT KPBI. VERY
WELL COULD BE A FEW HOURS OF MVFR CIGS AT THE NORTHERN TERMINALS
THIS PM, BUT ANY LOWER CIGS FROM THE FRONT SHOULD STAY AWAY FROM
MORE SOUTHERN TERMINALS. FAIR INGREDIENTS FOR MVFR OR EVEN IFR
CIGS AT APF LATE TONIGHT, WITH THE BOUNDARY NEARBY. ALTHOUGH THE
LAMP INDICATES CHC EXISTS FOR MVFR CIGS AT OTHER TERMINALS LATE
TONIGHT, WILL KEEP ABV FOR NOW. IF THEY DEVELOP, SOME LOWER CIGS
COULD PERSIST INTO TUESDAY DEPENDING UPON WHERE THE DIFFUSE
BOUNDARY RESIDES.
&&
.PREV DISCUSSION... /ISSUED 953 AM EST MON JAN 5 2015/
UPDATE...
CURRENT ANALYSIS SHOWS DEEP LAYER RIDGE STRETCHING ACROSS THE
EXTREME SOUTHERN PORTION OF THE PENINSULA WITH A WEAK COLD FRONT
NEAR THE SOUTHERN SHORES OF LAKE OKEECHOBEE INCLUDING EXTREME
NORTHERN PALM BEACH AND HENDRY COUNTIES ALONG WITH GLADES COUNTY.
THE FRONT IS VERY SHALLOW AND IS MARKED BY A NEAR SOLID DECK OF
LOW STRATUS BEHIND THE LEADING EDGE OF THE BOUNDARY. THE FRONT
WILL NOT MAKE FURTHER PROGRESS SOUTHWARD STALLING NEAR ITS CURRENT
POSITION AND THEN BECOMING DIFFUSE AS THE MAIN UPPER TROUGH LIFTS
WELL TO THE NORTHEAST. THIS WILL LEAVE MOST OF SOUTH FLORIDA IN
THE WARM SECTOR THIS AFTERNOON AND WITH DEW POINTS IN THE UPPER
60S TO AROUND 70, HIGH RESOLUTION SHORT TERM MODEL GUIDANCE
SUGGEST A FEW SHOWERS OVER THE INTERIOR AND EAST COASTAL ZONES.
THE 12Z MFL SOUNDING ALSO SHOWS THE LOW LEVEL MOISTURE INCREASING
FROM YESTERDAY BUT THE STRONG SUBSIDENCE CAP WITH ITS BASE AT 7-8K
WILL KEEP THE SHOWERS LOW TOPPED.
KOB
PREV DISCUSSION... /ISSUED 624 AM EST MON JAN 5 2015/
AVIATION...
LIGHT TO MODERATE SHOWERS CONTINUE IN THE VICINITY OF ALL THE
ATLANTIC COAST TERMINALS AROUND 11Z AND ARE NEARLY STATIONARY.
BRIEF PERIODS OF NEAR MVFR CEILINGS ARE POSSIBLE THROUGH ABOUT
13Z AS THE SHOWERS ARE NEARLY STATIONARY. OTHERWISE...MAINLY VFR
CONDITIONS EXPECTED LATER THIS MORNING AND THIS AFTERNOON. WINDS
THIS MORNING ARE EXPECTED TO BE LIGHT AND VARIABLE WITH
NORTHEASTERLY WINDS BUILDING INTO THE REGION AROUND 18Z AHEAD OF A
COLD FRONT IN NORTH CENTRAL FLORIDA.
PREV DISCUSSION... /ISSUED 404 AM EST MON JAN 5 2015/
DISCUSSION...
A COLD FRONT IS CURRENTLY MAKING ITS WAY TOWARDS SOUTH FLORIDA AS
EXPECTED. IT IS CURRENTLY IN CENTRAL FLORIDA. AHEAD OF IT SOME
SHOWER ACTIVITY HAS ALREADY DEVELOPED, MAINLY ALONG THE ATLANTIC
COASTLINE. THE HRRR DOES SHOW THIS ACTIVITY ENDING OVER THE NEXT
COUPLE OF HOURS. SO, CONTINUE WITH SLIGHT CHANCE POPS OVER COASTAL
PALM BEACH COUNTY TO COVER ANY SHOWER ACTIVITY THAT PERSISTS.
ANOTHER CONCERN WITH THIS LINE OF CONVERGENCE ALONG THE COAST IS
WATERSPOUT ACTIVITY. ALTHOUGH THE BOUNDARY IS NOT PROMINENT ON
THE GULF COAST, CAN NOT RULE ONE OUT ACROSS ANY OF THE SOUTH
FLORIDA WATERS THIS MORNING.
COMPARING LAST NIGHTS SOUNDING AND THE WATER VAPOR IMAGERY, THE
MOISTURE LOOKS TO BE FAIRLY SHALLOW. THE SOUNDING SHOWS A STRONG
CAP IS IN PLACE AT AROUND 800MB. NAM MODEL SOUNDINGS SHOW IT
SHOULD HOLD, EVEN WITH THE FRONT APPROACHING. THE WATER VAPOR
IMAGERY IS SHOWING THAT THE MOISTURE IS REMAINING MAINLY OVER
NORTH FLORIDA AND SOUTH GEORGIA, WITH LITTLE PROGRESSION TO THE
SOUTH. SO, THIS WILL LEND CREDENCE TO THE LOW POPS THE MODELS ARE
FORECASTING FOR TODAY, WITH A LOW END CHANCE OVER THE A PORTION OF
THE CWA THIS AFTERNOON.
THE FRONT WILL SLOWLY PROGRESS TO THE SOUTH, THROUGH THE CWA
TODAY, AS THE MAIN LOW IS WELL AWAY FROM THE AREA, NORTHEAST OF
MAINE, AND PULLING AWAY. MODELS SHOW THE FRONT WILL MAKE IT
THROUGH MOST OF SOUTH FLORIDA AND PERHAPS TO THE KEYS BEFORE
STALLING OUT. IT WILL THEN REMAIN THROUGH WEDNESDAY AS A WEAK
BOUNDARY, KEEPING A SLIGHT CHANCE OF SHOWERS IN THE FORECAST FOR
PORTIONS OF THE CWA UNTIL WEDNESDAY EVENING. EVEN THAT WILL BE
MORE OR LESS ALONG THE ATLANTIC COAST AND OVER THE ATLANTIC
WATERS. HIGH PRESSURE WILL BUILD IN OVER THE SOUTH EASTERN US, BUT
NEVER DIG FAR ENOUGH SOUTH TO PUSH THE FRONT AWAY FROM THE AREA.
MEANWHILE, ANOTHER LOW WILL MOVE OUT OF THE ROCKIES TODAY AND
QUICKLY MOVE INTO THE PLAINS. MODELS INDICATE IT SHOULD BE OVER
THE MISSISSIPPI VALLEY TONIGHT AND THEN APPEAR TO WASH OUT AS IT
MOVES ACROSS THE APPALACHIANS. MODELS SHOW IT WILL REFORM OFF THE
MID ATLANTIC COAST TUESDAY NIGHT AND BEGIN TO INTERACT WITH THE
STALLED BOUNDARY. AS IT DOES, AS VERY STRONG HIGH WILL MOVE OUT OF
WESTERN CANADA AND INTO THE PLAINS. THIS HIGH WILL WORK WITH THE
LOW TO PUSH THE FRONT OUT OF THE AREA WEDNESDAY NIGHT AND WILL
MOVE COOLER, DRIER AIR INTO SOUTH FLORIDA BY THURSDAY MORNING.
HOWEVER, EVEN THOUGH IT WILL BE A SIGNIFICANT COOL DOWN, IT WILL
NOT BE ENOUGH TO WARRANT ANY HEADLINES. LOWS THURSDAY LOOK TO BE
IN THE MID 40S FOR THE INTERIOR LAKE REGION TO THE UPPER 50S ALONG
THE ATLANTIC COAST. THE GULF COAST LOOKS TO BE IN THE UPPER 40S TO
LOW 50S. HIGHS THURSDAY WILL RANGE FROM THE LOW 60S IN THE LAKE
REGION TO AROUND 70 IN THE MIAMI AREA.
THIS HIGH IS VERY TRANSIENT AND WILL BE GONE BY THE WEEKEND. THIS
WILL ALLOW TEMPERATURES TO QUICKLY REBOUND AND COASTAL SHOWERS TO
MAKE A RETURN POSSIBLY BY FRIDAY. THE FLOW WILL CONTINUE TO BE
EASTERLY, SO THE ATLANTIC COAST LOOKS TO HAVE THE BEST CHANCE FOR
SHOWER ACTIVITY. BY THE END OF THE WEEKEND, SOUTH FLORIDA WILL BE
BACK UNDER THE WESTERN EDGE OF AN UPPER LEVEL RIDGE AND STILL IN
EASTERLY SFC FLOW. MODELS ARE SHOWING A CHANCE FOR SHOWERS ACROSS
THE AREA BY SUNDAY.
AVIATION...
ALTHOUGH THE RECENT COMPUTER MODEL GUIDANCE DOES NOT INDICATE
MUCH IN THE WAY OF IFR VISIBILITY OR CEILING RESTRICTIONS OR MUCH
POTENTIAL FOR WIDESPREAD FOG DEVELOPMENT THIS MORNING...CONDITIONS
COULD BE FAVORABLE FOR LOW STRATUS AND/OR AREAS OF FOG AS A COLD
FRONT CONTINUES TO MOVE INTO NORTHERN FLORIDA. ALL TAF SITES HAVE
BEEN ASSIGNED PERIODS OF MVFR VISIBILITY RESTRICTIONS FROM 09Z TO
12Z THIS MORNING. BRIEF PERIODS OF NEAR IFR CONDITIONS MAY BE
POSSIBLE AND WILL HAVE TO AMEND IF/WHEN CONDITIONS WARRANT.
REGIONAL WINDS ARE EXPECTED TO BE LIGHT AND SOMEWHAT VARIABLE AT
TIMES.
MARINE...
SHOWER ACTIVITY WILL BE POSSIBLE TODAY AS A COLD FRONT SLOWLY
MOVES THROUGH THE AREA. WINDS WILL SLOWLY TURN TO THE NORTH AND
NORTHEAST TODAY. THERE IS A SLIGHT CHANCE OF A WATERSPOUT, MAINLY
ALONG A CONVERGENCE LINE ALONG THE ATLANTIC COAST THIS MORNING.
THE FRONT WILL STALL JUST TO THE SOUTH, KEEP A SLIGHT CHANCE OF
SHOWERS THROUGH WEDNESDAY. WEDNESDAY NIGHT, A STRONG HIGH WILL
BUILD IN, BRINGING BREEZY CONDITIONS AND BUILDING SEAS FOR THE
END OF THE WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 70 80 67 77 / 20 20 20 10
FORT LAUDERDALE 72 80 69 78 / 20 20 10 10
MIAMI 71 82 69 79 / 20 10 10 10
NAPLES 65 81 64 75 / 10 10 10 10
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...13/SI
LONG TERM....13/SI
AVIATION...21/KM
AREA FORECAST DISCUSSION
NWS MIAMI FL
953 AM EST MON JAN 5 2015
.UPDATE...
CURRENT ANALYSIS SHOWS DEEP LAYER RIDGE STRETCHING ACROSS THE
EXTREME SOUTHERN PORTION OF THE PENINSULA WITH A WEAK COLD FRONT
NEAR THE SOUTHERN SHORES OF LAKE OKEECHOBEE INCLUDING EXTREME
NORTHERN PALM BEACH AND HENDRY COUNTIES ALONG WITH GLADES COUNTY.
THE FRONT IS VERY SHALLOW AND IS MARKED BY A NEAR SOLID DECK OF
LOW STRATUS BEHIND THE LEADING EDGE OF THE BOUNDARY. THE FRONT
WILL NOT MAKE FURTHER PROGRESS SOUTHWARD STALLING NEAR ITS CURRENT
POSITION AND THEN BECOMING DIFFUSE AS THE MAIN UPPER TROUGH LIFTS
WELL TO THE NORTHEAST. THIS WILL LEAVE MOST OF SOUTH FLORIDA IN
THE WARM SECTOR THIS AFTERNOON AND WITH DEW POINTS IN THE UPPER
60S TO AROUND 70, HIGH RESOLUTION SHORT TERM MODEL GUIDANCE
SUGGEST A FEW SHOWERS OVER THE INTERIOR AND EAST COASTAL ZONES.
THE 12Z MFL SOUNDING ALSO SHOWS THE LOW LEVEL MOISTURE INCREASING
FROM YESTERDAY BUT THE STRONG SUBSIDENCE CAP WITH ITS BASE AT 7-8K
WILL KEEP THE SHOWERS LOW TOPPED.
KOB
&&
.PREV DISCUSSION... /ISSUED 624 AM EST MON JAN 5 2015/
AVIATION...
LIGHT TO MODERATE SHOWERS CONTINUE IN THE VICINITY OF ALL THE
ATLANTIC COAST TERMINALS AROUND 11Z AND ARE NEARLY STATIONARY.
BRIEF PERIODS OF NEAR MVFR CEILINGS ARE POSSIBLE THROUGH ABOUT
13Z AS THE SHOWERS ARE NEARLY STATIONARY. OTHERWISE...MAINLY VFR
CONDITIONS EXPECTED LATER THIS MORNING AND THIS AFTERNOON. WINDS
THIS MORNING ARE EXPECTED TO BE LIGHT AND VARIABLE WITH
NORTHEASTERLY WINDS BUILDING INTO THE REGION AROUND 18Z AHEAD OF A
COLD FRONT IN NORTH CENTRAL FLORIDA.
PREV DISCUSSION... /ISSUED 404 AM EST MON JAN 5 2015/
DISCUSSION...
A COLD FRONT IS CURRENTLY MAKING ITS WAY TOWARDS SOUTH FLORIDA AS
EXPECTED. IT IS CURRENTLY IN CENTRAL FLORIDA. AHEAD OF IT SOME
SHOWER ACTIVITY HAS ALREADY DEVELOPED, MAINLY ALONG THE ATLANTIC
COASTLINE. THE HRRR DOES SHOW THIS ACTIVITY ENDING OVER THE NEXT
COUPLE OF HOURS. SO, CONTINUE WITH SLIGHT CHANCE POPS OVER COASTAL
PALM BEACH COUNTY TO COVER ANY SHOWER ACTIVITY THAT PERSISTS.
ANOTHER CONCERN WITH THIS LINE OF CONVERGENCE ALONG THE COAST IS
WATERSPOUT ACTIVITY. ALTHOUGH THE BOUNDARY IS NOT PROMINENT ON
THE GULF COAST, CAN NOT RULE ONE OUT ACROSS ANY OF THE SOUTH
FLORIDA WATERS THIS MORNING.
COMPARING LAST NIGHTS SOUNDING AND THE WATER VAPOR IMAGERY, THE
MOISTURE LOOKS TO BE FAIRLY SHALLOW. THE SOUNDING SHOWS A STRONG
CAP IS IN PLACE AT AROUND 800MB. NAM MODEL SOUNDINGS SHOW IT
SHOULD HOLD, EVEN WITH THE FRONT APPROACHING. THE WATER VAPOR
IMAGERY IS SHOWING THAT THE MOISTURE IS REMAINING MAINLY OVER
NORTH FLORIDA AND SOUTH GEORGIA, WITH LITTLE PROGRESSION TO THE
SOUTH. SO, THIS WILL LEND CREDENCE TO THE LOW POPS THE MODELS ARE
FORECASTING FOR TODAY, WITH A LOW END CHANCE OVER THE A PORTION OF
THE CWA THIS AFTERNOON.
THE FRONT WILL SLOWLY PROGRESS TO THE SOUTH, THROUGH THE CWA
TODAY, AS THE MAIN LOW IS WELL AWAY FROM THE AREA, NORTHEAST OF
MAINE, AND PULLING AWAY. MODELS SHOW THE FRONT WILL MAKE IT
THROUGH MOST OF SOUTH FLORIDA AND PERHAPS TO THE KEYS BEFORE
STALLING OUT. IT WILL THEN REMAIN THROUGH WEDNESDAY AS A WEAK
BOUNDARY, KEEPING A SLIGHT CHANCE OF SHOWERS IN THE FORECAST FOR
PORTIONS OF THE CWA UNTIL WEDNESDAY EVENING. EVEN THAT WILL BE
MORE OR LESS ALONG THE ATLANTIC COAST AND OVER THE ATLANTIC
WATERS. HIGH PRESSURE WILL BUILD IN OVER THE SOUTH EASTERN US, BUT
NEVER DIG FAR ENOUGH SOUTH TO PUSH THE FRONT AWAY FROM THE AREA.
MEANWHILE, ANOTHER LOW WILL MOVE OUT OF THE ROCKIES TODAY AND
QUICKLY MOVE INTO THE PLAINS. MODELS INDICATE IT SHOULD BE OVER
THE MISSISSIPPI VALLEY TONIGHT AND THEN APPEAR TO WASH OUT AS IT
MOVES ACROSS THE APPALACHIANS. MODELS SHOW IT WILL REFORM OFF THE
MID ATLANTIC COAST TUESDAY NIGHT AND BEGIN TO INTERACT WITH THE
STALLED BOUNDARY. AS IT DOES, AS VERY STRONG HIGH WILL MOVE OUT OF
WESTERN CANADA AND INTO THE PLAINS. THIS HIGH WILL WORK WITH THE
LOW TO PUSH THE FRONT OUT OF THE AREA WEDNESDAY NIGHT AND WILL
MOVE COOLER, DRIER AIR INTO SOUTH FLORIDA BY THURSDAY MORNING.
HOWEVER, EVEN THOUGH IT WILL BE A SIGNIFICANT COOL DOWN, IT WILL
NOT BE ENOUGH TO WARRANT ANY HEADLINES. LOWS THURSDAY LOOK TO BE
IN THE MID 40S FOR THE INTERIOR LAKE REGION TO THE UPPER 50S ALONG
THE ATLANTIC COAST. THE GULF COAST LOOKS TO BE IN THE UPPER 40S TO
LOW 50S. HIGHS THURSDAY WILL RANGE FROM THE LOW 60S IN THE LAKE
REGION TO AROUND 70 IN THE MIAMI AREA.
THIS HIGH IS VERY TRANSIENT AND WILL BE GONE BY THE WEEKEND. THIS
WILL ALLOW TEMPERATURES TO QUICKLY REBOUND AND COASTAL SHOWERS TO
MAKE A RETURN POSSIBLY BY FRIDAY. THE FLOW WILL CONTINUE TO BE
EASTERLY, SO THE ATLANTIC COAST LOOKS TO HAVE THE BEST CHANCE FOR
SHOWER ACTIVITY. BY THE END OF THE WEEKEND, SOUTH FLORIDA WILL BE
BACK UNDER THE WESTERN EDGE OF AN UPPER LEVEL RIDGE AND STILL IN
EASTERLY SFC FLOW. MODELS ARE SHOWING A CHANCE FOR SHOWERS ACROSS
THE AREA BY SUNDAY.
AVIATION...
ALTHOUGH THE RECENT COMPUTER MODEL GUIDANCE DOES NOT INDICATE
MUCH IN THE WAY OF IFR VISIBILITY OR CEILING RESTRICTIONS OR MUCH
POTENTIAL FOR WIDESPREAD FOG DEVELOPMENT THIS MORNING...CONDITIONS
COULD BE FAVORABLE FOR LOW STRATUS AND/OR AREAS OF FOG AS A COLD
FRONT CONTINUES TO MOVE INTO NORTHERN FLORIDA. ALL TAF SITES HAVE
BEEN ASSIGNED PERIODS OF MVFR VISIBILITY RESTRICTIONS FROM 09Z TO
12Z THIS MORNING. BRIEF PERIODS OF NEAR IFR CONDITIONS MAY BE
POSSIBLE AND WILL HAVE TO AMEND IF/WHEN CONDITIONS WARRANT.
REGIONAL WINDS ARE EXPECTED TO BE LIGHT AND SOMEWHAT VARIABLE AT
TIMES.
MARINE...
SHOWER ACTIVITY WILL BE POSSIBLE TODAY AS A COLD FRONT SLOWLY
MOVES THROUGH THE AREA. WINDS WILL SLOWLY TURN TO THE NORTH AND
NORTHEAST TODAY. THERE IS A SLIGHT CHANCE OF A WATERSPOUT, MAINLY
ALONG A CONVERGENCE LINE ALONG THE ATLANTIC COAST THIS MORNING.
THE FRONT WILL STALL JUST TO THE SOUTH, KEEP A SLIGHT CHANCE OF
SHOWERS THROUGH WEDNESDAY. WEDNESDAY NIGHT, A STRONG HIGH WILL
BUILD IN, BRINGING BREEZY CONDITIONS AND BUILDING SEAS FOR THE
END OF THE WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 80 70 80 67 / 30 20 20 20
FORT LAUDERDALE 81 72 80 69 / 30 20 20 10
MIAMI 82 71 82 69 / 30 20 10 10
NAPLES 80 65 81 64 / 10 10 10 10
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MIAMI FL
624 AM EST MON JAN 5 2015
.AVIATION...
LIGHT TO MODERATE SHOWERS CONTINUE IN THE VICINITY OF ALL THE
ATLANTIC COAST TERMINALS AROUND 11Z AND ARE NEARLY STATIONARY.
BRIEF PERIODS OF NEAR MVFR CEILINGS ARE POSSIBLE THROUGH ABOUT
13Z AS THE SHOWERS ARE NEARLY STATIONARY. OTHERWISE...MAINLY VFR
CONDITIONS EXPECTED LATER THIS MORNING AND THIS AFTERNOON. WINDS
THIS MORNING ARE EXPECTED TO BE LIGHT AND VARIABLE WITH
NORTHEASTERLY WINDS BUILDING INTO THE REGION AROUND 18Z AHEAD OF A
COLD FRONT IN NORTH CENTRAL FLORIDA.
&&
.PREV DISCUSSION... /ISSUED 404 AM EST MON JAN 5 2015/
DISCUSSION...
A COLD FRONT IS CURRENTLY MAKING ITS WAY TOWARDS SOUTH FLORIDA AS
EXPECTED. IT IS CURRENTLY IN CENTRAL FLORIDA. AHEAD OF IT SOME
SHOWER ACTIVITY HAS ALREADY DEVELOPED, MAINLY ALONG THE ATLANTIC
COASTLINE. THE HRRR DOES SHOW THIS ACTIVITY ENDING OVER THE NEXT
COUPLE OF HOURS. SO, CONTINUE WITH SLIGHT CHANCE POPS OVER COASTAL
PALM BEACH COUNTY TO COVER ANY SHOWER ACTIVITY THAT PERSISTS.
ANOTHER CONCERN WITH THIS LINE OF CONVERGENCE ALONG THE COAST IS
WATERSPOUT ACTIVITY. ALTHOUGH THE BOUNDARY IS NOT PROMINENT ON
THE GULF COAST, CAN NOT RULE ONE OUT ACROSS ANY OF THE SOUTH
FLORIDA WATERS THIS MORNING.
COMPARING LAST NIGHTS SOUNDING AND THE WATER VAPOR IMAGERY, THE
MOISTURE LOOKS TO BE FAIRLY SHALLOW. THE SOUNDING SHOWS A STRONG
CAP IS IN PLACE AT AROUND 800MB. NAM MODEL SOUNDINGS SHOW IT
SHOULD HOLD, EVEN WITH THE FRONT APPROACHING. THE WATER VAPOR
IMAGERY IS SHOWING THAT THE MOISTURE IS REMAINING MAINLY OVER
NORTH FLORIDA AND SOUTH GEORGIA, WITH LITTLE PROGRESSION TO THE
SOUTH. SO, THIS WILL LEND CREDENCE TO THE LOW POPS THE MODELS ARE
FORECASTING FOR TODAY, WITH A LOW END CHANCE OVER THE A PORTION OF
THE CWA THIS AFTERNOON.
THE FRONT WILL SLOWLY PROGRESS TO THE SOUTH, THROUGH THE CWA
TODAY, AS THE MAIN LOW IS WELL AWAY FROM THE AREA, NORTHEAST OF
MAINE, AND PULLING AWAY. MODELS SHOW THE FRONT WILL MAKE IT
THROUGH MOST OF SOUTH FLORIDA AND PERHAPS TO THE KEYS BEFORE
STALLING OUT. IT WILL THEN REMAIN THROUGH WEDNESDAY AS A WEAK
BOUNDARY, KEEPING A SLIGHT CHANCE OF SHOWERS IN THE FORECAST FOR
PORTIONS OF THE CWA UNTIL WEDNESDAY EVENING. EVEN THAT WILL BE
MORE OR LESS ALONG THE ATLANTIC COAST AND OVER THE ATLANTIC
WATERS. HIGH PRESSURE WILL BUILD IN OVER THE SOUTH EASTERN US, BUT
NEVER DIG FAR ENOUGH SOUTH TO PUSH THE FRONT AWAY FROM THE AREA.
MEANWHILE, ANOTHER LOW WILL MOVE OUT OF THE ROCKIES TODAY AND
QUICKLY MOVE INTO THE PLAINS. MODELS INDICATE IT SHOULD BE OVER
THE MISSISSIPPI VALLEY TONIGHT AND THEN APPEAR TO WASH OUT AS IT
MOVES ACROSS THE APPALACHIANS. MODELS SHOW IT WILL REFORM OFF THE
MID ATLANTIC COAST TUESDAY NIGHT AND BEGIN TO INTERACT WITH THE
STALLED BOUNDARY. AS IT DOES, AS VERY STRONG HIGH WILL MOVE OUT OF
WESTERN CANADA AND INTO THE PLAINS. THIS HIGH WILL WORK WITH THE
LOW TO PUSH THE FRONT OUT OF THE AREA WEDNESDAY NIGHT AND WILL
MOVE COOLER, DRIER AIR INTO SOUTH FLORIDA BY THURSDAY MORNING.
HOWEVER, EVEN THOUGH IT WILL BE A SIGNIFICANT COOL DOWN, IT WILL
NOT BE ENOUGH TO WARRANT ANY HEADLINES. LOWS THURSDAY LOOK TO BE
IN THE MID 40S FOR THE INTERIOR LAKE REGION TO THE UPPER 50S ALONG
THE ATLANTIC COAST. THE GULF COAST LOOKS TO BE IN THE UPPER 40S TO
LOW 50S. HIGHS THURSDAY WILL RANGE FROM THE LOW 60S IN THE LAKE
REGION TO AROUND 70 IN THE MIAMI AREA.
THIS HIGH IS VERY TRANSIENT AND WILL BE GONE BY THE WEEKEND. THIS
WILL ALLOW TEMPERATURES TO QUICKLY REBOUND AND COASTAL SHOWERS TO
MAKE A RETURN POSSIBLY BY FRIDAY. THE FLOW WILL CONTINUE TO BE
EASTERLY, SO THE ATLANTIC COAST LOOKS TO HAVE THE BEST CHANCE FOR
SHOWER ACTIVITY. BY THE END OF THE WEEKEND, SOUTH FLORIDA WILL BE
BACK UNDER THE WESTERN EDGE OF AN UPPER LEVEL RIDGE AND STILL IN
EASTERLY SFC FLOW. MODELS ARE SHOWING A CHANCE FOR SHOWERS ACROSS
THE AREA BY SUNDAY.
AVIATION...
ALTHOUGH THE RECENT COMPUTER MODEL GUIDANCE DOES NOT INDICATE
MUCH IN THE WAY OF IFR VISIBILITY OR CEILING RESTRICTIONS OR MUCH
POTENTIAL FOR WIDESPREAD FOG DEVELOPMENT THIS MORNING...CONDITIONS
COULD BE FAVORABLE FOR LOW STRATUS AND/OR AREAS OF FOG AS A COLD
FRONT CONTINUES TO MOVE INTO NORTHERN FLORIDA. ALL TAF SITES HAVE
BEEN ASSIGNED PERIODS OF MVFR VISIBILITY RESTRICTIONS FROM 09Z TO
12Z THIS MORNING. BRIEF PERIODS OF NEAR IFR CONDITIONS MAY BE
POSSIBLE AND WILL HAVE TO AMEND IF/WHEN CONDITIONS WARRANT.
REGIONAL WINDS ARE EXPECTED TO BE LIGHT AND SOMEWHAT VARIABLE AT
TIMES.
MARINE...
SHOWER ACTIVITY WILL BE POSSIBLE TODAY AS A COLD FRONT SLOWLY
MOVES THROUGH THE AREA. WINDS WILL SLOWLY TURN TO THE NORTH AND
NORTHEAST TODAY. THERE IS A SLIGHT CHANCE OF A WATERSPOUT, MAINLY
ALONG A CONVERGENCE LINE ALONG THE ATLANTIC COAST THIS MORNING.
THE FRONT WILL STALL JUST TO THE SOUTH, KEEP A SLIGHT CHANCE OF
SHOWERS THROUGH WEDNESDAY. WEDNESDAY NIGHT, A STRONG HIGH WILL
BUILD IN, BRINGING BREEZY CONDITIONS AND BUILDING SEAS FOR THE
END OF THE WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 80 70 80 67 / 30 20 20 20
FORT LAUDERDALE 81 72 80 69 / 20 20 20 10
MIAMI 82 71 82 69 / 20 20 10 10
NAPLES 80 65 81 64 / 10 10 10 10
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...13/SI
LONG TERM....13/SI
AVIATION...60/BD
AREA FORECAST DISCUSSION
NWS MIAMI FL
404 AM EST MON JAN 5 2015
.DISCUSSION...
A COLD FRONT IS CURRENTLY MAKING ITS WAY TOWARDS SOUTH FLORIDA AS
EXPECTED. IT IS CURRENTLY IN CENTRAL FLORIDA. AHEAD OF IT SOME
SHOWER ACTIVITY HAS ALREADY DEVELOPED, MAINLY ALONG THE ATLANTIC
COASTLINE. THE HRRR DOES SHOW THIS ACTIVITY ENDING OVER THE NEXT
COUPLE OF HOURS. SO, CONTINUE WITH SLIGHT CHANCE POPS OVER COASTAL
PALM BEACH COUNTY TO COVER ANY SHOWER ACTIVITY THAT PERSISTS.
ANOTHER CONCERN WITH THIS LINE OF CONVERGENCE ALONG THE COAST IS
WATERSPOUT ACTIVITY. ALTHOUGH THE BOUNDARY IS NOT PROMINENT ON
THE GULF COAST, CAN NOT RULE ONE OUT ACROSS ANY OF THE SOUTH
FLORIDA WATERS THIS MORNING.
COMPARING LAST NIGHTS SOUNDING AND THE WATER VAPOR IMAGERY, THE
MOISTURE LOOKS TO BE FAIRLY SHALLOW. THE SOUNDING SHOWS A STRONG
CAP IS IN PLACE AT AROUND 800MB. NAM MODEL SOUNDINGS SHOW IT
SHOULD HOLD, EVEN WITH THE FRONT APPROACHING. THE WATER VAPOR
IMAGERY IS SHOWING THAT THE MOISTURE IS REMAINING MAINLY OVER
NORTH FLORIDA AND SOUTH GEORGIA, WITH LITTLE PROGRESSION TO THE
SOUTH. SO, THIS WILL LEND CREDENCE TO THE LOW POPS THE MODELS ARE
FORECASTING FOR TODAY, WITH A LOW END CHANCE OVER THE A PORTION OF
THE CWA THIS AFTERNOON.
THE FRONT WILL SLOWLY PROGRESS TO THE SOUTH, THROUGH THE CWA
TODAY, AS THE MAIN LOW IS WELL AWAY FROM THE AREA, NORTHEAST OF
MAINE, AND PULLING AWAY. MODELS SHOW THE FRONT WILL MAKE IT
THROUGH MOST OF SOUTH FLORIDA AND PERHAPS TO THE KEYS BEFORE
STALLING OUT. IT WILL THEN SIT FOR THROUGH WEDNESDAY AS A WEAK
BOUNDARY, KEEPING A SLIGHT CHANCE OF SHOWERS IN THE FORECAST FOR
PORTIONS OF THE CWA UNTIL WEDNESDAY EVENING. EVEN THAT WILL BE
MORE OR LESS ALONG THE ATLANTIC COAST AND OVER THE ATLANTIC
WATERS. HIGH PRESSURE WILL BUILD IN OVER THE SOUTH EASTERN US, BUT
NEVER DIG FAR ENOUGH SOUTH TO PUSH THE FRONT AWAY FROM THE AREA.
MEANWHILE, ANOTHER LOW WILL MOVE OUT OF THE ROCKIES TODAY AND
QUICKLY MOVE INTO THE PLAINS. MODELS INDICATE IT SHOULD BE OVER
THE MISSISSIPPI VALLEY TONIGHT AND THEN APPEAR TO WASH OUT AS IT
MOVES ACROSS THE APPALACIANS. MODELS SHOW IT WILL REFORM OFF THE
MID ATLANTIC COAST TUESDAY NIGHT AND BEGIN TO INTERACT WITH THE
STALLED BOUNDARY. AS IT DOES, AS VERY STRONG HIGH WILL MOVE OUT OF
WESTERN CANADA AND INTO THE PLAINS. THIS HIGH WILL WORK WITH THE
LOW TO PUSH THE FRONT OUT OF THE AREA WEDNESDAY NIGHT AND WILL
MOVE COOLER, DRIER AIR INTO SOUTH FLORIDA BY THURSDAY MORNING.
HOWEVER, EVEN THOUGH IT WILL BE A SIGNIFICANT COOL DOWN. IT WILL
NOT BE ENOUGH TO WARRANT ANY HEADLINES. LOWS THURSDAY LOOK TO BE
IN THE MID 40S FOR THE INTERIOR LAKE REGION TO THE UPPER 50S ALONG
THE ATLANTIC COAST. THE GULF COAST LOOKS TO BE IN THE UPPER 40S TO
LOW 50S. HIGHS THURSDAY WILL RANGE FROM THE LOW 60S IN THE LAKE
REGION TO AROUND 70 IN THE MIAMI AREA.
THIS HIGH IS VERY TRANSIENT AND WILL BE GONE BY THE WEEKEND. THIS
WILL ALLOW TEMPERATURES TO QUICKLY REBOUND AND COASTAL SHOWERS TO
MAKE A RETURN POSSIBLY BY FRIDAY. THE FLOW WILL CONTINUE TO BE
EASTERLY, SO THE ATLANTIC COAST LOOKS TO HAVE THE BEST CHANCE FOR
SHOWER ACTIVITY. BY THE END OF THE WEEKEND, SOUTH FLORIDA WILL BE
BACK UNDER THE WESTERN EDGE OF AN UPPER LEVEL RIDGE AND STILL IN
EASTERLY SFC FLOW. MODELS ARE SHOWING A CHANCE FOR SHOWERS ACROSS
THE AREA BY SUNDAY.
&&
.AVIATION...
ALTHOUGH THE RECENT COMPUTER MODEL GUIDANCE DOES NOT INDICATE
MUCH IN THE WAY OF IFR VISIBILITY OR CEILING RESTRICTIONS OR MUCH
POTENTIAL FOR WIDESPREAD FOG DEVELOPMENT THIS MORNING...CONDITIONS
COULD BE FAVORABLE FOR LOW STRATUS AND/OR AREAS OF FOG AS A COLD
FRONT CONTINUES TO MOVE INTO NORTHERN FLORIDA. ALL TAF SITES HAVE
BEEN ASSIGNED PERIODS OF MVFR VISIBILITY RESTRICTIONS FROM 09Z TO
12Z THIS MORNING. BRIEF PERIODS OF NEAR IFR CONDITIONS MAY BE
POSSIBLE AND WILL HAVE TO AMEND IF/WHEN CONDITIONS WARRANT.
REGIONAL WINDS ARE EXPECTED TO BE LIGHT AND SOMEWHAT VARIABLE AT
TIMES.
&&
.MARINE...
SHOWER ACTIVITY WILL BE POSSIBLE TODAY AS A COLD FRONT SLOWLY
MOVES THROUGH THE AREA. WINDS WILL SLOWLY TURN TO THE NORTH AND
NORTHEAST TODAY. THERE IS A SLIGHT CHANCE OF A WATERSPOUT, MAINLY
ALONG A CONVERGENCE LINE ALONG THE ATLANTIC COAST THIS MORNING.
THE FRONT WILL STALL JUST TO THE SOUTH, KEEP A SLIGHT CHANCE OF
SHOWERS THROUGH WEDNESDAY. WEDNESDAY NIGHT, A STRONG HIGH WILL
BUILD IN, BRINGING BREEZY CONDITIONS AND BUILDING SEAS FOR THE
END OF THE WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 80 70 80 67 / 30 20 20 20
FORT LAUDERDALE 81 72 80 69 / 20 20 20 10
MIAMI 82 71 82 69 / 20 20 10 10
NAPLES 80 65 81 64 / 10 10 10 10
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...13/SI
LONG TERM....13/SI
AVIATION...60/BD
AREA FORECAST DISCUSSION
NWS MIAMI FL
1247 AM EST MON JAN 5 2015
.AVIATION...
ALTHOUGH THE RECENT COMPUTER MODEL GUIDANCE DOES NOT INDICATE
MUCH IN THE WAY OF IFR VISIBILITY OR CEILING RESTRICTIONS OR MUCH
POTENTIAL FOR WIDESPREAD FOG DEVELOPMENT THIS MORNING...CONDITIONS
COULD BE FAVORABLE FOR LOW STRATUS AND/OR AREAS OF FOG AS A COLD
FRONT CONTINUES TO MOVE INTO NORTHERN FLORIDA. ALL TAF SITES HAVE
BEEN ASSIGNED PERIODS OF MVFR VISIBILITY RESTRICTIONS FROM 09Z TO
12Z THIS MORNING. BRIEF PERIODS OF NEAR IFR CONDITIONS MAY BE
POSSIBLE AND WILL HAVE TO AMEND IF/WHEN CONDITIONS WARRANT.
REGIONAL WINDS ARE EXPECTED TO BE LIGHT AND SOMEWHAT VARIABLE AT
TIMES.
60
&&
.PREV DISCUSSION... /ISSUED 721 PM EST SUN JAN 4 2015/
UPDATE...IT SURE DOESN`T FEEL LIKE JANUARY! A DEWPOINT OF 72F AT
THE OFFICE RIGHT NOW. THIS RATHER STEAMY AIRMASS ALONG WITH JUST
SLIGHT CONVERGENCE IN SURFACE WINDS (SE WINDS ENCOUNTERING SW
WINDS IN THE LAKE REGION) HAS ALLOWED FOR A BROKEN BAND OF
MODERATE TO HEAVY SHOWERS TO DEVELOP FROM SOUTHEASTERN HENDRY
COUNTY EXTENDING NORTHEAST TO LAKE OKEECHOBEE.THE LATEST RUN OF
THE HRRR INITIALIZED WELL, DEPICTING SHOWER ACTIVITY ACROSS THIS
REGION AND SHOWS THESE SHOWERS DECAYING THROUGH MIDNIGHT. THIS
SEEMS REASONABLE WITH THE LOSS OF DAYTIME HEATING. SO THE ONLY
UPDATE TO THE FORECAST WAS TO ADD THE ONGOING ISOLATED SHOWERS
ACROSS THIS REGION FOR THE NEXT FEW HOURS. /GREGORIA
PREV DISCUSSION... /ISSUED 654 PM EST SUN JAN 4 2015/
AVIATION...
MAINLY VFR CONDITIONS TO PREVAIL THROUGH THE PERIOD. MAINLY LIGHT
SOUTHERLY WINDS WILL TRANSITION EAST-SOUTHEASTERLY THROUGH THE
NIGHT AS A COLD FRONT APPROACHES THE AREA FROM THE NORTH. FRONT
SHOULD EASE INTO SOUTH FLORIDA TOWARD THE LAST FEW HOURS OF THIS
TAF CYCLE TURNING WINDS AROUND TO THE NORTHEAST. A FEW SHOWERS MAY
BRIEFLY AFFECT THE TAF SITES AS THE FRONT APPROACHES BUT COVERAGE
SHOULD BE TOO SPARSE TO MENTION IN TAFS FOR NOW. MAIN CONCERN FOR
FOG DEVELOPMENT WILL BE ACROSS THE NORTHWEST INTERIOR AND MAY
BRIEFLY AFFECT KAPF. PLACED A TEMPO FOR MVFR VSBY FROM 09Z-13Z AS
IT LOOKS LIKE BEST COVERAGE FOR FOG WILL REMAIN EAST OF KAPF.
PREV DISCUSSION... /ISSUED 249 PM EST SUN JAN 4 2015/
SHORT TERM (TONIGHT THROUGH WEDNESDAY)...
LARGE AND DEEP-LAYERED SUBTROPICAL HIGH PRESSURE EXTENDING FROM
THE BAHAMAS ACROSS SOUTH FLORIDA WILL PERSIST THROUGH TUESDAY,
THEN FINALLY GIVE WAY TO AMPLIFYING EASTERN U.S. TROUGH BY
WEDNESDAY. THE RIDGE WILL KEEP THE STRONG/SEVERE TSTMS CURRENTLY
OVER THE FLORIDA PANHANDLE FROM REACHING OUR PART OF THE STATE.
THE COLD FRONT ASSOCIATED WITH THESE TSTMS WILL MOVE DOWN THE
STATE TONIGHT, REACHING THE LAKE OKEECHOBEE AREA SHORTLY AFTER
SUNRISE MONDAY. AHEAD OF THE FRONT, A FEW LIGHT SHOWERS (SIMILAR
TO WHAT WE`RE SEEING THIS AFTERNOON) ARE NOT TOTALLY OUT OF THE
QUESTION BUT NOT HIGH ENOUGH PROBABILITY (10%) TO INCLUDE IN
FORECAST. AS IS TYPICAL WITH NIGHTTIME FRONTS NORTH OF LAKE
OKEECHOBEE, PATCHY FOG IS EXPECTED AND COULD BE DENSE IN A FEW
AREAS OF THE INTERIOR AND WEST. SHORT RANGE ENSEMBLE FORECASTS ARE
NOT SHOWING HIGH PROBABILITIES OF DENSE FOG, BUT FEEL THIS IS
UNDERDONE AND WE MAY END UP WITH AREAS OF FOG OVER THE EVERGLADES.
THIS IS WHAT WE`LL DEPICT FOR TONIGHT.
THE FRONT WILL MOVE INTO SOUTH FLORIDA ON MONDAY, BUT LIKELY STALL
OVER THE EXTREME SOUTHERN PORTION OF THE AREA BY MONDAY NIGHT AS
THE STRONG RIDGE HELPS TO PUT THE BRAKES ON ANY SOUTHWARD PROGRESS
OF THE FRONT. ONLY SLIGHT COOLING BEHIND THE FRONT (NEAR 80
INSTEAD OF MID 80S PALM BEACHES AND LAKE AREA) WITH NE WINDS
PROVIDING A SLIGHT CHANCE OF SHOWERS EASTERN METRO AREAS. FRONT
WILL BE DIFFUSE ON TUESDAY BUT ENOUGH LINGERING MOISTURE TO KEEP
IN A PESKY 20/30% CHANCE OF SHOWERS AREA-WIDE. ONLY A COUPLE OF
DEGREES COOLER FOR HIGH TEMPERATURES, BUT STILL AROUND 80 TO THE
LOWER 80S ON TUESDAY.
BY WEDNESDAY, THINGS BEGIN TO CHANGE AS A STRONGER FRONT MOVES
DOWN THE PENINSULA IN RESPONSE TO A DEEPENING EASTERN U.S. TROUGH.
MODELS NOT SHOWING MUCH IN THE WAY OF LOW-LEVEL CONVERGENCE AHEAD
OF THIS NEXT FRONT, THEREFORE SHOWER CHANCES WILL REMAIN ON THE
LOW SIDE (LESS THAN 20%) DURING THE DAY ON WEDNESDAY AS HIGH TEMPS
STILL MANAGE TO REACH THE MID 70S TO AROUND 80.
LONG TERM (WEDNESDAY NIGHT THROUGH SUNDAY)...
THE FRONT WILL MOVE THROUGH SOUTH FLORIDA WEDNESDAY NIGHT,
USHERING IN MUCH COOLER (BUT NOT UNSEASONABLY COLD) AIR. AIR MASS
BEHIND THIS FRONT IS PLENTY COLD, BUT GLOBAL MODELS AGREE IN
SHOWING THE ARCTIC HIGH PRESSURE CENTER BEHIND THE FRONT TO SLIDE
MORE EAST THAN SOUTH, GIVING SOUTH FLORIDA MORE OF A GLANCING BLOW
THAN A STRAIGHT SHOT OF COLD AIR. CONSENSUS OF MODEL SOLUTIONS
(INCLUDING ENSEMBLES) SHOW LOW TEMPERATURES THURSDAY AND FRIDAY
MORNINGS RANGING FROM THE MID 40S WEST OF LAKE OKEECHOBEE TO NEAR
60 EAST COAST, NOT TOO FAR FROM EARLY JANUARY NORMALS). THE
SHALLOW NATURE OF THIS FRONT ALSO MEANS THAT INSTEAD OF THE
TYPICAL CLEARING BEHIND STRONG FRONTS, WE WILL LIKELY SEE AN
EXTENDED PERIOD OF CLOUDS AND SCATTERED SHOWERS, PARTICULARLY
EASTERN METRO AREAS. THIS COULD LEAD TO LOWER MAX TEMPERATURES ON
THURSDAY AND FRIDAY THAN WHAT IS CURRENTLY FORECAST. MODELS SHOW
PLENTY OF MOISTURE HANGING AROUND THROUGH NEXT WEEKEND, SO IT
LOOKS LIKE A RATHER GLOOMY SECOND HALF OF THE WEEK INTO NEXT
WEEKEND FOR SOUTH FLORIDA.
MARINE...
AFTER SOME HIGHER WIND GUSTS TODAY, WINDS DECREASE TONIGHT WITH
SUBSIDING SEAS. A BRIEF SURGE IN NORTHEAST WINDS BEHIND THE FRONT
ON MONDAY AND MONDAY NIGHT, FOLLOWED BY LIGHT E-NE WINDS TUESDAY
INTO WEDNESDAY. THE NEXT FRONT ON WEDNESDAY WILL BE FOLLOWED BY
MUCH STRONGER NORTH WINDS, WITH WINDS NEAR 25 KT LIKELY WITH
HIGHER GUSTS AND ROUGH SEAS LASTING THROUGH THURSDAY.
CLIMATE...
THIS MORNING`S LOW TEMPERATURES AT ALL FOUR MAIN CLIMATE SITES ARE
ON PACE TO EITHER TIE OR BREAK HIGH MINIMUM RECORDS FOR THE DATE:
MIA: AM LOW 76/RECORD 76 (1971)
FLL: AM LOW 75/RECORD 74 (2007)
PBI: AM LOW 76/RECORD 73 (2007)
APF: AM LOW 70/RECORD 68 (1973)
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 80 70 80 67 / 20 20 20 20
FORT LAUDERDALE 81 72 80 69 / 20 20 10 20
MIAMI 82 71 81 69 / 20 20 10 20
NAPLES 80 65 80 65 / 10 10 10 10
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...60/BD
LONG TERM....13/SI
AVIATION...60/BD
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
326 PM CST MON JAN 5 2015
.SHORT TERM...
302 PM CST
TONIGHT...
SYNOPTIC/FORCING DISCUSSION...WATER VAPOR IMAGERY SHOWS THE
APPROACHING UPPER TROUGH QUICKLY MOVING ACROSS THE NORTHERN PLAINS
WITH THE ATTENDANT SFC LOW MOVING ALONG THE CENTRAL SOUTH
DAKOTA/NEBRASKA BORDER. SNOW CONTINUES TO SPREAD EASTWARD ACROSS
IOWA WITH A WARM ADVECTION RIBBON EXTENDING EAST-SOUTHEAST INTO
CENTRAL ILLINOIS. MANY SITES ACROSS IOWA ARE REPORTING 1/4 TO 1/2SM
VSBY WITH STRONG REFLECTIVITY ON THE RADAR MOSAIC. GROUND REPORTS
THUS FAR INDICATE INCH PER HOURS AMOUNTS WITH NEAR 0.10 INCH LIQUID
LEADING TO 10-11:1 SNOW RATIOS. LATEST NEAR TERM GUIDANCE TRENDS
SHOW THAT THE BEST FGEN FORCING WILL TRACK ACROSS THE SOUTHERN THIRD
TO HALF OF THE ARA THIS EVENING CONTINUING TO SUPPORT THE IDEA THAT
THAT IS WHERE THE HEAVIEST SNOW WILL FALL. HEAVIEST LIQUID SHOULD
FALL JUST NORTH OF THE LOW TRACK WHICH WILL BE TO THE SOUTH OF THE
CWA. FORECAST SOUNDINGS CONTINUE TO SHOW A DEEP SNOW GROWTH ZONE BUT
ALIGNMENT OF BEST ASCENT VARIES ACROSS THE AREA. NORTHERN AREAS
ENTRENCHED IN THE DEEPER COLD AIR WILL SEE THE BULK OF THE FORCING
ABOVE THE BEST SNOW GROWTH ZONE WHILE AREAS SOUTH SEE A BETTER
ALIGNMENT. THIS MAY BE WHAT IS OCCURRING ACROSS CENTRAL IOWA WHERE
LOWER RATIOS HAVE BEEN REPORTED THUS FAR /SMALLER FLAKE SIZE AND
LESS FLUFF TO ACCUMULATION/.
ACCUMULATION/TIMING DISCUSSION...WITH SNOW QUICKLY PROGRESSING
EASTWARD HAVE BUMPED UP POPS AFTER 22Z IN THE SOUTHWEST CWA.
SOUTHWEST AREAS WILL LIKELY SEE A QUICK RAMP UP IN INTENSITY BY
AROUND 00Z WITH A 4-5 HOUR WINDOW OF STRONG FORCING BEFORE THINGS
TAPER AROUND AND AFTER 06Z. MOST AREAS WILL SEE A 3-5 HOUR WINDOW
FOR SNOW BEFORE THINGS QUICKLY EXIT TO THE SOUTHEAST OVERNIGHT. WILL
CONTINUE WITH THE EXPECTATION OF 15-18:1 RATIOS FOR NOW. BEST
FORCING...ALIGNMENT OF FORCING WITHIN THE SNOW GROWTH ZONE...AND
DURATION OF FORCING CONTINUE TO BE ALIGNED OVER THE FAR SOUTHERN CWA
WITH THESE ELEMENTS LESS ALIGNED TO THE NORTH. WITH THIS IN MIND HAVE
TIGHTENED UP THE ACCUMULATION GRADIENT ACROSS THE AREA SOMEWHAT TO
SHOW A LITTLE BIT LESS IN FAR NORTHEAST IL. AREAS GENERALLY ALONG
AND SOUTH OF A MENDOTA TO SOUTH CHICAGO METRO TO RENSSELAER LOOK TO
SEE SNOW FALL ACCUMULATION RATES OF AROUND 1 INCH PER HOUR LEADING
TO A BROAD AREA OF 3 TO 6 INCH TOTALS WITH AREAS ALONG A AND SOUTH
OF A STREATOR TO WATSEKA TO FOWLER LINE SEEING THE BEST CHANCE FOR
EVEN 5 TO 7 INCHES.
HEADLINE AND IMPACTS DISCUSSION...WILL CONTINUE WITH THE WINTER
WEATHER ADVISORY FOR THE BULK OF THE AREA GIVEN EXPECTED AMOUNTS.
HAVE MADE AN EARLY UPGRADE TO A WINTER STORM WARNING IN THE FAR
SOUTH GIVEN THE EXPECTED BETTER BANDING AND BETTER ALIGNMENT OF
FORCING ETC. DISCUSSED ABOVE. SNOWFALL INTENSITY/ACCUMULATION RATE
WILL BE THE BIGGEST IMPACT WITH RATES AROUND AN INCH PER HOUR AND
POSSIBLY TOWARDS 1.5 IN/HR IN THE FAR SOUTH MAKING SNOW REMOVAL
DIFFICULT...NOT TO MENTION LIMITING VISIBILITY TO A QUARTER MILE OR
LESS AT TIMES. DESPITE LIGHTER AMOUNTS ACROSS THE NORTHERN CWA STILL
EXPECT A DECENT ACCUMULATION RATE LEADING TO TRAVEL HAZARDS.
MDB
&&
.LONG TERM...
325 PM CST
TUESDAY THROUGH THURSDAY...EXPECT THE SNOW TO BE EAST OF THE AREA BY
TUESDAY MORNING. WINDS WILL SHIFT TO THE NORTH THEN QUICKLY TO THE
WEST. IT IS POSSIBLE THAT SOME LAKE SNOW SHOWERS COULD ORGANIZE
ENOUGH TO IMPACT PORTER COUNTY FOR A VERY SHORT TIME BEFORE DAYBREAK
BUT THEY WOULD QUICKLY END. HIGH PRESSURE WILL BE IN PLACE ACROSS
THE CENTRAL PLAINS BUT A REINFORCING HIGH OVER WESTERN CANADA WILL
QUICKLY MERGE WITH IT INTO WEDNESDAY. BY THIS TIME...A BROAD UPPER
TROUGH WILL BE IN PLACE ACROSS THE EASTERN TWO-THIRDS OF THE CONUS.
ANOTHER TROUGH AXIS WILL BE DROPPING SOUTHWARD TUESDAY EVENING. IT
WILL BE QUITE SHEARED OUT BUT THERE MAY BE ENOUGH LIFT IN THE
INCREASINGLY COLD AIR TO GENERATE SOME FLURRIES.
THE MAIN ISSUE WILL BE EXTREMELY COLD AIR. WITH THE AREA BETWEEN LOW
PRESSURE TO THE EAST AND THE BUILDING HIGH TO THE WEST BREEZY WETS
TO NORTHWEST WINDS WILL DEVELOP LATER TUESDAY AND CONTINUE INTO
WEDNESDAY NIGHT BEFORE DIMINISHING AND SHIFTING SOUTHWEST. THE
INITIAL ISSUE WILL BE BLOWING SNOW AND REDUCED VSBY LEADING TO
HAZARDOUS TRAVEL SO WILL NEED TO ASSESS THE NEED FOR A WINTER
WEATHER ADVISORY FOR THIS LATER TUESDAY INTO AT LEAST WEDNESDAY.
TEMPS WILL FALL TO TO THE SINGLE DIGITS BELOW ZERO TUESDAY NIGHT
WITH LITTLE RECOVERY WEDNESDAY...THEN FALL TO -5 TO -15 OR SO
WEDNESDAY NIGHT. WILL NEED WIND CHILL HEADLINES FROM TUESDAY NIGHT
THROUGH THURSDAY MORNING. AFTER COORDINATION WITH NEIGHBORS WILL
HOLD OFF ON THIS FOR NOW DUE TO THE ARRIVING SNOW EVENT. MOST AREAS
OF ILLINOIS LOOK TO MEET WARNING CRITERIA AND SOUTHERN AREAS AND
NORTHWEST INDIANA MAY BE IN HIGH END ADVISORY CRITERIA. OVERALL
EXPECT WIND CHILLS OF -20 TO AROUND -35 DURING THIS PERIOD WITH
LITTLE IMPROVEMENT DURING THE DAY WEDNESDAY.
THURSDAY THROUGH THE WEEKEND...THE SURFACE HIGH WILL PASS THURSDAY
ALLOWING A SOUTHWESTERLY FLOW TO DEVELOP. THIS WILL COMBINE WITH
ANOTHER APPROACHING SYSTEM FORM THE NORTHWEST WHICH WILL ALLOW FOR
SOME MODEST WARMING...LEADING TO A NOTICEABLE MODERATION OF TEMPS TO
THE TEENS. THE PASSING TROUGH MAY EXTEND FAR ENOUGH SOUTH TO PRODUCE
SOME LIGHT SNOW LATER THURSDAY BUT WILL NEED TO FURTHER EVALUATE
THIS. THINGS COOL SLIGHTLY FOR FRIDAY BUT THE BIG TROUGH LOOKS TO
SHIFT EAST INTO THE WEEKEND. THIS WILL ALLOW FOR MORE OF A ZONAL FLOW
RESULTING IN A MODERATION OF TEMPS. EMBEDDED WAVES MAY BRING SOME
CHANCES FOR PRECIP AS WELL.
MDB
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* ONSET TIMING OF SNOW EARLY THIS EVENING...AND PERIOD OF THE
LOWEST VIS AND CIGS IN SNOW THIS EVENING.
* POTENTIAL FOR A SLIGHTLY EARLIER ONSET OF SNOW EARLY THIS
EVENING.
KJB
//DISCUSSION...UPDATED 18Z...
A QUICK MOVING WEATHER DISTURBANCE WILL SPREAD SNOW ACROSS THE
REGION BY THIS EVENING. THE SNOW WILL LIKELY BE MODERATE TO HEAVY IN
INTENSITY...WITH VISIBILITIES LIKELY FALLING UNDER A MILE WITHIN THE
HEAVIEST SNOW. DUE TO THE FAST MOVEMENT OF THIS SYSTEM...THERE WILL
ONLY BE ABOUT A 6 TO 8 HOUR WINDOW OF SNOWFALL...WITH THE HEAVIEST
SNOW RATES...UP TO AN INCH PER HOUR...OCCURRING DURING A 2 TO 3 HOUR
PERIOD BETWEEN ABOUT 03 AND 05-06 UTC THIS EVENING. WE CURRENTLY
EXPECT THE SNOW TO ONSET AROUND OR JUST AFTER 00 UTC THIS
EVENING AT KRFD...AND AROUND OR SHORTLY AFTER THE 01-02 UTC
TIME FRAME ACROSS THE EASTERN TERMINALS. THE SNOW SHOULD END FROM
WEST TO EAST OVERNIGHT PRIOR TO DAYBREAK TUESDAY. IFR CIGS AND LIFR
VISIBILITIES ARE LIKELY DURING THE PERIOD OF HEAVIEST SNOW...WITH
CONDITIONS RAPIDLY IMPROVING EARLY TUESDAY MORNING. WINDS WILL
REMAIN FAIRLY LIGHT OUT OF THE SOUTHWEST THIS EVENING...THEN BECOME
MORE NORTHWESTERLY BY DAYBREAK TUESDAY.
KJB
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* MEDIUM WITH ONSET TIMING OF SNOW THIS EVENING...WITH A
POSSIBILITY OF A SLIGHTLY EARLIER ONSET.
* MODERATE WITH TIMING OF LOWEST CIGS/VSBYS IN SNOW LATER THIS
EVENING.
KJB
//OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z...
TUESDAY...IMPROVING TO VFR.
WEDNESDAY...VFR.
THURSDAY...PRIMARILY VFR. GUSTY SOUTHWEST WINDS.
FRIDAY...PRIMARILY VFR.
SATURDAY...CHANCE OF SNOW.
SUNDAY...CHANCE OF SNOW EARLY.
BEACHLER
&&
.MARINE...
319 PM CST
THE ROGER BLOUGH WHICH HAS BEEN COMING DOWN THE WISCONSIN SIDE OF
THE LAKE AND IS CROSSING THE SOUTH END HAS BEEN REPORTING WAVES
AROUND 5 FT THIS AFTERNOON. THESE WAVES SHOULD BE SUBSIDING
SLIGHTLY OVERNIGHT AS HIGH PRESSURE MOVES ACROSS THE SOUTH END OF
THE LAKE AND IS FOLLOWED BY A WEAK LOW...ALLOWING WINDS TO
CONTINUE TO DIMINISH FROM EARLIER GALES. WAVES BUILD AGAIN
TOMORROW AS WEST WINDS INCREASE AHEAD OF THE NEXT APPROACHING
HIGH. MORE SUBSTANTIAL WAVE GROWTH OCCURS TUESDAY NIGHT INTO
WEDNESDAY AS THE STRONG HIGH PRESSES INTO THE MIDWEST AND WINDS
INCREASE CONSIDERABLY FROM THE NORTHWEST. HEAVY FREEZING SPRAY
WILL ALSO BE A CONCERN STARTING LATE TUESDAY AND CONTINUING AT
LEAST INTO WEDNESDAY AFTERNOON WITH BITTERLY COLD AIR AND STRONG
NORTHWEST GUSTS.
AFTER THE GALE AND FREEZING SPRAY EVENT TOWARD MIDWEEK...THE
REMAINDER OF THE WEEK BRINGS CONTINUED CHANCES FOR STRONG WINDS AND
HIGH WAVES ON THE LAKE...THOUGH THE AIR WILL NOT BE AS COLD.
LENNING
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...WINTER STORM WARNING...ILZ032-ILZ033-ILZ039 UNTIL 6 AM TUESDAY.
WINTER WEATHER ADVISORY...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-
ILZ010-ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-
ILZ022-ILZ023 UNTIL 6 AM TUESDAY.
IN...WINTER WEATHER ADVISORY...INZ001-INZ002-INZ010-INZ011 UNTIL 6 AM
TUESDAY.
WINTER STORM WARNING...INZ019 UNTIL 6 AM TUESDAY.
LM...GALE WATCH...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ740-LMZ741-LMZ742-
LMZ743-LMZ744-LMZ745-LMZ777-LMZ779-LMZ868-LMZ870-LMZ872-
LMZ874-LMZ876-LMZ878...6 PM TUESDAY TO 3 PM WEDNESDAY.
HEAVY FREEZING SPRAY WATCH...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-
LMZ563-LMZ565-LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ740-
LMZ741-LMZ742-LMZ743-LMZ744-LMZ745-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...6 PM TUESDAY TO 3 PM
WEDNESDAY.
&&
$$
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Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
315 PM CST Mon Jan 5 2015
.SHORT TERM...(Tonight)
ISSUED AT 313 PM CST MON JAN 5 2015
The 12z models continue to show a short duration, high-intensity
snow event this evening. Light snow has already developed across
our SW counties, which the HRRR shows will expand northward by 6
pm and intensify this evening. The surface low track is progged to
go across IL on a line from Pittsfield to Effingham, which
generally fits our current snowfall forecast coverage. One
additional concern is trying to pinpoint the location of the
traditional 60-80 mile wide band of heaviest snowfall. At this
point, it looks like it will extend along and just north of the
I-74 corridor. Satellite and radar images are confirming the
development of a robust frontogenetical circulation upstream
across NE SD, SW MN, and Iowa. Model analysis shows that to be in
the 850-700 mb layer. The strongest axis of this F-gen circ is
projected to advance across our northern counties this evening.
Bufkit sounding analysis for sites along the I-74 corridor
continues to indicate the co- location of the max omega, 80+% RH,
and dendritic growth zone for several hours this evening. Those
conditions will translate to the production of large, fluffy
snowflakes. Snowfall rates in this axis will likely climb between
1-1.5" per hour. Additional small- scale bands of heavier snow
could develop in areas farther south and north of the primary
band, so we kept the snow totals on the higher side of advisory
all the way through Lincoln to Mattoon, where a range of 2-5" is
expected. A sharp southern edge remains indicated by most of the
model suite, with locations south of Springfield and Mattoon
likely seeing a dusting to 1 inch.
In addition, after coordination with DVN, LOT, and IND, we decided to
upgrade the I-74 corridor counties from Advisory to Warning due to
the potential for more widespread 6-7" snowfall totals.
The southeast winds this evening will not be much stronger that 10
mph, but the fluffy snow may be light enough for some minor drifting
along roadways.
Snowfall will rapidly diminish from west to east late this evening
and after midnight, as the clipper races into southern Indiana/
Kentucky and weakens. Additional snow accums after midnight will be
light, with the best chances of more than a half inch mainly east of
Champaign to Paris. Most areas will just see some lingering flurries
for a few hours after midnight.
Low temps tonight will drop into the 5-10 range north, with around
20 from Flora to Lawrenceville.
&&
.LONG TERM...(Tuesday through Monday)
ISSUED AT 313 PM CST MON JAN 5 2015
The bitterly cold airmass will dominate the remainder of the
forecast. Models are still on track with the intense cold that will
follow tonight`s clipper.
Tuesday will see skies begin to clear out from west to east during
the afternoon, and W-NW winds increase. Blowing and drifting
snow may develop as the fluffy snow gets pushed around, causing
travel problems on north-south roads.
On Wednesday, an unusually strong surface high, on the order of 1058
mb, will build southeast through the Dakotas, before settling into
the Ohio Valley by early Thursday. The strong pressure contrast will
result in northwest winds of 15-25 mph Tuesday night and Wednesday,
with some gusts to over 30 mph. Lobe of -24C air at 850 mb will
pivot through the Midwest on Wednesday. Highs on Wednesday likely to
remain below zero across the northern CWA, with lows Wednesday night
10-15 below zero north of I-74. Wind chill warnings and advisories
will be needed for late Tuesday night into Thursday morning, as most
of the forecast area sees wind chills 15-25 below with lower than
-25 across the north. Have decided to hold off on adding wind chill
headlines to the mix, due to the winter storm expected tonight
across much of the same area.
The next clipper system is projected to remain across southern
Canada on Thursday, dragging a cold front across northern IL
Thursday night. At this point, we are keeping snow out of the
forecast for Thur night. However, as the system becomes better
defined in a couple days, we may need to add a mention of light snow
for at least our northern counties.
Behind that cold front we will see a reinforcing push of cold air,
but not as cold as the mid-week airmass. We still expect very cold
conditions as wind chills remain below zero on Friday morning and
especially Saturday morning when -10F wind chills develop. For the
weekend, we are still seeing phasing differences in the northern and
southern jet branches. A couple of shortwaves could progress across
IL during the weekend, but timing remains a question. There would be
a period of light snow with any weak disturbances that move across
the area.
Some relief from the cold is projected for next Monday, as highs
climb into the upper 20s and lower 30s.
&&
.AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon)
ISSUED AT 1150 AM CST MON JAN 5 2015
Not much of a shift in the forecast overall. Mid level clouds
moving in just ahead of the Clipper system. Snow moving in this
afternoon and spreading through the evening. Dropping fcst to
IFR/LIFR with the heaviest of the snowfall. VV should be limited
particularly in PIA, BMI and CMI, associated with the heaviest of
the snowfall rates. Snowfall max generally between 00z and 06z,
though moderate snowfall in scattered areas possible between 06z
and 12z, though very small scale and not worth a mention just yet.
Switching the winds to more northwesterly after the system moves
out in the morning and breaking up the cigs mid
morning...starting the trend, though confidence in the timing is
low.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING until 6 AM CST Tuesday FOR ILZ027>031-037-
038-045-046.
WINTER WEATHER ADVISORY until 6 AM CST Tuesday FOR ILZ036-
041>044-053>057.
&&
$$
SHORT TERM...HJS/Shimon
LONG TERM...Shimon
AVIATION...HJS
AREA FORECAST DISCUSSION
NWS GOODLAND KS
457 PM MST TUE JAN 6 2015
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 134 PM MST TUE JAN 6 2015
WV IMAGERY AND RAP H5 ANALYSIS SHOW NW FLOW CONTINUING FROM THE THE
CANADIAN ROCKIES ACROSS THE PLAINS AND TO THE CENTRAL MISSISSIPPI
RIVER VALLEY. AT THE SURFACE SOUTHERLY FLOW IS IN PACE ACROSS OUR
CWA ON EASTERN EXTENT OF LEE TROUGH CENTERED OVER COLORADO.
CONTINUING TO MONITOR POSSIBLE IMPACTS OF STRONG COLD FRONT EXPECTED
TO MOVE INTO CWA TONIGHT.
REGARDING PRECIP CHANCES/TYPES...MOST PRECIPITATION WILL BE TIED
TO ELEVATED FRONTAL ZONE WHERE ISENTROPIC UPGLIDE AND FRONTOGENETIC
FORCING WILL BE IN PLACE LATER TONIGHT. BETTER MOISTURE/LIFT IS
ADVERTISED IN THE WEST WHERE MODEL QPF IS SHOWING BETTER PRECIP
SIGNAL...SO I RAISED POPS TO LIKELY CATEGORY IN COLORADO COUNTIES
09-12Z PERIOD. WHILE SATURATION DOES OCCUR BELOW 700MB...MOISTURE
ADVECTION IS WEAK AND THOUGHTS ARE ANY PRECIP AMOUNTS WILL BE VERY
LIGHT. PRECIP TYPE IS ANOTHER CONCERN. LOW LEVEL SATURATION
BEGINS IMMEDIATELY BEHIND SURFACE FRONT THIS EVENING...YET TEMP
PROFILES FAVOR SUPERCOOLED LIQUID. SATURATION AT TEMPS BELOW -8C
DOESNT OCCUR OVER OUR CWA UNTIL AFTER 09Z. I COULD SEE VERY LIGHT
FREEZING DRIZZLE DEVELOPING AHEAD OF THE MAIN AREA OF
PRECIP...TRANSITIONING TO SNOW...POSSIBLY SLEET (SUPERCOOLED
SATURATED LAYER IS AT LEAST 2500 FT DEEP). SINCE PRECIP SHOULD BE
LIGHT I AM NOT THINKING THIS WOULD AMOUNT TO MUCH IN THE WAY OF
ICE ACCUMULATIONS...BUT I CANT RULE OUT SOME SLICK SPOTS
DEVELOPING DUE TO A LIGHT GLAZE. REGARDING SNOW AMOUNTS...I CANT
SEE OUR CWA RECEIVING MUCH MORE THAN ONE INCH AND THIS WOULD
LIKELY BE LIMITED TO THE FAR WEST. SNOW MAY LINGER IN EASTERN
COLORADO INTO THE MID MORNING HOURS WEDNESDAY...BUT SHOULD
COMPLETELY TAPPER OFF BY THE AROUND MIDDAY.
WINDS WILL INCREASE IMMEDIATELY BEHIND THE FRONT THIS
EVENING...HOWEVER BEST PRESSURE RISES QUICKLY TRANSITION SOUTH.
BY TIME PRECIP IS OCCURRING I DO NOT THINK WE WOULD SEE STRONG
ENOUGH GUSTS TO CREATE A BLOWING SNOW THREAT. MAYBE MINOR DRIFTING
SNOW DUE TO WINDS IN THE 15-20 MPH RANGE (MAINLY IN EASTERN
COLORADO).
REGARDING TEMPERATURES/WIND CHILLS...VERY COLD AIR MASS MOVES BACK
OVER THE CWA AFTER 06Z...AND HOW LOW TEMPS GET WILL BE COMPLICATED
BY LIMITED RADIATIONAL COOLING DUE TO CLOUD COVER AND INCREASED
MIXING DUE TO POSSIBLE PRECIP/WIND. I STILL EXPECT MOST LOCATIONS TO
REACH THE SINGLE DIGITS FOR LOWS TONIGHT WITH THE BEST CHANCE FOR
MORNING TEMPS AROUND ZERO OR COLDER IN OUR NE CWA (MCCOOK/NORTON).
I THINK IT IS MORE LIKELY WE SEE A BIGGER DROP OFF IN WINDS
SIMILAR TO NAM SURFACE WINDS...AS SURFACE GRADIENT WEAKENS.
WHILE WIND CHILLS MAY BE AROUND -15F...BUT I AM NOT CONFIDENT
THIS WOULD BE WIDESPREAD OR PERSISTENT.
WITH ALL THIS SAID...NO ADVISORY (WINTER WEATHER OR WIND CHILL)
WILL BE ISSUED DURING THIS UPDATE...BUT WE WILL NEED TO MONITOR
FREEZING PRECIP COVERAGE AND WIND CHILLS.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 136 PM MST TUE JAN 6 2015
ARCTIC AIR WILL BEGIN TO MODIFY WEDNESDAY NIGHT WITH GUSTY SOUTH
WINDS. WESTERN AND SOUTHERN PARTS OF THE FORECAST AREA WILL
BRIEFLY BENEFIT FROM A WARM FRONTAL PASSAGE THURSDAY MORNING AND
EARLY AFTERNOON...BUT ANOTHER COLD FRONT WILL MOVE THROUGH BY MID
AFTERNOON BRINGING COLDER TEMPERATURES AND A WIND SHIFT TO THE
NORTHWEST. VERY SHALLOW MOISTURE WILL GRADUALLY WORK IN BEHIND THE
FRONT FROM THE NORTHEAST THURSDAY NIGHT. ALTHOUGH UPPER FORCING
WILL BE QUITE WEAK...MOISTURE WILL BE DEEP ENOUGH TO SUPPORT LIGHT
FROZEN/FREEZING PRECIPITATION BEGINNING OVERNIGHT AND CONTINUING
INTO FRIDAY GENERALLY ALONG AND WEST OF HIGHWAY 27 INCLUDING
NORTHEAST COLORADO. THE SATURATED LAYER WILL GENERALLY BE BETWEEN
-6C AND -10C THROUGH FRIDAY MORNING AND NOT REACH -12C UNTIL
FRIDAY AFTERNOON. SO EXPECT A GENERAL TRANSITION FROM FREEZING
DRIZZLE TO SLEET TO SNOW FROM THURSDAY NIGHT THROUGH FRIDAY
AFTERNOON WITH OCCASIONAL MIXES OF ALL 3 POSSIBLE. EVEN THOUGH QPF
WILL BE VERY LIGHT THERE COULD BE SOME TRAVEL PROBLEMS WITH THE
WINTRY MIX EXPECTED.
BEYOND FRIDAY...THE UPPER FLOW ACROSS THE CONUS WILL WEAKEN
CONSIDERABLY AS THE MAIN UPPER LOW PULLS AWAY INTO EASTERN
CANADA. NORTHWEST FLOW EARLY IN THE PERIOD WILL TRANSITION TO WEAK
RIDGING OVER THE WEEKEND THEN TO A SOUTHWEST FLOW EARLY NEXT WEEK
AHEAD OF A TROUGH DIGGING INTO THE GREAT BASIN AND CENTRAL
ROCKIES. PRECIPITATION CHANCES WILL BE SLIM TO NONE IN THIS
PATTERN. TEMPERATURES WILL VERY SLOWLY MODERATE BUT REMAIN
SLIGHTLY BELOW NORMAL.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 451 PM MST TUE JAN 6 2015
VFR CONDITIONS SHOULD DETERIORATE EARLY THIS EVENING AT KMCK AND
BY LATE EVENING AT KGLD AS A COLD FRONT MOVES THROUGH THE AREA.
FORECAST SOUNDINGS INDICATE THAT CONDITIONS SHOULD LOWER TO IFR
OVERNIGHT AS STRATUS AND FOG MOVE INTO THE AREA. CONDITIONS WILL
BE THE WORST ALONG THE LEADING EDGE OF THE FRONT. THERE IS A
SLIGHT CHANCE OF SOME PATCHY LIGHT FREEZING DRIZZLE AS WELL. CIGS
SHOULD START INCREASING TO VFR AT KMCK TOWARD SUNRISE. CONDITIONS
AT KGLD SHOULD IMPROVE BY MID TO LATE MORNING.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...024
AVIATION...FS
AREA FORECAST DISCUSSION
NWS GOODLAND KS
214 PM MST MON JAN 5 2015
.SHORT TERM...(TONIGHT AND TUESDAY)
ISSUED AT 213 PM MST MON JAN 5 2015
EARLY AFTERNOON WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOW NW FLOW
EXTENDING FROM THE CANADIAN ROCKIES TO THE CENTRAL MISSISSIPPI RIVER
VALLEY. A SHORTWAVE TROUGH IS CURRENTLY CENTERED OVER NORTH DAKOTA.
AT THE SURFACE LEE TROUGH HAS DEVELOPED WITH WARMING TEMPERATURES
ALONG FRONT RANGE AS A RESULT OF DOWNSLOPE IN THE CENTRAL ROCKIES.
LOW PRESSURE EXTENDS ACROSS WESTERN KANSAS.
THIS AFTERNOON...TEMPS HAVE STRUGGLED TO WARM AS A RESULT OF CLOUD
COVER AND SHALLOW INVERSION OVER ESTABLISHED SNOW PACK. SOUTHERLY
FLOW HAS MANAGED TO BRING WARMER TEMPS FROM FRONT RANGE TOWARDS
EASTERN PLAINS OF COLORADO...HOWEVER THESE HAVE STRUGGLED TO ADVECT
FURTHER EAST AS WEAKER FLOW HAS BEEN IN PLACE IN KS/NE. I WOULD
STILL EXPECT TEMPS TO REACH ABOVE FREEZING AT LEAST IN THE
WEST...BUT THERE MAY BE VERY LITTLE ADDITIONAL WARMING IN OUR EAST.
TONIGHT-TUESDAY...COLD FRONT DROPS SOUTH OVER THE CWA TONIGHT AS
SHORTWAVE TROUGH MOVES ACROSS NORTHERN PLAINS INTO NORTHERN
MISSISSIPPI VALLEY. DEEP DRY AIR MASS WILL REMAIN IN PLACE...SO NOT
EXPECTING ANY PRECIP. NAM/RAP SHOWING STRATUS/FOG DEVELOPING BEHIND
THIS FRONT...HOWEVER MODEL SOUNDINGS CONTINUE TO INDICATE THIS
SATURATED LAYER REMAINING VERY SHALLOW. I AM ALSO SKEPTICAL OF THE
BL CONDITIONS ADVERTISED IN NAM AS ITS SNOW DEPTH IS SIGNIFICANTLY
HIGHER THAN REALITY (SHOWING 5-12" ACROSS CWA WHEN IN REALITY IT
AVERAGES 1-3"). BL CONDITIONS MAY BE OVERLY INFLUENCED BY THIS FIELD
AND SINCE FOG/STRATUS NEVER MATERIALIZED LAST NIGHT I DECIDED TO
HOLD OFF MENTION IN GRIDS. WARM FRONT LIFT NORTH TUESDAY AS LEE
TROUGH REDEVELOPS. SAME ISSUES WITH WARMING TUESDAY AS TODAY AS
CLOUDS SNOW PACK POSSIBLY LIMITING MIXING. NUDGED HIGHS TUESDAY
TOWARD WHATS BEEN OBSERVED SO FAR TODAY. NOT A LOT OF CONFIDENCE IN
THESE PERIOD WITH ANYTHING OTHER THAN A DRY FORECAST.
.LONG TERM...(TUESDAY NIGHT THROUGH NEXT MONDAY)
ISSUED AT 213 PM MST MON JAN 5 2015
SHORTWAVE TROUGH EMBEDDED IN NORTHWEST FLOW WILL BRING A CHANCE
FOR VERY LIGHT SNOW TUESDAY NIGHT AND WEDNESDAY MORNING. SNOW
ACCUMULATIONS WILL BE LESS THAN AN INCH. COLD ARCTIC AIR WILL
SPILL IN BEHIND THE ASSOCIATED SURFACE FRONT WITH HIGH
TEMPERATURES ON WEDNESDAY IN THE TEENS. TEMPERATURES WILL MODERATE
ON THURSDAY WITH DOWNSLOPING SURFACE WINDS...BUT ANOTHER COLD
FRONT WILL ARRIVE THURSDAY AFTERNOON BRINGING A CHANCE FOR LIGHT
SNOW THURSDAY NIGHT AND FRIDAY MORNING. ACCUMULATIONS WILL AGAIN
BE VERY LIGHT...LESS THAN AN INCH EXPECTED. TEMPERATURES WILL NOT
BE QUITE AS COLD BEHIND THAT FRONT WITH HIGHS ON FRIDAY IN THE
20S. THE REMAINDER OF THE PERIOD WILL BE DRY WITH A ZONAL FLOW
DEVELOPING ACROSS THE CONUS. HOWEVER...TEMPERATURES WILL CONTINUE
TO BE BELOW NORMAL.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1026 AM MST MON JAN 5 2015
VFR CONDITIONS SHOULD PREVAIL THROUGH AT LEAST 06Z AT BOTH KGLD
AND KMCK TERMINALS. LOW CONFIDENCE IN FORECAST AFTER 06Z...AS
NAM/RAP SHOWING LOW VIS DEVELOPING LATE TONIGHT THROUGH THE MIDDLE
OF TUESDAY MORNING BEHIND COLD FRONT. I COULD SEE SOME MOISTURE
POOLING WITH LIGHT NORTHERLY WINDS BEHIND THE FRONT...HOWEVER
MODEL SOUNDINGS APPEAR VERY SHALLOW WITH THIS MOIST LAYER...AND
MODELS COULD BE OVERLY INFLUENCED BY SNOW PACK. GFS MAY HAVE
BETTER HANDLE AND SHOWS VFR PREVAILING. FOR NOW I KEPT VFR IN
FORECAST AND ONLY INTRODUCED 6SM BR GROUP FOR 9-16Z PERIODS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...024
AVIATION...DR
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
920 PM EST TUE JAN 6 2015
LATEST UPDATE...
UPDATE
.SYNOPSIS...
ISSUED AT 312 PM EST TUE JAN 6 2015
WINDY AND COLD WEATHER ARE EXPECTED THROUGH FRIDAY. EXPECT
SIGNIFICANT SNOW ACCUMULATIONS NEAR LAKE MICHIGAN TONIGHT INTO
WEDNESDAY.
A STORM SYSTEM MOVING THROUGH THE GREAT LAKES WILL BRING
SNOW TO THE ENTIRE AREA THURSDAY NIGHT INTO FRIDAY...BUT ONCE AGAIN
THE HEAVIEST SNOW WILL BE NEAR THE LAKE SHORE.
THE COLD WEATHER WILL CONTINUE THROUGH SATURDAY WITH ADDITIONAL SNOW
ACCUMULATIONS NEAR LAKE MICHIGAN. A SLOW WARM UP BEGINS SUNDAY AND
CONTINUES INTO NEXT WEEK.
&&
.UPDATE...
ISSUED AT 905 PM EST TUE JAN 6 2015
NO HEADLINE OR SIGNIFICANT FCST CHANGES ARE NECESSARY THIS
EVENING. WNW TO NW FLOW LES BANDS WILL GRADUALLY BECOME HEAVIER
AND MORE FOCUSED ACROSS OUR LAKESHORE COUNTIES VERY LATE THIS
EVENING AND OVERNIGHT AS H8 TEMPS CONTINUE TO FALL TO AROUND -24 C
BY 12Z WED. THE COMBINATION OF OCCASIONALLY HEAVY LAKE EFFECT SNOW
SHOWERS AND COLD TEMPS AND WINDY CONDITIONS WILL RESULT IN
HAZARDOUS TRAVEL CONDITIONS ACROSS THE ADVISORY AREA LATE TONIGHT
THROUGH MUCH OF WEDNESDAY.
&&
.SHORT TERM...(TONIGHT THROUGH THURSDAY NIGHT)
ISSUED AT 312 PM EST TUE JAN 6 2015
STORM TERM...(TONIGHT THROUGH WEDNESDAY)
I CONTINUED THE WINTER WEATHER ADVISORY I ISSUED AROUND NOON FOR
THE LAKE SHORE COUNTIES FROM AROUND 10 PM TONIGHT UNTIL WEDNESDAY
AFTERNOON. THE HIGH RESOLUTION MODELS (ARW...NMM...NAM AND AS FAR
OUT AS IT NOW GOES THE HRRR) ALL SHOW A DOMINANT SNOW BAND SETTING
UP FROM AROUND MUSKEGON THROUGH GRAND HAVEN THROUGH THE CITY OF
ALLEGAN AND THROUGH OSHTEMO BY 01 AM. THAT BAND ONLY VERY SLOWLY
ROTATES CLOSER TO THE LAKE SHORE BY 7 AM. FROM THERE IT REMAINS A
GOOD PART OF THE DAY ONLY TO ROTATES BACK INLAND SLIGHTLY LATE IN
THE DAY BUT BY THEN IT IS WEAKENING.
THE NAM...ARW...NMM...RAP AND HRRR ALL SHOW STRONG LIFT NEAR AND
JUST ABOVE THE DGZ... MOISTURE DEPTH TO 8000 FT...AND WINDS
NORTHWEST (310-320 DEGREES) WITH ONLY MINOR SHIFTING IN DIRECTION
BETWEEN 1 AM AND 2 PM WEDNESDAY IN THAT DOMINANT SNOW BAND LOCATION.
SOME LIMITING FACTORS WOULD BE THE BEST LIFT IS ABOVE THE DGZ...THE
DGZ IS NEARLY ON THE GROUND. EVEN SO THE LIFT IS IMPRESSIVE AND
PERSISTENT FOR OVER 12 HOURS IN NEARLY THE SAME LOCATIONS. SO...I
HAVE TO IMAGINE 6 TO 10 INCHES OF SNOW IS MORE THAN LIKELY IN THAT
AREA. I DO NOT SEE BLOWING SNOW AS A MAJOR ISSUE WITH THIS EVENT
SINCE WIND GUSTS OVER 30 MPH WILL BE LIMITED TO THE IMMEDIATE LAKE
SHORE (YOU HAVE TO BE ON THE BEACH TO GET WIND GUSTS HIGHER THAN 30
MPH). STILL THERE WILL BE SOME BLOWING AND DRIFTING SNOW AS WINDS
WILL BE GUSTING AT TIMES TO NEAR 25 MPH INLAND OF LAKE MICHIGAN. THE
ADVISORY SHOULD INCLUDE ALL OF THE LAKE SHORE COUNTIES FROM
MASON THROUGH VAN BUREN. I WILL HAVE LAKE COUNTY IN THE ADVISORY
TOO BUT IT WILL REALLY ONLY BE ITS EXTREME WESTERN SECTION THAT
WILL BE IMPACTED.
REST OF SHORT TERM...(WEDNESDAY NIGHT THROUGH THURSDAY NIGHT)
FORECAST CONCERNS AFTER WEDNESDAY DEAL WITH APPARENT TEMPERATURES
WEDNESDAY NIGHT AND THURSDAY AND THE ARRIVAL OF ANOTHER ARCTIC
FRONT THURSDAY NIGHT.
CERTAINLY THE COLD WEATHER WILL CONTINUE. A LARGE...1052MB...HIGH IS
PROGD TO SETTLE OVER THE PLAINS LATE WEDNESDAY. ALTHOUGH BOUNDARY
LAYER TEMPS WILL WARM...TEMPS OVER THE LAKE WILL STILL BE COLD
ENOUGH TO GENERATE ENOUGH INSTABILITY TO SUPPORT LAKE EFFECT SNOW.
GENERALLY AN INCH OR LESS IS EXPECTED. BREEZY CONDITIONS ARE STILL
EXPECTED AND IT/S POSSIBLE WE/LL NEED A WIND CHILL ADVISORY
WEDNESDAY NIGHT AND THURSDAY MORNING FOR ALL BUT THE LAKE SHORE
COUNTIES AS APPARENT TEMPERATURES LOOK LIKE THEY/LL BE AROUND -15 OR
SO. WE/LL TAKE ANOTHER LOOK AT THIS TONIGHT.
ANOTHER ARCTIC FRONT WILL MOVE THROUGH THURSDAY EVENING. H8 TEMPS
FALL TO AROUND -22C. THIS SYSTEM WILL BRING SOME SYNOPTIC SNOW AND
LAKE EFFECT SNOW AND MAY ACCUMULATE 3-6 INCHES...HIGHEST OVER THE
WESTERN CWA. WE MAY NEED AN ADVISORY FOR THAT TOO.
.LONG TERM...(FRIDAY THROUGH TUESDAY)
ISSUED AT 312 PM EST TUE JAN 6 2015
DUE TO A DEPARTING SHORTWAVE AND LAKE ENHANCEMENT... SNOW WILL BE
FALLING AS THE LONG TERM BEGINS. LAKE EFFECT SNOW SHOULD CONTINUE
THROUGH AT LEAST SATURDAY... WHEN CONDITIONS START TO BECOME
UNFAVORABLE. SATURDAY AFTERNOON... COULD SEE TEMPERATURES AT 850 MB
WARMING AND THE FLOW ALOFT BECOMING LESS CYCLONIC. A WEAK SHORTWAVE
MAY POSSIBLY PASS ACROSS THE AREA SUNDAY... BRIEFLY INCREASING THE
CHANCE FOR SNOW. HAVE SOME SNOW CONTINUING INTO SUNDAY NIGHT AND
THEN WENT WITH A DRY FORECAST THROUGH TUESDAY... AS THE NEXT SYSTEM
LOOKS TO BE SOUTH OF THE STATE.
TEMPERATURES WILL REMAIN COLD THROUGH THE LONG TERM. A MODERATING
TREND IS EXPECTED TO BEGIN SUNDAY NIGHT. HIGHS IN THE TEENS
FRIDAY... SATURDAY AND SUNDAY. WILL WARM INTO THE LOWER TO MID 20S
FOR MONDAY AND TUESDAY. THIS IS STILL A LITTLE BELOW NORMAL FOR THIS
TIME OF YEAR.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 710 PM EST TUE JAN 6 2015
A MIX OF MVFR AND VFR CONDITIONS CAN BE EXPECTED THIS EVENING
WITH CIGS GENERALLY 2500-3500 FT AND OCNL VSBYS OF 3-5SM IN LIGHT
SNOW AND AREAS OF BLOWING SNOW.
THE PASSAGE OF ANOTHER ARCTIC COLD FRONT AROUND OR SHORTLY AFTER
MIDNIGHT WILL SHIFT WESTERLY WINDS TO THE NORTHWEST. HEAVY LAKE
EFFECT SNOW WILL SET UP LATE TONIGHT INTO WEDNESDAY ALONG THE
SHORELINE INCLUDING MKG AND POSSIBLY AZO AS WELL... WITH
PERSISTENT IFR TO LIFR VSBYS IN SNOW AND BLOWING SNOW.
MEANWHILE INLAND LOCATIONS SHOULD BECOME PREDOMINATELY VFR LATE
TONIGHT INTO WEDNESDAY WITH THE PASSAGE OF THE COLD FRONT
ALTHOUGH THE NW WINDS WILL REMAIN BRISK AT 15-25 KTS.
&&
.MARINE...
ISSUED AT 312 PM EST TUE JAN 6 2015
TO SIMPLIFY THINGS...WE ENDED THE SCA A LITTLE EARLY AND BUMPED UP
THE GALE AND HEAVY FREEZING SPRAY WARNING TO BEGIN LATE THIS
AFTERNOON. WINDS WILL INCREASE AS THE ARCTIC FRONT MOVES THROUGH
TONIGHT AND WILL GUST TO 40 KNOTS. GIVEN TEMPERATURES IN THE TEENS
OVER THE LAKE...HEAVY FREEZING SPRAY IS EXPECTED AND MARINERS CAN
EXPECT SIGNIFICANT ICE ACCRETION. WINDS WILL DIMINISH WEDNESDAY
AFTERNOON BUT FREEZING SPRAY CAN BE EXPECTED THROUGH THURSDAY NIGHT.
&&
.HYDROLOGY...
ISSUED AT 1203 PM EST TUE JAN 6 2015
THE POTENTIAL FOR FREEZE UP ICE JAMS ON AREA RIVERS WILL CONTINUE
INTO THE WEEKEND. RIVERS ARE BECOMING ICE COVERED. AVERAGE AIR
TEMPERATURES WILL CONTINUE WELL BELOW 20 DEGREES... WITH HIGHS
ONLY IN THE TEENS THROUGH THE WEEK. THIS WILL AID IN ICE
FORMATION.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...WINTER WEATHER ADVISORY UNTIL 4 PM EST WEDNESDAY FOR MIZ037-038-
043-050-056-064-071.
LM...HEAVY FREEZING SPRAY WARNING UNTIL 7 PM EST WEDNESDAY FOR
LMZ844>849.
GALE WARNING UNTIL 4 PM EST WEDNESDAY FOR LMZ844>849.
&&
$$
UPDATE...LAURENS
SYNOPSIS...WDM
SHORT TERM...93
LONG TERM...63
AVIATION...MEADE
HYDROLOGY...63
MARINE...93
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
746 PM EST TUE JAN 6 2015
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 427 PM EST TUE JAN 6 2015
WV IMAGERY AND RUC ANALYSIS INDICATED A RIDGE OVER THE WRN CONUS AND
A BROAD TROUGH FROM NORTHEAST CANADA INTO THE ERN CONUS RESULTING IN
WNW CYCLONIC MID/UPPER LEVEL FLOW THROUGH THE NRN GREAT LAKES. A
SHORTWAVE TROUGH MOVING THROUGH UPPER MI WAS DRAGGING A SFC TROUGH
THROUGH THE AREA. OTHERWISE...A 1051 MB ARCTIC HIGH PRES OVER W
CNTRL CANADA RIDGING INTO THE PLAINS WAS SLOWLY BUILDING TO THE EAST
BRINGING VERY COLD AIR INTO THE REGION. UPSTREAM TEMPS OVER MUCH OF
NW ONTARIO RANGED FROM -5F TO -15F LATE THIS AFTERNOON.
320-340 FLOW LES IS EXPECTED TO INCREASE TONIGHT AS WINDS VEER THIS
LATE THIS AFTERNOON AND A REINFORCING BATCH OF VERY COLD AIR MOVES
INTO THE AREA. 850 MB TEMPS ARE EXPECTED TO DROP TO AROUND
-30C...RESULTING IN VERY HIGH INSTABILITY OVER THE LAKE...LAKE
INDUCED CAPE OVER 1K J/KG. HOWEVER....THE COLD WILL DROP THE DGZ
BELOW 3K FT...KEEPING SLR VALUES CLOSER TO 20/1. THE HIGHER RES
MODELS SUGGEST THAT THE STRONGEST LOW LEVEL CONV AND HEAVIEST LES
WILL DEVELOP INTO N CNTRL UPPER MI OVER ALGER COUNTY AND N
SCHOOLCRAFT COUNTY WHERE SNOWFALL TOTALS UP TO 10 INCHES ARE
POSSIBLE TONIGHT INTO WEDNESDAY. OVER THE WEST...THE SHORTER FETCH
AND LESS FAVORABLE LOW LEVEL CONV SHOULD LIMIT SNOWFALL AMOUNTS INTO
THE 2 TO 6 INCH RANGE. AN ADVY WAS ALSO ISSUED FOR MARQUETTE COUNTY
EVEN THOUGH OVERALL AMOUNTS ONLY IN THE 1 TO 4 INCH RANGE ARE
EXPECTED. LOCATIONS NEAR BIG BAY AND EAST OF HARVEY COULD SEE SOME
OCCASIONALLY HEAVY SNOW BANDS. M-28 BETWEEN HARVEY AND MUNISING
COULD ALSO SEE SOME OCCASIONAL WHITEOUT CONDITIONS AS NW WINDS GUST
INTO THE 30-40 MPH RANGE NEAR THE SHORE.
A WIND CHILL WARNING WAS POSTED FOR THE INTERIOR WEST WITH WIND
CHILLS DROPPING TO AROUND -35. THE STRONGER WINDS AND SOME LAKE
MODIFICATION WILL LIMIT TEMP FALL OVER THE REST OF THE CWA WITH MINS
IN THE -5F TO 10F RANGE. HOWEVER...THE 10-20 MPH WINDS WILL STILL BE
STRONG ENOUGH TO LOWER WIND CHILLS TO AROUND -30...SOLIDLY INTO THE
ADVY RANGE(-25 TO -35). CONDITIONS WILL ONLY SLOWLY MODERATE WED
MORNING AS THE GUSTY WINDS CONTINUE.
AS WINDS BACK STEADILY INTO WED AFTERNOON...THE LES WILL SHIFT AND
DIMINISH OVER MOST LOCATIONS NEAR LAKE SUPERIOR. HOWEVER....A MORE
FAVORABLE FETCH INTO THE KEWEENAW MAY BRING AN INCREASE IN LES
DURING THE AFTERNOON INTO THE EVENING.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 318 PM EST TUE JAN 6 2015
THE UPPER TROUGH THAT IS CURRENTLY COVERING EASTERN CANADA AND THE
GREAT LAKES REGION WILL REMAIN IN PLACE FOR MUCH OF THE LONG TERM
PERIOD BEFORE FINALLY LIFTING OUT OF THE AREA EARLY NEXT WEEK. WITH
THE TROUGH IN PLACE...WAVES OF COLD AIR WILL CONTINUE TO SWEEP
ACROSS THE REGION AND LEAD TO BELOW NORMAL TEMPERATURES AND LAKE
EFFECT SNOW.
LAKE EFFECT SNOW WILL BE ONGOING IN THE WEST-NORTHWEST WIND SNOW
BELTS ON WEDNESDAY NIGHT...AS THE AREA IS BETWEEN A LOW OVER HUDSON
BAY AND A HIGH IN THE MID MISSISSIPPI VALLEY. WITH THE HIGH
SHIFTING TO THE EAST THROUGH THE NIGHT...WOULD EXPECT THE LAKE
EFFECT TO TRANSITION TO THE WESTERLY WIND FAVORED
LOCATIONS...LARGELY OVER THE KEWEENAW AND RIGHT ALONG THE LAKE
SUPERIOR SHORELINE EAST OF MUNISING. INVERSION HEIGHTS DURING THIS
PERIOD LOOK TO BE AROUND 6-7KFT AND IT APPEARS DRIER AIR MOVING
INTO THE AREA WILL LIMIT THE INTENSITY OF THE OF THE LES WEDNESDAY
NIGHT AND CONTINUING INTO THURSDAY MORNING AS WINDS SHIFT MORE TO
THE SOUTHWEST AHEAD OF AN APPROACHING CLIPPER.
A SHORTWAVE DIVING SOUTHEAST OUT OF CANADA WILL STRENGTHEN A TROUGH
OVER NORTHERN ONTARIO AND MINNESOTA THURSDAY MORNING AND THEN DRAG
IT SOUTHEAST ACROSS THE UPPER GREAT LAKES REGION THURSDAY
AFTERNOON. A PERIOD OF STRONG BUT BRIEF MID LEVEL WARM AIR
ADVECTION WILL SWEEP ACROSS THE SOUTHERN HALF OF THE CWA DURING THE
LATE MORNING AND AFTERNOON HOURS. WILL CONTINUE TO SHOW A PERIOD OF
LIKELY POPS AS THAT CLIPPER MOVES THROUGH THE AREA. STILL THINK
SNOWFALL AMOUNTS WILL BE IN THE 0.5-2.0 INCH RANGE...BUT WILL NEED
TO KEEP AN EYE ON SNOW RATIOS AS SOME OF THE MODELS INDICATE A VERY
DEEP CLOUD WITHIN THE DGZ WHICH COULD PRODUCE RATIOS OF 25-30 TO
ONE.
BEHIND THE CLIPPER...ANOTHER ROUND OF LAKE EFFECT WILL DEVELOP AS
850MB TEMPS FALL FROM -16C AT 18Z THURSDAY TO -26C BY 12Z FRIDAY
UNDER NORTHWESTERLY WINDS. WITH THE DEEPER MOISTURE PRESENT AND
FAIRLY HIGH INVERSION HEIGHTS...EXPECT A PERIOD OF MODERATE SNOW
DURING THE EVENING HOURS BEFORE GRADUALLY DIMINISHING OVERNIGHT AS
INVERSION HEIGHTS LOWER. AS HAS BEEN THE CASE WITH THE LAST COUPLE
OF EVENTS...EXPECT THE COLD AIR TO LEAD TO SNOW RATIOS AND FINER
FLAKES...THUS LEADING TO SNOW THAT IS EFFICIENT AT REDUCING
VISIBILITIES. AS A STARTING POINT...HAVE PUT 12HR AMOUNTS OF 2-4IN
FOR THE NORTHWEST WINDS BELTS THURSDAY NIGHT AND IN THE
WEST-NORTHWEST WIND AREAS ON FRIDAY. THE GUSTY WINDS BEHIND THE
CLIPPER SYSTEM WILL LEAD TO ANOTHER NIGHT OF LOW WIND CHILLS...WITH
MUCH OF THE WESTERN HALF OF UPPER MICHIGAN IN THE -20 TO -30 DEGREE
RANGE.
THE POCKET OF VERY COLD AIR WILL SHIFT EAST OF THE AREA ON
FRIDAY...LEADING TO A VERY SLOW MODERATION TO TEMPERATURES ALOFT
UNDER WEST-NORTHWEST WINDS. THEREFORE...WOULD EXPECT LAKE EFFECT TO
TRANSITION TO THE WESTERLY WIND AREAS ON FRIDAY AND REMAIN THROUGH
MUCH OF THE WEEKEND...AS ANOTHER HIGH DROPS FROM THE NORTHERN
PLAINS...THROUGH THE MID MISSISSIPPI VALLEY AND INTO THE MID
ATLANTIC STATES. THE LAKE EFFECT WILL START TO DIMINISH SUNDAY
NIGHT AND MONDAY BEHIND THE FINAL SHORTWAVE SWEEPING ACROSS THE
AREA SUNDAY NIGHT AND WITH THE UPPER TROUGH SHIFTING
EAST-NORTHEAST. THAT WILL ALLOW A HIGH TO MOVE DIRECTLY ACROSS THE
UPPER GREAT LAKES REGION ON MONDAY. THE HIGH WILL SHIFT TO THE NEW
ENGLAND STATES ON TUESDAY...BUT KEEP A LINGERING RIDGE OVER THE
AREA. THE DRY AIR AND SUBSIDENCE WITH THE RIDGE...COMBINED WITH
MODERATING 850MB TEMPS TO AROUND -10C...WILL LEAD TO DIMINISHING
LES CHANCES AND TEMPERATURES STARTING TO TREND BACK TOWARDS NORMAL.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 710 PM EST TUE JAN 6 2015
AT CMX..LIFR TO OCCASIONAL VLIFR CONDITIONS ARE EXPECTED WITH
CONTINUED NW FLOW LES AND BLOWING SNOW. WITH INCOMING VERY COLD
ARCTIC AIR...SNOWFLAKES WILL BECOME FINER/SMALLER AND VERY EFFECTIVE
AT REDUCING VIS. AT KIWD...VEERING WINDS TO NW WILL DROP CONDITIONS
TO IFR/LIFR TONIGHT AS SNOW SHOWERS INCREASE. AT KSAW...EXPECT
IFR CONDITIONS TONIGHT IN NW FLOW LES AND BLSN. AS WINDS BACK
OFFSHORE W-SW WED AFTERNOON CONDITIONS SHOULD QUICKLY IMPROVE TO VFR
AT BOTH KIWD AND KSAW.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 427 PM EST TUE JAN 6 2015
MUCH OF THIS PERIOD WILL BE MARKED BY HEAVY FREEZING SPRAY...WITH
INTERMITTENT GALES. CURRENTLY HAVE HEAVY FREEZING SPRAY WARNINGS
POSTED ALL THE WAY THROUGH SATURDAY MORNING. ACTIVE WEATHER FORECAST
WITH GALE EVENTS AND HEAVY FREEZING SPRAY CAN BE EXPECTED THROUGH
SATURDAY.
THE NW GALES DEVELOPING TONIGHT WILL GRADUALLY BACK TO WRLY LATE WED
AND THEN DIMINISH ON THU. ANOTHER COLD FRONT MOVING THROUGH THU
NIGHT INTO FRI WILL BRING THE NEXT PERIOD OF NW GALES WHICH ARE
EXPECTED TO GRADUALLY DIMINISH LATE FRI NIGHT INTO SAT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WIND CHILL ADVISORY UNTIL 1 PM EST /NOON CST/ WEDNESDAY FOR
MIZ001>007-012-013-084-085.
LAKE EFFECT SNOW WARNING UNTIL 1 PM EST WEDNESDAY FOR MIZ006-085.
WINTER WEATHER ADVISORY UNTIL 7 PM EST WEDNESDAY FOR MIZ001-003.
LAKESHORE FLOOD ADVISORY UNTIL 7 AM EST WEDNESDAY FOR MIZ001>003.
LAKE EFFECT SNOW ADVISORY UNTIL 1 PM EST /NOON CST/ WEDNESDAY
FOR MIZ002-007-009-013-014.
WIND CHILL WARNING UNTIL NOON CST WEDNESDAY FOR MIZ009>011.
LAKESHORE FLOOD ADVISORY UNTIL 7 AM EST THURSDAY FOR MIZ005>007.
LAKE EFFECT SNOW ADVISORY UNTIL 10 AM EST WEDNESDAY FOR MIZ005.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING UNTIL 1 PM EST /NOON CST/ SATURDAY
FOR LSZ240>251-263>267.
GALE WARNING UNTIL 7 AM EST THURSDAY FOR LSZ243>245-248>251-
264>267.
GALE WARNING UNTIL 7 AM EST /6 AM CST/ WEDNESDAY FOR LSZ162-
240>242-263.
HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST /6 AM CST/ SATURDAY
FOR LSZ162.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...SRF
AVIATION...VOSS
MARINE...JLB
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
710 PM EST TUE JAN 6 2015
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 312 PM EST TUE JAN 6 2015
WINDY AND COLD WEATHER ARE EXPECTED THROUGH FRIDAY. EXPECT
SIGNIFICANT SNOW ACCUMULATIONS NEAR LAKE MICHIGAN TONIGHT INTO
WEDNESDAY.
A STORM SYSTEM MOVING THROUGH THE GREAT LAKES WILL BRING
SNOW TO THE ENTIRE AREA THURSDAY NIGHT INTO FRIDAY...BUT ONCE AGAIN
THE HEAVIEST SNOW WILL BE NEAR THE LAKE SHORE.
THE COLD WEATHER WILL CONTINUE THROUGH SATURDAY WITH ADDITIONAL SNOW
ACCUMULATIONS NEAR LAKE MICHIGAN. A SLOW WARM UP BEGINS SUNDAY AND
CONTINUES INTO NEXT WEEK.
&&
.SHORT TERM...(TONIGHT THROUGH THURSDAY NIGHT)
ISSUED AT 312 PM EST TUE JAN 6 2015
STORM TERM...(TONIGHT THROUGH WEDNESDAY)
I CONTINUED THE WINTER WEATHER ADVISORY I ISSUED AROUND NOON FOR
THE LAKE SHORE COUNTIES FROM AROUND 10 PM TONIGHT UNTIL WEDNESDAY
AFTERNOON. THE HIGH RESOLUTION MODELS (ARW...NMM...NAM AND AS FAR
OUT AS IT NOW GOES THE HRRR) ALL SHOW A DOMINANT SNOW BAND SETTING
UP FROM AROUND MUSKEGON THROUGH GRAND HAVEN THROUGH THE CITY OF
ALLEGAN AND THROUGH OSHTEMO BY 01 AM. THAT BAND ONLY VERY SLOWLY
ROTATES CLOSER TO THE LAKE SHORE BY 7 AM. FROM THERE IT REMAINS A
GOOD PART OF THE DAY ONLY TO ROTATES BACK INLAND SLIGHTLY LATE IN
THE DAY BUT BY THEN IT IS WEAKENING.
THE NAM...ARW...NMM...RAP AND HRRR ALL SHOW STRONG LIFT NEAR AND
JUST ABOVE THE DGZ... MOISTURE DEPTH TO 8000 FT...AND WINDS
NORTHWEST (310-320 DEGREES) WITH ONLY MINOR SHIFTING IN DIRECTION
BETWEEN 1 AM AND 2 PM WEDNESDAY IN THAT DOMINANT SNOW BAND LOCATION.
SOME LIMITING FACTORS WOULD BE THE BEST LIFT IS ABOVE THE DGZ...THE
DGZ IS NEARLY ON THE GROUND. EVEN SO THE LIFT IS IMPRESSIVE AND
PERSISTENT FOR OVER 12 HOURS IN NEARLY THE SAME LOCATIONS. SO...I
HAVE TO IMAGINE 6 TO 10 INCHES OF SNOW IS MORE THAN LIKELY IN THAT
AREA. I DO NOT SEE BLOWING SNOW AS A MAJOR ISSUE WITH THIS EVENT
SINCE WIND GUSTS OVER 30 MPH WILL BE LIMITED TO THE IMMEDIATE LAKE
SHORE (YOU HAVE TO BE ON THE BEACH TO GET WIND GUSTS HIGHER THAN 30
MPH). STILL THERE WILL BE SOME BLOWING AND DRIFTING SNOW AS WINDS
WILL BE GUSTING AT TIMES TO NEAR 25 MPH INLAND OF LAKE MICHIGAN. THE
ADVISORY SHOULD INCLUDE ALL OF THE LAKE SHORE COUNTIES FROM
MASON THROUGH VAN BUREN. I WILL HAVE LAKE COUNTY IN THE ADVISORY
TOO BUT IT WILL REALLY ONLY BE ITS EXTREME WESTERN SECTION THAT
WILL BE IMPACTED.
REST OF SHORT TERM...(WEDNESDAY NIGHT THROUGH THURSDAY NIGHT)
FORECAST CONCERNS AFTER WEDNESDAY DEAL WITH APPARENT TEMPERATURES
WEDNESDAY NIGHT AND THURSDAY AND THE ARRIVAL OF ANOTHER ARCTIC
FRONT THURSDAY NIGHT.
CERTAINLY THE COLD WEATHER WILL CONTINUE. A LARGE...1052MB...HIGH IS
PROGD TO SETTLE OVER THE PLAINS LATE WEDNESDAY. ALTHOUGH BOUNDARY
LAYER TEMPS WILL WARM...TEMPS OVER THE LAKE WILL STILL BE COLD
ENOUGH TO GENERATE ENOUGH INSTABILITY TO SUPPORT LAKE EFFECT SNOW.
GENERALLY AN INCH OR LESS IS EXPECTED. BREEZY CONDITIONS ARE STILL
EXPECTED AND IT/S POSSIBLE WE/LL NEED A WIND CHILL ADVISORY
WEDNESDAY NIGHT AND THURSDAY MORNING FOR ALL BUT THE LAKE SHORE
COUNTIES AS APPARENT TEMPERATURES LOOK LIKE THEY/LL BE AROUND -15 OR
SO. WE/LL TAKE ANOTHER LOOK AT THIS TONIGHT.
ANOTHER ARCTIC FRONT WILL MOVE THROUGH THURSDAY EVENING. H8 TEMPS
FALL TO AROUND -22C. THIS SYSTEM WILL BRING SOME SYNOPTIC SNOW AND
LAKE EFFECT SNOW AND MAY ACCUMULATE 3-6 INCHES...HIGHEST OVER THE
WESTERN CWA. WE MAY NEED AN ADVISORY FOR THAT TOO.
.LONG TERM...(FRIDAY THROUGH TUESDAY)
ISSUED AT 312 PM EST TUE JAN 6 2015
DUE TO A DEPARTING SHORTWAVE AND LAKE ENHANCEMENT... SNOW WILL BE
FALLING AS THE LONG TERM BEGINS. LAKE EFFECT SNOW SHOULD CONTINUE
THROUGH AT LEAST SATURDAY... WHEN CONDITIONS START TO BECOME
UNFAVORABLE. SATURDAY AFTERNOON... COULD SEE TEMPERATURES AT 850 MB
WARMING AND THE FLOW ALOFT BECOMING LESS CYCLONIC. A WEAK SHORTWAVE
MAY POSSIBLY PASS ACROSS THE AREA SUNDAY... BRIEFLY INCREASING THE
CHANCE FOR SNOW. HAVE SOME SNOW CONTINUING INTO SUNDAY NIGHT AND
THEN WENT WITH A DRY FORECAST THROUGH TUESDAY... AS THE NEXT SYSTEM
LOOKS TO BE SOUTH OF THE STATE.
TEMPERATURES WILL REMAIN COLD THROUGH THE LONG TERM. A MODERATING
TREND IS EXPECTED TO BEGIN SUNDAY NIGHT. HIGHS IN THE TEENS
FRIDAY... SATURDAY AND SUNDAY. WILL WARM INTO THE LOWER TO MID 20S
FOR MONDAY AND TUESDAY. THIS IS STILL A LITTLE BELOW NORMAL FOR THIS
TIME OF YEAR.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 710 PM EST TUE JAN 6 2015
A MIX OF MVFR AND VFR CONDITIONS CAN BE EXPECTED THIS EVENING
WITH CIGS GENERALLY 2500-3500 FT AND OCNL VSBYS OF 3-5SM IN LIGHT
SNOW AND AREAS OF BLOWING SNOW.
THE PASSAGE OF ANOTHER ARCTIC COLD FRONT AROUND OR SHORTLY AFTER
MIDNIGHT WILL SHIFT WESTERLY WINDS TO THE NORTHWEST. HEAVY LAKE
EFFECT SNOW WILL SET UP LATE TONIGHT INTO WEDNESDAY ALONG THE
SHORELINE INCLUDING MKG AND POSSIBLY AZO AS WELL... WITH
PERSISTENT IFR TO LIFR VSBYS IN SNOW AND BLOWING SNOW.
MEANWHILE INLAND LOCATIONS SHOULD BECOME PREDOMINATELY VFR LATE
TONIGHT INTO WEDNESDAY WITH THE PASSAGE OF THE COLD FRONT
ALTHOUGH THE NW WINDS WILL REMAIN BRISK AT 15-25 KTS.
&&
.MARINE...
ISSUED AT 312 PM EST TUE JAN 6 2015
TO SIMPLIFY THINGS...WE ENDED THE SCA A LITTLE EARLY AND BUMPED UP
THE GALE AND HEAVY FREEZING SPRAY WARNING TO BEGIN LATE THIS
AFTERNOON. WINDS WILL INCREASE AS THE ARCTIC FRONT MOVES THROUGH
TONIGHT AND WILL GUST TO 40 KNOTS. GIVEN TEMPERATURES IN THE TEENS
OVER THE LAKE...HEAVY FREEZING SPRAY IS EXPECTED AND MARINERS CAN
EXPECT SIGNIFICANT ICE ACCRETION. WINDS WILL DIMINISH WEDNESDAY
AFTERNOON BUT FREEZING SPRAY CAN BE EXPECTED THROUGH THURSDAY NIGHT.
&&
.HYDROLOGY...
ISSUED AT 1203 PM EST TUE JAN 6 2015
THE POTENTIAL FOR FREEZE UP ICE JAMS ON AREA RIVERS WILL CONTINUE
INTO THE WEEKEND. RIVERS ARE BECOMING ICE COVERED. AVERAGE AIR
TEMPERATURES WILL CONTINUE WELL BELOW 20 DEGREES... WITH HIGHS
ONLY IN THE TEENS THROUGH THE WEEK. THIS WILL AID IN ICE
FORMATION.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...WINTER WEATHER ADVISORY FROM 10 PM THIS EVENING TO 4 PM EST
WEDNESDAY FOR MIZ037-038-043-050-056-064-071.
LM...HEAVY FREEZING SPRAY WARNING UNTIL 7 PM EST WEDNESDAY FOR
LMZ844>849.
GALE WARNING UNTIL 4 PM EST WEDNESDAY FOR LMZ844>849.
&&
$$
SYNOPSIS...WDM
STORM TERM...WDM
SHORT TERM...93
LONG TERM...63
AVIATION...MEADE
HYDROLOGY...63
MARINE...93
AREA FORECAST DISCUSSION...UPDATED
NWS TWIN CITIES/CHANHASSEN MN
1203 PM CST MON JAN 5 2015
.UPDATE...
ISSUED AT 1029 AM CST MON JAN 5 2015
THE PREVIOUS FORECAST LOOKED PRETTY GOOD AND ONLY MINOR CHANGES
WERE NEEDED. LOADED STRAIGHT RAP HOURLY POPS THROUGH THIS
EVENING...WHICH ALLOWED FOR BETTER TIMING AND A MORE BINARY LOOK
TO THE POP GRIDS AS CONFIDENCE CONTINUES TO INCREASE. AMOUNTS
STILL LOOK TO BE IN THE 6-8 INCH RANGE IN MARTIN COUNTY WITH
AMOUNTS TAPERING OFF NORTH AND EAST OF HERE. MAY NOT SEE MUCH MORE
THAN VERY LIGHT SNOW OR FLURRIES NORTH OF I-94 WHERE THE COLUMN
WILL BE COLDER THAN THE DENDRITIC GROWTH ZONE LEAVING ONLY NEEDLES
FOR FLAKES. NO CHANGES TO THE HEADLINES ARE NEEDED ATTM.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 329 AM CST MON JAN 5 2015
SFC ANALYSIS THIS MRNG SHOWS HIGH PRES CENTERED OVER THE CENTRAL
CONUS...EXTENDING MORE N-S THAN E-W AND KEEPING MOCLR CONDS OVER
THE UPR MISS RIVER VALLEY WHILE ALSO KEEPING WLY WINDS IN PLACE.
TEMPS IN THE -10 TO -15 DEGREE RANGE WITH WINDS IN THE 8-15MPH
RANGE ARE EASILY CREATING WIND CHILLS IN THE -25 TO -40 DEG F
RANGE SO WILL MAINTAIN THE WIND CHILL WARNINGS AND ADVISORIES AS
THEY ARE CURRENTLY DELINEATED...LASTING THRU 16Z AT WHICH TIME
THERE IS EXPECTED TO BE ENOUGH IMPROVEMENT IN WINDS AND TEMPS TO
SEE WIND CHILLS INCREASE TO -25 DEG F OR HIGHER.
THE CONCERN THEN TURNS TO THE QUICK-HITTING CLIPPER SYSTEM THIS
AFTN THRU THIS EVE. MODELS HAVE AGAIN TRENDED EVER-SO-SLIGHTLY
FURTHER S AND LESS ON QPF. THE FOCUS STILL IS ON EXTREME SWRN
PORTIONS OF THE CWFA FOR POTENTIALLY HITTING 6+ INCHES OF
SNOW...BUT THERE DOES LOOK TO BE A TIGHT GRADIENT NEAR/OVER THE
MINNESOTA RIVER. THE NAM/SREF ARE STILL THE NORTHERNMOST OUTLIERS
WHILE CONSENSUS AMONG THE GFS/EC/GEM MAINTAIN OR EVEN PUSH S
SLIGHTLY THE MAIN SWATH OF -SN. AS SUCH...HAVE OPTED TO KEEP THE
WARNING AS-IS FOR THIS MRNG. AS FOR THE ADVY...THE TIGHT GRADIENT
AND SWD SHIFT MAY MAKE IT DIFFICULT TO HIT 3 INCHES FOR RENVILLE
THRU RICE COUNTIES. THAT SAID...THERE LOOKS TO BE MORE OF A WNW-
ESE ORIENTATION IN THE BAND OF SNOW RATHER THAN A NW-SE...AND THIS
WOULD FAVOR SLIGHTLY HIGHER AMOUNTS IN LAC QUI PARLE COUNTY TO
JUST OVER ADVISORY CRITERIA. THEREFORE...HAVE CONVERTED ALL
COUNTIES IN THE WINTER STORM WATCH TO A WINTER WEATHER ADVISORY
AND ALSO ADDED IN LAC QUI PARLE COUNTY. -SN LOOKS TO MOVE IN MID-
TO-LATE AFTN AND THE HEAVIEST DURG THE EVENING HOURS BEFORE
TAPERING OFF DURG THE EARLY MRNG HRS TUE. WINDS LOOK TO DROP OFF
ENOUGH SUCH THAT BLOWING SNOW WILL NOT BE A CONCERN...SO HAVE HELD
OFF ANY MENTION OF BLOWING/DRIFTING SNOW.
ONCE PAST THE FRIGID WIND CHILLS OF THIS MRNG...SLIGHT WAA
ASSOCIATED WITH THIS INCOMING CLIPPER SYSTEM WILL ALLOW HIGHS
TDA TO BE A COUPLE TO A FEW DEGREES HIGHER THAN WHAT WAS RECORDED
YDA. SIMILARLY...THE CLOUD COVER TNGT WITH THE PASSING SYSTEM WILL
KEEP MIN TEMPS UP SLIGHTLY FROM THIS MRNG...GENERALLY IN THE -5 TO
-10 DEG F RANGE FOR EARLY TUE MRNG.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 329 AM CST MON JAN 5 2015
THE MAIN STORIES OF THE LONG TERM PERIOD ARE THE VERY COLD
TEMPERATURES/WIND CHILLS AND THE POTENTIAL FOR BLOWING SNOW. LITTLE
PRECIPITATION EXPECTED THIS PERIOD...JUST A CHANCE OF LIGHT SNOW ON
THURSDAY.
BY TOMORROW MORNING...THE STORM WILL BE LONG GONE AND INCREASING
NORTHWEST WINDS WILL PUSH INTO THE REGION AS A STRENGTHENING
SURFACE HIGH IN SOUTHWESTERN CANADA BEGINS PUSHING SOUTHEAST
TOWARD OUR AREA. ANOTHER CORE OF ARCTIC AIR WILL PUSH SOUTH TOWARD
US ON TUESDAY AND HIGH TEMPERATURES WILL RECOVER LITTLE UNDER THE
STRONG NORTHWEST FLOW. SINGLE DIGIT HIGHS ARE LIKELY WITH WIND
CHILL VALUES IN THE -20S.
THE STRONG SURFACE HIGH /MSLP VALUES OF 1056-1060MB/ WILL DROP
INTO THE WESTERN DAKOTAS TUESDAY NIGHT. WITH IT...THE CORE OF
THE COLD WILL ROTATE SOUTHWARD AND EXTEND FROM THE GREAT LAKES
THROUGH MINNESOTA. WITH THE APPROACHING AND STRENGTHENING
HIGH...WIND SPEEDS LOOK TO MAXIMIZE DURING THE NIGHT. LOW
TEMPERATURES DURING THE NIGHT SHOULD HAVE NO PROBLEM FALLING INTO
THE -10S EVERYWHERE. WITH THESE TEMPERATURES AND THE WINDS
INCREASING TO GENERALLY 15-25MPH...DANGEROUSLY COLD WIND CHILL
VALUES IN THE -30 TO -40 RANGE ARE EXPECTED ACROSS THE FORECAST
AREA. WINDS WILL WEAKEN DURING THE DAY WEDNESDAY AS THE GRADIENT
WEAKENS...AND WIND CHILL VALUES WILL IMPROVE. THE SURFACE HIGH
WILL DIVE SOUTH OF US AND PUSH EAST WEDNESDAY NIGHT.
ON WEDNESDAY NIGHT...A SUBTLE SHORTWAVE WHICH STOOD OUT BEST AT
850MB /AND ASSOCIATED WEAK SURFACE LOW/...WILL MOVE EAST ACROSS
THE DAKOTAS TOWARD MINNESOTA. DECENT LOW LEVEL LIFT WILL BE SEEN
FOR A PERIOD FROM LATE WEDNESDAY NIGHT THROUGH THURSDAY MORNING
DUE TO WARM AIR ADVECTION FROM THE SOUTHWEST. BOTH THE GFS AND EC
INDICATE THIS LIFT MAY BE ENOUGH TO SQUEEZE OUT SOME LIGHT SNOW.
INTRODUCED SLIGHT CHANCE POPS ACROSS WESTERN MN LATE WEDNESDAY
NIGHT. SATURATION LOOKS TO BE MORE OF A SURE BET FARTHER EAST
DURING THE DAY THURSDAY. POPS WERE INCREASED TO CHANCE CATEGORY
ACROSS THE EASTERN HALF OF THE FA GIVEN DECENT AGREEMENT BETWEEN
THE GFS/EC.
AN ARCTIC FRONT WILL FOLLOW THIS WAVE AND WEAK SURFACE LOW
THURSDAY...AND ANOTHER BOUT OF 850MB TEMPS COLDER THAN -20C WILL
ADVECT SOUTHWARD THROUGH OUR AREA BY LATE THURSDAY NIGHT. THIS
SURGE WILL BE FLEETING THOUGH...THE JET WILL LIFT NORTH OF US BY
SATURDAY AND SOUTHERLY WINDS WILL ENSUE AS WE`LL BE ON THE
BACKSIDE OF A SURFACE HIGH MOVING TOWARD THE SOUTHERN GREAT LAKES.
HIGH TEMPERATURES WILL MODERATE BUT REMAIN BELOW NORMAL.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1142 AM CST MON JAN 5 2015
SNOW OVER THE DAKOTAS WILL SLIDE SOUTHEAST...WITH THE HEAVIEST
REMAINING ALONG AND SOUTH OF THE MN RIVER IN SOUTHWESTERN MN. LIFR
CONDITIONS ARE POSSIBLE LATE THIS AFTERNOON AND EARLY THIS
EVENING AT RWF. TO THE NORTH AND EAST...MAINLY MVFR CONDITIONS ARE
EXPECTED ALTHOUGH A FEW IFR BURSTS ARE POSSIBLE FROM AXN TO MSP
AND EAU. CONFIDENCE IN TIMING AND INTENSITY IS FAIRLY HIGH. WINDS
WILL BACK SOUTHEAST LATER TODAY...THEN BECOME WEST NORTHWEST
BEHIND THE SYSTEM TONIGHT.
KMSP...BIGGEST UNCERTAINTY IN THIS FORECAST IS THE PRECISE BEGINNING
AND ENDING TIMES OF THE SNOW...AND EVEN THAT IS FAIRLY CERTAIN.
THINK THE SNOW WILL START BETWEEN 23-00Z AND END AROUND MID
EVENING. MAINLY MVFR CONDITIONS ARE EXPECTED. SNOW ACCUMULATIONS
WILL BE ABOUT AN INCH.
/OUTLOOK FOR KMSP/
TUE...VFR. WINDS NW 10-20 KTS.
WED...VFR. WINDS W 10-15 KTS.
THU...VFR. WINDS SW 10-15 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR MNZ054-
064-065-067-073>077-083>085-093.
WINTER STORM WARNING UNTIL MIDNIGHT CST TONIGHT FOR MNZ082-091-
092.
WI...NONE.
&&
$$
UPDATE...BORGHOFF
SHORT TERM...JPC
LONG TERM...SPD
AVIATION...BORGHOFF
AREA FORECAST DISCUSSION...UPDATED
NWS TWIN CITIES/CHANHASSEN MN
1030 AM CST MON JAN 5 2015
.UPDATE...
ISSUED AT 1029 AM CST MON JAN 5 2015
THE PREVIOUS FORECAST LOOKED PRETTY GOOD AND ONLY MINOR CHANGES
WERE NEEDED. LOADED STRAIGHT RAP HOURLY POPS THROUGH THIS
EVENING...WHICH ALLOWED FOR BETTER TIMING AND A MORE BINARY LOOK
TO THE POP GRIDS AS CONFIDENCE CONTINUES TO INCREASE. AMOUNTS
STILL LOOK TO BE IN THE 6-8 INCH RANGE IN MARTIN COUNTY WITH
AMOUNTS TAPERING OFF NORTH AND EAST OF HERE. MAY NOT SEE MUCH MORE
THAN VERY LIGHT SNOW OR FLURRIES NORTH OF I-94 WHERE THE COLUMN
WILL BE COLDER THAN THE DENDRITIC GROWTH ZONE LEAVING ONLY NEEDLES
FOR FLAKES. NO CHANGES TO THE HEADLINES ARE NEEDED ATTM.
&&
.UPDATE...
ISSUED AT 653 AM CST MON JAN 5 2015
UPDATED TO INCLUDE 12Z AVIATION DISCUSSION BELOW...AND TO
DOWNGRADE THE WIND CHILL WARNING TO AN ADVISORY FOR THE NORTHERN
TIER OF COUNTIES. WINDS HAVE JUST ABOUT TOPPED OUT FOR THE
MORNING...AND HAVE EVEN DIMINISHED BEFORE PREVIOUSLY FORECASTED
SPEEDS...WHILE TEMPERATURES ARE NOT EXPECTED TO DROP ANY
FURTHER...OR A DEGREE OR SO AT BEST. THEREFORE...WITH MAYBE AN
ISOLATED -35 OR LOWER READING POSSIBLE AND NOT MORE WIDESPREAD
SUCH VALUES EXPECTED...HAVE OPTED TO DROP THE WARNING IN FAVOR OF
AN ADVISORY FOR THE DURATION TO 16Z.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 329 AM CST MON JAN 5 2015
SFC ANALYSIS THIS MRNG SHOWS HIGH PRES CENTERED OVER THE CENTRAL
CONUS...EXTENDING MORE N-S THAN E-W AND KEEPING MOCLR CONDS OVER
THE UPR MISS RIVER VALLEY WHILE ALSO KEEPING WLY WINDS IN PLACE.
TEMPS IN THE -10 TO -15 DEGREE RANGE WITH WINDS IN THE 8-15MPH
RANGE ARE EASILY CREATING WIND CHILLS IN THE -25 TO -40 DEG F
RANGE SO WILL MAINTAIN THE WIND CHILL WARNINGS AND ADVISORIES AS
THEY ARE CURRENTLY DELINEATED...LASTING THRU 16Z AT WHICH TIME
THERE IS EXPECTED TO BE ENOUGH IMPROVEMENT IN WINDS AND TEMPS TO
SEE WIND CHILLS INCREASE TO -25 DEG F OR HIGHER.
THE CONCERN THEN TURNS TO THE QUICK-HITTING CLIPPER SYSTEM THIS
AFTN THRU THIS EVE. MODELS HAVE AGAIN TRENDED EVER-SO-SLIGHTLY
FURTHER S AND LESS ON QPF. THE FOCUS STILL IS ON EXTREME SWRN
PORTIONS OF THE CWFA FOR POTENTIALLY HITTING 6+ INCHES OF
SNOW...BUT THERE DOES LOOK TO BE A TIGHT GRADIENT NEAR/OVER THE
MINNESOTA RIVER. THE NAM/SREF ARE STILL THE NORTHERNMOST OUTLIERS
WHILE CONSENSUS AMONG THE GFS/EC/GEM MAINTAIN OR EVEN PUSH S
SLIGHTLY THE MAIN SWATH OF -SN. AS SUCH...HAVE OPTED TO KEEP THE
WARNING AS-IS FOR THIS MRNG. AS FOR THE ADVY...THE TIGHT GRADIENT
AND SWD SHIFT MAY MAKE IT DIFFICULT TO HIT 3 INCHES FOR RENVILLE
THRU RICE COUNTIES. THAT SAID...THERE LOOKS TO BE MORE OF A WNW-
ESE ORIENTATION IN THE BAND OF SNOW RATHER THAN A NW-SE...AND THIS
WOULD FAVOR SLIGHTLY HIGHER AMOUNTS IN LAC QUI PARLE COUNTY TO
JUST OVER ADVISORY CRITERIA. THEREFORE...HAVE CONVERTED ALL
COUNTIES IN THE WINTER STORM WATCH TO A WINTER WEATHER ADVISORY
AND ALSO ADDED IN LAC QUI PARLE COUNTY. -SN LOOKS TO MOVE IN MID-
TO-LATE AFTN AND THE HEAVIEST DURG THE EVENING HOURS BEFORE
TAPERING OFF DURG THE EARLY MRNG HRS TUE. WINDS LOOK TO DROP OFF
ENOUGH SUCH THAT BLOWING SNOW WILL NOT BE A CONCERN...SO HAVE HELD
OFF ANY MENTION OF BLOWING/DRIFTING SNOW.
ONCE PAST THE FRIGID WIND CHILLS OF THIS MRNG...SLIGHT WAA
ASSOCIATED WITH THIS INCOMING CLIPPER SYSTEM WILL ALLOW HIGHS
TDA TO BE A COUPLE TO A FEW DEGREES HIGHER THAN WHAT WAS RECORDED
YDA. SIMILARLY...THE CLOUD COVER TNGT WITH THE PASSING SYSTEM WILL
KEEP MIN TEMPS UP SLIGHTLY FROM THIS MRNG...GENERALLY IN THE -5 TO
-10 DEG F RANGE FOR EARLY TUE MRNG.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 329 AM CST MON JAN 5 2015
THE MAIN STORIES OF THE LONG TERM PERIOD ARE THE VERY COLD
TEMPERATURES/WIND CHILLS AND THE POTENTIAL FOR BLOWING SNOW. LITTLE
PRECIPITATION EXPECTED THIS PERIOD...JUST A CHANCE OF LIGHT SNOW ON
THURSDAY.
BY TOMORROW MORNING...THE STORM WILL BE LONG GONE AND INCREASING
NORTHWEST WINDS WILL PUSH INTO THE REGION AS A STRENGTHENING
SURFACE HIGH IN SOUTHWESTERN CANADA BEGINS PUSHING SOUTHEAST
TOWARD OUR AREA. ANOTHER CORE OF ARCTIC AIR WILL PUSH SOUTH TOWARD
US ON TUESDAY AND HIGH TEMPERATURES WILL RECOVER LITTLE UNDER THE
STRONG NORTHWEST FLOW. SINGLE DIGIT HIGHS ARE LIKELY WITH WIND
CHILL VALUES IN THE -20S.
THE STRONG SURFACE HIGH /MSLP VALUES OF 1056-1060MB/ WILL DROP
INTO THE WESTERN DAKOTAS TUESDAY NIGHT. WITH IT...THE CORE OF
THE COLD WILL ROTATE SOUTHWARD AND EXTEND FROM THE GREAT LAKES
THROUGH MINNESOTA. WITH THE APPROACHING AND STRENGTHENING
HIGH...WIND SPEEDS LOOK TO MAXIMIZE DURING THE NIGHT. LOW
TEMPERATURES DURING THE NIGHT SHOULD HAVE NO PROBLEM FALLING INTO
THE -10S EVERYWHERE. WITH THESE TEMPERATURES AND THE WINDS
INCREASING TO GENERALLY 15-25MPH...DANGEROUSLY COLD WIND CHILL
VALUES IN THE -30 TO -40 RANGE ARE EXPECTED ACROSS THE FORECAST
AREA. WINDS WILL WEAKEN DURING THE DAY WEDNESDAY AS THE GRADIENT
WEAKENS...AND WIND CHILL VALUES WILL IMPROVE. THE SURFACE HIGH
WILL DIVE SOUTH OF US AND PUSH EAST WEDNESDAY NIGHT.
ON WEDNESDAY NIGHT...A SUBTLE SHORTWAVE WHICH STOOD OUT BEST AT
850MB /AND ASSOCIATED WEAK SURFACE LOW/...WILL MOVE EAST ACROSS
THE DAKOTAS TOWARD MINNESOTA. DECENT LOW LEVEL LIFT WILL BE SEEN
FOR A PERIOD FROM LATE WEDNESDAY NIGHT THROUGH THURSDAY MORNING
DUE TO WARM AIR ADVECTION FROM THE SOUTHWEST. BOTH THE GFS AND EC
INDICATE THIS LIFT MAY BE ENOUGH TO SQUEEZE OUT SOME LIGHT SNOW.
INTRODUCED SLIGHT CHANCE POPS ACROSS WESTERN MN LATE WEDNESDAY
NIGHT. SATURATION LOOKS TO BE MORE OF A SURE BET FARTHER EAST
DURING THE DAY THURSDAY. POPS WERE INCREASED TO CHANCE CATEGORY
ACROSS THE EASTERN HALF OF THE FA GIVEN DECENT AGREEMENT BETWEEN
THE GFS/EC.
AN ARCTIC FRONT WILL FOLLOW THIS WAVE AND WEAK SURFACE LOW
THURSDAY...AND ANOTHER BOUT OF 850MB TEMPS COLDER THAN -20C WILL
ADVECT SOUTHWARD THROUGH OUR AREA BY LATE THURSDAY NIGHT. THIS
SURGE WILL BE FLEETING THOUGH...THE JET WILL LIFT NORTH OF US BY
SATURDAY AND SOUTHERLY WINDS WILL ENSUE AS WE`LL BE ON THE
BACKSIDE OF A SURFACE HIGH MOVING TOWARD THE SOUTHERN GREAT LAKES.
HIGH TEMPERATURES WILL MODERATE BUT REMAIN BELOW NORMAL.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 653 AM CST MON JAN 5 2015
SKC CONDS THIS MRNG WILL GRADUALLY BE REPLACED BY HIGH CLOUDS THAT
WILL LOWER THRU THE DAY AS A CLIPPER LOW PRES SYSTEM ARRIVES FROM
THE SW. SYSTEM WILL TRACK TO THE S...SLIGHTLY FURTHER THEN PREV
FCST...SHUNTING THE HEAVIER SNOWFALL TO THE IOWA BORDER AND SWRN
MN. THUS...THE TERMINAL THAT LOOKS TO BE MOST AFFECTED WILL BE
KRWF WITH LESSER EFFECTS IN KMSP-KEAU AND NORTHWARD. BECAUSE OF
THE RELATIVE SPEED OF THE SYSTEM AND STRONG LIFT/DYNAMICS
ASSOCIATED WITH IT...HAVE BUILT IN A WINDOW OF IFR VSBY SNOW AT
ALL SITES. NOT LOOKING FOR CEILINGS TO DROP TO IFR WITH THE
SNOWFALL. CONDS QUICKLY IMPROVE LATE EVE THRU EARLY MRNG HRS BACK
TO VFR WITH MID-HIGH CLOUDS BY DAYBREAK TMRW MRNG. WINDS WILL BE
SHIFTING THROUGHOUT THE NEXT 24 HRS...BUT WITH SPEEDS GENERALLY
AOB 10 KT.
KMSP...VFR CONDS XPCTD THRU THIS AFTN THEN CONDS QUICKLY
DETERIORATE THIS EVE WITH THE ONSET OF -SN. THE SPEED OF THE
SYSTEM LOOK TO ALLOW VSBY TO DROP TO MVFR RIGHT OFF AND REMAIN
THERE THRU THE BULK OF THE EVENING. THERE IS THE POTENTIAL FOR A
HEAVIER BURST OR TWO...BRINGING VSBY DOWN TO IFR...BUT AM NOT
EXPECTING RATES OF 1 INCH/HOUR.
/OUTLOOK FOR KMSP/
TUE...VFR. WINDS NW 10-20 KTS.
WED...VFR. WINDS W 10-15 KTS.
THU...VFR. WINDS SW 10-15 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR MNZ054-
064-065-067-073>077-083>085-093.
WINTER STORM WARNING UNTIL MIDNIGHT CST TONIGHT FOR MNZ082-091-
092.
WI...NONE.
&&
$$
UPDATE...BORGHOFF
SHORT TERM...JPC
LONG TERM...SPD
AVIATION...JPC
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
1004 PM CST Tue Jan 6 2015
.UPDATE:
Issued at 1002 PM CST Tue Jan 6 2015
Band of snow over west central has been taking shape the past
couple of hours as band of mid level frontogenesis has been
strengthening per recent runs of the RAP. Reports under the band
have been generally light to moderate in intensity with little in
the way of accumulations. RAP shows that the frontogenesis will
move quickly across central and east central Missouri into
southwest Illinois through 10Z. Have gone with likely PoPs in the
path of this band with potential of up to 1/2 inch of snowfall
given the speed of this system. Otherwise the rest of the forecast
still looks on track with wind chills falling into advisory range
by early morning over northeast MO/west central IL.
Britt
&&
.SHORT TERM: (Tonight-Wednesday)
Issued at 345 PM CST Tue Jan 6 2015
Cold air in the wake of last night`s clipper currently building into
area, but the true motherload of Arctic air is still up in the
northern Plains and upper Mississippi Valley and charging our way.
It`s difficult to determine exactly where the leading edge of this
even colder AMS is, but going by NW winds gusting into the 20-30kt
range seems to suggest it has reached e SD and sw MN attm.
Latest hi-res and synoptic guidance generally supports going temp
and wind trends for tonight and into Wednesday, and by any measure
the next 24 hours are going to be extremely cold. Temperatures will
begin to drop over the next few hours but should really begin to
tumble after midnight when the next round of Arctic air hits, and by
mid morning Wednesday expect ambient air temps of -3 to -5 over our
N counties, with readings near 10 above hanging on in far s sections
of the FA. These temps, combined with the sustained NW winds of
15-20 mph will lead to bitterly cold wind chills...easily in the -15
to -25 range over the northern half of the CWA. Current wind chill
headlines still look to be on the mark, but I have expanded the
advisory to include another row of counties from Crawford Co MO to
Randolph Co IL to blend with headlines planned by SGF and PAH.
Due to the bare ground we should see a bit of a temperature bounce
during the afternoon, but it will be very minimal.
Models are still forecasting a quick shot of snow across the CWA
overnight, in entrance region of 160kt jet core over the lower Great
Lakes. 850-700mb frontogenetic forcing suggests a slightly more
northern track of this narrow snow band, and light snow is now
showing up on regional 88D imagery just west of FSD. So, have made
a slight nwd adjustment to the slight chance/low chance PoPs. Its
certainly possibly that there will be an extremely narrow corridor
where the PoPs should be much higher and that could receive some
accumulating snow, but this adjustment will have to wait until radar
echoes begin to show the orientation and location of this narrow
band.
An aside...we recently received a call from St. Francois County that
underground pops and booms are occurring. Believe these may be ice
or frost quakes...cryoseisms. If that is indeed the case, these
reports should certainly increase due to the aforementioned
temperature trends.
Truett
.LONG TERM: (Wednesday Night-Tuesday)
Issued at 336 PM CST Tue Jan 6 2015
(Wednesday Night through Friday)
Temperatures remain the primary forecast concern for the rest of
the work week as the midweek intrusion of Arctic air moves to the
east, followed by another...but less intense...round of Arctic air
on Friday.
Wednesday night`s lows will be interesting as the center of the
Arctic high tracks from eastern KS to the Ohio Valley. The night
will certainly begin very cold over our n counties, but the return
flow developing on the north side of the surface high combined
with some increase of mid and high clouds should inhibit a big
nocturnal temp drop, and actually expect a bit of a rebound in
temps in the 06-12z time frame due to the increase in mixing and
clouds that is progged over this area. However, With the ridge
axis hanging over over the eastern Ozarks during the predawn hours
temperatures in the south should fall most of the night, and it
may be that some locations here will be as cold as those in the
north. As mentioned yesterday it is difficult to get mins below
zero without snow cover, but it certainly looks like most areas
will be able to achive this on Wednesday night due to the strength
of the cold air.
The southeast push of the ridge across the area will also produce
some odd wind chill trends. Some areas in the advisory will likely
warm above criteria for a time on Wednesday evening, before the
increasing winds in the return flow drop them back into the
criteria by daybreak. It may well be that we will have to make
some adjustments in the headlines once we can better pin down
these trends.
No major changes to going forecasts for Thursday-Friday. The
return flow should produce a bit of a moderation on Thursday, with
temps dropping once again on Friday as the next batch of Arctic
air pours into the mid-Mississippi Valley. I did trend just a bit
colder on Friday night, as center of the next surface ridge
should be parked over the area for much of the night.
(Saturday-Tuesday)
Medium range guidance still indicates a very gradual moderation in
temps heading into the start of the new week as the flow pattern
transitions to a zonal flow look over the central CONUS. I`ve also
continued some chance snow PoPs in the Sunday-Tuesday time
frame...although the signals are certainly not strong, model consensus
does indicate some warm advection as well as dynamics will be
impacting the region during this time frame.
Truett
&&
.AVIATION: (For the 00z TAFs through 00z Wednesday Evening)
Issued at 537 PM CST Tue Jan 6 2015
Expect light snow to move over the area from the northwest this
evening. Current thinking is that VFR conditions will prevail for
a few hours this evening, then as light snow develops expect
ceilings to fall to between 2000-3000FT. Corresponding drop in
visibility will also occur, however not sure how low to go. Think
there will be areas of snow causing visibilities between 3-5SM,
and possibly pockets of 1-2SM though am less confident in the IFR
visibilities. Snow should end from north to south through the
early morning hours and there will be a corresponding rise in
ceilings and visibilities...tho some MVFR stratocumulus will
likely hang on until mid to late morning. Wind will be increasing
behind the arctic front which is the driver behind this snow.
Expect northwest wind to increase to 15 to 20kts sustained with
gusts to 30kts. This will obviously cause crosswind issues on any
southwest/northeast runways.
Specifics for KSTL:
VFR flight conditions are expected to prevail at Lambert through
the evening. An area of light snow should move over the terminal
from the northwest around midnight, causing ceilings and
visibilities to fall. Think there`s a good chance that
visibilities will fall to 3-5SM for a period after midnight.
Cannot rule out a visibility between 1-2SM for a short period, but
I am less confident in that. Wind will increase to northwest at 15
to 20kts with gusts to 30kts behind the arctic front which is
causing this snow. These gusty winds will continue into Wednesday.
MVFR stratocumulus will likely stick around through the morning
hours as well.
Carney
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...WIND CHILL ADVISORY from 8 AM to 10 PM CST Wednesday FOR
Crawford MO-St. Francois MO-Ste. Genevieve MO-Washington MO.
WIND CHILL ADVISORY from 6 AM Wednesday to 9 AM CST Thursday FOR
Audrain MO-Boone MO-Callaway MO-Cole MO-Franklin MO-
Gasconade MO-Jefferson MO-Lincoln MO-Marion MO-Moniteau MO-
Monroe MO-Montgomery MO-Osage MO-Pike MO-Ralls MO-Shelby MO-
St. Charles MO-St. Louis City MO-St. Louis MO-Warren MO.
WIND CHILL WARNING from 3 AM Wednesday to 9 AM CST Thursday FOR
Knox MO-Lewis MO.
IL...WIND CHILL ADVISORY from 8 AM to 10 PM CST Wednesday FOR
Randolph IL.
WIND CHILL ADVISORY from 6 AM Wednesday to 9 AM CST Thursday FOR
Bond IL-Calhoun IL-Clinton IL-Fayette IL-Greene IL-Jersey
IL-Macoupin IL-Madison IL-Marion IL-Monroe IL-Montgomery IL-
Pike IL-St. Clair IL-Washington IL.
WIND CHILL WARNING from 3 AM Wednesday to 9 AM CST Thursday FOR
Adams IL-Brown IL.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS BILLINGS MT
324 PM MST MON JAN 5 2015
.SHORT TERM...VALID FOR TUE AND WED...
WE HAVE MADE SOME RELATIVELY SIGNIFICANT CHANGES WITH THE FORECAST
ISSUANCE THIS AFTERNOON....AS THE MAIN AXIS OF SNOWFALL DURING THE
NEXT 36 HOURS LOOKS TO BE A BIT NORTHEAST OF EARLIER EXPECTATIONS.
WE BELIEVE THAT ADDITIONAL SNOWFALL BETWEEN 5 PM MST /00 UTC/ THIS
EVENING AND 5 AM /12 UTC/ WEDNESDAY MORNING WILL BE 3 TO LOCALLY 6
INCHES OVER PARTS OF THE AREA...CENTERED ALONG A LINE FROM ROUNDUP
TO HYSHAM...FORSYTH AND COLSTRIP.
AS OF 22 UTC...STRONG SURFACE PRESSURE RISES ON THE ORDER OF 6 MB/
3 HOURS ARE DROPPING THROUGH SOUTHEASTERN MT WITH WIND GUSTS OF 30
TO 45 MPH COMMON...CAUSING SOME BLOWING AND DRIFTING SNOW. WE FIND
IT INTERESTING THAT IN SPITE OF THE ARCTIC FRONTAL PASSAGE LOCALLY
AT BILLINGS A FEW HOURS AGO...TEMPERATURES ARE ONLY SLOWLY FALLING
INTO THE LOWER AND MID 20S F. THIS MAY BE REFLECTIVE OF A SOMEWHAT
SHALLOW WESTERN EDGE OF THE FRONTAL ZONE...WHICH WOULD CONFIRM THE
IDEA HELD IN THE 12 UTC GUIDANCE FOR THE FRONT TO NOT REACH AS FAR
WEST AS THE FOOTHILLS OR LIVINGSTON AS PREVIOUSLY EXPECTED. WE SAW
GREAT AGREEMENT IN THE 12 UTC GFS AND ECMWF MODELS FOR THE FRONTAL
ZONE TO STAY OFF THE FOOTHILLS...WITH FORCING THIS EVENING LOCATED
AROUND BILLINGS BEFORE IT ACTUALLY LIFTS BACK NORTHEASTWARD BEYOND
06 UTC. WARM AIR ADVECTION ALOFT WILL THEN FOCUS FROM ROUNDUP OVER
TO HYSHAM...MILES CITY AND BROADUS LATE TONIGHT INTO EARLY TUESDAY
FOR LIGHT SNOW PRODUCTION THERE. THE GUIDANCE THEN AGREES THAT THE
FRONTAL ZONE WILL SLOSH BACK SOUTHWEST DURING THE DAY SO THAT SNOW
PICKS UP AGAIN IN PLACES LIKE BILLINGS TUESDAY AFTERNOON AND RIGHT
INTO TUESDAY EVENING. HOWEVER...WITH THE MORE SHALLOW FRONTAL ZONE
ALOFT THE DENDRITIC GROWTH LAYER IS NOT NEARLY AS EFFICIENT ON ITS
WEST SIDE /OVER BILLINGS/ TUESDAY AFTERNOON AND EVENING AS PERHAPS
EARLIER EXPECTED.
SO...TAKING THE 12 UTC MULTI-MODEL CONSENSUS QPF INTO ACCOUNT WITH
A MIX OF COBB AND ROEBBER METHOD SNOW RATIOS YIELDED AN ADDITIONAL
3 TO LOCALLY 6 INCHES OF SNOW...THE LATTER MOST LIKELY AROUND THAT
HYSHAM AREA. THE HRRR AND TO A LESSER EXTENT THE 12 UTC NCEP WRF/S
/ARW AND NMM/ PRODUCE LITTLE MOISTURE FROM NORTHERN PARK COUNTY TO
LIVINGSTON...NYE OR RED LODGE TONIGHT. RECENT RADAR AND WEB CAMERA
IMAGES DO SHOW SOME SNOW AT RED LODGE THOUGH SO WE HAVE DECIDED TO
KEEP THE ADVISORY GOING IN THE FOOTHILLS FOR A WHILE...BUT DROPPED
THE HEADLINES FOR NORTHERN PARK COUNTY AND LIVINGSTON. WE SWITCHED
WARNINGS BACK TO ADVISORIES FOR YELLOWSTONE...MUSSELSHELL AND EVEN
TREASURE COUNTY TOO SINCE THEY WERE MAINLY ISSUED FOR THE SNOWFALL
WHICH COULD HAVE BEEN HEAVIER IN PLACES LIKE BILLINGS TODAY...WITH
A COUPLE INCHES OVER THE NEXT 36 HOURS NOT ENOUGH TO KEEP WARNINGS
GOING...ESPECIALLY ONCE WINDS SUBSIDE THIS EVENING. WE LEFT UP THE
WARNINGS FOR BIG HORN AND SOUTHERN ROSEBUD COUNTY FOR NOW BASED ON
RECENT RADAR TRENDS...BUT THE EVENING OR MIDNIGHT SHIFTS SHOULD BE
ABLE TO REVERT THEM OVER TO ADVISORIES AT SOME POINT TOO ONCE THIS
AFTERNOON/S SNOW AND WINDS SETTLE DOWN.
WE NEED TO STRESS THAT THERE ARE STILL NUANCES TO WORK OUT IN THIS
SITUATION AND SO ADDITIONAL FORECAST ADJUSTMENTS ARE LIKELY IN THE
NEXT FEW FORECAST SHIFTS. FOR EXAMPLE...AFTERNOON HRRR SIMULATIONS
SHOW SOME FREEZING DRIZZLE OR VERY LIGHT FREEZING RAIN THREAT NEAR
THE WESTERN SIDE OF THE RETREATING ARCTIC FRONT LATE TONIGHT WHICH
WOULD INCLUDE THE BILLINGS AREA. CONFIDENCE IS NOT HIGH ENOUGH FOR
US TO INCLUDE THAT IN THE FORECAST...BUT IT WILL BEAR MONITORING.
BY WEDNESDAY...THE SNOW MACHINE WILL HAVE SHUT DOWN AND WE WILL BE
IN A FAVORABLE PATTERN TO WARM UP SOMEWHAT...ALBEIT REGULATED BY A
RELATIVELY DEEP SNOW PACK IN MANY AREAS. SCHULTZ
.LONG TERM...VALID FOR THU...FRI...SAT...SUN...MON...
EXTENDED MODELS OVERALL ARE IN FAIRLY GOOD AGREEMENT. AN
UNSETTLED NORTHWEST FLOW ALOFT WILL CONTINUE THURSDAY AS ANOTHER
DISTURBANCE MOVES ACROSS THE FORECAST AREA. THIS WILL BRING
ANOTHER SHOT OF ARCTIC AIR ALONG WITH A CHANCE FOR LIGHT SNOW. THE
RIDGE AXIS THAT HAS BEEN OVER THE PACIFIC NORTHWEST COAST
RESULTING IN THE NORTHWEST FLOW ALOFT WE HAVE EXPERIENCED FOR
QUITE A FEW DAYS NOW WILL BEGIN TO SHIFT EAST FRIDAY INTO NEXT
WEEKEND ALLOWING FOR THE VERY COLD ARCTIC AIR TO SLOWLY RETREAT.
ANOTHER DISTURBANCE LOOKS TO CROSS THE AREA SATURDAY RESULTING IN
ANOTHER CHANCE FOR LIGHT SNOW. HOWEVER...AT THIS TIME...BOTH
DISTURBANCES ARE NOT NEARLY AS STRONG NOR DYNAMIC AND MOISTURE
LADEN HAS HAS BEEN THE CASE THE PAST SEVERAL DAYS.
MODELS SHOW THE ARCTIC BOUNDARY WOBBLING BACK AND FORTH ACROSS
THE CENTRAL PORTIONS OF OUR FORECAST AREA THURSDAY THROUGH
SATURDAY RESULTING IN LARGE TEMPERATURE DIFFERENCES BETWEEN OUR
EASTERN AND WESTERN LOCATIONS. MODELS THEN SHOW THE ARCTIC PULLING
OUT OF THE AREA SUNDAY INTO MONDAY. TEMPERATURES WILL STILL BE A
GOOD 10 DEGREES BELOW NORMAL SUNDAY INTO MONDAY BUT NOT NEARLY AS
COLD AS THE PAST SEVERAL DAYS. HOOLEY
&&
.AVIATION...
AREAS OF LIGHT TO MODERATE SNOW WILL CONTINUE ACROSS THE FORECAST
AREA FOR THE REMAINDER OF THIS AFTERNOON AND THROUGH THE OVERNIGHT
HOURS. THE BEST LOCATIONS FOR THE HEAVIER SNOW WILL BE ABOUT 40
MILES EAST AND WEST OF A KSHR-KBIL-ROUNDUP LINE. MVFR TO IFR
CONDITIONS WILL CONTINUE TO PREVAIL THROUGH TONIGHT WITH AREAS OF
LIFR IN THE HEAVIER SNOW BANDS. THE MOUNTAINS WILL BE OBSCURED
WELL INTO THE DAY TUESDAY. HOOLEY
&&
.PRELIMINARY POINT TEMP/POPS...
TUE WED THU FRI SAT SUN MON
-----------------------------------------------------------
BIL 012/017 002/026 020/025 000/013 008/021 012/026 011/026
+7/S 71/E 02/J 21/B 22/J 21/B 11/B
LVM 028/039 011/044 026/034 011/028 021/036 021/035 019/032
42/S 21/N 01/B 22/J 22/J 21/B 11/B
HDN 010/017 002/025 016/026 905/016 004/022 004/025 005/025
+9/S 71/E 02/J 11/B 22/J 21/B 11/U
MLS 904/010 911/018 012/018 910/009 905/013 903/021 000/021
59/S 41/E 12/J 11/B 21/B 11/B 10/B
4BQ 006/014 902/024 017/024 905/011 004/020 003/021 005/023
78/S 51/E 02/J 11/B 11/B 11/B 10/U
BHK 908/008 914/014 010/018 909/004 904/012 902/016 000/020
16/S 20/B 12/J 10/B 11/B 11/B 10/B
SHR 011/027 005/031 022/031 901/019 012/029 010/028 010/027
96/S 61/B 02/J 12/J 12/J 21/B 11/U
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...WINTER WEATHER ADVISORY IN EFFECT UNTIL 6 AM MST WEDNESDAY
FOR ZONES 28>37-39-41-42.
WINTER STORM WARNING IN EFFECT UNTIL 6 AM MST WEDNESDAY FOR
ZONES 38-57-58-63-67-68.
WINTER WEATHER ADVISORY IN EFFECT UNTIL 6 AM MST TUESDAY FOR
ZONES 56-66.
WY...WINTER STORM WARNING IN EFFECT UNTIL 6 AM MST WEDNESDAY FOR
ZONE 98.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
1106 AM MST MON JAN 5 2015
.UPDATE...
WE CANCELLED THE HIGH WIND WARNING FOR LIVINGSTON AND NYE NOW WITH
PEAK GUSTS ONLY NEAR 50 MPH AS OF 1030 AM MST. WE ALSO TWEAKED THE
FORECAST HIGHS AND HOURLY TEMPERATURES TODAY AS TEMPERATURES AS OF
1045 AM MST HAVE RISEN WELL INTO THE MID 30S F EVEN IN BILLINGS IN
ADVANCE OF THE ARCTIC FRONT. THAT ARCTIC FRONT JUST SURGED THROUGH
JUDITH GAP RECENTLY AND WILL CONTINUE BLASTING SOUTH OVER THE NEXT
SEVERAL HOURS. WE STILL EXPECT SNOW TO FILL BACK IN ONCE THE FRONT
PASSES BILLINGS BY MID TO LATE AFTERNOON...BUT HOW MUCH SNOW FALLS
IS ALSO STILL IN SOME QUESTION. WE WILL CONTINUE TO MONITOR TRENDS
AND INCOMING MODEL DATA...WITH SOME ADDITIONAL CHANGES LIKELY WITH
THE AFTERNOON FORECAST RELEASE OVER THOSE MENTIONED BELOW. SCHULTZ
PREVIOUS FORECAST UPDATE...ISSUED AT 910 AM MST MON JAN 5 2015...
THE MAIN FORECAST CHANGE THIS MORNING WAS TO LOWER SNOW TOTALS FOR
TODAY OVER SOUTH CENTRAL MT...ESPECIALLY AROUND BILLINGS. THE LOW-
LEVEL DOWNSLOPE FLOW ON THE SOUTH SIDE OF A SURFACE LOW LOCATED IN
CENTRAL MT NEAR LEWISTOWN AS OF 16 UTC IS INHIBITING SNOWFALL THUS
FAR THIS MORNING...AND THIS SITUATION WILL NOT CHANGE MUCH THROUGH
THE MID TO LATE AFTERNOON WHEN THE ARCTIC FRONT RUSHES SOUTH...AND
THE WINDS SWITCH BACK AROUND THE THE NORTHEAST IN BILLINGS. RECENT
HIGH-RESOLUTION MODEL GUIDANCE SUGGESTS THAT MIGHT NOT OCCUR UNTIL
VERY LATE AFTERNOON AND IN SOME OF THOSE SIMULATIONS NOT UNTIL THE
EARLY EVENING HOURS. SO...WE CUT BACK ON SNOWFALL TOTALS TODAY FOR
THE CITY AND SURROUNDING AREAS. THE ARCTIC FRONT JUST SURGED SOUTH
THROUGH GREAT FALLS AT 9 AM...WHICH TYPICALLY MEANS IT COULD REACH
BILLINGS BY 3 PM WITH SNOW THEN PICKING UP AFTER THAT TIME. WE ARE
STILL CARRYING ABOUT 2 INCHES TOTAL FOR TODAY IN BILLINGS...BUT IT
LOOKS LIKE IF WE GET THAT MUCH IT WILL BE MAINLY IN THE AFTERNOON.
IN CONTRAST...SNOW IS FALLING LIKE EXPECTED IN SOUTHEASTERN MT AND
VISIBILITY IS REDUCED TO 1/2SM IN MILES CITY AND BAKER AT THE MID-
MORNING HOUR. WE STILL EXPECT 3 TO 6 INCHES OF SNOW IN TOTAL TODAY
OVER SOUTHEASTERN MT.
WE ARE CHOOSING TO LEAVE THE HIGH WIND WARNING UP AT LIVINGSTON AT
THIS POINT GIVEN TRAVEL IMPACTS THERE...EVEN THOUGH WINDS ARE THUS
FAR NOT NOT AS STRONG AS EXPECTED. WE WILL REVISIT THAT DURING THE
LATE MORNING HOURS...ALONG WITH THE REST OF THE FORECAST FOR TODAY
AND INTO TONIGHT...WHICH IS A VERY DIFFICULT ONE WHICH MAY REQUIRE
FURTHER ADJUSTMENTS. SCHULTZ
&&
.SHORT TERM...VALID FOR TDY AND TUE...
VERY COMPLEX AND DYNAMIC WEATHER PATTERN TODAY...AND ONE THAT
WILL BE VERY DIFFICULT TO PINPOINT EXACT RESULTS...EVEN THIS CLOSE
IN TIME. MODELS HAVE A GENERAL AGREEMENT ON THE PATTERN...BUT
DISPLAY SUBTLE DIFFERENCES THAT COULD HAVE MAJOR SNOW/COLD
IMPLICATIONS. WILL STAY WITH A CONSENSUS GFS/EC MIX AND KEEP THE
MAJORITY OF THE FORECAST IN TACT.
FOR TODAY...VERY IMPRESSIVE SURFACE PRESSURE FALLS WERE OCCURRING
OVER NORTHERN MONTANA...RIGHT ALONG THE CANADIAN BORDER. THIS WAS
IN RESPONSE TO 170KT JET MAX SLIDING INTO NORTHEAST MONTANA. THIS
SCENARIO WILL ALLOW A LEE TROUGH TO QUICKLY DEVELOP AND GENERATE
STRONG WINDS AT LIVINGSTON THIS MORNING. WINDS ALREADY INCREASING
WITH SOME GUSTS TO 50 MPH AT LIVINGSTON. SOME MODEL GUIDANCE HAS
BACKED OFF ON WARNING TYPE OF WINDS...WHILE OTHER HAVE NOT. WILL
KEEP WARNING GOING.
THE FORMATION OF A SURFACE LOW FROM THE PRESSURE FALLS OVER THE
NORTH WILL HAVE HUGE RAMIFICATIONS ON OUR FORECAST TODAY. A
FARTHER NORTHWARD DEVELOPING LOW WOULD ALLOW FOR MORE DOWNSLOPE
FLOW OVER SOUTH CENTRAL MONTANA. THIS WOULD PROVIDE A WARMER
MORNING AND PUSH SOME OF THE HEAVIER SNOW EASTWARD AWAY FROM
BILLINGS. A FARTHER SOUTH LOW WOULD BE COLDER AND BRING THE
HEAVIER SNOW SOUTH AND WEST INTO BILLINGS. RADAR IMAGERY WAS
FILLING IN OVER WESTERN AND CENTRAL ZONES THIS MORNING...BUT HAS
SHOWN A DOWNSLOPE SIGNATURE OVERNIGHT. LOOKS LIKE THE RADAR IS
FILLING IN SIMILARLY TO THE HRRR WHICH PUTS THE HEAVIEST SNOW
EAST OF BILLINGS THIS MORNING WITH LIGHTER SNOW OVER WESTERN
YELLOWSTONE COUNTY. WILL GO IN THAT DIRECTION AND LIGHTEN UP
MORNING SNOWFALL OVER BILLINGS. STRONG WARM AIR ADVECTION WILL
SPREAD HEAVIER SNOW EAST OF BILLINGS INTO SOUTHEAST MONTANA AND
ADVISORIES FOR THE EAST LOOK GOOD.
ONCE THE SURFACE LOW DROPS INTO NORTHEAST WYOMING...THE
REINFORCING ARCTIC SURGE WILL DRIVE BACK IN WITH FALLING
TEMPERATURES IN THE AFTERNOON AND SNOW DEVELOPING. THIS IS THE
PERIOD OF HEAVIEST SNOW FOR BILLINGS...THIS AFTERNOON AND EVENING.
ARCTIC SHOULD GET INTO WESTERN ZONES TOO AND THE FOOTHILLS WILL
RECEIVE STRONG UPSLOPE FLOW THIS AFTERNOON AND TONIGHT. WILL ISSUE
A WINTER WEATHER ADVISORY FOR THE BEARTOOTH AND RED LODGE
FOOTHILLS FOR THIS TIME PERIOD. LIVINGSTON WILL BE A CHALLENGE
TODAY BECAUSE WARMER AIR WILL KEEP ACCUMULATIONS DOWN...BUT
BLOWING SNOW WILL BE AN ISSUE THIS MORNING. ALSO...BELIEVE THE
ARCTIC WILL SURGE BACK IN THERE LATE THIS AFTERNOON. LIVINGSTON
COULD GET WARNING AMOUNTS AS INSTABILITY WAS DECENT WITH
850-500MB LAPSE RATES APPROACHING 6C. WILL NEED TO BE WATCHED.
ARCTIC BOUNDARY HANGS UP OVER WESTERN ZONES TONIGHT AND WILL GET
AN OVER RUNNING SNOWFALL FOR TONIGHT THROUGH TUESDAY NIGHT. MODELS
KEEP THE FOOTHILLS OUT OF THE BEST OVER RUNNING WITH 700MB WINDS
REMAINING OUT OF THE NORTHWEST. THEREFORE WILL LIMIT THE
ADVISORIES OF NYE AND RED LODGE TO TODAY AND TONIGHT. SHOULD SEE 2
TO 4 INCH SNOW TOTALS EACH 12 HOURS THROUGH TUESDAY NIGHT OVER THE
REST OF THE FORECAST AREA. THE SNOW WILL COME TO AN END LATE
TUESDAY NIGHT. TWH
.LONG TERM...VALID FOR WED...THU...FRI...SAT...SUN...
FOR THE EXTENDED...MODELS CONTINUE TO SHOW THE REPRIEVE FROM THE
SNOWFALL WEDNESDAY. THE RIDGE ALONG THE WEST COAST WILL PUSH
EAST...MOVING THE ARCTIC AIR OUT OF THE AREA. TEMPERATURES WILL
RETURN MORE NORMAL VALUES...THOUGH THE EASTERN PLAINS MAY NOT HAVE
AS MUCH OF A RECOVERY.
THURSDAY ANOTHER SHORTWAVE WILL MOVE THROUGH THE NORTHWEST FLOW.
THIS WILL PROVIDE JUST ENOUGH INSTABILITY THAT MORE COLD AND SOME
LIGHT SNOW WILL MOVE BACK INTO THE AREA. FORCING IS VERY WEAK
WITH THIS...SO CONTINUE TO EXPECT MUCH LIGHTER SNOWFALL
ACCUMULATIONS. ANOTHER WEAK WAVE WILL MOVE THROUGH SUNDAY GIVING
THE AREA ANOTHER SHOT AT SOME LIGHT SNOW. AGAIN NOT MUCH FORCING
WITH THIS SO AMOUNTS WILL BE MUCH LIGHTER. TEMPERATURES WILL BE
SLIGHTLY BELOW NORMAL GOING THROUGH THE WEEKEND. THERE IS SUBTLE
TIMING DIFFERENCES BETWEEN THE MODELS...SO CURRENTLY GOING WITH A
BLEND.
ONE CAVEAT WITH TEMPERATURES THROUGH THE EXTENDED WILL BE HOW
MUCH SNOW PACK IS ON THE GROUND. REIMER
&&
.AVIATION...
STRONG WIND GUSTS AROUND 45 KTS WILL CONTINUE IN THE KLVM AREA
THROUGH THE REMAINDER OF THE MORNING RESULTING IN REDUCED
VISIBILITIES DUE TO BLOWING SNOW. AREAS OF LIGHT TO MODERATE SNOW
WILL CONTINUE ACROSS THE ENTIRE AREA TODAY. THE KBIL AREA MAY
CONTINUE TO SEE A BREAK IN THE SNOW THROUGH MOST OF THE DAY BUT
THE HEAVIER SNOW IS EXPECTED TO MOVE BACK IN BY LATE AFTERNOON.
MVFR TO IFR CONDITIONS WILL PREVAIL TODAY WITH AREAS OF LIFR IN
THE HEAVIER SNOW BANDS. THE MOUNTAINS WILL BE OBSCURED THROUGHOUT
THE DAY. HOOLEY
&&
.PRELIMINARY POINT TEMP/POPS...
TDY TUE WED THU FRI SAT SUN
-------------------------------------------------------
BIL 035 009/012 000/027 018/024 004/015 009/023 014/028
+/S +9/S 71/B 01/B 22/J 22/J 21/B
LVM 040 023/029 010/043 026/034 014/029 019/034 021/036
9/O 97/S 51/B 01/B 12/J 22/J 21/B
HDN 028 007/016 904/023 013/025 000/018 006/023 008/028
+/S +9/S 71/B 01/B 21/E 22/J 11/B
MLS 015 904/009 915/017 010/017 907/008 902/017 002/021
9/S 47/S 31/B 12/J 11/B 21/B 11/B
4BQ 029 003/012 909/023 015/022 902/014 005/022 007/024
+/S 67/S 51/B 02/J 11/B 21/B 11/B
BHK 014 904/007 916/015 009/015 905/006 901/016 002/019
8/S 25/S 20/B 12/J 11/B 22/J 11/B
SHR 035 011/020 001/030 021/030 003/021 012/029 011/030
+/O 97/S 61/B 01/B 12/J 22/J 11/B
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...WINTER WEATHER ADVISORY IN EFFECT UNTIL 6 AM MST WEDNESDAY
FOR ZONES 28-31>34-36-37-39-41-42-65.
WINTER STORM WARNING IN EFFECT UNTIL 6 AM MST WEDNESDAY FOR
ZONES 29-30-35-38-40-57-58-63-67-68.
WINTER WEATHER ADVISORY IN EFFECT UNTIL 6 AM MST TUESDAY FOR
ZONES 56-66.
WY...WINTER STORM WARNING IN EFFECT UNTIL 6 AM MST WEDNESDAY FOR
ZONE 98.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
910 AM MST MON JAN 5 2015
.UPDATE...
THE MAIN FORECAST CHANGE THIS MORNING WAS TO LOWER SNOW TOTALS FOR
TODAY OVER SOUTH CENTRAL MT...ESPECIALLY AROUND BILLINGS. THE LOW-
LEVEL DOWNSLOPE FLOW ON THE SOUTH SIDE OF A SURFACE LOW LOCATED IN
CENTRAL MT NEAR LEWISTOWN AS OF 16 UTC IS INHIBITING SNOWFALL THUS
FAR THIS MORNING...AND THIS SITUATION WILL NOT CHANGE MUCH THROUGH
THE MID TO LATE AFTERNOON WHEN THE ARCTIC FRONT RUSHES SOUTH...AND
THE WINDS SWITCH BACK AROUND THE THE NORTHEAST IN BILLINGS. RECENT
HIGH-RESOLUTION MODEL GUIDANCE SUGGESTS THAT MIGHT NOT OCCUR UNTIL
VERY LATE AFTERNOON AND IN SOME OF THOSE SIMULATIONS NOT UNTIL THE
EARLY EVENING HOURS. SO...WE CUT BACK ON SNOWFALL TOTALS TODAY FOR
THE CITY AND SURROUNDING AREAS. THE ARCTIC FRONT JUST SURGED SOUTH
THROUGH GREAT FALLS AT 9 AM...WHICH TYPICALLY MEANS IT COULD REACH
BILLINGS BY 3 PM WITH SNOW THEN PICKING UP AFTER THAT TIME. WE ARE
STILL CARRYING ABOUT 2 INCHES TOTAL FOR TODAY IN BILLINGS...BUT IT
LOOKS LIKE IF WE GET THAT MUCH IT WILL BE MAINLY IN THE AFTERNOON.
IN CONTRAST...SNOW IS FALLING LIKE EXPECTED IN SOUTHEASTERN MT AND
VISIBILITY IS REDUCED TO 1/2SM IN MILES CITY AND BAKER AT THE MID-
MORNING HOUR. WE STILL EXPECT 3 TO 6 INCHES OF SNOW IN TOTAL TODAY
OVER SOUTHEASTERN MT.
WE ARE CHOOSING TO LEAVE THE HIGH WIND WARNING UP AT LIVINGSTON AT
THIS POINT GIVEN TRAVEL IMPACTS THERE...EVEN THOUGH WINDS ARE THUS
FAR NOT NOT AS STRONG AS EXPECTED. WE WILL REVISIT THAT DURING THE
LATE MORNING HOURS...ALONG WITH THE REST OF THE FORECAST FOR TODAY
AND INTO TONIGHT...WHICH IS A VERY DIFFICULT ONE WHICH MAY REQUIRE
FURTHER ADJUSTMENTS. SCHULTZ
&&
.SHORT TERM...VALID FOR TDY AND TUE...
VERY COMPLEX AND DYNAMIC WEATHER PATTERN TODAY...AND ONE THAT
WILL BE VERY DIFFICULT TO PINPOINT EXACT RESULTS...EVEN THIS CLOSE
IN TIME. MODELS HAVE A GENERAL AGREEMENT ON THE PATTERN...BUT
DISPLAY SUBTLE DIFFERENCES THAT COULD HAVE MAJOR SNOW/COLD
IMPLICATIONS. WILL STAY WITH A CONSENSUS GFS/EC MIX AND KEEP THE
MAJORITY OF THE FORECAST IN TACT.
FOR TODAY...VERY IMPRESSIVE SURFACE PRESSURE FALLS WERE OCCURRING
OVER NORTHERN MONTANA...RIGHT ALONG THE CANADIAN BORDER. THIS WAS
IN RESPONSE TO 170KT JET MAX SLIDING INTO NORTHEAST MONTANA. THIS
SCENARIO WILL ALLOW A LEE TROUGH TO QUICKLY DEVELOP AND GENERATE
STRONG WINDS AT LIVINGSTON THIS MORNING. WINDS ALREADY INCREASING
WITH SOME GUSTS TO 50 MPH AT LIVINGSTON. SOME MODEL GUIDANCE HAS
BACKED OFF ON WARNING TYPE OF WINDS...WHILE OTHER HAVE NOT. WILL
KEEP WARNING GOING.
THE FORMATION OF A SURFACE LOW FROM THE PRESSURE FALLS OVER THE
NORTH WILL HAVE HUGE RAMIFICATIONS ON OUR FORECAST TODAY. A
FARTHER NORTHWARD DEVELOPING LOW WOULD ALLOW FOR MORE DOWNSLOPE
FLOW OVER SOUTH CENTRAL MONTANA. THIS WOULD PROVIDE A WARMER
MORNING AND PUSH SOME OF THE HEAVIER SNOW EASTWARD AWAY FROM
BILLINGS. A FARTHER SOUTH LOW WOULD BE COLDER AND BRING THE
HEAVIER SNOW SOUTH AND WEST INTO BILLINGS. RADAR IMAGERY WAS
FILLING IN OVER WESTERN AND CENTRAL ZONES THIS MORNING...BUT HAS
SHOWN A DOWNSLOPE SIGNATURE OVERNIGHT. LOOKS LIKE THE RADAR IS
FILLING IN SIMILARLY TO THE HRRR WHICH PUTS THE HEAVIEST SNOW
EAST OF BILLINGS THIS MORNING WITH LIGHTER SNOW OVER WESTERN
YELLOWSTONE COUNTY. WILL GO IN THAT DIRECTION AND LIGHTEN UP
MORNING SNOWFALL OVER BILLINGS. STRONG WARM AIR ADVECTION WILL
SPREAD HEAVIER SNOW EAST OF BILLINGS INTO SOUTHEAST MONTANA AND
ADVISORIES FOR THE EAST LOOK GOOD.
ONCE THE SURFACE LOW DROPS INTO NORTHEAST WYOMING...THE
REINFORCING ARCTIC SURGE WILL DRIVE BACK IN WITH FALLING
TEMPERATURES IN THE AFTERNOON AND SNOW DEVELOPING. THIS IS THE
PERIOD OF HEAVIEST SNOW FOR BILLINGS...THIS AFTERNOON AND EVENING.
ARCTIC SHOULD GET INTO WESTERN ZONES TOO AND THE FOOTHILLS WILL
RECEIVE STRONG UPSLOPE FLOW THIS AFTERNOON AND TONIGHT. WILL ISSUE
A WINTER WEATHER ADVISORY FOR THE BEARTOOTH AND RED LODGE
FOOTHILLS FOR THIS TIME PERIOD. LIVINGSTON WILL BE A CHALLENGE
TODAY BECAUSE WARMER AIR WILL KEEP ACCUMULATIONS DOWN...BUT
BLOWING SNOW WILL BE AN ISSUE THIS MORNING. ALSO...BELIEVE THE
ARCTIC WILL SURGE BACK IN THERE LATE THIS AFTERNOON. LIVINGSTON
COULD GET WARNING AMOUNTS AS INSTABILITY WAS DECENT WITH
850-500MB LAPSE RATES APPROACHING 6C. WILL NEED TO BE WATCHED.
ARCTIC BOUNDARY HANGS UP OVER WESTERN ZONES TONIGHT AND WILL GET
AN OVER RUNNING SNOWFALL FOR TONIGHT THROUGH TUESDAY NIGHT. MODELS
KEEP THE FOOTHILLS OUT OF THE BEST OVER RUNNING WITH 700MB WINDS
REMAINING OUT OF THE NORTHWEST. THEREFORE WILL LIMIT THE
ADVISORIES OF NYE AND RED LODGE TO TODAY AND TONIGHT. SHOULD SEE 2
TO 4 INCH SNOW TOTALS EACH 12 HOURS THROUGH TUESDAY NIGHT OVER THE
REST OF THE FORECAST AREA. THE SNOW WILL COME TO AN END LATE
TUESDAY NIGHT. TWH
.LONG TERM...VALID FOR WED...THU...FRI...SAT...SUN...
FOR THE EXTENDED...MODELS CONTINUE TO SHOW THE REPRIEVE FROM THE
SNOWFALL WEDNESDAY. THE RIDGE ALONG THE WEST COAST WILL PUSH
EAST...MOVING THE ARCTIC AIR OUT OF THE AREA. TEMPERATURES WILL
RETURN MORE NORMAL VALUES...THOUGH THE EASTERN PLAINS MAY NOT HAVE
AS MUCH OF A RECOVERY.
THURSDAY ANOTHER SHORTWAVE WILL MOVE THROUGH THE NORTHWEST FLOW.
THIS WILL PROVIDE JUST ENOUGH INSTABILITY THAT MORE COLD AND SOME
LIGHT SNOW WILL MOVE BACK INTO THE AREA. FORCING IS VERY WEAK
WITH THIS...SO CONTINUE TO EXPECT MUCH LIGHTER SNOWFALL
ACCUMULATIONS. ANOTHER WEAK WAVE WILL MOVE THROUGH SUNDAY GIVING
THE AREA ANOTHER SHOT AT SOME LIGHT SNOW. AGAIN NOT MUCH FORCING
WITH THIS SO AMOUNTS WILL BE MUCH LIGHTER. TEMPERATURES WILL BE
SLIGHTLY BELOW NORMAL GOING THROUGH THE WEEKEND. THERE IS SUBTLE
TIMING DIFFERENCES BETWEEN THE MODELS...SO CURRENTLY GOING WITH A
BLEND.
ONE CAVEAT WITH TEMPERATURES THROUGH THE EXTENDED WILL BE HOW
MUCH SNOW PACK IS ON THE GROUND. REIMER
&&
.AVIATION...
STRONG WIND GUSTS AROUND 45 KTS WILL CONTINUE IN THE KLVM AREA
THROUGH THE REMAINDER OF THE MORNING RESULTING IN REDUCED
VISIBILITIES DUE TO BLOWING SNOW. AREAS OF LIGHT TO MODERATE SNOW
WILL CONTINUE ACROSS THE ENTIRE AREA TODAY. THE KBIL AREA MAY
CONTINUE TO SEE A BREAK IN THE SNOW THROUGH MOST OF THE DAY BUT
THE HEAVIER SNOW IS EXPECTED TO MOVE BACK IN BY LATE AFTERNOON.
MVFR TO IFR CONDITIONS WILL PREVAIL TODAY WITH AREAS OF LIFR IN
THE HEAVIER SNOW BANDS. THE MOUNTAINS WILL BE OBSCURED THROUGHOUT
THE DAY. HOOLEY
&&
.PRELIMINARY POINT TEMP/POPS...
TDY TUE WED THU FRI SAT SUN
-------------------------------------------------------
BIL 028 009/012 000/027 018/024 004/015 009/023 014/028
+/S +9/S 71/B 01/B 22/J 22/J 21/B
LVM 040 023/029 010/043 026/034 014/029 019/034 021/036
9/O 97/S 51/B 01/B 12/J 22/J 21/B
HDN 028 007/016 904/023 013/025 000/018 006/023 008/028
+/S +9/S 71/B 01/B 21/E 22/J 11/B
MLS 015 904/009 915/017 010/017 907/008 902/017 002/021
+/S 47/S 31/B 12/J 11/B 21/B 11/B
4BQ 029 003/012 909/023 015/022 902/014 005/022 007/024
+/S 67/S 51/B 02/J 11/B 21/B 11/B
BHK 014 904/007 916/015 009/015 905/006 901/016 002/019
+/S 25/S 20/B 12/J 11/B 22/J 11/B
SHR 035 011/020 001/030 021/030 003/021 012/029 011/030
+/O 97/S 61/B 01/B 12/J 22/J 11/B
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...WINTER WEATHER ADVISORY IN EFFECT UNTIL 6 AM MST WEDNESDAY
FOR ZONES 28-31>34-36-37-39-41-42-65.
WINTER STORM WARNING IN EFFECT UNTIL 6 AM MST WEDNESDAY FOR
ZONES 29-30-35-38-40-57-58-63-67-68.
WINTER WEATHER ADVISORY IN EFFECT UNTIL 6 AM MST TUESDAY FOR
ZONES 56-66.
HIGH WIND WARNING IN EFFECT UNTIL NOON MST TODAY FOR ZONES
65-66.
WY...WINTER STORM WARNING IN EFFECT UNTIL 6 AM MST WEDNESDAY FOR
ZONE 98.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
344 PM CST MON JAN 5 2015
.SYNOPSIS...
ISSUED AT 342 PM CST MON JAN 5 2015
WARM FRONT ALOFT MOVING EAST ACROSS THE CWA THIS AFTERNOON. HIGHER
TERRAIN TO THE WEST HELPING MIX THE WARMER AIR ALOFT TO THE
SFC...BFF AND IBM IN THE PANHANDLE ARE IN THE 40S. MEANWHILE FURTHER
EAST THE SNOWPACK AND LOWER LEVELS OF MOST OF THE CWA RESULTING IN
LESS MIXING AND TEMPS IN THE TEENS AND 20S. DISTURBANCE THAT BROUGHT
SNOW TO N CENTRAL MOST OF THE DAY HAS DRIFTED EAST WITH MOST REPORTS
NOW ONLY SEEING FLURRIES IF ANYTHING. A SECONDARY DISTURBANCE IS
CROSSING THE BLACK HILLS...ALTHOUGH THE TEMP THERE WAS ABOVE
FREEZING /AS WAS THE TEMPS OF THE LOWER LEVELS/ SO PRECIP WAS LIQUID
EARLIER. THE NEXT COLD FRONT IS STARTING TO PUSH SE ACROSS WESTERN S
DAKOTA AND RAP HAS COOLED OFF WITH THE 21Z OB HAVING CHANGE BACK TO
SNOW.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 342 PM CST MON JAN 5 2015
ANOTHER COMPLICATED FORECAST WITH SEVERAL CONCERNS OVER THE NEXT 24
HOURS. FIRST OFF IS EVENING TEMPERATURES. 850 MB TEMPS ACROSS MUCH
OF THE CWA IN POSITIVE C TERRITORY...HOWEVER MIXING IS LIMITED DO TO
CLOUDS...SNOW PACK...AND JANUARY SUN ANGLE. A COLD FRONT IS
BEGINNING TO PUSH SOUTH ACROSS THE AREA...AND WILL CONTINUE TO DO SO
OVERNIGHT. ALONG AND BEHIND THE FRONT WINDS SWITCH TO THE NORTHWEST
AND ARE GUSTY. THIS GUSTINESS ALONG THE FRONT MAY ACTUALLY HELP
CAUSE A BUMP IN TEMPS. WITH SUCH WARM 850 MB TEMPS...THE MIXING MAY
CAUSE TEMPS TO SURGE BRIEFLY INTO THE 30S. THIS IS EXPECTED ACROSS
THE HIGHER TERRAIN OF THE WESTERN CWA...MORE UNCERTAINTY ACROSS THE
CENTRAL AND EAST.
MEANWHILE AN UPPER LEVEL DISTURBANCE SLIDES FROM THE BLACK HILLS TO
THE SE. A FEW RADAR RETURNS ACROSS SW SOUTH DAKOTA AND INTO PARTS OF
NORTHERN NEB. THE WARM LOWER LEVEL IS ALSO DRY AND EXPECT LITTLE
MOISTURE TO MAKE IT TO THE GROUND. THAT SAID...CAN NOT RULE OUT A
FEW ISOLATED FLURRIES THIS EVENING. THE NW FLOW AROUND THE HILLS
CONVERGES NEAR PINE RIDGE AND COULD SEE SOME LIGHT SNOW THERE AS
WELL. AGAIN SOME CONCERN FOR THE DRY LOWER LEVELS LIMITING ANYTHING
REACHING THE GROUND AND POPS ARE LOW.
OVERNIGHT TEMPERATURES DO FINALLY DROP AFTER THE FRONT IS SOUTH OF
THE AREA...ALTHOUGH CLOUDS LINGER AS A BLANKET AND LIMIT COOLING.
LOWS GENERALLY BOTTOM OUT IN THE SINGLE DIGITS ABOVE ZERO TO THE
TEENS.
TOMORROW ARRIVES THE NEXT SHORT WAVE IN THE FAST MOVING NW FLOW
REGIME. NORTHERN NEBRASKA HAS THE BEST CHANCE FOR SNOWFALL. LIFT IS
MARGINAL IN THE NARROW DENDRITIC GROWTH ZONE...AND SHOULD COMBINE
WITH THE FAST MOVING SYSTEM TO LIMIT SNOW ACCUMULATION TO LESS THAN
AN INCH DURING THE DAYTIME. HIGHS STRUGGLE INTO THE TEENS DUE TO THE
CLOUDS/LIGHT SNOW ACROSS NORTHERN NEB...ESPECIALLY NORTH CENTRAL.
WARMER IN THE SW...MID 20S TO NEAR FREEZING...ALTHOUGH THIS MAY BE
OPTIMISTIC DUE TO THE SNOW PACK.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 342 PM CST MON JAN 5 2015
THE NEXT AIR MASS WILL MOVE ONTO THE CENTRAL PLAINS TUESDAY NIGHT
AND WEDNESDAY. THE TEMPERATURE OF THE AIR IS EXPECTED TO BE 5-15F
COLDER IN EASTERN NEBRASKA THAN IN CENTRAL AND WESTERN NEBRASKA. THE
COLDER TEMPERATURES IN NORTH CENTRAL NEBRASKA ARE LOCATED WHERE THE
STRONGEST WIND IS EXPECTED. THEREFORE...WIND CHILLS OF -20F TO -25F
APPEAR TO BE A GOOD BET...POSSIBLY EVEN NEAR -30F FOR NORTH CENTRAL
NEBRASKA NEAR THE NIOBRARA.
ANOTHER FORECAST ISSUE IS THE POTENTIAL FOR LIGHT SNOW WITH THE
ARCTIC FRONT. WITH THE AIR MASS SO STRONG...THE SYSTEM-RELATIVE LIFT
IS LIKELY TO BE SIGNIFICANT IN THE 280-300K LAYER WITH THE BEST LIFT
IN NORTHERN NEBRASKA. A CROSS SECTION OF THE AGEOSTROPHIC VERTICAL
CIRCULATION THROUGH NORTH CENTRAL-SOUTHWEST NEBRASKA INDICATES THAT
THE THERE DOES NOT APPEAR TO BE LOT OF ENHANCEMENT FROM
FRONTOGENESIS OR INSTABILITY. WITH THE LOW PRECIPITATION AMOUNTS
INDICATED IN THE MODELS...CONFIDENCE IS NOT HIGH AND WE WILL KEEP
THE PROBABILITY FAIRLY LOW.
AS LOW LEVEL FLOW RETURNS TO A SOUTHERLY DIRECTION...HIGHER
TEMPERATURES CAN BE EXPECTED THURSDAY.
A FRONT SAGS BACK TO THE SOUTHWEST AS ANOTHER ARCTIC AIRMASS GOES
THROUGH CENTRAL AND EASTERN NEBRASKA. IN FACT...WITH ARCTIC AIR
MASSES GOING THROUGH EVERY TWO DAYS...TEMPERATURES WILL VARY WIDELY
FROM ONE DAY TO THE NEXT. AS THE FRONTS GO THROUGH...THERE IS A
POSSIBILITY OF PRECIPITATION BUT THE CHANCES...IF ANY...WILL BE LOW.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1215 PM CST MON JAN 5 2015
SNOW IS DIMINISHING ACROSS N CENTRAL NEB...INCLUDING VALENTINE...AND
ONLY SEE ANOTHER HOUR OR TWO OF LIGHT SNOWFALL POSSIBLE AT THE
TERMINAL. BRIEF MVFR VISIBILITIES ARE POSSIBLE OTHERWISE TREND TO
VFR OVERCAST SKIES EXPECTED. SOUTHERLY WINDS GUSTING TO 20 TO 30
KTS THIS AFTERNOON...BECOME NORTHWESTERLY AND CONTINUED GUSTY BEHIND
THE COLD FRONT WHICH PUSHES SOUTHEAST ACROSS THE AREA. ALSO
ASSOCIATED WITH AND BEHIND THE FRONT WILL LIKELY BE LOWERING MVFR
CIGS. BY EARLY MORNING...WINDS WILL BECOME LIGHT AND VARIABLE.
ALSO EXPECT THE CIGS TO BE IMPROVING TO VFR ACROSS NORTHERN
NEBRASKA.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...MASEK
SHORT TERM...MASEK
LONG TERM...SPRINGER
AVIATION...MASEK
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
642 PM EST TUE JAN 6 2015
.SYNOPSIS...
AN ARCTIC COLD FRONT WILL SWING SOUTH ACROSS THE AREA OVERNIGHT AS
LOW PRESSURE MOVES ACROSS SOUTHERN ONTARIO INTO QUEBEC TONIGHT.
HIGH PRESSURE WILL BRIEFLY RIDGE INTO THE AREA FROM THE OHIO RIVER
VALLEY ON THURSDAY BUT ANOTHER ARCTIC BOUNDARY WILL ARRIVE BY
FRIDAY MORNING.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
LAKE EFFECT SNOW BANDS HAVE BEEN CLIPPING THE SHORELINE FOR MOST
OF THE DAY SO STARTED THE LAKE EFFECT SNOW WARNING NOW FOR THE
LAKESHORE ZONES. BOTH THE HRRR AND 1000-850MB OMEGA BECOME FAIRLY
ENERGETIC AHEAD OF THE FRONT IN THE WESTERLY FLOW THIS EVENING.
SNOW SHOWERS ARE EXPECTED TO CONTINUE AT TIMES...THROUGH THE EARLY
EVENING AND THEN BECOME HEAVY IMMEDIATELY AHEAD OF THE FRONT. THIS
BAND WILL COME CRASHING ONSHORE WITH THE PASSAGE OF THE ARCTIC
FRONT OVERNIGHT WITH SNOW SHOWERS SPREADING INLAND. INLAND
AREAS...ESPECIALLY THOSE IN THE SECONDARY SNOW BELT WILL NOT SEE
MUCH SNOW UNTIL THE FRONT PASSES SO DELAYED THE START TIME ON THE
LAKE EFFECT SNOW ADVISORY UNTIL 3 AM. HEAVY BURST OF SNOW EXPECTED
TO IMPACT THE METRO CLEVELAND AREA FOR THE MORNING COMMUTE MAKING
TRAVEL DIFFICULT AND SLOW.
WIND CHILL ADVISORIES HAVE BEEN ISSUED FOR ALL AREAS OUTSIDE OF
THE LAKE EFFECT SNOW HEADLINES. TEMPERATURES WILL FALL TO 5-7
DEGREES OUTSIDE OF THE SNOWBELT AND COMBINE WITH WINDS OF 15 TO 20
MPH TO PRODUCE WIND CHILLS OF -10 TO -15. THIS IS ON THE LOWER END
OF THE ADVISORY SPECTRUM...WITH THE COLDEST VALUES EXPECTED
WEDNESDAY NIGHT INTO THURSDAY.
NO CHANGES WITH THIS EARLY EVENING UPDATE.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY/...
LAKE EFFECT SNOW EXPECTED TO BE HEAVY AT TIMES THROUGH AT LEAST
THE MORNING WITH EXTREME LAPSE RATES WITHIN THE FRIGID AIRMASS
COMING OFF OF LAKE ERIE. SOME DISRUPTION TO THE LAKE EFFECT WILL
OCCUR WITH THE PASSAGE OF THE FRONT BUT EXPECT BANDS TO DEVELOP
QUICKLY AS THE NORTHWEST FLOW SETS UP. THE MAIN FEATURE TO WATCH
ON WEDNESDAY WILL BE A DOMINANT LAKE EFFECT SNOW BAND COMING OFF
LAKE HURON. TODAYS HIGH RESOLUTION MODELS ARE STILL EXCITED ABOUT
THIS FEATURE BUT HAVE SHIFTED IT A LITTLE FARTHER EAST INTO ERIE
AND CRAWFORD PA. SNOWFALL RATES OF TWO INCHES PER HOUR WILL BE
POSSIBLE WHERE THIS BAND SETS UP.
THE UNCERTAINTY FOR THE FORECAST FOR TOMORROW LIES IN HOW
WIDESPREAD SNOW SHOWERS WILL BE THROUGH THE AFTERNOON AS THE
AIRMASS ATTEMPTS TO DRY OUT. MODELS SOUNDING INDICATE 800 J/KG OF
LAKE INDUCED CAPE COMBINED WITH EQUILIBRIUM LEVELS HOLDING UP
AROUND 10K FEET. THE FORECAST CONTINUES SNOW THROUGH THE AFTERNOON
BUT IT IS POSSIBLE THAT SNOW SHOWERS START TO BREAK UP AND
DECREASE OUTSIDE OF THE DOMINANT BAND IF WE DRY OUT ENOUGH.
BLOWING AND DRIFTING OF SNOW WILL BE AN ADDITIONAL AGGRAVATION ON
WEDNESDAY.
THE FLOW START TO BACK DURING THE EVENING ON WEDNESDAY WITH THE
TREND TO BE FOR SNOW SHOWERS TO BECOME CONFINED TO THE SNOWBELT
AGAIN. WE WILL HAVE TO WATCH FOR ANY WESTERLY BANDS THAT TRY TO
DEVELOP WHERE LOW LEVEL CONVERGENCE PEAKS.
THE WIND CHILL ADVISORY CONTINUES FOR PORTIONS OF NORTH WEST OHIO
THROUGH WEDNESDAY NIGHT WHILE A WATCH HAS BEEN ISSUED FOR AN AREA
OF WEST CENTRAL OHIO FROM FINDLAY TO MANSFIELD. AS TEMPERATURES
FALL TO 5 TO 10 BELOW IN THIS AREA AND COMBINE WITH THE
WIND...THIS AREA STANDS THE BEST CHANCE OF SEEING WIND CHILL
VALUES DROP BELOW -25 WHICH IS WHAT IS NEEDED FOR A WIND CHILL
WARNING. THE WIND CHILL ADVISORY WILL ALSO NEED TO BE EXPANDED TO
THE LAKESHORE COUNTIES FOR WEDNESDAY NIGHT.
CONDITIONS DRY OUT ON THURSDAY AS HIGH PRESSURE BUILDS EAST ACROSS
THE OHIO VALLEY. BY THURSDAY NIGHT THE MODELS PROG ANOTHER
CLIPPER SYSTEM TO TRACK TO THE NORTH OF LAKE ERIE. THE BEST CHANCE
FOR SNOW WILL BE ACROSS THE NORTHERN COUNTIES THOUGH ALL AREAS
COULD SEE SOME LIGHT SNOW INTO EARLY FRIDAY. THERE WILL BE ANOTHER
REINFORCING SHOT OF ARCTIC AIR BEHIND THIS SYSTEM. THE BEST
CHANCES FOR SNOW FRIDAY NIGHT WILL BE ALONG THE SNOWBELT AS WINDS
SHIFT TO THE WEST AND H850 TEMPS DROP OFF TO AROUND -20C.
ELSEWHERE THE SNOW SHOULD DISSIPATE.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
THE LONG TERM BEGINS ON SATURDAY WITH MODELS SHOWING HIGH PRESSURE
OVER THE OHIO VALLEY ALTHOUGH A CONTINUED WEST FLOW OVER THE LAKE
ONSHORE IN THE SNOWBELT. WILL CONTINUE WITH HIGH CHANCE POPS FOR THE
MORNING AND DROP BACK TO 30-40% FOR THE AFTERNOON. BY SUNDAY MODELS
TAKE A DIVERGENT PATH WITH THE ECMWF WARMER AND WETTER WHILE THE GFS
SHOWS COLDER AND MUCH DRIER. FOR NOW FOLLOWED WPS GUIDANCE WHICH
SHOWS FAIRLY DRY CONDITIONS AND MODERATING TEMPS IN THE UPPER 20S
AND LOWER 30S SUNDAY AND BEYOND.
&&
.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
TRIED TO FINE TUNE AND SIMPLIFY THE TAFS. STILL EXPECTING A PRETTY
GOOD LAKE EFFECT EVENT DURING THE PERIOD. THE ACTIVITY AT KERI MAY
DIMINISH SOME THIS EVENING AS SW FLOW PERSISTS. A TROUGH IS STILL
ON TRACK TO CROSS THE AREA LATE TONIGHT. THE FLOW WILL BECOME NW
BEHIND THIS FEATURE. EXPECT THE LAKE EFFECT ACTIVITY TO INCREASE
AT THAT TIME. ALL OF THE EASTERN TAF SITES WILL SEE MVFR SNOW WITH
PERIODS OF IFR FROM LATE TONIGHT THROUGH TOMORROW AFTERNOON. LOT`S
OF UNCERTAINTY GIVEN THE NATURE OF THE LAKE EFFECT. EXPECT
CONDITIONS TO VARY QUITE A BIT WITH PERIODS OF MODERATE TO HEAVY
SNOW. WINDS WILL GRADUALLY INCREASE DURING THE PERIOD WITH GUSTS
TO 25 KNOTS ALL AREAS BY MORNING WITH GUSTS TO 30 KNOTS POSSIBLE
DURING THE DAY. KFDY AND KTOL SHOULD BE VFR MUCH OF THE PERIOD BUT
SOME PERIODS OF MVFR SNOW ARE POSSIBLE...ESPECIALLY AT KTOL LATE
TONIGHT.
.OUTLOOK...NON VFR WEDNESDAY NIGHT THROUGH THURSDAY IN NORTHEAST
OHIO AND NWRN PA WITH LAKE EFFECT SNOW.
&&
.MARINE...
THE WESTERN BASIN OF LAKE ERIE IS NOW MOSTLY ICE COVERED. CANCELLED
THE SMALL CRAFT THERE DUE TO THE ICE. CONTINUED THE SMALL CRAFT
ADVISORY WITHOUT CHANGE. WILL ISSUE A HEAVY FREEZING SPRAY WARNING
BEGINNING AT 3AM TONIGHT AND LASTING THROUGH 4PM FRIDAY AFTERNOON.
WEST FLOW ON THE LAKE WILL INCREASE TO 30 KNOTS EARLY TONIGHT AS
HIGH PRESSURE DROPS ACROSS THE NORTHERN PLAINS AND LOW PRESSURE
MOVES NORTHEAST OF THE LAKE. WINDS WILL TURN NORTHWEST AS THE
ASSOCIATED ARCTIC COLD FRONT DROP ACROSS THE LAKE LATE TONIGHT.
EXPECT MODERATE FREEZING SPRAY THIS EVENING INTO THE FIRST HALF OF
THE NIGHT. FREEZING SPRAY WILL TURN HEAVY AS TEMPS FALL. ALSO LAKE
EFFECT SNOWFALL WILL ALSO TURN HEAVY EAST HALF TONIGHT AND CONTINUE
THROUGH WEDNESDAY NIGHT REDUCING VISIBILITIES TO UNDER A MILE. WINDS
WILL TURN WEST AND SOUTHWEST THURSDAY AND FRIDAY BUT HEAVY FREEZING
SPRAY WILL REMAIN LIKELY THROUGH AT LEAST FRIDAY AFTERNOON. SATURDAY
HIGH PRESSURE WILL MOVE THROUGH THE OHIO VALLEY DECREASING WINDS AND
WAVES.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...LAKE EFFECT SNOW WARNING UNTIL 4 AM EST THURSDAY FOR OHZ012-
089.
LAKE EFFECT SNOW WARNING UNTIL 4 AM EST THURSDAY FOR OHZ013-
014.
LAKE EFFECT SNOW ADVISORY FROM 3 AM TO 9 PM EST WEDNESDAY FOR
OHZ010-011-020>023.
WIND CHILL ADVISORY FROM 10 PM THIS EVENING TO 1 PM EST
THURSDAY FOR OHZ003-006>009-018-019-031>033-038.
WIND CHILL WATCH FROM WEDNESDAY EVENING THROUGH THURSDAY
AFTERNOON FOR OHZ017-027>030-036-037-047.
WIND CHILL ADVISORY FROM 10 PM THIS EVENING TO 10 PM EST
WEDNESDAY FOR OHZ017-027>030-036-037-047.
PA...LAKE EFFECT SNOW WARNING UNTIL 4 AM EST THURSDAY FOR PAZ001.
LAKE EFFECT SNOW WARNING UNTIL 4 AM EST THURSDAY FOR PAZ002-
003.
MARINE...HEAVY FREEZING SPRAY WARNING FROM 3 AM WEDNESDAY TO 4 PM EST
FRIDAY FOR LEZ061-144>149-164>169.
SMALL CRAFT ADVISORY UNTIL 4 AM EST SATURDAY FOR LEZ144>149.
&&
$$
SYNOPSIS...KEC
NEAR TERM...KEC/OUDEMAN
SHORT TERM...KEC
LONG TERM...TK
AVIATION...KUBINA
MARINE...TK
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
628 PM EST TUE JAN 6 2015
.SYNOPSIS...
AN ARCTIC COLD FRONT WILL SWING SOUTH ACROSS THE AREA OVERNIGHT AS
LOW PRESSURE MOVES ACROSS SOUTHERN ONTARIO INTO QUEBEC TONIGHT.
HIGH PRESSURE WILL BRIEFLY RIDGE INTO THE AREA FROM THE OHIO RIVER
VALLEY ON THURSDAY BUT ANOTHER ARCTIC BOUNDARY WILL ARRIVE BY
FRIDAY MORNING.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
LAKE EFFECT SNOW BANDS HAVE BEEN CLIPPING THE SHORELINE FOR MOST
OF THE DAY SO STARTED THE LAKE EFFECT SNOW WARNING NOW FOR THE
LAKESHORE ZONES. BOTH THE HRRR AND 1000-850MB OMEGA BECOME FAIRLY
ENERGETIC AHEAD OF THE FRONT IN THE WESTERLY FLOW THIS EVENING.
SNOW SHOWERS ARE EXPECTED TO CONTINUE AT TIMES...THROUGH THE EARLY
EVENING AND THEN BECOME HEAVY IMMEDIATELY AHEAD OF THE FRONT. THIS
BAND WILL COME CRASHING ONSHORE WITH THE PASSAGE OF THE ARCTIC
FRONT OVERNIGHT WITH SNOW SHOWERS SPREADING INLAND. INLAND
AREAS...ESPECIALLY THOSE IN THE SECONDARY SNOW BELT WILL NOT SEE
MUCH SNOW UNTIL THE FRONT PASSES SO DELAYED THE START TIME ON THE
LAKE EFFECT SNOW ADVISORY UNTIL 3 AM. HEAVY BURST OF SNOW EXPECTED
TO IMPACT THE METRO CLEVELAND AREA FOR THE MORNING COMMUTE MAKING
TRAVEL DIFFICULT AND SLOW.
WIND CHILL ADVISORIES HAVE BEEN ISSUED FOR ALL AREAS OUTSIDE OF
THE LAKE EFFECT SNOW HEADLINES. TEMPERATURES WILL FALL TO 5-7
DEGREES OUTSIDE OF THE SNOWBELT AND COMBINE WITH WINDS OF 15 TO 20
MPH TO PRODUCE WIND CHILLS OF -10 TO -15. THIS IS ON THE LOWER END
OF THE ADVISORY SPECTRUM...WITH THE COLDEST VALUES EXPECTED
WEDNESDAY NIGHT INTO THURSDAY.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY/...
LAKE EFFECT SNOW EXPECTED TO BE HEAVY AT TIMES THROUGH AT LEAST
THE MORNING WITH EXTREME LAPSE RATES WITHIN THE FRIGID AIRMASS
COMING OFF OF LAKE ERIE. SOME DISRUPTION TO THE LAKE EFFECT WILL
OCCUR WITH THE PASSAGE OF THE FRONT BUT EXPECT BANDS TO DEVELOP
QUICKLY AS THE NORTHWEST FLOW SETS UP. THE MAIN FEATURE TO WATCH
ON WEDNESDAY WILL BE A DOMINANT LAKE EFFECT SNOW BAND COMING OFF
LAKE HURON. TODAYS HIGH RESOLUTION MODELS ARE STILL EXCITED ABOUT
THIS FEATURE BUT HAVE SHIFTED IT A LITTLE FARTHER EAST INTO ERIE
AND CRAWFORD PA. SNOWFALL RATES OF TWO INCHES PER HOUR WILL BE
POSSIBLE WHERE THIS BAND SETS UP.
THE UNCERTAINTY FOR THE FORECAST FOR TOMORROW LIES IN HOW
WIDESPREAD SNOW SHOWERS WILL BE THROUGH THE AFTERNOON AS THE
AIRMASS ATTEMPTS TO DRY OUT. MODELS SOUNDING INDICATE 800 J/KG OF
LAKE INDUCED CAPE COMBINED WITH EQUILIBRIUM LEVELS HOLDING UP
AROUND 10K FEET. THE FORECAST CONTINUES SNOW THROUGH THE AFTERNOON
BUT IT IS POSSIBLE THAT SNOW SHOWERS START TO BREAK UP AND
DECREASE OUTSIDE OF THE DOMINANT BAND IF WE DRY OUT ENOUGH.
BLOWING AND DRIFTING OF SNOW WILL BE AN ADDITIONAL AGGRAVATION ON
WEDNESDAY.
THE FLOW START TO BACK DURING THE EVENING ON WEDNESDAY WITH THE
TREND TO BE FOR SNOW SHOWERS TO BECOME CONFINED TO THE SNOWBELT
AGAIN. WE WILL HAVE TO WATCH FOR ANY WESTERLY BANDS THAT TRY TO
DEVELOP WHERE LOW LEVEL CONVERGENCE PEAKS.
THE WIND CHILL ADVISORY CONTINUES FOR PORTIONS OF NORTH WEST OHIO
THROUGH WEDNESDAY NIGHT WHILE A WATCH HAS BEEN ISSUED FOR AN AREA
OF WEST CENTRAL OHIO FROM FINDLAY TO MANSFIELD. AS TEMPERATURES
FALL TO 5 TO 10 BELOW IN THIS AREA AND COMBINE WITH THE
WIND...THIS AREA STANDS THE BEST CHANCE OF SEEING WIND CHILL
VALUES DROP BELOW -25 WHICH IS WHAT IS NEEDED FOR A WIND CHILL
WARNING. THE WIND CHILL ADVISORY WILL ALSO NEED TO BE EXPANDED TO
THE LAKESHORE COUNTIES FOR WEDNESDAY NIGHT.
CONDITIONS DRY OUT ON THURSDAY AS HIGH PRESSURE BUILDS EAST ACROSS
THE OHIO VALLEY. BY THURSDAY NIGHT THE MODELS PROG ANOTHER
CLIPPER SYSTEM TO TRACK TO THE NORTH OF LAKE ERIE. THE BEST CHANCE
FOR SNOW WILL BE ACROSS THE NORTHERN COUNTIES THOUGH ALL AREAS
COULD SEE SOME LIGHT SNOW INTO EARLY FRIDAY. THERE WILL BE ANOTHER
REINFORCING SHOT OF ARCTIC AIR BEHIND THIS SYSTEM. THE BEST
CHANCES FOR SNOW FRIDAY NIGHT WILL BE ALONG THE SNOWBELT AS WINDS
SHIFT TO THE WEST AND H850 TEMPS DROP OFF TO AROUND -20C.
ELSEWHERE THE SNOW SHOULD DISSIPATE.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
THE LONG TERM BEGINS ON SATURDAY WITH MODELS SHOWING HIGH PRESSURE
OVER THE OHIO VALLEY ALTHOUGH A CONTINUED WEST FLOW OVER THE LAKE
ONSHORE IN THE SNOWBELT. WILL CONTINUE WITH HIGH CHANCE POPS FOR THE
MORNING AND DROP BACK TO 30-40% FOR THE AFTERNOON. BY SUNDAY MODELS
TAKE A DIVERGENT PATH WITH THE ECMWF WARMER AND WETTER WHILE THE GFS
SHOWS COLDER AND MUCH DRIER. FOR NOW FOLLOWED WPS GUIDANCE WHICH
SHOWS FAIRLY DRY CONDITIONS AND MODERATING TEMPS IN THE UPPER 20S
AND LOWER 30S SUNDAY AND BEYOND.
&&
.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
TRIED TO FINE TUNE AND SIMPLIFY THE TAFS. STILL EXPECTING A PRETTY
GOOD LAKE EFFECT EVENT DURING THE PERIOD. THE ACTIVITY AT KERI MAY
DIMINISH SOME THIS EVENING AS SW FLOW PERSISTS. A TROUGH IS STILL
ON TRACK TO CROSS THE AREA LATE TONIGHT. THE FLOW WILL BECOME NW
BEHIND THIS FEATURE. EXPECT THE LAKE EFFECT ACTIVITY TO INCREASE
AT THAT TIME. ALL OF THE EASTERN TAF SITES WILL SEE MVFR SNOW WITH
PERIODS OF IFR FROM LATE TONIGHT THROUGH TOMORROW AFTERNOON. LOT`S
OF UNCERTAINTY GIVEN THE NATURE OF THE LAKE EFFECT. EXPECT
CONDITIONS TO VARY QUITE A BIT WITH PERIODS OF MODERATE TO HEAVY
SNOW. WINDS WILL GRADUALLY INCREASE DURING THE PERIOD WITH GUSTS
TO 25 KNOTS ALL AREAS BY MORNING WITH GUSTS TO 30 KNOTS POSSIBLE
DURING THE DAY. KFDY AND KTOL SHOULD BE VFR MUCH OF THE PERIOD BUT
SOME PERIODS OF MVFR SNOW ARE POSSIBLE...ESPECIALLY AT KTOL LATE
TONIGHT.
.OUTLOOK...NON VFR WEDNESDAY NIGHT THROUGH THURSDAY IN NORTHEAST
OHIO AND NWRN PA WITH LAKE EFFECT SNOW.
&&
.MARINE...
THE WESTERN BASIN OF LAKE ERIE IS NOW MOSTLY ICE COVERED. CANCELLED
THE SMALL CRAFT THERE DUE TO THE ICE. CONTINUED THE SMALL CRAFT
ADVISORY WITHOUT CHANGE. WILL ISSUE A HEAVY FREEZING SPRAY WARNING
BEGINNING AT 3AM TONIGHT AND LASTING THROUGH 4PM FRIDAY AFTERNOON.
WEST FLOW ON THE LAKE WILL INCREASE TO 30 KNOTS EARLY TONIGHT AS
HIGH PRESSURE DROPS ACROSS THE NORTHERN PLAINS AND LOW PRESSURE
MOVES NORTHEAST OF THE LAKE. WINDS WILL TURN NORTHWEST AS THE
ASSOCIATED ARCTIC COLD FRONT DROP ACROSS THE LAKE LATE TONIGHT.
EXPECT MODERATE FREEZING SPRAY THIS EVENING INTO THE FIRST HALF OF
THE NIGHT. FREEZING SPRAY WILL TURN HEAVY AS TEMPS FALL. ALSO LAKE
EFFECT SNOWFALL WILL ALSO TURN HEAVY EAST HALF TONIGHT AND CONTINUE
THROUGH WEDNESDAY NIGHT REDUCING VISIBILITIES TO UNDER A MILE. WINDS
WILL TURN WEST AND SOUTHWEST THURSDAY AND FRIDAY BUT HEAVY FREEZING
SPRAY WILL REMAIN LIKELY THROUGH AT LEAST FRIDAY AFTERNOON. SATURDAY
HIGH PRESSURE WILL MOVE THROUGH THE OHIO VALLEY DECREASING WINDS AND
WAVES.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...LAKE EFFECT SNOW WARNING UNTIL 4 AM EST THURSDAY FOR OHZ012-
089.
LAKE EFFECT SNOW WARNING UNTIL 4 AM EST THURSDAY FOR OHZ013-
014.
LAKE EFFECT SNOW ADVISORY FROM 3 AM TO 9 PM EST WEDNESDAY FOR
OHZ010-011-020>023.
WIND CHILL ADVISORY FROM 10 PM THIS EVENING TO 1 PM EST
THURSDAY FOR OHZ003-006>009-018-019-031>033-038.
WIND CHILL WATCH FROM WEDNESDAY EVENING THROUGH THURSDAY
AFTERNOON FOR OHZ017-027>030-036-037-047.
WIND CHILL ADVISORY FROM 10 PM THIS EVENING TO 10 PM EST
WEDNESDAY FOR OHZ017-027>030-036-037-047.
PA...LAKE EFFECT SNOW WARNING UNTIL 4 AM EST THURSDAY FOR PAZ001.
LAKE EFFECT SNOW WARNING UNTIL 4 AM EST THURSDAY FOR PAZ002-
003.
MARINE...HEAVY FREEZING SPRAY WARNING FROM 3 AM WEDNESDAY TO 4 PM EST
FRIDAY FOR LEZ061-144>149-164>169.
SMALL CRAFT ADVISORY UNTIL 4 AM EST SATURDAY FOR LEZ144>149.
&&
$$
SYNOPSIS...KEC
NEAR TERM...KEC
SHORT TERM...KEC
LONG TERM...TK
AVIATION...KUBINA
MARINE...TK
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
310 PM CST MON JAN 5 2015
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 310 PM CST MON JAN 5 2015
FORECAST PRETTY MUCH IN LINE WITH PREVIOUS THINKING AS A BROAD AREA
OF MODERATE TO OCCASIONALLY HEAVY SNOW IS PRESENTLY OCCURRING OVER
ALL BUT FAR SOUTH CENTRAL SOUTH DAKOTA THIS AFTERNOON. THIS IN
ASSOCIATION WITH AN INTENSIFYING 700 MB FRONT AND AN APPROACHING
UPPER LEVEL SHORTWAVE DROPPING INTO WESTERN NORTH DAKOTA/NORTH
CENTRAL SOUTH DAKOTA AT THIS TIME. CURRENT RADAR SHOWING ENHANCED
RETURNS THROUGH THE CENTRAL AND SOUTHERN INTERSTATE 29 CORRIDOR INTO
NORTHWESTERN IOWA...ALIGNED FAIRLY WELL WITH WHERE MODEL PROGGED
FRONTOGENESIS LOOKS TO BE STRONGEST. EXPECT ENHANCEMENT TO CONTINUE
THROUGH THE LATE AFTERNOON AS THE AFOREMENTIONED SHORTWAVE SLIDES
THROUGH OUR AREA. THE RAP DOES INDICATE SOME SLIGHT INSTABILITY
ABOVE THE FRONTAL CIRCULATION FOR LATE AFTERNOON...WHICH COULD
RESULT IN A NARROWER BAND OF HEAVIER SNOW THROUGH NORTHWESTERN IOWA
DURING THE LATE AFTERNOON...WHICH ALIGNS WELL WITH OUR CURRENT
SNOWFALL GRIDS. THIS IN COMBINATION WITH SNOW RATIOS IN THE RANGE OF
15 TO 25:1 IN A DEEPER DENDRITIC LAYER COULD RESULT IN HOURLY
SNOWFALL RATES OF 1 INCH TO 1 1/2 INCH THROUGH THE AFTERNOON BEFORE
FORCING BEGINS TO WANE IN THE EARLY EVENING. FORECASTED SNOWFALL
TOTALS STILL LOOKING AT JUST EITHER SIDE OF 6 INCHES ORIENTED FROM
THE CENTRAL AND EASTERN HIGHWAY 14 CORRIDOR THEN SOUTHEASTWARD THROUGH
THE CENTRAL INTERSTATE 29 CORRIDOR INTO SOUTHWESTERN
MINNESOTA...TRENDING UPWARD TO AROUND 7 INCHES IN PARTS OF
NORTHWESTERN IOWA. BLOWING SNOW SHOULD ONLY BE A RELATIVELY MINOR
ISSUE WITH WINDS STAYING IN THE 15 TO 25 KT RANGE MAINLY ACROSS
AREAS TO THE SOUTH OF INTERSTATE 90. SNOW SHOULD QUICKLY END BY
MID EVENING AS FRONTAL FORCING WEAKENS AND THE SHORTWAVE PUSHES
OFF TO THE EAST. IT WILL BE ANOTHER VERY COLD NIGHT WITH LOWS DOWN
INTO MAINLY SINGLE DIGITS BELOW ZERO. DO BEGIN TO SEE WIND CHILL
ADVISORY CRITERIA BEING MET LATER TONIGHT...BUT ELECTED TO HOLD
OFF ON THAT UNTIL CURRENT HEADLINES EXPIRE.
MIDDLE AND HIGH CLOUDS WILL AGAIN INCREASE FROM THE WEST TUESDAY AS
THE NEXT CANADIAN WAVE BEGINS TO DEEPEN THE UPPER TROUGH. MOST OF
THE INCREASE WILL BE ACROSS THE SOUTHWEST HALF OF THE AREA...AND
WILL KEEP A MENTION OF FLURRIES THERE WITH LITTLE DYNAMIC LIFT FOR
MEASURABLE SNOW.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 310 PM CST MON JAN 5 2015
SKIES WILL CLEAR TUESDAY NIGHT AS THE WAVE CONTINUES TO DIG AND THE
ARCTIC RESURGENCE POURS INTO THE FORECAST AREA WITH THE COLDEST AIR
OF THE WINTER SO FAR. WINDS BRINGING THIS SURGE WILL BE STRONG TO
CAUSE SOME BLOWING OF THE STILL FRESH SNOW COVER...WILL MENTION
TUESDAY NIGHT AND TAPER OFF WEDNESDAY AS WINDS SLOWLY DECREASE.
SKIES WEDNESDAY SHOULD BE PRETTY CLEAR. HOWEVER THE BIG NEWS WILL BE
THE WIND CHILLS DIVING TO WARNING LEVELS BY LATE TUESDAY NIGHT...
EXCEPT TO ONLY ADVISORY CRITERIA OVER THE SOUTHWEST CORNER OF THE
AREA. AFTER COORDINATION AND LOCAL INPUT...HAVE DECIDED TO HOLD OFF
ON THESE HIGHLIGHTS UNTIL THE CURRENT WARNING AND ADVISORY TONE
DOWN. HOWEVER...THOUGH IT WAS ALREADY BEEN COLD OF COURSE...THIS
IS GOING TO BE THE COLDEST SHOT OF THE WINTER SO FAR.
WEDNESDAY NIGHT WILL BRING A QUICK TURN TO WARMING...THOUGH IT WILL
GET TO THE SURFACE IN ONLY A VERY LIMITED MEASURE. A BAND OF WARM
ADVECTION CLOUDS WILL PASS OVER THE AREA WITH THIS WARMING AND EXIT
AS THE NEXT COLD AIR SHOT ARRIVES. THE TRANSITORY NATURE OF THE
WARMING LEADS TO A MENTION OF ONLY A SLIGHT CHANCE OF LIGHT SNOW IN
THE NORTHEAST CORNER OF THE AREA LATE WEDNESDAY NIGHT.
THURSDAY WILL BE NOT AS COLD...MOSTLY TEENS ABOVE ZERO...AS DELAYED
MIXING FROM THE WEDNESDAY NIGHT WARMING HELPS TEMPERATURES UP A BIT.
THE ACCOMPANYING COLD AIR REINFORCEMENT WILL MAKE FOR ANOTHER WIND
CHILL EVENT WITH A COLD DAY FRIDAY. THE COLDEST AIR WILL THEN SHIFT
EAST OF THE AREA WITH RELATIVELY MINOR WAVES AND BELOW NORMAL BUT NOT
AS FRIGID TEMPERATURES IN STORE FOR SATURDAY THROUGH MONDAY. WILL
MENTION SOME CHANCE OF LIGHT SNOW CENTRAL AND SOUTH SATURDAY AHEAD
OF THE NEXT CANADIAN HIGH...WHICH SHOULD RULE WITH DRY WEATHER AND
MODESTLY COLD TEMPERATURES AS MENTIONED ABOVE FOR SUNDAY AND MONDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1152 AM CST MON JAN 5 2015
SNOW BAND BECOMING ESTABLISHED ACROSS THE AREA WITH WIDESPREAD
VISIBILITIES OF 1/2 TO 1SM. LIFR OR WORSE WILL BE THE RULE THE
NEXT 3-6 HOURS...BUT SHOULD IMPROVE QUICKLY IN TERMS OF VISIBILITY
AND CEILING LATER IN THE AFTERNOON AND EARLY EVENING FROM WEST TO
EAST. WINDS LOOK POTENTIALLY A BIT LIGHT IN GUIDANCE FOR
LOCATIONS WEST OF THE INVERTED TROUGH DURING THE EVENING AND EARLY
OVERNIGHT MAINLY FROM THE JAMES THROUGH MISSOURI RIVER CORRIDORS.
DOUBTS AS TO IF WINDS WOULD BE STRONG ENOUGH TO PRODUCE ANY
APPRECIABLE BLOWING SNOW...BUT KSUX WOULD BE THE GREATEST RISK FOR
ANY TAF LOCATION.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR SDZ070-
071.
WINTER STORM WARNING UNTIL MIDNIGHT CST TONIGHT FOR SDZ039-040-
054>056-061-062-066-067.
WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR SDZ038-
052-053-058>060-064-065-068-069.
MN...WINTER STORM WARNING UNTIL MIDNIGHT CST TONIGHT FOR MNZ071-072-
080-081-089-090-097-098.
IA...WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR IAZ031.
WINTER STORM WARNING UNTIL MIDNIGHT CST TONIGHT FOR IAZ001>003-
012>014-020>022-032.
NE...WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR NEZ013-
014.
&&
$$
SHORT TERM...JM
LONG TERM...
AVIATION...CHAPMAN
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
1118 PM CST SUN JAN 4 2015
.UPDATE...
ISSUED AT 904 PM CST SUN JAN 4 2015
00Z MODELS ARE BEGINNING TO TRICKLE IN AND ARE IN FAIRLY GOOD
AGREEMENT WITH THE CURRENT FORECAST. HI RESOLUTION SHORT TERM
MODELS ARE STILL DIFFERING SOME ON THE TIMING. THE RAP IS A BIT
QUICKER THAN THE HRRR...BUT THE LATEST RUN OF THE HRRR IS TRENDING
CLOSER TO THE PROGRESSIVE RAP. WITH THE STRONG FORCING AND VERY
EFFICIENT ATMOSPHERE FOR PRODUCING DENDRITES...EXPECT CONDITIONS
TO RAPIDLY DETERIORATE LATE MONDAY MORNING INTO MONDAY AFTERNOON AS
BAND OF SNOW DEVELOPS ACROSS THE AREA. CONSIDERED TRENDING THE
WINTER STORM WARNING SLIGHTLY EARLIER...BUT ENOUGH UNCERTAINTY
EXISTS RIGHT NOW WITH THE PRECISE TIMING THAT IT IS BEST TO LEAVE
THINGS AS IT IS.
WITH THE DRY NATURE OF THE SNOW AND THE STRONG WINDS AT BOTH THE
ONSET AND THEN AGAIN AT THE END OF THE EVENT...TRAVEL CONDITIONS
WILL BE QUITE POOR. THOSE WITH TRAVEL PLANS MONDAY AFTERNOON INTO
MONDAY NIGHT SHOULD MAKE ALTERNATIVE PLANS.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 258 PM CST SUN JAN 4 2015
TODAY LOOKS LIKE THE CALM BEFORE THE STORM. ALL EYES CONTINUE TO
WATCH PROGRESSION OF SHORTWAVE ENERGY JUST NOW BEGINNING TO ENTER
THE WESTERN COAST OF BRITISH COLUMBIA. MEANWHILE...AN INITIAL
SHORTWAVE ACROSS MONTANA THIS MORNING CONTINUES TO DRIFT
SOUTHEAST LATE THIS AFTERNOON. IMPACTS WITH THIS WAVE LOOK TO BE
MINIMAL...WITH MUCH OF THE MID-UPR CLOUDS EXPECTED TO STAY
SOUTHEAST OF THE REGION. FOR TONIGHT...SURFACE HIGH PRESSURE WILL
DROP SOUTHEAST INTO THE AREA. LIGHT WINDS SHOULD SETUP A RATHER
COLD NIGHT TONIGHT. OVERNIGHT LOWS WILL FALL BELOW -10 IN MANY
LOCATIONS...AND WOULD NOT BE SURPRISED TO SEE A FEW SPOTS DROP
TOWARDS -15 OR LOWER. THE LIGHT WINDS WILL PRECLUDE ANY EXTREME
WIND CHILL DROP...BUT ANTICIPATING A LIGHT NORTHERLY WIND OVER THE
NORTHEASTERN THIRD OF THE CWA TO KEEP WIND CHILL ADVISORY
CONDITIONS LIKELY OVERNIGHT.
MONDAY WILL START OFF BITTERLY COLD...BUT DECEPTIVELY SUNNY. HI-RES
MODELS CONTINUE TO TREND SLIGHTLY FURTHER SOUTH WITH THE TRACK OF
THE CLIPPER HEADING INTO THE AREA...RAISING CONFIDENCE IN NUDGING
THE HIGHER SNOW TOTALS FURTHER SOUTHWEST. THROUGH THE MORNING...WE
WILL BEGIN TO SEE A RAPID INCREASE IN MID-LVL CLOUDS AS MID-LVL WARM
ADVECTION BEGINS. A STRONG LOW-LVL FRONTAL CIRCULATION IS EXPECTED
TO DEVELOP QUICKLY BY MID-DAY...WITH RAPID TOP-DOWN SATURATION
DEVELOPING INTO A FAIRLY BROAD AND ELONGATED AREA OF SNOW ACROSS THE
FORECAST AREA. AS ALLUDED TO IN PREVIOUS DISCUSSIONS...THERE IS A
HIGH LIKELIHOOD OF AN ENHANCED BAND OF SNOW WITHIN THIS BROAD
AREA...WHERE SNOWFALL RATES MAY BE EXTREMELY HIGH.
WITH SNOW DRAMATICALLY INCREASING IN THE AFTERNOON AND CONTINUING
INTO THE EARLY EVENING...TOTAL SNOWFALL COULD APPROACH 5 TO LOCALLY
8 OR MORE INCHES OF SNOW IN THE HIGHEST CORRIDOR FROM NEAR DE
SMET...THROUGH SIOUX FALLS AND FURTHER SOUTHEAST TOWARDS STORM
LAKE AND SPENCER. GIVEN DRY AIR ALONG THE NORTHEASTERN FRINGES OF
THIS SYSTEM...THE NORTHEASTERN EDGE OF SNOW MAY BE MORE SHARPLY
DEFINED THAN INDICATED IN CURRENT GRIDS.
SURFACE WINDS WILL COMPLICATE MATTERS DURING THE DAY...AS PERSISTENT
SOUTHEAST TO EAST WINDS MAY GUST AS HIGH AS 30 MPH AT TIMES. ONCE
THE SURFACE LOW PASSES EARLY IN THE EVENING...WINDS WILL TURN BACK
TO THE NORTHWEST WITH THE HIGHEST GUSTS FOCUSED ALONG THE MISSOURI
RIVER CHANNEL.
AS FAR AS HEADLINES ARE CONCERNED...CONFIDENCE HIGH ENOUGH TO
CONVERT MOST OF THE WATCH INTO A WARNING. THE CONCERN WOULD BE IN
LYON AND LINCOLN COUNTIES IN MINNESOTA WHERE THE POTENTIAL FOR A
TIGHTER NE SNOW GRADIENT MAY SPLIT THE COUNTIES. GIVEN THE
POTENTIAL FOR THIS WAVE TO DIG SLIGHTLY FURTHER...WILL LEAVE AND
EXPAND THE WATCH SLIGHTLY FURTHER SOUTHWEST TO CORRESPOND WITH THE
INCREASE IN SNOW AMOUNTS FORECAST TODAY AND POSSIBILITY OF FURTHER
WARNING EXPANSION SOUTHWARD. TRAVEL SHOULD BE ATTEMPTED WITH
EXTREME CAUTION MONDAY AFTERNOON INTO MONDAY EVENING...GIVEN THE
RAPID DETERIORATION OF CONDITIONS FROM THE FIRST HALF TO THE
SECOND HALF OF THE DAY.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 258 PM CST SUN JAN 4 2015
THE COLD AIR SURGE BEHIND THE SNOW SYSTEM MONDAY NIGHT WILL BE
OUTDONE BY A REINFORCING ARCTIC SURGE TUESDAY NIGHT AS A STRONG
CANADIAN WAVE DIGS TOWARD THE GREAT LAKES. TUESDAY WILL BE COLD
ENOUGH WITH MOSTLY SINGLE DIGIT HIGHS AND SOME CLOUDS LINGERING
BETWEEN THE EXITED STORM AND THE APPROACHING MONSTER ARCTIC HIGH.
THE SURGE WILL ARRIVE TUESDAY NIGHT WITH WINDS PICKING UP FROM THE
RELATIVELY TAME TUESDAY BREEZE. ALONG WITH THIS SURGE WILL COME SOME
BLOWING OF THE FRESH SNOW...POSSIBLY ENOUGH FOR ADVISORIES JUST FOR
THAT...AND WIND CHILLS LIKELY DIVING BELOW THE WARNING LEVEL...THAT
IS 35 TO 45 BELOW...NORTHEAST AT LEAST...BY WEDNESDAY MORNING. WINDS
SHOULD THEN DECREASE SLOWLY DURING THE DAY WEDNESDAY AS THE 1060MB
HIGH ARRIVES OVER WESTERN SOUTH DAKOTA...BUT ACTUAL HIGH
TEMPERATURES WILL BE BELOW ZERO IN MOST OF THE AREA. THE SURGE BY
THE WAY SHOULD CLEAR OUT SKIES PRETTY WELL WITH THAT HIGH GETTING
CLOSE.
A VERY FAST WARMUP SHOULD TAKE PLACE WEDNESDAY NIGHT WITH THE NEXT
WAVE AND FRONT COMING IN EARLY THURSDAY. THIS WARMUP WILL BE SO FAST
THAT IT WILL GET IN ONLY A LIMITED WAY TO THE SURFACE. IN FACT...THE
THURSDAY COLD FRONT WILL BE MORE LIKE AN OCCLUSION AS A LESS BITING
COLD AIR PLUNGE ARRIVES. AFTER HIGHS IN THE TEENS TO MID 20S
THURSDAY...FRIDAY WILL BRING HIGHS IN THE SINGLE DIGITS RANGING TO
SOME TEENS SOUTHWEST...ALL ABOVE ZERO. SATURDAY AND SUNDAY WILL BE
BACK INTO THE TEENS TO LOWER 20S FOR HIGHS...BELOW NORMAL BUT
NOT AS MUCH AS EARLY THIS WEEK.
WILL KEEP OUT MENTION OF ANY LIGHT SNOW FOR WEDNESDAY NIGHT INTO
THURSDAY...WITH THE WARMING BEING TOO FAST TO POOL ENOUGH MOISTURE.
THERE COULD THEN BE SOME ABOUT FRIDAY OR SATURDAY AS SOME SLOW WARM
ADVECTION BEGINS ALOFT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1113 PM CST SUN JAN 4 2015
THERE IS AN AREA OF UPPER END MVFR CEILINGS MOVING SOUTHEASTWARD
ACROSS THE SOUTHERN HALF OF THE SIOUX FALLS FORECAST AREA AT THIS
TIME. THIS AREA OF CLOUDS IS PRIMARILY AFFECTING THE KFSD TAF
SITE. DUE TO THE AMOUNT OF HIGH CLOUDS...IT IS DIFFICULT TO TELL
IF THESE CLOUDS WILL ACTUALLY MOVE INTO...OUR EXPAND INTO KSUX. AT
ANY RATE...DID ACCOUNT FOR SOME CEILINGS NEAR 3000 FEET AGL FOR
SIOUX FALLS FOR A SHORT PERIOD OF TIME...AND KSUX WILL BE
MONITORED. OTHERWISE THE FORECAST AREA WILL BE VFR UNTIL MONDAY
MORNING WHEN A STRONG...VIGOROUS SYSTEM MOVES SQUARELY INTO OUR
REGION. THE SURFACE LOW TRACKS FROM SOUTHEAST MT TO SOUTH CENTRAL
SD MONDAY AFTERNOON...WITH AN ATTENDANT WARM FRONT JUTTING
SOUTHEASTWARD AHEAD OF THE LOW. THEREFORE SNOWFALL WILL RAPIDLY
DEVELOP AND EXPAND ALONG AND EAST OF THE WARM FRONT AFFECTING
NEARLY ALL OF OUR FORECAST AREA. MID AND UPPER LEVEL DYNAMICS
CONTINUES TO BE VERY STRONG...WITH MID LEVEL FRONTOGENESIS IN NO
SHORT SUPPLY...WITH SOME INSTABILITY NOTED ABOVE THE FRONTOGENETIC
LAYER. THEREFORE BELIEVE THAT WIDESPREAD IFR TO LIFR CONDITIONS
WILL PREVAIL FOR AROUND A 6 TO 8 PERIOD LATE MONDAY MORNING
THROUGH EARLY MONDAY EVENING...AFFECTING THE KHON...KFSD AND KSUX
TAF SITES. CONDITIONS WILL IMPROVE MONDAY EVENING...BUT WILL HAVE
TO WATCH FOR THE THREAT OF SOME PATCHY BLOWING SNOW.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...WINTER STORM WATCH FROM MONDAY AFTERNOON THROUGH MONDAY EVENING
FOR SDZ038-053-054-061-066-070-071.
WINTER STORM WARNING FROM NOON MONDAY TO MIDNIGHT CST MONDAY
NIGHT FOR SDZ039-040-055-056-062-067.
WIND CHILL ADVISORY UNTIL NOON CST MONDAY FOR SDZ038>040-052>056-
061-062-067.
MN...WINTER STORM WARNING FROM NOON MONDAY TO MIDNIGHT CST MONDAY
NIGHT FOR MNZ071-072-080-081-089-090-097-098.
WIND CHILL ADVISORY UNTIL NOON CST MONDAY FOR MNZ071-072-080-081-
089-090-097-098.
IA...WINTER STORM WATCH FROM MONDAY AFTERNOON THROUGH MONDAY EVENING
FOR IAZ020-031-032.
WINTER STORM WARNING FROM NOON MONDAY TO MIDNIGHT CST MONDAY
NIGHT FOR IAZ001>003-012>014-021-022.
WIND CHILL ADVISORY UNTIL NOON CST MONDAY FOR IAZ001>003-012>014-
021-022-032.
NE...NONE.
&&
$$
UPDATE...
SHORT TERM...
LONG TERM...DUX
AVIATION...MJ
AREA FORECAST DISCUSSION
NWS MORRISTOWN TN
309 AM EST MON JAN 5 2015
.SHORT TERM (TODAY AND TONIGHT)...
THE MAIN FORECAST PROBLEM OF THE DAY IS HOW QUICKLY CLOUD COVER WILL
ERODE ACROSS THE AREA. THE GFS IS QUICKER THAN THE NAM AND HRRR TO
CLEAR OUT THE CLOUDS...AND WILL LEAN TOWARD THE SLOWER SOLUTION
WHICH TENDS TO OCCUR MORE OFTEN IN THIS PATTERN. STILL...WE SHOULD
HAVE MOSTLY SUNNY SKIES EVERYWHERE BY THE AFTERNOON. WITH 850 MB
COLD ADVECTION PERSISTING THROUGH THE DAY...HIGHS WILL BE IN THE 30S
TO AROUND 40 SOUTH. A SOUTHWARD DIP OF THE JET STREAM AND A SHORTAVE
TROUGH PASSING ACROSS THE GREAT LAKES/OHIO VALLEY TONIGHT MAY BRING
SOME HIGH CLOUDS TO NORTHERN AREAS AFTER MIDNIGHT.
.LONG TERM (TUESDAY THROUGH SUNDAY)...
QUIET WEATHER WILL BE THE STORY FOR MOST OF THE LONG TERM
FORECAST. ONLY A COUPLE OF ITEMS OF NOTE UPCOMING...COLD FRONT ON
WEDNESDAY AND THE NEXT SYSTEM MOVING THROUGH OVER THE WEEKEND.
COLD FRONT...COLD FRONT DOESN`T REALLY POSE MUCH IN THE WAY OF
PRECIP AS IT WILL BE RELATIVELY MOISTURE STARVED, BUT THERE IS A
CHANCE THAT IT`S STRONG ENOUGH TO SQUEEZE OUT WHAT LITTLE MOISTURE
THERE IS IN SOME PLACES. SO HAVE CONTINUED WITH MENTION OF 10
PERCENT CHANCE OF FLURRIES IN NORTHEAST TN/ SOUTHWEST VA. AFTER THE
FRONT COMES THROUGH TEMPS WILL REACH THE COLDEST WE`VE SEEN IN QUITE
SOME TIME, LOOKS LIKE THE LAST TIME MANY OF LOCATIONS WILL HAVE SEEN
TEMPS THIS COLD WAS JANUARY 30TH OF LAST YEAR.
WEEKEND SYSTEM...NOT MUCH CHANGE TO THE FORECAST IN THIS TIME FRAME,
MODELS ARE VERY SLOWLY TRYING TO COME INTO AGREEMENT WITH WHAT WILL
HAPPEN WITH THIS SYSTEM. BUT AT THIS TIME THE MODEL SPREAD IS WIDE
ENOUGH THAT IT LEADS TO RELATIVELY LOW CONFIDENCE FOR THIS SYSTEM.
LOOKS LIKE TEMPS WILL BE COLD ENOUGH OVERNIGHT ACROSS MUCH OF THE
AREA THAT IT`S WORTH MENTIONING THAT SOME LIGHT SNOW WILL BE
POSSIBLE ACROSS MUCH OF THE FORECAST AREA.
&&
.PRELIMINARY POINT TEMPS/POPS...
CHATTANOOGA AIRPORT, TN 40 26 50 27 / 0 0 10 10
KNOXVILLE MCGHEE TYSON AIRPORT, TN 38 25 48 26 / 0 0 10 10
OAK RIDGE, TN 37 24 46 26 / 0 0 10 10
TRI CITIES AIRPORT, TN 34 22 44 25 / 0 0 10 10
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
DGS/ABM
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
440 AM EST WED JAN 7 2015
.UPDATE...
THE SYNOPSIS...NEAR TERM...SHORT TERM AND LONG TERM SECTIONS HAVE
BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 438 AM EST WED JAN 7 2015
EXTREMELY COLD AIR WILL CONTINUE TO POUR INTO THE AREA TODAY THROUGH
EARLY THURSDAY AS A STRONG COLD DOME OF HIGH PRESSURE DROPS INTO THE
REGION. AREAS OF BLOWING SNOW CAN BE EXPECTED WITH WIND CHILLS WELL
BELOW ZERO AS WINDS INCREASE EVEN MORE TODAY. AN AREA OF LIGHT SNOW
SHOWERS WILL DROP SOUTH OF THE FORECAST AREA BY LATER THIS MORNING.
MEANWHILE SOME LAKE EFFECT SNOW SHOWERS ACROSS THE NORTHEAST ARE
POSSIBLE BY EARLY IN THE DAY. DRY WEATHER WILL PREVAIL FOR THE END
OF THE WEEK AND MUCH OF THE WEEKEND AS TEMPERATURES BEGIN TO
MODERATE SLIGHTLY...BUT REMAIN BELOW NORMAL THROUGH THE MAJORITY OF
THE FORECAST PERIOD. CHANCES FOR SNOW WILL APPEAR AGAIN AT THE START
OF NEXT WEEK DUE TO AN UPPER LEVEL SYSTEM MOVING THROUGH THE AREA.
&&
.NEAR TERM /EARLY THIS MORNING THROUGH THE REST OF TODAY/...
ISSUED AT 438 AM EST WED JAN 7 2015
A DISTURBANCE OVER CENTRAL ILLINOIS WHICH NONE OF THE GUIDANCE
PICKED UP ON EXCEPT THE SREF AND HRRR MOVED INTO CENTRAL INDIANA
VERY EARLY THIS MORNING AND STARTED PRODUCING SNOW AT LAF AND
CONTINUES TO DO SO AS IT DROPS SOUTH OVER THE FORECAST
AREA...CURRENTLY STILL SNOWING HERE AT IND BUT SHOULD END AROUND 6
AM. HAD TO UPDATE THE MORNING FORECAST TO ACCOUNT FOR THESE
SCATTERED SNOW SHOWERS. SREF AND HRRR IN DISAGREEMENT ABOUT WHEN THE
SNOW WILL EXIT THE AREA. THE HRRR HAS THE ACTIVITY DISSIPATING OR
SOUTH OF THE AREA BY 12Z...WHILE THE SREF DOES NOT MOVE THE SNOW OUT
OF THE AREA UNTIL 15Z. LEANED CLOSER TO THE SREF SOLUTION BASED ON
LATEST RADAR TRENDS. SO THERE WILL BE SCATTERED CHANCES FOR SNOW
SHOWERS IN THE FORECAST FROM AROUND THE I-70 CORRIDOR AND SOUTHWARD
THROUGH EARLY THIS MORNING. LITTLE TO NO SNOW ACCUMULATION IS
EXPECTED.
ELSEWHERE...LAKE EFFECT SNOW OFF THE SOUTHEASTERN SHORE OF LAKE
MICHIGAN IS SLOWLY MAKING ITS WAY SOUTH TOWARD THE NORTHEAST CORNER
OF THE FORECAST AREA. LEFT IN LOW CHANCES FOR SNOW SHOWERS FROM LATE
THIS MORNING THROUGH THE AFTERNOON HOURS BEFORE THE LAKE EFFECT
MACHINE LETS UP EARLY THIS EVENING.
NOW WE TURN TO THE BIG STORY OF THE DAY AND NEXT 24+ HOURS: THE
DANGEROUSLY COLD WIND CHILLS. EARLY THIS MORNING AFTER COMPLETING
MOST OF THE FORECAST...OPTED TO MAKE ONE ADJUSTMENT TO THE
HEADLINES. REALIZED THAT THE NORTHERN HALF OF THE AREA WHICH WAS
THEN UNDER A WIND CHILL ADVISORY WOULD BE UPGRADED TO A WARNING BY
8AM...A MERE COUPLE OF HOURS. AND SINCE THE WINDS WILL ONLY GROW
STRONGER THROUGH EARLY THIS MORNING AND TEMPERATURES WILL PLUMMET
DECIDED TO DO THE UPGRADE EARLY AND GO WITH A WARNING NOW.
CONDITIONS ARE NOT AT THIS CRITERIA YET BUT WILL BE SHORTLY THIS
MORNING. OTHERWISE LEFT THE REST OF THE HEADLINES INTACT...INCLUDING
THE ADVISORY FOR THE SOUTHERN HALF OF THE CWA...WHICH CAN BE FOUND
UNDER THE PRODUCT ID INDWSWIND. BOTH HEADLINES ARE SET TO EXPIRE AT
10 AM THURSDAY MORNING.
THOSE STRONG NORTHWEST WINDS MENTIONED ABOVE MAY ALSO CAUSE BLOWING
AND DRIFTING OF SNOW...ESPECIALLY FOR LOCATIONS ACROSS THE NORTHERN
HALF OF THE AREA WHERE MORE SNOW WAS RECEIVED YESTERDAY.
AS FOR TEMPERATURES CENTRAL INDIANA IS PROBABLY LOOKING AT THE
WARMEST TEMPS OF THE DAY RIGHT NOW. TEMPERATURE WILL PLUMMET AS
MENTIONED SO THE HIGH TEMPERATURE BETWEEN 12Z TODAY TO 00Z THU WILL
ONLY BE IN THE SINGLE DIGITS...RANGING FROM 0 (NW) TO NEAR 10 ACROSS
THE FAR SOUTH. BLEND OF GUIDANCES SEEMED TO DO A GREAT JOB.
&&
.SHORT TERM /TONIGHT THROUGH FRIDAY NIGHT/...
ISSUED AT 438 AM EST WED JAN 7 2015
TEMPERATURES REMAIN THE MAJOR FOCUS IN THE SHORT TERM WITH A
BITTERLY COLD AIR MASS IN PLACE ACROSS THE AREA. WILL CONTINUE TO
UNDERCUT MODEL NUMBERS...ESPECIALLY OVER THE SNOWPACK...OWING TO
MODEL TENDENCIES TO UNDERESTIMATE THE MAGNITUDE OF ARCTIC OUTBREAKS.
THIS RESULTS IN MIN TEMPS TONIGHT BELOW ZERO ACROSS ALL OF
CENTRAL INDIANA...WITH LOWS AROUND -10 OR BELOW ACROSS THE NORTHERN
HALF. TEMPERATURES WILL BEGIN TO MODERATE SLIGHTLY THURSDAY BUT
REMAIN QUITE COLD. SOME AREAS OF CENTRAL INDIANA...ESPECIALLY ACROSS
THE NORTH...MAY NOT SEE THE 20 DEGREE MARK UNTIL LATE IN THE WEEKEND.
APPARENT TEMPERATURES WILL CONTINUE TO WORSEN TONIGHT AS WINDS STAY
STRONG AND STEADY. CURRENT WIND CHILL WARNING ACROSS THE NORTH AND
ADVISORY ACROSS THE SOUTH HANDLES THIS WELL AND WILL REMAIN
UNCHANGED. EXPIRATION BY 10AM THURSDAY MORNING STILL LOOKS GOOD THIS
FORECAST ISSUANCE.
BY THURSDAY NIGHT A WEAK LITTLE SYSTEM OVER THE GREAT LAKES MAY
PRODUCE CHANCES FOR SCATTERED FLURRIES ACROSS THE NORTH. NO
ACCUMULATING SNOW IS EXPECTED DURING THIS TIME. TEMPERATURES BEGIN
TO SLOWLY MODERATE INTO FRIDAY HOWEVER STILL VERY COLD AND BELOW
NORMAL WITH HIGHS ONLY IN THE TEENS.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
ISSUED AT 438 AM EST WED JAN 7 2015
HIGH PRESSURE OVER THE AREA TO BEGIN THE LONG TERM. THE HIGH MOVES
OFF TO THE EAST ALLOWING WARMER AIR TO MAKE ITS WAY INTO CENTRAL
INDIANA. ANOTHER SURFACE HIGH ATTEMPTS TO BUILD IN FROM THE
NORTHWEST...BUT MODELS DIFFER ON HOW QUICKLY THIS OCCURS. GFS SHOWS
A FAIRLY QUICK TRANSITION FROM ONE HIGH TO THE NEXT BUT THE ECMWF
DEVELOPS A WEAK FRONTAL ZONE BETWEEN THE HIGHS AND BRINGS
PRECIPITATION INTO THE AREA FROM SUNDAY NIGHT ON. GIVEN THE
UNCERTAINTY KEPT THE SLIGHT TO LOW CHANCE POPS FROM THE
INITIALIZATION FROM SUNDAY NIGHT ON...BUT SHOULD NOTE THAT COULD
JUST AS EASILY SEE DRY WEATHER AS WET WEATHER FOR THE BEGINNING OF
THE WORK WEEK.
&&
.AVIATION /DISCUSSION FOR THE 070900Z TAF UPDATE/...
ISSUED AT 330 AM EST WED JAN 7 2015
LARGE AREA OF LIGHT MVFR TO IFR SNOW HAS PASSED SOUTH OF KHUF AND
KIND...BUT SET OF NW TO SE ORIENTED SNOW BANDS HAS FORMED BEHIND IT.
THIS WILL KEEP POTENTIAL FOR IFR CONDITIONS TO LAST AT KIND AND KHUF
UNTIL 11-12Z. CONDITIONS IN BETWEEN THE BANDS COULD BE VFR TO MVFR
SO WILL GO WITH PREVAILING MVFR AND TEMPO IFR DURING THIS TIME. AT
KLAF SHOULD SEE THE SNOW COME TO AN END SHORTLY IF IT HASN/T ALREADY
BUT COULD SEE SOME ISSUES WITH BLOWING SNOW SO MAY ADD THAT IN. AT
KBMG HAVEN/T SEEN THE SNOW DEVELOP BUT STILL THINK IT IS POSSIBLE
BASED ON RADAR TRENDS SO WILL KEEP CONDITIONS THERE SIMILAR TO KIND.
EXPECT GUSTS AT OR OVER 25KT BY 10-13Z. THESE GUSTS WILL CONTINUE
THROUGH 22-24Z.
CLOUDS WILL LOWER SOME OVERNIGHT BUT EXPECT BULK OF THE AREA TO
REMAIN VFR. SOME MVFR POSSIBLE IN SCATTERED SNOW SHOWERS FROM 08-12Z
OR SO MAINLY AT THE SOUTHERN SITES...BUT AT THE MOMENT FEEL ODDS ARE
LOW ENOUGH TO JUST MENTION VCSH.
LOWER CLOUDS WILL SCATTER OUT BY MID MORNING.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
WIND CHILL ADVISORY FROM 8 AM THIS MORNING TO 10 AM EST THURSDAY
FOR INZ051>057-060>065-067>072.
WIND CHILL WARNING UNTIL 10 AM EST THURSDAY FOR INZ021-028>031-
035>049.
&&
$$
SYNOPSIS...SMF
NEAR TERM...SMF
SHORT TERM...SMF
LONG TERM....CP
AVIATION...50/CP
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
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AREA FORECAST DISCUSSION
NWS GOODLAND KS
218 AM MST WED JAN 7 2015
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 134 PM MST TUE JAN 6 2015
WV IMAGERY AND RAP H5 ANALYSIS SHOW NW FLOW CONTINUING FROM THE THE
CANADIAN ROCKIES ACROSS THE PLAINS AND TO THE CENTRAL MISSISSIPPI
RIVER VALLEY. AT THE SURFACE SOUTHERLY FLOW IS IN PACE ACROSS OUR
CWA ON EASTERN EXTENT OF LEE TROUGH CENTERED OVER COLORADO.
CONTINUING TO MONITOR POSSIBLE IMPACTS OF STRONG COLD FRONT EXPECTED
TO MOVE INTO CWA TONIGHT.
REGARDING PRECIP CHANCES/TYPES...MOST PRECIPITATION WILL BE TIED
TO ELEVATED FRONTAL ZONE WHERE ISENTROPIC UPGLIDE AND FRONTOGENETIC
FORCING WILL BE IN PLACE LATER TONIGHT. BETTER MOISTURE/LIFT IS
ADVERTISED IN THE WEST WHERE MODEL QPF IS SHOWING BETTER PRECIP
SIGNAL...SO I RAISED POPS TO LIKELY CATEGORY IN COLORADO COUNTIES
09-12Z PERIOD. WHILE SATURATION DOES OCCUR BELOW 700MB...MOISTURE
ADVECTION IS WEAK AND THOUGHTS ARE ANY PRECIP AMOUNTS WILL BE VERY
LIGHT. PRECIP TYPE IS ANOTHER CONCERN. LOW LEVEL SATURATION
BEGINS IMMEDIATELY BEHIND SURFACE FRONT THIS EVENING...YET TEMP
PROFILES FAVOR SUPERCOOLED LIQUID. SATURATION AT TEMPS BELOW -8C
DOESNT OCCUR OVER OUR CWA UNTIL AFTER 09Z. I COULD SEE VERY LIGHT
FREEZING DRIZZLE DEVELOPING AHEAD OF THE MAIN AREA OF
PRECIP...TRANSITIONING TO SNOW...POSSIBLY SLEET (SUPERCOOLED
SATURATED LAYER IS AT LEAST 2500 FT DEEP). SINCE PRECIP SHOULD BE
LIGHT I AM NOT THINKING THIS WOULD AMOUNT TO MUCH IN THE WAY OF
ICE ACCUMULATIONS...BUT I CANT RULE OUT SOME SLICK SPOTS
DEVELOPING DUE TO A LIGHT GLAZE. REGARDING SNOW AMOUNTS...I CANT
SEE OUR CWA RECEIVING MUCH MORE THAN ONE INCH AND THIS WOULD
LIKELY BE LIMITED TO THE FAR WEST. SNOW MAY LINGER IN EASTERN
COLORADO INTO THE MID MORNING HOURS WEDNESDAY...BUT SHOULD
COMPLETELY TAPPER OFF BY THE AROUND MIDDAY.
WINDS WILL INCREASE IMMEDIATELY BEHIND THE FRONT THIS
EVENING...HOWEVER BEST PRESSURE RISES QUICKLY TRANSITION SOUTH.
BY TIME PRECIP IS OCCURRING I DO NOT THINK WE WOULD SEE STRONG
ENOUGH GUSTS TO CREATE A BLOWING SNOW THREAT. MAYBE MINOR DRIFTING
SNOW DUE TO WINDS IN THE 15-20 MPH RANGE (MAINLY IN EASTERN
COLORADO).
REGARDING TEMPERATURES/WIND CHILLS...VERY COLD AIR MASS MOVES BACK
OVER THE CWA AFTER 06Z...AND HOW LOW TEMPS GET WILL BE COMPLICATED
BY LIMITED RADIATIONAL COOLING DUE TO CLOUD COVER AND INCREASED
MIXING DUE TO POSSIBLE PRECIP/WIND. I STILL EXPECT MOST LOCATIONS TO
REACH THE SINGLE DIGITS FOR LOWS TONIGHT WITH THE BEST CHANCE FOR
MORNING TEMPS AROUND ZERO OR COLDER IN OUR NE CWA (MCCOOK/NORTON).
I THINK IT IS MORE LIKELY WE SEE A BIGGER DROP OFF IN WINDS
SIMILAR TO NAM SURFACE WINDS...AS SURFACE GRADIENT WEAKENS.
WHILE WIND CHILLS MAY BE AROUND -15F...BUT I AM NOT CONFIDENT
THIS WOULD BE WIDESPREAD OR PERSISTENT.
WITH ALL THIS SAID...NO ADVISORY (WINTER WEATHER OR WIND CHILL)
WILL BE ISSUED DURING THIS UPDATE...BUT WE WILL NEED TO MONITOR
FREEZING PRECIP COVERAGE AND WIND CHILLS.
.LONG TERM...(SATURDAY THROUGH TUESDAY)
ISSUED AT 218 AM MST WED JAN 7 2015
FOR THE EXTENDED FORECAST PERIOD...HAVE GONE WITH A PERSISTENCE
FORECAST THIS RUN. OVERALL...LITTLE CHANGE IN THE UPPER LEVEL
PATTERN IS EXPECTED. FORECAST GUIDANCE HAS BACKED OFF FROM
SUGGESTING A LARGE RIDGE OF HIGH PRESSURE DEVELOPS OVER THE PACIFIC
NEXT WEEK. THIS WOULD HAVE LED TO SOME WARMING FOR OUR REGION.
HOWEVER...THIS APPEARS LESS LIKELY NOW BASED ON THE LATEST GUIDANCE
SO BELOW NORMAL TEMPERATURES SHOULD CONTINUE THROUGH AT LEAST THE
MIDDLE OF NEXT WEEK.
ONE THING TO NOTE FROM THIS RUN OF THE EXTENDED PROCEDURE...THERE
MAY BE A CHANCE OF SOME PRECIPITATION...LIKELY SNOW...MONDAY NIGHT
INTO WEDNESDAY. THE LATEST EUROPEAN MODEL DEVELOPS A FAIRLY POTENT
LOW PRESSURE THAT MOVES THROUGH THE DESERT SOUTHWEST AND ACROSS OUR
REGION. SOME GEFS ENSEMBLE MEMBERS ALSO INDICATE THIS SOLUTION BUT
NOT TO THE STRENGTH OF THE CURRENT EUROPEAN MODEL RUN. IT DOES
APPEAR THAT AT LEAST A WEAK UPPER LEVEL DISTURBANCE PASSES THROUGH.
MOST LIKELY SOLUTION PRESENTLY IS THAT THERE MAY BE SOME LIGHT SNOW
BUT NOTHING TOO SIGNIFICANT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1030 PM MST TUE JAN 6 2015
MVFR CONDITIONS AT KGLD AND KMCK WILL CONTINUE FOR THE NEXT
SEVERAL HOURS WITH THE POSSIBILITY OF IFR CONDITIONS FOR A FEW
HOURS OVERNIGHT. VFR CONDITIONS WILL RETURN TO KMCK BY SUNRISE AND
BY LATE MORNING AT KGLD AS HIGH PRESSURE BUILDS INTO THE REGION.
WINDS WILL BECOME LIGHT AND VARIABLE IN THE AFTERNOON AND THEN
SHIFT TO THE SOUTH WEDNESDAY EVENING.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...RRH
AVIATION...FS
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1036 PM MST TUE JAN 6 2015
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 134 PM MST TUE JAN 6 2015
WV IMAGERY AND RAP H5 ANALYSIS SHOW NW FLOW CONTINUING FROM THE THE
CANADIAN ROCKIES ACROSS THE PLAINS AND TO THE CENTRAL MISSISSIPPI
RIVER VALLEY. AT THE SURFACE SOUTHERLY FLOW IS IN PACE ACROSS OUR
CWA ON EASTERN EXTENT OF LEE TROUGH CENTERED OVER COLORADO.
CONTINUING TO MONITOR POSSIBLE IMPACTS OF STRONG COLD FRONT EXPECTED
TO MOVE INTO CWA TONIGHT.
REGARDING PRECIP CHANCES/TYPES...MOST PRECIPITATION WILL BE TIED
TO ELEVATED FRONTAL ZONE WHERE ISENTROPIC UPGLIDE AND FRONTOGENETIC
FORCING WILL BE IN PLACE LATER TONIGHT. BETTER MOISTURE/LIFT IS
ADVERTISED IN THE WEST WHERE MODEL QPF IS SHOWING BETTER PRECIP
SIGNAL...SO I RAISED POPS TO LIKELY CATEGORY IN COLORADO COUNTIES
09-12Z PERIOD. WHILE SATURATION DOES OCCUR BELOW 700MB...MOISTURE
ADVECTION IS WEAK AND THOUGHTS ARE ANY PRECIP AMOUNTS WILL BE VERY
LIGHT. PRECIP TYPE IS ANOTHER CONCERN. LOW LEVEL SATURATION
BEGINS IMMEDIATELY BEHIND SURFACE FRONT THIS EVENING...YET TEMP
PROFILES FAVOR SUPERCOOLED LIQUID. SATURATION AT TEMPS BELOW -8C
DOESNT OCCUR OVER OUR CWA UNTIL AFTER 09Z. I COULD SEE VERY LIGHT
FREEZING DRIZZLE DEVELOPING AHEAD OF THE MAIN AREA OF
PRECIP...TRANSITIONING TO SNOW...POSSIBLY SLEET (SUPERCOOLED
SATURATED LAYER IS AT LEAST 2500 FT DEEP). SINCE PRECIP SHOULD BE
LIGHT I AM NOT THINKING THIS WOULD AMOUNT TO MUCH IN THE WAY OF
ICE ACCUMULATIONS...BUT I CANT RULE OUT SOME SLICK SPOTS
DEVELOPING DUE TO A LIGHT GLAZE. REGARDING SNOW AMOUNTS...I CANT
SEE OUR CWA RECEIVING MUCH MORE THAN ONE INCH AND THIS WOULD
LIKELY BE LIMITED TO THE FAR WEST. SNOW MAY LINGER IN EASTERN
COLORADO INTO THE MID MORNING HOURS WEDNESDAY...BUT SHOULD
COMPLETELY TAPPER OFF BY THE AROUND MIDDAY.
WINDS WILL INCREASE IMMEDIATELY BEHIND THE FRONT THIS
EVENING...HOWEVER BEST PRESSURE RISES QUICKLY TRANSITION SOUTH.
BY TIME PRECIP IS OCCURRING I DO NOT THINK WE WOULD SEE STRONG
ENOUGH GUSTS TO CREATE A BLOWING SNOW THREAT. MAYBE MINOR DRIFTING
SNOW DUE TO WINDS IN THE 15-20 MPH RANGE (MAINLY IN EASTERN
COLORADO).
REGARDING TEMPERATURES/WIND CHILLS...VERY COLD AIR MASS MOVES BACK
OVER THE CWA AFTER 06Z...AND HOW LOW TEMPS GET WILL BE COMPLICATED
BY LIMITED RADIATIONAL COOLING DUE TO CLOUD COVER AND INCREASED
MIXING DUE TO POSSIBLE PRECIP/WIND. I STILL EXPECT MOST LOCATIONS TO
REACH THE SINGLE DIGITS FOR LOWS TONIGHT WITH THE BEST CHANCE FOR
MORNING TEMPS AROUND ZERO OR COLDER IN OUR NE CWA (MCCOOK/NORTON).
I THINK IT IS MORE LIKELY WE SEE A BIGGER DROP OFF IN WINDS
SIMILAR TO NAM SURFACE WINDS...AS SURFACE GRADIENT WEAKENS.
WHILE WIND CHILLS MAY BE AROUND -15F...BUT I AM NOT CONFIDENT
THIS WOULD BE WIDESPREAD OR PERSISTENT.
WITH ALL THIS SAID...NO ADVISORY (WINTER WEATHER OR WIND CHILL)
WILL BE ISSUED DURING THIS UPDATE...BUT WE WILL NEED TO MONITOR
FREEZING PRECIP COVERAGE AND WIND CHILLS.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 136 PM MST TUE JAN 6 2015
ARCTIC AIR WILL BEGIN TO MODIFY WEDNESDAY NIGHT WITH GUSTY SOUTH
WINDS. WESTERN AND SOUTHERN PARTS OF THE FORECAST AREA WILL
BRIEFLY BENEFIT FROM A WARM FRONTAL PASSAGE THURSDAY MORNING AND
EARLY AFTERNOON...BUT ANOTHER COLD FRONT WILL MOVE THROUGH BY MID
AFTERNOON BRINGING COLDER TEMPERATURES AND A WIND SHIFT TO THE
NORTHWEST. VERY SHALLOW MOISTURE WILL GRADUALLY WORK IN BEHIND THE
FRONT FROM THE NORTHEAST THURSDAY NIGHT. ALTHOUGH UPPER FORCING
WILL BE QUITE WEAK...MOISTURE WILL BE DEEP ENOUGH TO SUPPORT LIGHT
FROZEN/FREEZING PRECIPITATION BEGINNING OVERNIGHT AND CONTINUING
INTO FRIDAY GENERALLY ALONG AND WEST OF HIGHWAY 27 INCLUDING
NORTHEAST COLORADO. THE SATURATED LAYER WILL GENERALLY BE BETWEEN
-6C AND -10C THROUGH FRIDAY MORNING AND NOT REACH -12C UNTIL
FRIDAY AFTERNOON. SO EXPECT A GENERAL TRANSITION FROM FREEZING
DRIZZLE TO SLEET TO SNOW FROM THURSDAY NIGHT THROUGH FRIDAY
AFTERNOON WITH OCCASIONAL MIXES OF ALL 3 POSSIBLE. EVEN THOUGH QPF
WILL BE VERY LIGHT THERE COULD BE SOME TRAVEL PROBLEMS WITH THE
WINTRY MIX EXPECTED.
BEYOND FRIDAY...THE UPPER FLOW ACROSS THE CONUS WILL WEAKEN
CONSIDERABLY AS THE MAIN UPPER LOW PULLS AWAY INTO EASTERN
CANADA. NORTHWEST FLOW EARLY IN THE PERIOD WILL TRANSITION TO WEAK
RIDGING OVER THE WEEKEND THEN TO A SOUTHWEST FLOW EARLY NEXT WEEK
AHEAD OF A TROUGH DIGGING INTO THE GREAT BASIN AND CENTRAL
ROCKIES. PRECIPITATION CHANCES WILL BE SLIM TO NONE IN THIS
PATTERN. TEMPERATURES WILL VERY SLOWLY MODERATE BUT REMAIN
SLIGHTLY BELOW NORMAL.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1030 PM MST TUE JAN 6 2015
MVFR CONDITIONS AT KGLD AND KMCK WILL CONTINUE FOR THE NEXT
SEVERAL HOURS WITH THE POSSIBLIITY OF IFR CONDITIONS FOR A FEW
HOURS OVERNIGHT. VFR CONDITIONS WILL RETURN TO KMCK BY SUNRISE AND
BY LATE MORNING AT KGLD AS HIGH PRESSURE BUILDS INTO THE REGION.
WINDS WILL BECOME LIGHT AND VARIABLE IN THE AFTERNOON AND THEN
SHIFT TO THE SOUTH WEDNESDAY EVENING.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...024
AVIATION...FS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
349 AM EST WED JAN 7 2015
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 427 PM EST TUE JAN 6 2015
WV IMAGERY AND RUC ANALYSIS INDICATED A RIDGE OVER THE WRN CONUS AND
A BROAD TROUGH FROM NORTHEAST CANADA INTO THE ERN CONUS RESULTING IN
WNW CYCLONIC MID/UPPER LEVEL FLOW THROUGH THE NRN GREAT LAKES. A
SHORTWAVE TROUGH MOVING THROUGH UPPER MI WAS DRAGGING A SFC TROUGH
THROUGH THE AREA. OTHERWISE...A 1051 MB ARCTIC HIGH PRES OVER W
CNTRL CANADA RIDGING INTO THE PLAINS WAS SLOWLY BUILDING TO THE EAST
BRINGING VERY COLD AIR INTO THE REGION. UPSTREAM TEMPS OVER MUCH OF
NW ONTARIO RANGED FROM -5F TO -15F LATE THIS AFTERNOON.
320-340 FLOW LES IS EXPECTED TO INCREASE TONIGHT AS WINDS VEER THIS
LATE THIS AFTERNOON AND A REINFORCING BATCH OF VERY COLD AIR MOVES
INTO THE AREA. 850 MB TEMPS ARE EXPECTED TO DROP TO AROUND
-30C...RESULTING IN VERY HIGH INSTABILITY OVER THE LAKE...LAKE
INDUCED CAPE OVER 1K J/KG. HOWEVER....THE COLD WILL DROP THE DGZ
BELOW 3K FT...KEEPING SLR VALUES CLOSER TO 20/1. THE HIGHER RES
MODELS SUGGEST THAT THE STRONGEST LOW LEVEL CONV AND HEAVIEST LES
WILL DEVELOP INTO N CNTRL UPPER MI OVER ALGER COUNTY AND N
SCHOOLCRAFT COUNTY WHERE SNOWFALL TOTALS UP TO 10 INCHES ARE
POSSIBLE TONIGHT INTO WEDNESDAY. OVER THE WEST...THE SHORTER FETCH
AND LESS FAVORABLE LOW LEVEL CONV SHOULD LIMIT SNOWFALL AMOUNTS INTO
THE 2 TO 6 INCH RANGE. AN ADVY WAS ALSO ISSUED FOR MARQUETTE COUNTY
EVEN THOUGH OVERALL AMOUNTS ONLY IN THE 1 TO 4 INCH RANGE ARE
EXPECTED. LOCATIONS NEAR BIG BAY AND EAST OF HARVEY COULD SEE SOME
OCCASIONALLY HEAVY SNOW BANDS. M-28 BETWEEN HARVEY AND MUNISING
COULD ALSO SEE SOME OCCASIONAL WHITEOUT CONDITIONS AS NW WINDS GUST
INTO THE 30-40 MPH RANGE NEAR THE SHORE.
A WIND CHILL WARNING WAS POSTED FOR THE INTERIOR WEST WITH WIND
CHILLS DROPPING TO AROUND -35. THE STRONGER WINDS AND SOME LAKE
MODIFICATION WILL LIMIT TEMP FALL OVER THE REST OF THE CWA WITH MINS
IN THE -5F TO 10F RANGE. HOWEVER...THE 10-20 MPH WINDS WILL STILL BE
STRONG ENOUGH TO LOWER WIND CHILLS TO AROUND -30...SOLIDLY INTO THE
ADVY RANGE(-25 TO -35). CONDITIONS WILL ONLY SLOWLY MODERATE WED
MORNING AS THE GUSTY WINDS CONTINUE.
AS WINDS BACK STEADILY INTO WED AFTERNOON...THE LES WILL SHIFT AND
DIMINISH OVER MOST LOCATIONS NEAR LAKE SUPERIOR. HOWEVER....A MORE
FAVORABLE FETCH INTO THE KEWEENAW MAY BRING AN INCREASE IN LES
DURING THE AFTERNOON INTO THE EVENING.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 349 AM EST WED JAN 7 2015
NAM SHOWS A 500 MB RIDGE OVER THE WEST COAST 12Z THU WITH A BROAD
AND DEEP TROUGH ACROSS THE REST OF THE COUNTRY. A REINFORCING SHOT
OF COLD AIR COMES ACROSS THE AREA THU NIGHT INTO FRIDAY WITH A
STRONG SHORTWAVE THAT MAINTAINS THE DEEP TROUGH MOVING THROUGH THE
UPPER GREAT LAKES. ALBERTA CLIPPER SYSTEM MOVES THROUGH THU
AFTERNOON INTO THU NIGHT. NAM...GFS AND ECMWF SHOW STRONG 850-500 MB
Q-VECTOR CONVERGENCE MOVING THROUGH THE AREA ON THU WHICH EXITS THE
CWA THU NIGHT. WILL SEE ABOUT AN 18 HOUR PERIOD OF LIGHT TO MODERATE
SNOW AND WILL GET ABOUT 2-5 INCHES OF SNOW OUT OF THIS THU AND THU
EVENING. HEAVIEST SNOW WILL FALL THU AFTERNOON AS BEST MOISTURE
MOVES THROUGH AND THE SYSTEM PULLS OUT THU EVENING. WENT WITH
CATEGORICAL POPS THU AFTERNOON. DID NOT MAKE TOO MANY CHANGES TO THE
GOING FORECAST OTHERWISE. WILL PROBABLY NEED TO HAVE SOME MORE WIND
CHILL ADVISORIES FOR LATE TONIGHT INTO THU MORNING...THEN AGAIN THU
NIGHT AND FRI...BUT WANT TO GET THE ONGOING EVENT OUT OF THE WAY
FIRST BEFORE ISSUING ANOTHER AND WILL LET DAYSHIFT ISSUE THE NEXT
WIND CHILL STUFF FOR LATE TONIGHT AND THU MORNING AND ELIMINATE ANY
CONFUSION THAT WOULD BE CAUSED BY MULTIPLE HEADLINES.
IN THE EXTENDED...GFS AND ECMWF SHOW A DEEP AND BROAD 500 MB TROUGH
OVER MOST OF THE U.S. 12Z SAT WITH COLD AIR OVER THE AREA. UPPER
PATTERN DOES NOT CHANGE MUCH FOR SUN OR MON AND THEN SOME
MODIFICATION OF THE AIRMASS ON TUE. MORE TROUGHING WITH A SHORTWAVE
MOVES INTO THE UPPER GREAT LAKES ON TUE. TEMPERATURES LOOK TO STAY
BELOW NORMAL FOR THIS FORECAST PERIOD WITH LAKE EFFECT SNOW
CONTINUING IN WEST TO NORTHWEST FAVORED SNOWBELTS UNTIL ABOUT
TUESDAY. DID ADD IN SOME SLIGHT CHANCE POPS FOR SAT NIGHT WITH A
POSSIBILITY OF A CLIPPER PASSING BY MAINLY TO THE SOUTH AND ECMWF
SHOWS THAT POSSIBILITY. TEMPERATURES WILL CONTINUE TO BE BELOW
NORMAL FOR THIS PERIOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1237 AM EST WED JAN 7 2015
AT CMX...LIFR TO VLIFR CONDITIONS ARE EXPECTED WITH CONTINUED NW
FLOW LES AND BLOWING SNOW. WITH VERY COLD ARCTIC AIR...FINE
SNOWFLAKES ARE VERY EFFECTIVE AT REDUCING VIS. AT KIWD...EXPECT IFR
TO LIFR CONDITIONS IN NW FLOW LES OVERNIGHT INTO WED MORNING. AT
KSAW...EXPECT IFR CONDITIONS OVERNIGHT IN NW FLOW LES AND BLSN. AS
WINDS BACK OFFSHORE W-SW WED AFTERNOON CONDITIONS SHOULD GRADUALLY
IMPROVE THROUGH LATE MORNING/AFTERNOON HRS EVENTUALLY GOING TO
VFR AT BOTH KIWD AND KSAW.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 427 PM EST TUE JAN 6 2015
MUCH OF THIS PERIOD WILL BE MARKED BY HEAVY FREEZING SPRAY...WITH
INTERMITTENT GALES. CURRENTLY HAVE HEAVY FREEZING SPRAY WARNINGS
POSTED ALL THE WAY THROUGH SATURDAY MORNING. ACTIVE WEATHER FORECAST
WITH GALE EVENTS AND HEAVY FREEZING SPRAY CAN BE EXPECTED THROUGH
SATURDAY.
THE NW GALES DEVELOPING TONIGHT WILL GRADUALLY BACK TO WRLY LATE WED
AND THEN DIMINISH ON THU. ANOTHER COLD FRONT MOVING THROUGH THU
NIGHT INTO FRI WILL BRING THE NEXT PERIOD OF NW GALES WHICH ARE
EXPECTED TO GRADUALLY DIMINISH LATE FRI NIGHT INTO SAT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY UNTIL 11 AM EST THIS MORNING FOR
MIZ004-084.
WIND CHILL ADVISORY UNTIL 1 PM EST /NOON CST/ THIS AFTERNOON FOR
MIZ001>007-012-013-084-085.
LAKE EFFECT SNOW WARNING UNTIL 1 PM EST THIS AFTERNOON FOR
MIZ006-085.
WINTER WEATHER ADVISORY UNTIL 7 AM EST THURSDAY FOR MIZ001-003.
LAKESHORE FLOOD ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
MIZ001>003.
LAKE EFFECT SNOW ADVISORY UNTIL 1 PM EST /NOON CST/ THIS
AFTERNOON FOR MIZ002-009-013-014.
WIND CHILL WARNING UNTIL NOON CST TODAY FOR MIZ009>011.
LAKESHORE FLOOD ADVISORY UNTIL 7 AM EST THURSDAY FOR MIZ006-007.
LAKE EFFECT SNOW ADVISORY UNTIL 4 AM EST THURSDAY FOR MIZ007.
LAKE EFFECT SNOW ADVISORY UNTIL 10 AM EST THIS MORNING FOR
MIZ005.
LAKESHORE FLOOD ADVISORY UNTIL 7 PM EST THIS EVENING FOR MIZ005.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING UNTIL 1 PM EST /NOON CST/ SATURDAY
FOR LSZ240>251-263>267.
GALE WARNING UNTIL 1 PM EST THURSDAY FOR LSZ249>251-266-267.
GALE WARNING UNTIL 7 AM EST /6 AM CST/ THURSDAY FOR LSZ241>245-
248-263>265.
GALE WARNING UNTIL 11 AM EST /10 AM CST/ THIS MORNING FOR LSZ162-
240.
HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST /6 AM CST/ SATURDAY
FOR LSZ162.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...07
AVIATION...VOSS
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1239 AM EST WED JAN 7 2015
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 427 PM EST TUE JAN 6 2015
WV IMAGERY AND RUC ANALYSIS INDICATED A RIDGE OVER THE WRN CONUS AND
A BROAD TROUGH FROM NORTHEAST CANADA INTO THE ERN CONUS RESULTING IN
WNW CYCLONIC MID/UPPER LEVEL FLOW THROUGH THE NRN GREAT LAKES. A
SHORTWAVE TROUGH MOVING THROUGH UPPER MI WAS DRAGGING A SFC TROUGH
THROUGH THE AREA. OTHERWISE...A 1051 MB ARCTIC HIGH PRES OVER W
CNTRL CANADA RIDGING INTO THE PLAINS WAS SLOWLY BUILDING TO THE EAST
BRINGING VERY COLD AIR INTO THE REGION. UPSTREAM TEMPS OVER MUCH OF
NW ONTARIO RANGED FROM -5F TO -15F LATE THIS AFTERNOON.
320-340 FLOW LES IS EXPECTED TO INCREASE TONIGHT AS WINDS VEER THIS
LATE THIS AFTERNOON AND A REINFORCING BATCH OF VERY COLD AIR MOVES
INTO THE AREA. 850 MB TEMPS ARE EXPECTED TO DROP TO AROUND
-30C...RESULTING IN VERY HIGH INSTABILITY OVER THE LAKE...LAKE
INDUCED CAPE OVER 1K J/KG. HOWEVER....THE COLD WILL DROP THE DGZ
BELOW 3K FT...KEEPING SLR VALUES CLOSER TO 20/1. THE HIGHER RES
MODELS SUGGEST THAT THE STRONGEST LOW LEVEL CONV AND HEAVIEST LES
WILL DEVELOP INTO N CNTRL UPPER MI OVER ALGER COUNTY AND N
SCHOOLCRAFT COUNTY WHERE SNOWFALL TOTALS UP TO 10 INCHES ARE
POSSIBLE TONIGHT INTO WEDNESDAY. OVER THE WEST...THE SHORTER FETCH
AND LESS FAVORABLE LOW LEVEL CONV SHOULD LIMIT SNOWFALL AMOUNTS INTO
THE 2 TO 6 INCH RANGE. AN ADVY WAS ALSO ISSUED FOR MARQUETTE COUNTY
EVEN THOUGH OVERALL AMOUNTS ONLY IN THE 1 TO 4 INCH RANGE ARE
EXPECTED. LOCATIONS NEAR BIG BAY AND EAST OF HARVEY COULD SEE SOME
OCCASIONALLY HEAVY SNOW BANDS. M-28 BETWEEN HARVEY AND MUNISING
COULD ALSO SEE SOME OCCASIONAL WHITEOUT CONDITIONS AS NW WINDS GUST
INTO THE 30-40 MPH RANGE NEAR THE SHORE.
A WIND CHILL WARNING WAS POSTED FOR THE INTERIOR WEST WITH WIND
CHILLS DROPPING TO AROUND -35. THE STRONGER WINDS AND SOME LAKE
MODIFICATION WILL LIMIT TEMP FALL OVER THE REST OF THE CWA WITH MINS
IN THE -5F TO 10F RANGE. HOWEVER...THE 10-20 MPH WINDS WILL STILL BE
STRONG ENOUGH TO LOWER WIND CHILLS TO AROUND -30...SOLIDLY INTO THE
ADVY RANGE(-25 TO -35). CONDITIONS WILL ONLY SLOWLY MODERATE WED
MORNING AS THE GUSTY WINDS CONTINUE.
AS WINDS BACK STEADILY INTO WED AFTERNOON...THE LES WILL SHIFT AND
DIMINISH OVER MOST LOCATIONS NEAR LAKE SUPERIOR. HOWEVER....A MORE
FAVORABLE FETCH INTO THE KEWEENAW MAY BRING AN INCREASE IN LES
DURING THE AFTERNOON INTO THE EVENING.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 318 PM EST TUE JAN 6 2015
THE UPPER TROUGH THAT IS CURRENTLY COVERING EASTERN CANADA AND THE
GREAT LAKES REGION WILL REMAIN IN PLACE FOR MUCH OF THE LONG TERM
PERIOD BEFORE FINALLY LIFTING OUT OF THE AREA EARLY NEXT WEEK. WITH
THE TROUGH IN PLACE...WAVES OF COLD AIR WILL CONTINUE TO SWEEP
ACROSS THE REGION AND LEAD TO BELOW NORMAL TEMPERATURES AND LAKE
EFFECT SNOW.
LAKE EFFECT SNOW WILL BE ONGOING IN THE WEST-NORTHWEST WIND SNOW
BELTS ON WEDNESDAY NIGHT...AS THE AREA IS BETWEEN A LOW OVER HUDSON
BAY AND A HIGH IN THE MID MISSISSIPPI VALLEY. WITH THE HIGH
SHIFTING TO THE EAST THROUGH THE NIGHT...WOULD EXPECT THE LAKE
EFFECT TO TRANSITION TO THE WESTERLY WIND FAVORED
LOCATIONS...LARGELY OVER THE KEWEENAW AND RIGHT ALONG THE LAKE
SUPERIOR SHORELINE EAST OF MUNISING. INVERSION HEIGHTS DURING THIS
PERIOD LOOK TO BE AROUND 6-7KFT AND IT APPEARS DRIER AIR MOVING
INTO THE AREA WILL LIMIT THE INTENSITY OF THE OF THE LES WEDNESDAY
NIGHT AND CONTINUING INTO THURSDAY MORNING AS WINDS SHIFT MORE TO
THE SOUTHWEST AHEAD OF AN APPROACHING CLIPPER.
A SHORTWAVE DIVING SOUTHEAST OUT OF CANADA WILL STRENGTHEN A TROUGH
OVER NORTHERN ONTARIO AND MINNESOTA THURSDAY MORNING AND THEN DRAG
IT SOUTHEAST ACROSS THE UPPER GREAT LAKES REGION THURSDAY
AFTERNOON. A PERIOD OF STRONG BUT BRIEF MID LEVEL WARM AIR
ADVECTION WILL SWEEP ACROSS THE SOUTHERN HALF OF THE CWA DURING THE
LATE MORNING AND AFTERNOON HOURS. WILL CONTINUE TO SHOW A PERIOD OF
LIKELY POPS AS THAT CLIPPER MOVES THROUGH THE AREA. STILL THINK
SNOWFALL AMOUNTS WILL BE IN THE 0.5-2.0 INCH RANGE...BUT WILL NEED
TO KEEP AN EYE ON SNOW RATIOS AS SOME OF THE MODELS INDICATE A VERY
DEEP CLOUD WITHIN THE DGZ WHICH COULD PRODUCE RATIOS OF 25-30 TO
ONE.
BEHIND THE CLIPPER...ANOTHER ROUND OF LAKE EFFECT WILL DEVELOP AS
850MB TEMPS FALL FROM -16C AT 18Z THURSDAY TO -26C BY 12Z FRIDAY
UNDER NORTHWESTERLY WINDS. WITH THE DEEPER MOISTURE PRESENT AND
FAIRLY HIGH INVERSION HEIGHTS...EXPECT A PERIOD OF MODERATE SNOW
DURING THE EVENING HOURS BEFORE GRADUALLY DIMINISHING OVERNIGHT AS
INVERSION HEIGHTS LOWER. AS HAS BEEN THE CASE WITH THE LAST COUPLE
OF EVENTS...EXPECT THE COLD AIR TO LEAD TO SNOW RATIOS AND FINER
FLAKES...THUS LEADING TO SNOW THAT IS EFFICIENT AT REDUCING
VISIBILITIES. AS A STARTING POINT...HAVE PUT 12HR AMOUNTS OF 2-4IN
FOR THE NORTHWEST WINDS BELTS THURSDAY NIGHT AND IN THE
WEST-NORTHWEST WIND AREAS ON FRIDAY. THE GUSTY WINDS BEHIND THE
CLIPPER SYSTEM WILL LEAD TO ANOTHER NIGHT OF LOW WIND CHILLS...WITH
MUCH OF THE WESTERN HALF OF UPPER MICHIGAN IN THE -20 TO -30 DEGREE
RANGE.
THE POCKET OF VERY COLD AIR WILL SHIFT EAST OF THE AREA ON
FRIDAY...LEADING TO A VERY SLOW MODERATION TO TEMPERATURES ALOFT
UNDER WEST-NORTHWEST WINDS. THEREFORE...WOULD EXPECT LAKE EFFECT TO
TRANSITION TO THE WESTERLY WIND AREAS ON FRIDAY AND REMAIN THROUGH
MUCH OF THE WEEKEND...AS ANOTHER HIGH DROPS FROM THE NORTHERN
PLAINS...THROUGH THE MID MISSISSIPPI VALLEY AND INTO THE MID
ATLANTIC STATES. THE LAKE EFFECT WILL START TO DIMINISH SUNDAY
NIGHT AND MONDAY BEHIND THE FINAL SHORTWAVE SWEEPING ACROSS THE
AREA SUNDAY NIGHT AND WITH THE UPPER TROUGH SHIFTING
EAST-NORTHEAST. THAT WILL ALLOW A HIGH TO MOVE DIRECTLY ACROSS THE
UPPER GREAT LAKES REGION ON MONDAY. THE HIGH WILL SHIFT TO THE NEW
ENGLAND STATES ON TUESDAY...BUT KEEP A LINGERING RIDGE OVER THE
AREA. THE DRY AIR AND SUBSIDENCE WITH THE RIDGE...COMBINED WITH
MODERATING 850MB TEMPS TO AROUND -10C...WILL LEAD TO DIMINISHING
LES CHANCES AND TEMPERATURES STARTING TO TREND BACK TOWARDS NORMAL.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1237 AM EST WED JAN 7 2015
AT CMX...LIFR TO VLIFR CONDITIONS ARE EXPECTED WITH CONTINUED NW
FLOW LES AND BLOWING SNOW. WITH VERY COLD ARCTIC AIR...FINE
SNOWFLAKES ARE VERY EFFECTIVE AT REDUCING VIS. AT KIWD...EXPECT IFR
TO LIFR CONDITIONS IN NW FLOW LES OVERNIGHT INTO WED MORNING. AT
KSAW...EXPECT IFR CONDITIONS OVERNIGHT IN NW FLOW LES AND BLSN. AS
WINDS BACK OFFSHORE W-SW WED AFTERNOON CONDITIONS SHOULD GRADUALLY
IMPROVE THROUGH LATE MORNING/AFTERNOON HRS EVENTUALLY GOING TO
VFR AT BOTH KIWD AND KSAW.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 427 PM EST TUE JAN 6 2015
MUCH OF THIS PERIOD WILL BE MARKED BY HEAVY FREEZING SPRAY...WITH
INTERMITTENT GALES. CURRENTLY HAVE HEAVY FREEZING SPRAY WARNINGS
POSTED ALL THE WAY THROUGH SATURDAY MORNING. ACTIVE WEATHER FORECAST
WITH GALE EVENTS AND HEAVY FREEZING SPRAY CAN BE EXPECTED THROUGH
SATURDAY.
THE NW GALES DEVELOPING TONIGHT WILL GRADUALLY BACK TO WRLY LATE WED
AND THEN DIMINISH ON THU. ANOTHER COLD FRONT MOVING THROUGH THU
NIGHT INTO FRI WILL BRING THE NEXT PERIOD OF NW GALES WHICH ARE
EXPECTED TO GRADUALLY DIMINISH LATE FRI NIGHT INTO SAT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY UNTIL 11 AM EST THIS MORNING FOR
MIZ004-084.
WIND CHILL ADVISORY UNTIL 1 PM EST /NOON CST/ THIS AFTERNOON FOR
MIZ001>007-012-013-084-085.
LAKE EFFECT SNOW WARNING UNTIL 1 PM EST THIS AFTERNOON FOR
MIZ006-085.
WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR MIZ001-
003.
LAKESHORE FLOOD ADVISORY UNTIL 7 AM EST THIS MORNING FOR
MIZ001>003.
LAKE EFFECT SNOW ADVISORY UNTIL 1 PM EST /NOON CST/ THIS
AFTERNOON FOR MIZ002-007-009-013-014.
WIND CHILL WARNING UNTIL NOON CST WEDNESDAY FOR MIZ009>011.
LAKESHORE FLOOD ADVISORY UNTIL 7 AM EST THURSDAY FOR MIZ005>007.
LAKE EFFECT SNOW ADVISORY UNTIL 10 AM EST THIS MORNING FOR
MIZ005.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING UNTIL 1 PM EST /NOON CST/ SATURDAY
FOR LSZ240>251-263>267.
GALE WARNING UNTIL 7 AM EST THURSDAY FOR LSZ243>245-248>251-
264>267.
GALE WARNING UNTIL 7 AM EST /6 AM CST/ THIS MORNING FOR LSZ162-
240>242-263.
HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST /6 AM CST/ SATURDAY
FOR LSZ162.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...SRF
AVIATION...VOSS
MARINE...JLB
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1149 PM EST TUE JAN 6 2015
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 312 PM EST TUE JAN 6 2015
WINDY AND COLD WEATHER IS EXPECTED THROUGH FRIDAY. EXPECT
SIGNIFICANT SNOW ACCUMULATIONS NEAR LAKE MICHIGAN TONIGHT INTO
WEDNESDAY.
A STORM SYSTEM MOVING THROUGH THE GREAT LAKES WILL BRING
SNOW TO THE ENTIRE AREA THURSDAY NIGHT INTO FRIDAY...BUT ONCE AGAIN
THE HEAVIEST SNOW WILL BE NEAR THE LAKESHORE.
THE COLD WEATHER WILL CONTINUE THROUGH SATURDAY WITH ADDITIONAL SNOW
ACCUMULATIONS NEAR LAKE MICHIGAN. A SLOW WARM UP BEGINS SUNDAY AND
CONTINUES INTO NEXT WEEK.
&&
.UPDATE...
ISSUED AT 905 PM EST TUE JAN 6 2015
NO HEADLINE OR SIGNIFICANT FCST CHANGES ARE NECESSARY THIS
EVENING. WNW TO NW FLOW LES BANDS WILL GRADUALLY BECOME HEAVIER
AND MORE FOCUSED ACROSS OUR LAKESHORE COUNTIES VERY LATE THIS
EVENING AND OVERNIGHT AS H8 TEMPS CONTINUE TO FALL TO AROUND -24 C
BY 12Z WED. THE COMBINATION OF OCCASIONALLY HEAVY LAKE EFFECT SNOW
SHOWERS AND COLD TEMPS AND WINDY CONDITIONS WILL RESULT IN
HAZARDOUS TRAVEL CONDITIONS ACROSS THE ADVISORY AREA LATE TONIGHT
THROUGH MUCH OF WEDNESDAY.
&&
.SHORT TERM...(TONIGHT THROUGH THURSDAY NIGHT)
ISSUED AT 312 PM EST TUE JAN 6 2015
STORM TERM...(TONIGHT THROUGH WEDNESDAY)
I CONTINUED THE WINTER WEATHER ADVISORY I ISSUED AROUND NOON FOR
THE LAKE SHORE COUNTIES FROM AROUND 10 PM TONIGHT UNTIL WEDNESDAY
AFTERNOON. THE HIGH RESOLUTION MODELS (ARW...NMM...NAM AND AS FAR
OUT AS IT NOW GOES THE HRRR) ALL SHOW A DOMINANT SNOW BAND SETTING
UP FROM AROUND MUSKEGON THROUGH GRAND HAVEN THROUGH THE CITY OF
ALLEGAN AND THROUGH OSHTEMO BY 01 AM. THAT BAND ONLY VERY SLOWLY
ROTATES CLOSER TO THE LAKE SHORE BY 7 AM. FROM THERE IT REMAINS A
GOOD PART OF THE DAY ONLY TO ROTATES BACK INLAND SLIGHTLY LATE IN
THE DAY BUT BY THEN IT IS WEAKENING.
THE NAM...ARW...NMM...RAP AND HRRR ALL SHOW STRONG LIFT NEAR AND
JUST ABOVE THE DGZ... MOISTURE DEPTH TO 8000 FT...AND WINDS
NORTHWEST (310-320 DEGREES) WITH ONLY MINOR SHIFTING IN DIRECTION
BETWEEN 1 AM AND 2 PM WEDNESDAY IN THAT DOMINANT SNOW BAND LOCATION.
SOME LIMITING FACTORS WOULD BE THE BEST LIFT IS ABOVE THE DGZ...THE
DGZ IS NEARLY ON THE GROUND. EVEN SO THE LIFT IS IMPRESSIVE AND
PERSISTENT FOR OVER 12 HOURS IN NEARLY THE SAME LOCATIONS. SO...I
HAVE TO IMAGINE 6 TO 10 INCHES OF SNOW IS MORE THAN LIKELY IN THAT
AREA. I DO NOT SEE BLOWING SNOW AS A MAJOR ISSUE WITH THIS EVENT
SINCE WIND GUSTS OVER 30 MPH WILL BE LIMITED TO THE IMMEDIATE LAKE
SHORE (YOU HAVE TO BE ON THE BEACH TO GET WIND GUSTS HIGHER THAN 30
MPH). STILL THERE WILL BE SOME BLOWING AND DRIFTING SNOW AS WINDS
WILL BE GUSTING AT TIMES TO NEAR 25 MPH INLAND OF LAKE MICHIGAN. THE
ADVISORY SHOULD INCLUDE ALL OF THE LAKE SHORE COUNTIES FROM
MASON THROUGH VAN BUREN. I WILL HAVE LAKE COUNTY IN THE ADVISORY
TOO BUT IT WILL REALLY ONLY BE ITS EXTREME WESTERN SECTION THAT
WILL BE IMPACTED.
REST OF SHORT TERM...(WEDNESDAY NIGHT THROUGH THURSDAY NIGHT)
FORECAST CONCERNS AFTER WEDNESDAY DEAL WITH APPARENT TEMPERATURES
WEDNESDAY NIGHT AND THURSDAY AND THE ARRIVAL OF ANOTHER ARCTIC
FRONT THURSDAY NIGHT.
CERTAINLY THE COLD WEATHER WILL CONTINUE. A LARGE...1052MB...HIGH IS
PROGD TO SETTLE OVER THE PLAINS LATE WEDNESDAY. ALTHOUGH BOUNDARY
LAYER TEMPS WILL WARM...TEMPS OVER THE LAKE WILL STILL BE COLD
ENOUGH TO GENERATE ENOUGH INSTABILITY TO SUPPORT LAKE EFFECT SNOW.
GENERALLY AN INCH OR LESS IS EXPECTED. BREEZY CONDITIONS ARE STILL
EXPECTED AND IT/S POSSIBLE WE/LL NEED A WIND CHILL ADVISORY
WEDNESDAY NIGHT AND THURSDAY MORNING FOR ALL BUT THE LAKE SHORE
COUNTIES AS APPARENT TEMPERATURES LOOK LIKE THEY/LL BE AROUND -15 OR
SO. WE/LL TAKE ANOTHER LOOK AT THIS TONIGHT.
ANOTHER ARCTIC FRONT WILL MOVE THROUGH THURSDAY EVENING. H8 TEMPS
FALL TO AROUND -22C. THIS SYSTEM WILL BRING SOME SYNOPTIC SNOW AND
LAKE EFFECT SNOW AND MAY ACCUMULATE 3-6 INCHES...HIGHEST OVER THE
WESTERN CWA. WE MAY NEED AN ADVISORY FOR THAT TOO.
.LONG TERM...(FRIDAY THROUGH TUESDAY)
ISSUED AT 312 PM EST TUE JAN 6 2015
DUE TO A DEPARTING SHORTWAVE AND LAKE ENHANCEMENT... SNOW WILL BE
FALLING AS THE LONG TERM BEGINS. LAKE EFFECT SNOW SHOULD CONTINUE
THROUGH AT LEAST SATURDAY... WHEN CONDITIONS START TO BECOME
UNFAVORABLE. SATURDAY AFTERNOON... COULD SEE TEMPERATURES AT 850 MB
WARMING AND THE FLOW ALOFT BECOMING LESS CYCLONIC. A WEAK SHORTWAVE
MAY POSSIBLY PASS ACROSS THE AREA SUNDAY... BRIEFLY INCREASING THE
CHANCE FOR SNOW. HAVE SOME SNOW CONTINUING INTO SUNDAY NIGHT AND
THEN WENT WITH A DRY FORECAST THROUGH TUESDAY... AS THE NEXT SYSTEM
LOOKS TO BE SOUTH OF THE STATE.
TEMPERATURES WILL REMAIN COLD THROUGH THE LONG TERM. A MODERATING
TREND IS EXPECTED TO BEGIN SUNDAY NIGHT. HIGHS IN THE TEENS
FRIDAY... SATURDAY AND SUNDAY. WILL WARM INTO THE LOWER TO MID 20S
FOR MONDAY AND TUESDAY. THIS IS STILL A LITTLE BELOW NORMAL FOR THIS
TIME OF YEAR.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1149 PM EST TUE JAN 6 2015
HIGHLY VARIABLE CONDITIONS EXIST LATE THIS EVENING AS LAKE EFFECT
SNOW BANDS IMPACT MUCH OF THE AREA. CONDITIONS HAVE BEEN BOUNCING
BETWEEN IFR IN THE SNOW SHOWERS AND MVFR/VFR OUTSIDE OF THEM.
BY 09Z WE EXPECT THAT THE TERMINALS EAST OF A LINE FROM MKG TO AZO
WILL BECOME PREDOMINATELY VFR AS LAKE EFFECT SNOW SHOWERS END DUE
TO THE WINDS BECOMING NORTH NORTHWEST. MKG AND AZO MEANWHILE WILL
CONTINUE TO IMPACTED BY THE SNOW BANDS SO THESE TWO SITES SHOULD
BE IFR MUCH OF THE NIGHT INTO WEDNESDAY. CONFIDENCE IN THIS IS
HIGHER AT MKG SINCE AZO WILL PROBABLY BE ON THE EASTERN EDGE OF
THE SNOW BANDS.
NORTHWEST SFC WINDS OF 15 TO 25 KTS ARE EXPECTED TONIGHT AND
WEDNESDAY... DIMINISHING SOMEWHAT WEDNESDAY NIGHT WHILE BACKING TO
THE WEST. THE SNOW BANDS NEAR THE LAKESHORE SHOULD MOVE BACK
INLAND AGAIN AFTER 00Z THUR DUE TO THE BACKING LOW LEVEL FLOW.
&&
.MARINE...
ISSUED AT 312 PM EST TUE JAN 6 2015
TO SIMPLIFY THINGS...WE ENDED THE SCA A LITTLE EARLY AND BUMPED UP
THE GALE AND HEAVY FREEZING SPRAY WARNING TO BEGIN LATE THIS
AFTERNOON. WINDS WILL INCREASE AS THE ARCTIC FRONT MOVES THROUGH
TONIGHT AND WILL GUST TO 40 KNOTS. GIVEN TEMPERATURES IN THE TEENS
OVER THE LAKE...HEAVY FREEZING SPRAY IS EXPECTED AND MARINERS CAN
EXPECT SIGNIFICANT ICE ACCRETION. WINDS WILL DIMINISH WEDNESDAY
AFTERNOON BUT FREEZING SPRAY CAN BE EXPECTED THROUGH THURSDAY NIGHT.
&&
.HYDROLOGY...
ISSUED AT 1203 PM EST TUE JAN 6 2015
THE POTENTIAL FOR FREEZE UP ICE JAMS ON AREA RIVERS WILL CONTINUE
INTO THE WEEKEND. RIVERS ARE BECOMING ICE COVERED. AVERAGE AIR
TEMPERATURES WILL CONTINUE WELL BELOW 20 DEGREES... WITH HIGHS
ONLY IN THE TEENS THROUGH THE WEEK. THIS WILL AID IN ICE
FORMATION.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...WINTER WEATHER ADVISORY UNTIL 4 PM EST WEDNESDAY FOR MIZ037-038-
043-050-056-064-071.
LM...HEAVY FREEZING SPRAY WARNING UNTIL 7 PM EST WEDNESDAY FOR
LMZ844>849.
GALE WARNING UNTIL 4 PM EST WEDNESDAY FOR LMZ844>849.
&&
$$
UPDATE...LAURENS
SYNOPSIS...WDM
SHORT TERM...93
LONG TERM...63
AVIATION...MEADE
HYDROLOGY...63
MARINE...93
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1150 PM CST Tue Jan 6 2015
.UPDATE:
Issued at 1002 PM CST Tue Jan 6 2015
Band of snow over west central has been taking shape the past
couple of hours as band of mid level frontogenesis has been
strengthening per recent runs of the RAP. Reports under the band
have been generally light to moderate in intensity with little in
the way of accumulations. RAP shows that the frontogenesis will
move quickly across central and east central Missouri into
southwest Illinois through 10Z. Have gone with likely PoPs in the
path of this band with potential of up to 1/2 inch of snowfall
given the speed of this system. Otherwise the rest of the forecast
still looks on track with wind chills falling into advisory range
by early morning over northeast MO/west central IL.
Britt
&&
.SHORT TERM: (Tonight-Wednesday)
Issued at 345 PM CST Tue Jan 6 2015
Cold air in the wake of last night`s clipper currently building into
area, but the true motherload of Arctic air is still up in the
northern Plains and upper Mississippi Valley and charging our way.
It`s difficult to determine exactly where the leading edge of this
even colder AMS is, but going by NW winds gusting into the 20-30kt
range seems to suggest it has reached e SD and sw MN attm.
Latest hi-res and synoptic guidance generally supports going temp
and wind trends for tonight and into Wednesday, and by any measure
the next 24 hours are going to be extremely cold. Temperatures will
begin to drop over the next few hours but should really begin to
tumble after midnight when the next round of Arctic air hits, and by
mid morning Wednesday expect ambient air temps of -3 to -5 over our
N counties, with readings near 10 above hanging on in far s sections
of the FA. These temps, combined with the sustained NW winds of
15-20 mph will lead to bitterly cold wind chills...easily in the -15
to -25 range over the northern half of the CWA. Current wind chill
headlines still look to be on the mark, but I have expanded the
advisory to include another row of counties from Crawford Co MO to
Randolph Co IL to blend with headlines planned by SGF and PAH.
Due to the bare ground we should see a bit of a temperature bounce
during the afternoon, but it will be very minimal.
Models are still forecasting a quick shot of snow across the CWA
overnight, in entrance region of 160kt jet core over the lower Great
Lakes. 850-700mb frontogenetic forcing suggests a slightly more
northern track of this narrow snow band, and light snow is now
showing up on regional 88D imagery just west of FSD. So, have made
a slight nwd adjustment to the slight chance/low chance PoPs. Its
certainly possibly that there will be an extremely narrow corridor
where the PoPs should be much higher and that could receive some
accumulating snow, but this adjustment will have to wait until radar
echoes begin to show the orientation and location of this narrow
band.
An aside...we recently received a call from St. Francois County that
underground pops and booms are occurring. Believe these may be ice
or frost quakes...cryoseisms. If that is indeed the case, these
reports should certainly increase due to the aforementioned
temperature trends.
Truett
.LONG TERM: (Wednesday Night-Tuesday)
Issued at 336 PM CST Tue Jan 6 2015
(Wednesday Night through Friday)
Temperatures remain the primary forecast concern for the rest of
the work week as the midweek intrusion of Arctic air moves to the
east, followed by another...but less intense...round of Arctic air
on Friday.
Wednesday night`s lows will be interesting as the center of the
Arctic high tracks from eastern KS to the Ohio Valley. The night
will certainly begin very cold over our n counties, but the return
flow developing on the north side of the surface high combined
with some increase of mid and high clouds should inhibit a big
nocturnal temp drop, and actually expect a bit of a rebound in
temps in the 06-12z time frame due to the increase in mixing and
clouds that is progged over this area. However, With the ridge
axis hanging over over the eastern Ozarks during the predawn hours
temperatures in the south should fall most of the night, and it
may be that some locations here will be as cold as those in the
north. As mentioned yesterday it is difficult to get mins below
zero without snow cover, but it certainly looks like most areas
will be able to achieve this on Wednesday night due to the strength
of the cold air.
The southeast push of the ridge across the area will also produce
some odd wind chill trends. Some areas in the advisory will likely
warm above criteria for a time on Wednesday evening, before the
increasing winds in the return flow drop them back into the
criteria by daybreak. It may well be that we will have to make
some adjustments in the headlines once we can better pin down
these trends.
No major changes to going forecasts for Thursday-Friday. The
return flow should produce a bit of a moderation on Thursday, with
temps dropping once again on Friday as the next batch of Arctic
air pours into the mid-Mississippi Valley. I did trend just a bit
colder on Friday night, as center of the next surface ridge
should be parked over the area for much of the night.
(Saturday-Tuesday)
Medium range guidance still indicates a very gradual moderation in
temps heading into the start of the new week as the flow pattern
transitions to a zonal flow look over the central CONUS. I`ve also
continued some chance snow PoPs in the Sunday-Tuesday time
frame...although the signals are certainly not strong, model consensus
does indicate some warm advection as well as dynamics will be
impacting the region during this time frame.
Truett
&&
.AVIATION: (For the 06z TAFs through 06z Wednesday Night)
Issued at 1134 PM CST Tue Jan 6 2015
Snow has overspread the the area along and north of the I-70
corridor. While most of the area is still reporting VFR
conditions, there are areas reporting IFR vsbys with readings
between 1-2SM. Radar presentation indicates these are transient
bands of heavier snow, and that these lowered vsbys won`t last
very long at any given location. Snow should end from north to
south through the pre-dawn hours, with some lingering flurries
south of the I-70/I-64 corridors through early morning. Still
thinking there will be lingering ceilings between 2000-3000FT
at least through late morning, but very dry air associated with
the arctic airmass moving into the area should help to break up
the ceilings later in the day. Northwest winds sustained at 15 to
20kts with gusts to 30kts will continue behind the Arctic front at
least through early afternoon before calming down during the
evening. This will cause crosswind issues on any southeast-
northwest oriented runways.
Specifics for KSTL:
Bands of snow will affect Lambert for the next several hours.
While vsbys will likely stay in MVFR range for the majority of the
time, occasional heavier snow will likely cause the visibility to
drop to 2SM or below periodically. Radar presentation of the bands
of snow suggests that the drops in visibility will be brief when
they occur. Snow should taper off and end between 09Z and 11Z.
Still think MVFR ceilings between 2000-3000FT will hang around
into late morning or early afternoon, but drier air should allow
the ceilings to break up later in the day. Northwest winds
sustained at 15 to 20kts with gusts to 30kts will continue behind
the Arctic front at least through early afternoon before calming
down during the evening.
Carney
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...WIND CHILL ADVISORY from 8 AM to 10 PM CST Wednesday FOR
Crawford MO-St. Francois MO-Ste. Genevieve MO-Washington MO.
WIND CHILL ADVISORY from 6 AM Wednesday to 9 AM CST Thursday FOR
Audrain MO-Boone MO-Callaway MO-Cole MO-Franklin MO-
Gasconade MO-Jefferson MO-Lincoln MO-Marion MO-Moniteau MO-
Monroe MO-Montgomery MO-Osage MO-Pike MO-Ralls MO-Shelby MO-
St. Charles MO-St. Louis City MO-St. Louis MO-Warren MO.
WIND CHILL WARNING from 3 AM Wednesday to 9 AM CST Thursday FOR
Knox MO-Lewis MO.
IL...WIND CHILL ADVISORY from 8 AM to 10 PM CST Wednesday FOR
Randolph IL.
WIND CHILL ADVISORY from 6 AM Wednesday to 9 AM CST Thursday FOR
Bond IL-Calhoun IL-Clinton IL-Fayette IL-Greene IL-Jersey
IL-Macoupin IL-Madison IL-Marion IL-Monroe IL-Montgomery IL-
Pike IL-St. Clair IL-Washington IL.
WIND CHILL WARNING from 3 AM Wednesday to 9 AM CST Thursday FOR
Adams IL-Brown IL.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
908 PM MST TUE JAN 6 2015
.UPDATE...
TEMPERATURES FROM KBIL W WERE ALREADY FALLING THROUGH THE SINGLE
DIGITS THIS EVENING AND WERE EXCEEDING FORECAST LOWS IN SOME
AREAS. THUS HAVE LOWERED MIN TEMPERATURES FOR THIS REGION. FURTHER
E...TEMPERATURES WERE NOT FALLING AS QUICKLY...SO BUMPED LOWS UP A
FEW DEGREES.
THE ARCTIC FRONT WAS THROUGH MUCH OF THE FORECAST AREA THIS
EVENING INCLUDING INTO THE HIGHER ELEVATIONS. KBLX VAD WIND
PROFILE SHOWED THE FRONTAL DEPTH WAS 8000 FT. RAP SOUNDING STILL
INDICATED SOME DENDRITIC GROWTH UNDER THE SNOWBAND UP TO AROUND
800 MB. SOME FRONTOGENESIS WAS OCCURRING JUST BEHIND THE LEADING
EDGE OF THE BOUNDARY AND WAS COMBINING WITH UPSLOPE FLOW AND WEAK
Q-VECTOR CONVERGENCE TO GENERATE LIGHT SNOW. RADAR IMAGERY SHOWED
THE SNOW WAS OCCURRING FROM JUDITH GAP SE INTO SHERIDAN COUNTY
WITH SNOW AS FAR E AS KMLS. RADAR TRENDS HAD THE BAND SPREADING S
AND W WITH TIME. HAVE INCREASED POPS TO CATEGORICAL UNDER THE
BAND...AND RAISED POPS W INTO KLVM AND THE FOOTHILLS THROUGH 06Z
BASED ON ABOVE TRENDS. LOWERED POPS OVER THE FAR NE ZONES.
NUDGED POPS UP JUST A LITTLE AFTER 06Z TO COVER THE REST OF THE
EVENT. WED STILL LOOKED DRY. WILL MAKE NO CHANGES TO HEADLINES AND
WILL ADJUST WORDING AS APPROPRIATE IN THE STATEMENT. ARTHUR
&&
.SHORT TERM...VALID FOR WED AND THU...
STORM SYSTEM THAT HAS BROUGHT THE MULTI-DAY SNOW IS SLOWING
COMING TO AN END. THE ARCTIC FRONT HAS AGAIN SHIFTED AS FAR WEST
AS LIVINGSTON AND THE FOOTHILLS WHERE TEMPERATURES DROPPED FROM
ABOUT 50 TO 20 DEGREES IN 5 MINUTES. VAD WIND PROFILE HAS SHOWN
THE ARCTIC HAS DEEPENED ACROSS THE CENTRAL ZONES AS WELL WITH
NORTHEAST WINDS UP TO 8K FEET. SNOW THAT HAS BEEN OCCURRING ACROSS
NORTHEAST AND EASTERN MONTANA FOR MOST OF THE DAY CONTINUES TO
SLOWLY SHIFT SOUTHWEST AS THE RADAR HAS BEEN FILLING IN FROM
ROSEBUD COUNTY TO WHEATLAND AND STILLWATER COUNTIES. MOST OF THIS
LOOKS TO BE VERY LIGHT BUT THERE ARE A FEW POCKETS OF HEAVIER
ACTIVITY. HRRR MODEL DOES NOT SHOW THIS BAND OF SNOW MAKING IT TOO
FAR WEST OF BILLINGS. HAVE KEPT POPS IN THE CHANCE CATEGORY FROM
ABOUT COLUMBUS WESTWARD WITH LITTLE IF ANY ACCUMULATIONS. WILL
MAINTAIN LIKELY POPS ALONG AND EAST OF A ROUNDUP-BILLINGS-
SHERIDAN LINE WITH ADDITIONAL ACCUMULATIONS OF 1 TO 3
INCHES...ALTHOUGH IT LOOKS TO BE MORE IN THE 1-2 INCH RANGE AS
DYNAMICS ARE NOT AS STRONG AS WAS THE CASE YESTERDAY. MODELS
DECREASE THE SNOW SIGNIFICANTLY AFTER MIDNIGHT SO LOWERED POPS TO
JUST A CHANCE AFTER MIDNIGHT WITH ANY ACCUMULATIONS EXPECTED TO BE
BEFORE MIDNIGHT. AS THE ARCTIC SHIFTS EAST AGAIN LATE TONIGHT WITH
WARM AIR JUST ABOVE THE SURFACE CAN`T RULE OUT SOME ISOLATED
POCKETS OF FREEZING DRIZZLE AGAIN ACROSS OUR CENTRAL AND WESTERN
AREAS.
FOR WEDNESDAY INTO THURSDAY...WEDNESDAY WILL SEE A BREAK IN
ACTIVITY WITH DRY CONDITIONS PREVAILING ACROSS THE FORECAST AREA
WITH TEMPERATURES MODERATING. MODELS THEN BRING THE ARCTIC FRONT
BACK THROUGH THE FORECAST AREA THURSDAY RESULTING IN TEMPERATURES
FALLING DURING THE DAY WITH OVERNIGHT LOWS FRIDAY MORNING IN THE
SINGLE DIGITS ABOVE TO TEENS BELOW ZERO. THE FRONT WILL BRING
ANOTHER ROUND OF LIGHT SNOW TO THE AREA BUT DYNAMICS OVERALL ARE
MUCH WEAKER THAN THIS PAST SYSTEM SO ACCUMULATIONS LOOK TO BE MUCH
LIGHTER. HOOLEY
.LONG TERM...VALID FOR FRI...SAT...SUN...MON...TUE...
THE LATEST EXTENDED MODELS DO NOT SHOW ANY SIGNIFICANT CHANGES
FROM PREVIOUS RUNS...AND ARE STILL IN GOOD AGREEMENT.
STARTING FRIDAY THE WEST COAST RIDGE WILL SLOWLY PUSH EAST
...BEGINNING THE SLOW RETREAT OF THE ARCTIC AIR. THIS RETREAT
WILL CONTINUE THROUGH THE WEEKEND. THERE WILL CONTINUE TO BE A
DECENT TEMPERATURE SPREAD EAST TO WEST UNTIL THE ARCTIC AIR CLEARS
THE STATE. BY SUNDAY TEMPERATURES WILL BE MORE MILD COMPARED TO
THE THE PAST SEVERAL DAYS THROUGH REMAINING BELOW NORMAL BY ABOUT
10 DEGREES.
THE RIDGE WILL SLOWLY DEAMPLIFY AS A LOW MOVES INTO WESTERN
BRITISH COLUMBIA. A WEAK WAVE WILL DEVELOP OFF THIS LOW AND MOVE
ACROSS THE STATE SATURDAY NIGHT INTO SUNDAY. THIS WILL BRING
ANOTHER SHOT AT LIGHT SNOW. THERE IS SOME MODEL VARIABILITY IN THE
TRACK OF THE WAVE...WITH THE EC SHIFTING THE WEAK FORCING A LITTLE
EAST OF THE GFS SOLUTION. NEITHER SOLUTION HAS STRONG FORCING OR
MOISTURE....THUS EXPECTING AMOUNTS TO BE LIGHT. REIMER/HOOLEY
&&
.AVIATION...
MVFR TO IFR CONDITIONS WITH AREAS OF LOW CLOUDS AND LIGHT SNOW
ARE EXPECTED TO CONTINUE THROUGH THE EVENING OVER MUCH OF SOUTHERN
MT AND NORTH CENTRAL WY. CONDITIONS WILL IMPROVE GRADUALLY AFTER
06 UTC AS THE SNOW ENDS...BUT SOME AREAS OF LOW CLOUD WILL LIKELY
PERSIST INTO EARLY WEDNESDAY. EXPECT VFR WEATHER OVER THE WHOLE
AREA BY MIDDAY WEDNESDAY. GUSTY SW-W WINDS WILL DEVELOP ALONG THE
FOOTHILLS ON WEDNESDAY AS THE ARCTIC AIR RETREATS. THIS INCLUDES
KLVM WHERE GUSTS COULD REACH 30 KTS. JKL
&&
.PRELIMINARY POINT TEMP/POPS...
WED THU FRI SAT SUN MON TUE
-----------------------------------------------------------
BIL 000/035 024/025 902/011 004/020 011/024 011/029 016/030
81/B 13/S 21/B 12/J 22/J 11/B 01/B
LVM 008/044 026/033 008/026 019/035 019/034 020/036 021/034
51/N 01/B 21/B 12/J 22/J 11/B 11/B
HDN 000/028 016/026 907/012 901/020 005/023 004/028 013/030
90/E 13/S 20/B 11/B 22/J 11/B 00/B
MLS 910/018 013/021 914/002 909/012 904/015 002/023 011/027
60/B 23/S 10/U 11/B 12/J 10/B 01/B
4BQ 905/024 017/025 912/007 901/019 005/021 007/026 014/030
80/B 04/S 10/U 01/B 12/J 11/B 11/B
BHK 914/014 009/020 914/002 907/012 904/014 003/023 011/026
30/B 23/S 00/U 11/B 12/J 00/B 11/B
SHR 000/031 025/029 903/016 007/028 011/028 010/030 014/031
81/B 03/S 31/B 12/J 22/J 11/B 01/B
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...WINTER WEATHER ADVISORY IN EFFECT UNTIL 6 AM MST WEDNESDAY
FOR ZONES 28>33-35>38-42-57-58.
WINTER STORM WARNING IN EFFECT UNTIL 6 AM MST WEDNESDAY FOR
ZONE 63.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
316 AM MST WED JAN 7 2015
.SHORT TERM...(TODAY THROUGH TONIGHT )
ISSUED AT 314 AM MST WED JAN 7 2015
SHALLOW LYR OF ARCTIC AIR HAS MOVED ACROSS NERN CO WITH AREAS OF
VERY LIGHT SNOW WHICH HAS MIXED WITH LIGHT FREEZING DRIZZLE ALONG
THE FRONT RANGE. APPEARS THIS WILL CONTINUE THRU THE MID MORNING
HOURS BEFORE GRADUALLY ENDING BY LATE MORNING. IN THE FOOTHILLS AND
OVER THE PALMER DIVIDE CAMS SHOW QUITE A BIT OF DENSE FOG AS WELL
SO WILL EXTEND ADVISORY THRU MID MORNING. OVERALL AREAS OF
FREEZING DRIZZLE CLOSER TO THE FOOTHILLS WILL LIKELY LEAD TO SOME
ICY ROADS THRU THE MID MORNING HOURS SO WILL ISSUE AN ADVISORY FOR
THE MORNING COMMUTE.
FOR THIS AFTN SHOULD SEE DRY CONDITIONS OVER THE AREA HOWEVER AREAS
OF LOW CLOUDS WILL CONTINUE OVER PORTIONS OF NERN CO. WILL KEEP
HIGHS OVER MOST OF THE PLAINS IN THE 15 TO 20 DEGREE RANGE WITH MID
TO UPPER 20S TO AROUND THE DENVER AREA.
BY TONIGHT THE ARCTIC SFC HIGH WILL MOVE FM THE CNTRL PLAINS INTO
THE SRN PLAINS AS A SFC LEE TROUGH BEGINS TO DVLP ALONG THE FRONT
RANGE. AS A RESULT THE LOW LVL FLOW WILL BECOM MORE SSW OVER NERN
CO. LOW TEMPS WILL PROBABLY OCCUR EARLY IN THE EVENING AND THEN
STEADILY RISE OVERNIGHT EXCEPT POSSIBLY ALONG THE SOUTH PLATTE RIVER
VALLEY WHERE INVERSIONS MAY CONTINUE TO HOLD DUE TO LINGERING
SNOWPACK.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 314 AM MST WED JAN 7 2015
MAIN WEATHER FEATURE WILL BE ANOTHER ARCTIC FRONT POISED THE REACH
THE AREA LATE THURSDAY.
INCREASED DOWNSLOPE WARMING IN/NEAR THE FRONT RANGE WILL BRING A
WARMER DAY ON THURSDAY. HOWEVER...THE NEXT ARCTIC FRONT IS EXPECTED
TO REACH THE NORTHEAST PLAINS BY MID/LATE AFTERNOON. ANOTHER SURGE
OF MUCH COLDER AIR BEHIND THIS FRONT WILL PUSH ACROSS THE PLAINS
AND BACK INTO THE FOOTHILLS...SETTING UP ANOTHER ROUND OF LIGHT
SNOW OR FREEZING DRIZZLE...AND AREAS OF FOG. THIS TIME...THE
MOISTURE IS A LITTLE DEEPER THOUGH SO WE WILL SEE A BETTER CHANCE
OF SNOW WITH LIGHT ACCUMULATIONS POSSIBLE. THERE IS STILL A
REASONABLE THREAT OF FREEZING DRIZZLE ESPECIALLY IN THE THURSDAY
EVENING HOURS BEFORE MOISTURE DEEPENS SUFFICIENTLY FOR
SEEDER/FEEDER INTERACTION. WILL BOOST POPS MOST OF THE PLAINS AND
FOOTHILLS FOCUSING ON THE FRONT RANGE I-25 CORRIDOR FOR THURSDAY
NIGHT CONSIDERING POTENTIAL FOR DEEPER MOISTURE AND UPSLOPE
COMPONENT. MOST OF THE HIGHER MOUNTAINS AND HIGH VALLEYS SHOULD
REMAIN DRY WITH LACK OF DEEPER MOISTURE IN THOSE LOCALES.
FRIDAY WILL LIKELY BE COLDER IN A SIMILAR SETUP TO TODAY...SO
LOWERED HIGH TEMPS A COUPLE DEGREES. THEN SATURDAY SHOULD SEE
BETTER DOWNSLOPE FLOW SO WILL KEEP THE WEATHER ROLLER COASTER
OPERATING WITH WARMER TEMPERATURES AND DRY CONDITIONS. SNOW
COVERED AREAS WILL STILL BE SLOW TO WARM THOUGH AS EVIDENCED BY
HIGHS OBSERVED OVER THE LAST FEW DAYS.
THE NEXT WEATHER MAKER MAY REACH THE AREA BY MONDAY OR TUESDAY SO
THE GOING FORECAST OF SOMEWHAT COOLER TEMPERATURES AND CHANCE OF
SNOW LOOKS GOOD. THIS SYSTEM COULD LINGER INTO THE MID PART OF
NEXT WEEK AS ITS CUT OFF FROM THE MAIN NORTHERN BRANCH ENERGY.
&&
.AVIATION...(FOR THE TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 314 AM MST WED JAN 7 2015
WEAK UPSLOPE FLOW WILL CONTINUE TO PRODUCE IFR TO LIFR CONDITIONS
THRU MID MORNING AT THE AIRPORTS. AREAS OF LIGHT FREEZING
DRIZZLE/LIGHT SNOW WILL ALSO CONTINUE WITH SOME MINOR GLAZE
POSSIBLE. IFR CONDITIONS MAY LINGER THRU 18Z BUT CONDITIONS SHOULD
MAY IMPROVE BY EARLY AFTN. HOWEVER IF DENVER CYCLONE STAYS SOUTH OF
DIA AS SHOWN BY HRRR AND RAP THEN THE LOWER CLOUDS COULD AFFECT BJC
AND DIA THRU LATE AFTN.
AS FAR AS WINDS BOTH HRRR AND RAP SHOW A DENVER CYCLONE STAYING
SOUTH OF DIA THRU THE AFTN WITH MAINLY ELY WINDS WHICH MAY BECOME
MORE SELY AFT 21Z. FOR THIS EVENING RAP SHOWS SOME POTENTIAL FOR
IFR CONDITIONS EARLY THIS EVENING BEFORE DRAINAGE WINDS DEVELOP BY
03Z.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 9 AM MST THIS MORNING FOR
COZ038>040.
DENSE FOG ADVISORY UNTIL 9 AM MST THIS MORNING FOR COZ035-036-
041.
&&
$$
SHORT TERM...RPK
LONG TERM...BARJENBRUCH
AVIATION...RPK
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
952 AM EST WED JAN 7 2015
.UPDATE...
THE NEAR TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 438 AM EST WED JAN 7 2015
EXTREMELY COLD AIR WILL CONTINUE TO POUR INTO THE AREA TODAY THROUGH
EARLY THURSDAY AS A STRONG COLD DOME OF HIGH PRESSURE DROPS INTO THE
REGION. AREAS OF BLOWING SNOW CAN BE EXPECTED WITH WIND CHILLS WELL
BELOW ZERO AS WINDS INCREASE EVEN MORE TODAY. AN AREA OF LIGHT SNOW
SHOWERS WILL DROP SOUTH OF THE FORECAST AREA BY LATER THIS MORNING.
MEANWHILE SOME LAKE EFFECT SNOW SHOWERS ACROSS THE NORTHEAST ARE
POSSIBLE BY EARLY IN THE DAY. DRY WEATHER WILL PREVAIL FOR THE END
OF THE WEEK AND MUCH OF THE WEEKEND AS TEMPERATURES BEGIN TO
MODERATE SLIGHTLY...BUT REMAIN BELOW NORMAL THROUGH THE MAJORITY OF
THE FORECAST PERIOD. CHANCES FOR SNOW WILL APPEAR AGAIN AT THE START
OF NEXT WEEK DUE TO AN UPPER LEVEL SYSTEM MOVING THROUGH THE AREA.
&&
.NEAR TERM /LATE MORNING THROUGH THE REST OF TODAY/...
ISSUED AT 923 AM EST WED JAN 7 2015
UPDATE...
EARLY MORNING SNOW SHOWERS HAVE TAPERED OFF OVER SOUTHERN PORTIONS
OF CENTRAL INDIANA. ELSEWHERE...LIGHT LAKE EFFECT SNOW SHOWERS
COULD MAKE THERE WAY INTO THE NORTHEASTERN COUNTIES TODAY...BUT
THE MAIN THREAT WILL BE BLOWING AND DRIFTING SNOW OVER THE
NORTHERN COUNTIES AND THE FRIGID WIND CHILLS OVER ALL OF CENTRAL
INDIANA. STRONG NORTHWEST WINDS WITH SUSTAINED SPEEDS OF 15 TO 20
MPH AND GUSTS UP TO 30 MPH WILL RESULT IN WIND CHILLS FROM -15 TO
-25 DEGREES. CURRENTLY...TEMPS ACROSS THE AREA ARE GENERALLY IN
THE LOW SINGLE DIGITS WITH WIND CHILLS FROM ZERO TO 10 DEGREES
BELOW ZERO. UPDATED GRIDS HAVE BEEN SENT.
PREVIOUS DISCUSSION...
A DISTURBANCE OVER CENTRAL ILLINOIS WHICH NONE OF THE GUIDANCE
PICKED UP ON EXCEPT THE SREF AND HRRR MOVED INTO CENTRAL INDIANA
VERY EARLY THIS MORNING AND STARTED PRODUCING SNOW AT LAF AND
CONTINUES TO DO SO AS IT DROPS SOUTH OVER THE FORECAST
AREA...CURRENTLY STILL SNOWING HERE AT IND BUT SHOULD END AROUND 6
AM. HAD TO UPDATE THE MORNING FORECAST TO ACCOUNT FOR THESE
SCATTERED SNOW SHOWERS. SREF AND HRRR IN DISAGREEMENT ABOUT WHEN THE
SNOW WILL EXIT THE AREA. THE HRRR HAS THE ACTIVITY DISSIPATING OR
SOUTH OF THE AREA BY 12Z...WHILE THE SREF DOES NOT MOVE THE SNOW OUT
OF THE AREA UNTIL 15Z. LEANED CLOSER TO THE SREF SOLUTION BASED ON
LATEST RADAR TRENDS. SO THERE WILL BE SCATTERED CHANCES FOR SNOW
SHOWERS IN THE FORECAST FROM AROUND THE I-70 CORRIDOR AND SOUTHWARD
THROUGH EARLY THIS MORNING. LITTLE TO NO SNOW ACCUMULATION IS
EXPECTED.
ELSEWHERE...LAKE EFFECT SNOW OFF THE SOUTHEASTERN SHORE OF LAKE
MICHIGAN IS SLOWLY MAKING ITS WAY SOUTH TOWARD THE NORTHEAST CORNER
OF THE FORECAST AREA. LEFT IN LOW CHANCES FOR SNOW SHOWERS FROM LATE
THIS MORNING THROUGH THE AFTERNOON HOURS BEFORE THE LAKE EFFECT
MACHINE LETS UP EARLY THIS EVENING.
NOW WE TURN TO THE BIG STORY OF THE DAY AND NEXT 24+ HOURS: THE
DANGEROUSLY COLD WIND CHILLS. EARLY THIS MORNING AFTER COMPLETING
MOST OF THE FORECAST...OPTED TO MAKE ONE ADJUSTMENT TO THE
HEADLINES. REALIZED THAT THE NORTHERN HALF OF THE AREA WHICH WAS
THEN UNDER A WIND CHILL ADVISORY WOULD BE UPGRADED TO A WARNING BY
8AM...A MERE COUPLE OF HOURS. AND SINCE THE WINDS WILL ONLY GROW
STRONGER THROUGH EARLY THIS MORNING AND TEMPERATURES WILL PLUMMET
DECIDED TO DO THE UPGRADE EARLY AND GO WITH A WARNING NOW.
CONDITIONS ARE NOT AT THIS CRITERIA YET BUT WILL BE SHORTLY THIS
MORNING. OTHERWISE LEFT THE REST OF THE HEADLINES INTACT...INCLUDING
THE ADVISORY FOR THE SOUTHERN HALF OF THE CWA...WHICH CAN BE FOUND
UNDER THE PRODUCT ID INDWSWIND. BOTH HEADLINES ARE SET TO EXPIRE AT
10 AM THURSDAY MORNING.
THOSE STRONG NORTHWEST WINDS MENTIONED ABOVE MAY ALSO CAUSE BLOWING
AND DRIFTING OF SNOW...ESPECIALLY FOR LOCATIONS ACROSS THE NORTHERN
HALF OF THE AREA WHERE MORE SNOW WAS RECEIVED YESTERDAY.
AS FOR TEMPERATURES CENTRAL INDIANA IS PROBABLY LOOKING AT THE
WARMEST TEMPS OF THE DAY RIGHT NOW. TEMPERATURE WILL PLUMMET AS
MENTIONED SO THE HIGH TEMPERATURE BETWEEN 12Z TODAY TO 00Z THU WILL
ONLY BE IN THE SINGLE DIGITS...RANGING FROM 0 (NW) TO NEAR 10 ACROSS
THE FAR SOUTH. BLEND OF GUIDANCES SEEMED TO DO A GREAT JOB.
&&
.SHORT TERM /TONIGHT THROUGH FRIDAY NIGHT/...
ISSUED AT 438 AM EST WED JAN 7 2015
TEMPERATURES REMAIN THE MAJOR FOCUS IN THE SHORT TERM WITH A
BITTERLY COLD AIR MASS IN PLACE ACROSS THE AREA. WILL CONTINUE TO
UNDERCUT MODEL NUMBERS...ESPECIALLY OVER THE SNOWPACK...OWING TO
MODEL TENDENCIES TO UNDERESTIMATE THE MAGNITUDE OF ARCTIC OUTBREAKS.
THIS RESULTS IN MIN TEMPS TONIGHT BELOW ZERO ACROSS ALL OF
CENTRAL INDIANA...WITH LOWS AROUND -10 OR BELOW ACROSS THE NORTHERN
HALF. TEMPERATURES WILL BEGIN TO MODERATE SLIGHTLY THURSDAY BUT
REMAIN QUITE COLD. SOME AREAS OF CENTRAL INDIANA...ESPECIALLY ACROSS
THE NORTH...MAY NOT SEE THE 20 DEGREE MARK UNTIL LATE IN THE WEEKEND.
APPARENT TEMPERATURES WILL CONTINUE TO WORSEN TONIGHT AS WINDS STAY
STRONG AND STEADY. CURRENT WIND CHILL WARNING ACROSS THE NORTH AND
ADVISORY ACROSS THE SOUTH HANDLES THIS WELL AND WILL REMAIN
UNCHANGED. EXPIRATION BY 10AM THURSDAY MORNING STILL LOOKS GOOD THIS
FORECAST ISSUANCE.
BY THURSDAY NIGHT A WEAK LITTLE SYSTEM OVER THE GREAT LAKES MAY
PRODUCE CHANCES FOR SCATTERED FLURRIES ACROSS THE NORTH. NO
ACCUMULATING SNOW IS EXPECTED DURING THIS TIME. TEMPERATURES BEGIN
TO SLOWLY MODERATE INTO FRIDAY HOWEVER STILL VERY COLD AND BELOW
NORMAL WITH HIGHS ONLY IN THE TEENS.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
ISSUED AT 438 AM EST WED JAN 7 2015
HIGH PRESSURE OVER THE AREA TO BEGIN THE LONG TERM. THE HIGH MOVES
OFF TO THE EAST ALLOWING WARMER AIR TO MAKE ITS WAY INTO CENTRAL
INDIANA. ANOTHER SURFACE HIGH ATTEMPTS TO BUILD IN FROM THE
NORTHWEST...BUT MODELS DIFFER ON HOW QUICKLY THIS OCCURS. GFS SHOWS
A FAIRLY QUICK TRANSITION FROM ONE HIGH TO THE NEXT BUT THE ECMWF
DEVELOPS A WEAK FRONTAL ZONE BETWEEN THE HIGHS AND BRINGS
PRECIPITATION INTO THE AREA FROM SUNDAY NIGHT ON. GIVEN THE
UNCERTAINTY KEPT THE SLIGHT TO LOW CHANCE POPS FROM THE
INITIALIZATION FROM SUNDAY NIGHT ON...BUT SHOULD NOTE THAT COULD
JUST AS EASILY SEE DRY WEATHER AS WET WEATHER FOR THE BEGINNING OF
THE WORK WEEK.
&&
.AVIATION /DISCUSSION FOR 071200Z TAF ISSUANCE/...
ISSUED AT 559 AM EST WED JAN 7 2015
SNOW SHOWERS SHOULD BE SOUTH OF ALL SITES BUT KBMG BY ISSUANCE TIME.
EXPECT VFR CONDITIONS AT KLAF. AT OTHER SITES THINK CLOUDS WILL
SCATTER OUT FAIRLY QUICKLY BUT SOME UNCERTAINTY THERE AS AT THE
SOUTHWARD MOVEMENT OF THE CLOUD DECK HAS SLOWED A BIT OVER THE PAST
FEW HOURS. AT KBMG SHOULD SEE SNOW BANDS HANG AROUND UNTIL 12-13Z
AND HAVE SAME CONCERNS ABOUT MVFR CEILINGS HANGING AROUND THERE. MAY
INCLUDE A TEMPO GROUP OF MVFR CEILINGS FOR A FEW HOURS THIS MORNING
AT ALL SITES BUT KLAF TO COVER THIS POTENTIAL. ALSO THERE IS SOME
POTENTIAL FOR BLOWING SNOW TODAY AS WINDS WILL GUST 25-35 KTS OUT OF
THE NORTHWEST THIS MORNING AND 20-30 KTS THIS AFTERNOON BUT RIGHT
NOW THESE SAME CONDITIONS ARE OCCURRING AT KLAF AND IT IS NOT
RESULTING IN ANY REDUCTIONS IN VISIBILITY SO WILL LIKELY LEAVE OUT
OF TAFS. WIND GUSTS SHOULD DROP OFF TONIGHT BUT WINDS WILL REMAIN
5-12 KTS AND WILL SHIFT FROM NORTHWESTERLY TO SOUTHWESTERLY DURING
THE OVERNIGHT HOURS.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
WIND CHILL ADVISORY UNTIL 10 AM EST THURSDAY FOR INZ051>057-
060>065-067>072.
WIND CHILL WARNING UNTIL 10 AM EST THURSDAY FOR INZ021-028>031-
035>049.
&&
$$
SYNOPSIS...SMF
NEAR TERM...SMF/TDUD
SHORT TERM...SMF
LONG TERM....CP
AVIATION...CP
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSINDIANAPOLIS
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
602 AM EST WED JAN 7 2015
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 438 AM EST WED JAN 7 2015
EXTREMELY COLD AIR WILL CONTINUE TO POUR INTO THE AREA TODAY THROUGH
EARLY THURSDAY AS A STRONG COLD DOME OF HIGH PRESSURE DROPS INTO THE
REGION. AREAS OF BLOWING SNOW CAN BE EXPECTED WITH WIND CHILLS WELL
BELOW ZERO AS WINDS INCREASE EVEN MORE TODAY. AN AREA OF LIGHT SNOW
SHOWERS WILL DROP SOUTH OF THE FORECAST AREA BY LATER THIS MORNING.
MEANWHILE SOME LAKE EFFECT SNOW SHOWERS ACROSS THE NORTHEAST ARE
POSSIBLE BY EARLY IN THE DAY. DRY WEATHER WILL PREVAIL FOR THE END
OF THE WEEK AND MUCH OF THE WEEKEND AS TEMPERATURES BEGIN TO
MODERATE SLIGHTLY...BUT REMAIN BELOW NORMAL THROUGH THE MAJORITY OF
THE FORECAST PERIOD. CHANCES FOR SNOW WILL APPEAR AGAIN AT THE START
OF NEXT WEEK DUE TO AN UPPER LEVEL SYSTEM MOVING THROUGH THE AREA.
&&
.NEAR TERM /EARLY THIS MORNING THROUGH THE REST OF TODAY/...
ISSUED AT 438 AM EST WED JAN 7 2015
A DISTURBANCE OVER CENTRAL ILLINOIS WHICH NONE OF THE GUIDANCE
PICKED UP ON EXCEPT THE SREF AND HRRR MOVED INTO CENTRAL INDIANA
VERY EARLY THIS MORNING AND STARTED PRODUCING SNOW AT LAF AND
CONTINUES TO DO SO AS IT DROPS SOUTH OVER THE FORECAST
AREA...CURRENTLY STILL SNOWING HERE AT IND BUT SHOULD END AROUND 6
AM. HAD TO UPDATE THE MORNING FORECAST TO ACCOUNT FOR THESE
SCATTERED SNOW SHOWERS. SREF AND HRRR IN DISAGREEMENT ABOUT WHEN THE
SNOW WILL EXIT THE AREA. THE HRRR HAS THE ACTIVITY DISSIPATING OR
SOUTH OF THE AREA BY 12Z...WHILE THE SREF DOES NOT MOVE THE SNOW OUT
OF THE AREA UNTIL 15Z. LEANED CLOSER TO THE SREF SOLUTION BASED ON
LATEST RADAR TRENDS. SO THERE WILL BE SCATTERED CHANCES FOR SNOW
SHOWERS IN THE FORECAST FROM AROUND THE I-70 CORRIDOR AND SOUTHWARD
THROUGH EARLY THIS MORNING. LITTLE TO NO SNOW ACCUMULATION IS
EXPECTED.
ELSEWHERE...LAKE EFFECT SNOW OFF THE SOUTHEASTERN SHORE OF LAKE
MICHIGAN IS SLOWLY MAKING ITS WAY SOUTH TOWARD THE NORTHEAST CORNER
OF THE FORECAST AREA. LEFT IN LOW CHANCES FOR SNOW SHOWERS FROM LATE
THIS MORNING THROUGH THE AFTERNOON HOURS BEFORE THE LAKE EFFECT
MACHINE LETS UP EARLY THIS EVENING.
NOW WE TURN TO THE BIG STORY OF THE DAY AND NEXT 24+ HOURS: THE
DANGEROUSLY COLD WIND CHILLS. EARLY THIS MORNING AFTER COMPLETING
MOST OF THE FORECAST...OPTED TO MAKE ONE ADJUSTMENT TO THE
HEADLINES. REALIZED THAT THE NORTHERN HALF OF THE AREA WHICH WAS
THEN UNDER A WIND CHILL ADVISORY WOULD BE UPGRADED TO A WARNING BY
8AM...A MERE COUPLE OF HOURS. AND SINCE THE WINDS WILL ONLY GROW
STRONGER THROUGH EARLY THIS MORNING AND TEMPERATURES WILL PLUMMET
DECIDED TO DO THE UPGRADE EARLY AND GO WITH A WARNING NOW.
CONDITIONS ARE NOT AT THIS CRITERIA YET BUT WILL BE SHORTLY THIS
MORNING. OTHERWISE LEFT THE REST OF THE HEADLINES INTACT...INCLUDING
THE ADVISORY FOR THE SOUTHERN HALF OF THE CWA...WHICH CAN BE FOUND
UNDER THE PRODUCT ID INDWSWIND. BOTH HEADLINES ARE SET TO EXPIRE AT
10 AM THURSDAY MORNING.
THOSE STRONG NORTHWEST WINDS MENTIONED ABOVE MAY ALSO CAUSE BLOWING
AND DRIFTING OF SNOW...ESPECIALLY FOR LOCATIONS ACROSS THE NORTHERN
HALF OF THE AREA WHERE MORE SNOW WAS RECEIVED YESTERDAY.
AS FOR TEMPERATURES CENTRAL INDIANA IS PROBABLY LOOKING AT THE
WARMEST TEMPS OF THE DAY RIGHT NOW. TEMPERATURE WILL PLUMMET AS
MENTIONED SO THE HIGH TEMPERATURE BETWEEN 12Z TODAY TO 00Z THU WILL
ONLY BE IN THE SINGLE DIGITS...RANGING FROM 0 (NW) TO NEAR 10 ACROSS
THE FAR SOUTH. BLEND OF GUIDANCES SEEMED TO DO A GREAT JOB.
&&
.SHORT TERM /TONIGHT THROUGH FRIDAY NIGHT/...
ISSUED AT 438 AM EST WED JAN 7 2015
TEMPERATURES REMAIN THE MAJOR FOCUS IN THE SHORT TERM WITH A
BITTERLY COLD AIR MASS IN PLACE ACROSS THE AREA. WILL CONTINUE TO
UNDERCUT MODEL NUMBERS...ESPECIALLY OVER THE SNOWPACK...OWING TO
MODEL TENDENCIES TO UNDERESTIMATE THE MAGNITUDE OF ARCTIC OUTBREAKS.
THIS RESULTS IN MIN TEMPS TONIGHT BELOW ZERO ACROSS ALL OF
CENTRAL INDIANA...WITH LOWS AROUND -10 OR BELOW ACROSS THE NORTHERN
HALF. TEMPERATURES WILL BEGIN TO MODERATE SLIGHTLY THURSDAY BUT
REMAIN QUITE COLD. SOME AREAS OF CENTRAL INDIANA...ESPECIALLY ACROSS
THE NORTH...MAY NOT SEE THE 20 DEGREE MARK UNTIL LATE IN THE WEEKEND.
APPARENT TEMPERATURES WILL CONTINUE TO WORSEN TONIGHT AS WINDS STAY
STRONG AND STEADY. CURRENT WIND CHILL WARNING ACROSS THE NORTH AND
ADVISORY ACROSS THE SOUTH HANDLES THIS WELL AND WILL REMAIN
UNCHANGED. EXPIRATION BY 10AM THURSDAY MORNING STILL LOOKS GOOD THIS
FORECAST ISSUANCE.
BY THURSDAY NIGHT A WEAK LITTLE SYSTEM OVER THE GREAT LAKES MAY
PRODUCE CHANCES FOR SCATTERED FLURRIES ACROSS THE NORTH. NO
ACCUMULATING SNOW IS EXPECTED DURING THIS TIME. TEMPERATURES BEGIN
TO SLOWLY MODERATE INTO FRIDAY HOWEVER STILL VERY COLD AND BELOW
NORMAL WITH HIGHS ONLY IN THE TEENS.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
ISSUED AT 438 AM EST WED JAN 7 2015
HIGH PRESSURE OVER THE AREA TO BEGIN THE LONG TERM. THE HIGH MOVES
OFF TO THE EAST ALLOWING WARMER AIR TO MAKE ITS WAY INTO CENTRAL
INDIANA. ANOTHER SURFACE HIGH ATTEMPTS TO BUILD IN FROM THE
NORTHWEST...BUT MODELS DIFFER ON HOW QUICKLY THIS OCCURS. GFS SHOWS
A FAIRLY QUICK TRANSITION FROM ONE HIGH TO THE NEXT BUT THE ECMWF
DEVELOPS A WEAK FRONTAL ZONE BETWEEN THE HIGHS AND BRINGS
PRECIPITATION INTO THE AREA FROM SUNDAY NIGHT ON. GIVEN THE
UNCERTAINTY KEPT THE SLIGHT TO LOW CHANCE POPS FROM THE
INITIALIZATION FROM SUNDAY NIGHT ON...BUT SHOULD NOTE THAT COULD
JUST AS EASILY SEE DRY WEATHER AS WET WEATHER FOR THE BEGINNING OF
THE WORK WEEK.
&&
.AVIATION /DISCUSSION FOR 071200Z TAF ISSUANCE/...
ISSUED AT 559 AM EST WED JAN 7 2015
SNOW SHOWERS SHOULD BE SOUTH OF ALL SITES BUT KBMG BY ISSUANCE TIME.
EXPECT VFR CONDITIONS AT KLAF. AT OTHER SITES THINK CLOUDS WILL
SCATTER OUT FAIRLY QUICKLY BUT SOME UNCERTAINTY THERE AS AT THE
SOUTHWARD MOVEMENT OF THE CLOUD DECK HAS SLOWED A BIT OVER THE PAST
FEW HOURS. AT KBMG SHOULD SEE SNOW BANDS HANG AROUND UNTIL 12-13Z
AND HAVE SAME CONCERNS ABOUT MVFR CEILINGS HANGING AROUND THERE. MAY
INCLUDE A TEMPO GROUP OF MVFR CEILINGS FOR A FEW HOURS THIS MORNING
AT ALL SITES BUT KLAF TO COVER THIS POTENTIAL. ALSO THERE IS SOME
POTENTIAL FOR BLOWING SNOW TODAY AS WINDS WILL GUST 25-35 KTS OUT OF
THE NORTHWEST THIS MORNING AND 20-30 KTS THIS AFTERNOON BUT RIGHT
NOW THESE SAME CONDITIONS ARE OCCURRING AT KLAF AND IT IS NOT
RESULTING IN ANY REDUCTIONS IN VISIBILITY SO WILL LIKELY LEAVE OUT
OF TAFS. WIND GUSTS SHOULD DROP OFF TONIGHT BUT WINDS WILL REMAIN
5-12 KTS AND WILL SHIFT FROM NORTHWESTERLY TO SOUTHWESTERLY DURING
THE OVERNIGHT HOURS.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
WIND CHILL ADVISORY UNTIL 10 AM EST THURSDAY FOR INZ051>057-
060>065-067>072.
WIND CHILL WARNING UNTIL 10 AM EST THURSDAY FOR INZ021-028>031-
035>049.
&&
$$
SYNOPSIS...SMF
NEAR TERM...SMF
SHORT TERM...SMF
LONG TERM....CP
AVIATION...CP
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSINDIANAPOLIS
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS TAUNTON MA
1255 PM EST WED JAN 7 2015
.SYNOPSIS...
AN ARCTIC FRONT SWEEPS SOUTHERN NEW ENGLAND TODAY...BRINGING WITH
IT A CHANCE OF SNOW SQUALLS. BEHIND THIS FRONT...BLUSTERY AND
BITTERLY COLD CONDITIONS FOLLOW INTO THURSDAY. A BRIEF PERIOD OF
LIGHT SNOW IS LIKELY LATE THURSDAY NIGHT INTO FRIDAY FRIDAY AHEAD
OF ANOTHER COLD FRONT. THERE IS ALSO A CONCERN FOR STRONG...TO
PERHAPS EVEN DAMAGING...WIND GUSTS ON FRIDAY ACROSS THE SOUTHEAST
NEW ENGLAND COAST. OTHERWISE...MAINLY COLD AND DRY WEATHER EXPECT
THIS WEEKEND INTO EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
1 PM UPDATE...
PUFFY CUMULUS CLOUDS OUTSIDE INDICATIVE OF JUST HOW UNSTABLE THE
ENVIRONMENT IS BECOMING AS ARCTIC AIR IS DRIVING S ACROSS THE
WARMER TERRAIN SUBSEQUENT OF ABUNDANT SUNSHINE AND MOSTLY CLEAR
CONDITIONS EARLIER TODAY.
WEATHER: CONSISTENT HRRR SIGNALS AND LOOKING UPSTREAM DECENT LINE
APPROACHING OF SNOW SQUALLS ON THE LEADING EDGE OF THE ARCTIC COLD
FRONT. SPECIAL WEATHER STATEMENT ISSUED. SNOW-SQUALL ACTIVITY TO
PUSH INTO THE CT-RIVER VALLEY AFTER 1 PM...WORCESTER BY 3 PM...AND
THE BOSTON-PROVIDENCE CORRIDOR BY 4 PM. WITH SNOW-SQUALL ACTIVITY
EXPECT NEAR WHITE-OUT CONDITIONS WITH REDUCED VISIBILITIES DOWN TO
LESS THAN ONE-HALF MILE. SNOW WILL ACCUMULATE IMMEDIATELY UPWARDS
OF AN INCH. EXPECT ACCOMPANYING WINDS GUSTING AROUND 35 MPH. WITH
SUCH BURSTS OF SNOW AND WIND...EXPECT HAZARDOUS TRAVEL CONDITIONS.
MOTORISTS SHOULD BE CAUTIOUS AND TRAVEL AT SLOWER SPEEDS WHEN
ENCOUNTERING SNOW-SQUALL ACTIVITY.
WIND GUSTS: EVALUATING UPSTREAM AND NEAR THE WATERS...GUSTS UP TO
40 MPH HAVE BEEN OBSERVED. UTILIZED A MIX-DOWN TOOL BASED ON THE
NAM / RAP THERMAL PROFILES WHICH SUBSEQUENTLY UPPED THE WIND GUSTS
FOR THE LATE-AFTERNOON INTO EVENING PERIOD. NOW EXPECTING MAX WIND
GUSTS OF 35 TO 45 MPH ACROSS MUCH OF THE INTERIOR...WITH GUSTS 40
TO 45 MPH OVER THE WATERS...A NUDGE UP FROM THE PRIOR FORECAST.
SUSTAINED WINDS: BLENDED NAM/WRF/RAP/HRRR GUIDANCE HALVING IT
WITH A CONSENSUS OF MOS-GUIDANCE WHICH YIELDED FASTER SUSTAINED
FLOW THAN PREVIOUSLY FORECAST...AS WELL AS BETTER AGREEMENT WITH
PRESENT OBSERVATIONS. MAX SUSTAINED WINDS FORECAST 20 TO 25 MPH
ACROSS THE INTERIOR...25 TO 35 MPH OVER THE WATERS.
E-CAPE: AS THE ARCTIC COLD FRONT PUSHES OFFSHORE...FEEL THE WIND
TRAJECTORY MORE W WILL LIMIT SNOW POTENTIAL OVER THE E-CAPE. IT
APPEAR HEAVIEST SNOW WILL OCCUR OFFSHORE...BUT STILL CAN NOT RULE
OUT ACCUMULATIONS OF 1-2 INCHES FROM PROVINCETOWN TO CHATHAM. AT
THIS TIME...LOW RISK OF WINTER WEATHER ADVISORIES.
TEMPERATURES / DEWPOINTS: STILL LEANED ON THE COLDER SIDE OF
GUIDANCE WITH A BLEND OF THE NAM / MET WITH GREATER WEIGHT LEANED
ONTO THE MET GUIDANCE. HIGHS ONLY GETTING INTO THE LOW- TO MID-20S
WITH UPPER-TEENS ACROSS THE HIGHER TERRAIN. COUPLED WITH THE WINDS
BACKING NW BEHIND THE FRONT...COLDEST WIND CHILL VALUES TOWARDS
DUSK WITH READINGS SEVERAL DEGREES BELOW ZERO FOR THE HIGH TERRAIN
WITH SINGLE DIGITS ABOVE ZERO ELSEWHERE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
*** BITTERLY COLD CONDITIONS ANTICIPATED TONIGHT THROUGH THURSDAY
MORNING...WITH WIND CHILL VALUES FALLING AS LOW AS 30 BELOW ZERO
FOR THURSDAY MORNING ***
TONIGHT...
THE CORE OF THE ARCTIC AIR ARRIVES TONIGHT. NOT EXPECTING ANY
CHANGES TO THE EXISTING WIND CHILL HEADLINES. THINKING LATEST
GUIDANCE IS NOT HANDLING THE MAGNITUDE OF THE ARCTIC AIR WELL...
SO UNDERCUT THE LATEST GUIDANCE.
WILL STILL BE CONTENDING WITH OCEAN-INDUCED STRATUS AND SNOW
ACROSS THE OUTER CAPE AND NANTUCKET. AS MENTIONED EARLIER...THE
STORM TOTAL SNOWFALL FORECAST CALLS FOR 1-2 INCHES AND FEEL
COMFORTABLE WITH THIS FORECAST WITH THE DRIER ARCTIC AIRMASS.
THURSDAY...
DANGEROUS AND BITTERLY COLD WIND CHILLS BETWEEN 15 AND 30 BELOW ZERO
WILL CONTINUE INTO MID MORNING. THERE WILL BE SOME RELIEF BY
AFTERNOON AS 850 MB TEMPERATURES RISE TO NEAR -16C...BUT IT STILL
WILL BE VERY COLD AND WELL BELOW NORMAL. AFTERNOON HIGHS SHOULD
RECOVER INTO THE UPPER TEENS TO AROUND 20 FOR MOST LOCATIONS UNDER
PARTLY TO MOSTLY SUNNY SKIES.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
* A DUSTING TO 1 INCH OF SNOW LIKELY FRIDAY
* STRONG TO EVEN DAMAGING WINDS FRIDAY FOR SE NEW ENGLAND COAST
* MAINLY DRY AND COLD THIS WEEKEND
UPPER LEVEL BLOCKING FORCES THE POLAR JET SOUTH RESULTING IN
TEMPERATURES WELL BELOW NORMAL THROUGH THE WEEKEND. THEN A STRONG
SURFACE HIGH SETS UP ACROSS EASTERN CANADA LIKELY KEEPING TEMPS
BELOW NORMAL. THERE IS POTENTIAL FOR SOME EFFECTS FROM A STORM
PASSING TO OUR SOUTH EARLY NEXT WEEK. BUT EXPECT THE BULK OF THE
STORM...OR POSSIBLY THE ENTIRE STORM WILL STAY WELL TO OUR SOUTH.
PLENTY OF TIME FOR THIS TO RESOLVE AS ITS NEARLY A WEEK AWAY.
THURSDAY NIGHT AND FRIDAY...A PERIOD OF LIGHT SNOW IS POSSIBLE AS
TEMPERATURES WARM AND A COLD FRONT APPROACHES SOUTHERN NEW ENGLAND.
THIS WILL BE SIMILAR TO YESTERDAYS SNOW WITH A DUSTING TO PERHAPS AN
INCH OF SNOW EXPECTED.
THE LARGER CONCERN IS THE POTENTIAL FOR STRONG TO DAMAGING WINDS
ALONG THE SOUTHEAST COAST OF NEW ENGLAND. A STRONG SOUTHWESTERLY
LOW LEVEL JET DEVELOPS OVER THIS REGION AS THE WARMER AIR FLOWS OVER
THE REGION. WHILE THIS SCENARIO USUALLY DOES NOT ALLOW THE STRONGER
WINDS TO MIX DOWN THE TEMPERATURES ALOFT ARE QUITE COLD AND WARMER
AIR AT THE SURFACE WILL ELIMINATE THE INVERSION OVER SOUTHEAST MASS.
WILL NEED AT LEAST A WIND ADVISORY FOR THE COASTAL ZONES OF
SOUTHEAST MASS. THERE IS POTENTIAL THAT WINDS WILL BE STRONG ENOUGH
TO NECESSITATE A HIGH WIND WARNING...PARTICULARLY FOR THE ISLANDS.
SATURDAY AND SUNDAY...HIGH PRESSURE PASSES SOUTH OF SOUTHERN NEW
ENGLAND...BRINGING COLDER AIR BACK INTO THE REGION. EXPECT BELOW
NORMAL TEMPERATURES.
MONDAY AND TUESDAY...ZONAL FLOW WILL LIKELY KEEP A COASTAL STORM
WELL TO OUR SOUTH. HOWEVER...THERE IS POTENTIAL FOR IT TO GRAZE OUR
SOUTHERN ZONES WITH SOME LIGHT SNOW. IN ADDITION...STRONG HIGH
PRESSURE IN QUEBEC WILL KEEP TEMPERATURES BELOW NORMAL.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH THURSDAY/...
18Z UPDATE...
LINE OF SNOW-SQUALLS PUSHING SE FROM 18Z OVER THE CT-VALLEY TO 0Z
ACROSS THE CAPE / ISLANDS. SCT NATURE LEADS TO DIFFICULTY IN TEMPO
OR PREVAILING CONDITIONS IN TAF DUE TO UNCERTAIN IF SQUALLS WILL
MAKE A DIRECT IMPACT TO THE TERMINAL. HAVE PREVAILED -SN IN A
NARROWED TIME-FRAME TO HIGHLIGHT WHEN GREATEST RISK IS EXPECTED.
WITH ANY -SN...EXPECT MIX OF MVFR-IFR CONDITIONS. -SN CONDITIONS
WILL EXIST IN ADVANCE...BUT ONLY EXPECT LOW-END VFR TO MVFR.
WINDS AND WIND GUSTS INCREASED BASED ON UPSTREAM OBS. GUSTS 25 TO
35 KTS OVER THE INTERIOR...35 TO 45 KTS OVER THE WATER.
CONDITIONS IMPROVE VFR BEYOND 0Z. NW-WINDS INITIALLY STRONG WEAKEN
TOWARDS THURSDAY MORNING AND THROUGH THE DAY. MIX OF MVFR-IFR MAY
LINGER OVER THE E-CAPE...PERHAPS ACK...WITH NW-FLOW DUE TO OCEAN-
EFFECT STRATUS / SNOW. NW-GUSTS BY DUSK THURSDAY AROUND 10 TO 15
KTS FOR THE INTERIOR...15 TO 25 KTS ALONG THE SHORES AND WATERS.
KBOS TERMINAL...MODERATE CONFIDENCE IN TAF. -SHSN INITIALLY WITH
ONLY A LOW-END VFR...PERHAPS MVFR. GREATER CONCERN IS WITH SNOW-
SQUALLS EXPECTED AROUND 21-23Z WHICH COULD YIELD MVFR-IFR IMPACTS.
KBDL TERMINAL...MODERATE CONFIDENCE IN TAF. -SHSN INITIALLY WITH
ONLY A LOW-END VFR...PERHAPS MVFR. GREATER CONCERN IS WITH SNOW-
SQUALLS EXPECTED AROUND 18-20Z WHICH COULD YIELD MVFR-IFR IMPACTS.
OUTLOOK...THURSDAY NIGHT INTO SUNDAY...
THURSDAY NIGHT AND FRIDAY...MODERATE TO HIGH CONFIDENCE. MAINLY
VFR...HOWEVER...MVFR CONDITIONS ARE POSSIBLE IN LIGHT SNOW SHOWERS.
GUSTY SOUTHWESTERLY WINDS EXPECTED WITH THE STRONGEST WINDS ACROSS
SOUTHEASTERN MASSACHUSETTS WHERE WINDS COULD GUST AS HIGH AS 50 KTS.
SATURDAY AND SUNDAY...HIGH CONFIDENCE. VFR.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH THURSDAY/...HIGH CONFIDENCE.
1 PM UPDATE...WINDS INCREASED.
THREE CONCERNS:
* OCEAN-EFFECT SNOWS AND REDUCED VISIBILITIES
AS WINDS BACK NW AND WITH PASSAGE OF THE ARCTIC COLD FRONT...
COLDER AIR OVER THE WARMER WATERS WILL YIELD A GREATER LIKELIHOOD
FOR OCEAN-EFFECT SNOW. FOCUS OVER ALL WATERS...BUT GREATEST
IMPACTS ALONG THE NEAR-SHORE FOR LOCATIONS AROUND THE E-CAPE AND
ACK. VISIBILITIES AT TIMES WILL FALL AS LOW AS 1 MILE OR LESS AT
TIMES.
* GALE FORCE WINDS WITH GUSTS POTENTIALLY IN EXCESS OF 40 KTS
GALE FORCE WINDS INCREASING THROUGH THE DAY ESPECIALLY WITH
PASSAGE OF AN ARCTIC COLD FRONT LATE AFTERNOON INTO EVENING. GUSTS
OF 35 TO 45 KTS POSSIBLE DURING THE EVENING TOWARDS MIDNIGHT THEN
TAPERING THEREAFTER. GALE WARNINGS IN EFFECT.
* FREEZING SPRAY
WITH THE GALE FORCE WINDS AND SEAS BUILDING 10 TO 14 FEET WITH AN
AVERAGE OCEAN TEMPERATURE AROUND 42-DEGREES...THE COMBINATION OF
CHOPPY SEAS AND STRONG WINDS WILL YIELD MODERATE FREEZING SPRAY
ESPECIALLY FOR NEAR-SHORE LOCATIONS WHERE THE WATERS ARE SHALLOW
AND COLDER. WORST OF CONDITIONS DEVELOPING BY DUSK AND CONTINUING
INTO MID-MORNING THURSDAY. FREEZING SPRAY ADVISORIES IN EFFECT.
OUTLOOK...THURSDAY NIGHT THROUGH SUNDAY...MODERATE TO HIGH
CONFIDENCE.
THURSDAY NIGHT AND FRIDAY...WINDS AND SEAS INCREASE AHEAD OF A COLD
FRONT THAT WILL MOVE ACROSS THE WATERS FRIDAY. A STRONG LOW LEVEL
JET WILL LEAD TO WINDS GUSTING TO NEAR STORM FORCE ON FRIDAY
MORNING. GALES ARE A LOCK FOR ALL WATERS FOR THIS TIME FRAME WITH A
POTENTIAL FOR STORM WARNINGS.
SATURDAY AND SUNDAY...SMALL CRAFT CONDITIONS ARE LIKELY TO LINGER
SATURDAY MORNING BEFORE HIGH PRESSURE ALLOWS WINDS AND SEAS TO
SUBSIDE.
&&
.CLIMATE...
RECORD LOWS FOR TONIGHT...
BOSTON... -6 SET IN 1878
HARTFORD... -7 SET IN 1968
WORCESTER... -11 SET IN 1968
PROVIDENCE... -4 SET IN 1968
RECORD HIGHS FOR THURSDAY...
BOSTON... 6 SET IN 1968
HARTFORD... 5 SET IN 1968
WORCESTER... -2 SET IN 1968
PROVIDENCE... 7 SET IN 1968
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...WIND CHILL ADVISORY FROM 5 PM THIS AFTERNOON TO 10 AM EST
THURSDAY FOR CTZ002>004.
MA...WIND CHILL ADVISORY FROM 5 PM THIS AFTERNOON TO 10 AM EST
THURSDAY FOR MAZ005>007-010>022-026.
WIND CHILL WARNING FROM 5 PM THIS AFTERNOON TO 10 AM EST
THURSDAY FOR MAZ002>004-008-009.
RI...WIND CHILL ADVISORY FROM 5 PM THIS AFTERNOON TO 10 AM EST
THURSDAY FOR RIZ001>007.
MARINE...FREEZING SPRAY ADVISORY FROM 6 PM THIS EVENING TO 8 AM EST
THURSDAY FOR ANZ231>235-237-250-251-254>256.
GALE WARNING UNTIL 10 AM EST THURSDAY FOR ANZ232>235-237.
GALE WARNING FROM 4 PM THIS AFTERNOON TO 5 AM EST THURSDAY FOR
ANZ230.
GALE WARNING FROM 4 PM THIS AFTERNOON TO 8 AM EST THURSDAY FOR
ANZ231-251.
GALE WARNING UNTIL 8 AM EST THURSDAY FOR ANZ236-250.
GALE WARNING UNTIL 10 AM EST THURSDAY FOR ANZ254>256.
&&
$$
SYNOPSIS...BELK/RLG
NEAR TERM...SIPPRELL
SHORT TERM...BELK
LONG TERM...RLG
AVIATION...BELK/SIPPRELL
MARINE...BELK/RLG/SIPPRELL
CLIMATE...WFO BOX STAFF
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1205 PM EST WED JAN 7 2015
.UPDATE...
AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 438 AM EST WED JAN 7 2015
EXTREMELY COLD AIR WILL CONTINUE TO POUR INTO THE AREA TODAY THROUGH
EARLY THURSDAY AS A STRONG COLD DOME OF HIGH PRESSURE DROPS INTO THE
REGION. AREAS OF BLOWING SNOW CAN BE EXPECTED WITH WIND CHILLS WELL
BELOW ZERO AS WINDS INCREASE EVEN MORE TODAY. AN AREA OF LIGHT SNOW
SHOWERS WILL DROP SOUTH OF THE FORECAST AREA BY LATER THIS MORNING.
MEANWHILE SOME LAKE EFFECT SNOW SHOWERS ACROSS THE NORTHEAST ARE
POSSIBLE BY EARLY IN THE DAY. DRY WEATHER WILL PREVAIL FOR THE END
OF THE WEEK AND MUCH OF THE WEEKEND AS TEMPERATURES BEGIN TO
MODERATE SLIGHTLY...BUT REMAIN BELOW NORMAL THROUGH THE MAJORITY OF
THE FORECAST PERIOD. CHANCES FOR SNOW WILL APPEAR AGAIN AT THE START
OF NEXT WEEK DUE TO AN UPPER LEVEL SYSTEM MOVING THROUGH THE AREA.
&&
.NEAR TERM /LATE MORNING THROUGH THE REST OF TODAY/...
ISSUED AT 923 AM EST WED JAN 7 2015
UPDATE...
EARLY MORNING SNOW SHOWERS HAVE TAPERED OFF OVER SOUTHERN PORTIONS
OF CENTRAL INDIANA. ELSEWHERE...LIGHT LAKE EFFECT SNOW SHOWERS
COULD MAKE THERE WAY INTO THE NORTHEASTERN COUNTIES TODAY...BUT
THE MAIN THREAT WILL BE BLOWING AND DRIFTING SNOW OVER THE
NORTHERN COUNTIES AND THE FRIGID WIND CHILLS OVER ALL OF CENTRAL
INDIANA. STRONG NORTHWEST WINDS WITH SUSTAINED SPEEDS OF 15 TO 20
MPH AND GUSTS UP TO 30 MPH WILL RESULT IN WIND CHILLS FROM -15 TO
-25 DEGREES. CURRENTLY...TEMPS ACROSS THE AREA ARE GENERALLY IN
THE LOW SINGLE DIGITS WITH WIND CHILLS FROM ZERO TO 10 DEGREES
BELOW ZERO. UPDATED GRIDS HAVE BEEN SENT.
PREVIOUS DISCUSSION...
A DISTURBANCE OVER CENTRAL ILLINOIS WHICH NONE OF THE GUIDANCE
PICKED UP ON EXCEPT THE SREF AND HRRR MOVED INTO CENTRAL INDIANA
VERY EARLY THIS MORNING AND STARTED PRODUCING SNOW AT LAF AND
CONTINUES TO DO SO AS IT DROPS SOUTH OVER THE FORECAST
AREA...CURRENTLY STILL SNOWING HERE AT IND BUT SHOULD END AROUND 6
AM. HAD TO UPDATE THE MORNING FORECAST TO ACCOUNT FOR THESE
SCATTERED SNOW SHOWERS. SREF AND HRRR IN DISAGREEMENT ABOUT WHEN THE
SNOW WILL EXIT THE AREA. THE HRRR HAS THE ACTIVITY DISSIPATING OR
SOUTH OF THE AREA BY 12Z...WHILE THE SREF DOES NOT MOVE THE SNOW OUT
OF THE AREA UNTIL 15Z. LEANED CLOSER TO THE SREF SOLUTION BASED ON
LATEST RADAR TRENDS. SO THERE WILL BE SCATTERED CHANCES FOR SNOW
SHOWERS IN THE FORECAST FROM AROUND THE I-70 CORRIDOR AND SOUTHWARD
THROUGH EARLY THIS MORNING. LITTLE TO NO SNOW ACCUMULATION IS
EXPECTED.
ELSEWHERE...LAKE EFFECT SNOW OFF THE SOUTHEASTERN SHORE OF LAKE
MICHIGAN IS SLOWLY MAKING ITS WAY SOUTH TOWARD THE NORTHEAST CORNER
OF THE FORECAST AREA. LEFT IN LOW CHANCES FOR SNOW SHOWERS FROM LATE
THIS MORNING THROUGH THE AFTERNOON HOURS BEFORE THE LAKE EFFECT
MACHINE LETS UP EARLY THIS EVENING.
NOW WE TURN TO THE BIG STORY OF THE DAY AND NEXT 24+ HOURS: THE
DANGEROUSLY COLD WIND CHILLS. EARLY THIS MORNING AFTER COMPLETING
MOST OF THE FORECAST...OPTED TO MAKE ONE ADJUSTMENT TO THE
HEADLINES. REALIZED THAT THE NORTHERN HALF OF THE AREA WHICH WAS
THEN UNDER A WIND CHILL ADVISORY WOULD BE UPGRADED TO A WARNING BY
8AM...A MERE COUPLE OF HOURS. AND SINCE THE WINDS WILL ONLY GROW
STRONGER THROUGH EARLY THIS MORNING AND TEMPERATURES WILL PLUMMET
DECIDED TO DO THE UPGRADE EARLY AND GO WITH A WARNING NOW.
CONDITIONS ARE NOT AT THIS CRITERIA YET BUT WILL BE SHORTLY THIS
MORNING. OTHERWISE LEFT THE REST OF THE HEADLINES INTACT...INCLUDING
THE ADVISORY FOR THE SOUTHERN HALF OF THE CWA...WHICH CAN BE FOUND
UNDER THE PRODUCT ID INDWSWIND. BOTH HEADLINES ARE SET TO EXPIRE AT
10 AM THURSDAY MORNING.
THOSE STRONG NORTHWEST WINDS MENTIONED ABOVE MAY ALSO CAUSE BLOWING
AND DRIFTING OF SNOW...ESPECIALLY FOR LOCATIONS ACROSS THE NORTHERN
HALF OF THE AREA WHERE MORE SNOW WAS RECEIVED YESTERDAY.
AS FOR TEMPERATURES CENTRAL INDIANA IS PROBABLY LOOKING AT THE
WARMEST TEMPS OF THE DAY RIGHT NOW. TEMPERATURE WILL PLUMMET AS
MENTIONED SO THE HIGH TEMPERATURE BETWEEN 12Z TODAY TO 00Z THU WILL
ONLY BE IN THE SINGLE DIGITS...RANGING FROM 0 (NW) TO NEAR 10 ACROSS
THE FAR SOUTH. BLEND OF GUIDANCE SEEMED TO DO A GREAT JOB.
&&
.SHORT TERM /TONIGHT THROUGH FRIDAY NIGHT/...
ISSUED AT 438 AM EST WED JAN 7 2015
TEMPERATURES REMAIN THE MAJOR FOCUS IN THE SHORT TERM WITH A
BITTERLY COLD AIR MASS IN PLACE ACROSS THE AREA. WILL CONTINUE TO
UNDERCUT MODEL NUMBERS...ESPECIALLY OVER THE SNOWPACK...OWING TO
MODEL TENDENCIES TO UNDERESTIMATE THE MAGNITUDE OF ARCTIC OUTBREAKS.
THIS RESULTS IN MIN TEMPS TONIGHT BELOW ZERO ACROSS ALL OF
CENTRAL INDIANA...WITH LOWS AROUND -10 OR BELOW ACROSS THE NORTHERN
HALF. TEMPERATURES WILL BEGIN TO MODERATE SLIGHTLY THURSDAY BUT
REMAIN QUITE COLD. SOME AREAS OF CENTRAL INDIANA...ESPECIALLY ACROSS
THE NORTH...MAY NOT SEE THE 20 DEGREE MARK UNTIL LATE IN THE WEEKEND.
APPARENT TEMPERATURES WILL CONTINUE TO WORSEN TONIGHT AS WINDS STAY
STRONG AND STEADY. CURRENT WIND CHILL WARNING ACROSS THE NORTH AND
ADVISORY ACROSS THE SOUTH HANDLES THIS WELL AND WILL REMAIN
UNCHANGED. EXPIRATION BY 10AM THURSDAY MORNING STILL LOOKS GOOD THIS
FORECAST ISSUANCE.
BY THURSDAY NIGHT A WEAK LITTLE SYSTEM OVER THE GREAT LAKES MAY
PRODUCE CHANCES FOR SCATTERED FLURRIES ACROSS THE NORTH. NO
ACCUMULATING SNOW IS EXPECTED DURING THIS TIME. TEMPERATURES BEGIN
TO SLOWLY MODERATE INTO FRIDAY HOWEVER STILL VERY COLD AND BELOW
NORMAL WITH HIGHS ONLY IN THE TEENS.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
ISSUED AT 438 AM EST WED JAN 7 2015
HIGH PRESSURE OVER THE AREA TO BEGIN THE LONG TERM. THE HIGH MOVES
OFF TO THE EAST ALLOWING WARMER AIR TO MAKE ITS WAY INTO CENTRAL
INDIANA. ANOTHER SURFACE HIGH ATTEMPTS TO BUILD IN FROM THE
NORTHWEST...BUT MODELS DIFFER ON HOW QUICKLY THIS OCCURS. GFS SHOWS
A FAIRLY QUICK TRANSITION FROM ONE HIGH TO THE NEXT BUT THE ECMWF
DEVELOPS A WEAK FRONTAL ZONE BETWEEN THE HIGHS AND BRINGS
PRECIPITATION INTO THE AREA FROM SUNDAY NIGHT ON. GIVEN THE
UNCERTAINTY KEPT THE SLIGHT TO LOW CHANCE POPS FROM THE
INITIALIZATION FROM SUNDAY NIGHT ON...BUT SHOULD NOTE THAT COULD
JUST AS EASILY SEE DRY WEATHER AS WET WEATHER FOR THE BEGINNING OF
THE WORK WEEK.
&&
.AVIATION /DISCUSSION FOR 071800Z TAF ISSUANCE/...
ISSUED AT 1205 PM EST WED JAN 7 2015
VFR THROUGH THE PERIOD. ALTHOUGH GUSTY WINDS COULD CAUSE SOME
BLOWING SNOW AT KIND AND KLAF TAF SITES.
COLD ARCTIC HIGH PRESSURE CENTERED OVER THE NORTHERN AND CENTRAL
PLAINS WILL MOVE TO THE OHIO VALLEY BY 12Z THURSDAY AND TO THE
CAROLINAS BY THIS TIME THURSDAY.
MODEL SOUNDINGS INDICATE MAYBE A FEW CU THIS AFTERNOON AND THEN
MOSTLY CLEAR TONIGHT. MID/HIGH CLOUDS WILL INCREASE ACROSS THE
REGION THURSDAY AS ANOTHER COLD FRONT MOVES INTO THE UPPER MIDWEST.
EXPECT MAINLY SCATTERED MID CLOUDS THURSDAY MORNING AND BROKEN MID
CLOUDS AFTER 18Z THURSDAY.
NORTHWEST WINDS OF 15 TO 18 KNOTS AND GUSTS NEAR OR SLIGHTLY ABOVE
25 KNOTS WILL BE THE RULE THIS AFTERNOON. WINDS WILL BECOME WEST AT
5 TO 10 KNOTS TONIGHT AS PRESSURE GRADIENT WEAKENS. ON THURSDAY
SOUTHWEST WINDS OF 12 TO 15 KNOTS WILL BE THE RULE.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
WIND CHILL ADVISORY UNTIL 10 AM EST THURSDAY FOR INZ051>057-
060>065-067>072.
WIND CHILL WARNING UNTIL 10 AM EST THURSDAY FOR INZ021-028>031-
035>049.
&&
$$
SYNOPSIS...SMF
NEAR TERM...SMF/TDUD
SHORT TERM...SMF
LONG TERM....CP
AVIATION...JH
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AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
328 PM CST WED JAN 7 2015
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 326 PM CST WED JAN 7 2015
MAIN CONCERN IN THE SHORT TERM WAS TIMING A CLIPPER INTO THE AREA
TONIGHT...FOLLOWED BY BLOWING SNOW AND BLIZZARD CONCERNS THU
AFTERNOON INTO THU NIGHT.
FOR THE SNOW...MODELS ARE ALL CONSISTENT WITH A WNW-ESE ORIENTED
BAND OF SNOW WITH TOTAL QPF OF AROUND 0.15 FALLING. WHERE THEY STILL
DISAGREE IS HOW FAR NORTH/SOUTH THAT BAND WILL BE. COMPARING
RUN-TOTAL QPFS THRU 12Z THU FROM VARIOUS MODELS TO WHAT THE RAP HAS
THROUGH THAT TIME /WHICH IS ESSENTIALLY THE END OF IT FORECAST
PERIOD/...IT INDICATES THE ECMWF IS RUNNING A LITTLE SLOW AND
NORTH...WHILE THE GEM IS FAST AND SOUTH. IN BETWEEN...AND MATCHING
UP WELL WITH WHAT THE RAP HAS THRU 12Z THU WERE THE SREF AND
NAM...SO BLENDED THE QPF FORECAST THAT DIRECTION...RESULTING IN
0.1-0.15" MELTED PRECIP BASICALLY ALONG AND NORTH OF I-94...WHICH
RESULTED IN A SLIGHT SOUTHWESTWARD SHIFT FROM THE PREVIOUS FORECAST.
UNLIKE SUNDAY NIGHTS SNOW WHEN ALMOST OUR ENTIRE PROFILE WAS COLDER
THAN -20C...RESULTING IN SNOW RATION CLOSER TO 10:1...PROFILES WITH
THIS SNOW ARE WARMER...WITH DEEPER SECTIONS IN THE ATMO GETTING INTO
THE FAVORED DGZ. AS A RESULT...EXPECT SNOW RATIOS UP MORE IN THE
16-19:1 RANGE...WHICH TRANSLATES TO A GOOD 1-3...MAYBE 4 INCHES
WITHIN THE HEAVIEST QPF SWATH. AMOUNTS WILL TAIL OFF PRETTY QUICK SW
OF I-94...BUT STILL LOOKS LIKE MOST OF THE AREA SHOULD SEE A LITTLE
BIT OF SNOW...WHICH WILL BE IMPORTANT FOR THU AFTN/NIGHT FOR WHEN
THE STRONG NW WINDS ARRIVE.
AS FOR THE WINDS...NOT MUCH CHANGED WITH THE GOING FORECAST. WE
STILL LOOK TO GET INTO STRONG CAA...WHICH WILL RESULT IN STEEP LAPSE
RATES AND BOUNDARY LAYER MIXING TO ABOVE 900 MB. NAM SOUNDINGS STILL
SHOW A SOLID 8-10 HOURS OUT AT RWF/FRM WHERE MIX DOWN WINDS ARE 35
KTS IN THE MID CHANNEL...WITH 45 KTS AT THE TOP OF THE
CHANNEL...WHICH SHOULD EASILY TRANSLATE INTO FREQUENT GUSTS OVER 40
MPH. FOR BLOWING SNOW/BLIZZARD ISSUES...THE BIG QUESTION WHERE AND
HOW MUCH SNOW FALLS. FOR THE AREA WITH THE BLIZZARD WATCH...A QUICK
TOUR OF ROADSIDE CAMERAS ACROSS THAT AREA SHOWED A SNOW PACK THAT
HAS BEEN WORKED OVER PRETTY GOOD IN THE LAST 24 HOURS...AND WILL
NEED SOME FRESH SNOW TO GET SIGNIFICANT BLOWING SNOW ISSUES GOING.
UNFORTUNATELY...THE BLIZZARD WATCH AREA ALSO LOOKS TO BE THE PART OF
THE MPX CWA THAT SEES THE LEAST AMOUNT OF SNOW...SO THE QUESTION
IS...IS A HALF INCH OF FRESH SNOW ENOUGH TO CREATE BLIZZARD
CONDITIONS. GIVEN THE UNCERTAINTIES THAT ARE STILL IN PLACE...LEFT
THE BLIZZARD WATCH IN PLACE...BUT RIGHT NOW...WOULD PLACE THE ODDS
AT NEEDING AN WINTER WEATHER ADVY FOR BLOWING SNOW BEING HIGHER THAN
SEEING IT UPGRADED TO A BLIZZARD WARNING. WITH THAT SAID...THE GEM
SHOWS ALMOST OUR ENTIRE CWA GETTING 2 INCHES OF SNOW...AND IF THAT
WERE TO HAPPEN...THEN A BLIZZARD WARNING WOULD LIKELY BE NEEDED FOR
WHERE THE WATCH CURRENTLY IS.
OUTSIDE OF THE BLIZZARD WATCH...WE WILL LIKELY NEED AN ADVY FOR
BLOWING SNOW AS WELL...AS ALTHOUGH THE MEAGER SNOW CURRENTLY ON THE
GROUND IN CENTRAL MN IS NOT GOING TO CREATE BLSN ISSUES...A FRESH
INCH OF POWDER WILL LIKELY CREATE HAZARDOUS CONDITIONS IN BLOWING
SNOW...THOUGH THE LACK OF EXISTING SNOW COVER SHOULD KEEP
VISIBILITIES IN CHECK. HOWEVER...DECIDED TO HOLD OFF ON A ISSUING AN
ADVY AT THIS TIME UNTIL WE GET A BETTER HANDEL ON EXACTLY WHERE AND
HOW MUCH SNOW WE WILL SEE ACROSS MN. FOR ERN MN AND WRN WI...AN ADVY
SHOULD NOT BE NEEDED AS ONE...THE EXPECTED AMOUNTS DO NOT GET TO OUR
ADVY CRITERIA...WHILE LIGHTER WINDS WILL LEAD TO FEWER ISSUES WITH
BLOWING SNOW.
OF COURSE WE CAN NOT FORGET THAT WITH TEMPERATURES HOVERING AROUND
ZERO...WE ARE STILL SEEING WIND CHILL VALUES BETWEEN -20F AND -30F.
HOWEVER...LOWS TONIGHT LOOK TO COME BY 3Z IN WC MN AND 6Z IN WC WI
AS THE COMBINATION OF WINDS TURNING TO THE SW AND BRINGING IN WAA
ALONG WITH CLOUDS INCREASING FROM THE NW WILL RESULT IN STEADY OR
RISING TEMPERATURES AFTER 3Z/6Z. THESE RISING TEMPERATURES EXPLAIN
WHY WC AND CENTRAL MN WERE LEFT OUT OF THE WIND CHILL ADVY AS WIND
CHILL VALUES THERE WILL REMAIN BETWEEN 15 AND 25 BELOW...AS THIS
WILL BE THE "WARMEST" PART OF THE MPX CWA FOR ACTUAL AIR
TEMPERATURES THROUGH THE NIGHT.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 326 PM CST WED JAN 7 2015
FRIDAY/S THERMAL PROFILE IS COMPARABLE TO TODAY/S 92H/85H TEMPS...OR
A FEW DEGREES WARMER. THIS BASICALLY TRANSLATES TO MORNING LOWS
SIMILAR TO THIS MORNING...ESPECIALLY CONSIDERING THE ADDED NEW
SNOWFALL EXPECTED OVER THE NEXT 24 HRS. WIND SPDS WILL ALSO BE
SIMILAR WITH 10 TO 20 MPH...WITH OCCASIONAL GUSTS OF 20 TO 30
MPH...ESPECIALLY DURING THE MORNING. BASED ON CURRENT FORECAST SFC
TEMPS/WIND SPD...WIND CHILL VALUES WILL BE CLOSE AGAIN TO WARNING
CRITERIA WHICH IS -35F OR LOWER FRIDAY MORNING. HOWEVER...IT MAY
BE ONE OF THOSE THAT COULD BE A HIGH END WIND CHILL ADVISORY BASED
ON THIS MORNING VALUES.
THE OVERALL PATTERN REMAINS THE SAME IN THE EXTENDED PERIOD WITH A
GRADUAL BREAK DOWN ON THE MEAN TROUGH IN THE EASTERN PART OF NORTH
AMERICA...WITH THE CENTER OF THE ARCTIC LOW SHIFTING TO THE NE
ACROSS NE CANADA. THIS SHOULD LEAD TO A MORE PROGRESSIVE AND
POSSIBLY ZONAL FLOW BY LATE NEXT WEEK IN OUR REGION. NO MAJOR
SYSTEMS WILL MOVE ACROSS THE AREA...LEADING TO A DRY FORECAST.
SOME OF THE STANDARDIZED ANOMALY OF 85H/50H HEIGHTS/TEMPS IN THE
EXTENDED PERIOD ALSO INDICATE A GRADUAL WARMING TREND. CURRENT
FORECAST TEMPS SLOWLY RISE FROM NEAR ZERO ON FRIDAY...TO THE TEENS
AND 20S BY THE MIDDLE OF NEXT WEEK. BASED ON THE CURRENT TREND OF
THE EC/GFS MEAN 85H TEMPS AND THICKNESS VALUES OF THE 100-50H...DOES
SHOW NEAR FREEZING SFC TEMPS OR ABV FREEZING BY LATE NEXT WEEK...AND
INTO THE FOLLOWING WEEKEND. THIS AGAIN IS BASED ON THE SLOW
TRANSITION OF THE MEAN TROUGH...TO A MORE QUASI-ZONAL FLOW FOR OUR
REGION. ONE ITEM TO NOTE IS THE STRONG DEVELOPMENT OF THE MEAN
TROUGH IN THE GULF OF ALASKA. THIS WILL BE A MAJOR FACTOR OF THE
MEAN RIDGE IN THE WEST TO SLOWLY BREAK DOWN.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1152 AM CST WED JAN 7 2015
MAIN CONCERN IN TAFS IS TIMING SNOW IN THU MORNING. NAM/GFS PRETTY
SIMILAR WITH THEIR HANDLING OF THIS CLIPPER...SO STUCK CLOSE TO
THEIR TIMING. FOR THE TAFS...FAVORED THE SLIGHTLY FASTER TIMING OF
THE GFS...THOUGH AT THIS POINT...EXPECT SNOW TO START WITHIN AN
HOUR OR TWO AT MOST OF WHAT THE TAFS HAVE. FOR THE MOST
PART...EXPECT 1-2SM VIS WITH THE SNOW...BUT DO THINK ALL BUT RWF
WILL SEE A 2-3 HOUR PERIOD WHERE VSBYS WILL GET DOWN INTO THE
1/2SM-3/4SM RANGE...HENCE THE TEMPO GROUPS SEEN. THROUGH
TONIGHT...WE SHOULD JUST BE ABLE TO REFINE THE TIMING SEEN NOW.
KMSP...CONFIDENCE IS HIGH IN ANOTHER COUPLE INCH SNOW EVENT
IMPACTING MSP...WITH ITS TIMING CENTERED AROUND 18Z. WINDOW FOR
SNOW ONSET LOOKS TO BE BETWEEN 1330Z AND 15Z. WILL LIKELY HAVE A
2-3 HOUR WINDOW WHERE RATES AT TIMES GET UP INTO THE 3/4 INCH PER
HOUR RANGE. GIVEN COLD CONDITIONS...THIS WILL AGAIN BE A LOWER
DENSITY AND DRY SNOW.
/OUTLOOK FOR KMSP/
FRI...VFR. WINDS WNW 15G25 KTS.
SAT...VFR. WINDS SW 10 KTS.
SUN...VFR. WINDS NW 5-10 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...WIND CHILL ADVISORY UNTIL 6 AM CST THURSDAY FOR MNZ053-060>070-
073>078-082>085-091>093.
BLIZZARD WATCH FROM THURSDAY AFTERNOON THROUGH LATE THURSDAY
NIGHT FOR MNZ064-065-067-073>076-082>085-091>093.
WI...WIND CHILL ADVISORY UNTIL 6 AM CST THURSDAY FOR WIZ014>016-
023>028.
&&
$$
SHORT TERM...MPG
LONG TERM...JLT
AVIATION...MPG