Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 11/15/14
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
854 AM PST THU NOV 13 2014
.SYNOPSIS...OUTSIDE OF A FEW SHOWERS INTO THE AFTERNOON HOURS,
LOOK FOR COOL AND DRY CONDITIONS TODAY. HIGH PRESSURE WILL THEN
REBUILD WITH A RETURN TO DRY AND SEASONABLE WEATHER THROUGH THE
UPCOMING WEEKEND. RAIN MAY RETURN NEXT WEEK BUT PROBABLY NOT UNTIL
MIDWEEK OR BEYOND.
&&
.DISCUSSION...AS OF 8:50 AM PST THURSDAY...RAIN HAS ENDED ACROSS
MOST OF OUR AREA, ALTHOUGH KMUX IS STILL SHOWING A FEW ECHOS OVER
SOUTHEASTERN PORTIONS OF THE CWA. RAINFALL TOTALS HAVE BEEN
GENERALLY UNDER 1/3" FOR URBAN SPOTS WITH A FEW HIGHER ELEVATION
LOCATIONS ABOVE HALF AN INCH. ONCE STATION ON MOUNT TAM ENDED UP
WITH AROUND 3/4". MINOR FORECAST UPDATE WAS DONE TO REFLECT THE
RAINFALL ENDED THIS MORNING.
MAIN FORECAST CONCERN WILL BE FOR POSSIBLE RAINFALL LATE SATURDAY
INTO SUNDAY PLUS NEXT WORK WEEK. STILL WAITING ON THE ECMWF TO
COME IN BEFORE DECIDING TO MAKE ANY SUBSTANTIAL CHANGES TO THE
FORECAST.
.PREVIOUS DISCUSSION...RAIN EVENT SEEMS TO BE VERIFYING ABOUT AS
ADVERTISED WITH QUARTER INCH RAIN TOTALS ON AVERAGE. THERE HAVE
BEEN A FEW SITES AROUND HALF INCH IN THE NORTH BAY AND LESSER
AMOUNTS FROM MONTEREY SOUTHWARD...BUT IT SEEMS LIKE MOST AREAS
RECEIVED FAIRLY UNIFORM LIGHT RAIN AMOUNTS. SCATTERED SHOWERS AND
AREAS OF FOG WILL IMPACT THE EARLY MORNING COMMUTE WITH SOME WET
ROADWAYS. IN GENERAL CONDITIONS WILL RAPIDLY IMPROVE BY 17-18Z
WITH MOST SHOWER ACTIVITY WINDING DOWN EXCEPT PERHAPS SOME OF THE
INLAND HILLS OF SANTA CLARA AND SAN BENITO COUNTY.
WILL HAVE TO MONITOR FOR POSSIBLE FOG FORMATION TONIGHT GIVEN
TODAY`S LIGHT RAIN AND THEN SOME HIGH PRESSURE QUICKLY BUILDING
OVER THE REGION. DRY WEATHER WILL RETURN FOR FRIDAY WITH
SEASONABLE TEMPERATURES IN THE 60S. RIGHT NOW THERE IS HIGH
CONFIDENCE FOR DRY WEATHER AT LEAST THROUGH SATURDAY IN TERMS OF
WEEKEND PLANNING WITH AFTERNOON HIGHS IN THE UPPER 60S AND LOWER 70S.
THE LONG RANGE FORECAST REMAINS SOMEWHAT MUDDLED. THE DRIVING
FORCE SEEMS TO BE THE ARCTIC AIR THAT IS BECOMING ENTRENCHED OVER
THE EASTERN HALF OF THE COUNTRY. THEN LATE SATURDAY INTO SUNDAY A
CHUNK OF COLD AIR WANTS TO DROP INTO THE NORTHERN ROCKIES AND TRY
AND EXTEND AS FAR WEST AS EASTERN OREGON AND WESTERN NEVADA. SOME
OF THE MODELS WANT TO BRING THIS SYSTEM DOWN INTO CALIFORNIA BUT
THE MOST OBJECTIVE GUIDANCE SUGGESTS IT SHOULD STAY EAST OF THE
SIERRA. UPSHOT IS TO KEEP THE BAY AREA FORECAST DRY ON SUNDAY FOR
THE TIME BEING.
THE LONG RANGE FORECAST REMAINS PROBLEMATIC AS WELL WITH LOTS OF
JET STREAM ENERGY OVER THE PACIFIC...THE RIDGE OVER ALASKA AND THE
COLD TROUGH OVER THE EASTERN US. WERE SEEING POOR MODEL RUN TO RUN
CONSISTENCY. LATEST SOLUTIONS HAVE THE GEM BEING PRETTY WET AND
INDICATING POTENTIAL FOR MULTIPLE STORMS NEXT WEEK WHILE THE GFS
HAS GONE DRY UNTIL LATE NEXT WEEK. INTERNAL COMPUTER ISSUES DIDN`T
ALLOW ECMWF ANALYSIS TONIGHT AND THE LONG FORECAST WAS BLENDED
WITH SURROUNDING WFOS. IN TERMS OF RAINFALL LOOKS LIKE PATIENCE
WILL BE NEEDED.
&&
.AVIATION...AS OF 4:30 AM PST THURSDAY...STORM SYSTEM JUST
OFFSHORE OF NORCAL COASTLINE SPREADING -RA AND MVFR CIGS/VISBY
ACROSS TAF SITES THIS MORNING. HRRR SUGGESTS BULK OF WIDESPREAD
PRECIP DWINDLES AFTER 14Z WITH -SHRA/VCSH LIKELY THROUGH BAY AREA
UNTIL 19Z THU AND MONTEREY BAY AIRPORTS THROUGH 22Z THU. WINDS VEER
WITH FRONTAL PASSAGE TOWARDS THE WEST BETWEEN 18Z AND 19Z THU AT
KSFO AND KOAK. MEDIUM CONFIDENCE ON TIMING OF WIND SHIFT/RAIN
TAPER.
VICINITY OF KSFO...PREDOMINATELY MVFR CIGS THROUGH THURSDAY
MORNING WITH SLIGHT PROBABILITY OF IFR CIGS. PRECIPITATION TAPERS
OFF AFTER 14Z THU... WITH LIGHTER RAIN SHOWERS IN VICINITY THROUGH
19Z THU. WINDS VEER FROM SE TO SW 17-18Z THU.
KSFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...MVFR CIGS. PRECIPITATION TAPERS OFF
AFTER 16Z WITH LIGHTER RAIN SHOWERS IN VICINITY THROUGH 22Z THU.
&&
.MARINE...AS OF 04:05 AM PST THURSDAY...NORTHWEST WINDS HAVE
DEVELOPED OVER THE COASTAL WATERS IN THE WAKE OF FRONTAL PASSAGE
AND WILL PERSIST INTO THE WEEKEND. NW WINDS GRADUALLY DECLINE INTO
THE WEEKEND EXCEPT ALONG THE BIG SUR COASTLINE. WEST TO NORTHWEST
DOMINATE SWELL WITH GRADUALLY SHORTENING PERIODS ARE EXPECTED
THROUGH THE FORECAST PERIOD.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...NONE.
$$
PUBLIC FORECAST: BELL/RWW
AVIATION/MARINE: DRP
VISIT US AT WEATHER.GOV/SANFRANCISCO
FOLLOW US ON FACEBOOK, TWITTER, AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSBAYAREA
WWW.TWITTER.COM/NWSBAYAREA
WWW.YOUTUBE.COM/NWSBAYAREA
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
433 AM PST THU NOV 13 2014
.SYNOPSIS...SCATTERED SHOWERS WILL CONTINUE EARLY THIS MORNING ACROSS
THE BAY AREA BUT END BY MID-MORNING OR LUNCHTIME. HIGH PRESSURE
WILL THEN REBUILD WITH A RETURN TO DRY AND SEASONABLE WEATHER
THROUGH THE UPCOMING WEEKEND. RAIN MAY RETURN NEXT WEEK BUT
PROBABLY NOT UNTIL MIDWEEK OR BEYOND.
&&
.DISCUSSION...AS OF 3:43 AM PST THURSDAY...RAIN EVENT SEEMS TO BE
VERIFYING ABOUT AS ADVERTISED WITH QUARTER INCH RAIN TOTALS ON
AVERAGE. THERE HAVE BEEN A FEW SITES AROUND HALF INCH IN THE NORTH
BAY AND LESSER AMOUNTS FROM MONTEREY SOUTHWARD...BUT IT SEEMS LIKE
MOST AREAS RECEIVED FAIRLY UNIFORM LIGHT RAIN AMOUNTS. SCATTERED
SHOWERS AND AREAS OF FOG WILL IMPACT THE EARLY MORNING COMMUTE
WITH SOME WET ROADWAYS. IN GENERAL CONDITIONS WILL RAPIDLY IMPROVE
BY 17-18Z WITH MOST SHOWER ACTIVITY WINDING DOWN EXCEPT PERHAPS
SOME OF THE INLAND HILLS OF SANTA CLARA AND SAN BENITO COUNTY.
WILL HAVE TO MONITOR FOR POSSIBLE FOG FORMATION TONIGHT GIVEN
TODAYS LIGHT RAIN AND THEN SOME HIGH PRESSURE QUICKLY BUILDING
OVER THE REGION. DRY WEATHER WILL RETURN FOR FRIDAY WITH
SEASONABLE TEMPERATURES IN THE 60S. RIGHT NOW THERE IS HIGH
CONFIDENCE FOR DRY WEATHER AT LEAST THROUGH SATURDAY IN TERMS OF
WEEKEND PLANNING WITH AFTERNOON HIGHS IN THE UPPER 60S AND LOWER 70S.
THE LONG RANGE FORECAST REMAINS SOMEWHAT MUDDLED. THE DRIVING
FORCE SEEMS TO BE THE ARCTIC AIR THAT IS BECOMING ENTRENCHED OVER
THE EASTERN HALF OF THE COUNTRY. THEN LATE SATURDAY INTO SUNDAY A
CHUNK OF COLD AIR WANTS TO DROP INTO THE NORTHERN ROCKIES AND TRY
AND EXTEND AS FAR WEST AS EASTERN OREGON AND WESTERN NEVADA. SOME
OF THE MODELS WANT TO BRING THIS SYSTEM DOWN INTO CALIFORNIA BUT
THE MOST OBJECTIVE GUIDANCE SUGGESTS IT SHOULD STAY EAST OF THE
SIERRA. UPSHOT IS TO KEEP THE BAY AREA FORECAST DRY ON SUNDAY FOR
THE TIME BEING.
THE LONG RANGE FORECAST REMAINS PROBLEMATIC AS WELL WITH LOTS OF
JET STREAM ENERGY OVER THE PACIFIC...THE RIDGE OVER ALASKA AND THE
COLD TROUGH OVER THE EASTERN US. WERE SEEING POOR MODEL RUN TO RUN
CONSISTENCY. LATEST SOLUTIONS HAVE THE GEM BEING PRETTY WET AND
INDICATING POTENTIAL FOR MULTIPLE STORMS NEXT WEEK WHILE THE GFS
HAS GONE DRY UNTIL LATE NEXT WEEK. INTERNAL COMPUTER ISSUES DIDNT
ALLOW ECMWF ANALYSIS TONIGHT AND THE LONG FORECAST WAS BLENDED
WITH SURROUNDING WFOS. IN TERMS OF RAINFALL LOOKS LIKE PATIENCE
WILL BE NEEDED.
&&
.AVIATION...AS OF 4:30 AM PST THURSDAY...STORM SYSTEM JUST
OFFSHORE OF NORCAL COASTLINE SPREADING -RA AND MVFR CIGS/VISBY
ACROSS TAF SITES THIS MORNING. HRRR SUGGESTS BULK OF WIDESPREAD
PRECIP DWINDLES AFTER 14Z WITH -SHRA/VCSH LIKELY THROUGH BAY AREA
UNTIL 19Z THU AND MONTEREY BAY AIRPORTS THROUGH 22Z THU. WINDS VEER
WITH FRONTAL PASSAGE TOWARDS THE WEST BETWEEN 18Z AND 19Z THU AT
KSFO AND KOAK. MEDIUM CONFIDENCE ON TIMING OF WIND SHIFT/RAIN
TAPER.
VICINITY OF KSFO...PREDOMINATELY MVFR CIGS THROUGH THURSDAY
MORNING WITH SLIGHT PROBABILITY OF IFR CIGS. PRECIPITATION TAPERS
OFF AFTER 14Z THU... WITH LIGHTER RAIN SHOWERS IN VICINITY THROUGH
19Z THU. WINDS VEER FROM SE TO SW 17-18Z THU.
KSFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...MVFR CIGS. PRECIPITATION TAPERS OFF
AFTER 16Z WITH LIGHTER RAIN SHOWERS IN VICINITY THROUGH 22Z THU.
&&
.MARINE...AS OF 04:05 AM PST THURSDAY...NORTHWEST WINDS HAVE
DEVELOPED OVER THE COASTAL WATERS IN THE WAKE OF FRONTAL PASSAGE
AND WILL PERSIST INTO THE WEEKEND. NW WINDS GRADUALLY DECLINE INTO
THE WEEKEND EXCEPT ALONG THE BIG SUR COASTLINE. WEST TO NORTHWEST
DOMINATE SWELL WITH GRADUALLY SHORTENING PERIODS ARE EXPECTED
THROUGH THE FORECAST PERIOD.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...NONE.
$$
PUBLIC FORECAST: RWW
AVIATION/MARINE: DRP
VISIT US AT WEATHER.GOV/SANFRANCISCO
FOLLOW US ON FACEBOOK, TWITTER, AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSBAYAREA
WWW.TWITTER.COM/NWSBAYAREA
WWW.YOUTUBE.COM/NWSBAYAREA
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
928 AM EST THU NOV 13 2014
.SYNOPSIS...
A QUICK MOVING COASTAL LOW FORMS ALONG A COLD FRONT OFFSHORE
TONIGHT AND MOVES TO THE EAST OF THE REGION EARLY FRIDAY. HIGH
PRESSURE FOLLOWS FOR A MAJORITY OF THE WEEKEND BEFORE ANOTHER COLD
FRONT MOVES THROUGH MONDAY MORNING. LOW PRESSURE SYSTEM, FORMING
ALONG THE GULF COAST, MOVES ALONG THE FRONT CLOSE TO OUR REGION ON
MONDAY INTO TUESDAY. HIGH PRESSURE MOVES BACK IN BEHIND THIS
DEPARTING SYSTEM LATE ON TUESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MID AND HIGH LEVEL CLOUDS WERE SPREADING OVER OUR REGION FROM THE
WEST AND SOUTHWEST THIS MORNING. THE SKY IS EXPECTED TO BECOME
OVERCAST FOR THIS AFTERNOON.
TEMPERATURES WERE MAINLY IN THE UPPER 30S AND LOWER 40S AT 900
AM. THE INCREASING CLOUD COVER WILL PREVENT TEMPERATURES FROM
RISING ABOVE THE 40S DURING THE AFTERNOON HOURS. A NORTHERLY WIND
AT 5 TO 10 MPH IS EXPECTED TO BACK TOWARD THE NORTHWEST AS THE DAY
PROGRESSES.
THE HRRR CONTINUES TO SUPPORT THE IDEA OF LIGHT RAIN SPREADING
INTO THE WESTERN AND SOUTHERN PARTS OF OUR FORECAST AREA LATE THIS
AFTERNOON.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM FRIDAY/...
WIDESPREAD LIGHT PCPN ANTICIPATED AS A 140 MB HFC DEVELOPS OVER E
PA BY FRIDAY MORNING. VERY NICE FGEN THIS EVENING AND BOTH THE 00Z
AND 06Z/13 OPERATIONAL GFS HAVE ABOUT 17MBAR/SEC SNOW GROWTH
MODELED OVER NE NJ BY 06Z FRI (550MB). THE NAM IS LESS ROBUST.
NOTICING ALSO DECENT SNOW GROWTH ELSEWHERE I95 REGION NEAR 04-06Z
DESPITE DRYING IN THE LOW LVLS AS NW WINDS INCREASE. COULD SEE
BRIEF 1 MI LIGHT SNOW ALL ALONG I95 CORRIDOR FOR AN HOUR SO IN THE
10PM TO 2 AM TIME FRAME.
LOOKING AT MAX WBZ UNDER 2C IN THE 0-6KM LAYER AND BL LESS THAN
0C IN LOWEST 750 FT...WE SHOULD SEE RAIN CHANGE TO SNOW NW OF I95
THIS EVENING AND THE QUESTION HOW QUICKLY DOES IT START
STICKING... PROBABLY A MATTER OF ELEVATION AND TO SOME DEGREE
INTENSITY. ITS CERTAINLY APPEARING TO BE SPS MATERIAL BUT NOT AN
ADVY NW OF I95.
I95 ITSELF...COULD END UP WITH A SKIFF OF SNOW ON THE GRASS IN
SOME PLACES AS RAIN ENDS AS SNOW.
PRIMARY PCPN EVENT IS 5 PM THIS AFTERNOON TO 3 AM FRIDAY.
CLEARING TOWARD DAWN FRIDAY IN E PA AS WELL AS STIFFENING CAA
SHOULD PERMIT SOME ICY SPOTS TO LINGER ON UNTREATED SFC TOMORROW
MORNING FROM NW NJ THRU E PA (MAINLY WEST OF THE I95 CORRIDOR).
THE 330 AND 630 AM FORECAST INCLUDING SNOW MAP I THINK IS
CONSERVATIVE AND I COULD SEE ANYWHERE FROM .1 TO .5 ADDITIONAL TO
THE TOTALS POSTED EARLY TODAY. I JUST DIDNT WANT TO FORCE THE
TOOLS ANY FURTHER. ITS POSSIBLE I DID NOT COOL THE SFC TEMPS FAST
ENOUGH THIS EVENING IN E PA AND NW NJ WHICH WOULD LEAD TO A
SLIGHTLY HIGHER SNOW TOTAL.
POPS WERE ADJUSTED UPWARD BY 20 PCT IN DELAWARE FOR THIS 630 AM
ESTF.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
PERSISTENT MID-LEVEL TROUGHING OVER THE EASTERN HALF OF THE CONUS
THROUGH THE LONG TERM. THOUGH THE TROUGH WILL RELOAD SEVERAL TIMES
OVER THE NEXT 7 DAYS BRINGING WITH IT BOUTS OF UNSETTLED WEATHER,
TEMPERATURES WILL AVERAGE WELL BELOW NORMAL.
FRIDAY - SATURDAY...COLD FRONT WILL BE OFFSHORE WITH THE LAST OF
THE LINGERING MOISTURE ASSOCIATED WITH THE QUICK COASTAL LOW MOVES
AS IT MOVES INTO NEW ENGLAND. A FEW LAKE EFFECT STREAMERS MAY MAKE
IT INTO OUR EXTREME NORTHERN ZONES, BUT WITH A FRESH AND DRY
AIR MASS IN PLACE SHOULD BE MORE IN THE WAY OF FLURRIES. GUSTY
NORTHWEST WINDS WILL HELP TO KEEP WIND CHILL VALUES IN THE MID-
30S. SATURDAY THE SURFACE FLOW BECOMES MORE WESTERLY AS THE DRYING
TREND CONTINUES WITH WEAK RIDGING MOVING IN ALOFT. TEMPERATURES
EACH DAY WILL AVERAGE IN THE LOW-40S.
SUNDAY...SURFACE HIGH PRESSURE AND THE WEAK RIDGING BREAK DOWN
AND MOVE OFFSHORE. LIGHT SOUTHERLY FLOW COMMENCES, THOUGH NOT
EXPECTING A GREAT DEAL OF AIR MASS MODIFICATION WITH TEMPERATURES
STILL IN THE 40S...DEWPOINTS INCREASE. THIS IS ALL AHEAD OF THE
NEXT COLD FRONT PROGGED TO PUSH THROUGH LATE ON SUNDAY NIGHT INTO
MONDAY MORNING. WE LOOK TO REMAIN DRY SUNDAY BEFORE INCREASING
THETA-E ADVECTION KICKS IN WITH STRONGER LOW-LEVEL SOUTHERLY FLOW
AND A PASSING MID-LEVEL SHORTWAVE LATE SUNDAY NIGHT. THERMALLY WE
LOOK WARM ENOUGH FOR A MOSTLY OVER-RUNNING RAIN FROM THE LEHIGH
VALLEY SOUTHWARD WITH A COLD BOUNDARY LAYER ACROSS THE NORTH FOR
MOSTLY SNOW.
MONDAY - TUESDAY...GUIDANCE CONTINUES TO INDICATE THAT THE
NORTHERN STREAM ENERGY WILL BE THE DOMINATE FEATURE AS THE MID-
LEVEL TROUGH RELOADS OVER THE GREAT LAKES AND AS THE GULF COAST
LOW MOVES BY OUR REGION. PHASING STILL DOES NOT LOOK TO OCCUR
THOUGH A JOG TOWARDS THE WEST-NORTHWEST HAS BEEN NOTED OVER THE
PAST DAY OF RUNS WITH THE GFS...EC MOVED A LITTLE FURTHER EAST.
THIS SETUP CONTINUES TO SHOW AN ABOVE 0C LOW-LEVEL PROFILE AS WARM
AIR ADVECTS INTO THE REGION FROM THE SOUTH....COULD BE COLD ENOUGH
AT THE START ACROSS THE NORTH FOR SNOW CHANGING TO RAIN DURING THE
EVENT. ENSEMBLES SHOW A DECENT AMOUNT OF SPREAD STILL EXISTS SO WE
WILL CONTINUE TO WATCH THE TRENDS THE NEXT COUPLE OF DAYS. BY
TUESDAY THE LOW, WHATEVER STRENGTH IT BECOMES, WILL BE TO OUR
NORTHEAST AND ANOTHER SHOT OF CANADIAN AIR SPILLS BACK INTO THE
REGION. COULD SEE SOME SNOW SHOWERS ON THE BACKSIDE OF THE SYSTEM
EARLY TUESDAY WITH STRONG NORTHWEST WINDS KICKING BACK IN.
WEDNESDAY...DRY DAY EXPECTED WITH RIDGING MOVING BACK IN BUT WITH
AN EVEN COLDER AIR MASS EXPECTED TO BE IN PLACE. HIGHS MAY NOT
REACH 40F IN A LOT OF PLACES.
&&
.AVIATION /15Z THURSDAY THROUGH MONDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
TODAY...CIGS BETWEEN 6000 AND 8000 FT RAPIDLY OVERSPREADING THE
REGION FROM SW TO NE. LIGHT N TO NORTHWEST WIND. RAIN SHOULD
DEVELOP AFTER 22Z SOUTHERN TERMINALS.
TONIGHT...MVFR OR LOWER POSSIBLE IN -RA....EXCEPT RAIN CHANGING
TO SNOW KRDG/KABE WITH A SMALL ACCUMULATION POSSIBLE BY 05Z WHILE
RAIN SHOULD END AS WET SNOW WITH LITTLE OR NO ACCUM DURING THE
PCPN KTTN/ KPNE/KPHL/KILG. IT IS POSSIBLE THAT KPHL-KTTN WILL SEE
AN HOUR OF 1 MILE VSBY IN SNOW WITH JUST ABV FREEZING SFC TEMP
SOMETIME BETWEEN 03Z-07Z. BEST CHC FOR ACCUMULATIVE SNOW OF ONE
HALF INCH OR MORE ON PAVEMENT APPEARS TO BE KABE.
AFTER 08Z FRIDAY...ICY SPOTS MAY DEVELOP FROM LEFTOVER MOISTURE
TOWARD 10Z FRIDAY AS A STIFFENING NW WIND DEVELOPS....GUSTS TO 15
OR 20 MPH POSSIBLE AFTER 08Z FRIDAY.
OUTLOOK...
FRIDAY - SUNDAY...VFR. GUSTY NORTHWEST WINDS EXPECTED ON FRIDAY.
MONDAY - TUESDAY...CHANCE OF MVFR WITH RAIN AND SNOW. SOUTHERLY
WINDS INCREASE IN TIME.
&&
.MARINE...
SCA FOR LATER TONIGHT AND FRIDAY.
TODAY, NW TO N WINDS 10-15 KT BECOMING 5-10 KT BY THE AFTN.
TONIGHT...NW WINDS INCREASE WITH GUSTS 25-30 KT
EXPECTED...STARTING AROUND 03Z LOWER DE BAY AND DE ATLC WATERS
THEN PROGRESSING THROUGH THE NJ WATERS AROUND 06Z. WE LEFT GALE
FORCE GUSTS IN THE WATERS E OF DELAWARE FROM OUR WIND GUST TOOL AS
IT IS POSSIBLE THAT THERE COULD BE AN HOUR OR 2 OF GALE GUSTS NEAR
44009 EARLY FRIDAY MORNING.
OUTLOOK...
FRIDAY...CONTINUED SCA CONDITIONS WITH STRONG NORTHWEST WINDS AND
SEAS AROUND 4 TO 6 FEET.
SATURDAY - SUNDAY...SUB-SCA EXPECTED THOUGH SCA GUSTS MAY LINGER
INTO EARLY SATURDAY MORNING.
MONDAY...LOW END CHANCE OF SCA SEAS AS THE SURFACE FLOW INCREASES
FROM THE SOUTH.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO 6 PM EST FRIDAY
FOR ANZ450>453.
SMALL CRAFT ADVISORY FROM 9 PM THIS EVENING TO 6 PM EST FRIDAY
FOR ANZ430-431-454-455.
&&
$$
SYNOPSIS...HEAVENER
NEAR TERM...IOVINO
SHORT TERM...DRAG
LONG TERM...HEAVENER
AVIATION...DRAG/HEAVENER
MARINE...DRAG/HEAVENER
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
557 PM EST THU NOV 13 2014
.SYNOPSIS...
A STRONG COLD FRONT WILL CROSS THE AREA TONIGHT WITH A LARGE AREA OF
CANADIAN HIGH PRESSURE BUILDING IN FRIDAY THROUGH SATURDAY. THE HIGH
WILL WEAKEN AND RETREAT TO THE NORTHEAST ON SUNDAY IN ADVANCE OF A
LOW PRESSURE SYSTEM EXPECTED TO AFFECT THE AREA ON MONDAY. ANOTHER
AREA OF CANADIAN HIGH PRESSURE WILL BUILD IN AND PREVAIL THROUGH
LATE NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
A COMPLEX SURFACE PATTERN IS IN PLACE ACROSS THE SOUTHEAST U.S.
THIS EVENING. MESOANALYSIS AT 13/22Z PLACED A 1011 HPA SURFACE LOW
VERY NEAR LITTLE RIVER INLET WITH A WEAK COLD FRONT EXTENDING
SOUTHWEST FROM THE LOW...ESSENTIALLY PARALLELING SOUTH CAROLINA
AND GEORGIA COASTS. AN AREA OF INTENSIFYING SURFACE FRONTOGENESIS
PER 13/21Z RAP FGEN VECTORS STRETCHED WEST ACROSS THE SOUTH
CAROLINA PEE DEE AND NORTHERN MIDLANDS INTO THE UPSTATE FROM THE
WEAK SURFACE CYCLONE. THIS FEATURE WILL BECOME A STRONGER...SECONDARY
COLD FRONT LATER TONIGHT AS MID-LEVEL COLD AIR ADVECTION
INTENSIFIES AND FURTHER PUSHES COLD AIR AROUND AND EVENTUALLY OVER
THE SOUTHERN APPALACHIANS IN THE WAKE OF THE DEPARTING LOW. THE
PRIMARY COLD FRONT WILL PUSH OFF THE COAST OVER THE NEXT 1-2 HOURS
AND BE FOLLOWED BY THE SECONDARY COLD FRONT DURING THE EARLY
MORNING HOURS FRIDAY.
THE VARIOUS FRONTAL PASSES THROUGH THE NIGHT POSES A PARTICULAR
FORECAST CHALLENGE TO HOURLY TEMPERATURES. SHOULD ONLY SEE A
SLIGHT TEMPERATURE FALL IN THE WAKE OF THE FIRST FRONT WITH A
STEEPER THERMAL DECLINES OCCURRING LATE AS STRONG COLD AIR ADVECTION
ENSUES IN THE WAKE OF THE SECONDARY COLD FRONT. THE COOLEST LOWS
WILL ACTUALLY BE FOUND ACROSS INTERIOR SOUTHEAST GEORGIA AND THE
CHARLESTON TRI-COUNTY AREA EARLY FRIDAY WITH A WARMER CORRIDOR
STRETCHING ACROSS JASPER...BEAUFORT...SOUTHERN COLLETON AND LOWER
CHARLESTON COUNTIES. LOWS WILL RANGE FROM THE UPPER 30S/LOWER 40S
SOUTHWEST AND NORTHERN AREAS TO THE UPPER 40S/NEAR 50 ACROSS THE
AFOREMENTIONED AREAS AROUND BEAUFORT COUNTY.
CHANCES FOR MEASURABLE RAIN WILL REMAIN QUITE LOW...ALTHOUGH A FEW
SPRINKLES CAN NOT BE COMPLETELY RULED OUT. GRIDDED POPS OF 10
PERCENT OR LESS WILL BE MAINTAINED.
FOR THE EARLY EVENING UPDATE...
1. ADJUSTED HOURLY TEMPERATURES PER LATEST GLAMP...RAP AND H3R
THERMAL TRENDS.
2. REMOVED MENTION OF SPRINKLES AS THIS PHENOMENA WILL NOT LAST
MORE THAN A FEW MINUTES FOR ANY ONE LOCATION.
3. ADJUSTED WINDS SLIGHTLY BASED ON THE EXPECTED PASSAGES OF THE
PRIMARY AND SECONDARY FRONTS.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY/...
A BROAD ZONAL FLOW ALOFT WILL FACILITATE STRONG CANADIAN HIGH
PRESSURE DROPPING INTO THE SOUTHEAST UNITED STATES FRIDAY INTO
SATURDAY. ALTHOUGH THE INITIAL COLD FRONT WILL BE OFFSHORE BY
DAYBREAK...THE PRIMARY BOUNDARY WILL LINGER BEHIND AND MOVE OFF THE
COAST LATE FRIDAY MORNING. STRONG COLD AND DRY ADVECTION WILL RESULT
IN A CHILLY DAY ON FRIDAY WITH HIGH TEMPS IN THE MIDDLE 50S. THE
THICKNESS PROGS ACTUALLY GIVE LOWER 50S IN MOST AREAS BUT THE
ADDITION OF WEAK DOWNSLOPE FLOW WILL PUSH TEMPS A FEW DEGREES HIGHER.
STRONG COLD AIR ADVECTION CONTINUES INTO FRIDAY NIGHT WITH 5-10 KT
NORTHERLY FLOW PERSISTING. ALTHOUGH THE MIXED BOUNDARY LAYER WILL
REDUCE THE EFFECTS OF RADIATIONAL COOLING...CLEAR SKIES WILL ONLY
HELP TEMPS PLUMMET AFTER DARK. WE ARE STILL SHOWING OVERNIGHT LOWS
IN THE UPPER 20S FAR INLAND WITH READINGS AT OR SLIGHTLY BELOW
FREEZING IN MANY LOCATIONS AWAY FROM THE GA COAST AND SC BEACHES.
BASED ON OUR GREATER THAN 50 PERCENT CONFIDENCE IN FREEZING TEMPS
IN MUCH OF THIS AREA...WE ISSUED A FREEZE WATCH FOR FRIDAY NIGHT.
THE COLD AIRMASS WILL REMAIN OVER THE AREA THROUGH SATURDAY. DESPITE
SUNNY SKIES THE HIGHS WILL STILL ONLY MAKE IT TO THE MID 50S.
SATURDAY NIGHT INTO SUNDAY...WITH THE BUILDING UPPER TROUGH TO OUR
WEST THE SURFACE HIGH WILL SHIFT OFF THE COAST. LOW-LEVEL MOISTURE
AND POSITIVE THERMAL ADVECTION WILL BRING HIGHER SURFACE DEWPOINTS
AND HIGH TEMPS SUNDAY IN THE MID TO UPPER 60S. DIFLUENCE ALOFT WILL
ALLOW A WEAK COASTAL TROUGH TO DEVELOP...WITH ISOLATED SHOWERS
POSSIBLE OVER THE COASTAL WATERS AND IMMEDIATE SC COAST.
LAKE WINDS...IT CONTINUES TO APPEAR THAT THE STRONGEST WINDS OVER
LAKE MOULTRIE WILL OCCUR FRIDAY NIGHT AS THE PRESSURE GRADIENT
TIGHTENS AND COLD AIR MOVES OVER THE RELATIVELY WARM LAKE WATERS.
WE STILL ARE FORECASTING WIND GUSTS JUST BELOW LAKE WIND ADVISORY
CRITERIA BUT WILL MAINTAIN MENTION OF THE POSSIBILITY IN THE
HAZARDOUS WEATHER OUTLOOK.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
THE FIRST PART OF THE LONG TERM PERIOD WILL BE A BIT ACTIVE AS THE
CORE OF A DEEP TROUGH DIVES OUT OF CENTRAL CANADA AND HELPS SPREAD
SHORTWAVE ENERGY ACROSS THE GULF COAST AND SOUTHEAST. AN AREA OF LOW
PRESSURE WILL DEVELOP ALONG THE GULF COAST EARLY MONDAY AND THEN
QUICKLY RIDE NORTHEAST ALONG THE FRONT IN THE LEE OF THE
APPALACHIANS. THIS WILL SPREAD A RELATIVELY QUICK SHOT OF MOISTURE
INTO THE AREA WITH GOOD FORCING...ESPECIALLY FOR THE LATTER PART OF
MONDAY AND INTO MONDAY NIGHT. POPS HAVE BEEN KEPT IN THE 50 PERCENT
RANGE FOR NOW...BUT GIVEN SUFFICIENT CONTINUED MODEL AGREEMENT RAIN
CHANCES WILL LIKELY RISE WITH FUTURE FORECAST UPDATES. SINCE WE LOOK
TO BE SOLIDLY IN THE WARM SECTOR...ISOLATED THUNDER HAS BEEN ADDED
TO THE FORECAST MONDAY AFTERNOON AND THEN FOR THE COASTAL WATERS
MONDAY NIGHT. BEHIND THE COLD FRONT...CONFIDENCE IS INCREASING IN AN
IMPRESSIVE ARCTIC BLAST TUESDAY ONWARD. IN FACT...RAW MODEL
THICKNESS VALUES FROM THE ECMWF WOULD ONLY SUPPORT HIGHS IN THE LOW
TO MID 40S BY WEDNESDAY. TEMPERATURES HAVE BEEN TRENDED DOWN TO
FEATURE HIGHS AND LOWS APPROACHING 20 DEGREES BELOW NORMAL. ALSO...
IT LOOKS LIKELY THAT A HARD FREEZE WILL OCCUR JUST ABOUT EVERYWHERE
ESPECIALLY AS THE HIGH MOVES OVERHEAD AND SETS UP IDEAL RADIATIONAL
COOLING CONDITIONS.
&&
.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
MAINLY VFR. WILL LIKELY SEE A PERIOD OF MVFR CIGS AT KCHS FROM
10-13Z AND 13-15Z AT KSAV IN THE WAKE OF THE SECONDARY COLD FRONT.
NO MAJOR IMPACTS ARE EXPECTED.
EXTENDED AVIATION OUTLOOK...MVFR CEILINGS POSSIBLE SATURDAY NIGHT
AND SUNDAY MORNING AS A WEAK COASTAL TROUGH MOVES INLAND. INCREASING
CHANCES FOR CEILING REDUCTIONS SUNDAY NIGHT THROUGH MONDAY AS A LOW
PRESSURE SYSTEM AFFECTS THE AREA.
&&
.MARINE...
TONIGHT...DETERIORATING MARINE CONDITIONS EXPECTED AS A
STRONG...SECONDARY COLD FRONT PUSHES SOUTHWARD THROUGH THE
WATERS...MAINLY AFTER MIDNIGHT. WINDS LIKELY TO GUST NEAR ADVISORY
LEVELS /25 KT/ BEYOND 20 NM AND THUS WE HAVE RAISED A SMALL CRAFT
ADVISORY FOR THE OUTER GA WATERS. SEAS WILL ALSO BUILD BUT BE
LIMITED BY THE OFFSHORE WINDS...PROBABLY PEAKING AT 5 FT OUT NEAR
40 NM OFF THE NORTHERN GA COAST.
FRIDAY THROUGH TUESDAY...THE PRIMARY WIND SURGE BEHIND THE COLD
FRONT WILL OCCUR FRIDAY INTO FRIDAY NIGHT AS COLD NORTHERLY WINDS
AFFECT THE WATERS. 20-30 KT GEOSTROPHIC WINDS OVER FAR
NORTHEASTERN CHARLESTON WATERS AND THE OFFSHORE GA WATERS JUSTIFY
THE ISSUANCE OF A SMALL CRAFT ADVISORY FOR BOTH ZONES DUE TO
FREQUENT 25 KT WIND GUSTS. WIND GUSTS ACROSS THE REMAINDER OF THE
NEARSHORE WATERS MAY BE CLOSE TO 25 KT AT TIMES...ESPECIALLY
FRIDAY NIGHT BUT WILL LET LATER SHIFTS MONITOR MODEL TRENDS.
MARINE CONDITIONS IMPROVE GREATLY SATURDAY NIGHT INTO SUNDAY AS THE
SURFACE HIGH BUILDS CLOSER TO THE WATERS AND THE GRADIENT RELAXES.
A LOW PRESSURE SYSTEM AND ASSOCIATED COLD FRONT WILL THEN AFFECT THE
REGION MONDAY WITH INCREASING SOUTHWESTERLY WINDS IN ADVANCE.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...FREEZE WATCH FROM LATE FRIDAY NIGHT THROUGH SATURDAY MORNING
FOR GAZ087-088-099>101-114>116-118-137-138.
SC...FREEZE WATCH FROM LATE FRIDAY NIGHT THROUGH SATURDAY MORNING
FOR SCZ040-042>045-047>052.
MARINE...SMALL CRAFT ADVISORY FROM 6 AM FRIDAY TO NOON EST SATURDAY FOR
AMZ350.
SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO 7 PM EST
SATURDAY FOR AMZ374.
&&
$$
ST
AREA FORECAST DISCUSSION
NWS POCATELLO ID
851 PM MST FRI NOV 14 2014
.UPDATE...HAVE MADE A FEW ADJUSTMENTS THROUGH THE EVENING AS FINAL
STAGES OF EARLY WINTER STORM IMPACTS EAST IDAHO. CURRENT RADAR/SAT
SHOWS MAIN BAND OF PRECIP STILL IN PLACE OVER SOUTHERN HIGHLANDS.
STRATUS THRU SNAKE PLAIN ALONG WITH POCKETS OF DENSE FREEZING FOG
ACROSS THE REGION. WEAK BAND OF LIGHT SNOW HAS DEVELOPED IN
ROUGHLY THE APPROPRIATE PLACE FOR CONVERGENCE ZONE. PRESSURE FIELD
NOT QUITE FAVORABLE BUT MESONET OBSERVATIONS SHOWING SOME
CONVERGENCE AT SURFACE. JUST ENOUGH FORCING WITH UPSLOPE FLOW OVER
EASTERN HIGHLANDS IN COMBINATION WITH SATURATED LOW LEVELS. MODELS
STILL HAVING A HARD TIME WITH THIS BAND. NAM PICKS IT UP AND SAGS
IT SOUTH OVERNIGHT INTO THE SOUTHERN HIGHLANDS. LOCAL WRF DID NOT
HAVE IT PREVIOUS RUN BUT WAITING ON 00Z TO SEE. HRRR SHOWING WEAK
PRECIP NEXT COUPLE HOURS BUT ORGANIZES THE BAND AND STRENGTHENS IT
BEFORE DROPPING IT ALONG THE I15 CORRIDOR THROUGH ABOUT SUNRISE.
DESPITE HAVING ALLOWED EARLIER ADVISORY FOR SNAKE PLAIN TO
EXPIRE...WILL WORK UP A NEW WINTER WX ADVISORY FOR AREAS EXPECTED
TO BE IMPACTED BY THIS BAND. ROADS ALREADY ICY FROM PRIOR SNOW
/SNOW-RAIN/MELTING AND REFREEZING. A NEW SKIFF OF SNOW ON TOP OF
THAT COULD BE DEADLY TO UNSUSPECTING DRIVERS. WITH THAT...WILL
EXTEND THE SOUTHERN/EASTERN HIGHLANDS ADVISORY OUT UNTIL 12Z TO
CATCH REMNANTS OF CURRENT BAND. DMH
&&
.PREV DISCUSSION... /ISSUED 154 PM MST FRI NOV 14 2014/
SHORT TERM...TODAY THROUGH SATURDAY AFTERNOON.
RADAR AND CURRENT OBSERVATIONS SHOW RAIN AND SNOW CONTINUING
ACROSS MUCH OF EASTERN IDAHO. WE HAVEN`T RECEIVED ANY REPORTS OF
FREEZING RAIN IN SEVERAL HOURS...BUT POCKETS OF IT ARE STILL
POSSIBLE ALONG/JUST NORTH OF A WARM FRONT. AS OF 140PM...THAT
BOUNDARY EXTENDS ALONG A KINSEY BUTTE-CRATERS-BLACKFOOT-BONE-
ANTELOPE FLATS-VICTOR LINE. IT SHOULDN`T MAKE ANY SIGNIFICANT
PROGRESS NORTH AS WE ALREADY SEEING COLDER AIR PUSH BACK SOUTH AND
EAST NEAR MOUNTAIN HOME AND ALSO ACROSS THE CENTRAL MOUNTAINS.
CURRENTLY SOUTH OF THE WARM FRONT...WE HAVE SEEN MORE RAIN THAN
SNOW AND WET ROADS. ELSEWHERE...ROADS ARE A MIX OF
SNOWCOVERED...SLUSHY AND WET EVEN WITH SNOW FALLING. AS THE COLD
FRONT PUSHES ACROSS OVER THE NEXT FEW HOURS...WE WILL SEE A CHANGE
BACK TO SNOW. BEHIND IT...LOCAL WIND STUDY INDICATES NEAR WIND
ADVISORY LEVEL WIND SPEEDS THAT CONTINUE BEYOND MIDNIGHT. THE AIR
MASS BEHIND THE FRONT IS QUITE COLD...INDICATED BY THE SINGLE
DIGIT AND LOW TEEN LOWS EXPECTED FOR TONIGHT. SAT AFTERNOON HIGHS
WILL STRUGGLE TO REACH 20 DEGREES AT THE SNAKE RIVER PLAIN LEVEL.
A HIGH AMPLITUDE RIDGE DEVELOPS ON SATURDAY AND THE BITTER COLD
AIR CONTINUES TO FUNNEL INTO THE FORECAST AREA...LOOK FOR MANY
BELOW ZERO TEMPERATURES IN THE SNAKE RIVER PLAIN.
IN TERMS OF ADDITIONAL SNOWFALL THROUGH THIS EVENING...FOR THE
CENTRAL MOUNTAINS EXPECT TRACE AMOUNTS MOST LOCATIONS WITH AN INCH
OR SO POSSIBLE NEAR CHALLIS AND ACROSS THE LOST RIVER/PAHSIMEROI
REGION. THE SNAKE PLAIN/MAGIC VALLEY WILL SEE ANYWHERE FROM A
TRACE TO LOCALLY 2 INCHES AS THE SWITCHOVER OCCURS. THE SOUTHERN
HIGHLANDS WILL SEE TRACE AMOUNTS IN THE VALLEYS AND 2-4 INCHES
ABOVE 5000FT. THE EASTERN HIGHLANDS CAN EXPECT 1-4 INCHES IN THE
VALLEYS AND UP TO 7 IN THE MOUNTAINS. WITH SOME WIND...WE SHOULD
SEE SOME POCKETS OF BLOWING/DRIFTING AND REDUCED VISIBILITY.
ADDITIONAL AMOUNTS AFTER THAT WILL BE LESS THAN AN INCH GENERALLY
EXCEPT FOR PORTIONS OF THE SOUTHERN AND EASTERN HIGHLANDS COULD
SEE ANOTHER 1-3 INCHES BEFORE TAPERING OFF QUICKLY LATER SATURDAY.
ALL HEADLINES REMAIN IN PLACE WITH THE NEXT UPDATE COMING AT
AROUND 5PM. KEYES/MESSICK
LONG TERM...SUNDAY THROUGH FRIDAY. A STRONG RIDGE WILL BUILD INTO
THE REGION AND WILL KEEP CONDITIONS DRY BUT VERY COLD INTO MIDDLE OF
NEXT WEEK. EXPECT VERY SIMILAR TEMPS TO THE RECENT COLD OUTBREAK
WITH LOWS IN THE SINGLE DIGITS OR BELOW ZERO AND HIGHS IN THE
20S. MODELS CONTINUE TO HAVE PROBLEMS HANDLING THE NEXT SYSTEM. MAIN
PROBLEM IS RUN TO RUN CONTINUITY AS SOME RUNS TRY TO KEEP THE RIDGE
INTACT WHILE OTHER RUNS BREAK DOWN THE RIDGE AND ALLOW A SHORTWAVE
TO BRING PRECIPITATION INTO THE REGION. CONTINUE TO MENTION LOW
CHANCE POPS AT THIS POINT...BUT CHANCES COULD EASILY GO UP OR DOWN
WHEN MODELS DEVELOP BETTER AGREEMENT.
VALLE
AVIATION...A SECOND WAVE OF PRECIPITATION WILL GIVE A GLANCING BLOW
TO THE TWO SOUTHERN AIRPORTS...WHILE NORTHERLY COMPONENT WINDS AT
KSUN AND KIDA WILL PUT THOSE AIRDROMES IN A PRECIPITATION SHADOW.
WINDY CONDITIONS WILL LINGER UNTIL LATE TONIGHT IN THE SNAKE RIVER
PLAIN. THE WINDS WILL FORTUNATELY KEEP FOG FROM HAVING A SEVERE
IMPACT ON VSBY...AND WHY IT WILL MORE LIKELY BE STRATUS TROUBLE. ALL
LOCATIONS THOUGH SHOULD BECOME CIG UNLIMITED BY THE LATE MORNING ON
SAT. MESSICK
&&
.PIH WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 11 PM MST THIS EVENING IDZ022>025.
&&
$$
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
1210 PM EST THU NOV 13 2014
.SYNOPSIS...
ISSUED AT 455 AM EST THU NOV 13 2014
LAKE EFFECT SNOW SHOWERS WILL PERSIST TODAY AND TONIGHT.
ACCUMULATIONS OF 1 TO 4 INCHES ARE POSSIBLE THROUGH FRIDAY MORNING
IN THE LAKE EFFECT REGION. ELSEWHERE...SCATTERED FLURRIES ARE
POSSIBLE AS AN UPPER LEVEL DISTURBANCE APPROACHES FROM THE UPPER
MISSISSIPPI VALLEY. HIGH TEMPERATURES TODAY WILL ONLY BE IN THE
LOWER 30S. LOWS TONIGHT WILL ONCE AGAIN BE IN THE 20S.
&&
.UPDATE...
ISSUED AT 958 AM EST THU NOV 13 2014
INCREASED SNOW AMOUNTS AND ISSUED A WINTER WX ADVISORY FOR TODAY
ACROSS NW ZONES GIVEN RADAR TRENDS/SPOTTER REPORTS/ROAD
CLOSERS...ESPECIALLY IN THE SOUTH BEND AREA. ADDED MOISTURE/ASCENT
WITH PASSAGE OF MID LEVEL TROUGH AXIS AND EXTREME INSTABILITY HAS
BEEN ENOUGH TO OVERCOME DRY LOW LEVELS/POOR FETCH SO FAR THIS
MORNING. LATEST NAM BUFR SOUNDINGS ALSO SHOW OMEGA AND
SUPERSATURATION WITH RESPECT TO ICE ALIGNED NICELY WITHIN LOWER
PART OF DGZ THROUGH THE AFTN FOR DECENT RATIOS/SNOW PRODUCTION.
WITH THAT SAID...INCREASE IN LARGE SCALE SUBSIDENCE/DRYING AND
DIURNAL CYCLE DISRUPTIONS SHOULD HOPEFULLY SUPPORT LESS
ORGANIZATION/IMPACTS AND POTENTIAL FOR A BRIEF LULL BY THIS
AFTERNOON.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 450 AM EST THU NOV 13 2014
LAKE EFFECT MACHINE FINALLY CRANKING UP EARLY THIS MORNING WITH
PASSAGE OF SHORT WAVE TROUGH AND LITTLE COLDER AIR AND SLIGHTLY
BETTER FETCH. EXPECT SNOW SHOWERS TO PERSIST THROUGH THE DAY AND
TONIGHT ACROSS FAVORED NORTHWEST FLOW COUNTIES. THIS FLOW WILL
RESULT IN A MULTI BAND SETUP WITH LIMITED FETCH IN THE 280-300
RANGE. COULD SEE SOME BRIEF INTENSE BANDS TODAY AND TONIGHT AS
INVERSION HEIGHTS RISE TO 10KFT AND SFC-850MB DELTA TS NEAR 20C AND
SFC-700MB NEAR 30C. FOLLOWING HIRES RAP AND HRRR GUIDANCE FOR TODAY
EXPECT TO SEE MULTIBANDS PRODUCE GENERAL 1 TO 2 INCH AMOUNTS.
SIMILAR AMOUNTS TONIGHT AS WELL FOR A TOTAL OF 2 TO 4 INCHES BY
EARLY FRIDAY MORNING. EXPECT SURFACE PAVEMENT TEMPS TO RISE ABOVE
FREEZING TODAY WITH AIR TEMPS NEAR OR JUST BELOW FREEZING. THIS
SHOULD KEEP MAIN ROADS WET WITH POSSIBLE ICY SPOTS RATHER THAN SNOW
COVERED. AS TEMPS FALL THIS EVENING...REMAINING SNOW BANDS SHOULD
START TO PRODUCE A COVERING ON ALL SURFACES. HAVE OPTED TO HOLD OFF
ON ANY ADVISORY HEADLINES WITH THIS PACKAGE WITH MOST CONCERN
FOCUSED ON TONIGHT PERIOD WITH COLDER TEMPS AND ROADS THEN BECOMING
SNOW COVERED AND SLICK. WILL DEFER ANY HEADLINES FOR TONIGHT TO DAY
SHIFT WITH FURTHER MONITORING OF WHERE BANDS PERSIST. WILL
ISSUE A SPECIAL WEATHER STATEMENT TO MENTION POSSIBLE ICY CONDITIONS
THIS MORNING WITH ACCUMULATING SNOW.
VERY COLD TEMPERATURES TODAY WITH HIGHS NEAR OR BELOW
FREEZING...ABOUT 20 DEGREES BELOW NORMAL. LOWS TONIGHT WILL AGAIN BE
DOWN TO AROUND 20 FAR SOUTH WHERE SOME PARTIAL CLEARING POSSIBLE AND
IN THE MIDDLE TO UPPER 20S NORTH UNDER LAKE CLOUDS.
&&
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 450 AM EST THU NOV 13 2014
AMAZING HIGH LATITUDE BLOCK UPSTREAM WITH A FULL 4 STANDARDIZED
DEVIATIONS/ANOMALIES PER PAST CLIMATE WAS HELPING TO INSURE
TEMPERATURES WILL STAY WELL BELOW NORMAL DOWNSTREAM INCLUDING THE
WESTERN GREAT LAKES REGION. INHERENT WITH THIS PATTERN ARE LAKE
EFFECT SNOW CHALLENGES WITH ACCOMPANYING NEARLY FRIGID AIR AS DELTA
T VALUES RANGE FROM 18C TO 25C FOR THE ENTIRE LONG TERM PERIOD.
INVERSION HEIGHTS WILL FALL FRIDAY...CAUSING LAKE EFFECT SNOW
SHOWERS TO DIMINISH AND EVENTUALLY BUT TEMPORARILY END. SOME LIGHT
SYSTEM SNOW IS EXPECTED SATURDAY NIGHT AS AN UPPER LEVEL TROF MOVES
ACROSS THE AREA. USING THE GARCIA METHOD ON THE 285K/GFS SURFACE
YIELDS AROUND AN INCH OF SNOW BY SUNDAY MORNING. A SECOND ARCTIC
SURGE OF EVEN COLDER AIR WILL CREATE FAVORABLE CONDITIONS FOR MORE
LAKE EFFECT SNOW EARLY NEXT WEEK. HAVE INCREASED LAKE EFFECT SNOW
CHANCES MONDAY THROUGH WEDNESDAY AS INVERSION HEIGHTS RISE AND THE
FETCH BECOMES MORE FAVORABLE FOR SNOW SHOWERS. GFS/BUFKIT INDICATES
THE EQUILIBRIUM LEVEL OF LAKE INDUCED CAPE RISING TO 10K FEET WITH
THE DENDRITIC GROWTH ZONE OVERLAYING THE CLOUD LAYER. GIVEN THE
FETCH...MORE OF A MULTI/BAND EVENT IS EXPECTED IN LIEU OF A SINGLE
BAND. AS FOR TEMPERATURES...ONGOING HIGHS OF GENERALLY 29F TO 35F
FRIDAY THROUGH SUNDAY FOLLOWED BY HIGHS IN THE MID TO UPPER 20S
MONDAY AND TUESDAY APPEAR ON TRACK. THE COLDEST HIGH RECORD FOR
TUESDAY AT FT WAYNE NOVEMBER 18 IS 26F. HAVE LOWERED THE HIGH TO
26F...THE CANADIAN GEM EPS GRAM AND ECMWF TEMPERATURE GUIDANCE
SUPPORTS HIGHS OF ONLY 22F TO 24F. 850 MB TEMPS SHOULD BE CLOSE TO
-18C TUESDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1209 PM EST THU NOV 13 2014
LAKE EFFECT SNOW SHOWERS AND CIGS RANGING BTW HIGH MVFR-LOW VFR
WILL CONTINUE TO IMPACT NORTHERN INDIANA THROUGH THE FORECAST
PERIOD. GREATEST IMPACT FROM THE SNOW SHOWER ACTIVITY WILL
CONTINUE TO BE AT KSBN WHERE VISIBILITIES WILL BE HIGHLY VARIABLE
THROUGH THE PERIOD. KFWA WILL ALSO SEE A FEW FLURRIES/SNOW SHOWERS
MAINLY THIS AFTN WHICH MAY BRIEFLY REDUCE VISIBILITIES.
OTHERWISE...WNW WINDS 10-16 KTS THIS AFTN WILL LESSEN TO BTW 6-12
KTS TONIGHT.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...WINTER WEATHER ADVISORY UNTIL 7 PM EST /6 PM CST/ THIS EVENING
FOR INZ003>005.
MI...WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR
MIZ077>079.
OH...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 5 PM EST FRIDAY FOR LMZ043-046.
&&
$$
UPDATE...STEINWEDEL
SYNOPSIS...LASHLEY
SHORT TERM...LASHLEY
LONG TERM...SKIPPER
AVIATION...STEINWEDEL
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSNORTHERNINDIANA
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
959 AM EST THU NOV 13 2014
.SYNOPSIS...
ISSUED AT 455 AM EST THU NOV 13 2014
LAKE EFFECT SNOW SHOWERS WILL PERSIST TODAY AND TONIGHT.
ACCUMULATIONS OF 1 TO 4 INCHES ARE POSSIBLE THROUGH FRIDAY MORNING
IN THE LAKE EFFECT REGION. ELSEWHERE...SCATTERED FLURRIES ARE
POSSIBLE AS AN UPPER LEVEL DISTURBANCE APPROACHES FROM THE UPPER
MISSISSIPPI VALLEY. HIGH TEMPERATURES TODAY WILL ONLY BE IN THE
LOWER 30S. LOWS TONIGHT WILL ONCE AGAIN BE IN THE 20S.
&&
.UPDATE...
ISSUED AT 958 AM EST THU NOV 13 2014
INCREASED SNOW AMOUNTS AND ISSUED A WINTER WX ADVISORY FOR TODAY
ACROSS NW ZONES GIVEN RADAR TRENDS/SPOTTER REPORTS/ROAD
CLOSERS...ESPECIALLY IN THE SOUTH BEND AREA. ADDED MOISTURE/ASCENT
WITH PASSAGE OF MID LEVEL TROUGH AXIS AND EXTREME INSTABILITY HAS
BEEN ENOUGH TO OVERCOME DRY LOW LEVELS/POOR FETCH SO FAR THIS
MORNING. LATEST NAM BUFR SOUNDINGS ALSO SHOW OMEGA AND
SUPERSATURATION WITH RESPECT TO ICE ALIGNED NICELY WITHIN LOWER
PART OF DGZ THROUGH THE AFTN FOR DECENT RATIOS/SNOW PRODUCTION.
WITH THAT SAID...INCREASE IN LARGE SCALE SUBSIDENCE/DRYING AND
DIURNAL CYCLE DISRUPTIONS SHOULD HOPEFULLY SUPPORT LESS
ORGANIZATION/IMPACTS AND POTENTIAL FOR A BRIEF LULL BY THIS
AFTERNOON.
&&
.SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 450 AM EST THU NOV 13
2014
LAKE EFFECT MACHINE FINALLY CRANKING UP EARLY THIS MORNING WITH
PASSAGE OF SHORT WAVE TROUGH AND LITTLE COLDER AIR AND SLIGHTLY
BETTER FETCH. EXPECT SNOW SHOWERS TO PERSIST THROUGH THE DAY AND
TONIGHT ACROSS FAVORED NORTHWEST FLOW COUNTIES. THIS FLOW WILL
RESULT IN A MULTI BAND SETUP WITH LIMITED FETCH IN THE 280-300
RANGE. COULD SEE SOME BRIEF INTENSE BANDS TODAY AND TONIGHT AS
INVERSION HEIGHTS RISE TO 10KFT AND SFC-850MB DELTA TS NEAR 20C AND
SFC-700MB NEAR 30C. FOLLOWING HIRES RAP AND HRRR GUIDANCE FOR TODAY
EXPECT TO SEE MULTIBANDS PRODUCE GENERAL 1 TO 2 INCH AMOUNTS.
SIMILAR AMOUNTS TONIGHT AS WELL FOR A TOTAL OF 2 TO 4 INCHES BY
EARLY FRIDAY MORNING. EXPECT SURFACE PAVEMENT TEMPS TO RISE ABOVE
FREEZING TODAY WITH AIR TEMPS NEAR OR JUST BELOW FREEZING. THIS
SHOULD KEEP MAIN ROADS WET WITH POSSIBLE ICY SPOTS RATHER THAN SNOW
COVERED. AS TEMPS FALL THIS EVENING...REMAINING SNOW BANDS SHOULD
START TO PRODUCE A COVERING ON ALL SURFACES. HAVE OPTED TO HOLD OFF
ON ANY ADVISORY HEADLINES WITH THIS PACKAGE WITH MOST CONCERN
FOCUSED ON TONIGHT PERIOD WITH COLDER TEMPS AND ROADS THEN BECOMING
SNOW COVERED AND SLICK. WILL DEFER ANY HEADLINES FOR TONIGHT TO DAY
SHIFT WITH FURTHER MONITORING OF WHERE BANDS PERSIST. WILL
ISSUE A SPECIAL WEATHER STATEMENT TO MENTION POSSIBLE ICY CONDITIONS
THIS MORNING WITH ACCUMULATING SNOW.
VERY COLD TEMPERATURES TODAY WITH HIGHS NEAR OR BELOW
FREEZING...ABOUT 20 DEGREES BELOW NORMAL. LOWS TONIGHT WILL AGAIN BE
DOWN TO AROUND 20 FAR SOUTH WHERE SOME PARTIAL CLEARING POSSIBLE AND
IN THE MIDDLE TO UPPER 20S NORTH UNDER LAKE CLOUDS.
&&
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 450 AM EST THU NOV 13 2014
AMAZING HIGH LATITUDE BLOCK UPSTREAM WITH A FULL 4 STANDARDIZED
DEVIATIONS/ANOMALIES PER PAST CLIMATE WAS HELPING TO INSURE
TEMPERATURES WILL STAY WELL BELOW NORMAL DOWNSTREAM INCLUDING THE
WESTERN GREAT LAKES REGION. INHERENT WITH THIS PATTERN ARE LAKE
EFFECT SNOW CHALLENGES WITH ACCOMPANYING NEARLY FRIGID AIR AS DELTA
T VALUES RANGE FROM 18C TO 25C FOR THE ENTIRE LONG TERM PERIOD.
INVERSION HEIGHTS WILL FALL FRIDAY...CAUSING LAKE EFFECT SNOW
SHOWERS TO DIMINISH AND EVENTUALLY BUT TEMPORARILY END. SOME LIGHT
SYSTEM SNOW IS EXPECTED SATURDAY NIGHT AS AN UPPER LEVEL TROF MOVES
ACROSS THE AREA. USING THE GARCIA METHOD ON THE 285K/GFS SURFACE
YIELDS AROUND AN INCH OF SNOW BY SUNDAY MORNING. A SECOND ARCTIC
SURGE OF EVEN COLDER AIR WILL CREATE FAVORABLE CONDITIONS FOR MORE
LAKE EFFECT SNOW EARLY NEXT WEEK. HAVE INCREASED LAKE EFFECT SNOW
CHANCES MONDAY THROUGH WEDNESDAY AS INVERSION HEIGHTS RISE AND THE
FETCH BECOMES MORE FAVORABLE FOR SNOW SHOWERS. GFS/BUFKIT INDICATES
THE EQUILIBRIUM LEVEL OF LAKE INDUCED CAPE RISING TO 10K FEET WITH
THE DENDRITIC GROWTH ZONE OVERLAYING THE CLOUD LAYER. GIVEN THE
FETCH...MORE OF A MULTI/BAND EVENT IS EXPECTED IN LIEU OF A SINGLE
BAND. AS FOR TEMPERATURES...ONGOING HIGHS OF GENERALLY 29F TO 35F
FRIDAY THROUGH SUNDAY FOLLOWED BY HIGHS IN THE MID TO UPPER 20S
MONDAY AND TUESDAY APPEAR ON TRACK. THE COLDEST HIGH RECORD FOR
TUESDAY AT FT WAYNE NOVEMBER 18 IS 26F. HAVE LOWERED THE HIGH TO
26F...THE CANADIAN GEM EPS GRAM AND ECMWF TEMPERATURE GUIDANCE
SUPPORTS HIGHS OF ONLY 22F TO 24F. 850 MB TEMPS SHOULD BE CLOSE TO
-18C TUESDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 629 AM EST THU NOV 13 2014
LAKE EFFECT SNOW SHOWERS ONGOING AND WILL CONTINUE THROUGH THE
PERIOD AT KSBN. VISIBILITIES WILL VARY DEPENDING ON WHEN THE BANDS
MOVE OVER THE AIRPORT. WILL HAVE A TEMPO GROUP TO START THE PERIOD
WITH IFR POSSIBLE. BANDS SHOULD WANE A LITTLE LATER IN THE DAY BUT
EXPECT ADDITIONAL TEMPO GROUP WILL BE NEEDED LATE MORNING INTO
AFTERNOON. SECOND WAVE EXPECTED THIS EVENING AND WILL BRING
ADDITIONAL SNOW SHOWERS OVERNIGHT. KFWA WILL SEE SOME LIGHT SNOW
SHOWERS OR FLURRIES AS A SHORT WAVE PASSES THROUGH. THEY ALSO MAY
SEE THE TAIL END OF SOME LAKE BANDS. TOO MUCH UNCERTAINTY FOR VIS
RESTRICTIONS AT THIS TIME BUT EXPECT SOME MVFR CIGS TO DEVELOP AND
MOVE IN LATER THIS MORNING WITH FLOW OFF THE LAKE.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...WINTER WEATHER ADVISORY UNTIL 7 PM EST /6 PM CST/ THIS EVENING
FOR INZ003>005.
MI...WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR
MIZ077>079.
OH...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 5 PM EST FRIDAY FOR LMZ043-046.
&&
$$
UPDATE...STEINWEDEL
SYNOPSIS...LASHLEY
SHORT TERM...LASHLEY
LONG TERM...SKIPPER
AVIATION...LASHLEY
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSNORTHERNINDIANA
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
727 AM EST THU NOV 13 2014
.SYNOPSIS...
ISSUED AT 455 AM EST THU NOV 13 2014
LAKE EFFECT SNOW SHOWERS WILL PERSIST TODAY AND TONIGHT.
ACCUMULATIONS OF 1 TO 4 INCHES ARE POSSIBLE THROUGH FRIDAY MORNING
IN THE LAKE EFFECT REGION. ELSEWHERE...SCATTERED FLURRIES ARE
POSSIBLE AS AN UPPER LEVEL DISTURBANCE APPROACHES FROM THE UPPER
MISSISSIPPI VALLEY. HIGH TEMPERATURES TODAY WILL ONLY BE IN THE
LOWER 30S. LOWS TONIGHT WILL ONCE AGAIN BE IN THE 20S.
&&
.SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 450 AM EST THU NOV 13
2014
LAKE EFFECT MACHINE FINALLY CRANKING UP EARLY THIS MORNING WITH
PASSAGE OF SHORT WAVE TROUGH AND LITTLE COLDER AIR AND SLIGHTLY
BETTER FETCH. EXPECT SNOW SHOWERS TO PERSIST THROUGH THE DAY AND
TONIGHT ACROSS FAVORED NORTHWEST FLOW COUNTIES. THIS FLOW WILL
RESULT IN A MULTI BAND SETUP WITH LIMITED FETCH IN THE 280-300
RANGE. COULD SEE SOME BRIEF INTENSE BANDS TODAY AND TONIGHT AS
INVERSION HEIGHTS RISE TO 10KFT AND SFC-850MB DELTA TS NEAR 20C AND
SFC-700MB NEAR 30C. FOLLOWING HIRES RAP AND HRRR GUIDANCE FOR TODAY
EXPECT TO SEE MULTIBANDS PRODUCE GENERAL 1 TO 2 INCH AMOUNTS.
SIMILAR AMOUNTS TONIGHT AS WELL FOR A TOTAL OF 2 TO 4 INCHES BY
EARLY FRIDAY MORNING. EXPECT SURFACE PAVEMENT TEMPS TO RISE ABOVE
FREEZING TODAY WITH AIR TEMPS NEAR OR JUST BELOW FREEZING. THIS
SHOULD KEEP MAIN ROADS WET WITH POSSIBLE ICY SPOTS RATHER THAN SNOW
COVERED. AS TEMPS FALL THIS EVENING...REMAINING SNOW BANDS SHOULD
START TO PRODUCE A COVERING ON ALL SURFACES. HAVE OPTED TO HOLD OFF
ON ANY ADVISORY HEADLINES WITH THIS PACKAGE WITH MOST CONCERN
FOCUSED ON TONIGHT PERIOD WITH COLDER TEMPS AND ROADS THEN BECOMING
SNOW COVERED AND SLICK. WILL DEFER ANY HEADLINES FOR TONIGHT TO DAY
SHIFT WITH FURTHER MONITORING OF WHERE BANDS PERSIST. WILL
ISSUE A SPECIAL WEATHER STATEMENT TO MENTION POSSIBLE ICY CONDITIONS
THIS MORNING WITH ACCUMULATING SNOW.
VERY COLD TEMPERATURES TODAY WITH HIGHS NEAR OR BELOW
FREEZING...ABOUT 20 DEGREES BELOW NORMAL. LOWS TONIGHT WILL AGAIN BE
DOWN TO AROUND 20 FAR SOUTH WHERE SOME PARTIAL CLEARING POSSIBLE AND
IN THE MIDDLE TO UPPER 20S NORTH UNDER LAKE CLOUDS.
&&
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 450 AM EST THU NOV 13 2014
AMAZING HIGH LATITUDE BLOCK UPSTREAM WITH A FULL 4 STANDARDIZED
DEVIATIONS/ANOMALIES PER PAST CLIMATE WAS HELPING TO INSURE
TEMPERATURES WILL STAY WELL BELOW NORMAL DOWNSTREAM INCLUDING THE
WESTERN GREAT LAKES REGION. INHERENT WITH THIS PATTERN ARE LAKE
EFFECT SNOW CHALLENGES WITH ACCOMPANYING NEARLY FRIGID AIR AS DELTA
T VALUES RANGE FROM 18C TO 25C FOR THE ENTIRE LONG TERM PERIOD.
INVERSION HEIGHTS WILL FALL FRIDAY...CAUSING LAKE EFFECT SNOW
SHOWERS TO DIMINISH AND EVENTUALLY BUT TEMPORARILY END. SOME LIGHT
SYSTEM SNOW IS EXPECTED SATURDAY NIGHT AS AN UPPER LEVEL TROF MOVES
ACROSS THE AREA. USING THE GARCIA METHOD ON THE 285K/GFS SURFACE
YIELDS AROUND AN INCH OF SNOW BY SUNDAY MORNING. A SECOND ARCTIC
SURGE OF EVEN COLDER AIR WILL CREATE FAVORABLE CONDITIONS FOR MORE
LAKE EFFECT SNOW EARLY NEXT WEEK. HAVE INCREASED LAKE EFFECT SNOW
CHANCES MONDAY THROUGH WEDNESDAY AS INVERSION HEIGHTS RISE AND THE
FETCH BECOMES MORE FAVORABLE FOR SNOW SHOWERS. GFS/BUFKIT INDICATES
THE EQUILIBRIUM LEVEL OF LAKE INDUCED CAPE RISING TO 10K FEET WITH
THE DENDRITIC GROWTH ZONE OVERLAYING THE CLOUD LAYER. GIVEN THE
FETCH...MORE OF A MULTI/BAND EVENT IS EXPECTED IN LIEU OF A SINGLE
BAND. AS FOR TEMPERATURES...ONGOING HIGHS OF GENERALLY 29F TO 35F
FRIDAY THROUGH SUNDAY FOLLOWED BY HIGHS IN THE MID TO UPPER 20S
MONDAY AND TUESDAY APPEAR ON TRACK. THE COLDEST HIGH RECORD FOR
TUESDAY AT FT WAYNE NOVEMBER 18 IS 26F. HAVE LOWERED THE HIGH TO
26F...THE CANADIAN GEM EPS GRAM AND ECMWF TEMPERATURE GUIDANCE
SUPPORTS HIGHS OF ONLY 22F TO 24F. 850 MB TEMPS SHOULD BE CLOSE TO
-18C TUESDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 629 AM EST THU NOV 13 2014
LAKE EFFECT SNOW SHOWERS ONGOING AND WILL CONTINUE THROUGH THE
PERIOD AT KSBN. VISIBILITIES WILL VARY DEPENDING ON WHEN THE BANDS
MOVE OVER THE AIRPORT. WILL HAVE A TEMPO GROUP TO START THE PERIOD
WITH IFR POSSIBLE. BANDS SHOULD WANE A LITTLE LATER IN THE DAY BUT
EXPECT ADDITIONAL TEMPO GROUP WILL BE NEEDED LATE MORNING INTO
AFTERNOON. SECOND WAVE EXPECTED THIS EVENING AND WILL BRING
ADDITIONAL SNOW SHOWERS OVERNIGHT. KFWA WILL SEE SOME LIGHT SNOW
SHOWERS OR FLURRIES AS A SHORT WAVE PASSES THROUGH. THEY ALSO MAY
SEE THE TAIL END OF SOME LAKE BANDS. TOO MUCH UNCERTAINTY FOR VIS
RESTRICTIONS AT THIS TIME BUT EXPECT SOME MVFR CIGS TO DEVELOP AND
MOVE IN LATER THIS MORNING WITH FLOW OFF THE LAKE.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 5 PM EST FRIDAY FOR LMZ043-046.
&&
$$
SYNOPSIS...LASHLEY
SHORT TERM...LASHLEY
LONG TERM...SKIPPER
AVIATION...LASHLEY
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSNORTHERNINDIANA
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
637 AM EST THU NOV 13 2014
.SYNOPSIS...
ISSUED AT 455 AM EST THU NOV 13 2014
LAKE EFFECT SNOW SHOWERS WILL PERSIST TODAY AND TONIGHT. ACCUMULATIONS
OF 1 TO 4 INCHES ARE POSSIBLE THROUGH FRIDAY MORNING IN THE LAKE
EFFECT REGION. ELSEWHERE...SCATTERED FLURRIES ARE POSSIBLE AS AN
UPPER LEVEL DISTURBANCE APPROACHES FROM THE UPPER MISSISSIPPI
VALLEY. HIGH TEMPERATURES TODAY WILL ONLY BE IN THE LOWER 30S.
LOWS TONIGHT WILL ONCE AGAIN BE IN THE 20S.
&&
.SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 450 AM EST THU NOV 13
2014
LAKE EFFECT MACHINE FINALLY CRANKING UP EARLY THIS MORNING WITH
PASSAGE OF SHORT WAVE TROUGH AND LITTLE COLDER AIR AND SLIGHTLY
BETTER FETCH. EXPECT SNOW SHOWERS TO PERSIST THROUGH THE DAY AND
TONIGHT ACROSS FAVORED NORTHWEST FLOW COUNTIES. THIS FLOW WILL
RESULT IN A MULTI BAND SETUP WITH LIMITED FETCH IN THE 280-300
RANGE. COULD SEE SOME BRIEF INTENSE BANDS TODAY AND TONIGHT AS
INVERSION HEIGHTS RISE TO 10KFT AND SFC-850MB DELTA TS NEAR 20C AND
SFC-700MB NEAR 30C. FOLLOWING HIRES RAP AND HRRR GUIDANCE FOR TODAY
EXPECT TO SEE MULTIBANDS PRODUCE GENERAL 1 TO 2 INCH AMOUNTS.
SIMILAR AMOUNTS TONIGHT AS WELL FOR A TOTAL OF 2 TO 4 INCHES BY
EARLY FRIDAY MORNING. EXPECT SURFACE PAVEMENT TEMPS TO RISE ABOVE
FREEZING TODAY WITH AIR TEMPS NEAR OR JUST BELOW FREEZING. THIS
SHOULD KEEP MAIN ROADS WET WITH POSSIBLE ICY SPOTS RATHER THAN SNOW
COVERED. AS TEMPS FALL THIS EVENING...REMAINING SNOW BANDS SHOULD
START TO PRODUCE A COVERING ON ALL SURFACES. HAVE OPTED TO HOLD OFF
ON ANY ADVISORY HEADLINES WITH THIS PACKAGE WITH MOST CONCERN
FOCUSED ON TONIGHT PERIOD WITH COLDER TEMPS AND ROADS THEN BECOMING
SNOW COVERED AND SLICK. WILL DEFER ANY HEADLINES FOR TONIGHT TO DAY
SHIFT WITH FURTHER MONITORING OF WHERE BANDS PERSIST. WILL
ISSUE A SPECIAL WEATHER STATEMENT TO MENTION POSSIBLE ICY CONDITIONS
THIS MORNING WITH ACCUMULATING SNOW.
VERY COLD TEMPERATURES TODAY WITH HIGHS NEAR OR BELOW
FREEZING...ABOUT 20 DEGREES BELOW NORMAL. LOWS TONIGHT WILL AGAIN BE
DOWN TO AROUND 20 FAR SOUTH WHERE SOME PARTIAL CLEARING POSSIBLE AND
IN THE MIDDLE TO UPPER 20S NORTH UNDER LAKE CLOUDS.
&&
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 450 AM EST THU NOV 13 2014
AMAZING HIGH LATITUDE BLOCK UPSTREAM WITH A FULL 4 STANDARDIZED
DEVIATIONS/ANOMALIES PER PAST CLIMATE WAS HELPING TO INSURE
TEMPERATURES WILL STAY WELL BELOW NORMAL DOWNSTREAM INCLUDING THE
WESTERN GREAT LAKES REGION. INHERENT WITH THIS PATTERN ARE LAKE
EFFECT SNOW CHALLENGES WITH ACCOMPANYING NEARLY FRIGID AIR AS DELTA
T VALUES RANGE FROM 18C TO 25C FOR THE ENTIRE LONG TERM PERIOD.
INVERSION HEIGHTS WILL FALL FRIDAY...CAUSING LAKE EFFECT SNOW
SHOWERS TO DIMINISH AND EVENTUALLY BUT TEMPORARILY END. SOME LIGHT
SYSTEM SNOW IS EXPECTED SATURDAY NIGHT AS AN UPPER LEVEL TROF MOVES
ACROSS THE AREA. USING THE GARCIA METHOD ON THE 285K/GFS SURFACE
YIELDS AROUND AN INCH OF SNOW BY SUNDAY MORNING. A SECOND ARCTIC
SURGE OF EVEN COLDER AIR WILL CREATE FAVORABLE CONDITIONS FOR MORE
LAKE EFFECT SNOW EARLY NEXT WEEK. HAVE INCREASED LAKE EFFECT SNOW
CHANCES MONDAY THROUGH WEDNESDAY AS INVERSION HEIGHTS RISE AND THE
FETCH BECOMES MORE FAVORABLE FOR SNOW SHOWERS. GFS/BUFKIT INDICATES
THE EQUILIBRIUM LEVEL OF LAKE INDUCED CAPE RISING TO 10K FEET WITH
THE DENDRITIC GROWTH ZONE OVERLAYING THE CLOUD LAYER. GIVEN THE
FETCH...MORE OF A MULTI/BAND EVENT IS EXPECTED IN LIEU OF A SINGLE
BAND. AS FOR TEMPERATURES...ONGOING HIGHS OF GENERALLY 29F TO 35F
FRIDAY THROUGH SUNDAY FOLLOWED BY HIGHS IN THE MID TO UPPER 20S
MONDAY AND TUESDAY APPEAR ON TRACK. THE COLDEST HIGH RECORD FOR
TUESDAY AT FT WAYNE NOVEMBER 18 IS 26F. HAVE LOWERED THE HIGH TO
26F...THE CANADIAN GEM EPS GRAM AND ECMWF TEMPERATURE GUIDANCE
SUPPORTS HIGHS OF ONLY 22F TO 24F. 850 MB TEMPS SHOULD BE CLOSE TO
-18C TUESDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 629 AM EST THU NOV 13 2014
LAKE EFFECT SNOW SHOWERS ONGOING AND WILL CONTINUE THROUGH THE
PERIOD AT KSBN. VISIBILITIES WILL VARY DEPENDING ON WHEN THE BANDS
MOVE OVER THE AIRPORT. WILL HAVE A TEMPO GROUP TO START THE PERIOD
WITH IFR POSSIBLE. BANDS SHOULD WANE A LITTLE LATER IN THE DAY BUT
EXPECT ADDITIONAL TEMPO GROUP WILL BE NEEDED LATE MORNING INTO
AFTERNOON. SECOND WAVE EXPECTED THIS EVENING AND WILL BRING
ADDITIONAL SNOW SHOWERS OVERNIGHT. KFWA WILL SEE SOME LIGHT SNOW
SHOWERS OR FLURRIES AS A SHORT WAVE PASSES THROUGH. THEY ALSO MAY
SEE THE TAIL END OF SOME LAKE BANDS. TOO MUCH UNCERTAINTY FOR VIS
RESTRICTIONS AT THIS TIME BUT EXPECT SOME MVFR CIGS TO DEVELOP AND
MOVE IN LATER THIS MORNING WITH FLOW OFF THE LAKE.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 5 PM EST FRIDAY FOR LMZ043-046.
&&
$$
SYNOPSIS...LASHLEY
SHORT TERM...LASHLEY
LONG TERM...SKIPPER
AVIATION...LASHLEY
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSNORTHERNINDIANA
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
456 AM EST THU NOV 13 2014
.SYNOPSIS...
ISSUED AT 455 AM EST THU NOV 13 2014
LAKE EFFECT SNOW SHOWERS WILL PERSIST TODAY AND TONIGHT. ACCUMULATIONS
OF 1 TO 4 INCHES ARE POSSIBLE THROUGH FRIDAY MORNING IN THE LAKE
EFFECT REGION. ELSEWHERE...SCATTERED FLURRIES ARE POSSIBLE AS AN
UPPER LEVEL DISTURBANCE APPROACHES FROM THE UPPER MISSISSIPPI
VALLEY. HIGH TEMPERATURES TODAY WILL ONLY BE IN THE LOWER 30S.
LOWS TONIGHT WILL ONCE AGAIN BE IN THE 20S.
.SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 450 AM EST THU NOV 13
2014
LAKE EFFECT MACHINE FINALLY CRANKING UP EARLY THIS MORNING WITH
PASSAGE OF SHORT WAVE TROUGH AND LITTLE COLDER AIR AND SLIGHTLY
BETTER FETCH. EXPECT SNOW SHOWERS TO PERSIST THROUGH THE DAY AND
TONIGHT ACROSS FAVORED NORTHWEST FLOW COUNTIES. THIS FLOW WILL
RESULT IN A MULTI BAND SETUP WITH LIMITED FETCH IN THE 280-300
RANGE. COULD SEE SOME BRIEF INTENSE BANDS TODAY AND TONIGHT AS
INVERSION HEIGHTS RISE TO 10KFT AND SFC-850MB DELTA TS NEAR 20C AND
SFC-700MB NEAR 30C. FOLLOWING HIRES RAP AND HRRR GUIDANCE FOR TODAY
EXPECT TO SEE MULTIBANDS PRODUCE GENERAL 1 TO 2 INCH AMOUNTS.
SIMILAR AMOUNTS TONIGHT AS WELL FOR A TOTAL OF 2 TO 4 INCHES BY
EARLY FRIDAY MORNING. EXPECT SURFACE PAVEMENT TEMPS TO RISE ABOVE
FREEZING TODAY WITH AIR TEMPS NEAR OR JUST BELOW FREEZING. THIS
SHOULD KEEP MAIN ROADS WET WITH POSSIBLE ICY SPOTS RATHER THAN SNOW
COVERED. AS TEMPS FALL THIS EVENING...REMAINING SNOW BANDS SHOULD
START TO PRODUCE A COVERING ON ALL SURFACES. HAVE OPTED TO HOLD OFF
ON ANY ADVISORY HEADLINES WITH THIS PACKAGE WITH MOST CONCERN
FOCUSED ON TONIGHT PERIOD WITH COLDER TEMPS AND ROADS THEN BECOMING
SNOW COVERED AND SLICK. WILL DEFER ANY HEADLINES FOR TONIGHT TO DAY
SHIFT WITH FURTHER MONITORING OF WHERE BANDS PERSIST. WILL
ISSUE A SPECIAL WEATHER STATEMENT TO MENTION POSSIBLE ICY CONDITIONS
THIS MORNING WITH ACCUMULATING SNOW.
VERY COLD TEMPERATURES TODAY WITH HIGHS NEAR OR BELOW
FREEZING...ABOUT 20 DEGREES BELOW NORMAL. LOWS TONIGHT WILL AGAIN BE
DOWN TO AROUND 20 FAR SOUTH WHERE SOME PARTIAL CLEARING POSSIBLE AND
IN THE MIDDLE TO UPPER 20S NORTH UNDER LAKE CLOUDS.
&&
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 450 AM EST THU NOV 13 2014
AMAZING HIGH LATITUDE BLOCK UPSTREAM WITH A FULL 4 STANDARDIZED
DEVIATIONS/ANOMALIES PER PAST CLIMATE WAS HELPING TO INSURE
TEMPERATURES WILL STAY WELL BELOW NORMAL DOWNSTREAM INCLUDING THE
WESTERN GREAT LAKES REGION. INHERENT WITH THIS PATTERN ARE LAKE
EFFECT SNOW CHALLENGES WITH ACCOMPANYING NEARLY FRIGID AIR AS DELTA
T VALUES RANGE FROM 18C TO 25C FOR THE ENTIRE LONG TERM PERIOD.
INVERSION HEIGHTS WILL FALL FRIDAY...CAUSING LAKE EFFECT SNOW
SHOWERS TO DIMINISH AND EVENTUALLY BUT TEMPORARILY END. SOME LIGHT
SYSTEM SNOW IS EXPECTED SATURDAY NIGHT AS AN UPPER LEVEL TROF MOVES
ACROSS THE AREA. USING THE GARCIA METHOD ON THE 285K/GFS SURFACE
YIELDS AROUND AN INCH OF SNOW BY SUNDAY MORNING. A SECOND ARCTIC
SURGE OF EVEN COLDER AIR WILL CREATE FAVORABLE CONDITIONS FOR MORE
LAKE EFFECT SNOW EARLY NEXT WEEK. HAVE INCREASED LAKE EFFECT SNOW
CHANCES MONDAY THROUGH WEDNESDAY AS INVERSION HEIGHTS RISE AND THE
FETCH BECOMES MORE FAVORABLE FOR SNOW SHOWERS. GFS/BUFKIT INDICATES
THE EQUILIBRIUM LEVEL OF LAKE INDUCED CAPE RISING TO 10K FEET WITH
THE DENDRITIC GROWTH ZONE OVERLAYING THE CLOUD LAYER. GIVEN THE
FETCH...MORE OF A MULTI/BAND EVENT IS EXPECTED IN LIEU OF A SINGLE
BAND. AS FOR TEMPERATURES...ONGOING HIGHS OF GENERALLY 29F TO 25F
FRIDAY THROUGH SUNDAY FOLLOWED BY HIGHS IN THE MID TO UPPER 20S
MONDAY AND TUESDAY APPEAR ON TRACK. THE COLDEST HIGH RECORD FOR
TUESDAY AT FT WAYNE NOVEMBER 18 IS 26F. HAVE LOWERED THE HIGH TO
26F...THE CANADIAN GEM EPS GRAM AND ECMWF TEMPERATURE GUIDANCE
SUPPORTS HIGHS OF ONLY 22F TO 24F. 850 MB TEMPS SHOULD BE CLOSE TO
-18C TUESDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1224 AM EST THU NOV 13 2014
NARROW BAND OF LIGHT SNOW HAS FORMED JUST WEST OF KFWA AND MAY
CLIP THIS SITE NEXT FEW HOURS. OBSERVATIONS UPSTREAM HAVE BEEN IN
THE 2-3SM MILE RANGE WITH LIGHT SNOW BUT KEPT KFWA MVFR AS LOWER
RESTRICTIONS WOULD BE BRIEF IF THEY OCCUR AT ALL. OTHERWISE CIGS
HOVERING AROUND THE 3KFT RANGE. LAKE EFFECT SNOW SHOWERS TO
INCREASE LATER AS WINDS VEER SLIGHTLY AND COLDER AIR ARRIVES.
KEPT KSBN TAF IN THE MVFR RANGE BUT ANY STRONGER BANDS COULD
PRODUCE BRIEF IFR VISIBILITIES. WILL HAVE TO MONITOR DEVELOPMENT
FOR UPDATES AS LOCATION UNCERTAIN AT THIS TIME. LAKE EFFECT TO
CONTINUE OFF AND ON TODAY AND TONIGHT BUT MAY SEE A BRIEF LULL
LATE TODAY AHEAD OF ANOTHER SHORT WAVE TO MOVE THROUGH THIS
EVENING.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 5 PM EST FRIDAY FOR LMZ043-046.
&&
$$
SYNOPSIS...MARSILI
SHORT TERM...LASHLEY
LONG TERM...SKIPPER
AVIATION...LASHLEY
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSNORTHERNINDIANA
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1128 AM CST THU NOV 13 2014
.UPDATE...
ISSUED AT 1123 AM CST THU NOV 13 2014
SOME MINOR ADJUSTMENTS HAVE BEEN MADE TO THE FORECAST.
WEB CAMS INDICATE A VERY MINOR ACCUMULATION IN THE DBQ AREA. AS
SUCH THE MINOR SNOWFALL AMOUNTS HAVE BEEN INCREASED A FEW TENTHS
OF AN INCH FOR THE AFTERNOON HOURS.
RAP TRENDS CONTINUE TO INDICATE MORE SNOW SHOWERS DURING THE
AFTERNOON LIKELY DURING THE MAXIMUM HEATING THAT CAN OCCUR THIS
AFTERNOON.
UPDATE ISSUED AT 1016 AM CST THU NOV 13 2014
A SIGNIFICANT REVISION HAS BEEN MADE TO THE FORECAST.
RADAR HAS FLURRIES AND SNOW SHOWERS ACROSS THE AREA IN ADVANCE OF
THE APPROACHING UPPER LEVEL DISTURBANCE. FORCING AND LIMITED
DAYTIME HEATING HAS CREATED NEW CLOUDS WITH AN INCREASE IN
COVERAGE OF THE FLURRIES AND SNOW SHOWERS.
IF TRENDS WITH THE RAP MODEL ARE CORRECT...SOME OF THE SNOW
SHOWERS SHOULD GET FAIRLY STRONG LATE THIS MORNING AND EARLY
AFTERNOON WITH THE POTENTIAL FOR MINOR ACCUMULATIONS IN SOME
LOCATIONS.
&&
.SYNOPSIS...
ISSUED AT 345 AM CST THU NOV 13 2014
LOWER CLOUDS HAVE ENVELOPED MUCH OF CWA FROM NORTH TO SOUTH WITH
APPROACH OF SHEARING UPPER LEVEL WAVE. OCCASIONAL FLURRIES ALSO
CONTINUE WITH SOME LIGHT SNOW SHOWERS PORTIONS OF SOUTHERN MN INTO
NORTHERN IA BRIEFLY REDUCING VSBYS TO AROUND 2-5SM. SFC ANALYSIS
SHOWS IMPRESSIVE AND ANOMALOUSLY STRONG ANTICYCLONE OF 1045+ MB
OVER PORTIONS OF NORTHERN ROCKIES... WITH COUPLE OF WEAK TROUGHS
OR WIND SHIFTS NOTED UPSTREAM ATTENDANT TO UPPER LEVEL DISTURBANCES
BEING SHUTTLED DOWN IN CYCLONIC FLOW. ITS STILL COLD... WITH
00Z DVN RAOB 850 TEMP OF -16.1C 3RD COLDEST 850 MB TEMP IN MONTH
OF NOVEMBER AT DVN... TIED WITH 2000 (11/21 00Z) AND 2005 (11/25
00Z)... WITH THE COLDEST BEING -16.8C IN 1997 (11/16 12Z).
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 345 AM CST THU NOV 13 2014
LOWER CLOUDS TO CONTINUE SAGGING SOUTHWARD THROUGH CWA AS SHEARING
UPPER LEVEL WAVE PASSES... AND MAY SEE SOME BREAKS FOR A TIME
THIS AM NORTH HALF... BUT SHOULD BE SHORT-LIVED WITH ANY DIURNAL
HEATING LENDING TO MORE LOW CLOUD DEVELOPMENT. THUS... CONTINUED
PT-MOCLDY SKIES ALONG WITH OCCASIONAL FLURRIES TDY. MAY SEE SOME
LIGHT SNOW SHOWERS DEVELOP BY MID-LATE AM THROUGH AFTN WITH APPROACH
OF SECONDARY SHORTWAVE CURRENTLY OVER NORTHERN WI... AND ALSO WITH
BUFR SOUNDINGS SHOWING STEEP LOW LEVEL LAPSE RATES EXTENDING UP
THROUGH THE DENDRITIC GROWTH ZONE FOR BRIEF REDUCED VSBYS WITH DUSTING
OR SO OF ACCUM POSSIBLE. AS MENTIONED EARLIER... ALREADY SEEING
VSBYS DROP DOWN IN RANGE OF 2-5SM OVER PORTIONS OF SOUTHERN MN EARLY
THIS AM. AS FOR TEMPS... WITH CLOUDS AND MODERATE CYCLONIC FLOW WOULD
EXPECT ANOTHER DAY OF LITTLE RISE ON TEMPS... WITH HIGHS RANGING FROM
MID 20S TO AROUND 30F.
TONIGHT... FLURRIES TO WANE EARLY FOLLOWED BY DECREASING CLOUDS
WITH SUBSIDENCE BUILDING IN WAKE OF DEPARTING SHORTWAVE. ENOUGH
WIND FROM NW AT 5-10 MPH SHOULD PREVENT BOTTOMING OUT ON TEMPS...
BUT WITH PARTIAL CLEARING EXPECT COLDER LOWS WITH WIDESPREAD
MID/UPPER TEENS. WIND CHILLS ONCE AGAIN DOWN IN THE SINGLE DIGITS.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 345 AM CST THU NOV 13 2014
OVERVIEW...A HIGHLY AMPLIFIED UPPER LEVEL PATTERN WITH A RIDGE
OVER THE E PACIFIC AND ALASKA AND A TROUGH OVER CENTRAL
CANADA/U.S. WILL CONTINUE TO BE REINFORCED THROUGH MID NEXT WEEK
AS A SERIES OF UPPER LEVEL DISTURBANCES DIVE SOUTHWARD FROM THE
CANADIAN ARCHIPELAGO INTO THE LOWER 48.
FRIDAY...AS A NOTABLE UPPER LEVEL LOW MOVES EASTWARD INTO QUEBEC...A
LOW-LEVEL SFC-850 MB RIDGE AXIS WILL BUILD INTO THE FORECAST AREA
WHICH WILL RESULT IN DECREASING WINDS AND DRY CONDITIONS.
HOWEVER...TEMPS WILL REMAIN WELL BELOW SEASONAL AVERAGES...REACHING
THE MID 20S TO LOWER 30S. THESE NUMBERS ARE CORROBORATED BY 1000-500
MB THICKNESSES NEAR 522 DAM. SREF HAS 850 MB TEMPS "WARMING" TO NEAR
-11 C BY THE EVENING.
SATURDAY WILL BE THE WARMEST DAY UNTIL WED OR THU OF NEXT WEEK.
HIGHS WILL BE IN THE LOWER TO MIDDLE 30S AHEAD OF A POSITIVELY
TILTED TROUGH DIVING SOUTHWARD INTO THE WESTERN U.S. THE WARMER
TEMPS SIGNAL INCREASING MOISTURE AND A GOOD CHANCE FOR PRECIP.
THE NAM/GFS/ECMWF SHOW AN AREA OF PACIFIC MOISTURE TRAVERSING THE
FOUR CORNERS REGION ON FRI WHICH IS THEN ADVECTED OUT AHEAD OF THE
AFOREMENTIONED TROUGH. FORCING FOR ASCENT IS TIED TO A LOW TO
MID-LEVEL WAA/PRESSURE ADVECTION REGIME AND UPPER DIVERGENCE IN
THE RIGHT ENTRANCE REGION OF A 300 MB JET STREAK. NEGATIVE OMEGA IS
MOST PROMINENT SAT EVENING BUT IS NOT OVERLY IMPRESSIVE.
THE NAM/ECMWF ARE MORE AGGRESSIVE WITH THE NORTHWARD MOISTURE
TRANSPORT AND PAINT AROUND 0.15 INCHES OF QPF WHILE THE GFS IS NEAR
OR SLIGHTLY BELOW 0.10 INCHES. THE NAM IS DRY THROUGH SAT AFTN BUT
IS AN OUTLIER IN THIS REGARD. 850 MB TEMPS AT -10 C SUPPORT ALL
SNOW...EVEN IF SFC TEMPS BRIEFLY WARM ABOVE FREEZING AT
MIDDAY...EVAPORATE COOLING WILL KNOCK TEMPS TO FREEZING OR BELOW
QUICKLY.
SNOW RATIOS WILL BE HIGH FOR THIS TIME OF YEAR. THE DGZ DEPTH WILL
BE IN THE 100-150 MB RANGE DURING THE CORE OF THE EVENT AND WILL BE
DEEPEST OVER THE NORTHERN CWA. THE DGZ DEPTH WILL INCREASE TO >200
MB AFTER 06Z/SUNDAY BUT MUCH OF THE SNOW WILL HAVE FALLEN BY THIS
TIME. ADDITIONALLY...SURFACE WINDS WILL BE LIGHT...SO NAM COBB SNOW
RATIOS AVERAGING NEAR NEAR 16:1 ARE REASONABLE. IF MODELS STAY ON
TRACK AVG SNOW AMOUNTS BETWEEN 1 TO 2 INCHES COULD BE EXPECTED
ACROSS THE CWA BY LATE SAT NIGHT WITH ISOLATED 3 INCH AMOUNTS
POSSIBLE.
SUNDAY INTO MIDDLE OF NEXT WEEK...HARD TO BELIEVE IT IS ONLY MID
NOVEMBER BUT COLDER AIR IS POISED TO ARRIVE DURING THIS TIME. MODELS
IN AGREEMENT BRINGING ANOTHER SURGE OF ARCTIC AIR INTO THE MIDWEST.
ANOTHER JET STREAK AND ATTENDANT VORTICITY MAX WILL ORIGINATE OVER
THE ARCTIC OCEAN AND PROPAGATE STRAIGHT TO THE SOUTH THROUGH CENTRAL
CANADA INTO THE CENTRAL U.S. IF IT WERE JANUARY THIS TYPE OF AIR MASS
TRAJECTORY COULD RESULT IN SOME BRUTALLY COLD TEMPS. CONSENSUS HAS
HIGHS IN THE LOW TO MID 20S ON MON/TUE BUT THIS MAY TREND SLIGHTLY
COLDER. 850 TEMPS NEAR -20 C WOULD BE 3 STANDARD DEVIATIONS BELOW
NORMAL AND WOULD BE A RECORD IN THE DVN SOUNDING CLIMATE DATA. LOWS
IN THE SINGLE DIGITS FOR SEVERAL CONSECUTIVE NIGHTS ARE A REAL
POSSIBILITY ALONG WITH SUB-ZERO WIND CHILLS ESPECIALLY NW OF
DAVENPORT. DRY WEATHER IS FORECAST DURING THIS TIME. TEMPS TRY TO
PUSH UP INTO THE LOWER TO MIDDLE BY WED AS 1000-500 MB THICKNESSES
RISE TO NEAR 534 DAM.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1123 AM CST THU NOV 13 2014
CONDITIONS WILL BE MAINLY MVFR THROUGH 03Z/14 WITH POCKETS OF VFR.
BRIEF IFR CONDITIONS ARE LIKELY IN SNOW SHOWERS THAT AFFECT A TAF
SITE AND MAY DROP VSBYS BRIEFLY DOWN TO 1SM. AFT 03Z/14 CONDITIONS
WILL SLOWLY IMPROVE TO VFR AS HIGH PRESSURE BUILDS INTO THE
MIDWEST.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...08
SYNOPSIS...MCCLURE
SHORT TERM...MCCLURE
LONG TERM...UTTECH
AVIATION...08
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1021 AM CST THU NOV 13 2014
.UPDATE...
ISSUED AT 1016 AM CST THU NOV 13 2014
A SIGNIFICANT REVISION HAS BEEN MADE TO THE FORECAST.
RADAR HAS FLURRIES AND SNOW SHOWERS ACROSS THE AREA IN ADVANCE OF
THE APPROACHING UPPER LEVEL DISTURBANCE. FORCING AND LIMITED
DAYTIME HEATING HAS CREATED NEW CLOUDS WITH AN INCREASE IN
COVERAGE OF THE FLURRIES AND SNOW SHOWERS.
IF TRENDS WITH THE RAP MODEL ARE CORRECT...SOME OF THE SNOW
SHOWERS SHOULD GET FAIRLY STRONG LATE THIS MORNING AND EARLY
AFTERNOON WITH THE POTENTIAL FOR MINOR ACCUMULATIONS IN SOME
LOCATIONS.
&&
.SYNOPSIS...
ISSUED AT 345 AM CST THU NOV 13 2014
LOWER CLOUDS HAVE ENVELOPED MUCH OF CWA FROM NORTH TO SOUTH WITH
APPROACH OF SHEARING UPPER LEVEL WAVE. OCCASIONAL FLURRIES ALSO
CONTINUE WITH SOME LIGHT SNOW SHOWERS PORTIONS OF SOUTHERN MN INTO
NORTHERN IA BRIEFLY REDUCING VSBYS TO AROUND 2-5SM. SFC ANALYSIS
SHOWS IMPRESSIVE AND ANOMALOUSLY STRONG ANTICYCLONE OF 1045+ MB
OVER PORTIONS OF NORTHERN ROCKIES... WITH COUPLE OF WEAK TROUGHS
OR WINDSHIFTS NOTED UPSTREAM ATTENDANT TO UPPER LEVEL DISTURBANCES
BEING SHUTTLED DOWN IN CYCLONIC FLOW. ITS STILL COLD... WITH
00Z DVN RAOB 850 TEMP OF -16.1C 3RD COLDEST 850 MB TEMP IN MONTH
OF NOVEMBER AT DVN... TIED WITH 2000 (11/21 00Z) AND 2005 (11/25
00Z)... WITH THE COLDEST BEING -16.8C IN 1997 (11/16 12Z).
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 345 AM CST THU NOV 13 2014
LOWER CLOUDS TO CONTINUE SAGGING SOUTHWARD THROUGH CWA AS SHEARING
UPPER LEVEL WAVE PASSES... AND MAY SEE SOME BREAKS FOR A TIME
THIS AM NORTH HALF... BUT SHOULD BE SHORT-LIVED WITH ANY DIURNAL
HEATING LENDING TO MORE LOW CLOUD DEVELOPMENT. THUS... CONTINUED
PT-MOCLDY SKIES ALONG WITH OCCASIONAL FLURRIES TDY. MAY SEE SOME
LIGHT SNOW SHOWERS DEVELOP BY MID-LATE AM THROUGH AFTN WITH APPROACH
OF SECONDARY SHORTWAVE CURRENTLY OVER NORTHERN WI... AND ALSO WITH
BUFR SOUNDINGS SHOWING STEEP LOW LEVEL LAPSE RATES EXTENDING UP
THROUGH THE DENDRITIC GROWTH ZONE FOR BRIEF REDUCED VSBYS WITH DUSTING
OR SO OF ACCUM POSSIBLE. AS MENTIONED EARLIER... ALREADY SEEING
VSBYS DROP DOWN IN RANGE OF 2-5SM OVER PORTIONS OF SOUTHERN MN EARLY
THIS AM. AS FOR TEMPS... WITH CLOUDS AND MODERATE CYCLONIC FLOW WOULD
EXPECT ANOTHER DAY OF LITTLE RISE ON TEMPS... WITH HIGHS RANGING FROM
MID 20S TO AROUND 30F.
TONIGHT... FLURRIES TO WANE EARLY FOLLOWED BY DECREASING CLOUDS
WITH SUBSIDENCE BUILDING IN WAKE OF DEPARTING SHORTWAVE. ENOUGH
WIND FROM NW AT 5-10 MPH SHOULD PREVENT BOTTOMING OUT ON TEMPS...
BUT WITH PARTIAL CLEARING EXPECT COLDER LOWS WITH WIDESPREAD
MID/UPPER TEENS. WIND CHILLS ONCE AGAIN DOWN IN THE SINGLE DIGITS.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 345 AM CST THU NOV 13 2014
OVERVIEW...A HIGHLY AMPLIFIED UPPER LEVEL PATTERN WITH A RIDGE
OVER THE E PACIFIC AND ALASKA AND A TROUGH OVER CENTRAL
CANADA/U.S. WILL CONTINUE TO BE REINFORCED THROUGH MID NEXT WEEK
AS A SERIES OF UPPER LEVEL DISTURBANCES DIVE SOUTHWARD FROM THE
CANADIAN ARCHIPELAGO INTO THE LOWER 48.
FRIDAY...AS A NOTABLE UPPER LEVEL LOW MOVES EASTWARD INTO QUEBEC...A
LOW-LEVEL SFC-850 MB RIDGE AXIS WILL BUILD INTO THE FORECAST AREA
WHICH WILL RESULT IN DECREASING WINDS AND DRY CONDITIONS.
HOWEVER...TEMPS WILL REMAIN WELL BELOW SEASONAL AVERAGES...REACHING
THE MID 20S TO LOWER 30S. THESE NUMBERS ARE CORROBORATED BY 1000-500
MB THICKNESSES NEAR 522 DAM. SREF HAS 850 MB TEMPS "WARMING" TO NEAR
-11 C BY THE EVENING.
SATURDAY WILL BE THE WARMEST DAY UNTIL WED OR THU OF NEXT WEEK.
HIGHS WILL BE IN THE LOWER TO MIDDLE 30S AHEAD OF A POSITIVELY
TILTED TROUGH DIVING SOUTHWARD INTO THE WESTERN U.S. THE WARMER
TEMPS SIGNAL INCREASING MOISTURE AND A GOOD CHANCE FOR PRECIP.
THE NAM/GFS/ECMWF SHOW AN AREA OF PACIFIC MOISTURE TRAVERSING THE
FOUR CORNERS REGION ON FRI WHICH IS THEN ADVECTED OUT AHEAD OF THE
AFOREMENTIONED TROUGH. FORCING FOR ASCENT IS TIED TO A LOW TO
MID-LEVEL WAA/PRESSURE ADVECTION REGIME AND UPPER DIVERGENCE IN
THE RIGHT ENTRANCE REGION OF A 300 MB JET STREAK. NEGATIVE OMEGA IS
MOST PROMINENT SAT EVENING BUT IS NOT OVERLY IMPRESSIVE.
THE NAM/ECMWF ARE MORE AGGRESSIVE WITH THE NORTHWARD MOISTURE
TRANSPORT AND PAINT AROUND 0.15 INCHES OF QPF WHILE THE GFS IS NEAR
OR SLIGHTLY BELOW 0.10 INCHES. THE NAM IS DRY THROUGH SAT AFTN BUT
IS AN OUTLIER IN THIS REGARD. 850 MB TEMPS AT -10 C SUPPORT ALL
SNOW...EVEN IF SFC TEMPS BRIEFLY WARM ABOVE FREEZING AT
MIDDAY...EVAPORATE COOLING WILL KNOCK TEMPS TO FREEZING OR BELOW
QUICKLY.
SNOW RATIOS WILL BE HIGH FOR THIS TIME OF YEAR. THE DGZ DEPTH WILL
BE IN THE 100-150 MB RANGE DURING THE CORE OF THE EVENT AND WILL BE
DEEPEST OVER THE NORTHERN CWA. THE DGZ DEPTH WILL INCREASE TO >200
MB AFTER 06Z/SUNDAY BUT MUCH OF THE SNOW WILL HAVE FALLEN BY THIS
TIME. ADDITIONALLY...SURFACE WINDS WILL BE LIGHT...SO NAM COBB SNOW
RATIOS AVERAGING NEAR NEAR 16:1 ARE REASONABLE. IF MODELS STAY ON
TRACK AVG SNOW AMOUNTS BETWEEN 1 TO 2 INCHES COULD BE EXPECTED
ACROSS THE CWA BY LATE SAT NIGHT WITH ISOLATED 3 INCH AMOUNTS
POSSIBLE.
SUNDAY INTO MIDDLE OF NEXT WEEK...HARD TO BELIEVE IT IS ONLY MID
NOVEMBER BUT COLDER AIR IS POISED TO ARRIVE DURING THIS TIME. MODELS
IN AGREEMENT BRINGING ANOTHER SURGE OF ARCTIC AIR INTO THE MIDWEST.
ANOTHER JET STREAK AND ATTENDANT VORTICITY MAX WILL ORIGINATE OVER
THE ARCTIC OCEAN AND PROPAGATE STRAIGHT TO THE SOUTH THROUGH CENTRAL
CANADA INTO THE CENTRAL U.S. IF IT WERE JANUARY THIS TYPE OF AIRMASS
TRAJECTORY COULD RESULT IN SOME BRUTALLY COLD TEMPS. CONSENSUS HAS
HIGHS IN THE LOW TO MID 20S ON MON/TUE BUT THIS MAY TREND SLIGHTLY
COLDER. 850 TEMPS NEAR -20 C WOULD BE 3 STANDARD DEVIATIONS BELOW
NORMAL AND WOULD BE A RECORD IN THE DVN SOUNDING CLIMATE DATA. LOWS
IN THE SINGLE DIGITS FOR SEVERAL CONSECUTIVE NIGHTS ARE A REAL
POSSIBILITY ALONG WITH SUB-ZERO WIND CHILLS ESPECIALLY NW OF
DAVENPORT. DRY WEATHER IS FORECAST DURING THIS TIME. TEMPS TRY TO
PUSH UP INTO THE LOWER TO MIDDLE BY WED AS 1000-500 MB THICKNESSES
RISE TO NEAR 534 DAM.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1016 AM CST THU NOV 13 2014
SNOW SHOWERS ARE INCREASING IN COVERAGE ACROSS EASTERN IOWA AND
NORTHERN ILLINOIS. IF CURRENT TRENDS FROM THE RAP MODEL ARE
CORRECT...SOME OF THE SNOW SHOWERS MAY BE QUITE STRONG AND PRODUCE
A PERIOD OF IFR CONDITIONS. THIS HAS ALREADY OCCURRED AT KDBQ
WHICH LENDS SOME CREDENCE TO WHAT THE RAP MODEL IS SUGGESTING.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...08
SYNOPSIS...MCCLURE
SHORT TERM...MCCLURE
LONG TERM...UTTECH
AVIATION...08
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
559 AM CST THU NOV 13 2014
.SYNOPSIS...
ISSUED AT 345 AM CST THU NOV 13 2014
LOWER CLOUDS HAVE ENVELOPED MUCH OF CWA FROM NORTH TO SOUTH WITH
APPROACH OF SHEARING UPPER LEVEL WAVE. OCCASIONAL FLURRIES ALSO
CONTINUE WITH SOME LIGHT SNOW SHOWERS PORTIONS OF SOUTHERN MN INTO
NORTHERN IA BRIEFLY REDUCING VSBYS TO AROUND 2-5SM. SFC ANALYSIS
SHOWS IMPRESSIVE AND ANOMALOUSLY STRONG ANTICYCLONE OF 1045+ MB
OVER PORTIONS OF NORTHERN ROCKIES... WITH COUPLE OF WEAK TROUGHS
OR WINDSHIFTS NOTED UPSTREAM ATTENDANT TO UPPER LEVEL DISTURBANCES
BEING SHUTTLED DOWN IN CYCLONIC FLOW. ITS STILL COLD... WITH
00Z DVN RAOB 850 TEMP OF -16.1C 3RD COLDEST 850 MB TEMP IN MONTH
OF NOVEMBER AT DVN... TIED WITH 2000 (11/21 00Z) AND 2005 (11/25
00Z)... WITH THE COLDEST BEING -16.8C IN 1997 (11/16 12Z).
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 345 AM CST THU NOV 13 2014
LOWER CLOUDS TO CONTINUE SAGGING SOUTHWARD THROUGH CWA AS SHEARING
UPPER LEVEL WAVE PASSES... AND MAY SEE SOME BREAKS FOR A TIME
THIS AM NORTH HALF... BUT SHOULD BE SHORT-LIVED WITH ANY DIURNAL
HEATING LENDING TO MORE LOW CLOUD DEVELOPMENT. THUS... CONTINUED
PT-MOCLDY SKIES ALONG WITH OCCASIONAL FLURRIES TDY. MAY SEE SOME
LIGHT SNOW SHOWERS DEVELOP BY MID-LATE AM THROUGH AFTN WITH APPROACH
OF SECONDARY SHORTWAVE CURRENTLY OVER NORTHERN WI... AND ALSO WITH
BUFR SOUNDINGS SHOWING STEEP LOW LEVEL LAPSE RATES EXTENDING UP
THROUGH THE DENDRITIC GROWTH ZONE FOR BRIEF REDUCED VSBYS WITH DUSTING
OR SO OF ACCUM POSSIBLE. AS MENTIONED EARLIER... ALREADY SEEING
VSBYS DROP DOWN IN RANGE OF 2-5SM OVER PORTIONS OF SOUTHERN MN EARLY
THIS AM. AS FOR TEMPS... WITH CLOUDS AND MODERATE CYCLONIC FLOW WOULD
EXPECT ANOTHER DAY OF LITTLE RISE ON TEMPS... WITH HIGHS RANGING FROM
MID 20S TO AROUND 30F.
TONIGHT... FLURRIES TO WANE EARLY FOLLOWED BY DECREASING CLOUDS
WITH SUBSIDENCE BUILDING IN WAKE OF DEPARTING SHORTWAVE. ENOUGH
WIND FROM NW AT 5-10 MPH SHOULD PREVENT BOTTOMING OUT ON TEMPS...
BUT WITH PARTIAL CLEARING EXPECT COLDER LOWS WITH WIDESPREAD
MID/UPPER TEENS. WIND CHILLS ONCE AGAIN DOWN IN THE SINGLE DIGITS.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 345 AM CST THU NOV 13 2014
OVERVIEW...A HIGHLY AMPLIFIED UPPER LEVEL PATTERN WITH A RIDGE
OVER THE E PACIFIC AND ALASKA AND A TROUGH OVER CENTRAL
CANADA/U.S. WILL CONTINUE TO BE REINFORCED THROUGH MID NEXT WEEK
AS A SERIES OF UPPER LEVEL DISTURBANCES DIVE SOUTHWARD FROM THE
CANADIAN ARCHIPELAGO INTO THE LOWER 48.
FRIDAY...AS A NOTABLE UPPER LEVEL LOW MOVES EASTWARD INTO QUEBEC...A
LOW-LEVEL SFC-850 MB RIDGE AXIS WILL BUILD INTO THE FORECAST AREA
WHICH WILL RESULT IN DECREASING WINDS AND DRY CONDITIONS.
HOWEVER...TEMPS WILL REMAIN WELL BELOW SEASONAL AVERAGES...REACHING
THE MID 20S TO LOWER 30S. THESE NUMBERS ARE CORROBORATED BY 1000-500
MB THICKNESSES NEAR 522 DAM. SREF HAS 850 MB TEMPS "WARMING" TO NEAR
-11 C BY THE EVENING.
SATURDAY WILL BE THE WARMEST DAY UNTIL WED OR THU OF NEXT WEEK.
HIGHS WILL BE IN THE LOWER TO MIDDLE 30S AHEAD OF A POSITIVELY
TILTED TROUGH DIVING SOUTHWARD INTO THE WESTERN U.S. THE WARMER
TEMPS SIGNAL INCREASING MOISTURE AND A GOOD CHANCE FOR PRECIP.
THE NAM/GFS/ECMWF SHOW AN AREA OF PACIFIC MOISTURE TRAVERSING THE
FOUR CORNERS REGION ON FRI WHICH IS THEN ADVECTED OUT AHEAD OF THE
AFOREMENTIONED TROUGH. FORCING FOR ASCENT IS TIED TO A LOW TO
MID-LEVEL WAA/PRESSURE ADVECTION REGIME AND UPPER DIVERGENCE IN
THE RIGHT ENTRANCE REGION OF A 300 MB JET STREAK. NEGATIVE OMEGA IS
MOST PROMINENT SAT EVENING BUT IS NOT OVERLY IMPRESSIVE.
THE NAM/ECMWF ARE MORE AGGRESSIVE WITH THE NORTHWARD MOISTURE
TRANSPORT AND PAINT AROUND 0.15 INCHES OF QPF WHILE THE GFS IS NEAR
OR SLIGHTLY BELOW 0.10 INCHES. THE NAM IS DRY THROUGH SAT AFTN BUT
IS AN OUTLIER IN THIS REGARD. 850 MB TEMPS AT -10 C SUPPORT ALL
SNOW...EVEN IF SFC TEMPS BRIEFLY WARM ABOVE FREEZING AT
MIDDAY...EVAPORATE COOLING WILL KNOCK TEMPS TO FREEZING OR BELOW
QUICKLY.
SNOW RATIOS WILL BE HIGH FOR THIS TIME OF YEAR. THE DGZ DEPTH WILL
BE IN THE 100-150 MB RANGE DURING THE CORE OF THE EVENT AND WILL BE
DEEPEST OVER THE NORTHERN CWA. THE DGZ DEPTH WILL INCREASE TO >200
MB AFTER 06Z/SUNDAY BUT MUCH OF THE SNOW WILL HAVE FALLEN BY THIS
TIME. ADDITIONALLY...SURFACE WINDS WILL BE LIGHT...SO NAM COBB SNOW
RATIOS AVERAGING NEAR NEAR 16:1 ARE REASONABLE. IF MODELS STAY ON
TRACK AVG SNOW AMOUNTS BETWEEN 1 TO 2 INCHES COULD BE EXPECTED
ACROSS THE CWA BY LATE SAT NIGHT WITH ISOLATED 3 INCH AMOUNTS
POSSIBLE.
SUNDAY INTO MIDDLE OF NEXT WEEK...HARD TO BELIEVE IT IS ONLY MID
NOVEMBER BUT COLDER AIR IS POISED TO ARRIVE DURING THIS TIME. MODELS
IN AGREEMENT BRINGING ANOTHER SURGE OF ARCTIC AIR INTO THE MIDWEST.
ANOTHER JET STREAK AND ATTENDANT VORTICITY MAX WILL ORIGINATE OVER
THE ARCTIC OCEAN AND PROPAGATE STRAIGHT TO THE SOUTH THROUGH CENTRAL
CANADA INTO THE CENTRAL U.S. IF IT WERE JANUARY THIS TYPE OF AIRMASS
TRAJECTORY COULD RESULT IN SOME BRUTALLY COLD TEMPS. CONSENSUS HAS
HIGHS IN THE LOW TO MID 20S ON MON/TUE BUT THIS MAY TREND SLIGHTLY
COLDER. 850 TEMPS NEAR -20 C WOULD BE 3 STANDARD DEVIATIONS BELOW
NORMAL AND WOULD BE A RECORD IN THE DVN SOUNDING CLIMATE DATA. LOWS
IN THE SINGLE DIGITS FOR SEVERAL CONSECUTIVE NIGHTS ARE A REAL
POSSIBILITY ALONG WITH SUB-ZERO WIND CHILLS ESPECIALLY NW OF
DAVENPORT. DRY WEATHER IS FORECAST DURING THIS TIME. TEMPS TRY TO
PUSH UP INTO THE LOWER TO MIDDLE BY WED AS 1000-500 MB THICKNESSES
RISE TO NEAR 534 DAM.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 549 AM CST THU NOV 13 2014
STRATUS WITH MVFR TO LOWER VFR CIGS AND OCCASIONAL FLURRIES AND
NORTHWEST WINDS AROUND 10-15 KTS EXPECTED TODAY. WITH AN
APPROACHING UPPER LEVEL DISTURBANCE THERE MAY ALSO BE SOME SNOW
SHOWERS AROUND FROM MID AM THROUGH AFTN... WHICH COULD DROP VSBYS
IN RANGE OF AROUND 2-5SM FOR BRIEF PERIODS OF TIME RESULTING IN A
DUSTING OF ACCUM. NOT CONFIDENT ON IMPACT AT TERMINAL ATTIM THUS
LEFT OUT MENTION. RAP MODEL MOST AGGRESSIVE WITH DEPICTING LOW MVFR
STRATUS HANGING ON MUCH OF TONIGHT... AND FOR NOW SIDED TOWARD MORE
OPTIMISTIC CONSENSUS AS ANTICIPATE SUBSIDENCE IN WAKE OF DEPARTING
DISTURBANCE MAY AID IN PARTIAL CLEARING WITH ANY CIGS LIFTING TO
VFR. NORTHWEST WINDS EXPECTED IN GENERAL RANGE OF 5-9 KTS TONIGHT.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
SYNOPSIS...MCCLURE
SHORT TERM...MCCLURE
LONG TERM...UTTECH
AVIATION...05
AREA FORECAST DISCUSSION
NWS GOODLAND KS
400 PM MST THU NOV 13 2014
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 126 PM MST THU NOV 13 2014
DECENT REBOUND IN AREA TEMPERATURES OFF OF THE MORNING LOWS...AS THE
FORECAST AREA CURRENTLY SITS IN THE UPPER TEENS THROUGH THE MID
20S...UNDER MSUNNY/SUNNY SKIES. RIDGE AXIS CONTINUES TO PUSH SLOWLY
EASTWARD FURTHER ON INTO THE CENTRAL PLAINS...ALLOWING FOR WEAK
RETURN/SOUTHERLY FLOW TO WORK INTO WESTERN PORTIONS OF THE FORECAST
AREA. THE CLOUD COVER ASSOCIATED WITH THE SYSTEM MOVING THRU THE
ROCKIES WILL CONTINUE TO PUSH NORTH AND EAST ACROSS THE TRI STATE
REGION OVERNIGHT...WITH THE ENTIRE AREA UNDER SOUTHERLY WIND REGIME.
INITIALLY LOOKING FOR MID/HIGH CLOUDS TO SHIFT OVER AREA...BUT AFTER
MIDNIGHT TONIGHT LOW LEVEL CLOUDS THAT HAVE BEEN SITTING OFF TO OUR
SOUTH AND EAST WILL WORK NORTHWARD.
FOCUS FOR ANY FLURRIES OR WEAK --SW WILL OCCUR MAINLY OVER EASTERN
COLORADO WHERE TEMP/PRESSURE CONFLUENCE IS OCCURRING BETWEEN
APPROACHING SYSTEM AND STRONG RIDGE TO THE EAST OF THE CWA. THIS IS
CURRENTLY OVER CENTRAL COLORADO AND WILL SHIFT EAST OVERNIGHT. NO
MAJOR ACCUMULATION IS EXPECTED WITH AFFECTED AREA SEEING A TRACE TO
ONLY A FEW TENTHS OF AN INCH. FOR TEMPS/WIND CHILL CONCERNS
OVERNIGHT...NOT PLANNING ON ANY PRODUCT ISSUANCE AT THIS TIME AS
WITH SOUTHERLY FLOW REMAINING INTACT OVERNIGHT AND INCREASING CLOUD
COVER EXPECTED. TEMPS ARE EXPECTED TO FALL INTO/CLOSE TO THE SINGLE
NUMBERS UNTIL THICKER LOW LEVEL CLOUDS ARRIVE THEN SHOULD HOLD
STEADY OR SLOWLY INCREASE FROM THERE. OVERALL LOWS FOR TONIGHT WILL
RANGE IN THE SINGLE NUMBERS ABOVE ZERO...WARMEST IN EASTERN ZONES.
GOING INTO FRIDAY...MUCH OF THE CWA WILL REMAIN UNDER PARTLY SUNNY
CONDITIONS...WITH RIDGE TO THE EAST AND AREA UNDER SOUTHERLY FLOW
AROUND 10-20 MPH. EXPECTED CLOUD COVER WILL HAMPER DAYTIME HIGHS
DESPITE WINDS...SO HAVE UNDERCUT MODEL GUIDANCE GIVING THE AREA A
RANGE IN THE MID TO UPPER 20S FOR HIGH TEMPERATURES. POSSIBILITY FOR
SOME BRIEF MORNING FLURRIES OR SNOW SHOWERS ACROSS NW ZONES
OTHERWISE LOOKING FOR NO OTHER WEATHER TO AFFECT THE AREA DURING THE
DAY.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 136 PM MST THU NOV 13 2014
AN UPPER LEVEL SHORT WAVE TROUGH EMBEDDED IN THE JET IN PLACE
ACROSS THE SOUTHERN UNITED STATES TRAVERSES THE SOUTHWEST UNITED
STATES ON FRIDAY AND MOVES EAST OF THE ROCKIES AND ACROSS THE
SOUTHERN AND CENTRAL HIGH PLAINS EARLY SATURDAY. THIS WILL SPREAD
AN AREA OF LIGHT SNOW ACROSS MAINLY THE SOUTHERN AND EASTERN
SECTIONS OF THE FORECAST AREA FRIDAY NIGHT AND SATURDAY MORNING.
THE UPPER SHORT WAVE TROUGH EXITS TO THE EAST OUT OF THE REGION
WITH THE NEXT STRONGER UPPER TROUGH DIVING SOUTH THROUGH THE
WESTERN UNITED STATES. THIS STRONGER TROUGH MOVES THROUGH THE
CENTRAL HIGH PLAINS REGION SATURDAY NIGHT AND EARLY SUNDAY WITH AN
AREA OF SUBSIDENCE MOVING ACROSS THE FORECAST AREA BY SUNDAY
AFTERNOON. THIS WILL SPREAD ANOTHER AREA OF LIGHT SNOW SOUTHWARD
ACROSS MAINLY THE WESTERN PORTIONS OF THE FORECAST AREA LATE
SATURDAY THROUGH SATURDAY NIGHT THAT WILL END QUICKLY EARLY SUNDAY.
TOTAL SNOWFALL AMOUNTS FROM THE TWO PERIOD OF LIGHT SNOW WILL
VARY FROM LESS THAN AN INCH ACROSS SOUTHWEST NEBRASKA TO NEARLY 3
INCHES OVER CENTRAL KANSAS. EASTERN COLORADO SHOULD SEE BETWEEN 1
AND 2 INCHES OF SNOW.
EXPECT TEMPERATURES TO COOL SATURDAY AND SATURDAY NIGHT AS THE
SURGE OF COLD AIR MOVES IN BEHIND A COLD FRONT. SHOULD SEE
TEMPERATURES RISING AGAIN ON SUNDAY AND THROUGH NEXT WEEK AS COLD
AIR STARTS MOVING OUT OF THE REGION. THE HIGH AMPLITUDE RIDGE OVER
THE WESTERN UNITED STATES IS EXPECTED TO FLATTEN AND MOVE EASTWARD
OVER THE ROCKIES AND THE CENTRAL HIGH PLAINS REGION BY MID-WEEK.
RESULTING CONDITIONS ARE EXPECTED TO BE DRY NEXT WEEK THROUGH THE
MIDDLE OF THE WEEK WITH DAYTIME HIGHS RETURNING TO THE 40S BY
WEDNESDAY AND THURSDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 400 PM MST THU NOV 13 2014
BATCH OF 850-500 MOISTURE FORECAST TO REACH THE KGLD TERMINAL FROM
THE WEST AROUND 03Z...EXITING IN THE 06Z-07Z TIMEFRAME. FOR KMCK
IT ARRIVES AROUND 07Z AND EXITS TO THE NORTHEAST AROUND 10Z. LEFT
FRONT QUAD OF UPPER JET HEADS FROM THE FOUR CORNERS AREA AT TAF
ISSUANCE TO THE OKLAHOMA PANHANDLE BY 12Z FRIDAY. THERE SHOULD BE
SOME SUPPORT FROM THE JET AND A BIT OF MID LEVEL FORCING TO
PRODUCE SOME FLURRIES AS THE DISTURBANCE MOVES THROUGH. FOR NOW
WILL LEAVE FLURRIES OUT AS THEY ARENT EXPECTED TO CREATE AN
AVIATION HAZARD OR BRING TERMINALS TO MVFR CATEGORIES. FRIDAY...FOR
KGLD WE SHOULD BE IN BETWEEN SYSTEMS THUS A MOSTLY SUNNY SKY. FOR
KMCK THERE IS ENOUGH LINGERING LOW LEVEL MOISTURE TO PRODUCE A BKN
DECK OF CLOUDS AROUND/JUST ABOVE MVFR RANGE.
AM CONCERNED ABOUT MVFR CLOUDS CURRENTLY ALONG THE FRONT RANGE AND
ALONG/SOUTH OF THE PALMER DIVIDE PER OBS AND RUC 75+ PERCENT RH
REACHING THE KGLD TERMINAL IN THE 03Z-09Z TIMEFRAME. HAVE DEBATED
WHETHER OR NOT INCLUDE MVFR CIGS AND FOR NOW HAVE KEPT THEM OUT OF
THE TAF BUT WILL WATCH CLOSELY.
OTHERWISE...SOUTH WINDS AROUND 10KTS AT KGLD AT TAF ISSUANCE
CONTINUE THROUGH 14Z THEN INCREASE AND GUST IN THE 20-25KT RANGE
IN THE 17Z-22Z TIMEFRAME. FOR KMCK LGT/VRB WINDS AT TAF ISSUANCE
BECOME SOUTHEASTERLY AROUND 07KTS AT 10Z THEN VEER TO THE SOUTH
AND GUST 15-20KTS FROM 17Z-22Z.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...JN
LONG TERM...LOCKHART
AVIATION...99
AREA FORECAST DISCUSSION
NWS PADUCAH KY
1135 AM CST Thu Nov 13 2014
.UPDATE...
Issued at 1135 CST THU NOV 13 2014
Updated for aviation forecast discussion.
.SHORT TERM...(Today through Saturday)
Issued at 350 AM CST THU NOV 13 2014
A near term challenge is forecasting the coverage of clouds, which
have been a broken mix of low, mid, and high variety overnight. It
looks like the RAP model may have the best handle on the overall
pattern of cloudiness, if not necessarily the coverage (which
appeared a bit lacking in the model). The diminishing of most
cloudiness should be underway across the wrn two thirds of the PAH
forecast area by midday, with a possible resurgence in the I-64
corridor during the afternoon. It appears that the clearing pattern
is generally associated with a 700 mb trof axis which is forecast to
move ewd through the cyclonic pattern aloft. After today, opaque
cloud cover should be minimal.
An arctic air mass will continue to filter into the region through
Fri night, before easing off to the east on Sat. The mid/upper
pattern will take on brief ridging ahead of the next system. Low
level flow should have enough time to turn to the south by Sat
afternoon, giving a limited boost to temps. Measurable pcpn is
possible in the afternoon, first rainfall, then perhaps some
snowfall in the nwrn half of our region toward evening as the lower
trop cools. The area with the best chance of measuring more than a
tenth of an inch of snow will be the higher elevations of the Ozark
Foothills. Temps much below average will continue in the short term
period.
.LONG TERM...(Saturday night through Wednesday)
Issued at 350 AM CST THU NOV 13 2014
Low to medium forecast confidence in the long term with models still
not in good agreement.
Overrunning precipitation due to isentropic upglide should be
underway at the beginning of the long term period. Thermal profiles
still indicating all precipitation to be snow, but models still
quite different on QPF amounts. Models do however indicate the best
chances for snow Saturday night should be over the northwest half of
the CWA. The latest GFS run still the colder of the extended models.
A cold front is still expected to blast across the CWA on Sunday.
For Sunday morning, thermal profiles would suggest a rain/snow/sleet
mix over the southeast third of our CWA with snow elsewhere. For
Sunday afternoon models are indicating the lower levels warming up a
bit, so expect snow over the northwest third, a rain/snow/sleet mix
over the middle third, with all rain over the southeast third.
Sunday evening, in the wake of the frontal passage, the combination
of the approach of a short wave, an inverted trough over the deep
south, and plenty of moisture will induce a deformation zone and
produce yet another overrunning precipitation scenario but with more
impressive QPF amounts than Saturday night. As the cooler
post-frontal air overspreads the region Sunday evening, expect a
snow/sleet mix over the southeast third of the CWA, with all snow
elsewhere.
After midnight Sunday night precipitation should change over to all
snow. Snow may linger over the far southeast portions of our CWA
Monday morning, but little to no additional snow accumulation is
expected. Total snow accumulation from Saturday night through Sunday
night should max out somewhere in the 1.5-2.0 inch range area-wide,
with the majority falling Sunday night.
Beyond that, high pressure at the surface and flow aloft becoming
more northwest should produce dry conditions through the remainder
of the long term period along with below normal temperatures.
&&
.AVIATION...
Issued at 1135 AM CST THU NOV 13 2014
As an arctic air mass continues to filter into the region, substantial
cloud cover will probably linger for most of the daylight hours
and low level moisture is abundant. Latest satellite shows a decent
looking strato-cu deck heading southeast into the region. Not sure
how long this low vfr deck will stick around past 00Z, but that
will have to be watched in addition to any lowering of ceilings
after dark. If any clouds do linger into the evening/overnight,
they should clear by morning as the main trough to our north
pushes east. North to nw sustained winds around 10-12 knots with
occasional higher gusts will prevail during the day before
decreasing overnight.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PADUCAH KY
957 AM CST Thu Nov 13 2014
.UPDATE...
Issued at 957 AM CST THU NOV 13 2014
KPAH/KEVV radar along with a few spotter reports have revealed a
few snow flurries/light snow showers occurring with this band of
clouds moving through the area this morning. According to radar,
it appears most of the echoes are over S. IL, SW IN and parts of
W. KY. Looking upstream, there are additional reports of
flurries in association with more clouds heading this way. So,
will add in some scattered flurries to the forecast grids for
several hours based on these trends. No accumulation expected.
.SHORT TERM...(Today through Saturday)
Issued at 350 AM CST THU NOV 13 2014
A near term challenge is forecasting the coverage of clouds, which
have been a broken mix of low, mid, and high variety overnight. It
looks like the RAP model may have the best handle on the overall
pattern of cloudiness, if not necessarily the coverage (which
appeared a bit lacking in the model). The diminishing of most
cloudiness should be underway across the wrn two thirds of the PAH
forecast area by midday, with a possible resurgence in the I-64
corridor during the afternoon. It appears that the clearing pattern
is generally associated with a 700 mb trof axis which is forecast to
move ewd through the cyclonic pattern aloft. After today, opaque
cloud cover should be minimal.
An arctic air mass will continue to filter into the region through
Fri night, before easing off to the east on Sat. The mid/upper
pattern will take on brief ridging ahead of the next system. Low
level flow should have enough time to turn to the south by Sat
afternoon, giving a limited boost to temps. Measurable pcpn is
possible in the afternoon, first rainfall, then perhaps some
snowfall in the nwrn half of our region toward evening as the lower
trop cools. The area with the best chance of measuring more than a
tenth of an inch of snow will be the higher elevations of the Ozark
Foothills. Temps much below average will continue in the short term
period.
.LONG TERM...(Saturday night through Wednesday)
Issued at 350 AM CST THU NOV 13 2014
Low to medium forecast confidence in the long term with models still
not in good agreement.
Overrunning precipitation due to isentropic upglide should be
underway at the beginning of the long term period. Thermal profiles
still indicating all precipitation to be snow, but models still
quite different on QPF amounts. Models do however indicate the best
chances for snow Saturday night should be over the northwest half of
the CWA. The latest GFS run still the colder of the extended models.
A cold front is still expected to blast across the CWA on Sunday.
For Sunday morning, thermal profiles would suggest a rain/snow/sleet
mix over the southeast third of our CWA with snow elsewhere. For
Sunday afternoon models are indicating the lower levels warming up a
bit, so expect snow over the northwest third, a rain/snow/sleet mix
over the middle third, with all rain over the southeast third.
Sunday evening, in the wake of the frontal passage, the combination
of the approach of a short wave, an inverted trough over the deep
south, and plenty of moisture will induce a deformation zone and
produce yet another overrunning precipitation scenario but with more
impressive QPF amounts than Saturday night. As the cooler
post-frontal air overspreads the region Sunday evening, expect a
snow/sleet mix over the southeast third of the CWA, with all snow
elsewhere.
After midnight Sunday night precipitation should change over to all
snow. Snow may linger over the far southeast portions of our CWA
Monday morning, but little to no additional snow accumulation is
expected. Total snow accumulation from Saturday night through Sunday
night should max out somewhere in the 1.5-2.0 inch range area-wide,
with the majority falling Sunday night.
Beyond that, high pressure at the surface and flow aloft becoming
more northwest should produce dry conditions through the remainder
of the long term period along with below normal temperatures.
&&
.AVIATION...
Issued at 619 AM CST THU NOV 13 2014
As an arctic air mass continues to filter into the region, VFR cigs
are forecast to lift this morning, but substantial cloud cover will
probably linger for most of the daylight hours in the ern third of
the region. North to nw sustained winds around 10-12 knots will
prevail during the day before decreasing overnight.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
UPDATE...CW
SHORT TERM...DB
LONG TERM...JP
AVIATION...DB
AREA FORECAST DISCUSSION
NWS PADUCAH KY
619 AM CST Thu Nov 13 2014
.UPDATE...
Issued at 619 AM CST THU NOV 13 2014
Updated aviation discussion only.
.SHORT TERM...(Today through Saturday)
Issued at 350 AM CST THU NOV 13 2014
A near term challenge is forecasting the coverage of clouds, which
have been a broken mix of low, mid, and high variety overnight. It
looks like the RAP model may have the best handle on the overall
pattern of cloudiness, if not necessarily the coverage (which
appeared a bit lacking in the model). The diminishing of most
cloudiness should be underway across the wrn two thirds of the PAH
forecast area by midday, with a possible resurgence in the I-64
corridor during the afternoon. It appears that the clearing pattern
is generally associated with a 700 mb trof axis which is forecast to
move ewd through the cyclonic pattern aloft. After today, opaque
cloud cover should be minimal.
An arctic air mass will continue to filter into the region through
Fri night, before easing off to the east on Sat. The mid/upper
pattern will take on brief ridging ahead of the next system. Low
level flow should have enough time to turn to the south by Sat
afternoon, giving a limited boost to temps. Measurable pcpn is
possible in the afternoon, first rainfall, then perhaps some
snowfall in the nwrn half of our region toward evening as the lower
trop cools. The area with the best chance of measuring more than a
tenth of an inch of snow will be the higher elevations of the Ozark
Foothills. Temps much below average will continue in the short term
period.
.LONG TERM...(Saturday night through Wednesday)
Issued at 350 AM CST THU NOV 13 2014
Low to medium forecast confidence in the long term with models still
not in good agreement.
Overrunning precipitation due to isentropic upglide should be
underway at the beginning of the long term period. Thermal profiles
still indicating all precipitation to be snow, but models still
quite different on QPF amounts. Models do however indicate the best
chances for snow Saturday night should be over the northwest half of
the CWA. The latest GFS run still the colder of the extended models.
A cold front is still expected to blast across the CWA on Sunday.
For Sunday morning, thermal profiles would suggest a rain/snow/sleet
mix over the southeast third of our CWA with snow elsewhere. For
Sunday afternoon models are indicating the lower levels warming up a
bit, so expect snow over the northwest third, a rain/snow/sleet mix
over the middle third, with all rain over the southeast third.
Sunday evening, in the wake of the frontal passage, the combination
of the approach of a short wave, an inverted trough over the deep
south, and plenty of moisture will induce a deformation zone and
produce yet another overrunning precipitation scenario but with more
impressive QPF amounts than Saturday night. As the cooler
post-frontal air overspreads the region Sunday evening, expect a
snow/sleet mix over the southeast third of the CWA, with all snow
elsewhere.
After midnight Sunday night precipitation should change over to all
snow. Snow may linger over the far southeast portions of our CWA
Monday morning, but little to no additional snow accumulation is
expected. Total snow accumulation from Saturday night through Sunday
night should max out somewhere in the 1.5-2.0 inch range area-wide,
with the majority falling Sunday night.
Beyond that, high pressure at the surface and flow aloft becoming
more northwest should produce dry conditions through the remainder
of the long term period along with below normal temperatures.
&&
.AVIATION...
Issued at 619 AM CST THU NOV 13 2014
As an arctic air mass continues to filter into the region, VFR cigs
are forecast to lift this morning, but substantial cloud cover will
probably linger for most of the daylight hours in the ern third of
the region. North to nw sustained winds around 10-12 knots will
prevail during the day before decreasing overnight.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
SHORT TERM...DB
LONG TERM...JP
AVIATION...DB
AREA FORECAST DISCUSSION
NWS PADUCAH KY
350 AM CST Thu Nov 13 2014
.SHORT TERM...(Today through Saturday)
Issued at 350 AM CST THU NOV 13 2014
A near term challenge is forecasting the coverage of clouds, which
have been a broken mix of low, mid, and high variety overnight. It
looks like the RAP model may have the best handle on the overall
pattern of cloudiness, if not necessarily the coverage (which
appeared a bit lacking in the model). The diminishing of most cloudiness
should be underway across the wrn two thirds of the PAH forecast
area by midday, with a possible resurgence in the I-64 corridor during
the afternoon. It appears that the clearing pattern is generally
associated with a 700 mb trof axis which is forecast to move ewd
through the cyclonic pattern aloft. After today, opaque cloud cover
should be minimal.
An arctic air mass will continue to filter into the region through
Fri night, before easing off to the east on Sat. The mid/upper
pattern will take on brief ridging ahead of the next system. Low
level flow should have enough time to turn to the south by Sat
afternoon, giving a limited boost to temps. Measurable pcpn is
possible in the afternoon, first rainfall, then perhaps some
snowfall in the nwrn half of our region toward evening as the lower trop
cools. The area with the best chance of measuring more than a
tenth of an inch of snow will be the higher elevations of the
Ozark Foothills. Temps much below average will continue in the
short term period.
.LONG TERM...(Saturday night through Wednesday)
Issued at 350 AM CST THU NOV 13 2014
Low to medium forecast confidence in the long term with models still
not in good agreement.
Overrunning precipitation due to isentropic upglide should be
underway at the beginning of the long term period. Thermal profiles
still indicating all precipitation to be snow, but models still
quite different on QPF amounts. Models do however indicate the best
chances for snow Saturday night should be over the northwest half of
the CWA. The latest GFS run still the colder of the extended models.
A cold front is still expected to blast across the CWA on Sunday.
For Sunday morning, thermal profiles would suggest a rain/snow/sleet
mix over the southeast third of our CWA with snow elsewhere. For
Sunday afternoon models are indicating the lower levels warming up a
bit, so expect snow over the northwest third, a rain/snow/sleet mix
over the middle third, with all rain over the southeast third.
Sunday evening, in the wake of the frontal passage, the combination
of the approach of a short wave, an inverted trough over the deep
south, and plenty of moisture will induce a deformation zone and
produce yet another overrunning precipitation scenario but with more
impressive QPF amounts than Saturday night. As the cooler
post-frontal air overspreads the region Sunday evening, expect a
snow/sleet mix over the southeast third of the CWA, with all snow
elsewhere.
After midnight Sunday night precipitation should change over to all
snow. Snow may linger over the far southeast portions of our CWA
Monday morning, but little to no additional snow accumulation is
expected. Total snow accumulation from Saturday night through Sunday
night should max out somewhere in the 1.5-2.0 inch range area-wide,
with the majority falling Sunday night.
Beyond that, high pressure at the surface and flow aloft becoming
more northwest should produce dry conditions through the remainder
of the long term period along with below normal temperatures.
&&
.AVIATION...
Issued at 1147 PM CST THU NOV 13 2014
Apparently the cloud depth was narrow enough at KEVV/KOWB to erode
during the evening hours. With the 06z Thursday TAF issuance, the
trend toward broken VFR ceilings was continued. Unrestricted
ceilings should dominate for the latter 12 hours of the forecast period.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
SHORT TERM...DB
LONG TERM...JP
AVIATION...DB
AREA FORECAST DISCUSSION
NWS PADUCAH KY
1148 PM CST Wed Nov 12 2014
.UPDATE...
Issued at 840 PM CST WED NOV 12 2014
Just updated most notably for cloud trends through the night. The
west edge of the low clouds has slowed to a crawl from near
Evansville Indiana to near Murray Kentucky, but widespread mid-
level clouds have developed over the remainder of the area.
Guidance still pushes the low clouds east of the area by
midnight, but keeps the mid clouds over the area through much of
the night, before clearing in the morning.
It appears that there will be a lull in the north winds late this
evening and into the overnight hours, but the latest model data
shows a tightening pressure gradient toward morning, so winds will
likely pick up significantly by daybreak. The combination of clouds
and winds should keep temperatures from dropping much tonight. Lows
were hardly changed across the region with this update.
Noticed single digit dewpoints as close as central Missouri as of
02Z. With the continued northwest winds, our dewpoint forecast may
not be low even across at least the northwest half of the area
during the day Thursday.
&&
.SHORT TERM...(Tonight through Friday night)
Issued at 121 PM CST WED NOV 12 2014
Clouds continued to cover the CWFA early this afternoon, keeping
temperatures from rising much as well. Breaks continue to head SE
from Missouri and west IL. Should see a gradual decrease with
time. RAP was a decent guide in handling the general trend.
At the surface, strong high pressure with unseasonably cold air will
continue to move southeast, overspreading the area. It should
finally be centered over our area by 12z Saturday. Meanwhile, a
double barrel low over the northern Plains and Great Lakes will
phase, with one low heading up through Quebec, while energy from the
western end swings across the Upper Midwest and Great Lakes tonight
through Thursday. Expect mainly mid and upper level clouds tonight
through early Thursday, followed by decreasing clouds. NW flow will
persist as energy dives south into the Rockies from west Canada
Friday through Friday night. Dry weather is forecast with just a few
clouds from Thursday afternoon through Friday night.
As far as temperatures, followed a blend of the slightly colder MOS
and standard model output. MOS appears to have finally caught on to
the degree of cold air. Prior output from a few days ago, MOS had
its typical mild climo influence bias, while the standard raw model
output was better identifying how cold it would likely be. No real
model preference in the short term tonight and beyond. A GFS/NAM
blend was used.
.LONG TERM...(Saturday through Wednesday)
Issued at 121 PM CST WED NOV 12 2014
Main focus continues to be on weekend precip (even wintry) chances,
and the continued cold. Both the GFS and ECMWF ops runs continue to
suffer run to run inconsistencies, especially with respect to timing
in response to the evolution of the mid tropospheric flow pattern
over the CONUS east of the Rockies. The GFS is trending toward, and
ECMWF back towards separate energy that may pinch off the main trof
over the Southern Rockies, eventually heading east over the weekend.
The models continue to advertise a lead weak s/wv that will move
from the southern Rockies to Mississippi Valley region Saturday into
Saturday night. May see rather light wintry mix into SEMO by
afternoon. Will continue with light rain/light snow mention here.
Saturday night, as the wave moves ENE, the models continue to hint
at a band of light precip (parameters suggest light snow), for
parts of the area. Not much QPF, so still not expecting much. But
any minor coating of light snow around here...well.
The models are not showing much now for Sunday, thus will keep PoPs
on the low side. As some slightly warmer boundary layer air advects
into the SE 1/2 of the CWFA (still favor the slightly colder GFS),
will use a mix (including light rain) mention, with just light
snow NW 1/2. As the aforementioned mid level wave moves east
Sunday and phases with the parent broad mid level trof by Sunday
night, models ramp up moisture a bit over the SE 1/2 of the area.
This is slower, so PoPs will need to linger Sunday night, vs.
early depictions of ending things by Sunday evening. This is where
the back and forth (changing forecast) has been most prominent.
Again types, light wintry mix possible SE 1/2, just a small chance
of light snow NW 1/2. The GFS remains quicker departing chances,
while the ECMWF lingers the chance now through early Monday.
Given the adjustments and changes that continue to go on within the
models, will keep PoPs in check and only in the chance category for
now. Otherwise continued cold through early next week. Dry weather
returns for most of Monday on through Wednesday.
&&
.AVIATION...
Issued at 1147 PM CST WED NOV 12 2014
Apparently the cloud depth was narrow enough at KEVV/KOWB to erode
during the evening hours. With the 06z Thursday TAF issuance, the
trend toward broken VFR ceilings was continued. Unrestricted
ceilings should dominate for the latter 12 hours of the forecast period.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
UPDATE...DRS
AVIATION...Smith
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
1237 PM EST THU NOV 13 2014
.SYNOPSIS...
LOW PRESSURE DEVELOPS ALONG A STALLED FRONT OVER THE CAROLINAS
THIS AFTERNOON...AND STRENGTHENS OFF THE COAST TONIGHT. HIGH
PRESSURE BUILDS INTO THE REGION FRIDAY THROUGH SUNDAY
MORNING...USHERING IN MUCH BELOW NORMAL TEMPERATURES. THE NEXT
CHANCE FOR RAIN COMES SUNDAY NIGHT THROUGH MONDAY NIGHT.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
QUITE THE DIFFERENCE IN CONDS FM 24 HRS AGO. MUCH COOLER AMS HAS
SETTLED OVR THE RGN ON NNW WNDS. PLENTY OF CLDNS COVERS THE FA
ATTM...AND THAT WILL CONT THROUGH THE REST OF THE DAY. PATCHY VERY
LGT RA TRACKS ACRS PORTIONS OF THE AREA (MNLY INLAND) SO FAR THIS
MRNG. WILL HANG ONTO SLGT CHC POPS FOR THOSE AREAS INTO THE AFTN
HRS. OTRW...AWAITING RA TO DEVELOP/ARRIVE LT THIS AFTN/EARLY EVE
AS VERY WK WAVE OF LO PRES TRACKS NE INVOF CSTL PLAIN IN ERN NC.
LTL EVIDENCE OF PCPN SO FAR TO THE SSW...HWVR THAT SHOULD CHANGE
DURG THE AFTN HRS (THOUGH 15Z/13 RUC KEEPS BULK OF ANY PCPN
LARGELY TO AREAS OVR NE NC THROUGH 00Z/14). WILL HAVE POPS INCRSG
TO 30-50% AFT 21Z/13 (HIGHEST S). TEMPS RMNG IN THE M/U40S N AND
CNTRL LOCATIONS...FALLING INTO THE 40S/L50S FAR SE VA/CSTL NE NC.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
BEST CHANCE FOR PRECIP IN MOST AREAS LOOKS TO OCCUR IN THE EVENING
HRS...AS SECONDARY SURGE OF COLD AIR ARRIVES WITH THE COLD FRONT
AND THE SFC LOW INTENSIFIES OFFSHORE. PRECIP LINGERS INTO THE EARLY
AM HRS FRI ALONG THE COAST. WILL BE ALL RAIN INTIALLY THIS
EVE...WITH COLDER AIR PUSHING IN FROM THE NW BETWEEN 03-06Z. MAIN
AREA OF FORCING/UVM DEPARTING AFTER MDNGT AS COOLING BEGINS.
TIMING WOULD BE CRUCIAL FOR ANY PSBL MIXED PTYPE (RA/SN) AS BNDRY
LYR IS THE LAST TO SUFFICIENTLY COOL. WILL CONTINUE TO CONFINE
MENTION OF SN TO AREAS MNLY N OF A LINE FM FVX TO RIC TO SBY
(EARLIEST/LT THU EVE W...AFT MDNGT E). NO IMPACT (FM ANY FROZEN
PCPN) IS XPCD. LO TEMPS THU NGT ARND 30F FAR NW TO THE U30S/ARND
40F RIGHT AT THE CST.
PCPN WINDING DOWN QUICKLY BY EARLY FRI MRNG W/ CLDS SLO TO EXIT
TO THE E. GUSTY NNW WNDS USHER IN COLD/DRY AIR ON FRI...SETTING UP
A VERY COLD NGT FRI NGT W/ SKC AND DIMINISHING WNDS. HIGHS FRI IN
THE MID-UPPER 40S. PTNTL EXISTS FOR A FREEZE FM KPHF TO KORF/KNTU
(LAST RMNG AREAS TO BE IN AKQ FROST/FREEZE PROGRAM)...WILL DEPEND
ON WIND SPEED AND DIRECTION...BUT MOST OF THESE AREAS EXCEPT THE
IMMEDIATE COAST APPEAR TO HAVE A GOOD CHANCE FOR MINS AT OR BELOW
32 F. WELL INALND A HARD FREEZE APPEARS LIKELY WITH LOWS IN THE
LOWER TO MID 20S.
SAT WILL BE DRY/CHILLY W/ SFC HI PRES SETTLING OVR THE RGN FM THE
WNW. LIGHETER WINDS AND MOSTLY SUNNY WITH HIGHS ONLY IN THE MID
40S MOST AREAS.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AN ACTIVE PATTERN WITH GENERALLY BELOW NORMAL TEMPERATURES IS
INDICATED. AS A PIECE OF THE ARCTIC HIGH PRESSURE FROM THE PLAINS
STATES MOVES EAST AND OFF THE COAST SUNDAY...A SECONDARY FRONT AND
GENERAL AREA OF LOW PRESSURE AFFECTS THE EASTERN PART OF THE NATION
LATE SUNDAY THROUGH EARLY TUESDAY.
SUNDAY IS NOW FORECAST TO BE DRY. BOTH THE 12Z RUNS OF THE GFS
AND EURO INDICATE LOW PRESSURE MOVING OUT THE SOUTHWEST WITH THE
PERIOD OF PCPN LATER THAN PREVIOUS FORECASTS. HAVE LIKELY POPS
ACROSS THE CWA FOR BOTH SUNDAY NIGHT AND MONDAY. THE LOW PULLS OFF
TO THE NORTHEAST MONDAY NIGHT WITH PCPN ENDING FROM THE WEST. DRY
WEATHER IS INDICATED FOR TUESDAY THROUGH WEDNESDAY.
LOW LEVEL THICKNESSES ARGUE AGAINST SNOW AT THIS TIME WITH THE
AFOREMENTIONED SYSTEM. SOME LIGHT FREEZING RAIN OR SLEET OVER THE
PIEDMONT COULD OCCUR AT THE INITIATION OF THE EVENT SUNDAY NIGHT
WITH LOW DEW POINTS IN PLACE BUT CONFIDENCE IS LOW AND LEFT THIS OUT
OF THE FORECAST.
HIGH TEMPERATURES SUNDAY AND MONDAY RANGE FROM THE UPR 40S NW TO MID
50S SE EXCEPT WARMING TO THE UPR 50S TO LWR 60S FAR SE VA AND NE NC
MONDAY. HIGHS RANGE THROUGH THE 40S TUESDAY AND WEDNESDAY.
LOWS SUNDAY MORNING WILL BE A BIT WARMER THAN THOSE OF SATURDAY
MORNING...RANGING FROM THE MID 20S INLAND TO NEAR FREEZING AT THE
COAST. LOWS IN THE 30S INLAND TO LWR 40S AT THE COAST MONDAY MORNING
COOL TO THE 30S TUESDAY MORNING AND THE 20S WEDNESDAY MORNING.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
OVC CIGS (2000-3000 FT) ARE ALREADY FOUND ACROSS THE AREA THIS
AFTERNOON. EXPECT THESE CIGS TO CONTINUE INTO TONIGHT. LOW PRESSURE
MOVES NE OFF THE COAST TONIGHT AND SHOULD PROVIDE THE FOCUS FOR
SOME -RA OR -DZ AT ALL TAF SITES BETWEEN 22Z-06Z...BEFORE PCPN
ENDS FROM WEST TO EAST OVERNIGHT. CONDITIONS EXPECTED TO GENERALLY
REMAIN MVFR BUT IFR CERTAINLY POSSIBLE. A FEW SNOW FLAKES ARE
POSSIBLE AT RIC/SBY LATE TNGT/EARLY FRI MORNING AS PCPN ENDS.
STRONG NORTHERLY WINDS THEN USHER EVEN DRIER AIR INTO THE REGION
BEHIND THE EXITING LOW FOR FRIDAY.
OUTLOOK...DRY WX AND VFR CONDITIONS EXPECTED EVERYWHERE FROM FRI
INTO EARLY SUN. GOOD CHC FOR MORE RAIN SUN NGT INTO MON NGT WITH
POSSIBLE IFR CONDITIONS.
&&
.MARINE...
NNE WINDS WILL WEAKEN A BIT DURING TODAY...BUT STRONG NNW WINDS
(15 TO 25 KT WITH GUSTS TO ARND 30 KT) ARE EXPECTED LATER THIS
EVENG INTO AT LEAST FRI EVENG...DUE TO LO PRES TRACKING NNE OFF
THE MID ATLC CST TWD THE CANADIAN MARITIMES AND COLD HI PRES BLDNG
IN FM THE W. WINDS/CONDITIONS WILL THEN CALM DOWN SAT THRU SUN
MORNG...AS HI PRES BLDS OVR THE AREA AND JUST OFFSHR.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 PM EST FRIDAY FOR ANZ635>638.
SMALL CRAFT ADVISORY UNTIL 10 PM EST FRIDAY FOR ANZ630>634-650-
652-654-656-658.
&&
$$
SYNOPSIS...ALB/LKB
NEAR TERM...ALB/LKB
SHORT TERM...ALB/LKB
LONG TERM...LKB/LSA
AVIATION...JDM
MARINE...TMG
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
1031 AM EST THU NOV 13 2014
.SYNOPSIS...
LOW PRESSURE DEVELOPS ALONG A STALLED FRONT OVER THE CAROLINAS
THIS AFTERNOON...AND STRENGTHENS OFF THE COAST TONIGHT. HIGH
PRESSURE BUILDS INTO THE REGION FRIDAY THROUGH SUNDAY
MORNING...USHERING IN MUCH BELOW NORMAL TEMPERATURES. THE NEXT
CHANCE FOR RAIN COMES SUNDAY NIGHT THROUGH MONDAY NIGHT.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
QUITE THE DIFFERENCE IN CONDS FM 24 HRS AGO. MUCH COOLER AMS HAS
SETTLED OVR THE RGN ON NNW WNDS. PLENTY OF CLDNS COVERS THE FA
ATTM...AND THAT WILL CONT THROUGH THE REST OF THE DAY. PATCHY VERY
LGT RA TRACKS ACRS PORTIONS OF THE AREA (MNLY INLAND) SO FAR THIS
MRNG. WILL HANG ONTO SLGT CHC POPS FOR THOSE AREAS INTO THE AFTN
HRS. OTRW...AWAITING RA TO DEVELOP/ARRIVE LT THIS AFTN/EARLY EVE
AS VERY WK WAVE OF LO PRES TRACKS NE INVOF CSTL PLAIN IN ERN NC.
LTL EVIDENCE OF PCPN SO FAR TO THE SSW...HWVR THAT SHOULD CHANGE
DURG THE AFTN HRS (THOUGH 15Z/13 RUC KEEPS BULK OF ANY PCPN
LARGELY TO AREAS OVR NE NC THROUGH 00Z/14). WILL HAVE POPS INCRSG
TO 30-50% AFT 21Z/13 (HIGHEST S). TEMPS RMNG IN THE M/U40S N AND
CNTRL LOCATIONS...FALLING INTO THE 40S/L50S FAR SE VA/CSTL NE NC.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
BEST CHANCE FOR PRECIP IN MOST AREAS LOOKS TO OCCUR IN THE EVENING
HRS...AS SECONDARY SURGE OF COLD AIR ARRIVES WITH THE COLD FRONT
AND THE SFC LOW INTENSIFIES OFFSHORE. PRECIP LINGERS INTO THE EARLY
AM HRS FRI ALONG THE COAST. WILL BE ALL RAIN INTIALLY THIS
EVE...WITH COLDER AIR PUSHING IN FROM THE NW BETWEEN 03-06Z. MAIN
AREA OF FORCING/UVM DEPARTING AFTER MDNGT AS COOLING BEGINS.
TIMING WOULD BE CRUCIAL FOR ANY PSBL MIXED PTYPE (RA/SN) AS BNDRY
LYR IS THE LAST TO SUFFICIENTLY COOL. WILL CONTINUE TO CONFINE
MENTION OF SN TO AREAS MNLY N OF A LINE FM FVX TO RIC TO SBY
(EARLIEST/LT THU EVE W...AFT MDNGT E). NO IMPACT (FM ANY FROZEN
PCPN) IS XPCD. LO TEMPS THU NGT ARND 30F FAR NW TO THE U30S/ARND
40F RIGHT AT THE CST.
PCPN WINDING DOWN QUICKLY BY EARLY FRI MRNG W/ CLDS SLO TO EXIT
TO THE E. GUSTY NNW WNDS USHER IN COLD/DRY AIR ON FRI...SETTING UP
A VERY COLD NGT FRI NGT W/ SKC AND DIMINISHING WNDS. HIGHS FRI IN
THE MID-UPPER 40S. PTNTL EXISTS FOR A FREEZE FM KPHF TO KORF/KNTU
(LAST RMNG AREAS TO BE IN AKQ FROST/FREEZE PROGRAM)...WILL DEPEND
ON WIND SPEED AND DIRECTION...BUT MOST OF THESE AREAS EXCEPT THE
IMMEDIATE COAST APPEAR TO HAVE A GOOD CHANCE FOR MINS AT OR BELOW
32 F. WELL INALND A HARD FREEZE APPEARS LIKELY WITH LOWS IN THE
LOWER TO MID 20S.
SAT WILL BE DRY/CHILLY W/ SFC HI PRES SETTLING OVR THE RGN FM THE
WNW. LIGHETER WINDS AND MOSTLY SUNNY WITH HIGHS ONLY IN THE MID
40S MOST AREAS.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AN ACTIVE PATTERN WITH GENERALLY BELOW NORMAL TEMPERATURES IS
INDICATED. AS A PIECE OF THE ARCTIC HIGH PRESSURE FROM THE PLAINS
STATES MOVES EAST AND OFF THE COAST SUNDAY...A SECONDARY FRONT AND
GENERAL AREA OF LOW PRESSURE AFFECTS THE EASTERN PART OF THE NATION
LATE SUNDAY THROUGH EARLY TUESDAY.
SUNDAY IS NOW FORECAST TO BE DRY. BOTH THE 12Z RUNS OF THE GFS
AND EURO INDICATE LOW PRESSURE MOVING OUT THE SOUTHWEST WITH THE
PERIOD OF PCPN LATER THAN PREVIOUS FORECASTS. HAVE LIKELY POPS
ACROSS THE CWA FOR BOTH SUNDAY NIGHT AND MONDAY. THE LOW PULLS OFF
TO THE NORTHEAST MONDAY NIGHT WITH PCPN ENDING FROM THE WEST. DRY
WEATHER IS INDICATED FOR TUESDAY THROUGH WEDNESDAY.
LOW LEVEL THICKNESSES ARGUE AGAINST SNOW AT THIS TIME WITH THE
AFOREMENTIONED SYSTEM. SOME LIGHT FREEZING RAIN OR SLEET OVER THE
PIEDMONT COULD OCCUR AT THE INITIATION OF THE EVENT SUNDAY NIGHT
WITH LOW DEW POINTS IN PLACE BUT CONFIDENCE IS LOW AND LEFT THIS OUT
OF THE FORECAST.
HIGH TEMPERATURES SUNDAY AND MONDAY RANGE FROM THE UPR 40S NW TO MID
50S SE EXCEPT WARMING TO THE UPR 50S TO LWR 60S FAR SE VA AND NE NC
MONDAY. HIGHS RANGE THROUGH THE 40S TUESDAY AND WEDNESDAY.
LOWS SUNDAY MORNING WILL BE A BIT WARMER THAN THOSE OF SATURDAY
MORNING...RANGING FROM THE MID 20S INLAND TO NEAR FREEZING AT THE
COAST. LOWS IN THE 30S INLAND TO LWR 40S AT THE COAST MONDAY MORNING
COOL TO THE 30S TUESDAY MORNING AND THE 20S WEDNESDAY MORNING.
&&
.AVIATION /16Z THURSDAY THROUGH MONDAY/...
SCT TO BKN SC/AC (4000-9000 FT) WILL SPREAD INTO AND ACRS THE
REGION DURING TODAY...AS WEAK LO PRES DEVELOPS ALNG THE NC CST.
LWR SC (MVFR CIGS) LIKELY BY EARLY THIS EVENG...AND WILL LAST INTO
THE OVRNGT AT ALL TAF SITES WITH -RA POSSIBLE EVERYWHERE...AS THE
LO MOVES NE OFF THE MID ATLC AND SRN NEW ENGLAND CST WHILE
INTENSIFYING A BIT. A FEW FLURRIES POSSIBLE AT RIC/SBY LATE
TNGT/EARLY FRI MORNG BEFORE PCPN ENDS. STRONG NORTHERLY WINDS
THEN USHER EVEN DRIER AIR INTO THE REGION BEHIND THE EXITING LO
FOR LATE TNGT INTO FRI AFTN.
OUTLOOK...DRY WX AND VFR CONDITIONS EXPECTED EVERYWHERE FM MID
MORNG FRI INTO EARLY SUN. GOOD CHC FOR MORE RAIN SUN NGT INTO MON
NGT WITH POSSIBLE IFR CONDITIONS.
&&
.MARINE...
NNE WINDS WILL WEAKEN A BIT DURING TODAY...BUT STRONG NNW WINDS
(15 TO 25 KT WITH GUSTS TO ARND 30 KT) ARE EXPECTED LATER THIS
EVENG INTO AT LEAST FRI EVENG...DUE TO LO PRES TRACKING NNE OFF
THE MID ATLC CST TWD THE CANADIAN MARITIMES AND COLD HI PRES BLDNG
IN FM THE W. WINDS/CONDITIONS WILL THEN CALM DOWN SAT THRU SUN
MORNG...AS HI PRES BLDS OVR THE AREA AND JUST OFFSHR.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 PM EST FRIDAY FOR ANZ635>638.
SMALL CRAFT ADVISORY UNTIL 10 PM EST FRIDAY FOR ANZ630>634-650-
652-654-656-658.
&&
$$
SYNOPSIS...ALB/LKB
NEAR TERM...ALB/LKB
SHORT TERM...ALB/LKB
LONG TERM...LKB/LSA
AVIATION...TMG
MARINE...TMG
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1250 PM EST THU NOV 13 2014
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 316 AM EST THU NOV 13 2014
SNOW SHOWERS...LOCALLY HEAVY ARE EXPECTED TODAY SOUTH OF
INTERSTATE 96 AND WEST OF US-131. WHILE THE SNOW SHOWERS WILL
DIMINISH SOME LATE THIS AFTERNOON THEY WILL CONTINUE INTO FRIDAY
AFTERNOON RESULTING IN LOCAL ACCUMULATIONS AS HIGH AS 9 INCHES IN
PARTS OF ALLEGAN AND OTTAWA COUNTIES.
SNOW SHOWERS WILL ALSO RESULT IN 4 TO 6 INCHES OF SNOW WEST OF
US-131 AND NORTH OF MUSKEGON INTO FRIDAY AFTERNOON. ELSEWHERE
LIGHT SNOW SHOWERS WILL CONTINUE INTO FRIDAY WITH AN INCH OR LESS
OF ACCUMULATION.
THE UNSEASONABLY COLD TEMPERATURES...NEAR TO BELOW FREEZING WILL
CONTINUE THROUGH MOST OF NEXT WEEK. THE SNOW SHOWERS SHOULD COME
TO AN END SATURDAY ONLY TO START BACK UP ON SUNDAY AND CONTINUE
INTO WEDNESDAY. A SECOND ARCTIC FRONT WILL BRING EVEN COLDER AIR
IN THE TUESDAY TO WEDNESDAY TIME FRAME.
&&
.UPDATE...
ISSUED AT 824 AM EST THU NOV 13 2014
BASED ON REPORTS OF UP TO 3.5 INCHES IN MUSKEGON COUNTY AND THAT
MKG HAS MODERATE TO HEAVY SNOW WITH A SNOW INCREASE ONE AT 8 AM...
WE RECENTLY HAVE HAD REPORTS OF SCHOOL BUSES HAVING PROBLEMS
MAKING UP HILLS AND SOME EMERGENCY VEHICLES HAVING PROBLEMS
STOPPING DUE TO THE SNOW AND ICE. SO...IT MAKES SENSE INCLUDE
MUSKEGON IN THE ADVISORY. ALSO I EXPECT THE SNOW TO CONTINUE THERE
HEAVY AT TIMES FOR A FEW MORE HOURS YET. THEN THE SNOW WILL
REDEVELOP AGAIN THIS EVENING. I COULD SEE 5 TO 7 INCHES BY MIDDAY
TOMORROW IN PARTS OF SOUTHERN AND CENTRAL MUSKEGON COUNTY.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 316 AM EST THU NOV 13 2014
THE WINTER WEATHER ADVISORY IS OUR PRIMARY FOCUS THIS MORNING. IT
LOOKS VERY GOOD FOR THE HEAVIER SNOWFALL OVER OTTAWA AND ALLEGAN
COUNTIES THIS MORNING BUT IT LOOKS LESS GOOD FOR THE HEAVIER
SNOWFALLS OVER OUR NW CWA EVEN SO... I CONTINUED THE ADVISORY
THERE SINCE THAT IS A TYPICAL PLACE FOR HEAVIER SNOW WITH A WEST
TO NORTHWEST WIND FLOW.
BASED ON THE LATEST DATA FROM OUR HIGH RESOLUTIONS MODELS...
GETTING HEAVIER SNOWFALL AMOUNTS OVER OTTAWA AND ALLEGAN COUNTY
THIS MORNING INTO EARLY THIS AFTERNOON STILL LOOKS GOOD. THE HEAVY
SNOW BANDS ARE FORECAST TO OCCUR FROM MID MORNING INTO EARLY THIS
AFTERNOON OVER ALLEGAN AND OTTAWA COUNTIES BY THE RAP...NAM AND
HRRR MODELS. THE HRRR HAS CONSISTENTLY SHOWN 4 TO 7 INCHES BETWEEN
6 AM AND AND 2 PM THIS AFTERNOON IN TWO BANDS OVER OTTAWA AND
ALLEGAN COUNTIES. THIS IS SIMILAR TO THE OUTPUT OF THE NAMDNG55. SINCE
THE LATEST RADAR IS CURRENTLY SHOWING A SIGNIFICANT INCREASE IN
INTENSITY AND BIV HAS SHOW VISIBILITIES DOWN TO NEAR 1 MILE
ALREADY... I HAVE TO BELIEVE THE LOCALLY HEAVIER SNOW BANDS ARE
MORE THAN POSSIBLE. WHAT ALSO GOES ALONG WITH THIS IS THE LIFT IF
THE DGZ IS IMPRESSIVE ON ALL THREE MODELS OVER THOSE TWO COUNTIES.
THE INVERSION HEIGHTS LIFT TO NEAR 11000 FT BY MID MORNING TOO. ALL
OF THAT HELPS THE CAUSE OF HEAVIER SNOW BANDS IN OUR ADVISORY
AREA.
WHAT IS FORCING ALL OF THIS IS A SIGNIFICANT SHORTWAVE THAT MOVES
THROUGH THE CWA DURING THE MIDDAY HOURS. IT IS THIS SHORTWAVE THE
FINALLY PUSHES THE POLAR JET CORE SOUTH OF MICHIGAN. THAT WAS
FORECAST TO HAPPEN SOONER BY EARLIER RUNS OF THE MODELS BUT THIS
SHORTWAVE WILL DO THE TRICK AND PUT SOUTHWEST MICHIGAN IN THE DEEP
COLD AIR INTO FRIDAY EVENING. ONCE THE SHORTWAVE IS THROUGH THE
INTENSITY OF THE SNOW SHOWERS WILL DECREASE BUT WE WILL STILL HAVE
LIFT IN THE DGZ WITH NEAR SATURATION DUE OVER ICE THROUGH FRIDAY
AFTERNOON SO THE SNOW SHOWERS WILL CONTINUE INTO FRIDAY AFTERNOON
FOR SURE.
FRIDAY NIGHT INTO SATURDAY THE SURFACE HIGH MOVES IN AND BY MID
MORNING SATURDAY THE AIR BECOMES SO DRY THAT GETTING LAKE EFFECT
CLOUDS WILL HE HARD TO DO...EVEN WITH THE 20C DIFFERENCE BETWEEN
THE LAKE TEMPERATURE AND 850 MB. SO WE SHOULD FINALLY SEE A DRY
PERIOD.
INLAND AREAS TODAY THROUGH FRIDAY WILL SEE OCCASIONAL SNOW SHOWER
WITH THE HELP OF DAY TIME MIXING BRINGING THE SHOWER INLAND. ALSO
THE WEST NORTHWEST WINDS WILL HELP THAT CAUSE TOO.
TEMPERATURES SHOULD LARGELY STAY NEAR TO BELOW FREEZING ALL THREE
AFTERNOONS AND FALL INTO THE 20S AT NIGHT. CLOUDS DUE TO THE WEST
TO NORTHWEST WINDS WILL KEEP IT FROM GETTING MUCH COLDER THAN THAT.
.LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 316 AM EST THU NOV 13 2014
THE COLD SNOWY PATTERN WILL CONTINUE THROUGH THE LONG TERM. HOWEVER
BY LATE WEDNESDAY...MODELS ARE HINTING THAT THE CORE OF THE COLD AIR
WILL START TO LIFT OUT.
THE MAIN FOCUS IS ON MONDAY AND TUESDAY. THAT/S THE TIME FRAME WHEN A
DEEP TROUGH WILL MOVE OVER THE GREAT LAKES AND PRODUCE ANOTHER BLAST
OF ARCTIC AIR. BOTH THE GFS AND ECMWF ARE SIMILAR IN TIMING AND
STRENGTH OF THE UPPER TROUGH. H8 TEMPS FALL TO -16C BY TUESDAY
AFTERNOON. WNW BOUNDARY LAYER WINDS SHOULD RESULT IN LAKE EFFECT
SNOW MONDAY THROUGH TUESDAY. THE DGZ DOES FALL TO AROUND 4K FT...BUT
IS PRETTY TYPICAL FOR THIS TYPE OF COLD AIR. WE/RE LIKELY GOING TO
SEE SEVERAL INCHES OF SNOWFALL DURING THIS TIME FRAME AND WE BOOSTED
POPS TO ACCOUNT FOR IT.
PRIOR TO THE BLAST OF ARCTIC AIR ARRIVING SUNDAY NIGHT...WE/LL SEE
SOME WARM AIR ADVECTION SNOW SATURDAY NIGHT THAT WILL CONTINUE INTO
SUNDAY. ACCUMS IN THE 1-3 INCH RANGE LOOK REASONABLE SATURDAY NIGHT
BASED ON MIXING RATIOS AND THE STRENGTH OF THE ISENTROPIC LIFT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1243 PM EST THU NOV 13 2014
LAKE EFFECT SNOW SHOWERS WILL PERSIST THROUGH MUCH OF THE PERIOD.
AIRPORTS CLOSER TO LAKE MICHIGAN WILL SEE GREATER IMPACTS.
TEMPORARILY IFR IS LIKELY THROUGH THE AFTERNOON FOR
KGRR...KMKG...KAZO AND KBTL. FURTHER INLAND...WHILE IFR WAS NOT
INCLUDED IN THE FORECAST...THE RISK IS NOT ZERO.
SNOW SHOWERS WILL REMAIN NUMEROUS THROUGH TONIGHT WITH IFR MOST
LIKELY FOR KMKG...KGRR AND KAZO. KBTL WILL BE CLOSE TO THE HEAVY
SNOW BANDS...BUT I WAS NOT CONFIDENT ENOUGH TO GO WITH THE GREATER
IMPACTS THERE.
ICING WILL BE A CONCERN AS WELL FOR ALL SITES...ESPECIALLY TONIGHT
AND FRIDAY.
&&
.MARINE...
ISSUED AT 316 AM EST THU NOV 13 2014
I CONTINUED THE SMALL CRAFT ADVISORY AS IS THROUGH FRIDAY
AFTERNOON. IT WOULD SEEM HIGH PRESSURE BUILDING INTO THE AREA
DURING FRIDAY AFTERNOON SHOULD DECREASE THE PRESSURE GRADIENT AND
ALLOW WINDS AND WAVES TO FINALLY SUBSIDE. UNTIL THEN NORTHWEST
WINDS OF 15 TO 25 KNOTS SHOULD PREVAIL.
&&
.HYDROLOGY...
ISSUED AT 310 PM EST WED NOV 12 2014
NO HYDROLOGY CONCERNS FOR THE NEXT WEEK WITH ANY PCPN OVER THE NEXT
WEEK IN THE FORM OF SNOW AND UNSEASONABLY COLD TEMPS.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...WINTER WEATHER ADVISORY UNTIL 4 PM EST FRIDAY FOR MIZ037-038-043-
050-056-064-071-072.
LM...SMALL CRAFT ADVISORY UNTIL 4 PM EST FRIDAY FOR LMZ844>849.
&&
$$
UPDATE...WDM
SYNOPSIS...WDM
SHORT TERM...WDM
LONG TERM...93
AVIATION...MJS
HYDROLOGY...LAURENS
MARINE...WDM
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
826 AM EST THU NOV 13 2014
LATEST UPDATE...
UPDATE
.SYNOPSIS...
ISSUED AT 316 AM EST THU NOV 13 2014
SNOW SHOWERS...LOCALLY HEAVY ARE EXPECTED TODAY SOUTH OF
INTERSTATE 96 AND WEST OF US-131. WHILE THE SNOW SHOWERS WILL
DIMINISH SOME LATE THIS AFTERNOON THEY WILL CONTINUE INTO FRIDAY
AFTERNOON RESULTING IN LOCAL ACCUMULATIONS AS HIGH AS 9 INCHES IN
PARTS OF ALLEGAN AND OTTAWA COUNTIES.
SNOW SHOWERS WILL ALSO RESULT IN 4 TO 6 INCHES OF SNOW WEST OF
US-131 AND NORTH OF MUSKEGON INTO FRIDAY AFTERNOON. ELSEWHERE
LIGHT SNOW SHOWERS WILL CONTINUE INTO FRIDAY WITH AN INCH OR LESS
OF ACCUMULATION.
THE UNSEASONABLY COLD TEMPERATURES...NEAR TO BELOW FREEZING WILL
CONTINUE THROUGH MOST OF NEXT WEEK. THE SNOW SHOWERS SHOULD COME
TO AN END SATURDAY ONLY TO START BACK UP ON SUNDAY AND CONTINUE
INTO WEDNESDAY. A SECOND ARCTIC FRONT WILL BRING EVEN COLDER AIR
IN THE TUESDAY TO WEDNESDAY TIME FRAME.
&&
.UPDATE...
ISSUED AT 824 AM EST THU NOV 13 2014
BASED ON REPORTS OF UP TO 3.5 INCHES IN MUSKEGON COUNTY AND THAT
MKG HAS MODERATE TO HEAVY SNOW WITH A SNOW INCREASE ONE AT 8 AM...
WE RECENTLY HAVE HAD REPORTS OF SCHOOL BUSES HAVING PROBLEMS
MAKING UP HILLS AND SOME EMERGENCY VEHICELS HAVING PROBLEMS
STOPPING DUE TO THE SNOW AND ICE. SO...IT MAKES SENSE INCLUDE
MUSKEGON IN THE ADVISORY. ALSO I EXPECT THE SNOW TO CONTINUE THERE
HEAVY AT TIMES FOR A FEW MORE HOURS YET. THEN THE SNOW WILL
REDEVELOP AGAIN THIS EVENING. I COULD SEE 5 TO 7 INCHES BY MIDDAY
TOMORROW IN PARTS OF SOUTHERN AND CENTRAL MUSKEGON COUNTY.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 316 AM EST THU NOV 13 2014
THE WINTER WEATHER ADVISORY IS OUR PRIMARY FOCUS THIS MORNING. IT
LOOKS VERY GOOD FOR THE HEAVIER SNOWFALL OVER OTTAWA AND ALLEGAN
COUNTIES THIS MORNING BUT IT LOOKS LESS GOOD FOR THE HEAVIER
SNOWFALLS OVER OUR NW CWA EVEN SO... I CONTINUED THE ADVISORY
THERE SINCE THAT IS A TYPICAL PLACE FOR HEAVIER SNOW WITH A WEST
TO NORTHWEST WIND FLOW.
BASED ON THE LATEST DATA FROM OUR HIGH RESOLUTIONS MODELS...
GETTING HEAVIER SNOWFALL AMOUNTS OVER OTTAWA AND ALLEGAN COUNTY
THIS MORNING INTO EARLY THIS AFTERNOON STILL LOOKS GOOD. THE HEAVY
SNOW BANDS ARE FORECAST TO OCCUR FROM MID MORNING INTO EARLY THIS
AFTERNOON OVER ALLEGAN AND OTTAWA COUNTIES BY THE RAP...NAM AND
HRRR MODELS. THE HRRR HAS CONSISTENTLY SHOWN 4 TO 7 INCHES BETWEEN
6 AM AND AND 2 PM THIS AFTERNOON IN TWO BANDS OVER OTTAWA AND
ALLEGAN COUNTIES. THIS IS SIMILAR TO THE OUTPUT OF THE NAMDNG55. SINCE
THE LATEST RADAR IS CURRENTLY SHOWING A SIGNIFICANT INCREASE IN
INTENSITY AND BIV HAS SHOW VISIBILITIES DOWN TO NEAR 1 MILE
ALREADY... I HAVE TO BELIEVE THE LOCALLY HEAVIER SNOW BANDS ARE
MORE THAN POSSIBLE. WHAT ALSO GOES ALONG WITH THIS IS THE LIFT IF
THE DGZ IS IMPRESSIVE ON ALL THREE MODELS OVER THOSE TWO COUNTIES.
THE INVERSION HEIGHTS LIFT TO NEAR 11000 FT BY MID MORNING TOO. ALL
OF THAT HELPS THE CAUSE OF HEAVIER SNOW BANDS IN OUR ADVISORY
AREA.
WHAT IS FORCING ALL OF THIS IS A SIGNIFICANT SHORTWAVE THAT MOVES
THROUGH THE CWA DURING THE MIDDAY HOURS. IT IS THIS SHORTWAVE THE
FINALLY PUSHES THE POLAR JET CORE SOUTH OF MICHIGAN. THAT WAS
FORECAST TO HAPPEN SOONER BY EARLIER RUNS OF THE MODELS BUT THIS
SHORTWAVE WILL DO THE TRICK AND PUT SOUTHWEST MICHIGAN IN THE DEEP
COLD AIR INTO FRIDAY EVENING. ONCE THE SHORTWAVE IS THROUGH THE
INTENSITY OF THE SNOW SHOWERS WILL DECREASE BUT WE WILL STILL HAVE
LIFT IN THE DGZ WITH NEAR SATURATION DUE OVER ICE THROUGH FRIDAY
AFTERNOON SO THE SNOW SHOWERS WILL CONTINUE INTO FRIDAY AFTERNOON
FOR SURE.
FRIDAY NIGHT INTO SATURDAY THE SURFACE HIGH MOVES IN AND BY MID
MORNING SATURDAY THE AIR BECOMES SO DRY THAT GETTING LAKE EFFECT
CLOUDS WILL HE HARD TO DO...EVEN WITH THE 20C DIFFERENCE BETWEEN
THE LAKE TEMPERATURE AND 850 MB. SO WE SHOULD FINALLY SEE A DRY
PERIOD.
INLAND AREAS TODAY THROUGH FRIDAY WILL SEE OCCASIONAL SNOW SHOWER
WITH THE HELP OF DAY TIME MIXING BRINGING THE SHOWER INLAND. ALSO
THE WEST NORTHWEST WINDS WILL HELP THAT CAUSE TOO.
TEMPERATURES SHOULD LARGELY STAY NEAR TO BELOW FREEZING ALL THREE
AFTERNOONS AND FALL INTO THE 20S AT NIGHT. CLOUDS DUE TO THE WEST
TO NORTHWEST WINDS WILL KEEP IT FROM GETTING MUCH COLDER THAN THAT.
.LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 316 AM EST THU NOV 13 2014
THE COLD SNOWY PATTERN WILL CONTINUE THROUGH THE LONG TERM. HOWEVER
BY LATE WEDNESDAY...MODELS ARE HINTING THAT THE CORE OF THE COLD AIR
WILL START TO LIFT OUT.
THE MAIN FOCUS IS ON MONDAY AND TUESDAY. THAT/S THE TIME FRAME WHEN A
DEEP TROUGH WILL MOVE OVER THE GREAT LAKES AND PRODUCE ANOTHER BLAST
OF ARCTIC AIR. BOTH THE GFS AND ECMWF ARE SIMILAR IN TIMING AND
STRENGTH OF THE UPPER TROUGH. H8 TEMPS FALL TO -16C BY TUESDAY
AFTERNOON. WNW BOUNDARY LAYER WINDS SHOULD RESULT IN LAKE EFFECT
SNOW MONDAY THROUGH TUESDAY. THE DGZ DOES FALL TO AROUND 4K FT...BUT
IS PRETTY TYPICAL FOR THIS TYPE OF COLD AIR. WE/RE LIKELY GOING TO
SEE SEVERAL INCHES OF SNOWFALL DURING THIS TIME FRAME AND WE BOOSTED
POPS TO ACCOUNT FOR IT.
PRIOR TO THE BLAST OF ARCTIC AIR ARRIVING SUNDAY NIGHT...WE/LL SEE
SOME WARM AIR ADVECTION SNOW SATURDAY NIGHT THAT WILL CONTINUE INTO
SUNDAY. ACCUMS IN THE 1-3 INCH RANGE LOOK REASONABLE SATURDAY NIGHT
BASED ON MIXING RATIOS AND THE STRENGTH OF THE ISENTROPIC LIFT.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 622 AM EST THU NOV 13 2014
LAKE EFFECT SNOW SHOWERS WILL PREVAIL THROUGH TOMORROW BUT THE
MORE INTENSE SNOW SHOWERS WILL BE THIS MORNING...NEAR THE LAKE
SHORE (MKG)...POSSIBLY REACHING GRR AND AZO/BTL. LAN AND JXN
SHOULD MOSTLY BE MVFR WITH CIGS AND OCNL SNOW SHOWERS.
THE TAFS ARE WRITTEN TO SHOW MOSTLY VFR CONDITIONS AFTER 18Z BUT I
DO EXPECT THE SNOW BANDS TO MOVE BACK INTO AZO /BTL BY EARLY
EVENING SO I TOOK THEM TO IFR AFTER 02Z. THOSE SNOW BANDS MAY ALSO
IMPACT MKG AND GRR BUT I DID NOT SHOW THAT IN THE TAF FORECAST
SINCE IT SEEMED MORE QUESTIONABLE THEN AT AZO AND BTL.
&&
.MARINE...
ISSUED AT 316 AM EST THU NOV 13 2014
I CONTINUED THE SMALL CRAFT ADVISORY AS IS THROUGH FRIDAY
AFTERNOON. IT WOULD SEEM HIGH PRESSURE BUILDING INTO THE AREA
DURING FRIDAY AFTERNOON SHOULD DECREASE THE PRESSURE GRADIENT AND
ALLOW WINDS AND WAVES TO FINALLY SUBSIDE. UNTIL THEN NORTHWEST
WINDS OF 15 TO 25 KNOTS SHOULD PREVAIL.
&&
.HYDROLOGY...
ISSUED AT 310 PM EST WED NOV 12 2014
NO HYDROLOGY CONCERNS FOR THE NEXT WEEK WITH ANY PCPN OVER THE NEXT
WEEK IN THE FORM OF SNOW AND UNSEASONABLY COLD TEMPS.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...WINTER WEATHER ADVISORY UNTIL 4 PM EST FRIDAY FOR MIZ037-038-043-
050-056-064-071-072.
LM...SMALL CRAFT ADVISORY UNTIL 4 PM EST FRIDAY FOR LMZ844>849.
&&
$$
UPDATE...WDM
SYNOPSIS...WDM
SHORT TERM...WDM
LONG TERM...93
AVIATION...WDM
HYDROLOGY...LAURENS
MARINE...WDM
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
623 AM EST THU NOV 13 2014
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 316 AM EST THU NOV 13 2014
SNOW SHOWERS...LOCALLY HEAVY ARE EXPECTED TODAY SOUTH OF
INTERSTATE 96 AND WEST OF US-131. WHILE THE SNOW SHOWERS WILL
DIMINISH SOME LATE THIS AFTERNOON THEY WILL CONTINUE INTO FRIDAY
AFTERNOON RESULTING IN LOCAL ACCUMULATIONS AS HIGH AS 9 INCHES IN
PARTS OF ALLEGAN AND OTTAWA COUNTIES.
SNOW SHOWERS WILL ALSO RESULT IN 4 TO 6 INCHES OF SNOW WEST OF
US-131 AND NORTH OF MUSKEGON INTO FRIDAY AFTERNOON. ELSEWHERE
LIGHT SNOW SHOWERS WILL CONTINUE INTO FRIDAY WITH AN INCH OR LESS
OF ACCUMULATION.
THE UNSEASONABLY COLD TEMPERATURES...NEAR TO BELOW FREEZING WILL
CONTINUE THROUGH MOST OF NEXT WEEK. THE SNOW SHOWERS SHOULD COME
TO AN END SATURDAY ONLY TO START BACK UP ON SUNDAY AND CONTINUE
INTO WEDNESDAY. A SECOND ARCTIC FRONT WILL BRING EVEN COLDER AIR
IN THE TUESDAY TO WEDNESDAY TIME FRAME.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 316 AM EST THU NOV 13 2014
THE WINTER WEATHER ADVISORY IS OUR PRIMARY FOCUS THIS MORNING. IT
LOOKS VERY GOOD FOR THE HEAVIER SNOWFALL OVER OTTAWA AND ALLEGAN
COUNTIES THIS MORNING BUT IT LOOKS LESS GOOD FOR THE HEAVIER
SNOWFALLS OVER OUR NW CWA EVEN SO... I CONTINUED THE ADVISORY
THERE SINCE THAT IS A TYPICAL PLACE FOR HEAVIER SNOW WITH A WEST
TO NORTHWEST WIND FLOW.
BASED ON THE LATEST DATA FROM OUR HIGH RESOLUTIONS MODELS...
GETTING HEAVIER SNOWFALL AMOUNTS OVER OTTAWA AND ALLEGAN COUNTY
THIS MORNING INTO EARLY THIS AFTERNOON STILL LOOKS GOOD. THE HEAVY
SNOW BANDS ARE FORECAST TO OCCUR FROM MID MORNING INTO EARLY THIS
AFTERNOON OVER ALLEGAN AND OTTAWA COUNTIES BY THE RAP...NAM AND
HRRR MODELS. THE HRRR HAS CONSISTENTLY SHOWN 4 TO 7 INCHES BETWEEN
6 AM AND AND 2 PM THIS AFTERNOON IN TWO BANDS OVER OTTAWA AND
ALLEGAN COUNTIES. THIS IS SIMILAR TO THE OUTPUT OF THE NAMDNG55. SINCE
THE LATEST RADAR IS CURRENTLY SHOWING A SIGNIFICANT INCREASE IN
INTENSITY AND BIV HAS SHOW VISIBILITIES DOWN TO NEAR 1 MILE
ALREADY... I HAVE TO BELIEVE THE LOCALLY HEAVIER SNOW BANDS ARE
MORE THAN POSSIBLE. WHAT ALSO GOES ALONG WITH THIS IS THE LIFT IF
THE DGZ IS IMPRESSIVE ON ALL THREE MODELS OVER THOSE TWO COUNTIES.
THE INVERSION HEIGHTS LIFT TO NEAR 11000 FT BY MID MORNING TOO. ALL
OF THAT HELPS THE CAUSE OF HEAVIER SNOW BANDS IN OUR ADVISORY
AREA.
WHAT IS FORCING ALL OF THIS IS A SIGNIFICANT SHORTWAVE THAT MOVES
THROUGH THE CWA DURING THE MIDDAY HOURS. IT IS THIS SHORTWAVE THE
FINALLY PUSHES THE POLAR JET CORE SOUTH OF MICHIGAN. THAT WAS
FORECAST TO HAPPEN SOONER BY EARLIER RUNS OF THE MODELS BUT THIS
SHORTWAVE WILL DO THE TRICK AND PUT SOUTHWEST MICHIGAN IN THE DEEP
COLD AIR INTO FRIDAY EVENING. ONCE THE SHORTWAVE IS THROUGH THE
INTENSITY OF THE SNOW SHOWERS WILL DECREASE BUT WE WILL STILL HAVE
LIFT IN THE DGZ WITH NEAR SATURATION DUE OVER ICE THROUGH FRIDAY
AFTERNOON SO THE SNOW SHOWERS WILL CONTINUE INTO FRIDAY AFTERNOON
FOR SURE.
FRIDAY NIGHT INTO SATURDAY THE SURFACE HIGH MOVES IN AND BY MID
MORNING SATURDAY THE AIR BECOMES SO DRY THAT GETTING LAKE EFFECT
CLOUDS WILL HE HARD TO DO...EVEN WITH THE 20C DIFFERENCE BETWEEN
THE LAKE TEMPERATURE AND 850 MB. SO WE SHOULD FINALLY SEE A DRY
PERIOD.
INLAND AREAS TODAY THROUGH FRIDAY WILL SEE OCCASIONAL SNOW SHOWER
WITH THE HELP OF DAY TIME MIXING BRINGING THE SHOWER INLAND. ALSO
THE WEST NORTHWEST WINDS WILL HELP THAT CAUSE TOO.
TEMPERATURES SHOULD LARGELY STAY NEAR TO BELOW FREEZING ALL THREE
AFTERNOONS AND FALL INTO THE 20S AT NIGHT. CLOUDS DUE TO THE WEST
TO NORTHWEST WINDS WILL KEEP IT FROM GETTING MUCH COLDER THAN THAT.
.LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 316 AM EST THU NOV 13 2014
THE COLD SNOWY PATTERN WILL CONTINUE THROUGH THE LONG TERM. HOWEVER
BY LATE WEDNESDAY...MODELS ARE HINTING THAT THE CORE OF THE COLD AIR
WILL START TO LIFT OUT.
THE MAIN FOCUS IS ON MONDAY AND TUESDAY. THAT/S THE TIME FRAME WHEN A
DEEP TROUGH WILL MOVE OVER THE GREAT LAKES AND PRODUCE ANOTHER BLAST
OF ARCTIC AIR. BOTH THE GFS AND ECMWF ARE SIMILAR IN TIMING AND
STRENGTH OF THE UPPER TROUGH. H8 TEMPS FALL TO -16C BY TUESDAY
AFTERNOON. WNW BOUNDARY LAYER WINDS SHOULD RESULT IN LAKE EFFECT
SNOW MONDAY THROUGH TUESDAY. THE DGZ DOES FALL TO AROUND 4K FT...BUT
IS PRETTY TYPICAL FOR THIS TYPE OF COLD AIR. WE/RE LIKELY GOING TO
SEE SEVERAL INCHES OF SNOWFALL DURING THIS TIME FRAME AND WE BOOSTED
POPS TO ACCOUNT FOR IT.
PRIOR TO THE BLAST OF ARCTIC AIR ARRIVING SUNDAY NIGHT...WE/LL SEE
SOME WARM AIR ADVECTION SNOW SATURDAY NIGHT THAT WILL CONTINUE INTO
SUNDAY. ACCUMS IN THE 1-3 INCH RANGE LOOK REASONABLE SATURDAY NIGHT
BASED ON MIXING RATIOS AND THE STRENGTH OF THE ISENTROPIC LIFT.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 622 AM EST THU NOV 13 2014
LAKE EFFECT SNOW SHOWERS WILL PREVAIL THROUGH TOMORROW BUT THE
MORE INTENSE SNOW SHOWERS WILL BE THIS MORNING...NEAR THE LAKE
SHORE (MKG)...POSSIBLY REACHING GRR AND AZO/BTL. LAN AND JXN
SHOULD MOSTLY BE MVFR WITH CIGS AND OCNL SNOW SHOWERS.
THE TAFS ARE WRITTEN TO SHOW MOSTLY VFR CONDITIONS AFTER 18Z BUT I
DO EXPECT THE SNOW BANDS TO MOVE BACK INTO AZO /BTL BY EARLY
EVENING SO I TOOK THEM TO IFR AFTER 02Z. THOSE SNOW BANDS MAY ALSO
IMPACT MKG AND GRR BUT I DID NOT SHOW THAT IN THE TAF FORECAST
SINCE IT SEEMED MORE QUESTIONABLE THEN AT AZO AND BTL.
&&
.MARINE...
ISSUED AT 316 AM EST THU NOV 13 2014
I CONTINUED THE SMALL CRAFT ADVISORY AS IS THROUGH FRIDAY
AFTERNOON. IT WOULD SEEM HIGH PRESSURE BUILDING INTO THE AREA
DURING FRIDAY AFTERNOON SHOULD DECREASE THE PRESSURE GRADIENT AND
ALLOW WINDS AND WAVES TO FINALLY SUBSIDE. UNTIL THEN NORTHWEST
WINDS OF 15 TO 25 KNOTS SHOULD PREVAIL.
&&
.HYDROLOGY...
ISSUED AT 310 PM EST WED NOV 12 2014
NO HYDROLOGY CONCERNS FOR THE NEXT WEEK WITH ANY PCPN OVER THE NEXT
WEEK IN THE FORM OF SNOW AND UNSEASONABLY COLD TEMPS.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...WINTER WEATHER ADVISORY UNTIL 4 PM EST FRIDAY FOR MIZ037-038-043-
056-064-071-072.
LM...SMALL CRAFT ADVISORY UNTIL 4 PM EST FRIDAY FOR LMZ844>849.
&&
$$
SYNOPSIS...WDM
SHORT TERM...WDM
LONG TERM...93
AVIATION...WDM
HYDROLOGY...LAURENS
MARINE...WDM
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
318 AM EST THU NOV 13 2014
LATEST UPDATE...
SYNOPSIS/SHORT TERM/LONG TERM/MARINE
.SYNOPSIS...
ISSUED AT 316 AM EST THU NOV 13 2014
SNOW SHOWERS...LOCALLY HEAVY ARE EXPECTED TODAY SOUTH OF
INTERSTATE 96 AND WEST OF US-131. WHILE THE SNOW SHOWERS WILL
DIMINISH SOME LATE THIS AFTERNOON THEY WILL CONTINUE INTO FRIDAY
AFTERNOON RESULTING IN LOCAL ACCUMULATIONS AS HIGH AS 9 INCHES IN
PARTS OF ALLEGAN AND OTTAWA COUNTIES.
SNOW SHOWERS WILL ALSO RESULT IN 4 TO 6 INCHES OF SNOW WEST OF
US-131 AND NORTH OF MUSKEGON INTO FRIDAY AFTERNOON. ELSEWHERE
LIGHT SNOW SHOWERS WILL CONTINUE INTO FRIDAY WITH AN INCH OR LESS
OF ACCUMULATION.
THE UNSEASONABLY COLD TEMPERATURES...NEAR TO BELOW FREEZING WILL
CONTINUE THROUGH MOST OF NEXT WEEK. THE SNOW SHOWERS SHOULD COME
TO AN END SATURDAY ONLY TO START BACK UP ON SUNDAY AND CONTINUE
INTO WEDNESDAY. A SECOND ARCTIC FRONT WILL BRING EVEN COLDER AIR
IN THE TUESDAY TO WEDNESDAY TIME FRAME.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 316 AM EST THU NOV 13 2014
THE WINTER WEATHER ADVISORY IS OUR PRIMARY FOCUS THIS MORNING. IT
LOOKS VERY GOOD FOR THE HEAVIER SNOWFALL OVER OTTAWA AND ALLEGAN
COUNTIES THIS MORNING BUT IT LOOKS LESS GOOD FOR THE HEAVIER
SNOWFALLS OVER OUR NW CWA EVEN SO... I CONTINUED THE ADVISORY
THERE SINCE THAT IS A TYPICAL PLACE FOR HEAVIER SNOW WITH A WEST
TO NORTHWEST WIND FLOW.
BASED ON THE LATEST DATA FROM OUR HIGH RESOLUTIONS MODELS...
GETTING HEAVIER SNOWFALL AMOUNTS OVER OTTAWA AND ALLEGAN COUNTY
THIS MORNING INTO EARLY THIS AFTERNOON STILL LOOKS GOOD. THE HEAVY
SNOW BANDS ARE FORECAST TO OCCUR FROM MID MORNING INTO EARLY THIS
AFTERNOON OVER ALLEGAN AND OTTAWA COUNTIES BY THE RAP...NAM AND
HRRR MODELS. THE HRRR HAS CONSISTENTLY SHOWN 4 TO 7 INCHES BETWEEN
6 AM AND AND 2 PM THIS AFTERNOON IN TWO BANDS OVER OTTAWA AND
ALLEGAN COUNTIES. THIS IS SIMILAR TO THE OUTPUT OF THE NAMDNG55. SINCE
THE LATEST RADAR IS CURRENTLY SHOWING A SIGNIFICANT INCREASE IN
INTENSITY AND BIV HAS SHOW VISIBILITIES DOWN TO NEAR 1 MILE
ALREADY... I HAVE TO BELIEVE THE LOCALLY HEAVIER SNOW BANDS ARE
MORE THAN POSSIBLE. WHAT ALSO GOES ALONG WITH THIS IS THE LIFT IF
THE DGZ IS IMPRESSIVE ON ALL THREE MODELS OVER THOSE TWO COUNTIES.
THE INVERSION HEIGHTS LIFT TO NEAR 11000 FT BY MID MORNING TOO. ALL
OF THAT HELPS THE CAUSE OF HEAVIER SNOW BANDS IN OUR ADVISORY
AREA.
WHAT IS FORCING ALL OF THIS IS A SIGNIFICANT SHORTWAVE THAT MOVES
THROUGH THE CWA DURING THE MIDDAY HOURS. IT IS THIS SHORTWAVE THE
FINALLY PUSHES THE POLAR JET CORE SOUTH OF MICHIGAN. THAT WAS
FORECAST TO HAPPEN SOONER BY EARLIER RUNS OF THE MODELS BUT THIS
SHORTWAVE WILL DO THE TRICK AND PUT SOUTHWEST MICHIGAN IN THE DEEP
COLD AIR INTO FRIDAY EVENING. ONCE THE SHORTWAVE IS THROUGH THE
INTENSITY OF THE SNOW SHOWERS WILL DECREASE BUT WE WILL STILL HAVE
LIFT IN THE DGZ WITH NEAR SATURATION DUE OVER ICE THROUGH FRIDAY
AFTERNOON SO THE SNOW SHOWERS WILL CONTINUE INTO FRIDAY AFTERNOON
FOR SURE.
FRIDAY NIGHT INTO SATURDAY THE SURFACE HIGH MOVES IN AND BY MID
MORNING SATURDAY THE AIR BECOMES SO DRY THAT GETTING LAKE EFFECT
CLOUDS WILL HE HARD TO DO...EVEN WITH THE 20C DIFFERENCE BETWEEN
THE LAKE TEMPERATURE AND 850 MB. SO WE SHOULD FINALLY SEE A DRY
PERIOD.
INLAND AREAS TODAY THROUGH FRIDAY WILL SEE OCCASIONAL SNOW SHOWER
WITH THE HELP OF DAY TIME MIXING BRINGING THE SHOWER INLAND. ALSO
THE WEST NORTHWEST WINDS WILL HELP THAT CAUSE TOO.
TEMPERATURES SHOULD LARGELY STAY NEAR TO BELOW FREEZING ALL THREE
AFTERNOONS AND FALL INTO THE 20S AT NIGHT. CLOUDS DUE TO THE WEST
TO NORTHWEST WINDS WILL KEEP IT FROM GETTING MUCH COLDER THAN THAT.
.LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 316 AM EST THU NOV 13 2014
THE COLD SNOWY PATTERN WILL CONTINUE THROUGH THE LONG TERM. HOWEVER
BY LATE WEDNESDAY...MODELS ARE HINTING THAT THE CORE OF THE COLD AIR
WILL START TO LIFT OUT.
THE MAIN FOCUS IS ON MONDAY AND TUESDAY. THAT/S THE TIME FRAME WHEN A
DEEP TROUGH WILL MOVE OVER THE GREAT LAKES AND PRODUCE ANOTHER BLAST
OF ARCTIC AIR. BOTH THE GFS AND ECMWF ARE SIMILAR IN TIMING AND
STRENGTH OF THE UPPER TROUGH. H8 TEMPS FALL TO -16C BY TUESDAY
AFTERNOON. WNW BOUNDARY LAYER WINDS SHOULD RESULT IN LAKE EFFECT
SNOW MONDAY THROUGH TUESDAY. THE DGZ DOES FALL TO AROUND 4K FT...BUT
IS PRETTY TYPICAL FOR THIS TYPE OF COLD AIR. WE/RE LIKELY GOING TO
SEE SEVERAL INCHES OF SNOWFALL DURING THIS TIME FRAME AND WE BOOSTED
POPS TO ACCOUNT FOR IT.
PRIOR TO THE BLAST OF ARCTIC AIR ARRIVING SUNDAY NIGHT...WE/LL SEE
SOME WARM AIR ADVECTION SNOW SATURDAY NIGHT THAT WILL CONTINUE INTO
SUNDAY. ACCUMS IN THE 1-3 INCH RANGE LOOK REASONABLE SATURDAY NIGHT
BASED ON MIXING RATIOS AND THE STRENGTH OF THE ISENTROPIC LIFT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1240 AM EST THU NOV 13 2014
SNOW SHOWERS WILL INCREASE IN INTENSITY AND BE MOST NUMEROUS WEST
OF US-131. VISIBILITIES WILL FALL TO 1 1/2-2SM AT KMKG/KAZO/KBTL
THROUGH MID MORNING BEFORE RISING AGAIN AS THE A TROUGH MOVES
THROUGH. SHSN WILL DIMINISH LATER THIS AFTERNOON.
&&
.MARINE...
ISSUED AT 316 AM EST THU NOV 13 2014
I CONTINUED THE SMALL CRAFT ADVISORY AS IS THROUGH FRIDAY
AFTERNOON. IT WOULD SEEM HIGH PRESSURE BUILDING INTO THE AREA
DURING FRIDAY AFTERNOON SHOULD DECREASE THE PRESSURE GRADIENT AND
ALLOW WINDS AND WAVES TO FINALLY SUBSIDE. UNTIL THEN NORTHWEST
WINDS OF 15 TO 25 KNOTS SHOULD PREVAIL.
&&
.HYDROLOGY...
ISSUED AT 310 PM EST WED NOV 12 2014
NO HYDROLOGY CONCERNS FOR THE NEXT WEEK WITH ANY PCPN OVER THE NEXT
WEEK IN THE FORM OF SNOW AND UNSEASONABLY COLD TEMPS.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...WINTER WEATHER ADVISORY UNTIL 4 PM EST FRIDAY FOR MIZ037-038-043-
056-064-071-072.
LM...SMALL CRAFT ADVISORY UNTIL 4 PM EST FRIDAY FOR LMZ844>849.
&&
$$
SYNOPSIS...WDM
SHORT TERM...WDM
LONG TERM...93
AVIATION...93
HYDROLOGY...LAURENS
MARINE...WDM
AREA FORECAST DISCUSSION
NWS JACKSON MS
1010 AM CST THU NOV 13 2014
.UPDATE...A RATHER CHILLY MORNING WAS STILL BEING OBSERVED OVER THE
ARKLAMISS AS 10AM TEMPERATURES WERE STILL IN THE 30S AND A GUSTY
NORTH WIND CHILL TEMPERATURES BELOW FREEZING. SPLIT FLOW REGIME WITH
NORTHERN STREAM SHORTWAVE AND A SOUTHERN STREAM SHORTWAVE MOVING
ACROSS OUR CWA WAS RESULTING IN VERY LIT RAIN OVER PORTIONS OF THE
CWA. THE NORTHERN STREAM SHORTWAVE IS ALMOST EAST OF OUR CWA AND A
VERY NARROW BAND OF MOSTLY SPRINKLES HAS SHIFTED EAST OF GRANADA.
EARLIER THIS MORNING A REPORT OF LIGHT SLEET MIXED WITH THE RAIN WAS
NOTED IN NORTHERN BOLIVAR COUNTY WITH THIS BAND BUT NO IMPACTS
OCCURRED DUE TO THE BRIEF DURATION AND VERY LIGHT AMOUNTS. IN THE
SOUTH THE SOUTHERN STREAM SHORTWAVE WAS STILL HELPING PRODUCE A BAND
OF LIGHT RAIN ALONG THE HIGHWAY 84 CORRIDOR. THIS BAND OF RAIN WILL
SHIFT EAST AND END OVER OUR CWA AS THE SHORTWAVE SHIFTS EAST AS
WELL. CLOUD COVER SHOULD BREAK UP THIS AFTERNOON AND ALLOW SOME
SUNSHINE THROUGH. THIS WILL AID TEMPERATURES IN RISING INTO THE 40S.
HAVE ADJUSTED CLOUD COVER AND DEW POINTS THIS WITH THE UPDATE BUT
THE REMAINDER OF THE FORECAST IS ON TRACK. /22/
&&
.AVIATION...A MIX OF MVFR/VFR CONDITIONS WILL PREVAIL ACROSS THE
ARKLAMISS THIS MORNING INTO THE AFTERNOON HOURS. A FEW VERY LIGHT
RAINSHOWERS ARE POSSIBLE AT HBG THIS MORNING ALSO. EXPECT ALL SITES
TO BECOME VFR AFTER 19-20Z WITH MAINLY CLEAR SKIES AFTER 14/00Z. THE
WINDS WILL BE OUT OF THE NORTH AT 6-10KTS WITH GUSTS FROM 15-20KTS
AT GLH/GWO BECOMING 4-8KTS OUT OF THE NORTH OVERNIGHT./15/
&&
.PREV DISCUSSION... /ISSUED 402 AM CST THU NOV 13 2014/
SHORT TERM...TODAY THROUGH FRIDAY NIGHT...LOW CLOUDS CONTINUE TO
PUSH OFF TO THE EAST AS THE COLD/DRY AIR STEADILY BUILDS INTO THE
REGION. MEANWHILE...MID/HIGH CLOUDS ARE ON THE INCREASE AS SHORTWAVE
MOVING THROUGH THE BASE OF H5 TROF HAS TAPPED AVAILABLE MOISTURE OVER
THE NORTHERN GULF OF MEXICO. ALREADY...ISENTROPIC LIFT HAS ALLOWED
AREA OF RAIN TO BREAK OUT ALONG THE LA COAST...BUT THE MAJORITY DOES
NOT APPEAR TO BE REACHING THE GROUND. HRRR IS ALSO INDICATING WINTRY
PRECIP OVER ARKANSAS...BUT THIS AREA SHOULD JUST GRAZE OUR EXTREME
NORTHERN AREAS EARLY AS IT RAPIDLY HEADS EAST.
THE SLUG OF MOISTURE AND LIFT FROM THE NORTHERN GULF WILL MAINLY
AFFECT SOUTH MS THIS MORNING AND QUICKLY PULL EAST ALONG WITH THE
CLOUD COVER THIS AFTERNOON. WOULD NOT BE SURPRISED TO HEAR OF A FEW
ICE PELLETS MIXED IN WITH THE LIGHT RAIN ON THE NORTHERN FRINGES
GIVEN DRY/COLD AIR IN THE COLUMN AS INDICATED IN THE BUFR DATA
PROFILES.
WITH THE DRY AIR IN PLACE...EXPECT DECOUPLING AND STRONG RADIATIVE
COOLING TO BEGIN AFTER SUNSET ALLOWING TEMPS TO DROP RAPIDLY. WILL
UPGRADE THE FREEZE WATCH TO A WARNING AS EXPECT MID 20S TO BE
WIDESPREAD ACROSS THE FORECAST AREA BY EARLY FRIDAY MORNING. THIS
FREEZE SHOULD KILL ANY REMAINING LIVE VEGETATION.
TEMPS WILL BE SLOW TO MODERATE MUCH IF ANY FRIDAY AS NORTHERLY WINDS
CONTINUE TO USHER THE COOL AIR SOUTHWARD. TWENTIES LOOK LIKE A GOOD
BET AGAIN FRIDAY NIGHT...SLIGHTLY WARMER UPPER 20S OVER THE SOUTH
AND WEST AS SURFACE HIGH PRESSURE PUSHES EAST AND WINDS SWITCH TO
THE SOUTH./26/
LONG TERM...SATURDAY THROUGH NEXT THURSDAY...THE TWO MAIN STORIES
OF THIS PERIOD WILL BE THE WIDESPREAD RAIN EXPECTED SUNDAY INTO EARLY
MONDAY AND THE SUBSTANTIAL COLD TEMPERATURES THAT WILL FOLLOW EARLY
TO MID-NEXT WEEK. 1) RAIN TOTALS WILL RANGE FROM 1-2 INCHES AND SOME
LOCALLY HIGHER AMOUNTS NEAR 3 INCHES COULD BE POSSIBLE. 2)
TEMPERATURES WILL PLUNGE MID-WEEK WITH SEVERAL HARD FREEZES LIKELY
INTO THE LOW AND MID 20S.
OVERALL MODEL ENVELOPE HAS GOOD SYNOPTIC PATTERN AGREEMENT THROUGH
PERIOD INDICATING A STRONG BAROCLINIC ZONE ALONG THE NORTHERN GULF
INTERACTING WITH SEVERAL EMBEDDED H5 S/WV TROUGHS THAT WILL EJECT
OUT AHEAD OF A MORE POTENT PACIFIC ORIGINATED LONGWAVE TROUGH BY
SUNDAY INTO EARLY MONDAY. SURFACE LOW CYCLOGENESIS SHOULD OCCUR
ALONG THE BAROCLINIC ZONE AND COUPLED WITH UPPER DIVERGENCE FROM
INCREASING FRONT ENTRANCE JET MAGNITUDE WILL AID IN LARGE RAIN
SHIELD SUNDAY INTO EARLY MONDAY. THIS PACIFIC TROUGH SHOULD THEN
PHASE WITH A POLAR ORIGINATED TROUGH LATE MONDAY INTO TUESDAY THAT
WILL USHER -3 TO -4 SD H925 TEMPS OVER THE REGION. THIS WILL LEAD TO
SEVERAL HARD FREEZES WITH WIDESPREAD LOW TEMPERATURES OF MID 20S AND
HIGHS MAINLY IN THE 40S.
FOR SENSIBLE WEATHER DETAILS, RAIN CHANCES WERE BOOSTED SUNDAY AND
OVERNIGHT INTO EARLY MONDAY WITH A CONTINUED SLOWING TREND WITH HIGH
CONFIDENCE OF RAIN. EXPECT A COLD RAIN SUNDAY INTO EARLY MONDAY WITH
HEAVIEST RAIN ALONG AND SOUTH OF NATCHEZ TRACE CORRIDOR. INTRODUCED
SLIGHT CHANCE THUNDER AS SLIGHTLY NEGATIVE SHOWALTERS AND HIGHER
VERTICAL TOTALS (25C) WILL BE INVOF DIRECT CIRCULATION AND JET
INDUCED DIVERGENCE THAT WILL ACT TO INCREASE RAINFALL RATE POCKETS.
MODELS ARE NOT AS STRONG ON SURFACE LOW DEVELOPMENT VS. PREVIOUS
RUNS AND THUS COLD AIR DOES NOT LOOK TO FILTER IN FAST ENOUGH ON
BACKSIDE FOR ANY WINTER PRECIP CHANGEOVER. HAVE KEPT OUT ANY WINTER
MIX AT THIS POINT.
FROM MONDAY THROUGH WEDNESDAY, BOTH MAX HIGHS AND MIN LOWS WERE
DROPPED 2-4F DEGREES TO BE MORE IN LINE WITH RAW MODEL GUIDANCE.
NEXT TUESDAY LOOKS QUITE COLD AS LOWS SHOULD FALL INTO THE LOW TO
MID 20S WITH AFTERNOON TEMPS ONLY RECOVERING INTO MID/UPPER 30S
NORTH TO NEAR 40S SOUTH. WIND CHILLS COULD FALL INTO THE TEENS
TUESDAY MORNING AND NOT FULLY RECOVER ABOVE FREEZING THROUGH THE
DAY. A SLOW WARMING PATTERN SHOULD OCCUR GOING INTO LATE WEEK BUT
TEMPS WILL REMAIN BELOW NORMAL. /ALLEN/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 44 25 45 27 / 12 2 5 3
MERIDIAN 46 23 47 26 / 13 2 4 3
VICKSBURG 43 24 45 27 / 11 2 3 3
HATTIESBURG 44 25 48 27 / 25 2 4 3
NATCHEZ 41 23 45 28 / 17 2 4 3
GREENVILLE 41 24 41 27 / 8 1 3 3
GREENWOOD 41 22 42 25 / 8 2 3 3
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...FREEZE WARNING FROM 11 PM THIS EVENING TO 8 AM CST FRIDAY FOR
MSZ018-019-025>066-072>074.
LA...FREEZE WARNING FROM 11 PM THIS EVENING TO 8 AM CST FRIDAY FOR
LAZ007>009-015-016-023>026.
AR...FREEZE WARNING FROM 11 PM THIS EVENING TO 8 AM CST FRIDAY FOR
ARZ074-075.
&&
$$
22/15/26/ALLEN
AREA FORECAST DISCUSSION
NWS JACKSON MS
402 AM CST THU NOV 13 2014
.SHORT TERM...TODAY THROUGH FRIDAY NIGHT...LOW CLOUDS CONTINUE TO
PUSH OFF TO THE EAST AS THE COLD/DRY AIR STEADILY BUILDS INTO THE
REGION. MEANWHILE...MID/HIGH CLOUDS ARE ON THE INCREASE AS SHORTWAVE
MOVING THROUGH THE BASE OF H5 TROF HAS TAPPED AVAILABLE MOISTURE OVER
THE NORTHERN GULF OF MEXICO. ALREADY...ISENTROPIC LIFT HAS ALLOWED
AREA OF RAIN TO BREAK OUT ALONG THE LA COAST...BUT THE MAJORITY DOES
NOT APPEAR TO BE REACHING THE GROUND. HRRR IS ALSO INDICATING WINTRY
PRECIP OVER ARKANSAS...BUT THIS AREA SHOULD JUST GRAZE OUR EXTREME
NORTHERN AREAS EARLY AS IT RAPIDLY HEADS EAST.
THE SLUG OF MOISTURE AND LIFT FROM THE NORTHERN GULF WILL MAINLY
AFFECT SOUTH MS THIS MORNING AND QUICKLY PULL EAST ALONG WITH THE
CLOUD COVER THIS AFTERNOON. WOULD NOT BE SURPRISED TO HEAR OF A FEW
ICE PELLETS MIXED IN WITH THE LIGHT RAIN ON THE NORTHERN FRINGES
GIVEN DRY/COLD AIR IN THE COLUMN AS INDICATED IN THE BUFR DATA
PROFILES.
WITH THE DRY AIR IN PLACE...EXPECT DECOUPLING AND STRONG RADIATIVE
COOLING TO BEGIN AFTER SUNSET ALLOWING TEMPS TO DROP RAPIDLY. WILL
UPGRADE THE FREEZE WATCH TO A WARNING AS EXPECT MID 20S TO BE
WIDESPREAD ACROSS THE FORECAST AREA BY EARLY FRIDAY MORNING. THIS
FREEZE SHOULD KILL ANY REMAINING LIVE VEGETATION.
TEMPS WILL BE SLOW TO MODERATE MUCH IF ANY FRIDAY AS NORTHERLY WINDS
CONTINUE TO USHER THE COOL AIR SOUTHWARD. TWENTIES LOOK LIKE A GOOD
BET AGAIN FRIDAY NIGHT...SLIGHTLY WARMER UPPER 20S OVER THE SOUTH
AND WEST AS SURFACE HIGH PRESSURE PUSHES EAST AND WINDS SWITCH TO
THE SOUTH./26/
.LONG TERM...SATURDAY THROUGH NEXT THURSDAY...THE TWO MAIN STORIES
OF THIS PERIOD WILL BE THE WIDESPREAD RAIN EXPECTED SUNDAY INTO EARLY
MONDAY AND THE SUBSTANTIAL COLD TEMPERATURES THAT WILL FOLLOW EARLY
TO MID-NEXT WEEK. 1) RAIN TOTALS WILL RANGE FROM 1-2 INCHES AND SOME
LOCALLY HIGHER AMOUNTS NEAR 3 INCHES COULD BE POSSIBLE. 2)
TEMPERATURES WILL PLUNGE MID-WEEK WITH SEVERAL HARD FREEZES LIKELY
INTO THE LOW AND MID 20S.
OVERALL MODEL ENVELOPE HAS GOOD SYNOPTIC PATTERN AGREEMENT THROUGH
PERIOD INDICATING A STRONG BAROCLINIC ZONE ALONG THE NORTHERN GULF
INTERACTING WITH SEVERAL EMBEDDED H5 S/WV TROUGHS THAT WILL EJECT
OUT AHEAD OF A MORE POTENT PACIFIC ORIGINATED LONGWAVE TROUGH BY
SUNDAY INTO EARLY MONDAY. SURFACE LOW CYCLOGENESIS SHOULD OCCUR
ALONG THE BAROCLINIC ZONE AND COUPLED WITH UPPER DIVERGENCE FROM
INCREASING FRONT ENTRANCE JET MAGNITUDE WILL AID IN LARGE RAIN
SHIELD SUNDAY INTO EARLY MONDAY. THIS PACIFIC TROUGH SHOULD THEN
PHASE WITH A POLAR ORIGINATED TROUGH LATE MONDAY INTO TUESDAY THAT
WILL USHER -3 TO -4 SD H925 TEMPS OVER THE REGION. THIS WILL LEAD TO
SEVERAL HARD FREEZES WITH WIDESPREAD LOW TEMPERATURES OF MID 20S AND
HIGHS MAINLY IN THE 40S.
FOR SENSIBLE WEATHER DETAILS, RAIN CHANCES WERE BOOSTED SUNDAY AND
OVERNIGHT INTO EARLY MONDAY WITH A CONTINUED SLOWING TREND WITH HIGH
CONFIDENCE OF RAIN. EXPECT A COLD RAIN SUNDAY INTO EARLY MONDAY WITH
HEAVIEST RAIN ALONG AND SOUTH OF NATCHEZ TRACE CORRIDOR. INTRODUCED
SLIGHT CHANCE THUNDER AS SLIGHTLY NEGATIVE SHOWALTERS AND HIGHER
VERTICAL TOTALS (25C) WILL BE INVOF DIRECT CIRCULATION AND JET
INDUCED DIVERGENCE THAT WILL ACT TO INCREASE RAINFALL RATE POCKETS.
MODELS ARE NOT AS STRONG ON SURFACE LOW DEVELOPMENT VS. PREVIOUS
RUNS AND THUS COLD AIR DOES NOT LOOK TO FILTER IN FAST ENOUGH ON
BACKSIDE FOR ANY WINTER PRECIP CHANGEOVER. HAVE KEPT OUT ANY WINTER
MIX AT THIS POINT.
FROM MONDAY THROUGH WEDNESDAY, BOTH MAX HIGHS AND MIN LOWS WERE
DROPPED 2-4F DEGREES TO BE MORE IN LINE WITH RAW MODEL GUIDANCE.
NEXT TUESDAY LOOKS QUITE COLD AS LOWS SHOULD FALL INTO THE LOW TO
MID 20S WITH AFTERNOON TEMPS ONLY RECOVERING INTO MID/UPPER 30S
NORTH TO NEAR 40S SOUTH. WIND CHILLS COULD FALL INTO THE TEENS
TUESDAY MORNING AND NOT FULLY RECOVER ABOVE FREEZING THROUGH THE
DAY. A SLOW WARMING PATTERN SHOULD OCCUR GOING INTO LATE WEEK BUT
TEMPS WILL REMAIN BELOW NORMAL. /ALLEN/
&&
.AVIATION...THOUGH MID/HIGH LEVEL CEILINGS WILL EXIST FOR THE
MAJORITY OF THE PERIOD...VFR CONDITIONS WILL PREVAIL. AREAS OF RAIN
WILL BE POSSIBLE IN THE HBG VICINITY TODAY...BUT SHOULD NOT BE HEAVY
ENOUGH TO CREATE ANY OBSTRUCTION TO VISIBILITY. SKIES WILL CLEAR
AFTER 14/00Z./26/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 44 25 45 27 / 12 2 5 3
MERIDIAN 46 23 47 26 / 13 2 4 3
VICKSBURG 43 24 45 27 / 11 2 3 3
HATTIESBURG 44 25 48 27 / 25 2 4 3
NATCHEZ 41 23 45 28 / 17 2 4 3
GREENVILLE 41 24 41 27 / 8 1 3 3
GREENWOOD 41 22 42 25 / 8 2 3 3
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...FREEZE WARNING FROM 11 PM THIS EVENING TO 8 AM CST FRIDAY FOR
MSZ018-019-025>066-072>074.
LA...FREEZE WARNING FROM 11 PM THIS EVENING TO 8 AM CST FRIDAY FOR
LAZ007>009-015-016-023>026.
AR...FREEZE WARNING FROM 11 PM THIS EVENING TO 8 AM CST FRIDAY FOR
ARZ074-075.
&&
$$
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1228 PM CST THU NOV 13 2014
.UPDATE...
ISSUED AT 1225 PM CST THU NOV 13 2014
AREAS OF LOW STRATUS REMAIN OVER THE AREA WITH SOME FLURRIES
CONTINUING. FOR EARLY AFTERNOON UPDATE HAVE EXTENDED THE TIMING OF
THE CLOUD COVER...ERODING IT OUT LATER THIS AFTERNOON INTO THE
EVENING.
UPDATE ISSUED AT 844 AM CST THU NOV 13 2014
BROAD AREA OF STATUS REMAINS OVER MUCH OF WESTERN INTO CENTRAL
NORTH DAKOTA WHICH MODELS ARE STILL HAVING TROUBLE WITH. WILL KEEP
CLOUDS IN PLACE THROUGH MID-DAY BEFORE STARTING TO ERODE OUT. HAVE
ADDED MENTION OF FLURRIES UNDER THE CLOUD COVER THROUGH MID-DAY AS
VARIOUS POINTS ARE REPORTING SNOW...BUT LITTLE TO NO REDUCTION IN
VISIBILITIES. UPDATES HAVE BEEN SENT.
UPDATE ISSUED AT 607 AM CST THU NOV 13 2014
THE 06 UTC DETERMINISTIC SUITE AND 09-11 UTC RAP/HRRR ITERATIONS
ARE HAVING A DIFFICULT TIME RESOLVING THE LOW LEVEL STRATUS FIELD
THAT CONTINUES TO SLOWLY EXPAND ACROSS WESTERN AND CENTRAL NORTH
DAKOTA THIS MORNING. THE 10 UTC LAMP IS REALLY THE ONLY GUIDANCE
PICKING UP ON THE STRATUS. THUS...WILL MAINTAIN THE STRATUS AS
OBSERVED THROUGH 12 UTC...SLOWLY ERODING IT THROUGH THE AFTERNOON
AS THE SURFACE HIGH AXIS ACROSS EASTERN MONTANA PROPAGATES EAST.
HOWEVER...CONFIDENCE IN HOW THE STRATUS WILL EVOLVE IS LOW. ALSO
ADDED FLURRIES TO LOCATIONS UNDER THE STRATUS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 314 AM CST THU NOV 13 2014
CLOUDS CONTINUE TO INCREASE ACROSS THE AREA THIS MORNING. THIS IS
ALLOWING TEMPERATURES TO MODERATE SOMEWHAT ACROSS THE REGION THIS
MORNING. CLOUDS ARE EXPECTED TO THIN OUT THROUGH THE DAY.
VERY HIGH PRESSURE WILL CONTINUE TO SETTLE ACROSS THE AREA TODAY.
HIGH TEMPERATURES TODAY WILL ONLY RISE INTO THE LOW TEENS. TONIGHT
THE RAP IS FORECASTING A 1042 MB HIGH ACROSS SOUTHWEST NORTH
DAKOTA. THIS IS RATHER ANOMALOUS ANYTIME DURING WINTER...BUT
ESPECIALLY THIS EARLY. THIS VERY COLD HIGH PRESSURE CENTER WILL
AID IN TEMPERATURES FALLING INTO THE TEENS BELOW ZERO ACROSS THE
SOUTHWEST. COMBINE A LIGHT WIND WITH THESE TEMPERATURES AND YOU
HAVE WIND CHILL READINGS IN THE 20S BELOW ZERO. THIS WILL LIKELY
WARRANT A WIND CHILL HEADLINE.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 314 AM CST THU NOV 13 2014
CONTINUED COLD THROUGH THE PERIOD AND BLOWING SNOW POTENTIAL
SUNDAY HIGHLIGHT THE EXTENDED FORECAST.
THE 00 UTC GUIDANCE SUITE CONTINUES TO DEPICT A BLOCKING HIGH
AMPLITUDE UPPER LEVEL RIDGE ACROSS THE EASTERN PACIFIC AND AN
ANOMALOUSLY DEEP LONG WAVE TROUGH ACROSS THE CENTRAL AND EASTERN
CONUS REMAINING THROUGH THE EXTENDED. THIS PATTERNS PROPAGATES
VERY SLOWLY EAST THROUGH THE PERIOD...WHICH MAY ALLOW FOR A
RELATIVE WARM UP INTO STILL BELOW NORMAL HIGHS IN THE 20S BY MID
NEXT WEEK. PRIOR TO THIS...HIGHS GENERALLY IN THE TEENS ARE
EXPECTED WITH WIND CHILLS EACH NIGHT AND EARLY MORNING APPROACHING
BUT STAYING JUST WARMER THAN ADVISORY CRITERIA OF -25. THE 00 UTC
SUITE IS ALSO IN AGREEMENT ON A CLIPPER SYSTEM TO IMPACT THE
NORTHERN PLAINS ON SUNDAY. STRONG WINDS BEHIND THE REINFORCING
COLD SURGE MAY LEAD TO BLOWING SNOW...ESPECIALLY ACROSS THE
SOUTHWEST AND SOUTH CENTRAL WHERE SNOW DEPTHS ARE GREATEST.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1225 PM CST THU NOV 13 2014
AREAS OF MVFR CIGS WILL CONTINUE OVER WESTERN AND CENTRAL NORTH
DAKOTA THROUGH MID-AFTERNOON. CIGS ARE THEN EXPECTED TO IMPROVE TO
VFR THROUGH THE LATE AFTERNOON/EARLY EVENING...AND WILL REMAIN VFR
THROUGH THE REMAINDER OF THE FORECAST PERIOD.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JJS
SHORT TERM...AJ
LONG TERM...AYD
AVIATION...JJS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
853 AM CST THU NOV 13 2014
.UPDATE...
ISSUED AT 844 AM CST THU NOV 13 2014
BROAD AREA OF STATUS REMAINS OVER MUCH OF WESTERN INTO CENTRAL
NORTH DAKOTA WHICH MODELS ARE STILL HAVING TROUBLE WITH. WILL KEEP
CLOUDS IN PLACE THROUGH MID-DAY BEFORE STARTING TO ERODE OUT. HAVE
ADDED MENTION OF FLURRIES UNDER THE CLOUD COVER THROUGH MID-DAY AS
VARIOUS POINTS ARE REPORTING SNOW...BUT LITTLE TO NO REDUCTION IN
VISIBILITIES. UPDATES HAVE BEEN SENT.
UPDATE ISSUED AT 607 AM CST THU NOV 13 2014
THE 06 UTC DETERMINISTIC SUITE AND 09-11 UTC RAP/HRRR ITERATIONS
ARE HAVING A DIFFICULT TIME RESOLVING THE LOW LEVEL STRATUS FIELD
THAT CONTINUES TO SLOWLY EXPAND ACROSS WESTERN AND CENTRAL NORTH
DAKOTA THIS MORNING. THE 10 UTC LAMP IS REALLY THE ONLY GUIDANCE
PICKING UP ON THE STRATUS. THUS...WILL MAINTAIN THE STRATUS AS
OBSERVED THROUGH 12 UTC...SLOWLY ERODING IT THROUGH THE AFTERNOON
AS THE SURFACE HIGH AXIS ACROSS EASTERN MONTANA PROPAGATES EAST.
HOWEVER...CONFIDENCE IN HOW THE STRATUS WILL EVOLVE IS LOW. ALSO
ADDED FLURRIES TO LOCATIONS UNDER THE STRATUS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 314 AM CST THU NOV 13 2014
CLOUDS CONTINUE TO INCREASE ACROSS THE AREA THIS MORNING. THIS IS
ALLOWING TEMPERATURES TO MODERATE SOMEWHAT ACROSS THE REGION THIS
MORNING. CLOUDS ARE EXPECTED TO THIN OUT THROUGH THE DAY.
VERY HIGH PRESSURE WILL CONTINUE TO SETTLE ACROSS THE AREA TODAY.
HIGH TEMPERATURES TODAY WILL ONLY RISE INTO THE LOW TEENS. TONIGHT
THE RAP IS FORECASTING A 1042 MB HIGH ACROSS SOUTHWEST NORTH
DAKOTA. THIS IS RATHER ANOMALOUS ANYTIME DURING WINTER...BUT
ESPECIALLY THIS EARLY. THIS VERY COLD HIGH PRESSURE CENTER WILL
AID IN TEMPERATURES FALLING INTO THE TEENS BELOW ZERO ACROSS THE
SOUTHWEST. COMBINE A LIGHT WIND WITH THESE TEMPERATURES AND YOU
HAVE WIND CHILL READINGS IN THE 20S BELOW ZERO. THIS WILL LIKELY
WARRANT A WIND CHILL HEADLINE.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 314 AM CST THU NOV 13 2014
CONTINUED COLD THROUGH THE PERIOD AND BLOWING SNOW POTENTIAL
SUNDAY HIGHLIGHT THE EXTENDED FORECAST.
THE 00 UTC GUIDANCE SUITE CONTINUES TO DEPICT A BLOCKING HIGH
AMPLITUDE UPPER LEVEL RIDGE ACROSS THE EASTERN PACIFIC AND AN
ANOMALOUSLY DEEP LONG WAVE TROUGH ACROSS THE CENTRAL AND EASTERN
CONUS REMAINING THROUGH THE EXTENDED. THIS PATTERNS PROPAGATES
VERY SLOWLY EAST THROUGH THE PERIOD...WHICH MAY ALLOW FOR A
RELATIVE WARM UP INTO STILL BELOW NORMAL HIGHS IN THE 20S BY MID
NEXT WEEK. PRIOR TO THIS...HIGHS GENERALLY IN THE TEENS ARE
EXPECTED WITH WIND CHILLS EACH NIGHT AND EARLY MORNING APPROACHING
BUT STAYING JUST WARMER THAN ADVISORY CRITERIA OF -25. THE 00 UTC
SUITE IS ALSO IN AGREEMENT ON A CLIPPER SYSTEM TO IMPACT THE
NORTHERN PLAINS ON SUNDAY. STRONG WINDS BEHIND THE REINFORCING
COLD SURGE MAY LEAD TO BLOWING SNOW...ESPECIALLY ACROSS THE
SOUTHWEST AND SOUTH CENTRAL WHERE SNOW DEPTHS ARE GREATEST.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 607 AM CST THU NOV 13 2014
MVFR STRATUS WITH EMBEDDED POCKETS OF BRIEF IFR VISIBILITIES IN
LIGHT SNOW WILL IMPACT MUCH OF WESTERN AND CENTRAL NORTH DAKOTA
THIS MORNING. WHILE THE STRATUS IS EXPECTED TO SLOWLY DECREASE
INTO THE AFTERNOON...CONFIDENCE IN THE TIMING OF CLEARING IS LOW.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JJS
SHORT TERM...AJ
LONG TERM...AYD
AVIATION...AYD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
607 AM CST THU NOV 13 2014
.UPDATE...
ISSUED AT 607 AM CST THU NOV 13 2014
THE 06 UTC DETERMINISTIC SUITE AND 09-11 UTC RAP/HRRR ITERATIONS
ARE HAVING A DIFFICULT TIME RESOLVING THE LOW LEVEL STRATUS FIELD
THAT CONTINUES TO SLOWLY EXPAND ACROSS WESTERN AND CENTRAL NORTH
DAKOTA THIS MORNING. THE 10 UTC LAMP IS REALLY THE ONLY GUIDANCE
PICKING UP ON THE STRATUS. THUS...WILL MAINTAIN THE STRATUS AS
OBSERVED THROUGH 12 UTC...SLOWLY ERODING IT THROUGH THE AFTERNOON
AS THE SURFACE HIGH AXIS ACROSS EASTERN MONTANA PROPAGATES EAST.
HOWEVER...CONFIDENCE IN HOW THE STRATUS WILL EVOLVE IS LOW. ALSO
ADDED FLURRIES TO LOCATIONS UNDER THE STRATUS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 314 AM CST THU NOV 13 2014
CLOUDS CONTINUE TO INCREASE ACROSS THE AREA THIS MORNING. THIS IS
ALLOWING TEMPERATURES TO MODERATE SOMEWHAT ACROSS THE REGION THIS
MORNING. CLOUDS ARE EXPECTED TO THIN OUT THROUGH THE DAY.
VERY HIGH PRESSURE WILL CONTINUE TO SETTLE ACROSS THE AREA TODAY.
HIGH TEMPERATURES TODAY WILL ONLY RISE INTO THE LOW TEENS. TONIGHT
THE RAP IS FORECASTING A 1042 MB HIGH ACROSS SOUTHWEST NORTH
DAKOTA. THIS IS RATHER ANOMALOUS ANYTIME DURING WINTER...BUT
ESPECIALLY THIS EARLY. THIS VERY COLD HIGH PRESSURE CENTER WILL
AID IN TEMPERATURES FALLING INTO THE TEENS BELOW ZERO ACROSS THE
SOUTHWEST. COMBINE A LIGHT WIND WITH THESE TEMPERATURES AND YOU
HAVE WIND CHILL READINGS IN THE 20S BELOW ZERO. THIS WILL LIKELY
WARRANT A WIND CHILL HEADLINE.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 314 AM CST THU NOV 13 2014
CONTINUED COLD THROUGH THE PERIOD AND BLOWING SNOW POTENTIAL
SUNDAY HIGHLIGHT THE EXTENDED FORECAST.
THE 00 UTC GUIDANCE SUITE CONTINUES TO DEPICT A BLOCKING HIGH
AMPLITUDE UPPER LEVEL RIDGE ACROSS THE EASTERN PACIFIC AND AN
ANOMALOUSLY DEEP LONG WAVE TROUGH ACROSS THE CENTRAL AND EASTERN
CONUS REMAINING THROUGH THE EXTENDED. THIS PATTERNS PROPAGATES
VERY SLOWLY EAST THROUGH THE PERIOD...WHICH MAY ALLOW FOR A
RELATIVE WARM UP INTO STILL BELOW NORMAL HIGHS IN THE 20S BY MID
NEXT WEEK. PRIOR TO THIS...HIGHS GENERALLY IN THE TEENS ARE
EXPECTED WITH WIND CHILLS EACH NIGHT AND EARLY MORNING APPROACHING
BUT STAYING JUST WARMER THAN ADVISORY CRITERIA OF -25. THE 00 UTC
SUITE IS ALSO IN AGREEMENT ON A CLIPPER SYSTEM TO IMPACT THE
NORTHERN PLAINS ON SUNDAY. STRONG WINDS BEHIND THE REINFORCING
COLD SURGE MAY LEAD TO BLOWING SNOW...ESPECIALLY ACROSS THE
SOUTHWEST AND SOUTH CENTRAL WHERE SNOW DEPTHS ARE GREATEST.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 607 AM CST THU NOV 13 2014
MVFR STRATUS WITH EMBEDDED POCKETS OF BRIEF IFR VISIBILITIES IN
LIGHT SNOW WILL IMPACT MUCH OF WESTERN AND CENTRAL NORTH DAKOTA
THIS MORNING. WHILE THE STRATUS IS EXPECTED TO SLOWLY DECREASE
INTO THE AFTERNOON...CONFIDENCE IN THE TIMING OF CLEARING IS LOW.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AYD
SHORT TERM...AJ
LONG TERM...AYD
AVIATION...AYD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
314 AM CST THU NOV 13 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 314 AM CST THU NOV 13 2014
CLOUDS CONTINUE TO INCREASE ACROSS THE AREA THIS MORNING. THIS IS
ALLOWING TEMPERATURES TO MODERATE SOMEWHAT ACROSS THE REGION THIS
MORNING. CLOUDS ARE EXPECTED TO THIN OUT THROUGH THE DAY.
VERY HIGH PRESSURE WILL CONTINUE TO SETTLE ACROSS THE AREA TODAY.
HIGH TEMPERATURES TODAY WILL ONLY RISE INTO THE LOW TEENS. TONIGHT
THE RAP IS FORECASTING A 1042 MB HIGH ACROSS SOUTHWEST NORTH
DAKOTA. THIS IS RATHER ANOMALOUS ANYTIME DURING WINTER...BUT
ESPECIALLY THIS EARLY. THIS VERY COLD HIGH PRESSURE CENTER WILL
AID IN TEMPERATURES FALLING INTO THE TEENS BELOW ZERO ACROSS THE
SOUTHWEST. COMBINE A LIGHT WIND WITH THESE TEMPERATURES AND YOU
HAVE WIND CHILL READINGS IN THE 20S BELOW ZERO. THIS WILL LIKELY
WARRANT A WIND CHILL HEADLINE.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 314 AM CST THU NOV 13 2014
CONTINUED COLD THROUGH THE PERIOD AND BLOWING SNOW POTENTIAL
SUNDAY HIGHLIGHT THE EXTENDED FORECAST.
THE 00 UTC GUIDANCE SUITE CONTINUES TO DEPICT A BLOCKING HIGH
AMPLITUDE UPPER LEVEL RIDGE ACROSS THE EASTERN PACIFIC AND AN
ANOMALOUSLY DEEP LONG WAVE TROUGH ACROSS THE CENTRAL AND EASTERN
CONUS REMAINING THROUGH THE EXTENDED. THIS PATTERNS PROPAGATES
VERY SLOWLY EAST THROUGH THE PERIOD...WHICH MAY ALLOW FOR A
RELATIVE WARM UP INTO STILL BELOW NORMAL HIGHS IN THE 20S BY MID
NEXT WEEK. PRIOR TO THIS...HIGHS GENERALLY IN THE TEENS ARE
EXPECTED WITH WIND CHILLS EACH NIGHT AND EARLY MORNING APPROACHING
BUT STAYING JUST WARMER THAN ADVISORY CRITERIA OF -25. THE 00 UTC
SUITE IS ALSO IN AGREEMENT ON A CLIPPER SYSTEM TO IMPACT THE
NORTHERN PLAINS ON SUNDAY. STRONG WINDS BEHIND THE REINFORCING
COLD SURGE MAY LEAD TO BLOWING SNOW...ESPECIALLY ACROSS THE
SOUTHWEST AND SOUTH CENTRAL WHERE SNOW DEPTHS ARE GREATEST.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 314 AM CST WED NOV 12 2014
MVFR TO LOW VFR CLOUDS BEGINNING TO DISSIPATE ACROSS ALL TAF
SITES. EXPECT THIS TREND TO CONTINUE THROUGH THE EVENING AND INTO
THE EARLY OVERNIGHT HOURS. MVFR CLOUDS OVER EASTERN MONTANA HAVE
MOVED TO KDIK...BUT LATEST RAP/HRRR KEEP THE CLOUDS OUT SO WILL
LIKELY ADD A TEMPO GROUP HERE AS CLOUDS GO IN AND OUT. AFTER 12
UTC THURSDAY WE SHOULD SEE AN IMPROVEMENT TO ALL VFR FROM WEST TO
EAST AS HIGH PRESSURE OVER MONTANA MOVES EAST INTO THE DAKOTAS.
NORTHWEST WINDS WILL CONTINUE TO DIMINISH TONIGHT AND REMAIN
AROUND 5-15 KNOTS FROM THE WEST TO NORTHWEST THURSDAY.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AYD
AVIATION...TWH
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
1233 PM EST THU NOV 13 2014
.SYNOPSIS...
A PROLONGED PERIOD OF BELOW NORMAL TEMPERATURES WILL CONTINUE
THROUGHOUT MUCH OF NEXT WEEK AS A LARGE POOL OF UNSEASONABLY COLD
AIR REMAINS ENTRENCHED OVER THE EASTERN TWO THIRDS OF THE UNITED
STATES. SPRAWLING SURFACE HIGH PRESSURE WILL PROVIDE DRY WEATHER
THROUGH THE END OF THE WORK WEEK AND INTO THE FIRST HALF OF THE WEEKEND.
A COUPLE OF WEATHER SYSTEMS SHIFTING THROUGH THE TENNESSEE AND OHIO
VALLEYS SATURDAY NIGHT THROUGH SUNDAY NIGHT WILL BRING THE THREAT
OF SOME SNOW TO THE AREA...PERHAPS MIXING WITH OR CHANGING TO RAIN
ACROSS KENTUCKY AND SOUTHEAST OHIO ON SUNDAY AFTERNOON AND
EVENING. THE COLDEST AIR OF THE SEASON IS POISED TO MOVE INTO THE
AREA IN THE WAKE OF THESE SYSTEMS EARLY NEXT WEEK...WITH HIGHS
REMAINING BELOW FREEZING...AND LOWS IN THE TEENS AND BRISK WINDS.
&&
.NEAR TERM /THROUGH TONIGHT/...
AN UPR LVL TROF AXIS WILL CONTINUE TO SHIFT EAST/SOUTHEAST INTO
THE GREAT LAKES AND OHIO VALLEY TODAY. WEAK LIFT AND DEEPEST
MOISTURE AHEAD OF THIS TROF IS CURRENTLY OVER THE REGION. THERE
APPEARS TO BE ENOUGH SEPARATION BETWEEN MID LEVEL CLOUD DECK AND
LOWER LEVEL STRATOCUMULUS TO PREVENT A SEED/FEEDER SET UP PER WEAK
ECHO RETURNS ON KILN RADAR. THE EXCEPTION IS PERHAPS THE FAR NW.
RAP/HRRR MODELS SUGGEST THAT THE DEEPEST MOISTURE WILL SHIFT EAST
TODAY. HOWEVER...WITH A WEAK SFC TROF AXIS REFLECTED AT THE
SFC...COMBINED WITH CAA OVER LAKE MICHIGAN...A FEW SNOW SHOWERS
MAY BE POSSIBLE...ESPECIALLY NORTH. HAVE ADDED ISOLATED SNOW
SHOWERS IN THESE LOCATIONS. RADAR AND SATELLITE TRENDS DEPICT
FLURRY DEVELOPMENT TO OUR WEST IN THE LOW LEVEL MOIST CAA.
AS A RESULT...AM NOW EXPECTING SOME SCATTERED FLURRIES ELSEWHERE
AS THIS LOW LEVEL MOISTURE INTERSECTS THE FAVORABLE DENDRITIC
GROWTH ZONE...ALLOWING THE MOIST...UNSTABLE LAYER TO SQUEEZE OUT A
FEW DENDRITES. HIGHS TODAY WILL RANGE FROM THE UPPER 20S WEST TO
THE MID 30S EAST...SOME 20 DEGREES BELOW NORMAL FOR MID NOVEMBER.
FOR TONIGHT...HIGHER RES NAM-WRF AND EVEN TO A DEGREE GFS DATA
SUGGESTS 900-800MB RH WILL REMAIN HIGH OR EVEN INCREASE TONIGHT AS
COLD ADVECTION CONTINUES WITH -14C 850MB POOL ROTATING EAST RIGHT
ACROSS THE CWA TONIGHT. DESPITE SUBSIDENCE THAT CONTINUES TO
INCREASE...WILL ONLY ALLOW FOR A VERY SLOW EROSION OF CLOUDS AND
IT MAY VERY WELL REMAIN MOSTLY CLOUDY THROUGH THE NIGHT AS WELL.
FOR THIS REASON...KEEPING MIN TEMPS ON THE WARM SIDE OF
STATISTICAL MOS. AT SOME POINT MAY NEED TO MENTION A FLURRY OR
LIGHT SNOW SHOWER REMAINING INTACT ALL THE WAY FROM LAKE MICHIGAN
INTO AREAS NORTH OF I-70 /REF VERY WEAK SIMULATE REFLECTIVITY ON
RECENT HR RR RUNS INTO AUGLAIZE/HARDIN COUNTIES/
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY/...
THIS A QUIET...COLD PERIOD. POOL OF -14C /850MB/ AIR ONLY VERY
SLOWLY MODIFIES ON FRIDAY...WITH VERY SIMILAR 925MB TEMPS AS ON
THURSDAY...SO KEEPING HIGH TEMPS VERY SIMILAR TO FRIDAY WITH
EMPHASIS ON RELATIVELY HIGHER TERRAIN AREAS THE COOLEST AND
WARMEST OVER IN THE SCIOTO VALLEY. AM BANKING ON MORE SUNSHINE ON
FRIDAY ESPECIALLY THE FURTHER SOUTH ONE GOES IN THE ILN FORECAST
AREA...GIVEN TRAJECTORIES OF LOW LEVEL FLOW OFF LAKE MICHIGAN
FOCUSING THE BETTER STREAMERS OF LAKE EFFECT CLOUDS INTO AREA
ALONG/NORTH OF I-70. THAT BEING SAID...PESKY SUBSIDENCE INVERSION
REMAINS ON 13.00Z NAM/GFS SOUNDINGS INTO FRIDAY AFTERNOON WITH
STRONG DEEP TROPOSPHERIC SUBSIDENCE SIGNAL ALOFT. PLENTY OF RH ON
FCST SOUNDINGS...BUT NOT AS MUCH AS THURSDAY...SO THINKING AT
LEAST PARTLY CLOUDY SHOULD WORK BY AFTERNOON MOST AREAS. WE ALWAYS
SEEM TO UNDERESTIMATE HOW LONG THE LOW CLOUDS HANG IN THESE FLOW
REGIMES...SO LOWER CONFIDENCE HERE. AS MENTIONED IN PREVIOUS
DISCUSSIONS...A CHANCE WE COULD TIE OR BARELY BREAK A RECORD LOW
MAXIMUM TEMP RECORD ON FRIDAY...ONLY BECAUSE FRIDAY/S VALUES ARE A
NOTICEABLE BUBBLE OF WARMTH IN THE PERIOD OF RECORD IN COMPARISON
WITH DAYS AROUND IT. CMH /34 DEGREES IN 1916/ HAS THE GREATEST
POTENTIAL FOLLOWED BY 32 DEGREES /CVG IN 1916/ AND DAYTON /31
DEGREES IN 1916/.
IF A GOOD CLEARING TREND DOES OCCUR FRIDAY NIGHT...APPROACH AND
PASSAGE OF 1032MB SURFACE HIGH ACROSS SRN OH AND KENTUCKY SHOULD
MEAN LIGHT WINDS OVERNIGHT AND POTENTIAL FOR GOOD TEMP DROP.
CONTINUE TO MENTION MID/UPPER TEENS MOST AREAS WITH A BIAS
CORRECTION INFLUENCE ON THE TEMP GRID TO BRING OUT THE RELATIVE
WARM/COOL SPOTS. WOULD NOT BE AT ALL SURPRISED TO SEE SOME OF THE
REAL NOOKS AND CRANNIES PRONE TO COLD AIR SEEPAGE DROP DOWN IN THE
LOWER TEENS IF SKIES GO CLEAR EARLY IN THE NIGHT.
QUIET WEATHER CONTINUES INTO SATURDAY. SYSTEMS WE WILL NEED TO
START WATCHING FOR LATER IN THE WEEKEND /SEE MORE IN LONG TERM
DISCUSSION BELOW/ WILL BE 1) DIGGING SOUTHWARD THROUGH NRN
ROCKIES...DOWN THE BACKSIDE OF ANOMALOUS WRN CANADA
ANTICYCLONE...AND 2) WEAKER WAVE OVER THE FOUR CORNERS. FLOW OVER
THE OHIO VALLEY WILL BE BACKING AND FLATTENING IN THE BASAL
PORTION OF THE MASSIVE LONG WAVE TROUGH...AND DESPITE SOME RATHER
DECENT MID LEVEL HEIGHT RISES DURING THE DAY ON SATURDAY...LOW
LEVEL TEMPS WILL BE SLOWER TO RESPOND. DUE TO WEAK
TRAJECTORIES/POOR MIXING ON BACKSIDE OF STRONG SURFACE HIGH
PUSHING SOUTHEAST OF AREA. LIKELY TO BE AN INCREASE IN CIRRUS SAT
AFTN AND WHATEVER REMNANT LOW CLOUDS MAY STILL BE HANGING
AROUND...BUT THIS DAY PROBABLY HAS THE POTENTIAL OF A GOOD AMOUNT
OF SUNSHINE...WHICH WILL ALLOW TEMPS BACK INTO THE MID/UPPER 30S.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
WEAK WAVE OVER THE FOUR CORNERS SATURDAY MORNING WILL BE EJECTED
QUICKLY ON FAST LY FLOW THROUGH THE BASE OF L/W TROUGH INTO THE
OHIO VALLEY SAT NIGHT. MOISTURE STARVED...WEAK VERTICAL MOTION
SUGGESTS A CONTINUED LOW/MID RANGE MENTION OF LIGHT SNOW CHANCES
LATER SATURDAY NIGHT. HAVE SLOWED DOWN THE MENTION OF SNOW A
LITTLE FROM PREVIOUS FORECAST. INCREASING/THICKENING CLOUDS SAT
NIGHT SHOULD KEEP LOWS A GOOD DEAL WARMER ON SAT NIGHT IN
COMPARISON TO FRI NIGHT.
WAVE OF INTEREST THOUGH WILL ITSELF BE DIGGING THROUGH THE FOUR
CORNERS BY SUNDAY MORNING SET TO EJECT QUICKLY EAST...THOUGH AT A
LOWER LATITUDE WITH IT BEING STRONGER AND A DEEPER DIG THROUGH THE
L/W TROUGH. THIS WAVE WILL BEGIN TO PHASE WITH AN EVEN STRONGER
SHORTWAVE DIGGING SOUTHEAST THROUGH THE WESTERN GREAT LAKES ON
SUNDAY AFTERNOON...WHICH IN AN OVERALL SENSE GREATLY
AMPLIFIES/SHARPENS THE LONGWAVE TROUGH. WEIGHTED GFS PROGS FOR
SUNDAY/MONDAY HAVE SHOWN A STRONG AMPLIFICATION SIGNAL IN RUN-
0VER-RUN SENSE WITH THIS DEEPENING UPPER TROUGH WITH LOWERING
HEIGHTS IN THE BASE OF THE TROUGH AND INCREASING HEIGHTS W/TIME ON
BOTH UPSTREAM AND DOWNSTREAM RIDGES. IN RESPONSE...PRESSURES WILL
FALL WELL DOWNSTREAM OF THIS PHASING OVER THE GULF COAST INTO THE
APPALACHIANS SUNDAY AFTN/NIGHT WITH MOISTURE ADVECTION IN THE MID
LEVELS TAKING PLACE AND INCREASING DEFORMATION/FGEN FORCING ON THE
WEST SIDE OF THE APPALACHIANS INCLUDING OHIO/IND/KY. THIS SHOULD
PROMOTE A NEWRD TRANSLATING BAND OF PCPN THROUGH KENTUCKY INTO
OHIO/WV SUNDAY AND SUNDAY NIGHT. DPROG/DT TRENDS STILL JUMPY OVER
THE LAST 24 HOURS...BUT SOME CONSENSUS STARTING TO BE SEEN WITH
12.12Z GFS AND 13.00Z GFS LOOKING SIMILAR...WHICH IS A TREND TO
12.00Z AND 12.12Z ECMWF SHOWING PRECIPITATION FOCUSING IN ERN HALF
OF CWA WITH POTENTIAL FOR LIGHT ACCUMULATING SNOWS. DETERMINISTIC
GFS /PARALLEL AND OPNL/ CONTINUE TO BE COLDER THAN ECMWF WITH ALL
SNOW SCENARIO...WHILE RECENT ECMWF RUNS VERY STABLE IN SUGGESTING
PERHAPS A RAIN/SNOW POTENTIAL IN OUR FAR SOUTHERN/EASTERN AREAS.
INCREASED PCPN CHANCES BRINGING LIKELY CHANCES BACK TO CVG/ILN/CMH
AND BLENDED THERMAL PROFILES OF COLDER GFS/WARMER ECMWF TO ARRIVE
AT PTYPE. 12.18Z GEFS PROBS SUPPORT THE LIKELY POPS IN OUR
SOUTH/EAST AT THIS TIME RANGE...AND THERE IS ACKNOWLEDGMENT THAT
IF NEW 12Z DETERMINISTIC ECMWF/GFS CONTINUE TO STABILIZE THAT
HIGHER CHANCES OF PCPN WILL BE NEEDED CWA-WIDE THOUGH THERE IS A
TIGHT GRADIENT IN OUR WEST AS OF NOW. POTENTIAL FOR LIGHT SNOW
ACCUMULATIONS FOR MANY ON SUN/SUN NIGHT. MOST CONSENSUS FOCUS
RIGHT NOW IS EAST OF I-71.
SYSTEM PUSHES EAST MONDAY WITH CORE OF COLDEST AIR IN THIS PATTERN
DROPPING SOUTH AND THEN EAST RIGHT ACROSS THE CWA MON NIGHT AND
TUES. 850MB TEMPS TO -18C SEEMS LIKELY...WHICH PUTS US AT VERY
EDGE OF THE ENVELOPE IN TERMS OF THE CLIMO SPECTRUM SEEN IN BOTH
GEFS AND NAEFS REFORECAST PERCENTILES...MEANING FOR WHAT IS BEING
FORECAST BY THE ENSEMBLE SYSTEMS AT THIS TIME RANGE IS UNUSUAL TO
BE THIS DEEP/COLD WITH THE UPPER TROUGH. M-CLIMATE NUMBERS /GEFS/ AND
REFORECAST PERCENTILES /NAEFS/ ARE EITHER AT THEIR MINS OR VERY NEAR
THE MIN. AUTUMN READING OF -18C AT 850 MB AT ILN/DAY HAS ONLY
HAPPENED ONCE IN THE SOUNDING DATA CLIMATOLOGY ON OR BEFORE
NOVEMBER 19TH HAS ONLY HAPPENED ONE TIME /12Z ON NOVEMBER 13
1986 -- -19.3C/. WITH 500MB HEIGHTS/850MB TEMPS BOTH APPROACHING
BUT JUST FALLING SHY OF 3 SIGMA BELOW CLIMO...WE PROBABLY SHOULD
CONSIDER THE POTENTIAL FOR RECORD TYING/BREAKING TEMPS IN ONE OR
MORE OF THESE PERIODS. FOR RIGHT NOW GIVEN WE/RE STILL 5 DAYS
AWAY...WILL FOCUS ON TUESDAY MAX TEMPS GIVEN THIS IS WHEN CORE OF
COLDEST AIR PASSES OVERHEAD IN BASE OF THERMAL TROUGH. SO PUT TUES MAX
TEMPS RIGHT AT RECORD LOW MAX VALUES FOR RIGHT NOW AND WE CAN
EVALUATE FURTHER DROPS IF NEEDED. LOW CLOUDS IN LEE OF WARM GREAT
LAKES MAY KEEP RECORD MINS UNATTAINABLE AND PLAYING IT THIS WAY
RIGHT NOW AS RECORD LOWS ARE VERY COLD ON NOV 19TH. SOMETHING TO
WATCH...EITHER WAY...VERY CHILLY FOR MID NOV BUT OUTSIDE OF FLURRY
OR PERHAPS A SNOW SHOWER THREAT...MON/TUES SHOULD BE DRY.
STILL LOOKS LIKE THIS STRETCH WILL END UP VERY SIMILAR TO NOVEMBER
STRETCHES IN 1991...1996...AND 1997. ALL THREE OF THOSE YEARS HAD
8-9 DAY STRETCHES WHERE AVERAGE DAILY TEMPS FOR THE PERIOD WERE
NEAR 30F...AND ARE SOME THE CHILLIEST EARLY-MID NOVEMBER LONGER
DURATION PERIODS ON RECORD.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
A MID LEVEL TROUGH WILL PUSH EAST/SOUTHEAST THROUGH THE GREAT
LAKES AND OHIO VALLEY THROUGH TONIGHT. FOR THIS AFTERNOON INTO
EARLY THIS EVENING...MOISTURE BETWEEN 900 MB-850 MB IS A LITTLE
UNSTABLE AND ALSO INTERSECTING THE FAVORABLE SNOW GROWTH ZONE. AS
A RESULT...SOME SCATTERED FLURRIES CAN BE EXPECTED. THESE FLURRIES
SHOULD DIMINISH BY THIS EVENING AS THE ATMOSPHERE STABILIZES SOME
DUE TO SURFACE COOLING. THERE WILL ALSO BE SOME POCKETS OF MVFR
CEILINGS...MAINLY ACROSS THE NORTHERN TAF SITES. FOR LATER
TONIGHT...SCATTERED TO BROKEN STRATOCUMULUS WILL LINGER AS 850 MB
COLD POOL SETTLES INTO THE REGION. CEILINGS SHOULD REMAIN VFR.
ON FRIDAY...MID LEVEL TROUGH MOVE EAST AS SURFACE HIGH PRESSURE
BUILDS INTO THE REGION FROM THE WEST. WILL CONTINUE TO SEE
SCATTERED TO BROKEN STRATOCUMULUS THROUGH THE DAY UNTIL THE 850 MB
COOL POOL/MOISTURE MOVE OFF DURING FRIDAY NIGHT AS SKIES CLEAR.
OUTLOOK...MVFR/IFR CEILINGS AND VISIBILITIES POSSIBLE SATURDAY
NIGHT INTO MONDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...BINAU
NEAR TERM...BINAU/HICKMAN
SHORT TERM...BINAU
LONG TERM...BINAU
AVIATION...HICKMAN
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
1136 AM EST THU NOV 13 2014
.SYNOPSIS...
A PROLONGED PERIOD OF BELOW NORMAL TEMPERATURES WILL CONTINUE
THROUGHOUT MUCH OF NEXT WEEK AS A LARGE POOL OF UNSEASONABLY COLD
AIR REMAINS ENTRENCHED OVER THE EASTERN TWO THIRDS OF THE UNITED
STATES. SPRAWLING SURFACE HIGH PRESSURE WILL PROVIDE DRY WEATHER
THROUGH THE END OF THE WORK WEEK AND INTO THE FIRST HALF OF THE WEEKEND.
A COUPLE OF WEATHER SYSTEMS SHIFTING THROUGH THE TENNESSEE AND OHIO
VALLEYS SATURDAY NIGHT THROUGH SUNDAY NIGHT WILL BRING THE THREAT
OF SOME SNOW TO THE AREA...PERHAPS MIXING WITH OR CHANGING TO RAIN
ACROSS KENTUCKY AND SOUTHEAST OHIO ON SUNDAY AFTERNOON AND
EVENING. THE COLDEST AIR OF THE SEASON IS POISED TO MOVE INTO THE
AREA IN THE WAKE OF THESE SYSTEMS EARLY NEXT WEEK...WITH HIGHS
REMAINING BELOW FREEZING...AND LOWS IN THE TEENS AND BRISK WINDS.
&&
.NEAR TERM /THROUGH TONIGHT/...
AN UPR LVL TROF AXIS WILL CONTINUE TO SHIFT EAST/SOUTHEAST INTO
THE GREAT LAKES AND OHIO VALLEY TODAY. WEAK LIFT AND DEEPEST
MOISTURE AHEAD OF THIS TROF IS CURRENTLY OVER THE REGION. THERE
APPEARS TO BE ENOUGH SEPARATION BETWEEN MID LEVEL CLOUD DECK AND
LOWER LEVEL STRATOCUMULUS TO PREVENT A SEED/FEEDER SET UP PER WEAK
ECHO RETURNS ON KILN RADAR. THE EXCEPTION IS PERHAPS THE FAR NW.
RAP/HRRR MODELS SUGGEST THAT THE DEEPEST MOISTURE WILL SHIFT EAST
TODAY. HOWEVER...WITH A WEAK SFC TROF AXIS REFLECTED AT THE
SFC...COMBINED WITH CAA OVER LAKE MICHIGAN...A FEW SNOW SHOWERS
MAY BE POSSIBLE...ESPECIALLY NORTH. HAVE ADDED ISOLATED SNOW
SHOWERS IN THESE LOCATIONS. RADAR AND SATELLITE TRENDS DEPICT
FLURRY DEVELOPMENT TO OUR WEST IN THE LOW LEVEL MOIST CAA.
AS A RESULT...AM NOW EXPECTING SOME SCATTERED FLURRIES ELSEWHERE
AS THIS LOW LEVEL MOISTURE INTERSECTS THE FAVORABLE DENDRITIC
GROWTH ZONE...ALLOWING THE MOIST...UNSTABLE LAYER TO SQUEEZE OUT A
FEW DENDRITES. HIGHS TODAY WILL RANGE FROM THE UPPER 20S WEST TO
THE MID 30S EAST...SOME 20 DEGREES BELOW NORMAL FOR MID NOVEMBER.
FOR TONIGHT...HIGHER RES NAM-WRF AND EVEN TO A DEGREE GFS DATA
SUGGESTS 900-800MB RH WILL REMAIN HIGH OR EVEN INCREASE TONIGHT AS
COLD ADVECTION CONTINUES WITH -14C 850MB POOL ROTATING EAST RIGHT
ACROSS THE CWA TONIGHT. DESPITE SUBSIDENCE THAT CONTINUES TO
INCREASE...WILL ONLY ALLOW FOR A VERY SLOW EROSION OF CLOUDS AND
IT MAY VERY WELL REMAIN MOSTLY CLOUDY THROUGH THE NIGHT AS WELL.
FOR THIS REASON...KEEPING MIN TEMPS ON THE WARM SIDE OF
STATISTICAL MOS. AT SOME POINT MAY NEED TO MENTION A FLURRY OR
LIGHT SNOW SHOWER REMAINING INTACT ALL THE WAY FROM LAKE MICHIGAN
INTO AREAS NORTH OF I-70 /REF VERY WEAK SIMULATE REFLECTIVITY ON
RECENT HR RR RUNS INTO AUGLAIZE/HARDIN COUNTIES/
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY/...
THIS A QUIET...COLD PERIOD. POOL OF -14C /850MB/ AIR ONLY VERY
SLOWLY MODIFIES ON FRIDAY...WITH VERY SIMILAR 925MB TEMPS AS ON
THURSDAY...SO KEEPING HIGH TEMPS VERY SIMILAR TO FRIDAY WITH
EMPHASIS ON RELATIVELY HIGHER TERRAIN AREAS THE COOLEST AND
WARMEST OVER IN THE SCIOTO VALLEY. AM BANKING ON MORE SUNSHINE ON
FRIDAY ESPECIALLY THE FURTHER SOUTH ONE GOES IN THE ILN FORECAST
AREA...GIVEN TRAJECTORIES OF LOW LEVEL FLOW OFF LAKE MICHIGAN
FOCUSING THE BETTER STREAMERS OF LAKE EFFECT CLOUDS INTO AREA
ALONG/NORTH OF I-70. THAT BEING SAID...PESKY SUBSIDENCE INVERSION
REMAINS ON 13.00Z NAM/GFS SOUNDINGS INTO FRIDAY AFTERNOON WITH
STRONG DEEP TROPOSPHERIC SUBSIDENCE SIGNAL ALOFT. PLENTY OF RH ON
FCST SOUNDINGS...BUT NOT AS MUCH AS THURSDAY...SO THINKING AT
LEAST PARTLY CLOUDY SHOULD WORK BY AFTERNOON MOST AREAS. WE ALWAYS
SEEM TO UNDERESTIMATE HOW LONG THE LOW CLOUDS HANG IN THESE FLOW
REGIMES...SO LOWER CONFIDENCE HERE. AS MENTIONED IN PREVIOUS
DISCUSSIONS...A CHANCE WE COULD TIE OR BARELY BREAK A RECORD LOW
MAXIMUM TEMP RECORD ON FRIDAY...ONLY BECAUSE FRIDAY/S VALUES ARE A
NOTICEABLE BUBBLE OF WARMTH IN THE PERIOD OF RECORD IN COMPARISON
WITH DAYS AROUND IT. CMH /34 DEGREES IN 1916/ HAS THE GREATEST
POTENTIAL FOLLOWED BY 32 DEGREES /CVG IN 1916/ AND DAYTON /31
DEGREES IN 1916/.
IF A GOOD CLEARING TREND DOES OCCUR FRIDAY NIGHT...APPROACH AND
PASSAGE OF 1032MB SURFACE HIGH ACROSS SRN OH AND KENTUCKY SHOULD
MEAN LIGHT WINDS OVERNIGHT AND POTENTIAL FOR GOOD TEMP DROP.
CONTINUE TO MENTION MID/UPPER TEENS MOST AREAS WITH A BIAS
CORRECTION INFLUENCE ON THE TEMP GRID TO BRING OUT THE RELATIVE
WARM/COOL SPOTS. WOULD NOT BE AT ALL SURPRISED TO SEE SOME OF THE
REAL NOOKS AND CRANNIES PRONE TO COLD AIR SEEPAGE DROP DOWN IN THE
LOWER TEENS IF SKIES GO CLEAR EARLY IN THE NIGHT.
QUIET WEATHER CONTINUES INTO SATURDAY. SYSTEMS WE WILL NEED TO
START WATCHING FOR LATER IN THE WEEKEND /SEE MORE IN LONG TERM
DISCUSSION BELOW/ WILL BE 1) DIGGING SOUTHWARD THROUGH NRN
ROCKIES...DOWN THE BACKSIDE OF ANOMALOUS WRN CANADA
ANTICYCLONE...AND 2) WEAKER WAVE OVER THE FOUR CORNERS. FLOW OVER
THE OHIO VALLEY WILL BE BACKING AND FLATTENING IN THE BASAL
PORTION OF THE MASSIVE LONG WAVE TROUGH...AND DESPITE SOME RATHER
DECENT MID LEVEL HEIGHT RISES DURING THE DAY ON SATURDAY...LOW
LEVEL TEMPS WILL BE SLOWER TO RESPOND. DUE TO WEAK
TRAJECTORIES/POOR MIXING ON BACKSIDE OF STRONG SURFACE HIGH
PUSHING SOUTHEAST OF AREA. LIKELY TO BE AN INCREASE IN CIRRUS SAT
AFTN AND WHATEVER REMNANT LOW CLOUDS MAY STILL BE HANGING
AROUND...BUT THIS DAY PROBABLY HAS THE POTENTIAL OF A GOOD AMOUNT
OF SUNSHINE...WHICH WILL ALLOW TEMPS BACK INTO THE MID/UPPER 30S.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
WEAK WAVE OVER THE FOUR CORNERS SATURDAY MORNING WILL BE EJECTED
QUICKLY ON FAST LY FLOW THROUGH THE BASE OF L/W TROUGH INTO THE
OHIO VALLEY SAT NIGHT. MOISTURE STARVED...WEAK VERTICAL MOTION
SUGGESTS A CONTINUED LOW/MID RANGE MENTION OF LIGHT SNOW CHANCES
LATER SATURDAY NIGHT. HAVE SLOWED DOWN THE MENTION OF SNOW A
LITTLE FROM PREVIOUS FORECAST. INCREASING/THICKENING CLOUDS SAT
NIGHT SHOULD KEEP LOWS A GOOD DEAL WARMER ON SAT NIGHT IN
COMPARISON TO FRI NIGHT.
WAVE OF INTEREST THOUGH WILL ITSELF BE DIGGING THROUGH THE FOUR
CORNERS BY SUNDAY MORNING SET TO EJECT QUICKLY EAST...THOUGH AT A
LOWER LATITUDE WITH IT BEING STRONGER AND A DEEPER DIG THROUGH THE
L/W TROUGH. THIS WAVE WILL BEGIN TO PHASE WITH AN EVEN STRONGER
SHORTWAVE DIGGING SOUTHEAST THROUGH THE WESTERN GREAT LAKES ON
SUNDAY AFTERNOON...WHICH IN AN OVERALL SENSE GREATLY
AMPLIFIES/SHARPENS THE LONGWAVE TROUGH. WEIGHTED GFS PROGS FOR
SUNDAY/MONDAY HAVE SHOWN A STRONG AMPLIFICATION SIGNAL IN RUN-
0VER-RUN SENSE WITH THIS DEEPENING UPPER TROUGH WITH LOWERING
HEIGHTS IN THE BASE OF THE TROUGH AND INCREASING HEIGHTS W/TIME ON
BOTH UPSTREAM AND DOWNSTREAM RIDGES. IN RESPONSE...PRESSURES WILL
FALL WELL DOWNSTREAM OF THIS PHASING OVER THE GULF COAST INTO THE
APPALACHIANS SUNDAY AFTN/NIGHT WITH MOISTURE ADVECTION IN THE MID
LEVELS TAKING PLACE AND INCREASING DEFORMATION/FGEN FORCING ON THE
WEST SIDE OF THE APPALACHIANS INCLUDING OHIO/IND/KY. THIS SHOULD
PROMOTE A NEWRD TRANSLATING BAND OF PCPN THROUGH KENTUCKY INTO
OHIO/WV SUNDAY AND SUNDAY NIGHT. DPROG/DT TRENDS STILL JUMPY OVER
THE LAST 24 HOURS...BUT SOME CONSENSUS STARTING TO BE SEEN WITH
12.12Z GFS AND 13.00Z GFS LOOKING SIMILAR...WHICH IS A TREND TO
12.00Z AND 12.12Z ECMWF SHOWING PRECIPITATION FOCUSING IN ERN HALF
OF CWA WITH POTENTIAL FOR LIGHT ACCUMULATING SNOWS. DETERMINISTIC
GFS /PARALLEL AND OPNL/ CONTINUE TO BE COLDER THAN ECMWF WITH ALL
SNOW SCENARIO...WHILE RECENT ECMWF RUNS VERY STABLE IN SUGGESTING
PERHAPS A RAIN/SNOW POTENTIAL IN OUR FAR SOUTHERN/EASTERN AREAS.
INCREASED PCPN CHANCES BRINGING LIKELY CHANCES BACK TO CVG/ILN/CMH
AND BLENDED THERMAL PROFILES OF COLDER GFS/WARMER ECMWF TO ARRIVE
AT PTYPE. 12.18Z GEFS PROBS SUPPORT THE LIKELY POPS IN OUR
SOUTH/EAST AT THIS TIME RANGE...AND THERE IS ACKNOWLEDGMENT THAT
IF NEW 12Z DETERMINISTIC ECMWF/GFS CONTINUE TO STABILIZE THAT
HIGHER CHANCES OF PCPN WILL BE NEEDED CWA-WIDE THOUGH THERE IS A
TIGHT GRADIENT IN OUR WEST AS OF NOW. POTENTIAL FOR LIGHT SNOW
ACCUMULATIONS FOR MANY ON SUN/SUN NIGHT. MOST CONSENSUS FOCUS
RIGHT NOW IS EAST OF I-71.
SYSTEM PUSHES EAST MONDAY WITH CORE OF COLDEST AIR IN THIS PATTERN
DROPPING SOUTH AND THEN EAST RIGHT ACROSS THE CWA MON NIGHT AND
TUES. 850MB TEMPS TO -18C SEEMS LIKELY...WHICH PUTS US AT VERY
EDGE OF THE ENVELOPE IN TERMS OF THE CLIMO SPECTRUM SEEN IN BOTH
GEFS AND NAEFS REFORECAST PERCENTILES...MEANING FOR WHAT IS BEING
FORECAST BY THE ENSEMBLE SYSTEMS AT THIS TIME RANGE IS UNUSUAL TO
BE THIS DEEP/COLD WITH THE UPPER TROUGH. M-CLIMATE NUMBERS /GEFS/ AND
REFORECAST PERCENTILES /NAEFS/ ARE EITHER AT THEIR MINS OR VERY NEAR
THE MIN. AUTUMN READING OF -18C AT 850 MB AT ILN/DAY HAS ONLY
HAPPENED ONCE IN THE SOUNDING DATA CLIMATOLOGY ON OR BEFORE
NOVEMBER 19TH HAS ONLY HAPPENED ONE TIME /12Z ON NOVEMBER 13
1986 -- -19.3C/. WITH 500MB HEIGHTS/850MB TEMPS BOTH APPROACHING
BUT JUST FALLING SHY OF 3 SIGMA BELOW CLIMO...WE PROBABLY SHOULD
CONSIDER THE POTENTIAL FOR RECORD TYING/BREAKING TEMPS IN ONE OR
MORE OF THESE PERIODS. FOR RIGHT NOW GIVEN WE/RE STILL 5 DAYS
AWAY...WILL FOCUS ON TUESDAY MAX TEMPS GIVEN THIS IS WHEN CORE OF
COLDEST AIR PASSES OVERHEAD IN BASE OF THERMAL TROUGH. SO PUT TUES MAX
TEMPS RIGHT AT RECORD LOW MAX VALUES FOR RIGHT NOW AND WE CAN
EVALUATE FURTHER DROPS IF NEEDED. LOW CLOUDS IN LEE OF WARM GREAT
LAKES MAY KEEP RECORD MINS UNATTAINABLE AND PLAYING IT THIS WAY
RIGHT NOW AS RECORD LOWS ARE VERY COLD ON NOV 19TH. SOMETHING TO
WATCH...EITHER WAY...VERY CHILLY FOR MID NOV BUT OUTSIDE OF FLURRY
OR PERHAPS A SNOW SHOWER THREAT...MON/TUES SHOULD BE DRY.
STILL LOOKS LIKE THIS STRETCH WILL END UP VERY SIMILAR TO NOVEMBER
STRETCHES IN 1991...1996...AND 1997. ALL THREE OF THOSE YEARS HAD
8-9 DAY STRETCHES WHERE AVERAGE DAILY TEMPS FOR THE PERIOD WERE
NEAR 30F...AND ARE SOME THE CHILLIEST EARLY-MID NOVEMBER LONGER
DURATION PERIODS ON RECORD.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
MVFR/LOW VFR STRATOCUMULUS DECK IS TRYING TO ERODE AWAY FROM THE
WEST WITH SOME LOW LEVEL CLEARING WORKING ACROSS MUCH OF CENTRAL
INDIANA. LOWER CLOUDS ARE A LITTLE DIFFICULT TO MAKE OUT ON
SATELLITE GIVEN SOME OF THE MID LEVEL CLOUDS ALSO MOVING ACROSS
THE AREA...BUT IT DOES LOOK LIKE THE EASTWARD PROGRESSION OF THE LOWER
CLOUD CLEARING MAY HAVE SLOWED DOWN ON THE LAST COUPLE OF IMAGES.
MODELS ARE SUGGESTING A BIT OF A LOW LEVEL DRY WEDGE POSSIBLY
WORKING ACROSS THE AREA THROUGH LATE MORNING...BUT AM HESITANT TO
BACK AWAY FROM THE MVFR CIGS BASED ON THEIR PERSISTENCE SO FAR.
WILL GO AHEAD AND ALLOW THE CIGS TO LIFT UP INTO VFR THIS
AFTERNOON BUT CONTINUE TO LEAN PESSIMISTIC AND HANG ON TO AT LEAST
A BKN VFR CLOUD DECK THROUGH TONIGHT.
OUTLOOK...MVFR/IFR CEILINGS AND VISIBILITIES POSSIBLE SUNDAY INTO MONDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...BINAU
NEAR TERM...BINAU/HICKMAN
SHORT TERM...BINAU
LONG TERM...BINAU
AVIATION...JGL
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
942 AM EST THU NOV 13 2014
.SYNOPSIS...
A PROLONGED PERIOD OF BELOW NORMAL TEMPERATURES WILL CONTINUE
THROUGHOUT MUCH OF NEXT WEEK AS A LARGE POOL OF UNSEASONABLY COLD
AIR REMAINS ENTRENCHED OVER THE EASTERN TWO THIRDS OF THE UNITED
STATES. SPRAWLING SURFACE HIGH PRESSURE WILL PROVIDE DRY WEATHER
THROUGH THE END OF THE WORK WEEK AND INTO THE FIRST HALF OF THE WEEKEND.
A COUPLE OF WEATHER SYSTEMS SHIFTING THROUGH THE TENNESSEE AND OHIO
VALLEYS SATURDAY NIGHT THROUGH SUNDAY NIGHT WILL BRING THE THREAT
OF SOME SNOW TO THE AREA...PERHAPS MIXING WITH OR CHANGING TO RAIN
ACROSS KENTUCKY AND SOUTHEAST OHIO ON SUNDAY AFTERNOON AND
EVENING. THE COLDEST AIR OF THE SEASON IS POISED TO MOVE INTO THE
AREA IN THE WAKE OF THESE SYSTEMS EARLY NEXT WEEK...WITH HIGHS
REMAINING BELOW FREEZING...AND LOWS IN THE TEENS AND BRISK WINDS.
&&
.NEAR TERM /THROUGH TONIGHT/...
AN UPR LVL TROF AXIS WILL CONTINUE TO SHIFT EAST/SOUTHEAST INTO
THE GREAT LAKES AND OHIO VALLEY TODAY. WEAK LIFT AND DEEPEST
MOISTURE AHEAD OF THIS TROF IS CURRENTLY OVER THE REGION. THERE
APPEARS TO BE ENOUGH SEPARATION BETWEEN MID LEVEL CLOUD DECK AND
LOWER LEVEL STRATOCUMULUS TO PREVENT A SEED/FEEDER SET UP PER WEAK
ECHO RETURNS ON KILN RADAR. THE EXCEPTION IS PERHAPS THE FAR NW.
RAP/HRRR MODELS SUGGEST THAT THE DEEPEST MOISTURE WILL SHIFT EAST
TODAY. HOWEVER...WITH A WEAK SFC TROF AXIS REFLECTED AT THE
SFC...COMBINED WITH CAA OVER LAKE MICHIGAN...A FEW SNOW SHOWERS
MAY BE POSSIBLE...ESPECIALLY NORTH. HAVE ADDED SLIGHT CHANCES OF
SNOW SHOWERS IN THESE LOCATIONS. WILL MONITOR RADAR TRENDS TO SEE
IF THIS NEEDS TO BE PULLED FARTHER SOUTH. IN ADDITION...THERE MAY
BE THE POSSIBILITY OF A FEW FLURRIES ELSEWHERE AS LOW LEVEL
MOISTURE INTERSECTS THE FAVORABLE DENDRITIC GROWTH ZONE IN WHICH
THE SHALLOW UNSTABLE MOIST LAYER MAY SQUEEZE OUT A FEW FLURRIES.
HIGHS TODAY WILL RANGE FROM THE LOWER 30S EAST TO THE MID 30S
WEST...SOME 20 DEGREES BELOW NORMAL FOR MID NOVEMBER.
FOR TONIGHT...HIGHER RES NAM-WRF AND EVEN TO A DEGREE GFS DATA
SUGGESTS 900-800MB RH WILL REMAIN HIGH OR EVEN INCREASE TONIGHT AS
COLD ADVECTION CONTINUES WITH -14C 850MB POOL ROTATING EAST RIGHT
ACROSS THE CWA TONIGHT. DESPITE SUBSIDENCE THAT CONTINUES TO
INCREASE...WILL ONLY ALLOW FOR A VERY SLOW EROSION OF CLOUDS AND
IT MAY VERY WELL REMAIN MOSTLY CLOUDY THROUGH THE NIGHT AS WELL.
FOR THIS REASON...KEEPING MIN TEMPS ON THE WARM SIDE OF
STATISTICAL MOS. AT SOME POINT MAY NEED TO MENTION A FLURRY OR
LIGHT SNOW SHOWER REMAINING INTACT ALL THE WAY FROM LAKE MICHIGAN
INTO AREAS NORTH OF I-70 /REF VERY WEAK SIMULATE REFLECTIVITY ON
RECENT HRRR RUNS INTO AUGLAIZE/HARDIN COUNTIES/
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY/...
THIS A QUIET...COLD PERIOD. POOL OF -14C /850MB/ AIR ONLY VERY
SLOWLY MODIFIES ON FRIDAY...WITH VERY SIMILAR 925MB TEMPS AS ON
THURSDAY...SO KEEPING HIGH TEMPS VERY SIMILAR TO FRIDAY WITH
EMPHASIS ON RELATIVELY HIGHER TERRAIN AREAS THE COOLEST AND
WARMEST OVER IN THE SCIOTO VALLEY. AM BANKING ON MORE SUNSHINE ON
FRIDAY ESPECIALLY THE FURTHER SOUTH ONE GOES IN THE ILN FORECAST
AREA...GIVEN TRAJECTORIES OF LOW LEVEL FLOW OFF LAKE MICHIGAN
FOCUSING THE BETTER STREAMERS OF LAKE EFFECT CLOUDS INTO AREA
ALONG/NORTH OF I-70. THAT BEING SAID...PESKY SUBSIDENCE INVERSION
REMAINS ON 13.00Z NAM/GFS SOUNDINGS INTO FRIDAY AFTERNOON WITH
STRONG DEEP TROPOSPHERIC SUBSIDENCE SIGNAL ALOFT. PLENTY OF RH ON
FCST SOUNDINGS...BUT NOT AS MUCH AS THURSDAY...SO THINKING AT
LEAST PARTLY CLOUDY SHOULD WORK BY AFTERNOON MOST AREAS. WE ALWAYS
SEEM TO UNDERESTIMATE HOW LONG THE LOW CLOUDS HANG IN THESE FLOW
REGIMES...SO LOWER CONFIDENCE HERE. AS MENTIONED IN PREVIOUS
DISCUSSIONS...A CHANCE WE COULD TIE OR BARELY BREAK A RECORD LOW
MAXIMUM TEMP RECORD ON FRIDAY...ONLY BECAUSE FRIDAY/S VALUES ARE A
NOTICEABLE BUBBLE OF WARMTH IN THE PERIOD OF RECORD IN COMPARISON
WITH DAYS AROUND IT. CMH /34 DEGREES IN 1916/ HAS THE GREATEST
POTENTIAL FOLLOWED BY 32 DEGREES /CVG IN 1916/ AND DAYTON /31
DEGREES IN 1916/.
IF A GOOD CLEARING TREND DOES OCCUR FRIDAY NIGHT...APPROACH AND
PASSAGE OF 1032MB SURFACE HIGH ACROSS SRN OH AND KENTUCKY SHOULD
MEAN LIGHT WINDS OVERNIGHT AND POTENTIAL FOR GOOD TEMP DROP.
CONTINUE TO MENTION MID/UPPER TEENS MOST AREAS WITH A BIAS
CORRECTION INFLUENCE ON THE TEMP GRID TO BRING OUT THE RELATIVE
WARM/COOL SPOTS. WOULD NOT BE AT ALL SURPRISED TO SEE SOME OF THE
REAL NOOKS AND CRANNIES PRONE TO COLD AIR SEEPAGE DROP DOWN IN THE
LOWER TEENS IF SKIES GO CLEAR EARLY IN THE NIGHT.
QUIET WEATHER CONTINUES INTO SATURDAY. SYSTEMS WE WILL NEED TO
START WATCHING FOR LATER IN THE WEEKEND /SEE MORE IN LONG TERM
DISCUSSION BELOW/ WILL BE 1) DIGGING SOUTHWARD THROUGH NRN
ROCKIES...DOWN THE BACKSIDE OF ANOMALOUS WRN CANADA
ANTICYCLONE...AND 2) WEAKER WAVE OVER THE FOUR CORNERS. FLOW OVER
THE OHIO VALLEY WILL BE BACKING AND FLATTENING IN THE BASAL
PORTION OF THE MASSIVE LONGWAVE TROUGH...AND DESPITE SOME RATHER
DECENT MID LEVEL HEIGHT RISES DURING THE DAY ON SATURDAY...LOW
LEVEL TEMPS WILL BE SLOWER TO RESPOND. DUE TO WEAK
TRAJECTORIES/POOR MIXING ON BACKSIDE OF STRONG SURFACE HIGH
PUSHING SOUTHEAST OF AREA. LIKELY TO BE AN INCREASE IN CIRRUS SAT
AFTN AND WHATEVER REMNANT LOW CLOUDS MAY STILL BE HANGING
AROUND...BUT THIS DAY PROBABLY HAS THE POTENTIAL OF A GOOD AMOUNT
OF SUNSHINE...WHICH WILL ALLOW TEMPS BACK INTO THE MID/UPPER 30S.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
WEAK WAVE OVER THE FOUR CORNERS SATURDAY MORNING WILL BE EJECTED
QUICKLY ON FAST WLY FLOW THROUGH THE BASE OF L/W TROUGH INTO THE
OHIO VALLEY SAT NIGHT. MOISTURE STARVED...WEAK VERTICAL MOTION
SUGGESTS A CONTINUED LOW/MID RANGE MENTION OF LIGHT SNOW CHANCES
LATER SATURDAY NIGHT. HAVE SLOWED DOWN THE MENTION OF SNOW A
LITTLE FROM PREVIOUS FORECAST. INCREASING/THICKENING CLOUDS SAT
NIGHT SHOULD KEEP LOWS A GOOD DEAL WARMER ON SAT NIGHT IN
COMPARISON TO FRI NIGHT.
WAVE OF INTEREST THOUGH WILL ITSELF BE DIGGING THROUGH THE FOUR
CORNERS BY SUNDAY MORNING SET TO EJECT QUICKLY EAST...THOUGH AT A
LOWER LATITUDE WITH IT BEING STRONGER AND A DEEPER DIG THROUGH THE
L/W TROUGH. THIS WAVE WILL BEGIN TO PHASE WITH AN EVEN STRONGER
SHORTWAVE DIGGING SOUTHEAST THROUGH THE WESTERN GREAT LAKES ON
SUNDAY AFTERNOON...WHICH IN AN OVERALL SENSE GREATLY
AMPLIFIES/SHARPENS THE LONGWAVE TROUGH. WEIGHTED GFS PROGS FOR
SUNDAY/MONDAY HAVE SHOWN A STRONG AMPLIFICATION SIGNAL IN RUN-
0VER-RUN SENSE WITH THIS DEEPENING UPPER TROUGH WITH LOWERING
HEIGHTS IN THE BASE OF THE TROUGH AND INCREASING HEIGHTS W/TIME ON
BOTH UPSTREAM AND DOWNSTREAM RIDGES. IN RESPONSE...PRESSURES WILL
FALL WELL DOWNSTREAM OF THIS PHASING OVER THE GULF COAST INTO THE
APPALACHIANS SUNDAY AFTN/NIGHT WITH MOISTURE ADVECTION IN THE MID
LEVELS TAKING PLACE AND INCREASING DEFORMATION/FGEN FORCING ON THE
WEST SIDE OF THE APPALACHIANS INCLUDING OHIO/IND/KY. THIS SHOULD
PROMOTE A NEWRD TRANSLATING BAND OF PCPN THROUGH KENTUCKY INTO
OHIO/WV SUNDAY AND SUNDAY NIGHT. DPROG/DT TRENDS STILL JUMPY OVER
THE LAST 24 HOURS...BUT SOME CONSENSUS STARTING TO BE SEEN WITH
12.12Z GFS AND 13.00Z GFS LOOKING SIMILAR...WHICH IS A TREND TO
12.00Z AND 12.12Z ECMWF SHOWING PRECIPITATION FOCUSING IN ERN HALF
OF CWA WITH POTENTIAL FOR LIGHT ACCUMULATING SNOWS. DETERMINISTIC
GFS /PARALLEL AND OPNL/ CONTINUE TO BE COLDER THAN ECMWF WITH ALL
SNOW SCENARIO...WHILE RECENT ECMWF RUNS VERY STABLE IN SUGGESTING
PERHAPS A RAIN/SNOW POTENTIAL IN OUR FAR SOUTHERN/EASTERN AREAS.
INCREASED PCPN CHANCES BRINGING LIKELY CHANCES BACK TO CVG/ILN/CMH
AND BLENDED THERMAL PROFILES OF COLDER GFS/WARMER ECMWF TO ARRIVE
AT PTYPE. 12.18Z GEFS PROBS SUPPORT THE LIKELY POPS IN OUR
SOUTH/EAST AT THIS TIME RANGE...AND THERE IS ACKNOWLEDGMENT THAT
IF NEW 12Z DETERMINISTIC ECMWF/GFS CONTINUE TO STABILIZE THAT
HIGHER CHANCES OF PCPN WILL BE NEEDED CWA-WIDE THOUGH THERE IS A
TIGHT GRADIENT IN OUR WEST AS OF NOW. POTENTIAL FOR LIGHT SNOW
ACCUMULATIONS FOR MANY ON SUN/SUN NIGHT. MOST CONSENSUS FOCUS
RIGHT NOW IS EAST OF I-71.
SYSTEM PUSHES EAST MONDAY WITH CORE OF COLDEST AIR IN THIS PATTERN
DROPPING SOUTH AND THEN EAST RIGHT ACROSS THE CWA MON NIGHT AND
TUES. 850MB TEMPS TO -18C SEEMS LIKELY...WHICH PUTS US AT VERY
EDGE OF THE ENVELOPE IN TERMS OF THE CLIMO SPECTRUM SEEN IN BOTH
GEFS AND NAEFS REFORECAST PERCENTILES...MEANING FOR WHAT IS BEING
FORECAST BY THE ENSEMBLE SYSTEMS AT THIS TIME RANGE IS UNUSUAL TO
BE THIS DEEP/COLD WITH THE UPPER TROUGH. M-CLIMATE NUMBERS /GEFS/ AND
REFORECAST PERCENTILES /NAEFS/ ARE EITHER AT THEIR MINS OR VERY NEAR
THE MIN. AUTUMN READING OF -18C AT 850 MB AT ILN/DAY HAS ONLY
HAPPENED ONCE IN THE SOUNDING DATA CLIMATOLOGY ON OR BEFORE
NOVEMBER 19TH HAS ONLY HAPPENED ONE TIME /12Z ON NOVEMBER 13
1986 -- -19.3C/. WITH 500MB HEIGHTS/850MB TEMPS BOTH APPROACHING
BUT JUST FALLING SHY OF 3 SIGMA BELOW CLIMO...WE PROBABLY SHOULD
CONSIDER THE POTENTIAL FOR RECORD TYING/BREAKING TEMPS IN ONE OR
MORE OF THESE PERIODS. FOR RIGHT NOW GIVEN WE/RE STILL 5 DAYS
AWAY...WILL FOCUS ON TUESDAY MAX TEMPS GIVEN THIS IS WHEN CORE OF
COLDEST AIR PASSES OVERHEAD IN BASE OF THERMAL TROUGH. SO PUT TUES MAX
TEMPS RIGHT AT RECORD LOW MAX VALUES FOR RIGHT NOW AND WE CAN
EVALUATE FURTHER DROPS IF NEEDED. LOW CLOUDS IN LEE OF WARM GREAT
LAKES MAY KEEP RECORD MINS UNATTAINABLE AND PLAYING IT THIS WAY
RIGHT NOW AS RECORD LOWS ARE VERY COLD ON NOV 19TH. SOMETHING TO
WATCH...EITHER WAY...VERY CHILLY FOR MID NOV BUT OUTSIDE OF FLURRY
OR PERHAPS A SNOW SHOWER THREAT...MON/TUES SHOULD BE DRY.
STILL LOOKS LIKE THIS STRETCH WILL END UP VERY SIMILAR TO NOVEMBER
STRETCHES IN 1991...1996...AND 1997. ALL THREE OF THOSE YEARS HAD
8-9 DAY STRETCHES WHERE AVERAGE DAILY TEMPS FOR THE PERIOD WERE
NEAR 30F...AND ARE SOME THE CHILLIEST EARLY-MID NOVEMBER LONGER
DURATION PERIODS ON RECORD.
&&
.AVIATION /15Z THURSDAY THROUGH MONDAY/...
MVFR/LOW VFR STRATOCUMULUS DECK IS TRYING TO ERODE AWAY FROM THE
WEST WITH SOME LOW LEVEL CLEARING WORKING ACROSS MUCH OF CENTRAL
INDIANA. LOWER CLOUDS ARE A LITTLE DIFFICULT TO MAKE OUT ON
SATELLITE GIVEN SOME OF THE MID LEVEL CLOUDS ALSO MOVING ACROSS
THE AREA...BUT IT DOES LOOK LIKE THE EASTWARD PROGRESSION OF THE LOWER
CLOUD CLEARING MAY HAVE SLOWED DOWN ON THE LAST COUPLE OF IMAGES.
MODELS ARE SUGGESTING A BIT OF A LOW LEVEL DRY WEDGE POSSIBLY
WORKING ACROSS THE AREA THROUGH LATE MORNING...BUT AM HESITANT TO
BACK AWAY FROM THE MVFR CIGS BASED ON THEIR PERSISTENCE SO FAR.
WILL GO AHEAD AND ALLOW THE CIGS TO LIFT UP INTO VFR THIS
AFTERNOON BUT CONTINUE TO LEAN PESSIMISTIC AND HANG ON TO AT LEAST
A BKN VFR CLOUD DECK THROUGH TONIGHT.
OUTLOOK...MVFR/IFR CEILINGS AND VISIBILITIES POSSIBLE SUNDAY INTO MONDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...BINAU
NEAR TERM...BINAU/HICKMAN
SHORT TERM...BINAU
LONG TERM...BINAU
AVIATION...JGL
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
639 AM EST THU NOV 13 2014
.SYNOPSIS...
A PROLONGED PERIOD OF BELOW NORMAL TEMPERATURES WILL CONTINUE
THROUGHOUT MUCH OF NEXT WEEK AS A LARGE POOL OF UNSEASONABLY COLD
AIR REMAINS ENTRENCHED OVER THE EASTERN TWO THIRDS OF THE UNITED
STATES. SPRAWLING SURFACE HIGH PRESSURE WILL PROVIDE DRY WEATHER
THROUGH THE END OF THE WORK WEEK AND INTO THE FIRST HALF OF THE WEEKEND.
A COUPLE OF WEATHER SYSTEMS SHIFTING THROUGH THE TENNESSEE AND OHIO
VALLEYS SATURDAY NIGHT THROUGH SUNDAY NIGHT WILL BRING THE THREAT
OF SOME SNOW TO THE AREA...PERHAPS MIXING WITH OR CHANGING TO RAIN
ACROSS KENTUCKY AND SOUTHEAST OHIO ON SUNDAY AFTERNOON AND
EVENING. THE COLDEST AIR OF THE SEASON IS POISED TO MOVE INTO THE
AREA IN THE WAKE OF THESE SYSTEMS EARLY NEXT WEEK...WITH HIGHS
REMAINING BELOW FREEZING...AND LOWS IN THE TEENS AND BRISK WINDS.
&&
.NEAR TERM /THROUGH TONIGHT/...
RADAR MOSAICS THIS MORNING HAVE BEEN TRACKING A VERY NARROW BAND
OF LIGHT SNOW ACROSS CNTL/NRN IND STREAKING INTO NWRN OH. THIS
LINES UP VERY WELL WITH RAP/NAM 600MB FRONTOGENETIC FORCING ON THE
ANTICYCLONIC SHEAR SIDE OF NARROW/INTENSE 130KT JET RUNNING FROM
NRN IL INTO MI AND EVENTUALLY ONTARIO. THIS SEEN ON 1.5 PV SURFACE
/DYNAMIC TROPOPAUSE/. MAIN SHORTWAVE TROUGH/PV LOWERING IN THIS
FLOW IS APPROACHING CHICAGO AND IS TRANSLATING QUICKLY DOWNSTREAM
/NORTHEAST/ AND WILL BE NEAR DETROIT BY MIDDAY. MEANWHILE...LOW
LEVEL COLD ADVECTION CONTINUES AS LARGE ERN NOAM TROUGH CONTINUES
TO DEVELOP SWRD AND UPSTREAM 13.00Z RAOBS CONFIRM A HEALTHY/DEEP
SOURCE OF COLD AIR IN PLACE AND SHIFTING SLOWLY SOUTHEAST WITH
KILN /-9C AT 850MB/ GIVING WAY TO -11C TO -14C READINGS AT
KILX/KDTX/KGRB/KMPX. SAID RADAR MOSAICS ALSO SHOWING SLOWLY
GROWING LAKE-EFFECT SNOW SHOWERS/FLURRIES IN LEE OF WARM LAKE
MICHIGAN WATERS. 13.00Z KILN SOUNDING CONTINUED TO SHOW THIN /30
MB DEEP/ LAYER OF SATURATION WITH RESPECT TO ICE BETWEEN 850MB AND
880MB /ABOUT -10C/. GOES FOG PRODUCT CONFIRMS A LARGE AMOUNT OF
STRATUS ACROSS THE AREA BACK INTO MUCH OF INDIANA WHERE MID LVL
FGEN AND APPROACHING PV ANOMALY ARE PRODUCING THICKER/WIDESPREAD
CLOUD ATOP THE LARGE STRATUS SHIELD. SEEMS TO BE JUST ENOUGH
SEPARATION /5KFT/ BETWEEN MID LEVEL MOISTURE AND LOWER LEVEL
MOISTURE TO PREVENT MUCH IN THE WAY OF SEEDER FEEDER FROM THE MID
DECK TO THE LOWER CLOUD AS IT CROSSES THE CWA THIS MORNING.
SO...CONSIDERED RUNNING A FLURRY MENTION ESP THIS MORNING ACROSS
WCNTL/CNTL OHIO AS WEAKENING BAND OF FGEN FORCING SLIDES
EAST/NORTHEAST ACROSS NORTHERN HALF OF OHIO. STILL MAY DO AT SOME
POINT IN THE NEXT FEW HOURS OF RADAR EVAL BUT FOR RIGHT NOW NOT
SEEING ENOUGH TO MENTION. AM REMAINING PESSIMISTIC ON CLOUDS
TODAY...GOING MOSTLY CLOUDY MOST AREAS. WITH MOISTURE SO
THIN...AND OVERALL PROFILE BECOMING QUITE SUBSIDENT IN THE WAKE OF
THE WAVE/FORCING THIS MORNING...SOME HOLES COULD BE CHEWED IN THE
STRATUS ESP THIS AFTN BUT CONSIDERING ITS NOVEMBER...SUBSIDENCE
INVERSION NOT GOING AWAY...AND CAA/LAKE MICHIGAN FEED OF RH IS
PRESENT ON MOST NWP SOLUTIONS...WILL JUST RIDE THE CLOUDS UNTIL WE
SEE MORE SUBSTANTIAL EROSION. 1000-850MB THICKNESS DERIVED
EQUATIONS FROM ILN SOUNDING DATA SUGGEST HIGH TEMPS SHOULD BE A
FEW DEGREES COLDER THAN PVS FORECAST...SO STARTED WITH THIS BUT
NUDGED BACK TO BLENDED MOS WHICH GAVE HIGHS IN THE LOWER/MID 30S
MOST AREAS. IF CLOUDS REMAIN THICK ALL DAY...LOWER SIDE OF THIS
ENVELOPE IS EXPECTED. LATEST HIGHER RES NAM-WRF AND EVEN TO A
DEGREE GFS DATA SUGGESTING 900-800MB RH WILL REMAIN HIGH OR EVEN
INCREASE TONIGHT AS COLD ADVECTION CONTINUES WITH -14C 850MB POOL
ROTATING EAST RIGHT ACROSS THE CWA TONIGHT. DESPITE SUBSIDENCE
THAT CONTINUES TO INCREASE...WILL ONLY ALLOW FOR A VERY SLOW
EROSION OF CLOUDS AND IT MAY VERY WELL REMAIN MOSTLY CLOUDY
THROUGH THE NIGHT AS WELL. FOR THIS REASON...KEEPING MIN TEMPS ON
THE WARM SIDE OF STATISTICAL MOS. AT SOME POINT MAY NEED TO
MENTION A FLURRY OR LIGHT SNOW SHOWER REMAINING INTACT ALL THE WAY
FROM LAKE MICHIGAN INTO AREAS NORTH OF I-70 /REF VERY WEAK
SIMULATE REFLECTIVITY ON RECENT HRRR RUNS INTO AUGLAIZE/HARDIN
COUNTIES/
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY/...
THIS A QUIET...COLD PERIOD. POOL OF -14C /850MB/ AIR ONLY VERY
SLOWLY MODIFIES ON FRIDAY...WITH VERY SIMILAR 925MB TEMPS AS ON
THURSDAY...SO KEEPING HIGH TEMPS VERY SIMILAR TO FRIDAY WITH
EMPHASIS ON RELATIVELY HIGHER TERRAIN AREAS THE COOLEST AND
WARMEST OVER IN THE SCIOTO VALLEY. AM BANKING ON MORE SUNSHINE ON
FRIDAY ESPECIALLY THE FURTHER SOUTH ONE GOES IN THE ILN FORECAST
AREA...GIVEN TRAJECTORIES OF LOW LEVEL FLOW OFF LAKE MICHIGAN
FOCUSING THE BETTER STREAMERS OF LAKE EFFECT CLOUDS INTO AREA
ALONG/NORTH OF I-70. THAT BEING SAID...PESKY SUBSIDENCE INVERSION
REMAINS ON 13.00Z NAM/GFS SOUNDINGS INTO FRIDAY AFTERNOON WITH
STRONG DEEP TROPOSPHERIC SUBSIDENCE SIGNAL ALOFT. PLENTY OF RH ON
FCST SOUNDINGS...BUT NOT AS MUCH AS THURSDAY...SO THINKING AT
LEAST PARTLY CLOUDY SHOULD WORK BY AFTERNOON MOST AREAS. WE ALWAYS
SEEM TO UNDERESTIMATE HOW LONG THE LOW CLOUDS HANG IN THESE FLOW
REGIMES...SO LOWER CONFIDENCE HERE. AS MENTIONED IN PREVIOUS
DISCUSSIONS...A CHANCE WE COULD TIE OR BARELY BREAK A RECORD LOW
MAXIMUM TEMP RECORD ON FRIDAY...ONLY BECAUSE FRIDAY/S VALUES ARE A
NOTICEABLE BUBBLE OF WARMTH IN THE PERIOD OF RECORD IN COMPARISON
WITH DAYS AROUND IT. CMH /34 DEGREES IN 1916/ HAS THE GREATEST
POTENTIAL FOLLOWED BY 32 DEGREES /CVG IN 1916/ AND DAYTON /31
DEGREES IN 1916/.
IF A GOOD CLEARING TREND DOES OCCUR FRIDAY NIGHT...APPROACH AND
PASSAGE OF 1032MB SURFACE HIGH ACROSS SRN OH AND KENTUCKY SHOULD
MEAN LIGHT WINDS OVERNIGHT AND POTENTIAL FOR GOOD TEMP DROP.
CONTINUE TO MENTION MID/UPPER TEENS MOST AREAS WITH A BIAS
CORRECTION INFLUENCE ON THE TEMP GRID TO BRING OUT THE RELATIVE
WARM/COOL SPOTS. WOULD NOT BE AT ALL SURPRISED TO SEE SOME OF THE
REAL NOOKS AND CRANNIES PRONE TO COLD AIR SEEPAGE DROP DOWN IN THE
LOWER TEENS IF SKIES GO CLEAR EARLY IN THE NIGHT.
QUIET WEATHER CONTINUES INTO SATURDAY. SYSTEMS WE WILL NEED TO
START WATCHING FOR LATER IN THE WEEKEND /SEE MORE IN LONG TERM
DISCUSSION BELOW/ WILL BE 1) DIGGING SOUTHWARD THROUGH NRN
ROCKIES...DOWN THE BACKSIDE OF ANOMALOUS WRN CANADA
ANTICYCLONE...AND 2) WEAKER WAVE OVER THE FOUR CORNERS. FLOW OVER
THE OHIO VALLEY WILL BE BACKING AND FLATTENING IN THE BASAL
PORTION OF THE MASSIVE LONGWAVE TROUGH...AND DESPITE SOME RATHER
DECENT MID LEVEL HEIGHT RISES DURING THE DAY ON SATURDAY...LOW
LEVEL TEMPS WILL BE SLOWER TO RESPOND. DUE TO WEAK
TRAJECTORIES/POOR MIXING ON BACKSIDE OF STRONG SURFACE HIGH
PUSHING SOUTHEAST OF AREA. LIKELY TO BE AN INCREASE IN CIRRUS SAT
AFTN AND WHATEVER REMNANT LOW CLOUDS MAY STILL BE HANGING
AROUND...BUT THIS DAY PROBABLY HAS THE POTENTIAL OF A GOOD AMOUNT
OF SUNSHINE...WHICH WILL ALLOW TEMPS BACK INTO THE MID/UPPER 30S.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
WEAK WAVE OVER THE FOUR CORNERS SATURDAY MORNING WILL BE EJECTED
QUICKLY ON FAST WLY FLOW THROUGH THE BASE OF L/W TROUGH INTO THE
OHIO VALLEY SAT NIGHT. MOISTURE STARVED...WEAK VERTICAL MOTION
SUGGESTS A CONTINUED LOW/MID RANGE MENTION OF LIGHT SNOW CHANCES
LATER SATURDAY NIGHT. HAVE SLOWED DOWN THE MENTION OF SNOW A
LITTLE FROM PREVIOUS FORECAST. INCREASING/THICKENING CLOUDS SAT
NIGHT SHOULD KEEP LOWS A GOOD DEAL WARMER ON SAT NIGHT IN
COMPARISON TO FRI NIGHT.
WAVE OF INTEREST THOUGH WILL ITSELF BE DIGGING THROUGH THE FOUR
CORNERS BY SUNDAY MORNING SET TO EJECT QUICKLY EAST...THOUGH AT A
LOWER LATITUDE WITH IT BEING STRONGER AND A DEEPER DIG THROUGH THE
L/W TROUGH. THIS WAVE WILL BEGIN TO PHASE WITH AN EVEN STRONGER
SHORTWAVE DIGGING SOUTHEAST THROUGH THE WESTERN GREAT LAKES ON
SUNDAY AFTERNOON...WHICH IN AN OVERALL SENSE GREATLY
AMPLIFIES/SHARPENS THE LONGWAVE TROUGH. WEIGHTED GFS PROGS FOR
SUNDAY/MONDAY HAVE SHOWN A STRONG AMPLIFICATION SIGNAL IN RUN-
0VER-RUN SENSE WITH THIS DEEPENING UPPER TROUGH WITH LOWERING
HEIGHTS IN THE BASE OF THE TROUGH AND INCREASING HEIGHTS W/TIME ON
BOTH UPSTREAM AND DOWNSTREAM RIDGES. IN RESPONSE...PRESSURES WILL
FALL WELL DOWNSTREAM OF THIS PHASING OVER THE GULF COAST INTO THE
APPALACHIANS SUNDAY AFTN/NIGHT WITH MOISTURE ADVECTION IN THE MID
LEVELS TAKING PLACE AND INCREASING DEFORMATION/FGEN FORCING ON THE
WEST SIDE OF THE APPALACHIANS INCLUDING OHIO/IND/KY. THIS SHOULD
PROMOTE A NEWRD TRANSLATING BAND OF PCPN THROUGH KENTUCKY INTO
OHIO/WV SUNDAY AND SUNDAY NIGHT. DPROG/DT TRENDS STILL JUMPY OVER
THE LAST 24 HOURS...BUT SOME CONSENSUS STARTING TO BE SEEN WITH
12.12Z GFS AND 13.00Z GFS LOOKING SIMILAR...WHICH IS A TREND TO
12.00Z AND 12.12Z ECMWF SHOWING PRECIPITATION FOCUSING IN ERN HALF
OF CWA WITH POTENTIAL FOR LIGHT ACCUMULATING SNOWS. DETERMINISTIC
GFS /PARALLEL AND OPNL/ CONTINUE TO BE COLDER THAN ECMWF WITH ALL
SNOW SCENARIO...WHILE RECENT ECMWF RUNS VERY STABLE IN SUGGESTING
PERHAPS A RAIN/SNOW POTENTIAL IN OUR FAR SOUTHERN/EASTERN AREAS.
INCREASED PCPN CHANCES BRINGING LIKELY CHANCES BACK TO CVG/ILN/CMH
AND BLENDED THERMAL PROFILES OF COLDER GFS/WARMER ECMWF TO ARRIVE
AT PTYPE. 12.18Z GEFS PROBS SUPPORT THE LIKELY POPS IN OUR
SOUTH/EAST AT THIS TIME RANGE...AND THERE IS ACKNOWLEDGMENT THAT
IF NEW 12Z DETERMINISTIC ECMWF/GFS CONTINUE TO STABILIZE THAT
HIGHER CHANCES OF PCPN WILL BE NEEDED CWA-WIDE THOUGH THERE IS A
TIGHT GRADIENT IN OUR WEST AS OF NOW. POTENTIAL FOR LIGHT SNOW
ACCUMULATIONS FOR MANY ON SUN/SUN NIGHT. MOST CONSENSUS FOCUS
RIGHT NOW IS EAST OF I-71.
SYSTEM PUSHES EAST MONDAY WITH CORE OF COLDEST AIR IN THIS PATTERN
DROPPING SOUTH AND THEN EAST RIGHT ACROSS THE CWA MON NIGHT AND
TUES. 850MB TEMPS TO -18C SEEMS LIKELY...WHICH PUTS US AT VERY
EDGE OF THE ENVELOPE IN TERMS OF THE CLIMO SPECTRUM SEEN IN BOTH
GEFS AND NAEFS REFORECAST PERCENTILES...MEANING FOR WHAT IS BEING
FORECAST BY THE ENSEMBLE SYSTEMS AT THIS TIME RANGE IS UNUSUAL TO
BE THIS DEEP/COLD WITH THE UPPER TROUGH. M-CLIMATE NUMBERS /GEFS/ AND
REFORECAST PERCENTILES /NAEFS/ ARE EITHER AT THEIR MINS OR VERY NEAR
THE MIN. AUTUMN READING OF -18C AT 850 MB AT ILN/DAY HAS ONLY
HAPPENED ONCE IN THE SOUNDING DATA CLIMATOLOGY ON OR BEFORE
NOVEMBER 19TH HAS ONLY HAPPENED ONE TIME /12Z ON NOVEMBER 13
1986 -- -19.3C/. WITH 500MB HEIGHTS/850MB TEMPS BOTH APPROACHING
BUT JUST FALLING SHY OF 3 SIGMA BELOW CLIMO...WE PROBABLY SHOULD
CONSIDER THE POTENTIAL FOR RECORD TYING/BREAKING TEMPS IN ONE OR
MORE OF THESE PERIODS. FOR RIGHT NOW GIVEN WE/RE STILL 5 DAYS
AWAY...WILL FOCUS ON TUESDAY MAX TEMPS GIVEN THIS IS WHEN CORE OF
COLDEST AIR PASSES OVERHEAD IN BASE OF THERMAL TROUGH. SO PUT TUES MAX
TEMPS RIGHT AT RECORD LOW MAX VALUES FOR RIGHT NOW AND WE CAN
EVALUATE FURTHER DROPS IF NEEDED. LOW CLOUDS IN LEE OF WARM GREAT
LAKES MAY KEEP RECORD MINS UNATTAINABLE AND PLAYING IT THIS WAY
RIGHT NOW AS RECORD LOWS ARE VERY COLD ON NOV 19TH. SOMETHING TO
WATCH...EITHER WAY...VERY CHILLY FOR MID NOV BUT OUTSIDE OF FLURRY
OR PERHAPS A SNOW SHOWER THREAT...MON/TUES SHOULD BE DRY.
STILL LOOKS LIKE THIS STRETCH WILL END UP VERY SIMILAR TO NOVEMBER
STRETCHES IN 1991...1996...AND 1997. ALL THREE OF THOSE YEARS HAD
8-9 DAY STRETCHES WHERE AVERAGE DAILY TEMPS FOR THE PERIOD WERE
NEAR 30F...AND ARE SOME THE CHILLIEST EARLY-MID NOVEMBER LONGER
DURATION PERIODS ON RECORD.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
MVFR/LOW VFR STRATOCUMULUS DECK IS TRYING TO ERODE AWAY FROM THE
WEST WITH SOME LOW LEVEL CLEARING WORKING ACROSS MUCH OF CENTRAL
INDIANA. LOWER CLOUDS ARE A LITTLE DIFFICULT TO MAKE OUT ON
SATELLITE GIVEN SOME OF THE MID LEVEL CLOUDS ALSO MOVING ACROSS
THE AREA...BUT IT DOES LOOK LIKE THE EASTWARD PROGRESSION OF THE LOWER
CLOUD CLEARING MAY HAVE SLOWED DOWN ON THE LAST COUPLE OF IMAGES.
MODELS ARE SUGGESTING A BIT OF A LOW LEVEL DRY WEDGE POSSIBLY
WORKING ACROSS THE AREA THROUGH LATE MORNING...BUT AM HESITANT TO
BACK AWAY FROM THE MVFR CIGS BASED ON THEIR PERSISTENCE SO FAR.
WILL GO AHEAD AND ALLOW THE CIGS TO LIFT UP INTO VFR THIS
AFTERNOON BUT CONTINUE TO LEAN PESSIMISTIC AND HANG ON TO AT LEAST
A BKN VFR CLOUD DECK THROUGH TONIGHT.
OUTLOOK...MVFR/IFR CEILINGS AND VISIBILITIES POSSIBLE SUNDAY INTO MONDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...BINAU
NEAR TERM...BINAU
SHORT TERM...BINAU
LONG TERM...BINAU
AVIATION...JGL
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
352 AM EST THU NOV 13 2014
.SYNOPSIS...
A PROLONGED PERIOD OF BELOW NORMAL TEMPERATURES WILL CONTINUE
THROUGHOUT MUCH OF NEXT WEEK AS A LARGE POOL OF UNSEASONABLY COLD
AIR REMAINS ENTRENCHED OVER THE EASTERN TWO THIRDS OF THE UNITED
STATES. SPRAWLING SURFACE HIGH PRESSURE WILL PROVIDE DRY WEATHER
THROUGH THE END OF THE WORK WEEK AND INTO THE FIRST HALF OF THE WEEKEND.
A COUPLE OF WEATHER SYSTEMS SHIFTING THROUGH THE TENNESSEE AND OHIO
VALLEYS SATURDAY NIGHT THROUGH SUNDAY NIGHT WILL BRING THE THREAT
OF SOME SNOW TO THE AREA...PERHAPS MIXING WITH OR CHANGING TO RAIN
ACROSS KENTUCKY AND SOUTHEAST OHIO ON SUNDAY AFTERNOON AND
EVENING. THE COLDEST AIR OF THE SEASON IS POISED TO MOVE INTO THE
AREA IN THE WAKE OF THESE SYSTEMS EARLY NEXT WEEK...WITH HIGHS
REMAINING BELOW FREEZING...AND LOWS IN THE TEENS AND BRISK WINDS.
&&
.NEAR TERM /THROUGH TONIGHT/...
RADAR MOSAICS THIS MORNING HAVE BEEN TRACKING A VERY NARROW BAND
OF LIGHT SNOW ACROSS CNTL/NRN IND STREAKING INTO NWRN OH. THIS
LINES UP VERY WELL WITH RAP/NAM 600MB FRONTOGENETIC FORCING ON THE
ANTICYCLONIC SHEAR SIDE OF NARROW/INTENSE 130KT JET RUNNING FROM
NRN IL INTO MI AND EVENTUALLY ONTARIO. THIS SEEN ON 1.5 PV SURFACE
/DYNAMIC TROPOPAUSE/. MAIN SHORTWAVE TROUGH/PV LOWERING IN THIS
FLOW IS APPROACHING CHICAGO AND IS TRANSLATING QUICKLY DOWNSTREAM
/NORTHEAST/ AND WILL BE NEAR DETROIT BY MIDDAY. MEANWHILE...LOW
LEVEL COLD ADVECTION CONTINUES AS LARGE ERN NOAM TROUGH CONTINUES
TO DEVELOP SWRD AND UPSTREAM 13.00Z RAOBS CONFIRM A HEALTHY/DEEP
SOURCE OF COLD AIR IN PLACE AND SHIFTING SLOWLY SOUTHEAST WITH
KILN /-9C AT 850MB/ GIVING WAY TO -11C TO -14C READINGS AT
KILX/KDTX/KGRB/KMPX. SAID RADAR MOSAICS ALSO SHOWING SLOWLY
GROWING LAKE-EFFECT SNOW SHOWERS/FLURRIES IN LEE OF WARM LAKE
MICHIGAN WATERS. 13.00Z KILN SOUNDING CONTINUED TO SHOW THIN /30
MB DEEP/ LAYER OF SATURATION WITH RESPECT TO ICE BETWEEN 850MB AND
880MB /ABOUT -10C/. GOES FOG PRODUCT CONFIRMS A LARGE AMOUNT OF
STRATUS ACROSS THE AREA BACK INTO MUCH OF INDIANA WHERE MID LVL
FGEN AND APPROACHING PV ANOMALY ARE PRODUCING THICKER/WIDESPREAD
CLOUD ATOP THE LARGE STRATUS SHIELD. SEEMS TO BE JUST ENOUGH
SEPARATION /5KFT/ BETWEEN MID LEVEL MOISTURE AND LOWER LEVEL
MOISTURE TO PREVENT MUCH IN THE WAY OF SEEDER FEEDER FROM THE MID
DECK TO THE LOWER CLOUD AS IT CROSSES THE CWA THIS MORNING.
SO...CONSIDERED RUNNING A FLURRY MENTION ESP THIS MORNING ACROSS
WCNTL/CNTL OHIO AS WEAKENING BAND OF FGEN FORCING SLIDES
EAST/NORTHEAST ACROSS NORTHERN HALF OF OHIO. STILL MAY DO AT SOME
POINT IN THE NEXT FEW HOURS OF RADAR EVAL BUT FOR RIGHT NOW NOT
SEEING ENOUGH TO MENTION. AM REMAINING PESSIMISTIC ON CLOUDS
TODAY...GOING MOSTLY CLOUDY MOST AREAS. WITH MOISTURE SO
THIN...AND OVERALL PROFILE BECOMING QUITE SUBSIDENT IN THE WAKE OF
THE WAVE/FORCING THIS MORNING...SOME HOLES COULD BE CHEWED IN THE
STRATUS ESP THIS AFTN BUT CONSIDERING ITS NOVEMBER...SUBSIDENCE
INVERSION NOT GOING AWAY...AND CAA/LAKE MICHIGAN FEED OF RH IS
PRESENT ON MOST NWP SOLUTIONS...WILL JUST RIDE THE CLOUDS UNTIL WE
SEE MORE SUBSTANTIAL EROSION. 1000-850MB THICKNESS DERIVED
EQUATIONS FROM ILN SOUNDING DATA SUGGEST HIGH TEMPS SHOULD BE A
FEW DEGREES COLDER THAN PVS FORECAST...SO STARTED WITH THIS BUT
NUDGED BACK TO BLENDED MOS WHICH GAVE HIGHS IN THE LOWER/MID 30S
MOST AREAS. IF CLOUDS REMAIN THICK ALL DAY...LOWER SIDE OF THIS
ENVELOPE IS EXPECTED. LATEST HIGHER RES NAM-WRF AND EVEN TO A
DEGREE GFS DATA SUGGESTING 900-800MB RH WILL REMAIN HIGH OR EVEN
INCREASE TONIGHT AS COLD ADVECTION CONTINUES WITH -14C 850MB POOL
ROTATING EAST RIGHT ACROSS THE CWA TONIGHT. DESPITE SUBSIDENCE
THAT CONTINUES TO INCREASE...WILL ONLY ALLOW FOR A VERY SLOW
EROSION OF CLOUDS AND IT MAY VERY WELL REMAIN MOSTLY CLOUDY
THROUGH THE NIGHT AS WELL. FOR THIS REASON...KEEPING MIN TEMPS ON
THE WARM SIDE OF STATISTICAL MOS. AT SOME POINT MAY NEED TO
MENTION A FLURRY OR LIGHT SNOW SHOWER REMAINING INTACT ALL THE WAY
FROM LAKE MICHIGAN INTO AREAS NORTH OF I-70 /REF VERY WEAK
SIMULATE REFLECTIVITY ON RECENT HRRR RUNS INTO AUGLAIZE/HARDIN
COUNTIES/
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY/...
THIS A QUIET...COLD PERIOD. POOL OF -14C /850MB/ AIR ONLY VERY
SLOWLY MODIFIES ON FRIDAY...WITH VERY SIMILAR 925MB TEMPS AS ON
THURSDAY...SO KEEPING HIGH TEMPS VERY SIMILAR TO FRIDAY WITH
EMPHASIS ON RELATIVELY HIGHER TERRAIN AREAS THE COOLEST AND
WARMEST OVER IN THE SCIOTO VALLEY. AM BANKING ON MORE SUNSHINE ON
FRIDAY ESPECIALLY THE FURTHER SOUTH ONE GOES IN THE ILN FORECAST
AREA...GIVEN TRAJECTORIES OF LOW LEVEL FLOW OFF LAKE MICHIGAN
FOCUSING THE BETTER STREAMERS OF LAKE EFFECT CLOUDS INTO AREA
ALONG/NORTH OF I-70. THAT BEING SAID...PESKY SUBSIDENCE INVERSION
REMAINS ON 13.00Z NAM/GFS SOUNDINGS INTO FRIDAY AFTERNOON WITH
STRONG DEEP TROPOSPHERIC SUBSIDENCE SIGNAL ALOFT. PLENTY OF RH ON
FCST SOUNDINGS...BUT NOT AS MUCH AS THURSDAY...SO THINKING AT
LEAST PARTLY CLOUDY SHOULD WORK BY AFTERNOON MOST AREAS. WE ALWAYS
SEEM TO UNDERESTIMATE HOW LONG THE LOW CLOUDS HANG IN THESE FLOW
REGIMES...SO LOWER CONFIDENCE HERE. AS MENTIONED IN PREVIOUS
DISCUSSIONS...A CHANCE WE COULD TIE OR BARELY BREAK A RECORD LOW
MAXIMUM TEMP RECORD ON FRIDAY...ONLY BECAUSE FRIDAY/S VALUES ARE A
NOTICEABLE BUBBLE OF WARMTH IN THE PERIOD OF RECORD IN COMPARISON
WITH DAYS AROUND IT. CMH /34 DEGREES IN 1916/ HAS THE GREATEST
POTENTIAL FOLLOWED BY 32 DEGREES /CVG IN 1916/ AND DAYTON /31
DEGREES IN 1916/.
IF A GOOD CLEARING TREND DOES OCCUR FRIDAY NIGHT...APPROACH AND
PASSAGE OF 1032MB SURFACE HIGH ACROSS SRN OH AND KENTUCKY SHOULD
MEAN LIGHT WINDS OVERNIGHT AND POTENTIAL FOR GOOD TEMP DROP.
CONTINUE TO MENTION MID/UPPER TEENS MOST AREAS WITH A BIAS
CORRECTION INFLUENCE ON THE TEMP GRID TO BRING OUT THE RELATIVE
WARM/COOL SPOTS. WOULD NOT BE AT ALL SURPRISED TO SEE SOME OF THE
REAL NOOKS AND CRANNIES PRONE TO COLD AIR SEEPAGE DROP DOWN IN THE
LOWER TEENS IF SKIES GO CLEAR EARLY IN THE NIGHT.
QUIET WEATHER CONTINUES INTO SATURDAY. SYSTEMS WE WILL NEED TO
START WATCHING FOR LATER IN THE WEEKEND /SEE MORE IN LONG TERM
DISCUSSION BELOW/ WILL BE 1) DIGGING SOUTHWARD THROUGH NRN
ROCKIES...DOWN THE BACKSIDE OF ANOMALOUS WRN CANADA
ANTICYCLONE...AND 2) WEAKER WAVE OVER THE FOUR CORNERS. FLOW OVER
THE OHIO VALLEY WILL BE BACKING AND FLATTENING IN THE BASAL
PORTION OF THE MASSIVE LONGWAVE TROUGH...AND DESPITE SOME RATHER
DECENT MID LEVEL HEIGHT RISES DURING THE DAY ON SATURDAY...LOW
LEVEL TEMPS WILL BE SLOWER TO RESPOND. DUE TO WEAK
TRAJECTORIES/POOR MIXING ON BACKSIDE OF STRONG SURFACE HIGH
PUSHING SOUTHEAST OF AREA. LIKELY TO BE AN INCREASE IN CIRRUS SAT
AFTN AND WHATEVER REMNANT LOW CLOUDS MAY STILL BE HANGING
AROUND...BUT THIS DAY PROBABLY HAS THE POTENTIAL OF A GOOD AMOUNT
OF SUNSHINE...WHICH WILL ALLOW TEMPS BACK INTO THE MID/UPPER 30S.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
WEAK WAVE OVER THE FOUR CORNERS SATURDAY MORNING WILL BE EJECTED
QUICKLY ON FAST WLY FLOW THROUGH THE BASE OF L/W TROUGH INTO THE
OHIO VALLEY SAT NIGHT. MOISTURE STARVED...WEAK VERTICAL MOTION
SUGGESTS A CONTINUED LOW/MID RANGE MENTION OF LIGHT SNOW CHANCES
LATER SATURDAY NIGHT. HAVE SLOWED DOWN THE MENTION OF SNOW A
LITTLE FROM PREVIOUS FORECAST. INCREASING/THICKENING CLOUDS SAT
NIGHT SHOULD KEEP LOWS A GOOD DEAL WARMER ON SAT NIGHT IN
COMPARISON TO FRI NIGHT.
WAVE OF INTEREST THOUGH WILL ITSELF BE DIGGING THROUGH THE FOUR
CORNERS BY SUNDAY MORNING SET TO EJECT QUICKLY EAST...THOUGH AT A
LOWER LATITUDE WITH IT BEING STRONGER AND A DEEPER DIG THROUGH THE
L/W TROUGH. THIS WAVE WILL BEGIN TO PHASE WITH AN EVEN STRONGER
SHORTWAVE DIGGING SOUTHEAST THROUGH THE WESTERN GREAT LAKES ON
SUNDAY AFTERNOON...WHICH IN AN OVERALL SENSE GREATLY
AMPLIFIES/SHARPENS THE LONGWAVE TROUGH. WEIGHTED GFS PROGS FOR
SUNDAY/MONDAY HAVE SHOWN A STRONG AMPLIFICATION SIGNAL IN RUN-
0VER-RUN SENSE WITH THIS DEEPENING UPPER TROUGH WITH LOWERING
HEIGHTS IN THE BASE OF THE TROUGH AND INCREASING HEIGHTS W/TIME ON
BOTH UPSTREAM AND DOWNSTREAM RIDGES. IN RESPONSE...PRESSURES WILL
FALL WELL DOWNSTREAM OF THIS PHASING OVER THE GULF COAST INTO THE
APPALACHIANS SUNDAY AFTN/NIGHT WITH MOISTURE ADVECTION IN THE MID
LEVELS TAKING PLACE AND INCREASING DEFORMATION/FGEN FORCING ON THE
WEST SIDE OF THE APPALACHIANS INCLUDING OHIO/IND/KY. THIS SHOULD
PROMOTE A NEWRD TRANSLATING BAND OF PCPN THROUGH KENTUCKY INTO
OHIO/WV SUNDAY AND SUNDAY NIGHT. DPROG/DT TRENDS STILL JUMPY OVER
THE LAST 24 HOURS...BUT SOME CONSENSUS STARTING TO BE SEEN WITH
12.12Z GFS AND 13.00Z GFS LOOKING SIMILAR...WHICH IS A TREND TO
12.00Z AND 12.12Z ECMWF SHOWING PRECIPITATION FOCUSING IN ERN HALF
OF CWA WITH POTENTIAL FOR LIGHT ACCUMULATING SNOWS. DETERMINISTIC
GFS /PARALLEL AND OPNL/ CONTINUE TO BE COLDER THAN ECMWF WITH ALL
SNOW SCENARIO...WHILE RECENT ECMWF RUNS VERY STABLE IN SUGGESTING
PERHAPS A RAIN/SNOW POTENTIAL IN OUR FAR SOUTHERN/EASTERN AREAS.
INCREASED PCPN CHANCES BRINGING LIKELY CHANCES BACK TO CVG/ILN/CMH
AND BLENDED THERMAL PROFILES OF COLDER GFS/WARMER ECMWF TO ARRIVE
AT PTYPE. 12.18Z GEFS PROBS SUPPORT THE LIKELY POPS IN OUR
SOUTH/EAST AT THIS TIME RANGE...AND THERE IS ACKNOWLEDGMENT THAT
IF NEW 12Z DETERMINISTIC ECMWF/GFS CONTINUE TO STABILIZE THAT
HIGHER CHANCES OF PCPN WILL BE NEEDED CWA-WIDE THOUGH THERE IS A
TIGHT GRADIENT IN OUR WEST AS OF NOW. POTENTIAL FOR LIGHT SNOW
ACCUMULATIONS FOR MANY ON SUN/SUN NIGHT. MOST CONSENSUS FOCUS
RIGHT NOW IS EAST OF I-71.
SYSTEM PUSHES EAST MONDAY WITH CORE OF COLDEST AIR IN THIS PATTERN
DROPPING SOUTH AND THEN EAST RIGHT ACROSS THE CWA MON NIGHT AND
TUES. 850MB TEMPS TO -18C SEEMS LIKELY...WHICH PUTS US AT VERY
EDGE OF THE ENVELOPE IN TERMS OF THE CLIMO SPECTRUM SEEN IN BOTH
GEFS AND NAEFS REFORECAST PERCENTILES...MEANING FOR WHAT IS BEING
FORECAST BY THE ENSEMBLE SYSTEMS AT THIS TIME RANGE IS UNUSUAL TO
BE THIS DEEP/COLD WITH THE UPPER TROUGH. M-CLIMATE NUMBERS /GEFS/ AND
REFORECAST PERCENTILES /NAEFS/ ARE EITHER AT THEIR MINS OR VERY NEAR
THE MIN. AUTUMN READING OF -18C AT 850 MB AT ILN/DAY HAS ONLY
HAPPENED ONCE IN THE SOUNDING DATA CLIMATOLOGY ON OR BEFORE
NOVEMBER 19TH HAS ONLY HAPPENED ONE TIME /12Z ON NOVEMBER 13
1986 -- -19.3C/. WITH 500MB HEIGHTS/850MB TEMPS BOTH APPROACHING
BUT JUST FALLING SHY OF 3 SIGMA BELOW CLIMO...WE PROBABLY SHOULD
CONSIDER THE POTENTIAL FOR RECORD TYING/BREAKING TEMPS IN ONE OR
MORE OF THESE PERIODS. FOR RIGHT NOW GIVEN WE/RE STILL 5 DAYS
AWAY...WILL FOCUS ON TUESDAY MAX TEMPS GIVEN THIS IS WHEN CORE OF
COLDEST AIR PASSES OVERHEAD IN BASE OF THERMAL TROUGH. SO PUT TUES MAX
TEMPS RIGHT AT RECORD LOW MAX VALUES FOR RIGHT NOW AND WE CAN
EVALUATE FURTHER DROPS IF NEEDED. LOW CLOUDS IN LEE OF WARM GREAT
LAKES MAY KEEP RECORD MINS UNATTAINABLE AND PLAYING IT THIS WAY
RIGHT NOW AS RECORD LOWS ARE VERY COLD ON NOV 19TH. SOMETHING TO
WATCH...EITHER WAY...VERY CHILLY FOR MID NOV BUT OUTSIDE OF FLURRY
OR PERHAPS A SNOW SHOWER THREAT...MON/TUES SHOULD BE DRY.
STILL LOOKS LIKE THIS STRETCH WILL END UP VERY SIMILAR TO NOVEMBER
STRETCHES IN 1991...1996...AND 1997. ALL THREE OF THOSE YEARS HAD
8-9 DAY STRETCHES WHERE AVERAGE DAILY TEMPS FOR THE PERIOD WERE
NEAR 30F...AND ARE SOME THE CHILLIEST EARLY-MID NOVEMBER LONGER
DURATION PERIODS ON RECORD.
&&
.AVIATION /08Z THURSDAY THROUGH MONDAY/...
THE SOLID STRATOCUMULUS DECK REMAINS IN PLACE ACROSS THE REGION EARLY
THIS MORNING. IT HAS BEEN TRYING TO ERODE EVER SO SLOWLY BACK TO OUR
SOUTHWEST ACROSS SOUTHERN ILLINOIS AND FAR WESTERN KENTUCKY.
MODELS CONTINUE TO HAVE A DIFFICULT TIME HANDLING THESE LOWER
CLOUDS BUT GIVEN THE TREND OF THE PAST DAY OR SO AND THE FACT
THAT AT LEAST SOME WEAK LOW LEVEL CAA WILL PERSIST THROUGH THE
DAY...WILL HANG ON TO THE CLOUDS THROUGH THIS AFTERNOON. THE
CLOUD DECK HAS BEEN FLUCTUATING BETWEEN HIGH MVFR AND LOW VFR BUT
AS WE PROGRESS THROUGH THE EARLY MORNING HOURS...WOULD EXPECT A
BIT OF A LOWERING INTO A MORE CONSISTENT MVFR DECK BEFORE LIFTING
BACK UP INTO VFR THIS AFTERNOON.
OUTLOOK...MVFR/IFR CEILINGS AND VISIBILITIES POSSIBLE SUNDAY INTO MONDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...BINAU
NEAR TERM...BINAU
SHORT TERM...BINAU
LONG TERM...BINAU
AVIATION...JGL
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
1235 AM EST THU NOV 13 2014
.SYNOPSIS...
A PROLONGED PERIOD OF BELOW NORMAL TEMPERATURES WILL CONTINUE
THROUGHOUT MUCH OF NEXT WEEK AS A LARGE POOL OF UNSEASONABLY COLD
AIR BECOMES ENTRENCHED OVER THE EASTERN TWO THIRDS OF THE UNITED
STATES. SPRAWLING SURFACE HIGH PRESSURE WILL PROVIDE DRY WEATHER
THROUGH THE END OF THE WEEK AND INTO THE WEEKEND. A WEATHER SYSTEM
SHIFTING THROUGH ON SUNDAY AND SUNDAY NIGHT WILL BRING THE THREAT
OF SOME SNOW TO THE AREA...PERHAPS MIXING WITH OR CHANGING TO RAIN
ACROSS KENTUCKY AND SOUTHEAST OHIO.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
A PERSISTENT STRATOCUMULUS DECK (2500-3500 FEET) IS EXPECTED TO
REMAIN IN PLACE OVERNIGHT. RECENT GFS/NAM RUNS HAVE NOT SEEMED TO
CAPTURE THIS LAYER OF RH VERY WELL (THE 00Z NAM WAS A SLIGHT
IMPROVEMENT)...BUT THE 01Z RAP IS IN GOOD SHAPE WITH SATURATION
INDICATED AT 900MB. THE RAP/HRRR WERE USED AS GUIDANCE FOR SOME
SLIGHT UPWARD ADJUSTMENTS TO THE MIN TEMP AND SKY COVER
FORECASTS...WITH THE EXPECTATION THAT MOST CLOUDS SHOULD REMAIN IN
PLACE THROUGH MORNING.
PREVIOUS DISCUSSION >
COLD WEATHER PATTERN WITH TEMPERATURES 15 TO 20 DEGREES BELOW
NORMAL. BROAD MEAN TROF WITH AN ELONGATED CENTERED ORIENTED E-W
FROM THE NRN PLAINS THRU THE GREAT LAKES. DUMBBELL EFFECT TO TAKE
PLACE AS INITIAL S/W PIVOTS INTO SE CANADA THE NEXT WESTERN S/W
AXIS TO WORK INTO THE UPR MS VLY TONIGHT. SFC HIGH PRESSURE OF
ARCTIC ORIGIN TO SLOWLY BUILD SOUTH INTO THE CENTRAL PLAINS AND
NOSE INTO THE OHIO VALLEY. ILN/S 12Z SOUNDING SHOWED MOISTURE
AROUND 900 MB TRAPPED BELOW A STRONG SUBSIDENCE INVERSION. LATEST
VISIBLE SATL IMGRY SHOWS CLOUD COVER OVER OHIO BACK THRU INDIANA
INTO ILLINOIS. SOME HOLES DEVELOPED IN THIS SHALLOW MOISTURE BUT
LATEST SATL TRENDS SHOWING THESE HOLES FILLING IN. 12Z GFS SOLN IS
TOO QUICK WITH DRYING AND PREVIOUS RUN WAS ALREADY NOT VERIFYING
WELL. NAM SOLN HOLDS ONTO MOISTURE LONGER...PERHAPS ONLY ALLOWING
A FEW MORE BREAKS INTO THE SW LATE. IN LOW LEVEL CAA PATTERN DO
NOT EXPECT QUICK CLEARING AT NIGHT. WILL LEAN TOWARD HOLDING ONTO
THE CLOUDS LONGER AND ADJUST THE SKY GRIDS ACCORDINGLY. OVERNIGHT
LOWS WILL BE COLD...RANGING FROM THE MID 20S WEST TO THE UPPER 20S
EAST.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH FRIDAY NIGHT/...
BROAD MID/UPR LEVEL TROF OVER THE GREAT LAKES WITH UPSTREAM
S/W TO ROTATE SE. ASSOCIATED SHEARED VORT AXIS TO MOVE THRU THE
REGION THURSDAY. SOME MID/UPPER LEVEL FORCING WITH THIS
FEATURE ON THURSDAY. A SNOW SHOWER OR FLURRY IS NOT OUT OF THE
QUESTION...ESPECIALLY ACROSS THE NORTH. NO SIGNIFICANT LOW LEVEL
FORCING AND DRY LAYER BETWEEN MID CLOUDS AND LOWER CLOUDS LEANS
TOWARD A DRY SOLN. CLOUD COVER AND LOW LEVEL CAA WILL KEEP
TEMPERATURES FROM RISING MUCH ON THURSDAY. EXPECT HIGHS ABOUT 20
DEGREES BELOW NORMAL...RANGING FROM THE LOWER 30S NORTHWEST TO THE
UPPER 30S SE.
EXPECT ONLY SOME PARTIAL CLEARING THURSDAY NIGHT...WITH THE BEST
CHANCE ACRS THE SW. OVERNIGHT LOWS GENERALLY EXPECTED TO BE IN THE
LOWER 20S BY FRIDAY MORNING.
THE CENTER OF THE ARCTIC HIGH PRESSURE TO BUILD INTO THE MS VLY
FRIDAY AND OVER THE OHIO VALLEY FRIDAY NIGHT. EXPECT SOME EROSION
OF THE CLOUDS FROM THE SW FRIDAY AND THEN BETTER CHANCE FOR CLEARING
FRIDAY NIGHT WITH THE HIGH BUILDING IN. COLD HIGHS ON FRIDAY IN
THE LOWER/MIDDLE 30S. FRIDAY NIGHT LOOKS TO BE THE COLDEST NIGHT
OF THE SHORT TERM WITH LIGHT WINDS AND DIMINISHING CLOUDS. LOWS EXPECTED
TO RANGE FROM THE UPPER TEENS TO THE LOWER 20S.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
HIGH PRESSURE AND A DRY AIRMASS WILL BE PUSHING EAST EARLY SATURDAY.
SHORT WAVE ENERGY AND LIMITED MOISTURE TRAVELING THROUGH THE GREAT
LAKES WILL BRING A CHANCE OF SNOW SHOWERS SATURDAY NIGHT.
MOISTURE AND ENERGY ARRIVING ON A SOUTHWEST UPPER FLOW MAY RESULT IN
MORE SNOW SHOWERS SUNDAY AND MONDAY. DUE TO MODEL DIFFERENCES...
TIMING AND AMOUNTS OF PRECIP ARE UNCERTAIN AT THIS POINT. THERMAL
PROFILES INDICATE RAIN IN SOUTHERN LOCATIONS MONDAY AFTERNOON.
FOR TUESDAY AND WEDNESDAY...HIGH PRESSURE AND A LACK OF MOISTURE
SHOULD PRODUCE DRY WEATHER.
WELL BELOW NORMAL 500 MB HEIGHTS ARE IN STORE THROUGH THE PERIOD.
COUPLED WITH A LOW LEVEL FLOW CARRYING COLDER AIR FROM THE
NORTH...TEMPERATURES WILL BE FAR BENEATH SEASONAL AVERAGES. HIGHS
MAINLY IN THE 30S SATURDAY THROUGH MONDAY WILL BE FOLLOWED BY EVEN
COLDER READINGS IN THE UPPER 20S ON TUESDAY BEFORE REBOUNDING BACK
TO THE 30S FOR WEDNESDAY. THIS COMPARES TO NORMAL HIGHS IN THE LOWER
50S.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
THE SOLID STRATOCUMULUS DECK REMAINS IN PLACE ACROSS THE REGION EARLY
THIS MORNING. IT HAS BEEN TRYING TO ERODE EVER SO SLOWLY BACK TO OUR
SOUTHWEST ACROSS SOUTHERN ILLINOIS AND FAR WESTERN KENTUCKY.
MODELS CONTINUE TO HAVE A DIFFICULT TIME HANDLING THESE LOWER
CLOUDS BUT GIVEN THE TREND OF THE PAST DAY OR SO AND THE FACT
THAT AT LEAST SOME WEAK LOW LEVEL CAA WILL PERSIST THROUGH THE
DAY...WILL HANG ON TO THE CLOUDS THROUGH THIS AFTERNOON. THE
CLOUD DECK HAS BEEN FLUCTUATING BETWEEN HIGH MVFR AND LOW VFR BUT
AS WE PROGRESS THROUGH THE EARLY MORNING HOURS...WOULD EXPECT A
BIT OF A LOWERING INTO A MORE CONSISTENT MVFR DECK BEFORE LIFTING
BACK UP INTO VFR THIS AFTERNOON.
OUTLOOK...MVFR/IFR CEILINGS AND VISIBILITIES POSSIBLE SUNDAY INTO MONDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...AR
NEAR TERM...HATZOS/AR
SHORT TERM...AR
LONG TERM...CONIGLIO
AVIATION...JGL
AREA FORECAST DISCUSSION...UPDATED
NWS NORMAN OK
719 PM CST FRI NOV 14 2014
.UPDATE...
ADJUSTED PRECIPITATION TYPE ACROSS NORTHERN OKLAHOMA AFTER
MIDNIGHT TONIGHT THROUGH EARLY SATURDAY AFTERNOON TO INCLUDE
SLEET.
&&
.DISCUSSION...
A LIGHT WINTRY MIX OF MAINLY LIGHT SLEET AND LIGHT SNOW
IS POSSIBLE AFTER MIDNIGHT TONIGHT THROUGH 3 PM SATURDAY
ACROSS NORTHERN OKLAHOMA.
LATEST HRRR RUNS HAVE BEEN DEPICTING LIGHT PRECIPITATION
DEVELOPING AS LIFT INCREASES IN NORTHWEST OKLAHOMA MIDNIGHT TO
4 AM TONIGHT...THEN SPREADING EAST...AFFECTING AREAS NORTH OF A
GAGE TO STILLWATER LINE. FORECAST PRECIPITATION CHANCES ARE IN
GOOD SHAPE AND WERE NOT ALTERED.
BASED ON THE LATEST 00Z NEARBY UPPER AIR SOUNDINGS AND TOP DOWN
SOUNDING METHODOLOGY...BELIEVE ANY PRECIPITATION REACHING THE
GROUND WOULD MAINLY BE LIGHT SLEET AS PRECIPITATION ALOFT WOULD
PARTIALLY OR COMPLETELY MELT WITH A 720-800 MB WARM NOSE OF +1 TO
+6C THEN REFREEZE 800-850 MB WITH TEMPERATURES AROUND -9C.
LIGHT SNOW WOULD BE POSSIBLE IF PRECIPITATION INTENSITY BECOMES
HEAVY ENOUGH TO ALLOW EVAPORATIONAL COOLING TO ERODE THE MID
LEVEL WARM NOSE. LATEST RAP13 RUNS HINT THAT THIS COULD OCCUR
NORTH OF AN ALVA TO STILLWATER LINE AFTER 4 AM TONIGHT.
REGARDLESS OF PRECIPITATION TYPE...ANY PRECIPITATION AMOUNTS
APPEAR TO BE LIGHT IN NORTHERN OKLAHOMA WITH THE HEAVIER AMOUNTS
FARTHER NORTH ACROSS NORTHERN KANSAS LATE TONIGHT INTO SATURDAY.
COULD NOT COMPLETELY RULE OUT A DUSTING OF SLEET OR SNOW
ACCUMULATIONS MIDNIGHT TONIGHT TO 3 PM SATURDAY OVER NORTHERN
OKLAHOMA...BUT THINK IMPACTS WILL BE MINIMAL DUE TO THE LIGHT
NATURE OF PRECIPITATION AND LACK OF SIGNIFICANT NEARBY MOISTURE.
HOWEVER...WITH SURFACE TEMPERATURES BELOW FREEZING...A FEW SLICK
SPOTS COULD DEVELOP.
WILL CONTINUE TO MONITOR. PRODUCTS HAVE BEEN UPDATED. NO WINTER
WEATHER ADVISORIES ARE EXPECTED TO BE ISSUED FOR TONIGHT THROUGH
SATURDAY AFTERNOON AT THIS TIME.
MBS
&&
.PREV DISCUSSION... /ISSUED 542 PM CST FRI NOV 14 2014/
DISCUSSION...
AVIATION DISCUSSION FOR THE 00Z TAFS IS BELOW.
AVIATION...
OVERALL...VFR CONDITIONS ARE EXPECTED TO CONTINUE.
A LIGHT WINTRY MIX OF PRECIPITATION IS POSSIBLE NORTH OF KCSM-
KOKC 06-18Z. KEPT PROB30 GROUP FOR MVFR CONDITIONS AND -SN AT KPNC
12-17Z WHERE CONFIDENCE IS MODERATE. OTHERWISE...CONFIDENCE OF
PRECIPITATION OCCURRENCE IS TOO LOW TO MENTION.
SOUTH WINDS WILL BE BECOME GUSTY AT MANY SITES 12-16Z...THEN
DIMINISH 20-24Z. A COLD FRONT WILL BRING A WIND SHIFT TO THE
NORTH NEAR KWWR AND KGAG AFTER 21Z.
MBS
PREV DISCUSSION... /ISSUED 255 PM CST FRI NOV 14 2014/
DISCUSSION...
SHORT TERM...(TONIGHT-SUNDAY NIGHT)
LOW CLOUDS SHOULD CONTINUE TO ERODE THROUGH THE AFTERNOON
WHILE HIGH CLOUDS SLOWLY INCREASE. A QUICK MOVING SYSTEM WILL
APPROACH TONIGHT AND SHOULD CLEAR THE SOUTHERN PLAINS BY SATURDAY
AFTERNOON. THE OVERALL TREND WITH THIS SYSTEM...HAS BEEN BETTER
CHANCES FOR PRECIPITATION MAINLY NORTH OF OKLAHOMA. WILL KEEP LOW
CHANCES FOR LIGHT SNOW ACROSS NORTHERN OKLAHOMA FROM LATE TONIGHT
THROUGH LATE SATURDAY MORNING. A WARM NOSE BELOW 7H ACROSS
NORTHWEST OKLAHOMA MAY RESULT IN SOME SLEET OVERNIGHT.
PRECIPITATION AMOUNTS WILL BE LIGHT WITH THIS SYSTEM.
ANOTHER PUSH OF RATHER COLD AIR WILL BEGIN TO ENTER NORTHWEST
OKLAHOMA LATE SATURDAY AFTERNOON AND EVENING. GUSTY NORTHERLY
WINDS CAN BE EXPECTED ACROSS MOST OF OKLAHOMA BY EARLY/MID
SUNDAY MORNING. AN APPROACHING WAVE WILL BRING A DECENT CHANCE
OF LIGHT SNOW SUNDAY MORNING AND AFTERNOON. MOST MODELS INDICATE
THE BEST LIFT OCCURRING ACROSS NORTHERN OKLAHOMA SUNDAY MORNING
THEN SHIFTING SOUTHWARD DURING THE AFTERNOON. A LITTLE UNSURE ON
AMOUNTS...BUT EXPECT SOME AREAS NORTH OF OF I-40 SHOULD SEE AN
INCH OF SNOW WITH 2 INCH AMOUNTS POSSIBLE. WITH THE RECENT COLD
WEATHER...ANY SNOW THAT FALLS WILL ACCUMULATE AND MAY CAUSE MINOR
TRAFFIC DELAYS.
LONG TERM...(MONDAY-THURSDAY)
A GRADUAL WARMING TREND WILL BEGIN EARLY NEXT WEEK, WITH SURFACE
WINDS BECOMING SOUTHERLY BY MIDWEEK. AN UPPER WAVE WILL MOVE
ACROSS THE AREA ON THURSDAY, BRINGING LOW POPS FOR RAIN ACROSS
SOUTHEAST OKLAHOMA. THE COLD FRONT ASSOCIATED WITH THIS SYSTEM
APPEARS TO BE WEAK, STALLING ACROSS NORTHWEST OKLAHOMA BEFORE
LIFTING BACK TO THE NORTH.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 27 46 27 29 / 0 20 10 50
HOBART OK 28 48 27 29 / 10 10 10 40
WICHITA FALLS TX 29 53 32 33 / 0 10 10 30
GAGE OK 25 42 20 29 / 20 10 30 60
PONCA CITY OK 25 41 24 29 / 10 30 20 60
DURANT OK 28 45 34 39 / 0 10 20 30
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
04/17
AREA FORECAST DISCUSSION...UPDATED
NWS NORMAN OK
1206 AM CST THU NOV 13 2014
.AVIATION...06Z TAF ISSUANCE...
VFR CONDITIONS WILL PREVAIL THROUGH THE PERIOD. OVC MID LEVEL
CLOUDS WILL PERSIST THROUGH MUCH OF THE PERIOD... SLIGHTLY
IMPROVING THROUGH THE AFTN FROM N-S. GUSTY NORTH WINDS WILL
PERSIST THROUGH 18Z... WITH WINDS RELAXING THROUGH THE LATE
AFTERNOON AND EVENING.
JTK
&&
.PREV DISCUSSION... /ISSUED 1011 PM CST WED NOV 12 2014/
UPDATE...
ADJUSTED PRECIP/WX FOR OVERNIGHT.
DISCUSSION...
WATCHING RADAR/OBS TRENDS CLOSELY... LIGHT AREA OF SNOW LOOKS TO
BE PERSISTING JUST NORTH/ALONG THE OK/KS BORDER. RECENT HRRR
DISPENSES WITH THIS AREA QUICK THROUGH 13/04Z... WHILE 13/00Z NAM
SWEEPS SOME LIGHT PRECIP ACROSS NWRN OK TONIGHT. GIVEN WEAK
OVERALL FORCING... WILL STICK WITH THE RADAR/OBS TRENDS. DDC WENT
DOWN TO 2 1/2 MILES VIS EARLIER...8-9PM... AS THE BAND SLID
THROUGH. OTHER THAN A QUICK DROP IN VIS ACROSS FAR NWRN OK...
LITTLE TO NO IMPACTS ARE EXPECTED AS THIS BAND FINALLY DISSIPATES
IN 2-3HRS.
JTK
PREV DISCUSSION... /ISSUED 758 PM CST WED NOV 12 2014/
UPDATE...
LOWERED MIN TEMPS IN THE NORTHWEST. INCREASED CLOUD COVER
OVERNIGHT. ADJUSTED WINDS TO MORE ACCURATELY REFLECT CURRENT
OBSERVATIONS.
DISCUSSION...
TEMPERATURES IN THE NORTHWEST WERE DROPPING FASTER THAN PREVIOUSLY
FORECAST. THE HRRR SHOWS TEMPS IN THAT REGION FALLING INTO THE
LOWER TEENS.
SKIES ARE CURRENTLY OVERCAST...AND CLOUDS ARE NOT EXPECTED TO
BREAK ANY TIME SOON.
GUSTY WINDS ARE STILL HOLDING ON...BUT ARE STILL EXPECTED TO DIE
DOWN LATER TONIGHT.
PREV DISCUSSION... /ISSUED 250 PM CST WED NOV 12 2014/
DISCUSSION...
ARCTIC AIR WILL REMAIN IN PLACE OVER THE NEXT FEW DAYS AS A POLAR
HIGH SLOWLY SETTLES INTO THE CENTRAL AND SOUTHERN PLAINS. A
COMPACT UPPER WAVE HAS LEAD TO WIDESPREAD CLOUDS AND EVEN A FEW
SNOW SHOWERS OVER PARTS OF THE TX PANHANDLE/SOUTHWEST OK THIS
AFTERNOON. A FEW SNOW FLURRIES MAY FALL IN ISOLATED AREAS THROUGH
TONIGHT...BUT NO SIGNIFICANT IMPACTS ARE EXPECTED.
COLD WEATHER WILL PREVAIL THROUGH THE COMING WEEKEND. THIS MAY
SET THE STAGE FOR OUR FIRST TASTE OF WINTRY PRECIPITATION AS A
SERIES OF UPPER LEVEL STORMS MOVE ACROSS THE SOUTHERN PLAINS
WITHIN A PERSISTENT COLD AIRMASS. THE FIRST SYSTEM WILL AFFECT THE
REGION DURING THE DAY ON SATURDAY. SNOW OR A MIXTURE OF RAIN AND
SNOW MAY OCCUR OVER NORTHERN OKLAHOMA EARLY SATURDAY...WITH RAIN
ELSEWHERE. SOUTHERLY FLOW AND MID-LEVEL DRY AIR SHOULD ALLOW HIGHS
TO ECLIPSE FREEZING OVER MUCH OF THE AREA BY NOON
SATURDAY...RESULTING IN A TRANSITION TO MAINLY RAIN MUCH OF
SATURDAY AFTERNOON AND EVENING...AND LITTLE IF ANY ACCUMULATION OF
FROZEN PRECIPITATION IS EXPECTED SATURDAY. A SECOND MORE POTENT
STORM WILL ARRIVE SATURDAY NIGHT AND SUNDAY ON THE HEELS OF A
SECOND SHOT OF ARCTIC AIR. AS THE FRONT SHIFTS SOUTHWARD...A DEEP
COLD AIRMASS WILL SETTLE INTO THE PLAINS. AS FRONTOGENETIC FORCING
INCREASES SUNDAY AND SUNDAY AFTERNOON...ONE OR MORE BANDS OF LIGHT
TO MODERATE SNOW MAY DEVELOP AND MOVE FROM NORTHWEST TO SOUTHEAST
ACROSS NORTHERN AND CENTRAL OKLAHOMA THROUGH SUNDAY NIGHT. LIGHT
SNOW ACCUMULATIONS APPEAR LIKELY...MAINLY OVER NORTHERN AND
WESTERN OKLAHOMA. LOCALIZED AREAS MAY PICK UP AN INCH OR MORE OF
SNOW SUNDAY INTO SUNDAY NIGHT...RESULTING IN SLICK AND HAZARDOUS
ROADS IN SOME AREAS.
HEADING INTO NEXT WEEK...VERY COLD AND DRY AIR WILL REMAIN IN
PLACE...WITH HIGHS GENERALLY IN THE 30S AND LOWS IN THE TEENS AND
20S. THIS WILL MAKE SNOW/ICE MELT FAIRLY SLOW FOR AREAS THAT SEE
MEASURABLE SNOWFALL OVER THE WEEKEND.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 33 19 39 27 / 0 0 0 10
HOBART OK 33 18 39 28 / 0 0 0 20
WICHITA FALLS TX 36 21 43 30 / 0 0 0 10
GAGE OK 27 13 36 24 / 0 0 0 30
PONCA CITY OK 32 16 36 25 / 0 0 0 10
DURANT OK 37 22 41 27 / 0 0 0 0
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1015 PM EST FRI NOV 14 2014
.SYNOPSIS...
THE ANOMALOUS UPPER TROUGH WILL BRIEFLY LIFT OUT OVER THE WEEKEND
AS SURFACE HIGH PRESSURE SLIDES BY JUST TO THE SOUTH OF
PENNSYLVANIA. AN EVEN DEEPER TROUGH WILL FORM OVER THE GREAT
LAKES AND NORTHEAST CONUS EARLY NEXT WEEK. THIS DEEPENING TROUGH
WILL HELP TO FORM A FAST MOVING AREA OF LOW PRESSURE THAT WILL
TRACK FROM THE DEEP SOUTH TO THE SOUTHERN NEW ENGLAND COAST BY
MONDAY EVENING. THIS WEATHER FEATURE WILL BRING A LIKELIHOOD OF A
LIGHT TO MODERATE SNOWFALL MONDAY ACROSS AT LEAST THE NORTHWEST
HALF OF PENNSYLVANIA. MIXED PRECIPITATION AND RAIN ARE MOST
LIKELY OVER THE CENTRAL AND SOUTHEAST ON MONDAY.
&&
.NEAR TERM /UNTIL 7 AM SATURDAY MORNING/...
10 PM UPDATE...
SNOW SHOWERS ARE STILL MAINLY CELLULAR IN ONLY SEMI-CONCENTRATED
BANDS. CELLS MOVING VERY QUICKLY AND CIGS GET HIGH PRETTY QUICKLY
AWAY FROM THE LAKE. EVEN KERI IS HIGH-MVFR WHEN IT DOES SNOW
THERE. THUS...ACCUMS FOR THE OVERNIGHT LOOK ON TRACK. AS
EARLIER...HRRR AND RAP HANDLING THE NEAR-TERM WAGGLE TO THE SOUTH
OF THE BROAD BANDS. THEY AND THE NEWEST NAM CONTINUE TO SINK THE
BANDS SOUTHWARD FOR A FEW MORE HOURS...THEN STALL FOR A FEW HOURS
AND SHOVE THEM BACK TO THE NORTH AS THE CENTER OF THE BIG SFC HIGH
MOVES INTO THE CENTRAL APPALACHIANS.
730 PM UPDATE...
HRRR AND RUC HANDLING THE SHIFT OF THE BANDS TO THE SOUTH WITH
VEERING LOW LEVEL WINDS VERY NICELY. THE NEAR TERM PREDICTIONS
PORTRAY THE CONTINUED VEERING THROUGH MIDNIGHT OR A LITTLE
LATER...THEN A TURN AROUND AND BACKING TO A GENERALLY SWRLY FLOW
IN THE CLOUD LAYER BY SUNRISE. THUS...HAVE HIGH CONFIDENCE IN
KEEPING ALL THE WEATHER ELEMENTS VERY CLOSE TO CURRENT
PROJECTIONS. LES ADVY STILL LOOKING GOOD FOR WARREN CO.
PREV...
A PERSISTENT...COLD NORTHWESTERLY FLOW OVR THE GRT LKS WILL
CONTINUE TO PRODUCE FREQUENT SNOW SHOWERS ACROSS THE NW MTNS
AND LAUREL HIGHLANDS TONIGHT WITH ADDITIONAL LIGHT ACCUMULATIONS
OF A COATING TO ONE INCH ACROSS MANY AREAS NEAR...AND JUST TO THE
WEST OF RT 219.
HIGH RES MODELS SHOW DIRECTIONAL SHEAR IN THE LOWEST FEW KM
BECOMING BETTER ALIGNED LATE THIS AFTERNOON THROUGH MUCH OF
TONIGHT...WHICH WILL CREATE 2 OR 3...MORE ORGANIZED LES BANDS
/THAT WILL PENETRATE FURTHER INLAND THANKS TO A MEAN 20KT FLOW
FROM 300 DEG IN THE LOWEST 2 KM/.
BRIEF PERIODS OF 1/4-1/2SM SNOW WILL OCCUR WITHIN THESE BANDS.
EXTENDED THE LES ADVISORY FOR WARREN COUNTY THROUGH 12Z SATURDAY
AS THE PASSAGE OF A WEAK UPPER SHORT WAVE AND SFC TROUGH WILL LEAD
TO A BETTER UPSTREAM MOISTURE TAP OFF SOUTHERN LAKE HURON.
AREAS OF MORE SHALLOW BKN-OVC STRATO CU ACROSS THE NORTH-CENTRAL
MTNS AND CENTRAL RIDGE AND VALLEY REGION /INCLUDING THE SUSQ
VALLEY/ WILL SUPPORT MAINLY FLURRIES AN PERHAPS A BRIEF 2-3SM VSBY
SNOW SHOWER LATE TODAY AND TONIGHT WITH A FEW LOCATIONS SEEING A
POWDERY DUSTING OF SNOW.
MIN TEMPS EARLY SATURDAY WILL BE IN THE LOWER TO MID 20S...BUT THE
WEST TO NORTHWEST BREEZE WILL DECREASE TO ABOUT 6-8 KTS AFTER 02Z
SAT.
&&
.SHORT TERM /7 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
EXPECT ANY REMAINING LAKE EFFECT SNOW BANDS TO SHIFT QUICKLY NORTH
OR DISSIPATE DURING LATE MORNING/EARLY AFTERNOON HOURS AS SHEAR
WITHIN THE SFC-800 INCREASES...BEFORE THE MEAN WIND IN THIS LAYER
GRADUALLY BACKS TO THE WEST-SOUTHWEST IN THE AFTERNOON.
ACROSS THE CENTRAL AND SERN ZONES...SOME MORNING CLOUDS AND
FLURRIES WILL LIKELY YIELD TO INCREASING AMOUNT OF SUNSHINE
THROUGH THE SHALLOW STRATO CU DECK.
PARTLY TO MOSTLY CLOUDY SKIES IN THE FORM OF MAINLY ALTO CU CLOUDS
EXPECTED FOR SAT NIGHT AS A WARM FRONT LIFTS NE FROM THE OHIO
VALLEY. A BIT OF LIGHT SNOW OR FLURRIES IS POSSIBLE SAT
NIGHT/EARLY SUNDAY ACROSS THE NW HALF OF THE STATE WITH VERY MINOR
ACCUMS AT MOST.
MAX TEMPS SAT WILL BE IN THE L-M 30S ACROSS THE NRN AND WRN
MTNS...AND UPR 30S TO L40S FURTHER SE THROUGH THE SUSQ VALLEY.
LOW TEMPS AT DAYBREAK SUNDAY WILL BE IN THE M-U 20S ACROSS THE
MTNS AND 30-35 ELSEWHERE.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
COLD WEATHER PATTERN CONTINUES THROUGH NEXT WEEK...
ADVISORY LEVEL SNOW ACCUMULATION POSSIBLE ON MONDAY...
UPPER LEVEL RIDGING FROM THE NW COAST TO ALASKA WILL SUSTAIN AND
MAINTAIN A DEEP TROUGH AND UNSEASONABLY COLD AIRMASS OVER THE AREA
THROUGH MUCH OF NEXT WEEK. FORECAST CONFIDENCE REMAINS VERY HIGH
IN A PROLONGED STRETCH OF WELL-BELOW NORMAL TEMPERATURES FOR THIS
TIME OF YEAR WITH THE CORE OF THE COLD IMPACTING THE CWA TUE-WED.
MODELS CONTINUE TO SHOW A LEAD SHORTWAVE CROSSING THE ERN GREAT
LAKES ON SUNDAY...WHICH COULD SPREAD SOME LIGHT SNOW/RAIN INTO THE
WESTERN COUNTIES DURING THE DAY. RELOADING CENTRAL US TROUGH
BECOMES WELL ESTABLISHED BY 12Z MONDAY WITH CORE OF NEGATIVE
HEIGHT ANOMALIES /-3 STD/ SPREADING EWD FROM THE UPPER MIDWEST
THROUGH THE OH VALLEY.
THERE IS AN EMERGING CONSENSUS AMONG THE GLOBAL GUIDANCE IN A
BROAD AREA OF PCPN OVERSPREADING THE AREA ON MONDAY...AS MOISTURE
AND LIFT BECOME ENHANCED WITHIN THE ENTRANCE REGION OF A STRONG
UPPER JET EAST OF THE DEEP TROUGH...ALONG SHARPENING LOW LEVEL
THERMAL GRADIENT/FRONTAL AXIS MARKING LEADING EDGE OF ARCTIC
AIRMASS. FOLLOWED WPC BLEND FOR QPF AND THERMAL PROFILES WHICH
SUPPORTS POTENTIAL FOR ADVISORY LEVEL SNOW ACCUMULATIONS /2-4
INCHES/ OVER THE NW 1/2 OF THE CWA. FURTHER SOUTH/EAST...A RAIN TO
SNOW MIX TO CHANGEOVER SCENARIO SEEMS LKLY WITH LOWER ACCUMS GIVEN
INITIALLY WARM BLYR. ALTHOUGH THE PTYPE DETAILS AND SNOW ACCUMS
ARE STILL UNCERTAIN...CONFIDENCE IN WINTER WEATHER IMPACTS TO THE
MONDAY MORNING COMMUTE IS INCREASING ESPECIALLY OVER THE WRN 1/2
OF THE CWA. WILL ADD WORDING INTO THE HWO.
A FRIGID SURGE OF ARCTIC AIR WILL BLAST INTO THE REGION BEHIND
THIS SYSTEM ON TUESDAY AND PERSIST THRU THE MIDDLE OF NEXT WEEK.
MEAN 85H TEMPS ARND -15C IN BOTH THE GEFS/ECENS TRANSLATE INTO
HIGH TEMPS BELOW FREEZING FOR MOST OF CENTRAL PA TUE/WED. WIND
CHILLS IN THE LOW TEENS AND SINGLE DIGITS ARE LKLY AND MAY EVEN
DIP BELOW 0F OVER THE WRN MTNS. THE TRANSITION BACK TO A COLD
CYCLONIC NW FLOW PATTERN WILL FAVOR LAKE EFFECT AND TERRAIN
ENHANCED SNOW SHOWERS OVER THE NW MTNS WITH COLD AND DRY
CONDITIONS FROM THE CENTRAL RIDGES INTO THE LWR SUSQ VLY.
SOME MODERATION IN TEMPS MAY BE IN SIGHT BY THE END OF NEXT WEEK
AS MODELS AND ENSEMBLES SHOW THE UPSTREAM PATTERN CONFIGURATION
BREAKING DOWN.
&&
.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
LITTLE CHANGE IS EXPECTED ACRS THE REGION TONIGHT AS COLD AIR
RIDING SOUTHEAST ACROSS THE RELATIVELY WARMER WATERS OF THE GREAT
LAKES IS LIFTED OVER THE HIGHER TERRAIN IN WESTERN PA.
THIS SHOULD PRODUCE A LARGE AREA OF MVFR REDUCTIONS WITH SCT IFR
CONDITIONS IN MEANDERING BANDS OF SNOW SHOWERS FROM NEAR KBFD-
KJST TO AOO.
VFR TO HIGH-END MVFR STRATOCU AND SCT LIGHT SNOW SHOWERS/FLURRIES
WILL SPILL INTO CENTRAL MTNS AND SUSQ LATE TODAY AND TONIGHT.
WINDS WILL SETTLE TO 6-8 KTS TONIGHT.
OUTLOOK...
SAT...AM SNOW SHOWERS/REDUCED VSBYS POSS AT KBFD AND JST.
SUN...SNOW SHOWERS/REDUCED VSBYS POSS AT KBFD.
MON...LGT-MDT SNOW/LOW CIGS EXPECTED ACROSS THE NW HALF OF PA.
RAIN/MIXED PRECIP AND LOW CIGS POSS SE.
TUE AND WED...BLUSTERY AND VERY COLD WITH SNOW SHOWERS AND AREAS
OF REDUCED CIGS/VSBYS - MAINLY ACROSS THE NW HALF OF PENN.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
LAKE EFFECT SNOW ADVISORY UNTIL 7 AM EST SATURDAY FOR PAZ004.
&&
$$
SYNOPSIS...DANGELO/LAMBERT
NEAR TERM...DANGELO/LAMBERT
SHORT TERM...LAMBERT
LONG TERM...STEINBUGL
AVIATION...LAMBERT/CERU
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
813 PM EST FRI NOV 14 2014
.SYNOPSIS...
THE ANOMALOUS UPPER TROUGH WILL BRIEFLY LIFT OUT OVER THE WEEKEND
AS SURFACE HIGH PRESSURE SLIDES BY JUST TO THE SOUTH OF
PENNSYLVANIA. AN EVEN DEEPER TROUGH WILL FORM OVER THE GREAT
LAKES AND NORTHEAST CONUS EARLY NEXT WEEK. THIS DEEPENING TROUGH
WILL HELP TO FORM A FAST MOVING AREA OF LOW PRESSURE THAT WILL
TRACK FROM THE DEEP SOUTH TO THE SOUTHERN NEW ENGLAND COAST BY
MONDAY EVENING. THIS WEATHER FEATURE WILL BRING A LIKELIHOOD OF A
LIGHT TO MODERATE SNOWFALL MONDAY ACROSS AT LEAST THE NORTHWEST
HALF OF PENNSYLVANIA. MIXED PRECIPITATION AND RAIN ARE MOST
LIKELY OVER THE CENTRAL AND SOUTHEAST ON MONDAY.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
730 PM UPDATE...
HRRR AND RUC HANDLING THE SHIFT OF THE BANDS TO THE SOUTH WITH
VEERING LOW LEVEL WINDS VERY NICELY. THE NEAR TERM PREDICTIONS
PORTRAY THE CONTINUED VEERING THROUGH MIDNIGHT OR A LITTLE
LATER...THEN A TURN AROUND AND BACKING TO A GENERALLY SWRLY FLOW
IN THE CLOUD LAYER BY SUNRISE. THUS...HAVE HIGH CONFIDENCE IN
KEEPING ALL THE WEATHER ELEMENTS VERY CLOSE TO CURRENT
PROJECTIONS. LES ADVY STILL LOOKING GOOD FOR WARREN CO.
PREV...
A PERSISTENT...COLD NORTHWESTERLY FLOW OVR THE GRT LKS WILL
CONTINUE TO PRODUCE FREQUENT SNOW SHOWERS ACROSS THE NW MTNS
AND LAUREL HIGHLANDS TONIGHT WITH ADDITIONAL LIGHT ACCUMULATIONS
OF A COATING TO ONE INCH ACROSS MANY AREAS NEAR...AND JUST TO THE
WEST OF RT 219.
HIGH RES MODELS SHOW DIRECTIONAL SHEAR IN THE LOWEST FEW KM
BECOMING BETTER ALIGNED LATE THIS AFTERNOON THROUGH MUCH OF
TONIGHT...WHICH WILL CREATE 2 OR 3...MORE ORGANIZED LES BANDS
/THAT WILL PENETRATE FURTHER INLAND THANKS TO A MEAN 20KT FLOW
FROM 300 DEG IN THE LOWEST 2 KM/.
BRIEF PERIODS OF 1/4-1/2SM SNOW WILL OCCUR WITHIN THESE BANDS.
EXTENDED THE LES ADVISORY FOR WARREN COUNTY THROUGH 12Z SATURDAY
AS THE PASSAGE OF A WEAK UPPER SHORT WAVE AND SFC TROUGH WILL LEAD
TO A BETTER UPSTREAM MOISTURE TAP OFF SOUTHERN LAKE HURON.
AREAS OF MORE SHALLOW BKN-OVC STRATO CU ACROSS THE NORTH-CENTRAL
MTNS AND CENTRAL RIDGE AND VALLEY REGION /INCLUDING THE SUSQ
VALLEY/ WILL SUPPORT MAINLY FLURRIES AN PERHAPS A BRIEF 2-3SM VSBY
SNOW SHOWER LATE TODAY AND TONIGHT WITH A FEW LOCATIONS SEEING A
POWDERY DUSTING OF SNOW.
MIN TEMPS EARLY SATURDAY WILL BE IN THE LOWER TO MID 20S...BUT THE
WEST TO NORTHWEST BREEZE WILL DECREASE TO ABOUT 6-8 KTS AFTER 02Z
SAT.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
EXPECT ANY REMAINING LAKE EFFECT SNOW BANDS TO SHIFT QUICKLY NORTH
OR DISSIPATE DURING LATE MORNING/EARLY AFTERNOON HOURS AS SHEAR
WITHIN THE SFC-800 INCREASES...BEFORE THE MEAN WIND IN THIS LAYER
GRADUALLY BACKS TO THE WEST-SOUTHWEST IN THE AFTERNOON.
ACROSS THE CENTRAL AND SERN ZONES...SOME MORNING CLOUDS AND
FLURRIES WILL LIKELY YIELD TO INCREASING AMOUNT OF SUNSHINE
THROUGH THE SHALLOW STRATO CU DECK.
PARTLY TO MOSTLY CLOUDY SKIES IN THE FORM OF MAINLY ALTO CU CLOUDS
EXPECTED FOR SAT NIGHT AS A WARM FRONT LIFTS NE FROM THE OHIO
VALLEY. A BIT OF LIGHT SNOW OR FLURRIES IS POSSIBLE SAT
NIGHT/EARLY SUNDAY ACROSS THE NW HALF OF THE STATE WITH VERY MINOR
ACCUMS AT MOST.
MAX TEMPS SAT WILL BE IN THE L-M 30S ACROSS THE NRN AND WRN
MTNS...AND UPR 30S TO L40S FURTHER SE THROUGH THE SUSQ VALLEY.
LOW TEMPS AT DAYBREAK SUNDAY WILL BE IN THE M-U 20S ACROSS THE
MTNS AND 30-35 ELSEWHERE.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
COLD WEATHER PATTERN CONTINUES THROUGH NEXT WEEK...
ADVISORY LEVEL SNOW ACCUMULATION POSSIBLE ON MONDAY...
UPPER LEVEL RIDGING FROM THE NW COAST TO ALASKA WILL SUSTAIN AND
MAINTAIN A DEEP TROUGH AND UNSEASONABLY COLD AIRMASS OVER THE AREA
THROUGH MUCH OF NEXT WEEK. FORECAST CONFIDENCE REMAINS VERY HIGH
IN A PROLONGED STRETCH OF WELL-BELOW NORMAL TEMPERATURES FOR THIS
TIME OF YEAR WITH THE CORE OF THE COLD IMPACTING THE CWA TUE-WED.
MODELS CONTINUE TO SHOW A LEAD SHORTWAVE CROSSING THE ERN GREAT
LAKES ON SUNDAY...WHICH COULD SPREAD SOME LIGHT SNOW/RAIN INTO THE
WESTERN COUNTIES DURING THE DAY. RELOADING CENTRAL US TROUGH
BECOMES WELL ESTABLISHED BY 12Z MONDAY WITH CORE OF NEGATIVE
HEIGHT ANOMALIES /-3 STD/ SPREADING EWD FROM THE UPPER MIDWEST
THROUGH THE OH VALLEY.
THERE IS AN EMERGING CONSENSUS AMONG THE GLOBAL GUIDANCE IN A
BROAD AREA OF PCPN OVERSPREADING THE AREA ON MONDAY...AS MOISTURE
AND LIFT BECOME ENHANCED WITHIN THE ENTRANCE REGION OF A STRONG
UPPER JET EAST OF THE DEEP TROUGH...ALONG SHARPENING LOW LEVEL
THERMAL GRADIENT/FRONTAL AXIS MARKING LEADING EDGE OF ARCTIC
AIRMASS. FOLLOWED WPC BLEND FOR QPF AND THERMAL PROFILES WHICH
SUPPORTS POTENTIAL FOR ADVISORY LEVEL SNOW ACCUMULATIONS /2-4
INCHES/ OVER THE NW 1/2 OF THE CWA. FURTHER SOUTH/EAST...A RAIN TO
SNOW MIX TO CHANGEOVER SCENARIO SEEMS LKLY WITH LOWER ACCUMS GIVEN
INITIALLY WARM BLYR. ALTHOUGH THE PTYPE DETAILS AND SNOW ACCUMS
ARE STILL UNCERTAIN...CONFIDENCE IN WINTER WEATHER IMPACTS TO THE
MONDAY MORNING COMMUTE IS INCREASING ESPECIALLY OVER THE WRN 1/2
OF THE CWA. WILL ADD WORDING INTO THE HWO.
A FRIGID SURGE OF ARCTIC AIR WILL BLAST INTO THE REGION BEHIND
THIS SYSTEM ON TUESDAY AND PERSIST THRU THE MIDDLE OF NEXT WEEK.
MEAN 85H TEMPS ARND -15C IN BOTH THE GEFS/ECENS TRANSLATE INTO
HIGH TEMPS BELOW FREEZING FOR MOST OF CENTRAL PA TUE/WED. WIND
CHILLS IN THE LOW TEENS AND SINGLE DIGITS ARE LKLY AND MAY EVEN
DIP BELOW 0F OVER THE WRN MTNS. THE TRANSITION BACK TO A COLD
CYCLONIC NW FLOW PATTERN WILL FAVOR LAKE EFFECT AND TERRAIN
ENHANCED SNOW SHOWERS OVER THE NW MTNS WITH COLD AND DRY
CONDITIONS FROM THE CENTRAL RIDGES INTO THE LWR SUSQ VLY.
SOME MODERATION IN TEMPS MAY BE IN SIGHT BY THE END OF NEXT WEEK
AS MODELS AND ENSEMBLES SHOW THE UPSTREAM PATTERN CONFIGURATION
BREAKING DOWN.
&&
.AVIATION /01Z SATURDAY THROUGH WEDNESDAY/...
LITTLE CHANGE IS EXPECTED ACRS THE REGION TONIGHT AS COLD AIR
RIDING SOUTHEAST ACROSS THE RELATIVELY WARMER WATERS OF THE GREAT
LAKES IS LIFTED OVER THE HIGHER TERRAIN IN WESTERN PA.
THIS SHOULD PRODUCE A LARGE AREA OF MVFR REDUCTIONS WITH SCT IFR
CONDITIONS IN MEANDERING BANDS OF SNOW SHOWERS FROM NEAR KBFD-
KJST TO AOO.
VFR TO HIGH-END MVFR STRATOCU AND SCT LIGHT SNOW SHOWERS/FLURRIES
WILL SPILL INTO CENTRAL MTNS AND SUSQ LATE TODAY AND TONIGHT.
WINDS WILL SETTLE TO 6-8 KTS TONIGHT.
OUTLOOK...
SAT...AM SNOW SHOWERS/REDUCED VSBYS POSS AT KBFD AND JST.
SUN...SNOW SHOWERS/REDUCED VSBYS POSS AT KBFD.
MON...LGT-MDT SNOW/LOW CIGS EXPECTED ACROSS THE NW HALF OF PA.
RAIN/MIXED PRECIP AND LOW CIGS POSS SE.
TUE AND WED...BLUSTERY AND VERY COLD WITH SNOW SHOWERS AND AREAS
OF REDUCED CIGS/VSBYS - MAINLY ACROSS THE NW HALF OF PENN.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
LAKE EFFECT SNOW ADVISORY UNTIL 7 AM EST SATURDAY FOR PAZ004.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...DANGELO/LAMBERT
SHORT TERM...LAMBERT
LONG TERM...STEINBUGL
AVIATION...LAMBERT/CERU
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
736 PM EST FRI NOV 14 2014
.SYNOPSIS...
THE ANOMALOUS UPPER TROUGH WILL BRIEFLY LIFT OUT OVER THE WEEKEND
AS SURFACE HIGH PRESSURE SLIDES BY JUST TO THE SOUTH OF
PENNSYLVANIA. AN EVEN DEEPER TROUGH WILL FORM OVER THE GREAT
LAKES AND NORTHEAST CONUS EARLY NEXT WEEK. THIS DEEPENING TROUGH
WILL HELP TO FORM A FAST MOVING AREA OF LOW PRESSURE THAT WILL
TRACK FROM THE DEEP SOUTH TO THE SOUTHERN NEW ENGLAND COAST BY
MONDAY EVENING. THIS WEATHER FEATURE WILL BRING A LIKELIHOOD OF A
LIGHT TO MODERATE SNOWFALL MONDAY ACROSS AT LEAST THE NORTHWEST
HALF OF PENNSYLVANIA. MIXED PRECIPITATION AND RAIN ARE MOST
LIKELY OVER THE CENTRAL AND SOUTHEAST ON MONDAY.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
730 PM UPDATE...
HRRR AND RUC HANDLING THE SHIFT OF THE BANDS TO THE SOUTH WITH
VEERING LOW LEVEL WINDS VERY NICELY. THE NEAR TERM PREDICTIONS
PORTRAY THE CONTINUED VEERING THROUGH MIDNIGHT OR A LITTLE
LATER...THEN A TURN AROUND AND BACKING TO A GENERALLY SWRLY FLOW
IN THE CLOUD LAYER BY SUNRISE. THUS...HAVE HIGH CONFIDENCE IN
KEEPING ALL THE WEATHER ELEMENTS VERY CLOSE TO CURRENT
PROJECTIONS. LES ADVY STILL LOOKING GOOD FOR WARREN CO.
PREV...
A PERSISTENT...COLD NORTHWESTERLY FLOW OVR THE GRT LKS WILL
CONTINUE TO PRODUCE FREQUENT SNOW SHOWERS ACROSS THE NW MTNS
AND LAUREL HIGHLANDS TONIGHT WITH ADDITIONAL LIGHT ACCUMULATIONS
OF A COATING TO ONE INCH ACROSS MANY AREAS NEAR...AND JUST TO THE
WEST OF RT 219.
HIGH RES MODELS SHOW DIRECTIONAL SHEAR IN THE LOWEST FEW KM
BECOMING BETTER ALIGNED LATE THIS AFTERNOON THROUGH MUCH OF
TONIGHT...WHICH WILL CREATE 2 OR 3...MORE ORGANIZED LES BANDS
/THAT WILL PENETRATE FURTHER INLAND THANKS TO A MEAN 20KT FLOW
FROM 300 DEG IN THE LOWEST 2 KM/.
BRIEF PERIODS OF 1/4-1/2SM SNOW WILL OCCUR WITHIN THESE BANDS.
EXTENDED THE LES ADVISORY FOR WARREN COUNTY THROUGH 12Z SATURDAY
AS THE PASSAGE OF A WEAK UPPER SHORT WAVE AND SFC TROUGH WILL LEAD
TO A BETTER UPSTREAM MOISTURE TAP OFF SOUTHERN LAKE HURON.
AREAS OF MORE SHALLOW BKN-OVC STRATO CU ACROSS THE NORTH-CENTRAL
MTNS AND CENTRAL RIDGE AND VALLEY REGION /INCLUDING THE SUSQ
VALLEY/ WILL SUPPORT MAINLY FLURRIES AN PERHAPS A BRIEF 2-3SM VSBY
SNOW SHOWER LATE TODAY AND TONIGHT WITH A FEW LOCATIONS SEEING A
POWDERY DUSTING OF SNOW.
MIN TEMPS EARLY SATURDAY WILL BE IN THE LOWER TO MID 20S...BUT THE
WEST TO NORTHWEST BREEZE WILL DECREASE TO ABOUT 6-8 KTS AFTER 02Z
SAT.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
EXPECT ANY REMAINING LAKE EFFECT SNOW BANDS TO SHIFT QUICKLY NORTH
OR DISSIPATE DURING LATE MORNING/EARLY AFTERNOON HOURS AS SHEAR
WITHIN THE SFC-800 INCREASES...BEFORE THE MEAN WIND IN THIS LAYER
GRADUALLY BACKS TO THE WEST-SOUTHWEST IN THE AFTERNOON.
ACROSS THE CENTRAL AND SERN ZONES...SOME MORNING CLOUDS AND
FLURRIES WILL LIKELY YIELD TO INCREASING AMOUNT OF SUNSHINE
THROUGH THE SHALLOW STRATO CU DECK.
PARTLY TO MOSTLY CLOUDY SKIES IN THE FORM OF MAINLY ALTO CU CLOUDS
EXPECTED FOR SAT NIGHT AS A WARM FRONT LIFTS NE FROM THE OHIO
VALLEY. A BIT OF LIGHT SNOW OR FLURRIES IS POSSIBLE SAT
NIGHT/EARLY SUNDAY ACROSS THE NW HALF OF THE STATE WITH VERY MINOR
ACCUMS AT MOST.
MAX TEMPS SAT WILL BE IN THE L-M 30S ACROSS THE NRN AND WRN
MTNS...AND UPR 30S TO L40S FURTHER SE THROUGH THE SUSQ VALLEY.
LOW TEMPS AT DAYBREAK SUNDAY WILL BE IN THE M-U 20S ACROSS THE
MTNS AND 30-35 ELSEWHERE.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
COLD WEATHER PATTERN CONTINUES THROUGH NEXT WEEK...
ADVISORY LEVEL SNOW ACCUMULATION POSSIBLE ON MONDAY...
UPPER LEVEL RIDGING FROM THE NW COAST TO ALASKA WILL SUSTAIN AND
MAINTAIN A DEEP TROUGH AND UNSEASONABLY COLD AIRMASS OVER THE AREA
THROUGH MUCH OF NEXT WEEK. FORECAST CONFIDENCE REMAINS VERY HIGH
IN A PROLONGED STRETCH OF WELL-BELOW NORMAL TEMPERATURES FOR THIS
TIME OF YEAR WITH THE CORE OF THE COLD IMPACTING THE CWA TUE-WED.
MODELS CONTINUE TO SHOW A LEAD SHORTWAVE CROSSING THE ERN GREAT
LAKES ON SUNDAY...WHICH COULD SPREAD SOME LIGHT SNOW/RAIN INTO THE
WESTERN COUNTIES DURING THE DAY. RELOADING CENTRAL US TROUGH
BECOMES WELL ESTABLISHED BY 12Z MONDAY WITH CORE OF NEGATIVE
HEIGHT ANOMALIES /-3 STD/ SPREADING EWD FROM THE UPPER MIDWEST
THROUGH THE OH VALLEY.
THERE IS AN EMERGING CONSENSUS AMONG THE GLOBAL GUIDANCE IN A
BROAD AREA OF PCPN OVERSPREADING THE AREA ON MONDAY...AS MOISTURE
AND LIFT BECOME ENHANCED WITHIN THE ENTRANCE REGION OF A STRONG
UPPER JET EAST OF THE DEEP TROUGH...ALONG SHARPENING LOW LEVEL
THERMAL GRADIENT/FRONTAL AXIS MARKING LEADING EDGE OF ARCTIC
AIRMASS. FOLLOWED WPC BLEND FOR QPF AND THERMAL PROFILES WHICH
SUPPORTS POTENTIAL FOR ADVISORY LEVEL SNOW ACCUMULATIONS /2-4
INCHES/ OVER THE NW 1/2 OF THE CWA. FURTHER SOUTH/EAST...A RAIN TO
SNOW MIX TO CHANGEOVER SCENARIO SEEMS LKLY WITH LOWER ACCUMS GIVEN
INITIALLY WARM BLYR. ALTHOUGH THE PTYPE DETAILS AND SNOW ACCUMS
ARE STILL UNCERTAIN...CONFIDENCE IN WINTER WEATHER IMPACTS TO THE
MONDAY MORNING COMMUTE IS INCREASING ESPECIALLY OVER THE WRN 1/2
OF THE CWA. WILL ADD WORDING INTO THE HWO.
A FRIGID SURGE OF ARCTIC AIR WILL BLAST INTO THE REGION BEHIND
THIS SYSTEM ON TUESDAY AND PERSIST THRU THE MIDDLE OF NEXT WEEK.
MEAN 85H TEMPS ARND -15C IN BOTH THE GEFS/ECENS TRANSLATE INTO
HIGH TEMPS BELOW FREEZING FOR MOST OF CENTRAL PA TUE/WED. WIND
CHILLS IN THE LOW TEENS AND SINGLE DIGITS ARE LKLY AND MAY EVEN
DIP BELOW 0F OVER THE WRN MTNS. THE TRANSITION BACK TO A COLD
CYCLONIC NW FLOW PATTERN WILL FAVOR LAKE EFFECT AND TERRAIN
ENHANCED SNOW SHOWERS OVER THE NW MTNS WITH COLD AND DRY
CONDITIONS FROM THE CENTRAL RIDGES INTO THE LWR SUSQ VLY.
SOME MODERATION IN TEMPS MAY BE IN SIGHT BY THE END OF NEXT WEEK
AS MODELS AND ENSEMBLES SHOW THE UPSTREAM PATTERN CONFIGURATION
BREAKING DOWN.
&&
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
LITTLE CHANGE IS EXPECTED ACRS THE REGION LATE TODAY AND TONIGHT
AS COLD AIR RIDING SOUTHEAST ACROSS THE RELATIVELY WARMER WATERS
OF THE GREAT LAKES IS LIFTED OVER THE HIGHER TERRAIN IN WESTERN
PA...PRODUCING A LARGE AREA OF MVFR REDUCTIONS WITH SCT IFR
CONDITIONS IN MEANDERING BANDS OF SNOW SHOWERS FROM NEAR
KBFD-KJST.
VFR TO HIGH-END MVFR STRATOCU AND SCT LIGHT SNOW SHOWERS/FLURRIES
WILL SPILL INTO CENTRAL MTNS AND SUSQ LATE TODAY AND TONIGHT.
WINDS WILL BE IN THE 10-15 KT RANGE WITH GUSTS UP TO AROUND 20 KTS
AT A FEW LOCATIONS THROUGH 23Z. WINDS WILL SETTLE TO 6-8 KTS
TONIGHT.
OUTLOOK...
SAT...AM SNOW SHOWERS/REDUCED VSBYS POSS AT KBFD AND JST.
SUN...SNOW SHOWERS/REDUCED VSBYS POSS AT KBFD.
MON...LGT-MDT SNOW/LOW CIGS EXPECTED ACROSS THE NW HALF OF PA.
RAIN/MIXED PRECIP AND LOW CIGS POSS SE.
TUE AND WED...BLUSTERY AND VERY COLD WITH SNOW SHOWERS AND AREAS
OF REDUCED CIGS/VSBYS - MAINLY ACROSS THE NW HALF OF PENN.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
LAKE EFFECT SNOW ADVISORY UNTIL 7 AM EST SATURDAY FOR PAZ004.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...DANGELO/LAMBERT
SHORT TERM...LAMBERT
LONG TERM...STEINBUGL
AVIATION...LAMBERT
AREA FORECAST DISCUSSION
NWS MORRISTOWN TN
1047 AM EST THU NOV 13 2014
.DISCUSSION...
BAND OF SNOW NOW OVER THE NORTHWESTERN PARTS OF THE CWA...BUT
LOOKING LIKE THIS WILL NOT PENETRATE TOO FAR INTO OUR AREA...PER
LAST FEW HRRR RUNS. WILL LEAVE SOME LIGHT POPS IN THE NORTHEASTERN
SECTIONS FOR THIS AFTERNOON AS SOME LIGHT INSTABILITY WILL BE
PUSHING INTO THAT AREA DURING THE AFTERNOON. WILL HAVE AT LEAST THE
MENTION OF SPRINKLES FOLLOWED BY FLURRIES OVER THE NORTHERN HALF OF
THE AREA. DRIER AIR WILL BE PUSHING INTO THE AREA AND SHOULD END
ANY REMAINING DRIZZLE. TEMPERATURE FORECAST IS ON TRACK.
&&
.PRELIMINARY POINT TEMPS/POPS...
CHATTANOOGA AIRPORT, TN 44 25 42 25 / 10 0 10 10
KNOXVILLE MCGHEE TYSON AIRPORT, TN 42 23 39 23 / 10 10 10 10
OAK RIDGE, TN 42 23 38 23 / 10 10 10 10
TRI CITIES AIRPORT, TN 44 24 34 19 / 20 10 10 10
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
GM
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
1112 PM CST WED NOV 12 2014
.AVIATION...
VFR CONDITIONS WILL PREVAIL WITH BREEZY NORTHERLY WINDS CONTINUING
THROUGH TOMORROW AFTERNOON. SPEEDS WILL FINALLY DECREASE TOMORROW
EVENING AS SKIES BECOME MOSTLY CLEAR. VERY SMALL CHANCE FOR A
PASSING SHOWER TONIGHT...PROBABILITIES ARE TOO LOW TO MENTION IN
THE TAFS.
HAMPSHIRE
&&
.PREV DISCUSSION... /ISSUED 959 PM CST WED NOV 12 2014/
UPDATE...
RADAR ECHOES CONTINUE ACROSS OUR AREA WITH CURRENT TEMPS IN THE
MID 30S ACROSS THE HILL COUNTRY. THIS ACTIVITY IS EXPECTED TO
CONTINUE FOR THE NEXT SEVERAL HOURS AS THE LATEST HRRR HIRES
SOLUTION MODEL SUGGEST. THEREFORE...WILL GO WITH A SLIGHT CHANCE
FOR COLD/FREEZING RAIN LATE TONIGHT AS TEMPS REACH THE 32 DEGREE
MARK. NO ACCUMULATION EXPECTED. UPDATED ZONES OUT SHORTLY.
PREV DISCUSSION... /ISSUED 755 PM CST WED NOV 12 2014/
UPDATE...
AN UPPER LEVEL DISTURBANCE MOVING NORTHEASTWARD ACROSS THE RIO GRANDE
IS HELPING FOR LIGHT RAIN TO FORM OVER THE SOUTHERN COUNTIES.
LATEST HRRR SHOWS LIGHT RAIN OVER THAT AREA TO ABOUT MIDNIGHT
BEFORE SHIFTING TO THE EAST AND AWAY OF THE REGION. WILL ADD A SLIGHT
CHANCE FOR LIGHT RAIN MAINLY ALONG AND EAST OF PEARSALL TO SEGUIN
TO SCHULENBURG LINE TO MIDNIGHT TONIGHT. UPDATED ZONES OUT SHORTLY.
PREV DISCUSSION... /ISSUED 504 PM CST WED NOV 12 2014/
AVIATION...
VFR CLOUD DECK REMAINS IN PLACE ACROSS ALL TAF SITES AND THIS WILL
CONTINUE FOR THE NEXT 20-24 HOURS BEFORE SKIES FINALLY BEGIN TO
CLEAR. CIGS WILL LOWER OVERNIGHT FOR THE I-35 TAF SITES TO AROUND
5KFT AS A WEAK MID-LEVEL DISTURBANCE MOVES INTO THE AREA FROM THE
WEST. THE LOW-LEVELS OF THE ATMOSPHERE WILL BE MUCH TOO DRY FOR
ANY PRECIP. OTHERWISE...BREEZY NORTHERLY FLOW SHOULD CONTINUE
THROUGH THE PERIOD.
HAMPSHIRE
PREV DISCUSSION... /ISSUED 341 PM CST WED NOV 12 2014/
SHORT TERM (TONIGHT THROUGH THURSDAY NIGHT)...
WEAK ISENTROPIC LIFT AHEAD OF AN APPROACHING SHORTWAVE HAS ALLOWED
A LOW CLOUD DECK TO MOVE BACK OVER MUCH OF SOUTH CENTRAL TEXAS
TODAY. EARLIER NAM AND HI-RES MODEL RUNS HAD INDICATED SOME
PRECIPITATION FOR TONIGHT. HOWEVER...LATEST RUNS NO LONGER SHOW
IT. THIS IS REASONABLE AS MOISTURE DEPTH IS SHALLOW AND SUFFICIENT
FOR ONLY CLOUD FORMATION AND MAINTENANCE. EVEN THOUGH CLOUDS
PERSIST OVERNIGHT INTO THURSDAY MORNING...COLD ADVECTION CONTINUES
AND ALLOWS FOR SLIGHTLY MORE WIDESPREAD FREEZING TEMPERATURES FOR
TONIGHT INTO THURSDAY MORNING ACROSS THE HILL COUNTRY AND AREAS
ALONG THE ESCARPMENT WEST OF I-35. MANY AREAS OF THE HILL COUNTRY
THAT STAYED ABOVE FREEZING LAST NIGHT INTO THIS MORNING WILL FALL
BELOW FREEZING BY THURSDAY MORNING. THE FEW SPOTS THAT STAYED
ABOVE FREEZING IN GILLESPIE AND KERR COUNTIES WILL FALL BELOW
FREEZING BY THURSDAY MORNING. AREAS ALONG THE ESCARPMENT WEST OF
I-35 IN HAYS...TRAVIS AND WILLIAMSON COUNTIES WILL HAVE FREEZING
TEMPERATURES FOR 2 TO 3 HOURS AROUND SUNRISE THURSDAY. HOWEVER...
THE AUSTIN METRO AREA WILL REMAIN JUST ABOVE FREEZING. ISENTROPIC
LIFT WANES ON THURSDAY AS THE SHORTWAVE MOVES EAST OF TEXAS
RESULTING IN DECREASING CLOUDS. TEMPERATURES WILL WARM ONLY ABOUT
10 DEGREES OR SO DURING THE DAY DUE CLOUDS LINGERING IN THE
MORNING AND CONTINUED COLD ADVECTION. SKIES BECOME CLEAR TO PARTLY
CLOUDY AND COMBINED WITH DECREASING WINDS WILL ALLOW FOR A
WIDESPREAD FREEZE ACROSS SOUTH CENTRAL TEXAS THURSDAY NIGHT INTO
FRIDAY MORNING. A FREEZE WARNING WILL LIKELY BE ISSUED FOR THE
REMAINDER OF SOUTH CENTRAL TEXAS FOR THURSDAY NIGHT INTO FRIDAY
MORNING IN LATER FORECASTS.
LONG TERM (FRIDAY THROUGH WEDNESDAY)...
AN UPPER LEVEL TROUGH MOVES ACROSS TEXAS SATURDAY WHILE A SURFACE
TROUGH MOVES TO THE NORTHEAST ACROSS THE TEXAS COASTAL WATERS.
ISENTROPIC LIFT DEVELOPS FRIDAY NIGHT LEADING TO SLIGHT CHANCE TO
CHANCE OF RAIN SATURDAY INTO SATURDAY NIGHT EAST OF HIGHWAY 281
AND I-35. A WARM ADVECTION PATTERN WILL KEEP TEMPERATURES ABOVE
FREEZING FRIDAY NIGHT INTO SATURDAY NIGHT. A COLD FRONT MOVES
ACROSS TEXAS SUNDAY WHILE ANOTHER UPPER LEVEL TROUGH MOVES ACROSS
THE SOUTHERN PLAINS BY EARLY MONDAY. ISENTROPIC LIFT BECOMES MORE
WIDESPREAD WITH SLIGHT CHANCES OF RAIN SPREADING TO ALL OF SOUTH
CENTRAL TEXAS SUNDAY NIGHT. THE TROUGH MOVES OFF TO THE EAST
ENDING RAIN CHANCES LATE SUNDAY NIGHT BEFORE SOME FREEZING
TEMPERATURES OCCUR EARLY MONDAY MORNING. MORE WIDESPREAD FREEZING
TEMPERATURES ARE EXPECTED MONDAY NIGHT INTO TUESDAY MORNING. FLOW
OFF THE GULF RETURNS WITH WARMER TEMPERATURES BY NEXT WEDNESDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 34 44 30 48 37 / 10 - - - 10
AUSTIN BERGSTROM INTL AIRPORT 33 45 27 49 35 / 10 - - - 10
NEW BRAUNFELS MUNI AIRPORT 33 46 29 51 37 / 10 - - - 10
BURNET MUNI AIRPORT 30 41 27 48 34 / 10 - - - -
DEL RIO INTL AIRPORT 34 47 31 52 38 / 20 - - - -
GEORGETOWN MUNI AIRPORT 31 42 27 48 35 / 10 - - - -
HONDO MUNI AIRPORT 33 47 27 50 35 / 10 - - - -
SAN MARCOS MUNI AIRPORT 33 45 29 49 36 / 10 - - - 10
LA GRANGE - FAYETTE REGIONAL 34 45 30 50 38 / 10 10 - - 10
SAN ANTONIO INTL AIRPORT 35 47 30 51 39 / 10 - - - 10
STINSON MUNI AIRPORT 36 48 31 51 39 / 20 - - - 10
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
FREEZE WARNING UNTIL 10 AM CST THURSDAY FOR THE FOLLOWING COUNTIES:
BANDERA...BLANCO...BURNET...EDWARDS...GILLESPIE...HAYS...KENDALL...
KERR...LLANO...REAL...TRAVIS...VAL VERDE...WILLIAMSON.
&&
$$
MESOSCALE/AVIATION...29
SYNOPTIC/GRIDS...17
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
254 PM EST THU NOV 13 2014
.SYNOPSIS...
A WEAK DISTURBANCE WILL CROSS THE REGION TONIGHT AND DEEPEN OFF
THE NEW ENGLAND COAST ON FRIDAY. ARCTIC HIGH PRESSURE WILL BUILD
INTO THE REGION INTO AND THROUGH SATURDAY. OUR NEXT POTENTIAL
WEATHER MAKER MOVES ACROSS THE AREA SUNDAY THROUGH MONDAY WITH
GUSTY WINDS AND COLD TEMPERATURES BEHIND IT ON TUESDAY.
&&
.NEAR TERM /THROUGH FRIDAY/...
AS OF 245 PM EST THURSDAY...
THROUGH THIS EVENING...OUR FOCUS WILL BE A REGION OF INSENTROPIC
LIFT THAT WILL HAVE THE CENTER OF ITS FORCING SHIFT EASTWARD ACROSS
THE REGION. CURRENTLY PRECIPITATION ASSOCIATED WITH IT IS EXTENDING
FROM WESTERN MARYLAND SOUTHWEST INTO EASTERN KENTUCKY AND TENNESSEE.
FROM ROUGHLY LONESOME PINE VIRGINIA AND POINTS NORTH...THE
PRECIPITATION WAS IN THE FORM OF VERY LIGHT SNOW. POINTS SOUTH INTO
EASTERN TENNESSEE HAD LIGHT RAIN. REGIONAL RADAR TRENDS AND OUTPUT
FROM THE MESOSCALE HRRR AND RNK WRF-ARW MODELS SUGGEST THE FOLLOWING
PROGRESSION WITHIN THE PRECIPITATION THIS EVENING. THE PRECIPITATION
SLOWLY CONTINUES ITS PROGRESSION INTO THE WESTERN PORTION OF THE
FORECAST AREA THROUGH ROUGHLY 600 PM. AFTER 7 OR 8 PM...THE FOCUS
SHIFTS TO NEAR THE CREST OF THE BLUE RIDGE FROM ROUGHLY ROANOKE VA
AND POINTS NORTH...AND THEN FARTHER EASTWARD TOWARDS BUCKINGHAM BY
1 OR 2 AM.
THE PRECIPITATION TYPE WILL BE MAINLY LIGHT RAIN OR LIGHT SNOW WITH
A TRANSITION FROM WEST TO EAST AS THE EVENING PROGRESSES. MOST AREAS
WILL RECEIVE NO MEASURABLE PRECIPITATION. ELEVATED SURFACES IN THE
WEST AND NORTH MAY BE ABLE TO GET A LIGHT COATING OF SNOW. WHILE NOT
EXPECTED AT ALL LOCATIONS...THERE IS A POTENTIAL FOR A BRIEF PERIOD
OF SLEET DURING THE TRANSITION FROM LIGHT RAIN TO LIGHT SNOW.
AS OUR ENERGY FROM THIS EVENING SHIFTS TO THE COAST...IT WILL TEAM
UP WITH ANOTHER SYSTEM THAT HAS BEEN HUGGING THE COAST DURING THE
COURSE OF TODAY. THIS MERGER AND DEEPENING WILL HELP STRENGTHEN THE
PRESSURE GRADIENT ACROSS THE AREA...AND THUS THE MAGNITUDE OF THE
NORTHWEST FLOW COLD AIR ADVECTION. IT WILL BE THIS TIME WHERE OUR
REALLY GOOD SURGE OF COLDER AIR COMMENCES ACROSS THE REGION. LOWS
TONIGHT WILL RANGE FROM THE UPPER TEENS TO LOWER 20S ACROSS THE
MOUNTAINS WITH UPPER 20S TO LOWER 30S ACROSS THE PIEDMONT.
ON FRIDAY...NORTHWEST FLOW WILL CONTINUE AND HELP MAINTAIN UPSLOPE
CLOUDS ACROSS THE MOUNTAINS THROUGH AT LEAST MIDDAY. IN THE
EAST...THE CLOUD COVER WILL CLEAR EARLY GIVEN A DECENT DOWNSLOPE
COMPONENT. DRIER AIR WILL EVENTUALLY WIN OUT IN THE MOUNTAINS
TOO...WITH MOST REGIONS AT LEAST MOSTLY SUNNY BY THE LATE AFTERNOON.
HIGH TEMPERATURES WILL RANGE FROM THE LOW TO MID 30S ACROSS THE
MOUNTAINS WITH READINGS AROUND 40 TO THE LOWER 40S ACROSS THE
PIEDMONT. SOME OF THE FORECAST HIGHS...ESPECIALLY THOSE IN THE
WEST...ARE ONLY EXPECTED TO BE A COUPLE OF DEGREES ABOVE THE RECORD
LOW MAXIMUMS FOR THE DAY. SPECIFIC LOW MAXIMUM RECORDS FOR FRIDAY
AND SATURDAY ARE IN THE CLIMATE SECTION OF THIS DISCUSSION.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY NIGHT/...
AS OF 205 PM EST THURSDAY...
COLD HIGH PRESSURE WILL SLIDE EAST ACROSS THE AREA FRIDAY NIGHT AND
BE ABOUT OVERHEAD BY SATURDAY MORNING. THIS WILL BRING CLEAR SKIES
UNDER STRONG SUBSIDENCE ALONG WITH VERY COLD EARLY MORNING TEMPS
SATURDAY AS THE CORE OF THE COLDEST 85H SETTLES OVERHEAD. THIS ALONG
WITH GREAT RADIATIONAL COOLING SUPPORTS LOWS IN THE TEENS WEST TO
LOW/MID 20S EAST. RIDGING SHIFTS SLOWLY EAST DURING SATURDAY BUT
SHOULD HANG ON LONG ENOUGH TO KEEP THINGS MOSTLY SUNNY BUT STILL ON
THE COLD SIDE WITH ONLY ABOUT A 3-5+ DEGREE RISE IN 85H TEMPS.
HOWEVER EVEN WITH SOME SLIGHT WARMING ALOFT INFLUX OF HIGH LEVEL
CLOUDS MAY HOLD TEMPS SLIGHTLY BELOW MOS...MAINLY 38-45.
MID LEVEL RIDGING STARTS TO BREAK DOWN SATURDAY NIGHT INTO SUNDAY AS
A DEVELOPING 5H TROUGH STARTS TO APPROACH FROM THE WEST. ONSET OF
BETTER MID/HIGH LEVEL MOISTURE LIKELY TO BRING INCREASING CLOUDS
SATURDAY NIGHT BUT LIKELY THIN ENOUGH EARLY ON TO ALLOW TEMPS TO DIP
INTO THE 20S MOST SPOTS BUT STILL DRY. SYSTEM HEADS EAST TOWARD THE
REGION BUT QUITE DISORGANIZED INITIALLY WITH NORTHERN STREAM ENERGY
PASSING TO THE NW AND THE MAIN SOUTHERN STREAM WAVE STILL HANGING
BACK ALONG THE GULF COAST. SOME SOLUTIONS SUCH AS THE GFS REMAIN
FAST TO BRING SOME LEAD LIGHT PRECIP NE INTO THE AREA ON SUNDAY
WHILE OTHERS PER THE LATEST ECMWF QUITE SLOW WITH LITTLE PRECIP AT
ALL DURING THE DAY. GIVEN THE STRONG UPPER JET AND PAST HISTORY OF
WEAK LIFT SYSTEMS DEVELOPING PRECIP FASTER...LEFT IN SOME CHANCE
POPS SUNDAY AFTERNOON WITH SOME LIGHT SNOW...MAINLY FAR NW WHERE A
NAM/GFS MIX WOULD SUPPORT A MORE FROZEN SCENARIO. TEMPS TO WARM A
BIT UNDER WARM ADVECTION ALOFT IN ADVANCE OF THE INITIAL FRONT WITH
HIGHS MOSTLY 40S EXCEPT LOW 50S SE.
DIGGING/AMPLIFYING 5H TROUGH WILL START TO ARRIVE FROM THE NW LATER
SUNDAY NIGHT AND HELP ENHANCE MOISTURE COMING NE WITH THE SOUTHERN
SHORTWAVE. HOWEVER JUST HOW FAST THIS HAPPENS KEY TO PRECIP COVERAGE
SUNDAY NIGHT AS WELL AS THE TEMP PROFILE ALOFT GIVEN DECENT 85H WARM
ADVECTION. LATEST GFS FASTER BUT STILL HAS BEST LIFT CLOSER TO THE
BAROCLINIC ZONE ALONG THE APPALACHIANS AS WEAK SURFACE WAVES LIFT NE
INTO THE CAROLINAS LATE. NEW ECMWF MUCH SLOWER WITH THE SOUTHERN
SYSTEM LAGGING FARTHER SOUTH WHICH WOULD RESULT IN ONLY SPOTTY
PRECIP. FOR NOW KEPT LIKELY POPS FOR LATER SUNDAY NIGHT BUT WARMER
WITH PERHAPS ONLY THE HIGHER ELEVATIONS OVER THE FAR NW STAYING COLD
ENOUGH ALOFT FOR SNOW. OTRW LOWS STEADYING OUT IN THE 30S WEST TO
AROUND 40 SE.
&&
.LONG TERM /MONDAY THROUGH WEDNESDAY/...
AS OF 300 PM EST THURSDAY...
GENERAL FLAVOR OF MODEL GUIDANCE REMAINS THE SAME FOR THE EXTENDED
PERIOD AS A COLD FRONT MOVES THROUGH THE REGION SUNDAY NIGHT WITH A
WAVE RIDING UP ALONG THE FRONT FROM THE SOUTHEAST. LOW LEVEL WARM
AIR SURGING IN AHEAD OF THIS SYSTEM SHOULD HAVE PTYPE MOSTLY LIQUID
UNTIL COLD AIR PUSHES IN FROM THE NORTHWEST LATER ON MONDAY...AND WE
TRANSITION OVER TO SNOW AS BULK OF SYNOPTIC PCPN PULLS OUT. UPSLOPE
SNOW SHOWERS WILL THEN AFFECT AREAS WEST OF THE BLUE RIDGE MONDAY
NIGHT INTO TUESDAY WITH SOME ACCUMULATIONS POSSIBLE FOR THE WESTERN
SLOPES. MAY SEE AN UPTICK IN SNOW SHOWERS TOWARD DAYBREAK TUESDAY AS
A VIGOROUS SHORT WAVE MOVES SWINGS THROUGH THE BASE OF THE UPPER
TROF AND PASSES OVER THE REGION. HIGH PRESSURE WILL THEN PUSH IN
FROM THE SOUTHEAST AS MOISTURE RETREATS AND WE ARE QUIET AND COLD
FOR LATE TUESDAY INTO WEDNESDAY. HIGH PRESSURE SLIDES OFF TO OUR
EAST THURSDAY...ALLOWING SOUTHERLY RETURN FLOW TO MODERATE
TEMPERATURES A BIT BEFORE WE SEE AFFECTS OF NEXT SYSTEM APPROACHING
FROM THE MISSISSIPPI VALLEY THURSDAY NIGHT.
IT LOOKS LIKE MONDAY NIGHT THROUGH TUESDAY NIGHT WILL SEE THE BEST
CHANCES FOR WINDY CONDITIONS WITH GOOD DOWNWARD MOMENTUM TRANSFER
ABLE TO BRING STRONG LOW LEVEL WINDS TO THE SURFACE.
&&
.AVIATION /20Z THURSDAY THROUGH TUESDAY/...
AS OF 1235 PM EST WEDNESDAY...
MAINLY MVFR CONDITIONS ACROSS THE REGION CURRENTLY FOR CEILING
HEIGHT. THE REMAINDER OF THE AFTERNOON THROUGH THE EARLY
EVENING...A DISTURBANCE WILL CROSS THE REGION AND BRING SOME LIGHT
PATCHY LIGHT RAIN...LIGHT SLEET OR LIGHT SNOW ACROSS...WITH THE
BEST CHANCE FOR LIGHT FROZEN PRECIPITATION ACROSS THE MOUNTAINS.
FLIGHT CATEGORIES WILL REMAIN PRIMARILY MVFR WITH SOME POCKETS OF
IFR FOR CIGS AND MVFR FOR VSBYS.
THE DISTURBANCE WILL EXIT THE REGION AROUND 04Z/11PM THIS EVENING
TAKING THE PATCHY LIGHT PRECIPITATION WITH IT. NORTHWEST WINDS
WILL GRADUALLY INCREASE THIS EVENING WITH SOME GUSTS AROUND
15-20KT. CIGS WILL SHOW ONLY GRADUAL IMPROVEMENT THE REMAINDER OF
THE NIGHT THROUGH THE FORENOON FRIDAY. CONDITIONS WILL IMPROVE THE
MOST RAPIDLY EAST OF THE CREST OF THE BLUE RIDGE THANKS TO A
DOWNSLOPING COMPONENT.
EXTENDED DISCUSSION...
AN UPPER LEVEL TROUGH WILL DEVELOP OVER THE EASTERN U.S. AND MAKE
ITS WAY NORTHEAST THROUGH SATURDAY. ARCTIC HIGH PRESSURE WILL KEEP
MOST AREAS VFR FRIDAY AND SATURDAY. THE EXCEPTION MAY BE SOME LATE
NIGHT RIVER OR VALLEY FOG AND LINGERING UPSLOPE CLOUDS AND
POSSIBLY -SHSN AT KBLF/KLWB INTO FRIDAY MORNING.
ON SUNDAY INTO MONDAY...A STRONG UPPER WAVE AND ASSOCIATED COLD
FRONT IS EXPECTED TO MOVE INTO AND/OR THROUGH THE REGION. THIS MAY
BRING SUB-VFR CONDITIONS AND A WINTRY MIX OF PRECIPITATION. MODELS
ARE COMING IN WARMER...SO THE TREND IS FOR MORE RAIN AND LESS
WINTER PRECIPITATION THREAT. MOST WINTER PRECIPITATION SHOULD BE
CONFINED TO THE MOUNTAINS...IMPACTING KLWB/KBLF TO SOME
EXTENT...BUT BY NO MEANS A SIGNIFICANT WINTER EVENT. MORE
WIDESPREAD -SHSN EXPECTED BEHIND THE FRONT MON NIGHT INTO TUE WITH
SOME ACCUMULATIONS POSSIBLE AT THAT TIME...AGAIN MAINLY IMPACTING
BLF/LWB. GUSTY NORTHWEST WINDS ARE EXPECTED BEHIND THE SYSTEM ON
TUESDAY.
&&
.CLIMATE...
RECORD COOLEST HIGHS
FRI NOV 14TH
BLACKSBURG VA...35 IN 1986
BLUEFIELD WV....29 IN 1975
DANVILLE VA.....39 IN 1997
ROANOKE VA......37 IN 1976
LEWISBURG WV....30 IN 1975
LYNCHBURG VA....37 IN 1996
SAT NOV 15TH
BLACKSBURG VA...32 IN 1976
BLUEFIELD WV....23 IN 1969
DANVILLE VA.....41 IN 1986
ROANOKE VA......34 IN 1969
LEWISBURG WV....29 IN 1995
LYNCHBURG VA....36 IN 1969
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...DS
NEAR TERM...DS
SHORT TERM...JH
LONG TERM...MBS
AVIATION...DS
CLIMATE...DS
YOU CAN SEE AN ILLUSTRATED VERSION OF THIS FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
1044 AM CST THU NOV 13 2014
.UPDATE...
AN UPPER LEVEL TROUGH WILL VERY SLOWLY SWING THROUGH THE REGION
TODAY. THERE IS PERSISTENT BUT VERY WEAK VORTICITY ADVECTION INTO
SOUTHERN WI WITH THIS UPPER TROUGH. PERIODS OF LIGHT SNOW OR LIGHT
SNOW SHOWERS OR SCATTERED FLURRIES /OR WHATEVER TERMINOLOGY YOU
WOULD LIKE TO USE/ WILL PERSIST THROUGH THE AFTERNOON. RADAR MOSAIC
SHOWS LIGHT RETURNS ALL ACROSS THE REGION WITH THE EXCEPTION OF EAST
CENTRAL WI WHERE THERE ARE BREAKS IN THE CLOUDS.
BUFKIT RAP SOUNDINGS SHOW STEEP LOW LEVEL LAPSE RATES WITHIN THE
DENDRITE GROWTH ZONE /DGZ/ THROUGH THE WHOLE AFTERNOON WITH THE
EXCEPTION OF OUR NORTH NEAR SHEBOYGAN WHERE THERE ARE DRIER
PROFILES. I DEBATED ABOUT WHAT TO DO ABOUT POPS AND WEATHER SINCE
THIS IS A HIGH-OCCURRENCE/TRACE EVENT. PER COLLABORATION WITH
SURROUNDING OFFICES... WE ARE HANDLING THIS LIGHT SNOW WITH HIGH
POPS AND DEFINITE LIGHT SNOW OR SOMETHING SIMILAR.
&&
.AVIATION/18Z TAFS/...
LINGERING LOW LEVEL RH AND PASSING WEAK DISTURBANCES WL RESULT IN
MVFR CLOUDS AT TIMES AND PERSISTENT LIGHT SNOW/FLURRIES TODAY INTO
THIS EVENING. CLOUDS SHOULD ERODE AND BECOME MORE WIDESPREAD VFR
LATE TNGT INTO FRI MRNG.
&&
.PREV DISCUSSION... /ISSUED 327 AM CST THU NOV 13 2014/
TODAY AND TONIGHT... FORECAST CONFIDENCE - MEDIUM.
AREA OF MID-LEVEL SHEAR VORTICITY WL PASS OUT OF SOUTHEAST WI EARLY
THIS MRNG AS FLURRIES CONTINUE TO DIMINISH OVER THE SOUTH. LOW LEVEL
MOISTURE WILL LINGER OVER SRN WI INTO TNGT WITH EVEN A SLIGHT
INCREASE IN THE MID LEVELS. SATELLITE IMAGERY AND VWP NETWORK
SHOWING SECONDARY UPSTREAM MID-LEVEL CIRCULATION OVER NW WI/E
CENTRAL MN REGION. SHORT TERM GUIDANCE IN GOOD AGREEMENT ON
SWINGING THIS WEAK SHORT WAVE SOUTHWARD ACROSS SRN WI LATER THIS
MRNG AND AFTN. SLIGHTLY DEEPER COLUMN RH WL ONCE AGAIN BE ABLE TO
TAP INTO DENDRITIC GROWTH ZONE AS WEAK LIFT PASSES THRU. HENCE WL
CONTINUE 20-30 PERCENT POPS. PAVEMENT TEMPS NOW BELOW FREEZING SO A
LIGHT DUSTING WL BE POSSIBLE.
LINGERING FLURRIES POSSIBLE THIS EVENING BEFORE INCREASING
SUBSIDENCE FROM UPSTREAM SHORT WAVE RIDGING SETTLES IN LATE TNGT
INTO FRI. CLOUDS MAY HANG ON INTO FRI MRNG.
FRIDAY...FORECAST CONFIDENCE...HIGH
SURFACE HIGH PRESSURE WILL MOVE OVERHEAD FRIDAY...BRINGING A FAIR
AMOUNT OF SUNSHINE BY AFTERNOON AS DRIER LOW LEVEL AIR ARRIVES.
THE SUNSHINE WILL NOT PUT MUCH OF A DENT IN THE COLD AIR
THOUGH...WITH HIGHS STRUGGLING INTO THE UPPER 20S MOST PLACES.
SATURDAY...FORECAST CONFIDENCE...MEDIUM
MODELS REMAIN IN GOOD AGREEMENT WITH A SHORTWAVE SLIDING THROUGH
SATURDAY NIGHT INTO SUNDAY MORNING. THOUGH THERE IS NOT A TON OF
MOISTURE AND LIFT WITH THIS SYSTEM...FAIRLY DEEP SATURATION OCCURS
FOR A TIME...WITH THE DENDRITE GROWTH ZONE VIA MODEL SOUNDINGS
ABOUT 250-300 MB DEEP DURING THE PERIOD OF BEST LIFT. BEST
Q-VECTOR CONVERGENCE AND DEEPEST SATURATION IS EXPECTED SAT
EVENING AND OVERNIGHT...WHEN AROUND AN INCH OR TWO OF SNOW IS
POSSIBLE.
SUNDAY THROUGH WEDNESDAY...FORECAST CONFIDENCE...MEDIUM
SNOW IS EXPECTED TO WIND DOWN SUNDAY MORNING...WITH UPPER TROUGHING
REMAINING OVER THE AREA THROUGH WEDNESDAY. WILL SEE A FEW EMBEDDED
SHORTWAVES SLIDE THROUGH WHICH WILL BRING FLURRIES AT TIMES...BUT
NOT SEEING ENOUGH MOISTURE/LIFT WITH THESE WEAK WAVES TO CONSIDER
ADDING SLIGHT CHANCE POPS.
THE COLD AIR IS EXPECTED TO REMAIN IN PLACE THROUGH AT LEAST THE
FIRST HALF OF NEXT WEEK. TEMPS EARLY NEXT WEEK MAY BE EVEN A BIT
COLDER THAN THIS WEEK...WITH FORECAST HIGHS ABOUT 15 TO 20 DEGREES
BELOW NORMAL.
AVIATION/12Z TAFS/...
LINGERING LOW LEVEL RH AND PASSING WEAK DISTURBANCES WL RESULT IN
MORE MVFR CLOUDS AT TIMES AND ISOLD -SHSN/FLURRIES TODAY INTO THIS
EVENING. CLOUDS SHOULD ERODE AND BECOME MORE WIDESPREAD VFR LATE
TNGT INTO FRI MRNG.
MARINE...
WIND GUSTS ARE EXPECTED TO REMAIN MOSTLY BELOW 22 KNOTS THROUGH
TONIGHT DESPITE SECONDARY WEAK SURGE OF LOW LEVEL COLD AIR MOVING
ACROSS WARMER LAKE MI WATERS. FEW GUSTS TO 22 KNOTS MAY AFFECT
SGNW3 BUT FOR THE MOST POINT BORDERLINE SITUATION WITH MOST GUSTS
REMAINING BELOW ADVY LEVELS.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
UPDATE...MRC
TODAY/TONIGHT AND AVIATION/MARINE...MBK
FRIDAY THROUGH WEDNESDAY...DDV
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1042 PM MST FRI NOV 14 2014
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 232 PM MST FRI NOV 14 2014
...ACTIVE WEATHER CONTINUES...
CURRENT WATER VAPOR IMAGERY AND UPPER AIR ANALYSIS INDICATING
MODERATE TO STRONG WESTERLY FLOW ALOFT ACROSS THE REGION WITH
ANOTHER EMBEBBED SHORT WAVE TRANSLATING ACROSS THE GREAT BASIN AND
INTO WESTERN COLORADO. REGIONAL SATELLITE AND RADAR DATA INDICATING
A GOOD SLUG OF MOISTURE MOVING INTO WESTERN COLORADO ALONG WITH A
FEW LIGHTNING STRIKES ACROSS SOUTHEASTERN UTAH AT THIS TIME.
TEMPERATURES AS OF 2 PM INDICATING SHALLOW COLD AIRMASS PERSISTING
ACROSS SOUTHERN EL PASO COUNTY AND THE LOWER ARKANSAS RIVER VALLEY
FROM CANON CITY TO LAMER...WITH TEMPS IN THE 20S TO LOWER 30S AT
THIS TIME. ELSEWHERE ACROSS THE AREA...TEMPS HAVE WARMED INTO THE
40S TO LOWER 50S WITH MAINLY 20S AND 30S ACROSS THE CONTDVD.
TONIGHT...MODELS CONTINUE TO BRING WAVE ACROSS THE AREA WITH
MODERATE TO HEAVY SNOWFALL EXPECTED ACROSS THE CENTRAL AND SOUTHWEST
MTS AND ACROSS THE HIGHER ELEVATIONS OF THE SANGRE DE CRISTO MTS
THROUGH EARLY SATURDAY MORNING. CURRENT WINTER WEATHER HIGHLIGHTS
LOOK ON TRACK WITH 4 TO 8 INCHES POSSIBLE OVERNIGHT. MODELS...TO A
VARYING DEGREE...CONTINUE TO INDICATE A BAND OF PRECIPITATION...
MOVING INTO THE LA GARITA MTS AT THIS TIME...CONTINUING TO SPREAD
EAST ACROSS THE NORTHERN SAN LUIS VALLEY AND ACROSS THE LOWER
ARKANSAS RIVER THROUGH THE LATE EVENING AND OVERNIGHT HOURS. WHILE
THE 18Z NAM LOOKS HEAVY HANDED IN QPF...RAP AND HRRR HAVE A
SIMILAR SET UP AND HAVE INCREASED POPS ACROSS THIS AREA TO MATCH
KEEPING ACCUMULATIONS OF AN INCH OR LESS AT THIS TIME.
HOWEVER...WILL NEED TO CONTINUE TO MONITOR THE DEVELOPMENT OF THIS
BAND AS THE 18Z NAM IS GIVING UP TO 3 INCHES ACROSS THE LOWER ARK
VALLEY TONIGHT. WITH EXPECTED CLOUD COVER...EXPECTING LOWS TO BE
MAINLY IN THE 20S ACROSS THE AREA.
TOMORROW...MODELS CONTINUE TO DIFFER ON TIMING OF THE NEXT SLUG OF
ARCTIC AIR TO INVADE EASTERN COLORADO...ESPECIALLY ITS ASSOCIATED
PRECIPITATION FIELD. NAM AND EC CONTINUE TO BE SLOWER WITH THE
UPPER TROUGH MOVING ACROSS THE ROCKIES WITH THE GFS REMAINING
FASTER. AT ANY RATE...HAVE PLAYED THE TIMING OF THE ARCTIC FRONT
ACROSS THE PALMER DVD AROUND 18Z...THOUGH HAVE DELAYED ONSET OF
PRECIPITATION INTO THE LATE AFTERNOON. GUSTY NORTH TO NORTHEAST
WINDS OF 20 TO 30 MPH TO ANNOUNCE THE ARRIVAL OF THE FRONT...WHICH
MAY BE ENOUGH TO BRIEFLY MIX OUT THE SHALLOW COLD AIRMASS IN PLACE
ACROSS THE LOWER ARK VALLEY...BEFORE TEMPS COOL AGAIN BEHIND THE
FRONT. NEEDLESS TO SAY...FORECASTING HIGH TEMPERATURES TOMORROW
WILL AGAIN BE A CHALLENGE.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 232 PM MST FRI NOV 14 2014
...SNOW CONTINUES SATURDAY NIGHT THROUGH SUNDAY...
UPPER TROF WILL DROP IN FROM THE NORTHWEST SATURDAY NIGHT BRINGING
A HEALTHY BOUT OF UPPER FORCING ACROSS THE AREA IS IT DROPS TO THE
SOUTHEAST. THERE ARE STILL SOME TIMING DIFFERENCES IN THE MODELS
WITH THE ONSET OF THE PRECIPITATION...ESPECIALLY FOR THE SOUTHEAST
MTS/PLAINS. GFS IS A TOUCH FASTER WITH THE SOUTHWARD PROGRESSION
OF THE UPPER TROF...WHICH MAY BE THE REASON IT IS TRENDING FASTER
WITH THE ONSET OF PRECIPITATION VS THE SLOWER NAM12 AND ECMWF.
FRONT WILL HAVE ALREADY BLASTED THROUGH SOUTHEAST CO BY 00Z
SUN...AND GIVEN ITS ARCTIC ORIGIN...THIS TIMING LOOKS REASONABLE.
HOWEVER...WITH THE UPPER FORCING IS STILL WELL OFF TO THE NORTH
DURING THIS TIME PERIOD...AND A SLOWER TIMING TO THE ONSET OF
PRECIPITATION...ESP FOR THE SE PLAINS...SEEMS MORE REASONABLE.
NORTHEAST UPSLOPE BEHIND THE FRONT IS RATHER SHALLOW (BELOW H7) BUT
AS UPPER TROF DROPS IN FROM THE NORTHWEST...THERE WILL BE A PERIOD
OF UPGLIDE OVER THE COLD DOME DURING THE EVENING AND OVERNIGHT
HOURS. THE GFS SHOWS SOME PRETTY GOOD DIV-Q...THE CORE OF WHICH
PASSES ACROSS UT/THE 4 CORNERS REGION/SRN CO/AND NORTHERN NM. SO
ALTHOUGH UPSLOPE IS SHALLOW FOR THE SOUTHEAST MTS...AND NOT THE
BEST FOR THE SOUTHWEST MOUNTAINS WITH FLOW ALOFT MORE WESTERLY
(INSTEAD OF THE MORE FAVORABLE SOUTHWEST DIRECTION)...HAVE SEEN
THESE DYNAMIC SYSTEMS PRODUCE WIDESPREAD MODERATE TO HEAVY
SNOWFALL AMOUNTS. WITH TIMING OF THE FORCING EXITING SOUTHERN CO
AROUND OR SHORTLY AFTER 12Z SUN...PLAN TO KEEP THE HEADLINE TIMING
FOR THE CONTINENTAL DIVIDE AS IS FOR NOW. HOWEVER...IF MOISTURE
DIMINISHES RAPIDLY ENOUGH BEHIND THE TROF...ITS POSSIBLE THAT THE
SNOW MAY DECREASE A BIT SOONER FARTHER NORTH ACROSS THE SAWATCH
AND MOSQUITO RANGES. GIVEN THE INCONSISTENCIES BETWEEN
MODELS...WILL LET LATER SHIFTS REFINE THE TIMING AS NEED BE.
ADDITIONAL SNOWFALL AMOUNTS IN THE 4 TO 8 INCH RANGE LOOKS
REASONABLE ALONG THE CONTINENTAL DIVIDE SAT NIGHT GIVEN THE
PROBABILITY FOR 20+/1 LIQUID/SNOW RATIOS. STILL SOME UNCERTAINTY
FOR SNOWFALL AMOUNTS ACROSS THE SOUTHEAST MOUNTAINS...AS THE GFS
IS HEAVIER WITH QPF ACROSS THE PIKES PEAK REGION VS THE DRIER
NAM12. HUNCH IS THAT SOUTHEAST MOUNTAINS AND PORTIONS OF THE I-25
CORRIDOR MAY NEED AN ADVISORY SAT NIGHT...WITH THE WETS AND
SANGRES LIKELY TO SEE SOMEWHERE IN THE 3-8 INCH RANGE. TELLER AND
EL PASO COUNTIES STILL VERY MUCH IN THE AIR WITH NAM SUGGESTING
ONLY AN INCH OR TWO SAT NIGHT...WHILE GFS HAS 2 TO NEARLY 4
INCHES. GIVEN THE TRACK OF THE STRONGER FORCING ALOFT...IT DOES
MAKE SENSE THAT THE LIGHTER NAM12 AMOUNTS COULD BE MORE
REASONABLE. SUSPECT THAT SOME BANDING OF SNOW ALONG/SOUTH OF THE
ARKANSAS RIVER WILL EXTEND EASTWARD ACROSS THE SOUTHEAST
PLAINS...BUT SNOWFALL AMOUNTS AT THIS TIME APPEAR TO STAY BELOW
ADVISORY LEVELS...PERHAPS 1-3" RANGE. AGAIN GIVEN THE COLD AIRMASS
WITH THIS EVENT...IT SHOULD BE ANOTHER DRY FLUFFY SNOW EVENT. THE
DIFFERENCE THIS TIME WILL BE THAT THE ROAD SURFACES WILL START OUT
COLDER GIVEN OUR PREVIOUS COLD OUTBREAK. THIS COULD LIMIT THE
ICING FACTOR SOME DEPENDING ON ASPHALT TEMPERATURES SATURDAY
AFTERNOON.
SNOW WILL END FROM NORTH TO SOUTH DURING THE MORNING ON
SUNDAY...AND SNOW COVER WILL LIKELY KEEP TEMPERATURES FROM WARMING
MUCH. HAVE DROPPED HIGHS A FEW DEGREES FROM THE CONSENSUS
GRIDS...WHICH PUTS THEM CLOSER TO THE COLDER SIDE OF GUIDANCE
VALUES.
FORECAST DRIES OUT FOR THE REMAINDER OF THE EXTENDED. ANOTHER
SURFACE HIGH DESCENDS THROUGH THE PLAINS WITH SOME UNCERTAINTIES
AS TO HOW FAR WEST THE CORE OF COLD AIR ASSOCIATED WITH IT WILL
GET. NAM12 AND EC ARE SEVERAL DEGREES COOLER WITH H7 TEMPS ACROSS
THE PLAINS VS THE WARMER GFS MONDAY AFTERNOON...WHICH PUTS HIGH
TEMPERATURES IN QUESTION ACROSS THE PLAINS. CURRENT GRIDS ARE
CARRYING MID 20S TO AROUND 30...BUT THESE MAY NEED TO BE COOLED
OFF EVEN FURTHER DEPENDING ON HOW THIS EVOLVES.
NORTHERLY FLOW ALOFT GRADUALLY SHIFTS TO A MORE WESTERLY DIRECTION WHICH
SHOULD BRING SOME MODERATING TEMPERATURES THROUGH MID TO LATE
WEEK. ANOTHER PACIFIC SYSTEM MAY CUT THROUGH THE WESTERN U.S.
UPPER RIDGE TOWARDS FRIDAY. FORECAST WILL CARRY GENERALLY DRY
CONDITIONS UNTIL FRIDAY WITH TEMPERATURES WARMING BUT STILL
REMAINING BELOW NORMAL. -KT
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1042 PM MST FRI NOV 14 2014
PRIMARILY VFR CONDITIONS ARE ANTICIPATED AT THE KALS...KCOS AND
KPUB TAF SITES INTO SATURDAY AFTERNOON(OUTSIDE OF KALS...WHERE
SOME LOW CLOUDS WILL BE POSSIBLE AT TIMES TONIGHT). METEOROLOGICAL
CONDITIONS ARE THEN EXPECTED TO DETERIORATE FROM LATE SATURDAY
AFTERNOON INTO SATURDAY NIGHT...ESPECIALLY OVER THE KCOS AND KPUB
TAF SITES AS MOIST NORTH TO NORTHEASTERLY SURFACE FLOW DEVELOPS IN
THE WAKE OF A MODIFIED ARCTIC FRONT PROJECTED TO PUSH ACROSS THE
SOUTHEASTERN COLORADO PLAINS DURING SATURDAY AFTERNOON.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING UNTIL 5 AM MST SUNDAY FOR COZ058-060-066-
068.
WINTER WEATHER ADVISORY UNTIL 5 AM MST SATURDAY FOR COZ073-075.
&&
$$
AREA FORECAST DISCUSSION
NWS DES MOINES IA
303 AM CST SAT NOV 15 2014
.SHORT TERM /TODAY/...
ISSUED AT 303 AM CST SAT NOV 15 2014
NO MAJOR CHANGES WITH ONGOING FORECAST FOR THE FIRST
SIGNIFICANT SNOWFALL OF THE SEASON AS MODELS REMAIN IN GOOD
AGREEMENT WITH EXPECTED SNOW TODAY. USED A BLEND OF THE HRRR/HOPWRF
FOR TIMING OF PRECIP AND NAM/ECMWF TEMPS.
BROAD ISENTROPIC LIFT AND DECENT MOISTURE TRANSPORT DEVELOP OVER
WESTERN TO NORTHWEST IOWA THIS MORNING AND QUICKLY BLOSSOMS ACROSS
THE REMAINDER OF THE STATE THIS AFTERNOON. ONE MINOR CHANGE WAS
START THE SNOW A LITTLE SOONER THIS MORNING OVER THE WEST TO
NORTHWEST AS SNOW ALREADY DEVELOPING ALOFT AND SNOW SHOULD START
REACHING THE SURFACE BETWEEN 12-14Z THIS MORNING. THE 15.03Z HOPWRF
AND 15.05Z HRRR HAVE SNOW MOVING INTO THE WESTERN EDGES OF THE
FORECAST AREA BETWEEN 13-15Z. THE FORECAST SOUNDINGS ACROSS NORTHERN
IOWA BECOME COMPLETELY SATURATED BY 17-18Z TODAY AND THE STRONGER
OMEGA IS JUST AT THE TOP EDGE OF THE DENDRITIC LAYER BUT ENOUGH
OVERLAP TO SEE SOME DECENT FLAKES...AND THUS SLIGHTLY HIGHER SNOW
ACCUMULATION THIS AFTERNOON OVER NORTHERN IOWA. RAP IS A BIT LESS
WITH THE FORCING THAN THE NAM/GFS AND HAS SLIGHTLY LOWER SNOW
AMOUNTS GOING...BUT STILL DEPICTS ENOUGH SNOW TO WARRANT ADVISORY.
FURTHER SOUTH...SOUNDINGS NOT TOO DISSIMILAR THAN NORTHERN
IOWA...WITH THE MAIN DIFFERENCE BEING JUST SLIGHTLY LESSER FORCING
WITHIN THE DENDRITIC LAYER. THIS RESULTING IN LESS SNOW AMOUNTS OVER
THE SOUTHERN TWO-THIRDS OF THE FORECAST AREA.
LEANED TOWARD A BLEND OF THE WARMER NAM/ECMWF FOR TEMPERATURES
TODAY. THIS RESULTED IN SNOW RATIOS AROUND 17:1 TO 18:1 OVER NORTHERN
IOWA AND 15:1 TO 16:1 ACROSS THE SOUTH...BASED ON 925M TO 700MB
THICKNESS. HAVE 100 POPS GOING MUCH OF THE AFTERNOON WITH HIGH
CONFIDENCE ALL OF CENTRAL IOWA WILL BE SNOWING BY OR SHORTLY PAST
18Z. VERY LITTLE WIND TODAY BUT WITH THE FLUFFY SNOW TYPE EXPECTED
AND AT TIMES FALLING MODERATELY...THIS SHOULD BE ENOUGH TO CAUSE
SOME VISIBILITY RESTRICTION WITH A 6-9 KNOT WIND.
.LONG TERM /TONIGHT THROUGH FRIDAY/...
ISSUED AT 303 AM CST SAT NOV 15 2014
ACTIVE WEATHER WILL CONTINUE THROUGH THE WEEKEND AND EARLY NEXT WEEK
FOLLOWING TONIGHTS SYSTEM...ANOTHER INTENSE UPPER LEVEL LOW WILL
DROP SOUTH INTO THE NORTHERN GREAT LAKES SUNDAY NIGHT AND MONDAY
MORNING. TONIGHT...SYSTEM EXITING THE AREA TO THE EAST DURING THE
EVENING HOURS. BEST FORCING ALONG H500 AND SFC TROUGH NEAR 00Z
FOCUSING ON H700 BOUNDARY ACROSS NORTHERN IOWA. THROUGH 06Z THIS
H700 BOUNDARY PUSHES EAST WITH TROUGH RESULTING IN LESSENING FORCING
WEST OF I35 DURING THE LATE EVENING. BY 12Z BEST FORCING EAST OF THE
AREA WITH SOME RESIDUAL LIGHT SNOW/FLURRIES OVER THE NORTHEAST
ENDING QUICKLY WITH CLOUDS DEPARTING IN THE MORNING SUNDAY. SNOW
RATIOS OF 18 TO 20:1 AND EXPECTED QPF AMOUNT YIELD SNOWFALL
AMOUNTS OF UP TO ANOTHER 1.5 INCHES TONIGHT DURING THE EVENING AND
OVERNIGHT HOURS. FORTUNATELY THE WINDS WILL BE LIGHT DURING THE
EVENT...SO BLOWING SNOW WILL NOT BE AN ISSUE TONIGHT. WITH
CLEARING BY MORNING...LOWS WILL QUICKLY FALL NORTHWEST AND WEST
INTO THE SINGLE DIGITS WITH TEENS I35 EAST. SUNDAY WILL INITIALLY
SEE SOME SUNSHINE BETWEEN WAVES BUT CLOUDS WILL INCREASE WEST
DURING THE AFTERNOON. WITH H850 TEMPS IN THE -10C TO -12C RANGE
AND WESTERLY WINDS...TEMPERATURES WILL BE TOLERABLE IN THE MID 20S
OVER MOST OF THE AREA. AN APPROACHING COLD FRONT WILL SPREAD
CLOUDS ACROSS THE REGION THROUGH EARLY EVENING. THE SECOND STRONG
H500 LOW WILL FORCE A BULGE OF COLD AIR QUICKLY SOUTHEAST INTO
WESTERN IOWA SUNDAY EVENING WITH RATHER STRONG COLD AIR ADVECTION
AND INCREASING WINDS ALOFT. BY 12Z H850 TEMPS WILL HAVE FALLEN
ANOTHER 8 TO 10C WITH READINGS FROM -16C TO -20C. THROUGH THE DAY
MONDAY CLOUD COVER WILL OVERTAKE THE AREA WITH H850 TEMPS SETTLING
TOWARD -18C TO -20C REGION WIDE. MODELS HAVE BEEN CONSISTENT WITH
STEEPENING LAPSE RATES NEAR 15Z AND STRONG MIXING THROUGH THE
DAY...POTENTIAL FOR SNOW SHOWERS ACROSS THE NORTHEAST WITH
FLURRIES CENTRAL AND SOUTH. ALL IN ALL...MONDAY IS LOOKING RATHER
UNPLEASANT. POTENTIAL FOR 15 TO 25 MPH WINDS WITH GUSTS TO NEAR 35
MPH AT TIMES. THIS WILL CAUSE PATCHY TO AREAS BLOWING SNOW OVER
MUCH OF THE NORTHEAST HALF OF THE AREA WITH REDUCTIONS TO
VISIBILITY. HEADLINES MAY BE NEEDED AGAIN ON MONDAY FOR THE
COMBINATION OF WIND...BLOWING SNOW...AND COLD. HAVE EXPANDED THE
POTENTIAL FOR LIGHT PRECIP AND BLOWING SNOW MONDAY ACROSS THE
AREA. HIGHS WILL RECOVER LITTLE FROM FRIGID MORNING LOWS IN THE
SINGLE DIGITS TO LOWER TEENS. BY AFTERNOON HIGHS NORTH WILL REACH
THE LOWER TEENS TO THE LOWER 20S IN THE SOUTHEAST. TO TOP OFF THE
WONDERFUL DAY...MINIMUM RECORD HIGHS LOOK LIKELY TO BE SET AT MANY
LOCATIONS...ONE WHICH HAS NOT BEEN SEEN SINCE THE 1890S AND MANY
SINCE THE 1950S. IN FACT...OUR HIGHS MONDAY WOULD STILL BE ABOUT
10 TO 15 DEGREES BELOW OUR COLDEST AVERAGE HIGHS FOR THE NORMALLY
COLDEST WINTER DAY OF THE YEAR...OR ABOUT 30 DEGREES BELOW OUR
NORMAL FOR 11/17. WE HAVENT HAD HIGHS THIS COLD SINCE EARLY MARCH
OF 2014. TUESDAY WILL BEGIN QUITE COLD WITH A RIDGE JUST EDGING
INTO THE AREA BUT WARM BY AFTERNOON. QUICKLY ANOTHER CLIPPER OVER
THE NORTHERN PLAINS WILL MODERATE THE AIRMASS WITH BRISK WEST
WINDS DEVELOPING DURING THE DAY. TEMPS WILL RISE INTO THE 20S.
ANOTHER ARCTIC FRONT WILL DROP SOUTH INTO THE AREA TUESDAY NIGHT
BUT THE AIRMASS WILL NOT BE QUITE AS COLD AS THE PREVIOUS. THE
REMAINDER OF THE WEEK FEATURES A SERIES OF ARCTIC SHORT WAVES
ROTATING AROUND THE HUDSON BAY PARENT H500 LOW...PULLING
ADDITIONAL COLD AIR TOWARD THE GREAT PLAINS. NEXT WEEK WILL
FEATURE DAYS WITH CLOUD COVER MIXED WITH SOME SUNSHINE AND CHILLY
READINGS. FORTUNATELY BY LATE IN THE EXTENDED...TOWARD SATURDAY
THE CROSS POLAR FLOW CUTS OFF...THE H500 RIDGE ACROSS THE WEST
COAST BREAKS DOWN AND MORE ZONAL FLOW RESULTS OVER THE ROCKIES.
THIS WILL CAUSE CHINOOK COMPRESSIONAL HEATING OVER THE PLAINS AND
MODERATE HIGHS TO ABOVE FREEZING. FROM WEDNESDAY THROUGH FRIDAY
HIGHS WILL APPROACH THE 30 DEGREE MARK WITH LOWS MODERATING INTO
THE TEENS OVER THE AREA. LITTLE PRECIPITATION IS EXPECTED FOR MUCH
OF THE PERIOD NEXT WEEK.
&&
.AVIATION...15/06Z
ISSUED AT 1121 PM CST FRI NOV 14 2014
BROAD AREA OF SN WILL PUSH EAST INTO SITES BEGINNING AFTER 12Z. SN
WILL PERSIST AT SITES THROUGH MAJORITY OF PERIOD. CEILINGS AND
VISIBILITIES WILL DROP TO MVFR AND TO IFR AT TIMES...ESPECIALLY
WITH FALLING SNOW. SYSTEM WILL PUSH QUICKLY EAST AND MAY SEE
VISIBILITIES IMPROVE AT WESTERN SITES...KFOD/KDSM BY END OF
PERIOD BUT LOW MVFR OR IFR CEILINGS WILL REMAIN.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 9 AM THIS MORNING TO MIDNIGHT CST
TONIGHT FOR ADAIR-ADAMS-APPANOOSE-AUDUBON-BLACK HAWK-BOONE-
BREMER-BUTLER-CALHOUN-CARROLL-CASS-CERRO GORDO-CLARKE-CRAWFORD-
DALLAS-DAVIS-DECATUR-EMMET-FRANKLIN-GREENE-GRUNDY-GUTHRIE-
HAMILTON-HANCOCK-HARDIN-HUMBOLDT-JASPER-KOSSUTH-LUCAS-MADISON-
MAHASKA-MARION-MARSHALL-MONROE-PALO ALTO-POCAHONTAS-POLK-
POWESHIEK-RINGGOLD-SAC-STORY-TAMA-TAYLOR-UNION-WAPELLO-WARREN-
WAYNE-WEBSTER-WINNEBAGO-WORTH-WRIGHT.
&&
$$
SHORT TERM...PODRAZIK
LONG TERM...REV
AVIATION...AWB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
417 AM EST SAT NOV 15 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 416 AM EST SAT NOV 15 2014
A QUIET START TO THE SHORT TERM FORECAST THIS MORNING...AS THE AREA
IS ON THE NORTHEAST EDGE OF A HIGH CENTERED FROM THE MID/UPPER
MISSISSIPPI VALLEY TO THE OHIO RIVER VALLEY. THIS HAS LED TO A
CLEAR AND COLD NIGHT ACROSS AT LEAST HALF OF THE CWA. WHERE WINDS
HAVE DECOUPLED (GENERALLY ACROSS THE INTERIOR WEST AND NEAR THE
WISCONSIN BORDER)...TEMPERATURES HAVE FALLEN INTO THE SINGLE
DIGITS BELOW ZERO. MEANWHILE...OVER THE CENTRAL AND EAST WHERE THE
WINDS HAVE BEEN STAYING UP...TEMPERATURES HAVE BEEN IN THE UPPER
SINGLE DIGITS ABOVE ZERO TO MID TEENS.
OVER LAKE SUPERIOR AND THE KEWEENAW...COLD AIR CONTINUING TO FLOW
OVER THE RELATIVELY WARM WATERS OF LAKE SUPERIOR WAS PRODUCING
MAINLY LAKE EFFECT CLOUDS THIS PAST EVENING AND INTO THE EARLY
OVERNIGHT HOURS. BUT STARTED SEEING WEAK LAKE EFFECT BANDS
OVER EASTERN LAKE SUPERIOR ON THE CANADIAN RADAR AT MONTREAL RIVER
SHORTLY AFTER MIDNIGHT. INVERSION IS RIGHT AT 875-850MB ON 00Z
KGRB/KINL SOUNDINGS AND THE LIMITED MOISTURE ON THE NORTH EDGE OF
THE HIGH HAVE BEEN THE MAIN LIMITING FACTORS TO LAKE EFFECT SNOW
EARLY THIS MORNING. KMQT VWP HAS BEEN SHOWING THE WINDS A LITTLE
MORE OUT OF THE WEST-NORTHWEST AND CONTRIBUTING TO THE LAKE EFFECT
CLOUDS NOSING SOUTHEAST INTO BARAGA...SOUTHERN HOUGHTON...AND EVEN
FAR NORTHERN IRON COUNTY EARLY THIS MORNING. BUT AS WE HEAD INTO
THE MORNING HOURS...MODELS SHOWING THE WINDS GOING BACK TO A MORE
WESTERLY AND POTENTIALLY WEST-SOUTHWESTERLY DIRECTION AND CONFINING
THE LAKE EFFECT CLOUDS AND SNOW POTENTIAL TO THE KEWEENAW AND OFF
THE SHORELINE FROM GRAND MARAIS EASTWARD. THIS WILL ALSO BE AIDED
BY THE LAND BREEZE THAT HAS DEVELOPED ALONG THE EASTERN U.P.
SHORELINE AND WILL AID IN KEEPING THE BANDS OFFSHORE THERE. THE
COVERAGE OF THE SHOWERS IS A LITTLE BIT OF A CONCERN DUE TO THE
LIMITED MOISTURE...BUT WOULD EXPECT SOME UPTICK IN THE SNOW SHOWERS
AS 875MB TEMPERATURES FALL FROM -11C ON THE RAP ANALYSIS TO -13/-14C
BY THIS AFTERNOON. THUS...WILL CONTINUE TO SHOW POPS RAMPING UP TO
HIGH CHANCES OVER THE KEWEENAW. WITH MUCH OF THE LAKE EFFECT CLOUD
BELOW THE DGZ...WILL KEEP SNOW RATIOS ON THE LOW END FOR LAKE EFFECT
AND ONLY HAVE ACCUMULATIONS AT A DUSTING TO AN INCH IN THAT AREA.
OVER THE REST OF THE AREA...EXPECT A SUNNY START TO THE DAY WHICH
WILL ALLOW TEMPERATURES TO RISE TO THE LOW-MID 20S THIS AFTERNOON.
EXPECT MORE OF A FILTERED SUNSHINE IN THE AFTERNOON AS HIGH CLOUDS
MOVE IN AHEAD OF THE WAVE BRUSHING THE AREA LATE TONIGHT.
HEADING INTO TONIGHT...FOCUS TURNS TO THE SHORTWAVE CURRENTLY
MOVING THROUGH WYOMING. THIS WAVE WILL QUICKLY SHIFT EAST THROUGH
NEBRASKA AND SOUTH DAKOTA TODAY AND THEN LIFT NORTHEAST ACROSS
NORTHERN LAKE MICHIGAN LATE TONIGHT AND SUNDAY MORNING. EXPECT THE
HIGH CLOUDS TO THICKEN THIS EVENING AND MID CLOUDS TO MOVE IN
DURING THE LATE EVENING AND OVERNIGHT. ANOTHER SHORTWAVE (CURRENTLY
IN COLORADO) WILL LIFT NORTHEAST OUT AHEAD OF THE MAIN WAVE AND
COULD PRODUCE A FEW SHOWERS AROUND MIDNIGHT. THE BETTER/MAIN
FORCING (GENERALLY ABOVE 700MB) COMES FROM THE SECOND SHORTWAVE AND
LOOKS TO STAY SOUTHEAST OF THE AREA...BUT DO EXPECT MENOMINEE COUNTY
AND AREAS ALONG THE LAKE MICHIGAN SHORELINE TO SEE THE BEST
OPPORTUNITY FOR ACCUMULATING SNOW. CURRENT FORECAST HAS SNOWFALL
AMOUNTS UP TO AN INCH OVER SOUTHERN MENOMINEE COUNTY AND TAPERING
OFF TO A HALF INCH OR LESS SOUTH OF A LINE FROM IRON MOUNTAIN TO
MANISTIQUE. SINCE THE NORTHERN EDGE OF THE FORCING WILL BE JUST
BRUSHING THE AREA...DO EXPECT A SHARP CUTOFF TO THE PRECIPITATION TO
THE NORTHWEST AND KEEP THE SNOW CHANCES TO THE SOUTHEAST OF A LINE
FROM MARQUETTE TO WATERSMEET. AS FOR THE LAKE EFFECT OVER THE
KEWEENAW...THIS WAVE WILL BACK THE LOW LEVEL WINDS FARTHER TO THE
SOUTHWEST AND FOCUS ANY LINGERING LAKE EFFECT TO THE FAR NORTHERN
PORTIONS OF THE KEWEENAW PENINSULA. ACCUMULATIONS WILL REMAIN LIGHT
AND BELOW 2 INCHES.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 409 AM EST SAT NOV 15 2014
A HI AMPLITUDE PATTERN FEATURING A TROF OVER CENTRAL AND ERN
NAMERICA DOWNSTREAM OF A RDG ALONG THE W COAST WL DOMINATE THE WX
PATTERN THIS COMING WEEK...LEADING TO PERSISTENT BLO TO WELL BLO
NORMAL TEMPS THRU THE WEEK. THE MOST SGNFT WX CONCERN WL BE THE
IMPACT OF A POTENT SHRTWV THAT IS FCST TO DIG SEWD THRU THE UPR LKS
EARLY IN THE WEEK AND AMPLIFY THE TROF. THIS DISTURBANCE WL ALMOST
CERTAINLY BRING ANOTHER ROUND OF MODERATE TO HEAVY LES AND SOME BLSN
MAINLY TO THE NW WIND SN BELTS NEAR LK SUP ON MON INTO TUE. YET
ANOTHER DISTURBANCE DIGGING THRU THE UPR TROF MAY BRING MORE SGNFT
LES ON WED INTO THU.
SUN...ONGOING LIGHT SN OVER THE SE CWA WL END BY EARLY IN THE AFTN
AS SHRTWV OVER ERN WI AT 12Z AND ACCOMPANYING DYNAMIC FORCING/
DEEPER MSTR EXIT TO THE E THRU LOWER MI AND INTO FAR SE ONTARIO IN
THE AFTN. AXIS OF DRIER AIR/DEEP LYR QVECTOR DVGC BTWN THIS
DEPARTING SHRTWV AND ANOTHER MORE POTENT SHRTWV DIGGING SE THRU
SCENTRAL CANADA WL THEN BRING A PERIOD OF DRY WX TO THE CWA.
ALTHOUGH H85 TEMPS ARE FCST TO BE AS LO AS -12 TO -13C...THE FCST
230 DEGREE LLVL FLOW IN ADVANCE OF THE APRCHG SHRTWV WL HOLD ANY LES
MAINLY TO THE NW OF THE KEWEENAW PENINSULA AND E OF LUCE/SCHOOLCRAFT
COUNTIES. ALTHOUGH DPVA/DEEP LYR QVECTOR CNVGC IN ADVANCE OF THE
INCOMING SHRTWV ARE FCST TO INVADE THE WRN CWA LATER IN THE DAY...
THE ABSENCE OF ANY SGNFT LLVL MSTR INFLOW WL MAINTAIN DRY WX THRU
00Z MON UNDER INCRSG HI/MID CLDS.
SUN NIGHT...INCOMING SHRTWV/SFC LO ARE FCST TO DRIFT OVER NRN LK SUP
BY 12Z MON AND CAUSE 12HR H5 HGT FALLS UP TO 120M ACROSS THE UPR
LKS. AXIS OF DPVA/DEEP LYR QVECTOR CNVGC WITHIN THE COMMA TAIL OF
THIS FEATURE ARE FCST TO SWING ACROSS UPR MI. HOWEVER...POTENTIAL
FOR WIDESPREAD SN IN ADVANCE OF THE SHRTWV WL BE LIMITED BY THE
ABSENCE OF LLVL MOISTENING/PWAT UNDER 0.25 INCH/H7 SPECIFIC HUMIDITY
NO MORE THAN ABOUT 1 G/KG. STILL LOOKS LIKE THE LLVL FLOW WL NOT
BACK SUFFICIENTLY TO ALLOW ANY LK ENHANCED OFF LK MI TO IMPACT LUCE
OR SCHOOLCRAFT COUNTIES. THE BEST CHC FOR MORE WIDESPREAD/HEAVIER
SNOW WL BE OVER THE W MAINLY LATE FOLLOWING COLD FROPA AND WIND
SHIFT TO AN UPSLOPE NW DIRECTION. ARRIVAL OF H85 TEMPS AROUND -15C
WITH SHARP CYC FLOW/LINGERING DEEP MSTR UNDER THE FALLING HGTS WILL
WARRANT KEEPING LIKELY TO CATEGORICAL POPS OVER THE W. WL GO NO HIER
THAN CHC POPS ELSEWHERE...WITH THE LOWEST SCHC POPS OVER THE
SCENTRAL.
MON/MON NGT...AS THE UPR TROF DEEPENS INTO THE GREAT LKS AND A
CLOSED H5 LO FORMS...UPR MI IS FCST TO BE UNDER SHARP...CYC W
VEERING NW FLOW ON MON AND NNW-NW FLOW ON MON NGT. FCST SDNGS SHOW
DEEP MOISTURE/INSTABILITY AS H5 TEMPS DIP TOWARD -40C. GIVEN H85
TEMPS FALLING TO -16C TO -18C AND THE DEEP INSTABILITY/MOISTURE WITH
THE CYC LLVL FLOW...CATEGORICAL POPS ARE WARRANTED IN THE FAVORED SN
BELTS. GUSTY WINDS UNDER THE SHARP PRES GRADIENT/DESTABILIZATION WL
CAUSE BLSN IN ADDITIONAL TO THE HEAVIER LES. FAVORABLE OMEGA PROFILE
WITHIN THE DGZ SITUATED BTWN ABOUT 1-5K FT AGL WL ALSO ENHANCE
SN/WATER RATIOS DESPITE THE IMPACT OF THE STRONG WINDS TO FRAGMENT
THE SN FLAKES. RIGHT NOW... THE FAR W IN ONTONAGON/GOGEBIC COUNTIES
LOOKS TO PICK UP THE HEAVIEST SN ON MON NGT...WITH ADDITIONAL HEAVY
LES IMPACTING AREAS E OF MARQUETTE LATER ON MON THRU MON NGT. LATER
SHIFTS NO DOUBT WL NEED TO HOIST LES HEADLINES. THE STRONG NW WINDS
MAY ALSO CAUSE HI ENOUGH WAVES ON LK SUPERIOR TO BRING SOME MINOR
BEACH EROSION/FLOODING IN AREAS MOST EXPOSED TO THE HIER WINDS/WAVES
BEGINNING ON LATE MON. FOR NOW...WL CONTINUE TO MENTION THE SGFNT
LES POTENTIAL/BLSN AND HI WAVES IN THE HWO PRODUCT AND EHWO GRAPHICS.
TUE/TUE NGT...AS THE CLOSED LO SHIFTS INTO QUEBEC AND 12HR H5 HGT
RISES APRCH 100M ON TUE IN THE LARGER SCALE DNVA AHEAD OF TRAILING
H5 RDG AXIS...MID LVL SUBSIDENCE/DRYING/TREND TOWARD NEUTRAL OR MORE
ACYC LLVL FLOW WL TEND TO WEAKEN THE LES W TO E. STEADILY BACKING
WINDS OVER THE W THRU THE DAY AND MAINLY DURING TUE AFTN OVER THE E
WL TEND TO LIMIT THE RESIDENCE TIME OF THE HEAVIER SN BANDS AND
SHIFT THE LES TO PRIMARILY OVER THE KEWEENAW AND TO THE E OF
MUNISING BY LATE IN THE DAY. DESPITE THIS DIMINISHING TREND...SN
TOTALS ON MON THRU TUE WL LIKELY APRCH OR EXCEED A FOOT IN THE
FAVORED SN BELTS OVER THE W CENTERED IN ONTONAGON COUNTY AND E OF
MUNISING. AS THE FLOW CONTINUES TO BACK TOWARD THE SW ON TUE NGT IN
ADVANCE OF NEXT CLIPPER SHRTWV DIGGING SEWD TOWARD MN...THE MAIN
AREA OF LES SHOULD SHIFT INTO LK SUP. BUT MORE WIDESPREAD SN MAY
ARRIVE LATE AT NGT AT LEAST OVER THE W WITH THE ONSET OF MORE
VIGOROUS DYNAMIC FORCING/HGT FALLS IN THE DPVA AHEAD OF THE NEXT
SHRTWV.
WED THRU FRI...PASSAGE OF POTENT SHRTWV/VIGOROUS DYNAMIC FORCING WL
BRING THE THREAT OF A MORE WIDESPREAD SN AGAIN ON WED DESPITE RATHER
LIMITED ABSOLUTE MSTR /FCST PWAT UNDER 0.25 INCH/. MORE LES WL BE
THE RULE ON THU INTO FRI MAINLY IN THE NW WIND SN BELTS AS ANOTHER
COLD SHOT WITH H85 TEMPS AS LO AS -16 TO -18C POURS INTO THE UPR LKS
BEHIND THE DEPARTING SHRTWV. LONGER RANGE MODELS CONTINUE TO POINT
TOWARD SOME MODERATION IN THE COLD NEXT WEEKEND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1153 PM EST FRI NOV 14 2014
WESTERLY WINDS ACROSS LAKE SUPERIOR AND SUFFICIENTLY COLD AIR WILL
SUPPORT BKN-OVC MVFR CIGS AT KCMX THRU THE FCST PERIOD. OCNL
FLURRIES/-SHSN ARE EXPECTED AS WELL. AT KIWD/KSAW...VFR CONDITIONS
WILL PREVAIL THRU THE FCST PERIOD UNDER A RELATIVELY DRY AIR MASS.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 409 AM EST SAT NOV 15 2014
UNDER A SHARP PRES GRADIENT BETWEEN HI PRES IN THE OH RIVER VALLEY
AND LO PRES OVER HUDSON BAY...PLAN ON W WINDS UP TO 20-30KTS INTO
SUN. THE WINDS WL THEN BACK TOWARD THE SW AND DIMINISH TO UP TO
25KTS IN ADVANCE OF ANOTHER STRONG DISTURBANCE MOVING THRU SCENTRAL
CANADA AND INTO NORTHERN LAKE SUPERIOR ON MON MORNING. FOLLOWING THE
PASSAGE OF THIS LO TO THE E...THE PRES GRADIENT WILL TIGHTEN AND THE
INSTABILITY WILL INCREASE AS ANOTHER SURGE OF COLD AIR FLOWS OVER
THE RELATIVELY WARM LAKE WATERS. THE RESULT WILL BE A PERIOD OF NW
GALES ON MON INTO TUE. SINCE THIS AIRMASS WILL BE SUFFICIENTLY
COLD...THERE WILL LIKELY BE SOME FREEZING SPRAY IN SOME AREAS. THE
BEST CHANCE FOR THE GALES WILL BE OVER CENTRAL LAKE SUPERIOR. AS THE
LO PRES MOVES AWAY ON TUE AND HI PRES SHIFTS E...EXPECT THE WINDS TO
BACK TO THE W AND DIMINISH TO 25 TO 30KTS. THE PASSAGE OF ANOTHER
STRONG DISTURBANCE ON WED MAY LEAD TO ANOTHER NW GALE EVENT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...KC
AVIATION...ROLFSON
MARINE...KC
AREA FORECAST DISCUSSION
NWS RALEIGH NC
240 AM EST SAT NOV 15 2014
.SYNOPSIS...HIGH PRESSURE WILL SETTLE OVER THE REGION ON SATURDAY...
THEN SHIFT OFFSHORE SUNDAY AND SUNDAY NIGHT AS A COLD FRONT
APPROACHES THE MOUNTAINS FROM THE WEST. A COLD FRONT WILL SURGE
EASTWARD THROUGH THE CAROLINAS MONDAY EVENING.
&&
.NEAR TERM /THROUGH SUNDAY/...
AS OF 230 AM SATURDAY...
TODAY AND TONIGHT: SURFACE HIGH PRESSURE WILL CENTER OVER NORTH
CAROLINA AND VIRGINIA ON SATURDAY AS MID-LEVEL FLOW BECOMES ZONAL OR
SLIGHTLY SOUTHWESTERLY. THAT MEANS THICKNESS VALUES WILL BEGIN TO
RISE AND TEMPERATURES WILL BOTTOM OUT WITH THE MINIMUMS SATURDAY
MORNING...IN THE LOW TO MID 20S. WITH NO DISTURBANCES IN THE UPPER
LEVEL VORTICITY FIELD AND HIGH PRESSURE IN CONTROL...SATURDAY SHOULD
BE A MOSTLY CLEAR DAY WITH MINIMAL WIND. THIS WILL GIVE CONDITIONS
FOR INSOLATION BUT WITH THE COLD AIRMASS IN PLACE AND THICKNESS
VALUES ONLY JUST APPROACHING 1300 N BY THE SATURDAY AFTERNOON...ONLY
EXPECT HIGHS TO TOP OUT IN THE MID 40S ACROSS THE AREA. SLIGHT WARM
AIR ADVECTION WILL MODERATE THICKNESS SATURDAY NIGHT BY TEN METERS
OR SO...DRIVING A 3-5 DEGREE IMPROVEMENT IN LOW TEMPERATURES SUNDAY
MORNING.
SUNDAY: HIGH PRESSURE BEGINS TO SHIFT EASTWARD AND CENTRAL NC WILL
BEGIN TO FEEL SOME RETURN FLOW. THIS WILL HELP MODERATE TEMPERATURES
ON SUNDAY INTO THE LOWER 50S...STILL ABOUT 10 DEGREES BELOW NORMAL
FOR THIS TIME OF YEAR. A VORTICITY MAXIMUM WILL APPROACH FROM THE
SOUTH WHICH WILL CAUSE THE AREA TO OVERSPREAD WITH SOME 850 MB
CLOUDINESS BY SUNDAY AFTERNOON. MOST OF THE AREA SHOULD REMAIN DRY
HOWEVER AS PRECIPIATION ASSOCIATED WITH THE DEVELOPING TROUGH
REMAINS TO THE SOUTHEAST AND THE APPROACHING FRONTAL SYSTEM REMAINS
WEST OF THE AREA...DRAPED ACROSS THE DEEP SOUTH. THE CAVEAT TO THIS
IS THAT THE POSITION OF THE SURFACE HIGH AND NEWLY FORMING TROUGH
WILL HELP SET UP AN IN-SITU DAMMING SITUATION WITH A COASTAL FRONT
THAT COULD PROVIDE THE MOISTURE FOR SOME LIGHT OVERRUNNING
PRECIPITATION DRIVEN BY ISENTROPIC LIFT.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH MONDAY NIGHT/...
AS OF 235 AM SATURDAY...
SUNDAY NIGHT: HOW LONG THE IN-SITU DAMMING SITUATION HANGS AROUND
REMAINS TO BE SEEN AS THE VERY DEEP UPPER LEVEL TROUGH OVER THE
CENTRAL CONUS IS QUITE AGGRESSIVE WITH FORCING THE FRONTAL SYSTEM
OVER THE APPALACHIANS INTO THE AREA AND BLOWING OUT THE WEDGE FRONT.
WHETHER OR NOT THE DAMMING STICKS AROUND OR THE FRONT APPROACHES
FROM THE WEST...THE UPSHOT WILL BE THE SAME...AN INCREASE IN POPS
FOR SUNDAY NIGHT INTO EARLY MONDAY MORNING WITH THE GREATEST CHANCES
IN THE NORTHWEST BUT QPF VALUES REMAINING UNDER A QUARTER OF AN INCH
THROUGH 12Z MONDAY. INCREASED WARM AIR ADVECTION WILL HELP THICKNESS
VALUES REACH 1350 M BY DAYBREAK ON MONDAY AND THUS LOWS WILL
MODERATE SIGNIFICANTLY..INTO THE LOW TO MID 40S. -ELLIS
FOR MON/MON NIGHT: MONDAY WILL START WITH THE WARM FRONT SW-TO-NE
THROUGH CENTRAL NC MOVING TO THE NW... AS THE STRONG COLD FRONT
APPROACHES FROM THE EAST. RAIN IS EXPECTED TO CONTINUE INTO
MONDAY... WITH HIGHEST POPS IN THE NW HALF OF CENTRAL NC IN THE
MORNING... SPREADING EAST THROUGH THE AFTERNOON. STRONG LOW LEVEL
MASS FLUX CONFLUENCE COUPLED WITH VIGOROUS UPPER DIVERGENCE WILL
CONTINUE TO FUEL WIDESPREAD PRECIP... WITH ADDITIONAL FORCING FOR
ASCENT PROVIDED BY POCKETS OF MID LEVEL VORTICITY (DIFFICULT TO
PINPOINT AT THIS RANGE) THAT WILL TRACK TO THE NE WITHIN THE FAST
MID LEVEL SWRLY FLOW... PART OF THE STRONG BROAD TROUGH COVERING
NEARLY THE ENTIRE CONUS. BASED ON THIS EXPECTED DEEP LIFT AND
ABUNDANT MOISTURE (PW VALUES OVER 1.5 INCHES NOW OVER THE SOURCE
REGION IN THE BAY OF CAMPECHE WILL SURGE NE INTO NC BY MON...
EQUATING TO PW OF 2 STANDARD DEVIATIONS ABOVE NORMAL)... WILL BUMP
UP POPS TO CATEGORICAL... MAINLY WEST HALF MON MORNING AND EXPANDING
EAST IN THE AFTERNOON BEFORE SLOWLY EXITING IN THE EVENING. THE
NAM/GFS/ECMWF ALL DIFFER SLIGHTLY WITH THE PLACEMENT AND STRENGTH OF
SURFACE LOWS TRACKING ALONG THE INCOMING COLD FRONT... WITH THE
GFS/ECMWF SHOWING STRONGER LOWS AND A SLIGHTLY FASTER FRONTAL
PASSAGE THROUGH CENTRAL NC MON AFTERNOON/EVENING AS COMPARED TO THE
NAM... BUT OVERALL TIMING IS IN FAIRLY DECENT AGREEMENT. BOTH THE
NAM AND GFS DEPICT LOW BUT NON-ZERO MUCAPE VALUES IN THE EAST MON
AFTERNOON INTO EARLY EVENING (100-250 J/KG ON THE GFS AND 250-750
J/KG ON THE NAM) WITH STRONG DEEP LAYER SHEAR OF 60-90 KTS... AND
WHILE MID LEVEL LAPSE RATES ARE JUST MARGINAL AT 5.5-6.0 C/KM... THE
MOISTURE ALOFT AND ASCENT ARE SUFFICIENT TO MENTION ISOLATED THUNDER
IN THE ERN CWA LATE MON. TEMP FORECAST FOR MON IS A CHALLENGE...
GIVEN THE HIGH POTENTIAL FOR A WEDGE REGIME TO HOLD IN THE NW
PIEDMONT DESPITE A STRONG SSW LOW LEVEL FLOW PRECEDING THE FRONT.
THE NAM REMAINS THE MOST SUPPORTIVE OF A LINGER WEDGE... IN LINE
WITH THE 12Z/14TH ECMWF... HOWEVER THE NEW ECMWF IS CLOSER TO THE
GFS WITH A STRONGER ALONG-FRONT SURFACE LOW AND RESULTING PREFRONTAL
DISSOLUTION OF THE WEDGE REGIME. WITH THE LACK OF MODEL CONSENSUS ON
THIS AND BASED ON PAST EXPERIENCE... WILL STICK WITH LINGERING
COLDER AND MORE STABLE AIR OVER THE NW MON... BUT STAY TUNED... AS
JUST A QUICK JUMP OF THE WARM FRONT MORE TO THE NW WILL YIELD MUCH
HIGHER TEMPS. WILL HAVE HIGHS RANGING FROM AROUND 50 NW TO AROUND 70
SE... WITH PERIODICALLY GUSTY SW WINDS... ALTHOUGH THE MOIST
ADIABATIC LOW LEVEL PROFILE COULD LIMIT MIXING OF THE STRONGEST
WINDS DOWN TO THE SURFACE. EXPECT THE COLD FRONT TO MOVE QUICKLY
EAST AND OFF THE COAST MON NIGHT... WITH MUCH COLDER AIR SURGING IN
FROM THE NW... AND GRADUAL CLEARING OVERNIGHT. WE`LL HANG ONTO THE
MIXED LAYER UP THROUGH ABOUT 900 MB OVERNIGHT... AND NW WINDS BEING
THE FRONT WILL BE QUITE BRISK WITH OCCASIONAL GUSTS OVER 20 MPH
POSSIBLE. THE POLAR CHARACTER OF THE INCOMING AIR MASS WITH LITTLE
IMPEDIMENT TO ITS ARRIVAL SUPPORTS LOWS JUST A TAD LOWER THAN
PREVIOUS LOWS... FROM 26 WEST TO 38 SOUTHEAST. -GIH
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 235 AM SATURDAY...
WITH THE POLAR FLOODGATES WIDE OPEN... THE COLDEST AIR OF THIS
STRETCH WILL BE UPON US TUE... MAKING THIS THE CHILLIEST DAY AS
FORECAST THICKNESSES BOTTOM OUT BELOW 1275 M OVER MOST OF CENTRAL
NC. THESE VALUES ALONG WITH FORECAST SOUNDINGS INDICATE A STRUGGLE
TO GET OUT OF THE MID 30S OVER THE NW PIEDMONT... DESPITE PLENTIFUL
SUNSHINE. HAVE TRENDED TEMPS IN THIS DIRECTION... WITH HIGHS FROM 37
NW TO 44 SE. THE TROUGH LIFTS NE AND WEAKENS A BIT WED/THU AS THE
SURFACE HIGH MODIFIES WHILE SLIDING ACROSS THE SOUTHEAST STATES.
SHOULD SEE HIGHS BACK UP INTO THE LOW-MID 40S THU AND AROUND 50-55
THU... STILL WELL BELOW NORMAL. A FEW HIGH CLOUDS ARE LIKELY TO
RETURN LATE WED INTO WED NIGHT AS WEAK VORTICITY SHEARS ACROSS NC
WITHIN THE PERSISTENT CYCLONIC FLOW. DETAILS IN THE GFS/ECMWF START
TO GET VERY MURKY LATE THU INTO FRI AS LONGWAVE TROUGHING DIGS ANEW
THROUGH THE GREAT LAKES AND POTENTIALL DOWN INTO THE CENTRAL
PLAINS... WHICH WOULD MEAN THE SURFACE HIGH WOULD MOVE OFF THE COAST
WITH RESULTANT SW RETURN FLOW PUMPING MOISTURE INTO THE CAROLINA
AHEAD OF THE NEXT FRONT. WILL BRING IN SLIGHT CHANCE POPS ACROSS THE
WEST AND NORTH... STILL BELOW CLIMATOLOGY AND IN LINE WITH THE ECMWF
WHICH SHOWS PRECIP ENTERING WRN NC FRI. HIGHS FRI IN THE MID-UPPER
50S. EXPECT LOWS TUE NIGHT/WED MORNING IN THE TEENS TO LOW 20S...
SLOWLY WARMING THROUGH THE END OF THE WEEK TO AROUND FREEZING FRI
MORNING. -GIH
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
AS OF 1235 AM SATURDAY...
24 HOUR TAF PERIOD: VERY HIGH CONFIDENCE OF VFR CONDITIONS
PERSISTING THROUGH THE TAF PERIOD AS HIGH PRESSURE BEGINS TO MOVE
OVERHEAD. THAT BEING SAID...THERE IS A THREAT TONIGHT FOR SOME LOW
LEVEL WIND SHEAR IN THE 500-1000 FT LAYER AT EASTERN SITES
(KRDU...KFAY...AND ESPECIALLY KRWI) WHERE WIND SPEEDS WILL GO FROM
RELATIVELY LIGHT AT 500 FT TO 25-30 KTS OR SO AT 1000 FT. THIS IS
BACKED UP BY WIND PROFILER DATA AT 530Z SHOWING 1 KT AT THE SURFACE
AND 33 KTS AT 900 FT. RAP FORECAST SOUNDINGS SHOW THIS ACTIVITY
CONTINUING UNTIL 13-14Z SATURDAY MORNING. OTHERWISE MOSTLY CLEAR
SKIES OVERNIGHT WITH LIGHT NORTHWESTERLY WINDS SHIFTING TO
NORTHEASTERLY DURING THE OVERNIGHT HOURS. FOR SATURDAY EXPECT WINDS
5-10 KTS OUT OF THE NORTHEAST THEN POSSIBLY SHIFTING TO A MORE
EASTERLY DIRECTION LATER IN THE AFTERNOON. BY 00Z OR SO SOME MID TO
HIGH LEVEL CLOUDS MAY START TO FILTER IN ABOVE 10 KFT.
LONG TERM: THE NEXT THREAT TO SUB-VFR CONDITIONS WILL COME ON MONDAY
AS A FRONTAL SYSTEM STARTS TO CROSS THE APPALACHIANS. HIGH PRESSURE
WILL THEN RETURN ON TUESDAY FOR THE REMAINDER OF THE WEEK.
&&
.CLIMATE...
THE FOLLOWING ARE RECORD TEMPERATURES THAT WILL BE CHALLENGED
THROUGH THE FORECAST PERIOD:
RECORD LOW:
GSO RDU FAY
SAT 11/15 - 20 IN 1969 21 IN 1969 22 IN 1942
WED 11/19 - 20 IN 1951 21 IN 1903 21 IN 1959
THU 11/20 - 12 IN 1951 19 IN 1951 20 IN 1951
RECORD LOW MAX:
GSO RDU FAY
TUE 11/18 - 37 IN 1924 35 IN 1924 46 IN 2008
WED 11/19 - 34 IN 1951 36 IN 1951 41 IN 2000
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...ELLIS
SHORT TERM...ELLIS/GIH
LONG TERM...GIH
AVIATION...ELLIS
CLIMATE...MWS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1236 AM EST SAT NOV 15 2014
.SYNOPSIS...HIGH PRESSURE WILL SETTLE OVER THE REGION ON SATURDAY...
THEN SHIFT OFFSHORE SUNDAY AND SUNDAY NIGHT AS A COLD FRONT
APPROACHES THE MOUNTAINS FROM THE WEST. THE COLD FRONT WILL SURGE
EASTWARD THROUGH THE CAROLINAS MONDAY EVENING.
&&
.NEAR TERM /TONIGHT/...
AS OF 730 PM FRIDAY...
MODIFIED ARCTIC HIGH PRESSURE BUILDING INTO THE REGION THIS EVENING
WILL SETTLE OVERHEAD TONIGHT. WITH CLEAR SKIES AND A COLD/DRY
AIRMASS IN PLACE...THE ONLY MITIGATING FACTOR W/REGARD TO THE
REALIZATION OF FULL RADIATIONAL COOLING WILL BE A LIGHT NW BREEZE
THROUGH 06-09Z. HOWEVER...PREVIOUS EXPERIENCE WOULD SUGGEST THAT
SEVERAL HRS OF CALM CONDITIONS PRIOR TO SUNRISE SHOULD BE SUFFICIENT
FOR LOWS IN THE LOW/MID 20S...PERHAPS UPPER TEENS IN A FEW
LOCATIONS WHERE WINDS REMAIN CALM FROM MIDNIGHT ONWARD. -VINCENT
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY/...
AS OF 250 PM FRIDAY...
SURFACE HIGH OVER THE FORECAST AREA WILL DRIFT EAST...THOUGH SURFACE
RIDGE AXIS WILL LINGER/EXTEND ACROSS THE REGION THROUGH EARLY
SUNDAY. WHILE THE LOWEST 10K OF THE ATMOSPHERE WILL BE TOO DRY TO
SUPPORT ANY CLOUDS...THE WLY FLOW ALOFT MAY ADVECT ENOUGH MOISTURE
TO CAUSE AREAS OF CIRRUS OVERHEAD LATE SATURDAY MORNING THROUGH
THE AFTERNOON. AT THIS TIME ANTICIPATE THE HIGH CLOUDS TO BE
THIN...SO THEY SHOULD NOT HAVE ANY IMPACTS ON TEMPS. IF CIRRUS
SHIELD THICKER/DENSER THAN CURRENTLY ANTICIPATED...THEN MAX
TEMPS MAY END UP BEING 3-4 DEGREES COOLER THAN FORECAST. THE DRY AIR
MASS WILL ALLOW TEMPS TO REBOUND FROM A FRIGID START. AFTERNOON
TEMPS SHOULD BE IN THE MID-UPPER 40S.
MODEL RH CROSS SECTIONS SUGGEST HIGH CLOUDS DEPARTING THE REGION
EARLY SATURDAY EVENING WITH MAINLY CLEAR SKIES FOR MOST OF THE NIGHT
UNTIL THE NEXT ROUND OF HIGH CLOUDS APPROACHES FROM THE WEST AROUND
DAYBREAK SUNDAY. THE MAINLY CLEAR SKIES AND CALM WINDS WILL AGAIN
ALLOW TEMPS TO FALL QUICKLY AFTER SUNSET. EXPECT MIN TEMPS SOLIDLY
IN THE MID-UPPER 20S.
SUNDAY...AS SURFACE HIGH RETREATS FARTHER AWAY FROM CENTRAL NC...THE
LOW LEVEL RETURN SLY FLOW WILL ADVECT MOISTURE OFF THE ATLANTIC INTO
THE SOUTHERN AND EASTERN SECTIONS OF CENTRAL NC. MODEL RH PLANE VIEW
PLOTS SUGGEST THE AIR MASS BETWEEN 925-850 MB ADEQUATELY MOIST TO
SUPPORT A DECK OF STRATOCU ACROSS THE SOUTHERN
PIEDMONT...SANDHILLS...AND SOUTHERN COASTAL PLAIN BY SUNDAY
AFTERNOON. OTHERWISE HIGH CLOUDS WILL THICKEN OVERHEAD ELSEWHERE IN
ADVANCE OF THE NEXT LOW PRESSURE SYSTEM. THERE MAY BE ENOUGH
ISENTROPIC UPGLIDE TO PERMIT THE DEVELOPMENT OF SPOTTY LIGHT RAIN
OVER THE FAR SOUTH-SE AND POSSIBLY THE FAR NW PRIOR TO SUNSET SUNDAY.
HIGH TEMPS SUNDAY WILL BE DICTATED TO THE EXTENT OF CLOUD COVER.
AIR MASS PROJECTED TO MODIFY WITH LOW LEVEL THICKNESSES IN THE MID
1330S. THESE VALUES STILL ABOUT 15M BELOW NORMAL...SUPPORTIVE OF MAX
TEMPS IN THE MID-UPPER 50S. SINCE EXPECTING THICKENING CLOUD
COVER...MAX TEMPS SHOULD TOP OUT IN THE LOW-MID 50S.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
AS OF 305 PM FRIDAY...
FOR THE PERIOD SUNDAY NIGHT THROUGH MONDAY...A SERIES OF MID-LEVEL
SHORTWAVES ARE FORECAST TO MOVE THROUGH CENTRAL NORTH CAROLINA WITH
THE BEST LIFT FORECAST BY BOTH THE NAM AND GFS DURING THE DAY
MONDAY. THE NAM IS DRY FOR A LARGE PART OF SUNDAY NIGHT...WHICH IS
CLOSER TO WHAT THE 12Z ECMWF IS FORECASTING...WHILE THE GFS
SATURATES THE AIR MASS MUCH MORE QUICKLY SUNDAY NIGHT. BETTER 700MB
VORTICITY IS FORECAST MONDAY BY BOTH THE NAM AND THE GFS...AND THE
GREATER 850MB THETA-E AND K INDICES OCCUR THEN ALONG WITH THE
PASSAGE OF BETTER VORTICITY ON THE 1.5PVU SURFACE AS THE RIGHT
ENTRANCE REGION OF A 100KT 500MB JET APPROACHES LATE IN THE DAY.
FOR THIS FORECAST...EVEN THE DRIER NAM PROVIDES FOR LIKELY CHANCES
FOR RAIN IN THE TRIAD BY LATE SUNDAY NIGHT AND WILL BASICALLY
FORECAST LIKELY CHANCES THERE AND TOWARD ALBEMARLE AFTER MIDNIGHT
WITH CHANCES ELSEWHERE. FOR MONDAY...POPS WILL BE LIKELY WEST OF
INTERSTATE 95 FOR MUCH OF THE DAY...WITH LIKELY POPS ALONG AND EAST
OF INTERSTATE 95 AS THE 850MB THETA-E VALUES ARE MAXIMIZED IN
CENTRAL NORTH CAROLINA DURING THE AFTERNOON. AROUND 18Z...THE GFS
FORECASTS 850MB WINDS INCREASING TO AROUND 60KT IN THE COASTAL PLAIN
COINCIDENT WITH THE INCREASE IN 850MB THETA-E.
MUCAPE FROM 1000-500MB IS ONLY 100-200J/KG IN THE INTERSTATE 95
CORRIDOR MONDAY...AND NAM AND GFS BUFR SOUNDINGS SHOW LAPSE RATES
NEAR MOIST ADIABATIC. HOWEVER...THE 0-3KM SHEAR IS AROUND 50KT...
AND 0-3KM HELICITY IS FORECAST TO INCREASE INTO TRIPLE FIGURES M2/S2
ON BUFR SOUNDINGS AT KFAY AND KRWI BY 21Z. BUFR SOUNDINGS ALSO SHOW
SOME EROSION THE CAP...AND WHILE THE WINDOW IS NARROW...LIKELY ONLY
AROUND 19Z TO 22Z OR SO...THERE IS A NON-ZERO THREAT OF STRONGER...
DEEP CONVECTION MONDAY AFTERNOON BUT FOR THIS FORECAST WILL HOLD OFF
ON THE MENTION OF THUNDER IN ORDER TO EVALUATE TRENDS. IS THE
SURFACE LOW IS DEEPER OR SURFACE DEW POINTS START TO FIND THEIR WAY
MORE INTO THE 60S IN THE FAR EAST MONDAY AFTERNOON...THE POTENTIAL
FOR LOCAL SEVERE WEATHER COULD INCREASE.
GIVEN THE DISPARITY IN THE MODEL GUIDANCE LOWS FOR SUNDAY NIGHT...
AND UNCERTAINTY IN HOW QUICKLY LOWER CLOUDS AND PRECIPITATION MAY
DEVELOP...OPTED FOR A BLEND OF MOS VALUES FOR LOWS SUNDAY NIGHT IN
THE LOWER TO MID 40S. ON MONDAY...CERTAINLY A CHALLENGE IN TERMS OF
THE HIGHS CONSIDERING ANY COLD-AIR DAMMING...AND FOR THIS FORECAST
WILL HAVE MAXES IN THE LOWER TO MID 50S IN THE IMMEDIATE TRIAD... TO
NEAR 70 TOWARD KFAY AND KCTZ. GIVEN THE INCREASE IN 850MB AND 925MB
WINDS EAST MONDAY AFTERNOON...THERE COULD BE A FEW GUSTS NEAR 30MPH
IN THE COASTAL PLAIN THEN.
FOR THE PERIOD MONDAY NIGHT THROUGH TUESDAY...WHILE THE GFS HAS BEEN
FASTER THAN THE ECMWF WITH THE PASSAGE OF THE COLD FRONT AND THE
RETURN OF MUCH COLDER AIR...EVEN THE SLOWER ECMWF WOULD SUGGEST THE
COLD AIR CHASING THE MOISTURE MONDAY NIGHT SUCH THAT DRYING SHOULD
OCCUR BEFORE PARTIAL THICKNESSES AND SURFACE WET BULB TEMPERATURES
FALL TO RESULT IN ANY NON-LIQUID PRECIPITATION LATE MONDAY NIGHT.
ANTICIPATING THE CHANCES FOR PRECIPITATION FALLING BELOW SLIGHT BY
12Z TUESDAY...CHANCE-TO-LIKELY POPS WEST TO EAST MONDAY EVENING
DIMINISH OVERNIGHT WITH DRYING BEHIND THE COLD FRONT. IF THERE WOULD
BE ANY NON-LIQUID PRECIPITATION...THE THOUGHT WOULD BE IT WOULD
OCCUR EAST OF U.S. 1 IMMEDIATELY AT THE END OF THE PRECIPITATION AND
HAVE NO IMPACT.
FROM THERE...COLD HIGH PRESSURE BUILDS INTO CENTRAL NORTH CAROLINA
WITH 1000-850MB THICKNESSES POSSIBLE FALLING INTO THE 1250S TUESDAY
NIGHT WHICH BY LOCAL STUDY RESULTS IN LOWS WELL INTO THE 20S AND
POSSIBLY INTO THE TEENS. FORECASTS OF MOISTURE ALOFT...WHICH
SOMETIMES RESULTS IN CHALLENGES FOR VERY COLD OVERNIGHT LOWS...ARE
DRY...WITH THE HIGH BUILDING IN MAKING FOR LIGHT WINDS AS WELL.
AFTER HIGHS ON TUESDAY THAT MAY CHALLENGE THE RECORD LOW MAXIMUM
TEMPERATURE AT KFAY DEPENDING ON THE MIDNIGHT TEMPERATURE EARLY
TUESDAY...OVERNIGHT LOWS TUESDAY NIGHT SHOULD BE CLOSE TO RECORDS AT
LEAST AT KGSO AND KRDU. THE DAYTIME HIGH WEDNESDAY AT KFAY WILL...
AGAIN...LIKELY BE CLOSE TO THE RECORD LOW MAXIMUM THERE BASED ON THE
EXPECTED HIGH TEMPERATURE FORECAST FROM THE 1000-850MB THICKNESSES.
WHILE HIGH PRESSURE WILL BE IN PLACE AT THE SURFACE...A MODEST MID-
LEVEL SHORTWAVE MOVING THROUGH OR NEAR CENTRAL NORTH CAROLINA LATE
WEDNESDAY COULD RESULT IN THE PASSAGE OF SOME MID- OR HIGH-LEVEL
CLOUDS THEN.
GRADUAL WARMING SHOULD TAKE PLACE DURING THE END OF THE WEEK AS THE
COLD...UPPER TROUGH STARTS TO RETREAT. OVERNIGHT LOWS THURSDAY NIGHT
ARE COMPLICATED BY THE POTENTIAL FOR SOME HIGH CLOUDS AS THE UPPER
FLOW BACKS. BY FRIDAY...A SURFACE FRONT SHOULD BE MOVING TOWARD THE
VIRGINIA BORDER FROM THE NORTH...AND WHILE HIGH PRESSURE OVER THE
GULF SHOULD LIMIT THE LOW-LEVEL MOISTURE RETURN TOWARD CENTRAL NORTH
CAROLINA...BY OVERNIGHT FRIDAY THERE IS WHAT WILL CURRENTLY BE
FORECAST AS A SLIGHT CHANCE OF RAIN MAINLY IN THE INTERSTATE 85
CORRIDOR. PARTIAL THICKNESSES ARE WELL TOO WARM FOR ANYTHING BUT
LIQUID...BUT NOT CONFIDENT ENOUGH IN THE MOISTURE RETURN OR FRONTAL
CONVERGENCE TO FORECAST POPS BEYOND SLIGHT AT THIS POINT. BY
FRIDAY...TEMPERATURES SHOULD FINALLY RETURN CLOSE TO NORMAL.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
AS OF 1235 AM SATURDAY...
24 HOUR TAF PERIOD: VERY HIGH CONFIDENCE OF VFR CONDITIONS
PERSISTING THROUGH THE TAF PERIOD AS HIGH PRESSURE BEGINS TO MOVE
OVERHEAD. THAT BEING SAID...THERE IS A THREAT TONIGHT FOR SOME LOW
LEVEL WIND SHEAR IN THE 500-1000 FT LAYER AT EASTERN SITES
(KRDU...KFAY...AND ESPECIALLY KRWI) WHERE WIND SPEEDS WILL GO FROM
RELATIVELY LIGHT AT 500 FT TO 25-30 KTS OR SO AT 1000 FT. THIS IS
BACKED UP BY WIND PROFILER DATA AT 530Z SHOWING 1 KT AT THE SURFACE
AND 33 KTS AT 900 FT. RAP FORECAST SOUNDINGS SHOW THIS ACTIVITY
CONTINUING UNTIL 13-14Z SATURDAY MORNING. OTHERWISE MOSTLY CLEAR
SKIES OVERNIGHT WITH LIGHT NORTHWESTERLY WINDS SHIFTING TO
NORTHEASTERLY DURING THE OVERNIGHT HOURS. FOR SATURDAY EXPECT WINDS
5-10 KTS OUT OF THE NORTHEAST THEN POSSIBLY SHIFTING TO A MORE
EASTERLY DIRECTION LATER IN THE AFTERNOON. BY 00Z OR SO SOME MID TO
HIGH LEVEL CLOUDS MAY START TO FILTER IN ABOVE 10 KFT.
LONG TERM: THE NEXT THREAT TO SUB-VFR CONDITIONS WILL COME ON MONDAY
AS A FRONTAL SYSTEM STARTS TO CROSS THE APPALACHIANS. HIGH PRESSURE
WILL THEN RETURN ON TUESDAY FOR THE REMAINDER OF THE WEEK.
&&
.CLIMATE...
THE FOLLOWING ARE RECORD TEMPERATURES THAT WILL BE CHALLENGED
THROUGH THE FORECAST PERIOD:
RECORD LOW:
GSO RDU FAY
SAT 11/15 - 20 IN 1969 21 IN 1969 22 IN 1942
WED 11/19 - 20 IN 1951 21 IN 1903 21 IN 1959
THU 11/20 - 12 IN 1951 19 IN 1951 20 IN 1951
RECORD LOW MAX:
GSO RDU FAY
TUE 11/18 - 37 IN 1924 35 IN 1924 46 IN 2008
WED 11/19 - 34 IN 1951 36 IN 1951 41 IN 2000
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...VINCENT
SHORT TERM...WSS
LONG TERM...DJF
AVIATION...ELLIS
CLIMATE...MWS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1236 PM EST FRI NOV 14 2014
.SYNOPSIS...HIGH PRESSURE WILL SETTLE OVER THE REGION ON SATURDAY...
THEN SHIFT OFFSHORE SUNDAY AND SUNDAY NIGHT AS A COLD FRONT
APPROACHES THE MOUNTAINS FROM THE WEST. THE COLD FRONT WILL SURGE
EASTWARD THROUGH THE CAROLINAS MONDAY EVENING.
&&
.NEAR TERM /TONIGHT/...
AS OF 730 PM FRIDAY...
MODIFIED ARCTIC HIGH PRESSURE BUILDING INTO THE REGION THIS EVENING
WILL SETTLE OVERHEAD TONIGHT. WITH CLEAR SKIES AND A COLD/DRY
AIRMASS IN PLACE...THE ONLY MITIGATING FACTOR W/REGARD TO THE
REALIZATION OF FULL RADIATIONAL COOLING WILL BE A LIGHT NW BREEZE
THROUGH 06-09Z. HOWEVER...PREVIOUS EXPERIENCE WOULD SUGGEST THAT
SEVERAL HRS OF CALM CONDITIONS PRIOR TO SUNRISE SHOULD BE SUFFICIENT
FOR LOWS IN THE LOW/MID 20S...PERHAPS UPPER TEENS IN A FEW
LOCATIONS WHERE WINDS REMAIN CALM FROM MIDNIGHT ONWARD. -VINCENT
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY/...
AS OF 250 PM FRIDAY...
SURFACE HIGH OVER THE FORECAST AREA WILL DRIFT EAST...THOUGH SURFACE
RIDGE AXIS WILL LINGER/EXTEND ACROSS THE REGION THROUGH EARLY
SUNDAY. WHILE THE LOWEST 10K OF THE ATMOSPHERE WILL BE TOO DRY TO
SUPPORT ANY CLOUDS...THE WLY FLOW ALOFT MAY ADVECT ENOUGH MOISTURE
TO CAUSE AREAS OF CIRRUS OVERHEAD LATE SATURDAY MORNING THROUGH
THE AFTERNOON. AT THIS TIME ANTICIPATE THE HIGH CLOUDS TO BE
THIN...SO THEY SHOULD NOT HAVE ANY IMPACTS ON TEMPS. IF CIRRUS
SHIELD THICKER/DENSER THAN CURRENTLY ANTICIPATED...THEN MAX
TEMPS MAY END UP BEING 3-4 DEGREES COOLER THAN FORECAST. THE DRY AIR
MASS WILL ALLOW TEMPS TO REBOUND FROM A FRIGID START. AFTERNOON
TEMPS SHOULD BE IN THE MID-UPPER 40S.
MODEL RH CROSS SECTIONS SUGGEST HIGH CLOUDS DEPARTING THE REGION
EARLY SATURDAY EVENING WITH MAINLY CLEAR SKIES FOR MOST OF THE NIGHT
UNTIL THE NEXT ROUND OF HIGH CLOUDS APPROACHES FROM THE WEST AROUND
DAYBREAK SUNDAY. THE MAINLY CLEAR SKIES AND CALM WINDS WILL AGAIN
ALLOW TEMPS TO FALL QUICKLY AFTER SUNSET. EXPECT MIN TEMPS SOLIDLY
IN THE MID-UPPER 20S.
SUNDAY...AS SURFACE HIGH RETREATS FARTHER AWAY FROM CENTRAL NC...THE
LOW LEVEL RETURN SLY FLOW WILL ADVECT MOISTURE OFF THE ATLANTIC INTO
THE SOUTHERN AND EASTERN SECTIONS OF CENTRAL NC. MODEL RH PLANE VIEW
PLOTS SUGGEST THE AIR MASS BETWEEN 925-850 MB ADEQUATELY MOIST TO
SUPPORT A DECK OF STRATOCU ACROSS THE SOUTHERN
PIEDMONT...SANDHILLS...AND SOUTHERN COASTAL PLAIN BY SUNDAY
AFTERNOON. OTHERWISE HIGH CLOUDS WILL THICKEN OVERHEAD ELSEWHERE IN
ADVANCE OF THE NEXT LOW PRESSURE SYSTEM. THERE MAY BE ENOUGH
ISENTROPIC UPGLIDE TO PERMIT THE DEVELOPMENT OF SPOTTY LIGHT RAIN
OVER THE FAR SOUTH-SE AND POSSIBLY THE FAR NW PRIOR TO SUNSET SUNDAY.
HIGH TEMPS SUNDAY WILL BE DICTATED TO THE EXTENT OF CLOUD COVER.
AIR MASS PROJECTED TO MODIFY WITH LOW LEVEL THICKNESSES IN THE MID
1330S. THESE VALUES STILL ABOUT 15M BELOW NORMAL...SUPPORTIVE OF MAX
TEMPS IN THE MID-UPPER 50S. SINCE EXPECTING THICKENING CLOUD
COVER...MAX TEMPS SHOULD TOP OUT IN THE LOW-MID 50S.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
AS OF 305 PM FRIDAY...
FOR THE PERIOD SUNDAY NIGHT THROUGH MONDAY...A SERIES OF MID-LEVEL
SHORTWAVES ARE FORECAST TO MOVE THROUGH CENTRAL NORTH CAROLINA WITH
THE BEST LIFT FORECAST BY BOTH THE NAM AND GFS DURING THE DAY
MONDAY. THE NAM IS DRY FOR A LARGE PART OF SUNDAY NIGHT...WHICH IS
CLOSER TO WHAT THE 12Z ECMWF IS FORECASTING...WHILE THE GFS
SATURATES THE AIR MASS MUCH MORE QUICKLY SUNDAY NIGHT. BETTER 700MB
VORTICITY IS FORECAST MONDAY BY BOTH THE NAM AND THE GFS...AND THE
GREATER 850MB THETA-E AND K INDICES OCCUR THEN ALONG WITH THE
PASSAGE OF BETTER VORTICITY ON THE 1.5PVU SURFACE AS THE RIGHT
ENTRANCE REGION OF A 100KT 500MB JET APPROACHES LATE IN THE DAY.
FOR THIS FORECAST...EVEN THE DRIER NAM PROVIDES FOR LIKELY CHANCES
FOR RAIN IN THE TRIAD BY LATE SUNDAY NIGHT AND WILL BASICALLY
FORECAST LIKELY CHANCES THERE AND TOWARD ALBEMARLE AFTER MIDNIGHT
WITH CHANCES ELSEWHERE. FOR MONDAY...POPS WILL BE LIKELY WEST OF
INTERSTATE 95 FOR MUCH OF THE DAY...WITH LIKELY POPS ALONG AND EAST
OF INTERSTATE 95 AS THE 850MB THETA-E VALUES ARE MAXIMIZED IN
CENTRAL NORTH CAROLINA DURING THE AFTERNOON. AROUND 18Z...THE GFS
FORECASTS 850MB WINDS INCREASING TO AROUND 60KT IN THE COASTAL PLAIN
COINCIDENT WITH THE INCREASE IN 850MB THETA-E.
MUCAPE FROM 1000-500MB IS ONLY 100-200J/KG IN THE INTERSTATE 95
CORRIDOR MONDAY...AND NAM AND GFS BUFR SOUNDINGS SHOW LAPSE RATES
NEAR MOIST ADIABATIC. HOWEVER...THE 0-3KM SHEAR IS AROUND 50KT...
AND 0-3KM HELICITY IS FORECAST TO INCREASE INTO TRIPLE FIGURES M2/S2
ON BUFR SOUNDINGS AT KFAY AND KRWI BY 21Z. BUFR SOUNDINGS ALSO SHOW
SOME EROSION THE CAP...AND WHILE THE WINDOW IS NARROW...LIKELY ONLY
AROUND 19Z TO 22Z OR SO...THERE IS A NON-ZERO THREAT OF STRONGER...
DEEP CONVECTION MONDAY AFTERNOON BUT FOR THIS FORECAST WILL HOLD OFF
ON THE MENTION OF THUNDER IN ORDER TO EVALUATE TRENDS. IS THE
SURFACE LOW IS DEEPER OR SURFACE DEW POINTS START TO FIND THEIR WAY
MORE INTO THE 60S IN THE FAR EAST MONDAY AFTERNOON...THE POTENTIAL
FOR LOCAL SEVERE WEATHER COULD INCREASE.
GIVEN THE DISPARITY IN THE MODEL GUIDANCE LOWS FOR SUNDAY NIGHT...
AND UNCERTAINTY IN HOW QUICKLY LOWER CLOUDS AND PRECIPITATION MAY
DEVELOP...OPTED FOR A BLEND OF MOS VALUES FOR LOWS SUNDAY NIGHT IN
THE LOWER TO MID 40S. ON MONDAY...CERTAINLY A CHALLENGE IN TERMS OF
THE HIGHS CONSIDERING ANY COLD-AIR DAMMING...AND FOR THIS FORECAST
WILL HAVE MAXES IN THE LOWER TO MID 50S IN THE IMMEDIATE TRIAD... TO
NEAR 70 TOWARD KFAY AND KCTZ. GIVEN THE INCREASE IN 850MB AND 925MB
WINDS EAST MONDAY AFTERNOON...THERE COULD BE A FEW GUSTS NEAR 30MPH
IN THE COASTAL PLAIN THEN.
FOR THE PERIOD MONDAY NIGHT THROUGH TUESDAY...WHILE THE GFS HAS BEEN
FASTER THAN THE ECMWF WITH THE PASSAGE OF THE COLD FRONT AND THE
RETURN OF MUCH COLDER AIR...EVEN THE SLOWER ECMWF WOULD SUGGEST THE
COLD AIR CHASING THE MOISTURE MONDAY NIGHT SUCH THAT DRYING SHOULD
OCCUR BEFORE PARTIAL THICKNESSES AND SURFACE WET BULB TEMPERATURES
FALL TO RESULT IN ANY NON-LIQUID PRECIPITATION LATE MONDAY NIGHT.
ANTICIPATING THE CHANCES FOR PRECIPITATION FALLING BELOW SLIGHT BY
12Z TUESDAY...CHANCE-TO-LIKELY POPS WEST TO EAST MONDAY EVENING
DIMINISH OVERNIGHT WITH DRYING BEHIND THE COLD FRONT. IF THERE WOULD
BE ANY NON-LIQUID PRECIPITATION...THE THOUGHT WOULD BE IT WOULD
OCCUR EAST OF U.S. 1 IMMEDIATELY AT THE END OF THE PRECIPITATION AND
HAVE NO IMPACT.
FROM THERE...COLD HIGH PRESSURE BUILDS INTO CENTRAL NORTH CAROLINA
WITH 1000-850MB THICKNESSES POSSIBLE FALLING INTO THE 1250S TUESDAY
NIGHT WHICH BY LOCAL STUDY RESULTS IN LOWS WELL INTO THE 20S AND
POSSIBLY INTO THE TEENS. FORECASTS OF MOISTURE ALOFT...WHICH
SOMETIMES RESULTS IN CHALLENGES FOR VERY COLD OVERNIGHT LOWS...ARE
DRY...WITH THE HIGH BUILDING IN MAKING FOR LIGHT WINDS AS WELL.
AFTER HIGHS ON TUESDAY THAT MAY CHALLENGE THE RECORD LOW MAXIMUM
TEMPERATURE AT KFAY DEPENDING ON THE MIDNIGHT TEMPERATURE EARLY
TUESDAY...OVERNIGHT LOWS TUESDAY NIGHT SHOULD BE CLOSE TO RECORDS AT
LEAST AT KGSO AND KRDU. THE DAYTIME HIGH WEDNESDAY AT KFAY WILL...
AGAIN...LIKELY BE CLOSE TO THE RECORD LOW MAXIMUM THERE BASED ON THE
EXPECTED HIGH TEMPERATURE FORECAST FROM THE 1000-850MB THICKNESSES.
WHILE HIGH PRESSURE WILL BE IN PLACE AT THE SURFACE...A MODEST MID-
LEVEL SHORTWAVE MOVING THROUGH OR NEAR CENTRAL NORTH CAROLINA LATE
WEDNESDAY COULD RESULT IN THE PASSAGE OF SOME MID- OR HIGH-LEVEL
CLOUDS THEN.
GRADUAL WARMING SHOULD TAKE PLACE DURING THE END OF THE WEEK AS THE
COLD...UPPER TROUGH STARTS TO RETREAT. OVERNIGHT LOWS THURSDAY NIGHT
ARE COMPLICATED BY THE POTENTIAL FOR SOME HIGH CLOUDS AS THE UPPER
FLOW BACKS. BY FRIDAY...A SURFACE FRONT SHOULD BE MOVING TOWARD THE
VIRGINIA BORDER FROM THE NORTH...AND WHILE HIGH PRESSURE OVER THE
GULF SHOULD LIMIT THE LOW-LEVEL MOISTURE RETURN TOWARD CENTRAL NORTH
CAROLINA...BY OVERNIGHT FRIDAY THERE IS WHAT WILL CURRENTLY BE
FORECAST AS A SLIGHT CHANCE OF RAIN MAINLY IN THE INTERSTATE 85
CORRIDOR. PARTIAL THICKNESSES ARE WELL TOO WARM FOR ANYTHING BUT
LIQUID...BUT NOT CONFIDENT ENOUGH IN THE MOISTURE RETURN OR FRONTAL
CONVERGENCE TO FORECAST POPS BEYOND SLIGHT AT THIS POINT. BY
FRIDAY...TEMPERATURES SHOULD FINALLY RETURN CLOSE TO NORMAL.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
AS OF 1235 AM SATURDAY...
24 HOUR TAF PERIOD: VERY HIGH CONFIDENCE OF VFR CONDITIONS
PERSISTING THROUGH THE TAF PERIOD AS HIGH PRESSURE BEGINS TO MOVE
OVERHEAD. THAT BEING SAID...THERE IS A THREAT TONIGHT FOR SOME LOW
LEVEL WIND SHEAR IN THE 500-1000 FT LAYER AT EASTERN SITES
(KRDU...KFAY...AND ESPECIALLY KRWI) WHERE WIND SPEEDS WILL GO FROM
RELATIVELY LIGHT AT 500 FT TO 25-30 KTS OR SO AT 1000 FT. THIS IS
BACKED UP BY WIND PROFILER DATA AT 530Z SHOWING 1 KT AT THE SURFACE
AND 33 KTS AT 900 FT. RAP FORECAST SOUNDINGS SHOW THIS ACTIVITY
CONTINUING UNTIL 13-14Z SATURDAY MORNING. OTHERWISE MOSTLY CLEAR
SKIES OVERNIGHT WITH LIGHT NORTHWESTERLY WINDS SHIFTING TO
NORTHEASTERLY DURING THE OVERNIGHT HOURS. FOR SATURDAY EXPECT WINDS
5-10 KTS OUT OF THE NORTHEAST THEN POSSIBLY SHIFTING TO A MORE
EASTERLY DIRECTION LATER IN THE AFTERNOON. BY 00Z OR SO SOME MID TO
HIGH LEVEL CLOUDS MAY START TO FILTER IN ABOVE 10 KFT.
LONG TERM: THE NEXT THREAT TO SUB-VFR CONDITIONS WILL COME ON MONDAY
AS A FRONTAL SYSTEM STARTS TO CROSS THE APPALACHIANS. HIGH PRESSURE
WILL THEN RETURN ON TUESDAY FOR THE REMAINDER OF THE WEEK.
&&
.CLIMATE...
THE FOLLOWING ARE RECORD TEMPERATURES THAT WILL BE CHALLENGED
THROUGH THE FORECAST PERIOD:
RECORD LOW:
GSO RDU FAY
SAT 11/15 - 20 IN 1969 21 IN 1969 22 IN 1942
WED 11/19 - 20 IN 1951 21 IN 1903 21 IN 1959
THU 11/20 - 12 IN 1951 19 IN 1951 20 IN 1951
RECORD LOW MAX:
GSO RDU FAY
TUE 11/18 - 37 IN 1924 35 IN 1924 46 IN 2008
WED 11/19 - 34 IN 1951 36 IN 1951 41 IN 2000
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...VINCENT
SHORT TERM...WSS
LONG TERM...DJF
AVIATION...ELLIS
CLIMATE...MWS
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
346 AM EST SAT NOV 15 2014
.SYNOPSIS...
HIGH PRESSURE LINGERS TODAY. NEXT SYSTEM WITH DEEPER MOISTURE
SUNDAY NIGHT INTO MONDAY. REINFORCING COLD AIR ARRIVES MONDAY
NIGHT INTO TUESDAY. COLDEST DAY TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
STRATUS HANGING TOUGH OVER THE N MOUNTAINS ATTM WHICH IS KEEPING
TEMPS UP AT EKN COMPARED A HAIR. EXPECT THESE CLOUDS TO DISSIPATE
PER HRRR OVER THE NEXT SEVERAL HRS. ELSEWHERE...QUITE COLD WITH
TEMPS RUNNING A BIT BLOW FCST CURVE IN THE OUTLYING AREAS.
ADJUSTED HOURLY TEMPS AND MINT GRID DOWN A FEW
DEGREES...ESPECIALLY AWAY FROM URBAN CENTERS. MID TEENS LOOK LIKE
A GOOD BET ACROSS THESE LOCATIONS ACROSS THE LOWLANDS. IF THE
CLOUDS OVER THE MOUNTAINS CAN CLEAR IN TIME...THEN SOME HIGH
SINGLE NUMBERS ARE POSSIBLE OVER THE HIGH RIDGES. SNOWSHOE
CURRENTLY SITTING AT 11F.
AS FOR TODAY...THE SUN WILL FINALLY MAKE AN APPEARANCE...ALBEIT
WITH A SHORT STAY. SOME CIRRUS WILL STREAK IN DURING THE FIRST
HALF OF TODAY...FOLLOWED BY INCREASE IN MID LEVEL CLOUDS
ASSOCIATED WAA ALOFT LATE IN THE AFTERNOON AND EARLY EVENING /FROM
SW TO NE/. H85 TEMPS WILL MODERATE BY ALMOST 10 DEGREES TODAY.
STILL...WITH H925 TEMPS STILL ON THE COOL SIDE...FELT ROLLING WITH
COOLER GUIDANCE /A LA LOCAL IN HOUSE MOS/ WAS THE BEST OPTION. AS
SUCH...HAVE SOME MID 30S FOR THE LOWLANDS WITH LOWER 30S FOR THE
HIGH TERRAIN. BIGGEST IMPROVEMENT IN TEMPS COMPARED TO YESTERDAY
WILL BE FELT IN THE HIGHER ELEVATIONS WHERE SNOWSHOE SHOULD MAKE A
RUN TOWARD UPPER 20S LATE IN THE DAY VERSUS LOW TEENS OBSERVED YESTERDAY.
A MID LEVEL DISTURBANCE WILL RACE THROUGH THE REGION TONIGHT.
HOWEVER...WITH LITTLE FANFARE OTHER THAN THE INCREASE IN MIDDLE
LEVEL CLOUDS. THE WAA ALOFT CONTINUES THOUGH...SO HAVE HIGHEST
RIDGES HOLDING NEAR STEADY IF NOT RISING TOWARD MORNING WITH
GENERALLY MID 20S IN THE LOWLANDS.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY NIGHT/...
A WAVE MOVING ACROSS SATURDAY NIGHT INTO SUNDAY SUFFERS FROM LACK OF
LOW LEVEL MOISTURE. SHOULD SEE LOTS OF VIRGA...BUT QUESTIONABLE HOW
MUCH MAKES IT TO THE GROUND. WILL KEEP POPS IN THE SLIGHT
CHANCE/CHANCE CATEGORIES...SLOWING INCREASING AS THE COLUMN TRIES TO
SATURATE.
MAIN SYSTEM OF INTEREST ARRIVES SUNDAY NIGHT AND CONTINUES INTO
MONDAY. SREF/NAM/ECMWF ARE THE WARMEST OF THE MODELS...WITH THE GFS
AND CANADIAN ON THE COOLER SIDE. WILL RUN IN BETWEEN THE 2 CAMPS FOR
NOW...KEEPING A BAND OF PRECIPITATION IN THE MIDDLE THAT COULD BE
EITHER RAIN OR SNOW. THIS BASICALLY KEEPS MOST OF WV AND VA AS
RAIN...WITH A TRANSITION ZONE ACROSS NORTHEAST KY/SOUTHEAST OH AND
FAR NW WV. CENTRAL OH HAS THE BEST CHANCE OF BEING ALL SNOW.
THE TIMING OF THE TRANSITION TO SNOW IS ALSO UP FOR DEBATE ON MONDAY
WITH TIMING DIFFERENCES BETWEEN THE MODELS. WILL GO BELOW MOS
GUIDANCE OF HIGHS ON MONDAY DUE TO FALLING PRECIPITATION.
&&
.LONG TERM /WEDNESDAY THROUGH FRIDAY/...
THE SUPPORT FROM THE STRENGTHENING 250 MB JET SHOULD BE TO OUR EAST
BY MONDAY EVENING...WITH THE REINFORCING COLD ARCTIC AIR BLOWING
IN.
LIKE YESTERDAY AND THE DAY BEFORE THAT...WE WILL CONTINUE TO HOLD
ONTO TO HIGHER POPS LONGER IN SOME ACCUMULATING SNOW SHOWERS MONDAY
EVENING THAN MODEL GUIDANCE....AS DEW POINTS LOWER IN THE COLD AIR
ADVECTION.
DRIER ARCTIC AIR TAKES CONTROL FOR TUESDAY WITH LOW DEW POINTS. SO
DESPITE THE 850 MB THERMAL TROF...DO NOT WANT TO BE AS PESSIMISTIC
AS WE USUALLY ARE ON CLOUDS IN THE LOW LEVEL THERMAL TROF.
YET...STILL LEFT SOME FLAKES IN THE AIR WELL THROUGH TUESDAY NIGHT
FOR THE MOUNTAIN COUNTIES.
COLDEST DAY MAXIMUM READINGS SHOULD BE TUESDAY. MOST LOWLAND
READINGS IN THE 20S FOR MAXIMUM. OUR SMALL AREA AOA 4000 FEET SHOULD
REMAIN IN SINGLE DIGITS DURING THE DAY ON TUESDAY.
AN IDEAL CLEAR/CALM NIGHT MAY BE HARD TO FIND...SINCE HIGH PRESSURE
CENTER NOT DIRECTLY OVER US. BUT WINDS SHOULD DIMINISH TUESDAY
NIGHT. SO COLDEST TEMPERATURES FOR LOWLANDS LIKELY TUESDAY
NIGHT/EARLY WEDNESDAY.
CONTINUED DRY WEDNESDAY INTO THURSDAY.
WARM AIR ADVECTION MOISTURE INCREASES THURSDAY NIGHT INTO FRIDAY.
WILL HAVE CHANCE POPS SPREADING SW TO NE OVERNIGHT THURSDAY NIGHT
INTO FRIDAY.
&&
.AVIATION /09Z SATURDAY THROUGH WEDNESDAY/...
VFR CONDITIONS WILL PREVAIL THROUGH THE TAF PERIOD EXCEPT FOR SOME
MVFR CIGS OVER KBKW EARLY THIS MORNING. AN INCREASE IN HIGH AND
MIDDLE LEVEL CLOUDS CAN BE EXPECTED AS THE DAY PROGRESSES. THIS
TREND CONTINUES TONIGHT WITH PASSAGE OF AN UPPER LEVEL
DISTURBANCE.
FLOW SURFACE AND ALOFT WILL BE LIGHT TODAY COURTESY OF HIGH
PRESSURE. FLOW ALOFT INCREASES OUT OF SW 20 TO 25 KTS TONIGHT BUT
SURFACE WINDS ACROSS TAF SITES WILL REMAIN LIGHT.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z SUNDAY...
FORECAST CONFIDENCE: HIGH
ALTERNATE SCENARIOS: NONE
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE SAT 11/15/14
UTC 1HRLY 06 07 08 09 10 11 12 13 14 15 16 17
EST 1HRLY 01 02 03 04 05 06 07 08 09 10 11 12
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 06Z SUNDAY...
IFR POSSIBLE SUNDAY NIGHT INTO TUESDAY IN PRECIPITATION AND
CLOUDS.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...KTB/RPY/30
NEAR TERM...30
SHORT TERM...RPY
LONG TERM...KTB
AVIATION...30
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
135 AM EST SAT NOV 15 2014
.SYNOPSIS...
HIGH PRESSURE LINGERS TODAY. NEXT SYSTEM WITH DEEPER MOISTURE
SUNDAY NIGHT INTO MONDAY. REINFORCING COLD AIR ARRIVES MONDAY
NIGHT INTO TUESDAY. COLDEST DAY TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
STRATUS HANGING TOUGH OVER THE N MOUNTAINS ATTM WHICH IS KEEPING
TEMPS UP AT EKN COMPARED A HAIR. EXPECT THESE CLOUDS TO DISSIPATE
PER HRRR OVER THE NEXT SEVERAL HRS. ELSEWHERE...QUITE COLD WITH
TEMPS RUNNING A BIT BLOW FCST CURVE IN THE OUTLYING AREAS.
ADJUSTED HOURLY TEMPS AND MINT GRID DOWN A FEW
DEGREES...ESPECIALLY AWAY FROM URBAN CENTERS. MID TEENS LOOK LIKE
A GOOD BET ACROSS THESE LOCATIONS ACROSS THE LOWLANDS. IF THE
CLOUDS OVER THE MOUNTAINS CAN CLEAR IN TIME...THEN SOME HIGH
SINGLE NUMBERS ARE POSSIBLE OVER THE HIGH RIDGES. SNOWSHOE
CURRENTLY SITTING AT 11F.
AS FOR TODAY...THE SUN WILL FINALLY MAKE AN APPEARANCE...ALBEIT
WITH A SHORT STAY. SOME CIRRUS WILL STREAK IN DURING THE FIRST
HALF OF TODAY...FOLLOWED BY INCREASE IN MID LEVEL CLOUDS
ASSOCIATED WAA ALOFT LATE IN THE AFTERNOON AND EARLY EVENING /FROM
SW TO NE/. H85 TEMPS WILL MODERATE BY ALMOST 10 DEGREES TODAY.
STILL...WITH H925 TEMPS STILL ON THE COOL SIDE...FELT ROLLING WITH
COOLER GUIDANCE /A LA LOCAL IN HOUSE MOS/ WAS THE BEST OPTION. AS
SUCH...HAVE SOME MID 30S FOR THE LOWLANDS WITH LOWER 30S FOR THE
HIGH TERRAIN. BIGGEST IMPROVEMENT IN TEMPS COMPARED TO YESTERDAY
WILL BE FELT IN THE HIGHER ELEVATIONS WHERE SNOWSHOE SHOULD MAKE A
RUN TOWARD UPPER 20S LATE IN THE DAY VERSUS LOW TEENS OBSERVED YESTERDAY.
A MID LEVEL DISTURBANCE WILL RACE THROUGH THE REGION TONIGHT.
HOWEVER...WITH LITTLE FANFARE OTHER THAN THE INCREASE IN MIDDLE
LEVEL CLOUDS. THE WAA ALOFT CONTINUES THOUGH...SO HAVE HIGHEST
RIDGES HOLDING NEAR STEADY IF NOT RISING TOWARD MORNING WITH
GENERALLY MID 20S IN THE LOWLANDS.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY/...
SURFACE HIGH PRESSURE EXITING TO THE EAST AT THE START OF THE
PERIOD. MOISTURE BEGINS INCREASING SATURDAY NIGHT INTO SUNDAY...AND
AS A WEAK SHORTWAVE PASSES TO OUR NORTH WE COULD SQUEEZE OUT A
LITTLE SNOW ACROSS NW CORNER OF CWA. STILL PRETTY DRY AT THE
SURFACE...SO ONLY HAVE LOW CHANCE POPS WITH THIS. MOISTURE CONTINUES
TO INCREASE THROUGH SUNDAY. SOME UNCERTAINTY ON JUST HOW QUICKLY THE
COLUMN WILL SATURATE AND PRECIP WILL BEGIN. MODELS SEEM TO HAVE
BACKED OFF JUST A TOUCH...SO REDUCED POPS SOME SUNDAY MORNING.
POPS RAMP UP PRETTY QUICKLY AS WARM AIR ADVECTION CONTINUES MOISTURE
INFLOW AND STARTS PROVIDING LIFT. IN REALITY WILL LIKELY BE AN EVEN
TIGHTER POP GRADIENT THAN CURRENT FORECAST AS COLUMN SATURATES. WITH
THE WARM AIR ADVECTION FOLLOWED BY COLD SURGE FROM THE
WEST...ANTICIPATE A WARM WEDGE SETTING UP ACROSS THE WV LOWLANDS FOR
SUNDAY NIGHT INTO MONDAY. FARTHER WEST...NEAR THE OHIO
RIVER...COLDER AIR WILL PUSH IN CHANGING RAIN TO SNOW SUNDAY NIGHT.
MODELS IN GOOD AGREEMENT WITH JET DYNAMICS TAKING OVER SUNDAY
NIGHT...INCREASING PRECIP EFFICIENCY AS DIVERGENCE FROM A 130-150KT
JET STREAK SETS UP OVER THE OHIO RIVER VALLEY. MODELS ALSO IN GOOD
AGREEMENT ON 850MB TEMPERATURE FIELD...WITH RATHER TIGHT GRADIENT
CENTERED ROUGHLY OVER THE OHIO RIVER. THIS WILL ALLOW ACCUMULATING
SNOW FROM THE OHIO RIVER WEST...WITH MORE OF A RAIN/SNOW/SLEET MIX
EAST OF THE RIVER...AND EVEN JUST RAIN ACROSS THE SOUTHERN COAL
FIELDS INTO MONDAY AFTERNOON. WITH THE COLD AIR AND JET STREAK
LINING UP PRETTY WELL...EXPECTING A GOOD BAND OF SNOW DEVELOPING
OVER SE OHIO. HAVE GENERALLY 2-4 INCHES. ANTICIPATE A BAND OF 4 OR
MORE SOMEWHERE JUST WEST OF THE OHIO RIVER...BUT CANNOT PIN POINT
THAT THIS FAR OUT.
THAT WILL PUT US RIGHT AT THE WINTER WEATHER ADVISORY/WARNING
CRITERIA LINE WHERE EVER THAT BAND SETS UP. WILL CONTINUE MENTION OF
POSSIBLE WINTER HEADLINES IN HWO...AND HOPEFULLY THE HIGHER
RESOLUTION NEAR TERM MODELS WILL BEGIN PROVIDING USEFUL INPUT INTO
THE MOST LIKELY PLACEMENT FOR THE BAND OF HIGHER SNOW OVER THE NEXT
SEVERAL SHIFTS.
FARTHER EAST...ACROSS THE HIGHEST TERRAIN OF THE WV
MOUNTAINS...THERE COULD BE A BRIEF PERIOD OF SOME LIGHT FREEZING
RAIN AND/OR SLEET AS TEMPERATURES ALOFT WARM SUNDAY NIGHT.
AS THE COLD AIR CONTINUES TRYING TO ERODE THE WARM WEDGE MONDAY
AND THE UPPER LEVEL JET SINKS SE ACROSS FORECAST AREA...HAVE ANY
REMAINING RAIN CHANGING BACK OVER TO SNOW FROM WEST TO
EAST...BECOMING ALL SNOW BY 22Z-23Z.
BLENDED IN GFS/ECMWF INTO PREVIOUS TEMP FORECAST THROUGH SUNDAY
NIGHT...AND THEN WENT NON-DIURNAL MONDAY AS COLD AIR SURGES IN.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
THE SUPPORT FROM THE STRENGTHENING 250 MB JET SHOULD BE TO OUR EAST
BY MONDAY EVENING...WITH THE REINFORCING COLD ARCTIC AIR BLOWING
IN.
LIKE YESTERDAY AND THE DAY BEFORE THAT...WE WILL CONTINUE TO HOLD
ONTO TO HIGHER POPS LONGER IN SOME ACCUMULATING SNOW SHOWERS MONDAY
EVENING THAN MODEL GUIDANCE....AS DEW POINTS LOWER IN THE COLD AIR
ADVECTION.
DRIER ARCTIC AIR TAKES CONTROL FOR TUESDAY WITH LOW DEW POINTS. SO
DESPITE THE 850 MB THERMAL TROF...DO NOT WANT TO BE AS PESSIMISTIC
AS WE USUALLY ARE ON CLOUDS IN THE LOW LEVEL THERMAL TROF.
YET...STILL LEFT SOME FLAKES IN THE AIR WELL THROUGH TUESDAY NIGHT
FOR THE MOUNTAIN COUNTIES.
COLDEST DAY MAXIMUM READINGS SHOULD BE TUESDAY. MOST LOWLAND
READINGS IN THE 20S FOR MAXIMUM. OUR SMALL AREA AOA 4000 FEET SHOULD
REMAIN IN SINGLE DIGITS DURING THE DAY ON TUESDAY.
AN IDEAL CLEAR/CALM NIGHT MAY BE HARD TO FIND...SINCE HIGH PRESSURE
CENTER NOT DIRECTLY OVER US. BUT WINDS SHOULD DIMINISH TUESDAY
NIGHT. SO COLDEST TEMPERATURES FOR LOWLANDS LIKELY TUESDAY
NIGHT/EARLY WEDNESDAY.
CONTINUED DRY WEDNESDAY INTO THURSDAY.
WARM AIR ADVECTION MOISTURE INCREASES THURSDAY NIGHT INTO FRIDAY.
WILL HAVE CHANCE POPS SPREADING SW TO NE OVERNIGHT THURSDAY NIGHT
INTO FRIDAY.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
VFR CONDITIONS WILL PREVAIL THROUGH THE TAF PERIOD EXCEPT FOR SOME
MVFR CIGS OVER KBKW EARLY THIS MORNING. AN INCREASE IN HIGH AND
MIDDLE LEVEL CLOUDS CAN BE EXPECTED AS THE DAY PROGRESSES. THIS
TREND CONTINUES TONIGHT WITH PASSAGE OF AN UPPER LEVEL
DISTURBANCE.
FLOW SURFACE AND ALOFT WILL BE LIGHT TODAY COURTESY OF HIGH
PRESSURE. FLOW ALOFT INCREASES OUT OF SW 20 TO 25 KTS TONIGHT BUT
SURFACE WINDS ACROSS TAF SITES WILL REMAIN LIGHT.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z SUNDAY...
FORECAST CONFIDENCE: HIGH
ALTERNATE SCENARIOS: NONE
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE SAT 11/15/14
UTC 1HRLY 06 07 08 09 10 11 12 13 14 15 16 17
EST 1HRLY 01 02 03 04 05 06 07 08 09 10 11 12
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 06Z SUNDAY...
IFR POSSIBLE SUNDAY NIGHT INTO TUESDAY IN PRECIPITATION AND
CLOUDS.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...KTB/RPY/30
NEAR TERM...30
SHORT TERM...MZ
LONG TERM...KTB
AVIATION...30
AREA FORECAST DISCUSSION
NWS NORMAN OK
1054 PM CST FRI NOV 14 2014
.DISCUSSION...
AVIATION DISCUSSION FOR THE 06Z TAFS IS BELOW.
&&
.AVIATION...
OVERALL...VFR CONDITIONS ARE EXPECTED TO CONTINUE.
A LIGHT WINTRY MIX OF PRECIPITATION IS POSSIBLE NEARLY ANYWHERE
THROUGH 18Z. CONFIDENCE OF PRECIPITATION OCCURRENCE REMAINS TOO
LOW TO MENTION AT THIS TIME AS MOST PRECIPITATION WILL LIKELY
STAY NORTH OF THE OKLAHOMA KANSAS STATELINE.
THERE IS AN OUTSIDE CHANCE FOR MVFR CEILINGS TO DEVELOP
ACROSS THE AREA AFTER 09Z...BUT DID NOT MENTION DUE TO LOW
CONFIDENCE.
SOUTH TO SOUTHEAST WINDS WILL BECOME GUSTY AT MANY SITES
09-16Z...THEN DIMINISH 20-24Z. A COLD FRONT WILL BRING A WIND
SHIFT TO THE NORTH NEAR KWWR AND KGAG AROUND 21Z...AND TO OTHER
SITES 22-02Z.
MBS
&&
.PREV DISCUSSION... /ISSUED 719 PM CST FRI NOV 14 2014/
UPDATE...
ADJUSTED PRECIPITATION TYPE ACROSS NORTHERN OKLAHOMA AFTER
MIDNIGHT TONIGHT THROUGH EARLY SATURDAY AFTERNOON TO INCLUDE
SLEET.
DISCUSSION...
A LIGHT WINTRY MIX OF MAINLY LIGHT SLEET AND LIGHT SNOW
IS POSSIBLE AFTER MIDNIGHT TONIGHT THROUGH 3 PM SATURDAY
ACROSS NORTHERN OKLAHOMA.
LATEST HRRR RUNS HAVE BEEN DEPICTING LIGHT PRECIPITATION
DEVELOPING AS LIFT INCREASES IN NORTHWEST OKLAHOMA MIDNIGHT TO
4 AM TONIGHT...THEN SPREADING EAST...AFFECTING AREAS NORTH OF A
GAGE TO STILLWATER LINE. FORECAST PRECIPITATION CHANCES ARE IN
GOOD SHAPE AND WERE NOT ALTERED.
BASED ON THE LATEST 00Z NEARBY UPPER AIR SOUNDINGS AND TOP DOWN
SOUNDING METHODOLOGY...BELIEVE ANY PRECIPITATION REACHING THE
GROUND WOULD MAINLY BE LIGHT SLEET AS PRECIPITATION ALOFT WOULD
PARTIALLY OR COMPLETELY MELT WITH A 720-800 MB WARM NOSE OF +1 TO
+6C THEN REFREEZE 800-850 MB WITH TEMPERATURES AROUND -9C.
LIGHT SNOW WOULD BE POSSIBLE IF PRECIPITATION INTENSITY BECOMES
HEAVY ENOUGH TO ALLOW EVAPORATIONAL COOLING TO ERODE THE MID
LEVEL WARM NOSE. LATEST RAP13 RUNS HINT THAT THIS COULD OCCUR
NORTH OF AN ALVA TO STILLWATER LINE AFTER 4 AM TONIGHT.
REGARDLESS OF PRECIPITATION TYPE...ANY PRECIPITATION AMOUNTS
APPEAR TO BE LIGHT IN NORTHERN OKLAHOMA WITH THE HEAVIER AMOUNTS
FARTHER NORTH ACROSS NORTHERN KANSAS LATE TONIGHT INTO SATURDAY.
COULD NOT COMPLETELY RULE OUT A DUSTING OF SLEET OR SNOW
ACCUMULATIONS MIDNIGHT TONIGHT TO 3 PM SATURDAY OVER NORTHERN
OKLAHOMA...BUT THINK IMPACTS WILL BE MINIMAL DUE TO THE LIGHT
NATURE OF PRECIPITATION AND LACK OF SIGNIFICANT NEARBY MOISTURE.
HOWEVER...WITH SURFACE TEMPERATURES BELOW FREEZING...A FEW SLICK
SPOTS COULD DEVELOP.
WILL CONTINUE TO MONITOR. PRODUCTS HAVE BEEN UPDATED. NO WINTER
WEATHER ADVISORIES ARE EXPECTED TO BE ISSUED FOR TONIGHT THROUGH
SATURDAY AFTERNOON AT THIS TIME.
MBS
PREV DISCUSSION... /ISSUED 255 PM CST FRI NOV 14 2014/
DISCUSSION...
SHORT TERM...(TONIGHT-SUNDAY NIGHT)
LOW CLOUDS SHOULD CONTINUE TO ERODE THROUGH THE AFTERNOON
WHILE HIGH CLOUDS SLOWLY INCREASE. A QUICK MOVING SYSTEM WILL
APPROACH TONIGHT AND SHOULD CLEAR THE SOUTHERN PLAINS BY SATURDAY
AFTERNOON. THE OVERALL TREND WITH THIS SYSTEM...HAS BEEN BETTER
CHANCES FOR PRECIPITATION MAINLY NORTH OF OKLAHOMA. WILL KEEP LOW
CHANCES FOR LIGHT SNOW ACROSS NORTHERN OKLAHOMA FROM LATE TONIGHT
THROUGH LATE SATURDAY MORNING. A WARM NOSE BELOW 7H ACROSS
NORTHWEST OKLAHOMA MAY RESULT IN SOME SLEET OVERNIGHT.
PRECIPITATION AMOUNTS WILL BE LIGHT WITH THIS SYSTEM.
ANOTHER PUSH OF RATHER COLD AIR WILL BEGIN TO ENTER NORTHWEST
OKLAHOMA LATE SATURDAY AFTERNOON AND EVENING. GUSTY NORTHERLY
WINDS CAN BE EXPECTED ACROSS MOST OF OKLAHOMA BY EARLY/MID
SUNDAY MORNING. AN APPROACHING WAVE WILL BRING A DECENT CHANCE
OF LIGHT SNOW SUNDAY MORNING AND AFTERNOON. MOST MODELS INDICATE
THE BEST LIFT OCCURRING ACROSS NORTHERN OKLAHOMA SUNDAY MORNING
THEN SHIFTING SOUTHWARD DURING THE AFTERNOON. A LITTLE UNSURE ON
AMOUNTS...BUT EXPECT SOME AREAS NORTH OF OF I-40 SHOULD SEE AN
INCH OF SNOW WITH 2 INCH AMOUNTS POSSIBLE. WITH THE RECENT COLD
WEATHER...ANY SNOW THAT FALLS WILL ACCUMULATE AND MAY CAUSE MINOR
TRAFFIC DELAYS.
LONG TERM...(MONDAY-THURSDAY)
A GRADUAL WARMING TREND WILL BEGIN EARLY NEXT WEEK, WITH SURFACE
WINDS BECOMING SOUTHERLY BY MIDWEEK. AN UPPER WAVE WILL MOVE
ACROSS THE AREA ON THURSDAY, BRINGING LOW POPS FOR RAIN ACROSS
SOUTHEAST OKLAHOMA. THE COLD FRONT ASSOCIATED WITH THIS SYSTEM
APPEARS TO BE WEAK, STALLING ACROSS NORTHWEST OKLAHOMA BEFORE
LIFTING BACK TO THE NORTH.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 27 46 27 29 / 0 20 10 50
HOBART OK 28 48 27 29 / 10 10 10 40
WICHITA FALLS TX 29 53 32 33 / 0 10 10 30
GAGE OK 25 42 20 29 / 20 10 30 60
PONCA CITY OK 25 41 24 29 / 10 30 20 60
DURANT OK 28 45 34 39 / 0 10 20 30
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
04/17/17
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1157 PM EST FRI NOV 14 2014
.SYNOPSIS...
THE ANOMALOUS UPPER TROUGH WILL BRIEFLY LIFT OUT OVER THE WEEKEND
AS SURFACE HIGH PRESSURE SLIDES BY JUST TO THE SOUTH OF
PENNSYLVANIA. AN EVEN DEEPER TROUGH WILL FORM OVER THE GREAT
LAKES AND NORTHEAST CONUS EARLY NEXT WEEK. THIS DEEPENING TROUGH
WILL HELP TO FORM A FAST MOVING AREA OF LOW PRESSURE THAT WILL
TRACK FROM THE DEEP SOUTH TO THE SOUTHERN NEW ENGLAND COAST BY
MONDAY EVENING. THIS WEATHER FEATURE WILL BRING A LIKELIHOOD OF A
LIGHT TO MODERATE SNOWFALL MONDAY ACROSS AT LEAST THE NORTHWEST
HALF OF PENNSYLVANIA. MIXED PRECIPITATION AND RAIN ARE MOST
LIKELY OVER THE CENTRAL AND SOUTHEAST ON MONDAY.
&&
.NEAR TERM /UNTIL 7 AM SATURDAY MORNING/...
10 PM UPDATE...
SNOW SHOWERS ARE STILL MAINLY CELLULAR IN ONLY SEMI-CONCENTRATED
BANDS. CELLS MOVING VERY QUICKLY AND CIGS GET HIGH PRETTY QUICKLY
AWAY FROM THE LAKE. EVEN KERI IS HIGH-MVFR WHEN IT DOES SNOW
THERE. THUS...ACCUMS FOR THE OVERNIGHT LOOK ON TRACK. AS
EARLIER...HRRR AND RAP HANDLING THE NEAR-TERM WAGGLE TO THE SOUTH
OF THE BROAD BANDS. THEY AND THE NEWEST NAM CONTINUE TO SINK THE
BANDS SOUTHWARD FOR A FEW MORE HOURS...THEN STALL FOR A FEW HOURS
AND SHOVE THEM BACK TO THE NORTH AS THE CENTER OF THE BIG SFC HIGH
MOVES INTO THE CENTRAL APPALACHIANS.
730 PM UPDATE...
HRRR AND RUC HANDLING THE SHIFT OF THE BANDS TO THE SOUTH WITH
VEERING LOW LEVEL WINDS VERY NICELY. THE NEAR TERM PREDICTIONS
PORTRAY THE CONTINUED VEERING THROUGH MIDNIGHT OR A LITTLE
LATER...THEN A TURN AROUND AND BACKING TO A GENERALLY SWRLY FLOW
IN THE CLOUD LAYER BY SUNRISE. THUS...HAVE HIGH CONFIDENCE IN
KEEPING ALL THE WEATHER ELEMENTS VERY CLOSE TO CURRENT
PROJECTIONS. LES ADVY STILL LOOKING GOOD FOR WARREN CO.
PREV...
A PERSISTENT...COLD NORTHWESTERLY FLOW OVR THE GRT LKS WILL
CONTINUE TO PRODUCE FREQUENT SNOW SHOWERS ACROSS THE NW MTNS
AND LAUREL HIGHLANDS TONIGHT WITH ADDITIONAL LIGHT ACCUMULATIONS
OF A COATING TO ONE INCH ACROSS MANY AREAS NEAR...AND JUST TO THE
WEST OF RT 219.
HIGH RES MODELS SHOW DIRECTIONAL SHEAR IN THE LOWEST FEW KM
BECOMING BETTER ALIGNED LATE THIS AFTERNOON THROUGH MUCH OF
TONIGHT...WHICH WILL CREATE 2 OR 3...MORE ORGANIZED LES BANDS
/THAT WILL PENETRATE FURTHER INLAND THANKS TO A MEAN 20KT FLOW
FROM 300 DEG IN THE LOWEST 2 KM/.
BRIEF PERIODS OF 1/4-1/2SM SNOW WILL OCCUR WITHIN THESE BANDS.
EXTENDED THE LES ADVISORY FOR WARREN COUNTY THROUGH 12Z SATURDAY
AS THE PASSAGE OF A WEAK UPPER SHORT WAVE AND SFC TROUGH WILL LEAD
TO A BETTER UPSTREAM MOISTURE TAP OFF SOUTHERN LAKE HURON.
AREAS OF MORE SHALLOW BKN-OVC STRATO CU ACROSS THE NORTH-CENTRAL
MTNS AND CENTRAL RIDGE AND VALLEY REGION /INCLUDING THE SUSQ
VALLEY/ WILL SUPPORT MAINLY FLURRIES AN PERHAPS A BRIEF 2-3SM VSBY
SNOW SHOWER LATE TODAY AND TONIGHT WITH A FEW LOCATIONS SEEING A
POWDERY DUSTING OF SNOW.
MIN TEMPS EARLY SATURDAY WILL BE IN THE LOWER TO MID 20S...BUT THE
WEST TO NORTHWEST BREEZE WILL DECREASE TO ABOUT 6-8 KTS AFTER 02Z
SAT.
&&
.SHORT TERM /7 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
EXPECT ANY REMAINING LAKE EFFECT SNOW BANDS TO SHIFT QUICKLY NORTH
OR DISSIPATE DURING LATE MORNING/EARLY AFTERNOON HOURS AS SHEAR
WITHIN THE SFC-800 INCREASES...BEFORE THE MEAN WIND IN THIS LAYER
GRADUALLY BACKS TO THE WEST-SOUTHWEST IN THE AFTERNOON.
ACROSS THE CENTRAL AND SERN ZONES...SOME MORNING CLOUDS AND
FLURRIES WILL LIKELY YIELD TO INCREASING AMOUNT OF SUNSHINE
THROUGH THE SHALLOW STRATO CU DECK.
PARTLY TO MOSTLY CLOUDY SKIES IN THE FORM OF MAINLY ALTO CU CLOUDS
EXPECTED FOR SAT NIGHT AS A WARM FRONT LIFTS NE FROM THE OHIO
VALLEY. A BIT OF LIGHT SNOW OR FLURRIES IS POSSIBLE SAT
NIGHT/EARLY SUNDAY ACROSS THE NW HALF OF THE STATE WITH VERY MINOR
ACCUMS AT MOST.
MAX TEMPS SAT WILL BE IN THE L-M 30S ACROSS THE NRN AND WRN
MTNS...AND UPR 30S TO L40S FURTHER SE THROUGH THE SUSQ VALLEY.
LOW TEMPS AT DAYBREAK SUNDAY WILL BE IN THE M-U 20S ACROSS THE
MTNS AND 30-35 ELSEWHERE.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
COLD WEATHER PATTERN CONTINUES THROUGH NEXT WEEK...
ADVISORY LEVEL SNOW ACCUMULATION POSSIBLE ON MONDAY...
UPPER LEVEL RIDGING FROM THE NW COAST TO ALASKA WILL SUSTAIN AND
MAINTAIN A DEEP TROUGH AND UNSEASONABLY COLD AIRMASS OVER THE AREA
THROUGH MUCH OF NEXT WEEK. FORECAST CONFIDENCE REMAINS VERY HIGH
IN A PROLONGED STRETCH OF WELL-BELOW NORMAL TEMPERATURES FOR THIS
TIME OF YEAR WITH THE CORE OF THE COLD IMPACTING THE CWA TUE-WED.
MODELS CONTINUE TO SHOW A LEAD SHORTWAVE CROSSING THE ERN GREAT
LAKES ON SUNDAY...WHICH COULD SPREAD SOME LIGHT SNOW/RAIN INTO THE
WESTERN COUNTIES DURING THE DAY. RELOADING CENTRAL US TROUGH
BECOMES WELL ESTABLISHED BY 12Z MONDAY WITH CORE OF NEGATIVE
HEIGHT ANOMALIES /-3 STD/ SPREADING EWD FROM THE UPPER MIDWEST
THROUGH THE OH VALLEY.
THERE IS AN EMERGING CONSENSUS AMONG THE GLOBAL GUIDANCE IN A
BROAD AREA OF PCPN OVERSPREADING THE AREA ON MONDAY...AS MOISTURE
AND LIFT BECOME ENHANCED WITHIN THE ENTRANCE REGION OF A STRONG
UPPER JET EAST OF THE DEEP TROUGH...ALONG SHARPENING LOW LEVEL
THERMAL GRADIENT/FRONTAL AXIS MARKING LEADING EDGE OF ARCTIC
AIRMASS. FOLLOWED WPC BLEND FOR QPF AND THERMAL PROFILES WHICH
SUPPORTS POTENTIAL FOR ADVISORY LEVEL SNOW ACCUMULATIONS /2-4
INCHES/ OVER THE NW 1/2 OF THE CWA. FURTHER SOUTH/EAST...A RAIN TO
SNOW MIX TO CHANGEOVER SCENARIO SEEMS LKLY WITH LOWER ACCUMS GIVEN
INITIALLY WARM BLYR. ALTHOUGH THE PTYPE DETAILS AND SNOW ACCUMS
ARE STILL UNCERTAIN...CONFIDENCE IN WINTER WEATHER IMPACTS TO THE
MONDAY MORNING COMMUTE IS INCREASING ESPECIALLY OVER THE WRN 1/2
OF THE CWA. WILL ADD WORDING INTO THE HWO.
A FRIGID SURGE OF ARCTIC AIR WILL BLAST INTO THE REGION BEHIND
THIS SYSTEM ON TUESDAY AND PERSIST THRU THE MIDDLE OF NEXT WEEK.
MEAN 85H TEMPS ARND -15C IN BOTH THE GEFS/ECENS TRANSLATE INTO
HIGH TEMPS BELOW FREEZING FOR MOST OF CENTRAL PA TUE/WED. WIND
CHILLS IN THE LOW TEENS AND SINGLE DIGITS ARE LKLY AND MAY EVEN
DIP BELOW 0F OVER THE WRN MTNS. THE TRANSITION BACK TO A COLD
CYCLONIC NW FLOW PATTERN WILL FAVOR LAKE EFFECT AND TERRAIN
ENHANCED SNOW SHOWERS OVER THE NW MTNS WITH COLD AND DRY
CONDITIONS FROM THE CENTRAL RIDGES INTO THE LWR SUSQ VLY.
SOME MODERATION IN TEMPS MAY BE IN SIGHT BY THE END OF NEXT WEEK
AS MODELS AND ENSEMBLES SHOW THE UPSTREAM PATTERN CONFIGURATION
BREAKING DOWN.
&&
.AVIATION /04Z SATURDAY THROUGH WEDNESDAY/...
LITTLE CHANGE IS EXPECTED ACRS THE REGION TONIGHT AS COLD AIR
RIDING SOUTHEAST ACROSS THE RELATIVELY WARMER WATERS OF THE GREAT
LAKES IS LIFTED OVER THE HIGHER TERRAIN IN WESTERN PA.
THE BIGGEST AVIATION CONCERN TONIGHT WILL BE THE LAKE ENHANCED
SNOW SHOWERS ACROSS THE NORTHWEST MOUNTAINS. IT IS NOT PERSISTENT
ENOUGH TO ALLOW FOR CIGS AND VSBYS TO REMAIN IFR...BUT CONDITIONS
WILL DROP DOWN TO IFR BETWEEN 04Z TO 09Z...WHEN LAKE EFFECT
SHOWERS WILL FADE AS WINDS SHIFT TO A MORE WESTERLY COMPONENT AND
MOISTURE WILL BE CUT OFF.
VFR TO HIGH-END MVFR STRATOCU AND SCT LIGHT SNOW SHOWERS/FLURRIES
WILL SPILL INTO CENTRAL MTNS TONIGHT. WINDS WILL SETTLE TO 6-8
KTS TONIGHT.
VFR WILL DOMINATE THE WEATHER PATTERN TOMORROW WITH ONLY POSSIBLE
MVFR AT BFD...MAINLY TOMORROW NIGHT.
OUTLOOK...
SAT...AM SNOW SHOWERS/REDUCED VSBYS POSS AT KBFD AND JST.
SUN...SNOW SHOWERS/REDUCED VSBYS POSS AT KBFD.
MON...LGT-MDT SNOW/LOW CIGS EXPECTED ACROSS THE NW HALF OF PA.
RAIN/MIXED PRECIP AND LOW CIGS POSS SE.
TUE AND WED...BLUSTERY AND VERY COLD WITH SNOW SHOWERS AND AREAS
OF REDUCED CIGS/VSBYS - MAINLY ACROSS THE NW HALF OF PENN.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
LAKE EFFECT SNOW ADVISORY UNTIL 7 AM EST SATURDAY FOR PAZ004.
&&
$$
SYNOPSIS...DANGELO/LAMBERT
NEAR TERM...DANGELO/LAMBERT
SHORT TERM...LAMBERT
LONG TERM...STEINBUGL
AVIATION...LAMBERT/CERU
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
253 AM MST SAT NOV 15 2014
.SHORT TERM...(TODAY THROUGH MONDAY NIGHT)
ISSUED AT 253 AM MST SAT NOV 15 2014
MAIN CONCERN IN THE NEAR TERM IS ACCUMULATING SNOW ACROSS SOUTHEAST
WY AND THE WESTERN NE PANHANDLE. WINTER WEATHER ADVISORIES LOOK GOOD
AND HAVE MADE NO CHANGES WITH THE MORNING FCST PACKAGE. HAVE SEEN A
RELATIVE LULL IN SNOW SHOWERS OVERNIGHT WITH SUBSIDENCE AND SOMEWHAT
DRY AIR ALOFT. HOWEVER...POTENT MIDLVL SHORTWAVE EVIDENT ON MORNING
WATER VAPOR LOOP OVER THE PAC NW WILL MOVE SOUTHEAST TODAY. COOLING
CLOUD TOPS OVER CENTRAL WY SUGGEST AN UPTICK IN PCPN COVERAGE OVER
THE NEXT FEW HOURS...SO WILL KEEP CATEGORICAL POPS GOING. LOOKING AT
TWO DISTINCT AREAS OF SNOW ACCUMULATIONS. FIRST ACROSS THE NORTHERN
TIER OF COUNTIES WITH FRONTOGENESIS ALONG THE SFC FRONT. SECOND
ALONG AND WEST OF THE LARAMIE RANGE WITHIN THE LEFT EXIT REGION OF A
105 KT H25 JET STREAK NOW ENTERING NORTHERN UT. BOTH AREAS COINCIDE
WELL WITH A MIDLVL MOISTURE PLUME OVERSPREADING THE CWA. A GENERAL 2
TO 5 INCH SNOWFALL SEEMS PROBABLE IN THESE CORRIDORS. EVEN IF WE DO
NOT SEE ADVISORY CRITERIA AMOUNTS...NORTHWEST WINDS WILL GUST IN
EXCESS OF 30 MPH TODAY WHICH WILL CREATE BLOWING/DRIFTING. WEBCAMS
ALREADY LOOK QUITE NASTY IN THE RAWLINS IN ELK MOUNTAIN AREAS AS OF
09Z THIS MORNING. THOUGHT ABOUT A TEMPORAL EXTENTION OF THE ADVISORY
THROUGH THE AFTN FOR BLOWING SNOW AFTER ACCUMULATIONS END...BUT WILL
LET THE DAY SHIFT MONITOR CONDITIONS TO SEE JUST HOW BAD VISIBILITY
BECOMES LATER ON.
SNOW HAS BEEN DIFFICULT TO COME BY IN THE CHEYENNE AREA SO FAR. IT
STILL LOOKS LIKE WE HAVE A WINDOW OF OPPORTUNITY IN THE 12-15Z TIME
FRAME AS THE NAM SHOWS A BAND OF MODERATE H7 FRONTOGENESIS FROM THE
SOUTHERN LARAMIE RANGE EAST INTO KIMBALL COUNTY NE. MAY BE ENOUGH
FOR A QUICK 1 TO 2 INCHES...BUT NOT MUCH MORE. WITH NORTHWEST WINDS
GUSTING 25 TO 35 MPH...DAY SHIFT MIGHT NEED TO CONSIDER A BLOWING
SNOW ADVISORY FOR CENTRAL AND EASTERN LARAMIE COUNTY. THE MOUNTAINS
STILL LOOK PRIME FOR 8 TO 12 INCHES OF TOTAL ACCUMULATION. NVA WILL
SPREAD ACROSS THE AREA BY LATE AFTN...SO EXPECT A GRADUAL DECREASE
IN PCPN COVERAGE FROM NORTHWEST TO SOUTHEAST THROUGH EARLY EVE. DRY
AFTER 00Z OUTSIDE OF A FEW FLURRIES. STRONG LLVL COLD AIR ADVECTION
WILL CONTINUE TODAY WITH THE FROPA...WITH GFS H7 TEMPS PLUNGING TO
THE -17C TO -20C RANGE BY 00Z SUN. SURFACE TEMPS WILL MOST LIKELY
HOLD STEADY TODAY OR EVEN FALL SLIGHTLY INTO THE AFTN. DRYING ALOFT
SIGNALS CLEARING INTO TONIGHT...AND WITH FRESH SNOWPACK COMES VERY
COLD TEMPERATURES TONIGHT. GUSTY WEST WINDS MIGHT KEEP THINGS MIXED
ENOUGH TO PREVENT TEMPERATURES FROM REALLY TANKING...BUT IT WILL BE
SUFFICIENT FOR DANGEROUS WIND CHILLS BETWEEN -20 AND -30F. EXPECT
WIND CHILL ADVISORIES WILL BE NECESSARY.
BOTH THE NAM AND GFS SUGGEST A FAIRLY POTENT SHORTWAVE DIVING SOUTH
ACROSS THE WESTERN DAKOTAS ON SUN AFTN. WHILE THIS DOES PROVIDE A
REINFORCING SHOT OF COLD AIR...THE GOOD CAA DOES NOT ARRIVE UNTIL
LATE. AS SUCH...EXPECT A PERIOD OF GUSTY WEST/DOWNSLOPE WINDS EAST
OF THE LARAMIE RANGE TO CONTRIBUTE TO COMPRESSIONAL WARMING THROUGH
EARLY AFTN. TRENDED HIGHER FOR MAX TEMPS BECAUSE OF THIS. MOISTENING
ALOFT AND STRONG PVA SUGGESTS LIGHT SNOW SHOWERS ACROSS OUR NORTHERN
AND EASTERN ZONES...SO ADDED LOW-END POPS THERE. COOLER FOR MON WITH
CYCLONIC FLOW ALOFT AND SURFACE HIGH PRESSURE ENCOMPASSING MUCH OF
THE CENTRAL AND NORTHERN ROCKIES.
.LONG TERM...(TUESDAY THROUGH FRIDAY)
ISSUED AT 253 AM MST SAT NOV 15 2014
LONG TERM LOOKS DRY FOR THE MOST PART WITH TEMPERATURES BACK TO
NEAR NORMAL FOR THIS TIME OF YEAR. WE STAY IN A NORTHWEST FLOW
THAT COULD BRING SOME QUICK HITTING SNOW SHOWERS MOSTLY TO THE
MOUNTAINS. THE MOST PROMINENT BEING THURSDAY. ECMWF ADVERTISING
THIS WITH THE GFS SOLUTION ON THE SHORTWAVE FURTHER NORTH AND EAST
OF OUR CWFA. DID KEEP SOME LOW CHANCE POPS IN THE FORECAST FOR THE
MOUNTAINS. MOST OTHER PLACES DRY THROUGH FRIDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1023 PM MST FRI NOV 14 2014
BASED 06Z TERMINAL FORECASTS OFF THE LATEST HRRR FORECAST. STARTED
LOWERING FLIGHT CONDITIONS A LITTLE EARLIER. CURRENT MOSAIC RADAR
SHOWING SNOW SHOWERS MOVING INTO CARBON COUNTY...SO KRWL SHOULD BE
COMING DOWN SOON. MORNING HOURS THROUGH 18Z WILL SEE THE MOST
WIDESPREAD IFR/LIFR CONDITIONS ACROSS SOUTHEAST WYOMING AND
NEBRASKA PANHANDLE WITH IMPROVING CONDITIONS AFTERWARDS.
&&
.FIRE WEATHER...
ISSUED AT 253 AM MST SAT NOV 15 2014
NO FIRE WEATHER CONCERNS THROUGH THIS WEEKEND. ANOTHER ARCTIC SYSTEM
WILL BRING SNOW ACROSS MOST AREAS THROUGH SATURDAY. SEVERAL INCHES
OF SNOW WILL ACCUMULATE...ESPECIALLY IN THE HIGHER ELEVATIONS OF
SOUTHERN WYOMING. THIS SNOW WILL BE FOLLOWED BY BRISK SURFACE WIND
AND COLD TEMPERATURES SUNDAY INTO SUNDAY NIGHT.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER WEATHER ADVISORY UNTIL 11 AM MST THIS MORNING FOR
WYZ101>103-112-114.
WINTER WEATHER ADVISORY UNTIL 1 PM MST THIS AFTERNOON FOR
WYZ104>106-109>111-113-115>117.
NE...WINTER WEATHER ADVISORY UNTIL 11 AM MST THIS MORNING FOR NEZ002-
095.
&&
$$
SHORT TERM...CLH
LONG TERM...GCC
AVIATION...GCC
FIRE WEATHER...CLH
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1027 PM MST FRI NOV 14 2014
.UPDATE...
ISSUED AT 934 PM MST FRI NOV 14 2014
04Z SFC ANALYSIS SHOWS COLD FRONT LOCATED FROM AROUND GUERNSEY
EAST TO BETWEEN ALLIANCE AND HEMINGFORD. NORTH OF THE FRONT
TEMPERATURES HAVE TUMBLED INTO THE TEENS...WITH 20S AND EVEN SOME
30S REMAINING SOUTH OF THE FRONT ALONG THE I-80 CORRIDOR. ALTHOUGH
AREA RADAR BEAMS ARE OVERSHOOTING MUCH OF THE SNOW...WEBCAMS
CONFIRM THAT SNOW WAS FALLING IN AREAS FROM GLENROCK EAST TO
DOUGLAS...HARRISON AND CHADRON. ALTHOUGH ACCUMULATIONS APPEAR TO
BE RELATIVELY LIGHT THUS FAR...PERHAPS UP TO AN INCH IN A FEW
AREAS. BOTH 00Z NAM/GFS HAVE A GOOD HANDLE ON THIS 1-2 INCH SNOW
BAND IN THIS AREA THRU MIDNIGHT. FRONT WILL SHIFT SOUTH OF THE
CWFA THRU THE MORNING HOURS SATURDAY...CARRYING BEST FRONTAL
FORCING WITH IT. AS SUCH...BAND OF HEAVIER SNOW WILL SPREAD SOUTH
INTO THE REMAINDER OF THE AREA BY SUNRISE OR SHORTLY THEREAFTER.
SNOW WILL BE OUT OF THE AREA BY EARLY AFTERNOON. DIDNT NEED TO
MAKE ANY CHANGES TO CURRENT HIGHLIGHT PACKAGES...ALTHOUGH DID
ADJUST SNOWFALL ACCUMS SLIGHTLY...DOWNWARD IN THE NORTH PLATTE
RIVER VALLEY AND PERHAPS SLIGHTLY LESS ELSEWHERE AS WELL. ADDED
BLOWING SNOW TO THE FORECAST AS WELL AS POST-FRONTAL NORTHERLIES
WILL GUST TO 25-30 MPH AT TIMES...ESPECIALLY TOMORROW AFTERNOON.
THE COMBINATION OF WINDS...SNOW AND SUB-ZERO WIND CHILLS WILL NOT
MAKE FOR A DAY TO SPEND MUCH TIME OUTDOORS ON SATURDAY.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 357 PM MST FRI NOV 14 2014
COLD FRONT POISED JUST TO THE NORTH OF THE FORECAST AREA THIS
AFTERNOON. UPPER LEVEL WESTERLY FLOW PARALLELING THE FRONT AND
KEEPING IT FROM MAKING MUCH PROGRESS TO THE SOUTH. SNOW SHOULD BEGIN
SPREADING EAST ACROSS CONVERSE/NIOBRARA COUNTIES BETWEEN 00Z-03Z/SAT
AND INTO DAWES AND NORTHERN SIOUX COUNTIES IN THE NEBRASKA PANHANDLE
BETWEEN 03Z-05Z/SAT. BOTH THE NAM12 AND HRRR KEEP THE SNOW CONFINED
TO THESE AREAS THROUGH 06Z/SAT. ABOUT THAT TIME...MORE ROBUST BAND
OF SNOW WILL BEGIN TO DEVELOP OVER CARBON COUNTY...ESPECIALLY ALONG
THE INTERSTATE 80 CORRIDOR AND THE MEDICINE BOW AND SIERRA MADRE
RANGES. STRONGER FRONTAL SURGE COMES AFTER ABOUT 08Z/SAT AND PUSHES
TO THE SOUTHERN BORDER OF THE FORECAST AREA BY 13Z/SAT.
BEST SNOWFALL ALONG AND EAST OF I-25 SHOULD COME WITH AND SHORTLY
BEHIND THE FRONTAL PASSAGE. PLATTE...GOSHEN...AND LARAMIE COUNTIES
ALONG WITH THE REMAINDER OF THE PANHANDLE SHOULD SEE 1 TO 3 INCH
AMOUNTS. FRONTOGENETIC FORCING DOES FAVOR SOME ENHANCED LIFT IN
LARAMIE COUNTY WHERE IMPACTS COULD STILL NECESSITATE AN UPGRADE TO A
WINTER WEATHER ADVISORY. THE EVENING SHIFT WILL NEED TO MONITOR
TRENDS FROM 00Z OUTPUT CLOSELY. IN ADDITION TO THE
SNOW...NORTHERLY WIND OF 15 TO 30 MPH WILL PREVAIL FOLLOWING COLD
FRONTAL PASSAGE. ELSEWHERE...ADVISORIES LOOK TO BE IN GOOD SHAPE
WITH FORECAST STILL ON THE CORRECT TRACK. AIRMASS SLOWLY DRIES
AFTER 18Z/SAT BUT ANY SUN WILL JUST ALLOW FOR COLD AIR
STRATOCUMULUS TO DEVELOP. OVERALL... SHOULD BE A MOSTLY CLOUDY
DAY. RAPID CLEARING WILL OCCUR AFTER SUNSET SATURDAY. GIVEN A
FRESH SNOW COVER AND A LACK OF CLOUDS...WOULD NOT BE SURPRISED TO
SEE TEMPERATURES DROP BELOW GUIDANCE. IN OUR FAVOR WOULD BE A
CONTINUING WEST WIND IN SOME AREAS THAT WILL HELP KEEP THE
BOUNDARY LAYER BETTER MIXED. THOSE AREAS LACKING WIND WILL
UNDOUBTEDLY AGAIN SEE SUB-ZERO TEMPERATURES.
NORTHERLY FLOW WILL BE REINFORCED SUNDAY AS 100KT+ JET DIVES SOUTH
OUT OF SASKATCHEWAN. HIGH-AMPLITUDE RIDGE BUILDING ALONG THE WEST
COAST WILL KEEP THE FORECAST AREA IN CYCLONIC FLOW THROUGH AT LEAST
SUNDAY NIGHT. TAIL END OF SHORTWAVE ENERGY MOVING THROUGH THE
NORTHERN PLAINS WILL BRUSH THE EASTERN TWO-THIRDS OF THE FORECAST
AREA SUNDAY. THIS WILL BRING ADDITIONAL CLOUD COVER AND ANOTHER WEAK
SHOT OF COLDER AIR. GUSTY NORTHWEST WIND 20 TO 30 MPH WILL MAKE FOR
A RAW DAY EVEN WITH TEMPERATURES REBOUNDING FROM THE COLDER AIR OF
SATURDAY AND SATURDAY NIGHT. LOW TEMPERATURES SUNDAY NIGHT WILL BE
LARGELY DEPENDENT ON HOW MUCH CLOUD COVER REMAINS...ESPECIALLY OVER
THE EASTERN PLAINS OF WYOMING AND THE PANHANDLE.
.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 357 PM MST FRI NOV 14 2014
LOOKS LIKE DRY NORTHWEST FLOW ALOFT OVER THE FORECAST AREA FOR MUCH
OF THE EXTENDED. GRADIENT IS SUCH THAT BREEZY TO WINDY CONDITIONS
WILL PERSIST EARLY IN THE EXTENDED PERIOD. SHORTWAVE RIDGE ALOFT
DEPICTED FOR WEDNESDAY AND THURSDAY WITH WARMER TEMPERATURES. CANNOT
RULE OUT A FEW SNOW SHOWERS OVER THE SNOWY AND SIERRA MADRE
RANGES...POSSIBLY MORE SO FRIDAY WITH PASSAGE OF DEEPENING MID LEVEL
TROUGH. WILL HAVE TO SEE HOW THIS TROUGH OR SHORTWAVE EVOLVES FOR
LATE THURSDAY NIGHT INTO FRIDAY...BUT NO SIGNIFICANT STORM SYSTEMS
DURING THIS PERIOD. TEMPERATURES SHOULD BE AROUND NORMAL.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1023 PM MST FRI NOV 14 2014
BASED 06Z TERMINAL FORECASTS OFF THE LATEST HRRR FORECAST. STARTED
LOWERING FLIGHT CONDITIONS A LITTLE EARLIER. CURRENT MOSAIC RADAR
SHOWING SNOW SHOWERS MOVING INTO CARBON COUNTY...SO KRWL SHOULD BE
COMING DOWN SOON. MORNING HOURS THROUGH 18Z WILL SEE THE MOST
WIDESPREAD IFR/LIFR CONDITIONS ACROSS SOUTHEAST WYOMING AND
NEBRASKA PANHANDLE WITH IMPROVING CONDITIONS AFTERWARDS.
&&
.FIRE WEATHER...
ISSUED AT 357 PM MST FRI NOV 14 2014
NO FIRE WEATHER CONCERNS THROUGH THIS WEEKEND. ANOTHER ARCTIC SYSTEM
WILL BRING SNOW ACROSS MOST AREAS THROUGH SATURDAY. SEVERAL INCHES
OF SNOW WILL ACCUMULATE...ESPECIALLY IN THE HIGHER ELEVATIONS OF
SOUTHERN WYOMING. THIS SNOW WILL BE FOLLOWED BY BRISK SURFACE WIND
AND COLD TEMPERATURES SUNDAY INTO SUNDAY NIGHT.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER WEATHER ADVISORY UNTIL 11 AM MST SATURDAY FOR WYZ101>103-
112-114.
WINTER WEATHER ADVISORY UNTIL 1 PM MST SATURDAY FOR WYZ104>106-
109>111-113-115>117.
NE...WINTER WEATHER ADVISORY UNTIL 11 AM MST SATURDAY FOR NEZ002-095.
&&
$$
UPDATE...CAH
SHORT TERM...RIW/ZF
LONG TERM...RIW/CAH
AVIATION...GCC
FIRE WEATHER...RIW/ZF
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
934 PM MST FRI NOV 14 2014
.UPDATE...
ISSUED AT 934 PM MST FRI NOV 14 2014
04Z SFC ANALYSIS SHOWS COLD FRONT LOCATED FROM AROUND GUERNSEY
EAST TO BETWEEN ALLIANCE AND HEMINGFORD. NORTH OF THE FRONT
TEMPERATURES HAVE TUMBLED INTO THE TEENS...WITH 20S AND EVEN SOME
30S REMAINING SOUTH OF THE FRONT ALONG THE I-80 CORRIDOR. ALTHOUGH
AREA RADAR BEAMS ARE OVERSHOOTING MUCH OF THE SNOW...WEBCAMS
CONFIRM THAT SNOW WAS FALLING IN AREAS FROM GLENROCK EAST TO
DOUGLAS...HARRISON AND CHADRON. ALTHOUGH ACCUMULATIONS APPEAR TO
BE RELATIVELY LIGHT THUS FAR...PERHAPS UP TO AN INCH IN A FEW
AREAS. BOTH 00Z NAM/GFS HAVE A GOOD HANDLE ON THIS 1-2 INCH SNOW
BAND IN THIS AREA THRU MIDNIGHT. FRONT WILL SHIFT SOUTH OF THE
CWFA THRU THE MORNING HOURS SATURDAY...CARRYING BEST FRONTAL
FORCING WITH IT. AS SUCH...BAND OF HEAVIER SNOW WILL SPREAD SOUTH
INTO THE REMAINDER OF THE AREA BY SUNRISE OR SHORTLY THEREAFTER.
SNOW WILL BE OUT OF THE AREA BY EARLY AFTERNOON. DIDNT NEED TO
MAKE ANY CHANGES TO CURRENT HIGHLIGHT PACKAGES...ALTHOUGH DID
ADJUST SNOWFALL ACCUMS SLIGHTLY...DOWNWARD IN THE NORTH PLATTE
RIVER VALLEY AND PERHAPS SLIGHTLY LESS ELSEWHERE AS WELL. ADDED
BLOWING SNOW TO THE FORECAST AS WELL AS POST-FRONTAL NORTHERLIES
WILL GUST TO 25-30 MPH AT TIMES...ESPECIALLY TOMORROW AFTERNOON.
THE COMBINATION OF WINDS...SNOW AND SUB-ZERO WIND CHILLS WILL NOT
MAKE FOR A DAY TO SPEND MUCH TIME OUTDOORS ON SATURDAY.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 357 PM MST FRI NOV 14 2014
COLD FRONT POISED JUST TO THE NORTH OF THE FORECAST AREA THIS
AFTERNOON. UPPER LEVEL WESTERLY FLOW PARALLELING THE FRONT AND
KEEPING IT FROM MAKING MUCH PROGRESS TO THE SOUTH. SNOW SHOULD BEGIN
SPREADING EAST ACROSS CONVERSE/NIOBRARA COUNTIES BETWEEN 00Z-03Z/SAT
AND INTO DAWES AND NORTHERN SIOUX COUNTIES IN THE NEBRASKA PANHANDLE
BETWEEN 03Z-05Z/SAT. BOTH THE NAM12 AND HRRR KEEP THE SNOW CONFINED
TO THESE AREAS THROUGH 06Z/SAT. ABOUT THAT TIME...MORE ROBUST BAND
OF SNOW WILL BEGIN TO DEVELOP OVER CARBON COUNTY...ESPECIALLY ALONG
THE INTERSTATE 80 CORRIDOR AND THE MEDICINE BOW AND SIERRA MADRE
RANGES. STRONGER FRONTAL SURGE COMES AFTER ABOUT 08Z/SAT AND PUSHES
TO THE SOUTHERN BORDER OF THE FORECAST AREA BY 13Z/SAT.
BEST SNOWFALL ALONG AND EAST OF I-25 SHOULD COME WITH AND SHORTLY
BEHIND THE FRONTAL PASSAGE. PLATTE...GOSHEN...AND LARAMIE COUNTIES
ALONG WITH THE REMAINDER OF THE PANHANDLE SHOULD SEE 1 TO 3 INCH
AMOUNTS. FRONTOGENETIC FORCING DOES FAVOR SOME ENHANCED LIFT IN
LARAMIE COUNTY WHERE IMPACTS COULD STILL NECESSITATE AN UPGRADE TO A
WINTER WEATHER ADVISORY. THE EVENING SHIFT WILL NEED TO MONITOR
TRENDS FROM 00Z OUTPUT CLOSELY. IN ADDITION TO THE
SNOW...NORTHERLY WIND OF 15 TO 30 MPH WILL PREVAIL FOLLOWING COLD
FRONTAL PASSAGE. ELSEWHERE...ADVISORIES LOOK TO BE IN GOOD SHAPE
WITH FORECAST STILL ON THE CORRECT TRACK. AIRMASS SLOWLY DRIES
AFTER 18Z/SAT BUT ANY SUN WILL JUST ALLOW FOR COLD AIR
STRATOCUMULUS TO DEVELOP. OVERALL... SHOULD BE A MOSTLY CLOUDY
DAY. RAPID CLEARING WILL OCCUR AFTER SUNSET SATURDAY. GIVEN A
FRESH SNOW COVER AND A LACK OF CLOUDS...WOULD NOT BE SURPRISED TO
SEE TEMPERATURES DROP BELOW GUIDANCE. IN OUR FAVOR WOULD BE A
CONTINUING WEST WIND IN SOME AREAS THAT WILL HELP KEEP THE
BOUNDARY LAYER BETTER MIXED. THOSE AREAS LACKING WIND WILL
UNDOUBTEDLY AGAIN SEE SUB-ZERO TEMPERATURES.
NORTHERLY FLOW WILL BE REINFORCED SUNDAY AS 100KT+ JET DIVES SOUTH
OUT OF SASKATCHEWAN. HIGH-AMPLITUDE RIDGE BUILDING ALONG THE WEST
COAST WILL KEEP THE FORECAST AREA IN CYCLONIC FLOW THROUGH AT LEAST
SUNDAY NIGHT. TAIL END OF SHORTWAVE ENERGY MOVING THROUGH THE
NORTHERN PLAINS WILL BRUSH THE EASTERN TWO-THIRDS OF THE FORECAST
AREA SUNDAY. THIS WILL BRING ADDITIONAL CLOUD COVER AND ANOTHER WEAK
SHOT OF COLDER AIR. GUSTY NORTHWEST WIND 20 TO 30 MPH WILL MAKE FOR
A RAW DAY EVEN WITH TEMPERATURES REBOUNDING FROM THE COLDER AIR OF
SATURDAY AND SATURDAY NIGHT. LOW TEMPERATURES SUNDAY NIGHT WILL BE
LARGELY DEPENDENT ON HOW MUCH CLOUD COVER REMAINS...ESPECIALLY OVER
THE EASTERN PLAINS OF WYOMING AND THE PANHANDLE.
.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 357 PM MST FRI NOV 14 2014
LOOKS LIKE DRY NORTHWEST FLOW ALOFT OVER THE FORECAST AREA FOR MUCH
OF THE EXTENDED. GRADIENT IS SUCH THAT BREEZY TO WINDY CONDITIONS
WILL PERSIST EARLY IN THE EXTENDED PERIOD. SHORTWAVE RIDGE ALOFT
DEPICTED FOR WEDNESDAY AND THURSDAY WITH WARMER TEMPERATURES. CANNOT
RULE OUT A FEW SNOW SHOWERS OVER THE SNOWY AND SIERRA MADRE
RANGES...POSSIBLY MORE SO FRIDAY WITH PASSAGE OF DEEPENING MID LEVEL
TROUGH. WILL HAVE TO SEE HOW THIS TROUGH OR SHORTWAVE EVOLVES FOR
LATE THURSDAY NIGHT INTO FRIDAY...BUT NO SIGNIFICANT STORM SYSTEMS
DURING THIS PERIOD. TEMPERATURES SHOULD BE AROUND NORMAL.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 357 PM MST FRI NOV 14 2014
VFR CONDITIONS EXPECTED AT ALL TERMINALS UNTIL ABOUT 02Z/SAT. FIRST
SURGE OF COLDER AIR WILL BEGIN TO GENERATE LIGHT SNOW GENERALLY
ALONG AND NORTH OF A KDGW-KCDR LINE BETWEEN 02Z-05Z. CONDITIONS WILL
BECOME MVFR AND EVENTUALLY IFR BY 06Z/SAT AT KCDR. KAIA AND KBFF
WILL BEGIN TO GET IN ON THE ACTION WITH MVFR EXPECTED AROUND 06Z/SAT
AS THE AREA OF LIGHT SNOW SAGS SLOWLY SOUTH. ABOUT THE SAME TIME...
APPEARS THAT A BETTER BAND OF SNOW WILL EXTEND EAST INTO CARBON
COUNTY AND IMPACT KRWL BY 08Z/SAT. A SECOND WAVE OF SNOW WILL THEN
DEVELOP AS A STRONGER FRONTAL SURGE TRAVERSES THE FORECAST AREA FROM
NORTH TO SOUTH FROM 08Z TO 13/SAT. GUSTY NORTHERLY WIND OF 15-30KTS
WILL ACCOMPANY AND FOLLOW FRONTAL PASSAGE. IFR AND LIFR CONDITIONS
WILL BE WIDESPREAD WITH THE HEAVIEST SNOWFALL LIKELY TO OCCUR
BETWEEN ABOUT 10Z-15Z/SAT. DRIER CONDITIONS SHOULD BEGIN TO PUSH
ACROSS THE FORECAST AREA FROM NORTH-TO-SOUTH BETWEEN 15Z-20Z/SAT.
THERE SHOULD BE ENOUGH COLD AIR ALOFT THAT ANY PARTIAL CLEARING WILL
ALLOW FOR STRATOCUMULUS TO FORM...ALTHOUGH CONDITIONS SHOULD BE VFR
AFTER ABOUT 19Z/SAT. MOUNTAIN OBSCURATIONS WILL BE WIDESPREAD FROM
SHORTLY AFTER 00Z/SAT UNTIL ABOUT 18Z/SAT. MOUNTAIN TOP OBSCURATIONS
WILL CONTINUE AFTER THAT TIME UNTIL SUNSET LATE SATURDAY
AFTERNOON.
&&
.FIRE WEATHER...
ISSUED AT 357 PM MST FRI NOV 14 2014
NO FIRE WEATHER CONCERNS THROUGH THIS WEEKEND. ANOTHER ARCTIC SYSTEM
WILL BRING SNOW ACROSS MOST AREAS THROUGH SATURDAY. SEVERAL INCHES
OF SNOW WILL ACCUMULATE...ESPECIALLY IN THE HIGHER ELEVATIONS OF
SOUTHERN WYOMING. THIS SNOW WILL BE FOLLOWED BY BRISK SURFACE WIND
AND COLD TEMPERATURES SUNDAY INTO SUNDAY NIGHT.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER WEATHER ADVISORY UNTIL 11 AM MST SATURDAY FOR WYZ101>103-
112-114.
WINTER WEATHER ADVISORY UNTIL 1 PM MST SATURDAY FOR WYZ104>106-
109>111-113-115>117.
NE...WINTER WEATHER ADVISORY UNTIL 11 AM MST SATURDAY FOR NEZ002-095.
&&
$$
UPDATE...CAH
SHORT TERM...RIW/ZF
LONG TERM...RIW/CAH
AVIATION...RIW/CAH
FIRE WEATHER...RIW/ZF
AREA FORECAST DISCUSSION
NWS PUEBLO CO
444 AM MST SAT NOV 15 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 412 AM MST SAT NOV 15 2014
...MORE SNOW AND ARCTIC AIR ON THE WAY...
CURRENTLY...
THE LEADING EDGE OF THE NEXT ARCTIC INTRUSION WAS ALONG THE CO/WY
BORDER AND IT WAS HEADING SOUTH. CLOSER TO HOME...TEMPERATURES AT 3
AM VARIED CONSIDERABLY ACROSS THE PLAINS...AS ELEVATIONS GENERALLY
ABOVE 6000 FEET WERE IN THE RELATIVELY WARMER AIR (30S AND 40S)
WHILE AREAS BELOW 6000 WERE IN THE TEENS AND 20S. IN THE MTNS AND
VALLEYS...IT WAS RELATIVELY WARM WITH TEMPS IN THE 20S AND 30S.
RADAR...OBS AND WEB CAMS INDICATED THAT SNOW STILL OCCURRING OVER
THE CONTDVD.
TODAY...
WEATHER WILL BE QUITE ACTIVE DURING THE NEXT 24. HRRR INDICATES THAT
THE LEADING EDGE OF THE ARCTIC AIR WILL MOVE INTO EL PASO COUNTY
AROUND 9-10 AM AND WILL PROGRESS SOUTH...REACHING THE NEW MEXICO
BORDER BY 3 PM. LIKEWISE...MAX TEMPS TODAY WILL LIKELY OCCUR THIS
MORNING ACROSS THE PIKES PEAK REGION AND MIDDAY ACROSS THE REST OF
THE REGION. TEMPS WILL QUICKLY FALL AFTER THE ARCTIC FRONT GOES BY.
AS FOR PRECIP...IN THE MTNS...STEADY SNOW...SOME HEAVY...WILL
CONTINUE ACROSS THE CENTRAL MTNS ALL DAY TODAY. SNOW ACROSS THE SAN
JUANS WILL DECREASE LATER THIS MORNING BUT WILL RAMP UP ONCE AGAIN
BY MID AFTERNOON.
PRECIP ON THE PLAINS WILL GENERALLY DEVELOP ACROSS THE PIKES PEAK
REGION SHORTLY AFTER NOON AND WILL PICK UP AS THE AFTERNOON
PROGRESSES. STEADY SNOW WILL LIKELY BE ONGOING BY LATE AFTERNOON
ACROSS EL PASO COUNTY AND TRAVEL WILL ONCE AGAIN BECOME DIFFICULT
ACROSS THIS REGION. WINDS WILL LIKELY BE A BIT GUSTY SO AREAS OF
BLOWING SNOW WILL OCCUR.
BY LATE AFTERNOON THE SNOW WILL DEVELOP FARTHER SOUTH DOWN THE I-25
CORRIDOR AND EASTERN MTN REGION. OTHERWISE...THE REST OF THE PLAINS
WILL LIKELY REMAIN DRY.
TONIGHT...
MAIN CONCERN DURING THIS PERIOD IS THE SPANISH PEAKS/RATON MESA/WET
MTNS REGION AS ALL GUIDANCE IS SHOWING PRETTY HEALTHY QPF BULLSEYES
OVER THIS REGION. FOR NOW I HAVE ISSUED A WINTER WEATHER ADVISORY
FOR THIS REGION WITH THE AREA LIKELY RECEIVING 3-6 INCHES OF SNOW AT
THE LOWER ELEVATIONS OF LAS ANIMAS AND HUERFANO COUNTIES WHILE HIGHER
ELEVATIONS WILL LIKELY RECEIVE 4 TO 10 INCHES OF SNOW. IT IS
POSSIBLE THAT THESE VALUES MAY BE ON THE LOW SIDE...ESPECIALLY IF
GUIDANCE DOES VERIFY. WILL ALLOW LATER SHIFT TO REANALYZE AND
UPGRADE TO WARNING STATUS IF LATER SIMULATIONS SHOW LARGE QPF VALUES
OVER AFOREMENTIONED REGION.
FOR THE REST OF THE PLAINS...EL PASO COUNTY SHOULD GENERALLY RECEIVE
ABOUT 2-4" OF SNOW WITH THIS EVENT WITH 2-6 IN TELLER COUNTY AND
PIKES PEAK. PUEBLO/FREMONT COUNTIES WILL LIKELY RECEIVE ANYWHERE
FROM BETWEEN 2 AND 5 INCHES. OVER THE FAR EAST PLAINS...1 TO 2
INCHES WILL BE POSSIBLE.
THE MOUNTAINS WILL CONTINUE TO SEE SNOW...HOWEVER THE SNOW WILL END
FROM S TO N ACROSS THE C MTNS LATER TONIGHT. OVERALL ANOTHER 6 TO
12 INCHES OF SNOW IS LIKELY OVER THE CONTDVD REGION
TEMPS TONIGHT WILL BE COLD ONCE AGAIN ACROSS THE ENTIRE REGION.
SINGLE DIGITS WILL OCCUR ACROSS NEARLY ALL OF THE REGION EXCEPT
TEENS MAINLY IN THE SAN LUIS VALLEY. /HODANISH
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 412 AM MST SAT NOV 15 2014
...COLD SUNDAY THEN GRADUAL WARMING...
SNOW WILL LINGER ALONG THE SOUTHERN BORDER AREAS EARLY
SUNDAY...BUT SHOULD MOSTLY END BY NOON AS PROGRESSIVE
SHORTWAVE MOVES ON THROUGH. NEW SHOT OF ARCTIC AIR WILL
BRING ONE MORE REALLY COLD DAY SUNDAY BUT THEN THINGS WILL
START TO WARM UP AND DRY OUT FOR MOST OF THE UPCOMING WEEK.
THE WARM UP MAY START A LITTLE SLOW ON MONDAY AS SNOW COVER AND
LIGHT PRESSURE GRADIENTS WILL TEND TO KEEP SURFACE INVERSIONS IN
PLACE THROUGH THE DAY. BY TUESDAY...IT LOOKS LIKE WE SHOULD SEE A
LITTLE BETTER MIXING AS DOWNSLOPE PRESSURE GRADIENTS DEVELOP. THIS
SHOULD HELP BRING CHINOOK BREEZES OFF THE MOUNTAINS TO START
WARMING THE AIR.
COULD BE A LITTLE SET BACK WEDNESDAY AS THE MODELS ARE SHOWING A
WEAK SURFACE HIGH DROPPING THROUGH THE PLAINS THIS DAY. THIS COULD
REESTABLISH INVERSIONS IF THERE IS ENOUGH COOLING WITH THE HIGH
AND IF THERE IS ANY SNOW COVER REMAINING.
THURSDAY AND ESPECIALLY FRIDAY...IT LOOKS LIKE SOME WEAK ENERGY
FROM THE PACIFIC WILL START MOVING BACK INTO THE REGION. THIS
ENERGY COULD SPREAD SOME SNOW SHOWERS INTO THE CONTINENTAL DIVIDE
THURSDAY...AND EAST TO THE REST OF THE MOUNTAINS AND PIKES PEAK
REGION ON FRIDAY. THE APPROACHING ENERGY DOESN`T LOOK STRONG AT
THIS POINT SO FORECAST CONFIDENCE IS LOW AT THIS TIME. TEMPERATURES
WILL LIKELY REMAIN MILD THURSDAY...BUT THEN START TO COOL ON
FRIDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 412 AM MST SAT NOV 15 2014
KCOS...ARCTIC FRONT WILL CROSS KCOS AOA NOONTIME...18-19Z. WINDS
WILL SHIFT TO NORTH THAN NORTH-NORTHEAST AND BECOME GUSTY. COULD SEE
SOME SNOW SHOWERS BY MID AFTERNOON BUT EXPECT BRUNT OF IT WILL OCCUR
MORE TOWARDS SUNSET. LIFR CONDITIONS WILL BE POSSIBLE/LIKELY BETWEEN
00Z-09Z AS STEADY SNOW IS EXPECTED.
KPUB...ARCTIC FRONT WILL CROSS KPUB AOA 19-20Z WITH WINDS QUICKLY
SHIFTING TO THE NORTHEAST AND THEN EAST. PRECIP WILL LIKELY DEVELOP
AFTER SUNSET AND THERE IS A HIGH PROBABILITY THAT IT WILL SNOW...AND
IT IS EXPECTED TO ACCUMULATE TO 2-4 INCHES. LIFR CONDITIONS LIKELY
ONCE SNOW STARTS. IT WILL LAST THROUGH THE NIGHT ENDING AROUND
SUNRISE.
KALS...LOW CIGS THIS MORNING SHOULD BREAK UP ABOUT 1-2HRS AFTER
SUNRISE AS WEST WINDS INCREASE. VFR EXPECTED THROUGH THE REST OF THE
DAY WITH PRECIP DEVELOPING AFTER MIDNIGHT. SNOW WILL LIKELY
ACCUMULATE AT KALS WITH 1-2" ANTICIPATED. CIGS LIKELY WILL GO LIFR
AFTER MIDNIGHT.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 5 PM THIS AFTERNOON TO 9 AM MST
SUNDAY FOR COZ072>075-079-080-087-088.
WINTER STORM WARNING UNTIL 5 AM MST SUNDAY FOR COZ058-060-066-
068.
WINTER WEATHER ADVISORY UNTIL 5 AM MST EARLY THIS MORNING FOR
COZ073-075.
&&
$$
SHORT TERM...HODANISH
LONG TERM...LW
AVIATION...HODANISH
AREA FORECAST DISCUSSION
NWS DES MOINES IA
539 AM CST SAT NOV 15 2014
...UPDATED AVIATION DISCUSSION...
.SHORT TERM /TODAY/...
ISSUED AT 303 AM CST SAT NOV 15 2014
NO MAJOR CHANGES WITH ONGOING FORECAST FOR THE FIRST
SIGNIFICANT SNOWFALL OF THE SEASON AS MODELS REMAIN IN GOOD
AGREEMENT WITH EXPECTED SNOW TODAY. USED A BLEND OF THE
HRRR/HOPWRF FOR TIMING OF PRECIP AND NAM/ECMWF TEMPS.
BROAD ISENTROPIC LIFT AND DECENT MOISTURE TRANSPORT DEVELOP OVER
WESTERN TO NORTHWEST IOWA THIS MORNING AND QUICKLY BLOSSOMS ACROSS
THE REMAINDER OF THE STATE THIS AFTERNOON. ONE MINOR CHANGE WAS
START THE SNOW A LITTLE SOONER THIS MORNING OVER THE WEST TO
NORTHWEST AS SNOW ALREADY DEVELOPING ALOFT AND SNOW SHOULD START
REACHING THE SURFACE BETWEEN 12-14Z THIS MORNING. THE 15.03Z
HOPWRF AND 15.05Z HRRR HAVE SNOW MOVING INTO THE WESTERN EDGES OF
THE FORECAST AREA BETWEEN 13-15Z. THE FORECAST SOUNDINGS ACROSS
NORTHERN IOWA BECOME COMPLETELY SATURATED BY 17-18Z TODAY AND THE
STRONGER OMEGA IS JUST AT THE TOP EDGE OF THE DENDRITIC LAYER BUT
ENOUGH OVERLAP TO SEE SOME DECENT FLAKES...AND THUS SLIGHTLY
HIGHER SNOW ACCUMULATION THIS AFTERNOON OVER NORTHERN IOWA. RAP IS
A BIT LESS WITH THE FORCING THAN THE NAM/GFS AND HAS SLIGHTLY
LOWER SNOW AMOUNTS GOING...BUT STILL DEPICTS ENOUGH SNOW TO
WARRANT ADVISORY. FURTHER SOUTH...SOUNDINGS NOT TOO DISSIMILAR
THAN NORTHERN IOWA...WITH THE MAIN DIFFERENCE BEING JUST SLIGHTLY
LESSER FORCING WITHIN THE DENDRITIC LAYER. THIS RESULTING IN LESS
SNOW AMOUNTS OVER THE SOUTHERN TWO-THIRDS OF THE FORECAST AREA.
LEANED TOWARD A BLEND OF THE WARMER NAM/ECMWF FOR TEMPERATURES
TODAY. THIS RESULTED IN SNOW RATIOS AROUND 17:1 TO 18:1 OVER
NORTHERN IOWA AND 15:1 TO 16:1 ACROSS THE SOUTH...BASED ON 925M
TO 700MB THICKNESS. HAVE 100 POPS GOING MUCH OF THE AFTERNOON WITH
HIGH CONFIDENCE ALL OF CENTRAL IOWA WILL BE SNOWING BY OR SHORTLY
PAST 18Z. VERY LITTLE WIND TODAY BUT WITH THE FLUFFY SNOW TYPE
EXPECTED AND AT TIMES FALLING MODERATELY...THIS SHOULD BE ENOUGH
TO CAUSE SOME VISIBILITY RESTRICTION WITH A 6-9 KNOT WIND.
.LONG TERM /TONIGHT THROUGH FRIDAY/...
ISSUED AT 303 AM CST SAT NOV 15 2014
ACTIVE WEATHER WILL CONTINUE THROUGH THE WEEKEND AND EARLY NEXT
WEEK FOLLOWING TONIGHTS SYSTEM...ANOTHER INTENSE UPPER LEVEL LOW
WILL DROP SOUTH INTO THE NORTHERN GREAT LAKES SUNDAY NIGHT AND
MONDAY MORNING. TONIGHT...SYSTEM EXITING THE AREA TO THE EAST
DURING THE EVENING HOURS. BEST FORCING ALONG H500 AND SFC TROUGH
NEAR 00Z FOCUSING ON H700 BOUNDARY ACROSS NORTHERN IOWA. THROUGH
06Z THIS H700 BOUNDARY PUSHES EAST WITH TROUGH RESULTING IN
LESSENING FORCING WEST OF I35 DURING THE LATE EVENING. BY 12Z BEST
FORCING EAST OF THE AREA WITH SOME RESIDUAL LIGHT SNOW/FLURRIES
OVER THE NORTHEAST ENDING QUICKLY WITH CLOUDS DEPARTING IN THE
MORNING SUNDAY. SNOW RATIOS OF 18 TO 20:1 AND EXPECTED QPF AMOUNT
YIELD SNOWFALL AMOUNTS OF UP TO ANOTHER 1.5 INCHES TONIGHT DURING
THE EVENING AND OVERNIGHT HOURS. FORTUNATELY THE WINDS WILL BE
LIGHT DURING THE EVENT...SO BLOWING SNOW WILL NOT BE AN ISSUE
TONIGHT. WITH CLEARING BY MORNING...LOWS WILL QUICKLY FALL
NORTHWEST AND WEST INTO THE SINGLE DIGITS WITH TEENS I35 EAST.
SUNDAY WILL INITIALLY SEE SOME SUNSHINE BETWEEN WAVES BUT CLOUDS
WILL INCREASE WEST DURING THE AFTERNOON. WITH H850 TEMPS IN THE
-10C TO -12C RANGE AND WESTERLY WINDS...TEMPERATURES WILL BE
TOLERABLE IN THE MID 20S OVER MOST OF THE AREA. AN APPROACHING
COLD FRONT WILL SPREAD CLOUDS ACROSS THE REGION THROUGH EARLY
EVENING. THE SECOND STRONG H500 LOW WILL FORCE A BULGE OF COLD AIR
QUICKLY SOUTHEAST INTO WESTERN IOWA SUNDAY EVENING WITH RATHER
STRONG COLD AIR ADVECTION AND INCREASING WINDS ALOFT. BY 12Z H850
TEMPS WILL HAVE FALLEN ANOTHER 8 TO 10C WITH READINGS FROM -16C TO
-20C. THROUGH THE DAY MONDAY CLOUD COVER WILL OVERTAKE THE AREA
WITH H850 TEMPS SETTLING TOWARD -18C TO -20C REGION WIDE. MODELS
HAVE BEEN CONSISTENT WITH STEEPENING LAPSE RATES NEAR 15Z AND
STRONG MIXING THROUGH THE DAY...POTENTIAL FOR SNOW SHOWERS ACROSS
THE NORTHEAST WITH FLURRIES CENTRAL AND SOUTH. ALL IN ALL...MONDAY
IS LOOKING RATHER UNPLEASANT. POTENTIAL FOR 15 TO 25 MPH WINDS
WITH GUSTS TO NEAR 35 MPH AT TIMES. THIS WILL CAUSE PATCHY TO
AREAS BLOWING SNOW OVER MUCH OF THE NORTHEAST HALF OF THE AREA
WITH REDUCTIONS TO VISIBILITY. HEADLINES MAY BE NEEDED AGAIN ON
MONDAY FOR THE COMBINATION OF WIND...BLOWING SNOW...AND COLD. HAVE
EXPANDED THE POTENTIAL FOR LIGHT PRECIP AND BLOWING SNOW MONDAY
ACROSS THE AREA. HIGHS WILL RECOVER LITTLE FROM FRIGID MORNING
LOWS IN THE SINGLE DIGITS TO LOWER TEENS. BY AFTERNOON HIGHS NORTH
WILL REACH THE LOWER TEENS TO THE LOWER 20S IN THE SOUTHEAST. TO
TOP OFF THE WONDERFUL DAY...MINIMUM RECORD HIGHS LOOK LIKELY TO BE
SET AT MANY LOCATIONS...ONE WHICH HAS NOT BEEN SEEN SINCE THE
1890S AND MANY SINCE THE 1950S. IN FACT...OUR HIGHS MONDAY WOULD
STILL BE ABOUT 10 TO 15 DEGREES BELOW OUR COLDEST AVERAGE HIGHS
FOR THE NORMALLY COLDEST WINTER DAY OF THE YEAR...OR ABOUT 30
DEGREES BELOW OUR NORMAL FOR 11/17. WE HAVENT HAD HIGHS THIS COLD
SINCE EARLY MARCH OF 2014. TUESDAY WILL BEGIN QUITE COLD WITH A
RIDGE JUST EDGING INTO THE AREA BUT WARM BY AFTERNOON. QUICKLY
ANOTHER CLIPPER OVER THE NORTHERN PLAINS WILL MODERATE THE AIRMASS
WITH BRISK WEST WINDS DEVELOPING DURING THE DAY. TEMPS WILL RISE
INTO THE 20S. ANOTHER ARCTIC FRONT WILL DROP SOUTH INTO THE AREA
TUESDAY NIGHT BUT THE AIRMASS WILL NOT BE QUITE AS COLD AS THE
PREVIOUS. THE REMAINDER OF THE WEEK FEATURES A SERIES OF ARCTIC
SHORT WAVES ROTATING AROUND THE HUDSON BAY PARENT H500
LOW...PULLING ADDITIONAL COLD AIR TOWARD THE GREAT PLAINS. NEXT
WEEK WILL FEATURE DAYS WITH CLOUD COVER MIXED WITH SOME SUNSHINE
AND CHILLY READINGS. FORTUNATELY BY LATE IN THE EXTENDED...TOWARD
SATURDAY THE CROSS POLAR FLOW CUTS OFF...THE H500 RIDGE ACROSS THE
WEST COAST BREAKS DOWN AND MORE ZONAL FLOW RESULTS OVER THE
ROCKIES. THIS WILL CAUSE CHINOOK COMPRESSIONAL HEATING OVER THE
PLAINS AND MODERATE HIGHS TO ABOVE FREEZING. FROM WEDNESDAY
THROUGH FRIDAY HIGHS WILL APPROACH THE 30 DEGREE MARK WITH LOWS
MODERATING INTO THE TEENS OVER THE AREA. LITTLE PRECIPITATION IS
EXPECTED FOR MUCH OF THE PERIOD NEXT WEEK.
&&
.AVIATION...15/12Z
ISSUED AT 536 AM CST SAT NOV 15 2014
MVFR CONDITIONS WILL QUICKLY MOVE IN WITH THE SWATH OF SNOW LATE
THIS MORNING CONTINUE THROUGH THE AFTERNOON HOURS. HAVE IFR
CONDITIONS MENTIONED THIS AFTERNOON DURING THE HIGHER SNOWFALL
RATES ANTICIPATED. HIGHER CONFIDENCE TO MENTION IFR CIGS THIS
AFTERNOON AND KEPT MVFR CIGS THROUGH THE END OF THE TAF PERIOD.
SNOW SHOULD END BY 06Z TONIGHT...IF NOT SOONER FROM WEST TO EAST
HELPING TO IMPROVE VISIBILITY.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 9 AM THIS MORNING TO MIDNIGHT CST
TONIGHT FOR ADAIR-ADAMS-APPANOOSE-AUDUBON-BLACK HAWK-BOONE-
BREMER-BUTLER-CALHOUN-CARROLL-CASS-CERRO GORDO-CLARKE-CRAWFORD-
DALLAS-DAVIS-DECATUR-EMMET-FRANKLIN-GREENE-GRUNDY-GUTHRIE-
HAMILTON-HANCOCK-HARDIN-HUMBOLDT-JASPER-KOSSUTH-LUCAS-MADISON-
MAHASKA-MARION-MARSHALL-MONROE-PALO ALTO-POCAHONTAS-POLK-
POWESHIEK-RINGGOLD-SAC-STORY-TAMA-TAYLOR-UNION-WAPELLO-WARREN-
WAYNE-WEBSTER-WINNEBAGO-WORTH-WRIGHT.
&&
$$
SHORT TERM...PODRAZIK
LONG TERM...REV
AVIATION...PODRAZIK
AREA FORECAST DISCUSSION
NWS GOODLAND KS
447 AM MST SAT NOV 15 2014
.SHORT TERM...(TODAY THROUGH MONDAY NIGHT)
ISSUED AT 404 AM MST SAT NOV 15 2014
MAIN FORECAST CONCERN WILL BE WINTER WEATHER EVENT OCCURRING
THROUGH TONIGHT. SATELLITE CONTINUING TO SHOW AN AMPLIFIED PATTERN
FROM THE EASTERN PACIFIC INTO EASTERN NORTH AMERICA. CURRENTLY
NEARLY ZONAL FLOW OVER OUR AREA WITH MULTIPLE SMALL SCALE WAVES
EMBEDDED WITHIN THAT FLOW. STRONG...COLD AND RATHER COMPLEX UPPER
TROUGH IS MOVING THROUGH THE NORTH CENTRAL OF THE COUNTRY.
SATELLITE ALSO SHOWING DRY MID LEVEL AIR MASS IN PLACE AHEAD OF
INCOMING NORTHERN TROUGH. ANOTHER STRONG COLD FRONT IS APPROACHING
FROM THE NORTH.
AT JET LEVEL...MODELS LOOKED LIKE THEY INITIALIZED FINE. AT MID
LEVELS...THE GFS WAS DOING A LITTLE BETTER THAN THE ECMWF AND
CANADIAN. THE SREF WAS DOING THE BEST AT THE SURFACE. ALL THE
MODELS WERE OKAY ON THE LOW LEVEL THERMAL FIELD.
TODAY/TONIGHT...THE DAY STARTS OUT WITH AREA IN SUBSIDENCE FROM
DEPARTING JET. AFTER THIS MODELS DISAGREE WHERE THE MAIN JET
ENERGY WILL BE THROUGH THE REST OF THE PERIOD. BY 18Z IT LOOKS
LIKE A LEFT FRONT QUADRANT WILL BEGIN AFFECTING THE AREA. BY LATE
IN THE AFTERNOON INTO THE EVENING...THERE MAY BE A RIGHT REAR
QUADRANT ACROSS THE SOUTHEASTERN PORTION OF THE AREA. AFTER THAT
THE JET IS WELL SOUTH.
CURRENTLY INITIAL SHORTWAVE TROUGH IS MOVING THROUGH AND PRODUCING
LIGHT SNOW OVER SOUTHERN AND EASTERN SECTIONS. MODELS HAVE A GOOD
HANDLE ON THIS INITIAL SHORTWAVE TROUGH. CURRENT RADAR SHOWS THAT
THE MOST INTENSE SNOWFALL IS TO THE SOUTH OF AREA AND MOVING
THROUGH RATHER QUICKLY. ALL NIGHT THE HRRR HAS BEEN CATCHING THE
CURRENT RADAR TRENDS EXTREMELY WELL AND IT ALSO MATCHES UP WELL
WITH THE ABOVE MENTIONED MID AND UPPER LEVEL LIFT. OTHER OUTPUT IS
TOO FAR NORTH WITH THE PRECIPITATION SHIELD. SO WILL LEAN HEAVILY
ON THE HRRR FOR PRECIPITATION EARLY ON AND THEN TREND MORE TOWARD
THE CANADIAN/ECMWF AFTER THAT.
SO LITTLE TO NO SNOW FALL WILL END UP FALLING OVER THE WESTERN
HALF TO TWO THIRDS THIS MORNING WITH MOST OF THE SNOW OCCURRING IN
THE EASTERN SIX COUNTIES THROUGH MID MORNING. UPSTREAM SATELLITE
IS SHOWING A CLEARING TREND BEHIND THIS EXITING SHORTWAVE AND A
DRY AIR MASS IN ADVANCE OF THE NEXT SHORTWAVE TROUGH. AFTER THE
SNOW ENDS THIS MORNING...THE NEXT BATCH OF LIGHT SNOW WILL DEVELOP
TO OUR NORTH AND NORTHWEST BY LATE IN THE MORNING TO EARLY
AFTERNOON. THIS AREA THEN MOVES ACROSS THE AREA THROUGH THE REST
OF THE NIGHT WITH THE MOST SNOWFALL OCCURRING BEFORE MIDNIGHT. IT
IS POSSIBLE THAT SOME LOCATIONS MAY NOT SEE ANY SNOW UNTIL LATER
THIS AFTERNOON TO EARLY THIS EVENING.
MODELS...ESPECIALLY THE GFS...TEND TO BE TOO DEEP WITH THE
MOISTURE AND THEREFORE OVERPRODUCES PRECIPITATION. THE DRIER AIR
MASS UPSTREAM MAKES SENSE SINCE MOISTURE IN THE WESTERLY FLOW
ALOFT IS GETTING WRUNG BY THE HIGHER TERRAIN OVER COLORADO. SO PER
THE REASONING GIVEN ABOVE...SNOWFALL AMOUNTS WILL BE MUCH LIGHTER
THAN PREVIOUSLY EXPECTED WITH TOTAL AMOUNTS NOW ANTICIPATED TO BE
AROUND AN INCH OR LESS. IT IS ALSO POSSIBLE THAT WHEN THE COLD
FRONT MOVES THROUGH LATER TODAY...THAT LITTLE IF ANY SNOW WILL BE
ON THE GROUND. ALSO CONSIDERING WHAT LITTLE SNOW HAS ALREADY
FALLEN AND THAT THERE WILL BE A SIGNIFICANT LULL BEFORE THE NEXT
SNOWFALL STARTS...HAVE DECIDED TO CANCEL THE WINTER WEATHER
ADVISORY. IF SNOWFALL ENDS UP BEING WORSE THAN CURRENTLY
EXPECTED...THEN A MORE SHORT TERM ADVISORY CAN BE ISSUED TO HANDLE
THAT SINCE NOTHING IS GOING ON AT THIS TIME.
NOW FOR TEMPERATURES. JUST LIKE LAST NIGHT...MODELS ARE TOO COOL
WITH THE CURRENT TEMPERATURES DUE TO CLOUD COVER AND CONTINUED
WARM AIR ADVECTION. FRONT IS ALSO EXPECTED TO ARRIVE LATER AND
WILL NOT MOVE THROUGH THE EASTERN PORTION OF THE AREA UNTIL THIS
AFTERNOON. THERE ALSO MAY BE ENOUGH BREAKS IN THE CLOUD COVER TO
ALLOW SOME SUNSHINE TO OCCUR. A LOT OF THE OUTPUT IS SAYING
WARMER AND TRENDED IN THAT DIRECTION.
SUNDAY/SUNDAY NIGHT...DRY CONDITIONS EXPECTED THROUGH THE PERIOD.
SHOULD SEE A DECENT AMOUNT OF SUN WITH WINDS BEING MOSTLY FROM A
DOWNSLOPE DIRECTION. MODELS ARE SHOW TEMPERATURES WARMER THAN
YESTERDAY. MODELS HAVE HAD A RECENT COOL BIAS AS WELL. SO WENT
NEAR THE WARMER GUIDANCE.
MONDAY/MONDAY NIGHT...STRONG UPPER SYSTEM DIGS INTO THE NORTH
CENTRAL PORTION OF THE COUNTRY JUST BEFORE AND DURING THIS PERIOD.
THIS PUSHES ANOTHER COLD FRONT THROUGH THE AREA AND SHOULD MAKE
FOR COOLER TEMPERATURES COMPARED TO SUNDAY MAXES. HOWEVER...THERE
IS A BIG DIFFERENCE IN THE AMOUNT OF COOLING INDICATED BY THE
MODELS. DID NOT GO WITH THE COLDEST GUIDANCE BUT TRENDED IN THE
COLDER DIRECTION.
.LONG TERM...(TUESDAY THROUGH FRIDAY)
ISSUED AT 404 AM MST SAT NOV 15 2014
COMPARING TONIGHTS MODELS RUN TO LAST NIGHTS THE LONG WAVE RIDGE
OVER THE WEST COAST OF THE UNITED STATES WILL STILL MOVE EAST AND BE
LOCATED OVER THE ROCKIES BY FRIDAY. HOWEVER... UNLIKE LAST NIGHTS
RUN... WHERE THE RIDGE LOOKED LIKE IT WOULD FLATTEN... IT NOW
SEEMS IT WILL MAINTAIN ITS AMPLITUDE. THIS WILL PRODUCE A
PREDOMINATELY NORTHWESTERN UPPER LEVEL FLOW OVER THE TRI-STATE
AREA DURING THE EXTENDED.
YESTERDAYS QUESTION WAS WHEN WILL THE NEXT FRONT PASS OVER THE AREA.
TONIGHTS RUN OF THE GFS... NAVGEM AND ECMWF ARE IN BETTER AGREEMENT
ON THIS FRONT COMPARED TO LAST NIGHTS RUN. THEY ALL HAVE THE FRONT
PASSING OVER THE AREA ON THE 19TH BETWEEN 00Z AND 06Z. THEY ALSO
SHOW THIS SYSTEM TO BE A DRY ONE AND WILL HAVE LITTLE TO NO EFFECT
ON THE TEMPERATURES. IT DOES SHOW A SHIFT IN THE WINDS FOLLOWED BY
LIGHT WINDS AS HIGH PRESSURE BUILDS IN BEHIND IT FOR THE REST OF THE
EXTENDED.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 440 AM MST SAT NOV 15 2014
MODELS ARE HAVING A HARD TIME RESOLVING ONGOING CONDITIONS. THEY
ARE TENDING TO OVERDUE LOW LEVEL CLOUD COVER AND PRECIPITATION.
WILL BE GOING WITH PERSISTENCE/CURRENT CONDITIONS AND THE BEST
MESOSCALE GUIDANCE FOR THE BEGINNING OF THIS FORECAST. FIRST
SHORTWAVE AND ASSOCIATED SNOWFALL HAS MOVED TO THE EAST OF BOTH
TAF SITES. SO WILL HAVE VFR CONDITIONS AND NO SNOWFALL AT BOTH
SITES UNTIL THIS AFTERNOON WHEN NEXT SHORTWAVE TROUGH MOVES IN.
MVFR CEILINGS WILL BE POSSIBLE AT BOTH SITES THIS AFTERNOON INTO
EARLY THIS EVENING. AFTER THAT VFR CONDITIONS WILL RETURN TO BOTH
SITES. A COLD FRONT WILL MOVE THROUGH LATE THIS MORNING INTO
EARLY THIS AFTERNOON AND WILL PRODUCE SUSTAINED WINDS OF 15 TO 20
KNOTS WITH GUSTS GETTING CLOSE TO 30 KNOTS. GUSTS WILL END EARLY
THIS EVENING.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...BULLER
LONG TERM...BDW/BULLER
AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS TOPEKA KS
523 AM CST Sat Nov 15 2014
...AVIATION UPDATE...
.SHORT TERM...(Today and Tonight)
Issued at 223 AM CST SAT NOV 15 2014
09Z Water vapor and profiler data show the lead shortwave beginning
to come out of the Rockies and into western KS. Regional radars
show a band of precip preceding the wave now moving into central KS.
So the forecast appears to be on track, kind of.
Models continue to show a progressive wave moving across the area
today and the best forcing and lift is expected to overspread north
central KS during the next 3 to 6 hours. By noon or shortly after,
the forcing diminishes and models show the vertical motion shifting
out of the area. There still does not appear to be much of a surface
reflection with the short wave that could enhance mesoscale forcing
either. There atmosphere does appear to be weakly unstable with some
conditional symmetric instability and even hints of upright
instability which could allow for a brief intensification to the
snowfall. There have been some lightning strikes over the central
Rockies with the wave. In general everything points to lower snow
amounts today due to no sustained forcing mechanism to maintain
precipitation. And given the track of the wave, which fits well with
the latest guidance, north central KS is more likely to see 1 to 3
inches while east central KS might be lucky to pick up an inch. Will
not make any changes to the advisory at this time. The biggest
impact could be a brief period of heavy snow in the convective
elements that restricts visibilities and quickly brings an inch or
so of snow.
Have bumped up highs today to around the freezing mark. While it is
not real strong, there is persistent low level warm air advection
with the southeast winds of 5 to 10 mph. If snowfall ends early in
the day and the clouds thin, highs could be a degree or two warmer.
Am not real concerned about mixed precip today as forecast soundings
maintain temps below freezing aloft. Its only at the surface where
temps warm above freezing and this is likely to happen once the
snowfall exits to the east and north. About the only concern I have
for a different precip type other than snow is for the potential of
light drizzle this afternoon. Low levels stay saturated with some
weak isentropic lift in the cloud. If drizzle (or freezing drizzle
depending on temps) were to happen, think it would occur after the
area of snow has ended due to a lose of forcing and deep vertical
motion.
For tonight, there remains some forcing as a more amplified wave
swings across NEB driving a cold front through the area. However by
this time models have a hard time keeping the column saturated. Have
kept some small chances going to account for the wave, but think any
snow would not amount to much. The one concern this evening would be
possible strengthening northwest winds behind the front. Models
suggest speed around 15 MPH are possible behind the front and any
snow that was falling could blow around some. Again think this may
be a marginal impact and last for a short period of time. Lows
tonight should fall into the teens as cold air moves in behind the
front.
.LONG TERM...(Sunday through Friday)
Issued at 223 AM CST SAT NOV 15 2014
Lingering flurries quickly come to an end early Sunday morning as
dry air continues to increase aloft with the upper forcing
exiting. A piece of energy from the main upper trough progresses
through Kansas during the afternoon as subsident air quickly
follows and scours cloud deck to the south. A secondary and colder
than previous 1040 MB surface high begins to spread into the CWA
as highs struggle into the 20s. Temps from this point on become
colder through Tuesday as the arctic airmass spreads across much
of the country. Coldest night thus far in the season will be on
Tuesday morning as all guidance points at record cold lows in the
single digits. A rebound in temps commences through the end of the
period as the surface high shifts east and warmer air advects
northward, boosting highs near 40 degrees Wednesday through
Friday. A poignant blocking ridge across the western CONUS will
prevail dry northwest flow aloft through Thursday with indication
from the GFS/ECMWF on the ridge beginning to break down Friday as
an upper trough enters the west coast.
&&
.AVIATION...(For the 12Z TAFs through 12Z Sunday Morning)
Issued at 523 AM CST SAT NOV 15 2014
An area of snow continues to move northeast towards the terminals.
Based on radar, the snow may impact the airports 1-2 hours sooner
the the HRRR or RAP suggest. Have kept a tempo for IFR conditions
since the NAM and GFS show potential for upright instability and
brief periods of more intense snowfall. Otherwise think there is a
short window for accumulating snowfall. Main uncertainty with the
forecast are the CIGS. NAM MOS wants to keep a prolonged period of
MVFR conditions after the snow is expected to diminish. Based on
obs over southwest MO and northeast OK, this seems unlikely. Did
bring some MVFR CIGS back in after the FROPA. But this to should
not last long as dry air advects in from the northwest.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY until 6 PM CST this evening FOR
KSZ008>012-020>024-026-034>040-054>056-058-059.
&&
$$
SHORT TERM...Wolters
LONG TERM...Bowen
AVIATION...Wolters
AREA FORECAST DISCUSSION
NWS GOODLAND KS
405 AM MST SAT NOV 15 2014
.SHORT TERM...(TODAY THROUGH MONDAY NIGHT)
ISSUED AT 404 AM MST SAT NOV 15 2014
MAIN FORECAST CONCERN WILL BE WINTER WEATHER EVENT OCCURRING
THROUGH TONIGHT. SATELLITE CONTINUING TO SHOW AN AMPLIFIED PATTERN
FROM THE EASTERN PACIFIC INTO EASTERN NORTH AMERICA. CURRENTLY
NEARLY ZONAL FLOW OVER OUR AREA WITH MULTIPLE SMALL SCALE WAVES
EMBEDDED WITHIN THAT FLOW. STRONG...COLD AND RATHER COMPLEX UPPER
TROUGH IS MOVING THROUGH THE NORTH CENTRAL OF THE COUNTRY.
SATELLITE ALSO SHOWING DRY MID LEVEL AIR MASS IN PLACE AHEAD OF
INCOMING NORTHERN TROUGH. ANOTHER STRONG COLD FRONT IS APPROACHING
FROM THE NORTH.
AT JET LEVEL...MODELS LOOKED LIKE THEY INITIALIZED FINE. AT MID
LEVELS...THE GFS WAS DOING A LITTLE BETTER THAN THE ECMWF AND
CANADIAN. THE SREF WAS DOING THE BEST AT THE SURFACE. ALL THE
MODELS WERE OKAY ON THE LOW LEVEL THERMAL FIELD.
TODAY/TONIGHT...THE DAY STARTS OUT WITH AREA IN SUBSIDENCE FROM
DEPARTING JET. AFTER THIS MODELS DISAGREE WHERE THE MAIN JET
ENERGY WILL BE THROUGH THE REST OF THE PERIOD. BY 18Z IT LOOKS
LIKE A LEFT FRONT QUADRANT WILL BEGIN AFFECTING THE AREA. BY LATE
IN THE AFTERNOON INTO THE EVENING...THERE MAY BE A RIGHT REAR
QUADRANT ACROSS THE SOUTHEASTERN PORTION OF THE AREA. AFTER THAT
THE JET IS WELL SOUTH.
CURRENTLY INITIAL SHORTWAVE TROUGH IS MOVING THROUGH AND PRODUCING
LIGHT SNOW OVER SOUTHERN AND EASTERN SECTIONS. MODELS HAVE A GOOD
HANDLE ON THIS INITIAL SHORTWAVE TROUGH. CURRENT RADAR SHOWS THAT
THE MOST INTENSE SNOWFALL IS TO THE SOUTH OF AREA AND MOVING
THROUGH RATHER QUICKLY. ALL NIGHT THE HRRR HAS BEEN CATCHING THE
CURRENT RADAR TRENDS EXTREMELY WELL AND IT ALSO MATCHES UP WELL
WITH THE ABOVE MENTIONED MID AND UPPER LEVEL LIFT. OTHER OUTPUT IS
TOO FAR NORTH WITH THE PRECIPITATION SHIELD. SO WILL LEAN HEAVILY
ON THE HRRR FOR PRECIPITATION EARLY ON AND THEN TREND MORE TOWARD
THE CANADIAN/ECMWF AFTER THAT.
SO LITTLE TO NO SNOW FALL WILL END UP FALLING OVER THE WESTERN
HALF TO TWO THIRDS THIS MORNING WITH MOST OF THE SNOW OCCURRING IN
THE EASTERN SIX COUNTIES THROUGH MID MORNING. UPSTREAM SATELLITE
IS SHOWING A CLEARING TREND BEHIND THIS EXITING SHORTWAVE AND A
DRY AIR MASS IN ADVANCE OF THE NEXT SHORTWAVE TROUGH. AFTER THE
SNOW ENDS THIS MORNING...THE NEXT BATCH OF LIGHT SNOW WILL DEVELOP
TO OUR NORTH AND NORTHWEST BY LATE IN THE MORNING TO EARLY
AFTERNOON. THIS AREA THEN MOVES ACROSS THE AREA THROUGH THE REST
OF THE NIGHT WITH THE MOST SNOWFALL OCCURRING BEFORE MIDNIGHT. IT
IS POSSIBLE THAT SOME LOCATIONS MAY NOT SEE ANY SNOW UNTIL LATER
THIS AFTERNOON TO EARLY THIS EVENING.
MODELS...ESPECIALLY THE GFS...TEND TO BE TOO DEEP WITH THE
MOISTURE AND THEREFORE OVERPRODUCES PRECIPITATION. THE DRIER AIR
MASS UPSTREAM MAKES SENSE SINCE MOISTURE IN THE WESTERLY FLOW
ALOFT IS GETTING WRUNG BY THE HIGHER TERRAIN OVER COLORADO. SO PER
THE REASONING GIVEN ABOVE...SNOWFALL AMOUNTS WILL BE MUCH LIGHTER
THAN PREVIOUSLY EXPECTED WITH TOTAL AMOUNTS NOW ANTICIPATED TO BE
AROUND AN INCH OR LESS. IT IS ALSO POSSIBLE THAT WHEN THE COLD
FRONT MOVES THROUGH LATER TODAY...THAT LITTLE IF ANY SNOW WILL BE
ON THE GROUND. ALSO CONSIDERING WHAT LITTLE SNOW HAS ALREADY
FALLEN AND THAT THERE WILL BE A SIGNIFICANT LULL BEFORE THE NEXT
SNOWFALL STARTS...HAVE DECIDED TO CANCEL THE WINTER WEATHER
ADVISORY. IF SNOWFALL ENDS UP BEING WORSE THAN CURRENTLY
EXPECTED...THEN A MORE SHORT TERM ADVISORY CAN BE ISSUED TO HANDLE
THAT SINCE NOTHING IS GOING ON AT THIS TIME.
NOW FOR TEMPERATURS. JUST LIKE LAST NIGHT...MODELS ARE TOO COOL
WITH THE CURRENT TEMPERATURES DUE TO CLOUD COVER AND CONTINUED
WARM AIR ADVECTION. FRONT IS ALSO EXPECTED TO ARRIVE LATER AND
WILL NOT MOVE THROUGH THE EASTERN PORTION OF THE AREA UNTIL THIS
AFTERNOON. THERE ALSO MAY BE ENOUGH BREAKS IN THE CLOUD COVER TO
ALLOW SOME SUNSHINE TO OCCUR. A LOT OF THE OUTPUT IS SAYING
WARMER AND TRENDED IN THAT DIRECTION.
SUNDAY/SUNDAY NIGHT...DRY CONDITIONS EXPECTED THROUGH THE PERIOD.
SHOULD SEE A DECENT AMOUNT OF SUN WITH WINDS BEING MOSTLY FROM A
DOWNSLOPE DIRECTION. MODELS ARE SHOW TEMPERATURES WARMER THAN
YESTERDAY. MODELS HAVE HAD A RECENT COOL BIAS AS WELL. SO WENT
NEAR THE WARMER GUIDANCE.
MONDAY/MONDAY NIGHT...STRONG UPPER SYSTEM DIGS INTO THE NORTH
CENTRAL PORTION OF THE COUNTRY JUST BEFORE AND DURING THIS PERIOD.
THIS PUSHES ANOTHER COLD FRONT THROUGH THE AREA AND SHOULD MAKE
FOR COOLER TEMPERATURES COMPARED TO SUNDAY MAXES. HOWEVER...THERE
IS A BIG DIFFERENCE IN THE AMOUNT OF COOLING INDICATED BY THE
MODELS. DID NOT GO WITH THE COLDEST GUIDANCE BUT TRENDED IN THE
COLDER DIRECTION.
.LONG TERM...(TUESDAY THROUGH FRIDAY)
ISSUED AT 404 AM MST SAT NOV 15 2014
COMPARING TONIGHTS MODELS RUN TO LAST NIGHTS THE LONG WAVE RIDGE
OVER THE WEST COAST OF THE UNITED STATES WILL STILL MOVE EAST AND BE
LOCATED OVER THE ROCKIES BY FRIDAY. HOWEVER... UNLIKE LAST NIGHTS
RUN... WHERE THE RIDGE LOOKED LIKE IT WOULD FLATTEN... IT NOW
SEEMS IT WILL MAINTAIN ITS AMPLITUDE. THIS WILL PRODUCE A
PERDOMINATELY NORTHWESTERN UPPER LEVEL FLOW OVER THE TRI-STATE
AREA DURING THE EXTENDED.
YESTERDAYS QUESTION WAS WHEN WILL THE NEXT FRONT PASS OVER THE AREA.
TONIGHTS RUN OF THE GFS... NAVGEM AND ECMWF ARE IN BETTER AGREEMENT
ON THIS FRONT COMPARED TO LAST NIGHTS RUN. THEY ALL HAVE THE FRONT
PASSING OVER THE AREA ON THE 19TH BWTWEEN 00Z AND 06Z. THEY ALSO
SHOW THIS SYSTEM TO BE A DRY ONE AND WILL HAVE LITTLE TO NO EFFECT
ON THE TEMPERATURES. IT DOES SHOW A SHIFT IN THE WINDS FOLLOWED BY
LIGHT WINDS AS HIGH PRESSURE BUILDS IN BEHIND IT FOR THE REST OF THE
EXTENDED.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1025 PM MST FRI NOV 14 2014
MONITOR FOR POTENTIAL WINTER PRECIP AT BOTH KGLD AND KMCK
TERMINALS DURING THE TAF PERIOD. HIGHEST CONFIDENCE IN LOWER
VIS/CIGS IS 09Z-15Z PERIOD...WHEN MVFR...POSSIBLY IFR WILL OCCUR
AS LIGHT SNOW DEVELOPS. COULD SEE A BRIEF PERIOD OF FREEZING
DRIZZLE AROUND 12-15Z...HOWEVER CONFIDENCE IS TOO LOW IN
COVERAGE/TIMING TO ADD MENTION. THERE SHOULD BE IMPROVEMENT IN
CONDITIONS BY MIDDAY...WITH ANOTHER ROUND OF SNOW BY LATE SATURDAY
AFTERNOON. THERE COULD BE BRIEF REDUCTIONS IN VIS/CIGS WITH THIS
SECOND BATCH OF SNOW...HOWEVER THERE ARE STILL TIMING AND COVERAGE
VARIATIONS BETWEEN MODELS WITH THIS SECOND ROUND OF SNOW...SO I
KEPT VFR CONDITIONS IN THE AFTERNOON/EVENING SATURDAY.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...BULLER
LONG TERM...BDW/BULLER
AVIATION...DR
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
635 AM EST SAT NOV 15 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 416 AM EST SAT NOV 15 2014
A QUIET START TO THE SHORT TERM FORECAST THIS MORNING...AS THE AREA
IS ON THE NORTHEAST EDGE OF A HIGH CENTERED FROM THE MID/UPPER
MISSISSIPPI VALLEY TO THE OHIO RIVER VALLEY. THIS HAS LED TO A
CLEAR AND COLD NIGHT ACROSS AT LEAST HALF OF THE CWA. WHERE WINDS
HAVE DECOUPLED (GENERALLY ACROSS THE INTERIOR WEST AND NEAR THE
WISCONSIN BORDER)...TEMPERATURES HAVE FALLEN INTO THE SINGLE
DIGITS BELOW ZERO. MEANWHILE...OVER THE CENTRAL AND EAST WHERE THE
WINDS HAVE BEEN STAYING UP...TEMPERATURES HAVE BEEN IN THE UPPER
SINGLE DIGITS ABOVE ZERO TO MID TEENS.
OVER LAKE SUPERIOR AND THE KEWEENAW...COLD AIR CONTINUING TO FLOW
OVER THE RELATIVELY WARM WATERS OF LAKE SUPERIOR WAS PRODUCING
MAINLY LAKE EFFECT CLOUDS THIS PAST EVENING AND INTO THE EARLY
OVERNIGHT HOURS. BUT STARTED SEEING WEAK LAKE EFFECT BANDS
OVER EASTERN LAKE SUPERIOR ON THE CANADIAN RADAR AT MONTREAL RIVER
SHORTLY AFTER MIDNIGHT. INVERSION IS RIGHT AT 875-850MB ON 00Z
KGRB/KINL SOUNDINGS AND THE LIMITED MOISTURE ON THE NORTH EDGE OF
THE HIGH HAVE BEEN THE MAIN LIMITING FACTORS TO LAKE EFFECT SNOW
EARLY THIS MORNING. KMQT VWP HAS BEEN SHOWING THE WINDS A LITTLE
MORE OUT OF THE WEST-NORTHWEST AND CONTRIBUTING TO THE LAKE EFFECT
CLOUDS NOSING SOUTHEAST INTO BARAGA...SOUTHERN HOUGHTON...AND EVEN
FAR NORTHERN IRON COUNTY EARLY THIS MORNING. BUT AS WE HEAD INTO
THE MORNING HOURS...MODELS SHOWING THE WINDS GOING BACK TO A MORE
WESTERLY AND POTENTIALLY WEST-SOUTHWESTERLY DIRECTION AND CONFINING
THE LAKE EFFECT CLOUDS AND SNOW POTENTIAL TO THE KEWEENAW AND OFF
THE SHORELINE FROM GRAND MARAIS EASTWARD. THIS WILL ALSO BE AIDED
BY THE LAND BREEZE THAT HAS DEVELOPED ALONG THE EASTERN U.P.
SHORELINE AND WILL AID IN KEEPING THE BANDS OFFSHORE THERE. THE
COVERAGE OF THE SHOWERS IS A LITTLE BIT OF A CONCERN DUE TO THE
LIMITED MOISTURE...BUT WOULD EXPECT SOME UPTICK IN THE SNOW SHOWERS
AS 875MB TEMPERATURES FALL FROM -11C ON THE RAP ANALYSIS TO -13/-14C
BY THIS AFTERNOON. THUS...WILL CONTINUE TO SHOW POPS RAMPING UP TO
HIGH CHANCES OVER THE KEWEENAW. WITH MUCH OF THE LAKE EFFECT CLOUD
BELOW THE DGZ...WILL KEEP SNOW RATIOS ON THE LOW END FOR LAKE EFFECT
AND ONLY HAVE ACCUMULATIONS AT A DUSTING TO AN INCH IN THAT AREA.
OVER THE REST OF THE AREA...EXPECT A SUNNY START TO THE DAY WHICH
WILL ALLOW TEMPERATURES TO RISE TO THE LOW-MID 20S THIS AFTERNOON.
EXPECT MORE OF A FILTERED SUNSHINE IN THE AFTERNOON AS HIGH CLOUDS
MOVE IN AHEAD OF THE WAVE BRUSHING THE AREA LATE TONIGHT.
HEADING INTO TONIGHT...FOCUS TURNS TO THE SHORTWAVE CURRENTLY
MOVING THROUGH WYOMING. THIS WAVE WILL QUICKLY SHIFT EAST THROUGH
NEBRASKA AND SOUTH DAKOTA TODAY AND THEN LIFT NORTHEAST ACROSS
NORTHERN LAKE MICHIGAN LATE TONIGHT AND SUNDAY MORNING. EXPECT THE
HIGH CLOUDS TO THICKEN THIS EVENING AND MID CLOUDS TO MOVE IN
DURING THE LATE EVENING AND OVERNIGHT. ANOTHER SHORTWAVE (CURRENTLY
IN COLORADO) WILL LIFT NORTHEAST OUT AHEAD OF THE MAIN WAVE AND
COULD PRODUCE A FEW SHOWERS AROUND MIDNIGHT. THE BETTER/MAIN
FORCING (GENERALLY ABOVE 700MB) COMES FROM THE SECOND SHORTWAVE AND
LOOKS TO STAY SOUTHEAST OF THE AREA...BUT DO EXPECT MENOMINEE COUNTY
AND AREAS ALONG THE LAKE MICHIGAN SHORELINE TO SEE THE BEST
OPPORTUNITY FOR ACCUMULATING SNOW. CURRENT FORECAST HAS SNOWFALL
AMOUNTS UP TO AN INCH OVER SOUTHERN MENOMINEE COUNTY AND TAPERING
OFF TO A HALF INCH OR LESS SOUTH OF A LINE FROM IRON MOUNTAIN TO
MANISTIQUE. SINCE THE NORTHERN EDGE OF THE FORCING WILL BE JUST
BRUSHING THE AREA...DO EXPECT A SHARP CUTOFF TO THE PRECIPITATION TO
THE NORTHWEST AND KEEP THE SNOW CHANCES TO THE SOUTHEAST OF A LINE
FROM MARQUETTE TO WATERSMEET. AS FOR THE LAKE EFFECT OVER THE
KEWEENAW...THIS WAVE WILL BACK THE LOW LEVEL WINDS FARTHER TO THE
SOUTHWEST AND FOCUS ANY LINGERING LAKE EFFECT TO THE FAR NORTHERN
PORTIONS OF THE KEWEENAW PENINSULA. ACCUMULATIONS WILL REMAIN LIGHT
AND BELOW 2 INCHES.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 409 AM EST SAT NOV 15 2014
A HI AMPLITUDE PATTERN FEATURING A TROF OVER CENTRAL AND ERN
NAMERICA DOWNSTREAM OF A RDG ALONG THE W COAST WL DOMINATE THE WX
PATTERN THIS COMING WEEK...LEADING TO PERSISTENT BLO TO WELL BLO
NORMAL TEMPS THRU THE WEEK. THE MOST SGNFT WX CONCERN WL BE THE
IMPACT OF A POTENT SHRTWV THAT IS FCST TO DIG SEWD THRU THE UPR LKS
EARLY IN THE WEEK AND AMPLIFY THE TROF. THIS DISTURBANCE WL ALMOST
CERTAINLY BRING ANOTHER ROUND OF MODERATE TO HEAVY LES AND SOME BLSN
MAINLY TO THE NW WIND SN BELTS NEAR LK SUP ON MON INTO TUE. YET
ANOTHER DISTURBANCE DIGGING THRU THE UPR TROF MAY BRING MORE SGNFT
LES ON WED INTO THU.
SUN...ONGOING LIGHT SN OVER THE SE CWA WL END BY EARLY IN THE AFTN
AS SHRTWV OVER ERN WI AT 12Z AND ACCOMPANYING DYNAMIC FORCING/
DEEPER MSTR EXIT TO THE E THRU LOWER MI AND INTO FAR SE ONTARIO IN
THE AFTN. AXIS OF DRIER AIR/DEEP LYR QVECTOR DVGC BTWN THIS
DEPARTING SHRTWV AND ANOTHER MORE POTENT SHRTWV DIGGING SE THRU
SCENTRAL CANADA WL THEN BRING A PERIOD OF DRY WX TO THE CWA.
ALTHOUGH H85 TEMPS ARE FCST TO BE AS LO AS -12 TO -13C...THE FCST
230 DEGREE LLVL FLOW IN ADVANCE OF THE APRCHG SHRTWV WL HOLD ANY LES
MAINLY TO THE NW OF THE KEWEENAW PENINSULA AND E OF LUCE/SCHOOLCRAFT
COUNTIES. ALTHOUGH DPVA/DEEP LYR QVECTOR CNVGC IN ADVANCE OF THE
INCOMING SHRTWV ARE FCST TO INVADE THE WRN CWA LATER IN THE DAY...
THE ABSENCE OF ANY SGNFT LLVL MSTR INFLOW WL MAINTAIN DRY WX THRU
00Z MON UNDER INCRSG HI/MID CLDS.
SUN NIGHT...INCOMING SHRTWV/SFC LO ARE FCST TO DRIFT OVER NRN LK SUP
BY 12Z MON AND CAUSE 12HR H5 HGT FALLS UP TO 120M ACROSS THE UPR
LKS. AXIS OF DPVA/DEEP LYR QVECTOR CNVGC WITHIN THE COMMA TAIL OF
THIS FEATURE ARE FCST TO SWING ACROSS UPR MI. HOWEVER...POTENTIAL
FOR WIDESPREAD SN IN ADVANCE OF THE SHRTWV WL BE LIMITED BY THE
ABSENCE OF LLVL MOISTENING/PWAT UNDER 0.25 INCH/H7 SPECIFIC HUMIDITY
NO MORE THAN ABOUT 1 G/KG. STILL LOOKS LIKE THE LLVL FLOW WL NOT
BACK SUFFICIENTLY TO ALLOW ANY LK ENHANCED OFF LK MI TO IMPACT LUCE
OR SCHOOLCRAFT COUNTIES. THE BEST CHC FOR MORE WIDESPREAD/HEAVIER
SNOW WL BE OVER THE W MAINLY LATE FOLLOWING COLD FROPA AND WIND
SHIFT TO AN UPSLOPE NW DIRECTION. ARRIVAL OF H85 TEMPS AROUND -15C
WITH SHARP CYC FLOW/LINGERING DEEP MSTR UNDER THE FALLING HGTS WILL
WARRANT KEEPING LIKELY TO CATEGORICAL POPS OVER THE W. WL GO NO HIER
THAN CHC POPS ELSEWHERE...WITH THE LOWEST SCHC POPS OVER THE
SCENTRAL.
MON/MON NGT...AS THE UPR TROF DEEPENS INTO THE GREAT LKS AND A
CLOSED H5 LO FORMS...UPR MI IS FCST TO BE UNDER SHARP...CYC W
VEERING NW FLOW ON MON AND NNW-NW FLOW ON MON NGT. FCST SDNGS SHOW
DEEP MOISTURE/INSTABILITY AS H5 TEMPS DIP TOWARD -40C. GIVEN H85
TEMPS FALLING TO -16C TO -18C AND THE DEEP INSTABILITY/MOISTURE WITH
THE CYC LLVL FLOW...CATEGORICAL POPS ARE WARRANTED IN THE FAVORED SN
BELTS. GUSTY WINDS UNDER THE SHARP PRES GRADIENT/DESTABILIZATION WL
CAUSE BLSN IN ADDITIONAL TO THE HEAVIER LES. FAVORABLE OMEGA PROFILE
WITHIN THE DGZ SITUATED BTWN ABOUT 1-5K FT AGL WL ALSO ENHANCE
SN/WATER RATIOS DESPITE THE IMPACT OF THE STRONG WINDS TO FRAGMENT
THE SN FLAKES. RIGHT NOW... THE FAR W IN ONTONAGON/GOGEBIC COUNTIES
LOOKS TO PICK UP THE HEAVIEST SN ON MON NGT...WITH ADDITIONAL HEAVY
LES IMPACTING AREAS E OF MARQUETTE LATER ON MON THRU MON NGT. LATER
SHIFTS NO DOUBT WL NEED TO HOIST LES HEADLINES. THE STRONG NW WINDS
MAY ALSO CAUSE HI ENOUGH WAVES ON LK SUPERIOR TO BRING SOME MINOR
BEACH EROSION/FLOODING IN AREAS MOST EXPOSED TO THE HIER WINDS/WAVES
BEGINNING ON LATE MON. FOR NOW...WL CONTINUE TO MENTION THE SGFNT
LES POTENTIAL/BLSN AND HI WAVES IN THE HWO PRODUCT AND EHWO GRAPHICS.
TUE/TUE NGT...AS THE CLOSED LO SHIFTS INTO QUEBEC AND 12HR H5 HGT
RISES APRCH 100M ON TUE IN THE LARGER SCALE DNVA AHEAD OF TRAILING
H5 RDG AXIS...MID LVL SUBSIDENCE/DRYING/TREND TOWARD NEUTRAL OR MORE
ACYC LLVL FLOW WL TEND TO WEAKEN THE LES W TO E. STEADILY BACKING
WINDS OVER THE W THRU THE DAY AND MAINLY DURING TUE AFTN OVER THE E
WL TEND TO LIMIT THE RESIDENCE TIME OF THE HEAVIER SN BANDS AND
SHIFT THE LES TO PRIMARILY OVER THE KEWEENAW AND TO THE E OF
MUNISING BY LATE IN THE DAY. DESPITE THIS DIMINISHING TREND...SN
TOTALS ON MON THRU TUE WL LIKELY APRCH OR EXCEED A FOOT IN THE
FAVORED SN BELTS OVER THE W CENTERED IN ONTONAGON COUNTY AND E OF
MUNISING. AS THE FLOW CONTINUES TO BACK TOWARD THE SW ON TUE NGT IN
ADVANCE OF NEXT CLIPPER SHRTWV DIGGING SEWD TOWARD MN...THE MAIN
AREA OF LES SHOULD SHIFT INTO LK SUP. BUT MORE WIDESPREAD SN MAY
ARRIVE LATE AT NGT AT LEAST OVER THE W WITH THE ONSET OF MORE
VIGOROUS DYNAMIC FORCING/HGT FALLS IN THE DPVA AHEAD OF THE NEXT
SHRTWV.
WED THRU FRI...PASSAGE OF POTENT SHRTWV/VIGOROUS DYNAMIC FORCING WL
BRING THE THREAT OF A MORE WIDESPREAD SN AGAIN ON WED DESPITE RATHER
LIMITED ABSOLUTE MSTR /FCST PWAT UNDER 0.25 INCH/. MORE LES WL BE
THE RULE ON THU INTO FRI MAINLY IN THE NW WIND SN BELTS AS ANOTHER
COLD SHOT WITH H85 TEMPS AS LO AS -16 TO -18C POURS INTO THE UPR LKS
BEHIND THE DEPARTING SHRTWV. LONGER RANGE MODELS CONTINUE TO POINT
TOWARD SOME MODERATION IN THE COLD NEXT WEEKEND.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 635 AM EST SAT NOV 15 2014
WESTERLY WINDS OFF LAKE SUPERIOR WILL CONTINUE TO LEAD TO LAKE
EFFECT CLOUDS (HIGH END MVFR) AND SOME SNOW SHOWERS AT KCMX THROUGH
MUCH OF THE PERIOD. CONFIDENCE IS LOW ON THE ORGANIZED NATURE OF
THE LAKE EFFECT SNOW...DUE TO THE EXISTING DRY AIR...SO WILL KEEP
VISIBILITIES AT VFR VALUES.
FOR KIWD/KSAW...EXPECT VFR CONDITIONS DUE TO UNFAVORABLE WIND
DIRECTIONS FOR LAKE EFFECT. LEFT OVER LAKE EFFECT CLOUDS FROM THE
KEWEENAW HAVE BEEN TRYING TO PUSH INTO NORTHERN MARQUETTE COUNTY
THIS MORNING. WITH WINDS OUT OF THE WEST-NORTHWEST...THEY WILL TRY
TO APPROACH KSAW BUT FEEL THEY WILL STAY MAINLY TO THE NORTH OF THE
SITE. AN APPROACHING UPPER LEVEL DISTURBANCE WILL LEAD TO
INCREASING HIGH/MID CLOUDS THIS AFTERNOON AND TONIGHT. KSAW WILL BE
THE CLOSEST FOR SOME SNOW SHOWERS AND WILL MENTION VCSH LATE TONIGHT
AS THEY APPROACH.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 409 AM EST SAT NOV 15 2014
UNDER A SHARP PRES GRADIENT BETWEEN HI PRES IN THE OH RIVER VALLEY
AND LO PRES OVER HUDSON BAY...PLAN ON W WINDS UP TO 20-30KTS INTO
SUN. THE WINDS WL THEN BACK TOWARD THE SW AND DIMINISH TO UP TO
25KTS IN ADVANCE OF ANOTHER STRONG DISTURBANCE MOVING THRU SCENTRAL
CANADA AND INTO NORTHERN LAKE SUPERIOR ON MON MORNING. FOLLOWING THE
PASSAGE OF THIS LO TO THE E...THE PRES GRADIENT WILL TIGHTEN AND THE
INSTABILITY WILL INCREASE AS ANOTHER SURGE OF COLD AIR FLOWS OVER
THE RELATIVELY WARM LAKE WATERS. THE RESULT WILL BE A PERIOD OF NW
GALES ON MON INTO TUE. SINCE THIS AIRMASS WILL BE SUFFICIENTLY
COLD...THERE WILL LIKELY BE SOME FREEZING SPRAY IN SOME AREAS. THE
BEST CHANCE FOR THE GALES WILL BE OVER CENTRAL LAKE SUPERIOR. AS THE
LO PRES MOVES AWAY ON TUE AND HI PRES SHIFTS E...EXPECT THE WINDS TO
BACK TO THE W AND DIMINISH TO 25 TO 30KTS. THE PASSAGE OF ANOTHER
STRONG DISTURBANCE ON WED MAY LEAD TO ANOTHER NW GALE EVENT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...KC
AVIATION...SRF
MARINE...KC
AREA FORECAST DISCUSSION
NWS BISMARCK ND
839 AM CST SAT NOV 15 2014
.UPDATE...
ISSUED AT 839 AM CST SAT NOV 15 2014
UPDATED THE FORECAST TO CANCEL THE WIND CHILL ADVISORY FOR WEST
CENTRAL AND NORTHWESTERN NORTH DAKOTA THIS MORNING.
11-3.9 MICRON SATELLITE IMAGERY SHOWS A STRATUS DECK BEGINNING TO
DRIFT SOUTH ACROSS NORTHWESTERN NORTH DAKOTA. ISOLATED FLURRIES
HAVE BEEN REPORTED UNDER THIS STATUS DECK. AS A RESULT...ADDED
ISOLATED FLURRIES TO THE FORECAST NORTHWEST THIS MORNING. THE
STRATUS SHOULD BEGIN TO BREAK UP SOMEWHAT BY THIS AFTERNOON. THE
REMAINING WEATHER ELEMENTS ARE IN GOOD SHAPE. THE UPDATED PRODUCTS
HAVE BEEN SENT.
UPDATE ISSUED AT 653 AM CST SAT NOV 15 2014
NO SIGNIFICANT CHANGES WITH THIS FORECAST UPDATE OTHER THAN TO
BLEND TO OBSERVED TRENDS THROUGH 12 UTC. WILL LEAVE THE WIND CHILL
ADVISORY IN PLACE AS BORDERLINE ADVISORY CRITERIA VALUES NEAR -25
WILL CONTINUE EARLY THIS MORNING.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 406 AM CST SAT NOV 15 2014
MAIN HIGHLIGHT THIS MORNING IS A WIND CHILL ADVISORY FOR PORTIONS OF
THE FAR WEST. COLDER AIR COMING IN FROM THE WEST AND BRISK WINDS
WILL DOMINATE THROUGH MID MORNING. A POTENT SHORTWAVE AND ASSOCIATED
COLD FRONT SHIFTING SOUTH FROM CENTRAL CANADA WILL BEGIN TO IMPACT
WESTERN/NORTHERN NORTH DAKOTA LATE SATURDAY NIGHT THEN SPREAD SOUTH
SUNDAY MORNING.
THE LATEST WATER VAPOR IMAGERY SHOWS AN ELONGATED UPPER TROUGH
FROM HUDSON BAY SOUTHWEST INTO MONTANA. AHEAD OF THE TROUGH...A
SHORTWAVE WAS SEEN ALONG THE WYOMING/MONTANA BORDER MOVING EAST TO
SOUTHEAST WITH TIME...AS THE SURFACE LOW REMAINS FARTHER SOUTH.
LIGHT SNOW ASSOCIATED WITH THIS SYSTEM EXTENDED ACROSS CENTRAL AND
SOUTHERN SOUTH DAKOTA AND IS MOVING EAST. FARTHER UPSTREAM...AN
AREA OF STRATUS OVER SOUTHERN SASKATCHEWAN PER LATEST FOG/STRATUS
LOOP CONTINUES A SOUTHEAST MOVEMENT. THE HRRR AND RAP13 SHIFT THIS
INTO NORTHWEST AND NORTH CENTRAL NORTH DAKOTA BETWEEN 12Z-21Z
TODAY. CONCUR WITH THIS AND ADJUSTED SKY GRIDS ACCORDINGLY.
ELSEWHERE ISOLATED FLURRIES WITH POCKETS OF STRATUS CONTINUE EARLY
THIS MORNING IN THE FAR SOUTHWEST...ALONG AND SOUTH OF LAKE
SAKAKAWEA...AND IN THE SOUTHERN JAMES RIVER VALLEY. ANOTHER VERY
COLD DAY AHEAD WITH HIGHS IN THE SINGLE DIGITS ABOVE ZERO IN THE
WEST AND SOUTHWEST...TO LOWER/MIDDLE TEENS ELSEWHERE. BRISK
NORTHWEST WINDS THIS AFTERNOON 10 TO 25 MPH.
FOR TONIGHT...ATTENTION TURNS TO A STRONG SHORTWAVE TROUGH AND
ASSOCIATED SHARP COLD FRONT HEADING DUE SOUTH FROM THE NORTHWEST
TERRITORIES. THE COLD FRONT WILL PASS THROUGH NORTHWEST AND NORTH
CENTRAL AFTER MIDNIGHT WITH INCREASING WINDS TOWARD AND SHORTLY
AFTER DAYBREAK ON SUNDAY.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 406 AM CST SAT NOV 15 2014
BLOWING SNOW POTENTIAL ON SUNDAY HIGHLIGHTS THE EXTENDED FORECAST.
THE 00 UTC GUIDANCE SUITE CONTINUES THE TREND OVER THE PAST
SEVERAL DAYS OF A REINFORCING COLD FRONT TO PROPAGATE ACROSS
WESTERN AND CENTRAL NORTH DAKOTA SUNDAY MORNING IN ASSOCIATION
WITH ITS PARENT CLIPPER SYSTEM ACROSS EASTERN MANITOBA INTO
WESTERN ONTARIO. STRONG NORTHWEST WINDS INTERACTING WITH THE
SNOWFALL FROM LAST WEEKEND PRESENTS A BLOWING SNOW THREAT. THE
CHALLENGE IS IF BLIZZARD CRITERIA WILL BE MET ACROSS THE SOUTHWEST
WHERE THE MOST SNOW WAS RECEIVED. THE SNOW HAS BEEN ON THE GROUND
FOR A WEEK...HOWEVER...IT IS UNCRUSTED AND HAS NOT BEEN
SIGNIFICANTLY COMPACTED. THAT SAID....BEING THE FIRST SNOWFALL OF
THE SEASON...SOME OF THE SNOW MAY BE ADVERSE TO BEING LOFTED FROM
BEING TRAPPED IN THE GRASSES. THUS...WILL FORGO A BLIZZARD WATCH
FOR NOW...AND HIGHLIGHT THE THREAT WITH NEAR-BLIZZARD CONDITIONS
POSSIBLE IN THE REMAINDER OF THE PRODUCT SUITE AND SPECIAL WEATHER
STATEMENT. PROBABILITIES FOR HALF-MILE VISIBILITIES USING THE
BAGGALY BLOWING SNOW MODEL TAKING INTO ACCOUNT SNOW AGE AND THE
LACK OF SIGNIFICANT FALLING SNOW PRODUCE RESULTS THAT DO NOT FAVOR
BLIZZARD CRITERIA BEING MET. FURTHERMORE...THE STRENGTH OF
ISALLOBARIC FORCING AND WINDS AT THE TOP OF THE MIXED LAYER
DECREASE THROUGH THE DAY...BEING GREATEST PRIOR TO THE PRE-FRONTAL
INVERSION BEING BROKEN. CERTAINLY AT LEAST A WINTER WEATHER
ADVISORY FOR BLOWING SNOW WILL BE NEEDED FOR THE SOUTHWEST...AND
POSSIBLY INTO THE SOUTH CENTRAL. GIVEN FURTHER EVALUATION
TODAY.... WOULD NOT BE SURPRISED IF A BLIZZARD WATCH IS ISSUED.
THEREAFTER...THE DE-AMPLIFICATION OF THE ANOMALOUS UPPER LEVEL
PATTERN IS SLOWER WITH THE 15/00 UTC GUIDANCE CONSENSUS COMPARED
TO PREVIOUS RUNS...WITH A RECOVERY FROM ARCTIC AIR LIKELY DELAYED
UNTIL LATE NEXT WEEK AT THE EARLIEST.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 653 AM CST SAT NOV 15 2014
SATELLITE AND SURFACE OBSERVATIONS CONTINUE TO SHOW MVFR CIGS
ENTERING WESTERN AND PORTIONS OF SOUTH CENTRAL NORTH DAKOTA THIS
MORNING. THIS IS FORECAST TO PERSIST INTO THE EARLY AFTERNOON.
CIGS AT KDIK WILL FREQUENTLY VARY BETWEEN MVFR/IFR...WHILE MVFR
CIGS WILL CONTINUE TO FILL IN AT KBIS BY 13Z...AND INTO KMOT BY
16Z. KJMS WILL REMAIN VFR TODAY WITH MVFR CIGS SOUTH OF THE
TERMINAL.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...TM
SHORT TERM...KS
LONG TERM...AYD
AVIATION...KS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
654 AM CST SAT NOV 15 2014
.UPDATE...
ISSUED AT 653 AM CST SAT NOV 15 2014
NO SIGNIFICANT CHANGES WITH THIS FORECAST UPDATE OTHER THAN TO
BLEND TO OBSERVED TRENDS THROUGH 12 UTC. WILL LEAVE THE WIND CHILL
ADVISORY IN PLACE AS BORDERLINE ADVISORY CRITERIA VALUES NEAR -25
WILL CONTINUE EARLY THIS MORNING.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 406 AM CST SAT NOV 15 2014
MAIN HIGHLIGHT THIS MORNING IS A WIND CHILL ADVISORY FOR PORTIONS OF
THE FAR WEST. COLDER AIR COMING IN FROM THE WEST AND BRISK WINDS
WILL DOMINATE THROUGH MID MORNING. A POTENT SHORTWAVE AND ASSOCIATED
COLD FRONT SHIFTING SOUTH FROM CENTRAL CANADA WILL BEGIN TO IMPACT
WESTERN/NORTHERN NORTH DAKOTA LATE SATURDAY NIGHT THEN SPREAD SOUTH
SUNDAY MORNING.
THE LATEST WATER VAPOR IMAGERY SHOWS AN ELONGATED UPPER TROUGH
FROM HUDSON BAY SOUTHWEST INTO MONTANA. AHEAD OF THE TROUGH...A
SHORTWAVE WAS SEEN ALONG THE WYOMING/MONTANA BORDER MOVING EAST TO
SOUTHEAST WITH TIME...AS THE SURFACE LOW REMAINS FARTHER SOUTH.
LIGHT SNOW ASSOCIATED WITH THIS SYSTEM EXTENDED ACROSS CENTRAL AND
SOUTHERN SOUTH DAKOTA AND IS MOVING EAST. FARTHER UPSTREAM...AN
AREA OF STRATUS OVER SOUTHERN SASKATCHEWAN PER LATEST FOG/STRATUS
LOOP CONTINUES A SOUTHEAST MOVEMENT. THE HRRR AND RAP13 SHIFT THIS
INTO NORTHWEST AND NORTH CENTRAL NORTH DAKOTA BETWEEN 12Z-21Z
TODAY. CONCUR WITH THIS AND ADJUSTED SKY GRIDS ACCORDINGLY.
ELSEWHERE ISOLATED FLURRIES WITH POCKETS OF STRATUS CONTINUE EARLY
THIS MORNING IN THE FAR SOUTHWEST...ALONG AND SOUTH OF LAKE
SAKAKAWEA...AND IN THE SOUTHERN JAMES RIVER VALLEY. ANOTHER VERY
COLD DAY AHEAD WITH HIGHS IN THE SINGLE DIGITS ABOVE ZERO IN THE
WEST AND SOUTHWEST...TO LOWER/MIDDLE TEENS ELSEWHERE. BRISK
NORTHWEST WINDS THIS AFTERNOON 10 TO 25 MPH.
FOR TONIGHT...ATTENTION TURNS TO A STRONG SHORTWAVE TROUGH AND
ASSOCIATED SHARP COLD FRONT HEADING DUE SOUTH FROM THE NORTHWEST
TERRITORIES. THE COLD FRONT WILL PASS THROUGH NORTHWEST AND NORTH
CENTRAL AFTER MIDNIGHT WITH INCREASING WINDS TOWARD AND SHORTLY
AFTER DAYBREAK ON SUNDAY.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 406 AM CST SAT NOV 15 2014
BLOWING SNOW POTENTIAL ON SUNDAY HIGHLIGHTS THE EXTENDED FORECAST.
THE 00 UTC GUIDANCE SUITE CONTINUES THE TREND OVER THE PAST
SEVERAL DAYS OF A REINFORCING COLD FRONT TO PROPAGATE ACROSS
WESTERN AND CENTRAL NORTH DAKOTA SUNDAY MORNING IN ASSOCIATION
WITH ITS PARENT CLIPPER SYSTEM ACROSS EASTERN MANITOBA INTO
WESTERN ONTARIO. STRONG NORTHWEST WINDS INTERACTING WITH THE
SNOWFALL FROM LAST WEEKEND PRESENTS A BLOWING SNOW THREAT. THE
CHALLENGE IS IF BLIZZARD CRITERIA WILL BE MET ACROSS THE SOUTHWEST
WHERE THE MOST SNOW WAS RECEIVED. THE SNOW HAS BEEN ON THE GROUND
FOR A WEEK...HOWEVER...IT IS UNCRUSTED AND HAS NOT BEEN
SIGNIFICANTLY COMPACTED. THAT SAID....BEING THE FIRST SNOWFALL OF
THE SEASON...SOME OF THE SNOW MAY BE ADVERSE TO BEING LOFTED FROM
BEING TRAPPED IN THE GRASSES. THUS...WILL FORGO A BLIZZARD WATCH
FOR NOW...AND HIGHLIGHT THE THREAT WITH NEAR-BLIZZARD CONDITIONS
POSSIBLE IN THE REMAINDER OF THE PRODUCT SUITE AND SPECIAL WEATHER
STATEMENT. PROBABILITIES FOR HALF-MILE VISIBILITIES USING THE
BAGGALY BLOWING SNOW MODEL TAKING INTO ACCOUNT SNOW AGE AND THE
LACK OF SIGNIFICANT FALLING SNOW PRODUCE RESULTS THAT DO NOT FAVOR
BLIZZARD CRITERIA BEING MET. FURTHERMORE...THE STRENGTH OF
ISALLOBARIC FORCING AND WINDS AT THE TOP OF THE MIXED LAYER
DECREASE THROUGH THE DAY...BEING GREATEST PRIOR TO THE PRE-FRONTAL
INVERSION BEING BROKEN. CERTAINLY AT LEAST A WINTER WEATHER
ADVISORY FOR BLOWING SNOW WILL BE NEEDED FOR THE SOUTHWEST...AND
POSSIBLY INTO THE SOUTH CENTRAL. GIVEN FURTHER EVALUATION
TODAY.... WOULD NOT BE SURPRISED IF A BLIZZARD WATCH IS ISSUED.
THEREAFTER...THE DE-AMPLIFICATION OF THE ANOMALOUS UPPER LEVEL
PATTERN IS SLOWER WITH THE 15/00 UTC GUIDANCE CONSENSUS COMPARED
TO PREVIOUS RUNS...WITH A RECOVERY FROM ARCTIC AIR LIKELY DELAYED
UNTIL LATE NEXT WEEK AT THE EARLIEST.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 653 AM CST SAT NOV 15 2014
SATELLITE AND SURFACE OBSERVATIONS CONTINUE TO SHOW MVFR CIGS
ENTERING WESTERN AND PORTIONS OF SOUTH CENTRAL NORTH DAKOTA THIS
MORNING. THIS IS FORECAST TO PERSIST INTO THE EARLY AFTERNOON.
CIGS AT KDIK WILL FREQUENTLY VARY BETWEEN MVFR/IFR...WHILE MVFR
CIGS WILL CONTINUE TO FILL IN AT KBIS BY 13Z...AND INTO KMOT BY
16Z. KJMS WILL REMAIN VFR TODAY WITH MVFR CIGS SOUTH OF THE
TERMINAL.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
WIND CHILL ADVISORY UNTIL 10 AM CST /9 AM MST/ THIS MORNING FOR
NDZ001-009-017-018-031>033.
&&
$$
UPDATE...AYD
SHORT TERM...KS
LONG TERM...AYD
AVIATION...KS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
406 AM CST SAT NOV 15 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 406 AM CST SAT NOV 15 2014
MAIN HIGHLIGHT THIS MORNING IS A WIND CHILL ADVISORY FOR PORTIONS OF
THE FAR WEST. COLDER AIR COMING IN FROM THE WEST AND BRISK WINDS
WILL DOMINATE THROUGH MID MORNING. A POTENT SHORTWAVE AND ASSOCIATED
COLD FRONT SHIFTING SOUTH FROM CENTRAL CANADA WILL BEGIN TO IMPACT
WESTERN/NORTHERN NORTH DAKOTA LATE SATURDAY NIGHT THEN SPREAD SOUTH
SUNDAY MORNING.
THE LATEST WATER VAPOR IMAGERY SHOWS AN ELONGATED UPPER TROUGH
FROM HUDSON BAY SOUTHWEST INTO MONTANA. AHEAD OF THE TROUGH...A
SHORTWAVE WAS SEEN ALONG THE WYOMING/MONTANA BORDER MOVING EAST TO
SOUTHEAST WITH TIME...AS THE SURFACE LOW REMAINS FARTHER SOUTH.
LIGHT SNOW ASSOCIATED WITH THIS SYSTEM EXTENDED ACROSS CENTRAL AND
SOUTHERN SOUTH DAKOTA AND IS MOVING EAST. FARTHER UPSTREAM...AN
AREA OF STRATUS OVER SOUTHERN SASKATCHEWAN PER LATEST FOG/STRATUS
LOOP CONTINUES A SOUTHEAST MOVEMENT. THE HRRR AND RAP13 SHIFT THIS
INTO NORTHWEST AND NORTH CENTRAL NORTH DAKOTA BETWEEN 12Z-21Z
TODAY. CONCUR WITH THIS AND ADJUSTED SKY GRIDS ACCORDINGLY.
ELSEWHERE ISOLATED FLURRIES WITH POCKETS OF STRATUS CONTINUE EARLY
THIS MORNING IN THE FAR SOUTHWEST...ALONG AND SOUTH OF LAKE
SAKAKAWEA...AND IN THE SOUTHERN JAMES RIVER VALLEY. ANOTHER VERY
COLD DAY AHEAD WITH HIGHS IN THE SINGLE DIGITS ABOVE ZERO IN THE
WEST AND SOUTHWEST...TO LOWER/MIDDLE TEENS ELSEWHERE. BRISK
NORTHWEST WINDS THIS AFTERNOON 10 TO 25 MPH.
FOR TONIGHT...ATTENTION TURNS TO A STRONG SHORTWAVE TROUGH AND
ASSOCIATED SHARP COLD FRONT HEADING DUE SOUTH FROM THE NORTHWEST
TERRITORIES. THE COLD FRONT WILL PASS THROUGH NORTHWEST AND NORTH
CENTRAL AFTER MIDNIGHT WITH INCREASING WINDS TOWARD AND SHORTLY
AFTER DAYBREAK ON SUNDAY.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 406 AM CST SAT NOV 15 2014
BLOWING SNOW POTENTIAL ON SUNDAY HIGHLIGHTS THE EXTENDED FORECAST.
THE 00 UTC GUIDANCE SUITE CONTINUES THE TREND OVER THE PAST
SEVERAL DAYS OF A REINFORCING COLD FRONT TO PROPAGATE ACROSS
WESTERN AND CENTRAL NORTH DAKOTA SUNDAY MORNING IN ASSOCIATION
WITH ITS PARENT CLIPPER SYSTEM ACROSS EASTERN MANITOBA INTO
WESTERN ONTARIO. STRONG NORTHWEST WINDS INTERACTING WITH THE
SNOWFALL FROM LAST WEEKEND PRESENTS A BLOWING SNOW THREAT. THE
CHALLENGE IS IF BLIZZARD CRITERIA WILL BE MET ACROSS THE SOUTHWEST
WHERE THE MOST SNOW WAS RECEIVED. THE SNOW HAS BEEN ON THE GROUND
FOR A WEEK...HOWEVER...IT IS UNCRUSTED AND HAS NOT BEEN
SIGNIFICANTLY COMPACTED. THAT SAID....BEING THE FIRST SNOWFALL OF
THE SEASON...SOME OF THE SNOW MAY BE ADVERSE TO BEING LOFTED FROM
BEING TRAPPED IN THE GRASSES. THUS...WILL FORGO A BLIZZARD WATCH
FOR NOW...AND HIGHLIGHT THE THREAT WITH NEAR-BLIZZARD CONDITIONS
POSSIBLE IN THE REMAINDER OF THE PRODUCT SUITE AND SPECIAL WEATHER
STATEMENT. PROBABILITIES FOR HALF-MILE VISIBILITIES USING THE
BAGGLEY BLOWING SNOW MODEL TAKING INTO ACCOUNT SNOW AGE AND THE
LACK OF SIGNIFICANT FALLING SNOW PRODUCE RESULTS THAT DO NOT FAVOR
BLIZZARD CRITERIA BEING MET. FURTHERMORE...THE STRENGTH OF
ISALLOBARIC FORCING AND WINDS AT THE TOP OF THE MIXED LAYER
DECREASE THROUGH THE DAY...BEING GREATEST PRIOR TO THE PRE-FRONTAL
INVERSION BEING BROKEN. CERTAINLY AT LEAST A WINTER WEATHER
ADVISORY FOR BLOWING SNOW WILL BE NEEDED FOR THE SOUTHWEST...AND
POSSIBLY INTO THE SOUTH CENTRAL. GIVEN FURTHER EVALUATION
TODAY.... WOULD NOT BE SURPRISED IF A BLIZZARD WATCH IS ISSUED.
THEREAFTER...THE DE-AMPLIFICATION OF THE ANOMALOUS UPPER LEVEL
PATTERN IS SLOWER WITH THE 15/00 UTC GUIDANCE CONSENSUS COMPARED
TO PREVIOUS RUNS...WITH A RECOVERY FROM ARCTIC AIR LIKELY DELAYED
UNTIL LATE NEXT WEEK AT THE EARLIEST.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 406 AM CST SAT NOV 15 2014
AN AREA OF MVFR CIGS OVER SASKATCHEWAN AND NORTHEAST MONTANA
CONTINUE TO SHIFT SOUTHEAST TOWARD KISN EARLY THIS MORNING. EXPECT
MVFR CIGS INTO KISN BETWEEN 10Z-12Z SATURDAY...AND INTO KMOT BY 15Z
SATURDAY. ELSEWHERE...POCKETS OF LOW VFR CIGS WILL CONTINUE OVER
KJMS THROUGH THE EARLY MORNING...WITH KDIK DETERIORATING FROM VFR TO
MVFR/IFR.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
WIND CHILL ADVISORY UNTIL 10 AM CST /9 AM MST/ THIS MORNING FOR
NDZ001-009-017-018-031>033.
&&
$$
SHORT TERM...KS
LONG TERM...AYD
AVIATION...KS
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
846 AM EST SAT NOV 15 2014
.SYNOPSIS...
HIGH PRESSURE LINGERS TODAY. NEXT SYSTEM WITH DEEPER MOISTURE
SUNDAY NIGHT INTO MONDAY. REINFORCING COLD AIR ARRIVES MONDAY
NIGHT INTO TUESDAY. COLDEST DAY TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
845 AM UPDATE...NO MAJOR CHANGES NEEDED. DID HIT RECORD OR NEAR
RECORD LOWS FOR MUCH OF THE AREA THIS MORNING.
PREVIOUS DISCUSSION BELOW...
STRATUS HANGING TOUGH OVER THE N MOUNTAINS ATTM WHICH IS KEEPING
TEMPS UP AT EKN COMPARED A HAIR. EXPECT THESE CLOUDS TO DISSIPATE
PER HRRR OVER THE NEXT SEVERAL HRS. ELSEWHERE...QUITE COLD WITH
TEMPS RUNNING A BIT BLOW FCST CURVE IN THE OUTLYING AREAS.
ADJUSTED HOURLY TEMPS AND MINT GRID DOWN A FEW
DEGREES...ESPECIALLY AWAY FROM URBAN CENTERS. MID TEENS LOOK LIKE
A GOOD BET ACROSS THESE LOCATIONS ACROSS THE LOWLANDS. IF THE
CLOUDS OVER THE MOUNTAINS CAN CLEAR IN TIME...THEN SOME HIGH
SINGLE NUMBERS ARE POSSIBLE OVER THE HIGH RIDGES. SNOWSHOE
CURRENTLY SITTING AT 11F.
AS FOR TODAY...THE SUN WILL FINALLY MAKE AN APPEARANCE...ALBEIT
WITH A SHORT STAY. SOME CIRRUS WILL STREAK IN DURING THE FIRST
HALF OF TODAY...FOLLOWED BY INCREASE IN MID LEVEL CLOUDS
ASSOCIATED WAA ALOFT LATE IN THE AFTERNOON AND EARLY EVENING /FROM
SW TO NE/. H85 TEMPS WILL MODERATE BY ALMOST 10 DEGREES TODAY.
STILL...WITH H925 TEMPS STILL ON THE COOL SIDE...FELT ROLLING WITH
COOLER GUIDANCE /A LA LOCAL IN HOUSE MOS/ WAS THE BEST OPTION. AS
SUCH...HAVE SOME MID 30S FOR THE LOWLANDS WITH LOWER 30S FOR THE
HIGH TERRAIN. BIGGEST IMPROVEMENT IN TEMPS COMPARED TO YESTERDAY
WILL BE FELT IN THE HIGHER ELEVATIONS WHERE SNOWSHOE SHOULD MAKE A
RUN TOWARD UPPER 20S LATE IN THE DAY VERSUS LOW TEENS OBSERVED YESTERDAY.
A MID LEVEL DISTURBANCE WILL RACE THROUGH THE REGION TONIGHT.
HOWEVER...WITH LITTLE FANFARE OTHER THAN THE INCREASE IN MIDDLE
LEVEL CLOUDS. THE WAA ALOFT CONTINUES THOUGH...SO HAVE HIGHEST
RIDGES HOLDING NEAR STEADY IF NOT RISING TOWARD MORNING WITH
GENERALLY MID 20S IN THE LOWLANDS.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY NIGHT/...
A WAVE MOVING ACROSS SATURDAY NIGHT INTO SUNDAY SUFFERS FROM LACK OF
LOW LEVEL MOISTURE. SHOULD SEE LOTS OF VIRGA...BUT QUESTIONABLE HOW
MUCH MAKES IT TO THE GROUND. WILL KEEP POPS IN THE SLIGHT
CHANCE/CHANCE CATEGORIES...SLOWING INCREASING AS THE COLUMN TRIES TO
SATURATE.
MAIN SYSTEM OF INTEREST ARRIVES SUNDAY NIGHT AND CONTINUES INTO
MONDAY. SREF/NAM/ECMWF ARE THE WARMEST OF THE MODELS...WITH THE GFS
AND CANADIAN ON THE COOLER SIDE. WILL RUN IN BETWEEN THE 2 CAMPS FOR
NOW...KEEPING A BAND OF PRECIPITATION IN THE MIDDLE THAT COULD BE
EITHER RAIN OR SNOW. THIS BASICALLY KEEPS MOST OF WV AND VA AS
RAIN...WITH A TRANSITION ZONE ACROSS NORTHEAST KY/SOUTHEAST OH AND
FAR NW WV. CENTRAL OH HAS THE BEST CHANCE OF BEING ALL SNOW.
THE TIMING OF THE TRANSITION TO SNOW IS ALSO UP FOR DEBATE ON MONDAY
WITH TIMING DIFFERENCES BETWEEN THE MODELS. WILL GO BELOW MOS
GUIDANCE OF HIGHS ON MONDAY DUE TO FALLING PRECIPITATION.
&&
.LONG TERM /WEDNESDAY THROUGH FRIDAY/...
THE SUPPORT FROM THE STRENGTHENING 250 MB JET SHOULD BE TO OUR EAST
BY MONDAY EVENING...WITH THE REINFORCING COLD ARCTIC AIR BLOWING
IN.
LIKE YESTERDAY AND THE DAY BEFORE THAT...WE WILL CONTINUE TO HOLD
ONTO TO HIGHER POPS LONGER IN SOME ACCUMULATING SNOW SHOWERS MONDAY
EVENING THAN MODEL GUIDANCE....AS DEW POINTS LOWER IN THE COLD AIR
ADVECTION.
DRIER ARCTIC AIR TAKES CONTROL FOR TUESDAY WITH LOW DEW POINTS. SO
DESPITE THE 850 MB THERMAL TROF...DO NOT WANT TO BE AS PESSIMISTIC
AS WE USUALLY ARE ON CLOUDS IN THE LOW LEVEL THERMAL TROF.
YET...STILL LEFT SOME FLAKES IN THE AIR WELL THROUGH TUESDAY NIGHT
FOR THE MOUNTAIN COUNTIES.
COLDEST DAY MAXIMUM READINGS SHOULD BE TUESDAY. MOST LOWLAND
READINGS IN THE 20S FOR MAXIMUM. OUR SMALL AREA AOA 4000 FEET SHOULD
REMAIN IN SINGLE DIGITS DURING THE DAY ON TUESDAY.
AN IDEAL CLEAR/CALM NIGHT MAY BE HARD TO FIND...SINCE HIGH PRESSURE
CENTER NOT DIRECTLY OVER US. BUT WINDS SHOULD DIMINISH TUESDAY
NIGHT. SO COLDEST TEMPERATURES FOR LOWLANDS LIKELY TUESDAY
NIGHT/EARLY WEDNESDAY.
CONTINUED DRY WEDNESDAY INTO THURSDAY.
WARM AIR ADVECTION MOISTURE INCREASES THURSDAY NIGHT INTO FRIDAY.
WILL HAVE CHANCE POPS SPREADING SW TO NE OVERNIGHT THURSDAY NIGHT
INTO FRIDAY.
&&
.AVIATION /14Z SATURDAY THROUGH WEDNESDAY/...
VFR CONDITIONS WILL PREVAIL THROUGH THE TAF PERIOD EXCEPT FOR SOME
LINGERING MVFR CIGS OVER KEKN EARLY THIS MORNING. AN INCREASE IN
HIGH AND MIDDLE LEVEL CLOUDS CAN BE EXPECTED AS THE DAY
PROGRESSES. THIS TREND CONTINUES TONIGHT WITH PASSAGE OF AN UPPER
LEVEL DISTURBANCE.
FLOW SURFACE AND ALOFT WILL BE LIGHT TODAY COURTESY OF HIGH
PRESSURE. FLOW ALOFT INCREASES OUT OF SW 20 TO 25 KTS TONIGHT BUT
SURFACE WINDS ACROSS TAF SITES WILL REMAIN LIGHT.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z SUNDAY...
FORECAST CONFIDENCE: HIGH
ALTERNATE SCENARIOS: NONE
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01
EST 1HRLY 09 10 11 12 13 14 15 16 17 18 19 20
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 12Z SUNDAY...
IFR POSSIBLE SUNDAY NIGHT INTO TUESDAY IN PRECIPITATION AND
CLOUDS.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...KTB/RPY/30
NEAR TERM...SL/30
SHORT TERM...RPY
LONG TERM...KTB
AVIATION...30
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
543 AM EST SAT NOV 15 2014
.SYNOPSIS...
HIGH PRESSURE LINGERS TODAY. NEXT SYSTEM WITH DEEPER MOISTURE
SUNDAY NIGHT INTO MONDAY. REINFORCING COLD AIR ARRIVES MONDAY
NIGHT INTO TUESDAY. COLDEST DAY TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
640 AM UPDATE...
NO CHANGES ATTM. LOWEST TEMP I COULD FIND AT THIS HOUR WAS AN
UNOFFICIAL OBSERVATION OF 8 DEGREES UP A HOLLOW NEAR TOWN OF BOLT
IN SW RALEIGH COUNTY. BRRR.
PREVIOUS DISCUSSION BELOW...
STRATUS HANGING TOUGH OVER THE N MOUNTAINS ATTM WHICH IS KEEPING
TEMPS UP AT EKN COMPARED A HAIR. EXPECT THESE CLOUDS TO DISSIPATE
PER HRRR OVER THE NEXT SEVERAL HRS. ELSEWHERE...QUITE COLD WITH
TEMPS RUNNING A BIT BLOW FCST CURVE IN THE OUTLYING AREAS.
ADJUSTED HOURLY TEMPS AND MINT GRID DOWN A FEW
DEGREES...ESPECIALLY AWAY FROM URBAN CENTERS. MID TEENS LOOK LIKE
A GOOD BET ACROSS THESE LOCATIONS ACROSS THE LOWLANDS. IF THE
CLOUDS OVER THE MOUNTAINS CAN CLEAR IN TIME...THEN SOME HIGH
SINGLE NUMBERS ARE POSSIBLE OVER THE HIGH RIDGES. SNOWSHOE
CURRENTLY SITTING AT 11F.
AS FOR TODAY...THE SUN WILL FINALLY MAKE AN APPEARANCE...ALBEIT
WITH A SHORT STAY. SOME CIRRUS WILL STREAK IN DURING THE FIRST
HALF OF TODAY...FOLLOWED BY INCREASE IN MID LEVEL CLOUDS
ASSOCIATED WAA ALOFT LATE IN THE AFTERNOON AND EARLY EVENING /FROM
SW TO NE/. H85 TEMPS WILL MODERATE BY ALMOST 10 DEGREES TODAY.
STILL...WITH H925 TEMPS STILL ON THE COOL SIDE...FELT ROLLING WITH
COOLER GUIDANCE /A LA LOCAL IN HOUSE MOS/ WAS THE BEST OPTION. AS
SUCH...HAVE SOME MID 30S FOR THE LOWLANDS WITH LOWER 30S FOR THE
HIGH TERRAIN. BIGGEST IMPROVEMENT IN TEMPS COMPARED TO YESTERDAY
WILL BE FELT IN THE HIGHER ELEVATIONS WHERE SNOWSHOE SHOULD MAKE A
RUN TOWARD UPPER 20S LATE IN THE DAY VERSUS LOW TEENS OBSERVED YESTERDAY.
A MID LEVEL DISTURBANCE WILL RACE THROUGH THE REGION TONIGHT.
HOWEVER...WITH LITTLE FANFARE OTHER THAN THE INCREASE IN MIDDLE
LEVEL CLOUDS. THE WAA ALOFT CONTINUES THOUGH...SO HAVE HIGHEST
RIDGES HOLDING NEAR STEADY IF NOT RISING TOWARD MORNING WITH
GENERALLY MID 20S IN THE LOWLANDS.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY NIGHT/...
A WAVE MOVING ACROSS SATURDAY NIGHT INTO SUNDAY SUFFERS FROM LACK OF
LOW LEVEL MOISTURE. SHOULD SEE LOTS OF VIRGA...BUT QUESTIONABLE HOW
MUCH MAKES IT TO THE GROUND. WILL KEEP POPS IN THE SLIGHT
CHANCE/CHANCE CATEGORIES...SLOWING INCREASING AS THE COLUMN TRIES TO
SATURATE.
MAIN SYSTEM OF INTEREST ARRIVES SUNDAY NIGHT AND CONTINUES INTO
MONDAY. SREF/NAM/ECMWF ARE THE WARMEST OF THE MODELS...WITH THE GFS
AND CANADIAN ON THE COOLER SIDE. WILL RUN IN BETWEEN THE 2 CAMPS FOR
NOW...KEEPING A BAND OF PRECIPITATION IN THE MIDDLE THAT COULD BE
EITHER RAIN OR SNOW. THIS BASICALLY KEEPS MOST OF WV AND VA AS
RAIN...WITH A TRANSITION ZONE ACROSS NORTHEAST KY/SOUTHEAST OH AND
FAR NW WV. CENTRAL OH HAS THE BEST CHANCE OF BEING ALL SNOW.
THE TIMING OF THE TRANSITION TO SNOW IS ALSO UP FOR DEBATE ON MONDAY
WITH TIMING DIFFERENCES BETWEEN THE MODELS. WILL GO BELOW MOS
GUIDANCE OF HIGHS ON MONDAY DUE TO FALLING PRECIPITATION.
&&
.LONG TERM /WEDNESDAY THROUGH FRIDAY/...
THE SUPPORT FROM THE STRENGTHENING 250 MB JET SHOULD BE TO OUR EAST
BY MONDAY EVENING...WITH THE REINFORCING COLD ARCTIC AIR BLOWING
IN.
LIKE YESTERDAY AND THE DAY BEFORE THAT...WE WILL CONTINUE TO HOLD
ONTO TO HIGHER POPS LONGER IN SOME ACCUMULATING SNOW SHOWERS MONDAY
EVENING THAN MODEL GUIDANCE....AS DEW POINTS LOWER IN THE COLD AIR
ADVECTION.
DRIER ARCTIC AIR TAKES CONTROL FOR TUESDAY WITH LOW DEW POINTS. SO
DESPITE THE 850 MB THERMAL TROF...DO NOT WANT TO BE AS PESSIMISTIC
AS WE USUALLY ARE ON CLOUDS IN THE LOW LEVEL THERMAL TROF.
YET...STILL LEFT SOME FLAKES IN THE AIR WELL THROUGH TUESDAY NIGHT
FOR THE MOUNTAIN COUNTIES.
COLDEST DAY MAXIMUM READINGS SHOULD BE TUESDAY. MOST LOWLAND
READINGS IN THE 20S FOR MAXIMUM. OUR SMALL AREA AOA 4000 FEET SHOULD
REMAIN IN SINGLE DIGITS DURING THE DAY ON TUESDAY.
AN IDEAL CLEAR/CALM NIGHT MAY BE HARD TO FIND...SINCE HIGH PRESSURE
CENTER NOT DIRECTLY OVER US. BUT WINDS SHOULD DIMINISH TUESDAY
NIGHT. SO COLDEST TEMPERATURES FOR LOWLANDS LIKELY TUESDAY
NIGHT/EARLY WEDNESDAY.
CONTINUED DRY WEDNESDAY INTO THURSDAY.
WARM AIR ADVECTION MOISTURE INCREASES THURSDAY NIGHT INTO FRIDAY.
WILL HAVE CHANCE POPS SPREADING SW TO NE OVERNIGHT THURSDAY NIGHT
INTO FRIDAY.
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
VFR CONDITIONS WILL PREVAIL THROUGH THE TAF PERIOD EXCEPT FOR SOME
LINGERING MVFR CIGS OVER KEKN EARLY THIS MORNING. AN INCREASE IN
HIGH AND MIDDLE LEVEL CLOUDS CAN BE EXPECTED AS THE DAY
PROGRESSES. THIS TREND CONTINUES TONIGHT WITH PASSAGE OF AN UPPER
LEVEL DISTURBANCE.
FLOW SURFACE AND ALOFT WILL BE LIGHT TODAY COURTESY OF HIGH
PRESSURE. FLOW ALOFT INCREASES OUT OF SW 20 TO 25 KTS TONIGHT BUT
SURFACE WINDS ACROSS TAF SITES WILL REMAIN LIGHT.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z SUNDAY...
FORECAST CONFIDENCE: HIGH
ALTERNATE SCENARIOS: NONE
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 11 12 13 14 15 16 17 18 19 20 21 22
EST 1HRLY 06 07 08 09 10 11 12 13 14 15 16 17
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 12Z SUNDAY...
IFR POSSIBLE SUNDAY NIGHT INTO TUESDAY IN PRECIPITATION AND
CLOUDS.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...KTB/RPY/30
NEAR TERM...30
SHORT TERM...RPY
LONG TERM...KTB
AVIATION...30
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
535 AM CST SAT NOV 15 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 415 AM CST SAT NOV 15 2014
FOCUS ON THE SNOW EVENT CURRENTLY UNDERWAY ACROSS OUR WESTERN
CWA... EXPECTED TO PROGRESS EAST THROUGH THE REGION OVER THE
NEXT 24 HOURS. OVERALL LOOKING AT A BROAD ISENTROPIC UPGLIDE
AHEAD OF OPEN WAVE...WHICH SHOULD RESULT IN FAIRLY UNIFORM SNOW
AMOUNTS ACROSS THE REGION. HOWEVER...CURRENT RADAR SHOWING A COUPLE
MORE DISTINCT BANDS NEAR MID LEVEL /750-650MB/ FRONTAL BOUNDARIES
PER RAP MODEL...SO COULD SEE SOME AREAS OF ENHANCEMENT THROUGHOUT
THE DAY. FRONTOGENESIS APPEARS TO BE FAIRLY TRANSIENT THOUGH...SO DO
NOT EXPECT HEAVIER BANDS TO SIT IN ANY ONE LOCATION FOR PROLONGED
PERIOD OF TIME. NORTHERN BAND APPEARS TO BE A LITTLE FARTHER NORTH
THAN PREVIOUSLY EXPECTED THOUGH...AIMING TOWARD THE HIGHWAY 14
CORRIDOR THROUGH THE MORNING. HAVE BUMPED UP SNOW AMOUNTS A BIT IN
THESE AREAS AS A RESULT...AND EXPANDED ADVISORY NORTHWARD TO COVER
ENTIRE CWA FOR WIDESPREAD 3 TO 5 INCHES.
IN ADDITION TO POTENTIALLY HIGHER BANDS...CONCERN FOR THIS EVENT IS
HIGH SNOW RATIOS GIVEN STRONG LIFT WITHIN DEEP DENDRITIC LAYER...
AND LIGHT WINDS ALLOWING DENDRITIC SNOW FLAKES TO HOLD TOGETHER.
GENERALLY STICKING WITH 16-18:1 RATIOS FOR BULK OF THE SNOWFALL...
BUT SOME MODELS INDICATE A BIT HIGHER...WHICH COULD PUSH AMOUNTS
CLOSER TO 6 INCH RANGE IN SOME AREAS. STILL EXPECT SNOW TO BE DONE
IN MOST AREAS BY MID-LATE EVENING...BUT WAVE IS A BIT SLOWER IN
DEPARTING THIS EVENING...SO EXTENDED ADVISORY TIMING IN OUR FAR
EAST THROUGH MIDNIGHT TONIGHT. GIVEN FLUFFY NATURE OF SNOWFALL...
COULD SEE A LITTLE BLOWING/DRIFTING OF FRESH SNOW AS NORTHWEST WINDS
PICK UP BEHIND THE FRONT ACROSS OUR SOUTHWEST AREAS THIS AFTERNOON
AND EVENING...AND WILL CONTINUE MENTION OF PATCHY BLOWING SNOW
THROUGH PARTS OF THE MISSOURI RIVER VALLEY. STRONGER WINDS OCCUR
AFTER BULK OF ACCUMULATION IS OVER THOUGH...SO AT THIS TIME HAVE NOT
EXTENDED HEADLINES TO COVER ANY BLOWING SNOW THREAT.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 415 AM CST SAT NOV 15 2014
ON SUNDAY...INTENSIFYING LOW PRESSURE TRACKING THROUGH THE UPPER
MISSISSIPPI VALLEY/WESTERN GREAT LAKES REGION WILL PULL A COLD FRONT
THROUGH OUR AREA IN THE AFTERNOON. WHILE WINDS WILL INITIALLY BE OUT
OF THE WEST/SOUTHWEST EARLY IN THE DAY...THEY WILL TURN AROUND TO
THE NORTHWEST WITH THE PASSAGE OF THE SYSTEM...AND PICK UP IN A COLD
AIR ADVECTION REGIME. WITH THIS...GUSTS WILL RAMP UP TO 20 TO 30 KTS
ACROSS THE AREA. IN RESPONSE TO THIS...WILL BEGIN TO HAVE AREAS OF
BLOWING SNOW WITH FRESH SNOW COVER ON THE GROUND. WILL ALSO SEE THE
POSSIBILITY OF SCATTERED FLURRIES OVER PORTIONS OF THE AREA WITH
SOME CLOUD COVER AND VERY COLD THERMAL PROFILES SUPPORTIVE OF
DENDRITIC GROWTH. IN A THE WEST/SOUTHWESTERLY FLOW OUT AHEAD OF THE
FRONT...THE MISSOURI RIVER VALLEY WILL HAVE THE OPPORTUNITY TO WARM
INTO THE MID 20S BEFORE BEGINNING TO DROP OFF IN THE AFTERNOON AS
THE COLDER AIR FEEDS INTO THE AREA. BACK TO THE NORTH AND
EAST...HIGHS WILL ONLY MAKE IT INTO THE UPPER TEENS TO LOWER 20S.
STRONG GUSTY NORTHWESTERLY WINDS WILL PERSIST FOR SUNDAY NIGHT AND
MONDAY...KEEPING THE POSSIBILITY OF BLOWING SNOW ACROSS THE AREA
THROUGH THE PERIOD. THE WINDS WILL KEEP TEMPERATURES FROM DROPPING
OFF TOO DRAMATICALLY ON SUNDAY NIGHT...THOUGH STILL COLD WITH LOWS
IN THE SINGLE DIGITS. IN AN INCREASINGLY COLD AIRMASS WITH MONDAY
925 MB TEMPERATURES PROGGED TO BE JUST EITHER SIDE OF -15 C...IT
WILL BE A BITTERLY COLD DAY WITH HIGHS IN THE LOWER TO MID TEENS.
WITH THE AFOREMENTIONED WINDS...WIND CHILLS WILL BE FIERCE...RUNNING
IN THE SINGLE DIGITS BELOW ZERO TO TEENS BELOW ZERO.
WINDS WILL THEN RAMP DOWN ON MONDAY NIGHT AS A SURFACE RIDGE AXIS
SLIDES CLOSER TO THE AREA...BRINGING AN END TO ANY BLOWING SNOW.
STILL ENOUGH WIND HOWEVER TO KEEP OVERNIGHT LOWS SOMEWHAT IN
CHECK...BOTTOMING OUT JUST EITHER SIDE OF ZERO.
FOR THE REMINDER OF NEXT WEEK...THERE WILL BE A SLIGHT MODERATION OF
TEMPERATURES...ALBEIT STILL MUCH BELOW NORMAL...IN A NORTHWESTERLY
UPPER LEVEL FLOW. THIS WOULD BE MOST APPARENT TOWARD THE END OF THE
WEEK WHEN HIGHS ON FRIDAY COULD CLOSE IN ON THE LOWER 30S THROUGH
THE MISSOURI RIVER VALLEY. THERE DOES NOT APPEAR TO BE ANY
SIGNIFICANT PRECIPITATION PRODUCERS THROUGH THE PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 535 AM CST SAT NOV 15 2014
WIDESPREAD MVFR-IFR CONDITIONS EXPECTED TODAY WITH SNOW MOVING
THROUGH THE REGION. CONDITIONS SHOULD GRADUALLY IMPROVE WEST TO
EAST AFTER 16/00Z AS SNOW COMES TO AN END BEHIND DEPARTING UPPER
WAVE AND ASSOCIATED FRONT. WINDS GENERALLY AT OR BELOW 10KT WITH
THE SNOW...BUT EXPECTED TO INCREASE WITH GUSTS 15-25KT AS WINDS
BECOME NORTHWESTERLY IN THE LATE AFTERNOON/EVENING. GUSTY WINDS
WILL LIKELY CREATE DRIFTING ACROSS RUNWAYS...AND COULD PRODUCE
LINGERING MVFR VISIBILITY IN BLOWING SNOW AT TIMES.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...WINTER WEATHER ADVISORY UNTIL 9 PM CST THIS EVENING FOR SDZ039-
040-054>056-060>062-065>071.
WINTER WEATHER ADVISORY UNTIL 3 PM CST THIS AFTERNOON FOR SDZ038-
050-052-053-057>059-063-064.
MN...WINTER WEATHER ADVISORY UNTIL 9 PM CST THIS EVENING FOR MNZ071-
072-080-089-097-098.
WINTER WEATHER ADVISORY FROM 9 AM THIS MORNING TO MIDNIGHT CST
TONIGHT FOR MNZ081-090.
IA...WINTER WEATHER ADVISORY UNTIL 9 PM CST THIS EVENING FOR IAZ001-
012-020-031.
WINTER WEATHER ADVISORY FROM 9 AM THIS MORNING TO MIDNIGHT CST
TONIGHT FOR IAZ002-003-013-014-021-022-032.
NE...WINTER WEATHER ADVISORY UNTIL 9 PM CST THIS EVENING FOR NEZ013-
014.
&&
$$
SHORT TERM...JH
LONG TERM...JM
AVIATION...JH
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
415 AM CST SAT NOV 15 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 415 AM CST SAT NOV 15 2014
FOCUS ON THE SNOW EVENT CURRENTLY UNDERWAY ACROSS OUR WESTERN
CWA... EXPECTED TO PROGRESS EAST THROUGH THE REGION OVER THE
NEXT 24 HOURS. OVERALL LOOKING AT A BROAD ISENTROPIC UPGLIDE
AHEAD OF OPEN WAVE...WHICH SHOULD RESULT IN FAIRLY UNIFORM SNOW
AMOUNTS ACROSS THE REGION. HOWEVER...CURRENT RADAR SHOWING A COUPLE
MORE DISTINCT BANDS NEAR MID LEVEL /750-650MB/ FRONTAL BOUNDARIES
PER RAP MODEL...SO COULD SEE SOME AREAS OF ENHANCEMENT THROUGHOUT
THE DAY. FRONTOGENESIS APPEARS TO BE FAIRLY TRANSIENT THOUGH...SO DO
NOT EXPECT HEAVIER BANDS TO SIT IN ANY ONE LOCATION FOR PROLONGED
PERIOD OF TIME. NORTHERN BAND APPEARS TO BE A LITTLE FARTHER NORTH
THAN PREVIOUSLY EXPECTED THOUGH...AIMING TOWARD THE HIGHWAY 14
CORRIDOR THROUGH THE MORNING. HAVE BUMPED UP SNOW AMOUNTS A BIT IN
THESE AREAS AS A RESULT...AND EXPANDED ADVISORY NORTHWARD TO COVER
ENTIRE CWA FOR WIDESPREAD 3 TO 5 INCHES.
IN ADDITION TO POTENTIALLY HIGHER BANDS...CONCERN FOR THIS EVENT IS
HIGH SNOW RATIOS GIVEN STRONG LIFT WITHIN DEEP DENDRITIC LAYER...
AND LIGHT WINDS ALLOWING DENDRITIC SNOW FLAKES TO HOLD TOGETHER.
GENERALLY STICKING WITH 16-18:1 RATIOS FOR BULK OF THE SNOWFALL...
BUT SOME MODELS INDICATE A BIT HIGHER...WHICH COULD PUSH AMOUNTS
CLOSER TO 6 INCH RANGE IN SOME AREAS. STILL EXPECT SNOW TO BE DONE
IN MOST AREAS BY MID-LATE EVENING...BUT WAVE IS A BIT SLOWER IN
DEPARTING THIS EVENING...SO EXTENDED ADVISORY TIMING IN OUR FAR
EAST THROUGH MIDNIGHT TONIGHT. GIVEN FLUFFY NATURE OF SNOWFALL...
COULD SEE A LITTLE BLOWING/DRIFTING OF FRESH SNOW AS NORTHWEST WINDS
PICK UP BEHIND THE FRONT ACROSS OUR SOUTHWEST AREAS THIS AFTERNOON
AND EVENING...AND WILL CONTINUE MENTION OF PATCHY BLOWING SNOW
THROUGH PARTS OF THE MISSOURI RIVER VALLEY. STRONGER WINDS OCCUR
AFTER BULK OF ACCUMULATION IS OVER THOUGH...SO AT THIS TIME HAVE NOT
EXTENDED HEADLINES TO COVER ANY BLOWING SNOW THREAT.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 415 AM CST SAT NOV 15 2014
ON SUNDAY...INTENSIFYING LOW PRESSURE TRACKING THROUGH THE UPPER
MISSISSIPPI VALLEY/WESTERN GREAT LAKES REGION WILL PULL A COLD FRONT
THROUGH OUR AREA IN THE AFTERNOON. WHILE WINDS WILL INITIALLY BE OUT
OF THE WEST/SOUTHWEST EARLY IN THE DAY...THEY WILL TURN AROUND TO
THE NORTHWEST WITH THE PASSAGE OF THE SYSTEM...AND PICK UP IN A COLD
AIR ADVECTION REGIME. WITH THIS...GUSTS WILL RAMP UP TO 20 TO 30 KTS
ACROSS THE AREA. IN RESPONSE TO THIS...WILL BEGIN TO HAVE AREAS OF
BLOWING SNOW WITH FRESH SNOW COVER ON THE GROUND. WILL ALSO SEE THE
POSSIBILITY OF SCATTERED FLURRIES OVER PORTIONS OF THE AREA WITH
SOME CLOUD COVER AND VERY COLD THERMAL PROFILES SUPPORTIVE OF
DENDRITIC GROWTH. IN A THE WEST/SOUTHWESTERLY FLOW OUT AHEAD OF THE
FRONT...THE MISSOURI RIVER VALLEY WILL HAVE THE OPPORTUNITY TO WARM
INTO THE MID 20S BEFORE BEGINNING TO DROP OFF IN THE AFTERNOON AS
THE COLDER AIR FEEDS INTO THE AREA. BACK TO THE NORTH AND
EAST...HIGHS WILL ONLY MAKE IT INTO THE UPPER TEENS TO LOWER 20S.
STRONG GUSTY NORTHWESTERLY WINDS WILL PERSIST FOR SUNDAY NIGHT AND
MONDAY...KEEPING THE POSSIBILITY OF BLOWING SNOW ACROSS THE AREA
THROUGH THE PERIOD. THE WINDS WILL KEEP TEMPERATURES FROM DROPPING
OFF TOO DRAMATICALLY ON SUNDAY NIGHT...THOUGH STILL COLD WITH LOWS
IN THE SINGLE DIGITS. IN AN INCREASINGLY COLD AIRMASS WITH MONDAY
925 MB TEMPERATURES PROGGED TO BE JUST EITHER SIDE OF -15 C...IT
WILL BE A BITTERLY COLD DAY WITH HIGHS IN THE LOWER TO MID TEENS.
WITH THE AFOREMENTIONED WINDS...WIND CHILLS WILL BE FIERCE...RUNNING
IN THE SINGLE DIGITS BELOW ZERO TO TEENS BELOW ZERO.
WINDS WILL THEN RAMP DOWN ON MONDAY NIGHT AS A SURFACE RIDGE AXIS
SLIDES CLOSER TO THE AREA...BRINGING AN END TO ANY BLOWING SNOW.
STILL ENOUGH WIND HOWEVER TO KEEP OVERNIGHT LOWS SOMEWHAT IN
CHECK...BOTTOMING OUT JUST EITHER SIDE OF ZERO.
FOR THE REMINDER OF NEXT WEEK...THERE WILL BE A SLIGHT MODERATION OF
TEMPERATURES...ALBEIT STILL MUCH BELOW NORMAL...IN A NORTHWESTERLY
UPPER LEVEL FLOW. THIS WOULD BE MOST APPARENT TOWARD THE END OF THE
WEEK WHEN HIGHS ON FRIDAY COULD CLOSE IN ON THE LOWER 30S THROUGH
THE MISSOURI RIVER VALLEY. THERE DOES NOT APPEAR TO BE ANY
SIGNIFICANT PRECIPITATION PRODUCERS THROUGH THE PERIOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1048 PM CST FRI NOV 14 2014
THROUGH 15Z CEILINGS AND VISIBILITIES WILL LOWER FROM THE WEST
FROM VFR TO AROUND 1K FEET AND BELOW 3SM IN SNOW. FROM 15/20Z TO
16/06Z CONDITIONS WILL IMPROVE SLOWLY FROM THE WEST TO CEILINGS
2-3K FEET AND VISIBILITY GREATER THAN 5SM AS SNOW ENDS. WEST OF A
BKX/FSD/SUX LINE...SKIES WILL CLEAR FROM THE WEST 16/00Z-06Z.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...WINTER WEATHER ADVISORY UNTIL 9 PM CST THIS EVENING FOR SDZ039-
040-054>056-060>062-065>071.
WINTER WEATHER ADVISORY UNTIL 3 PM CST THIS AFTERNOON FOR SDZ038-
050-052-053-057>059-063-064.
MN...WINTER WEATHER ADVISORY UNTIL 9 PM CST THIS EVENING FOR MNZ071-
072-080-089-097-098.
WINTER WEATHER ADVISORY FROM 9 AM THIS MORNING TO MIDNIGHT CST
TONIGHT FOR MNZ081-090.
IA...WINTER WEATHER ADVISORY UNTIL 9 PM CST THIS EVENING FOR IAZ001-
012-020-031.
WINTER WEATHER ADVISORY FROM 9 AM THIS MORNING TO MIDNIGHT CST
TONIGHT FOR IAZ002-003-013-014-021-022-032.
NE...WINTER WEATHER ADVISORY UNTIL 9 PM CST THIS EVENING FOR NEZ013-
014.
&&
$$
SHORT TERM...JH
LONG TERM...JM
AVIATION...
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
958 AM CST SAT NOV 15 2014
.UPDATE...
MID AND HIGH LEVEL CLOUDS WILL CONTINUE TO INCREASE FROM THE WEST
TODAY AS A SHORTWAVE APPROACHES. THE FORECAST SNOWFALL SEEMS TO BE
ON TRACK GIVEN UPSTREAM CONDITIONS AND THE 12Z NAM. LATEST NAM AND
RAP SOUNDINGS SUGGEST THE SNOW WILL START IN THE WEST BY 4 PM AND
IN THE EAST BY 6 PM. STILL LOOKS LIKE THE BULK OF SNOW WILL FALL
PRIOR TO MIDNIGHT...WITH SOME LINGERING LIGHT ACCUMULATIONS
THROUGH THE REMAINDER OF THE NIGHT. STORM TOTALS OF 1 TO 2 INCHES
STILL LOOKS ABOUT RIGHT.
&&
.AVIATION/18Z TAFS/...
MID AND HIGH LEVEL CLOUDS WILL CONTINUE TO INCREASE FROM THE WEST
TODAY AS A SHORTWAVE APPROACHES. LATEST NAM AND RAP SOUNDINGS
SUGGEST THE SNOW WILL START IN THE WEST BY 4 PM AND IN THE EAST BY
6 PM. STILL LOOKS LIKE THE BULK OF SNOW WILL FALL PRIOR TO
MIDNIGHT...WITH SOME LINGERING LIGHT ACCUMULATIONS THROUGH THE
REMAINDER OF THE NIGHT. STORM TOTALS OF 1 TO 2 INCHES STILL LOOKS
ABOUT RIGHT. IT WILL BE A DRY SNOW...WITH LIQUID TO SNOW RATIOS OF
AROUND 17 TO 1.
UPSTREAM OBS AND SOUNDINGS SUGGEST IFR/MVFR CIGS WITH THE
SNOWFALL...WITH VSBYS DROPPING TO 1 TO 2 MILES...POSSIBLY BRIEFLY
DOWN TO 1/2SM.
LOOKS LIKE MVFR CIGS MAY LINGER FOR MUCH OF SUNDAY...AS A SECOND
SHORTWAVE MOVES THROUGH WHILE A THIRD WAVE APPROACHES. WILL
PROBABLY SEE A LITTLE LIGHT SNOW AT TIMES SUNDAY...BUT NOT
EXPECTING ADDITIONAL ACCUMULATIONS.
&&
.PREV DISCUSSION... /ISSUED 330 AM CST SAT NOV 15 2014/
TODAY AND TONIGHT...FORECAST CONFIDENCE IS HIGH.
MID LEVEL CLOUDS OVER NRN IL AND WEST OF THE MS RIVER ASSOCIATED
WITH LEADING EDGE OF MID LEVEL WARM ADVECTION. WARM ADVECTION
PATTERN IS AHEAD OF A SHORTWAVE TROUGH OVER CO AND A STRONGER WAVE
OVER MT/IDAHO. THE CO SHORTWAVE WILL LIFT NEWD AND MOVE ACROSS SRN
WI THIS EVENING. WEAK MID LEVEL WARM ADVECTION AND FRONTOGENESIS
IS EXPECTED DURING THIS TIME BUT THE PVA IS MORE PRONOUNCED. THE
LARGER UPPER TROUGH WILL THEN MOVE INTO WEST CENTRAL WI BY 12Z SUN
BUT THE 500 MB DRY SLOT WILL KEEP THE SNOW VERY LIGHT.
THUS MOST OF THE SNOW ACCUMULATIONS WILL OCCUR FROM LATE THIS
AFTERNOON INTO THE EVENING HOURS. QPF TOTALS ARE RANGING FROM
0.08-0.12 INCHES WITH HIGH SNOW RATIOS DUE TO THE VERY COLD
TROPOSPHERE. SNOW TOTALS OF 1-2 INCHES ARE EXPECTED WITH THE
HIGHER VALUES OVER THE WRN CWA.
HIGH TEMPS TO REMAIN IN THE MID TO UPPER 20S TODAY WITH THE
INCREASING CLOUDS. THE CLOUDS...SNOW...AND WEAK WARM ADVECTION TNT
WILL KEEP TEMPS IN THE LOWER 20S FOR MOST OF THE NIGHT.
SHORT TERM...SUNDAY THROUGH MONDAY NIGHT...FORECAST CONFIDENCE IS
MEDIUM.
MODELS IN GOOD AGREEMENT WITH 500 MB VORTICITY MAXIMUM SLIDING
EAST ACROSS THE AREA DURING THE MORNING...THEN SLOWLY TO THE EAST
OF THE AREA IN THE AFTERNOON. AREA FORECAST SOUNDINGS SHOW ENOUGH
DEEP MOISTURE WITHIN DEEP DENDRITE SNOW GROWTH ZONE TO MAINTAIN
LOWER END POPS IN THE NORTH AND EAST DURING THE MORNING.
MAY SEE SOME FLURRIES IN THE AFTERNOON WITH STEEP LOW LEVEL LAPSE
RATES AND SOME LINGERING MOISTURE. SKIES SHOULD BECOME PARTLY
SUNNY IN THE AFTERNOON. COLD HIGHS IN THE UPPER 20S TO LOWER 30S
ARE EXPECTED.
ARCTIC COLD FRONT MOVES EAST THROUGH THE AREA BY EARLY SUNDAY
EVENING...WITH STRONG COLD AIR ADVECTION SUNDAY NIGHT INTO MONDAY
ACROSS THE AREA. THIS WILL BRING AN EVEN COLDER AIRMASS INTO THE
REGION.
925 MB TEMPERATURES SUGGEST HIGHS ONLY IN THE UPPER TEENS TO
LOWER 20S MONDAY...WITH LOWS SUNDAY NIGHT INTO THE TEENS AND
MONDAY NIGHT IN THE 8 TO 13 ABOVE ZERO RANGE. TIGHT PRESSURE
GRADIENT WITH DEEPENING LOW TO THE NORTH WILL BRING GUSTY WEST
WINDS...WHICH WILL BRING WIND CHILLS DOWN INTO THE SINGLE DIGITS
SUNDAY NIGHT...AND THE SINGLE DIGITS BELOW ZERO MONDAY NIGHT.
MODELS GENERALLY SHOWING A 500 MB LOW DEVELOPING OVER NORTHERN
MINNESOTA BY SUNDAY NIGHT...THEN MOVING EAST OVER LAKE SUPERIOR
ON MONDAY. A 500 MB VORTICITY MAXIMUM SHIFTS EAST THROUGH THE AREA
SUNDAY NIGHT...WITH MORE VORTICITY MAXIMA MOVING THROUGH ON
MONDAY. AREA FORECAST SOUNDINGS SHOW ENOUGH LOW LEVEL MOISTURE AND
STEEP LAPSE RATES WITHIN DENDRITE SNOW GROWTH ZONE TO MAINTAIN
POPS FOR SNOW SHOWERS SUNDAY NIGHT INTO MONDAY.
LONG TERM...TUESDAY THROUGH FRIDAY...FORECAST CONFIDENCE IS
MEDIUM.
GFS/ECMWF GENERALLY KEEP THE REGION WITHIN NORTHWEST FLOW AT 500
MB THROUGH THE REST OF THE WEEK. THIS SHOULD KEEP THE REGION COLD
DURING THIS TIME.
500 MB SHORTWAVE TROUGH SLIDES SOUTHEAST THROUGH THE AREA TUESDAY
NIGHT...WITH A TRAILING VORTICITY MAXIMUM CLIPPING OR SHIFTING
THROUGH THE REGION WEDNESDAY. MOISTURE IS MODEST DURING THIS
TIME...SO KEPT JUST LOW END POPS IN THE NORTH AND NORTHEAST DURING
THIS TIME.
MODELS THEN DIFFER MORE LATER IN THE WEEK WITH TRENDS...SO USED
CONSENSUS POPS AND TEMPERATURES FOR NOW.
AVIATION/12Z TAFS/...
VFR CONDITIONS UNTIL THE LIGHT SNOW STARTS FROM WEST TO EAST
ACROSS SRN WI DURING THE LATE AFTERNOON. CIGS TO FALL TO 1-2 KFT
WITH VSBYS OF 1-2 MILES WITH THE SNOW INTO THE EVENING HOURS. THE
HEAVIEST SNOW WILL END BY LATE EVENING BUT VERY LIGHT SNOW WILL
CONTINUE AT TIMES FROM THE LATE EVENING THROUGH THE OVERNIGHT.
VSBYS DURING THIS TIME WILL RANGE FROM 3-5SM BUT MAY RISE TO P6SM
BEFORE 12Z SUN. LOW STRATUS TO CONTINUE INTO SUN AM.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
UPDATE...DDV
TODAY/TONIGHT AND AVIATION...GEHRING
SUNDAY THROUGH FRIDAY...WOOD
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
433 AM MST SAT NOV 15 2014
.SHORT TERM...(TODAY THROUGH MONDAY NIGHT)
ISSUED AT 253 AM MST SAT NOV 15 2014
MAIN CONCERN IN THE NEAR TERM IS ACCUMULATING SNOW ACROSS SOUTHEAST
WY AND THE WESTERN NE PANHANDLE. WINTER WEATHER ADVISORIES LOOK GOOD
AND HAVE MADE NO CHANGES WITH THE MORNING FCST PACKAGE. HAVE SEEN A
RELATIVE LULL IN SNOW SHOWERS OVERNIGHT WITH SUBSIDENCE AND SOMEWHAT
DRY AIR ALOFT. HOWEVER...POTENT MIDLVL SHORTWAVE EVIDENT ON MORNING
WATER VAPOR LOOP OVER THE PAC NW WILL MOVE SOUTHEAST TODAY. COOLING
CLOUD TOPS OVER CENTRAL WY SUGGEST AN UPTICK IN PCPN COVERAGE OVER
THE NEXT FEW HOURS...SO WILL KEEP CATEGORICAL POPS GOING. LOOKING AT
TWO DISTINCT AREAS OF SNOW ACCUMULATIONS. FIRST ACROSS THE NORTHERN
TIER OF COUNTIES WITH FRONTOGENESIS ALONG THE SFC FRONT. SECOND
ALONG AND WEST OF THE LARAMIE RANGE WITHIN THE LEFT EXIT REGION OF A
105 KT H25 JET STREAK NOW ENTERING NORTHERN UT. BOTH AREAS COINCIDE
WELL WITH A MIDLVL MOISTURE PLUME OVERSPREADING THE CWA. A GENERAL 2
TO 5 INCH SNOWFALL SEEMS PROBABLE IN THESE CORRIDORS. EVEN IF WE DO
NOT SEE ADVISORY CRITERIA AMOUNTS...NORTHWEST WINDS WILL GUST IN
EXCESS OF 30 MPH TODAY WHICH WILL CREATE BLOWING/DRIFTING. WEBCAMS
ALREADY LOOK QUITE NASTY IN THE RAWLINS IN ELK MOUNTAIN AREAS AS OF
09Z THIS MORNING. THOUGHT ABOUT A TEMPORAL EXTENTION OF THE ADVISORY
THROUGH THE AFTN FOR BLOWING SNOW AFTER ACCUMULATIONS END...BUT WILL
LET THE DAY SHIFT MONITOR CONDITIONS TO SEE JUST HOW BAD VISIBILITY
BECOMES LATER ON.
SNOW HAS BEEN DIFFICULT TO COME BY IN THE CHEYENNE AREA SO FAR. IT
STILL LOOKS LIKE WE HAVE A WINDOW OF OPPORTUNITY IN THE 12-15Z TIME
FRAME AS THE NAM SHOWS A BAND OF MODERATE H7 FRONTOGENESIS FROM THE
SOUTHERN LARAMIE RANGE EAST INTO KIMBALL COUNTY NE. MAY BE ENOUGH
FOR A QUICK 1 TO 2 INCHES...BUT NOT MUCH MORE. WITH NORTHWEST WINDS
GUSTING 25 TO 35 MPH...DAY SHIFT MIGHT NEED TO CONSIDER A BLOWING
SNOW ADVISORY FOR CENTRAL AND EASTERN LARAMIE COUNTY. THE MOUNTAINS
STILL LOOK PRIME FOR 8 TO 12 INCHES OF TOTAL ACCUMULATION. NVA WILL
SPREAD ACROSS THE AREA BY LATE AFTN...SO EXPECT A GRADUAL DECREASE
IN PCPN COVERAGE FROM NORTHWEST TO SOUTHEAST THROUGH EARLY EVE. DRY
AFTER 00Z OUTSIDE OF A FEW FLURRIES. STRONG LLVL COLD AIR ADVECTION
WILL CONTINUE TODAY WITH THE FROPA...WITH GFS H7 TEMPS PLUNGING TO
THE -17C TO -20C RANGE BY 00Z SUN. SURFACE TEMPS WILL MOST LIKELY
HOLD STEADY TODAY OR EVEN FALL SLIGHTLY INTO THE AFTN. DRYING ALOFT
SIGNALS CLEARING INTO TONIGHT...AND WITH FRESH SNOWPACK COMES VERY
COLD TEMPERATURES TONIGHT. GUSTY WEST WINDS MIGHT KEEP THINGS MIXED
ENOUGH TO PREVENT TEMPERATURES FROM REALLY TANKING...BUT IT WILL BE
SUFFICIENT FOR DANGEROUS WIND CHILLS BETWEEN -20 AND -30F. EXPECT
WIND CHILL ADVISORIES WILL BE NECESSARY.
BOTH THE NAM AND GFS SUGGEST A FAIRLY POTENT SHORTWAVE DIVING SOUTH
ACROSS THE WESTERN DAKOTAS ON SUN AFTN. WHILE THIS DOES PROVIDE A
REINFORCING SHOT OF COLD AIR...THE GOOD CAA DOES NOT ARRIVE UNTIL
LATE. AS SUCH...EXPECT A PERIOD OF GUSTY WEST/DOWNSLOPE WINDS EAST
OF THE LARAMIE RANGE TO CONTRIBUTE TO COMPRESSIONAL WARMING THROUGH
EARLY AFTN. TRENDED HIGHER FOR MAX TEMPS BECAUSE OF THIS. MOISTENING
ALOFT AND STRONG PVA SUGGESTS LIGHT SNOW SHOWERS ACROSS OUR NORTHERN
AND EASTERN ZONES...SO ADDED LOW-END POPS THERE. COOLER FOR MON WITH
CYCLONIC FLOW ALOFT AND SURFACE HIGH PRESSURE ENCOMPASSING MUCH OF
THE CENTRAL AND NORTHERN ROCKIES.
.LONG TERM...(TUESDAY THROUGH FRIDAY)
ISSUED AT 253 AM MST SAT NOV 15 2014
LONG TERM LOOKS DRY FOR THE MOST PART WITH TEMPERATURES BACK TO
NEAR NORMAL FOR THIS TIME OF YEAR. WE STAY IN A NORTHWEST FLOW
THAT COULD BRING SOME QUICK HITTING SNOW SHOWERS MOSTLY TO THE
MOUNTAINS. THE MOST PROMINENT BEING THURSDAY. ECMWF ADVERTISING
THIS WITH THE GFS SOLUTION ON THE SHORTWAVE FURTHER NORTH AND EAST
OF OUR CWFA. DID KEEP SOME LOW CHANCE POPS IN THE FORECAST FOR THE
MOUNTAINS. MOST OTHER PLACES DRY THROUGH FRIDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 430 AM MST SAT NOV 15 2014
BASED 12Z TERMINAL FORECASTS OFF THE LATEST HRRR FORECAST.
CURRENT MOSAIC RADAR SHOWING SNOW SHOWERS INCREASING IN COVERAGE.
SEEING BAND OF MORE INTENSE SNOW JUST NORTH OF KCYS THIS MORNING
THAT IS MOVING SOUTH...SO KCYS SHOULD BE COMING DOWN HARD OVER THE
NEXT HOUR OR SO. MORNING HOURS THROUGH 18Z WILL SEE THE MOST
WIDESPREAD IFR/LIFR CONDITIONS ACROSS SOUTHEAST WYOMING AND
NEBRASKA PANHANDLE WITH IMPROVING CONDITIONS AFTERWARDS.
&&
.FIRE WEATHER...
ISSUED AT 253 AM MST SAT NOV 15 2014
NO FIRE WEATHER CONCERNS THROUGH THIS WEEKEND. ANOTHER ARCTIC SYSTEM
WILL BRING SNOW ACROSS MOST AREAS THROUGH SATURDAY. SEVERAL INCHES
OF SNOW WILL ACCUMULATE...ESPECIALLY IN THE HIGHER ELEVATIONS OF
SOUTHERN WYOMING. THIS SNOW WILL BE FOLLOWED BY BRISK SURFACE WIND
AND COLD TEMPERATURES SUNDAY INTO SUNDAY NIGHT.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER WEATHER ADVISORY UNTIL 11 AM MST THIS MORNING FOR
WYZ101>103-112-114.
WINTER WEATHER ADVISORY UNTIL 1 PM MST THIS AFTERNOON FOR
WYZ104>106-109>111-113-115>117.
NE...WINTER WEATHER ADVISORY UNTIL 11 AM MST THIS MORNING FOR NEZ002-
095.
&&
$$
SHORT TERM...CLH
LONG TERM...GCC
AVIATION...GCC
FIRE WEATHER...CLH
AREA FORECAST DISCUSSION
NWS PUEBLO CO
330 PM MST SAT NOV 15 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 330 PM MST SAT NOV 15 2014
...WIDESPREAD SNOW TO IMPACT THE REGION TONIGHT...
COLD FRONT HAS ALREADY DROPPED THROUGH SOUTHEAST COLORADO THOUGH
CORE OF COLDER AIR IS STILL SITTING ACROSS NORTHEAST COLORADO AND
NORTHERN EL PASO COUNTY WHERE TEMPERATURES ARE IN THE TEENS (VS. THE
UPPER 20S AND 30S ACROSS THE REMAINDER OF THE SOUTHEAST PLAINS).
MAIN UPPER TROF IS CURRENTLY ACROSS WY/ID AND WILL CONTINUE DROPPING
SOUTHWARD INTO THE 4 CORNERS REGION TONIGHT. UPPER JET ACROSS CO
HAS LED TO SOME BANDED SNOW ACROSS NORTHEAST COLORADO...WITH SOME
PERIODIC LIGHT SNOW CONTINUING ACROSS THE NORTHERN PORTIONS OF
MONUMENT HILL WHERE MOST OF THE FORCING IS LIKELY DUE TO SHALLOW
OROGRAPHICS. SNOW ALSO CONTINUES ALONG THE CONTINENTAL
DIVIDE...THOUGH INTENSITIES HAVE LET UP QUITE A BIT FROM THIS
MORNING. THAT WILL BE CHANGING IN THE NEXT 6 HOURS THOUGH AS
DYNAMICS FROM THE UPPER TROF SHIFTS SOUTHWARD WITH TIME. BEST QG
FORCING APPEARS TO DROP THROUGH THE WESTERN AND SOUTHERN PORTIONS OF
THE FORECAST AREA. CHALLENGES STILL REVOLVE AROUND SNOW AMOUNTS.
MODELS APPEAR TO BE STRUGGLING THE MOST ACROSS THE PIKES PEAK
REGION...WITH GFS PREDICTING A HEALTHY 3-7 INCHES ACROSS THIS
REGION...WHILE NAM12 HAS MORE IN THE 1 TO 3 INCH RANGE. RAP IS
GOING ALONG WITH GFS...WHILE ECMWF AND OTHER HIGH RES MODELS
(ARW..NMM) AGREE MORE WITH THE NAM. SO HAVE TO HUNT FOR CLUES TO
SUGGEST WHERE TO PUT THE NORTHERN EDGE OF THE HEADLINE AREAS. GIVEN
THE TRACK OF THE UPPER FORCING IS FARTHER TO THE SOUTH...AND THE
BEST UPGLIDE OVER THE H7 FRONT SEEMS TO BE MORE ACROSS SOUTHERN
AREAS...HAVE LEFT PIKES PEAK AND EL PASO COUNTY OUT OF THE ADVISORY
AREA FOR NOW. SNOWFALL GRIDS WILL CARRY AROUND 2-5 INCHES WITH
SOUTHERN EL PASO COUNTY MORE IN THE 2 TO 3 INCH RANGE.
WHERE MODELS AGREE BETTER IS ACROSS THE SOUTHEAST MOUNTAINS AND
SOUTHERN I-25 CORRIDOR. HAVE EXPANDED THE ADVISORIES NORTHWARD AND
EASTWARD A TAD. PUEBLO COUNTY IS ALWAYS A CHALLENGE AS HEAVIER
AMOUNTS MAY END UP ACROSS SOUTHERN AND WESTERN PORTIONS OF THE
COUNTY WHILE NORTHEAST PORTIONS SEE MORE IN THE 1-3 INCH RANGE. ALL
THE MODELS SEEM TO HIT THE SOUTHERN SANGRES WITH THE HEAVIEST
AMOUNTS OF QPF...AND THIS LOOKS REASONABLE GIVEN THE TRACK OF THE
SYSTEM. THUS HAVE UPGRADED THE WINTER WEATHER ADVISORY TO A WARNING
FOR THE SOUTHERN SANGRES. HAVE ALSO ADDED EASTERN LAS ANIMAS COUNTY
TO THE ADVISORY WHERE THE NORTHERN SLOPES OF THE RATON WILL HAVE THE
BENEFIT OF SOME NORTHEAST OROGRAPHICS.
WILL HOLD ON TO THE WINTER STORM WARNINGS ALONG THE CONTINENTAL
DIVIDE. THESE AREAS SHOULD PICK UP ANOTHER 5 TO 10 INCHES OVERNIGHT
WITH THE HEAVIEST ACROSS SOUTHERN PORTIONS OF THE EASTERN SAN JUAN
MOUNTAINS.
A COUPLE OTHER CHALLENGING SPOTS INCLUDE THE SAN LUIS VALLEY WHERE
HIGH RES MODELS ARE NOT SHOWING MUCH SNOW. HAVE GONE WITH AROUND AN
INCH TO 1.5 ACROSS THE VALLEY FLOOR GIVEN THIS AREA WILL BE IN
BETTER PROXIMITY TO THE UPPER DYNAMICS. BEST CHANCE WILL COME IN
AFTER 10 PM FOR THIS AREA. BACA COUNTY IS THE FINAL CHALLENGE.
MODEL RUNS WERE SUGGESTING AROUND 2 TO 4 INCHES OUT THAT WAY...JUST
SHY OF ADVISORY CRITERIA...BUT LATEST NAM12 HAS COME IN HEAVIER...SO
THIS AREA MAY HAVE TO BE MONITORED CLOSELY IF THE HEAVIER SNOW BAND
SETS UP ACROSS THAT AREA.
HIGHLIGHTS WILL PARE OFF FROM NORTH TO SOUTH TOWARDS MORNING. MOST
OF THE SNOW WILL BE DONE BY 10Z UP NORTH...AND BY 13-16Z DOWN SOUTH.
MOSTLY SUNNY SKIES WILL RETURN BY MID DAY SUNDAY. TEMPERATURES
TONIGHT WILL DROP BACK DOWN INTO THE SINGLE DIGITS FOR MOST OF THE
SOUTHEAST PLAINS WHERE THE CORE OF THE COLDER AIR WILL SPREAD IN.
SOME SPOTS COULD DROP INTO THE NEGATIVE DIGITS UP NORTH IF CLEARING
CAN OCCUR EARLY ENOUGH. SAN LUIS VALLEY WILL HAVE THE BENEFIT OF
CLOUDS AND PRECIPITATION OVERNIGHT SO LOWS THERE MAY ONLY DROP INTO
THE TEENS. KEPT HIGH TEMPERATURES ON SUNDAY CLOSER TO THE COLDER
SIDE OF GUIDANCE. -KT
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 330 PM MST SAT NOV 15 2014
...A SLOW WARMING TREND...
A SLOW WARMING TREND TO AROUND MID NOVEMBER AVERAGES REMAINS IN THE
OFFING INTO THE MIDDLE OF THE UPCOMING WORK WEEK...AS COLD NORTH TO
NORTHWEST FLOW ALOFT ACROSS THE REGION SUNDAY NIGHT GIVES WAY TO
WARMER MORE WESTERLY FLOW BY WEDNESDAY. TEMPERATURES TO BE THE MAIN
CONCERN AND HEADACHE IN THE SHORT TERM...WITH HIGHS AND LOWS TO BE
INFLUENCED BY SNOW COVER. AT ANY RATE...HAVE GONE AT OR BELOW THE
COLDER SIDE OF GUIDANCE FOR SUNDAY NIGHT AND MONDAY...ESPECIALLY
ACROSS THE SOUTHEASTERN MTS AND PLAINS WITH LOWS IN THE SINGLE
DIGITS ABOVE AND BELOW ZERO AND HIGHS MAINLY IN THE 20S. INDUCED LEE
TROUGHING AHEAD OF A SHORT WAVE TRANSLATING ACROSS THE NORTHERN
ROCKIES SHOULD KEEP LOWS SLIGHTLY WARMER ACROSS THE EASTERN SLOPES
MONDAY NIGHT AND COULD BOOST HIGHS INTO THE 30S TO LOWER 40S
ACROSS THE LOWER ELEVATIONS ON TUESDAY.
BUILDING UPPER RIDGE ACROSS THE GREAT BASIN TUESDAY NIGHT FLATTENS
ACROSS THE STATE THROUGH WEDNESDAY NIGHT AS MINOR WAVES TRANSLATE
EAST ACROSS THE GREAT BASIN AND ROCKIES...WITH THE DOWNSLOPE FLOW
OWNING TO THE EXPECTED WARMING TEMPERATURES AND BRINGING CHANCES
OF LIGHT SNOWFALL TO THE HIGHER TERRAIN...MAINLY ALONG AND WEST OF
THE CONTDVD THURSDAY AND FRIDAY. LATEST MODELS ARE SHOWING A
STRONGER SYSTEM MOVING ACROSS THE GREAT BASIN FRIDAY AND ACROSS
THE ROCKIES ON SATURDAY...THOUGH BOTH THE GFS AND EC HAVE SHOWN
RUN TO RUN INCONSISTENCIES ON ITS TIMING AND STRENGTH. FOR
NOW...HAVE KEPT ANY PRECIPITATION CHANCES CONFINED TO THE HIGHER
TERRAIN FRIDAY NIGHT AND SATURDAY WITH TEMPERATURES AROUND
SEASONAL AVERAGES.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 330 PM MST SAT NOV 15 2014
EXPECT DETERIORATING CONDITIONS THROUGH THE EVENING WITH
CIGS DROPPING INTO THE IFR CATEGORY AT KCOS AND KPUB BY 00Z AS SNOW
DEVELOPS AND SPREAD OFF THE MOUNTAINS. BOTH TERMINALS COULD SEE
AROUND 2 TO 2.5 INCHES OF SNOW. SNOW SHOULD DIMINISH AFTER 10Z FOR
BOTH TERMINALS WITH CIGS BREAKING BY 15Z. VFR CONDITIONS WILL
CONTINUE THROUGH SUNDAY. KALS WILL SEE A LITTLE LATER START TO THE
SNOW...WITH SNOW SPREADING IN AFTER 05Z...AND CONTINUING THROUGH
12Z. CIGS MAY DROP INTO THE IFR CATEGORY AT TIMES OVERNIGHT.
WIDESPREAD MTN OBSCURATIONS CAN BE EXPECTED TONIGHT WHICH WILL
DECREASE FROM NORTH TO SOUTH SUNDAY MORNING.
MEANWHILE...GUSTY NORTH WINDS WILL CONTINUE THROUGH THE EVENING
ACROSS THE PLAINS BEFORE DIMINISHING OVERNIGHT. KALS WILL SEE GUSTY
WEST WINDS...SHIFTING AROUND TO THE NORTH AFTER 08-09Z AS THE SYSTEM
MOVES ACROSS. WINDS ON SUNDAY WILL BE LIGHTER AT ALL THREE TAF
SITES. -KT
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 9 AM MST SUNDAY FOR COZ072-073-079-
080-087-088-094.
WINTER WEATHER ADVISORY UNTIL 5 AM MST SUNDAY FOR COZ077-078-083-
086.
WINTER STORM WARNING UNTIL 5 AM MST SUNDAY FOR COZ058-060-066.
WINTER STORM WARNING UNTIL 9 AM MST SUNDAY FOR COZ074-075.
WINTER STORM WARNING UNTIL 9 AM MST SUNDAY FOR COZ068.
&&
$$
SHORT TERM...KT
LONG TERM...MW
AVIATION...KT
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1050 AM MST SAT NOV 15 2014
.UPDATE...
ISSUED AT 1003 AM MST SAT NOV 15 2014
BASED ON LATEST SAT AND MSAS SFC PRESSURE RISES...FRONT ALREADY
PUSHING THROUGH EL PASO COUNTY. IRONICALLY THE MIXING HAS BROUGHT
SOME WARMING WITH LOCATIONS FINALLY HITTING ABOVE FREEZING THE
FREEZING MARK...BUT TEMPERATURES ARE IN THE TEENS BEHIND THE
FRONT SO EXPECT ANOTHER QUICK DROP IN TEMPERATURES THROUGH THE
AFTERNOON ACROSS SE CO. HIGHS HAVE ALREADY LIKELY BEEN REACHED IN
EL PASO COUNTY WITH FALLING TEMPERATURES EXPECTED THROUGH THE
REMAINDER OF THE DAY. MODELS CONTINUING TO STRUGGLE WITH TIMING OF
PRECIPITATION AS IT IS ALREADY SNOWING UP IN NE COLORADO WHICH
MODELS ARE NOT HANDLING WELL. SPED UP THE TIMING OF SNOW IN THE
GRIDS. EXPECT LIGHT SNOW TO START BY LATE MORNING ACROSS MONUMENT
HILL...WITH HEAVIER SNOW HOLDING OFF UNTIL 22Z ACROSS NORTHERN
PORTIONS OF THE AREA...THEN RAPIDLY SPREADING SOUTHWARD THROUGH
00Z AS FORCING FROM THE UPPER TROF APPROACHES. -KT
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 412 AM MST SAT NOV 15 2014
...MORE SNOW AND ARCTIC AIR ON THE WAY...
CURRENTLY...
THE LEADING EDGE OF THE NEXT ARCTIC INTRUSION WAS ALONG THE CO/WY
BORDER AND IT WAS HEADING SOUTH. CLOSER TO HOME...TEMPERATURES AT 3
AM VARIED CONSIDERABLY ACROSS THE PLAINS...AS ELEVATIONS GENERALLY
ABOVE 6000 FEET WERE IN THE RELATIVELY WARMER AIR (30S AND 40S)
WHILE AREAS BELOW 6000 WERE IN THE TEENS AND 20S. IN THE MTNS AND
VALLEYS...IT WAS RELATIVELY WARM WITH TEMPS IN THE 20S AND 30S.
RADAR...OBS AND WEB CAMS INDICATED THAT SNOW STILL OCCURRING OVER
THE CONTDVD.
TODAY...
WEATHER WILL BE QUITE ACTIVE DURING THE NEXT 24. HRRR INDICATES THAT
THE LEADING EDGE OF THE ARCTIC AIR WILL MOVE INTO EL PASO COUNTY
AROUND 9-10 AM AND WILL PROGRESS SOUTH...REACHING THE NEW MEXICO
BORDER BY 3 PM. LIKEWISE...MAX TEMPS TODAY WILL LIKELY OCCUR THIS
MORNING ACROSS THE PIKES PEAK REGION AND MIDDAY ACROSS THE REST OF
THE REGION. TEMPS WILL QUICKLY FALL AFTER THE ARCTIC FRONT GOES BY.
AS FOR PRECIP...IN THE MTNS...STEADY SNOW...SOME HEAVY...WILL
CONTINUE ACROSS THE CENTRAL MTNS ALL DAY TODAY. SNOW ACROSS THE SAN
JUANS WILL DECREASE LATER THIS MORNING BUT WILL RAMP UP ONCE AGAIN
BY MID AFTERNOON.
PRECIP ON THE PLAINS WILL GENERALLY DEVELOP ACROSS THE PIKES PEAK
REGION SHORTLY AFTER NOON AND WILL PICK UP AS THE AFTERNOON
PROGRESSES. STEADY SNOW WILL LIKELY BE ONGOING BY LATE AFTERNOON
ACROSS EL PASO COUNTY AND TRAVEL WILL ONCE AGAIN BECOME DIFFICULT
ACROSS THIS REGION. WINDS WILL LIKELY BE A BIT GUSTY SO AREAS OF
BLOWING SNOW WILL OCCUR.
BY LATE AFTERNOON THE SNOW WILL DEVELOP FARTHER SOUTH DOWN THE I-25
CORRIDOR AND EASTERN MTN REGION. OTHERWISE...THE REST OF THE PLAINS
WILL LIKELY REMAIN DRY.
TONIGHT...
MAIN CONCERN DURING THIS PERIOD IS THE SPANISH PEAKS/RATON MESA/WET
MTNS REGION AS ALL GUIDANCE IS SHOWING PRETTY HEALTHY QPF BULLSEYES
OVER THIS REGION. FOR NOW I HAVE ISSUED A WINTER WEATHER ADVISORY
FOR THIS REGION WITH THE AREA LIKELY RECEIVING 3-6 INCHES OF SNOW AT
THE LOWER ELEVATIONS OF LAS ANIMAS AND HUERFANO COUNTIES WHILE HIGHER
ELEVATIONS WILL LIKELY RECEIVE 4 TO 10 INCHES OF SNOW. IT IS
POSSIBLE THAT THESE VALUES MAY BE ON THE LOW SIDE...ESPECIALLY IF
GUIDANCE DOES VERIFY. WILL ALLOW LATER SHIFT TO REANALYZE AND
UPGRADE TO WARNING STATUS IF LATER SIMULATIONS SHOW LARGE QPF VALUES
OVER AFOREMENTIONED REGION.
FOR THE REST OF THE PLAINS...EL PASO COUNTY SHOULD GENERALLY RECEIVE
ABOUT 2-4" OF SNOW WITH THIS EVENT WITH 2-6 IN TELLER COUNTY AND
PIKES PEAK. PUEBLO/FREMONT COUNTIES WILL LIKELY RECEIVE ANYWHERE
FROM BETWEEN 2 AND 5 INCHES. OVER THE FAR EAST PLAINS...1 TO 2
INCHES WILL BE POSSIBLE.
THE MOUNTAINS WILL CONTINUE TO SEE SNOW...HOWEVER THE SNOW WILL END
FROM S TO N ACROSS THE C MTNS LATER TONIGHT. OVERALL ANOTHER 6 TO
12 INCHES OF SNOW IS LIKELY OVER THE CONTDVD REGION
TEMPS TONIGHT WILL BE COLD ONCE AGAIN ACROSS THE ENTIRE REGION.
SINGLE DIGITS WILL OCCUR ACROSS NEARLY ALL OF THE REGION EXCEPT
TEENS MAINLY IN THE SAN LUIS VALLEY. /HODANISH
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 412 AM MST SAT NOV 15 2014
...COLD SUNDAY THEN GRADUAL WARMING...
SNOW WILL LINGER ALONG THE SOUTHERN BORDER AREAS EARLY
SUNDAY...BUT SHOULD MOSTLY END BY NOON AS PROGRESSIVE
SHORTWAVE MOVES ON THROUGH. NEW SHOT OF ARCTIC AIR WILL
BRING ONE MORE REALLY COLD DAY SUNDAY BUT THEN THINGS WILL
START TO WARM UP AND DRY OUT FOR MOST OF THE UPCOMING WEEK.
THE WARM UP MAY START A LITTLE SLOW ON MONDAY AS SNOW COVER AND
LIGHT PRESSURE GRADIENTS WILL TEND TO KEEP SURFACE INVERSIONS IN
PLACE THROUGH THE DAY. BY TUESDAY...IT LOOKS LIKE WE SHOULD SEE A
LITTLE BETTER MIXING AS DOWNSLOPE PRESSURE GRADIENTS DEVELOP. THIS
SHOULD HELP BRING CHINOOK BREEZES OFF THE MOUNTAINS TO START
WARMING THE AIR.
COULD BE A LITTLE SET BACK WEDNESDAY AS THE MODELS ARE SHOWING A
WEAK SURFACE HIGH DROPPING THROUGH THE PLAINS THIS DAY. THIS COULD
REESTABLISH INVERSIONS IF THERE IS ENOUGH COOLING WITH THE HIGH
AND IF THERE IS ANY SNOW COVER REMAINING.
THURSDAY AND ESPECIALLY FRIDAY...IT LOOKS LIKE SOME WEAK ENERGY
FROM THE PACIFIC WILL START MOVING BACK INTO THE REGION. THIS
ENERGY COULD SPREAD SOME SNOW SHOWERS INTO THE CONTINENTAL DIVIDE
THURSDAY...AND EAST TO THE REST OF THE MOUNTAINS AND PIKES PEAK
REGION ON FRIDAY. THE APPROACHING ENERGY DOESN`T LOOK STRONG AT
THIS POINT SO FORECAST CONFIDENCE IS LOW AT THIS TIME. TEMPERATURES
WILL LIKELY REMAIN MILD THURSDAY...BUT THEN START TO COOL ON
FRIDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1016 AM MST SAT NOV 15 2014
FRONT ALREADY MOVING INTO NORTHERN PUEBLO COUNTY AS OF 1745Z.
EXPECT IT TO HIT THE KPUB TAF SITE WITHIN THE NEXT HOUR. WINDS
BEHIND THE FRONT WILL BE FROM THE NORTHEAST AT 15-30 KTS THROUGH
THE AFTERNOON. IFR STRATUS IS ALREADY BANKED UP ACROSS NORTHERN EL
PASO COUNTY...AND EXPECTED TO SPREAD SOUTHWARD AND FILL IN
AGAINST THE MOUNTAINS THROUGH THE AFTERNOON. TIMING OF SNOWFALL
IS A CHALLENGE AS FORECAST MODELS NOT HANDLING IT WELL WHERE SNOW
IS ALREADY FALLING ACROSS NORTHEAST CO. EXPECT SOME LIGHT SNOW TO
BEGIN IN KCOS AROUND 22Z...AND IN KPUB BY 23Z. HEAVIER SNOW WILL
COME IN AFTER 00Z AS A BAND DEVELOPS WITH THE INCOMING SYSTEM AND
SPREADS SOUTHWARD. IFR TO LIFR CONDITIONS CAN BE EXPECTED
OVERNIGHT. KALS WILL SEE A LATER START TO SNOW...PROBABLY AROUND
05Z...BUT SHOULD SEE IFR CONDITIONS DEVELOP OVERNIGHT WITH SNOW.
ALL THREE TERMINALS SHOULD EXPECT A COUPLE INCHES...WITH HEAVIER
AMOUNTS NEAR THE MOUNTAINS. RAPIDLY IMPROVING CONDITIONS WILL SET
IN EARLY SUNDAY MORNING WITH ANY LINGERING VFR STRATUS CLEARED
OUT BY 15Z. -KT
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 5 PM THIS AFTERNOON TO 9 AM MST
SUNDAY FOR COZ072>075-079-080-087-088.
WINTER STORM WARNING UNTIL 5 AM MST SUNDAY FOR COZ058-060-066-
068.
&&
$$
UPDATE...KT
SHORT TERM...HODANISH
LONG TERM...LW
AVIATION...KT
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1015 AM MST SAT NOV 15 2014
.UPDATE...
ISSUED AT 954 AM MST SAT NOV 15 2014
RADAR SHOWS SNOW BANDS INCREASING WHILE CLOUD TOPS ARE ALSO
COOLING ACROSS THE REGION. AIRMASS IS POTENTIALLY UNSTABLE PER 12Z
GRAND JUNCTION SOUNDING AND NOSE OF FIRST UPPER LEVEL SPEED MAX IS
AIDING UPPER LEVEL DIVERGENCE. CONVECTIVE SHOWERS EVIDENCED ON THE
WESTERN SLOPE RADAR WHILE BANDS OF HEAVIER SNOW HAVE ALREADY MOVED
ACROSS THE NORTHERN PLAINS INCLUDING FORT COLLINS WHICH PICKED UP
A QUICK ONE HALF TO ONE INCH OF SNOW WHEN A BAND MOVED ACROSS.
FIRST SPEED MAX WILL PASS OFF TO THE NORTH LATER THIS MORNING
WHILE NEXT JET MAX WILL PLOW INTO WESTERN COLORADO LATE THIS
AFTERNOON/EVENING. LIFT ASSOCIATED WITH THIS NEXT SURGE SHOULD
BRING ANOTHER INCREASE IN SNOW MAINLY ALONG AND SOUTH OF THE I-70
CORRIDOR. AS A RESULT...WILL UPGRADE THE ADVISORY IN THE I-70
CORRIDOR OF THE MOUNTAINS INCLUDING SUMMIT COUNTY...ZONE 34...TO
A WINTER STORM WARNING THROUGH MIDNIGHT. OTHER MAIN CHANGES WERE
TO INCREASE POPS AND SNOW AMOUNTS ON THE PLAINS PER LATEST
TRENDS...AND ALSO DELAY ENDING OF SNOW MAINLY FROM DENVER AND
LIMON SOUTHWARD THIS EVENING AS NEXT BATCH OF LIFT SEEN IN THE Q-G
FIELDS PROVIDE AT LEAST WEAK UPPER LEVEL LIFT. TEMPERATURE
FORECAST ON TRACK WITH FALLING TEMPS IN ARCTIC AIRMASS THROUGH THE
REST OF THE DAY AND BELOW ZERO READINGS MUCH OF THE PLAINS
TONIGHT.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT )
ISSUED AT 450 AM MST SAT NOV 15 2014
TWO WEATHER FEATURES TO CONTEND WITH THIS MORNING. FIRST IS THE
ARCTIC FRONT SLIPPING SOUTH THROUGH WELD AND WASHINGTON COUNTIES
AT THE MOMENT. A PRE-FRONTAL WIND SHIFT HAS ALREADY SWEPT THROUGH
THE DENVER METRO AREA...BUT THE COLDER AIR AND LOWER CLOUDS ARE
OBSERVED NORTH OF THE MAIN FRONTAL BNDRY. AT PRESENT SPEED COULD
SEE THE FRONT INTO THE GREATER DENVER METRO AREA WITH THE NEXT30
MINS OR SO. PRESSURE RISES BEHIND THIS FRONT NOTHING LIKE THOSE
PRESENT BEHIND THE STRONGER ARCTIC FRONT LAST MONDAY.
NEVERTHELESS...SHOULD SEE TEMPERATURES SLIPPING ON THE PLAINS
THROUGH THE MORNING WITH GUSTY N-NELY. GOOD BET TEMPERATURES HAVE
ALREADY MAXED OUT FOR TODAY ON THE PLAINS. GUIDANCE INDICATING
SINGLE DIGIT TEMPERATURES BY THIS AFTERNOON.
FURTHERMORE...SNOWFALL EAST OFF THE MTNS IS STILL UP IN
WYOMING...BUT WITHIN NEXT FEW HOURS SHOULD SEE A BAND OF LIGHT
SNOW MAKING ITS WAY SOUTHWARD ACRS THE CWA ACCORDING TO THE HRRR
AND RAP. ACCUMULATION RATES SHOULD REMAIN ON THE LIGHT
SIDE...GENERALLY UNDER A QUARTER INCH PER HOUR THROUGH MIDDAY.
HOWEVER MODELS SHOW A BAND OF HEAVIER SNOW DEVELOPING ALONG THE
I-70 CORRIDOR DURING THE MID TO LATE AFTERNOON HOURS WITH SNOWFALL
RATES AROUND 1/2 TO 3/4 INCH PER HOUR. SHOULD SEE PRECIP COMING
TO AN END FROM NORTH TO SOUTH DURING THE EVENING HOURS AS LIFT AND
INSTABILITY SHIFT SOUTH OF THE AREA.
IN THE HIGH COUNTRY...AN INFLUX OF PACIFIC MOISTURE ON THE NOSE OF
A 110+ KT JET WILL RESULT IN A STEADY INFLUX OF SNOWFALL ACROSS
THE HIGH COUNTRY THROUGH THE MORNING. WEST FACING ASPECTS IN BEST
POSITION TO PICK UP GREATEST SNOW AMOUNTS OVER THE NEXT 18 HOURS.
WINTER WEATHER ADVISORY FOR SNOW AND BLOWING SNOW NOW IN EFFECT
FOR MTN ZONES. MTN VALLEYS ZONES 30 AND 32 HAVE BEEN ADDED TO THE
ADVSY. 5-12 INCH ACCUMS EXPECTED IN MTN ZONES...WITH 3-7 INCH
TOTALS ON THE VALLEY FLOORS. INCREASING WEST WINDS WITH ARRIVAL
OF THE JET LATER THIS MORNING WILL LIKELY PRODUCE BLOWING AND
DRIFTING SNOW IN OPEN AREAS IN THE HIGH COUNTRY MAKING TRAVEL
DIFFICULT IF NOT HAZARDOUS FOR A TIME THIS AFTERNOON.
JET...MOISTURE AND DYNAMICS ARE FORECAST TO MIGRATE SOUTH AND EAST
OF THE AREA THIS EVENING PUTTING A GRADUAL END TO SNOWFALL AND
WINDS STARTING IN THE NORTHERN AREAS. CLEARING SKIES LATE TONIGHT
WILL RESULT IN BITTER OVERNIGHT LOWS AND POSSIBLY SOME DENSE FOG
ON THE PLAINS BEFORE MORNING.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 450 AM MST SAT NOV 15 2014
THE UPPER LEVEL TROF AXIS WILL SAG SOUTHWARD OVER SOUTHERN
COLORADO SUNDAY MORNING WITH DRYING AIRMASS. HOWEVER WILL STILL
HAVE RATHER COLD TEMPERATURES DURING THE DAY SUNDAY WITH FRESH
SNOW COVER AND LINGERING LOW LEVEL INVERSIONS. BY SUNDAY
AFTERNOON AND EVENING AN UPPER LEVEL TROF SWEEPS ACROSS THE
NORTHERN HIGH PLAINS WITH SOME REFLECTION AT THE SURFACE OVER FAR
NORTHEAST COLORADO. STILL REMAINS A SUBSIDENT AIRMASS BUT A MID
LEVEL DECK OF CLOUDS EXPECTED. WILL KEEP CONDITIONS DRY FOR NOW
BUT GUSTY NORTHWEST WINDS OVER THE PLAINS.
MUCH OF NEXT WEEK THROUGH WEDNESDAY WILL BE CHARACTERIZED WITH A
STRONG NORTHWEST FLOW PATTERN WITH HIGH AMPLITUDE RIDGING ALONG
WEST COAST AND STRONG LOW OVER GREAT LAKES REGION. THERE WILL BE A
SLOW MODERATION OF TEMPERATURES WHILE GUSTY WINDS CONTINUE AT
TIMES OVER THE HIGH MOUNTAINS. COULD SEE SOME GUSTS UP TO 50 MPH
OVER THE MOUNTAIN PASSES.
BY THURSDAY AND FRIDAY...SOME PACIFIC MOISTURE BEGINS TO STREAM
INTO THE MOUNTAINS WITH A WEAK DISTURBANCE. WILL HAVE LOW POPS IN
FOR NOW. FOR LOWER ELEVATIONS...GENERALLY MILD WITH READINGS IN
THE 40S ALONG WITH DRY CONDITIONS.
&&
.AVIATION...(FOR THE TAFS THROUGH 18Z SUNDAY MORNING)
ISSUED AT 954 AM MST SAT NOV 15 2014
LIGHT SNOW AND IFR/MVFR CEILINGS/VSBYS OVER HAVE OVERSPREAD THE
FRONT RANGE AIRPORTS THIS MORNING. THESE CONDITIONS WILL CONTINUE
THROUGH THE AFTERNOON HOURS ALTHOUGH A COUPLE HEAVIER SNOW BANDS
COULD DROP VSBYS TO 1/4-1/2SM FOR A 30-45 MINUTE PERIOD. MAIN
CHANGE WAS TO DELAY THE ENDING OF SNOW AS NEXT UPPER LEVEL
DISTURBANCE COULD VERY WELL KEEP SNOW IN THE FORECAST TIL AROUND
06Z/07Z. LATEST SHORT RANGE RAP AND HRRR ALSO POINT TO THIS. TOTAL
SNOW ACCUMULATIONS 1-3 INCHES EXPECTED.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 8 PM MST THIS EVENING FOR
COZ030>033.
WINTER STORM WARNING UNTIL MIDNIGHT MST TONIGHT FOR COZ034.
&&
$$
UPDATE...BARJENBRUCH
SHORT TERM...BAKER
LONG TERM...ENTREKIN
AVIATION...BARJENBRUCH
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1013 AM MST SAT NOV 15 2014
.UPDATE...
ISSUED AT 1003 AM MST SAT NOV 15 2014
BASED ON LATEST SAT AND MSAS SFC PRESSURE RISES...FRONT ALREADY
PUSHING THROUGH EL PASO COUNTY. IRONICALLY THE MIXING HAS BROUGHT
SOME WARMING WITH LOCATIONS FINALLY HITTING ABOVE FREEZING THE
FREEZING MARK...BUT TEMPERATURES ARE IN THE TEENS BEHIND THE
FRONT SO EXPECT ANOTHER QUICK DROP IN TEMPERATURES THROUGH THE
AFTERNOON ACROSS SE CO. HIGHS HAVE ALREADY LIKELY BEEN REACHED IN
EL PASO COUNTY WITH FALLING TEMPERATURES EXPECTED THROUGH THE
REMAINDER OF THE DAY. MODELS CONTINUING TO STRUGGLE WITH TIMING OF
PRECIPITATION AS IT IS ALREADY SNOWING UP IN NE COLORADO WHICH
MODELS ARE NOT HANDLING WELL. SPED UP THE TIMING OF SNOW IN THE
GRIDS. EXPECT LIGHT SNOW TO START BY LATE MORNING ACROSS MONUMENT
HILL...WITH HEAVIER SNOW HOLDING OFF UNTIL 22Z ACROSS NORTHERN
PORTIONS OF THE AREA...THEN RAPIDLY SPREADING SOUTHWARD THROUGH
00Z AS FORCING FROM THE UPPER TROF APPROACHES. -KT
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 412 AM MST SAT NOV 15 2014
...MORE SNOW AND ARCTIC AIR ON THE WAY...
CURRENTLY...
THE LEADING EDGE OF THE NEXT ARCTIC INTRUSION WAS ALONG THE CO/WY
BORDER AND IT WAS HEADING SOUTH. CLOSER TO HOME...TEMPERATURES AT 3
AM VARIED CONSIDERABLY ACROSS THE PLAINS...AS ELEVATIONS GENERALLY
ABOVE 6000 FEET WERE IN THE RELATIVELY WARMER AIR (30S AND 40S)
WHILE AREAS BELOW 6000 WERE IN THE TEENS AND 20S. IN THE MTNS AND
VALLEYS...IT WAS RELATIVELY WARM WITH TEMPS IN THE 20S AND 30S.
RADAR...OBS AND WEB CAMS INDICATED THAT SNOW STILL OCCURRING OVER
THE CONTDVD.
TODAY...
WEATHER WILL BE QUITE ACTIVE DURING THE NEXT 24. HRRR INDICATES THAT
THE LEADING EDGE OF THE ARCTIC AIR WILL MOVE INTO EL PASO COUNTY
AROUND 9-10 AM AND WILL PROGRESS SOUTH...REACHING THE NEW MEXICO
BORDER BY 3 PM. LIKEWISE...MAX TEMPS TODAY WILL LIKELY OCCUR THIS
MORNING ACROSS THE PIKES PEAK REGION AND MIDDAY ACROSS THE REST OF
THE REGION. TEMPS WILL QUICKLY FALL AFTER THE ARCTIC FRONT GOES BY.
AS FOR PRECIP...IN THE MTNS...STEADY SNOW...SOME HEAVY...WILL
CONTINUE ACROSS THE CENTRAL MTNS ALL DAY TODAY. SNOW ACROSS THE SAN
JUANS WILL DECREASE LATER THIS MORNING BUT WILL RAMP UP ONCE AGAIN
BY MID AFTERNOON.
PRECIP ON THE PLAINS WILL GENERALLY DEVELOP ACROSS THE PIKES PEAK
REGION SHORTLY AFTER NOON AND WILL PICK UP AS THE AFTERNOON
PROGRESSES. STEADY SNOW WILL LIKELY BE ONGOING BY LATE AFTERNOON
ACROSS EL PASO COUNTY AND TRAVEL WILL ONCE AGAIN BECOME DIFFICULT
ACROSS THIS REGION. WINDS WILL LIKELY BE A BIT GUSTY SO AREAS OF
BLOWING SNOW WILL OCCUR.
BY LATE AFTERNOON THE SNOW WILL DEVELOP FARTHER SOUTH DOWN THE I-25
CORRIDOR AND EASTERN MTN REGION. OTHERWISE...THE REST OF THE PLAINS
WILL LIKELY REMAIN DRY.
TONIGHT...
MAIN CONCERN DURING THIS PERIOD IS THE SPANISH PEAKS/RATON MESA/WET
MTNS REGION AS ALL GUIDANCE IS SHOWING PRETTY HEALTHY QPF BULLSEYES
OVER THIS REGION. FOR NOW I HAVE ISSUED A WINTER WEATHER ADVISORY
FOR THIS REGION WITH THE AREA LIKELY RECEIVING 3-6 INCHES OF SNOW AT
THE LOWER ELEVATIONS OF LAS ANIMAS AND HUERFANO COUNTIES WHILE HIGHER
ELEVATIONS WILL LIKELY RECEIVE 4 TO 10 INCHES OF SNOW. IT IS
POSSIBLE THAT THESE VALUES MAY BE ON THE LOW SIDE...ESPECIALLY IF
GUIDANCE DOES VERIFY. WILL ALLOW LATER SHIFT TO REANALYZE AND
UPGRADE TO WARNING STATUS IF LATER SIMULATIONS SHOW LARGE QPF VALUES
OVER AFOREMENTIONED REGION.
FOR THE REST OF THE PLAINS...EL PASO COUNTY SHOULD GENERALLY RECEIVE
ABOUT 2-4" OF SNOW WITH THIS EVENT WITH 2-6 IN TELLER COUNTY AND
PIKES PEAK. PUEBLO/FREMONT COUNTIES WILL LIKELY RECEIVE ANYWHERE
FROM BETWEEN 2 AND 5 INCHES. OVER THE FAR EAST PLAINS...1 TO 2
INCHES WILL BE POSSIBLE.
THE MOUNTAINS WILL CONTINUE TO SEE SNOW...HOWEVER THE SNOW WILL END
FROM S TO N ACROSS THE C MTNS LATER TONIGHT. OVERALL ANOTHER 6 TO
12 INCHES OF SNOW IS LIKELY OVER THE CONTDVD REGION
TEMPS TONIGHT WILL BE COLD ONCE AGAIN ACROSS THE ENTIRE REGION.
SINGLE DIGITS WILL OCCUR ACROSS NEARLY ALL OF THE REGION EXCEPT
TEENS MAINLY IN THE SAN LUIS VALLEY. /HODANISH
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 412 AM MST SAT NOV 15 2014
...COLD SUNDAY THEN GRADUAL WARMING...
SNOW WILL LINGER ALONG THE SOUTHERN BORDER AREAS EARLY
SUNDAY...BUT SHOULD MOSTLY END BY NOON AS PROGRESSIVE
SHORTWAVE MOVES ON THROUGH. NEW SHOT OF ARCTIC AIR WILL
BRING ONE MORE REALLY COLD DAY SUNDAY BUT THEN THINGS WILL
START TO WARM UP AND DRY OUT FOR MOST OF THE UPCOMING WEEK.
THE WARM UP MAY START A LITTLE SLOW ON MONDAY AS SNOW COVER AND
LIGHT PRESSURE GRADIENTS WILL TEND TO KEEP SURFACE INVERSIONS IN
PLACE THROUGH THE DAY. BY TUESDAY...IT LOOKS LIKE WE SHOULD SEE A
LITTLE BETTER MIXING AS DOWNSLOPE PRESSURE GRADIENTS DEVELOP. THIS
SHOULD HELP BRING CHINOOK BREEZES OFF THE MOUNTAINS TO START
WARMING THE AIR.
COULD BE A LITTLE SET BACK WEDNESDAY AS THE MODELS ARE SHOWING A
WEAK SURFACE HIGH DROPPING THROUGH THE PLAINS THIS DAY. THIS COULD
REESTABLISH INVERSIONS IF THERE IS ENOUGH COOLING WITH THE HIGH
AND IF THERE IS ANY SNOW COVER REMAINING.
THURSDAY AND ESPECIALLY FRIDAY...IT LOOKS LIKE SOME WEAK ENERGY
FROM THE PACIFIC WILL START MOVING BACK INTO THE REGION. THIS
ENERGY COULD SPREAD SOME SNOW SHOWERS INTO THE CONTINENTAL DIVIDE
THURSDAY...AND EAST TO THE REST OF THE MOUNTAINS AND PIKES PEAK
REGION ON FRIDAY. THE APPROACHING ENERGY DOESN`T LOOK STRONG AT
THIS POINT SO FORECAST CONFIDENCE IS LOW AT THIS TIME. TEMPERATURES
WILL LIKELY REMAIN MILD THURSDAY...BUT THEN START TO COOL ON
FRIDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 412 AM MST SAT NOV 15 2014
KCOS...ARCTIC FRONT WILL CROSS KCOS AOA NOONTIME...18-19Z. WINDS
WILL SHIFT TO NORTH THAN NORTH-NORTHEAST AND BECOME GUSTY. COULD SEE
SOME SNOW SHOWERS BY MID AFTERNOON BUT EXPECT BRUNT OF IT WILL OCCUR
MORE TOWARDS SUNSET. LIFR CONDITIONS WILL BE POSSIBLE/LIKELY BETWEEN
00Z-09Z AS STEADY SNOW IS EXPECTED.
KPUB...ARCTIC FRONT WILL CROSS KPUB AOA 19-20Z WITH WINDS QUICKLY
SHIFTING TO THE NORTHEAST AND THEN EAST. PRECIP WILL LIKELY DEVELOP
AFTER SUNSET AND THERE IS A HIGH PROBABILITY THAT IT WILL SNOW...AND
IT IS EXPECTED TO ACCUMULATE TO 2-4 INCHES. LIFR CONDITIONS LIKELY
ONCE SNOW STARTS. IT WILL LAST THROUGH THE NIGHT ENDING AROUND
SUNRISE.
KALS...LOW CIGS THIS MORNING SHOULD BREAK UP ABOUT 1-2HRS AFTER
SUNRISE AS WEST WINDS INCREASE. VFR EXPECTED THROUGH THE REST OF THE
DAY WITH PRECIP DEVELOPING AFTER MIDNIGHT. SNOW WILL LIKELY
ACCUMULATE AT KALS WITH 1-2" ANTICIPATED. CIGS LIKELY WILL GO LIFR
AFTER MIDNIGHT.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 5 PM THIS AFTERNOON TO 9 AM MST
SUNDAY FOR COZ072>075-079-080-087-088.
WINTER STORM WARNING UNTIL 5 AM MST SUNDAY FOR COZ058-060-066-
068.
&&
$$
UPDATE...KT
SHORT TERM...HODANISH
LONG TERM...LW
AVIATION...HODANISH
AREA FORECAST DISCUSSION
NWS DES MOINES IA
1208 PM CST SAT NOV 15 2014
.UPDATE...
ISSUED AT 1207 PM CST SAT NOV 15 2014
SNOW CONTINUES TO EXPAND ACROSS CENTRAL IOWA. THE EARLY MORNING
ACTIVITY BROUGHT AROUND 3 INCHES OVER THE FAR NORTHWEST. THE
HEAVIES SNOWFALL RATES WILL SHIFT INTO CENTRAL IOWA THIS AFTERNOON
NEAR THE STRONGEST MID LEVEL FRONTOGENESIS. GRADUALLY COOLING
PROFILES WILL LEAD TO A DEEP DENDRITIC LAYER FROM NEAR 900 MB TO
500 MB. THESE TYPE EVENTS TEND TO BE EFFICIENT SNOW DEPTH PRODUCING
EVENTS WITH A PROLONGED PERIOD OF DENDRITES LEADING TO HIGH SNOW
RATIOS NEAR 20 TO 1. SNOW INTENSITIES WILL DIMINISH FOR A PERIOD
LATE AFTERNOON INTO THE EARLY EVENING. A VIGOROUS UPPER LEVEL
SHORT WAVE OVER WYOMING WITH KINEMATIC FORCING MOVING AHEAD
THROUGH CENTRAL SOUTH DAKOTA AND NORTHWEST NEBRASKA. THIS ENERGY
WILL ARRIVE THIS EVENING AND BRING A RENEWED BAND OF SNOW AND
ADDITIONAL ACCUMULATIONS. A WIDESPREAD 2 TO 4 INCHES STILL IS
EXPECTED WITH A FEW LOCATIONS APPROACHING 6 INCHES OVER THE
NORTHWEST.
&&
.SHORT TERM /TODAY/...
ISSUED AT 303 AM CST SAT NOV 15 2014
NO MAJOR CHANGES WITH ONGOING FORECAST FOR THE FIRST
SIGNIFICANT SNOWFALL OF THE SEASON AS MODELS REMAIN IN GOOD
AGREEMENT WITH EXPECTED SNOW TODAY. USED A BLEND OF THE
HRRR/HOPWRF FOR TIMING OF PRECIP AND NAM/ECMWF TEMPS.
BROAD ISENTROPIC LIFT AND DECENT MOISTURE TRANSPORT DEVELOP OVER
WESTERN TO NORTHWEST IOWA THIS MORNING AND QUICKLY BLOSSOMS ACROSS
THE REMAINDER OF THE STATE THIS AFTERNOON. ONE MINOR CHANGE WAS
START THE SNOW A LITTLE SOONER THIS MORNING OVER THE WEST TO
NORTHWEST AS SNOW ALREADY DEVELOPING ALOFT AND SNOW SHOULD START
REACHING THE SURFACE BETWEEN 12-14Z THIS MORNING. THE 15.03Z
HOPWRF AND 15.05Z HRRR HAVE SNOW MOVING INTO THE WESTERN EDGES OF
THE FORECAST AREA BETWEEN 13-15Z. THE FORECAST SOUNDINGS ACROSS
NORTHERN IOWA BECOME COMPLETELY SATURATED BY 17-18Z TODAY AND THE
STRONGER OMEGA IS JUST AT THE TOP EDGE OF THE DENDRITIC LAYER BUT
ENOUGH OVERLAP TO SEE SOME DECENT FLAKES...AND THUS SLIGHTLY
HIGHER SNOW ACCUMULATION THIS AFTERNOON OVER NORTHERN IOWA. RAP IS
A BIT LESS WITH THE FORCING THAN THE NAM/GFS AND HAS SLIGHTLY
LOWER SNOW AMOUNTS GOING...BUT STILL DEPICTS ENOUGH SNOW TO
WARRANT ADVISORY. FURTHER SOUTH...SOUNDINGS NOT TOO DISSIMILAR
THAN NORTHERN IOWA...WITH THE MAIN DIFFERENCE BEING JUST SLIGHTLY
LESSER FORCING WITHIN THE DENDRITIC LAYER. THIS RESULTING IN LESS
SNOW AMOUNTS OVER THE SOUTHERN TWO-THIRDS OF THE FORECAST AREA.
LEANED TOWARD A BLEND OF THE WARMER NAM/ECMWF FOR TEMPERATURES
TODAY. THIS RESULTED IN SNOW RATIOS AROUND 17:1 TO 18:1 OVER
NORTHERN IOWA AND 15:1 TO 16:1 ACROSS THE SOUTH...BASED ON 925M
TO 700MB THICKNESS. HAVE 100 POPS GOING MUCH OF THE AFTERNOON WITH
HIGH CONFIDENCE ALL OF CENTRAL IOWA WILL BE SNOWING BY OR SHORTLY
PAST 18Z. VERY LITTLE WIND TODAY BUT WITH THE FLUFFY SNOW TYPE
EXPECTED AND AT TIMES FALLING MODERATELY...THIS SHOULD BE ENOUGH
TO CAUSE SOME VISIBILITY RESTRICTION WITH A 6-9 KNOT WIND.
.LONG TERM /TONIGHT THROUGH FRIDAY/...
ISSUED AT 303 AM CST SAT NOV 15 2014
ACTIVE WEATHER WILL CONTINUE THROUGH THE WEEKEND AND EARLY NEXT
WEEK FOLLOWING TONIGHTS SYSTEM...ANOTHER INTENSE UPPER LEVEL LOW
WILL DROP SOUTH INTO THE NORTHERN GREAT LAKES SUNDAY NIGHT AND
MONDAY MORNING. TONIGHT...SYSTEM EXITING THE AREA TO THE EAST
DURING THE EVENING HOURS. BEST FORCING ALONG H500 AND SFC TROUGH
NEAR 00Z FOCUSING ON H700 BOUNDARY ACROSS NORTHERN IOWA. THROUGH
06Z THIS H700 BOUNDARY PUSHES EAST WITH TROUGH RESULTING IN
LESSENING FORCING WEST OF I35 DURING THE LATE EVENING. BY 12Z BEST
FORCING EAST OF THE AREA WITH SOME RESIDUAL LIGHT SNOW/FLURRIES
OVER THE NORTHEAST ENDING QUICKLY WITH CLOUDS DEPARTING IN THE
MORNING SUNDAY. SNOW RATIOS OF 18 TO 20:1 AND EXPECTED QPF AMOUNT
YIELD SNOWFALL AMOUNTS OF UP TO ANOTHER 1.5 INCHES TONIGHT DURING
THE EVENING AND OVERNIGHT HOURS. FORTUNATELY THE WINDS WILL BE
LIGHT DURING THE EVENT...SO BLOWING SNOW WILL NOT BE AN ISSUE
TONIGHT. WITH CLEARING BY MORNING...LOWS WILL QUICKLY FALL
NORTHWEST AND WEST INTO THE SINGLE DIGITS WITH TEENS I35 EAST.
SUNDAY WILL INITIALLY SEE SOME SUNSHINE BETWEEN WAVES BUT CLOUDS
WILL INCREASE WEST DURING THE AFTERNOON. WITH H850 TEMPS IN THE
-10C TO -12C RANGE AND WESTERLY WINDS...TEMPERATURES WILL BE
TOLERABLE IN THE MID 20S OVER MOST OF THE AREA. AN APPROACHING
COLD FRONT WILL SPREAD CLOUDS ACROSS THE REGION THROUGH EARLY
EVENING. THE SECOND STRONG H500 LOW WILL FORCE A BULGE OF COLD AIR
QUICKLY SOUTHEAST INTO WESTERN IOWA SUNDAY EVENING WITH RATHER
STRONG COLD AIR ADVECTION AND INCREASING WINDS ALOFT. BY 12Z H850
TEMPS WILL HAVE FALLEN ANOTHER 8 TO 10C WITH READINGS FROM -16C TO
-20C. THROUGH THE DAY MONDAY CLOUD COVER WILL OVERTAKE THE AREA
WITH H850 TEMPS SETTLING TOWARD -18C TO -20C REGION WIDE. MODELS
HAVE BEEN CONSISTENT WITH STEEPENING LAPSE RATES NEAR 15Z AND
STRONG MIXING THROUGH THE DAY...POTENTIAL FOR SNOW SHOWERS ACROSS
THE NORTHEAST WITH FLURRIES CENTRAL AND SOUTH. ALL IN ALL...MONDAY
IS LOOKING RATHER UNPLEASANT. POTENTIAL FOR 15 TO 25 MPH WINDS
WITH GUSTS TO NEAR 35 MPH AT TIMES. THIS WILL CAUSE PATCHY TO
AREAS BLOWING SNOW OVER MUCH OF THE NORTHEAST HALF OF THE AREA
WITH REDUCTIONS TO VISIBILITY. HEADLINES MAY BE NEEDED AGAIN ON
MONDAY FOR THE COMBINATION OF WIND...BLOWING SNOW...AND COLD. HAVE
EXPANDED THE POTENTIAL FOR LIGHT PRECIP AND BLOWING SNOW MONDAY
ACROSS THE AREA. HIGHS WILL RECOVER LITTLE FROM FRIGID MORNING
LOWS IN THE SINGLE DIGITS TO LOWER TEENS. BY AFTERNOON HIGHS NORTH
WILL REACH THE LOWER TEENS TO THE LOWER 20S IN THE SOUTHEAST. TO
TOP OFF THE WONDERFUL DAY...MINIMUM RECORD HIGHS LOOK LIKELY TO BE
SET AT MANY LOCATIONS...ONE WHICH HAS NOT BEEN SEEN SINCE THE
1890S AND MANY SINCE THE 1950S. IN FACT...OUR HIGHS MONDAY WOULD
STILL BE ABOUT 10 TO 15 DEGREES BELOW OUR COLDEST AVERAGE HIGHS
FOR THE NORMALLY COLDEST WINTER DAY OF THE YEAR...OR ABOUT 30
DEGREES BELOW OUR NORMAL FOR 11/17. WE HAVENT HAD HIGHS THIS COLD
SINCE EARLY MARCH OF 2014. TUESDAY WILL BEGIN QUITE COLD WITH A
RIDGE JUST EDGING INTO THE AREA BUT WARM BY AFTERNOON. QUICKLY
ANOTHER CLIPPER OVER THE NORTHERN PLAINS WILL MODERATE THE AIRMASS
WITH BRISK WEST WINDS DEVELOPING DURING THE DAY. TEMPS WILL RISE
INTO THE 20S. ANOTHER ARCTIC FRONT WILL DROP SOUTH INTO THE AREA
TUESDAY NIGHT BUT THE AIRMASS WILL NOT BE QUITE AS COLD AS THE
PREVIOUS. THE REMAINDER OF THE WEEK FEATURES A SERIES OF ARCTIC
SHORT WAVES ROTATING AROUND THE HUDSON BAY PARENT H500
LOW...PULLING ADDITIONAL COLD AIR TOWARD THE GREAT PLAINS. NEXT
WEEK WILL FEATURE DAYS WITH CLOUD COVER MIXED WITH SOME SUNSHINE
AND CHILLY READINGS. FORTUNATELY BY LATE IN THE EXTENDED...TOWARD
SATURDAY THE CROSS POLAR FLOW CUTS OFF...THE H500 RIDGE ACROSS THE
WEST COAST BREAKS DOWN AND MORE ZONAL FLOW RESULTS OVER THE
ROCKIES. THIS WILL CAUSE CHINOOKS COMPRESSIONAL HEATING OVER THE
PLAINS AND MODERATE HIGHS TO ABOVE FREEZING. FROM WEDNESDAY
THROUGH FRIDAY HIGHS WILL APPROACH THE 30 DEGREE MARK WITH LOWS
MODERATING INTO THE TEENS OVER THE AREA. LITTLE PRECIPITATION IS
EXPECTED FOR MUCH OF THE PERIOD NEXT WEEK.
&&
.AVIATION...15/18Z
ISSUED AT 1147 AM CST SAT NOV 15 2014
CONDITIONS WILL CONTINUE TO DETERIORATE ACROSS SITES THIS
AFTERNOON AS LOWER CIGS AND SNOW MOVE INTO THE AREA. A PERIOD OF
IMPROVED VSBYS EXPECTED BY LATE AFTERNOON THROUGH EARLY EVENING
BEFORE ANOTHER BAND OF SNOW ARRIVES. CIGS WILL RANGE FROM IFR TO
MVFR THROUGH MUCH OF THE PERIOD. SOUTHEAST WINDS WILL BECOME
WEST/NORTHWEST LATE TONIGHT.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR ADAIR-
ADAMS-APPANOOSE-AUDUBON-BLACK HAWK-BOONE-BREMER-BUTLER-CALHOUN-
CARROLL-CASS-CERRO GORDO-CLARKE-CRAWFORD-DALLAS-DAVIS-DECATUR-
EMMET-FRANKLIN-GREENE-GRUNDY-GUTHRIE-HAMILTON-HANCOCK-HARDIN-
HUMBOLDT-JASPER-KOSSUTH-LUCAS-MADISON-MAHASKA-MARION-MARSHALL-
MONROE-PALO ALTO-POCAHONTAS-POLK-POWESHIEK-RINGGOLD-SAC-STORY-
TAMA-TAYLOR-UNION-WAPELLO-WARREN-WAYNE-WEBSTER-WINNEBAGO-WORTH-
WRIGHT.
&&
$$
UPDATE...DONAVON
SHORT TERM...PODRAZIK
LONG TERM...REV
AVIATION...DONAVON
AREA FORECAST DISCUSSION
NWS GOODLAND KS
210 PM MST SAT NOV 15 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 210 PM MST SAT NOV 15 2014
THE UPPER TROUGH AXIS MOVES SOUTH ACROSS THE CENTRAL PLAINS TONIGHT
AND SUNDAY WITH NORTHWEST FLOW FOLLOWING. SURFACE HIGH PRESSURE
WILL BUILD SOUTHEAST INTO THE CENTRAL PLAINS THROUGH THIS TIME.
PLAN TO GO WITH CHANCE AND LIKELY POPS TONIGHT ACROSS THE FA AS
DYNAMICS AND MOISTURE MOVE FROM NORTH TO SOUTH. THE DYNAMICS MOVE
INTO THE SOUTHWEST PORTION OF THE FA AFTER 06Z AND SO WILL SHIFT
LIKELY POPS OVER THE EXTREME SOUTHWEST AFTER MIDNIGHT WITH
DECREASING POPS TO THE NORTH. MOISTURE IS LIMITED WITH THIS SYSTEM
SO WILL KEEP SNOW AMOUNTS ON THE LIGHT SIDE OR A FEW TENTHS OF AN
INCH. THE SOUTHWEST WILL HAVE THE BEST CHANCE OF ACCUMULATING SNOW
WITH AROUND A HALF INCH POSSIBLE THERE.
MIN TEMPERATURES WILL FALL INTO THE SINGLE DIGITS OVERNIGHT AND WITH
NORTHWEST WIND SOME VERY COLD WIND CHILL TEMPERATURES WILL BE
REACHED. WIND CHILL TEMPERATURES DROP BELOW WIND CHILL ADVISORY
CRITERIA TONIGHT AND SUNDAY MORNING ACROSS THE NORTH AND WEST ZONES.
PLAN TO ISSUE A WIND CHILL ADVISORY TO COVER THIS. SEE DETAILS
BELOW. MAX TEMPERATURES SUNDAY SHOULD RISE TO THE UPPER 20S WITH
TEMPERATURES NEAR 30 OVER THE SOUTHEAST ZONES.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 210 PM MST SAT NOV 15 2014
SEVERAL DRY DAYS ARE EXPECTED FOR THE ENTIRE FORECAST AREA GOING
INTO THE BEGINNING OF NEXT WEEK. THE TRI STATE REGION WILL BE IN
BETWEEN A BROAD/DEEP 500 MB TROUGH THAT SETS UP OVER THE EASTERN
PORTION OF THE COUNTRY SUNDAY NIGHT INTO MONDAY...AND A BUILDING H5
RIDGE OVER THE WESTERN HALF OF THE COUNTRY. RIDGE DOES SHIFT
EASTWARD INTO THE ROCKIES BY MIDWEEK..WITH 500/700 MB TROUGH COMING
OFF THE PACIFIC AND THRU RIDGE...INTO ROCKIES LATE FRIDAY INTO
SATURDAY.
DOWN TO THE SURFACE...HIGH PRESSURE WILL BE MOST PREVALENT DURING
THIS TIMEFRAME. ONLY CHANCE FOR PRECIPITATION BEFORE NEXT WEEKEND
WILL BE ON WEDNESDAY AS FRONTAL BOUNDARY/TROUGH SHIFTS OFF THE
ROCKIES AND EASTWARD TO THE MISSISSIPPI VALLEY. WITH HIGH PRESSURE
SE OF THE AREA DURING THIS TIME AND BROAD WNW FLOW...LITTLE QPF
POTENTIAL...SO WILL HAVE DRY. THE NEXT CHANCE FOR PRECIPITATION WILL
BE AT THE END OF NEXT WEEK WHEN MID LEVEL SHORTWAVE MOVES EAST OFF
THE PACIFIC. DRY AIR OUT AHEAD OF IT...COMBINED WITH ITS TRIP THRU
THE ROCKIES...WILL LIMIT QPF POTENTIAL BUT OUTSIDE CHANCE OF A FEW
LATE DAY SHOWERS.
WITH LACK OF ANY APPRECIABLE RAIN OR SNOW NEXT WEEK...THE MAIN
FOCUS WILL BE SHIFT IN TEMPERATURES. WITH 850/925 MB TEMPS RANGING
FROM -2C TO -4C ON MONDAY...UP TO +9C TO +12C ON FRIDAY INTO
SATURDAY...THE FORECAST AREA WILL SEE BELOW NORMAL TEMPS SHIFTING TO
ABOVE NORMAL READINGS ESPECIALLY DURING THE DAY. TRI STATE REGION
WILL SEE HIGHS NEAR 30F ON MONDAY TO MID 40S BY MIDWEEK TO ALMOST
MID 50S FOR THE END OF NEXT WEEK. THIS WOULD GIVE WEDNESDAY INTO
SATURDAY WITH HIGHS 5 TO 10 DEGREES ABOVE NORMAL. WITH HIGH PRESSURE
MOST PREVALENT...CLEAR SKIES AT NIGHT WILL HAVE OVERNIGHT LOWS
RANGING FROM THE TEENS TO START THE WEEK...TO THE 20S FOR THE REST
OF THE TIME.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1030 AM MST SAT NOV 15 2014
CIGS ARE PROGRESSIVELY LOWERING AT KGLD AND CONTINUE MVFR AT KMCK
AT MIDDAY AS THE UPPER TROUGH MOVES INTO THE NORTHERN AND CENTRAL
PLAINS TODAY. THE SREF AND HRRR BRING A SWATH OF LIGHT SNOW INTO
THE ARE THIS AFTERNOON WHICH SHOULD IMPACT BOTH TERMINALS WITH
MVFR CONDITIONS. LIGHT SNOW SHOULD END AT BOTH SITES EARLY THIS
EVENING WITH VFR CONDITIONS OCCURING BEHIND THE COLD FRONT.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...WIND CHILL ADVISORY FROM 9 PM MST /10 PM CST/ THIS EVENING TO 9
AM MST /10 AM CST/ SUNDAY FOR KSZ001>003-013.
CO...WIND CHILL ADVISORY FROM 9 PM THIS EVENING TO 9 AM MST SUNDAY
FOR COZ090-091.
NE...WIND CHILL ADVISORY FROM 9 PM MST /10 PM CST/ THIS EVENING TO 9
AM MST /10 AM CST/ SUNDAY FOR NEZ079>081.
&&
$$
SHORT TERM...FS
LONG TERM...JN
AVIATION...FS
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1035 AM MST SAT NOV 15 2014
.SHORT TERM...(TODAY THROUGH MONDAY NIGHT)
ISSUED AT 404 AM MST SAT NOV 15 2014
MAIN FORECAST CONCERN WILL BE WINTER WEATHER EVENT OCCURRING
THROUGH TONIGHT. SATELLITE CONTINUING TO SHOW AN AMPLIFIED PATTERN
FROM THE EASTERN PACIFIC INTO EASTERN NORTH AMERICA. CURRENTLY
NEARLY ZONAL FLOW OVER OUR AREA WITH MULTIPLE SMALL SCALE WAVES
EMBEDDED WITHIN THAT FLOW. STRONG...COLD AND RATHER COMPLEX UPPER
TROUGH IS MOVING THROUGH THE NORTH CENTRAL OF THE COUNTRY.
SATELLITE ALSO SHOWING DRY MID LEVEL AIR MASS IN PLACE AHEAD OF
INCOMING NORTHERN TROUGH. ANOTHER STRONG COLD FRONT IS APPROACHING
FROM THE NORTH.
AT JET LEVEL...MODELS LOOKED LIKE THEY INITIALIZED FINE. AT MID
LEVELS...THE GFS WAS DOING A LITTLE BETTER THAN THE ECMWF AND
CANADIAN. THE SREF WAS DOING THE BEST AT THE SURFACE. ALL THE
MODELS WERE OKAY ON THE LOW LEVEL THERMAL FIELD.
TODAY/TONIGHT...THE DAY STARTS OUT WITH AREA IN SUBSIDENCE FROM
DEPARTING JET. AFTER THIS MODELS DISAGREE WHERE THE MAIN JET
ENERGY WILL BE THROUGH THE REST OF THE PERIOD. BY 18Z IT LOOKS
LIKE A LEFT FRONT QUADRANT WILL BEGIN AFFECTING THE AREA. BY LATE
IN THE AFTERNOON INTO THE EVENING...THERE MAY BE A RIGHT REAR
QUADRANT ACROSS THE SOUTHEASTERN PORTION OF THE AREA. AFTER THAT
THE JET IS WELL SOUTH.
CURRENTLY INITIAL SHORTWAVE TROUGH IS MOVING THROUGH AND PRODUCING
LIGHT SNOW OVER SOUTHERN AND EASTERN SECTIONS. MODELS HAVE A GOOD
HANDLE ON THIS INITIAL SHORTWAVE TROUGH. CURRENT RADAR SHOWS THAT
THE MOST INTENSE SNOWFALL IS TO THE SOUTH OF AREA AND MOVING
THROUGH RATHER QUICKLY. ALL NIGHT THE HRRR HAS BEEN CATCHING THE
CURRENT RADAR TRENDS EXTREMELY WELL AND IT ALSO MATCHES UP WELL
WITH THE ABOVE MENTIONED MID AND UPPER LEVEL LIFT. OTHER OUTPUT IS
TOO FAR NORTH WITH THE PRECIPITATION SHIELD. SO WILL LEAN HEAVILY
ON THE HRRR FOR PRECIPITATION EARLY ON AND THEN TREND MORE TOWARD
THE CANADIAN/ECMWF AFTER THAT.
SO LITTLE TO NO SNOW FALL WILL END UP FALLING OVER THE WESTERN
HALF TO TWO THIRDS THIS MORNING WITH MOST OF THE SNOW OCCURRING IN
THE EASTERN SIX COUNTIES THROUGH MID MORNING. UPSTREAM SATELLITE
IS SHOWING A CLEARING TREND BEHIND THIS EXITING SHORTWAVE AND A
DRY AIR MASS IN ADVANCE OF THE NEXT SHORTWAVE TROUGH. AFTER THE
SNOW ENDS THIS MORNING...THE NEXT BATCH OF LIGHT SNOW WILL DEVELOP
TO OUR NORTH AND NORTHWEST BY LATE IN THE MORNING TO EARLY
AFTERNOON. THIS AREA THEN MOVES ACROSS THE AREA THROUGH THE REST
OF THE NIGHT WITH THE MOST SNOWFALL OCCURRING BEFORE MIDNIGHT. IT
IS POSSIBLE THAT SOME LOCATIONS MAY NOT SEE ANY SNOW UNTIL LATER
THIS AFTERNOON TO EARLY THIS EVENING.
MODELS...ESPECIALLY THE GFS...TEND TO BE TOO DEEP WITH THE
MOISTURE AND THEREFORE OVERPRODUCES PRECIPITATION. THE DRIER AIR
MASS UPSTREAM MAKES SENSE SINCE MOISTURE IN THE WESTERLY FLOW
ALOFT IS GETTING WRUNG BY THE HIGHER TERRAIN OVER COLORADO. SO PER
THE REASONING GIVEN ABOVE...SNOWFALL AMOUNTS WILL BE MUCH LIGHTER
THAN PREVIOUSLY EXPECTED WITH TOTAL AMOUNTS NOW ANTICIPATED TO BE
AROUND AN INCH OR LESS. IT IS ALSO POSSIBLE THAT WHEN THE COLD
FRONT MOVES THROUGH LATER TODAY...THAT LITTLE IF ANY SNOW WILL BE
ON THE GROUND. ALSO CONSIDERING WHAT LITTLE SNOW HAS ALREADY
FALLEN AND THAT THERE WILL BE A SIGNIFICANT LULL BEFORE THE NEXT
SNOWFALL STARTS...HAVE DECIDED TO CANCEL THE WINTER WEATHER
ADVISORY. IF SNOWFALL ENDS UP BEING WORSE THAN CURRENTLY
EXPECTED...THEN A MORE SHORT TERM ADVISORY CAN BE ISSUED TO HANDLE
THAT SINCE NOTHING IS GOING ON AT THIS TIME.
NOW FOR TEMPERATURES. JUST LIKE LAST NIGHT...MODELS ARE TOO COOL
WITH THE CURRENT TEMPERATURES DUE TO CLOUD COVER AND CONTINUED
WARM AIR ADVECTION. FRONT IS ALSO EXPECTED TO ARRIVE LATER AND
WILL NOT MOVE THROUGH THE EASTERN PORTION OF THE AREA UNTIL THIS
AFTERNOON. THERE ALSO MAY BE ENOUGH BREAKS IN THE CLOUD COVER TO
ALLOW SOME SUNSHINE TO OCCUR. A LOT OF THE OUTPUT IS SAYING
WARMER AND TRENDED IN THAT DIRECTION.
SUNDAY/SUNDAY NIGHT...DRY CONDITIONS EXPECTED THROUGH THE PERIOD.
SHOULD SEE A DECENT AMOUNT OF SUN WITH WINDS BEING MOSTLY FROM A
DOWNSLOPE DIRECTION. MODELS ARE SHOW TEMPERATURES WARMER THAN
YESTERDAY. MODELS HAVE HAD A RECENT COOL BIAS AS WELL. SO WENT
NEAR THE WARMER GUIDANCE.
MONDAY/MONDAY NIGHT...STRONG UPPER SYSTEM DIGS INTO THE NORTH
CENTRAL PORTION OF THE COUNTRY JUST BEFORE AND DURING THIS PERIOD.
THIS PUSHES ANOTHER COLD FRONT THROUGH THE AREA AND SHOULD MAKE
FOR COOLER TEMPERATURES COMPARED TO SUNDAY MAXES. HOWEVER...THERE
IS A BIG DIFFERENCE IN THE AMOUNT OF COOLING INDICATED BY THE
MODELS. DID NOT GO WITH THE COLDEST GUIDANCE BUT TRENDED IN THE
COLDER DIRECTION.
.LONG TERM...(TUESDAY THROUGH FRIDAY)
ISSUED AT 404 AM MST SAT NOV 15 2014
COMPARING TONIGHTS MODELS RUN TO LAST NIGHTS THE LONG WAVE RIDGE
OVER THE WEST COAST OF THE UNITED STATES WILL STILL MOVE EAST AND BE
LOCATED OVER THE ROCKIES BY FRIDAY. HOWEVER... UNLIKE LAST NIGHTS
RUN... WHERE THE RIDGE LOOKED LIKE IT WOULD FLATTEN... IT NOW
SEEMS IT WILL MAINTAIN ITS AMPLITUDE. THIS WILL PRODUCE A
PREDOMINATELY NORTHWESTERN UPPER LEVEL FLOW OVER THE TRI-STATE
AREA DURING THE EXTENDED.
YESTERDAYS QUESTION WAS WHEN WILL THE NEXT FRONT PASS OVER THE AREA.
TONIGHTS RUN OF THE GFS... NAVGEM AND ECMWF ARE IN BETTER AGREEMENT
ON THIS FRONT COMPARED TO LAST NIGHTS RUN. THEY ALL HAVE THE FRONT
PASSING OVER THE AREA ON THE 19TH BETWEEN 00Z AND 06Z. THEY ALSO
SHOW THIS SYSTEM TO BE A DRY ONE AND WILL HAVE LITTLE TO NO EFFECT
ON THE TEMPERATURES. IT DOES SHOW A SHIFT IN THE WINDS FOLLOWED BY
LIGHT WINDS AS HIGH PRESSURE BUILDS IN BEHIND IT FOR THE REST OF THE
EXTENDED.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1030 AM MST SAT NOV 15 2014
CIGS ARE PROGRESSIVELY LOWERING AT KGLD AND CONTINUE MVFR AT KMCK
AT MIDDAY AS THE UPPER TROUGH MOVES INTO THE NORTHERN AND CENTRAL
PLAINS TODAY. THE SREF AND HRRR BRING A SWATH OF LIGHT SNOW INTO
THE ARE THIS AFTERNOON WHICH SHOULD IMPACT BOTH TERMINALS WITH
MVFR CONDITIONS. LIGHT SNOW SHOULD END AT BOTH SITES EARLY THIS
EVENING WITH VFR CONDITIONS OCCURING BEHIND THE COLD FRONT.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...BULLER
LONG TERM...BDW/BULLER
AVIATION...FS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
259 PM EST SAT NOV 15 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 416 AM EST SAT NOV 15 2014
A QUIET START TO THE SHORT TERM FORECAST THIS MORNING...AS THE AREA
IS ON THE NORTHEAST EDGE OF A HIGH CENTERED FROM THE MID/UPPER
MISSISSIPPI VALLEY TO THE OHIO RIVER VALLEY. THIS HAS LED TO A
CLEAR AND COLD NIGHT ACROSS AT LEAST HALF OF THE CWA. WHERE WINDS
HAVE DECOUPLED (GENERALLY ACROSS THE INTERIOR WEST AND NEAR THE
WISCONSIN BORDER)...TEMPERATURES HAVE FALLEN INTO THE SINGLE
DIGITS BELOW ZERO. MEANWHILE...OVER THE CENTRAL AND EAST WHERE THE
WINDS HAVE BEEN STAYING UP...TEMPERATURES HAVE BEEN IN THE UPPER
SINGLE DIGITS ABOVE ZERO TO MID TEENS.
OVER LAKE SUPERIOR AND THE KEWEENAW...COLD AIR CONTINUING TO FLOW
OVER THE RELATIVELY WARM WATERS OF LAKE SUPERIOR WAS PRODUCING
MAINLY LAKE EFFECT CLOUDS THIS PAST EVENING AND INTO THE EARLY
OVERNIGHT HOURS. BUT STARTED SEEING WEAK LAKE EFFECT BANDS
OVER EASTERN LAKE SUPERIOR ON THE CANADIAN RADAR AT MONTREAL RIVER
SHORTLY AFTER MIDNIGHT. INVERSION IS RIGHT AT 875-850MB ON 00Z
KGRB/KINL SOUNDINGS AND THE LIMITED MOISTURE ON THE NORTH EDGE OF
THE HIGH HAVE BEEN THE MAIN LIMITING FACTORS TO LAKE EFFECT SNOW
EARLY THIS MORNING. KMQT VWP HAS BEEN SHOWING THE WINDS A LITTLE
MORE OUT OF THE WEST-NORTHWEST AND CONTRIBUTING TO THE LAKE EFFECT
CLOUDS NOSING SOUTHEAST INTO BARAGA...SOUTHERN HOUGHTON...AND EVEN
FAR NORTHERN IRON COUNTY EARLY THIS MORNING. BUT AS WE HEAD INTO
THE MORNING HOURS...MODELS SHOWING THE WINDS GOING BACK TO A MORE
WESTERLY AND POTENTIALLY WEST-SOUTHWESTERLY DIRECTION AND CONFINING
THE LAKE EFFECT CLOUDS AND SNOW POTENTIAL TO THE KEWEENAW AND OFF
THE SHORELINE FROM GRAND MARAIS EASTWARD. THIS WILL ALSO BE AIDED
BY THE LAND BREEZE THAT HAS DEVELOPED ALONG THE EASTERN U.P.
SHORELINE AND WILL AID IN KEEPING THE BANDS OFFSHORE THERE. THE
COVERAGE OF THE SHOWERS IS A LITTLE BIT OF A CONCERN DUE TO THE
LIMITED MOISTURE...BUT WOULD EXPECT SOME UPTICK IN THE SNOW SHOWERS
AS 875MB TEMPERATURES FALL FROM -11C ON THE RAP ANALYSIS TO -13/-14C
BY THIS AFTERNOON. THUS...WILL CONTINUE TO SHOW POPS RAMPING UP TO
HIGH CHANCES OVER THE KEWEENAW. WITH MUCH OF THE LAKE EFFECT CLOUD
BELOW THE DGZ...WILL KEEP SNOW RATIOS ON THE LOW END FOR LAKE EFFECT
AND ONLY HAVE ACCUMULATIONS AT A DUSTING TO AN INCH IN THAT AREA.
OVER THE REST OF THE AREA...EXPECT A SUNNY START TO THE DAY WHICH
WILL ALLOW TEMPERATURES TO RISE TO THE LOW-MID 20S THIS AFTERNOON.
EXPECT MORE OF A FILTERED SUNSHINE IN THE AFTERNOON AS HIGH CLOUDS
MOVE IN AHEAD OF THE WAVE BRUSHING THE AREA LATE TONIGHT.
HEADING INTO TONIGHT...FOCUS TURNS TO THE SHORTWAVE CURRENTLY
MOVING THROUGH WYOMING. THIS WAVE WILL QUICKLY SHIFT EAST THROUGH
NEBRASKA AND SOUTH DAKOTA TODAY AND THEN LIFT NORTHEAST ACROSS
NORTHERN LAKE MICHIGAN LATE TONIGHT AND SUNDAY MORNING. EXPECT THE
HIGH CLOUDS TO THICKEN THIS EVENING AND MID CLOUDS TO MOVE IN
DURING THE LATE EVENING AND OVERNIGHT. ANOTHER SHORTWAVE (CURRENTLY
IN COLORADO) WILL LIFT NORTHEAST OUT AHEAD OF THE MAIN WAVE AND
COULD PRODUCE A FEW SHOWERS AROUND MIDNIGHT. THE BETTER/MAIN
FORCING (GENERALLY ABOVE 700MB) COMES FROM THE SECOND SHORTWAVE AND
LOOKS TO STAY SOUTHEAST OF THE AREA...BUT DO EXPECT MENOMINEE COUNTY
AND AREAS ALONG THE LAKE MICHIGAN SHORELINE TO SEE THE BEST
OPPORTUNITY FOR ACCUMULATING SNOW. CURRENT FORECAST HAS SNOWFALL
AMOUNTS UP TO AN INCH OVER SOUTHERN MENOMINEE COUNTY AND TAPERING
OFF TO A HALF INCH OR LESS SOUTH OF A LINE FROM IRON MOUNTAIN TO
MANISTIQUE. SINCE THE NORTHERN EDGE OF THE FORCING WILL BE JUST
BRUSHING THE AREA...DO EXPECT A SHARP CUTOFF TO THE PRECIPITATION TO
THE NORTHWEST AND KEEP THE SNOW CHANCES TO THE SOUTHEAST OF A LINE
FROM MARQUETTE TO WATERSMEET. AS FOR THE LAKE EFFECT OVER THE
KEWEENAW...THIS WAVE WILL BACK THE LOW LEVEL WINDS FARTHER TO THE
SOUTHWEST AND FOCUS ANY LINGERING LAKE EFFECT TO THE FAR NORTHERN
PORTIONS OF THE KEWEENAW PENINSULA. ACCUMULATIONS WILL REMAIN LIGHT
AND BELOW 2 INCHES.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 258 PM EST SAT NOV 15 2014
UPPER LEVEL PATTERN TO BEGIN THE LONG TERM ON SUNDAY NIGHT SHOWS
AMPLIFIED PATTERN WITH RIDGE OVER WESTERN CONUS AND INTO WESTERN
CANADA AND DEEP TROUGHING DOWNSTREAM OVER CNTRL CONUS. MORE RIDGING
WILL BE IN PLACE DOWNSTREAM OVER THE EASTERN CONUS. TROUGH DEEPENS
OVER THE GREAT LAKES EARLY IN THE WEEK...THEN RELAXES SLIGHTLY
BEFORE MORE TROUGHING BRINGS ANOTHER SHOT OF ARCTIC AIR OVER THE
GREAT LAKES TOWARD END OF THE WEEK. JET ENERGY BECOMES MORE FOCUSED
ON LEADING EDGE OF TROUGHING BY NEXT WEEKEND ALLOWING THE TROUGH TO
MOVE EAST AND ALLOWING RIDGING WITH MODERATING TEMPERATURES TO
RETURN TO THE GREAT LAKES BEGINNING NEXT WEEKEND.
UNTIL THEN THE MAIN THEME OF THIS WEEK WILL BE COLD WITH LAKE EFFECT
SNOW SHOWERS. INITIALLY AN UPPER LOW AND ASSOCIATED SFC LOW WORKS
ACROSS LK SUPERIOR REGION ON MONDAY. TREND TOWARD A SLOWER FROPA
WITH THE SYSTEM. FRONT SHOULD SWEEP ACROSS WETSERN CWA AROUND
DAYBREAK ON MONDAY AND NOT REACH EASTERN CWA UNTIL MONDAY AFTN.
BLYR WINDS SHIFT NW BEHIND THE FRONT AND THERE IS SUFFICIENT DEEPER
MOISTURE TO H7-H6 FOR LAKE ENHANCED SNOW AS H85 TEMPS ARE AROUND
-15C. LARGE SCALE FORCING WILL MAINLY BE TO THE EAST OF MUCH OF UPR
MICHIGAN BY MONDAY AFTN...BUT EVEN THEN SOUNDINGS SHOW UNSTABLE
PROFILE SFC-H7 WITH SUFFICIENT MOISTURE AND STRONG ENOUGH WINDS TO
LEAD TO SNOW SHOWERS OVER MUCH OF UPR MICHIGAN. BY FAR THOUGH THE
BEST CHANCE OF SNOW SHOWERS WILL BE TIED TO LAKE EFFECT FOR NW FLOW
AREAS OVER WESTERN UPR MICHIGAN AND EVENTUALLY IN THE SNOW BELTS
OVER EAST HALF OF UPR MICHIGAN AS OVER-WATER INSTABILITY IS VERY
FAVORABLE WITH DELTA T/S OVER 20C AND LAKE EQ LEVELS OVER 15KFT.
CYCLONIC FLOW SFC-H7 WILL ONLY ENHANCE THE CONVERGENCE AND SNOW
SHOWER INTENSITY. EXPECT SOME OF THE HEAVIEST LAKE EFFECT SNOW TO
OCCUR MONDAY AFTN/MONDAY NIGHT AND INTO TUESDAY WHEN THE DEEPER
MOISTURE TO H7 IS PRESENT AND CYCLONIC FLOW IS STRONGEST. SFC-925MB
WINDS INDICATE AREAS FAVORED BY NNW FLOW WILL SEE THE MOST
CONCENTRATED LAKE EFFECT...HOWEVER H85-H7 WINDS ARE MORE FM THE
N-NNW...SO THIS COULD BRING PERIODS OF LAKE EFFECT INTO AREAS
FAVORED BY THAT FLOW REGIME AS WELL. OVERALL...MODERATE TO HEAVY
LAKE EFFECT SNOW IS EXPECTED ALONG MUCH OF LK SUPERIOR LATER MONDAY
INTO TUESDAY MORNING. MOISTURE OFF THE STILL OPEN WATERS OF LK
NIPEGON COULD ALSO SERVE AS ENHANCEMENT FACTOR THE LAKE EFFECT.
THERE ARE STILL TIMING AND LOCATION UNCERTAINTIES SO WILL NOT ISSUE
ANY LAKE EFFECT SNOW WATCHES YET BUT WILL CONTINUE TO MENTION THE
POTENTIAL FOR HEAVY LAKE EFFECT IN HAZARDOUS WEATHER OUTLOOK AND THE
EHWO GRAPHICS.
SHORTWAVE TROUGH MOVES EAST ON TUESDAY TAKING THE DEEP MOISTURE
STEADILY OUT OF THE UPPER GREAT LAKES BY AFTERNOON. ALL THE WHILE
EXPECT NW WINDS IN LAKE EFFECT MOIST LAYER TO BECOME MORE WESTERLY
BY LATE IN THE DAY...PUSHING THE LAKE EFFECT SNOW SHOWERS ACROSS
THE KEWEENAW AND ALONG LK SUPERIOR EAST OF MUNISING. AS ALLUDED TO
BEFORE...LARGE SCALE TROUGH IS RE-INFORCED LATER IN THE WEEK AS A
COUPLE OF SHORTWAVES DIVE ACROSS THE UPPER GREAT LAKES REGION.
POSSIBLE THAT COULD SEE A SWATH OF WIDESPREAD LIGHT SNOW AS THESE
WORK ACROSS LATE TUESDAY NIGHT INTO WEDNESDAY...THOUGH MOISTURE IS
REALLY LACKING AS H7 MIXING RATIOS ARE BARELY ABOVE 1G/KG SUGGESTING
JUST A DUSTING OF SNOW WOULD OCCUR AWAY FM THE GREAT LAKES. APPEARS
THAT THERE MAY BE BRIEF OPPORTUNITY FOR LAKE ENHANCED SNOW OFF LK
MICHIGAN AS WINDS BACK FM WSW TO SSW AS WITH FORCING PRESENT AND AS
H85 TEMPS ARE AROUND -10C. FOR MOST PART THOUGH...THINK BETTER LAKE
ENHANCEMENT STAYS JUST EAST OF THE CWA. AS SECOND SHORTWAVE MOVES
THROUGH LATER ON WEDNESDAY ALONG WITH SUB 1000MB SFC LOW AND COLD
FRONT...LIKELY WILL SEE ANOTHER ROUND OF MODERATE TO HEAVY LAKE
ENHANCED SNOW KICK UP AGAIN WITH H85 TEMPS AROUND -14C AND MORE
DEEPER MOISTURE THROUGH H7. BASED ON UNIDIRECTIONAL FLOW SFC-H7 THE
MOST SNOW WOULD OCCUR ESPECIALLY FOR AREAS FAVORED BY WNW WINDS.
LAKE EFFECT WILL BE ON THE MOVE AGAIN ON THURSDAY...HEADING TOWARD
AREAS FAVORED BY NORTHWEST WINDS. MID SHIFT HIGHLIGHTED THIS TIME
FRAME FOR HEAVY LAKE EFFECT SNOW POTENTIAL IN THE HWO AND EHWO
GRAPHICS. WILL FOLLOW SUIT WITH THIS FORECAST.
INSTENSITY FOR LAKE EFFECT BEGINS TO DIMINISH LATER THURSDAY AND
CERTAINLY BY FRIDAY AS SOUNDINGS INDICATE INVERSIONS LOWERING TO
AROUND 5KFT INSTEAD OF THE MORE ROBUST 10KFT+ THEY ARE FOR MOST OF
THE WEEK. MORE ANTICYCLONIC LOW-LEVEL FLOW WITH APPROACHING RIDGE
WILL ALSO KNOCK DOWN INTENSITY OF SNOW SHOWERS AND LEAD TO LESS
COVERAGE OF THE LAKE EFFECT.
WINDS BACK WSW-SW FRIDAY NIGHT INTO SATURDAY AS HIGH PRESSURE RIDGE
ARRIVES. BETWEEN BACKING WINDS AND WARMING TEMPS IN LOW-LEVELS...
LAKE EFFECT SNOW SHOWERS SHOULD END BY SATURDAY. 12Z GFS SHOWS
DECENT WARM AND MOIST ADVECTION SNOW ON BACK SIDE OF RIDGE. NO
CONSISTENCY WITH PREVIOUS RUNS THOUGH NOR THE ECMWF WHICH HAS THE
AREA MAINLY DRY. 12Z GFS REPRESENTS JUST A HIGHER-END SNOW ENSEMBLE
MEMBER AT THIS POINT. GIVEN THE DEPTH OF THE COLD AIR DOME THAT WILL
BE RETREATING BY THAT TIME...COULD SEE SOME ISENTROPIC LIFT TYPE
SNOW...BUT JUST NOT SURE IT WILL BE TO THE EXTENT THE GFS SHOWS.
WILL GO WITH CONSENSUS OF MODELS ATTM AND WE CAN FINE TUNE FOR LATER
FORECASTS. WARMING TREND DOES APPEAR TO BEGIN ON SATURDAY WHICH MAY
RESULT IN TEMPS JUST BEYOND THE EXTENDED REACHING BACK ABOVE NORMAL.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1245 PM EST SAT NOV 15 2014
GUSTY WESTERLY WINDS OFF LAKE SUPERIOR WILL CONTINUE TO LEAD TO LAKE
EFFECT CLOUDS /HIGH END MVFR/LOW END VFR/ WITH OFF AND ON SNOW
SHOWERS AND BLOWING SNOW REDUCING VIS TO AROUND 6SM AT TIMES THROUGH
EARLY EVENING.
FOR KIWD/KSAW...EXPECT VFR CONDITIONS DUE TO UNFAVORABLE WIND
DIRECTIONS FOR LAKE EFFECT. AN APPROACHING UPPER LEVEL DISTURBANCE
WILL LEAD TO INCREASING HIGH/MID CLOUDS THIS AFTERNOON-TONIGHT. KSAW
WILL BE THE CLOSEST FOR SOME SNOW SHOWERS...AND HAVE ADDED THE
POTENTIAL FROM 11-16Z AS CEILINGS FALL TO MVFR. EXPECT SW WINDS TO
INCREASE AT ALL 3 SITES SUNDAY MORNING WITH GUSTS NEARING 20KTS
PRIOR TO 18Z.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 409 AM EST SAT NOV 15 2014
UNDER A SHARP PRES GRADIENT BETWEEN HI PRES IN THE OH RIVER VALLEY
AND LO PRES OVER HUDSON BAY...PLAN ON W WINDS UP TO 20-30KTS INTO
SUN. THE WINDS WL THEN BACK TOWARD THE SW AND DIMINISH TO UP TO
25KTS IN ADVANCE OF ANOTHER STRONG DISTURBANCE MOVING THRU SCENTRAL
CANADA AND INTO NORTHERN LAKE SUPERIOR ON MON MORNING. FOLLOWING THE
PASSAGE OF THIS LO TO THE E...THE PRES GRADIENT WILL TIGHTEN AND THE
INSTABILITY WILL INCREASE AS ANOTHER SURGE OF COLD AIR FLOWS OVER
THE RELATIVELY WARM LAKE WATERS. THE RESULT WILL BE A PERIOD OF NW
GALES ON MON INTO TUE. SINCE THIS AIRMASS WILL BE SUFFICIENTLY
COLD...THERE WILL LIKELY BE SOME FREEZING SPRAY IN SOME AREAS. THE
BEST CHANCE FOR THE GALES WILL BE OVER CENTRAL LAKE SUPERIOR. AS THE
LO PRES MOVES AWAY ON TUE AND HI PRES SHIFTS E...EXPECT THE WINDS TO
BACK TO THE W AND DIMINISH TO 25 TO 30KTS. THE PASSAGE OF ANOTHER
STRONG DISTURBANCE ON WED MAY LEAD TO ANOTHER NW GALE EVENT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...JLA
AVIATION...KF
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1246 PM EST SAT NOV 15 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 416 AM EST SAT NOV 15 2014
A QUIET START TO THE SHORT TERM FORECAST THIS MORNING...AS THE AREA
IS ON THE NORTHEAST EDGE OF A HIGH CENTERED FROM THE MID/UPPER
MISSISSIPPI VALLEY TO THE OHIO RIVER VALLEY. THIS HAS LED TO A
CLEAR AND COLD NIGHT ACROSS AT LEAST HALF OF THE CWA. WHERE WINDS
HAVE DECOUPLED (GENERALLY ACROSS THE INTERIOR WEST AND NEAR THE
WISCONSIN BORDER)...TEMPERATURES HAVE FALLEN INTO THE SINGLE
DIGITS BELOW ZERO. MEANWHILE...OVER THE CENTRAL AND EAST WHERE THE
WINDS HAVE BEEN STAYING UP...TEMPERATURES HAVE BEEN IN THE UPPER
SINGLE DIGITS ABOVE ZERO TO MID TEENS.
OVER LAKE SUPERIOR AND THE KEWEENAW...COLD AIR CONTINUING TO FLOW
OVER THE RELATIVELY WARM WATERS OF LAKE SUPERIOR WAS PRODUCING
MAINLY LAKE EFFECT CLOUDS THIS PAST EVENING AND INTO THE EARLY
OVERNIGHT HOURS. BUT STARTED SEEING WEAK LAKE EFFECT BANDS
OVER EASTERN LAKE SUPERIOR ON THE CANADIAN RADAR AT MONTREAL RIVER
SHORTLY AFTER MIDNIGHT. INVERSION IS RIGHT AT 875-850MB ON 00Z
KGRB/KINL SOUNDINGS AND THE LIMITED MOISTURE ON THE NORTH EDGE OF
THE HIGH HAVE BEEN THE MAIN LIMITING FACTORS TO LAKE EFFECT SNOW
EARLY THIS MORNING. KMQT VWP HAS BEEN SHOWING THE WINDS A LITTLE
MORE OUT OF THE WEST-NORTHWEST AND CONTRIBUTING TO THE LAKE EFFECT
CLOUDS NOSING SOUTHEAST INTO BARAGA...SOUTHERN HOUGHTON...AND EVEN
FAR NORTHERN IRON COUNTY EARLY THIS MORNING. BUT AS WE HEAD INTO
THE MORNING HOURS...MODELS SHOWING THE WINDS GOING BACK TO A MORE
WESTERLY AND POTENTIALLY WEST-SOUTHWESTERLY DIRECTION AND CONFINING
THE LAKE EFFECT CLOUDS AND SNOW POTENTIAL TO THE KEWEENAW AND OFF
THE SHORELINE FROM GRAND MARAIS EASTWARD. THIS WILL ALSO BE AIDED
BY THE LAND BREEZE THAT HAS DEVELOPED ALONG THE EASTERN U.P.
SHORELINE AND WILL AID IN KEEPING THE BANDS OFFSHORE THERE. THE
COVERAGE OF THE SHOWERS IS A LITTLE BIT OF A CONCERN DUE TO THE
LIMITED MOISTURE...BUT WOULD EXPECT SOME UPTICK IN THE SNOW SHOWERS
AS 875MB TEMPERATURES FALL FROM -11C ON THE RAP ANALYSIS TO -13/-14C
BY THIS AFTERNOON. THUS...WILL CONTINUE TO SHOW POPS RAMPING UP TO
HIGH CHANCES OVER THE KEWEENAW. WITH MUCH OF THE LAKE EFFECT CLOUD
BELOW THE DGZ...WILL KEEP SNOW RATIOS ON THE LOW END FOR LAKE EFFECT
AND ONLY HAVE ACCUMULATIONS AT A DUSTING TO AN INCH IN THAT AREA.
OVER THE REST OF THE AREA...EXPECT A SUNNY START TO THE DAY WHICH
WILL ALLOW TEMPERATURES TO RISE TO THE LOW-MID 20S THIS AFTERNOON.
EXPECT MORE OF A FILTERED SUNSHINE IN THE AFTERNOON AS HIGH CLOUDS
MOVE IN AHEAD OF THE WAVE BRUSHING THE AREA LATE TONIGHT.
HEADING INTO TONIGHT...FOCUS TURNS TO THE SHORTWAVE CURRENTLY
MOVING THROUGH WYOMING. THIS WAVE WILL QUICKLY SHIFT EAST THROUGH
NEBRASKA AND SOUTH DAKOTA TODAY AND THEN LIFT NORTHEAST ACROSS
NORTHERN LAKE MICHIGAN LATE TONIGHT AND SUNDAY MORNING. EXPECT THE
HIGH CLOUDS TO THICKEN THIS EVENING AND MID CLOUDS TO MOVE IN
DURING THE LATE EVENING AND OVERNIGHT. ANOTHER SHORTWAVE (CURRENTLY
IN COLORADO) WILL LIFT NORTHEAST OUT AHEAD OF THE MAIN WAVE AND
COULD PRODUCE A FEW SHOWERS AROUND MIDNIGHT. THE BETTER/MAIN
FORCING (GENERALLY ABOVE 700MB) COMES FROM THE SECOND SHORTWAVE AND
LOOKS TO STAY SOUTHEAST OF THE AREA...BUT DO EXPECT MENOMINEE COUNTY
AND AREAS ALONG THE LAKE MICHIGAN SHORELINE TO SEE THE BEST
OPPORTUNITY FOR ACCUMULATING SNOW. CURRENT FORECAST HAS SNOWFALL
AMOUNTS UP TO AN INCH OVER SOUTHERN MENOMINEE COUNTY AND TAPERING
OFF TO A HALF INCH OR LESS SOUTH OF A LINE FROM IRON MOUNTAIN TO
MANISTIQUE. SINCE THE NORTHERN EDGE OF THE FORCING WILL BE JUST
BRUSHING THE AREA...DO EXPECT A SHARP CUTOFF TO THE PRECIPITATION TO
THE NORTHWEST AND KEEP THE SNOW CHANCES TO THE SOUTHEAST OF A LINE
FROM MARQUETTE TO WATERSMEET. AS FOR THE LAKE EFFECT OVER THE
KEWEENAW...THIS WAVE WILL BACK THE LOW LEVEL WINDS FARTHER TO THE
SOUTHWEST AND FOCUS ANY LINGERING LAKE EFFECT TO THE FAR NORTHERN
PORTIONS OF THE KEWEENAW PENINSULA. ACCUMULATIONS WILL REMAIN LIGHT
AND BELOW 2 INCHES.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 409 AM EST SAT NOV 15 2014
A HI AMPLITUDE PATTERN FEATURING A TROF OVER CENTRAL AND ERN
NAMERICA DOWNSTREAM OF A RDG ALONG THE W COAST WL DOMINATE THE WX
PATTERN THIS COMING WEEK...LEADING TO PERSISTENT BLO TO WELL BLO
NORMAL TEMPS THRU THE WEEK. THE MOST SGNFT WX CONCERN WL BE THE
IMPACT OF A POTENT SHRTWV THAT IS FCST TO DIG SEWD THRU THE UPR LKS
EARLY IN THE WEEK AND AMPLIFY THE TROF. THIS DISTURBANCE WL ALMOST
CERTAINLY BRING ANOTHER ROUND OF MODERATE TO HEAVY LES AND SOME BLSN
MAINLY TO THE NW WIND SN BELTS NEAR LK SUP ON MON INTO TUE. YET
ANOTHER DISTURBANCE DIGGING THRU THE UPR TROF MAY BRING MORE SGNFT
LES ON WED INTO THU.
SUN...ONGOING LIGHT SN OVER THE SE CWA WL END BY EARLY IN THE AFTN
AS SHRTWV OVER ERN WI AT 12Z AND ACCOMPANYING DYNAMIC FORCING/
DEEPER MSTR EXIT TO THE E THRU LOWER MI AND INTO FAR SE ONTARIO IN
THE AFTN. AXIS OF DRIER AIR/DEEP LYR QVECTOR DVGC BTWN THIS
DEPARTING SHRTWV AND ANOTHER MORE POTENT SHRTWV DIGGING SE THRU
SCENTRAL CANADA WL THEN BRING A PERIOD OF DRY WX TO THE CWA.
ALTHOUGH H85 TEMPS ARE FCST TO BE AS LO AS -12 TO -13C...THE FCST
230 DEGREE LLVL FLOW IN ADVANCE OF THE APRCHG SHRTWV WL HOLD ANY LES
MAINLY TO THE NW OF THE KEWEENAW PENINSULA AND E OF LUCE/SCHOOLCRAFT
COUNTIES. ALTHOUGH DPVA/DEEP LYR QVECTOR CNVGC IN ADVANCE OF THE
INCOMING SHRTWV ARE FCST TO INVADE THE WRN CWA LATER IN THE DAY...
THE ABSENCE OF ANY SGNFT LLVL MSTR INFLOW WL MAINTAIN DRY WX THRU
00Z MON UNDER INCRSG HI/MID CLDS.
SUN NIGHT...INCOMING SHRTWV/SFC LO ARE FCST TO DRIFT OVER NRN LK SUP
BY 12Z MON AND CAUSE 12HR H5 HGT FALLS UP TO 120M ACROSS THE UPR
LKS. AXIS OF DPVA/DEEP LYR QVECTOR CNVGC WITHIN THE COMMA TAIL OF
THIS FEATURE ARE FCST TO SWING ACROSS UPR MI. HOWEVER...POTENTIAL
FOR WIDESPREAD SN IN ADVANCE OF THE SHRTWV WL BE LIMITED BY THE
ABSENCE OF LLVL MOISTENING/PWAT UNDER 0.25 INCH/H7 SPECIFIC HUMIDITY
NO MORE THAN ABOUT 1 G/KG. STILL LOOKS LIKE THE LLVL FLOW WL NOT
BACK SUFFICIENTLY TO ALLOW ANY LK ENHANCED OFF LK MI TO IMPACT LUCE
OR SCHOOLCRAFT COUNTIES. THE BEST CHC FOR MORE WIDESPREAD/HEAVIER
SNOW WL BE OVER THE W MAINLY LATE FOLLOWING COLD FROPA AND WIND
SHIFT TO AN UPSLOPE NW DIRECTION. ARRIVAL OF H85 TEMPS AROUND -15C
WITH SHARP CYC FLOW/LINGERING DEEP MSTR UNDER THE FALLING HGTS WILL
WARRANT KEEPING LIKELY TO CATEGORICAL POPS OVER THE W. WL GO NO HIER
THAN CHC POPS ELSEWHERE...WITH THE LOWEST SCHC POPS OVER THE
SCENTRAL.
MON/MON NGT...AS THE UPR TROF DEEPENS INTO THE GREAT LKS AND A
CLOSED H5 LO FORMS...UPR MI IS FCST TO BE UNDER SHARP...CYC W
VEERING NW FLOW ON MON AND NNW-NW FLOW ON MON NGT. FCST SDNGS SHOW
DEEP MOISTURE/INSTABILITY AS H5 TEMPS DIP TOWARD -40C. GIVEN H85
TEMPS FALLING TO -16C TO -18C AND THE DEEP INSTABILITY/MOISTURE WITH
THE CYC LLVL FLOW...CATEGORICAL POPS ARE WARRANTED IN THE FAVORED SN
BELTS. GUSTY WINDS UNDER THE SHARP PRES GRADIENT/DESTABILIZATION WL
CAUSE BLSN IN ADDITIONAL TO THE HEAVIER LES. FAVORABLE OMEGA PROFILE
WITHIN THE DGZ SITUATED BTWN ABOUT 1-5K FT AGL WL ALSO ENHANCE
SN/WATER RATIOS DESPITE THE IMPACT OF THE STRONG WINDS TO FRAGMENT
THE SN FLAKES. RIGHT NOW... THE FAR W IN ONTONAGON/GOGEBIC COUNTIES
LOOKS TO PICK UP THE HEAVIEST SN ON MON NGT...WITH ADDITIONAL HEAVY
LES IMPACTING AREAS E OF MARQUETTE LATER ON MON THRU MON NGT. LATER
SHIFTS NO DOUBT WL NEED TO HOIST LES HEADLINES. THE STRONG NW WINDS
MAY ALSO CAUSE HI ENOUGH WAVES ON LK SUPERIOR TO BRING SOME MINOR
BEACH EROSION/FLOODING IN AREAS MOST EXPOSED TO THE HIER WINDS/WAVES
BEGINNING ON LATE MON. FOR NOW...WL CONTINUE TO MENTION THE SGFNT
LES POTENTIAL/BLSN AND HI WAVES IN THE HWO PRODUCT AND EHWO GRAPHICS.
TUE/TUE NGT...AS THE CLOSED LO SHIFTS INTO QUEBEC AND 12HR H5 HGT
RISES APRCH 100M ON TUE IN THE LARGER SCALE DNVA AHEAD OF TRAILING
H5 RDG AXIS...MID LVL SUBSIDENCE/DRYING/TREND TOWARD NEUTRAL OR MORE
ACYC LLVL FLOW WL TEND TO WEAKEN THE LES W TO E. STEADILY BACKING
WINDS OVER THE W THRU THE DAY AND MAINLY DURING TUE AFTN OVER THE E
WL TEND TO LIMIT THE RESIDENCE TIME OF THE HEAVIER SN BANDS AND
SHIFT THE LES TO PRIMARILY OVER THE KEWEENAW AND TO THE E OF
MUNISING BY LATE IN THE DAY. DESPITE THIS DIMINISHING TREND...SN
TOTALS ON MON THRU TUE WL LIKELY APRCH OR EXCEED A FOOT IN THE
FAVORED SN BELTS OVER THE W CENTERED IN ONTONAGON COUNTY AND E OF
MUNISING. AS THE FLOW CONTINUES TO BACK TOWARD THE SW ON TUE NGT IN
ADVANCE OF NEXT CLIPPER SHRTWV DIGGING SEWD TOWARD MN...THE MAIN
AREA OF LES SHOULD SHIFT INTO LK SUP. BUT MORE WIDESPREAD SN MAY
ARRIVE LATE AT NGT AT LEAST OVER THE W WITH THE ONSET OF MORE
VIGOROUS DYNAMIC FORCING/HGT FALLS IN THE DPVA AHEAD OF THE NEXT
SHRTWV.
WED THRU FRI...PASSAGE OF POTENT SHRTWV/VIGOROUS DYNAMIC FORCING WL
BRING THE THREAT OF A MORE WIDESPREAD SN AGAIN ON WED DESPITE RATHER
LIMITED ABSOLUTE MSTR /FCST PWAT UNDER 0.25 INCH/. MORE LES WL BE
THE RULE ON THU INTO FRI MAINLY IN THE NW WIND SN BELTS AS ANOTHER
COLD SHOT WITH H85 TEMPS AS LO AS -16 TO -18C POURS INTO THE UPR LKS
BEHIND THE DEPARTING SHRTWV. LONGER RANGE MODELS CONTINUE TO POINT
TOWARD SOME MODERATION IN THE COLD NEXT WEEKEND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1245 PM EST SAT NOV 15 2014
GUSTY WESTERLY WINDS OFF LAKE SUPERIOR WILL CONTINUE TO LEAD TO LAKE
EFFECT CLOUDS /HIGH END MVFR/LOW END VFR/ WITH OFF AND ON SNOW
SHOWERS AND BLOWING SNOW REDUCING VIS TO AROUND 6SM AT TIMES THROUGH
EARLY EVENING.
FOR KIWD/KSAW...EXPECT VFR CONDITIONS DUE TO UNFAVORABLE WIND
DIRECTIONS FOR LAKE EFFECT. AN APPROACHING UPPER LEVEL DISTURBANCE
WILL LEAD TO INCREASING HIGH/MID CLOUDS THIS AFTERNOON-TONIGHT. KSAW
WILL BE THE CLOSEST FOR SOME SNOW SHOWERS...AND HAVE ADDED THE
POTENTIAL FROM 11-16Z AS CEILINGS FALL TO MVFR. EXPECT SW WINDS TO
INCREASE AT ALL 3 SITES SUNDAY MORNING WITH GUSTS NEARING 20KTS
PRIOR TO 18Z.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 409 AM EST SAT NOV 15 2014
UNDER A SHARP PRES GRADIENT BETWEEN HI PRES IN THE OH RIVER VALLEY
AND LO PRES OVER HUDSON BAY...PLAN ON W WINDS UP TO 20-30KTS INTO
SUN. THE WINDS WL THEN BACK TOWARD THE SW AND DIMINISH TO UP TO
25KTS IN ADVANCE OF ANOTHER STRONG DISTURBANCE MOVING THRU SCENTRAL
CANADA AND INTO NORTHERN LAKE SUPERIOR ON MON MORNING. FOLLOWING THE
PASSAGE OF THIS LO TO THE E...THE PRES GRADIENT WILL TIGHTEN AND THE
INSTABILITY WILL INCREASE AS ANOTHER SURGE OF COLD AIR FLOWS OVER
THE RELATIVELY WARM LAKE WATERS. THE RESULT WILL BE A PERIOD OF NW
GALES ON MON INTO TUE. SINCE THIS AIRMASS WILL BE SUFFICIENTLY
COLD...THERE WILL LIKELY BE SOME FREEZING SPRAY IN SOME AREAS. THE
BEST CHANCE FOR THE GALES WILL BE OVER CENTRAL LAKE SUPERIOR. AS THE
LO PRES MOVES AWAY ON TUE AND HI PRES SHIFTS E...EXPECT THE WINDS TO
BACK TO THE W AND DIMINISH TO 25 TO 30KTS. THE PASSAGE OF ANOTHER
STRONG DISTURBANCE ON WED MAY LEAD TO ANOTHER NW GALE EVENT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...KC
AVIATION...KF
MARINE...KC
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
351 PM CST SAT NOV 15 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 351 PM CST SAT NOV 15 2014
STEADY LIGHT SNOW HAS ENGULFED SOUTHERN MN IN LIGHT SNOW THROUGH THE
DAY...WITH THE HEAVIEST BAND SETTING UP ALONG THE IOWA BORDER AS
EXPECTED. FOR THE REMAINDER OF THE AFTERNOON...WE`RE EXPECTING MOST
OF THE SNOW IN SOUTHERN MN TO WEAKEN AS FORCING WANES...AND THE
F-GEN MAX SLIDES SOUTH INTO IOWA...AS FRONTOLYSIS TAKES OVER ACROSS
WEST CENTRAL THROUGH SOUTHERN MN. THIS TREND IS QUITE APPARENT ON
RADAR AND HAS BEEN HANDLED WELL BY THE HRRR FOR THE LAST SEVERAL
RUNS. SO...EXPECT A LULL FOR MUCH OF THE AFTERNOON AND THE EVENING.
ANOTHER DECENT SNOW BAND WILL DEVELOP LATER TONIGHT. IT WILL CROSS
THE MN/SD BORDER AROUND 6-7 PM AND CONTINUE EASTWARD...PRODUCING
LIGHT ACCUMULATIONS ACROSS THE SOUTHERN HALF OF THE STATE AND
THROUGH WEST CENTRAL WI. FOR THE TWIN CITIES...THIS BAND WILL
PRODUCE AN ADDITIONAL 0.5"-1" MAINLY FROM 9PM THROUGH 1AM.
CURRENTLY EXPECTING THE BACK EDGE OF THIS BAND TO CROSS THE MN/WI
LINE AT ABOUT 3AM...WITH LIGHT SNOW LINGERING UNTIL 5-6AM NEAR EAU
CLAIRE.
OVERNIGHT TEMPERATURES LAST NIGHT WERE A GOOD FIVE DEGREES COLDER
THAN EXPECTED OVER THE SOLID SNOW PACK. IN COLLABORATION WITH OTHER
OFFICES...WENT SLIGHTLY COOLER ACROSS THE WEST THAN MOST OF THE
GUIDANCE...BUT THE EASTERN CWA WILL RETAIN SOMEWHAT WARMER
TEMPERATURES UNDER CONSISTENT CLOUD COVER /AND LINGERING LIGHT
PRECIP OVERNIGHT/. BY TOMORROW MORNING...WINDS WILL HAVE TURNED
WESTERLY AND WILL INCREASE THROUGH THE DAY. STRONG CAA APPARENT AT
925H ON THE BACKSIDE OF THE WAVE WILL MAKE FOR A COLD SUNDAY. 925H
TEMPS AROUND -12C ACROSS MOST OF THE REGION WILL ONLY ALLOW SURFACE
TEMPS TO MIX INTO THE UPPER TEENS.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 351 PM CST SAT NOV 15 2014
THE WEEK AHEAD REMAINS EXTREMELY COLD FOR MID NOVEMBER WITH THREE
SURGES OF ARCTIC AIR FORECAST ACROSS THE UPPER MISSISSIPPI VALLEY.
THE FIRST IS SUNDAY NIGHT/MONDAY...THE SECOND TUESDAY NIGHT/WEDNESDAY
WITH THE THIRD ON THURSDAY. LOWS/HIGHS THROUGH THE PERIOD WILL
CONTINUE TO AVERAGE SOME 20 TO 30 DEGREES BELOW NORMAL. THE TREND
TODAY WAS TO CONTINUE LOWERING TEMPERATURES OVER THE BLENDED
GUIDANCE DUE TO A MORE EXPANSIVE SNOW PACK. THE ARCTIC SURGE THAT
OCCURS SUNDAY NIGHT/MONDAY OFFERS THE BEST CHANCE FOR SNOW
SHOWERS...ESPECIALLY ACROSS CENTRAL MINNESOTA AND WEST CENTRAL
WISCONSIN...WHERE A FLUFFY INCH OR TWO COULD OCCUR. THE OTHER TWO
ARCTIC SURGES HAVE THE BETTER MOISTURE AND FORCING TO THE NORTHEAST
OF OUR FORECAST AREA RESULTING IN LESS CHANCES FOR SNOW FOR US.
THE MAIN CONCERN IN THE LONG TERM IS THE BLOWING SNOW POTENTIAL IN
THE MINNESOTA RIVER VALLEY SUNDAY NIGHT AND MONDAY. THE CONCERN
FOR BLIZZARD CONDITIONS DEVELOPING ON MONDAY HAS WANED A BIT TODAY
AS ALL OF THE DETERMINISTIC MODELS HAVE DECREASED THE SURFACE
PRESSURE GRADIENT ACROSS THE MN FORECAST AREA FROM 10 MB TO 8 MB IN
THE PAST 24 HOURS. THIS HAS LOWERED WIND SPEED FORECASTS A LITTLE
ON MONDAY FROM KRWF TO KFRM. IN ADDITION...SNOWFALL ACCUMULATION
SO FAR TODAY HAS BEEN HIGHEST IN EASTERN SOUTH DAKOTA AND FAR
SOUTHWEST MINNESOTA (OUTSIDE OF OUR FORECAST AREA) WHERE 3 TO 5
INCHES HAVE BEEN COMMON. SNOWFALL IN OUR AREA OF WEST CENTRAL
THROUGH SOUTH CENTRAL MINNESOTA HAS BEEN MORE IN THE 1 TO 3 INCH
RANGE.
BUFKIT PROFILES FROM BOTH THE NAM AND GFS SHOW THAT THE BEST LOW
LEVEL LAPSE RATES AND HIGHEST TOP OF THE CHANNEL MOMENTUM TRANSFER
DON/T OCCUR UNTIL LATE MONDAY MORNING AND AFTERNOON FROM WEST
CENTRAL THROUGH SOUTH CENTRAL MINNESOTA. ALTHOUGH AREAS OF
BLOWING SNOW WILL BEGIN ACROSS WEST CENTRAL THROUGH SOUTH CENTRAL
MINNESOTA SUNDAY NIGHT IN THE WAKE OF THE ARCTIC FRONT...THERE
ARE STILL SOME INDICATIONS THAT SUSTAINED WIND SPEEDS COULD REACH
25 MPH FROM KRWF TO KFRM MONDAY AFTERNOON WITH GUSTS HITTING 40
MPH. THIS COULD RESULT IN NEAR BLIZZARD CONDITIONS FOR A COUPLE OF
HOURS IN THESE AREAS. COMPLICATING MATTERS IS THE THREAT FOR SNOW
SHOWERS ALONG WITH THE SATURATED LOW LEVEL CONDITIONS REMAINING IN
THE DENDRITIC GROWTH ZONE.
AT THIS POINT...DIDN/T HAVE ENOUGH CONFIDENCE TO ISSUE A BLIZZARD
WATCH FOR MONDAY FROM YELLOW MEDICINE AND RENVILLE COUNTIES ON
SOUTHEAST TO MARTIN AND FARIBAULT WITH THE PRESSURE GRADIENT
WEAKENING SOME AND THE HIGHER SNOW TOTALS TODAY TO OUR WEST. THERE
IS STILL PLENTY OF TIME LATER TONIGHT TO ISSUE A WATCH IF WIND
CONDITIONS CHANGE WITH THE 00Z MODEL RUNS. OTHERWISE...A WINTER
WEATHER ADVISORY FOR BLOWING SNOW WILL LIKELY BE ISSUED ON SUNDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1145 AM CST SAT NOV 15 2014
SNOW FORECAST REMAINS ON TRACK TODAY. ALREADY A FEW INCHES OF
ACCUMULATION HAS BEEN REPORTED ALONG THE IOWA BORDER. THAT AREA
IS STILL ULTIMATELY EXPECTED TO RECEIVE THE HIGHEST
ACCUMULATIONS...IN THE 3-6" RANGE BY TOMORROW MORNING. WIDESPREAD
IFR VIS EXPECTED TO CONTINUE THROUGH EARLY AFTERNOON...AND
GUIDANCE CONTINUES TO INDICATE SNOW INTENSITIES WILL LIGHTEN UP
FOR A PERIOD THIS AFTERNOON AS THE BEST PRE FRONTAL FORCING SHIFTS
AWAY TO THE SOUTHEAST. THIS EVENING THOUGH...THE FORCING
ASSOCIATED WITH THE MAIN WAVE WILL MOVE THROUGH SOUTHERN MN AND WE
SHOULD SEE RADAR RETURNS INTENSIFY SOME. INDICATED THIS IN MANY
SITES WITH A RISE IN VSBY DURING THE LATE AFTERNOON...BUT EXPECT
THOSE TO RETURN TO IFR TONIGHT. AS FAR AS EXTENT OF THE SNOW...AXN
WILL BE LEAST AFFECTED WITH BR OR HAZE BEING MORE OF A VSBY
REDUCTION THAN PURE SNOWFALL. LOOKING FOR THE SNOW TO END
OVERNIGHT FROM WEST TO EAST...REACHING THE WI BORDER BY AROUND
09Z-10Z. AFTER THAT...A FEW HOURS OF MVFR CIGS FOLLOWED BY VFR FOR
MOST AREAS THROUGH THE MORNING ON SUNDAY. WE`LL START TO SEE SW
WINDS INCREASING AND BECOMING GUSTY LATE IN THE MORNING AND INTO
THE AFTERNOON.
KMSP...VSBY REDUCTIONS SO FAR IN LARGE PART DUE TO BR...SO NOT
MUCH ACCUMULATION DESPITE VSBYS AROUND 1SM FOR THE LAST FEW HOURS.
STILL EXPECT A BIT OF A LULL THIS AFTERNOON...WITH
RE-INTENSIFICATION LATE TONIGHT AS THE MAIN WAVE MOVES THROUGH.
STILL EXPECT AROUND AN INCH OF ACCUMULATION AT THE AIRFIELD WHEN
ITS ALL SAID AND DONE.
/OUTLOOK FOR KMSP/
MON...SLIGHT CHC -SN WITH IFR/MVFR CIGS. WINDS NW 15-20 G 25 KTS.
TUE...VFR. WINDS W 10-15 KTS.
WED...VFR. WINDS NW 10-15 KTS G 20 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR
MNZ073>076-082>085-091>093.
WI...NONE.
&&
$$
SHORT TERM...SPD
LONG TERM...RAH
AVIATION...SPD
AREA FORECAST DISCUSSION
NWS JACKSON MS
1050 AM CST SAT NOV 15 2014
.UPDATE...
FORECAST IS ON TRACK WITH ONLY ADJUSTMENTS MADE TO CLOUD COVER FOR
TODAY.
&&
.DISCUSSION...
WEAK ISENTROPIC LIFT IN 285-290K LAYER IS SUPPORTING CLOUD DECK
MOVING INTO NE LA/SE AR AND SW MS...BUT MOST RECENT HRRR GUIDANCE
INDICATES THE DECK WILL DISSIPATE BEFORE GETTING INTO CENTRAL/ERN MS
THIS AFTN WHERE HIGHER CONDENSATION PRESSURE DEFICITS AND NEUTRAL
PRESSURE ADVECTION ARE FORECAST. HAVE INCREASED THE CLOUD GRADIENT
ACROSS THE AREA KEEPING EASTERN MS SUNNY. INCREASED CLOUD COVER OVER
WESTERN PORTIONS OF THE AREA SHOULD NOT KEEP TEMPERATURES DOWN TOO
MUCH GIVEN INCREASED SE SFC FLOW. /EC/
&&
.AVIATION...VFR CONDITIONS WILL PREVAIL THROUGH THE EVENING HOURS AT
MOST AREA TERMINALS. DURING THE LATE OVERNIGHT OR EARLY SUNDAY
MORNING...CIGS WILL BEGIN TO LOWER WITH RAIN BEGINNING TO SRPEAD
ACROSS THE AREA. MVFR CEILINGS WILL BECOME LIKELY AFTER DAYBREAK...
POSSIBLY LOWERING TO IFR LATER IN THE DAY. THERE WILL ALSO BE
OCCASIONAL REDUCTIONS TO MVFR VISIBILITY IN HEAVIER RAINFALL DURING
THE DAY SUNDAY. /DL/
&&
.PREV DISCUSSION... /ISSUED 425 AM CST SAT NOV 15 2014/
SHORT TERM...GOOD RADIATIONAL COOLING NIGHT UNDERWAY ACROSS THE
AREA AS TEMPS HAVE SETTLED AS EXPECTED IN THE MID/UPPER 20S. THE
EXCEPTION HAS BEEN OVER FAR SW PORTIONS WHERE EASTWARD FRINGES OF
LOW CLOUD DECK OVER TX/LA HAVE KEPT TEMPS FROM FALLING OFF TO THEIR
FULL POTENTIAL.
CLOUD DECK OVER TX/LA IS A RESULT OF THE BEGINNINGS OF LOW LEVEL
ISENTROPIC ASCENT IN ADVANCE OF DIGGING SYSTEM OVER THE ROCKIES.
THIS DECK WILL ONLY THICKEN AND CONTINUE SPREADING EAST TODAY.
VEERING LOW LEVEL WINDS ALONG THE UPPER TX/LA COASTS TODAY WILL
INTERACT WITH COASTAL BAROCLINIC ZONE LEADING TO FRONTOGENESIS AND A
SURGING WARM FRONT NORTHWARD OVERNIGHT. AS DEEP LAYER SOUTHERLY FLOW
INCREASES...GOOD ISENTROPIC ASCENT WILL ALLOW RAIN TO BEGIN BREAKING
OUT FROM THE WEST MAINLY AFTER MIDNIGHT.
AS THE MID/UPPER LEVEL SYSTEM PULLS OUT OF THE PLAINS INTO THE LOWER
MS VALLEY SUNDAY...INCREASING DIFFLUENCE ALOFT WILL LEAD TO SURFACE
CYCLOGENESIS ALONG THE BOUNDARY OVER CENTRAL LA. AS THIS OCCURS THE
FRONTOGENETICAL FORCING WILL DRASTICALLY INCREASE...ESPECIALLY TO
THE NORTH AND EAST OF THE SURFACE LOW. WITH DEEP MOISTURE ALREADY IN
PLACE...THE ORIENTATION OF THETA-E WILL BE NEARLY UPRIGHT OVER THE
TOP OF THE BOUNDARY. THIS SHOULD EASILY LEAD TO FORCED CONVECTION
WITH THE 50+ KNOT FLOW BOUND TO THETA-E SURFACES. WHILE SOUNDINGS
FOR THE MOST PART WILL BE MOIST ADIABATIC...MODELS SOUNDINGS AND
PROFILES ARE SHOWING SOME MAUL POTENTIAL IN THE H8-H6 LAYER DUE TO
STRONG CONDENSATIONAL LATENT HEATING OVERTOP THE BOUNDARY. THIS WILL
LEAD TO SOME RATHER ROBUST UPDRAFTS WITH THE POSSIBILITIES FOR
SPORADIC THUNDER AND PERIODS OF HEAVY RAIN SUNDAY AFTERNOON AND
NIGHT. DESPITE THE RECENT DRY SPELL RAINFALL RATES MAY BE HIGH
ENOUGH IN SPOTS TO CAUSE AT LEAST MINOR ISOLATED FLOODING
WORRIES...AND THIS WILL BE ADDRESSED IN THE HWO.
NAM AND ECMWF ARE SUGGESTING THAT THE WARM SECTOR WILL SURGE NORTH
SUNDAY NIGHT WITH CAPES AOB 500 J/KG AND 35 TO 45 KNOTS OF 0-1KM
BULK SHEAR AS FAR NORTH AS A BROOKHAVEN TO QUITMAN LINE. WILL NOT
ADD ANYTHING TO THE HWO AT THE MOMENT...BUT TRENDS WILL NEED TO BE
MONITORED CLOSELY./26/
LONG TERM...MONDAY THROUGH THE END OF NEXT WEEK...BIG COLD FRONT
SHOULD BE RAPIDLY CLEARING EAST OF THE REGION MONDAY MORNING WITH
POST FRONTAL RAIN SHOWERS TAILING OFF QUICKLY FROM WEST TO EAST IN
THE MORNING AS WELL. FOR OUR REGION...CURRENT EXPECTATIONS ARE THAT
COLD AIR BEHIND THE COLD FRONT WILL NOT BE COMING IN QUICKLY ENOUGH
TO WORRY ABOUT ANY BRIEF CHANGEOVER TO FLURRIES BEFORE PRECIPITATION
ENDS (EVEN IN MY NORTHERN ZONES). CLEARING SHOULD TAKE PLACE BY
MONDAY AFTERNOON AT THE LATEST ALTHOUGH A GUSTY NORTHWEST WIND WILL
BE VERY COLD AND BITING.
EARLY SEASON MODIFYING ARCTIC AIR FUNNELING SOUTH INTO THE ARKLAMISS
LATE MONDAY MIGHT NOT MODIFY AS MUCH AS USUALLY WOULD BE THE CASE
OWING TO A LITTLE SNOWCOVER NOT TOO FAR UPSTREAM. THIS WILL LEND TO
ANOTHER STRETCH OF UNSEASONABLY COLD CONDITIONS...ALTHOUGH
FORTUNATELY WITH NOT QUITE THE STAYING POWER AS THE CURRENT STRETCH.
LOWS EARLY TUESDAY MORNING MIGHT FLIRT WITH THE UPPER TEENS IN A FEW
NORTHERN ZONES WHILE ALL OTHER AREAS SEE MINIMUMS IN THE 20S. SOME
RETURN FLOW DEVELOPING IN WESTERN ZONES BY TUESDAY NIGHT MAY LIMIT
RADIATIONAL COOLING THERE A BIT...BUT NOT ELSEWHERE WHERE LOWS WAY
DOWN IN THE 20S LOOK A SOLID BET AGAIN.
WE WILL START WARMING UP...ALBEIT NOT TERRIBLY QUICKLY...COME
WEDNESDAY AS COLD HIGH PRESSURE SHUFFLES OFF TO THE EAST AND BUILDS
SOUTH TO SOUTHWEST FLOW IN THE LOWER LEVELS. SUBTLE WAVES OF
SOUTHERN STREAM ENERGY MAKING THEIR WAY HERE BY THURSDAY AND THROUGH
THE REST OF THE WEEK WILL PROBABLY HAVE ENOUGH MOISTURE TO WORK WITH
TO GENERATE AT LEAST A FEW SHOWERS. THERE IS STILL SOME POSSIBILITY
OF A DECENT LOW SPINNING UP AND TRACKING TO OUR NORTHWEST SOMETIME
NEXT WEEKEND ALTHOUGH MODEL CONSENSUS IN THIS POTENTIALLY STORMY
DIRECTION IS NOT THE BEST. ADDING TO THE UNCERTAINTY AT THE END OF
NEXT WEEK IS THE LATEST OPERATIONAL EURO RUN SUGGESTING ANOTHER DEEP
ARCTIC INCURSION MAY PUT A SERIOUS HALT TO ANY WARMING TREND BY NEXT
SATURDAY. ANY CONSENSUS TREND TOWARD THIS OUTLYING SOLUTION WOULD OF
COURSE BE WATCHED CLOSELY. /BB/
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
421 PM CST Sat Nov 15 2014
.DISCUSSION...
Issued at 418 PM CST SAT NOV 15 2014
Tonight - Sunday:
As today`s system which generated 2-4 inches of snow over the far
northern counties exits the region our attention turns to three
secondary areas of snow. An area of snow over Nebraska is tied to a
shortwave trough moving east through western SD/NE. The trailing
band of enhanced clouds/snow is expected to drag through the CWA
overnight but only the far northwestern counties have a chance of
more than a dusting...maybe 1/2" to and inch. The expected band of
snow should diminish in intensity overnight but most areas will see
at least intermittent flurries.
The second region of snow is a result of the seeder-feeder mechanism
as noted by the broken area of enhanced mid clouds which have formed
from east central KS into west central MO. There likely is a weak
mid-level vorticity max tied to this region of cloud and the NAM h7
prog seems to hint on this. Only the short-range HRRR has picked up
on this. Could get a quick half inch of snow across the far southern
CWA during the late afternoon/early evening hours before the feature
weakens as it quickly heads east.
The third area of snow is expected to form over the CO Rockies
tonight and rapidly expand as a narrow band in response to the left
front quad of an upper level jet streak races through the Central
Rockies and into KS/OK Sunday morning. Operational models do depict
one or two vorticity lobes tracking into the region within an
overall area of ascent. At this time the northern edge of the
expected snow band could skirt across our far southern counties so
have added chance PoPs to this area.
Otherwise, until the primary upper trough passes through late on
Sunday am expecting mostly cloudy skies for most of the CWA. This
will mute the diurnal temperature range.
Monday - Tuesday:
Much below average temperatures will continue during this period
with the potential for a record low max temperature on Monday and
record setting lows Tuesday morning. Another upper trough will dig
southward Sunday night and Monday and result in falling mid/upper
level heights and enhance the flow of Arctic air southward from the
Canadian Plains to central U.S. Another surge of this air will move
in during this period. Steep lapse rates below 750mb and a moist
layer residing within the boundary layer suggests a good chance for
instability snow showers or flurries Monday afternoon.
Wednesday - Saturday:
This should be a dry period with a continuation of the unseasonably
cold regime. Cyclonic/northwest flow aloft will continue featuring
the potential for weak embedded shortwaves to pass through. However,
the airmass will be quite dry so it should remain dry. A slight
moderation in temperatures are expected but they will remain about
15 degrees below average.
A particularly cold air mass will swing into the Central Plains
Monday into Tuesday. This will result in the coldest temperatures we
have seen this fall with both Monday`s high temperatures and Tuesday
morning`s low temperatures possibly setting new records. Here is a
quick look at just some of those threatened temperature records.
&&
.AVIATION...(For the 18Z TAFS through 18Z Sunday Afternoon)
Issued at 1145 AM CST SAT NOV 15 2014
Band of heavier snow will affect far northwest and north central MO
this afternoon with MVFR visibilities and cigs. The higher
accumulating snows will miss the Kansas City terminals and graze KSTJ.
For the terminals, after the initial light snow with MVFR
visibilities/cigs moves through very early this afternoon expect
cigs to improve into the low end VFR category for the rest of this
afternoon and evening. Intermittent light snow or flurries expected through
the night with only minor additional accumulations. Weak frontal
passage from northwest to southeast starting in the pre-dawn hours.
Could see several hours of MVFR cigs after frontal passage with these
clouds clearing to the southeast by mid morning.
&&
.CLIMATE...
Issued at 418 PM CST SAT NOV 15 2014
Monday
November 17th Current Record Low Forecast High Monday
Record Low Highs High Afternoon
--------------------------------------------------------------------
Kansas City 24 in 1891 22
St. Joseph 26 in 1951 22
Tuesday
November 18th Current Record Low Forecast Low Tuesday
Record Lows Morning
--------------------------------------------------------------------
Kansas City 14 in 1903 7
St. Joseph 16 in 1989 5
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
MO...WINTER WEATHER ADVISORY until Midnight CST tonight FOR
MOZ001>003-011.
&&
$$
UPDATE...MJ
DISCUSSION...MJ
AVIATION...MJ
CLIMATE...Cutter
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
351 PM CST Sat Nov 15 2014
.SHORT TERM: (Through Late Tonight)
Issued at 347 PM CST Sat Nov 15 2014
Shortwave exiting the eastern Plains into the Mississippi Valley is
producing a little bit of light snow and flurry activity across the
CWFA today. Looks like the best snowfall has moved north of our
CWFA across extreme northeast Missouri and southeast Iowa into west
central Illinois. The broad scale mid level lift associated with
the shortwave is lifting quickly northeast according to the RAP and
NAM. Will likely see a little bit of lingering snowfall up there
this evening, but any accumulations this evening should be well
under an inch.
Further south, HRRR and RAP have been very insistent that there will
be a frontogenetical band of snow this evening somewhere between
I-44 and I-70. The band will move northeast affecting parts of the
STL metro area with some light snow. Simulated reflectivity off the
4km NCEP and NSSL WRF models also show this, and the operational NAM
and GFS bear this out with a few hundredths of QPF. Latest radar
mosaic shows a band of snow developing west central Missouri
now...so this looks likely to happen. Have a band of likely PoPs
this evening in to account for this snow, stretching across central
Missouri into southwest Illinois to account for this.
Carney
.LONG TERM: (Sunday through Next Saturday)
Issued at 347 PM CST Sat Nov 15 2014
(Sunday thru Tuesday)
This period will continue to feature much below normal temps and
another shot at accumulating snow. Models have come into better
agreement with the system for Sunday/Sunday night. All guidance has
shifted the forcing and subsequently the precip shield further
north. Timing should be similar to today`s event. Precip is
expected to begin across cntrl and SE MO around noon and then spread
east thru the rest of the CWA during the aftn and then clear from W
to E during the evng and be but a memory by midnight. The main
p-type should be snow with temps aloft plenty cold enough to support
ice crystal formation but...air temps above freezing at the
beginning of the event may cause a rain/snow mix at the onset of the
precip. I think the mix won`t last long as temps should wet bulb
shortly after the precip begins. This will likely lead to a
non-diurnal temp trend as temps fall across the sthrn CWA as the
precip progresses east. Accum rates may be limited early on in the
event for a variety of reasons beyond the warm air temps
including...ground temps will likely be above freezing, snowfall
rates may not be high enough and the aftn sun...even with the
diminished angle...will have an effect. Event total snowfall amounts
should be 1-2 inches along and south of I70. There may be a band of
slightly enhanced snowfall along the I44 corridor that may reach
upwards of 3 inches but not confident on band placement to include
in the fcst attm. The system quickly lifts east after midnight.
Monday looks like a raw day with potentially steady or slowly
falling temps and a stiff NW wind as a 1030mb sfc high builds in.
850 temps fall from the negative single digits at 6Z Monday to the
negative mid teens to near -20 by Monday evening. There is also an
impressive short wave dropping down in the NW flow on Monday that
should instigate at least occnl flurries with the possibility of
actual snow showers...as was the case this past Thursday. Models
hint at patchy QPF which would equate to a few tenths of an inch of
snow...but will let later shifts asses that threat as it is still 2
days away. Tuesday should be the last truly cold day as the sfc
ridge passes to the south.
(Tuesday night thru Friday)
The upper flow flattens thru the end of the week which will allow
for a moderating trend. Winds will swing around to the south on the
backside of the high Tuesday night. 850 temps near 0 and a Srly wind
will boost temps to the upper 30s north to the upper 40s south
on Wednesday. The next short waves pushes a cold front thru late in
the day on Wednesday causing temps on Thursday and Friday to be a
touch cooler. This front appears to be dry at this time. Models
guidance diverges after this feature with the GFS building a strong
sfc ridge into the Midwest for the end of the week while the ECMWF
has another short wave and an attendant weak sfc low that tracks
across sthrn MO/IL Thursday/Thursday night.
Both models suggest another storm system for either the wknd and/or
early next week as the next main short wave approaches in the mean
flow.
2%
&&
.AVIATION: (For the 18z TAFs through 18z Sunday Afternoon)
Issued at 1204 PM CST Sat Nov 15 2014
Upper level disturbance moving out of eastern Kansas into Missouri
is producing snow over northern/northwestern portions of the
state. Some trailing precipitation to the south will overspread
the area this afternoon, but due to very dry low levels, it will
take a while to make it to the ground. Think best chances of snow
this afternoon will be across northern portions of the CWFA in
northeast Missouri and west central Illinois, tho some light snow
is also likely further south. Another band of snow will likely
form between I-44 and I-70 across Missouri and move northeast this
evening impacting east central Missouri into southwest Illinois.
VFR flight conditions should prevail outside of some of the
heavier snow showers this afternoon and the bands across northern
Missouri this afternoon, and the second band in east central
Missouri and southwest Illinois. Flight conditions could drop to
IFR in these areas, but MVFR vsbys/ceilings are most likely. After
the southern band moves out this evening, VFR flight conditions
are expected through Sunday morning.
Specifics for KSTL:
Expect VFR flight conditions to prevail for most of the afternoon.
Precipitation west of the terminal associated with an upper level
disturbance will most likely evaporate before hitting the ground,
but another band of snow is expected to develop between I-44 and
I-70 across Missouri and move northeast this evening impacting east
central Missouri into southwest Illinois. The exact position of
the band will determine how heavy the snow will get at Lambert,
but the band should be fairly narrow and short-lived. While there
is a chance for IFR conditions with the band, think the most
likely impact will be MVFR visibility for a short period this
evening. VFR flight conditions are expected to prevail after the
band clears the region by mid-evening. There is another chance of
snow Sunday afternoon...but have left mention out for now to focus
on the short-range forecast.
Carney
&&
.CLIMATE:
Issued at 748 PM CST Thu Nov 13 2014
The following are record low maximums and record low minimums for
each of the next 5 days, which corresponds to the expected length
of the current cold spell and record snowfall for St. Louis and
Columbia for Saturday and Sunday when the area is expecting the
first widespread accumulating snowfall of the season.
Date: 11/15 11/16 11/17 11/18
St. Louis
Low High: 29/1940 29/1997 17/1880 25/1880
Low: 11/1940 13/1959 6/1959 14/1932
Snowfall: 0.1/1997 1.0/1951
Columbia
Low High: 28/1940 30/1932 23/1959 27/1903
Low: 6/1940 8/1959 4/1959 8/1891
Snowfall: 4.8/1932 0.1/1989
Quincy
Low High: 29/1940 28/1997 19/1959 24/1903
Low: 7/1940 4/1959 3/1959 7/1903
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
337 PM CST SAT NOV 15 2014
.SHORT TERM...(TONIGHT THROUGH TUESDAY)
ISSUED AT 331 PM CST SAT NOV 15 2014
ENDING SNOW TONIGHT...THEN COLD TEMPERATURES THE NEXT FEW DAYS...ARE
THE PRIMARY FORECAST CONCERNS.
FIRST ROUND OF SNOW TIED TO SOUTHERN SHORTWAVE/WARM ADVECTION
PATTERN MOVED EAST/NORTHEAST OF THE CWA BY EARLY AFTERNOON. THIS
AREA DROPPED AN INCH OR TWO OF SNOW ACROSS THE SOUTHERN HALF OF
THE CWA. ANOTHER AREA OF SNOW WAS ENTERED THE WESTERN PART OF
NORTHEAST NEBRASKA EARLY IN THE AFTERNOON. THIS WAS TIED TO
STRONGER UPPER LOW/TROUGH SWINGING THROUGH WESTERN SOUTH DAKOTA.
75KT MID LEVEL JET WAS ROUNDING BASE OF THIS FEATURE...INCREASING
LIFT IN NORTHEAST WHERE SECOND ROUND OF SNOW WAS FALLING THIS
AFTERNOON. CHARACTER OF RADAR RETURNS SUGGEST THIS AREA WILL
PRODUCE LIGHT SNOW FOR THE MOST PART...WITH A FEW ROUNDS OF
MODERATE SNOW FROM TIME TO TIME. PROGRESSIVE NATURE ALSO SUGGESTS
MESOSCALE MODEL FORECASTS FROM HRRR AND RAP IN SHOWING SNOW
AFFECTING MAINLY THE NORTHERN HALF OF THE CWA AND WINDING DOWN BY
MIDNIGHT STILL LOOKS GOOD. ADDITIONAL AMOUNTS OF 1 TO 2 INCHES ARE
POSSIBLE IN THE NORTHERN TWO-THIRDS OF THE CWA TAPERING TO LESS
THAN AN INCH TOWARD THE KANSAS BORDER.
BACK EDGE OF SNOW WILL ALSO COINCIDE WITH COLD FRONT SWEEPING ACROSS
THE PLAINS. FRONT WILL PASS NORFOLK BY 9 PM AND BE APPROACHING OMAHA
BY MIDNIGHT. GUSTY NORTHWEST WINDS OF 15 TO 25 MPH SHOULD
FOLLOW...CAUSING A LITTLE BLOWING AND DRIFTING OF SNOW OVERNIGHT
BEFORE WINDS BEGIN TO SUBSIDE SOME ON SUNDAY. CLEARING SKIES AFTER
MIDNIGHT...COLD AIRMASS AND FRESH SNOW COVER WILL LEAD TO COLD
TEMPERATURES BY MORNING...WITH WINDS ONLY THING KEEPING LOWS FROM
BOTTOMING OUT. SINGLE DIGITS ARE FORECAST MOST EVERYWHERE.
SUNDAY WILL BRING SUNSHINE AND SOUTHWEST FLOW AHEAD OF A REINFORCING
COLD FRONT SLATED TO ARRIVE INTO NORTHEAST NEBRASKA IN THE
AFTERNOON...THEN THROUGH THE REST OF THE AREA DURING THE EVENING.
SNOW COVER WILL KEEP TEMPS FROM REACHING MAXIMUM POTENTIAL SUNDAY
AFTERNOON...WITH LOWER 20S EXPECTED MOST AREAS. MORE GUSTY NORTHWEST
WINDS WILL ACCOMPANY COLD FRONT AND SHOULD CONTINUE ALL NIGHT.
EXTREMELY COLD AIRMASS FOLLOWS THE FRONT WITH MODELS SHOWING -20
850 TEMPERATURES INTO OUR NORTHERN CWA BY 12Z MONDAY. THIS WILL
TRANSLATE TO LOWS AGAIN IN THE SINGLE DIGITS WITH HIGHS REBOUNDING
ONLY BACK INTO THE TEENS MONDAY AFTERNOON. WIND CHILLS MONDAY
MORNING WILL LIKELY FALL TO 15 BELOW OR COLDER FOR MUCH OF THE
NORTHERN HALF OF THE CWA.
DECREASING WINDS AND CLEARING SKIES SUGGEST TUESDAY MORNING MAY BE
THE COLDEST OF THIS RECENT COLD SPELL. LOWS NEAR ZERO ARE LIKELY
ACROSS ALL OF EASTERN NEBRASKA AND SOUTHWEST IOWA...WITH SUB-ZERO
TEMPS NEARLY A CERTAINTY IN OUR NORTH. SOUTHWEST FLOW RETURNS FOR
TUESDAY...HELPING TO WARM TEMPS BACK INTO THE MID 20S IN THE
AFTERNOON.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 331 PM CST SAT NOV 15 2014
SLOWLY MODERATING TEMPERATURES APPEAR TO BE THE MAIN STORY IN THE
LONGER TERM PERIOD.
ANOTHER SHORTWAVE IS SHOWN BY GFS/ECMWF SLAMMING THROUGH MINNESOTA
AND IOWA TUESDAY NIGHT...BRINGING ANOTHER SHOT OF COLDER AIR INTO
THE PLAINS THROUGH WEDNESDAY. HOWEVER THIS WILL NOT BE NEARLY AS
COLD AS EARLIER IN THE WEEK WITH HIGHS WEDNESDAY INTO THE 20S AND
LOWER 30S. MID LEVEL HEIGHTS BEGIN A SLOW RISE FOR THE REST OF THE
WEEK AS FLOW BECOMES MORE ZONAL BEHIND TUESDAY NIGHT SHORTWAVE.
ANOTHER SHOT OF SOMEWHAT COOLER AIR IS EXPECTED THURSDAY...BUT THAT
LOOKS SHORT-LIVED. HAVE HIGHS REBOUNDING BACK INTO THE 30S FRIDAY
AND SATURDAY. OTHERWISE A DRY FORECAST REMAINS INTACT.
&&
.AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1209 PM CST SAT NOV 15 2014
MAIN BAND OF MODERATE TO HEAVY SNOW ABOUT TO MOVE ACROSS KOMA AT
THE START OF THE PERIOD. ONCE THIS AREA MOVES TO THE EAST EXPECT
PRIMARILY MVFR CIGS AND VSBY AT ALL THREE SITES WITH OCCASIONAL
IFR CONDITIONS THROUGH ABOUT 02Z IN ADVANCE AND JUST BEHIND THE
COLD FRONT MOVING INTO CENTRAL NEBRASKA AT 18Z. VFR CONDITIONS ARE
EXPECTED TO DEVELOP AFTER 12Z AS FRONT MOVES FURTHER EAST AND HIGH
PRESSURE BUILDS INTO THE AREA AHEAD OF NEXT COLD FRONT. THIS SECOND
COLD FRONT WILL BE MOVING INTO THE AREA JUST AFTER THE END OF
THE FORECAST PERIOD.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR NEZ011-
012-015>018-030>034-042>045-050>053-065>068-078.
IA...WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR IAZ043-
055-056-069-079-080-090-091.
&&
$$
SHORT TERM...DERGAN
LONG TERM...DERGAN
AVIATION...FOBERT
AREA FORECAST DISCUSSION
NWS RALEIGH NC
334 PM EST SAT NOV 15 2014
.SYNOPSIS...HIGH PRESSURE CENTERED OVER THE REGION THIS AFTERNOON
WILL GRADUALLY SHIFT OFFSHORE TONIGHT AND SUNDAY. A DEVELOPING LOW
PRESSURE SYSTEM ATTENDANT AN AMPLIFYING UPPER LEVEL TROUGH WILL
INTENSIFY IN VICINITY OF THE LOUISIANA GULF COAST ON SUNDAY...THEN
TRACK NORTHEAST ALONG THE SPINE OF THE APPALACHIANS SUNDAY NIGHT
INTO MONDAY. AN ASSOCIATED COLD FRONT WILL SWEEP EASTWARD THROUGH
THE CAROLINAS MONDAY AFTERNOON AND EVENING.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 300 PM SATURDAY...
TODAY: MODIFIED ARCTIC HIGH PRESSURE CENTERED OVER THE REGION WILL
ENSURE THAT DRY CONDITIONS AND LIGHT/VARIABLE WINDS PREVAIL THROUGH
TONIGHT. THE LOW-LEVEL CORE OF THE MODIFIED ARCTIC AIRMASS WAS
ANALYZED DIRECTLY OVER CENTRAL NC AND EASTERN VA THIS AFTERNOON
(18Z)...CHARACTERIZED BY 925 MB TEMPS IN VICINITY OF -2C. PWAT
VALUES BOTTOMED OUT AT A `FINGER-CRACKING` 0.14 INCHES ON THE GSO
RAOB 00Z YESTERDAY. 18Z MESOANALYSIS AND RAP DATA INDICATE MID/UPPER
LEVEL MOISTURE HAS STEADILY INCREASED SINCE 00Z...THOUGH LITTLE
EVIDENCE THEREOF (I.E. CIRRUS) CAN BE IDENTIFIED VIA SATELLITE
IMAGERY. GIVEN CLEAR SKIES AND MARGINAL LOW-LEVEL MODIFICATION IN
COMPARISON TO YESTERDAY...EXPECT HIGHS SIMILAR ALBEIT SLIGHTLY WARMER
THAN YESTERDAY...IN THE LOWER/MID 40S.
TONIGHT: MODIFIED ARCTIC HIGH PRESSURE CENTERED OVER THE MID-
ATLANTIC THIS EVENING WILL SHIFT OFFSHORE THE MID-ATLANTIC COAST
LATE TONIGHT...IN ADVANCE OF SHORTWAVE ENERGY TRACKING EASTWARD FROM
THE DAKOTAS TO THE UPPER GREAT LAKES. MEANWHILE...UPSTREAM PRECIP IS
EXPECTED TO BLOSSOM ACROSS THE LOWER MS RIVER VALLEY AFTER MIDNIGHT
AS SHORTWAVE ENERGY DIGS SSE FROM THE PACIFIC NW TO THE COLORADO
FRONT RANGE. ASIDE FROM AN INCREASING LIKELIHOOD OF CIRRUS ADVECTING
INTO THE REGION VIA WSW FLOW ALOFT...FAVORABLE RADIATIONAL COOLING
CONDITIONS WILL OTHERWISE PREVAIL. DUE TO AIRMASS MODIFICATION
ASSOC/W THE ONSET OF A LIGHT SOUTHERLY/SW RETURN FLOW...ANTICIPATE
LOWS A FEW DEGREES WARMER THAN THIS MORNING...IN THE MID TO UPPER
20S. -VINCENT
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 315 PM SATURDAY...
SUN/SUN NIGHT: CHALLENGING TEMPERATURE AND PRECIP FORECAST. THE
ONSET OF WARM ADVECTION...I.E. SOUTHERLY RETURN FLOW EMANATING FROM
THE ATLANTIC /GULF STREAM/...WILL RESULT IN INCREASING CLOUD COVER
AND THE DEVELOPMENT OF A HYBRID OR IN-SITU COLD AIR DAMMING WEDGE.
ELEVATED SHOWER ACTIVITY WILL BE POSSIBLE SUNDAY EVE/NIGHT AS LOW-
LEVEL WARM ADVECTION FURTHER STRENGTHENS ATOP THE SHALLOW COLD AIR
DAMMING WEDGE IN ADVANCE OF A WARM FRONT LIFTING NORTHWARD THROUGH
CENTRAL/EASTERN NC. GIVEN THE EXPECTATION OF BROKEN/OVERCAST
CEILINGS AT LOWER (STRATUS) AND UPPER (CIRRUS) LEVELS...EVAP COOLING
ASSOCIATED WITH AN INITIALLY DRY SURFACE AIRMASS ALONG WITH VIRGA
AND AN INCREASING POTENTIAL FOR ELEVATED SHOWERS...EXPECT CHILLY
AFTERNOON TEMPERATURES RANGING FROM THE UPPER 30S TO MID 40S (NW) TO
MID 40S/LOWER 50S IN THE SE COASTAL PLAIN. EXPECT TEMPERATURES TO
RISE OVERNIGHT FROM SOUTH TO NORTH AS THE LOW-LEVELS SATURATE AND A
WARM FRONT LIFTS NORTHWARD THROUGH CENTRAL/EASTERN NC. TEMPS IN THE
TRIAD MAY HOLD STEADY FOR MUCH OF THE NIGHT...THOUGH A SLOW RISE
STILL APPEARS LIKELY BY SUNRISE. -VINCENT
MONDAY THROUGH MONDAY NIGHT...UPPER TROF ROTATING ACROSS THE UPPER
MIDWEST INTO THE GREAT LAKES WILL PUSH THE STRONG COLD FRONT EAST
ACROSS THE AREA. AMPLITUDE OF THE SYSTEM WILL PROVIDE A DEEP
SOUTHWEST TAP INTO THE GULF AHEAD OF THE FRONT...WITH A PLUME OF
PRECIPITABLE WATER OF 1.5 INCHES EDGING INTO CENTRAL AND EASTERN
NORTH CAROLINA BY AFTERNOON COURTESY OF A 50+ KNOT LOW LEVEL JET AT
H850 STRAIGHT OFF THE GULF. TIMING DISCREPANCIES ARE MINOR
CONCERNING SENSIBLE WEATHER AND WILL MAINTAIN OUR ONGOING
CATEGORICAL POPS IN THE WEST IN THE MORNING PROGRESSING EAST TO THE
I-95 CORRIDOR DURING THE AFTERNOON. SOUTHERLY WINDS AT 10-15 MPH
GUSTING TO 20 WILL VEER SOUTHWEST TO WEST DURING THE AFTERNOON AND
NORTHWEST OVERNIGHT.
HIGHS IN THE EAST WILL HAVE AMPLE TIME TO REACH NEAR 70 PRIOR TO THE
FRONT WHICH PROGS TO A COUPLE OF HUNDRED JOULES OF CAPE. VERTICAL
ALIGNMENT OF THE DEPARTING 150KT UPPER JETS DIFFLUENCE AND
PERTURBATIONS IN THE MID LEVEL FLOW WOULD AID CONVECTIVE DEVELOPMENT
AND WILL EXPAND MENTION OF THUNDER WEST ACROSS THE TRIANGLE AND
SANDHILLS. TEMPERATURES IN THE NORTHWEST ARE A LITTLE MORE UNCERTAIN
DUE TO POTENTIAL FOR IN-SITU LINGERING COOL AIR DUE TO EVAPORATIVE
COOLING SUNDAY NIGHT. THIS WOULD BLOCK THE TRANSITION TO A MORE
PLEASANT SOUTHERLY SURFACE FLOW AND HIGHS WOULD STRUGGLE TO REACH
MID 50S.
THE FRONT WILL BE MOVING SMARTLY ALONG...WITH SHOWERS ENDING AND
CLEARING COMMENCING TOWARDS SUNSET IN THE WEST TO AROUND MIDNIGHT IN
THE EAST. TEMPS WILL PLUMMET AS COLD AIR RUSHES IN AND THICKNESSES
CRASH OVERNIGHT...MONDAY NIGHTS MINS LOOK TO FALL BELOW FREEZING
OVER THE PIEDMONT...WITH MID 30S IN THE EASTERN THIRD OF THE AREA.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 300 PM SATURDAY...
A COLD STRETCH IS ON TAP BEHIND THE FRONT AS POLAR AIR PAYS THE AREA
A VISIT TUESDAY AND WEDNESDAY. THE INITIAL SURGE WILL BE BRISK AND
RAW ON TUESDAY...FEATURING NORTHWEST WIND GUSTING TO 20 MPH AND
THICKNESSES BARELY INDICATIVE OF MID 30S OVER THE NORTHWEST TO LOWER
40S SOUTHEAST. SURFACE HIGH SETTLING OVER THE AREA AND LOOSENING
PRESSURE GRADIENT WILL BE IDEAL FOR RADIATIONAL COOLING AND MINS
WILL BE COLDEST WEDNESDAY MORNING...WITH MOST AREAS WITHIN A COUPLE
OF DEGREES OF 20. SLIGHT DEAMPLIFICATION OF THE TROF AND ANOTHER DAY
OF STRONG INSOLATION WILL PROVIDE SOME VERY MODEST WARMING ON
WEDNESDAY...WITH HIGHS FROM 40 TO 45.
FORECAST FOR LATE WEEK IS MORE UNCERTAIN AS THERE IS MODEL
UNCERTAINTY IN THE SUBSEQUENT EVOLUTION OF THE UPPER TROF AND
STRONGER INDICATIONS OF A SURFACE SYSTEM DEVELOPING AND SKIRTING THE
AREA ON FRIDAY IN THE ECMWF. REGARDLESS...TEMPS WILL MODERATE IN THE
THURSDAY THROUGH SATURDAY TIME FRAME AS THE TROF DEAMPLIFIES AND
HIGHS EACH DAY LOOK TO BE IN THE LOW TO MID 50S...MAYBE A LITTLE
WARMER ON THE WEEKEND AS WE SIT UNDER A STRONG HIGH AND TRANSITION
BRIEFLY TO A LOW AMPLITUDE UPPER RIDGE. AT THIS POINT AM THINKING
ONLY HIGH CLOUDINESS IN THE FASTER FLATTER FLOW AND WILL HAVE ONLY
SLIGHT CHANCE POPS FOR THE FRIDAY NIGHT INTO SATURDAY TIME FRAME.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
AS OF 100 PM SATURDAY...
24-HR TAF PERIOD: VFR CONDITIONS AND LIGHT WINDS WILL PREVAIL
THROUGH TONIGHT AT ALL TERMINALS AS HIGH PRESSURE CENTERED OVER THE
REGION GRADUALLY BEGINS TO SHIFT OFFSHORE. SUB-VFR CEILINGS WILL BE
POSSIBLE AT ALL TERMINALS BY THE END OF THE TAF PERIOD (12-18Z SUN)
IN ASSOCIATION WITH THE ONSET OF WARM ADVECTION AS THE SFC HIGH
MOVES FURTHER OFFSHORE AND A WARM/MOIST AIRMASS ADVECTS INTO THE
CAROLINAS FROM THE ATLANTIC.
LOOKING AHEAD: AN EXTENDED PERIOD OF ADVERSE AVIATION CONDITIONS IS
EXPECTED SUNDAY AFT/EVE INTO SUN NIGHT IN ASSOC/W WARM ADVECTION
ATOP A SHALLOW COLD AIR DAMMING WEDGE IN ADVANCE OF A POTENT COLD
FRONT APPROACHING THE MOUNTAINS FROM THE WEST. THE COLD FRONT WILL
SWEEP EASTWARD THROUGH THE REGION LATE MONDAY AFTERNOON. BREEZY
NORTHWEST WINDS WILL OCCUR IN THE WAKE OF THE FRONT MONDAY NIGHT
INTO TUESDAY AS ANOTHER ARCTIC HIGH BUILDS INTO THE REGION FROM THE
WEST. -VINCENT
&&
THE FOLLOWING ARE RECORD TEMPERATURES THAT WILL BE CHALLENGED
THROUGH THE FORECAST PERIOD:
RECORD LOW:
GSO RDU FAY
WED 11/19 - 20 IN 1951 21 IN 1903 21 IN 1959
THU 11/20 - 12 IN 1951 19 IN 1951 20 IN 1951
RECORD LOW MAX:
GSO RDU FAY
TUE 11/18 - 37 IN 1924 35 IN 1924 46 IN 2008
WED 11/19 - 34 IN 1951 36 IN 1951 41 IN 2000
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...VINCENT
SHORT TERM...VINCENT
LONG TERM...MONEYPENNY
AVIATION...VINCENT
CLIMATE...MWS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1219 PM CST SAT NOV 15 2014
.UPDATE...
ISSUED AT 1220 PM CST SAT NOV 15 2014
CONTINUED TO EXPAND ISOLATED FLURRIES SOUTHEAST AS THE STRATUS
DECK WITH EMBEDDED FLURRIES CONTINUES TO DRIFT SOUTH OVER WESTERN
AND CENTRAL NORTH DAKOTA THIS AFTERNOON.
FOCUS THEN SHIFTS TO WINDS AND BLOWING SNOW POTENTIAL SUNDAY. WILL
CONTINUE TO COLLABORATE WITH SURROUNDING OFFICES TO ENSURE
CONSISTENT HEADLINES. WILL HAVE HEADLINE DECISIONS REACHED BY THE
MID-AFTERNOON UPDATE TIME.
UPDATE ISSUED AT 839 AM CST SAT NOV 15 2014
UPDATED THE FORECAST TO CANCEL THE WIND CHILL ADVISORY FOR WEST
CENTRAL AND NORTHWESTERN NORTH DAKOTA THIS MORNING.
11-3.9 MICRON SATELLITE IMAGERY SHOWS A STRATUS DECK BEGINNING TO
DRIFT SOUTH ACROSS NORTHWESTERN NORTH DAKOTA. ISOLATED FLURRIES
HAVE BEEN REPORTED UNDER THIS STATUS DECK. AS A RESULT...ADDED
ISOLATED FLURRIES TO THE FORECAST NORTHWEST THIS MORNING. THE
STRATUS SHOULD BEGIN TO BREAK UP SOMEWHAT BY THIS AFTERNOON. THE
REMAINING WEATHER ELEMENTS ARE IN GOOD SHAPE. THE UPDATED PRODUCTS
HAVE BEEN SENT.
UPDATE ISSUED AT 653 AM CST SAT NOV 15 2014
NO SIGNIFICANT CHANGES WITH THIS FORECAST UPDATE OTHER THAN TO
BLEND TO OBSERVED TRENDS THROUGH 12 UTC. WILL LEAVE THE WIND CHILL
ADVISORY IN PLACE AS BORDERLINE ADVISORY CRITERIA VALUES NEAR -25
WILL CONTINUE EARLY THIS MORNING.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 406 AM CST SAT NOV 15 2014
MAIN HIGHLIGHT THIS MORNING IS A WIND CHILL ADVISORY FOR PORTIONS OF
THE FAR WEST. COLDER AIR COMING IN FROM THE WEST AND BRISK WINDS
WILL DOMINATE THROUGH MID MORNING. A POTENT SHORTWAVE AND ASSOCIATED
COLD FRONT SHIFTING SOUTH FROM CENTRAL CANADA WILL BEGIN TO IMPACT
WESTERN/NORTHERN NORTH DAKOTA LATE SATURDAY NIGHT THEN SPREAD SOUTH
SUNDAY MORNING.
THE LATEST WATER VAPOR IMAGERY SHOWS AN ELONGATED UPPER TROUGH
FROM HUDSON BAY SOUTHWEST INTO MONTANA. AHEAD OF THE TROUGH...A
SHORTWAVE WAS SEEN ALONG THE WYOMING/MONTANA BORDER MOVING EAST TO
SOUTHEAST WITH TIME...AS THE SURFACE LOW REMAINS FARTHER SOUTH.
LIGHT SNOW ASSOCIATED WITH THIS SYSTEM EXTENDED ACROSS CENTRAL AND
SOUTHERN SOUTH DAKOTA AND IS MOVING EAST. FARTHER UPSTREAM...AN
AREA OF STRATUS OVER SOUTHERN SASKATCHEWAN PER LATEST FOG/STRATUS
LOOP CONTINUES A SOUTHEAST MOVEMENT. THE HRRR AND RAP13 SHIFT THIS
INTO NORTHWEST AND NORTH CENTRAL NORTH DAKOTA BETWEEN 12Z-21Z
TODAY. CONCUR WITH THIS AND ADJUSTED SKY GRIDS ACCORDINGLY.
ELSEWHERE ISOLATED FLURRIES WITH POCKETS OF STRATUS CONTINUE EARLY
THIS MORNING IN THE FAR SOUTHWEST...ALONG AND SOUTH OF LAKE
SAKAKAWEA...AND IN THE SOUTHERN JAMES RIVER VALLEY. ANOTHER VERY
COLD DAY AHEAD WITH HIGHS IN THE SINGLE DIGITS ABOVE ZERO IN THE
WEST AND SOUTHWEST...TO LOWER/MIDDLE TEENS ELSEWHERE. BRISK
NORTHWEST WINDS THIS AFTERNOON 10 TO 25 MPH.
FOR TONIGHT...ATTENTION TURNS TO A STRONG SHORTWAVE TROUGH AND
ASSOCIATED SHARP COLD FRONT HEADING DUE SOUTH FROM THE NORTHWEST
TERRITORIES. THE COLD FRONT WILL PASS THROUGH NORTHWEST AND NORTH
CENTRAL AFTER MIDNIGHT WITH INCREASING WINDS TOWARD AND SHORTLY
AFTER DAYBREAK ON SUNDAY.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 406 AM CST SAT NOV 15 2014
BLOWING SNOW POTENTIAL ON SUNDAY HIGHLIGHTS THE EXTENDED FORECAST.
THE 00 UTC GUIDANCE SUITE CONTINUES THE TREND OVER THE PAST
SEVERAL DAYS OF A REINFORCING COLD FRONT TO PROPAGATE ACROSS
WESTERN AND CENTRAL NORTH DAKOTA SUNDAY MORNING IN ASSOCIATION
WITH ITS PARENT CLIPPER SYSTEM ACROSS EASTERN MANITOBA INTO
WESTERN ONTARIO. STRONG NORTHWEST WINDS INTERACTING WITH THE
SNOWFALL FROM LAST WEEKEND PRESENTS A BLOWING SNOW THREAT. THE
CHALLENGE IS IF BLIZZARD CRITERIA WILL BE MET ACROSS THE SOUTHWEST
WHERE THE MOST SNOW WAS RECEIVED. THE SNOW HAS BEEN ON THE GROUND
FOR A WEEK...HOWEVER...IT IS UNCRUSTED AND HAS NOT BEEN
SIGNIFICANTLY COMPACTED. THAT SAID....BEING THE FIRST SNOWFALL OF
THE SEASON...SOME OF THE SNOW MAY BE ADVERSE TO BEING LOFTED FROM
BEING TRAPPED IN THE GRASSES. THUS...WILL FORGO A BLIZZARD WATCH
FOR NOW...AND HIGHLIGHT THE THREAT WITH NEAR-BLIZZARD CONDITIONS
POSSIBLE IN THE REMAINDER OF THE PRODUCT SUITE AND SPECIAL WEATHER
STATEMENT. PROBABILITIES FOR HALF-MILE VISIBILITIES USING THE
BAGGALY BLOWING SNOW MODEL TAKING INTO ACCOUNT SNOW AGE AND THE
LACK OF SIGNIFICANT FALLING SNOW PRODUCE RESULTS THAT DO NOT FAVOR
BLIZZARD CRITERIA BEING MET. FURTHERMORE...THE STRENGTH OF
ISALLOBARIC FORCING AND WINDS AT THE TOP OF THE MIXED LAYER
DECREASE THROUGH THE DAY...BEING GREATEST PRIOR TO THE PRE-FRONTAL
INVERSION BEING BROKEN. CERTAINLY AT LEAST A WINTER WEATHER
ADVISORY FOR BLOWING SNOW WILL BE NEEDED FOR THE SOUTHWEST...AND
POSSIBLY INTO THE SOUTH CENTRAL. GIVEN FURTHER EVALUATION
TODAY.... WOULD NOT BE SURPRISED IF A BLIZZARD WATCH IS ISSUED.
THEREAFTER...THE DE-AMPLIFICATION OF THE ANOMALOUS UPPER LEVEL
PATTERN IS SLOWER WITH THE 15/00 UTC GUIDANCE CONSENSUS COMPARED
TO PREVIOUS RUNS...WITH A RECOVERY FROM ARCTIC AIR LIKELY DELAYED
UNTIL LATE NEXT WEEK AT THE EARLIEST.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1220 PM CST SAT NOV 15 2014
MVFR CIGS WILL CONTINUE TO DRIFT SOUTH OVER WESTERN AND CENTRAL
NORTH DAKOTA THIS AFTERNOON. ISOLATED FLURRIES ARE EMBEDDED WITHIN
THE STRATUS DECK. INDICATED VCSH IN THE AFTERNOON TAFS TO ACCOUNT
FOR THESE FLURRIES. OTHERWISE...VFR CONDITIONS ARE EXPECTED TO
DEVELOP OVERNIGHT. A COLD FRONT WILL THEN SWEEP ACROSS THE STATE
FROM NORTH TO SOUTH SUNDAY MORNING...WITH WINDY CONDITIONS
DEVELOPING IN ITS WAKE SUNDAY AFTERNOON. BLOWING SNOW WILL BE
POSSIBLE MAINLY OVER KDIK SUNDAY...WITH IFR VSBYS EXPECTED.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...TM
SHORT TERM...KS
LONG TERM...AYD
AVIATION...TM
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
1126 AM CST SAT NOV 15 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 415 AM CST SAT NOV 15 2014
FOCUS ON THE SNOW EVENT CURRENTLY UNDERWAY ACROSS OUR WESTERN
CWA... EXPECTED TO PROGRESS EAST THROUGH THE REGION OVER THE
NEXT 24 HOURS. OVERALL LOOKING AT A BROAD ISENTROPIC UPGLIDE
AHEAD OF OPEN WAVE...WHICH SHOULD RESULT IN FAIRLY UNIFORM SNOW
AMOUNTS ACROSS THE REGION. HOWEVER...CURRENT RADAR SHOWING A COUPLE
MORE DISTINCT BANDS NEAR MID LEVEL /750-650MB/ FRONTAL BOUNDARIES
PER RAP MODEL...SO COULD SEE SOME AREAS OF ENHANCEMENT THROUGHOUT
THE DAY. FRONTOGENESIS APPEARS TO BE FAIRLY TRANSIENT THOUGH...SO DO
NOT EXPECT HEAVIER BANDS TO SIT IN ANY ONE LOCATION FOR PROLONGED
PERIOD OF TIME. NORTHERN BAND APPEARS TO BE A LITTLE FARTHER NORTH
THAN PREVIOUSLY EXPECTED THOUGH...AIMING TOWARD THE HIGHWAY 14
CORRIDOR THROUGH THE MORNING. HAVE BUMPED UP SNOW AMOUNTS A BIT IN
THESE AREAS AS A RESULT...AND EXPANDED ADVISORY NORTHWARD TO COVER
ENTIRE CWA FOR WIDESPREAD 3 TO 5 INCHES.
IN ADDITION TO POTENTIALLY HIGHER BANDS...CONCERN FOR THIS EVENT IS
HIGH SNOW RATIOS GIVEN STRONG LIFT WITHIN DEEP DENDRITIC LAYER...
AND LIGHT WINDS ALLOWING DENDRITIC SNOW FLAKES TO HOLD TOGETHER.
GENERALLY STICKING WITH 16-18:1 RATIOS FOR BULK OF THE SNOWFALL...
BUT SOME MODELS INDICATE A BIT HIGHER...WHICH COULD PUSH AMOUNTS
CLOSER TO 6 INCH RANGE IN SOME AREAS. STILL EXPECT SNOW TO BE DONE
IN MOST AREAS BY MID-LATE EVENING...BUT WAVE IS A BIT SLOWER IN
DEPARTING THIS EVENING...SO EXTENDED ADVISORY TIMING IN OUR FAR
EAST THROUGH MIDNIGHT TONIGHT. GIVEN FLUFFY NATURE OF SNOWFALL...
COULD SEE A LITTLE BLOWING/DRIFTING OF FRESH SNOW AS NORTHWEST WINDS
PICK UP BEHIND THE FRONT ACROSS OUR SOUTHWEST AREAS THIS AFTERNOON
AND EVENING...AND WILL CONTINUE MENTION OF PATCHY BLOWING SNOW
THROUGH PARTS OF THE MISSOURI RIVER VALLEY. STRONGER WINDS OCCUR
AFTER BULK OF ACCUMULATION IS OVER THOUGH...SO AT THIS TIME HAVE NOT
EXTENDED HEADLINES TO COVER ANY BLOWING SNOW THREAT.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 415 AM CST SAT NOV 15 2014
ON SUNDAY...INTENSIFYING LOW PRESSURE TRACKING THROUGH THE UPPER
MISSISSIPPI VALLEY/WESTERN GREAT LAKES REGION WILL PULL A COLD FRONT
THROUGH OUR AREA IN THE AFTERNOON. WHILE WINDS WILL INITIALLY BE OUT
OF THE WEST/SOUTHWEST EARLY IN THE DAY...THEY WILL TURN AROUND TO
THE NORTHWEST WITH THE PASSAGE OF THE SYSTEM...AND PICK UP IN A COLD
AIR ADVECTION REGIME. WITH THIS...GUSTS WILL RAMP UP TO 20 TO 30 KTS
ACROSS THE AREA. IN RESPONSE TO THIS...WILL BEGIN TO HAVE AREAS OF
BLOWING SNOW WITH FRESH SNOW COVER ON THE GROUND. WILL ALSO SEE THE
POSSIBILITY OF SCATTERED FLURRIES OVER PORTIONS OF THE AREA WITH
SOME CLOUD COVER AND VERY COLD THERMAL PROFILES SUPPORTIVE OF
DENDRITIC GROWTH. IN A THE WEST/SOUTHWESTERLY FLOW OUT AHEAD OF THE
FRONT...THE MISSOURI RIVER VALLEY WILL HAVE THE OPPORTUNITY TO WARM
INTO THE MID 20S BEFORE BEGINNING TO DROP OFF IN THE AFTERNOON AS
THE COLDER AIR FEEDS INTO THE AREA. BACK TO THE NORTH AND
EAST...HIGHS WILL ONLY MAKE IT INTO THE UPPER TEENS TO LOWER 20S.
STRONG GUSTY NORTHWESTERLY WINDS WILL PERSIST FOR SUNDAY NIGHT AND
MONDAY...KEEPING THE POSSIBILITY OF BLOWING SNOW ACROSS THE AREA
THROUGH THE PERIOD. THE WINDS WILL KEEP TEMPERATURES FROM DROPPING
OFF TOO DRAMATICALLY ON SUNDAY NIGHT...THOUGH STILL COLD WITH LOWS
IN THE SINGLE DIGITS. IN AN INCREASINGLY COLD AIRMASS WITH MONDAY
925 MB TEMPERATURES PROGGED TO BE JUST EITHER SIDE OF -15 C...IT
WILL BE A BITTERLY COLD DAY WITH HIGHS IN THE LOWER TO MID TEENS.
WITH THE AFOREMENTIONED WINDS...WIND CHILLS WILL BE FIERCE...RUNNING
IN THE SINGLE DIGITS BELOW ZERO TO TEENS BELOW ZERO.
WINDS WILL THEN RAMP DOWN ON MONDAY NIGHT AS A SURFACE RIDGE AXIS
SLIDES CLOSER TO THE AREA...BRINGING AN END TO ANY BLOWING SNOW.
STILL ENOUGH WIND HOWEVER TO KEEP OVERNIGHT LOWS SOMEWHAT IN
CHECK...BOTTOMING OUT JUST EITHER SIDE OF ZERO.
FOR THE REMINDER OF NEXT WEEK...THERE WILL BE A SLIGHT MODERATION OF
TEMPERATURES...ALBEIT STILL MUCH BELOW NORMAL...IN A NORTHWESTERLY
UPPER LEVEL FLOW. THIS WOULD BE MOST APPARENT TOWARD THE END OF THE
WEEK WHEN HIGHS ON FRIDAY COULD CLOSE IN ON THE LOWER 30S THROUGH
THE MISSOURI RIVER VALLEY. THERE DOES NOT APPEAR TO BE ANY
SIGNIFICANT PRECIPITATION PRODUCERS THROUGH THE PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1124 AM CST SAT NOV 15 2014
MVFR TO OCCASIONAL IFR CONDITIONS IN SNOW TODAY...WITH CONDITIONS
GRADUALLY IMPROVING THE THE OVERNIGHT HOURS. WHILE MAINLY VFR
CONDITIONS ARE EXPECTED AFTER ABOUT 9Z TONIGHT IN MOST LOCATIONS
SOME PATCHY MVFR CEILINGS WILL BE POSSIBLE TOMORROW. BE PREPARED
FOR VERY STRONG WINDS AND REDUCED VISIBIITY IN BLOWING SNOW SUNDAY
NIGHT INTO MONDAY AFTERNOON.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...WINTER WEATHER ADVISORY UNTIL 9 PM CST THIS EVENING FOR SDZ039-
040-054>056-060>062-065>071.
WINTER WEATHER ADVISORY UNTIL 3 PM CST THIS AFTERNOON FOR SDZ038-
050-052-053-057>059-063-064.
MN...WINTER WEATHER ADVISORY UNTIL 9 PM CST THIS EVENING FOR MNZ071-
072-080-089-097-098.
WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR MNZ081-
090.
IA...WINTER WEATHER ADVISORY UNTIL 9 PM CST THIS EVENING FOR IAZ001-
012-020-031.
WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR IAZ002-
003-013-014-021-022-032.
NE...WINTER WEATHER ADVISORY UNTIL 9 PM CST THIS EVENING FOR NEZ013-
014.
&&
$$
SHORT TERM...JH
LONG TERM...JM
AVIATION...08