Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 01/30/14
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1016 AM MST TUE JAN 28 2014
.UPDATE...
&&
.SHORT TERM...WINDS A BIT GUSTY OVER THE HIGHER RIDGES AND ALONG
THE FOOTHILLS AS WELL AS WIND PRONE AREAS. A GUST TO 60 MPH WAS
REPORTED AT CROW HILL EARLIER THIS MORNING. MOST GUSTS WERE IN
THE 30 TO 40 MPH RANGE. SOME BLOWING SNOW ALSO BEING REPORTED.
LATEST RAP AND HRRR KEEP THE GUSTS CONFINED TO THE FOOTHILLS AND
ACROSS PORTIONS OF PARK COUNTY NEAR THE BASE OF THE MOSQUITO RANGE
FOR MUCH OF THE DAY WITH SOME DECREASE BY THE EVENING. OTHERWISE
DRY CONDITIONS TO PREVAIL WITH SOME MODERATING OF TEMPERATURES.
OVERALL...CURRENT FORECASTS LOOK REASONABLE. WILL MAKE SOME
ADJUSTMENTS TO WINDS ALONG FOOTHILLS AND PARK COUNTY FOR THIS
AFTERNOON BASED ON CURRENT CONDITIONS. WILL ALSO LOWER HIGHS ALONG
THE PLATTE RIVER IN WELD COUNTY AS TEMPERATURES THERE MAY STRUGGLE
TO REACH 20 DEGREES. WINDS TO INCREASE AGAIN ACROSS THE HIGHER
MOUNTAINS AND FOOTHILLS OVERNIGHT AS WEST NORTHWEST FLOW ALOFT
INCREASES. LATEST RAP SPATIAL CROSS SECTIONS SHOW CROSS MOUNTAIN
FLOW INCREASING TO AROUND 40 KTS AT MOUNTAIN TOP. WINDS SHOULD
STAY BELOW HIGH WIND CRITERIA.
.AVIATION...OVERALL CURRENT TAFS LOOK ON TRACK WITH VFR PREVAILING.
CURRENT DRAINAGE WINDS TO DECREASE BY THE AFTERNOON. LATEST RAP
AND HRRR CONTINUE TO SHOW WINDS SHIFTING COUNTERCLOCKWISE TO THE
SOUTHEAST...THEN BACK SOUTHWEST BY 21Z. THERE MAY BE A BRIEF SHIFT
TO THE WEST OR NORTHWEST BETWEEN 22Z AND 20Z PER THE RAP. WILL NOT
INCLUDE IN KDEN OR KAPA TAF AT THIS TIME. DRAINAGE TO THEN BECOME
ENHANCED THIS EVENING...WITH SOUTHWESTERLY WINDS AT KDEN AND KAPA
AND WESTERLY AT KBJC. SOME GUSTS TO 25 KTS POSSIBLE AT KBJC AFTER
06Z WITH INCREASING DOWNSLOPE FLOW. SOUTHWEST WINDS TO PERSIST AT
KDEN AND KAPA THROUGH THE DAY WEDNESDAY.
&&
.PREV DISCUSSION... /ISSUED 304 AM MST TUE JAN 28 2014/
SHORT TERM...DRIER AIR IN NW FLOW ALOFT WILL SPREAD ACROSS THE
AREA THIS MORNING BRINGING AN END TO THE LIGHT SNOW IN THE MTNS
AND ALONG THE FRONT RANGE. SOME FOG CONTINUED AROUND THE DENVER
AREA HOWEVER MOST OF IT WAS OVER THE ERN AND SRN SUBURBS BASED ON
GOES R IMAGERY AND WEB CAMS. I WOULD EXPECT THIS FOG TO QUICKLY
BURN OFF BY SUNRISE.
OTHERWISE FOR THIS AFTN WILL HAVE A DRY FCST WITH SOME SLIGHT
MODERATION IN TEMPERATURES. BASED ON CURRENT DATA WILL KEEP AFTN
HIGHS IN THE 20S ACROSS MOST OF NERN CO HOWEVER AREA AROUND DENVER
READINGS COULD REACH THE LOWER 30S.
FOR TONIGHT MOISTURE WILL INCREASE IN THE NRN MTNS AFTER MIDNIGHT
WITH A CHC OF LIGHT SNOW MAINLY IN ZN 31. WINDS WILL BE GUSTY AT
TIMES AS WELL IN THE HIGHER MTNS AND FOOTHILLS BUT SPEEDS WILL
REMAIN BLO HIGH WIND CRITERIA.
LONG TERM...MODELS KEEP A JET MAXIMUM OVER THE FORECAST AREA
WEDNESDAY THROUGH THURSDAY NIGHT. FIRST IT IS NORTH-NORTHWESTERLY
IN DIRECTION WEDNESDAY...THEN NORTHWESTERLY WEDNESDAY NIGHT...THEN
WESTERLY LATER THURSDAY AND THURSDAY NIGHT. ALL THE WHILE SPEEDS
ARE 110 TO 140 KNOTS. THE QG VERTICAL VELOCITY FIELDS HAVE
DOWNWARD SYNOPTIC ENERGY FOR THE CWA WEDNESDAY...THEN UPWARD
MOTION WEDNESDAY NIGHT THROUGH THURSDAY NIGHT. THE BOUNDARY LAYER
WINDS ARE PROGGED TO BE DOWNSLOPING WEDNESDAY INTO EARLY THURSDAY
MORNING. THEN SOUTHEASTERLIES ARE PROGGED FOR THE PLAINS AND
FOOTHILLS. FOR MOISTURE...WEDNESDAY STARTS OUT PRETTY DRY...BUT IT
INCREASES RAPIDLY AND SUBSTANTIALLY OVER THE MOUNTAINS BY
AFTERNOON. MOISTURE IS VERY DEEP IN THE MOUNTAINS WEDNESDAY
AFTERNOON THROUGH THURSDAY NIGHT. THERE IS PLENTY OF MID AND UPPER
LEVEL MOISTURE FOR THE PLAINS WEDNESDAY AFTERNOON INTO THURSDAY.
BY THURSDAY AFTERNOON AND NIGHT...MOISTURE EVEN GETS INTO THE
LOWER LEVELS OF THE PLAINS. THE QPF FIELDS ON THE MODELS HAVE
FAIRLY SIGNIFICANT MEASURABLE PRECIPITATION AMOUNTS OVER THE
MOUNTAINS WEDNESDAY MID DAY THROUGH THURSDAY NIGHT. RAN THE
OROGRAPHIC SNOW MODEL AND THE HIGH MOUNTAIN ZONES LOOK TO RECEIVE
SIGNIFICANT AMOUNTS OF SNOWFALL. WITH THE MOISTURE...UPWARD
SYNOPTIC SCALE ENERGY...WIND SPEEDS/DIRECTIONS AND THE JET AROUND
WILL GO WITH A WATCH RIGHT NOW FROM WEDNESDAY AFTERNOON THROUGH
THURSDAY NIGHT. WILL GO SOME MINOR POPS OVER THE PLAINS THURSDAY
AFTERNOON AND NIGHT. FOR TEMPERATURES...WEDNESDAY`S HIGHS ARE SOME
7 TO 11 C WARMER THAN TODAY`S. THURSDAY`S READINGS COOL BACK DOWN
ABOUT 4-7 C FROM WEDNESDAY`S. FOR THE LATER DAYS...FRIDAY THROUGH
MONDAY...MODELS HAVE ZONAL FLOW OVER THE CWA THROUGH SUNDAY
NIGHT...WITH A WEAK UPPER TROUGH EMBEDDED ON FRIDAY. MODELS SHOW
AN UPPER TROUGH TO MOVE ACROSS COLORADO MONDAY LATE INTO TUESDAY.
AVIATION...AREAS OF FOG AND LOW CEILINGS CONTINUE TO AFFECT THE
AIRPORT AS VISIBILITIES HAVE BEEN AROUND 1/2 MILE SINCE LATE LAST
EVENING. NONE OF THE HI RES MODELS SHOW THIS FOG BUT WOULD THINK
IT WOULD BURN OFF BY SUNRISE. OTHERWISE SHOULD SEE VFR CONDITIONS
TODAY AND TONIGHT. WINDS HAVE BEEN LIGHT WSW BUT EXPECT THEM TO
BECOME MORE SSE BY MID TO LATE MORNING THRU THE AFTN HOURS.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WATCH FROM WEDNESDAY MORNING THROUGH LATE THURSDAY
NIGHT FOR COZ031-033-034.
&&
$$
SHORT TERM...D-L
LONG TERM....RJK
AVIATION...D-L
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
1016 PM MST MON JAN 27 2014
.UPDATE...
ISSUED AT 1010 PM MST MON JAN 27 2014
AT 9PM THE COLD FRONT WAS STRETCHED FROM NE UTAH SE INTO THE I70
CORRIDOR NEAR RIFLE THEN SOUTH DOWN THE CONTINENTAL DIVIDE. THE NW
COLORADO MTNS LOOK TO HAVE ACCUMULATED 5-10 INCHES. THE CENTRAL
MTNS FROM SUNLIGHT MTN TO ASPEN AND ON TO LEADVILLE HAVE SEEN A
PERIOD OF MODERATE TO HEAVY SNOW ALONG THIS FRONTAL BAND THIS
EVENING. THE 00Z NAM AND 03Z RAP SHOW A RAPID DIMINISHING OF
SNOWFALL TOWARDS MIDNIGHT AS THE FRONTAL FORCING SHIFTS TO THE SE
AND ONLY OROGRAPHIC NW FLOW WILL CONTINUE TO PRODUCE LIGHT
SNOWFALL ALONG THE ELKS AND NW SAN JUAN MTNS. CURRENT RADAR TRENDS
SUPPORT THIS WITH SOME ENHANCEMENT BETWEEN MONTROSE AND OURAY.
THE COLDEST 700MB/MTN TOP TEMPS OCCUR TUESDAY MORNING. VALLEY
LOW TEMPERATURES WILL LIKELY PLUMMET TONIGHT IN THE NORTHERN
VALLEYS BUT GRADIENT WINDS IN THE CENTRAL AND SOUTHERN VALLEYS
WILL KEEP THE TEMPERATURES SOMEWHAT MILDER. THEN WARM ADVECTION
BEGINS ON TUESDAY AND CONTINUES INTO WEDNESDAY. MTN TOP WINDS
REMAIN BREEZY TO WINDY WITH G35 POSSIBLE TUESDAY OVER HIGH EXPOSED
TERRAIN. THESE WINDS WILL INCREASE ON WEDNESDAY TO G50 NORTH/G30
SOUTH.
THE PROLONGED SNOW EVENT STARTS ACROSS THE NORTHERN MTNS ON
WEDNESDAY. THE LATEST MODELS CONTINUE TO PRODUCE IMPRESSIVE
SNOWFALL THROUGH FRIDAY. THE DEVIL IS IN THE DETAILS...BUT THE
LATEST MODELS ARE PRODUCING AROUND 2 FEET OF NEW SNOW OVER THE CO
NORTHERN AND CENTRAL MTNS BY FRIDAY AFTERNOON.
&&
.SHORT TERM...(TONIGHT THROUGH TUESDAY NIGHT)
ISSUED AT 331 PM MST MON JAN 27 2014
A FRONTAL BAND WILL GRADUALLY MOVE SOUTH OVER THE CO NORTHERN AND
CENTRAL MTNS THIS EVENING. MOST OF ITS ENERGY WILL CONTINUE
TRANSFERRING EAST AND OVER THE FRONT RANGE. NORTHWESTERLY
OROGRAPHIC FLOW WILL HELP PRODUCE ADVISORY LEVEL SNOW
ACCUMULATIONS IN THE PARK AND GORE RANGES AND THE FLATTOP
WILDERNESS THROUGH ABOUT MIDNIGHT. LIGHT ACCUMULATIONS WILL ALSO
CAUSE SOME TRAVEL PROBLEMS OVER VAIL PASS THROUGH THIS EVENING.
THE MOISTURE AND DYNAMIC UPLIFT SHOULD ALL MOVE EAST OF THE AREA
AROUND MIDNIGHT...WITH OROGRAPHIC FLOW CONTINUING TO HELP PRODUCE
SNOWFALL UNTIL THE MOISTURE DIMINISHED LATE AT NIGHT.
TUE AND TUE NIGHT SHOULD BE DRY UNDER NORTHWEST FLOW ON THE EAST
SIDE OF A BUILDING RIDGE OVER THE WESTERN GREAT BASIN AND WEST
COAST. TUE SHOULD BE A FEW DEGREES COOLER ON MAX TEMPS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 331 PM MST MON JAN 27 2014
WATER VAPOR SHOWING A STRONG BRANCH OF THE POLAR JET ARRIVING TO THE
NORTHWEST COAST THIS AFTERNOON WITH A GOOD FETCH OF UPSTREAM
MOISTURE. DERIVED SATELLITE IMAGERY IN THIS PLUME SUGGESTS PWATS ARE
RUNNING OVER 200 PERCENT AND WE SHOULD SEE RAOBS PICK THIS UP IN THE
WEST WITH THE NEXT FEW BALLOON LAUNCHES. THE PACIFIC JET WILL BE
ARCING OVER THE NORTHERN ROCKIES THROUGH WEDNESDAY NIGHT DRAGGING
THE MOISTURE EASTWARD INTO THE GREAT BASIN. MODEL TIME SERIES AT GJT
ARE SHOWING PWATS HITTING 0.50 OF AN INCH OR +2 STD DEVIATIONS ABOVE
NORMAL FOR LATE JANUARY...VERY WET. THIS MOISTURE ALONG WITH
WESTERLY FLOW WILL INITIATE OROGRAPHIC SHOWERS OVER THE NORTHERN
COLORADO HIGH COUNTRY THROUGH THE DAY WEDNESDAY. THE FORCING ATTM
JUST DOES NOT LOOK STRONG ENOUGH TO GET SIGNIFICANT PRECIPITATION TO
THE LOWER ELEVATIONS. ONE CHALLENGE WILL CONTINUE TO BE
TEMPERATURES WITH RESPECT TO MIXING OUT COLD AIR AND CLOUD COVER.
GUIDANCE TRENDS ARE GENERALLY SLIGHTLY COOLER SO HAVE MADE SOME
SMALL ADJUSTMENTS OR STAYED NEAR THE COOLER GUIDANCE NUMBERS.
AN AGGRESSIVE ARCTIC WAVE WILL BE MOVING THROUGH THE EASTERN
CANADIAN PRAIRIES ON THURSDAY. IN IT/S WAKE THE ARCTIC FLOW AND
PACIFIC FLOW WILL BE FORCED TO MERGE JUST UPSTREAM OF THE ROCKIES.
IN TURN THIS WILL FORCE THE UPPER JET SOUTHWARD INTO THE NORTHERN
GREAT BASIN THURSDAY NIGHT...THEN INTO THE 4 CORNERS REGION BY LATE
FRIDAY NIGHT. ADVECTION OF WAVES OR VORTICITY THROUGH THE FLOW...MID
LEVEL FRONTOGENESIS IN RESPONSE TO THE BAROCLINIC ZONE ASSOCIATED
WITH THE MERGED FLOW...AND THE JET WILL COMBINE TO SIGNIFICANTLY
ENHANCE LARGE SCALE ASCENT OVER OUR CWA. WITH THE MOISTURE IN
PLACE SIGNIFICANT PRECIPITATION SEEMS LIKELY. THE ONLY THING
LACKING IS BETTER MODEL AGREEMENT TO BOOST CONFIDENCE ON SOME
FINER DETAILS. IN SOME CASES MODELS ARE ALMOST A STATE OFF.
WITH WESTERLY FLOW HOWEVER OUR NORTHERN AND CENTRAL MOUNTAINS LOOK
SET UP FOR A LONG DURATION PRECIPITATION EVENT WITH LIQUID AMOUNTS
IN EXCESS OF AN INCH AND HALF. FOR NOW HAVE PLACED A WINTER STORM
WATCH IN THESE AREAS AND HOPE FOR BETTER AGREEMENT WITH THE
UPCOMING MODEL RUNS. THERMAL PROFILES AND A BETTER IDEA OF WHERE
THE MID LEVEL FRONTAL BAND WILL BE SETTING UP WILL HELP...BUT IT
APPEARS SOME OF THE NORTHERN VALLEYS AND THE I-70 CORRIDOR FROM
SILT EASTWARD WILL BE SUSCEPTIBLE TO HEAVY SNOW AS WELL.
TEMPERATURES LOOK TO MODERATE THURSDAY WITH THE INFLUX OF THE
PACIFIC MOISTURE AND WARMER AIR MASS. AS THE JET SAGS SOUTHWARD
AND A GENERAL TROF SETS UP IN THE WEST...TEMPERATURES WILL BE
COOLING FOR THE WEEKEND. THE REMAINDER OF THE WEEKEND LOOKS
FAIRLY QUIET WITH THE NEXT SYSTEM SLATED TO COME THROUGH EARLY
NEXT WEEK AND BRING ANOTHER CHANCE OF PRECIPITATION TO THE AREA.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1010 PM MST MON JAN 27 2014
THE FRONTAL BAND IS VERY QUICKLY SHIFTING TO THE EAST OF THE
CONTINENTAL DIVIDE WITH IMPROVING CONDITIONS AT ALL TAF SITES.
MTN TOPS WILL REMAIN FQTLY OBSCURED IN THE EASTERN FORECAST AREA
FROM RABBIT EARS SOUTH TO SLUMGULLION PASS THROUGH 15Z TUESDAY.
THEN IMPROVING CONDITIONS. NWLY MTN TOP WINDS WILL REMAIN STRONG
THROUGH TUESDAY PRODUCING MODERATE TO STRONG TURBULENCE. OTHERWISE
VFR CONDITIONS SHOULD PREVAIL TUESDAY AND TUESDAY NIGHT.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WINTER STORM WATCH FROM WEDNESDAY AFTERNOON THROUGH FRIDAY
EVENING COZ010-012.
WINTER WEATHER ADVISORY UNTIL 11 PM MST THIS EVENING ABOVE 9000
FEET FOR COZ004.
WINTER STORM WATCH FROM WEDNESDAY AFTERNOON THROUGH FRIDAY
EVENING COZ004-013.
UT...NONE.
&&
$$
UPDATE...JOE
SHORT TERM...CC
LONG TERM...15
AVIATION...JOE
AREA FORECAST DISCUSSION
NWS ALBANY NY
956 PM EST WED JAN 29 2014
.SYNOPSIS...
HIGH PRESSURE WILL CREST TO OUR SOUTH TONIGHT...BEFORE SLIDING OFF
THE NEW ENGLAND COAST ON THURSDAY. AFTER A COLD START TO THE DAY
THURSDAY...A RETURN SOUTHERLY FLOW WILL RESULT IN TEMPERATURES
MODERATING TO NEAR NORMAL. A WEAK DISTURBANCE WILL MOVE ACROSS THE
AREA ON FRIDAY...BRINGING JUST A FEW LIGHT SNOW SHOWERS OR FLURRIES
WITH EVEN WARMER TEMPERATURES. MORE UNSETTLED WEATHER IS POSSIBLE
FOR THE UPCOMING WEEKEND...ALTHOUGH DETAILS ARE NOT CERTAIN AT THIS
TIME.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
AS OF 930 PM EST...MAIN ATTENTION HAS BEEN THE LAKE EFFECT SNOW
DOWNWIND OF LAKE ONTARIO. CSTAR INLAND EXTENT HAS BEEN PERFORMING
OUTSTANDING WITH THE LIMITS AROUND 55 MILES WHICH PLACES THE BAND
RIGHT NEAR THE NORTHERN HERKIMER COUNTY LINE. AS SEEN IN THE H2O
VAPOR IMAGERY...A SMALL SHORT WAVE WAS MOVING ACROSS WESTERN LAKE
ONTARIO AS THIS MAY TEMPORARILY RAISE THE INVERSION LEVEL /WHICH
WAS CAPTURED IN THE BUF 00Z SOUNDING/ FOR THE BAND TO MOVE A
LITTLE FURTHER INLAND AS SUGGESTED BY WRF/HRRR EXPERIMENTAL
REFLECTIVITIES AND RUC13 LOW LEVEL CONVERGENCE FIELDS AND
ASSOCIATED QPF. SO WE WILL INCREASE POPS AND ACCUMULATIONS FOR
NORTHERN HERKIMER COUNTY UP TO 2 INCHES FOR WESTERN PORTIONS OF
THE COUNTY /IN THE VICINITY OF MOSHIER FALLS/ PER THE CARIBOU SNOW
ACCUMULATION TECHNIQUE. OTHERWISE...MOCLR SKIES AS TEMPS ARE
RUNNING A COUPLE DEGREES COOLER AND MADE SLIGHT ADJUSTMENTS TO THE
HOURLY FORECASTS OVERNIGHT BUT KEEP THE PREVIOUS MIN TEMP
ADJUSTMENTS FROM THE 700 UPDATE.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/...
DRY AND TRANQUIL CONDITIONS ARE EXPECTED THURSDAY WITH THE START OF
A WARMING TREND DUE TO A DEVELOPING SOUTHERLY FLOW. COMBINED WITH
AMPLE SUNSHINE...MOST AREAS SHOULD REACH THE WELL INTO THE 20S
DESPITE THE COLD START.
MAINLY DRY WEATHER SHOULD PERSIST THROUGH MUCH OF THURSDAY
NIGHT...ALTHOUGH AN UPPER LEVEL DISTURBANCE AND WEAKENING COLD FRONT
WILL APPROACH FROM THE GREAT LAKES. THERE COULD BE ENOUGH LIFT FOR A
FEW LIGHT SNOW SHOWERS BEFORE SUNRISE FRIDAY ACROSS THE WESTERN
MOHAWK VALLEY AND WESTERN ADIRONDACKS MAINLY DUE TO SOUTHERLY
UPSLOPE. THIS DISTURBANCE WILL CONTINUE TO WEAKEN...WITH ONLY A
SUBTLE SURFACE TROUGH MEANDERING ACROSS THE AREA ON FRIDAY. WILL
MENTION SLIGHT CHANCE TO CHANCE POPS WITH THE HIGHER VALUES WEST OF
THE HUDSON VALLEY. DESPITE MOSTLY CLOUDY SKIES...TEMPERATURES SHOULD
CONTINUE TO MODERATE INTO THE 30S IN VALLEY LOCATIONS WITH A
SOUTHWEST BREEZE DEVELOPING.
NOT MUCH IN THE WAY OF ANY DISCERNIBLE FORCING SEEN FOR FRIDAY
NIGHT...SO ONLY SLIGHT CHANCE POPS ACROSS THE AREA. TEMPERATURES
SHOULD BE ABOVE NORMAL WITH GENERALLY CLOUDY SKIES AND A LIGHT
SOUTHERLY BREEZE.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
UNSETTLED CONDITIONS EXPECTED THROUGH THE WEEKEND WITH SOME
IMPROVEMENTS FOR EARLY NEXT WEEK...BEFORE ANOTHER POTENTIAL SYSTEM
IMPACTING THE REGION AFTER THE LONG RANGE PERIOD.
LATEST NCEP MODEL SUITE AND INTERNATIONAL GUIDANCE ARE IN RATHER
GOOD AGREEMENT WITH SYNOPTIC PATTERN SETTING UP FOR THE UPCOMING
WEEKEND. ELONGATED TROUGH AXIS OVER THE WESTERN NOAM AND TIGHTENING
BAROCLINIC ZONE OVER THE CENTER OF THE NATION WILL AID IN A
DEVELOPMENT OF OVERRUNNING AND SURFACE WAVE DEVELOPMENT. THE
CONSENSUS FAVORS A SURFACE LOW TRACK TO BE WEST AND NORTH OF THE
REGION...HOWEVER...NEAR SURFACE TEMPERATURES WILL BE A CHALLENGE TO
DISLODGE THE ARCTIC AIR THAT HAS BEEN IN PLACE FOR SOME TIME. PER
THE THICKNESS MODIFIED SCHEMES...WE WILL LEAN A LITTLE COLDER WITH A
RAIN/SNOW MIXTURE BUT CAN NOT RULE OUT A PERIOD OF FREEZING RAIN
WITHIN THE ONSET OF PRECIPITATION. THE HEAVIER QPF IS EXPECTED TO
REMAIN WEST AND NORTH OF THE CAPITAL REGION SATURDAY THROUGH
SATURDAY NIGHT.
SUNDAY...SEEMS THE ASSOCIATED FRONTAL BOUNDARY WILL SLIDE EAST OF
THE REGION IN THE MORNING WITH IMPROVING CONDITIONS FOR THE REGION.
SOME LAKE RESPONSE IS POSSIBLE DOWNWIND OF LAKE ONTARIO WHERE WE
WILL KEEP LOW CHANCE POPS AND CLOUDS IN THE FORECAST. H850 TEMPS
DROP BACK TO BELOW -10C. SURFACE ANTICYCLONIC RIDGE AXIS IS EXPECTED
TO CREST OVER THE WESTERN AND CENTRAL GREAT LAKES REGION LATER
SUNDAY TO REDUCE LAKE IMPACTS AND GRADUAL CLEARING SKIES.
THIS SURFACE HIGH IS FORECAST TO STRENGTHEN AND BECOME ELONGATED
THROUGH EARLY NEXT WEEK BEFORE ANOTHER UPPER LOW MOVING ACROSS BAJA
CALIFORNIA AND TRACK ACROSS THE SOUTHERN PLAINS AND INTO THE
MISSISSIPPI VALLEY FOR THE MID WEEK PERIOD.
TEMPERATURES THROUGH THE PERIOD WILL AVERAGE NEAR NORMAL WITH
PRECIPITATION NEAR NORMAL.
&&
.AVIATION /03Z THURSDAY THROUGH MONDAY/...
VFR CONDITIONS ARE EXPECTED AT ALL SITES THROUGH THE ENTIRE TAF
PERIOD.
OUTSIDE OF SOME CU/SC OFF LAKE ONTARIO IMPACTING KGFL...NEAR IDEAL
FLIGHT CONDITIONS WITH NO AVIATION OBSTRUCTIONS EXPECTED. RIDGE
BUILDS IN ACROSS THE AREA TONIGHT INTO THURSDAY.
OUTLOOK...
THURSDAY TO THURSDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
FRIDAY TO FRIDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE
OF SHSN.
SATURDAY TO SUNDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF RA...SN.
SUNDAY NIGHT TO MONDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
NO WIDESPREAD HYDRO PROBLEMS ARE EXPECTED THROUGH THE NEXT FIVE DAYS.
MAINLY DRY CONDITIONS ARE FORECAST THROUGH THURSDAY...WITH JUST
ISOLATED TO SCATTERED LIGHT SNOW SHOWERS OR FLURRIES POSSIBLE LATE
THURSDAY NIGHT THROUGH FRIDAY. SOME ADDITIONAL SNOW OR EVEN RAIN
SHOWERS ARE POSSIBLE SATURDAY INTO SUNDAY AS TEMPERATURES MODERATE.
THIS PRECIPITATION LOOKS TO BE LIGHT AND WILL HAVE LITTLE EFFECT ON
AREA RIVERS AND STREAMS.
COLD TEMPERATURES WILL CONTINUE INTO THURSDAY...THEN FINALLY START
TO MODERATE FRIDAY AND ESPECIALLY INTO THE WEEKEND.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...JPV
NEAR TERM...BGM/JPV
SHORT TERM...JPV
LONG TERM...BGM
AVIATION...FRUGIS/BGM
HYDROLOGY...11/JPV
AREA FORECAST DISCUSSION
NWS ALBANY NY
1247 PM EST TUE JAN 28 2014
.SYNOPSIS...
AN ARCTIC AIR MASS WILL CONTINUE TO ALLOW FOR FRIGID
TEMPERATURES AND LOW WIND CHILL VALUES THIS AFTERNOON THROUGH
TONIGHT. A STORM SYSTEM MOVING UP THE SOUTHEAST COAST WILL REMAIN
WELL SOUTH AND EAST OF OUR REGION...KEEPING DRY WEATHER IN PLACE.
TEMPERATURES WILL SLOWLY MODERATE BACK TOWARDS NORMAL LEVELS BY THE
END OF THE WORK WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1247 PM EST...DRY...BUT VERY COLD...CONDITIONS ARE IN PLACE
THIS AFTERNOON ACROSS THE CWA. SOME HIGH CLOUDS...ASSOCIATED WITH
A WINTER STORM AFFECTING THE GULF COAST AND SOUTHEASTERN US...ARE
MOVING NORTHEAST ACROSS THE SOUTHERN PORTION OF THE
REGION...OTHERWISE...SKIES ARE MAINLY CLEAR. ANY LAKE EFFECT SNOW
OFF LAKE ONTARIO HAS WEAKENED...AND HAS BEEN MAINLY AFFECTING
AREAS CLOSE TO SHORELINE OF THE NORTHEAST CORNER OF LAKE ONTARIO.
OUR LOCAL HIRESWRF AND THE 3KM HRRR ALL SHOW ANY LAKE EFFECT SNOW
REMAINING NORTH AND WEST OF OUR CWA THROUGH THE EVENING HOURS.
TEMPS THIS AFTN LOOK TO HOLD STEADY IN THE SINGLE DIGITS AND TEENS
WITH NW WINDS AROUND 10 MPH.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/...
TONIGHT INTO WEDNESDAY...A RIDGE OF HIGH PRESSURE WILL BE BUILDING
INTO OUR REGION FROM THE SOUTHWEST AS A COASTAL STORM PASSES WELL
SOUTHEAST OF CAPE COD. THIS WILL RESULT IN DRY AND CONTINUED COLD
CONDITIONS WITH LOWS TONIGHT 5 BELOW TO 5 ABOVE ZERO AND HIGHS ON
WEDNESDAY IN THE TEENS TO MID 20S.
DRY WEATHER IS EXPECTED TO REMAIN IN PLACE FOR FOR WEDNESDAY NIGHT
INTO THURSDAY WITH A SLIGHT MODERATING TREND WITH REGARDS TO THE
TEMPERATURE. WINDS WILL ALSO BE MUCH LIGHTER WHICH SHOULD PREVENT
ANY WIND CHILL ISSUES. EXPECT LOWS WEDNESDAY NIGHT TO BE IN THE 5
BELOW TO 5 ABOVE ZERO RANGE WITH HIGHS ON THURSDAY IN THE 20S.
FOR THURSDAY NIGHT ANOTHER CLIPPER TYPE SYSTEM WILL BE MOVING
ACROSS SRN CANADA WITH A TRAILING COLD FRONT CLOSE ENOUGH SUCH
THAT CLOUDY CONDITIONS SHOULD PREVAIL ALONG WITH A CHANCE OF SNOW.
EXPECT LOWS THURSDAY NIGHT TO RANGE FROM THE UPPER SINGLE DIGITS
NORTH TO MID TEENS SOUTH.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
THE EXTENDED FORECAST PERIOD WILL FEATURE A WEAKENING OF THE
PERSISTENT MEAN LONGWAVE TROUGH OVER THE ERN CONUS...AND MORE
SEASONABLE LATE JAN AND EARLY FEB TEMPS. A FEW SYSTEMS WILL IMPACT
NY AND NEW ENGLAND...BUT THERE IS QUITE A BIT OF SPREAD IN THE
TIMING...EVOLUTION...AND TRACK OF A WEEKEND SYSTEM DUE A QUASI-ZONAL
MID AND UPPER LEVEL FLOW IN THE MEDIUM RANGE GUIDANCE AND ENSEMBLES.
FRI-FRI NIGHT...A SHORT-WAVE TROUGH IMPACTS THE FCST AREA WITH A CHC
OF SNOW SHOWERS. THE SFC CYCLONE WILL BE OVER CNTRL QUEBEC WITH THE
SFC PRESSURE TROUGH AND ATTENDANT COLD FRONT BRINGING A CHC OF SNOW
SHOWERS DURING THE DAY. SOME LAKE MOISTURE WILL BE UTILIZED...AND
THE BEST LOW-LEVEL CONVERGENCE WILL BE DOWNSTREAM OF LAKE ONTARIO.
CHC POPS WERE USED FOR THE WRN DACKS...WITH SLIGHT CHC POPS WEST OF
THE HUDSON RIVER VALLEY EARLY ON. DURING THE AFTERNOON...SLIGHT CHC
POPS WERE EXPANDED FOR THE WESTERLY UPSLOPE REGION OF SRN VT...THE
NRN TACONICS...AND BERKSHIRES. MOST OF THE FCST AREA SHOULD STAY
DRY. THE COLD ADVECTION WITH THE TROUGH AND COLD FRONT...IS NOT AS
IMPRESSIVE AS ITS PREDECESSORS OVER THE PAST WEEK TO 10 DAYS. H850
TEMPS FALL BACK TO -10C TO -15C OVER THE CWA. MAX TEMPS CLOSE TO A
WPC/MOSGUIDE BLEND WERE ACCEPTED WITH M20S TO L30S OVER THE
MTNS...AND LOWER TO M30S IN THE VALLEYS. EXPECT LOWS IN THE TEENS
AND 20S WITH WEAK SFC RIDGING BUILDING INTO THE REGION BRIEFLY.
SAT-SAT NIGHT...CHALLENGING PORTION OF THE FCST WHERE THE GFS AND
ECMWF ARE IN TWO DIFFERENT CAMPS IN TERMS OF THE NEXT SYSTEM TO
POTENTIALLY IMPACT THE FCST AREA. A RATHER FLAT UPPER LEVEL TROUGH
WILL BE OVER THE NRN HALF OF THE CONUS. THE GFS BRINGS A WAVE ALONG
THE OLD FRONTAL BOUNDARY OVER THE OH VALLEY AND MID ATLANTIC
REGION. THE LOW LEVEL BAROCLINIC ZONE STRENGTHENS OVER NY AND
PA...AS THE SFC WAVE MOVES ALONG THE PA/MD BORDER BY 00Z/SUN TO EAST
OF NEW ENGLAND BY 06Z/SUN. AN OVER RUNNING SNOW EVENT WOULD SET UP
BASED ON THE CRITICAL PARTIAL THICKNESSES AND THE THERMAL PROFILES.
ALSO...THE QPF WOULD INDICATE A LIGHT TO MODERATE SNOW
EVENT...ESPECIALLY NORTH OF THE MID HUDSON VALLEY. SOME RAIN COULD
MIX IN BRIEFLY THERE. THE ECMWF...ON THE HAND...AMPLIFIES THE
TROUGH OVER THE UPPER MIDWEST AND GREAT LAKES REGION...AND LIFTS THE
SFC WAVE WEST OF THE REGION THROUGH THE CNTRL AND ERN GREAT LAKES.
THIS WOULD BE A WARMER SOLUTION...WITH SOME RAIN OR SNOW SHOWERS ON
SAT...AND A COLD FRONTAL PASSAGE SAT NIGHT...WITH THE SFC CYCLONE
MOVING ACROSS SRN QUEBEC. THE LATEST ENSEMBLES SHOW QUITE A BIT OF
SPREAD...THOUGH THE MAJORITY OF THE GEFS PLUMES THIS CYCLE FOR ALY
FAVOR A COLDER SOLUTION WITH SNOW /A FEW SIGNIFICANT RAIN MEMBERS/.
OUR FORECAST REFLECTS A WPC/GFS SCENARIO AT THIS POINT WITH AT LEAST
SOME SNOW POSSIBLE IN THE AFTERNOON INTO THE EARLY EVENING. THE
WARM ADVECTION AND POSSIBLE S/SW FLOW WILL ALLOW MAX TEMPS TO GET
INTO THE U20S TO L30S NORTH OF THE CAPITAL REGION...AND LOWER TO
M30S FROM THE TRI CITIES SOUTH...WITH A FEW U30S POSSIBLE IN THE MID
HUDSON VALLEY AND NW CT. POPS WERE KEPT IN THE HIGH CHC CATEGORY
DURING THE DAY INTO THE NIGHT TIME PERIOD. LOW TEMPS WITH THE FROPA
WILL BE IN THE TEENS NORTH AND WEST OF THE CAPITAL REGION/UPPER
HUDSON VALLEY...AND LOWER TO M20S TO THE SOUTH AND EAST.
SUNDAY-SUNDAY NIGHT...THE FRONT SWINGS EAST OF THE REGION EARLY
SUNDAY MORNING WITH SOME LAKE EFFECT SNOW SHOWERS POSSIBLE EARLY IN
THE DAY. HIGH PRESSURE IS EXPECTED TO QUICKLY RIDGE IN FROM THE
MIDWEST AND OHIO VALLEY TURNING THE LOW AND MID LEVEL FLOW
ANTICYCLONIC AND YIELDING A MOSTLY DRY AND SEASONABLY COLD DAY.
H850 TEMPS OF -10C TO -16C WITH SOME SUNSHINE AND MIXING WILL YIELD
HIGHS CLOSE TO EARLY FEB NORMALS WITH 20S OVER THE HIGH PEAKS AND
U20S TO M30S IN THE VALLEYS. A DECENT RADIATIONAL COOLING NIGHT IS
EXPECTED TO CLOSE THE WEEKEND WITH THE SFC RIDGE BUILDING IN...AND
LOWS FALLING INTO THE SINGLE DIGITS AND TEENS.
MONDAY...THE START OF THE WEEK BEGINS SEASONABLY COLD AND DRY WITH
HIGH PRESSURE OVER THE NORTHEAST BASED ON THE WPC GUIDANCE. ANOTHER
STORM SYSTEM WILL BE ORGANIZING OVER THE SRN PLAINS AND LOWER MS
RIVER VALLEY WHICH COULD IMPACT THE REGION FOR THE MID WEEK.
OVERALL...TEMPS WILL TREND TO NEAR NORMAL READINGS...AND PCPN LOOKS
A LITTLE BELOW NORMAL FOR THE STRETCH.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
ALL THE TAF SITES WILL EXPERIENCE VFR CONDITIONS AS A LOW PRESSURE
SYSTEM ALONG AN EXTENDED COLD FRONT WELL OFF THE ATLANTIC
COASTLINE WILL MOVE NORTHEAST AND STAY WELL SOUTHEAST OF OUR
REGION FROM 00Z TO 12 WEDNESDAY. WITH THE EXCEPTION OF OVERCAST
HIGH CLOUDS ESPECIALLY AT KPOU AND KPSF AS THE SYSTEM DEPARTS AWAY
FROM THE REGION BETWEEN 00Z AND 12Z WEDNESDAY...ALL TAF SITES WILL
SEE TRANQUIL WEATHER CONDITIONS THROUGHOUT THE END OF THE TAF
PERIOD. A WEAK RIDGE OF HIGH PRESSURE WILL BUILD IN FROM THE
SOUTHWEST PRODUCING LIGHT AND VARIABLE WINDS AFTER 12Z WEDNESDAY
WITH SCT CLOUD COVERAGE.
OUTLOOK...
WEDNESDAY NIGHT THROUGH THURSDAY NIGHT...VFR. NO SIG WX.
FRIDAY THROUGH FRIDAY NIGHT...MVFR/VFR. CHANCE -SHSN/-SHRA
SATURDAY THROUGH SUNDAY...VFR. VCSH ON SUNDAY.
&&
.HYDROLOGY...
NO WIDESPREAD HYDRO PROBLEMS ARE EXPECTED THROUGH THIS WEEK.
LITTLE TO NO PRECIPITATION IS EXPECTED ACROSS THE HSA THROUGH THE
REMAINDER OF THE WORK WEEK.
ALONG WITH THE DRY CONDITIONS WILL BE A VERY COLD AIR MASS.
TEMPERATURES WILL AVERAGE 10 TO 20 DEGREES BELOW NORMAL...WITH
OVERNIGHT LOWS BELOW ZERO AT TIMES...ESPECIALLY FOR THE HIGHER
TERRAIN. THIS WILL CONTINUE TO ALLOW ICE ON RIVERS AND LAKES TO
INCREASE AND THICKEN THROUGH THE WEEK.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR
WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...FRUGIS
NEAR TERM...FRUGIS
SHORT TERM...11
LONG TERM...WASULA
AVIATION...LFM
HYDROLOGY...FRUGIS/11
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
525 AM EST TUE JAN 28 2014
...DENSE FOG ADVISORY IN EFFECT THROUGH THE EARLY MORNING HOURS...
.SYNOPSIS...
09Z WATER VAPOR AND H4 RAP ANALYSIS SHOWING AN AMPLIFIED UPPER LEVEL
PATTERN OVER THE CONUS HIGHLIGHTED BY AN EXPANSIVE AND DEEP TROUGH
COVERING THE NATION FROM THE CONTINENTAL DIVIDE TO THE EASTERN
SEABOARD. THIS IS A VERY COLD TROUGH WHICH HAS PLUNGED MUCH OF THE
CENTRAL AND EASTERN PORTIONS OF THE COUNTRY INTO THE DEEP FREEZE.
THIS COLD AIR HAS BEEN FILTERING SOUTH WITH TIME AND WILL BE
INTERACTING WITH DEVELOPING PRECIPITATION ALONG THE NORTHERN GULF
COAST TO PRODUCE A RARE AND POTENTIALLY SIGNIFICANT WINTER WEATHER
EVENT. AS THE GUIDANCE STANDS NOW...THE FROZEN PRECIP WILL BE
STAYING TO THE NORTH OF OUR FORECAST AREA...ALTHOUGH IT MAY BECOME A
VERY CLOSE CALL FOR PARTS OF LEVY COUNTY ON WEDNESDAY...BUT WE WILL
DISCUSS MORE ON THAT BELOW. THE SHORTWAVE IMPULSE WITHIN THE
LONGWAVE TROUGH THAT WILL BE THE MAIN PLAYER FOR THIS PART OF THE
COUNTRY IS NOW DROPPING SOUTHWARD OVER THE CENTRAL STATES AND WILL
QUICKLY PIVOT SOUTHEAST DURING THE NEXT 24-36 HOURS.
THE ISSUE THE MODELS HAVE BEEN HAVING IN RECENT DAYS HAS BEEN THEIR
EVOLUTION REGARDING A SHORTWAVE LOBE OF ENERGY MOVING ACROSS
NORTHERN MEXICO AND JUST HOW QUICKLY...OR IF AT ALL...THIS ENERGY
WOULD BE PICKED UP BY THE LONGWAVE TROUGH AND PULLED/SHEARED ACROSS
THE NORTHERN GULF OF MEXICO. GOTTA GIVE THE NCEP MODEL SUITE CREDIT
ON THIS ONE AS THE GFS/NAM WERE CERTAINLY THE FIRST ONES TO SHOW THE
MORE AGGRESSIVE AND RAPID EJECTION EASTWARD OF THIS ENERGY. MOST OF
THE GUIDANCE HAVE COME ON BOARD WITH THIS SOLUTION NOW GIVING SOME
INCREASED CONFIDENCE IN THE FORECAST FROM PREVIOUS DAYS. THAT BEING
SAID...THERE ARE STILL SOME DIFFERENCES IN THE DETAILS BETWEEN
ENSEMBLE MEMBERS WHICH COULD HAVE IMPACTS ON THE FORECAST.
AT THE SURFACE WE FIND A COLD FRONT SLOWLY DROPPING SOUTH THROUGH
THE FLORIDA BIG BEND. WITH RELATIVELY MOIST LOW LEVEL AHEAD OF IT
ACROSS OUR REGION. CLEAR SKIES AND LIGHT WINDS OVER THE PENINSULA
HAVE ALLOWED WIDESPREAD FOG TO DEVELOP...SOME OF IT VERY DENSE...AND
A DENSE FOG ADVISORY IS IN EFFECT THROUGH THE EARLY MORNING HOURS.
THE HIGHER DEWPOINTS OVER THE RELATIVELY COOLER SHELF WATERS ARE
ALSO LEADING TO AREAS OF DENSE SEA FOG. THIS SEA FOG MAY BE A BIT
MORE STUBBORN TODAY...AND LIKELY WILL NOT BE COMPLETELY OUT OF THE
FORECAST UNTIL THE COLD FRONTAL PASSAGE LATER TODAY AND TONIGHT.
&&
.SHORT TERM (TODAY THROUGH THURSDAY)...
TODAY...OVERALL NOT A BAD WEATHER DAY EXPECTED FOR MUCH OF THE
REGION ONCE WE CAN GET RID OF THE MORNING FOG. AS MENTIONED
ABOVE...THE SEA FOG IS LIKELY TO LINGER LONGER AND MAY AT TIME
REMAIN AN ISSUE ALONG THE IMMEDIATE COAST. COLD FRONT WILL BE
HEADING INTO THE NATURE COAST WITH INCREASING CLOUDS NORTH OF TAMPA
BAY...BUT FURTHER SOUTH...SHOULD SEE A FAIR AMOUNT OF SUNSHINE.
TEMPERATURES WILL RESPOND WITH WIDESPREAD 70S TO AROUND 80 SOUTH OF
THE I-4 CORRIDOR...RANGING TO THE 60S FOR LEVY COUNTY UNDER MORE
CLOUDS AND BETTER SHOWER CHANCES. THE CHANCES FOR SHOWERS WILL
MAINLY BE CONFINED TO OUR NORTHERN NATURE COAST ZONES. THE LIFT WILL
BE SUPPLIED BY A COMBINATION OF THE SYNOPTIC FORCING ASSOCIATED WITH
THE SHORTWAVE APPROACH...AN OVERALL DIFFLUENT UPPER LEVEL FLOW WITH
THE RRQ OF A STRENGTHENING EASTERN U.S. JET...AND ALSO SOME WEAK
UPGLIDE IN THE LOWER LEVELS.
THE INTERESTING THING ABOUT THIS FORECAST IS THAT WE ARE DEALING
WITH WHAT WE CALL AN ANAFRONT CONFIGURATION FOR THIS COLD FRONT.
USUALLY WHEN A FRONT COMES THROUGH WE SEE A BAND OF SHOWERS AHEAD OF
THE BOUNDARY...AND THEN THINGS CLEAR OUT BEHIND IT. THAT
CONFIGURATION IS CALLED KATAFRONT. WITH ANAFRONT...THE BULK OF THE
CLOUDS AND SHOWERS FALL IN THE POST-FRONTAL ENVIRONMENT. SO...AS THE
FRONT PASSES THROUGH THE REGION LATER TODAY AND TONIGHT...OUR SKIES
WILL CLOUD OVER AND SHOWERS WILL BE SPREADING FROM NORTH TO SOUTH.
HOWEVER...LIKE THE OTHER FRONTS...COLDER AND DRIER AIR WILL BE
ARRIVING OVER THE AREA TONIGHT INTO WEDNESDAY. LOW TEMPERATURES
TONIGHT WILL RANGE FROM THE UPPER 30S TOWARD CHIEFLAND TO AROUND 50
FOR THE I-4 CORRIDOR AND AROUND 60 FOR THE FAR SOUTH. TEMPERATURES
WILL THEN NOT MOVE MUCH...OR EVEN MAY FALL AT TIMES DURING
WEDNESDAY.
WEDNESDAY...A MOSTLY CLOUDY...COOL...AND SHOWERY TYPE OF DAY
EXPECTED. MAY TAKE SOME TIME TO GET THE SHOWERS DOWN TOWARD FORT
MYERS...BUT DO EXPECT THEM TO HAVE ARRIVED BY AFTERNOON. THESE
SHOWERS WILL NOT BE CONTINUOUS...BUT RATHER THE "OFF AND ON"
VARIETY. HOWEVER...THE OCCASIONAL RAIN WILL BE FALLING INTO A
CONTINUOUS SUPPLY OF DRIER LOW LEVEL AIR TRYING TO MOVE SOUTH ON
NORTHERLY WINDS. THE DRIER AIR WILL GIVE US A WET-BULB EFFECT WHERE
THE TEMPERATURES COOL IN RESPONSE TO THE PARTIAL EVAPORATION OF THE
RAINDROPS INTO THE DRIER LOW LEVEL AIR. THIS IS WHY ARE TEMPERATURES
WILL HAVE A HARD TIME RISING AND VERY LIKELY MAY FALL DURING THE
DAY. NOT THE BEST DAY FOR OUTDOOR ACTIVITIES. NOW...UP TOWARD
CHIEFLAND...WE WILL NEED TO KEEP A VERY CLOSE WATCH ON THE UPCOMING
MODEL RUNS. AS OF NOW...ANY WET-BULB EFFECTS BRING THE LOW LEVEL
TEMPERATURE PROFILE DOWN VERY CLOSE TO ALLOWING FOR SOME ICE-PELLETS
OR EVEN SOME FREEZING RAIN TO MIX IN AT TIMES. TOOK A VERY CLOSE
LOOK AT A LOT OF BUFKIT SOUNDING DATA FROM NATIONAL AND LOCALLY RUN
MODELS...AND IT LOOKS LIKE TEMPERATURES WILL STAY JUST ABOVE
FREEZING AT THE SURFACE (EVEN WITH THE BEST WET-BULB EFFECTS) AND
PREVENT ANY FREEZING RAIN. HOWEVER...A SUB-FREEZING LAYER ABOVE THE
SURFACE IS STILL POSSIBLE AND MAY LEAD TO A FEW ICE PELLETS AT JUST
ABOUT ANYTIME ON WEDNESDAY OR WEDNESDAY EVENING. THE GFS SOUNDING
FOR CROSS CITY DOES HAVE ABOUT A 1-2 KFT LAYER BELOW FREEZING JUST
ABOVE THE SURFACE LATE WEDNESDAY. SO...IT IS KIND OF A QUESTION OF
WHETHER OR NOT THERE IS STILL ANY PRECIPITATION LEFT OVER BY THIS
TIME. IF A FEW ICE PELLETS DID OCCUR...THERE WOULD NOT BE ANY
IMPACT...BUT JUST MENTIONING FOR MORE OF A CURIOSITY FACTOR. FOR
NOW...THINK THERE IS A BETTER CHANCE THAT WE WILL NOT SEE ICE
PELLETS...AND DID NOT INCLUDE IN THE FORECAST. WILL NEED TO BE
WATCHED CLOSELY THOUGH.
WEDNESDAY NIGHT...MODEL CONSENSUS HAS COME AROUND TO ONE SUPPORTING
A CONTINUED SHOWERY PATTERN. THE BACK EDGE WILL BE TRYING TO MAKE IT
INTO LEVY/CITRUS COUNTIES...AND HENCE THE POTENTIAL PRECIP TYPE
ISSUES IF THE SHOWERS CAN HOLD ON. FURTHER SOUTH...SHOWER CHANCES
ARE STILL IN THE LIKELY CATEGORY. IT WILL COLD AND RAW OUTSIDE...BUT
THERE IS NO CHANCE AS IT STANDS NOW TO SEE ANY ICE PELLETS...JUST A
COLD RAIN. LATE WEDNESDAY NIGHT THOUGH...ONCE THE PRECIP IS GONE FOR
LEVY COUNTY...THERE IS A CHANCE FOR A LIGHT FREEZE...AND PROB
LOOKING AT SOME CHILLY WIND CHILLS DOWN INTO THE 30S AT LEAST AS FAR
SOUTH AS HILLSBOROUGH AND POLK COUNTIES.
THURSDAY...SYNOPTIC FORCING FINALLY BEGINS TO EXIT TO OUR EAST
DURING THE DAY. WILL SHOW BEST SHOWER CHANCES DURING THE MORNING TO
THE SOUTH OF I-4...AND BEGIN A CLEARING TREND IN THE AFTERNOON FOR
ALL AREAS. THE TREND WITH THIS ENTIRE SYSTEM HAS BEEN A SLOWER
CLEARING...SO WOULD NOT BE SURPRISED IF SOUTHERN ZONES HELD ONTO AT
LEAST A CHANCE FOR SHOWERS UNTIL THURSDAY NIGHT. HIGH TEMPS THURSDAY
WILL SOMEWHAT DEPEND ON THE SHOWER COVERAGE...BUT WENT WITH A
MAV/MET BLEND GIVING US LOW TO MID 60S SOUTH...LOW 60S CENTRAL...AND
UPPER 50S NORTH.
&&
.LONG TERM (FRIDAY THROUGH NEXT MONDAY)...
A SHORT WAVE TROUGH EXITS TO THE EAST FOR THE START OF THE PERIOD
WITH ZONAL FLOW ALOFT THE REGION INTO SAT. THEN FLOW BEGINS TO BACK
TO SOUTHWESTERLY AS A SHORT WAVE TROUGH MOVES THROUGH THE WESTERN
THEN CENTRAL CONUS SUN AND MON. SURFACE HIGH PRESSURE OVER THE SE
U.S. MOVES OUT OVER THE ATLANTIC WHILE RIDGING BACK TO THE WEST WITH
IT/S AXIS SETTLING SOUTHWARD OVER THE STATE THROUGH SAT. THE RIDGE
AXIS BEGINS TO SLIDE EAST SUN AS A FRONT SAGS IN OVER THE GULF COAST
AND SE U.S. THEN ON MON...THE GFS MOVES THE FRONT INTO THE STATE AND
WEAKENS IT WHILE THE ECMWF KEEPS A MORE ROBUST FRONT OVER OR JUST
NORTH OF FL.
THE FORECAST BEGINS DRY WITH TEMPERATURES JUST BELOW TO AROUND
NORMAL WITH NORTHEASTERLY WINDS. DURING THE WEEKEND WINDS BECOME
MORE EASTERLY AND SOUTHEASTERLY...ALLOWING TEMPERATURES TO WARM TO
ABOVE NORMAL AND PROVIDING INCREASING MOISTURE...WHICH ALONG WITH
THE APPROACHING FRONT...WILL RESULT IN SLIGHT CHANCE TO LOW END
CHANCE SHOWERS FOR SAT-MON.
&&
.AVIATION...
PREVAILING IFR/LCL LIFR IN DENSE BR/FG WITH VERY LOW STRATUS UNTIL
14-16Z. AFTER THAT VFR UNTIL 00Z WHEN MVFR CIGS MOVE IN...WITH VCSH
FOR NORTHERN TERMINALS AND LIMITED BR FOR THE SOUTHERN ONES. CALM TO
LIGHT AND VARIABLE WINDS BECOME SOUTHERLY LATE MORNING THEN SW IN
THE AFTERNOON.
&&
.MARINE...
AREAS OF DENSE SEA FOG WILL REMAIN A CONCERN THROUGH AT LEAST THE
MORNING HOURS...AND WILL LIKELY REMAIN IN THE FORECAST UNTIL A COLD
FRONT CLEARS THE REGION TONIGHT. AHEAD OF THIS FRONT LOOK FOR LIGHT
WINDS AND SEAS THROUGH THE DAY. WINDS SHIFT TO THE NORTH AND QUICKLY
INCREASE TO ADVISORY LEVELS IN THE WAKE OF THE FRONT AS IT MOVES
SLOWLY NORTH TO SOUTH ACROSS THE EASTERN GULF TONIGHT. ADVISORY
LEVEL WINDS AND SEAS AND HAZARDOUS BOATING CONDITIONS WILL LINGER
THROUGH WEDNESDAY BEFORE BEGINNING TO DIMINISH ON THURSDAY. A PERIOD
OF GENERALLY LIGHT WINDS AND LOW SEAS IS THEN ANTICIPATED FOR THE
END OF THE WEEK.
&&
.FIRE WEATHER...
A MOIST LOW LEVEL ENVIRONMENT WILL PREVENT ANY CRITICAL LEVELS OF
RELATIVE HUMIDITY TODAY. A COLD FRONT WILL CROSS THE REGION
TONIGHT...HOWEVER UNLIKE MOST COLD FRONTS...THE BULK OF THE SHOWER
ACTIVITY WILL BE POST FRONTAL WITH SHOWERS IN THE FORECAST THROUGH
WEDNESDAY AND INTO WEDNESDAY NIGHT. WEDNESDAY LOOKS LIKE A
CLOUDY...COOL...AND SHOWERY DAY WITH LOW MIXING HEIGHTS AND
RESULTING LDSI VALUES.
FOG POTENTIAL...WIDESPREAD FOG...SOME OF IT DENSE THIS MORNING.
AREAS OF FOG SHOULD BE CONFINED TO NEAR THE COAST FOR THE LATE
MORNING AND AFTERNOON HOURS. FOG MAY ONCE AGAIN EXPAND INLAND
AFTER SUNSET THIS EVENING MAINLY TO THE SOUTH OF THE I-4
CORRIDOR...AND THEN END WITH THE PASSAGE OF A COLD FRONT AFTER
MIDNIGHT.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 74 51 56 41 / 10 40 70 60
FMY 79 63 66 52 / 10 10 50 60
GIF 78 52 58 41 / 10 30 70 60
SRQ 73 56 61 47 / 10 30 60 60
BKV 74 46 53 39 / 20 50 70 60
SPG 72 51 58 45 / 10 40 70 60
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...DENSE FOG ADVISORY UNTIL 9 AM EST THIS MORNING FOR COASTAL
CHARLOTTE-COASTAL CITRUS-COASTAL HERNANDO-COASTAL
HILLSBOROUGH-COASTAL LEE-COASTAL LEVY-COASTAL MANATEE-
COASTAL PASCO-COASTAL SARASOTA-DESOTO-HARDEE-
HIGHLANDS-INLAND CHARLOTTE-INLAND CITRUS-INLAND
HERNANDO-INLAND HILLSBOROUGH-INLAND LEE-INLAND LEVY-
INLAND MANATEE-INLAND PASCO-INLAND SARASOTA-PINELLAS-
POLK-SUMTER.
GULF WATERS...DENSE FOG ADVISORY UNTIL 1 PM EST THIS AFTERNOON
FOR BONITA BEACH TO ENGLEWOOD OUT 20 NM-CHARLOTTE HARBOR
AND PINE ISLAND SOUND-ENGLEWOOD TO TARPON SPRINGS OUT
20 NM-TAMPA BAY WATERS-TARPON SPRINGS TO SUWANNEE
RIVER OUT 20 NM-TARPON SPRINGS TO SUWANNEE RIVER OUT
20 TO 60 NM.
&&
$$
SYNOPSIS/SHORT TERM/MARINE/FIRE WX...MROCZKA
LONG TERM/AVIATION...RUDE
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
913 PM EST WED JAN 29 2014
.SYNOPSIS...
ARCTIC HIGH PRESSURE WILL GRADUALLY BUILD INTO THE AREA FROM THE
WEST THROUGH TONIGHT...WHILE LOW PRESSURE OFFSHORE PULLS AWAY TO
THE NORTHEAST. ANOTHER WAVE OF LOW PRESSURE WILL LIFT NORTHEAST
ALONG THE STALLED FRONT WELL OFFSHORE THURSDAY...AS HIGH PRESSURE
BUILDS INLAND OVER THE SOUTHEAST STATES THROUGH FRIDAY. THE HIGH
WILL SLIDE INTO THE ATLANTIC DURING THE WEEKEND AND EXTEND ACROSS
THE AREA INTO EARLY NEXT WEEK. THE NEXT COLD FRONT COULD IMPACT
THE REGION BY TUESDAY.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
LATEST WATER VAPOR SATELLITE IMAGERY INDICATES A FAST MOVING BUT
DISORGANIZED SHORT WAVE SHIFTING THROUGH THE NORTHERN GULF COAST
REGION THIS EVENING. A STRIPE OF ELONGATED UPPER DIFLUENCE IS PASSING
OVER THE FORECAST AREA THIS EVENING...MAINTAINING THE SHIELD OF
ALTOSTRATUS. LATEST RAP FORECAST SOUNDINGS FOR SE GEORGIA TO THE
SOUTH OF I-16 INDICATE THE VERY DRY LAYER BETWEEN 2 KFT AND 9 KFT
WILL MOISTEN UP...BUT NOT SIGNIFICANTLY OVER THE NEXT SEVERAL
HOURS. UNTIL THIS EVENING IMPULSE HAS PASSED WE WERE NOT
COMFORTABLE LOWERING ONGOING WINTER STORM WARNINGS FOR PORTIONS OF
SE GEORGIA. WE THINK ADDITIONAL LIGHT FREEZING RAIN IS POSSIBLE
FOR SEVERAL MORE HOURS IN THE WARNING AREA AND EXTENDED THE WINTER
STORM WARNINGS FOR COASTAL SE GEORGIA UNTIL 5 AM. WHEN THE RISK
FOR ADDITIONAL MEASURABLE FREEZING PRECIP ENDS OVERNIGHT...AN
EARLIER CANCELLATION MAY OCCUR.
THE NEXT MAJOR CHALLENGE DURING THE LATE NIGHT PERIOD IS THE
POTENTIAL FOR LIGHT FREEZING DRIZZLE DEVELOPING ALONG IMMEDIATE
COASTAL AREAS. AS ISENTROPIC ASCENT ON 290K SURFACE BUILDS FROM
THE ATLC AHEAD OF A SECOND UPPER DISTURBANCE IN THE STRONG SW FLOW
ALOFT...THERE COULD BE ENOUGH OMEGA WITH THE UPPER SHORT WAVE TO
SUPPORT FREEZING DRIZZLE OR LIGHT FREEZING RAIN LATE TONIGHT ALONG
THE SC/GA COAST. WE MAINTAINED MENTIONS OF FREEZING RAIN/DRIZZLE
TO OUR COASTAL AREAS LATE BUT DID NOT INCLUDE ANY ICE
ACCUMULATIONS AT THIS TIME. WILL CONTINUE TO MONITOR TRENDS TO
DETERMINE IF THIS PRECIP ACTUALLY DEVELOPS AND AFFECTS LAND
AREAS...AT WHICH POINT A WINTER WEATHER ADVISORY MAY BE NEEDED DUE
TO FRESH ACCUMULATIONS.
FINALLY...DUE TO THE COLD TEMPERATURES OVERNIGHT...ROADS AND
BRIDGES WILL LIKELY BECOME QUITE TREACHEROUS AS WATER AND SLUSH
REFREEZES. SOME BRIDGES THAT HAVE BEEN ALLOWING TRAFFIC TODAY
COULD BE AT A HEIGHTENED RISK FOR DANGEROUS BLACK ICE PATCHES IF
RESIDUAL WATER PATCHES FREEZES OVERNIGHT. WE HAVE A SPECIAL
WEATHER STATEMENT IN EFFECT THAT ADDRESSES THE REFREEZING
POTENTIAL.
OTHERWISE...ONLY MINOR TWEAKS TO TEMPS AND CLOUD COVER OVERNIGHT
RECENT TRENDS DICTATE.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY/...
THURSDAY...SHORTWAVE ENERGY WILL CONTINUE TO TRACK ACROSS THE
GULF OF MEXICO AND UP TO THE SOUTHEAST STATES...AND WHEN COMBINED
WITH FORCING FROM THE RIGHT ENTRANCE REGION OF AN UPPER JET...WILL
DEVELOP ANOTHER WAVE OF LOW PRESSURE ALONG THE OFFSHORE BAROCLINIC
ZONE. THE TRACK AND STRENGTH OF THIS WAVE WILL DETERMINE THE
PROXIMITY WITH WHICH AN ASSOCIATED RIBBON OF DEEP MOISTURE AND
AREA OF OVERRUNNING PRECIPITATION CAN MEANDER BACK TOWARD THE
COASTLINE. NUMERICAL MODEL SOLUTIONS SUGGEST THAT LIGHT
PRECIPITATION COULD LINGER THROUGH THE EARLY AFTERNOON...
ESPECIALLY NEAR THE BEACHES AND THE FAR SOUTHEAST GEORGIA
COASTLINE. TEMPERATURES WILL REMAIN BELOW FREEZING UNTIL AROUND 10
TO 11 AM...AND THUS ANY LIGHT PRECIPITATION WILL BE IN THE FORM OF
FREEZING DRIZZLE TO FREEZING RAIN. DUE TO THE ISOLATED AND LIGHT
NATURE OF ANY PRECIPITATION...THERE IS NO MEASURABLE ICE
ACCUMULATION EXPECTED AT THIS POINT. THE MAJORITY OF THE FORECAST
AREA WILL ACTUALLY REMAIN DRY THROUGH THURSDAY NIGHT. PARTLY TO
MOSTLY CLOUDY SKIES WILL PREVAIL UNTIL EARLY AFTERNOON...BEFORE
SCATTERING FROM WEST TO EAST OCCURS LATER IN THE DAY. HIGH
TEMPERATURES WILL REBOUND NEARLY 10 DEGREES...REACHING THE LOW TO
MID 40S BY MID AFTERNOON. LOW TEMPERATURES WILL STILL BE QUITE
COLD WHILE STILL REFLECTING THE MODERATING TREND...RANGING FROM
THE LOW 20S INLAND TO THE LOW 30S NEAR THE COAST.
FRIDAY...SURFACE HIGH PRESSURE WILL TRACK OVER THE FORECAST AREA
DURING THE DAYTIME HOURS AND OFF THE COAST OVERNIGHT...WHILE
HEIGHTS ALOFT SLOWLY INCREASE. THIS TRANSITION WILL CONTINUE THE
WARMING TREND ACROSS THE REGION...WITH HIGH TEMPERATURES IN THE
50S AND NIGHTTIME LOW TEMPERATURES IN THE UPPER 30S TO MID 40S.
THERE IS EVIDENCE IN NUMERICAL MODEL SOLUTIONS THAT A SUBTLE
COASTAL TROUGH OR WAVE OF LOW PRESSURE COULD BE DEVELOPING ALONG
THE PERIPHERY OF THE SURFACE HIGH AT THIS TIME. THE INCREASE IN
CONVERGENCE COULD SUPPORT ISOLATED SHOWERS OVER THE ATLANTIC
WATERS...YET THE TROUGH WILL LIKELY REMAIN FAR ENOUGH OFFSHORE TO
KEEP RAIN CHANCES BELOW 15 PERCENT FOR LAND AREAS.
SATURDAY...AS THE SURFACE HIGH SETTLES INTO THE NEARBY ATLANTIC
WATERS...RETURN FLOW AROUND THE FEATURE WILL SUPPORT AN INCREASE
IN LOW LEVEL MOISTURE. TEMPERATURES WILL STEADILY RISE INTO THE
LOW 60S NORTHWEST TO UPPER 60S SOUTHEAST...AND WHEN COMBINED WITH
THE INCREASE IN DEWPOINTS...THESE WARMER TEMPERATURES COULD
SUPPORT ISOLATED SHOWERS DURING THE AFTERNOON. WILL THUS MAINTAIN
15 TO 20 PERCENT RAIN CHANCES ON SATURDAY.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
SATURDAY NIGHT THROUGH MONDAY...A DAMPENED PATTERN WILL PREVAIL
ALOFT...WITH A STRONG ANTICYCLONE CENTERED OVER THE FLORIDA
STRAITS AND BAHAMAS...WHILE A SPLIT FLOW FORMS OUT WEST. THE
FORECAST AREA WILL BE SITUATED WITHIN A MAINLY ZONAL FLOW NORTH
OF THE RIDGE...WHILE A COASTAL TROUGH FALLS APART AND ATLANTIC
HIGH PRESSURE EXTENDS ACROSS THE AREA. A SOUTH AND SW FLOW AROUND
THE SURFACE HIGH WILL ALLOW FOR A CONTINUED INCREASED IN LOW LEVEL
MOISTURE. HIGHER MOISTURE LEVELS COMBINED WITH STRONGER WIND
FIELDS IN THE MID/UPPER LEVELS WILL SUPPORT 20 TO 30 PERCENT RAIN
CHANCES. WARM ADVECTION IS QUITE SUBSTANTIAL AND TEMPERATURES
COULD REACH 70 DEGREES IN SOME PLACES AWAY FROM THE BEACHES
EARLY NEXT WEEK. ONE LOW-END CAVEAT TO THE FORECAST WILL BE THE
RISK FOR SEA FOG...AS THE WARMER AND EVENTUALLY MORE HUMID AIR
OVERRIDES THE COOLER NEARSHORE WATERS.
MONDAY NIGHT THROUGH WEDNESDAY...TIMING IS SLOWER THAN SEEN IN
PREVIOUS MODEL RUNS REGARDING THE NEXT COLD FRONT...WITH THE
ACTUAL FRONTAL PASSAGE POTENTIALLY OCCURRING BY TUESDAY. ISOLATED
TO SCATTERED SHOWERS WILL OCCUR IN ADVANCE OF THE FRONT...WITH
COOLER HIGH PRESSURE TO BUILD IN ITS WAKE.
&&
.AVIATION /02Z THURSDAY THROUGH MONDAY/...
KCHS...FORECAST SOUNDINGS OVERNIGHT SUGGEST VFR CONDITIONS WILL
PREVAIL WITH SOME LOWERING CLOUDS 4-8 KFT LIKELY LATE. THERE COULD
BE A BIT OF VERY LIGHT FREEZING DRIZZLE AT SOME POINT THURSDAY
MORNING BUT CONFIDENCE REMAINS QUITE LOW. STRATOCUMULUS FIELDS
ARE EXPECTED TO INCREASE THURSDAY AND THERE COULD BE MVFR CIGS
DEVELOPING LATER IN THE DAY. AT THIS POINT...TIMING AND AREAL
EXTENT TO QUESTIONABLE TO INCLUDE IN THE LATTER PART OF THE 00Z
TAF CYCLE.
KSAV...CANNOT RULE OUT PATCHY FREEZING DRIZZLE OVERNIGHT BUT
IT APPEARS CHANCES FOR MEASURABLE FREEZING PRECIP IS FAIRLY LOW
GIVEN LATEST TRENDS. MAINLY VFR OVERNIGHT WITH THICKER MID LEVEL
CLOUDS MORE LIKELY. MODELS DIFFER ON POTENTIAL FOR MVFR CIGS DURING
THURSDAY AND FOR NOW WE HAVE TRENDED VFR BUT MVFR CIGS COULD REDEVELOP
BY MID/LATE AFTERNOON.
EXTENDED AVIATION OUTLOOK...MODERATE PROBABILITIES OF SUB-VFR
CONDITIONS DURING THE WEEKEND...OTHERWISE VFR WEATHER WILL PREVAIL.
&&
.MARINE...
OVERNIGHT AND THURSDAY...WILL MAINTAIN MARGINAL SMALL CRAFT ADVISORIES
ACROSS THE NEARSHORE WATERS THROUGH THURSDAY...WITH SLIGHTLY HIGHER
CONFIDENCE THAT ADVISORY CRITERIA IS BEING REACHED IN THE OFFSHORE
ZONES. CONSIDERING THE ENHANCED PRESSURE GRADIENT BETWEEN A
DEPARTING ATLANTIC WAVE AND BUILDING HIGH PRESSURE INLAND...GUSTS
TO 25 KT AND SEAS NEAR 6 FT COULD BE OCCURRING...MAINLY BEYOND 10
TO 15 NM. THIS TIGHT GRADIENT IS EXPECTED TO REMAIN OVER THE
MARINE ZONES THROUGH EARLY THURSDAY....ALTHOUGH HIGHLY DEPENDENT
ON THE ORIENTATION OF THE PREDOMINANT SURFACE FEATURES. THE
GRADIENT WILL EVENTUALLY WEAKEN AS THE CENTER OF THE SURFACE HIGH
SETTLES OVER THE REGION LATER THURSDAY...WHILE A SECONDARY WAVE OF
LOW PRESSURE DEVELOPS ALONG THE LINGERING BAROCLINIC ZONE WELL OFF
THE SOUTHEAST AND FLORIDA COASTLINE.
THURSDAY NIGHT THROUGH SUNDAY...WIND AND SEA CONDITIONS WILL BE
VASTLY IMPROVED DURING THIS TIME...WITH THE LOCAL WATERS GENERALLY
INFLUENCED BY HIGH PRESSURE THAT SHIFTS INTO THE ATLANTIC. AN
INVERTED TROUGH WILL LIKELY FORM OVER OR NEARBY THE MARINE
ZONES...PREVENTING WINDS FROM VEERING TOO QUICKLY. HOWEVER...ONCE
WINDS CLOCK AROUND TO A MORE SOUTHERLY DIRECTION SUNDAY...THERE IS
A LOW END RISK FOR SEA FOG DEVELOPMENT.
MONDAY...THE NEXT COLD FRONT WILL APPROACH...BUT TIMING OF THE
ACTUAL PASSAGE IS STILL IN QUESTION THIS FAR IN ADVANCE...WITH
BLOCKING HIGH PRESSURE IN PLACE OUT AHEAD OF IT.
&&
.TIDES/COASTAL FLOODING...
TIDES WILL REMAIN ELEVATED THROUGH LATE THIS WEEK GIVEN THE
PERIGEAN SPRING TIDES...SUGGESTING THAT SHALLOW COASTAL FLOODING
COULD OCCUR WITH THE MORNING HIGH TIDE ALONG THE CHARLESTON COUNTY
COAST.
&&
.CLIMATE...
A RECORD LOW MAXIMUM TEMPERATURE READING AT CHARLESTON TODAY...32
DEGREES. DOWNTOWN CHARLESTON MAY ALSO HAVE TIED OR BROKEN THEIR
LOW MAX RECORD. DETAILS AVAILABLE ON THE OVERNIGHT CLIMATE REPORT.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...WINTER STORM WARNING UNTIL 5 AM EST THURSDAY FOR GAZ116>119-
137>141.
SC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 1 PM EST THURSDAY FOR AMZ350-352-
354.
SMALL CRAFT ADVISORY UNTIL 11 PM EST THURSDAY FOR AMZ374.
&&
$$
SYNOPSIS...
NEAR TERM...
SHORT TERM...WMS
LONG TERM...33/WMS
AVIATION...
MARINE...
TIDES/COASTAL FLOODING...
CLIMATE...
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
647 PM EST WED JAN 29 2014
.SYNOPSIS...
ARCTIC HIGH PRESSURE WILL GRADUALLY BUILD INTO THE AREA FROM THE
WEST THROUGH TONIGHT...WHILE LOW PRESSURE OFFSHORE PULLS AWAY TO
THE NORTHEAST. ANOTHER WAVE OF LOW PRESSURE WILL LIFT NORTHEAST
ALONG THE STALLED FRONT WELL OFFSHORE THURSDAY...AS HIGH PRESSURE
BUILDS INLAND OVER THE SOUTHEAST STATES THROUGH FRIDAY. THE HIGH
WILL SLIDE INTO THE ATLANTIC DURING THE WEEKEND AND EXTEND ACROSS
THE AREA INTO EARLY NEXT WEEK. THE NEXT COLD FRONT COULD IMPACT
THE REGION BY TUESDAY.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
ALTHOUGH THE BRUNT OF THE WINTER STORM HAS ENDED...WE ARE STILL
FACED WITH LINGERING CHALLENGES THROUGH THE OVERNIGHT HOURS. THE
SURFACE FRONT REMAINS STALLED JUST OFF THE COAST WITH COLD AND DRY
ARCTIC HIGH PRESSURE CONTINUING TO BUILD EAST AND SOUTH INTO THE
SOUTHEAST UNITED STATES. TEMPERATURES HAVE MOVED VERY LITTLE TODAY
DUE TO EXTENSIVE LOW OVERCAST AND CONSTANTLY REFRESHED COLD AIR
VIA A NORTHERLY BOUNDARY LAYER FLOW. TEMPERATURES HAVE REMAINED AT
OR BELOW FREEZING ACROSS THE FORECAST AREA AND WILL ARE EXPECTED
TO SLOWLY FALL OVERNIGHT DESPITE THE PERSISTENT CLOUD COVER.
THE FIRST ISSUE WE HAVE BEEN BATTLING IS THE PERSISTENT LIGHT
PRECIPITATION ACROSS FAR SOUTHERN GA. AN UPPER DISTURBANCE MOVING
ALONG THE GULF COAST REGION TOWARD GA/SC HAS BEEN MAINTAINING A
WEAK SURFACE TROUGH AND LOW-LEVEL WARM ADVECTION ABOVE THE COOL
BOUNDARY LAYER IN NORTHERN FL AND SOUTHERN GA. THIS HAS ALLOWED
FOR LIGHT FREEZING RAIN TO CONTINUE ACROSS OUR FAR SOUTHERN GA
ZONES FOR MUCH OF THE AFTERNOON. WE HAVE ONLY RECEIVED SPORADIC
REPORTS FROM THOSE AREAS SINCE MANY OF THE UPSTREAM AUTOMATED OB
SITES HAVE NOT BEEN CARRYING PRESENT WX. A RECENT REPORT OF
LIGHT FREEZING RAIN AROUND JESUP GA SUGGESTS RADAR RETURNS IN SOME
SPOTS TO THE SOUTH OF I-16 COULD STILL BE PRODUCING LOCAL LIGHT
FREEZING RAIN. WE MAINTAINED THE WINTER STORM WARNING FOR OUR
COASTAL SOUTHEAST GA ZONES UNTIL 9 PM TO ADDRESS SOME ADDITIONAL
LIGHT ICE ACCUMULATIONS.
THE NEXT MAJOR CHALLENGE DURING THIS FORECAST PERIOD IS THE
POTENTIAL FOR LIGHT FREEZING RAIN LATE TONIGHT ALONG THE SC/GA
COAST. THE AFOREMENTIONED UPPER SHORTWAVE WILL SHIFT ENE TO A
POSITION OFF THE GA COAST BY DAYBREAK THURSDAY. ALOFT A 250 MB JET
STREAK WILL REMAIN OFF THE MID-ATLANTIC COAST WITH MODERATE UPPER
LEVEL DIVERGENCE ACROSS THE SOUTHEAST UNITED STATES. ANOTHER WAVE
OF LOW PRESSURE IS EXPECTED TO DEVELOP ALONG THE STALLED FRONT OFF
THE FL COAST AND EVENTUALLY LIFT NORTHEAST ON THURSDAY. THE
CONCERN IS A SHARP BACKING IN THE 900-800 MB LAYER AFTER 06Z WITH
SSW FETCH DEVELOPING. THIS WILL ALLOW FOR WEAK OVERRUNNING AND
SATURATION IN THIS LAYER. THERE COULD BE ENOUGH OMEGA TO SUPPORT
FREEZING DRIZZLE OR LIGHT FREEZING RAIN LATE TONIGHT ALONG THE
SC/GA COAST. THE POTENTIAL FOR SNOW IS QUITE LOW DUE TO A LACK OF
APPRECIABLE MOISTURE IN THE DENDRITIC GROWTH ZONE /-10 TO -20C/.
SLEET IS ALSO NOT TERRIBLY LIKELY SINCE THE UPWARD VERTICAL
VELOCITIES WILL BE SO LIMITED. WE ADDED MENTION OF FREEZING
RAIN/DRIZZLE TO OUR COASTAL AREAS LATE TONIGHT BUT DID NOT INCLUDE
ANY ICE ACCUMULATIONS AT THIS TIME. LATER SHIFTS WILL NEED TO
MONITOR TRENDS TO DETERMINE IF THIS PRECIP ACTUALLY DEVELOPS AND
AFFECTS LAND AREAS...AT WHICH POINT A WINTER WEATHER ADVISORY MAY
BE NEEDED DUE TO FRESH ACCUMULATIONS.
SKY COVER WILL DIMINISH FAR INLAND WHICH MAY ALLOW FOR MARGINAL
RADIATIONAL COOLING THOUGH WINDS WILL PROBABLY NOT DECOUPLE.
COLD ADVECTION WITH THE ARCTIC HIGH BUILDING INTO PLACE AND SOME
LINGERING ICE/SNOW AT THE SURFACE WILL MAKE FOR A COLD NIGHT. FAR
INLAND TEMPS WILL BE IN THE TEENS BY DAYBREAK WHILE THE REST OF
THE AREA IS IN THE LOWER TO MIDDLE 20S.
FINALLY...DUE TO THE COLD TEMPERATURES OVERNIGHT...ROADS AND
BRIDGES WILL LIKELY BECOME QUITE TREACHEROUS AS WATER AND SLUSH
REFREEZES. SOME BRIDGES THAT HAVE BEEN ALLOWING TRAFFIC TODAY
COULD BE AT A HEIGHTENED RISK FOR DANGEROUS BLACK ICE PATCHES IF
RESIDUAL WATER PATCHES FREEZES OVERNIGHT. WE HAVE A SPECIAL
WEATHER STATEMENT IN EFFECT THAT ADDRESSES THE REFREEZING
POTENTIAL.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY/...
THURSDAY...SHORTWAVE ENERGY WILL CONTINUE TO TRACK ACROSS THE
GULF OF MEXICO AND UP TO THE SOUTHEAST STATES...AND WHEN COMBINED
WITH FORCING FROM THE RIGHT ENTRANCE REGION OF AN UPPER JET...WILL
DEVELOP ANOTHER WAVE OF LOW PRESSURE ALONG THE OFFSHORE BAROCLINIC
ZONE. THE TRACK AND STRENGTH OF THIS WAVE WILL DETERMINE THE
PROXIMITY WITH WHICH AN ASSOCIATED RIBBON OF DEEP MOISTURE AND
AREA OF OVERRUNNING PRECIPITATION CAN MEANDER BACK TOWARD THE
COASTLINE. NUMERICAL MODEL SOLUTIONS SUGGEST THAT LIGHT
PRECIPITATION COULD LINGER THROUGH THE EARLY AFTERNOON...
ESPECIALLY NEAR THE BEACHES AND THE FAR SOUTHEAST GEORGIA
COASTLINE. TEMPERATURES WILL REMAIN BELOW FREEZING UNTIL AROUND 10
TO 11 AM...AND THUS ANY LIGHT PRECIPITATION WILL BE IN THE FORM OF
FREEZING DRIZZLE TO FREEZING RAIN. DUE TO THE ISOLATED AND LIGHT
NATURE OF ANY PRECIPITATION...THERE IS NO MEASURABLE ICE
ACCUMULATION EXPECTED AT THIS POINT. THE MAJORITY OF THE FORECAST
AREA WILL ACTUALLY REMAIN DRY THROUGH THURSDAY NIGHT. PARTLY TO
MOSTLY CLOUDY SKIES WILL PREVAIL UNTIL EARLY AFTERNOON...BEFORE
SCATTERING FROM WEST TO EAST OCCURS LATER IN THE DAY. HIGH
TEMPERATURES WILL REBOUND NEARLY 10 DEGREES...REACHING THE LOW TO
MID 40S BY MID AFTERNOON. LOW TEMPERATURES WILL STILL BE QUITE
COLD WHILE STILL REFLECTING THE MODERATING TREND...RANGING FROM
THE LOW 20S INLAND TO THE LOW 30S NEAR THE COAST.
FRIDAY...SURFACE HIGH PRESSURE WILL TRACK OVER THE FORECAST AREA
DURING THE DAYTIME HOURS AND OFF THE COAST OVERNIGHT...WHILE
HEIGHTS ALOFT SLOWLY INCREASE. THIS TRANSITION WILL CONTINUE THE
WARMING TREND ACROSS THE REGION...WITH HIGH TEMPERATURES IN THE
50S AND NIGHTTIME LOW TEMPERATURES IN THE UPPER 30S TO MID 40S.
THERE IS EVIDENCE IN NUMERICAL MODEL SOLUTIONS THAT A SUBTLE
COASTAL TROUGH OR WAVE OF LOW PRESSURE COULD BE DEVELOPING ALONG
THE PERIPHERY OF THE SURFACE HIGH AT THIS TIME. THE INCREASE IN
CONVERGENCE COULD SUPPORT ISOLATED SHOWERS OVER THE ATLANTIC
WATERS...YET THE TROUGH WILL LIKELY REMAIN FAR ENOUGH OFFSHORE TO
KEEP RAIN CHANCES BELOW 15 PERCENT FOR LAND AREAS.
SATURDAY...AS THE SURFACE HIGH SETTLES INTO THE NEARBY ATLANTIC
WATERS...RETURN FLOW AROUND THE FEATURE WILL SUPPORT AN INCREASE
IN LOW LEVEL MOISTURE. TEMPERATURES WILL STEADILY RISE INTO THE
LOW 60S NORTHWEST TO UPPER 60S SOUTHEAST...AND WHEN COMBINED WITH
THE INCREASE IN DEWPOINTS...THESE WARMER TEMPERATURES COULD
SUPPORT ISOLATED SHOWERS DURING THE AFTERNOON. WILL THUS MAINTAIN
15 TO 20 PERCENT RAIN CHANCES ON SATURDAY.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
SATURDAY NIGHT THROUGH MONDAY...A DAMPENED PATTERN WILL PREVAIL
ALOFT...WITH A STRONG ANTICYCLONE CENTERED OVER THE FLORIDA
STRAITS AND BAHAMAS...WHILE A SPLIT FLOW FORMS OUT WEST. THE
FORECAST AREA WILL BE SITUATED WITHIN A MAINLY ZONAL FLOW NORTH
OF THE RIDGE...WHILE A COASTAL TROUGH FALLS APART AND ATLANTIC
HIGH PRESSURE EXTENDS ACROSS THE AREA. A SOUTH AND SW FLOW AROUND
THE SURFACE HIGH WILL ALLOW FOR A CONTINUED INCREASED IN LOW LEVEL
MOISTURE. HIGHER MOISTURE LEVELS COMBINED WITH STRONGER WIND
FIELDS IN THE MID/UPPER LEVELS WILL SUPPORT 20 TO 30 PERCENT RAIN
CHANCES. WARM ADVECTION IS QUITE SUBSTANTIAL AND TEMPERATURES
COULD REACH 70 DEGREES IN SOME PLACES AWAY FROM THE BEACHES
EARLY NEXT WEEK. ONE LOW-END CAVEAT TO THE FORECAST WILL BE THE
RISK FOR SEA FOG...AS THE WARMER AND EVENTUALLY MORE HUMID AIR
OVERRIDES THE COOLER NEARSHORE WATERS.
MONDAY NIGHT THROUGH WEDNESDAY...TIMING IS SLOWER THAN SEEN IN
PREVIOUS MODEL RUNS REGARDING THE NEXT COLD FRONT...WITH THE
ACTUAL FRONTAL PASSAGE POTENTIALLY OCCURRING BY TUESDAY. ISOLATED
TO SCATTERED SHOWERS WILL OCCUR IN ADVANCE OF THE FRONT...WITH
COOLER HIGH PRESSURE TO BUILD IN ITS WAKE.
&&
.AVIATION /00Z THURSDAY THROUGH MONDAY/...
KCHS...FORECAST SOUNDINGS OVERNIGHT SUGGEST VFR CONDITIONS WILL
PREVAIL WITH SOME LOWERING CLOUDS 4-8 KFT LIKELY LATE. THERE COULD
BE A BIT OF VERY LIGHT FREEZING DRIZZLE AT SOME POINT THURSDAY
MORNING BUT CONFIDENCE REMAINS QUITE LOW. STRATOCUMULUS FIELDS
ARE EXPECTED TO INCREASE THURSDAY AND THERE COULD BE MVFR CIGS
DEVELOPING LATER IN THE DAY. AT THIS POINT...TIMING AND AREAL
EXTENT TO QUESTIONABLE TO INCLUDE IN THE LATTER PART OF THE 00Z
TAF CYCLE.
KSAV...CANNOT RULE OUT PATCHY FREEZING DRIZZLE OVERNIGHT BUT
IT APPEARS CHANCES FOR MEASURABLE FREEZING PRECIP IS FAIRLY LOW
GIVEN LATEST TRENDS. MVFR CIGS SHOULD BEGIN TO BREAK UP BY MID
EVENING PER LATEST FORECAST SOUNDINGS FROM THE RAP AND NAM MODELS.
MODELS DIFFER ON POTENTIAL FOR MVFR CIGS ON THURSDAY AND FOR NOW
WE HAVE TRENDED VFR BUT MVFR CIGS MAY REDEVELOP BY MID/LATE
AFTERNOON.
EXTENDED AVIATION OUTLOOK...MODERATE PROBABILITIES OF SUB-VFR
CONDITIONS DURING THE WEEKEND...OTHERWISE VFR WEATHER WILL PREVAIL.
&&
.MARINE...
TONIGHT AND THURSDAY...WILL MAINTAIN MARGINAL SMALL CRAFT ADVISORIES
ACROSS THE NEARSHORE WATERS THROUGH THURSDAY...WITH SLIGHTLY HIGHER
CONFIDENCE THAT ADVISORY CRITERIA IS BEING REACHED IN THE OFFSHORE
ZONES. CONSIDERING THE ENHANCED PRESSURE GRADIENT BETWEEN A
DEPARTING ATLANTIC WAVE AND BUILDING HIGH PRESSURE INLAND...GUSTS
TO 25 KT AND SEAS NEAR 6 FT COULD BE OCCURRING...MAINLY BEYOND 10
TO 15 NM. THIS TIGHT GRADIENT IS EXPECTED TO REMAIN OVER THE
MARINE ZONES THROUGH EARLY THURSDAY....ALTHOUGH HIGHLY DEPENDENT
ON THE ORIENTATION OF THE PREDOMINANT SURFACE FEATURES. THE
GRADIENT WILL EVENTUALLY WEAKEN AS THE CENTER OF THE SURFACE HIGH
SETTLES OVER THE REGION LATER THURSDAY...WHILE A SECONDARY WAVE OF
LOW PRESSURE DEVELOPS ALONG THE LINGERING BAROCLINIC ZONE WELL OFF
THE SOUTHEAST AND FLORIDA COASTLINE.
THURSDAY NIGHT THROUGH SUNDAY...WIND AND SEA CONDITIONS WILL BE
VASTLY IMPROVED DURING THIS TIME...WITH THE LOCAL WATERS GENERALLY
INFLUENCED BY HIGH PRESSURE THAT SHIFTS INTO THE ATLANTIC. AN
INVERTED TROUGH WILL LIKELY FORM OVER OR NEARBY THE MARINE
ZONES...PREVENTING WINDS FROM VEERING TOO QUICKLY. HOWEVER...ONCE
WINDS CLOCK AROUND TO A MORE SOUTHERLY DIRECTION SUNDAY...THERE IS
A LOW END RISK FOR SEA FOG DEVELOPMENT.
MONDAY...THE NEXT COLD FRONT WILL APPROACH...BUT TIMING OF THE
ACTUAL PASSAGE IS STILL IN QUESTION THIS FAR IN ADVANCE...WITH
BLOCKING HIGH PRESSURE IN PLACE OUT AHEAD OF IT.
&&
.TIDES/COASTAL FLOODING...
TIDES WILL REMAIN ELEVATED THROUGH LATE THIS WEEK GIVEN THE
PERIGEAN SPRING TIDES...SUGGESTING THAT SHALLOW COASTAL FLOODING
COULD OCCUR WITH THE MORNING HIGH TIDE ALONG THE CHARLESTON COUNTY
COAST.
&&
.CLIMATE...
RECORD LOW MAX TEMPS FOR JANUARY 29TH...
KCHS...41 SET IN 2000.
KCHL...36 SET IN 1897.
KSAV...33 SET IN 1897.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...WINTER STORM WARNING UNTIL 9 PM EST THIS EVENING FOR
GAZ116>119-137>141.
SC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 1 PM EST THURSDAY FOR AMZ350-352-
354.
SMALL CRAFT ADVISORY UNTIL 11 PM EST THURSDAY FOR AMZ374.
&&
$$
SYNOPSIS...
NEAR TERM...
SHORT TERM...WMS
LONG TERM...33/WMS
AVIATION...
MARINE...33/WMS
TIDES/COASTAL FLOODING...
CLIMATE...
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
526 PM EST TUE JAN 28 2014
.SYNOPSIS...
ARCTIC HIGH PRESSURE WILL GRADUALLY BUILD INTO THE AREA FROM THE
NORTH AND WEST THROUGH TONIGHT WHILE WAVES OF LOW PRESSURE MOVE UP
THE COAST. HIGH PRESSURE WILL THEN BUILD INTO THE REGION
WEDNESDAY AND PREVAIL INTO THE WEEKEND. ANOTHER COLD FRONT WILL
MOVE THROUGH THE REGION BY EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
THE WINTER STORM IS RAPIDLY RAMPING UP LATE THIS AFTERNOON. AN
INVERTED SURFACE TROUGH FROM SOUTHEAST GA UP INTO THE SC UPSTATE
FOR MUCH OF THE DAY WAS MAINTAINING A WARM TONGUE IN ALL BUT OUR
FAR NORTHERN ZONES. THIS TROUGH HAS QUICKLY DISSIPATED DURING THE
AFTERNOON HOURS NOW THAT THE SURFACE LOW IS DEVELOPING OFF THE SC
COAST. EXTENSIVE PRECIP HAS MOVED INTO THE AREA WHICH IS PRODUCING
RAPID EVAPORATIONAL COOLING AND ALLOWING MOST AREA TEMPS TO DROP
INTO THE LOWER TO MIDDLE 30S. THE ARCTIC SURFACE HIGH OVER THE
CENTRAL UNITED STATES WILL STRENGTHEN OVERNIGHT AS THE UPPER
TROUGH DIGS INTO THE LOWER MISSISSIPPI VALLEY. WITH THE SUN GOING
DOWN AND THE INLAND SURFACE HIGH STRENGTHENING...TEMPS WILL DROP
TO OR BELOW FREEZING BY 7 PM IN SOUTHERN SC WITH INTERIOR
SOUTHEAST GA AT FREEZING LATER THIS EVENING.
WE HAVE BEEN RECEIVING NUMEROUS REPORTS OF SLEET AND FREEZING RAIN
MIXING WITH LIQUID RAIN SINCE THE MIDDLE OF THE AFTERNOON. OUR 18Z
SOUNDING CONFIRMED WHAT THE GUIDANCE HAS BEEN INDICATING FOR
SEVERAL DAYS...WITH A PRONOUNCED WARM NOSE ABOVE A 2000 FT DEEP
SUB-FREEZING BOUNDARY LAYER. RUC13 AND NAM12 MODEL SOUNDINGS SEEM
TO BE DOING FAIRLY WELL AT TRACKING THE THERMAL PROFILE THIS
AFTERNOON. THE CONSENSUS INDICATES THE PROFILE WILL TRANSITION TO
A FREEZING RAIN AND SLEET MIX THROUGH THE EVENING HOURS ACROSS
MUCH OF SOUTHEAST SC AND INLAND SOUTHEAST GA. FARTHER TO THE SOUTH
TOWARD COASTAL SOUTHEAST GA...RAIN WILL DOMINATE THROUGH EARLY
THIS EVENING WITH SLEET OCCASIONALLY MIXING IN. THEN THE SLEET AND
FREEZING RAIN WILL BECOME THE PREDOMINANT P-TYPES PRETTY MUCH
EVERYWHERE BY LATE THIS EVENING EXCEPT PERHAPS THE GA BEACHES.
THE HEAVIEST QPF WILL OCCUR THROUGH EARLY WEDNESDAY MORNING WHEN A
POTENT UPPER VORT LIFTS NORTHEAST...COINCIDENT WITH A POTENT UPPER
JET RIGHT ENTRANCE REGION AND THE DEEPEST MOISTURE. LATE THIS
EVENING THE THERMAL PROFILES ACROSS OUR INLAND TIER OF COUNTIES
COOL ENOUGH THROUGHOUT THE COLUMN TO SUPPORT MAINLY SNOW WITH SOME
SLEET. THIS TREND WILL TREK STEADILY TOWARD THE SOUTHEAST THROUGH
WEDNESDAY DAYBREAK. FOR MUCH OF THE NIGHT OUR COASTAL SOUTHEAST GA
ZONES WILL MAINLY EXPERIENCE FREEZING RAIN AND SOME SLEET...WITH
SNOW POSSIBLE CLOSE TO DAYBREAK.
AS FOR ACCUMULATIONS...IT IS OF COURSE VERY CHALLENGING TO PIN
DOWN AT ANY GIVEN LOCATION SINCE THE PRECIP WILL BE TRANSITIONING
CONSTANTLY. ALSO...SINCE A SIGNIFICANT AMOUNT OF THE QPF MAY FALL
AS SLEET RATHER THAN SNOW...THIS DECREASES THE LIQUID TO SOLID
CONVERSION RATIO. OUR LATEST FORECAST IS FAIRLY SIMILAR TO THE
PREVIOUS PACKAGE WITH THE HIGHEST AMOUNTS BEING 2-3 INCHES OF
SLEET/SNOW ACROSS SOUTHERN SC...ALONG WITH THE GREATER ICE
ACCRETION UP TO HALF AN INCH. ELSEWHERE THE TOTALS WILL DIMINISH
AS ONE MOVES SOUTH AND WEST...HOWEVER SIGNIFICANT ACCUMULATIONS
WILL STILL OCCUR. NO CHANGES WERE MADE TO THE WINTER STORM WARNING
IN EFFECT FOR ALL AREAS. IT IS UNCLEAR IF WE WILL REACH WARNING
CRITERIA ICE OR SNOW/SLEET ACROSS FAR SOUTHEAST GA. HOWEVER TRAVEL
WILL CERTAINLY BE HAMPERED AND EVERYONE IN THE WARNING IS ADVISED
TO AVOID TRAVELING.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY/...
WE STILL EXPECT THE PRECIP TO BE TAPERING OFF FROM WEST TO EAST
STARTING AT DAYBREAK WEDNESDAY. THE ARCTIC HIGH WILL CONTINUE TO
SURGE INTO THE AREA WITH TEMPERATURES CONTINUING TO FALL THROUGH
THE 20S DURING THE MORNING HOURS. THE 18Z NAM AND GFS KEEP SOME
PRECIPITATION ALONG THE IMMEDIATE COAST...A BIT FARTHER BACK INTO
COASTAL SOUTHEAST GA INTO THE EARLY AFTERNOON HOURS. THE BRUNT OF
THE PRECIP ON WEDNESDAY WILL BE SNOW WITH A LITTLE SLEET ALSO
POSSIBLE. ASSUMING WE HAVE SOME ICE ON THE GROUND IN MOST AREAS ON
WEDNESDAY...THIS COMBINED WITH CONTINUED COLD ADVECTION AND CLOUDY
SKIES WILL KEEP TEMPERATURES FROM INCREASING MUCH. WE WILL
PROBABLY NOT BREAK FREEZING ACROSS NORTHERN AREAS WHILE FARTHER TO
THE SOUTH TEMPS MAY BRIEFLY REACH 34-35F DURING THE LATE AFTERNOON
BEFORE DROPPING BACK BELOW FREEZING. MUCH OF THE ICE THAT REMAINS
AFTER THE PRECIP ENDS WILL PROBABLY NOT MELT VERY MUCH ON
WEDNESDAY.
WEDNESDAY NIGHT...THE CENTER OF STRONG HIGH PRESSURE WILL SETTLE
ACROSS INLAND AREAS OVERNIGHT. THE RESULTING LIGHT WINDS...WHEN
COMBINED WITH CLEAR SKIES...WILL SUPPORT AN IDEAL RADIATIONAL
COOLING ENVIRONMENT. CONSIDERING THE ALREADY COLD AIR MASS IN PLACE
THAT SUPPRESSED DAYTIME HIGH TEMPERATURES...CONDITIONS OVERNIGHT
WILL EASILY FALL INTO THE TEENS AND LOWER 20S FOR MOST LOCATIONS
AWAY FROM THE IMMEDIATE COASTLINE. A BAROCLINIC ZONE PERSISTING
OFFSHORE WILL MAINTAIN RAIN CHANCES OVER THE NEARBY ATLANTIC WATERS.
WILL NEED TO CAREFULLY MONITOR NUMERICAL MODEL SOLUTIONS...AS A
WESTWARD SHIFT IN THE BAROCLINIC ZONE AND AN ASSOCIATED WAVE OF LOW
PRESSURE COULD ALLOW PRECIPITATION TO PUSH LOCALLY ONSHORE.
THURSDAY...THE SURFACE HIGH WILL WEAKEN SLIGHTLY AS IT MOVES
DIRECTLY OVER THE SOUTHEAST STATES...WHILE THE OFFSHORE WAVE OF
LOW PRESSURE PULLS FARTHER OUT TO SEA. ANY PRECIPITATION
LINGERING NEAR THE COAST DURING THE MORNING WILL ALSO SHIFT INTO
THE OFFSHORE WATERS...WITH PRECIPITATION POTENTIAL REMAINING
BELOW 15 PERCENT. THE TRANSITIONING SURFACE PATTERN WILL ALLOW
TEMPERATURES TO MODERATE...YET STILL BE SUPPRESSED WELL BELOW
SEASONAL NORMALS. HIGHS WILL RISE ONLY INTO THE 40 DEGREE
RANGE...WITH LOW TEMPERATURES STILL ABLE TO FALL INTO THE 20S UNDER
MOSTLY CLEAR SKIES AND LIGHT WINDS.
FRIDAY...THE WARMING TREND WILL CONTINUE INTO THE LATE WEEK
PERIOD...AS DRY SURFACE HIGH PRESSURE LINGERS AND FLAT UPPER
RIDGING OVER THE BAHAMAS ATTEMPTS TO PUSH NORTHWARD. HIGH
TEMPERATURES WILL REACH THE LOW TO MID 50S.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
THE FIRST HALF OF THE EXTENDED PERIOD WILL SEE A WARMING
TREND...AS SURFACE HIGH PRESSURE SLIDES EASTWARD INTO THE
ATLANTIC...HEIGHTS BUILD WITHIN A QUASI-ZONAL FLOW ALOFT AND WARM
ADVECTION ENSUES. HOWEVER...THIS MIGHT ONLY BE SHORT-LIVED AS THE
NEXT COLD FRONT LOOKS TO IMPACT THE AREA EARLY NEXT WEEK. MOISTURE
WILL INCREASE IN ADVANCE OF THE FRONT...AND HAVE INDICATED SLIGHT
CHANCE/CHANCE POPS FOR THE WEEKEND. TEMPERATURES WILL ACTUALLY BE
ABOVE NORMAL FOR A GOOD PART OF THE EXTENDED PERIOD.
&&
.AVIATION /22Z TUESDAY THROUGH SUNDAY/...
EXPECT LIGHT PRECIPITATION TO GRADUALLY INCREASE IN COVERAGE BY
LATE AFTERNOON/EARLY EVENING...WHILE REMAINING INITIALLY IN
LIQUID FORM UNTIL THE EVENING HOURS AS TEMPERATURES DROP BELOW
FREEZING. HAVE DELAYED THE INTRODUCTION OF FREEZING RAIN AND SLEET
AT KCHS UNTIL 02Z AND KSAV UNTIL 03Z. WILL THEN INDICATE A
CHANGEOVER OR MIX WITH SNOW AT KCHS DURING THE PRE-DAWN HOURS.
SLIGHTLY WARMER AIR IN THE MID LEVELS WILL POTENTIALLY KEEP
PRECIPITATION AS FREEZING RAIN/SLEET FARTHER SOUTH AT KSAV. THERE
IS CONSIDERABLE UNCERTAINTY REGARDING THE PERSISTENCE OF
PRECIPITATION BY MID MORNING WEDNESDAY...AND PREFER TO KEEP ANY
MENTION OUT OF THE FORECAST UNTIL CONFIDENCE INCREASES IN
COVERAGE/TIMING.
MODEL GUIDANCE IS IN FAIRLY GOOD AGREEMENT THAT ONGOING MVFR
CEILINGS WILL EVENTUALLY FALL INTO THE IFR RANGE AFTER 02Z TO 03Z
THIS EVENING. NORTHERLY WINDS WILL ACTUALLY INCREASE A BIT
OVERNIGHT...AND THUS VISIBILITIES WILL REMAIN IN THE MVFR RANGE
UNTIL AROUND DAYBREAK.
EXTENDED AVIATION OUTLOOK...LINGERING SNOW AND/OR FREEZING RAIN
WEDNESDAY MORNING WILL COME TO AN END DURING THE AFTERNOON. IFR OR
LOWER CONDITIONS WILL PREVAIL FOR THE BULK OF WEDNESDAY...BEFORE VFR
CONDITIONS RETURN WEDNESDAY NIGHT THROUGH SATURDAY.
&&
.MARINE...
TONIGHT AND WEDNESDAY...A WAVE OF LOW PRESSURE WILL SLOWLY DEEPEN
AS IT LIFTS RAPIDLY NORTHEAST TONIGHT AND OFF THE NEW ENGLAND
COASTLINE ON WEDNESDAY. HIGH PRESSURE WILL STEADILY BUILD EAST IN
THE WAKE OF THE DEPARTING LOW SYSTEM. CONTINUED COLD ADVECTION
AND A FAIRLY TIGHT PRESSURE GRADIENT WILL ALLOW NORTH WINDS TO
REMAIN ELEVATED...AND THUS SMALL CRAFT ADVISORY CONDITIONS WILL
CONTINUE FOR ALL MARINE ZONES OUTSIDE OF THE CHARLESTON
HARBOR. SEAS WILL ALSO BUILD INTO THE 5 TO 7 FT RANGE NEARSHORE
AND 8 TO 10 FT OFFSHORE. A CONSTANT INFLUX OF COLDER AIR INTO THE
REGION WILL CAUSE RAIN TO MIX WITH AND/OR EVEN CHANGE OVER TO SOME
FROZEN/FREEZING PRECIPITATION IN THE CHARLESTON HARBOR AND ACROSS
PORTIONS OF THE NEARSHORE WATERS.
WEDNESDAY NIGHT AND THURSDAY...HIGH PRESSURE WILL PROGRESS EAST
AND SHOULD KEEP ANOTHER WAVE OF LOW PRESSURE FAR TO THE
EAST/SOUTHEAST OF THE LOCAL WATERS. THERE WILL STILL BE A
SUFFICIENT PRESSURE GRADIENT TO SUPPORT CONTINUED ADVISORY
CONDITIONS THROUGH AT LEAST THURSDAY MORNING FOR NEARSHORE WATERS
AND INTO THURSDAY NIGHT OFFSHORE ZONES.
FRIDAY THROUGH SUNDAY...EXPECT IMPROVING MARINE CONDITIONS AS THE
SURFACE HIGH LINGERS OVER THE LOCAL WATERS FRIDAY...THEN SHIFTS
FURTHER INTO THE ATLANTIC SATURDAY. ANOTHER COLD FRONT LOOKS TO
APPROACH AT SOME POINT EARLY NEXT WEEK...AND WINDS/SEAS WILL AGAIN
CLIMB TOWARD POSSIBLE ADVISORY LEVELS.
&&
.TIDES/COASTAL FLOODING...
DUE TO THE UPCOMING PERIGEAN SPRING TIDES THERE IS A RISK OF SHALLOW
COASTAL FLOODING DURING THE MIDDLE AND LATTER PARTS OF THE WEEK.
&&
.CLIMATE...
RECORD LOW MAX TEMPS FOR JANUARY 29TH...
KCHS...41 SET IN 2000.
KCHL...36 SET IN 1897.
KSAV...33 SET IN 1897.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...WINTER STORM WARNING UNTIL 5 PM EST WEDNESDAY FOR GAZ087-088-
099>101-114>119-137>141.
SC...WINTER STORM WARNING UNTIL 5 PM EST WEDNESDAY FOR SCZ040-
042>045-047>052.
MARINE...SMALL CRAFT ADVISORY UNTIL 5 PM EST WEDNESDAY FOR AMZ350-352-
354.
SMALL CRAFT ADVISORY UNTIL 5 PM EST THURSDAY FOR AMZ374.
&&
$$
SYNOPSIS...
NEAR TERM...JRL
SHORT TERM...JRL/WMS
LONG TERM...33/WMS
AVIATION...WMS
MARINE...JRL/WMS
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
437 PM EST TUE JAN 28 2014
.SYNOPSIS...
ARCTIC HIGH PRESSURE WILL BUILD INTO THE AREA FROM THE NORTH
TONIGHT WHILE WAVES OF LOW PRESSURE TRAVEL NORTHWARD ALONG A
STALL FRONTAL BOUNDARY OFF THE COAST. THIS LOW WILL PUSH MOISTURE
INLAND...AND THIS MOISTURE COMBINED WITH THE COLD AIR WILL BRING
WINTRY PRECIPITATION. DRYING WILL OCCUR WEDNESDAY AS THE LOW
SHIFTS FARTHER NORTHEAST. COLD HIGH PRESSURE WILL DOMINATE
WEDNESDAY NIGHT AND THURSDAY.
&&
.NEAR TERM /THROUGH WEDNESDAY NIGHT/...
THE WINTER STORM WARNING REMAINS IN EFFECT FOR THE ENTIRE FORECAST
AREA INTO WEDNESDAY MORNING.
PRECIPITATION COVERAGE IS INCREASING MAINLY ASSOCIATED WITH WEAK
ISENTROPIC LIFT AND LARGE-SCALE LIFT ASSOCIATED WITH THE RIGHT-
ENTRANCE REGION OF THE UPPER JET. SURFACE WET-BULB TEMPERATURES
ARE BELOW FREEZING. EVAPORATIVE COOLING WILL HELP CAUSE FALLING
TEMPERATURES. THE HIGH-RESOLUTION MODELS SHOW COOLING WILL OCCUR
AND WE STILL EXPECT MIXED PRECIPITATION WILL BECOME ALL SNOW.
KEPT CATEGORICAL POPS. POPS WILL BEGIN TO DIMINISH FROM WEST TO
EAST LATE TONIGHT AS THE SURFACE LOW OFF THE COAST BEGINS TO LIFT
AWAY FROM THE REGION AND DRIER AIR FILTERS IN FROM THE WEST.
EXPECT MAINLY FREEZING RAIN AND SLEET IN THE EASTERN MIDLANDS AND
CSRA EVENTUALLY MIXING WITH SNOW AND CHANGING OVER TO ALL SNOW
LATE TONIGHT. ACROSS THE CENTRAL MIDLANDS AND CSRA THE DOMINANT
PRECIP TYPE APPEARS TO BE SLEET EARLY ON AND THEN MIXING WITH AND
CHANGING TO SNOW...WHILE THE WESTERN AND NORTHERN MIDLANDS SHOULD
SEE MAINLY SNOW BUT SOME SLEET COULD BE MIXED IN AT TIMES THROUGH
THE EARLY EVENING. AS THE STORM SYSTEM PROGRESSES THE ATMOSPHERIC
COLUMN WILL COOL FROM WEST TO EAST AND PRECIP TYPE WILL GRADUALLY
TRANSITION TO ALL SNOW OVERNIGHT AS PRECIPITATION COMES TO AN END.
DURING PERIODS OF HEAVIER INTENSITY...SNOW WILL LIKELY BECOME THE
DOMINANT PRECIP TYPE IN AREAS WHERE THAT WARM NOSE IS
SHALLOW...AND THEN DURING WEAKER INTENSITY THE SNOW MAY MIX WITH
OR CHANGE TO SLEET.
MODEL FORECAST PRECIPITATION AMOUNTS ARE IN GOOD AGREEMENT SHOWING
AROUND A QUARTER TO A THIRD OF AN INCH OF LIQUID IN THE WESTERN
PART OF THE AREA...AROUND A HALF INCH OR SO IN THE CENTRAL...AND
AROUND 0.70-0.90 INCHES IN THE EASTERN MIDLANDS. WHEN CONSIDERING
THE VARIOUS PRECIPITATION TYPES EXPECTED ACROSS THE AREA AND MANY
LOCATIONS RECEIVING A MIXTURE OF PRECIP TYPES...WE EXPECT LOWER
SNOW LIQUID RATIOS AND EVENTUAL SNOW/SLEET ACCUMULATIONS THAN
OTHERWISE MIGHT BE EXPECTED IN A SINGLE PRECIP TYPE EVENT.
EXPECT GENERALLY SNOW ACCUMULATIONS OF 1 TO 3 INCHES (SOME SLEET
MIXED IN AS WELL) IN THE PIEDMONT...INCLUDING THE AREA EXTENDING
FROM MCCORMICK TO SALUDA TO NEWBERRY TO FAIRFIELD...TO LANCASTER.
SNOW AND SLEET ACCUMULATIONS OF 2 TO 4 INCHES IN THE CENTRAL
SAVANNAH RIVER AREA AND MIDLANDS...INCLUDING THE AREA FROM AUGUSTA
TO AIKEN TO COLUMBIA. SLIGHTLY HIGHER ACCUMULATIONS OF 3 TO 5
INCHES ARE EXPECTED FROM CAMDEN TO SUMTER TO BISHOPVILLE TO MCBEE TO
CHERAW. HAVE ALSO ADDED DUE TO CURRENT CONDITIONS A GREATER
MENTION OF A PERIOD OF FREEZING RAIN AND SLEET ALONG THE I-20
CORRIDOR. SOME AREAS COULD SEE UP TO ONE TENTH OF AN INCH OF ICE
ACCUMULATION.
ACROSS THE SOUTHEASTERN MIDLANDS AND LOWER SAVANNAH RIVER AREA A
MIXTURE OF FREEZING RAIN...SLEET AND SNOW IS EXPECTED. THIS INCLUDES
THE AREA EXTENDING FROM WAYNESBORO TO BARNWELL TO BAMBERG AND
ORANGEBURG TO MANNING. HERE...THE MOST LIKELY SNOW ACCUMULATIONS
WILL BE 2 TO 4 INCHES PLUS DAMAGING ICE ACCUMULATIONS OF AROUND
1/4 INCH ARE EXPECTED.
THERE IS SOME UNCERTAINTY IN THE ACCUMULATION FORECAST DUE TO PRECIP
TYPE ISSUES AND SMALL CHANGES IN THE VERTICAL PROFILE CAN HAVE
PROFOUND INFLUENCE ON PRECIP TYPE AND ACCUMULATION. CONFIDENCE
REMAINS HIGH THAT WE WILL REACH THE WINTER STORM WARNING CRITERIA
WHICH IS AT LEAST 2 INCHES OF SNOW...OR AT LEAST 1/4 OF AN INCH OF
ICE ACCUMULATION.
WINTRY SYSTEM WILL BE PUSHING EAST OF THE FORECAST AREA EARLY
WEDNESDAY MORNING...WITH SOME LINGERING LIGHT SNOW STILL POSSIBLE
ACROSS THE EXTREME EAST THROUGH LATE MORNING. SIGNIFICANT DRYING
WILL OCCUR WEDNESDAY AFTERNOON.
BIGGEST ISSUES FOR WEDNESDAY WILL REVOLVE AROUND THE LEFT-OVER
SURFACE SNOW/ICE...AND AFTERNOON HIGHS REMAINING AROUND FREEZING FOR
ALL BUT THE EXTREME SOUTHWESTERN COUNTIES. NORTHERLY WINDS...DRIER
AIR...AND SOME THINNING/CLEARING OF THE CLOUD COVER IN THE AFTERNOON
SHOULD ALL COMBINE TO HELP TO ERODE SOME OF THE REMNANT SNOW/ICE.
SOME SNOW/ICE WILL STILL REMAIN ON SURFACES WEDNESDAY NIGHT...WITH
SOME BLACK ICE POSSIBLE ON ROADWAYS. WITH CLEAR SKIES...LIGHT
WINDS...AND THE REMNANT SNOW/ICE...EXPECT OVERNIGHT LOWS WEDNESDAY
NIGHT TO FALL INTO THE LOWER TO MIDDLE TEENS.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
HIGH PRESSURE BUILDS IN FROM THE WEST. DRY AIR REMAINS THURSDAY
THROUGH FRIDAY NIGHT. SHOULD BEGIN TO SEE A SLOW WARM UP FROM
THURSDAY INTO FRIDAY. HIGHS THURSDAY SHOULD BE MOSTLY IN THE LOWER
TO MIDDLE 40S...WITH READINGS BY FRIDAY INTO THE UPPER 40S NORTH
TO THE MIDDLE 50S SOUTH.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
GFS SHOWING INDICATING BRINGING A COLD FRONT DOWN INTO OUR REGION
DURING THE LATE SATURDAY NIGHT/SUNDAY TIME FRAME...STALLING IT TO
OUR SOUTH. CHANCE POPS THROUGH MUCH OF THE PERIOD. TEMPERATURES
GENERALLY CLOSE TO OR A LITTLE ABOVE NORMAL.
&&
.AVIATION /22Z TUESDAY THROUGH SUNDAY/...
RADAR AND MODEL TRENDS SUPPORT PRECIPITATION BECOMING WIDESPREAD
THIS EVENING. CEILINGS WILL BE LOWERING INTO THE IFR CATEGORY.
USED THE GFS LAMP AND RAP TIME-HEIGHT DISPLAYS FOR THE TIMING.
OBSERVATION TRENDS AND THE HIGH-RESOLUTION MODELS INDICATE COOLING
WILL OCCUR AND MIXED PRECIPITATIONS SHOULD BECOME ALL SNOW. USED
THE RAP FOR THE TIMING. IMPROVEMENT SHOULD BEGIN BEGINNING AROUND
10Z AS THE FRONT SHIFTS FARTHER EASTWARD AND DRIER AIR FILTERS
INTO THE AREA. THE MAV AND MET MOS WERE IN GOOD AGREEMENT WITH THE
TIMING OF A RETURN TO MVFR AND VFR CONDITIONS.
EXTENDED AVIATION OUTLOOK...A FRONTAL SYSTEM MAY BRING WIDESPREAD
MVFR OR IFR CONDITIONS SATURDAY NIGHT AND SUNDAY.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...WINTER STORM WARNING UNTIL 9 AM EST WEDNESDAY FOR SCZ015-016-
018-020>022-025>031-035>038-041.
GA...WINTER STORM WARNING UNTIL 9 AM EST WEDNESDAY FOR GAZ040-
063>065-077.
&&
$$
77
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
401 PM EST TUE JAN 28 2014
.SYNOPSIS...
ARCTIC HIGH PRESSURE WILL BUILD INTO THE AREA FROM THE NORTH
TONIGHT WHILE WAVES OF LOW PRESSURE TRAVEL NORTHWARD ALONG A
STALL FRONTAL BOUNDARY OFF THE COAST. THIS LOW WILL PUSH MOISTURE
INLAND...AND THIS MOISTURE COMBINED WITH THE COLD AIR WILL BRING
WINTRY PRECIPITATION. DRYING WILL OCCUR WEDNESDAY AS THE LOW
SHIFTS FARTHER NORTHEAST. COLD HIGH PRESSURE WILL DOMINATE
WEDNESDAY NIGHT AND THURSDAY.
&&
.NEAR TERM /THROUGH WEDNESDAY NIGHT/...
THE WINTER STORM WARNING REMAINS IN EFFECT FOR THE ENTIRE FORECAST
AREA INTO WEDNESDAY MORNING.
PRECIPITATION COVERAGE IS INCREASING MAINLY ASSOCIATED WITH WEAK
ISENTROPIC LIFT AND LARGE-SCALE LIFT ASSOCIATED WITH THE RIGHT-
ENTRANCE REGION OF THE UPPER JET. SURFACE WET-BULB TEMPERATURES
ARE BELOW FREEZING. EVAPORATIVE COOLING WILL HELP CAUSE FALLING
TEMPERATURES. THE HIGH-RESOLUTION MODELS SHOW COOLING WILL OCCUR
AND WE STILL EXPECT MIXED PRECIPITATION WILL BECOME ALL SNOW.
KEPT CATEGORICAL POPS. POPS WILL BEGIN TO DIMINISH FROM WEST TO
EAST LATE TONIGHT AS THE SURFACE LOW OFF THE COAST BEGINS TO LIFT
AWAY FROM THE REGION AND DRIER AIR FILTERS IN FROM THE WEST.
EXPECT MAINLY FREEZING RAIN AND SLEET IN THE EASTERN MIDLANDS AND
CSRA EVENTUALLY MIXING WITH SNOW AND CHANGING OVER TO ALL SNOW
LATE TONIGHT. ACROSS THE CENTRAL MIDLANDS AND CSRA THE DOMINANT
PRECIP TYPE APPEARS TO BE SLEET EARLY ON AND THEN MIXING WITH AND
CHANGING TO SNOW...WHILE THE WESTERN AND NORTHERN MIDLANDS SHOULD
SEE MAINLY SNOW BUT SOME SLEET COULD BE MIXED IN AT TIMES THROUGH
THE EARLY EVENING. AS THE STORM SYSTEM PROGRESSES THE ATMOSPHERIC
COLUMN WILL COOL FROM WEST TO EAST AND PRECIP TYPE WILL GRADUALLY
TRANSITION TO ALL SNOW OVERNIGHT AS PRECIPITATION COMES TO AN END.
DURING PERIODS OF HEAVIER INTENSITY...SNOW WILL LIKELY BECOME THE
DOMINANT PRECIP TYPE IN AREAS WHERE THAT WARM NOSE IS
SHALLOW...AND THEN DURING WEAKER INTENSITY THE SNOW MAY MIX WITH
OR CHANGE TO SLEET.
MODEL FORECAST PRECIPITATION AMOUNTS ARE IN GOOD AGREEMENT SHOWING
AROUND A QUARTER TO A THIRD OF AN INCH OF LIQUID IN THE WESTERN
PART OF THE AREA...AROUND A HALF INCH OR SO IN THE CENTRAL...AND
AROUND 0.70-0.90 INCHES IN THE EASTERN MIDLANDS. WHEN CONSIDERING
THE VARIOUS PRECIPITATION TYPES EXPECTED ACROSS THE AREA AND MANY
LOCATIONS RECEIVING A MIXTURE OF PRECIP TYPES...WE EXPECT LOWER
SNOW LIQUID RATIOS AND EVENTUAL SNOW/SLEET ACCUMULATIONS THAN
OTHERWISE MIGHT BE EXPECTED IN A SINGLE PRECIP TYPE EVENT.
EXPECT GENERALLY SNOW ACCUMULATIONS OF 1 TO 3 INCHES (SOME SLEET
MIXED IN AS WELL) IN THE PIEDMONT...INCLUDING THE AREA EXTENDING
FROM MCCORMICK TO SALUDA TO NEWBERRY TO FAIRFIELD...TO LANCASTER.
SNOW AND SLEET ACCUMULATIONS OF 2 TO 4 INCHES IN THE CENTRAL
SAVANNAH RIVER AREA AND MIDLANDS...INCLUDING THE AREA FROM AUGUSTA
TO AIKEN TO COLUMBIA. SLIGHTLY HIGHER ACCUMULATIONS OF 3 TO 5
INCHES ARE EXPECTED FROM CAMDEN TO SUMTER TO BISHOPVILLE TO CHERAW.
ACROSS THE SOUTHEASTERN MIDLANDS AND LOWER SAVANNAH RIVER AREA A
MIXTURE OF FREEZING RAIN...SLEET AND SNOW IS EXPECTED. THIS INCLUDES
THE AREA EXTENDING FROM WAYNESBORO TO BARNWELL TO BAMBERG AND
ORANGEBURG TO MANNING. HERE...THE MOST LIKELY SNOW ACCUMULATIONS
WILL BE 2 TO 4 INCHES PLUS DAMAGING ICE ACCUMULATIONS OF 1/4 TO 1/2
OF AN INCH.
THERE IS SOME UNCERTAINTY IN THE ACCUMULATION FORECAST DUE TO PRECIP
TYPE ISSUES AND SMALL CHANGES IN THE VERTICAL PROFILE CAN HAVE
PROFOUND INFLUENCE ON PRECIP TYPE AND ACCUMULATION. CONFIDENCE
REMAINS HIGH THAT WE WILL REACH THE WINTER STORM WARNING CRITERIA
WHICH IS AT LEAST 2 INCHES OF SNOW...OR AT LEAST 1/4 OF AN INCH OF
ICE ACCUMULATION.
WINTRY SYSTEM WILL BE PUSHING EAST OF THE FORECAST AREA EARLY
WEDNESDAY MORNING...WITH SOME LINGERING LIGHT SNOW STILL POSSIBLE
ACROSS THE EXTREME EAST THROUGH LATE MORNING. SIGNIFICANT DRYING
WILL OCCUR WEDNESDAY AFTERNOON.
BIGGEST ISSUES FOR WEDNESDAY WILL REVOLVE AROUND THE LEFT-OVER
SURFACE SNOW/ICE...AND AFTERNOON HIGHS REMAINING AROUND FREEZING FOR
ALL BUT THE EXTREME SOUTHWESTERN COUNTIES. NORTHERLY WINDS...DRIER
AIR...AND SOME THINNING/CLEARING OF THE CLOUD COVER IN THE AFTERNOON
SHOULD ALL COMBINE TO HELP TO ERODE SOME OF THE REMNANT SNOW/ICE.
SOME SNOW/ICE WILL STILL REMAIN ON SURFACES WEDNESDAY NIGHT...WITH
SOME BLACK ICE POSSIBLE ON ROADWAYS. WITH CLEAR SKIES...LIGHT
WINDS...AND THE REMNANT SNOW/ICE...EXPECT OVERNIGHT LOWS WEDNESDAY
NIGHT TO FALL INTO THE LOWER TO MIDDLE TEENS.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
HIGH PRESSURE BUILDS IN FROM THE WEST. DRY AIR REMAINS THURSDAY
THROUGH FRIDAY NIGHT. SHOULD BEGIN TO SEE A SLOW WARM UP FROM
THURSDAY INTO FRIDAY. HIGHS THURSDAY SHOULD BE MOSTLY IN THE LOWER
TO MIDDLE 40S...WITH READINGS BY FRIDAY INTO THE UPPER 40S NORTH
TO THE MIDDLE 50S SOUTH.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
GFS SHOWING INDICATING BRINGING A COLD FRONT DOWN INTO OUR REGION
DURING THE LATE SATURDAY NIGHT/SUNDAY TIME FRAME...STALLING IT TO
OUR SOUTH. CHANCE POPS THROUGH MUCH OF THE PERIOD. TEMPERATURES
GENERALLY CLOSE TO OR A LITTLE ABOVE NORMAL.
&&
.AVIATION /21Z TUESDAY THROUGH SUNDAY/...
RADAR AND MODEL TRENDS SUPPORT PRECIPITATION BECOMING WIDESPREAD
THIS EVENING. CEILINGS WILL BE LOWERING INTO THE IFR CATEGORY.
USED THE GFS LAMP AND RAP TIME-HEIGHT DISPLAYS FOR THE TIMING.
OBSERVATION TRENDS AND THE HIGH-RESOLUTION MODELS INDICATE COOLING
WILL OCCUR AND MIXED PRECIPITATIONS SHOULD BECOME ALL SNOW. USED
THE RAP FOR THE TIMING. IMPROVEMENT SHOULD BEGIN BEGINNING AROUND
10Z AS THE FRONT SHIFTS FARTHER EASTWARD AND DRIER AIR FILTERS
INTO THE AREA. THE MAV AND MET MOS WERE IN GOOD AGREEMENT WITH THE
TIMING OF A RETURN TO MVFR AND VFR CONDITIONS.
EXTENDED AVIATION OUTLOOK...A FRONTAL SYSTEM MAY BRING WIDESPREAD
MVFR OR IFR CONDITIONS SATURDAY NIGHT AND SUNDAY.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...WINTER STORM WARNING UNTIL 9 AM EST WEDNESDAY FOR SCZ015-016-
018-020>022-025>031-035>038-041.
GA...WINTER STORM WARNING UNTIL 9 AM EST WEDNESDAY FOR GAZ040-
063>065-077.
&&
$$
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
1240 PM EST TUE JAN 28 2014
.UPDATE...
/ISSUED AT 1118 AM EST TUE JAN 28 2014/
ADDED NW GA TO THE ADVISORY. GETTING REPORTS OF ACCUMULATING SNOW
ON THE GROUND AROUND AN INCH.
&&
.PREV DISCUSSION... /ISSUED 1030 AM EST TUE JAN 28 2014/
UPDATE...
UPDATE MAINLY FOR PTYPES AND TEMPS.
TEMPERATURES ARE WARMER THAN ANTICIPATED ACROSS THE EASTERN
PORTION OF THE FORECAST AREA THIS MORNING. THIS WILL AFFECT THE
PTYPE...SO HAVE MADE SOME CHANGES.
PREV DISCUSSION... /ISSUED 638 AM EST TUE JAN 28 2014/
PREV DISCUSSION... /ISSUED 411 AM EST TUE JAN 28 2014/
SHORT TERM /TODAY THROUGH WEDNESDAY/...
OBVIOUSLY PRIMARY CONCERN IS TIMING AND MAGNITUDE OF WINTER WX
EVENT. WATCHING REGIONAL RADAR AND SAT TRENDS...SO FAR APPEARS TO
MATCH 06Z HRRR AND 00Z HIRES WINDOW NMM/ARW RUNS BEST. LARGE AREA OF
PRECIP DEVELOPING IN NRN LA SPREADING QUICKLY INTO MS. THESE MODELS
HAVE CONTINUED TREND OF PUSHING TWO BANDS INTO THE STATE...ONE BAND
OF WIDESPREAD LIGHT PRECIP OVER NEARLY ALL OF NW GA AND ANOTHER MORE
INTENSE AND NARROW BAND SOUTH OF I-20 TOWARD AREAS JUST SOUTH OF ATL
AND FFC BY 16Z. THOUGH LIQUID EQUIV PRECIP AMOUNTS IN NW GA BAND ARE
LIGHT...UP TO 0.10 SNOW TO LIQUID RATIOS WILL APPROACH 15 TO 20 IN
THIS AREA WITH VERY COLD AIR IN LOWEST 150MB. NORTHERN BAND SHOULD
DISSIPATE BY 18Z WHILE SOUTHERN BAND EXPLODES IN COVERAGE OVER AREAS
SOUTH AND EAST OF I-85. THIS LARGE AREA WILL SLOWLY SHIFT SOUTH
THROUGH THE REST OF THE AFTERNOON AND TONIGHT...CLEARING FAR SE
COUNTIES BY 15Z WED.
PTYPE IN THE LARGE BAND NOT MUCH DIFFERENT THAN PREV FCSTS. MODEL
THERMODYNAMIC PROFILES IN PRETTY GOOD AGREEMENT WITH PREDOMINATELY
SNOW NORTH OF THE FALL LINE /LA GRANGE TO WASHINGTON/...SNOW/SLEET
MIX THEN RAIN CHANGING TO FREEZING RAIN IN SOUTHERN 1/4TH OF CWA.
TEMPS APPEAR ON TRACK BUT MUCH DRIER AIR THAN EXPECTED AT THIS TIME
OVER NW 1/2 OF CWA WHICH COULD SIGNIFICANTLY AFFECT PTYPE. HAVE
LEANED MORE TOWARD FROZEN AND FREEZING PTYPES /SNOW...SLEET...
FREEZING RAIN/ OVER AREAS NORTH OF CSG-MCN-AGS LINE.
SNOW/SLEET AMOUNTS WERE INCREASED A LITTLE OVER NW GA TO CATCH FIRST
BAND THIS MORNING...BUT STILL 0.5-1.0 INCH. IN MAIN BAND FOR THE
AFTERNOON AND TONIGHT...HAVE SNOW/SLEET AMOUNTS OF 1-3 INCLUDING ATL
METRO. GREATEST AMOUNT ALONG A BROAD LINE FROM LA GRANGE TO
THOMASTON TO LOUISVILLE. BUT SOUTH OF LUMPKIN TO MACON TO SWAINSBORO
LINE...ACCUM WILL BE 0.1-0.3 INCH MIX OF SLEET AND FREEZING RAIN
WITH UP TO AN INCH OF LIGHT SNOW ON TOP. ALL THESE ACCUMULATION...
OTHER THAN THE NW GA LIGHT BAND...WILL MEET WARNING CRITERIA SO HAVE
CONTINUED WARNING AND EXPANDED THIS TO ANOTHER TIER OF COUNTIES
INCLUDING ATL METRO AREA.
FINAL NOTE...WE REMAIN CONCERNED ABOUT IMPACT WITH ONSET OF PRECIP
AROUND RUSH HOUR AND SCHOOL RELEASE. THAT SAID...THESE IS ALSO
POTENTIAL THAT DRY AIR WILL DELAY ONSET A FEW HOURS MORE THAN FCST.
ALSO SOME POTENTIAL THAT MAIN BAND COULD SET UP SOUTH OF ATL METRO
OR ONLY PRODUCES SNOW FOR 2 OR 3 HOURS OVER LARGER POPULATION
AREAS...LIMITING ACCUMULATION. FOR THIS FCST...WE SIDED WITH HIGHER
RESOLUTION MODELS WITH MODERN RADAR-BASED ASSIMILATION SUCH AS THE
HRRR...HIRES WINDOW RUNS AND LOCAL WRF MODEL. LARGER SCALE MODELS
SUCH AS THE 00Z GFS/ECMWF AND 06Z NAM WERE NOT TOO DIFFERENT.
THANKS FOR COORD SURROUNDING OFFICES.
SNELSON
LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
DRY SURFACE HIGH PRESSURE MOVES ACROSS THE AREA WEDNESDAY NIGHT AND
TO THE EASTERN SEABOARD THURSDAY WITH DRY WEATHER EXPECTED.
A WEAK COLD FRONT APPROACHES THE REGION FRIDAY BUT GETS HUNG UP BY
SURFACE HIGH PRESSURE ALONG THE EASTERN SEABOARD. IT WILL MAINLY
AMOUNT TO INCREASING MOISTURE AND CLOUDS...MOST SO FOR N GA.
DEVELOPING SURFACE LOW PRESSURE MOVES QUICKLY TOWARD CANADA ON
SATURDAY AND MOVES A COLD FRONT TO THE TN VALLEY LATE WITH
INCREASING RAIN CHANCES...MOST SO FOR N AND W GA. THE FRONT MOVES
MOSTLY ACROSS THE FORECAST AREA ON SUNDAY AND WILL LIKELY GET HUNG
UP ACROSS S GA. THE EUROPEAN IS MUCH WETTER THAN THE GFS ON SUNDAY.
A WETTER EUROPEAN AND DRIER GFS CONTINUE FOR MONDAY WITH THE PRECIP
FORECAST A CRAP SHOOT. ELECTED TO KEEP POPS AT 20 PERCENT FOR NOW.
ANOTHER DEVELOPING SURFACE LOW PRESSURE SYSTEM WILL BRING INCREASING
MOISTURE AND RAIN CHANCES TO THE AREA ON TUESDAY.
TEMPERATURES WILL BE BELOW NORMAL TO START WITH HIGHS ON FRIDAY
GETTING CLOSE TO NORMAL AND THEN TEMPERATURES MANY ABOVE NORMAL
AFTER FRIDAY.
BDL
&&
.AVIATION...
18Z UPDATE...
THE WINTRY MIX HAS SPREAD ACROSS THE WESTERN PART OF THE FORECAST
AREA AND WILL CONTINUE TO SPREAD EAST. ALL AREAS WILL BECOME IFR BY
MID AFTERNOON AND WILL LAST INTO THE EVENING HOURS. AS THE SYSTEM
PULLS OUT...DRIER AIR WILL SPREAD RAPIDLY INTO THE STATE WITH
CLEARING FROM THE NORTHWEST. WINDS WILL REMAIN NORTH NORTHWEST IN
THE ATL/CSG AREAS. IN AHN/MCN...NORTHEAST WINDS WILL BECOME NORTH
NORTHWEST BY 00Z. AFTER 12Z WED ALL TAF SITES SHOULD BE VFR.
//ATL CONFIDENCE...18Z UPDATE...
MEDIUM ON WINTER WEATHER TIMING AND INTENSITY.
HIGH ON REMAINING ELEMENTS.
17
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 34 20 38 18 / 90 90 10 0
ATLANTA 31 16 36 19 / 90 80 5 0
BLAIRSVILLE 27 12 31 11 / 80 40 5 0
CARTERSVILLE 27 15 33 12 / 80 40 5 0
COLUMBUS 35 21 37 19 / 100 100 10 0
GAINESVILLE 31 18 35 19 / 80 60 5 0
MACON 37 23 38 18 / 100 100 20 0
ROME 28 15 34 12 / 80 30 0 0
PEACHTREE CITY 32 18 36 12 / 100 100 5 0
VIDALIA 43 26 36 23 / 100 100 60 0
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING UNTIL 7 AM EST WEDNESDAY FOR THE FOLLOWING
ZONES: BALDWIN...BARROW...BIBB...BLECKLEY...BUTTS...CARROLL...
CHATTAHOOCHEE...CLARKE...CLAYTON...COBB...COWETA...CRAWFORD...
CRISP...DEKALB...DODGE...DOOLY...DOUGLAS...EMANUEL...FAYETTE...
GLASCOCK...GREENE...GWINNETT...HANCOCK...HARALSON...HARRIS...
HEARD...HENRY...HOUSTON...JACKSON...JASPER...JEFFERSON...
JOHNSON...JONES...LAMAR...LAURENS...MACON...MADISON...MARION...
MERIWETHER...MONROE...MONTGOMERY...MORGAN...MUSCOGEE...NEWTON...
NORTH FULTON...OCONEE...OGLETHORPE...PAULDING...PEACH...PIKE...
PULASKI...PUTNAM...ROCKDALE...SCHLEY...SOUTH FULTON...SPALDING...
STEWART...SUMTER...TALBOT...TALIAFERRO...TAYLOR...TELFAIR...
TOOMBS...TREUTLEN...TROUP...TWIGGS...UPSON...WALTON...WARREN...
WASHINGTON...WEBSTER...WHEELER...WILCOX...WILKES...WILKINSON.
WINTER WEATHER ADVISORY UNTIL 7 AM EST WEDNESDAY FOR THE
FOLLOWING ZONES: BANKS...BARTOW...CATOOSA...CHATTOOGA...
CHEROKEE...DADE...DAWSON...FANNIN...FLOYD...FORSYTH...GILMER...
GORDON...HALL...LUMPKIN...MURRAY...PICKENS...POLK...TOWNS...
UNION...WALKER...WHITE...WHITFIELD.
&&
$$
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
1118 AM EST TUE JAN 28 2014
.UPDATE...
ADDED NW GA TO THE ADVISORY. GETTING REPORTS OF ACCUMULATING SNOW
ON THE GROUND AROUND AN INCH.
&&
.PREV DISCUSSION... /ISSUED 1030 AM EST TUE JAN 28 2014/
UPDATE...
UPDATE MAINLY FOR PTYPES AND TEMPS.
TEMPERATURES ARE WARMER THAN ANTICIPATED ACROSS THE EASTERN
PORTION OF THE FORECAST AREA THIS MORNING. THIS WILL AFFECT THE
PTYPE...SO HAVE MADE SOME CHANGES.
PREV DISCUSSION... /ISSUED 638 AM EST TUE JAN 28 2014/
PREV DISCUSSION... /ISSUED 411 AM EST TUE JAN 28 2014/
SHORT TERM /TODAY THROUGH WEDNESDAY/...
OBVIOUSLY PRIMARY CONCERN IS TIMING AND MAGNITUDE OF WINTER WX
EVENT. WATCHING REGIONAL RADAR AND SAT TRENDS...SO FAR APPEARS TO
MATCH 06Z HRRR AND 00Z HIRES WINDOW NMM/ARW RUNS BEST. LARGE AREA OF
PRECIP DEVELOPING IN NRN LA SPREADING QUICKLY INTO MS. THESE MODELS
HAVE CONTINUED TREND OF PUSHING TWO BANDS INTO THE STATE...ONE BAND
OF WIDESPREAD LIGHT PRECIP OVER NEARLY ALL OF NW GA AND ANOTHER MORE
INTENSE AND NARROW BAND SOUTH OF I-20 TOWARD AREAS JUST SOUTH OF ATL
AND FFC BY 16Z. THOUGH LIQUID EQUIV PRECIP AMOUNTS IN NW GA BAND ARE
LIGHT...UP TO 0.10 SNOW TO LIQUID RATIOS WILL APPROACH 15 TO 20 IN
THIS AREA WITH VERY COLD AIR IN LOWEST 150MB. NORTHERN BAND SHOULD
DISSIPATE BY 18Z WHILE SOUTHERN BAND EXPLODES IN COVERAGE OVER AREAS
SOUTH AND EAST OF I-85. THIS LARGE AREA WILL SLOWLY SHIFT SOUTH
THROUGH THE REST OF THE AFTERNOON AND TONIGHT...CLEARING FAR SE
COUNTIES BY 15Z WED.
PTYPE IN THE LARGE BAND NOT MUCH DIFFERENT THAN PREV FCSTS. MODEL
THERMODYNAMIC PROFILES IN PRETTY GOOD AGREEMENT WITH PREDOMINATELY
SNOW NORTH OF THE FALL LINE /LA GRANGE TO WASHINGTON/...SNOW/SLEET
MIX THEN RAIN CHANGING TO FREEZING RAIN IN SOUTHERN 1/4TH OF CWA.
TEMPS APPEAR ON TRACK BUT MUCH DRIER AIR THAN EXPECTED AT THIS TIME
OVER NW 1/2 OF CWA WHICH COULD SIGNIFICANTLY AFFECT PTYPE. HAVE
LEANED MORE TOWARD FROZEN AND FREEZING PTYPES /SNOW...SLEET...
FREEZING RAIN/ OVER AREAS NORTH OF CSG-MCN-AGS LINE.
SNOW/SLEET AMOUNTS WERE INCREASED A LITTLE OVER NW GA TO CATCH FIRST
BAND THIS MORNING...BUT STILL 0.5-1.0 INCH. IN MAIN BAND FOR THE
AFTERNOON AND TONIGHT...HAVE SNOW/SLEET AMOUNTS OF 1-3 INCLUDING ATL
METRO. GREATEST AMOUNT ALONG A BROAD LINE FROM LA GRANGE TO
THOMASTON TO LOUISVILLE. BUT SOUTH OF LUMPKIN TO MACON TO SWAINSBORO
LINE...ACCUM WILL BE 0.1-0.3 INCH MIX OF SLEET AND FREEZING RAIN
WITH UP TO AN INCH OF LIGHT SNOW ON TOP. ALL THESE ACCUMULATION...
OTHER THAN THE NW GA LIGHT BAND...WILL MEET WARNING CRITERIA SO HAVE
CONTINUED WARNING AND EXPANDED THIS TO ANOTHER TIER OF COUNTIES
INCLUDING ATL METRO AREA.
FINAL NOTE...WE REMAIN CONCERNED ABOUT IMPACT WITH ONSET OF PRECIP
AROUND RUSH HOUR AND SCHOOL RELEASE. THAT SAID...THESE IS ALSO
POTENTIAL THAT DRY AIR WILL DELAY ONSET A FEW HOURS MORE THAN FCST.
ALSO SOME POTENTIAL THAT MAIN BAND COULD SET UP SOUTH OF ATL METRO
OR ONLY PRODUCES SNOW FOR 2 OR 3 HOURS OVER LARGER POPULATION
AREAS...LIMITING ACCUMULATION. FOR THIS FCST...WE SIDED WITH HIGHER
RESOLUTION MODELS WITH MODERN RADAR-BASED ASSIMILATION SUCH AS THE
HRRR...HIRES WINDOW RUNS AND LOCAL WRF MODEL. LARGER SCALE MODELS
SUCH AS THE 00Z GFS/ECMWF AND 06Z NAM WERE NOT TOO DIFFERENT.
THANKS FOR COORD SURROUNDING OFFICES.
SNELSON
LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
DRY SURFACE HIGH PRESSURE MOVES ACROSS THE AREA WEDNESDAY NIGHT AND
TO THE EASTERN SEABOARD THURSDAY WITH DRY WEATHER EXPECTED.
A WEAK COLD FRONT APPROACHES THE REGION FRIDAY BUT GETS HUNG UP BY
SURFACE HIGH PRESSURE ALONG THE EASTERN SEABOARD. IT WILL MAINLY
AMOUNT TO INCREASING MOISTURE AND CLOUDS...MOST SO FOR N GA.
DEVELOPING SURFACE LOW PRESSURE MOVES QUICKLY TOWARD CANADA ON
SATURDAY AND MOVES A COLD FRONT TO THE TN VALLEY LATE WITH
INCREASING RAIN CHANCES...MOST SO FOR N AND W GA. THE FRONT MOVES
MOSTLY ACROSS THE FORECAST AREA ON SUNDAY AND WILL LIKELY GET HUNG
UP ACROSS S GA. THE EUROPEAN IS MUCH WETTER THAN THE GFS ON SUNDAY.
A WETTER EUROPEAN AND DRIER GFS CONTINUE FOR MONDAY WITH THE PRECIP
FORECAST A CRAP SHOOT. ELECTED TO KEEP POPS AT 20 PERCENT FOR NOW.
ANOTHER DEVELOPING SURFACE LOW PRESSURE SYSTEM WILL BRING INCREASING
MOISTURE AND RAIN CHANCES TO THE AREA ON TUESDAY.
TEMPERATURES WILL BE BELOW NORMAL TO START WITH HIGHS ON FRIDAY
GETTING CLOSE TO NORMAL AND THEN TEMPERATURES MANY ABOVE NORMAL
AFTER FRIDAY.
BDL
AVIATION...
12Z UPDATE...
A TRANQUIL START TO WHAT LOOKS TO BE A VERY ACTIVE PERIOD WITH A
PLETHORA OF AVIATION HAZARDS FOR AREA TERMINALS. SHOULD INITIALLY
SEE AN INCREASE IN MID LEVEL MOISTURE THROUGH MORNING WITH MVFR
DECK DEVELOPING BY 15Z AT MOST SITES. ATTENTION THEN TURNS TO
WINTRY WX POTENTIAL WITH TRENDS SEEMING TO BE FURTHER NORTH WITH
-SN SHIELD TO ENCOMPASS ALL ATL TERMINALS. ALSO SEEING WARM NOSE
DEVELOPING ALOFT WHICH WOULD TEND TO ALLOW MORE SLEET TO MIX
IN...ESPECIALLY AT THE ONSET. START TIME A LITTLE EARLIER AT
AROUND 15Z TO 18Z WITH MAXIMUM INTENSITY BETWEEN 18Z AND 00Z. THIS
WILL APPLY FOR ATL...PDK...FTY...RYY...AND AHN. FOR SOUTHERN TAF
SITES...MORE PROBLEMATIC WITH A TRANSITION IN STORE FROM -FZRAPL
TO -SNPL AND FINALLY TO -SN AS SYSTEM EXITS AROUND 04Z. ALONG WITH
ALL THIS WILL COME A PERIOD OF IFR CONDITIONS WITH CIGS AND VSBY
DROPPING DURING TIMES OF MAXIMUM SNOW PERIODS.
//ATL CONFIDENCE...12Z UPDATE...
MEDIUM ON WINTER WEATHER TIMING AND INTENSITY.
HIGH ON REMAINING ELEMENTS.
DEESE
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 34 20 38 18 / 90 90 10 0
ATLANTA 31 16 36 19 / 90 80 5 0
BLAIRSVILLE 27 12 31 11 / 80 40 5 0
CARTERSVILLE 27 15 33 12 / 80 40 5 0
COLUMBUS 35 21 37 19 / 100 100 10 0
GAINESVILLE 31 18 35 19 / 80 60 5 0
MACON 37 23 38 18 / 100 100 20 0
ROME 28 15 34 12 / 80 30 0 0
PEACHTREE CITY 32 18 36 12 / 100 100 5 0
VIDALIA 43 26 36 23 / 100 100 60 0
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING UNTIL 7 AM EST WEDNESDAY FOR THE FOLLOWING
ZONES: BALDWIN...BARROW...BIBB...BLECKLEY...BUTTS...CARROLL...
CHATTAHOOCHEE...CLARKE...CLAYTON...COBB...COWETA...CRAWFORD...
CRISP...DEKALB...DODGE...DOOLY...DOUGLAS...EMANUEL...FAYETTE...
GLASCOCK...GREENE...GWINNETT...HANCOCK...HARALSON...HARRIS...
HEARD...HENRY...HOUSTON...JACKSON...JASPER...JEFFERSON...
JOHNSON...JONES...LAMAR...LAURENS...MACON...MADISON...MARION...
MERIWETHER...MONROE...MONTGOMERY...MORGAN...MUSCOGEE...NEWTON...
NORTH FULTON...OCONEE...OGLETHORPE...PAULDING...PEACH...PIKE...
PULASKI...PUTNAM...ROCKDALE...SCHLEY...SOUTH FULTON...SPALDING...
STEWART...SUMTER...TALBOT...TALIAFERRO...TAYLOR...TELFAIR...
TOOMBS...TREUTLEN...TROUP...TWIGGS...UPSON...WALTON...WARREN...
WASHINGTON...WEBSTER...WHEELER...WILCOX...WILKES...WILKINSON.
WINTER WEATHER ADVISORY UNTIL 7 AM EST WEDNESDAY FOR THE
FOLLOWING ZONES: BANKS...BARTOW...CATOOSA...CHATTOOGA...
CHEROKEE...DADE...DAWSON...FANNIN...FLOYD...FORSYTH...GILMER...
GORDON...HALL...LUMPKIN...MURRAY...PICKENS...POLK...TOWNS...
UNION...WALKER...WHITE...WHITFIELD.
&&
$$
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
1030 AM EST TUE JAN 28 2014
.UPDATE...
UPDATE MAINLY FOR PTYPES AND TEMPS.
TEMPERATURES ARE WARMER THAN ANTICIPATED ACROSS THE EASTERN
PORTION OF THE FORECAST AREA THIS MORNING. THIS WILL AFFECT THE
PTYPE...SO HAVE MADE SOME CHANGES.
&&
.PREV DISCUSSION... /ISSUED 638 AM EST TUE JAN 28 2014/
PREV DISCUSSION... /ISSUED 411 AM EST TUE JAN 28 2014/
SHORT TERM /TODAY THROUGH WEDNESDAY/...
OBVIOUSLY PRIMARY CONCERN IS TIMING AND MAGNITUDE OF WINTER WX
EVENT. WATCHING REGIONAL RADAR AND SAT TRENDS...SO FAR APPEARS TO
MATCH 06Z HRRR AND 00Z HIRES WINDOW NMM/ARW RUNS BEST. LARGE AREA OF
PRECIP DEVELOPING IN NRN LA SPREADING QUICKLY INTO MS. THESE MODELS
HAVE CONTINUED TREND OF PUSHING TWO BANDS INTO THE STATE...ONE BAND
OF WIDESPREAD LIGHT PRECIP OVER NEARLY ALL OF NW GA AND ANOTHER MORE
INTENSE AND NARROW BAND SOUTH OF I-20 TOWARD AREAS JUST SOUTH OF ATL
AND FFC BY 16Z. THOUGH LIQUID EQUIV PRECIP AMOUNTS IN NW GA BAND ARE
LIGHT...UP TO 0.10 SNOW TO LIQUID RATIOS WILL APPROACH 15 TO 20 IN
THIS AREA WITH VERY COLD AIR IN LOWEST 150MB. NORTHERN BAND SHOULD
DISSIPATE BY 18Z WHILE SOUTHERN BAND EXPLODES IN COVERAGE OVER AREAS
SOUTH AND EAST OF I-85. THIS LARGE AREA WILL SLOWLY SHIFT SOUTH
THROUGH THE REST OF THE AFTERNOON AND TONIGHT...CLEARING FAR SE
COUNTIES BY 15Z WED.
PTYPE IN THE LARGE BAND NOT MUCH DIFFERENT THAN PREV FCSTS. MODEL
THERMODYNAMIC PROFILES IN PRETTY GOOD AGREEMENT WITH PREDOMINATELY
SNOW NORTH OF THE FALL LINE /LA GRANGE TO WASHINGTON/...SNOW/SLEET
MIX THEN RAIN CHANGING TO FREEZING RAIN IN SOUTHERN 1/4TH OF CWA.
TEMPS APPEAR ON TRACK BUT MUCH DRIER AIR THAN EXPECTED AT THIS TIME
OVER NW 1/2 OF CWA WHICH COULD SIGNIFICANTLY AFFECT PTYPE. HAVE
LEANED MORE TOWARD FROZEN AND FREEZING PTYPES /SNOW...SLEET...
FREEZING RAIN/ OVER AREAS NORTH OF CSG-MCN-AGS LINE.
SNOW/SLEET AMOUNTS WERE INCREASED A LITTLE OVER NW GA TO CATCH FIRST
BAND THIS MORNING...BUT STILL 0.5-1.0 INCH. IN MAIN BAND FOR THE
AFTERNOON AND TONIGHT...HAVE SNOW/SLEET AMOUNTS OF 1-3 INCLUDING ATL
METRO. GREATEST AMOUNT ALONG A BROAD LINE FROM LA GRANGE TO
THOMASTON TO LOUISVILLE. BUT SOUTH OF LUMPKIN TO MACON TO SWAINSBORO
LINE...ACCUM WILL BE 0.1-0.3 INCH MIX OF SLEET AND FREEZING RAIN
WITH UP TO AN INCH OF LIGHT SNOW ON TOP. ALL THESE ACCUMULATION...
OTHER THAN THE NW GA LIGHT BAND...WILL MEET WARNING CRITERIA SO HAVE
CONTINUED WARNING AND EXPANDED THIS TO ANOTHER TIER OF COUNTIES
INCLUDING ATL METRO AREA.
FINAL NOTE...WE REMAIN CONCERNED ABOUT IMPACT WITH ONSET OF PRECIP
AROUND RUSH HOUR AND SCHOOL RELEASE. THAT SAID...THESE IS ALSO
POTENTIAL THAT DRY AIR WILL DELAY ONSET A FEW HOURS MORE THAN FCST.
ALSO SOME POTENTIAL THAT MAIN BAND COULD SET UP SOUTH OF ATL METRO
OR ONLY PRODUCES SNOW FOR 2 OR 3 HOURS OVER LARGER POPULATION
AREAS...LIMITING ACCUMULATION. FOR THIS FCST...WE SIDED WITH HIGHER
RESOLUTION MODELS WITH MODERN RADAR-BASED ASSIMILATION SUCH AS THE
HRRR...HIRES WINDOW RUNS AND LOCAL WRF MODEL. LARGER SCALE MODELS
SUCH AS THE 00Z GFS/ECMWF AND 06Z NAM WERE NOT TOO DIFFERENT.
THANKS FOR COORD SURROUNDING OFFICES.
SNELSON
LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
DRY SURFACE HIGH PRESSURE MOVES ACROSS THE AREA WEDNESDAY NIGHT AND
TO THE EASTERN SEABOARD THURSDAY WITH DRY WEATHER EXPECTED.
A WEAK COLD FRONT APPROACHES THE REGION FRIDAY BUT GETS HUNG UP BY
SURFACE HIGH PRESSURE ALONG THE EASTERN SEABOARD. IT WILL MAINLY
AMOUNT TO INCREASING MOISTURE AND CLOUDS...MOST SO FOR N GA.
DEVELOPING SURFACE LOW PRESSURE MOVES QUICKLY TOWARD CANADA ON
SATURDAY AND MOVES A COLD FRONT TO THE TN VALLEY LATE WITH
INCREASING RAIN CHANCES...MOST SO FOR N AND W GA. THE FRONT MOVES
MOSTLY ACROSS THE FORECAST AREA ON SUNDAY AND WILL LIKELY GET HUNG
UP ACROSS S GA. THE EUROPEAN IS MUCH WETTER THAN THE GFS ON SUNDAY.
A WETTER EUROPEAN AND DRIER GFS CONTINUE FOR MONDAY WITH THE PRECIP
FORECAST A CRAP SHOOT. ELECTED TO KEEP POPS AT 20 PERCENT FOR NOW.
ANOTHER DEVELOPING SURFACE LOW PRESSURE SYSTEM WILL BRING INCREASING
MOISTURE AND RAIN CHANCES TO THE AREA ON TUESDAY.
TEMPERATURES WILL BE BELOW NORMAL TO START WITH HIGHS ON FRIDAY
GETTING CLOSE TO NORMAL AND THEN TEMPERATURES MANY ABOVE NORMAL
AFTER FRIDAY.
BDL
AVIATION...
12Z UPDATE...
A TRANQUIL START TO WHAT LOOKS TO BE A VERY ACTIVE PERIOD WITH A
PLETHORA OF AVIATION HAZARDS FOR AREA TERMINALS. SHOULD INITIALLY
SEE AN INCREASE IN MID LEVEL MOISTURE THROUGH MORNING WITH MVFR
DECK DEVELOPING BY 15Z AT MOST SITES. ATTENTION THEN TURNS TO
WINTRY WX POTENTIAL WITH TRENDS SEEMING TO BE FURTHER NORTH WITH
-SN SHIELD TO ENCOMPASS ALL ATL TERMINALS. ALSO SEEING WARM NOSE
DEVELOPING ALOFT WHICH WOULD TEND TO ALLOW MORE SLEET TO MIX
IN...ESPECIALLY AT THE ONSET. START TIME A LITTLE EARLIER AT
AROUND 15Z TO 18Z WITH MAXIMUM INTENSITY BETWEEN 18Z AND 00Z. THIS
WILL APPLY FOR ATL...PDK...FTY...RYY...AND AHN. FOR SOUTHERN TAF
SITES...MORE PROBLEMATIC WITH A TRANSITION IN STORE FROM -FZRAPL
TO -SNPL AND FINALLY TO -SN AS SYSTEM EXITS AROUND 04Z. ALONG WITH
ALL THIS WILL COME A PERIOD OF IFR CONDITIONS WITH CIGS AND VSBY
DROPPING DURING TIMES OF MAXIMUM SNOW PERIODS.
//ATL CONFIDENCE...12Z UPDATE...
MEDIUM ON WINTER WEATHER TIMING AND INTENSITY.
HIGH ON REMAINING ELEMENTS.
DEESE
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 34 20 38 18 / 90 90 10 0
ATLANTA 31 16 36 19 / 90 80 5 0
BLAIRSVILLE 27 12 31 11 / 80 40 5 0
CARTERSVILLE 27 15 33 12 / 80 40 5 0
COLUMBUS 35 21 37 19 / 100 100 10 0
GAINESVILLE 31 18 35 19 / 80 60 5 0
MACON 37 23 38 18 / 100 100 20 0
ROME 28 15 34 12 / 80 30 0 0
PEACHTREE CITY 32 18 36 12 / 100 100 5 0
VIDALIA 43 26 36 23 / 100 100 60 0
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING UNTIL 7 AM EST WEDNESDAY FOR THE FOLLOWING
ZONES: DODGE...EMANUEL...JOHNSON...LAURENS...MONTGOMERY...
TELFAIR...TOOMBS...TREUTLEN...WHEELER...WILCOX.
WINTER STORM WARNING UNTIL 7 AM EST WEDNESDAY FOR THE FOLLOWING
ZONES: BALDWIN...BARROW...BIBB...BLECKLEY...BUTTS...CARROLL...
CHATTAHOOCHEE...CLARKE...CLAYTON...COBB...COWETA...CRAWFORD...
CRISP...DEKALB...DOOLY...DOUGLAS...FAYETTE...GLASCOCK...GREENE...
GWINNETT...HANCOCK...HARALSON...HARRIS...HEARD...HENRY...
HOUSTON...JACKSON...JASPER...JEFFERSON...JONES...LAMAR...MACON...
MADISON...MARION...MERIWETHER...MONROE...MORGAN...MUSCOGEE...
NEWTON...NORTH FULTON...OCONEE...OGLETHORPE...PAULDING...PEACH...
PIKE...PULASKI...PUTNAM...ROCKDALE...SCHLEY...SOUTH FULTON...
SPALDING...STEWART...SUMTER...TALBOT...TALIAFERRO...TAYLOR...
TROUP...TWIGGS...UPSON...WALTON...WARREN...WASHINGTON...
WEBSTER...WILKES...WILKINSON.
WINTER WEATHER ADVISORY UNTIL 7 AM EST WEDNESDAY FOR THE
FOLLOWING ZONES: BANKS...BARTOW...CHEROKEE...DAWSON...FANNIN...
FLOYD...FORSYTH...GILMER...GORDON...HALL...LUMPKIN...MURRAY...
PICKENS...POLK...TOWNS...UNION...WHITE...WHITFIELD.
&&
$$
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
638 AM EST TUE JAN 28 2014
.PREV DISCUSSION... /ISSUED 411 AM EST TUE JAN 28 2014/
SHORT TERM /TODAY THROUGH WEDNESDAY/...
OBVIOUSLY PRIMARY CONCERN IS TIMING AND MAGNITUDE OF WINTER WX
EVENT. WATCHING REGIONAL RADAR AND SAT TRENDS...SO FAR APPEARS TO
MATCH 06Z HRRR AND 00Z HIRES WINDOW NMM/ARW RUNS BEST. LARGE AREA OF
PRECIP DEVELOPING IN NRN LA SPREADING QUICKLY INTO MS. THESE MODELS
HAVE CONTINUED TREND OF PUSHING TWO BANDS INTO THE STATE...ONE BAND
OF WIDESPREAD LIGHT PRECIP OVER NEARLY ALL OF NW GA AND ANOTHER MORE
INTENSE AND NARROW BAND SOUTH OF I-20 TOWARD AREAS JUST SOUTH OF ATL
AND FFC BY 16Z. THOUGH LIQUID EQUIV PRECIP AMOUNTS IN NW GA BAND ARE
LIGHT...UP TO 0.10 SNOW TO LIQUID RATIOS WILL APPROACH 15 TO 20 IN
THIS AREA WITH VERY COLD AIR IN LOWEST 150MB. NORTHERN BAND SHOULD
DISSIPATE BY 18Z WHILE SOUTHERN BAND EXPLODES IN COVERAGE OVER AREAS
SOUTH AND EAST OF I-85. THIS LARGE AREA WILL SLOWLY SHIFT SOUTH
THROUGH THE REST OF THE AFTERNOON AND TONIGHT...CLEARING FAR SE
COUNTIES BY 15Z WED.
PTYPE IN THE LARGE BAND NOT MUCH DIFFERENT THAN PREV FCSTS. MODEL
THERMODYNAMIC PROFILES IN PRETTY GOOD AGREEMENT WITH PREDOMINATELY
SNOW NORTH OF THE FALL LINE /LA GRANGE TO WASHINGTON/...SNOW/SLEET
MIX THEN RAIN CHANGING TO FREEZING RAIN IN SOUTHERN 1/4TH OF CWA.
TEMPS APPEAR ON TRACK BUT MUCH DRIER AIR THAN EXPECTED AT THIS TIME
OVER NW 1/2 OF CWA WHICH COULD SIGNIFICANTLY AFFECT PTYPE. HAVE
LEANED MORE TOWARD FROZEN AND FREEZING PTYPES /SNOW...SLEET...
FREEZING RAIN/ OVER AREAS NORTH OF CSG-MCN-AGS LINE.
SNOW/SLEET AMOUNTS WERE INCREASED A LITTLE OVER NW GA TO CATCH FIRST
BAND THIS MORNING...BUT STILL 0.5-1.0 INCH. IN MAIN BAND FOR THE
AFTERNOON AND TONIGHT...HAVE SNOW/SLEET AMOUNTS OF 1-3 INCLUDING ATL
METRO. GREATEST AMOUNT ALONG A BROAD LINE FROM LA GRANGE TO
THOMASTON TO LOUISVILLE. BUT SOUTH OF LUMPKIN TO MACON TO SWAINSBORO
LINE...ACCUM WILL BE 0.1-0.3 INCH MIX OF SLEET AND FREEZING RAIN
WITH UP TO AN INCH OF LIGHT SNOW ON TOP. ALL THESE ACCUMULATION...
OTHER THAN THE NW GA LIGHT BAND...WILL MEET WARNING CRITERIA SO HAVE
CONTINUED WARNING AND EXPANDED THIS TO ANOTHER TIER OF COUNTIES
INCLUDING ATL METRO AREA.
FINAL NOTE...WE REMAIN CONCERNED ABOUT IMPACT WITH ONSET OF PRECIP
AROUND RUSH HOUR AND SCHOOL RELEASE. THAT SAID...THESE IS ALSO
POTENTIAL THAT DRY AIR WILL DELAY ONSET A FEW HOURS MORE THAN FCST.
ALSO SOME POTENTIAL THAT MAIN BAND COULD SET UP SOUTH OF ATL METRO
OR ONLY PRODUCES SNOW FOR 2 OR 3 HOURS OVER LARGER POPULATION
AREAS...LIMITING ACCUMULATION. FOR THIS FCST...WE SIDED WITH HIGHER
RESOLUTION MODELS WITH MODERN RADAR-BASED ASSIMILATION SUCH AS THE
HRRR...HIRES WINDOW RUNS AND LOCAL WRF MODEL. LARGER SCALE MODELS
SUCH AS THE 00Z GFS/ECMWF AND 06Z NAM WERE NOT TOO DIFFERENT.
THANKS FOR COORD SURROUNDING OFFICES.
SNELSON
LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
DRY SURFACE HIGH PRESSURE MOVES ACROSS THE AREA WEDNESDAY NIGHT AND
TO THE EASTERN SEABOARD THURSDAY WITH DRY WEATHER EXPECTED.
A WEAK COLD FRONT APPROACHES THE REGION FRIDAY BUT GETS HUNG UP BY
SURFACE HIGH PRESSURE ALONG THE EASTERN SEABOARD. IT WILL MAINLY
AMOUNT TO INCREASING MOISTURE AND CLOUDS...MOST SO FOR N GA.
DEVELOPING SURFACE LOW PRESSURE MOVES QUICKLY TOWARD CANADA ON
SATURDAY AND MOVES A COLD FRONT TO THE TN VALLEY LATE WITH
INCREASING RAIN CHANCES...MOST SO FOR N AND W GA. THE FRONT MOVES
MOSTLY ACROSS THE FORECAST AREA ON SUNDAY AND WILL LIKELY GET HUNG
UP ACROSS S GA. THE EUROPEAN IS MUCH WETTER THAN THE GFS ON SUNDAY.
A WETTER EUROPEAN AND DRIER GFS CONTINUE FOR MONDAY WITH THE PRECIP
FORECAST A CRAP SHOOT. ELECTED TO KEEP POPS AT 20 PERCENT FOR NOW.
ANOTHER DEVELOPING SURFACE LOW PRESSURE SYSTEM WILL BRING INCREASING
MOISTURE AND RAIN CHANCES TO THE AREA ON TUESDAY.
TEMPERATURES WILL BE BELOW NORMAL TO START WITH HIGHS ON FRIDAY
GETTING CLOSE TO NORMAL AND THEN TEMPERATURES MANY ABOVE NORMAL
AFTER FRIDAY.
BDL
.AVIATION...
12Z UPDATE...
A TRANQUIL START TO WHAT LOOKS TO BE A VERY ACTIVE PERIOD WITH A
PLETHORA OF AVIATION HAZARDS FOR AREA TERMINALS. SHOULD INITIALLY
SEE AN INCREASE IN MID LEVEL MOISTURE THROUGH MORNING WITH MVFR
DECK DEVELOPING BY 15Z AT MOST SITES. ATTENTION THEN TURNS TO
WINTRY WX POTENTIAL WITH TRENDS SEEMING TO BE FURTHER NORTH WITH
-SN SHIELD TO ENCOMPASS ALL ATL TERMINALS. ALSO SEEING WARM NOSE
DEVELOPING ALOFT WHICH WOULD TEND TO ALLOW MORE SLEET TO MIX
IN...ESPECIALLY AT THE ONSET. START TIME A LITTLE EARLIER AT
AROUND 15Z TO 18Z WITH MAXIMUM INTENSITY BETWEEN 18Z AND 00Z. THIS
WILL APPLY FOR ATL...PDK...FTY...RYY...AND AHN. FOR SOUTHERN TAF
SITES...MORE PROBLEMATIC WITH A TRANSITION IN STORE FROM -FZRAPL
TO -SNPL AND FINALLY TO -SN AS SYSTEM EXITS AROUND 04Z. ALONG WITH
ALL THIS WILL COME A PERIOD OF IFR CONDITIONS WITH CIGS AND VSBY
DROPPING DURING TIMES OF MAXIMUM SNOW PERIODS.
//ATL CONFIDENCE...12Z UPDATE...
MEDIUM ON WINTER WEATHER TIMING AND INTENSITY.
HIGH ON REMAINING ELEMENTS.
DEESE
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 34 20 38 18 / 90 90 10 0
ATLANTA 31 16 36 19 / 90 90 5 0
BLAIRSVILLE 27 12 31 11 / 80 30 5 0
CARTERSVILLE 27 15 33 12 / 80 40 5 0
COLUMBUS 35 21 37 19 / 100 100 10 0
GAINESVILLE 31 18 35 19 / 80 60 5 0
MACON 37 23 38 18 / 100 100 20 0
ROME 28 15 34 12 / 80 20 0 0
PEACHTREE CITY 32 18 36 12 / 100 100 5 0
VIDALIA 41 26 36 23 / 100 100 60 0
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING FROM 11 AM THIS MORNING TO 7 AM EST
WEDNESDAY FOR THE FOLLOWING ZONES: DODGE...EMANUEL...JOHNSON...
LAURENS...MONTGOMERY...TELFAIR...TOOMBS...TREUTLEN...WHEELER...
WILCOX.
WINTER STORM WARNING FROM 10 AM THIS MORNING TO 7 AM EST
WEDNESDAY FOR THE FOLLOWING ZONES: BALDWIN...BIBB...BLECKLEY...
BUTTS...CHATTAHOOCHEE...CRAWFORD...CRISP...DOOLY...GLASCOCK...
GREENE...HANCOCK...HARRIS...HOUSTON...JASPER...JEFFERSON...
JONES...LAMAR...MACON...MARION...MERIWETHER...MONROE...MORGAN...
MUSCOGEE...PEACH...PIKE...PULASKI...PUTNAM...SCHLEY...SPALDING...
STEWART...SUMTER...TALBOT...TALIAFERRO...TAYLOR...TROUP...
TWIGGS...UPSON...WARREN...WASHINGTON...WEBSTER...WILKES...
WILKINSON.
WINTER WEATHER ADVISORY UNTIL 7 AM EST WEDNESDAY FOR THE
FOLLOWING ZONES: BANKS...BARTOW...CHEROKEE...DAWSON...FANNIN...
FLOYD...FORSYTH...GILMER...GORDON...HALL...LUMPKIN...MURRAY...
PICKENS...POLK...TOWNS...UNION...WHITE...WHITFIELD.
WINTER STORM WARNING UNTIL 7 AM EST WEDNESDAY FOR THE FOLLOWING
ZONES: BARROW...CARROLL...CLARKE...CLAYTON...COBB...COWETA...
DEKALB...DOUGLAS...FAYETTE...GWINNETT...HARALSON...HEARD...
HENRY...JACKSON...MADISON...NEWTON...NORTH FULTON...OCONEE...
OGLETHORPE...PAULDING...ROCKDALE...SOUTH FULTON...WALTON.
&&
$$
SHORT TERM...DEESE
LONG TERM....BDL
AVIATION...DEESE
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
411 AM EST TUE JAN 28 2014
.SHORT TERM /TODAY THROUGH WEDNESDAY/...
OBVIOUSLY PRIMARY CONCERN IS TIMING AND MAGNITUDE OF WINTER WX
EVENT. WATCHING REGIONAL RADAR AND SAT TRENDS...SO FAR APPEARS TO
MATCH 06Z HRRR AND 00Z HIRES WINDOW NMM/ARW RUNS BEST. LARGE AREA OF
PRECIP DEVELOPING IN NRN LA SPREADING QUICKLY INTO MS. THESE MODELS
HAVE CONTINUED TREND OF PUSHING TWO BANDS INTO THE STATE...ONE BAND
OF WIDESPREAD LIGHT PRECIP OVER NEARLY ALL OF NW GA AND ANOTHER MORE
INTENSE AND NARROW BAND SOUTH OF I-20 TOWARD AREAS JUST SOUTH OF ATL
AND FFC BY 16Z. THOUGH LIQUID EQUIV PRECIP AMOUNTS IN NW GA BAND ARE
LIGHT...UP TO 0.10 SNOW TO LIQUID RATIOS WILL APPROACH 15 TO 20 IN
THIS AREA WITH VERY COLD AIR IN LOWEST 150MB. NORTHERN BAND SHOULD
DISSIPATE BY 18Z WHILE SOUTHERN BAND EXPLODES IN COVERAGE OVER AREAS
SOUTH AND EAST OF I-85. THIS LARGE AREA WILL SLOWLY SHIFT SOUTH
THROUGH THE REST OF THE AFTERNOON AND TONIGHT...CLEARING FAR SE
COUNTIES BY 15Z WED.
PTYPE IN THE LARGE BAND NOT MUCH DIFFERENT THAN PREV FCSTS. MODEL
THERMODYNAMIC PROFILES IN PRETTY GOOD AGREEMENT WITH PREDOMINATELY
SNOW NORTH OF THE FALL LINE /LA GRANGE TO WASHINGTON/...SNOW/SLEET
MIX THEN RAIN CHANGING TO FREEZING RAIN IN SOUTHERN 1/4TH OF CWA.
TEMPS APPEAR ON TRACK BUT MUCH DRIER AIR THAN EXPECTED AT THIS TIME
OVER NW 1/2 OF CWA WHICH COULD SIGNIFICANTLY AFFECT PTYPE. HAVE
LEANED MORE TOWARD FROZEN AND FREEZING PTYPES /SNOW...SLEET...
FREEZING RAIN/ OVER AREAS NORTH OF CSG-MCN-AGS LINE.
SNOW/SLEET AMOUNTS WERE INCREASED A LITTLE OVER NW GA TO CATCH FIRST
BAND THIS MORNING...BUT STILL 0.5-1.0 INCH. IN MAIN BAND FOR THE
AFTERNOON AND TONIGHT...HAVE SNOW/SLEET AMOUNTS OF 1-3 INCLUDING ATL
METRO. GREATEST AMOUNT ALONG A BROAD LINE FROM LA GRANGE TO
THOMASTON TO LOUISVILLE. BUT SOUTH OF LUMPKIN TO MACON TO SWAINSBORO
LINE...ACCUM WILL BE 0.1-0.3 INCH MIX OF SLEET AND FREEZING RAIN
WITH UP TO AN INCH OF LIGHT SNOW ON TOP. ALL THESE ACCUMULATION...
OTHER THAN THE NW GA LIGHT BAND...WILL MEET WARNING CRITERIA SO HAVE
CONTINUED WARNING AND EXPANDED THIS TO ANOTHER TIER OF COUNTIES
INCLUDING ATL METRO AREA.
FINAL NOTE...WE REMAIN CONCERNED ABOUT IMPACT WITH ONSET OF PRECIP
AROUND RUSH HOUR AND SCHOOL RELEASE. THAT SAID...THESE IS ALSO
POTENTIAL THAT DRY AIR WILL DELAY ONSET A FEW HOURS MORE THAN FCST.
ALSO SOME POTENTIAL THAT MAIN BAND COULD SET UP SOUTH OF ATL METRO
OR ONLY PRODUCES SNOW FOR 2 OR 3 HOURS OVER LARGER POPULATION
AREAS...LIMITING ACCUMULATION. FOR THIS FCST...WE SIDED WITH HIGHER
RESOLUTION MODELS WITH MODERN RADAR-BASED ASSIMILATION SUCH AS THE
HRRR...HIRES WINDOW RUNS AND LOCAL WRF MODEL. LARGER SCALE MODELS
SUCH AS THE 00Z GFS/ECMWF AND 06Z NAM WERE NOT TOO DIFFERENT.
THANKS FOR COORD SURROUNDING OFFICES.
SNELSON
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
DRY SURFACE HIGH PRESSURE MOVES ACROSS THE AREA WEDNESDAY NIGHT AND
TO THE EASTERN SEABOARD THURSDAY WITH DRY WEATHER EXPECTED.
A WEAK COLD FRONT APPROACHES THE REGION FRIDAY BUT GETS HUNG UP BY
SURFACE HIGH PRESSURE ALONG THE EASTERN SEABOARD. IT WILL MAINLY
AMOUNT TO INCREASING MOISTURE AND CLOUDS...MOST SO FOR N GA.
DEVELOPING SURFACE LOW PRESSURE MOVES QUICKLY TOWARD CANADA ON
SATURDAY AND MOVES A COLD FRONT TO THE TN VALLEY LATE WITH
INCREASING RAIN CHANCES...MOST SO FOR N AND W GA. THE FRONT MOVES
MOSTLY ACROSS THE FORECAST AREA ON SUNDAY AND WILL LIKELY GET HUNG
UP ACROSS S GA. THE EUROPEAN IS MUCH WETTER THAN THE GFS ON SUNDAY.
A WETTER EUROPEAN AND DRIER GFS CONTINUE FOR MONDAY WITH THE PRECIP
FORECAST A CRAP SHOOT. ELECTED TO KEEP POPS AT 20 PERCENT FOR NOW.
ANOTHER DEVELOPING SURFACE LOW PRESSURE SYSTEM WILL BRING INCREASING
MOISTURE AND RAIN CHANCES TO THE AREA ON TUESDAY.
TEMPERATURES WILL BE BELOW NORMAL TO START WITH HIGHS ON FRIDAY
GETTING CLOSE TO NORMAL AND THEN TEMPERATURES MANY ABOVE NORMAL
AFTER FRIDAY.
BDL
&&
.AVIATION...
06Z UPDATE...
A TRANQUIL START TO WHAT LOOKS TO BE A VERY ACTIVE PERIOD WITH A
PLETHORA OF AVIATION HAZARDS FOR AREA TERMINALS. SHOULD INITIALLY
SEE AN INCREASE IN MID LEVEL MOISTURE THROUGH MORNING WITH MVFR
DECK DEVELOPING BY 13Z AT MOST SITES. ATTENTION THEN TURNS TO
WINTRY WX POTENTIAL WITH TRENDS SEEMING TO BE FURTHER NORTH WITH
-SN SHIELD TO ENCOMPASS ALL ATL TERMINALS. START TIME A LITTLE
EARLIER AT AROUND 15Z TO 18Z WITH MAXIMUM INTENSITY BETWEEN 18Z
AND 00Z. THIS WILL APPLY FOR ATL...PDK...FTY...RYY...AND AHN. FOR
SOUTHERN TAF SITES...MORE PROBLEMATIC WITH A TRANSITION IN STORE
FROM -FZRAPL TO -SNPL AND FINALLY TO -SN AS SYSTEM EXITS AROUND
04Z. ALONG WITH ALL THIS WILL COME A PERIOD OF IFR CONDITIONS WITH
CIGS AND VSBY DROPPING DURING TIMES OF MAXIMUM SNOW PERIODS.
//ATL CONFIDENCE...06Z UPDATE...
MEDIUM ON WINTER WEATHER TIMING AND INTENSITY.
HIGH ON REMAINING ELEMENTS.
DEESE
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 34 20 38 18 / 90 90 10 0
ATLANTA 31 16 36 19 / 90 90 5 0
BLAIRSVILLE 27 12 31 11 / 80 30 5 0
CARTERSVILLE 27 15 33 12 / 80 40 5 0
COLUMBUS 35 21 37 19 / 100 100 10 0
GAINESVILLE 31 18 35 19 / 80 60 5 0
MACON 37 23 38 18 / 100 100 20 0
ROME 28 15 34 12 / 80 20 0 0
PEACHTREE CITY 32 18 36 12 / 100 100 5 0
VIDALIA 41 26 36 23 / 100 100 60 0
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING FROM 11 AM THIS MORNING TO 7 AM EST
WEDNESDAY FOR THE FOLLOWING ZONES: DODGE...EMANUEL...JOHNSON...
LAURENS...MONTGOMERY...TELFAIR...TOOMBS...TREUTLEN...WHEELER...
WILCOX.
WINTER STORM WARNING FROM 10 AM THIS MORNING TO 7 AM EST
WEDNESDAY FOR THE FOLLOWING ZONES: BALDWIN...BIBB...BLECKLEY...
BUTTS...CHATTAHOOCHEE...CRAWFORD...CRISP...DOOLY...GLASCOCK...
GREENE...HANCOCK...HARRIS...HOUSTON...JASPER...JEFFERSON...
JONES...LAMAR...MACON...MARION...MERIWETHER...MONROE...MORGAN...
MUSCOGEE...PEACH...PIKE...PULASKI...PUTNAM...SCHLEY...SPALDING...
STEWART...SUMTER...TALBOT...TALIAFERRO...TAYLOR...TROUP...
TWIGGS...UPSON...WARREN...WASHINGTON...WEBSTER...WILKES...
WILKINSON.
WINTER WEATHER ADVISORY FROM 9 AM THIS MORNING TO 7 AM EST
WEDNESDAY FOR THE FOLLOWING ZONES: BANKS...BARTOW...CHEROKEE...
DAWSON...FANNIN...FLOYD...FORSYTH...GILMER...GORDON...HALL...
LUMPKIN...MURRAY...PICKENS...POLK...TOWNS...UNION...WHITE...
WHITFIELD.
WINTER STORM WARNING FROM 9 AM THIS MORNING TO 7 AM EST
WEDNESDAY FOR THE FOLLOWING ZONES: BARROW...CARROLL...CLARKE...
CLAYTON...COBB...COWETA...DEKALB...DOUGLAS...FAYETTE...
GWINNETT...HARALSON...HEARD...HENRY...JACKSON...MADISON...
NEWTON...NORTH FULTON...OCONEE...OGLETHORPE...PAULDING...
ROCKDALE...SOUTH FULTON...WALTON.
&&
$$
SHORT TERM...SNELSON
LONG TERM....BDL
AVIATION...DEESE
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
310 PM CST TUE JAN 28 2014
.DISCUSSION...
308 PM CST
THE FORECAST CHALLENGES ON OUR WINTER SEESAW TURN FROM COLD BACK TO
SNOW DURING THE LATTER PART OF THE WEEK AND INTO SATURDAY. THIS IS A
FITTING END TO ONE OF THE SNOWIEST MONTHS ON RECORD FOR CHICAGO.
TONIGHT AND WEDNESDAY MORNING...
BROAD BUT WEAKENING HIGH PRESSURE PREVAILS ACROSS MUCH OF THE
OZARKS...OHIO RIVER VALLEY...AND CORN BELT. THE PRESSURE GRADIENT IS
NOT OVERLY TIGHT ACROSS THE FORECAST AREA AND WILL GENERALLY REMAIN
THE SAME TONIGHT BUT LOOKS TO BE ENOUGH TO SUPPORT SOME WIND.
SURFACE TEMPERATURES HAVE CLIMBED NICELY SOUTH OF THE SNOW
PACK WITH 12 ABOVE UP TO PONTIAC. DEW POINTS ARE ABOUT 5 TO 10
DEGREES HIGHER THAN YESTERDAY AT THIS TIME. FOR THESE REASONS FEEL
THAT TEMPERATURES TONIGHT WILL NOT BE AS COOL AS INITIALLY FORECAST
AND HAVE RISEN VALUES. FORECAST WIND CHILLS ARE MORE ON THE ORDER OF
15 TO 25 BELOW...WITH SOME PATCHY 25 TO 28 BELOW ACROSS NORTH
CENTRAL IL. WILL NOT GET FANCY WITH CANCELLING SOME OF THE
ADVISORY...BUT GIVEN FORECAST VALUES AND CONSIDERING WE ARE COMING
OUT OF LOWER TEMPERATURES AND WIND CHILLS THE PAST 36 HOURS...LET
ALONE EARLIER THIS MONTH...IT LOOKS PRETTY MARGINAL IN PLACES.
WEDNESDAY THROUGH THURSDAY NIGHT...
A STRONG LOBE AROUND THE PRONOUNCED EASTERN NOAM UPPER TROUGH WILL
ROTATE THROUGH QUEBEC WED NIGHT INTO THU STEERING A SURFACE COLD
FRONT SOUTHEAST INTO THE AREA BY THU. IN ADVANCE OF THIS,..WED
SHOULD EXPERIENCE NICE MODERATION IN TEMPS THANKS TO SOUTHWEST FLOW
AND FULL SUNSHINE. WEDNESDAY NIGHT LIKELY WILL SEE STEADY
TEMPERATURES...POSSIBLY EVEN SLOWLY RISING WHICH IS COMMONLY THE
CASE WITH STRONG SOUTHERLY FLOW IN THE COOL SEASON. SO HAVE
CONTINUED TO INCREASE FORECAST MINS NEAR THE HIGHS ON WED. THE
FORCING FOR PRECIP WITH THE FRONT ITSELF LOOKS REALLY
WEEK...HOWEVER AS A WEST-TO-EAST JET STREAK AND ASSOCIATED SHORT
WAVE INTERACT WITH THE FRONT BY THU AFTERNOON...MODEL GUIDANCE IS IN
AGREEMENT WITH ENHANCING MAINLY LIGHT SNOW COVERAGE INTO THE EVE.
COLUMN MOISTURE LOOKS MORE SUPPORTIVE IN THE NORTH FOR LIKELY POPS
AND THATS WHERE HAVE THEM CONFINED...AND TAPER QUICKLY TO SMALL
CHANCES BY THE SOUTH CWA. RIGHT NOW HAVE LIGHT SNOW ACCUMULATING TO
AN INCH...MAYBE A LITTLE HIGHER...NORTH OF I-88.
FRIDAY INTO SATURDAY...
AFOREMENTIONED THURSDAY AFTERNOON/NIGHT COLD FRONT LOOKS TO DRAPE
OUT ACROSS THE AREA FRI UNDER QUASI-ZONAL FLOW ALOFT. WEAK HIGH
PRESSURE LOOKS TO PROVIDE A BREAK-IN-THE-ACTION FOR A PERIOD. THE EC
AND GFS CONTINUE TO DIFFER ON TIMING OF A PACIFIC WAVE TIGHTENING
THIS BAROCLINICITY AND BRINGING BETTER FORCING FOR PRECIP. OVERALL
BOTH MODELS HAVE A GOOD UPPER JET SETUP TO DEVELOP FOCUSED WARM AIR
ADVECTION/ISENTROPIC ASCENT ACROSS THE BOUNDARY...SO FEEL THAT
LIKELY POPS WERE NEEDED. CONTINUE TO FAVOR THE SLIGHTLY QUICKER
EC...BUT A LITTLE MORE IN THE MIDDLE GROUND WITH CONTINUING SOME
HIGHER POPS ON SATURDAY...NAMELY IN EASTERN AREAS. MOISTURE VALUES
WITH THIS SYSTEM ARE NOT SHABBY WITH 3-4 G/KG ON LIFTING SURFACES.
COULD EASILY FORESEE SEVERAL INCHES OF SNOW WITH A BLEND OF THESE
MODELS...ESPECIALLY IF THE GFS WERE TO VERIFY WITH BETTER SYNOPTIC
SYSTEM DEVELOPMENT IMPACTING THE AREA IN ITS LAST SEVERAL RUNS.
MTF
SATURDAY NIGHT THROUGH MID NEXT WEEK...
LARGEST STORY IN THE EXTENDED WILL BE FOCUSED ON THE POTENTIAL FOR
SIGNIFICANT STORM SYSTEM TO IMPACT A PORTION OF THE EASTERN CONUS.
ENSEMBLES HAVE CONTINUED TO INDICATE SOME CONSISTENCY WITH THE
PLACEMENT OF A 500MB TROUGH BECOMING SITUATED ACROSS THE SOUTHEAST
CONUS/ATLANTIC SEABOARD MON/TUE. BUT PRIOR TO THIS SYSTEM...SAT NGT
THROUGH MON LOOKS TO BE RATHER QUIET WITH A BROAD ANTI-CYCLONIC
FEATURE KEEPING DRY WEATHER FOR THE FORECAST AREA. SOME MOISTURE
DOES APPEAR TO CREEP BACK INTO THE REGION MON...HOWEVER AT THIS TIME
THIS IS A LOW CHANCE EVENT.
THEN THE FOCUS TURNS TOWARDS THE SYSTEM PROGGED FOR TUE/WED. 500MB
TROUGH AXIS IS POISED TO DIG INTO THE FOUR-CORNERS REGION...EJECTING
A LOBE OF VORTICITY INTO THE SOUTHERN PLAINS. WITH THE PLACEMENT OF
A DOWNSTREAM MID-LVL RIDGE PARKED OVER THE SOUTHEAST CONUS ALLOWING
SUBSTANTIAL RETURN FLOW MOISTURE TO BE POISED TO STREAM NORTH.
CURRENT FORECASTS FROM ENSEMBLES IS THAT THIS SYSTEM WILL QUICKLY
DEVELOP AND LIFT NORTHEAST. OPERATIONAL GUIDANCE HAS SHOWN
DIFFERENCES AND SOME CORRECTIONS WITH THE RECENT CYCLES...AND THIS
WILL LIKELY PERSIST THROUGH THE NEXT SEVERAL DAYS. ALTHOUGH WITH THE
LONG-WAVE PATTERN BEGINNING TO UNDERGO CHANGES...THIS PATTERN IS NOW
SUGGESTIVE OF CLASSIC WINTER STORM SYSTEMS THAT LIFT NORTHEAST
THROUGH THE OHIO VALLEY.
TEMPS CURRENTLY ARE POISED FOR HIGHS ARND 20 POSSIBLY LOW 20S. IF
THIS SYSTEM NEXT WEEK DOES INDEED STRENGTHEN AS EXPECTED...IT WILL
LIKELY DRIFT FURTHER NORTH WITH TIME AND PLACE THE SWEET SPOT
SOMEWHERE CLOSER TO OUR FORECAST AREA.
CONFIDENCE IN TEMPS FOR THE EXTENDED...HIGH.
CONFIDENCE IN SNOW TUE/WED NEXT WEEK...MEDIUM.
BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* WEST WINDS BETWEEN 260-280 DEG AND SPEEDS HOVERING ARND 12-14KT
WITH GUSTS TO 18KT THRU 00Z...THEN STEADILY DIMINISHING TO ARND
10-12KT.
* WINDS TURN SOUTHWESTERLY EARLY WED.
BEACHLER
//DISCUSSION...UPDATED 18Z...
VISIBLE IMAGERY THIS AFTERNOON SHOWS VERY MINIMAL CLOUD COVER
ACROSS THE REGION...WITH THE EXCEPTION OF LAKE MICHIGAN AND POINTS
DOWNSTREAM OF THE LAKE. OTHERWISE VFR CONDS LOOK TO PREVAIL
THROUGH AT LEAST THE NEXT 24 HOURS AND POSSIBLY LONGER. HIGH
PRESSURE POSITIONED TO THE SOUTHWEST OF THE REGION WILL KEEP WINDS
FROM THE WEST THROUGH THIS EVENING. THEN THIS AREA OF HIGH
PRESSURE WILL DRIFT SOUTHEAST...ALLOWING WINDS TO BACK TO THE
SOUTHWEST LATE TONIGHT/EARLY WED MORNING. BETTER MIXING THIS
AFTERNOON SHOULD ALLOW OCCASIONAL GUSTS TO 18KT TO
DEVELOP...HOWEVER ONCE THE SUNSETS THESE GUSTS SHOULD QUICKLY
DIMINISH. EXPECT NEAR CLOUDLESS SKIES TO REMAIN THROUGH
TONIGHT...WITH THE EXCEPTION OF A FEW CIRRUS CLOUDS ARND 20KFT
AGL. THEN FOR WED IT APPEARS TO BE A SIMILAR SETUP...HOWEVER WINDS
WILL BE FURTHER SOUTHWEST AND OCCASIONAL GUSTS TO 20-22KT
MIDDAY/EARLY WED AFTN.
BEACHLER
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* HIGH CONFIDENCE IN WIND DIR/SPEED/GUSTS...MEDIUM CONFIDENCE ON
TIMING OF GUSTS DROPPING OFF EARLY THIS EVENING.
* HIGH CONFIDENCE IN ALL OTHER FORECAST ELEMENTS.
BEACHLER
//OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z...
WEDNESDAY NIGHT...VFR.
THURSDAY...SNOW LIKELY...LIGHT ACCUMULATION PSBL. MVFR/IFR PSBL.
FRIDAY THROUGH SATURDAY...CHANCE OF SNOW. MVFR/IFR PSBL.
SUNDAY THROUGH MONDAY...VFR.
BMD
&&
.MARINE...
212 PM CST
A FEW LOW END GALE FORCE GUSTS AROUND 35 KT ARE EXPECTED ACROSS THE
NORTH END OF THE LAKE THROUGH THIS EVENING. HOWEVER...DUE TO THE
RELATIVELY SHORT DURATION...I DO NOT PLAN ON A HEADLINE FOR THESE
WINDS. I WILL CONTINUE THE MENTION OF OCCASIONAL GALE FORCE GUSTS
THROUGH THE EVENING FOR THE NORTH HALF MAFOR.
THE WINDS WILL BECOME SOUTHWESTERLY ACROSS THE LAKE LATER WEDNESDAY
AS A SURFACE TROUGH OF LOW PRESSURE TRACKS ACROSS THE UPPER MIDWEST.
THIS TROUGH OF LOW PRESSURE WILL CREATE A STRONGER PRESSURE GRADIENT
ACROSS THE LAKE WEDNESDAY NIGHT INTO THURSDAY AS IT COMBINES WITH
HIGH PRESSURE ACROSS THE ATLANTIC COAST. OVERALL...THIS WILL LIKELY
RESULT IN SOUTHWESTERLY GALES TO 40 KT...WITH 45 KT GALES
POSSIBLE...DURING THIS TIME. THE GALE WATCH WILL BE UPGRADED TO A
GALE WARNING. THE TROUGH OF LOW PRESSURE/COLD FRONT WILL MOVE OVER
THE LAKE BY EARLY THURSDAY EVENING...AND THIS WILL BRING AN END TO
THE GALES AND CAUSE THE WINDS TO BECOME WESTERLY AGAIN INTO FRIDAY.
I ADDED SOME FREEZING SPRAY TO THE FORECAST FOR WEDNESDAY NIGHT
DURING THE GALE EVENT. HOWEVER...IT DOES NOT APPEAR THIS WILL BE A
MAJOR FREEZING SPRAY EVENT AS AIR TEMPERATURES SHOULD BE WARMING
INTO THE MID AND UPPER 20S.
KJB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...WIND CHILL ADVISORY...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
ILZ011-ILZ012-ILZ013-ILZ014-ILZ020-ILZ022 UNTIL 9 AM
WEDNESDAY.
IN...WIND CHILL ADVISORY...INZ001-INZ002 UNTIL 9 AM WEDNESDAY.
LM...GALE WARNING...LMZ080-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...8 PM WEDNESDAY TO 6 PM
THURSDAY.
HEAVY FREEZING SPRAY WARNING...LMZ080-LMZ261-LMZ362-LMZ364-
LMZ366-LMZ563-LMZ565-LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-
LMZ777-LMZ779-LMZ868-LMZ870-LMZ872-LMZ874-LMZ876-LMZ878
UNTIL 4 AM WEDNESDAY.
GALE WARNING...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-LMZ567-
LMZ868...8 PM WEDNESDAY TO 3 PM THURSDAY.
SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 10 PM THURSDAY.
&&
$$
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FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
National Weather Service Lincoln IL
259 PM CST Tue Jan 28 2014
.DISCUSSION...
ISSUED 259 PM CST Tue Jan 28 2014
Plenty of challenges with this forecast package, as we trade the
recent bitterly cold conditions for a warmer, but active weather
pattern in the extended.
SHORT TERM...Tonight through Friday
One more night of very cold weather is anticipated tonight, as
clear skies and light winds allow overnight lows to drop into the
single digits, with a few spots north of I-74 possibly dipping
below zero. As upper heights rise and winds become southwesterly,
a marked warming trend will get underway on Wednesday with high
temperatures reaching the middle to upper 20s. Even warmer weather
is expected on Thursday when readings climb above the freezing
mark into the middle to upper 30s across all of central and
southeast Illinois.
Models continue to handle the approach of the next cold front
quite well, with all solutions dropping the boundary through the
KILX CWA Thursday night. As has been advertised for several days,
a few snow-showers will accompany the front although most models
are not depicting much in the way of snow accumulation. Have
introduced POPs northwest of the Illinois River as early as
Thursday morning, with low chance POPs spreading further southeast
toward the I-70 corridor by evening. Given lack of deep moisture
and surface temps AOA freezing, am expecting little or no
accumulation during the day Thursday. Aside from the GFS, most
models show light precip fizzling out across the area Thursday
night. Will continue to carry just a slight chance POP with
negligible accumulation.
Things get a little more difficult on Friday, as model solutions
regarding position of frontal boundary begin to diverge. GFS
continues to push front further south into Kentucky while
ECMWF/GEM stall it further north across south-central Illinois.
Prefer the ECMWF/GEM consensus at this point, so will go dry
Friday morning followed by increasing POPs by afternoon. With low
pressure developing and riding along the front, an overrunning
precip event is expected late Friday afternoon through Saturday
morning. With models in poor agreement concerning exact location
of baroclinic zone, thermal profiles are still very much in
question as well. Think warm layer aloft will be strong enough to
warrant at least a mention of mixed precip Friday night across the
S/SE CWA. Will carry a snow/sleet mix along and south of a
Champaign to Jacksonville line for now, but this will likely need
to be adjusted or freezing rain added if further north/warmer
solution pans out. Snow accumulations will generally be between 1
and 3 inches, with the lowest amounts across the far south where
mixed precip is most likely.
LONG TERM...Saturday through Tuesday
First system pulls out Saturday afternoon, followed by cool/dry
weather for Sunday and Monday. After that, attention turns to
approaching southwest flow system early next week. Models are in
poor agreement with the track and timing of the system, with the
GFS being strongest and furthest north, while the ECMWF is weaker
and further south. GEM mirrors the ECMWF track, but is about 12
hours slower. Given so many discrepancies, its hard to pin down
precip types and amounts. At this point, will trend toward the
ECMWF/GEM, spreading snow into the area Monday night into Tuesday.
Will have to keep a close eye on thermal profiles, as even these
more southern models suggest mixed phase precip possible across the
S/SE CWA.
Barnes
&&
.AVIATION...
ISSUED 1127 AM CST Tue Jan 28 2014
Starting to see some stratocumulus developing around 2500 feet, as
hinted at by earlier model runs. Would not be surprised to see
some brief ceilings by mid afternoon, although the RAP model
suggests this would be more likely around KBMI-KDEC eastward, so
have removed the TEMPO MVFR ceilings further west. Westerly winds
continue to gradually become more southwest as high pressure sinks
southward. These will begin to pick up a bit more toward midday
Wednesday, as the pressure gradient starts to tighten ahead of the
next storm system to the northwest.
Geelhart
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS CHICAGO/ROMEOVILLE IL
1133 AM CST TUE JAN 28 2014
.DISCUSSION...
1130 AM CST
HAVE CONVERTED THE WIND CHILL WARNING THAT WAS IN EFFECT UNTIL WED
MORNING TO A WIND CHILL ADVISORY FOR FORECAST WIND CHILL VALUES
OF -20 TO -25...WITH -25 TO -30 IN PARTS OF MAINLY NORTH CENTRAL
IL.
A BITTERLY COLD MORNING WITH NEGATIVE DOUBLE DIGIT AIR
TEMPERATURES ACROSS ALMOST THE ENTIRE CWA...WITH -19 AT OUR COOP
OBSERVER IN MARENGO OBSERVING THE COLDEST. THE ARCTIC HIGH WILL
CONTINUE TO SLIDE SOUTHEAST KEEPING A PRESSURE GRADIENT OVER THE
AREA. WINDS HAVE GRADUALLY INCREASED AND SHOULD SEE THAT PERSIST
INTO AFTERNOON...BUT TEMPERATURES WILL OFFSET THAT MORE SO
ALLOWING WIND CHILLS TO CONTINUE TO CLIMB. WITH WIND CHILL READINGS
ABOVE WARNING CRITERIA /-30/ ALREADY AND TEMPERATURES NOT FORECAST
TO DROP ANYWHERE NEAR AS QUICKLY THIS EVENING AS THEY DID LAST
NIGHT...THUS ALLOWING WIND CHILLS MORE OF -20 TO -28...HAVE GONE
AHEAD WITH THE ADVISORY.
ONLY OTHER ADJUSTMENT WAS TO BUMP UP TEMPS A DEGREE OR SO...WITH A
FEW DEGREES IN THE FAR SOUTHERN CWA WHERE THE LACK OF SNOW COVER
APPEARS TO BE INFLUENCING TEMPS. AT 11 AM IT WAS 3 IN PONTIAC...4
IN LACON...AND 7 IN PEORIA AND CHAMPAIGN ALREADY. THAT WARMTH
/ODD WE CALL THAT WARMTH NOW/ SHOULD EXPAND ACROSS THE FAR SOUTHERN
FORECAST AREA THIS AFTERNOON.
MTF
&&
.PREV DISCUSSION...
335 AM CST
THE GOOD NEWS...THE DEEP FREEZE WILL DEPART BY WEDNESDAY.
THE BAD NEWS...ESPECIALLY FOR ANYONE TIRED OF ALL OF THE SNOW THIS
SEASON...THE MILDER PATTERN WILL FEATURE MORE CHANCES FOR
ACCUMULATING SNOW. THURSDAY WILL BE THE NEXT OPPORTUNITY...FOLLOWED
BY FRIDAY INTO SATURDAY.
WATER VAPOR IMAGERY EARLY THIS MORNING SHOWS EVER PRESENT HIGHLY
AMPLIFIED UPPER PATTERN ACROSS NORTH AMERICA...FEATURING EVER PRESENT
TROUGH TO THE EAST AND ANOMALOUS RIDGING UP TO AND NORTH OF ALASKA.
BEGINNINGS OF PATTERN CHANGE IN THE WEST ARE STARTING TO TAKE SHAPE
HOWEVER...AS JET STREAM INTO THE PAC NW IS FINALLY BREAKING THROUGH
THE WESTERN RIDGE.
AT THE SURFACE...ARCTIC HIGH PRESSURE IS CENTERED OVER WEST CENTRAL
ILLINOIS. DESPITE A GOOD RADIATIONAL COOLING SET-UP...TEMPERATURES
HAVE NOT COOLED AS MUCH AS EXPECTED. ITS POSSIBLE THAT IN JAN 2009
COLD WAVE REFERENCED YESTERDAY...DEEPER SNOW COVER PRESENT PRIOR TO
THE EVENT ENABLED THE COLDER TEMPERATURES DESPITE SIMILAR THERMAL
PROFILES TO THIS MORNING. IT WILL BE CLOSE AS TO WHETHER ORD WILL
COOL ENOUGH TO AT LEAST TIE THE RECORD LOW FOR TODAY AFTER REMAINING
NEARLY STEADY OVERNIGHT. ROCKFORD`S RECORD WILL REMAIN SAFE.
TODAY THROUGH WEDNESDAY NIGHT...THE POLAR VORTEX WILL REMAIN LOCKED
NEAR HUDSON BAY...SO THERE WILL BE LITTLE TO NO MIDLEVEL HEIGHT
CHANGES AND ACTUALLY NO TEMPERATURE ADVECTION. 850 MB TEMPS SAMPLED
AT -26 C AT ILX AND -24C AT DVN DID WARM A FEW DEGREES
OVERNIGHT...BUT 850/925 MB TEMPS WILL REMAIN STEADY IN LOW -20SC
TODAY. CONSIDERING MAX TEMPERATURES YESTERDAY WERE A BIT HIGHER THAN
EXPECTED...FELT COMFORTABLE GOING WITH HIGHS IN THE POSITIVE SINGLE
DIGITS ACROSS THE CWA..."MILDEST" IN THE SOUTHERN CWA WHERE THERE IS
THE LEAST SNOW COVER AND COLDEST IN THE NORTH. WIND CHILL VALUES
WILL START THE DAY NEAR -30 BUT THEN WILL LIKELY STAY ABOVE WARNING
CRITERIA THROUGH TONIGHT CWA WIDE. THEREFORE...WILL PASS ON
RECOMMENDATION TO DAY SHIFT CONVERT EXISTING WARNING AFTER 18Z TO
AN ADVISORY.
WARM ADVECTION WILL COMMENCE ALOFT TONIGHT...THOUGH WINDS SHOULD BE
LIGHT ENOUGH TO ALLOW TEMPERATURES TO DROP SOME. CONSIDERING LOW
TEMPERATURES WERE WARMER THIS MORNING THAN ANTICIPATED...RAISED MIN
T A FEW DEGREES. WIND CHILL VALUES WILL REMAIN IN -20 TO -30 RANGE
NORTH OF KANKAKEE RIVER UNTIL WEDS MORNING. ON WEDNESDAY...AS A
CLIPPER SYSTEM MOVES ALONG THE CANADIAN BORDER AND HIGH PRESSURE
SLIDES FURTHER SOUTHEAST...BREEZY SOUTHWEST FLOW AND WAA WILL ENABLE
TEMPS TO WARM TO THE UPPER TEENS AND LOW 20S UNDER PLENTY OF
SUNSHINE...WITH A FEW MID 20S EXPECTED IN CENTRAL IL. DESPITE THE
BREEZE...THESE READINGS WILL FEEL LIKE A HEAT WAVE. CLOUDS WILL
INCREASE WEDNESDAY NIGHT IN ADVANCE OF MIDLEVEL SHORTWAVE AND COLD
FRONT TRAILING FROM CLIPPER SYSTEM. TIGHTENING PRESSURE GRADIENT
WILL INCREASE SSW WINDS. THEREFORE...EXPECT TEMPERATURES TO RISE
OVERNIGHT.
THURSDAY THROUGH THURSDAY NIGHT...GOOD WARM ADVECTION AND MODEST
ISENTROPIC ASCENT AHEAD OF COLD FRONT...PLUS PVA ASSOCIATED WITH
MIDLEVEL SHORT WAVE AND LEFT EXIT REGION OF JET SHOULD COMBINE TO
RESULT IN A BAND OF SNOW DEVELOPING. THIS BAND WILL LIKELY PIVOT IN
AHEAD OF THE FRONT FROM THE MORNING TO MID DAY ACROSS NORTH CENTRAL
ILLINOIS AND THROUGH THE REMAINDER OF THE AREA DURING THE AFTERNOON
HOURS. FORCING PARAMETERS ARE BEST NORTH OF I-80 WHERE MODEL
SOUNDINGS SHOW A 3 HOUR PERIOD OR SO OF GOOD COLOCATION OF OMEGA AND
SATURATION THROUGH DGZ. THEREFORE I INCREASED POPS TO LIKELY RANGE
THERE AND IF SIGNAL REMAINS CONSISTENT TODAY...POPS SHOULD BE ABLE
TO BE RAISED FURTHER. MAINTAINED SLIGHT TO LOW CHANCE POPS DURING
THE EVENING DUE TO SOME TIMING UNCERTAINTY IN THE GUIDANCE.
EXPECTED SNOW BAND SHOULD BE PROGRESSIVE AS ALLUDED TO ABOVE...AND
WITH TEMPERATURES WARMING TO UPPER 20S TO AROUND 30...RATIOS
SHOULD BE AVERAGE. LOOKING AT POTENTIAL FOR 1 TO 2 INCH SNOWFALL
ACCUMULATIONS NORTH OF I-80 AND LESS THAN AN INCH TO THE SOUTH.
HOW MUCH THE SNOW IS ABLE TO BE BLOWN AROUND IS IN QUESTION...BUT
STRONG SOUTH-SOUTHWEST WINDS GUSTING UP TO 35 MPH ADD CONCERN FOR
FURTHER VISIBILITY REDUCTIONS IN BLOWING SNOW. COLDER AIR WILL
FILTER BACK INTO THE AREA BEHIND THE COLD FRONT THURSDAY NIGHT.
FRIDAY THROUGH MONDAY...
00Z ECMWF AND CANADIAN REMAINED CONSISTENT IN DEVELOPING SNOW FROM
INVERTED TROUGH STRETCHING NORTHEAST FROM LOW PRESSURE OVER THE
SOUTHERN PLAINS DURING FRIDAY...FOCUSED INTO SOUTHERN CWA.
HOWEVER...TIMING OF PRECIP OVERSPREADING THE REMAINDER OF THE CWA
SLOWED SOME TO MAINLY FRIDAY EVENING. THE LOW PRESSURE AREA THEN
EVOLVES NORTHEAST THROUGH OR NORTH OF THE OHIO VALLEY ON SATURDAY.
GFS KEPT PREVIOUS IDEA OF HIGH PRESSURE OVER AREA FRIDAY INTO FRIDAY
EVENING...BUT THEN DID TREND TOWARD OTHER MODELS IN SURFACE LOW
TRACKING TO OHIO VALLEY ON SATURDAY.
THE CURRENT FAVORED LOW PRESSURE TRACK IS A DECENT ONE FOR
ACCUMULATING SNOW IN THE AREA. OF NOTE...HOWEVER...IS
STRENGTHENING WAA IN WSW FLOW ALOFT...WHICH COULD INTRODUCE PTYPE
ISSUES TO SOUTH OF I-80. THE ECMWF IS MOST AGGRESSIVE WITH WARMING
AT SURFACE AND ALOFT ON ITS CURRENT RUN. WITH STILL SOME TIME FOR
CHANGES IN THIS OVERALL EVOLUTION GIVEN FAIRLY LARGE ENSEMBLE
SPREAD...WILL KEEP CHANCE POPS GOING INTO MIDDAY
SATURDAY...DIMINISHING DURING AFTERNOON AS SYSTEM LOOKS TO PULL
AWAY. ADDED A CHANCE OF SLEET INTO GRIDS FOR SOUTH OF I-80 DUE TO
P-TYPE CONCERNS AND ZR MAY BECOME A ISSUE DEPENDING ON HOW
AGGRESSIVE WARMING IS...THOUGH ANY AREAS THAT MIX SHOULD CHANGE
BACK TO SNOW AS COLDER AIR FILTERS IN ON BACKSIDE OF SYSTEM. THIS
PERIOD WILL CONTINUE TO BE OF INTEREST IN COMING DAYS AS POTENTIAL
EXISTS FOR MORE OF A PROLONGED PERIOD OF ACCUMULATING SNOW/WINTER
PRECIP. THE REST OF NEXT WEEKEND SHOULD THEN BE DRY.
AS ALLUDED TO YESTERDAY MORNING...WE WILL BE WATCHING FOR ANOTHER
POTENTIALLY STRONGER SYSTEM IN ACTIVE SOUTHWEST FLOW EARLY TO MID
NEXT WEEK AS PATTERN TRANSITIONS TO A NEGATIVE PNA TYPIFIED BY A
WESTERN TROUGH AND SOUTHEASTERN RIDGE.
RC
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* NONE
BMD/BEACHLER
//DISCUSSION...UPDATED 12Z...
QUIET WEATHER ON TAP FOR TODAY WITH PRIMARILY VFR CONDITIONS AND
WESTERLY WINDS. HIGH PRESSURE LIES SOUTH OF THE TERMINALS THIS
MORNING AND WILL GRADUALLY SHIFT EAST THROUGH THE DAY ALLOWING WINDS
TO BACK SLIGHTLY THROUGH THE PERIOD FROM A NEAR DUE WEST THIS
MORNING TO A WSW THIS AFTERNOON. WINDS WILL BEGIN TO GUST TO AROUND
20 KT THIS AFTERNOON AND SHOULD DIMINISH THIS EVENING. COLD AIR
STRATOCU IS EXPECTED TO DEVELOP THIS AFTERNOON 020-025...THOUGH
COVERAGE SHOULD REMAIN FEW-SCT.
BMD
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* HIGH CONFIDENCE IN ALL FORECAST ELEMENTS
BMD/BEACHLER
//OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z...
WEDNESDAY NIGHT...VFR.
THURSDAY...SNOW LIKELY...LIGHT ACCUMULATION PSBL. MVFR/IFR PSBL.
FRIDAY THROUGH SATURDAY...CHANCE OF SNOW. MVFR/IFR PSBL.
SUNDAY THROUGH MONDAY...VFR.
BMD
&&
.MARINE...
255 AM CST
TWO SEPARATE LOW CENTERS LIE OVER QUEBEC THIS MORNING WHILE BROAD
HIGH PRESSURE STRETCHES FROM THE NORTHERN PLAINS INTO THE OHIO
VALLEY. THIS LEAVES LAKE MICHIGAN UNDER A MODERATE WESTERLY GRADIENT
WITH 30 KT WINDS EXPECTED THROUGH THE DAY TODAY. ONE OF THE LOWS
WILL DRIFT SOUTH OVER HUDSON BAY TONIGHT TIGHTENING THE GRADIENT
FURTHER AND MAY RESULT IN A SHORT WINDOW OF GALE FORCE GUSTS OVER
PRIMARILY NORTHERN PORTIONS OF THE LAKE. WILL NOT HOIST A GALE
WARNING THINKING IT WILL BE SHORT-LIVED AND NOT WIDESPREAD...BUT WILL
INCLUDE OCCASIONAL GALE WORDING IN THE MAFOR/GLF. ANOTHER LOW WILL
PUSH EAST ACROSS THE CANADIAN PRAIRIES MIDWEEK WITH GALES APPEARING
LIKELY ACROSS THE ENTIRE LAKE FOR A PERIOD WEDNESDAY NIGHT INTO
THURSDAY. HIGH PRESSURE WILL BUILD ACROSS THE UPPER MID WEST LATE IN
THE WEEK AND SHOULD ALLOW A BRIEF LULL IN THE WINDS FRIDAY AND
SATURDAY.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...WIND CHILL ADVISORY...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
ILZ011-ILZ012-ILZ013-ILZ014-ILZ020-ILZ022 UNTIL 9 AM
WEDNESDAY.
IN...WIND CHILL ADVISORY...INZ001-INZ002 UNTIL 9 AM WEDNESDAY.
LM...GALE WATCH...LMZ080-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...8 PM WEDNESDAY TO 6 PM
THURSDAY.
HEAVY FREEZING SPRAY WARNING...LMZ080-LMZ261-LMZ362-LMZ364-
LMZ366-LMZ563-LMZ565-LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-
LMZ777-LMZ779-LMZ868-LMZ870-LMZ872-LMZ874-LMZ876-LMZ878
UNTIL 4 AM WEDNESDAY.
GALE WATCH...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-LMZ567-
LMZ868...8 PM WEDNESDAY TO 9 AM THURSDAY.
SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-
LMZ745...6 PM TUESDAY TO 10 PM THURSDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
National Weather Service Lincoln IL
1127 AM CST Tue Jan 28 2014
.DISCUSSION...
ISSUED 945 AM CST Tue Jan 28 2014
Double-digit low temperatures last night were limited to the
extreme northern CWA, which still has a snow cover. The remainder
of the forecast area stayed a few degrees warmer than first
thought, which combined with weakening winds, helped to limit wind
chills from getting out of hand. Have canceled the wind chill
headlines except along/north of I-74, where wind chills are still
around -15 or colder, including -21 at Bloomington. This area may
be able to be canceled as well soon, depending on what the 10 AM
observations show.
Otherwise, high pressure ridging eastward from the central Plains
will slip southward today, allowing winds to pick up a bit.
Temperatures expected to reach double digits in most of the CWA
except perhaps parts of the far northern CWA.
Geelhart
&&
.AVIATION...
ISSUED 1127 AM CST Tue Jan 28 2014
Starting to see some stratocumulus developing around 2500 feet, as
hinted at by earlier model runs. Would not be surprised to see
some brief ceilings by mid afternoon, although the RAP model
suggests this would be more likely around KBMI-KDEC eastward, so
have removed the TEMPO MVFR ceilings further west. Westerly winds
continue to gradually become more southwest as high pressure sinks
southward. These will begin to pick up a bit more toward midday
Wednesday, as the pressure gradient starts to tighten ahead of the
next storm system to the northwest.
Geelhart
&&
.PREV DISCUSSION...
ISSUED 330 AM CST Tue Jan 28 2014
Will continue the wind chill warning NE counties and wind chill
advisory SW counties this morning, though will likely be able to
cancel early and will be on lower end of the criteria (wind chill
warning 25F below zero, wind chill advisory 15F below zero). Lack
of snow pack expect far northern 3 counties of Knox, Stark and
Marshall keeping temps from getting as cold with zero to 6 below
zero north of I-70 and zero to 3F from I-70 south. Wind chills in
the single digits and teens below zero except 24F below zero at
Bloomington. NW winds less than 10 mph early this morning.
00Z models are in fair agreement next few days and using a blend.
Models and then diverge during the weekend into early next week
as we get into more of a SW upper level flow and stayed close to
AllBlend data. Bitter cold temperatures during mid week modify late
this weekend into early next week. Dry weather expected into early
Thursday, then rather unsettled weather pattern expected from
Thursday afternoon into next week.
SHORT TERM...Today through Thursday night
1035 mb arctic high pressure over northern MO and ridging into
central IL early this morning was providing mostly clear skies and
lighter NW winds. More mid/high clouds over southern MO/IL and south.
High pressure drifts into mid MS river valley this evening while strong
upper level trof stays over the region. This could generate
scattered clouds today similar to yesterday along with cold highs
in the 7-15F range with coldest readings from I-74 NE. Wind chills
will modify during late morning and afternoon to above advisory
criteria and then fall back down tonight with wind chills near 15F
below zero edging back south toward I-74 later tonight into mid
morning Wed as surface temps slip to around zero or a bit colder
NE counties. A wind chill advisory may be needed again NE counties
during that time but for now will hold off as temps not looking as
cold as earlier thought due to lack of snow pack plus winds do not
pick up until later Wed morning/afternoon.
High pressure settles into the mid Atlantic states by Wed evening
and increasing SW breezes Wed afternoon into Thu to modify temps.
Highs Wed in the mid to upper 20s with areas SW of Springfield in
the lower 30s. Highs Thursday back to normal in the low to mid 30s.
Low pressure moving east across southern Canada pushes a cold
front SE through IL Thu evening. Have chance of light snow mainly
northern areas Thu afternoon and evening with a dusting to half
inch at best, perhaps up to 1 inch north of Peoria, and little or
no snow over SE IL, maybe just a chance of flurries.
LONG TERM...Friday through Monday
Better chance of light snow from Friday, Friday night into Saturday
as southern stream system moves along frontal boundary to our SE
and spreads light snow chances into central IL with mixed precipitation
possible in southeast IL Fri afternoon and Friday night. Precipitation
to diminish from the west during Saturday and could see a few
inches of snow accumulations north of I-70. 1032 mb high pressure
builds into IL by dawn Sunday with dry weather returning Saturday
night and Sunday and likely staying dry into Sunday night. Temps
cool a bit during the weekend behind the late week weather system.
Highs Sat range from mid 20s north to mid to upper 30s southeast
of I-70. Highs Sunday in the low to mid 20s from I-72 north and
upper 20s and lower 30s south. Next best chance of precipitation
appears to be later Monday night into Tue as another southern
stream storm system ejects NE from the southern plains.
07
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS TOPEKA KS
328 AM CST Tue Jan 28 2014
.SHORT TERM...(Today and Tonight)
Issued at 326 AM CST TUE JAN 28 2014
Early this morning surface high pressure stretched across much of
the Northern and Central Plains, resulting in light or calm winds
across the area. A broad mid-level trough was in place across much
of the central and eastern U.S., with an embedded shortwave trough
pivoting southward over Kansas. Water vapor imagery showed low to
mid-level clouds across much of central and southern Kansas as a
result of this passing wave. This increased cloud cover resulted in
early morning temperatures ranging from the negative single digits
across far northeast Kansas to the single digits across north
central to east central Kansas. With little to no wind present, wind
chills fortunately are not much of an added concern to the already
cold temperatures. Several short-range models are highlighting the
potential for some very light precipitation to skim across north
central and central Kansas this morning as the shortwave trough
passes southeast of the area. Model soundings show a fairly shallow
layer of saturation developing by around sunrise and persisting
through mid to late morning before quickly drying out. This area of
saturation will coincide with some isentropic lift present in the
290K-300K layer, so it may be enough to result in the development of
some scattered flurries.
For today, will see decreasing cloud cover by this afternoon as the
shortwave trough progresses east of the area. With surface high
pressure centered over the region, winds will be light and variable
through the day with temperatures reaching into the 20s. The surface
high will shift south of the area tonight through the overnight
hours with surface winds expected to become light out of the south
by late tonight. As a result, we might approach our overnight low
temperatures closer to around midnight tonight with very little
change in the temperatures through the early morning hours on
Wednesday. Expect low temperatures to drop into the single digits to
low teens with wind chill values ranging from near 0 degrees to the
negative single digits.
.LONG TERM...(Wednesday through Monday)
Issued at 326 AM CST TUE JAN 28 2014
Northwest flow aloft on Wednesday will transition to a west to east
zonal flow across the Central Plains on Thursday. Increasing
pressure gradient across eastern Kansas is forecast ahead of a
deepening low pressure trough in the Western High Plains. South to
southwest winds of 15 to 25 mph with some gusts to around or above
30 mph are expected. Afternoon relative humidity will fall to
between 20 and 25 percent. The low humidity and gusty winds will
elevate the fire danger into the very high category for much of the
area Wednesday afternoon. Highs in the mid and upper 40s still look
on track.
A cold front will approach the northern border by Thursday morning
as a shortwave moves into central Nebraska. This shortwave trough
will move through rather quickly with subsidence Thursday afternoon.
Ascent along with frontogenetic forcing will be focused near the
Nebraska border in the morning and have kept a small chance of snow
for Thursday morning. Temperatures Wednesday night and into Thursday
look to be warmer than guidance. Lower boundary layer will remain
mixed ahead of the front with lows in the upper 20s expected
Wednesday night Highs in the 40s south of the front with upper 30s
near the Nebraska border.
A series of waves will move through the zonal flow from Thursday
through Monday. Thursday night with mid level frontogenetic boundary
across the CWA will bring a small chance of light snow after
midnight. Models show a stronger wave moving across the Northern and
Central Plains Friday into Saturday. Upper level ascent will move
over northern Kansas bringing another chance of some light snow to
the area with little accumulation expected.
Saturday and Sunday looking dry as as high pressure ridge moves into
the eastern Kansas Saturday then moves off to the east during the
day on Sunday. Temperatures will be slightly below normal in the 30s
for highs with teens and 20s for lows. Next chance of more snow
arrives early next week as a wave moves out of the southern Rockies
and across the Southern Plains. ECMWF more robust than the GFS and
will trend toward the ECMWF solution for next Monday. Snow amounts
will be light once again. Models are indicating that a stronger
system will approach the region Tuesday night and Wednesday.
&&
.AVIATION...(For the 06Z TAFs through 06Z Tuesday Night)
Issued at 1101 PM CST MON JAN 27 2014
Main concern is whether brief isentropic lift will be enough for
some light snow to develop across central KS by mid morning. Both
the NAM and RAP show some AC moving in as the lift occurs. At this
point think the snow is more likely to the southwest of MHK.
However can not rule out some flurry activity affecting MHK. Will
also need to watch out for MVFR CIGS. The RAP appears to be the
more aggressive with the lower CIGS. For now have continued with a
VFR forecast thinking the RAP is again overdoing the low RH, but
this will need to be monitored.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Hennecke
LONG TERM...53
AVIATION...Wolters
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1101 PM CST Mon Jan 27 2014
...AVIATION UPDATE...
.SHORT TERM...(This Evening through Tuesday)
Issued at 232 PM CST MON JAN 27 2014
Current 20Z surface analysis shows a ridge of high pressure across
the plains stretching from ND to NE. That ridge will continue to
build southward over the forecast area allowing the winds to become
relatively calm overnight and into tomorrow. Low temperatures in the
morning will range from -0s in far northeast KS to the low 0s
elsewhere with wind chill values ranging from -10 in far northeast
KS to around 0. A weak upper level disturbance will move southeast
out of the northern Rockies tomorrow morning. As that system
approaches central KS there may be enough lift and moisture to
produce flurries across the southwest portion of the forecast area.
Do not expect any accumulations at this time. Elsewhere will remain
quiet with mostly to partly cloudy skies. High temperatures tomorrow
will generally be in the 20s.
.LONG TERM...(Tuesday Night through Monday)
Issued at 232 PM CST MON JAN 27 2014
The upper level flow pattern across the western CONUS will flatten
out to nearly zonal Wednesday into Thursday. One compact short wave
trough will move along the US/Canada border Wednesday night with a
frontal boundary dropping south into KS for Thursday. Ahead of this
storm system, Wednesday will start out quite cool with surface high
pressure shifting slowly south, but south winds will increase quite
a bit during the day with warm advection into the region. Expect
elevated fire danger on Wednesday as Min RH values are currently
forecast near 20% and wind gusts will probably top 30 mph. The
strong winds will likely continue into the overnight hours as well.
Temperatures are expected to cool a bit behind the front on
Thursday, but as the boundary stalls, mid level frontogenesis is
expected to work in conjunction with one or two weak pieces of short
wave energy to produce enough lift to support light precipitation in
an E/W oriented band near the Nebraska border. Any precip developing
in the mid levels will have to overcome quite a bit of dry air, but
there seems to be potential for the lift to have a long residence
time over a localized area which would suggest potential for
saturation and light snow at the surface. Right now, it seems that
any accumulation would be minor and limited to northern KS.
Model guidance suggests another fairly strong upper level system
dropping south out of Canada by late Friday into Saturday. Not
particularly confident in the details of this system, but as the
main upper level ascent skirts the local area, see at least some
potential for light snow showers. Again, this looks like a minimal
accumulation event. Expect the airmass behind the Saturday trough to
be quite dry with near to slightly below normal temperatures.
The weather begins to get rather interesting by the very end of the
forecast period, late Monday into Tuesday of next week. All guidance
is consistent in suggesting that a strong storm system will dive
into the southwestern CONUS by Sunday night. Being so far out, model
run-to-run consistency has been low, but the potential storm track
would be consistent with bringing a healthy fetch of moisture into
the area with a prolonged period of isentropic ascent in advance of
the system followed up by ascent associated more directly with
the upper low itself. Temperatures should be plenty cold for snow in
a broad sector of this storm system. Will need to monitor the Monday
through Wednesday period closely in coming forecasts for winter
weather potential.
&&
.AVIATION...(For the 06Z TAFs through 06Z Tuesday Night)
Issued at 1101 PM CST MON JAN 27 2014
Main concern is whether brief isentropic lift will be enough for
some light snow to develop across central KS by mid morning. Both
the NAM and RAP show some AC moving in as the lift occurs. At this
point think the snow is more likely to the southwest of MHK.
However can not rule out some flurry activity affecting MHK. Will
also need to watch out for MVFR CIGS. The RAP appears to be the
more aggressive with the lower CIGS. For now have continued with a
VFR forecast thinking the RAP is again overdoing the low RH, but
this will need to be monitored.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...Sanders
LONG TERM...Barjenbruch
AVIATION...Wolters
AREA FORECAST DISCUSSION
NWS GRAY ME
947 PM EST WED JAN 29 2014
.SYNOPSIS...
A RIDGE OF HIGH PRESSURE WILL CONTINUE TO BUILD INTO THE NORTHEAST
TONIGHT THEN SLIDE OFF THE COAST ON THURSDAY. A WEAK COLD FRONT
APPROACHES THE REGION FROM THE N ON FRIDAY...AND STALLS OVER THE
REGION SATURDAY...BRING THE THREAT FOR SHOWERS OF SNOW OR RAIN. LOW
PRESSURE WILL TRACK EASTWARD ALONG THE FRONT SATURDAY NIGHT...AND
COULD PRODUCE A PERIOD OF LIGHT SNOW OR RAIN. AS THE LOW MOVES
OFFSHORE ON SUNDAY...IT WILL DRAG THE COLD FRONT ACROSS THE
AREA...WITH HIGH PRESSURE BUILDING IN EARLY NEXT WEEK.
&&
.NEAR TERM /TONIGHT/...
945PM UPDATE...
NO SIGNIFICANT CHANGES TO THE FORECAST AS LOW TEMPERATURE FORECAST
SEEMS ON TRACK. A FEW CLOUDS IN THE MOUNTAINS WITH ONLY A SLIGHT
CHANCE OF SNOW SHOWERS. DRY AND COLD ELSEWHERE.
515PM UPDATE...
HAVE MADE A FEW MINOR ADJUSTMENTS TO SKY COVER AND POP FORECAST.
VERY LOW CHANCE OF SNOW SHOWERS TONIGHT IN THE MOUNTAINS WHERE
WESTERLY WINDS CAUSE UPSLOPE CONDITIONS IN COORDINATION WITH A
PASSING TROUGH. OTHERWISE CLEAR SKIES EXPECTED.
ORIGINAL DISCUSSION...
LOW CLOUDINESS AND SCATTERED SNOW SHOWERS WILL CONTINUE TO MAKE
THEIR WAY EASTWARD TOWARDS THE MOUNTAINS THIS EVENING. THERE IS
LIMITED MOISTURE TO WORK WITH...HOWEVER THE PASSAGE OF AN UPPER
LEVEL TROUGH SHOULD BE SUFFICIENT FOR THIS LIGHT PRECIPITATION.
LATEST HRRR RUN KEEPS MOST OF THE LIGHT PRECIPITATION WEST OF OUR
FORECAST AREA.
EXPECT LOWS TO BE BELOW ZERO IN ALL AREAS EXCEPT THE COASTLINE.
WITH A LIGHT WESTERLY BREEZE...WIND CHILL VALUES WILL APPROACH 20
BELOW IN A FEW SPOTS IN THE MOUNTAINS TONIGHT. THIS WILL BE
ISOLATED...SO WE WILL NOT BE ISSUING WIND CHILL ADVISORIES.
&&
.SHORT TERM /THURSDAY AND THURSDAY NIGHT/...
HIGH PRESSURE WILL BEGIN TO SLIDE OFF THE COAST ON THURSDAY...
ALLOWING FOR A GRADUAL WARM UP EMBEDDED WITHIN A BROAD REGION OF
WARM AIR ADVECTION. BY THURSDAY NIGHT...THE APPROACH OF A WEAK
FRONT OVER SOUTHERN CANADA WILL BE SUFFICIENT TO TRIGGER SCATTERED
SNOW SHOWERS IN THE MOUNTAINS ONCE AGAIN. THESE SNOW SHOWERS WILL
BE RELATIVELY LIGHT AS THE ATMOSPHERE WILL REMAIN RELATIVELY DRY.
IT WILL FEEL MUCH MILDER ON THURSDAY AND THURSDAY NIGHT AS
TEMPERATURES SLOWLY CREEP UP TOWARDS NEAR NORMAL LEVELS.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
THE OVERALL +PNA PATTERN AT 500 MB CONTINUES...WITH MODELS
CONTINUING TO AMPLIFY THE RIDGE OVER THE EASTERN PACIFIC INTO
ALASKA. THIS WILL KEEP THE MEAN TROUGHINESS IN PLACE OVER EASTERN
NORTH AMERICA...WITH WEAK SYSTEMS EVERY DAY OR TWO...BUT NO BIG
STORMS IN SIGHT. THE RIDGING REACHING POLEWARD ACROSS ALASKA
WILL CUT OFF THE COLDEST HEMISPHERIC AIR...HOLDING OVER SIBERIA
INTO NEXT WEEK. SO...IT LOOKS LIKE WILL BE TRENDING TO A PERIOD
WITH TEMPERATURES RUNNING NEAR TO SLIGHTLY ABOVE NORMAL THIS
WEEKEND AND INTO THE MIDDLE OF NEXT WEEK.
FRIDAY SHOULD SEE A FAIR AMOUNT OF CLOUDS AS WE GET INTO SOME
STAGNANT FLOW AT LOW LEVELS... AND THE MID-HIGH LEVEL FLOW BECOMES
WELL LINED UP. A WEAKENING 500 MB WAVE TRACKS JUST TO OUR NORTH
LATE FRIDAY AND FRIDAY NIGHT. THIS WILL PUSH A SURFACE COLD FRONT
SOUTH INTO NORTHERN MAINE... WHERE IT LOOKS TO STALL THROUGH
SATURDAY... WHICH COULD PRODUCE A FEW SNOW SHOWERS... MAINLY IN
THE NORTH. A WEAK LOW WILL TRACK EAST ALONG THE FRONT LATE
SATURDAY INTO EARLY SUNDAY... WHICH IS THE BETTER CHANCE FOR
PRECIPITATION... WHICH WOULD BE MAINLY SNOW... EXCEPT SOME RAIN
MAY BE POSSIBLE ALONG THE IMMEDIATE COAST. IT SHOULD START TO
CLEAR OUT SUNDAY AFTERNOON... WITH SOME COOLER AIR IN FOR EARLY
NEXT WEEK... BUT SHOULD REMAIN NEAR NORMAL. NEXT CHANCE FOR
PRECIPITATION LOOKS TO BE TUESDAY NIGHT INTO WEDNESDAY...AS
SURFACE LOW TRACKS QUICKLY TO THE SOUTH.
&&
.AVIATION /22Z WEDNESDAY THROUGH MONDAY/...
SHORT TERM...SOME LOW CLOUDINESS WILL CONTINUE TO ADVANCE INTO THE
MOUNTAINS THIS EVENING. THIS WILL ALLOW FOR SCATTERED SNOW SHOWERS
FOR THE BEGINNING OF THE NIGHT...ALONG WITH MVFR CONDITIONS.
ELSEWHERE...VFR IS EXPECTED THROUGH THURSDAY. ANOTHER WEAK WEATHER
DISTURBANCE WILL BRING MVFR CONDITIONS TO THE MOUNTAINS THURSDAY NIGHT.
LONG TERM...MAINLY VFR ON FRIDAY...THEN POTENTIAL FOR MVFR CEILINGS
FRIDAY NIGHT INTO SATURDAY NIGHT... WITH SOME IFR OR LOWER IN SNOW
SATURDAY NIGHT. CONDITIONS IMPROVE TO VFR SUNDAY AFTERNOON...
PERSISTING THRU MONDAY.
&&
.MARINE...
SHORT TERM...WITH GRADIENT INCREASING AND COLD AIR ADVECTION
CONTINUING...WILL LEAVE SCAS UP FOR THE OUTER WATERS.
LONG TERM...SCA WINDS/SEAS DIMINISH ON FRIDAY... WITH FAIRLY
QUIET CONDITIONS FOR THE MIDDLE OF WINTER INTO EARLY NEXT WEEK.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 AM EST THURSDAY FOR ANZ150-152-
154.
&&
$$
NEAR TERM UPDATE... KIMBLE
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
413 PM EST TUE JAN 28 2014
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 412 PM EST TUE JAN 28 2014
WATER VAPOR LOOP AND RUC ANALYSIS REVEALS PERSISTENT PATTERN OF A
STRONG MID/UPPER LEVEL RIDGE ALONG THE W COAST OF N AMERICA WITH A
BROAD DEEP TROF DOWNSTREAM OVER ERN NAMERICA. WITH 850MB TEMPS IN
THE AROUND -25C...LES CONTINUES OFF MAINLY NCNTRL AND ERN LAKE
SUPERIOR WITH A W-WSW WIND FLOW WHERE VIS SATELLITE LOOP AND LATEST
MODIS IMAGE SHOWS THE GREATEST AREA OF OPEN WATER. MUCH OF THE
WESTERN HALF OF THE LAKE LOOKS TO BE ICE-COVERED EXCEPT FOR MAYBE A
NARROW PORTION JUST WEST OF THE KEWEENAW ALTHOUGH WAA MID-HIGH
CLOUDS MOVING IN FROM NORTH OF THE LAKE AHEAD OF SHORTWAVE ROTATING
DOWN FM NRN ONTARIO MAKING IT HARDER TO DISCERN ICE COVERAGE OVER
WEST HALF OF LAKE SUPERIOR THIS AFTERNOON. ALTHOUGH KCMX HAS
REPORTED OCCASIONAL VSBY OF 1/2SM OR LOWER...VSBY LOOKS GOOD ACROSS
MUCH OF THE KEWEENAW BASED ON WEBCAMS. THUS...DECIDED TO CANCEL LAKE
EFFECT ADVISORY ON MORNING UPDATE. AFTERNOON TEMPS HAVE RISEN UP TO
NEAR ZERO OR SLIGHTLY BLO ZERO AS NOTED ON LATEST SFC OBS. WIND
CHILLS AT KCMX ARE STILL SOLIDLY INTO ADVISORY CATEGORY (-30F OR
LOWER) WITH WEST WINDS GUSTING OVER 35 MPH THRU MUCH OF THE DAY.
MUCH OF THE REST OF THE CWA IS JUST ABOVE ADVISORY CRITERIA OF -25F
HEADING INTO THE EVENING HRS.
AS FOR WIND CHILL HEADLINES TONIGHT INTO WED MORNING WILL KEEP
CURRENT WIND CHILL ADVISORIES IN PLACE FOR THE WRN COUNTIES WHILE
ADDING BARAGA AND SRN HOUGHTON COUNTIES...SO COUNTIES FROM BARAGA
AND IRON WESTWARD WILL BE IN ADVISORIES THROUGH 16Z WED. PORTIONS OF
WRN MQT COUNTY COULD REACH WIND CHILL ADVISORY CRITERIA LATE TONIGHT
BUT MOST OF THE COUNTY SHOULD STAY ABV -25F SO DECIDED AGAINST
HEADLINE THERE. ACROSS THE REST OF THE AREA...WIND CHILLS WILL LOWER
INTO THE -20F TO -25F RANGE OR JUST ABV ADVISORY CRITERIA.
COMBINATION OF INCREASING CLOUDS AND WINDS SHOULD PREVENT A BIG FALL
IN TEMPS TONIGHT. EXPECT MIN TEMPS FROM THE SINGLE DIGITS BLO ZERO
ACROSS ALL BUT THE FAR SW CWA NEAR THE WI BDR WHERE LOWS COULD
APPROACH -12F IN A FEW SPOTS.
RELATIVELY WARMER AIR ARRIVING WEDNESDAY WILL ALLOW HIGHS TO RISE IN
THE TEENS ACROSS MUCH OF THE AREA. ALTHOUGH IT MAY FEEL LIKE A
SIGNIFICANT WARM-UP FROM THE RECENT BELOW ZERO HIGHS...NORMAL VALUES
FOR THIS TIME OF YEAR ARE IN THE LOW 20S FOR HIGH TEMPERATURES.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 412 PM EST TUE JAN 28 2014
A MUCH QUIETER PATTERN LOOKS TO BE IN STORE FOR THE END OF JANUARY
AND BEGINNING OF FEBRUARY. THE LARGE AND COLD UPPER TROUGH THAT HAD
BEEN AFFECTING THE REGION OVER THE LAST SEVERAL DAYS WILL HAVE
MOVED EAST AND WEAK RIDGING WILL MOVE THROUGH THE AREA ON
WEDNESDAY. THIS SETUP WILL PLACE A BROAD UPPER TROUGH OVER THE
NORTHERN HALF OF THE CONUS. THE COLDEST AIR WILL REMAIN IN
CANADA...BUT OCCASIONAL CLIPPER SYSTEMS WILL BRING BRIEF PERIODS OF
SNOW AND LAKE EFFECT ALONG WITH SLIGHTLY COOLER TEMPERATURES.
OVERALL THOUGH...TEMPERATURES THROUGH THE LONG TERM PERIOD WILL
REMAIN BELOW NORMAL WITH HIGHS MOST DAYS IN THE TEENS AND LOWS IN
THE SINGLE DIGITS BELOW ZERO.
OUR STREAK OF DAYS AT OR BELOW FREEZING CONTINUES...WITH TODAY BEING
THE 54TH DAY IN A ROW. LOOKING AT LONG TERM ECMWF/GFS ENSEMBLE
DATA...NONE OF THE MEMBERS ARE INDICATING ABOVE FREEZING TEMPS OVER
THE NEXT 10 DAYS AND ONLY A RUN OR TWO NEAR DAY 15. THUS...THERE IS
THE POTENTIAL WE WILL BE NEARING THE RECORD OF 72 DAYS (SET IN
1978-1979) WHEN WE APPROACH THE MIDDLE OF FEBRUARY.
A CLIPPER SYSTEM WILL BE THE FIRST FEATURE OF NOTE FOR THE LONG
TERM FORECAST FOR WEDNESDAY NIGHT INTO THURSDAY MORNING. THIS
CLIPPER WILL BE LOCATED EAST OF LAKE WINNIPEG AT 00Z THURSDAY AND
WILL QUICKLY MOVE TO JAMES BAY BY 18Z THURSDAY. AS THIS OCCURS...IT
WILL DRAG A COLD FRONT ACROSS THE UPPER GREAT LAKES REGION
OVERNIGHT AND DEPART THURSDAY MORNING. THE SOUTHERN SIDE OF THE
FRONT (WHICH AFFECTS MUCH OF THE U.P.) WILL BE A LITTLE MOISTURE
STARVED AND WITH MUCH OF THE FORCING MOVING THROUGH NORTHERN LAKE
SUPERIOR AND SOUTHERN ONTARIO...EXPECT THE QPF AMOUNTS TO BE LIGHT.
WILL NEED TO KEEP AN EYE ON ANOTHER DISTURBANCE MOVING EAST THROUGH
THE PLAINS STATES LATE WEDNESDAY NIGHT AND THE LOWER GREAT LAKES ON
THURSDAY. DEPENDING ON HOW QUICKLY THEY NEAR EACH OTHER THERE COULD
BE AN INCREASE IN QPF AMOUNTS OVER THE EASTERN HALF OF THE CWA.
WILL KEEP THE HIGHEST POPS OVER LAKE SUPERIOR AND EAST TOWARDS
MORNING OVER THE EASTERN U.P. SNOW AMOUNTS SHOULD ONLY BE A DUSTING
OVER THE WEST HALF...BUT IF THE INTENSITY INCREASES OVER THE EASTERN
CWA...AMOUNTS THERE COULD BE IN THE 1-3 INCH RANGE (MUCH OF THE
FORCING/CLOUD IN THE DGZ).
BEHIND THE FRONT...WESTERLY FLOW WILL SETUP AGAIN ACROSS THE U.P.
AS A 850MB TEMPS FALL TO AROUND -16C. THIS IS SUPPORTIVE FOR LAKE
EFFECT SNOW (ALONG WITH MUCH OF THE CLOUD BEING WITHIN THE DGZ) BUT
MODELS ARE INDICATING INVERSION HEIGHTS AROUND 5-6KFT. IN
ADDITION...WITH ICE COVER BUILDING OVER WESTERN LAKE SUPERIOR
CONFIDENCE ON THE AMOUNT OF LAKE EFFECT THAT ACTUALLY OCCURS IS
UNCERTAIN. THEREFORE...WILL CONTINUE HIGH END LIKELY AND LOW
END DEFINITE POPS FOR THE WEST-NORTHWEST WIND LOCATIONS THURSDAY
AFTERNOON/NIGHT. A DISSIPATING HIGH PRESSURE RIDGE MOVING EAST INTO
THE GREAT LAKES REGION ON FRIDAY WILL LEAD TO BACKING WINDS AND
SHIFT THE LAKE EFFECT OFF SHORE FOR ALL BUT THE KEWEENAW PENINSULA.
MODELS COMING INTO BETTER AGREEMENT ON THE HANDLING OF THE NEXT
NORTHERN STREAM WAVE AND THE POTENTIAL DEVELOPMENT OF A WEAK LOW IN
THE PLAINS MOVING THROUGH THE LOWER GREAT LAKES SATURDAY. 12Z
ECMWF/GEM DETERMINISTIC RUNS IN DECENT AGREEMENT WITH THE
TRACK/STRENGTH OF THE LOW AND THE GFS IS STARTING TO COME AROUND
TO IT. THE GENERAL IDEA FROM THE ENSEMBLE MEMBERS IS FAIRLY SIMILAR
TO A GENERAL CONSENSUS OF THE GEM/ECMWF/GFS AND WILL FOLLOW THAT
IDEA. THUS...HAVE INCREASED CLOUD COVER OVER THE AREA FOR SATURDAY
AND WITH THE AREA BEING ON THE NORTHWEST SIDE OF THE SYSTEM...HAVE
SLIGHT POPS OVER MUCH OF THE CWA AND CHANCES ALONG THE LAKE
MICHIGAN SHORE.
BEHIND THE LOW...THERE WILL BE THE POTENTIAL FOR LIGHT
LAKE EFFECT IN THE WESTERLY WIND BELTS THROUGH THE FIRST PART OF
NEXT WEEK. HAVE KEPT CHANCES...ESPECIALLY OVER THE KEWEENAW...DUE
TO THE UNCERTAINTY ON HOW MUCH ICE WILL BE OVER WESTERN LAKE
SUPERIOR.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1241 PM EST TUE JAN 28 2014
VERY COLD AIR SHOULD CONTINUE TO GENERATE SCATTERED LIGHT LAKE EFFECT
SNOW THRU THIS FCST PERIOD AT KCMX...FAVORED BY WESTERLY WINDS.
HOWEVER...EXTENSIVE ICE COVER ON WESTERN LAKE SUPERIOR WILL LIMIT
INTENSITY OF -SHSN. WILL INCLUDE PREVAILING IFR CONDITIONS AT 1SM FOR
VSBY WITH A TEMPO FOR 1/2SM THIS AFTERNOON FOR SHSN AND BLSN. WITH A
PASSING DISTURBANCE...WINDS MAY VEER SLIGHTLY TONIGHT...AND THIS
WILL BRING -SHSN/BLSN BACK TO KCMX THIS EVENING IF -SHSN DO IN FACT
END TODAY. IMPROVEMENT IS EXPECTED LATE TONIGHT IN THE WAKE OF
DISTURBANCE AS DRIER AIR ARRIVES.
AT KIWD/KSAW...VFR CONDITIONS WILL PREVAIL. MIGHT BE A FEW FLURRIES
THIS EVENING...BUT NOT EXPECTING CONDITIONS TO DROP BLO VFR.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 412 PM EST TUE JAN 28 2014
FREEZING SPRAY WILL CONTINUE TO BE A CONCERN THROUGH FRIDAY AS
ARCTIC AIR AND STRONG WINDS CONTINUE OFF AND ON. EXPECT WSW GALES TO
40 KTS OVER E LAKE SUPERIOR FROM LATE THIS AFTERNOON THROUGH TONIGHT
AS WINDS AGAIN SHIFT TO THE W LATE TONIGHT. ANOTHER BRIEF PERIOD OF
S GALES TO 35KTS WILL BE POSSIBLE WEDNESDAY NIGHT OVER THE E.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WIND CHILL ADVISORY UNTIL 11 AM EST /10 AM CST/ WEDNESDAY FOR
MIZ001>004-009-010-084.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST THURSDAY FOR LSZ267.
GALE WARNING UNTIL 7 AM EST WEDNESDAY FOR LSZ266-267.
HEAVY FREEZING SPRAY WARNING UNTIL 1 PM EST FRIDAY FOR LSZ266.
HEAVY FREEZING SPRAY WARNING UNTIL 7 PM EST WEDNESDAY FOR LSZ263-
264.
GALE WARNING UNTIL 10 PM EST THIS EVENING FOR LSZ244-264.
GALE WARNING UNTIL 1 AM EST WEDNESDAY FOR LSZ263.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...VOSS
LONG TERM...SRF
AVIATION...VOSS
MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
504 AM EST TUE JAN 28 2014
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 430 PM EST MON JAN 27 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A SHORTWAVE MOVED THROUGH
THE UPPER GREAT LAKES THIS AFTERNOON ON THE EDGE OF EXPANSIVE POLAR
VORTEX CENTERED ROUGHLY NEAR OR SOUTH OF JAMES BAY. CORE OF THE
COLDEST ARCTIC AIR MOVED THROUGH THE UPPER LAKES THIS AFTERNOON WITH
850 MB TEMPS NEAR -30C. WITH BEST FORCING ASSOC WITH THIS FEATURE
NOW EAST OF THE CWA...LES BANDS ON RADAR OVER ERN LAKE SUPERIOR HAVE
GENERALLY DECREASED IN INTENSITY AND BECOME MORE SPACED APART DUE TO
INFLUX OF DRIER AIR UPSTREAM.
WINDS CONTINUE TO GUSTS AT OR ABOVE 30 MPH OVER THE KEWEENAW AND THE
ERN SHORELINE PRODUCING OCCASIONAL WHITEOUT CONDITIONS IN SNOW AND
BLOWING SNOW. WIND CHILLS CONTINUE IN THE -23 TO -30F RANGE THIS
AFTERNOON. AS TEMPS CONTINUE TO FALL THIS EVENING...EXPECT WIND
CHILLS TO FALL TO THE -30F TO -35F RANGE.
WINDS WILL CONTINUE TO BACK WESTERLY BY LATE EVENING...FOCUSING LES
OVER THE KEWEENAW PENINSULA AND ALSO CLOSE TO THE ERN SHORE FROM
AROUND GRAND MARAIS EASTWARD. POTENTIAL FOR INCREASED LOW-LVL
CONVERGENCE INTO NW UPPER MI DUE TO LAND BREEZE ACTION COULD
ENHANCED LES TONIGHT OVER THE KEWEENAW PENINSULA. SO WILL CONTINUE
TO HIGHLIGHT HIGHER POPS/SLIGHTLY HIGHER ACCUMULATIONS ACROSS THE
KEWEENAW AND FAR ERN SHORELINE AREAS WHERE LES ADVISORIES WILL
CONTINUE INTO THIS EVENING EAST AND INTO TUE MORNING OVER THE
KEWEENAW. STILL...NOT REALLY EXPECTING MORE THAN 1-3 INCHES OF SNOW
DUE TO THE COLD COLUMN OF AIR IN PLACE AND LACK OF A DGZ.
HOWEVER...SNOW WILL CONTINUE TO BE EFFECTIVE IN REDUCING VSBY TO
NEAR ZERO AT TIMES WHERE LES IS OCCURRING.
WITH A FAIRLY TIGHT PRES GRADIENT EXPECTED ACROSS THE AREA
TONIGHT...LOW TEMPS WILL NOT BOTTOM OUT AS MUCH AS ONE WOULD EXPECT
GIVEN ARCTIC AIRMASS IN PLACE BECAUSE A STEADY WIND IS EXPECTED
THROUGH THE NIGHT. IF HIGH PRES WAS CENTERED MORE OVER THE AREA
INSTEAD OF OVER THE PLAINS...TEMPS WOULD PROBABLY PLUMMET TO -40F IN
THE TRADITIONAL COLD SPOTS...BUT THAT WON`T BE THE CASE TONIGHT.
OVERALL...EXPECT MINS GENERALLY IN THE -10F TO -20F RANGE OVER THE
FCST AREA...PERHAPS A FEW DEGREES WARMER OVER THE TIP OF THE
KEWEENAW AND FAR E ALONG LAKE SUPERIOR AND A FEW DEGREES COLDER
ALONG THE WRN INTERIOR ALONG THE WI BORDER. WITH THE WIND...WIND
CHILLS WILL FALL TO -30 TO -45F OVER MUCH OF AREA AND CONTINUE INTO
TUE MORNING. THIS WILL WARRANT CONTINUED WIND CHILL WARNING ACROSS
MOST OF THE AREA WITH WIND CHILL ADVISORIES FAR EAST CLOSER TO LAKE
SUPERIOR.
WINDS CONTINUING TO BACK WEST OR WSW SHOULD PUSH ANY REMAINING LES
OFFSHORE OF THE ERN SHORELINE AREAS BY EARLY TUE AND GRADUALLY PUSH
LES INTO MAINLY KEWEENAW COUNTY OVER THE NW BY TUE AFTERNOON. LOOK
FOR HIGHS GENERALLY ZERO TO 5 BELOW ACROSS MUCH OF THE CWA ON
TUESDAY UNDER CLEAR TO PARTLY CLOUDY SKIES.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 426 PM EST MON JAN 27 2014
A MUCH QUIETER PATTERN LOOKS TO BE IN STORE FOR THE END OF JANUARY
AND BEGINNING OF FEBRUARY. THE LARGE AND COLD UPPER TROUGH
CURRENTLY OVER THE REGION WILL SHIFT EAST ON TUESDAY NIGHT AND
WEDNESDAY ALLOWING WEAK RIDGING TO MOVE OVER THE AREA. THEN...THE
REST OF THE PERIOD WILL SEE A BROAD UPPER TROUGH OVER THE NORTHERN
HALF OF THE CONUS. THE COLDEST AIR WILL REMAIN IN CANADA...BUT
OCCASIONAL CLIPPER SYSTEMS WILL BRING BRIEF PERIODS OF SNOW AND
LAKE EFFECT ALONG WITH SLIGHTLY COOLER TEMPERATURES. OVERALL
THOUGH...TEMPERATURES THROUGH THE LONG TERM PERIOD WILL REMAIN
BELOW NORMAL WITH HIGHS MOST DAYS IN THE TEENS AND LOWS IN THE
SINGLE DIGITS BELOW ZERO.
LAKE EFFECT WILL BE ONGOING IN THE WEST TO SOUTHWEST SNOW BELTS TO
START TUESDAY EVENING...BUT A SURFACE TROUGH ASSOCIATED WITH A
SHORTWAVE MOVING THROUGH NORTHEAST ONTARIO WILL PUSH THROUGH ON
TUESDAY NIGHT. THIS TROUGH WILL BRING ADDITIONAL LOW LEVEL MOISTURE
TO THE AREA AND SHIFT WINDS A LITTLE MORE WESTERLY. BUT AS THIS
OCCURS...IT WILL PRODUCE A COUPLE DETRIMENTAL AFFECTS THROUGH THE
NIGHT INTO WEDNESDAY. ALTHOUGH 875MB TEMPERATURES WILL START OUT
AROUND -24C...THE WARMING ALOFT BEHIND THE FRONT UNDER WESTERLY
WINDS WILL END UP LOWERING INVERSION HEIGHTS THROUGH THE NIGHT.
THIS...COMBINED WITH THE HIGH PRESSURE RIDGE BRINGING DRIER AIR TO
THE REGION ON WEDNESDAY...WILL LEAD TO A QUICK DIMINISHMENT TO THE
LAKE EFFECT FROM WEST TO EAST TUESDAY NIGHT INTO WEDNESDAY MORNING.
IN RESPONSE TO THIS HIGH...A FAIRLY NICE BUT COOL DAY IS
EXPECTED ACROSS THE U.P. ON WEDNESDAY.
THE HIGH WILL QUICKLY SHIFT EAST WEDNESDAY AFTERNOON AND
EVENING...ALLOWING A COLD FRONT (ASSOCIATED WITH A CLIPPER MOVING
EAST THROUGH ONTARIO) TO SWEEP ACROSS THE U.P. WEDNESDAY NIGHT INTO
THURSDAY MORNING. MODELS VARY ON HOW FAR SOUTH THE BEST
FORCING/MOISTURE WILL SINK...SO WILL KEEP POPS AT CHANCE FOR NOW.
MUCH OF THE CLOUD/FORCING WITHIN THE DGZ...SO WOULD EXPECT SNOW
RATIOS TO BE WELL ABOVE CLIMO AND IN THE 20-30 TO 1 RANGE IF SNOW
OCCURS. AT THIS POINT...ONLY HAVE A LIGHT DUSTING TO AN INCH IN
THE FORECAST WITH THE HIGHEST AMOUNTS OVER THE EAST.
BEHIND THE FRONT...WESTERLY FLOW WILL SETUP AGAIN ACROSS THE U.P.
AS A 850MB TEMPS FALL TO AROUND -17C. THIS IS SUPPORTIVE FOR LAKE
EFFECT SNOW (ALONG WITH MUCH OF THE CLOUD BEING WITHIN THE DGZ) BUT
MODELS ARE INDICATING INVERSION HEIGHTS AROUND 5-6KFT.
THEREFORE...WILL CONTINUE HIGH END LIKELY AND DEFINITE POPS FOR THE
WEST-NORTHWEST WIND LOCATIONS THURSDAY AFTERNOON/NIGHT. A
DISSIPATING HIGH PRESSURE RIDGE MOVING EAST INTO THE GREAT LAKES
REGION ON FRIDAY WILL LEAD TO BACKING WINDS AND SHIFT THE LAKE
EFFECT OFF SHORE FOR ALL BUT THE KEWEENAW PENINSULA.
MODELS DIFFER ON THE HANDLING OF THE NEXT NORTHERN STREAM WAVE AND
THE POTENTIAL DEVELOPMENT OF A LOW IN THE PLAINS MOVING THROUGH THE
LOWER GREAT LAKES FRIDAY NIGHT. 12Z ECMWF/GEM DETERMINISTIC RUNS IN
DECENT AGREEMENT WITH THE TRACK/STRENGTH OF THE LOW...BUT THE
12Z GFS FAILS TO SHOW A LOW. WAS HOPING THAT EACH MODELS
ENSEMBLE MEMBERS WOULD LEAD TO SOME SUPPORT IN EITHER
DIRECTION...BUT THEY ALL WERE AROUND 50/50 ON WHETHER A LOW WILL
OCCUR. THUS...WILL FOLLOW A MODEL CONSENSUS AND JUST SHOW
INCREASING CLOUDS AND SLIGHT CHANCES ALONG THE LAKE MICHIGAN
SHORELINE. BEHIND THE LOW...THERE WILL BE THE POTENTIAL FOR LIGHT
LAKE EFFECT IN THE WEST-NORTHWEST WIND BELTS THROUGH SUNDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1212 AM EST TUE JAN 28 2014
VERY COLD AIR WILL CONTINUE TO GENERATE LAKE EFFECT SNOW THROUGH
TODAY AT CMX...FAVORED BY WRLY WINDS. VSBY SHOULD REMAIN IN THE
VLIFR RANGE WITH OCNL PERIODS BELOW AIRFIELD MINIMUMS.
OTHERWISE...VFR CONDITIONS WILL PREVAIL AT IWD AND SAW INTO THE
AFTERNOON. ANOTHER WEAK DISTURBANCE MAY BRING SOME LIGHT SNOW AND
CIGS BACK TO NEAR MVFR DURING THE MID TO LATE AFTERNOON INTO THE
EVENING AT SAW/IWD.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 504 AM EST TUE JAN 28 2014
FREEZING SPRAY WILL CONTINUE TO BE A CONCERN THROUGH THE WEEK AS
ARCTIC AIR AND STRONG WINDS CONTINUE OFF AND ON. MAINLY W GALES TO
35KTS WILL BECOME MORE OUT OF THE SW THIS AFTERNOON...AND INCREASE TO
GALES OF 40KTS OVER E LAKE SUPERIOR FROM LATE THIS AFTERNOON THROUGH
TONIGHT AS WINDS SHIFT OUT OF THE W ONCE AGAIN. ANOTHER BRIEF PERIOD
OF S GALES TO 35KTS WILL BE POSSIBLE WEDNESDAY NIGHT OVER THE E.
HIGH PRESSURE OVER THE PLAINS STATES WILL SINK TO THE GULF COAST
THROUGH WEDNESDAY WHILE A LOW OVER HUDSON BAY SLOWLY WEAKENS. A LOW
OVER MANITOBA WEDNESDAY AFTERNOON WILL MOVE E TO JAMES BAY
THURSDAY AFTERNOON...SLIDING A TROUGH ACROSS THE GREAT LAKES.
ANOTHER HIGH PRESSURE SYSTEM WILL MOVE SE FROM ALBERTA INTO THE OHIO
VALLEY THURSDAY EVENING INTO FRIDAY...KEEPING A WEAK RIDGE OVER MUCH
OF THE AREA. MEANWHILE...A LOW OVER NE QUEBEC WILL BRING
SEVERAL TROUGHS OVER THE GREAT LAKES FRIDAY INTO SATURDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY UNTIL 6 AM EST WEDNESDAY FOR MIZ001-
003.
WIND CHILL WARNING UNTIL 1 PM EST /NOON CST/ THIS AFTERNOON FOR
MIZ001>005-009>014-084.
WIND CHILL ADVISORY FROM 1 PM EST /NOON CST/ THIS AFTERNOON TO
11 AM EST /10 AM CST/ WEDNESDAY FOR MIZ002-009-010.
WIND CHILL ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR MIZ006-007-
085.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST THURSDAY FOR LSZ267.
GALE WARNING UNTIL 7 AM EST WEDNESDAY FOR LSZ266-267.
HEAVY FREEZING SPRAY WARNING UNTIL 1 PM EST FRIDAY FOR LSZ266.
HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST /6 AM CST/ WEDNESDAY
FOR LSZ162.
HEAVY FREEZING SPRAY WARNING UNTIL 7 PM EST WEDNESDAY FOR LSZ263-
264.
GALE WARNING UNTIL 10 PM EST THIS EVENING FOR LSZ244-264.
GALE WARNING FROM 1 PM THIS AFTERNOON TO 1 AM EST WEDNESDAY FOR
LSZ263.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...VOSS
LONG TERM...SRF
AVIATION...JLB
MARINE...KF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1214 AM EST TUE JAN 28 2014
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 430 PM EST MON JAN 27 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A SHORTWAVE MOVED THROUGH
THE UPPER GREAT LAKES THIS AFTERNOON ON THE EDGE OF EXPANSIVE POLAR
VORTEX CENTERED ROUGHLY NEAR OR SOUTH OF JAMES BAY. CORE OF THE
COLDEST ARCTIC AIR MOVED THROUGH THE UPPER LAKES THIS AFTERNOON WITH
850 MB TEMPS NEAR -30C. WITH BEST FORCING ASSOC WITH THIS FEATURE
NOW EAST OF THE CWA...LES BANDS ON RADAR OVER ERN LAKE SUPERIOR HAVE
GENERALLY DECREASED IN INTENSITY AND BECOME MORE SPACED APART DUE TO
INFLUX OF DRIER AIR UPSTREAM.
WINDS CONTINUE TO GUSTS AT OR ABOVE 30 MPH OVER THE KEWEENAW AND THE
ERN SHORELINE PRODUCING OCCASIONAL WHITEOUT CONDITIONS IN SNOW AND
BLOWING SNOW. WIND CHILLS CONTINUE IN THE -23 TO -30F RANGE THIS
AFTERNOON. AS TEMPS CONTINUE TO FALL THIS EVENING...EXPECT WIND
CHILLS TO FALL TO THE -30F TO -35F RANGE.
WINDS WILL CONTINUE TO BACK WESTERLY BY LATE EVENING...FOCUSING LES
OVER THE KEWEENAW PENINSULA AND ALSO CLOSE TO THE ERN SHORE FROM
AROUND GRAND MARAIS EASTWARD. POTENTIAL FOR INCREASED LOW-LVL
CONVERGENCE INTO NW UPPER MI DUE TO LAND BREEZE ACTION COULD
ENHANCED LES TONIGHT OVER THE KEWEENAW PENINSULA. SO WILL CONTINUE
TO HIGHLIGHT HIGHER POPS/SLIGHTLY HIGHER ACCUMULATIONS ACROSS THE
KEWEENAW AND FAR ERN SHORELINE AREAS WHERE LES ADVISORIES WILL
CONTINUE INTO THIS EVENING EAST AND INTO TUE MORNING OVER THE
KEWEENAW. STILL...NOT REALLY EXPECTING MORE THAN 1-3 INCHES OF SNOW
DUE TO THE COLD COLUMN OF AIR IN PLACE AND LACK OF A DGZ.
HOWEVER...SNOW WILL CONTINUE TO BE EFFECTIVE IN REDUCING VSBY TO
NEAR ZERO AT TIMES WHERE LES IS OCCURRING.
WITH A FAIRLY TIGHT PRES GRADIENT EXPECTED ACROSS THE AREA
TONIGHT...LOW TEMPS WILL NOT BOTTOM OUT AS MUCH AS ONE WOULD EXPECT
GIVEN ARCTIC AIRMASS IN PLACE BECAUSE A STEADY WIND IS EXPECTED
THROUGH THE NIGHT. IF HIGH PRES WAS CENTERED MORE OVER THE AREA
INSTEAD OF OVER THE PLAINS...TEMPS WOULD PROBABLY PLUMMET TO -40F IN
THE TRADITIONAL COLD SPOTS...BUT THAT WON`T BE THE CASE TONIGHT.
OVERALL...EXPECT MINS GENERALLY IN THE -10F TO -20F RANGE OVER THE
FCST AREA...PERHAPS A FEW DEGREES WARMER OVER THE TIP OF THE
KEWEENAW AND FAR E ALONG LAKE SUPERIOR AND A FEW DEGREES COLDER
ALONG THE WRN INTERIOR ALONG THE WI BORDER. WITH THE WIND...WIND
CHILLS WILL FALL TO -30 TO -45F OVER MUCH OF AREA AND CONTINUE INTO
TUE MORNING. THIS WILL WARRANT CONTINUED WIND CHILL WARNING ACROSS
MOST OF THE AREA WITH WIND CHILL ADVISORIES FAR EAST CLOSER TO LAKE
SUPERIOR.
WINDS CONTINUING TO BACK WEST OR WSW SHOULD PUSH ANY REMAINING LES
OFFSHORE OF THE ERN SHORELINE AREAS BY EARLY TUE AND GRADUALLY PUSH
LES INTO MAINLY KEWEENAW COUNTY OVER THE NW BY TUE AFTERNOON. LOOK
FOR HIGHS GENERALLY ZERO TO 5 BELOW ACROSS MUCH OF THE CWA ON
TUESDAY UNDER CLEAR TO PARTLY CLOUDY SKIES.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 426 PM EST MON JAN 27 2014
A MUCH QUIETER PATTERN LOOKS TO BE IN STORE FOR THE END OF JANUARY
AND BEGINNING OF FEBRUARY. THE LARGE AND COLD UPPER TROUGH
CURRENTLY OVER THE REGION WILL SHIFT EAST ON TUESDAY NIGHT AND
WEDNESDAY ALLOWING WEAK RIDGING TO MOVE OVER THE AREA. THEN...THE
REST OF THE PERIOD WILL SEE A BROAD UPPER TROUGH OVER THE NORTHERN
HALF OF THE CONUS. THE COLDEST AIR WILL REMAIN IN CANADA...BUT
OCCASIONAL CLIPPER SYSTEMS WILL BRING BRIEF PERIODS OF SNOW AND
LAKE EFFECT ALONG WITH SLIGHTLY COOLER TEMPERATURES. OVERALL
THOUGH...TEMPERATURES THROUGH THE LONG TERM PERIOD WILL REMAIN
BELOW NORMAL WITH HIGHS MOST DAYS IN THE TEENS AND LOWS IN THE
SINGLE DIGITS BELOW ZERO.
LAKE EFFECT WILL BE ONGOING IN THE WEST TO SOUTHWEST SNOW BELTS TO
START TUESDAY EVENING...BUT A SURFACE TROUGH ASSOCIATED WITH A
SHORTWAVE MOVING THROUGH NORTHEAST ONTARIO WILL PUSH THROUGH ON
TUESDAY NIGHT. THIS TROUGH WILL BRING ADDITIONAL LOW LEVEL MOISTURE
TO THE AREA AND SHIFT WINDS A LITTLE MORE WESTERLY. BUT AS THIS
OCCURS...IT WILL PRODUCE A COUPLE DETRIMENTAL AFFECTS THROUGH THE
NIGHT INTO WEDNESDAY. ALTHOUGH 875MB TEMPERATURES WILL START OUT
AROUND -24C...THE WARMING ALOFT BEHIND THE FRONT UNDER WESTERLY
WINDS WILL END UP LOWERING INVERSION HEIGHTS THROUGH THE NIGHT.
THIS...COMBINED WITH THE HIGH PRESSURE RIDGE BRINGING DRIER AIR TO
THE REGION ON WEDNESDAY...WILL LEAD TO A QUICK DIMINISHMENT TO THE
LAKE EFFECT FROM WEST TO EAST TUESDAY NIGHT INTO WEDNESDAY MORNING.
IN RESPONSE TO THIS HIGH...A FAIRLY NICE BUT COOL DAY IS
EXPECTED ACROSS THE U.P. ON WEDNESDAY.
THE HIGH WILL QUICKLY SHIFT EAST WEDNESDAY AFTERNOON AND
EVENING...ALLOWING A COLD FRONT (ASSOCIATED WITH A CLIPPER MOVING
EAST THROUGH ONTARIO) TO SWEEP ACROSS THE U.P. WEDNESDAY NIGHT INTO
THURSDAY MORNING. MODELS VARY ON HOW FAR SOUTH THE BEST
FORCING/MOISTURE WILL SINK...SO WILL KEEP POPS AT CHANCE FOR NOW.
MUCH OF THE CLOUD/FORCING WITHIN THE DGZ...SO WOULD EXPECT SNOW
RATIOS TO BE WELL ABOVE CLIMO AND IN THE 20-30 TO 1 RANGE IF SNOW
OCCURS. AT THIS POINT...ONLY HAVE A LIGHT DUSTING TO AN INCH IN
THE FORECAST WITH THE HIGHEST AMOUNTS OVER THE EAST.
BEHIND THE FRONT...WESTERLY FLOW WILL SETUP AGAIN ACROSS THE U.P.
AS A 850MB TEMPS FALL TO AROUND -17C. THIS IS SUPPORTIVE FOR LAKE
EFFECT SNOW (ALONG WITH MUCH OF THE CLOUD BEING WITHIN THE DGZ) BUT
MODELS ARE INDICATING INVERSION HEIGHTS AROUND 5-6KFT.
THEREFORE...WILL CONTINUE HIGH END LIKELY AND DEFINITE POPS FOR THE
WEST-NORTHWEST WIND LOCATIONS THURSDAY AFTERNOON/NIGHT. A
DISSIPATING HIGH PRESSURE RIDGE MOVING EAST INTO THE GREAT LAKES
REGION ON FRIDAY WILL LEAD TO BACKING WINDS AND SHIFT THE LAKE
EFFECT OFF SHORE FOR ALL BUT THE KEWEENAW PENINSULA.
MODELS DIFFER ON THE HANDLING OF THE NEXT NORTHERN STREAM WAVE AND
THE POTENTIAL DEVELOPMENT OF A LOW IN THE PLAINS MOVING THROUGH THE
LOWER GREAT LAKES FRIDAY NIGHT. 12Z ECMWF/GEM DETERMINISTIC RUNS IN
DECENT AGREEMENT WITH THE TRACK/STRENGTH OF THE LOW...BUT THE
12Z GFS FAILS TO SHOW A LOW. WAS HOPING THAT EACH MODELS
ENSEMBLE MEMBERS WOULD LEAD TO SOME SUPPORT IN EITHER
DIRECTION...BUT THEY ALL WERE AROUND 50/50 ON WHETHER A LOW WILL
OCCUR. THUS...WILL FOLLOW A MODEL CONSENSUS AND JUST SHOW
INCREASING CLOUDS AND SLIGHT CHANCES ALONG THE LAKE MICHIGAN
SHORELINE. BEHIND THE LOW...THERE WILL BE THE POTENTIAL FOR LIGHT
LAKE EFFECT IN THE WEST-NORTHWEST WIND BELTS THROUGH SUNDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1212 AM EST TUE JAN 28 2014
VERY COLD AIR WILL CONTINUE TO GENERATE LAKE EFFECT SNOW THROUGH
TODAY AT CMX...FAVORED BY WRLY WINDS. VSBY SHOULD REMAIN IN THE
VLIFR RANGE WITH OCNL PERIODS BELOW AIRFIELD MINIMUMS.
OTHERWISE...VFR CONDITIONS WILL PREVAIL AT IWD AND SAW INTO THE
AFTERNOON. ANOTHER WEAK DISTURBANCE MAY BRING SOME LIGHT SNOW AND
CIGS BACK TO NEAR MVFR DURING THE MID TO LATE AFTERNOON INTO THE
EVENING AT SAW/IWD.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 430 PM EST MON JAN 27 2014
FREEZING SPRAY WILL CONTINUE TO BE A PROBLEM THROUGH AT LEAST
WED MORNING AS ARCTIC AIR AND STRONG WINDS REMAIN. NW GALES TO
40 KTS WILL SHIFT WESTERLY TO 35 KNOTS THIS EVENING AND CONTINUE
THROUGH TUESDAY NIGHT OVER ERN LAKE SUPERIOR. ANOTHER SURGE OF
ARCTIC AIR WILL LIKELY RESULT IN A BRIEF PERIOD OF SW GALES TO 35 KT
WED NIGHT WITH MORE HEAVY FREEZING SPRAY THU INTO FRI MORNING.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WIND CHILL WARNING UNTIL 1 PM EST /NOON CST/ THIS AFTERNOON FOR
MIZ001>005-009>014-084.
WIND CHILL ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR MIZ006-007-
085.
LAKE EFFECT SNOW ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
MIZ001-003.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST FRIDAY FOR LSZ266-
267.
GALE WARNING UNTIL 7 AM EST WEDNESDAY FOR LSZ249>251-266-267.
GALE WARNING UNTIL 10 PM EST THIS EVENING FOR LSZ244-245-248-264-
265.
HEAVY FREEZING SPRAY WARNING UNTIL 7 PM EST THURSDAY FOR LSZ263-
264.
HEAVY FREEZING SPRAY WARNING UNTIL 1 AM EST /MIDNIGHT CST/
THURSDAY FOR LSZ162.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...VOSS
LONG TERM...SRF
AVIATION...JLB
MARINE...VOSS
AREA FORECAST DISCUSSION...UPDATED
NWS TWIN CITIES/CHANHASSEN MN
836 PM CST WED JAN 29 2014
.UPDATE...
ISSUED AT 836 PM CST WED JAN 29 2014
SIGNIFICANT UPDATES HAVE BEEN MADE TO THE FORECAST LATE TONIGHT
AND EARLY THURSDAY. SHORT TERM MODELS AND THE 00Z NAM HAVE COME
CONSIDERABLY FARTHER NORTH AND HAVE BECOME MORE INTENSE WITH THE
BAND OF SNOW. IT WILL BE A QUICK HITTING SYSTEM...BUT IT WILL BE
ACCOMPANIED BY VERY HEAVY SNOW DURING THE MORNING RUSH WHICH WILL
LIKELY BRING SEVERE IMPACTS.
THE LOW CURRENTLY IS LOCATED OVER SOUTHWESTERN SD AND WILL TRACK
ALONG THE SD/NE BORDER INTO SOUTHEASTERN MN BY MIDDAY THURSDAY.
THE SNOW IS CURRENTLY FALLING IN A RELATIVELY DATA SPARSE AREA OF
SOUTHEASTERN MT...BUT MILES CITY HAS REPORTED 1/2-3/4 MILE SNOW
FOR THE PAST FEW HOURS. AS THIS DISTURBANCE ROTATES EASTWARD...THE
700 MB TROUGH WILL DEEPEN OVER MN AT 12Z AND CONTINUE TO DO SO
OVER WI BY 18Z. DEEP OMEGA WITHIN THE DGZ AND A FAIRLY HIGH AMOUNT
OF MOISTURE FOR LATE JANUARY WITH PW VALUES OF AROUND 0.4 INCHES
/ABOVE THE 75TH PERCENTILE/...SHOULD WORK TO PRODUCE VERY INTENSE
SNOW RATES AT TIMES. THESE SNOW RATES COULD REACH 1-2 INCHES PER
HOUR DURING THE HEIGHT OF THE EVENT...SURE TO WREAK HAVOC WITH THE
MORNING COMMUTE. THE HOPWRF...HRRR...AND RAP ALL GENERALLY AGREE
WITH THE LOCATION/AXIS OF HEAVY SNOW STRETCHING FROM GLENCOE TO
THE TWIN CITIES AND RICE LAKE. NEW 00Z NAM HAS COME INTO LINE WITH
THIS IDEA AS WELL SO CONFIDENCE HAS INCREASED ENOUGH TO POST A
WARNING ALONG THIS AXIS AND AN ADVISORY ELSEWHERE. FUTURE
ADJUSTMENTS MAY BE NECESSARY AS THE REST OF THE 00Z MODEL SUITE
IS GENERATED.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 249 PM CST WED JAN 29 2014
ACCUMULATING SNOW EXPECTED TO BEGIN OVERNIGHT ACROSS THE
SOUTHWESTERN MINNESOTA AND MOVE WEST TO EAST ACROSS THE REMAINDER OF
SOUTHERN MINNESOTA AND WESTERN WISCONSIN DURING THE MORNING
TOMORROW. THE MORNING COMMUTE WILL BE HEAVILY IMPACTED...AS THE
HEAVIEST SNOW LOOKS TO REACH THE METRO FROM ROUGHLY 6AM-9AM. A
WINTER WEATHER ADVISORY WAS POSTED AFTER COLLABORATION WITH ARX AND
DMX...WITH THE HEAVIEST SNOW AMOUNTS EXPECTED IN IN THE ARX CWA.
STILL...ALBERT LEA THROUGH RED WIND...AND OVER TO EAU CLAIRE ARE
EXPECTED TO SEE ROUGHLY 3-4 INCHES OF SNOW...WHICH WILL BE HEAVY AT
TIMES DURING THE PEAK TRAVEL TIME THURSDAY MORNING. THE 29.12 RUN
OF THE ECMWF INCREASED QPF TO THE NORTH AND BETTER MATCHES THE NCEP
MODELS. PREVIOUS FORECAST LOOKED VERY GOOD...SO ONLY MINOR TWEAKS
WERE MADE...MAINLY TO THE TIMING WHICH DELAYED THE ONSET OF THE SNOW
BY ABOUT TWO HOURS. UPPER LEVEL DYNAMICS LOOK GOOD TOMORROW MORNING
ACROSS THE AREA...WITH THE BEST UPPER LEVEL FORCING MOVING ACROSS
SOUTHERN MN OVERNIGHT AND INCREASING OVER SOUTHEASTERN MN INTO
WESTERN WI. THE GOING FORECAST CALLS FOR THE HIGHEST AMOUNTS IN
THIS AREA...PRIMARILY FALLING FROM 12Z TO 18Z TOMORROW. THE LIFT
STILL LOOKS GOOD ON THE 295K SURFACE AS THE STRONG UPGLIDE BEGINS TO
COINCIDE WITH A SATURATED ENVIRONMENT BY 09Z ACROSS WESTERN MN. FOR
THE METRO...2"-3" STILL LOOKS ON TRACK ACROSS THE SOUTHERN PORTION...WITH
CLOSER TO 1"-2" ACROSS THE NORTH. WINDS WILL TURN NORTHWEST AND
GET BLUSTERY TOMORROW AFTERNOON AS THE SNOW MACHINE SHUTS OFF.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 249 PM CST WED JAN 29 2014
LONGER TERM TRENDS CHANGE LITTLE AS FAR AS THE UPPER LEVEL FLOW
PATTERN ACROSS THE NORTHERN TIER STATES. WE REMAIN LOCKED IN THE
COLDER THAN NORMAL REGIME THROUGH THIS FORECAST PERIOD. SEVERAL
ARCTIC COLD FRONTS SWEEP ACROSS THE REGION. THE FIRST EXITS THE
AREA THURSDAY NIGHT. THIS MAY GENERATE WIND CHILL ADVISORY
CRITERIA OVER MUCH OF THE REGION SPREADING FROM WEST TO EAST BY
FRIDAY MORNING.
THEN ON SATURDAY....THE FRONT MOVES THROUGH AND THIS WILL BRING A
SMALL CHANCE OF LIGHT SNOW TO THE SOUTH AND EAST PORTION OF THE
AREA. MOISTURE WILL BE LACKING WITH THE SYSTEM...BUT MAY STILL
MUSTER ENOUGH TO GENERATE SOME LIGHT SNOW. MOST DETERMINISTIC
MODELS CONTINUE TO SHOW SOME LIGHTER QPF IN EASTERN AREA...WITH
THE GFS ENSEMBLES SHOWING TH MAIN FOCUS MORE TO THE FAR SOUTHERN
MN DURING THE PERIOD.
COLDER AIR FOLLOWS THIS SYSTEM...BUT NOT AS COLD AS PREVIOUS
SYSTEMS. USED BIAS CORRECTED TEMPERATURES FOR NOW...AS WE HAVE BEEN
RUNNING A BIT COLD OF LATE IN VERIFICATION WITH THESE COLD AIR
INTRUSIONS. VERY LITTLE SNOW COVER TO THE SOUTH AND WEST OF
MINNESOTA...SO THERE IS OPPORTUNITY TO WARM A BIT MORE SIGNIFICANTLY
AHEAD OF EAST OF THE FRONTS. WILL CONTINUE THIS TREND FOR NEXT
MONDAY AS WELL...WITH PERHAPS A MORE SIGNIFICANT COLD AIR SURGE
COMING TOWARD MIDWEEK NEXT WEEK.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 532 PM CST WED JAN 29 2014
MODELS HAVE SHIFTED THE REGION OF HEAVIEST SNOW NORTHWARD QUITE A
BIT WITH THE LATE AFTERNOON RUNS...AND MOST OF THE SHORT TERM
RELIABLE ONES ARE SHOWING HIGH IMPACT SNOWS THURSDAY MORNING. THE
SNOW WILL ARRIVE BETWEEN 09-12Z AND QUICKLY BECOME MODERATE OR
HEAVY DURING THE MORNING COMMUTE FOR ALL OF THE TAF SITES. LIFR
CONDS EXPECTED FOR A PERIOD OF 3-4 HOURS UNTIL IMPROVING
CONDITIONS BY LATE MORNING. TOTAL ACCUMS OF 3-6 INCHES APPEAR
LIKELY WITH HOURLY RATES AS HIGH AS 1-2 INCHES POSSIBLE. UNTIL THE
SNOW ARRIVES...VFR CONDITIONS EXPECTED.
KMSP...THE SNOW WILL ARRIVE SOMETIME AROUND 11Z LATE TONIGHT AND
QUICKLY BECOME HEAVY SHORTLY THEREAFTER UNTIL ABOUT 15Z.
CONFIDENCE IS MODERATE-HIGH THAT A FEW INCHES WILL FALL ON THE
TERMINAL DURING THIS TIME AND VERY HIGH SNOW WILL FALL DURING THE
MORNING COMMUTE.
/OUTLOOK FOR KMSP/
THU NIGHT...VFR. WINDS NW AT 10-15KTS.
FRI...VFR. WINDS WSW 5 KTS.
SAT...VFR. WINDS SW 5KTS EARLY BCMG NW AT 10G15KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...WINTER WEATHER ADVISORY FROM 5 AM TO NOON CST THURSDAY FOR
MNZ044-045-067-074>078-082>085-091>093.
WINTER WEATHER ADVISORY FROM 2 AM TO NOON CST THURSDAY FOR
MNZ041>043-047>050-054>058-064-065-073.
WINTER STORM WARNING FROM 5 AM TO NOON CST THURSDAY FOR
MNZ051>053-059>063-066-068>070.
WI...WINTER WEATHER ADVISORY FROM 5 AM TO NOON CST THURSDAY FOR
WIZ026-028.
WINTER STORM WARNING FROM 5 AM TO NOON CST THURSDAY FOR
WIZ014>016-023>025-027.
&&
$$
UPDATE...BORGHOFF
SHORT TERM...SPD
LONG TERM...DWE
AVIATION...BORGHOFF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON MS
905 AM CST TUE JAN 28 2014
.MESOSCALE UPDATE...
DUAL POL RADAR DATA AND SURFACE OBSERVATIONS NICELY DEPICT TRANSITION
LINE BETWEEN SLEET/SOME FREEZING RAIN AND AREA THAT IS PRIMARILY SNOW
WITH SOME SLEET MIXED IN. THAT LINE CURRENTLY LOOKS TO BE RUNNING
FROM BUDE TO MAGEE TO MERIDIAN. SATELLITE AND RADAR DATA SHOW
LARGEST...MAIN WAVE OF LIFT IS NOW IMPINGING ON THE WESTERN SIDE OF
OUR SERVICE AREA. THIS WILL LIKELY PIVOT THE STEADIER SNOW A BIT
FARTHER NORTH INTO CENTRAL AND EASTERN MISSISSIPPI BEFORE BACK EDGE
BEGINS TO PULL INCREASINGLY RAPIDLY TO THE EAST. STILL THINKING AREAS
UP ALONG HIGHWAY 82 WILL SEE NOTHING MORE THAN FLURRIES WITH A
DUSTING IN A FEW SPOTS.
IN THE NEAR TERM...THIS IS GOING TO PUSH STEADIER SNOW BACK ACROSS
THE JACKSON METRO AREA FOR A COUPLE OF HOURS BEFORE IT STARTS TO PULL
AWAY TO THE EAST...WHILE MERIDIAN WILL SEE A LONGER PERIOD OF
STEADIER SNOW MIXED WITH SLEET EARLY ON. FARTHER TO THE SOUTH...12Z HRRR
IMPLIES THAT PRECIPITATION WILL PERSIST INTO AT LEAST EARLY AFTERNOON
BEFORE BEGINNING TO GRADUALLY END FROM THE WEST. PRECIPITATION WILL
BE TRANSITIONING TO ALL SNOW AS WELL FROM THE WEST-NORTHWEST...BUT
LATEST RUC SOUNDINGS IMPLY THIS TRANSITION WILL BE SLOWER AS ONE GOES
TO THE SOUTHEAST...AND OVER AREAS SOUTH OF HIGHWAY 98 MUCH OF PRECIP
EVENT MAY END UP BEING PRIMARILY SLEET AND FREEZING RAIN. RIGHT NOW
CURRENT ACCUMULATIONS AND WARNING/ADVISORIES SEEM OK...BUT WILL BE
MONITORING CLOSELY FOR POTENTIAL FOR LOCALLY HEAVIER ACCUMULATIONS
OF SNOW AND/OR ICE BASED ON LATEST TRENDS. RIGHT NOW...BEST GUESS ON
POTENTIAL "HOT SPOTS" FOR HEAVIER SNOW WOULD BE ALONG AN AXIS FROM
HARRISONBURG LA TO MENDENHALL TO QUITMAN...WHILE ICE WOULD OF COURSE
BE IN SOUTHEAST MS.
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 31 16 37 17 / 76 8 0 7
MERIDIAN 28 15 35 13 / 80 13 0 9
VICKSBURG 32 15 39 18 / 54 6 0 7
HATTIESBURG 31 17 36 16 / 95 21 0 7
NATCHEZ 31 15 40 19 / 82 8 0 8
GREENVILLE 29 14 38 18 / 20 4 0 5
GREENWOOD 29 11 36 16 / 23 4 0 6
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...HARD FREEZE WARNING UNTIL NOON CST WEDNESDAY FOR MSZ018-019-
025>039.
WIND CHILL ADVISORY UNTIL NOON CST TODAY FOR MSZ018-019-025>039.
WINTER STORM WARNING UNTIL 6 PM CST THIS EVENING FOR MSZ054>066-
072>074.
WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR
MSZ043>053.
LA...WINTER STORM WARNING UNTIL 6 PM CST THIS EVENING FOR LAZ024-026.
WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR LAZ016-
023-025.
AR...HARD FREEZE WARNING UNTIL NOON CST WEDNESDAY FOR ARZ074-075.
WIND CHILL ADVISORY UNTIL NOON CST TODAY FOR ARZ074-075.
&&
$$
AEG
AREA FORECAST DISCUSSION
NWS GLASGOW MT
807 PM MST WED JAN 29 2014
.SHORT TERM...FOR NORTHEAST MONTANA...TONIGHT THROUGH FRIDAY...
EVENING UPDATE...
SNOW SHOWERS CONTINUE ACROSS THE AREA BUT A LIGHTENING TREND IS
PRESENTING ITSELF ACROSS RADAR TRENDS FROM THE NORTHWEST MOVING
SOUTHEAST. RUC AND HRRR QPF TRENDS ALSO SHOW DIMINISHING TRENDS
RAPIDLY AFTER MIDNIGHT. BULK OF THE SNOWFALL THUS FAR WAS A LITTLE
FARTHER NORTH THAN ANTICIPATED AND NUDGED HIGHER POPS NORTH OF
THEIR CURRENT PLACEMENT TO REFLECT THIS. GAH
PREVIOUS LONG TERM DISCUSSION...
A CLIPPER MOVING ACROSS THE PRAIRIE PROVINCES HAS SENT A COLD
FRONT SOUTH THROUGH NORTHEAST MONTANA TODAY...NUDGING
TEMPERATURES COLDER. AN ENERGETIC SHORTWAVE TROUGH MOVING INTO THE
PACIFIC NORTHWEST HAS SENT MOISTURE OVER THE DIVIDE THAT HAS
INITIATED A ROUND OF ACCUMULATING SNOW FOR WESTERN AND CENTRAL
MONTANA THIS MORNING...THAT WILL EXPAND TO SOUTHERN PORTIONS OF
NORTHEAST MONTANA LATE THIS AFTERNOON...CONTINUING INTO THURSDAY
BEFORE ENDING. A WINTER WX ADVISORY REMAINS IN EFFECT THROUGH
THURSDAY. BOTH THE GFS AND NAM SUGGEST QPF AMOUNTS OF AROUND 0.15
TO 0.20 INCH FOR PRAIRIE COUNTY THIS EVENING. THEREFORE WILL ADD
THE COUNTY TO THE SNOW ADVISORY. OVERALL THE ORIGINAL ADVISORY
STILL LOOKS GOOD...WITH 2 TO 6 INCHES EXPECTED IN THE HEADLINED
AREAS.
THE COLD FRONT WILL CONTINUE SOUTH OF THE REGION AS COLD AIR
ADVECTS IN FROM THE NORTH. 850MB TEMPERATURE AT 00Z THURSDAY
WILL FALL TO AROUND -10C. 24 HOURS LATER EXPECT -20C. SO HIGHS ON
THURSDAY WILL RUN AROUND 15F DEGREES COLDER THAN WEDNESDAY.
SURFACE HIGH PRESSURE SETTLING INTO THE AREA WILL DIMINISH
WIND...WHICH WILL ALSO MINIMIZE THE WIND CHILL PROBLEMS. AREAS IN
THE NORTHEAST LATE TONIGHT HOWEVER MAY HAVE ENOUGH WIND TO
APPROACH -20 BELOW WIND CHILLS...WHICH WILL BE MENTIONED IN THE
HWO.
THURSDAY NIGHT AND FRIDAY...CLEARING SKIES WILL PRODUCE TO COLDEST
NIGHT WITH LOWS IN THE TEENS BELOW ZERO. AGAIN WIND WILL MOSTLY
BE LIGHT...BUT A FEW AREAS OF HAZARDOUS WIND CHILLS ARE POSSIBLE.
ANOTHER BACKDOOR COLD FRONT FRIDAY WILL INCREASE SKY COVER...
LIMITING ANY WARMING TO THE AREA. HIGHS WILL CONTINUE COLDER THAN
NORMAL.
.LONG TERM...FRIDAY NIGHT THROUGH WEDNESDAY...
VARIOUS MODEL ENSEMBLES ALL TEND TO SHOW THE PATTERN OF A COLD
TROUGH TO THE EAST WITH A WARM RIDGE TO THE WEST CONTINUING FOR THE
NEXT WEEK. THE PACIFIC RIDGE LOOKS TO MIGRATE A LITTLE FURTHER
WEST...PUTTING THE NORTHEAST MONTANA AREA ON THE WEST SIDE OF THE
COLD AIR TO THE EAST. THE COLD AIR THAT MOVES INTO THE REGION
TODAY WILL PERSISTS THROUGH THE LONG TERM WITH OCCASIONAL MINOR
COLD FRONTS REINFORCING IT...AS THE EASTERN TROUGH TAKES A
BROADENING AND DEEPENING AND PERSISTENT TURN.
BOTH THE EC AND GFS MODELS HAVE THE AREA IN
A COLD AND DRY REGIME FOR SATURDAY THROUGH WEDNESDAY WITH LOWS AND
HIGHS IN THE SINGLES DIGITS BELOW AND ABOVE...RESPECTIVELY. AREAS
THAT RECEIVE SIGNIFICANT SNOW FALL TODAY...EXPECTED TO BE THE
SOUTHWEST HALF OF THE CWA...COULD HAVE TEMPERATURES BELOW THOSE
CURRENTLY ANTICIPATED DUE TO RADIATION FROM NEW SNOW AT NIGHT.
A REINFORCING FRONT SEEN IN THE GFS AND EC MODELS SOMETIME AROUND
TUESDAY PROVIDES THE MAIN CHANCE OF SNOW IN THE EXTENDED. MODELS
ARE VERY DRY WITH THIS FROPA...BUT THERE IS SOME CHANCE OF LIGHT
SNOW. MARTIN
PREVIOUS LONG TERM DISCUSSION...
SYNOPTIC SET UP... LONG TERM BEGINS WITH A LARGE COLD CORE TROUGH
STRETCHING FROM QUEBEC... THROUGH ONTARIO AND SOUTHERN MANITOBA...
AND INTO NORTHEAST MONTANA. FLOW THEN TURNS NORTH TO NORTHWEST
THROUGH MUCH OF THE US AND CANADIAN ROCKY MOUNTAINS. A LARGE RIDGE
SETS OFF THE WEST COAST OF THE CONUS AND CANADA AS WELL...
TERMINATING OVER SOUTHERN ALASKA.
THROUGH MUCH OF THE LONG RANGE. THE RIDGE OFF THE NORTH AMERICAN
COAST WILL STAY IN PLACE REFUSING TO STEP ON SHORE. THIS HAS
ALLOWED THE HUDSON BAY LOW A MUCH WIDER BERTH TO FREELY FLOAT
AROUND THE EASTERN US AND CANADA AND TO BE ABLE TO MAKE ITS WAY
OVER WEST TO THE FRONT RANGE WITHOUT ANY RESISTANCE. THIS WILL
KEEP NORTHEAST MONTANA SEASONALLY COLD THROUGH THE MAJORITY OF THE
LONG RANGE. THE DRY CONTINENTAL AIR WILL ALSO KEEP MOST OF THE
PERIODS DRY AND FREE FROM SNOW SHOWERS. THE ONE EXCEPTION TO THIS
WILL BE SUNDAY NIGHT/MONDAY WHEN A SHORTWAVE EMBEDDED IN THE
NORTHWEST TO NORTHERN FLOW WILL BE ABLE TO MAKE ITS WAY FAR ENOUGH
EAST TO GENERATE A FEW SNOW SHOWERS ACROSS OUR WESTERN MOST ZONES.
GAH
&&
.AVIATION...
IFR/MVFR. IFR VISIBILITIES ARE EXPECTED TO BECOME MVFR TONIGHT.
MVFR CEILINGS WILL LINGER INTO THURSDAY MORNING.
NORTH WINDS ARE EXPECTED TO BE LIGHT WITH SPEEDS AROUND 10 KTS OR
LESS INTO THURSDAY MORNING.
VFR CONDITIONS ARE EXPECTED TO RETURN THURSDAY AFTERNOON OR
EVENING. TFJ
&&
.GLASGOW WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 5 PM MST THURSDAY FOR CENTRAL AND
SOUTHEAST PHILLIPS...GARFIELD...PETROLEUM...PRAIRIE...SOUTHWEST
PHILLIPS.
&&
$$
WEATHER.GOV/GLASGOW
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
856 PM CST WED JAN 29 2014
.UPDATE...
ISSUED AT 840 PM CST WED JAN 29 2014
00Z UPPER AIR ANALYSIS INDICATED A POTENT WAVE ENTERING THE
PACIFIC NORTHWEST...WITH A 160 KNOT JET AT 300 MB AND 150M HEIGHT
FALLS AT 500. SURFACE LOW PRESSURE ACROSS THE SD/NE/WY BORDER
REGION WILL CONTINUE TO MOVE ALMOST DUE EAST TONIGHT AS THIS WAVE
CONTINUES TO CROSS THE ROCKIES. NEW 00Z NAM AND LATEST SEVERAL
ROUNDS OF THE RAP ALL SUGGEST THAT THE BULK OF THE PRECIP WILL
REMAIN ACROSS SOUTH DAKOTA...WITH JUST A GLANCING BLOW ALONG THE
NE/SD BORDER THROUGH THE NIGHT. INITIALLY...IT WILL PROBABLY JUST
BE RAIN AS TEMPS AHEAD OF THE LOW REMAIN QUITE MILD IN THE UPPER
30S. STILL COULD BE MIXED WINTRY PRECIPITATION...BUT ALSO AM
THINKING PRECIP MAY EVEN MOVE OUT BEFORE THE COLDER AIR MOVES IN.
EITHER WAY...IT`S NOT A VERY BIG SYSTEM FOR OUR AREA WITH FAIRLY
LOW POPS EXPECTED. MODELS DO SUGGEST THAT THE TRAILING END OF THE
COLD FRONT COULD SEE SOME MOISTURE INCREASE BY MID TO LATE
MORNING...SO WOULD NOT BE SURPRISED TO SEE SOME SPOTTY PRECIP
DEVELOP IN SOUTHEAST NEBRASKA THURSDAY MORNING...BUT PUSHING
SOUTHEAST OF THE AREA BY NOON.
&&
.SHORT TERM...(TONIGHT THROUGH SATURDAY)
ISSUED AT 307 PM CST WED JAN 29 2014
EARLY AFTERNOON WATER VAPOR IMAGERY INDICATED A SHORTWAVE TROUGH
MOVING THROUGH WA. THIS SYSTEM WAS ASSOCIATED WITH A 120 KT H25
JET AND 130 M H5 HEIGHT FALLS. THIS SYSTEM WILL MOVE INTO THE
NORTHERN PLAINS TONIGHT AND ALLOW FOR A COLD FRONT TO SWEEP
THROUGH THE FA ON TUESDAY. AHEAD OF THE SYSTEM WE SHOULD CONTINUE
TO SEE A WARM AND BREEZY EVENING AS LOW PRESSURE CONTINUES TO
DEEPEN OVER THE HIGH PLAINS. THIS LOW WILL TAKE A TRACK ALONG THE
SD/NEB BORDER OVERNIGHT AND INTO NORTHERN IA ON THU. AS PREVIOUSLY
NOTED MUCH OF THE LARGE-SCALE FORCING FOR ASCENT WILL GO NORTH OF
OUR FA OVER SD/MN ASSOCIATED WITH THIS SYSTEM. LOW TO MID LEVEL
FRONTOGENESIS WILL INCREASE AS THE LOW MOVES BY TONIGHT AND THIS
MAY STILL BE ENOUGH LIFT TO PRODUCE SOME LIGHT PRECIP OVER OUR
EXTREME NORTH...GENERALLY NORTH OF A LINE FROM AROUND NLG TO TQE
TO HNR. POINT FORECAST SOUNDINGS STILL INDICATE THAT A MIX OF
LIGHT PRECIP WILL BE POSSIBLE IF ANYTHING FALLS. WE ARE NOT
EXPECTING ANY ICE ACCUMULATION ANY ANY SNOWFALL WOULD BE A TENTH
OF AN INCH OF LESS.
A BREAK IN WEATHER SYSTEMS IS EXPECTED FOR MOST OF THURSDAY AS THE
LEAD SHORTWAVE TROUGH MOVES EAST AND THE NEXT SHORTWAVE ISN`T
EXPECTED UNTIL THURSDAY NIGHT. THIS SHORTWAVE TROUGH IS EXPECTED
TO MOVE ACROSS NEB/IA OVERNIGHT THU AND ACT ON THE PRE-EXISTING
THERMAL GRADIENT TO PRODUCE ENOUGH FRONTAL CIRCULATION FOR LIGHT
PRECIP. THE THERMAL PROFILE WOULD SUPPORT ALL SNOW BY THIS TIME.
ANY PRECIPITATION ASSOCIATED WITH THE THURSDAY NIGHT WAVE SHOULD
DISSIPATE BY FRI AFTERNOON AS THE CIRCULATION ENDS. AMOUNTS WILL
GENERALLY BE LIGHT AND MAINLY OVER THE SOUTHWEST 2/3RD OF THE
FA...BUT AMOUNTS AROUND AN INCH ARE NOT OUT OF THE QUESTION.
ANOTHER LITTLE BREAK IS EXPECTED IN THE LIFT IS EXPECTED FRI
AFTERNOON BEFORE A BIT STRONGER SHORTWAVE TROUGH IS EXPECTED FOR
FRIDAY NIGHT. THIS WILL CREATE A BIT STRONGER FRONTOGENESIS...HAVE
BETTER MOISTURE TO WORK WITH...AND STATIC STABILITY APPEARS
WEAKER. THUS A STRONGER FRONTAL CIRCULATION IS LIKELY TO DEVELOP
FRI NIGHT...ESPECIALLY IN THE SOUTHERN FA AND 1-2 INCHES APPEAR
POSSIBLE AT THIS TIME. THE NORTHEASTERN THIRD OF THE FA WILL
STRUGGLE THROUGH BOTH EVENTS TO ACCUMULATE SNOW DUE TO LOW LEVEL
DRY AIR BEING ADVECTED IN FROM THE NORTHEAST AND WILL HAVE THE
LOWEST SNOW TOTALS NORTHEAST OF A LINE FROM NORFOLK TO OMAHA TO
RED OAK. WE DID LINGER SOME POPS INTO SAT MORNING BEFORE THIS
SYSTEM EXITS TO THE EAST.
.LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 307 PM CST WED JAN 29 2014
AN UPPER LEVEL TROUGH WILL BE MOVING ACROSS THE SOUTHWESTERN
CONUS ALLOWING SOUTHWESTERLY FLOW OVER THE NATIONS MID SECTION AT
THE BEGINNING OF THE FORECAST PERIOD. THE BEGINNING OF THE PERIOD
WILL BE COOL AND DRY. THE NEXT CHANCE FOR SNOW WILL BE MONDAY
NIGHT INTO TUESDAY OVER THE SOUTHERN THIRD OF THE FORECAST AREA IN
ADVANCE OF A PIECE OF SHORTWAVE ENERGY MOVING NORTHEAST FROM THE
CENTRAL PLAINS. TEMPERATURES OVER THE TIME PERIOD LOOK TO BE
SLIGHTLY BELOW NORMAL WITH HIGHS IN THE TEENS AND 20S AND LOWS IN
THE SINGLE DIGITS TO MID TEENS.
&&
.AVIATION...(00Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 524 PM CST WED JAN 29 2014
MAIN FORECAST PROBLEM THROUGH THE PERIOD WILL BE WINDS. SOUTH TO
SOUTHWEST WINDS AROUND 15 KNOTS WILL PREVAIL EARLY AHEAD OF A
COLD FRONT THAT IS EXPECTED TO ARRIVE AROUND 12Z AT KOFK AND
14/15Z AT KLNK/KOMA. COULD ALSO SEEM SOME NON CONVECTIVE LOW LEVEL
WIND SHEAR AT ALL THREE TAF SITES WITH WIND SPEEDS UP AT 2000 FEET
INCREASING FROM AROUND 45 KNOTS TO AROUND 60 KNOTS BY 03-07Z...
THAT WILL BE PRESENT UNTIL THE FRONT ARRIVES LATER ON.
SHOULD SEE VFR CLOUDS MOST OF THE PERIOD...ALTHOUGH COULD SEE MVFR
CLOUDS FOR A COUPLE OF HOURS AS THE FRONT MOVES THROUGH...ESPECIALLY
AT KOFK AND POSSIBLY AT KOMA.
THERE WILL ALSO BE SMALL CHANCES OF MIXED WINTRY PRECIPITATION
JUST NORTH OF KOFK 08-12Z...AND JUST NORTH OF KOMA AT 11-14Z...BUT
DID NOT HAVE CONFIDENCE TO INCLUDE IN THE TAF FORECAST AT THIS
TIME.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
UPDATE...DEWALD
SHORT TERM...BOUSTEAD
LONG TERM...KERN
AVIATION...DEWALD
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1200 PM CST TUE JAN 28 2014
.UPDATE...
ISSUED AT 536 AM CST TUE JAN 28 2014
NO SUBSTANTIVE CHANGES NEEDED FOR THIS ESTF UPDATE. HOURLY TEMP/
DWPT/WIND WERE REFRESHED WITH CONSENSUS OF SHORT-TERM GUIDANCE.
FCST DWPTS ARE RUNNING A LITTLE ABOVE REALITY...BUT THIS HAS BEEN
CORRECTED.
THE SFC LOW IS NOW OVER HARLAN COUNTY AND HEADING ESE. SKIES HAVE
LARGELY CLEARED IN ITS WAKE. THE ONLY CLOUDS WE/VE NOTED ARE AT
BBW. THE SUN WILL HAVE TO MAKE IT OVER THE BATCH OF CLOUDS
ASSOCIATED WITH THE LOW. BEYOND THAT...LOOKS LIKE A NICE DAY WITH
THE EXTREME COLD OF YESTERDAY EASING A BIT.
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 341 AM CST TUE JAN 28 2014
...A NEW AND COLDER PATTERN IS NOW ESTABLISHED WITH THE COLD
BEGINNING TO EASE TODAY AND A NICE JUMP TOMORROW BUT THEN IT/S
BACK TO MORE COLD...
ALOFT: A TROF WAS MOVING THRU THE CNTRL PLAINS EARLY THIS
MORNING. IT WILL DEPART TO THE E TODAY WITH NNW FLOW GRADUALLY
BECOMING ANTICYCLONIC TONIGHT. HEIGHTS WILL RISE ABOUT 50M TODAY
AND ROUGHLY 100M TONIGHT.
SURFACE: EXPANSIVE HIGH PRES STRETCHED FROM MT-NE-IL. THIS HIGH
WAS SLOWLY SINKING S AND WILL SETTLE OVER TX AND THE GULF COAST
TONIGHT.
OVERALL...QUIET WX THRU TONIGHT.
NOW THRU SUNRISE: VARIABLE CLOUDS. SURFACE OBS SHOW A WEAK LOW
BETWEEN LBF-IML-MCK-LXN. MULTIPLE HI-RES MODELS DEVELOP A BURST
OF LIGHT SNOW /-SN/ OVER N-CNTRL KS AS THIS LOW DEPARTS WITH THE
UPPER TROF. THIS HAS MULTIPLE MODEL RUNS BEHIND IT...AND AT 08Z
LXN CAME IN WITH FLURRIES. USED A 50-50 BLEND OF THE 00Z/06Z NAM
POPS TO TRACK THIS THRU THE SRN HALF OF THE FCST AREA.
RADAR IS IN VCP-31 TO PICK UP THIS LIGHT ACTIVITY.
THE RAP AND OTHER GUIDANCE TAKES THIS LOW ESE ACROSS FURNAS
COUNTY AND NRN KS TO SLN BY 16Z. EXPECT ANY FLURRY ACTIVITY TO BE
DONE BY THAT POINT.
TODAY: A FEW FLURRIES MAY LINGER HERE AND THERE S OF I-80 THRU
MID-MORNING. OTHERWISE...VARIABLE CLOUDS THIS MORNING WILL GIVE
WAY TO M/SUNNY THIS AFTERNOON...WHEN NW WINDS COULD GUST UP TO 20
MPH. USED THE WEIGHTED CONSENSUS OF THE 3 BEST-VERIFYING GUIDANCE
FOR TEMPS /W/. HIGHS WILL BE 15F BELOW NORMAL. CONFIDENCE: HIGH
TONIGHT: CLEAR AND COLD. WINDS WILL GO CALM THIS EVENING AND THEN
BECOME LIGHT FROM THE SSW /UNDER 10 MPH/.
THERE IS UNCERTAINTY IN THE FCST TEMP CURVES. DRY AIR AND CALM
WINDS WILL RESULT IN A RAPID TEMP DROP IN THE EVENING...BEFORE
LEVELING OFF AND POSSIBLY RISING A LITTLE. THIS IS NOT CURRENTLY
DEPICTED... BUT IT IS ON THE TABLE. I DID FORCE THE CLIMO TEMP
CURVE DOWN FASTER IN THE EVENING HOURS. BIAS CORRECTED 2M TEMPS
AND THE PREVIOUS GID FCST WERE USED FOR LOWS /BC-RAWBLEND/.
CONFIDENCE IS ONLY AVERAGE ON LOWS AS IT IS UNCERTAIN HOW MUCH
WINDS WILL OFFSET NEARLY IDEAL RADIATING CONDITIONS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 341 AM CST TUE JAN 28 2014
THE WEATHER PATTERN WILL UNDERGO CHANGES DURING THE OUTER
PERIODS. WEDNESDAY IS STILL SHAPING UP TO BE THE WARMEST OF THE
WEEK AS THE COLD AIRMASS IS DISLODGED/SHIFTS EAST OF THE PLAINS
WITH A DEPARTING TROUGH. WARMER MOVES IN FROM THE WEST WITH RISING
HEIGHTS...AND MORE ZONAL FLOW AHEAD OF AN APPROACHING COLD FRONT
ADVANCING ACROSS THE DAKOTAS. SOUTHERLY LLVL FLOW INCREASES DURING
THE AFTN AHEAD OF A SURFACE TROUGH FM THE DAKOTAS ACROSS THE HIGH
PLAINS REGION. IN THE WARMER...DRIER AIRMASS WITH INCREASING
WINDS...NEAR CRITICAL FIRE WEATHER CONDITIONS ARE POSSIBLE
ESPECIALLY ACROSS OUR SW COUNTIES.
THE COLD FRONTAL BOUNDARY ADVANCES SOUTH INTO CENTRAL NEBRASKA
WEDNESDAY NIGHT AS THE UPPER WAVE CROSSES THE UPPER MIDWEST REGION
AND LIGHT SNOW CHANCES REMAIN ACROSS OUR NORTHERN ZONES ALONG THE
BAROCLINIC ZONE AND IN UPPER DYNAMICS. TEMPS WEDNESDAY NIGHT ARE
TRICKY WITH THE DRIER AIRMASS ORIENTED ACROSS OUR SE
ZONES...COLDER AIR ADVECTING IN FROM THE NORTH AND STEADY WINDS
BOTH AHEAD/BEHIND THE FRONT AND HAVE HELD LOWS IN THE 20S. SMALL
CHANCES FOR LIGHT SNOW SPREAD SOUTHEASTWARD AND LINGER INTO
THURSDAY MORNING UNTIL THE MID LEVEL TROUGH AXIS PASSES TO THE
EAST. MODELS DIFFER ON FRONTAL POSITION FOR THURSDAY WITH THE NAM
NOT QUITE AS FAR SOUTH/SOUTHWEST WITH THE BOUNDARY AS THE
GFS/ECMWF. HAVE WENT WITH A MODEL BLEND FOR THURSDAY HIGHS RANGING
FM THE 20S IN OUR NE COUNTIES TO THE 40S IN THE SW.
THE WEATHER PATTERN BECOMES MORE ACTIVE DURING THE LATTER PART OF
THE WORKWEEK IN PROGRESSIVE WESTERLY FLOW AS THE JET STREAM SHIFTS
ACROSS THE MIDDLE PORTION OF THE CONUS. CHANCES FOR PCPN/SNOW
INCREASE AT THE END OF THE WEEK...GENERALLY CENTERED AROUND THE
FRIDAY TIME FRAME. MODELS ARE NOT IN COMPLETE AGREEMENT ON THE
TIMING OF THE WAVES AND PLACEMENT OF A SNOW BAND WITH PCPN
BEGINNING AS EARLY AS THURSDAY NIGHT AND CONTINUING INTO FRIDAY
NIGHT...AND THIS WILL NEED TO BE RESOLVED WITH TIME. THIS BEING
SAID...AT LEAST SOME LIGHT SNOW AND ACCUMULATIONS ARE POSSIBLE AT
THE END OF THE WORKWEEK.
THE FORECAST DRIES OUT OVER THE WEEKEND AS THE TROUGH AXIS PASSES
AND A SURFACE RIDGE AXIS SETTLES IN SATURDAY. THE RIDGE AXIS
SLIDES EAST SUNDAY AND THE PATTERN ALOFT BEGINS TO TRANSITION
SOUTHWESTERLY AHEAD OF A TROUGH TRANSLATING EASTWARD FM THE DESERT
SW EARLY NEXT WEEK. DID NOT DEVIATE FM THE EXTENDED INIT WITH PCPN
CHCS RETURNING ON MONDAY BUT UNCERTAINTY REMAINS ON WHERE THIS
SYSTEM WILL ULTIMATELY TRACK.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 341 AM CST TUE JAN 28 2014
...A NEW AND COLDER PATTERN IS NOW ESTABLISHED WITH THE COLD
BEGINNING TO EASE TODAY AND A NICE JUMP TOMORROW BUT THEN IT/S
BACK TO MORE COLD...
ALOFT: A TROF WAS MOVING THRU THE CNTRL PLAINS EARLY THIS
MORNING. IT WILL DEPART TO THE E TODAY WITH NNW FLOW GRADUALLY
BECOMING ANTICYCLONIC TONIGHT. HEIGHTS WILL RISE ABOUT 50M TODAY
AND ROUGHLY 100M TONIGHT.
SURFACE: EXPANSIVE HIGH PRES STRETCHED FROM MT-NE-IL. THIS HIGH
WAS SLOWLY SINKING S AND WILL SETTLE OVER TX AND THE GULF COAST
TONIGHT.
OVERALL...QUIET WX THRU TONIGHT.
NOW THRU SUNRISE: VARIABLE CLOUDS. SURFACE OBS SHOW A WEAK LOW
BETWEEN LBF-IML-MCK-LXN. MULTIPLE HI-RES MODELS DEVELOP A BURST
OF LIGHT SNOW /-SN/ OVER N-CNTRL KS AS THIS LOW DEPARTS WITH THE
UPPER TROF. THIS HAS MULTIPLE MODEL RUNS BEHIND IT...AND AT 08Z
LXN CAME IN WITH FLURRIES. USED A 50-50 BLEND OF THE 00Z/06Z NAM
POPS TO TRACK THIS THRU THE SRN HALF OF THE FCST AREA.
RADAR IS IN VCP-31 TO PICK UP THIS LIGHT ACTIVITY.
THE RAP AND OTHER GUIDANCE TAKES THIS LOW ESE ACROSS FURNAS
COUNTY AND NRN KS TO SLN BY 16Z. EXPECT ANY FLURRY ACTIVITY TO BE
DONE BY THAT POINT.
TODAY: A FEW FLURRIES MAY LINGER HERE AND THERE S OF I-80 THRU
MID-MORNING. OTHERWISE...VARIABLE CLOUDS THIS MORNING WILL GIVE
WAY TO M/SUNNY THIS AFTERNOON...WHEN NW WINDS COULD GUST UP TO 20
MPH. USED THE WEIGHTED CONSENSUS OF THE 3 BEST-VERIFYING GUIDANCE
FOR TEMPS /W/. HIGHS WILL BE 15F BELOW NORMAL. CONFIDENCE: HIGH
TONIGHT: CLEAR AND COLD. WINDS WILL GO CALM THIS EVENING AND THEN
BECOME LIGHT FROM THE SSW /UNDER 10 MPH/.
THERE IS UNCERTAINTY IN THE FCST TEMP CURVES. DRY AIR AND CALM
WINDS WILL RESULT IN A RAPID TEMP DROP IN THE EVENING...BEFORE
LEVELING OFF AND POSSIBLY RISING A LITTLE. THIS IS NOT CURRENTLY
DEPICTED... BUT IT IS ON THE TABLE. I DID FORCE THE CLIMO TEMP
CURVE DOWN FASTER IN THE EVENING HOURS. BIAS CORRECTED 2M TEMPS
AND THE PREVIOUS GID FCST WERE USED FOR LOWS /BC-RAWBLEND/.
CONFIDENCE IS ONLY AVERAGE ON LOWS AS IT IS UNCERTAIN HOW MUCH
WINDS WILL OFFSET NEARLY IDEAL RADIATING CONDITIONS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 341 AM CST TUE JAN 28 2014
THE WEATHER PATTERN WILL UNDERGO CHANGES DURING THE OUTER
PERIODS. WEDNESDAY IS STILL SHAPING UP TO BE THE WARMEST OF THE
WEEK AS THE COLD AIRMASS IS DISLODGED/SHIFTS EAST OF THE PLAINS
WITH A DEPARTING TROUGH. WARMER MOVES IN FROM THE WEST WITH RISING
HEIGHTS...AND MORE ZONAL FLOW AHEAD OF AN APPROACHING COLD FRONT
ADVANCING ACROSS THE DAKOTAS. SOUTHERLY LLVL FLOW INCREASES DURING
THE AFTN AHEAD OF A SURFACE TROUGH FM THE DAKOTAS ACROSS THE HIGH
PLAINS REGION. IN THE WARMER...DRIER AIRMASS WITH INCREASING
WINDS...NEAR CRITICAL FIRE WEATHER CONDITIONS ARE POSSIBLE
ESPECIALLY ACROSS OUR SW COUNTIES.
THE COLD FRONTAL BOUNDARY ADVANCES SOUTH INTO CENTRAL NEBRASKA
WEDNESDAY NIGHT AS THE UPPER WAVE CROSSES THE UPPER MIDWEST REGION
AND LIGHT SNOW CHANCES REMAIN ACROSS OUR NORTHERN ZONES ALONG THE
BAROCLINIC ZONE AND IN UPPER DYNAMICS. TEMPS WEDNESDAY NIGHT ARE
TRICKY WITH THE DRIER AIRMASS ORIENTED ACROSS OUR SE
ZONES...COLDER AIR ADVECTING IN FROM THE NORTH AND STEADY WINDS
BOTH AHEAD/BEHIND THE FRONT AND HAVE HELD LOWS IN THE 20S. SMALL
CHANCES FOR LIGHT SNOW SPREAD SOUTHEASTWARD AND LINGER INTO
THURSDAY MORNING UNTIL THE MID LEVEL TROUGH AXIS PASSES TO THE
EAST. MODELS DIFFER ON FRONTAL POSITION FOR THURSDAY WITH THE NAM
NOT QUITE AS FAR SOUTH/SOUTHWEST WITH THE BOUNDARY AS THE
GFS/ECMWF. HAVE WENT WITH A MODEL BLEND FOR THURSDAY HIGHS RANGING
FM THE 20S IN OUR NE COUNTIES TO THE 40S IN THE SW.
THE WEATHER PATTERN BECOMES MORE ACTIVE DURING THE LATTER PART OF
THE WORKWEEK IN PROGRESSIVE WESTERLY FLOW AS THE JET STREAM SHIFTS
ACROSS THE MIDDLE PORTION OF THE CONUS. CHANCES FOR PCPN/SNOW
INCREASE AT THE END OF THE WEEK...GENERALLY CENTERED AROUND THE
FRIDAY TIME FRAME. MODELS ARE NOT IN COMPLETE AGREEMENT ON THE
TIMING OF THE WAVES AND PLACEMENT OF A SNOW BAND WITH PCPN
BEGINNING AS EARLY AS THURSDAY NIGHT AND CONTINUING INTO FRIDAY
NIGHT...AND THIS WILL NEED TO BE RESOLVED WITH TIME. THIS BEING
SAID...AT LEAST SOME LIGHT SNOW AND ACCUMULATIONS ARE POSSIBLE AT
THE END OF THE WORKWEEK.
THE FORECAST DRIES OUT OVER THE WEEKEND AS THE TROUGH AXIS PASSES
AND A SURFACE RIDGE AXIS SETTLES IN SATURDAY. THE RIDGE AXIS
SLIDES EAST SUNDAY AND THE PATTERN ALOFT BEGINS TO TRANSITION
SOUTHWESTERLY AHEAD OF A TROUGH TRANSLATING EASTWARD FM THE DESERT
SW EARLY NEXT WEEK. DID NOT DEVIATE FM THE EXTENDED INIT WITH PCPN
CHCS RETURNING ON MONDAY BUT UNCERTAINTY REMAINS ON WHERE THIS
SYSTEM WILL ULTIMATELY TRACK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1144 AM CST TUE JAN 28 2014
VFR CONDITIONS ARE EXPECTED THROUGHOUT THE TAF VALID PERIOD. THERE
WILL BE A WIND SHIFT LATER THIS EVENING FROM A LIGHT NORTHWEST
WIND TO A LIGHT SOUTHWEST WIND AND THEN INCREASING BREEZES DURING
THE DAY TOMORROW OUT OF THE SOUTHWEST.
&&
.FIRE WEATHER...
ISSUED AT 341 AM CST TUE JAN 28 2014
ON WEDNESDAY...NEAR CRITICAL FIRE WEATHER CONDITIONS ARE FORECAST
FOR LOCATIONS PRIMARILY WEST OF A LINE FROM LEXINGTON NEBRASKA TO
BELOIT KANSAS. THE AIRMASS WILL BE DRY AND MILD IN THE AFTERNOON
AND LOW RELATIVE HUMIDITIES ARE FORECAST TO RANGE FROM 18 TO 25
PERCENT. SOUTHWESTERLY WINDS WILL INCREASE WITH GUSTS OF 20 TO 25
MPH POSSIBLE. CURRENT CONDITIONS ARE STILL MARGINAL FOR OBTAINING
RED FLAG WARNING CRITERIA FOR THE DURATION NEEDED AND WILL
CONTINUE TO MENTION NEAR CRITICAL CONDITIONS IN THE HWO.
&&
.CLIMATE...
ISSUED AT 341 AM CST TUE JAN 28 2014
THIS DEC-JAN COMBINED "COULD" BE AMONG THE TOP 10 DRIEST AT GRAND
ISLAND. THERE ARE PRECIP CHANCES IN THE FCST ON THE 30TH AND 31ST
SO THIS IS NOT IN THE BAG YET. AS THINGS STAND NOW...
GRI PRECIP /LIQUID EQUIVALENT/ RANKING FOR DEC-JAN AS OF 12 AM...
1 0.12 1960-61
2 0.14 1996-97
3 0.20 1963-64
4 0.25 2013-14
5 0.27 1985-86
THE LAST MEANINGFUL PRECIP AT GRI WAS THE 0.90 OF RAIN BACK ON NOV
5TH. IF WE EXTEND THIS DRY SPELL BACK TO 11/6...THE RANKING IS AS
FOLLOWS...
1 0.32 2013-14
2 0.36 1938-39
3 0.45 1963-64
4 0.46 1980-81
5 0.47 1986-87
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...HALBLAUB
LONG TERM...FAY
AVIATION...WESELY
CLIMATE...HALBLAUB
AREA FORECAST DISCUSSION
NWS HASTINGS NE
537 AM CST TUE JAN 28 2014
.UPDATE...
ISSUED AT 536 AM CST TUE JAN 28 2014
NO SUBSTANTIVE CHANGES NEEDED FOR THIS ESTF UPDATE. HOURLY TEMP/
DWPT/WIND WERE REFRESHED WITH CONSENSUS OF SHORT-TERM GUIDANCE.
FCST DWPTS ARE RUNNING A LITTLE ABOVE REALITY...BUT THIS HAS BEEN
CORRECTED.
THE SFC LOW IS NOW OVER HARLAN COUNTY AND HEADING ESE. SKIES HAVE
LARGELY CLEARED IN ITS WAKE. THE ONLY CLOUDS WE/VE NOTED ARE AT
BBW. THE SUN WILL HAVE TO MAKE IT OVER THE BATCH OF CLOUDS
ASSOCIATED WITH THE LOW. BEYOND THAT...LOOKS LIKE A NICE DAY WITH
THE EXTREME COLD OF YESTERDAY EASING A BIT.
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 341 AM CST TUE JAN 28 2014
...A NEW AND COLDER PATTERN IS NOW ESTABLISHED WITH THE COLD
BEGINNING TO EASE TODAY AND A NICE JUMP TOMORROW BUT THEN IT/S
BACK TO MORE COLD...
ALOFT: A TROF WAS MOVING THRU THE CNTRL PLAINS EARLY THIS
MORNING. IT WILL DEPART TO THE E TODAY WITH NNW FLOW GRADUALLY
BECOMING ANTICYCLONIC TONIGHT. HEIGHTS WILL RISE ABOUT 50M TODAY
AND ROUGHLY 100M TONIGHT.
SURFACE: EXPANSIVE HIGH PRES STRETCHED FROM MT-NE-IL. THIS HIGH
WAS SLOWLY SINKING S AND WILL SETTLE OVER TX AND THE GULF COAST
TONIGHT.
OVERALL...QUIET WX THRU TONIGHT.
NOW THRU SUNRISE: VARIABLE CLOUDS. SURFACE OBS SHOW A WEAK LOW
BETWEEN LBF-IML-MCK-LXN. MULTIPLE HI-RES MODELS DEVELOP A BURST
OF LIGHT SNOW /-SN/ OVER N-CNTRL KS AS THIS LOW DEPARTS WITH THE
UPPER TROF. THIS HAS MULTIPLE MODEL RUNS BEHIND IT...AND AT 08Z
LXN CAME IN WITH FLURRIES. USED A 50-50 BLEND OF THE 00Z/06Z NAM
POPS TO TRACK THIS THRU THE SRN HALF OF THE FCST AREA.
RADAR IS IN VCP-31 TO PICK UP THIS LIGHT ACTIVITY.
THE RAP AND OTHER GUIDANCE TAKES THIS LOW ESE ACROSS FURNAS
COUNTY AND NRN KS TO SLN BY 16Z. EXPECT ANY FLURRY ACTIVITY TO BE
DONE BY THAT POINT.
TODAY: A FEW FLURRIES MAY LINGER HERE AND THERE S OF I-80 THRU
MID-MORNING. OTHERWISE...VARIABLE CLOUDS THIS MORNING WILL GIVE
WAY TO M/SUNNY THIS AFTERNOON...WHEN NW WINDS COULD GUST UP TO 20
MPH. USED THE WEIGHTED CONSENSUS OF THE 3 BEST-VERIFYING GUIDANCE
FOR TEMPS /W/. HIGHS WILL BE 15F BELOW NORMAL. CONFIDENCE: HIGH
TONIGHT: CLEAR AND COLD. WINDS WILL GO CALM THIS EVENING AND THEN
BECOME LIGHT FROM THE SSW /UNDER 10 MPH/.
THERE IS UNCERTAINTY IN THE FCST TEMP CURVES. DRY AIR AND CALM
WINDS WILL RESULT IN A RAPID TEMP DROP IN THE EVENING...BEFORE
LEVELING OFF AND POSSIBLY RISING A LITTLE. THIS IS NOT CURRENTLY
DEPICTED... BUT IT IS ON THE TABLE. I DID FORCE THE CLIMO TEMP
CURVE DOWN FASTER IN THE EVENING HOURS. BIAS CORRECTED 2M TEMPS
AND THE PREVIOUS GID FCST WERE USED FOR LOWS /BC-RAWBLEND/.
CONFIDENCE IS ONLY AVERAGE ON LOWS AS IT IS UNCERTAIN HOW MUCH
WINDS WILL OFFSET NEARLY IDEAL RADIATING CONDITIONS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 341 AM CST TUE JAN 28 2014
THE WEATHER PATTERN WILL UNDERGO CHANGES DURING THE OUTER
PERIODS. WEDNESDAY IS STILL SHAPING UP TO BE THE WARMEST OF THE
WEEK AS THE COLD AIRMASS IS DISLODGED/SHIFTS EAST OF THE PLAINS
WITH A DEPARTING TROUGH. WARMER MOVES IN FROM THE WEST WITH RISING
HEIGHTS...AND MORE ZONAL FLOW AHEAD OF AN APPROACHING COLD FRONT
ADVANCING ACROSS THE DAKOTAS. SOUTHERLY LLVL FLOW INCREASES DURING
THE AFTN AHEAD OF A SURFACE TROUGH FM THE DAKOTAS ACROSS THE HIGH
PLAINS REGION. IN THE WARMER...DRIER AIRMASS WITH INCREASING
WINDS...NEAR CRITICAL FIRE WEATHER CONDITIONS ARE POSSIBLE
ESPECIALLY ACROSS OUR SW COUNTIES.
THE COLD FRONTAL BOUNDARY ADVANCES SOUTH INTO CENTRAL NEBRASKA
WEDNESDAY NIGHT AS THE UPPER WAVE CROSSES THE UPPER MIDWEST REGION
AND LIGHT SNOW CHANCES REMAIN ACROSS OUR NORTHERN ZONES ALONG THE
BAROCLINIC ZONE AND IN UPPER DYNAMICS. TEMPS WEDNESDAY NIGHT ARE
TRICKY WITH THE DRIER AIRMASS ORIENTED ACROSS OUR SE
ZONES...COLDER AIR ADVECTING IN FROM THE NORTH AND STEADY WINDS
BOTH AHEAD/BEHIND THE FRONT AND HAVE HELD LOWS IN THE 20S. SMALL
CHANCES FOR LIGHT SNOW SPREAD SOUTHEASTWARD AND LINGER INTO
THURSDAY MORNING UNTIL THE MID LEVEL TROUGH AXIS PASSES TO THE
EAST. MODELS DIFFER ON FRONTAL POSITION FOR THURSDAY WITH THE NAM
NOT QUITE AS FAR SOUTH/SOUTHWEST WITH THE BOUNDARY AS THE
GFS/ECMWF. HAVE WENT WITH A MODEL BLEND FOR THURSDAY HIGHS RANGING
FM THE 20S IN OUR NE COUNTIES TO THE 40S IN THE SW.
THE WEATHER PATTERN BECOMES MORE ACTIVE DURING THE LATTER PART OF
THE WORKWEEK IN PROGRESSIVE WESTERLY FLOW AS THE JET STREAM SHIFTS
ACROSS THE MIDDLE PORTION OF THE CONUS. CHANCES FOR PCPN/SNOW
INCREASE AT THE END OF THE WEEK...GENERALLY CENTERED AROUND THE
FRIDAY TIME FRAME. MODELS ARE NOT IN COMPLETE AGREEMENT ON THE
TIMING OF THE WAVES AND PLACEMENT OF A SNOW BAND WITH PCPN
BEGINNING AS EARLY AS THURSDAY NIGHT AND CONTINUING INTO FRIDAY
NIGHT...AND THIS WILL NEED TO BE RESOLVED WITH TIME. THIS BEING
SAID...AT LEAST SOME LIGHT SNOW AND ACCUMULATIONS ARE POSSIBLE AT
THE END OF THE WORKWEEK.
THE FORECAST DRIES OUT OVER THE WEEKEND AS THE TROUGH AXIS PASSES
AND A SURFACE RIDGE AXIS SETTLES IN SATURDAY. THE RIDGE AXIS
SLIDES EAST SUNDAY AND THE PATTERN ALOFT BEGINS TO TRANSITION
SOUTHWESTERLY AHEAD OF A TROUGH TRANSLATING EASTWARD FM THE DESERT
SW EARLY NEXT WEEK. DID NOT DEVIATE FM THE EXTENDED INIT WITH PCPN
CHCS RETURNING ON MONDAY BUT UNCERTAINTY REMAINS ON WHERE THIS
SYSTEM WILL ULTIMATELY TRACK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 536 AM CST TUE JAN 28 2014
TODAY: VFR. MULTI-LAYERED CLOUDS ARE DEPARTING TO THE S. FCST
SOUNDINGS SUGGEST THERE COULD BE ENOUGH MOISTURE FOR A FEW FAIR
WX STRATOCU TO DEVELOP WITH DAYTIME HEATING. LIGHT AND VARIABLE
WINDS WILL ORGANIZE FROM THE WNW AFTER 16Z AND AVERAGE 10-15 KTS.
CONFIDENCE: HIGH
TONIGHT: VFR SKC. WINDS WILL BECOME LIGHT AND VARIABLE AROUND 00Z
AND BY 03Z SHOULD DEVELOP FROM THE SW AND GRADUALLY INCREASE TO
4-9 KTS...HIGHEST TOWARD DAWN. CONFIDENCE: HIGH
&&
.FIRE WEATHER...
ISSUED AT 341 AM CST TUE JAN 28 2014
ON WEDNESDAY...NEAR CRITICAL FIRE WEATHER CONDITIONS ARE FORECAST
FOR LOCATIONS PRIMARILY WEST OF A LINE FROM LEXINGTON NEBRASKA TO
BELOIT KANSAS. THE AIRMASS WILL BE DRY AND MILD IN THE AFTERNOON
AND LOW RELATIVE HUMIDITIES ARE FORECAST TO RANGE FROM 18 TO 25
PERCENT. SOUTHWESTERLY WINDS WILL INCREASE WITH GUSTS OF 20 TO 25
MPH POSSIBLE. CURRENT CONDITIONS ARE STILL MARGINAL FOR OBTAINING
RED FLAG WARNING CRITERIA FOR THE DURATION NEEDED AND WILL
CONTINUE TO MENTION NEAR CRITICAL CONDITIONS IN THE HWO.
&&
.CLIMATE...
ISSUED AT 341 AM CST TUE JAN 28 2014
THIS DEC-JAN COMBINED "COULD" BE AMONG THE TOP 10 DRIEST AT GRAND
ISLAND. THERE ARE PRECIP CHANCES IN THE FCST ON THE 30TH AND 31ST
SO THIS IS NOT IN THE BAG YET. AS THINGS STAND NOW...
GRI PRECIP /LIQUID EQUIVALENT/ RANKING FOR DEC-JAN AS OF 12 AM...
1 0.12 1960-61
2 0.14 1996-97
3 0.20 1963-64
4 0.25 2013-14
5 0.27 1985-86
THE LAST MEANINGFUL PRECIP AT GRI WAS THE 0.90 OF RAIN BACK ON NOV
5TH. IF WE EXTEND THIS DRY SPELL BACK TO 11/6...THE RANKING IS AS
FOLLOWS...
1 0.32 2013-14
2 0.36 1938-39
3 0.45 1963-64
4 0.46 1980-81
5 0.47 1986-87
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...HALBLAUB
LONG TERM...FAY
AVIATION...HALBLAUB
FIRE WX...FAY
CLIMATE...HALBLAUB
AREA FORECAST DISCUSSION
NWS HASTINGS NE
341 AM CST TUE JAN 28 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 341 AM CST TUE JAN 28 2014
...A NEW AND COLDER PATTERN IS NOW ESTABLISHED WITH THE COLD
BEGINNING TO EASE TODAY AND A NICE JUMP TOMORROW BUT THEN IT/S
BACK TO MORE COLD...
ALOFT: A TROF WAS MOVING THRU THE CNTRL PLAINS EARLY THIS
MORNING. IT WILL DEPART TO THE E TODAY WITH NNW FLOW GRADUALLY
BECOMING ANTICYCLONIC TONIGHT. HEIGHTS WILL RISE ABOUT 50M TODAY
AND ROUGHLY 100M TONIGHT.
SURFACE: EXPANSIVE HIGH PRES STRETCHED FROM MT-NE-IL. THIS HIGH
WAS SLOWLY SINKING S AND WILL SETTLE OVER TX AND THE GULF COAST
TONIGHT.
OVERALL...QUIET WX THRU TONIGHT.
NOW THRU SUNRISE: VARIABLE CLOUDS. SURFACE OBS SHOW A WEAK LOW
BETWEEN LBF-IML-MCK-LXN. MULTIPLE HI-RES MODELS DEVELOP A BURST
OF LIGHT SNOW /-SN/ OVER N-CNTRL KS AS THIS LOW DEPARTS WITH THE
UPPER TROF. THIS HAS MULTIPLE MODEL RUNS BEHIND IT...AND AT 08Z
LXN CAME IN WITH FLURRIES. USED A 50-50 BLEND OF THE 00Z/06Z NAM
POPS TO TRACK THIS THRU THE SRN HALF OF THE FCST AREA.
RADAR IS IN VCP-31 TO PICK UP THIS LIGHT ACTIVITY.
THE RAP AND OTHER GUIDANCE TAKES THIS LOW ESE ACROSS FURNAS
COUNTY AND NRN KS TO SLN BY 16Z. EXPECT ANY FLURRY ACTIVITY TO BE
DONE BY THAT POINT.
TODAY: A FEW FLURRIES MAY LINGER HERE AND THERE S OF I-80 THRU
MID-MORNING. OTHERWISE...VARIABLE CLOUDS THIS MORNING WILL GIVE
WAY TO M/SUNNY THIS AFTERNOON...WHEN NW WINDS COULD GUST UP TO 20
MPH. USED THE WEIGHTED CONSENSUS OF THE 3 BEST-VERIFYING GUIDANCE
FOR TEMPS /W/. HIGHS WILL BE 15F BELOW NORMAL. CONFIDENCE: HIGH
TONIGHT: CLEAR AND COLD. WINDS WILL GO CALM THIS EVENING AND THEN
BECOME LIGHT FROM THE SSW /UNDER 10 MPH/.
THERE IS UNCERTAINTY IN THE FCST TEMP CURVES. DRY AIR AND CALM
WINDS WILL RESULT IN A RAPID TEMP DROP IN THE EVENING...BEFORE
LEVELING OFF AND POSSIBLY RISING A LITTLE. THIS IS NOT CURRENTLY
DEPICTED... BUT IT IS ON THE TABLE. I DID FORCE THE CLIMO TEMP
CURVE DOWN FASTER IN THE EVENING HOURS. BIAS CORRECTED 2M TEMPS
AND THE PREVIOUS GID FCST WERE USED FOR LOWS /BC-RAWBLEND/.
CONFIDENCE IS ONLY AVERAGE ON LOWS AS IT IS UNCERTAIN HOW MUCH
WINDS WILL OFFSET NEARLY IDEAL RADIATING CONDITIONS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 341 AM CST TUE JAN 28 2014
THE WEATHER PATTERN WILL UNDERGO CHANGES DURING THE OUTER
PERIODS. WEDNESDAY IS STILL SHAPING UP TO BE THE WARMEST OF THE
WEEK AS THE COLD AIRMASS IS DISLODGED/SHIFTS EAST OF THE PLAINS
WITH A DEPARTING TROUGH. WARMER MOVES IN FROM THE WEST WITH RISING
HEIGHTS...AND MORE ZONAL FLOW AHEAD OF AN APPROACHING COLD FRONT
ADVANCING ACROSS THE DAKOTAS. SOUTHERLY LLVL FLOW INCREASES DURING
THE AFTN AHEAD OF A SURFACE TROUGH FM THE DAKOTAS ACROSS THE HIGH
PLAINS REGION. IN THE WARMER...DRIER AIRMASS WITH INCREASING
WINDS...NEAR CRITICAL FIRE WEATHER CONDITIONS ARE POSSIBLE
ESPECIALLY ACROSS OUR SW COUNTIES.
THE COLD FRONTAL BOUNDARY ADVANCES SOUTH INTO CENTRAL NEBRASKA
WEDNESDAY NIGHT AS THE UPPER WAVE CROSSES THE UPPER MIDWEST REGION
AND LIGHT SNOW CHANCES REMAIN ACROSS OUR NORTHERN ZONES ALONG THE
BAROCLINIC ZONE AND IN UPPER DYNAMICS. TEMPS WEDNESDAY NIGHT ARE
TRICKY WITH THE DRIER AIRMASS ORIENTED ACROSS OUR SE
ZONES...COLDER AIR ADVECTING IN FROM THE NORTH AND STEADY WINDS
BOTH AHEAD/BEHIND THE FRONT AND HAVE HELD LOWS IN THE 20S. SMALL
CHANCES FOR LIGHT SNOW SPREAD SOUTHEASTWARD AND LINGER INTO
THURSDAY MORNING UNTIL THE MID LEVEL TROUGH AXIS PASSES TO THE
EAST. MODELS DIFFER ON FRONTAL POSITION FOR THURSDAY WITH THE NAM
NOT QUITE AS FAR SOUTH/SOUTHWEST WITH THE BOUNDARY AS THE
GFS/ECMWF. HAVE WENT WITH A MODEL BLEND FOR THURSDAY HIGHS RANGING
FM THE 20S IN OUR NE COUNTIES TO THE 40S IN THE SW.
THE WEATHER PATTERN BECOMES MORE ACTIVE DURING THE LATTER PART
OF THE WORKWEEK IN PROGRESSIVE WESTERLY FLOW AS THE JET STREAM
SHIFTS ACROSS THE MIDDLE PORTION OF THE CONUS. CHANCES FOR
PCPN/SNOW INCREASE AT THE END OF THE WEEK...GENERALLY CENTERED
AROUND THE FRIDAY TIME FRAME. MODELS ARE NOT IN COMPLETE AGREEMENT
ON THE TIMING OF THE WAVES AND PLACEMENT OF A SNOW BAND WITH PCPN
BEGINNING AS EARLY AS THURSDAY NIGHT AND CONTINUING INTO FRIDAY
NIGHT...AND THIS WILL NEED TO BE RESOLVED WITH TIME. THIS BEING
SAID...AT LEAST SOME LIGHT SNOW AND ACCUMULATIONS ARE POSSIBLE AT
THE END OF THE WORKWEEK.
THE FORECAST DRIES OUT OVER THE WEEKEND AS THE TROUGH AXIS PASSES
AND A SURFACE RIDGE AXIS SETTLES IN SATURDAY. THE RIDGE AXIS
SLIDES EAST SUNDAY AND THE PATTERN ALOFT BEGINS TO TRANSITION
SOUTHWESTERLY AHEAD OF A TROUGH TRANSLATING EASTWARD FM THE DESERT
SW EARLY NEXT WEEK. DID NOT DEVIATE FM THE EXTENDED INIT WITH PCPN
CHCS RETURNING ON MONDAY BUT UNCERTAINTY REMAINS ON WHERE THIS
SYSTEM WILL ULTIMATELY TRACK.
&&
.FIRE WEATHER...
ISSUED AT 341 AM CST TUE JAN 28 2014
ON WEDNESDAY...NEAR CRITICAL FIRE WEATHER CONDITIONS ARE FORECAST
FOR LOCATIONS PRIMARILY WEST OF A LINE FROM LEXINGTON NEBRASKA TO
BELOIT KANSAS. THE AIRMASS WILL BE DRY AND MILD IN THE AFTERNOON
AND LOW RELATIVE HUMIDITIES ARE FORECAST TO RANGE FROM 18 TO 25
PERCENT. SOUTHWESTERLY WINDS WILL INCREASE WITH GUSTS OF 20 TO 25
MPH POSSIBLE. CURRENT CONDITIONS ARE STILL MARGINAL FOR OBTAINING
RED FLAG WARNING CRITERIA FOR THE DURATION NEEDED AND WILL
CONTINUE TO MENTION NEAR CRITICAL CONDITIONS IN THE HWO.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1224 AM CST TUE JAN 28 2014
REST OF TONIGHT: VFR WITH VARIABLE MID-LEVEL CIGS AND VERY LIGHT
WINDS. CONFIDENCE: HIGH
TUE: VFR WITH DECREASING CLOUDS. SHOULD BE JUST A FEW STRATOCU BY
AFTERNOON. WINDS WILL DEVELOP FROM THE WNW AND AVERAGE 10 KTS.
CONFIDENCE: HIGH
TUE EVE: VFR SKC. CALM WINDS 00Z-03Z WILL BECOME SW LESS THAN 10
KTS AFTER 03Z. CONFIDENCE: HIGH
&&
.CLIMATE...
ISSUED AT 341 AM CST TUE JAN 28 2014
THIS DEC-JAN COMBINED "COULD" BE AMONG THE TOP 10 DRIEST AT GRAND
ISLAND. THERE ARE PRECIP CHANCES IN THE FCST ON THE 30TH AND 31ST
SO THIS IS NOT IN THE BAG YET. AS THINGS STAND NOW...
GRI PRECIP /LIQUID EQUIVALENT/ RANKING FOR DEC-JAN AS OF 12 AM...
1 0.12 1960-61
2 0.14 1996-97
3 0.20 1963-64
4 0.25 2013-14
5 0.27 1985-86
THE LAST MEANINGFUL PRECIP AT GRI WAS THE 0.90 OF RAIN BACK ON NOV
5TH. IF WE EXTEND THIS DRY SPELL BACK TO 11/6...THE RANKING IS AS
FOLLOWS...
1 0.32 2013-14
2 0.36 1938-39
3 0.45 1963-64
4 0.46 1980-81
5 0.47 1986-87
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...HALBLAUB
LONG TERM...FAY
FIRE WX...FAY
AVIATION...HALBLAUB
CLIMATE...HALBLAUB
AREA FORECAST DISCUSSION
NWS BISMARCK ND
103 PM CST TUE JAN 28 2014
.UPDATE...
ISSUED AT 103 PM CST TUE JAN 28 2014
NO UPDATES PLANNED THIS EARLY AFTERNOON OTHER THAN TO LET THE WIND
CHILL ADVISORY/WARNING EXPIRE AS PLANNED AT 1 PM.
UPDATE ISSUED AT 1001 AM CST TUE JAN 28 2014
NO SIGNIFICANT UPDATES TO THE FORECAST THIS MORNING. ARCTIC HIGH
PRESSURE CONTINUES TO SLIDE SOUTHEAST ACROSS THE REGION. CURRENT
WIND CHILLS RANGING FROM AROUND 25 BELOW SOUTHWEST TO 35 TO 40
BELOW NORTHEAST. SHOULD BE ABLE TO CANCEL THE WIND CHILL
HIGHLIGHTS WITH THE NEXT UPDATE...IF NOT SOONER. WILL ALSO TAKE A
CLOSER LOOK AT FORECAST HIGHS AT THAT TIME.
UPDATE ISSUED AT 629 AM CST TUE JAN 28 2014
NARROW BAND OF LOW/MID CLOUDS ACROSS SOUTHWEST MANT/NW ND
CONTINUES TO MOVE NEARLY STEADY STATE INTO NORTH DAKOTA. NWS
RADARS STILL NOT PICKING UP MUCH FOR PRECIP FROM THE CLOUDS. WILL
LEAVE THE ISOLATED FLURRIES IN THE FORECAST. TUESDAYS MORNING LOWS
NOT QUIT AS COLD AS FORECAST CURRENTLY 3 TO 5 DEGREES ABOVE
TRENDS. STILL HAVE 2 TO 3 HOURS POTENTIAL COOLING. WIND CHILL
WARNINGS/ADVISORIES CONTINUE.JUST MADE SOME CLOUDS ADJUSTMENTS
NORTH FOR A MORE PERSISTENT CLOUDS BAND THIS MORNING.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 325 AM CST TUE JAN 28 2014
FORECAST HIGHLIGHTS IN THE SHORT TERM PERIOD WILL BE WIND CHILL
HEADLINES THIS MORNING...THEN A WARMING TREND THIS AFTERNOON INTO
TONIGHT.
CURRENTLY...NORTHERLY FLOW ALOFT REMAINS OVER THE NORTHERN PLAINS
WITH SURFACE HIGH PRESSURE BUILDING INTO WESTERN NORTH DAKOTA. AN
AREA OF BKN-OVC CIGS AROUND 4-5K FEET AGL ALONG THE
MANITOBA/SASKATCHEWAN BORDER CONTINUES TO SLOWLY MOVE SOUTH WITH
THE MEAN FLOW. STILL SHOWING OBS UNDERNEATH THESE CLOUDS REPORTING
LIGHT SNOW WITH NO IMPACT TO VISIBILITIES. THESE CLOUDS APPEAR TO
BE ASSOCIATED WITH WAA ON THE BACKSIDE OF THE SFC RIDGE AND A
SUBTLE MID LEVEL IMPULSE. USED THE LATEST RAP 925-850MB RH
DEPICTION...WHICH SEEMS TO BEST CAPTURE THE CURRENT AERIAL
COVERAGE AND TIMING OF THESE CLOUDS. THUS INCREASED SKY COVER
NORTH AND EAST NOW - 18Z AND MENTIONED ISOLATED FLURRIES ACROSS MY
NORTHEAST WHERE/WHEN THE HR MODELS TRACK THESE CLOUDS.
RIDGE OF SFC HIGH PRESSURE REMAINS OVER WESTERN AND CENTRAL NORTH
DAKOTA THROUGH TODAY. AS MENTIONED ABOVE...WAA IS OCCURRING ON THE
BACKSIDE OF THE RIDGE AND WILL CONTINUE INTO THIS AFTERNOON. THUS
DESPITE A COLD START THIS MORNING WITH SUBZERO TEMPERATURES...WILL
SEE AFTERNOON TEMPERATURES CLIMB TO POSITIVE READINGS ALL
LOCATIONS.
STRONG EMBEDDED S/WV DROPS SOUTH ACROSS SOUTH CENTRAL CANADA
TONIGHT...WITH AN ASSOCIATED SFC LOW DEVELOPING ACROSS CENTRAL
SASKATCHEWAN IN THE EVENING MOVING TOWARDS LAKE WINNIPEG
OVERNIGHT. WAA RAMPS UP AS WE REMAIN IN THE WARM SECTOR OF THE LOW
THROUGH 12Z. A 10-15 MPH SOUTHWEST MIXING WIND WILL ALLOW
TEMPERATURES FROM THIS AFTERNOON TO REMAIN STEADY OR RISE TONIGHT
BE SEVERAL DEGREES.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 325 AM CST TUE JAN 28 2014
THE MAIN FEATURE IN THE EXTENDED PERIOD CONTINUES TO BE THE LARGE
COLD UPPER LOW OVER CENTRAL AND EASTERN CANADA. THIS WILL BRING A
STEADY STREAM OF WEAK IMPULSES/COLD FRONTS THROUGH THE NORTHERN
PLAINS. MOISTURE IS QUITE LIMITED AND THE MODELS HAVE DEPICTED DRY
WEATHER THROUGH THE EXTENDED. WHILE THIS APPEARS REASONABLE EACH
IMPULSE COULD BRING SOME TRACE AMOUNTS OF FLURRIES OR LIGHT SNOW.
RATHER THAN BROADBRUSH 15-20 POPS ACROSS THE REGION THROUGH THE
PERIOD LEFT THE EXTENDED DRY EXCEPT FOR A BRUSHING OF LIGHT SNOW
ACROSS THE SOUTHWEST ON WEDNESDAY AND WEDNESDAY NIGHT. THE
ACCUMULATING SNOWS SHOW REMAINS WEST AND SOUTH OF THE REGION THOUGH.
TEMPERATURES SHOULD REMAIN NEAR OR BELOW NORMAL FOR THIS TIME OF THE
YEAR. THIS WILL BE A BREEZY PERIOD WITH COLD THE COLD FRONTAL
PASSAGES. FOCUSED ON THURSDAY/THURSDAY NIGHT IN THE HAZARDOUS
WEATHER OUTLOOK FOR SOME CRITICAL WIND CHILL TEMPERATURES INTO THE
ADVISORY CATEGORY NORTH AND EAST. DID NOT SEE ANY TARGETS OF
OPPORTUNITY TO DEPART FROM THE ALLBLEND GUIDANCE TODAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 103 PM CST TUE JAN 28 2014
VFR CONDITIONS EXPECTED AT ALL TAF SITES THIS AFTERNOON AND TONIGHT
WITH A LIGHT WEST TO SOUTHWEST FLOW. A COLD FRONT WILL MOVE SOUTH
THROUGH THE AREA ON WEDNESDAY. THIS WILL BRING INCREASING CLOUDS
FROM NORTHWEST TO SOUTHEAST LATE TONIGHT AND WEDNESDAY MORNING.
AREAS OF MVFR CEILINGS COULD MOVE INTO MINOT AND WILLISTON AFTER 15Z
WEDNESDAY.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...TWH
SHORT TERM...NH
LONG TERM...WAA
AVIATION...TWH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1001 AM CST TUE JAN 28 2014
.UPDATE...
ISSUED AT 1001 AM CST TUE JAN 28 2014
NO SIGNIFICANT UPDATES TO THE FORECAST THIS MORNING. ARCTIC HIGH
PRESSURE CONTINUES TO SLIDE SOUTHEAST ACROSS THE REGION. CURRENT
WIND CHILLS RANGING FROM AROUND 25 BELOW SOUTHWEST TO 35 TO 40
BELOW NORTHEAST. SHOULD BE ABLE TO CANCEL THE WIND CHILL
HIGHLIGHTS WITH THE NEXT UPDATE...IF NOT SOONER. WILL ALSO TAKE A
CLOSER LOOK AT FORECAST HIGHS AT THAT TIME.
UPDATE ISSUED AT 629 AM CST TUE JAN 28 2014
NARROW BAND OF LOW/MID CLOUDS ACROSS SOUTHWEST MANT/NW ND
CONTINUES TO MOVE NEARLY STEADY STATE INTO NORTH DAKOTA. NWS
RADARS STILL NOT PICKING UP MUCH FOR PRECIP FROM THE CLOUDS. WILL
LEAVE THE ISOLATED FLURRIES IN THE FORECAST. TUESDAYS MORNING LOWS
NOT QUIT AS COLD AS FORECAST CURRENTLY 3 TO 5 DEGREES ABOVE
TRENDS. STILL HAVE 2 TO 3 HOURS POTENTIAL COOLING. WIND CHILL
WARNINGS/ADVISORIES CONTINUE.JUST MADE SOME CLOUDS ADJUSTMENTS
NORTH FOR A MORE PERSISTENT CLOUDS BAND THIS MORNING.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 325 AM CST TUE JAN 28 2014
FORECAST HIGHLIGHTS IN THE SHORT TERM PERIOD WILL BE WIND CHILL
HEADLINES THIS MORNING...THEN A WARMING TREND THIS AFTERNOON INTO
TONIGHT.
CURRENTLY...NORTHERLY FLOW ALOFT REMAINS OVER THE NORTHERN PLAINS
WITH SURFACE HIGH PRESSURE BUILDING INTO WESTERN NORTH DAKOTA. AN
AREA OF BKN-OVC CIGS AROUND 4-5K FEET AGL ALONG THE
MANITOBA/SASKATCHEWAN BORDER CONTINUES TO SLOWLY MOVE SOUTH WITH
THE MEAN FLOW. STILL SHOWING OBS UNDERNEATH THESE CLOUDS REPORTING
LIGHT SNOW WITH NO IMPACT TO VISIBILITIES. THESE CLOUDS APPEAR TO
BE ASSOCIATED WITH WAA ON THE BACKSIDE OF THE SFC RIDGE AND A
SUBTLE MID LEVEL IMPULSE. USED THE LATEST RAP 925-850MB RH
DEPICTION...WHICH SEEMS TO BEST CAPTURE THE CURRENT AERIAL
COVERAGE AND TIMING OF THESE CLOUDS. THUS INCREASED SKY COVER
NORTH AND EAST NOW - 18Z AND MENTIONED ISOLATED FLURRIES ACROSS MY
NORTHEAST WHERE/WHEN THE HR MODELS TRACK THESE CLOUDS.
RIDGE OF SFC HIGH PRESSURE REMAINS OVER WESTERN AND CENTRAL NORTH
DAKOTA THROUGH TODAY. AS MENTIONED ABOVE...WAA IS OCCURRING ON THE
BACKSIDE OF THE RIDGE AND WILL CONTINUE INTO THIS AFTERNOON. THUS
DESPITE A COLD START THIS MORNING WITH SUBZERO TEMPERATURES...WILL
SEE AFTERNOON TEMPERATURES CLIMB TO POSITIVE READINGS ALL
LOCATIONS.
STRONG EMBEDDED S/WV DROPS SOUTH ACROSS SOUTH CENTRAL CANADA
TONIGHT...WITH AN ASSOCIATED SFC LOW DEVELOPING ACROSS CENTRAL
SASKATCHEWAN IN THE EVENING MOVING TOWARDS LAKE WINNIPEG
OVERNIGHT. WAA RAMPS UP AS WE REMAIN IN THE WARM SECTOR OF THE LOW
THROUGH 12Z. A 10-15 MPH SOUTHWEST MIXING WIND WILL ALLOW
TEMPERATURES FROM THIS AFTERNOON TO REMAIN STEADY OR RISE TONIGHT
BE SEVERAL DEGREES.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 325 AM CST TUE JAN 28 2014
THE MAIN FEATURE IN THE EXTENDED PERIOD CONTINUES TO BE THE LARGE
COLD UPPER LOW OVER CENTRAL AND EASTERN CANADA. THIS WILL BRING A
STEADY STREAM OF WEAK IMPULSES/COLD FRONTS THROUGH THE NORTHERN
PLAINS. MOISTURE IS QUITE LIMITED AND THE MODELS HAVE DEPICTED DRY
WEATHER THROUGH THE EXTENDED. WHILE THIS APPEARS REASONABLE EACH
IMPULSE COULD BRING SOME TRACE AMOUNTS OF FLURRIES OR LIGHT SNOW.
RATHER THAN BROADBRUSH 15-20 POPS ACROSS THE REGION THROUGH THE
PERIOD LEFT THE EXTENDED DRY EXCEPT FOR A BRUSHING OF LIGHT SNOW
ACROSS THE SOUTHWEST ON WEDNESDAY AND WEDNESDAY NIGHT. THE
ACCUMULATING SNOWS SHOW REMAINS WEST AND SOUTH OF THE REGION THOUGH.
TEMPERATURES SHOULD REMAIN NEAR OR BELOW NORMAL FOR THIS TIME OF THE
YEAR. THIS WILL BE A BREEZY PERIOD WITH COLD THE COLD FRONTAL
PASSAGES. FOCUSED ON THURSDAY/THURSDAY NIGHT IN THE HAZARDOUS
WEATHER OUTLOOK FOR SOME CRITICAL WIND CHILL TEMPERATURES INTO THE
ADVISORY CATEGORY NORTH AND EAST. DID NOT SEE ANY TARGETS OF
OPPORTUNITY TO DEPART FROM THE ALLBLEND GUIDANCE TODAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1001 AM CST TUE JAN 28 2014
VFR CONDITIONS FORECAST THROUGH THE 18Z TAF PERIOD ALL TERMINALS.
AN AREA OF BKN-OVC MID LEVEL CLOUDS WILL MOVE SLOWLY SOUTH FROM
SOUTH CENTRAL CANADA INTO NORTHEAST NORTH DAKOTA NOW THROUGH 20Z.
IT APPEARS THIS AREA WILL MISS KMOT AND KJMS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
WIND CHILL ADVISORY UNTIL 1 PM CST /NOON MST/ THIS AFTERNOON FOR
NDZ009-017>020-031>035-040>046.
WIND CHILL WARNING UNTIL 1 PM CST THIS AFTERNOON FOR NDZ001>005-
010>013-021>023-025-036-037-047-048-050-051.
&&
$$
UPDATE...TWH
SHORT TERM...NH
LONG TERM...WAA
AVIATION...TWH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
636 AM CST TUE JAN 28 2014
.UPDATE...
ISSUED AT 629 AM CST TUE JAN 28 2014
NARROW BAND OF LOW/MID CLOUDS ACROSS SOUTHWEST MANT/NW ND
CONTINUES TO MOVE NEARLY STEADY STATE INTO NORTH DAKOTA. NWS
RADARS STILL NOT PICKING UP MUCH FOR PRECIP FROM THE CLOUDS. WILL
LEAVE THE ISOLATED FLURRIES IN THE FORECAST. TUESDAYS MORNING LOWS
NOT QUIT AS COLD AS FORECAST CURRENTLY 3 TO 5 DEGREES ABOVE
TRENDS. STILL HAVE 2 TO 3 HOURS POTENTIAL COOLING. WIND CHILL
WARNINGS/ADVISORIES CONTINUE.JUST MADE SOME CLOUDS ADJUSTMENTS
NORTH FOR A MORE PERSISTENT CLOUDS BAND THIS MORNING.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 325 AM CST TUE JAN 28 2014
FORECAST HIGHLIGHTS IN THE SHORT TERM PERIOD WILL BE WIND CHILL
HEADLINES THIS MORNING...THEN A WARMING TREND THIS AFTERNOON INTO
TONIGHT.
CURRENTLY...NORTHERLY FLOW ALOFT REMAINS OVER THE NORTHERN PLAINS
WITH SURFACE HIGH PRESSURE BUILDING INTO WESTERN NORTH DAKOTA. AN
AREA OF BKN-OVC CIGS AROUND 4-5K FEET AGL ALONG THE
MANITOBA/SASKATCHEWAN BORDER CONTINUES TO SLOWLY MOVE SOUTH WITH
THE MEAN FLOW. STILL SHOWING OBS UNDERNEATH THESE CLOUDS REPORTING
LIGHT SNOW WITH NO IMPACT TO VISIBILITIES. THESE CLOUDS APPEAR TO
BE ASSOCIATED WITH WAA ON THE BACKSIDE OF THE SFC RIDGE AND A
SUBTLE MID LEVEL IMPULSE. USED THE LATEST RAP 925-850MB RH
DEPICTION...WHICH SEEMS TO BEST CAPTURE THE CURRENT AERIAL
COVERAGE AND TIMING OF THESE CLOUDS. THUS INCREASED SKY COVER
NORTH AND EAST NOW - 18Z AND MENTIONED ISOLATED FLURRIES ACROSS MY
NORTHEAST WHERE/WHEN THE HR MODELS TRACK THESE CLOUDS.
RIDGE OF SFC HIGH PRESSURE REMAINS OVER WESTERN AND CENTRAL NORTH
DAKOTA THROUGH TODAY. AS MENTIONED ABOVE...WAA IS OCCURRING ON THE
BACKSIDE OF THE RIDGE AND WILL CONTINUE INTO THIS AFTERNOON. THUS
DESPITE A COLD START THIS MORNING WITH SUBZERO TEMPERATURES...WILL
SEE AFTERNOON TEMPERATURES CLIMB TO POSITIVE READINGS ALL
LOCATIONS.
STRONG EMBEDDED S/WV DROPS SOUTH ACROSS SOUTH CENTRAL CANADA
TONIGHT...WITH AN ASSOCIATED SFC LOW DEVELOPING ACROSS CENTRAL
SASKATCHEWAN IN THE EVENING MOVING TOWARDS LAKE WINNIPEG
OVERNIGHT. WAA RAMPS UP AS WE REMAIN IN THE WARM SECTOR OF THE LOW
THROUGH 12Z. A 10-15 MPH SOUTHWEST MIXING WIND WILL ALLOW
TEMPERATURES FROM THIS AFTERNOON TO REMAIN STEADY OR RISE TONIGHT
BE SEVERAL DEGREES.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 325 AM CST TUE JAN 28 2014
THE MAIN FEATURE IN THE EXTENDED PERIOD CONTINUES TO BE THE LARGE
COLD UPPER LOW OVER CENTRAL AND EASTERN CANADA. THIS WILL BRING A
STEADY STREAM OF WEAK IMPULSES/COLD FRONTS THROUGH THE NORTHERN
PLAINS. MOISTURE IS QUITE LIMITED AND THE MODELS HAVE DEPICTED DRY
WEATHER THROUGH THE EXTENDED. WHILE THIS APPEARS REASONABLE EACH
IMPULSE COULD BRING SOME TRACE AMOUNTS OF FLURRIES OR LIGHT SNOW.
RATHER THAN BROADBRUSH 15-20 POPS ACROSS THE REGION THROUGH THE
PERIOD LEFT THE EXTENDED DRY EXCEPT FOR A BRUSHING OF LIGHT SNOW
ACROSS THE SOUTHWEST ON WEDNESDAY AND WEDNESDAY NIGHT. THE
ACCUMULATING SNOWS SHOW REMAINS WEST AND SOUTH OF THE REGION THOUGH.
TEMPERATURES SHOULD REMAIN NEAR OR BELOW NORMAL FOR THIS TIME OF THE
YEAR. THIS WILL BE A BREEZY PERIOD WITH COLD THE COLD FRONTAL
PASSAGES. FOCUSED ON THURSDAY/THURSDAY NIGHT IN THE HAZARDOUS
WEATHER OUTLOOK FOR SOME CRITICAL WIND CHILL TEMPERATURES INTO THE
ADVISORY CATEGORY NORTH AND EAST. DID NOT SEE ANY TARGETS OF
OPPORTUNITY TO DEPART FROM THE ALLBLEND GUIDANCE TODAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 629 AM CST TUE JAN 28 2014
VFR CONDITIONS FORECAST THROUGH THE 12Z TAF PERIOD ALL TERMINALS. AN
AREA OF BKN-OVC MID LEVEL CLOUDS WILL MOVE SLOWLY SOUTH FROM SOUTH
CENTRAL CANADA INTO NORTHERN AND EASTERN NORTH DAKOTA NOW THROUGH
20Z. KMOT AND KJMS MAY SEE A BKN-OVC CIG AT AROUND 5K FEET AGL AND
IN ISOLATED LIGHT SNOW SHOWER THROUGH 20Z...BUT SHOULD NOT IMPACT
AVIATION.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
WIND CHILL ADVISORY UNTIL 1 PM CST /NOON MST/ THIS AFTERNOON FOR
NDZ009-017>020-031>035-040>046.
WIND CHILL WARNING UNTIL 1 PM CST THIS AFTERNOON FOR NDZ001>005-
010>013-021>023-025-036-037-047-048-050-051.
&&
$$
UPDATE...WAA
SHORT TERM...NH
LONG TERM...WAA
AVIATION...WAA
AREA FORECAST DISCUSSION
NWS BISMARCK ND
325 AM CST TUE JAN 28 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 325 AM CST TUE JAN 28 2014
FORECAST HIGHLIGHTS IN THE SHORT TERM PERIOD WILL BE WIND CHILL
HEADLINES THIS MORNING...THEN A WARMING TREND THIS AFTERNOON INTO
TONIGHT.
CURRENTLY...NORTHERLY FLOW ALOFT REMAINS OVER THE NORTHERN PLAINS
WITH SURFACE HIGH PRESSURE BUILDING INTO WESTERN NORTH DAKOTA. AN
AREA OF BKN-OVC CIGS AROUND 4-5K FEET AGL ALONG THE
MANITOBA/SASKATCHEWAN BORDER CONTINUES TO SLOWLY MOVE SOUTH WITH
THE MEAN FLOW. STILL SHOWING OBS UNDERNEATH THESE CLOUDS REPORTING
LIGHT SNOW WITH NO IMPACT TO VISIBILITIES. THESE CLOUDS APPEAR TO
BE ASSOCIATED WITH WAA ON THE BACKSIDE OF THE SFC RIDGE AND A
SUBTLE MID LEVEL IMPULSE. USED THE LATEST RAP 925-850MB RH
DEPICTION...WHICH SEEMS TO BEST CAPTURE THE CURRENT AERIAL
COVERAGE AND TIMING OF THESE CLOUDS. THUS INCREASED SKY COVER
NORTH AND EAST NOW - 18Z AND MENTIONED ISOLATED FLURRIES ACROSS MY
NORTHEAST WHERE/WHEN THE HR MODELS TRACK THESE CLOUDS.
RIDGE OF SFC HIGH PRESSURE REMAINS OVER WESTERN AND CENTRAL NORTH
DAKOTA THROUGH TODAY. AS MENTIONED ABOVE...WAA IS OCCURRING ON THE
BACKSIDE OF THE RIDGE AND WILL CONTINUE INTO THIS AFTERNOON. THUS
DESPITE A COLD START THIS MORNING WITH SUBZERO TEMPERATURES...WILL
SEE AFTERNOON TEMPERATURES CLIMB TO POSITIVE READINGS ALL
LOCATIONS.
STRONG EMBEDDED S/WV DROPS SOUTH ACROSS SOUTH CENTRAL CANADA
TONIGHT...WITH AN ASSOCIATED SFC LOW DEVELOPING ACROSS CENTRAL
SASKATCHEWAN IN THE EVENING MOVING TOWARDS LAKE WINNIPEG
OVERNIGHT. WAA RAMPS UP AS WE REMAIN IN THE WARM SECTOR OF THE LOW
THROUGH 12Z. A 10-15 MPH SOUTHWEST MIXING WIND WILL ALLOW
TEMPERATURES FROM THIS AFTERNOON TO REMAIN STEADY OR RISE TONIGHT
BE SEVERAL DEGREES.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 325 AM CST TUE JAN 28 2014
THE MAIN FEATURE IN THE EXTENDED PERIOD CONTINUES TO BE THE LARGE
COLD UPPER LOW OVER CENTRAL AND EASTERN CANADA. THIS WILL BRING A
STEADY STREAM OF WEAK IMPULSES/COLD FRONTS THROUGH THE NORTHERN
PLAINS. MOISTURE IS QUITE LIMITED AND THE MODELS HAVE DEPICTED DRY
WEATHER THROUGH THE EXTENDED. WHILE THIS APPEARS REASONABLE EACH
IMPULSE COULD BRING SOME TRACE AMOUNTS OF FLURRIES OR LIGHT SNOW.
RATHER THAN BROADBRUSH 15-20 POPS ACROSS THE REGION THROUGH THE
PERIOD LEFT THE EXTENDED DRY EXCEPT FOR A BRUSHING OF LIGHT SNOW
ACROSS THE SOUTHWEST ON WEDNESDAY AND WEDNESDAY NIGHT. THE
ACCUMULATING SNOWS SHOW REMAINS WEST AND SOUTH OF THE REGION THOUGH.
TEMPERATURES SHOULD REMAIN NEAR OR BELOW NORMAL FOR THIS TIME OF THE
YEAR. THIS WILL BE A BREEZY PERIOD WITH COLD THE COLD FRONTAL
PASSAGES. FOCUSED ON THURSDAY/THURSDAY NIGHT IN THE HAZARDOUS
WEATHER OUTLOOK FOR SOME CRITICAL WIND CHILL TEMPERATURES INTO THE
ADVISORY CATEGORY NORTH AND EAST. DID NOT SEE ANY TARGETS OF
OPPORTUNITY TO DEPART FROM THE ALLBLEND GUIDANCE TODAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 325 AM CST TUE JAN 28 2014
VFR CONDITIONS FORECAST THROUGH THE 12Z TAF PERIOD ALL TERMINALS.
AN AREA OF BKN-OVC 4-5K FT AGL CIGS WILL MOVE SLOWLY SOUTH FROM
SOUTH CENTRAL CANADA INTO NORTHERN AND EASTERN NORTH DAKOTA NOW
THROUGH 18Z. KMOT AND KJMS MAY SEE IN ISOLATED LIGHT SNOW
SHOWER...BUT SHOULD NOT IMPACT AVIATION.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
WIND CHILL ADVISORY UNTIL 1 PM CST /NOON MST/ THIS AFTERNOON FOR
NDZ009-017>020-031>035-040>046.
WIND CHILL WARNING UNTIL 1 PM CST THIS AFTERNOON FOR NDZ001>005-
010>013-021>023-025-036-037-047-048-050-051.
&&
$$
SHORT TERM...NH
LONG TERM...WAA
AVIATION...NH
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1009 AM EST TUE JAN 28 2014
.SYNOPSIS...
A STRONG ARCTIC COLD FRONT WILL MOVE SOUTH OF OUR AREA TODAY AS
WAVES OF LOW PRESSURE TRACK NORTHEAST ALONG THE FRONT. WINTRY
PRECIPITATION WILL FALL FROM THE GULF COAST TO EASTERN NORTH
CAROLINA TODAY AND INTO WEDNESDAY. COLD AND DRY HIGH PRESSURE WILL
THEN MOVE INTO THE REGION LATE WEDNESDAY AND REMAIN IN PLACE THRU
THE END OF THE WORK WEEK. ANOTHER COLD FRONT IS EXPECTED TO APPROACH
THE AREA EARLY SUNDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
930 AM UPDATE...A FEW LIGHT SNOW ACCUM REPORTS HAVE ALREADY BEEN
RECEIVED IN THE MTNS WHERE WEAK ISENTROPIC UPGLIDE AND SWLY UPSLOPE
FLOW ARE ONGOING AND ENHANCING ANY LIFT FROM CHANNELED VORT EXITING
THE TROUGH. RATES ARE EVIDENTLY A LITTLE HIGHER OVER EAST TN...WHERE
DPVA AND FRONTOGENESIS ARE A BIT STRONGER ATTM. NEW 12Z NAM AND
LATEST RAP SUGGEST THESE FEATURES ADVECT EAST THIS MRNG. THESE
MODELS SHOW DECENT AGREEMENT IN DEVELOPING FGEN/OMEGA BAND ACRS THE
NRN UPSTATE/UPPER SAVANNAH VALLEY THIS AFTN...SUGGESTING PRECIP MAY
RAMP UP A BIT FASTER THERE THAN ANTICIPATED. REVISED POPS TO REFLECT
THIS AND SHARPER EDGES TO THE PIEDMONT SNOW EARLY IN THE EVENT.
REVISED QPF BASED ON A BLEND OF PREVIOUS FCST AND NEW
NAM/RAP...WHICH REALLY ARE IN LINE WITH MOST OTHER QPF GUIDANCE THRU
EVENING IN TERMS OF TOTALS. NEW STORM TOTALS SUGGEST WARNING
CRITERIA WILL NOW BE MET IN YORK CO...THUS ADDED THEM TO THE
WARNING. THE SAME GUID BLEND SUPPORTS A LITTLE HIGHER TOTALS IN THE
SW NC MTNS WITH MORE PRECIP FALLING EARLY ON AS THE FORCING
TRANSLATES ACRS THERE. PREVIOUS MTN ZONES IN THE ADVISORY STILL FALL
IN ADVY RANGE...BUT NOW AVERAGE ACCUMS ACRS HAYWOOD/TRANSYLVANIA
MEET ADVY CRITERIA. THUS THEY WERE ADDED TO THE ADVY.
WIND CHILL ADVY ACRS THE NRN MTNS WILL STAND AS-IS WITH SEVERAL
NEARBY OBS SITES REPORTING WIND CHILLS IN 0 TO -5 RANGE...THESE
BEING AT LOWER ELEVATIONS.
AT 230 AM EST TUESDAY...A BROAD UPPER TROUGH WILL EXTEND FROM THE
ROCKIES TO THE WESTERN ATLANTIC TODAY AND TONIGHT. SEVERAL
PROGRESSIVELY STRONGER CHANNELED IMPULSES WILL ROUND THE BASED OF
THE TROUGH EARLY TODAY.
LOW LEVEL MOISTURE OVER OUR AREA IS EXPECTED TO RAPIDLY INCREASE...
WITH PRECIPITATION BREAKING OUT FIRST IN THE MOUNTAINS IN RESPONSE
TO THE SERIES OF MID LEVEL IMPULSES. MODEL SOUNDINGS SUPPORT
SNOW...BUT ACCUMULATIONS WILL BE LIMITED BY ONLY WEAK ORTHOGONAL
FLOW INTO THE HIGHER TERRAIN.
THE UPPER TROUGH WILL AMPLIFY DURING THE DAY...AS A STRONG SHORTWAVE
MOVES INTO ITS BASE. MEANWHILE...A SURFACE LOW WILL FORM ON A SLOW
MOVING COLD FRONT OFF THE COAST. ALTHOUGH THE BEST LIFT ASSOCIATED
WITH THE SURFACE BOUNDARY WILL TO OUR SOUTHEAST...WIDESPREAD LIGHT
PRECIPITATION IS EXPECTED TO DEVELOP ACROSS THE PIEDMONT AND
FOOTHILLS LATE THIS MORNING. MODEL SOUNDINGS SUPPORT AN ALL SNOW
SCENARIO. HIGH TEMPERATURES TODAY WILL RANGE FROM UPPER TEENS IN THE
NORTHERN NC MOUNTAINS.
PRECIPITATION WILL BEGIN TO TAPER OFF FROM THE WEST LATE THIS
EVENING AS THE COASTAL WAVE MOVES OFF TO THE NE...AND DRIER AIR
WORKS INTO THE AREA FROM THE NW...LEAVING JUST LIGHT SNOW IN THE FAR
SE BY DAYBREAK. LOW TEMPERATURES TONIGHT WILL RUN AROUND 12 DEGREES
BELOW NORMAL...ALTHOUGH RECENT GUIDANCE HAS WARMED CONSIDERABLY IN
THE NC MOUNTAINS. FOR NOW...JUST A NOD IN THAT DIRECTION HAS BEEN
MADE...WARMING THE NC MOUNTAINS SLIGHTLY. IF TEMPERATURES REMAIN
COLD...WIND CHILL COULD BE A PROBLEM IN THE NC MOUNTAINS LATE
TONIGHT...BUT THE DECISION ON AN ADVISORY WILL LEFT UNTIL AFTER A
CURRENT WIND CHILL ADVISORY THERE EXPIRES.
QPF WILL BE LIMITED THIS FAR NORTH OF THE BETTER LIFT NEAR THE
FRONT...BUT ENOUGH FOR WARNING CRITERIA SNOW IN OUR FAR SE PIEDMONT
ZONES FROM ELBERT CO GA TO UNION CO NC. ADVISORY CRITERIA SNOW IS
EXPECTED IN THE REST OF OUR FOOTHILLS AND PIEDMONT...AND PORTIONS OF
THE SW NC MOUNTAINS.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 230 AM EST TUESDAY...THE SHORT RANGE PERIOD IS TRANQUIL BY
COMPARISON...ALTHOUGH RELATIVELY COLD. THE TREND IN THE LATEST MODEL
GUIDANCE IS TO MOVE ALL THE PRECIP WELL TO OUR EAST BY 12Z
WEDNESDAY...SO THE FORECAST REFLECTS THAT DEVELOPMENT. WE SHOULD
CLEAR OUT FROM THE WEST THROUGHOUT THE DAY ALTHOUGH THE HIGH
PRESSURE CENTER WILL REMAIN TO OUR WEST. TEMPS WILL REBOUND A FEW
DEGREES SIMPLY BECAUSE PRECIP WILL NOT BE FALLING...BUT IT WILL
STILL BE ABOUT 15 DEGREES BELOW NORMAL. A TRAILING SHORT WAVE WILL
MOVE OVERHEAD LATE IN THE DAY WITH LITTLE IMPACT...AS THERE WILL BE
NO MOISTURE TO WORK WITH. SURFACE HIGH PRESSURE WILL MOVE OVERHEAD
WEDNESDAY NIGHT AS THE UPPER FLOW FLATTENS OUT IN THE WAKE OF THE
SHORT WAVE. LITTLE CHANGE WAS MADE TO THE TEMPS. THE FLOW BECOMES
NEARLY ZONAL ON THURSDAY AND THURSDAY NIGHT WHICH SHOULD HOLD
SURFACE HIGH PRESSURE ALONG THE SOUTHEAST COAST THROUGH THE END OF
THE PERIOD. TEMPS SHOULD MODERATE A BIT THURSDAY AND THURSDAY
NIGHT...ALTHO STILL 10 DEGREES BELOW NORMAL.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 230 AM TUESDAY...THE MEDIUM RANGE PICKS UP AT 12Z ON FRIDAY WITH
THE BROAD UPPER TROF WELL TO OUR NORTH AND A RELATIVELY ZONAL
PATTERN OVER THE FCST AREA. AN UPPER SHORTWAVE IS PROJECTED TO MOVE
ACROSS THE CWFA ON SUN WITH A ZONAL PATTERN SETTING BACK UP FOR THE
REMAINDER OF THE PERIOD. BY EARLY NEXT WEEK...THE LONG RANGE MODELS
BEGIN INCREASING HEIGHTS AS THEY AMPLIFY AN UPPER RIDGE OVER THE
GULF OF MEXICO AND CARIBBEAN.
AT THE SFC...THE WEAK AND DIFFUSE COLD FRONT THAT APPROACHES FROM
THE NW ON FRI STILL LOOKS LIKE IT WILL STALL OUT JUST TO OUR NORTH
AS WEAK LOW LVL SLY FLOW PERSISTS OVER THE CWFA. ANOTHER LOW IS
EXPECTED TO DEVELOP OVER THE CENTRAL MISS RIVER VALLEY ON SAT AND
TRACK NE TOWARDS NEW ENGLAND. THE LONG RANGE MODELS HAVE THE LOWS
ASSOCIATED COLD FRONT MOVING INTO THE CAROLINAS EARLY SUN AND THEN
OFFSHORE BY EARLY MON. BEYOND THIS POINT...THE MODEL SOLUTIONS
DIVERGE SIGNIFICANTLY WITH THE LATEST RUN OF THE ECWMF SPINNING UP
ANOTHER LOW OVER THE FCST AREA ON MON AND TRACKING NE AND OFFSHORE
BY MON EVENING...WHILE THE GFS SPREADS DRY HIGH PRESSURE OVER THE
CWFA BY EARLY MON AND MAINTAINS IT INTO TUES. FOR THE SENSIBLE
FCST...I RAMP POPS UP MORE SLOWLY TO SLIGHT CHANCE BY FRI EVENING
AND THEN SOLID CHANCE ON SAT AND SUN. I BRING POPS BACK UP TO SOLID
CHANCE BY DAY 7 ON TUES TO ACCOUNT FOR WHAT APPEARS TO BE ANOTHER
LOW THAT DEVELOPS TO OUR SW. TEMPS SHOULD STEADILY CLIMB THRU THE
WEEKEND WITH HIGHS REACHING THE LOW 60S OVER THE SC UPSTATE. THEY
WILL LIKELY DIP AGAIN EARLY NEXT WEEK AFTER THE FROPA ON SUN.
&&
.AVIATION /15Z TUESDAY THROUGH SATURDAY/...
AT KCLT /15Z UPDATE/...LIGHT SNOW WILL BEGIN AS FLURRIES AROUND
MIDDAY AS FRONTOGENETIC FORCING BEGINS TO INCREASE IN
MIDLEVELS...WITH SNOWFALL RATES MAXIMIZING MID AFTN AS SAID FORCING
PEAKS. GUIDANCE BRINGS MVFR TO IFR CIG RESTRICTION WITH -SN LATE
AFTN UNTIL AROUND SUNSET. SNOWFALL TOTALS ARE EXPECTED TO BE AROUND
2 INCHES. IMPROVEMENT TO VFR OCCURS AFTER MIDNIGHT AS DRIER AIR
MOVES IN BEHIND A DEPARTING COASTAL LOW. WINDS WILL BACK FROM NE TO
N BY EARLY AFTN...BUT WILL WEAKEN AS THE PRESSURE GRADIENT RELAXES
THEREAFTER.
ELSEWHERE...SNOW CURRENTLY OVER THE MTNS WILL SPREAD TO FOOTHILL
SITES BY MIDDAY. PERIODIC IFR RESTRICTIONS LIKELY. RESTRICTIONS
APPEAR MID-LATE AFTERNOON AS SNOWFALL RATES INCREASE...WHEN MVFR
CIGS AFFECT ALL SITES BUT KAND. BY EARLY EVENING AN IFR CIG SETS UP
AT KAND. VSBY RESTRICTIONS WILL OCCUR ABOUT THE SAME TIME...WITH
MVFR TO BRIEF IFR. IMPROVEMENTS TO VFR OCCUR LATE THIS EVENING AS
THE COASTAL LOW RESPONSIBLE FOR THE NOW MOVES OFF TO THE NORTHEAST.
WINDS WILL GRADUALLY BACK FORM NE TO N...WEAKENING AS THE PRESSURE
GRADIENT RELAXES.
OUTLOOK...VFR UNDER COLD HIGH PRESSURE LASTING THROUGH THU. LIGHT
PRECIPITATION AND SOME RESTRICTIONS MAY RETURN FRI-SAT AS LOW
PRESSURE MOVES WEST OF THE AREA.
CONFIDENCE TABLE...
15-21Z 21-03Z 03-09Z 09-15Z
KCLT HIGH 94% HIGH 88% HIGH 93% HIGH 100%
KGSP HIGH 88% HIGH 98% HIGH 95% HIGH 100%
KAVL HIGH 90% HIGH 91% HIGH 86% HIGH 100%
KHKY HIGH 86% HIGH 100% HIGH 98% HIGH 100%
KGMU HIGH 93% HIGH 97% HIGH 93% HIGH 100%
KAND HIGH 86% HIGH 94% HIGH 92% HIGH 87%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...WINTER WEATHER ADVISORY UNTIL 9 AM EST WEDNESDAY FOR GAZ010-
017-018-026-028.
WINTER STORM WARNING UNTIL 9 AM EST WEDNESDAY FOR GAZ029.
NC...WINTER WEATHER ADVISORY UNTIL 9 AM EST WEDNESDAY FOR
NCZ035>037-056-057-068>072-502-504-506-508-510.
WINTER WEATHER ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR NCZ051-
052-058-059-062>064.
WIND CHILL ADVISORY UNTIL NOON EST TODAY FOR NCZ033-049-050.
WINTER STORM WARNING UNTIL 9 AM EST WEDNESDAY FOR NCZ082.
SC...WINTER WEATHER ADVISORY UNTIL 9 AM EST WEDNESDAY FOR
SCZ001>008-010.
WINTER STORM WARNING UNTIL 9 AM EST WEDNESDAY FOR SCZ009-
011>014-019.
&&
$$
SYNOPSIS...JPT
NEAR TERM...JAT/WIMBERLEY
SHORT TERM...PM
LONG TERM...JPT
AVIATION...JAT/WIMBERLEY
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
824 PM MST WED JAN 29 2014
.UPDATE...
ISSUED AT 815 PM MST WED JAN 29 2014
03Z SFC ANALYSIS PLACES LOW CENTER OVER WCNTRL SD WITH SNOW
FALLING FROM THE BLKHLS INTO FAR NWRN SD. K2WX HAS REPORTED
MEASURED 0.07 AND AREA WEBCAMS SHOW LITTLE FALLING ELSEWHERE ON THE
PLAINS. LOTS OF VIRGA ON RADAR AND ITS TAKING SOME TIME TO
SATURATE THE LOW LEVELS BELOW 600MB (SEE 00Z KUNR SOUNDING). EARLY
00Z MODEL RUNS STILL SHOWING THE BEST ACCUMULATIONS ACRS THE
BLKHLS AS WELL AS FAR NWRN SD THROUGH EARLY THU MRNG...AND THOSE
WINTER WX ADVISORIES LOOK GOOD. STILL SOME QUESTION AS TO HOW MUCH
SNOW WILL FALL ACRS NERN WY...BUT SOME ADVISORY AMOUNTS MAY FALL
NEAR THE MT BORDER. CURRENT FCST IS IN QUITE GOOD SHAPE AND WILL
ONLY MAKE MINOR MODIFICATIONS TO THE GRIDDED FCST AT THIS TIME
BASED ON CURRENT CONDITIONS.
UPDATE ISSUED AT 641 PM MST WED JAN 29 2014
HIGHER RES MODELS FROM THIS AFTERNOON AND THE 00Z RAP HAVE BEEN
SHOWING MORE SNOWFALL (3-6 INCHES) FOR THE HIGHER TERRAIN OF THE
CNTRL/SRN HILLS TONIGHT...PRIMARILY WEST OF MYSTIC...HILL
CITY...AND CUSTER. THIS IS ALSO BEING SUPPORTED BY RECENT HIGHER
RADAR REFLECTIVITIES IN THE SRN HILLS. THUS...HAVE EXPANDED THE
WINTER WX ADVISORIES TO INCLUDE THE CNTRL/SRN BLKHLS. NOTHING ELSE
CHANGED AT THIS TIME.
&&
.SHORT TERM...THIS EVENING THROUGH THURSDAY NIGHT
ISSUED AT 124 PM MST WED JAN 29 2014
20Z SURFACE ANALYSIS HAD COLD FRONT FROM SOUTHERN AB INTO
NORTHEAST MT/NORTHERN ND. WATER VAPOR SHOWED FLAT UPPER RIDGE
OVER THE CWA. UPPER LOW/SHORTWAVE OVER CENTRAL MB MAIN INTEREST
FOR TONIGHT...AND THEN UPPER TROUGH/SERIES OF SHORTWAVES MOVING
FROM THE WEST COAST ACROSS THE ROCKIES INTO THE CENTRAL PLAINS FOR
LATE THURSDAY/THURSDAY NIGHT.
TONIGHT...UPPER LOW/SHORTWAVE SHIFTS INTO CENTRAL ON...SPINNING
SHORTWAVE ENERGY/SHEAR AXIS SOUTH INTO THE CWA. SURFACE LOW PRESSURE
WILL DEVELOP ALONG CURRENT COLD FRONT IN SOUTHERN AB...MOVING
THROUGH CWA TONIGHT...REACHING NORTHWEST IA 12Z THURSDAY. SYNOPTIC
LIFT WILL BE PROVIDED BY DEPARTING 110KT JET STREAK/RIGHT ENTRANCE
REGION...AND APPROACHING 150KT JET STREAK ACROSS THE ROCKIES. VERY
TIGHT LOW LEVEL THERMAL GRADIENT DEVELOPS BEHIND COLD FRONT AND
SUBSEQUENT STRONG FRONTOGENESIS. FEATURES SHOULD SYNC UP OVER
SOUTHEAST MT INTO NORTHWEST SD LEADING TO SEVERAL INCHES OF SNOW BY
THURSDAY MORNING...LIKELY FORMING A HEAVIER BAND OF SNOW SOMEWHERE
FROM FAR NORTHEAST WY INTO NORTHWEST SD. BEHIND COLD FRONT AS HIGH
PRESSURE SETTLES IN...WEAK NORTHEAST UPSLOPE BOUNDARY LAYER FLOW
DEVELOPS ON THE SD PLAINS. FLOW WILL BE MORE NORTHERLY OVER WESTERN
HALF OF CWA WITH FROUDE NUMBERS ABOVE 1 FOR 6-9 HOURS TONIGHT WITH
SATURATED LOW LEVELS. EXPECT UPSLOPE ENHANCED SNOWS OVER THE
NORTHERN BLACK HILLS. WILL HOIST APPROPRIATE HEADLINES WITH
AFTERNOON PACKAGE. TEMPERATURES WILL RETURN TO QUITE CHILLY READINGS
AS COLD AIR OOZES INTO THE AREA OVERNIGHT.
THURSDAY...BETTER SNOWS PUSH EAST OF THE CWA IN THE MORNING AS HIGH
PRESSURE POKES INTO THE DAKOTAS. NEXT UPSTREAM WAVE ALREADY
IMPINGING ON THE ROCKIES WITH LOW FORMING OVER WESTERN WY. LIFT
AHEAD OF SYSTEM WILL LIKELY INCREASE -SN COVERAGE OVER SOUTHWEST
THIRD OF CWA LATE IN THE DAY. TEMPERATURES WILL BE MUCH COLDER THAN
TODAY.
THURSDAY NIGHT...BEST LIFT SHIFTS ACROSS EASTERN WY INTO FAR
SOUTHWEST SD. NOTABLE 850-700MB FRONTOGENESIS...SO HAVE INCREASED
POPS TO ACCOUNT. LATER SHIFTS WILL NEED TO TAKE A CLOSER LOOK AT
WHETHER HEADLINES WILL BE NEEDED.
&&
.LONG TERM...FRIDAY THROUGH WEDNESDAY
ISSUED AT 124 PM MST WED JAN 29 2014
ACTIVE WEST-NORTHWEST FLOW ALOFT WILL CONTINUE TO BRING SOME
UNSETTLED WEATHER OVER SOUTHERN SD FRIDAY...WHICH WILL CLEAR OUT
THROUGH THE DAY. THE ARCTIC BOUNDARY WILL GENERALLY REMAIN TO THE
SOUTH AND WEST OF THE FORECAST AREA THROUGH THE WEEKEND AND INTO
NEXT WEEK...KEEPING TEMPERATURES BELOW AVERAGE. DRY CONDITIONS ARE
EXPECTED THIS WEEKEND INTO THE EARLY WORK WEEK AS HIGH PRESSURE
SLIDES THROUGH THE NORTHERN PLAINS. CHANCES FOR LIGHT SNOW COULD
RETURN OVER WESTERN AND SOUTHERN PORTIONS OF THE CWA TOWARD THE
MIDDLE OF THE WEEK AS ARCTIC AIR MAKES ANOTHER PUSH INTO THE
REGION.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 410 PM MST WED JAN 29 2014
AN UPPER LEVEL DISTURBANCE WILL QUICKLY SLIDE THROUGH THE AREA
TONIGHT AND BRING SNOW TO MUCH OF THE AREA...ALONG WITH MVFR/IFR
CONDITIONS. THE BEST CHANCES WILL BE TONIGHT ACROSS NW SD AND
PORTIONS OF NE WY. MVFR/IFR CONDITIONS ARE EXPECTED TO CONTINUE
THROUGH MUCH OF THE DAY THURSDAY AS SNOW SLOWLY SLIDES SOUTHWARD.
&&
.UNR WATCHES/WARNINGS/ADVISORIES...
SD...WINTER WEATHER ADVISORY UNTIL NOON MST THURSDAY FOR SDZ024.
WINTER WEATHER ADVISORY UNTIL 7 AM MST THURSDAY FOR SDZ001-002-
012-013-025-028-029.
WY...WINTER WEATHER ADVISORY UNTIL NOON MST THURSDAY FOR WYZ057.
WINTER WEATHER ADVISORY UNTIL 7 AM MST THURSDAY FOR WYZ054-056-
071.
&&
$$
UPDATE...JOHNSON
SHORT TERM...HELGESON
LONG TERM...13
AVIATION...JOHNSON
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
648 PM MST WED JAN 29 2014
.UPDATE...
ISSUED AT 641 PM MST WED JAN 29 2014
HIGHER RES MODELS FROM THIS AFTERNOON AND THE 00Z RAP HAVE BEEN
SHOWING MORE SNOWFALL (3-6 INCHES) FOR THE HIGHER TERRAIN OF THE
CNTRL/SRN HILLS TONIGHT...PRIMARILY WEST OF MYSTIC...HILL
CITY...AND CUSTER. THIS IS ALSO BEING SUPPORTED BY RECENT HIGHER
RADAR REFLECTIVITIES IN THE SRN HILLS. THUS...HAVE EXPANDED THE
WINTER WX ADVISORIES TO INCLUDE THE CNTRL/SRN BLKHLS. NOTHING ELSE
CHANGED AT THIS TIME.
&&
.SHORT TERM...THIS EVENING THROUGH THURSDAY NIGHT
ISSUED AT 124 PM MST WED JAN 29 2014
20Z SURFACE ANALYSIS HAD COLD FRONT FROM SOUTHERN AB INTO
NORTHEAST MT/NORTHERN ND. WATER VAPOR SHOWED FLAT UPPER RIDGE
OVER THE CWA. UPPER LOW/SHORTWAVE OVER CENTRAL MB MAIN INTEREST
FOR TONIGHT...AND THEN UPPER TROUGH/SERIES OF SHORTWAVES MOVING
FROM THE WEST COAST ACROSS THE ROCKIES INTO THE CENTRAL PLAINS FOR
LATE THURSDAY/THURSDAY NIGHT.
TONIGHT...UPPER LOW/SHORTWAVE SHIFTS INTO CENTRAL ON...SPINNING
SHORTWAVE ENERGY/SHEAR AXIS SOUTH INTO THE CWA. SURFACE LOW PRESSURE
WILL DEVELOP ALONG CURRENT COLD FRONT IN SOUTHERN AB...MOVING
THROUGH CWA TONIGHT...REACHING NORTHWEST IA 12Z THURSDAY. SYNOPTIC
LIFT WILL BE PROVIDED BY DEPARTING 110KT JET STREAK/RIGHT ENTRANCE
REGION...AND APPROACHING 150KT JET STREAK ACROSS THE ROCKIES. VERY
TIGHT LOW LEVEL THERMAL GRADIENT DEVELOPS BEHIND COLD FRONT AND
SUBSEQUENT STRONG FRONTOGENESIS. FEATURES SHOULD SYNC UP OVER
SOUTHEAST MT INTO NORTHWEST SD LEADING TO SEVERAL INCHES OF SNOW BY
THURSDAY MORNING...LIKELY FORMING A HEAVIER BAND OF SNOW SOMEWHERE
FROM FAR NORTHEAST WY INTO NORTHWEST SD. BEHIND COLD FRONT AS HIGH
PRESSURE SETTLES IN...WEAK NORTHEAST UPSLOPE BOUNDARY LAYER FLOW
DEVELOPS ON THE SD PLAINS. FLOW WILL BE MORE NORTHERLY OVER WESTERN
HALF OF CWA WITH FROUDE NUMBERS ABOVE 1 FOR 6-9 HOURS TONIGHT WITH
SATURATED LOW LEVELS. EXPECT UPSLOPE ENHANCED SNOWS OVER THE
NORTHERN BLACK HILLS. WILL HOIST APPROPRIATE HEADLINES WITH
AFTERNOON PACKAGE. TEMPERATURES WILL RETURN TO QUITE CHILLY READINGS
AS COLD AIR OOZES INTO THE AREA OVERNIGHT.
THURSDAY...BETTER SNOWS PUSH EAST OF THE CWA IN THE MORNING AS HIGH
PRESSURE POKES INTO THE DAKOTAS. NEXT UPSTREAM WAVE ALREADY
IMPINGING ON THE ROCKIES WITH LOW FORMING OVER WESTERN WY. LIFT
AHEAD OF SYSTEM WILL LIKELY INCREASE -SN COVERAGE OVER SOUTHWEST
THIRD OF CWA LATE IN THE DAY. TEMPERATURES WILL BE MUCH COLDER THAN
TODAY.
THURSDAY NIGHT...BEST LIFT SHIFTS ACROSS EASTERN WY INTO FAR
SOUTHWEST SD. NOTABLE 850-700MB FRONTOGENESIS...SO HAVE INCREASED
POPS TO ACCOUNT. LATER SHIFTS WILL NEED TO TAKE A CLOSER LOOK AT
WHETHER HEADLINES WILL BE NEEDED.
&&
.LONG TERM...FRIDAY THROUGH WEDNESDAY
ISSUED AT 124 PM MST WED JAN 29 2014
ACTIVE WEST-NORTHWEST FLOW ALOFT WILL CONTINUE TO BRING SOME
UNSETTLED WEATHER OVER SOUTHERN SD FRIDAY...WHICH WILL CLEAR OUT
THROUGH THE DAY. THE ARCTIC BOUNDARY WILL GENERALLY REMAIN TO THE
SOUTH AND WEST OF THE FORECAST AREA THROUGH THE WEEKEND AND INTO
NEXT WEEK...KEEPING TEMPERATURES BELOW AVERAGE. DRY CONDITIONS ARE
EXPECTED THIS WEEKEND INTO THE EARLY WORK WEEK AS HIGH PRESSURE
SLIDES THROUGH THE NORTHERN PLAINS. CHANCES FOR LIGHT SNOW COULD
RETURN OVER WESTERN AND SOUTHERN PORTIONS OF THE CWA TOWARD THE
MIDDLE OF THE WEEK AS ARCTIC AIR MAKES ANOTHER PUSH INTO THE
REGION.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 410 PM MST WED JAN 29 2014
AN UPPER LEVEL DISTURBANCE WILL QUICKLY SLIDE THROUGH THE AREA
TONIGHT AND BRING SNOW TO MUCH OF THE AREA...ALONG WITH MVFR/IFR
CONDITIONS. THE BEST CHANCES WILL BE TONIGHT ACROSS NW SD AND
PORTIONS OF NE WY. MVFR/IFR CONDITIONS ARE EXPECTED TO CONTINUE
THROUGH MUCH OF THE DAY THURSDAY AS SNOW SLOWLY SLIDES SOUTHWARD.
&&
.UNR WATCHES/WARNINGS/ADVISORIES...
SD...WINTER WEATHER ADVISORY UNTIL NOON MST THURSDAY FOR SDZ024.
WINTER WEATHER ADVISORY UNTIL 7 AM MST THURSDAY FOR SDZ001-002-
012-013-025-028-029.
WY...WINTER WEATHER ADVISORY UNTIL NOON MST THURSDAY FOR WYZ057.
WINTER WEATHER ADVISORY UNTIL 7 AM MST THURSDAY FOR WYZ054-056-
071.
&&
$$
UPDATE...JOHNSON
SHORT TERM...HELGESON
LONG TERM...13
AVIATION...JOHNSON
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
1012 PM MST MON JAN 27 2014
.UPDATE...
ISSUED AT 513 PM MST MON JAN 27 2014
RADAR ECHOES HAVE BEEN INCREASING WITHIN THE LAST HOUR ACROSS THE
NRN BLKHLS AND THE PLAINS JUST TO THE NORTH/EAST OF THE BLKHLS.
00Z KUNR SOUNDING IS SHOWING A FAIRLY MOIST PROFILE UP TO ABOUT
650MB SO HAVE ADDED SMALL CHANCES OF LIGHT SNOW TO THE FCST FOR
THE REST OF THE NIGHT. THE OTHER FCST CHANGE WAS TO ISSUE A WIND
CHILL ADVISORY FOR FAR NWRN SD...WHERE THERE SHOULD BE JUST ENOUGH
WIND WITH THE FALLING TEMPS TO PUSH WIND CHILLS DOWN TO -30F IN
THAT AREA.
&&
.SHORT TERM...THIS EVENING THROUGH TUESDAY NIGHT
ISSUED AT 312 PM MST MON JAN 27 2014
LATEST SATELLITE IMAGES...SURFACE OBS...AND WEBCAMS SHOW A BAND
OF MIDLEVEL CLOUDS STRETCHING FROM ERN MT THROUGH NERN WY INTO
SWRN SD. THIS BAND WAS MOVING SOUTHWARD IN ASSOCIATION WITH THE
LARGE UPPER-LEVEL TROUGH MOVING OVER THE NORTHERN PLAINS AS WELL
AS WITH THE UPPER-LEVEL CYCLONICALLY CURVED JET THAT WAS OVER THE
INTERMOUNTAIN WEST. THESE CLOUDS WILL AFFECT LOW TEMPERATURES OVER
THE SWRN CWA OVERNIGHT...THUS HAVE NOT GONE TOO LOW WITH MIN TEMPS
THERE. OTHERWISE...SURFACE HIGH PRESSURE WILL MOVE OVER THE
DAKOTAS TONIGHT WITH GENERALLY LIGHT WINDS. MIDLEVEL HEIGHTS WILL
BE RISING LATE TNGT AS THE TROUGH AXIS MOVES SOUTHEAST OF THE CWA.
SOME OF THE HI-RES WRF MODELS AS WELL AS THE RAP MODEL INDICATE
LIGHT SNOW OVER THE HIGHER BLKHLS OVERNIGHT...BUT THIS IS NOT
WARRANTED GIVEN THE HIGH CLOUD BASES AS WELL AS PWAT NEAR 0.05
INCHES.
MIDLEVEL HEIGHTS WILL CONTINUE TO RISE ON TUESDAY AS SHORT-WAVE
RIDGING ENSUES OVER THE NRN HIGH PLAINS. RETURN SOUTHWEST FLOW WILL
DEVELOP OVER NERN WY IN RESPONSE TO LOW-LEVEL WARM ADVECTION AND
PRESSURE FALLS OVER THE NRN PLAINS. SUNNY SKIES ARE EXPECTED.
ON TUESDAY NIGHT THE SHORT-WAVE RIDGE WILL MOVE OVER THE CWA WITH
INCREASING HIGH-LEVEL CLOUDS. SOUTHWEST WINDS WILL DEVELOP ACROSS
ALL OF THE CWA. STRONGER WINDS OF 20-30 MPH ARE LIKELY OVER PARTS OF
NERN WY AND THE BLKHLS AS THE SURFACE PRESSURE GRADIENT TIGHTENS IN
THAT AREA...ROUGHLY A 5-MB DIFFERENCE FROM KECS TO KSPF. WIND SPEEDS
HAVE BEEN INCREASED...BUT MAY NEED TO DO SO EVEN MORE IN LATER
SHIFTS. IT ALSO WILL BE RELATIVELY MILD WITH PARTS OF THE NERN
FOOTHILLS STAYING IN THE 20S MOST OF THE NIGHT.
&&
.LONG TERM...WEDNESDAY THROUGH MONDAY
ISSUED AT 312 PM MST MON JAN 27 2014
ACTIVE WEST-NORTHWEST FLOW ALOFT WILL BRING SOME UNSETTLED WEATHER
TO THE AREA FROM LATER WEDNESDAY THROUGH FRIDAY...ESPECIALLY OVER
WESTERN AND SOUTHERN PORTIONS OF THE CWA. ARCTIC BOUNDARY WILL SHIFT
EAST OF THE REGION FOR A BRIEF TIME ON WEDNESDAY...ALLOWING FOR MILD
TEMPERATURES ACROSS THE FORECAST AREA. THE BOUNDARY WILL SLIP BACK
TO THE SOUTH AND WEST WEDNESDAY NIGHT AND THURSDAY AS AN UPPER LEVEL
SHORTWAVE CROSSES THE AREA. THIS WILL BRING A GOOD CHANCE FOR SNOW
TO MUCH OF THE AREA WEDNESDAY NIGHT. POTENTIAL ACCUMULATIONS LOOK TO
BE ON THE LIGHTER SIDE AT THIS POINT...UP TO A COUPLE OF INCHES OR
SO...WITH THE BETTER CHANCES OVER NORTHEASTERN WY...THE BLACK
HILLS...AND SOUTHWESTERN SD. ADDITIONAL UPPER LEVEL ENERGY WILL
INTERACT WITH THE STALLED FRONTAL BOUNDARY SOUTH AND WEST OF THE
CWA. THIS WILL BRING CONTINUED CHANCES FOR SNOW....THOUGH ADDITIONAL
ACCUMULATIONS ALSO LOOK TO BE LIGHT. TEMPS WILL BE BELOW AVERAGE
ACROSS THE AREA FROM THURSDAY THROUGH THE WEEKEND...WITH HIGHS
MOSTLY IN THE 20S AND LOWER 30S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1009 PM MST MON JAN 27 2014
MVFR CIGS IN -SN AROUND THE BLKHLS AND ADJACENT PLAINS WILL
DISSPATE AFTER MIDNIGHT...WITH VFR CONDITIONS THEN EXPECTED ACRS
THE ENTIRE AREA THROUGH TUESDAY.
&&
.UNR WATCHES/WARNINGS/ADVISORIES...
SD...WIND CHILL ADVISORY UNTIL 11 AM MST TUESDAY FOR SDZ001-002-013-
014.
WY...NONE.
&&
$$
UPDATE...JOHNSON
SHORT TERM...BUNKERS
LONG TERM...13
AVIATION...JOHNSON
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
929 PM CST WED JAN 29 2014
.UPDATE...
SATELLITE IMAGERY SHOWS STRATUS WAS JUST SOUTH OF SOUTH CENTRAL
TEXAS AND MOVING NORTH THIS EVENING. EVENING NAM AND RUC RUNS
SHOW LOWER LEVEL MOISTURE AND ASSOCIATED CLOUDS APPROACHING I-35
LATE TONIGHT. THIS SEEMS REASONABLE DUE DEVELOPING SOUTHERLY FLOW.
HAVE BOOSTED CLOUD COVER TO PARTLY TO MOSTLY CLOUDY ALONG AND EAST
OF I-35 LATE TONIGHT INTO EARLY MORNING THURSDAY. DAYTIME MIXING
WILL ERODE THE CLOUDS LATE MORNING INTO AFTERNOON. TEMPERATURES
WILL CONTINUE TO DROP MOST OF THE NIGHT REACHING EXPECTED LOWS AND
THEN RISE TOWARD MORNING AS LOWER LEVEL MOISTURE INCREASES. HAVE
ALSO BOOSTED DEWPOINTS TOWARD MORNING. REMAINDER OF SOUTH CENTRAL
TEXAS FORECAST IS ON TRACK.
&&
.PREV DISCUSSION... /ISSUED 536 PM CST WED JAN 29 2014/
AVIATION...
VFR CONDITIONS TO PREVAIL THROUGH FORECAST PERIOD AS HIGH PRESSURE
RIDGE SOUTHEAST OF AREA WEAKENS AND LOW PRESSURE DEEPENS TO THE
NORTHWEST. RESULTANT PRIMARILY SOUTHERLY WINDS OF 5 TO 10 KTS
TONIGHT INCREASING TO 15 TO 20 KNOTS AFTER 15Z THU AND CONTG
THROUGH THU AFTERNOON. SOME SCT CLDS OF 4-5K THU MRNG OVR I-35
TAFS EXPECTED TO ERODE BY THU AFTERNOON.
PREV DISCUSSION... /ISSUED 325 PM CST WED JAN 29 2014/
SHORT TERM (TONIGHT THROUGH THURSDAY NIGHT)...
EXPECT MOSTLY SUNNY SKIES FOR THE REST OF THIS AFTERNOON. MAY SEE
A GROUP OF MID TO UPPER LEVEL CLOUDS MOVING IN FROM THE SOUTHWEST
WITHIN THE NEXT FEW HOURS...HOWEVER...CLEAR SKIES ARE ANTICIPATED THIS
EVENING WITH LIGHT SOUTHERLY WINDS FROM THE GULF. OVERNIGHT LOWS WILL
RANGE FROM THE MID 20S ACROSS THE HILL COUNTRY TO NEAR 30 ACROSS
THE RIO GRANDE PLAINS. THURSDAY`S HIGH TEMPERATURES WILL BE 5 TO
10 DEGREES WARMER THAN TODAY`S HIGH AS SOUTHERLY FLOW REMAINS.
LONG TERM (FRIDAY THROUGH WEDNESDAY)...
A SURFACE HIGH PRESSURE RIDGE OVER THE AREA WILL CONTINUE TO BRING
SOUTHERLY WINDS FOR THE REST OF THE WORK WEEK...RESULTING IN ABOVE
SEASONAL TEMPERATURES ACROSS SOUTH CENTRAL TEXAS WITH HIGHS IN
THE MID 70S ON FRIDAY AND SATURDAY. SOUTHERLY WINDS AND MOISTURE
ARE EXPECTED TO INCREASE ON FRIDAY INTO THE UPCOMING WEEKEND AS AN
UPPER LEVEL LONG-WAVE TROUGH PUSHES ACROSS THE DESERT SOUTHWEST
REGION WHILE SENDING SHORT-WAVE PULSES ACROSS SOUTH CENTRAL TEXAS.
THIS OVERRUNNING PATTERN WILL PRODUCE VERY LIGHT RAIN MAINLY ALONG
AND EAST OF INTERSTATE 35 LATE FRIDAY AND SATURDAY. A COLD FRONT
IS EXPECTED TO PUSH ACROSS THE AREA EARLY SUNDAY AND STALLING
ALONG THE COASTAL PLAINS THROUGH MONDAY. THIS WILL KEEP THE AREA
MOSTLY CLOUDY WITH LOW CHANCES OF RAIN THROUGH THE PERIOD. BY
TUESDAY OF NEXT WEEK...A SHARP UPPER LEVEL SHORT-WAVE TROUGH IS
EXPECTED TO MOVE ACROSS THE SOUTHERN PLAINS WHILE INTERACTING WITH
THE WARM SECTOR OF THE STALL FRONTAL BOUNDARY OVER THE COASTAL
PLAINS. SINCE MEDIUM-RANGE MODELS ARE TRENDING WETTER EACH
RUN...OPTED TO INCREASE POPS UP TO 50 PERCENT ON TUESDAY MAINLY
ACROSS THE NORTHEAST HILL COUNTRY AND EASTERN COUNTIES. QPF
AMOUNTS ARE RANGING FROM ONE TENTH TO ONE HALF INCH. WEATHER
CONDITIONS WILL IMPROVE LATE TUESDAY INTO WEDNESDAY WITH ANOTHER
PLUNGE OF COLD AIR FOR THE MIDDLE OF NEXT WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 30 64 55 76 61 / 0 0 0 - 20
AUSTIN BERGSTROM INTL AIRPORT 23 62 49 75 55 / 0 0 0 - 20
NEW BRAUNFELS MUNI AIRPORT 25 63 47 76 56 / 0 0 0 - 20
BURNET MUNI AIRPORT 27 62 48 74 55 / 0 0 0 - 20
DEL RIO INTL AIRPORT 26 65 42 76 47 / 0 0 0 0 -
GEORGETOWN MUNI AIRPORT 26 63 52 74 57 / 0 0 0 - 20
HONDO MUNI AIRPORT 24 65 44 77 53 / 0 0 0 - 10
SAN MARCOS MUNI AIRPORT 26 62 48 74 56 / 0 0 0 10 20
LA GRANGE - FAYETTE REGIONAL 29 64 55 75 59 / 0 0 10 10 20
SAN ANTONIO INTL AIRPORT 29 65 50 76 59 / 0 0 0 - 20
STINSON MUNI AIRPORT 28 65 48 78 58 / 0 0 0 - 20
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...07
SYNOPTIC/GRIDS...04
PUBLIC SERVICE/DATA COLLECTION...33
AREA FORECAST DISCUSSION...UPDATED
NWS LUBBOCK TX
1139 AM CST TUE JAN 28 2014
.AVIATION...
VFR CONDITIONS WILL CONTINUE THROUGH THIS TAF CYCLE. WIND
DIRECTION WILL GRADUALLY SWING AROUND TO THE SOUTH TO SOUTHWEST
TONIGHT AND INCREASE IN SPEED THROUGH THE DAY TOMORROW.
JORDAN
&&
.PREV DISCUSSION... /ISSUED 539 AM CST TUE JAN 28 2014/
AVIATION...
A LOWER CLOUD DECK CONTINUED TO EDGE SOUTHEASTWARD OUT OF THE
PANHANDLE AND HAD ALREADY MOVED OVER KCDS WITH BROKEN CLOUDS AT
THE 8000 FOOT LAYER ABOVE GROUND LEVEL. THE SOUTHERN EDGE OF THIS
BAND LIKELY WILL SHRED AS IT EDGES SOUTH BUT MAY BE NEAR ENOUGH
KLBB FOR AT LEAST A FEW OR SCATTERED AT SOME POINT MID TO LATE THIS
MORNING. IT IS DIFFICULT TO SAY IF A SLIGHTLY LOWER BASE NEAR
4000 OR 5000 FEET MAY DEVELOP OVER KCDS...BUT MUCH LOWER THAN THAT
SEEMS MORE DIFFICULT OWING TO THE EXTREMELY DRY AIR IN THE LOWER
ATMOSPHERE. YET...THIS HAS BEEN INDICATED BY THE RAP SO CERTAINLY
NEEDS TO BE WATCHED. OTHERWISE...ONCE THE MID LEVEL SPEED MAX
DEPARTS OFF TO THE EAST-NORTHEAST THIS AFTERNOON...A SOLIDLY
DOWNWARD FORCING SHOULD DEVELOP WITH CLEAR SKIES WELL SUPPORTED.
AT THE SURFACE...THE RIDGE WILL NOSE SOUTHWARD WITH LIGHT SURFACE
WINDS TURNING TO SOUTH OR SOUTHWEST LATER TODAY AND TONIGHT. RMCQUEEN
PREV DISCUSSION... /ISSUED 402 AM CST TUE JAN 28 2014/
SHORT TERM...
A COLD AND VERY DRY SURFACE RIDGE WAS NOSING SOUTHWARD INTO THE AREA
EARLY THIS MORNING. MODEST NORTHEAST LOW LEVEL FLOW WAS GRADUALLY
DECREASING NORTH TO SOUTH AND WILL CONTINUE THIS TREND THROUGH THE
MORNING HOURS. WIND CHILL READINGS NEAR THE LOWER END OF ADVISORY
LEVELS SHOULD TAPER AWAY AS THOSE SPEEDS DROP FURTHER ALTHOUGH
DAYBREAK TEMPERATURES WILL START OUT IN THE SINGLE DIGITS MOST OF
THE AREA ON THE CAP-ROCK...EVEN SOME AREAS JUST BELOW ZERO ACROSS
NORTHWESTERN COUNTIES ESPECIALLY. SURFACE DEWPOINT READINGS IN THE
TEENS BELOW ZERO WITH THE DRIEST AIR LIKELY TO EDGE SOUTHWEST AWAY
FROM THE AREA BY MID TO LATE MORNING...NOT THAT ANY SIGNIFICANT
INCREASE IN DEWPOINTS WILL OCCUR. A LOW CLOUD DECK ACROSS THE
PANHANDLE SHOULD EDGE FURTHER SOUTH INTO OUR NORTH AND ESPECIALLY
NORTHEASTERN ZONES THIS MORNING...THOUGH EROSION WILL BE A FACTOR
AGAINST THAT EXTREMELY DRY AIR NEAR THE SURFACE. AND THIS CLOUD
LAYER IS LIKELY TO DISSOLVE BY LATE MORNING OR EARLY AFTERNOON MOST
OF THE AREA. ANOTHER AREA OF DEVELOPING LOW CLOUDS JUST TO OUR SOUTH
EARLY THIS MORNING ALSO SHOULD VEER TO THE SOUTHEAST AND DISSOLVE AS
WELL LATER THIS MORNING. HIGHS TODAY WILL STRUGGLE TO REACH FREEZING
IN SPITE OF PLENTY OF SUN MOST AREAS...HELD CLOSE TO THE PREVIOUS
FORECAST VALUES. A LIGHT SURFACE PRESSURE GRADIENT THIS EVENING WITH
CLEAR OR MOSTLY CLEAR SKIES SHOULD ALLOW RAPID COOLING. LOWS MAY BE
REACHED BY OR A LITTLE BEFORE MIDNIGHT WESTERN COUNTIES AS SURFACE
PRESSURE FALLS NEAR THE NEW MEXICO LINE WILL LEAD TO LOW LEVEL
SOUTHWEST BREEZES THAT SHOULD MIX INTO SLIGHTLY LESS COLD AIR LATER
TONIGHT. WIND CHILL READINGS MAY AGAIN DIP CLOSE TO ZERO ON THE
CAP-ROCK WITH THIS COMBINATION. RMCQUEEN
LONG TERM...
CHANGES IN THE COLD WEATHER PATTERN WILL BE QUICK TO RETURN TO MORE
SEASONABLE DRY AND WARM WEATHER. BY WEDNESDAY MORNING, THE SURFACE
RIDGE WILL BE SOUTHEAST OF THE AREA WITH SURFACE LEE TROUGHING BY
THE AFTERNOON. TEMPERATURES WILL BEGIN TO RAPIDLY RAMP UP ON
THURSDAY WITH CONTINUED LEE SIDE SURFACE TROUGHING. HOWEVER, A WEAK
WIND SHIFT WILL TRY TO WORK ITS WAY INTO THE REGION FROM THE
NORTHEAST. REGIONS WHERE DOWNSLOPING WILL TAKE PLACE WOULD LIKELY
SEE A SIGNIFICANT WARM UP. AREAS NOT EXPERIENCING DOWNSLOPING WINDS
WOULD LIKELY SEE LOWER TEMPERATURES CREATING A SHARP GRADIENT ON
THURSDAY AFTERNOON. LEE TROUGHING WILL CONTINUE ON FRIDAY WITH
TEMPERATURES WELL ABOVE SEASONAL AVERAGES. A MORE SIGNIFICANT
FRONTAL BOUNDARY WILL PASS THROUGH THE REGION ON SATURDAY WITH A
1028MB SURFACE RIDGE SETTLING INTO THE MID MISSISSIPPI VALLEY. THIS
WILL BRING TEMPERATURES DOWN THROUGH EARLY NEXT WEEK BUT CONFIDENCE
IN THE GFS ENSEMBLE TEMPERATURE FORECAST IS VERY LOW WITH HIGH
UNCERTAINTY.
THE UPPER LEVEL WEST COAST RIDGE BLOCKING PATTERN WILL BEGIN TO
BREAK DOWN BY THE END OF THE WEEK LEADING TO MOSTLY ZONAL FLOW ALOFT
TO START THE WEEKEND. A FEW SHORT WAVES WILL BE ABLE TO NEAR THE
REGION OVER THE WEEKEND BUT AN ABUNDANCE OF DRY AIR WILL LIKELY
PREVENT ANY PRECIPITATION FROM REACHING THE GROUND. THESE SHORT
WAVES WILL BRING IN MID AND HIGH LEVEL MOISTURE BUT LOWER LEVELS
WILL BE VERY DRY. A MORE SIGNIFICANT SHORT WAVE MAY FINALLY BRING
MUCH NEEDED PRECIPITATION TO THE AREA AROUND MONDAY INTO TUESDAY
NEXT WEEK. BOTH THE ECMWF AND GFS ARE FAIRLY SIMILAR IN THEIR
SOLUTIONS DRAWING SOME LOW LEVEL MOISTURE BACK INTO WEST TEXAS AHEAD
OF THIS PROGRESSIVE SHORT WAVE.
FIRE WEATHER...
FROM WEDNESDAY THROUGH FRIDAY, A PERIOD OF ELEVATED FIRE WEATHER
CONDITIONS MAY BE POSSIBLE. WINDS WILL BE BREEZY EACH AFTERNOON
DUE TO A DEEPENING SURFACE PRESSURE TROUGH TO THE WEST OF THE
REGION. TEMPERATURES WILL CLIMB TO SEASONAL AVERAGES ON WEDNESDAY
WITH TEMPERATURES WELL ABOVE AVERAGES FOR THURSDAY AND FRIDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 30 13 55 29 69 / 0 0 0 0 0
TULIA 30 10 52 29 72 / 0 0 0 0 0
PLAINVIEW 30 10 51 30 74 / 0 0 0 0 0
LEVELLAND 32 11 52 32 74 / 0 0 0 0 0
LUBBOCK 32 11 51 29 74 / 0 0 0 0 0
DENVER CITY 32 12 52 30 74 / 0 0 0 0 0
BROWNFIELD 32 11 52 31 74 / 0 0 0 0 0
CHILDRESS 33 13 48 27 69 / 0 0 0 0 0
SPUR 33 10 48 30 75 / 0 0 0 0 0
ASPERMONT 34 13 48 32 73 / 0 0 0 0 0
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
1124 AM CST TUE JAN 28 2014
.AVIATION...
/18 TAFS/
NO CONCERNS WITH VFR THE NEXT 24-30 HRS. AN UPPER DISTURBANCE IS
CONTINUING TO MOVE AWAY FROM THE AIRPORTS THIS MORNING WITH
SUBSIDENCE ALREADY ERODING MID LEVEL CLOUDS FROM DFW AND POINTS
NORTHEAST.
NORTH WINDS 10-15 KTS WILL DIMINISH TO 5 KTS OR LESS BY EARLY
EVENING...AS BROAD SURFACE HIGH PRESSURE SETTLES ACROSS THE
AREA. WINDS RETURN FROM SOUTH-SOUTHWEST AT 5-10 KTS BY WEDNESDAY
MORNING WITH THE SURFACE HIGH RETREATING SOUTH OF THE AREA.
05/
&&
.UPDATE...
THE WINTER PRECIPITATION HAS ENDED ACROSS OUR SOUTHERN COUNTIES
BUT ICY ROADS REMAIN ACROSS BELL...MILAM...AND ROBERTSON COUNTIES
DUE TO EARLIER FREEZING RAIN THIS MORNING. TEMPERATURES IN THESE
COUNTIES ARE CURRENTLY IN THE UPPER 20S AND LOWER 30S. THE GOOD
NEWS IS THAT TEMPERATURES WILL WARM INTO THE MID 30S THIS
AFTERNOON UNDER SUNNY SKIES AND THIS WILL HELP CLEAR THE ROADS OF
ANY ICE. HOWEVER...ANY RESIDUAL WATER THAT REMAINS ON THE ROADS
TONIGHT WILL REFREEZE AS TEMPERATURES FALL INTO THE TEENS AND
LOWER 20S TONIGHT.
ANOTHER COLD DAY WILL OCCUR ACROSS NORTH AND CENTRAL TEXAS TODAY
WITH TEMPERATURES ONLY REACHING THE 30S AND POSSIBLY LOWER 40S
THIS AFTERNOON. CLOUD COVER WILL PERSIST FOR MUCH OF THE DAY OVER
THE NORTHERN AND NORTHEASTERN COUNTIES...KEEPING AFTERNOON
TEMPERATURES IN THE LOWER 30S. MADE SOME ADJUSTMENTS TO
TEMPERATURES FOR TODAY AND ADJUSTED SKY TRENDS BUT OTHERWISE THE
CURRENT FORECAST IS ON TRACK FOR TODAY.
82/JLD
&&
.PREV DISCUSSION... /ISSUED 423 AM CST TUE JAN 28 2014/
BAND OF MID LEVEL PRECIPITATION CONTINUES TO STREAM ACROSS CENTRAL
AND EAST TEXAS THIS MORNING. THERE IS CURRENTLY AN ONGOING BATTLE
BETWEEN THE VERY DRY AIR IN THE LOW LEVELS THAT CONTINUES TO
ADVECT INTO THE REGION FROM THE NORTH AND THE PRECIPITATION FALLING
INTO THIS DRY AIR. SO FAR MOST CENTRAL TEXAS LOCATIONS HAVE ONLY
HAD SPRINKLES OR LIGHT SLEET...BUT IT APPEARS ENOUGH SATURATION
HAS OCCURRED TO ALLOW FOR SOME MEASURABLE AMOUNTS OF PRECIP TO
REACH THE SURFACE. THE SPECIAL 6Z SOUNDING FROM TEXAS A&M IN CLL
WAS EXTREMELY HELPFUL. IT DEPICTED A SIGNIFICANT WARM LAYER OF AIR
NEAR 800MB WITH A READING AT 6 DEG C. FURTHERMORE THE LEVELS BELOW
850MB WERE A BIT WARMER THAN FORECAST AS WELL. WHILE EVAPORATIVE
COOLING SHOULD COOL THE LOWER LEVELS BELOW FREEZING... THERE WAS
CONSIDERABLY LESS DRY AIR BETWEEN 800-850MB SUGGESTING LITTLE
EVAPORATIVE COOLING WILL TAKE PLACE IN THIS LAYER. THUS AM FAIRLY
CONFIDENT IN REMOVING THE MENTION OF SNOW...AND THE PRIMARY
PRECIPITATION TYPE IS EXPECTED TO BE LIGHT FREEZING RAIN WITH
PERHAPS SOME LIGHT SLEET. ALTHOUGH PRECIP AMOUNTS WILL ONLY REACH
ONE OR TWO HUNDREDTHS...THERE IS CONSIDERABLY MORE CONCERN FOR
FREEZING RAIN CAUSING TRAVEL IMPACTS THAN IF THE PRECIP TYPE WERE
SLEET/SNOW AS WAS EXPECTED. THEREFORE WE HAVE DECIDED TO ERR ON
THE SIDE OF CAUTION AND ISSUE A WINTER WEATHER ADVISORY FOR THE
FAR SOUTHERN ZONES THROUGH 9 AM FOR POSSIBLE LIGHT ICING. BELIEVE
THE PRECIP WILL COME TO AN END IN THIS AREA BY 6 OR 7 AM...AND
ALTHOUGH TEMPS WILL LIKELY STAY BELOW FREEZING UNTIL MIDDAY...THE
CONSIDERABLE DRY ADVECTION AT THE SURFACE SHOULD CLEAR VIA
SUBLIMATION ANY ICY PATCHES THAT DEVELOP BY MID MORNING.
OTHERWISE THE UPPER TROUGH AXIS WILL CLEAR THE REGION TODAY AND
PUSH MOST OF THE MID-HIGH CLOUD COVER TO THE SOUTHEAST. THE FLY IN
THE OINTMENT IS THAT ANOTHER AREA OF LOW LEVEL MOISTURE ACROSS
OKLAHOMA AND WEST TEXAS WILL BE MOVING INTO THE REGION. MODELS ARE
AT TREMENDOUS ODDS WITH REGARDS TO THIS MOISTURE TODAY. THE RUC IS
FORECASTING WIDESPREAD LOW CLOUDS FILLING IN ACROSS MUCH OF THE
AREA BY MIDDAY. MEANWHILE THE GFS IS SHOWING CLEAR SKIES. IF THESE
CLOUDS DO MATERIALIZE...TEMPS WILL BE COLDER THAN FORECAST...AND
LIKELY STUCK IN THE MID TO UPPER 20S. IN THE GRIDS HAVE TRIED TO
SHOW CLEARING THIS MORNING FOLLOWED BY SOME INCREASE IN CLOUDS
THIS AFTERNOON...BUT THE WORDING GETS AVERAGED OUT TO A
MEANINGLESS PARTLY SUNNY TERM. ANY LOW-MID CLOUDS THAT DO DEVELOP
TODAY SHOULD EVANESCE THIS EVENING AS SUBSIDENCE DRYING SPREADS
ACROSS THE REGION. A SURFACE HIGH WILL ALSO SLIDE ACROSS NORTH
TEXAS TONIGHT...WITH WINDS GOING NEARLY CALM FOR THE CENTRAL AND
SOUTHERN ZONES AROUND SUNRISE WEDNESDAY. THE RESULT SHOULD BE
EXCELLENT RADIATIONAL COOLING AND WITH DEWPOINTS IN THE SINGLE
DIGITS...TEMPS WILL CRATER INTO THE TEENS FOR MOST AREAS.
SOUTH WINDS RETURN WEDNESDAY AND SUNNY SKIES WILL HELP TEMPS
REBOUND INTO THE 40S FOR HIGHS. SOUTH WINDS CONTINUE TO INCREASE
WEDNESDAY NIGHT AND THURSDAY AND TEMPS WILL ALSO MODERATE. FIRE
WEATHER LOOKS TO BE A CONCERN ON THURSDAY IN THE WESTERN ZONES WITH
WINDS 20-25 MPH AND RH FALLING BELOW 30 PERCENT. THIS MAY WARRANT
A FIRE WEATHER WATCH...AND NEXT SHIFT WILL HAVE A LOOK AT THIS
AFTER COORDINATION WITH THE TEXAS FOREST SERVICE. WINDS RELAX ON
FRIDAY AS A SURFACE LOW AND WEAK FRONT SLIDE INTO THE NORTHERN
ZONES. MOST OF NORTH TEXAS WILL SEE SOUTHWEST WINDS FRIDAY WHICH
WILL BOOST TEMPS INTO THE 70S. THE NEXT FRONT IS EXPECTED TO
SLOWLY MOVE THROUGH THE REGION FRIDAY NIGHT AND SATURDAY AND IT
WILL BRING TEMPERATURES BACK TO NORMAL FOR THE WEEKEND. THERE MAY
BE ENOUGH MOISTURE IN THE EASTERN ZONES FOR SOME ISOLATED SHOWERS
SATURDAY ALONG THE FRONT.
LOOKING AHEAD TO NEXT WEEK...WE CONTINUE TO SEE WILD SWINGS FROM
MODEL RUN TO MODEL RUN...RUNNING THE GAMUT BETWEEN WARM AND DRY
TO SEVERE WEATHER TO WINTER STORM. OFTEN MODELS DISPLAY THEIR
WORST RUN TO RUN CONSISTENCY WHEN THE UPPER LEVEL PATTERN UNDERGOES
A SIGNIFICANT CHANGE. WHAT WE CAN SEE IN THE MODEL DATA IS THAT
THERE IS GOOD AGREEMENT THAT THE UPPER RIDGE OVER THE WESTERN U.S.
WILL BREAK DOWN AND ALLOW PACIFIC TROUGHS TO MOVE INTO THE CONUS.
IN A MACRO SENSE...THIS SHOULD BE GOOD FOR PRECIPITATION CHANCES
TO START OFF THE MONTH OF FEBRUARY. WHAT IS INTERESTING ABOUT THIS
PATTERN CHANGE IS THAT THE ADDITION OF UPPER LEVEL WAVE ENERGY
INTO THE WESTERN U.S. SHOULD CAUSE THE COLD CORE UPPER LEVEL LOW
CURRENTLY EAST OF HUDSON BAY AND ITS ASSOCIATED LONGWAVE TROUGH
THAT HAS BEEN RESPONSIBLE FOR THE RECENT COLD SPELL TO RETROGRADE
WESTWARD. THIS MEANS THE CENTRAL PART OF THE COUNTRY WILL SEE COLD
AIR PERSIST WITH AN ARCTIC FETCH WHILE PACIFIC ENERGY PROVIDES THE
LIFT AND FETCHES GULF MOISTURE FOR PRECIP. THE CURRENT CPC 8-14 DAY
FORECAST DOES SUPPORT THE HYPOTHESIS THAT THE CENTRAL U.S. IS
LOOKING AT COLDER AND WETTER THAN NORMAL WEATHER. NORTH TEXAS WILL
BE ON THE SOUTHERN CUSP OF THIS SETUP...WITH BELOW NORMAL TEMPS
AND PRECIPITATION FORECAST TO BE NEAR NORMAL. THUS IT LOOKS LIKE
FEBRUARY COULD START OFF INTERESTING WITH A FEW POTENTIAL WINTER
SYSTEMS WE WILL HAVE TO KEEP AN EYE ON. THE FIRST SYSTEM IS THE
ONE ON TUESDAY. THE LATEST MODEL FORECASTS SUGGEST MOST OF THE
WINTER WEATHER WILL BE JUST NORTH OF THE REGION...BUT IT WILL BEAR
WATCHING. HAVE KEPT SLIGHT CHANCE POPS MONDAY FOR SHOWERS...AND
INCREASED THEM TO CHANCE ON TUESDAY.
TR.92
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 35 19 45 31 62 / 0 0 0 0 0
WACO, TX 37 14 47 30 63 / 5 0 0 0 0
PARIS, TX 32 14 42 24 55 / 0 0 0 0 0
DENTON, TX 33 12 45 29 61 / 0 0 0 0 0
MCKINNEY, TX 33 12 44 28 59 / 0 0 0 0 0
DALLAS, TX 35 20 45 31 61 / 0 0 0 0 0
TERRELL, TX 37 15 45 29 59 / 0 0 0 0 0
CORSICANA, TX 38 17 46 31 60 / 5 0 0 0 0
TEMPLE, TX 37 18 48 30 64 / 10 0 0 0 0
MINERAL WELLS, TX 34 13 49 28 68 / 0 0 0 0 0
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
05/82
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
1034 AM CST TUE JAN 28 2014
.UPDATE...
THE WINTER PRECIPITATION HAS ENDED ACROSS OUR SOUTHERN COUNTIES
BUT ICY ROADS REMAIN ACROSS BELL...MILAM...AND ROBERTSON COUNTIES
DUE TO EARLIER FREEZING RAIN THIS MORNING. TEMPERATURES IN THESE
COUNTIES ARE CURRENTLY IN THE UPPER 20S AND LOWER 30S. THE GOOD
NEWS IS THAT TEMPERATURES WILL WARM INTO THE MID 30S THIS
AFTERNOON UNDER SUNNY SKIES AND THIS WILL HELP CLEAR THE ROADS OF
ANY ICE. HOWEVER...ANY RESIDUAL WATER THAT REMAINS ON THE ROADS
TONIGHT WILL REFREEZE AS TEMPERATURES FALL INTO THE TEENS AND
LOWER 20S TONIGHT.
ANOTHER COLD DAY WILL OCCUR ACROSS NORTH AND CENTRAL TEXAS TODAY
WITH TEMPERATURES ONLY REACHING THE 30S AND POSSIBLY LOWER 40S
THIS AFTERNOON. CLOUD COVER WILL PERSIST FOR MUCH OF THE DAY OVER
THE NORTHERN AND NORTHEASTERN COUNTIES...KEEPING AFTERNOON
TEMPERATURES IN THE LOWER 30S. MADE SOME ADJUSTMENTS TO
TEMPERATURES FOR TODAY AND ADJUSTED SKY TRENDS BUT OTHERWISE THE
CURRENT FORECAST IS ON TRACK FOR TODAY.
82/JLD
&&
.AVIATION...
NORTH WINDS OF 10 TO 15 KT WILL CONTINUE TODAY BEFORE DROPPING
BELOW 5 KT AROUND SUNSET. SKIES HAVE BRIEFLY BECOME MOSTLY CLEAR
IN THE METROPLEX...BUT 11-3.9 MICRON SATELLITE INDICATES ANOTHER
BATCH OF CLOUDS PUSHING IN FROM THE NORTH. WILL THEREFORE
MAINTAIN THE FORECAST OF CIGS IN THE 050-060 RANGE TODAY
SCATTERING OUT SHORTLY AFTER 00Z.
AN INTERESTING THING OF NOTE IS THE BAND OF SNOW WORKING ITS WAY
SOUTH THROUGH THE OKC AREA. WILL KEEP AN EYE ON IT...BUT MODELS
OVERWHELMINGLY SHUT THE PRECIP OFF AS ACTIVITY APPROACHES THE RED
RIVER LATER. THIS MAKES SENSE GIVEN THE EXCEPTIONALLY DRY AIR IN
PLACE OVER NORTH TEXAS.
OTHERWISE...SOUTH WINDS WILL RETURN BY MID DAY WEDNESDAY AS THE
SURFACE RIDGE MOVES EAST INTO THE LOWER MS VALLEY.
30
&&
.PREV DISCUSSION... /ISSUED 423 AM CST TUE JAN 28 2014/
BAND OF MID LEVEL PRECIPITATION CONTINUES TO STREAM ACROSS CENTRAL
AND EAST TEXAS THIS MORNING. THERE IS CURRENTLY AN ONGOING BATTLE
BETWEEN THE VERY DRY AIR IN THE LOW LEVELS THAT CONTINUES TO
ADVECT INTO THE REGION FROM THE NORTH AND THE PRECIPITATION FALLING
INTO THIS DRY AIR. SO FAR MOST CENTRAL TEXAS LOCATIONS HAVE ONLY
HAD SPRINKLES OR LIGHT SLEET...BUT IT APPEARS ENOUGH SATURATION
HAS OCCURRED TO ALLOW FOR SOME MEASURABLE AMOUNTS OF PRECIP TO
REACH THE SURFACE. THE SPECIAL 6Z SOUNDING FROM TEXAS A&M IN CLL
WAS EXTREMELY HELPFUL. IT DEPICTED A SIGNIFICANT WARM LAYER OF AIR
NEAR 800MB WITH A READING AT 6 DEG C. FURTHERMORE THE LEVELS BELOW
850MB WERE A BIT WARMER THAN FORECAST AS WELL. WHILE EVAPORATIVE
COOLING SHOULD COOL THE LOWER LEVELS BELOW FREEZING... THERE WAS
CONSIDERABLY LESS DRY AIR BETWEEN 800-850MB SUGGESTING LITTLE
EVAPORATIVE COOLING WILL TAKE PLACE IN THIS LAYER. THUS AM FAIRLY
CONFIDENT IN REMOVING THE MENTION OF SNOW...AND THE PRIMARY
PRECIPITATION TYPE IS EXPECTED TO BE LIGHT FREEZING RAIN WITH
PERHAPS SOME LIGHT SLEET. ALTHOUGH PRECIP AMOUNTS WILL ONLY REACH
ONE OR TWO HUNDREDTHS...THERE IS CONSIDERABLY MORE CONCERN FOR
FREEZING RAIN CAUSING TRAVEL IMPACTS THAN IF THE PRECIP TYPE WERE
SLEET/SNOW AS WAS EXPECTED. THEREFORE WE HAVE DECIDED TO ERR ON
THE SIDE OF CAUTION AND ISSUE A WINTER WEATHER ADVISORY FOR THE
FAR SOUTHERN ZONES THROUGH 9 AM FOR POSSIBLE LIGHT ICING. BELIEVE
THE PRECIP WILL COME TO AN END IN THIS AREA BY 6 OR 7 AM...AND
ALTHOUGH TEMPS WILL LIKELY STAY BELOW FREEZING UNTIL MIDDAY...THE
CONSIDERABLE DRY ADVECTION AT THE SURFACE SHOULD CLEAR VIA
SUBLIMATION ANY ICY PATCHES THAT DEVELOP BY MID MORNING.
OTHERWISE THE UPPER TROUGH AXIS WILL CLEAR THE REGION TODAY AND
PUSH MOST OF THE MID-HIGH CLOUD COVER TO THE SOUTHEAST. THE FLY IN
THE OINTMENT IS THAT ANOTHER AREA OF LOW LEVEL MOISTURE ACROSS
OKLAHOMA AND WEST TEXAS WILL BE MOVING INTO THE REGION. MODELS ARE
AT TREMENDOUS ODDS WITH REGARDS TO THIS MOISTURE TODAY. THE RUC IS
FORECASTING WIDESPREAD LOW CLOUDS FILLING IN ACROSS MUCH OF THE
AREA BY MIDDAY. MEANWHILE THE GFS IS SHOWING CLEAR SKIES. IF THESE
CLOUDS DO MATERIALIZE...TEMPS WILL BE COLDER THAN FORECAST...AND
LIKELY STUCK IN THE MID TO UPPER 20S. IN THE GRIDS HAVE TRIED TO
SHOW CLEARING THIS MORNING FOLLOWED BY SOME INCREASE IN CLOUDS
THIS AFTERNOON...BUT THE WORDING GETS AVERAGED OUT TO A
MEANINGLESS PARTLY SUNNY TERM. ANY LOW-MID CLOUDS THAT DO DEVELOP
TODAY SHOULD EVANESCE THIS EVENING AS SUBSIDENCE DRYING SPREADS
ACROSS THE REGION. A SURFACE HIGH WILL ALSO SLIDE ACROSS NORTH
TEXAS TONIGHT...WITH WINDS GOING NEARLY CALM FOR THE CENTRAL AND
SOUTHERN ZONES AROUND SUNRISE WEDNESDAY. THE RESULT SHOULD BE
EXCELLENT RADIATIONAL COOLING AND WITH DEWPOINTS IN THE SINGLE
DIGITS...TEMPS WILL CRATER INTO THE TEENS FOR MOST AREAS.
SOUTH WINDS RETURN WEDNESDAY AND SUNNY SKIES WILL HELP TEMPS
REBOUND INTO THE 40S FOR HIGHS. SOUTH WINDS CONTINUE TO INCREASE
WEDNESDAY NIGHT AND THURSDAY AND TEMPS WILL ALSO MODERATE. FIRE
WEATHER LOOKS TO BE A CONCERN ON THURSDAY IN THE WESTERN ZONES WITH
WINDS 20-25 MPH AND RH FALLING BELOW 30 PERCENT. THIS MAY WARRANT
A FIRE WEATHER WATCH...AND NEXT SHIFT WILL HAVE A LOOK AT THIS
AFTER COORDINATION WITH THE TEXAS FOREST SERVICE. WINDS RELAX ON
FRIDAY AS A SURFACE LOW AND WEAK FRONT SLIDE INTO THE NORTHERN
ZONES. MOST OF NORTH TEXAS WILL SEE SOUTHWEST WINDS FRIDAY WHICH
WILL BOOST TEMPS INTO THE 70S. THE NEXT FRONT IS EXPECTED TO
SLOWLY MOVE THROUGH THE REGION FRIDAY NIGHT AND SATURDAY AND IT
WILL BRING TEMPERATURES BACK TO NORMAL FOR THE WEEKEND. THERE MAY
BE ENOUGH MOISTURE IN THE EASTERN ZONES FOR SOME ISOLATED SHOWERS
SATURDAY ALONG THE FRONT.
LOOKING AHEAD TO NEXT WEEK...WE CONTINUE TO SEE WILD SWINGS FROM
MODEL RUN TO MODEL RUN...RUNNING THE GAMUT BETWEEN WARM AND DRY
TO SEVERE WEATHER TO WINTER STORM. OFTEN MODELS DISPLAY THEIR
WORST RUN TO RUN CONSISTENCY WHEN THE UPPER LEVEL PATTERN UNDERGOES
A SIGNIFICANT CHANGE. WHAT WE CAN SEE IN THE MODEL DATA IS THAT
THERE IS GOOD AGREEMENT THAT THE UPPER RIDGE OVER THE WESTERN U.S.
WILL BREAK DOWN AND ALLOW PACIFIC TROUGHS TO MOVE INTO THE CONUS.
IN A MACRO SENSE...THIS SHOULD BE GOOD FOR PRECIPITATION CHANCES
TO START OFF THE MONTH OF FEBRUARY. WHAT IS INTERESTING ABOUT THIS
PATTERN CHANGE IS THAT THE ADDITION OF UPPER LEVEL WAVE ENERGY
INTO THE WESTERN U.S. SHOULD CAUSE THE COLD CORE UPPER LEVEL LOW
CURRENTLY EAST OF HUDSON BAY AND ITS ASSOCIATED LONGWAVE TROUGH
THAT HAS BEEN RESPONSIBLE FOR THE RECENT COLD SPELL TO RETROGRADE
WESTWARD. THIS MEANS THE CENTRAL PART OF THE COUNTRY WILL SEE COLD
AIR PERSIST WITH AN ARCTIC FETCH WHILE PACIFIC ENERGY PROVIDES THE
LIFT AND FETCHES GULF MOISTURE FOR PRECIP. THE CURRENT CPC 8-14 DAY
FORECAST DOES SUPPORT THE HYPOTHESIS THAT THE CENTRAL U.S. IS
LOOKING AT COLDER AND WETTER THAN NORMAL WEATHER. NORTH TEXAS WILL
BE ON THE SOUTHERN CUSP OF THIS SETUP...WITH BELOW NORMAL TEMPS
AND PRECIPITATION FORECAST TO BE NEAR NORMAL. THUS IT LOOKS LIKE
FEBRUARY COULD START OFF INTERESTING WITH A FEW POTENTIAL WINTER
SYSTEMS WE WILL HAVE TO KEEP AN EYE ON. THE FIRST SYSTEM IS THE
ONE ON TUESDAY. THE LATEST MODEL FORECASTS SUGGEST MOST OF THE
WINTER WEATHER WILL BE JUST NORTH OF THE REGION...BUT IT WILL BEAR
WATCHING. HAVE KEPT SLIGHT CHANCE POPS MONDAY FOR SHOWERS...AND
INCREASED THEM TO CHANCE ON TUESDAY.
TR.92
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 35 19 45 31 62 / 0 0 0 0 0
WACO, TX 37 14 47 30 63 / 5 0 0 0 0
PARIS, TX 32 14 42 24 55 / 0 0 0 0 0
DENTON, TX 33 12 45 29 61 / 0 0 0 0 0
MCKINNEY, TX 33 12 44 28 59 / 0 0 0 0 0
DALLAS, TX 35 20 45 31 61 / 0 0 0 0 0
TERRELL, TX 37 15 45 29 59 / 0 0 0 0 0
CORSICANA, TX 38 17 46 31 60 / 5 0 0 0 0
TEMPLE, TX 37 18 48 30 64 / 10 0 0 0 0
MINERAL WELLS, TX 34 13 49 28 68 / 0 0 0 0 0
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
05/82
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
539 AM CST TUE JAN 28 2014
.AVIATION...
A LOWER CLOUD DECK CONTINUED TO EDGE SOUTHEASTWARD OUT OF THE
PANHANDLE AND HAD ALREADY MOVED OVER KCDS WITH BROKEN CLOUDS AT
THE 8000 FOOT LAYER ABOVE GROUND LEVEL. THE SOUTHERN EDGE OF THIS
BAND LIKELY WILL SHRED AS IT EDGES SOUTH BUT MAY BE NEAR ENOUGH
KLBB FOR AT LEAST A FEW OR SCATTERED AT SOME POINT MID TO LATE THIS
MORNING. IT IS DIFFICULT TO SAY IF A SLIGHTLY LOWER BASE NEAR
4000 OR 5000 FEET MAY DEVELOP OVER KCDS...BUT MUCH LOWER THAN THAT
SEEMS MORE DIFFICULT OWING TO THE EXTREMELY DRY AIR IN THE LOWER
ATMOSPHERE. YET...THIS HAS BEEN INDICATED BY THE RAP SO CERTAINLY
NEEDS TO BE WATCHED. OTHERWISE...ONCE THE MID LEVEL SPEED MAX
DEPARTS OFF TO THE EAST-NORTHEAST THIS AFTERNOON...A SOLIDLY
DOWNWARD FORCING SHOULD DEVELOP WITH CLEAR SKIES WELL SUPPORTED.
AT THE SURFACE...THE RIDGE WILL NOSE SOUTHWARD WITH LIGHT SURFACE
WINDS TURNING TO SOUTH OR SOUTHWEST LATER TODAY AND TONIGHT. RMCQUEEN
&&
.PREV DISCUSSION... /ISSUED 402 AM CST TUE JAN 28 2014/
SHORT TERM...
A COLD AND VERY DRY SURFACE RIDGE WAS NOSING SOUTHWARD INTO THE AREA
EARLY THIS MORNING. MODEST NORTHEAST LOW LEVEL FLOW WAS GRADUALLY
DECREASING NORTH TO SOUTH AND WILL CONTINUE THIS TREND THROUGH THE
MORNING HOURS. WIND CHILL READINGS NEAR THE LOWER END OF ADVISORY
LEVELS SHOULD TAPER AWAY AS THOSE SPEEDS DROP FURTHER ALTHOUGH
DAYBREAK TEMPERATURES WILL START OUT IN THE SINGLE DIGITS MOST OF
THE AREA ON THE CAP-ROCK...EVEN SOME AREAS JUST BELOW ZERO ACROSS
NORTHWESTERN COUNTIES ESPECIALLY. SURFACE DEWPOINT READINGS IN THE
TEENS BELOW ZERO WITH THE DRIEST AIR LIKELY TO EDGE SOUTHWEST AWAY
FROM THE AREA BY MID TO LATE MORNING...NOT THAT ANY SIGNIFICANT
INCREASE IN DEWPOINTS WILL OCCUR. A LOW CLOUD DECK ACROSS THE
PANHANDLE SHOULD EDGE FURTHER SOUTH INTO OUR NORTH AND ESPECIALLY
NORTHEASTERN ZONES THIS MORNING...THOUGH EROSION WILL BE A FACTOR
AGAINST THAT EXTREMELY DRY AIR NEAR THE SURFACE. AND THIS CLOUD
LAYER IS LIKELY TO DISSOLVE BY LATE MORNING OR EARLY AFTERNOON MOST
OF THE AREA. ANOTHER AREA OF DEVELOPING LOW CLOUDS JUST TO OUR SOUTH
EARLY THIS MORNING ALSO SHOULD VEER TO THE SOUTHEAST AND DISSOLVE AS
WELL LATER THIS MORNING. HIGHS TODAY WILL STRUGGLE TO REACH FREEZING
IN SPITE OF PLENTY OF SUN MOST AREAS...HELD CLOSE TO THE PREVIOUS
FORECAST VALUES. A LIGHT SURFACE PRESSURE GRADIENT THIS EVENING WITH
CLEAR OR MOSTLY CLEAR SKIES SHOULD ALLOW RAPID COOLING. LOWS MAY BE
REACHED BY OR A LITTLE BEFORE MIDNIGHT WESTERN COUNTIES AS SURFACE
PRESSURE FALLS NEAR THE NEW MEXICO LINE WILL LEAD TO LOW LEVEL
SOUTHWEST BREEZES THAT SHOULD MIX INTO SLIGHTLY LESS COLD AIR LATER
TONIGHT. WIND CHILL READINGS MAY AGAIN DIP CLOSE TO ZERO ON THE
CAP-ROCK WITH THIS COMBINATION. RMCQUEEN
LONG TERM...
CHANGES IN THE COLD WEATHER PATTERN WILL BE QUICK TO RETURN TO MORE
SEASONABLE DRY AND WARM WEATHER. BY WEDNESDAY MORNING, THE SURFACE
RIDGE WILL BE SOUTHEAST OF THE AREA WITH SURFACE LEE TROUGHING BY
THE AFTERNOON. TEMPERATURES WILL BEGIN TO RAPIDLY RAMP UP ON
THURSDAY WITH CONTINUED LEE SIDE SURFACE TROUGHING. HOWEVER, A WEAK
WIND SHIFT WILL TRY TO WORK ITS WAY INTO THE REGION FROM THE
NORTHEAST. REGIONS WHERE DOWNSLOPING WILL TAKE PLACE WOULD LIKELY
SEE A SIGNIFICANT WARM UP. AREAS NOT EXPERIENCING DOWNSLOPING WINDS
WOULD LIKELY SEE LOWER TEMPERATURES CREATING A SHARP GRADIENT ON
THURSDAY AFTERNOON. LEE TROUGHING WILL CONTINUE ON FRIDAY WITH
TEMPERATURES WELL ABOVE SEASONAL AVERAGES. A MORE SIGNIFICANT
FRONTAL BOUNDARY WILL PASS THROUGH THE REGION ON SATURDAY WITH A
1028MB SURFACE RIDGE SETTLING INTO THE MID MISSISSIPPI VALLEY. THIS
WILL BRING TEMPERATURES DOWN THROUGH EARLY NEXT WEEK BUT CONFIDENCE
IN THE GFS ENSEMBLE TEMPERATURE FORECAST IS VERY LOW WITH HIGH
UNCERTAINTY.
THE UPPER LEVEL WEST COAST RIDGE BLOCKING PATTERN WILL BEGIN TO
BREAK DOWN BY THE END OF THE WEEK LEADING TO MOSTLY ZONAL FLOW ALOFT
TO START THE WEEKEND. A FEW SHORT WAVES WILL BE ABLE TO NEAR THE
REGION OVER THE WEEKEND BUT AN ABUNDANCE OF DRY AIR WILL LIKELY
PREVENT ANY PRECIPITATION FROM REACHING THE GROUND. THESE SHORT
WAVES WILL BRING IN MID AND HIGH LEVEL MOISTURE BUT LOWER LEVELS
WILL BE VERY DRY. A MORE SIGNIFICANT SHORT WAVE MAY FINALLY BRING
MUCH NEEDED PRECIPITATION TO THE AREA AROUND MONDAY INTO TUESDAY
NEXT WEEK. BOTH THE ECMWF AND GFS ARE FAIRLY SIMILAR IN THEIR
SOLUTIONS DRAWING SOME LOW LEVEL MOISTURE BACK INTO WEST TEXAS AHEAD
OF THIS PROGRESSIVE SHORT WAVE.
FIRE WEATHER...
FROM WEDNESDAY THROUGH FRIDAY, A PERIOD OF ELEVATED FIRE WEATHER
CONDITIONS MAY BE POSSIBLE. WINDS WILL BE BREEZY EACH AFTERNOON
DUE TO A DEEPENING SURFACE PRESSURE TROUGH TO THE WEST OF THE
REGION. TEMPERATURES WILL CLIMB TO SEASONAL AVERAGES ON WEDNESDAY
WITH TEMPERATURES WELL ABOVE AVERAGES FOR THURSDAY AND FRIDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 30 13 55 29 69 / 0 0 0 0 0
TULIA 30 10 52 29 72 / 0 0 0 0 0
PLAINVIEW 30 10 51 30 74 / 0 0 0 0 0
LEVELLAND 32 11 52 32 74 / 0 0 0 0 0
LUBBOCK 32 11 51 29 74 / 0 0 0 0 0
DENVER CITY 32 12 52 30 74 / 0 0 0 0 0
BROWNFIELD 32 11 52 31 74 / 0 0 0 0 0
CHILDRESS 33 13 48 27 69 / 0 0 0 0 0
SPUR 33 10 48 30 75 / 0 0 0 0 0
ASPERMONT 34 13 48 32 73 / 0 0 0 0 0
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
99/99/05
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
527 AM CST TUE JAN 28 2014
.AVIATION...
NORTH WINDS OF 10 TO 15 KT WILL CONTINUE TODAY BEFORE DROPPING
BELOW 5 KT AROUND SUNSET. SKIES HAVE BRIEFLY BECOME MOSTLY CLEAR
IN THE METROPLEX...BUT 11-3.9 MICRON SATELLITE INDICATES ANOTHER
BATCH OF CLOUDS PUSHING IN FROM THE NORTH. WILL THEREFORE
MAINTAIN THE FORECAST OF CIGS IN THE 050-060 RANGE TODAY
SCATTERING OUT SHORTLY AFTER 00Z.
AN INTERESTING THING OF NOTE IS THE BAND OF SNOW WORKING ITS WAY
SOUTH THROUGH THE OKC AREA. WILL KEEP AN EYE ON IT...BUT MODELS
OVERWHELMINGLY SHUT THE PRECIP OFF AS ACTIVITY APPROACHES THE RED
RIVER LATER. THIS MAKES SENSE GIVEN THE EXCEPTIONALLY DRY AIR IN
PLACE OVER NORTH TEXAS.
OTHERWISE...SOUTH WINDS WILL RETURN BY MID DAY WEDNESDAY AS THE
SURFACE RIDGE MOVES EAST INTO THE LOWER MS VALLEY.
30
&&
.PREV DISCUSSION... /ISSUED 423 AM CST TUE JAN 28 2014/
BAND OF MID LEVEL PRECIPITATION CONTINUES TO STREAM ACROSS CENTRAL
AND EAST TEXAS THIS MORNING. THERE IS CURRENTLY AN ONGOING BATTLE
BETWEEN THE VERY DRY AIR IN THE LOW LEVELS THAT CONTINUES TO
ADVECT INTO THE REGION FROM THE NORTH AND THE PRECIPITATION FALLING
INTO THIS DRY AIR. SO FAR MOST CENTRAL TEXAS LOCATIONS HAVE ONLY
HAD SPRINKLES OR LIGHT SLEET...BUT IT APPEARS ENOUGH SATURATION
HAS OCCURRED TO ALLOW FOR SOME MEASURABLE AMOUNTS OF PRECIP TO
REACH THE SURFACE. THE SPECIAL 6Z SOUNDING FROM TEXAS A&M IN CLL
WAS EXTREMELY HELPFUL. IT DEPICTED A SIGNIFICANT WARM LAYER OF AIR
NEAR 800MB WITH A READING AT 6 DEG C. FURTHERMORE THE LEVELS BELOW
850MB WERE A BIT WARMER THAN FORECAST AS WELL. WHILE EVAPORATIVE
COOLING SHOULD COOL THE LOWER LEVELS BELOW FREEZING... THERE WAS
CONSIDERABLY LESS DRY AIR BETWEEN 800-850MB SUGGESTING LITTLE
EVAPORATIVE COOLING WILL TAKE PLACE IN THIS LAYER. THUS AM FAIRLY
CONFIDENT IN REMOVING THE MENTION OF SNOW...AND THE PRIMARY
PRECIPITATION TYPE IS EXPECTED TO BE LIGHT FREEZING RAIN WITH
PERHAPS SOME LIGHT SLEET. ALTHOUGH PRECIP AMOUNTS WILL ONLY REACH
ONE OR TWO HUNDREDTHS...THERE IS CONSIDERABLY MORE CONCERN FOR
FREEZING RAIN CAUSING TRAVEL IMPACTS THAN IF THE PRECIP TYPE WERE
SLEET/SNOW AS WAS EXPECTED. THEREFORE WE HAVE DECIDED TO ERR ON
THE SIDE OF CAUTION AND ISSUE A WINTER WEATHER ADVISORY FOR THE
FAR SOUTHERN ZONES THROUGH 9 AM FOR POSSIBLE LIGHT ICING. BELIEVE
THE PRECIP WILL COME TO AN END IN THIS AREA BY 6 OR 7 AM...AND
ALTHOUGH TEMPS WILL LIKELY STAY BELOW FREEZING UNTIL MIDDAY...THE
CONSIDERABLE DRY ADVECTION AT THE SURFACE SHOULD CLEAR VIA
SUBLIMATION ANY ICY PATCHES THAT DEVELOP BY MID MORNING.
OTHERWISE THE UPPER TROUGH AXIS WILL CLEAR THE REGION TODAY AND
PUSH MOST OF THE MID-HIGH CLOUD COVER TO THE SOUTHEAST. THE FLY IN
THE OINTMENT IS THAT ANOTHER AREA OF LOW LEVEL MOISTURE ACROSS
OKLAHOMA AND WEST TEXAS WILL BE MOVING INTO THE REGION. MODELS ARE
AT TREMENDOUS ODDS WITH REGARDS TO THIS MOISTURE TODAY. THE RUC IS
FORECASTING WIDESPREAD LOW CLOUDS FILLING IN ACROSS MUCH OF THE
AREA BY MIDDAY. MEANWHILE THE GFS IS SHOWING CLEAR SKIES. IF THESE
CLOUDS DO MATERIALIZE...TEMPS WILL BE COLDER THAN FORECAST...AND
LIKELY STUCK IN THE MID TO UPPER 20S. IN THE GRIDS HAVE TRIED TO
SHOW CLEARING THIS MORNING FOLLOWED BY SOME INCREASE IN CLOUDS
THIS AFTERNOON...BUT THE WORDING GETS AVERAGED OUT TO A
MEANINGLESS PARTLY SUNNY TERM. ANY LOW-MID CLOUDS THAT DO DEVELOP
TODAY SHOULD EVANESCE THIS EVENING AS SUBSIDENCE DRYING SPREADS
ACROSS THE REGION. A SURFACE HIGH WILL ALSO SLIDE ACROSS NORTH
TEXAS TONIGHT...WITH WINDS GOING NEARLY CALM FOR THE CENTRAL AND
SOUTHERN ZONES AROUND SUNRISE WEDNESDAY. THE RESULT SHOULD BE
EXCELLENT RADIATIONAL COOLING AND WITH DEWPOINTS IN THE SINGLE
DIGITS...TEMPS WILL CRATER INTO THE TEENS FOR MOST AREAS.
SOUTH WINDS RETURN WEDNESDAY AND SUNNY SKIES WILL HELP TEMPS
REBOUND INTO THE 40S FOR HIGHS. SOUTH WINDS CONTINUE TO INCREASE
WEDNESDAY NIGHT AND THURSDAY AND TEMPS WILL ALSO MODERATE. FIRE
WEATHER LOOKS TO BE A CONCERN ON THURSDAY IN THE WESTERN ZONES WITH
WINDS 20-25 MPH AND RH FALLING BELOW 30 PERCENT. THIS MAY WARRANT
A FIRE WEATHER WATCH...AND NEXT SHIFT WILL HAVE A LOOK AT THIS
AFTER COORDINATION WITH THE TEXAS FOREST SERVICE. WINDS RELAX ON
FRIDAY AS A SURFACE LOW AND WEAK FRONT SLIDE INTO THE NORTHERN
ZONES. MOST OF NORTH TEXAS WILL SEE SOUTHWEST WINDS FRIDAY WHICH
WILL BOOST TEMPS INTO THE 70S. THE NEXT FRONT IS EXPECTED TO
SLOWLY MOVE THROUGH THE REGION FRIDAY NIGHT AND SATURDAY AND IT
WILL BRING TEMPERATURES BACK TO NORMAL FOR THE WEEKEND. THERE MAY
BE ENOUGH MOISTURE IN THE EASTERN ZONES FOR SOME ISOLATED SHOWERS
SATURDAY ALONG THE FRONT.
LOOKING AHEAD TO NEXT WEEK...WE CONTINUE TO SEE WILD SWINGS FROM
MODEL RUN TO MODEL RUN...RUNNING THE GAMUT BETWEEN WARM AND DRY
TO SEVERE WEATHER TO WINTER STORM. OFTEN MODELS DISPLAY THEIR
WORST RUN TO RUN CONSISTENCY WHEN THE UPPER LEVEL PATTERN UNDERGOES
A SIGNIFICANT CHANGE. WHAT WE CAN SEE IN THE MODEL DATA IS THAT
THERE IS GOOD AGREEMENT THAT THE UPPER RIDGE OVER THE WESTERN U.S.
WILL BREAK DOWN AND ALLOW PACIFIC TROUGHS TO MOVE INTO THE CONUS.
IN A MACRO SENSE...THIS SHOULD BE GOOD FOR PRECIPITATION CHANCES
TO START OFF THE MONTH OF FEBRUARY. WHAT IS INTERESTING ABOUT THIS
PATTERN CHANGE IS THAT THE ADDITION OF UPPER LEVEL WAVE ENERGY
INTO THE WESTERN U.S. SHOULD CAUSE THE COLD CORE UPPER LEVEL LOW
CURRENTLY EAST OF HUDSON BAY AND ITS ASSOCIATED LONGWAVE TROUGH
THAT HAS BEEN RESPONSIBLE FOR THE RECENT COLD SPELL TO RETROGRADE
WESTWARD. THIS MEANS THE CENTRAL PART OF THE COUNTRY WILL SEE COLD
AIR PERSIST WITH AN ARCTIC FETCH WHILE PACIFIC ENERGY PROVIDES THE
LIFT AND FETCHES GULF MOISTURE FOR PRECIP. THE CURRENT CPC 8-14 DAY
FORECAST DOES SUPPORT THE HYPOTHESIS THAT THE CENTRAL U.S. IS
LOOKING AT COLDER AND WETTER THAN NORMAL WEATHER. NORTH TEXAS WILL
BE ON THE SOUTHERN CUSP OF THIS SETUP...WITH BELOW NORMAL TEMPS
AND PRECIPITATION FORECAST TO BE NEAR NORMAL. THUS IT LOOKS LIKE
FEBRUARY COULD START OFF INTERESTING WITH A FEW POTENTIAL WINTER
SYSTEMS WE WILL HAVE TO KEEP AN EYE ON. THE FIRST SYSTEM IS THE
ONE ON TUESDAY. THE LATEST MODEL FORECASTS SUGGEST MOST OF THE
WINTER WEATHER WILL BE JUST NORTH OF THE REGION...BUT IT WILL BEAR
WATCHING. HAVE KEPT SLIGHT CHANCE POPS MONDAY FOR SHOWERS...AND
INCREASED THEM TO CHANCE ON TUESDAY.
TR.92
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 37 19 45 31 62 / 0 0 0 0 0
WACO, TX 39 14 47 30 63 / 5 0 0 0 0
PARIS, TX 35 14 42 24 55 / 0 0 0 0 0
DENTON, TX 34 12 45 29 61 / 0 0 0 0 0
MCKINNEY, TX 35 12 44 28 59 / 0 0 0 0 0
DALLAS, TX 36 20 45 31 61 / 0 0 0 0 0
TERRELL, TX 37 15 45 29 59 / 0 0 0 0 0
CORSICANA, TX 39 17 46 31 60 / 5 0 0 0 0
TEMPLE, TX 38 18 48 30 64 / 10 0 0 0 0
MINERAL WELLS, TX 35 13 49 28 68 / 0 0 0 0 0
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 9 AM CST THIS MORNING FOR TXZ158-
162-174-175.
&&
$$
30/92
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
423 AM CST TUE JAN 28 2014
.DISCUSSION...
BAND OF MID LEVEL PRECIPITATION CONTINUES TO STREAM ACROSS CENTRAL
AND EAST TEXAS THIS MORNING. THERE IS CURRENTLY AN ONGOING BATTLE
BETWEEN THE VERY DRY AIR IN THE LOW LEVELS THAT CONTINUES TO
ADVECT INTO THE REGION FROM THE NORTH AND THE PRECIPITATION FALLING
INTO THIS DRY AIR. SO FAR MOST CENTRAL TEXAS LOCATIONS HAVE ONLY
HAD SPRINKLES OR LIGHT SLEET...BUT IT APPEARS ENOUGH SATURATION
HAS OCCURRED TO ALLOW FOR SOME MEASURABLE AMOUNTS OF PRECIP TO
REACH THE SURFACE. THE SPECIAL 6Z SOUNDING FROM TEXAS A&M IN CLL
WAS EXTREMELY HELPFUL. IT DEPICTED A SIGNIFICANT WARM LAYER OF AIR
NEAR 800MB WITH A READING AT 6 DEG C. FURTHERMORE THE LEVELS BELOW
850MB WERE A BIT WARMER THAN FORECAST AS WELL. WHILE EVAPORATIVE
COOLING SHOULD COOL THE LOWER LEVELS BELOW FREEZING... THERE WAS
CONSIDERABLY LESS DRY AIR BETWEEN 800-850MB SUGGESTING LITTLE
EVAPORATIVE COOLING WILL TAKE PLACE IN THIS LAYER. THUS AM FAIRLY
CONFIDENT IN REMOVING THE MENTION OF SNOW...AND THE PRIMARY
PRECIPITATION TYPE IS EXPECTED TO BE LIGHT FREEZING RAIN WITH
PERHAPS SOME LIGHT SLEET. ALTHOUGH PRECIP AMOUNTS WILL ONLY REACH
ONE OR TWO HUNDREDTHS...THERE IS CONSIDERABLY MORE CONCERN FOR
FREEZING RAIN CAUSING TRAVEL IMPACTS THAN IF THE PRECIP TYPE WERE
SLEET/SNOW AS WAS EXPECTED. THEREFORE WE HAVE DECIDED TO ERR ON
THE SIDE OF CAUTION AND ISSUE A WINTER WEATHER ADVISORY FOR THE
FAR SOUTHERN ZONES THROUGH 9 AM FOR POSSIBLE LIGHT ICING. BELIEVE
THE PRECIP WILL COME TO AN END IN THIS AREA BY 6 OR 7 AM...AND
ALTHOUGH TEMPS WILL LIKELY STAY BELOW FREEZING UNTIL MIDDAY...THE
CONSIDERABLE DRY ADVECTION AT THE SURFACE SHOULD CLEAR VIA
SUBLIMATION ANY ICY PATCHES THAT DEVELOP BY MID MORNING.
OTHERWISE THE UPPER TROUGH AXIS WILL CLEAR THE REGION TODAY AND
PUSH MOST OF THE MID-HIGH CLOUD COVER TO THE SOUTHEAST. THE FLY IN
THE OINTMENT IS THAT ANOTHER AREA OF LOW LEVEL MOISTURE ACROSS
OKLAHOMA AND WEST TEXAS WILL BE MOVING INTO THE REGION. MODELS ARE
AT TREMENDOUS ODDS WITH REGARDS TO THIS MOISTURE TODAY. THE RUC IS
FORECASTING WIDESPREAD LOW CLOUDS FILLING IN ACROSS MUCH OF THE
AREA BY MIDDAY. MEANWHILE THE GFS IS SHOWING CLEAR SKIES. IF THESE
CLOUDS DO MATERIALIZE...TEMPS WILL BE COLDER THAN FORECAST...AND
LIKELY STUCK IN THE MID TO UPPER 20S. IN THE GRIDS HAVE TRIED TO
SHOW CLEARING THIS MORNING FOLLOWED BY SOME INCREASE IN CLOUDS
THIS AFTERNOON...BUT THE WORDING GETS AVERAGED OUT TO A
MEANINGLESS PARTLY SUNNY TERM. ANY LOW-MID CLOUDS THAT DO DEVELOP
TODAY SHOULD EVANESCE THIS EVENING AS SUBSIDENCE DRYING SPREADS
ACROSS THE REGION. A SURFACE HIGH WILL ALSO SLIDE ACROSS NORTH
TEXAS TONIGHT...WITH WINDS GOING NEARLY CALM FOR THE CENTRAL AND
SOUTHERN ZONES AROUND SUNRISE WEDNESDAY. THE RESULT SHOULD BE
EXCELLENT RADIATIONAL COOLING AND WITH DEWPOINTS IN THE SINGLE
DIGITS...TEMPS WILL CRATER INTO THE TEENS FOR MOST AREAS.
SOUTH WINDS RETURN WEDNESDAY AND SUNNY SKIES WILL HELP TEMPS
REBOUND INTO THE 40S FOR HIGHS. SOUTH WINDS CONTINUE TO INCREASE
WEDNESDAY NIGHT AND THURSDAY AND TEMPS WILL ALSO MODERATE. FIRE
WEATHER LOOKS TO BE A CONCERN ON THURSDAY IN THE WESTERN ZONES WITH
WINDS 20-25 MPH AND RH FALLING BELOW 30 PERCENT. THIS MAY WARRANT
A FIRE WEATHER WATCH...AND NEXT SHIFT WILL HAVE A LOOK AT THIS
AFTER COORDINATION WITH THE TEXAS FOREST SERVICE. WINDS RELAX ON
FRIDAY AS A SURFACE LOW AND WEAK FRONT SLIDE INTO THE NORTHERN
ZONES. MOST OF NORTH TEXAS WILL SEE SOUTHWEST WINDS FRIDAY WHICH
WILL BOOST TEMPS INTO THE 70S. THE NEXT FRONT IS EXPECTED TO
SLOWLY MOVE THROUGH THE REGION FRIDAY NIGHT AND SATURDAY AND IT
WILL BRING TEMPERATURES BACK TO NORMAL FOR THE WEEKEND. THERE MAY
BE ENOUGH MOISTURE IN THE EASTERN ZONES FOR SOME ISOLATED SHOWERS
SATURDAY ALONG THE FRONT.
LOOKING AHEAD TO NEXT WEEK...WE CONTINUE TO SEE WILD SWINGS FROM
MODEL RUN TO MODEL RUN...RUNNING THE GAMUT BETWEEN WARM AND DRY
TO SEVERE WEATHER TO WINTER STORM. OFTEN MODELS DISPLAY THEIR
WORST RUN TO RUN CONSISTENCY WHEN THE UPPER LEVEL PATTERN UNDERGOES
A SIGNIFICANT CHANGE. WHAT WE CAN SEE IN THE MODEL DATA IS THAT
THERE IS GOOD AGREEMENT THAT THE UPPER RIDGE OVER THE WESTERN U.S.
WILL BREAK DOWN AND ALLOW PACIFIC TROUGHS TO MOVE INTO THE CONUS.
IN A MACRO SENSE...THIS SHOULD BE GOOD FOR PRECIPITATION CHANCES
TO START OFF THE MONTH OF FEBRUARY. WHAT IS INTERESTING ABOUT THIS
PATTERN CHANGE IS THAT THE ADDITION OF UPPER LEVEL WAVE ENERGY
INTO THE WESTERN U.S. SHOULD CAUSE THE COLD CORE UPPER LEVEL LOW
CURRENTLY EAST OF HUDSON BAY AND ITS ASSOCIATED LONGWAVE TROUGH
THAT HAS BEEN RESPONSIBLE FOR THE RECENT COLD SPELL TO RETROGRADE
WESTWARD. THIS MEANS THE CENTRAL PART OF THE COUNTRY WILL SEE COLD
AIR PERSIST WITH AN ARCTIC FETCH WHILE PACIFIC ENERGY PROVIDES THE
LIFT AND FETCHES GULF MOISTURE FOR PRECIP. THE CURRENT CPC 8-14 DAY
FORECAST DOES SUPPORT THE HYPOTHESIS THAT THE CENTRAL U.S. IS
LOOKING AT COLDER AND WETTER THAN NORMAL WEATHER. NORTH TEXAS WILL
BE ON THE SOUTHERN CUSP OF THIS SETUP...WITH BELOW NORMAL TEMPS
AND PRECIPITATION FORECAST TO BE NEAR NORMAL. THUS IT LOOKS LIKE
FEBRUARY COULD START OFF INTERESTING WITH A FEW POTENTIAL WINTER
SYSTEMS WE WILL HAVE TO KEEP AN EYE ON. THE FIRST SYSTEM IS THE
ONE ON TUESDAY. THE LATEST MODEL FORECASTS SUGGEST MOST OF THE
WINTER WEATHER WILL BE JUST NORTH OF THE REGION...BUT IT WILL BEAR
WATCHING. HAVE KEPT SLIGHT CHANCE POPS MONDAY FOR SHOWERS...AND
INCREASED THEM TO CHANCE ON TUESDAY.
TR.92
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 37 19 45 31 62 / 0 0 0 0 0
WACO, TX 39 13 47 30 63 / 5 0 0 0 0
PARIS, TX 36 14 42 24 55 / 0 0 0 0 0
DENTON, TX 35 12 45 29 61 / 0 0 0 0 0
MCKINNEY, TX 36 12 44 28 59 / 0 0 0 0 0
DALLAS, TX 37 20 45 31 61 / 0 0 0 0 0
TERRELL, TX 38 15 45 29 59 / 0 0 0 0 0
CORSICANA, TX 39 17 46 31 60 / 5 0 0 0 0
TEMPLE, TX 38 17 48 30 64 / 5 0 0 0 0
MINERAL WELLS, TX 35 13 49 28 68 / 0 0 0 0 0
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 9 AM CST THIS MORNING FOR TXZ158-
162-174-175.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
919 PM CST WED JAN 29 2014
.UPDATE...
LATEST RAP AND 00Z NAM CONTINUE TO SHOW DEEP OMEGA APPROACHING 10
MICROBARS/SEC JUST AHEAD OF THE SURFACE LOW IN THE DEEP SOUTHWEST
WARM ADVECTION FIELD. THIS INCLUDES THE DENDRITE GROWTH ZONE.
GOING FORECAST HAS 1-3" OF SNOW ACCUMULATION AND THAT SEEMS
REASONABLE. LOOKING LIKE POTENTIAL FOR ONE HOUR OF 1/4 TO 1/2 MILE
VISIBILITY WITH UP TO AN INCH ACCUMULATION RIGHT AROUND
MIDDAY...SO COULD IMPACT THE LUNCH HOUR RUSH. WITH WINDS GUSTING
TO 25-30 KNOTS BLOWING SNOW COULD BE A PROBLEM ESPECIALLY ON
WEST-EAST ROADS.
WILL ISSUE A SPECIAL WEATHER STATEMENT TO ADDRESS BRIEF BURST OF
SNOW AND BLOWING AND DRIFTING ISSUES.
&&
.AVIATION/06Z TAFS/...
WINDS WILL GRADUALLY PICK UP FROM THE SOUTH OVERNIGHT AND
THURSDAY. 00Z NAM AND 02Z RAP FORECASTS HAVE SIMILAR TIMING ON 3-4
HOURS OF SNOW STARTING AT KMSN AROUND 17Z AND THE SOUTHEAST WI TAF
SITES BETWEEN 18Z AND 19Z. LOOKS LIKE A POTENTIAL BURST OF
MODERATE TO BRIEFLY HEAVY SNOW POSSIBLE WITH MOST OF THE 1-2"
ACCUMULATION OCCURING IN 1-2 HOURS. WITH GUSTS OF 25 TO 30 KNOTS
BLOWING SNOW COULD BE A PROBLEM AS WELL AS THE FALLING SNOW.
TOOK DOWN VISIBILITIES INTO LIFR RANGE ON THE PREVIOUS TAF PACKAGE AND
WILL NEED TO CONSIDER SOME 1/2 MILE VALUES ON THE 06Z UPDATE GIVEN
THE STRONG DEEP LIFT SHOWN.
THE WINDS SHOULD DIMINISH IN THE AFTERNOON AS THE GRADIENT WEAKENS
ALONG THE ADVANCING COLD FRONT.
&&
.MARINE...
WINDS GUSTING TO 33 KNOTS AT SHEBOYGAN CMAN AND ARE GUSTING CLOSE
TO 20 KNOTS FURTHER SOUTH AND SHOULD CONTINUE TO GRADUALLY
INCREASE OVERNIGHT AS GRADIENT INCREASES AHEAD OF APPROACHING
FRONT.
WAVE FORECAST IS SOMEWHAT PROBLEMATIC BECAUSE ICE ANALYSIS HAS
BEEN SHOWING ICE WELL OFFSHORE BUT EVENING SATELLITE IMAGES
INDICATED SOME OFFSHORE DRIFT. WAVE WATCH 3 HAS ZERO WAVES BECAUSE
OF ASSUMED ICE AND WILL ROLL WITH THAT IN THE GRIDS. HOWEVER...WILL
CONTINUE TO MENTION HIGHER WAVES IN OPEN WATERS IN THE MARINE
WARNING MESSAGE.
&&
.PREV DISCUSSION... /ISSUED 320 PM CST WED JAN 29 2014/
SHORT TERM...
TONIGHT...FORECAST CONFIDENCE HIGH
EXPECTING EARLY LOWS BETWEEN 00Z AND 03Z THEN STEADY OUT AND
SLOWLY RISE WITH STRONG WARM ADVECTION AHEAD OF SHORT WAVE TROUGH.
INCREASING CLOUDS...BUT NO PCPN INTO THE CWA OVERNIGHT AS BEST
LAYER Q-VECTOR CONVERGENCE AND LAYER FRONTOGENESIS REMAINS
NORTHWEST OF THE CWA UNTIL AFTER 12Z.
THURSDAY...FORECAST CONFIDENCE HIGH
SEVERAL INGREDIENTS COMING INTO PLAY FOR A PERIOD OF SNOW. 250
MILLIBAR JET MAXIMUM WILL BE AIMING INTO SRN WI WITH STRONG
DIVERGENCE SIGNAL. 280-290K ISENTROPIC PLOTS SHOW 2.0-2.5 G/KG
MIXING RATIOS THOUGH INITIALLY THERE IS DRY AIR TO OVERCOME. NAM
IS MOST PRONOUNCED WITH THIS BY HAVING FAIRLY HIGH CONDENSATION
PRESSURE DEFICITS IN THE SE IN THE MORNING. SATURATION WILL TAKE
HOLD AS FORCING MECHANISMS INCREASE. GFS/ECMWF AND NAM ALL SHOW
IMPRESSIVE DIFFERENTIAL CYCLONIC VORTICITY ADVECTION IN THE 12-18Z
TIME FRAME. WHILE THE NAM IS THE WETTER SOLUTION WITH CONSIDERABLY
HIGHER QPF IN THE NW CWA...STEERED CLOSER TO THE CONSENSUS OF THE
GFS/ECMWF ON QPF AMOUNTS. CAME UP WITH NEAR 3 INCH AMOUNTS IN THE
FAR NORTH AND AROUND 1-1.5 IN THE SOUTH. PONDERED ADVISORY IN THE
FAR NORTH BUT DECIDED AGAINST IT WITH BORDERLINE AMOUNTS IN SUCH A
SMALL PORTION OF THE NORTHERN COUNTIES. 18Z NAM TRENDING FURTHER
NORTH TOO. SOME BLOWING LIKELY THOUGH SNOW WILL BE OF A WETTER
CONSISTENCY THAN PREVIOUS SO THINKING BLOWING NOT AS BIG OF AN
ISSUE.
THURSDAY NIGHT THROUGH SATURDAY...FORECAST CONFIDENCE MEDIUM
THE ARCTIC COLD FRONT WILL BE PASSING THROUGH SRN WI LATE THU AFT
AND EARLY THU EVE. NWLY WINDS AND COLD ADVECTION TO BRING LOW
TEMPS IN THE SINGLE DIGITS WITH SOME BELOW ZERO READINGS POSSIBLE
NORTH AND WEST OF MADISON. POLAR HIGH PRESSURE TO THEN SETTLE OVER
WI FRI AND FRI NT.
HOWEVER...A SFC TROUGH WILL EXTEND FROM THE SRN PLAINS INTO THE
OHIO RIVER VALLEY FOR FRI NT INTO SAT AS A SHORTWAVE TROUGH IN
SWLY FLOW ALOFT APPROACHES THE REGION. A CONSENSUS OF MODELS DOES
BRING THE LOW TO MID LEVEL FRONTOGENESIS AND SNOWFALL INTO AT
LEAST THE SE HALF OF THE CWA FOR SAT. THUS WENT WITH LIKELY POPS
OVER SE WI WITH A 1-3 INCH FORECAST...HIGHER TOWARD THE IL BORDER.
ARCTIC AIR TO REMAIN OVER THE REGION FOR THIS PERIOD BUT NOT AS
COLD AS EARLIER IN THE WEEK. NO WIND CHILL ADVISORIES ARE
ANTICIPATED.
LONG TERM...
SUNDAY THROUGH WEDNESDAY...FORECAST CONFIDENCE MEDIUM
NWLY WINDS TO REINFORCE THE ARCTIC AIR SAT NT INTO SUN AFTER THE
SNOWFALL ON SAT WITH ANOTHER WEAK REINFORCEMENT EXPECTED MON NT.
IN BETWEEN THESE FRONTS POLAR HIGH PRESSURE WILL PREVAIL WITH
CONTINUED BELOW NORMAL TEMPS. A LARGE LOW PRESSURE SYSTEM WILL
THEN TRACK FROM THE SRN PLAINS THROUGH THE OHIO RIVER VALLEY FOR
TUE AND TUE NT WITH ONLY SLIGHT CHANCES OF SNOW OVER SRN WI. NLY
WINDS BEHIND THIS SYSTEM WILL BRING COLDER ARCTIC AIR INTO THE
REGION.
AVIATION/00Z TAFS/...VFR SKC INTO THIS EVENING. MAIN ISSUE TONIGHT
WILL BE LOW LEVEL WIND SHEAR WITH APPROACH OF STRONG SOUTHWEST 850
JET CORE. HAVE MAINTAINED MENTION OF THIS IN LATEST SET OF TAFS.
MVFR CIGS/IFR VSBYS BECOME INCREASINGLY MORE LIKELY ON THURSDAY AS
NEXT TROUGH MOVES THROUGH THE AREA. SW SURFACE WINDS WILL BE GUSTY
SO SOME BLOWING SNOW LIKELY EVEN THOUGH AMOUNTS NOT GREAT.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 9 PM CST THURSDAY FOR LMZ643>646.
&&
$$
UPDATE...CRAVEN
TONIGHT/THURSDAY AND AVIATION/MARINE...COLLAR
THURSDAY NIGHT THROUGH WEDNESDAY...GEHRING
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
737 PM CST WED JAN 29 2014
.UPDATE...
ISSUED AT 737 PM CST WED JAN 29 2014
29.21Z...22Z AND 23Z RAP CYCLES HAVE BEEN FOLLOWING THE 29.18Z
NAM/GFS CLOSELY...SUGGESTING MORE QPF THAN PREVIOUSLY FORECAST
NORTH OF INTERSTATE 90. AFTER COLLABORATION WITH NEIGHBORING
OFFICES...HAVE RAISED QPF/SNOWFALL AMOUNTS TOWARDS A CONSENSUS OF
THE AFOREMENTIONED MODELS. THE NEW UPDATES GET SNOWFALL TOTALS
CLOSE TO WARNING CRITERIA. HAVE HELD OFF ON A WARNING AT THIS
TIME WITH AMOUNTS IN THE 4 TO 6 INCH RANGE OVER TAYLOR/CLARK
COUNTIES...BUT CLOSE MONITORING OF THIS SYSTEM WILL BE NEEDED.
REGARDING THE METEOROLOGICAL REASONING FOR THE HIGHER QPF AND
SHIFT NORTH...THE 500MB SHORTWAVE SEEN ON WATER VAPOR OVER CENTRAL
MN IS NOW PROGGED TO TAKE A SLIGHTLY FARTHER NORTH TRACK AND BE
STRONGER.
CONSIDERED ALSO SEGMENTING THE ADVISORY TO DELAY THE START TIME
FOR MOST WISCONSIN COUNTIES. HOWEVER...SINCE THE TIME SPLIT WOULD
HAVE ONLY BEEN FOR 2 HOURS...DECIDED TO LEAVE THE ADVISORY TIMES
ALONE. DID SEGMENT THE WSW IN AN ATTEMPT TO ACCOUNT FOR THE SLOWER
ARRIVAL INTO WISCONSIN.
UPDATE ISSUED AT 452 PM CST WED JAN 29 2014
HAVE INCLUDED TAYLOR COUNTY INTO THE WINTER WEATHER ADVISORY.
29.18Z NAM/GFS AND 29.12Z ECMWF ALL HAVE SHOWN A NORTHWARD SHIFT
TO THE SNOWFALL TRACK...WITH THE 29.18Z NAM EVEN SUGGESTING
POTENTIAL OF GETTING CLOSE TO WARNING CRITERIA IN SOME SPOTS. WITH
THE NORTHWARD SHIFT...FELT A NEED TO ACCOUNT FOR THIS BY
INCLUDING TAYLOR COUNTY.
ANOTHER ISSUE NOT ADDRESSED RIGHT NOW IN THE HAZARD OR CURRENT
FORECAST IS THE 29.18Z GUIDANCE SUGGESTING A LITTLE SLOWER TIMING
OF THE PRECIPITATION. FOR EXAMPLE...THE SNOW MAY START IN THE LSE
AREA UNTIL THE END OF THE MORNING COMMUTE...I.E. 8-9 AM. WILL BE
EVALUATING THIS OVER THE NEXT FEW HOURS TO SEE IF SOME OF THE
ADVISORY START TIMES NEED TO BE DELAYED.
INTERESTING TO NOTE...THE SNOW FOR TOMORROW MORNING IS CURRENTLY
IN CENTRAL MONTANA. VISIBILITIES THERE RANGE FROM 1/2 TO 1 SM.
ONE LAST ITEM...THE 29.18Z NAM DOES SHOW A LITTLE MORE WOUND-UP
LOW COMPARED TO ITS 12Z RUN. IF THIS COMES TRUE...THERE COULD BE A
BIT MORE BLOWING AND DRIFTING OF THE SNOW THAT FALLS THURSDAY
MORNING.
&&
.SHORT TERM...(TONIGHT THROUGH THURSDAY NIGHT)
ISSUED AT 259 PM CST WED JAN 29 2014
MAIN FORECAST CONCERN THROUGH THE SHORT TERM IS ACCUMULATING SNOW
LATE TONIGHT INTO THURSDAY AND IMPACT ON MORNING COMMUTE.
WATER VAPOR IMAGERY LOOP/GFS 500MB ANALYSIS SHOW A TROUGH OF LOW
PRESSURE OVER CENTRAL CANADA. WARM AIR ADVECTION AHEAD OF THIS WAVE
HAS PUSHED TEMPERATURES INTO THE TEENS AND LOWER 20S. ATTENTION THEN
TURNS TOWARD A STRONGER WAVE CRASHING INTO THE INTERMOUNTAIN
WEST/NORTHERN ROCKIES VIA 150-170KT JET OFF THE PACIFIC NORTHWEST.
THIS WAVE IS SET TO IMPACT THE AREA LATE TONIGHT INTO THURSDAY WITH
ACCUMULATING SNOW.
WEATHER WILL BEGIN QUIET INITIALLY WITH JUST SOME INCREASE IN
HIGH/MID CLOUD OVERNIGHT AS A COLD FRONT SLIPS SOUTHEAST AND STALLS
OUT ACROSS CENTRAL WI/SOUTHERN MN. SOUTHWEST WINDS AND CLOUD COVER
INCREASE AHEAD OF THE FRONTAL BOUNDARY WILL KEEP TEMPERATURES FAIRLY
STEADY IN THE TEENS. THEN...MODELS IN VERY GOOD AGREEMENT IN
BRINGING A FAIRLY STRONG 700-300MB PV-ANOMALY ACROSS THE BOUNDARY IN
THE 12-18Z TIME FRAME ALONG WITH INCREASING FRONTOGENESIS CENTERED
MAINLY IN THE 850-700MB LAYER. NAM ALSO INDICATES STRONG OMEGA IN THE
-12 TO -18C LAYER FOR DENDRITIC GROWTH POTENTIAL...BUT BUFKIT IS
ONLY SHOWING SNOW-TO-LIQUID RATIOS MAINLY IN THE 12-15:1 RANGE. THIS
IS PROBABLY DUE TO A SMALLER DGZ LESS THAN 100MB AND GOOD AMOUNT OF
WIND SHEAR THROUGH THIS LAYER. NONETHELESS...LOOKS LIKE THE
COMBINATION OF STRONG AGEOSTROPHIC MOTION WITH LEFT EXIT REGION OF
140-150KT JET/FRONTOGENESIS/PV-ANOMALY WILL PRODUCE A FAIRLY BROAD
AREA OF 2-4 INCHES ACROSS THE CWA. THE HEAVIEST SNOW AXIS LOOKS TO
BE CENTERED ALONG THE I-90/94 CORRIDOR REGION IN THE NWS LA CROSSE
FORECAST AREA INTO EAST CENTRAL WI. THE HEAVIEST SNOW RATES AS
ALLUDED TO ABOVE LOOKS LIKE IT WILL OCCUR IN THE 12Z-15Z TIME
FRAME...OR RIGHT IN THE HEART OF THE MORNING COMMUTE WHEN
VISIBILITIES COULD FALL TO 1/2SM AT TIMES. APPEARS THE BULK OF THE
ACCUMULATING SNOW MAY BE OVER WITH BY MID-AFTERNOON...BUT THINKING
THAT THERE MAY BE SOME DRIFTING SNOW ISSUES FOR AWHILE WITH 15-25
MPH WINDS PUSHING IN BEHIND THE DEPARTING WAVE. WITH ALL THIS IN
MIND...HAVE HOISTED A WINTER WEATHER ADVISORY FOR THE ANTICIPATED 2-
4 INCHES OF SNOWFALL VALID FROM 4 AM THROUGH 6 PM THURSDAY.
FRIGID WIND CHILLS THEN BECOME AN ISSUE AGAIN FOR A GOOD PORTION OF
THE AREA THURSDAY NIGHT WITH VALUES DROPPING INTO THE 20-30 BELOW
RANGE. WILL EVENTUALLY HAVE TO HOIST ANOTHER ADVISORY TO COVER THIS.
WILL HOLD OFF UNTIL THE WINTER WEATHER ADVISORY FOR SNOW IS DONE TO
AVOID ANY HEADLINE CONFUSION.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 259 PM CST WED JAN 29 2014
MAIN FORECAST CONCERN FOCUSED ON THE LATE FRIDAY NIGHT THROUGH
SATURDAY TIME FRAME. MODELS SHOWING A WAVE OF LOW PRESSURE
ORIGINATING OUT OF THE COLORADO ROCKIES/SOUTHERN PLAINS MOVING
NORTHEAST ACROSS SOUTHERN/CENTRAL IL. THE ECMWF IS THE FARTHEST
NORTH WITH A SHIELD OF SNOW NORTH OF THE LOW TRACK...PUSHING IT AL
THE WAY INTO THE LA CROSSE FORECAST AREA WHILE OTHER MODELS KEEPING
IT MAINLY SOUTH OF I-90. WENT WITH A MODEL CONSENSUS POP OF 20-40
PERCENT PROBABILITY AT THIS POINT...BUT WILL HAVE TO KEEP A CLOSE
EYE ON THE TRACK AND ADJUST POPS AS NECESSARY. EVEN IF THE ECMWF IS
RIGHT...ONLY LOOKS LIKE AN INCH OR LESS FOR THE AREA. SATURDAY NIGHT
THROUGH MONDAY NIGHT LOOKING QUIET AND CONTINUED COLDER THAN NORMAL
WITH THE MAIN STORM TRACK ACROSS THE SOUTHERN/EASTERN PORTIONS OF
THE CONUS. TEMPERATURE-WISE...LOOK FOR LOWS SATURDAY NIGH THROUGH
MONDAY NIGHT IN THE SINGLE DIGITS ABOVE AND BELOW ZERO WITH HIGHS ON
SUNDAY IN THE SINGLE DIGITS/TENS ABOVE ZERO...WARMING SLIGHTLY
INTO THE TEENS TO AROUND 20 ON MONDAY.
SOUTHERN STREAM BECOMES MORE ACTIVE THIS NEXT WEEK WITH POSSIBLY
ANOTHER STORM SYSTEM BRUSHING FAR SOUTHERN PORTIONS OF THE AREA
TUESDAY/TUESDAY NIGHT WITH LIGHT SNOW.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 536 PM CST WED JAN 29 2014
A DRY AIRMASS LEFTOVER FROM AN ARCTIC HIGH PRESSURE RIDGE CROSSING
THE TAF SITES THIS MORNING WILL ALLOW VFR CONDITIONS TO CONTINUE
THROUGH MUCH OF TONIGHT. HOWEVER...A TIGHT PRESSURE GRADIENT NOW
IN PLACE...WHICH DOES NOT LOOK TO RELAX MUCH UNTIL LATE
TONIGHT...MEANS WINDS ARE AN ISSUE. EXPECTING RST TO CONTINUE TO
HAVE GUSTS OF 25-30 KT THIS EVENING...THEN DIMINISHING AROUND
MIDNIGHT AS THE NOCTURNAL INVERSION STRENGTHENS A LITTLE BIT.
BOTH TAF SITES ARE LIKELY TO EXPERIENCE LOW LEVEL WIND SHEAR AS
WELL...AS SOUTHWEST 45-55 KT WINDS AT 1500-2000 FT ABOVE THE
SURFACE EXIST. LOOK FOR THE LOW LEVEL WIND SHEAR TO END TOWARDS
10-12Z.
SNOW ACROSS MONTANA WILL SPREAD INTO THE TAF SITES THURSDAY
MORNING. TIMING HAS SLOWED DOWN JUST A LITTLE FROM THE 18Z TAFS.
STILL IT APPEARS VISIBILITIES WILL RAPIDLY DROP FROM VFR TO LIFR
IN A MATTER OF 1-2 HRS. SNOW SHOULD MOVE THROUGH QUICKLY...THOUGH...
SUCH THAT IS DONE BY 18Z. WINDS INCREASING OUT OF THE NORTHWEST
AND GUSTING 20-25 KT COULD PRODUCE SOME MVFR VISIBILITIES AT KRST
DURING THE AFTERNOON. CEILINGS FOR THE MOST PART SHOULD BE MVFR
DURING THE DAY...THOUGH RST COULD LOWER TO IFR IN THE MORNING.
TOTAL SNOWFALL AMOUNTS ON THE ORDER OF 2 TO 3 INCHES ARE
LIKELY...MUCH OF WHICH COMING IN A 4 HR WINDOW THURSDAY MORNING.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER WEATHER ADVISORY FROM 4 AM TO 6 PM CST THURSDAY FOR
WIZ017-029-032>034-041>044-053.
MN...WINTER WEATHER ADVISORY FROM 4 AM TO 6 PM CST THURSDAY FOR
MNZ079-086>088-094>096.
IA...WINTER WEATHER ADVISORY FROM 4 AM TO 6 PM CST THURSDAY FOR
IAZ008-009.
&&
$$
UPDATE...AJ
SHORT TERM...DAS
LONG TERM....DAS
AVIATION...AJ
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1157 PM MST WED JAN 29 2014
.UPDATE...
ISSUED AT 1154 PM MST WED JAN 29 2014
UPDATED TO THROW IN EL PASO AND THE LOWER ELEVATIONS OF TELLER
COUNTY AS WELL AS HUERFANO COUNTY INTO THE HIGH WIND WARNING FOR
TONIGHT. GETTING GUSTS IN THE AIR FORCE ACADEMY AREA OF AROUND 65
MPH...AND ALTHOUGH CROSS-SECTIONS OFF THE 00Z NAM12 DID NOT LOOK
ANY MORE IMPRESSIVE THAN THE PREVIOUS RUN...THE LOCAL 4KM WRF AND
HRRR HAVE COME IN STRONGER. CURRENT OBSERVATIONS SUPPORT THE TREND
SO HAVE UPDATED TO INCREASE WINDS FOR LOCATIONS MAINLY ALONG AND
WEST OF I-25. WILL HAVE TO WATCH WESTERN LAS ANIMAS COUNTY CLOSELY AS
THIS AREA MAY SEE HIGH WINDS IF HRRR IS CORRECT. IF SO THESE MAY
MATERIALIZE AROUND 12Z. -KT
UPDATE ISSUED AT 616 PM MST WED JAN 29 2014
PIKES PEAK SENSOR REGISTERED A GUST TO 80 MPH AT 530 PM. WITH
WINDS EXPECTED TO INCREASE THROUGH THE NIGHT WITH THE INCOMING JET...DECIDED
TO ADD THE HIGHER ELEVATIONS OF PIKES PEAK...THE WETS...AND
SANGRES TO THE HIGH WIND WARNING AND TO BUMP UP THE START TIME TO
NOW. THINK THAT THE MAJORITY OF THESE STRONGER WINDS WILL STAY
CONFINED TO THE HIGHER PEAKS BEFORE SPREADING INTO THE LOWER
ELEVATIONS OF THE SOUTHERN SANGRES AFTER MIDNIGHT. HAVE INCREASED
WINDS IN THE GRIDS TO ACCOUNT FOR CURRENT CONDITIONS. WILL HAVE TO
WATCH THE MESONET SENSORS CLOSELY OVER THE NEXT SEVERAL HOURS TO
SEE IF MTN WAVE DEVELOPS AND HELPS TO SPREAD THESE STRONG WINDS
INTO THE LOWER ELEVATIONS OF THE NORTHERN SANGRES AND PIKES PEAK REGION.
MTN WAVE PARAMETERS DO NOT LOOK IMPRESSIVE ENOUGH YET TO INCLUDE
THE LOWER ELEVATIONS JUST YET...BUT WILL BE MONITORING THE 00Z
RUNS AND HIGH RES MODELS CLOSELY AS THEY ARRIVE. -KT
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 256 PM MST WED JAN 29 2014
NOTE...CORRECTION SENT AS THIS MORNINGS SHORT TERM AND AVIATION AFD
SECTIONS WERE ACCIDENTALLY SENT OUT IN THE PREVIOUS AFTERNOON AFD
PACKAGE...
...SNOW HEADING FOR THE CONTDVD...
CURRENTLY...A STRONG AND MOIST PACIFIC JET STREAM IS TRANSLATING
ACROSS THE WEST COAST AND INTO THE GREAT BASIN REGION...WITH SNOW
STARTING UP ACROSS NORTHWESTERN COLORADO AT THIS TIME. FURTHER
EAST...A WIDE RANGE OF TEMPERATURES FROM THE MID 40S TO UPPER 50S
ARE IN PLACE ACROSS THE HIGHER TERRAIN ALONG WEST OF I-25 TO THE MID
30S IN THE LOWER ARKANSAS RIVER VALLEY...WHICH FAILED TO MIX OUT AND
STILL HAS SOME SNOW COVER AT THIS TIME.
TONIGHT AND TOMORROW...STRONG JET CONTINUES TO TRANSLATE ACROSS THE
ROCKIES...SPREADING SNOW...HEAVY AT TIMES...AND STRONG WINDS ACROSS
THE CENTRAL AND SOUTHWEST MTS. CURRENT WINTER STORM WARNINGS AND
ADVISORIES REMAINING ON TRACK...THOUGH HAVE INCLUDED THE UPPER
ARKANSAS RIVER VALLEY INTO AN ADVISORY. STILL LOOKING LIKE SNOW
ACCUMULATIONS OF 8 TO 18 INCHES WILL BE POSSIBLE ACROSS THE HIGHER
ELEVATIONS OF THE CENTRAL AND SOUTHWEST MTS BY LATE THURSDAY
AFTERNOON...WITH 3 TO 6 INCHES POSSIBLE ACROSS THE LOWER ELEVATIONS.
IN ADDITION...STRONG WESTERLY WINDS OF 25 TO 45 MPH WILL CREATE
DANGEROUS DRIVING CONDITIONS OVER THE HIGHER PASSES IN BLOWING AND
DRIFTING SNOW.
THESE STRONG WINDS WILL ALSO MOVE ACROSS THE EASTERN MTS AND
IMMEDIATE ADJACENT PLAINS LATER TONIGHT AND EARLY THURSDAY MORNING.
MODEL SOUNDINGS AND CROSS SECTIONS INDICATING A BRIEF WINDOW OF
WEAK REVERSE SHEAR TO LAMINAR FLOW ACROSS THE PIKES PEAK REGION FROM
AROUND 03Z TO 09Z WITH A BETTER SET UP FOR STRONG DOWNSLOPE WINDS
ACROSS THE SOUTHERN SANGRE DE CRISTO MTS...WHERE HAVE UPGRADED THE
CURRENT HIGH WIND WATCH TO A WARNING FOR ZONES 74 AND 75 WITH GUSTS
UP TO 80 MPH POSSIBLE. WITH THAT SAID...IT WILL STILL BE WINDY
TONIGHT ACROSS THE REST OF THE EASTERN MTS...WITH WEST WINDS OF 20
TO 40 MPH AND OCCASIONAL GUSTS TO 60 MPH.
AS THE JET CONTINUES TO SLOWLY SAG ACROSS THE STATE THROUGH THE DAY
TOMORROW....WILL SEE WINDS SLOWLY DIMINISHING FROM NORTHWEST TO
SOUTHEAST ACROSS THE HIGHER TERRAIN. THIS WILL ALLOW FOR LOWERING
PRESSURES ACROSS THE SOUTHERN I-25 CORRIDOR AND NORTHEASTERN NEW
MEXICO...OWNING TO UPSLOPE FLOW DEVELOPING ACROSS THE EASTERN PLAINS
THROUGH THE LATE MORNING AND AFTERNOON. AS FOR PRECIPITATION THE
WESTERLY FLOW AND UVV ASSOCIATED WITH THE JET WILL KEEP THE
POTENTIAL FOR SCATTED SHOWERS ACROSS THE EASTERN MTS AND IMMEDIATE
ADJACENT PLAINS THROUGH THE LATE MORNING AND AFTERNOON.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 256 PM MST WED JAN 29 2014
...HEAVY SNOW FOR THE CONTDVD...WITH SOME SNOW POSSIBLE OTHER
REGIONS...
LATEST SIMULATIONS CONTINUE TO INDICATE AN ACTIVE
PERIOD...ESPECIALLY THE FIRST PART OF THE LONG TERM FCST PERIOD.
THURSDAY NIGHT THE FLOW AT MID LVLS WILL TRANSITION FROM WEST TO
WSW...AND THIS WILL ALLOW THE HEAVY SNOW WHICH WILL BE FALLING OVER
THE C MTNS DURING THE FIRST PART OF THE NIGHT TO TRANSLATE SOUTHWARD
TOWARDS THE SAN JUANS. WITH FAVORABLE OROGRAPHICS AND ABUNDANT
MOISTURE...SNOWFALL RATES OVER THE CONTDVD WILL BE HEAVY.
LOCALLY STRONG WINDS WILL BE POSSIBLE ACROSS ALL OF THE
CONTDVD...BUT THE STRONGEST WINDS WILL SHIFT SWD DURING THE
NIGHTTIME HOURS. SNOWFALL RATES OF 1-2"/HR ARE LIKELY ALONG THE
CONTDVD THU NITE.
SOME SNOW WILL BE POSSIBLE OVER THE PIKES PEAK REGION THU NITE. IT
APPEARS THE OVERALL BEST FORCING WILL BE FROM THE TOP OF THE PALMER
DVD/PIKES PEAK NORTHWARD...SO AT THIS TIME...I AM NOT EXPECTING TOO
MUCH SNOW FOR FRIDAY MORNINGS RUSH HOUR. HOWEVER 1-3" ARE NOT OUT OF
THE QUESTION FOR N EL PASO COUNTY...WITH HEAVIER AMOUNTS POSSIBLE IN
TELLER COUNTY.
I SHOULD NOTE THAT IF THE JET DOES TRACK A BIT FARTHER NORTH THAN
GUIDANCE INDICATES...THEN MUCH HEAVIER SNOW COULD AFFECT THE PIKES
PEAK REGION. HOWEVER TRENDS IN THE GUIDANCE THE LAST COUPLE OF DAYS
HAVE BEEN PUSHING THE BEST FORCING FARTHER NORTH.
DURING THE DAY FRIDAY THE SNOW WILL GRADUALLY DIMINISH OVER THE
CONTDVD. IT STILL WILL SNOW STEADILY (ESPECIALLY OVER THE W FACING
SLOPES OF THE SAN JUANS (AREAS S OF WOLF CREEK PASS)...BUT THE RATES
WILL DECREASE. OVER THE PLAINS...IT WILL BE COOL. THERE WILL BE A
BETTER CHANCE OF SOME LIGHT PRECIP OVER THE LOWER ELEVATIONS AS THE
SHORT WAVE MOVES ACROSS THE STATE. THE PALMER DVD AREA WILL HAVE THE
OVERALL BEST CHANCE OF SNOW OVER THE PLAINS.
FOR FRI NITE INTO SAT...PRECIP WILL LIKELY BE MORE SHOWERY AS
ANOTHER SHORT WAVE MOVES ACROSS THE AREA DURING THE DAY SATURDAY.
BEST CHANCE WILL BE OVER THE CONTDVD REGION.
SUNDAY IS A BIT TRICKY...EC HAS IT DRY WHILE GFS HAS ANOTHER
DISTURBANCE TRANSLATING EASTWARD TO OUR SOUTH. FOR NOW KEPT THE N
PART OF THE CWA DRY WITH A SLIGHT CHANCE OF SOME LIGHT PRECIP OVER
THE S TIER. THIS DISCREPANCY IN MODEL GUIDANCE IS ASSOCIATED WITH
THE SPEEDS AND STRENGTH OF THE SHORTWAVES...WITH THE EC BEING A BIT
FASTER THAN THE GFS.
ANOTHER STRONG SHORT WAVE WILL MOVE ACROSS THE SW CONUS DURING THE
DAY TUESDAY. HOWEVER TRENDS IN THE GUIDANCE HAVE BEEN SHIFTING THIS
DISTURBANCE A BIT FARTHER SOUTH. AT THIS TIME THE BEST CHANCE OF ANY
PRECIP WILL BE OVER THE S1/2 OF THE CWA...MAINLY S OF HIGHWAY 50.
FOR NOW HAVE PAINTED SLIGHT POPS OVER THE REGION DURING THE MON-TUE
TIME FRAME. TEMPS WILL REMAIN BELOW AVERAGE.
OVERALL DURING THIS LONG TERM FCST PERIOD...TEMPS WILL BELOW NORMAL
EACH DAY OVER THE PLAINS. HODANISH
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1003 PM MST WED JAN 29 2014
STRONG JET STREAM OVER COLORADO WILL LEAD TO INCREASINGLY HEAVY
SNOW ALONG THE CONTINENTAL DIVIDE WITH WIDESPREAD IFR TO LIFR
CONDITIONS IN SN BLSN AND MTN OBSCURATIONS. THE SOUTHEAST MOUNTAINS
WILL REMAIN VFR BUT WITH SUBSTANTIAL TURBULENCE ALOFT AND POCKETS
OF LLWS ALONG THE LEE OF PIKES PEAK...SANGRES...AND WET MOUNTAINS.
LLWS SHOULD STAY ALONG/WEST OF I-25...AND HAVE THIS IN THE TAF FOR
KCOS THROUGH 13Z. CIGS WILL START TO LOWER AT KCOS DURING THE DAY
TOMORROW WITH MVFR TO IFR CIGS/VIS IN -SN AND BR TOWARDS 00Z. WILL
LIKELY SEE LIFR CONDITIONS DEVELOP AT KCOS AFTER 06Z BUT THIS IS
JUST BEYOND THE TAF PERIOD. COULD SEE AN INCH OF SNOW FALL AT THE
KCOS TERMINAL THROUGH THURSDAY NIGHT. KPUB WILL SEE CIGS DROP
INTO THE MVFR CATEGORY BY THURS EVENING...AND COULD SEE IFR
CONDITIONS DEVELOP BY EARLY FRIDAY MORNING...THOUGH ANY SNOW
APPEARS TO STAY TO THE NORTH AND WEST OF THE TERMINAL. KALS WILL
REMAIN VFR THROUGH THURSDAY WITH A PERIOD OF GUSTY AFTERNOON
WINDS. -KT
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING UNTIL 5 PM MST FRIDAY FOR COZ058>061.
HIGH WIND WARNING UNTIL 11 AM MST THURSDAY FOR COZ073>075-080-
082-087.
WINTER WEATHER ADVISORY FROM 5 AM THURSDAY TO 5 PM MST FRIDAY
FOR COZ064-066-067.
WINTER STORM WARNING FROM 5 AM THURSDAY TO 5 PM MST FRIDAY FOR
COZ068.
WINTER WEATHER ADVISORY UNTIL 5 AM MST FRIDAY FOR COZ062-063.
HIGH WIND WARNING UNTIL 5 AM MST THURSDAY FOR COZ081-084-085.
&&
$$
UPDATE...KT
SHORT TERM...MW
LONG TERM...HODANISH
AVIATION...KT
AREA FORECAST DISCUSSION
NWS ALBANY NY
1235 AM EST THU JAN 30 2014
.SYNOPSIS...
HIGH PRESSURE WILL CREST TO OUR SOUTH TONIGHT...BEFORE SLIDING OFF
THE NEW ENGLAND COAST ON THURSDAY. AFTER A COLD START TO THE DAY
THURSDAY...A RETURN SOUTHERLY FLOW WILL RESULT IN TEMPERATURES
MODERATING TO NEAR NORMAL. A WEAK DISTURBANCE WILL MOVE ACROSS THE
AREA ON FRIDAY...BRINGING JUST A FEW LIGHT SNOW SHOWERS OR FLURRIES
WITH EVEN WARMER TEMPERATURES. MORE UNSETTLED WEATHER IS POSSIBLE
FOR THE UPCOMING WEEKEND...ALTHOUGH DETAILS ARE NOT CERTAIN AT THIS
TIME.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1230 AM EST...THE LATEST RUC SHOWS A SHORT-WAVE MOVING ACROSS
SRN QUEBEC...NRN NY AND NRN NEW ENGLAND. THE WINDS HAVE ACTUALLY
INCREASED OVER PARTS OF THE REGION...AND TEMPS HAVE RISEN 2 TO 5
DEGREES. HAVE INCREASED MINS SLIGHTLY FROM THE PREVIOUS FCST. A
LAKE EFFECT BAND CONTINUES TO SCRAPE EXTREME NRN HERKIMER COUNTY
PER THE KTYX RADAR. AN INCH OR TWO IS POSSIBLE NORTH OF OLD
FORGE...AND A COATING TO AN INCH NEAR OLD FORGE. THE BAND SHOULD
CRUMBLE PRIOR TO 11Z WITH DRIER AIR...INCREASED SHEAR...AND A
LOWERING SUBSIDENCE INVERSION. OVERALL...ANOTHER COLD MORNING WITH
LOWS ZERO TO 5 BELOW OVER THE NORTH OF THE CAPITAL REGION...AND
SINGLE DIGITS FROM THE CAPITAL REGION SOUTH AND EAST.
DISCUSSION OF LAKE EFFECT EVOLUTION FOLLOWS...
MAIN ATTENTION HAS BEEN THE LAKE EFFECT SNOW DOWNWIND OF LAKE
ONTARIO. CSTAR INLAND EXTENT HAS BEEN PERFORMING OUTSTANDING WITH
THE LIMITS AROUND 55 MILES WHICH PLACES THE BAND RIGHT NEAR THE
NORTHERN HERKIMER COUNTY LINE. AS SEEN IN THE H2O VAPOR
IMAGERY...A SMALL SHORT WAVE WAS MOVING ACROSS WESTERN LAKE
ONTARIO AS THIS MAY TEMPORARILY RAISE THE INVERSION LEVEL /WHICH
WAS CAPTURED IN THE BUF 00Z SOUNDING/ FOR THE BAND TO MOVE A
LITTLE FURTHER INLAND AS SUGGESTED BY WRF/HRRR EXPERIMENTAL
REFLECTIVITIES AND RUC13 LOW LEVEL CONVERGENCE FIELDS AND
ASSOCIATED QPF. SO WE WILL INCREASE POPS AND ACCUMULATIONS FOR
NORTHERN HERKIMER COUNTY UP TO 2 INCHES FOR WESTERN PORTIONS OF
THE COUNTY /IN THE VICINITY OF MOSHIER FALLS/ PER THE CARIBOU SNOW
ACCUMULATION TECHNIQUE.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH FRIDAY NIGHT/...
DRY AND TRANQUIL CONDITIONS ARE EXPECTED THURSDAY WITH THE START OF
A WARMING TREND DUE TO A DEVELOPING SOUTHERLY FLOW. COMBINED WITH
AMPLE SUNSHINE...MOST AREAS SHOULD REACH THE WELL INTO THE 20S
DESPITE THE COLD START.
MAINLY DRY WEATHER SHOULD PERSIST THROUGH MUCH OF THURSDAY
NIGHT...ALTHOUGH AN UPPER LEVEL DISTURBANCE AND WEAKENING COLD FRONT
WILL APPROACH FROM THE GREAT LAKES. THERE COULD BE ENOUGH LIFT FOR A
FEW LIGHT SNOW SHOWERS BEFORE SUNRISE FRIDAY ACROSS THE WESTERN
MOHAWK VALLEY AND WESTERN ADIRONDACKS MAINLY DUE TO SOUTHERLY
UPSLOPE. THIS DISTURBANCE WILL CONTINUE TO WEAKEN...WITH ONLY A
SUBTLE SURFACE TROUGH MEANDERING ACROSS THE AREA ON FRIDAY. WILL
MENTION SLIGHT CHANCE TO CHANCE POPS WITH THE HIGHER VALUES WEST OF
THE HUDSON VALLEY. DESPITE MOSTLY CLOUDY SKIES...TEMPERATURES SHOULD
CONTINUE TO MODERATE INTO THE 30S IN VALLEY LOCATIONS WITH A
SOUTHWEST BREEZE DEVELOPING.
NOT MUCH IN THE WAY OF ANY DISCERNIBLE FORCING SEEN FOR FRIDAY
NIGHT...SO ONLY SLIGHT CHANCE POPS ACROSS THE AREA. TEMPERATURES
SHOULD BE ABOVE NORMAL WITH GENERALLY CLOUDY SKIES AND A LIGHT
SOUTHERLY BREEZE.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
UNSETTLED CONDITIONS EXPECTED THROUGH THE WEEKEND WITH SOME
IMPROVEMENTS FOR EARLY NEXT WEEK...BEFORE ANOTHER POTENTIAL SYSTEM
IMPACTING THE REGION AFTER THE LONG RANGE PERIOD.
LATEST NCEP MODEL SUITE AND INTERNATIONAL GUIDANCE ARE IN RATHER
GOOD AGREEMENT WITH SYNOPTIC PATTERN SETTING UP FOR THE UPCOMING
WEEKEND. ELONGATED TROUGH AXIS OVER THE WESTERN NOAM AND TIGHTENING
BAROCLINIC ZONE OVER THE CENTER OF THE NATION WILL AID IN A
DEVELOPMENT OF OVERRUNNING AND SURFACE WAVE DEVELOPMENT. THE
CONSENSUS FAVORS A SURFACE LOW TRACK TO BE WEST AND NORTH OF THE
REGION...HOWEVER...NEAR SURFACE TEMPERATURES WILL BE A CHALLENGE TO
DISLODGE THE ARCTIC AIR THAT HAS BEEN IN PLACE FOR SOME TIME. PER
THE THICKNESS MODIFIED SCHEMES...WE WILL LEAN A LITTLE COLDER WITH A
RAIN/SNOW MIXTURE BUT CAN NOT RULE OUT A PERIOD OF FREEZING RAIN
WITHIN THE ONSET OF PRECIPITATION. THE HEAVIER QPF IS EXPECTED TO
REMAIN WEST AND NORTH OF THE CAPITAL REGION SATURDAY THROUGH
SATURDAY NIGHT.
SUNDAY...SEEMS THE ASSOCIATED FRONTAL BOUNDARY WILL SLIDE EAST OF
THE REGION IN THE MORNING WITH IMPROVING CONDITIONS FOR THE REGION.
SOME LAKE RESPONSE IS POSSIBLE DOWNWIND OF LAKE ONTARIO WHERE WE
WILL KEEP LOW CHANCE POPS AND CLOUDS IN THE FORECAST. H850 TEMPS
DROP BACK TO BELOW -10C. SURFACE ANTICYCLONIC RIDGE AXIS IS EXPECTED
TO CREST OVER THE WESTERN AND CENTRAL GREAT LAKES REGION LATER
SUNDAY TO REDUCE LAKE IMPACTS AND GRADUAL CLEARING SKIES.
THIS SURFACE HIGH IS FORECAST TO STRENGTHEN AND BECOME ELONGATED
THROUGH EARLY NEXT WEEK BEFORE ANOTHER UPPER LOW MOVING ACROSS BAJA
CALIFORNIA AND TRACK ACROSS THE SOUTHERN PLAINS AND INTO THE
MISSISSIPPI VALLEY FOR THE MID WEEK PERIOD.
TEMPERATURES THROUGH THE PERIOD WILL AVERAGE NEAR NORMAL WITH
PRECIPITATION NEAR NORMAL.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
VFR CONDITIONS ARE EXPECTED AT ALL SITES THROUGH THE ENTIRE TAF
PERIOD ENDING AT 06Z FRIDAY.
SKIES WILL GENERALLY BE SKC OR FEW-SCT250 THROUGH THE ENTIRE TAF PERIOD.
WINDS WILL GENERALLY BE VARIABLE AT 7-8 KTS OVERNIGHT AND THEN
S-SW AT 4 TO 8 KTS ON THURSDAY BCMG LIGHT AND VARIABLE IN THE EVENING.
OUTLOOK...
THURSDAY TO THURSDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
FRIDAY TO FRIDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE
OF SHSN.
SATURDAY TO SUNDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF RA...SN.
SUNDAY NIGHT TO MONDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
NO WIDESPREAD HYDRO PROBLEMS ARE EXPECTED THROUGH THE NEXT FIVE DAYS.
MAINLY DRY CONDITIONS ARE FORECAST THROUGH THURSDAY...WITH JUST
ISOLATED TO SCATTERED LIGHT SNOW SHOWERS OR FLURRIES POSSIBLE LATE
THURSDAY NIGHT THROUGH FRIDAY. SOME ADDITIONAL SNOW OR EVEN RAIN
SHOWERS ARE POSSIBLE SATURDAY INTO SUNDAY AS TEMPERATURES MODERATE.
THIS PRECIPITATION LOOKS TO BE LIGHT AND WILL HAVE LITTLE EFFECT ON
AREA RIVERS AND STREAMS.
COLD TEMPERATURES WILL CONTINUE INTO THURSDAY...THEN FINALLY START
TO MODERATE FRIDAY AND ESPECIALLY INTO THE WEEKEND.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...JPV/WASULA
NEAR TERM...BGM/JPV/WASULA
SHORT TERM...JPV
LONG TERM...BGM
AVIATION...11
HYDROLOGY...11/JPV
AREA FORECAST DISCUSSION
NWS ALBANY NY
1231 AM EST THU JAN 30 2014
.SYNOPSIS...
HIGH PRESSURE WILL CREST TO OUR SOUTH TONIGHT...BEFORE SLIDING OFF
THE NEW ENGLAND COAST ON THURSDAY. AFTER A COLD START TO THE DAY
THURSDAY...A RETURN SOUTHERLY FLOW WILL RESULT IN TEMPERATURES
MODERATING TO NEAR NORMAL. A WEAK DISTURBANCE WILL MOVE ACROSS THE
AREA ON FRIDAY...BRINGING JUST A FEW LIGHT SNOW SHOWERS OR FLURRIES
WITH EVEN WARMER TEMPERATURES. MORE UNSETTLED WEATHER IS POSSIBLE
FOR THE UPCOMING WEEKEND...ALTHOUGH DETAILS ARE NOT CERTAIN AT THIS
TIME.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1230 AM EST...THE LATEST RUC SHOWS A SHORT-WAVE MOVING ACROSS
SRN QUEBEC...NRN NY AND NRN NEW ENGLAND. THE WINDS HAVE ACTUALLY
INCREASED OVER PARTS OF THE REGION...AND TEMPS HAVE RISEN 2 TO 5
DEGREES. HAVE INCREASED MINS SLIGHTLY FROM THE PREVIOUS FCST. A
LAKE EFFECT BAND CONTINUES TO SCRAPE EXTREME NRN HERKIMER COUNTY
PER THE KTYX RADAR. AN INCH OR TWO IS POSSIBLE NORTH OF OLD
FORGE...AND A COATING TO AN INCH NEAR OLD FORGE. THE BAND SHOULD
CRUMBLE PRIOR TO 11Z WITH DRIER AIR...INCREASED SHEAR...AND A
LOWERING SUBSIDENCE INVERSION. OVERALL...ANOTHER COLD MORNING WITH
LOWS ZERO TO 5 BELOW OVER THE NORTH OF THE CAPITAL REGION...AND
SINGLE DIGITS FROM THE CAPITAL REGION SOUTH AND EAST.
DISCUSSION OF LAKE EFFECT EVOLUTION FOLLOWS...
MAIN ATTENTION HAS BEEN THE LAKE EFFECT SNOW DOWNWIND OF LAKE
ONTARIO. CSTAR INLAND EXTENT HAS BEEN PERFORMING OUTSTANDING WITH
THE LIMITS AROUND 55 MILES WHICH PLACES THE BAND RIGHT NEAR THE
NORTHERN HERKIMER COUNTY LINE. AS SEEN IN THE H2O VAPOR
IMAGERY...A SMALL SHORT WAVE WAS MOVING ACROSS WESTERN LAKE
ONTARIO AS THIS MAY TEMPORARILY RAISE THE INVERSION LEVEL /WHICH
WAS CAPTURED IN THE BUF 00Z SOUNDING/ FOR THE BAND TO MOVE A
LITTLE FURTHER INLAND AS SUGGESTED BY WRF/HRRR EXPERIMENTAL
REFLECTIVITIES AND RUC13 LOW LEVEL CONVERGENCE FIELDS AND
ASSOCIATED QPF. SO WE WILL INCREASE POPS AND ACCUMULATIONS FOR
NORTHERN HERKIMER COUNTY UP TO 2 INCHES FOR WESTERN PORTIONS OF
THE COUNTY /IN THE VICINITY OF MOSHIER FALLS/ PER THE CARIBOU SNOW
ACCUMULATION TECHNIQUE.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH FRIDAY NIGHT/...
DRY AND TRANQUIL CONDITIONS ARE EXPECTED THURSDAY WITH THE START OF
A WARMING TREND DUE TO A DEVELOPING SOUTHERLY FLOW. COMBINED WITH
AMPLE SUNSHINE...MOST AREAS SHOULD REACH THE WELL INTO THE 20S
DESPITE THE COLD START.
MAINLY DRY WEATHER SHOULD PERSIST THROUGH MUCH OF THURSDAY
NIGHT...ALTHOUGH AN UPPER LEVEL DISTURBANCE AND WEAKENING COLD FRONT
WILL APPROACH FROM THE GREAT LAKES. THERE COULD BE ENOUGH LIFT FOR A
FEW LIGHT SNOW SHOWERS BEFORE SUNRISE FRIDAY ACROSS THE WESTERN
MOHAWK VALLEY AND WESTERN ADIRONDACKS MAINLY DUE TO SOUTHERLY
UPSLOPE. THIS DISTURBANCE WILL CONTINUE TO WEAKEN...WITH ONLY A
SUBTLE SURFACE TROUGH MEANDERING ACROSS THE AREA ON FRIDAY. WILL
MENTION SLIGHT CHANCE TO CHANCE POPS WITH THE HIGHER VALUES WEST OF
THE HUDSON VALLEY. DESPITE MOSTLY CLOUDY SKIES...TEMPERATURES SHOULD
CONTINUE TO MODERATE INTO THE 30S IN VALLEY LOCATIONS WITH A
SOUTHWEST BREEZE DEVELOPING.
NOT MUCH IN THE WAY OF ANY DISCERNIBLE FORCING SEEN FOR FRIDAY
NIGHT...SO ONLY SLIGHT CHANCE POPS ACROSS THE AREA. TEMPERATURES
SHOULD BE ABOVE NORMAL WITH GENERALLY CLOUDY SKIES AND A LIGHT
SOUTHERLY BREEZE.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
UNSETTLED CONDITIONS EXPECTED THROUGH THE WEEKEND WITH SOME
IMPROVEMENTS FOR EARLY NEXT WEEK...BEFORE ANOTHER POTENTIAL SYSTEM
IMPACTING THE REGION AFTER THE LONG RANGE PERIOD.
LATEST NCEP MODEL SUITE AND INTERNATIONAL GUIDANCE ARE IN RATHER
GOOD AGREEMENT WITH SYNOPTIC PATTERN SETTING UP FOR THE UPCOMING
WEEKEND. ELONGATED TROUGH AXIS OVER THE WESTERN NOAM AND TIGHTENING
BAROCLINIC ZONE OVER THE CENTER OF THE NATION WILL AID IN A
DEVELOPMENT OF OVERRUNNING AND SURFACE WAVE DEVELOPMENT. THE
CONSENSUS FAVORS A SURFACE LOW TRACK TO BE WEST AND NORTH OF THE
REGION...HOWEVER...NEAR SURFACE TEMPERATURES WILL BE A CHALLENGE TO
DISLODGE THE ARCTIC AIR THAT HAS BEEN IN PLACE FOR SOME TIME. PER
THE THICKNESS MODIFIED SCHEMES...WE WILL LEAN A LITTLE COLDER WITH A
RAIN/SNOW MIXTURE BUT CAN NOT RULE OUT A PERIOD OF FREEZING RAIN
WITHIN THE ONSET OF PRECIPITATION. THE HEAVIER QPF IS EXPECTED TO
REMAIN WEST AND NORTH OF THE CAPITAL REGION SATURDAY THROUGH
SATURDAY NIGHT.
SUNDAY...SEEMS THE ASSOCIATED FRONTAL BOUNDARY WILL SLIDE EAST OF
THE REGION IN THE MORNING WITH IMPROVING CONDITIONS FOR THE REGION.
SOME LAKE RESPONSE IS POSSIBLE DOWNWIND OF LAKE ONTARIO WHERE WE
WILL KEEP LOW CHANCE POPS AND CLOUDS IN THE FORECAST. H850 TEMPS
DROP BACK TO BELOW -10C. SURFACE ANTICYCLONIC RIDGE AXIS IS EXPECTED
TO CREST OVER THE WESTERN AND CENTRAL GREAT LAKES REGION LATER
SUNDAY TO REDUCE LAKE IMPACTS AND GRADUAL CLEARING SKIES.
THIS SURFACE HIGH IS FORECAST TO STRENGTHEN AND BECOME ELONGATED
THROUGH EARLY NEXT WEEK BEFORE ANOTHER UPPER LOW MOVING ACROSS BAJA
CALIFORNIA AND TRACK ACROSS THE SOUTHERN PLAINS AND INTO THE
MISSISSIPPI VALLEY FOR THE MID WEEK PERIOD.
TEMPERATURES THROUGH THE PERIOD WILL AVERAGE NEAR NORMAL WITH
PRECIPITATION NEAR NORMAL.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
VFR CONDITIONS ARE EXPECTED AT ALL SITES THROUGH THE ENTIRE TAF
PERIOD.
OUTSIDE OF SOME CU/SC OFF LAKE ONTARIO IMPACTING KGFL...NEAR IDEAL
FLIGHT CONDITIONS WITH NO AVIATION OBSTRUCTIONS EXPECTED. RIDGE
BUILDS IN ACROSS THE AREA TONIGHT INTO THURSDAY.
OUTLOOK...
THURSDAY TO THURSDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
FRIDAY TO FRIDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE
OF SHSN.
SATURDAY TO SUNDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF RA...SN.
SUNDAY NIGHT TO MONDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
NO WIDESPREAD HYDRO PROBLEMS ARE EXPECTED THROUGH THE NEXT FIVE DAYS.
MAINLY DRY CONDITIONS ARE FORECAST THROUGH THURSDAY...WITH JUST
ISOLATED TO SCATTERED LIGHT SNOW SHOWERS OR FLURRIES POSSIBLE LATE
THURSDAY NIGHT THROUGH FRIDAY. SOME ADDITIONAL SNOW OR EVEN RAIN
SHOWERS ARE POSSIBLE SATURDAY INTO SUNDAY AS TEMPERATURES MODERATE.
THIS PRECIPITATION LOOKS TO BE LIGHT AND WILL HAVE LITTLE EFFECT ON
AREA RIVERS AND STREAMS.
COLD TEMPERATURES WILL CONTINUE INTO THURSDAY...THEN FINALLY START
TO MODERATE FRIDAY AND ESPECIALLY INTO THE WEEKEND.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...JPV/WASULA
NEAR TERM...BGM/JPV/WASULA
SHORT TERM...JPV
LONG TERM...BGM
AVIATION...FRUGIS/BGM
HYDROLOGY...11/JPV
AREA FORECAST DISCUSSION...UPDATED
NWS TWIN CITIES/CHANHASSEN MN
1201 AM CST THU JAN 30 2014
.UPDATE...
ISSUED AT 836 PM CST WED JAN 29 2014
SIGNIFICANT UPDATES HAVE BEEN MADE TO THE FORECAST LATE TONIGHT
AND EARLY THURSDAY. SHORT TERM MODELS AND THE 00Z NAM HAVE COME
CONSIDERABLY FARTHER NORTH AND HAVE BECOME MORE INTENSE WITH THE
BAND OF SNOW. IT WILL BE A QUICK HITTING SYSTEM...BUT IT WILL BE
ACCOMPANIED BY VERY HEAVY SNOW DURING THE MORNING RUSH WHICH WILL
LIKELY BRING SEVERE IMPACTS.
THE LOW CURRENTLY IS LOCATED OVER SOUTHWESTERN SD AND WILL TRACK
ALONG THE SD/NE BORDER INTO SOUTHEASTERN MN BY MIDDAY THURSDAY.
THE SNOW IS CURRENTLY FALLING IN A RELATIVELY DATA SPARSE AREA OF
SOUTHEASTERN MT...BUT MILES CITY HAS REPORTED 1/2-3/4 MILE SNOW
FOR THE PAST FEW HOURS. AS THIS DISTURBANCE ROTATES EASTWARD...THE
700 MB TROUGH WILL DEEPEN OVER MN AT 12Z AND CONTINUE TO DO SO
OVER WI BY 18Z. DEEP OMEGA WITHIN THE DGZ AND A FAIRLY HIGH AMOUNT
OF MOISTURE FOR LATE JANUARY WITH PW VALUES OF AROUND 0.4 INCHES
/ABOVE THE 75TH PERCENTILE/...SHOULD WORK TO PRODUCE VERY INTENSE
SNOW RATES AT TIMES. THESE SNOW RATES COULD REACH 1-2 INCHES PER
HOUR DURING THE HEIGHT OF THE EVENT...SURE TO WREAK HAVOC WITH THE
MORNING COMMUTE. THE HOPWRF...HRRR...AND RAP ALL GENERALLY AGREE
WITH THE LOCATION/AXIS OF HEAVY SNOW STRETCHING FROM GLENCOE TO
THE TWIN CITIES AND RICE LAKE. NEW 00Z NAM HAS COME INTO LINE WITH
THIS IDEA AS WELL SO CONFIDENCE HAS INCREASED ENOUGH TO POST A
WARNING ALONG THIS AXIS AND AN ADVISORY ELSEWHERE. FUTURE
ADJUSTMENTS MAY BE NECESSARY AS THE REST OF THE 00Z MODEL SUITE
IS GENERATED.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 249 PM CST WED JAN 29 2014
ACCUMULATING SNOW EXPECTED TO BEGIN OVERNIGHT ACROSS THE
SOUTHWESTERN MINNESOTA AND MOVE WEST TO EAST ACROSS THE REMAINDER OF
SOUTHERN MINNESOTA AND WESTERN WISCONSIN DURING THE MORNING
TOMORROW. THE MORNING COMMUTE WILL BE HEAVILY IMPACTED...AS THE
HEAVIEST SNOW LOOKS TO REACH THE METRO FROM ROUGHLY 6AM-9AM. A
WINTER WEATHER ADVISORY WAS POSTED AFTER COLLABORATION WITH ARX AND
DMX...WITH THE HEAVIEST SNOW AMOUNTS EXPECTED IN IN THE ARX CWA.
STILL...ALBERT LEA THROUGH RED WIND...AND OVER TO EAU CLAIRE ARE
EXPECTED TO SEE ROUGHLY 3-4 INCHES OF SNOW...WHICH WILL BE HEAVY AT
TIMES DURING THE PEAK TRAVEL TIME THURSDAY MORNING. THE 29.12 RUN
OF THE ECMWF INCREASED QPF TO THE NORTH AND BETTER MATCHES THE NCEP
MODELS. PREVIOUS FORECAST LOOKED VERY GOOD...SO ONLY MINOR TWEAKS
WERE MADE...MAINLY TO THE TIMING WHICH DELAYED THE ONSET OF THE SNOW
BY ABOUT TWO HOURS. UPPER LEVEL DYNAMICS LOOK GOOD TOMORROW MORNING
ACROSS THE AREA...WITH THE BEST UPPER LEVEL FORCING MOVING ACROSS
SOUTHERN MN OVERNIGHT AND INCREASING OVER SOUTHEASTERN MN INTO
WESTERN WI. THE GOING FORECAST CALLS FOR THE HIGHEST AMOUNTS IN
THIS AREA...PRIMARILY FALLING FROM 12Z TO 18Z TOMORROW. THE LIFT
STILL LOOKS GOOD ON THE 295K SURFACE AS THE STRONG UPGLIDE BEGINS TO
COINCIDE WITH A SATURATED ENVIRONMENT BY 09Z ACROSS WESTERN MN. FOR
THE METRO...2"-3" STILL LOOKS ON TRACK ACROSS THE SOUTHERN PORTION...WITH
CLOSER TO 1"-2" ACROSS THE NORTH. WINDS WILL TURN NORTHWEST AND
GET BLUSTERY TOMORROW AFTERNOON AS THE SNOW MACHINE SHUTS OFF.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 249 PM CST WED JAN 29 2014
LONGER TERM TRENDS CHANGE LITTLE AS FAR AS THE UPPER LEVEL FLOW
PATTERN ACROSS THE NORTHERN TIER STATES. WE REMAIN LOCKED IN THE
COLDER THAN NORMAL REGIME THROUGH THIS FORECAST PERIOD. SEVERAL
ARCTIC COLD FRONTS SWEEP ACROSS THE REGION. THE FIRST EXITS THE
AREA THURSDAY NIGHT. THIS MAY GENERATE WIND CHILL ADVISORY
CRITERIA OVER MUCH OF THE REGION SPREADING FROM WEST TO EAST BY
FRIDAY MORNING.
THEN ON SATURDAY....THE FRONT MOVES THROUGH AND THIS WILL BRING A
SMALL CHANCE OF LIGHT SNOW TO THE SOUTH AND EAST PORTION OF THE
AREA. MOISTURE WILL BE LACKING WITH THE SYSTEM...BUT MAY STILL
MUSTER ENOUGH TO GENERATE SOME LIGHT SNOW. MOST DETERMINISTIC
MODELS CONTINUE TO SHOW SOME LIGHTER QPF IN EASTERN AREA...WITH
THE GFS ENSEMBLES SHOWING TH MAIN FOCUS MORE TO THE FAR SOUTHERN
MN DURING THE PERIOD.
COLDER AIR FOLLOWS THIS SYSTEM...BUT NOT AS COLD AS PREVIOUS
SYSTEMS. USED BIAS CORRECTED TEMPERATURES FOR NOW...AS WE HAVE BEEN
RUNNING A BIT COLD OF LATE IN VERIFICATION WITH THESE COLD AIR
INTRUSIONS. VERY LITTLE SNOW COVER TO THE SOUTH AND WEST OF
MINNESOTA...SO THERE IS OPPORTUNITY TO WARM A BIT MORE SIGNIFICANTLY
AHEAD OF EAST OF THE FRONTS. WILL CONTINUE THIS TREND FOR NEXT
MONDAY AS WELL...WITH PERHAPS A MORE SIGNIFICANT COLD AIR SURGE
COMING TOWARD MIDWEEK NEXT WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1150 PM CST WED JAN 29 2014
THE CONFIDENCE IN A PERIOD OF MDT-HVY SNOW THURSDAY MORNING IS
VERY HIGH. NOT MUCH HAS CHANGED WITH THE 06Z TAFS WITH TIMING
GENERALLY THE SAME FROM THE PREVIOUS TAFS. THE SNOW WILL ARRIVE
BETWEEN 09-12Z AND QUICKLY BECOME MODERATE OR HEAVY DURING THE
MORNING COMMUTE FOR ALL OF THE TAF SITES. LIFR CONDS EXPECTED FOR
A PERIOD OF 3-4 HOURS UNTIL IMPROVING CONDITIONS BY LATE MORNING.
TOTAL ACCUMS OF 3-6 INCHES APPEAR LIKELY WITH HOURLY RATES AS HIGH
AS 1-2 INCHES POSSIBLE. UNTIL THE SNOW ARRIVES...VFR CONDITIONS
EXPECTED. VFR CONDITIONS ARE ALSO EXPECTED SHORTLY AFTER THE SNOW
ENDS.
KMSP...THE SNOW WILL ARRIVE SOMETIME AROUND 11Z LATE TONIGHT AND
QUICKLY BECOME HEAVY SHORTLY THEREAFTER UNTIL ABOUT 16Z.
CONFIDENCE IS VERY HIGH THAT AT LEAST A FEW INCHES WILL FALL ON
THE TERMINAL DURING THIS TIME.
/OUTLOOK FOR KMSP/
FRI...VFR. WINDS WSW 5 KTS.
SAT...VFR. WINDS SW 5KTS EARLY BCMG NW AT 10G15KTS.
SUN...VFR. WINDS W BECOMING SW 5-10 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...WINTER WEATHER ADVISORY FROM 5 AM TO NOON CST THURSDAY FOR
MNZ044-045-067-074>078-082>085-091>093.
WINTER WEATHER ADVISORY UNTIL NOON CST THURSDAY FOR MNZ041>043-
047>050-054>058-064-065-073.
WINTER STORM WARNING FROM 5 AM TO NOON CST THURSDAY FOR
MNZ051>053-059>063-066-068>070.
WI...WINTER WEATHER ADVISORY FROM 5 AM TO NOON CST THURSDAY FOR
WIZ026-028.
WINTER STORM WARNING FROM 5 AM TO NOON CST THURSDAY FOR
WIZ014>016-023>025-027.
&&
$$
UPDATE...BORGHOFF
SHORT TERM...SPD
LONG TERM...DWE
AVIATION...BORGHOFF
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1138 PM CST WED JAN 29 2014
.SHORT TERM...(TONIGHT THROUGH THURSDAY EVENING)
ISSUED AT 1137 PM CST WED JAN 29 2014
REST OF THE NIGHT: CLOUDY AND MILD. BREEZY E OF HWY 183. S WINDS
WILL GUST UP TO 32 KTS AT TIMES.
CLOUDS/LOW TEMPS/WINDS AND WIND GUSTS HAVE ALL BEEN INCREASED FROM
THE PREVIOUS FCST.
THE COLD FRONT IS OVER SRN SD AND NEARING THE NEB BORDER AT 05Z.
ITS PASSAGE WILL BE ABOUT 3 HRS SLOWER THAN EXPECTED 24 HRS AGO.
THE 03Z RAP SUGGESTS IT WILL BE NEARING I-80 AT DAYBREAK AND TO THE
NEB-KS BORDER BY 15Z.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 408 PM CST WED JAN 29 2014
MAIN FORECAST CONCERNS WILL BE CHANCES FOR SNOW LATE THIS WEEK AND
EARLY NEXT WEEK AND TEMPERATURES THROUGH THE PERIOD.
AN UPPER LEVEL WAVE WILL MOVE INTO THE AREA THURSDAY NIGHT. MODELS
ARE FAIRLY SIMILAR IN BRINGING THE WAVE INTO THE AREA DURING THE
EVENING AND SPREADING PRECIPITATION INTO THE FORECAST AREA DURING
THE EVENING...THEN ACROSS THE ENTIRE AREA LATE THURSDAY NIGHT. THE
PRECIPITATION WILL LINGER INTO FRIDAY MORNING...BUT THE MODELS ALL
INDICATE THAT THERE WILL BE A LULL DURING THE AFTERNOON. THEN AS
ANOTHER UPPER LEVEL WAVE MOVES INTO THE AREA PRECIPITATION INCREASES
AGAIN FOR FRIDAY NIGHT. HAVE LEANED TOWARDS LIGHTER PRECIPITATION
DURING THE AFTERNOON. THIS HAS CHANGED THE AMOUNTS OF SNOW FOR THE
AREA. AT THIS TIME THE WEST LOOKS TO BE THE GREATEST RECIPIENT OF
THE THURSDAY NIGHT INTO FRIDAY MORNING PRECIPITATION WHILE THE SOUTH
LOOKS TO BE THE MOST LIKELY AREA FOR FRIDAY NIGHT. PRECIPITATION
TYPE SHOULD BE ALL SNOW. TEMPERATURES WILL BE COOLER THAN NORMAL IN
THE TEENS FOR LOWS AND 20S FOR HIGHS.
A SURFACE HIGH PRESSURE SYSTEM SETTLES INTO THE AREA ON SATURDAY AND
MOVES TO THE EAST ON SUNDAY AND MONDAY. NORMALLY THIS WOULD BRING
SOME COOLER TEMPERATURES ON SATURDAY THEN WARMER ON SUNDAY...BUT
TEMPERATURES WILL CONTINUE ON THE COOLER SIDE OF NORMAL.
ANOTHER UPPER LEVEL WAVE WILL APPROACH THE AREA MONDAY NIGHT INTO
TUESDAY. MODELS HAVE A FEW DIFFERENCES WITH THIS WAVE. THE GFS HAS
MORE OF AN OPEN WAVE THAT MOVES THROUGH THE CENTRAL PLAINS A LITTLE
QUICKER THAN THE ECMWF THAT HAS MORE OF A CLOSED LOW THAT MOVES
THROUGH THE SOUTHERN PLAINS A LITTLE SLOWER. EITHER WAY HAVE KEPT
SOME SNOW CHANCES IN FOR MONDAY NIGHT INTO TUESDAY WITH THE BEST
CHANCES IN THE SOUTHERN PART OF THE FORECAST AREA. TEMPERATURES WILL
CONTINUE ON THE COOLER SIDE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1137 PM CST WED JAN 29 2014
REST OF THE NIGHT: VFR CIGS AROUND 10K FT. SSW WINDS WILL GUST UP
TO 32 KTS. LLWS WILL BE SIGNIFICANT THRU 09Z WITH THE 50 KTS AS
LOW AS 1K FT. A COLD FRONTAL PASSAGE WILL DECREASE WINDS AROUND
10Z WITH A WSHFT TO WSW. CONFIDENCE: HIGH
THU: VFR CIGS AROUND 15K FT. SOME 2500 FT STRATOCU MAY FORM FOR A
TIME...ESPECIALLY 14Z-18Z. WINDS WILL BECOME NNW AND WILL GUST
24-34 KTS. WINDS DIMINISH LATE IN THE AFTERNOON AND SHIFT TO NNE.
CONFIDENCE: HIGH
THU EVE: VFR CIGS LOWER TO AROUND 5K FT BY 05Z. IFR -SN IS
EXPECTED TO MOVE IN...BUT THERE IS UNCERTAINTY ON TIMING. NNE
WINDS AROUND 10 KTS. CONFIDENCE: MEDIUM
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...HALBLAUB
LONG TERM...JCB
AVIATION...HALBLAUB
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1126 PM CST WED JAN 29 2014
.UPDATE...
ISSUED AT 840 PM CST WED JAN 29 2014
00Z UPPER AIR ANALYSIS INDICATED A POTENT WAVE ENTERING THE
PACIFIC NORTHWEST...WITH A 160 KNOT JET AT 300 MB AND 150M HEIGHT
FALLS AT 500. SURFACE LOW PRESSURE ACROSS THE SD/NE/WY BORDER
REGION WILL CONTINUE TO MOVE ALMOST DUE EAST TONIGHT AS THIS WAVE
CONTINUES TO CROSS THE ROCKIES. NEW 00Z NAM AND LATEST SEVERAL
ROUNDS OF THE RAP ALL SUGGEST THAT THE BULK OF THE PRECIP WILL
REMAIN ACROSS SOUTH DAKOTA...WITH JUST A GLANCING BLOW ALONG THE
NE/SD BORDER THROUGH THE NIGHT. INITIALLY...IT WILL PROBABLY JUST
BE RAIN AS TEMPS AHEAD OF THE LOW REMAIN QUITE MILD IN THE UPPER
30S. STILL COULD BE MIXED WINTRY PRECIPITATION...BUT ALSO AM
THINKING PRECIP MAY EVEN MOVE OUT BEFORE THE COLDER AIR MOVES IN.
EITHER WAY...IT`S NOT A VERY BIG SYSTEM FOR OUR AREA WITH FAIRLY
LOW POPS EXPECTED. MODELS DO SUGGEST THAT THE TRAILING END OF THE
COLD FRONT COULD SEE SOME MOISTURE INCREASE BY MID TO LATE
MORNING...SO WOULD NOT BE SURPRISED TO SEE SOME SPOTTY PRECIP
DEVELOP IN SOUTHEAST NEBRASKA THURSDAY MORNING...BUT PUSHING
SOUTHEAST OF THE AREA BY NOON.
&&
.SHORT TERM...(TONIGHT THROUGH SATURDAY)
ISSUED AT 307 PM CST WED JAN 29 2014
EARLY AFTERNOON WATER VAPOR IMAGERY INDICATED A SHORTWAVE TROUGH
MOVING THROUGH WA. THIS SYSTEM WAS ASSOCIATED WITH A 120 KT H25
JET AND 130 M H5 HEIGHT FALLS. THIS SYSTEM WILL MOVE INTO THE
NORTHERN PLAINS TONIGHT AND ALLOW FOR A COLD FRONT TO SWEEP
THROUGH THE FA ON TUESDAY. AHEAD OF THE SYSTEM WE SHOULD CONTINUE
TO SEE A WARM AND BREEZY EVENING AS LOW PRESSURE CONTINUES TO
DEEPEN OVER THE HIGH PLAINS. THIS LOW WILL TAKE A TRACK ALONG THE
SD/NEB BORDER OVERNIGHT AND INTO NORTHERN IA ON THU. AS PREVIOUSLY
NOTED MUCH OF THE LARGE-SCALE FORCING FOR ASCENT WILL GO NORTH OF
OUR FA OVER SD/MN ASSOCIATED WITH THIS SYSTEM. LOW TO MID LEVEL
FRONTOGENESIS WILL INCREASE AS THE LOW MOVES BY TONIGHT AND THIS
MAY STILL BE ENOUGH LIFT TO PRODUCE SOME LIGHT PRECIP OVER OUR
EXTREME NORTH...GENERALLY NORTH OF A LINE FROM AROUND NLG TO TQE
TO HNR. POINT FORECAST SOUNDINGS STILL INDICATE THAT A MIX OF
LIGHT PRECIP WILL BE POSSIBLE IF ANYTHING FALLS. WE ARE NOT
EXPECTING ANY ICE ACCUMULATION ANY ANY SNOWFALL WOULD BE A TENTH
OF AN INCH OF LESS.
A BREAK IN WEATHER SYSTEMS IS EXPECTED FOR MOST OF THURSDAY AS THE
LEAD SHORTWAVE TROUGH MOVES EAST AND THE NEXT SHORTWAVE ISN`T
EXPECTED UNTIL THURSDAY NIGHT. THIS SHORTWAVE TROUGH IS EXPECTED
TO MOVE ACROSS NEB/IA OVERNIGHT THU AND ACT ON THE PRE-EXISTING
THERMAL GRADIENT TO PRODUCE ENOUGH FRONTAL CIRCULATION FOR LIGHT
PRECIP. THE THERMAL PROFILE WOULD SUPPORT ALL SNOW BY THIS TIME.
ANY PRECIPITATION ASSOCIATED WITH THE THURSDAY NIGHT WAVE SHOULD
DISSIPATE BY FRI AFTERNOON AS THE CIRCULATION ENDS. AMOUNTS WILL
GENERALLY BE LIGHT AND MAINLY OVER THE SOUTHWEST 2/3RD OF THE
FA...BUT AMOUNTS AROUND AN INCH ARE NOT OUT OF THE QUESTION.
ANOTHER LITTLE BREAK IS EXPECTED IN THE LIFT IS EXPECTED FRI
AFTERNOON BEFORE A BIT STRONGER SHORTWAVE TROUGH IS EXPECTED FOR
FRIDAY NIGHT. THIS WILL CREATE A BIT STRONGER FRONTOGENESIS...HAVE
BETTER MOISTURE TO WORK WITH...AND STATIC STABILITY APPEARS
WEAKER. THUS A STRONGER FRONTAL CIRCULATION IS LIKELY TO DEVELOP
FRI NIGHT...ESPECIALLY IN THE SOUTHERN FA AND 1-2 INCHES APPEAR
POSSIBLE AT THIS TIME. THE NORTHEASTERN THIRD OF THE FA WILL
STRUGGLE THROUGH BOTH EVENTS TO ACCUMULATE SNOW DUE TO LOW LEVEL
DRY AIR BEING ADVECTED IN FROM THE NORTHEAST AND WILL HAVE THE
LOWEST SNOW TOTALS NORTHEAST OF A LINE FROM NORFOLK TO OMAHA TO
RED OAK. WE DID LINGER SOME POPS INTO SAT MORNING BEFORE THIS
SYSTEM EXITS TO THE EAST.
.LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 307 PM CST WED JAN 29 2014
AN UPPER LEVEL TROUGH WILL BE MOVING ACROSS THE SOUTHWESTERN
CONUS ALLOWING SOUTHWESTERLY FLOW OVER THE NATIONS MID SECTION AT
THE BEGINNING OF THE FORECAST PERIOD. THE BEGINNING OF THE PERIOD
WILL BE COOL AND DRY. THE NEXT CHANCE FOR SNOW WILL BE MONDAY
NIGHT INTO TUESDAY OVER THE SOUTHERN THIRD OF THE FORECAST AREA IN
ADVANCE OF A PIECE OF SHORTWAVE ENERGY MOVING NORTHEAST FROM THE
CENTRAL PLAINS. TEMPERATURES OVER THE TIME PERIOD LOOK TO BE
SLIGHTLY BELOW NORMAL WITH HIGHS IN THE TEENS AND 20S AND LOWS IN
THE SINGLE DIGITS TO MID TEENS.
&&
.AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1117 PM CST WED JAN 29 2014
WINDS WILL CONTINUE TO BE THE PRIMARY FORECAST CHALLENGE THROUGH
THE PERIOD. SOUTH SOUTHWEST WINDS AT 14 TO 18 KNOTS...WITH GUSTS
UP TO 25 KNOTS AT KOFK. THIS IS AHEAD OF A COLD FRONT THAT SHOULD
ARRIVE AT KOFK BY 13Z...KLNK BY 15Z AND KOMA BY 16Z WHEN WINDS
BECOME NORTHWEST. UNTIL THE FRONT ARRIVES...THERE WILL ALSO BE
CONVECTIVE NON LOW LEVEL WIND SHEAR AT ALL 3 TAF SITES WITH WINDS
AT 2000 FEET FROM ABOUT 220 DEGREES UP TO 60 KNOTS.
OTHERWISE...MID CLOUDS WILL BE MOST PREVALENT AND GENERALLY VFR
CONDITIONS...ALTHOUGH A COUPLE HOURS OF MVFR CLOUDS COULD OCCUR AT
KOFK WITH THE FRONTAL PASSAGE. A WINTRY MIX OF PRECIP MAY ALSO
DEVELOP IN THE VINCINITY OF KOFK 09-12Z...AND IN THE VICINITY OF
KOMA BY 12-15Z...BUT NOT CONFIDENT ENOUGH TO MENTION AT THE TAF
SITE. REGIONAL 88D RADARS ARE SHOWING SOME RETURNS MOVING INTO
NORTHEAST NEBRASKA...BUT THIS IS JUST WHERE THE RADAR BEAM IS
INTERSECTING THE CLOUD BASE AROUND 8000-10000 FEET AND VERY
DOUBTFUL THIS IS REACHING THE SURFACE SINCE IT`S SO DRY.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
UPDATE...DEWALD
SHORT TERM...BOUSTEAD
LONG TERM...KERN
AVIATION...DEWALD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
311 AM EST THU JAN 30 2014
.SYNOPSIS...MODIFIED ARCTIC HIGH PRESSURE WILL REMAIN OVER THE
CAROLINAS THROUGH THURSDAY.
&&
.NEAR TERM /TODAY AND TONIGHT/...
AS OF 255 AM THURSDAY...
...WINTER WEATHER ADVISORY FOR ICE/BLACK ICE WILL CONTINUE THROUGH
NOON...
...ANOTHER WINTER WEATHER ADVISORY FOR BLACK ICE MAY BE NEEDED FOR
PORTIONS OF CENTRAL NC TONIGHT/FRI MORNING...
OVERVIEW: PER THE LATEST WV IMAGERY AND RAP DATA...A SHORTWAVE
TROUGH CENTERED OVER EASTERN TN AT 06Z WILL DEAMPLIFY AS IT LIFTS
ENE TO THE DELMARVA/MID-ATLANTIC COAST BY 18Z...PROGRESSING OFFSHORE
INTO THE ATLANTIC THEREAFTER. ANOTHER SHORTWAVE TROUGH APPROACHING
THE TX/LA GULF COAST AT 06Z WILL DEAMPLIFY AS IT TRACKS ESE/SE INTO
THE GOMEX THIS AFT/EVE...THEN EAST TOWARD THE FL GULF COAST BY 12Z
FRI. WEAK DPVA ASSOCIATED WITH A SHEAR AXIS EXTENDING NORTHWARD FROM
THE AFOREMENTIONED SHORTWAVE WILL TRACK EAST THROUGH THE REGION TO
THE CAROLINA COAST TONIGHT. MODIFIED ARCTIC HIGH PRESSURE WILL
PERSIST ACROSS THE CAROLINAS TODAY. AN ELONGATED SFC TROUGH WILL
PERSIST OFFSHORE THE CAROLINA COAST...IN A REGION OF STRONG
BAROCLINICITY BETWEEN THE AFOREMENTIONED ARCTIC AIRMASS AND THE GULF
STREAM. WEAK CYCLOGENESIS WILL LIKELY OCCUR ALONG PORTIONS OF THE
OFFSHORE TROUGH /BAROCLINIC ZONE/ TODAY AND TONIGHT IN ASSOCIATION
WITH WEAK DPVA ATTENDANT THE AFOREMENTIONED UPPER LEVEL FEATURES.
PRECIPITATION CHANCES: A VERY DRY ARCTIC AIRMASS IS IN PLACE INLAND
ACROSS CENTRAL NC TODAY (00Z GSO RAOB/PWAT 0.05"). UPPER LEVEL
MOISTURE INCREASES TOWARD THE COAST PER THE 00Z MHX RAOB AND 06Z
IR/WV SAT IMAGERY...THOUGH EVEN THERE THE LOWEST 10-15 KFT REMAIN
EXCEEDINGLY DRY. LOW-LEVEL WARM ADVECTION WILL STRENGTHEN OVER FAR
EASTERN PORTIONS OF THE STATE THIS AFTERNOON AND EARLY TONIGHT AS
WEAK DPVA ASSOC/W THE AFOREMENTIONED SHORTWAVE ENERGY APPROACHES THE
OFFSHORE SFC TROUGH /BAROCLINIC ZONE/. THE RELATIVELY WEAK AND
PROGRESSIVE NATURE OF THE AFOREMENTIONED UPPER LEVEL FEATURES WILL
RESULT IN A BRIEF WINDOW FOR MOISTURE RECOVERY ASSOCIATED WITH WARM
ADVECTION IN EASTERN NC...ESPECIALLY WITH A DRY ARCTIC AIRMASS IN
PLACE IN THE LOWEST 10-15 KFT. WITH THE ABOVE IN MIND...EXPECT ANY
CHANCE FOR PRECIPITATION TO REMAIN ALONG THE IMMEDIATE COAST /OBX/
OR (MORE LIKELY) ENTIRELY OFFSHORE...WHICH IS FORTUNATE GIVEN THAT
THE SURFACE WETBULB PROFILE WOULD SUPPORT FZRA.
TEMPERATURES: A VARIETY OF FACTORS WILL INFLUENCE HIGHS TODAY. WITH
SFC HIGH PRESSURE OVER THE CAROLINAS...EXPECT LITTLE OR NO SURFACE
ADVECTION. THOUGH CLEAR SKIES WILL LIKELY BE PRESENT WEST OF I-95...
BROKEN TO OVERCAST UPPER LEVEL CLOUD COVER (15+ KFT CEILINGS) WILL
BE PRESENT EAST OF I-95 THIS MORNING AS THE CIRRUS SHIELD OVER THE
EASTERN CAROLINAS EXPANDS WESTWARD IN RESPONSE TO THE SHORTWAVE
TRACKING ENE INTO THE MID-ATLANTIC. THE AFOREMENTIONED CIRRUS SHOULD
SHIFT EASTWARD BY MID MORNING (~15Z) AS THE SHORTWAVE TRACKS RAPIDLY
ENE TO THE DELMARVA...THOUGH AN APPROACHING SHEAR AXIS THIS
AFTERNOON COULD RETARD THE EASTWARD RETREAT OF THE CIRRUS SHIELD AND
ALLOW BKN/OVC SKIES TO PERSIST LONGER INTO THE PEAK HEATING CYCLE.
ADDITIONALLY...LOW-LEVEL CLOUD COVER (CEILINGS 2500-3500 FT AGL)
COULD DEVELOP IN ASSOC/W 925-850 MB WARM ADVECTION LATE THIS
AFTERNOON...THOUGH THAT WOULD BE MORE LIKELY AFTER PEAK HEATING. ON
TOP OF ALL OF THE ABOVE...SNOW COVER PERSISTS ACROSS THE REGION AND
WILL CERTAINLY AFFECT HIGHS...ESP EAST OF HIGHWAY 1 IN THE
CENTRAL/NE COASTAL PLAIN WHERE ACCUMULATIONS WERE THE HIGHEST (4-
6"). WITH THE ABOVE IN MIND...HAVE OPTED TO DECREASE HIGHS A FEW
DEGREES...ESP IN THE CENTRAL/NE COASTAL PLAIN WHERE SNOW COVER IS
GREATER AND INTERMITTENT CLOUD COVER MORE LIKELY. LOWS TONIGHT WILL
BE COMPLICATED BY POSSIBLE BROKEN/OVERCAST STRATUS IN THE COASTAL
PLAIN BETWEEN SUNSET-MIDNIGHT...THOUGH CLEARING IS LIKELY AFTER
MIDNIGHT AND TEMPS WOULD RAPIDLY FALL THEREAFTER...ESP WITH A
SNOWPACK PERSISTING IN THE CENTRAL/NE COASTAL PLAIN. EXPECT LOWS IN
THE MID/UPPER TEENS.
ANOTHER WINTER WEATHER ADVISORY FOR BLACK ICE MAY BE NEEDED FOR
PORTIONS OF THE AREA TONIGHT/FRI MORNING...ESPECIALLY IN LOCATIONS
THAT RECEIVED 4-6" OF SNOW (CENTRAL/NE COASTAL PLAIN) AND THAT ARE
UNLIKELY TO EXPERIENCE MELTING OF THE ENTIRE SNOW PACK. -VINCENT
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY/...
AS OF 300 AM THURSDAY...
FRIDAY THROUGH SATURDAY...THE COLD RIDGE WILL SHIFT EAST WITH ONE
LAST COLD MORNING WITH RE-FREEZING SATURDAY OF WHAT DOES NOT MELT IN
SHADY AREAS. THE WARMING DURING THE DAY FOR SATURDAY AND SUNDAY
APPEARS THAT IT MAY BE INHIBITED BY THE EXPECTED WAA/MOIST AIR
ADVECTION PATTERN SURFACE AND ALOFT. THERE MAY EVEN BE SOME SPOTTY
LIGHT RAIN OVER THE WEEKEND. THIS OCCURS BEFORE THE NEXT WAVE OF LOW
PRESSURE IS FORECAST TO APPROACH THE REGION FROM THE LOWER
MISSISSIPPI VALLEY REGION SUNDAY AFTERNOON.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 300 AM THURSDAY...
ALTHOUGH A MUCH NEEDED THAW OUT IS EXPECTED THIS WEEKEND...QUESTION
MARKS REMAIN WITH CHANCES FOR PRECIPITATION LATE THIS WEEKEND
THROUGH MID NEXT WEEK.
THE THEME OF THE MODELS REMAINS A FORECAST MEAN MID/UPPER PATTERN
THAT CONSISTS OF A CLOSED UPPER CIRCULATION OVER HUDSON BAY ALONG
WITH THE DEVELOPMENT OF A WESTERN UNITED STATES TROUGH. AN EASTERN
PACIFIC SYSTEM IS STILL FORECAST TO PLOW INTO THE SOUTHWESTERN
STATES BY MONDAY...THEN TRACK OUT OVER THE PLAINS AND MISSISSIPPI
VALLEY BY TUE-WED. THE ENSEMBLE MEANS ARE PREFERRED OVER THE MAIN
OPERATIONAL MODELS PER WPC.
IT APPEARS THAT A COLD FRONT WILL TRY TO "BACKDOOR" OUR REGION
SUNDAY NIGHT AS THE WAVE OF LOW PRESSURE TRACKS NE OVER EASTERN NC
EARLY MONDAY... THEN OFF THE MID-ATLANTIC COAST MONDAY AFTERNOON.
THE TIMING OF THIS FRONT WILL BE CRITICAL IN THE FORECAST FOR
TEMPERATURES AS IT SHOULD BE DRIVEN BY A COLD SURFACE HIGH PRESSURE
OVER THE MID-WEST (1030+ MB). CURRENT ENSEMBLES SUGGEST THAT THE
MEAN TIMING WOULD PLACE THE BOUNDARY INTO SC BY 12Z MONDAY. IF THIS
OCCURS... P-TYPE WITH THIS SYSTEM MAY BECOME AN ISSUE. THE DEPTH AND
STRENGTH OF THE COLD AIR THIS FAR OUT IS TOO DIFFICULT TO FORECAST.
WE WILL MAINTAIN THE PREVIOUS FORECASTS CONTINUITY AND KEEP ALL
LIQUID FOR SUNDAY NIGHT INTO MONDAY. HOWEVER... HIGHS MAY STAY IN
THE 30S/40S MONDAY NORTH TO SOUTH.
YET ANOTHER STRONGER SYSTEM IS EXPECTED TO BRING RAIN BACK TO THE
REGION LATER TUESDAY AND WEDNESDAY. AGAIN... P-TYPE MAY BECOME MORE
OF A CONCERN IF THE COLD AIR DAMMING DEVELOPS PER SOME MODEL
SOLUTIONS... EVEN THOUGH THE MAIN STORM TRACK IS EXPECTED TO BE SW-
NE ALONG THE MOUNTAINS... WITH MILLER TYPE B SURFACE DEVELOPMENT
OFFSHORE THE MID-ATLANTIC WED. MUCH COLDER AND DRIER AIR AGAIN
EXPECTED WEDNESDAY NIGHT/THURSDAY. -BADGETT
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
AS OF 130 AM THURSDAY...
24 HOUR TAF PERIOD: VFR CONDITIONS WILL PREVAIL TODAY IN ASSOCIATION
WITH MODIFIED ARCTIC HIGH PRESSURE OVER THE CAROLINAS. PATCHY
FREEZING FOG WILL BE POSSIBLE BETWEEN 06-12Z THIS MORNING...
PRIMARILY AT THE KRWI TERMINAL. THE MOST RECENT OB AT KRWI (0559Z)
REPORTED A 1 3/4SM VISIBILITY WITH FOG...AND THAT WILL BE THE BASIS
FOR A TEMPO GROUP MENTIONING SUB-VFR FREEZING FOG AT KRWI THROUGH
SUNRISE. WITH SURFACE HIGH PRESSURE CENTERED OVER THE REGION...
LIGHT/VARIABLE WINDS WILL PREVAIL THROUGH THE TAF PERIOD. A LIGHT
SOUTHERLY RETURN FLOW WILL DEVELOP IN THE LOWER LEVELS BY THE END OF
THE TAF PERIOD AS THE 925-850 MB RIDGE MOVES OFFSHORE. IT IS
POSSIBLE THAT MVFR (PERHAPS IFR) CEILINGS COULD DEVELOP ACROSS
EASTERN NC BY MIDNIGHT FRIDAY MORNING (05Z FRI)...PRIMARILY AT THE
KFAY TERMINAL...THOUGH WITH SOME POTENTIAL AT THE KRWI/KRDU
TERMINALS AS WELL. GIVEN THAT THIS WOULD BE AT THE VERY END OF THE
06Z TAF PERIOD AND THAT CONFIDENCE IS LOW...WILL WAIT FOR THE 12Z
TAF ISSUANCE TO INTRODUCE ANY POTENTIAL FOR SUB-VFR CEILINGS
TONIGHT/FRIDAY MORNING.
LOOKING AHEAD: VFR CONDITIONS WILL PREVAIL ON FRIDAY. IF ANY SUB-VFR
CEILINGS DEVELOP EARLY FRIDAY MORNING (AS MENTIONED ABOVE)...
CEILINGS WOULD BE EXPECTED TO LIFT TO VFR AND SCATTER OUT BY OR
SHORTLY AFTER 15Z. SUB-VFR CONDITIONS ARE EXPECTED TO DEVELOP
SATURDAY AND PERSIST THROUGH THE REMAINDER OF THE WEEKEND IN
ASSOCIATION WITH AN INCREASINGLY MOIST SOUTHERLY RETURN FLOW IN
ADVANCE OF AN APPROACHING COLD FRONT. -VINCENT
&&
.CLIMATE...
RECORD LOWS FOR JANUARY 30TH
GSO 4 DEGREES SET IN 1966
RDU 7 DEGREES SET IN 1977
FAY 8 DEGREES SET IN 1934
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL NOON EST THURSDAY FOR NCZ007>011-
021>028-038>043-073>078-083>086-088-089.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...VINCENT
SHORT TERM...BADGETT
LONG TERM...BADGETT
AVIATION...VINCENT
CLIMATE...ELLIS/TDH
AREA FORECAST DISCUSSION
NWS RALEIGH NC
259 AM EST THU JAN 30 2014
.SYNOPSIS...MODIFIED ARCTIC HIGH PRESSURE WILL REMAIN OVER THE
CAROLINAS THROUGH THURSDAY.
&&
.NEAR TERM /TODAY AND TONIGHT/...
AS OF 255 AM THURSDAY...
...WINTER WEATHER ADVISORY FOR ICE/BLACK ICE WILL CONTINUE THROUGH
NOON...
...ANOTHER WINTER WEATHER ADVISORY FOR BLACK ICE MAY BE NEEDED FOR
PORTIONS OF CENTRAL NC TONIGHT/FRI MORNING...
OVERVIEW: PER THE LATEST WV IMAGERY AND RAP DATA...A SHORTWAVE
TROUGH CENTERED OVER EASTERN TN AT 06Z WILL DEAMPLIFY AS IT LIFTS
ENE TO THE DELMARVA/MID-ATLANTIC COAST BY 18Z...PROGRESSING OFFSHORE
INTO THE ATLANTIC THEREAFTER. ANOTHER SHORTWAVE TROUGH APPROACHING
THE TX/LA GULF COAST AT 06Z WILL DEAMPLIFY AS IT TRACKS ESE/SE INTO
THE GOMEX THIS AFT/EVE...THEN EAST TOWARD THE FL GULF COAST BY 12Z
FRI. WEAK DPVA ASSOCIATED WITH A SHEAR AXIS EXTENDING NORTHWARD FROM
THE AFOREMENTIONED SHORTWAVE WILL TRACK EAST THROUGH THE REGION TO
THE CAROLINA COAST TONIGHT. MODIFIED ARCTIC HIGH PRESSURE WILL
PERSIST ACROSS THE CAROLINAS TODAY. AN ELONGATED SFC TROUGH WILL
PERSIST OFFSHORE THE CAROLINA COAST...IN A REGION OF STRONG
BAROCLINICITY BETWEEN THE AFOREMENTIONED ARCTIC AIRMASS AND THE GULF
STREAM. WEAK CYCLOGENESIS WILL LIKELY OCCUR ALONG PORTIONS OF THE
OFFSHORE TROUGH /BAROCLINIC ZONE/ TODAY AND TONIGHT IN ASSOCIATION
WITH WEAK DPVA ATTENDANT THE AFOREMENTIONED UPPER LEVEL FEATURES.
PRECIPITATION CHANCES: A VERY DRY ARCTIC AIRMASS IS IN PLACE INLAND
ACROSS CENTRAL NC TODAY (00Z GSO RAOB/PWAT 0.05"). UPPER LEVEL
MOISTURE INCREASES TOWARD THE COAST PER THE 00Z MHX RAOB AND 06Z
IR/WV SAT IMAGERY...THOUGH EVEN THERE THE LOWEST 10-15 KFT REMAIN
EXCEEDINGLY DRY. LOW-LEVEL WARM ADVECTION WILL STRENGTHEN OVER FAR
EASTERN PORTIONS OF THE STATE THIS AFTERNOON AND EARLY TONIGHT AS
WEAK DPVA ASSOC/W THE AFOREMENTIONED SHORTWAVE ENERGY APPROACHES THE
OFFSHORE SFC TROUGH /BAROCLINIC ZONE/. THE RELATIVELY WEAK AND
PROGRESSIVE NATURE OF THE AFOREMENTIONED UPPER LEVEL FEATURES WILL
RESULT IN A BRIEF WINDOW FOR MOISTURE RECOVERY ASSOCIATED WITH WARM
ADVECTION IN EASTERN NC...ESPECIALLY WITH A DRY ARCTIC AIRMASS IN
PLACE IN THE LOWEST 10-15 KFT. WITH THE ABOVE IN MIND...EXPECT ANY
CHANCE FOR PRECIPITATION TO REMAIN ALONG THE IMMEDIATE COAST /OBX/
OR (MORE LIKELY) ENTIRELY OFFSHORE...WHICH IS FORTUNATE GIVEN THAT
THE SURFACE WETBULB PROFILE WOULD SUPPORT FZRA.
TEMPERATURES: A VARIETY OF FACTORS WILL INFLUENCE HIGHS TODAY. WITH
SFC HIGH PRESSURE OVER THE CAROLINAS...EXPECT LITTLE OR NO SURFACE
ADVECTION. THOUGH CLEAR SKIES WILL LIKELY BE PRESENT WEST OF I-95...
BROKEN TO OVERCAST UPPER LEVEL CLOUD COVER (15+ KFT CEILINGS) WILL
BE PRESENT EAST OF I-95 THIS MORNING AS THE CIRRUS SHIELD OVER THE
EASTERN CAROLINAS EXPANDS WESTWARD IN RESPONSE TO THE SHORTWAVE
TRACKING ENE INTO THE MID-ATLANTIC. THE AFOREMENTIONED CIRRUS SHOULD
SHIFT EASTWARD BY MID MORNING (~15Z) AS THE SHORTWAVE TRACKS RAPIDLY
ENE TO THE DELMARVA...THOUGH AN APPROACHING SHEAR AXIS THIS
AFTERNOON COULD RETARD THE EASTWARD RETREAT OF THE CIRRUS SHIELD AND
ALLOW BKN/OVC SKIES TO PERSIST LONGER INTO THE PEAK HEATING CYCLE.
ADDITIONALLY...LOW-LEVEL CLOUD COVER (CEILINGS 2500-3500 FT AGL)
COULD DEVELOP IN ASSOC/W 925-850 MB WARM ADVECTION LATE THIS
AFTERNOON...THOUGH THAT WOULD BE MORE LIKELY AFTER PEAK HEATING. ON
TOP OF ALL OF THE ABOVE...SNOW COVER PERSISTS ACROSS THE REGION AND
WILL CERTAINLY AFFECT HIGHS...ESP EAST OF HIGHWAY 1 IN THE
CENTRAL/NE COASTAL PLAIN WHERE ACCUMULATIONS WERE THE HIGHEST (4-
6"). WITH THE ABOVE IN MIND...HAVE OPTED TO DECREASE HIGHS A FEW
DEGREES...ESP IN THE CENTRAL/NE COASTAL PLAIN WHERE SNOW COVER IS
GREATER AND INTERMITTENT CLOUD COVER MORE LIKELY. LOWS TONIGHT WILL
BE COMPLICATED BY POSSIBLE BROKEN/OVERCAST STRATUS IN THE COASTAL
PLAIN BETWEEN SUNSET-MIDNIGHT...THOUGH CLEARING IS LIKELY AFTER
MIDNIGHT AND TEMPS WOULD RAPIDLY FALL THEREAFTER...ESP WITH A
SNOWPACK PERSISTING IN THE CENTRAL/NE COASTAL PLAIN. EXPECT LOWS IN
THE MID/UPPER TEENS.
ANOTHER WINTER WEATHER ADVISORY FOR BLACK ICE MAY BE NEEDED FOR
PORTIONS OF THE AREA TONIGHT/FRI MORNING...ESPECIALLY IN LOCATIONS
THAT RECEIVED 4-6" OF SNOW (CENTRAL/NE COASTAL PLAIN) AND THAT ARE
UNLIKELY TO EXPERIENCE MELTING OF THE ENTIRE SNOW PACK. -VINCENT
&&
.SHORT TERM /THURSDAY AND THURSDAY NIGHT/...
AS OF 225 PM WEDNESDAY...
HIGH PRESSURE WILL REMAIN OVERHEAD ON THURSDAY AND INTO THURSDAY
NIGHT... WILL SOME WARMING ALOFT AND A SLIGHT MODERATION IN TEMPS.
SNOW MELT WITH UNDOUBTEDLY CUT INTO THE WARMING...SO WILL AGAIN KEEP
HIGHS BELOW GUIDANCE...MID 30S AND COOLEST NORTHEAST.
THERE A LITTLE UNCERTAINTY REGARDING SOME ASPECTS OFT HE FORECAST
THURSDAY NIGHT. THE NAM AND GFS SHOW FAIRLY AGGRESSIVE LOW-LEVEL
MOISTURE RETURN OVER THE COASTAL PLAIN...MUCH MORE SO THAN THE
ECMWF. THE NAM EVEN SHOWS LIGHT QPF. IF LIGHT PRECIP DEVELOPED IT
WOULD BE FREEZING RAIN. HOWEVER...THIS IS NOT SUPPORTED BY THE
CONSENSUS OF SREF MEMBERS. THE AMOUNT OF STRATUS SHOWN BY THE NAM
AND GFS EVEN SEEMS A LITTLE TOO AGGRESSIVE GIVEN THAT THE SURFACE
HIGH WILL BE OVERHEAD AND THE LOW-LEVEL FLOW IS SOUTHWESTERLY. MOST
OF THE MOISTURE RETURN IS AT 925MB WHERE THE FLOW IS WEAK AS WELL.
IF WE DO GET SOME MOISTURE RETURN BUT NOT THE DEGREE OF STRATUS IN
THE NAM/GFS...THEN THERE MAY BE FOG ENHANCED BY THE LINGER SNOWPACK
AND GOOD RADIATIONAL COOLING ONCE AGAIN. LOWS WILL BE A BE LESS
COLD AS THE OVERALL AIRMASS CONTINUES TO MODERATE...MID TO UPPER
TEENS MOST AREAS.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
AS OF 230 PM WEDNESDAY...
FRIDAY AND SATURDAY: AS THE SURFACE HIGH MOVES OFFSHORE FRIDAY...A
TROUGH WILL DEVELOP OVER THE MIDWEST AND A SOUTH TO SOUTHWESTERLY
RETURN FLOW WILL SET UP. THE FLOW ALOFT WILL ALSO SHIFT FROM
WESTERLY TO SOUTHWESTERLY AS THE TROUGH DEEPENS. EXPECT A WARMING
TREND THROUGH THIS PERIOD GIVEN THE INCREASED WARM ADVECTION. HIGHS
IN THE MID TO UPPER 40S FRIDAY WILL INCREASE INTO THE MID 50S TO
AROUND 60 DEGREES FOR SATURDAY AND SUNDAY. OVERNIGHT LOWS WILL
MODERATE AS WELL...INCREASING FROM MID TO UPPER 20S FRIDAY NIGHT TO
MID 30S TO LOW 40S SATURDAY NIGHT. MOISTURE ADVECTION THROUGH THE
PERIOD WILL LEAD TO AN INCREASE IN CLOUD COVER FROM THE SOUTHEAST
SATURDAY AND INTO SUNDAY. THIS PERIOD SHOULD BE MOSTLY DRY...WITH
PRECIP CHANCES INCREASING SATURDAY NIGHT AND INTO SUNDAY.
SUNDAY NIGHT THROUGH WEDNESDAY: ALTHOUGH A GOOD DEAL OF UNCERTAINTY
AND DISAGREEMENT BETWEEN THE MODELS EXISTS FROM SUNDAY ONWARD...
EXPECT CHANCES FOR PRECIPITATION THROUGH THE PERIOD. BOTH THE ECMWF
AND GFS INDICATE THE FRONT APPROACHING FROM THE WEST AND ALIGNING
WITH THE MEAN FLOW...WHICH WILL SHIFT FROM SOUTHWESTERLY TO MORE
ZONAL (WEST TO EAST) ON MONDAY AND TUESDAY. AS THIS HAPPENS THE
FRONT WILL LIKELY STALL SOMEWHERE FROM VA TO SC...HOWEVER THE MODELS
DIFFER ON THE LOCATION AND THUS WHERE THE BEST PRECIP CHANCES WILL
BE. FOR NOW WILL INDICATE CHANCES FOR RAIN THROUGH THE PERIOD...
ALTHOUGH AS OF THE 12Z MODEL RUNS THE ECMWF SOLUTION IS WETTER THAN
THE GFS FOR SUNDAY NIGHT INTO MONDAY WHILE THE GFS IS WETTER FOR
TUESDAY. BOTH MODELS INDICATE A TROUGH DIGGING OVER THE MIDWEST
TUESDAY NIGHT...WHICH SHOULD HELP PUSH THE FRONT THROUGH THE AREA...
ALBEIT WITH AN INCREASE IN PRECIPITATION...FROM MID TO LATE WEEK.
THE GFS HINTS AT A POSSIBLE CAD EVENT OVER THE NW FOR TUESDAY BEFORE
THE SURFACE LOW DEVELOPING OVER THE TN/OH VALLEY MOVES NE TOWARD NEW
ENGLAND...TRAILING A COLD FRONT BEHIND IT. TEMPERATURES THROUGH THIS
PART OF THE FORECAST WILL DEPEND ON TIMING AND LOCATION OF THE FRONT
AND THE POTENTIAL CAD. FOR NOW EXPECT HIGHS MONDAY AND TUESDAY IN
THE MID 40S NW TO MID 50S SE...INCREASING WEDNESDAY...LOW 50S NW TO
LOW 60S SE. LOWS WILL BE GENERALLY IN THE MID 30S TO LOW 40S.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
AS OF 130 AM THURSDAY...
24 HOUR TAF PERIOD: VFR CONDITIONS WILL PREVAIL TODAY IN ASSOCIATION
WITH MODIFIED ARCTIC HIGH PRESSURE OVER THE CAROLINAS. PATCHY
FREEZING FOG WILL BE POSSIBLE BETWEEN 06-12Z THIS MORNING...
PRIMARILY AT THE KRWI TERMINAL. THE MOST RECENT OB AT KRWI (0559Z)
REPORTED A 1 3/4SM VISIBILITY WITH FOG...AND THAT WILL BE THE BASIS
FOR A TEMPO GROUP MENTIONING SUB-VFR FREEZING FOG AT KRWI THROUGH
SUNRISE. WITH SURFACE HIGH PRESSURE CENTERED OVER THE REGION...
LIGHT/VARIABLE WINDS WILL PREVAIL THROUGH THE TAF PERIOD. A LIGHT
SOUTHERLY RETURN FLOW WILL DEVELOP IN THE LOWER LEVELS BY THE END OF
THE TAF PERIOD AS THE 925-850 MB RIDGE MOVES OFFSHORE. IT IS
POSSIBLE THAT MVFR (PERHAPS IFR) CEILINGS COULD DEVELOP ACROSS
EASTERN NC BY MIDNIGHT FRIDAY MORNING (05Z FRI)...PRIMARILY AT THE
KFAY TERMINAL...THOUGH WITH SOME POTENTIAL AT THE KRWI/KRDU
TERMINALS AS WELL. GIVEN THAT THIS WOULD BE AT THE VERY END OF THE
06Z TAF PERIOD AND THAT CONFIDENCE IS LOW...WILL WAIT FOR THE 12Z
TAF ISSUANCE TO INTRODUCE ANY POTENTIAL FOR SUB-VFR CEILINGS
TONIGHT/FRIDAY MORNING.
LOOKING AHEAD: VFR CONDITIONS WILL PREVAIL ON FRIDAY. IF ANY SUB-VFR
CEILINGS DEVELOP EARLY FRIDAY MORNING (AS MENTIONED ABOVE)...
CEILINGS WOULD BE EXPECTED TO LIFT TO VFR AND SCATTER OUT BY OR
SHORTLY AFTER 15Z. SUB-VFR CONDITIONS ARE EXPECTED TO DEVELOP
SATURDAY AND PERSIST THROUGH THE REMAINDER OF THE WEEKEND IN
ASSOCIATION WITH AN INCREASINGLY MOIST SOUTHERLY RETURN FLOW IN
ADVANCE OF AN APPROACHING COLD FRONT. -VINCENT
&&
.CLIMATE...
RECORD LOWS FOR JANUARY 30TH
GSO 4 DEGREES SET IN 1966
RDU 7 DEGREES SET IN 1977
FAY 8 DEGREES SET IN 1934
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL NOON EST THURSDAY FOR NCZ007>011-
021>028-038>043-073>078-083>086-088-089.
&&
$$
SYNOPSIS...MWS/VINCENT
NEAR TERM...VINCENT
SHORT TERM...SMITH
LONG TERM...KC
AVIATION...VINCENT
CLIMATE...ELLIS/TDH
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
1011 PM MST WED JAN 29 2014
.UPDATE...
ISSUED AT 815 PM MST WED JAN 29 2014
03Z SFC ANALYSIS PLACES LOW CENTER OVER WCNTRL SD WITH SNOW
FALLING FROM THE BLKHLS INTO FAR NWRN SD. K2WX HAS REPORTED
MEASURED 0.07 AND AREA WEBCAMS SHOW LITTLE FALLING ELSEWHERE ON THE
PLAINS. LOTS OF VIRGA ON RADAR AND ITS TAKING SOME TIME TO
SATURATE THE LOW LEVELS BELOW 600MB (SEE 00Z KUNR SOUNDING). EARLY
00Z MODEL RUNS STILL SHOWING THE BEST ACCUMULATIONS ACRS THE
BLKHLS AS WELL AS FAR NWRN SD THROUGH EARLY THU MRNG...AND THOSE
WINTER WX ADVISORIES LOOK GOOD. STILL SOME QUESTION AS TO HOW MUCH
SNOW WILL FALL ACRS NERN WY...BUT SOME ADVISORY AMOUNTS MAY FALL
NEAR THE MT BORDER. CURRENT FCST IS IN QUITE GOOD SHAPE AND WILL
ONLY MAKE MINOR MODIFICATIONS TO THE GRIDDED FCST AT THIS TIME
BASED ON CURRENT CONDITIONS.
UPDATE ISSUED AT 641 PM MST WED JAN 29 2014
HIGHER RES MODELS FROM THIS AFTERNOON AND THE 00Z RAP HAVE BEEN
SHOWING MORE SNOWFALL (3-6 INCHES) FOR THE HIGHER TERRAIN OF THE
CNTRL/SRN HILLS TONIGHT...PRIMARILY WEST OF MYSTIC...HILL
CITY...AND CUSTER. THIS IS ALSO BEING SUPPORTED BY RECENT HIGHER
RADAR REFLECTIVITIES IN THE SRN HILLS. THUS...HAVE EXPANDED THE
WINTER WX ADVISORIES TO INCLUDE THE CNTRL/SRN BLKHLS. NOTHING ELSE
CHANGED AT THIS TIME.
&&
.SHORT TERM...THIS EVENING THROUGH THURSDAY NIGHT
ISSUED AT 124 PM MST WED JAN 29 2014
20Z SURFACE ANALYSIS HAD COLD FRONT FROM SOUTHERN AB INTO
NORTHEAST MT/NORTHERN ND. WATER VAPOR SHOWED FLAT UPPER RIDGE
OVER THE CWA. UPPER LOW/SHORTWAVE OVER CENTRAL MB MAIN INTEREST
FOR TONIGHT...AND THEN UPPER TROUGH/SERIES OF SHORTWAVES MOVING
FROM THE WEST COAST ACROSS THE ROCKIES INTO THE CENTRAL PLAINS FOR
LATE THURSDAY/THURSDAY NIGHT.
TONIGHT...UPPER LOW/SHORTWAVE SHIFTS INTO CENTRAL ON...SPINNING
SHORTWAVE ENERGY/SHEAR AXIS SOUTH INTO THE CWA. SURFACE LOW PRESSURE
WILL DEVELOP ALONG CURRENT COLD FRONT IN SOUTHERN AB...MOVING
THROUGH CWA TONIGHT...REACHING NORTHWEST IA 12Z THURSDAY. SYNOPTIC
LIFT WILL BE PROVIDED BY DEPARTING 110KT JET STREAK/RIGHT ENTRANCE
REGION...AND APPROACHING 150KT JET STREAK ACROSS THE ROCKIES. VERY
TIGHT LOW LEVEL THERMAL GRADIENT DEVELOPS BEHIND COLD FRONT AND
SUBSEQUENT STRONG FRONTOGENESIS. FEATURES SHOULD SYNC UP OVER
SOUTHEAST MT INTO NORTHWEST SD LEADING TO SEVERAL INCHES OF SNOW BY
THURSDAY MORNING...LIKELY FORMING A HEAVIER BAND OF SNOW SOMEWHERE
FROM FAR NORTHEAST WY INTO NORTHWEST SD. BEHIND COLD FRONT AS HIGH
PRESSURE SETTLES IN...WEAK NORTHEAST UPSLOPE BOUNDARY LAYER FLOW
DEVELOPS ON THE SD PLAINS. FLOW WILL BE MORE NORTHERLY OVER WESTERN
HALF OF CWA WITH FROUDE NUMBERS ABOVE 1 FOR 6-9 HOURS TONIGHT WITH
SATURATED LOW LEVELS. EXPECT UPSLOPE ENHANCED SNOWS OVER THE
NORTHERN BLACK HILLS. WILL HOIST APPROPRIATE HEADLINES WITH
AFTERNOON PACKAGE. TEMPERATURES WILL RETURN TO QUITE CHILLY READINGS
AS COLD AIR OOZES INTO THE AREA OVERNIGHT.
THURSDAY...BETTER SNOWS PUSH EAST OF THE CWA IN THE MORNING AS HIGH
PRESSURE POKES INTO THE DAKOTAS. NEXT UPSTREAM WAVE ALREADY
IMPINGING ON THE ROCKIES WITH LOW FORMING OVER WESTERN WY. LIFT
AHEAD OF SYSTEM WILL LIKELY INCREASE -SN COVERAGE OVER SOUTHWEST
THIRD OF CWA LATE IN THE DAY. TEMPERATURES WILL BE MUCH COLDER THAN
TODAY.
THURSDAY NIGHT...BEST LIFT SHIFTS ACROSS EASTERN WY INTO FAR
SOUTHWEST SD. NOTABLE 850-700MB FRONTOGENESIS...SO HAVE INCREASED
POPS TO ACCOUNT. LATER SHIFTS WILL NEED TO TAKE A CLOSER LOOK AT
WHETHER HEADLINES WILL BE NEEDED.
&&
.LONG TERM...FRIDAY THROUGH WEDNESDAY
ISSUED AT 124 PM MST WED JAN 29 2014
ACTIVE WEST-NORTHWEST FLOW ALOFT WILL CONTINUE TO BRING SOME
UNSETTLED WEATHER OVER SOUTHERN SD FRIDAY...WHICH WILL CLEAR OUT
THROUGH THE DAY. THE ARCTIC BOUNDARY WILL GENERALLY REMAIN TO THE
SOUTH AND WEST OF THE FORECAST AREA THROUGH THE WEEKEND AND INTO
NEXT WEEK...KEEPING TEMPERATURES BELOW AVERAGE. DRY CONDITIONS ARE
EXPECTED THIS WEEKEND INTO THE EARLY WORK WEEK AS HIGH PRESSURE
SLIDES THROUGH THE NORTHERN PLAINS. CHANCES FOR LIGHT SNOW COULD
RETURN OVER WESTERN AND SOUTHERN PORTIONS OF THE CWA TOWARD THE
MIDDLE OF THE WEEK AS ARCTIC AIR MAKES ANOTHER PUSH INTO THE
REGION.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1009 PM MST WED JAN 29 2014
CONDITIONS WILL CONTINUE TO DETERIORATE OVERNIGHT AS SNOW DEVELOPS
ACROSS THE AREA. MVFR/IFR CONDITIONS ARE EXPECTED...ESPECIALLY
FROM NERN WY THROUGH THE BLKHLS INTO NWRN SD...WITH SLIGHTLY
BETTER CONDITIONS EXPECTED ACROSS SWRN/SCNTRL SD. THESE POOR
CONDITIONS ARE EXPECTED TO CONTINUE THROUGH MUCH OF THE DAY
THURSDAY.
&&
.UNR WATCHES/WARNINGS/ADVISORIES...
SD...WINTER WEATHER ADVISORY UNTIL NOON MST THURSDAY FOR SDZ024.
WINTER WEATHER ADVISORY UNTIL 7 AM MST THURSDAY FOR SDZ001-002-
012-013-025-028-029.
WY...WINTER WEATHER ADVISORY UNTIL NOON MST THURSDAY FOR WYZ057.
WINTER WEATHER ADVISORY UNTIL 7 AM MST THURSDAY FOR WYZ054-056-
071.
&&
$$
UPDATE...JOHNSON
SHORT TERM...HELGESON
LONG TERM...13
AVIATION...JOHNSON
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
1125 PM CST WED JAN 29 2014
.AVIATION...
STRATUS CIG AT ABT 3K FT ADVANCING NORTHWARD AND ALREADY MOVING
INTO SRN PORTIONS OF CWA. HAVE INDICATED MVFR CIGS MOVG INTO
KSSF/KSAT TAFS AFT 09Z-10Z AND KAUS BY 11Z...BUT CIGS REMAINING
VFR AT KDRT AS STRATUS SHOULD STAY TO THE EAST OF KDRT. SRLY WNDS
INCREASING TO OVER 15 KTS BY LATE THU MRNG CAUSING MIXING CIGS TO
BECOME VFR AFTER 17Z-18Z. MVFR CIGS WITH PATCHY FOG RETURNING
AFTER 06Z FRIDAY.
&&
.PREV DISCUSSION... /ISSUED 929 PM CST WED JAN 29 2014/
UPDATE...
SATELLITE IMAGERY SHOWS STRATUS WAS JUST SOUTH OF SOUTH CENTRAL
TEXAS AND MOVING NORTH THIS EVENING. EVENING NAM AND RUC RUNS
SHOW LOWER LEVEL MOISTURE AND ASSOCIATED CLOUDS APPROACHING I-35
LATE TONIGHT. THIS SEEMS REASONABLE DUE DEVELOPING SOUTHERLY FLOW.
HAVE BOOSTED CLOUD COVER TO PARTLY TO MOSTLY CLOUDY ALONG AND EAST
OF I-35 LATE TONIGHT INTO EARLY MORNING THURSDAY. DAYTIME MIXING
WILL ERODE THE CLOUDS LATE MORNING INTO AFTERNOON. TEMPERATURES
WILL CONTINUE TO DROP MOST OF THE NIGHT REACHING EXPECTED LOWS AND
THEN RISE TOWARD MORNING AS LOWER LEVEL MOISTURE INCREASES. HAVE
ALSO BOOSTED DEWPOINTS TOWARD MORNING. REMAINDER OF SOUTH CENTRAL
TEXAS FORECAST IS ON TRACK.
PREV DISCUSSION... /ISSUED 536 PM CST WED JAN 29 2014/
AVIATION...
VFR CONDITIONS TO PREVAIL THROUGH FORECAST PERIOD AS HIGH PRESSURE
RIDGE SOUTHEAST OF AREA WEAKENS AND LOW PRESSURE DEEPENS TO THE
NORTHWEST. RESULTANT PRIMARILY SOUTHERLY WINDS OF 5 TO 10 KTS
TONIGHT INCREASING TO 15 TO 20 KNOTS AFTER 15Z THU AND CONTG
THROUGH THU AFTERNOON. SOME SCT CLDS OF 4-5K THU MRNG OVR I-35
TAFS EXPECTED TO ERODE BY THU AFTERNOON.
PREV DISCUSSION... /ISSUED 325 PM CST WED JAN 29 2014/
SHORT TERM (TONIGHT THROUGH THURSDAY NIGHT)...
EXPECT MOSTLY SUNNY SKIES FOR THE REST OF THIS AFTERNOON. MAY SEE
A GROUP OF MID TO UPPER LEVEL CLOUDS MOVING IN FROM THE SOUTHWEST
WITHIN THE NEXT FEW HOURS...HOWEVER...CLEAR SKIES ARE ANTICIPATED THIS
EVENING WITH LIGHT SOUTHERLY WINDS FROM THE GULF. OVERNIGHT LOWS WILL
RANGE FROM THE MID 20S ACROSS THE HILL COUNTRY TO NEAR 30 ACROSS
THE RIO GRANDE PLAINS. THURSDAY`S HIGH TEMPERATURES WILL BE 5 TO
10 DEGREES WARMER THAN TODAY`S HIGH AS SOUTHERLY FLOW REMAINS.
LONG TERM (FRIDAY THROUGH WEDNESDAY)...
A SURFACE HIGH PRESSURE RIDGE OVER THE AREA WILL CONTINUE TO BRING
SOUTHERLY WINDS FOR THE REST OF THE WORK WEEK...RESULTING IN ABOVE
SEASONAL TEMPERATURES ACROSS SOUTH CENTRAL TEXAS WITH HIGHS IN
THE MID 70S ON FRIDAY AND SATURDAY. SOUTHERLY WINDS AND MOISTURE
ARE EXPECTED TO INCREASE ON FRIDAY INTO THE UPCOMING WEEKEND AS AN
UPPER LEVEL LONG-WAVE TROUGH PUSHES ACROSS THE DESERT SOUTHWEST
REGION WHILE SENDING SHORT-WAVE PULSES ACROSS SOUTH CENTRAL TEXAS.
THIS OVERRUNNING PATTERN WILL PRODUCE VERY LIGHT RAIN MAINLY ALONG
AND EAST OF INTERSTATE 35 LATE FRIDAY AND SATURDAY. A COLD FRONT
IS EXPECTED TO PUSH ACROSS THE AREA EARLY SUNDAY AND STALLING
ALONG THE COASTAL PLAINS THROUGH MONDAY. THIS WILL KEEP THE AREA
MOSTLY CLOUDY WITH LOW CHANCES OF RAIN THROUGH THE PERIOD. BY
TUESDAY OF NEXT WEEK...A SHARP UPPER LEVEL SHORT-WAVE TROUGH IS
EXPECTED TO MOVE ACROSS THE SOUTHERN PLAINS WHILE INTERACTING WITH
THE WARM SECTOR OF THE STALL FRONTAL BOUNDARY OVER THE COASTAL
PLAINS. SINCE MEDIUM-RANGE MODELS ARE TRENDING WETTER EACH
RUN...OPTED TO INCREASE POPS UP TO 50 PERCENT ON TUESDAY MAINLY
ACROSS THE NORTHEAST HILL COUNTRY AND EASTERN COUNTIES. QPF
AMOUNTS ARE RANGING FROM ONE TENTH TO ONE HALF INCH. WEATHER
CONDITIONS WILL IMPROVE LATE TUESDAY INTO WEDNESDAY WITH ANOTHER
PLUNGE OF COLD AIR FOR THE MIDDLE OF NEXT WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 30 64 55 76 61 / 0 0 0 - 20
AUSTIN BERGSTROM INTL AIRPORT 23 62 49 75 55 / 0 0 0 - 20
NEW BRAUNFELS MUNI AIRPORT 25 63 47 76 56 / 0 0 0 - 20
BURNET MUNI AIRPORT 27 62 48 74 55 / 0 0 0 - 20
DEL RIO INTL AIRPORT 26 65 42 76 47 / 0 0 0 0 -
GEORGETOWN MUNI AIRPORT 26 63 52 74 57 / 0 0 0 - 20
HONDO MUNI AIRPORT 24 65 44 77 53 / 0 0 0 - 10
SAN MARCOS MUNI AIRPORT 26 62 48 74 56 / 0 0 0 10 20
LA GRANGE - FAYETTE REGIONAL 29 64 55 75 59 / 0 0 10 10 20
SAN ANTONIO INTL AIRPORT 29 65 50 76 59 / 0 0 0 - 20
STINSON MUNI AIRPORT 28 65 48 78 58 / 0 0 0 - 20
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...07
SYNOPTIC/GRIDS...04
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
348 AM CST THU JAN 30 2014
...UPDATED TO ADD TODAY/TONIGHT SECTIONS...
.TODAY...FORECAST CONFIDENCE IS MEDIUM.
IT WILL DEFINITELY BE WINDY AND THERE WILL BE ACCUMULATING SNOW
DURING THE MIDDLE PART OF THE DAY. BASED ON TRACKING OF THE MOVEMENT
OF HIGHER REFLECTIVITY SNOW ON AREA RADARS TO THE WEST...HAVE KEPT
CURRENT TIMING OF SNOW INTO THE WESTERN CWA AROUND 14Z-15Z...
REACHING BERLIN...MADISON AND MONROE AROUND 16Z...PLYMOUTH...
WAUKESHA AND LAKE GENEVA AROUND 17Z...AND MILWAUKEE TO KENOSHA BY
18Z.
SOME CONCERN WITH LATEST HRRR AND RAP THAT KEEP THE SNOW FROM
MADISON AND WEST THROUGH 18Z...SO WILL MONITOR OBS/RADAR AND ADJUST
IF NECESSARY. LEADING AREA OF RETURNS WITH STRONG ISENTROPIC LIFT
OVER SRN MN AND N CENTRAL IOWA...BUT NO GROUND TRUTH WITH 9-10K FT
CEILINGS REFLECTING DRY LAYER BELOW 10K FT ON FORECAST SOUNDINGS
THAT WILL HAVE TO SATURATE BEFORE SNOW REACHES GROUND.
HAVE DROPPED SNOW ACCUMULATIONS A BIT AS NOT QUITE AS MUCH QPF USING
CONSENSUS MODEL AMOUNTS...WHICH WERE HIGHER THAN WPC...WHICH KEEPS
SNOW TOTALS IN THE 1 TO 2 INCH RANGE WITH THE HIGHER AMOUNTS NORTH
WITH BETTER FRONTOGENETIC FORCING...THOUGH AN ISOLATED 3 INCH TOTAL
NOT OUT OF THE QUESTION.
WINDS WILL BE AN ISSUE MAINLY AHEAD OF...AND AT THE ONSET OF THE
SNOW WITH 45-50KT WINDS AT 900-925 MB AHEAD OF LOW. SOME BLOWING AND
DRIFTING EXPECTED WITH THE STRONG WINDS EARLY THIS MORNING...BUT
WITH CURRENT OBS REMAINING AT 10SM WITH GUSTS TO 30 KNOTS...THINK
DRIFTING ON EAST-WEST ROADS IN OPEN AREAS WILL BE THE BIGGER
PROBLEM.
FORECAST SOUNDINGS DO NOT REACH THESE STRONGEST WINDS WITH THE
INVERSION LIMITING MIXING UP TO AROUND 1K FT. THIS WILL KEEP HIGHEST
SUSTAINED WINDS IN THE 20-25 MPH RANGE...AND GUSTS GENERALLY 30-35
MPH WITH A FEW 40 MPH.
NO HEADLINES AS SNOW AMOUNTS AND WINDS DO NOT SUPPORT EITHER AN
ADVISORY FOR SNOW OR WINDS ALONE...THOUGH A CASE COULD BE MADE FOR A
WINTER WEATHER ADVISORY FOR THE SNOW/WIND COMBINATION. GIVEN THAT
THE MAIN PERIOD OF ACCUMULATING SNOW WILL OCCUR DURING THE MIDDAY
HOURS AND NOT DURING EITHER THE MORNING OR EVENING RUSH HOURS...AND
WINDS WILL BE DECREASING AS SNOW MOVES IN...WILL CONTINUE TO
HIGHLIGHT THE TRICKY TRAVEL CONDITIONS WITH FREQUENT SPS ISSUANCES.
.TONIGHT...FORECAST CONFIDENCE IS HIGH.
SNOW EXPECTED TO PUSH EAST OF FORECAST AREA BY 00Z WITH TEMPS
DROPPING BEHIND COLD FRONT. 925 MB TEMPS FALL TO THE TEENS BELOW
ZERO BY 12Z FRIDAY...SUPPORTING LOWS IN THE SINGLE DIGITS ABOVE IN
THE SOUTHEAST HALF OF THE CWA AND ZERO TO THE SINGLE DIGITS BELOW IN
THE NORTHWEST HALF. WIND CHILLS FRIDAY MORNING WILL BE BETWEEN -5
AND -15.
.SHORT TERM...FRIDAY THROUGH SATURDAY NIGHT...FORECAST CONFIDENCE
IS HIGH.
SHORT TERM MODELS SHOW HIGH PRESSURE SLIDING EAST ACROSS THE
REGION ON FRIDAY. ECMWF/CANADIAN MODELS TRY TO NUDGE LIGHT QPF
INTO THE FAR SOUTHERN COUNTIES BY 00Z SATURDAY...WITH THE GFS JUST
SOUTH OF THE BORDER AND NAM FURTHER SOUTH INTO NORTHERN ILLINOIS.
THIS IS IN RESPONSE TO 500 MB VORTICITY MAXIMUM SLIDING INTO THE
AREA DURING THE AFTERNOON.
MID LEVELS ARE MOIST...BUT LOW LEVELS ARE DRY. KEPT LOW POPS IN
THE FAR SOUTH AND SOUTHEAST FRIDAY AFTERNOON PER COORDINATION WITH
NEIGHBORING OFFICES...THOUGH THIS COULD END UP BEING A DRY PERIOD.
COOL HIGHS IN THE TEENS ARE EXPECTED.
SHORT TERM MODELS THEN IN GENERAL AGREEMENT WITH BRINGING SURFACE
LOW NORTHEAST ACROSS MISSOURI FRIDAY NIGHT...THEN TO THE NORTHERN
OHIO AREA SATURDAY. MODELS BRING A 500 MB VORTICITY MAXIMUM
THROUGH THE REGION SATURDAY...ALONG WITH DECENT Q VECTOR
CONVERGENCE AND FRONTOGENESIS RESPONSE IN THE MID LEVELS. CANADIAN
IS TOO AGGRESSIVE FRIDAY NIGHT WITH QPF...AND FAVORED A SOMEWHAT
SLOWER BLEND OF GFS/ECMWF.
MODELS ALL BRING A SWATH OF LIGHT TO MODERATE QPF ACROSS MOST OF
THE AREA SATURDAY MORNING...LINGERING INTO THE AFTERNOON. NAM/GFS
FORECAST SOUNDINGS SHOWING SATURATION IN DEEP LAYER WITH DENDRITE
SNOW GROWTH ZONE BEING TAPPED. BROUGHT IN HIGH POPS INTO THE FAR
SOUTHEAST SATURDAY MORNING...WITH LIKELY IN THE SOUTHEAST HALF OF
THE AREA. KEPT SIMILAR POPS SATURDAY AFTERNOON. AMOUNTS OF 1 TO 2
INCHES NORTHWEST TO 3 TO 4 INCHES SOUTHEAST ARE ANTICIPATED AT
THIS TIME.
MAY SEE MORE SNOW IN THE SOUTHEAST IF MODELS TREND MORE TO THE
NORTH...AND A WINTER WEATHER ADVISORY MAY BE NEEDED FOR LATER
FRIDAY NIGHT INTO SATURDAY IN LATER FORECASTS. WILL CONTINUE TO
MENTION IN HAZARDOUS WEATHER OUTLOOK FOR NOW. COLD AIR ADVECTION
BRINGS DRIER AIR AND QUIET WEATHER INTO THE AREA SATURDAY
NIGHT...AS WELL AS COLDER TEMPERATURES.
.LONG TERM...SUNDAY THROUGH WEDNESDAY...FORECAST CONFIDENCE IS
MEDIUM.
GFS/ECMWF AGREE ON SHOWING HIGH PRESSURE SLIDING EAST SOUTHEAST
ACROSS THE REGION SUNDAY INTO MONDAY. THIS SHOULD BRING QUIET
WEATHER TO THE AREA...ALONG WITH CONTINUED COLD TEMPERATURES.
MODELS THEN BRING A SURFACE LOW FROM THE FAR SOUTHERN PLAINS
ACROSS THE MID MISSISSIPPI RIVER VALLEY MONDAY NIGHT INTO
TUESDAY...THEN NORTHEASTWARD TUESDAY NIGHT INTO WEDNESDAY. GFS
BRINGS A SWATH OF QPF ACROSS THE AREA LATE MONDAY NIGHT INTO
TUESDAY EVENING...WITH THE ECMWF HOLDING OFF UNTIL TUESDAY
AFTERNOON AND NIGHT...ASSOCIATED WITH 500 MB VORTICITY MAXIMUM
AND MID LEVEL FRONTOGENESIS RESPONSE. THESE FEATURES REMAIN TO
THE SOUTH OF THE AREA...SO THERE IS SOME UNCERTAINTY WITH THE
EXACT PLACEMENT OF QPF THIS FAR OUT.
FOR NOW...KEPT CONSENSUS BLEND OF POPS GOING FOR MONDAY NIGHT
INTO WEDNESDAY. POPS MAY NEED TO BE RAISED LATER ON IF BETTER
MODEL AGREEMENT IS REACHED ON THIS SYSTEM. SEVERAL INCHES OF SNOW
IS POSSIBLE. COOL TEMPERATURES LINGER AS WELL.
&&
.AVIATION/12Z TAFS/...COMING SOON...
&&
.MARINE...COMING SOON...
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 9 PM CST THIS EVENING FOR LMZ643>646.
&&
$$
TODAY/TONIGHT AND AVIATION/MARINE...REM
FRIDAY THROUGH WEDNESDAY...WOOD
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1128 PM CST WED JAN 29 2014
.UPDATE...
ISSUED AT 737 PM CST WED JAN 29 2014
29.21Z...22Z AND 23Z RAP CYCLES HAVE BEEN FOLLOWING THE 29.18Z
NAM/GFS CLOSELY...SUGGESTING MORE QPF THAN PREVIOUSLY FORECAST
NORTH OF INTERSTATE 90. AFTER COLLABORATION WITH NEIGHBORING
OFFICES...HAVE RAISED QPF/SNOWFALL AMOUNTS TOWARDS A CONSENSUS OF
THE AFOREMENTIONED MODELS. THE NEW UPDATES GET SNOWFALL TOTALS
CLOSE TO WARNING CRITERIA. HAVE HELD OFF ON A WARNING AT THIS
TIME WITH AMOUNTS IN THE 4 TO 6 INCH RANGE OVER TAYLOR/CLARK
COUNTIES...BUT CLOSE MONITORING OF THIS SYSTEM WILL BE NEEDED.
REGARDING THE METEOROLOGICAL REASONING FOR THE HIGHER QPF AND
SHIFT NORTH...THE 500MB SHORTWAVE SEEN ON WATER VAPOR OVER CENTRAL
MN IS NOW PROGGED TO TAKE A SLIGHTLY FARTHER NORTH TRACK AND BE
STRONGER.
CONSIDERED ALSO SEGMENTING THE ADVISORY TO DELAY THE START TIME
FOR MOST WISCONSIN COUNTIES. HOWEVER...SINCE THE TIME SPLIT WOULD
HAVE ONLY BEEN FOR 2 HOURS...DECIDED TO LEAVE THE ADVISORY TIMES
ALONE. DID SEGMENT THE WSW IN AN ATTEMPT TO ACCOUNT FOR THE SLOWER
ARRIVAL INTO WISCONSIN.
UPDATE ISSUED AT 452 PM CST WED JAN 29 2014
HAVE INCLUDED TAYLOR COUNTY INTO THE WINTER WEATHER ADVISORY.
29.18Z NAM/GFS AND 29.12Z ECMWF ALL HAVE SHOWN A NORTHWARD SHIFT
TO THE SNOWFALL TRACK...WITH THE 29.18Z NAM EVEN SUGGESTING
POTENTIAL OF GETTING CLOSE TO WARNING CRITERIA IN SOME SPOTS. WITH
THE NORTHWARD SHIFT...FELT A NEED TO ACCOUNT FOR THIS BY
INCLUDING TAYLOR COUNTY.
ANOTHER ISSUE NOT ADDRESSED RIGHT NOW IN THE HAZARD OR CURRENT
FORECAST IS THE 29.18Z GUIDANCE SUGGESTING A LITTLE SLOWER TIMING
OF THE PRECIPITATION. FOR EXAMPLE...THE SNOW MAY START IN THE LSE
AREA UNTIL THE END OF THE MORNING COMMUTE...I.E. 8-9 AM. WILL BE
EVALUATING THIS OVER THE NEXT FEW HOURS TO SEE IF SOME OF THE
ADVISORY START TIMES NEED TO BE DELAYED.
INTERESTING TO NOTE...THE SNOW FOR TOMORROW MORNING IS CURRENTLY
IN CENTRAL MONTANA. VISIBILITIES THERE RANGE FROM 1/2 TO 1 SM.
ONE LAST ITEM...THE 29.18Z NAM DOES SHOW A LITTLE MORE WOUND-UP
LOW COMPARED TO ITS 12Z RUN. IF THIS COMES TRUE...THERE COULD BE A
BIT MORE BLOWING AND DRIFTING OF THE SNOW THAT FALLS THURSDAY
MORNING.
&&
.SHORT TERM...(TONIGHT THROUGH THURSDAY NIGHT)
ISSUED AT 259 PM CST WED JAN 29 2014
MAIN FORECAST CONCERN THROUGH THE SHORT TERM IS ACCUMULATING SNOW
LATE TONIGHT INTO THURSDAY AND IMPACT ON MORNING COMMUTE.
WATER VAPOR IMAGERY LOOP/GFS 500MB ANALYSIS SHOW A TROUGH OF LOW
PRESSURE OVER CENTRAL CANADA. WARM AIR ADVECTION AHEAD OF THIS WAVE
HAS PUSHED TEMPERATURES INTO THE TEENS AND LOWER 20S. ATTENTION THEN
TURNS TOWARD A STRONGER WAVE CRASHING INTO THE INTERMOUNTAIN
WEST/NORTHERN ROCKIES VIA 150-170KT JET OFF THE PACIFIC NORTHWEST.
THIS WAVE IS SET TO IMPACT THE AREA LATE TONIGHT INTO THURSDAY WITH
ACCUMULATING SNOW.
WEATHER WILL BEGIN QUIET INITIALLY WITH JUST SOME INCREASE IN
HIGH/MID CLOUD OVERNIGHT AS A COLD FRONT SLIPS SOUTHEAST AND STALLS
OUT ACROSS CENTRAL WI/SOUTHERN MN. SOUTHWEST WINDS AND CLOUD COVER
INCREASE AHEAD OF THE FRONTAL BOUNDARY WILL KEEP TEMPERATURES FAIRLY
STEADY IN THE TEENS. THEN...MODELS IN VERY GOOD AGREEMENT IN
BRINGING A FAIRLY STRONG 700-300MB PV-ANOMALY ACROSS THE BOUNDARY IN
THE 12-18Z TIME FRAME ALONG WITH INCREASING FRONTOGENESIS CENTERED
MAINLY IN THE 850-700MB LAYER. NAM ALSO INDICATES STRONG OMEGA IN THE
-12 TO -18C LAYER FOR DENDRITIC GROWTH POTENTIAL...BUT BUFKIT IS
ONLY SHOWING SNOW-TO-LIQUID RATIOS MAINLY IN THE 12-15:1 RANGE. THIS
IS PROBABLY DUE TO A SMALLER DGZ LESS THAN 100MB AND GOOD AMOUNT OF
WIND SHEAR THROUGH THIS LAYER. NONETHELESS...LOOKS LIKE THE
COMBINATION OF STRONG AGEOSTROPHIC MOTION WITH LEFT EXIT REGION OF
140-150KT JET/FRONTOGENESIS/PV-ANOMALY WILL PRODUCE A FAIRLY BROAD
AREA OF 2-4 INCHES ACROSS THE CWA. THE HEAVIEST SNOW AXIS LOOKS TO
BE CENTERED ALONG THE I-90/94 CORRIDOR REGION IN THE NWS LA CROSSE
FORECAST AREA INTO EAST CENTRAL WI. THE HEAVIEST SNOW RATES AS
ALLUDED TO ABOVE LOOKS LIKE IT WILL OCCUR IN THE 12Z-15Z TIME
FRAME...OR RIGHT IN THE HEART OF THE MORNING COMMUTE WHEN
VISIBILITIES COULD FALL TO 1/2SM AT TIMES. APPEARS THE BULK OF THE
ACCUMULATING SNOW MAY BE OVER WITH BY MID-AFTERNOON...BUT THINKING
THAT THERE MAY BE SOME DRIFTING SNOW ISSUES FOR AWHILE WITH 15-25
MPH WINDS PUSHING IN BEHIND THE DEPARTING WAVE. WITH ALL THIS IN
MIND...HAVE HOISTED A WINTER WEATHER ADVISORY FOR THE ANTICIPATED 2-
4 INCHES OF SNOWFALL VALID FROM 4 AM THROUGH 6 PM THURSDAY.
FRIGID WIND CHILLS THEN BECOME AN ISSUE AGAIN FOR A GOOD PORTION OF
THE AREA THURSDAY NIGHT WITH VALUES DROPPING INTO THE 20-30 BELOW
RANGE. WILL EVENTUALLY HAVE TO HOIST ANOTHER ADVISORY TO COVER THIS.
WILL HOLD OFF UNTIL THE WINTER WEATHER ADVISORY FOR SNOW IS DONE TO
AVOID ANY HEADLINE CONFUSION.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 259 PM CST WED JAN 29 2014
MAIN FORECAST CONCERN FOCUSED ON THE LATE FRIDAY NIGHT THROUGH
SATURDAY TIME FRAME. MODELS SHOWING A WAVE OF LOW PRESSURE
ORIGINATING OUT OF THE COLORADO ROCKIES/SOUTHERN PLAINS MOVING
NORTHEAST ACROSS SOUTHERN/CENTRAL IL. THE ECMWF IS THE FARTHEST
NORTH WITH A SHIELD OF SNOW NORTH OF THE LOW TRACK...PUSHING IT AL
THE WAY INTO THE LA CROSSE FORECAST AREA WHILE OTHER MODELS KEEPING
IT MAINLY SOUTH OF I-90. WENT WITH A MODEL CONSENSUS POP OF 20-40
PERCENT PROBABILITY AT THIS POINT...BUT WILL HAVE TO KEEP A CLOSE
EYE ON THE TRACK AND ADJUST POPS AS NECESSARY. EVEN IF THE ECMWF IS
RIGHT...ONLY LOOKS LIKE AN INCH OR LESS FOR THE AREA. SATURDAY NIGHT
THROUGH MONDAY NIGHT LOOKING QUIET AND CONTINUED COLDER THAN NORMAL
WITH THE MAIN STORM TRACK ACROSS THE SOUTHERN/EASTERN PORTIONS OF
THE CONUS. TEMPERATURE-WISE...LOOK FOR LOWS SATURDAY NIGH THROUGH
MONDAY NIGHT IN THE SINGLE DIGITS ABOVE AND BELOW ZERO WITH HIGHS ON
SUNDAY IN THE SINGLE DIGITS/TENS ABOVE ZERO...WARMING SLIGHTLY
INTO THE TEENS TO AROUND 20 ON MONDAY.
SOUTHERN STREAM BECOMES MORE ACTIVE THIS NEXT WEEK WITH POSSIBLY
ANOTHER STORM SYSTEM BRUSHING FAR SOUTHERN PORTIONS OF THE AREA
TUESDAY/TUESDAY NIGHT WITH LIGHT SNOW.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1128 PM CST WED JAN 29 2014
SNOW ACROSS SOUTHERN NORTH DAKOTA REMAINS ON TRACK TO IMPACT THE
TAF SITES THURSDAY MORNING...BUT THE TIMING IN GENERAL APPEARS TO
AGAIN BE SLIGHTLY LATER. HAVE ADJUSTED THE TAFS TOWARDS A LATER
ARRIVAL...13Z AT RST AND 14Z AT LSE. THERE IS POTENTIAL IT COULD
TAKE ANOTHER HOUR AT LSE. AS THE SNOW MOVES IN...EXPECT THE VFR
CONDITIONS THAT HAVE BEEN IN PLACE TO DROP TO IFR/LIFR AS
VISIBILITIES FALL. CEILINGS FOR THE MOST PART LOOK TO STAY MVFR.
THE SNOW SHOULD MOVE THROUGH IN A FEW HOURS...BUT DUMP UPWARDS OF
1 TO 3 INCHES. BY 19Z...EXPECTING ANY SNOW TO BE REDUCED TO
FLURRIES WITH AN MVFR CEILING HOLDING IN PLACE. BLOWING SNOW MAY
REDUCE VISIBILITIES TO MVFR AT RST DURING THE AFTERNOON. BOTH TAF
SITES SHOULD GO VFR BY 00Z AS DRIER ARCTIC AIR SCOURS OUT THE
CLOUDS.
WINDS REMAIN A PROBLEM. A TIGHT PRESSURE GRADIENT IN PLACE HAS
KEPT RST BREEZY ALL EVENING...ALONG WITH LOW LEVEL WIND SHEAR AT
BOTH SITES. WINDS SHOULD RELAX SOME EARLY THIS MORNING AS THE
GRADIENT WEAKENS...BUT STILL ENOUGH WIND REMAINS ABOVE THE GROUND
TO MAINTAIN LOW LEVEL WIND SHEAR. THAT WIND SHEAR LOOKS TO END
AROUND 12Z. WINDS WILL THEN VEER TO THE NORTHWEST DURING THE LATE
MORNING AND GUST TOWARDS 20-25 KT FOR THE AFTERNOON. EXPECT THE
WINDS TO DIMINISH SOME DURING THE EVENING AS HIGH PRESSURE BUILDS
IN FROM THE WEST.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER WEATHER ADVISORY FROM 4 AM TO 6 PM CST THURSDAY FOR
WIZ017-029-032>034-041>044-053.
MN...WINTER WEATHER ADVISORY FROM 4 AM TO 6 PM CST THURSDAY FOR
MNZ079-086>088-094>096.
IA...WINTER WEATHER ADVISORY FROM 4 AM TO 6 PM CST THURSDAY FOR
IAZ008-009.
&&
$$
UPDATE...AJ
SHORT TERM...DAS
LONG TERM....DAS
AVIATION...AJ
AREA FORECAST DISCUSSION...UPDATED
NWS RENO NV
642 AM PST THU JAN 30 2014
.UPDATE...
WILL BE DROPPING THE WINTER WEATHER ADVISORY FOR CAZ071 (SIERRA
NORTH OF I-80). BASED ON RADAR TRENDS AND MODEL GUIDANCE THREAT
FOR SUBSTANTIAL ADDITIONAL ACCUMULATIONS APPEARS MINIMAL FOR THAT
AREA. A FEW LIGHT SNOW SHOWERS ARE CERTAINLY POSSIBLE THOUGH.
SNOW HAS BEEN PERSISTENT IN THE CARSON VALLEY THIS MORNING
ASSOCIATED WITH LOCALLY LOWER SNOW LEVELS AND BETTER FORCING FOR
ASCENT ALONG COLD FRONT. JUST RECEIVED A SPOTTER REPORT OF 2.5
INCHES IN CARSON CITY. WILL BE UPDATING THE NVZ003 ADVISORY AND
FORECAST TO INCREASE SNOW AMOUNTS IN THAT AREA INTO 1-3 INCH RANGE
FOR THIS MORNING.
NEW GUIDANCE CONTINUES TO ADVERTISE A SECONDARY AREA OF SNOW
TONIGHT ASSOCIATED WITH UPPER SHORTWAVE. LATEST HRRR IS SHOWING
SNOW SHOWERS DEVELOPING QUICKLY AFTER 0Z OVER THE SIERRA AND THEN
PRESSING EASTWARD. THEREFORE HAVE INCREASED POPS AND SNOW
POTENTIAL FOR THE SIERRA AND WESTERN NEVADA INCLUDING RENO/CARSON
CITY FOR TONIGHT. A COUPLE INCHES POSSIBLE DOWN TO THE VALLEY
FLOORS GIVEN LOWER SNOW LEVELS. ANY ACCUMULATIONS WILL RESULT IN
SLICK ROADS GIVEN THE COLDER TEMPERATURES. WE MAY END UP NEEDING
ANOTHER ADVISORY FOR THIS, BUT WILL LET THE DAY SHIFT TAKE A FRESH
LOOK AT THE 12Z GUIDANCE BEFORE DECIDING.
UPDATED FORECAST AND ADVISORIES OUT SHORTLY.
CS
&&
.PREVIOUS DISCUSSION... /ISSUED 327 AM PST THU JAN 30 2014/
SYNOPSIS...
A LOW PRESSURE SYSTEM WILL BRING MOUNTAIN SNOW AND LOWER
ELEVATION RAIN AND SNOW TODAY WITH THE THREAT FOR SNOW SHOWERS
LINGERING THROUGH FRIDAY. HIGH PRESSURE WILL BUILD OVERHEAD FOR
THE WEEKEND WITH DRY CONDITIONS AND BELOW AVERAGE AFTERNOON
TEMPERATURES THROUGH EARLY NEXT WEEK.
SHORT TERM...
GOOD UPPER LEVEL FORCING CONTINUES AHEAD OF THE UPPER LOW APPROACHING
THE CALIFORNIA COAST AS EVIDENCED BY COOLING CLOUD TOPS IN THE
INFRARED SATELLITE. AT THE LOWER LEVELS, A COLD FRONT HAS PUSHED
SOUTH INTO MONO AND MINERAL COUNTIES WITH MOIST FLOW ATOP THE SURFACE
AIRMASS BRINGING A LARGE SWATH OF RAIN AND SNOW TO THE REGION.
MODELS HAVE SHOWN NOTABLE FRONTOGENESIS CENTERED AROUND 12Z/4 AM IN
WESTERN NEVADA FROM ABOUT RENO NORTH FOR A FEW RUNS. BASED ON
PRECIPITATION PLACEMENT (PER RADAR) AND SATELLITE IMAGERY, THE
MODELS MAY HAVE BEEN JUST A BIT TOO FAR NORTH WITH THE BEST FORCING.
BASED ON UPSTREAM ACTIVITY AND THE LATEST 3-KM HRRR, THE HEAVIEST
PRECIPITATION THIS MORNING WILL BE NEAR AND SOUTH OF HIGHWAY 50.
FOR AREAS THAT DO NOT RECEIVE HEAVIER PRECIPITATION IN AREAS BELOW
ABOUT 5500 FEET, LITTLE SNOW IS LIKELY TO ACCUMULATE WITH TEMPERATURES
RUNNING IN THE LOW TO MID 30S (AND NO COLDER OR DRIER AIR TO ADVECT
IN FROM THE NORTH).
STILL, FOR WESTERN NEVADA I WILL LEAVE THE SNOW ADVISORY ABOVE
5000 FEET GOING FOR NOW AS AREAS SOUTH OF RENO IN THE FOOTHILLS
COULD CERTAINLY SEE A FEW INCHES OF SNOWFALL THIS MORNING. AS FAR
AS THE SIERRA, THE FORECAST SEEMS ON TRACK WITH AT LEAST A FEW
MORE HOURS OF MODERATE TO OCCASIONALLY HEAVY SNOWFALL IN THE TAHOE
AREA AND HEAVIER PRECIPITATION WORKING SOUTH TO THE MAMMOTH AREA
THIS MORNING. RESIDUAL SHOWERS WILL CONTINUE INTO THE AFTERNOON
ESPECIALLY SOUTH OF HIGHWAY 50 AND IN THE SIERRA ALTHOUGH WITH
ACTIVITY TAPERING OFF AND DAYTIME ROAD HEATING ACCUMULATIONS
SHOULD REMAIN MODEST.
MOVING ON TO THE SECOND ROUND OF POSSIBLE SNOWFALL FOR TONIGHT,
THE NAM AND GFS CONTINUE TO WIDESPREAD SNOW SHOWERS BREAKING OUT
THIS EVENING AND CONTINUING OVERNIGHT. THE ECMWF ALSO HAS SOME
SHOWER ACTIVITY ALTHOUGH IT IS RESTRICTED TO NEAR THE SIERRA.
SNOW RATIOS WILL BE HIGHER AS THE AIRMASS WILL BE COLDER BY THIS
EVENING SO IT WILL NOT TAKE AS MUCH PRECIPITATION TO CREATE SOME
SNOWFALL. STILL, I AM NOT EXPECTING TOO MUCH SNOWFALL AS THERE IS
NO LOW LEVEL FORCING EVIDENT TO AID UPPER FORCING WITH THE
DISTURBANCE SO SNOW SHOULD REMAIN ON THE LIGHT SIDE.
SNOW SHOWERS TAPER OFF ON FRIDAY AS THE UPPER DISTURBANCE MOVES
OFF INTO CENTRAL AND EASTERN NEVADA. STILL, COLD CYCLONIC FLOW
WILL PERSIST SO A FEW LIGHT SNOW SHOWERS CANNOT BE RULED OUT. IT
WILL BE CHILLY WITH BELOW AVERAGE HIGHS AS 700 MB TEMPERATURES
REMAIN AROUND -10C TO -12C. SNYDER
LONG TERM...SATURDAY THROUGH WEDNESDAY...
GLOBAL MODELS ARE IN REASONABLE AGREEMENT ON THE LARGE SCALE PATTERN
FOR THE EXTENDED, BOTH SHOWING A DEVELOPING RIDGE AROUND 135W WITH
COOL, DRY NW FLOW OVER THE CA/NV REGION. THERE ARE SOME SIGNS OF THE
RIDGE FLATTENING PAST FEB 6, WHICH SHOWS UP IN THE ESRL ANALOGS AS AN
INCREASED CHANCE OF SEEING ANOTHER PACIFIC STORM IN THE D8-14 PERIOD.
PRIMARY ISSUE TO CONTEND WITH IS THE UPPER LOW FORECAST TO DROP SE
ALONG THE CA COASTLINE SUNDAY. GUIDANCE HAS GENERALLY SHOWN PRECIP
ASSOCIATED WITH THIS FEATURE REMAINING WEST OF THE SIERRA, BUT THERE
ARE ABOVE NORMAL SPREADS IN THE GEFS/EC ENSEMBLES SUGGESTING AMPLE
UNCERTAINTY IN THE TRACK/AMPLITUDE OF THE SYSTEM. LATEST EC
SOLUTION IS FURTHER EAST AND BRINGS SHOWERS TO THE CENTRAL/SOUTHERN
SIERRA - SO HAVE INCREASED CHANCES OF SNOW SHOWERS FOR MONO CO
SUNDAY INTO SUNDAY NIGHT. SHOULD THE SYSTEM TRACK FURTHER EAST, THEN
WE COULD BE LOOKING AT ACCUMULATING SNOWS SOUTH OF BRIDGEPORT.
TEMPERATURES SAT/SUN WILL BE QUITE CHILLY GIVEN NE LOW LEVEL FLOW
AND 700MB TEMPS DIPPING TO -12C OR SO. EVEN WITH SUNSHINE, GUIDANCE
HAS TRENDED COOLER FOR SAT/SUN, AND HAVE ADJUSTED THE FORECAST
ACCORDINGLY. WITH CLEAR SKIES ANTICIPATED, SUN MORNING LOWS WILL BE
THE COLDEST WITH WIDESPREAD TEENS IN WRN NV VALLEYS, AND BELOW ZERO
IN THE COLDER SIERRA VALLEYS (WITH SNOWCOVER). REST OF THE EXTENDED
APPEARS LARGELY DRY, ALTHOUGH GUIDANCE SHOWS VARIOUS SMALL SCALE
WAVES EMBEDDED WITHIN THE NW FLOW ALOFT. THESE COULD GENERATE SOME
LIGHT SHOWERS BUT PREDICTABILITY IS LOW - SO I`M MAINTAINING A DRY
FORECAST MON-WED. TEMPERATURES WILL SHOW A SLOW MODERATING TREND. CS
AVIATION...
ONGOING WINTER STORM WILL CONTINUE TO IMPACT THE REGION THROUGH
TODAY. FOLLOWED HRRR GUIDANCE FOR THE MOST PART AS IT`S CAPTURING
CURRENT TRENDS REASONABLY WELL. A SECOND BURST OF SNOW IS POSSIBLE
TONIGHT AND EARLY FRIDAY MORNING WITH A PASSING SHORTWAVE ALOFT
BUT FORECAST CONFIDENCE IN THAT IS LOWER. HERE`S THE DETAILS -
FOR RNO/CXP - PERIODS OF RAIN THROUGH 18Z/TODAY WITH A MIX OF MVFR
AND IFR CONDITIONS. RAIN MAY MIX WITH SNOW AT TIMES AS SNOW LEVELS
FALL TO NEAR 4500-4800 FEET. SNOW ACCUMULATIONS ARE UNLIKELY AT RNO,
BUT NOT ENTIRELY OUT OF THE QUESTION FOR CXP IF WE SEE A
PARTICULARLY HEAVY BURST OF PRECIPITATION BETWEEN 11-15Z. AFTER
18Z, THE BAND OF RAIN/SNOW SINKS SOUTHWARD AND SHOULD PROVIDE A
BREAK THROUGH 03Z/FRIDAY WITH ONLY ISOLATED LIGHT SHOWERS
POSSIBLE. AFTER 03Z/FRIDAY, A SECOND AREA OF SNOW SHOWERS IS
POSSIBLE THROUGH ABOUT 9-12Z/FRIDAY. SNOW LEVELS WOULD BE LOWER,
AND IF THIS SNOW PANS OUT IT WOULD LIKELY ACCUMULATE ON UNTREATED
SURFACES. FORECAST CONFIDENCE IS ADMITTEDLY ONLY LOW TO MEDIUM
RIGHT NOW AS THERE IS STILL VARIABILITY IN MODEL GUIDANCE. BUT
SOMETHING TO WATCH AS IT COULD IMPACT LATE NIGHT OR EARLY MORNING
FLIGHT OPERATIONS.
FOR TVL/TRK - SNOW LEVELS HAVE BEEN SLOW TO FALL AT TVL, REMAINING
RAIN AS OF 9Z. THIS SHOULD CHANGE TO SNOW WITHIN THE NEXT FEW HOURS
AS COLDER AIR MOVES IN. WITHIN GENERAL AREA OF ONGOING RAIN/SNOW,
HRRR GUIDANCE BRINGS IN A BURST OF HEAVY SNOW BETWEEN 11-15Z. THIS
WILL RESULT IN IFR/LIFR CONDITIONS WITH SEVERAL INCHES SNOW
ACCUMULATION. PRECIP INTENSITY SHOULD LIGHTEN UP AFTER 18Z WITH
SCT SNOW SHOWERS REMAINING POSSIBLE THROUGH TODAY. ANOTHER ROUND
OF SNOW IS POSSIBLE BETWEEN ABOUT 00Z-09Z/FRIDAY BUT FORECAST
CONFIDENCE IS LOW TO MEDIUM DUE TO VARIABILITY IN MODEL GUIDANCE.
SHOULD THIS NEXT ROUND OF SNOW PAN OUT, THEN PERIODS OF IFR/LIFR
ARE LIKELY.
FOR MMH - STRONG WESTERLY WINDS ARE ONGOING AS THE AIRFIELD REMAINS
SHADOWED FROM PRECIPITATION. NAM PICKED UP ON THIS WELL AND THESE
WINDS SHOULD START TO SUBSIDE AS RAIN/SNOW MOVES INTO THE AREA AFTER
12Z. PERIODS OF MVFR/IFR CONDITIONS IN SNOW ARE LIKELY BETWEEN 12Z
AND 00Z/FRIDAY WITH MEDIUM TO HIGH FORECAST CONFIDENCE. SNOW
ACCUMULATIONS ARE LIKELY ESPECIALLY AFTER 18Z AS TEMPERATURES DROP.
ANOTHER ROUND OF LIGHT SNOW AND MVFR/IFR CONDITIONS IS POSSIBLE FROM
ROUGHLY 6Z-18Z/FRIDAY BUT FORECAST CONFIDENCE IS LOW DUE TO
VARIABILITY IN MODEL GUIDANCE. CS
&&
.REV WATCHES/WARNINGS/ADVISORIES...
NV...WINTER STORM WARNING UNTIL 4 AM PST FRIDAY NVZ002.
WINTER WEATHER ADVISORY UNTIL 10 AM PST THIS MORNING ABOVE 5000
FEET FOR NVZ003.
CA...WINTER WEATHER ADVISORY UNTIL 4 AM PST FRIDAY ABOVE 7000 FEET
FOR CAZ073.
WINTER STORM WARNING UNTIL 4 AM PST FRIDAY CAZ072.
&&
$$
FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS RENO NV
327 AM PST THU JAN 30 2014
.SYNOPSIS...
A LOW PRESSURE SYSTEM WILL BRING MOUNTAIN SNOW AND LOWER
ELEVATION RAIN AND SNOW TODAY WITH THE THREAT FOR SNOW SHOWERS
LINGERING THROUGH FRIDAY. HIGH PRESSURE WILL BUILD OVERHEAD FOR
THE WEEKEND WITH DRY CONDITIONS AND BELOW AVERAGE AFTERNOON
TEMPERATURES THROUGH EARLY NEXT WEEK.
&&
.SHORT TERM...
GOOD UPPER LEVEL FORCING CONTINUES AHEAD OF THE UPPER LOW APPROACHING
THE CALIFORNIA COAST AS EVIDENCED BY COOLING CLOUD TOPS IN THE
INFRARED SATELLITE. AT THE LOWER LEVELS, A COLD FRONT HAS PUSHED
SOUTH INTO MONO AND MINERAL COUNTIES WITH MOIST FLOW ATOP THE SURFACE
AIRMASS BRINGING A LARGE SWATH OF RAIN AND SNOW TO THE REGION.
MODELS HAVE SHOWN NOTABLE FRONTOGENESIS CENTERED AROUND 12Z/4 AM IN
WESTERN NEVADA FROM ABOUT RENO NORTH FOR A FEW RUNS. BASED ON
PRECIPITATION PLACEMENT (PER RADAR) AND SATELLITE IMAGERY, THE
MODELS MAY HAVE BEEN JUST A BIT TOO FAR NORTH WITH THE BEST FORCING.
BASED ON UPSTREAM ACTIVITY AND THE LATEST 3-KM HRRR, THE HEAVIEST
PRECIPITATION THIS MORNING WILL BE NEAR AND SOUTH OF HIGHWAY 50.
FOR AREAS THAT DO NOT RECEIVE HEAVIER PRECIPITATION IN AREAS BELOW
ABOUT 5500 FEET, LITTLE SNOW IS LIKELY TO ACCUMULATE WITH TEMPERATURES
RUNNING IN THE LOW TO MID 30S (AND NO COLDER OR DRIER AIR TO ADVECT
IN FROM THE NORTH).
STILL, FOR WESTERN NEVADA I WILL LEAVE THE SNOW ADVISORY ABOVE
5000 FEET GOING FOR NOW AS AREAS SOUTH OF RENO IN THE FOOTHILLS
COULD CERTAINLY SEE A FEW INCHES OF SNOWFALL THIS MORNING. AS FAR
AS THE SIERRA, THE FORECAST SEEMS ON TRACK WITH AT LEAST A FEW
MORE HOURS OF MODERATE TO OCCASIONALLY HEAVY SNOWFALL IN THE TAHOE
AREA AND HEAVIER PRECIPITATION WORKING SOUTH TO THE MAMMOTH AREA
THIS MORNING. RESIDUAL SHOWERS WILL CONTINUE INTO THE AFTERNOON
ESPECIALLY SOUTH OF HIGHWAY 50 AND IN THE SIERRA ALTHOUGH WITH
ACTIVITY TAPERING OFF AND DAYTIME ROAD HEATING ACCUMULATIONS
SHOULD REMAIN MODEST.
MOVING ON TO THE SECOND ROUND OF POSSIBLE SNOWFALL FOR TONIGHT,
THE NAM AND GFS CONTINUE TO WIDESPREAD SNOW SHOWERS BREAKING OUT
THIS EVENING AND CONTINUING OVERNIGHT. THE ECMWF ALSO HAS SOME
SHOWER ACTIVITY ALTHOUGH IT IS RESTRICTED TO NEAR THE SIERRA.
SNOW RATIOS WILL BE HIGHER AS THE AIRMASS WILL BE COLDER BY THIS
EVENING SO IT WILL NOT TAKE AS MUCH PRECIPITATION TO CREATE SOME
SNOWFALL. STILL, I AM NOT EXPECTING TOO MUCH SNOWFALL AS THERE IS
NO LOW LEVEL FORCING EVIDENT TO AID UPPER FORCING WITH THE
DISTURBANCE SO SNOW SHOULD REMAIN ON THE LIGHT SIDE.
SNOW SHOWERS TAPER OFF ON FRIDAY AS THE UPPER DISTURBANCE MOVES
OFF INTO CENTRAL AND EASTERN NEVADA. STILL, COLD CYCLONIC FLOW
WILL PERSIST SO A FEW LIGHT SNOW SHOWERS CANNOT BE RULED OUT. IT
WILL BE CHILLY WITH BELOW AVERAGE HIGHS AS 700 MB TEMPERATURES
REMAIN AROUND -10C TO -12C. SNYDER
.LONG TERM...SATURDAY THROUGH WEDNESDAY...
GLOBAL MODELS ARE IN REASONABLE AGREEMENT ON THE LARGE SCALE PATTERN
FOR THE EXTENDED, BOTH SHOWING A DEVELOPING RIDGE AROUND 135W WITH
COOL, DRY NW FLOW OVER THE CA/NV REGION. THERE ARE SOME SIGNS OF THE
RIDGE FLATTENING PAST FEB 6, WHICH SHOWS UP IN THE ESRL ANALOGS AS AN
INCREASED CHANCE OF SEEING ANOTHER PACIFIC STORM IN THE D8-14 PERIOD.
PRIMARY ISSUE TO CONTEND WITH IS THE UPPER LOW FORECAST TO DROP SE
ALONG THE CA COASTLINE SUNDAY. GUIDANCE HAS GENERALLY SHOWN PRECIP
ASSOCIATED WITH THIS FEATURE REMAINING WEST OF THE SIERRA, BUT THERE
ARE ABOVE NORMAL SPREADS IN THE GEFS/EC ENSEMBLES SUGGESTING AMPLE
UNCERTAINTY IN THE TRACK/AMPLITUDE OF THE SYSTEM. LATEST EC
SOLUTION IS FURTHER EAST AND BRINGS SHOWERS TO THE CENTRAL/SOUTHERN
SIERRA - SO HAVE INCREASED CHANCES OF SNOW SHOWERS FOR MONO CO
SUNDAY INTO SUNDAY NIGHT. SHOULD THE SYSTEM TRACK FURTHER EAST, THEN
WE COULD BE LOOKING AT ACCUMULATING SNOWS SOUTH OF BRIDGEPORT.
TEMPERATURES SAT/SUN WILL BE QUITE CHILLY GIVEN NE LOW LEVEL FLOW
AND 700MB TEMPS DIPPING TO -12C OR SO. EVEN WITH SUNSHINE, GUIDANCE
HAS TRENDED COOLER FOR SAT/SUN, AND HAVE ADJUSTED THE FORECAST
ACCORDINGLY. WITH CLEAR SKIES ANTICIPATED, SUN MORNING LOWS WILL BE
THE COLDEST WITH WIDESPREAD TEENS IN WRN NV VALLEYS, AND BELOW ZERO
IN THE COLDER SIERRA VALLEYS (WITH SNOWCOVER). REST OF THE EXTENDED
APPEARS LARGELY DRY, ALTHOUGH GUIDANCE SHOWS VARIOUS SMALL SCALE
WAVES EMBEDDED WITHIN THE NW FLOW ALOFT. THESE COULD GENERATE SOME
LIGHT SHOWERS BUT PREDICTABILITY IS LOW - SO I`M MAINTAINING A DRY
FORECAST MON-WED. TEMPERATURES WILL SHOW A SLOW MODERATING TREND. CS
&&
.AVIATION...
ONGOING WINTER STORM WILL CONTINUE TO IMPACT THE REGION THROUGH
TODAY. FOLLOWED HRRR GUIDANCE FOR THE MOST PART AS IT`S CAPTURING
CURRENT TRENDS REASONABLY WELL. A SECOND BURST OF SNOW IS POSSIBLE
TONIGHT AND EARLY FRIDAY MORNING WITH A PASSING SHORTWAVE ALOFT
BUT FORECAST CONFIDENCE IN THAT IS LOWER. HERE`S THE DETAILS -
FOR RNO/CXP - PERIODS OF RAIN THROUGH 18Z/TODAY WITH A MIX OF MVFR
AND IFR CONDITIONS. RAIN MAY MIX WITH SNOW AT TIMES AS SNOW LEVELS
FALL TO NEAR 4500-4800 FEET. SNOW ACCUMULATIONS ARE UNLIKELY AT RNO,
BUT NOT ENTIRELY OUT OF THE QUESTION FOR CXP IF WE SEE A
PARTICULARLY HEAVY BURST OF PRECIPITATION BETWEEN 11-15Z. AFTER
18Z, THE BAND OF RAIN/SNOW SINKS SOUTHWARD AND SHOULD PROVIDE A
BREAK THROUGH 03Z/FRIDAY WITH ONLY ISOLATED LIGHT SHOWERS
POSSIBLE. AFTER 03Z/FRIDAY, A SECOND AREA OF SNOW SHOWERS IS
POSSIBLE THROUGH ABOUT 9-12Z/FRIDAY. SNOW LEVELS WOULD BE LOWER,
AND IF THIS SNOW PANS OUT IT WOULD LIKELY ACCUMULATE ON UNTREATED
SURFACES. FORECAST CONFIDENCE IS ADMITTEDLY ONLY LOW TO MEDIUM
RIGHT NOW AS THERE IS STILL VARIABILITY IN MODEL GUIDANCE. BUT
SOMETHING TO WATCH AS IT COULD IMPACT LATE NIGHT OR EARLY MORNING
FLIGHT OPERATIONS.
FOR TVL/TRK - SNOW LEVELS HAVE BEEN SLOW TO FALL AT TVL, REMAINING
RAIN AS OF 9Z. THIS SHOULD CHANGE TO SNOW WITHIN THE NEXT FEW HOURS
AS COLDER AIR MOVES IN. WITHIN GENERAL AREA OF ONGOING RAIN/SNOW,
HRRR GUIDANCE BRINGS IN A BURST OF HEAVY SNOW BETWEEN 11-15Z. THIS
WILL RESULT IN IFR/LIFR CONDITIONS WITH SEVERAL INCHES SNOW
ACCUMULATION. PRECIP INTENSITY SHOULD LIGHTEN UP AFTER 18Z WITH
SCT SNOW SHOWERS REMAINING POSSIBLE THROUGH TODAY. ANOTHER ROUND
OF SNOW IS POSSIBLE BETWEEN ABOUT 00Z-09Z/FRIDAY BUT FORECAST
CONFIDENCE IS LOW TO MEDIUM DUE TO VARIABILITY IN MODEL GUIDANCE.
SHOULD THIS NEXT ROUND OF SNOW PAN OUT, THEN PERIODS OF IFR/LIFR
ARE LIKELY.
FOR MMH - STRONG WESTERLY WINDS ARE ONGOING AS THE AIRFIELD REMAINS
SHADOWED FROM PRECIPITATION. NAM PICKED UP ON THIS WELL AND THESE
WINDS SHOULD START TO SUBSIDE AS RAIN/SNOW MOVES INTO THE AREA AFTER
12Z. PERIODS OF MVFR/IFR CONDITIONS IN SNOW ARE LIKELY BETWEEN 12Z
AND 00Z/FRIDAY WITH MEDIUM TO HIGH FORECAST CONFIDENCE. SNOW
ACCUMULATIONS ARE LIKELY ESPECIALLY AFTER 18Z AS TEMPERATURES DROP.
ANOTHER ROUND OF LIGHT SNOW AND MVFR/IFR CONDITIONS IS POSSIBLE FROM
ROUGHLY 6Z-18Z/FRIDAY BUT FORECAST CONFIDENCE IS LOW DUE TO
VARIABILITY IN MODEL GUIDANCE. CS
&&
.REV WATCHES/WARNINGS/ADVISORIES...
NV...WINTER STORM WARNING UNTIL 4 AM PST FRIDAY NVZ002.
WINTER WEATHER ADVISORY UNTIL 10 AM PST THIS MORNING ABOVE 5000
FEET FOR NVZ003.
CA...WINTER WEATHER ADVISORY UNTIL 10 PM PST THIS EVENING ABOVE 5000
FEET FOR CAZ071.
WINTER WEATHER ADVISORY UNTIL 4 AM PST FRIDAY ABOVE 7000 FEET
FOR CAZ073.
WINTER STORM WARNING UNTIL 4 AM PST FRIDAY CAZ072.
&&
$$
FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1055 AM EST THU JAN 30 2014
.UPDATE...
ISSUED AT 1052 AM EST THU JAN 30 2014
...MUCH OF CNTRL CWA UPGRADED WINTER STORM WARNING THROUGH REST OF
THE DAY...
VERY HEALTHY DYNAMIC UPPER LEVEL SYSTEM IMPACTS UPR MICHIGAN THROUGH
THE AFTN...BRINGING MODERATE TO HEAVY SNOW TO MUCH OF THE CWA. WV
LOOP SHOWS INITIAL SHORTWAVE PUSHING ACROSS NORTHERN IOWA WITH COMMA
HEAD BACK OVER SOUTHERN MINNESOTA. DIFFLUENCE ALOFT IS STRONG AS
UPPER LAKES IS WITHIN COUPLED JET STRUCTURE WITH JET STREAK OVER
ONTARIO AND ANOTHER SLIDING TOWARD NORTHERN ILLINOIS. AGEOSTROPIC
RESPONSE ONLY INCREASES THROUGH THE DAY ACROSS UPR MICHIGAN HELPING
TO INCREASE THE ALREADY PRESENT DIVERGENCE ALOFT. SNOW THAT ARRIVED
QUICKER THAN EXPECTED THIS MORNING WAS MOSTLY DUE TO ISENTROPIC
ASCENT AT 285K AHEAD OF COLD FRONT NOW MOVING TO IWD-MQT CORRIDOR.
THIS ISENTROPIC LIFT HAS ALREADY PRODUCED 1-2 INCHES FROM DICKINSON
THROUGH ALGER COUNTIES PER THE 88D SNOW ALGORITHM USING A SLR OF
18:1. WV LOOP AND RADAR UPSTREAM/SFC OBS INDICATE WE STILL HAVE TO GO
THROUGH A SWATH OF HEAVY SNOW OVER CNTRL UPR MICHIGAN THIS AFTN.
RUC13/NAM12 BOTH SHOW THIS FAVORED AREA WILL BE ALONG AND NORTH OF
INITIAL SHORTWAVE MOVING ACROSS NORTHERN LK MICHIGAN AND ALSO JUST
TO THE NORTH AND EAST OF SFC LOW LIFTING INTO NORTHEAST WI. SNOW WILL
ALSO BE HELPED ALONG BY H85-H65 FRONTOGENESIS AND PERHAPS SOME
NEGATIVE EPV ATOP THAT FGEN WHICH COULD RESULT IN BANDED SNOW...FURTHER
BOOSTING SNOW TOTALS. OVERALL...EXPECT 3-5 INCHES OVER ROUGHLY THE
EAST 2/3 OF THE CWA. HOWEVER...IN THESE CNTRL CWA AREAS
HIGHLIGHTED...COULD SEE TOTALS OVER 6 INCHES FROM IRON MOUNTAIN TO
ESCANABA...NORTH TO GWINN AND MUNISING.
UPGRADED AREAS IN THE CNTRL CWA TO A WINTER STORM WARNING FOR EXPECTED
5-8" OF SNOW FALLING DURING THE DAYTIME HOURS AND THIS WILL CERTAINLY
IMPACT THE EVENING COMMUTE. OTHER THAN THE FAR EAST... WHERE GUSTY
SOUTH WINDS ARE STILL RESULTING IN BLSN AND WILL DO SO INTO THE
AFTN...WINDS ARE MAINLY LIGHT WITH THIS SYSTEM. FOR THE OTHER AREAS
AWAY FM THE CNTRL CWA KEPT THE ADVY GOING. ENDING TIME OF THESE
HEADLINES STILL LOOKS GOOD AT 00Z THIS EVENING. &&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 545 AM EST THU JAN 30 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A CLOSED MID LEVEL LOW
OVER NRN ONTARIO. IN THE BAND OF DEEP LAYER FORCING ASSOCIATED WITH
FEATURE...RADAR IMAGERY HAS SHOWN GOOD RADAR RETURNS FOR THE LAST
FEW HRS OVER LAKE SUPERIOR EXTENDING INTO PORTIONS OF THE ERN FCST
AREA. LOW-LEVEL DRY AIR HAS PROBABLY PREVENTED MUCH SNOW FROM
REACHING THE GROUND...AND MDOT WEBCAM/WEATHER STATION AT SENEY
INDICATES NOT MUCH GOING ON THERE DESPITE RADAR RETURNS. FARTHER N
TOWARD GRAND MARAIS...HAVE TO BELIEVE THERE IS SNOW FALLING IN THAT
AREA BASED ON INTENSITY OF RADAR RETURNS. COLD FRONT ASSOCIATED WITH
ONTARIO SYSTEM IS PASSING ACROSS WRN LAKE SUPERIOR. TO THE W...
ATTENTION IS ON SHORTWAVE MOVING ACROSS THE NRN PLAINS. AT THE
SFC...A LOW PRES WAVE HAS DEVELOPED ALONG THE SE SD/NE NEBRASKA
BORDER. AS SHORTWAVE MOVES E...SFC WAVE WILL TRACK ALONG COLD FRONT
MOVING ACROSS UPPER MI TODAY...PRODUCING A WIDESPREAD SNOW FOR MUCH
OF UPPER MI.
MODEL GUIDANCE HAS DEFINITELY TRENDED N AND W WITH SNOW BAND THAT
WILL ACCOMPANY SHORTWAVE...AND PCPN AMOUNTS HAVE TRENED UP AS WELL.
OVERALL...A GOOD SNOW EVENT APPEARS TO BE SHAPING UP TODAY. RATHER
STRONG DEEP LAYER FORCING PER QVECTORS IS INDICATED TO SHIFT ACROSS
THE AREA IN CONCERT WITH A BAND OF LOW-MID FRONTOGENESIS. AT THE
UPPER LEVELS...THERE ARE INDICATIONS OF SOME UPPER JET COUPLING BTWN
THE RIGHT ENTRANCE OF JET ASSOCIATED WITH NRN ONTARIO MID LEVEL LOW
AND LEFT EXIT OF JET ASSOCIATED WITH APPROACHING SHORTWAVE. THIS
COMES TOGETHER RIGHT OVER UPPER MI. MIXING RATIOS OF 2G/KG ARE NOTED
AROUND 700MB...SUGGESTING POTENTIAL FOR AROUND 4 INCHES OF SNOW.
HOWEVER...GIVEN SOME OF THE FORCING MECHANISMS NOTED ABOVE...
DEFINITELY HAVE CONCERN THAT AMOUNTS COULD REACH 6 INCHES OR
MORE...ESPECIALLY IF FOCUSED FRONTOGENETICAL FORCING DEVELOPS. SOME
HIGH RES MODEL GUIDANCE SUGGESTS THIS POTENTIAL COULD OCCUR ROUGHLY
ALONG AN AXIS FROM IRON RIVER TO MARQUETTE. HOURLY RUC13 MODEL RUNS
HAVE BEEN BEEFING UP PCPN AMOUNTS. 09Z RUN HAS AROUND 0.5 INCHES
ALONG THE AXIS MENTIONED. WILL BE SOMETHING TO MONITOR AS THE SNOW
AREA BECOMES ORGANIZED AND MORE INTENSE WHILE MOVING INTO UPPER MI.
HAVE EXPANDED WINTER WX ADVY TO COVER ALL BUT NRN HOUGHTON/KEWEENAW
COUNTIES TODAY. FORTUNATELY...THE STRONG WINDS NOW OCCURRING
DOWNWIND OF LAKE MI WILL BE SUBSIDING AS THE HEAVIER SNOW ARRIVES.
IN THE END...BLSN MAY NOT BE MUCH OF A PLAYER ANYWHERE DURING THE
MAIN PERIOD OF SNOWFALL. FOR SNOWFALL...EXPECT A GENERAL 3 TO 5 INCH
SNOWFALL ACROSS THE ADVY AREA WITH THE HEAVIEST SNOW PROBABLY IN A
WSW TO ENE BAND FROM ERN GOGEBIC/IRON/DICKINSON COUNTIES TO
BARAGA/MARQUETTE/ALGER COUNTIES.
SNOW WILL QUICKLY WIND DOWN/END FROM W TO E MID AFTN TO EARLY
EVENING. WNW TO W FLOW LES WILL FOLLOW TONIGHT AS 850MB TEMPS FALL
TO -16 TO -20C. HOWEVER...SHARP DROP OF INVERSION TO 3-4KFT COMBINED
WITH DRIER AIR SHOULD GREATLY LIMIT INTENSITY OF LES. ICE COVER ON
LAKE SUPERIOR WILL BE NEGATIVE FACTOR AS WELL. TEMPS ARE TRICKY. IF
WIND DECOUPLE AND CLOUD COVER CLEARS OUT SUFFICIENTLY...TEMPS WILL
PLUMMET AWAY FROM LAKE EFFECT AREAS. TRADITIONAL COLD SPOTS COULD
EASILY FALL WELL DOWN INTO THE -20S. FCST REFLECTS A CONSERVATIVE
APPROACH WITH TEMPS MAINLY IN THE SINGLE DIGITS TO LOW TEENS BELOW
ZERO. TEMPS SHOULD STAY ABOVE ZERO OVER THE FAR NE FCST AREA. WIND
CHILL MAY BE NEAR ADVY CRITERIA OVER PORTIONS OF THE W LATE
TONIGHT.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 519 AM EST THU JAN 30 2014
WILL START OUT WITH MAINLY ZONAL FLOW ALOFT FRIDAY MORNING. THAT
WILL QUICKLY CHANGE TO SW FLOW FRIDAY EVENING IN RESPONSE TO THE
MAIN 500MB LOW SHIFTING INTO N HUDSON BAY/QUEBEC...AND THE NEXT WAVE
SINKING IN FROM ONTARIO. QUICKENED THE END TO THE LIKELY POPS OVER
THE KEWEENAW PENINSULA...AND NEAR/EAST OF GRAND MARAIS FRIDAY AS SFC
WINDS BECOME MORE SW-W CUTTING OFF THE FLOW OF LINGERING MOISTURE
OFF LAKE SUPERIOR. HIGH TEMPS WILL STRUGGLE TO RISE INTO THE DOUBLE
DIGITS ABOVE ZERO FRIDAY...AND DEPENDING ON THE EXTENT OF ICE
COVERAGE OVER W LAKE SUPERIOR...MAY REMAIN IN THE LOW SINGLE DIGITS
ABOVE ZERO ACROSS THE W THIRD OF THE CWA.
GIVEN LOWS BOTTOMING OUT IN THE -10 TO 0 RANGE FRIDAY NIGHT/SATURDAY
MORNING...COULD HAVE A FEW POCKETS OF NEAR 20F WIND CHILL READINGS
OVER THE W HALF OF THE CWA...EVEN WITH LIGHT WINDS AVERAGING 5KTS OR
LESS. ALTHOUGH THERE WILL BE A COUPLE OF PERIODS OF WIND CHILL
VALUES IN THE 15-20 DEGREE RANGE...WILL LEAVE IT OUT OF THE HWO FOR
NOW...PARTICULARLY IN THE EXTENDED PERIOD WHERE OUR WIND FCST TENDS
TO BE TOO HIGH TO BEGIN WITH.
THE SW TO NE ORIENTED 500MB TROUGH SET UP FROM UT/CO TO FAR SE
MANITOBA SATURDAY AFTERNOON WILL SWEEP ACROSS THE UPPER GREAT LAKES
SATURDAY NIGHT INTO EARLY SUNDAY. CUT BACK ON THE S STREAM SLIGHT
CHANCE TO CHANCE POPS FOR SATURDAY AFTERNOON AND EVENING OVER THE S
AND E CWA. FCST MODELS LOOK TO BE CONSOLIDATING ON A SFC LOW TRACK
FROM N TX SATURDAY MORNING TO S/CENTRAL IL AT 18Z..AND N IN TO THE
LOWER GREAT LAKES AT 00Z SUNDAY. WHILE SOME SNOW WILL BE POSSIBLE ON
THE BACK SIDE OF THIS LOW SATURDAY AFTERNOON AND EARLY EVENING...IT
LOOKS LIKE THE BEST CHANCE WILL REMAIN TO OUR SE.
COLDER AIR SLIDING IN HOWEVER WILL BRING BACK A CHANCE OF LES TO THE
W FROM SATURDAY AFTERNOON...ON NW TO WNW WINDS AS 850MB TEMPS SLIDE
BACK INTO THE -15 TO -20C RANGE. WILL NOT GO TOO HIGH ON POPS FOR
SATURDAY AFTERNOON ON LES WISE...AS NOTED ABOVE...IT WILL GREATLY
DEPEND ON THE EXTENT OF ICE COVER ACROSS LAKE SUPERIOR. NO
SIGNIFICANT SNOW OR EXTREME /WIND CHILL WARNING/ COLD EVENTS ARE
FIGURED THROUGH THE REST OF THE PERIOD. THE NEXT POTENTIAL FOR
SYSTEM SNOW WILL ONCE AGAIN CLIP US TO THE S TUESDAY NIGHT AS THE
SFC LOW TRACKS UP THE OH VALLEY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 706 AM EST THU JAN 30 2014
A DISTURBANCE MOVING ALONG A COLD FRONT PUSHING ACROSS UPPER MI WILL
BRING SNOW TO THE AREA TODAY. EXPECT IFR CONDITIONS TO DEVELOP AT
KIWD/KCMX/KSAW MID TO LATE MORNING. HEAVIER SNOW IS EXPECTED TO
IMPACT KSAW...RESULTING IN SEVERAL HRS OF LIFR CONDITIONS. AFTER
THE DISTURBANCE DEPARTS...MVFR WX WILL RETURN. BEST CHC FOR MORE
PERSISTENT SHSN/IFR VIS WILL BE AT THE MORE EXPOSED KCMX LOCATION
WITH WNW FLOW BEHIND FROPA PRESENTING AN UPSLOPE WIND COMPONENT...
BUT ICE COVERAGE OVER WRN LAKE SUPERIOR MIGHT LIMIT THE
COVERAGE/INTENSITY OF THESE SHSN. DOWNSLOPE NATURE OF THIS FLOW WILL
RESULT IN VFR CONDITIONS DEVELOPING AT KSAW THIS EVENING. VFR
CONDITIONS WILL RETURN TO KIWD OVERNIGHT IF NOT SOONER AS WINDS BACK
SOME.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 256 AM EST THU JAN 30 2014
GALE FORCE GUSTS TO 35 KNOTS WILL REMAIN POSSILE EARLY THIS MORNING
E. WHILE HEAVY FREEZING SPRAY WILL BE LIMITED ELSEHWERE DUE
SIGNIFICANT ICE COVERING THE WATER...HEAVY FREEZING SPRAY WILL
REMAIN A CONCERN OVER E PORTIONS OF LAKE SUPERIOR THROUGH FRIDAY. A
FEW GALE FORCE GUSTS WILL ALSO BE POSSIBLE TONIGHT.
A LOW OVER CENTRAL ONTARIO WILL SHIFT E OF JAMES BAY THIS
EVENING...PULLING A TROUGH ACROSS LAKE SUPERIOR TODAY. HIGH PRESSURE
WILL THEN MOVE SE FROM ALBERTA TO S WI BY FRIDAY...WHILE BRINGING A
WEAK RIDGE OVER LAKE SUPERIOR. THEN ON SATURDAY...A TROUGH WILL MOVE
E ACROSS THE UPPER GREAT LAKES. THIS WILL BE FOLLOWED BY A HIGH OVER
THE MID MS VALLEY...WHICH WILL PASS A RIDGE ACROSS LAKE SUPERIOR ON
SUNDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER STORM WARNING UNTIL 7 PM EST /6 PM CST/ THIS EVENING FOR
MIZ005-006-011>013.
WINTER WEATHER ADVISORY UNTIL 7 PM EST /6 PM CST/ THIS EVENING
FOR MIZ004-007-010-014-085.
WINTER WEATHER ADVISORY UNTIL 4 PM EST /3 PM CST/ THIS AFTERNOON
FOR MIZ002-009-084.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING UNTIL 7 PM EST FRIDAY FOR LSZ266.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...JLA
SHORT TERM...ROLFSON
LONG TERM...KF
AVIATION...ROLFSON
MARINE...KF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
707 AM EST THU JAN 30 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 545 AM EST THU JAN 30 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A CLOSED MID LEVEL LOW
OVER NRN ONTARIO. IN THE BAND OF DEEP LAYER FORCING ASSOCIATED WITH
FEATURE...RADAR IMAGERY HAS SHOWN GOOD RADAR RETURNS FOR THE LAST
FEW HRS OVER LAKE SUPERIOR EXTENDING INTO PORTIONS OF THE ERN FCST
AREA. LOW-LEVEL DRY AIR HAS PROBABLY PREVENTED MUCH SNOW FROM
REACHING THE GROUND...AND MDOT WEBCAM/WEATHER STATION AT SENEY
INDICATES NOT MUCH GOING ON THERE DESPITE RADAR RETURNS. FARTHER N
TOWARD GRAND MARAIS...HAVE TO BELIEVE THERE IS SNOW FALLING IN THAT
AREA BASED ON INTENSITY OF RADAR RETURNS. COLD FRONT ASSOCIATED WITH
ONTARIO SYSTEM IS PASSING ACROSS WRN LAKE SUPERIOR. TO THE W...
ATTENTION IS ON SHORTWAVE MOVING ACROSS THE NRN PLAINS. AT THE
SFC...A LOW PRES WAVE HAS DEVELOPED ALONG THE SE SD/NE NEBRASKA
BORDER. AS SHORTWAVE MOVES E...SFC WAVE WILL TRACK ALONG COLD FRONT
MOVING ACROSS UPPER MI TODAY...PRODUCING A WIDESPREAD SNOW FOR MUCH
OF UPPER MI.
MODEL GUIDANCE HAS DEFINITELY TRENDED N AND W WITH SNOW BAND THAT
WILL ACCOMPANY SHORTWAVE...AND PCPN AMOUNTS HAVE TRENED UP AS WELL.
OVERALL...A GOOD SNOW EVENT APPEARS TO BE SHAPING UP TODAY. RATHER
STRONG DEEP LAYER FORCING PER QVECTORS IS INDICATED TO SHIFT ACROSS
THE AREA IN CONCERT WITH A BAND OF LOW-MID FRONTOGENESIS. AT THE
UPPER LEVELS...THERE ARE INDICATIONS OF SOME UPPER JET COUPLING BTWN
THE RIGHT ENTRANCE OF JET ASSOCIATED WITH NRN ONTARIO MID LEVEL LOW
AND LEFT EXIT OF JET ASSOCIATED WITH APPROACHING SHORTWAVE. THIS
COMES TOGETHER RIGHT OVER UPPER MI. MIXING RATIOS OF 2G/KG ARE NOTED
AROUND 700MB...SUGGESTING POTENTIAL FOR AROUND 4 INCHES OF SNOW.
HOWEVER...GIVEN SOME OF THE FORCING MECHANISMS NOTED ABOVE...
DEFINITELY HAVE CONCERN THAT AMOUNTS COULD REACH 6 INCHES OR
MORE...ESPECIALLY IF FOCUSED FRONTOGENETICAL FORCING DEVELOPS. SOME
HIGH RES MODEL GUIDANCE SUGGESTS THIS POTENTIAL COULD OCCUR ROUGHLY
ALONG AN AXIS FROM IRON RIVER TO MARQUETTE. HOURLY RUC13 MODEL RUNS
HAVE BEEN BEEFING UP PCPN AMOUNTS. 09Z RUN HAS AROUND 0.5 INCHES
ALONG THE AXIS MENTIONED. WILL BE SOMETHING TO MONITOR AS THE SNOW
AREA BECOMES ORGANIZED AND MORE INTENSE WHILE MOVING INTO UPPER MI.
HAVE EXPANDED WINTER WX ADVY TO COVER ALL BUT NRN HOUGHTON/KEWEENAW
COUNTIES TODAY. FORTUNATELY...THE STRONG WINDS NOW OCCURRING
DOWNWIND OF LAKE MI WILL BE SUBSIDING AS THE HEAVIER SNOW ARRIVES.
IN THE END...BLSN MAY NOT BE MUCH OF A PLAYER ANYWHERE DURING THE
MAIN PERIOD OF SNOWFALL. FOR SNOWFALL...EXPECT A GENERAL 3 TO 5 INCH
SNOWFALL ACROSS THE ADVY AREA WITH THE HEAVIEST SNOW PROBABLY IN A
WSW TO ENE BAND FROM ERN GOGEBIC/IRON/DICKINSON COUNTIES TO
BARAGA/MARQUETTE/ALGER COUNTIES.
SNOW WILL QUICKLY WIND DOWN/END FROM W TO E MID AFTN TO EARLY
EVENING. WNW TO W FLOW LES WILL FOLLOW TONIGHT AS 850MB TEMPS FALL
TO -16 TO -20C. HOWEVER...SHARP DROP OF INVERSION TO 3-4KFT COMBINED
WITH DRIER AIR SHOULD GREATLY LIMIT INTENSITY OF LES. ICE COVER ON
LAKE SUPERIOR WILL BE NEGATIVE FACTOR AS WELL. TEMPS ARE TRICKY. IF
WIND DECOUPLE AND CLOUD COVER CLEARS OUT SUFFICIENTLY...TEMPS WILL
PLUMMET AWAY FROM LAKE EFFECT AREAS. TRADITIONAL COLD SPOTS COULD
EASILY FALL WELL DOWN INTO THE -20S. FCST REFLECTS A CONSERVATIVE
APPROACH WITH TEMPS MAINLY IN THE SINGLE DIGITS TO LOW TEENS BELOW
ZERO. TEMPS SHOULD STAY ABOVE ZERO OVER THE FAR NE FCST AREA. WIND
CHILL MAY BE NEAR ADVY CRITERIA OVER PORTIONS OF THE W LATE
TONIGHT.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 519 AM EST THU JAN 30 2014
WILL START OUT WITH MAINLY ZONAL FLOW ALOFT FRIDAY MORNING. THAT
WILL QUICKLY CHANGE TO SW FLOW FRIDAY EVENING IN RESPONSE TO THE
MAIN 500MB LOW SHIFTING INTO N HUDSON BAY/QUEBEC...AND THE NEXT WAVE
SINKING IN FROM ONTARIO. QUICKENED THE END TO THE LIKELY POPS OVER
THE KEWEENAW PENINSULA...AND NEAR/EAST OF GRAND MARAIS FRIDAY AS SFC
WINDS BECOME MORE SW-W CUTTING OFF THE FLOW OF LINGERING MOISTURE
OFF LAKE SUPERIOR. HIGH TEMPS WILL STRUGGLE TO RISE INTO THE DOUBLE
DIGITS ABOVE ZERO FRIDAY...AND DEPENDING ON THE EXTENT OF ICE
COVERAGE OVER W LAKE SUPERIOR...MAY REMAIN IN THE LOW SINGLE DIGITS
ABOVE ZERO ACROSS THE W THIRD OF THE CWA.
GIVEN LOWS BOTTOMING OUT IN THE -10 TO 0 RANGE FRIDAY NIGHT/SATURDAY
MORNING...COULD HAVE A FEW POCKETS OF NEAR 20F WIND CHILL READINGS
OVER THE W HALF OF THE CWA...EVEN WITH LIGHT WINDS AVERAGING 5KTS OR
LESS. ALTHOUGH THERE WILL BE A COUPLE OF PERIODS OF WIND CHILL
VALUES IN THE 15-20 DEGREE RANGE...WILL LEAVE IT OUT OF THE HWO FOR
NOW...PARTICULARLY IN THE EXTENDED PERIOD WHERE OUR WIND FCST TENDS
TO BE TOO HIGH TO BEGIN WITH.
THE SW TO NE ORIENTED 500MB TROUGH SET UP FROM UT/CO TO FAR SE
MANITOBA SATURDAY AFTERNOON WILL SWEEP ACROSS THE UPPER GREAT LAKES
SATURDAY NIGHT INTO EARLY SUNDAY. CUT BACK ON THE S STREAM SLIGHT
CHANCE TO CHANCE POPS FOR SATURDAY AFTERNOON AND EVENING OVER THE S
AND E CWA. FCST MODELS LOOK TO BE CONSOLIDATING ON A SFC LOW TRACK
FROM N TX SATURDAY MORNING TO S/CENTRAL IL AT 18Z..AND N IN TO THE
LOWER GREAT LAKES AT 00Z SUNDAY. WHILE SOME SNOW WILL BE POSSIBLE ON
THE BACK SIDE OF THIS LOW SATURDAY AFTERNOON AND EARLY EVENING...IT
LOOKS LIKE THE BEST CHANCE WILL REMAIN TO OUR SE.
COLDER AIR SLIDING IN HOWEVER WILL BRING BACK A CHANCE OF LES TO THE
W FROM SATURDAY AFTERNOON...ON NW TO WNW WINDS AS 850MB TEMPS SLIDE
BACK INTO THE -15 TO -20C RANGE. WILL NOT GO TOO HIGH ON POPS FOR
SATURDAY AFTERNOON ON LES WISE...AS NOTED ABOVE...IT WILL GREATLY
DEPEND ON THE EXTENT OF ICE COVER ACROSS LAKE SUPERIOR. NO
SIGNIFICANT SNOW OR EXTREME /WIND CHILL WARNING/ COLD EVENTS ARE
FIGURED THROUGH THE REST OF THE PERIOD. THE NEXT POTENTIAL FOR
SYSTEM SNOW WILL ONCE AGAIN CLIP US TO THE S TUESDAY NIGHT AS THE
SFC LOW TRACKS UP THE OH VALLEY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 706 AM EST THU JAN 30 2014
A DISTURBANCE MOVING ALONG A COLD FRONT PUSHING ACROSS UPPER MI WILL
BRING SNOW TO THE AREA TODAY. EXPECT IFR CONDITIONS TO DEVELOP AT
KIWD/KCMX/KSAW MID TO LATE MORNING. HEAVIER SNOW IS EXPECTED TO
IMPACT KSAW...RESULTING IN SEVERAL HRS OF LIFR CONDITIONS. AFTER
THE DISTURBANCE DEPARTS...MVFR WX WILL RETURN. BEST CHC FOR MORE
PERSISTENT SHSN/IFR VIS WILL BE AT THE MORE EXPOSED KCMX LOCATION
WITH WNW FLOW BEHIND FROPA PRESENTING AN UPSLOPE WIND COMPONENT...
BUT ICE COVERAGE OVER WRN LAKE SUPERIOR MIGHT LIMIT THE
COVERAGE/INTENSITY OF THESE SHSN. DOWNSLOPE NATURE OF THIS FLOW WILL
RESULT IN VFR CONDITIONS DEVELOPING AT KSAW THIS EVENING. VFR
CONDITIONS WILL RETURN TO KIWD OVERNIGHT IF NOT SOONER AS WINDS BACK
SOME.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 256 AM EST THU JAN 30 2014
GALE FORCE GUSTS TO 35 KNOTS WILL REMAIN POSSILE EARLY THIS MORNING
E. WHILE HEAVY FREEZING SPRAY WILL BE LIMITED ELSEHWERE DUE
SIGNIFICANT ICE COVERING THE WATER...HEAVY FREEZING SPRAY WILL
REMAIN A CONCERN OVER E PORTIONS OF LAKE SUPERIOR THROUGH FRIDAY. A
FEW GALE FORCE GUSTS WILL ALSO BE POSSIBLE TONIGHT.
A LOW OVER CENTRAL ONTARIO WILL SHIFT E OF JAMES BAY THIS
EVENING...PULLING A TROUGH ACROSS LAKE SUPERIOR TODAY. HIGH PRESSURE
WILL THEN MOVE SE FROM ALBERTA TO S WI BY FRIDAY...WHILE BRINGING A
WEAK RIDGE OVER LAKE SUPERIOR. THEN ON SATURDAY...A TROUGH WILL MOVE
E ACROSS THE UPPER GREAT LAKES. THIS WILL BE FOLLOWED BY A HIGH OVER
THE MID MS VALLEY...WHICH WILL PASS A RIDGE ACROSS LAKE SUPERIOR ON
SUNDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER WEATHER ADVISORY UNTIL 7 PM EST /6 PM CST/ THIS EVENING
FOR MIZ004>007-010>014-085.
WINTER WEATHER ADVISORY UNTIL 4 PM EST /3 PM CST/ THIS AFTERNOON
FOR MIZ002-009-084.
LAKE SUPERIOR...
GALE WARNING UNTIL 10 AM EST THIS MORNING FOR LSZ266-267.
HEAVY FREEZING SPRAY WARNING UNTIL 7 PM EST FRIDAY FOR LSZ266.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...KF
AVIATION...ROLFSON
MARINE...KF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
545 AM EST THU JAN 30 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 545 AM EST THU JAN 30 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A CLOSED MID LEVEL LOW
OVER NRN ONTARIO. IN THE BAND OF DEEP LAYER FORCING ASSOCIATED WITH
FEATURE...RADAR IMAGERY HAS SHOWN GOOD RADAR RETURNS FOR THE LAST
FEW HRS OVER LAKE SUPERIOR EXTENDING INTO PORTIONS OF THE ERN FCST
AREA. LOW-LEVEL DRY AIR HAS PROBABLY PREVENTED MUCH SNOW FROM
REACHING THE GROUND...AND MDOT WEBCAM/WEATHER STATION AT SENEY
INDICATES NOT MUCH GOING ON THERE DESPITE RADAR RETURNS. FARTHER N
TOWARD GRAND MARAIS...HAVE TO BELIEVE THERE IS SNOW FALLING IN THAT
AREA BASED ON INTENSITY OF RADAR RETURNS. COLD FRONT ASSOCIATED WITH
ONTARIO SYSTEM IS PASSING ACROSS WRN LAKE SUPERIOR. TO THE W...
ATTENTION IS ON SHORTWAVE MOVING ACROSS THE NRN PLAINS. AT THE
SFC...A LOW PRES WAVE HAS DEVELOPED ALONG THE SE SD/NE NEBRASKA
BORDER. AS SHORTWAVE MOVES E...SFC WAVE WILL TRACK ALONG COLD FRONT
MOVING ACROSS UPPER MI TODAY...PRODUCING A WIDESPREAD SNOW FOR MUCH
OF UPPER MI.
MODEL GUIDANCE HAS DEFINITELY TRENDED N AND W WITH SNOW BAND THAT
WILL ACCOMPANY SHORTWAVE...AND PCPN AMOUNTS HAVE TRENED UP AS WELL.
OVERALL...A GOOD SNOW EVENT APPEARS TO BE SHAPING UP TODAY. RATHER
STRONG DEEP LAYER FORCING PER QVECTORS IS INDICATED TO SHIFT ACROSS
THE AREA IN CONCERT WITH A BAND OF LOW-MID FRONTOGENESIS. AT THE
UPPER LEVELS...THERE ARE INDICATIONS OF SOME UPPER JET COUPLING BTWN
THE RIGHT ENTRANCE OF JET ASSOCIATED WITH NRN ONTARIO MID LEVEL LOW
AND LEFT EXIT OF JET ASSOCIATED WITH APPROACHING SHORTWAVE. THIS
COMES TOGETHER RIGHT OVER UPPER MI. MIXING RATIOS OF 2G/KG ARE NOTED
AROUND 700MB...SUGGESTING POTENTIAL FOR AROUND 4 INCHES OF SNOW.
HOWEVER...GIVEN SOME OF THE FORCING MECHANISMS NOTED ABOVE...
DEFINITELY HAVE CONCERN THAT AMOUNTS COULD REACH 6 INCHES OR
MORE...ESPECIALLY IF FOCUSED FRONTOGENETICAL FORCING DEVELOPS. SOME
HIGH RES MODEL GUIDANCE SUGGESTS THIS POTENTIAL COULD OCCUR ROUGHLY
ALONG AN AXIS FROM IRON RIVER TO MARQUETTE. HOURLY RUC13 MODEL RUNS
HAVE BEEN BEEFING UP PCPN AMOUNTS. 09Z RUN HAS AROUND 0.5 INCHES
ALONG THE AXIS MENTIONED. WILL BE SOMETHING TO MONITOR AS THE SNOW
AREA BECOMES ORGANIZED AND MORE INTENSE WHILE MOVING INTO UPPER MI.
HAVE EXPANDED WINTER WX ADVY TO COVER ALL BUT NRN HOUGHTON/KEWEENAW
COUNTIES TODAY. FORTUNATELY...THE STRONG WINDS NOW OCCURRING
DOWNWIND OF LAKE MI WILL BE SUBSIDING AS THE HEAVIER SNOW ARRIVES.
IN THE END...BLSN MAY NOT BE MUCH OF A PLAYER ANYWHERE DURING THE
MAIN PERIOD OF SNOWFALL. FOR SNOWFALL...EXPECT A GENERAL 3 TO 5 INCH
SNOWFALL ACROSS THE ADVY AREA WITH THE HEAVIEST SNOW PROBABLY IN A
WSW TO ENE BAND FROM ERN GOGEBIC/IRON/DICKINSON COUNTIES TO
BARAGA/MARQUETTE/ALGER COUNTIES.
SNOW WILL QUICKLY WIND DOWN/END FROM W TO E MID AFTN TO EARLY
EVENING. WNW TO W FLOW LES WILL FOLLOW TONIGHT AS 850MB TEMPS FALL
TO -16 TO -20C. HOWEVER...SHARP DROP OF INVERSION TO 3-4KFT COMBINED
WITH DRIER AIR SHOULD GREATLY LIMIT INTENSITY OF LES. ICE COVER ON
LAKE SUPERIOR WILL BE NEGATIVE FACTOR AS WELL. TEMPS ARE TRICKY. IF
WIND DECOUPLE AND CLOUD COVER CLEARS OUT SUFFICIENTLY...TEMPS WILL
PLUMMET AWAY FROM LAKE EFFECT AREAS. TRADITIONAL COLD SPOTS COULD
EASILY FALL WELL DOWN INTO THE -20S. FCST REFLECTS A CONSERVATIVE
APPROACH WITH TEMPS MAINLY IN THE SINGLE DIGITS TO LOW TEENS BELOW
ZERO. TEMPS SHOULD STAY ABOVE ZERO OVER THE FAR NE FCST AREA. WIND
CHILL MAY BE NEAR ADVY CRITERIA OVER PORTIONS OF THE W LATE
TONIGHT.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 519 AM EST THU JAN 30 2014
WILL START OUT WITH MAINLY ZONAL FLOW ALOFT FRIDAY MORNING. THAT
WILL QUICKLY CHANGE TO SW FLOW FRIDAY EVENING IN RESPONSE TO THE
MAIN 500MB LOW SHIFTING INTO N HUDSON BAY/QUEBEC...AND THE NEXT WAVE
SINKING IN FROM ONTARIO. QUICKENED THE END TO THE LIKELY POPS OVER
THE KEWEENAW PENINSULA...AND NEAR/EAST OF GRAND MARAIS FRIDAY AS SFC
WINDS BECOME MORE SW-W CUTTING OFF THE FLOW OF LINGERING MOISTURE
OFF LAKE SUPERIOR. HIGH TEMPS WILL STRUGGLE TO RISE INTO THE DOUBLE
DIGITS ABOVE ZERO FRIDAY...AND DEPENDING ON THE EXTENT OF ICE
COVERAGE OVER W LAKE SUPERIOR...MAY REMAIN IN THE LOW SINGLE DIGITS
ABOVE ZERO ACROSS THE W THIRD OF THE CWA.
GIVEN LOWS BOTTOMING OUT IN THE -10 TO 0 RANGE FRIDAY NIGHT/SATURDAY
MORNING...COULD HAVE A FEW POCKETS OF NEAR 20F WIND CHILL READINGS
OVER THE W HALF OF THE CWA...EVEN WITH LIGHT WINDS AVERAGING 5KTS OR
LESS. ALTHOUGH THERE WILL BE A COUPLE OF PERIODS OF WIND CHILL
VALUES IN THE 15-20 DEGREE RANGE...WILL LEAVE IT OUT OF THE HWO FOR
NOW...PARTICULARLY IN THE EXTENDED PERIOD WHERE OUR WIND FCST TENDS
TO BE TOO HIGH TO BEGIN WITH.
THE SW TO NE ORIENTED 500MB TROUGH SET UP FROM UT/CO TO FAR SE
MANITOBA SATURDAY AFTERNOON WILL SWEEP ACROSS THE UPPER GREAT LAKES
SATURDAY NIGHT INTO EARLY SUNDAY. CUT BACK ON THE S STREAM SLIGHT
CHANCE TO CHANCE POPS FOR SATURDAY AFTERNOON AND EVENING OVER THE S
AND E CWA. FCST MODELS LOOK TO BE CONSOLIDATING ON A SFC LOW TRACK
FROM N TX SATURDAY MORNING TO S/CENTRAL IL AT 18Z..AND N IN TO THE
LOWER GREAT LAKES AT 00Z SUNDAY. WHILE SOME SNOW WILL BE POSSIBLE ON
THE BACK SIDE OF THIS LOW SATURDAY AFTERNOON AND EARLY EVENING...IT
LOOKS LIKE THE BEST CHANCE WILL REMAIN TO OUR SE.
COLDER AIR SLIDING IN HOWEVER WILL BRING BACK A CHANCE OF LES TO THE
W FROM SATURDAY AFTERNOON...ON NW TO WNW WINDS AS 850MB TEMPS SLIDE
BACK INTO THE -15 TO -20C RANGE. WILL NOT GO TOO HIGH ON POPS FOR
SATURDAY AFTERNOON ON LES WISE...AS NOTED ABOVE...IT WILL GREATLY
DEPEND ON THE EXTENT OF ICE COVER ACROSS LAKE SUPERIOR. NO
SIGNIFICANT SNOW OR EXTREME /WIND CHILL WARNING/ COLD EVENTS ARE
FIGURED THROUGH THE REST OF THE PERIOD. THE NEXT POTENTIAL FOR
SYSTEM SNOW WILL ONCE AGAIN CLIP US TO THE S TUESDAY NIGHT AS THE
SFC LOW TRACKS UP THE OH VALLEY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1217 AM EST THU JAN 30 2014
GUSTY S-SW WINDS EARLY IN ADVANCE OF AN APRCHG COLD FNT WILL
DIMINISH BY SUNRISE WITH THE ARRIVAL OF A WEAKER PRES GRADIENT.
SINCE THIS SSW FLOW IS FAIRLY DRY...VFR CONDITIONS SHOULD
PREDOMINATE UNTIL THE COLD FNT ARRIVES. A DISTURBANCE MOVING ALONG
THE COLD FNT WL THEN BRING A PERIOD OF -SN TO UPR MI THIS MRNG INTO THE
AFTN...RESULTING IN IFR CONDITIONS. AFTER THIS DISTURBANCE
DEPARTS...MVFR WX WL RETURN. BEST CHC FOR MORE PERSISTENT SHSN/IFR
VSBYS WL BE AT THE MORE EXPOSED CMX LOCATION WITH WNW FLOW BEHIND THE
FROPA PRESENTING AN UPSLOPE WIND COMPONENT...BUT ICE COVERAGE OVER
WRN LK SUP MIGHT LIMIT THE COVERAGE/INTENSITY OF THESE SHSN.
DOWNSLOPE NATURE OF THIS FLOW WL RESULT IN VFR CONDITIONS AT SAW THIS
EVNG.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 256 AM EST THU JAN 30 2014
GALE FORCE GUSTS TO 35 KNOTS WILL REMAIN POSSILE EARLY THIS MORNING
E. WHILE HEAVY FREEZING SPRAY WILL BE LIMITED ELSEHWERE DUE
SIGNIFICANT ICE COVERING THE WATER...HEAVY FREEZING SPRAY WILL
REMAIN A CONCERN OVER E PORTIONS OF LAKE SUPERIOR THROUGH FRIDAY. A
FEW GALE FORCE GUSTS WILL ALSO BE POSSIBLE TONIGHT.
A LOW OVER CENTRAL ONTARIO WILL SHIFT E OF JAMES BAY THIS
EVENING...PULLING A TROUGH ACROSS LAKE SUPERIOR TODAY. HIGH PRESSURE
WILL THEN MOVE SE FROM ALBERTA TO S WI BY FRIDAY...WHILE BRINGING A
WEAK RIDGE OVER LAKE SUPERIOR. THEN ON SATURDAY...A TROUGH WILL MOVE
E ACROSS THE UPPER GREAT LAKES. THIS WILL BE FOLLOWED BY A HIGH OVER
THE MID MS VALLEY...WHICH WILL PASS A RIDGE ACROSS LAKE SUPERIOR ON
SUNDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER WEATHER ADVISORY UNTIL 7 PM EST /6 PM CST/ THIS EVENING
FOR MIZ004>006-010>013.
WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR MIZ007-
014-085.
WINTER WEATHER ADVISORY UNTIL 4 PM EST /3 PM CST/ THIS AFTERNOON
FOR MIZ002-009-084.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST THIS MORNING FOR
LSZ267.
GALE WARNING UNTIL 10 AM EST THIS MORNING FOR LSZ266-267.
HEAVY FREEZING SPRAY WARNING UNTIL 7 PM EST FRIDAY FOR LSZ266.
LAKE MICHIGAN...
HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST THIS MORNING FOR
LMZ248-250.
GALE WARNING UNTIL 6 AM EST EARLY THIS MORNING FOR LMZ248-250.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...KF
AVIATION...ROLFSON
MARINE...KF
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
607 AM CST THU JAN 30 2014
.UPDATE...
12Z AVIATION DISCUSSION ADDED BELOW.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 403 AM CST THU JAN 30 2014
FAST MOVING...THOUGH HARD HITTING SNOW STORM STILL ON TRACK TO
IMPACT THE AREA THIS MORNING. EVENING SHIFT LAST NIGHT DID AN
EXCELLENT JOB IN RAMPING UP POPS/QPF/SNOW AMOUNTS FOR THIS EVENT
WITH ONLY MINOR TWEAKS MADE TO THE GRIDS OVERNIGHT TO SLOW DOWN THE
ONSET OF SNOW ALONG WITH ITS DEPARTURE ALONG WITH NARROWING THE
SWATH OF HEAVIEST SNOW/QPF TO REFLECT WHAT IS SEEN WITH THE
HRRR/HOPWRF/RAP...WHICH ARE NEARLY LAYING ON TOP OF EACH OTHER WITH
ABOUT A 50 MILE WIDE BAND OF QPF GREATER THAN A QUARTER INCH
STRETCHING FROM MONTEVIDEO...TO THE NRN TWIN CITIES METRO AND OVER
TO LADYSMITH. WITHIN THIS BAND...CURRENT GRIDS HAVE SNOW AMOUNTS
BETWEEN 4 AND 6 INCHES OF SNOW. YOU GET OUT OF THIS BAND AND AMOUNTS
WILL FALL OFF QUICKLY...WITH JUST 1-3 INCHES CURRENTLY PREDICTED FOR
THE REST OF THE CWA. LOOKING AT THE HEADLINES...THEY STILL LOOK TO
BE IN GOOD SHAPE...THOUGH DID TOSS AROUND THE IDEA OF EXTENDING THE
WARNING DUE WEST FROM IT/S CURRENT LOCATION OUT TO THE SODAK
BORDER. THOUGH WARNING TYPE SNOWS /6 INCHES OR MORE/ WILL BE
ISOLATED...AS THE EVENING SHIFT POINTED OUT...THE SEVERE IMPACTS TO
THE MORNING COMMUTE KEEP THIS A WARRANTED WARNING.
LOOKING AT WHAT IS HAPPENING NOW...A 150 JET STREAK IS CURRENTLY
WORKING ACROSS NRN NEB. TO THE NORTH OF THIS...A POTENT H4 PV
ANOMALY IS MOVING ACROSS SODAK. UPPER DIVERGENCE OUT AHEAD OF THE PV
FEATURE AND WITHIN THE LEFT EXIT REGION OF THE UPPER JET HAS LED TO
A SIGNIFICANT INCREASE IN H85-H7 WINDS ACROSS ERN NEB TO UP OVER 60
KTS. THIS IS RESULTING IN INTENSE ISENTROPIC LIFT OVER AN ARCTIC
BOUNDARY THAT AT 3 AM STRETCHED FROM A 992 MB SFC LOW NEAR SIOUX
FALLS UP THROUGH THE TWIN CITIES. THIS ISENTROPIC LIFT /ON THE 295 K
SFC/ IS RUNNING RIGHT INTO A STRENGTHENING BAND OF FGEN THAT HAS
BEEN MOST EVIDENT BY THE SLOWLY DESCENDING CIGS FROM WEST CENTRAL MN
OVER TO THE US-8 CORRIDOR IN WI. THIS FGEN BAND HAS BEEN SPENDING A
COUPLE OF HOURS MOISTENING THE ATMO AND WE ARE BEGINNING TO SEE
THOSE EFFORTS PAY OFF...WITH SNOW RAPIDLY EXPANDING ALONG THE FGEN
AFTER ABOUT 230 THIS MORNING. WITH ALL OF THIS HAPPENING...BEST LI/S
OFF THE NAM ARE DOWN AROUND +5...INDICATIVE OF AN ATMOSPHERE WITH
WEAK STABILITY AND PRIMED FOR MESOSCALE BANDING...WHICH IS EXACTLY
WHAT HAVE HAVE BEEN SEEING ON THE KABR RADAR SINCE ABOUT 7Z. WILL BE
INTERESTING TO SEE HOW THIS PLAYS OUT THIS MORNING...AS THE RAP
ALONG WITH SOME OF THE HOPWRF MEMBERS HAVE BEEN PUMPING OUT SNOWFALL
TOTALS IN EXCESS OF 8 INCHES WITHIN THE HEART OF THE BAND.
THIS SNOW WILL BE OUT OF THE AREA QUICKLY BY THIS AFTERNOON...WITH
CLOUDS LOOKING TO DEPART WITH THE SNOW AS WELL. NW WINDS IN THE WAKE
OF THE FRONT AND SNOW THIS AFTERNOON WILL RESULT IN TEMPS SLOWLY
FALLING ALL AFTERNOON. FOR THOSE WINDS...WE MAY SEE SOME GUSTS UP
AROUND 30 MPH DOWN THE MN RIVER VALLEY INTO SOUTH CENTRAL MN THIS
AFTERNOON...ENOUGH TO MAKE IT FEEL UNCOMFORTABLE AGAIN...BUT NOT
ENOUGH TO RESULT IN SIGNIFICANT BLOWING SNOW ISSUES TO WARRANT
KEEPING ANY HEADLINES GOING BEHIND THE SNOW.
TONIGHT...HIGH PRESSURE ARRIVES FROM CANADA...AS DO TEMPERATURES
BACK BELOW ZERO. HAVE LOWS TONIGHT RUNNING AROUND -20 IN CENTRAL
MN...-10 IN THE TWIN CITIES AND AROUND -5 ALONG THE I-90 CORRIDOR.
TACK ON WINDS UP IN THE 5-10 MPH RANGE AND END UP WITH YET ANOTHER
NIGHT WHERE WIND CHILL VALUES FALL TO BETWEEN 25 AND 35 BELOW ZERO
AND YET ANOTHER WIND CHILL ADVY. DECIDED JUST TO GET THE INEVITABLE
OVER WITH AND ISSUED THE NEXT WIND CHILL ADVY FOR OUR EVER GROWING
STACK. FOR NOW..JUST ISSUED IT FOR THE ENTIRE CWA...BUT IT IS A BIT
MORE IFFY DOWN TOWARD SW MN AND THE IA BORDER...SO THE DAY SHIFT CAN
ALWAYS TRIM SOME COUNTIES OFF IF NEED BE.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 403 AM CST THU JAN 30 2014
NO SIGNIFICANT CHGS FOR THE EXTENDED PERIOD WITH THE POSITIVE
LONG-WAVE TROUGH ACROSS THE ROCKIES...AND NORTHEAST ACROSS THE
EASTERN 3/4 OF CANADA. THE ONLY NOTABLE CHGS IN THE UPPER FLOW
COMPARED TO THE PAST FEW WEEKS IS THE INCREASE IN THE RIDGE IN THE
SE U.S. THE MEAN FLOW FROM 85-50H REMAINS FROM THE NORTH POLE SO THE
CONTINUED REINFORCING SHOTS OF ARCTIC AIR MASSES WILL REMAIN THRU
NEXT WEEK. THE ACTIVE WX WILL REMAIN SOUTH OF THE CWA DUE TO THE
ORIENTATION OF THE LONG-WAVE TROUGH AND THE SOUTHERN JET ANCHORED
ACROSS THE EASTERN U.S. ALTHOUGH MOST OF THE EXTENDED PERIOD WILL BE
DRY...SLIGHT CHC/S OF FLURRIES/-SN WILL ACCOMPANY SATURDAY/S WEAK
FRONTAL BOUNDARY...AND AGAIN EARLY NEXT WEEK. STANDARDIZED ANOMALIES
REMAIN CLOSE TO SEASONABLE NORMS...SO ANY ARCTIC OUTBREAKS SHOULDN/T
BE AS BAD AS IN THE FIRST THREE WEEKS OF JAN. HOWEVER...I DON/T WANT
TO DOWNPLAY THE COLDER WIND CHILL VALUES AS SEVERAL TIMES IN THE
COURSE OF SUN/WED OF NEXT WEEK...READINGS WILL FALL BLW -25F.
LONGER RANGE MODELS HAVE NOT DEVIATED FROM THE CURRENT LONG-WAVE
PATTERN THRU THE MIDDLE OF FEB. UNTIL THIS PATTERN CHGS...BLW NORMAL
TEMPS WILL CONTINUE ACROSS THE UPPER MIDWEST.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 607 AM CST THU JAN 30 2014
SNOW STARTING TO RAMP UP ACROSS THE AREA THIS MORNING IN RESPONSE
TO A SFC LOW OVER NE IOWA AND A COLD FRONT STRETCHED OUT FROM FRM
TO THE SE TWIN CITIES METRO AND RICE LAKE. SNOW HAS BEEN HEAVIEST
BEHIND THE COLD FRONT...THOUGH TO THIS POINT VSBYS HAVE BEEN SLOW
TO GO BELOW 1SM. HOWEVER...CIGS HAVE TUMBLED TO UNDER 500 FT FOR
MANY AREAS...SO THINK VIS WILL BE SOON TO FOLLOW. WHERE SNOW BROKE
OUT FIRST WILL LIKELY BE WHERE 5-6 INCH TOTALS ARE LIKELY THIS
MORNING...WHICH MEANS RWF/MSP/RNH WILL BE GETTING THE DIRECT
IMPACTS FROM THIS SNOW. CURRENT TAFS REFLECTED CONDITIONS QUITE
WELL...SO DID NOT MAKE TOO MANY CHANGES. ABOUT THE ONLY CHANGE IN
EXISTING TAFS WAS TO REMOVE TEMPO 1/4SM GROUPS AS VSBYS HAVE BEEN
SLOW TO RESPOND. ALSO HAD TO HOLD ON TO SOME LIGHT SNOW IN WRN WI
A LITTLE LONGER. STILL LOOKS GOOD FOR QUICK IMPROVEMENTS TO VFR IN
THE WAKE OF THE SNOW WITH SKIES CLEARING OUT.
KMSP...STARTED OUT WITH 1/2SM VIS...THOUGH MAY TAKE TO AS LATE AS
13Z TO GET THERE. AT ANY RATE...WITH MIC ALREADY THERE AND OTHER
AIRPORTS IN THE REGION DROPPING QUICKLY...DECIDED TO JUST COME OUT
THE GATES FIRING WITH THE VIS. WILL BE FAST MOVING...AND HAVE BEEN
FOLLOWING THE HRRR ALL MORNING FOR PUSHING THE SNOW OUT...WHICH
HAS BEEN PRETTY STABLE...ALONG WITH MATCHING TRENDS TO THE WEST.
WITH THE BAND LOOKING TO SET UP RIGHT OVER MSP...GAINING
CONFIDENCE IN MSP SEEING THE HIGHER END OF SNOW TOTALS UP IN THE
AREA OF 5 INCHES.
/OUTLOOK FOR KMSP/
FRI...VFR. WINDS WSW 5 KTS.
SAT...VFR. WINDS SW 5KTS EARLY BCMG NW AT 10G15KTS.
SUN...VFR. WINDS W BECOMING SW 5-10 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...WINTER WEATHER ADVISORY UNTIL NOON CST TODAY FOR MNZ041>045-
047>050-054>058-064-065-067-073>078-082>085-091>093.
WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 9 AM CST FRIDAY FOR
MNZ053-060>063-067>070-074>078-082>085-091>093.
WIND CHILL ADVISORY FROM 9 PM THIS EVENING TO 9 AM CST FRIDAY
FOR MNZ041>045-047>052-054>059-064>066-073.
WINTER STORM WARNING UNTIL NOON CST TODAY FOR MNZ051>053-059>063-
066-068>070.
WI...WINTER WEATHER ADVISORY UNTIL NOON CST TODAY FOR WIZ026-028.
WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 9 AM CST FRIDAY FOR
WIZ014>016-023>028.
WINTER STORM WARNING UNTIL NOON CST TODAY FOR WIZ014>016-023>025-
027.
&&
$$
SHORT TERM...MPG
LONG TERM...JLT
AVIATION...MPG
AREA FORECAST DISCUSSION
NWS RALEIGH NC
622 AM EST THU JAN 30 2014
.SYNOPSIS...MODIFIED ARCTIC HIGH PRESSURE WILL PERSIST OVER THE
CAROLINAS THROUGH TONIGHT. A RELATIVELY WARM AND MOIST SOUTHERLY
RETURN FLOW WILL PREVAIL FRIDAY INTO THE WEEKEND AS A COLD FRONT
SLOWLY APPROACHES THE REGION FROM THE WEST.
&&
.NEAR TERM /TODAY AND TONIGHT/...
AS OF 255 AM THURSDAY...
...WINTER WEATHER ADVISORY FOR ICE/BLACK ICE WILL CONTINUE THROUGH
NOON...
...ANOTHER WINTER WEATHER ADVISORY FOR BLACK ICE MAY BE NEEDED FOR
PORTIONS OF CENTRAL NC TONIGHT/FRI MORNING...
OVERVIEW: PER THE LATEST WV IMAGERY AND RAP DATA...A SHORTWAVE
TROUGH CENTERED OVER EASTERN TN AT 06Z WILL DEAMPLIFY AS IT LIFTS
ENE TO THE DELMARVA/MID-ATLANTIC COAST BY 18Z...PROGRESSING OFFSHORE
INTO THE ATLANTIC THEREAFTER. ANOTHER SHORTWAVE TROUGH APPROACHING
THE TX/LA GULF COAST AT 06Z WILL DEAMPLIFY AS IT TRACKS ESE/SE INTO
THE GOMEX THIS AFT/EVE...THEN EAST TOWARD THE FL GULF COAST BY 12Z
FRI. WEAK DPVA ASSOCIATED WITH A SHEAR AXIS EXTENDING NORTHWARD FROM
THE AFOREMENTIONED SHORTWAVE WILL TRACK EAST THROUGH THE REGION TO
THE CAROLINA COAST TONIGHT. MODIFIED ARCTIC HIGH PRESSURE WILL
PERSIST ACROSS THE CAROLINAS TODAY. AN ELONGATED SFC TROUGH WILL
PERSIST OFFSHORE THE CAROLINA COAST...IN A REGION OF STRONG
BAROCLINICITY BETWEEN THE AFOREMENTIONED ARCTIC AIRMASS AND THE GULF
STREAM. WEAK CYCLOGENESIS WILL LIKELY OCCUR ALONG PORTIONS OF THE
OFFSHORE TROUGH /BAROCLINIC ZONE/ TODAY AND TONIGHT IN ASSOCIATION
WITH WEAK DPVA ATTENDANT THE AFOREMENTIONED UPPER LEVEL FEATURES.
PRECIPITATION CHANCES: A VERY DRY ARCTIC AIRMASS IS IN PLACE INLAND
ACROSS CENTRAL NC TODAY (00Z GSO RAOB/PWAT 0.05"). UPPER LEVEL
MOISTURE INCREASES TOWARD THE COAST PER THE 00Z MHX RAOB AND 06Z
IR/WV SAT IMAGERY...THOUGH EVEN THERE THE LOWEST 10-15 KFT REMAIN
EXCEEDINGLY DRY. LOW-LEVEL WARM ADVECTION WILL STRENGTHEN OVER FAR
EASTERN PORTIONS OF THE STATE THIS AFTERNOON AND EARLY TONIGHT AS
WEAK DPVA ASSOC/W THE AFOREMENTIONED SHORTWAVE ENERGY APPROACHES THE
OFFSHORE SFC TROUGH /BAROCLINIC ZONE/. THE RELATIVELY WEAK AND
PROGRESSIVE NATURE OF THE AFOREMENTIONED UPPER LEVEL FEATURES WILL
RESULT IN A BRIEF WINDOW FOR MOISTURE RECOVERY ASSOCIATED WITH WARM
ADVECTION IN EASTERN NC...ESPECIALLY WITH A DRY ARCTIC AIRMASS IN
PLACE IN THE LOWEST 10-15 KFT. WITH THE ABOVE IN MIND...EXPECT ANY
CHANCE FOR PRECIPITATION TO REMAIN ALONG THE IMMEDIATE COAST /OBX/
OR (MORE LIKELY) ENTIRELY OFFSHORE...WHICH IS FORTUNATE GIVEN THAT
THE SURFACE WETBULB PROFILE WOULD SUPPORT FZRA.
TEMPERATURES: A VARIETY OF FACTORS WILL INFLUENCE HIGHS TODAY. WITH
SFC HIGH PRESSURE OVER THE CAROLINAS...EXPECT LITTLE OR NO SURFACE
ADVECTION. THOUGH CLEAR SKIES WILL LIKELY BE PRESENT WEST OF I-95...
BROKEN TO OVERCAST UPPER LEVEL CLOUD COVER (15+ KFT CEILINGS) WILL
BE PRESENT EAST OF I-95 THIS MORNING AS THE CIRRUS SHIELD OVER THE
EASTERN CAROLINAS EXPANDS WESTWARD IN RESPONSE TO THE SHORTWAVE
TRACKING ENE INTO THE MID-ATLANTIC. THE AFOREMENTIONED CIRRUS SHOULD
SHIFT EASTWARD BY MID MORNING (~15Z) AS THE SHORTWAVE TRACKS RAPIDLY
ENE TO THE DELMARVA...THOUGH AN APPROACHING SHEAR AXIS THIS
AFTERNOON COULD RETARD THE EASTWARD RETREAT OF THE CIRRUS SHIELD AND
ALLOW BKN/OVC SKIES TO PERSIST LONGER INTO THE PEAK HEATING CYCLE.
ADDITIONALLY...LOW-LEVEL CLOUD COVER (CEILINGS 2500-3500 FT AGL)
COULD DEVELOP IN ASSOC/W 925-850 MB WARM ADVECTION LATE THIS
AFTERNOON...THOUGH THAT WOULD BE MORE LIKELY AFTER PEAK HEATING. ON
TOP OF ALL OF THE ABOVE...SNOW COVER PERSISTS ACROSS THE REGION AND
WILL CERTAINLY AFFECT HIGHS...ESP EAST OF HIGHWAY 1 IN THE
CENTRAL/NE COASTAL PLAIN WHERE ACCUMULATIONS WERE THE HIGHEST (4-
6"). WITH THE ABOVE IN MIND...HAVE OPTED TO DECREASE HIGHS A FEW
DEGREES...ESP IN THE CENTRAL/NE COASTAL PLAIN WHERE SNOW COVER IS
GREATER AND INTERMITTENT CLOUD COVER MORE LIKELY. LOWS TONIGHT WILL
BE COMPLICATED BY POSSIBLE BROKEN/OVERCAST STRATUS IN THE COASTAL
PLAIN BETWEEN SUNSET-MIDNIGHT...THOUGH CLEARING IS LIKELY AFTER
MIDNIGHT AND TEMPS WOULD RAPIDLY FALL THEREAFTER...ESP WITH A
SNOWPACK PERSISTING IN THE CENTRAL/NE COASTAL PLAIN. EXPECT LOWS IN
THE MID/UPPER TEENS.
ANOTHER WINTER WEATHER ADVISORY FOR BLACK ICE MAY BE NEEDED FOR
PORTIONS OF THE AREA TONIGHT/FRI MORNING...ESPECIALLY IN LOCATIONS
THAT RECEIVED 4-6" OF SNOW (CENTRAL/NE COASTAL PLAIN) AND THAT ARE
LESS LIKELY TO EXPERIENCE COMPLETE MELTING. DUE TO THE ONGOING
ADVISORY IN EFFECT THROUGH NOON...AND THAT IF AND WHERE AN ADVISORY
IS ISSUED FOR TONIGHT WILL DEPEND ON AN ONGOING ASSESSMENT OF
CONDITIONS THROUGHOUT THE DAY...FEEL THAT IT IS MOST PRUDENT TO
ALLOW A DECISION TO BE MADE THIS AFTERNOON. -VINCENT
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY/...
AS OF 300 AM THURSDAY...
FRIDAY THROUGH SATURDAY...THE COLD RIDGE WILL SHIFT EAST WITH ONE
LAST COLD MORNING WITH RE-FREEZING SATURDAY OF WHAT DOES NOT MELT IN
SHADY AREAS. THE WARMING DURING THE DAY FOR SATURDAY AND SUNDAY
APPEARS THAT IT MAY BE INHIBITED BY THE EXPECTED WAA/MOIST AIR
ADVECTION PATTERN SURFACE AND ALOFT. THERE MAY EVEN BE SOME SPOTTY
LIGHT RAIN OVER THE WEEKEND. THIS OCCURS BEFORE THE NEXT WAVE OF LOW
PRESSURE IS FORECAST TO APPROACH THE REGION FROM THE LOWER
MISSISSIPPI VALLEY REGION SUNDAY AFTERNOON.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 300 AM THURSDAY...
ALTHOUGH A MUCH NEEDED THAW OUT IS EXPECTED THIS WEEKEND...QUESTION
MARKS REMAIN WITH CHANCES FOR PRECIPITATION LATE THIS WEEKEND
THROUGH MID NEXT WEEK.
THE THEME OF THE MODELS REMAINS A FORECAST MEAN MID/UPPER PATTERN
THAT CONSISTS OF A CLOSED UPPER CIRCULATION OVER HUDSON BAY ALONG
WITH THE DEVELOPMENT OF A WESTERN UNITED STATES TROUGH. AN EASTERN
PACIFIC SYSTEM IS STILL FORECAST TO PLOW INTO THE SOUTHWESTERN
STATES BY MONDAY...THEN TRACK OUT OVER THE PLAINS AND MISSISSIPPI
VALLEY BY TUE-WED. THE ENSEMBLE MEANS ARE PREFERRED OVER THE MAIN
OPERATIONAL MODELS PER WPC.
IT APPEARS THAT A COLD FRONT WILL TRY TO "BACKDOOR" OUR REGION
SUNDAY NIGHT AS THE WAVE OF LOW PRESSURE TRACKS NE OVER EASTERN NC
EARLY MONDAY... THEN OFF THE MID-ATLANTIC COAST MONDAY AFTERNOON.
THE TIMING OF THIS FRONT WILL BE CRITICAL IN THE FORECAST FOR
TEMPERATURES AS IT SHOULD BE DRIVEN BY A COLD SURFACE HIGH PRESSURE
OVER THE MID-WEST (1030+ MB). CURRENT ENSEMBLES SUGGEST THAT THE
MEAN TIMING WOULD PLACE THE BOUNDARY INTO SC BY 12Z MONDAY. IF THIS
OCCURS... P-TYPE WITH THIS SYSTEM MAY BECOME AN ISSUE. THE DEPTH AND
STRENGTH OF THE COLD AIR THIS FAR OUT IS TOO DIFFICULT TO FORECAST.
WE WILL MAINTAIN THE PREVIOUS FORECASTS CONTINUITY AND KEEP ALL
LIQUID FOR SUNDAY NIGHT INTO MONDAY. HOWEVER... HIGHS MAY STAY IN
THE 30S/40S MONDAY NORTH TO SOUTH.
YET ANOTHER STRONGER SYSTEM IS EXPECTED TO BRING RAIN BACK TO THE
REGION LATER TUESDAY AND WEDNESDAY. AGAIN... P-TYPE MAY BECOME MORE
OF A CONCERN IF THE COLD AIR DAMMING DEVELOPS PER SOME MODEL
SOLUTIONS... EVEN THOUGH THE MAIN STORM TRACK IS EXPECTED TO BE SW-
NE ALONG THE MOUNTAINS... WITH MILLER TYPE B SURFACE DEVELOPMENT
OFFSHORE THE MID-ATLANTIC WED. MUCH COLDER AND DRIER AIR AGAIN
EXPECTED WEDNESDAY NIGHT/THURSDAY. -BADGETT
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
AS OF 620 AM THURSDAY...
24 HOUR TAF PERIOD: VFR CONDITIONS WILL PREVAIL TODAY IN ASSOCIATION
WITH MODIFIED ARCTIC HIGH PRESSURE OVER THE CAROLINAS. PATCHY
FREEZING FOG WILL LINGER THROUGH 12-13Z AT LATEST AT THE RWI
TERMINAL BEFORE LIFTING AND SCATTERING OUT TO VFR. WITH SURFACE HIGH
PRESSURE OVER THE REGION...LIGHT/VARIABLE WINDS WILL PREVAIL THROUGH
THE TAF PERIOD. A LIGHT SOUTHERLY RETURN FLOW WILL DEVELOP IN THE
LOWER LEVELS THIS EVENING AND EARLY TONIGHT AS THE 925-850 MB RIDGE
MOVES OFFSHORE. IT IS POSSIBLE THAT MVFR (PERHAPS IFR) CEILINGS
COULD DEVELOP ACROSS EASTERN NC SHORTLY AFTER SUNSET AT THE
KFAY/KRWI TERMINALS...THOUGH MODEL GUIDANCE SHOWS ONLY A BRIEF
PERIOD OF WARM ADVECTION AND ANY SUB-VFR CEILINGS THAT DEVELOP WOULD
LIKELY DISSIPATE AFTER MIDNIGHT. WILL INCLUDE A TEMPO GROUP FOR MVFR
CEILINGS AT KFAY/RWI BETWEEN 00-04Z FRIDAY.
LOOKING AHEAD: VFR CONDITIONS WILL PREVAIL ON FRIDAY. SUB-VFR
CEILINGS ARE EXPECTED TO DEVELOP SAT AND PERSIST THROUGH THE WEEKEND
IN ASSOCIATION WITH AN INCREASINGLY MOIST SOUTHERLY RETURN FLOW IN
ADVANCE OF AN APPROACHING COLD FRONT. -VINCENT
&&
.CLIMATE...
RECORD LOWS FOR JANUARY 30TH
GSO 4 DEGREES SET IN 1966
RDU 7 DEGREES SET IN 1977
FAY 8 DEGREES SET IN 1934
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL NOON EST THURSDAY FOR NCZ007>011-
021>028-038>043-073>078-083>086-088-089.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...VINCENT
SHORT TERM...BADGETT
LONG TERM...BADGETT
AVIATION...VINCENT
CLIMATE...RAH
AREA FORECAST DISCUSSION
NWS SPOKANE WA
725 AM PST Thu Jan 30 2014
.SYNOPSIS...
Unsettled and cool conditions will persist today with occasional
snow showers mostly with minor accumulations. A drying and
clearing trend will begin Friday. No major storm systems are
expected for the next seven days...but a cooling trend is likely
by early next week.
&&
.DISCUSSION...
Quick update to forecast made for today to better account for the
snowfall generated in elongated narrow bands dropping down in a
slow north to south manner over Eastern Washington and Northern
Idaho per recent radar and satellite imagery. Using the trend in
the recent 12Z HRRR but only up to 20Z today cause it seems want
to decrease the shower activity somewhat at that point in time
which I don`t really agree with at the moment. /Pelatti
&&
.AVIATION...
12Z TAFS: A broad area of low pressure will remain over the
forecast area through 12Z Friday. The boundary layer is moist
under a nocturnal inversion and this will produce IFR conditions
at least temporarily this morning at most TAF sites. A cold front
will descend from the north and trigger SCT -SHSN during the
afternoon and evening over the KGEG area TAF sites and overnight
at the KPUW and KLWS TAF sites. The KMWH and KEAT TAF sites will
mostly escape these snow showers...and should break out to VFR
conditions during the afternoon. Drier air overnight tonight in
the wake of the cold front will limit fog Friday morning but
stratus layers may re-occur late tonight. /MJF
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 31 20 30 18 28 17 / 60 40 10 0 10 10
Coeur d`Alene 33 20 33 17 31 16 / 60 40 10 10 10 10
Pullman 35 26 34 24 33 21 / 50 50 40 10 10 10
Lewiston 39 30 39 27 38 23 / 50 50 30 10 10 10
Colville 32 20 32 13 30 10 / 70 20 10 0 10 10
Sandpoint 33 18 32 15 31 13 / 70 20 10 0 10 10
Kellogg 31 21 31 18 29 15 / 70 60 40 10 20 10
Moses Lake 35 25 35 21 34 20 / 20 40 10 0 10 0
Wenatchee 34 25 35 23 35 20 / 20 50 10 0 0 10
Omak 34 22 32 13 30 16 / 50 20 10 0 0 10
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Winter Storm Warning until 4 PM PST this afternoon for Central
Panhandle Mountains.
Winter Weather Advisory until 10 AM PST this morning for Lewis
and Southern Nez Perce Counties.
WA...None.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
524 AM CST THU JAN 30 2014
UPDATED TO ADD AVIATION AND MARINE SEGMENTS.
.TODAY...FORECAST CONFIDENCE IS MEDIUM.
IT WILL DEFINITELY BE WINDY AND THERE WILL BE ACCUMULATING SNOW
DURING THE MIDDLE PART OF THE DAY. BASED ON TRACKING OF THE MOVEMENT
OF HIGHER REFLECTIVITY SNOW ON AREA RADARS TO THE WEST...HAVE KEPT
CURRENT TIMING OF SNOW INTO THE WESTERN CWA AROUND 14Z-15Z...
REACHING BERLIN...MADISON AND MONROE AROUND 16Z...PLYMOUTH...
WAUKESHA AND LAKE GENEVA AROUND 17Z...AND MILWAUKEE TO KENOSHA BY
18Z.
SOME CONCERN WITH LATEST HRRR AND RAP THAT KEEP THE SNOW FROM
MADISON AND WEST THROUGH 18Z...SO WILL MONITOR OBS/RADAR AND ADJUST
IF NECESSARY. LEADING AREA OF RETURNS WITH STRONG ISENTROPIC LIFT
OVER SRN MN AND N CENTRAL IOWA...BUT NO GROUND TRUTH WITH 9-10K FT
CEILINGS REFLECTING DRY LAYER BELOW 10K FT ON FORECAST SOUNDINGS
THAT WILL HAVE TO SATURATE BEFORE SNOW REACHES GROUND.
HAVE DROPPED SNOW ACCUMULATIONS A BIT AS NOT QUITE AS MUCH QPF USING
CONSENSUS MODEL AMOUNTS...WHICH WERE HIGHER THAN WPC...WHICH KEEPS
SNOW TOTALS IN THE 1 TO 2 INCH RANGE WITH THE HIGHER AMOUNTS NORTH
WITH BETTER FRONTOGENETIC FORCING...THOUGH AN ISOLATED 3 INCH TOTAL
NOT OUT OF THE QUESTION.
WINDS WILL BE AN ISSUE MAINLY AHEAD OF...AND AT THE ONSET OF THE
SNOW WITH 45-50KT WINDS AT 900-925 MB AHEAD OF LOW. SOME BLOWING AND
DRIFTING EXPECTED WITH THE STRONG WINDS EARLY THIS MORNING...BUT
WITH CURRENT OBS REMAINING AT 10SM WITH GUSTS TO 30 KNOTS...THINK
DRIFTING ON EAST-WEST ROADS IN OPEN AREAS WILL BE THE BIGGER
PROBLEM.
FORECAST SOUNDINGS DO NOT REACH THESE STRONGEST WINDS WITH THE
INVERSION LIMITING MIXING UP TO AROUND 1K FT. THIS WILL KEEP HIGHEST
SUSTAINED WINDS IN THE 20-25 MPH RANGE...AND GUSTS GENERALLY 30-35
MPH WITH A FEW 40 MPH.
NO HEADLINES AS SNOW AMOUNTS AND WINDS DO NOT SUPPORT EITHER AN
ADVISORY FOR SNOW OR WINDS ALONE...THOUGH A CASE COULD BE MADE FOR A
WINTER WEATHER ADVISORY FOR THE SNOW/WIND COMBINATION. GIVEN THAT
THE MAIN PERIOD OF ACCUMULATING SNOW WILL OCCUR DURING THE MIDDAY
HOURS AND NOT DURING EITHER THE MORNING OR EVENING RUSH HOURS...AND
WINDS WILL BE DECREASING AS SNOW MOVES IN...WILL CONTINUE TO
HIGHLIGHT THE TRICKY TRAVEL CONDITIONS WITH FREQUENT SPS ISSUANCES.
.TONIGHT...FORECAST CONFIDENCE IS HIGH.
SNOW EXPECTED TO PUSH EAST OF FORECAST AREA BY 00Z WITH TEMPS
DROPPING BEHIND COLD FRONT. 925 MB TEMPS FALL TO THE TEENS BELOW
ZERO BY 12Z FRIDAY...SUPPORTING LOWS IN THE SINGLE DIGITS ABOVE IN
THE SOUTHEAST HALF OF THE CWA AND ZERO TO THE SINGLE DIGITS BELOW IN
THE NORTHWEST HALF. WIND CHILLS FRIDAY MORNING WILL BE BETWEEN -5
AND -15.
.SHORT TERM...FRIDAY THROUGH SATURDAY NIGHT...FORECAST CONFIDENCE
IS HIGH.
SHORT TERM MODELS SHOW HIGH PRESSURE SLIDING EAST ACROSS THE
REGION ON FRIDAY. ECMWF/CANADIAN MODELS TRY TO NUDGE LIGHT QPF
INTO THE FAR SOUTHERN COUNTIES BY 00Z SATURDAY...WITH THE GFS JUST
SOUTH OF THE BORDER AND NAM FURTHER SOUTH INTO NORTHERN ILLINOIS.
THIS IS IN RESPONSE TO 500 MB VORTICITY MAXIMUM SLIDING INTO THE
AREA DURING THE AFTERNOON.
MID LEVELS ARE MOIST...BUT LOW LEVELS ARE DRY. KEPT LOW POPS IN
THE FAR SOUTH AND SOUTHEAST FRIDAY AFTERNOON PER COORDINATION WITH
NEIGHBORING OFFICES...THOUGH THIS COULD END UP BEING A DRY PERIOD.
COOL HIGHS IN THE TEENS ARE EXPECTED.
SHORT TERM MODELS THEN IN GENERAL AGREEMENT WITH BRINGING SURFACE
LOW NORTHEAST ACROSS MISSOURI FRIDAY NIGHT...THEN TO THE NORTHERN
OHIO AREA SATURDAY. MODELS BRING A 500 MB VORTICITY MAXIMUM
THROUGH THE REGION SATURDAY...ALONG WITH DECENT Q VECTOR
CONVERGENCE AND FRONTOGENESIS RESPONSE IN THE MID LEVELS. CANADIAN
IS TOO AGGRESSIVE FRIDAY NIGHT WITH QPF...AND FAVORED A SOMEWHAT
SLOWER BLEND OF GFS/ECMWF.
MODELS ALL BRING A SWATH OF LIGHT TO MODERATE QPF ACROSS MOST OF
THE AREA SATURDAY MORNING...LINGERING INTO THE AFTERNOON. NAM/GFS
FORECAST SOUNDINGS SHOWING SATURATION IN DEEP LAYER WITH DENDRITE
SNOW GROWTH ZONE BEING TAPPED. BROUGHT IN HIGH POPS INTO THE FAR
SOUTHEAST SATURDAY MORNING...WITH LIKELY IN THE SOUTHEAST HALF OF
THE AREA. KEPT SIMILAR POPS SATURDAY AFTERNOON. AMOUNTS OF 1 TO 2
INCHES NORTHWEST TO 3 TO 4 INCHES SOUTHEAST ARE ANTICIPATED AT
THIS TIME.
MAY SEE MORE SNOW IN THE SOUTHEAST IF MODELS TREND MORE TO THE
NORTH...AND A WINTER WEATHER ADVISORY MAY BE NEEDED FOR LATER
FRIDAY NIGHT INTO SATURDAY IN LATER FORECASTS. WILL CONTINUE TO
MENTION IN HAZARDOUS WEATHER OUTLOOK FOR NOW. COLD AIR ADVECTION
BRINGS DRIER AIR AND QUIET WEATHER INTO THE AREA SATURDAY
NIGHT...AS WELL AS COLDER TEMPERATURES.
.LONG TERM...SUNDAY THROUGH WEDNESDAY...FORECAST CONFIDENCE IS
MEDIUM.
GFS/ECMWF AGREE ON SHOWING HIGH PRESSURE SLIDING EAST SOUTHEAST
ACROSS THE REGION SUNDAY INTO MONDAY. THIS SHOULD BRING QUIET
WEATHER TO THE AREA...ALONG WITH CONTINUED COLD TEMPERATURES.
MODELS THEN BRING A SURFACE LOW FROM THE FAR SOUTHERN PLAINS
ACROSS THE MID MISSISSIPPI RIVER VALLEY MONDAY NIGHT INTO
TUESDAY...THEN NORTHEASTWARD TUESDAY NIGHT INTO WEDNESDAY. GFS
BRINGS A SWATH OF QPF ACROSS THE AREA LATE MONDAY NIGHT INTO
TUESDAY EVENING...WITH THE ECMWF HOLDING OFF UNTIL TUESDAY
AFTERNOON AND NIGHT...ASSOCIATED WITH 500 MB VORTICITY MAXIMUM
AND MID LEVEL FRONTOGENESIS RESPONSE. THESE FEATURES REMAIN TO
THE SOUTH OF THE AREA...SO THERE IS SOME UNCERTAINTY WITH THE
EXACT PLACEMENT OF QPF THIS FAR OUT.
FOR NOW...KEPT CONSENSUS BLEND OF POPS GOING FOR MONDAY NIGHT
INTO WEDNESDAY. POPS MAY NEED TO BE RAISED LATER ON IF BETTER
MODEL AGREEMENT IS REACHED ON THIS SYSTEM. SEVERAL INCHES OF SNOW
IS POSSIBLE. COOL TEMPERATURES LINGER AS WELL.
AVIATION/12Z TAFS/...
LOOK FOR LOW-LEVEL WIND SHEAR TO CONTINUE WITH NEAR 40KT SPEED
DIFFERENTIAL FROM THE SURFACE UP TO 12K TO 14K FEET UNTIL AROUND
15Z AT KMSN...AND BETWEEN 17Z AND 18Z AT EASTERN TAF SITES. THE GUSTY
SOUTHWEST WINDS WILL CAUSE SOME DRIFTING OF THE CURRENT LIGHT
SNOW COVER OVER RUNWAYS THIS MORNING. THE WINDS WILL EASE A BIT
WITH THE APPROACH OF THE SURFACE TROUGH/COLD FRONT TRAILING FROM
LOW PRESSURE CROSSING CENTRAL WISCONSIN.
VFR CONDITIONS WILL RAPIDLY DETERIORATE WITH ACCUMULATING SNOW
AHEAD AND ALONG THE FRONT...WITH THE SNOW REACHING KMSN BETWEEN
16Z AND 17Z...KUES BETWEEN 17Z AND 18Z...AND KMKE AND KENW IN THE
18Z TO 19Z TIME FRAME. CIGS AND VSBYS WILL DIP TO MVFR LEVELS WITH
THE ONSET OF THE SNOW...DROPPING WITHIN AN HOUR OT TWO TO IFR WITH
OCCASIONAL LIFR VSBYS FOR A FEW HOURS...THEN BACK UP TO MVFR CIGS
AND VFR VSBYS AS THE SNOW ENDS WITH THE PASSAGE OF THE FRONT MID
TO LATE AFTERNOON. WEST TO NORTHWEST WINDS BEHIND THE FRONT WILL
NOT BE AS STRONG AS THE LOW WILL BE WEAKENING AS IT LIFTS
NORTHEAST OUT OF THE STATE. THE MVFR CIGS ARE EXPECTED TO SCATTER
OUT MID-EVENING...WITH VFR CONDITIONS EXPECTED FOR THE REMAINDER
OF THE FORECAST PERIOD.
MARINE...SATELLITE IMAGERY FROM POLAR ORBITER YESTERDAY AFTERNOON
SHOWED WEST WINDS HAD SHIFTED BROKEN ICE SHIELD OUT AT LEAST 10
MILES FROM SHORE. STILL NOT MUCH OPEN WATER TO BUILD WAVES...BUT
HEIGHTS CERTAINLY NOT ZERO. BRISK SOUTHWEST WINDS ARE EXPECTED TO BE
BORDERLINE GALE...BUT WITH OFFSHORE FLOW AND MINIMAL OPEN WATER FOR
MIXING UP TO STRONGER WINDS...WILL KEEP CURRENT SMALL CRAFT ADVISORY
GOING AND MENTION A FEW GALE GUSTS...WITH THE BEST POTENTIAL FROM
THIS MORNING THROUGH EARLY AFTERNOON. WINDS EASE AS SURFACE
TROUGH/COLD FRONT MOVE THROUGH THEN FREQUENT WEST WIND GUSTS TO 25
KTS FOR A BRIEF TIME EARLY THIS EVENING BEHIND FRONT. CURRENT END
TIME LOOKS GOOD.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 9 PM CST THIS EVENING FOR LMZ643>646.
&&
$$
TODAY/TONIGHT AND AVIATION/MARINE...REM
FRIDAY THROUGH WEDNESDAY...WOOD
AREA FORECAST DISCUSSION...UPDATED
NWS RENO NV
947 AM PST THU JAN 30 2014
.UPDATE...
EXTENDED THE SNOW ADVISORY FOR THE CARSON CITY AND SIERRA FRONT
FOOTHILLS UNTIL NOON AND ADDED SOUTHERN LYON AND MINERAL COUNTIES
TO THE ADVISORY TODAY.
SNOW LEVELS HAVE FALLEN TO MOST VALLEY FLOORS AS OF MID MORNING AS
THE FRONT CONTINUES TO PUSH SOUTHWARD INTO SOUTHERN NEVADA. FORCING
CONTINUES ON THE COLD SIDE OF THIS FRONT IN THE FORM OF SLOWLY
WANING FRONTOGENESIS AND UPPER JET DYNAMICS. THE HEAVIER BAND OF
SNOW HAS BEEN SLOW TO WEAKEN BUT SHOULD DO SO AS WE HEAD INTO
EARLY AFTERNOON AS FORCING EXITS. THE HEAVIEST SNOWFALL THROUGH
EARLY AFTERNOON WILL BE NEAR AND JUST SOUTH OF HIGHWAY 50 WHERE
TOTAL SNOW ACCUMULATIONS WILL EXCEED A FOOT ABOVE 5000 FEET WITH A
WET HALF A FOOT ON SOME VALLEY FLOORS DOWN TO 4500 FOOT. A SUMMARY
STORM REPORT WILL BE ISSUED BY 11 AM.
OUR ATTENTION FOR THE AFTERNOON PACKAGE WILL BE SHORTWAVE TONIGHT
WHICH THE GFS/NAM ARE HANDLING SIMILARLY NOW. WILL BE ADJUSTING
POPS AND SNOW AMOUNTS AND CONSIDERING ADDITIONAL ADVISORIES AS
SEVERAL INCHES OF SNOW WILL BE POSSIBLE, BOTH IN THE SIERRA AND
WESTERN NV. THIS SECOND SYSTEM WILL HAVE A MUCH COLDER AIRMASS TO
WORK WITH AND THUS HAS POTENTIAL TO IMPACT MANY AREAS. MORE THIS
AFTERNOON. HOHMANN
&&
.PREVIOUS DISCUSSION... /ISSUED 642 AM PST THU JAN 30 2014/
UPDATE...
WILL BE DROPPING THE WINTER WEATHER ADVISORY FOR CAZ071 (SIERRA
NORTH OF I-80). BASED ON RADAR TRENDS AND MODEL GUIDANCE THREAT
FOR SUBSTANTIAL ADDITIONAL ACCUMULATIONS APPEARS MINIMAL FOR THAT
AREA. A FEW LIGHT SNOW SHOWERS ARE CERTAINLY POSSIBLE THOUGH.
SNOW HAS BEEN PERSISTENT IN THE CARSON VALLEY THIS MORNING
ASSOCIATED WITH LOCALLY LOWER SNOW LEVELS AND BETTER FORCING FOR
ASCENT ALONG COLD FRONT. JUST RECEIVED A SPOTTER REPORT OF 2.5
INCHES IN CARSON CITY. WILL BE UPDATING THE NVZ003 ADVISORY AND
FORECAST TO INCREASE SNOW AMOUNTS IN THAT AREA INTO 1-3 INCH RANGE
FOR THIS MORNING.
NEW GUIDANCE CONTINUES TO ADVERTISE A SECONDARY AREA OF SNOW
TONIGHT ASSOCIATED WITH UPPER SHORTWAVE. LATEST HRRR IS SHOWING
SNOW SHOWERS DEVELOPING QUICKLY AFTER 0Z OVER THE SIERRA AND THEN
PRESSING EASTWARD. THEREFORE HAVE INCREASED POPS AND SNOW
POTENTIAL FOR THE SIERRA AND WESTERN NEVADA INCLUDING RENO/CARSON
CITY FOR TONIGHT. A COUPLE INCHES POSSIBLE DOWN TO THE VALLEY
FLOORS GIVEN LOWER SNOW LEVELS. ANY ACCUMULATIONS WILL RESULT IN
SLICK ROADS GIVEN THE COLDER TEMPERATURES. WE MAY END UP NEEDING
ANOTHER ADVISORY FOR THIS, BUT WILL LET THE DAY SHIFT TAKE A FRESH
LOOK AT THE 12Z GUIDANCE BEFORE DECIDING.
UPDATED FORECAST AND ADVISORIES OUT SHORTLY.
CS
PREVIOUS DISCUSSION... /ISSUED 327 AM PST THU JAN 30 2014/
SYNOPSIS...
A LOW PRESSURE SYSTEM WILL BRING MOUNTAIN SNOW AND LOWER
ELEVATION RAIN AND SNOW TODAY WITH THE THREAT FOR SNOW SHOWERS
LINGERING THROUGH FRIDAY. HIGH PRESSURE WILL BUILD OVERHEAD FOR
THE WEEKEND WITH DRY CONDITIONS AND BELOW AVERAGE AFTERNOON
TEMPERATURES THROUGH EARLY NEXT WEEK.
SHORT TERM...
GOOD UPPER LEVEL FORCING CONTINUES AHEAD OF THE UPPER LOW APPROACHING
THE CALIFORNIA COAST AS EVIDENCED BY COOLING CLOUD TOPS IN THE
INFRARED SATELLITE. AT THE LOWER LEVELS, A COLD FRONT HAS PUSHED
SOUTH INTO MONO AND MINERAL COUNTIES WITH MOIST FLOW ATOP THE SURFACE
AIRMASS BRINGING A LARGE SWATH OF RAIN AND SNOW TO THE REGION.
MODELS HAVE SHOWN NOTABLE FRONTOGENESIS CENTERED AROUND 12Z/4 AM IN
WESTERN NEVADA FROM ABOUT RENO NORTH FOR A FEW RUNS. BASED ON
PRECIPITATION PLACEMENT (PER RADAR) AND SATELLITE IMAGERY, THE
MODELS MAY HAVE BEEN JUST A BIT TOO FAR NORTH WITH THE BEST FORCING.
BASED ON UPSTREAM ACTIVITY AND THE LATEST 3-KM HRRR, THE HEAVIEST
PRECIPITATION THIS MORNING WILL BE NEAR AND SOUTH OF HIGHWAY 50.
FOR AREAS THAT DO NOT RECEIVE HEAVIER PRECIPITATION IN AREAS BELOW
ABOUT 5500 FEET, LITTLE SNOW IS LIKELY TO ACCUMULATE WITH TEMPERATURES
RUNNING IN THE LOW TO MID 30S (AND NO COLDER OR DRIER AIR TO ADVECT
IN FROM THE NORTH).
STILL, FOR WESTERN NEVADA I WILL LEAVE THE SNOW ADVISORY ABOVE
5000 FEET GOING FOR NOW AS AREAS SOUTH OF RENO IN THE FOOTHILLS
COULD CERTAINLY SEE A FEW INCHES OF SNOWFALL THIS MORNING. AS FAR
AS THE SIERRA, THE FORECAST SEEMS ON TRACK WITH AT LEAST A FEW
MORE HOURS OF MODERATE TO OCCASIONALLY HEAVY SNOWFALL IN THE TAHOE
AREA AND HEAVIER PRECIPITATION WORKING SOUTH TO THE MAMMOTH AREA
THIS MORNING. RESIDUAL SHOWERS WILL CONTINUE INTO THE AFTERNOON
ESPECIALLY SOUTH OF HIGHWAY 50 AND IN THE SIERRA ALTHOUGH WITH
ACTIVITY TAPERING OFF AND DAYTIME ROAD HEATING ACCUMULATIONS
SHOULD REMAIN MODEST.
MOVING ON TO THE SECOND ROUND OF POSSIBLE SNOWFALL FOR TONIGHT,
THE NAM AND GFS CONTINUE TO WIDESPREAD SNOW SHOWERS BREAKING OUT
THIS EVENING AND CONTINUING OVERNIGHT. THE ECMWF ALSO HAS SOME
SHOWER ACTIVITY ALTHOUGH IT IS RESTRICTED TO NEAR THE SIERRA.
SNOW RATIOS WILL BE HIGHER AS THE AIRMASS WILL BE COLDER BY THIS
EVENING SO IT WILL NOT TAKE AS MUCH PRECIPITATION TO CREATE SOME
SNOWFALL. STILL, I AM NOT EXPECTING TOO MUCH SNOWFALL AS THERE IS
NO LOW LEVEL FORCING EVIDENT TO AID UPPER FORCING WITH THE
DISTURBANCE SO SNOW SHOULD REMAIN ON THE LIGHT SIDE.
SNOW SHOWERS TAPER OFF ON FRIDAY AS THE UPPER DISTURBANCE MOVES
OFF INTO CENTRAL AND EASTERN NEVADA. STILL, COLD CYCLONIC FLOW
WILL PERSIST SO A FEW LIGHT SNOW SHOWERS CANNOT BE RULED OUT. IT
WILL BE CHILLY WITH BELOW AVERAGE HIGHS AS 700 MB TEMPERATURES
REMAIN AROUND -10C TO -12C. SNYDER
LONG TERM...SATURDAY THROUGH WEDNESDAY...
GLOBAL MODELS ARE IN REASONABLE AGREEMENT ON THE LARGE SCALE PATTERN
FOR THE EXTENDED, BOTH SHOWING A DEVELOPING RIDGE AROUND 135W WITH
COOL, DRY NW FLOW OVER THE CA/NV REGION. THERE ARE SOME SIGNS OF THE
RIDGE FLATTENING PAST FEB 6, WHICH SHOWS UP IN THE ESRL ANALOGS AS AN
INCREASED CHANCE OF SEEING ANOTHER PACIFIC STORM IN THE D8-14 PERIOD.
PRIMARY ISSUE TO CONTEND WITH IS THE UPPER LOW FORECAST TO DROP SE
ALONG THE CA COASTLINE SUNDAY. GUIDANCE HAS GENERALLY SHOWN PRECIP
ASSOCIATED WITH THIS FEATURE REMAINING WEST OF THE SIERRA, BUT THERE
ARE ABOVE NORMAL SPREADS IN THE GEFS/EC ENSEMBLES SUGGESTING AMPLE
UNCERTAINTY IN THE TRACK/AMPLITUDE OF THE SYSTEM. LATEST EC
SOLUTION IS FURTHER EAST AND BRINGS SHOWERS TO THE CENTRAL/SOUTHERN
SIERRA - SO HAVE INCREASED CHANCES OF SNOW SHOWERS FOR MONO CO
SUNDAY INTO SUNDAY NIGHT. SHOULD THE SYSTEM TRACK FURTHER EAST, THEN
WE COULD BE LOOKING AT ACCUMULATING SNOWS SOUTH OF BRIDGEPORT.
TEMPERATURES SAT/SUN WILL BE QUITE CHILLY GIVEN NE LOW LEVEL FLOW
AND 700MB TEMPS DIPPING TO -12C OR SO. EVEN WITH SUNSHINE, GUIDANCE
HAS TRENDED COOLER FOR SAT/SUN, AND HAVE ADJUSTED THE FORECAST
ACCORDINGLY. WITH CLEAR SKIES ANTICIPATED, SUN MORNING LOWS WILL BE
THE COLDEST WITH WIDESPREAD TEENS IN WRN NV VALLEYS, AND BELOW ZERO
IN THE COLDER SIERRA VALLEYS (WITH SNOWCOVER). REST OF THE EXTENDED
APPEARS LARGELY DRY, ALTHOUGH GUIDANCE SHOWS VARIOUS SMALL SCALE
WAVES EMBEDDED WITHIN THE NW FLOW ALOFT. THESE COULD GENERATE SOME
LIGHT SHOWERS BUT PREDICTABILITY IS LOW - SO I`M MAINTAINING A DRY
FORECAST MON-WED. TEMPERATURES WILL SHOW A SLOW MODERATING TREND. CS
AVIATION...
ONGOING WINTER STORM WILL CONTINUE TO IMPACT THE REGION THROUGH
TODAY. FOLLOWED HRRR GUIDANCE FOR THE MOST PART AS IT`S CAPTURING
CURRENT TRENDS REASONABLY WELL. A SECOND BURST OF SNOW IS POSSIBLE
TONIGHT AND EARLY FRIDAY MORNING WITH A PASSING SHORTWAVE ALOFT
BUT FORECAST CONFIDENCE IN THAT IS LOWER. HERE`S THE DETAILS -
FOR RNO/CXP - PERIODS OF RAIN THROUGH 18Z/TODAY WITH A MIX OF MVFR
AND IFR CONDITIONS. RAIN MAY MIX WITH SNOW AT TIMES AS SNOW LEVELS
FALL TO NEAR 4500-4800 FEET. SNOW ACCUMULATIONS ARE UNLIKELY AT RNO,
BUT NOT ENTIRELY OUT OF THE QUESTION FOR CXP IF WE SEE A
PARTICULARLY HEAVY BURST OF PRECIPITATION BETWEEN 11-15Z. AFTER
18Z, THE BAND OF RAIN/SNOW SINKS SOUTHWARD AND SHOULD PROVIDE A
BREAK THROUGH 03Z/FRIDAY WITH ONLY ISOLATED LIGHT SHOWERS
POSSIBLE. AFTER 03Z/FRIDAY, A SECOND AREA OF SNOW SHOWERS IS
POSSIBLE THROUGH ABOUT 9-12Z/FRIDAY. SNOW LEVELS WOULD BE LOWER,
AND IF THIS SNOW PANS OUT IT WOULD LIKELY ACCUMULATE ON UNTREATED
SURFACES. FORECAST CONFIDENCE IS ADMITTEDLY ONLY LOW TO MEDIUM
RIGHT NOW AS THERE IS STILL VARIABILITY IN MODEL GUIDANCE. BUT
SOMETHING TO WATCH AS IT COULD IMPACT LATE NIGHT OR EARLY MORNING
FLIGHT OPERATIONS.
FOR TVL/TRK - SNOW LEVELS HAVE BEEN SLOW TO FALL AT TVL, REMAINING
RAIN AS OF 9Z. THIS SHOULD CHANGE TO SNOW WITHIN THE NEXT FEW HOURS
AS COLDER AIR MOVES IN. WITHIN GENERAL AREA OF ONGOING RAIN/SNOW,
HRRR GUIDANCE BRINGS IN A BURST OF HEAVY SNOW BETWEEN 11-15Z. THIS
WILL RESULT IN IFR/LIFR CONDITIONS WITH SEVERAL INCHES SNOW
ACCUMULATION. PRECIP INTENSITY SHOULD LIGHTEN UP AFTER 18Z WITH
SCT SNOW SHOWERS REMAINING POSSIBLE THROUGH TODAY. ANOTHER ROUND
OF SNOW IS POSSIBLE BETWEEN ABOUT 00Z-09Z/FRIDAY BUT FORECAST
CONFIDENCE IS LOW TO MEDIUM DUE TO VARIABILITY IN MODEL GUIDANCE.
SHOULD THIS NEXT ROUND OF SNOW PAN OUT, THEN PERIODS OF IFR/LIFR
ARE LIKELY.
FOR MMH - STRONG WESTERLY WINDS ARE ONGOING AS THE AIRFIELD REMAINS
SHADOWED FROM PRECIPITATION. NAM PICKED UP ON THIS WELL AND THESE
WINDS SHOULD START TO SUBSIDE AS RAIN/SNOW MOVES INTO THE AREA AFTER
12Z. PERIODS OF MVFR/IFR CONDITIONS IN SNOW ARE LIKELY BETWEEN 12Z
AND 00Z/FRIDAY WITH MEDIUM TO HIGH FORECAST CONFIDENCE. SNOW
ACCUMULATIONS ARE LIKELY ESPECIALLY AFTER 18Z AS TEMPERATURES DROP.
ANOTHER ROUND OF LIGHT SNOW AND MVFR/IFR CONDITIONS IS POSSIBLE FROM
ROUGHLY 6Z-18Z/FRIDAY BUT FORECAST CONFIDENCE IS LOW DUE TO
VARIABILITY IN MODEL GUIDANCE. CS
&&
.REV WATCHES/WARNINGS/ADVISORIES...
NV...WINTER STORM WARNING UNTIL 4 AM PST FRIDAY NVZ002.
WINTER WEATHER ADVISORY UNTIL 4 PM PST THIS AFTERNOON ABOVE 4500
FEET FOR NVZ001.
WINTER WEATHER ADVISORY UNTIL NOON PST TODAY ABOVE 5000 FEET FOR
NVZ003.
CA...WINTER WEATHER ADVISORY UNTIL 4 AM PST FRIDAY ABOVE 7000 FEET
FOR CAZ073.
WINTER STORM WARNING UNTIL 4 AM PST FRIDAY CAZ072.
&&
$$
FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
403 PM EST THU JAN 30 2014
.SYNOPSIS...
HIGH PRESSURE SETTLES OVER THE REGION TODAY THROUGH SATURDAY. A
COLD FRONT APPROACHES THE REGION SATURDAY NIGHT AND IS EXPECTED
TO CROSS THE AREA ON SUNDAY.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
A STALLED FRONTAL BOUNDARY (EXTENDING FROM WELL OFF THE SE COAST
TO SRN FLORIDA) AND SOUTHWEST STEERING FLOW ALOFT WILL KEEP A
STEADY STREAM OF LOW STRATUS ACROSS NE NC EARLY THIS EVENING...
WHICH IS THEN EXPECTED TO SPREAD NWD INTO FAR SE VA OVERNIGHT. THE
CLOUD COVER SHOULD INSULATE THE ATMOSPHERE AND KEEP TEMPERATURES
FROM BOTTOMING OUT IN THE SINGLE DIGITS ABOVE/BELOW ZERO LIKE
EARLY THIS MORNING IN THOSE AREAS. EXPECT LOWS IN THE 20S HERE.
MODELS CONTINUE TO GENERATE VERY LIGHT PRECIP UNDER THIS CLOUD
SHIELD BUT AM ONLY ANTICIPATING LOW STRATUS TO PERSIST THROUGH THE
NIGHT. IF ANY PRECIP DOES OCCUR...IT SHOULD BE LIGHT SNOW
FLURRIES. THE REST OF THE AREA WILL BE MOSTLY CLEAR OVERNIGHT WITH
LOWS RANGING FROM 15-20 DEGREES. PATCHY FREEZING FOG WAS OBSERVED
EARLIER THIS MORNING DUE TO SUBLIMATION OF SNOW ON THE GROUND.
PATCHY FREEZING FOG WILL BE POSSIBLE AGAIN TONIGHT AS SHALLOW SFC
INVERSIONS DEVELOP...BUT DO NOT EXPECT VISIBILITY OR TRAVEL
IMPACTS FROM IT.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY/...
HIGH PRESSURE REMAINS OVER THE AREA ON FRIDAY/FRIDAY NIGHT.
SHALLOW SFC INVERSIONS SHOULD BREAK SHORTLY AFTER SUNRISE AND
TEMPS SHOULD HAVE NO PROBLEM WARMING TWD VALUES THAT ARE SLIGHTLY
BELOW NORMAL FOR THE END OF JANUARY. HIGHS WILL GENERALLY BE IN
THE MID 40S. LOWS FRIDAY NIGHT WILL STAY ON THE COLD SIDE UNDER
MOSTLY CLEAR TO PARTLY CLOUDY SKIES (MAINLY HIGH CLOUDS) WITH
REMNANT SNOWPACK IN THE AREA. EXPECT LOW TEMPS IN THE MID 20S
(NEAR 30 AT THE IMMEDIATE COAST).
HIGH PRESSURE SLIDES OFFSHORE ON SATURDAY AS A LOW PRESSURE SYSTEM
TRACKS NE THROUGH THE OHIO VALLEY. THE AREA FALLS WITHIN A SPLIT
FLOW PATTERN AS MOISTURE STAYS CONFINED TO THE OHIO VALLEY LOW AS
WELL AS IN THE VICINITY OF THE SE COAST. THE MOISTURE MOVING INTO
THE SE STATES IS ATLANTIC MOISTURE BEING PULLED AROUND THE
PERIPHERY OF THE DEPARTING HIGH. THE MID ATLANTIC REGION SHOULD
EXPERIENCE INCREASING CLOUDS THROUGH THE DAY BUT NO PRECIPITATION
IS EXPECTED. WARM AIR ADVECTION PROCESSES WILL BE WELL UNDER WAY...
ESPECIALLY AS S-SW WINDS BECOME BREEZY SATURDAY AFTN. HIGH TEMPS
ARE EXPECTED TO WARM TO READINGS AROUND 5-7 DEGREES ABOVE NORMAL
AND COULD TREND UPWARD IF THE WINDS INCREASE IN CONSECUTIVE MODEL
RUNS. THE OHIO VALLEY LOW TRACKS INTO THE ERN ST LAWRENCE RIVER
VALLEY SATURDAY NIGHT AND ITS ASSOCIATED COLD FRONT WILL APPROACH
THE REGION OVERNIGHT WITH BALMY LOWS IN THE UPPER 30S NW TO
MID-UPPER 40S FAR SE BY SUNDAY MORNING. THE COMBINATION OF
INCREASING MOISTURE IN THIS PATTERN AND RECENT SNOWMELT WILL
SATURATE THE LOWER ATMOSPHERE. AS SFC INVERSIONS DEVELOP SATURDAY
NIGHT...FOG IS EXPECTED TO DEVELOP OVERNIGHT AND PERSIST INTO MID
MORNING SUNDAY. THE FRONT CROSSES THE AREA SUNDAY AFTN...BRINGING
A QUICK SHOT OF LIGHT RAIN. TEMPS SHOULD PEAK IN THE MID 50S NW
AND IN THE LOW-MID 60S SE.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
A MORE ZONAL PATTERN ACRS THE CONUS RESULTS IN RELAXATION OF THE
VERY COLD CONDS THROUGH LT NEXT WK...BUT ALSO INTRODUCES PTNTL
INCRSG STORMINESS AND FORECAST CHALLENGES. WHILE A RETURN TO
EXTREMELY COLD CONDS NOT XPCD THROUGH BALANCE OF NEXT WK...PLENTY
OF COLD AIR WILL RMN IN SRN CANADA...WHICH MAY ADD TO ANY STM/PCPN
CHALLENGES.
AS SFC CDFNT SETTLES S OF THE RGN SUN NGT INTO MON...WK WAVE OF LO
PRES TRACKING ALG IT BRINGS CLDS AND CHC PCPN (PSBL LGT MIX ACRS
FAR NRN COUNTIES...OTRW RA). DRYING OUT MON NGT INTO TUE. ANOTHER
ROUND OF MOISTURE RETURNS DURING TUE AS NEXT/COMPLEX STM SYS
EJECTS FM THE SRN PLAINS THROUGH THE LWR MS VLY (TUE)...THEN CONTG
TO TRACK TO THE NE WED. MDLS CONTG TO SUGGEST LO LVL CAD AHD OF
THAT SYS (PREVENTING ANY QUICK WARMING). SCOURING OUT THE LO LVL
CAD ON WED MAY BE PROBLEMATIC FAR INLAND (TEMPS IN THE
40S)...WHILE WARMING OCCURS ELSW (TO THE 50S/60S). ALSO...WILL
CONT W/ CHC POPS (RA) AHD OF...AND W/ PASSAGE OF CDFNT (ON WED).
COLDER (SEASONABLE)/DRIER WX XPCD THU.
&&
.AVIATION /20Z THURSDAY THROUGH TUESDAY/...
LIGHT NORTHEAST TO EAST WINDS WILL PREVAIL AT THE TAF SITES THROUGH
THURSDAY EVENING. THE NAM AND RUC BOTH INDICATE THAT THE ONSHORE
FLOW WILL BRING AN INCREASE OF LOW LEVEL MOISTURE STARTING OVER
NORTHEAST NORTH CAROLINA THIS EVENING AND SPREADING INTO SOUTHEAST
VIRGINIA OVERNIGHT. INCLUDED MVFR CIGS AT ORF AND ECG FOR A FEW
HOURS NEAR SUNRISE...HOWEVER IFR CANNOT BE RULED OUT BUT IS NOT
EXPECTED. FREEZING FOG MAY DEVELOP AGAIN OVERNIGHT BUT THE IMPACTS
IN THE LOWER ATMOSPHERE SHOULD RESULT IN MORE OF A HAZE THAN TRUE
FOG. OTHERWISE...VFR CONDS AND LIGHT WINDS ARE EXPECTED THROUGH
FRIDAY.
OUTLOOK...A WARM FRONT WILL LIFT ACROSS THE REGION SATURDAY...BEFORE
ANOTHER COLD FRONT CROSSES THE REGION SUNDAY. THERE IS A CHANCE OF
PCPN SUN INTO EARLY NEXT WEEK.
&&
.MARINE...
A SURFACE HIGH PRESSURE RIDGE WILL REMAIN OVER THE MID ATLANTIC
COAST THROUGH FRIDAY AND THEN SLOWLY SLIDE TO THE SOUTH. VARIABLE
WINDS WILL BECOME S/SW LATE FRIDAY AND SATURDAY BUT SHOULD REMAIN
BELOW SCA. THE SW WINDS WILL CONTINUE AHEAD OF A COLD FRONT WHICH
IS FORECAST TO MOVE ACROSS THE WATERS SUNDAY EVENING. WINDS SHIFT
TO NORTHERLY BEHIND THE FRONT. A NORTH TO NORTHEAST FETCH MAY
PRODUCE SEAS OF 5 FT MONDAY AND TUESDAY...MAINLY IN THE SOUTHERN
COASTAL WATERS. OTHERWISE...THE PRESSURE GRADIENT APPEARS TOO WEAK
FOR SCA CONDITIONS. BOTH THE EURO AND GFS INDICATE A STRONGER
SYSTEM WILL MOVE THROUGH THE AREA AROUND MID WEEK WHICH WILL
LIKELY BE ASSOCIATED WITH SCA CONDITIONS.
&&
.CLIMATE...
* NORFOLK HAS BROKEN A RECORD LOW THIS MORNING WITH A TEMPERATURE
OF 6 F. THE PREVIOUS RECORD WAS 10 F IN 1934. THIS IS THE
COLDEST READING SINCE IT WAS 5 DEG ON JAN 19, 1994.
* ELIZABETH CITY HAS BROKEN A RECORD LOW THIS MORNING WITH A
TEMPERATURE OF 7 F. THE PREVIOUS RECORD WAS 9 F IN 1934.
* SALISBURY HAS BROKEN A RECORD LOW THIS MORNING WITH A
TEMPERATURE OF -6 F. THE PREVIOUS RECORD WAS IN 1940.
* WALLOPS ISLAND HAS BROKEN A RECORD LOW THIS MORNING WITH A
TEMPERATURE OF 3 F. THE PREVIOUS RECORD WAS 13 F IN 1986.
* RICHMOND HAD A LOW TEMPERATURE OF 4 F THIS MORNING. THE RECORD
LOW FOR TODAY IS -3 F FROM 1940.
* WFO WAKEFIELD DROPPED TO -5 F THIS MORNING. THIS IS ONLY THE
THIRD TIME THAT AKQ HAS BEEN BELOW ZERO SINCE THE OFFICE OPENED
(NEARLY 20 YEARS). OTHER BELOW ZERO READINGS WERE -5 F ON
JAN 28, 2000...AND -4 F ON FEB 05, 1996.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...BMD
NEAR TERM...BMD
SHORT TERM...BMD
LONG TERM...ALB
AVIATION...LSA
MARINE...LSA
CLIMATE...AKQ
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
147 PM EST THU JAN 30 2014
.SYNOPSIS...
HIGH PRESSURE SETTLES OVER THE REGION TODAY THROUGH SATURDAY. A
COLD FRONT APPROACHES THE REGION SATURDAY NIGHT AND IS EXPECTED
TO CROSS THE AREA ON SUNDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
UPDATE...
HIGH PRESSURE WILL BE STRETCHED ALONG THE LEESIDE OF THE
APPALACHIANS FROM THE NE TO SE STATES TODAY. EXCELLENT RADIATIONAL
COOLING CONDITIONS OVERNIGHT HAVE RESULTED IN RECORD-BREAKING LOW
TEMPERATURES EARLIER THIS MORNING. PLEASE SEE THE CLIMATE SECTION
BELOW. A PUBLIC INFORMATION STATEMENT (PNSAKQ) HAS ALSO BEEN
ISSUED AND CONTAINS ADDITIONAL LOW TEMPERATURE INFORMATION FOR
THIS MORNING. WILL ISSUE ANOTHER UPDATED STATEMENT LATE THIS
MORNING SHOWING LOW TEMPERATURES ACROSS THE AREA.
SHALLOW SFC INVERSIONS HAVE ALREADY BROKEN AND TEMPERATURES ARE
ALREADY CLIMBING NICELY. HAD CONSIDERED LOWERING HIGH TEMPS FOR
THIS AFTN BUT WILL KEEP THE CURRENT FORECAST INTACT WITH HIGHS IN
THE LOW-MID 30S. THIS IS ABOUT 1.0-1.5 STD DEV BELOW NORMAL FOR
THE END OF JANUARY. PLENTY OF SUNSHINE WILL HELP MELT ICY AND
SNOWPACKED SECONDARY ROADS TODAY. MEANWHILE...A STALLED FRONTAL
BOUNDARY (EXTENDING FROM WELL OFF THE SE COAST TO SRN FLORIDA) AND
SOUTHWEST STEERING FLOW ALOFT WILL KEEP A STEADY STREAM OF MID-
HIGH LEVEL STRATUS ACROSS NE NC/FAR SE VA.
PREVIOUS DISCUSSION...
00Z NAM/ECMWF AND LATEST SREF GUIDANCE INDICATE A SLIGHT CHC FOR
SOME PRECIP REACHING NE NC TONIGHT. HOWEVER...GIVEN STRENGTH OF
SFC HIGH IN PLACE AND OVERALL DRY AIRMASS...FIND IT HARD TO
BELIEVE ANY PRECIP WOULD REACH THE GROUND. WILL THEREFORE KEEP
FORECAST DRY AND SHOW AN INCREASE IN STRATUS NEAR THE COAST. CLEAR
TO PARTLY CLOUDY ELSEWHERE. NOT AS COLD WITH LOWS IN THE MID TEENS
TO MID 20S.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY/...
HIGH PRESSURE REMAINS ANCHORED OVER THE MID-ATLANTIC STATES FRIDAY
AND SATURDAY WITH DRY WX EXPECTED. THE COLD AIRMASS SHOULD FINALLY
RETREAT IN ERNEST AS UPPER LEVEL HIGH PRESSURE BUILDS OF THE SE
COAST. S-SW FLOW AT THE SFC WILL LEAD TO MODERATING TEMPS THRU
SAT. HIGHS FRIDAY IN THE 40S...THEN UPR 40S TO MID 50S SATURDAY.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
A MORE ZONAL PATTERN ACRS THE CONUS RESULTS IN RELAXATION OF THE
VERY COLD CONDS THROUGH MID NEXT WK...BUT ALSO INTRODUCES PTNTL
INCRSG STORMINESS AND FORECAST CHALLENGES. WHILE A RETURN TO
EXTREMELY COLD CONDS NOT XPCD THROUGH BALANCE OF NEXT WK...PLENTY
OF COLD AIR WILL RMN IN SRN CANADA...WHICH MAY ADD TO ANY STM/PCPN
CHALLENGES.
SFC LO PRES TRACKS FM THE LAKES THROUGH NEW ENG SAT NGT/SUN...W/
ITS TRAILING CDFNT FOLLOWING ACRS THE FA (ON SUN) BRINGING INCRSD
PCPN CHCS (RA). GRADUAL DRYING SUN NGT...THEN A QUICK MOVING SYS
IN SWLY FLO ALOFT ARRIVES MON W/ PCPN CHCS (MNLY RA). ANOTHER
ROUND OF MOISTURE RETURNS BY TUE AS NEXT/COMPLEX STM SYS EJECTS FM
THE SRN PLAINS THROUGH THE LWR MS VLY (TUE)...THEN CONTG TO TRACK
TO THE NE WED. MDLS AT THIS POINT HINTING AT LO LVL CAD AHD OF
THAT SYS (PREVENTING ANY QUICK WARMING).
&&
.AVIATION /19Z THURSDAY THROUGH TUESDAY/...
LIGHT NORTHEAST TO EAST WINDS WILL PREVAIL AT THE TAF SITES THROUGH
THURSDAY EVENING. THE NAM AND RUC BOTH INDICATE THAT THE ONSHORE
FLOW WILLL BRING AN INCREASE OF LOW LEVEL MOISTURE STARTING OVER
EASTERN NORTH CAROLINA AND SPREADING INTO SE PORTIONS. INCLUDED
MVFR CIGS AT ORF AND ECG FOR A FEW HOURS NEAR SUNRISE. IFR CANNOT
BE RULED OUT BUT IS NOT EXPECTED. OTHERWISE...VFR CONDS AND LIGHT
WINDS ARE EXPECTED THROUGH FRIDAY.
OUTLOOK...A WARM FRONT WILL LIFT ACROSS THE REGION SATURDAY...BEFORE
ANOTHER COLD FRONT CROSSES THE REGION SUNDAY. THERE IS A CHANCE OF
PCPN EARLY NEXT WEEK.
&&
.MARINE...
SURFACE HIGH PRESSURE REMAINS OVER THE MID ATLANTIC COAST THROUGH
TONIGHT...BEFORE SLOWLY DRIFTING OFFSHORE THROUGH SATURDAY. A
10-15KT NE WIND EARLY TODAY WILL RELAX BY AFTERNOON/EARLY EVENING.
AS HIGH PRESSURE MOVES OFF THE COAST...A SW WIND WILL DEVELOP AND
CONTINUE THROUGH SUNDAY MORNING. WIND SPEEDS COULD APPROACH SCA
CRITERIA LATE SATURDAY NIGHT/EARLY SUNDAY AHEAD OF THE NEXT COLD
FRONT...BUT WILL MAINTAIN SUB-SCA CONDITIONS AS CONFIDENCE IS RATHER
LOW. THIS COLD FRONT DROPS ACROSS THE REGION SUNDAY
AFTERNOON/EVENING. LOW PRESSURE DEVELOPS ALONG THE BOUNDARY AND
TRACKS SOUTH OF THE REGION LATE SUNDAY NIGHT INTO MONDAY. THIS WILL
HELP ENHANCE LOW-LEVEL NORTHERLY CAA RESULTING FROM HIGH PRESSURE
BUILDING NORTH OF THE REGION. HIGH PRESSURE REMAINS N OF THE AREA
THROUGH TUESDAY AS THE FRONTAL BOUNDARY LINGERS S OF THE REGION.
THIS WILL PRODUCE A PERIOD OF PROLONGED NE FLOW. LOW PRESSURE TRACKS
N OF THE REGION DURING THE MIDDLE OF NEXT WEEK FOLLOWED BY A COLD
FRONT.
&&
.CLIMATE...
* NORFOLK HAS BROKEN A RECORD LOW THIS MORNING WITH A TEMPERATURE
OF 6 F. THE PREVIOUS RECORD WAS 10 F IN 1934. THIS IS THE
COLDEST READING SINCE IT WAS 5 DEG ON JAN 19, 1994.
* ELIZABETH CITY HAS BROKEN A RECORD LOW THIS MORNING WITH A
TEMPERATURE OF 7 F. THE PREVIOUS RECORD WAS 9 F IN 1934.
* SALISBURY HAS BROKEN A RECORD LOW THIS MORNING WITH A
TEMPERATURE OF -6 F. THE PREVIOUS RECORD WAS IN 1940.
* WALLOPS ISLAND HAS BROKEN A RECORD LOW THIS MORNING WITH A
TEMPERATURE OF 3 F. THE PREVIOUS RECORD WAS 13 F IN 1986.
* RICHMOND HAD A LOW TEMPERATURE OF 4 F THIS MORNING. THE RECORD
LOW FOR TODAY IS -3 F FROM 1940.
* WFO WAKEFIELD DROPPED TO -5 F THIS MORNING. THIS IS ONLY THE
THIRD TIME THAT AKQ HAS BEEN BELOW ZERO SINCE THE OFFICE OPENED
(NEARLY 20 YEARS). OTHER BELOW ZERO READINGS WERE -5 F ON
JAN 28, 2000...AND -4 F ON FEB 05, 1996.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...JDM
NEAR TERM...BMD/JDM
SHORT TERM...JDM
LONG TERM...ALB
AVIATION...LSA
MARINE...AJZ
CLIMATE...
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1242 PM EST THU JAN 30 2014
.UPDATE...
ISSUED AT 1052 AM EST THU JAN 30 2014
...MUCH OF CNTRL CWA UPGRADED TO WINTER STORM WARNING THROUGH REST OF
THE DAY...
VERY HEALTHY DYNAMIC UPPER LEVEL SYSTEM IMPACTS UPR MICHIGAN THROUGH
THE AFTN...BRINGING MODERATE TO HEAVY SNOW TO MUCH OF THE CWA. WV
LOOP SHOWS INITIAL SHORTWAVE PUSHING ACROSS NORTHERN IOWA WITH COMMA
HEAD BACK OVER SOUTHERN MINNESOTA. DIFFLUENCE ALOFT IS STRONG AS
UPPER LAKES IS WITHIN COUPLED JET STRUCTURE WITH JET STREAK OVER
ONTARIO AND ANOTHER SLIDING TOWARD NORTHERN ILLINOIS. AGEOSTROPIC
RESPONSE ONLY INCREASES THROUGH THE DAY ACROSS UPR MICHIGAN HELPING
TO INCREASE THE ALREADY PRESENT DIVERGENCE ALOFT. SNOW THAT ARRIVED
QUICKER THAN EXPECTED THIS MORNING WAS MOSTLY DUE TO ISENTROPIC
ASCENT AT 285K AHEAD OF COLD FRONT NOW MOVING TO IWD-MQT CORRIDOR.
THIS ISENTROPIC LIFT HAS ALREADY PRODUCED 1-2 INCHES FROM DICKINSON
THROUGH ALGER COUNTIES PER THE 88D SNOW ALGORITHM USING A SLR OF
18:1. WV LOOP AND RADAR UPSTREAM/SFC OBS INDICATE WE STILL HAVE TO GO
THROUGH A SWATH OF HEAVY SNOW OVER CNTRL UPR MICHIGAN THIS AFTN.
RUC13/NAM12 BOTH SHOW THIS FAVORED AREA WILL BE ALONG AND NORTH OF
INITIAL SHORTWAVE MOVING ACROSS NORTHERN LK MICHIGAN AND ALSO JUST
TO THE NORTH AND EAST OF SFC LOW LIFTING INTO NORTHEAST WI. SNOW WILL
ALSO BE HELPED ALONG BY H85-H65 FRONTOGENESIS AND PERHAPS SOME
NEGATIVE EPV ATOP THAT FGEN WHICH COULD RESULT IN BANDED SNOW...FURTHER
BOOSTING SNOW TOTALS. OVERALL...EXPECT 3-5 INCHES OVER ROUGHLY THE
EAST 2/3 OF THE CWA. HOWEVER...IN THESE CNTRL CWA AREAS
HIGHLIGHTED...COULD SEE TOTALS OVER 6 INCHES FROM IRON MOUNTAIN TO
ESCANABA...NORTH TO GWINN AND MUNISING.
UPGRADED AREAS IN THE CNTRL CWA TO A WINTER STORM WARNING FOR EXPECTED
5-8" OF SNOW FALLING DURING THE DAYTIME HOURS AND THIS WILL CERTAINLY
IMPACT THE EVENING COMMUTE. OTHER THAN THE FAR EAST... WHERE GUSTY
SOUTH WINDS ARE STILL RESULTING IN BLSN AND WILL DO SO INTO THE
AFTN...WINDS ARE MAINLY LIGHT WITH THIS SYSTEM. FOR THE OTHER AREAS
AWAY FM THE CNTRL CWA KEPT THE ADVY GOING. ENDING TIME OF THESE
HEADLINES STILL LOOKS GOOD AT 00Z THIS EVENING.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 545 AM EST THU JAN 30 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A CLOSED MID LEVEL LOW
OVER NRN ONTARIO. IN THE BAND OF DEEP LAYER FORCING ASSOCIATED WITH
FEATURE...RADAR IMAGERY HAS SHOWN GOOD RADAR RETURNS FOR THE LAST
FEW HRS OVER LAKE SUPERIOR EXTENDING INTO PORTIONS OF THE ERN FCST
AREA. LOW-LEVEL DRY AIR HAS PROBABLY PREVENTED MUCH SNOW FROM
REACHING THE GROUND...AND MDOT WEBCAM/WEATHER STATION AT SENEY
INDICATES NOT MUCH GOING ON THERE DESPITE RADAR RETURNS. FARTHER N
TOWARD GRAND MARAIS...HAVE TO BELIEVE THERE IS SNOW FALLING IN THAT
AREA BASED ON INTENSITY OF RADAR RETURNS. COLD FRONT ASSOCIATED WITH
ONTARIO SYSTEM IS PASSING ACROSS WRN LAKE SUPERIOR. TO THE W...
ATTENTION IS ON SHORTWAVE MOVING ACROSS THE NRN PLAINS. AT THE
SFC...A LOW PRES WAVE HAS DEVELOPED ALONG THE SE SD/NE NEBRASKA
BORDER. AS SHORTWAVE MOVES E...SFC WAVE WILL TRACK ALONG COLD FRONT
MOVING ACROSS UPPER MI TODAY...PRODUCING A WIDESPREAD SNOW FOR MUCH
OF UPPER MI.
MODEL GUIDANCE HAS DEFINITELY TRENDED N AND W WITH SNOW BAND THAT
WILL ACCOMPANY SHORTWAVE...AND PCPN AMOUNTS HAVE TRENED UP AS WELL.
OVERALL...A GOOD SNOW EVENT APPEARS TO BE SHAPING UP TODAY. RATHER
STRONG DEEP LAYER FORCING PER QVECTORS IS INDICATED TO SHIFT ACROSS
THE AREA IN CONCERT WITH A BAND OF LOW-MID FRONTOGENESIS. AT THE
UPPER LEVELS...THERE ARE INDICATIONS OF SOME UPPER JET COUPLING BTWN
THE RIGHT ENTRANCE OF JET ASSOCIATED WITH NRN ONTARIO MID LEVEL LOW
AND LEFT EXIT OF JET ASSOCIATED WITH APPROACHING SHORTWAVE. THIS
COMES TOGETHER RIGHT OVER UPPER MI. MIXING RATIOS OF 2G/KG ARE NOTED
AROUND 700MB...SUGGESTING POTENTIAL FOR AROUND 4 INCHES OF SNOW.
HOWEVER...GIVEN SOME OF THE FORCING MECHANISMS NOTED ABOVE...
DEFINITELY HAVE CONCERN THAT AMOUNTS COULD REACH 6 INCHES OR
MORE...ESPECIALLY IF FOCUSED FRONTOGENETICAL FORCING DEVELOPS. SOME
HIGH RES MODEL GUIDANCE SUGGESTS THIS POTENTIAL COULD OCCUR ROUGHLY
ALONG AN AXIS FROM IRON RIVER TO MARQUETTE. HOURLY RUC13 MODEL RUNS
HAVE BEEN BEEFING UP PCPN AMOUNTS. 09Z RUN HAS AROUND 0.5 INCHES
ALONG THE AXIS MENTIONED. WILL BE SOMETHING TO MONITOR AS THE SNOW
AREA BECOMES ORGANIZED AND MORE INTENSE WHILE MOVING INTO UPPER MI.
HAVE EXPANDED WINTER WX ADVY TO COVER ALL BUT NRN HOUGHTON/KEWEENAW
COUNTIES TODAY. FORTUNATELY...THE STRONG WINDS NOW OCCURRING
DOWNWIND OF LAKE MI WILL BE SUBSIDING AS THE HEAVIER SNOW ARRIVES.
IN THE END...BLSN MAY NOT BE MUCH OF A PLAYER ANYWHERE DURING THE
MAIN PERIOD OF SNOWFALL. FOR SNOWFALL...EXPECT A GENERAL 3 TO 5 INCH
SNOWFALL ACROSS THE ADVY AREA WITH THE HEAVIEST SNOW PROBABLY IN A
WSW TO ENE BAND FROM ERN GOGEBIC/IRON/DICKINSON COUNTIES TO
BARAGA/MARQUETTE/ALGER COUNTIES.
SNOW WILL QUICKLY WIND DOWN/END FROM W TO E MID AFTN TO EARLY
EVENING. WNW TO W FLOW LES WILL FOLLOW TONIGHT AS 850MB TEMPS FALL
TO -16 TO -20C. HOWEVER...SHARP DROP OF INVERSION TO 3-4KFT COMBINED
WITH DRIER AIR SHOULD GREATLY LIMIT INTENSITY OF LES. ICE COVER ON
LAKE SUPERIOR WILL BE NEGATIVE FACTOR AS WELL. TEMPS ARE TRICKY. IF
WIND DECOUPLE AND CLOUD COVER CLEARS OUT SUFFICIENTLY...TEMPS WILL
PLUMMET AWAY FROM LAKE EFFECT AREAS. TRADITIONAL COLD SPOTS COULD
EASILY FALL WELL DOWN INTO THE -20S. FCST REFLECTS A CONSERVATIVE
APPROACH WITH TEMPS MAINLY IN THE SINGLE DIGITS TO LOW TEENS BELOW
ZERO. TEMPS SHOULD STAY ABOVE ZERO OVER THE FAR NE FCST AREA. WIND
CHILL MAY BE NEAR ADVY CRITERIA OVER PORTIONS OF THE W LATE
TONIGHT.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 519 AM EST THU JAN 30 2014
WILL START OUT WITH MAINLY ZONAL FLOW ALOFT FRIDAY MORNING. THAT
WILL QUICKLY CHANGE TO SW FLOW FRIDAY EVENING IN RESPONSE TO THE
MAIN 500MB LOW SHIFTING INTO N HUDSON BAY/QUEBEC...AND THE NEXT WAVE
SINKING IN FROM ONTARIO. QUICKENED THE END TO THE LIKELY POPS OVER
THE KEWEENAW PENINSULA...AND NEAR/EAST OF GRAND MARAIS FRIDAY AS SFC
WINDS BECOME MORE SW-W CUTTING OFF THE FLOW OF LINGERING MOISTURE
OFF LAKE SUPERIOR. HIGH TEMPS WILL STRUGGLE TO RISE INTO THE DOUBLE
DIGITS ABOVE ZERO FRIDAY...AND DEPENDING ON THE EXTENT OF ICE
COVERAGE OVER W LAKE SUPERIOR...MAY REMAIN IN THE LOW SINGLE DIGITS
ABOVE ZERO ACROSS THE W THIRD OF THE CWA.
GIVEN LOWS BOTTOMING OUT IN THE -10 TO 0 RANGE FRIDAY NIGHT/SATURDAY
MORNING...COULD HAVE A FEW POCKETS OF NEAR 20F WIND CHILL READINGS
OVER THE W HALF OF THE CWA...EVEN WITH LIGHT WINDS AVERAGING 5KTS OR
LESS. ALTHOUGH THERE WILL BE A COUPLE OF PERIODS OF WIND CHILL
VALUES IN THE 15-20 DEGREE RANGE...WILL LEAVE IT OUT OF THE HWO FOR
NOW...PARTICULARLY IN THE EXTENDED PERIOD WHERE OUR WIND FCST TENDS
TO BE TOO HIGH TO BEGIN WITH.
THE SW TO NE ORIENTED 500MB TROUGH SET UP FROM UT/CO TO FAR SE
MANITOBA SATURDAY AFTERNOON WILL SWEEP ACROSS THE UPPER GREAT LAKES
SATURDAY NIGHT INTO EARLY SUNDAY. CUT BACK ON THE S STREAM SLIGHT
CHANCE TO CHANCE POPS FOR SATURDAY AFTERNOON AND EVENING OVER THE S
AND E CWA. FCST MODELS LOOK TO BE CONSOLIDATING ON A SFC LOW TRACK
FROM N TX SATURDAY MORNING TO S/CENTRAL IL AT 18Z..AND N IN TO THE
LOWER GREAT LAKES AT 00Z SUNDAY. WHILE SOME SNOW WILL BE POSSIBLE ON
THE BACK SIDE OF THIS LOW SATURDAY AFTERNOON AND EARLY EVENING...IT
LOOKS LIKE THE BEST CHANCE WILL REMAIN TO OUR SE.
COLDER AIR SLIDING IN HOWEVER WILL BRING BACK A CHANCE OF LES TO THE
W FROM SATURDAY AFTERNOON...ON NW TO WNW WINDS AS 850MB TEMPS SLIDE
BACK INTO THE -15 TO -20C RANGE. WILL NOT GO TOO HIGH ON POPS FOR
SATURDAY AFTERNOON ON LES WISE...AS NOTED ABOVE...IT WILL GREATLY
DEPEND ON THE EXTENT OF ICE COVER ACROSS LAKE SUPERIOR. NO
SIGNIFICANT SNOW OR EXTREME /WIND CHILL WARNING/ COLD EVENTS ARE
FIGURED THROUGH THE REST OF THE PERIOD. THE NEXT POTENTIAL FOR
SYSTEM SNOW WILL ONCE AGAIN CLIP US TO THE S TUESDAY NIGHT AS THE
SFC LOW TRACKS UP THE OH VALLEY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1241 PM EST THU JAN 30 2014
A DISTURBANCE MOVING ALONG A COLD FRONT PUSHING ACROSS UPPER MI WILL
BRING SNOW TO THE AREA THIS AFTN. EXPECT LIFR/IFR IN OCCASIONALL
HEAVIER SNOW. THE WORST CONDITIONS THIS AFTERNOON WILL BE AT KSAW.
AFTER THE DISTURBANCE DEPARTS...MVFR CONDITIONS WILL RETURN THIS
EVENING. BEST CHC FOR MORE PERSISTENT SHSN/IFR VIS WILL BE AT THE
MORE EXPOSED KCMX LOCATION WITH WNW FLOW BEHIND FROPA PRESENTING AN
UPSLOPE WIND COMPONENT...BUT ICE COVERAGE OVER WRN LAKE SUPERIOR
MIGHT LIMIT THE COVERAGE/INTENSITY OF THESE SHSN. DOWNSLOPE NATURE
OF THIS FLOW WILL RESULT IN VFR CONDITIONS DEVELOPING AT KSAW THIS
EVENING. VFR CONDITIONS WILL RETURN TO KIWD OVERNIGHT IF NOT SOONER
AS WINDS BACK SOME. EXPECT VFR CONDITIONS AT ALL TERMINALS FOR FRIDAY
WITH LIGHT WINDS.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 256 AM EST THU JAN 30 2014
GALE FORCE GUSTS TO 35 KNOTS WILL REMAIN POSSILE EARLY THIS MORNING
E. WHILE HEAVY FREEZING SPRAY WILL BE LIMITED ELSEHWERE DUE
SIGNIFICANT ICE COVERING THE WATER...HEAVY FREEZING SPRAY WILL
REMAIN A CONCERN OVER E PORTIONS OF LAKE SUPERIOR THROUGH FRIDAY. A
FEW GALE FORCE GUSTS WILL ALSO BE POSSIBLE TONIGHT.
A LOW OVER CENTRAL ONTARIO WILL SHIFT E OF JAMES BAY THIS
EVENING...PULLING A TROUGH ACROSS LAKE SUPERIOR TODAY. HIGH PRESSURE
WILL THEN MOVE SE FROM ALBERTA TO S WI BY FRIDAY...WHILE BRINGING A
WEAK RIDGE OVER LAKE SUPERIOR. THEN ON SATURDAY...A TROUGH WILL MOVE
E ACROSS THE UPPER GREAT LAKES. THIS WILL BE FOLLOWED BY A HIGH OVER
THE MID MS VALLEY...WHICH WILL PASS A RIDGE ACROSS LAKE SUPERIOR ON
SUNDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER STORM WARNING UNTIL 7 PM EST /6 PM CST/ THIS EVENING FOR
MIZ005-006-011>013.
WINTER WEATHER ADVISORY UNTIL 7 PM EST /6 PM CST/ THIS EVENING
FOR MIZ004-007-010-014-085.
WINTER WEATHER ADVISORY UNTIL 4 PM EST /3 PM CST/ THIS AFTERNOON
FOR MIZ002-009-084.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING UNTIL 7 PM EST FRIDAY FOR LSZ266.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...JLA
SHORT TERM...ROLFSON
LONG TERM...KF
AVIATION...JLA
MARINE...KF
AREA FORECAST DISCUSSION...CORRECTED
NWS PORTLAND OR
229 PM PST THU JAN 30 2014
CORRECTED LONG TERM DISCUSSION
.SYNOPSIS...A PAIR OF WEAK UPPER LEVEL DISTURBANCES WILL DRIFT
SOUTHEASTWARD ACROSS WASHINGTON AND OREGON TONIGHT AND FRIDAY. THIS
WILL KEEP PLENTY OF SHOWERS AROUND THE FORECAST AREA...ESPECIALLY
ACROSS THE HIGHER TERRAIN. SNOW LEVELS ARE DOWN INTO THE HIGHER
FOOTHILL ELEVATIONS...SO PRECIPITATION WILL FALL AS SNOW FOR THE
CASCADE PASSES. HIGH PRESSURE WILL RESULT IN DRIER WEATHER FOR THE
WEEKEND...THOUGH NIGHT AND MORNING FOG WILL PROBABLY FORM IN THE
VALLEYS. TEMPERATURES LIKELY TREND COOLER THAN NORMAL FOR NEXT
WEEK...WITH A GENERALLY DRY PATTERN CONTINUING WELL INTO THE WEEK.
&&
.SHORT TERM...TONIGHT THROUGH SUNDAY...NWS DOPPLER RADAR IMAGERY
LOOKS PRETTY SIMILAR THIS AFTERNOON WHEN COMPARED TO YESTERDAY
AFTERNOON...WITH SHOWERS INCREASING ACROSS SW WASHINGTON AND
SPREADING SOUTHEAST TOWARD THE PORTLAND METRO. EXPECT THIS TREND TO
CONTINUE AS AN UPPER LEVEL DISTURBANCE OFF THE WASHINGTON COAST MOVES
SE INTO NORTHERN OREGON.
THERE WERE QUITE A FEW SUNBREAKS TODAY IN THE WILLAMETTE VALLEY...
ALLOWING TEMPS TO CLIMB INTO THE LOWER 50S IN SPOTS. MEANWHILE TEMPS
ALOFT CONTINUE TO COOL...WITH THE LATEST RAP ANALYZING A -33 DEG C
COLD POOL AT 500 MB NEAR ASTORIA THE PAST HOUR. 12Z NAM BUFR
SOUNDINGS REFLECT THIS COLD POOL ALOFT WELL...WITH FAIRLY STEEP LAPSE
RATES EXTENDING UP TO AROUND 15KFT. THE UPPER DISTURBANCE MOVING
THROUGH WILL PROVIDE A LITTLE EXTRA LIFT...AND IT IS POSSIBLE SOME OF
THE MORE VIGOROUS CELLS WILL REACH 20KFT. BELIEVE THIS IS ENOUGH TO
WARRANT A SLIGHT CHANCE OF THUNDER FOR OUR NORTHERN ZONES THIS
AFTERNOON AND EVENING. IF ANY THUNDERSTORMS DEVELOP...EXPECT THEM TO
BE SHORT-LIVED PERHAPS PRODUCING ONE OR TWO LIGHTNING STRIKES BEFORE
COLLAPSING. IN THE COOL AIR MASS SOME SMALL HAIL IS POSSIBLE IN
HEAVIER SHOWERS AS WELL. ALL IN ALL...A TYPICAL WINTER POST-FRONTAL
ENVIRONMENT FOR THE PAC NW.
SNOW LEVELS WILL BE IN THE 2000-2500 FT RANGE AS THESE SHOWERS MOVE
INTO THE CASCADES. 12Z/18Z NAM AND 12Z UW-WRF SUGGEST ABOUT 3-6
INCHES OF SNOW OVERNIGHT...WITH THE BEST TOTALS GENERALLY MT HOOD
NORTHWARD. GIVEN THE TRACK OF THE UPPER LOW IT APPEARS OROGRAPHICS
WILL BE GRADUALLY EASING...JUST ENOUGH TO KEEP THE CASCADES FROM
GETTING ENOUGH SNOW TO WARRANT A SNOW ADVISORY. NONETHELESS THE
CASCADE PASSES WILL LIKELY BE SNOW COVERED TONIGHT...SO CAUTION IS
ADVISED.
ANOTHER WEAK UPPER LEVEL SYSTEM WILL QUICKLY FOLLOW...CAUSING SHOWERS
TO CONTINUE INTO FRIDAY. IN FACT PRECIPITATION MAY BRIEFLY TURN MORE
STRATIFORM FRIDAY MORNING AS TODAYS UPPER DISTURBANCE MOVES THROUGH
EASTERN OREGON AND THE SECOND ONE PASSES OFFSHORE. 12Z AND 18Z NAM
CROSS SECTIONS SHOW A LITTLE ENHANCED LOW-LEVEL FRONTOGENESIS AND
ASSOCIATED LIFT OVER THE WILLAMETTE VALLEY FRI MORNING...ALSO
POINTING TOWARD THE POSSIBILITY OF STEADIER PRECIPITATION. THIS WILL
NEED TO BE WATCHED CLOSELY AS IT COULD PUSH SOME OF OUR FOOTHILLS
ZONES INTO SNOW ADVISORY CRITERIA DURING THE COOLEST PART OF THE DAY.
AFTER FRIDAY HIGH PRESSURE BUILDS IN AND WE GRADUALLY DRY OUT...WITH
JUST SOME LINGERING MOUNTAIN SHOWERS FRIDAY NIGHT ENDING SAT MORNING.
LOW-LEVEL FLOW WILL REMAIN RATHER LIGHT...SO THERE MAY BE SOME FOG
SAT MORNING AND AN EVEN BETTER CHANCE FOR MORE WIDESPREAD FOG SAT
NIGHT/SUN MORNING. FOR NOW OUR HIGH TEMPS SHOW MID 40S IN THE INLAND
VALLEYS SUNDAY...BUT IT IS POSSIBLE TEMPS MAY NOT GET OUT OF THE 30S
IF THE FOG AND LOW CLOUDS ARE THICK ENOUGH. WEAGLE
.LONG TERM...SUNDAY NIGHT THROUGH THURSDAY...FEW CHANGES. UPPER
RIDGE/QUASI-SPLIT FLOW REGIME WILL PERSIST OVER THE PAC NW THROUGH
THE EXTENDED. THIS CAUSES MORE UNCERTAINTY THAN NORMAL FOR THE
EXTENDED FORECAST. A COUPLE OF DISTURBANCES TRY TO MOVE THROUGH THE
REGION NEXT WEEK...HOWEVER GIVEN THE WEAK FLOW UNCERTAINTY IS HIGH
WITH REGARD TO THE TRACK OF THESE FEATURES AND THE ASSOCIATED
PRECIPITATION. THEREFORE CONFIDENCE IN THE PRECIPITATION FORECAST
BEYOND MONDAY IS LOW. DESPITE THIS...MODELS DO AGREE THAT
TEMPERATURES WILL BE DECREASING OVERALL WITH INVERSION CONDITIONS
UNLIKELY. MAIN CHANGES WERE TO BRING TEMPERATURES DOWN THROUGH THE
WEEK...WITH BOTH HIGHS AND LOWS LOOKING TO BE 10F BELOW NORMAL
MONDAY NIGHT THROUGH THURSDAY. BURGESS
&&
.AVIATION...WIDESPREAD VFR CONDITIONS ACROSS REGION THIS AFTERNOON
WITH ONLY A FEW POCKETS OF MVFR CIGS. AS SHOWERS INCREASE LATER
TODAY AND EVENING...AREAS OF MVFR CIGS WILL INCREASE. MAY EVEN SEE
A PERIOD BETWEEN 04Z AND 10Z WHERE PRECIP IS MORE STEADY STATE...
MAINLY N OF A KTMK TO KSLE LINE. OTHERWISE...EXPECT WIDESPREAD
MVFR CIGS TO SPREAD ACROSS REGION LATER THIS EVENING AND PERSIST
INTO FRI AM. CAN NOT ELIMINATE AN ISOLATED TS ALONG THE COAST AND
OVER PAC UNTIL 06Z. MTNS FREQUENTLY OBSCURED IN CLOUDS TONIGHT.
KPDX AND APPROACHES...VFR CONDITIONS INTO EARLY THIS EVENING. AS
SHOWERS INCREASE...WILL SEE CIGS LOWER BACK TO MVFR RANGE...MOSTLY
NEAR 2000 TO 2500 FT AFTER 06Z-08Z.
&&
.MARINE...W TO NW WINDS GENERALLY 15 TO 20 KT TODAY. DECENT
GRADIENT OVER THE N COASTAL WATERS...AND COMBINED WITH SHOWERS
SEEMS REASONABLE TO CONTINUE WITH THE GUSTS OVER THE N ORE/S WASH
COASTAL WATERS. BUT S OF CASCADE HEAD...WINDS STAY UNDER 20 KT.
SEAS RUNNING 9 TO 11 FT TODAY INTO THIS EVENING. MAY DROP BACK TO
9 FT AT TIMES...BUT WITH NW WINDS BLOWING OVER THE NE PAC THE
FETCH AREA WILL CONTINUE TO CLIP THE OUTER WATERS THROUGH THIS
EVENING. SEAS WILL DROP BELOW 10 FT LATER TONIGHT.
HIGH PRES WILL BUILD OVER REGION FRI AND INTO THE WEEKEND...WITH
WINDS 15 KT OR LESS AND SEA SUBSIDING TO 5 OR 6 FT.
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL 9 PM THIS EVENING FOR
N COASTAL WATERS...OR CAPE SHOALWATER TO CASCADE HEAD.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS THROUGH THIS EVENING
ON ALL COASTAL WATERS.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL
8 PM THIS EVENING...AND 4 AM TO 8 AM FRI.
&&
$$
MORE WEATHER INFORMATION ONLINE AT..
HTTP://WEATHER.GOV/PORTLAND
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.PORTLAND.GOV
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM
THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY
REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION
NWS PORTLAND OR
224 PM PST THU JAN 30 2014
.SYNOPSIS...A PAIR OF WEAK UPPER LEVEL DISTURBANCES WILL DRIFT
SOUTHEASTWARD ACROSS WASHINGTON AND OREGON TONIGHT AND FRIDAY. THIS
WILL KEEP PLENTY OF SHOWERS AROUND THE FORECAST AREA...ESPECIALLY
ACROSS THE HIGHER TERRAIN. SNOW LEVELS ARE DOWN INTO THE HIGHER
FOOTHILL ELEVATIONS...SO PRECIPITATION WILL FALL AS SNOW FOR THE
CASCADE PASSES. HIGH PRESSURE WILL RESULT IN DRIER WEATHER FOR THE
WEEKEND...THOUGH NIGHT AND MORNING FOG WILL PROBABLY FORM IN THE
VALLEYS. TEMPERATURES LIKELY TREND COOLER THAN NORMAL FOR NEXT
WEEK...WITH A GENERALLY DRY PATTERN CONTINUING WELL INTO THE WEEK.
&&
.SHORT TERM...TONIGHT THROUGH SUNDAY...NWS DOPPLER RADAR IMAGERY
LOOKS PRETTY SIMILAR THIS AFTERNOON WHEN COMPARED TO YESTERDAY
AFTERNOON...WITH SHOWERS INCREASING ACROSS SW WASHINGTON AND
SPREADING SOUTHEAST TOWARD THE PORTLAND METRO. EXPECT THIS TREND TO
CONTINUE AS AN UPPER LEVEL DISTURBANCE OFF THE WASHINGTON COAST MOVES
SE INTO NORTHERN OREGON.
THERE WERE QUITE A FEW SUNBREAKS TODAY IN THE WILLAMETTE VALLEY...
ALLOWING TEMPS TO CLIMB INTO THE LOWER 50S IN SPOTS. MEANWHILE TEMPS
ALOFT CONTINUE TO COOL...WITH THE LATEST RAP ANALYZING A -33 DEG C
COLD POOL AT 500 MB NEAR ASTORIA THE PAST HOUR. 12Z NAM BUFR
SOUNDINGS REFLECT THIS COLD POOL ALOFT WELL...WITH FAIRLY STEEP LAPSE
RATES EXTENDING UP TO AROUND 15KFT. THE UPPER DISTURBANCE MOVING
THROUGH WILL PROVIDE A LITTLE EXTRA LIFT...AND IT IS POSSIBLE SOME OF
THE MORE VIGOROUS CELLS WILL REACH 20KFT. BELIEVE THIS IS ENOUGH TO
WARRANT A SLIGHT CHANCE OF THUNDER FOR OUR NORTHERN ZONES THIS
AFTERNOON AND EVENING. IF ANY THUNDERSTORMS DEVELOP...EXPECT THEM TO
BE SHORT-LIVED PERHAPS PRODUCING ONE OR TWO LIGHTNING STRIKES BEFORE
COLLAPSING. IN THE COOL AIR MASS SOME SMALL HAIL IS POSSIBLE IN
HEAVIER SHOWERS AS WELL. ALL IN ALL...A TYPICAL WINTER POST-FRONTAL
ENVIRONMENT FOR THE PAC NW.
SNOW LEVELS WILL BE IN THE 2000-2500 FT RANGE AS THESE SHOWERS MOVE
INTO THE CASCADES. 12Z/18Z NAM AND 12Z UW-WRF SUGGEST ABOUT 3-6
INCHES OF SNOW OVERNIGHT...WITH THE BEST TOTALS GENERALLY MT HOOD
NORTHWARD. GIVEN THE TRACK OF THE UPPER LOW IT APPEARS OROGRAPHICS
WILL BE GRADUALLY EASING...JUST ENOUGH TO KEEP THE CASCADES FROM
GETTING ENOUGH SNOW TO WARRANT A SNOW ADVISORY. NONETHELESS THE
CASCADE PASSES WILL LIKELY BE SNOW COVERED TONIGHT...SO CAUTION IS
ADVISED.
ANOTHER WEAK UPPER LEVEL SYSTEM WILL QUICKLY FOLLOW...CAUSING SHOWERS
TO CONTINUE INTO FRIDAY. IN FACT PRECIPITATION MAY BRIEFLY TURN MORE
STRATIFORM FRIDAY MORNING AS TODAYS UPPER DISTURBANCE MOVES THROUGH
EASTERN OREGON AND THE SECOND ONE PASSES OFFSHORE. 12Z AND 18Z NAM
CROSS SECTIONS SHOW A LITTLE ENHANCED LOW-LEVEL FRONTOGENESIS AND
ASSOCIATED LIFT OVER THE WILLAMETTE VALLEY FRI MORNING...ALSO
POINTING TOWARD THE POSSIBILITY OF STEADIER PRECIPITATION. THIS WILL
NEED TO BE WATCHED CLOSELY AS IT COULD PUSH SOME OF OUR FOOTHILLS
ZONES INTO SNOW ADVISORY CRITERIA DURING THE COOLEST PART OF THE DAY.
AFTER FRIDAY HIGH PRESSURE BUILDS IN AND WE GRADUALLY DRY OUT...WITH
JUST SOME LINGERING MOUNTAIN SHOWERS FRIDAY NIGHT ENDING SAT MORNING.
LOW-LEVEL FLOW WILL REMAIN RATHER LIGHT...SO THERE MAY BE SOME FOG
SAT MORNING AND AN EVEN BETTER CHANCE FOR MORE WIDESPREAD FOG SAT
NIGHT/SUN MORNING. FOR NOW OUR HIGH TEMPS SHOW MID 40S IN THE INLAND
VALLEYS SUNDAY...BUT IT IS POSSIBLE TEMPS MAY NOT GET OUT OF THE 30S
IF THE FOG AND LOW CLOUDS ARE THICK ENOUGH. WEAGLE
.LONG TERM...SUNDAY NIGHT THROUGH THURSDAY...FEW CHANGES. UPPER
RIDGE/QUASI-SPLIT FLOW REGIME WILL PERSIST OVER THE PAC NW THROUGH
THE EXTENDED. THIS MAKES FOR MORE UNCERTAINTY THAN NORMAL FOR NEXT
WEEK. A FEW WEAK DISTURBANCES TRY TO MOVE THROUGH THE WEAK FLOW...
HOWEVER PRECIPITATION CHANCES LOOK TO REMAIN WELL BELOW CLIMATOLOGY
THROUGH MOST OF THE PERIOD. THE MAIN CHANGES WERE TO BRING
TEMPERATURES DOWN THROUGH THE WEEK...WITH HIGHS AND LOWS LOOKING TO
BE AROUND 10F BELOW NORMAL MONDAY NIGHT THROUGH THURSDAY. BURGESS
&&
.AVIATION...WIDESPREAD VFR CONDITIONS ACROSS REGION THIS AFTERNOON
WITH ONLY A FEW POCKETS OF MVFR CIGS. AS SHOWERS INCREASE LATER
TODAY AND EVENING...AREAS OF MVFR CIGS WILL INCREASE. MAY EVEN SEE
A PERIOD BETWEEN 04Z AND 10Z WHERE PRECIP IS MORE STEADY STATE...
MAINLY N OF A KTMK TO KSLE LINE. OTHERWISE...EXPECT WIDESPREAD
MVFR CIGS TO SPREAD ACROSS REGION LATER THIS EVENING AND PERSIST
INTO FRI AM. CAN NOT ELIMINATE AN ISOLATED TS ALONG THE COAST AND
OVER PAC UNTIL 06Z. MTNS FREQUENTLY OBSCURED IN CLOUDS TONIGHT.
KPDX AND APPROACHES...VFR CONDITIONS INTO EARLY THIS EVENING. AS
SHOWERS INCREASE...WILL SEE CIGS LOWER BACK TO MVFR RANGE...MOSTLY
NEAR 2000 TO 2500 FT AFTER 06Z-08Z.
&&
.MARINE...W TO NW WINDS GENERALLY 15 TO 20 KT TODAY. DECENT
GRADIENT OVER THE N COASTAL WATERS...AND COMBINED WITH SHOWERS
SEEMS REASONABLE TO CONTINUE WITH THE GUSTS OVER THE N ORE/S WASH
COASTAL WATERS. BUT S OF CASCADE HEAD...WINDS STAY UNDER 20 KT.
SEAS RUNNING 9 TO 11 FT TODAY INTO THIS EVENING. MAY DROP BACK TO
9 FT AT TIMES...BUT WITH NW WINDS BLOWING OVER THE NE PAC THE
FETCH AREA WILL CONTINUE TO CLIP THE OUTER WATERS THROUGH THIS
EVENING. SEAS WILL DROP BELOW 10 FT LATER TONIGHT.
HIGH PRES WILL BUILD OVER REGION FRI AND INTO THE WEEKEND...WITH
WINDS 15 KT OR LESS AND SEA SUBSIDING TO 5 OR 6 FT.
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL 9 PM THIS EVENING FOR
N COASTAL WATERS...OR CAPE SHOALWATER TO CASCADE HEAD.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS THROUGH THIS EVENING
ON ALL COASTAL WATERS.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL
8 PM THIS EVENING...AND 4 AM TO 8 AM FRI.
&&
$$
MORE WEATHER INFORMATION ONLINE AT..
HTTP://WEATHER.GOV/PORTLAND
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.PORTLAND.GOV
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM
THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY
REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
1054 AM CST THU JAN 30 2014
.UPDATE...A SWATH OF LIGHT TO MODERATE SNOW UPSTREAM IS CURRENTLY
ENTERING SOUTH CENTRAL WISCONSIN...REDUCING VISIBILITIES AS FAR DOWN
AS A 3/4 TO A 1/4 MILE AT TIMES. A BAND MOVED THROUGH A BIT AHEAD OF
THIS SWATH HOWEVER...DRY AIR HAS LIMITED HOW MUCH PRECIP COULD MAKE
IT TO THE SURFACE. SFC OBS AND VIEW FROM OUR WINDOW SUPPORT ONLY
VERY LIGHT SNOW/FLURRIES...IF ANYTHING FROM THE RETURNS ASSOCIATED WITH
THAT BAND. MSAS ANALYZES SHOWS THE SURFACE LOW CENTERED OVER NORTH
CENTRAL IA/SOUTHEAST MN.
OTHERWISE...FORECAST IS GENERALLY ON TRACK. MAIN CONCERNS ARE
POPS/WX AND WINDS TODAY...OF WHICH BOTH ARE ON TRACK AND MATCH WELL
WITH LATEST HI-RES GUIDANCES. DRY AIR IMPEDING PRECIP EARLIER IS
SLOWING BECOMING SATURATED AND WILL ALLOW THE AFOREMENTIONED SWATH
OF SNOW TO REACH THE GROUND ACROSS THE CWA SHORTLY. BLOWING SNOW
WILL BE A CONCERN WITH THE STRONG WINDS AHEAD OF THE LOW. 1000-850
MEAN LAYER WINDS APPROACHING AND EXCEEDING 40 KTS LATE MORNING/EARLY
AFTERNOON. THOUGH THE RAP13 BUFKIT SOUNDINGS DONT HAVE AS STRONG OF
WINDS IN THE MEAN MIXED LAYER. REGARDLESS...PROXIMITY SOUNDINGS SHOW
STRONG SUPPORT FOR MOMENTUM TRANSFER AND FOR THESE UPPER LEVEL WINDS
TO MIX DOWN TO THE SURFACE.
&&
.AVIATION/18Z TAFS/...STILL LOOKS LIKE A RELATIVELY QUICK SHOT OF
SNOW LATE MORNING INTO THE AFTERNOON. BASED ON UPSTREAM
OBS...VSBYS MAY BRIEFLY GO DOWN TO AS LOW AS 1/4 MILE...WITH AN
INCH OR TWO OF SNOW POSSIBLE BY MID AFTERNOON. BLOWING SNOW MAY
KEEP VISIBILITIES BELOW 6 MILES THROUGH LATE AFTERNOON OR EARLY
EVENING UNTIL WINDS BEGIN TO EASE. VFR CONDITIONS SHOULD RETURN BY
LATE EVENING AS DRIER AIR WORKS INTO THE AREA AND CIGS IMPROVE.
VFR CONDITIONS THEN EXPECTED THROUGH THE DAY FRIDAY...WITH MORE
SNOW THEN POSSIBLE FRIDAY NIGHT INTO SATURDAY.
&&
.PREV DISCUSSION... /ISSUED 524 AM CST THU JAN 30 2014/
TODAY...FORECAST CONFIDENCE IS MEDIUM.
IT WILL DEFINITELY BE WINDY AND THERE WILL BE ACCUMULATING SNOW
DURING THE MIDDLE PART OF THE DAY. BASED ON TRACKING OF THE MOVEMENT
OF HIGHER REFLECTIVITY SNOW ON AREA RADARS TO THE WEST...HAVE KEPT
CURRENT TIMING OF SNOW INTO THE WESTERN CWA AROUND 14Z-15Z...
REACHING BERLIN...MADISON AND MONROE AROUND 16Z...PLYMOUTH...
WAUKESHA AND LAKE GENEVA AROUND 17Z...AND MILWAUKEE TO KENOSHA BY
18Z.
SOME CONCERN WITH LATEST HRRR AND RAP THAT KEEP THE SNOW FROM
MADISON AND WEST THROUGH 18Z...SO WILL MONITOR OBS/RADAR AND ADJUST
IF NECESSARY. LEADING AREA OF RETURNS WITH STRONG ISENTROPIC LIFT
OVER SRN MN AND N CENTRAL IOWA...BUT NO GROUND TRUTH WITH 9-10K FT
CEILINGS REFLECTING DRY LAYER BELOW 10K FT ON FORECAST SOUNDINGS
THAT WILL HAVE TO SATURATE BEFORE SNOW REACHES GROUND.
HAVE DROPPED SNOW ACCUMULATIONS A BIT AS NOT QUITE AS MUCH QPF USING
CONSENSUS MODEL AMOUNTS...WHICH WERE HIGHER THAN WPC...WHICH KEEPS
SNOW TOTALS IN THE 1 TO 2 INCH RANGE WITH THE HIGHER AMOUNTS NORTH
WITH BETTER FRONTOGENETIC FORCING...THOUGH AN ISOLATED 3 INCH TOTAL
NOT OUT OF THE QUESTION.
WINDS WILL BE AN ISSUE MAINLY AHEAD OF...AND AT THE ONSET OF THE
SNOW WITH 45-50KT WINDS AT 900-925 MB AHEAD OF LOW. SOME BLOWING AND
DRIFTING EXPECTED WITH THE STRONG WINDS EARLY THIS MORNING...BUT
WITH CURRENT OBS REMAINING AT 10SM WITH GUSTS TO 30 KNOTS...THINK
DRIFTING ON EAST-WEST ROADS IN OPEN AREAS WILL BE THE BIGGER
PROBLEM.
FORECAST SOUNDINGS DO NOT REACH THESE STRONGEST WINDS WITH THE
INVERSION LIMITING MIXING UP TO AROUND 1K FT. THIS WILL KEEP HIGHEST
SUSTAINED WINDS IN THE 20-25 MPH RANGE...AND GUSTS GENERALLY 30-35
MPH WITH A FEW 40 MPH.
NO HEADLINES AS SNOW AMOUNTS AND WINDS DO NOT SUPPORT EITHER AN
ADVISORY FOR SNOW OR WINDS ALONE...THOUGH A CASE COULD BE MADE FOR A
WINTER WEATHER ADVISORY FOR THE SNOW/WIND COMBINATION. GIVEN THAT
THE MAIN PERIOD OF ACCUMULATING SNOW WILL OCCUR DURING THE MIDDAY
HOURS AND NOT DURING EITHER THE MORNING OR EVENING RUSH HOURS...AND
WINDS WILL BE DECREASING AS SNOW MOVES IN...WILL CONTINUE TO
HIGHLIGHT THE TRICKY TRAVEL CONDITIONS WITH FREQUENT SPS ISSUANCES.
TONIGHT...FORECAST CONFIDENCE IS HIGH.
SNOW EXPECTED TO PUSH EAST OF FORECAST AREA BY 00Z WITH TEMPS
DROPPING BEHIND COLD FRONT. 925 MB TEMPS FALL TO THE TEENS BELOW
ZERO BY 12Z FRIDAY...SUPPORTING LOWS IN THE SINGLE DIGITS ABOVE IN
THE SOUTHEAST HALF OF THE CWA AND ZERO TO THE SINGLE DIGITS BELOW IN
THE NORTHWEST HALF. WIND CHILLS FRIDAY MORNING WILL BE BETWEEN -5
AND -15.
SHORT TERM...FRIDAY THROUGH SATURDAY NIGHT...FORECAST CONFIDENCE
IS HIGH.
SHORT TERM MODELS SHOW HIGH PRESSURE SLIDING EAST ACROSS THE
REGION ON FRIDAY. ECMWF/CANADIAN MODELS TRY TO NUDGE LIGHT QPF
INTO THE FAR SOUTHERN COUNTIES BY 00Z SATURDAY...WITH THE GFS JUST
SOUTH OF THE BORDER AND NAM FURTHER SOUTH INTO NORTHERN ILLINOIS.
THIS IS IN RESPONSE TO 500 MB VORTICITY MAXIMUM SLIDING INTO THE
AREA DURING THE AFTERNOON.
MID LEVELS ARE MOIST...BUT LOW LEVELS ARE DRY. KEPT LOW POPS IN
THE FAR SOUTH AND SOUTHEAST FRIDAY AFTERNOON PER COORDINATION WITH
NEIGHBORING OFFICES...THOUGH THIS COULD END UP BEING A DRY PERIOD.
COOL HIGHS IN THE TEENS ARE EXPECTED.
SHORT TERM MODELS THEN IN GENERAL AGREEMENT WITH BRINGING SURFACE
LOW NORTHEAST ACROSS MISSOURI FRIDAY NIGHT...THEN TO THE NORTHERN
OHIO AREA SATURDAY. MODELS BRING A 500 MB VORTICITY MAXIMUM
THROUGH THE REGION SATURDAY...ALONG WITH DECENT Q VECTOR
CONVERGENCE AND FRONTOGENESIS RESPONSE IN THE MID LEVELS. CANADIAN
IS TOO AGGRESSIVE FRIDAY NIGHT WITH QPF...AND FAVORED A SOMEWHAT
SLOWER BLEND OF GFS/ECMWF.
MODELS ALL BRING A SWATH OF LIGHT TO MODERATE QPF ACROSS MOST OF
THE AREA SATURDAY MORNING...LINGERING INTO THE AFTERNOON. NAM/GFS
FORECAST SOUNDINGS SHOWING SATURATION IN DEEP LAYER WITH DENDRITE
SNOW GROWTH ZONE BEING TAPPED. BROUGHT IN HIGH POPS INTO THE FAR
SOUTHEAST SATURDAY MORNING...WITH LIKELY IN THE SOUTHEAST HALF OF
THE AREA. KEPT SIMILAR POPS SATURDAY AFTERNOON. AMOUNTS OF 1 TO 2
INCHES NORTHWEST TO 3 TO 4 INCHES SOUTHEAST ARE ANTICIPATED AT
THIS TIME.
MAY SEE MORE SNOW IN THE SOUTHEAST IF MODELS TREND MORE TO THE
NORTH...AND A WINTER WEATHER ADVISORY MAY BE NEEDED FOR LATER
FRIDAY NIGHT INTO SATURDAY IN LATER FORECASTS. WILL CONTINUE TO
MENTION IN HAZARDOUS WEATHER OUTLOOK FOR NOW. COLD AIR ADVECTION
BRINGS DRIER AIR AND QUIET WEATHER INTO THE AREA SATURDAY
NIGHT...AS WELL AS COLDER TEMPERATURES.
LONG TERM...SUNDAY THROUGH WEDNESDAY...FORECAST CONFIDENCE IS
MEDIUM.
GFS/ECMWF AGREE ON SHOWING HIGH PRESSURE SLIDING EAST SOUTHEAST
ACROSS THE REGION SUNDAY INTO MONDAY. THIS SHOULD BRING QUIET
WEATHER TO THE AREA...ALONG WITH CONTINUED COLD TEMPERATURES.
MODELS THEN BRING A SURFACE LOW FROM THE FAR SOUTHERN PLAINS
ACROSS THE MID MISSISSIPPI RIVER VALLEY MONDAY NIGHT INTO
TUESDAY...THEN NORTHEASTWARD TUESDAY NIGHT INTO WEDNESDAY. GFS
BRINGS A SWATH OF QPF ACROSS THE AREA LATE MONDAY NIGHT INTO
TUESDAY EVENING...WITH THE ECMWF HOLDING OFF UNTIL TUESDAY
AFTERNOON AND NIGHT...ASSOCIATED WITH 500 MB VORTICITY MAXIMUM
AND MID LEVEL FRONTOGENESIS RESPONSE. THESE FEATURES REMAIN TO
THE SOUTH OF THE AREA...SO THERE IS SOME UNCERTAINTY WITH THE
EXACT PLACEMENT OF QPF THIS FAR OUT.
FOR NOW...KEPT CONSENSUS BLEND OF POPS GOING FOR MONDAY NIGHT
INTO WEDNESDAY. POPS MAY NEED TO BE RAISED LATER ON IF BETTER
MODEL AGREEMENT IS REACHED ON THIS SYSTEM. SEVERAL INCHES OF SNOW
IS POSSIBLE. COOL TEMPERATURES LINGER AS WELL.
AVIATION/12Z TAFS/...
LOOK FOR LOW-LEVEL WIND SHEAR TO CONTINUE WITH NEAR 40KT SPEED
DIFFERENTIAL FROM THE SURFACE UP TO 12K TO 14K FEET UNTIL AROUND
15Z AT KMSN...AND BETWEEN 17Z AND 18Z AT EASTERN TAF SITES. THE GUSTY
SOUTHWEST WINDS WILL CAUSE SOME DRIFTING OF THE CURRENT LIGHT
SNOW COVER OVER RUNWAYS THIS MORNING. THE WINDS WILL EASE A BIT
WITH THE APPROACH OF THE SURFACE TROUGH/COLD FRONT TRAILING FROM
LOW PRESSURE CROSSING CENTRAL WISCONSIN.
VFR CONDITIONS WILL RAPIDLY DETERIORATE WITH ACCUMULATING SNOW
AHEAD AND ALONG THE FRONT...WITH THE SNOW REACHING KMSN BETWEEN
16Z AND 17Z...KUES BETWEEN 17Z AND 18Z...AND KMKE AND KENW IN THE
18Z TO 19Z TIME FRAME. CIGS AND VSBYS WILL DIP TO MVFR LEVELS WITH
THE ONSET OF THE SNOW...DROPPING WITHIN AN HOUR OT TWO TO IFR WITH
OCCASIONAL LIFR VSBYS FOR A FEW HOURS...THEN BACK UP TO MVFR CIGS
AND VFR VSBYS AS THE SNOW ENDS WITH THE PASSAGE OF THE FRONT MID
TO LATE AFTERNOON. WEST TO NORTHWEST WINDS BEHIND THE FRONT WILL
NOT BE AS STRONG AS THE LOW WILL BE WEAKENING AS IT LIFTS
NORTHEAST OUT OF THE STATE. THE MVFR CIGS ARE EXPECTED TO SCATTER
OUT MID-EVENING...WITH VFR CONDITIONS EXPECTED FOR THE REMAINDER
OF THE FORECAST PERIOD.
MARINE...SATELLITE IMAGERY FROM POLAR ORBITER YESTERDAY AFTERNOON
SHOWED WEST WINDS HAD SHIFTED BROKEN ICE SHIELD OUT AT LEAST 10
MILES FROM SHORE. STILL NOT MUCH OPEN WATER TO BUILD WAVES...BUT
HEIGHTS CERTAINLY NOT ZERO. BRISK SOUTHWEST WINDS ARE EXPECTED TO BE
BORDERLINE GALE...BUT WITH OFFSHORE FLOW AND MINIMAL OPEN WATER FOR
MIXING UP TO STRONGER WINDS...WILL KEEP CURRENT SMALL CRAFT ADVISORY
GOING AND MENTION A FEW GALE GUSTS...WITH THE BEST POTENTIAL FROM
THIS MORNING THROUGH EARLY AFTERNOON. WINDS EASE AS SURFACE
TROUGH/COLD FRONT MOVE THROUGH THEN FREQUENT WEST WIND GUSTS TO 25
KTS FOR A BRIEF TIME EARLY THIS EVENING BEHIND FRONT. CURRENT END
TIME LOOKS GOOD.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 9 PM CST THIS EVENING FOR LMZ643>646.
&&
$$
UPDATE...DDV
TODAY/TONIGHT AND AVIATION/MARINE...REM
FRIDAY THROUGH WEDNESDAY...WOOD