Forecast Discussions mentioning any of
"HRRR" "RR" "RUC13" "RUC" received at GSD on 12/30/11
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
425 PM EST WED DEC 28 2011
.SHORT TERM...
TONIGHT THROUGH THURSDAY NIGHT
PAIR OF WEAK CLIPPER SYSTEMS TO IMPACT THE AREA IN THE SHORT TERM.
WATER VAPOR IMAGERY AND LATEST RUC ANALYSIS DEPICTING LEAD SHORT
WAVE OVER SOUTHERN MANITOBA AND MOVING INTO WESTERN ONTARIO. THIS
FEATURE EXPECTED TO WEAKEN/SHEAR OUT IN FAST MOVING NW FLOW PATTERN
AS IT DROPS DOWN INTO THE NORTHERN GREAT LAKES TONIGHT/THU AM.
RESULT SHOULD BE BETTER CHANCES FOR PRECIP TO REMAIN NORTH OF THE
AREA WHERE BETTER FORCING AND MOISTURE WILL BE PRESENT...BUT CLOSE
ENOUGH TO MAINTAIN SMALL CHANCE POPS FOR NORTHERN TWO THIRDS OF CWA.
MODELS INDICATING DECENT SFC/LOW LEVEL RESPONSE WITH THIS FIRST
SHORT WAVE RESULTING IN GOOD WAA IN ADVANCE OF THIS SYSTEM WHICH
WILL HAVE TEMPS SLOWLY RISING AFTER MIDNIGHT TONIGHT AND ALSO BRING
PRECIP TYPE INTO QUESTION. FCST SOUNDINGS SHOWING DECENT ELEVATED
WARM LAYER AND MORE FAVORABLE PROFILES IN SUPPORT OF LIQUID
PRECIP...AND WHILE 12Z SOUNDINGS FROM KOAX AND KSGF LEND CREDENCE TO
THIS SCENARIO...STILL NOT CONVINCED THAT MUCH LOW LEVEL WARMING WILL
BE REALIZED WITH FAST MOVING SYSTEM SO WILL KEEP WITH RA/SN MIX IN
WX GRIDS ATTM. 140KT JET COMING ONSHORE IN PACIFIC NW THIS MORNING
WILL DRIVE SECOND SHORT WAVE INTO THE AREA QUICKLY BEHIND THE FIRST
THURSDAY NIGHT. THIS WAVE WILL DIG FURTHER SOUTH AND BRING BETTER
FORCING AND MOISTURE INTO THE FORECAST AREA...AS CURRENTLY REFLECTED
IN GRIDS WITH LOW TO HIGH CHANCE POPS FROM EAST TO WEST ACROSS THE
CWA. STILL LIKE THE NOTION OF A SMALL WINDOW OF DRY WX BETWEEN THESE
TWO SYSTEMS SO WILL STAY WITH DRY FCST 00-06Z FRI. WITH RELATIVELY
WARMER AIR IN PLACE...WILL TREND WX GRIDS TOWARD LIQUID PRECIP WITH
ALL RAIN IN THE SOUTHERN TIER BUT STAY WITH MIX ELSEWHERE GIVEN
NOCTURNAL TIMING. ABOVE NORMAL TEMPS THROUGH THE PERIOD AND GUIDANCE
REASONABLE IN HANDLING THIS.
&&
.LONG TERM...
FRIDAY THROUGH WEDNESDAY
AN UPPER LEVEL DISTURBANCE WILL TRACK SOUTHEASTWARD FROM SOUTHERN
ALBERTA/SASKATCHEWAN THURSDAY MORNING INTO THE MIDWEST BY FRIDAY
MORNING. MEDIUM RANGE MODELS ARE IN DECENT AGREEMENT WITH THE TRACK
OF THE WAVE AND THE ATTENDANT SURFACE LOW...HOWEVER MINOR TIMING
DIFFERENCES EXIST. WENT AHEAD AND BUMPED POPS UP TO LIKELY ACROSS
THE NORTHERN HALF OF THE CWA FRIDAY MORNING...ALONG THE PREFERRED
TRACK OF THE SURFACE LOW. PRECIPITATION TYPE CONCERNS REMAIN AN
ISSUE WITH THIS SYSTEM. THERMAL PROFILES PER MODELS SOUNDINGS
SUGGEST MOSTLY RAIN WITH THIS SYSTEM THROUGH THE DAY FRIDAY...WITH
COLDER AIR ARRIVING LATE AFTERNOON...INTRODUCING A MIX AND EVENTUAL
CHANGEOVER TO SNOW AND PRECIPITATION TAPERS OFF. HOWEVER...GIVEN THE
TIMING DIFFERENCES BETWEEN MODELS....AND SLIGHT MODEL DIFFERENCES
WITH THE TRACK OF THE SYSTEM...PREFERRED TO LEAVE A RAIN/SNOW
MENTION FOR FRIDAY ACROSS THE NORTH AND FRIDAY NIGHT EVERYWHERE.
WILL DEFER REFINING OF P-TYPE TO NEXT FORECAST CYCLE AND HOPEFULLY
MORE CONSISTENT MODEL SOLUTIONS. NO MAJOR CHANGES TO TEMPERATURES
FRIDAY AND FRIDAY NIGHT.
SYSTEM EXITS THE REGION BY SATURDAY MORNING...AND HIGH PRESSURE
BUILDS INTO THE REGION FROM THE SOUTHWEST. CONDITIONS WILL BE DRY
THROUGH THE DAY SATURDAY...BEFORE A SIGNIFICANT PATTERN CHANGE
ARRIVES ACROSS THE REGION.
UPPER LEVEL TROF WILL DIG SOUTHEAST FROM CANADA INTO THE EASTERN
CONUS SUNDAY INTO EARLY NEXT WEEK...AND ALONG WITH IT A POLAR AIR
MASS...WITH MODEL H85 TEMPS APPROACHING -20C BY TUESDAY ACROSS THE
REGION. SFC LOW PRESSURE WILL MOVE ACROSS THE NORTHERN TIER INTO THE
GREAT LAKES REGION BY BY SUNDAY. MODELS DIFFER WITH THE EXACT TRACK
OF THE LOW...WITH THE GFS SUPPORTING A FASTER MORE SOUTHERLY
TRACK...AND THE ECMWF A BIT SLOWER WITH A MORE NORTHERLY TRACK.
CONSEQUENTLY...THE GFS SUPPORTS STRONGER FORCING ACROSS THE REGION
SATURDAY NIGHT INTO SUNDAY...WHILE THE ECMWF SUPPORTS WEAKER FORCING
MOVING INTO THE AREA DURING THE DAY SUNDAY. ALLBLEND PROCEDURE
INTRODUCED SLIGHT CHANCE POPS ON SATURDAY NIGHT...WHICH HAVE BEEN
RETAINED FOR COLLABORATIVE PURPOSES. FEEL THAT THE GFS IS SLIGHTLY
TO FAST WITH THE TRACK OF THE SYSTEM AND BEST PRECIP CHANCES WILL BE
DURING THE DAY SUNDAY.
COLD AIR WILL THEN FILTER INTO THE REGION BEHIND THE FRONT...WHICH
WILL BE THE CATALYST FOR LAKE EFFECT SNOW LATE SUNDAY THROUGH
TUESDAY ACROSS THE AREA. MODELS ARE IN DECENT AGREEMENT OF A NW TO
NORTHERLY FETCH AND ADEQUATE MOISTURE PROFILE...WITH LAKE SFC TO H85
DELTA TS IN EXCESS OF 20C...AND LAKE SFC TO H7 DELTA TS IN THE MID
TO UPPER 20C RANGE. WENT AHEAD AND RAISED POPS SUNDAY NIGHT INTO
TUESDAY TO HIGH CHANCE ACROSS LAKE EFFECT PREFERRED AREAS. NO MAJOR
CHANGES TO TEMPERATURES...AS THE ALLBLEND SOLUTIONS HAVE CAUGHT ON
TO COLDER TEMPERATURES WITH THE ARRIVAL OF THE POLAR AIR MASS.&&
.AVIATION... / 18Z TAFS /
LATEST OBS INDICATING THAT MVFR LAKE EFFECT CLOUDS STILL IMPACTING
KSBN. DIFFICULT TO DETERMINE TRENDS FROM VIS SAT GIVEN MID LEVEL
DECK ON TOP...BUT WILL EXTEND A TEMPO MVFR FOR FIRST HOUR OF THIS
CYCLE AT KSBN THEN BELIEVE WINDS BACKING TO MORE SW LATER THIS
AFTERNOON SHOULD SHIFT LAKE EFFECT CLOUDS TO THE NORTH AND EAST.
WEAK CLIPPER SYSTEM MOVING DOWN TONIGHT WILL KEEP MVFR DECK IN PLACE
OVER BOTH SITES AND ALSO CONTINUE BACKING OF WINDS TO MORE SOUTHERLY
AND INCREASE TO 10-15KTS TOWARD THE END OF THE PERIOD. UNCERTAINTY
OF PRECIP DEVELOPMENT WITH THIS SYSTEM WILL PRECLUDE ANY MENTION FOR
THIS TAF CYCLE.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SHORT TERM...LOGSDON
LONG TERM...NG
AVIATION...LOGSDON
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
513 PM CST THU DEC 29 2011
.AVIATION...
FOR THE 00Z TAF ISSUANCE...
21Z RUN SUGGESTING THAT A FEW SPRINKLES OR EVEN A BRIEF SHOWER
WILL BE POSSIBLE NEAR THE HAYS AREA THROUGH 02Z BASED ON LOCATION
OF THE UPPER LEVEL JET AND INCREASING MID LEVEL INSTABILITY AHEAD
OF AN UPPER LEVEL TROUGH. FURTHER SOUTH THE LATEST 21Z RUC AND 18Z
NAM SOUNDINGS CONTINUE TO SUPPORT ONLY MID-HIGH LEVEL MOISTURE
CROSSING THIS REGION. AS A RESULT WILL BRIEFLY MENTION A VCSH IN
THE TAFS FOR A COUPLE OF HOURS AT HAYS WHILE LEAVING THE FORECAST
DRY FURTHER SOUTH WITH VFR CIGS THROUGH THE FIRST HALF OF THE
NIGHT. AS THIS UPPER TROUGH PASSES...A COLD FRONT WILL MOVE SOUTH
ACROSS NORTH CENTRAL AND SOUTHWEST KANSAS. 22Z SURFACE
OBSERVATIONS INDICATING THAT THE FRONT WAS BEGINNING TO MOVE INTO
NORTHWEST KANSAS WHICH WAS QUICKER THAN WHAT THE 18Z NAM MODEL
SUGGESTED. 19Z HRRR AND 21Z RUC40 WERE CLOSER TO THE 22Z FRONTAL
LOCATION SO WILL LEAN TOWARDS THE FASTER HRRR/RUC ON TIMING OF THE
FROPA EARLY TONIGHT. WILL ALSO FAVOR THE STRONGER WINDS THE HRRR
INDICATED BEHIND THIS FRONT BASED ON WIND SPEEDS CURRENTLY
OCCURRING BEHIND THIS FRONT ACROSS EASTERN CO AND FAR SOUTHWEST
NEBRASKA AND SURFACE PRESSURE TENDENCIES. WINDS WILL BEGIN TO
SUBSIDE AFTER 03Z AS THE COLD FRONT QUICKLY MOVES INTO CENTRAL
KANSAS AND NORTHWEST OKLAHOMA. WIND SPEEDS ARE EXPECTED TO FALL
BACK INTO AROUND 10KTS AFTER MIDNIGHT. -RB
&&
.PREV DISCUSSION... /ISSUED 301 PM CST THU DEC 29 2011/
DISCUSSION...
DAYS 1-2...
THE MAIN FORECAST CHALLENGES ARE TEMPERATURES ESPECIALLY IN SNOWPACK
AREAS, AND WINDS AND TEMPS ON SATURDAY WITH A COLD FRONT.
TWO STRONG UPPER LEVEL SHORTWAVE TROUGHS WILL PASS THROUGH THE
PLAINS IN NORTHWESTERLY FLOW ALOFT THROUGH FRIDAY WITH ONLY SOME
HIGH TO MID LEVEL CLOUDS AT TIMES. NO PRECIPITATION IS EXPECTED.
THE FIRST WAVE TONIGHT WILL SWITCH WEST TO SOUTHWEST WINDS TO THE
NORTHWEST AT 10 TO 20 MPH OVERNIGHT WITH LOWS FROM THE MID 20S
NORTHWEST TO LOW TO MID 30S ELSEWHERE. EXPECT HIGHS ON FRIDAY IN THE
40S IN SNOWPACK AREAS AND MID TO UPPER 50S ELSEWHERE.
THE 2ND WAVE WILL BE STRONGER AND A LITTLE MORE SOUTH AND WILL MOVE
INTO THE CENTRAL PLAINS ON SATURDAY AFTERNOON WITH A STRONG COLD
FRONT. HOWEVER ON SATURDAY MORNING A STRONG LOW LEVEL INVERSION WILL
BE IN PLACE. THE COLD FRONT WILL THEN MOVE ACROSS WESTERN KANSAS IN
THE AFTERNOON PUSHING THE WARM AIR JUST ABOVE THE GROUND TO THE
SURFACE. THIS SHOULD INITIALLY CAUSE A DRAMATIC WARM UP AT THE
GROUND FOR A FEW HOURS BEFORE THE COLD AIR ADVECTION CATCHES UP.
HIGHS COULD REACH THE MID TO UPPER 50S NORTH TO MID 60S SOUTH. THEN
TEMPERATURES COULD FALL IN THE MID TO LATE AFTERNOON WITH GOOD COLD
AIR ADVECTION BEHIND THE COLD FRONT. STRONG WINDS OF 25 TO 35 MPH
ARE ALSO ANTICIPATED WITH THE COLD FRONT AND WE COULD BE CLOSE OR
ABOVE WIND ADVISORY CRITERIA.
DAYS 3-7...
MEDIUM RANGE MODELS INDICATE AN UPPER LEVEL TROUGH OF LOW PRESSURE
TRACKING EAST-SOUTHEAST ACROSS THE CENTRAL PLAINS SATURDAY EVENING
THEN MOVING ACROSS THE GREAT LAKES REGION SUNDAY. AN ATTENDANT COLD
FRONT IS PROGGED TO PUSH SOUTHEAST ACROSS WESTERN KANSAS SOMETIME BY
SATURDAY EVENING. HOWEVER, WHAT LITTLE PRECIP DOES FALL IS EXPECTED
TO REMAIN JUST OFF TO OUR NORTH WITH THE STRENGTH OF THE UPPER LEVEL
SYSTEM. A REAL LACK OF LOW LEVEL MOISTURE WILL ALSO HURT ANY PRECIP
CHANCES IN WESTERN KANSAS. FAIRLY DRY CONDITIONS ARE EXPECTED TO
CONTINUE THROUGH THE MIDDLE OF THE WEEK AS UPPER LEVEL RIDGING
DEVELOPS ACROSS THE INTERMOUNTAIN WEST AND BEGINS TO EDGE EASTWARD.
TEMPERATURES ARE EXPECTED TO BE MUCH COOLER SUNDAY IN WAKE OF THE
COLD FRONTAL PASSAGE FORECAST TO PUSH THROUGH WESTERN KANSAS BY
SATURDAY NIGHT. COLDER AIR...WITH H85 TEMPERATURES DOWN AROUND 3C
BELOW TO 5C BELOW...WILL SPILL SOUTH INTO WESTERN KANSAS THROUGH
THE DAY SUNDAY. LOOK FOR WIDESPREAD 40S(F) WITH UPPER 30S(F)
POSSIBLE IN WEST CENTRAL KANSAS. THE COOLER TEMPERATURES. A
SLIGHT AND GRADUAL WARMING TREND IS THEN EXPECTED TO TAKE PLACE
EARLY NEXT WEEK AS UPPER LEVEL RIDGING DEVELOPS ACROSS THE
INTERMOUNTAIN WEST AND BEGINS TO EDGE TOWARD THE WESTERN HIGH
PLAINS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 29 54 31 59 / 0 0 0 0
GCK 25 45 30 58 / 0 0 0 0
EHA 29 50 32 60 / 0 0 0 0
LBL 27 51 31 61 / 0 0 0 0
HYS 30 47 30 57 / 0 0 0 0
P28 33 58 34 65 / 0 0 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1019 AM MST WED DEC 28 2011
.SYNOPSIS...
222 AM MST WED DEC 28 2011
LATEST SATELLITE IMAGERY AND RUC ANALYSIS SHOW AN UPPER LEVEL RIDGE
OVER THE WEST COAST...WITH AREAS OF CLOUDS AND PRECIPITATION MOVING
ALONG THE NORTHERN PERIPHERY. OVER THE HIGH PLAINS A SHORT WAVE
TROUGH WAS PROGRESSING SOUTHEAST INTO TEXAS. AT THE SURFACE A
TROUGH WAS MOVING THROUGH THE TRI-STATE AREA WITH SOUTHWEST WINDS
TURNING TO THE NORTHWEST BEHIND THE TROUGH.
JTL
&&
.SHORT TERM (TODAY-FRIDAY)...
222 AM MST WED DEC 28 2011
ABOVE NORMAL TEMPERATURES WILL BE THE FOCUS FOR THIS PERIOD.
TODAY...NORTHWEST FLOW WILL CONTINUE OVER THE AREA WITH A MINOR
SHORT WAVE TROUGH MOVING THROUGH THE FLOW DURING THE DAY. WITH THE
RIGHT EXIT REGION OF THE JET MOVING IN AND SOME MOISTURE MOVING
THROUGH THE FLOW...AM NOT ANTICIPATING ANYTHING MORE THAN SOME
CLOUDS. WINDS WILL BE BREEZY TODAY AS SOME OF THE STRONGER WINDS
ABOVE THE SURFACE ACCOMPANYING THE TROUGH ARE ABLE TO MIX DOWN.
TEMPERATURES WILL BE WARMER THAN YESTERDAY AS 850MB TEMPERATURES
WARM BEHIND THE TROUGH.
THURSDAY AND FRIDAY...A COUPLE OF SHORT WAVE TROUGHS WILL MOVE
THROUGH THE NORTHWEST FLOW...PLACING THE RIGHT ENTRANCE AND LEFT
EXIT REGIONS OF THE JET OVER THE TRI-STATE AREA. SOME 700-300MB
FRONTOGENESIS WILL MOVE OVER THE AREA WITH THESE TROUGHS. MODELS
DISAGREE WITH HOW MUCH MOISTURE IS PRESENT AS THE TROUGHS MOVE
THROUGH...ESPECIALLY FOR THE TROUGH COMING THROUGH FRIDAY MORNING.
SREF PRECIPITATION PROBABILITIES ARE ZERO WHILE THE GEFS DOES SHOW
A SMALL CHANCE FOR SOME MINIMAL PRECIPITATION IN THE
BENKELMAN...MCCOOK AND OBERLIN AREA. WITH SUCH DISAGREEMENT AMONG
MODELS...WILL LEAVE FORECAST DRY FOR NOW.
WINDS WILL STRENGTHEN THURSDAY AS STRONG UPPER LEVEL WINDS
ACCOMPANY THE TROUGH THROUGH THE AREA AND ARE ABLE TO MIX TO THE
SURFACE. CURRENTLY LOOKS LIKE AREAS NORTH OF HIGHWAY 36 WILL HAVE
THE BEST MIXING AND STRONGEST WINDS...WITH GUSTS UP TO 35 MPH
POSSIBLE. THE WINDS WILL DECREASE AT SUNSET. FRIDAY WINDS WILL BE
LIGHT AS A SURFACE HIGH PRESSURE MOVES INTO THE AREA AHEAD OF A
DEVELOPING SURFACE TROUGH OVER COLORADO.
TEMPERATURE-WISE THURSDAY WILL BE THE WARMEST...WITH HIGHS
REACHING THE LOWER 60S THANKS TO 850MB TEMPERATURES WARMING AS THE
TROUGH MOVES THROUGH. FRIDAY TEMPERATURES WILL BE A FEW DEGREES
COOLER AS COOLER AIR BEHIND THE TROUGH FROM FRIDAY MORNING MOVES
INTO THE AREA.
JTL
.LONG TERM (SATURDAY-TUESDAY)...
222 AM MST WED DEC 28 2011
NEW ECMWF IS MORE IN LINE WITH THE GFS SATURDAY BRINGING A
SHORTWAVE TROUGH AND COLD FRONT THROUGH THE FORECAST AREA.
DEPENDING ON THE TIMING OF THE FRONT...TEMPERATURES MAY WARM
NICELY IN THE MORNING. CURRENT PROJECTIONS OF FRONTAL PASSAGE IN
THE AFTERNOON...THOUGH...WILL LIMIT TOO MUCH WARMING...AND WILL
CONTINUE WITH HIGH TEMPERATURES IN THE LOWER TO MID 50S. ECMWF
CONTINUES TO DEPICT LIGHT PRECIPITATION SATURDAY NIGHT OVER THE
NORTHERN SECTION OF AREA...BUT AGREE WITH OTHER MODELS ABOUT THE
LIMITED AMOUNT OF MOISTURE SO WILL CONTINUE WITH A DRY FORECAST.
STRONG 500 MB RIDGE WILL THEN BUILD OVER THE WESTERN UNITED
STATES BEGINNING SUNDAY AND CONTINUING THROUGH THE EARLY PART OF
NEXT WEEK. THE QUESTION WILL BE HOW FAR EAST THE RIDGE AXIS MOVES
AND HOW STRONG THE HEIGHT RISES WILL BE. THE ECMWF IS SLIGHTLY
STRONGER WITH THE RIDGE AXIS...BUT ALSO FURTHER WEST OF THE GFS.
THIS PLACES STRONG NORTH TRAJECTORIES OVER THE AREA MONDAY FOR
SOME COLD AIR ADVECTION. THE GFS IS FURTHER EAST AND WOULD SUPPORT
WARMER TEMPERATURES. REGARDLESS...BOTH MODELS PROG 500 MB HEIGHTS
OVER 576 METERS BY TUESDAY FOR ABOVE NORMAL TEMPERATURES AND
CONTINUED DRY.
&&
.AVIATION...
1019 AM MST WED DEC 28 2011
FOR THE 18Z TAFS...VFR CONDITIONS WILL PREVAIL THROUGH THE PERIOD.
WINDS WILL BE WESTERLY...AND SIMILAR TO YESTERDAY...KGLD WILL SEE
AFTERNOON GUSTS NEARING 20 KNOTS. HIGH CLOUDS WILL MOVE OVER THE
TERMINALS THROUGHOUT THE AFTERNOON. ANY REMAINING GUSTS WILL
SUBSIDE NEAR 00Z AS DAYTIME MIXING ENDS.
CJS
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
NE...NONE.
CO...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GOODLAND KS
404 AM MST WED DEC 28 2011
.SYNOPSIS...
222 AM MST WED DEC 28 2011
LATEST SATELLITE IMAGERY AND RUC ANALYSIS SHOW AN UPPER LEVEL RIDGE
OVER THE WEST COAST...WITH AREAS OF CLOUDS AND PRECIPITATION MOVING
ALONG THE NORTHERN PERIPHERY. OVER THE HIGH PLAINS A SHORT WAVE
TROUGH WAS PROGRESSING SOUTHEAST INTO TEXAS. AT THE SURFACE A
TROUGH WAS MOVING THROUGH THE TRI-STATE AREA WITH SOUTHWEST WINDS
TURNING TO THE NORTHWEST BEHIND THE TROUGH.
JTL
&&
.SHORT TERM (TODAY-FRIDAY)...
222 AM MST WED DEC 28 2011
ABOVE NORMAL TEMPERATURES WILL BE THE FOCUS FOR THIS PERIOD.
TODAY...NORTHWEST FLOW WILL CONTINUE OVER THE AREA WITH A MINOR
SHORT WAVE TROUGH MOVING THROUGH THE FLOW DURING THE DAY. WITH THE
RIGHT EXIT REGION OF THE JET MOVING IN AND SOME MOISTURE MOVING
THROUGH THE FLOW...AM NOT ANTICIPATING ANYTHING MORE THAN SOME
CLOUDS. WINDS WILL BE BREEZY TODAY AS SOME OF THE STRONGER WINDS
ABOVE THE SURFACE ACCOMPANYING THE TROUGH ARE ABLE TO MIX DOWN.
TEMPERATURES WILL BE WARMER THAN YESTERDAY AS 850MB TEMPERATURES
WARM BEHIND THE TROUGH.
THURSDAY AND FRIDAY...A COUPLE OF SHORT WAVE TROUGHS WILL MOVE
THROUGH THE NORTHWEST FLOW...PLACING THE RIGHT ENTRANCE AND LEFT
EXIT REGIONS OF THE JET OVER THE TRI-STATE AREA. SOME 700-300MB
FRONTOGENESIS WILL MOVE OVER THE AREA WITH THESE TROUGHS. MODELS
DISAGREE WITH HOW MUCH MOISTURE IS PRESENT AS THE TROUGHS MOVE
THROUGH...ESPECIALLY FOR THE TROUGH COMING THROUGH FRIDAY MORNING.
SREF PRECIPITATION PROBABILITIES ARE ZERO WHILE THE GEFS DOES SHOW
A SMALL CHANCE FOR SOME MINIMAL PRECIPITATION IN THE
BENKELMAN...MCCOOK AND OBERLIN AREA. WITH SUCH DISAGREEMENT AMONG
MODELS...WILL LEAVE FORECAST DRY FOR NOW.
WINDS WILL STRENGTHEN THURSDAY AS STRONG UPPER LEVEL WINDS
ACCOMPANY THE TROUGH THROUGH THE AREA AND ARE ABLE TO MIX TO THE
SURFACE. CURRENTLY LOOKS LIKE AREAS NORTH OF HIGHWAY 36 WILL HAVE
THE BEST MIXING AND STRONGEST WINDS...WITH GUSTS UP TO 35 MPH
POSSIBLE. THE WINDS WILL DECREASE AT SUNSET. FRIDAY WINDS WILL BE
LIGHT AS A SURFACE HIGH PRESSURE MOVES INTO THE AREA AHEAD OF A
DEVELOPING SURFACE TROUGH OVER COLORADO.
TEMPERATURE-WISE THURSDAY WILL BE THE WARMEST...WITH HIGHS
REACHING THE LOWER 60S THANKS TO 850MB TEMPERATURES WARMING AS THE
TROUGH MOVES THROUGH. FRIDAY TEMPERATURES WILL BE A FEW DEGREES
COOLER AS COOLER AIR BEHIND THE TROUGH FROM FRIDAY MORNING MOVES
INTO THE AREA.
JTL
.LONG TERM (SATURDAY-TUESDAY)...
222 AM MST WED DEC 28 2011
NEW ECMWF IS MORE IN LINE WITH THE GFS SATURDAY BRINGING A
SHORTWAVE TROUGH AND COLD FRONT THROUGH THE FORECAST AREA.
DEPENDING ON THE TIMING OF THE FRONT...TEMPERATURES MAY WARM
NICELY IN THE MORNING. CURRENT PROJECTIONS OF FRONTAL PASSAGE IN
THE AFTERNOON...THOUGH...WILL LIMIT TOO MUCH WARMING...AND WILL
CONTINUE WITH HIGH TEMPERATURES IN THE LOWER TO MID 50S. ECMWF
CONTINUES TO DEPICT LIGHT PRECIPITATION SATURDAY NIGHT OVER THE
NORTHERN SECTION OF AREA...BUT AGREE WITH OTHER MODELS ABOUT THE
LIMITED AMOUNT OF MOISTURE SO WILL CONTINUE WITH A DRY FORECAST.
STRONG 500 MB RIDGE WILL THEN BUILD OVER THE WESTERN UNITED
STATES BEGINNING SUNDAY AND CONTINUING THROUGH THE EARLY PART OF
NEXT WEEK. THE QUESTION WILL BE HOW FAR EAST THE RIDGE AXIS MOVES
AND HOW STRONG THE HEIGHT RISES WILL BE. THE ECMWF IS SLIGHTLY
STRONGER WITH THE RIDGE AXIS...BUT ALSO FURTHER WEST OF THE GFS.
THIS PLACES STRONG NORTH TRAJECTORIES OVER THE AREA MONDAY FOR
SOME COLD AIR ADVECTION. THE GFS IS FURTHER EAST AND WOULD SUPPORT
WARMER TEMPERATURES. REGARDLESS...BOTH MODELS PROG 500 MB HEIGHTS
OVER 576 METERS BY TUESDAY FOR ABOVE NORMAL TEMPERATURES AND
CONTINUED DRY.
&&
.AVIATION...
404 AM MST WED DEC 28 2011
FOR THE 12Z TAFS...VFR CONDITIONS WILL CONTINUE AT KGLD/KMCK THE
NEXT 24 HOURS. SURFACE WINDS WILL GENERALLY BE 5-15 KNOTS...THOUGH
A FEW HIGHER GUSTS MAY OCCUR AT KGLD FROM 19Z-23Z.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
NE...NONE.
CO...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GOODLAND KS
238 AM MST WED DEC 28 2011
.SYNOPSIS...
222 AM MST WED DEC 28 2011
LATEST SATELLITE IMAGERY AND RUC ANALYSIS SHOW AN UPPER LEVEL RIDGE
OVER THE WEST COAST...WITH AREAS OF CLOUDS AND PRECIPITATION MOVING
ALONG THE NORTHERN PERIPHERY. OVER THE HIGH PLAINS A SHORT WAVE
TROUGH WAS PROGRESSING SOUTHEAST INTO TEXAS. AT THE SURFACE A
TROUGH WAS MOVING THROUGH THE TRI-STATE AREA WITH SOUTHWEST WINDS
TURNING TO THE NORTHWEST BEHIND THE TROUGH.
JTL
&&
.SHORT TERM (TODAY-FRIDAY)...
222 AM MST WED DEC 28 2011
ABOVE NORMAL TEMPERATURES WILL BE THE FOCUS FOR THIS PERIOD.
TODAY...NORTHWEST FLOW WILL CONTINUE OVER THE AREA WITH A MINOR
SHORT WAVE TROUGH MOVING THROUGH THE FLOW DURING THE DAY. WITH THE
RIGHT EXIT REGION OF THE JET MOVING IN AND SOME MOISTURE MOVING
THROUGH THE FLOW...AM NOT ANTICIPATING ANYTHING MORE THAN SOME
CLOUDS. WINDS WILL BE BREEZY TODAY AS SOME OF THE STRONGER WINDS
ABOVE THE SURFACE ACCOMPANYING THE TROUGH ARE ABLE TO MIX DOWN.
TEMPERATURES WILL BE WARMER THAN YESTERDAY AS 850MB TEMPERATURES
WARM BEHIND THE TROUGH.
THURSDAY AND FRIDAY...A COUPLE OF SHORT WAVE TROUGHS WILL MOVE
THROUGH THE NORTHWEST FLOW...PLACING THE RIGHT ENTRANCE AND LEFT
EXIT REGIONS OF THE JET OVER THE TRI-STATE AREA. SOME 700-300MB
FRONTOGENESIS WILL MOVE OVER THE AREA WITH THESE TROUGHS. MODELS
DISAGREE WITH HOW MUCH MOISTURE IS PRESENT AS THE TROUGHS MOVE
THROUGH...ESPECIALLY FOR THE TROUGH COMING THROUGH FRIDAY MORNING.
SREF PRECIPITATION PROBABILITIES ARE ZERO WHILE THE GEFS DOES SHOW
A SMALL CHANCE FOR SOME MINIMAL PRECIPITATION IN THE
BENKLEMEN...MCCOOK AND OBERLIN AREA. WITH SUCH DISAGREEMENT AMONG
MODELS...WILL LEAVE FORECAST DRY FOR NOW.
WINDS WILL STRENGTHEN THURSDAY AS STRONG UPPER LEVEL WINDS
ACCOMPANY THE TROUGH THROUGH THE AREA AND ARE ABLE TO MIX TO THE
SURFACE. CURRENTLY LOOKS LIKE AREAS NORTH OF HIGHWAY 36 WILL HAVE
THE BEST MIXING AND STRONGEST WINDS...WITH GUSTS UP TO 35 MPH
POSSIBLE. THE WINDS WILL DECREASE AT SUNSET. FRIDAY WINDS WILL BE
LIGHT AS A SURFACE HIGH PRESSURE MOVES INTO THE AREA AHEAD OF A
DEVELOPING SURFACE TROUGH OVER COLORADO.
TEMPERATURE-WISE THURSDAY WILL BE THE WARMEST...WITH HIGHS
REACHING THE LOWER 60S THANKS TO 850MB TEMPERATURES WARMING AS THE
TROUGH MOVES THROUGH. FRIDAY TEMPERATURES WILL BE A FEW DEGREES
COOLER AS COOLER AIR BEHIND THE TROUGH FROM FRIDAY MORNING MOVES
INTO THE AREA.
JTL
.LONG TERM (SATURDAY-TUESDAY)...
222 AM MST WED DEC 28 2011
NEW ECMWF IS MORE IN LINE WITH THE GFS SATURDAY BRINGING A
SHORTWAVE TROUGH AND COLD FRONT THROUGH THE FORECAST AREA.
DEPENDING ON THE TIMING OF THE FRONT...TEMPERATURES MAY WARM
NICELY IN THE MORNING. CURRENT PROJECTIONS OF FRONTAL PASSAGE IN
THE AFTERNOON...THOUGH...WILL LIMIT TOO MUCH WARMING...AND WILL
CONTINUE WITH HIGH TEMPERATURES IN THE LOWER TO MID 50S. ECMWF
CONTINUES TO DEPICT LIGHT PRECIPITATION SATURDAY NIGHT OVER THE
NORTHERN SECTION OF AREA...BUT AGREE WITH OTHER MODELS ABOUT THE
LIMITED AMOUNT OF MOISTURE SO WILL CONTINUE WITH A DRY FORECAST.
STRONG 500 MB RIDGE WILL THEN BUILD OVER THE WESTERN UNITED
STATES BEGINNING SUNDAY AND CONTINUING THROUGH THE EARLY PART OF
NEXT WEEK. THE QUESTION WILL BE HOW FAR EAST THE RIDGE AXIS MOVES
AND HOW STRONG THE HEIGHT RISES WILL BE. THE ECMWF IS SLIGHTLY
STRONGER WITH THE RIDGE AXIS...BUT ALSO FURTHER WEST OF THE GFS.
THIS PLACES STRONG NORTH TRAJECTORIES OVER THE AREA MONDAY FOR
SOME COLD AIR ADVECTION. THE GFS IS FURTHER EAST AND WOULD SUPPORT
WARMER TEMPERATURES. REGARDLESS...BOTH MODELS PROG 500 MB HEIGHTS
OVER 576 METERS BY TUESDAY FOR ABOVE NORMAL TEMPERATURES AND
CONTINUED DRY.
&&
.AVIATION...
942 PM MST TUE DEC 27 2011
VFR CONDS WILL PREVAIL AT BOTH TERMINALS THROUGH THE NEXT 24 HOURS.
NORTHWESTERLY WINDS TO BEGIN THE PERIOD WILL SLOWLY SWITCH TO THE
WEST AND SOUTHWEST BY WEDNESDAY AFTERNOON. MID/HIGH CLOUDS WILL BE ABUNDANT
AS UPPER LEVEL DISTURBANCES MOVE OVER THE REGION.
BAS
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
NE...NONE.
CO...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
1211 AM EST WED DEC 28 2011
...Updated Aviation Discussion...
.Forecast Update...
Snowfall earlier today occurred across all of the South Indiana
counties, with most counties in north central Kentucky also seeing
traces. The only accumulations noted in our forecast area were in
Dubois, Orange, Crawford, and Washington counties, where at most a
half inch accumulated on grassy and elevated surfaces. That snow
now has melted.
The expected follow-up precipitation has taken a little longer than
expected to develop, much later than the HRRR indicated but in line
with the 12Z SPC WRF. The latter model pointed more to the upslope
causing snows over the eastern forecast area, and latest 88D is now
showing some indication that a drizzle/flurry mix is developing in
this region. Based on dry air driving its way into the region, this
precipitation will not last more than a few more hours.
Likely will continue to issue the special weather statement about
some slick spots on area roads overnight. Winds this afternoon and
evening have done a good job of drying out area roadways according
to road webcams. Still expect a few patches to have been wind
protected, and with temperatures falling into the upper 20s, these
patches should freeze over.
&&
.Short Term (This Evening - Wednesday)...
Precipitation has all but ended across the CWA with barely
measurable rain or light snow moving east of I 65 and into the
Bluegrass. Several calls were made to southern Indiana and west
central Kentucky counties late this morning/early this afternoon
with most locations only picking up traces of snowfall. The most
noticeable accumulations were in Dubois county where up to a half
inch accumulated on grassy surfaces and cars.
Also of note, the all time precipitation record for a year was
broken at Lexington today. As of 7 AM EST this morning, total
rainfall for the year at Lexington was 65.86 inches which surpassed
the old record of 65.76 inches set back in 1935. Additional rainfall
amounts of around a half an inch fell after 7 AM and will be tallied
after precipitation ends later this evening.
Surface low has moved off to the northeast and is on its way to the
eastern Great Lakes this evening. Surface winds will continue to be
strong as pressure gradient is tight behind the deepening low. Look
for west northwest winds between 10 and 20 mph, gusting as high as
30 mph through about 7 PM EST. Thereafter, winds will gradually
slacken to the 5 to 15 mph range overnight.
Looking upstream across west central Indiana and southern Illinois,
temperatures have warmed back into the upper 30s and lower 40s. Raw
Nam surface temperatures had this depicted well so have used them
for the temperature trend through this evening. Temperatures will
remain steady or warm slightly to the upper 30s before gradually
falling after midnight to the upper 20s and around 30 degrees. Will
have to watch a secondary surge of low level moisture streaming into
the area from the northwest as this could produce flurries or a
light snow shower with west northwest flow aiding in some upslope
lift. Also, a look at forecast soundings actually shows some
convective instability in the lowest levels, although saturation
only makes it to about -8 C before low level moisture is cut off.
Given the fact that ice crystals may be hard to come by and low
level moisture is shallow, will only include flurries along and west
of I 65 late this afternoon and this evening. Best chance for a
light snow shower will be in the Bluegrass. Will let SPS that had
voiced concern about scattered moderate snow showers and re-freezing
of roadways overnight expire at 5 PM EST.
Otherwise, precipitation threat exits the Bluegrass region shortly
after midnight with dry weather and mostly clear to partly cloudy
skies through Wednesday. The west northwest wind will continue on
Wednesday and only allow highs to get into the upper 30s to around
40 degrees.
.Long Term (Wednesday Night - Tuesday)...
The first weather system of interest in the long term period is a
clipper system diving down from the NW for Thurs night/Fri. This
system should bring light rain to portions of southern Indiana and
north central KY including the Bluegrass. Ahead of this system,
temperatures will warm into the upper 40s and lower 50s for highs on
Thurs. Lows should range from the upper 20s/lower 30s Wed night to
upper 30s/lower 40s for Thurs night.
We`ll see a brief break in weather systems Friday Night/Saturday
before the pattern reloads. There is very low confidence in the
weekend weather system. The 12Z ECMWF overly deepens a significant
trough over the Plains states by early next week while the 12Z GFS
depicts a much shallower progressive trough. Think that the real
soln is some where in the middle so tried to reflect that in the
grids. Will keep low 20-30% POPs Sat night-Sun night until a
reasonable consensus can be reached. Seems like the 12Z GFS trended
deeper with its trough, however, the 12Z ECMWF looks like it fell
off the deep end with digging such a deep trough over the CONUS.
The degree of troughing will determine temperatures and weather
type. Right now will put highs in the 50s ahead of it and 30s and
40s behind it.
&&
.Aviation (06Z TAF Issuance)...
Back edge of clouds associated with an exiting upper trough/lake
effect enhancement will soon move across the terminals and SDF and
LEX will improve to VFR (BWG will remain VFR). Through the next few
hours though, roughly by 09z, CIGs at SDF/LEX will be in the MVFR
range with even a small chance for very light snow/drizzle mix at
LEX. Gusty winds may occur, as well, over the next few hours.
By or shortly after 12z, high pressure will spread across the
region, helping to relax our gusty northwest winds as they back
around to the west-southwest. A weak upper level wave will bring in
mid-upper level clouds nearly as soon as the strato-cu deck exits
this morning. However, VFR conditions will be the rule from
mid-morning on.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
KY...NONE.
$$
Update...........RJS
Short Term.......BJS
Long Term........AMS
Aviation.........AL
AREA FORECAST DISCUSSION
NWS GRAY ME
1141 PM EST TUE DEC 27 2011
.SYNOPSIS...
LOW PRESSURE WILL MOVE NORTHEAST THROUGH EASTERN NEW YORK AND INTO
SOUTHERN QUEBEC OVERNIGHT. A STRONG NORTHWEST FLOW WILL SET UP
BEHIND THE DEPARTING LOW ON WEDNESDAY. WEAK HIGH PRESSURE WILL
BUILD IN FROM THE WEST ON THURSDAY. A WARM FRONT WILL APPROACH
FROM THE SOUTHWEST THURSDAY NIGHT AND STALL OVER THE REGION ON
FRIDAY AS SEVERAL WEAK AREAS OF LOW PRESSURE MOVE EAST ALONG IT.
THE LAST AREA OF LOW PRESSURE WILL CROSS SOUTHERN NEW ENGLAND ON
SATURDAY. A WEAK AREA OF HIGH PRESSURE WILL BUILD OVER THE AREA
SATURDAY NIGHT AND WILL SHIFT OFFSHORE ON SUNDAY AS A WARM FRONT
MOVES IN FROM THE SOUTHWEST. LOW PRESSURE WILL MOVE EAST THROUGH
NORTHERN NEW ENGLAND SUNDAY NIGHT AND INTO THE MARITIMES ON
MONDAY.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
UPDATE...MID LEVEL WARM AIR HAS NOW PUSHED TO THE CANADIAN BORDER...
AND THE SURFACE WARM FRONT HAS PUSHED INLAND ACROSS NORTHERN NEW
ENGLAND. STILL SOME AREAS IN THE FOOTHILLS THAT HAVE NOT SEEN THE
SWITCH TO SOUTHEAST WINDS AND DRAMATICALLY WARMING TEMPERATURES YET.
FRYEBURG... PLYMOUTH... AND LEBANON ARE STILL IN THE MID 30S WITH A
LIGHT NORTH WIND. NORTH OF THE MOUNTAINS... THE SOUTHEAST WINDS
ALOFT HAVE A DOWNSLOPING COMPONENT TO PUSH THE COLD SURFACE AIR OUT
SOONER... HELPING WHITEFIELD AND BERLIN CLIMB INTO THE 40S WITH A
GUSTY SOUTHEAST WIND. EXPECT RAIN FROM HERE ON OUT. DRY SLOT ALOFT
IS PUSHING ACROSS THE AREA... LEADING TO A MORE SHOWERY CONVECTIVE
NATURE TO THE RAIN. SURFACE TROUGH AXIS IS MOVING INTO VERMONT AND
MASSACHUSETTS... BRINGING AN END TO THE PRECIPITATION AS IT MOVES
THROUGH. HAVE UPDATED THE POPS AND TEMPERATURE GRIDS TO REFLECT
CURRENT THINKING REGARDING TIMING OF PRECIPITATION AND WARM AIR.
UPDATE...
TEMPERATURES ARE NOW TAKING OFF AND HAVE ADJUSTED THE GRIDS TO
REFLECT A NON-DIURNAL CURVE WITH THE MIN TEMPERATURE FIELD. THIS
RAPID WARMING IN THE COLUMN THIS EVENING HAS ALLOWED THE MIXED
PCPN TO SWITCH OVER TO MAINLY RAIN. THEREFORE...HAVE ALLOWED THE
FREEZING RAIN ADVISORIES TO EXPIRE. HAVE MENTIONED THIS CHANGEOVER
IN THE HWO AND CONTINUED THE POSSIBILITY OF "PATCHY" FREEZING RAIN
IN THE COLDEST OF THE VALLEYS IN THE MOUNTAINS/FOOTHILLS THROUGH
MIDNIGHT.
THE RAPID WARMING HAS ALSO ALLOWED FOR INCREASED MIXING AND HIGHER
WIND GUSTS THIS LAST HOUR. CONVECTIVE LOOKING RADAR IMAGERY TO OUR
SOUTH WILL QUICKLY MOVE NORTHWARD...BRINGING THE WIND GUSTS UP
SIGNIFICANTLY ALONG THE COAST AND THE HIGHER TERRAIN OVER THE NEXT
ONE TO TWO HOURS.
HAVE ALLOWED FOR THE ENDING OF THE WIND ADVISORIES AROUND 10Z. AT
THAT TIME...THE HRRR EXITS THE BEST PRESSURE GRADIENT OUT OF OUR
FORECAST AREA AND EAST OF PENOBSCOT BAY.
THE REST OF THE GRIDS WILL REMAIN RELATIVELY UNCHANGED. HAVE
NUDGED THE WAVE FORECAST UPWARDS BASED ON THE SWAN GFS
WHICH...DYNAMICALLY MAKES MORE SENSE AND ALSO ALLOWS US TO BE MORE
CONSISTENT WITH OUR CURRENT POSTED MWW.
PREV DISC...
SOME ADJUSTMENTS MADE TO THE GRIDS BASED ON CURRENTS CONDITIONS.
HAVE USED A NON-DIURNAL TEMPERATURE CURVE FOR OVERNIGHT LOWS.
ALSO...HAVE UPPED THE POPS FOR THE FIRST HALF OF THE NIGHT AS PCPN
SHIELD CONTINUES TO QUICKLY MOVE NORTH AND EAST ACROSS THE
FORECAST AREA...DESPITE INITIAL DRY CONDITIONS PER VERY DRY 12Z
GYX SOUNDING. THIS IS ALSO IN GOOD AGREEMENT WITH THE LATEST HRRR
UPDATE THIS HOUR.
THERE MAY CONTINUE TO BE AREAS OF -FZRA EARLY TONIGHT AS BOUNDARY
LAYER TEMPS CONTINUE TO HOVER AROUND FREEZING IN THE NORTHERN
SHELTERED VALLEYS. HAVE ISSUED A FREEZING RAIN ADVISORY UNTIL 10
PM FOR THIS REGION. HAVE ALSO ADDED A CHANCE FOR FREEZING RAIN IN
CENTRAL NH AND THE FOOTHILLS OF MAINE THROUGH THIS EVENING BASED
ON CURRENT AND SHORT TERM FORECAST CONDITIONS.
REST OF GRIDS WILL REMAIN UNCHANGED...HOWEVER...MAY NEED TO TWEAK
WIND GUST GRIDS TO BETTER MATCH CURRENT PRODUCTS.
&&
.SHORT TERM /WEDNESDAY NIGHT/...
COLDER AIR WILL MOVE BACK INTO THE REGION ON WEDNESDAY AS LOW
PRESSURE CONTINUES TO MOVE OFF TO THE NORTHEAST. EXPECT ANY
SHOWERS DOWNWIND OF THE MOUNTAINS TO END DURING THE MORNING HOURS.
IN THE NORTH WILL SEE RAIN SHOWERS CHANGING TO SNOW SHOWERS IN THE
MOUNTAINS WITH SOME MINOR ACCUMULATIONS POSSIBLE. EXPECT STEADY OR
SLOWLY FALLING TEMPERATURES DURING THE DAY WITH MOST AREAS DIPPING
TO THE FREEZING MARK BY LATE AFTERNOON. EXPECT NORTHWEST WINDS TO
INCREASE SIGNIFICANTLY DURING THE AFTERNOON...POSSIBLY REACHING
ADVISORY LEVELS.
WINDY AND VERY COLD WEDNESDAY NIGHT WITH A CONTINUING CHANCE OF
SNOW SHOWERS IN THE MOUNTAINS. ELSEWHERE SKIES WILL GRADUALLY
CLEAR. EXPECT LOWS OF ZERO TO 5 BELOW IN THE NORTH AND IN THE
LOWER TO MID TEENS IN THE SOUTH.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
UPR LVL CUTOFF OVER THE MARITIMES WITH ASSOCIATED DEEP SFC CYCLONE
WILL SLOWLY LIFT NE ON THURSDAY ALLOWING A MORE UPR LVL ZONAL FLOW
TO SET UP WITH AN EMBEDDED VORTICITY MAX/JET SEGMENT TO MOVE TOWARD
THE NE. THIS BRINGS A WEAK SFC LOW AND LEADING WRM FNT TOWARD NEW
ENGLAND. THESE FEATURES CROSS NEW ENGLAND THURSDAY NGT CREATING
CLOUDS AND SOME -SN. ON FRIDAY A SECOND UPR LVL VORTICITY MAX/JET
SEGMENT IN THE WESTERLY FLOW ALOFT MOVES THRU WITH ANOTHER WEAK SFC
LOW AND ROUND OF SOME -SN.
THIS IS FOLLOWED BY A STRONG UPR LVL SHORT WAVE/VORTICITY MAX ON
SATURDAY. THIS FORMS A SFC LOW ALONG THE MID ATLANTIC COAST THAT
STRENGTHENS AS IT MOVES EAST INTO THE ATLANTIC. THE CURRENT TRACK IS
TOO FAR S TO PROVIDE MUCH IN THE WAY OF PRCP FOR THE FCST AREA...
BUT SOME -SN CAN`T BE RULED OUT...ESPECIALLY IF IT ENDS UP TRACKING
A BIT FURTHER N.
AN UPR LVL RIDGE FOLLOWS THE TROF WITH A SFC RIDGE OF HIGH PRES
CROSSING THE REGION SATURDAY NGT PROVIDING FAIR WX. YET ANOTHER UPR
LVL SHORT WAVE MOVES E INTO THE REGION ON SUNDAY. CURRENT MODEL
FORECASTS SHOW THIS AS A STRONG UPR LVL SYSTEM WHICH BRINGS A SFC
LOW E FROM THE UPR GREAT LAKES TOWARD NRN NEW ENGLAND SUNDAY THEN
CROSSES NRN NEW ENGLAND SUNDAY NGT. THE TRACK OF THIS LOW MAY
BRING IN ENOUGH WARM AIR SO THAT PRCP IS NOT CONFINED TO
SN...THERE COULD BE RA OR EVEN MIXED SN/ICE/RA WITH THIS
EVENT...WITH RA MORE LIKELY ALONG THE COAST AND THE N/MT ZONES
MORE LIKELY TO SEE SN. LOTS OF TIME UNTIL THIS EVENT FOR THE TRACK
AND/OR INTENSITY OF THIS SYSTEM TO CHANGE.
THE LOW INTENSIFIES OVER THE MARITIMES ON MONDAY BRINGING IN MUCH
COLDER CANADIAN AIR ON INCREASING AND VERY GUSTY NW WINDS. -SHSN
PSBL ON MONDAY...ESPECIALLY ACROSS THE N/MT ZONES DUE TO OROGRAPHIC
LIFTING UNDER THE UPR LVL CYCLONIC FLOW. THE COLD BLUSTER WX
CONTINUES MONDAY NGT AND TUESDAY.
GENERALLY USED GFS40...HPC QPF AND BLEND OF MAV/MET MOS FOR THURSDAY
AND THURSDAY NGT. USED GMOS FOR REST OF THE LONG TERM FCST...EXCEPT
USED A BLEND OF GFS AND MEX MOS GUIDANCE FOR MAX AND MIN TEMPS.
&&
.AVIATION /04Z WEDNESDAY THROUGH SUNDAY/...
SHORT TERM...MVFR/IFR CEILINGS DEVELOPING THIS EVENING...IMPROVING
TO VFR WEDNESDAY MORNING. VFR WEDNESDAY NIGHT WITH AREAS OF MVFR
CEILINGS AND VSBY IN SNOW SHOWERS IN THE NORTH.
LONG TERM /THURSDAY THROUGH SUNDAY/...MVFR TO MAYBE IFR
CONDITIONS PSBL THURSDAY NGT THRU FRIDAY AS A SERIES OF WEAK
SYSTEMS BRING THE POTENTIAL FOR SOME LGT SN. A STRONGER SYSTEM
BRINGS THE CHC FOR SN AND IFR CONDITIONS ON SATURDAY FOLLOWED BY
ANOTHER STRENGTHENING LOW PRES SYSTEM BRINGING A CHC OF MIXED PRCP
AND IFR CONDITIONS ON SUNDAY.
&&
.MARINE...
SHORT TERM...GALE WARNING THROUGH TONIGHT. RAISED SEAS RELYING
HEAVILY ON THE SWAN GFS MODEL.
LONG TERM /THURSDAY THROUGH SUNDAY/...CD NW FLOW ON THURSDAY MAY
RESULT IN CONTINUED GALE FORCE WINDS... AT LEAST THRU THE MORNING.
THE PRES GRADIENT LETS UP LATER IN THE DAY AS WINDS AND SEAS
SUBSIDE. A SERIES OF WEAK LOW PRES SYSTEMS MOVE THRU THURSDAY NGT
AND FRIDAY BUT CONDITIONS LIKELY TO STAY BELOW SCA LEVELS. LOW
PRES PASSES WELL TO THE S ON SATURDAY SO AGAIN CONDITIONS LIKELY
TO REMAIN BELOW SCA THRESHOLDS. A STRONGER LOW PRES SYSTEM MOVES
IN FOR SUNDAY WHICH MAY PRODUCE SCA WINDS AND SEAS.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...WIND ADVISORY UNTIL 5 AM EST WEDNESDAY FOR MEZ023>028.
NH...WIND ADVISORY UNTIL 5 AM EST WEDNESDAY FOR NHZ014.
MARINE...GALE WARNING UNTIL 5 AM EST WEDNESDAY FOR ANZ150>154.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1246 PM EST WED DEC 28 2011
UPDATED AVIATION DISCUSSION FOR 18Z TAFS
.UPDATE...
LES CONTINUES ACROSS MARQUETTE AND ALGER COUNTIES AS THE FLOW
REMAINS NORTHERLY OFF THE LAKE. WITH THE RIDGE AXIS OVERHEAD...THE
FLOW SHOULD SHIFT TO THE SOUTH THIS AFTERNOON CAUSING THE LES TO END
RATHER QUICKLY. SOME LIGHT SNOW/FLURRIES OVER MN ASSOCIATED WITH
LEADING WARM ADVECTION WILL MOVE INTO WESTERN UPPER MI LATER THIS
AFTERNOON BUT SHOULD BE OF LITTLE CONSEQUENCE. NO MAJOR CHANGES TO
THE AFTERNOON FORECAST.
BASED ON THE LATEST MODEL GUIDANCE...DID MAKE SOME SUBSTANTIAL
CHANGES TO THE OVERNIGHT AND THURSDAY FORECAST FOR THE EASTERN PART
OF THE FORECAST AREA. LOW PRESSURE OVER THE WESTERN DAKOTAS WILL
MOVE TO THE WESTERN GREAT LAKES LATER TONIGHT INTO THURSDAY. THIS
WILL PUT UPPER MICHIGAN IN A BROAD AREA OF ISENTROPIC LIFT/WARM
ADVECTION. WITH THE BOUNDARY LAYER FLOW BEING SOUTH-SOUTHEAST LATE
TONIGHT INTO THURSDAY COMBINED WITH 850MB TEMPS INITIALLY AROUND
-11C (RISING TO -5C BY THU AFTN)...LAKE ENHANCED SNOW OFF OF LAKE
MICHIGAN SEEMS MORE AND MORE LIKELY FOR SCHOOLCRAFT AND SOUTHERN
LUCE COUNTIES. IN FACT...THE HIGHER RESOLUTION MODEL OUTPUT SUCH AS
THE 4KM NAM NEST INDICATE UP TO 0.7 INCH OF LIQUID LATER TONIGHT
INTO THURSDAY GENERALLY SOUTH OF M-28 IN SCHOOLCRAFT AND LUCE
COUNTIES. STILL NEED TO TAKE A CLOSER LOOK AT THE 12Z RUNS...BUT
GIVEN THAT THIS IS A GOOD SETUP FOR MODERATE TO HEAVY SNOW TO FALL
OFF OF LAKE MICHIGAN IN SCHOOLCRAFT COUNTY...HAVE OPTED TO RAISE
SNOW AMOUNTS TO A STORM TOTAL OF 3-6 INCHES AND RAISE POPS TO
CATEGORICAL FOR THE SAME AREAS. MAY NEED TO ISSUE SOME HEADLINE TO
ADDRESS THE SNOWFALL FOR THE EASTERN FORECAST AREA...HOWEVER IT IS
STILL UNCLEAR IF A WARNING OR ADVISORY WILL BE NEEDED. THIS DECISION
WILL LIKELY BE MADE LATER THIS AFTERNOON.
OTHERWISE...THE REMAINDER OF THE AREA WILL SEE A GENERAL 1-3 INCH
SNOWFALL WITH 700MB MIXING RATIO OF 2 G/KM OVERNIGHT INTO THU
MORNING.
&&
.SYNOPSIS...
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH FROM
NE CANADA INTO ERN GREAT LAKES AND A FLAT RIDGE OVER THE WEST
RESULTING IN NW FLOW FROM THE CANADIAN PRAIRIE THROUGH THE WRN GREAT
LAKES. A SHEARED UPSTREAM SHORTWAVE TROUGH WAS MOVING INTO MANITOBA
WHILE ANOTHER IN THE FAST WRLY FLOW OFF THE NE PACIFIC WAS LOCATED
OVER SRN BC. AT THE SFC...A RIDGE EXTENDED FROM NRN ONTARIO INTO WRN
WI LEAVING NRLY FLOW ACROSS LAKE SUPERIOR. 850 MB TEMPS AROUND -15C
PROVIDED PLENTY OF INSTABILITY FOR LINGERING LES EVEN THROUGH VERY
DRY AIR UPSTREAM AND INVERSION HEIGHTS DOWN TO AROUND 3K-4K FT.
&&
.DISCUSSION...
TODAY...EXPECT THAT THE LES WILL DIMINISH THIS MORNING AND END BY
THIS AFTERNOON AS THE RIDGE MOVES ACROSS UPPER MICHIGAN AND WINDS
BECOME OFFSHORE. ANY ACCUMULATIONS WITH SCT -SHSN INTO THE N CNTRL
CWA THIS MORNING SHOULD AMOUNT TO LESS THAN AN INCH. RETURN SRLY
FLOW WILL ALLOW MAX TEMPS TO REBOUND INTO THE UPPER TEENS AND LOWER
20S.
TONIGHT INTO THU...MODELS SUGGEST THAT THE THE MID TO UPPER LEVEL
FORCING WITH THE COMBINATION OF THE MANITOBA AND BC SHORTWAVES
PASSING TO THE NORTH AND SOUTH OF UPPER MI WILL BE RELATIVELY
MODEST. HOWEVER...AN AREA OF 285K-290K ISENTROPIC LIFT NORTH OF THE
850 MB LOW WILL SUPPORT WIDESPREAD LIGHT SNOW...MAINLY BTWN 06Z-18Z.
WITH 2G-3G/KG AVBL...CONSENSUS QPF VALUES IN THE 0.1 TO 0.2...AND
SNOW WATER RATIO VALUES NEAR 15/1...PREVIOUS FCST OF 1 TO 3 INCHES
LOOKS ON TRACK.
THERE IS GREATER UNCERTAINTY WITH THE POTENTIAL FOR HIGHER LAKE
ENHANCED SNOW AMOUNTS WITH SRLY FLOW OFF OF LAKE MICHIGAN. THE HPC
AND LCLY RUN HIGH RES WRF/ARW AS WELL AS THE CANADIAN REGIONAL GEM
SUGGEST THAT A BAND MAY DEVELOP INTO WRN MACKINAC COUNTY LATE
TONIGHT INTO EARLY THU AIDED BY LEVEL LEVEL CONV NEAR THE NW LOWER
MI SHORE. THE BAND MAY SHIFT FARTHER WEST INTO SRN LUCE AND SRN
SCHOOLCRAFT COUNTIES AS WINDS BACK IN RESPONSE TO THE WEAK SFC LOW
MOVING TOWARD NRN LAKE MICHIGAN. ADDITIONAL SNOWFALL AMOUNTS OF
SEVERAL INCHES COULD PUSH OVERALL AMOUNTS INTO THE ADVY CATEGORY IF
THE BANDS DEVELOP AND PERSIST LONG ENOUGH AT ANY LOCATION.
HOWEVER...CONFIDENCE IS BELOW AVERAGE WITH THESE DETAILS.
THU NIGHT INTO FRI...LEFT OVER LIGHT SNOW OVER THE ERN PORTION OF
THE CWA WILL GRADUALLY SLIDE OFF TO THE EAST AS WEAKER ISENTROPIC
LIFT AND FGEN EXIT THE AREA. THE PATH OF THE NEXT SHORTWAVE REMAINS
FAR ENOUGH SOUTH...PER GFS/ECMWF SO THAT FRI WILL REMAIN MAINLY DRY.
SO...ONLY SLIGHT CHANCE POPS WERE INCLUDED.
SAT THROUGH TUE...A PROGRESSIVE MID LEVEL TROUGH MOVES INTO THE
PLAINS BRINGING WAA SAT. WITH LITTLE MOISTURE AVBL...LITTLE/NO
MEASURABLE PCPN IS EXPECTED. THE GFS HAS TRENDED TOWARD THE
GEM/ECMWF WITH TRANSITION TOWARD A MORE AMPLIFIED/MERIDIONAL PATTERN
BY LATE SUN INTO MON. AN INFLUX OF COLD AIR (850 MB TEMPS DOWN INTO
THE -17C TO -20C RANGE) BEHIND A COLD FRONT LATE SUN WITH DEEP
MOISTURE AVAILABLE SHOULD BRING LES TO LOCATIONS FAVORED BY NW TO N
FLOW TIL RIDING MOVES BACK IN BY TUE.
&&
.AVIATION /FOR THE 18Z TAF ISSUANCE/...
EXPECT ANY REMAINING MVFR CIGS TO DISSIPATE EARLY THIS AFTN AT CMX
AND SAW AS FLOW TURNS SOUTHERLY AND THE LES CLOUDS MOVE OFFSHORE.
THE NEXT SYSTEM OVER THE PLAINS WILL APPROACH THE AREA TONIGHT. SOME
LIGHT SNOW MAY SPREAD INTO IWD THIS AFTERNOON AS A WEAK WARM FRONT
APPROACHES THE AREA. WIDESPREAD IFR CIGS AND VSBYS WILL SPREAD
ACROSS THE AREA OVERNIGHT AS THE LOW MOVES INTO WISCONSIN...WITH
LIFR POSSIBLE THU MORNING UNDER THE HEAVIEST SNOW. CONTINUED
IFR/LIFR ON THU AS THE LOW EXITS TO THE EAST.
&&
.MARINE /FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE/...
AS HIGH PRESSURE MOVES OVER LAKE SUPERIOR TODAY...WINDS WILL
DECREASE AND BECOME MORE SOUTHERLY THROUGH THE DAY. THE NEXT CHANCE
FOR SIGNIFICANT WINDS WILL COME OVER THE WEEKEND AS A LOW PRESSURE
SYSTEM MOVES NORTH OF LAKE SUPERIOR. THE STRONGEST WINDS WILL COME
ON SUNDAY FROM THE NW...AND MAY REACH GALE FORCE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...MRD
SYNOPSIS...JLB
DISCUSSION...JLB
AVIATION...MRD
MARINE...TITUS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1126 AM EST WED DEC 28 2011
.UPDATE...
LES CONTINUES ACROSS MARQUETTE AND ALGER COUNTIES AS THE FLOW
REMAINS NORTHERLY OFF THE LAKE. WITH THE RIDGE AXIS OVERHEAD...THE
FLOW SHOULD SHIFT TO THE SOUTH THIS AFTERNOON CAUSING THE LES TO END
RATHER QUICKLY. SOME LIGHT SNOW/FLURRIES OVER MN ASSOCIATED WITH
LEADING WARM ADVECTION WILL MOVE INTO WESTERN UPPER MI LATER THIS
AFTERNOON BUT SHOULD BE OF LITTLE CONSEQUENCE. NO MAJOR CHANGES TO
THE AFTERNOON FORECAST.
BASED ON THE LATEST MODEL GUIDANCE...DID MAKE SOME SUBSTANTIAL
CHANGES TO THE OVERNIGHT AND THURSDAY FORECAST FOR THE EASTERN PART
OF THE FORECAST AREA. LOW PRESSURE OVER THE WESTERN DAKOTAS WILL
MOVE TO THE WESTERN GREAT LAKES LATER TONIGHT INTO THURSDAY. THIS
WILL PUT UPPER MICHIGAN IN A BROAD AREA OF ISENTROPIC LIFT/WARM
ADVECTION. WITH THE BOUNDARY LAYER FLOW BEING SOUTH-SOUTHEAST LATE
TONIGHT INTO THURSDAY COMBINED WITH 850MB TEMPS INITIALLY AROUND
-11C (RISING TO -5C BY THU AFTN)...LAKE ENHANCED SNOW OFF OF LAKE
MICHIGAN SEEMS MORE AND MORE LIKELY FOR SCHOOLCRAFT AND SOUTHERN
LUCE COUNTIES. IN FACT...THE HIGHER RESOLUTION MODEL OUTPUT SUCH AS
THE 4KM NAM NEST INDICATE UP TO 0.7 INCH OF LIQUID LATER TONIGHT
INTO THURSDAY GENERALLY SOUTH OF M-28 IN SCHOOLCRAFT AND LUCE
COUNTIES. STILL NEED TO TAKE A CLOSER LOOK AT THE 12Z RUNS...BUT
GIVEN THAT THIS IS A GOOD SETUP FOR MODERATE TO HEAVY SNOW TO FALL
OFF OF LAKE MICHIGAN IN SCHOOLCRAFT COUNTY...HAVE OPTED TO RAISE
SNOW AMOUNTS TO A STORM TOTAL OF 3-6 INCHES AND RAISE POPS TO
CATEGORICAL FOR THE SAME AREAS. MAY NEED TO ISSUE SOME HEADLINE TO
ADDRESS THE SNOWFALL FOR THE EASTERN FORECAST AREA...HOWEVER IT IS
STILL UNCLEAR IF A WARNING OR ADVISORY WILL BE NEEDED. THIS DECISION
WILL LIKELY BE MADE LATER THIS AFTERNOON.
OTHERWISE...THE REMAINDER OF THE AREA WILL SEE A GENERAL 1-3 INCH
SNOWFALL WITH 700MB MIXING RATIO OF 2 G/KM OVERNIGHT INTO THU
MORNING.
&&
PREV DISCUSSION...ISSUED AT 623 AM EST WED DEC 28 2011...
.SYNOPSIS...
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH FROM
NE CANADA INTO ERN GREAT LAKES AND A FLAT RIDGE OVER THE WEST
RESULTING IN NW FLOW FROM THE CANADIAN PRAIRIE THROUGH THE WRN GREAT
LAKES. A SHEARED UPSTREAM SHORTWAVE TROUGH WAS MOVING INTO MANITOBA
WHILE ANOTHER IN THE FAST WRLY FLOW OFF THE NE PACIFIC WAS LOCATED
OVER SRN BC. AT THE SFC...A RIDGE EXTENDED FROM NRN ONTARIO INTO WRN
WI LEAVING NRLY FLOW ACROSS LAKE SUPERIOR. 850 MB TEMPS AROUND -15C
PROVIDED PLENTY OF INSTABILITY FOR LINGERING LES EVEN THROUGH VERY
DRY AIR UPSTREAM AND INVERSION HEIGHTS DOWN TO AROUND 3K-4K FT.
&&
.DISCUSSION...
TODAY...EXPECT THAT THE LES WILL DIMINISH THIS MORNING AND END BY
THIS AFTERNOON AS THE RIDGE MOVES ACROSS UPPER MICHIGAN AND WINDS
BECOME OFFSHORE. ANY ACCUMULATIONS WITH SCT -SHSN INTO THE N CNTRL
CWA THIS MORNING SHOULD AMOUNT TO LESS THAN AN INCH. RETURN SRLY
FLOW WILL ALLOW MAX TEMPS TO REBOUND INTO THE UPPER TEENS AND LOWER
20S.
TONIGHT INTO THU...MODELS SUGGEST THAT THE THE MID TO UPPER LEVEL
FORCING WITH THE COMBINATION OF THE MANITOBA AND BC SHORTWAVES
PASSING TO THE NORTH AND SOUTH OF UPPER MI WILL BE RELATIVELY
MODEST. HOWEVER...AN AREA OF 285K-290K ISENTROPIC LIFT NORTH OF THE
850 MB LOW WILL SUPPORT WIDESPREAD LIGHT SNOW...MAINLY BTWN 06Z-18Z.
WITH 2G-3G/KG AVBL...CONSENSUS QPF VALUES IN THE 0.1 TO 0.2...AND
SNOW WATER RATIO VALUES NEAR 15/1...PREVIOUS FCST OF 1 TO 3 INCHES
LOOKS ON TRACK.
THERE IS GREATER UNCERTAINTY WITH THE POTENTIAL FOR HIGHER LAKE
ENHANCED SNOW AMOUNTS WITH SRLY FLOW OFF OF LAKE MICHIGAN. THE HPC
AND LCLY RUN HIGH RES WRF/ARW AS WELL AS THE CANADIAN REGIONAL GEM
SUGGEST THAT A BAND MAY DEVELOP INTO WRN MACKINAC COUNTY LATE
TONIGHT INTO EARLY THU AIDED BY LEVEL LEVEL CONV NEAR THE NW LOWER
MI SHORE. THE BAND MAY SHIFT FARTHER WEST INTO SRN LUCE AND SRN
SCHOOLCRAFT COUNTIES AS WINDS BACK IN RESPONSE TO THE WEAK SFC LOW
MOVING TOWARD NRN LAKE MICHIGAN. ADDITIONAL SNOWFALL AMOUNTS OF
SEVERAL INCHES COULD PUSH OVERALL AMOUNTS INTO THE ADVY CATEGORY IF
THE BANDS DEVELOP AND PERSIST LONG ENOUGH AT ANY LOCATION.
HOWEVER...CONFIDENCE IS BELOW AVERAGE WITH THESE DETAILS.
THU NIGHT INTO FRI...LEFT OVER LIGHT SNOW OVER THE ERN PORTION OF
THE CWA WILL GRADUALLY SLIDE OFF TO THE EAST AS WEAKER ISENTROPIC
LIFT AND FGEN EXIT THE AREA. THE PATH OF THE NEXT SHORTWAVE REMAINS
FAR ENOUGH SOUTH...PER GFS/ECMWF SO THAT FRI WILL REMAIN MAINLY DRY.
SO...ONLY SLIGHT CHANCE POPS WERE INCLUDED.
SAT THROUGH TUE...A PROGRESSIVE MID LEVEL TROUGH MOVES INTO THE
PLAINS BRINGING WAA SAT. WITH LITTLE MOISTURE AVBL...LITTLE/NO
MEASURABLE PCPN IS EXPECTED. THE GFS HAS TRENDED TOWARD THE
GEM/ECMWF WITH TRANSITION TOWARD A MORE AMPLIFIED/MERIDIONAL PATTERN
BY LATE SUN INTO MON. AN INFLUX OF COLD AIR (850 MB TEMPS DOWN INTO
THE -17C TO -20C RANGE) BEHIND A COLD FRONT LATE SUN WITH DEEP
MOISTURE AVAILABLE SHOULD BRING LES TO LOCATIONS FAVORED BY NW TO N
FLOW TIL RIDING MOVES BACK IN BY TUE.
&&
.AVIATION /FOR THE 12Z TAF ISSUANCE/...
EXPECT LINGERING LES TO WANE THIS MORNING AS THE FLOW BECOMES MORE
ANTICYCLONIC AND VERY DRY AIR UPSTREAM OF LAKE SUPERIOR HAS AN
IMPACT. BUT WITH LINGERING LOW INVERSION BASE AND VERY CHILLY
AIRMASS PASSING OVER LAKE SUPERIOR...EXPECT MVFR CIGS TO LINGER INTO
THIS MORNING. AFTER THE LOW CLOUDS BREAK UP...VFR CONDITIONS WILL
THEN PREVAIL THROUGH MUCH OF THE DAY. ANOTHER BAND OF THICKER
CLOUDS/-SN WILL ARRIVE TOWARD EVENING WITH LOW END VFR/HIGH END MVFR
CONDITIONS. THE BEST CHANCE FOR THE MVFR CIGS WILL BE AT THE FARTHER
N CMX LOCATION.
&&
.MARINE /FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE/...
AS HIGH PRESSURE MOVES OVER LAKE SUPERIOR TODAY...WINDS WILL
DECREASE AND BECOME MORE SOUTHERLY THROUGH THE DAY. THE NEXT CHANCE
FOR SIGNIFICANT WINDS WILL COME OVER THE WEEKEND AS A LOW PRESSURE
SYSTEM MOVES NORTH OF LAKE SUPERIOR. THE STRONGEST WINDS WILL COME
ON SUNDAY FROM THE NW...AND MAY REACH GALE FORCE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...MRD
SYNOPSIS...JLB
DISCUSSION...JLB
AVIATION...TITUS
MARINE...TITUS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
623 AM EST WED DEC 28 2011
UPDATED AVIATION DISCUSSION FOR 12Z TAFS
.SYNOPSIS...
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH FROM
NE CANADA INTO ERN GREAT LAKES AND A FLAT RIDGE OVER THE WEST
RESULTING IN NW FLOW FROM THE CANADIAN PRAIRIE THROUGH THE WRN GREAT
LAKES. A SHEARED UPSTREAM SHORTWAVE TROUGH WAS MOVING INTO MANITOBA
WHILE ANOTHER IN THE FAST WRLY FLOW OFF THE NE PACIFIC WAS LOCATED
OVER SRN BC. AT THE SFC...A RIDGE EXTENDED FROM NRN ONTARIO INTO WRN
WI LEAVING NRLY FLOW ACROSS LAKE SUPERIOR. 850 MB TEMPS AROUND -15C
PROVIDED PLENTY OF INSTABILITY FOR LINGERING LES EVEN THROUGH VERY
DRY AIR UPSTREAM AND INVERSION HEIGHTS DOWN TO AROUND 3K-4K FT.
&&
.DISCUSSION...
TODAY...EXPECT THAT THE LES WILL DIMINISH THIS MORNING AND END BY
THIS AFTERNOON AS THE RIDGE MOVES ACROSS UPPER MICHIGAN AND WINDS
BECOME OFFSHORE. ANY ACCUMULATIONS WITH SCT -SHSN INTO THE N CNTRL
CWA THIS MORNING SHOULD AMOUNT TO LESS THAN AN INCH. RETURN SRLY
FLOW WILL ALLOW MAX TEMPS TO REBOUND INTO THE UPPER TEENS AND LOWER
20S.
TONIGHT INTO THU...MODELS SUGGEST THAT THE THE MID TO UPPER LEVEL
FORCING WITH THE COMBINATION OF THE MANITOBA AND BC SHORTWAVES
PASSING TO THE NORTH AND SOUTH OF UPPER MI WILL BE RELATIVELY
MODEST. HOWEVER...AN AREA OF 285K-290K ISENTROPIC LIFT NORTH OF THE
850 MB LOW WILL SUPPORT WIDESPREAD LIGHT SNOW...MAINLY BTWN 06Z-18Z.
WITH 2G-3G/KG AVBL...CONSENSUS QPF VALUES IN THE 0.1 TO 0.2...AND
SNOW WATER RATIO VALUES NEAR 15/1...PREVIOUS FCST OF 1 TO 3 INCHES
LOOKS ON TRACK.
THERE IS GREATER UNCERTAINTY WITH THE POTENTIAL FOR HIGHER LAKE
ENHANCED SNOW AMOUNTS WITH SRLY FLOW OFF OF LAKE MICHIGAN. THE HPC
AND LCLY RUN HIGH RES WRF/ARW AS WELL AS THE CANADIAN REGIONAL GEM
SUGGEST THAT A BAND MAY DEVELOP INTO WRN MACKINAC COUNTY LATE
TONIGHT INTO EARLY THU AIDED BY LEVEL LEVEL CONV NEAR THE NW LOWER
MI SHORE. THE BAND MAY SHIFT FARTHER WEST INTO SRN LUCE AND SRN
SCHOOLCRAFT COUNTIES AS WINDS BACK IN RESPONSE TO THE WEAK SFC LOW
MOVING TOWARD NRN LAKE MICHIGAN. ADDITIONAL SNOWFALL AMOUNTS OF
SEVERAL INCHES COULD PUSH OVERALL AMOUNTS INTO THE ADVY CATEGORY IF
THE BANDS DEVELOP AND PERSIST LONG ENOUGH AT ANY LOCATION.
HOWEVER...CONFIDENCE IS BELOW AVERAGE WITH THESE DETAILS.
THU NIGHT INTO FRI...LEFT OVER LIGHT SNOW OVER THE ERN PORTION OF
THE CWA WILL GRADUALLY SLIDE OFF TO THE EAST AS WEAKER ISENTROPIC
LIFT AND FGEN EXIT THE AREA. THE PATH OF THE NEXT SHORTWAVE REMAINS
FAR ENOUGH SOUTH...PER GFS/ECMWF SO THAT FRI WILL REMAIN MAINLY DRY.
SO...ONLY SLIGHT CHANCE POPS WERE INCLUDED.
SAT THROUGH TUE...A PROGRESSIVE MID LEVEL TROUGH MOVES INTO THE
PLAINS BRINGING WAA SAT. WITH LITTLE MOISTURE AVBL...LITTLE/NO
MEASURABLE PCPN IS EXPECTED. THE GFS HAS TRENDED TOWARD THE
GEM/ECMWF WITH TRANSITION TOWARD A MORE AMPLIFIED/MERIDIONAL PATTERN
BY LATE SUN INTO MON. AN INFLUX OF COLD AIR (850 MB TEMPS DOWN INTO
THE -17C TO -20C RANGE) BEHIND A COLD FRONT LATE SUN WITH DEEP
MOISTURE AVAILABLE SHOULD BRING LES TO LOCATIONS FAVORED BY NW TO N
FLOW TIL RIDING MOVES BACK IN BY TUE.
&&
.AVIATION /FOR THE 12Z TAF ISSUANCE/...
EXPECT LINGERING LES TO WANE THIS MORNING AS THE FLOW BECOMES MORE
ANTICYCLONIC AND VERY DRY AIR UPSTREAM OF LAKE SUPERIOR HAS AN
IMPACT. BUT WITH LINGERING LOW INVERSION BASE AND VERY CHILLY
AIRMASS PASSING OVER LAKE SUPERIOR...EXPECT MVFR CIGS TO LINGER INTO
THIS MORNING. AFTER THE LOW CLOUDS BREAK UP...VFR CONDITIONS WILL
THEN PREVAIL THROUGH MUCH OF THE DAY. ANOTHER BAND OF THICKER
CLOUDS/-SN WILL ARRIVE TOWARD EVENING WITH LOW END VFR/HIGH END MVFR
CONDITIONS. THE BEST CHANCE FOR THE MVFR CIGS WILL BE AT THE FARTHER
N CMX LOCATION.
&&
.MARINE /FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE/...
AS HIGH PRESSURE MOVES OVER LAKE SUPERIOR TODAY...WINDS WILL
DECREASE AND BECOME MORE SOUTHERLY THROUGH THE DAY. THE NEXT CHANCE
FOR SIGNIFICANT WINDS WILL COME OVER THE WEEKEND AS A LOW PRESSURE
SYSTEM MOVES NORTH OF LAKE SUPERIOR. THE STRONGEST WINDS WILL COME
ON SUNDAY FROM THE NW...AND MAY REACH GALE FORCE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...JLB
DISCUSSION...JLB
AVIATION...TITUS
MARINE...TITUS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
552 AM EST WED DEC 28 2011
.SYNOPSIS...
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH FROM
NE CANADA INTO ERN GREAT LAKES AND A FLAT RIDGE OVER THE WEST
RESULTING IN NW FLOW FROM THE CANADIAN PRAIRIE THROUGH THE WRN GREAT
LAKES. A SHEARED UPSTREAM SHORTWAVE TROUGH WAS MOVING INTO MANITOBA
WHILE ANOTHER IN THE FAST WRLY FLOW OFF THE NE PACIFIC WAS LOCATED
OVER SRN BC. AT THE SFC...A RIDGE EXTENDED FROM NRN ONTARIO INTO WRN
WI LEAVING NRLY FLOW ACROSS LAKE SUPERIOR. 850 MB TEMPS AROUND -15C
PROVIDED PLENTY OF INSTABILITY FOR LINGERING LES EVEN THROUGH VERY
DRY AIR UPSTREAM AND INVERSION HEIGHTS DOWN TO AROUND 3K-4K FT.
&&
.DISCUSSION...
TODAY...EXPECT THAT THE LES WILL DIMINISH THIS MORNING AND END BY
THIS AFTERNOON AS THE RIDGE MOVES ACROSS UPPER MICHIGAN AND WINDS
BECOME OFFSHORE. ANY ACCUMULATIONS WITH SCT -SHSN INTO THE N CNTRL
CWA THIS MORNING SHOULD AMOUNT TO LESS THAN AN INCH. RETURN SRLY
FLOW WILL ALLOW MAX TEMPS TO REBOUND INTO THE UPPER TEENS AND LOWER
20S.
TONIGHT INTO THU...MODELS SUGGEST THAT THE THE MID TO UPPER LEVEL
FORCING WITH THE COMBINATION OF THE MANITOBA AND BC SHORTWAVES
PASSING TO THE NORTH AND SOUTH OF UPPER MI WILL BE RELATIVELY
MODEST. HOWEVER...AN AREA OF 285K-290K ISENTROPIC LIFT NORTH OF THE
850 MB LOW WILL SUPPORT WIDESPREAD LIGHT SNOW...MAINLY BTWN 06Z-18Z.
WITH 2G-3G/KG AVBL...CONSENSUS QPF VALUES IN THE 0.1 TO 0.2...AND
SNOW WATER RATIO VALUES NEAR 15/1...PREVIOUS FCST OF 1 TO 3 INCHES
LOOKS ON TRACK.
THERE IS GREATER UNCERTAINTY WITH THE POTENTIAL FOR HIGHER LAKE
ENHANCED SNOW AMOUNTS WITH SRLY FLOW OFF OF LAKE MICHIGAN. THE HPC
AND LCLY RUN HIGH RES WRF/ARW AS WELL AS THE CANADIAN REGIONAL GEM
SUGGEST THAT A BAND MAY DEVELOP INTO WRN MACKINAC COUNTY LATE
TONIGHT INTO EARLY THU AIDED BY LEVEL LEVEL CONV NEAR THE NW LOWER
MI SHORE. THE BAND MAY SHIFT FARTHER WEST INTO SRN LUCE AND SRN
SCHOOLCRAFT COUNTIES AS WINDS BACK IN RESPONSE TO THE WEAK SFC LOW
MOVING TOWARD NRN LAKE MICHIGAN. ADDITIONAL SNOWFALL AMOUNTS OF
SEVERAL INCHES COULD PUSH OVERALL AMOUNTS INTO THE ADVY CATEGORY IF
THE BANDS DEVELOP AND PERSIST LONG ENOUGH AT ANY LOCATION.
HOWEVER...CONFIDENCE IS BELOW AVERAGE WITH THESE DETAILS.
THU NIGHT INTO FRI...LEFT OVER LIGHT SNOW OVER THE ERN PORTION OF
THE CWA WILL GRADUALLY SLIDE OFF TO THE EAST AS WEAKER ISENTROPIC
LIFT AND FGEN EXIT THE AREA. THE PATH OF THE NEXT SHORTWAVE REMAINS
FAR ENOUGH SOUTH...PER GFS/ECMWF SO THAT FRI WILL REMAIN MAINLY DRY.
SO...ONLY SLIGHT CHANCE POPS WERE INCLUDED.
SAT THROUGH TUE...A PROGRESSIVE MID LEVEL TROUGH MOVES INTO THE
PLAINS BRINGING WAA SAT. WITH LITTLE MOISTURE AVBL...LITTLE/NO
MEASURABLE PCPN IS EXPECTED. THE GFS HAS TRENDED TOWARD THE
GEM/ECMWF WITH TRANSITION TOWARD A MORE AMPLIFIED/MERIDIONAL PATTERN
BY LATE SUN INTO MON. AN INFLUX OF COLD AIR (850 MB TEMPS DOWN INTO
THE -17C TO -20C RANGE) BEHIND A COLD FRONT LATE SUN WITH DEEP
MOISTURE AVAILABLE SHOULD BRING LES TO LOCATIONS FAVORED BY NW TO N
FLOW TIL RIDING MOVES BACK IN BY TUE.
&&
.AVIATION /FOR THE 06Z TAF ISSUANCE/...
EXPECT LINGERING LES TO WANE EARLY THIS MRNG AS THE FLOW BECOMES
MORE ACYC AND VERY DRY AIR UPSTREAM OF LK SUP HAS AN IMPACT. BUT
WITH LINGERING LO INVRN BASE AND VERY CHILLY AIRMASS PASSING OVER LK
SUP...EXPECT MVFR CIGS TO LINGER THRU SUNRISE. THE CLDS MAY BREAK UP
A BIT EARLIER AT IWD CLOSER TO INCOMING HI PRES RDG. AFT THE LO CLDS
BREAK UP...VFR CONDITIONS WL THEN PREVAIL THRU MUCH OF THE DAY.
ANOTHER BAND OF THICKER CLDS/-SN WL ARRIVE TOWARD EVNG WITH LO END
VFR/HI END MVFR CONDITIONS. THE BEST CHC FOR THE MVFR CIGS WL BE AT
THE FARTHER N CMX LOCATION.
&&
.MARINE /FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE/...
AS HIGH PRESSURE MOVES OVER LAKE SUPERIOR TODAY...WINDS WILL
DECREASE AND BECOME MORE SOUTHERLY THROUGH THE DAY. THE NEXT CHANCE
FOR SIGNIFICANT WINDS WILL COME OVER THE WEEKEND AS A LOW PRESSURE
SYSTEM MOVES NORTH OF LAKE SUPERIOR. THE STRONGEST WINDS WILL COME
ON SUNDAY FROM THE NW...AND MAY REACH GALE FORCE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...JLB
DISCUSSION...JLB
AVIATION...KC
MARINE...TITUS
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
352 PM CST WED DEC 28 2011
.DISCUSSION...
SUMMARY...PATTERN IS A BIT MORE ACTIVE OVER THE NEXT SEVERAL DAYS
IN TERMS OF CHANCES OF PRECIPITATION THAN IT HAS BEEN IN QUITE
SOME TIME. OVERALL...THE OUTLOOK REMAINS WARM SO THE PRECIP EVENTS
EXPECTED TONIGHT...THURSDAY NIGHT AND SATURDAY NIGHT WILL LIKELY
HAVE SOME LIQUID PRECIPITATION ASSOCIATED WITH EACH OF THEM. NO
MAJOR SYSTEMS EXPECTED AND MAXIMUM QPF WITH EACH EVENT SHOULD
LARGELY BE BELOW A QUARTER INCH...A COUPLE OUTLIER RUNS OF THE
NAM/GEM WOULD SUGGEST HIGHER QPF TOTALS WITH THE THURSDAY NIGHT
AND SATURDAY NIGHT SYSTEMS.
THE INTERIOR OF CANADA HAS COOLED SINCE THE LAST TIME I WAS ON A
FORECAST SHIFT LATE LAST WEEK...BUT STILL NO TRUE ARCTIC AIR
ENCROACHING ON THE US CONUS. THE ARCTIC AIR IS STILL BEING
CONFINED TO THE HIGHER LATITUDES...LARGELY ABOVE 55-60 DEGREES
NORTH. PACIFIC AIR MASSES WILL CONTINUE TO IMPACT THE US THROUGH
THE END OF THE YEAR. PROGRESSIVE UPPER FLOW WILL BE FEATURED AS A
SERIES OF DISTURBANCES SURGE FROM THE NORTHEASTERN PACIFIC AND
INTO THE PACIFIC NORTHWEST. THE SOUTHWARD EXTENT OF THIS UPPER
TROUGH SHOULD BE LIMITED BY A RIDGE ACROSS THE SOUTHWEST US. AS A
RESULT...THE SWATH OF PRECIPITATION SHOULD NOT EXTEND MUCH FARTHER
SOUTH THAN 40 DEGREES NORTH. THIS WILL KEEP MN AND WI UNDER THE
GUN FOR A FEW LIGHT PRECIPITATION EVENTS OVER THE COMING DAYS.
THE FAST MOVING FLOW ALOFT WILL KEEP UNSETTLED CONDITIONS IN PLACE
FOR MUCH OF THE PACIFIC NORTHWEST...NORTHERN ROCKIES AND UPPER
MISSISSIPPI VALLEY THROUGH THE WEEKEND. THE FIRST IN A PAIR OF
SYSTEMS IS CURRENTLY MOVING OUT OF THE NORTHERN ROCKIES AND INTO
THE NORTHERN PLAINS. LIGHT RAIN IS RAPIDLY PUSHING INTO THE
EASTERN DAKOTAS LATE THIS AFTERNOON AND THE HRRR TREND IS TAKE THE
LIGHT RAIN INTO WESTERN MN BETWEEN 00-03Z. IF THE CURRENT TRENDS
HOLD...MOST OF THE PRECIP WILL PUSH OUT OF THE FORECAST AREA
BETWEEN 06-09Z...A BIT FASTER THAN THE CURRENT FORECAST INDICATES.
ALSO SOME QUESTION WHETHER OR NOT THE MIXED PRECIPITATION WILL
REALLY PAN OUT IN PARTS OF CENTRAL/SOUTHERN MN. COOLING WILL BE
TOUGH WITH CLOUD COVER AND WEAK WARM AIR ADVECTION. IT MIGHT END
UP BEING NEARLY ALL LIGHT RAIN RATHER THAN SNOW OR FREEZING RAIN.
IN THE EXTENDED...INCREASINGLY MERIDIONAL FLOW WILL LEAD TO MORE
AMPLIFIED TROUGHS ACROSS THE EASTERN PACIFIC THROUGH THE GREAT
LAKES WITH RIDGING SANDWICHED IN BETWEEN. MOST OF THE GUIDANCE
AGREES ON THIS PATTERN...OUTSIDE THE 00Z GFS WHICH WAS BROAD AND
FLAT WITH THE EASTERN TROUGH DESPITE ITS AMPLIFIED RIDGE UPSTREAM.
&&
.AVIATION.../18Z TAF ISSUANCE/
FIRST SHOT OF WAA SNOW SHOWERS/FLURRIES MOVING THROUGH EASTERN AREAS
AT THIS TIME. SHOULD EXIT THE AREA THROUGH 19Z. MAIN CONCERN IS
PRECIPITATION DEVELOPMENT OVER THE NORTHERN AND EASTERN AREAS OF THE
AREA OVERNIGHT. NEXT WAVE MOVING THROUGH NORTHEASTERN MONTANA THIS
AFTERNOON AND SHOULD SPREAD MORE MID/HIGH LEVEL CLOUDS INTO THE WEST
THROUGH 00Z. FORCING IS STRONG BUT DEEP LAYER MOISTURE IS RATHER
LIMITED. SHOULD STILL SEE SOME LIGHT QPF ALONG AND NORTH OF THE SFC
LOW TRACK. THIS WOULD AFFECT ALL TAFS WITH THE EXCEPTION OF KRWF
OVERNIGHT. PRECIPITATION TYPE ALSO A PROBLEM...AS WARM SURGE MOVES
IN WITH THE SURFACE LOW. -FZRA POSSIBLE...AT LEAST BRIEFLY...ALONG
AND NORTH OF THE LOW TRACK. SREF FREEZING RAIN PROBS INCREASE TO
30% INTO WEST CENTRAL WI LATER TONIGHT. CEILINGS ARE EXPECTED TO
DROP TO MVFR AS PRECIPITATION DEVELOPS AND COLD FRONT DROPPING IN
BEHIND...SHOULD CONTINUE LOW END MVFR CONDITIONS OVER MUCH OF THE
AREA INTO THURSDAY MORNING. SOUTHERLY SURFACE WINDS BECOMING
NORTHWEST AS LOW EXITS REGION. SHOULD REMAIN AROUND 10 KNOTS OR
LESS MOST LOCATIONS.
KMSP...MID LEVEL CLOUDS EXITING THE REGION WITH MORE MID/HIGH LEVEL
CLOUDS MOVING IN LATE AFTERNOON FROM THE WEST. STILL LOOKING AT
POSSIBILITY OF LIGHT QPF ASSOCIATED WITH THE WAVE MOVING IN LATER
TONIGHT. BEST SHOT AT PCPN STILL LOOKS LIKE 05Z-08Z. TYPE COULD BE
-RASN AND DEPENDING ON SURFACE TEMP...-FZRA A POSSIBILITY. LOW
CONFIDENCE OF THIS HAPPENING AT THE AIRPORT AT THIS TIME...MORE
LIKELY NORTH OF THE AREA. MVFR CONDS WILL DEVELOP WITH
PRECIPITATION AND LINGER THROUGH THE MORNING AS COLD AIR ADVECTION
DEVELOPS BEHIND SURFACE LOW AND COLD FRONT. SOUTHERLY SURFACE WINDS
BECOMING MORE NORTHWEST BY THURSDAY MORNING WITH PASSAGE OF SURFACE
LOW AND COLD FRONT.
NEXT WAVE MOVING IN OVER WESTERN MN LATE THURSDAY AFTERNOON AND
AFFECTING THE AREA MAINLY AFTER 03Z FRI.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
CLF/DWE
AREA FORECAST DISCUSSION
NWS DULUTH MN
1218 PM CST WED DEC 28 2011
.AVIATION.../18Z TAF ISSUANCE/
AN AREA OF LOW CLOUDS AND VERY LIGHT SNOW WILL CONTINUE TO MOVE
OFF TO THE EAST THIS AFTERNOON. HOWEVER ANOTHER AREA OF CLOUD
COVER WILL REPLACE IT OVERNIGHT TONIGHT AS ANOTHER SYSTEM FROM
CANADA TRACKS EWSEWD ACROSS THE CWA. LIGHT SNOW WILL DEVELOP
ACROSS OUR WRN ZONES THIS EVENING...THEN SPREAD EWD OVERNIGHT TO
AFFECT THE TWIN PORTS...IRON RANGE AND NWRN WI. VSBYS WITHIN THE
SNOWFALL WILL BE IN THE IFR/MVFR RANGE WHILE CIGS SHOULD BE IN THE
MVFR RANGE. THE SNOW WILL QUICKLY TAPER OFF TO SCATTERED LIGHT
SNOW SHOWERS THURSDAY MORNING BEFORE ENDING THURSDAY AFTERNOON.
&&
.PREV DISCUSSION... /ISSUED 1211 PM CST WED DEC 28 2011/
UPDATE...
SNOW AREA SPREADING EAST AS FORECAST AND HAVE UPDATED THE FORECAST
TO TAKE OUT THE SNOW FROM THE AREA WEST OF A LINE FROM INL THROUGH
DLH. SATELLITE SHOWS CLEAR SKIES BEHIND THE SNOW...BUT AREA OF LOW
CLOUDS WILL SPREAD SOUTH INTO NORTHERN MN....WHILE WAA CLOUDS WILL
MOVE IN THR THE WEST LATE THIS AFTERNOON.
PREV DISCUSSION... /ISSUED 356 AM CST WED DEC 28 2011/
SHORT TERM...THE MAIN FORECAST CONCERN IN THE SHORT TERM IS THE
AMOUNT AND LOCATION OF ACCUMULATING SNOWFALL TODAY THROUGH TONIGHT.
AT 330 AM...CLOUDS WERE INCREASING AHEAD OF A WEAK SHORTWAVE AND
UP[PER LEVEL JET MAX TRAVERSING ACROSS MN. STRONG LOW LEVEL WAA
AND THETA-E ADVECTION WAS HELPING TO GENERATE LIGHT SNOW ACROSS
WESTERN MN DESPITE INITIALLY DRY LOW LEVEL AIR. THE HRRR RAPID
REFRESH WAS DEPICTING THE AREA OF CLOUDS/LIGHT SNOW FAIRLY WELL.
THE SHORTWAVE AND 100+ KNOT UPPER LEVEL JET MAX WILL CONTINUE TO
PUSH ACROSS THE NORTHLAND TODAY...PUSHING INTO THE WESTERN GREAT
LAKES BY THIS AFTERNOON. THE LATEST HRRR ACTUALLY SHOWS THE
RETURNS DIMINISHING FOR A TIME THIS EARLY MORNING...BEFORE
INCREASING A BIT AGAIN AS THEY REACH NE MN LATER IN THE MORNING.
THINK THERE IS A CHANCE FOR ABOUT A HALF INCH OF SNOWFALL IN SPOTS
TODAY. COULD SEE A BIT MORE ALONG THE SAWTOOTH MOUNTAINS OF THE
NORTH SHORE...AS WINDS COME AROUND TO THE EAST AND SUPPORT LAKE
EFFECT SNOW SHOWERS.
A STRONGER SYSTEM WILL MOVE IN TONIGHT...AND QUICKLY EXIT THE
REGION ON THURSDAY. HAVE SHIFTED THE FOCUS FOR ACCUMULATING
SNOWFALL A BIT TO THE SOUTH BASED ON THE LATEST 00Z MODEL RUNS.
CURRENT THINKING IS THAT THERE WILL BE A STRIPE OF 1 TO 3 INCHES
FROM THE NORTHERN BRAINERD LAKES REGION...THROUGH THE TWIN PORTS
AND INTO NW WI. ALSO CANNOT RULE OUT A NARROW STRIPE OF 2 TO 4
INCHES OR POSSIBLY A BIT MORE AS THE SYSTEM DROPS TO THE SOUTHEAST
AND LAYS DOWN A SWATH OF ACCUMULATING SNOWFALL. THE NORTH SHORE
SHOULD ALSO SEE HIGHER AMOUNTS DUE TO LAKE EFFECT/LAKE
ENHANCEMENT. IN TERMS OF SURFACE LOW PRESSURE...THE MODELS ARE
FAIRLY SIMILAR...BUT QPF AMOUNTS AND LOCATION DO VARY BETWEEN THE
ECMWF/NAM/GFS AND GEM. WILL TAKE A CONSENSUS SOLUTION. MAY NEED TO
BUMP UP AMOUNTS IN LATER FORECAST PACKAGES. IN THE
GRIDS...CURRENTLY HAVE AMOUNTS SIMILAR TO WHAT IS MENTIONED ABOVE.
THINK THE SYSTEM WILL BE FAIRLY EFFICIENT AT RINGING OUT AVAILABLE
MOISTURE.
THE LOW PRESSURE SYSTEM WILL MOVE OUT OF THE REGION ON
THURSDAY...WITH A BIT OF A BREAK BEFORE THE NEXT SYSTEM ARRIVES
THURSDAY NIGHT. THE NAM SOLUTION WOULD SUPPORT HIGHER POPS FOR
THURSDAY NIGHT...BUT THE ECMWF/GFS KEEP THE ACCUMULATING SNOW
GENERALLY WEST AND SOUTH OF THE CWA.
LONG TERM...FRIDAY THROUGH TUESDAY.
FRIDAY...THE LONG TERM PERIOD BEGINS WITH LOW CHANCES OF
SNOWFALL...MAINLY DUE TO THE GFS SHOWING A TROUGH MOVING THROUGH
THE NORTHLAND. IT LOOKS LIKE A RIDGE WILL MOVE INTO THE REGION
FRIDAY NIGHT WITH SOUTHERLY WINDS DEVELOPING BY SATURDAY MORNING.
SATURDAY...IT LOOKS LIKE A RELATIVELY WARM DAY. SOUTHWESTERLY WINDS
WILL DEVELOP AS A LOW PRESSURE SYSTEM MOVES FROM CENTRAL MANITOBA TO
WESTERN ONTARIO. THERE MAY BE SOME LIGHT PCPN ACROSS THE NORTHLAND.
CONSIDERING THE WARMER SURFACE TEMPERATURES AND TEMPERATURES
ALOFT...FORECASTED A POSSIBLE MIXTURE OF RAIN AND SNOW. PLUS...MODEL
SOUNDINGS GENERALLY HAD SATURATION ALOFT TO ONLY ABOUT -5 DEGREES
CELSIUS OR LESS UNTIL LATER IN THE EVENING WHEN THE COLDER AIR IS
USHERED INTO THE NORTHLAND. SO WOULD THINK THE PCPN WOULD LIKELY
TURN BACK TO SNOW SATURDAY NIGHT.
SUNDAY AND MONDAY...THE BEGINNING OF NEXT WEEK SHOULD START OFF
COLD. IT LOOKS LIKE THE POSSIBILITY OF LINGERING SYNOPTIC SNOW
ACROSS THE NORTHLAND...AS WELL AS LAKE EFFECT SNOWFALL ALONG PARTS
OF THE SOUTH SHORE. THE MODELS INDICATE VERY COLD 850 HPA WILL WRAP
INTO THE NORTHLAND...AS LOW AS -16 DEGREES CELSIUS. THIS SHOULD MAKE
FOR A SOLID TEMPERATURE DIFFERENCE BETWEEN 850 HPA AND THE LAKE
SURFACE TEMPERATURE...WHICH IS AROUND 4 DEGREES CELSIUS.
&&
.POINT TEMPS/POPS...
DLH 27 19 29 21 / 30 70 20 20
INL 26 12 26 15 / 30 30 10 20
BRD 32 25 33 24 / 10 60 20 30
HYR 28 20 32 23 / 30 70 30 30
ASX 29 20 33 24 / 20 70 30 20
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
AVIATION...BERDES
AREA FORECAST DISCUSSION...UPDATED
NWS DULUTH MN
1211 PM CST WED DEC 28 2011
.UPDATE...
SNOW AREA SPREADING EAST AS FORECAST AND HAVE UPDATED THE FORECAST
TO TAKE OUT THE SNOW FROM THE AREA WEST OF A LINE FROM INL THROUGH
DLH. SATELLITE SHOWS CLEAR SKIES BEHIND THE SNOW...BUT AREA OF LOW
CLOUDS WILL SPREAD SOUTH INTO NORTHERN MN....WHILE WAA SLOUDS WILL
MOVE IN THR THE WEST LATE THIS AFTERNOON.
&&
PREV DISCUSSION... /ISSUED 356 AM CST WED DEC 28 2011/
SHORT TERM...THE MAIN FORECAST CONCERN IN THE SHORT TERM IS THE
AMOUNT AND LOCATION OF ACCUMULATING SNOWFALL TODAY THROUGH TONIGHT.
AT 330 AM...CLOUDS WERE INCREASING AHEAD OF A WEAK SHORTWAVE AND
UP[PER LEVEL JET MAX TRAVERSING ACROSS MN. STRONG LOW LEVEL WAA
AND THETA-E ADVECTION WAS HELPING TO GENERATE LIGHT SNOW ACROSS
WESTERN MN DESPITE INITIALLY DRY LOW LEVEL AIR. THE HRRR RAPID
REFRESH WAS DEPICTING THE AREA OF CLOUDS/LIGHT SNOW FAIRLY WELL.
THE SHORTWAVE AND 100+ KNOT UPPER LEVEL JET MAX WILL CONTINUE TO
PUSH ACROSS THE NORTHLAND TODAY...PUSHING INTO THE WESTERN GREAT
LAKES BY THIS AFTERNOON. THE LATEST HRRR ACTUALLY SHOWS THE
RETURNS DIMINISHING FOR A TIME THIS EARLY MORNING...BEFORE
INCREASING A BIT AGAIN AS THEY REACH NE MN LATER IN THE MORNING.
THINK THERE IS A CHANCE FOR ABOUT A HALF INCH OF SNOWFALL IN SPOTS
TODAY. COULD SEE A BIT MORE ALONG THE SAWTOOTH MOUNTAINS OF THE
NORTH SHORE...AS WINDS COME AROUND TO THE EAST AND SUPPORT LAKE
EFFECT SNOW SHOWERS.
A STRONGER SYSTEM WILL MOVE IN TONIGHT...AND QUICKLY EXIT THE
REGION ON THURSDAY. HAVE SHIFTED THE FOCUS FOR ACCUMULATING
SNOWFALL A BIT TO THE SOUTH BASED ON THE LATEST 00Z MODEL RUNS.
CURRENT THINKING IS THAT THERE WILL BE A STRIPE OF 1 TO 3 INCHES
FROM THE NORTHERN BRAINERD LAKES REGION...THROUGH THE TWIN PORTS
AND INTO NW WI. ALSO CANNOT RULE OUT A NARROW STRIPE OF 2 TO 4
INCHES OR POSSIBLY A BIT MORE AS THE SYSTEM DROPS TO THE SOUTHEAST
AND LAYS DOWN A SWATH OF ACCUMULATING SNOWFALL. THE NORTH SHORE
SHOULD ALSO SEE HIGHER AMOUNTS DUE TO LAKE EFFECT/LAKE
ENHANCEMENT. IN TERMS OF SURFACE LOW PRESSURE...THE MODELS ARE
FAIRLY SIMILAR...BUT QPF AMOUNTS AND LOCATION DO VARY BETWEEN THE
ECMWF/NAM/GFS AND GEM. WILL TAKE A CONSENSUS SOLUTION. MAY NEED TO
BUMP UP AMOUNTS IN LATER FORECAST PACKAGES. IN THE
GRIDS...CURRENTLY HAVE AMOUNTS SIMILAR TO WHAT IS MENTIONED ABOVE.
THINK THE SYSTEM WILL BE FAIRLY EFFICIENT AT RINGING OUT AVAILABLE
MOISTURE.
THE LOW PRESSURE SYSTEM WILL MOVE OUT OF THE REGION ON
THURSDAY...WITH A BIT OF A BREAK BEFORE THE NEXT SYSTEM ARRIVES
THURSDAY NIGHT. THE NAM SOLUTION WOULD SUPPORT HIGHER POPS FOR
THURSDAY NIGHT...BUT THE ECMWF/GFS KEEP THE ACCUMULATING SNOW
GENERALLY WEST AND SOUTH OF THE CWA.
LONG TERM...FRIDAY THROUGH TUESDAY.
FRIDAY...THE LONG TERM PERIOD BEGINS WITH LOW CHANCES OF
SNOWFALL...MAINLY DUE TO THE GFS SHOWING A TROUGH MOVING THROUGH
THE NORTHLAND. IT LOOKS LIKE A RIDGE WILL MOVE INTO THE REGION
FRIDAY NIGHT WITH SOUTHERLY WINDS DEVELOPING BY SATURDAY MORNING.
SATURDAY...IT LOOKS LIKE A RELATIVELY WARM DAY. SOUTHWESTERLY WINDS
WILL DEVELOP AS A LOW PRESSURE SYSTEM MOVES FROM CENTRAL MANITOBA TO
WESTERN ONTARIO. THERE MAY BE SOME LIGHT PCPN ACROSS THE NORTHLAND.
CONSIDERING THE WARMER SURFACE TEMPERATURES AND TEMPERATURES
ALOFT...FORECASTED A POSSIBLE MIXTURE OF RAIN AND SNOW. PLUS...MODEL
SOUNDINGS GENERALLY HAD SATURATION ALOFT TO ONLY ABOUT -5 DEGREES
CELSIUS OR LESS UNTIL LATER IN THE EVENING WHEN THE COLDER AIR IS
USHERED INTO THE NORTHLAND. SO WOULD THINK THE PCPN WOULD LIKELY
TURN BACK TO SNOW SATURDAY NIGHT.
SUNDAY AND MONDAY...THE BEGINNING OF NEXT WEEK SHOULD START OFF
COLD. IT LOOKS LIKE THE POSSIBILITY OF LINGERING SYNOPTIC SNOW
ACROSS THE NORTHLAND...AS WELL AS LAKE EFFECT SNOWFALL ALONG PARTS
OF THE SOUTH SHORE. THE MODELS INDICATE VERY COLD 850 HPA WILL WRAP
INTO THE NORTHLAND...AS LOW AS -16 DEGREES CELSIUS. THIS SHOULD MAKE
FOR A SOLID TEMPERATURE DIFFERENCE BETWEEN 850 HPA AND THE LAKE
SURFACE TEMPERATURE...WHICH IS AROUND 4 DEGREES CELSIUS.
&&
.POINT TEMPS/POPS...
DLH 27 19 29 21 / 30 70 20 20
INL 26 12 26 15 / 30 30 10 20
BRD 32 25 33 24 / 10 60 20 30
HYR 28 20 32 23 / 30 70 30 30
ASX 29 20 33 24 / 20 70 30 20
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
SHORT TERM...CLC
LONG TERM....BERDES
AREA FORECAST DISCUSSION
NWS DULUTH MN
553 AM CST WED DEC 28 2011
.AVIATION [12Z TAF ISSUANCE]...
A SHORTWAVE MOVING THROUGH MANITOBA AND THE NORTHERN PLAINS WILL
BRING BKN/OVC MVFR CEILINGS TO NORTHEASTERN MINNESOTA AND
NORTHWESTERN WISCONSIN THIS MORNING. THERE WILL BE A BRIEF THREE TO
FOUR HOUR PERIOD OF LIGHT SNOWFALL WITH THIS SHORTWAVE PASSAGE.
THERE MAY BE PERIODS OF MVFR VIS WITH THE SNOW. MVFR OR LOW END VFR
CIGS WILL LIKELY REMAIN THROUGH THIS AFTERNOON...BUT THERE IS A
CHANCE OF SOME CLEARING. A CANADIAN CLIPPER WILL SWING THROUGH
CENTRAL MINNESOTA TONIGHT. IT WILL PROLONG MVFR CIGS THROUGH TONIGHT
AND BRING MORE LIGHT SNOW. MVFR VSBYS ARE POSSIBLE WITH THE SNOW.
LIGHT WINDS ARE EXPECTED THROUGH TOMORROW MORNING.
&&
.PREV DISCUSSION... /ISSUED 356 AM CST WED DEC 28 2011/
SHORT TERM...THE MAIN FORECAST CONCERN IN THE SHORT TERM IS THE
AMOUNT AND LOCATION OF ACCUMULATING SNOWFALL TODAY THROUGH TONIGHT.
AT 330 AM...CLOUDS WERE INCREASING AHEAD OF A WEAK SHORTWAVE AND
UP[PER LEVEL JET MAX TRAVERSING ACROSS MN. STRONG LOW LEVEL WAA
AND THETA-E ADVECTION WAS HELPING TO GENERATE LIGHT SNOW ACROSS
WESTERN MN DESPITE INITIALLY DRY LOW LEVEL AIR. THE HRRR RAPID
REFRESH WAS DEPICTING THE AREA OF CLOUDS/LIGHT SNOW FAIRLY WELL.
THE SHORTWAVE AND 100+ KNOT UPPER LEVEL JET MAX WILL CONTINUE TO
PUSH ACROSS THE NORTHLAND TODAY...PUSHING INTO THE WESTERN GREAT
LAKES BY THIS AFTERNOON. THE LATEST HRRR ACTUALLY SHOWS THE
RETURNS DIMINISHING FOR A TIME THIS EARLY MORNING...BEFORE
INCREASING A BIT AGAIN AS THEY REACH NE MN LATER IN THE MORNING.
THINK THERE IS A CHANCE FOR ABOUT A HALF INCH OF SNOWFALL IN SPOTS
TODAY. COULD SEE A BIT MORE ALONG THE SAWTOOTH MOUNTAINS OF THE
NORTH SHORE...AS WINDS COME AROUND TO THE EAST AND SUPPORT LAKE
EFFECT SNOW SHOWERS.
A STRONGER SYSTEM WILL MOVE IN TONIGHT...AND QUICKLY EXIT THE
REGION ON THURSDAY. HAVE SHIFTED THE FOCUS FOR ACCUMULATING
SNOWFALL A BIT TO THE SOUTH BASED ON THE LATEST 00Z MODEL RUNS.
CURRENT THINKING IS THAT THERE WILL BE A STRIPE OF 1 TO 3 INCHES
FROM THE NORTHERN BRAINERD LAKES REGION...THROUGH THE TWIN PORTS
AND INTO NW WI. ALSO CANNOT RULE OUT A NARROW STRIPE OF 2 TO 4
INCHES OR POSSIBLY A BIT MORE AS THE SYSTEM DROPS TO THE SOUTHEAST
AND LAYS DOWN A SWATH OF ACCUMULATING SNOWFALL. THE NORTH SHORE
SHOULD ALSO SEE HIGHER AMOUNTS DUE TO LAKE EFFECT/LAKE
ENHANCEMENT. IN TERMS OF SURFACE LOW PRESSURE...THE MODELS ARE
FAIRLY SIMILAR...BUT QPF AMOUNTS AND LOCATION DO VARY BETWEEN THE
ECMWF/NAM/GFS AND GEM. WILL TAKE A CONSENSUS SOLUTION. MAY NEED TO
BUMP UP AMOUNTS IN LATER FORECAST PACKAGES. IN THE
GRIDS...CURRENTLY HAVE AMOUNTS SIMILAR TO WHAT IS MENTIONED ABOVE.
THINK THE SYSTEM WILL BE FAIRLY EFFICIENT AT RINGING OUT AVAILABLE
MOISTURE.
THE LOW PRESSURE SYSTEM WILL MOVE OUT OF THE REGION ON
THURSDAY...WITH A BIT OF A BREAK BEFORE THE NEXT SYSTEM ARRIVES
THURSDAY NIGHT. THE NAM SOLUTION WOULD SUPPORT HIGHER POPS FOR
THURSDAY NIGHT...BUT THE ECMWF/GFS KEEP THE ACCUMULATING SNOW
GENERALLY WEST AND SOUTH OF THE CWA.
LONG TERM...FRIDAY THROUGH TUESDAY.
FRIDAY...THE LONG TERM PERIOD BEGINS WITH LOW CHANCES OF
SNOWFALL...MAINLY DUE TO THE GFS SHOWING A TROUGH MOVING THROUGH
THE NORTHLAND. IT LOOKS LIKE A RIDGE WILL MOVE INTO THE REGION
FRIDAY NIGHT WITH SOUTHERLY WINDS DEVELOPING BY SATURDAY MORNING.
SATURDAY...IT LOOKS LIKE A RELATIVELY WARM DAY. SOUTHWESTERLY WINDS
WILL DEVELOP AS A LOW PRESSURE SYSTEM MOVES FROM CENTRAL MANITOBA TO
WESTERN ONTARIO. THERE MAY BE SOME LIGHT PCPN ACROSS THE NORTHLAND.
CONSIDERING THE WARMER SURFACE TEMPERATURES AND TEMPERATURES
ALOFT...FORECASTED A POSSIBLE MIXTURE OF RAIN AND SNOW. PLUS...MODEL
SOUNDINGS GENERALLY HAD SATURATION ALOFT TO ONLY ABOUT -5 DEGREES
CELSIUS OR LESS UNTIL LATER IN THE EVENING WHEN THE COLDER AIR IS
USHERED INTO THE NORTHLAND. SO WOULD THINK THE PCPN WOULD LIKELY
TURN BACK TO SNOW SATURDAY NIGHT.
SUNDAY AND MONDAY...THE BEGINNING OF NEXT WEEK SHOULD START OFF
COLD. IT LOOKS LIKE THE POSSIBILITY OF LINGERING SYNOPTIC SNOW
ACROSS THE NORTHLAND...AS WELL AS LAKE EFFECT SNOWFALL ALONG PARTS
OF THE SOUTH SHORE. THE MODELS INDICATE VERY COLD 850 HPA WILL WRAP
INTO THE NORTHLAND...AS LOW AS -16 DEGREES CELSIUS. THIS SHOULD MAKE
FOR A SOLID TEMPERATURE DIFFERENCE BETWEEN 850 HPA AND THE LAKE
SURFACE TEMPERATURE...WHICH IS AROUND 4 DEGREES CELSIUS.
&&
.POINT TEMPS/POPS...
DLH 27 19 29 21 / 30 70 20 20
INL 26 12 26 15 / 30 30 10 20
BRD 32 25 33 24 / 20 60 20 30
HYR 28 20 32 23 / 20 70 30 30
ASX 29 20 33 24 / 20 70 30 20
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
AVIATION...GROCHOCINSKI
AREA FORECAST DISCUSSION
NWS DULUTH MN
356 AM CST WED DEC 28 2011
.SHORT TERM...THE MAIN FORECAST CONCERN IN THE SHORT TERM IS THE
AMOUNT AND LOCATION OF ACCUMULATING SNOWFALL TODAY THROUGH TONIGHT.
AT 330 AM...CLOUDS WERE INCREASING AHEAD OF A WEAK SHORTWAVE AND
UP[PER LEVEL JET MAX TRAVERSING ACROSS MN. STRONG LOW LEVEL WAA
AND THETA-E ADVECTION WAS HELPING TO GENERATE LIGHT SNOW ACROSS
WESTERN MN DESPITE INITIALLY DRY LOW LEVEL AIR. THE HRRR RAPID
REFRESH WAS DEPICTING THE AREA OF CLOUDS/LIGHT SNOW FAIRLY WELL.
THE SHORTWAVE AND 100+ KNOT UPPER LEVEL JET MAX WILL CONTINUE TO
PUSH ACROSS THE NORTHLAND TODAY...PUSHING INTO THE WESTERN GREAT
LAKES BY THIS AFTERNOON. THE LATEST HRRR ACTUALLY SHOWS THE
RETURNS DIMINISHING FOR A TIME THIS EARLY MORNING...BEFORE
INCREASING A BIT AGAIN AS THEY REACH NE MN LATER IN THE MORNING.
THINK THERE IS A CHANCE FOR ABOUT A HALF INCH OF SNOWFALL IN SPOTS
TODAY. COULD SEE A BIT MORE ALONG THE SAWTOOTH MOUNTAINS OF THE
NORTH SHORE...AS WINDS COME AROUND TO THE EAST AND SUPPORT LAKE
EFFECT SNOW SHOWERS.
A STRONGER SYSTEM WILL MOVE IN TONIGHT...AND QUICKLY EXIT THE
REGION ON THURSDAY. HAVE SHIFTED THE FOCUS FOR ACCUMULATING
SNOWFALL A BIT TO THE SOUTH BASED ON THE LATEST 00Z MODEL RUNS.
CURRENT THINKING IS THAT THERE WILL BE A STRIPE OF 1 TO 3 INCHES
FROM THE NORTHERN BRAINERD LAKES REGION...THROUGH THE TWIN PORTS
AND INTO NW WI. ALSO CANNOT RULE OUT A NARROW STRIPE OF 2 TO 4
INCHES OR POSSIBLY A BIT MORE AS THE SYSTEM DROPS TO THE SOUTHEAST
AND LAYS DOWN A SWATH OF ACCUMULATING SNOWFALL. THE NORTH SHORE
SHOULD ALSO SEE HIGHER AMOUNTS DUE TO LAKE EFFECT/LAKE
ENHANCEMENT. IN TERMS OF SURFACE LOW PRESSURE...THE MODELS ARE
FAIRLY SIMILAR...BUT QPF AMOUNTS AND LOCATION DO VARY BETWEEN THE
ECMWF/NAM/GFS AND GEM. WILL TAKE A CONSENSUS SOLUTION. MAY NEED TO
BUMP UP AMOUNTS IN LATER FORECAST PACKAGES. IN THE
GRIDS...CURRENTLY HAVE AMOUNTS SIMILAR TO WHAT IS MENTIONED ABOVE.
THINK THE SYSTEM WILL BE FAIRLY EFFICIENT AT RINGING OUT AVAILABLE
MOISTURE.
THE LOW PRESSURE SYSTEM WILL MOVE OUT OF THE REGION ON
THURSDAY...WITH A BIT OF A BREAK BEFORE THE NEXT SYSTEM ARRIVES
THURSDAY NIGHT. THE NAM SOLUTION WOULD SUPPORT HIGHER POPS FOR
THURSDAY NIGHT...BUT THE ECMWF/GFS KEEP THE ACCUMULATING SNOW
GENERALLY WEST AND SOUTH OF THE CWA.
.LONG TERM...FRIDAY THROUGH TUESDAY.
FRIDAY...THE LONG TERM PERIOD BEGINS WITH LOW CHANCES OF
SNOWFALL...MAINLY DUE TO THE GFS SHOWING A TROUGH MOVING THROUGH
THE NORTHLAND. IT LOOKS LIKE A RIDGE WILL MOVE INTO THE REGION
FRIDAY NIGHT WITH SOUTHERLY WINDS DEVELOPING BY SATURDAY MORNING.
SATURDAY...IT LOOKS LIKE A RELATIVELY WARM DAY. SOUTHWESTERLY WINDS
WILL DEVELOP AS A LOW PRESSURE SYSTEM MOVES FROM CENTRAL MANITOBA TO
WESTERN ONTARIO. THERE MAY BE SOME LIGHT PCPN ACROSS THE NORTHLAND.
CONSIDERING THE WARMER SURFACE TEMPERATURES AND TEMPERATURES
ALOFT...FORECASTED A POSSIBLE MIXTURE OF RAIN AND SNOW. PLUS...MODEL
SOUNDINGS GENERALLY HAD SATURATION ALOFT TO ONLY ABOUT -5 DEGREES
CELSIUS OR LESS UNTIL LATER IN THE EVENING WHEN THE COLDER AIR IS
USHERED INTO THE NORTHLAND. SO WOULD THINK THE PCPN WOULD LIKELY
TURN BACK TO SNOW SATURDAY NIGHT.
SUNDAY AND MONDAY...THE BEGINNING OF NEXT WEEK SHOULD START OFF
COLD. IT LOOKS LIKE THE POSSIBILITY OF LINGERING SYNOPTIC SNOW
ACROSS THE NORTHLAND...AS WELL AS LAKE EFFECT SNOWFALL ALONG PARTS
OF THE SOUTH SHORE. THE MODELS INDICATE VERY COLD 850 HPA WILL WRAP
INTO THE NORTHLAND...AS LOW AS -16 DEGREES CELSIUS. THIS SHOULD MAKE
FOR A SOLID TEMPERATURE DIFFERENCE BETWEEN 850 HPA AND THE LAKE
SURFACE TEMPERATURE...WHICH IS AROUND 4 DEGREES CELSIUS.
&&
.AVIATION.../06Z TAF ISSUANCE/
CURRENTLY VFR CONDITIONS WITH 10K FT CIGS MOVING IN FROM THE WEST
ASSOCIATED WITH AN UPPER S/W. REGIONAL RADAR IS INDICATING A FEW
-SHSN PUSHING INTO NW MN...AND THIS WILL EVENTUALLY MAKE IT TO
BRD BEFORE 12Z AND INL JUST AFTER 12Z. AN HOUR OR TWO LATER TO HIB
AND DLH BEFORE PASSING THROUGH HYR BY 16Z. SNOW SHOWERS WILL BE
VERY SHORT-LIVED WITH THIS FAST MOVING WAVE. CIGS AND VSBYS COULD
DROP TO MID/HIGH-END MVFR THIS MORNING...BUT SHOULD LIFT TO LOW-
END VFR BY THE AFTERNOON. LIGHT SW WINDS WILL VEER TO SOUTH AND
REMAIN LESS THAN 10 KTS OUT OF THE SOUTH THROUGH THIS EVENING. THE
NEXT WAVE QUICKLY MOVES IN FROM THE WEST WED EVENING WITH A BETTER
CHANCE OF MVFR CIGS/VSBYS BEGINNING JUST BEFORE 06Z.
&&
.POINT TEMPS/POPS...
DLH 27 19 29 21 / 30 70 20 20
INL 26 12 26 15 / 30 30 10 20
BRD 32 25 33 24 / 20 60 20 30
HYR 28 20 32 23 / 20 70 30 30
ASX 29 20 33 24 / 20 70 30 20
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
SHORT TERM...DAP
LONG TERM....GROCHOCINSKI
AVIATION...GROCHOCINSKI
AREA FORECAST DISCUSSION
NWS BILLINGS MT
950 AM MST WED DEC 28 2011
.SHORT TERM...VALID FOR TDY AND THU...
UPDATE TO MORNING FORECAST TO ISSUE HIGH WIND WARNING ACROSS
WESTERN COUNTIES...INCLUDING MUSSELSHELL...YELLOWSTONE...AND EAST
CARBON COUNTIES...AND AREAS WEST. WINDS ARE EXPECTED TO PICK UP
THIS AFTERNOON ACROSS THE WESTERN ZONES...WITH SUSTAINED WINDS
REACHING AROUND 40 MPH AND GUSTS APPROACHING 60 MPH. ALTHOUGH GFS
INDICATES AN INVERSION REMAINING IN PLACE ACROSS THE AREA...NAM
AND RUC MODELS BOTH INDICATE BREAK DOWN OF INVERSION THIS
AFTERNOON...WITH STEEP LAPSE RATES IN THE 1000-850MB
LEVEL...RANGING FROM 6 TO 9 C/KM. THIS SHOULD ALLOW FOR STRONG
WINDS ALOFT TO MIX DOWN TO THE SFC. WINDS ARE EXPECTED TO DROP OFF
THIS EVENING AFTER SUNSET...AS THE INVERSION REDEVELOPS. WINDS
WILL PICK UP AGAIN TOMORROW BY LATE MORNING/EARLY AFTERNOON...AND
ARE EXPECTED TO BE EVEN STRONGER THAN WINDS EXPERIENCED TODAY.
OTHERWISE OVERALL FORECAST APPEARS IN GOOD SHAPE. AAG
...PREVIOUS DISCUSSION...
VERY DYNAMIC PATTERN OVER OUR FORECAST AREA THE NEXT COUPLE OF
DAYS. MODELS GENERALLY IN GOOD AGREEMENT. MAIN FORECAST ISSUE
WILL BE WIND HIGHLIGHTS ACROSS THE PLAINS.
EARLY THIS MORNING RADAR TRENDS ALREADY INDICATED SOME LIGHT
PRECIP ACROSS THE NORTHERN AND CENTRAL ZONES EXTENDING FROM
SUMATRA SOUTH INTO BIG HORN COUNTY. SNOW WAS ALSO INDICATED IN
THE HIGH COUNTRY WHERE WEB CAMS SHOWED SNOW AT COOKE CITY. THIS
PRECIPITATION CAN BE ATTRIBUTED TO WARM AIR ADVECTION AT 700
MB...AND FAVORABLE JET DYNAMICS WHERE OUR REGION IS UNDER THE
INFLUENCE OF LEFT EXIT REGION. THIS IS BATTLING THE STRONG
DOWNSLOPE FLOW OFF THE HIGHER TERRAIN WHICH IS WHY LITTLE RADAR
RETURNS ARE OCCURRING IN THE FOOTHILLS. THE JET MAX ASSOCIATED
WITH THIS FORCING WILL SHIFT QUICKLY EAST BY MIDDAY BRINGING AN
END TO MUCH OF THE PRECIP...THOUGH SOME WARM AIR ADVECTION WILL
CONTINUE.
FAVORABLE PRESSURE GRADIENT WILL CONTINUE FOR THE LIVINGSTON AND
NYE AREAS TODAY. THUS WARNING FOR THESE AREAS LOOKS GOOD AS HYBRID
GAP FLOW AND MIX DOWN MAY RESULT IN GUSTS TO 75-80 MPH. THE
GRADIENT IS SOMEWHAT WEAKER TONIGHT AND NEW DATA SUGGEST QUITE A
BIT WEAKER THURSDAY.THEREFORE...WARNING FOR THESE AREAS THROUGH
TODAY LOOKS GOOD...BUT MAY NEED TO BE DROPPED EARLY IF MODEL
TRENDS CONTINUE TO INDICATE A WEAKENING GRADIENT TONIGHT AND
THURSDAY. WILL LET THE DAY SHIFT TAKE ANOTHER LOOK AT THIS.
AS FOR HIGH WINDS ON THE PLAINS...THE WARM AIR COMING IN AT THE
700MB LEVEL WILL TEND TO LIMIT POTENTIAL MIX DOWN OF STRONG WINDS
TODAY TO AT LEAST SOME EXTENT. HOWEVER...WITH 40 TO 50 KNOT WINDS
ONLY 1200-1500 FEET OFF THE GROUND WILL CONTINUE TO RIDE THE HIGH
WIND WATCH FOR MUCH OF THE AREA.
TONIGHT...WE MAY SEE A STRONG...THOUGH BRIEF...BAROCLINIC BAND SET
UP OVER OUR CENTRAL ZONES FROM ROUNDUP TO BROADUS DUE TO WARM AIR
ADVECTION TO THE WEST AND COLD ADVECTION COMING IN FROM THE
NORTHWEST OVER NORTHEAST MONTANA. CROSS SECTIONS ALSO A PERIOD OF
HEAVY SNOW POSSIBLE OVER THE WEST FACING SLOPES IN THE HIGH
COUNTRY. OTHERWISE DOWNSLOPE WILL REMAIN A FACTOR FOR MANY AREAS
NEAR THE MOUNTAINS AND FOOTHILLS.
THURSDAY...140 KT JET MAX NOSES INTO THE REGION RIGHT OVER
SOUTHERN MONTANA. ASSOCIATED FORCING WILL PRODUCE A SLIGHT CHANCE
OF PRECIP AT THE LOWER ELEVATIONS. HOWEVER THE MAIN THREAT WILL BE
WIND ON THURSDAY. STRONG COLD AIR ADVECTION WILL SPREAD INTO THE
AREA FROM THE NORTHWEST AT 700 MB. THIS WILL ALLOW A BETTER
OPPORTUNITY TO MIX DOWN THE STRONG WINDS ALOFT AS LAPSE RATES WILL
BE TWICE WHAT THEY ARE TODAY IN THE LOWER LEVELS. HAVE ADDED THE
EASTERN ZONES TO THE HIGH WIND WATCH FOR THURSDAY AS THE STRONGEST
WINDS AND STEEPEST PROGGED LAPSE RATES AFFECT THESE ZONES WITH 850
MB WINDS 55 TO 60 KTS. EXPECT WINDS TO QUICKLY SUBSIDE AFTER DARK
THURSDAY EVENING. BT
.LONG TERM...VALID FOR FRI...SAT...SUN...MON...TUE...
EXTENDED FORECAST CONTINUES TO LOOK WINDY AND MILD OVERALL WITH
MODELS BEING IN GOOD AGREEMENT UNTIL THE MIDDLE OF NEXT WEEK.
RIDGE OF HIGH PRESSURE WILL BE OVER THE STATE FRIDAY ALONG WITH A
STRONG LEE-SIDE TROUGH. THIS WILL BRING VERY WINDY CONDITIONS
ACROSS THE ENTIRE FORECAST AREA WITH MILD TEMPERATURES. MODELS
BRING A STRONG TROUGH AND COLD FRONT ACROSS THE FORECAST AREA
SATURDAY BRINGING A CHANCE OF RAIN AND SNOW SHOWERS TO THE PLAINS
WITH VERY WINDY CONDITIONS POSSIBLE. WINDS WILL SUBSIDE ON SUNDAY
WITH TEMPERATURES RETURNING BACK TO NORMAL LEVELS FOR THIS TIME
OF YEAR. RIDGING THEN BEGINS TO BUILD BACK ONCE AGAIN SUNDAY
NIGHT INTO MONDAY BRINGING CONTINUED DRY CONDITIONS AND A RETURN
TO ABOVE NORMAL TEMPERATURES. IN GENERAL FOR MONDAY INTO THE
MIDDLE OF NEXT WEEK...A FAST FLOW ALOFT WILL CONTINUE WITH
ALTERNATING RIDGING AND TROUGHING AS SEVERAL SYSTEMS MOVE OVER
THE FORECAST AREA. LEE-SIDE TROUGHING WILL BE IN PLACE AT TIMES
AS WELL RESULTING IN PERIODS OF STRONG GUSTY WINDS. HOOLEY
&&
.AVIATION...
STRONG AND GUSTY WINDS WILL CONTINUE FROM BIG TIMBER TO KLVM AND
THE ADJACENT FOOTHILLS TODAY. GUSTS OVER 65 KNOTS WILL BE LIKELY
ACROSS THESE AREAS. STRONG AND GUSTY WINDS ARE ALSO EXPECTED TO
SPREAD EASTWARD TO KBIL THIS AFTERNOON WITH GUSTS AROUND 55 KTS.
SNOW WILL IMPACT AREA MOUNTAINS TODAY AND TONIGHT. MOUNTAINS
OBSCURATIONS CAN BE EXPECTED. VFR CONDITIONS CAN BE EXPECTED OVER
THE PLAINS. RICHMOND
&&
.PRELIMINARY POINT TEMP/POPS...
TDY THU FRI SAT SUN MON TUE
-------------------------------------------------------
BIL 053 036/053 030/049 032/043 023/037 023/045 029/044
3/W 42/W 22/W 21/N 10/B 00/B 00/B
LVM 050 040/049 033/049 034/039 019/036 022/044 032/043
2/J 44/W 23/W 21/N 10/B 00/B 00/B
HDN 058 032/057 026/053 026/044 019/037 018/047 025/046
3/W 43/W 21/B 21/N 00/B 00/U 00/B
MLS 054 032/053 027/049 029/041 020/036 018/044 025/045
4/W 23/W 11/B 11/N 00/B 00/U 00/B
4BQ 054 031/054 026/050 027/043 020/038 018/046 024/047
3/W 23/W 21/B 21/N 10/B 00/U 00/U
BHK 050 029/049 025/046 031/038 017/032 016/041 025/042
2/W 23/W 11/B 11/N 10/B 00/U 00/U
SHR 048 027/048 024/046 030/041 016/035 015/042 023/043
2/W 23/W 21/B 22/J 10/B 00/B 00/B
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...HIGH WIND WARNING IN EFFECT UNTIL 8 PM MST THIS EVENING FOR
ZONES 28-29-34-35-39-41-42.
HIGH WIND WATCH IN EFFECT FROM THURSDAY MORNING THROUGH
THURSDAY AFTERNOON FOR ZONES 28>39-41-42-57-58.
HIGH WIND WARNING IN EFFECT UNTIL 11 AM MST FRIDAY FOR ZONES
65-66.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
518 PM CST THU DEC 29 2011
.UPDATE...
.AVIATION...
VFR IS EXPECTED ALL AREAS TONIGHT AND FRIDAY.
SCATTERED SHOWERS LOWERING CIGS TO OVC040 ARE EXPECTED TO EXIT THE
FORECAST AREA BY 06Z THIS EVENING. WIND GUSTS TO 35 MPH OR HIGHER SHOULD
BECOME LESS FREQUENT THIS EVENING. THEREAFTER...SCATTERED TO
BROKEN HIGH CLOUDINESS.
&&
.PREV DISCUSSION... /ISSUED 326 PM CST THU DEC 29 2011/
UPDATE...
AVIATION...
MID AND HIGH LEVEL CLOUDS WILL CONTINUE ACROSS WESTERN
AND NORTH CENTRAL NEBRASKA THIS AFTERNOON...WITH SKIES CLEARING
TONIGHT. CEILINGS MAY GET AS LOW AS 5000 FT AGL...ALONG WITH SCT
RAIN SHOWERS AND A FEW THUNDERSTORMS LATE THIS AFTERNOON AND EARLY
THIS EVENING. OVERALL VFR EXPECTED TO PREVAIL...WITH GUSTY WEST
WINDS TO 40 KTS WEST OF HIGHWAY 183 FROM LATE AFTERNOON THROUGH THE
EVENING. LOCAL GUSTS TO 50 KTS ARE POSSIBLE INVOF SHOWERS/STORMS.
PREV DISCUSSION... /ISSUED 321 PM CST THU DEC 29 2011/
DISCUSSION...
SHORT TERM...
WIND ADVISORY CONDITIONS ARE SPREADING THROUGH ALL OF THE WRN NEB
PANHANDLE THIS AFTERNOON. THERE IS THE POTENTIAL FOR STRONG WINDS
TO SPREAD THROUGH ALL OF THE PANHANDLE UNTIL 23Z. THEREAFTER THE
LOSS OF DAYTIME HEATING SHOULD CAUSE A DROP IN GUSTS. 30 MPH
SUSTAINED CONDITIONS MIGHT CONTINUE THIS EVENING AS LOW PRESSURE
TRACKS THROUGH THE MISSOURI BASIN. THE RUC SHOWS A PRONOUNCED TROP
FOLD ON THE PV15 SURFACE WHICH SHOULD MOVE THRU THE FCST AREA THIS
EVENING. THUS THE WIND ADZY WILL CONTINUE ACROSS GARDEN AND DEUEL
COUNTIES WITH A POSSIBLE NORTH AND EAST EXPANSION AS CONDITIONS
WARRANT. SCATTERED SHOWERS ISOLATED THUNDERSTORMS ARE EXPECTED TO CONTINUE
TRACKING THRU NRN NEB THIS EVENING.
THE STRONG WEST WINDS ARE BEING USHERED IN AHEAD OF A PACIFIC COLD
FRONT WORKING THRU NERN WY. THE FRONT SHOULD COOL TEMPS OFF
SOMEWHAT FOR FRIDAY WITH HIGHS ABOUT 10F COOLER THAN TODAY.
ANOTHER STRONG COLD FRONT IS EXPECTED TO MOVE THROUGH SATURDAY
MORNING...EARLY AFTERNOON. THIS FRONT IN COMBINATION WITH
DEEPENING LOW PRESSURE ACROSS THE UPPER MIDWEST AND VERY STRONG
PACIFIC HIGH PRESSURE SHOULD PRODUCE WIND ADVISORY CONDITIONS
ACROSS MOST AND POSSIBLY ALL OF THE FCST AREA. A BLEND OF MODEL
DATA AND GUIDANCE WAS USED FOR THE FCST WHICH PRODUCED HIGH END
WIND ADVISORY CONDITIONS ACROSS SWRN NEB.
AMPLE MOISTURE WILL BE PRESENT ALONG AND BEHIND THE FRONT SATURDAY
FOR SCATTERED RAIN AND SNOW SHOWERS...MAINLY ACROSS THE NORTH.
ANOTHER STRONG TROP FOLD WILL SWEEP THE FCST AREA IN CONCERT WITH
THE FRONTAL PASSAGE. THE GFS WAS OVERPOWERING WITH THE WIND
STRENGTH AND COLD AIR PRODUCING ALL SNOW WHILE THE NAM SHOWED A
MIX WITH WEAKER WINDS. THE WARMER NAM WAS PREFERRED.
PACIFIC HIGH PRESSURE WILL BUILD ACROSS THE FCST AREA SUNDAY
PRODUCING HIGHS IN THE UPPER 30S TO AROUND 40 WITH NEARLY CLEAR SKIES.
LONG TERM...
A RIDGE OF HIGH PRESSURE ALOFT WILL BE AMPLIFYING MONDAY ACROSS THE
ROCKIES...WHILE A TROUGH OF LOW PRESSURE CONTINUES IT/S EASTWARD
PROGRESSION INTO THE NORTHEAST STATES. OUR AREA WILL BE IN BETWEEN
THESE TWO FEATURES...WITH A BROAD NORTHWEST FLOW ALOFT. 850 MB
TEMPERATURES WILL BEGIN TO RECOVER MONDAY...AND CONTINUE TO WARM
THOUGH THURSDAY. IN FACT BY THURSDAY MODELS ARE SUGGESTING +15C OVER
THE AREA...WHICH WOULD PUT HIGH TEMPERATURES INTO POSSIBLE RECORD
TERRITORY. SO AFTER A COOL START MONDAY...HIGHS MID 30S TO MID
40S...TUESDAY THROUGH THURSDAY LOOKING VERY MILD. COULD BE PUSHING
60 DEGREES OR WARMER AGAIN BY THURSDAY.
AVIATION...
MID AND HIGH LEVEL CLOUDS WILL CONTINUE ACROSS WESTERN
AND NORTH CENTRAL NEBRASKA THIS AFTERNOON...WITH SKIES CLEARING
TONIGHT. CEILINGS MAY GET AS LOW AS 5000 FT AGL...ALONG WITH A FEW
RAIN SHOWERS...ACROSS NORTH CENTRAL NEBRASKA LATE THIS AFTERNOON AND
EARLY THIS EVENING. VFR EXPECTED TO PREVAIL...WITH GUSTY WEST
WINDS TO 30 KTS WEST OF HIGHWAY 83 FROM LATE AFTERNOON THROUGH THE
EVENING.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...WIND ADVISORY UNTIL 11 PM MST THIS EVENING FOR NEZ022-056.
&&
$$
SHORT TERM/EXTENDED...CDC
AVIATION...CDC
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
700 AM EST WED DEC 28 2011
.SYNOPSIS...
HIGH PRESSURE WILL BUILD INTO THE REGION TODAY AND LINGER THROUGH
FRIDAY. A COLD FRONT WILL PUSH THROUGH THE AREA FRIDAY NIGHT.
ANOTHER AREA OF HIGH PRESSURE WILL BUILD IN THIS WEEKEND. A STRONG
COLD FRONT WILL PUSH THROUGH SUNDAY NIGHT OR EARLY MONDAY OF NEXT
WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 7 AM WED...CURRENT H20 VAPOR ANALYSIS INDICATING H7 TROUGH
AXIS SWINGING THROUGH E NC AND COASTAL WATERS. CAA CONTINUES TO
KEEP WINDS IN THE 10 TO 15 KT RANGE AT THE SFC EARLY THIS MORNING.
RUC ANALYSIS INDICATES LARGEST PRES RISES CONTINUING THROUGH MID
MORNING TODAY...WHICH IN CONJUNCTION WITH EFFICIENT UNIDIRECTIONAL
SHEAR IN THE BL WILL BRING DOWN HIGHER WINDS ALOFT IN THE FORM OF
GUSTS IN THE 20 TO 25 KT RANGE AT THE SFC. GRADIENT WILL REMAIN
STRONGEST ACROSS THE OBX AND WITH GOOD MIXING...WILL LEAVE THE
CURRENT WIND ADVISORY IN EFFECT...THOUGH CRITERIA WILL BE
MARGINAL. GRADIENT RELAXES BY THIS AFTERNOON AND WINDS WILL
DIMINISH IN RESPONSE.
FOR TEMP FCST...USED MODEL BLEND OF THE BIAS CORRECTED GFS/SREF
GRIDS AND 1000-850 MB THICKNESSES TO YIELD HIGHS GENERALLY IN THE
LOWER 50S ACROSS E NC. IT WILL FEEL QUITE A BIT COOLER DUE TO THE
BRISK WESTERLY WINDS HOWEVER. SKIES WILL BE MOSTLY SUNNY AS DEEP
LAYER DRYING CONTINUES THROUGH THE DAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM THURSDAY/...
AS OF 3 AM WED...GUSTY WINDS OF TODAY WILL DIMINISH QUITE RAPIDLY
TOWARDS SUNSET THIS EVENING AS PRES GRADIENT WEAKENS AND DRY HIGH
PRES BEGINS BUILDING IN FROM THE WEST. TD VALS WILL PLUMMET
THROUGH THE 20S AND WITH CLEAR SKIES AND CALM WINDS OVERNIGHT...
MIN TEMPS WILL FOLLOW SUIT AND SETTLE INTO THE 20S FOR AREAS AWAY
FROM THE IMMEDIATE COAST. NW WINDS WILL CONTINUE FOR THE OBX WITH
LOWS HERE IN THE 30S.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
AS OF 300 AM WED...NO SIGNIFICANT CHANGES TO PREVIOUS FCST DURING
PERIOD. MODELS IN DECENT AGREEMENT WITH NEAR ZONAL FLOW PATTERN INTO
EARLY NEXT WEEK...WITH STRONGEST NORTHERN STREAM SHRT WV MOVING
THROUGH SAT. GULFMEX WILL BE CUTOFF SO JUST A DRY FRONTAL PASSAGE
EXPECTED AT SFC WITH THIS SYSTEM. DID ADJUST TEMPS THU-FRI BASED ON
LATEST MOS GDNC BLEND.
MODELS CONTINUE TO INDICATE UPR TROFFING OVER ERN US MON INTO TUE.
00Z ECMWF MORE PROGRESSIVE THAN PREVIOUS RUNS WITH TROF...WITH SFC
LOW DEVELOPMENT FARTHER OFFSHORE MIDWEEK...BUT LIKELY OVERDONE WITH
DEPTH OF TROF PER EXTENDED PROG DISCUSSIONS. MODELS DO CONTINUE TO
INDICATE ENOUGH DYNAMICS WITH UPR SYSTEM TO KEEP 20 POPS FOR SUN
NIGHT AND MONDAY.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
SHORT TERM /TODAY AND TONIGHT/...
AS OF 7 AM WED...PRES RISES WILL BE GREATEST THROUGH THE MORNING
AND WITH GOOD MIXING TODAY...WILL SEE WINDS GUSTING INTO THE 20 TO
25 KT RANGE FOR ALL TERMINALS. SKIES WILL BE SUNNY AS DRY HIGH
PRES BUILDS IN. WINDS DIMINISH VERY QUICKLY TOWARDS SUNSET AS HIGH
BUILDS IN...GRADIENT RELAXES AND CAA SUBSIDES. DO NOT EXPECT FOG
OR BR AS BNDRY LAYER WILL BE QUITE DRY WITH TD VALS IN THE LOW TO
MID 20S OVERNIGHT...THOUGH TYPICAL LOCALES SUCH AS KPGV WILL HAVE
TO BE MONITORED FOR BR DEVELOPMENT.
LONG TERM /WEDNESDAY THROUGH SUNDAY/...
AS OF 300 AM WED...VFR THROUGH THE PERIOD. ISOLATED SHOWERS
POSSIBLE SUNDAY NIGHT WITH A STONGER UPR LEVEL TROF.
&&
.MARINE...
SHORT TERM /THROUGH TONIGHT/
AS OF 7 AM WED...CURRENT SFC OBS INDICATING MARGINAL GALE
CONDITIONS OCCURING OFF NC COAST. FRYING PAN BUOY GUSTING BETWEEN
35 AND 40 KT THROGUH THIS MORNING...AND A SHIP 30 MI SE CAPE
HATTERAS REPORTING SUSTAINED WINDS OF 30 KT. NEAR TERM GUIDANCE
INDICATES GREATEST ISALLOBARIC PRES RISES OCCURRING RIGHT NOW AS
TROUGH AXIS IS SWINGING THROUGH THE COASTAL WATERS. THIS IS IN
LINE WITH HRRR WINDS GUSTS APPROACHING GALE FORCE THROUGH ABOUT
THIS TIME. WINDS WILL OCCASIONALLY GUST TO GALE FORCE OVER EASTERN
PORTIONS OF PAMLICO SOUND AS WELL THROUGH MID MORNING. 700 MB
TROUGH AXIS WILL EXIT THE NC COASTAL WATERS THIS MORNING...AND
WITH DEPARTING THOUGH DEEPENING LOW ACROSS NEW ENGLAND...WINDS
WILL BEGIN TO ABATE. CAA HOWEVER WILL CONTINUE TO PRODUCE SCA WIND
GUSTS THROUGH MUCH OF TODAY...AND WILL HAVE TO REPLACE GALES WITH
SCA AFTER THEIR SCHEDULED EXPIRATION TIMES OF 15Z. SEAS WILL ALSO
REMAIN ABOVE 6 FT FOR THE REMAINDER OF TODAY...HIGHEST THROUGH
THIS MORNING.
LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 300 AM WED...BRIEF PERIOD OF LIGHTER WINDS AND SEAS THU
MORNING...THEN GRADIENT BETWEEN LOW PRESSURE MOVING ACROSS N OF AREA
AND HIGH PRESSURE TO S WILL PRODUCE INCREASING W TO SW WINDS THU
NIGHT INTO FRI NIGHT...WITH MARGINAL SCA CONDITIONS PSBL FOR OUTER
PORTIONS OF WATERS. WINDS BECOMING NRLY LATE SAT FOLLOWING DRY
FRONTAL PASSAGE...WITH SPEEDS DECREASING SAT NIGHT WITH HIGH PRES
BUILDING IN FROM W. WINDS WILL VEER QUICKLY BACK TO SW SUN AS HIGH
PRES MOVES OFFSHORE. BLEND OF WW3...LOCAL SWAN AND PREVIOUS FCST
USED FOR SEAS.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...WIND ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR NCZ103-104.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR AMZ130-
135.
GALE WARNING UNTIL 10 AM EST THIS MORNING FOR AMZ150-152-154-
156-158.
&&
$$
SYNOPSIS...TL
NEAR TERM...TL
SHORT TERM...TL
LONG TERM...JBM
AVIATION...TL/JBM
MARINE...TL/JBM
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
337 AM EST WED DEC 28 2011
.SYNOPSIS...
HIGH PRESSURE WILL BUILD INTO THE REGION TODAY AND LINGER THROUGH
FRIDAY. A COLD FRONT WILL PUSH THROUGH THE AREA FRIDAY NIGHT.
ANOTHER AREA OF HIGH PRESSURE WILL BUILD IN THIS WEEKEND. A STRONG
COLD FRONT WILL PUSH THROUGH SUNDAY NIGHT OR EARLY MONDAY OF NEXT
WEEK.
&&
.NEAR TERM /TODAY/...
AS OF 3 AM WED...CURRENT H20 VAPOR ANALYSIS INDICATING H7 TROUGH
AXIS SWINGING THROUGH CENTRAL NC ATTM. MODEST CAA CONTINUES TO
KEEP WINDS IN THE 10 TO 15 KT RANGE AT THE SFC EARLY THIS MORNING.
RUC ANALYSIS INDICATES LARGEST PRES RISES CONTINUING THROUGH LATE
MORNING TODAY...WHICH IN CONJUNCTION WITH EFFICIENT UNIDIRECTIONAL
SHEAR IN THE BL WILL BRING DOWN WINDS ALOFT IN THE FORM OF GUSTS
IN THE 20 TO 25 KT RANGE AT THE SFC. GRADIENT WILL REMAIN
STRONGEST ACROSS THE OBX AND WITH GOOD MIXING...WILL LEAVE THE
CURRENT WIND ADVISORY IN EFFECT...THOUGH CRITERIA WILL BE
MARGINAL. GRADIENT RELAXES THIS AFTERNOON AND WINDS WILL DIMINISH
IN RESPONSE.
FOR TEMP FCST...USED MODEL BLEND OF THE BIAS CORRECTED GFS/SREF
GRIDS AND 1000-850 MB THICKNESSES TO YIELD HIGHS GENERALLY IN THE
LOWER 50S ACROSS E NC. IT WILL FEEL QUITE A BIT COOLER DUE TO THE
BRISK WESTERLY WINDS HOWEVER. SKIES WILL BE MOSTLY SUNNY AS DEEP
LAYER DRYING CONTINUES THROUGH THE DAY.
&&
.SHORT TERM /TONIGHT/...
AS OF 3 AM WED...GUSTY WINDS OF TODAY WILL DIMINISH QUITE RAPIDLY
TOWARDS SUNSET THIS EVENING AS PRES GRADIENT WEAKENS AND DRY HIGH
PRES BEGINS BUILDING IN FROM THE WEST. TD VALS WILL PLUMMET
THROUGH THE 20S AND WITH CLEAR SKIES AND CALM WINDS OVERNIGHT...
MIN TEMPS WILL FOLLOW SUIT AND SETTLE INTO THE 20S FOR AREAS AWAY
FROM THE IMMEDIATE COAST. NW WINDS WILL CONTINUE FOR THE OBX WITH
LOWS HERE IN THE 30S.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
AS OF 300 AM WED...NO SIGNIFICANT CHANGES TO PREVIOUS FCST DURING
PERIOD. MODELS IN DECENT AGREEMENT WITH NEAR ZONAL FLOW PATTERN INTO
EARLY NEXT WEEK...WITH STRONGEST NORTHERN STREAM SHRT WV MOVING
THROUGH SAT. GULFMEX WILL BE CUTOFF SO JUST A DRY FRONTAL PASSAGE
EXPECTED AT SFC WITH THIS SYSTEM. DID ADJUST TEMPS THU-FRI BASED ON
LATEST MOS GDNC BLEND.
MODELS CONTINUE TO INDICATE UPR TROFFING OVER ERN US MON INTO TUE.
00Z ECMWF MORE PROGRESSIVE THAN PREVIOUS RUNS WITH TROF...WITH SFC
LOW DEVELOPMENT FARTHER OFFSHORE MIDWEEK...BUT LIKELY OVERDONE WITH
DEPTH OF TROF PER EXTENDED PROG DISCUSSIONS. MODELS DO CONTINUE TO
INDICATE ENOUGH DYNAMICS WITH UPR SYSTEM TO KEEP 20 POPS FOR SUN
NIGHT AND MONDAY.
&&
.AVIATION /08Z WEDNESDAY THROUGH SUNDAY/...
SHORT TERM /TODAY AND TONIGHT/...
AS OF 3 AM WED...WEST WINDS BEHIND SFC FRONT WILL REMAIN QUITE
STRONG THROUGH EARLY THIS MORNING AS TIGHT GRAD REMAINS AND STRONG
CAA UNDERWAY. PRES RISES WILL BE GREATEST THROUGH THE MORNING AND
WITH GOOD MIXING TODAY...WILL SEE WINDS GUSTING INTO THE 20 TO 25
KT RANGE FOR ALL TERMINALS. SKIES WILL BE SUNNY AS DRY HIGH PRES
BUILDS IN. WINDS DIMINISH DRASTICALLY TOWARDS SUNSET AS THE
GRADIENT RELAXES AND CAA COMES TO A HALT. DO NOT EXPECT FOG OR BR
AS BNDRY LAYER WILL BE QUITE DRY WITH TD VALS IN THE LOW TO MID
20S OVERNIGHT.
LONG TERM /WEDNESDAY THROUGH SUNDAY/...
AS OF 300 AM WED...VFR THROUGH THE PERIOD. ISOLATED SHOWERS
POSSIBLE SUNDAY NIGHT WITH A STONGER UPR LEVEL TROF.
&&
.MARINE...
SHORT TERM /THROUGH TONIGHT/
AS OF 3 AM WED...CURRENT SFC OBS INDICATING MARGINAL GALE
CONDITIONS OCCURING OFF NC COAST. FRYING PAN BUOY GUSTING BETWEEN
35 AND 40 KT EARLY THIS MORNING...AND EARLIER SHIP OB 35 SE CAPE
LOOKOUT REPORTED SUSTAINED WINDS OF 35 KT. NEAR TERM GUIDANCE
INDICATES GREATEST ISALLOBARIC PRES RISES OCCURRING NEAR 12 Z THIS
MORNING. THIS IS IN LINE WITH HRRR WINDS GUSTS APPROACHING GALE
FORCE THROUGH ABOUT THIS TIME. 700 MB TROUGH AXIS WILL EXIT THE NC
COASTAL WATERS AFTER 12Z...AND WITH DEPARTING THOUGH DEEPENING LOW
ACROSS NEW ENGLAND...WINDS WILL BEGIN TO ABATE. CAA HOWEVER WILL
CONTINUE TO PRODUCE SCA WIND GUSTS THROUGH MUCH OF TODAY...AND
WILL HAVE TO REPLACE GALES WITH SCA AFTER THEIR SCHEDULED
EXPIRATION TIMES. SEAS WILL ALSO REMAIN ABOVE 6 FT FOR THE
REMAINDER OF TODAY...HIGHEST EARLY THIS MORNING.
LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 300 AM WED...BRIEF PERIOD OF LIGHTER WINDS AND SEAS THU
MORNING...THEN GRADIENT BETWEEN LOW PRESSURE MOVING ACROSS N OF AREA
AND HIGH PRESSURE TO S WILL PRODUCE INCREASING W TO SW WINDS THU
NIGHT INTO FRI NIGHT...WITH MARGINAL SCA CONDITIONS PSBL FOR OUTER
PORTIONS OF WATERS. WINDS BECOMING NRLY LATE SAT FOLLOWING DRY
FRONTAL PASSAGE...WITH SPEEDS DECREASING SAT NIGHT WITH HIGH PRES
BUILDING IN FROM W. WINDS WILL VEER QUICKLY BACK TO SW SUN AS HIGH
PRES MOVES OFFSHORE. BLEND OF WW3...LOCAL SWAN AND PREVIOUS FCST
USED FOR SEAS.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...WIND ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR NCZ103-104.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 PM EST THIS EVENING FOR AMZ130-
135.
GALE WARNING UNTIL 10 AM EST THIS MORNING FOR AMZ150-152-154.
GALE WARNING UNTIL 7 AM EST THIS MORNING FOR AMZ156-158.
&&
$$
SYNOPSIS...TL
NEAR TERM...TL
SHORT TERM...TL
LONG TERM...JBM
AVIATION...TL/JBM
MARINE...TL/JBM
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
708 AM EST WED DEC 28 2011
.SYNOPSIS...
BLUSTERY WEST WINDS WILL CREATE SOME LAKE EFFECT SNOW AND
FLURRIES TODAY...BUT THE SNOW SHOWERS WILL TAPER OFF THROUGH THE
DAY. WEAK HIGH PRESSURE TONIGHT WILL BE PUSHED TO THE SOUTH AS A
COUPLE OF ALBERTA CLIPPERS MOVE ACROSS THE GREAT LAKES THURSDAY
NIGHT AND FRIDAY...AND COULD PRODUCE A FEW INCHES OF SNOW IN THE
NORTH AND WEST. FAIR WEATHER SHOULD FOLLOW FOR SATURDAY.
&&
.NEAR TERM /UNTIL NOON TODAY/...
TIGHT P-GRADIENT AROUND THE DEPARTED STORM WILL CONTINUE TO CREATE
GUSTY WINDS OVER THE STATE. BUFKIT MOMENTUM TRANSFER VALUES FROM
NAM AND RUC SHOW GUSTS WILL PROBABLY TOP OUT IN THE M/U30KT
RANGE...BUT RUN THROUGH MUCH OF THE DAY. LAST VESTIGE OF THE UPPER
LOW APPEARS TO HAVE JUST PASSED KELZ AND KUNV. RADAR SHOWS SNOW IN
VERY LONG BUT ALSO VERY THIN/NARROW BANDS. VERY FEW IFR OBS TO BE
FOUND. THE GUSTY WINDS WILL BE CREATING A GREAT DEAL OF SHEAR IN
THE CLOUD LAYER. THIS WILL MEAN THAT THE BANDS WILL BE TRANSITORY.
SINCE THEY ARE SO NARROW...IT WILL BE DIFFICULT FOR EVEN LIGHT
ACCUMS TO OCCUR. THE INVERSION LOWERS A BIT THIS MORNING AS THE
HIGH OVER THE CENTRAL STATES SLIDES EASTWARD. WILL CONTINUE WITH
THE CURR ADVY IN THE NW 3 COS...CLOSE TO THE LAKE. BUT MOST
PLACES WILL STRUGGLE TO GET EVEN ANOTHER INCH...ESP SINCE THE
SNOW WILL BE BLOWING AROUND AND MAKE MEASURING DIFFICULT. CLOUDS
WILL START TO BREAK UP IN THE MORNING IN THE DOWNSLOPE AREAS...BUT
IT WILL BE TOUGH TO CLEAR UP SKIES OVER THE W.
&&
.SHORT TERM /NOON TODAY THROUGH 6 PM THURSDAY/...
LAKE EFFECT SNOW WANES IN WESTERN ZONES AS INVERSION HEIGHTS COME
DOWN LATER THIS MORNING AND EARLY THIS AFTN. ANY ACCUMS AFTER NOON
WILL BE NEGLIGIBLE. GUSTY WINDS WILL CONTINUE AS PRESSURE RISES
8-10 MB BEFORE SUNSET. TEMPS WILL BE FLAT OR EVEN DROP THROUGH THE
DAY AS THE 8H TEMPS DROP 7-8C THROUGH THE DAY.
THE SFC RIDGE SLIDES OVERHEAD THROUGH THE NIGHT...GRADUALLY
SLACKENING THE WINDS THIS EVENING AND EARLY TONIGHT. MINS WILL BE
IN THE TEENS AND L20S. THESE TEMPS ARE JUST ABOUT AS COLD AS WE
HAVE BEEN THIS WINTER...WITH ONLY THE 10TH-12TH OF THE MONTH AS
COLD OR COLDER. SUNSHINE EARLY IN THE DAY AND RETURN FLOW WILL
ALLOW TEMPS TO RISE BACK TO OR EVEN SLIGHTLY ABOVE NORMALS. AN
APPROACHING NRN STREAM WAVE WILL SPREAD HIGH/MID CLOUDS INTO THE
NRN TIER THROUGH THE DAY ON THURS...BUT ANY LIGHT SNOW SHOULD NOT
ARRIVE UNTIL LATE IN THE DAY IN THE NW.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
A QUICK MOVING CLIPPER SYSTEM WILL SHOOT THROUGH THE GREAT LAKES
AFFECTING MAINLY MY NORTHERN ZONES THURSDAY NIGHT. A SECONDARY
SHOT OF MOISTURE QUICKLY MOVES ALONG THE INTERSTATE 80 CORRIDOR
DURING THE DAY FRIDAY INTO SATURDAY MORNING. THESE FEATURES ARE
SIMILARLY HANDLED BY VARYING MODEL GUIDANCE WITH JUST A FEW
DIFFERENCES IN TIMING AND INTENSITY.
MODELS ALSO AGREE ON ANOTHER SHOT OF MOISTURE MOVING THROUGH LATE
SUNDAY INTO MONDAY AHEAD OF AN ARCTIC AIRMASS TO MOVE IN FOR THE
MIDDLE OF NEXT WEEK. AS WE MOVE INTO THAT TIMEFRAME...SIGNIFICANT
MODEL DIFFERENCES EXIST.
THE ECMWF BRINGS A SLOW MOVING STORM SYSTEM NORTHWEST FROM THE
ATLANTIC COAST WELL INTO PENNSYLVANIA BY THE MIDDLE OF NEXT WEEK.
HOWEVER...THE GFS HAS THE REGION IN COLD NORTHWEST FLOW WITH SOME
OF THE COLDEST AIR OF THE SEASON CLIPPING NORTHEAST PA WITH ONLY
RESULTANT LAKE EFFECT BRINGING SNOW TO THE AREA.
LACK OF SNOW BEGETS LACK OF SNOW. HUGE STORMS IN THE 5-7 DAY RANGE
FIZZLING BEGETS HUGE STORMS IN THE 5-7 DAY RANGE FIZZLING. IT IS
THE TREND OF THIS WINTER SO WILL HOLD OFF ON ANY BELLS...OR
WHISTLES...AT THIS POINT.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
WINDS NOW ARE NW. GUSTY WINDS WILL PREVAIL AS THE COLD AIR ADVECTS
THROUGH THE REGION. EXPECT LAKE ENHANCED SNOW SHOWERS CAUSING IFR
CONDITIONS AT BFD AND JST UNTIL LATE MORNING OR EARLY AFTERNOON.
MVFR CIGS AT UNV AND AOO AT TIMES THIS MORNING...AS THE UPPER LVL
TROUGH MOVES ACROSS. EXPECT VFR CONDITIONS FURTHER EAST.
GENERALLY VFR CONDS EXPECTED ON THU...ALTHOUGH SOME -SHSN ARE
POSSIBLE LATE ACROSS NW PA.
A SLIGHTLY BETTER CHC OF SNOW OR RAIN SHOWERS FRI...AS A CLIPPER
SYSTEM MOVES EASTWARD...JUST NORTH OF PA.
VFR CONDS RETURN FOR NEW YEARS WEEKEND...AS HIGH PRESSURE
BUILDS IN. PERHAPS A SHOWER LATE SUNDAY WITH THE NEXT
COLD FRONT.
OUTLOOK...
THU...GENERALLY VFR.
FRI...MVFR/IFR MAINLY WESTERN AREAS WITH RAIN/SNOW SHOWERS.
SAT-SUN...MAINLY VFR.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR PAZ004-005-
010.
&&
$$
SYNOPSIS...DANGELO
NEAR TERM...DANGELO
SHORT TERM...DANGELO
LONG TERM...TYBURSKI
AVIATION...CERU/MARTIN/EVANEGO
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
639 AM EST WED DEC 28 2011
.SYNOPSIS...
BLUSTERY WEST WINDS WILL CREATE SOME LAKE EFFECT SNOW AND
FLURRIES TODAY...BUT THE SNOW SHOWERS WILL TAPER OFF THROUGH THE
DAY. WEAK HIGH PRESSURE TONIGHT WILL BE PUSHED TO THE SOUTH AS A
COUPLE OF ALBERTA CLIPPERS MOVE ACROSS THE GREAT LAKES THURSDAY
NIGHT AND FRIDAY...AND COULD PRODUCE A FEW INCHES OF SNOW IN THE
NORTH AND WEST. FAIR WEATHER SHOULD FOLLOW FOR SATURDAY.
&&
.NEAR TERM /UNTIL NOON TODAY/...
TIGHT P-GRADIENT AROUND THE DEPARTED STORM WILL CONTINUE TO CREATE
GUSTY WINDS OVER THE STATE. BUFKIT MOMENTUM TRANSFER VALUES FROM
NAM AND RUC SHOW GUSTS WILL PROBABLY TOP OUT IN THE M/U30KT
RANGE...BUT RUN THROUGH MUCH OF THE DAY. LAST VESTIGE OF THE UPPER
LOW APPEARS TO HAVE JUST PASSED KELZ AND KUNV. RADAR SHOWS SNOW IN
VERY LONG BUT ALSO VERY THIN/NARROW BANDS. VERY FEW IFR OBS TO BE
FOUND. THE GUSTY WINDS WILL BE CREATING A GREAT DEAL OF SHEAR IN
THE CLOUD LAYER. THIS WILL MEAN THAT THE BANDS WILL BE TRANSITORY.
SINCE THEY ARE SO NARROW...IT WILL BE DIFFICULT FOR EVEN LIGHT
ACCUMS TO OCCUR. THE INVERSION LOWERS A BIT THIS MORNING AS THE
HIGH OVER THE CENTRAL STATES SLIDES EASTWARD. WILL CONTINUE WITH
THE CURR ADVY IN THE NW 3 COS...CLOSE TO THE LAKE. BUT MOST
PLACES WILL STRUGGLE TO GET EVEN ANOTHER INCH...ESP SINCE THE
SNOW WILL BE BLOWING AROUND AND MAKE MEASURING DIFFICULT. CLOUDS
WILL START TO BREAK UP IN THE MORNING IN THE DOWNSLOPE AREAS...BUT
IT WILL BE TOUGH TO CLEAR UP SKIES OVER THE W.
&&
.SHORT TERM /NOON TODAY THROUGH 6 PM THURSDAY/...
LAKE EFFECT SNOW WANES IN WESTERN ZONES AS INVERSION HEIGHTS COME
DOWN LATER THIS MORNING AND EARLY THIS AFTN. ANY ACCUMS AFTER NOON
WILL BE NEGLIGIBLE. GUSTY WINDS WILL CONTINUE AS PRESSURE RISES
8-10 MB BEFORE SUNSET. TEMPS WILL BE FLAT OR EVEN DROP THROUGH THE
DAY AS THE 8H TEMPS DROP 7-8C THROUGH THE DAY.
THE SFC RIDGE SLIDES OVERHEAD THROUGH THE NIGHT...GRADUALLY
SLACKENING THE WINDS THIS EVENING AND EARLY TONIGHT. MINS WILL BE
IN THE TEENS AND L20S. THESE TEMPS ARE JUST ABOUT AS COLD AS WE
HAVE BEEN THIS WINTER...WITH ONLY THE 10TH-12TH OF THE MONTH AS
COLD OR COLDER. SUNSHINE EARLY IN THE DAY AND RETURN FLOW WILL
ALLOW TEMPS TO RISE BACK TO OR EVEN SLIGHTLY ABOVE NORMALS. AN
APPROACHING NRN STREAM WAVE WILL SPREAD HIGH/MID CLOUDS INTO THE
NRN TIER THROUGH THE DAY ON THURS...BUT ANY LIGHT SNOW SHOULD NOT
ARRIVE UNTIL LATE IN THE DAY IN THE NW.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
A QUICK MOVING CLIPPER SYSTEM WILL SHOOT THROUGH THE GREAT LAKES
AFFECTING MAINLY MY NORTHERN ZONES THURSDAY NIGHT. A SECONDARY
SHOT OF MOISTURE QUICKLY MOVES ALONG THE INTERSTATE 80 CORRIDOR
DURING THE DAY FRIDAY INTO SATURDAY MORNING. THESE FEATURES ARE
SIMILARLY HANDLED BY VARYING MODEL GUIDANCE WITH JUST A FEW
DIFFERENCES IN TIMING AND INTENSITY.
MODELS ALSO AGREE ON ANOTHER SHOT OF MOISTURE MOVING THROUGH LATE
SUNDAY INTO MONDAY AHEAD OF AN ARCTIC AIRMASS TO MOVE IN FOR THE
MIDDLE OF NEXT WEEK. AS WE MOVE INTO THAT TIMEFRAME...SIGNIFICANT
MODEL DIFFERENCES EXIST.
THE ECMWF BRINGS A SLOW MOVING STORM SYSTEM NORTHWEST FROM THE
ATLANTIC COAST WELL INTO PENNSYLVANIA BY THE MIDDLE OF NEXT WEEK.
HOWEVER...THE GFS HAS THE REGION IN COLD NORTHWEST FLOW WITH SOME
OF THE COLDEST AIR OF THE SEASON CLIPPING NORTHEAST PA WITH ONLY
RESULTANT LAKE EFFECT BRINGING SNOW TO THE AREA.
LACK OF SNOW BEGETS LACK OF SNOW. HUGE STORMS IN THE 5-7 DAY RANGE
FIZZLING BEGETS HUGE STORMS IN THE 5-7 DAY RANGE FIZZLING. IT IS
THE TREND OF THIS WINTER SO WILL HOLD OFF ON ANY BELLS...OR
WHISTLES...AT THIS POINT.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
AS THE SYSTEM QUICKLY DEPARTS...WINDS WILL SHIFT FROM THE
WEST TO THE NORTHWEST. GUSTY WINDS WILL PREVAIL AS THE COLD AIR
ADVECTS THROUGH THE REGION. EXPECT LAKE ENHANCED SNOW SHOWERS
CAUSING IFR CONDITIONS AT BFD AND JST UNTIL LATE MORNING OR EARLY
AFTERNOON. MVFR CIGS AT UNV AND AOO AT TIMES THIS MORNING...AS THE
UPPER LVL TROUGH MOVES ACROSS. EXPECT VFR CONDITIONS FURTHER EAST.
GENERALLY VFR CONDS EXPECTED ON THU...ALTHOUGH SOME -SHSN ARE
POSSIBLE LATE ACROSS NW PA.
A SLIGHTLY BETTER CHC OF SNOW OR RAIN SHOWERS FRI...AS A CLIPPER
SYSTEM MOVES EASTWARD...JUST NORTH OF PA.
VFR CONDS RETURN FOR NEW YEARS WEEKEND.
OUTLOOK...
THU...GENERALLY VFR.
FRI...MVFR/IFR MAINLY WESTERN AREAS WITH RAIN/SNOW SHOWERS.
SAT-SUN...MAINLY VFR.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR PAZ004-005-
010.
&&
$$
SYNOPSIS...DANGELO
NEAR TERM...DANGELO
SHORT TERM...DANGELO
LONG TERM...TYBURSKI
AVIATION...CERU/MARTIN/EVANEGO
AREA FORECAST DISCUSSION...UPDATED
NWS MORRISTOWN TN
928 AM EST WED DEC 28 2011
.DISCUSSION...
REPORTS FROM THE MOUNTAINS INDICATE BETWEEN 1 AND 4 INCHES OF SNOW
HAS FALLEN OVERNIGHT AND THIS MORNING. LIGHT RADAR ECHOS HAVE
DIMINISHED FROM EARLIER THIS MORNING...AND THE 12Z OHX SOUNDING
SHOWS DRIER AIR WILL ADVECT IN THROUGH THE DAY. CLOUDS ACROSS THE
NORTHERN SECTIONS SHOULD BECOME SCATTERED BY MID AFTERNOON
ACCORDING TO THE RUC AND NAM. WILL UPDATE TO REMOVE ALL POPS...AND
WILL ALLOW THE WINTER WEATHER ADVISORY TO EXPIRE AT 10AM. ONLY
MINOR ADJUSTEMENTS WILL BE MADE TO HOURLY TEMPERATURES AND SKY
GRIDS FOR THE UPDATE.
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...WINTER WEATHER ADVISORY UNTIL 10 AM EST THIS MORNING FOR THE
FOLLOWING ZONES: BLOUNT SMOKY MOUNTAINS...COCKE SMOKY
MOUNTAINS...JOHNSON...SEVIER SMOKY MOUNTAINS...SOUTHEAST
CARTER...SOUTHEAST GREENE...UNICOI.
VA...WINTER WEATHER ADVISORY UNTIL 10 AM EST THIS MORNING FOR THE
FOLLOWING ZONES: WISE.
&&
$$
DGS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
857 PM CST THU DEC 29 2011
.SHORT TERM...
617 PM CST THU DEC 29 2011
CONTINUING TO MONITOR THE CURRENT FORECAST FOR TONIGHT AND HAVE A
BIT MORE CONCERN FOR ICING POTENTIAL. THE 29.18Z NAM/GFS ARE GOING
TO VERIFY VERY WELL AT 00Z WITH LOW CENTER OVER EAST-CENTRAL NEB
AND ECHO SOUTH TO ALMOST KANSAS CITY. THE BAD PART OF THAT
VERIFICATION IS THAT THE LOW TRACK ALONG I-80 FROM 29.18Z GFS/NAM
WOULD TAKE THE DEFORMATION SOUTH OF THE SNOW FORECAST WE HAVE AND
INTO A RAIN ENVIRONMENT. THIS WOULD MAKE MOST OF THE WEATHER A LOW
IMPACT SCENARIO AND LESS SNOW OBVIOUSLY.
ON THE OTHER HAND...
THE LATEST RUC RUNS ARE CONTINUING A BIT FURTHER NORTH TRACK TO
THE LOW AND IT BREAKS OUT AN EAST-WEST DEFORMATION ALONG IA-MN
BORDER WHICH IS MORE ALONG CURRENT FORECAST IDEA. HOWEVER...THERE
IS A SIGNIFICANT WARM LAYER THAT SURGES NORTH INTO THE AREA AHEAD
OF THE PRECIPITATION...MAKING A PERIOD OF FREEZING RAIN A SURE BET
/PER RUC/ FOR AREAS SEEING SURFACE TEMPERATURES AT OR BELOW 32F.
BASED ON CURRENT TEMPERATURES IT MIGHT BE A BAND OF FREEZING RAIN
ALONG I-90 ROUGHLY...LIMITED BY >33F TO THE SOUTHWEST /JUST RAIN/.
WOULD THINK THAT IF PRECIPITATION IS HEAVY ENOUGH...COLUMN COOLING
WOULD HELP TO CHANGE THE TYPE OVER TO SNOW AFTER HOURS TO LIMIT
THE ICING. A SNOW/SLEET BAND WOULD BE LIKELY TO THE NORTH OF THAT
FZRA...BUT LIGHTER PRECIPITATION THAN CURRENT FORECAST.
PLAN TO CONTINUE TO MONITOR INCOMING DATA OVER NEXT TWO HOURS AND
TRY TO MAKE ADJUSTMENTS BY 9 PM. BASED ON RUC/HRRR GUIDANCE AND
EVEN A BIT WIDER NAM/GFS DEFORMATION BAND...AN ADVISORY FOR ICING
CANNOT BE RULED OUT TONIGHT.
.LONG TERM...SUNDAY NIGHT THROUGH THURSDAY
334 PM CST THU DEC 29 2011
HIGHLY AMPLIFIED FLOW TO START THE LATER PERIODS WITH LARGE WEEKEND
TROUGH OFF TO THE EAST. FAIRLY GOOD AGREEMENT IN MEDIUM RANGE
GUIDANCE LEADS TO HIGHER CONFIDENCE IN WHAT LOOKS LIKE A FAIRLY
QUIET WEEK TO START NEW YEAR.
WINDS WILL REMAIN UP FROM PRESSURE GRADIENT SUNDAY NIGHT BUT RIDGE
AXIS SHIFTS IN MONDAY AND TUESDAY DROPPING TEMPERATURES BACK TO
SEASONAL NORMALS OR PERHAPS A BIT BELOW FOR A CHANGE. DEPENDING ON
WHERE SNOW FALLS FOR NEW YEARS STORM...COULD BE SOME SNOW PACK WHICH
WOULD HIGHLY INFLUENCE LOWS...ESPECIALLY TUESDAY MORNING. HAVE
LOWERED THEM A BIT AS A TREND.
29.12Z GFS FASTER WITH A SHORT WAVE PASSING THROUGH UPPER RIDGE
HEADING INTO TUESDAY NIGHT COMPARED TO 29.12Z ECMWF BUT EITHER WAY
THIS FEATURE COULD GENERATE ENOUGH LIFT ON NOSE OF WARMER AIR FOR
SNOW THREAT EITHER TUESDAY NIGHT OR WEDNESDAY IN NORTH CENTRAL
REGIONS. NOT ENOUGH CONFIDENCE OR COLLABORATION TO INCLUDE AT THIS
POINT BUT SMALL CHANCES CAN NOT BE RULED OUT. BEYOND THAT UPPER
RIDGE BUILDS IN EVEN STRONGER FOR NATIONS MID-SECTION AND DEPENDING
ON ANY LINGERING SNOW COVER...COULD MEAN DRAMATIC WARM UP AGAIN.
&&
.AVIATION...TONIGHT AND FRIDAY
617 PM CST THU DEC 29 2011
FORECAST OVERNIGHT IS A CHALLENGE AS MULTIPLE PRECIPITATION TYPES
COULD AFFECT THE TAF SITES. ALSO...CURRENT OBSERVATIONS SUGGEST
THE WEATHER CURRENTLY IN THE TAFS COULD SHIFT SOUTH
ALTOGETHER...AND INTO IOWA. FOR THIS ISSUANCE...HAVE REMAINED WITH
THE IDEA THAT SNOW WOULD FALL OVERNIGHT AT BOTH
KLSE/KRST...HOWEVER WITH A WARM AIR SURGE COMING NORTH...AND
SURFACE TEMPERATURES RIGHT NEAR FREEZING...AM INCREASINGLY
CONCERNED ABOUT FREEZING RAIN AND ICE ACCUMULATION FOR THE
AIRPORTS. HAVE ADDED FZRA TO THE TAFS FOR THE OVERNIGHT.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...PRELIM HEADLINES.
856 PM CST THU DEC 29 2011
WI...WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO NOON CST FRIDAY
FOR WIZ054-061.
MN...WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO NOON CST FRIDAY
FOR MNZ086-087-094-095.
IA...WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO NOON CST FRIDAY
FOR IAZ008>011-018-019-029-030.
&&
$$
SHORT TERM...BAUMGARDT
LONG TERM....SHEA
AVIATION...BAUMGARDT
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
617 PM CST THU DEC 29 2011
.SHORT TERM...
617 PM CST THU DEC 29 2011
CONTINUING TO MONITOR THE CURRENT FORECAST FOR TONIGHT AND HAVE A
BIT MORE CONCERN FOR ICING POTENTIAL. THE 29.18Z NAM/GFS ARE GOING
TO VERIFY VERY WELL AT 00Z WITH LOW CENTER OVER EAST-CENTRAL NEB
AND ECHO SOUTH TO ALMOST KANSAS CITY. THE BAD PART OF THAT
VERIFICATION IS THAT THE LOW TRACK ALONG I-80 FROM 29.18Z GFS/NAM
WOULD TAKE THE DEFORMATION SOUTH OF THE SNOW FORECAST WE HAVE AND
INTO A RAIN ENVIRONMENT. THIS WOULD MAKE MOST OF THE WEATHER A LOW
IMPACT SCENARIO AND LESS SNOW OBVIOUSLY.
ON THE OTHER HAND...
THE LATEST RUC RUNS ARE CONTINUING A BIT FURTHER NORTH TRACK TO
THE LOW AND IT BREAKS OUT AN EAST-WEST DEFORMATION ALONG IA-MN
BORDER WHICH IS MORE ALONG CURRENT FORECAST IDEA. HOWEVER...THERE
IS A SIGNIFICANT WARM LAYER THAT SURGES NORTH INTO THE AREA AHEAD
OF THE PRECIPITATION...MAKING A PERIOD OF FREEZING RAIN A SURE BET
/PER RUC/ FOR AREAS SEEING SURFACE TEMPERATURES AT OR BELOW 32F.
BASED ON CURRENT TEMPERATURES IT MIGHT BE A BAND OF FREEZING RAIN
ALONG I-90 ROUGHLY...LIMITED BY >33F TO THE SOUTHWEST /JUST RAIN/.
WOULD THINK THAT IF PRECIPITATION IS HEAVY ENOUGH...COLUMN COOLING
WOULD HELP TO CHANGE THE TYPE OVER TO SNOW AFTER HOURS TO LIMIT
THE ICING. A SNOW/SLEET BAND WOULD BE LIKELY TO THE NORTH OF THAT
FZRA...BUT LIGHTER PRECIPITATION THAN CURRENT FORECAST.
PLAN TO CONTINUE TO MONITOR INCOMING DATA OVER NEXT TWO HOURS AND
TRY TO MAKE ADJUSTMENTS BY 9 PM. BASED ON RUC/HRRR GUIDANCE AND
EVEN A BIT WIDER NAM/GFS DEFORMATION BAND...AN ADVISORY FOR ICING
CANNOT BE RULED OUT TONIGHT.
.LONG TERM...SUNDAY NIGHT THROUGH THURSDAY
334 PM CST THU DEC 29 2011
HIGHLY AMPLIFIED FLOW TO START THE LATER PERIODS WITH LARGE WEEKEND
TROUGH OFF TO THE EAST. FAIRLY GOOD AGREEMENT IN MEDIUM RANGE
GUIDANCE LEADS TO HIGHER CONFIDENCE IN WHAT LOOKS LIKE A FAIRLY
QUIET WEEK TO START NEW YEAR.
WINDS WILL REMAIN UP FROM PRESSURE GRADIENT SUNDAY NIGHT BUT RIDGE
AXIS SHIFTS IN MONDAY AND TUESDAY DROPPING TEMPERATURES BACK TO
SEASONAL NORMALS OR PERHAPS A BIT BELOW FOR A CHANGE. DEPENDING ON
WHERE SNOW FALLS FOR NEW YEARS STORM...COULD BE SOME SNOW PACK WHICH
WOULD HIGHLY INFLUENCE LOWS...ESPECIALLY TUESDAY MORNING. HAVE
LOWERED THEM A BIT AS A TREND.
29.12Z GFS FASTER WITH A SHORT WAVE PASSING THROUGH UPPER RIDGE
HEADING INTO TUESDAY NIGHT COMPARED TO 29.12Z ECMWF BUT EITHER WAY
THIS FEATURE COULD GENERATE ENOUGH LIFT ON NOSE OF WARMER AIR FOR
SNOW THREAT EITHER TUESDAY NIGHT OR WEDNESDAY IN NORTH CENTRAL
REGIONS. NOT ENOUGH CONFIDENCE OR COLLABORATION TO INCLUDE AT THIS
POINT BUT SMALL CHANCES CAN NOT BE RULED OUT. BEYOND THAT UPPER
RIDGE BUILDS IN EVEN STRONGER FOR NATIONS MID-SECTION AND DEPENDING
ON ANY LINGERING SNOW COVER...COULD MEAN DRAMATIC WARM UP AGAIN.
&&
.AVIATION...TONIGHT AND FRIDAY
617 PM CST THU DEC 29 2011
FORECAST OVERNIGHT IS A CHALLENGE AS MULTIPLE PRECIPITATION TYPES
COULD AFFECT THE TAF SITES. ALSO...CURRENT OBSERVATIONS SUGGEST
THE WEATHER CURRENTLY IN THE TAFS COULD SHIFT SOUTH
ALTOGETHER...AND INTO IOWA. FOR THIS ISSUANCE...HAVE REMAINED WITH
THE IDEA THAT SNOW WOULD FALL OVERNIGHT AT BOTH
KLSE/KRST...HOWEVER WITH A WARM AIR SURGE COMING NORTH...AND
SURFACE TEMPERATURES RIGHT NEAR FREEZING...AM INCREASINGLY
CONCERNED ABOUT FREEZING RAIN AND ICE ACCUMULATION FOR THE
AIRPORTS. HAVE ADDED FZRA TO THE TAFS FOR THE OVERNIGHT.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
334 PM CST THU DEC 29 2011
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BAUMGARDT
LONG TERM....SHEA
AVIATION...BAUMGARDT
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
316 AM CST FRI DEC 30 2011
.SYNOPSIS...
06Z SFC ANALYSIS HAS A SFC LOW BETWEEN KDNS AND KADU WITH A WARM
FRONT RUNNING EAST TO KC75 AND KPNT. A INVERTED TROF RAN INTO
ANOTHER WARM FRONT IN NORTHEAST SOUTH DAKOTA AND THEN ANOTHER SFC
LOW NORTHEAST OF KBIS. DEW POINTS WERE GENERALLY IN THE 30S WITH
40S FROM THE LOWER MISSISSIPPI VALLEY INTO THE LOWER OHIO VALLEY.
RADAR TRENDS SHOW A BAND OF WAA PRECIPITATION FROM NORTHEAST
IOWA INTO NORTHERN ILLINOIS WITH ANOTHER DEVELOPING FROM CENTRAL
IOWA INTO CENTRAL ILLINOIS.
&&
.SHORT TERM...TODAY AND TONIGHT
A COMBINATION OF NOWCASTING TOOLS AND RUC TRENDS WERE USED TO
HANDLE FOR TODAY.
THE RUC 300K THETA SFC IN FORCING AND CONDENSATION PRESSURE
DEFICITS DEPICTS QUITE WELL WHAT IS CURRENTLY GOING ON. THE
INITIAL BAND OF WAA PRECIPITATION WILL ROTATE OUT OF THE CWFA BY
12Z. A NEW BAND OF WAA PRECIPITATION DEVELOPING OVER THE CWFA WILL
MOVE ACROSS THE NORTHERN THIRD OF THE CWFA BETWEEN 6 AND 9 AM. WBZ
TEMPERATURES AT THE SFC AND 925MB RISE THE REMAINDER OF THE NIGHT
AND DURING THE MORNING SO THE PRECIPITATION WILL BE ALL RAIN
EXCEPT IN THE HWY 20 CORRIDOR WHERE A MIX IS EXPECTED TO PERSIST
DURING THE MORNING.
LIFT TOOL INDICATES CONVECTIVE PRECIPITATION DEVELOPING ALONG AND
SOUTH OF I-80 THIS MORNING AND RADAR TRENDS DO SUGGEST THIS IS
OCCURRING.
BY MID DAY THE SFC LOW SHOULD BE OVER THE EASTERN CWFA JUST SOUTH
OF I-80 WITH A DEFORMATION ZONE SETTING UP ACROSS THE NORTHERN
THIRD OF THE CWFA. WBZ TEMPERATURES AT THE SFC AND 925MB FROM MID
DAY THROUGH MID AFTERNOON ARE ABOVE 34 DEGREES SO PRECIPITATION
WILL BE ALL RAIN ACROSS THE CWFA.
WRF TRENDS...ASSUMING THEY ARE CORRECT...INDICATE WBZ TEMPERATURES
DROPPING BACK TO 32 DEGREES OR LOWER FROM 3 TO 6 PM INDICATING A
MIX REDEVELOPING NORTH OF HWY 30 WITH A POSSIBLE CHANGE OVER TO
ALL SNOW IN THE HWY 20 CORRIDOR. SNOW ACCUMULATIONS TODAY ARE
EXPECTED TO BE AN INCH OR LESS.
TONIGHT...WRF TRENDS INDICATE PRECIPITATION LINGERING INTO THE
EVENING HOURS ACROSS THE EASTERN CWFA. WBZ TEMPERATURES INDICATE A
MIX WITH POSSIBLY SOME LIGHT SNOW IN THE HWY 20 CORRIDOR EAST OF
DUBUQUE. HOWEVER...CONDENSATION PRESSURE DEFICITS RISE RAPIDLY
DURING THE EVENING WITH THE FORCING SHUTTING DOWN. THUS ANY SNOW
ACCUMULATION SHOULD BE A DUSTING AT BEST.
..08..
.LONG TERM...SATURDAY THROUGH THURSDAY...
THE UPS AND DOWNS MORE ASSOCIATED WITH FALL WEATHER WILL DOMINATE
THE EXTENDED FORECAST. SATURDAY SHOULD BE VERY MILD ONCE AGAIN...AS
A VERY STRONG SHORT WAVE DIGS INTO THE PLAINS AND RAPIDLY DROPS THE
SURFACE PRESSURE OVER THE MIDWEST. THIS WILL DRAW SOUTHERLY WINDS UP
OVER THE CWA...WHICH WILL BE MOST CERTAINLY GUSTY AT TIMES. THE DAY
SHOULD SHOULD SEE PASSING MID CLOUDS...BUT WITH THE GUSTY WINDS AND
SEASONALLY DEEP MIXING...IT SEEMS PRUDENT TO GO ABOVE GUIDANCE FOR
HIGHS. THUS...WILL STAY CLOSE TO THE PREVIOUS FORECAST AND GO MID
40S NORTHEAST TO MID 50S SOUTHWEST FOR HIGHS. LOW PRESSURE SHOULD
RAPIDLY SHIFT NORTHEAST INTO THE GREAT LAKES...WITH STRONG HIGH
PRESSURE RAPIDLY MOVING INTO THE GREAT PLAINS. WINDS JUST ALOFT WILL
INCREASE TO 40 TO 50 KTS FROM THE NORTHWEST...BRINGING IN STRONG CAA
SATURDAY NIGHT AND SUNDAY. WINDS SHOULD BE PUSHING ADVISORY DURING
THIS PERIOD...WITH SUSTAINED WINDS EASILY SEEING AROUND 25
MPH...POSSIBLY 30...AND GUSTS OF 40 TO 45 LIKELY. WILL HIGHLIGHT
THIS IN THE HWO. AFTER A SLIGHT TO LOW CHANCE FOR RAIN...POSSIBLY
MIXING WITH SNOW NORTHWEST SATURDAY NIGHT...ALL OF WHICH SEEMS LIGHT
AND NON HAZARDOUS...WE WILL ONCE AGAIN GO INTO A DRY PATTERN THE
REMAINING EXTENDED FORECAST. THUS...THE WIND AND COLD AIR IS THE
MAIN STORY FOLLOWING TODAYS PCPN EVENT. WITH TEMPERATURES ALOFT
CRASHING DOWN INTO THE -12 TO -17 RANGE AT 850MB...WE WILL BE SEEING
THE COLDEST WEATHER IN MANY WEEKS. LOOK FOR SLOWLY FALLING
TEMPERATURES IN THE LOWER TO MID 30S SUNDAY...THEN LOWS IN THE TEENS
SUNDAY NIGHT. TEMPS WILL ONLY LIKELY RISE TO THE LOWER 20S NORTH TO
UPPER 20S SOUTHWEST MONDAY WHICH WILL BE THE COLDEST DAY IN THIS
STRETCH. WHILE SHARPLY COLDER THAN LATELY...THESE TEMPERATURES ARE
CLOSER TO NORMAL THAN THE RECENT MILD TEMPERATURES. A CHILLY NIGHT
MONDAY NIGHT WITH LOWS IN THE 11 TO 18 RANGE FROM NORTH TO SOUTH IS
EXPECTED TO GIVE WAY TO WIDESPREAD MILDER AIR AGAIN NEXT WEEK.
GLOBAL MODELS AGREE ON SHIFTING THE COLD HIGH PRESSURE EAST
TUESDAY...ALLOWING SEVERAL DAYS OF SOUTHWEST FLOW FOR THE MID TO
LATE WEEK. THUS...LOOK FOR ANOTHER STAIR STEP UPWARD ON
TEMPERATURES...LEADING TO ANOTHER MILD WEDNESDAY AND THURSDAY. WE
HAVE GONE WITH MID 30S TO AROUND 40 WEDNESDAY AND AND LOWER TO MID
40S THURSDAY. IT DOES APPEAR THAT WE MAY NEED TO INCREASE THESE
TEMPERATURES EVEN FURTHER...AS WE WILL LIKELY HAVE LITTLE MIDWESTERN
SNOW COVER AROUND TO HOLD SHALLOW COLD AIR IN PLACE.
..ERVIN..
&&
.AVIATION... /ISSUED 1149 PM CST THU DEC 29 2011/
THE LOWER CIGS/VSBYS NEAR THE SURFACE LOW IN EASTERN NE HAVE BEEN
SLOW TO MATERIALIZE WITH MOST OF THE LOW CIGS/VSBYS WELL NORTH OF
THE LOW IN THE COLDER AIR. AS A RESULT THE 06Z TAFS HAVE BACKED
OFF ON THE TIMING OF THE IFR OR LOW MVFR CONDITIONS AND KEPT THE
LOWER CONDITIONS CLOSE TO THE SURFACE LOW AS IT MOVES THROUGH THE
AREA FRIDAY MORNING. THE LOWEST CONDITIONS SHOULD BE SEEN AT KMLI/KCID/KDBQ.
BETWEEN 10Z AND 16Z. MOST TAFS SITES WILL SEE PERIODS OF RAIN
THROUGH FRIDAY MORNING WITH THE RAIN MIXING WITH OR CHANGING TO
LIGHT SNOW AND CONTINUING INTO FRIDAY AFTERNOON. IF ANY
ACCUMULATIONS OCCUR THEY SHOULD BE LIMITED TO THE FAR NORTH.
INCREASING NORTHWEST WINDS FRIDAY MORNING WILL HELP LIFT CIGS INTO
THE MVFR RANGE WITH MVFR CONDITIONS REMAIN OVER THE AREA THROUGH
FRIDAY EVENING. ..DLF..
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
430 AM EST FRI DEC 30 2011
.SYNOPSIS...
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW WNW FLOW ALF OVER
THE GRT LKS BTWN LO AMPLITUDE RDGING OVER THE W AND A TROF N JUST
OFF THE E COAST. SHRTWV RESPONSIBLE FOR SN ON THU IS PUSHING EWD
TOWARD SE ONTARIO...BUT WEAK SFC-H85 TROF REMAINS OVER ERN UPR MI.
BUT WITH DNVA/DEEP LYR QVECTOR DVGC/SUBSIDENCE/DRYING ALF IN THE
WAKE OF THE SHRTWV...THE PCPN OVER THE CWA HAS PRETTY MUCH ENDED.
THE MQT 88D DOES SHOW HIER RADAR RETURNS OVER ECNTRL LK SUP NEAR
WEAK SFC LO CENTER. 00Z INL RAOB SHOWS SHARP INVRN BASE NEAR H875
WITH TEMP JUST BLO THE INVRN DOWN TO -14C...LO ENUF TO SUPPORT LES.
ALTHOUGH THE 00Z INL RAOB INDICATES MODEST DRYING IN THE SUB INVRN
LYR...SKIES ARE GENERALLY CLDY AT MOST LOCATIONS FM THE MN ARROWHEAD
SEWD THRU UPR MI...BUT SOME BREAKS IN THE CLDS ARE EVIDENT. FARTHER
TO THE W/SW IN MN/WI...SKIES ARE MOCLR CLOSER TO WEAK SFC RDG AXIS
ASSOCIATED WITH INCOMING SHRTWV RDG MOVING E THRU MN. ANOTHER PAIR
OF SHRTWVS ARE NOTED IN THE NRN/CNTRL PLAINS...BUT THESE APPEAR TO
BE DIGGING TO THE SE. MUCH FARTHER TO THE W...A STRONG SHRTWV IS
APRCHG THE PAC NW. UPSTREAM HI TEMPS YDAY SUG MAX TEMPS WL GENERALLY
BE ARND 30.
&&
.DISCUSSION...
MAIN FCST CONCERNS THIS PACKAGE SHIFT TO POTENTIAL SN EVENT ON NEW
YEARS DAY/MON RELATED TO SHRTWV NOW APRCHG THE PAC NW.
TDAY...LOOKS LIKE A RELATIVELY QUIET DAY ON TAP WITH WEAK HGT
RISES/DRYING ALF IN THE WAKE OF DEPARTING SHRTWV. SHRTWV COMPLEX IN
THE PLAINS IS FCST TO CONSOLIDATE IN THE LOWER GRT LKS...WITH
ACCOMPANYING DEEP LYR QVECTOR CNVGC/PCPN PASSING S OF UPR MI. FCST
SDNGS SHOW INVRN BASE SINKING TO H9-925 OVER THE CWA IN THE AFTN...
WITH INVRN BASE TEMPS NO LOWER THAN ABOUT -8C. CONSIDERING
THE WEAK SFC WINDS FCST THAT WOULD NOT SUPPORT ORGANIZATION OF LES
BANDS...THE MARGINAL NATURE OF THE CHILL/DGZ ABV THE SUB INVRN
LYR...AND SOME LLVL DRYING...SUSPECT THERE WL BE LTL IN THE WAKE OF
LES. BUT SINCE THE 00Z INL RAOB DID SHOW -14C AIR AT THE H875 INVRN
BASE AND THE GFS/NAM MODEL ANALYSIS WAS ABOUT 3C TOO WARM AT THAT
SITE...WL MAINTAIN GOING POPS NEAR LK SUP...ESPECIALLY E OFMQT WHERE
WEAK SFC TROF IS FCST TO PERSIST THRU THE DAY. ALSO ADDED A MENTION
OF FZDZ IN THIS AREA WHERE THE LLVL MSTR REMAINS A BIT MORE
RESILIENT AND THE LLVL TEMPS ARE NOT LIKELY TO BE AS LO AS OBSVD AT
INL.
TNGT...SHRTWV RDGING WL BE DOMINATING WITH WEAK SFC HI PRES RDG
AXIS BLDG OVHD. MAINTAINED LO CHC POPS IN THE EVNG OVER THE E WHERE
THE SFC LO PRES TROF WL LINGER WHILE SLOWLY WEAKENING WITH TIME.
EXPECT THE LOWEST MIN TEMPS OVER THE INTERIOR SCNTRL WHERE SKIES WL
TREND MOCLR UNDER LIGHT SFC ACYC FLOW.
SAT...AS SHRTWV COMPLEX NOW MOVING TOWARD THE PAC NW SPLITS AND
DEEPENS TROFS IN SCNTRL CAN AND THE CENTRAL PLAINS...INCRSG SW FLOW
WL DVLP OVER THE UPR LKS AND RETURN DEEPER MSTR TO THE UPR LKS. WITH
INITIAL LLVL DRY AIR...RESTRICTED POPS MAINLY ON SAT AFT TO THE NW
HALF OF THE CWA WHERE GUIDANCE SHOWS DEEPER MOISTENING ON CYC SIDE
OF UPR JET AXIS ROTATING NEWD TOWARD THE UPR LKS BY 00Z SUN. SFC
TEMPS ARE PROGGED TO RISE AOA 32 IN THE AFTN AS H85 TEMPS RISE TO
ARND 0C...BUT NAM/SREF FCST WBLB ZERO HGT BLO 500 AGL WITH LINGERING
LLVL DRY AIR SUG VERY LTL CHC RA MAY BE MIXED WITH THE PCPN AT THE
ONSET.
SAT NGT INTO MON...MODELS HAVE BEGUN TO CONVERGE ON A SCENARIO
SHOWING A DEEPENING UPR TROF/SFC LO AS SEPARATE SHRTWVS IN SCNTRL
CAN AND THE CENTRAL PLAINS PHASE. THE GFS IS MOST AGGRESSIVE AT
DEEPENING A CLOSED LO...SHOWING A 984MB SFC LO OVER NRN LK MI BY 12Z
SUN. PER NCEP DISCUSSION...USED A BLEND OF THE INTERMEDIATE STRENGTH
00Z NAM/00Z CNDN/21Z SREF/12Z ECMWF FOR FCST PREPARATION. THESE
MODELS SHOW SFC LO TRACKING ACRS LK SUP/SRN ONTARIO SAT NGT AND
DRAWING ENUF LLVL MSTR OVER UPR MI TO SUPPORT LIKELY POPS UNDER UPR
DVGC ON CYC SIDE OF JET AXIS WHERE 12HR H5 FALLS APRCH 200M. WITH
THE ARRIVAL OF MORE LLVL MSTR OVER THE E...FCST THKNS/WBLB ZERO HGT
SUPPORT AT LEAST A MIX WITH RA IN THAT AREA. ONCE THE LO SHIFTS TO
THE NE LATE SAT NGT/SUN...STRONG NW WINDS WITH H85 WINDS AOA 50KT
ADVECT MUCH COLDER AIR INTO THE UPR LKS...SETTING UP A LK ENHANCED
SN EVENT WITH FCST SDNGS SHOWING DEEP MSTR UNDER LO HGTS AND OMEGA
WITHIN THE LOWERING DGZ AND SHARP CYC FLOW. GUSTY NW WINDS WL ALSO
RESULT IN CONSIDERABLE BLSN. THIS LK ENHANCED SN WL THEN PERSIST
INTO MON BEFORE THE DEEPER MSTR SLOWLY EXITS AND PCPN TENDS TOWARD
PURE LES BY MON NGT. CONSIDERED DOING A WATCH FOR THE NW WIND SN
BELTS...ESPECIALLY OVER THE W WHERE MOST RECENT NCEP GUIDANCE SHOWS
UP TO A FOOT OF SN THRU 12Z MON. BUT SINCE THE BULK OF THE MOST
SGNFT WX WL OCCUR IN THE 5TH TO 7TH PERIODS...OPTED TO ISSUE AN SPS
TO COVER THIS POTENTIAL WINTER STORM.
EXTENDED...LATEST GUIDANCE IN GOOD AGREEMENT SHOWING DEEP UPR TROF
GIVING WAY TO A MORE ZONAL FLOW AFT MID WEEK WITH A WARMING TREND.
DID LOWER FCST MIN TEMPS A FEW DEGREES FM THE ALLBLEND FCST OVER THE
INTERIOR W HALF ON MON NGT GIVEN ARRIVAL OF SFC RDG AXIS/LGT
WINDS/PWAT AS LO AS 0.1 INCH.
&&
.AVIATION /FOR THE 06Z TAF ISSUANCE/...
LIGHT LOW-LEVEL WIND REGIME THRU THIS FCST PERIOD SUGGESTS
CONDITIONS PROBABLY WON`T CHANGE MUCH AT KIWD/KCMX/KSAW. SO...GIVEN
THE LOW-LEVEL MOISTURE OVER THE AREA AND GENERAL MVFR CIGS...MVFR
CIGS WILL LIKELY PREVAIL THRU THE FCST PERIOD. HOWEVER...THERE MAY
BE SOME PERIODS WHERE CLOUDS SCATTER OUT OR CIGS RISE TO VFR AS
INDICATED BY CURRENT REGIONAL SFC OBS AND SATELLITE IMAGERY.
&&
.MARINE /FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE/...
WINDS WILL DIMINISH TODAY AS LOW PRESSURE TROUGH LINGERS OVER LAKE
SUPERIOR. A WEAK RIDGE WILL THEN SLIDE ACROSS LAKE SUPERIOR INTO
SATURDAY BEFORE A STRONG LOW DEVELOPS OVER THE PLAINS AND MOVES
NORTH OF LAKE SUPERIOR FOR NEW YEARS DAY. HIGH END GALES ARE LOOKING
LIKELY FROM THIS SYSTEM...BEGINNING ON NEW YEARS DAY AND CONTINUING
THROUGH MONDAY AS COLDER AIR PLOWS INTO THE GREAT LAKES. HEAVY
FREEZING SPRAY ALSO MAY OCCUR SUNDAY NIGHT INTO MONDAY. GALE AND
HEAVY FREEZING SPRAY WATCHES WILL LIKELY NEED TO BE ISSUED IN THE
NEXT COUPLE DAYS. WINDS DIMINISH SIGNIFICANTLY BY NEXT TUESDAY WITH
ARRIVAL OF HIGH PRESSURE RIDGE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...KC
DISCUSSION...KC
AVIATION...ROLFSON
MARINE...TITUS
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1148 PM CST THU DEC 29 2011
.AVIATION...
NO FLIGHT RESTRICTIONS ARE EXPECTED FROM CEILING AND VISIBILITY
IN CENTRAL OR WESTERN NEBRASKA THROUGH FRIDAY EVENING AND OVERNIGHT.
AFTER DECREASING TONIGHT BY 08Z...WIND WILL BE 260-280 AT MOST
LOCATIONS AT 10-12KT THROUGH THE DAY FRIDAY.
&&
PREV DISCUSSION... /ISSUED 321 PM CST THU DEC 29 2011/
DISCUSSION...
SHORT TERM...
WIND ADVISORY CONDITIONS ARE SPREADING THROUGH ALL OF THE WRN NEB
PANHANDLE THIS AFTERNOON. THERE IS THE POTENTIAL FOR STRONG WINDS
TO SPREAD THROUGH ALL OF THE PANHANDLE UNTIL 23Z. THEREAFTER THE
LOSS OF DAYTIME HEATING SHOULD CAUSE A DROP IN GUSTS. 30 MPH
SUSTAINED CONDITIONS MIGHT CONTINUE THIS EVENING AS LOW PRESSURE
TRACKS THROUGH THE MISSOURI BASIN. THE RUC SHOWS A PRONOUNCED TROP
FOLD ON THE PV15 SURFACE WHICH SHOULD MOVE THRU THE FCST AREA THIS
EVENING. THUS THE WIND ADZY WILL CONTINUE ACROSS GARDEN AND DEUEL
COUNTIES WITH A POSSIBLE NORTH AND EAST EXPANSION AS CONDITIONS
WARRANT. SCATTERED SHOWERS ISOLATED THUNDERSTORMS ARE EXPECTED TO CONTINUE
TRACKING THRU NRN NEB THIS EVENING.
THE STRONG WEST WINDS ARE BEING USHERED IN AHEAD OF A PACIFIC COLD
FRONT WORKING THRU NERN WY. THE FRONT SHOULD COOL TEMPS OFF
SOMEWHAT FOR FRIDAY WITH HIGHS ABOUT 10F COOLER THAN TODAY.
ANOTHER STRONG COLD FRONT IS EXPECTED TO MOVE THROUGH SATURDAY
MORNING...EARLY AFTERNOON. THIS FRONT IN COMBINATION WITH
DEEPENING LOW PRESSURE ACROSS THE UPPER MIDWEST AND VERY STRONG
PACIFIC HIGH PRESSURE SHOULD PRODUCE WIND ADVISORY CONDITIONS
ACROSS MOST AND POSSIBLY ALL OF THE FCST AREA. A BLEND OF MODEL
DATA AND GUIDANCE WAS USED FOR THE FCST WHICH PRODUCED HIGH END
WIND ADVISORY CONDITIONS ACROSS SWRN NEB.
AMPLE MOISTURE WILL BE PRESENT ALONG AND BEHIND THE FRONT SATURDAY
FOR SCATTERED RAIN AND SNOW SHOWERS...MAINLY ACROSS THE NORTH.
ANOTHER STRONG TROP FOLD WILL SWEEP THE FCST AREA IN CONCERT WITH
THE FRONTAL PASSAGE. THE GFS WAS OVERPOWERING WITH THE WIND
STRENGTH AND COLD AIR PRODUCING ALL SNOW WHILE THE NAM SHOWED A
MIX WITH WEAKER WINDS. THE WARMER NAM WAS PREFERRED.
PACIFIC HIGH PRESSURE WILL BUILD ACROSS THE FCST AREA SUNDAY
PRODUCING HIGHS IN THE UPPER 30S TO AROUND 40 WITH NEARLY CLEAR SKIES.
LONG TERM...
A RIDGE OF HIGH PRESSURE ALOFT WILL BE AMPLIFYING MONDAY ACROSS THE
ROCKIES...WHILE A TROUGH OF LOW PRESSURE CONTINUES IT/S EASTWARD
PROGRESSION INTO THE NORTHEAST STATES. OUR AREA WILL BE IN BETWEEN
THESE TWO FEATURES...WITH A BROAD NORTHWEST FLOW ALOFT. 850 MB
TEMPERATURES WILL BEGIN TO RECOVER MONDAY...AND CONTINUE TO WARM
THOUGH THURSDAY. IN FACT BY THURSDAY MODELS ARE SUGGESTING +15C OVER
THE AREA...WHICH WOULD PUT HIGH TEMPERATURES INTO POSSIBLE RECORD
TERRITORY. SO AFTER A COOL START MONDAY...HIGHS MID 30S TO MID
40S...TUESDAY THROUGH THURSDAY LOOKING VERY MILD. COULD BE PUSHING
60 DEGREES OR WARMER AGAIN BY THURSDAY.
AVIATION...
MID AND HIGH LEVEL CLOUDS WILL CONTINUE ACROSS WESTERN
AND NORTH CENTRAL NEBRASKA THIS AFTERNOON...WITH SKIES CLEARING
TONIGHT. CEILINGS MAY GET AS LOW AS 5000 FT AGL...ALONG WITH A FEW
RAIN SHOWERS...ACROSS NORTH CENTRAL NEBRASKA LATE THIS AFTERNOON AND
EARLY THIS EVENING. VFR EXPECTED TO PREVAIL...WITH GUSTY WEST
WINDS TO 30 KTS WEST OF HIGHWAY 83 FROM LATE AFTERNOON THROUGH THE
EVENING.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM/EXTENDED...WFO LBF
AVIATION...SPRINGER
AREA FORECAST DISCUSSION
NWS PUEBLO CO
350 AM MST FRI DEC 30 2011
.SHORT TERM...
(TODAY AND TONIGHT)
CURRENTLY...COLORADO WAS UNDER BRISK NW FLOW ALOFT...WITH SOME MTN
WAVE CLOUDS SHOWING UP ON SATELLITE OVER THE SW MTS AND THE SANGRES.
CONUS IR SATELLITE IMAGERY ALONG WITH H5 RUC ANALYSIS SHOWED THAT
THE NEXT UPPER SHORTWAVE THAT WILL AFFECT THE REGION BEGINNING LATER
TONIGHT WAS JUST MOVING ONSHORE ACROSS THE PAC NW. CLOSER TO
HOME...WINDS HAVE FINALLY DIMINISHED AND DECOUPLED FOR THE LOWER
ELEVATIONS MAKING FOR A WIDE ARRAY OF SFC TEMPS. GENERALLY...AS OF 3
AM TEMPS HAD DROPPED INTO THE 30S TO UPPER 20S FOR MOST
LOCATIONS...AND IN THE SINGLE DIGITS FOR THE SLV.
TODAY...RELATIVELY QUIET AND MILD DAY FOR THE CWA TODAY UNDER
SHORTWAVE RIDGING...WITH TEMPS WARMING INTO THE UPPER 40S AND 50S
FOR THE PLAINS...AND IN THE 40S FOR THE SLV. WINDS ACROSS THE HIGHER
ELEVATIONS WILL START TO PICK UP THROUGH LATE AFTN AS THE UPPER
DISTURBANCE APPROACHES.
TONIGHT...LATEST MODEL RUNS HAVE SEEMED TO SLOW EVERYTHING DOWN BY
ABOUT 6 HRS OR SO...AND ARE NOW PLACING THE AXIS OF THE UPPER
DISTURBANCE OVER W MONTANA AND IDAHO AT 06Z THIS EVE. THE PRES
GRADIENT TIGHTENS AND THE H5 PLAN VIEW PAINTS THE STANDARD HIGH WIND
SIGNATURE. MODEL CROSS SECTIONS DO SHOW ABOUT 55 TO 60 KTS AT MT
TOP...THEN INCREASE TO 70 KTS BY 12Z. INTERESTING THING IS THAT THE
REVERSE SHEAR IS NOW MORE PROMINENT EARLIER IN THE EVENING...WHEN
WINDS ARE NOT FORECAST TO BE AS STRONG...THEN AFTER MIDNIGHT WHEN
WINDS START TO INCREASE THE REVERSE SHEAR DISAPPEARS. WITH THESE
LINGERING QUESTIONS...AND AFTER TALKING TO OUR NEIGHBORS TO THE
NORTH...HAVE DECIDED TO KEEP THE WATCH AS IS FOR NOW.
HOPEFULLY...THE 12Z RUN WILL BE ENLIGHTENING FOR THE NEXT SHIFT.
REGARDLESS...IT WILL GET WINDY ACROSS THE HIGHLIGHT AREAS LATE
TONIGHT THROUGH AT LEAST MIDDAY SAT...BUT WHETHER WINDS WILL MEET
WARNING CRITERIA IS STILL A QUESTION. MOORE
.LONG TERM...
...WINDY SATURDAY...
MAIN CONCERN THIS FCST PERIOD IS WINDS FOR SATURDAY. STRONG
DISTURBANCE WILL MOVE TO THE NORTH OF THE REGION DURING THIS DAY.
STRONG GRADIENT WILL CAUSE STRONG WEST WINDS TO OCCUR DURING THE
LATE MORNING AND AFTERNOON. STRONGEST WINDS WILL OCCUR OVER THE
HIGHER ELEVATIONS OF THE MTNS AND ACROSS THE N SECTIONS OF THE
PLAINS. AS FOR WIND HILITES...DID NOT MAKE ANY CHANGES ATTM AS
SIMULATIONS SHOW THE STRONGEST FLOW WHERE CURRENT HILITES ARE IN
PLACE. THERE IS A POSSIBILITY THAT WIND HILITES MAY NEED TO BE
EXTENDED A BIT FARTHER SOUTH TO COVER PUEBLO...S EL PASO AND
POSSIBLY KIOWA COUNTY...AND WILL MAKE THE DAY SHIFT AWARE OF THIS
WHEN THEY ARRIVE LATER THIS MORNING.
FLOW RAPIDLY DECREASES LATE IN THE DAY ACROSS MOST OF THE REGION
EXCEPT THE FAR NE PLAINS. WINDS ARE FCST TO BE NEAR CALM BY 00Z
SUNDAY OVER THE I-25 CORRIDOR REGION ON BOTH THE GFS AND NAM.
WX AFTER SAT WILL BE RATHER TRANQUIL. A WEAK DISTURBANCE WILL MOVE
ACROSS THE REGION DURING THE MID WEEK TIME FRAME...WED-ISH...BUT
THIS SYSTEM APPEARS TO BE DRY WITH ONLY A SLIGHT COOLING. THE NEXT
CHANCE OF ANY PRECIP WILL LIKELY BE NEXT WEEKEND. /HODANISH
&&
.AVIATION...
VFR CONDITIONS EXPECTED AT THE THREE MAIN TAF SITES OF KCOS...KPUB
AND KALS FOR THE NEXT 24 HRS. HOWEVER...WINDS ALOFT WILL STAY BRISK
THROUGH THE DAY. 700 MB WINDS WILL BEGIN TO STRENGTHEN TONIGHT AFTER
06Z AND BE WNW 50 KTS...WITH 70 KTS AND POTENTIALLY HIGHER AT MTN
TOP EXPECTED. THIS WILL CAUSE BLOWING SNOW AND SOME RESTRICTED VSBLY
OVER THE PASSES LATE TONIGHT.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WATCH FROM SATURDAY MORNING THROUGH SATURDAY AFTERNOON
FOR COZ077-078-083-084.
HIGH WIND WATCH FROM LATE TONIGHT THROUGH SATURDAY AFTERNOON FOR
COZ072-073-075-076-079>082.
&&
$$
27/34
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
813 AM CST FRI DEC 30 2011
.UPDATE...
SFC LOW IS NOW MOVING INTO KEOKUK COUNTY BASED ON A WEST WIND AT
KOOA. SFC LOW IS 1MB DEEPER THAN DEPICTED BY THE RUC. PRESSURE
FALLS INDICATE THE SFC LOW WILL CONTINUE MOVING JUST SOUTH OF EAST
AND SHOULD PASS BETWEEN KPIA AND KC75 EARLY THIS AFTERNOON.
BASED ON SFC AND 925MB WBZ TEMPERATURES ANY RASN MIX IS GENERALLY
ALONG AND NORTH OF A KOLZ TO KUGN LINE. RUC TRENDS INDICATE A
CHANGE OVER TO ALL RAIN IS COMPLETE. THE QUESTION IS WHAT HAPPENS
WITH PTYPE LATER THIS MORNING AND AFTERNOON SINCE THE LOW IS
SLIGHTLY STRONGER THAN PROGGED AND THE FACT AN INVERTED TROF WILL
BE MOVING THROUGH THE AREA.
RUC TRENDS INDICATE 925MB WBZ TEMPERATURES DROPPING BELOW 32 BY
MID DAY OVER THE WESTERN THIRD OF THE CWFA AND ROUGHLY THE WESTERN
HALF BY MID AFTERNOON. SFC WBZ TEMPERATURES HOWEVER REMAIN AT OR
ABOVE 32 DEGREES. MORE IMPORTANTLY...SFC WBZ TEMPERATURES REMAIN
AT 34 DEGREES OR HIGHER ALONG OVER ALL BUT THE NORTHWEST QUADRANT
OF THE CWFA THROUGH MID AFTERNOON. BY LATE AFTERNOON WBZ
TEMPERATURES ARE DROPPING BELOW 34 DEGREES IN THE HWY 20 CORRIDOR
EAST OF DUBUQUE.
ANOTHER CONCERN IS THE INVERTED TROF IN CENTRAL IOWA. SFC OBS SHOW
SNOW IS DEVELOPING WEST OF THE INVERTED TROF WHERE WBZ ARE BELOW
32 DEGREES AT 925MB AND AT OR BELOW 34 DEGREES AT THE SFC.
THUS IS APPEARS THAT A RASN MIX WILL MOVE INTO THE NORTHWEST
QUADRANT OF THE CWFA STARTING LATE THIS MORNING AND CONTINUING
INTO THE AFTERNOON. THERE MAY OR MAY NOT BE A COMPLETE CHANGE OVER
IN THIS AREA BUT FCST SOUNDINGS DO SUPPORT A CHANGE OVER TO ALL
SNOW. BY LATE AFTERNOON A RASN MIX SHOULD DEVELOP IN THE HWY 20
CORRIDOR FROM DUBUQUE ON EAST WITH A CHANGE OVER POSSIBLE.
AN UPDATE REFLECTED ALL THIS WILL BE AVAILABLE SHORTLY.
..08..
&&
.PREV DISCUSSION... /ISSUED 541 AM CST FRI DEC 30 2011/
AVIATION...
SURFACE LOW NEAR KPEA WILL MOV EAST SOUTHEAST AND PASS NEAR KC75
ARND 21Z/30. MVFR TO VFR CONDITIONS WILL BE SEEN AT ALL TAF SITES
WITH BRIEF PERIODS OF IFR LIKELY AT KCID/KDBQ/KMLI. COLD AIR ON
THE BACKSIDE OF THE STORM IS EXPECTED TO ALLOW A RASN MIX AT ALL
TAF SITES AFT 20Z/30 THAT MAY CHANGE TO ALL SN AT KCID/KDBQ. MVFR
CONDITIONS ARND 00Z/31 WILL IMPROVE TO VFR BY 06Z/31.
.08..
PREV DISCUSSION... /ISSUED 316 AM CST FRI DEC 30 2011/
SYNOPSIS...
06Z SFC ANALYSIS HAS A SFC LOW BETWEEN KDNS AND KADU WITH A WARM
FRONT RUNNING EAST TO KC75 AND KPNT. A INVERTED TROF RAN INTO
ANOTHER WARM FRONT IN NORTHEAST SOUTH DAKOTA AND THEN ANOTHER SFC
LOW NORTHEAST OF KBIS. DEW POINTS WERE GENERALLY IN THE 30S WITH
40S FROM THE LOWER MISSISSIPPI VALLEY INTO THE LOWER OHIO VALLEY.
RADAR TRENDS SHOW A BAND OF WAA PRECIPITATION FROM NORTHEAST
IOWA INTO NORTHERN ILLINOIS WITH ANOTHER DEVELOPING FROM CENTRAL
IOWA INTO CENTRAL ILLINOIS.
SHORT TERM...TODAY AND TONIGHT
A COMBINATION OF NOWCASTING TOOLS AND RUC TRENDS WERE USED TO
HANDLE FOR TODAY.
THE RUC 300K THETA SFC IN FORCING AND CONDENSATION PRESSURE
DEFICITS DEPICTS QUITE WELL WHAT IS CURRENTLY GOING ON. THE
INITIAL BAND OF WAA PRECIPITATION WILL ROTATE OUT OF THE CWFA BY
12Z. A NEW BAND OF WAA PRECIPITATION DEVELOPING OVER THE CWFA WILL
MOVE ACROSS THE NORTHERN THIRD OF THE CWFA BETWEEN 6 AND 9 AM. WBZ
TEMPERATURES AT THE SFC AND 925MB RISE THE REMAINDER OF THE NIGHT
AND DURING THE MORNING SO THE PRECIPITATION WILL BE ALL RAIN
EXCEPT IN THE HWY 20 CORRIDOR WHERE A MIX IS EXPECTED TO PERSIST
DURING THE MORNING.
LIFT TOOL INDICATES CONVECTIVE PRECIPITATION DEVELOPING ALONG AND
SOUTH OF I-80 THIS MORNING AND RADAR TRENDS DO SUGGEST THIS IS
OCCURRING.
BY MID DAY THE SFC LOW SHOULD BE OVER THE EASTERN CWFA JUST SOUTH
OF I-80 WITH A DEFORMATION ZONE SETTING UP ACROSS THE NORTHERN
THIRD OF THE CWFA. WBZ TEMPERATURES AT THE SFC AND 925MB FROM MID
DAY THROUGH MID AFTERNOON ARE ABOVE 34 DEGREES SO PRECIPITATION
WILL BE ALL RAIN ACROSS THE CWFA.
WRF TRENDS...ASSUMING THEY ARE CORRECT...INDICATE WBZ TEMPERATURES
DROPPING BACK TO 32 DEGREES OR LOWER FROM 3 TO 6 PM INDICATING A
MIX REDEVELOPING NORTH OF HWY 30 WITH A POSSIBLE CHANGE OVER TO
ALL SNOW IN THE HWY 20 CORRIDOR. SNOW ACCUMULATIONS TODAY ARE
EXPECTED TO BE AN INCH OR LESS.
TONIGHT...WRF TRENDS INDICATE PRECIPITATION LINGERING INTO THE
EVENING HOURS ACROSS THE EASTERN CWFA. WBZ TEMPERATURES INDICATE A
MIX WITH POSSIBLY SOME LIGHT SNOW IN THE HWY 20 CORRIDOR EAST OF
DUBUQUE. HOWEVER...CONDENSATION PRESSURE DEFICITS RISE RAPIDLY
DURING THE EVENING WITH THE FORCING SHUTTING DOWN. THUS ANY SNOW
ACCUMULATION SHOULD BE A DUSTING AT BEST.
08..
LONG TERM...SATURDAY THROUGH THURSDAY...
THE UPS AND DOWNS MORE ASSOCIATED WITH FALL WEATHER WILL DOMINATE
THE EXTENDED FORECAST. SATURDAY SHOULD BE VERY MILD ONCE AGAIN...AS
A VERY STRONG SHORT WAVE DIGS INTO THE PLAINS AND RAPIDLY DROPS THE
SURFACE PRESSURE OVER THE MIDWEST. THIS WILL DRAW SOUTHERLY WINDS UP
OVER THE CWA...WHICH WILL BE MOST CERTAINLY GUSTY AT TIMES. THE DAY
SHOULD SHOULD SEE PASSING MID CLOUDS...BUT WITH THE GUSTY WINDS AND
SEASONALLY DEEP MIXING...IT SEEMS PRUDENT TO GO ABOVE GUIDANCE FOR
HIGHS. THUS...WILL STAY CLOSE TO THE PREVIOUS FORECAST AND GO MID
40S NORTHEAST TO MID 50S SOUTHWEST FOR HIGHS. LOW PRESSURE SHOULD
RAPIDLY SHIFT NORTHEAST INTO THE GREAT LAKES...WITH STRONG HIGH
PRESSURE RAPIDLY MOVING INTO THE GREAT PLAINS. WINDS JUST ALOFT WILL
INCREASE TO 40 TO 50 KTS FROM THE NORTHWEST...BRINGING IN STRONG CAA
SATURDAY NIGHT AND SUNDAY. WINDS SHOULD BE PUSHING ADVISORY DURING
THIS PERIOD...WITH SUSTAINED WINDS EASILY SEEING AROUND 25
MPH...POSSIBLY 30...AND GUSTS OF 40 TO 45 LIKELY. WILL HIGHLIGHT
THIS IN THE HWO. AFTER A SLIGHT TO LOW CHANCE FOR RAIN...POSSIBLY
MIXING WITH SNOW NORTHWEST SATURDAY NIGHT...ALL OF WHICH SEEMS LIGHT
AND NON HAZARDOUS...WE WILL ONCE AGAIN GO INTO A DRY PATTERN THE
REMAINING EXTENDED FORECAST. THUS...THE WIND AND COLD AIR IS THE
MAIN STORY FOLLOWING TODAYS PCPN EVENT. WITH TEMPERATURES ALOFT
CRASHING DOWN INTO THE -12 TO -17 RANGE AT 850MB...WE WILL BE SEEING
THE COLDEST WEATHER IN MANY WEEKS. LOOK FOR SLOWLY FALLING
TEMPERATURES IN THE LOWER TO MID 30S SUNDAY...THEN LOWS IN THE TEENS
SUNDAY NIGHT. TEMPS WILL ONLY LIKELY RISE TO THE LOWER 20S NORTH TO
UPPER 20S SOUTHWEST MONDAY WHICH WILL BE THE COLDEST DAY IN THIS
STRETCH. WHILE SHARPLY COLDER THAN LATELY...THESE TEMPERATURES ARE
CLOSER TO NORMAL THAN THE RECENT MILD TEMPERATURES. A CHILLY NIGHT
MONDAY NIGHT WITH LOWS IN THE 11 TO 18 RANGE FROM NORTH TO SOUTH IS
EXPECTED TO GIVE WAY TO WIDESPREAD MILDER AIR AGAIN NEXT WEEK.
GLOBAL MODELS AGREE ON SHIFTING THE COLD HIGH PRESSURE EAST
TUESDAY...ALLOWING SEVERAL DAYS OF SOUTHWEST FLOW FOR THE MID TO
LATE WEEK. THUS...LOOK FOR ANOTHER STAIR STEP UPWARD ON
TEMPERATURES...LEADING TO ANOTHER MILD WEDNESDAY AND THURSDAY. WE
HAVE GONE WITH MID 30S TO AROUND 40 WEDNESDAY AND AND LOWER TO MID
40S THURSDAY. IT DOES APPEAR THAT WE MAY NEED TO INCREASE THESE
TEMPERATURES EVEN FURTHER...AS WE WILL LIKELY HAVE LITTLE MIDWESTERN
SNOW COVER AROUND TO HOLD SHALLOW COLD AIR IN PLACE.
ERVIN..
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
541 AM CST FRI DEC 30 2011
.AVIATION...
SURFACE LOW NEAR KPEA WILL MOV EAST SOUTHEAST AND PASS NEAR KC75
ARND 21Z/30. MVFR TO VFR CONDITIONS WILL BE SEEN AT ALL TAF SITES
WITH BRIEF PERIODS OF IFR LIKELY AT KCID/KDBQ/KMLI. COLD AIR ON
THE BACKSIDE OF THE STORM IS EXPECTED TO ALLOW A RASN MIX AT ALL
TAF SITES AFT 20Z/30 THAT MAY CHANGE TO ALL SN AT KCID/KDBQ. MVFR
CONDITIONS ARND 00Z/31 WILL IMPROVE TO VFR BY 06Z/31.
..08..
&&
.PREV DISCUSSION... /ISSUED 316 AM CST FRI DEC 30 2011/
SYNOPSIS...
06Z SFC ANALYSIS HAS A SFC LOW BETWEEN KDNS AND KADU WITH A WARM
FRONT RUNNING EAST TO KC75 AND KPNT. A INVERTED TROF RAN INTO
ANOTHER WARM FRONT IN NORTHEAST SOUTH DAKOTA AND THEN ANOTHER SFC
LOW NORTHEAST OF KBIS. DEW POINTS WERE GENERALLY IN THE 30S WITH
40S FROM THE LOWER MISSISSIPPI VALLEY INTO THE LOWER OHIO VALLEY.
RADAR TRENDS SHOW A BAND OF WAA PRECIPITATION FROM NORTHEAST
IOWA INTO NORTHERN ILLINOIS WITH ANOTHER DEVELOPING FROM CENTRAL
IOWA INTO CENTRAL ILLINOIS.
SHORT TERM...TODAY AND TONIGHT
A COMBINATION OF NOWCASTING TOOLS AND RUC TRENDS WERE USED TO
HANDLE FOR TODAY.
THE RUC 300K THETA SFC IN FORCING AND CONDENSATION PRESSURE
DEFICITS DEPICTS QUITE WELL WHAT IS CURRENTLY GOING ON. THE
INITIAL BAND OF WAA PRECIPITATION WILL ROTATE OUT OF THE CWFA BY
12Z. A NEW BAND OF WAA PRECIPITATION DEVELOPING OVER THE CWFA WILL
MOVE ACROSS THE NORTHERN THIRD OF THE CWFA BETWEEN 6 AND 9 AM. WBZ
TEMPERATURES AT THE SFC AND 925MB RISE THE REMAINDER OF THE NIGHT
AND DURING THE MORNING SO THE PRECIPITATION WILL BE ALL RAIN
EXCEPT IN THE HWY 20 CORRIDOR WHERE A MIX IS EXPECTED TO PERSIST
DURING THE MORNING.
LIFT TOOL INDICATES CONVECTIVE PRECIPITATION DEVELOPING ALONG AND
SOUTH OF I-80 THIS MORNING AND RADAR TRENDS DO SUGGEST THIS IS
OCCURRING.
BY MID DAY THE SFC LOW SHOULD BE OVER THE EASTERN CWFA JUST SOUTH
OF I-80 WITH A DEFORMATION ZONE SETTING UP ACROSS THE NORTHERN
THIRD OF THE CWFA. WBZ TEMPERATURES AT THE SFC AND 925MB FROM MID
DAY THROUGH MID AFTERNOON ARE ABOVE 34 DEGREES SO PRECIPITATION
WILL BE ALL RAIN ACROSS THE CWFA.
WRF TRENDS...ASSUMING THEY ARE CORRECT...INDICATE WBZ TEMPERATURES
DROPPING BACK TO 32 DEGREES OR LOWER FROM 3 TO 6 PM INDICATING A
MIX REDEVELOPING NORTH OF HWY 30 WITH A POSSIBLE CHANGE OVER TO
ALL SNOW IN THE HWY 20 CORRIDOR. SNOW ACCUMULATIONS TODAY ARE
EXPECTED TO BE AN INCH OR LESS.
TONIGHT...WRF TRENDS INDICATE PRECIPITATION LINGERING INTO THE
EVENING HOURS ACROSS THE EASTERN CWFA. WBZ TEMPERATURES INDICATE A
MIX WITH POSSIBLY SOME LIGHT SNOW IN THE HWY 20 CORRIDOR EAST OF
DUBUQUE. HOWEVER...CONDENSATION PRESSURE DEFICITS RISE RAPIDLY
DURING THE EVENING WITH THE FORCING SHUTTING DOWN. THUS ANY SNOW
ACCUMULATION SHOULD BE A DUSTING AT BEST.
.08..
LONG TERM...SATURDAY THROUGH THURSDAY...
THE UPS AND DOWNS MORE ASSOCIATED WITH FALL WEATHER WILL DOMINATE
THE EXTENDED FORECAST. SATURDAY SHOULD BE VERY MILD ONCE AGAIN...AS
A VERY STRONG SHORT WAVE DIGS INTO THE PLAINS AND RAPIDLY DROPS THE
SURFACE PRESSURE OVER THE MIDWEST. THIS WILL DRAW SOUTHERLY WINDS UP
OVER THE CWA...WHICH WILL BE MOST CERTAINLY GUSTY AT TIMES. THE DAY
SHOULD SHOULD SEE PASSING MID CLOUDS...BUT WITH THE GUSTY WINDS AND
SEASONALLY DEEP MIXING...IT SEEMS PRUDENT TO GO ABOVE GUIDANCE FOR
HIGHS. THUS...WILL STAY CLOSE TO THE PREVIOUS FORECAST AND GO MID
40S NORTHEAST TO MID 50S SOUTHWEST FOR HIGHS. LOW PRESSURE SHOULD
RAPIDLY SHIFT NORTHEAST INTO THE GREAT LAKES...WITH STRONG HIGH
PRESSURE RAPIDLY MOVING INTO THE GREAT PLAINS. WINDS JUST ALOFT WILL
INCREASE TO 40 TO 50 KTS FROM THE NORTHWEST...BRINGING IN STRONG CAA
SATURDAY NIGHT AND SUNDAY. WINDS SHOULD BE PUSHING ADVISORY DURING
THIS PERIOD...WITH SUSTAINED WINDS EASILY SEEING AROUND 25
MPH...POSSIBLY 30...AND GUSTS OF 40 TO 45 LIKELY. WILL HIGHLIGHT
THIS IN THE HWO. AFTER A SLIGHT TO LOW CHANCE FOR RAIN...POSSIBLY
MIXING WITH SNOW NORTHWEST SATURDAY NIGHT...ALL OF WHICH SEEMS LIGHT
AND NON HAZARDOUS...WE WILL ONCE AGAIN GO INTO A DRY PATTERN THE
REMAINING EXTENDED FORECAST. THUS...THE WIND AND COLD AIR IS THE
MAIN STORY FOLLOWING TODAYS PCPN EVENT. WITH TEMPERATURES ALOFT
CRASHING DOWN INTO THE -12 TO -17 RANGE AT 850MB...WE WILL BE SEEING
THE COLDEST WEATHER IN MANY WEEKS. LOOK FOR SLOWLY FALLING
TEMPERATURES IN THE LOWER TO MID 30S SUNDAY...THEN LOWS IN THE TEENS
SUNDAY NIGHT. TEMPS WILL ONLY LIKELY RISE TO THE LOWER 20S NORTH TO
UPPER 20S SOUTHWEST MONDAY WHICH WILL BE THE COLDEST DAY IN THIS
STRETCH. WHILE SHARPLY COLDER THAN LATELY...THESE TEMPERATURES ARE
CLOSER TO NORMAL THAN THE RECENT MILD TEMPERATURES. A CHILLY NIGHT
MONDAY NIGHT WITH LOWS IN THE 11 TO 18 RANGE FROM NORTH TO SOUTH IS
EXPECTED TO GIVE WAY TO WIDESPREAD MILDER AIR AGAIN NEXT WEEK.
GLOBAL MODELS AGREE ON SHIFTING THE COLD HIGH PRESSURE EAST
TUESDAY...ALLOWING SEVERAL DAYS OF SOUTHWEST FLOW FOR THE MID TO
LATE WEEK. THUS...LOOK FOR ANOTHER STAIR STEP UPWARD ON
TEMPERATURES...LEADING TO ANOTHER MILD WEDNESDAY AND THURSDAY. WE
HAVE GONE WITH MID 30S TO AROUND 40 WEDNESDAY AND AND LOWER TO MID
40S THURSDAY. IT DOES APPEAR THAT WE MAY NEED TO INCREASE THESE
TEMPERATURES EVEN FURTHER...AS WE WILL LIKELY HAVE LITTLE MIDWESTERN
SNOW COVER AROUND TO HOLD SHALLOW COLD AIR IN PLACE.
.ERVIN..
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
958 AM EST FRI DEC 30 2011
.SYNOPSIS...
LOW PRESSURE WILL STRENGTHEN OVER THE CENTRAL MIDWEST REGION THROUGH
TONIGHT...BEFORE MOVING INTO NEW ENGLAND ON SATURDAY. A COLD
FRONT WILL CROSS THE REGION SATURDAY MORNING. HIGH PRESSURE WILL
RETURN TO THE REGION SATURDAY NIGHT BEFORE MOVING OFF THE COAST
SUNDAY. A STRONG COLD FRONT WILL ARRIVE LATE SUNDAY NIGHT AND WILL
USHER IN BLUSTERY ARCTIC AIR MONDAY NIGHT.
&&
.NEAR TERM /THROUGH TONIGHT/...
LATEST WV SAT LOOP SHOWS AN UPPER LOW SPINNING OVER ERN IA THIS
MRNG. A POTENT ULVL JET STREAK DIGGING ON THE WRN SIDE OF THE LOW
WILL LEAD TO AMPLIFICATION OF THE TROUGH AS IT MOVES TOWARD THE
OH VLY BY LATE TDA. SYNOPTIC-SCALE FLOW AHEAD OF THE LOW WILL
BACK AND STRENGTHEN OVER THE ERN CONUS. DOWNSTREAM IMPACTS IN THE
MID-ATLANTIC FROM THE DEVELOPING S-SW FLOW INCLUDE ADVECTION OF
MILDER AIR AND AN INCREASE IN MID-HI CLOUDS THRUOUT THE DAY. CLOUD
COVER WILL VARY ACROSS THE CWA...BUT ON AVG WILL RANGE FROM PARTLY
SUNNY ACROSS SRN MD TO CLOUDY ALONG THE ALLEGHENY FRONT. DESPITE
LIMITED DAYTIME HEATING FROM THE CLOUD COVER...MAX TEMPS WILL
STILL REACH THE LOW/MID 50S AS A WARM AIRMASS IS IN PLACE /12Z IAD
RAOB SHOWS 9C LAYER AT THE TOP OF THE NOCTURNAL INVERSION/.
LATEST RADAR LOOP OVERLAID WITH RUC ANALYSIS SHOWS LGT RETURNS
CROSSING THE APPALACHIANS IN ASSOCIATION WITH A BAND OF LOW-MID
LVL ISENTROPIC LIFT/CONVERGENCE WELL AHEAD OF THE LOW AND IN THE
LEFT-EXIT REGION OF AN UPPER JET STREAK. HAVE ADDED ISO LGT RAIN
SHOWERS AND SPRINKLES INTO THE FCST FOR THE POTOMAC HIGHLANDS
FROM LATE THIS MRNG THRU THE ERY AFTN.
TONIGHT...UPR TROUGH ASSOCIATED WITH THE MIDWEST LOW CROSSES THE CWA
AFTER MIDNIGHT. DPVA ASSOCIATED WITH THIS TROUGH WILL PRODUCE LOW/MID-
LEVEL CLOUDS. THEREFORE...LOW CHANCES FOR LIGHT RAIN SHOWERS WERE
EXPANDED ACROSS THE CWA. HOWEVER...LIMITED MOISTURE AND
DOWNSLOPING LOW-LEVEL FLOW WILL KEEP ANY DEVELOPMENT AS
LIGHT/SPRINKLES. LIKELY POPS FOR THE FAR WRN SLOPES OF THE
HIGHLANDS. MILD NIGHT FOR LATE DECEMBER...WITH SLY FLOW AND
CLOUDS...SO PTYPE TNGT WILL BE RAIN. MIN TEMPS MID/UPPER 30S WEST
OF THE BLUE RIDGE...UPR 30S TO LOW 40S EAST /IN URBAN AND NEAR-
SHORE LOCALES/...ABOUT 10 DEGREES ABOVE NORMAL.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY/...
UPR RDG WILL BE FOUND OVER MID-ATLC RGN ON SAT. SHRTWV TROF OVER
CNTRL PLNS AND A SECOND SHRTWV TROF OVER S-CNTRL CANADA WILL PHASE
IN GRTLKS RGN SAT NGT...LEADING TO DP CLOSED LOW OVER MI.
LOW-LVL JET WILL STRENGTHEN OVER MID-ATLC RGN ON SUN IN RESPONSE
TO STRENGTHENING LOW IN GRTLKS. WARM AIR ADVCTN WILL ENSURE THAT
ANY PCPN ON SUN FALLS AS RAIN. BUT WINDS WILL BCM WLY AND QUITE
GUSTY AS SFC TROF CROSSES THE RGN. BY LATE AFTN...COLDER AIR MAY
BE BANKED AGAINST THE APLCNS.
MAXIMA THIS WKEND WILL CONT TO BE QUITE MILD IN THE MID-UPR 50S.
MINIMA SAT NGT WILL BE NR NRML...IN THE LOW-MID 30S.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
CLOSED UPR LOW ON SUN WILL BE LOCATED JUST N OF GRTLKS RGN AND
WILL SPAN MUCH OF THE ERN CONUS. H5 RDG WILL AMPLIFY OVER WRN
CONUS. A SHRTWV TROF WILL MOVE SWD INTO THE CONUS AHD OF THIS RDG
AND WILL DISLODGE ARCTIC AMS. THIS COLD AMS WILL MOVE INTO THE
GRTLKS RGN ON MON AND INTO NEW ENGLAND BY TUE.
MODEST MSTR AHEAD OF THIS APRCHG SHRTWV TROF AND COLD ADVCTN ALOFT
ASSOCIATED WITH THE WAVE WILL LEAD TO SGFNT INSTBY ALONG WRN
SLOPES OF POTOMAC HIGHLANDS FOR A PROLONGED PD MON-TUE MRNG. WITH
MAXIMA XPCD TO RMN BLW FRZG IN THESE ZONES...SGFNT SNOW ACCUMS
XPCD...LKLY WARRANTING WINTER HEADLINES AS THE TIME NRS. WINDS
ALSO WILL BE OF CONCERN DURG THIS EVENT...LEADING TO HAZARDOUS
WIND CHILLS AND POOR VSBYS. ANY PCPN THAT CROSSES THE MTNS WILL BE
VERY LGT OWING TO DOWNSLOPING FLOW.
STRONG COLD ADVCTN WILL OCCUR ON TUE AS ARCTIC AMS OVERTAKES THE
NERN CONUS. H9 TEMPS AS LOW AS 10 TO 15 BLW ZERO COULD LEAD TO
MAXIMA IN THE MID-UPR 20S AND MINIMA IN TEENS...WITH SINGLE DIGIT
TEMPS XPCD AT HIGHER ELEVATIONS. ANY ONGOING SNOW SHWRS ON WRN
SLOPES WILL COME TO AN END AS SFC HIPRES BUILDS INTO THE RGN. SFC
RDG WILL BE LOCATED IN MID- ATLC RGN ON WED.
MAXIMA WERE UNDERCUT BY SVRL DEG F ON TUE. MINIMA TUE NGT IN
PARTICULAR WILL BE VERY COLD AS SFC HIPRES BUILDS.
&&
.AVIATION /14Z FRIDAY THROUGH TUESDAY/...
VFR WITH SLY FLOW 5-10 KT TODAY. MID AND HIGH CLOUDS DURING THE
DAY WILL GRADUALLY LOWER TO 3-6 KFT OVNGT AS A COLD FRONT
APPROACHES FROM THE WEST. SHRA POSSIBLE DURING THIS TIME AS THE
FRONT MOVES THRU. ANY SHOWER ACTIVITY WILL BE ISO AND LGT.
VFR CONDS WILL CONT THRU NEXT WK. BUT SGFNT WIND WILL BE OF
CONCERN TO AVIATION INTERESTS AS SFC TROF AND CDFNT ARRIVE EARLY
NEXT WK. SGFNT TURBULENCE CAN BE ANTICIPATED.
&&
.MARINE...
SLY/SSWLY FLOW INCREASES TODAY AHEAD OF A COLD FRONT THAT MOVES
THRU EARLY SATURDAY. SMALL CRAFT ADVISORY GOES INTO EFFECT AT 2PM
SOUTH OF DRUM PT...THEN UP THE MAIN CHANNEL OF THE BAY /SOUTH OF
POOLES ISLAND/ AND LOWER TIDAL POTOMAC RIVER FOR TONIGHT. MAX
GUSTS EXPECTED AROUND 20 KT.
SMALL CRAFT ADZY WAS EXPANDED TO ALL ZONES ON SAT AS CDFNT CROSSES
THE RGN. WINDS WILL SUBSIDE SAT NGT AS HIPRES BUILDS.
SFC TROF AND SUBSEQUENT CDFNT ASSOCIATED WITH ARCTIC AMS WILL
IMPACT THE WATERS EARLY NEXT WK. SMALL CRAFT ADZY WILL BE NEEDED.
GALE WRNG MAY BE NEEDED DURG THIS TIME.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 6 AM TO 6 PM EST SATURDAY FOR ANZ530-
535-536-538-539-542.
SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO 6 PM EST
SATURDAY FOR ANZ534-543.
SMALL CRAFT ADVISORY FROM 5 PM THIS AFTERNOON TO 6 PM EST
SATURDAY FOR ANZ531>533-537-540-541.
&&
$$
UPDATE...KLEIN
PREV DISC...JACKSON/KRAMAR
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
636 AM EST FRI DEC 30 2011
UPDATED AVIATION DISCUSSION FOR 12Z TAFS
.SYNOPSIS...
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW WNW FLOW ALF OVER
THE GRT LKS BTWN LO AMPLITUDE RDGING OVER THE W AND A TROF N JUST
OFF THE E COAST. SHRTWV RESPONSIBLE FOR SN ON THU IS PUSHING EWD
TOWARD SE ONTARIO...BUT WEAK SFC-H85 TROF REMAINS OVER ERN UPR MI.
BUT WITH DNVA/DEEP LYR QVECTOR DVGC/SUBSIDENCE/DRYING ALF IN THE
WAKE OF THE SHRTWV...THE PCPN OVER THE CWA HAS PRETTY MUCH ENDED.
THE MQT 88D DOES SHOW HIER RADAR RETURNS OVER ECNTRL LK SUP NEAR
WEAK SFC LO CENTER. 00Z INL RAOB SHOWS SHARP INVRN BASE NEAR H875
WITH TEMP JUST BLO THE INVRN DOWN TO -14C...LO ENUF TO SUPPORT LES.
ALTHOUGH THE 00Z INL RAOB INDICATES MODEST DRYING IN THE SUB INVRN
LYR...SKIES ARE GENERALLY CLDY AT MOST LOCATIONS FM THE MN ARROWHEAD
SEWD THRU UPR MI...BUT SOME BREAKS IN THE CLDS ARE EVIDENT. FARTHER
TO THE W/SW IN MN/WI...SKIES ARE MOCLR CLOSER TO WEAK SFC RDG AXIS
ASSOCIATED WITH INCOMING SHRTWV RDG MOVING E THRU MN. ANOTHER PAIR
OF SHRTWVS ARE NOTED IN THE NRN/CNTRL PLAINS...BUT THESE APPEAR TO
BE DIGGING TO THE SE. MUCH FARTHER TO THE W...A STRONG SHRTWV IS
APRCHG THE PAC NW. UPSTREAM HI TEMPS YDAY SUG MAX TEMPS WL GENERALLY
BE ARND 30.
&&
.DISCUSSION...
MAIN FCST CONCERNS THIS PACKAGE SHIFT TO POTENTIAL SN EVENT ON NEW
YEARS DAY/MON RELATED TO SHRTWV NOW APRCHG THE PAC NW.
TDAY...LOOKS LIKE A RELATIVELY QUIET DAY ON TAP WITH WEAK HGT
RISES/DRYING ALF IN THE WAKE OF DEPARTING SHRTWV. SHRTWV COMPLEX IN
THE PLAINS IS FCST TO CONSOLIDATE IN THE LOWER GRT LKS...WITH
ACCOMPANYING DEEP LYR QVECTOR CNVGC/PCPN PASSING S OF UPR MI. FCST
SDNGS SHOW INVRN BASE SINKING TO H9-925 OVER THE CWA IN THE AFTN...
WITH INVRN BASE TEMPS NO LOWER THAN ABOUT -8C. CONSIDERING
THE WEAK SFC WINDS FCST THAT WOULD NOT SUPPORT ORGANIZATION OF LES
BANDS...THE MARGINAL NATURE OF THE CHILL/DGZ ABV THE SUB INVRN
LYR...AND SOME LLVL DRYING...SUSPECT THERE WL BE LTL IN THE WAKE OF
LES. BUT SINCE THE 00Z INL RAOB DID SHOW -14C AIR AT THE H875 INVRN
BASE AND THE GFS/NAM MODEL ANALYSIS WAS ABOUT 3C TOO WARM AT THAT
SITE...WL MAINTAIN GOING POPS NEAR LK SUP...ESPECIALLY E OFMQT WHERE
WEAK SFC TROF IS FCST TO PERSIST THRU THE DAY. ALSO ADDED A MENTION
OF FZDZ IN THIS AREA WHERE THE LLVL MSTR REMAINS A BIT MORE
RESILIENT AND THE LLVL TEMPS ARE NOT LIKELY TO BE AS LO AS OBSVD AT
INL.
TNGT...SHRTWV RDGING WL BE DOMINATING WITH WEAK SFC HI PRES RDG
AXIS BLDG OVHD. MAINTAINED LO CHC POPS IN THE EVNG OVER THE E WHERE
THE SFC LO PRES TROF WL LINGER WHILE SLOWLY WEAKENING WITH TIME.
EXPECT THE LOWEST MIN TEMPS OVER THE INTERIOR SCNTRL WHERE SKIES WL
TREND MOCLR UNDER LIGHT SFC ACYC FLOW.
SAT...AS SHRTWV COMPLEX NOW MOVING TOWARD THE PAC NW SPLITS AND
DEEPENS TROFS IN SCNTRL CAN AND THE CENTRAL PLAINS...INCRSG SW FLOW
WL DVLP OVER THE UPR LKS AND RETURN DEEPER MSTR TO THE UPR LKS. WITH
INITIAL LLVL DRY AIR...RESTRICTED POPS MAINLY ON SAT AFT TO THE NW
HALF OF THE CWA WHERE GUIDANCE SHOWS DEEPER MOISTENING ON CYC SIDE
OF UPR JET AXIS ROTATING NEWD TOWARD THE UPR LKS BY 00Z SUN. SFC
TEMPS ARE PROGGED TO RISE AOA 32 IN THE AFTN AS H85 TEMPS RISE TO
ARND 0C...BUT NAM/SREF FCST WBLB ZERO HGT BLO 500 AGL WITH LINGERING
LLVL DRY AIR SUG VERY LTL CHC RA MAY BE MIXED WITH THE PCPN AT THE
ONSET.
SAT NGT INTO MON...MODELS HAVE BEGUN TO CONVERGE ON A SCENARIO
SHOWING A DEEPENING UPR TROF/SFC LO AS SEPARATE SHRTWVS IN SCNTRL
CAN AND THE CENTRAL PLAINS PHASE. THE GFS IS MOST AGGRESSIVE AT
DEEPENING A CLOSED LO...SHOWING A 984MB SFC LO OVER NRN LK MI BY 12Z
SUN. PER NCEP DISCUSSION...USED A BLEND OF THE INTERMEDIATE STRENGTH
00Z NAM/00Z CNDN/21Z SREF/12Z ECMWF FOR FCST PREPARATION. THESE
MODELS SHOW SFC LO TRACKING ACRS LK SUP/SRN ONTARIO SAT NGT AND
DRAWING ENUF LLVL MSTR OVER UPR MI TO SUPPORT LIKELY POPS UNDER UPR
DVGC ON CYC SIDE OF JET AXIS WHERE 12HR H5 FALLS APRCH 200M. WITH
THE ARRIVAL OF MORE LLVL MSTR OVER THE E...FCST THKNS/WBLB ZERO HGT
SUPPORT AT LEAST A MIX WITH RA IN THAT AREA. ONCE THE LO SHIFTS TO
THE NE LATE SAT NGT/SUN...STRONG NW WINDS WITH H85 WINDS AOA 50KT
ADVECT MUCH COLDER AIR INTO THE UPR LKS...SETTING UP A LK ENHANCED
SN EVENT WITH FCST SDNGS SHOWING DEEP MSTR UNDER LO HGTS AND OMEGA
WITHIN THE LOWERING DGZ AND SHARP CYC FLOW. GUSTY NW WINDS WL ALSO
RESULT IN CONSIDERABLE BLSN. THIS LK ENHANCED SN WL THEN PERSIST
INTO MON BEFORE THE DEEPER MSTR SLOWLY EXITS AND PCPN TENDS TOWARD
PURE LES BY MON NGT. CONSIDERED DOING A WATCH FOR THE NW WIND SN
BELTS...ESPECIALLY OVER THE W WHERE MOST RECENT NCEP GUIDANCE SHOWS
UP TO A FOOT OF SN THRU 12Z MON. BUT SINCE THE BULK OF THE MOST
SGNFT WX WL OCCUR IN THE 5TH TO 7TH PERIODS...OPTED TO ISSUE AN SPS
TO COVER THIS POTENTIAL WINTER STORM.
EXTENDED...LATEST GUIDANCE IN GOOD AGREEMENT SHOWING DEEP UPR TROF
GIVING WAY TO A MORE ZONAL FLOW AFT MID WEEK WITH A WARMING TREND.
DID LOWER FCST MIN TEMPS A FEW DEGREES FM THE ALLBLEND FCST OVER THE
INTERIOR W HALF ON MON NGT GIVEN ARRIVAL OF SFC RDG AXIS/LGT
WINDS/PWAT AS LO AS 0.1 INCH.
&&
.AVIATION /FOR THE 12Z TAF ISSUANCE/...
LIGHT LOW-LEVEL WIND REGIME THRU THIS FCST PERIOD SUGGESTS
CONDITIONS PROBABLY WILL NOT CHANGE MUCH AT KIWD/KCMX/KSAW.
SO...GIVEN THE LOW-LEVEL MOISTURE OVER THE AREA AND GENERAL MVFR
CIGS...MVFR CIGS WILL LIKELY PREVAIL THRU THE FCST PERIOD.
HOWEVER...THERE MAY BE SOME PERIODS WHERE CLOUDS SCATTER OUT OR CIGS
RISE TO VFR AS INDICATED BY CURRENT REGIONAL SFC OBS AND SATELLITE
IMAGERY.
FG AS SAW SHOULD BURN OFF THIS MORNING AS SURFACE TEMPS INCREASE.
FG MAY FORM AT CMX TONIGHT GIVEN ABUNDANT LOW LEVEL MOISTURE...IF
CLOUDS CAN CLEAR OUT ENOUGH. THE EXACT TIMING IS STILL IN QUESTION.
&&
.MARINE /FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE/...
WINDS WILL DIMINISH TODAY AS LOW PRESSURE TROUGH LINGERS OVER LAKE
SUPERIOR. A WEAK RIDGE WILL THEN SLIDE ACROSS LAKE SUPERIOR INTO
SATURDAY BEFORE A STRONG LOW DEVELOPS OVER THE PLAINS AND MOVES
NORTH OF LAKE SUPERIOR FOR NEW YEARS DAY. HIGH END GALES ARE LOOKING
LIKELY FROM THIS SYSTEM...BEGINNING ON NEW YEARS DAY AND CONTINUING
THROUGH MONDAY AS COLDER AIR PLOWS INTO THE GREAT LAKES. HEAVY
FREEZING SPRAY ALSO MAY OCCUR SUNDAY NIGHT INTO MONDAY. GALE AND
HEAVY FREEZING SPRAY WATCHES WILL LIKELY NEED TO BE ISSUED IN THE
NEXT COUPLE DAYS. WINDS DIMINISH SIGNIFICANTLY BY NEXT TUESDAY WITH
ARRIVAL OF HIGH PRESSURE RIDGE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...KC
DISCUSSION...KC
AVIATION...TITUS
MARINE...TITUS
AREA FORECAST DISCUSSION...UPDATED
NWS PUEBLO CO
1122 AM MST FRI DEC 30 2011
.UPDATE...
UPDATED TO BOOST TEMPERATURES IN THE LEE OF THE MTS WHERE READINGS
ALREADY APPROACHING FCST HIGHS OF MID 50S. COULD SEE A RIBBON OF 60
DEGREE READINGS IN THESE AREAS. ALSO FINE TUNED WIND GRIDS IN THE
UPPER ARKANSAS RIVER AND NRN EL PASO COUNTY WHERE GUSTY SOUTHWEST
WINDS HAVE ALREADY MIXED DOWN THE SURFACE.
AS FOR HIGH WIND HIGHLIGHTS LATER TONIGHT INTO SATURDAY...WILL
LIKELY BE TAKING MOST OF THE AREA TO WARNINGS WITH NEXT FORECAST
UPDATE/ISSUANCE. MTN TOP WINDS INCREASE TO 50-60 KTS
OVERNIGHT...AND TO 65 TO 70 KTS BY SATURDAY MORNING WHICH SHOULD
EASILY MEET HIGH WIND CRITERIA FOR THE ZONES ABOVE 11KFT. WILL
PROBABLY ADD HIGHER ELEVATIONS OF CHAFFEE/LAKE COUNTIES AS
WELL...WHERE STRONG WINDS WILL LIKELY CAUSE BLOWING SNOW ISSUES. CHALLENGE
WILL BE HOW FAR DOWN THE SLOPES THE STRONGEST WINDS WILL DESCEND.
IT WILL BE WINDY ALL AREAS TOMORROW...HOWEVER MTN WAVE PARAMETERS
ARE NOT THAT FAVORABLE. BUT WITH STRONG DOWNWARD FORCING MOVING
ACROSS THE AREA SAT MORNING BEHIND TROF AXIS...NAM12 HAS 50 KT
WINDS DESCENDING TO 800 MB ACROSS PORTIONS OF PUEBLO...AND KIOWA
COUNTIES. MIXING SHOULD BE DEEP ENOUGH TO TAP THESE WINDS FOR
POTENTIAL WIND GUSTS. WILL WAIT FOR LOCAL 4 KM WRF MODEL RUN
BEFORE DECIDING TO THROW IN THESE ZONES ALONG WITH SRN EL PASO
COUNTY INTO HIGHLIGHT AREA. -KT
&&
.PREV DISCUSSION... /ISSUED 1041 AM MST FRI DEC 30 2011/
AVIATION...
LIGHT SOUTHEAST WINDS WILL PERSIST THROUGH THE EARLY AFTERNOON FOR KCOS
AND KPUB BEFORE WINDS INCREASE FROM THE SOUTH TO SOUTHWEST 10-15
KTS. WINDS AT KCOS WILL SHIFT AROUND FROM THE NORTH BY EARLY
EVENING...WITH KPUB MAINTAINING A WEST WIND AROUND 10KTS THROUGH
THE OVERNIGHT HOURS. AT THIS TIME...WITHOUT STRONG MTN WAVE
PARAMETERS IN PLACE...THINK ANY LOW LEVEL WIND SHEAR WILL STAY TO
THE WEST OF THE TAF SITES...BUT THIS WILL HAVE TO BE MONITORED
CLOSELY OVERNIGHT...ESPECIALLY AT KCOS. EXPECT THAT WINDS WILL
INCREASE ABRUPTLY AT KCOS AROUND 15Z ON SAT...AND AT 16-17Z AT
KPUB WITH GUSTS TO AROUND 40 KTS. WINDS WILL REMAIN LIGHT AT KALS
THROUGH THE PERIOD. GUSTY WINDS AT MTN TOP LEVELS ALONG WITH A
ROUND OF SNOW TOMORROW MORNING WILL PRODUCE MTN OBSCURATIONS AT
TIMES WITH BLOWING SNOW. WINDS AT MTN TOP LEVEL WILL BE SUSTAINED
AROUND 50-60 KTS STARTING AROUND 06Z TONIGHT AND CONTINUING
THROUGH TOMORROW. -KT
PREV DISCUSSION... /ISSUED 350 AM MST FRI DEC 30 2011/
SHORT TERM...
(TODAY AND TONIGHT)
CURRENTLY...COLORADO WAS UNDER BRISK NW FLOW ALOFT...WITH SOME MTN
WAVE CLOUDS SHOWING UP ON SATELLITE OVER THE SW MTS AND THE SANGRES.
CONUS IR SATELLITE IMAGERY ALONG WITH H5 RUC ANALYSIS SHOWED THAT
THE NEXT UPPER SHORTWAVE THAT WILL AFFECT THE REGION BEGINNING LATER
TONIGHT WAS JUST MOVING ONSHORE ACROSS THE PAC NW. CLOSER TO
HOME...WINDS HAVE FINALLY DIMINISHED AND DECOUPLED FOR THE LOWER
ELEVATIONS MAKING FOR A WIDE ARRAY OF SFC TEMPS. GENERALLY...AS OF 3
AM TEMPS HAD DROPPED INTO THE 30S TO UPPER 20S FOR MOST
LOCATIONS...AND IN THE SINGLE DIGITS FOR THE SLV.
TODAY...RELATIVELY QUIET AND MILD DAY FOR THE CWA TODAY UNDER
SHORTWAVE RIDGING...WITH TEMPS WARMING INTO THE UPPER 40S AND 50S
FOR THE PLAINS...AND IN THE 40S FOR THE SLV. WINDS ACROSS THE HIGHER
ELEVATIONS WILL START TO PICK UP THROUGH LATE AFTN AS THE UPPER
DISTURBANCE APPROACHES.
TONIGHT...LATEST MODEL RUNS HAVE SEEMED TO SLOW EVERYTHING DOWN BY
ABOUT 6 HRS OR SO...AND ARE NOW PLACING THE AXIS OF THE UPPER
DISTURBANCE OVER W MONTANA AND IDAHO AT 06Z THIS EVE. THE PRES
GRADIENT TIGHTENS AND THE H5 PLAN VIEW PAINTS THE STANDARD HIGH WIND
SIGNATURE. MODEL CROSS SECTIONS DO SHOW ABOUT 55 TO 60 KTS AT MT
TOP...THEN INCREASE TO 70 KTS BY 12Z. INTERESTING THING IS THAT THE
REVERSE SHEAR IS NOW MORE PROMINENT EARLIER IN THE EVENING...WHEN
WINDS ARE NOT FORECAST TO BE AS STRONG...THEN AFTER MIDNIGHT WHEN
WINDS START TO INCREASE THE REVERSE SHEAR DISAPPEARS. WITH THESE
LINGERING QUESTIONS...AND AFTER TALKING TO OUR NEIGHBORS TO THE
NORTH...HAVE DECIDED TO KEEP THE WATCH AS IS FOR NOW.
HOPEFULLY...THE 12Z RUN WILL BE ENLIGHTENING FOR THE NEXT SHIFT.
REGARDLESS...IT WILL GET WINDY ACROSS THE HIGHLIGHT AREAS LATE
TONIGHT THROUGH AT LEAST MIDDAY SAT...BUT WHETHER WINDS WILL MEET
WARNING CRITERIA IS STILL A QUESTION. 27
LONG TERM...
.WINDY SATURDAY...
MAIN CONCERN THIS FCST PERIOD IS WINDS FOR SATURDAY. STRONG
DISTURBANCE WILL MOVE TO THE NORTH OF THE REGION DURING THIS DAY.
STRONG GRADIENT WILL CAUSE STRONG WEST WINDS TO OCCUR DURING THE
LATE MORNING AND AFTERNOON. STRONGEST WINDS WILL OCCUR OVER THE
HIGHER ELEVATIONS OF THE MTNS AND ACROSS THE N SECTIONS OF THE
PLAINS. AS FOR WIND HILITES...DID NOT MAKE ANY CHANGES ATTM AS
SIMULATIONS SHOW THE STRONGEST FLOW WHERE CURRENT HILITES ARE IN
PLACE. THERE IS A POSSIBILITY THAT WIND HILITES MAY NEED TO BE
EXTENDED A BIT FARTHER SOUTH TO COVER PUEBLO...S EL PASO AND
POSSIBLY KIOWA COUNTY...AND WILL MAKE THE DAY SHIFT AWARE OF THIS
WHEN THEY ARRIVE LATER THIS MORNING.
FLOW RAPIDLY DECREASES LATE IN THE DAY ACROSS MOST OF THE REGION
EXCEPT THE FAR NE PLAINS. WINDS ARE FCST TO BE NEAR CALM BY 00Z
SUNDAY OVER THE I-25 CORRIDOR REGION ON BOTH THE GFS AND NAM.
WX AFTER SAT WILL BE RATHER TRANQUIL. A WEAK DISTURBANCE WILL MOVE
ACROSS THE REGION DURING THE MID WEEK TIME FRAME...WED-ISH...BUT
THIS SYSTEM APPEARS TO BE DRY WITH ONLY A SLIGHT COOLING. THE NEXT
CHANCE OF ANY PRECIP WILL LIKELY BE NEXT WEEKEND. /34
AVIATION...
VFR CONDITIONS EXPECTED AT THE THREE MAIN TAF SITES OF KCOS...KPUB
AND KALS FOR THE NEXT 24 HRS. HOWEVER...WINDS ALOFT WILL STAY BRISK
THROUGH THE DAY. 700 MB WINDS WILL BEGIN TO STRENGTHEN TONIGHT AFTER
06Z AND BE WNW 50 KTS...WITH 70 KTS AND POTENTIALLY HIGHER AT MTN
TOP EXPECTED. THIS WILL CAUSE BLOWING SNOW AND SOME RESTRICTED VSBLY
OVER THE PASSES LATE TONIGHT.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WATCH FROM SATURDAY MORNING THROUGH SATURDAY AFTERNOON
FOR COZ077-078-083-084.
HIGH WIND WATCH FROM LATE TONIGHT THROUGH SATURDAY AFTERNOON FOR
COZ072-073-075-076-079>082.
&&
$$
31/23
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1041 AM MST FRI DEC 30 2011
.AVIATION...
LIGHT SOUTHEAST WINDS WILL PERSIST THROUGH THE EARLY AFTERNOON FOR KCOS
AND KPUB BEFORE WINDS INCREASE FROM THE SOUTH TO SOUTHWEST 10-15
KTS. WINDS AT KCOS WILL SHIFT AROUND FROM THE NORTH BY EARLY
EVENING...WITH KPUB MAINTAINING A WEST WIND AROUND 10KTS THROUGH
THE OVERNIGHT HOURS. AT THIS TIME...WITHOUT STRONG MTN WAVE
PARAMETERS IN PLACE...THINK ANY LOW LEVEL WIND SHEAR WILL STAY TO
THE WEST OF THE TAF SITES...BUT THIS WILL HAVE TO BE MONITORED
CLOSELY OVERNIGHT...ESPECIALLY AT KCOS. EXPECT THAT WINDS WILL
INCREASE ABRUPTLY AT KCOS AROUND 15Z ON SAT...AND AT 16-17Z AT
KPUB WITH GUSTS TO AROUND 40 KTS. WINDS WILL REMAIN LIGHT AT KALS
THROUGH THE PERIOD. GUSTY WINDS AT MTN TOP LEVELS ALONG WITH A
ROUND OF SNOW TOMORROW MORNING WILL PRODUCE MTN OBSCURATIONS AT
TIMES WITH BLOWING SNOW. WINDS AT MTN TOP LEVEL WILL BE SUSTAINED
AROUND 50-60 KTS STARTING AROUND 06Z TONIGHT AND CONTINUING
THROUGH TOMORROW. -KT
&&
.PREV DISCUSSION... /ISSUED 350 AM MST FRI DEC 30 2011/
SHORT TERM...
(TODAY AND TONIGHT)
CURRENTLY...COLORADO WAS UNDER BRISK NW FLOW ALOFT...WITH SOME MTN
WAVE CLOUDS SHOWING UP ON SATELLITE OVER THE SW MTS AND THE SANGRES.
CONUS IR SATELLITE IMAGERY ALONG WITH H5 RUC ANALYSIS SHOWED THAT
THE NEXT UPPER SHORTWAVE THAT WILL AFFECT THE REGION BEGINNING LATER
TONIGHT WAS JUST MOVING ONSHORE ACROSS THE PAC NW. CLOSER TO
HOME...WINDS HAVE FINALLY DIMINISHED AND DECOUPLED FOR THE LOWER
ELEVATIONS MAKING FOR A WIDE ARRAY OF SFC TEMPS. GENERALLY...AS OF 3
AM TEMPS HAD DROPPED INTO THE 30S TO UPPER 20S FOR MOST
LOCATIONS...AND IN THE SINGLE DIGITS FOR THE SLV.
TODAY...RELATIVELY QUIET AND MILD DAY FOR THE CWA TODAY UNDER
SHORTWAVE RIDGING...WITH TEMPS WARMING INTO THE UPPER 40S AND 50S
FOR THE PLAINS...AND IN THE 40S FOR THE SLV. WINDS ACROSS THE HIGHER
ELEVATIONS WILL START TO PICK UP THROUGH LATE AFTN AS THE UPPER
DISTURBANCE APPROACHES.
TONIGHT...LATEST MODEL RUNS HAVE SEEMED TO SLOW EVERYTHING DOWN BY
ABOUT 6 HRS OR SO...AND ARE NOW PLACING THE AXIS OF THE UPPER
DISTURBANCE OVER W MONTANA AND IDAHO AT 06Z THIS EVE. THE PRES
GRADIENT TIGHTENS AND THE H5 PLAN VIEW PAINTS THE STANDARD HIGH WIND
SIGNATURE. MODEL CROSS SECTIONS DO SHOW ABOUT 55 TO 60 KTS AT MT
TOP...THEN INCREASE TO 70 KTS BY 12Z. INTERESTING THING IS THAT THE
REVERSE SHEAR IS NOW MORE PROMINENT EARLIER IN THE EVENING...WHEN
WINDS ARE NOT FORECAST TO BE AS STRONG...THEN AFTER MIDNIGHT WHEN
WINDS START TO INCREASE THE REVERSE SHEAR DISAPPEARS. WITH THESE
LINGERING QUESTIONS...AND AFTER TALKING TO OUR NEIGHBORS TO THE
NORTH...HAVE DECIDED TO KEEP THE WATCH AS IS FOR NOW.
HOPEFULLY...THE 12Z RUN WILL BE ENLIGHTENING FOR THE NEXT SHIFT.
REGARDLESS...IT WILL GET WINDY ACROSS THE HIGHLIGHT AREAS LATE
TONIGHT THROUGH AT LEAST MIDDAY SAT...BUT WHETHER WINDS WILL MEET
WARNING CRITERIA IS STILL A QUESTION. 27
LONG TERM...
..WINDY SATURDAY...
MAIN CONCERN THIS FCST PERIOD IS WINDS FOR SATURDAY. STRONG
DISTURBANCE WILL MOVE TO THE NORTH OF THE REGION DURING THIS DAY.
STRONG GRADIENT WILL CAUSE STRONG WEST WINDS TO OCCUR DURING THE
LATE MORNING AND AFTERNOON. STRONGEST WINDS WILL OCCUR OVER THE
HIGHER ELEVATIONS OF THE MTNS AND ACROSS THE N SECTIONS OF THE
PLAINS. AS FOR WIND HILITES...DID NOT MAKE ANY CHANGES ATTM AS
SIMULATIONS SHOW THE STRONGEST FLOW WHERE CURRENT HILITES ARE IN
PLACE. THERE IS A POSSIBILITY THAT WIND HILITES MAY NEED TO BE
EXTENDED A BIT FARTHER SOUTH TO COVER PUEBLO...S EL PASO AND
POSSIBLY KIOWA COUNTY...AND WILL MAKE THE DAY SHIFT AWARE OF THIS
WHEN THEY ARRIVE LATER THIS MORNING.
FLOW RAPIDLY DECREASES LATE IN THE DAY ACROSS MOST OF THE REGION
EXCEPT THE FAR NE PLAINS. WINDS ARE FCST TO BE NEAR CALM BY 00Z
SUNDAY OVER THE I-25 CORRIDOR REGION ON BOTH THE GFS AND NAM.
WX AFTER SAT WILL BE RATHER TRANQUIL. A WEAK DISTURBANCE WILL MOVE
ACROSS THE REGION DURING THE MID WEEK TIME FRAME...WED-ISH...BUT
THIS SYSTEM APPEARS TO BE DRY WITH ONLY A SLIGHT COOLING. THE NEXT
CHANCE OF ANY PRECIP WILL LIKELY BE NEXT WEEKEND. /34
AVIATION...
VFR CONDITIONS EXPECTED AT THE THREE MAIN TAF SITES OF KCOS...KPUB
AND KALS FOR THE NEXT 24 HRS. HOWEVER...WINDS ALOFT WILL STAY BRISK
THROUGH THE DAY. 700 MB WINDS WILL BEGIN TO STRENGTHEN TONIGHT AFTER
06Z AND BE WNW 50 KTS...WITH 70 KTS AND POTENTIALLY HIGHER AT MTN
TOP EXPECTED. THIS WILL CAUSE BLOWING SNOW AND SOME RESTRICTED VSBLY
OVER THE PASSES LATE TONIGHT.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WATCH FROM SATURDAY MORNING THROUGH SATURDAY AFTERNOON
FOR COZ077-078-083-084.
HIGH WIND WATCH FROM LATE TONIGHT THROUGH SATURDAY AFTERNOON FOR
COZ072-073-075-076-079>082.
&&
$$
31/23
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1200 PM CST FRI DEC 30 2011
.UPDATE...
STARTING TO GET REPORTS OF THE RAIN TURNING NOW TO LIGHT
SLEET/SNOW AT EDGEWOOD AND STANLEY IN OUR FAR NORTHWEST CWA.
TEMPERATURES THERE HAD DROPPED TO THE FREEZING MARK BUT OBSERVERS
MENTIONED THE SNOW/SLEET WAS MELTING UPON CONTACT WITH THE GROUND.
HOWEVER BE CAREFUL ON BRIDGES/OVERPASSES AS THEY ARE COLDER. ELSEWHERE
ACROSS THE DVN CWA LIGHT RAIN WAS STILL FALLING WITH TEMPERATURES
IN THE MID 30S TO LOWER 40S. HAVE ALREADY UPDATED THE FORECAST TO
REDUCE SNOW ACCUMULATIONS IN OUR FAR NORTHWEST TO LESS THAN ONE-
HALF INCH. RADAR LOOPS SUGGEST PRECIPITATION RETURNS WERE
DIMINISHING AS THE MOISTURE GETS CUT OFF DUE TO THE OCCLUDING
STAGE OF THE CYCLONE THAT IS LOCATED EAST OF GENESEO IL IN HENRY
COUNTY. LATEST RUC STILL INDICATES A TRANSITION TO A MIX OF LIGHT
RAIN AND SNOW ACROSS OUR NORTH AS THE AFTERNOON PROGRESSES WITH
PRECIPITATION ENDING IN OUR IL COUNTIES THIS EVENING.
&&
.AVIATION...
IFR CONDS IN -RA/BR/FG THROUGH THE AFTERNOON WITH THE RAIN
CHANGING TO -SN/-IP AT KDBQ AND POSSIBLY KCID. PRECIPITATION TO
END EARLY THIS EVENING THEN CIGS BECOMING MVFR. SKIES WILL BE
CLEARING OVERNIGHT AS HIGH PRESSURE BUILDS INTO THE AREA. VFR
CONDS EXPECTED ON SATURDAY. NORTHWEST WINDS GUSTING TO 20 KNOTS
THIS AFTERNOON THEN WINDS DIMINISHING TO LESS THAN 10 KNOTS THIS
EVENING. VARIABLE WINDS LESS THAN 5 KNOTS LATE TONIGHT THEN
TURNING SOUTH AND INCREASING TO 15 TO 25 KNOTS BY SATURDAY AFTERNOON.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
HAASE
AREA FORECAST DISCUSSION
NWS CARIBOU ME
415 PM EST FRI DEC 30 2011
.SYNOPSIS...
LOW PRESSURE OVER THE GREAT LAKES WILL WEAKEN TONIGHT WITH
REDEVELOPMENT OFF OF CAPE COD ON SATURDAY. THIS NEW LOW PRESSURE
WILL TRACK EASTWARD THROUGH THE GULF OF MAINE AND THEN SOUTH OF
NOVA SCOTIA BY SATURDAY EVENING. A HIGH PRESSURE RIDGE WILL BUILD
ACROSS THE REGION ON SUNDAY.
&&
.NEAR TERM /THROUGH SATURDAY/...
SHORTWAVE TROUGH FLATTENING UPPER RIDGE ACROSS THE STATE IS
PRODUCING AN AREA OF LIGHT SNOW SHOWERS ACROSS WESTERN MAINE THIS
AFTERNOON. HRRR MODEL INDICATES AS THIS SHORTWAVE TROUGH MOVES
ACROSS DOWNEAST LATE THIS AFTERNOON INTO THIS EVENING, A PERIOD OF
SNOW SHOWERS CAN BE EXPECTED WITH ANY ACCUMULATION LESS THAN AN
INCH.
MODELS IN GOOD AGREEMENT WITH LOW PRESSURE OVER THE GREAT LAKES
FILLING TONIGHT WITH REDEVELOPMENT JUST EAST OF CAPE COD BY SATURDAY
AFTERNOON. THE LOW PRESSURE WILL THEN TRACK EASTWARD AND MOVE SOUTH
OF NOVA SCOTIA BY SATURDAY NIGHT. WITH HIGH PRESSURE EAST OF THE
REGION INSTEAD OF NORTH OF THE STATE, WARM ATLANTIC AIR IN THE
LOWER LEVELS WILL BE ALLOWED TO FLOW NORTHWARD ACROSS THE FORECAST
AREA PRODUCING ANOTHER WINTRY MIX FOR THE REGION. CRITICAL THICKNESS
NOW INDICATING MORE MIX THAN SNOW SO HAVE REDUCE SNOW ACCUMULATION
ACROSS CENTRAL AND NORTHERN SECTIONS BY AROUND AN INCH AND
INCREASE ICE ACCUMULATIONS BY A TENTH OF AN INCH ACROSS CENTRAL
PORTIONS. AT THIS TIME, EXPECT THE AXIS OF HEAVIEST ICE TO OCCUR
30 MILES ON EITHER SIDE OF A LINE FROM GREENVILLE TO HOULTON WHERE
UP TO A QUARTER OF AN INCH MAY ACCUMULATE. MODELS ALSO INDICATING
TEMPERATURES WILL BE SLOW TO RISE ACROSS DOWNEAST SO WILL EXTEND
ADVISORY FROM 7 AM TO NOONTIME SATURDAY.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/...
THINGS WILL BE WINDING DOWN SATURDAY NIGHT AS THE LOW MOVES OUT OF
THE GULF OF MAINE AND SOUTH OF NOVA SCOTIA. THERE WILL BE SOME
LINGERING FREEZING RAIN IN NORTHERN SECTIONS DURING THE EVENING BUT
COLDER AIR WRAPPING AROUND THE DEPARTING SYSTEM WILL CHANGE THE
PRECIPITATION TO ALL SNOW FROM NORTH TO SOUTH THROUGH THE NIGHT.
SNOWFALL AMOUNTS WILL BE LIGHT...GENERALLY A DUSTING TO AROUND HALF
AN INCH WITH ANOTHER TRACE OF ICE ACCUMULATION.
HIGH PRESSURE WILL BRIEFLY BUILD IN SUNDAY BEFORE ANOTHER LOW
PRESSURE SYSTEM MOVES BY TO OUR NORTH SUNDAY NIGHT AND MONDAY. THIS
WILL BRING ANOTHER ROUND OF SNOW AND RAIN TO THE REGION. THE
RAIN/SNOW LINE WILL BE SOUTH OF HOULTON AND MILLINOCKET WITH THE
IMMEDIATE COAST ALL RAIN BY MONDAY AFTERNOON. EXPECT TEMPERATURES TO
REACH INTO THE 30S DUE TO INCREASING SOUTH FLOW AHEAD OF THE
SYSTEM...BUT A STRONG COLD FRONT WILL PUSH THROUGH THE REGION DURING
THE DAY MONDAY USHERING IN MUCH COLDER AIR FOR THE WORK WEEK.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
COLDER AIR WILL FILTER INTO THE REGION FOR MONDAY NIGHT AND
TUESDAY ACCOMPANIED BY MAINLY CLOUDY SKIES ALONG WITH SCATTERED
SNOW SHOWERS AND FLURRIES DUE TO AN UPPER LEVEL TROUGH LINGERING
IN THE REGION. PRECIPITATION WILL BE CONFINED MAINLY TO NORTHERN
AREAS WHERE A FEW HEAVIER SNOW SHOWERS WILL BE POSSIBLE DUE TO
BANDS SETTING UP OFF THE ST. LAWRENCE. HIGH PRESSURE WILL BRIEFLY
MOVE IN FOR WEDNESDAY RESULTING IN MAINLY SUNNY SKIES AND DRY
CONDITIONS REGION WIDE. HOWEVER TEMPERATURES WILL STRUGGLE TO MAKE
IT OUT OF THE LOW TO MID TEENS NORTH WITH HIGHS DOWNEAST REACHING
THE LOW 20S. HIGH PRESSURE WILL SLIDE OFF TO THE EAST THURSDAY AS
THE NEXT UPPER LEVEL TROUGH APPROACHES THE EAST COAST RESULTING IN
INCREASING CLOUDS ALONG WITH THE SLIGHT CHANCE FOR A FEW FLURRIES
FOR THE END OF THE WEEK. AT THIS POINT ANY SURFACE CYCLOGENESIS
ASSOCIATED WITH THIS TROUGH LOOKS TO TAKE PLACE TOO FAR SOUTH AND
EAST TO AFFECT THE REGION WITH SIGNIFICANT PRECIPITATION.
&&
.AVIATION /21Z FRIDAY THROUGH WEDNESDAY/...
NEAR TERM: VFR CONDITIONS TONIGHT WILL LOWER TO IFR IN A WINTRY
MIX ON SATURDAY. THERE MAY BE A BRIEF PERIOD OF MVFR/IFR IN SNOW
AT KBGR AND KBHB BETWEEN 21Z-02Z AS AN AREA OF SNOW SHOWERS MOVES
ACROSS DOWNEAST.
SHORT TERM: IFR CONDITIONS IN SNOW AND RAIN THROUGH THE FIRST
PART OF SATURDAY NIGHT. PERIODS OF FREEZING RAIN WILL BE POSSIBLE
THROUGH 06Z SUNDAY. CONDITIONS WILL GRADUALLY IMPROVE AFTER
MIDNIGHT AND EXPECT ALL TERMINALS TO BE VFR BY 12Z SUNDAY. A
RETURN TO IFR COMES SUNDAY NIGHT AS SNOW SPREADS OVER THE REGION.
IFR IN SNOW AND RAIN SUNDAY NIGHT AND MONDAY.
BRIEF PERIODS OF MVFR/IFR CONDITIONS WILL BE POSSIBLE MONDAY
NIGHT AND TUESDAY FOR THE NORTHERN SITES DUE TO LINGERING SCATTERED SNOW
SHOWERS AND FLURRIES WITH VFR CONDITIONS PREDOMINATING FOR KBGR
AND KBHB. HIGH PRESSURE WILL BUILD IN WEDNESDAY WITH VFR
CONDITIONS EXPECTED FOR ALL SITES.
&&
.MARINE...
NEAR TERM: AS LOW PRESSURE MOVES THROUGH THE GULF OF MAINE, MINIMAL
SCA CONDITIONS POSSIBLE OVER OUR OUTER WATERS ON SATURDAY.
SHORT TERM: NO HEADLINES ANTICIPATED SATURDAY NIGHT AND SUNDAY AS
HIGH PRESSURE BRIEFLY BUILDS OVER THE WATERS. LOW PRESSURE WILL
MOVE BY TO THE NORTH SUNDAY NIGHT AND MONDAY SO EXPECT WINDS AND
SEAS TO INCREASE THROUGH THE PERIOD. A SMALL CRAFT ADVISORY WILL
LIKELY BE NEEDED WITH GALES A POSSIBILITY. WINDS AND SEAS WILL
CONTINUE TO BE AT SCA LEVELS FOR MONDAY NIGHT AND TUESDAY. SEAS
WILL DIMINISH WEDNESDAY BUT WINDS WILL CONTINUE TO REMAIN NEAR SCA
LEVELS BEFORE DIMINISHING FOR WEDNESDAY NIGHT AND THURSDAY.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...WINTER WEATHER ADVISORY FROM 1 AM TO 7 PM EST SATURDAY FOR
MEZ001>006-010.
WINTER WEATHER ADVISORY FROM 1 AM TO NOON EST SATURDAY FOR
MEZ011-015>017-031-032.
MARINE...SMALL CRAFT ADVISORY FROM 6 AM TO 6 PM EST SATURDAY FOR ANZ050-
051.
&&
$$
NEAR TERM...FOSTER
SHORT TERM...HASTINGS
LONG TERM...FITZSIMMONS
AVIATION...FOSTER
MARINE...FOSTER/HASTINGS
AREA FORECAST DISCUSSION
NWS CARIBOU ME
350 PM EST FRI DEC 30 2011
.SYNOPSIS...
LOW PRESSURE OVER THE GREAT LAKES WILL WEAKEN TONIGHT WITH
REDEVELOPMENT OFF OF CAPE COD ON SATURDAY. THIS NEW LOW PRESSURE
WILL TRACK EASTWARD THROUGH THE GULF OF MAINE AND THEN SOUTH OF
NOVA SCOTIA BY SATURDAY EVENING. A HIGH PRESSURE RIDGE WILL BUILD
ACROSS THE REGION ON SUNDAY.
&&
.NEAR TERM /THROUGH SATURDAY/...
SHORTWAVE TROUGH FLATTENING UPPER RIDGE ACROSS THE STATE IS
PRODUCING AN AREA OF LIGHT SNOW SHOWERS ACROSS WESTERN MAINE THIS
AFTERNOON. HRRR MODEL INDICATES AS THIS SHORTWAVE TROUGH MOVES
ACROSS DOWNEAST LATE THIS AFTERNOON INTO THIS EVENING, A PERIOD OF
SNOW SHOWERS CAN BE EXPECTED WITH ANY ACCUMULATION LESS THAN AN
INCH.
MODELS IN GOOD AGREEMENT WITH LOW PRESSURE OVER THE GREAT LAKES
FILLING TONIGHT WITH REDEVELOPMENT JUST EAST OF CAPE COD BY SATURDAY
AFTERNOON. THE LOW PRESSURE WILL THEN TRACK EASTWARD AND MOVE SOUTH
OF NOVA SCOTIA BY SATURDAY NIGHT. AS HAS BEEN THE CASE THIS
WINTER, A LOW PRESSURE TRACKING SOUTH OF THE STATE WILL STILL
ALLOW FOR WARM AIR TO RIDE SOUTHWARD IN ADVANCE OF THE LOW
PRESSURE. THIS WARM AIR ALOFT WILL PRODUCE ANOTHER WINTRY MIX FOR
THE FORECAST AREA. CRITICAL THICKNESS NOW INDICATING MORE MIX THAN
SNOW SO HAVE REDUCE SNOW ACCUMULATION ACROSS CENTRAL AND NORTHERN
SECTIONS BY AROUND AN INCH AND INCREASE ICE ACCUMULATIONS BY A
TENTH OF AN INCH ACROSS CENTRAL PORTIONS. AT THIS TIME, EXPECT THE
AXIS OF HEAVIEST ICE TO OCCUR 30 MILES ON EITHER SIDE OF A LINE
FROM GREENVILLE TO HOULTON WHERE UP TO A QUARTER OF AN INCH MAY
ACCUMULATE. MODELS ALSO INDICATING TEMPERATURES WILL BE SLOW TO
RISE ACROSS DOWNEAST SO WILL EXTEND ADVISORY FROM 7 AM TO NOONTIME
SATURDAY.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/...
THINGS WILL BE WINDING DOWN SATURDAY NIGHT AS THE LOW MOVES OUT OF
THE GULF OF MAINE AND SOUTH OF NOVA SCOTIA. THERE WILL BE SOME
LINGERING FREEZING RAIN IN NORTHERN SECTIONS DURING THE EVENING BUT
COLDER AIR WRAPPING AROUND THE DEPARTING SYSTEM WILL CHANGE THE
PRECIPITATION TO ALL SNOW FROM NORTH TO SOUTH THROUGH THE NIGHT.
SNOWFALL AMOUNTS WILL BE LIGHT...GENERALLY A DUSTING TO AROUND HALF
AN INCH WITH ANOTHER TRACE OF ICE ACCUMULATION.
HIGH PRESSURE WILL BRIEFLY BUILD IN SUNDAY BEFORE ANOTHER LOW
PRESSURE SYSTEM MOVES BY TO OUR NORTH SUNDAY NIGHT AND MONDAY. THIS
WILL BRING ANOTHER ROUND OF SNOW AND RAIN TO THE REGION. THE
RAIN/SNOW LINE WILL BE SOUTH OF HOULTON AND MILLINOCKET WITH THE
IMMEDIATE COAST ALL RAIN BY MONDAY AFTERNOON. EXPECT TEMPERATURES TO
REACH INTO THE 30S DUE TO INCREASING SOUTH FLOW AHEAD OF THE
SYSTEM...BUT A STRONG COLD FRONT WILL PUSH THROUGH THE REGION DURING
THE DAY MONDAY USHERING IN MUCH COLDER AIR FOR THE WORK WEEK.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
COLDER AIR WILL FILTER INTO THE REGION FOR MONDAY NIGHT AND
TUESDAY ACCOMPANIED BY MAINLY CLOUDY SKIES ALONG WITH SCATTERED
SNOW SHOWERS AND FLURRIES DUE TO AN UPPER LEVEL TROUGH LINGERING
IN THE REGION. PRECIPITATION WILL BE CONFINED MAINLY TO NORTHERN
AREAS WHERE A FEW HEAVIER SNOW SHOWERS WILL BE POSSIBLE DUE TO
BANDS SETTING UP OFF THE ST. LAWRENCE. HIGH PRESSURE WILL BRIEFLY
MOVE IN FOR WEDNESDAY RESULTING IN MAINLY SUNNY SKIES AND DRY
CONDITIONS REGION WIDE. HOWEVER TEMPERATURES WILL STRUGGLE TO MAKE
IT OUT OF THE LOW TO MID TEENS NORTH WITH HIGHS DOWNEAST REACHING
THE LOW 20S. HIGH PRESSURE WILL SLIDE OFF TO THE EAST THURSDAY AS
THE NEXT UPPER LEVEL TROUGH APPROACHES THE EAST COAST RESULTING IN
INCREASING CLOUDS ALONG WITH THE SLIGHT CHANCE FOR A FEW FLURRIES
FOR THE END OF THE WEEK. AT THIS POINT ANY SURFACE CYCLOGENESIS
ASSOCIATED WITH THIS TROUGH LOOKS TO TAKE PLACE TOO FAR SOUTH AND
EAST TO AFFECT THE REGION WITH SIGNIFICANT PRECIPITATION.
&&
.AVIATION /20Z FRIDAY THROUGH WEDNESDAY/...
NEAR TERM: VFR CONDITIONS TONIGHT WILL LOWER TO IFR IN A WINTRY
MIX ON SATURDAY. THERE MAY BE A BRIEF PERIOD OF MVFR/IFR IN SNOW
AT KBGR AND KBHB BETWEEN 21Z-02Z AS AN AREA OF SNOW SHOWERS MOVES
ACROSS DOWNEAST.
SHORT TERM: IFR CONDITIONS IN SNOW AND RAIN THROUGH THE FIRST
PART OF SATURDAY NIGHT. PERIODS OF FREEZING RAIN WILL BE POSSIBLE
THROUGH 06Z SUNDAY. CONDITIONS WILL GRADUALLY IMPROVE AFTER
MIDNIGHT AND EXPECT ALL TERMINALS TO BE VFR BY 12Z SUNDAY. A
RETURN TO IFR COMES SUNDAY NIGHT AS SNOW SPREADS OVER THE REGION.
IFR IN SNOW AND RAIN SUNDAY NIGHT AND MONDAY.
BRIEF PERIODS OF MVFR/IFR CONDITIONS WILL BE POSSIBLE MONDAY
NIGHT AND TUESDAY FOR THE NORTHERN SITES DUE TO LINGERING SCATTERED SNOW
SHOWERS AND FLURRIES WITH VFR CONDITIONS PREDOMINATING FOR KBGR
AND KBHB. HIGH PRESSURE WILL BUILD IN WEDNESDAY WITH VFR
CONDITIONS EXPECTED FOR ALL SITES.
&&
.MARINE...
NEAR TERM: AS LOW PRESSURE MOVES THROUGH THE GULF OF MAINE, MINIMAL
SCA CONDITIONS POSSIBLE OVER OUR OUTER WATERS ON SATURDAY.
SHORT TERM: NO HEADLINES ANTICIPATED SATURDAY NIGHT AND SUNDAY AS
HIGH PRESSURE BRIEFLY BUILDS OVER THE WATERS. LOW PRESSURE WILL
MOVE BY TO THE NORTH SUNDAY NIGHT AND MONDAY SO EXPECT WINDS AND
SEAS TO INCREASE THROUGH THE PERIOD. A SMALL CRAFT ADVISORY WILL
LIKELY BE NEEDED WITH GALES A POSSIBILITY. WINDS AND SEAS WILL
CONTINUE TO BE AT SCA LEVELS FOR MONDAY NIGHT AND TUESDAY. SEAS
WILL DIMINISH WEDNESDAY BUT WINDS WILL CONTINUE TO REMAIN NEAR SCA
LEVELS BEFORE DIMINISHING FOR WEDNESDAY NIGHT AND THURSDAY.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...WINTER WEATHER ADVISORY FROM 1 AM TO 7 PM EST SATURDAY FOR
MEZ001>006-010.
WINTER WEATHER ADVISORY FROM 1 AM TO NOON EST SATURDAY FOR
MEZ011-015>017-031-032.
MARINE...SMALL CRAFT ADVISORY FROM 6 AM TO 6 PM EST SATURDAY FOR ANZ050-
051.
&&
$$
NEAR TERM...FOSTER
SHORT TERM...HASTINGS
LONG TERM...FITZSIMMONS
AVIATION...FOSTER
MARINE...FOSTER/HASTINGS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1254 PM EST FRI DEC 30 2011
UPDATED AVIATION DISCUSSION FOR 18Z TAFS
.UPDATE...
NOT A WHOLE LOT OF WEATHER OF SIGNIFICANCE TODAY BUT STILL A TRICKY
UPDATE. CURRENTLY...LOW PRESSURE SYSTEM IS BRINGING MIXED PRECIPITATION
TO SOUTHERN PORTIONS OF WISCONSIN...BUT THIS SYSTEM WILL REMAIN TO
THE SOUTH OF THE CWA THROUGH THE DAY. LOW PRESSURE TROUGH EXTENDS
NORTH OF THE SFC LOW ACROSS CNTRL UPR MI. CONDITIONS ARE MAINLY DRY
THOUGH WITH EVEN SOME SUNSHINE THROUGH HIGHER CLOUDS OVR CNTRL CWA
THIS MORNING. LOW-LEVELS REMAIN VERY SATURATED OVR EASTERN CWA AND
ALONG WITH LOW CLOUDS AND FOG THERE IS LIKELY SOME FZDZ/MIST OCCURRING
AS WELL. LK EFFECT IS RESTRICTED TO CNTRL AND EASTERN LK SUPERIOR
BASED ON VISIBLE SATELLITE.
AS THE LOW TO THE SOUTH HEADS INTO LOWER MICHIGAN LATER TODAY...
EXPECT WINDS OVR MOST OF LK SUPERIOR INTO UPR MI TO BECOME MORE
NORTHERLY. THIS SHOULD ALLOW FOR SOME LK EFFECT SNOW SHOWERS TO WORK
ONSHORE OVR KEWEENAW AND ALSO IN NCNTRL UPR MI. TEMPS AT INVERSION
TOP AROUND 900MB ONLY STRUGGLE TO REACH -7C...SO FZDZ COULD OCCUR.
SEEMS LIKE THERE IS ENOUGH DRY AIR IN BLYR BASED ON SFC DEWPNT
DEPRESSIONS UP TO 4F AT KCMX/KP59 TO LIMIT THAT RISK THOUGH...AND
PROBABLY WOULD JUST SEE FLURRIES IF SNOW SHOWERS CAN NOT REALLY ADVECT
ONSHORE. TEMPS TODAY SHOULD REACH INTO THE 27-32 RANGE...COLDEST IN
THE CNTRL CWA WHERE THE CLEARING LATE LAST NIGHT ALLOWED LOWS TO DIP
TOWARD 10 ABOVE.
ALL LIGHT PRECIPITATION WILL CEASE OVERNIGHT TONIGHT AS WINDS BECOME
MORE SOUTHERLY IN ADVANCE OF STRONGER LOW PRESSURE SYSTEM MOVING
INTO THE PLAINS.
&&
.SYNOPSIS...
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW WNW FLOW ALF OVER
THE GRT LKS BTWN LO AMPLITUDE RDGING OVER THE W AND A TROF N JUST
OFF THE E COAST. SHRTWV RESPONSIBLE FOR SN ON THU IS PUSHING EWD
TOWARD SE ONTARIO...BUT WEAK SFC-H85 TROF REMAINS OVER ERN UPR MI.
BUT WITH DNVA/DEEP LYR QVECTOR DVGC/SUBSIDENCE/DRYING ALF IN THE
WAKE OF THE SHRTWV...THE PCPN OVER THE CWA HAS PRETTY MUCH ENDED.
THE MQT 88D DOES SHOW HIER RADAR RETURNS OVER ECNTRL LK SUP NEAR
WEAK SFC LO CENTER. 00Z INL RAOB SHOWS SHARP INVRN BASE NEAR H875
WITH TEMP JUST BLO THE INVRN DOWN TO -14C...LO ENUF TO SUPPORT LES.
ALTHOUGH THE 00Z INL RAOB INDICATES MODEST DRYING IN THE SUB INVRN
LYR...SKIES ARE GENERALLY CLDY AT MOST LOCATIONS FM THE MN ARROWHEAD
SEWD THRU UPR MI...BUT SOME BREAKS IN THE CLDS ARE EVIDENT. FARTHER
TO THE W/SW IN MN/WI...SKIES ARE MOCLR CLOSER TO WEAK SFC RDG AXIS
ASSOCIATED WITH INCOMING SHRTWV RDG MOVING E THRU MN. ANOTHER PAIR
OF SHRTWVS ARE NOTED IN THE NRN/CNTRL PLAINS...BUT THESE APPEAR TO
BE DIGGING TO THE SE. MUCH FARTHER TO THE W...A STRONG SHRTWV IS
APRCHG THE PAC NW. UPSTREAM HI TEMPS YDAY SUG MAX TEMPS WL GENERALLY
BE ARND 30.
&&
.DISCUSSION...
MAIN FCST CONCERNS THIS PACKAGE SHIFT TO POTENTIAL SN EVENT ON NEW
YEARS DAY/MON RELATED TO SHRTWV NOW APRCHG THE PAC NW.
TDAY...LOOKS LIKE A RELATIVELY QUIET DAY ON TAP WITH WEAK HGT
RISES/DRYING ALF IN THE WAKE OF DEPARTING SHRTWV. SHRTWV COMPLEX IN
THE PLAINS IS FCST TO CONSOLIDATE IN THE LOWER GRT LKS...WITH
ACCOMPANYING DEEP LYR QVECTOR CNVGC/PCPN PASSING S OF UPR MI. FCST
SDNGS SHOW INVRN BASE SINKING TO H9-925 OVER THE CWA IN THE AFTN...
WITH INVRN BASE TEMPS NO LOWER THAN ABOUT -8C. CONSIDERING
THE WEAK SFC WINDS FCST THAT WOULD NOT SUPPORT ORGANIZATION OF LES
BANDS...THE MARGINAL NATURE OF THE CHILL/DGZ ABV THE SUB INVRN
LYR...AND SOME LLVL DRYING...SUSPECT THERE WL BE LTL IN THE WAKE OF
LES. BUT SINCE THE 00Z INL RAOB DID SHOW -14C AIR AT THE H875 INVRN
BASE AND THE GFS/NAM MODEL ANALYSIS WAS ABOUT 3C TOO WARM AT THAT
SITE...WL MAINTAIN GOING POPS NEAR LK SUP...ESPECIALLY E OFMQT WHERE
WEAK SFC TROF IS FCST TO PERSIST THRU THE DAY. ALSO ADDED A MENTION
OF FZDZ IN THIS AREA WHERE THE LLVL MSTR REMAINS A BIT MORE
RESILIENT AND THE LLVL TEMPS ARE NOT LIKELY TO BE AS LO AS OBSVD AT
INL.
TNGT...SHRTWV RDGING WL BE DOMINATING WITH WEAK SFC HI PRES RDG
AXIS BLDG OVHD. MAINTAINED LO CHC POPS IN THE EVNG OVER THE E WHERE
THE SFC LO PRES TROF WL LINGER WHILE SLOWLY WEAKENING WITH TIME.
EXPECT THE LOWEST MIN TEMPS OVER THE INTERIOR SCNTRL WHERE SKIES WL
TREND MOCLR UNDER LIGHT SFC ACYC FLOW.
SAT...AS SHRTWV COMPLEX NOW MOVING TOWARD THE PAC NW SPLITS AND
DEEPENS TROFS IN SCNTRL CAN AND THE CENTRAL PLAINS...INCRSG SW FLOW
WL DVLP OVER THE UPR LKS AND RETURN DEEPER MSTR TO THE UPR LKS. WITH
INITIAL LLVL DRY AIR...RESTRICTED POPS MAINLY ON SAT AFT TO THE NW
HALF OF THE CWA WHERE GUIDANCE SHOWS DEEPER MOISTENING ON CYC SIDE
OF UPR JET AXIS ROTATING NEWD TOWARD THE UPR LKS BY 00Z SUN. SFC
TEMPS ARE PROGGED TO RISE AOA 32 IN THE AFTN AS H85 TEMPS RISE TO
ARND 0C...BUT NAM/SREF FCST WBLB ZERO HGT BLO 500 AGL WITH LINGERING
LLVL DRY AIR SUG VERY LTL CHC RA MAY BE MIXED WITH THE PCPN AT THE
ONSET.
SAT NGT INTO MON...MODELS HAVE BEGUN TO CONVERGE ON A SCENARIO
SHOWING A DEEPENING UPR TROF/SFC LO AS SEPARATE SHRTWVS IN SCNTRL
CAN AND THE CENTRAL PLAINS PHASE. THE GFS IS MOST AGGRESSIVE AT
DEEPENING A CLOSED LO...SHOWING A 984MB SFC LO OVER NRN LK MI BY 12Z
SUN. PER NCEP DISCUSSION...USED A BLEND OF THE INTERMEDIATE STRENGTH
00Z NAM/00Z CNDN/21Z SREF/12Z ECMWF FOR FCST PREPARATION. THESE
MODELS SHOW SFC LO TRACKING ACRS LK SUP/SRN ONTARIO SAT NGT AND
DRAWING ENUF LLVL MSTR OVER UPR MI TO SUPPORT LIKELY POPS UNDER UPR
DVGC ON CYC SIDE OF JET AXIS WHERE 12HR H5 FALLS APRCH 200M. WITH
THE ARRIVAL OF MORE LLVL MSTR OVER THE E...FCST THKNS/WBLB ZERO HGT
SUPPORT AT LEAST A MIX WITH RA IN THAT AREA. ONCE THE LO SHIFTS TO
THE NE LATE SAT NGT/SUN...STRONG NW WINDS WITH H85 WINDS AOA 50KT
ADVECT MUCH COLDER AIR INTO THE UPR LKS...SETTING UP A LK ENHANCED
SN EVENT WITH FCST SDNGS SHOWING DEEP MSTR UNDER LO HGTS AND OMEGA
WITHIN THE LOWERING DGZ AND SHARP CYC FLOW. GUSTY NW WINDS WL ALSO
RESULT IN CONSIDERABLE BLSN. THIS LK ENHANCED SN WL THEN PERSIST
INTO MON BEFORE THE DEEPER MSTR SLOWLY EXITS AND PCPN TENDS TOWARD
PURE LES BY MON NGT. CONSIDERED DOING A WATCH FOR THE NW WIND SN
BELTS...ESPECIALLY OVER THE W WHERE MOST RECENT NCEP GUIDANCE SHOWS
UP TO A FOOT OF SN THRU 12Z MON. BUT SINCE THE BULK OF THE MOST
SGNFT WX WL OCCUR IN THE 5TH TO 7TH PERIODS...OPTED TO ISSUE AN SPS
TO COVER THIS POTENTIAL WINTER STORM.
EXTENDED...LATEST GUIDANCE IN GOOD AGREEMENT SHOWING DEEP UPR TROF
GIVING WAY TO A MORE ZONAL FLOW AFT MID WEEK WITH A WARMING TREND.
DID LOWER FCST MIN TEMPS A FEW DEGREES FM THE ALLBLEND FCST OVER THE
INTERIOR W HALF ON MON NGT GIVEN ARRIVAL OF SFC RDG AXIS/LGT
WINDS/PWAT AS LO AS 0.1 INCH.
&&
.AVIATION /FOR THE 18Z TAF ISSUANCE/...
VARIABLE WINDS OVER THE AREA ARE MAKING FOR A DIFFICULT AVIATION
FCST THIS AFTN. EXPECT MOST SITES TO REMAIN WITH/OR DEVELOP MVFR
CIGS THROUGH THIS EVENING AS WINDS BECOME MORE NORTHERLY OFF LK
SUPERIOR. COULD BE SOME LGT SNOW SHOWERS/FLURRIES LATE THIS AFTN
INTO THE EVENING BUT ANY VSBY REDUCTION WOULD BE BRIEF. ONCE
CLEARING OCCURS LATE TONIGHT...MAY SEE FOG DEVELOP AT KCMX. FAIRLY
QUIET CONDITIONS WILL SETUP ON SATURDAY WITH JUST SOME HIGHER CLOUDS
STREAMING IN FM THE WEST AHEAD OF STRONG SYSTEM THAT IS FORECAST TO
BLAST INTO THE UPPER GREAT LAKES SATURDAY NIGHT.
OUTLOOK...DUE TO STRONG WINDS/HEAVY LK EFFECT SNOW...FLYING
CONDITIONS ARE EXPECTED TO BECOME VERY POOR LATE SATURDAY NIGHT
INTO NEW YEARS DAY. ADVERSE CONDITIONS...POSSIBLY AT OR BLO
AIRPORT MINS...SHOULD CONTINUE INTO MONDAY.
&&
.MARINE /FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE/...
WINDS WILL DIMINISH TODAY AS LOW PRESSURE TROUGH LINGERS OVER LAKE
SUPERIOR. A WEAK RIDGE WILL THEN SLIDE ACROSS LAKE SUPERIOR INTO
SATURDAY BEFORE A STRONG LOW DEVELOPS OVER THE PLAINS AND MOVES
NORTH OF LAKE SUPERIOR FOR NEW YEARS DAY. HIGH END GALES ARE LOOKING
LIKELY FROM THIS SYSTEM...BEGINNING ON NEW YEARS DAY AND CONTINUING
THROUGH MONDAY AS COLDER AIR PLOWS INTO THE GREAT LAKES. HEAVY
FREEZING SPRAY ALSO MAY OCCUR SUNDAY NIGHT INTO MONDAY. GALE AND
HEAVY FREEZING SPRAY WATCHES WILL LIKELY NEED TO BE ISSUED IN THE
NEXT COUPLE DAYS. WINDS DIMINISH SIGNIFICANTLY BY NEXT TUESDAY WITH
ARRIVAL OF HIGH PRESSURE RIDGE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...JLA
SYNOPSIS...KC
DISCUSSION...KC
AVIATION...JLA
MARINE...TITUS
AREA FORECAST DISCUSSION...UPDATED
NWS MARQUETTE MI
1112 AM EST FRI DEC 30 2011
.UPDATE...
NOT A WHOLE LOT OF WEATHER OF SIGNIFICANCE TODAY BUT STILL A TRICKY
UPDATE. CURRENTLY...LOW PRESSURE SYSTEM IS BRINGING MIXED PRECIPITATION
TO SOUTHERN PORTIONS OF WISCONSIN...BUT THIS SYSTEM WILL REMAIN TO
THE SOUTH OF THE CWA THROUGH THE DAY. LOW PRESSURE TROUGH EXTENDS
NORTH OF THE SFC LOW ACROSS CNTRL UPR MI. CONDITIONS ARE MAINLY DRY
THOUGH WITH EVEN SOME SUNSHINE THROUGH HIGHER CLOUDS OVR CNTRL CWA
THIS MORNING. LOW-LEVELS REMAIN VERY SATURATED OVR EASTERN CWA AND
ALONG WITH LOW CLOUDS AND FOG THERE IS LIKELY SOME FZDZ/MIST OCCURRING
AS WELL. LK EFFECT IS RESTRICTED TO CNTRL AND EASTERN LK SUPERIOR
BASED ON VISIBLE SATELLITE.
AS THE LOW TO THE SOUTH HEADS INTO LOWER MICHIGAN LATER TODAY...
EXPECT WINDS OVR MOST OF LK SUPERIOR INTO UPR MI TO BECOME MORE
NORTHERLY. THIS SHOULD ALLOW FOR SOME LK EFFECT SNOW SHOWERS TO WORK
ONSHORE OVR KEWEENAW AND ALSO IN NCNTRL UPR MI. TEMPS AT INVERSION
TOP AROUND 900MB ONLY STRUGGLE TO REACH -7C...SO FZDZ COULD OCCUR.
SEEMS LIKE THERE IS ENOUGH DRY AIR IN BLYR BASED ON SFC DEWPNT
DEPRESSIONS UP TO 4F AT KCMX/KP59 TO LIMIT THAT RISK THOUGH...AND
PROBABLY WOULD JUST SEE FLURRIES IF SNOW SHOWERS CAN NOT REALLY ADVECT
ONSHORE. TEMPS TODAY SHOULD REACH INTO THE 27-32 RANGE...COLDEST IN
THE CNTRL CWA WHERE THE CLEARING LATE LAST NIGHT ALLOWED LOWS TO DIP
TOWARD 10 ABOVE.
ALL LIGHT PRECIPITATION WILL CEASE OVERNIGHT TONIGHT AS WINDS BECOME
MORE SOUTHERLY IN ADVANCE OF STRONGER LOW PRESSURE SYSTEM MOVING
INTO THE PLAINS.
&&
PREV DISCUSSION...ISSUED AT 636 AM EST FRI DEC 30 2011...
.SYNOPSIS...
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW WNW FLOW ALF OVER
THE GRT LKS BTWN LO AMPLITUDE RDGING OVER THE W AND A TROF N JUST
OFF THE E COAST. SHRTWV RESPONSIBLE FOR SN ON THU IS PUSHING EWD
TOWARD SE ONTARIO...BUT WEAK SFC-H85 TROF REMAINS OVER ERN UPR MI.
BUT WITH DNVA/DEEP LYR QVECTOR DVGC/SUBSIDENCE/DRYING ALF IN THE
WAKE OF THE SHRTWV...THE PCPN OVER THE CWA HAS PRETTY MUCH ENDED.
THE MQT 88D DOES SHOW HIER RADAR RETURNS OVER ECNTRL LK SUP NEAR
WEAK SFC LO CENTER. 00Z INL RAOB SHOWS SHARP INVRN BASE NEAR H875
WITH TEMP JUST BLO THE INVRN DOWN TO -14C...LO ENUF TO SUPPORT LES.
ALTHOUGH THE 00Z INL RAOB INDICATES MODEST DRYING IN THE SUB INVRN
LYR...SKIES ARE GENERALLY CLDY AT MOST LOCATIONS FM THE MN ARROWHEAD
SEWD THRU UPR MI...BUT SOME BREAKS IN THE CLDS ARE EVIDENT. FARTHER
TO THE W/SW IN MN/WI...SKIES ARE MOCLR CLOSER TO WEAK SFC RDG AXIS
ASSOCIATED WITH INCOMING SHRTWV RDG MOVING E THRU MN. ANOTHER PAIR
OF SHRTWVS ARE NOTED IN THE NRN/CNTRL PLAINS...BUT THESE APPEAR TO
BE DIGGING TO THE SE. MUCH FARTHER TO THE W...A STRONG SHRTWV IS
APRCHG THE PAC NW. UPSTREAM HI TEMPS YDAY SUG MAX TEMPS WL GENERALLY
BE ARND 30.
&&
.DISCUSSION...
MAIN FCST CONCERNS THIS PACKAGE SHIFT TO POTENTIAL SN EVENT ON NEW
YEARS DAY/MON RELATED TO SHRTWV NOW APRCHG THE PAC NW.
TDAY...LOOKS LIKE A RELATIVELY QUIET DAY ON TAP WITH WEAK HGT
RISES/DRYING ALF IN THE WAKE OF DEPARTING SHRTWV. SHRTWV COMPLEX IN
THE PLAINS IS FCST TO CONSOLIDATE IN THE LOWER GRT LKS...WITH
ACCOMPANYING DEEP LYR QVECTOR CNVGC/PCPN PASSING S OF UPR MI. FCST
SDNGS SHOW INVRN BASE SINKING TO H9-925 OVER THE CWA IN THE AFTN...
WITH INVRN BASE TEMPS NO LOWER THAN ABOUT -8C. CONSIDERING
THE WEAK SFC WINDS FCST THAT WOULD NOT SUPPORT ORGANIZATION OF LES
BANDS...THE MARGINAL NATURE OF THE CHILL/DGZ ABV THE SUB INVRN
LYR...AND SOME LLVL DRYING...SUSPECT THERE WL BE LTL IN THE WAKE OF
LES. BUT SINCE THE 00Z INL RAOB DID SHOW -14C AIR AT THE H875 INVRN
BASE AND THE GFS/NAM MODEL ANALYSIS WAS ABOUT 3C TOO WARM AT THAT
SITE...WL MAINTAIN GOING POPS NEAR LK SUP...ESPECIALLY E OFMQT WHERE
WEAK SFC TROF IS FCST TO PERSIST THRU THE DAY. ALSO ADDED A MENTION
OF FZDZ IN THIS AREA WHERE THE LLVL MSTR REMAINS A BIT MORE
RESILIENT AND THE LLVL TEMPS ARE NOT LIKELY TO BE AS LO AS OBSVD AT
INL.
TNGT...SHRTWV RDGING WL BE DOMINATING WITH WEAK SFC HI PRES RDG
AXIS BLDG OVHD. MAINTAINED LO CHC POPS IN THE EVNG OVER THE E WHERE
THE SFC LO PRES TROF WL LINGER WHILE SLOWLY WEAKENING WITH TIME.
EXPECT THE LOWEST MIN TEMPS OVER THE INTERIOR SCNTRL WHERE SKIES WL
TREND MOCLR UNDER LIGHT SFC ACYC FLOW.
SAT...AS SHRTWV COMPLEX NOW MOVING TOWARD THE PAC NW SPLITS AND
DEEPENS TROFS IN SCNTRL CAN AND THE CENTRAL PLAINS...INCRSG SW FLOW
WL DVLP OVER THE UPR LKS AND RETURN DEEPER MSTR TO THE UPR LKS. WITH
INITIAL LLVL DRY AIR...RESTRICTED POPS MAINLY ON SAT AFT TO THE NW
HALF OF THE CWA WHERE GUIDANCE SHOWS DEEPER MOISTENING ON CYC SIDE
OF UPR JET AXIS ROTATING NEWD TOWARD THE UPR LKS BY 00Z SUN. SFC
TEMPS ARE PROGGED TO RISE AOA 32 IN THE AFTN AS H85 TEMPS RISE TO
ARND 0C...BUT NAM/SREF FCST WBLB ZERO HGT BLO 500 AGL WITH LINGERING
LLVL DRY AIR SUG VERY LTL CHC RA MAY BE MIXED WITH THE PCPN AT THE
ONSET.
SAT NGT INTO MON...MODELS HAVE BEGUN TO CONVERGE ON A SCENARIO
SHOWING A DEEPENING UPR TROF/SFC LO AS SEPARATE SHRTWVS IN SCNTRL
CAN AND THE CENTRAL PLAINS PHASE. THE GFS IS MOST AGGRESSIVE AT
DEEPENING A CLOSED LO...SHOWING A 984MB SFC LO OVER NRN LK MI BY 12Z
SUN. PER NCEP DISCUSSION...USED A BLEND OF THE INTERMEDIATE STRENGTH
00Z NAM/00Z CNDN/21Z SREF/12Z ECMWF FOR FCST PREPARATION. THESE
MODELS SHOW SFC LO TRACKING ACRS LK SUP/SRN ONTARIO SAT NGT AND
DRAWING ENUF LLVL MSTR OVER UPR MI TO SUPPORT LIKELY POPS UNDER UPR
DVGC ON CYC SIDE OF JET AXIS WHERE 12HR H5 FALLS APRCH 200M. WITH
THE ARRIVAL OF MORE LLVL MSTR OVER THE E...FCST THKNS/WBLB ZERO HGT
SUPPORT AT LEAST A MIX WITH RA IN THAT AREA. ONCE THE LO SHIFTS TO
THE NE LATE SAT NGT/SUN...STRONG NW WINDS WITH H85 WINDS AOA 50KT
ADVECT MUCH COLDER AIR INTO THE UPR LKS...SETTING UP A LK ENHANCED
SN EVENT WITH FCST SDNGS SHOWING DEEP MSTR UNDER LO HGTS AND OMEGA
WITHIN THE LOWERING DGZ AND SHARP CYC FLOW. GUSTY NW WINDS WL ALSO
RESULT IN CONSIDERABLE BLSN. THIS LK ENHANCED SN WL THEN PERSIST
INTO MON BEFORE THE DEEPER MSTR SLOWLY EXITS AND PCPN TENDS TOWARD
PURE LES BY MON NGT. CONSIDERED DOING A WATCH FOR THE NW WIND SN
BELTS...ESPECIALLY OVER THE W WHERE MOST RECENT NCEP GUIDANCE SHOWS
UP TO A FOOT OF SN THRU 12Z MON. BUT SINCE THE BULK OF THE MOST
SGNFT WX WL OCCUR IN THE 5TH TO 7TH PERIODS...OPTED TO ISSUE AN SPS
TO COVER THIS POTENTIAL WINTER STORM.
EXTENDED...LATEST GUIDANCE IN GOOD AGREEMENT SHOWING DEEP UPR TROF
GIVING WAY TO A MORE ZONAL FLOW AFT MID WEEK WITH A WARMING TREND.
DID LOWER FCST MIN TEMPS A FEW DEGREES FM THE ALLBLEND FCST OVER THE
INTERIOR W HALF ON MON NGT GIVEN ARRIVAL OF SFC RDG AXIS/LGT
WINDS/PWAT AS LO AS 0.1 INCH.
&&
.AVIATION /FOR THE 12Z TAF ISSUANCE/...
LIGHT LOW-LEVEL WIND REGIME THRU THIS FCST PERIOD SUGGESTS
CONDITIONS PROBABLY WILL NOT CHANGE MUCH AT KIWD/KCMX/KSAW.
SO...GIVEN THE LOW-LEVEL MOISTURE OVER THE AREA AND GENERAL MVFR
CIGS...MVFR CIGS WILL LIKELY PREVAIL THRU THE FCST PERIOD.
HOWEVER...THERE MAY BE SOME PERIODS WHERE CLOUDS SCATTER OUT OR CIGS
RISE TO VFR AS INDICATED BY CURRENT REGIONAL SFC OBS AND SATELLITE
IMAGERY.
FG AS SAW SHOULD BURN OFF THIS MORNING AS SURFACE TEMPS INCREASE.
FG MAY FORM AT CMX TONIGHT GIVEN ABUNDANT LOW LEVEL MOISTURE...IF
CLOUDS CAN CLEAR OUT ENOUGH. THE EXACT TIMING IS STILL IN QUESTION.
&&
.MARINE /FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE/...
WINDS WILL DIMINISH TODAY AS LOW PRESSURE TROUGH LINGERS OVER LAKE
SUPERIOR. A WEAK RIDGE WILL THEN SLIDE ACROSS LAKE SUPERIOR INTO
SATURDAY BEFORE A STRONG LOW DEVELOPS OVER THE PLAINS AND MOVES
NORTH OF LAKE SUPERIOR FOR NEW YEARS DAY. HIGH END GALES ARE LOOKING
LIKELY FROM THIS SYSTEM...BEGINNING ON NEW YEARS DAY AND CONTINUING
THROUGH MONDAY AS COLDER AIR PLOWS INTO THE GREAT LAKES. HEAVY
FREEZING SPRAY ALSO MAY OCCUR SUNDAY NIGHT INTO MONDAY. GALE AND
HEAVY FREEZING SPRAY WATCHES WILL LIKELY NEED TO BE ISSUED IN THE
NEXT COUPLE DAYS. WINDS DIMINISH SIGNIFICANTLY BY NEXT TUESDAY WITH
ARRIVAL OF HIGH PRESSURE RIDGE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...JLA
SYNOPSIS...KC
DISCUSSION...KC
AVIATION...TITUS
MARINE...TITUS
AREA FORECAST DISCUSSION...UPDATED
NWS GLASGOW MT
930 AM MST FRI DEC 30 2011
.SHORT TERM...FOR NORTHEAST MONTANA...TODAY THROUGH SUNDAY...
SENT AN UPDATE THIS MORNING TO ADJUST...ADD...AND FINE TUNE THE
PLACEMENT AND TIMING OF SPRINKLES AND LIGHT RAIN ACCORDING TO
CURRENT RADAR TRENDS AND HRRR MODEL DEPICTIONS LEADING INTO THE
TONIGHT TIME FRAME. IT LOOKS LIKE THERE COULD BE SOME SCATTERED
SPRINKLES AS THE SYSTEM GET ORGANIZED AHEAD OF THE LINEAR
PRECIPITATION FEATURE TONIGHT. ALSO LOWERED TEMPERATURES JUST A
BIT DUE TO MORE EXPECTED CLOUD COVER. BMICKELSON
PREVIOUS SHORT TERM DISCUSSION...WINDS HAVE FINALLY DIMINISHED TO
10 KNOTS OR LESS ACROSS NORTHEAST MONTANA AT 10Z. THE LIGHT WINDS
WILL BE SHORT LIVED AS THE NEXT COLD FRONT MOVES THROUGH TONIGHT
WITH A CHANCE OF RAIN OR SNOW. THE FRONT WILL BE FOLLOWED BY
STRONG WEST TO NORTHWEST WINDS ON SATURDAY. HAVE ISSUED A HIGH
WIND WATCH FOR THE ENTIRE FORECAST AREA FOR SATURDAY AND SATURDAY
EVENING.
SHORTWAVE RIDGE WILL BRING MILD WEATHER TO THE AREA TODAY BUT IT
WILL NOT BE AS WARM AS IT WAS YESTERDAY. CLOUDS WILL INCREASE
AHEAD OF A COLD FRONT THAT WILL MOVE THROUGH EASTERN MONTANA
TONIGHT. DEEPER MOISTURE MOVES INTO THE AREA THIS EVENING ON
SOUTHWEST FLOW ALOFT. THIS WILL BRING A CHANCE OF RAIN STARTING
THIS EVENING WITH THE BEST CHANCE OF RAIN SOUTH OF THE MISSOURI
RIVER. AS TEMPERATURES COOL ALOFT TONIGHT...RAIN MAY MIX WITH SNOW
BEFORE IT MOVES TO THE EAST SATURDAY MORNING.
UPPER TROUGH MOVES THROUGH THE AREA ON SATURDAY WITH DECENT COLD
AIR ADVECTION. 850 MB WINDS INCREASE TO AROUND 50 KNOTS (GFS
SOMEWHAT STRONGER, ECMWF SOMEWHAT WEAKER) SATURDAY MORNING AND
REMAIN THERE INTO SATURDAY EVENING. WITH GOOD MIXING AND MOMENTUM
TRANSFER EXPECTED ALONG WITH OVER 20 MB PRESSURE RISE...WINDS HAVE A
GOOD CHANCE OF REACHING WARNING CRITERIA OF 40 MPH SUSTAINED WITH
GUSTS TO 58 MPH. THE STRONGEST WINDS WILL BE IN THE EAST BUT NOT
READY TO RULE OUT THE WEST REACHING HIGH WIND CRITERIA. WILL
INCLUDE THE ENTIRE FORECAST AREA IN THE HIGH WIND WATCH FOR
SATURDAY AND SATURDAY EVENING. COLD AIR ADVECTION WILL LIMIT
TEMPERATURE RISES ON SATURDAY AND THE NORTHERN ZONES MAY SEE A FEW
FLAKES OF WRAP AROUND SNOW FROM AN UPPER LOW MOVING THROUGH SASKATCHEWAN.
HIGH PRESSURE WILL MOVE INTO THE AREA SATURDAY NIGHT. SKIES WILL
GRADUALLY CLEAR AND WINDS WILL SLOWLY DIMINISH. TEMPERATURES WILL
BE COLDER THAN THEY HAVE BEEN FOR SEVERAL DAYS. THE COLD AIR WILL
LINGER INTO SUNDAY WHILE THE NEXT RIDGE BUILDS IN FROM THE WEST. FORRESTER
.LONG TERM...SUNDAY NIGHT THROUGH FRIDAY...
THE EXTENDED PERIOD BEGINS WITH AN UPPER LEVEL RIDGE AXIS OVER THE
ROCKY MOUNTAINS AND NORTHWESTERLY FLOW ALOFT OVER EASTERN MONTANA.
THE APPROACHING RIDGE SENDS A WARM FRONT INTO THE FORECAST AREA
SUNDAY NIGHT AND MONDAY. THIS WILL ONCE AGAIN RAMP TEMPERATURES
ABOVE NORMAL ON MONDAY.
MONDAY NIGHT...THE GFS...AND TO A LESSER EXTENT THE EC...PICK UP A
DRY SHORTWAVE TROUGH THAT WILL KNOCK DOWN THE RIDGE AND RAMP UP
WINDS A BIT THROUGH TUESDAY MORNING.
TUESDAY...THE RIDGE RE-ESTABLISHES ITSELF WITH TEMPERATURES
TRENDING WELL ABOVE NORMAL...WITH POSSIBLY RECORD HIGHS. THIS
RIDGE WILL MAINTAIN RELATIVELY WARM AND DRY CONDITIONS THROUGH
THURSDAY.
THURSDAY NIGHT AND FRIDAY...AN EASTERN PACIFIC UPPER TROUGH AND
STORM SYSTEM SLAMS INTO THE WEST COAST WEDNESDAY NIGHT...THEN
SWINGS EAST ACROSS THE DIVIDE BY FRIDAY. 850MB TEMPERATURES
QUICKLY FALL TO AROUND -10*C. WITH PRECIPITATION A POSSIBILITY
THERE SHOULD BE A TRANSITION FROM RAIN TO SNOW WITH THIS WAVE.
THIS WILL BECOME A WINTER STORM OVER WESTERN AND CENTRAL
MONTANA...SOME OF WHICH MAY AFFECT OUR WESTERN ZONES FOR A SHORT
PERIOD. THIS WAVE WILL ALSO TREND TEMPERATURE DOWN TOWARDS NORMAL.
SCT
&&
.AVIATION...
VFR TODAY. A SHORT PERIOD UPPER RIDGE WILL BE INTERRUPTED BY A
SHORTWAVE TROUGH THIS AFTERNOON WHICH COULD INTRODUCE RAIN AND
SNOW SHOWERS THIS EVENING...AFFECTING MAINLY KGDV AND KSDY. THIS
COULD PRODUCE MVFR CEILINGS. EXPECT NW WINDS TO BECOME SOUTHERLY
THIS AFTERNOON...THEN SOUTHWESTERLY THIS EVENING...ALL AROUND
5-10KTS. SCT
&&
.GLASGOW WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WATCH FROM SATURDAY MORNING THROUGH SATURDAY EVENING
FOR CENTRAL AND SOUTHEAST PHILLIPS...CENTRAL AND SOUTHERN
VALLEY...DANIELS...SHERIDAN...WESTERN ROOSEVELT...PETROLEUM...
GARFIELD...MCCONE...RICHLAND...DAWSON...PRAIRIE...WIBAUX...
NORTHERN PHILLIPS...SOUTHWEST PHILLIPS...NORTHERN VALLEY...
EASTERN ROOSEVELT.
&&
$$
WEATHER.GOV/GLASGOW