Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 02/24/14
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
859 PM EST SUN FEB 23 2014
.SYNOPSIS...
A COLD FRONT WILL MOVE OFF THE MID ATLANTIC COAST TONIGHT. BEHIND
THE FRONT, HIGH PRESSURE WILL BUILD IN FOR MONDAY INTO TUESDAY.
THEN, AN AREA OF LOW PRESSURE IS ANTICIPATED TO DEVELOP ALONG THE
CAROLINA COAST ON TUESDAY NIGHT BEFORE MOVING OUT TO SEA ON
WEDNESDAY MORNING. THE LOW SHOULD PASS WELL TO OUR SOUTHEAST AND
EAST ON WEDNESDAY. HIGH PRESSURE IS FORECAST FOR WEDNESDAY NIGHT
AND THURSDAY. ANOTHER COLD FRONT WILL PASS THROUGH THE REGION ON
THURSDAY NIGHT FOLLOWED BY ANOTHER AREA OF HIGH PRESSURE FOR
FRIDAY. MORE LOW PRESSURE MAY AFFECT THE REGION ON SATURDAY.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
WITH THE EVENING UPDATE, WE INCREASED POPS FOR A FEW HOURS INTO
THE LIKELY RANGE, MAINLY ACROSS PORTIONS OF SOUTHEAST PA AND INTO
FAR NORTHERN MD/DE BASED ON CURRENT RADAR TRENDS AND LATEST MODEL
OUTPUT FROM THE HRRR AND RAP. STILL EXPECTING THE PRECIP TO BE
MAINLY LIGHT RAIN AS IT PROGRESSES FROM WEST TO EAST ACROSS THE
AREA, WITH PERHAPS SOME LIGHT SNOW MIXING IN AS ITS ENDING WITH
COLDER AIR FILTERING IN. A FEW ADJUSTMENTS WERE MADE TO HOURLY
TEMPS AND DEWPOINTS AS WELL USING LAV/LAMP GUIDANCE.
OTHERWISE, A COLD FRONT WILL CONTINUE TO PROGRESS SOUTH AND EAST
OF OUR AREA AND OFF THE COAST. A WEAK WAVE OF LOW PRESSURE IS
DEVELOPING ALONG THE FRONT LATE THIS EVENING, AND IT WILL QUICKLY
MOVE OFFSHORE OVERNIGHT. INCREASING CLOUDS AND SOME LIGHT SHOWERS
(MOSTLY RAIN) WILL ACCOMPANY THE WAVE. POPS ARE MOSTLY IN THE
LIKELY TO HIGH CHC RANGE FROM WEST TO EAST ACROSS THE FCST AREA.
QPF AMOUNTS RANGE FROM A TRACE TO A FEW HUNDREDTHS FOR OUR REGION.
IT IS POSSIBLE THAT SOME COLDER AIR MAY ARRIVE BEFORE THE PRECIP
ENDS, AND A BIT OF LIGHT SNOW IS POSSIBLE. WE HAVE TRIMMED ANY
ACCUMS TO LESS THAN AN INCH. LOW TEMPERATURES TONIGHT (WHICH WILL
OCCUR LATE) WILL BE IN THE MID/UPPER 20S FAR NORTH AND LOW 30S
OVER THE DELMARVA AND DEL VALLEY LOCATIONS. WINDS WILL MOSTLY BE
WEST OR NORTHWEST AT 5 TO 10 MPH.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/...
HIGH PRESSURE WELL TO THE WEST WILL BEGIN TO BUILD ACROSS OUR REGION
MONDAY. FAIR WEATHER IS EXPECTED, BUT GUSTY WINDS AND COLD
TEMPERATURES WILL BRING THAT WINTRY FEEL BACK TO THE AREA. HIGH
TEMPERATURES WILL BE IN THE 20S FAR NORTH AND UPPER 30S/LOW 40S
SOUTH. WINDS WILL BE 10 TO 20 MPH WITH GUSTS TO 30 MPH DURING THE
AFTERNOON.
&&
.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
COLD HIGH PRES WILL BE OVER THE REGION AT THE START OF THE PD. IT
WILL MOVE EWD ON TUE AS A REINFORCING SHOT BUILDS DOWN FROM
CANADA. A WK DISTURBANCE IN THE FLOW COULD TRIGGER SOME SNOW
SHOWERS, MAINLY S ON TUE, HOWEVER NOT ALL OF THE GUID IS IN
AGREEMENT WITH THIS. THEN, TWO FEATURES WILL APPROACH THE REGION
TUE NIGHT INTO WED. THE FIRST IS A WK CDFNT FROM THE NW. THE
SECOND, AND MORE IMPORTANT IS AN AREA OF LOW PRES WHICH WILL TAKE
SHAPE ACRS THE GLFMEX TUE NIGHT AND MOVE TO THE CAROLINA CST BY
WED MRNG. FROM THERE IT CONTINUES ITS NEWD TRACK OUT TO SEA.
FOR THE PAST SEVERAL DAYS, ALL OF THE MDLS, EXCEPT FOR THE ECMWF
HAD A FAIRLY E TRACK WHICH WOULD HAVE ONLY BROUGHT US SOME LIGHT
SNOW ACCUMULATIONS. THE ECMWF HAD A MORE W TRACK AND INDICATED
MORE IMPACTS. WITH THE MORE WWD TRACKS WINNING OUT THIS WINTER AND
THE ECMWF`S GENERAL TRACK RECORD AND CERTAINLY OF LATE, ITS SOLN
COULD NOT BE IGNORED.
HOWEVER, OVER THE PAST 2 MDL CYCLES, IT HAS TRENDED EWD AND IT IS
IN MUCH BETTER AGREEMENT WITH THE MDL CONSENSUS, THOUGH MARGINALLY
STILL FURTHER W. BASED ON THE CURRENT TRACK, WE WOULD BE LOOKING
AT A LOW END ADVISORY SNOW. NEVERTHELESS, THIS HAS BEEN THE WINTER
FOR STORMS TO RAMP UP IN THE FINAL DAY OR TWO, SO WE`LL HAVE TO
SEE IF THAT OCCURS, BUT FOR RIGHT NOW BASED ON CURRENT TRACK AND TIMING,
THIS APPEARS TO BE A MINOR NUISANCE, EVEN THOUGH BASED ON TIMING
IT WOULD HAVE IMPACTS ON THE WED MRNG RUSH HOUR. IT SHOULD BE OVER
WITH BY WED PM RUSH HOUR.
ANOTHER COLD AREA OF HIGH PRES BUILD IN BEHIND THE DEPARTING LOW.
WED INTO THU LOOKS TO BE A BIT BREEZY DUE TO THE PGRAD BETWEEN THE
AFOREMENTIONED HIGH AND THE DEPARTING LOW. ANOTHER CDFNT SHOULD
CROSS THE AREA THU NIGHT AND LOOKS TO BE DRY. THE DRY WX WILL
CONTINUE INTO FRI.
THEN ALL OF THE GUID WANTS TO DEVELOP ANOTHER AREA OF LOW PRES
ALONG THE SRN FLANK OF YET ANOTHER LARGE HIGH DROPPING DOWN FROM
CANADA...SOMEWHERE ACRS THE GLFMEX OR SERN STATES. WHERE IS GOES
FROM THERE AND HOW MUCH WE WARM UP IN ADVANCE OF THIS LOW WILL
DETERMINE PRECIP TYPE. FOR NOW WILL JUST CARRY LOW POPS AND SNOW.
TEMPS LOOK TO BE MUCH BELOW NRML THRU THE PD. MEX TEMPS WHICH ARE
TRENDING TWD CLIMO AT THE END OF THE PD SEEM WAY TOO WARM, WITH
THESE CONTINUED CANADIAN HIGHS MOVG DOWN.
&&
.AVIATION /02Z MONDAY THROUGH FRIDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
MAINLY VFR CONDITIONS ARE EXPECTED THROUGH THE TAF PERIOD. WEST-
NORTHWESTERLY WINDS WILL CONTINUE THROUGH THE OVERNIGHT, WITH
SPEEDS MAINLY IN THE 6 TO 10 KT RANGE. A WEAK WAVE OF LOW PRESSURE WILL
DEVELOP TO OUR SW ALONG A FRONTAL BOUNDARY AND QUICKLY MOVE OFF THE
COAST. CEILINGS WILL LOWER SOME AND A FEW SCATTERED RAIN SHOWERS
WILL ACCOMPANY THE WAVE. OVERALL WITH THE 0Z TAFS, WE STILL EXPECT
CONDITIONS TO STAY MAINLY VFR THROUGH THE 02Z TO 06Z TIMEFRAME AS
THE SHOWERS PASS BY, BUT A BRIEF LOWERING TO MVFR IS POSSIBLE,
ESPECIALLY FOR KRDG AND KABE. AT MOST OF THE TAF SITES, THE PRECIP
SHOULD END BEFORE ANY MIXING WITH SNOW OCCURS.
INTO MONDAY...VFR CONDITIONS AS CLOUDS SCATTER OUT. MAINLY CLEAR
SKIES LATER IN THE DAYTIME WITH AN INCREASING AND GUSTY W/NW WIND
EXPECTED. GUSTS 20-30 KNOTS ARE EXPECTED DURING THE LATE MORNING
TO EARLY EVENING.
OUTLOOK...
MON NIGHT AND TUE...MAINLY VFR. HIGH CONFIDENCE
TUE NIGHT AND WED...A LOW PRES SYS IS FCST TO MOVE FROM THE
CAROLINA CST NEWD OFFSHORE. THERE IS THE POTENTIAL FOR CONDITIONS
TO LOWER INTO THE IFR RANGE IN SNOW. A GUSTY NORTHEAST WIND IS
POSSIBLE ON TUESDAY NIGHT MAINLY FROM KPHL EAST AND SOUTHWARD. A
GUSTY NORTH TO NORTHWEST WIND MAY DEVELOP AT ALL LOCATIONS FOR
WEDNESDAY. LOW TO MDT CONFIDENCE DEPENDING ON TRACK.
WED NIGHT AND THU...VFR. HIGH CONFIDENCE.
&&
.MARINE...
A WEAK COLD FRONT WILL CROSS THE WATERS OVER THE NEXT FEW HOURS.
WINDS WILL SWITCH TO NW BEHIND THE FRONT. THE COOLER AIR WILL ARRIVE
TONIGHT AND BETTER MIXING WILL CREATE GUSTY WINDS OVERNIGHT. THE
PRESENT TIMING FOR THE BEGINNING OF THE SCA FLAG LOOKS GOOD, SO WE
WILL NOT MAKE ANY CHANGES ATTM. WINDS WILL REMAIN GUSTY THRU TUE
MORNING. SCT SHOWERS WILL BE ACROSS THE WATERS EARLY TONIGHT, THEN
DRY WEATHER LATER TONIGHT AND MONDAY.
OUTLOOK...
MON NIGHT...SCA FLAGS ALREADY FLYING. ISOLATED GALE GUSTS PSBL.
TUE INTO TUE NIGHT....NO MARINE HEADLINES ARE ANTICIPATED.
WED...SCA CONDS ARE LIKELY AND GALES PSBL DUE TO CSTL LOW MOVG
FROM THE CAROLINA CST WELL OFFSHORE.
WED NIGHT AND THU...SCA CONDS PSBL DUE TO A GUSTY W WIND. WIND
SPEEDS SUBSIDE ON THU AFTN. FREEZING SPRAY MAY BEGIN TO BECOME A
CONCERN AS VERY COLD AIR BUILDS ACROSS THE COASTAL WATERS OF NEW
JERSEY AND DELAWARE.
&&
.CLIMATE...
A LITTLE LATE BUT WE HAVE LOOKED AT CONSECUTIVE DAYS OF 1 INCH OR
GREATER SNOW DEPTH ON THE GROUND AT 7 AM... AND FOUND THE FOLLOWING.
ALLENTOWN THROUGH TODAY-FEBRUARY 23, HAS RECORDED 33 CONSECUTIVE
DAYS OF 1 INCH OR GREATER SNOW DEPTH WHICH PLACES THIS AS THE 11TH
LONGEST IN OFFICIAL RECORDS DATING BACK TO 1923. THE STREAK FOR
ALLENTOWN BEGAN JANUARY 22.
SINCE THIS EVENING THERE STILL WAS A SNOW DEPTH OF 8 INCHES ON
THE GROUND PACKED WITH A LITTLE OVER 3 INCHES OF WATER EQUIVALENCE...
AND TEMPERATURES FOR THE PERIOD MONDAY THROUGH NEXT SUNDAY...SHOULD
NOT EXCEED 34 DEGREES... ODDS FAVOR THIS STRETCH OF CONTINUAL
SNOWCOVER PROBABLY APPROACHING OR POSSIBLY EXCEEDING 40 DAYS.
THIS...EVEN IF WE WERE TO PROCEED WITHOUT ANY RENEWED SNOW
ACCUMULATION BEFORE NEXT SUNDAY.
RANKING BELOW LONGEST
1. 78 DAYS ENDING 3/22/1994
2. 59 DAYS ENDING 3/13/1978
3 TIED. 49 DAYS ENDING 2/12/1977 AND 49 DAYS ENDING 2/19/1925
4. 45 DAYS ENDING 3/4/1936
5. 43 DAYS ENDING 2/2/1970
6. 42 DAYS ENDING 3/6/1963
7. 41 DAYS ENDING 1/19/1996
8. 37 DAYS ENDING 2/17/1948
9. 36 DAYS ENDING 2/11/2011
10. 34 DAYS ENDING 2/22/1961
11. 33 DAYS ENDING 2/23/2014
PHILADELPHIA...NO LONGER WITH ANY SNOW ON THE GROUND...RECORDED
18 CONSECUTIVE DAYS BEFORE NO SNOW WAS RECORDED ON THE GROUND ON
FEBRUARY 22ND. THE STREAK BEGAN ON THE 4TH OF FEBRUARY. THAT WAS
THE 7TH LONGEST PERIOD OF CONTINUAL SNOWCOVER WITH RECORDS
SEARCHED DATING BACK TO ONLY 1948....A SHORTER PERIOD OF RECORD.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 4 AM MONDAY TO 6 AM EST TUESDAY FOR
ANZ430-431-450>455.
&&
$$
SYNOPSIS...KLINE/NIERENBERG
NEAR TERM...KLINE/O`HARA
SHORT TERM...O`HARA
LONG TERM...NIERENBERG
AVIATION...KLINE/NIERENBERG/O`HARA
MARINE...NIERENBERG/O`HARA
CLIMATE...GAINES/DRAG
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
348 PM CST SAT FEB 22 2014
.DISCUSSION...
300 PM...FORECAST CONCERNS INCLUDE A FEW INCHES OF SNOW ACROSS THE
FAR SOUTHEAST CWA THIS EVENING...A FEW INCHES OF SNOW ACROSS THE
ENTIRE AREA MONDAY NIGHT...AND THE RETURN OF ARCTIC AIR NEXT WEEK.
BAND OF PRECIP HAS DEVELOPED OVER THE FAR SOUTHEAST CWA THIS
AFTERNOON AND THIS HAS BEEN SHOWN FAIRLY WELL AND CONSISTENTLY ON
THE SHORT TERM/HI RES GUIDANCE. THE CONTINUED TREND IS TO HAVE
THIS BAND PUSH SOUTHEAST OF THE CWA DURING THE MID EVENING HOURS.
ONLY CHANGE FROM THE UPDATE EARLIER TODAY IS TO TIGHTEN THE POP
GRADIENT A BIT WITH THE A SLIGHT CHANCE OF SNOW ABOUT TO THE
KANKAKEE RIVER...DRY NORTH OF THERE. TIMING-WISE...ITS POSSIBLE
THAT THIS BAND COULD DRIFT SOUTHEAST OF THE CWA SOONER RATHER THAN
LATER AND SHOULD THAT HAPPEN...AMOUNTS COULD BE A BIT LOWER WITH 1
TO 3 INCHES CURRENTLY EXPECTED GENERALLY SOUTH OF A PIPER CITY TO
A RENSSELAER LINE.
A RIDGE OF HIGH PRESSURE WILL BUILD FROM THE NORTHERN PLAINS
TONIGHT TO THE SOUTHERN LAKES AND OHIO VALLEY SUNDAY INTO SUNDAY
NIGHT. THIS WILL MARK THE BEGINNING OF A DOWNWARD TREND IN TEMPS
AS HIGHS ON SUNDAY ONLY REACH THE MID/UPPER 20S WITH HIGHS A FEW
DEGREES LOWER AGAIN ON MONDAY. HOWEVER...DRY CONDITIONS ARE
EXPECTED THROUGH MONDAY AFTERNOON.
THE NEXT CHANCE OF SNOW HAS BEEN DELAYED SLIGHTLY TO MONDAY NIGHT
AND HAVE GENERALLY FOLLOWED THE ECMWF WHICH HAS BEEN THE MOST
CONSISTENT AND SHOWS A SWATH OF QPF OF A TENTH OF AN INCH OR SO.
GIVEN THE COLD TEMPS DURING THIS TIME PERIOD...THE SNOW WILL BE
QUITE DRY/FLUFFY AND A FEW INCHES OF ACCUMULATION STILL APPEAR ON
TRACK AND HAVE INCREASED POPS BACK TO LIKELY FOR THIS TIME PERIOD.
WITH THE SLOWER ARRIVAL...LIGHT SNOW MAY PERSIST INTO TUESDAY
MORNING AND HAVE INTRODUCED LOW CHANCE POPS.
FIRST PUNCH OF COLD AIR THEN ARRIVES TUESDAY/TUESDAY NIGHT AS
LOWS DROP INTO THE LOW SINGLE DIGITS...LIKELY BELOW ZERO ACROSS
THE NORTHWEST CWA. LOW PRESSURE THEN PASSES ACROSS THE NORTHERN
LAKES WEDNESDAY AFTERNOON/EVENING WITH A COLD FRONT PUSHING ACROSS
THE REGION WEDNESDAY EVENING. THIS WILL BRING THE SECOND PUNCH OF
COLDER AIR WITH 850MB TEMPS STILL PROGGED INTO THE -22C TO -26C
RANGE. CONTINUED LOW SINGLE DIGITS TO BELOW ZERO TEMPS ARE
EXPECTED BOTH THURSDAY MORNING AND AGAIN FRIDAY MORNING. HIGHS
DURING THIS TIME ARE SOMEWHAT MORE UNCERTAIN DUE TO STRONGER LATE
FEBRUARY SUNSHINE...BUT WILL BE 15-25 DEGREES BELOW NORMAL. CMS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 22Z...
* NONE.
RC
//DISCUSSION...UPDATED 18Z...
GOOD FORCING FOR LIFT NORTH OF A EAST-WEST FRONTAL BOUNDARY ACROSS
SOUTHERN ILLINOIS AND SOUTHERN INDIANA WILL CAUSE A NARROW BAND OF
SNOW TO DEVELOP THIS AFTERNOON AND CONTINUE INTO THE EVENING WELL
SOUTH OF INTERSTATE 80. MID AND HI CLOUDS WILL PREVAIL NORTH OF
THIS SNOW ACROSS ORD/MDW AND ALL OF CHICAGO. MAY SEE A FEW
FLURRIES AS THE MID DECK LOWERS SOMEWHAT... BUT EXPECT CIGS TO
REMAIN ABOVE 4500 FT AND VSBYS P6SM THROUGH THE AFTERNOON AND
EVENING.
HIGH PRESSURE RIDGING INCREASES OVERNIGHT INTO SUNDAY AS A HIGH
BUILDS SOUTHEAST FROM THE PLAINS.
ED F
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* HIGH FOR ALL ELEMENTS.
RC
//OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z...
SUNDAY NIGHT...VFR.
MONDAY...CHC SNOW...ESPECIALLY LATE.
TUESDAY THROUGH FRIDAY...VFR.
BMD
&&
.MARINE...
148 PM CST
LOW PRESSURE CENTERED NEAR JAMES BAY THIS AFTERNOON CONTINUES TO
PRODUCE WINDS OF 25 TO 30 KT ACROSS THE LAKE THIS AFTERNOON. THIS
LOW WILL GRADUALLY WEAKEN THROUGH THE REMAINDER OF THE WEEKEND.
HOWEVER...WESTERLY WINDS WILL CONTINUE IN THE 20 TO 30 KT RANGE
SUNDAY INTO MONDAY AS THE SURFACE GRADIENT REMAINS ELEVATED IN
ADVANCE OF A BROAD RIDGE OF SURFACE HIGH PRESSURE EXTENDING FROM THE
NORTHERN PLAINS TO THE OHIO VALLEY.
THE NEXT POTENTIAL HEADLINE WORTHY WIND EVENT WILL BE AROUND THE
MIDDLE OF NEXT WEEK. A FEW CLIPPER TYPE SYSTEMS ARE EXPECTED TO DROP
SOUTHEASTWARD ACROSS THE LAKES REGION DURING THIS PERIOD. OF THESE
NUMEROUS CLIPPER SYSTEMS...IT APPEARS THAT A POTENT ONE WILL
DROP ACROSS THE REGION WEDNESDAY NIGHT. THIS SYSTEM COULD PRODUCE A
PERIOD OF SOUTHWESTERLY GALES ON WEDNESDAY...FOLLOWED BY A PERIOD OF
POTENTIALLY HIGH END NORTHWESTERLY GALES IN ITS WAKE WEDNESDAY NIGHT
INTO THURSDAY. WITH ANOTHER DEEP ARCTIC SURGE OF COLD AIR EXPECTED
IN THE WAKE OF THIS SECOND CLIPPER...THERE WILL ALSO LIKELY BE
SIGNIFICANT FREEZING SPRAY IN CONJUNCTION WITH THE STRONG
NORTHWESTERLY GALES WEDNESDAY NIGHT INTO THURSDAY.
KJB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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Area Forecast Discussion
National Weather Service Lincoln IL
312 PM CST Sat Feb 22 2014
.DISCUSSION...
ISSUED 300 PM CST Sat Feb 22 2014
Light snow or flurries will return this afternoon and this evening
across most of the area. Measurable snow will be mainly confined
to areas east of I-55, with an inch or two possible closer to
Indiana east of Champaign to Mattoon. The next chance of snow
beyond that appears to be late Monday and Monday night north of
Lincoln to Champaign as the next shortwave moves across N IL.
Dry conditions are expected the remainder of the forecast, with a
dry cold frontal passage Wed night ushering in reinforcing cold
air. Below normal temperatures will prevail for much of this 7-day
forecast.
SHORT TERM...Tonight through Monday.
A band of mid-level frontogenesis north of the stationary front
along I-70 will create some lift that will be enhanced by steep
mid-level lapse rates. That should give the virga a boost in
saturating the lower levels. Flurries already started at PIA
around 2 pm after several hours of virga. Satellite pics show a
baroclinic leaf developing ahead of the weak low pressure over
western Missouri. That low is projected to slide east along the
boundary, which should further enhance the thermo-dynamic forcing.
Meso-scale bands of precip are being advertised by the HRRR and
NMM-east. Light snow will be north of Mattoon to Paris with some
rain or rain-snow mix south of there. We could see an inch or two
of snow where the band of snow rotates and lingers across our
east-central counties...bounded by a line from Decatur to
Hoopeston in the north and Taylorville to Mattoon to Paris in the
south. Even in this late hour, many differences exist with the
placement and intensity of any meso-scale bands of precip late
this afternoon and evening. The GFS and Canadian GEM are more
aggressive with snow, while the NAM is the weakest and the ECMWF
is in the middle. We increased PoPs to categorical and likely in
areas with an inch or more snow possible, with high chance
bordering that. Accums are a tough call with this much dry air to
overcome, but forcing looks strong enough for a short duration to
get some light accumulation.
Precip should progress eastward after midnight, and come to an end
for our counties by 3 am. Colder air will begin to advance into C
IL with the surface high, which should help lows across the north
drop into the teens. Clouds will temper the cool-down, as southern
areas remain in the low 30s.
The 12z Canadian has increased potential for snow or rn/sn as a
shortwave advances east, just north of the stationary front. The
ECMWF is also showing some forcing across our southern counties,
but lower RH and no precip. After coord with offices to the south,
we decided to just add sprinkles and flurries for now on Sunday.
Mostly clear skies for much of Sunday night will provide better
radiational cooling conditions, and lows will respond by dropping
into the single digits north of Peoria.
Monday afternoon and evening will see a 125kt jet at 250mb help
push a shortwave across northern IL. Light snow will develop
mainly north of a line from Rushville to Champaign...with a
dusting along the line to as much as an inch from Galesburg to
El Paso. The NAM is the main outlier with this period of snow,
with much less forcing and farther south than the
GFS/ECMWF/Canadian. We went with consensus and increased PoPs to
likely across Knox to Woodford counties Monday eve.
LONG TERM...Tuesday through Saturday.
We are not expected any measurable precip through the extended
forecast as colder air prevails. A dry cold frontal passage on Wed
night will aid in keeping temps well below normal. Lows will dip
below zero across our northern area on Tuesday night, and get very
close to zero in the north Wed night and Thurs night. Highs will
struggle to climb out of the teens north of I-72 on Wed. Gradual
warming will develop from Thurs to Saturday, but even Saturday`s
highs will range from mid 20s north to mid 30s south, or about 10
to 15 deg below normal.
Shimon
&&
.AVIATION...
ISSUED 1142 AM CST Sat Feb 22 2014
Main concern will be in the 22Z through 06Z time frame, as a band
of precipitation is expected to develop across central Illinois.
Most of the lower levels are dry now, but ceilings lowering to
around 4000 feet west of KPIA indicating some moistening taking
place. High-resolution models showing potentially some light rain
or snow late afternoon near KPIA/KBMI, but main band expected to
set up in the general KSPI-KCMI corridor and persist into mid
evening. Precip type will be a question early on as temperatures
down in this area have reached the 40s, but will drop quickly as
the precipitation becomes steadier. Have hit KCMI and KDEC the
hardest with TEMPO periods of IFR ceilings and visibilities early
this evening when it will be all snow and potential mesoscale
features enhance the precipitation intensity, but this
potentially may extend as far west as KSPI. Most of the snow
should be out of the TAF sites by around 06Z, although it will
still be close to the south.
Geelhart
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
150 PM CST SAT FEB 22 2014
.DISCUSSION...
1042 AM CST
WE HAVE MADE SOME CHANGES TO THE FORECAST FOR THIS AFTERNOON AND
EVENING. REGIONAL RADAR IMAGERY THIS MORNING HAS SHOWN SOME DECENT
RETURNS BLOSSOMING ACROSS FAR SOUTHERN IOWA AND INTO WEST CENTRAL
ILLINOIS. THIS ACTIVITY APPEARS TO BE DEVELOPING IN ASSOCIATION
WITH AN ENHANCED BAND OF MID-LEVEL FRONTOGENESIS...WHICH IS
SETTING UP TO THE NORTH OF A STATIONARY WEST TO EAST ORIENTED
FRONTAL BOUNDARY.
THE MORNING RAOBS ACROSS THE AREA...NAMELY AT KDVN AND
KILX...INDICATE THE PRESENCE OF VERY STEEP MID LEVEL LAPSE
RATES...WHICH IS LIKELY ENHANCING THE EFFICIENCY OF THE FRONTAL
SCALE FORCING. HOWEVER...THE PROFILES ARE ALSO FAIRLY DRY IN THE
LOWER LEVELS. THEREFORE...IN SPITE OF THESE DECENT RETURNS
SHOWING UP ON RADAR...MOST IF NOT ALL OF THE CURRENT ACTIVITY IS
LIKELY NOT REACHING THE GROUND YET. OBSERVATIONS ACROSS THIS AREA
HAVE SHOWN A DOWNWARD TREND IN CIG HEIGHTS OVER THE PAST COUPLE OF
HOURS...INDICATING THAT THE PROFILE IS GRADUALLY MOISTENING. SO IT
APPEARS TO BE A MATTER OF TIME BEFORE PRECIP STARTS TO REACH THE
SURFACE.
MODEL GUIDANCE SUGGESTS THAT THIS BAND OF STRONG FRONTOGENESIS
WILL SET UP ACROSS MY SOUTHERN CWA THIS AFTERNOON AND INTO THIS
EVENING...LIKELY SUPPORTING A NARROW BUT RATHER INTENSE AREA OF
FORCING FOR ASCENT THROUGH THE DGZ. GIVEN THIS FORCING SHOULD
CORRESPOND WITH THOSE STEEP MID LEVEL LAPSE RATES NOTED IN THE
MORNING RAOBS...THIS HAS THE POTENTIAL TO RESULT IN BANDING OF
HEAVY SNOW ACROSS AT LEAST A SMALL PORTION OF CENTRAL ILLINOIS
AND INTO INDIANA THIS AFTERNOON AND EVENING.
THE MAIN QUESTION IS WHERE EXACTLY THIS BAND WILL SET UP. MUCH OF
THE HIGH-RES GUIDANCE HAS BEEN JUMPING AROUND A BIT WITH THE
PLACEMENT...SO CONFIDENCE ON THE EXACT AREAS LIKELY TO SEE A BAND
OF HEAVY SNOW REMAINS SOMEWHAT LOW...BUT THE COMBINATION OF
CURRENT OBS AND MODEL GUIDANCE IS POINTING AT SOME OF MY FAR
SOUTHERN COUNTIES...FROM FORD AND IROQUOIS INTO BENTON COUNTY
INDIANA AND POINTS SOUTH. IN THESE AREAS...THERE COULD BE A NARROW
CONFINED BAND OF 2 TO 5 INCHES OF SNOW....WITH MUCH LIGHTER
AMOUNTS OF AN INCH OR TWO POSSIBLE OUTSIDE OF THE BAND OF HEAVIEST
SNOW. GIVEN MY CURRENT CONFIDENCE ON THE PLACEMENT OF THE HEAVIEST
BAND OF SNOW...AND EVEN THE POSSIBILITY THAT IT STAYS JUST SOUTH
OF MY AREA...I HAVE REMAINED RATHER CONSERVATIVE WITH SNOW AMOUNTS
AND POPS IN MY FAR SOUTH. I DID RAISE POPS INTO THE LOW END LIKELY
CATEGORY WITH MENTIONS OF UP TO 2 INCHES OF SNOW IN MY FAR SOUTH.
THIS MAY NEED TO BE REFINED THIS AFTERNOON AS IT BEGINS SETTING UP
ACROSS THE AREA.
KJB
//PREV DISCUSSION...
249 AM CST
TODAY...
RELATIVELY QUIET WEATHER THIS MORNING...WITH BROAD ANTI-CYCLONIC
FLOW POSITIONED OVER THE MID-MISSOURI VALLEY. THIS HAS ALLOWED SKIES
TO BECOME MOSTLY CLEAR FOR THE FORECAST AREA. FURTHER NORTH THE
POTENT LOW PRESSURE REMAINS WRAPPED UP OVER HUDSON BAY WITH A WEAK
LOBE OF VORTICITY PIVOTING EAST ACROSS NORTHERN WISC AND GENERATING
SOME FLURRIES/LGT SNOW EARLY THIS MORNING. IR IMAGERY SHOWS THE NEXT
MID-LVL WAVE TRYING TO PUSH EAST ACROSS THE CENTRAL PLAINS...HOWEVER
BASED ON SFC OBS MOISTURE CONTINUES TO BE LACKING. CLOUD BASES
REMAIN ABOVE 7KFT AGL FOR MOST POINTS ACROSS THE CENTRAL
PLAINS...DESPITE WHAT SOME GUIDANCE INDICATES SHOULD BE SHOWING
FURTHER MOISTENING AND LOWERING WITH SPOTTY PRECIP DEVELOPING. THIS
WAVE IS POISED TO PUSH EAST AND ARRIVE ACROSS THE FORECAST AREA THIS
MORNING. FORCING REMAINS LACKING IN ADDITION THE ENVIRONMENT IS VERY
DRY...SOUNDINGS CONTINUE TO INDICATE SOME MOISTENING...ALTHOUGH
EXPECT THE ANTI-CYCLONIC FLOW TO KEEP PRECIP LIMITED TO SPRINKLES OR
FLURRIES MAINLY SOUTH OF I-88. LOCAL ARW8KM MODEL SUGGESTS JUST SOME
MID-LVL CLOUDS WITH THIS FEATURE.
EXPECT SKIES TO REMAIN P-CLOUDY TODAY...AND WITH TEMPS ALOFT
HOVERING ARND -4 TO -6 DEG C...SFC TEMPS SHUD BE ABLE TO WARM
GENERALLY INTO THE 30S AND POSSIBLY ARND 40 SOUTH OF PONTIAC TO
KANKAKEE.
TONIGHT...
SFC RIDGE REMAINS OVER THE REGION...AS A MID-LVL TROUGH BEGINS TO
PUSH AN ENHANCED LOBE OF VORTICITY INTO THE UPPER MIDWEST. WITH A
BAROCLINIC ZONE ORIENTED FROM CENTRAL MISSOURI STRETCHING NORTHEAST
THROUGH CENTRAL IL/NORTHERN IN...EXPECT THIS WILL PROVIDE SOME ADDED
LIFT/MOISTURE INTO THIS AREA AND MAY HELP TO SPAWN SOME BETTER
ORGANIZED PRECIP TONIGHT FOR THE SOUTHERN PORTIONS OF THE FORECAST
AREA. AS THE MID-LVL VORT LOBE PUSHES EAST...THIS WILL HELP TO PUSH
THE POPS/MOISTURE FURTHER EAST JUST BEFORE DAYBREAK SUN.
TEMPS WILL RADIATE OVERNIGHT INTO THE TEENS...TO LOW 20S CLOSER TO
WHERE PRECIP/CLOUDS ARE EXPECTED TONIGHT ALONG AND SOUTH OF LASALLE
TO VALPARAISO.
CONFIDENCE...HIGH.
SUNDAY THROUGH MONDAY...
500MB RIDGE OFF THE PAC-NW COAST BEGINS TO SHOW SIGNS OF AMPLIFYING
AS THE DOWNSTREAM MID-LVL TROUGH/VORT STRENGTHENS SUN. THE TROUGH
OVER THE GREAT LAKES REGION BECOMES RELATIVELY FLAT...ALLOWING FOR A
BRIEF SEMI-ZONAL FLOW SUN/MON OVER THE FORECAST AREA.
SFC RIDGING BECOMES ELONGATED STRETCHING FROM CENTRAL CANADA
SOUTHEAST THROUGH THE TENN VALLEY. THIS WILL REMAIN OVER THE REGION
SUN/MON...KEEPING PRECIP CHCS TO A MINIMUM. THE MID-LVL VORT MAX
BEGINS TO DIP SOUTH FROM CENTRAL CANADA MON AFTN...WITH GUIDANCE
PROGGING A SFC WAVE DEVELOPING OVER THE LEE-SIDE OF THE ROCKIES.
THIS FEATURE HAS SLOWED IN ARRIVAL ACROSS THE FORECAST AREA UNTIL
CLOSER TO MON NGT/TUE. HAVE PUSHED POPS BACK UNTIL MON NGT...AS THIS
BOUNDARY BECOMES SLIGHTLY MORE ACTIVE. ALTHOUGH EXPECT ONLY LGT SNOW
WITH ANY ACCUMS REMAINING LESS THAN ONE HALF INCH AT THIS TIME.
TEMPS SUN WILL REMAIN UNSEASONABLY COOL...ALTHOUGH HOW THIS SEASON
HAS GONE IT HAS BECOME THE NORM...WITH TEMPS HOVERING IN THE 20S.
THEN FOR MON TEMPS HOLD IN THE UPR TEENS TO LOW 20S.
CONFIDENCE...HIGH.
TUESDAY THROUGH FRIDAY...
THE PATTERN IN THE EXTENDED PERIODS CONTINUES TO FEATURE A RETURN TO
HIGH AMPLITUDE RIDGING OVER WESTERN CANADA/YUKON...RESULTING IN A
DOWNSTREAM DIGGING TROUGH OVER THE GREAT LAKES REGION. GIVEN HOW
ENSEMBLES HAVE CONTINUED TO DEMONSTRATE MINIMAL SPREAD...CONFIDENCE
REMAINS HIGH THAT A SLUG OF ARCTIC AIR WILL BREAK SOUTH FROM THE
ARCTIC CIRCLE AND SLIDE SOUTH ACROSS CENTRAL CANADA TUE. GUIDANCE
CURRENTLY INDICATES 850MB THERMAL TROUGH OF -20 TO -24 DEG C
ARRIVING OVER THE FORECAST AREA TUE NGT/WED...ACCOMPANIED BY A
ROBUST SFC RIDGE POISED TO PUSH INTO THE CENTRAL PLAINS AND MAINTAIN
A NORTH LLVL FLOW WITH COLD AIR ADVECTING INTO NORTHERN IL/NORTHWEST
IN MID/LATE WEEK. THIS SUGGESTS TEMPS WED WILL STRUGGLE TO WARM
BEYOND THE SINGLE DIGITS...POSSIBLY REACHING THE LOW TEENS. THIS
SHOULD BE SIMILAR FOR THUR.
LATE WEEK THE SFC RIDGE WILL DRIFT SOUTH...ALLOWING LLVL FLOW TO
TURN WEST TO SOUTHWEST AND BRIEFLY ALLOW TEMPS TO WARM BACK INTO THE
TEENS/LOW 20S FRI. HOWEVER ENSEMBLES SUGGEST THIS MAY ONLY BE
TEMPORARY. THE MID-LVL VORT RETROGRADES...WITH A SECONDARY SURGE OF
ARCTIC AIR POISED TO RETURN FOR THE FOLLOWING WEEKEND. AT THIS TIME
MOST OF THE EXTENDED PERIODS WILL REMAIN DRY FROM PERSISTING SFC
RIDGING.
CONFIDENCE IN TEMPS...HIGH.
CONFIDENCE IN DRY WX FOR MOST OF THE EXTENDED...MEDIUM.
BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* CHANCE OF FLURRIES THROUGH THE AFTERNOON... WHILE ANY
ACCUMULATIONG SNOW WILL STAY WELL SOUTH OF THE TERMINALS.
* CIGS WILL REMAIN VFR AND VSBYS UNRESTRUCTED THROUGH TONIGHT.
* WINDS FROM THE WEST WILL OCCASIONALLY GUST THIS AFTERNOON... AND
EASE BACK TO CONSISTANTLY BELOW 10 KTS TONIGHT.
ED F
//DISCUSSION...UPDATED 18Z...
GOOD FORCING FOR LIFT NORTH OF A EAST-WEST FRONTAL BOUNDARY ACROSS
SOUTHERN ILLINOIS AND SOUTHERN INDIANA WILL CAUSE A NARROW BAND OF
SNOW TO DEVELOP THIS AFTERNOON AND CONTINUE INTO THE EVENING WELL
SOUTH OF INTERSTATE 80. MID AND HI CLOUDS WILL PREVAIL NORTH OF
THIS SNOW ACROSS ORD/MDW AND ALL OF CHICAGO. MAY SEE A FEW
FLURRIES AS THE MID DECK LOWERS SOMEWHAT... BUT EXPECT CIGS TO
REMAIN ABOVE 4500 FT AND VSBYS P6SM THROUGH THE AFTERNOON AND
EVENING.
HIGH PRESSURE RIDGING INCREASES OVERNIGHT INTO SUNDAY AS A HIGH
BUILDS SOUTHEAST FROM THE PLAINS.
ED F
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* HIGH CONFIDENCE THAT ACCUMULATING SNOW WILL STAY SOUTH OF
ORD/MDW.
* HIGH CONFIDENCE IN REMAINING FORECAST ELEMENTS.
ED F
//OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z...
SUNDAY NIGHT...VFR.
MONDAY...CHC SNOW...ESPECIALLY LATE.
TUESDAY THROUGH FRIDAY...VFR.
BMD
&&
.MARINE...
148 PM CST
LOW PRESSURE CENTERED NEAR JAMES BAY THIS AFTERNOON CONTINUES TO
PRODUCE WINDS OF 25 TO 30 KT ACROSS THE LAKE THIS AFTERNOON. THIS
LOW WILL GRADUALLY WEAKEN THROUGH THE REMAINDER OF THE WEEKEND.
HOWEVER...WESTERLY WINDS WILL CONTINUE IN THE 20 TO 30 KT RANGE
SUNDAY INTO MONDAY AS THE SURFACE GRADIENT REMAINS ELEVATED IN
ADVANCE OF A BROAD RIDGE OF SURFACE HIGH PRESSURE EXTENDING FROM THE
NORTHERN PLAINS TO THE OHIO VALLEY.
THE NEXT POTENTIAL HEADLINE WORTHY WIND EVENT WILL BE AROUND THE
MIDDLE OF NEXT WEEK. A FEW CLIPPER TYPE SYSTEMS ARE EXPECTED TO DROP
SOUTHEASTWARD ACROSS THE LAKES REGION DURING THIS PERIOD. OF THESE
NUMEROUS CLIPPER SYSTEMS...IT APPEARS THAT A POTENT ONE WILL
DROP ACROSS THE REGION WEDNESDAY NIGHT. THIS SYSTEM COULD PRODUCE A
PERIOD OF SOUTHWESTERLY GALES ON WEDNESDAY...FOLLOWED BY A PERIOD OF
POTENTIALLY HIGH END NORTHWESTERLY GALES IN ITS WAKE WEDNESDAY NIGHT
INTO THURSDAY. WITH ANOTHER DEEP ARCTIC SURGE OF COLD AIR EXPECTED
IN THE WAKE OF THIS SECOND CLIPPER...THERE WILL ALSO LIKELY BE
SIGNIFICANT FREEZING SPRAY IN CONJUNCTION WITH THE STRONG
NORTHWESTERLY GALES WEDNESDAY NIGHT INTO THURSDAY.
KJB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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Area Forecast Discussion
National Weather Service Lincoln IL
1142 AM CST Sat Feb 22 2014
.DISCUSSION...
ISSUED 1035 AM CST Sat Feb 22 2014
Extensive band of altocumulus showing up on regional radar
mosaics, from along the Iowa/Missouri border east to near
Danville. Nothing is reaching the ground yet, as there are still
pretty good temperature/dew point spreads in this corridor.
However, main concern will be with increase in isentropic lift
through the afternoon, as frontogenesis takes place across
southern Missouri into southeast Illinois. While the NAM keeps
things dry through the afternoon, the higher resolution models
such as the RAP, HRRR and Hi-Res-NMM show development of light
precipitation in a couple areas, one north of I-74 and the other
from about Danville southwest through Springfield. The GFS has
been significant more robust with this, indicating around 1/3 inch
of precipitation while the other models are more in the order of a
tenth inch or so depending on mesoscale features. Some of the
lower levels on forecast soundings are rather dry, which could
hold off the precip a bit but also cool the column more quickly to
support a changeover to snow. Have increased PoP`s to around
40-50% east of the Illinois River and north of I-70 for this
afternoon and will need to monitor trends closely for
precipitation type.
Geelhart
&&
.AVIATION...
ISSUED 1142 AM CST Sat Feb 22 2014
Main concern will be in the 22Z through 06Z time frame, as a band
of precipitation is expected to develop across central Illinois.
Most of the lower levels are dry now, but ceilings lowering to
around 4000 feet west of KPIA indicating some moistening taking
place. High-resolution models showing potentially some light rain
or snow late afternoon near KPIA/KBMI, but main band expected to
set up in the general KSPI-KCMI corridor and persist into mid
evening. Precip type will be a question early on as temperatures
down in this area have reached the 40s, but will drop quickly as
the precipitation becomes steadier. Have hit KCMI and KDEC the
hardest with TEMPO periods of IFR ceilings and visibilities early
this evening when it will be all snow and potential mesoscale
features enhance the precipitation intensity, but this
potentially may extend as far west as KSPI. Most of the snow
should be out of the TAF sites by around 06Z, although it will
still be close to the south.
Geelhart
&&
.PREV DISCUSSION...
ISSUED 215 AM CST Sat Feb 22 2014
Weak shortwave that pushed across the area late last evening
produced a few sprinkles over parts of central and east central
Illinois. That wave has shifted off to our east early this morning
with skies clearing from northwest to southeast. However, another
disturbance seen on the water vapor loop over the northern Rockies
with clouds on the increase over parts of western Iowa. At the surface,
a frontal boundary stretched from northern Illinois west through west
central Iowa. This feature is expected to push across our area today
into this evening bringing the threat for some light precipitation.
SHORT TERM...Today through Monday
Main forecast concerns this period were with the upstream shortwave
and its affect on the forecast area with respect to timing and
coverage of precip later this morning or early this afternoon, and
then with precip type issues for tonight.
Deep trof that brought the active weather to our area on Thursday
as north of Lake Superior early this morning with a broad cyclonic
flow prevalent at 500 mb over the Great Lakes. Models coming in line
with respect to the shortwave to our northwest this morning and the
placement of the frontal boundary currently to our northwest. The front
should slide southeast into the area today as the upper wave approaches
from the northwest, setting up a period of light overrunning precip
to the north of the boundary, especially for this afternoon into tonight.
Models have trended a bit more aggressive with the 700-500 mb forcing
for this time period and have thrown out a bit more QPF across the area
as well. Not really sure where this is all coming from as the deeper
moisture has been displaced well off to our east and southeast. However,
as the shortwave drops southeast into the mean long wave trof position,
we should see a bit of amplification with the upper system resulting
in better low and mid level forcing, which may be able to squeeze
out a tenth to two tenths of an inch of QPF.
Forecast soundings off the NAM-WRF suggest a rain snow mix possible
in the north, with soundings too warm to support anything but light
rain this afternoon over the central thru east central areas. As the
frontal boundary slides south of our area by this evening, colder air
will be able to work into the lower levels of the atmosphere which
should change any mix over to light snow from northwest to southeast.
May see around an inch of wet snow over parts of east central Illinois
by later tonight with most of the remainder of the area seeing less
than an inch.
The better 700-500 mb QG forcing and precip threat shifts off to our
east by Sunday morning with another Arctic high situated up across
west central Canada bringing in one of several shots of cold air to
the region over the next week. Today will be the last of the "mild"
days as the colder air moves in starting tonight with temperatures
cooling a few degrees each day heading into Monday. By Monday, another
fast moving shortwave in the northwest flow aloft will approach the
area by evening bringing an increasing chance for light snow to mainly
the north half of the forecast area Monday night, followed by a
reinforcing surge of Arctic air into the middle of next week.
LONG TERM...Tuesday through Friday
Most of the medium range models were on board with the idea of a
another negative height anomaly settling south to near James Bay by
the second half of this forecast period. This should keep our
temperatures well below normal through the period with the main
storm track displaced over the southern Plains eastward through the
Gulf states. Our weather will be coming from the northwest thru most
of this period as shortwaves rotate south and southeast around the
large vortex at 500 mb bringing reinforcing shots of cold air and
chances for light snow or flurries. This far out, timing and magnitude
of these fast moving waves embedded in the northwest flow will be
difficult to forecast so will keep the extended dry for now.
Smith
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1049 AM CST SAT FEB 22 2014
.DISCUSSION...
1042 AM CST
WE HAVE MADE SOME CHANGES TO THE FORECAST FOR THIS AFTERNOON AND
EVENING. REGIONAL RADAR IMAGERY THIS MORNING HAS SHOWN SOME DECENT
RETURNS BLOSSOMING ACROSS FAR SOUTHERN IOWA AND INTO WEST CENTRAL
ILLINOIS. THIS ACTIVITY APPEARS TO BE DEVELOPING IN ASSOCIATION WITH
AN ENHANCED BAND OF MID-LEVEL FRONTOGENESIS...WHICH IS SETTING UP TO
THE NORTH OF A STATIONARY WEST TO EAST ORIENTED FRONTAL BOUNDARY.
THE MORNING RAOBS ACROSS THE AREA...NAMELY AT KDVN AND
KILX...INDICATE THE PRESENCE OF VERY STEEP MID LEVEL LAPSE
RATES...WHICH IS LIKELY ENHANCING THE EFFICIENCY OF THE FRONTAL
SCALE FORCING. HOWEVER...THE PROFILES ARE ALSO FAIRLY DRY IN THE LOWER
LEVELS. THEREFORE...IN SPITE OF THESE DECENT RETURNS SHOWING UP ON
RADAR...MOST IF NOT ALL OF THE CURRENT ACTIVITY IS LIKELY NOT
REACHING THE GROUND YET. OBSERVATIONS ACROSS THIS AREA HAVE SHOWN A
DOWNWARD TREND IN CIG HEIGHTS OVER THE PAST COUPLE OF
HOURS...INDICATING THAT THE PROFILE IS GRADUALLY MOISTENING. SO IT
APPEARS TO BE A MATTER OF TIME BEFORE PRECIP STARTS TO REACH THE
SURFACE.
MODEL GUIDANCE SUGGESTS THAT THIS BAND OF STRONG FRONTOGENESIS WILL
SET UP ACROSS MY SOUTHERN CWA THIS AFTERNOON AND INTO THIS
EVENING...LIKELY SUPPORTING A NARROW BUT RATHER INTENSE AREA OF
FORCING FOR ASCENT THROUGH THE DGZ. GIVEN THIS FORCING SHOULD
CORRESPOND WITH THOSE STEEP MID LEVEL LAPSE RATES NOTED IN THE
MORNING RAOBS...THIS HAS THE POTENTIAL TO RESULT IN BANDING OF HEAVY
SNOW ACROSS AT LEAST A SMALL PORTION OF CENTRAL ILLINOIS AND INTO
INDIANA THIS AFTERNOON AND EVENING.
THE MAIN QUESTION IS WHERE EXACTLY THIS BAND WILL SET UP. MUCH OF
THE HIGH-RES GUIDANCE HAS BEEN JUMPING AROUND A BIT WITH THE
PLACEMENT...SO CONFIDENCE ON THE EXACT AREAS LIKELY TO SEE A BAND OF
HEAVY SNOW REMAINS SOMEWHAT LOW...BUT THE COMBINATION OF CURRENT OBS
AND MODEL GUIDANCE IS POINTING AT SOME OF MY FAR SOUTHERN
COUNTIES...FROM FORD AND IROQUOIS INTO BENTON COUNTY INDIANA AND
POINTS SOUTH. IN THESE AREAS...THERE COULD BE A NARROW CONFINED BAND OF 2
TO 5 INCHES OF SNOW....WITH MUCH LIGHTER AMOUNTS OF AN INCH OR TWO
POSSIBLE OUTSIDE OF THE BAND OF HEAVIEST SNOW. GIVEN MY CURRENT
CONFIDENCE ON THE PLACEMENT OF THE HEAVIEST BAND OF SNOW...AND EVEN
THE POSSIBILITY THAT IT STAYS JUST SOUTH OF MY AREA...I HAVE
REMAINED RATHER CONSERVATIVE WITH SNOW AMOUNTS AND POPS IN MY FAR
SOUTH. I DID RAISE POPS INTO THE LOW END LIKELY CATEGORY WITH
MENTIONS OF UP TO 2 INCHES OF SNOW IN MY FAR SOUTH. THIS MAY NEED TO
BE REFINED THIS AFTERNOON AS IT BEGINS SETTING UP ACROSS THE
AREA.
KJB
&&
.PREV DISCUSSION...
249 AM CST
TODAY...
RELATIVELY QUIET WEATHER THIS MORNING...WITH BROAD ANTI-CYCLONIC
FLOW POSITIONED OVER THE MID-MISSOURI VALLEY. THIS HAS ALLOWED SKIES
TO BECOME MOSTLY CLEAR FOR THE FORECAST AREA. FURTHER NORTH THE
POTENT LOW PRESSURE REMAINS WRAPPED UP OVER HUDSON BAY WITH A WEAK
LOBE OF VORTICITY PIVOTING EAST ACROSS NORTHERN WISC AND GENERATING
SOME FLURRIES/LGT SNOW EARLY THIS MORNING. IR IMAGERY SHOWS THE NEXT
MID-LVL WAVE TRYING TO PUSH EAST ACROSS THE CENTRAL PLAINS...HOWEVER
BASED ON SFC OBS MOISTURE CONTINUES TO BE LACKING. CLOUD BASES
REMAIN ABOVE 7KFT AGL FOR MOST POINTS ACROSS THE CENTRAL
PLAINS...DESPITE WHAT SOME GUIDANCE INDICATES SHOULD BE SHOWING
FURTHER MOISTENING AND LOWERING WITH SPOTTY PRECIP DEVELOPING. THIS
WAVE IS POISED TO PUSH EAST AND ARRIVE ACROSS THE FORECAST AREA THIS
MORNING. FORCING REMAINS LACKING IN ADDITION THE ENVIRONMENT IS VERY
DRY...SOUNDINGS CONTINUE TO INDICATE SOME MOISTENING...ALTHOUGH
EXPECT THE ANTI-CYCLONIC FLOW TO KEEP PRECIP LIMITED TO SPRINKLES OR
FLURRIES MAINLY SOUTH OF I-88. LOCAL ARW8KM MODEL SUGGESTS JUST SOME
MID-LVL CLOUDS WITH THIS FEATURE.
EXPECT SKIES TO REMAIN P-CLOUDY TODAY...AND WITH TEMPS ALOFT
HOVERING ARND -4 TO -6 DEG C...SFC TEMPS SHUD BE ABLE TO WARM
GENERALLY INTO THE 30S AND POSSIBLY ARND 40 SOUTH OF PONTIAC TO
KANKAKEE.
TONIGHT...
SFC RIDGE REMAINS OVER THE REGION...AS A MID-LVL TROUGH BEGINS TO
PUSH AN ENHANCED LOBE OF VORTICITY INTO THE UPPER MIDWEST. WITH A
BAROCLINIC ZONE ORIENTED FROM CENTRAL MISSOURI STRETCHING NORTHEAST
THROUGH CENTRAL IL/NORTHERN IN...EXPECT THIS WILL PROVIDE SOME ADDED
LIFT/MOISTURE INTO THIS AREA AND MAY HELP TO SPAWN SOME BETTER
ORGANIZED PRECIP TONIGHT FOR THE SOUTHERN PORTIONS OF THE FORECAST
AREA. AS THE MID-LVL VORT LOBE PUSHES EAST...THIS WILL HELP TO PUSH
THE POPS/MOISTURE FURTHER EAST JUST BEFORE DAYBREAK SUN.
TEMPS WILL RADIATE OVERNIGHT INTO THE TEENS...TO LOW 20S CLOSER TO
WHERE PRECIP/CLOUDS ARE EXPECTED TONIGHT ALONG AND SOUTH OF LASALLE
TO VALPARAISO.
CONFIDENCE...HIGH.
SUNDAY THROUGH MONDAY...
500MB RIDGE OFF THE PAC-NW COAST BEGINS TO SHOW SIGNS OF AMPLIFYING
AS THE DOWNSTREAM MID-LVL TROUGH/VORT STRENGTHENS SUN. THE TROUGH
OVER THE GREAT LAKES REGION BECOMES RELATIVELY FLAT...ALLOWING FOR A
BRIEF SEMI-ZONAL FLOW SUN/MON OVER THE FORECAST AREA.
SFC RIDGING BECOMES ELONGATED STRETCHING FROM CENTRAL CANADA
SOUTHEAST THROUGH THE TENN VALLEY. THIS WILL REMAIN OVER THE REGION
SUN/MON...KEEPING PRECIP CHCS TO A MINIMUM. THE MID-LVL VORT MAX
BEGINS TO DIP SOUTH FROM CENTRAL CANADA MON AFTN...WITH GUIDANCE
PROGGING A SFC WAVE DEVELOPING OVER THE LEE-SIDE OF THE ROCKIES.
THIS FEATURE HAS SLOWED IN ARRIVAL ACROSS THE FORECAST AREA UNTIL
CLOSER TO MON NGT/TUE. HAVE PUSHED POPS BACK UNTIL MON NGT...AS THIS
BOUNDARY BECOMES SLIGHTLY MORE ACTIVE. ALTHOUGH EXPECT ONLY LGT SNOW
WITH ANY ACCUMS REMAINING LESS THAN ONE HALF INCH AT THIS TIME.
TEMPS SUN WILL REMAIN UNSEASONABLY COOL...ALTHOUGH HOW THIS SEASON
HAS GONE IT HAS BECOME THE NORM...WITH TEMPS HOVERING IN THE 20S.
THEN FOR MON TEMPS HOLD IN THE UPR TEENS TO LOW 20S.
CONFIDENCE...HIGH.
TUESDAY THROUGH FRIDAY...
THE PATTERN IN THE EXTENDED PERIODS CONTINUES TO FEATURE A RETURN TO
HIGH AMPLITUDE RIDGING OVER WESTERN CANADA/YUKON...RESULTING IN A
DOWNSTREAM DIGGING TROUGH OVER THE GREAT LAKES REGION. GIVEN HOW
ENSEMBLES HAVE CONTINUED TO DEMONSTRATE MINIMAL SPREAD...CONFIDENCE
REMAINS HIGH THAT A SLUG OF ARCTIC AIR WILL BREAK SOUTH FROM THE
ARCTIC CIRCLE AND SLIDE SOUTH ACROSS CENTRAL CANADA TUE. GUIDANCE
CURRENTLY INDICATES 850MB THERMAL TROUGH OF -20 TO -24 DEG C
ARRIVING OVER THE FORECAST AREA TUE NGT/WED...ACCOMPANIED BY A
ROBUST SFC RIDGE POISED TO PUSH INTO THE CENTRAL PLAINS AND MAINTAIN
A NORTH LLVL FLOW WITH COLD AIR ADVECTING INTO NORTHERN IL/NORTHWEST
IN MID/LATE WEEK. THIS SUGGESTS TEMPS WED WILL STRUGGLE TO WARM
BEYOND THE SINGLE DIGITS...POSSIBLY REACHING THE LOW TEENS. THIS
SHOULD BE SIMILAR FOR THUR.
LATE WEEK THE SFC RIDGE WILL DRIFT SOUTH...ALLOWING LLVL FLOW TO
TURN WEST TO SOUTHWEST AND BRIEFLY ALLOW TEMPS TO WARM BACK INTO THE
TEENS/LOW 20S FRI. HOWEVER ENSEMBLES SUGGEST THIS MAY ONLY BE
TEMPORARY. THE MID-LVL VORT RETROGRADES...WITH A SECONDARY SURGE OF
ARCTIC AIR POISED TO RETURN FOR THE FOLLOWING WEEKEND. AT THIS TIME
MOST OF THE EXTENDED PERIODS WILL REMAIN DRY FROM PERSISTING SFC
RIDGING.
CONFIDENCE IN TEMPS...HIGH.
CONFIDENCE IN DRY WX FOR MOST OF THE EXTENDED...MEDIUM.
BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* CHANCE OF A FEW FLURRIES THROUGH AFTERNOON... ACCUMULATING SNOW
STAYING SOUTH OF THE TERMINALS... THIS AFTERNOON AND EVENING.
* CIGS REMAINING VFR AND VSBYS UNRESTRICTED TODAY-TONIGHT.
* WINDS FROM THE WEST OCCASIONALLY GUSTY THROUGH AFTERNOON.
ED F
//DISCUSSION...UPDATED 12Z...
HIGH PRESSURE WILL BUILD IN FROM THE WEST TODAY WITH PRIMARILY VFR
CONDITIONS EXPECTED AND WESTERLY WINDS. A WAVE MOVING EAST ACROSS
IOWA IS PROGGED TO DISSIPATE AS IT MOVES EAST INTO DRY AIR...HOWEVER
SEVERAL MODELS SUGGEST SNOW WILL REDEVELOP THIS AFTERNOON NORTH OF A
WEAK SURFACE WAVE PUSHING ACROSS THE MID MISSISSIPPI VALLEY. MOST
MODELS KEEP PRECIP SOUTH OF THE TERMINALS...THOUGH POSSIBLY CLOSE TO
MDW/GYY...HOWEVER LACK OF UPPER LEVEL SUPPORT AND DRY AIR IN PLACE
ACROSS NORTHERN ILLINOIS WILL MAKE IT DIFFICULT FOR ANY PRECIP TO
REACH THE TERMINALS AND FOR NOW WILL NOT INCLUDE IN TAFS.
BMD
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* MEDIUM TO HIGH CONFIDENCE THAT ACCUMULATING SNOW WILL STAY SOUTH
OF ORD/MDW.
* HIGH CONFIDENCE IN REMAINING FORECAST ELEMENTS.
ED F
//OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z...
SUNDAY NIGHT...VFR.
MONDAY...CHC SNOW...ESPECIALLY LATE.
TUESDAY THROUGH FRIDAY...VFR.
BMD
&&
.MARINE...
304 AM CST
EXPECT TO ENTER A PERIOD OF FAIRLY STEADY STATE CONDITIONS ACROSS
LAKE MICHIGAN WITH MODERATE WESTERLY WINDS EXPECTED THIS WEEKEND
THROUGH MIDWEEK. AN ELONGATED RIDGE IS PROGGED TO BUILD AND REMAIN
ANCHORED FROM THE CANADIAN PRAIRIES INTO THE OHIO VALLEY WHILE LOW
PRESSURE FILLS OVER EASTERN CANADA. WINDS WILL CONTINUE TO EASE
BELOW GALE FORCE EARLY THIS MORNING...HOWEVER...EXPECT WINDS TO
REMAIN AT 30 KT THROUGH MUCH OF THE DAY. WINDS WILL FLUCTUATE
SOME...BUT GENERALLY WILL MAINTAIN A WESTERLY COMPONENT WITH GUSTS
BETWEEN 20 TO 30 KT THROUGH WEDNESDAY...THEN BECOMING MORE NW TO N
THURSDAY AS LOW PRESSURE DIVES FROM ONTARIO INTO THE
CENTRAL/EASTERN LAKES REGION.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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Area Forecast Discussion
National Weather Service Lincoln IL
1036 AM CST Sat Feb 22 2014
.DISCUSSION...
ISSUED 1035 AM CST Sat Feb 22 2014
Extensive band of altocumulus showing up on regional radar
mosaics, from along the Iowa/Missouri border east to near
Danville. Nothing is reaching the ground yet, as there are still
pretty good temperature/dew point spreads in this corridor.
However, main concern will be with increase in isentropic lift
through the afternoon, as frontogenesis takes place across
southern Missouri into southeast Illinois. While the NAM keeps
things dry through the afternoon, the higher resolution models
such as the RAP, HRRR and Hi-Res-NMM show development of light
precipitation in a couple areas, one north of I-74 and the other
from about Danville southwest through Springfield. The GFS has
been significant more robust with this, indicating around 1/3 inch
of precipitation while the other models are more in the order of a
tenth inch or so depending on mesoscale features. Some of the
lower levels on forecast soundings are rather dry, which could
hold off the precip a bit but also cool the column more quickly to
support a changeover to snow. Have increased PoP`s to around
40-50% east of the Illinois River and north of I-70 for this
afternoon and will need to monitor trends closely for
precipitation type.
Geelhart
&&
.AVIATION...
ISSUED 548 AM CST Sat Feb 22 2014
VFR conditions will prevail at all TAF sites at beginning and
through the morning hours. However, a frontal system will drop
into the area and as the forcing along this front increases during
the afternoon, precipitation will begin to develop over the area.
PIA and BMI will should be a little colder so their pcpn will
begin as a mix of rain and snow. SPI/DEC/CMI should see pcpn begin
as rain, given that their temps should be warmer. As the pcpn
begins, the cigs should drop into the MVFR category around
2.5-3KFT. As the front drops further south, the pcpn at PIA and
BMI will change to just all snow, while the pcpn at SPI/DEC/CMI
will change to a mix of rain and snow. Visibilities will decrease
as well, but only looking at around 5sm right now. Cigs will also
decrease little more, but still remain in the MVFR category. The
pcpn should end during the evening hours at PIA and BMI, and after
midnight at SPI/DEC/CMI. When pcpn ends, clouds should scatter out
for the remainder of the night. Winds will be light and variable
as the front moves through, then become northerly to north-
northeast for the remainder of the TAF period. Wind speeds once
the front passes will increase to around 10-12kts.
Auten
&&
.PREV DISCUSSION...
ISSUED 215 AM CST Sat Feb 22 2014
Weak shortwave that pushed across the area late last evening
produced a few sprinkles over parts of central and east central
Illinois. That wave has shifted off to our east early this morning
with skies clearing from northwest to southeast. However, another
disturbance seen on the water vapor loop over the northern Rockies
with clouds on the increase over parts of western Iowa. At the surface,
a frontal boundary stretched from northern Illinois west through west
central Iowa. This feature is expected to push across our area today
into this evening bringing the threat for some light precipitation.
SHORT TERM...Today through Monday
Main forecast concerns this period were with the upstream shortwave
and its affect on the forecast area with respect to timing and
coverage of precip later this morning or early this afternoon, and
then with precip type issues for tonight.
Deep trof that brought the active weather to our area on Thursday
as north of Lake Superior early this morning with a broad cyclonic
flow prevalent at 500 mb over the Great Lakes. Models coming in line
with respect to the shortwave to our northwest this morning and the
placement of the frontal boundary currently to our northwest. The front
should slide southeast into the area today as the upper wave approaches
from the northwest, setting up a period of light overrunning precip
to the north of the boundary, especially for this afternoon into tonight.
Models have trended a bit more aggressive with the 700-500 mb forcing
for this time period and have thrown out a bit more QPF across the area
as well. Not really sure where this is all coming from as the deeper
moisture has been displaced well off to our east and southeast. However,
as the shortwave drops southeast into the mean longwave trof position,
we should see a bit of amplification with the upper system resulting
in better low and mid level forcing, which may be able to squeeze
out a tenth to two tenths of an inch of QPF.
Forecast soundings off the NAM-WRF suggest a rain snow mix possible
in the north, with soundings too warm to support anything but light
rain this afternoon over the central thru east central areas. As the
frontal boundary slides south of our area by this evening, colder air
will be able to work into the lower levels of the atmosphere which
should change any mix over to light snow from northwest to southeast.
May see around an inch of wet snow over parts of east central Illinois
by later tonight with most of the remainder of the area seeing less
than an inch.
The better 700-500 mb QG forcing and precip threat shifts off to our
east by Sunday morning with another Arctic high situated up across
west central Canada bringing in one of several shots of cold air to
the region over the next week. Today will be the last of the "mild"
days as the colder air moves in starting tonight with temperatures
cooling a few degrees each day heading into Monday. By Monday, another
fast moving shortwave in the northwest flow aloft will approach the
area by evening bringing an increasing chance for light snow to mainly
the north half of the forecast area Monday night, followed by a
reinforcing surge of Arctic air into the middle of next week.
LONG TERM...Tuesday through Friday
Most of the medium range models were on board with the idea of a
another negative height anomaly settling south to near James Bay by
the second half of this forecast period. This should keep our
temperatures well below normal through the period with the main
storm track displaced over the southern Plains eastward through the
Gulf states. Our weather will be coming from the northwest thru most
of this period as shortwaves rotate south and southeast around the
large vortex at 500 mb bringing reinforcing shots of cold air and
chances for light snow or flurries. This far out, timing and magnitude
of these fast moving waves embedded in the northwest flow will be
difficult to forecast so will keep the extended dry for now.
Smith
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
423 PM EST SAT FEB 22 2014
.SYNOPSIS...
ISSUED AT 1230 PM EST SAT FEB 22 2014
DRY CONDITIONS WILL PERSIST THROUGH MID AFTERNOON BUT A COLD
FRONT WILL APPROACH THE REGION LATER TODAY WITH ANOTHER CHANCE OF
SNOWFALL OVERNIGHT...ESPECIALLY NEAR AND SOUTH OF HIGHWAY 24.
PRECIPITATION MAY BEGIN BRIEFLY AS LIGHT RAIN LATE THIS AFTERNOON
BEFORE QUICKLY CHANGING OVER TO ALL SNOW EARLY THIS EVENING AS
COOLER AIR FILTERS IN. IT WILL LIKELY REMAIN DRY TONIGHT OVER
EXTREME NORTHERN INDIANA AND SOUTHWEST LOWER MICHIGAN. CANADIAN
HIGH PRESSURE WILL BRING COOL AND DRY CONDITIONS ON SUNDAY.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 421 PM EST SAT FEB 22 2014
MODELS CONTINUE TO SHOW STRONG SIGNAL FOR NARROW...SHORT DURATION
MESOSCALE SNOW THIS EVENING INTO THE OVERNIGHT HOURS. RELIED HEAVILY
ON HIRES GUIDANCE GIVEN SMALL SCALE NATURE TO THIS EVENT. PREVIOUS
SHIFT LOCKED ONTO EVENT AND ADJUSTMENTS MADE BASED ON LATEST
HRRR...RAP13 AND 12Z ARW EAST AND ARW NMM. RESULT IS A LITTLE
NORTHWARD ADJUST TO POPS AND SNOW BUT NOT BY MUCH. THE HIGHWAY 24
CORRIDOR AND SOUTH STILL APPEAR IN LINE FOR A GENERAL 1 TO 3 WITH
SMALL EMBEDDED AREA OF 2 TO 5 WITH ANY MESOBANDING THAT SETS UP.
STRONG MID LEVEL FORCING DEPICTED WITH OMEGA FIELDS IN THE 15 TO 20
UBAR/S RANGE. FGEN FORCING STILL IMPRESSIVE IN THIS SAME AREA WITH
MESOBANDING POTENTIAL SEEN ON VERTICAL CROSS SECTIONS. HIRES
GUIDANCE HAS BEEN PICKING UP ON THIS WITH SOME IMPRESSIVE LIFT AND
QPF AMOUNTS THIS EVENING BETWEEN ONE QUARTER AND ONE HALF INCH NEAR
AND SOUTH OF HIGHWAY 24. INITIAL CONCERNS WITH DRIER LOW LEVEL AIR
AND MOISTURE GOING INTO SATURATION CONTINUE. LITTLE PCPN HAS BEEN NOTED
THROUGH 19Z UPSTREAM WHERE SOME OF THE HIRES GUIDANCE HAS BEEN
SHOWING UP TO A TENTH OF AN INCH LIQUID ALREADY. RADAR MOSAIC HAS
SHOWN MID LEVEL RETURNS BUT FEW IF ANY SURFACE REPORTS. SATELLITE
SHOWS COOLING CLOUD TOPS AND A SHORT WAVE APPROACHING. COUPLED JET
STREAKS EXPECTED OVER AREA BY 00Z AND AS THESE FEATURES COME
TOGETHER EXPECT PCPN TO BEGIN SATURATING AND REACHING GROUND.
HAVE LEANED AWAY FROM THE HIGHER END QPF GIVEN POOR EARLY
PERFORMANCE UPSTREAM AND FOCUSED MORE ON A BLEND OF THE MID RANGE
VALUES. 16Z HRRR DEPICTION OF SNOW DEVELOPING FROM NEAR KLAF TO KFWA
BY 23Z REASONABLE AND SIMILAR TO LATEST RAP13. BRIEF PERIOD OF RAIN
AT ONSET POSSIBLE WITH LOW LEVEL THERMAL FIELDS ABOVE FREEZING.
HOWEVER...EVAPORATIVE COOLING EXPECTED TO QUICKLY COOL VERY SHALLOW
WARM LAYER AND QUICKLY TRANSITION TO ALL SNOW. DISCUSSION WITH WPC
AGREED WITH A GENERAL 1 TO 2 INCHES AND SMALLER AREA OF 2 TO 4
POSSIBLE WITH EXACT LOCATION REMAINING A BIT UNCERTAIN GIVEN SMALL
SCALE BUT INTENSE FORCING. WOULD NOT RULE OUT A FEW 5 INCH REPORTS
BUT WOULD EXPECT THIS TO BE VERY ISOLATED IN A NARROW BAND. TIMING
SUGGEST HEAVIEST SNOW BETWEEN ABOUT 00Z AND 05Z WITH QUICK ENDING
FROM WEST TO EAST. EXPECT A RATHER SHARP GRADIENT ON NORTHERN
PERIPHERY OF SNOW AND THIS WILL LIKELY NEED SOME ADJUSTMENT THIS
EVENING ONCE SNOW DEVELOPS AND TRENDS ASSESSED.
DRIER AND COOLER AIR MOVES IN LATE TONIGHT AND FOR SUNDAY.
&&
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 421 PM EST SAT FEB 22 2014
A DOMINANT UPSTREAM RIDGE WILL NOT START TO BREAK DOWN UNTIL LATE
THIS WEEK ALLOWING FOR A VERY COLD UPCOMING PERIOD WITH FLOW COMING
FROM THE CANADIAN INTERIOR. OVERALL...THE GFS AND ECMWF WERE
STRUGGLING WITH RUN TO RUN CONSISTENCY IN HANDLING THE TIMING AND
EXTEND OF SUCCESSIVE SURGES OF ARCTIC AIR...ESPECIALLY LATE THIS
UPCOMING WEEK. HOWEVER...THE CANADIAN GEM AND ITS ENSEMBLES HAVE
KEPT A VERY CONSISTENT SIGNAL FOR THE PAST SEVERAL RUNS HANDLING THE
COLD AIR WITH THE ENSEMBLE MEDIAN STAYING 20 TO 25 DEGREES BELOW
NORMAL FROM TUESDAY THROUGH SUNDAY. FOR THIS PACKAGE...GIVEN THIS
VARIABILITY AMONG THE ECMWF AND GFS...BUT STRONG SIGNAL FROM THE
CANADIAN GEM AND ANALOGS...KEPT TEMPERATURES COLD WITH VIRTUALLY NO
CHANGES FROM THE PREVIOUS FORECAST FOR WEDNESDAY THROUGH THE END OF
THE WEEK. THE ECMWF WAS COLDER AGAIN WITH THE 12Z RUN...WITH 850 MB
TEMPS NEAR -27C SATURDAY. GIVEN THE CLIMATOLOGICAL EXTREMES OF THESE
TEMPERATURES...KEPT HIGHS MAINLY IN THE TEENS WEDNESDAY THROUGH
SATURDAY WITH LOWS IN THE SINGLE DIGITS ABOVE ZERO...TO A LITTLE
BELOW ZERO THURSDAY NIGHT. THESE HIGHS AND LOWS ARE WELL IN LINE
WITH THE LATEST CANADIAN GEM/EPS GRAMS. OTHERWISE...KEPT THE
FORECAST DRY EXCEPT FOR A CHANCE FOR SNOW MONDAY NIGHT WITH THE
ARRIVAL OF A WEAK UPPER LEVEL TROF. THE ECMWF...ALTHOUGH STRUGGLING
LATE IN THE FORECAST PERIOD...HAS A GOOD HANDLE ON A WEAK UPSTREAM
SHORTWAVE THAT SHOULD ARRIVE MONDAY NIGHT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1227 PM EST SAT FEB 22 2014
A NARROW BUT INTENSE BAND OF SNOW IS EXPECTED TO DEVELOP THIS
EVENING WITH KFWA SITTING NEAR THE NORTHERN FRINGE OF HEAVIEST
SNOW BAND. KSBN EXPECTED TO REMAIN VFR WITH MID CLOUDS AT TIMES
AND DRY CONDITIONS. SUBTLE WIND SHIFT TO WNW EXPECTED EARLY THIS
EVENING. FURTHER SOUTH...AN INTENSE MESOSCALE BAND OF SNOW IS
BEING DEPICTED TO DEVELOP BY MOST MODELS WITH SOME INTENSE RATES
POSSIBLE FOR A BRIEF PERIOD. THIS BAND ONLY EXPECTED TO BE BETWEEN
50 AND 80 MILES WIDE AND MODELS SHOWING KFWA ANYWHERE FROM CENTER
OF BAND TO JUST ON THE NORTHERN FRINGE. SATELLITE CURRENTLY SHOWS
COOLING CLOUD TOPS UPSTREAM ACROSS NORTHERN MO AND SOUTHERN IL
WHILE RADAR MOSAIC SHOWING MID LEVEL RETURNS DEVELOPING AS FAR
EAST AS WESTERN INDIANA. CONTINUED WITH MVFR VIS AND CIGS IN
LIGHT SNOW AT 23Z AT KFWA BUT ADDED AN IFR COMPONENT GIVEN DECENT
MODEL AGREEMENT ON A PERIOD OF STRONG LIFT ACROSS SOUTHERN ALLEN
COUNTY. LOWER VIS CERTAINLY POSSIBLE FOR A FEW HOURS BUT 00Z TAFS
CAN SHOW THAT BASED ON DEVELOPING RADAR TRENDS AT THAT TIME. PCPN
QUICKLY SHIFTS SOUTH AFTER 05Z WITH DRYING TOWARD DAYBREAK AND VFR
CONDITIONS SUNDAY.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SYNOPSIS...AGD
SHORT TERM...LASHLEY
LONG TERM...SKIPPER
AVIATION...LASHLEY
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
657 PM EST SUN FEB 23 2014
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 435 PM EST SUN FEB 23 2014
THE UPPER GREAT LAKES REGION IS UNDER THE INFLUENCE OF A UPPER
LOW SPINNING OVER EASTERN ONTARIO AT THIS TIME. THIS UPPER LOW HAS
BEEN ROTATING MID LEVEL MOISTURE SOUTHEAST ACROSS THE REGION TODAY
AS SEEN IN WATER VAPOR IMAGERY AND REPRESENTED ON THE 12Z KINL
SOUNDING. WITH THE OPEN WATER OVER PORTIONS OF WESTERN LAKE
SUPERIOR...MOISTURE FROM THE UPPER LOW...AND RAP ANALYZED 850MB
TEMPS AROUND -22C...HAVE BEEN SEEING LAKE CLOUDS AND LIGHT SNOW
SHOWERS ON WEBCAMS AND SATELLITE OVER NORTHERN ONTONAGON...HOUGHTON
AND KEWEENAW COUNTIES. THERE WAS ONE STRONGER BAND THAT STRETCHED
FROM NORTHERN HOUGHTON COUNTY TO JUST NORTH OF GRAND MARAIS. WHERE
THE RADAR CAN SAMPLE IT IT WAS INDICATING SNOWFALL RATES AROUND
0.5-1 INCH AN HOUR SOUTH EAST OF STANNARD ROCK WHERE IT HAS BEEN
AIDED BY ANOTHER AREA OF OPEN WATER. AS WINDS HAVE BEEN SLOWLY
SHIFTING TO THE NORTHWEST...THIS BAND HAS BEEN SHIFTING SOUTH
THROUGH THE DAY...BUT DID GET A REPORT FROM WHITEFISH POINT OF AN
ESTIMATED 6-8 INCHES OF SNOW. WOULD EXPECT AMOUNTS THAT HIGH IN
NORTHERN LUCE COUNTY WITH THE MOVEMENT BUT THINK AMOUNTS IN THE 1-3
INCH RANGE ARE REASONABLE SINCE THIS MORNING.
AS THE UPPER TROUGH AND SURFACE LOW SHIFT EAST TONIGHT...IT WILL
SWEEP A WEAK SHORTWAVE AND SFC-850MB TROUGH SOUTHEAST ACROSS LAKE
SUPERIOR. THESE TROUGHS WILL ACT TO PROVIDE MORE LOW LEVEL MOISTURE
OVER THE REGION TONIGHT INTO MONDAY MORNING AND TURN THE LOW LEVEL
WINDS TO THE NORTHWEST. 850MB TEMPS OF -23C WILL LEAD TO PLENTY OF
OVER THE LAKE INSTABILITY WHERE THERE IS OPEN WATER (INVERSION
HEIGHTS TO 6-7KFT). THERE IS A LITTLE BIT OF AN UNCERTAINTY ON
THE ICE COVERAGE...BUT BASED OFF YESTERDAY/S MODIS IMAGE AND
LOCATION OF LAKE CLOUDS TODAY...IT APPEARS THERE IS DECENT OPEN
WATER FROM TWO HARBORS MINNESOTA TO ISLE ROYALE...THEN
EAST-NORTHEAST OF ISLE ROYALE TO NORTHERN LAKE SUPERIOR AND ALSO TO
THE EAST OF THE KEWEENAW AND TOWARDS MARQUETTE. WHERE ICE CAN BE
MADE OUT...THERE HAS BEEN DECENT MOVEMENT WITH THE WEST-NORTHWEST
WINDS OF 20-30KTS. WITH WEAKENING WINDS INCREASING THE RESIDENCE
TIME OVER THE 20-30MI AREA OF OPEN WATER OVER THE WEST
TONIGHT...THINK THAT WILL BE ENOUGH FOR LIGHT AND OCCASIONALLY
MODERATE LAKE EFFECT SNOWS TO OCCUR FROM CALUMET SOUTHWEST TO
IRONWOOD AND WILL CONTINUE TO SHOW LIKELY AND LOW DEFINITE POPS
FOR THOSE AREAS TONIGHT. NORTH OF CALUMET IS A LITTLE UNCERTAIN ONCE
WINDS TURN TO THE NORTHWEST DUE TO MORE ICE BETWEEN ISLE ROYALE AND
THUNDER BAY AND SMALLER GAPS IN THE FIRST 10-15MI SOUTHEAST FROM
ISLE ROYALE. THEREFORE...WILL HAVE THE POPS LOWER INTO THE LOW END
LIKELY CATEGORY ONCE THE WINDS TURN TO THE NORTHWEST.
OVERALL...SNOWFALL AMOUNTS SHOULD BE LIGHT AND IN THE 1-4 INCH
RANGE. GUSTY THIS EVENING (TO 35MPH)...BUT WITH THE LOW WEAKENING
AND SHIFTING EAST TONIGHT...SHOULD SEE A GRADUAL DIMINISHING TREND
TO THE WINDS. THIS WILL LEADING TO IMPROVING VISIBILITIES FROM THE
BLOWING SNOW OVER THE KEWEENAW PENINSULA. SINCE WE ARE STILL
GETTING REPORTS FROM OBS/WEBCAMS/SPOTTERS OF VISIBILITIES BELOW
1/2MI AT TIMES...DECIDED TO EXTEND THE ADVISORY UNTIL MIDNIGHT.
THIS WILL COVER THE EVENING TRAVEL PERIOD BEFORE THE WINDS DIMINISH
OVERNIGHT.
FARTHER EAST...THE MAIN AREA OF CONCERN WILL BE OVER NORTHERN
LUCE AND THEN TRANSITIONING INTO ALGER COUNTY DUE TO THE FAVORABLE
FETCH ACROSS THE OPEN WATER THAT LIKELY COVERS A DECENT PORTION OF
LSZ265. WITH NORTHWEST WINDS AND PROBABLY SOME LAND BREEZE
INFLUENCE...WOULD THINK THERE WOULD BE SOME ENHANCED LAKE EFFECT
BAND AFFECTING THE COUNTY AND GRADUALLY TRANSITIONED THE BAND
SOUTHWEST THIS EVENING TO AROUND AND JUST EAST OF MUNISING AREA
OVERNIGHT. WITH A POTENTIAL FETCH OF 80MI AND SOME UPSTREAM
MOISTENING OVER THE WESTERN LAKE...WOULDN/T BE SURPRISED IF THERE
ARE SOME LOCALIZED 4 INCH AMOUNTS ESPECIALLY IF THE BAND STALLS IN
AN AREA FOR A FEW HOURS. EAST OF THERE...THE AMOUNT OF ICE COVERAGE
WILL LIKELY LIMIT AMOUNTS AND ONLY HAVE VALUES IN THE 1 TO MAYBE 2
INCH RANGE.
WILL START TO SEE THE AFFECT OF RIDGING UPSTREAM THROUGH THE DAY
TOMORROW AS THE UPPER LOW SHIFTS EAST. THIS WILL LEAD TO INCREASING
850MB TEMPERATURES (ALONG WITH SOME DRYING AND BACKING WINDS) FROM
WEST TO EAST...ESPECIALLY IN THE AFTERNOON. THUS...WILL FOLLOW THAT
TREND FOR POPS AND SNOWFALL AMOUNTS THROUGH THE DAY. HIGHS TOMORROW
WILL BE IN THE LOW-MID TEENS OVER MUCH OF THE AREA. THIS LOOKS TO
BE THE WARMEST HIGHS FOR THE REST OF THE WORK WEEK.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 435 PM EST SUN FEB 23 2014
THE CWA WILL BE DOMINATED BY LOW WIND CHILLS...AND LIGHT TO MODERATE
LES FOR AREAS DOWNWIND OF W TO NW FLOW OVER GAPS IN THE CONSIDERABLE
LAKE ICE COVER.
MON NIGHT...THE STRONGEST 850-500 MB QVECTOR CONV AND
LOWER LEVEL WAA/ISENTROPIC LIFT ASSOCIATED WITH THE FIRST IN A SERIES
OF SHORTWAVE TROUGHS IS EXPECTED TO REMAIN WELL TO THE SOUTH THROUGH
IA INTO SRN WI AND NRN IL. WRLY FLOW LES BANDS WILL SHIFT SLIGHTLY AS
WINDS VEER TO WNW BEHIND A WEAK SFC TROUGH. WITH CONTINUED
UNCERTAINTY ON THE EXTENT OF OPEN WATER AND INVERSION HEIGHTS ONLY
AROUND 5K FT...MENTIONED LIKELY POPS BUT WITH FCST SNOWFALL AMOUNTS
ONLY OF AROUND AN INCH OR TWO.
TUE INTO TUE NIGHT...THE MODELS SUGGEST ANOTHER SHRTWV WITH AN ARCTIC
FRONT BRINGING IN EVEN COLDER AIR WILL MOVE THROUGH BY LATE TUE INTO
TUE NIGHT. WINDS WILL VEER TO THE NW PUSHING THE LIGHT LES OVER A
GRATER PORTION OF THE ERN CWA. WITH MIN TEMPS DROPPING INTO THE -4F
TO -14F RANGE...WIND CHILLS SHOULD ALSO FALL INTO THE -20 TO -30
RANGE.
WED-FRI...A STRONGER SHRTWV WILL MOVE THROUGH THE NRN LAKES AS THE
POLAR TROUGH MOVES INTO NRN ONTARIO. WINDS ARE EXPECTED TO VEER TO
THE NW TO NNW BEHIND THIS FEATURE AS 850 MB TEMPS DROP TO AROUND
-31C THU. WITH THE STRONGER NW WINDS...THE LOWEST WIND CHILLS ARE
EXPECTED THU MORNING INTO THE -25 TO -35 RANGE EVEN THOUGH THERE MAY
SOME MODIFICATION OVER THE MOSTLY FROZEN LAKE. WITH LIGHTER WINDS
AND FEW CLOUDS BY FRI AS THE ARCTIC HIGH SETTLES OVER THE
AREA...TEMPS SHOULD DROP AT LEAST INTO THE -15 TO -25 RANGE OVER
MUCH OF THE CWA...WITH SOME -30S EVEN POSSIBLE FOR TRADITIONAL COLD
SPOTS.
SAT-SUN...THERE IS GREATER UNCERTAINTY WITH ANY INDIVIDUAL SHRTWVS
BUT WITH THE POLAR TROUGH LINGERING NEAR JAMES BAY...ANOTHER BOUT OF
LOWER 850 MB TEMPS AND HIGHER WINDS MAY MOVE IN BY SAT WITH
DIMINISHING WINDS AND CONTINUED COLD ON SUN WITH THE ARCTIC RIDGE
DOMINATING THE NRN LAKES. BY THE WEEKEND...THE ICE COVER IS LIKELY
TO SOLIDIFY...REDUCING LES CHANCES/AMOUNTS.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 656 PM EST SUN FEB 23 2014
WITH WINDS VEERING MORE TO THE NW AND DIMINISHING...EXPECT SOME
IMPROVEMENT AT KCMX AS BLSN DIMINISHES. ALSO...AS ICE FREE OVERWATER
FETCH DECREASES...LAKE EFFECT -SHSN WILL DIMINISH. WHILE THERE MAY
BE A FEW PERIODS OF LIFR VIS THIS EVENING...IFR CONDITIONS SHOULD
GENERALLY PREVAIL THRU THIS FCST PERIOD. HOWEVER...CERTAINLY NOT OUT
OF THE QUESTION THAT CONDITIONS WILL IMPROVE TO PREVAILING MVFR WITH
TIME.
AT KIWD...AS WINDS VEER MORE TO THE NW...EXPECT LAKE EFFECT -SHSN TO
DEVELOP THIS EVENING...EVENTUALLY LEADING TO PREVAILING IFR VIS.
SHOULD SEE IMPROVEMENT BACK TO MVFR MON MORNING AS DEEPER MOISTURE
EXITS. VFR MAY DEVELOP IN THE AFTN.
AT KSAW...DOWNSLOPE NATURE OF THE W TO NW FLOW MAY WORK TO KEEP
CONDITIONS VFR. HOWEVER...WITH INCREASE IN MOISTURE...HIGH MVFR CIGS
SHOULD DEVELOP TONIGHT...THEN LIFT TO VFR MON AFTN.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 435 PM EST SUN FEB 23 2014
THE WEAKENING LOW NEAR HUDSON BAY WILL COMBINE WITH A HIGH PRESSURE
RIDGE MOVING THROUGH THE NORTHERN PLAINS AND MID MISSISSIPPI VALLEY
TO LEAD TO GRADUALLY DECREASING WEST TO NORTHWEST WINDS OVER LAKE
SUPERIOR TONIGHT THROUGH MONDAY NIGHT. HAVE BEEN SEEING THE GALES
PERSISTING OVER THE EASTERN PART OF LAKE SUPERIOR ON THE STANNARD
ROCK AND GRANITE ISLAND OBS THIS AFTERNOON...BUT WITH UPSTREAM OBS
GENERALLY IN THE 30KT RANGE...WOULD EXPECT THE EASTERN SITES TO
COME DOWN SHORTLY. THUS...WILL ALLOW THE GALE WARNING OVER THE
EASTERN LAKE TO EXPIRE AT 00Z AND HAVE ALREADY CANCELLED THE
WESTERN LAKE. EVEN WITH THIS DIMINISHMENT...THERE WILL LIKELY BE
ENOUGH OF A GRADIENT TO KEEP WINDS IN THE 15 TO 30KT RANGE FOR MUCH
OF THE FORECAST PERIOD.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER WEATHER ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR MIZ001-
003.
LAKE SUPERIOR...
GALE WARNING UNTIL 7 PM EST THIS EVENING FOR LSZ265>267.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...JLB
AVIATION...ROLFSON
MARINE...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
411 PM EST SAT FEB 22 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 410 PM EST SAT FEB 22 2014
THE LOW THAT BROUGHT THE SNOW AND MIXED PRECIPITATION TO THE AREA
THURSDAY EVENING INTO FRIDAY HAS BECOME STATIONARY NEAR CAPE
HENRIETTA MARIA BETWEEN HUDSON BAY AND JAMES BAY. THIS NEARLY
STATIONARY LOW WILL COMBINE WITH A 1028MB HIGH PRESSURE RIDGE
SLIDING SOUTHEAST FROM A HIGH IN THE CANADIAN ROCKIES AND INTO THE
NORTHERN PLAINS AND MID MISSISSIPPI VALLEY TO CREATE A TIGHT
PRESSURE GRADIENT OVER THE UPPER GREAT LAKES THROUGH TONIGHT AND
PART OF SUNDAY. THUS...THE WINDS AND RESULTING BLOWING SNOW (MAINLY
OVER THE KEWEENAW) WILL BE THE PRIMARY CONCERN FOR TONIGHT INTO
SUNDAY.
WITH THIS TIGHT PRESSURE GRADIENT REMAINING IN PLACE FOR MUCH OF
THE NIGHT AND COLDER AIR ALOFT SPILLING INTO THE REGION...WOULD
EXPECT THE GUSTY CONDITIONS TO REMAIN THROUGH AT LEAST THE FIRST
HALF OF THE NIGHT. EVEN OVER THE LAST COUPLE OF HOURS...WINDS AT
KCMX HAVE FALLEN TO ONLY 35-40MPH. UPSTREAM AT ISLE ROYALE...WINDS
ARE STILL GUSTING TO SIMILAR VALUES AND WITH MODELS SHOWING GUSTS
TO 35KTS THROUGH BETWEEN 06-12Z...WILL FOLLOW THAT IDEA FOR THE
KEWEENAW TONIGHT. SINCE MUCH OF THE SNOW HAS DIMINISHED AT
KCMX...SEEING MORE OF A SPOTTY NATURE TO THE WORST VISIBILITIES ON
WEBCAMS AND THE KCMX OBS. THUS...THINKING THAT THE GOING ENDING
TIME FOR THE BLIZZARD WARNING IS REASONABLE AND THE EVENING SHIFT
WILL BE ABLE TO LET IT EXPIRE. THE QUESTION IS WHETHER A ADVISORY
WILL BE NEEDED TO COVER THE LINGERING BLOWING/DRIFTING SNOW OR IF
IT COULD BE COVERED BY AN SPS. ALMOST LEANING TOWARDS AN SPS...BUT
WILL ALLOW EVENING SHIFT TO SEE HOW VISIBILITIES ARE DOING OVER THE
NEXT FEW HOURS AND THEN DECIDE. WITH THE CLEARING SKIES AND LITTLE
VSBY RESTRICTIONS ON WEBCAMS IN GOGEBIC/ONTONAGON COUNTIES...HAVE
CANCELLED THE EXISTING WINTER WX ADVISORY FOR THERE.
OVER THE REST OF THE AREA...A SHORTWAVE THAT WAS OVER WESTERN
ONTARIO THIS MORNING HAS SHIFTED EAST-SOUTHEAST AND IS MOVING
ACROSS FAR NORTHERN LAKE SUPERIOR. WITH THIS TRACK...IT LOOKS LIKE
THE DEEPER MOISTURE WILL HOLD OFF MOVING SOUTH OVER THE CWA UNTIL
LATE TONIGHT AND ESPECIALLY INTO SUNDAY AFTERNOON. THUS...THINK
MUCH OF THE CLOUDS AND SNOW CHANCES FOR MUCH OF THE SHORT TERM
PERIOD WILL DEPEND ON LAKE EFFECT. WITH RAP ANALYZED 850MB TEMPS
AROUND -17C AND MODELS SHOWING THAT FALLING TO -23C BY 00Z
MONDAY...THERE IS PLENTY OF OVER LAKE INSTABILITY IF WATER IS
PRESENT ON LAKE SUPERIOR. TODAY/S MODIS IMAGE SHOWS SOME OPEN WATER
THAT HAS DEVELOPED OFF THE ARROWHEAD OF MINNESOTA AND ALSO TO THE
EAST OF THE KEWEENAW. THEREFORE...WITH THE WESTERLY 925MB WINDS
EXPECTED TONIGHT...HAVE FOCUSED CLOUD COVER AND SLIGHT TO LOW
CHANCE POPS IN THE AREAS DOWNWIND OF THOSE PATCHES OF OPEN WATER.
THIS MAINLY AFFECTS THE KEWEENAW PENINSULA. WITH WINDS SHIFTING A
LITTLE MORE TO THE NORTHWEST ON SUNDAY AFTERNOON...HAVE SLOWLY
TRANSITIONED POPS TOWARDS THAT DIRECTION. DIDN/T PUT MUCH FOR
SNOWFALL AMOUNTS (ONLY AROUND AN INCH OR SO) INTO THE FORECAST DUE
TO THE STRENGTH OF THE WINDS LIKELY LIMITING FETCH ACROSS THE OPEN
WATER.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 410 PM EST SAT FEB 22 2014
NO MAJOR CHANGES EXPECTED TO THE LONG TERM FORECAST WITH MUCH BELOW
NORMAL TEMPERATURES AND OCCASIONAL LIGHT SNOW CLOSE TO LAKE
SUPERIOR. WITH THE ARCTIC AIRMASS ONCE AGAIN BUILDING ACROSS HUDSON
BAY...THE COLDEST TEMPERATURES STILL LOOK TO BE WED-FRI WITH TEMPS
STRUGGLING TO RISE ABOVE ZERO ONCE AGAIN.
AS FOR THE DETAILS...THE DEEP LOW PRESSURE OVER JAMES BAY WILL
CONTINUE TO FILL SUNDAY NIGHT THEN FINALLY MOVE EAST BY MONDAY IN
RESPONSE TO A UPPER SHORT WAVE ROTATING AROUND THE UPPER LOW AND
THROUGH THE REGION. THIS WILL ALLOW PBL WINDS TO VEER TO THE NW
SUNDAY NIGHT. THIS VEERING OF WIND COMBINED WITH WEAK UPWARD MOTION
ASSOCIATED WITH THE UPPER SHORT WAVE AND DEEPER MOISTURE SHOULD
ALLOW FOR SOME LAKE EFFECT SNOW TO SPREAD A LITTLE FURTHER WEST
PERHAPS TO THE ALGER/MARQUETTE COUNTY BORDER. IN ADDITION...LES
SHOULD INCREASE ACROSS THE ENTIRE AREA NEAR LAKE SUPERIOR BUT THIS
IS HIGHLY DEPENDENT ON THE FLUXES OVER THE SEMI-OPEN AREAS OF LAKE
SUPERIOR. ONE WOULD THINK THAT WITH THE WIND OVER THE PAST FEW DAYS
THAT THE ICE ON THE LAKE HAS BROKEN UP SOME. IN FACT...TODAY/S MODIS
IMAGERY INDICATES THAT SEVERAL LARGER BREAKS HAVE OPENED ACROSS THE
WESTERN LAKE AS WELL AS EAST OF THE KEWEENAW. IN FACT...WOULD NOT BE
SHOCKED TO SEE A LITTLE MINI BAND OF ENHANCED LES JUST EAST OF THE
KEWEENAW ORIENTED INTO FAR WESTERN ALGER COUNTY...ESPECIALLY IF WE
CAN SEE ENHANCED LAKE BREEZE CONVERGENCE AS THE WINDS VEER TO NW.
FOR NOW...WILL RAISE POPS TO 50 PCT ACROSS ALL OF ALGER INTO LUCE
COUNTIES AND RAISE POPS TO CHC CATEGORY IN ERN MQT COUNTY. BEHIND
THIS SHORT WAVE...LIGHT LES WILL CONTINUE IN THE KEWEENAW AND INTO
ALGER/LUCE COUNTIES WITH NORTHWESTERLY CYCLONIC FLOW. ONCE
AGAIN...IT IS STILL UNCLEAR IF FLUXES WILL INCREASE ENOUGH TO
GENERATE LES OFF THE LAKE. AS SUCH...WILL CONTINUE WITH JUST CHANCE
POPS. WINDS BACK TO WNW TUE AHEAD OF A WEAK SFC TROUGH...WHICH
SHOULD ALLOW ANY LES TO SHIFT OFFSHORE EXCEPT FOR THE KEWEENAW.
THE EXTENDED PERIOD...WED-SAT...CONTINUES TO LOOK EXTREMELY COLD.
THE 12Z NWP CONTINUES TO BE IN VERY GOOD AGREEMENT IN SHOWING THE
ARCTIC FRONT MOVING THROUGH THE UPPER GREAT LAKES WED NIGHT INTO THU
MORNING...OPENING THE DOOR FOR ARCTIC AIR TO MOVE ACROSS THE REGION.
MODELS STILL SHOW 850MB TEMPS DROPPING TO -30 TO -34C BY THU EVENING
WHICH WILL CAUSE TEMPS TO STRUGGLE TO RISE ABOVE ZERO DURING THE
DAY. SFC HIGH PRESSURE IS FCST TO QUICKLY BUILD ACROSS THE AREA THU
NIGHT WHICH SHOULD ALLOW FOR EXCELLENT RADIATIVE COOLING...THUS
DROPPING SFC TEMPS TO -20F OR LOWER. IF THE SKIES CLEAR AND WINDS GO
LIGHT...THIS COULD BE ONE OF THOSE SITUATIONS SIMILAR TO EARLY MARCH
2003 WHERE NWS MQT SAW A MIN TEMP OF -31F. FOR NOW...WILL GO WITH
LOWS FRIDAY MORNING -20 TO -25 BELOW. PERHAPS SOME MODERATION IN
TEMPS BY SATURDAY WITH SLIGHT 850MB WARMING...BUT THE WINDS WILL
ALSO BE INCREASING AS THE ARCTIC HIGH STRENGTHENS LEADING TO A
TIGHTENING PRES GRADIENT ACROSS THE AREA. AS SUCH...APPARENT TEMPS
WILL NOT FEEL MUCH DIFFERENT INTO THE WEEKEND. JUST TO NOTE...THE
LATEST CFS /CLIMATE FORECAST SYSTEM/ GUIDANCE SHOWS MUCH OF MARCH
WITH BELOW NORMAL TEMPERATURES...
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1246 PM EST SAT FEB 22 2014
A NEARLY STATIONARY LOW PRESSURE SYSTEM NEAR HUDSON BAY AND A HIGH
PRESSURE RIDGE MOVING INTO THE MID MISSISSIPPI VALLEY WILL CONTINUE
TO PRODUCE BREEZY CONDITIONS AT THE THREE TAF SITES THROUGH THE
PERIOD. EXPECT THE STRONGEST GUSTS AT KCMX...TO 35-40KTS...THROUGH
THIS EVENING AND THEN A SLIGHT DECREASE TONIGHT INTO SUNDAY
MORNING. THIS WILL CONTINUE TO PRODUCE EXTENSIVE BLOWING SNOW AND
VISIBILITIES TO A QUARTER MILE. AS THE WINDS
DIMINISH...VISIBILITIES MAY TRY TO COME UP SLIGHTLY...BUT SHOULD
STILL BE IN THE 1/2SM RANGE. WITH THE WESTERLY WINDS AND SOME GAPS
IN THE ICE OVER WESTERN LAKE SUPERIOR...COULD SEE SOME SNOW SHOWERS
AT KCMX TOO THROUGH THE PERIOD...WHICH WILL ASSIST THE LOWER
VISIBILITIES.
FOR KIWD/KSAW...OCCASIONAL MVFR CONDITIONS ARE EXPECTED THIS
AFTERNOON WITH A SCATTERED/BROKEN CU FIELD BUT EXPECT THAT TO
DIMINISH ONCE DIURNAL HEATING IS LOST. THEN THE WESTERLY WINDS
WON/T BE FAVORABLE FOR LAKE EFFECT AND KEPT CLOUDS SCATTERED.
DEEPER MOISTURE WILL ROTATE INTO THE AREA DURING THE DAY TOMORROW
AND COULD PRODUCE A MORE SOLID MVFR CLOUD DECK.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 410 PM EST SAT FEB 22 2014
A TIGHT PRESSURE GRADIENT BETWEEN A LOW NEAR HUDSON BAY AND A HIGH
PRESSURE RIDGE MOVING INTO THE MID MISSISSIPPI VALLEY WILL CONTINUE
TO PRODUCE WESTERLY GALE FORCE GUSTS TO 35-40KTS TONIGHT. AS THE
LOW WEAKENS ON SUNDAY...THE GRADIENT WILL WEAKEN AND LEAD TO WINDS
DROPPING TO 30KTS. NORTHWESTERLY WINDS WILL CONTINUE SUNDAY NIGHT
INTO THE FIRST HALF OF THE UPCOMING WORK WEEK...WITH GUSTS UP TO
25KTS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
BLIZZARD WARNING UNTIL 7 PM EST THIS EVENING FOR MIZ001-003.
LAKE SUPERIOR...
GALE WARNING UNTIL 7 AM EST /6 AM CST/ SUNDAY FOR LSZ240>246-
263>267.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...MRD
AVIATION...SRF
MARINE...SRF
AREA FORECAST DISCUSSION
NWS DULUTH MN
1216 PM CST SAT FEB 22 2014
.UPDATE...
ISSUED AT 1216 PM CST SAT FEB 22 2014
ADDED A BIT MORE SKY COVER TO THE NORTHERN HALF OF THE FA AS
CLOUDS LEAK ACROSS THE INTERNATIONAL BORDER TO JUST N OF THE IRON
RANGE. CLOUD COVER HAS FORMED ALONG THE N SHORE AND HAVE ADDED.
MADE SOME OTHER MINOR ADJUSTMENTS.
UPDATE ISSUED AT 930 AM CST SAT FEB 22 2014
ADJUSTED SKY COVER DOWNWARD TO ACCOUNT FOR MORE SUNSHINE THAN
CLOUD COVER ATTM. WILL KEEP AN EYE ON THE CLOUDS N OF THE CANADIAN
BORDER AS SOME ARE JUST S OF THE BORDER. ADDED A MENTION OF
FLURRIES ALONG THE N SHORE WHERE TWM AND BFW HAVE REPORTED
FLURRIES. TIGHT PRESSURE GRADIENT OVER THE FA ATTM WILL KEEP GUSTY
WINDS IN PLAY TODAY.
&&
.SYNOPSIS...
ISSUED AT 339 AM CST SAT FEB 22 2014
SFC/MID LVL LOW NEAR HUDSON BAY HAS A VERY LARGE AND DEEP
CIRCULATION THAT EXTENDS ACROSS ALL OF THE CWA. EXTENSIVE CANOPY OF
CLOUD COVER REMAINS OVER THE REGION ALTHOUGH SLOW CLEARING IS
OCCURRING IN SWRN CORNER OF CWA. OCCASIONAL SNOW SHOWERS HAVE
CONTINUED NEAR THE INTERNATIONAL BORDER..AND JUST EAST OF CWA IN
GOGEBIC COUNTY. LATEST DLH VWP SHOWS 28735KT WINDS NEAR 1.5K FT WHICH
AGREES WITH FCST RAP .5KM AGL. MANY LOCATIONS CONTINUE TO HAVE WELL
MIXED BDRY LYR WITH GUSTY WINDS.
&&
.SHORT TERM...(TODAY THROUGH TOMORROW)
ISSUED AT 339 AM CST SAT FEB 22 2014
LARGE CIRCULATION FROM HUDSON BAY LOW WILL CONTINUE TO AFFECT THE
NORTHLAND THROUGH THE PERIOD. GUSTY WINDS SHOULD PREVAIL AS
DEEPLY STACKED LOW KEEPS A HIGHLY KINEMATIC PATTERN IN PLACE.
STATIONARY NATURE OF MID LVL LOW WILL KEEP A CONSIDERABLE AMOUNT
OF CLOUD COVER OVER NRN AND EASTERN CWA. AMOUNT OF CLEARING IS
LOWER CONFIDENCE ASPECT OF FCST AS ANY SIGNIFICANT CLEARING MAY
ALLOW FOR INSTABILITY CU DEVELOPMENT. SNOW SHOWERS OR FLURRIES ARE
POSSIBLE OVER NRN MN ZONES AND ACROSS NW WISCONSIN SAT AFTN. TEMPS
REMAIN WELL BELOW CLIMO THROUGH THE WEEKEND.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 339 AM CST SAT FEB 22 2014
UNSEASONABLY COLD WEATHER IS EXPECTED TO SETTLE INTO THE NORTHLAND
DURING THE EXTENDED TIME PERIOD...AND REMAIN THERE THROUGHOUT THE
PERIOD. HIGH TEMPERATURES WILL BE SOME 10 TO 20 DEGREES BELOW NORMAL
DURING THE PERIOD...WITH OVERNIGHT LOW TEMPERATURES ON THE ORDER OF
15 TO 25 DEGREES BELOW NORMAL AT TIMES. THIS WILL ENSURE WE CLOSE
OUT THIS MONTH WITH A MAJOR DEPARTURE FROM NORMAL. ON SUNDAY NIGHT
AND MONDAY THERE SHOULD BE A BRIEF WARM UP...BUT IT WILL STILL BELOW
NORMAL. A LOW PRESSURE SYSTEM WILL BRING SOME LIGHT SNOW TO THE
REGION. AT THIS POINT...IT IS POINTING TO AREAS JUST SOUTH OF THE
CWA...BUT THE NEW ECMWF JUST CAME IN WITH SOME LIGHT QPF IN OUR CWA.
MAY NEED TO ADD SOME POPS AT SOME POINT FOR THE CWA. BEHIND THIS
DEPARTING WEAK LOW PRESSURE SYSTEM...A MAJOR ARCTIC AIR MASS WILL
SETTLE INTO THE REGION ON A MAJOR TROUGH SETTING IN OVER THE GREAT
LAKES. IN SUMMARY...TEMPERATURES WILL BE WELL BELOW NORMAL WITH
LITTLE TO NO PRECIPITATION THROUGHOUT THE PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1139 AM CST SAT FEB 22 2014
LOW PRESSURE OVER HUDSON BAY WILL CONTINUE TO AFFECT THE NORTHLAND
THROUGH THE NEXT 24 HOURS WITH PERIODS OF CLOUDS AND SNOW SHOWERS
AS WELL AS GUSTY WINDS. THE MINNESOTA ARROWHEAD...KINL/KHIB AND
KDLH...ARE MOST LIKELY TO SEE THE CLOUDS STREAMING DOWN FROM
CANADA AT BKN-OVC020-030. GUSTY WEST TO NORTHWEST WINDS WILL
GRADUALLY DECREASE TO ABOUT 10 KTS AFTER 00Z.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH -2 11 -9 9 / 10 0 0 10
INL -4 8 -11 6 / 10 20 20 10
BRD -6 12 -11 10 / 0 0 10 10
HYR -5 13 -9 11 / 10 10 20 10
ASX 0 14 -4 12 / 10 10 20 10
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
UPDATE...GSF
SYNOPSIS...CANNON
SHORT TERM...CANNON
LONG TERM...DAP
AVIATION...CLC
AREA FORECAST DISCUSSION...UPDATED
NWS DULUTH MN
1143 AM CST SAT FEB 22 2014
.UPDATE...
ISSUED AT 930 AM CST SAT FEB 22 2014
ADJUSTED SKY COVER DOWNWARD TO ACCOUNT FOR MORE SUNSHINE THAN
CLOUD COVER ATTM. WILL KEEP AN EYE ON THE CLOUDS N OF THE CANADIAN
BORDER AS SOME ARE JUST S OF THE BORDER. ADDED A MENTION OF
FLURRIES ALONG THE N SHORE WHERE TWM AND BFW HAVE REPORTED
FLURRIES. TIGHT PRESSURE GRADIENT OVER THE FA ATTM WILL KEEP GUSTY
WINDS IN PLAY TODAY.
&&
.SYNOPSIS...
ISSUED AT 339 AM CST SAT FEB 22 2014
SFC/MID LVL LOW NEAR HUDSON BAY HAS A VERY LARGE AND DEEP
CIRCULATION THAT EXTENDS ACROSS ALL OF THE CWA. EXTENSIVE CANOPY OF
CLOUD COVER REMAINS OVER THE REGION ALTHOUGH SLOW CLEARING IS
OCCURRING IN SWRN CORNER OF CWA. OCCASIONAL SNOW SHOWERS HAVE
CONTINUED NEAR THE INTERNATIONAL BORDER..AND JUST EAST OF CWA IN
GOGEBIC COUNTY. LATEST DLH VWP SHOWS 28735KT WINDS NEAR 1.5K FT WHICH
AGREES WITH FCST RAP .5KM AGL. MANY LOCATIONS CONTINUE TO HAVE WELL
MIXED BDRY LYR WITH GUSTY WINDS.
&&
.SHORT TERM...(TODAY THROUGH TOMORROW)
ISSUED AT 339 AM CST SAT FEB 22 2014
LARGE CIRCULATION FROM HUDSON BAY LOW WILL CONTINUE TO AFFECT THE
NORTHLAND THROUGH THE PERIOD. GUSTY WINDS SHOULD PREVAIL AS
DEEPLY STACKED LOW KEEPS A HIGHLY KINEMATIC PATTERN IN PLACE.
STATIONARY NATURE OF MID LVL LOW WILL KEEP A CONSIDERABLE AMOUNT
OF CLOUD COVER OVER NRN AND EASTERN CWA. AMOUNT OF CLEARING IS
LOWER CONFIDENCE ASPECT OF FCST AS ANY SIGNIFICANT CLEARING MAY
ALLOW FOR INSTABILITY CU DEVELOPMENT. SNOW SHOWERS OR FLURRIES ARE
POSSIBLE OVER NRN MN ZONES AND ACROSS NW WISCONSIN SAT AFTN. TEMPS
REMAIN WELL BELOW CLIMO THROUGH THE WEEKEND.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 339 AM CST SAT FEB 22 2014
UNSEASONABLY COLD WEATHER IS EXPECTED TO SETTLE INTO THE NORTHLAND
DURING THE EXTENDED TIME PERIOD...AND REMAIN THERE THROUGHOUT THE
PERIOD. HIGH TEMPERATURES WILL BE SOME 10 TO 20 DEGREES BELOW NORMAL
DURING THE PERIOD...WITH OVERNIGHT LOW TEMPERATURES ON THE ORDER OF
15 TO 25 DEGREES BELOW NORMAL AT TIMES. THIS WILL ENSURE WE CLOSE
OUT THIS MONTH WITH A MAJOR DEPARTURE FROM NORMAL. ON SUNDAY NIGHT
AND MONDAY THERE SHOULD BE A BRIEF WARM UP...BUT IT WILL STILL BELOW
NORMAL. A LOW PRESSURE SYSTEM WILL BRING SOME LIGHT SNOW TO THE
REGION. AT THIS POINT...IT IS POINTING TO AREAS JUST SOUTH OF THE
CWA...BUT THE NEW ECMWF JUST CAME IN WITH SOME LIGHT QPF IN OUR CWA.
MAY NEED TO ADD SOME POPS AT SOME POINT FOR THE CWA. BEHIND THIS
DEPARTING WEAK LOW PRESSURE SYSTEM...A MAJOR ARCTIC AIR MASS WILL
SETTLE INTO THE REGION ON A MAJOR TROUGH SETTING IN OVER THE GREAT
LAKES. IN SUMMARY...TEMPERATURES WILL BE WELL BELOW NORMAL WITH
LITTLE TO NO PRECIPITATION THROUGHOUT THE PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1139 AM CST SAT FEB 22 2014
LOW PRESSURE OVER HUDSON BAY WILL CONTINUE TO AFFECT THE NORTHLAND
THROUGH THE NEXT 24 HOURS WITH PERIODS OF CLOUDS AND SNOW SHOWERS
AS WELL AS GUSTY WINDS. THE MINNESOTA ARROWHEAD...KINL/KHIB AND
KDLH...ARE MOST LIKELY TO SEE THE CLOUDS STREAMING DOWN FROM
CANADA AT BKN-OVC020-030. GUSTY WEST TO NORTHWEST WINDS WILL
GRADUALLY DECRESE TO ABOUT 10 KTS AFTER 00Z.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 12 -2 11 -9 / 10 10 0 0
INL 10 -4 8 -11 / 20 10 20 20
BRD 13 -6 12 -11 / 10 0 0 10
HYR 15 -5 13 -9 / 10 10 10 20
ASX 15 0 14 -4 / 10 10 10 20
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
UPDATE...GSF
SYNOPSIS...CANNON
SHORT TERM...CANNON
LONG TERM...DAP
AVIATION...CLC
AREA FORECAST DISCUSSION
NWS DULUTH MN
933 AM CST SAT FEB 22 2014
.UPDATE...
ISSUED AT 930 AM CST SAT FEB 22 2014
ADJUSTED SKY COVER DOWNWARD TO ACCOUNT FOR MORE SUNSHINE THAN
CLOUD COVER ATTM. WILL KEEP AN EYE ON THE CLOUDS N OF THE CANADIAN
BORDER AS SOME ARE JUST S OF THE BORDER. ADDED A MENTION OF
FLURRIES ALONG THE N SHORE WHERE TWM AND BFW HAVE REPORTED
FLURRIES. TIGHT PRESSURE GRADIENT OVER THE FA ATTM WILL KEEP GUSTY
WINDS IN PLAY TODAY.
&&
.SYNOPSIS...
ISSUED AT 339 AM CST SAT FEB 22 2014
SFC/MID LVL LOW NEAR HUDSON BAY HAS A VERY LARGE AND DEEP
CIRCULATION THAT EXTENDS ACROSS ALL OF THE CWA. EXTENSIVE CANOPY OF
CLOUD COVER REMAINS OVER THE REGION ALTHOUGH SLOW CLEARING IS
OCCURRING IN SWRN CORNER OF CWA. OCCASIONAL SNOW SHOWERS HAVE
CONTINUED NEAR THE INTERNATIONAL BORDER..AND JUST EAST OF CWA IN
GOGEBIC COUNTY. LATEST DLH VWP SHOWS 28735KT WINDS NEAR 1.5K FT WHICH
AGREES WITH FCST RAP .5KM AGL. MANY LOCATIONS CONTINUE TO HAVE WELL
MIXED BDRY LYR WITH GUSTY WINDS.
&&
.SHORT TERM...(TODAY THROUGH TOMORROW)
ISSUED AT 339 AM CST SAT FEB 22 2014
LARGE CIRCULATION FROM HUDSON BAY LOW WILL CONTINUE TO AFFECT THE
NORTHLAND THROUGH THE PERIOD. GUSTY WINDS SHOULD PREVAIL AS
DEEPLY STACKED LOW KEEPS A HIGHLY KINEMATIC PATTERN IN PLACE.
STATIONARY NATURE OF MID LVL LOW WILL KEEP A CONSIDERABLE AMOUNT
OF CLOUD COVER OVER NRN AND EASTERN CWA. AMOUNT OF CLEARING IS
LOWER CONFIDENCE ASPECT OF FCST AS ANY SIGNIFICANT CLEARING MAY
ALLOW FOR INSTABILITY CU DEVELOPMENT. SNOW SHOWERS OR FLURRIES ARE
POSSIBLE OVER NRN MN ZONES AND ACROSS NW WISCONSIN SAT AFTN. TEMPS
REMAIN WELL BELOW CLIMO THROUGH THE WEEKEND.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 339 AM CST SAT FEB 22 2014
UNSEASONABLY COLD WEATHER IS EXPECTED TO SETTLE INTO THE NORTHLAND
DURING THE EXTENDED TIME PERIOD...AND REMAIN THERE THROUGHOUT THE
PERIOD. HIGH TEMPERATURES WILL BE SOME 10 TO 20 DEGREES BELOW NORMAL
DURING THE PERIOD...WITH OVERNIGHT LOW TEMPERATURES ON THE ORDER OF
15 TO 25 DEGREES BELOW NORMAL AT TIMES. THIS WILL ENSURE WE CLOSE
OUT THIS MONTH WITH A MAJOR DEPARTURE FROM NORMAL. ON SUNDAY NIGHT
AND MONDAY THERE SHOULD BE A BRIEF WARM UP...BUT IT WILL STILL BELOW
NORMAL. A LOW PRESSURE SYSTEM WILL BRING SOME LIGHT SNOW TO THE
REGION. AT THIS POINT...IT IS POINTING TO AREAS JUST SOUTH OF THE
CWA...BUT THE NEW ECMWF JUST CAME IN WITH SOME LIGHT QPF IN OUR CWA.
MAY NEED TO ADD SOME POPS AT SOME POINT FOR THE CWA. BEHIND THIS
DEPARTING WEAK LOW PRESSURE SYSTEM...A MAJOR ARCTIC AIR MASS WILL
SETTLE INTO THE REGION ON A MAJOR TROUGH SETTING IN OVER THE GREAT
LAKES. IN SUMMARY...TEMPERATURES WILL BE WELL BELOW NORMAL WITH
LITTLE TO NO PRECIPITATION THROUGHOUT THE PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 614 AM CST SAT FEB 22 2014
LARGELY VFR CONDITIONS ARE IN STORE FOR THE TAF SITES THROUGHOUT
THE PERIOD...BUT THERE WILL BE AREAS OF MVFR CIGS/VSBYS DUE TO
SCATTERED SNOW SHOWERS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 12 -2 11 -9 / 10 10 0 0
INL 10 -4 8 -11 / 20 10 20 20
BRD 13 -6 12 -11 / 10 0 0 10
HYR 15 -5 13 -9 / 10 10 10 20
ASX 15 0 14 -4 / 10 10 10 20
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
UPDATE...GSF
SYNOPSIS...CANNON
SHORT TERM...CANNON
LONG TERM...DAP
AVIATION...DAP
AREA FORECAST DISCUSSION
NWS DULUTH MN
614 AM CST SAT FEB 22 2014
.UPDATE...
ISSUED AT 614 AM CST SAT FEB 22 2014
UPDATED FOR NEW AVIATION DISCUSSION BELOW.
&&
.SYNOPSIS...
ISSUED AT 339 AM CST SAT FEB 22 2014
SFC/MID LVL LOW NEAR HUDSON BAY HAS A VERY LARGE AND DEEP
CIRCULATION THAT EXTENDS ACROSS ALL OF THE CWA. EXTENSIVE CANOPY OF
CLOUD COVER REMAINS OVER THE REGION ALTHOUGH SLOW CLEARING IS
OCCURRING IN SWRN CORNER OF CWA. OCCASIONAL SNOW SHOWERS HAVE
CONTINUED NEAR THE INTERNATIONAL BORDER..AND JUST EAST OF CWA IN
GOGEBIC COUNTY. LATEST DLHVWP SHOWS 28735KT WINDS NEAR 1.5K FT WHICH
AGREES WITH FCST RAP .5KM AGL. MANY LOCATIONS CONTINUE TO HAVE WELL
MIXED BDRY LYR WITH GUSTY WINDS.
&&
.SHORT TERM...(TODAY THROUGH TOMORROW)
ISSUED AT 339 AM CST SAT FEB 22 2014
LARGE CIRCULATION FROM HUDSON BAY LOW WILL CONTINUE TO AFFECT THE
NORTHLAND THROUGH THE PERIOD. GUSTY WINDS SHOULD PREVAIL AS
DEEPLY STACKED LOW KEEPS A HIGHLY KINEMATIC PATTERN IN PLACE.
STATIONARY NATURE OF MID LVL LOW WILL KEEP A CONSIDERABLE AMOUNT
OF CLOUD COVER OVER NRN AND EASTERN CWA. AMOUNT OF CLEARING IS
LOWER CONFIDENCE ASPECT OF FCST AS ANY SIGNIFICANT CLEARING MAY
ALLOW FOR INSTABILITY CU DEVELOPMENT. SNOW SHOWERS OR FLURRIES ARE
POSSIBLE OVER NRN MN ZONES AND ACROSS NW WISCONSIN SAT AFTN. TEMPS
REMAIN WELL BELOW CLIMO THROUGH THE WEEKEND.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 339 AM CST SAT FEB 22 2014
UNSEASONABLY COLD WEATHER IS EXPECTED TO SETTLE INTO THE NORTHLAND
DURING THE EXTENDED TIME PERIOD...AND REMAIN THERE THROUGHOUT THE
PERIOD. HIGH TEMPERATURES WILL BE SOME 10 TO 20 DEGREES BELOW NORMAL
DURING THE PERIOD...WITH OVERNIGHT LOW TEMPERATURES ON THE ORDER OF
15 TO 25 DEGREES BELOW NORMAL AT TIMES. THIS WILL ENSURE WE CLOSE
OUT THIS MONTH WITH A MAJOR DEPARTURE FROM NORMAL. ON SUNDAY NIGHT
AND MONDAY THERE SHOULD BE A BRIEF WARMUP...BUT IT WILL STILL BELOW
NORMAL. A LOW PRESSURE SYSTEM WILL BRING SOME LIGHT SNOW TO THE
REGION. AT THIS POINT...IT IS POINTING TO AREAS JUST SOUTH OF THE
CWA...BUT THE NEW ECMWF JUST CAME IN WITH SOME LIGHT QPF IN OUR CWA.
MAY NEED TO ADD SOME POPS AT SOME POINT FOR THE CWA. BEHIND THIS
DEPARTING WEAK LOW PRESSURE SYSTEM...A MAJOR ARCTIC AIRMASS WILL
SETTLE INTO THE REGION ON A MAJOR TROUGH SETTING IN OVER THE GREAT
LAKES. IN SUMMARY...TEMPERATURES WILL BE WELL BELOW NORMAL WITH
LITTLE TO NO PRECIPITATION THROUGHOUT THE PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 614 AM CST SAT FEB 22 2014
LARGELY VFR CONDITIONS ARE IN STORE FOR THE TAF SITES THROUGHOUT
THE PERIOD...BUT THERE WILL BE AREAS OF MVFR CIGS/VSBYS DUE TO
SCATTERED SNOW SHOWERS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 12 -2 11 -9 / 10 10 0 0
INL 10 -4 8 -11 / 20 10 20 20
BRD 12 -6 12 -11 / 10 0 0 10
HYR 14 -5 13 -9 / 10 10 10 20
ASX 15 0 14 -4 / 10 10 10 20
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
UPDATE...DAP
SYNOPSIS...CANNON
SHORT TERM...CANNON
LONG TERM...DAP
AVIATION...DAP
AREA FORECAST DISCUSSION
NWS DULUTH MN
352 AM CST SAT FEB 22 2014
.SYNOPSIS...
ISSUED AT 339 AM CST SAT FEB 22 2014
SFC/MID LVL LOW NEAR HUDSON BAY HAS A VERY LARGE AND DEEP
CIRCULATION THAT EXTENDS ACROSS ALL OF THE CWA. EXTENSIVE CANOPY OF
CLOUD COVER REMAINS OVER THE REGION ALTHOUGH SLOW CLEARING IS
OCCURRING IN SWRN CORNER OF CWA. OCCASIONAL SNOW SHOWERS HAVE
CONTINUED NEAR THE INTERNATIONAL BORDER..AND JUST EAST OF CWA IN
GOGEBIC COUNTY. LATEST DLHVWP SHOWS 28735KT WINDS NEAR 1.5K FT WHICH
AGREES WITH FCST RAP .5KM AGL. MANY LOCATIONS CONTINUE TO HAVE WELL
MIXED BDRY LYR WITH GUSTY WINDS.
&&
.SHORT TERM...(TODAY THROUGH TOMORROW)
ISSUED AT 339 AM CST SAT FEB 22 2014
LARGE CIRCULATION FROM HUDSON BAY LOW WILL CONTINUE TO AFFECT THE
NORTHLAND THROUGH THE PERIOD. GUSTY WINDS SHOULD PREVAIL AS
DEEPLY STACKED LOW KEEPS A HIGHLY KINEMATIC PATTERN IN PLACE.
STATIONARY NATURE OF MID LVL LOW WILL KEEP A CONSIDERABLE AMOUNT
OF CLOUD COVER OVER NRN AND EASTERN CWA. AMOUNT OF CLEARING IS
LOWER CONFIDENCE ASPECT OF FCST AS ANY SIGNIFICANT CLEARING MAY
ALLOW FOR INSTABILITY CU DEVELOPMENT. SNOW SHOWERS OR FLURRIES ARE
POSSIBLE OVER NRN MN ZONES AND ACROSS NW WISCONSIN SAT AFTN. TEMPS
REMAIN WELL BELOW CLIMO THROUGH THE WEEKEND.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 339 AM CST SAT FEB 22 2014
UNSEASONABLY COLD WEATHER IS EXPECTED TO SETTLE INTO THE NORTHLAND
DURING THE EXTENDED TIME PERIOD...AND REMAIN THERE THROUGHOUT THE
PERIOD. HIGH TEMPERATURES WILL BE SOME 10 TO 20 DEGREES BELOW NORMAL
DURING THE PERIOD...WITH OVERNIGHT LOW TEMPERATURES ON THE ORDER OF
15 TO 25 DEGREES BELOW NORMAL AT TIMES. THIS WILL ENSURE WE CLOSE
OUT THIS MONTH WITH A MAJOR DEPARTURE FROM NORMAL. ON SUNDAY NIGHT
AND MONDAY THERE SHOULD BE A BRIEF WARMUP...BUT IT WILL STILL BELOW
NORMAL. A LOW PRESSURE SYSTEM WILL BRING SOME LIGHT SNOW TO THE
REGION. AT THIS POINT...IT IS POINTING TO AREAS JUST SOUTH OF THE
CWA...BUT THE NEW ECMWF JUST CAME IN WITH SOME LIGHT QPF IN OUR CWA.
MAY NEED TO ADD SOME POPS AT SOME POINT FOR THE CWA. BEHIND THIS
DEPARTING WEAK LOW PRESSURE SYSTEM...A MAJOR ARCTIC AIRMASS WILL
SETTLE INTO THE REGION ON A MAJOR TROUGH SETTING IN OVER THE GREAT
LAKES. IN SUMMARY...TEMPERATURES WILL BE WELL BELOW NORMAL WITH
LITTLE TO NO PRECIPITATION THROUGHOUT THE PERIOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1240 AM CST SAT FEB 22 2014
LARGELY VFR CONDITIONS ARE IN STORE FOR THE TAF SITES THROUGHOUT
THE TAF PERIOD. AREAS OF MVFR CIGS/VSBYS DUE TO SNOW SHOWERS WILL
BE POSSIBLE THROUGHOUT THE PERIOD...BUT THEY WILL BE HIT OR MISS
AS THE SNOW SHOWERS WILL BE SCATTERED. AS DRIER AIR GRADUALLY
WORKS ITS WAY IN THE MVFR CIGS/VSBYS WILL BECOME LESS COMMON.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 12 -2 11 -9 / 10 10 0 0
INL 10 -4 8 -11 / 20 10 20 20
BRD 12 -6 12 -11 / 10 0 0 10
HYR 14 -5 13 -9 / 10 10 10 20
ASX 15 0 14 -4 / 10 10 10 20
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
SYNOPSIS...CANNON
SHORT TERM...CANNON
LONG TERM...DAP
AVIATION...DAP
AREA FORECAST DISCUSSION
NWS HASTINGS NE
407 PM CST SAT FEB 22 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 407 PM CST SAT FEB 22 2014
...ABOVE NORMAL UNCERTAINTY TONIGHT IN A SWATH OF SNOW THAT COULD
END UP DUMPING 6-8 INCHES "IF" THE WORST CASE UNFOLDS...
ALOFT: VERY LOW AMPLITUDE WNW CYCLONIC FLOW WILL REMAIN OVER THE
CNTRL PLAINS THRU SUN. WV IMAGERY SHOWS A SUBTLE SHORTWAVE TROF
OVER BRITISH COLUMBIA. PART OF THIS TROF WILL RACE THRU TONIGHT.
SURFACE: A COLD FRONT MOVED THRU LAST NIGHT AND CURRENTLY
EXTENDED FROM ST. LOUIS-OKLAHOMA CITY-LUBBOCK TX. THIS FRONT WILL
SLOWLY SAG DEEPER INTO TX/AR BY SUNSET SUNDAY.
MEANWHILE...CANADIAN HIGH PRES WILL GRADUALLY BUILD S THRU THE
PLAINS.
REST OF THIS AFTERNOON: INCREASING CLOUDS OVER S-CNTRL NEB WILL
OBSCURE THE SUN WHILE N-CNTRL KS SHOULD SEE A NICE END TO THE DAY.
HIGH TEMPS WILL OCCUR 4-5 PM.
TONIGHT: BECOMING CLOUDY WITH A BAND OF SNOW DEVELOPING ACROSS
THE FCST AREA AND IT COULD BECOME HEAVY IN A VERY NARROW SWATH
OVER S-CNTRL NEB. PROBABILITIES OF NO SNOW AT ALL ARE HIGHEST OVER
N-CNTRL KS.
THIS WILL BE A JET STREAK DRIVEN EVENT AS WIND/MASS ADJUSTMENTS
RESULT IN WARM AIR ADVECTION AND FRONTOGENESIS /FGEN/ ON THE
FRONT THAT MOVED THRU LAST NIGHT. CROSS SECTIONS INDICATE MID-
LEVEL UPRIGHT INSTABILITY AND LIFT WILL BE STRONG IN THE DENDRITIC
GROWTH ZONE /DGZ/.
SEVERAL SCENARIOS ARE POSSIBLE TONIGHT AND WE WILL REALLY NOT KNOW
WHICH ONE IS RIGHT UNTIL WE SEE THIS UNFOLD. THIS FCST IS FRAUGHT
WITH UNCERTAINTY AND WE ARE ADMITTEDLY CONSERVATIVE ON SNOW
AMOUNTS AND THE AERIAL EXTENT OF THE ADVISORY. BE PREPARED FOR
ADJUSTMENTS LATER THIS EVENING AND TONIGHT THAT COULD RESULT IN
DRAMATICALLY INCREASING OR DECREASING AMOUNTS FOR YOUR AREA.
09Z AND 15Z SREF PROBABILITIES FOR .25" ARE HIGHEST IN THE
ADVISORY AREA. THE 15Z PROBS FOR .25" ARE HIGHER THAN 09Z AND THE
70% CHANCE OF .25" NOW EXTENDS E TO GRI. THE 19Z RAP SUPPORTS
THIS. A CHECK OF THE 18Z NAM HAS .25" TO HASTINGS.
SNOW TOTALS: GENERALLY 1-3" OVER S-CNTRL NEB. 2-3" FROM THE
TRI-CITIES WESTWARD...AND 3-4" PRIMARILY OVER DAWSON COUNTY. THIS
IS OUR BEST STAB USING A BLEND THE 00Z/06Z/12Z MULTI-MODEL QPF.
THAT PRESENTS A PROBLEM. TOO MUCH AVERAGING SHOULD HIT THE SWATH
OF SNOW CORRECTLY...BUT IT MAY BE TOO BROAD COMPARED TO REALITY
AND FCST AMOUNTS MAY NOT BE HIGH ENOUGH.
SNOW-LIQUID RATIOS: USED PRIMARILY 15:1 THRU THE EVENING AND
CLOSE TO 20:1 AFTER MIDNIGHT. GIVEN THE STRENGTH OF THE LIFT IN
THE DGZ... THESE RATIOS COULD ALSO BE CONSERVATIVE.
POSSIBLE WEAKNESSES IN TONIGHT/S FCST:
1) WE MAY BE TOO BROAD WITH THE EDGES OF THE SNOW BAND...I.E. IT
MAY BE MORE NARROW THAN DEPICTED.
2) DO WE HAVE THE HIGHEST POPS IN THE RIGHT LOCATION? THE HI-RES
GEM HAS THE BAND BETWEEN I-80 AND THE KS BORDER. WE ARE IN THE
I-80 CORRIDOR.
3) DEWPOINTS MAY BE TOO HIGH N OF I-80. DEWPOINTS IN THE SINGLE
DIGITS ARE AS CLOSE AS O`NEILL. ADVECTION OF THIS VERY DRY AIR
WILL PLAY A ROLE IN LIMITING THE NRN EXTENT OF THE BAND.
4) ARE AMOUNTS HIGH ENOUGH? WOULD NOT BE SURPRISED TO SEE A
NARROW STRIP OF WARNING LEVEL SNOW /6-8"/ SOMEWHERE GIVEN THE
RATIOS WE ARE LIKELY TO SEE.
UNCERTAINTY: PLEASE KEEP IN MIND THAT THERE ARE SOME AREAS THAT
HAVE SNOW IN THE FCST...BUT WILL SEE NO SNOW AT ALL. THIS
ESPECIALLY APPLIES IF THE FCST PROBABILITY OF SNOW AT YOUR
LOCATION IS 40% OR BELOW. THERE WILL BE A SHARP CUT-OFF ON THE NRN
AND SRN FRINGES OF THIS BAND. THE SMALL SCALE NATURE OF THIS BAND
IS PROBLEMATIC FOR PINNING DOWN DETAILS...BUT THIS COULD END UP A
WARNING LEVEL EVENT FOR SOME COUNTIES.
LOW TEMPS WERE FROM CONSENSUS OF 2M TEMPS WHICH RAISED TEMPS
SEVERAL DEGREES.
SUN: FGEN LIFTS N AND MID-LEVELS DRY OUT WITH STABILITY RETURNING.
PATCHES OF LIGHT SNOW WILL LINGER THRU MID-MORNING...BUT THE
ACCUMULATING SNOW WILL ESSENTIALLY BE OVER. PLENTY OF CLOUDS WILL
REMAIN AND A FEW FLURRIES COULD REDEVELOP N AND W OF THE TRI-
CITIES IN THE AFTERNOON.
HIGH TEMPS HAVE A LOT OF CONTINUITY WITH THE 4 AM GID FCST. THE
ONLY CHANGE WAS TO NUDGE TEMPS DOWN E OF HWY 281.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 407 PM CST SAT FEB 22 2014
THE BIG STORY WILL BE THE WELL BELOW NORMAL TEMPERATURES ALONG
WITH SEVERAL CHANCES OF WINTRY PRECIPITATION. HIGH TEMPERATURES
THROUGH THE PERIOD WILL GENERALLY AVERAGE 10 TO 15 DEGREES BELOW
NORMAL.
SUNDAY NIGHT AND MONDAY...MID LEVEL ISENTROPIC LIFT WILL RESULT
IN SOME LOW END LIGHT SNOW CHANCES PRIMARILY ACROSS OUR NORTHERN
ZONES WITH THE BETTER SNOW CHANCES WELL NORTH OF OUR FORECAST AREA
ACROSS SOUTH DAKOTA. ALTHOUGH NOT IN THE OFFICIAL FORECAST AS OF
RIGHT NOW...WILL ALSO NEED TO WATCH OUT FOR THE POSSIBILITY OF
LIGHT FREEZING DRIZZLE ACROSS OUR NORTHERN AND WESTERN ZONES LATE
SUNDAY NIGHT INTO EARLY MONDAY MORNING. ANY FREEZING DRIZZLE WOULD
PRIMARILY BE CONFINED TO OUR WESTERN AND NORTHERN ZONES. THE 12Z
GFS AND ECMWF DO NOT REALLY SHOW MUCH IN THE WAY OF FREEZING
DRIZZLE POTENTIAL...BUT THE 12Z AND 18Z NAM DO INDICATE SOME
POTENTIAL WITH LOW LEVEL SATURATION BENEATH A DRY MID LEVEL. THE
NAM IS STILL A BIT OF AN OUTLIER AND THE POTENTIAL EVEN IN THE NAM
IS SO MARGINAL THAT WE WILL CONTINUE TO LEAVE FREEZING DRIZZLE OUT
OF THE FORECAST FOR NOW. ANY SNOW AMOUNTS WOULD LIKELY BE VERY
LIGHT AND LESS THAN ONE HALF INCH.
MONDAY NIGHT THROUGH TUESDAY...A SHORTWAVE TROUGH WILL TRACK
SOUTHEAST OUT OF CANADA. ASSOCIATED UPPER JET DYNAMICS AND A
PROGRESSIVE BAND OF MID LEVEL FRONTOGENESIS WILL LEAD TO
ADDITIONAL CHANCES FOR LIGHT SNOW. NOT EXPECTING MUCH SNOW AT
THIS TIME WITH MOST PLACES SEEING FLURRIES UP TO 1 INCH. COLDER
AIR WILL FILTER IN ON TUESDAY WITH HIGHS STUCK IN THE 20S FOR MOST
AREAS.
WEDNESDAY THROUGH SATURDAY...WILL TRANSITION FROM A NORTHWESTERLY
FLOW PATTERN TO A MORE ZONAL PATTERN...WITH PERHAPS EVEN THE
DEVELOPMENT OF A TROUGH OVER THE WESTERN CONUS LATE IN THE PERIOD.
OVERALL...THIS IS MORE LIKELY BE A DRY AND COOL PERIOD FOR OUR
FORECAST AREA.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1156 AM CST SAT FEB 22 2014
THIS AFTERNOON: VFR WITH SLOWLY INVADING MULTI-LAYERED CLOUDS
ABOVE 10K FT. NE WINDS 10-15 KTS. CONFIDENCE: HIGH
TONIGHT: CIGS LOWER STEADILY WITH MVFR CIGS ARRIVING 02Z-04Z AND
SHOULD QUICKLY LOWER TO IFR/LIFR 04Z-06Z AS SNOW OVERSPREADS.
THERE IS UNCERTAINTY IN THE LOCATION AND TIMING OF WHAT COULD BE A
FAIRLY NARROW BAND OF SNOW. NE WINDS AROUND 10 KTS.
CONFIDENCE: MEDIUM
SUN MORNING: VSBYS SHOULD IMPROVE TO MVFR BY 13Z AS THE SNOW
LIGHTENS UP OR ENDS ALTOGETHER. CIGS REMAIN UNCERTAIN AND FCST
GUIDANCE IS OF MINIMAL HELP. SO HAVE INDICATED SOME GRADUAL
UPWARD STEPS...IMPROVING TO MVFR. N WINDS AROUND 10 KTS.
CONFIDENCE: LOW
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...WINTER WEATHER ADVISORY UNTIL NOON CST SUNDAY FOR NEZ060-061-072.
KS...NONE.
&&
$$
SHORT TERM...HALBLAUB
LONG TERM...WESELY
AVIATION...HALBLAUB
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1136 AM CST SAT FEB 22 2014
.UPDATE...
ISSUED AT 653 AM CST SAT FEB 22 2014
ANALYSIS OF WATER VAPOR IN CONJUNCTION WITH THE NAM...SREF...UKMET
AND ARF/NMM SOLNS SUGGESTS THE POTENTIAL FOR A COUPLED 500 MB JET
DEVELOPING NEAR OR ACROSS SWRN NEB THIS EVENING. THESE MODELS ARE
THE HEAVY HITTERS WITH QPF ACROSS THE FCST AREA. THE SPEED MAX IS
CURRENTLY ALONG THE COAST OF BRITISH COLUMBIA AND MOVING RAPIDLY
SOUTH AS FCST BY THE NAM. TIMING TOOLS SUGGEST IS COULD REACH ERN
WY BY 18Z WHICH IS MUCH FASTER THAN ANY MODEL SHOWS.
NONETHELESS...IF THIS JET MAX CAN MAINTAIN ITS 75 KT INTENSITY AND
COUPLE WITH THE DEPARTING MIDWEST JET THIS EVENING...HEAVY SNOW
WOULD DEVELOP AS INDICATED BY THE NAM. ITS UNCERTAIN WHY THE
GFS AND ECM DONT SHOW THIS DEVELOPMENT BUT DEPENDING ON THE
LOCATION OF THE COUPLE...NERN COLO/SERN WY/SRN NEB PANHANDLE VS
SWRN NEB...THE POTENTIAL FOR HEAVY SNOW REMAINS UNDER EVALUATION.
THERE ARE NO CHANGES TO THE FCST ATTM.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 351 AM CST SAT FEB 22 2014
THE MODELS...ESPECIALLY THE NAM...ARE ADVERTISING A
FRONTOGENETICALLY FORCED SNOW EVENT LATER TODAY THROUGH SUNDAY
MORNING. THE NAM IS THE STRONGEST WITH THE FRONTOGENESIS AND
RESULTING LIFT. THE LOCATION OF THE SNOW BAND SHOWN BY THE MODELS
APPEARS TO BE TRENDING SOUTH IN THE ECM...GFS...06Z NAM AND GEM
REG FAVORING SWRN NEB SOUTH OF INTERSTATE 80 WHILE THE 03Z
SREF...00Z NAM AND GEMNH MODELS PREFER INTERSTATE 80 AND THEN UP
THE NORTH PLATTE VALLEY. THIS IS A DIFFERENCE OF ABOUT 50 MILES
WHICH IS NORMAL. A BLEND OF THE 06Z NAM AND THE OTHER MODELS
PRODUCED 3 TO 5 INCHES OF SNOW BLENDED ACROSS THE AFOREMENTIONED
AREAS WITH HIGHEST AMOUNTS JUST SOUTH OF INTERSTATE 80 IN LINCOLN
COUNTY.
THE COBB SNOW TO LIQUID METHODOLOGY USING THE NAM AND GFS IN THE
800-600 MB LAYER PRODUCED A 19 TO 1 RATIO IN THE 00Z RUNS BUT THE
06Z NAM CAME IN AROUND 17 TO 1. SINCE 19 TO 1 IS VERY HIGH...17 TO
1 WAS USED WHICH IS CLOSER CLIMATOLOGY.
THE NAM VISIBILITY PRODUCT SUGGESTS VISIBILITY FALLING TO 1/2
MILE AT TIMES. MEANWHILE FOLDED THETA E AND DEEP LIFT IN A
SATURATED DENDRITIC LAYER SUGGESTS A PERIOD OF INCH AN HOUR
ACCUMULATION. A WINTER WEATHER ADVISORY IS IN PLACE FOR THIS
EVENT WHERE 3 INCHES OR MORE SNOW IS FORECAST.
OTHERWISE...THE MAINSTREAM MODELS HAVE NOT CAPTURED THE RESIDENT
SFC MOISTURE THIS MORNING WHICH MAY BE THE REASON SOME SOLNS LIKE
THE ECM ARE VERY DRY. A BLEND OF THE HRRR AND RAP WAS USED FOR
DEW POINTS TODAY AND THE 08Z RAP SHOWS PCPN FILLING IN ACROSS
SWRN NEB THIS EVENING LIKE THE 06Z NAM SHOWED. A WEAK ARCTIC
FRONT...CURRENTLY NEAR KHON...WILL MOVE PART WAY INTO THE FCST
AREA TODAY INDUCING UPSLOPE FLOW AND THIS SHOULD POOL LOW LEVEL
MOISTURE ACROSS SWRN NEB.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 351 AM CST SAT FEB 22 2014
ONGOING SNOW ACROSS SOUTHWEST NEBRASKA WILL BE DIMINISHING SUNDAY
MORNING AS THE NORTHWEST FLOW CONTINUES TO PUSH THE DISTURBANCE
TO THE SOUTHEAST. HOWEVER A SECOND DISTURBANCE WILL BE QUICK TO
MOVE TOWARDS THE CWA BY SUNDAY AFTERNOON. THIS NEXT WAVE MODELS
HAVE DECENT AGREEMENT WITH A MORE NORTHERN TRACK...COMPARED TO
THE FIRST WAVE. BY SUNDAY AFTERNOON SNOW WILL BE ON THE INCREASE
ACROSS NW NEB WHICH WILL PROGRESS EAST...ACROSS NORTH
CENTRAL...SUNDAY NIGHT BEFORE DIMINISHING ON MONDAY. MODELS SHOW
BEST LIFT NEAR THE NEB/S DAKOTA BORDER SUNDAY NIGHT...AHEAD OF A
140 PLUS KT JET STREAK AT 300 MB. PWATS INCREASE TO GREATER THAN
0.3 INCHES...WITH A FGEN BAND TO RESULT IN DECENT WINDOW FOR SNOW
PRODUCTION...WITH AROUND A 17:1 RATIO. SNOW TOTALS OF 2 TO 3
INCHES LOOK LIKELY...HOWEVER WILL NEED TO MONITOR AS IT WOULD NOT
TAKE MUCH TO INCREASE THIS TO 4 OR 5 INCHES WHICH WOULD RESULT IN
THE NEED FOR AN ADVISORY.
BY MONDAY NIGHT INTO TUESDAY YET ANOTHER DISTURBANCE WILL BE
CROSSING THE HIGH PLAINS. THIS TIME MODELS FAVOR A SOUTHERN
TRACK...BACK OVER THE SOUTHERN PANHANDLE INTO SW NEB. POPS ONLY
IN THE LOW CHANCE CATEGORY AS MODEL SPREAD HAS INCREASED...ALONG
WITH AVAILABLE MOISTURE. COLD DRIER AIR...WITH ARCTIC HIGH
PRESSURE DRIFTING SOUTH ACROSS THE NORTHERN PLAINS. THIS HAS THE
POTENTIAL TO EITHER PUSH THE SNOW FURTHER SOUTH...OR BRING DRIER
AIR WHICH WILL RESULT IN LESS SNOW REACHING THE GROUND. STAY
TUNED TO AS CHANGES TO AMOUNTS ARE EXPECTED.
TEMPERATURES TO START OFF THE WEEK WILL BE BELOW NORMAL AS
SNOW/CLOUDS KEEP TEMPS FROM SEEING MUCH OF A DIURNAL SWING. HIGHS
GENERALLY SHOULD HOLD IN THE 20S TO MID 30S. SW NEB MAY PUSH
CLOSE TO 40 ON MONDAY WITH A LITTLE MORE SUN INBETWEEN SYSTEMS.
BY TUESDAY NIGHT THE ARCTIC HIGH PRESSURE WILL BUILD OVERHEAD.
LOWS AS SKIES CLEAR IN THE SINGLE DIGITS...ALTHOUGH WITH A SNOW
PACK TEMPS COULD DIP BELOW ZERO. RECORDS ARE STILL IN THE DOUBLE
DIGIT BELOW ZERO...SO LOWS IN THE SINGLE DIGITS BELOW ZERO ARE
STILL EASY TO HIT...ESPECIALLY IF SKIES CLEAR EARLY IN THE NIGHT
WITH A FRESH SNOW COVER.
ARCTIC HIGH SLIDES EAST BY WED...MEANWHILE MODELS TRY TO BUILD
THE WESTERN RIDGE SLOWLY TO THE EAST. STILL LOOKING MAINLY DRY
WITH THE STORM TRACK OVER THE GREAT LAKES. HIGHS BELOW NORMAL AS
WE GO THROUGH MID TO LATE WEEK...ALTHOUGH LESS CONFIDENCE IN
TEMPS BY THE END OF THE WEEK. LATEST MEX GUIDANCE IS WARMER IN
THE EXTENDED...HOWEVER THE ECMWF GUIDANCE RECYCLES A SECOND HIGH
PRESSURE AND COLD AIR ACROSS THE HIGH PLAINS. EXAMPLE OF RANGE
INCLUDE FRIDAY MAX T GUIDANCE OF EITHER 42 FROM THE MEX OR 21
FROM THE EC FOR KLBF. EVEN THE ENSEMBLE RANGE FROM BOTH MODELS IS
HIGH...WITH HIGHS RANGING FROM THE 40S TO THE TEENS. FORECAST
UNCHANGED FROM THE ALLBLEND AND WILL WAIT TO SEE WHICH SIDE OF
THE AISLE WE END UP...ALTHOUGH THIS TYPE OF PATTERN CAN BE
FAVORABLE OF A LARGE SPREAD ACROSS THE CWA.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1135 AM CST SAT FEB 22 2014
MAIN CONCERN IN THE CURRENT TAF PERIOD IS SNOW AND POTENTIAL LIFR
CONDITIONS AT KLBF. LOW LEVEL CIGS WILL CONTINUE TO SPREAD EAST
ACROSS WESTERN NEBRASKA THROUGH THE AFTERNOON. KVTN ALREADY INTO
MVFR AND EXPECTING MVFR AT KLBF AROUND 22Z.
SNOWFALL STARTS TO MOVE INTO WESTERN AND SOUTHWEST NEBRASKA THIS
AFTERNOON AND EVENING. HEAVIEST SNOWFALL IS EXPECTED DURING THE
OVERNIGHT WHICH MAY BRING KLBF INTO LIFR CATEGORY. SNOWFALL ACROSS
NORTHERN NEBRASKA AND KVTN EXPECTED TO BE DELAYED AND NOT AS
INTENSE.
WINTRY WEATHER WILL STICK AROUND INTO SUNDAY MORNING AND SLOWLY
BEGIN TO TAPER OFF.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 6 PM CST /5 PM MST/ THIS EVENING TO
NOON CST /11 AM MST/ SUNDAY FOR NEZ022-023-035-036-056>059-070-
071.
&&
$$
UPDATE...CDC
SHORT TERM...CDC
LONG TERM...MASEK
AVIATION...MARTIN
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
706 AM CST SAT FEB 22 2014
.UPDATE...
ISSUED AT 653 AM CST SAT FEB 22 2014
ANALYSIS OF WATER VAPOR IN CONJUNCTION WITH THE NAM...SREF...UKMET
AND ARF/NMM SOLNS SUGGESTS THE POTENTIAL FOR A COUPLED 500 MB JET
DEVELOPING NEAR OR ACROSS SWRN NEB THIS EVENING. THESE MODELS ARE
THE HEAVY HITTERS WITH QPF ACROSS THE FCST AREA. THE SPEED MAX IS
CURRENTLY ALONG THE COAST OF BRITISH COLUMBIA AND MOVING RAPIDLY
SOUTH AS FCST BY THE NAM. TIMING TOOLS SUGGEST IS COULD REACH ERN
WY BY 18Z WHICH IS MUCH FASTER THAN ANY MODEL SHOWS.
NONETHELESS...IF THIS JET MAX CAN MAINTAIN ITS 75 KT INTENSITY AND
COUPLE WITH THE DEPARTING MIDWEST JET THIS EVENING...HEAVY SNOW
WOULD DEVELOP AS INDICATED BY THE NAM. ITS UNCERTAIN WHY THE
GFS AND ECM DONT SHOW THIS DEVELOPMENT BUT DEPENDING ON THE
LOCATION OF THE COUPLE...NERN COLO/SERN WY/SRN NEB PANHANDLE VS
SWRN NEB...THE POTENTIAL FOR HEAVY SNOW REMAINS UNDER EVALUATION.
THERE ARE NO CHANGES TO THE FCST ATTM.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 351 AM CST SAT FEB 22 2014
THE MODELS...ESPECIALLY THE NAM...ARE ADVERTISING A
FRONTOGENETICALLY FORCED SNOW EVENT LATER TODAY THROUGH SUNDAY
MORNING. THE NAM IS THE STRONGEST WITH THE FRONTOGENESIS AND
RESULTING LIFT. THE LOCATION OF THE SNOW BAND SHOWN BY THE MODELS
APPEARS TO BE TRENDING SOUTH IN THE ECM...GFS...06Z NAM AND GEM
REG FAVORING SWRN NEB SOUTH OF INTERSTATE 80 WHILE THE 03Z
SREF...00Z NAM AND GEMNH MODELS PREFER INTERSTATE 80 AND THEN UP
THE NORTH PLATTE VALLEY. THIS IS A DIFFERENCE OF ABOUT 50 MILES
WHICH IS NORMAL. A BLEND OF THE 06Z NAM AND THE OTHER MODELS
PRODUCED 3 TO 5 INCHES OF SNOW BLENDED ACROSS THE AFOREMENTIONED
AREAS WITH HIGHEST AMOUNTS JUST SOUTH OF INTERSTATE 80 IN LINCOLN
COUNTY.
THE COBB SNOW TO LIQUID METHODOLOGY USING THE NAM AND GFS IN THE
800-600 MB LAYER PRODUCED A 19 TO 1 RATIO IN THE 00Z RUNS BUT THE
06Z NAM CAME IN AROUND 17 TO 1. SINCE 19 TO 1 IS VERY HIGH...17 TO
1 WAS USED WHICH IS CLOSER CLIMATOLOGY.
THE NAM VISIBILITY PRODUCT SUGGESTS VISIBILITY FALLING TO 1/2
MILE AT TIMES. MEANWHILE FOLDED THETA E AND DEEP LIFT IN A
SATURATED DENDRITIC LAYER SUGGESTS A PERIOD OF INCH AN HOUR
ACCUMULATION. A WINTER WEATHER ADVISORY IS IN PLACE FOR THIS
EVENT WHERE 3 INCHES OR MORE SNOW IS FORECAST.
OTHERWISE...THE MAINSTREAM MODELS HAVE NOT CAPTURED THE RESIDENT
SFC MOISTURE THIS MORNING WHICH MAY BE THE REASON SOME SOLNS LIKE
THE ECM ARE VERY DRY. A BLEND OF THE HRRR AND RAP WAS USED FOR
DEW POINTS TODAY AND THE 08Z RAP SHOWS PCPN FILLING IN ACROSS
SWRN NEB THIS EVENING LIKE THE 06Z NAM SHOWED. A WEAK ARCTIC
FRONT...CURRENTLY NEAR KHON...WILL MOVE PART WAY INTO THE FCST
AREA TODAY INDUCING UPSLOPE FLOW AND THIS SHOULD POOL LOW LEVEL
MOISTURE ACROSS SWRN NEB.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 351 AM CST SAT FEB 22 2014
ONGOING SNOW ACROSS SOUTHWEST NEBRASKA WILL BE DIMINISHING SUNDAY
MORNING AS THE NORTHWEST FLOW CONTINUES TO PUSH THE DISTURBANCE
TO THE SOUTHEAST. HOWEVER A SECOND DISTURBANCE WILL BE QUICK TO
MOVE TOWARDS THE CWA BY SUNDAY AFTERNOON. THIS NEXT WAVE MODELS
HAVE DECENT AGREEMENT WITH A MORE NORTHERN TRACK...COMPARED TO
THE FIRST WAVE. BY SUNDAY AFTERNOON SNOW WILL BE ON THE INCREASE
ACROSS NW NEB WHICH WILL PROGRESS EAST...ACROSS NORTH
CENTRAL...SUNDAY NIGHT BEFORE DIMINISHING ON MONDAY. MODELS SHOW
BEST LIFT NEAR THE NEB/S DAKOTA BORDER SUNDAY NIGHT...AHEAD OF A
140 PLUS KT JET STREAK AT 300 MB. PWATS INCREASE TO GREATER THAN
0.3 INCHES...WITH A FGEN BAND TO RESULT IN DECENT WINDOW FOR SNOW
PRODUCTION...WITH AROUND A 17:1 RATIO. SNOW TOTALS OF 2 TO 3
INCHES LOOK LIKELY...HOWEVER WILL NEED TO MONITOR AS IT WOULD NOT
TAKE MUCH TO INCREASE THIS TO 4 OR 5 INCHES WHICH WOULD RESULT IN
THE NEED FOR AN ADVISORY.
BY MONDAY NIGHT INTO TUESDAY YET ANOTHER DISTURBANCE WILL BE
CROSSING THE HIGH PLAINS. THIS TIME MODELS FAVOR A SOUTHERN
TRACK...BACK OVER THE SOUTHERN PANHANDLE INTO SW NEB. POPS ONLY
IN THE LOW CHANCE CATEGORY AS MODEL SPREAD HAS INCREASED...ALONG
WITH AVAILABLE MOISTURE. COLD DRIER AIR...WITH ARCTIC HIGH
PRESSURE DRIFTING SOUTH ACROSS THE NORTHERN PLAINS. THIS HAS THE
POTENTIAL TO EITHER PUSH THE SNOW FURTHER SOUTH...OR BRING DRIER
AIR WHICH WILL RESULT IN LESS SNOW REACHING THE GROUND. STAY
TUNED TO AS CHANGES TO AMOUNTS ARE EXPECTED.
TEMPERATURES TO START OFF THE WEEK WILL BE BELOW NORMAL AS
SNOW/CLOUDS KEEP TEMPS FROM SEEING MUCH OF A DIURNAL SWING. HIGHS
GENERALLY SHOULD HOLD IN THE 20S TO MID 30S. SW NEB MAY PUSH
CLOSE TO 40 ON MONDAY WITH A LITTLE MORE SUN INBETWEEN SYSTEMS.
BY TUESDAY NIGHT THE ARCTIC HIGH PRESSURE WILL BUILD OVERHEAD.
LOWS AS SKIES CLEAR IN THE SINGLE DIGITS...ALTHOUGH WITH A SNOW
PACK TEMPS COULD DIP BELOW ZERO. RECORDS ARE STILL IN THE DOUBLE
DIGIT BELOW ZERO...SO LOWS IN THE SINGLE DIGITS BELOW ZERO ARE
STILL EASY TO HIT...ESPECIALLY IF SKIES CLEAR EARLY IN THE NIGHT
WITH A FRESH SNOW COVER.
ARCTIC HIGH SLIDES EAST BY WED...MEANWHILE MODELS TRY TO BUILD
THE WESTERN RIDGE SLOWLY TO THE EAST. STILL LOOKING MAINLY DRY
WITH THE STORM TRACK OVER THE GREAT LAKES. HIGHS BELOW NORMAL AS
WE GO THROUGH MID TO LATE WEEK...ALTHOUGH LESS CONFIDENCE IN
TEMPS BY THE END OF THE WEEK. LATEST MEX GUIDANCE IS WARMER IN
THE EXTENDED...HOWEVER THE ECMWF GUIDANCE RECYCLES A SECOND HIGH
PRESSURE AND COLD AIR ACROSS THE HIGH PLAINS. EXAMPLE OF RANGE
INCLUDE FRIDAY MAX T GUIDANCE OF EITHER 42 FROM THE MEX OR 21
FROM THE EC FOR KLBF. EVEN THE ENSEMBLE RANGE FROM BOTH MODELS IS
HIGH...WITH HIGHS RANGING FROM THE 40S TO THE TEENS. FORECAST
UNCHANGED FROM THE ALLBLEND AND WILL WAIT TO SEE WHICH SIDE OF
THE AISLE WE END UP...ALTHOUGH THIS TYPE OF PATTERN CAN BE
FAVORABLE OF A LARGE SPREAD ACROSS THE CWA.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 526 AM CST SAT FEB 22 2014
MVFR ACROSS NRN NEB ALONG KVTN-KANW-KONL IS EXPECTED TO MOVE
SLOWLY SOUTH THIS MORNING AND PERHAPS MIX OUT TO A VFR CIG NEAR
OVC035 AS INDICATED IN THE NAM MODEL. THE RAP MODEL DOES NOT SHOW
THIS SO THERE IS UNCERTAINTY IN THE FORECAST.
THE MODEL CONSENSUS SHOWS MVFR IN SNOW DEVELOPING THIS AFTERNOON
ACROSS NWRN NEB WHICH SHOULD SPREAD SOUTH AND EAST LATE IN THE
AFTERNON AND TONIGHT. THE SNOW SHOULD BECOME MODERATE TONIGHT WITH
IFR/LIFR BECOMING FAIRLY WIDESPREAD BY 03Z...SOUTH OF A LINE FROM
KIEN TO KTIF TO KBBW.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 6 PM CST /5 PM MST/ THIS EVENING TO
NOON CST /11 AM MST/ SUNDAY FOR NEZ022-023-035-036-056>059-070-
071.
&&
$$
UPDATE...CDC
SHORT TERM...CDC
LONG TERM...MASEK
AVIATION...CDC
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
527 AM CST SAT FEB 22 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 351 AM CST SAT FEB 22 2014
THE MODELS...ESPECIALLY THE NAM...ARE ADVERTISING A
FRONTOGENETICALLY FORCED SNOW EVENT LATER TODAY THROUGH SUNDAY
MORNING. THE NAM IS THE STRONGEST WITH THE FRONTOGENESIS AND
RESULTING LIFT. THE LOCATION OF THE SNOW BAND SHOWN BY THE MODELS
APPEARS TO BE TRENDING SOUTH IN THE ECM...GFS...06Z NAM AND GEM
REG FAVORING SWRN NEB SOUTH OF INTERSTATE 80 WHILE THE 03Z
SREF...00Z NAM AND GEMNH MODELS PREFER INTERSTATE 80 AND THEN UP
THE NORTH PLATTE VALLEY. THIS IS A DIFFERENCE OF ABOUT 50 MILES
WHICH IS NORMAL. A BLEND OF THE 06Z NAM AND THE OTHER MODELS
PRODUCED 3 TO 5 INCHES OF SNOW BLENDED ACROSS THE AFOREMENTIONED
AREAS WITH HIGHEST AMOUNTS JUST SOUTH OF INTERSTATE 80 IN LINCOLN
COUNTY.
THE COBB SNOW TO LIQUID METHODOLOGY USING THE NAM AND GFS IN THE
800-600 MB LAYER PRODUCED A 19 TO 1 RATIO IN THE 00Z RUNS BUT THE
06Z NAM CAME IN AROUND 17 TO 1. SINCE 19 TO 1 IS VERY HIGH...17 TO
1 WAS USED WHICH IS CLOSER CLIMATOLOGY.
THE NAM VISIBILITY PRODUCT SUGGESTS VISIBILITY FALLING TO 1/2
MILE AT TIMES. MEANWHILE FOLDED THETA E AND DEEP LIFT IN A
SATURATED DENDRITIC LAYER SUGGESTS A PERIOD OF INCH AN HOUR
ACCUMULATION. A WINTER WEATHER ADVISORY IS IN PLACE FOR THIS
EVENT WHERE 3 INCHES OR MORE SNOW IS FORECAST.
OTHERWISE...THE MAINSTREAM MODELS HAVE NOT CAPTURED THE RESIDENT
SFC MOISTURE THIS MORNING WHICH MAY BE THE REASON SOME SOLNS LIKE
THE ECM ARE VERY DRY. A BLEND OF THE HRRR AND RAP WAS USED FOR
DEW POINTS TODAY AND THE 08Z RAP SHOWS PCPN FILLING IN ACROSS
SWRN NEB THIS EVENING LIKE THE 06Z NAM SHOWED. A WEAK ARCTIC
FRONT...CURRENTLY NEAR KHON...WILL MOVE PART WAY INTO THE FCST
AREA TODAY INDUCING UPSLOPE FLOW AND THIS SHOULD POOL LOW LEVEL
MOISTURE ACROSS SWRN NEB.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 351 AM CST SAT FEB 22 2014
ONGOING SNOW ACROSS SOUTHWEST NEBRASKA WILL BE DIMINISHING SUNDAY
MORNING AS THE NORTHWEST FLOW CONTINUES TO PUSH THE DISTURBANCE
TO THE SOUTHEAST. HOWEVER A SECOND DISTURBANCE WILL BE QUICK TO
MOVE TOWARDS THE CWA BY SUNDAY AFTERNOON. THIS NEXT WAVE MODELS
HAVE DECENT AGREEMENT WITH A MORE NORTHERN TRACK...COMPARED TO
THE FIRST WAVE. BY SUNDAY AFTERNOON SNOW WILL BE ON THE INCREASE
ACROSS NW NEB WHICH WILL PROGRESS EAST...ACROSS NORTH
CENTRAL...SUNDAY NIGHT BEFORE DIMINISHING ON MONDAY. MODELS SHOW
BEST LIFT NEAR THE NEB/S DAKOTA BORDER SUNDAY NIGHT...AHEAD OF A
140 PLUS KT JET STREAK AT 300 MB. PWATS INCREASE TO GREATER THAN
0.3 INCHES...WITH A FGEN BAND TO RESULT IN DECENT WINDOW FOR SNOW
PRODUCTION...WITH AROUND A 17:1 RATIO. SNOW TOTALS OF 2 TO 3
INCHES LOOK LIKELY...HOWEVER WILL NEED TO MONITOR AS IT WOULD NOT
TAKE MUCH TO INCREASE THIS TO 4 OR 5 INCHES WHICH WOULD RESULT IN
THE NEED FOR AN ADVISORY.
BY MONDAY NIGHT INTO TUESDAY YET ANOTHER DISTURBANCE WILL BE
CROSSING THE HIGH PLAINS. THIS TIME MODELS FAVOR A SOUTHERN
TRACK...BACK OVER THE SOUTHERN PANHANDLE INTO SW NEB. POPS ONLY
IN THE LOW CHANCE CATEGORY AS MODEL SPREAD HAS INCREASED...ALONG
WITH AVAILABLE MOISTURE. COLD DRIER AIR...WITH ARCTIC HIGH
PRESSURE DRIFTING SOUTH ACROSS THE NORTHERN PLAINS. THIS HAS THE
POTENTIAL TO EITHER PUSH THE SNOW FURTHER SOUTH...OR BRING DRIER
AIR WHICH WILL RESULT IN LESS SNOW REACHING THE GROUND. STAY
TUNED TO AS CHANGES TO AMOUNTS ARE EXPECTED.
TEMPERATURES TO START OFF THE WEEK WILL BE BELOW NORMAL AS
SNOW/CLOUDS KEEP TEMPS FROM SEEING MUCH OF A DIURNAL SWING. HIGHS
GENERALLY SHOULD HOLD IN THE 20S TO MID 30S. SW NEB MAY PUSH
CLOSE TO 40 ON MONDAY WITH A LITTLE MORE SUN INBETWEEN SYSTEMS.
BY TUESDAY NIGHT THE ARCTIC HIGH PRESSURE WILL BUILD OVERHEAD.
LOWS AS SKIES CLEAR IN THE SINGLE DIGITS...ALTHOUGH WITH A SNOW
PACK TEMPS COULD DIP BELOW ZERO. RECORDS ARE STILL IN THE DOUBLE
DIGIT BELOW ZERO...SO LOWS IN THE SINGLE DIGITS BELOW ZERO ARE
STILL EASY TO HIT...ESPECIALLY IF SKIES CLEAR EARLY IN THE NIGHT
WITH A FRESH SNOW COVER.
ARCTIC HIGH SLIDES EAST BY WED...MEANWHILE MODELS TRY TO BUILD
THE WESTERN RIDGE SLOWLY TO THE EAST. STILL LOOKING MAINLY DRY
WITH THE STORM TRACK OVER THE GREAT LAKES. HIGHS BELOW NORMAL AS
WE GO THROUGH MID TO LATE WEEK...ALTHOUGH LESS CONFIDENCE IN
TEMPS BY THE END OF THE WEEK. LATEST MEX GUIDANCE IS WARMER IN
THE EXTENDED...HOWEVER THE ECMWF GUIDANCE RECYCLES A SECOND HIGH
PRESSURE AND COLD AIR ACROSS THE HIGH PLAINS. EXAMPLE OF RANGE
INCLUDE FRIDAY MAX T GUIDANCE OF EITHER 42 FROM THE MEX OR 21
FROM THE EC FOR KLBF. EVEN THE ENSEMBLE RANGE FROM BOTH MODELS IS
HIGH...WITH HIGHS RANGING FROM THE 40S TO THE TEENS. FORECAST
UNCHANGED FROM THE ALLBLEND AND WILL WAIT TO SEE WHICH SIDE OF
THE AISLE WE END UP...ALTHOUGH THIS TYPE OF PATTERN CAN BE
FAVORABLE OF A LARGE SPREAD ACROSS THE CWA.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 526 AM CST SAT FEB 22 2014
MVFR ACROSS NRN NEB ALONG KVTN-KANW-KONL IS EXPECTED TO MOVE
SLOWLY SOUTH THIS MORNING AND PERHAPS MIX OUT TO A VFR CIG NEAR
OVC035 AS INDICATED IN THE NAM MODEL. THE RAP MODEL DOES NOT SHOW
THIS SO THERE IS UNCERTAINTY IN THE FORECAST.
THE MODEL CONSENSUS SHOWS MVFR IN SNOW DEVELOPING THIS AFTERNOON
ACROSS NWRN NEB WHICH SHOULD SPREAD SOUTH AND EAST LATE IN THE
AFTERNON AND TONIGHT. THE SNOW SHOULD BECOME MODERATE TONIGHT WITH
IFR/LIFR BECOMING FAIRLY WIDESPREAD BY 03Z...SOUTH OF A LINE FROM
KIEN TO KTIF TO KBBW.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 6 PM CST /5 PM MST/ THIS EVENING TO
NOON CST /11 AM MST/ SUNDAY FOR NEZ022-023-035-036-056>059-070-
071.
&&
$$
SHORT TERM...CDC
LONG TERM...MASEK
AVIATION...CDC
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1120 PM CST FRI FEB 21 2014
.SHORT TERM...(THIS AFTERNOON THROUGH MONDAY)
ISSUED AT 159 PM CST FRI FEB 21 2014
A BROAD CYCLONIC CIRCULATION IS INDICATED BY 12Z MODEL RUNS TO
REMAIN IN PLACE ACROSS MUCH OF THE NORTHERN HALF OF THE NATION
DURING THE PERIOD. THIS WILL RESULT IN TEMPERATURES TRENDING
COLDER THROUGH THE PERIOD WITH A CHANCE OF SNOW COMING INTO THE
AREA SUNDAY NIGHT INTO MONDAY.
A RATHER SHARP THERMAL GRADIENT WAS IN PLACE ACROSS THE REGION
AT 20Z WITH THE BOUNDARY STRETCHING FROM CENTRAL SOUTH DAKOTA
THROUGH NORTHEAST IOWA AND NORTHERN ILLINOIS. A WEAK SURFACE WAVE
IS FORECAST TO TRACK SOUTHEAST ALONG THIS GRADIENT TONIGHT AND
BE OVER CENTRAL ILLINOIS BY SATURDAY MORNING. SHORT RANGE MODELS
INDICATE SOME POTENTIAL FOR LIGHT SNOW NORTH OF THE WAVE LATE
TONIGHT. QPF LOOKS A BIT OVERDONE BY THE RAP COMPARED TO THE LONG
RANGE MODELS BUT HAVE INCLUDED A MENTION OF SCATTERED FLURRIES
FOR NORTHEAST NEBRASKA INTO SOUTHWEST IOWA AS THIS FEATURE MOVES
THROUGH TONIGHT.
THE COLD FRONT ASSOCIATED WITH THE WEAK LOW SINKS SOUTH INTO THE
SOUTHERN PLAINS AND LOWER OHIO VALLEY ON SATURDAY WITH COLD AIR
SLOWLY MOVING SOUTH BEHIND THE FRONT. SOME LIGHT SNOW BREAKS OUT
OVER THE WESTERN HIGH PLAINS SATURDAY AFTERNOON AS UPSLOPE FLOW
DEVELOPS AND CONTINUES SATURDAY NIGHT WITH SOME SPREAD TO THE EAST
INTO SOUTH CENTRAL NEBRASKA ASSOCIATED WITH WEAK ISENTROPIC
FORCING. HAVE BACKED OFF A BIT ON POPS FOR SOUTHWEST PORTION OF
THE FA FOR LATE SATURDAY NIGHT WITH SOME SLIGHT POPS INTO SUNDAY
MORNING AS BETTER FORCING IS EXPECTED TO REMAIN FURTHER WEST.
WEAK CYCLOGENESIS OCCURS OVER SOUTHEAST WYOMING ON SUNDAY AS AN
UPPER WAVE BEGINS TO DROP INTO THE NORTHERN ROCKIES. SOUTHERLY LOW
LEVEL FLOW DEVELOPS OVER THE CENTRAL PLAINS SUNDAY NIGHT IN
RESPONSE TO THIS DEVELOPMENT WITH A STRONG BAROCLINIC ZONE OVER
NORTHERN NEBRASKA BY MONDAY MORNING. A WIDESPREAD AREA OF SNOW
IS LIKELY ALONG AND NORTH OF THIS BOUNDARY SUNDAY NIGHT INTO
MONDAY MORNING. SNOW THEN SPREADS EAST ON MONDAY INTO NORTHERN
IOWA AS THE UPPER WAVE TRACKS TOWARD THE UPPER MIDWEST WITH THE
BETTER CHANCE OF SNOW EXPECTED NORTH OF INTERSTATE 80. MUCH COLDER
AIR WILL ALSO SURGE INTO THE FA BEHIND THIS WAVE ON MONDAY.
.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 159 PM CST FRI FEB 21 2014
A COLD WINTER PATTERN WILL CONTINUE THROUGH THE PERIOD. ONE WEAK
WAVE WILL CONTINUE TO DRIFT SOUTHWARD AT THE BEGINNING OF THE
PERIOD...AND WITH H85 TEMPS WELL WITHIN THE DENDRITIC LAYER...COULD
SEE LINGERING FLURRIES MONDAY NIGHT...BUT LITTLE OR NO ACCUMULATION.
OTHERWISE...NORTHERLY FLOW WILL PERSIST TUESDAY AHEAD OF THE FIRST
SURGE OF EVEN COLDER AIR THAT ARRIVES TUESDAY NIGHT AND LINGERS
THROUGH WEDNESDAY...ALTHOUGH WESTERLY FLOW REDEVELOPS WEDNESDAY
WHICH SHOULD KEEP TEMPS IN THE 20S INSTEAD OF THE TEENS. A SECONDARY
SURGE OF COLDER TEMPS ARRIVES BY DAYBREAK THURSDAY AS SURFACE FLOW
AGAIN RETURNS TO THE NORTH/NORTHEAST. THIS SHOULD KEEP TEMPS IN THE
TEENS ON THURSDAY...BUT VERY LITTLE MOISTURE AVAILABLE SO NO CHANCE
OF PRECIP. A WEAK RETURN FLOW TRIES TO DEVELOP ON FRIDAY...BUT TEMPS
SHOULD REMAIN WELL BELOW NORMAL.
&&
.AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1120 PM CST FRI FEB 21 2014
PREVIOUS THINKING REMAINS ON TRACK. STILL EXPECT VFR CONDITIONS
THROUGH THE PERIOD WITH ANY CEILINGS ABOVE 5000 FEET. A COLD FRONT
WILL CONTINUE TO SETTLE SOUTHWARD ACROSS THE AREA WITH LIGHT WINDS
TENDING TO BECOME MORE NORTHERLY SATURDAY MORNING.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...FOBERT
LONG TERM...DEWALD
AVIATION...MILLER
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
333 AM EST SAT FEB 22 2014
.SYNOPSIS...
HIGH PRESSURE WILL BRING DRIER BUT CONTINUED WARM CONDITIONS INTO
THE AREA TODAY. THIS HIGH WILL MOVE OFFSHORE SUNDAY...FOLLOWED BY
A WEAK COLD FRONTAL PASSAGE SUNDAY NIGHT. SEASONABLE WEATHER IS
EXPECTED FOR EARLY NEXT WEEK. AN ARCTIC FRONT WILL CROSS THE
AREA WEDNESDAY...USHERING IN A RETURN TO MUCH COLDER WEATHER FOR
THE LATTER HALF OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 300 AM SATURDAY...AS CAN OFTEN BE THE CASE WITH COLD FRONTS
CROSSING THE NC MOUNTAINS...YESTERDAY`S DID NOT COME THROUGH IN
ONE PIECE. IN FACT THE SURFACE WIND SHIFT HAS YET TO ARRIVE IN SE
NORTH CAROLINA AND PLENTY OF MOISTURE REMAINS IN THE LOWEST 500
FEET OF THE ATMOSPHERE. FOG AND LOW STRATUS HAS BEEN THE
RESULT...ALTHOUGH THIS SHOULD CLEAR THE AREA BEFORE SUNRISE AS
NORTHERLY WINDS FINALLY ARRIVE AND ADVECT DEWPOINTS IN THE LOWER
40S DOWN TO THE BEACHES.
A ZONAL MID AND UPPER LEVEL FLOW ACROSS THE SOUTHERN U.S. WILL
CONTINUE THROUGH TONIGHT. A PAIR OF WEAK UPPER DISTURBANCES WILL
MOVE ACROSS THE AREA...THE FIRST THIS MORNING ACROSS NORTH CAROLINA
AND THE SECOND LATE TONIGHT ACROSS THE SOUTH CAROLINA/GEORGIA COAST.
EACH DISTURBANCE WILL HELP INDUCE A WEAK AREA OF SURFACE LOW
PRESSURE TO DEVELOP ALONG THE STALLED FRONT OFFSHORE. THE FIRST LOW
IS DEVELOPING NOW ACROSS NORTH FLORIDA AND IS BEST INDICATED BY THE
EXPANDING AREA OF LOW STRATUS CLOUDS ACROSS COASTAL GEORGIA DUE TO
WINDS BLOWING ACROSS THE FRONT ON THE 295K ISENTROPIC SURFACE
3000-4500 FT UP. THIS ZONE OF LIFT SHOULD ADVECT NORTHEASTWARD THIS
MORNING...PERHAPS SPREADING A FEW HOURS OF LOW CLOUDINESS ACROSS THE
NC/SC BEACHES AND NEARBY COASTAL AREAS. BY NOON ANY LOW CLOUDS
SHOULD BE BACK OFFSHORE AGAIN AS THE LOW SHOOTS BY TO THE EAST.
ASIDE FROM PATCHES OF TRANSLUCENT CIRRUS FROM TIME TO TIME IT SHOULD
BE A NICE DAY WITH HIGHS REACHING THE UPPER 60S AWAY FROM THE
BEACHES.
FOR TONIGHT GOOD RADIATIONAL COOLING DURING THE EVENING SHOULD ALLOW
TEMPERATURES TO FALL INTO THE 40S A FEW HOURS AFTER SUNSET. LOW
CLOUDS MAY BEGIN TO INCREASE FROM THE SOUTHEAST LATE TONIGHT AS THE
SECOND SURFACE LOW DEVELOPS ALONG THE FRONT OFFSHORE. LOWS SHOULD
END UP IN THE LOWER 40S FOR MOST AREAS.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 300 AM SATURDAY...SUNDAY WILL AGAIN FEATURE WELL ABOVE NORMAL
TEMPS FOR LATE FEBRUARY AS SURFACE HIGH PRESSURE EXTENDS NORTH FROM
THE GULF AND MID-LEVEL FLOW PERSISTS FROM THE SW. THIS WILL DRIVE
HIGHS WELL TOWARDS 70...WITH MANY PLACES LIKELY REACHING 70 AWAY
FROM THE COAST. THIS WELL ABOVE NORMAL WARMTH WILL BE SHORT-LIVED
HOWEVER...AS A COLD...BUT DRY...FRONT CROSSES THE CWA SUNDAY NIGHT.
STRONGEST CAA IS DELAYED SOMEWHAT BEHIND THE SURFACE BOUNDARY...SO
MINS SUNDAY NIGHT WILL REMAIN ABOVE NORMAL...FALLING ONLY INTO THE
MID 40S...BUT THEN HIGHS ON MONDAY WILL LIKELY STRUGGLE TO JUST
BELOW...OR RIGHT AT...SEASONABLE NORMS A LITTLE ABOVE 60. THE COOL
HIGH PRESSURE THAT BUILDS OVERHEAD MONDAY WILL QUICKLY MOVE OFFSHORE
AS THE MID-LEVEL FLOW REMAINS PROGRESSIVE...AND THUS RETURN FLOW
DEVELOPS LATE MONDAY NIGHT WHICH KEEPS MINS ONCE AGAIN SLIGHTLY
ABOVE NORMAL...AROUND 40 MOST PLACES.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 300 AM SATURDAY...UNSETTLED WEATHER TO BEGIN THE
EXTENDED...BUT A RETURN TO WINTER APPEARS LIKELY AS VERY COLD AIR
FLOODS BACK INTO THE REGION FOR MID-TO-LATE WEEK.
COASTAL TROUGH WILL TRY TO ADVECT ONSHORE EARLY TUESDAY ON RETURN
FLOW AROUND A DEPARTING HIGH PRESSURE...BUT THIS WILL MOSTLY WASH
OUT AHEAD OF AN ADVANCING LOW PRESSURE AND COLD FRONT WHICH IS
LIKELY TO CROSS THE AREA BY EARLY WEDNESDAY. THE COMBINATION OF
RETURN SURFACE FLOW AND RENEWED RIDGING ALOFT WILL MAKE TUESDAY A
SLIGHTLY ABOVE NORMAL DAY...ALTHOUGH CLOUD COVER WILL SOMEWHAT
INHIBIT TOTAL WARMING. A WAVE OF LOW PRESSURE ALONG THE ADVANCING
COLD FRONT WILL SKIRT OVER OR JUST NORTH OF THE AREA LATE TUESDAY
AND TUESDAY NIGHT...BRINGING INCREASING RAIN CHANCES FOR A SHORT
PERIOD OF TIME AS PWATS RISE TOWARDS 1 INCH AND THETA-E RIDGE
ADVECTS UP THE COAST. MOS P-NUMBERS ARE ALREADY IN THE LIKELY
CATEGORY...AND WILL BUMP POP TOWARDS HIGH CHANCE FOR TUESDAY NIGHT
AND EARLY WEDNESDAY. AS NOTED BY PREVIOUS FORECASTER...COLD AIR WILL
CHASE THIS MOISTURE INTO WEDNESDAY...AND MAY CREATE A P-TYPE ISSUE
AT THE TAIL END OF THIS PRECIP EVENT. ATTM THIS LOOKS LIKE A VERY
SMALL POSSIBILITY AND WILL LEAVE ALL PRECIP AS LIQUID FOR NOW.
THE STORY BEYOND WEDNESDAY WILL BE RENEWED ARCTIC COLD FOR THE
REMAINDER OF THE EXTENDED. ARCTIC FRONT WILL CRASH THROUGH THIS
AREA...WITH 850MB TEMPS PLUMMETING NEARLY 20C BETWEEN TUESDAY NIGHT
AND THURSDAY MORNING! THE EXACT TIMING OF THIS FRONT IS STILL IN
QUESTION...AS THE ECMWF HAS A FASTER PROGRESSION THAN THE GFS. AS
PROGRESSIVE AS THE PATTERN HAS BEEN...FAVOR THE ECMWF SOLUTION WHICH
WOULD MAKE WED A CHILLY DAY...AND WILL DROP HIGHS SLIGHTLY FROM
INHERITED. STILL...THE CORE OF THE COLD AIR FUNNELS INTO THE AREA BY
THURSDAY IN CONJUNCTION WITH A PIECE OF THE CANADIAN VORTEX DROPPING
INTO NEW ENGLAND. THIS WILL LIKELY BRING TEMPS TO WELL BELOW
MID-WINTER NORMS FOR THU/FRI WITH HIGHS AND LOWS 10-15 DEGREES BELOW
NORMAL.
&&
.AVIATION /09Z SATURDAY THROUGH WEDNESDAY/...
AS OF 06Z...RESIDUAL LOW-LEVEL MOISTURE ALONG THE COAST IS CONFINED
TO A LAYER BARELY 500 FEET THICK...BUT THIS HAS YIELDED LOW STRATUS
CEILINGS AND AREAS OF GROUND FOG ACROSS SE NORTH CAROLINA AND
COASTAL SOUTH CAROLINA. UNTIL NORTHERLY WINDS ARRIVE BETWEEN 08-10Z
AND PUSH THE FOG/LOW CLOUDS OUT TO SEA WE CAN EXPECT FLIGHT CATEGORY
RESTRICTIONS TO CONTINUE. LIFR CONDITIONS ARE EXPECTED AT TIMES. THE
00Z GFS MODEL WAS OF NO HELP...AND EVEN THE 00Z NAM MODEL DOES NOT
SEE THE MOISTURE WELL ENOUGH TO PRODUCE FOG IN ITS PROGS. THE 02Z
HRRR AND RUC MODELS ARE A LITTLE BETTER...AND MY FORECAST FOLLOWS
THE HRRR RATHER CLOSELY THROUGH 10Z.
EXPECT VFR AFTER DAYBREAK WITH NORTHEAST WINDS AOB 10 KTS...BECOMING
LIGHT AND EASTERLY AFTER 00Z SUNDAY.
EXTENDED OUTLOOK...EXPECT VFR CONDITIONS THROUGH MONDAY. MVFR CIGS
AND RAIN POSSIBLE TUESDAY AND WEDNESDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 300 AM SATURDAY...LIGHT WEST WINDS THIS MORNING WILL SHIFT
NORTH-NORTHEASTERLY BEFORE DAYBREAK AS THE FINAL PIECE OF
YESTERDAY`S COLD FRONT FINALLY SWEEPS ACROSS THE AREA. UNTIL THE
FRONT ARRIVES...POCKETS OF MOIST AIR LINGERING ACROSS THE
NEARSHORE WATERS COULD CAUSE LOCALLY REDUCED VISIBILITY IN SEA
FOG. THE FRONT WILL DRIFT OFFSHORE LATER TODAY AS LOW PRESSURE
MOVES NORTHEAST ALONG IT. ASIDE FROM A 6-HOUR PERIOD OF STRONGER
NORTHEAST WINDS (15 KNOTS) THIS MORNING AND SOME CLOUDINESS...MOST
OF THE IMPACTS WITH THE LOW WILL REMAIN FARTHER OFFSHORE. A SECOND
AREA OF WEAK LOW PRESSURE WILL DEVELOP ALONG THE FRONT LATE
TONIGHT...WITH LIGHT NORTHEAST WINDS CONTINUING.
WITH SUCH LIGHT WINDS THIS MORNING THE ONLY WAVES ON THE OCEAN ARE
THOSE PRODUCED BY THE STRONG WINDS YESTERDAY. THIS IS A 7 TO 8
SECOND SOUTHEAST SWELL STILL BEING MEASURED AT THE FRYING PAN SHOALS
BUOY AT 5 FEET. THIS SWELL WILL BE OVERLAID BY A SHORTER PERIOD
NORTHEAST CHOP LATER THIS MORNING...WITH TOTAL SEAS INSIDE 20 MILES
OF SHORE AVERAGING 3-5 FEET TODAY AND 3 FEET TONIGHT.
SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 300 AM SATURDAY...WEAK AND DRY COLD FRONT TO CROSS THE AREA
SUNDAY NIGHT WILL CREATE TWO VASTLY DIFFERENT WIND REGIMES OVER THE
WATERS DURING THE PERIOD. SW WINDS ON SUNDAY AHEAD OF THE COLD FRONT
WILL RISE FROM AROUND 5 KTS...TO 10-15 KTS SUNDAY NIGHT JUST AHEAD
OF THE FROPA. THIS WILL PUSH SEAS UP TO 3-4 FT EARLY MONDAY MORNING.
COLD FRONT LATE SUNDAY NIGHT WILL BE ACCOMPANIED BY A SUDDEN WIND
SHIFT TO THE NORTH MONDAY MORNING AT 10-15 KTS...BEFORE VEERING TO
THE NE AND FALLING TO AROUND 10 KTS LATE. WAVE HEIGHTS WILL REMAIN
AT 3-4 FT ON MONDAY...BUT A CONFUSED SPECTRUM IS LIKELY THE FIRST
HALF OF THE DAY AS NORTHERLY WIND CHOP BEGINS TO DEVELOP OVER THE
RESIDUAL SW WIND WAVES.
LONG TERM /TUESDAY THROUGH WEDNESDAY/...
AS OF 300 AM SATURDAY...BRIEF HIGH PRESSURE WILL MOVE ACROSS THE
WATERS TUESDAY AND WELL OFFSHORE TUESDAY NIGHT AHEAD OF A WAVE OF
LOW PRESSURE AND STRONG COLD FRONT WHICH WILL MOVE OFFSHORE EARLY
WEDNESDAY. THIS CREATES VARIABLE WIND DIRECTIONS ON
TUESDAY...EVENTUALLY BECOMING SW AT 10-15 KTS TUESDAY NIGHT. THE
WAVE OF LOW PRESSURE WILL MOVE NORTH OF THE LOCAL AREA...BUT THE
SUBSEQUENT ARCTIC FRONT WILL CROSS THE WATERS DIRECTLY...WITH GUSTY
NW WINDS DEVELOPING IN ITS WAKE ON WEDNESDAY...RISING TO 20-25 KTS
WED NIGHT BEFORE SLOWLY EASING BY THE END OF THE PERIOD. WAVE
HEIGHTS WILL BE 3-4 FT MUCH OF THE PERIOD...BUT AMPLIFICATION IS
EXPECTED WED NIGHT ON THE STRONGER WINDS WHEN SEAS WILL JUMP TO 4-6
FT...AND A SMALL CRAFT ADVISORY WILL LIKELY BE NEEDED.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...JDW
NEAR TERM...TRA
SHORT TERM...JDW
LONG TERM...JDW
AVIATION...TRA
MARINE...TRA/JDW
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1224 AM EST SAT FEB 22 2014
.SYNOPSIS...
HIGH PRESSURE WILL BRING DRIER AND COOLER AIR INTO THE REGION
OVERNIGHT INTO SATURDAY. THE HIGH WILL MOVE OFFSHORE SUNDAY
FOLLOWED BY A COLD FRONT PASSAGE SUNDAY NIGHT. AN ARCTIC FRONT
WILL OPEN THE DOOR FOR WELL BELOW NORMAL TEMPERATURES TO SPILL
IN FROM CANADA...BEGINNING IN THE MIDDLE OF NEXT WEEK...PERSISTING
INTO NEXT WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
AS OF 1230 AM SATURDAY...THE LEADING EDGE OF THE DRY AIR HAS MADE IT
THROUGH FLORENCE AND DARLINGTON WHERE DEWPOINTS ARE IN THE 30S. THE
STORY IS VERY DIFFERENT TO THE EAST WHERE A VERY SHALLOW LAYER OF
DEWPOINTS IN THE 50S EXTENDING UP TO ONLY 500 FEET AGL HAS YIELDED
FOG AND LOW STRATUS CLOUDS ACROSS LUMBERTON...WILMINGTON AND MYRTLE
BEACH. SYNOPTIC MODELS (GFS AND NAM) ARE OF VERY LITTLE HELP AS THEY
DO NOT SEE THIS SHALLOW AND PRACTICALLY MESOSCALE AREA OF MOISTURE.
THE 02Z HRRR IS THE MODEL OF CHOICE...AS IT AND THE LATEST RUC MODEL
SHOW NORTHERLY WINDS NOT DEVELOPING UNTIL 3-5 AM...SCOURING OUT THE
LOW-LEVEL MOISTURE AND ALLOWING VISIBILITIES/CEILINGS TO FINALLY
IMPROVE. FORECAST LOW TEMPS HAVE BEEN BUMPED UP A LITTLE ALONG THE
COAST AS WELL. PREVIOUS DISCUSSION FROM 900 PM FOLLOWS...
STRONG RUMBLES CONTINUED TO REVERBERATE ACROSS THE GULF STREAM
WATERS THIS EVENING ASSOCIATED WITH A VOLATILE PRE-FRONTAL SQUALL
MAKING CONTINUED EASTWARD PROGRESS. A SOLID LINE OF LIGHTNING
STRIKES ELECTRIFIED AREAS FROM THE ROCKY MAINE BEACHES TO THE MILD
TREASURE COAST OF FLORIDA THIS MID EVENING. CLEARING IS IN THE CARDS
FOR THE CAROLINAS OVERNIGHT ASIDE FROM STREAKING AND THIN CIRRUS
CLOUDS RIDING A RACING SOUTHERN STREAM JET TRACK. AM NOT EXPECTING
SIGNIFICANT IMPACTS ON TEMPERATURES OVERNIGHT DUE TO CLOUDS.
THE ACTUAL COLD FRONT/WIND-SHIFT IS CLEARING OUR FAR INLAND ZONES
AND WILL REACH THE COAST BY OR JUST PRIOR TO MIDNIGHT. WINDS WILL
TEND TO W-NW-N OVERNIGHT BUT POST-FRONTAL WINDS ARE NOT STRONG AND
A STRONG BLUSTERY COLD SURGE IS NOT EXPECTED. TEMPERATURES HOWEVER
WILL BEGIN TO NOTICEABLY COOL AFTER MIDNIGHT...DIPPING IN THE MID
40S AT THE COAST AND UPPER 30S TO NEAR 40 INLAND BY DAYBREAK SAT.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/...
AS OF 300 PM FRIDAY...THE WEEKEND LOOKS MUCH DRIER AND CALMER. HIGH
PRESSURE TO THE WEST WILL BUILD OVERHEAD THROUGH SAT AND RIDGE BACK
ACROSS THE FORECAST AREA INTO SUN MORNING AS IT BEGINS TO MOVE
OFFSHORE. A COLD FRONT WILL MOVE ACROSS THE AREA AND OFFSHORE SUN
NIGHT. A WAVE OF LOW PRESSURE WILL DEVELOP ON THE BOUNDARY AS IT
MOVES OFFSHORE. MOISTURE RETURN LOOKS RATHER MEAGER AHEAD OF THE
FRONT AND WILL KEEP POPS BELOW THRESHOLD AT THIS TIME...HOWEVER...IT
IS POSSIBLE A FEW SHOWERS COULD GRAZE THE COAST SUN NIGHT.
TEMPS THIS PERIOD WILL BE MUCH MORE SEASONABLE. HIGHS WILL BE IN THE
60S SAT AND AROUND 70 ON SUN. THE SEABREEZE ON SUN WILL KEEP HIGHS
AT THE BEACHES IN THE MID 60S. LOWS WILL BE IN THE 40S BOTH
NIGHTS...PERHAPS AROUND 50 AT THE COAST.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 345 PM FRIDAY...MODELS IN GENERAL AGREEMENT IN STARTING OFF
THE LONG TERM PERIOD WITH FAST ZONAL FLOW ALOFT EARLY MONDAY. BY
LATE MONDAY AND FOR THE REMAINDER OF THE LONG TERM PERIOD THRU
FRIDAY...FLOW ALOFT WILL BE IN THE PROCESS OF RE-AMPLIFYING ACROSS
THE FORECAST AREA...TO NEARLY BACK TO WHAT HAS TRANSPIRED THRU-OUT
MUCH OF THIS COLD WINTER SEASON ACROSS THE FORECAST AREA.
MEANING...LONG WAVE TROFFING IN THE MID AND UPPER LEVELS TO AFFECT
THE EASTERN 1/3RD TO 1/2 OF THE U.S. THIS WILL ALSO INCLUDE THE
HUDSON BAY VORTEX DROPPING SOUTHWARD TO THE GREAT LAKES REGION BY
THE MID TO LATE WEEK UPCOMING PERIOD. AT THE SAME TIME...THE
WESTERN 1/3RD OF THE U.S. TO EXPERIENCE AMPLIFIED LONGWAVE UPPER
RIDGING.
MODELS AS USUAL WILL HAVE THEIR TIMING ISSUES WITH ONE ANOTHER IN
REGARD TO THE PASSAGE OF SFC FEATURES DURING THIS UPCOMING LONG
TERM PERIOD. BUT...THEY ALL REMAIN SIMILAR WITH THE EVENTUAL
TRANSITION BACK TO THE WELL BELOW NORMAL COLD WEATHER ACROSS THE
ILM CWA BY THE END OF THIS UPCOMING WEEK. FOR MONDAY AND
TUESDAY...A WEAK COLD FRONT WILL PUSH THRU EARLY IN THE PERIOD
BEFORE STALLING SOUTH OF THE FA B4 NEARLY DISSIPATING BY TUESDAY.
A FEW MODELS KEEP THE FRONTS IDENTITY AND RETURN IT TO THE NORTH
AS A WARM FRONT DURING TUESDAY. OTHERWISE...WEAK RIDGING WILL
AFFECT THE REGION. MAX/MIN MON THRU WED MORNING WILL RUN ABOVE
NORMAL WITH A REMOTE CHANCE OF BREAKING 70 DEGREES FOR HIGHS ON
TUE. DURING WED...THE POLAR/ARCTIC COLD FRONT WILL PUSH ACROSS
THE FA...ALONG WITH A DEVELOPING AND RAPIDLY INTENSIFYING SFC LOW
MOVING ALONG IT. PLENTY OF MOISTURE AND AVAILABLE DYNAMICS
TO WARRANT 30-40 POPS ACROSS THE FA. WILL CONTINUE WITH NO PCPN
TYPE ISSUES WITH THIS PCPN EVENT. HOWEVER...IT BARES WATCHING IF
ENOUGH COLD AIR CAN LEACH IN B4 THE DEEPENING LOW DEPARTS...THEN
PCPN TYPE WILL NEED TO BE RE-VISITED.
MODELS ARE SIMILAR...EVEN THIS FAR OUT IN TIME...WITH BELOW OR
POSSIBLY MUCH BELOW NORMAL MAX/MIN TEMPS FOR THU THRU FRI. HAVE
LOWERED THE PREVIOUS FORECAST TEMPS NEARLY A CATEGORY DURING THIS
TIME PERIOD...BUT NOT AS COLD AS SOME GUIDANCE CURRENTLY
ILLUSTRATES.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
AS OF 06Z...RESIDUAL LOW-LEVEL MOISTURE ALONG THE COAST IS CONFINED
TO A LAYER BARELY 500 FEET THICK...BUT THIS HAS YIELDED LOW STRATUS
CEILINGS AND AREAS OF GROUND FOG ACROSS SE NORTH CAROLINA AND
COASTAL SOUTH CAROLINA. UNTIL NORTHERLY WINDS ARRIVE BETWEEN 08-10Z
AND PUSH THE FOG/LOW CLOUDS OUT TO SEA WE CAN EXPECT FLIGHT CATEGORY
RESTRICTIONS TO CONTINUE. LIFR CONDITIONS ARE EXPECTED AT TIMES. THE
00Z GFS MODEL WAS OF NO HELP...AND EVEN THE 00Z NAM MODEL DOES NOT
SEE THE MOISTURE WELL ENOUGH TO PRODUCE FOG IN ITS PROGS. THE 02Z
HRRR AND RUC MODELS ARE A LITTLE BETTER...AND MY FORECAST FOLLOWS
THE HRRR RATHER CLOSELY THROUGH 10Z.
EXPECT VFR AFTER DAYBREAK WITH NORTHEAST WINDS AOB 10 KTS...BECOMING
LIGHT AND EASTERLY AFTER 00Z SUNDAY.
EXTENDED OUTLOOK...EXPECT VFR CONDITIONS THROUGH MONDAY. MVFR CIGS
AND RAIN POSSIBLE TUESDAY AND WEDNESDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1230 AM SATURDAY...THE SMALL CRAFT ADVISORY HAS BEEN ALLOWED
TO EXPIRE...ALTHOUGH THE STRONG WINDS FROM EARLIER TODAY PRODUCED A
HEALTHY 7-8 SECOND SWELL THAT IS NOW THE DOMINANT WAVE COMPONENT
MEASURED AT THE BUOYS. IT WILL TAKE SOME TIME FOR THIS SWELL TO
DIMINISH...AND 3-5 FOOT SEAS WILL CONTINUE INTO DAYBREAK. THE
BIGGEST CHANCE WITH THIS FORECAST WAS TO ADD FOG INTO THE FORECAST
THROUGH ABOUT 4-5 AM. WEBCAMS FROM CAROLINA BEACH AND SOUTHPORT
INDICATE LOW CLOUDS AND SOME AREAS OF FOG PLAGUING THE COAST EARLY
THIS MORNING. PREVIOUS DISCUSSION FROM 900 PM FOLLOWS...
ADVISORIES TO PREVAIL UNTIL MIDNIGHT AS SEAS RECOVER AND GUSTINESS
ABATES. 4-7 FOOT SEAS AND WEST WINDS OF 15-25 KT SHOULD PREVAIL
THROUGH MOST OF THE EVENING. AN EXERCISE CAUTION HEADLINE MAY BE
NEEDED AFTER MIDNIGHT FOR 5 FOOT SEAS OFFSHORE AND POTENTIAL NNW
WIND GUSTS TO 20 KT. STORMS HAVE MOVED EAST OF THE 0-20NM WATERS AND
OVERALL CLEARING IS EXPECTED FOR THE OVERNIGHT PERIOD WITH IMPROVING
MARINE CONDITIONS. ALL LIGHTNING AND TSTM ACTIVITY WILL REMAIN
CONFINED TO...AND EAST OF THE GULF STREAM WATERS OVERNIGHT.
SHORT TERM /SATURDAY THROUGH SUNDAY
NIGHT/... AS OF 300 PM FRIDAY...WINDS WILL STILL BE FROM THE NE ON
SAT AS HIGH PRESSURE BUILDS ACROSS THE WATERS FROM THE W. AS HIGH
PRESSURE BEGINS TO MOVE OFFSHORE ON SUN...ENE WINDS WILL VEER TO S
AND THEN SW BY DAYS END. THE PASSAGE OF A COLD FRONT WILL SHIFT
WINDS TO THE N OVERNIGHT SUN. NE WINDS WILL STILL BE GUSTY INTO
EARLY SAT AFTERNOON...UP TO 20 KT. THE STRONGEST WINDS THIS PERIOD
ARE EXPECTED IN THE WAKE OF THE COLD FRONT...AND WE WILL BE
NEARING SMALL CRAFT ADVISORY CRITERIA AROUND DAYBREAK MON. SEAS
WILL BE UP TO 4 FT ON SAT AND THEN SUBSIDING TO 3 FT OR LESS SAT
NIGHT AND SUN. SEAS WILL BUILD AGAIN SUN NIGHT...REACHING 5 FT
ACROSS THE OUTER WATERS.
LONG TERM /MONDAY THROUGH WEDNESDAY/...
AS OF 345 PM FRIDAY...WEAK COLD FRONTAL PASSAGE THAT PUSHES THROUGH
EARLY MONDAY TO STALL AND NEARLY DISSIPATE SOUTH OF THE AREA
WATERS DURING THE DAY MONDAY INTO TUE. WEAK SFC RIDGE AXIS TO
EXTEND/AFFECT THE AREA WATERS THRU TUESDAY. THE AXIS WILL EXTEND
FROM THE NW OFF THE MAINLAND IMMEDIATELY AFTER EARLY MONDAYS
FROPA. THEN...FROM THE EAST FROM A WEAK BUBBLE HIGH OFFSHORE FROM
THE CAROLINA COASTS. A FEW MODELS INDICATE THAT THE STALLED
FRONTAL BOUNDARY MAY STILL EXIST TUESDAY...AND PUSH IT BACK TO THE
NORTH AS A WARM FRONT. TO SUM IT UP...MONDAY AND TUESDAY WILL
FEATURE CHANGING/VEERING WIND DIRECTIONS WITH SPEEDS GENERALLY
AROUND 15 KT OR LESS. SIGNIFICANT SEAS MON THRU TUE WILL GENERALLY
HOLD IN THE 2 TO 4 FOOT OR 3 TO 5 FOOT RANGE. ONSHORE FLOW DURING
TUE WILL KEEP SEAS RATHER ACTIVE...NOT TO THE HEIGHT THAT
WAVEWATCH3 CURRENTLY ILLUSTRATES. BY WED...DEEPENING LOW PRESSURE
ALONG THE APPROACHING AND EVENTUAL PASSAGE OF THE POLAR/ARCTIC
COLD FRONT WILL DRIVE RESULTING WINDS AND SIGNIFICANT SEAS TO AT-
LEAST SCA THRESHOLDS. GALE THRESHOLDS DURING WED REMAIN
POSSIBLE...WITH A FEW OF THE MODELS LOOKED AT...HINT AT RAPIDLY
INTENSIFYING THE SFC LOW CLOSER TO THE CAROLINA WATERS DURING THE
DAY WEDNESDAY.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...MJC/TRA
SHORT TERM...RJD
LONG TERM...DCH
AVIATION...BJR/TRA
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
956 PM CST SUN FEB 23 2014
.UPDATE...
ISSUED AT 955 PM CST SUN FEB 23 2014
MAIN CHALLENGE FOR TONIGHT IS INHERITED WIND CHILL HEADLINES.
WARMEST TEMPS AS OF RIGHT NOW ARE OVER SOUTHEASTERN ND...AND
MODELS SHOWING RANSOM/SARGENT HAVING LIGHTEST WINDS TONIGHT AS
WELL (ALREADY AROUND 5KTS). WILL REMOVE THESE TWO COUNTIES FROM
ADVISORY AS WIND CHILLS ARE NOT EXPECTED TO REACH CRITERIA.
FOR THE REST OF THE AREA...WIND CHILLS NEARING CRITERIA WHERE
BREEZY WINDS ARE STILL GOING OVER NORTHEASTERN ND. EXPECT APPARENT
TEMPS IN THIS AREA TO WARM UP A BIT AS WINDS DIE DOWN...THEN BEGIN
FALLING AGAIN IN THE 06Z TO 09Z TIMEFRAME ALONG WITH THE REST OF
THE CWA. DELAYED COUNTIES OUTSIDE OF NORTHEASTER ND/NORTHERN RRV
UNTIL 12 AM BUT 3 AM IS THE MORE LIKELY TIMEFRAME FOR MEETING
ADVISORY CRITERIA. THIS WILL MATCH UP NICELY WITH NEIGHBORING WFOS
TO THE EAST AND SOUTH. NO OTHER CHANGES MADE TO THIS FCST.
FOR TOMORROW...THE LATEST NAM AND RUC CONTINUE TO BRING PRECIP
INTO THE SOUTHWESTERN ZONES AFTER NOON TIMEFRAME...WITH THE RUC
HAVING DRIER QPFS. LOOKS LIKE MOST SNOW SHOULD BE SOUTH OF THE HWY
200 CORRIDOR OR PERHAPS EVEN THE I 94 CORRIDOR. NO CHANGES TO POPS MADE.
UPDATE ISSUED AT 656 PM CST SUN FEB 23 2014
CLEAR SKIES ACROSS CWA TONIGHT...WITH WINDS STILL IN THE 15 TO 25
MPH RANGE FOR MUCH OF THE AREA. OVER THE NEXT COUPLE OF
HOURS...WINDS SHOULD BEGIN TO DIE OFF ENOUGH TO ALLOW TEMPS TO
BEGIN TO FALL YET HIGH ENOUGH TO BRING WIND CHILLS IN THE 25 BELOW
TO 35 BELOW RANGE. NO PLANNED CHANGES TO HEADLINES TONIGHT.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 325 PM CST SUN FEB 23 2014
CHALLENGES INCLUDE WIND CHILLS TONIGHT AND LOW PRECIPITATION
CHANCES TOMORROW. GLOBAL MODELS ARE IN GOOD AGREEMENT AND WILL USE
A BLENDED SOLUTION.
FOR TONIGHT...SCT-BKN CLOUD COVER WILL REMAIN CONFINED TO THE
NORTHEAST FORECAST AREA AS CLOUD DECK AROUND JAMES BAY LOW
CONTINUES TO PIVOT TO THE SOUTH. ALL OTHER AREAS WILL REMAIN
MOSTLY CLEAR AS SURFACE RIDGE BUILDS ACROSS EASTERN ND INTO
SOUTHWEST MN. CURRENT TEMPERATURES UNDER THIS RIDGE ARE IN THE
SINGLE DIGITS BELOW ZERO ACROSS ALBERTA AND SOUTHERN SASKATCHEWAN
AND THIS COLDER AIR MASS WILL BEGIN TO SAG SOUTHWARD OVERNIGHT.
NORTHWEST WIND WILL REMAIN ELEVATED BETWEEN 5 AND 10 MPH...BUT
TEMPERATURE GUIDANCE IN FAIR AGREEMENT SHOWING OVERNIGHT LOWS
DROPPING INTO THE LOW TEENS BELOW ZERO. AIR TEMPERATURES AND WINDS
WILL RESULT IN WIND CHILL VALUES FROM 25 TO 35 BELOW...SO WILL
ISSUE A CWA-WIDE WIND CHILL ADVISORY FROM 04 UTC TONIGHT UNTIL 16
UTC MONDAY.
SURFACE LOW WILL DIVE SOUTH ALONG THE LEE OF THE ROCKIES ON MONDAY
WITH WARM AIR ADVECTION SNOW DEVELOPING MAINLY ACROSS SD. NORTHERN
EXTENT OF THIS SNOW SHIELD MAY CLIP THE SOUTHERN FORECAST AREA...
SO WILL KEEP CHANCE POPS MAINLY ALONG AND SOUTH OF THE I-94/HWY 10
CORRIDOR. WAS ABLE TO REMOVE POPS MONDAY MORNING WITH SLOWER
FORWARD PROGRESSION IN THE MODELS. ANY ACCUMULATION WILL BE
MINIMAL...AROUND A HALF INCH OR LESS. TEMPERATURES TO BE A BIT
COOLER THAN TODAY...BUT STILL ABOVE ZERO WITH NORTHWEST WIND
BETWEEN 5 AND 15 MPH.
LINGERING SNOW SHOWERS POSSIBLE ACROSS SOUTHEAST FORECAST AREA
MONDAY NIGHT...WITH ALL OTHER AREAS DRY. MOSTLY CLEAR SKIES...
TEMPERATURES BELOW ZERO AND WIND AROUND 10 MPH WILL LIKELY
NECESSITATE ANOTHER WIND CHILL ADVISORY.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 325 PM CST SUN FEB 23 2014
MORE OF THE SAME FOR TUESDAY AND WEDNESDAY AS 1035 TO 1040 HPA
SURFACE HIGH DROPS SOUTH FROM CANADA AND MOVES ACROSS THE NORTHERN
PLAINS. EXPECT MORE SUN THAN CLOUDS WITH PERSISTENT BREEZY
CONDITIONS FROM THE WEST-NORTHWEST. HIGH TEMPERATURES TUESDAY
AROUND THE ZERO MARK WILL WARM SLIGHTLY BY WEDNESDAY INTO THE
SINGLE DIGITS TO MID TEENS ABOVE ZERO. THE SEEMINGLY ENDLESS
STREAM OF WIND CHILL ADVISORIES WILL MOST LIKELY CONTINUE BOTH
TUESDAY AND WEDNESDAY NIGHT.
LONG RANGE MODELS CONTINUE TO ADVERTISE THE COLD POOL OF AIR SITTING
OVER CENTRAL CANADA INTO HUDSON BAY REGION DOWN INTO THE NORTH
CENTRAL UNITED STATES. SURFACE HIGH REMAINS FROM NORTH DAKOTA
INTO SASK. THUS FOR THE THURSDAY THROUGH SUNDAY PERIOD EXPECTING
WELL BELOW NORMAL TEMPERATURES BUT DRY CONDITIONS. MAY BE A LITTLE
LOW ON THURSDAY FEATURING RIDICULOUSLY COLD MAX TEMPS BUT LET RIDE
FOR NOW. ADDED A COUPLE OF DEGREES TO WEEKEND TEMPS...IF ECMWF IS
CORRECT IT WILL BE COLDER THOUGH AS IT ROTATES COLD POOL FROM
NORTHERN MANITOBA THROUGH WINNIPEG INTO MINNESOTA. FORECAST STILL
BARREN WITH RESPECT TO PRECIPITATION THROUGH SATURDAY WITH A SOUTH
TRACKING SYSTEM OFFERING SCANT POPS ACROSS THE FAR SOUTHWEST
BRIEFLY ON SUNDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 656 PM CST SUN FEB 23 2014
CLEAR SKIES ACROSS AREA WITH NORTHWEST WINDS SUBSIDING TONIGHT.
SHOULD SEE LOW VFR TO MVFR CIGS MOVE INTO SOUTHEASTERN ND BY END
OF 00Z TAF FRAMES...WITH SNOW POSSIBLE AT FAR BUT TOO EARLY TO
MENTION IN TAFS ESPECIALLY SINCE EVEN FAR COULD BE ON NORTHERN
EDGE OF PRECIPITATION.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...WIND CHILL ADVISORY UNTIL 10 AM CST MONDAY FOR NDZ038-039-053.
WIND CHILL ADVISORY UNTIL 10 AM CST MONDAY FOR NDZ006>008-
014>016-024-026>030-054.
MN...WIND CHILL ADVISORY UNTIL 10 AM CST MONDAY FOR MNZ003-005-006-
008-009-013>017-022>024-027>032-040.
WIND CHILL ADVISORY UNTIL 10 AM CST MONDAY FOR MNZ001-002-004-
007.
&&
$$
UPDATE...SPEICHER
SHORT TERM...ROGERS
LONG TERM...ROGERS/WJB
AVIATION...SPEICHER
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
944 AM CST SAT FEB 22 2014
.UPDATE...
ISSUED AT 944 AM CST SAT FEB 22 2014
TEMPERATURE CURVE STILL LOOKS GOOD ATTM AND CONTINUE TO SEE WIND
CHILL VALUES INCREASE TO ABOVE CRITERIA...SO WILL EXPIRE THE WIND
CHILL ADVISORY AS PLANNED. OTHERWISE...REST OF FORECAST ON TARGET.
UPDATE ISSUED AT 643 AM CST SAT FEB 22 2014
WIND CHILLS ARE LOWEST THIS MORNING IN THE DEVILS LAKE BASIN AT
AROUND -30...WITH VALUES APPROACHING -25 ACROSS MUCH OF THE REST
OF THE CURRENT ADVISORY. WILL NOT MAKE ANY CHANGES TO THE ADVISORY
FOR THIS UPDATE AND THE REST OF THE FORECAST IS ON TRACK.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 305 AM CST SAT FEB 22 2014
A QUIET PERIOD IS EXPECTED THROUGH THE WEEKEND...WITH TEMPS/CLOUDS THE
MAIN SHORT TERM FOCUS...FOLLOWED BY LIGHT SNOW POTENTIAL ON
MONDAY.
08Z WATER VAPOR IMAGERY REVEALED CONTINUED NORTHWESTERLY FLOW INTO
THE NORTHERN PLAINS UPSTREAM FROM THE DEEP STACKED LOW PRESSURE
SYSTEM NORTH OF LAKE SUPERIOR. THE BAND OF CLOUD COVER EXTENDING
INTO THE NORTHEAST PORTION OF THE FORECAST AREA HAS SLOWLY SHIFTED
NORTHEAST DURING THE OVERNIGHT HOURS WITH SOME LIGHT SNOW
CONTINUING TOWARDS BAUDETTE. SO FAR...WIND CHILLS HAVE STRUGGLED
TO DROP DOWN TO CRITERIA...EXCEPT FOR A FEW SPOTS IN THE DEVILS
LAKE BASIN...BUT STILL EXPECT MORE LOCALES TO APPROACH -25 WIND
CHILLS INTO THE EARLY MORNING HOURS.
FOR TODAY...TEMPS SHOULD BE QUITE SIMILAR TO YESTERDAY WITH
COMPARABLE 925 MB TEMPS AROUND -15C. THUS...HIGHS IN THE SINGLE
DIGITS...TO PERHAPS LOW TEENS IN THE SOUTHWESTERN FORECAST
AREA...ARE EXPECTED. WINDS WILL AGAIN BE BREEZY...WITH A DECENT
PRESSURE GRADIENT REMAINING BETWEEN THE SFC LOW TO THE NORTHEAST
AND HIGH PRESSURE CENTERED OVER WESTERN CANADA. WITH MIXING TO
ABOUT 950 MB OR A BIT ABOVE...WINDS MAY GUST TO 30 MPH...ESPECIALLY
ACROSS THE NORTH. DID KEEP MENTION OF FLURRIES UP TOWARDS LAKE OF
THE WOODS WITH MORE SUN TO THE SOUTHWEST.
TONIGHT...THE 1045 MB SFC HIGH OVER ALBERTA NOSES INTO THE FORECAST
AREA. HOWEVER...WITH WINDS REMAINING UP AROUND 10 KTS...DO NOT
EXPECT A RAPID TEMP DROP...WITH LOWS SIMILAR TO THE PAST FEW NIGHTS
IN THE NEGATIVE SINGLE DIGITS. CLOUD COVER COULD AFFECT TEMPS...WITH
THE MOST LIKELY AREA TO HAVE SOME CLOUDS TOWARDS LAKE OF THE WOODS.
HOWEVER...SOME GUIDANCE TRIES TO DROP CLOUD COVER CURRENTLY OVER
SASKATCHEWAN INTO PARTS OF THE AREA LATER TODAY AND OVERNIGHT.
BASED ON CURRENT FORECAST TEMPS/WINDS...WIND CHILLS MAY APPROACH
THE -25 WIND CHILL CRITERIA THRESHOLD FOR A FEW HOURS...COMPARABLE
TO PREVIOUS NIGHTS. DID NOT KEEP ANY PRECIP MENTION OVER THE LAKE
OF THE WOODS AREA...BUT A FEW FLURRIES ARE POSSIBLE UNDER ANY
LOWER CLOUD DECK.
SUNDAY SHOULD BE VERY SIMILAR TO SATURDAY...WITH CHILLY TEMPS IN THE
SINGLE DIGITS TO LOW TEENS AND BRISK WEST TO NORTHWEST WINDS...AS
WEAK LOW-LEVEL COLD ADVECTION CONTINUES AND 925 MB WINDS REMAIN IN
THE 25-30 KT RANGE. MORE CLOUDS SHOULD LINGER OVER THE FAR
NORTHEAST...WITH PERHAPS A FLURRY OR TWO.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 305 AM CST SAT FEB 22 2014
BY SUNDAY NIGHT AND MONDAY...A 500 MB SHORTWAVE TROUGH WILL APPROACH
FROM THE NORTHWEST. MODELS OVERALL ARE IN DECENT AGREEMENT...WITH
SOME PLACEMENT DIFFERENCES. THE 00Z ECMWF IS A BIT FARTHER NORTH
WITH THE WAVE COMPARED WITH THE GEM/GFS. A BAND OF LIGHT SNOW
ASSOCIATED WITH THE MID-LEVEL FRONTOGENESIS WILL MOVE
SOUTHEASTWARD ACROSS THE NORTHERN PLAINS ON MONDAY...AIDING BY AN
APPROACHING 300 MB JET STREAK. THE 00Z NAM KEEPS THIS BAND PRIMARILY
SOUTH OF THE REGION...WHILE THE ECMWF IS FARTHEST NORTH...AND
WOULD BRING SOME LIGHT SNOW TO MUCH OF THE REGION. GIVEN THIS
UNCERTAINTY...KEPT POPS SIMILAR TO THE PREVIOUS FORECAST...WITH
THE HIGHEST POPS CLOSEST TO THE SD BORDER. HOWEVER...THE SYSTEM
WON/T HAVE MUCH MOISTURE TO WORK WITH...SO ACCUMULATIONS WOULD BE
MINOR.
LOWS ON SUNDAY NIGHT COULD BE A BIT COLDER...WITH LIGHTER WINDS.
HIGHS ON MONDAY ALSO SHOULD BE A FEW DEGREES COLDER...ESPECIALLY
ACROSS THE NORTH...AS 925 MB TEMPS TO NEAR -20C WORK INTO THE
DEVILS LAKE BASIN AND NORTHERN VALLEY BEHIND THE SHORTWAVE.
FOR NOW WENT WITH A DRY FORECAST MONDAY NIGHT...ALTHOUGH THE ECMWF
AND GEM DO HOLD ONTO LIGHT SNOW INTO THE EVENING ACROSS WEST-CENTRAL
MN. OTHERWISE...COLD HIGH PRESSURE WILL BEGIN TO APPROACH FROM THE
WEST...WITH TEMPS FALLING INTO THE NEGATIVE TEENS. CONTINUING WITH
THE THEME THIS WINTER...WIND CHILLS WILL REMAIN A CONCERN BOTH ON
SUNDAY NIGHT AND MONDAY NIGHT.
FOR TUESDAY THROUGH SATURDAY...THE 00Z EURO REMAINS IN GOOD
AGREEMENT WITH PAST RUNS AND GENERALLY COLDER THAN THE 00Z GFS. ALL
HAVE AREA IN NORTH-NORTHWEST FLOW. ONE SHORT WAVE MOVES THRU EARLY
TUESDAY FOLLOWED BY COLD HIGH PRESSURE DROPPING THRU SASK INTO THE
WESTERN DAKOTAS. ANOTHER COLD FRONT DROPS THRU LATER WED WITH
ANOTHER HIGH BEHIND IT AS TEMPERATURES REMAIN SIGNIFICANTLY BELOW
NORMAL. EXPECT DRY WEATHER THRU FRIDAY. VERY LATE IN THE EXTENDED
THERE IS SOME AGREEMENT AMONG THE EURO/GFS FOR A LOW TO DEVELOP OVER
THE CENTRAL ROCKIES AND MOVE EAST. GFS REMAINS MUCH MORE BULLISH
WITH PRECIP IN SRN ND/SD/MN VERSUS A BIT LESS WET EURO. IT IS NOTED
THOUGHT THAT THE 00Z GEM AS HIGH OVER NORTH DAKOTA NEXT SATURDAY
WITH PRECIP SOUTH OF OUR AREA.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 643 AM CST SAT FEB 22 2014
CLOUD SHIELD ON THE WESTERN PERIPHERY OF THE UPPER LOW WEST OF
HUDSON BAY WILL AFFECT PRIMARILY KTVF AND KBJI TODAY INTO TONIGHT.
KBJI HAS BEEN IN THE MVFR RANGE EARLY THIS MORNING...AND THE RAP IS
MAINTAINING THESE LOW CIGS MUCH OF THE DAY. WENT A BIT MORE
OPTIMISTIC WITH VFR CIGS THIS AFTERNOON AT KBJI...BUT CONFIDENCE IS
LOW. OTHERWISE...SOME MID/HIGH CLOUDS WILL APPROACH FROM THE NORTH
AND WEST TODAY...WITH WINDS AGAIN BREEZY FROM THE
NORTHWEST...GUSTING OVER 20 KTS AT TIMES DURING THE DAY.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...WIND CHILL ADVISORY UNTIL 10 AM CST THIS MORNING FOR NDZ006>008-
014>016-024-026>030-038-039-054.
MN...WIND CHILL ADVISORY UNTIL 10 AM CST THIS MORNING FOR MNZ001>004-
007-008-013>016-022-023-027>031.
&&
$$
UPDATE...HOPKINS
SHORT TERM...MAKOWSKI
LONG TERM...MAKOWSKI/RIDDLE
AVIATION...MAKOWSKI
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
643 AM CST SAT FEB 22 2014
.UPDATE...
ISSUED AT 643 AM CST SAT FEB 22 2014
WIND CHILLS ARE LOWEST THIS MORNING IN THE DEVILS LAKE BASIN AT
AROUND -30...WITH VALUES APPROACHING -25 ACROSS MUCH OF THE REST
OF THE CURRENT ADVISORY. WILL NOT MAKE ANY CHANGES TO THE ADVISORY
FOR THIS UPDATE AND THE REST OF THE FORECAST IS ON TRACK.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 305 AM CST SAT FEB 22 2014
A QUIET PERIOD IS EXPECTED THROUGH THE WEEKEND...WITH TEMPS/CLOUDS THE
MAIN SHORT TERM FOCUS...FOLLOWED BY LIGHT SNOW POTENTIAL ON
MONDAY.
08Z WATER VAPOR IMAGERY REVEALED CONTINUED NORTHWESTERLY FLOW INTO
THE NORTHERN PLAINS UPSTREAM FROM THE DEEP STACKED LOW PRESSURE
SYSTEM NORTH OF LAKE SUPERIOR. THE BAND OF CLOUD COVER EXTENDING
INTO THE NORTHEAST PORTION OF THE FORECAST AREA HAS SLOWLY SHIFTED
NORTHEAST DURING THE OVERNIGHT HOURS WITH SOME LIGHT SNOW
CONTINUING TOWARDS BAUDETTE. SO FAR...WIND CHILLS HAVE STRUGGLED
TO DROP DOWN TO CRITERIA...EXCEPT FOR A FEW SPOTS IN THE DEVILS
LAKE BASIN...BUT STILL EXPECT MORE LOCALES TO APPROACH -25 WIND
CHILLS INTO THE EARLY MORNING HOURS.
FOR TODAY...TEMPS SHOULD BE QUITE SIMILAR TO YESTERDAY WITH
COMPARABLE 925 MB TEMPS AROUND -15C. THUS...HIGHS IN THE SINGLE
DIGITS...TO PERHAPS LOW TEENS IN THE SOUTHWESTERN FORECAST
AREA...ARE EXPECTED. WINDS WILL AGAIN BE BREEZY...WITH A DECENT
PRESSURE GRADIENT REMAINING BETWEEN THE SFC LOW TO THE NORTHEAST
AND HIGH PRESSURE CENTERED OVER WESTERN CANADA. WITH MIXING TO
ABOUT 950 MB OR A BIT ABOVE...WINDS MAY GUST TO 30 MPH...ESPECIALLY
ACROSS THE NORTH. DID KEEP MENTION OF FLURRIES UP TOWARDS LAKE OF
THE WOODS WITH MORE SUN TO THE SOUTHWEST.
TONIGHT...THE 1045 MB SFC HIGH OVER ALBERTA NOSES INTO THE FORECAST
AREA. HOWEVER...WITH WINDS REMAINING UP AROUND 10 KTS...DO NOT
EXPECT A RAPID TEMP DROP...WITH LOWS SIMILAR TO THE PAST FEW NIGHTS
IN THE NEGATIVE SINGLE DIGITS. CLOUD COVER COULD AFFECT TEMPS...WITH
THE MOST LIKELY AREA TO HAVE SOME CLOUDS TOWARDS LAKE OF THE WOODS.
HOWEVER...SOME GUIDANCE TRIES TO DROP CLOUD COVER CURRENTLY OVER
SASKATCHEWAN INTO PARTS OF THE AREA LATER TODAY AND OVERNIGHT.
BASED ON CURRENT FORECAST TEMPS/WINDS...WIND CHILLS MAY APPROACH
THE -25 WIND CHILL CRITERIA THRESHOLD FOR A FEW HOURS...COMPARABLE
TO PREVIOUS NIGHTS. DID NOT KEEP ANY PRECIP MENTION OVER THE LAKE
OF THE WOODS AREA...BUT A FEW FLURRIES ARE POSSIBLE UNDER ANY
LOWER CLOUD DECK.
SUNDAY SHOULD BE VERY SIMILAR TO SATURDAY...WITH CHILLY TEMPS IN THE
SINGLE DIGITS TO LOW TEENS AND BRISK WEST TO NORTHWEST WINDS...AS
WEAK LOW-LEVEL COLD ADVECTION CONTINUES AND 925 MB WINDS REMAIN IN
THE 25-30 KT RANGE. MORE CLOUDS SHOULD LINGER OVER THE FAR
NORTHEAST...WITH PERHAPS A FLURRY OR TWO.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 305 AM CST SAT FEB 22 2014
BY SUNDAY NIGHT AND MONDAY...A 500 MB SHORTWAVE TROUGH WILL APPROACH
FROM THE NORTHWEST. MODELS OVERALL ARE IN DECENT AGREEMENT...WITH
SOME PLACEMENT DIFFERENCES. THE 00Z ECMWF IS A BIT FARTHER NORTH
WITH THE WAVE COMPARED WITH THE GEM/GFS. A BAND OF LIGHT SNOW
ASSOCIATED WITH THE MID-LEVEL FRONTOGENESIS WILL MOVE
SOUTHEASTWARD ACROSS THE NORTHERN PLAINS ON MONDAY...AIDING BY AN
APPROACHING 300 MB JET STREAK. THE 00Z NAM KEEPS THIS BAND PRIMARILY
SOUTH OF THE REGION...WHILE THE ECMWF IS FARTHEST NORTH...AND
WOULD BRING SOME LIGHT SNOW TO MUCH OF THE REGION. GIVEN THIS
UNCERTAINTY...KEPT POPS SIMILAR TO THE PREVIOUS FORECAST...WITH
THE HIGHEST POPS CLOSEST TO THE SD BORDER. HOWEVER...THE SYSTEM
WON/T HAVE MUCH MOISTURE TO WORK WITH...SO ACCUMULATIONS WOULD BE
MINOR.
LOWS ON SUNDAY NIGHT COULD BE A BIT COLDER...WITH LIGHTER WINDS.
HIGHS ON MONDAY ALSO SHOULD BE A FEW DEGREES COLDER...ESPECIALLY
ACROSS THE NORTH...AS 925 MB TEMPS TO NEAR -20C WORK INTO THE
DEVILS LAKE BASIN AND NORTHERN VALLEY BEHIND THE SHORTWAVE.
FOR NOW WENT WITH A DRY FORECAST MONDAY NIGHT...ALTHOUGH THE ECMWF
AND GEM DO HOLD ONTO LIGHT SNOW INTO THE EVENING ACROSS WEST-CENTRAL
MN. OTHERWISE...COLD HIGH PRESSURE WILL BEGIN TO APPROACH FROM THE
WEST...WITH TEMPS FALLING INTO THE NEGATIVE TEENS. CONTINUING WITH
THE THEME THIS WINTER...WIND CHILLS WILL REMAIN A CONCERN BOTH ON
SUNDAY NIGHT AND MONDAY NIGHT.
FOR TUESDAY THROUGH SATURDAY...THE 00Z EURO REMAINS IN GOOD
AGREEMENT WITH PAST RUNS AND GENERALLY COLDER THAN THE 00Z GFS. ALL
HAVE AREA IN NORTH-NORTHWEST FLOW. ONE SHORT WAVE MOVES THRU EARLY
TUESDAY FOLLOWED BY COLD HIGH PRESSURE DROPPING THRU SASK INTO THE
WESTERN DAKOTAS. ANOTHER COLD FRONT DROPS THRU LATER WED WITH
ANOTHER HIGH BEHIND IT AS TEMPERATURES REMAIN SIGNIFICANTLY BELOW
NORMAL. EXPECT DRY WEATHER THRU FRIDAY. VERY LATE IN THE EXTENDED
THERE IS SOME AGREEMENT AMONG THE EURO/GFS FOR A LOW TO DEVELOP OVER
THE CENTRAL ROCKIES AND MOVE EAST. GFS REMAINS MUCH MORE BULLISH
WITH PRECIP IN SRN ND/SD/MN VERSUS A BIT LESS WET EURO. IT IS NOTED
THOUGHT THAT THE 00Z GEM AS HIGH OVER NORTH DAKOTA NEXT SATURDAY
WITH PRECIP SOUTH OF OUR AREA.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 643 AM CST SAT FEB 22 2014
CLOUD SHIELD ON THE WESTERN PERIPHERY OF THE UPPER LOW WEST OF
HUDSON BAY WILL AFFECT PRIMARILY KTVF AND KBJI TODAY INTO TONIGHT.
KBJI HAS BEEN IN THE MVFR RANGE EARLY THIS MORNING...AND THE RAP IS
MAINTAINING THESE LOW CIGS MUCH OF THE DAY. WENT A BIT MORE
OPTIMISTIC WITH VFR CIGS THIS AFTERNOON AT KBJI...BUT CONFIDENCE IS
LOW. OTHERWISE...SOME MID/HIGH CLOUDS WILL APPROACH FROM THE NORTH
AND WEST TODAY...WITH WINDS AGAIN BREEZY FROM THE
NORTHWEST...GUSTING OVER 20 KTS AT TIMES DURING THE DAY.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...WIND CHILL ADVISORY UNTIL 10 AM CST THIS MORNING FOR NDZ006>008-
014>016-024-026>030-038-039-054.
MN...WIND CHILL ADVISORY UNTIL 10 AM CST THIS MORNING FOR MNZ001>004-
007-008-013>016-022-023-027>031.
&&
$$
UPDATE...MAKOWSKI
SHORT TERM...MAKOWSKI
LONG TERM...MAKOWSKI/RIDDLE
AVIATION...MAKOWSKI
YOU CAN SEE AN ILLUSTRATED VERSION OF THE FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1100 AM CST SAT FEB 22 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 232 AM CST SAT FEB 22 2014
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED NORTHWEST FLOW FROM EASTERN ALASKA INTO THE CENTRAL PLAINS...
AND THURSDAYS WINTER STORM AS A LARGE UPPER LOW OVER FAR NORTHERN
ONTARIO. THE FORECAST AREA CONTINUES TO BE INFLUENCED BY THE
CIRCULATION AROUND THE LARGE UPPER LOW WITH A SERIES OF WEAK
SHORTWAVES ROTATING AROUND IT MOVING THROUGH THE FORECAST AREA.
PLENTY OF DRY AIR SEEN ON THE 00Z MPX SOUNDING HAS KEPT THESE
SHORTWAVES FROM PRODUCING ANYTHING. IN FACT...OUTSIDE OF SOME LOW
STRATUS NORTH OF HIGHWAY 10 IN WISCONSIN...SKIES ARE MOSTLY CLEAR.
LOW TO MID LEVEL NORTHWEST WINDS AROUND THE LOWS CIRCULATION
CONTINUE TO DRAW COLDER AIR SOUTH OUT OF CENTRAL CANADA INTO THE
FORECAST AREA. 850MB TEMPS AT MPX DROPPED FROM -4C AT 00Z FRIDAY
TO -13C AT 00Z SATURDAY. WELL OFF TO THE NORTHWEST...THERE ARE TWO
IMPORTANT SHORTWAVES OF NOTE WHICH INFLUENCE MONDAYS FORECAST...ONE
OVER NORTHERN ALBERTA AND A SECOND IN THE YUKON.
VERY LITTLE CHANGE IN THE UPPER LEVEL PATTERN IS PROGGED OVER THE
NEXT 24 HOURS. THIS MEANS THE FORECAST AREA WILL CONTINUE TO BE
INFLUENCED BY THE CIRCULATION AROUND THE UPPER AND SURFACE LOWS IN
FAR NORTHERN ONTARIO...ALLOWING A FEED OF DRY...COLD AIR ON
NORTHWEST WINDS TO CONTINUE. MAY HAVE TO KEEP A WATCH FOR SOME
FLURRIES THIS MORNING ACROSS NORTHEAST IOWA AND FAR SOUTHWEST
WI...ASSOCIATED WITH A SHORTWAVE TRACKING FROM SOUTH DAKOTA INTO
NORTHERN ILLINOIS. CURRENTLY THINK THE DRY AIR WILL WIN OUT AND ANY
MEANINGFUL SNOW/FLURRIES WILL STAY TO THE SOUTH.
925MB TEMP PROGS SUGGEST THAT THE HIGHER SUN ANGLE HERE IN LATE
FEBRUARY WILL HELP TO MODIFY SOME OF THE COLD AIR DURING THE DAYTIME
HOURS. STILL...READINGS AT 18Z OF -12 TO -14C AND FRESH SNOW ONLY
SUPPORT HIGHS IN THE MID TEENS TO MID 20S. 925MB WINDS STAYING UP
TONIGHT...ON THE ORDER OF 30 TO 35 KT...WILL HELP KEEP SURFACE WINDS
FROM DECOUPLING. HOWEVER...THESE WINDS DROP TEMPS TO -14 TO -18C BY
12Z SUNDAY. THIS COLDER AIR WILL EASILY ALLOW FOR LOWS IN THE SINGLE
DIGITS ABOVE ZERO...AND EVEN IN THE SINGLE DIGITS BELOW ZERO IN THE
TYPICAL COLD SPOTS. WIND CHILLS COULD GET CLOSE ENOUGH TO WARRANT A
WIND CHILL ADVISORY OVER TAYLOR/CLARK COUNTIES LATE TONIGHT INTO
SUNDAY MORNING. GIVEN WIND CHILLS CURRENTLY FORECAST IN THE 18 TO 23
BELOW ZERO RANGE FOR THAT AREA...WILL LET LATER SHIFTS TO DECIDE ON
THE ADVISORY.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 232 AM CST SAT FEB 22 2014
THE RETURN OF ARCTIC AIR REMAINS THE BIG IMPACT ITEM IN THE LONG
TERM...WITH A BRIEF BOUT OF SNOW POSSIBLE MONDAY INTO MONDAY NIGHT.
MODELS CONTINUE TO ADVERTISE THE CURRENT RIDGE OVER THE EASTERN
PACIFIC INTO ALASKA WILL DEVELOP INTO AN OMEGA BLOCK OVER THE NEXT
FEW DAYS...WITH ONLY A SLIGHT MOVEMENT EASTWARD. THIS OMEGA BLOCK
ALLOWS SHORTWAVES OVER THE ARCTIC TO DIVE SOUTH INTO THE NORTHERN
U.S....BRINGING THE ARCTIC AIR WITH THEM. ITS WORTH NOTING THAT
HIGHS OBSERVED ON FRIDAY ACROSS THE NORTHWEST TERRITORIES AND
NUNAVUT REGION WERE IN THE TEENS AND 20S BELOW ZERO. HEADING INTO
LATE NEXT WEEK AND NEXT WEEKEND...A CONSISTENT SIGNAL EXISTS THAT
THE SOUTHERN END OF THE OMEGA BLOCK WILL BREAK DOWN. FOR NOW IT
APPEARS WE WILL STAY INFLUENCED BY TROUGHING AND ARCTIC AIR ACROSS
SOUTHERN CANADA.
THE MAJORITY OF THE SHORTWAVES DROPPING OUT OF THE ARCTIC ARE
SUGGESTED TO HAVE LITTLE IF ANY MOISTURE WITH THEM. THUS...THERE IS
NOT A LOT OF PRECIPITATION FORECAST IN THE LONG TERM. THE LONE
EXCEPTION TO THIS IS ON MONDAY...WHEN THE SHORTWAVES OVER NORTHERN
ALBERTA AND THE YUKON ARE PROGGED TO COME ACROSS THE FORECAST AREA
AS A PHASED SHORTWAVE TROUGH. PRECIPITABLE WATER VALUES ACCORDING
TO THE 22.00Z GFS ARE SUGGESTED TO CLIMB TO 0.20 INCHES...WHICH
COMBINED WITH THE POTENT LOOK OF THE SHORTWAVES SHOULD SQUEEZE OUT
SOME SNOW. THE 22.00Z NAM WAS THE DRIEST OF GUIDANCE...BUT THE WORRY
POSED BY THE MODEL SUGGESTING A DRY SCENARIO KEPT CHANCES FROM GOING
MUCH ABOVE 50. IF IT COMES AROUND TOWARDS A WETTER SCENARIO...
CHANCES CAN BE RAISED. TIMING WISE...MODELS HAVE SLOWED THE
PROGRESSION OF THE SNOW. CONSENSUS SEEMS TO FAVOR SNOW MOVING INTO
LOCATIONS WEST OF THE MISSISSIPPI RIVER DURING THE AFTERNOON...THEN
MARCHING EAST ACROSS THE REST OF THE AREA DURING THE EVENING. AFTER
06Z TUESDAY...MUCH OF THE SNOW LOOKS TO BE OVERWITH. LACK OF
MOISTURE WILL KEEP SNOW AMOUNTS DOWN...BUT WITH SNOW TO WATER RATIOS
NEAR 20 TO 1 SHOULD HELP IN ACCUMULATING ANYWHERE FROM 0.5 TO 2
INCHES OF SNOWFALL.
NOW REGARDING THE COLD. SUNDAY AND MONDAY LOOK PRETTY SIMILAR TO
TODAY WITH REGARDS TO HIGHS...WITH JUST A SLIGHT COOLING EACH DAY AS
COLDER AIR FILTERS IN. A MORE SIGNIFICANT PUSH OF ARCTIC AIR COMES
INTO THE FORECAST AREA TUESDAY INTO TUESDAY NIGHT. IN FACT...925MB
TEMPS FALL FROM -14 TO -18C AT 12Z TUESDAY TO -22 TO -25C BY 12Z
WEDNESDAY. THESE REMAIN PRETTY CONSISTENT...AND IT COMES WITH A
20-40 KT 925MB WIND TOO...SUGGESTING A WIND CHILL ADVISORY IS HIGHLY
LIKELY. A PERIOD OF WARM ADVECTION REMAINS ON TAP TO COME IN ON
WEDNESDAY...THOUGH COUNTER-ACTED FROM A WIND CHILL PERSPECTIVE
BECAUSE OF A BRISK WEST WIND. BEYOND WEDNESDAY...THERE REMAINS SIGNS
OF ANOTHER SIGNIFICANT COLD SHOT LIKE THE ONE TUESDAY NIGHT...BUT
WHEN IS NOW A QUESTION MARK. THE 22.00Z GFS SHOWS THE SHOT COMING IN
ON THURSDAY...SIMILAR TO PAST ECMWF RUNS. HOWEVER...THE 22.00Z ECMWF
NOW SUGGESTS THAT COLD SHOT IS DELAYED UNTIL FRIDAY MORNING. THE BAD
PART ABOUT THE ECMWF IS THAT THE COLD SHOT IS EVEN COLDER TOWARDS
SATURDAY MORNING. FOR NOW STAYED WITH A CONSENSUS FORECAST ON
TEMPERATURES WEDNESDAY NIGHT THROUGH FRIDAY NIGHT. WHICHEVER
SOLUTION PANS OUT...MORE WIND CHILL ADVISORIES ARE LIKELY.
ON A CLIMATE NOTE...BASED ON CURRENT TEMPERATURE FORECASTS...
LA CROSSE WILL END UP 3RD OR 4TH COLDEST FOR THE MONTH OF FEBRUARY.
&&
.CLIMATE...COLD FEBRUARY AND WINTER SEASON
ISSUED AT 526 AM CST SAT FEB 22 2014
UPON A MORE DETAILED LOOK AT THE CURRENT TEMPERATURE FORECASTS THRU
THE END OF THE MONTH...LA CROSSE WOULD END WITH WITH A FEB AVERAGE
TEMPERATURE OF 9.4 DEGREES. THIS WOULD TIE WITH 1899 FOR THIRD
COLDEST FEB OF RECORD...BEHIND ONLY FEB OF 1873 AND 1936. THE WINTER
SEASON /DEC-FEB/ WOULD END UP WITH AN AVERAGE TEMPERATURE OF 11.5
DEGREES...FIFTH COLDEST WINTER OF RECORD.
FOR ROCHESTER...FEB WOULD END UP WITH AN AVERAGE TEMPERATURE OF 7.2
DEGREES...FOURTH COLDEST OF RECORD...BEHIND FEB OF 1917...1936 AND
1979. THE WINTER SEASON /DEC-FEB/ WOULD END UP WITH AN AVERAGE
TEMPERATURE OF 9.0 DEGREES...TIED FOR FIFTH COLDEST WINTER OF RECORD.
THIS WOULD BE THE COLDEST WINTER IN 35 YEARS. ONE WOULD HAVE TO GO
BACK TO THE WINTERS OF 1976-1977...1977-1978 AND 1978-1979 TO FIND A
COMPARABLY COLD WINTER AT BOTH ROCHESTER AND LA CROSSE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1100 AM CST SAT FEB 22 2014
HIGH PRESSURE EXTENDING INTO THE NORTHERN PLAINS WILL WORK TO KEEP
THE LOCAL AREA UNDER SCT/SKC SKIES AND VFR CONDITIONS TONIGHT
THROUGH SUNDAY. SFC GRADIENT DOESN/T SLACKEN TOO MUCH...SO EXPECT
WINDS TO HOLD MOSTLY IN THE 10-15 KT RANGE.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM....AJ
CLIMATE......RRS
AVIATION.....RIECK
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
526 AM CST SAT FEB 22 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 232 AM CST SAT FEB 22 2014
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED NORTHWEST FLOW FROM EASTERN ALASKA INTO THE CENTRAL PLAINS...
AND THURSDAYS WINTER STORM AS A LARGE UPPER LOW OVER FAR NORTHERN
ONTARIO. THE FORECAST AREA CONTINUES TO BE INFLUENCED BY THE
CIRCULATION AROUND THE LARGE UPPER LOW WITH A SERIES OF WEAK
SHORTWAVES ROTATING AROUND IT MOVING THROUGH THE FORECAST AREA.
PLENTY OF DRY AIR SEEN ON THE 00Z MPX SOUNDING HAS KEPT THESE
SHORTWAVES FROM PRODUCING ANYTHING. IN FACT...OUTSIDE OF SOME LOW
STRATUS NORTH OF HIGHWAY 10 IN WISCONSIN...SKIES ARE MOSTLY CLEAR.
LOW TO MID LEVEL NORTHWEST WINDS AROUND THE LOWS CIRCULATION
CONTINUE TO DRAW COLDER AIR SOUTH OUT OF CENTRAL CANADA INTO THE
FORECAST AREA. 850MB TEMPS AT MPX DROPPED FROM -4C AT 00Z FRIDAY
TO -13C AT 00Z SATURDAY. WELL OFF TO THE NORTHWEST...THERE ARE TWO
IMPORTANT SHORTWAVES OF NOTE WHICH INFLUENCE MONDAYS FORECAST...ONE
OVER NORTHERN ALBERTA AND A SECOND IN THE YUKON.
VERY LITTLE CHANGE IN THE UPPER LEVEL PATTERN IS PROGGED OVER THE
NEXT 24 HOURS. THIS MEANS THE FORECAST AREA WILL CONTINUE TO BE
INFLUENCED BY THE CIRCULATION AROUND THE UPPER AND SURFACE LOWS IN
FAR NORTHERN ONTARIO...ALLOWING A FEED OF DRY...COLD AIR ON
NORTHWEST WINDS TO CONTINUE. MAY HAVE TO KEEP A WATCH FOR SOME
FLURRIES THIS MORNING ACROSS NORTHEAST IOWA AND FAR SOUTHWEST
WI...ASSOCIATED WITH A SHORTWAVE TRACKING FROM SOUTH DAKOTA INTO
NORTHERN ILLINOIS. CURRENTLY THINK THE DRY AIR WILL WIN OUT AND ANY
MEANINGFUL SNOW/FLURRIES WILL STAY TO THE SOUTH.
925MB TEMP PROGS SUGGEST THAT THE HIGHER SUN ANGLE HERE IN LATE
FEBRUARY WILL HELP TO MODIFY SOME OF THE COLD AIR DURING THE DAYTIME
HOURS. STILL...READINGS AT 18Z OF -12 TO -14C AND FRESH SNOW ONLY
SUPPORT HIGHS IN THE MID TEENS TO MID 20S. 925MB WINDS STAYING UP
TONIGHT...ON THE ORDER OF 30 TO 35 KT...WILL HELP KEEP SURFACE WINDS
FROM DECOUPLING. HOWEVER...THESE WINDS DROP TEMPS TO -14 TO -18C BY
12Z SUNDAY. THIS COLDER AIR WILL EASILY ALLOW FOR LOWS IN THE SINGLE
DIGITS ABOVE ZERO...AND EVEN IN THE SINGLE DIGITS BELOW ZERO IN THE
TYPICAL COLD SPOTS. WIND CHILLS COULD GET CLOSE ENOUGH TO WARRANT A
WIND CHILL ADVISORY OVER TAYLOR/CLARK COUNTIES LATE TONIGHT INTO
SUNDAY MORNING. GIVEN WIND CHILLS CURRENTLY FORECAST IN THE 18 TO 23
BELOW ZERO RANGE FOR THAT AREA...WILL LET LATER SHIFTS TO DECIDE ON
THE ADVISORY.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 232 AM CST SAT FEB 22 2014
THE RETURN OF ARCTIC AIR REMAINS THE BIG IMPACT ITEM IN THE LONG
TERM...WITH A BRIEF BOUT OF SNOW POSSIBLE MONDAY INTO MONDAY NIGHT.
MODELS CONTINUE TO ADVERTISE THE CURRENT RIDGE OVER THE EASTERN
PACIFIC INTO ALASKA WILL DEVELOP INTO AN OMEGA BLOCK OVER THE NEXT
FEW DAYS...WITH ONLY A SLIGHT MOVEMENT EASTWARD. THIS OMEGA BLOCK
ALLOWS SHORTWAVES OVER THE ARCTIC TO DIVE SOUTH INTO THE NORTHERN
U.S....BRINGING THE ARCTIC AIR WITH THEM. ITS WORTH NOTING THAT
HIGHS OBSERVED ON FRIDAY ACROSS THE NORTHWEST TERRITORIES AND
NUNAVUT REGION WERE IN THE TEENS AND 20S BELOW ZERO. HEADING INTO
LATE NEXT WEEK AND NEXT WEEKEND...A CONSISTENT SIGNAL EXISTS THAT
THE SOUTHERN END OF THE OMEGA BLOCK WILL BREAK DOWN. FOR NOW IT
APPEARS WE WILL STAY INFLUENCED BY TROUGHING AND ARCTIC AIR ACROSS
SOUTHERN CANADA.
THE MAJORITY OF THE SHORTWAVES DROPPING OUT OF THE ARCTIC ARE
SUGGESTED TO HAVE LITTLE IF ANY MOISTURE WITH THEM. THUS...THERE IS
NOT A LOT OF PRECIPITATION FORECAST IN THE LONG TERM. THE LONE
EXCEPTION TO THIS IS ON MONDAY...WHEN THE SHORTWAVES OVER NORTHERN
ALBERTA AND THE YUKON ARE PROGGED TO COME ACROSS THE FORECAST AREA
AS A PHASED SHORTWAVE TROUGH. PRECIPITABLE WATER VALUES ACCORDING
TO THE 22.00Z GFS ARE SUGGESTED TO CLIMB TO 0.20 INCHES...WHICH
COMBINED WITH THE POTENT LOOK OF THE SHORTWAVES SHOULD SQUEEZE OUT
SOME SNOW. THE 22.00Z NAM WAS THE DRIEST OF GUIDANCE...BUT THE WORRY
POSED BY THE MODEL SUGGESTING A DRY SCENARIO KEPT CHANCES FROM GOING
MUCH ABOVE 50. IF IT COMES AROUND TOWARDS A WETTER SCENARIO...
CHANCES CAN BE RAISED. TIMING WISE...MODELS HAVE SLOWED THE
PROGRESSION OF THE SNOW. CONSENSUS SEEMS TO FAVOR SNOW MOVING INTO
LOCATIONS WEST OF THE MISSISSIPPI RIVER DURING THE AFTERNOON...THEN
MARCHING EAST ACROSS THE REST OF THE AREA DURING THE EVENING. AFTER
06Z TUESDAY...MUCH OF THE SNOW LOOKS TO BE OVERWITH. LACK OF
MOISTURE WILL KEEP SNOW AMOUNTS DOWN...BUT WITH SNOW TO WATER RATIOS
NEAR 20 TO 1 SHOULD HELP IN ACCUMULATING ANYWHERE FROM 0.5 TO 2
INCHES OF SNOWFALL.
NOW REGARDING THE COLD. SUNDAY AND MONDAY LOOK PRETTY SIMILAR TO
TODAY WITH REGARDS TO HIGHS...WITH JUST A SLIGHT COOLING EACH DAY AS
COLDER AIR FILTERS IN. A MORE SIGNIFICANT PUSH OF ARCTIC AIR COMES
INTO THE FORECAST AREA TUESDAY INTO TUESDAY NIGHT. IN FACT...925MB
TEMPS FALL FROM -14 TO -18C AT 12Z TUESDAY TO -22 TO -25C BY 12Z
WEDNESDAY. THESE REMAIN PRETTY CONSISTENT...AND IT COMES WITH A
20-40 KT 925MB WIND TOO...SUGGESTING A WIND CHILL ADVISORY IS HIGHLY
LIKELY. A PERIOD OF WARM ADVECTION REMAINS ON TAP TO COME IN ON
WEDNESDAY...THOUGH COUNTER-ACTED FROM A WIND CHILL PERSPECTIVE
BECAUSE OF A BRISK WEST WIND. BEYOND WEDNESDAY...THERE REMAINS SIGNS
OF ANOTHER SIGNIFICANT COLD SHOT LIKE THE ONE TUESDAY NIGHT...BUT
WHEN IS NOW A QUESTION MARK. THE 22.00Z GFS SHOWS THE SHOT COMING IN
ON THURSDAY...SIMILAR TO PAST ECMWF RUNS. HOWEVER...THE 22.00Z ECMWF
NOW SUGGESTS THAT COLD SHOT IS DELAYED UNTIL FRIDAY MORNING. THE BAD
PART ABOUT THE ECMWF IS THAT THE COLD SHOT IS EVEN COLDER TOWARDS
SATURDAY MORNING. FOR NOW STAYED WITH A CONSENSUS FORECAST ON
TEMPERATURES WEDNESDAY NIGHT THROUGH FRIDAY NIGHT. WHICHEVER
SOLUTION PANS OUT...MORE WIND CHILL ADVISORIES ARE LIKELY.
ON A CLIMATE NOTE...BASED ON CURRENT TEMPERATURE FORECASTS...
LA CROSSE WILL END UP 3RD OR 4TH COLDEST FOR THE MONTH OF FEBRUARY.
&&
.CLIMATE...COLD FEBRUARY AND WINTER SEASON
ISSUED AT 526 AM CST SAT FEB 22 2014
UPON A MORE DETAILED LOOK AT THE CURRENT TEMPERATURE FORECASTS THRU
THE END OF THE MONTH...LA CROSSE WOULD END WITH WITH A FEB AVERAGE
TEMPERATURE OF 9.4 DEGREES. THIS WOULD TIE WITH 1899 FOR THIRD
COLDEST FEB OF RECORD...BEHIND ONLY FEB OF 1873 AND 1936. THE WINTER
SEASON /DEC-FEB/ WOULD END UP WITH AN AVERAGE TEMPERATURE OF 11.5
DEGREES...FIFTH COLDEST WINTER OF RECORD.
FOR ROCHESTER...FEB WOULD END UP WITH AN AVERAGE TEMPERATURE OF 7.2
DEGREES...FOURTH COLDEST OF RECORD...BEHIND FEB OF 1917...1936 AND
1979. THE WINTER SEASON /DEC-FEB/ WOULD END UP WITH AN AVERAGE
TEMPERATURE OF 9.0 DEGREES...TIED FOR FIFTH COLDEST WINTER OF RECORD.
THIS WOULD BE THE COLDEST WINTER IN 35 YEARS. ONE WOULD HAVE TO GO
BACK TO THE WINTERS OF 1976-1977...1977-1978 AND 1978-1979 TO FIND A
COMPARABLY COLD WINTER AT BOTH ROCHESTER AND LA CROSSE.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 526 AM CST SAT FEB 22 2014
VERY LITTLE CHANGE IS EXPECTED AT THE TAF SITES THRU TODAY AND
TONIGHT...INTO SUN/SUN NIGHT. HIGH PRESSURE OVER SASKAT/ALB WITH
RIDGING INTO IA WILL MOVE LITTLE DURING THE NEXT COUPLE DAYS. THIS
WILL PROVIDE AN EXTENDED PERIOD OF GOOD VFR CONDITIONS. WITH LITTLE
CHANGE IN THE PRESSURE GRADIENT OVER THE REGION...WINDS WILL
CONTINUE TO BE WEST TO NORTHWEST AT SPEEDS OF 10 TO 15 KNOTS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM....AJ
CLIMATE......RRS
AVIATION.....RRS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
232 AM CST SAT FEB 22 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 232 AM CST SAT FEB 22 2014
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED NORTHWEST FLOW FROM EASTERN ALASKA INTO THE CENTRAL PLAINS...
AND THURSDAYS WINTER STORM AS A LARGE UPPER LOW OVER FAR NORTHERN
ONTARIO. THE FORECAST AREA CONTINUES TO BE INFLUENCED BY THE
CIRCULATION AROUND THE LARGE UPPER LOW WITH A SERIES OF WEAK
SHORTWAVES ROTATING AROUND IT MOVING THROUGH THE FORECAST AREA.
PLENTY OF DRY AIR SEEN ON THE 00Z MPX SOUNDING HAS KEPT THESE
SHORTWAVES FROM PRODUCING ANYTHING. IN FACT...OUTSIDE OF SOME LOW
STRATUS NORTH OF HIGHWAY 10 IN WISCONSIN...SKIES ARE MOSTLY CLEAR.
LOW TO MID LEVEL NORTHWEST WINDS AROUND THE LOWS CIRCULATION
CONTINUE TO DRAW COLDER AIR SOUTH OUT OF CENTRAL CANADA INTO THE
FORECAST AREA. 850MB TEMPS AT MPX DROPPED FROM -4C AT 00Z FRIDAY
TO -13C AT 00Z SATURDAY. WELL OFF TO THE NORTHWEST...THERE ARE TWO
IMPORTANT SHORTWAVES OF NOTE WHICH INFLUENCE MONDAYS FORECAST...ONE
OVER NORTHERN ALBERTA AND A SECOND IN THE YUKON.
VERY LITTLE CHANGE IN THE UPPER LEVEL PATTERN IS PROGGED OVER THE
NEXT 24 HOURS. THIS MEANS THE FORECAST AREA WILL CONTINUE TO BE
INFLUENCED BY THE CIRCULATION AROUND THE UPPER AND SURFACE LOWS IN
FAR NORTHERN ONTARIO...ALLOWING A FEED OF DRY...COLD AIR ON
NORTHWEST WINDS TO CONTINUE. MAY HAVE TO KEEP A WATCH FOR SOME
FLURRIES THIS MORNING ACROSS NORTHEAST IOWA AND FAR SOUTHWEST
WI...ASSOCIATED WITH A SHORTWAVE TRACKING FROM SOUTH DAKOTA INTO
NORTHERN ILLINOIS. CURRENTLY THINK THE DRY AIR WILL WIN OUT AND ANY
MEANINGFUL SNOW/FLURRIES WILL STAY TO THE SOUTH.
925MB TEMP PROGS SUGGEST THAT THE HIGHER SUN ANGLE HERE IN LATE
FEBRUARY WILL HELP TO MODIFY SOME OF THE COLD AIR DURING THE DAYTIME
HOURS. STILL...READINGS AT 18Z OF -12 TO -14C AND FRESH SNOW ONLY
SUPPORT HIGHS IN THE MID TEENS TO MID 20S. 925MB WINDS STAYING UP
TONIGHT...ON THE ORDER OF 30 TO 35 KT...WILL HELP KEEP SURFACE WINDS
FROM DECOUPLING. HOWEVER...THESE WINDS DROP TEMPS TO -14 TO -18C BY
12Z SUNDAY. THIS COLDER AIR WILL EASILY ALLOW FOR LOWS IN THE SINGLE
DIGITS ABOVE ZERO...AND EVEN IN THE SINGLE DIGITS BELOW ZERO IN THE
TYPICAL COLD SPOTS. WIND CHILLS COULD GET CLOSE ENOUGH TO WARRANT A
WIND CHILL ADVISORY OVER TAYLOR/CLARK COUNTIES LATE TONIGHT INTO
SUNDAY MORNING. GIVEN WIND CHILLS CURRENTLY FORECAST IN THE 18 TO 23
BELOW ZERO RANGE FOR THAT AREA...WILL LET LATER SHIFTS TO DECIDE ON
THE ADVISORY.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 232 AM CST SAT FEB 22 2014
THE RETURN OF ARCTIC AIR REMAINS THE BIG IMPACT ITEM IN THE LONG
TERM...WITH A BRIEF BOUT OF SNOW POSSIBLE MONDAY INTO MONDAY NIGHT.
MODELS CONTINUE TO ADVERTISE THE CURRENT RIDGE OVER THE EASTERN
PACIFIC INTO ALASKA WILL DEVELOP INTO AN OMEGA BLOCK OVER THE NEXT
FEW DAYS...WITH ONLY A SLIGHT MOVEMENT EASTWARD. THIS OMEGA BLOCK
ALLOWS SHORTWAVES OVER THE ARCTIC TO DIVE SOUTH INTO THE NORTHERN
U.S....BRINGING THE ARCTIC AIR WITH THEM. ITS WORTH NOTING THAT
HIGHS OBSERVED ON FRIDAY ACROSS THE NORTHWEST TERRITORIES AND
NUNAVUT REGION WERE IN THE TEENS AND 20S BELOW ZERO. HEADING INTO
LATE NEXT WEEK AND NEXT WEEKEND...A CONSISTENT SIGNAL EXISTS THAT
THE SOUTHERN END OF THE OMEGA BLOCK WILL BREAK DOWN. FOR NOW IT
APPEARS WE WILL STAY INFLUENCED BY TROUGHING AND ARCTIC AIR ACROSS
SOUTHERN CANADA.
THE MAJORITY OF THE SHORTWAVES DROPPING OUT OF THE ARCTIC ARE
SUGGESTED TO HAVE LITTLE IF ANY MOISTURE WITH THEM. THUS...THERE IS
NOT A LOT OF PRECIPITATION FORECAST IN THE LONG TERM. THE LONE
EXCEPTION TO THIS IS ON MONDAY...WHEN THE SHORTWAVES OVER NORTHERN
ALBERTA AND THE YUKON ARE PROGGED TO COME ACROSS THE FORECAST AREA
AS A PHASED SHORTWAVE TROUGH. PRECIPITABLE WATER VALUES ACCORDING
TO THE 22.00Z GFS ARE SUGGESTED TO CLIMB TO 0.20 INCHES...WHICH
COMBINED WITH THE POTENT LOOK OF THE SHORTWAVES SHOULD SQUEEZE OUT
SOME SNOW. THE 22.00Z NAM WAS THE DRIEST OF GUIDANCE...BUT THE WORRY
POSED BY THE MODEL SUGGESTING A DRY SCENARIO KEPT CHANCES FROM GOING
MUCH ABOVE 50. IF IT COMES AROUND TOWARDS A WETTER SCENARIO...
CHANCES CAN BE RAISED. TIMING WISE...MODELS HAVE SLOWED THE
PROGRESSION OF THE SNOW. CONSENSUS SEEMS TO FAVOR SNOW MOVING INTO
LOCATIONS WEST OF THE MISSISSIPPI RIVER DURING THE AFTERNOON...THEN
MARCHING EAST ACROSS THE REST OF THE AREA DURING THE EVENING. AFTER
06Z TUESDAY...MUCH OF THE SNOW LOOKS TO BE OVERWITH. LACK OF
MOISTURE WILL KEEP SNOW AMOUNTS DOWN...BUT WITH SNOW TO WATER RATIOS
NEAR 20 TO 1 SHOULD HELP IN ACCUMULATING ANYWHERE FROM 0.5 TO 2
INCHES OF SNOWFALL.
NOW REGARDING THE COLD. SUNDAY AND MONDAY LOOK PRETTY SIMILAR TO
TODAY WITH REGARDS TO HIGHS...WITH JUST A SLIGHT COOLING EACH DAY AS
COLDER AIR FILTERS IN. A MORE SIGNIFICANT PUSH OF ARCTIC AIR COMES
INTO THE FORECAST AREA TUESDAY INTO TUESDAY NIGHT. IN FACT...925MB
TEMPS FALL FROM -14 TO -18C AT 12Z TUESDAY TO -22 TO -25C BY 12Z
WEDNESDAY. THESE REMAIN PRETTY CONSISTENT...AND IT COMES WITH A
20-40 KT 925MB WIND TOO...SUGGESTING A WIND CHILL ADVISORY IS HIGHLY
LIKELY. A PERIOD OF WARM ADVECTION REMAINS ON TAP TO COME IN ON
WEDNESDAY...THOUGH COUNTER-ACTED FROM A WIND CHILL PERSPECTIVE
BECAUSE OF A BRISK WEST WIND. BEYOND WEDNESDAY...THERE REMAINS SIGNS
OF ANOTHER SIGNIFICANT COLD SHOT LIKE THE ONE TUESDAY NIGHT...BUT
WHEN IS NOW A QUESTION MARK. THE 22.00Z GFS SHOWS THE SHOT COMING IN
ON THURSDAY...SIMILAR TO PAST ECMWF RUNS. HOWEVER...THE 22.00Z ECMWF
NOW SUGGESTS THAT COLD SHOT IS DELAYED UNTIL FRIDAY MORNING. THE BAD
PART ABOUT THE ECMWF IS THAT THE COLD SHOT IS EVEN COLDER TOWARDS
SATURDAY MORNING. FOR NOW STAYED WITH A CONSENSUS FORECAST ON
TEMPERATURES WEDNESDAY NIGHT THROUGH FRIDAY NIGHT. WHICHEVER
SOLUTION PANS OUT...MORE WIND CHILL ADVISORIES ARE LIKELY.
ON A CLIMATE NOTE...BASED ON CURRENT TEMPERATURE FORECASTS...
LA CROSSE WILL END UP 3RD OR 4TH COLDEST FOR THE MONTH OF FEBRUARY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1109 PM CST FRI FEB 21 2014
VERY LITTLE CHANGE IS EXPECTED TO OCCUR OVER THE NEXT 24 HOURS.
HIGH PRESSURE WILL REMAINED CENTERED OVER SOUTHERN SASKATCHEWAN
WITH THE RIDGE AXIS EXTENDING SOUTHEAST INTO IOWA WHILE LOW
PRESSURE REMAINS NEAR HUDSONS BAY. THIS WILL PROVIDE AN EXTENDED
PERIOD OF VFR CONDITIONS AND WITH LITTLE CHANGE IN THE
GRADIENT...THE WINDS WILL CONTINUE TO BE WEST TO NORTHWEST AT
SPEEDS BETWEEN 10 AND 15 KNOTS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...04
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
1040 PM CST FRI FEB 21 2014
.UPDATE...A WEAK SHORTWAVE TROUGH OVER SD WILL TRACK ACROSS NRN IL
ON SAT AND HELP INITIATE MID LEVEL FRONTOGENESIS. ALL MODELS WITH
THE EXCEPTION OF THE HRRR DEVELOP A NARROW BAND OF LGT SNOW OVER
NRN IL...WHILE THE HRRR DEVELOPS IT OVER SRN WI. FAIRLY CONFIDENT
THE SNOW WILL REMAIN SOUTH WITH PARTLY CLOUDY TO MO SUNNY SKIES
OVER THE FORECAST AREA.
&&
.AVIATION/06Z TAFS/...LOW LEVEL WIND SHEAR WILL REMAIN POSSIBLE
THROUGH 15Z SAT DUE TO A WLY 40-45 KT LLJ. OTHERWISE VFR
CONDITIONS WILL PREVAIL SAT AND SAT NT.
&&
.PREV DISCUSSION... /ISSUED 248 PM CST FRI FEB 21 2014/
SHORT TERM...
TONIGHT AND SATURDAY...FORECAST CONFIDENCE IS HIGH.
STRONG LOW PRESSURE CONTINUES TO GRADUALLY PULL AWAY FROM THE REGION
THIS AFTERNOON. THE STRONG PRESSURE GRADIENT WILL CONTINUE TO
GRADUALLY WEAKEN INTO TONIGHT...ALLOWING FOR GUSTS TO WEAKEN AROUND
OR BELOW 39 KNOTS AT 21Z...AND TO AROUND 30 KNOTS BY 00Z SATURDAY.
THUS...WILL ALLOW THE WIND ADVISORY TO EXPIRE.
WINDS WILL REMAIN WESTERLY TONIGHT INTO SATURDAY...AS PRESSURE
GRADIENT REMAINS SOMEWHAT TIGHT WITH INFLUENCE OF CANADIAN HIGH
PRESSURE WELL TO THE NORTHWEST. CLOUDS WILL SHIFT NORTHEAST OUT OF
THE AREA BY SUNSET. AREAS OF LOW TO MID LEVEL CLOUDS WILL PASS BY
THE AREA JUST TO THE SOUTH AND SOUTHWEST OF THE AREA TONIGHT INTO
SATURDAY. THIS PERIOD SHOULD BE MOSTLY CLEAR.
COLDER AIR WILL CONTINUE TO POUR INTO THE AREA DURING THIS TIME.
LOWS TONIGHT SHOULD DROP INTO THE SINGLE DIGITS NORTHWEST TO TEENS
SOUTHEAST. HIGHS SATURDAY WILL BE IN THE 20S...HIGHER IN THE
SOUTHEAST.
SATURDAY NIGHT AND SUNDAY...FORECAST CONFIDENCE...HIGH
THE MAIN POLAR JET EXTENDS ACROSS THE MID MISSISSIPPI AND OHIO
VALLEY AREA AT THE BASE OF THE BROAD UPPER CANADIAN TROUGH. 700 MB
DOWNWARD MOTION SATURDAY NIGHT BECOMES WEAK UPWARD DURING THE DAY
SUNDAY. 850/700 MB RELATIVE HUMIDITY IS LOW...ALTHOUGH SOME HIGHER
RH ACROSS THE UPPER GREAT LAKES GETS CLOSE TO THE FOND DU LAC AND
SHEBOYGAN AREA ON SUNDAY.
NOT MUCH CHANGE WITH THE SURFACE HIGH STILL RIDGING THROUGH THE
PLAINS TOWARDS THE MISSISSIPPI RIVER. SURFACE GRADIENT STILL WILL
SUPPORT ENOUGH WIND TO REDUCE WIND CHILLS TO NEAR 5 BELOW TO
10 BELOW SATURDAY NIGHT AND AROUND 5 ABOVE DURING THE DAY.
SUNDAY NIGHT AND MONDAY...FORECAST CONFIDENCE...HIGH
ONE SHORTWAVE MOVES INTO SOUTHEAST CANADA WHILE A SECOND
EXITS THE NORTHERN ROCKIES. 700 MB DOWNWARD MOTION BECOME WEAKLY
UPWARD OVER THE WEST MONDAY AFTERNOON. 700 MB RH INCREASES IN
AREAS WEST OF MADISON BY EVENING...BUT SATURATION IS STILL ALONG
AND WEST OF THE MISSISSIPPI RIVER ON THE NAM. THE GFS AND ECMWF
ARE FASTER AND BRINGS IN LIGHT SNOW TO MUCH OF SOUTHERN WISCONSIN
MONDAY AFTERNOON.
THE SURFACE WINDS FINALLY BECOME LIGHT AS THE SURFACE RIDGE BUILDS
INTO SOUTHERN WISCONSIN MONDAY AFTERNOON.
LONG TERM...
MONDAY NIGHT AND TUESDAY...FORECAST CONFIDENCE HIGH
A MID/UPPER SHORTWAVE MOVES ACROSS WISCONSIN MONDAY NIGHT. THE 00Z
ECMWF IS A LITTLE SLOWER AND FARTHER NORTH. THEN A SECOND
SHORTWAVE MOVES ACROSS THE NORTHERN PLAINS AND APPROACHES THE
UPPER MISSISSIPPI VALLEY TUESDAY.
ANY LIGHT SNOW SHOULD END BY SUNRISE TUESDAY AS HIGH PRESSURE
BUILDS ACROSS THE EASTERN PLAINS TOWARDS THE UPPER MISSISSIPPI
VALLEY.
WEDNESDAY...FORECAST CONFIDENCE...HIGH
THE LARGE MID/UPPER TROUGH CUTS OFF AND DROPS TO JUST NORTH OF
LAKE SUPERIOR.
THE LARGE RIDGE OF HIGH PRESSURE DROPS SOUTH ACROSS THE MIDDLE OF
THE U.S. THICKNESS VALUES DROP TO AROUND 490 TO 510 DECAMETERS
WEDNESDAY NIGHT THROUGH FRIDAY...FORECAST CONFIDENCE...HIGH
BOTH THE 12Z GFS AND 00Z ECMWF BRING A SURFACE TROUGH ACROSS
SOUTHERN WISCONSIN WEDNESDAY NIGHT. MOISTURE IS LIMITED WITH ONLY
A FEW HUNDREDTHS MAINLY ON THE GFS.
THEN THE COLD AIR GETS REINFORCED WITH RATHER BRISK NORTHWEST
WINDS THURSDAY. HIGH PRESSURE MOVES ACROSS WISCONSIN THURSDAY
NIGHT AND FRIDAY WITH VERY COLD TEMPERATURES THURSDAY NIGHT.
AVIATION/00Z TAFS/...
SOUTHWEST TO WEST WINDS OF 22 TO 25 KNOTS...GUSTING TO 33 TO 38
KNOTS...WILL GRADUALLY SUBSIDE INTO EARLY TONIGHT ACROSS TAF SITES.
THIS IS IN RESPONSE TO STRONG LOW PRESSURE MOVING FURTHER AWAY FROM
THE REGION. STILL MAY SEE WESTERLY GUSTS TO AROUND 20 KNOTS AT TIMES
ON SATURDAY. MOSTLY CLEAR SKIES ARE EXPECTED TONIGHT AND SATURDAY.
MARINE...
THE GALE WARNING HAS BEEN EXTENDED UNTIL 03Z SATURDAY ACROSS THE
NEARSHORE WATERS OF LAKE MICHIGAN. STRONG PRESSURE GRADIENT WILL
SLOWLY WEAKEN TONIGHT. THIS WILL ALLOW FOR SOUTHWEST TO WEST GUSTS
OF 35 TO 40 KNOTS EARLY THIS EVENING TO WEAKEN TO AROUND 30 KNOTS BY
LATER THIS EVENING. HIGH WAVES OF 3 TO 5 FEET ARE EXPECTED IN ICE
FREE AREAS INTO THIS EVENING...BEFORE DIMINISHING LATER TONIGHT.
A SMALL CRAFT ADVISORY WILL BE NEEDED FOR AT TIME LATER TONIGHT FOR
GUSTY WEST WINDS TO 30 KNOTS. THE PRESSURE GRADIENT WILL REMAIN
FAIRLY TIGHT THROUGH THE WEEKEND...POSSIBLY ALLOWING FOR 25 KNOT
GUSTS TO OCCUR. A SMALL CRAFT ADVISORY MAY BE NEEDED AT TIMES OVER
THE WEEKEND.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 6 AM CST SUNDAY FOR LMZ643>646.
&&
$$
UPDATE...GEHRING
TONIGHT/SATURDAY AND AVIATION/MARINE...WOOD
SATURDAY NIGHT THROUGH FRIDAY...HENTZ
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1026 PM MST SUN FEB 23 2014
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 300 PM MST SUN FEB 23 2014
CURRENTLY...LOW STRATUS HAS SLOWLY ERODED TO LEAVE SUNNY SKIES
ACROSS SOUTHERN COLORADO THIS AFTERNOON. TEMPERATURES HAVE BEEN
HIGHLY DEPENDENT ON WIND...WHERE ITS WESTERLY...TEMPERATURES HAVE
WARMED INTO THE 40S TO LOW 50S...WHERE ITS EASTERLY THEY HAVE
REMAINED IN THE 30S. EXPECT A COUPLE OF MORE DEGREES OF WARMING FOR
MOST AREAS...WITH THE EXCEPTION OF THE I-25 CORRIDOR...WHERE RAPID
WARM UPS ARE POSSIBLE AS WESTERLIES TRY AND MAKE IT EAST.
TONIGHT...BROAD NORTHWEST FLOW WILL ENCOMPASS THE REGION THROUGH THE
SHORT TERM. THE MAIN QUESTION WILL BE THE DEGREE OF LOW STRATUS
SLOSHING BACK WEST ACROSS THE PLAINS TONIGHT. FOLLOWED THE HRRR AND
LOCAL WRF...WHICH KEEPS STRATUS OUT ALONG THE KANSAS BORDER WITH
LITTLE PROGRESSION WEST. THE CAVEAT WILL BE HOW QUICKLY LEE TROUGH
DEVELOPS AND LOW LEVEL WESTERLY FLOW. BOTH THE HRRR AND WRF HAVE
WESTERLIES PICKING UP BY MIDNIGHT AND SHIFTING CLEAR OUT TO THE
KANSAS BORDER BY 10-11Z. THIS SHOULD ALLOW FOR RAPID CLEARING OF
ANY STRATUS OUT EAST BY DAYBREAK. IF THE LEE TROUGHING IS SLOWER TO
DEVELOP THAN MODELS PROJECT...STRATUS COULD MAKE IT MUCH FURTHER
WEST AND IMPACT THE WARMING EXPECTED BY SUNRISE. OVERNIGHT LOWS
WILL GENERALLY BE IN THE 20S ACROSS THE REGION...WITH SOME LOWER 30S
FOR THE BANANA BELT.
MONDAY...BROAD NORTHWEST FLOW ALOFT CONTINUES WITH DRY CONDITIONS
FOR SOUTHERN COLORADO. THE MAIN CONCERNS WILL BE BREEZY AFTERNOON
WINDS LEADING TO AREAS OF BLOWING DUST AND ELEVATED FIRE WEATHER
CONCERNS. STRONG MIXING BY THE AFTERNOON WILL BRING WIDESPREAD WIND
GUSTS TO NEAR 30 MPH ALONG THE LEE SLOPES...EAST INTO THE I-25
CORRIDOR. THESE GUSTY WINDS WILL LIKELY PRODUCE AREAS OF BLOWING
DUST...ESPECIALLY IN DUST PRONE AREAS SOUTH AND NORTH OF
PUEBLO...CREATING HAZARDOUS DRIVING CONDITIONS. IN
ADDITION...HUMIDITY VALUES ARE EXPECTED TO FALL INTO THE 10-15
PERCENT RANGE...AND WHEN COMBINED WITH THE GUSTY WINDS...WILL
PRODUCE DANGEROUS FIRE WEATHER CONDITIONS...PARTICULARLY ALONG THE
SOUTHERN I-25 CORRIDOR. EXPECT THE MIXING TO HELP BOOST
TEMPERATURES FOR TOMORROW WITH HIGHS TOPPING OUT IN THE LOWER TO MID
60S FOR THE LOWER ELEVATIONS. MOZLEY
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 300 PM MST SUN FEB 23 2014
...ACTIVE WX PATTERN AS PACIFIC STORMS BEGIN TO AFFECT THE REGION...
MON NITE-INTO WED...
CANADIAN HIGH PRESSURE WILL AFFECT THE HI PLAINS DURING THIS TIME
PERIOD WITH PERSISTENT UPSLOPE FLOW OVER THE PLAINS. A SHORTWAVE
ALOFT IN THE NW FLOW WILL MOVE ACROSS TUE
AFTERNOON/EVENING...AND THIS DISTURBANCE WILL BRING A CHANCE OF
RAIN AND SNOW TO THE PLAINS. FOR NOW PAINTED POPS IN THE HIGH
ISOLATED/LOW END SCATTERED CATEGORY. WITH THE MOIST UPSLOPE FLOW
EXPECT AN EXTENDED PERIOD OF CLOUDINESS TO AFFECT THE PLAINS. BY
LATER WED...SFC FLOW WILL TRANSITION TO SOUTHERLY AND THIS
SHOULD DECREASE THE CLOUDINESS. THE ONLY POSSIBLE EXCEPTION WILL
BE THE COS AREA WHERE THE SOUTHERLY FLOW MAY KEEP THE CLOUDS IN
PLACE UNTIL LATE MORNING. PERSISTENT SNOW SHOWERS WILL BE POSSIBLE
ACROSS THE C MTNS FROM MON NITE-EARLY WED
THURSDAY...
THE FIRST IN A SERIES OF PACIFIC WEATHER SYSTEMS WILL BEGIN TO
AFFECT THE REGION. VALLEY RAIN SHOWERS AND SNOW IN THE MTNS WILL
AFFECT THE CONTDVD BY THU LATE MORNING OR EARLY AFTERNOON AND
INCREASE THU AFTERNOON AND NITE. GIVEN THE QUALITY
MOISTURE...INSTABILITY...UPSLOPE FLOW AND FORCING...WE WILL LIKELY
SEE SNOWFALL AMOUNTS REQUIRING HILITES (WINTER STORM WARNING?) FOR
THE CONTDVD.
LATE THU NITE INTO FRIDAY...
UPSLOPE FLOW DEVELOPS ON THE PLAINS AND WE WILL SEE COOLER
WX...CLOUDINESS AND A CHANCE OF SOME PRECIP RETURNING TO THE LOWER
ELEVATIONS.
WEEKEND...
FRI NITE INTO EARLY SATURDAY A BRIEF RIDGE WILL BUILD ALOFT
DECREASING THE CLOUDS AND ENDING THE PRECIP...BUT ANOTHER STRONGER
PACIFIC STORM WILL BE QUICKLY MOVING IN. AS THIS PACIFIC STORM MOVES
TOWARDS THE CONTDVD...ANOTHER REINFORCING CANADIAN HIGH PRESSURE
SYSTEM WILL BE MOVING DOWN THE PLAINS...AND WILL BE AFFECTING THE
LOWER ELEVATIONS BY LATER SATURDAY MORNING. SNOW WILL DEVELOP ONCE
AGAIN OVER THE MTNS DURING THE DAY SATURDAY WITH PRECIP DEVELOPING
ON THE PLAINS LATE SAT AFTERNOON/EVENING. GUIDANCE AT THIS TIME IS
FAVORING THE PALMER DVD BUT I WOULD NOT BE TOO SURPRISED IF ALL OF
THE PLAINS RECEIVE SOME PRECIP SAT NITE INTO SUNDAY AS THE MIDLVL
TROUGH MOVES OVER THE REGION. OVERALL METEOROLOGICAL CONDITIONS
FOR THIS WEEKENDS STORM LOOK PRETTY GOOD GIVEN THAT THE COLD AIR
WILL ALREADY BE IN PLACE AS THE DYNAMICS MOVE OVER THE REGION. FOR
NOW I GOT TEMPS IN THE 30S AND 40S FOR THE WEEKEND WITH SLIGHT/LOW
END SCT POPS FOR THE AREA. I WOULD NOT BE TOO SURPRISED IF THE
TEMPS ARE LOWERED AND THE POPS ARE INCREASED AS WE GET CLOSER TO
THIS EVENT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1019 PM MST SUN FEB 23 2014
MVFR TO IFR STRATUS IS WORKING ITS WAY WESTWARD ACROSS SOUTHEAST
CO TONIGHT. FORECAST MODELS TYPICALLY HAVE A TOUGH TIME
FORECASTING WESTWARD EXTENT AND BASED ON TRENDS IN LATEST SATELLITE FOG
PRODUCT AND IN RAP13...HAVE PUT A TEMPO GROUP FOR BKN010 AT
KCOS...AND A PREVAILING MVFR CIG (BKN015) AT KPUB. ITS POSSIBLE
STRATUS DECK COULD STALL OUT TO THE EAST OF THE KCOS
TERMINAL...AND GIVEN THE UNCERTAINTY DECIDED TO KEEP IT IN A TEMPO
GROUP FOR NOW. ONCE WINDS SHIFT OUT OF THE NORTH...THAT SHOULD
ERODE IT AWAY FROM KCOS FAIRLY EARLY MONDAY MORNING (10Z)...AND
AN HOUR OR SO LATER (11Z) AT KPUB. GUSTY WEST TO NORTHWEST WINDS
WILL KICK IN AT KPUB AROUND 18Z ON MONDAY WITH WINDS REMAINING A
LITTLE LIGHTER FOR KCOS. A COLD FRONT WILL MOVE THROUGH SE CO
MONDAY EVENING AND HAVE IT TIMED TO PASS THROUGH KCOS AROUND 04Z
AND KPUB AROUND 05Z BRINGING A PERIOD OF GUSTY NORTHEAST WINDS.
KALS WILL REMAIN VFR WITH WIND SPEEDS 10 KTS OR LESS THROUGH THE
NEXT 24 HOURS. -KT
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
FIRE WEATHER WATCH FROM 10 AM MST MONDAY THROUGH MONDAY
AFTERNOON FOR COZ228>230.
&&
$$
SHORT TERM...MOZLEY
LONG TERM...HODANISH
AVIATION...KT
AREA FORECAST DISCUSSION
NWS TAUNTON MA
357 AM EST MON FEB 24 2014
.SYNOPSIS...
A STRONG COLD FRONT CROSSES THE REGION TONIGHT...BRINGING
PROGRESSIVELY COLDER CONDITIONS THROUGH NEXT WEEKEND. MAINLY DRY
CONDITIONS WILL BE IN PLACE AS LARGE HIGH PRESSURE MOVES ACROSS.
ONE EXCEPTION WILL BE FOR THE RISK OF ACCUMULATING SNOWFALL FOR
WEDNESDAY AS LOW PRESSURE DEVELOPS WELL SOUTH OF NEW ENGLAND.
ANOTHER LOW MAY BRING SOME SNOWFALL NEXT WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
A COMBINATION OF BOTH OBS AND MSAS SUGGEST SFC COLD FRONT HAS
MOVED OFFSHORE OF ALL SRN NEW ENGLAND COASTLINES SAVE FOR THE
CAPE/ISLANDS AS OF 0830Z. NOW IN CLOSE ASSOCIATION WITH THIS FRONT
IS A BAND OF WSR-88D ECHOS OF 25-30 DBZ WHICH ALSO CONTINUE TO
GRADUALLY SLIDE OFF THE S COAST AND SHOULD BE OFFSHORE OF
EVERYWHERE BY 10-12Z BASED ON CURRENT SPEED AND TIMING. DESPITE
THE ECHOS...PRECIP HAS REALLY STRUGGLED TO REACH THE SFC THANKS TO
10-15F DWPT DEPRESSIONS ACROSS THE REGION. EVEN THEN...WITH SFC
TEMPS ABOVE FREEZING AND A LACK OF HEAVY PRECIP TO FORCE THE NEAR
SFC LAYER TO WET-BULB...ANY PRECIP THAT HAS REACHED THE SFC HAS
BEEN IN THE FORM OF LIGHT RAIN. BASED EARLY MORNING POPS ON THE
LATEST RAP WHICH CONTINUES TO FOLLOW THIS BAND WELL BUT CAPPED ANY
POPS AT CHANCE.
OTHERWISE TODAY...AFTER THE FRONT/PRECIP BAND SHIFTS
OFFSHORE...STRONG COLD ADVECTION WILL DEFINE THE WX. H85
TEMPERATURES WILL BE DECLINING FROM AN AVERAGE OF ABOUT -5C TO
ABOUT -16C BY THE OVERNIGHT HOURS TONIGHT. DRY AIR WILL ALSO BE
RAPIDLY MOVING IN WITH TIME AS WELL. THEREFORE...EXPECT HIGH TEMPS
TO OCCUR BY LATE THIS MORNING WITH COOLING EXPECTED THROUGH THE
AFTERNOON HOURS...WITH RANGES FROM THE LOW TO UPPER 30S. THE
COMBINATION OF STRONG CYCLONIC CURVATURE ALOFT WITH A SHORTWAVE
MOVING ACROSS THE AREA...STEEP SFC-H9 LAPSE RATES ON THE ORDER OF
8C/KM AND A BIT OF TRAPPED MID LVL MOISTURE BENEATH A BUILDING
SUBSIDENCE INVERSION WILL LIKELY YIELD WIDESPREAD CU-STRATOCU
ACROSS THE AREA DURING PEAK HEATING. THE DEEP NEAR SFC UNSTABLE
LAYER MAY ALSO BE ENOUGH TO INDUCE SOME LOCALIZED FLURRY ACTIVITY
ESPECIALLY IN THE W WHERE CAA WILL BE MAXIMIZED. HAVE ADDED SOME
SLIGHT CHANCE POPS TO THE FORECAST ALONG WITH THE INCREASING
CLOUDS. OCEAN EFFECT CLOUDS ARE ALSO POSSIBLE ACROSS PORTIONS OF
CAPE COD GIVEN THE WIND TRAJECTORY AND OCEAN BL INSTABILITY.
ALSO...WITH THIS DEEP LAYER MIXING...MUCH OF THE MOMENTUM IN A
NEARLY 40 KT LLJ SHOULD BE TAPPED. THEREFORE...EXPECT BRISK NW
WINDS GUSTING 30-35 MPH AT TIMES THROUGH THE DAY. THIS WILL MAKE
FOR WIND CHILL VALUES IN THE 20S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
TONIGHT...
NOT TOO MUCH CHANGE FROM THE DAY AS CYCLONIC CURVATURE...DECENT
SFC PRES GRADIENT AND TRAPPED MID LVL MOISTURE REMAIN IN PLAY
ACROSS THE AREA. THEREFORE..EXPECT AT LEAST SOME CLOUDS AND WINDS
TO REMAIN THROUGH THE OVERNIGHT HOURS. WHILE THIS WILL LIMIT THE
ABILITY TO RADIATE...NORMAL DIURNAL TRENDS SHOULD STILL ALLOW MINS
INTO THE LOW TEENS AND 20S. WITH WINDS OF AROUND 10 MPH STILL
POSSIBLE...THIS WOULD YIELD SOME WIND CHILLS BELOW ZERO FOR
PORTIONS OF THE INTERIOR AND IN THE SINGLE DIGITS CLOSER TO THE
SHORELINES.
TUESDAY...
A COLD AND BRISK START IS EXPECTED AS WINDS CONTINUE TO GUST UP TO
ABOUT 20 MPH AFTER SUNRISE AND MIXING SETS UP. ANOTHER ROUND OF
PARTLY CLOUDY CONDITIONS AND HIGHER SUN ANGLES SHOULD ALLOW HIGHS
TO INCREASE INTO THE MID 20S TO LOW 30S DESPITE THIS COOLER START
BUT WITH WIND CHILL VALUES IN THE TEENS TO LOW 20S. MAINLY DRIER
WX AS NOSE OF HIGH PRES BEGINS TO BUILD OVER FROM THE
SW...LIMITING THE POTENTIAL FOR MORE FLURRY ACTIVITY IN COMPARISON
TO MON.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
HIGHLIGHTS...
* JANUARY-LIKE TEMPERATURES THIS WEEK AND AS WE ENTER MARCH NEXT
WEEKEND
* RISK FOR ACCUMULATING SNOW WED AND AGAIN NEXT WEEKEND
* OTHERWISE MAINLY DRY CONDITIONS PREVAIL
SYNOPTIC OVERVIEW...
NOT MUCH CHANGE IN THE FORECAST FROM PREVIOUS DAYS. HIGH AMPLITUDE
NORTHERN STREAM PATTERN DEVELOPS WITH POLAR VORTEX BEING DISPLACED
SOUTHWARD INTO ONTARIO BY THU. THIS RESULTS IN A STEADY STREAM OF
ARCTIC AIR INTO SOUTHERN NEW ENGLAND THIS WEEK AND INTO NEXT
WEEKEND. THAT/S THE EASY PART OF THE FORECAST. WHAT BECOMES
DIFFICULT TO NAIL DOWN AT THIS TIME RANGE IS THE INTENSITY AND TRACK
OF ANY EAST CYCLOGENESIS...AS ARCTIC SHORT WAVES PIVOT AROUND THE
SOUTHERN BASE OF THE POLAR VORTEX. FURTHER COMPLICATING THE FORECAST
IS IF PACIFIC ENERGY UNDERCUTTING THE WESTERN RIDGE INTERACTS
/PHASING VS UNPHASED/ WITH ARCTIC SHORT WAVE TROUGHS ALONG THE EAST
COAST.
MODEL PREFERENCES AND SENSIBLE WEATHER...
WEDNESDAY...00Z DETERMINISTIC GFS AND ECMWF IN AGREEMENT ON AN
UNPHASED SOLUTION WITH NORTHERN STREAM LOW MOVING ACROSS SOUTHEAST
CANADA AND EAST COAST CYCLOGENESIS TRACKING WELL SOUTHEAST OF
40N/70W BENCHMARK. HOWEVER APPEARS THERE WILL BE ENOUGH MID LEVEL
LIFT TO INDUCE AN INVERTED SURFACE TROUGH BETWEEN THESE TWO LOWS TO
GENERATE A FEW TENTHS OF QPF OVER SOUTHERN NEW ENGLAND. THUS A LOW
TO MODERATE RISK OF A FEW FLUFFY INCHES OF SNOW...WITH HIGHEST RISK
OVER SOUTHEAST MA.
HOWEVER CAN/T COMPLETELY RULE OUT A STRONGER/PHASED SOLUTION AS
ARCTIC SHORT WAVE/PV ANOMALY THAT INDUCES EAST COAST CYCLOGENESIS
IS CURRENTLY MOVING ACROSS NORTHWEST CANADA EARLY THIS MORNING.
MODELS LIKELY NOT SAMPLING THIS PACKET OF JET ENERGY VERY WELL
GIVEN THIS IS A DATA SPARSE AREA. THUS WILL HAVE TO WAIT UNTIL
THIS FEATURE ENTERS SOUTHERN CANADA BEFORE MODELS BEGIN BETTER
SAMPLING OF THIS JET ENERGY. IF THIS SHORT WAVE TROUGH IS MORE
AMPLIFIED THAN MODELS CURRENTLY SIMULATE...A TRACK CLOSER TO THE
COAST IS PLAUSIBLE. THEREFORE ITS STILL TOO EARLY TO LOCK INTO A
SINGLE SCENARIO. HOWEVER FOR THE MOMENT WILL PLAY THE MOST LIKELY
SCENARIO...A LOW TO MODERATE RISK OF A FEW INCHES OF FLUFFY SNOW.
THURSDAY THRU SUNDAY...ANOTHER ARCTIC FRONT MOVES ACROSS THE AREA
THU OR FRI WITH GEFS AND ECENS ENSEMBLE POST FRONTAL 850 MEAN TEMPS
VARYING FROM -15C TO -20C ACROSS SOUTHERN NEW ENGLAND. THUS COLDER
THAN NORMAL TEMPS HOWEVER ANY RECORD BREAKING COLD SHOULD REMAIN
WEST OF NEW ENGLAND ACROSS THE GREAT LAKES GIVEN PROXIMITY OF COLD
AIR CORE. WILL ALSO HAVE TO WATCH FOR POTENTIAL SNOW SQUALLS ALONG
AND AHEAD OF FRONTAL BOUNDARY...AS INCREASING SUN ANGLE /SAT MAR
1ST/ AND COLD AIR ALOFT WILL YIELD STEEP LOW LEVEL LAPSE RATES.
THEN NEXT WEEKEND THE FOCUS WILL BE ON PACIFIC ENERGY MARCHING
ACROSS THE SOUTHERN STATES AND ITS POSSIBLE INTERACTION/PHASING WITH
THE NORTHERN STREAM OVER THE NORTHEAST. THE 00Z GEFS AND ECENS
ENSEMBLE MEAN ARE WELL OFFSHORE WITH ANY CYCLOGENESIS...AS WELL AS
THE 00Z GFS. THE 00Z ECMWF IS MUCH CLOSER TO THE COAST BUT ALSO
WEAKER. GIVEN THE UNCERTAINTY WILL CONTINUE WITH CHANCE POPS FOR
NEXT WEEKEND.
&&
.AVIATION /08Z MONDAY THROUGH FRIDAY/...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH TUESDAY/...
THROUGH 12Z...MODERATE CONFIDENCE.
A FEW LIGHT SNOW/RAIN SHOWERS WILL SKIRT CT/RI/SE MA TERMINALS.
LITTLE IF ANY ACCUMULATION IS EXPECTED...BUT THE BEST CHANCE WILL
BE ACROSS SE MA. MAINLY VFR...BUT A SHORT PERIOD OF MVFR
CONDITIONS ARE POSSIBLE IN ANY SHOWERS.
TODAY AND TUESDAY...HIGH CONFIDENCE.
MAINLY VFR THROUGH THE PERIOD...BUT SOME LOW CU BETWEEN 030-060
POSSIBLE THROUGH DAYLIGHT HOURS ALONG WITH SOME LIGHT SNOW
SHOWERS POSSIBLE MAINLY W OF A IJD-ORH-EEN LINE TODAY. NW WINDS
GUSTING 25-30 KT AT TIMES TODAY...W WINDS GUST 20-25 KT ON TUE.
KBOS TERMINAL...HIGH CONFIDENCE IN TAF.
KBDL TERMINAL...HIGH CONFIDENCE IN TAF.
OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...
VFR ALONG WITH GUSTY WNW WINDS. THE EXCEPTION WILL BE WED WHEN WINDS
WILL BRIEFLY RELAX. HOWEVER A PERIOD OF SNOW IS POSSIBLE WED WITH
MVFR CONDITIONS. HIGHEST PROBABILITY OF SNOW AND MVFR CONDITIONS IS
ACROSS SOUTHEAST MA WED.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
THROUGH TUESDAY...HIGH CONFIDENCE.
W-NW WINDS WILL BE INCREASING THROUGH THE DAY TODAY WITH GUSTS
WIDESPREAD 25-30 KT EXPECTED. A FEW GUSTS MAY APPROACH GALE
FORCE...BUT THE MAJORITY SHOULD REMAIN BELOW. THESE WINDS WILL
MAINTAIN THROUGH THE OVERNIGHT HOURS TONIGHT...ONLY DIMINISHING
INTO THE MORNING HOURS FOR TUE THEN DROPPING BELOW SMALL CRAFT
THRESHOLDS BY THE LATE DAY TUE.
WITH INCREASING WINDS EXPECT SEAS TO BUILD AS WELL...REACHING
5-7FT AT TIMES MAINLY ON THE OCEAN WATERS.
OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...
GUSTY WNW WINDS AND PERIODS OF FREEZING SPRAY ARE EXPECTED AS ARCTIC
AIR OVERSPREADS THE REGION. WINDS BRIEFLY RELAX WED AS ONE AREA OF
LOW PRES TRACKS ACROSS SOUTHEAST CANADA AND A POTENTIAL GALE CENTER
PASSES SOUTHEAST OF 40N/70W BENCHMARK. A PERIOD OF SNOW WITH REDUCED
VSBY IS LIKELY WED ESPECIALLY OVER THE WATERS SOUTHEAST OF
NANTUCKET.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 7 AM THIS MORNING TO 1 PM EST
TUESDAY FOR ANZ230>237-251.
SMALL CRAFT ADVISORY FROM 7 AM THIS MORNING TO 7 PM EST
TUESDAY FOR ANZ250-254>256.
&&
$$
SYNOPSIS...NOCERA/DOODY
NEAR TERM...DOODY
SHORT TERM...DOODY
LONG TERM...NOCERA
AVIATION...NOCERA/DOODY
MARINE...NOCERA/DOODY
AREA FORECAST DISCUSSION
NWS TAUNTON MA
1241 AM EST MON FEB 24 2014
.SYNOPSIS...
A STRONG COLD FRONT CROSSES THE REGION TONIGHT...BRINGING
PROGRESSIVELY COLDER CONDITIONS THROUGH NEXT WEEKEND. MAINLY DRY
CONDITIONS WILL BE IN PLACE AS LARGE HIGH PRESSURE MOVES ACROSS.
ONE EXCEPTION WILL BE FOR THE RISK OF ACCUMULATING SNOWFALL FOR
WEDNESDAY AS LOW PRESSURE DEVELOPS WELL SOUTH OF NEW ENGLAND.
ANOTHER LOW MAY BRING SOME SNOWFALL NEXT WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
1 AM UPDATE...
BAND OF PRECIP CONTINUES TO WORK INTO CT AROUND MIDNIGHT WITH SOME
25-30 DBZ RETURNS APPARENT. HOWEVER...WITH DWPT DEPRESSIONS
REMAINING IN THE 10-15F RANGE...THESE ECHOS ARE LIKELY NOT
REACHING THE GROUND FOR THE MOST PART. OBS SITES ACROSS SRN NY DO
SHOW SOME LIGHT RAINFALL...BUT IT WILL LIKELY TAKE A BIT LONGER TO
CREEP INTO SRN NY. CURRENT HRRR SEEMS TO BE HANDLING THE PRECIP
CHANCES BEST SO POPS WERE TRENDED TOWARD ITS THINKING...SUGGESTING
A LIGHT BAND OF SN/RA MOVES ACROSS CT/RI/SE MA THROUGH ABOUT 12Z.
SHOULD PRECIP REMAIN LIGHT...MANY LOCATIONS MAY START AS RAIN OR
NEVER CHANGE OVER AT ALL...BUT CONTINUE SUGGEST SOME SNOWFALL IF
THE HIGHER DBZ ECHOS ARE ACTUALLY REACHING THE GROUND.
MEANWHILE THE COLD FRONT IS IN CENTRAL CT VALLEY AND THROUGH SRN
NH. SO IT IS CATCHING UP WITH THE PRECIP BAND. INCREASING THE
LIKELIHOOD FOR ENHANCED PRECIP AS THE NEAR SFC LIFT WILL BE
STRENGTHENED. IT WILL LIKELY FOLLOW THE FRONT OFFSHORE THROUGH 12Z
PER LATEST HRRR.
PREVIOUS DISCUSSION...
A STRONG COLD FRONT CROSSES THE REGION TONIGHT...BRINGING A
RETURN TO COLDER WEATHER. AT THE SAME TIME...A SHORTWAVE WILL
APPROACH FROM THE SOUTHWEST. THIS MAY BRING A BRIEF PERIOD OF
LIGHT PRECIP LATE TONIGHT...TO THE SOUTH OF THE MA TURNPIKE. THIS
DISTURBANCE ONLY CONTAINS A NARROW AXIS OF DEEP MOISTURE AND IS
FAIRLY PROGRESSIVE. THEREFORE...EXPECT PRECIP AMOUNTS TO BE QUITE
LIGHT. IN FACT...BOUNDARY LAYER IS INITIALLY WARM ENOUGH TO
SUPPORT LIGHT RAIN AT THE ONSET IN SOME AREAS BEFORE A CHANGE TO
LIGHT SNOW.
WITH ALL THAT SAID...A DUSTING TO MAINLY LESS THAN 1 INCH OF SNOW
IS POSSIBLE TO THE SOUTH OF THE MA TURNPIKE LATE TONIGHT. ANY
LIGHT SNOW WILL BE PRETTY MUCH DONE BY DAYBREAK...BUT A FEW SLICK
SPOTS WILL BE POSSIBLE FOR THE AM RUSH. LOW TEMPS BY DAYBREAK
MONDAY WILL MAINLY BE IN THE 20S...TO PERHAPS SOME LOWER 30S
ALONG THE FAR SOUTHEAST NEW ENGLAND COAST.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM TUESDAY/...
***MUCH COLDER AND WINDY WEATHER RETURNS ON MONDAY***
MONDAY...
A MUCH COLDER AND WINDY DAY FOLLOWS TONIGHT/S COLD FRONTAL PASSAGE.
HIGH TEMPS WILL ONLY RECOVER INTO THE UPPER 20S TO MIDDLE 30S...AS
NORTHWEST WINDS GUST TO BETWEEN 25 AND 35 MPH LATE IN THE
MORNING/AFTERNOON. WHILE A FAIR AMOUNT OF SUNSHINE IS EXPECTED
ALONG THE COASTAL PLAIN EARLY...A DECK OF SCATTERED TO BROKEN
DIURNAL CUMULUS CLOUDS WILL WORK ACROSS THE REGION FROM THE WEST AS
THE DAY WEARS ON. A BRIEF PASSING FLURRY/SNOW SHOWER OR TWO WILL
ALSO BE POSSIBLE...BUT THE INFILTRATION OF DRIER AIR WILL PROBABLY
PREVENT LOCALIZED HEAVIER SNOW SHOWERS/SQUALLS.
MONDAY NIGHT...
DRY...BUT COLD AND BLUSTERY WEATHER CONTINUES ACROSS SOUTHERN NEW
ENGLAND. NORTHWEST FLOW AND COLD ADVECTION WILL RESULT IN MOST
LOCATIONS BOTTOMING OUT IN THE TEENS BY DAYBREAK TUESDAY. WIND
CHILLS WILL DIP INTO THE SINGLE DIGITS ACROSS MOST OF THE REGION.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
HIGHLIGHTS...
* TEMPERATURES WILL STEADILY FALL AS ARCTIC AIR WORKS INTO THE
REGION THROUGH NEXT WEEKEND
* LOW PRESSURE PASSING SOUTH OF NEW ENGLAND WILL INCREASE CHANCES
FOR ACCUMULATING SNOWS WEDNESDAY
* ANOTHER LOW IS POSSIBLE DURING NEXT WEEKEND WHICH COULD BRING SOME
ACCUMULATING SNOW
OVERVIEW AND MODEL PREFERENCES...
MEDIUM RANGE MODELS AND ENSEMBLES CONTINUE TO SIGNAL DEVELOPMENT
OF LONGITUDINAL RIDGING ACROSS THE EASTERN PACIFIC TO ALASKA...
WHICH IN RETURN WILL BRING ANOTHER ROUND OF ARCTIC AIR FROM THE
NORTH POLE AND NORTHERN CANADA TOWARD THE CENTRAL AND EASTERN U.S.
WITH CUTOFF H5 LOW TAKING UP RESIDENCE NEAR HUDSON AND JAMES BAYS.
PRIOR TO THIS SETTING UP...NOTING A GOOD SHORT WAVE IN THIS FLOW
MOVING OUT OF SASKATCHEWAN AND MANITOBA EARLY TUE. THIS WILL CARVE
OUT A GOOD LONG WAVE TROUGH PROGRESSING E LATER TUE AND WED. AT
THE SURFACE...WILL SEE DEVELOPING LOW PRES CROSSING THE GREAT
LAKES WHILE ANOTHER SYSTEM WILL MOVE OUT OF THE NORTHERN GULF OF
MEXICO BY LATE TUE. THE SYSTEM REMAINS PROGRESSIVE...THOUGH WITH
THE COLD AIR IN PLACE...THERE IS A GOOD RISK FOR ACCUMULATING
SNOWS. SOME MODEL SPREAD NOTED ESPECIALLY WITH QPF VALUES AND HOW
FAR NORTH THESE PROGRESS. ALSO UNCERTAIN WHETHER THESE SYSTEMS
PHASE...THOUGH LAST SEVERAL RUNS HAVE SUGGESTED THEY REMAIN
SEPARATE WITH THE SOUTHERN LOW PASSING WELL SE OF THE 40N/70W
BENCHMARK.
BEYOND MID WEEK...HEART OF ARCTIC AIR SLOWLY WORKS S OUT OF
CENTRAL AND EASTERN CANADA...THOUGH COLDEST AIR DOES NOT LOOK TO
ARRIVE UNTIL LATE NEXT WEEK. H85 TEMPS PROGRESSIVELY DROP THROUGH
THE END OF THIS WEEK...AS LOW AS -15C TO -20C LATE THU AND FRI.
THIS TRANSLATES TO DAYTIME HIGHS STRUGGLING TO REACH FREEZING INTO
NEXT WEEKEND.
NOTING ANOTHER LOW WORKING OUT OF THE SOUTHERN PLAINS STATES LATE
NEXT WEEK THAT WILL TRY TO MOVE NE WHILE ANOTHER H5 SHORT WAVE
MOVES ACROSS THE GREAT LAKES DURING THIS WEEKEND. RATHER WIDE
MODEL SPREAD IN HOW THIS EVOLVES ALONG THE EASTERN SEABOARD. MAY
SEE ANOTHER ROUND OF PRECIP SOMETIME DURING THIS TIMEFRAME. THIS
LOOKS TO LEAD INTO NEAR RECORD LEVEL TEMPS FOR NEXT SUNDAY INTO
EARLY NEXT WEEK.
BASED ON THE MODEL TRENDS FOR COLDER CONDITIONS...USED THE COLDER
HPC GUIDANCE FOR TEMPS/DEWPTS FOR THE MID-LATE WEEK. MOS GUIDANCE
TENDS TO RUN CLOSER TO CLIMO THIS FAR OUT. AS FOR POPS...LEANED
TOWARD A GENERAL BLEND OF THE 00Z GFS/12Z AND 00Z EC ALONG WITH
THEIR ENSEMBLES.
DETAILS...
TUESDAY...DRY CONDITIONS BETWEEN SYSTEMS EXPECTED DURING THE DAY
TUE...THOUGH CLOUDS WILL INCREASE. EXPECT CHANCE POPS TO MOVE INTO
THE CT VALLEY AND S COAST WELL AFTER MIDNIGHT.
WEDNESDAY...LOW PRES PASSES WELL SE OF BENCHMARK WHILE WEAK
REFLECTION TO UPPER SYSTEM MOVES ALONG THE CANADIAN BORDER.
QUESTION IS HOW MUCH QPF WORKS N FROM THE SOUTHERN STREAM SYSTEM.
ECMWF LOOKS TO BE VERY BULLISH ON THIS...WHILE NAM IS WEAKEST.
WENT WITH A MIDDLE OF THE ROAD SOLUTION...WITH QPF VALUES OF 0.1
INCHES ACROSS S NH TO 0.25 TO 0.4 INCHES ALONG THE S COAST...CAPE
COD AND THE ISLANDS. LOOKS LIKE TEMPS AND THERMAL PROFILES FAVOR
ALL SNOW...SO COULD SEE DECENT ACCUMULATING SNOWFALL ALONG THE S
COAST. SOMETHING TO MONITOR CLOSELY...ESPECIALLY IF MORE QPF WORKS
NW FROM THE SOUTHERN LOW. DOES LOOK LIKE THE PRECIP SHOULD BE
PROGRESSIVE...SO PRECIP SHOULD EXIT WED NIGHT. W-NW WINDS BECOME
GUSTY LATE WED NIGHT AS LOW EXITS
THURSDAY AND FRIDAY...LARGE HIGH PRES BUILDS OUT OF CENTRAL AND
WESTERN CANADA...BRINGING FIRST BATCH OF ARCTIC AIR TO THE REGION.
EXPECT DRY AND COLD CONDITIONS. BRISK NW WINDS IN PLACE...GUSTS UP
TO 25 TO 30 MPH ALONG THE COAST AND ESPECIALLY CAPE COD AND THE
ISLANDS.
SATURDAY-SUNDAY...MODEL SPREAD LENDS TO LOW CONFIDENCE WITH THE
POSSIBLE APPROACH OF LOW PRES OUT OF THE SE U.S. LOW CHANCE OF
MORE ACCUMULATING SNOWS DURING THIS TIMEFRAME. ANOTHER SHOT OF
NEAR RECORD COLD AIR FOR EARLY MARCH IS ALSO POSSIBLE.
&&
.AVIATION /05Z MONDAY THROUGH FRIDAY/...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH TUESDAY/...
THROUGH 12Z...MODERATE CONFIDENCE.
A FEW LIGHT SNOW/RAIN SHOWERS WILL SKIRT CT/RI/SE MA TERMINALS.
LITTLE IF ANY ACCUMULATION IS EXPECTED...BUT THE BEST CHANCE WILL
BE ACROSS SE MA. MAINLY VFR...BUT A SHORT PERIOD OF MVFR
CONDITIONS ARE POSSIBLE IN ANY SHOWERS.
TODAY AND TUESDAY...HIGH CONFIDENCE.
MAINLY VFR THROUGH THE PERIOD...BUT SOME LOW CU BETWEEN 030-060
POSSIBLE THROUGH DAYLIGHT HOURS ALONG WITH SOME LIGHT SNOW
SHOWERS POSSIBLE MAINLY W OF A IJD-ORH-EEN LINE TODAY. NW WINDS
GUSTING 25-30 KT AT TIMES TODAY...W WINDS GUST 20-25 KT ON TUE.
KBOS TERMINAL...HIGH CONFIDENCE IN TAF.
KBDL TERMINAL...HIGH CONFIDENCE IN TAF.
OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...
WEDNESDAY...AREAS OF MVFR-IFR CONDITIONS IN SNOW DURING THE DAY.
EXPECT IMPROVING CONDITIONS FROM W-E LATE WED INTO EARLY WED
NIGHT. VFR LATE. GUSTY W-NW WINDS DURING WED NIGHT...HIGHEST ALONG
COAST.
THURSDAY...VFR CONDITIONS. GUSTY NW WINDS.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
TONIGHT...HIGH CONFIDENCE. SOUTHWEST WINDS SHIFT TO THE NORTHWEST
BEHIND A COLD FRONT. GUSTS UP TO 25 KNOTS MAY DEVELOP TOWARDS 12Z
AS COLD AIR ADVECTION GETS UNDERWAY. MAY ALSO SEE VISIBILITIES
REDUCED BRIEFLY TO BETWEEN 1 AND 3 MILES BETWEEN 6Z AND 12Z IN A
PERIOD OF LIGHT RAIN/SNOW SHOWERS.
MONDAY AND MONDAY NIGHT....HIGH CONFIDENCE. NORTHWEST WIND GUSTS OF
25 TO 30 KNOTS EXPECTED UNDER STRONG COLD ADVECTION YIELDING
EXCELLENT MIXING OVER THE OPEN WATERS. LOW PROBABILITY THAT A FEW
AREAS BRIEFLY SEE GUSTS NEAR 35 KNOTS...BUT IT WOULD BE TOO BRIEF
AND NOT WIDESPREAD ENOUGH FOR GALES. HOWEVER...SCA ADVISORIES ARE
POSTED FOR ALL WATERS MONDAY AND MONDAY NIGHT. LIGHT FREEZING
SPRAY IS EXPECTED TO DEVELOP MONDAY NIGHT UNDER STRONG COLD
ADVECTION.
OUTLOOK...TUESDAY THROUGH FRIDAY...
TUESDAY...W-NW WINDS GUSTING TO 25-30 KT WITH SEAS AOA 5
FT...DIMINISHING TUE NIGHT. VSBYS LOWER ON SOUTHERN WATERS AFTER
MIDNIGHT IN SNOW.
WEDNESDAY...NW WINDS INCREASE...GUSTING UP TO 30 KT ON THE OUTER
WATERS. SEAS BUILD UP TO 7 FT. LIGHT TO MODERATE FREEZING SPRAY
LIKELY WED NIGHT. VSBY RESTRICTIONS IN SNOW AND PATCHY FOG.
THURSDAY...NW WINDS GUSTING UP TO 30 KT THU...THEN SLOWLY DIMINISH
THU NIGHT. SEAS UP TO 8 FT WITH LIGHT TO MODERATE FREEZING SPRAY
LIKELY INTO THU NIGHT.
FRIDAY...WINDS AND SEAS DIMINISH.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 7 AM THIS MORNING TO 5 AM EST
TUESDAY FOR ANZ230>237-250-251-254>256.
&&
$$
SYNOPSIS...FRANK/EVT
NEAR TERM...FRANK/DOODY
SHORT TERM...FRANK
LONG TERM...EVT
AVIATION...DOODY/EVT
MARINE...FRANK/EVT
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1203 AM EST MON FEB 24 2014
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 435 PM EST SUN FEB 23 2014
THE UPPER GREAT LAKES REGION IS UNDER THE INFLUENCE OF A UPPER
LOW SPINNING OVER EASTERN ONTARIO AT THIS TIME. THIS UPPER LOW HAS
BEEN ROTATING MID LEVEL MOISTURE SOUTHEAST ACROSS THE REGION TODAY
AS SEEN IN WATER VAPOR IMAGERY AND REPRESENTED ON THE 12Z KINL
SOUNDING. WITH THE OPEN WATER OVER PORTIONS OF WESTERN LAKE
SUPERIOR...MOISTURE FROM THE UPPER LOW...AND RAP ANALYZED 850MB
TEMPS AROUND -22C...HAVE BEEN SEEING LAKE CLOUDS AND LIGHT SNOW
SHOWERS ON WEBCAMS AND SATELLITE OVER NORTHERN ONTONAGON...HOUGHTON
AND KEWEENAW COUNTIES. THERE WAS ONE STRONGER BAND THAT STRETCHED
FROM NORTHERN HOUGHTON COUNTY TO JUST NORTH OF GRAND MARAIS. WHERE
THE RADAR CAN SAMPLE IT IT WAS INDICATING SNOWFALL RATES AROUND
0.5-1 INCH AN HOUR SOUTH EAST OF STANNARD ROCK WHERE IT HAS BEEN
AIDED BY ANOTHER AREA OF OPEN WATER. AS WINDS HAVE BEEN SLOWLY
SHIFTING TO THE NORTHWEST...THIS BAND HAS BEEN SHIFTING SOUTH
THROUGH THE DAY...BUT DID GET A REPORT FROM WHITEFISH POINT OF AN
ESTIMATED 6-8 INCHES OF SNOW. WOULD EXPECT AMOUNTS THAT HIGH IN
NORTHERN LUCE COUNTY WITH THE MOVEMENT BUT THINK AMOUNTS IN THE 1-3
INCH RANGE ARE REASONABLE SINCE THIS MORNING.
AS THE UPPER TROUGH AND SURFACE LOW SHIFT EAST TONIGHT...IT WILL
SWEEP A WEAK SHORTWAVE AND SFC-850MB TROUGH SOUTHEAST ACROSS LAKE
SUPERIOR. THESE TROUGHS WILL ACT TO PROVIDE MORE LOW LEVEL MOISTURE
OVER THE REGION TONIGHT INTO MONDAY MORNING AND TURN THE LOW LEVEL
WINDS TO THE NORTHWEST. 850MB TEMPS OF -23C WILL LEAD TO PLENTY OF
OVER THE LAKE INSTABILITY WHERE THERE IS OPEN WATER (INVERSION
HEIGHTS TO 6-7KFT). THERE IS A LITTLE BIT OF AN UNCERTAINTY ON
THE ICE COVERAGE...BUT BASED OFF YESTERDAY/S MODIS IMAGE AND
LOCATION OF LAKE CLOUDS TODAY...IT APPEARS THERE IS DECENT OPEN
WATER FROM TWO HARBORS MINNESOTA TO ISLE ROYALE...THEN
EAST-NORTHEAST OF ISLE ROYALE TO NORTHERN LAKE SUPERIOR AND ALSO TO
THE EAST OF THE KEWEENAW AND TOWARDS MARQUETTE. WHERE ICE CAN BE
MADE OUT...THERE HAS BEEN DECENT MOVEMENT WITH THE WEST-NORTHWEST
WINDS OF 20-30KTS. WITH WEAKENING WINDS INCREASING THE RESIDENCE
TIME OVER THE 20-30MI AREA OF OPEN WATER OVER THE WEST
TONIGHT...THINK THAT WILL BE ENOUGH FOR LIGHT AND OCCASIONALLY
MODERATE LAKE EFFECT SNOWS TO OCCUR FROM CALUMET SOUTHWEST TO
IRONWOOD AND WILL CONTINUE TO SHOW LIKELY AND LOW DEFINITE POPS
FOR THOSE AREAS TONIGHT. NORTH OF CALUMET IS A LITTLE UNCERTAIN ONCE
WINDS TURN TO THE NORTHWEST DUE TO MORE ICE BETWEEN ISLE ROYALE AND
THUNDER BAY AND SMALLER GAPS IN THE FIRST 10-15MI SOUTHEAST FROM
ISLE ROYALE. THEREFORE...WILL HAVE THE POPS LOWER INTO THE LOW END
LIKELY CATEGORY ONCE THE WINDS TURN TO THE NORTHWEST.
OVERALL...SNOWFALL AMOUNTS SHOULD BE LIGHT AND IN THE 1-4 INCH
RANGE. GUSTY THIS EVENING (TO 35MPH)...BUT WITH THE LOW WEAKENING
AND SHIFTING EAST TONIGHT...SHOULD SEE A GRADUAL DIMINISHING TREND
TO THE WINDS. THIS WILL LEADING TO IMPROVING VISIBILITIES FROM THE
BLOWING SNOW OVER THE KEWEENAW PENINSULA. SINCE WE ARE STILL
GETTING REPORTS FROM OBS/WEBCAMS/SPOTTERS OF VISIBILITIES BELOW
1/2MI AT TIMES...DECIDED TO EXTEND THE ADVISORY UNTIL MIDNIGHT.
THIS WILL COVER THE EVENING TRAVEL PERIOD BEFORE THE WINDS DIMINISH
OVERNIGHT.
FARTHER EAST...THE MAIN AREA OF CONCERN WILL BE OVER NORTHERN
LUCE AND THEN TRANSITIONING INTO ALGER COUNTY DUE TO THE FAVORABLE
FETCH ACROSS THE OPEN WATER THAT LIKELY COVERS A DECENT PORTION OF
LSZ265. WITH NORTHWEST WINDS AND PROBABLY SOME LAND BREEZE
INFLUENCE...WOULD THINK THERE WOULD BE SOME ENHANCED LAKE EFFECT
BAND AFFECTING THE COUNTY AND GRADUALLY TRANSITIONED THE BAND
SOUTHWEST THIS EVENING TO AROUND AND JUST EAST OF MUNISING AREA
OVERNIGHT. WITH A POTENTIAL FETCH OF 80MI AND SOME UPSTREAM
MOISTENING OVER THE WESTERN LAKE...WOULDN/T BE SURPRISED IF THERE
ARE SOME LOCALIZED 4 INCH AMOUNTS ESPECIALLY IF THE BAND STALLS IN
AN AREA FOR A FEW HOURS. EAST OF THERE...THE AMOUNT OF ICE COVERAGE
WILL LIKELY LIMIT AMOUNTS AND ONLY HAVE VALUES IN THE 1 TO MAYBE 2
INCH RANGE.
WILL START TO SEE THE AFFECT OF RIDGING UPSTREAM THROUGH THE DAY
TOMORROW AS THE UPPER LOW SHIFTS EAST. THIS WILL LEAD TO INCREASING
850MB TEMPERATURES (ALONG WITH SOME DRYING AND BACKING WINDS) FROM
WEST TO EAST...ESPECIALLY IN THE AFTERNOON. THUS...WILL FOLLOW THAT
TREND FOR POPS AND SNOWFALL AMOUNTS THROUGH THE DAY. HIGHS TOMORROW
WILL BE IN THE LOW-MID TEENS OVER MUCH OF THE AREA. THIS LOOKS TO
BE THE WARMEST HIGHS FOR THE REST OF THE WORK WEEK.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 435 PM EST SUN FEB 23 2014
THE CWA WILL BE DOMINATED BY LOW WIND CHILLS...AND LIGHT TO MODERATE
LES FOR AREAS DOWNWIND OF W TO NW FLOW OVER GAPS IN THE CONSIDERABLE
LAKE ICE COVER.
MON NIGHT...THE STRONGEST 850-500 MB QVECTOR CONV AND
LOWER LEVEL WAA/ISENTROPIC LIFT ASSOCIATED WITH THE FIRST IN A SERIES
OF SHORTWAVE TROUGHS IS EXPECTED TO REMAIN WELL TO THE SOUTH THROUGH
IA INTO SRN WI AND NRN IL. WRLY FLOW LES BANDS WILL SHIFT SLIGHTLY AS
WINDS VEER TO WNW BEHIND A WEAK SFC TROUGH. WITH CONTINUED
UNCERTAINTY ON THE EXTENT OF OPEN WATER AND INVERSION HEIGHTS ONLY
AROUND 5K FT...MENTIONED LIKELY POPS BUT WITH FCST SNOWFALL AMOUNTS
ONLY OF AROUND AN INCH OR TWO.
TUE INTO TUE NIGHT...THE MODELS SUGGEST ANOTHER SHRTWV WITH AN ARCTIC
FRONT BRINGING IN EVEN COLDER AIR WILL MOVE THROUGH BY LATE TUE INTO
TUE NIGHT. WINDS WILL VEER TO THE NW PUSHING THE LIGHT LES OVER A
GRATER PORTION OF THE ERN CWA. WITH MIN TEMPS DROPPING INTO THE -4F
TO -14F RANGE...WIND CHILLS SHOULD ALSO FALL INTO THE -20 TO -30
RANGE.
WED-FRI...A STRONGER SHRTWV WILL MOVE THROUGH THE NRN LAKES AS THE
POLAR TROUGH MOVES INTO NRN ONTARIO. WINDS ARE EXPECTED TO VEER TO
THE NW TO NNW BEHIND THIS FEATURE AS 850 MB TEMPS DROP TO AROUND
-31C THU. WITH THE STRONGER NW WINDS...THE LOWEST WIND CHILLS ARE
EXPECTED THU MORNING INTO THE -25 TO -35 RANGE EVEN THOUGH THERE MAY
SOME MODIFICATION OVER THE MOSTLY FROZEN LAKE. WITH LIGHTER WINDS
AND FEW CLOUDS BY FRI AS THE ARCTIC HIGH SETTLES OVER THE
AREA...TEMPS SHOULD DROP AT LEAST INTO THE -15 TO -25 RANGE OVER
MUCH OF THE CWA...WITH SOME -30S EVEN POSSIBLE FOR TRADITIONAL COLD
SPOTS.
SAT-SUN...THERE IS GREATER UNCERTAINTY WITH ANY INDIVIDUAL SHRTWVS
BUT WITH THE POLAR TROUGH LINGERING NEAR JAMES BAY...ANOTHER BOUT OF
LOWER 850 MB TEMPS AND HIGHER WINDS MAY MOVE IN BY SAT WITH
DIMINISHING WINDS AND CONTINUED COLD ON SUN WITH THE ARCTIC RIDGE
DOMINATING THE NRN LAKES. BY THE WEEKEND...THE ICE COVER IS LIKELY
TO SOLIDIFY...REDUCING LES CHANCES/AMOUNTS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1203 AM EST MON FEB 24 2014
WITH LIGHTER NW WINDS AND LESS BLSN...EXPECT MVFR CONDITIONS TO
PREVAIL THRU THE FCST PERIOD AT KCMX. HOWEVER...WITH OCNL LAKE
EFFECT -SHSN...THERE WILL LIKELY BE SOME PERIODS OF IFR CONDITIONS
AS WELL. DISTURBANCE CROSSING THE AREA THIS EVENING COULD BRING MORE
SUSTAINED IFR VIS.
AT KIWD...LAKE EFFECT -SHSN AND IFR CONDITIONS HAVE DEVELOPED AS
EXPECTED DUE TO WINDS VEERING MORE TO THE NW. IFR CONDITIONS SHOULD
PREVAIL OVERNIGHT INTO THE EARLY MORNING. THEREAFTER...THERE SHOULD
BE SOME IMPROVEMENT BACK TO MVFR BY LATE MORNING AS DEEPER MOISTURE
EXITS. CONDITIONS MAY IMPROVE TO VFR AT TIMES DURING THE
AFTN/EVENING.
AT KSAW...DOWNSLOPE NATURE OF THE W TO NW FLOW HAS RESULTED IN
CONDITIONS REMAINING VFR. HOWEVER...WITH INCREASE IN LOW-LEVEL
MOISTURE...HIGH MVFR CIGS SHOULD STILL DEVELOP OVERNIGHT...THEN LIFT
TO VFR THIS AFTN.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 435 PM EST SUN FEB 23 2014
THE WEAKENING LOW NEAR HUDSON BAY WILL COMBINE WITH A HIGH PRESSURE
RIDGE MOVING THROUGH THE NORTHERN PLAINS AND MID MISSISSIPPI VALLEY
TO LEAD TO GRADUALLY DECREASING WEST TO NORTHWEST WINDS OVER LAKE
SUPERIOR TONIGHT THROUGH MONDAY NIGHT. HAVE BEEN SEEING THE GALES
PERSISTING OVER THE EASTERN PART OF LAKE SUPERIOR ON THE STANNARD
ROCK AND GRANITE ISLAND OBS THIS AFTERNOON...BUT WITH UPSTREAM OBS
GENERALLY IN THE 30KT RANGE...WOULD EXPECT THE EASTERN SITES TO
COME DOWN SHORTLY. THUS...WILL ALLOW THE GALE WARNING OVER THE
EASTERN LAKE TO EXPIRE AT 00Z AND HAVE ALREADY CANCELLED THE
WESTERN LAKE. EVEN WITH THIS DIMINISHMENT...THERE WILL LIKELY BE
ENOUGH OF A GRADIENT TO KEEP WINDS IN THE 15 TO 30KT RANGE FOR MUCH
OF THE FORECAST PERIOD.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...JLB
AVIATION...ROLFSON
MARINE...SRF
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
350 AM CST MON FEB 24 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 350 AM CST MON FEB 24 2014
1038 MB ARCTIC HIGH PRESSURE ACROSS SRN ALBERTA AND SRN
SASKATCHEWAN WILL MOVE INTO SOUTH DAKOTA BY 12Z TUESDAY MORNING.
AN ARCTIC FRONT ACROSS NRN MT IS EXPECTED TO MOVE INTO THE FCST
AREA BY LATE AFTN AND BE THROUGH THE FCST AREA AND ACROSS KS BY
TUESDAY MORNING. LOWS IN THE SINGLE DIGITS ARE EXPECTED TONIGHT
WITH WIND CHILL READINGS AROUND 10 BELOW TO PERHAPS 15 BELOW ZERO
ACROSS NORTHERN NEB.
THE MODEL CONSENSUS SUGGESTS A PERIOD OF LIGHT SNOW
DEVELOPING...MAINLY ACROSS WRN NEBRASKA...AS THE FRONT MOVES
THROUGH. SNOWFALL AMOUNTS SHOULD BE LESS THAN AN INCH AND MAINLY
A DUSTING.
THERE IS QUITE A VARIETY OF MAX TEMPERATURE FORECASTS TO CHOOSE
FROM TODAY. THE FORECAST FOLLOWS A BLEND OF NAM...GEM REG...ECM
AND MET PLUS BIAS CORRECTION FOR HIGHS IN THE UPPER 20S NORTH TO
UPPER 30S SOUTH. THE NAM IS ACTUALLY FORECASTING MID 40S AT NORTH
PLATTE WHILE THE RAP SHOWS UPPER 20S AND THE ECM MID 30S. THIS IS
A FUNCTION OF THE SKY COVER INDICATED IN THE MODELS AND SOME
SOLNS SHOW A PERIOD OF CLEARING AHEAD OF THE ARCTIC FRONT. THE
MODEL CONSENSUS SUGGESTS CLEARING ACROSS WRN/SWRN
NEB...KAIA-KOGA-KIML AS A RESULT OF SOME SOUTHWEST WINDS
DEVELOPING. EAST OF THAT AREA IT LOOKS LIKE ARCTIC DRAPE SHOULD
CONTINUE WITH SOUTH WINDS.
THE LIGHT TO MODERATE SNOW ON RADAR EARLY THIS MORNING ACROSS
NCNTL NEB IS MOVING RAPIDLY EAST AND SHOULD BE REPLACED BY A
SECOND AREA OF SNOW LATER THIS MORNING A BIT FARTHER NORTH AND
EAST. THIS SNOW IS CURRENTLY SHOWING ON THE KUNR RADAR ACROSS WRN
SD. THE MODELS GENERATE A THIRD AREA OF SNOW THIS AFTERNOON BUT
THIS SHOULD PASS MOSTLY NORTH AND EAST OF THE FORECAST AREA. THIS
AREA OF SNOW IS CURRENTLY ACROSS SERN MT.
BEST SNOWFALL IS EXPECTED ACROSS BOYD COUNTY WITH QPF RANGES FROM
LESS THAN 0.10 INCHES IN THE UKMET...GEF AND GFS TO 0.30 INCHES
IN THE NMM WEST. THIS IS A WIDE RANGE AND THE CONSENSUS IS AROUND
0.15 INCHES. A 15 TO 20 TO 1 SNOW RATIO WAS USED BASED ON THE
COBB METHODOLOGY. OBSERVED SNOWFALL SUNDAY AFTN AND SUNDAY NIGHT
WAS IN THIS RANGE. THE NAM CONTINUES TO ADVERTISE POCKETS OF
STRONG FRONTOGENESIS WHICH COULD LEAD TO BANDED SNOW DEVELOPMENT.
THIS HAS BEEN THE OPERATIVE MODE IN MANY INSTANCES OVER THE PAST
36 HOURS HOWEVER THE NAM...ARF AND NMM MODELS HAVE SHOWN POOR
SKILL FORECASTING THE LOCATION OF THESE BANDS.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 350 AM CST MON FEB 24 2014
TEMPS FOR THE END OF FEBRUARY AND INTO MARCH WILL BE DOMINATED BY
COLD ARCTIC AIR WITH WELL BELOW NORMAL READINGS. WEDNESDAY LOOKS
TO BE THE ONLY DAY WE MAY BE WITHIN 10 DEGREES OF NORMAL FOR
HIGHS INTO THE NEXT WEEKEND. ALSO WILL SEE AN ACTIVE PERIOD WITH
SEVERAL CHANCES FOR SNOW THROUGHOUT THE WEEK AND INTO THE
WEEKEND.
TUESDAY WILL SEE ANOTHER DISTURBANCE DRIFTING ACROSS THE SW
PORTIONS OF THE CWA. BATTLE WILL BE BETWEEN RADIATION OF A HIGHER
LATE FEBRUARY SUN ANGLE AND SNOWFALL RATES...ON TOP OF A SNOW
PACK. PLOWED ROADS TODAY FOR THE MOST PART BECAME WET AND IN SOME
AREAS EVEN PARTIALLY DRIED...DESPITE CLOUDY SKIES. THINK CLOUDS
WILL BE THICKER LIMITING SOLAR IMPACT...HOWEVER MODELS ARE ONLY
PRODUCING LIGHT SNOW. DAYTIME SNOW OF A HALF INCH TO 1.5 INCHES
FOR THE MOST PART WITH A 15 TO 1 RATIO...HIGHEST ACROSS THE
SOUTHEASTERN PAN HANDLE AND SW NEB.
BY TUESDAY NIGHT ARCTIC HIGH PRESSURE WILL BE DRIFTING OVERHEAD.
CENTER CROSSES OVER THE CWA BETWEEN 04Z AND 09Z. BY 12Z THE HIGH
WILL BE TO THE SE WITH SOUTHWESTERLY WINDS TO BE ON THE
INCREASING...ALONG WITH WAA. LOWS INITIALLY EXPECTED WITH THE
CENTER OF THE HIGH OVERHEAD...EARLY IN THE NIGHT...HOWEVER WITH
THE EXPECTED SNOW PACK...DECOUPLING WILL KEEP WINDS FROM MIXING TO
THE GROUND UNTIL SUNRISE OR LATER. THIS MAY ALLOW A COUPLE OF
DEGREES FURTHER OF A DROP AFTER CENTER PASSES. EITHER
WAY...EXPECT LOWS TO FALL TO A FEW DEGREES ON EITHER SIDE OF ZERO.
WITH THE WAA FOR WED...HIGHS WILL REBOUND ABOVE FREEZING. WARMEST
GUIDANCE IS INTO THE 40S...HOWEVER THINK SNOW PACK WILL HOLD HIGHS
IN THE 30S.
NEXT COLD FRONT ARRIVES FOR THURSDAY WITH TEMPS TO TAKE A
DOWNWARD TREND. A COUPLE OF REINFORCING COLD FRONT WILL CONTINUE
TO TAKE TEMPS LOWER INTO THE WEEKEND. THIS WILL BE COUPLED WITH
SEVERAL DISTURBANCE TO RIDE ACROSS THE HIGH PLAINS WITH SEVERAL
CHANCES FOR SNOW. SNOW IS NOT EXPECTED TO BE CONSTANT...HOWEVER
CHANCES FOR AT LEAST LIGHT SNOW IN ANY 12 HOURS PERIOD WILL
RESULT IN MANY PERIODS WITH SNOW IN THE FORECAST.
NORMAL HIGHS THIS TIME OF YEAR SHOULD BE INTO THE 40S WITH LOWS
IN THE TEENS. MODELS ARE IN GOOD AGREEMENT WITH HIGHS ONLY IN THE
10S AND 20S FROM FRIDAY THROUGH THE WEEKEND AS THE COLD AIR
BLANKETS MUCH OF THE CONUS. COLDEST GUIDANCE IS THE EC WITH MANY
LOCATIONS NOT WARMING ABOVE SINGLE DIGITS FOR THE WEEKEND. THIS
IS NEARLY 40 DEGREES BELOW NORMAL. SUN ANGLE CONTINUES TO
INCREASE...AND RECORD LOW MAXES ARE IN THE SINGLE DIGITS...SO DO
NOT WANT TO GO WITH THE RECORD COLD FROM THE EC YET...THUS
FORECAST IS FAVORING A SLIGHTLY WARMER GFS AT THIS TIME. HOWEVER
WILL CONTINUE TO KEEP AN EYE ON THIS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1127 PM CST SUN FEB 23 2014
SURFACE WIND AND THE FIRST 1000M ABOVE THE SURFACE SHOW SOUTHEAST
WIND WHICH IS UPSLOPE. THE RESULT IS STRATUS WITH CEILING 1000
FEET AGL OR LOWER. THERE IS SOME UNCERTAINTY REGARDING HOW FAR
EAST IT WILL SPREAD. THE TERRAIN WOULD INDICATE THAT THE LOW
CEILINGS WOULD REACH TO JUST WEST OF VTN-TIF-LBF. STILL...IT WILL
BE CLOSE ENOUGH TO THOSE SITES TO JUSTIFY INCLUDING AT LEAST AN
INTERMITTENT CONDITION OF CEILING BELOW 1000 FEET AGL.
THE SNOW BANDS INDICATED ON RADAR ARE LIKELY TO STAY BETWEEN VTN
AND LBF. HOWEVER...THE HEAVIER SNOW WILL CONTINUE AT TIF...MHN AND
BBW UNTIL ABOUT 10Z WHEN THE CONDITIONS BECOME LESS FAVORABLE FOR
BANDED MODERATE TO HEAVY SNOW.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...MASEK
AVIATION...SPRINGER
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1135 PM CST SUN FEB 23 2014
.UPDATE...
ISSUED AT 1135 PM CST SUN FEB 23 2014
NO CHANGES PLANNED TO LATE EVENING UPDATE. FORECAST LOOKS IN GOOD
SHAPE FOR EARLIER DECISION OF DELAYING WIND CHILL HEADLINES UNTIL
12 AM CST. DVL BASIN AREA NOW WELL WITHIN CRITERIA...WITH THE
NORTHERN VALLEY NEARING 25 BELOW. LAKE OF THE WOODS STILL QUITE
WARM BUT CLOUD COVER OVER AREA EXPECTED TO MOVE EAST IN THE 06Z TO
08Z TIMEFRAME.
UPDATE ISSUED AT 955 PM CST SUN FEB 23 2014
MAIN CHALLENGE FOR TONIGHT IS INHERITED WIND CHILL HEADLINES.
WARMEST TEMPS AS OF RIGHT NOW ARE OVER SOUTHEASTERN ND...AND
MODELS SHOWING RANSOM/SARGENT HAVING LIGHTEST WINDS TONIGHT AS
WELL (ALREADY AROUND 5KTS). WILL REMOVE THESE TWO COUNTIES FROM
ADVISORY AS WIND CHILLS ARE NOT EXPECTED TO REACH CRITERIA.
FOR THE REST OF THE AREA...WIND CHILLS NEARING CRITERIA WHERE
BREEZY WINDS ARE STILL GOING OVER NORTHEASTERN ND. EXPECT APPARENT
TEMPS IN THIS AREA TO WARM UP A BIT AS WINDS DIE DOWN...THEN BEGIN
FALLING AGAIN IN THE 06Z TO 09Z TIMEFRAME ALONG WITH THE REST OF
THE CWA. DELAYED COUNTIES OUTSIDE OF NORTHEASTER ND/NORTHERN RRV
UNTIL 12 AM BUT 3 AM IS THE MORE LIKELY TIMEFRAME FOR MEETING
ADVISORY CRITERIA. THIS WILL MATCH UP NICELY WITH NEIGHBORING WFOS
TO THE EAST AND SOUTH. NO OTHER CHANGES MADE TO THIS FCST.
FOR TOMORROW...THE LATEST NAM AND RUC CONTINUE TO BRING PRECIP
INTO THE SOUTHWESTERN ZONES AFTER NOON TIMEFRAME...WITH THE RUC
HAVING DRIER QPFS. LOOKS LIKE MOST SNOW SHOULD BE SOUTH OF THE HWY
200 CORRIDOR OR PERHAPS EVEN THE I 94 CORRIDOR. NO CHANGES TO POPS MADE.
UPDATE ISSUED AT 656 PM CST SUN FEB 23 2014
CLEAR SKIES ACROSS CWA TONIGHT...WITH WINDS STILL IN THE 15 TO 25
MPH RANGE FOR MUCH OF THE AREA. OVER THE NEXT COUPLE OF
HOURS...WINDS SHOULD BEGIN TO DIE OFF ENOUGH TO ALLOW TEMPS TO
BEGIN TO FALL YET HIGH ENOUGH TO BRING WIND CHILLS IN THE 25 BELOW
TO 35 BELOW RANGE. NO PLANNED CHANGES TO HEADLINES TONIGHT.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 325 PM CST SUN FEB 23 2014
CHALLENGES INCLUDE WIND CHILLS TONIGHT AND LOW PRECIPITATION
CHANCES TOMORROW. GLOBAL MODELS ARE IN GOOD AGREEMENT AND WILL USE
A BLENDED SOLUTION.
FOR TONIGHT...SCT-BKN CLOUD COVER WILL REMAIN CONFINED TO THE
NORTHEAST FORECAST AREA AS CLOUD DECK AROUND JAMES BAY LOW
CONTINUES TO PIVOT TO THE SOUTH. ALL OTHER AREAS WILL REMAIN
MOSTLY CLEAR AS SURFACE RIDGE BUILDS ACROSS EASTERN ND INTO
SOUTHWEST MN. CURRENT TEMPERATURES UNDER THIS RIDGE ARE IN THE
SINGLE DIGITS BELOW ZERO ACROSS ALBERTA AND SOUTHERN SASKATCHEWAN
AND THIS COLDER AIR MASS WILL BEGIN TO SAG SOUTHWARD OVERNIGHT.
NORTHWEST WIND WILL REMAIN ELEVATED BETWEEN 5 AND 10 MPH...BUT
TEMPERATURE GUIDANCE IN FAIR AGREEMENT SHOWING OVERNIGHT LOWS
DROPPING INTO THE LOW TEENS BELOW ZERO. AIR TEMPERATURES AND WINDS
WILL RESULT IN WIND CHILL VALUES FROM 25 TO 35 BELOW...SO WILL
ISSUE A CWA-WIDE WIND CHILL ADVISORY FROM 04 UTC TONIGHT UNTIL 16
UTC MONDAY.
SURFACE LOW WILL DIVE SOUTH ALONG THE LEE OF THE ROCKIES ON MONDAY
WITH WARM AIR ADVECTION SNOW DEVELOPING MAINLY ACROSS SD. NORTHERN
EXTENT OF THIS SNOW SHIELD MAY CLIP THE SOUTHERN FORECAST AREA...
SO WILL KEEP CHANCE POPS MAINLY ALONG AND SOUTH OF THE I-94/HWY 10
CORRIDOR. WAS ABLE TO REMOVE POPS MONDAY MORNING WITH SLOWER
FORWARD PROGRESSION IN THE MODELS. ANY ACCUMULATION WILL BE
MINIMAL...AROUND A HALF INCH OR LESS. TEMPERATURES TO BE A BIT
COOLER THAN TODAY...BUT STILL ABOVE ZERO WITH NORTHWEST WIND
BETWEEN 5 AND 15 MPH.
LINGERING SNOW SHOWERS POSSIBLE ACROSS SOUTHEAST FORECAST AREA
MONDAY NIGHT...WITH ALL OTHER AREAS DRY. MOSTLY CLEAR SKIES...
TEMPERATURES BELOW ZERO AND WIND AROUND 10 MPH WILL LIKELY
NECESSITATE ANOTHER WIND CHILL ADVISORY.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 325 PM CST SUN FEB 23 2014
MORE OF THE SAME FOR TUESDAY AND WEDNESDAY AS 1035 TO 1040 HPA
SURFACE HIGH DROPS SOUTH FROM CANADA AND MOVES ACROSS THE NORTHERN
PLAINS. EXPECT MORE SUN THAN CLOUDS WITH PERSISTENT BREEZY
CONDITIONS FROM THE WEST-NORTHWEST. HIGH TEMPERATURES TUESDAY
AROUND THE ZERO MARK WILL WARM SLIGHTLY BY WEDNESDAY INTO THE
SINGLE DIGITS TO MID TEENS ABOVE ZERO. THE SEEMINGLY ENDLESS
STREAM OF WIND CHILL ADVISORIES WILL MOST LIKELY CONTINUE BOTH
TUESDAY AND WEDNESDAY NIGHT.
LONG RANGE MODELS CONTINUE TO ADVERTISE THE COLD POOL OF AIR SITTING
OVER CENTRAL CANADA INTO HUDSON BAY REGION DOWN INTO THE NORTH
CENTRAL UNITED STATES. SURFACE HIGH REMAINS FROM NORTH DAKOTA
INTO SASK. THUS FOR THE THURSDAY THROUGH SUNDAY PERIOD EXPECTING
WELL BELOW NORMAL TEMPERATURES BUT DRY CONDITIONS. MAY BE A LITTLE
LOW ON THURSDAY FEATURING RIDICULOUSLY COLD MAX TEMPS BUT LET RIDE
FOR NOW. ADDED A COUPLE OF DEGREES TO WEEKEND TEMPS...IF ECMWF IS
CORRECT IT WILL BE COLDER THOUGH AS IT ROTATES COLD POOL FROM
NORTHERN MANITOBA THROUGH WINNIPEG INTO MINNESOTA. FORECAST STILL
BARREN WITH RESPECT TO PRECIPITATION THROUGH SATURDAY WITH A SOUTH
TRACKING SYSTEM OFFERING SCANT POPS ACROSS THE FAR SOUTHWEST
BRIEFLY ON SUNDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1135 PM CST SUN FEB 23 2014
VFR CONDS ACROSS AREA THROUGH 06Z TAF PERIOD...WITH EXCEPTION OF
FAR. MAY SEE SOME MVFR CIGS AND LIGHT SNOW IN THE LATE AFTN TO
EARLY EVENING HOURS TOMORROW. DID MENTION LIGHT SNOW AFT 22Z AS
MODELS HAVE CONSISTENTLY BROUGHT PRECIP ALONG AND SOUTH OF I 94
CORRIDOR. HAVE MAINTAINED LOW VFR CIGS AT DVL AND GFK BUT REMOVED
CIGS FROM TVF AND BJI AS SWATH OF CLOUDS SHOULD DROP SOUTH AS THEY
DRIFT EAST.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...WIND CHILL ADVISORY UNTIL 10 AM CST MONDAY FOR NDZ038-039-053.
WIND CHILL ADVISORY UNTIL 10 AM CST MONDAY FOR NDZ006>008-
014>016-024-026>030-054.
MN...WIND CHILL ADVISORY UNTIL 10 AM CST MONDAY FOR MNZ003-005-006-
008-009-013>017-022>024-027>032-040.
WIND CHILL ADVISORY UNTIL 10 AM CST MONDAY FOR MNZ001-002-004-
007.
&&
$$
UPDATE...SPEICHER
SHORT TERM...ROGERS
LONG TERM...ROGERS/WJB
AVIATION...SPEICHER
AREA FORECAST DISCUSSION
NWS SPOKANE WA
1023 PM PST Sun Feb 23 2014
.SYNOPSIS...
Periods of snow will continue tonight. Snow showers will linger
through Monday, mainly over the Cascades, Blue Mountains, and the
Idaho Panhandle. A subtle warming trend is expected Tuesday
through Thursday with temperatures near average for the second
half of the work week. Next weekend has the potential to be colder
with a chance of more snow.
&&
.DISCUSSION...
Ended some of the winter weather advisories, decreased pops in
those same areas, and slightly cooled forecast low temperatures
tonight with a late evening update. Radar and HRRR runs suggest
the back edge of the exiting swath of snowfall is slowly moving to
the southeast and exited those area to the north. Some light
precipitation may still fall on those locations but since no
further significant accumulations were expected tonight those
highlights were ended. Locations to the south and east near the
Palouse and down to the Camas Prairie are still susceptible to the
northwest to southeast trajectory of exit associated with this
disturbances so those advisories along with the winter storm
warning for the Idaho Central Panhandle Mountains have been
maintained with some slight modification to the accumulation
amounts and more wording to reference the very slick road
conditions when pavement temperatures dropped below freezing near
and shortly after sundown today. Additionally some fog was added
to the forecast earlier on, primarily as it appeared in proximity
to the more intense snow of this evening but right now it seems to
have gone and mostly low stratus has taken its place. /Pelatti
&&
.AVIATION...
06Z TAFS: Slow exit to the southeast of a weather disturbance
bringing mostly snow to majority of aviation areas allows for
primarily IFR ceilings to linger as most of the intense snowfall has
already occurred and/or moving out of the area to the southeast. Fog
has accompanied the snow at times. A weak frontal may very well
allow snow to intensify near the Palouse early Monday morning
ahead of yet another weather system coming up from the south which
will allow a good part of the time interval after 03Z Tuesday down
south to become wet as well with more rain/snow. /Pelatti
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 20 31 18 32 19 39 / 20 10 10 0 0 0
Coeur d`Alene 18 30 16 33 14 38 / 40 10 10 0 0 0
Pullman 27 33 25 39 25 42 / 80 50 40 20 10 10
Lewiston 33 40 29 43 29 47 / 90 40 50 20 10 10
Colville 16 32 16 37 12 40 / 20 10 10 0 0 0
Sandpoint 14 28 14 31 11 35 / 20 10 10 0 0 0
Kellogg 16 29 17 34 13 39 / 100 40 30 10 0 0
Moses Lake 27 38 26 41 23 43 / 20 10 20 10 10 0
Wenatchee 27 35 25 38 24 40 / 50 40 30 10 10 10
Omak 21 33 22 36 18 38 / 20 20 10 0 0 0
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Winter Weather Advisory until 10 AM PST Monday for Idaho Palouse.
Winter Storm Warning until 10 AM PST Monday for Central
Panhandle Mountains.
Winter Weather Advisory until 10 AM PST Monday for Lewis and
Southern Nez Perce Counties.
WA...Winter Weather Advisory until 4 AM PST Monday for East Slopes
Northern Cascades.
Winter Weather Advisory until 10 AM PST Monday for Washington
Palouse.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
300 AM CST MON FEB 24 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 300 AM CST MON FEB 24 2014
...CURRENTLY AS OF 09Z...
WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED RIDGING ALONG
THE U.S. WEST COAST NORTHWARD THROUGH ALASKA...WHILE TROUGHING
DOMINATED FROM THE NORTH POLE SOUTHWARD THROUGH MUCH OF CANADA AND
THE NORTHERN TIER OF THE U.S.. WITHIN THIS TROUGHING...THERE ARE 3
IMPORTANT SHORTWAVE TROUGHS OF NOTE FOR THE FORECAST...
1. OVER SOUTHERN SASKATCHEWAN INTO NORTHWEST MONTANA...EXPECTED
TO BRING THE SNOW LATE TODAY INTO TONIGHT. DPVA AND ISENTROPIC
LIFT AHEAD OF THIS SHORTWAVE HAS SUPPORTED LIGHT SNOW ACROSS MUCH
OF MONTANA SOUTHEAST INTO NEBRASKA.
2. ALONG THE NUNAVUT/NORTHWEST TERRITORIES BORDER IN CANADA...
EXPECTED TO BRING THE ARCTIC COLD SHOT TO THE AREA TUESDAY NIGHT.
IN ITS WAKE SURFACE TEMPERATURES RANGE FROM A BITTER 20 TO 30
BELOW ZERO.
3. RIGHT NEAR THE NORTH POLE...SPECIFICALLY 84 N / 130 W...EXPECTED
TO BRING THE ARCTIC AIR FOR THURSDAY INTO THE WEEKEND. IN ITS
WAKE... 925MB TEMPS RANGE FROM -28 TO -34C PER GFS ANALYSIS.
OVER THE FORECAST AREA...SKIES REMAIN CLEAR DUE TO PLENTY OF DRY AIR
AS SEEN ON THE 00Z MPX SOUNDING. SOME CIRRUS IS BEGINNING TO
ENCROACH FROM THE WEST...THOUGH. TEMPERATURES HAVE SLOWLY COOLED
THROUGH THE NIGHT RESULTING FROM A WESTERLY BREEZE...WITH READINGS
IN THE LOWER SINGLE DIGITS.
... FORECAST ...
MODELS ARE IN GOOD AGREEMENT MARCHING THE FIRST SHORTWAVE TROUGH
INTO THE EASTERN DAKOTAS BY 00Z...OVER THE FORECAST AREA BY 06Z AND
INTO LOWER MICHIGAN BY 12Z TUE. 275-280K ISENTROPIC LIFT PROGS
SUGGEST THAT TO GET THE SNOW OVER MONTANA AND NEBRASKA INTO THE
FORECAST AREA...WE HAVE TO WAIT FOR THE SHORTWAVE TROUGH TO ARRIVE.
THIS IS WHY MODELS SLOWED DOWN OVER THE PAST FEW DAYS OF BRINGING
SNOW TO THE AREA. THE BEST LIFT...ALBEIT WEAK...IS PROGGED OVER THE
SOUTHWESTERN HALF OF THE FORECAST AREA BETWEEN 01-06Z...THEN SHIFTS
TO FAR SOUTHWEST WI BETWEEN 06-09Z BEFORE EXITING. PRECIPITATION
CHANCES HAVE BEEN ADJUSTED TO FIT THE TIMING OF THE LIFT SIGNAL.
STILL DOES NOT LOOK LIKE THERE WILL BE MUCH SNOW GIVEN THE WEAK
NATURE OF THE LIFT...PRECIPITABLE WATER ONLY 0.1-0.2 OF AN
INCH...AND THE SNOW RUNNING INTO THE DRY AIRMASS CURRENTLY IN PLACE.
ANY LIFT TOO IS MOSTLY ABOVE THE DENDRITIC GROWTH ZONE. PREVIOUS
FORECAST AMOUNTS OF LESS THAN 1 INCH SEEM REASONABLE.
REGARDING TEMPERATURES. 925MB READINGS AT 18Z TODAY ARE SIMILAR TO
YESTERDAY AT 18Z...BETWEEN -13 AND -16C. ONLY DIFFERENCES BETWEEN
TODAY AND YESTERDAY IS MORE CLOUD COVER AND STARTING OFF COLDER...
WHICH SHOULD KEEP HIGHS A LITTLE COOLER. IN THE WAKE OF THE
SHORTWAVE TROUGH PASSAGE TONIGHT...925MB TEMPS COOL TO -14 TO -19C.
A NORTHWEST BREEZE COMBINED WITH CLOUDS SHOULD HELP TO HOLD LOWS UP
SOMEWHAT...BUT READINGS SHOULD FALL INTO THE SINGLE DIGITS ABOVE AND
BELOW ZERO THROUGH ADVECTION...COLDEST OVER THE NORTHWEST HALF OF
THE FORECAST AREA.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 300 AM CST MON FEB 24 2014
THE BIG IMPACT STORY HERE IS THE COLD...
SHORTWAVE TROUGH CURRENTLY OVER THE NUNAVUT/NORTHWEST TERRITORIES
REGION IS PROGGED TO DROP THROUGH THE FORECAST AREA LATE
TUESDAY...USHERING IN THE FIRST SURGE OF BITTER COLD ARCTIC AIR.
TROUGH SHOULD GO THROUGH PRECIP FREE WITH JUST SOME CLOUDS. 925MB
TEMPS PLUMMET TO -21 TO -24C BY 06Z WEDNESDAY...SENDING SURFACE
TEMPERATURES DOWN BELOW ZERO. WITH THE COLD AIR FIRMLY ENTRENCHED
FOR 06-12Z...TEMPERATURES SHOULD IN MOST LOCATIONS DIP INTO TEENS
BELOW ZERO. MOS GUIDANCE WIND FORECASTS SUGGEST THE TYPICAL COLD
SPOTS COULD DECOUPLE...THUS HAVE THEM APPROACHING 20 BELOW. A WIND
CHILL ADVISORY IS A GIVEN FOR TUESDAY NIGHT INTO WEDNESDAY MORNING.
A BRIEF BREAK IN THE COLD AIR COMES WEDNESDAY AFTERNOON AS WESTERLY
WINDS INCREASE AND PULL IN SOME DOWNSLOPED AIR OFF THE ROCKIES. THIS
INCREASE IS A RESULT OF THE NEXT SHORTWAVE TROUGH NEAR THE NORTH
POLE DROPPING INTO THE MN ARROWHEAD. 925MB WINDS APPROACH 45-50 KT
AT 00Z THURSDAY WEST OF THE MISSISSIPPI RIVER...BRINGING UP CONCERN
OF A POSSIBLE WIND ADVISORY. HOWEVER...A STRONG INVERSION LOOKS TO
DEVELOP TO PRECLUDE MIXING THOSE HIGHER WINDS DOWN. IT STILL WILL BE
BRISK...THOUGH...AND STRONG ENOUGH TO RESULT IN SOME BLOWING AND
DRIFTING OF SNOW IN OPEN AREAS.
NEXT ARCTIC COLD SHOT WHICH IS MUCH MORE IMPRESSIVE COMES IN LATE
WEDNESDAY NIGHT. THE AFOREMENTIONED NORTH POLE SHORTWAVE CROSSES
UPPER MICHIGAN WEDNESDAY NIGHT...DRAGGING AN ARCTIC COLD FRONT
THROUGH THE FORECAST AREA. A STRONG PRESSURE RISE IS PROGGED BEHIND
THIS FRONT WHICH SHOULD RESULT IN A PERIOD OF BRISK NORTHWEST WINDS.
THEN 925MB TEMPS PLUMMET TO -23 TO -27C AT 12Z THURSDAY. DID NOT GO
AS COLD AS THESE WOULD SUGGEST GIVEN THE LATE ARRIVAL OF THE COLD
AIR AND PLENTY OF WIND. STILL...THE WIND CHILLS ARE PLENTY LOW
ENOUGH FOR AN ADVISORY.
THURSDAY AND THURSDAY NIGHT LOOK DOWNRIGHT COLD. 850MB TEMP
ANOMALIES ARE PROGGED BETWEEN 2.5-3 STANDARD DEVIATIONS BELOW
NORMAL...SUGGESTING RECORD TERRITORY. IN ADDITION...HIGH PRESSURE
SETTLES OVERHEAD THURSDAY NIGHT...SETTING UP POTENTIAL FOR
TEMPERATURES TO TANK. ONLY CAVEAT WILL BE SOME INCREASING MID/HIGH
CLOUDS LATER THURSDAY NIGHT. SOME WISCONSIN COLD SPOTS COULD DIP TO
30 BELOW OR COLDER...AS INDICATED BY THE MEX GUIDANCE.
FOR FRIDAY THROUGH MONDAY...THE FORECAST AREA WILL BE IN-BETWEEN
ARCTIC COLD UPPER TROUGHING ENCOMPASSING MUCH OF SOUTHERN CANADA AND
SHORTWAVE TROUGHS TRAVERSING THE SOUTHERN 2/3 OF THE U.S.. AT THE
SAME TIME AT THE SURFACE...ARCTIC HIGH PRESSURE SHOULD BE IN PLACE
FOR MUCH OF THE TIME. ONE SHORTWAVE MAY BRING SOME LIGHT SNOW TO
LOCATIONS SOUTH OF I-90 ON FRIDAY...IF IT CAN MAKE IT THROUGH THE
DRY AIR. ONLY KEPT 20 PERCENT CHANCES IN FOR THIS TIME PERIOD. SAME
HOLDS TRUE FOR ANOTHER SHORTWAVE TROUGH GOING BY SATURDAY NIGHT INTO
SUNDAY...THOUGH THE TRACK IS A BIT FARTHER NORTH SO CHANCES ARE A
LITTLE HIGHER. TEMPERATURES WILL STAY WELL BELOW NORMAL BEING UNDER
THE INFLUENCE OF THE ARCTIC SURFACE HIGH...THOUGH SOME GRADUAL
MODERATION SHOULD TAKE PLACE AS THE EARLY MARCH SUN WORKS ON THE
AIR. MORE WIND CHILL ADVISORIES ARE LIKELY...THOUGH...ESPECIALLY
FRIDAY NIGHT INTO SATURDAY MORNING.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1130 PM CST SUN FEB 23 2014
VFR CONDITIONS TO CONTINUE THROUGH MONDAY AS HIGH PRESSURE SINKS
SLOWLY INTO MONTANA WHILE KEEPING THE RIDGE EXTENDING FROM THE
HIGH OVER IOWA INTO ILLINOIS. A SHORT WAVE TROUGH APPROACHING FROM
THE NORTHWEST WILL START TO SPREAD HIGH AND MID LEVEL CLOUDS OVER
THE AREA THROUGH THE AFTERNOON WITH GRADUALLY LOWER CEILINGS. THE
FORCING FROM THE WAVE WILL START TO MOVE IN MONDAY EVENING AND THE
CONCERN BECOMES WHETHER THE FORCING WILL BE STRONG ENOUGH TO
PRODUCE SATURATION OR NOT. THE 24.00Z NAM SUGGEST THE BEST
ISENTROPIC UP GLIDE ON THE 275K SURFACE WILL STAY SOUTH OF THE
AREA WITH AROUND 30 MB NEEDED TO OBTAIN SATURATION. IF THIS
OCCURS...WOULD NOT EXPECT MUCH MORE THAN FLURRIES TO OCCUR. THE
24.00Z GFS ALSO SHOWS THE BEST ISENTROPIC UP GLIDE STAYING SOUTH
BUT IS STRONGER THAN THE NAM FOR WHAT IT DOES BRING ACROSS THE
AREA...BETWEEN 2 AND 3 UBAR/S. THE GFS DOES SATURATE AND WOULD
BRING LIGHT SNOW INTO KRST DURING THE EVENING AND TO KLSE AFTER
25.06Z. THE 23.21Z SREF WOULD SUGGEST THE BEST VISIBILITY REDUCING
SNOW WILL STAY SOUTH WITH THE BETTER FORCING...BUT DOES SHOW
PRETTY DECENT PROBABILITIES OF A VISIBILITY OF 3 MILES OR LESS AT
KRST. HAVE THUS BROUGHT IN MVFR CONDITIONS WITH LIGHT SNOW TO KRST
FOR MONDAY EVENING.
&&
.CLIMATE...
ISSUED AT 300 AM CST MON FEB 24 2014
GIVEN ALL THE COLD AIR TO ROUND OUT THE MONTH OF FEBRUARY...HERE IS
HOW FEBRUARY AND THE WINTER OVERALL WOULD STACK UP COMPARED TO
RECORDS BASED ON THE CURRENT FORECAST...
...FOR THE MONTH OF FEBRUARY...
LA CROSSE... 9.3 AVERAGE TEMPERATURE...3RD COLDEST
COLDER FEBRUARYS...
1873... 3.9
1936... 4.3
ROCHESTER... 6.7 AVERAGE TEMPERATURE...4TH COLDEST
COLDER FEBRUARYS...
1936... 0.5
1979... 5.7
1917... 6.0
...FOR THE WINTER...DECEMBER THROUGH FEBRUARY...
LA CROSSE... 11.5 AVERAGE TEMPERATURE...5TH COLDEST
COLDER WINTERS...
1872-1873... 8.4
1874-1875... 10.5
1977-1978... 11.4
1935-1936... 11.4
ROCHESTER... 8.8 AVERAGE TEMPERATURE...5TH COLDEST
COLDER WINTERS...
1978-1979... 5.6
1886-1887... 5.9
1935-1936... 8.1
1977-1978... 8.7
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...04
CLIMATE...AJ/RRS
AREA FORECAST DISCUSSION
NWS TAUNTON MA
1018 AM EST MON FEB 24 2014
.SYNOPSIS...
A STRONG COLD FRONT WAS EXITING THE REGION EARLY THIS MORNING...
BRINGING PROGRESSIVELY COLDER CONDITIONS THROUGH NEXT WEEKEND.
MAINLY DRY CONDITIONS WILL BE IN PLACE AS LARGE HIGH PRESSURE
MOVES ACROSS. ONE EXCEPTION WILL BE FOR THE RISK OF ACCUMULATING
SNOWFALL FOR WEDNESDAY AS LOW PRESSURE DEVELOPS WELL SOUTH OF NEW
ENGLAND. ANOTHER LOW MAY BRING SOME SNOWFALL NEXT WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
1015 AM UPDATE...
POST FRONTAL STRATO-CU FILLING BACK IN ACROSS THE INTERIOR AS LOW
AND MID LEVEL MOISTURE FROM THE N SPILLS INTO THE REGION AND
EXPECT SCT-BKN CU TO DEVELOP IN THE COASTAL PLAIN. STEEP LOW
LEVEL LAPSE RATES AND LOW LEVEL MOISTURE SUPPORT A FEW FLURRIES
OR SNOW SHOWERS...ESPECIALLY N OF THE PIKE WHERE HRRR IS
TARGETING. STRONG COLD AIR ADVECTION WILL RESULT IN TEMPS
REMAINING NEARLY STEADY OR PERHAPS FALLING A FEW DEGREES ALONG
WITH GUSTY W/NW WINDS.
PREVIOUS DISCUSSION...
OTHERWISE TODAY...AFTER THE FRONT/PRECIP BAND SHIFTS
OFFSHORE...STRONG COLD ADVECTION WILL DEFINE THE WX. H85
TEMPERATURES WILL BE DECLINING FROM AN AVERAGE OF ABOUT -5C TO
ABOUT -16C BY THE OVERNIGHT HOURS TONIGHT. DRY AIR WILL ALSO BE
RAPIDLY MOVING IN WITH TIME AS WELL. THEREFORE...EXPECT HIGH TEMPS
TO OCCUR BY LATE THIS MORNING WITH COOLING EXPECTED THROUGH THE
AFTERNOON HOURS...WITH RANGES FROM THE LOW TO UPPER 30S. THE
COMBINATION OF STRONG CYCLONIC CURVATURE ALOFT WITH A SHORTWAVE
MOVING ACROSS THE AREA...STEEP SFC-H9 LAPSE RATES ON THE ORDER OF
8C/KM AND A BIT OF TRAPPED MID LVL MOISTURE BENEATH A BUILDING
SUBSIDENCE INVERSION WILL LIKELY YIELD WIDESPREAD CU-STRATOCU
ACROSS THE AREA DURING PEAK HEATING. THE DEEP NEAR SFC UNSTABLE
LAYER MAY ALSO BE ENOUGH TO INDUCE SOME LOCALIZED FLURRY ACTIVITY
ESPECIALLY IN THE W WHERE CAA WILL BE MAXIMIZED. HAVE ADDED SOME
SLIGHT CHANCE POPS TO THE FORECAST ALONG WITH THE INCREASING
CLOUDS. OCEAN EFFECT CLOUDS ARE ALSO POSSIBLE ACROSS PORTIONS OF
CAPE COD GIVEN THE WIND TRAJECTORY AND OCEAN BL INSTABILITY.
ALSO...WITH THIS DEEP LAYER MIXING...MUCH OF THE MOMENTUM IN A
NEARLY 40 KT LLJ SHOULD BE TAPPED. THEREFORE...EXPECT BRISK NW
WINDS GUSTING 30-35 MPH AT TIMES THROUGH THE DAY. THIS WILL MAKE
FOR WIND CHILL VALUES IN THE 20S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
TONIGHT...
NOT TOO MUCH CHANGE FROM THE DAY AS CYCLONIC CURVATURE...DECENT
SFC PRES GRADIENT AND TRAPPED MID LVL MOISTURE REMAIN IN PLAY
ACROSS THE AREA. THEREFORE..EXPECT AT LEAST SOME CLOUDS AND WINDS
TO REMAIN THROUGH THE OVERNIGHT HOURS. WHILE THIS WILL LIMIT THE
ABILITY TO RADIATE...NORMAL DIURNAL TRENDS SHOULD STILL ALLOW MINS
INTO THE LOW TEENS AND 20S. WITH WINDS OF AROUND 10 MPH STILL
POSSIBLE...THIS WOULD YIELD SOME WIND CHILLS BELOW ZERO FOR
PORTIONS OF THE INTERIOR AND IN THE SINGLE DIGITS CLOSER TO THE
SHORELINES.
TUESDAY...
A COLD AND BRISK START IS EXPECTED AS WINDS CONTINUE TO GUST UP TO
ABOUT 20 MPH AFTER SUNRISE AND MIXING SETS UP. ANOTHER ROUND OF
PARTLY CLOUDY CONDITIONS AND HIGHER SUN ANGLES SHOULD ALLOW HIGHS
TO INCREASE INTO THE MID 20S TO LOW 30S DESPITE THIS COOLER START
BUT WITH WIND CHILL VALUES IN THE TEENS TO LOW 20S. MAINLY DRIER
WX AS NOSE OF HIGH PRES BEGINS TO BUILD OVER FROM THE
SW...LIMITING THE POTENTIAL FOR MORE FLURRY ACTIVITY IN COMPARISON
TO MON.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
HIGHLIGHTS...
* JANUARY-LIKE TEMPERATURES THIS WEEK AND AS WE ENTER MARCH NEXT
WEEKEND
* RISK FOR ACCUMULATING SNOW WED AND AGAIN NEXT WEEKEND
* OTHERWISE MAINLY DRY CONDITIONS PREVAIL
SYNOPTIC OVERVIEW...
NOT MUCH CHANGE IN THE FORECAST FROM PREVIOUS DAYS. HIGH AMPLITUDE
NORTHERN STREAM PATTERN DEVELOPS WITH POLAR VORTEX BEING DISPLACED
SOUTHWARD INTO ONTARIO BY THU. THIS RESULTS IN A STEADY STREAM OF
ARCTIC AIR INTO SOUTHERN NEW ENGLAND THIS WEEK AND INTO NEXT
WEEKEND. THAT/S THE EASY PART OF THE FORECAST. WHAT BECOMES
DIFFICULT TO NAIL DOWN AT THIS TIME RANGE IS THE INTENSITY AND TRACK
OF ANY EAST CYCLOGENESIS...AS ARCTIC SHORT WAVES PIVOT AROUND THE
SOUTHERN BASE OF THE POLAR VORTEX. FURTHER COMPLICATING THE FORECAST
IS IF PACIFIC ENERGY UNDERCUTTING THE WESTERN RIDGE INTERACTS
/PHASING VS UNPHASED/ WITH ARCTIC SHORT WAVE TROUGHS ALONG THE EAST
COAST.
MODEL PREFERENCES AND SENSIBLE WEATHER...
WEDNESDAY...00Z DETERMINISTIC GFS AND ECMWF IN AGREEMENT ON AN
UNPHASED SOLUTION WITH NORTHERN STREAM LOW MOVING ACROSS SOUTHEAST
CANADA AND EAST COAST CYCLOGENESIS TRACKING WELL SOUTHEAST OF
40N/70W BENCHMARK. HOWEVER APPEARS THERE WILL BE ENOUGH MID LEVEL
LIFT TO INDUCE AN INVERTED SURFACE TROUGH BETWEEN THESE TWO LOWS TO
GENERATE A FEW TENTHS OF QPF OVER SOUTHERN NEW ENGLAND. THUS A LOW
TO MODERATE RISK OF A FEW FLUFFY INCHES OF SNOW...WITH HIGHEST RISK
OVER SOUTHEAST MA.
HOWEVER CAN/T COMPLETELY RULE OUT A STRONGER/PHASED SOLUTION AS
ARCTIC SHORT WAVE/PV ANOMALY THAT INDUCES EAST COAST CYCLOGENESIS
IS CURRENTLY MOVING ACROSS NORTHWEST CANADA EARLY THIS MORNING.
MODELS LIKELY NOT SAMPLING THIS PACKET OF JET ENERGY VERY WELL
GIVEN THIS IS A DATA SPARSE AREA. THUS WILL HAVE TO WAIT UNTIL
THIS FEATURE ENTERS SOUTHERN CANADA BEFORE MODELS BEGIN BETTER
SAMPLING OF THIS JET ENERGY. IF THIS SHORT WAVE TROUGH IS MORE
AMPLIFIED THAN MODELS CURRENTLY SIMULATE...A TRACK CLOSER TO THE
COAST IS PLAUSIBLE. THEREFORE ITS STILL TOO EARLY TO LOCK INTO A
SINGLE SCENARIO. HOWEVER FOR THE MOMENT WILL PLAY THE MOST LIKELY
SCENARIO...A LOW TO MODERATE RISK OF A FEW INCHES OF FLUFFY SNOW.
THURSDAY THRU SUNDAY...ANOTHER ARCTIC FRONT MOVES ACROSS THE AREA
THU OR FRI WITH GEFS AND ECENS ENSEMBLE POST FRONTAL 850 MEAN TEMPS
VARYING FROM -15C TO -20C ACROSS SOUTHERN NEW ENGLAND. THUS COLDER
THAN NORMAL TEMPS HOWEVER ANY RECORD BREAKING COLD SHOULD REMAIN
WEST OF NEW ENGLAND ACROSS THE GREAT LAKES GIVEN PROXIMITY OF COLD
AIR CORE. WILL ALSO HAVE TO WATCH FOR POTENTIAL SNOW SQUALLS ALONG
AND AHEAD OF FRONTAL BOUNDARY...AS INCREASING SUN ANGLE /SAT MAR
1ST/ AND COLD AIR ALOFT WILL YIELD STEEP LOW LEVEL LAPSE RATES.
THEN NEXT WEEKEND THE FOCUS WILL BE ON PACIFIC ENERGY MARCHING
ACROSS THE SOUTHERN STATES AND ITS POSSIBLE INTERACTION/PHASING WITH
THE NORTHERN STREAM OVER THE NORTHEAST. THE 00Z GEFS AND ECENS
ENSEMBLE MEAN ARE WELL OFFSHORE WITH ANY CYCLOGENESIS...AS WELL AS
THE 00Z GFS. THE 00Z ECMWF IS MUCH CLOSER TO THE COAST BUT ALSO
WEAKER. GIVEN THE UNCERTAINTY WILL CONTINUE WITH CHANCE POPS FOR
NEXT WEEKEND.
&&
.AVIATION /15Z MONDAY THROUGH FRIDAY/...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH TUESDAY/...
7 AM UPDATE...
NO MAJOR CHANGES FROM PREVIOUS 06Z TAFS.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
TODAY AND TUESDAY...HIGH CONFIDENCE. MAINLY VFR THROUGH THE
PERIOD...BUT SOME LOW CU BETWEEN 030-060 POSSIBLE THROUGH DAYLIGHT
HOURS ALONG WITH SOME LIGHT SNOW SHOWERS POSSIBLE MAINLY W OF A
IJD-ORH-EEN LINE TODAY. NW WINDS GUSTING 25-30 KT AT TIMES
TODAY...W WINDS GUST 20-25 KT ON TUE.
KBOS TERMINAL...HIGH CONFIDENCE IN TAF.
KBDL TERMINAL...HIGH CONFIDENCE IN TAF.
OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...
VFR ALONG WITH GUSTY WNW WINDS. THE EXCEPTION WILL BE WED WHEN WINDS
WILL BRIEFLY RELAX. HOWEVER A PERIOD OF SNOW IS POSSIBLE WED WITH
MVFR CONDITIONS. HIGHEST PROBABILITY OF SNOW AND MVFR CONDITIONS IS
ACROSS SOUTHEAST MA WED.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
THROUGH TUESDAY...HIGH CONFIDENCE.
W-NW WINDS WILL BE INCREASING THROUGH THE DAY TODAY WITH GUSTS
WIDESPREAD 25-30 KT EXPECTED. A FEW GUSTS MAY APPROACH GALE
FORCE...BUT THE MAJORITY SHOULD REMAIN BELOW. THESE WINDS WILL
MAINTAIN THROUGH THE OVERNIGHT HOURS TONIGHT...ONLY DIMINISHING
INTO THE MORNING HOURS FOR TUE THEN DROPPING BELOW SMALL CRAFT
THRESHOLDS BY THE LATE DAY TUE.
WITH INCREASING WINDS EXPECT SEAS TO BUILD AS WELL...REACHING
5-7FT AT TIMES MAINLY ON THE OCEAN WATERS.
OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...
GUSTY WNW WINDS AND PERIODS OF FREEZING SPRAY ARE EXPECTED AS ARCTIC
AIR OVERSPREADS THE REGION. WINDS BRIEFLY RELAX WED AS ONE AREA OF
LOW PRES TRACKS ACROSS SOUTHEAST CANADA AND A POTENTIAL GALE CENTER
PASSES SOUTHEAST OF 40N/70W BENCHMARK. A PERIOD OF SNOW WITH REDUCED
VSBY IS LIKELY WED ESPECIALLY OVER THE WATERS SOUTHEAST OF
NANTUCKET.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 1 PM EST TUESDAY FOR ANZ230>237-251.
SMALL CRAFT ADVISORY UNTIL 7 PM EST TUESDAY FOR ANZ250-254>256.
&&
$$
SYNOPSIS...NOCERA/DOODY
NEAR TERM...KJC/DOODY
SHORT TERM...DOODY
LONG TERM...NOCERA
AVIATION...NOCERA/DOODY
MARINE...NOCERA/DOODY
AREA FORECAST DISCUSSION
NWS TAUNTON MA
713 AM EST MON FEB 24 2014
.SYNOPSIS...
A STRONG COLD FRONT WAS EXITING THE REGION EARLY THIS MORNING...
BRINGING PROGRESSIVELY COLDER CONDITIONS THROUGH NEXT WEEKEND.
MAINLY DRY CONDITIONS WILL BE IN PLACE AS LARGE HIGH PRESSURE
MOVES ACROSS. ONE EXCEPTION WILL BE FOR THE RISK OF ACCUMULATING
SNOWFALL FOR WEDNESDAY AS LOW PRESSURE DEVELOPS WELL SOUTH OF NEW
ENGLAND. ANOTHER LOW MAY BRING SOME SNOWFALL NEXT WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
7 AM UPDATE...
COLD FRONT NOW OVER NANTUCKET WILL MOVE OFFSHORE SHORTLY. STRONG
COLD AIR ADVECTION BEHIND THE FRONT WITH SURFACE DEW PTS ALREADY
FALLING INTO THE SINGLE DIGITS ACROSS NORTHEAST MA. CLOUD SHIELD
OVER SOUTHEAST MA ASSOCIATED WITH THE FRONT WILL MOVE OFFSHORE
LATER THIS MORNING. HOWEVER POST FRONTAL CLOUDS WILL FILL BACK IN
AS COLD AIR ALOFT COMBINES WITH DIURNAL HEATING TO YIELD STEEP LOW
LEVEL LAPSE RATES. THIS COUPLED WITH CYCLONIC FLOW ALOFT MAY YIELD
SCT SNOW SHOWERS THIS AFTERNOON...ESPECIALLY OVER THE HIGHER
TERRAIN WHERE UPSLOPE FLOW WILL PROVIDE ADDITIONAL LIFT. HOWEVER DRY
LOW LEVELS MAY ONLY YIELD SOME FLURRIES OR VIRGA. PREVIOUS
FORECAST CAPTURES THESE DETAILS NICELY...THUS NO MAJOR CHANGES
WITH THIS FORECAST UPDATE. EARLIER DISCUSSION BELOW.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
A COMBINATION OF BOTH OBS AND MSAS SUGGEST SFC COLD FRONT HAS
MOVED OFFSHORE OF ALL SRN NEW ENGLAND COASTLINES SAVE FOR THE
CAPE/ISLANDS AS OF 0830Z. NOW IN CLOSE ASSOCIATION WITH THIS FRONT
IS A BAND OF WSR-88D ECHOS OF 25-30 DBZ WHICH ALSO CONTINUE TO
GRADUALLY SLIDE OFF THE S COAST AND SHOULD BE OFFSHORE OF
EVERYWHERE BY 10-12Z BASED ON CURRENT SPEED AND TIMING. DESPITE
THE ECHOS...PRECIP HAS REALLY STRUGGLED TO REACH THE SFC THANKS TO
10-15F DWPT DEPRESSIONS ACROSS THE REGION. EVEN THEN...WITH SFC
TEMPS ABOVE FREEZING AND A LACK OF HEAVY PRECIP TO FORCE THE NEAR
SFC LAYER TO WET-BULB...ANY PRECIP THAT HAS REACHED THE SFC HAS
BEEN IN THE FORM OF LIGHT RAIN. BASED EARLY MORNING POPS ON THE
LATEST RAP WHICH CONTINUES TO FOLLOW THIS BAND WELL BUT CAPPED ANY
POPS AT CHANCE.
OTHERWISE TODAY...AFTER THE FRONT/PRECIP BAND SHIFTS
OFFSHORE...STRONG COLD ADVECTION WILL DEFINE THE WX. H85
TEMPERATURES WILL BE DECLINING FROM AN AVERAGE OF ABOUT -5C TO
ABOUT -16C BY THE OVERNIGHT HOURS TONIGHT. DRY AIR WILL ALSO BE
RAPIDLY MOVING IN WITH TIME AS WELL. THEREFORE...EXPECT HIGH TEMPS
TO OCCUR BY LATE THIS MORNING WITH COOLING EXPECTED THROUGH THE
AFTERNOON HOURS...WITH RANGES FROM THE LOW TO UPPER 30S. THE
COMBINATION OF STRONG CYCLONIC CURVATURE ALOFT WITH A SHORTWAVE
MOVING ACROSS THE AREA...STEEP SFC-H9 LAPSE RATES ON THE ORDER OF
8C/KM AND A BIT OF TRAPPED MID LVL MOISTURE BENEATH A BUILDING
SUBSIDENCE INVERSION WILL LIKELY YIELD WIDESPREAD CU-STRATOCU
ACROSS THE AREA DURING PEAK HEATING. THE DEEP NEAR SFC UNSTABLE
LAYER MAY ALSO BE ENOUGH TO INDUCE SOME LOCALIZED FLURRY ACTIVITY
ESPECIALLY IN THE W WHERE CAA WILL BE MAXIMIZED. HAVE ADDED SOME
SLIGHT CHANCE POPS TO THE FORECAST ALONG WITH THE INCREASING
CLOUDS. OCEAN EFFECT CLOUDS ARE ALSO POSSIBLE ACROSS PORTIONS OF
CAPE COD GIVEN THE WIND TRAJECTORY AND OCEAN BL INSTABILITY.
ALSO...WITH THIS DEEP LAYER MIXING...MUCH OF THE MOMENTUM IN A
NEARLY 40 KT LLJ SHOULD BE TAPPED. THEREFORE...EXPECT BRISK NW
WINDS GUSTING 30-35 MPH AT TIMES THROUGH THE DAY. THIS WILL MAKE
FOR WIND CHILL VALUES IN THE 20S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
TONIGHT...
NOT TOO MUCH CHANGE FROM THE DAY AS CYCLONIC CURVATURE...DECENT
SFC PRES GRADIENT AND TRAPPED MID LVL MOISTURE REMAIN IN PLAY
ACROSS THE AREA. THEREFORE..EXPECT AT LEAST SOME CLOUDS AND WINDS
TO REMAIN THROUGH THE OVERNIGHT HOURS. WHILE THIS WILL LIMIT THE
ABILITY TO RADIATE...NORMAL DIURNAL TRENDS SHOULD STILL ALLOW MINS
INTO THE LOW TEENS AND 20S. WITH WINDS OF AROUND 10 MPH STILL
POSSIBLE...THIS WOULD YIELD SOME WIND CHILLS BELOW ZERO FOR
PORTIONS OF THE INTERIOR AND IN THE SINGLE DIGITS CLOSER TO THE
SHORELINES.
TUESDAY...
A COLD AND BRISK START IS EXPECTED AS WINDS CONTINUE TO GUST UP TO
ABOUT 20 MPH AFTER SUNRISE AND MIXING SETS UP. ANOTHER ROUND OF
PARTLY CLOUDY CONDITIONS AND HIGHER SUN ANGLES SHOULD ALLOW HIGHS
TO INCREASE INTO THE MID 20S TO LOW 30S DESPITE THIS COOLER START
BUT WITH WIND CHILL VALUES IN THE TEENS TO LOW 20S. MAINLY DRIER
WX AS NOSE OF HIGH PRES BEGINS TO BUILD OVER FROM THE
SW...LIMITING THE POTENTIAL FOR MORE FLURRY ACTIVITY IN COMPARISON
TO MON.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
HIGHLIGHTS...
* JANUARY-LIKE TEMPERATURES THIS WEEK AND AS WE ENTER MARCH NEXT
WEEKEND
* RISK FOR ACCUMULATING SNOW WED AND AGAIN NEXT WEEKEND
* OTHERWISE MAINLY DRY CONDITIONS PREVAIL
SYNOPTIC OVERVIEW...
NOT MUCH CHANGE IN THE FORECAST FROM PREVIOUS DAYS. HIGH AMPLITUDE
NORTHERN STREAM PATTERN DEVELOPS WITH POLAR VORTEX BEING DISPLACED
SOUTHWARD INTO ONTARIO BY THU. THIS RESULTS IN A STEADY STREAM OF
ARCTIC AIR INTO SOUTHERN NEW ENGLAND THIS WEEK AND INTO NEXT
WEEKEND. THAT/S THE EASY PART OF THE FORECAST. WHAT BECOMES
DIFFICULT TO NAIL DOWN AT THIS TIME RANGE IS THE INTENSITY AND TRACK
OF ANY EAST CYCLOGENESIS...AS ARCTIC SHORT WAVES PIVOT AROUND THE
SOUTHERN BASE OF THE POLAR VORTEX. FURTHER COMPLICATING THE FORECAST
IS IF PACIFIC ENERGY UNDERCUTTING THE WESTERN RIDGE INTERACTS
/PHASING VS UNPHASED/ WITH ARCTIC SHORT WAVE TROUGHS ALONG THE EAST
COAST.
MODEL PREFERENCES AND SENSIBLE WEATHER...
WEDNESDAY...00Z DETERMINISTIC GFS AND ECMWF IN AGREEMENT ON AN
UNPHASED SOLUTION WITH NORTHERN STREAM LOW MOVING ACROSS SOUTHEAST
CANADA AND EAST COAST CYCLOGENESIS TRACKING WELL SOUTHEAST OF
40N/70W BENCHMARK. HOWEVER APPEARS THERE WILL BE ENOUGH MID LEVEL
LIFT TO INDUCE AN INVERTED SURFACE TROUGH BETWEEN THESE TWO LOWS TO
GENERATE A FEW TENTHS OF QPF OVER SOUTHERN NEW ENGLAND. THUS A LOW
TO MODERATE RISK OF A FEW FLUFFY INCHES OF SNOW...WITH HIGHEST RISK
OVER SOUTHEAST MA.
HOWEVER CAN/T COMPLETELY RULE OUT A STRONGER/PHASED SOLUTION AS
ARCTIC SHORT WAVE/PV ANOMALY THAT INDUCES EAST COAST CYCLOGENESIS
IS CURRENTLY MOVING ACROSS NORTHWEST CANADA EARLY THIS MORNING.
MODELS LIKELY NOT SAMPLING THIS PACKET OF JET ENERGY VERY WELL
GIVEN THIS IS A DATA SPARSE AREA. THUS WILL HAVE TO WAIT UNTIL
THIS FEATURE ENTERS SOUTHERN CANADA BEFORE MODELS BEGIN BETTER
SAMPLING OF THIS JET ENERGY. IF THIS SHORT WAVE TROUGH IS MORE
AMPLIFIED THAN MODELS CURRENTLY SIMULATE...A TRACK CLOSER TO THE
COAST IS PLAUSIBLE. THEREFORE ITS STILL TOO EARLY TO LOCK INTO A
SINGLE SCENARIO. HOWEVER FOR THE MOMENT WILL PLAY THE MOST LIKELY
SCENARIO...A LOW TO MODERATE RISK OF A FEW INCHES OF FLUFFY SNOW.
THURSDAY THRU SUNDAY...ANOTHER ARCTIC FRONT MOVES ACROSS THE AREA
THU OR FRI WITH GEFS AND ECENS ENSEMBLE POST FRONTAL 850 MEAN TEMPS
VARYING FROM -15C TO -20C ACROSS SOUTHERN NEW ENGLAND. THUS COLDER
THAN NORMAL TEMPS HOWEVER ANY RECORD BREAKING COLD SHOULD REMAIN
WEST OF NEW ENGLAND ACROSS THE GREAT LAKES GIVEN PROXIMITY OF COLD
AIR CORE. WILL ALSO HAVE TO WATCH FOR POTENTIAL SNOW SQUALLS ALONG
AND AHEAD OF FRONTAL BOUNDARY...AS INCREASING SUN ANGLE /SAT MAR
1ST/ AND COLD AIR ALOFT WILL YIELD STEEP LOW LEVEL LAPSE RATES.
THEN NEXT WEEKEND THE FOCUS WILL BE ON PACIFIC ENERGY MARCHING
ACROSS THE SOUTHERN STATES AND ITS POSSIBLE INTERACTION/PHASING WITH
THE NORTHERN STREAM OVER THE NORTHEAST. THE 00Z GEFS AND ECENS
ENSEMBLE MEAN ARE WELL OFFSHORE WITH ANY CYCLOGENESIS...AS WELL AS
THE 00Z GFS. THE 00Z ECMWF IS MUCH CLOSER TO THE COAST BUT ALSO
WEAKER. GIVEN THE UNCERTAINTY WILL CONTINUE WITH CHANCE POPS FOR
NEXT WEEKEND.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH TUESDAY/...
7 AM UPDATE...
NO MAJOR CHANGES FROM PREVIOUS 06Z TAFS.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
TODAY AND TUESDAY...HIGH CONFIDENCE. MAINLY VFR THROUGH THE
PERIOD...BUT SOME LOW CU BETWEEN 030-060 POSSIBLE THROUGH DAYLIGHT
HOURS ALONG WITH SOME LIGHT SNOW SHOWERS POSSIBLE MAINLY W OF A
IJD-ORH-EEN LINE TODAY. NW WINDS GUSTING 25-30 KT AT TIMES
TODAY...W WINDS GUST 20-25 KT ON TUE.
KBOS TERMINAL...HIGH CONFIDENCE IN TAF.
KBDL TERMINAL...HIGH CONFIDENCE IN TAF.
OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...
VFR ALONG WITH GUSTY WNW WINDS. THE EXCEPTION WILL BE WED WHEN WINDS
WILL BRIEFLY RELAX. HOWEVER A PERIOD OF SNOW IS POSSIBLE WED WITH
MVFR CONDITIONS. HIGHEST PROBABILITY OF SNOW AND MVFR CONDITIONS IS
ACROSS SOUTHEAST MA WED.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
THROUGH TUESDAY...HIGH CONFIDENCE.
W-NW WINDS WILL BE INCREASING THROUGH THE DAY TODAY WITH GUSTS
WIDESPREAD 25-30 KT EXPECTED. A FEW GUSTS MAY APPROACH GALE
FORCE...BUT THE MAJORITY SHOULD REMAIN BELOW. THESE WINDS WILL
MAINTAIN THROUGH THE OVERNIGHT HOURS TONIGHT...ONLY DIMINISHING
INTO THE MORNING HOURS FOR TUE THEN DROPPING BELOW SMALL CRAFT
THRESHOLDS BY THE LATE DAY TUE.
WITH INCREASING WINDS EXPECT SEAS TO BUILD AS WELL...REACHING
5-7FT AT TIMES MAINLY ON THE OCEAN WATERS.
OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...
GUSTY WNW WINDS AND PERIODS OF FREEZING SPRAY ARE EXPECTED AS ARCTIC
AIR OVERSPREADS THE REGION. WINDS BRIEFLY RELAX WED AS ONE AREA OF
LOW PRES TRACKS ACROSS SOUTHEAST CANADA AND A POTENTIAL GALE CENTER
PASSES SOUTHEAST OF 40N/70W BENCHMARK. A PERIOD OF SNOW WITH REDUCED
VSBY IS LIKELY WED ESPECIALLY OVER THE WATERS SOUTHEAST OF
NANTUCKET.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 1 PM EST TUESDAY FOR ANZ230>237-251.
SMALL CRAFT ADVISORY UNTIL 7 PM EST TUESDAY FOR ANZ250-254>256.
&&
$$
SYNOPSIS...NOCERA/DOODY
NEAR TERM...NOCERA/DOODY
SHORT TERM...DOODY
LONG TERM...NOCERA
AVIATION...NOCERA/DOODY
MARINE...NOCERA/DOODY
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
532 AM CST MON FEB 24 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 350 AM CST MON FEB 24 2014
1038 MB ARCTIC HIGH PRESSURE ACROSS SRN ALBERTA AND SRN
SASKATCHEWAN WILL MOVE INTO SOUTH DAKOTA BY 12Z TUESDAY MORNING.
AN ARCTIC FRONT ACROSS NRN MT IS EXPECTED TO MOVE INTO THE FCST
AREA BY LATE AFTN AND BE THROUGH THE FCST AREA AND ACROSS KS BY
TUESDAY MORNING. LOWS IN THE SINGLE DIGITS ARE EXPECTED TONIGHT
WITH WIND CHILL READINGS AROUND 10 BELOW TO PERHAPS 15 BELOW ZERO
ACROSS NORTHERN NEB.
THE MODEL CONSENSUS SUGGESTS A PERIOD OF LIGHT SNOW
DEVELOPING...MAINLY ACROSS WRN NEBRASKA...AS THE FRONT MOVES
THROUGH. SNOWFALL AMOUNTS SHOULD BE LESS THAN AN INCH AND MAINLY
A DUSTING.
THERE IS QUITE A VARIETY OF MAX TEMPERATURE FORECASTS TO CHOOSE
FROM TODAY. THE FORECAST FOLLOWS A BLEND OF NAM...GEM REG...ECM
AND MET PLUS BIAS CORRECTION FOR HIGHS IN THE UPPER 20S NORTH TO
UPPER 30S SOUTH. THE NAM IS ACTUALLY FORECASTING MID 40S AT NORTH
PLATTE WHILE THE RAP SHOWS UPPER 20S AND THE ECM MID 30S. THIS IS
A FUNCTION OF THE SKY COVER INDICATED IN THE MODELS AND SOME
SOLNS SHOW A PERIOD OF CLEARING AHEAD OF THE ARCTIC FRONT. THE
MODEL CONSENSUS SUGGESTS CLEARING ACROSS WRN/SWRN
NEB...KAIA-KOGA-KIML AS A RESULT OF SOME SOUTHWEST WINDS
DEVELOPING. EAST OF THAT AREA IT LOOKS LIKE ARCTIC DRAPE SHOULD
CONTINUE WITH SOUTH WINDS.
THE LIGHT TO MODERATE SNOW ON RADAR EARLY THIS MORNING ACROSS
NCNTL NEB IS MOVING RAPIDLY EAST AND SHOULD BE REPLACED BY A
SECOND AREA OF SNOW LATER THIS MORNING A BIT FARTHER NORTH AND
EAST. THIS SNOW IS CURRENTLY SHOWING ON THE KUNR RADAR ACROSS WRN
SD. THE MODELS GENERATE A THIRD AREA OF SNOW THIS AFTERNOON BUT
THIS SHOULD PASS MOSTLY NORTH AND EAST OF THE FORECAST AREA. THIS
AREA OF SNOW IS CURRENTLY ACROSS SERN MT.
BEST SNOWFALL IS EXPECTED ACROSS BOYD COUNTY WITH QPF RANGES FROM
LESS THAN 0.10 INCHES IN THE UKMET...GEF AND GFS TO 0.30 INCHES
IN THE NMM WEST. THIS IS A WIDE RANGE AND THE CONSENSUS IS AROUND
0.15 INCHES. A 15 TO 20 TO 1 SNOW RATIO WAS USED BASED ON THE
COBB METHODOLOGY. OBSERVED SNOWFALL SUNDAY AFTN AND SUNDAY NIGHT
WAS IN THIS RANGE. THE NAM CONTINUES TO ADVERTISE POCKETS OF
STRONG FRONTOGENESIS WHICH COULD LEAD TO BANDED SNOW DEVELOPMENT.
THIS HAS BEEN THE OPERATIVE MODE IN MANY INSTANCES OVER THE PAST
36 HOURS HOWEVER THE NAM...ARF AND NMM MODELS HAVE SHOWN POOR
SKILL FORECASTING THE LOCATION OF THESE BANDS.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 350 AM CST MON FEB 24 2014
TEMPS FOR THE END OF FEBRUARY AND INTO MARCH WILL BE DOMINATED BY
COLD ARCTIC AIR WITH WELL BELOW NORMAL READINGS. WEDNESDAY LOOKS
TO BE THE ONLY DAY WE MAY BE WITHIN 10 DEGREES OF NORMAL FOR
HIGHS INTO THE NEXT WEEKEND. ALSO WILL SEE AN ACTIVE PERIOD WITH
SEVERAL CHANCES FOR SNOW THROUGHOUT THE WEEK AND INTO THE
WEEKEND.
TUESDAY WILL SEE ANOTHER DISTURBANCE DRIFTING ACROSS THE SW
PORTIONS OF THE CWA. BATTLE WILL BE BETWEEN RADIATION OF A HIGHER
LATE FEBRUARY SUN ANGLE AND SNOWFALL RATES...ON TOP OF A SNOW
PACK. PLOWED ROADS TODAY FOR THE MOST PART BECAME WET AND IN SOME
AREAS EVEN PARTIALLY DRIED...DESPITE CLOUDY SKIES. THINK CLOUDS
WILL BE THICKER LIMITING SOLAR IMPACT...HOWEVER MODELS ARE ONLY
PRODUCING LIGHT SNOW. DAYTIME SNOW OF A HALF INCH TO 1.5 INCHES
FOR THE MOST PART WITH A 15 TO 1 RATIO...HIGHEST ACROSS THE
SOUTHEASTERN PAN HANDLE AND SW NEB.
BY TUESDAY NIGHT ARCTIC HIGH PRESSURE WILL BE DRIFTING OVERHEAD.
CENTER CROSSES OVER THE CWA BETWEEN 04Z AND 09Z. BY 12Z THE HIGH
WILL BE TO THE SE WITH SOUTHWESTERLY WINDS TO BE ON THE
INCREASING...ALONG WITH WAA. LOWS INITIALLY EXPECTED WITH THE
CENTER OF THE HIGH OVERHEAD...EARLY IN THE NIGHT...HOWEVER WITH
THE EXPECTED SNOW PACK...DECOUPLING WILL KEEP WINDS FROM MIXING TO
THE GROUND UNTIL SUNRISE OR LATER. THIS MAY ALLOW A COUPLE OF
DEGREES FURTHER OF A DROP AFTER CENTER PASSES. EITHER
WAY...EXPECT LOWS TO FALL TO A FEW DEGREES ON EITHER SIDE OF ZERO.
WITH THE WAA FOR WED...HIGHS WILL REBOUND ABOVE FREEZING. WARMEST
GUIDANCE IS INTO THE 40S...HOWEVER THINK SNOW PACK WILL HOLD HIGHS
IN THE 30S.
NEXT COLD FRONT ARRIVES FOR THURSDAY WITH TEMPS TO TAKE A
DOWNWARD TREND. A COUPLE OF REINFORCING COLD FRONT WILL CONTINUE
TO TAKE TEMPS LOWER INTO THE WEEKEND. THIS WILL BE COUPLED WITH
SEVERAL DISTURBANCE TO RIDE ACROSS THE HIGH PLAINS WITH SEVERAL
CHANCES FOR SNOW. SNOW IS NOT EXPECTED TO BE CONSTANT...HOWEVER
CHANCES FOR AT LEAST LIGHT SNOW IN ANY 12 HOURS PERIOD WILL
RESULT IN MANY PERIODS WITH SNOW IN THE FORECAST.
NORMAL HIGHS THIS TIME OF YEAR SHOULD BE INTO THE 40S WITH LOWS
IN THE TEENS. MODELS ARE IN GOOD AGREEMENT WITH HIGHS ONLY IN THE
10S AND 20S FROM FRIDAY THROUGH THE WEEKEND AS THE COLD AIR
BLANKETS MUCH OF THE CONUS. COLDEST GUIDANCE IS THE EC WITH MANY
LOCATIONS NOT WARMING ABOVE SINGLE DIGITS FOR THE WEEKEND. THIS
IS NEARLY 40 DEGREES BELOW NORMAL. SUN ANGLE CONTINUES TO
INCREASE...AND RECORD LOW MAXES ARE IN THE SINGLE DIGITS...SO DO
NOT WANT TO GO WITH THE RECORD COLD FROM THE EC YET...THUS
FORECAST IS FAVORING A SLIGHTLY WARMER GFS AT THIS TIME. HOWEVER
WILL CONTINUE TO KEEP AN EYE ON THIS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 531 AM CST MON FEB 24 2014
MIXED LOCAL LIFR/IFR/MVFR/LOCAL VFR THIS MORNING ARE EXPECTED TO
IMPROVE TO MVFR/VFR THIS AFTERNOON AND TONIGHT.
LOW CIGS AND VSBY ACROSS WRN NEB ARE EXPECTED TO IMPROVE TO VFR
THIS AFTERNOON AS THE RESULT OF A CLEARING LINE THAT IS EXPECTED
TO DEVELOP. THE CLEARING LINE COULD MOVE TO KIEN- KTIF- KLBF
BEFORE AN ARCTIC FRONT SWEEPS IN THIS AFTERNOON AND LOWERS CIGS TO
MVFR. A BAND OF LIGHT SNOW AND MVFR CIGS/VSBY IS EXPECTED TO
DEVELOP LATE THIS AFTERNOON AND THIS EVENING...MAINLY ACROSS WRN
NEB. THIS IS ASSOCIATED WITH THE PASSAGE OF THE ARCTIC FRONT.
SNOW AND MVFR/IFR CIGS ARE EXPECTED TO DEVELOP TODAY...GENERALLY
FROM KIEN-KTIF-KONL NORTHWARD WITH FLIGHT CONDITIONS WORSENING
NORTHWARD. FLIGHT CONDITIONS SHOULD IMPROVE WEST TO EAST LATE THIS
AFTERNOON AS THE DISTURBANCE TRACKING THROUGH SD MOVES EAST OF THE
AREA.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...MASEK
AVIATION...CDC
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
605 AM CST MON FEB 24 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 300 AM CST MON FEB 24 2014
...CURRENTLY AS OF 09Z...
WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED RIDGING ALONG
THE U.S. WEST COAST NORTHWARD THROUGH ALASKA...WHILE TROUGHING
DOMINATED FROM THE NORTH POLE SOUTHWARD THROUGH MUCH OF CANADA AND
THE NORTHERN TIER OF THE U.S.. WITHIN THIS TROUGHING...THERE ARE 3
IMPORTANT SHORTWAVE TROUGHS OF NOTE FOR THE FORECAST...
1. OVER SOUTHERN SASKATCHEWAN INTO NORTHWEST MONTANA...EXPECTED
TO BRING THE SNOW LATE TODAY INTO TONIGHT. DPVA AND ISENTROPIC
LIFT AHEAD OF THIS SHORTWAVE HAS SUPPORTED LIGHT SNOW ACROSS MUCH
OF MONTANA SOUTHEAST INTO NEBRASKA.
2. ALONG THE NUNAVUT/NORTHWEST TERRITORIES BORDER IN CANADA...
EXPECTED TO BRING THE ARCTIC COLD SHOT TO THE AREA TUESDAY NIGHT.
IN ITS WAKE SURFACE TEMPERATURES RANGE FROM A BITTER 20 TO 30
BELOW ZERO.
3. RIGHT NEAR THE NORTH POLE...SPECIFICALLY 84 N / 130 W...EXPECTED
TO BRING THE ARCTIC AIR FOR THURSDAY INTO THE WEEKEND. IN ITS
WAKE... 925MB TEMPS RANGE FROM -28 TO -34C PER GFS ANALYSIS.
OVER THE FORECAST AREA...SKIES REMAIN CLEAR DUE TO PLENTY OF DRY AIR
AS SEEN ON THE 00Z MPX SOUNDING. SOME CIRRUS IS BEGINNING TO
ENCROACH FROM THE WEST...THOUGH. TEMPERATURES HAVE SLOWLY COOLED
THROUGH THE NIGHT RESULTING FROM A WESTERLY BREEZE...WITH READINGS
IN THE LOWER SINGLE DIGITS.
... FORECAST ...
MODELS ARE IN GOOD AGREEMENT MARCHING THE FIRST SHORTWAVE TROUGH
INTO THE EASTERN DAKOTAS BY 00Z...OVER THE FORECAST AREA BY 06Z AND
INTO LOWER MICHIGAN BY 12Z TUE. 275-280K ISENTROPIC LIFT PROGS
SUGGEST THAT TO GET THE SNOW OVER MONTANA AND NEBRASKA INTO THE
FORECAST AREA...WE HAVE TO WAIT FOR THE SHORTWAVE TROUGH TO ARRIVE.
THIS IS WHY MODELS SLOWED DOWN OVER THE PAST FEW DAYS OF BRINGING
SNOW TO THE AREA. THE BEST LIFT...ALBEIT WEAK...IS PROGGED OVER THE
SOUTHWESTERN HALF OF THE FORECAST AREA BETWEEN 01-06Z...THEN SHIFTS
TO FAR SOUTHWEST WI BETWEEN 06-09Z BEFORE EXITING. PRECIPITATION
CHANCES HAVE BEEN ADJUSTED TO FIT THE TIMING OF THE LIFT SIGNAL.
STILL DOES NOT LOOK LIKE THERE WILL BE MUCH SNOW GIVEN THE WEAK
NATURE OF THE LIFT...PRECIPITABLE WATER ONLY 0.1-0.2 OF AN
INCH...AND THE SNOW RUNNING INTO THE DRY AIRMASS CURRENTLY IN PLACE.
ANY LIFT TOO IS MOSTLY ABOVE THE DENDRITIC GROWTH ZONE. PREVIOUS
FORECAST AMOUNTS OF LESS THAN 1 INCH SEEM REASONABLE.
REGARDING TEMPERATURES. 925MB READINGS AT 18Z TODAY ARE SIMILAR TO
YESTERDAY AT 18Z...BETWEEN -13 AND -16C. ONLY DIFFERENCES BETWEEN
TODAY AND YESTERDAY IS MORE CLOUD COVER AND STARTING OFF COLDER...
WHICH SHOULD KEEP HIGHS A LITTLE COOLER. IN THE WAKE OF THE
SHORTWAVE TROUGH PASSAGE TONIGHT...925MB TEMPS COOL TO -14 TO -19C.
A NORTHWEST BREEZE COMBINED WITH CLOUDS SHOULD HELP TO HOLD LOWS UP
SOMEWHAT...BUT READINGS SHOULD FALL INTO THE SINGLE DIGITS ABOVE AND
BELOW ZERO THROUGH ADVECTION...COLDEST OVER THE NORTHWEST HALF OF
THE FORECAST AREA.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 300 AM CST MON FEB 24 2014
THE BIG IMPACT STORY HERE IS THE COLD...
SHORTWAVE TROUGH CURRENTLY OVER THE NUNAVUT/NORTHWEST TERRITORIES
REGION IS PROGGED TO DROP THROUGH THE FORECAST AREA LATE
TUESDAY...USHERING IN THE FIRST SURGE OF BITTER COLD ARCTIC AIR.
TROUGH SHOULD GO THROUGH PRECIP FREE WITH JUST SOME CLOUDS. 925MB
TEMPS PLUMMET TO -21 TO -24C BY 06Z WEDNESDAY...SENDING SURFACE
TEMPERATURES DOWN BELOW ZERO. WITH THE COLD AIR FIRMLY ENTRENCHED
FOR 06-12Z...TEMPERATURES SHOULD IN MOST LOCATIONS DIP INTO TEENS
BELOW ZERO. MOS GUIDANCE WIND FORECASTS SUGGEST THE TYPICAL COLD
SPOTS COULD DECOUPLE...THUS HAVE THEM APPROACHING 20 BELOW. A WIND
CHILL ADVISORY IS A GIVEN FOR TUESDAY NIGHT INTO WEDNESDAY MORNING.
A BRIEF BREAK IN THE COLD AIR COMES WEDNESDAY AFTERNOON AS WESTERLY
WINDS INCREASE AND PULL IN SOME DOWNSLOPED AIR OFF THE ROCKIES. THIS
INCREASE IS A RESULT OF THE NEXT SHORTWAVE TROUGH NEAR THE NORTH
POLE DROPPING INTO THE MN ARROWHEAD. 925MB WINDS APPROACH 45-50 KT
AT 00Z THURSDAY WEST OF THE MISSISSIPPI RIVER...BRINGING UP CONCERN
OF A POSSIBLE WIND ADVISORY. HOWEVER...A STRONG INVERSION LOOKS TO
DEVELOP TO PRECLUDE MIXING THOSE HIGHER WINDS DOWN. IT STILL WILL BE
BRISK...THOUGH...AND STRONG ENOUGH TO RESULT IN SOME BLOWING AND
DRIFTING OF SNOW IN OPEN AREAS.
NEXT ARCTIC COLD SHOT WHICH IS MUCH MORE IMPRESSIVE COMES IN LATE
WEDNESDAY NIGHT. THE AFOREMENTIONED NORTH POLE SHORTWAVE CROSSES
UPPER MICHIGAN WEDNESDAY NIGHT...DRAGGING AN ARCTIC COLD FRONT
THROUGH THE FORECAST AREA. A STRONG PRESSURE RISE IS PROGGED BEHIND
THIS FRONT WHICH SHOULD RESULT IN A PERIOD OF BRISK NORTHWEST WINDS.
THEN 925MB TEMPS PLUMMET TO -23 TO -27C AT 12Z THURSDAY. DID NOT GO
AS COLD AS THESE WOULD SUGGEST GIVEN THE LATE ARRIVAL OF THE COLD
AIR AND PLENTY OF WIND. STILL...THE WIND CHILLS ARE PLENTY LOW
ENOUGH FOR AN ADVISORY.
THURSDAY AND THURSDAY NIGHT LOOK DOWNRIGHT COLD. 850MB TEMP
ANOMALIES ARE PROGGED BETWEEN 2.5-3 STANDARD DEVIATIONS BELOW
NORMAL...SUGGESTING RECORD TERRITORY. IN ADDITION...HIGH PRESSURE
SETTLES OVERHEAD THURSDAY NIGHT...SETTING UP POTENTIAL FOR
TEMPERATURES TO TANK. ONLY CAVEAT WILL BE SOME INCREASING MID/HIGH
CLOUDS LATER THURSDAY NIGHT. SOME WISCONSIN COLD SPOTS COULD DIP TO
30 BELOW OR COLDER...AS INDICATED BY THE MEX GUIDANCE.
FOR FRIDAY THROUGH MONDAY...THE FORECAST AREA WILL BE IN-BETWEEN
ARCTIC COLD UPPER TROUGHING ENCOMPASSING MUCH OF SOUTHERN CANADA AND
SHORTWAVE TROUGHS TRAVERSING THE SOUTHERN 2/3 OF THE U.S.. AT THE
SAME TIME AT THE SURFACE...ARCTIC HIGH PRESSURE SHOULD BE IN PLACE
FOR MUCH OF THE TIME. ONE SHORTWAVE MAY BRING SOME LIGHT SNOW TO
LOCATIONS SOUTH OF I-90 ON FRIDAY...IF IT CAN MAKE IT THROUGH THE
DRY AIR. ONLY KEPT 20 PERCENT CHANCES IN FOR THIS TIME PERIOD. SAME
HOLDS TRUE FOR ANOTHER SHORTWAVE TROUGH GOING BY SATURDAY NIGHT INTO
SUNDAY...THOUGH THE TRACK IS A BIT FARTHER NORTH SO CHANCES ARE A
LITTLE HIGHER. TEMPERATURES WILL STAY WELL BELOW NORMAL BEING UNDER
THE INFLUENCE OF THE ARCTIC SURFACE HIGH...THOUGH SOME GRADUAL
MODERATION SHOULD TAKE PLACE AS THE EARLY MARCH SUN WORKS ON THE
AIR. MORE WIND CHILL ADVISORIES ARE LIKELY...THOUGH...ESPECIALLY
FRIDAY NIGHT INTO SATURDAY MORNING.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 605 AM CST MON FEB 24 2014
VFR CONDITIONS WILL CONTINUE TODAY AS COLD...DRY CANADIAN HIGH
PRESSURE REMAINS OVER THE AREA. A SHORTWAVE TROUGH DROPPING ACROSS
THE DAKOTAS TODAY WILL SPREAD INCREASING/LOWERING CLOUDS INTO THE
AREA LATE THIS AFTERNOON BUT CIGS WILL REMAIN AOA 10K FT. THE TROUGH
WILL SLIDE ACROSS THE AREA THIS EVENING. LIFT WITH THIS FEATURE WILL
BE ON THE WEAK SIDE AND THE QUESTION REMAINS WILL THE LIFT BE ENOUGH
TO OVERCOME THE DRIER LOW LEVEL AND PRODUCE SOME -SN AT THE TAF
SITES. MODEL CONSENSUS HAS THE LIFT OVERCOMING THE DRY AIR AT KRST
WITH A PERIOD OF MVFR/IFR CIGS/VSBYS IN -SN AS THE TROUGH MOVES BY.
KLSE REMAINS ON THE EDGE OF WHERE LIFT APPEARS TO BE ENOUGH TO
OVERCOME THE DRY AIR AND ONLY INCLUDED A PERIOD OF P6SM -SN AT KLSE.
MODEL SOUNDINGS SHOWING SOME MOISTURE/SATURATION TO LINGER ACROSS
THE AREA LATER TONIGHT...TRAPPED UNDER AN INVERSION NEAR 925MB.
CARRIED BKN CIGS IN THE 2K-3K RANGE AT THE TAF SITES AFTER THE -SN
MOVES OUT.
&&
.CLIMATE...
ISSUED AT 300 AM CST MON FEB 24 2014
GIVEN ALL THE COLD AIR TO ROUND OUT THE MONTH OF FEBRUARY...HERE IS
HOW FEBRUARY AND THE WINTER OVERALL WOULD STACK UP COMPARED TO
RECORDS BASED ON THE CURRENT FORECAST...
...FOR THE MONTH OF FEBRUARY...
LA CROSSE... 9.3 AVERAGE TEMPERATURE...3RD COLDEST
COLDER FEBRUARYS...
1873... 3.9
1936... 4.3
ROCHESTER... 6.7 AVERAGE TEMPERATURE...4TH COLDEST
COLDER FEBRUARYS...
1936... 0.5
1979... 5.7
1917... 6.0
...FOR THE WINTER...DECEMBER THROUGH FEBRUARY...
LA CROSSE... 11.5 AVERAGE TEMPERATURE...5TH COLDEST
COLDER WINTERS...
1872-1873... 8.4
1874-1875... 10.5
1977-1978... 11.4
1935-1936... 11.4
ROCHESTER... 8.8 AVERAGE TEMPERATURE...5TH COLDEST
COLDER WINTERS...
1978-1979... 5.6
1886-1887... 5.9
1935-1936... 8.1
1977-1978... 8.7
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM....AJ
AVIATION.....RRS
CLIMATE......AJ/RRS
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1025 AM MST MON FEB 24 2014
.UPDATE...
&&
.SHORT TERM...FOG HAS BEEN STEADILY DISSIPATING ACROSS THE
NORTHEAST PLAINS...WITH INCREASED VISIBILITIES. STILL A WEAK
CYCLONE NORTH OF DENVER KEEPING LOW CLOUDS AND FOG IN AN AREA FROM
NORTH OF BOULDER TO FORT COLLINS EASTWARD ACROSS CENTRAL WELD AND
MORGAN COUNTIES. VISIBILITIES IN THIS AREA AROUND A MILE. ALLOWED
THE DENSE FOG ADVISORY TO EXPIRE AT 9AM. FOG WILL GRADUALLY
DISSIPATE THROUGH THE MORNING AS WEST NORTHWEST FLOW ALOFT MIXES
TO THE SURFACE WITH GUSTY WINDS SPREADING OFF THE FOOTHILLS.
LATEST MODELS SHOW THE NEXT FRONTAL SURGE MOVING ACROSS THE
PLAINS AFTER 20Z...REACHING DENVER AROUND 23Z WITH A SHIFT IN THE
WINDS TO THE NORTHEAST. FRONT LOOKS TO BE NEAR CASPER AT THIS
TIME. CURRENT FORECASTS HAVE SIMILAR THINKING THOUGH MAY DELAY THE
WIND SHIFT AN HOUR OR TWO. LOW CLOUDS AND STRATUS LOOK TO DEVELOP
AROUND 00Z. CHANCE FOR SNOW ACROSS THE MOUNTAINS THIS EVENING WITH
APPROACHING TROUGH AND LIFT. WON`T CHANGE MUCH TO ONGOING
FORECASTS AT THIS TIME. WILL BOOST TEMPERATURES A BIT ACROSS THE
DENVER AREA BASED ON CURRENT READINGS.
.AVIATION...WESTERLY WINDS OFF FOOTHILLS HAVE PUSHED ACROSS THE
DENVER AREA WITH GUSTS TO 26 KTS. LATEST RAP AND HRRR SHOW THE
WINDS SHIFTING TO THE NORTHWEST AT 18Z. MAY DELAY THIS WIND SHIFT
AN HOUR BASED ON CURRENT CONDITIONS. OTHERWISE CURRENT TAF TRENDS
SEEM ON TRACK. FRONT LOOKS TO MOVE ACROSS THE DENVER AREA AROUND
23Z...WILL DELAY THIS WIND SHIFT AN HOUR. IFR CONDITIONS TO
DEVELOP BY 01Z BEHIND THE FRONT WITH SNOW POSSIBLE LATE TUESDAY
MORNING...CONTINUING THROUGH THE AFTERNOON. AT THIS TIME...IT
LOOKS LIKE AROUND AN INCH OF ACCUMULATION BY TUESDAY EVENING.
&&
.PREV DISCUSSION... /ISSUED 400 AM MST MON FEB 24 2014/
SHORT TERM...SHALLOW FOG/STRATUS LAYER COVERS THE PLAINS EXCEPT
FOR A LITTLE HOLE IN DOWNSLOPE OVER DOUGLAS AND ELBERT COUNTIES.
SOME SIGNS OF STIRRING IN THIS LAYER AS WINDS ON THE PLAINS
INCREASE...SURFACE VISIBILITIES HAVE STARTED TO COME UP IN SOME
AREAS THIS LAST HOUR. HOWEVER A WEAK DENVER CYCLONE REMAINS IN
PLACE WITH LIGHT WINDS IN THE SOUTH PLATTE VALLEY AND WEST TOWARD
THE FOOTHILLS. NO REAL CLEARING FROM THE WEST YET...WEST WINDS ARE
CREEPING INTO THE LOWER FOOTHILLS SOUTH OF BOULDER...BUT MAKING
LESS PROGRESS FURTHER NORTH PROBABLY DUE TO SOME HELP FROM THE
CYCLONE CIRCULATION AND THE SE GRADIENT ON THE PLAINS. ALREADY
DELAYED CLEARING IN THE DENVER AREA A COUPLE OF HOURS. EXTENDED
THE DENSE FOG ADVISORY UNTIL 9 AM...THINGS WILL PROBABLY BE BETTER
IN DENVER A COUPLE HOURS EARLIER...BUT NOT SURE THERE WILL BE MUCH
IMPROVEMENT IN FORT COLLINS/LONGMONT/GREELEY TRIANGLE.
COMPLICATED SCENARIO FOR THE REST OF THE DAY AS WELL...AND LOW
CONFIDENCE THAT THE MODELS HAVE A GOOD HANDLE ON ALL THINGS
HAPPENING NEAR THE SURFACE. PLAINS SOUTHERLIES WILL TRY TO
MAINTAIN THE CURRENT SITUATION UNDER A STRONG INVERSION. MEANWHILE
WESTERLIES IN A WEAK MOUNTAIN WAVE WILL BE TRYING TO BREAK THROUGH
THE WEST EDGE OF THE COLD AIR. STILL THINK THE WESTERLIES WILL
PUSH OFF THE FOOTHILLS...AT LEAST INTO DENVER BUT AGAIN LESS
CERTAINTY FURTHER NORTH. WE MAY WIND UP WITH TWO OR THREE AREAS OF
CHANNELED WESTERLIES WITH COLD AIR IN THE VALLEYS IN BETWEEN. THEN
A FEATURE THAT IS NOT WELL REPRESENTED IN THE MODELS NOW ACROSS
SOUTHERN WYOMING SHOULD MOVE OVER DENVER AROUND MIDDAY. THIS WILL
LIKELY BRING A SHIFT TO A MORE NW WIND DIRECTION IN THE WARMER AIR
AND BRING SLIGHT COOLING. IT MAY ALSO INITIATE A PREFRONTAL
SOUTHWESTWARD SURGE IN THE COLD AIR. THEN THE REAL FRONT WILL PUSH
SOUTH LATER IN THE AFTERNOON. THIS APPEARS TO HAVE A PRETTY GOOD
PRESSURE WAVE BUILDING UP...WE WILL NOT HAVE THE NEAR ZERO AIR
THAT IS BEHIND THE BOUNDARY NOW...BUT STILL A PRETTY STOUT LITTLE
WAVE OF WIND AND TEMPERATURE GRADIENT WILL COME THROUGH IN THE
LATE AFTERNOON AND EARLY EVENING. THEN BACK TO LIGHTER EASTERLY
WINDS BY MIDNIGHT OR SO.
TOO MUCH TO TRY TO PIN DOWN ALL THESE LITTLE DETAILS EXACTLY...BUT
EVEN THE WARM AIR SHOULD NOT BE QUITE AS WARM AS WE EXPECTED AND
THE EARLIER SURGE AND SLIGHTLY EARLIER TIMING OF THE REAL FRONT
MEANS I NEED TO TRIM TEMPERATURES FOR TODAY. I SUBTRACTED A FEW
DEGREES IN THE WARMER AIR...AND MOVED THE NORTH/SOUTH GRADIENT
SOUTHWARD AS WELL...THEN SHOWED A BIT MORE COOLING LATE IN THE
DAY. WITH THE DRY AIR ALOFT SIGNIFICANT SNOW DOES NOT LOOK
LIKELY...BUT THE STRATUS WILL RETURN WITH THE FRONT AND THERE
COULD BE SOME FLURRIES WITH IT...AT THIS POINT THE EXISTING POPS
SEEM ALRIGHT.
LONG TERM...AN UPPER LEVEL TROUGH WILL MOVE ACROSS NRN CO TUE AFTN
INTO TUE EVENING. MEANWHILE A STG CDFNT WILL MOVE ACROSS NERN CO
BY MIDDAY ENHANCING UPSLOPE FLOW. CROSS-SECTIONS SHOW DECENT
MOISTURE IN THE MTNS TUE AFTN INTO EARLY TUE EVENING WITH DECENT
OROGRAPHICS SO SHOULD SEE A PERIOD OF SNOW WITH CLOSE TO ADVISORY
AMOUNTS IN SOME AREAS. OVER NERN CO COMBINATION OF INCREASING
UPSLOPE FLOW...SOME MDT MID LVL QG ASCENT AND POTENTIAL CSI SHOULD
LEAD TO A GOOD CHANCE OF SNOW BY EARLY TUE AFTN NR THE WY-NE
BORDER WHICH WILL SPREAD SOUTHWARD ACROSS THE PLAINS BY LATE AFTN.
APPEARS SNOW SHOULD GRADUALLY END BY EARLY TUE EVENING FM NORTH TO
SOUTH AS AS UPSLOPE FLOW WEAKENS AND DRIER AIR SPREADS ACROSS.
OVERALL AMOUNTS WILL BE IN THE 1 TO 3 INCH RANGE ALTHOUGH BANDED
PCPN COULD LEAD TO SOME 2 TO 4 INCH AMOUNTS IN SOME PLACES. HIGHS
ON TUE WILL OCCUR IN THE MORNING AND THEN STEADILY DROP IN THE
AFTN AS COLDER AIR MOVES IN BEHIND COLD FNT.
FOR WED MAINLY DRY WNW FLOW ALOFT WILL BE OVER THE AREA WITH ONLY A
SLIGHT CHC OF SNOW IN THE MTNS. HIGHS SHOULD MODERATE SOME OVER
NERN CO ALTHOUGH SNOW COVER COULD ALTER READINGS IN SOME AREAS
ESPECIALLY OVER THE FAR NERN CORNER. WILL KEEP HIGHS IN THE MID TO
UPPER 40S ALONG THE FRONT RANGE WITH UPPER 30S OVER THE FAR NERN
CORNER. BY THU THE FLOW ALOFT WILL BECOME MORE WLY AS A WEAK UPPER
LEVEL TROUGH MOVES ACROSS BY THU AFTN INTO THU NIGHT. CROSS-
SECTIONS SHOW MOISTURE INCREASING OVER THE AREA WHICH SHOULD LEAD TO
A GOOD CHANCE OF SNOW IN THE MTNS. AT LOWER ELEVATIONS SFC LOW PRES
WILL EXTEND FM SCNTRL WY INTO SERN CO WITH INCREASING SELY LOW LVL
FLOW OVER NERN CO AS COLDER AIR TRIES TO BACKDOOR INTO THE FAR NERN
CORNER. AS THE WK UPPER LEVEL TROUGH MOVES ACROSS THU NIGHT THERE
COULD BE A CHC OF SNOW ESPECIALLY OVER THE FAR NERN PLAINS. HIGHS
ON THU MAY RISE INTO THE LOWER 50S NEAR DENVER HOWEVER OVER THE
FAR NERN CORNER READINGS MAY HOLD IN THE 30S.
BY FRI THE FLOW ALOFT WILL BE WLY WITH CROSS-SECTIONS SHOWING
LIMITED MOISTURE OVER THE AREA SO WILL JUST MENTION A CHC OF LIGHT
SNOW IN THE MTNS. AT LOWER ELEVATIONS BOTH THE ECMWF AND GFS SHOW A
CDFNT BACKDOORING ACROSS MOST OF NERN CO BY AFTN WITH READINGS ONLY
IN THE LOWER 30S ALONG THE WY-NE BORDER. CLOSER TO THE FOOTHILLS
TEMP FCST WILL BE MORE DIFFICULT AS SHALLOW LYR OF COLD AIR BATTLES
DOWNSLOPE WLY FLOW COMING OFF THE HIGHER TERRAIN. FOR NOW WILL KEEP
READINGS IN THE LOWER TO MID 40S OVER DENVER. AS FOR PRECIP WILL
MENTION A SLIGHT CHANCE OF SNOW ALONG THE WY-NE BORDER PUT KEEP THE
REST OF THE PLAINS DRY.
FOR SAT INTO SAT NIGHT AN UPPER LEVEL TROUGH MAY MOVE ACROSS THE
AREA IN WLY FLOW ALOFT LEADING TO A GOOD CHANCE OF SNOW IN THE
MTNS. AT LOWER ELEVATIONS THE LOW LEVEL FLOW EAST OF THE MTNS IS
FCST TO BE SELY AS COLD SFC HIGH PRES SLIDES FM THE NRN ROCKIES
INTO THE CNTRL PLAINS. IF THE FLOW IS SELY THAT WOULD KEEP THE
BEST CHC OF SNOW NR THE WY-NE BORDER. HOWEVER IF THE FLOW ENDS UP
MORE ELY THEN THAT WOULD ENHANCE PCPN CHANCES FURTHER SOUTH. FOR
NOW WILL KEEP CHC POPS NEAR THE WY-NE BORDER WITH LOWER POPS
FURTHER SOUTH. AS FOR HIGHS WILL HAVE READINGS IN THE LOWER TO MID
30S AROUND DENVER WITH ONLY LOWER TO MID 20S OVER THE FAR NERN
CORNER.
AVIATION...VISIBILITIES WILL CONTINUE TO IMPROVE OVER THE NEXT
COUPLE HOURS WITH STRATUS DRIFTING OUT OF THE DENVER AREA BY 14Z.
VFR CONDITIONS EXPECTED MOST OF THE DAY...THEN MVFR/IFR
CONDITIONS REDEVELOPING BEHIND A COLD FRONT BETWEEN 22Z AND 02Z.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...D-L
LONG TERM....RPK
AVIATION...D-L
AREA FORECAST DISCUSSION
NWS ALBANY NY
424 PM EST MON FEB 24 2014
.SYNOPSIS...
AN ARCTIC AIR MASS WILL BE IN PLACE THIS WEEK WITH BELOW NORMAL
TEMPERATURES. A SERIES OF DISTURBANCES ASSOCIATED WITH AN UPPER
LEVEL LOW WILL PRODUCE SCATTERED SNOW SHOWERS AND FLURRIES INTO THE
MID WEEK. A CLIPPER LOW ON WEDNESDAY WILL PRODUCE MORE WIDESPREAD
SNOW SHOWERS...AS IT PASSES ACROSS THE SOUTHERN QUEBEC AND NORTHERN
NEW YORK BORDER...WITH A REINFORCING SHOT OF ARCTIC AIR.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
AS OF 423 PM EST...A BROAD H500 UPPER LEVEL LOW WILL IMPACT THE
NORTHEAST THROUGH THE WEEK WITH SEVERAL SURGES OF ARCTIC AIR. THE
UPPER LEVEL TROUGH IS AN EXTENSION OF THE POLAR VORTEX. ONE CLOSED
H500 CIRCULATION IS OVER N-CNTRL QUEBEC. ANOTHER POTENT SHORT-WAVE
MOVING S/SE IN THE TROUGH IS APPROACHING FROM NEAR ND/NW MN BASED
ON THE LATEST WV LOOP. SOME OF THE SHORT-WAVE ENERGY FROM THE
DISTURBANCE WILL BE THE CLIPPER FOR LATE TUE NIGHT INTO WED TO
IMPACT THE REGION.
CYCLONIC FLOW ALOFT WILL DOMINATE WITH SEVERAL SFC TROUGHS MOVING
THROUGH THE LONGWAVE TROUGH. ONE MOVED THROUGH THE REGION THIS
AFTERNOON WITH MAINLY DIFFUSE ACTIVITY DUE TO THE STEEP MID LEVEL
LAPSE RATES...AS H500 TEMPS ARE IN THE -35C TO -37C RANGE. THERE
WAS AN ORGANIZED BAND OF SNOW SHOWERS THAT WAS IMPACTING THE WRN
MOHAWK VALLEY THAT BROKE UP AS IT MOVED EAST.
THE LAKE EFFECT SNOW ADVISORY WAS CANCELLED FOR NRN HERKIMER
CTY...SINCE THE BEST ORGANIZED LAKE BAND LATE THIS AFTERNOON AND
TONIGHT LOOKS TO IMPACT SRN HERKIMER CTY. THE INVERSION HEIGHTS ARE
MARGINAL UPSTREAM AT KSYR/KRME/KUCA AT 6-7 KFT AGL WITH A 280-290
DEG LOW-LEVEL TRAJ. THE INSTABILITY CLASS IS CONDITIONAL TO
MODERATE WITH THE POSSIBILITY OF A LAKE BAND EXTENDING DOWNSTREAM
INTO SRN HERKIMER SUPPORTED BY THE LOCAL HIRESWRF COLUMNAR REF
PRODUCT BTWN 21Z-03Z. THE LATEST HRRR 3-KM REF PRODUCT ALSO KEYS
INTO THIS AREA. AN ADDITIONAL 2 TO 6 INCHES IS POSSIBLE FOR
PORTIONS OF SOUTHERN HERKIMER CTY...WITH TOTALS OF 3 TO 8 INCHES
MENTIONED IN THE STATEMENT. ONLY AN ADDITIONAL INCH OR TWO IS
POSSIBLE FOR THE WRN DACKS...AND MOSTLY OF THE OPEN CELLULAR SNOW
SHOWER ACTIVITY. GENERALLY...SLIGHT TO LOW CHC POPS HAVE BEEN USED
PRIOR TO MIDNIGHT NORTH AND WEST OF THE MID HUDSON VALLEY AND NW
CT...WITH THE BEST CHCS OF SNOW SHOWERS WEST OF THE HUDSON RIVER
VALLEY AFTER MIDNIGHT.
H850 TEMPS WILL BE IN THE -17C TO -20C RANGE WITH THE COLD
ADVECTION IN THE WAKE OF THE SFC TROUGH. EXPECT LOWS TO BE IN THE
UPPER SINGLE DIGITS AND TEENS FROM THE CAPITAL DISTRICT SOUTH AND
EAST...WITH SINGLE DIGITS TO A FEW BELOW ZERO READINGS /SRN DACKS/ OVER
THE NRN TIER. BRISK W/NW WINDS WILL GENERATE WIND CHILLS 10 TO 15
BELOW ZERO OVER THE SRN DACKS...AND GENERALLY 5 BELOW TO 5 ABOVE
IN MOST OTHER LOCATIONS.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/...
TUESDAY...ANY ORGANIZED LAKE EFFECT ACTIVITY DIMINISHES DUE TO THE
LOWERING INVERSION. HOWEVER...LAKE MOISTURE WILL STILL BE
UTILIZED...AS A WEAK MID LEVEL DISTURBANCE MAY FOCUS ISOLATED TO
SCATTERED SNOW SHOWERS AGAIN DURING DURING THE MORNING INTO THE
AFTERNOON...WITH THE BETTER CHANCE OF SNOWFALL IN THE AFTERNOON
ALONG THE WRN SPINE OF THE WRN DACKS...SRN GREENS...NRN-CNTRL
TACONICS AND BERKSHIRES. THE WESTERLY UPSLOPE SNOW SHOWERS AND
FLURRIES MAY PRODUCE LIGHT SNOW AMOUNTS OF A COATING TO AN INCH OR
TWO. H850 TEMPS WILL BE RUNNING 1 TO 2 STANDARD DEVIATIONS BELOW
NORMAL ACCORDING TO THE LATEST GEFS. TEMPS WILL STILL RUN ABOUT 10
DEGREES OR SO BELOW NORMAL. OUR FORECAST FAVORS THE COLD NAM MOS
MAX TEMPS WITH TEENS OVER THE SRN DACKS. LOWER TO M20S OVER THE
REST OF THE FCST AREA...EXCEPT U20S OVER THE MID HUDSON
VALLEY...SRN TACONICS...AND NW CT.
TUE NIGHT...A CLIPPER LOW APPROACHES FROM THE NRN GREAT LAKES
REGION...AND SE ONTARIO. THIS CLIPPER WILL TAP SOME LAKE EFFECT
MOISTURE...AS THE FLOW BACKS TO SOUTHWEST. THERE IS SOME SYNOPTIC
LIFT WITH THIS SYSTEM. OROGRAPHIC AND LOW-LEVEL CONVERGENCE MAY
PROMOTE A PERIOD OF LIGHT SNOW ESPECIALLY NORTH AND WEST OF THE
CAPITAL REGION. A BURST OF LAKE EFFECT OR LAKE ENHANCED SNOWFALL
MAY OCCUR OVER THE WRN DACKS/WRN MOHAWK VALLEY AROUND MIDNIGHT AND
THEREAFTER. 1-4 INCHES OF SNOWFALL MAY BE POSSIBLE...ESPECIALLY
OVER THE WRN DACKS BY WED MORNING. WITH THE WEAK THERMAL
ADVECTION...SLIGHT OR LOW CHANCES OF SNOW SHOWERS SPREAD EASTWARD
ACROSS THE FCST AREA AFTER MIDNIGHT. LOWS WILL RANGE FROM THE
SINGLE DIGITS OVER THE NW PORTION OF THE FCST AREA TO TEENS FROM
THE MOHAWK VALLEY/CAPITAL REGION SOUTH AND EAST.
WED-WED NIGHT...THE CLIPPER MOVES N/NE OF NRN NY OVER SRN QUEBEC
BY NOON. ANOTHER LOW PRESSURE SYSTEM FORMS WELL OFF THE MID
ATLANTIC COAST. A PERIOD OF SNOW SHOWERS OR LIGHT SNOW WILL IMPACT
THE REGION DURING THE MORNING INTO THE EARLY PM AHEAD OF THE
ARCTIC FRONT. CHC POPS WERE USED FOR THE ENTIRE AREA. SNOW ACCUMS
OF A COATING TO AN INCH WILL BE POSSIBLE. ARCTIC AIR POURS BACK
INTO THE REGION WITH H850 TEMPS FALLING TO -19C TO -23C OVER THE
FCST AREA...AND THE GEFS INDICATE THESE VALUES WILL BE 2 TO 3
STANDARD DEVIATIONS BELOW NORMAL. THE STRONG COLD ADVECTION SWEEPS
THROUGH BEFORE NIGHTFALL. AFTER HIGHS IN THE TEENS AND 20S WITH
BLUSTERY CONDITIONS...LOWS WILL BE ZERO TO 5 BELOW OVER THE SRN
DACKS AND PARTS OF THE LAKE GEORGE REGION....AND SINGLE DIGITS
ELSEWHERE. UPSLOPE AND LAKE EFFECT SNOW SHOWERS WILL CONTINUE IN
THE AFTERNOON...AND THEN TAPER SNOW SHOWERS NORTH AND WEST OF THE
TRI CITIES WITH ANOTHER DISTURBANCE APPROACHING FROM THE UPPER
GREAT LAKES REGION. WIND CHILLS VALUES MAY NOT HIT ADVISORY LEVELS
WED NIGHT DUE TO A WEAKENING WIND FIELD...BUT MAY HIT ADVISORY
LEVELS OVER SOME OF THE MTN ZONES THU NIGHT/FRI MORNING.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
A SERIES OF EMBEDDED SHORTWAVES WILL MOVE ABOUT THE BASE OF A LARGE
UPPER LEVEL TROUGH THAT WILL PROVIDE CHANCES OF SOME PRECIPITATION
THROUGHOUT THE EXTENDED PERIOD. THE UPPER LEVEL FLOW PATTERN WILL
BEGIN TO SLOWLY TRANSITION INTO A ZONAL PATTERN WITH COLD AIR STILL
IN PLACE AS WE GO THE THE END OF THE EXTENDED PERIOD.
THURSDAY INTO FRIDAY...COLD NORTHWESTERLY FLOW WITH BELOW AVERAGE
TEMPERATURES WITH T850 BETWEEN -20C TO -24C AND T925 TEMPS BETWEEN
-16C AND -20C WILL BE LOCKED INTO THE REGION. A NEGATIVE TILTED
SHORTWAVE TROUGH WITHIN THE UPPER LEVEL FLOW WITH THE AXIS OVER THE
NY/CANADA BORDER WILL PROVIDE THE CHANCE OF SNOW SHOWERS ESPECIALLY
AREAS NORTH AND WEST OF THE IMMEDIATE CAPITAL REGION NEAR THE UPPER
LEVEL TROUGH AS WE GO THURSDAY NIGHT INTO FRIDAY MORNING. A STEEP
GRADIENT IN ISOBARS WILL ALSO PRODUCE GUSTY NORTHWEST WINDS
WITH GUSTS NEAR 30 MPH POSSIBLE ESPECIALLY IN THE HIGHEST TERRAIN.
TEMPERATURES ON THURSDAY WILL RANGE FROM THE LOWER 20S TO UPPER 20S
WHICH WILL FALL TO LOWER TEENS IN THE HIGH TERRAIN TO NEAR 20 IN
VALLEY LOCATIONS ON FRIDAY. LOW TEMPERATURES ON THURSDAY WILL BE
VERY COLD WITH VALUES RANGING FROM 10 BELOW TO NEAR ZERO IN THE HIGH
TERRAIN TO AROUND ZERO TO 5 ABOVE FOR THE VALLEY AREAS.
FRIDAY NIGHT THROUGH MONDAY...COLD AIR FROM CANADA WITH
NORTHWESTERLY WINDS WILL CONTINUE WITH SERIES OF UPPER LEVEL TROUGHS
CONTINUING TO MOVE WEST TO EAST ACROSS OUR AREA WITH AREAS OF WEAK
HIGH PRESSURE IN BETWEEN THE PASSING DISTURBANCES AS THE UPPER LEVEL
WAVE OSCILLATES AROUND THE LARGE UPPER LEVEL LOW IN NORTHERN QUEBEC.
THE NEXT CHANCE OF SNOW SHOWERS ACCORDING TO THE LATEST 12Z MODELS
AND NUMERICAL GUIDANCE WILL BE DURING THE DAY ON SATURDAY AS ANOTHER
WAVE OF LOW PRESSURE MOVES RIGHT OVER OUR REGION ACCORDING TO THE
LATEST TRENDS. CHANCE OF SNOW SHOWERS WILL BE IN THE FORECAST AT
THIS TIME AS THE TRACK AND INTENSITY AGREEMENT BETWEEN THE MODELS
SHOW LOW CONFIDENCE AT THIS TIME. A SURFACE HIGH PRESSURE WILL WORK
INTO THE AREA ON SUNDAY GIVING TRANQUIL WEATHER CONDITIONS. AS WE GO
INTO MONDAY...THE MODELS DO DIFFER IN OUR NEXT WEATHER SYSTEM WITH
ITS TRACK AND INTENSITY. THIS WILL HAVE TO BE MONITORED WITH FUTURE
UPDATES TO THE FORECAST. HIGH TEMPERATURES FROM SATURDAY INTO MONDAY
WILL REMAIN BELOW AVERAGE WITH TEMPERATURES RANGING FROM THE MID
TEENS TO MID 20S. LOW TEMPERATURES WILL ALSO BE VERY COLD FOR THIS
TIME OF YEAR WITH TEMPERATURE 10 BELOW ZERO TO NEAR ZERO FOR THE
LAKE GEORGE SARATOGA REGION POINTS NORTH AND WEST AND ALSO IN THE
HIGH TERRAIN OF NEW ENGLAND AND WITH LOW TEMPERATURES OF 0 TO 5 IN
THE IMMEDIATE CAPITAL REGION AND VALLEY LOCATIONS.
&&
.AVIATION /21Z MONDAY THROUGH SATURDAY/...
SOME LAKE EFFECT/ENHANCED SNOW SHOWERS/FLURRIES MAY REACH
KGFL/KALB/KPSF AT TIMES THIS AFTERNOON. MAINLY VFR CONDITIONS ARE
EXPECTED...BUT ANY SNOW SHOWER ACTIVITY COULD PRODUCE BRIEF PERIODS
OF MVFR/IFR...ESP FOR VSBYS. THE SNOW SHOWER THREAT SHOULD END AT
KGFL THIS EVENING. THE SCATTERED SNOW SHOWER THREAT SHOULD CONTINUE
AT KALB AND KPSF THROUGH TONIGHT DUE TO THE WIND DIRECTION NEARLY
PARALLELING THE MOHAWK VALLEY AND INTO THE BERKSHIRES...OSCILLATING
NORTH AND SOUTH WITH SUBTLE WIND SHIFTS. STILL...VFR CONDITIONS
SHOULD DOMINATE ALL TAF SITES THROUGH TOMORROW MORNING OUTSIDE OF
ANY BRIEF SNOW SHOWERS.
WEST TO NORTHWEST WINDS AT 13-18 KT WITH GUSTS OF 20-30 KT ARE
EXPECTED THIS AFTERNOON. THE STRONGEST GUSTS ARE EXPECTED FROM
KALB-KPSF IN THE FAVORED W-NW FLOW. THESE BRISK WINDS WILL PERSIST
THROUGH EARLY MONDAY EVENING...BEFORE GRADUALLY DIMINISHING AFTER
05Z-08Z/TUE TO 5-10 KT. WEST WINDS SHOULD CONTINUE TOMORROW MORNING
AT AROUND 10 KT.
OUTLOOK...
TUESDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHSN.
WEDNESDAY: MODERATE OPERATIONAL IMPACT.WINDY WITH A CHANCE OF
SHSN.
WEDNESDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
THURSDAY: MODERATE OPERATIONAL IMPACT.BREEZY CHANCE OF SHSN.
THURSDAY NIGHT: LOW OPERATIONAL IMPACT.BREEZY NO SIG WX.
FRIDAY: NO OPERATIONAL IMPACT. NO SIG WX.
FRIDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN.
SATURDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHSN.
&&
.HYDROLOGY...
AN ARCTIC AIR MASS WILL REMAIN ACROSS THE HYDRO SERVICE AREA FOR
THE ENTIRE WEEK WHICH WILL ALLOW ICE TO REFORM...THICKEN...AND
STRENGTHEN ON AREA RIVERS AND LAKES THROUGH THE WEEK. LIGHT
PRECIPITATION IS EXPECTED DURING THE WEEK...AND ANY THAT DOES
OCCUR WILL BE IN THE FORM OF SNOW SHOWERS OR LIGHT SNOW. NO HYDRO
IMPACTS ARE EXPECTED ON THE MAIN STEM RIVERS THE NEXT 5 DAYS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...LAKE EFFECT SNOW ADVISORY UNTIL 6 AM EST TUESDAY FOR NYZ038.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...11/WASULA
NEAR TERM...WASULA
SHORT TERM...WASULA
LONG TERM...LFM
AVIATION...NAS
HYDROLOGY...11/WASULA
AREA FORECAST DISCUSSION
NWS TAUNTON MA
1242 PM EST MON FEB 24 2014
.SYNOPSIS...
A STRONG COLD FRONT WAS EXITING THE REGION EARLY THIS MORNING...
BRINGING PROGRESSIVELY COLDER CONDITIONS THROUGH NEXT WEEKEND.
MAINLY DRY CONDITIONS WILL BE IN PLACE AS LARGE HIGH PRESSURE
MOVES ACROSS. ONE EXCEPTION WILL BE FOR THE RISK OF ACCUMULATING
SNOWFALL FOR WEDNESDAY AS LOW PRESSURE DEVELOPS WELL SOUTH OF NEW
ENGLAND. ANOTHER LOW MAY BRING SOME SNOWFALL NEXT WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
1240 PM UPDATE...
DECENT COVERAGE OF STRATO CU ACROSS SNE EXCEPT FOR FAR SE MA AND
CAPE/ISLANDS. LOW AND MID LEVEL MOISTURE COMBINED WITH STEEP LOW
LEVEL LAPSE RATES RESPONSIBLE FOR THE CLOUDS. HIRES MODELS
CONTINUE TO SHOW POTENTIAL FOR A FEW SNOW SHOWERS ACROSS NORTHERN
ZONES THIS AFTERNOON ALTHOUGH LOW DEWPOINTS WILL LIMIT AREAL
COVERAGE. NEAR STEADY TEMPS WITH GUSTY WINDS.
PREVIOUS DISCUSSION...
POST FRONTAL STRATO-CU FILLING BACK IN ACROSS THE INTERIOR AS LOW
AND MID LEVEL MOISTURE FROM THE N SPILLS INTO THE REGION AND
EXPECT SCT-BKN CU TO DEVELOP IN THE COASTAL PLAIN. STEEP LOW LEVEL
LAPSE RATES AND LOW LEVEL MOISTURE SUPPORT A FEW FLURRIES OR SNOW
SHOWERS...ESPECIALLY N OF THE PIKE WHERE HRRR IS TARGETING. STRONG
COLD AIR ADVECTION WILL RESULT IN TEMPS REMAINING NEARLY STEADY OR
PERHAPS FALLING A FEW DEGREES ALONG WITH GUSTY W/NW WINDS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
TONIGHT...
NOT TOO MUCH CHANGE FROM THE DAY AS CYCLONIC CURVATURE...DECENT
SFC PRES GRADIENT AND TRAPPED MID LVL MOISTURE REMAIN IN PLAY
ACROSS THE AREA. THEREFORE..EXPECT AT LEAST SOME CLOUDS AND WINDS
TO REMAIN THROUGH THE OVERNIGHT HOURS. WHILE THIS WILL LIMIT THE
ABILITY TO RADIATE...NORMAL DIURNAL TRENDS SHOULD STILL ALLOW MINS
INTO THE LOW TEENS AND 20S. WITH WINDS OF AROUND 10 MPH STILL
POSSIBLE...THIS WOULD YIELD SOME WIND CHILLS BELOW ZERO FOR
PORTIONS OF THE INTERIOR AND IN THE SINGLE DIGITS CLOSER TO THE
SHORELINES.
TUESDAY...
A COLD AND BRISK START IS EXPECTED AS WINDS CONTINUE TO GUST UP TO
ABOUT 20 MPH AFTER SUNRISE AND MIXING SETS UP. ANOTHER ROUND OF
PARTLY CLOUDY CONDITIONS AND HIGHER SUN ANGLES SHOULD ALLOW HIGHS
TO INCREASE INTO THE MID 20S TO LOW 30S DESPITE THIS COOLER START
BUT WITH WIND CHILL VALUES IN THE TEENS TO LOW 20S. MAINLY DRIER
WX AS NOSE OF HIGH PRES BEGINS TO BUILD OVER FROM THE
SW...LIMITING THE POTENTIAL FOR MORE FLURRY ACTIVITY IN COMPARISON
TO MON.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
HIGHLIGHTS...
* JANUARY-LIKE TEMPERATURES THIS WEEK AND AS WE ENTER MARCH NEXT
WEEKEND
* RISK FOR ACCUMULATING SNOW WED AND AGAIN NEXT WEEKEND
* OTHERWISE MAINLY DRY CONDITIONS PREVAIL
SYNOPTIC OVERVIEW...
NOT MUCH CHANGE IN THE FORECAST FROM PREVIOUS DAYS. HIGH AMPLITUDE
NORTHERN STREAM PATTERN DEVELOPS WITH POLAR VORTEX BEING DISPLACED
SOUTHWARD INTO ONTARIO BY THU. THIS RESULTS IN A STEADY STREAM OF
ARCTIC AIR INTO SOUTHERN NEW ENGLAND THIS WEEK AND INTO NEXT
WEEKEND. THAT/S THE EASY PART OF THE FORECAST. WHAT BECOMES
DIFFICULT TO NAIL DOWN AT THIS TIME RANGE IS THE INTENSITY AND TRACK
OF ANY EAST CYCLOGENESIS...AS ARCTIC SHORT WAVES PIVOT AROUND THE
SOUTHERN BASE OF THE POLAR VORTEX. FURTHER COMPLICATING THE FORECAST
IS IF PACIFIC ENERGY UNDERCUTTING THE WESTERN RIDGE INTERACTS
/PHASING VS UNPHASED/ WITH ARCTIC SHORT WAVE TROUGHS ALONG THE EAST
COAST.
MODEL PREFERENCES AND SENSIBLE WEATHER...
WEDNESDAY...00Z DETERMINISTIC GFS AND ECMWF IN AGREEMENT ON AN
UNPHASED SOLUTION WITH NORTHERN STREAM LOW MOVING ACROSS SOUTHEAST
CANADA AND EAST COAST CYCLOGENESIS TRACKING WELL SOUTHEAST OF
40N/70W BENCHMARK. HOWEVER APPEARS THERE WILL BE ENOUGH MID LEVEL
LIFT TO INDUCE AN INVERTED SURFACE TROUGH BETWEEN THESE TWO LOWS TO
GENERATE A FEW TENTHS OF QPF OVER SOUTHERN NEW ENGLAND. THUS A LOW
TO MODERATE RISK OF A FEW FLUFFY INCHES OF SNOW...WITH HIGHEST RISK
OVER SOUTHEAST MA.
HOWEVER CAN/T COMPLETELY RULE OUT A STRONGER/PHASED SOLUTION AS
ARCTIC SHORT WAVE/PV ANOMALY THAT INDUCES EAST COAST CYCLOGENESIS
IS CURRENTLY MOVING ACROSS NORTHWEST CANADA EARLY THIS MORNING.
MODELS LIKELY NOT SAMPLING THIS PACKET OF JET ENERGY VERY WELL
GIVEN THIS IS A DATA SPARSE AREA. THUS WILL HAVE TO WAIT UNTIL
THIS FEATURE ENTERS SOUTHERN CANADA BEFORE MODELS BEGIN BETTER
SAMPLING OF THIS JET ENERGY. IF THIS SHORT WAVE TROUGH IS MORE
AMPLIFIED THAN MODELS CURRENTLY SIMULATE...A TRACK CLOSER TO THE
COAST IS PLAUSIBLE. THEREFORE ITS STILL TOO EARLY TO LOCK INTO A
SINGLE SCENARIO. HOWEVER FOR THE MOMENT WILL PLAY THE MOST LIKELY
SCENARIO...A LOW TO MODERATE RISK OF A FEW INCHES OF FLUFFY SNOW.
THURSDAY THRU SUNDAY...ANOTHER ARCTIC FRONT MOVES ACROSS THE AREA
THU OR FRI WITH GEFS AND ECENS ENSEMBLE POST FRONTAL 850 MEAN TEMPS
VARYING FROM -15C TO -20C ACROSS SOUTHERN NEW ENGLAND. THUS COLDER
THAN NORMAL TEMPS HOWEVER ANY RECORD BREAKING COLD SHOULD REMAIN
WEST OF NEW ENGLAND ACROSS THE GREAT LAKES GIVEN PROXIMITY OF COLD
AIR CORE. WILL ALSO HAVE TO WATCH FOR POTENTIAL SNOW SQUALLS ALONG
AND AHEAD OF FRONTAL BOUNDARY...AS INCREASING SUN ANGLE /SAT MAR
1ST/ AND COLD AIR ALOFT WILL YIELD STEEP LOW LEVEL LAPSE RATES.
THEN NEXT WEEKEND THE FOCUS WILL BE ON PACIFIC ENERGY MARCHING
ACROSS THE SOUTHERN STATES AND ITS POSSIBLE INTERACTION/PHASING WITH
THE NORTHERN STREAM OVER THE NORTHEAST. THE 00Z GEFS AND ECENS
ENSEMBLE MEAN ARE WELL OFFSHORE WITH ANY CYCLOGENESIS...AS WELL AS
THE 00Z GFS. THE 00Z ECMWF IS MUCH CLOSER TO THE COAST BUT ALSO
WEAKER. GIVEN THE UNCERTAINTY WILL CONTINUE WITH CHANCE POPS FOR
NEXT WEEKEND.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH TUESDAY NIGHT/...
HIGH CONFIDENCE. MAINLY VFR THROUGH THE PERIOD WITH OCCASIONAL
CIGS 040-080. A FEW LIGHT SNOW SHOWERS POSSIBLE THIS AFTERNOON
NORTH OF THE PIKE AND AGAIN TUE AFTERNOON. W/NW WIND GUSTS TO 25
KT THIS AFTERNOON DIMINISHING TONIGHT...THEN 20-25 KT TUE.
KBOS TERMINAL...HIGH CONFIDENCE IN TAF.
KBDL TERMINAL...HIGH CONFIDENCE IN TAF.
OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...
VFR ALONG WITH GUSTY WNW WINDS. THE EXCEPTION WILL BE WED WHEN WINDS
WILL BRIEFLY RELAX. HOWEVER A PERIOD OF SNOW IS POSSIBLE WED WITH
MVFR CONDITIONS. HIGHEST PROBABILITY OF SNOW AND MVFR CONDITIONS IS
ACROSS SOUTHEAST MA WED.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
THROUGH TUESDAY...HIGH CONFIDENCE.
W-NW WINDS WILL BE INCREASING THROUGH THE DAY TODAY WITH GUSTS
WIDESPREAD 25-30 KT EXPECTED. A FEW GUSTS MAY APPROACH GALE
FORCE...BUT THE MAJORITY SHOULD REMAIN BELOW. THESE WINDS WILL
MAINTAIN THROUGH THE OVERNIGHT HOURS TONIGHT...ONLY DIMINISHING
INTO THE MORNING HOURS FOR TUE THEN DROPPING BELOW SMALL CRAFT
THRESHOLDS BY THE LATE DAY TUE.
WITH INCREASING WINDS EXPECT SEAS TO BUILD AS WELL...REACHING
5-7FT AT TIMES MAINLY ON THE OCEAN WATERS.
OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...
GUSTY WNW WINDS AND PERIODS OF FREEZING SPRAY ARE EXPECTED AS ARCTIC
AIR OVERSPREADS THE REGION. WINDS BRIEFLY RELAX WED AS ONE AREA OF
LOW PRES TRACKS ACROSS SOUTHEAST CANADA AND A POTENTIAL GALE CENTER
PASSES SOUTHEAST OF 40N/70W BENCHMARK. A PERIOD OF SNOW WITH REDUCED
VSBY IS LIKELY WED ESPECIALLY OVER THE WATERS SOUTHEAST OF
NANTUCKET.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 1 PM EST TUESDAY FOR ANZ230>237-251.
SMALL CRAFT ADVISORY UNTIL 7 PM EST TUESDAY FOR ANZ250-254>256.
&&
$$
SYNOPSIS...NOCERA/DOODY
NEAR TERM...KJC
SHORT TERM...DOODY
LONG TERM...NOCERA
AVIATION...KJC/NOCERA
MARINE...NOCERA/DOODY
AREA FORECAST DISCUSSION
NWS MIAMI FL
246 PM EST MON FEB 24 2014
.DISCUSSION...
A WEAK COLD FRONT CURRENTLY DRAPED ACROSS NORTHERN FLORIDA IS
EXPECTED TO SLOWLY PUSH TO THE SOUTH THROUGH THE AFTERNOON AND
EVENING. AS IT DOES...A FEW SHOWERS AND POSSIBLY AN ISOLATED
THUNDERSTORM OR TWO MAY DEVELOP ACROSS MAINLY THE EAST COASTAL AREAS
ENHANCED BY A WEAK SEA BREEZE THAT MAY DEVELOP. LATEST HRRR WINDS
DEPICT A WEAK SEA BREEZE ALONG MAINLY THE BROWARD AND PALM BEACH
COUNTY COASTS.
MODELS DEPICT THE COLD FRONT AND ACCOMPANYING DEEPER MOISTURE FIELD
TO BECOME NEARLY STATIONARY ACROSS SOUTH FLORIDA THROUGH TUESDAY
WITH RAIN CHANCES REMAINING ALONG WITH LIGHT AND VARIABLE WINDS.
KEPT SLIGHT CHANCES FOR THUNDERSTORMS TUESDAY AFTERNOON ALONG THE
NORTHERN INTERIOR AND EAST COAST AS WELL WITH THE LINGERING BOUNDARY
IN THE AREA. BY TUESDAY NIGHT INTO EARLY WEDNESDAY...THE FRONT IS
EXPECTED TO BASICALLY WASH OUT IN PLACE. FLOW WILL THEN QUICKLY
BECOME SOUTHWEST AND INCREASE LATE WEDNESDAY OUT AHEAD OF ANOTHER
COLD FRONT POSITIONED ACROSS THE NORTHERN GULF OF MEXICO. THIS FRONT
LOOKS TO BE A BIT STRONGER THAN THE LAST ONE AND SHOULD PUSH THROUGH
SOUTH FLORIDA BY EARLY THURSDAY MORNING WITH BETTER CHANCES FOR
SHOWERS. DID NOT INCLUDE A THUNDER MENTION AT THIS TIME DUE TO THE
TIMING OF THE FRONT BEING DURING THE EARLY MORNING HOURS...ACCORDING
TO THE ECMWF. THE GFS SOLUTION IS A BIT SLOWER BRINGING THE FRONT
INTO SOUTH FLORIDA LATER IN THE AFTERNOON. IF THIS SOLUTION PANS
OUT...THE COMBINATION OF FRONTAL FORCING AND DAYTIME HEATING WOULD
YIELD THUNDERSTORM DEVELOPMENT. WILL NEED TO WATCH SUBSEQUENT MODEL
RUNS CLOSELY FOR TIMING CHANGES.
SHOWERS WILL LINGER THROUGH FRIDAY BEFORE DRY WEATHER RETURNS FOR
THE WEEKEND. UPPER RIDGING WILL THEN BUILD ACROSS THE AREA FROM THE
SOUTH KEEPING TEMPERATURES ABOVE NORMAL.
&&
.AVIATION...
VFR CONDITIONS WILL PREVAIL THROUGH THE FORECAST ALTHOUGH THERE
COULD BE A BRIEF MVFR CIG/VSBY IN A FAST MOVING SHOWER AFT 20Z
THROUGH THIS EVENING. A COLD FRONT NORTH OF LAKE OKEECHOBEE WILL
KEEP SOUTH FLORIDA IN A GENERAL SW-W SURFACE WIND AND IT APPEARS
THE FLOW IS TOO STRONG TO ALLOW A SEA BREEZE TO DEVELOP ALONG THE
EAST COAST. SURFACE WIND BECOME L/V AFT 03Z.
&&
.MARINE...
WINDS OF 10 KNOTS OR LESS ARE EXPECTED TO CONTINUE ACROSS THE
REGIONAL WATERS WITH SEAS OF 2 FEET OR LESS. A COLD FRONT IS
FORECAST TO AFFECT THE REGIONAL WATERS EARLY THURSDAY WITH AN
INCREASE IN WINDS AND SEAS EXPECTED. HOWEVER...HAZARDOUS SEAS ARE
NOT FORECAST FOR THIS PERIOD.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 67 81 63 82 / 20 30 10 20
FORT LAUDERDALE 69 82 66 82 / 20 30 10 20
MIAMI 69 83 67 83 / 20 30 10 20
NAPLES 64 79 62 80 / 10 20 - 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...10/CD
AVIATION/RADAR...30/KOB
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
338 PM EST MON FEB 24 2014
.SYNOPSIS...
HIGH PRESSURE BUILDS ACROSS THE AREA TONIGHT INTO TUESDAY. LOW
PRESSURE MOVES NORTHEAST ALONG THE MID ATLANTIC COAST LATE TUESDAY
NIGHT INTO WEDNESDAY. HIGH PRESSURE RETURNS FOR LATE IN THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
LATEST SFC ANALYSIS REVEALS ~1029 MB LO PRES CENTERED OVR THE
MIDWEST AND A COLD FRNT PUSHING WELL OFF THE MID ATLANTIC CST.
TIGHT PRES GRADIENT BETWEEN THESE TWO FEATURES HAS LED TO WNW
WINDS GUSTING TO 20-30 MPH OVR THE MID ATLANTIC. THESE WINDS WILL
DIMINISH FOLLOWING SUNSET WHILE HI PRES BLDS IN FRM THE WEST.
EXPECT SOME INCREASING CLOUDS TNGT DUE TO INCREASING LO-LEVEL WAA
AND MOISTURE ADVECTION WITHIN THE PROGRESSIVE WLY FLOW ALOFT.
TEMPS WILL BE SLGTLY BLO NORMAL...WITH LOWS IN THE MID 20S TO LWR
30S.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY/...
SHORT TERM PERIOD WILL FEATURE UPR-LEVEL LO PRES CENTERED ACROSS
CNTRL/ERN CANADA WITH CYCLONIC FLOW OVR THE ERN CONUS. APPROACHING
MID-LEVEL SHORTWAVE TROF AND INCREASING MOISTURE WILL LEAD TO
20-30% POPS OVR FAR NRN AREAS TUE. BEST FORCING ASSOCIATED WITH
THE TROF WILL PASS NORTH OF THE AREA. MODEL THICKNESSES AND SFC
TEMPS SUPPORT A RAIN/SNOW MIX...WITH JUST SNOW OVR NRN EDGES OF
THE FA. NO ACCUMULATIONS EXPECTED. OTHERWISE...EXPECT LGT WINDS
WITH A MSTLY CLOUDY SKY AND HIGH TEMPS RANGING FRM THE LO/MID 40S
NORTH TO UPR 40S/LWR 50S SOUTH.
FOR TUE NGT...ATTENTION TURNS TO AN APPROACHING (STRONGER)
SHORTWAVE TROF. COMBO OF DECENT MID/UPR-LEVEL FORCING AND MOISTURE
INCREASE WILL LEAD TO ANOTHER CHANCE FOR PRECIP ACROSS THE MID
ATLANTIC. LO TEMPS NEAR/BLO FREEZING IN MANY SPOTS AND CRASHING
THICKNESSES WILL ALLOW FOR THE CHANCE OF SNOW OVR MOST OF THE
AREA. DO THINK THAT SOME RAIN WILL BE MIXING IN OVR THE MID
SECTION OF THE FA...WITH MSTLY A RAIN EVENT FOR THE TIDEWATER/NE
NC. WITH THIS EVENT BEING SHORT IN DURATION AND TEMPS BEING
MARGINAL (I.E. MELTING ISSUES)...ONLY EXPECTING ACCUMULATIONS FOR
AREAS MAINLY NORTH OF RIC...THE NRN NECK AND THE LWR ERN SHORE. A
COATING TO ONE INCH IS PSBL. THE BULK OF THE PRECIP WILL FALL FRM
9-15Z WED...WITH CONDITIONS QUICKLY DRYING OUT FRM WEST TO EAST
WED AFTN AS SFC LO PRES DEVELOPS OFFSHORE AND PUSHES EWRD. HIGH
TEMPS IN THE MID 30S TO LWR 40S.
SFC HI PRES BLDS OVR THE SE US WED NGT. WITH CLEARING SKIES AND
LGT WINDS...TEMPS WILL FALL INTO THE UPR TEENS TO LWR 20S. BLO
NORMAL TEMPS CONTINUE INTO THU WITH A SUNNY SKY...HIGHS ONLY IN
THE 40S.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
COLDER WITH BELOW NORMAL TEMPS. A SPLIT FLOW WILL LEAD TO QUICK
SYSTM MOVEMENTS AND PERIODIC PCPN CHCS THRU PRD. LEANED TOWARD THE
ECMWF WITH RESPECT TO SFC FEATURES.
CANADIAN HIGH PRESSURE KEEPS IT DRY BUT COLD FRIDAY. LOWS THURS
NIGHT IN THE L-M20S XCPT A FEW UPR TEENS NRMLY COLDER SPOTS. HIGHS
FRI M30S-L40S. NEXT IN A SERIES OF SRN STREAM S/W`S PROGGED TO TRACK
ACROSS THE SOUTHERN MID ATLNTC REGION FRI NIGHT AND SAT. LATEST MODEL
GUIDANCE WANTS TO SHEAR THE PCPN OUT AS IT CROSSES THE MTS FRI NIGHT
WHILE TRACKING AN AREA OF MSTR FROM SRN VA ACROSS THE CAROLINAS LATE
FRI NITE AND SAT MORN. UPSHOT HERE WILL BE YET ANTHR SYSTM WITH LGT
AMOUNTS OF QPF. P-TYPE ISSUES ARISE GIVEN SFC TMPS AOB FREEZING AND
CRITICAL THICKNESSES. WILL CARRY LOW CHC POPS FOR SNOW NWRN HALF OF
FA...A BUFFER ZONE OF SNOW/SLEET DOWN TO VA/NC BORDER WITH A RAIN
SLEET MIX ACROSS NC LATE FRI NITE. LOWS M20S-L30S. CHC LIQUID POPS
ACROSS SERN SCTNS OF FA WITH A BUFFER ZONE OF MIXED RAIN/SNOW FRTHR
NW SAT MORNING. PCPN ENDS MOST AREAS ARND NOON XCPT SOME LINGERING
RAIN CHCS AT THE COAST SAT AFTRN. HIGHS IN THE 40S.
ANTHR CANADIAN HIGH PRESSURE BUILDS INTO THE AREA SAT NIGHT THROUGH
SUNDAY NITE. DRY AND COLD WITH LOWS SAT NITE UPR TEENS-M20S. HIGHS
SUN M-U30S. LOWS SUN NIGHT IN THE 20S.
MODELS INDCTG ANTHR COMPLICATED SYSTM POISED TO MAKE A BEELINE FOR
THE MID ATLNTC RGN MONDAY. HIGH PRS TO THE NORTH ALLOWS FOR A WEDGE
TO SET UP AHEAD OF A MOISTURE LADEN SYSTM DVLPNG ACROSS THE DEEP
SOUTH. THE LOW PROGGED TO LIFT NORTH ACROSS THE RGN LATE MONDAY
ALONG WITH A COLD FRONTAL PASSAGE. MOISTURE PROGGED TO RIDE UP OVER
THE WEDGE PRODUCING A VARIETY OF WX ACROSS THE RGN SUN NITE AND MON
MORN WITH PCPN BCMG RAIN OVR ERN HALF OF FA MON. TO ERLY TO GET
SPECIFIC...BUT THIS SYSTM DOES BEAR WATCHING FOR THE PTNTL OF A
WINTER MIX OF PCPN SUNDAY NIGHT THROUGH MONDAY MORN. LOWS SUN NITE
25-30. HIGHS MON IN THE 30S AND 40S.
&&
.AVIATION /20Z MONDAY THROUGH SATURDAY/...
NW WIND SHOULD AVERAGE 8-12KT...WITH GUSTS TO AROUND 20KT AT
RIC/SBY. HIGH PRESSURE BUILDS ACROSS THE REGION TONIGHT AND MOVES
OFFSHORE TUESDAY.
A LOW PRESSURE SYSTEM DEVELOPS OFF THE MID ATLANTIC COAST TUESDAY
NIGHT AND WEDNESDAY. THIS HAS THE POTENTIAL TO BRING REDUCED
CIGS/VSBY IN A PERIOD OF -SN AT RIC/SBY AND A MIX OF -RA/SN AT
PHF/ORF/ECG...BEFORE POSSIBLY ENDING AS -SN AS FAR SE AS ECG.
ADDITIONALLY...A GUSTY NW WIND IS EXPECTED...ESPECIALLY NEAR THE
COAST. HIGH PRESSURE RETURNS WEDNESDAY AFTERNOON THROUGH FRIDAY.
&&
.MARINE...
WINDS STILL GUSTING TO ARND 25 KTS ACROSS NRN CSTL WTRS SO WILL KEEP
CURRENT SCA HEADLINE UP EXPECTING THE WINDS WILL DIMINISH THRU THE
EVE HOURS. RUC INDCTG A WEAK NRTH SURGE DOWN THE BAY THIS EVE BUT
EXPECT WINDS TO REMAIN BLO 20 KTS. OTW...HIGH PRESSURE BUILDS ACROSS
THE MARINE AREA TUE WITH A NORTH WIND BCMG SE AT SPEEDS BLO SCA LVLS.
LOW PRESSURE EXITS MOVES OFF THE CAROLINA COAST ERLY WED. STRONG CAA
BEHIND THIS SYSTM WILL LIKELY LEAD TO A PRD OF SCA`S FOR WINDS WED
AFTRN AND EVE. FLOW THEN BECOMES SW THURSDAY AS WEAK HIGH PRESSURE
MOVES OFF THE COAST. CANADIAN HIGH PRESSURE BUILDS SOUTH ACROSS THE
AREA FRI. DATA SUGGESTS ANTHR CAA SURGE ERLY FRI.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 1 AM EST TUESDAY FOR ANZ650.
SMALL CRAFT ADVISORY UNTIL 7 PM EST THIS EVENING FOR ANZ652.
&&
$$
SYNOPSIS...MAS
NEAR TERM...MAS
SHORT TERM...MAS
LONG TERM...MPR
AVIATION...AJZ/DAP
MARINE...MPR
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
407 PM EST MON FEB 24 2014
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 357 PM EST MON FEB 24 2014
12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW PERSISTENT...COLD
NW FLOW DOMINATING THE GREAT LKS BTWN RDG ALONG THE W COAST AND
CLOSED LO OVER QUEBEC/TROF IN ERN NAMERICA. COMBINATION OF SHRTWV
EMBEDDED IN NW FLOW ALF...DEEPER MSTR SHOWN ON THE 12Z INL RAOB...
H85 TEMPS IN THE -18C TO -21C RANGE AND SOME OPEN WATER ON LK SUP
HAS RESULTED IN SOME GENERALLY LGT LES IN AREAS FAVORED BY THE LLVL
WNW FLOW. OVER THE INTERIOR...SOME DIURNAL CU/SC HAVE DVLPD IN
RATHER MOIST AIRMASS WITH INCRSG SUN ANGLE CAUSING SOME LLVL
DESTABILIZATION. BTWN THE SHRTWV MOVING THRU THE UPR LKS EARLY THIS
AFTN AND ANOTHER STRONGER DISTURBANCE STRETCHING FM NEAR LK WINNIPEG
INTO THE NRN PLAINS/ACCOMPANYING -SN MOVING THRU THE DAKOTAS...
SHRTWV RDG/AXIS OF DRIER MID LVL AIR IS BRINGING GENERALLY MOSUNNY
WX TO MUCH OF MN EXCEPT THE ARROWHEAD. YET ANOTHER SHRTWV IS
DROPPING SWD FM THE NW TERRITORIES OF CANADA INTO NRN SASKATCHEWAN/
MANITOBA.
MAIN FCST CONCERNS IN THE SHORT TERM INVOLVE LES TRENDS AND TEMPS
ASSOCIATED WITH THE STEADY PARADE OF DISTURBANCES EMBEDDED IN NW
FLOW ALF.
TNGT...WITH APRCH AND PASSAGE OF SHRTWV RDG LATER THIS AFTN AND THIS
EVNG/ACCOMPANYING DEEP LYR QVECTOR DVGC AND SUBSIDENCE...EXPECT
LINGERING LES TO AT LEAST DIMINISH IN INTENSITY/COVERAGE FOR A TIME.
BUT AS SHRTWV NOW MOVING INTO THE NRN PLAINS SHIFTS TO THE SE
TNGT...AREA OF ACCOMPANYING DEEP LYR QVECTOR CNVGC/MORE MSTR AND SFC
COLD FNT ARE FCST TO IMPACT THE AREA MAINLY AFT MIDNGT. ALTHOUGH ALL
MODELS SHOW THE ACCOMPANYING SYNOPTIC SCALE PCPN PASSING TO THE S OF
THE CWA CLOSER TO CORE OF UPR DVGC ON CYC SIDE OF H3 JET MAX...
EXPECT AN INCRS IN LES COVERAGE NEAR LK SUP OVERNGT. TEMPS COULD
FALL OFF QUICKLY THIS EVNG OVER AT LEAST THE INTERIOR NEAR THE WI
BORDER AS AXIS OF DRIER AIR AT LEAST BRIEFLY MOVES OVHD BEFORE
THICKER CLDS ASSOCIATED WITH DISTURBANCE NEAR LK WINNIPEG ARRIVE
LATER.
TUE...WHILE THERE MAY BE SOME MID LVL DRYING/SUBSIDENCE EARLY ON TUE
WITH A PERIOD OF QVECTOR DVGC FOLLOWING THE DEPARTING DISTURBANCE...
SHRTWV NOW DROPPING S INTO SASKATCHEWAN/MANITOBA IS FCST TO BRING A
RETRUN OF MORE DYNAMIC SUPPORT/SOME DEEPER MSTR BY THE AFTN...
ESPECIALLY OVER THE NE HALF OF THE CWA. SO EXPECT INCRSG LES POPS
AGAIN IN THE WNW WIND SN BELTS NEAR THE LK. GIVEN H85 TEMPS FALLING
AOB -25C BY LATE IN THE DAY CAUSING THE NEAR ELIMINATION OF THE DGZ
AS WELL AS CONSIDERABLE ICE COVER OVER LK SUP...EXPECT SN AMOUNTS TO
BE RELATIVELY LIGHT. TUE WL BE ANOTHER UNSEASONABLY COLD DAY. TENDED
TOWARD THE LO END OF GUIDANCE FOR MAX TEMPS.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 406 PM EST MON FEB 24 2014
THE FIRST IN A SERIES OF UPPER LEVEL DISTURBANCES THAT WILL BRING
COLDER AIR TO THE AREA WILL BE SWEEPING ACROSS UPPER MICHIGAN
TUESDAY AFTERNOON AND EARLY TUESDAY EVENING. THIS SHORTWAVE WILL
USHER IN SLIGHTLY COLDER 850MB TEMPS ON TUESDAY NIGHT (-28C) AND
WITH WINDS OUT OF THE NORTHWEST...WOULD EXPECT AT LEAST A BRIEF
PERIOD OF LIGHT TO MODERATE LAKE EFFECT SNOW IN THE NORTHWEST WINDS
SNOW BELTS DURING THE EVENING. BUT MODELS ARE SHOWING DRY AIR ABOVE
850MB MOVING IN QUICKLY AFTER 06Z WEDNESDAY...SO THAT SHOULD CUT OUT
THE INTENSITY HEADING INTO THE OVERNIGHT HOURS. GETTING A GOOD
HANDLE ON ICE COVER OVER THE WESTERN LAKE TODAY...WITH OPEN WATER
GENERALLY NORTHWEST OF A LINE FROM THE APOSTLE ISLANDS TO TERRACE
BAY ONTARIO. THAT GAP OF 30-40MI IS PLENTY TO SUPPORT LAKE EFFECT
CLOUDS AND SNOW...WHICH HAS BEEN SEEN THIS MORNING OVER WESTERN
UPPER MICHIGAN. THEREFORE...WILL CONTINUE TO SHOW LIKELY POPS IN
THE NORTHWEST WIND AREAS OVER THE WEST IN THE EVENING AND DIMINISH
SLIGHTLY OVERNIGHT WITH THE INCREASING DRY AIR AND BACKING WINDS
ASSOCIATED WITH A WEAK HIGH PRESSURE RIDGE. THE EAST IS A LITTLE
MORE COMPLICATED...SINCE THE ONLY POCKET OF OPEN WATER IS THE AREA
TO THE EAST OF THE KEWEENAW PENINSULA AND SOUTH TO MARQUETTE. WITH
THE NORTHWEST WINDS...THAT WOULD SUPPORT THE HIGHEST POPS/AMOUNTS
OVER ALGER COUNTY AND THINK FARTHER EAST INTO LUCE COUNTY (EVEN THE
EASTERN THIRD OF ALGER COUNTY) WOULD SEE LESS ACCUMULATION AND MORE
SCATTERED SNOW SHOWERS WITH THE AMOUNT OF ICE THE BANDS ORIGINATING
NORTHEAST OF ISLE ROYALE WOULD HAVE TO PASS OVER.
THE WEAK HIGH PRESSURE WILL SLIDE ACROSS THE U.P. LATE TUESDAY
NIGHT AND WEDNESDAY MORNING...AS THE NEXT SHORTWAVE AND LOW
PRESSURE SYSTEM DIVE SOUTHEAST OUT OF WESTERN ONTARIO WEDNESDAY
AFTERNOON AND ACROSS LAKE SUPERIOR AT 998MB ON WEDNESDAY EVENING.
THE BEST SNOW ASSOCIATED WITH THIS LOW AND SHORTWAVE WILL LIKELY BE
NEAR THE SURFACE LOW WITH THE LOWER LEVEL DRY AIR BEING PULL
NORTHEAST ACROSS UPPER MICHIGAN. ANY SYNOPTIC SNOW SHOULD BE LIGHT
AND ONLY CREATE A LIGHT DUSTING...MAINLY NEAR LAKE SUPERIOR. BUT
BEHIND THE LOW...EXPECT ANOTHER OPPORTUNITY FOR LAKE EFFECT SNOW IN
NORTHWEST TO NORTH-NORTHWEST WIND AREAS. THE 925MB WINDS WILL BE
FAIRLY STRONG (35KTS) BEHIND THE FRONT AND WILL LIKELY LIMIT THE
RESIDENCE TIME OVER THE 30-40MI STRETCH OF OPEN WATER. WOULD EXPECT
THIS TO LIMIT SNOWFALL AMOUNTS EVEN THOUGH DELTA-T VALUES ARE
NEARING 30-32 AND INVERSION HEIGHTS ARE BETWEEN 10-14KFT. ALTHOUGH
SNOW AMOUNTS MAY NOT BE TOO SIGNIFICANT...THINK THE PERIOD OF VERY
GUSTY NORTHWEST WINDS ON THE BACK SIDE OF THE LOW (GUSTS NEAR LAKE
SUPERIOR OF 30-40KTS NEAR LAKE SUPERIOR FROM ONTONAGON TO WHITEFISH
POINT) WILL CREATE A SIGNIFICANT CONCERN FOR WIDESPREAD BLOWING AND
DRIFTING SNOW. HAVE TRENDED WINDS UP 5-10KTS FOR THIS PERIOD WITH
THE CONSISTENCY IN THE MODELS ON THIS WINDY IDEA. WILL ALSO ADD A
MENTION OF THE POTENTIAL FOR CONSIDERABLE BLOWING AND DRIFTING SNOW
NEAR LAKE SUPERIOR IN THE HWO THAT WILL DEVELOP WEDNESDAY NIGHT
AND CONTINUE INTO THURSDAY MORNING. ADD FINE FLAKE SNOW FALLING WITH
THE BLOWING SNOW SHOULD EASILY CREATE VISIBILITIES OF 1/2MI OR
LESS IN THE KEWEENAW. THE GUSTY WINDS WILL COMBINE WITH TEMPERATURES
BELOW ZERO ON THURSDAY MORNING TO ALSO CREATE A CONCERN FOR WIND
CHILL HEADLINES FOR A GOOD PORTION OF UPPER MICHIGAN. CURRENT
FORECAST HAS WIND CHILL VALUES OF -25 TO -35 DEGREES AND WITH THE
POTENTIAL FOR BLOWING SNOW IT COULD EVENTUALLY BE TIED TOGETHER WITH
A WINTER WX ADVISORY.
ONCE AGAIN...A HIGH PRESSURE RIDGE (FROM A HIGH MOVING INTO THE
UPPER MISSISSIPPI VALLEY) WILL QUICKLY MOVE OVER UPPER MICHIGAN ON
THURSDAY AFTERNOON INTO THURSDAY NIGHT. THIS SHOULD RAPIDLY
DIMINISH WINDS OVER THE AREA DURING THE AFTERNOON. MODELS CONTINUE
TO SHOW HIGHS ONLY REACHING AROUND 0 DEGREES ON THURSDAY...WHICH
WOULD PUT SEVERAL COLD HIGH TEMPERATURE RECORDS IN JEOPARDY SINCE
MOST ARE IN THE MID SINGLE DIGITS ABOVE ZERO. FOR THE LONG PERIOD OF
RECORD SITES...MOST OF THOSE RECORDS DATE BACK TO THE LATE 1800S AND
EARLY 1900S. WOULD EXPECT SKIES TO CLEAR OUT AWAY FROM ANY LAKE
EFFECT NEAR LAKE SUPERIOR THURSDAY AFTERNOON AND CONTINUE INTO
THURSDAY NIGHT. THINK THIS WILL LEAD TO A VERY COLD NIGHT ACROSS THE
AREA AND WILL CONTINUE TO SHOW LOWS IN THE 10S TO MID 20S BELOW ZERO
(COLDEST INTERIOR COLD SPOTS).
ANOTHER SHORTWAVE WILL ROUND THE EASTERN CANADA UPPER TROUGH ON
FRIDAY AND DIVE SOUTHEAST ACROSS UPPER MICHIGAN FRIDAY NIGHT. THE
COLD AIR ASSOCIATED WITH THIS WAVE WILL LEAD TO ANOTHER DAY OF
HIGHS ABOUT 30 DEGREES BELOW NORMAL ON SATURDAY. LAKE EFFECT
POTENTIAL CONTINUES FRIDAY NIGHT INTO SATURDAY...BUT WORRIED THAT
THE VERY COLD TEMPS AND LIGHT WINDS ON THURSDAY NIGHT INTO FRIDAY
WILL LEAD TO A FAST ICE UP OF THE OPEN AREAS AND CUT OFF LAKE
EFFECT. WILL GO WITH SLIGHT AND LOW CHANCE POPS AT THIS POINT DUE TO
THE UNCERTAINTY. EXTENDED MODELS ARE SHOWING A TREND TOWARDS MORE
ZONAL FLOW AND GRADUALLY WARMING TEMPERATURES SUNDAY AND HEADING
INTO NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1222 PM EST MON FEB 24 2014
AS A WEAK SFC HI PRES RDG/DRIER AIR MOVE IN LATE THIS AFTN/EVNG...
EXPECT IMPROVING CONDITIONS AT ALL 3 TAF SITES...TO MVFR AT IWD/CMX
AND VFR AT SAW. BUT ANOTHER DISTURBANCE WL BRING AN UPTICK IN LK
EFFECT SHSN AND BLSN AT IWD/CMX LATER TNGT...WITH VSBYS FALLING INTO
THE IFR RANGE. DOWNSLOPE WIND COMPONENT INTO SAW SHOULD MAINTAIN VFR
WX THERE. ALTHOUGH SOME DRYING IN THE WAKE OF THIS DISTURBANCE MIGHT
CAUSE AN IMPROVEMENT TO MVFR AT IWD ON TUE...DAYTIME HEATING WL
LIKELY RESULT IN AN MVFR CIG AT SAW WITH THE ARRIVAL OF MORE
UNSTABLE AIR. IFR CONDITIONS ARE LIKELY TO PLAGUE THE EXPOSED CMX
LOCATION THRU 18Z TUE UNDER THIS AXIS OF COLDER AIR.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 406 PM EST MON FEB 24 2014
WEST TO NORTHWEST WINDS OF 15-25KTS WILL CONTINUE TONIGHT THROUGH
TUESDAY NIGHT...BUT THEN BACK ON WEDNESDAY MORNING AHEAD OF AN
APPROACHING LOW PRESSURE SYSTEM. A TIGHTENING GRADIENT AHEAD OF
THAT LOW COULD LEAD TO A FEW GALE FORCE GUSTS TO 35KTS AROUND
MID-DAY WEDNESDAY. THEN AS THE LOW DROPS SOUTHEAST ACROSS EASTERN
LAKE SUPERIOR ON WEDNESDAY EVENING...EXPECT A RAPID SWITCH AND
INCREASE IN THE WINDS FROM THE NORTHWEST AND CURRENT THOUGHT IS
THAT MUCH OF THE LAKE WILL SEE GALE FORCE GUSTS TO 35-40KTS. A HIGH
PRESSURE RIDGE WILL QUICKLY MOVE OVER THE AREA THURSDAY
AFTERNOON/NIGHT AND WEAKEN THE WINDS. ANOTHER TROUGH MOVING THROUGH
ON FRIDAY NIGHT WILL INCREASE WINDS BACK TO 15-25KTS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...SRF
AVIATION...KC
MARINE...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
357 PM EST MON FEB 24 2014
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 357 PM EST MON FEB 24 2014
12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW PERSISTENT...COLD
NW FLOW DOMINATING THE GREAT LKS BTWN RDG ALONG THE W COAST AND
CLOSED LO OVER QUEBEC/TROF IN ERN NAMERICA. COMBINATION OF SHRTWV
EMBEDDED IN NW FLOW ALF...DEEPER MSTR SHOWN ON THE 12Z INL RAOB...
H85 TEMPS IN THE -18C TO -21C RANGE AND SOME OPEN WATER ON LK SUP
HAS RESULTED IN SOME GENERALLY LGT LES IN AREAS FAVORED BY THE LLVL
WNW FLOW. OVER THE INTERIOR...SOME DIURNAL CU/SC HAVE DVLPD IN
RATHER MOIST AIRMASS WITH INCRSG SUN ANGLE CAUSING SOME LLVL
DESTABILIZATION. BTWN THE SHRTWV MOVING THRU THE UPR LKS EARLY THIS
AFTN AND ANOTHER STRONGER DISTURBANCE STRETCHING FM NEAR LK WINNIPEG
INTO THE NRN PLAINS/ACCOMPANYING -SN MOVING THRU THE DAKOTAS...
SHRTWV RDG/AXIS OF DRIER MID LVL AIR IS BRINGING GENERALLY MOSUNNY
WX TO MUCH OF MN EXCEPT THE ARROWHEAD. YET ANOTHER SHRTWV IS
DROPPING SWD FM THE NW TERRITORIES OF CANADA INTO NRN SASKATCHEWAN/
MANITOBA.
MAIN FCST CONCERNS IN THE SHORT TERM INVOLVE LES TRENDS AND TEMPS
ASSOCIATED WITH THE STEADY PARADE OF DISTURBANCES EMBEDDED IN NW
FLOW ALF.
TNGT...WITH APRCH AND PASSAGE OF SHRTWV RDG LATER THIS AFTN AND THIS
EVNG/ACCOMPANYING DEEP LYR QVECTOR DVGC AND SUBSIDENCE...EXPECT
LINGERING LES TO AT LEAST DIMINISH IN INTENSITY/COVERAGE FOR A TIME.
BUT AS SHRTWV NOW MOVING INTO THE NRN PLAINS SHIFTS TO THE SE
TNGT...AREA OF ACCOMPANYING DEEP LYR QVECTOR CNVGC/MORE MSTR AND SFC
COLD FNT ARE FCST TO IMPACT THE AREA MAINLY AFT MIDNGT. ALTHOUGH ALL
MODELS SHOW THE ACCOMPANYING SYNOPTIC SCALE PCPN PASSING TO THE S OF
THE CWA CLOSER TO CORE OF UPR DVGC ON CYC SIDE OF H3 JET MAX...
EXPECT AN INCRS IN LES COVERAGE NEAR LK SUP OVERNGT. TEMPS COULD
FALL OFF QUICKLY THIS EVNG OVER AT LEAST THE INTERIOR NEAR THE WI
BORDER AS AXIS OF DRIER AIR AT LEAST BRIEFLY MOVES OVHD BEFORE
THICKER CLDS ASSOCIATED WITH DISTURBANCE NEAR LK WINNIPEG ARRIVE
LATER.
TUE...WHILE THERE MAY BE SOME MID LVL DRYING/SUBSIDENCE EARLY ON TUE
WITH A PERIOD OF QVECTOR DVGC FOLLOWING THE DEPARTING DISTURBANCE...
SHRTWV NOW DROPPING S INTO SASKATCHEWAN/MANITOBA IS FCST TO BRING A
RETRUN OF MORE DYNAMIC SUPPORT/SOME DEEPER MSTR BY THE AFTN...
ESPECIALLY OVER THE NE HALF OF THE CWA. SO EXPECT INCRSG LES POPS
AGAIN IN THE WNW WIND SN BELTS NEAR THE LK. GIVEN H85 TEMPS FALLING
AOB -25C BY LATE IN THE DAY CAUSING THE NEAR ELIMINATION OF THE DGZ
AS WELL AS CONSIDERABLE ICE COVER OVER LK SUP...EXPECT SN AMOUNTS TO
BE RELATIVELY LIGHT. TUE WL BE ANOTHER UNSEASONABLY COLD DAY. TENDED
TOWARD THE LO END OF GUIDANCE FOR MAX TEMPS.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 347 AM EST MON FEB 24 2014
THE 500MB TROUGH WILL LINGER ACROSS E CANADA/E U.S. THROUGH THE
PERIOD. STARTING TUESDAY THE MAIN 500MB LOW SET UP ACROSS HUDSON BAY
WILL EXTEND A LARGE TROUGH FROM SASKATCHEWAN THROUGH THE CENTRAL
PLAINS AND E U.S. EXPECT THE APEX OF THE 500MB TROUGH TO BE ACROSS
THE CWA AT 00Z WEDNESDAY AS THE MAIN LOW SLOWLY SINKS S INTO ONTARIO
AND THE ONTARIO/QUEBEC BORDER THURSDAY. THE CLOSEST THE 500MB LOW
WILL BE TO THE CWA WILL BE WEDNESDAY NIGHT. 500MB TEMPS OF -50C NEAR
THE CENTER OF THE LOW WILL REMAIN TO OUR NE. WHILE SNOW SHOWERS WILL
BE POSSIBLE...MAINLY ALONG LAKE SUPERIOR THROUGH THURSDAY...MUCH OF
THE DISCUSSION BELOW WILL FOCUS ON THE EXTREMELY COLD TEMPERATURES.
COOL NW FLOW WILL BE THE RULE BEHIND THE SFC LOW SWEEPING FROM
NW/CENTRAL ONTARIO AT 18Z WEDNESDAY TO CENTRAL AND NE LAKE SUPERIOR
BY 00Z THURSDAY AND SE QUEBEC EARLY THURSDAY MORNING. THIS WILL
ALLOW THE ARCTIC AIRMASS TO SINK IN AND LINGER THROUGH THE 1ST HALF
OF THE UPCOMING WEEKEND. 850MB TEMPS DURING THIS TIME WILL RANGE
FROM -28 TO -32C. SFC TEMPS WILL GREATLY DEPEND ON CLOUD COVER AND
OPEN WATER ACROSS LAKE SUPERIOR.
COLDEST SFC TEMPS LOOK TO OCCUR FRIDAY MORNING. 2M TEMPS OFF THE
24/00Z GFS SHOW MIN TEMPS OVER N MN AND CENTRAL WI OF -20 TO -30F
/BUT ONLY -5 TO -15F ACROSS UPPER MI/. WITH HIGH PRESSURE NEARLY
OVERHEAD AND WINDS UNDER 5KTS...CONTINUED TO GO ON THE LOW END OF
GUIDANCE. WIND CHILL VALUES WILL NOT BE MUCH LOWER THAN THE ACTUAL
TEMPS THANKS TO THE LIGHT WINDS.
LOW WIND CHILLS ARE INEVITABLE EACH OVERNIGHT/MORNING THROUGH
THURSDAY MORNING. THE LOWEST WIND CHILLS WILL BE LIKELY THURSDAY
MORNING AS UPPER MI RESIDES BETWEEN THE DEEPENED LOW LOVER SE
ONTARIO AND LARGE STRONG HIGH STRETCHING FROM MN TO NW CANADA. A NW
PUFF OF 8-10KTS /STRONGER FROM THE KEWEENAW PENINSULA ALONG THE LAKE
SUPERIOR SHORELINES/ WILL HELP WIND CHILLS FALL TO -20 TO NEARLY
-35F OVER MUCH OF W AND CENTRAL UPPER MI...LOWEST ALONG THE WI
BORDER.
GIVEN ALL THE DISCUSSION ABOUT TEMPERATURES...BELIEVE IT OR
NOT...NORMAL HIGH TEMPS THIS TIME OF YEAR ARE IN THE UPPER 20S AND
LOW 30S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1222 PM EST MON FEB 24 2014
AS A WEAK SFC HI PRES RDG/DRIER AIR MOVE IN LATE THIS AFTN/EVNG...
EXPECT IMPROVING CONDITIONS AT ALL 3 TAF SITES...TO MVFR AT IWD/CMX
AND VFR AT SAW. BUT ANOTHER DISTURBANCE WL BRING AN UPTICK IN LK
EFFECT SHSN AND BLSN AT IWD/CMX LATER TNGT...WITH VSBYS FALLING INTO
THE IFR RANGE. DOWNSLOPE WIND COMPONENT INTO SAW SHOULD MAINTAIN VFR
WX THERE. ALTHOUGH SOME DRYING IN THE WAKE OF THIS DISTURBANCE MIGHT
CAUSE AN IMPROVEMENT TO MVFR AT IWD ON TUE...DAYTIME HEATING WL
LIKELY RESULT IN AN MVFR CIG AT SAW WITH THE ARRIVAL OF MORE
UNSTABLE AIR. IFR CONDITIONS ARE LIKELY TO PLAGUE THE EXPOSED CMX
LOCATION THRU 18Z TUE UNDER THIS AXIS OF COLDER AIR.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 323 AM EST MON FEB 24 2014
NO GALES ARE EXPECTED...BUT SOME HEAVY FREEZING SPRAY IS POSSIBLE IN
ANY OPEN WATERS ON WEDNESDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...KF
AVIATION...KC
MARINE...TITUS
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1153 AM CST MON FEB 24 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 350 AM CST MON FEB 24 2014
1038 MB ARCTIC HIGH PRESSURE ACROSS SRN ALBERTA AND SRN
SASKATCHEWAN WILL MOVE INTO SOUTH DAKOTA BY 12Z TUESDAY MORNING.
AN ARCTIC FRONT ACROSS NRN MT IS EXPECTED TO MOVE INTO THE FCST
AREA BY LATE AFTN AND BE THROUGH THE FCST AREA AND ACROSS KS BY
TUESDAY MORNING. LOWS IN THE SINGLE DIGITS ARE EXPECTED TONIGHT
WITH WIND CHILL READINGS AROUND 10 BELOW TO PERHAPS 15 BELOW ZERO
ACROSS NORTHERN NEB.
THE MODEL CONSENSUS SUGGESTS A PERIOD OF LIGHT SNOW
DEVELOPING...MAINLY ACROSS WRN NEBRASKA...AS THE FRONT MOVES
THROUGH. SNOWFALL AMOUNTS SHOULD BE LESS THAN AN INCH AND MAINLY
A DUSTING.
THERE IS QUITE A VARIETY OF MAX TEMPERATURE FORECASTS TO CHOOSE
FROM TODAY. THE FORECAST FOLLOWS A BLEND OF NAM...GEM REG...ECM
AND MET PLUS BIAS CORRECTION FOR HIGHS IN THE UPPER 20S NORTH TO
UPPER 30S SOUTH. THE NAM IS ACTUALLY FORECASTING MID 40S AT NORTH
PLATTE WHILE THE RAP SHOWS UPPER 20S AND THE ECM MID 30S. THIS IS
A FUNCTION OF THE SKY COVER INDICATED IN THE MODELS AND SOME
SOLNS SHOW A PERIOD OF CLEARING AHEAD OF THE ARCTIC FRONT. THE
MODEL CONSENSUS SUGGESTS CLEARING ACROSS WRN/SWRN
NEB...KAIA-KOGA-KIML AS A RESULT OF SOME SOUTHWEST WINDS
DEVELOPING. EAST OF THAT AREA IT LOOKS LIKE ARCTIC DRAPE SHOULD
CONTINUE WITH SOUTH WINDS.
THE LIGHT TO MODERATE SNOW ON RADAR EARLY THIS MORNING ACROSS
NCNTL NEB IS MOVING RAPIDLY EAST AND SHOULD BE REPLACED BY A
SECOND AREA OF SNOW LATER THIS MORNING A BIT FARTHER NORTH AND
EAST. THIS SNOW IS CURRENTLY SHOWING ON THE KUNR RADAR ACROSS WRN
SD. THE MODELS GENERATE A THIRD AREA OF SNOW THIS AFTERNOON BUT
THIS SHOULD PASS MOSTLY NORTH AND EAST OF THE FORECAST AREA. THIS
AREA OF SNOW IS CURRENTLY ACROSS SERN MT.
BEST SNOWFALL IS EXPECTED ACROSS BOYD COUNTY WITH QPF RANGES FROM
LESS THAN 0.10 INCHES IN THE UKMET...GEF AND GFS TO 0.30 INCHES
IN THE NMM WEST. THIS IS A WIDE RANGE AND THE CONSENSUS IS AROUND
0.15 INCHES. A 15 TO 20 TO 1 SNOW RATIO WAS USED BASED ON THE
COBB METHODOLOGY. OBSERVED SNOWFALL SUNDAY AFTN AND SUNDAY NIGHT
WAS IN THIS RANGE. THE NAM CONTINUES TO ADVERTISE POCKETS OF
STRONG FRONTOGENESIS WHICH COULD LEAD TO BANDED SNOW DEVELOPMENT.
THIS HAS BEEN THE OPERATIVE MODE IN MANY INSTANCES OVER THE PAST
36 HOURS HOWEVER THE NAM...ARF AND NMM MODELS HAVE SHOWN POOR
SKILL FORECASTING THE LOCATION OF THESE BANDS.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 350 AM CST MON FEB 24 2014
TEMPS FOR THE END OF FEBRUARY AND INTO MARCH WILL BE DOMINATED BY
COLD ARCTIC AIR WITH WELL BELOW NORMAL READINGS. WEDNESDAY LOOKS
TO BE THE ONLY DAY WE MAY BE WITHIN 10 DEGREES OF NORMAL FOR
HIGHS INTO THE NEXT WEEKEND. ALSO WILL SEE AN ACTIVE PERIOD WITH
SEVERAL CHANCES FOR SNOW THROUGHOUT THE WEEK AND INTO THE
WEEKEND.
TUESDAY WILL SEE ANOTHER DISTURBANCE DRIFTING ACROSS THE SW
PORTIONS OF THE CWA. BATTLE WILL BE BETWEEN RADIATION OF A HIGHER
LATE FEBRUARY SUN ANGLE AND SNOWFALL RATES...ON TOP OF A SNOW
PACK. PLOWED ROADS TODAY FOR THE MOST PART BECAME WET AND IN SOME
AREAS EVEN PARTIALLY DRIED...DESPITE CLOUDY SKIES. THINK CLOUDS
WILL BE THICKER LIMITING SOLAR IMPACT...HOWEVER MODELS ARE ONLY
PRODUCING LIGHT SNOW. DAYTIME SNOW OF A HALF INCH TO 1.5 INCHES
FOR THE MOST PART WITH A 15 TO 1 RATIO...HIGHEST ACROSS THE
SOUTHEASTERN PAN HANDLE AND SW NEB.
BY TUESDAY NIGHT ARCTIC HIGH PRESSURE WILL BE DRIFTING OVERHEAD.
CENTER CROSSES OVER THE CWA BETWEEN 04Z AND 09Z. BY 12Z THE HIGH
WILL BE TO THE SE WITH SOUTHWESTERLY WINDS TO BE ON THE
INCREASING...ALONG WITH WAA. LOWS INITIALLY EXPECTED WITH THE
CENTER OF THE HIGH OVERHEAD...EARLY IN THE NIGHT...HOWEVER WITH
THE EXPECTED SNOW PACK...DECOUPLING WILL KEEP WINDS FROM MIXING TO
THE GROUND UNTIL SUNRISE OR LATER. THIS MAY ALLOW A COUPLE OF
DEGREES FURTHER OF A DROP AFTER CENTER PASSES. EITHER
WAY...EXPECT LOWS TO FALL TO A FEW DEGREES ON EITHER SIDE OF ZERO.
WITH THE WAA FOR WED...HIGHS WILL REBOUND ABOVE FREEZING. WARMEST
GUIDANCE IS INTO THE 40S...HOWEVER THINK SNOW PACK WILL HOLD HIGHS
IN THE 30S.
NEXT COLD FRONT ARRIVES FOR THURSDAY WITH TEMPS TO TAKE A
DOWNWARD TREND. A COUPLE OF REINFORCING COLD FRONT WILL CONTINUE
TO TAKE TEMPS LOWER INTO THE WEEKEND. THIS WILL BE COUPLED WITH
SEVERAL DISTURBANCE TO RIDE ACROSS THE HIGH PLAINS WITH SEVERAL
CHANCES FOR SNOW. SNOW IS NOT EXPECTED TO BE CONSTANT...HOWEVER
CHANCES FOR AT LEAST LIGHT SNOW IN ANY 12 HOURS PERIOD WILL
RESULT IN MANY PERIODS WITH SNOW IN THE FORECAST.
NORMAL HIGHS THIS TIME OF YEAR SHOULD BE INTO THE 40S WITH LOWS
IN THE TEENS. MODELS ARE IN GOOD AGREEMENT WITH HIGHS ONLY IN THE
10S AND 20S FROM FRIDAY THROUGH THE WEEKEND AS THE COLD AIR
BLANKETS MUCH OF THE CONUS. COLDEST GUIDANCE IS THE EC WITH MANY
LOCATIONS NOT WARMING ABOVE SINGLE DIGITS FOR THE WEEKEND. THIS
IS NEARLY 40 DEGREES BELOW NORMAL. SUN ANGLE CONTINUES TO
INCREASE...AND RECORD LOW MAXES ARE IN THE SINGLE DIGITS...SO DO
NOT WANT TO GO WITH THE RECORD COLD FROM THE EC YET...THUS
FORECAST IS FAVORING A SLIGHTLY WARMER GFS AT THIS TIME. HOWEVER
WILL CONTINUE TO KEEP AN EYE ON THIS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1153 AM CST MON FEB 24 2014
THE MAIN CONCERN OVER THE NEXT 24 HOURS IS THE PASSAGE OF A COLD
FRONT THROUGH WESTERN NEBRASKA. WINDS WILL RAPIDLY SWITCH TO
NORTHWEST AND INCREASE IN SPEED LATE THIS AFTERNOON. SNOW SHOWERS
MAY ACCOMPANY THE FRONT...ESPECIALLY ACROSS NORTHERN NEBRASKA
INCLUDING THE KVTN TERMINAL. CEILINGS SHOULD RAISE TO VFR OVERNIGHT
BEHIND THE FRONT AS WINDS STAY STRONG ENOUGH TO PREVENT FOG FORMATION.
STRATUS WILL WORK INTO SOUTHWEST NEBRASKA AGAIN TUESDAY
MORNING...BUT THE PRECIPITATION SHOULD HOLD OFF UNTIL AFTER 25/18Z.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...MASEK
AVIATION...SNIVELY/TAYLOR
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1131 AM CST MON FEB 24 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 300 AM CST MON FEB 24 2014
...CURRENTLY AS OF 09Z...
WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED RIDGING ALONG
THE U.S. WEST COAST NORTHWARD THROUGH ALASKA...WHILE TROUGHING
DOMINATED FROM THE NORTH POLE SOUTHWARD THROUGH MUCH OF CANADA AND
THE NORTHERN TIER OF THE U.S.. WITHIN THIS TROUGHING...THERE ARE 3
IMPORTANT SHORTWAVE TROUGHS OF NOTE FOR THE FORECAST...
1. OVER SOUTHERN SASKATCHEWAN INTO NORTHWEST MONTANA...EXPECTED
TO BRING THE SNOW LATE TODAY INTO TONIGHT. DPVA AND ISENTROPIC
LIFT AHEAD OF THIS SHORTWAVE HAS SUPPORTED LIGHT SNOW ACROSS MUCH
OF MONTANA SOUTHEAST INTO NEBRASKA.
2. ALONG THE NUNAVUT/NORTHWEST TERRITORIES BORDER IN CANADA...
EXPECTED TO BRING THE ARCTIC COLD SHOT TO THE AREA TUESDAY NIGHT.
IN ITS WAKE SURFACE TEMPERATURES RANGE FROM A BITTER 20 TO 30
BELOW ZERO.
3. RIGHT NEAR THE NORTH POLE...SPECIFICALLY 84 N / 130 W...EXPECTED
TO BRING THE ARCTIC AIR FOR THURSDAY INTO THE WEEKEND. IN ITS
WAKE... 925MB TEMPS RANGE FROM -28 TO -34C PER GFS ANALYSIS.
OVER THE FORECAST AREA...SKIES REMAIN CLEAR DUE TO PLENTY OF DRY AIR
AS SEEN ON THE 00Z MPX SOUNDING. SOME CIRRUS IS BEGINNING TO
ENCROACH FROM THE WEST...THOUGH. TEMPERATURES HAVE SLOWLY COOLED
THROUGH THE NIGHT RESULTING FROM A WESTERLY BREEZE...WITH READINGS
IN THE LOWER SINGLE DIGITS.
... FORECAST ...
MODELS ARE IN GOOD AGREEMENT MARCHING THE FIRST SHORTWAVE TROUGH
INTO THE EASTERN DAKOTAS BY 00Z...OVER THE FORECAST AREA BY 06Z AND
INTO LOWER MICHIGAN BY 12Z TUE. 275-280K ISENTROPIC LIFT PROGS
SUGGEST THAT TO GET THE SNOW OVER MONTANA AND NEBRASKA INTO THE
FORECAST AREA...WE HAVE TO WAIT FOR THE SHORTWAVE TROUGH TO ARRIVE.
THIS IS WHY MODELS SLOWED DOWN OVER THE PAST FEW DAYS OF BRINGING
SNOW TO THE AREA. THE BEST LIFT...ALBEIT WEAK...IS PROGGED OVER THE
SOUTHWESTERN HALF OF THE FORECAST AREA BETWEEN 01-06Z...THEN SHIFTS
TO FAR SOUTHWEST WI BETWEEN 06-09Z BEFORE EXITING. PRECIPITATION
CHANCES HAVE BEEN ADJUSTED TO FIT THE TIMING OF THE LIFT SIGNAL.
STILL DOES NOT LOOK LIKE THERE WILL BE MUCH SNOW GIVEN THE WEAK
NATURE OF THE LIFT...PRECIPITABLE WATER ONLY 0.1-0.2 OF AN
INCH...AND THE SNOW RUNNING INTO THE DRY AIRMASS CURRENTLY IN PLACE.
ANY LIFT TOO IS MOSTLY ABOVE THE DENDRITIC GROWTH ZONE. PREVIOUS
FORECAST AMOUNTS OF LESS THAN 1 INCH SEEM REASONABLE.
REGARDING TEMPERATURES. 925MB READINGS AT 18Z TODAY ARE SIMILAR TO
YESTERDAY AT 18Z...BETWEEN -13 AND -16C. ONLY DIFFERENCES BETWEEN
TODAY AND YESTERDAY IS MORE CLOUD COVER AND STARTING OFF COLDER...
WHICH SHOULD KEEP HIGHS A LITTLE COOLER. IN THE WAKE OF THE
SHORTWAVE TROUGH PASSAGE TONIGHT...925MB TEMPS COOL TO -14 TO -19C.
A NORTHWEST BREEZE COMBINED WITH CLOUDS SHOULD HELP TO HOLD LOWS UP
SOMEWHAT...BUT READINGS SHOULD FALL INTO THE SINGLE DIGITS ABOVE AND
BELOW ZERO THROUGH ADVECTION...COLDEST OVER THE NORTHWEST HALF OF
THE FORECAST AREA.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 300 AM CST MON FEB 24 2014
THE BIG IMPACT STORY HERE IS THE COLD...
SHORTWAVE TROUGH CURRENTLY OVER THE NUNAVUT/NORTHWEST TERRITORIES
REGION IS PROGGED TO DROP THROUGH THE FORECAST AREA LATE
TUESDAY...USHERING IN THE FIRST SURGE OF BITTER COLD ARCTIC AIR.
TROUGH SHOULD GO THROUGH PRECIP FREE WITH JUST SOME CLOUDS. 925MB
TEMPS PLUMMET TO -21 TO -24C BY 06Z WEDNESDAY...SENDING SURFACE
TEMPERATURES DOWN BELOW ZERO. WITH THE COLD AIR FIRMLY ENTRENCHED
FOR 06-12Z...TEMPERATURES SHOULD IN MOST LOCATIONS DIP INTO TEENS
BELOW ZERO. MOS GUIDANCE WIND FORECASTS SUGGEST THE TYPICAL COLD
SPOTS COULD DECOUPLE...THUS HAVE THEM APPROACHING 20 BELOW. A WIND
CHILL ADVISORY IS A GIVEN FOR TUESDAY NIGHT INTO WEDNESDAY MORNING.
A BRIEF BREAK IN THE COLD AIR COMES WEDNESDAY AFTERNOON AS WESTERLY
WINDS INCREASE AND PULL IN SOME DOWNSLOPED AIR OFF THE ROCKIES. THIS
INCREASE IS A RESULT OF THE NEXT SHORTWAVE TROUGH NEAR THE NORTH
POLE DROPPING INTO THE MN ARROWHEAD. 925MB WINDS APPROACH 45-50 KT
AT 00Z THURSDAY WEST OF THE MISSISSIPPI RIVER...BRINGING UP CONCERN
OF A POSSIBLE WIND ADVISORY. HOWEVER...A STRONG INVERSION LOOKS TO
DEVELOP TO PRECLUDE MIXING THOSE HIGHER WINDS DOWN. IT STILL WILL BE
BRISK...THOUGH...AND STRONG ENOUGH TO RESULT IN SOME BLOWING AND
DRIFTING OF SNOW IN OPEN AREAS.
NEXT ARCTIC COLD SHOT WHICH IS MUCH MORE IMPRESSIVE COMES IN LATE
WEDNESDAY NIGHT. THE AFOREMENTIONED NORTH POLE SHORTWAVE CROSSES
UPPER MICHIGAN WEDNESDAY NIGHT...DRAGGING AN ARCTIC COLD FRONT
THROUGH THE FORECAST AREA. A STRONG PRESSURE RISE IS PROGGED BEHIND
THIS FRONT WHICH SHOULD RESULT IN A PERIOD OF BRISK NORTHWEST WINDS.
THEN 925MB TEMPS PLUMMET TO -23 TO -27C AT 12Z THURSDAY. DID NOT GO
AS COLD AS THESE WOULD SUGGEST GIVEN THE LATE ARRIVAL OF THE COLD
AIR AND PLENTY OF WIND. STILL...THE WIND CHILLS ARE PLENTY LOW
ENOUGH FOR AN ADVISORY.
THURSDAY AND THURSDAY NIGHT LOOK DOWNRIGHT COLD. 850MB TEMP
ANOMALIES ARE PROGGED BETWEEN 2.5-3 STANDARD DEVIATIONS BELOW
NORMAL...SUGGESTING RECORD TERRITORY. IN ADDITION...HIGH PRESSURE
SETTLES OVERHEAD THURSDAY NIGHT...SETTING UP POTENTIAL FOR
TEMPERATURES TO TANK. ONLY CAVEAT WILL BE SOME INCREASING MID/HIGH
CLOUDS LATER THURSDAY NIGHT. SOME WISCONSIN COLD SPOTS COULD DIP TO
30 BELOW OR COLDER...AS INDICATED BY THE MEX GUIDANCE.
FOR FRIDAY THROUGH MONDAY...THE FORECAST AREA WILL BE IN-BETWEEN
ARCTIC COLD UPPER TROUGHING ENCOMPASSING MUCH OF SOUTHERN CANADA AND
SHORTWAVE TROUGHS TRAVERSING THE SOUTHERN 2/3 OF THE U.S.. AT THE
SAME TIME AT THE SURFACE...ARCTIC HIGH PRESSURE SHOULD BE IN PLACE
FOR MUCH OF THE TIME. ONE SHORTWAVE MAY BRING SOME LIGHT SNOW TO
LOCATIONS SOUTH OF I-90 ON FRIDAY...IF IT CAN MAKE IT THROUGH THE
DRY AIR. ONLY KEPT 20 PERCENT CHANCES IN FOR THIS TIME PERIOD. SAME
HOLDS TRUE FOR ANOTHER SHORTWAVE TROUGH GOING BY SATURDAY NIGHT INTO
SUNDAY...THOUGH THE TRACK IS A BIT FARTHER NORTH SO CHANCES ARE A
LITTLE HIGHER. TEMPERATURES WILL STAY WELL BELOW NORMAL BEING UNDER
THE INFLUENCE OF THE ARCTIC SURFACE HIGH...THOUGH SOME GRADUAL
MODERATION SHOULD TAKE PLACE AS THE EARLY MARCH SUN WORKS ON THE
AIR. MORE WIND CHILL ADVISORIES ARE LIKELY...THOUGH...ESPECIALLY
FRIDAY NIGHT INTO SATURDAY MORNING.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1131 AM CST MON FEB 24 2014
WEATHER SYSTEM TO TRACK SOUTHWEST OF THE TAF SITES THIS
EVENING...AND WILL LIKELY SPREAD LIGHT SNOW ACROSS KRST/KLSE AS IT
PASSES. TIMING WISE...LOOK FOR THE HEART OF THE FALLING SNOW TO BE
CENTERED AROUND 03Z...AND SHOULD ONLY LAST 2-4 HOURS AT EITHER
LOCATION. IFR VISIBILITIES EXPECTED AT KRST...WHERE THE BETTER
FORCING AND SATURATION WILL EXIST. AT KLSE...SIGNIFICANT AMOUNT OF
DRY AIR IN PLACE COUPLED WITH WEAKER FORCING SHOULD LIMIT
RESTRICTIONS. CEILINGS LIKELY TO REMAIN AT OR ABOVE 2000 FT
THROUGH THE PERIOD. ONCE THE SYSTEM DEPARTS OVERNIGHT...LINGERING
MOISTURE TRAPPED UNDER A LOW LEVEL INVERSION WILL KEEP CLOUDS IN
PLACE THROUGH 12Z. FINALLY...PUSH OF DRIER TUESDAY MORNING WILL
SCATTER REMAINING CLOUDS OUT AND MIXING UP TO 925 MB SHOULD MAKE
FOR SOME LATE MORNING / AFTERNOON GUSTS UP TO 20-22 KTS AT KRST.
&&
.CLIMATE...
ISSUED AT 300 AM CST MON FEB 24 2014
GIVEN ALL THE COLD AIR TO ROUND OUT THE MONTH OF FEBRUARY...HERE IS
HOW FEBRUARY AND THE WINTER OVERALL WOULD STACK UP COMPARED TO
RECORDS BASED ON THE CURRENT FORECAST...
...FOR THE MONTH OF FEBRUARY...
LA CROSSE... 9.3 AVERAGE TEMPERATURE...3RD COLDEST
COLDER FEBRUARYS...
1873... 3.9
1936... 4.3
ROCHESTER... 6.7 AVERAGE TEMPERATURE...4TH COLDEST
COLDER FEBRUARYS...
1936... 0.5
1979... 5.7
1917... 6.0
...FOR THE WINTER...DECEMBER THROUGH FEBRUARY...
LA CROSSE... 11.5 AVERAGE TEMPERATURE...5TH COLDEST
COLDER WINTERS...
1872-1873... 8.4
1874-1875... 10.5
1977-1978... 11.4
1935-1936... 11.4
ROCHESTER... 8.8 AVERAGE TEMPERATURE...5TH COLDEST
COLDER WINTERS...
1978-1979... 5.6
1886-1887... 5.9
1935-1936... 8.1
1977-1978... 8.7
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM....AJ
AVIATION...ZT
CLIMATE......AJ/RRS