Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 02/23/14
SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NWS LOS ANGELES/OXNARD CA
937 AM PST FRI FEB 21 2014
...UPDATED AVIATION SECTION...
.SYNOPSIS...
HIGH PRESSURE WILL BRING MOSTLY CLEAR SKIES AND ABOVE NORMAL MAXIMUM
TEMPERATURES THROUGH SATURDAY. THE MARINE LAYER WILL RETURN SUNDAY
AND BRING COOLER TEMPERATURES INTO EARLY NEXT WEEK. IT IS GROWING
MORE AND MORE LIKELY THAT IT WILL BE WET FROM MID WEEK ON.
&&
.SHORT TERM (TODAY-MON)...A DENSE FOG FIELD DEVELOPED OVER THE SAN
PEDRO CHANNEL THIS MORNING AND WAS EXPANDING OVER THE CHANNEL WHILE
SURGING NORTH OVER THE SANTA MONICA BASIN AT THIS TIME. THE LOW
LEVEL PROFILER IS INOP AT LAX THIS MORNING AND ESTIMATE THE TOPS
USING THE ABC LONG BEACH WEB CAM AT 500 FEET OR LESS. HRRR INDICATED
LIGHT SOUTH WINDS OVER THE SANTA MONICA BASIN THROUGH EARLY
AFTERNOON AND THE DENSE FOG MAY CONTINUE NORTH AND SURGE ONTO THE
MALIBU COAST LATE THIS MORNING. HAVE ISSUED AN UPDATE FOR THE LOS
ANGELES COUNTY COAST AND SANTA CATALINA ISLAND OTHERWISE NO CHANGES.
THE FOLLOWING DISCUSSION IS FROM THE PREVIOUS SHIFT...
A COUPLE OF NICE DAYS ON TAP TODAY AND SATURDAY AS THE AREA SITS
UNDER MOSTLY CLEAR SKIES. DRY SW FLOW WILL BE OVERHEAD AS A RIDGE
WILL SIT TO THE WEST OF THE STATE. GOOD OFFSHORE FLOW THIS MORNING
(WITH SOME RESULTANT SUB ADVISORY 15 TO 25 MPH WINDS THROUGH AND
BELOW THE CANYONS) WILL MAKE TODAY THE WARMEST WITH MANY VLY MAX
TEMPS IN THE LOW TO MID 80S. ON SATURDAY ONSHORE TRENDS COULD BRING
SOME LOW CLOUDS TO THE LONG BEACH AREA IN THE MORNING AND WILL COOL
THE COASTS BUT THE INTERIOR TEMPS WILL BE PRETTY UNCHANGED.
STRONGER ONSHORE FLOW ON SUNDAY AND A WEAK EDDY WILL BRING LOW
CLOUDS TO LA/VTA/SRN SBA COASTS AND LOCALLY INTO THE COASTAL VLYS.
THIS WILL CAUSE A GOOD COOL DOWN FOR THE COASTS AND VLY. THE MTNS
AND INTERIOR SECTIONS WILL NOT SEE MUCH CHANGE IN TEMPS.
MONDAY WILL BE A NEAR CARBON COPY (NOTHING LIKE AN OUT OF DATE
REFERENCE) OF SUNDAY. MORNING LOW CLOUDS FOR THE COASTS AND VLYS
SOUTH OF POINT CONCEPTION...OTHERWISE MOSTLY CLEAR SKIES WITH NEAR
NORMAL MAX TEMPS.
.LONG TERM (TUE-THU)...
THE XTND FCST IS WHERE ALL THE ACTION IS. ON TUESDAY THE RIDGE MOVES
EASTWARD. ONSHORE FLOW INCREASES. MID AND HIGH LEVEL CLOUDS WILL
STREAM IN AND BLANKET THE AREAS. A DEEP MARINE LAYER SHOULD BE LIFT
UP ACROSS THE CSTS AND INTO THE VLYS AS WELL. SO LOOK FOR A CLOUDIER
COOLER DAY.
CONTINUED CLOUDY ON WEDNESDAY WITH A BIG MIX OF LOW MID AND HIGH
CLOUDS. BY THE AFTERNOON A FRONT WILL APPROACH THE AREA. TIMING IS
NOT A SURE THING AS THE FRONT AND TROF WILL HAVE TO FIGHT THE
DEPARTING RIDGE AND MAY WELL BE SLOWED DOWN. THE CANADIAN MDL IS THE
FASTEST THE EC JUST A TOUCH SLOWER AND THE GFS IS NOTICEABLY SLOWER.
ALL THREE MDLS BRING RAIN TO THE CENTRAL COAST WED EVENING SO LIKELY
POPS SEEM JUSTIFIED EVEN THOUGH ITS STILL ALONG WAYS AWAY. A CHANCE
OF RAIN ELSE WHERE AS THE FRONT MOVES THROUGH THE AREA OVERNIGHT AND
INTO THURSDAY MORNING. HGTS ARE PRETTY HIGH AND SNOW LEVELS SHOULD
STAY ABOVE 6500 FEET.
CURRENT MDLS RUNS SHOW A SMALL POP UP RIDGE FOR THURSDAY AND A MUCH
LESS CHANCE OF RAIN. THE RIDGE SHOULD BE VERY DIRTY FROM THE
VANGUARD OF CLOUDS STREAMING AHEAD OF THE NEXT BIGGER SYSTEM SO
SKIES WILL LIKELY BE MOSTLY CLOUDY. STILL KEEP SLGT CHC/CHC POPS
GOING FOR THE DAY BECAUSE THE MDLS CAN EASILY MISS THE FCST BY 12
HOURS AND THERE COULD BE LINGERING SHOWERS OR EARLY ARRIVING SHOWERS.
THE BIG NEWS CONTINUES TO BE NEXT FRIDAY AND SATURDAY WITH ALL MDLS
CONTINUING TO FCST A SUBSTANTIAL STORM. YOU WILL WANT TO STAY TUNED
FOR THE LATEST UPDATES FOR THIS STORM AS IT DEVELOPS.
&&
.AVIATION...21/1730Z
HIGH CONFIDENCE IN VFR CONDITIONS AT MOST SITES FOR THE NEXT 24
HOURS DUE TO WEAK OFFSHORE FLOW. SOME DENSE FOG AND STRATUS HAS
FORMED ALONG THE LA COAST THIS MORNING...BUT NOT EXPECTING IT TO
REACH LAX OR LGB TODAY. THERE IS A 40 PERCENT CHANCE THAT LGB WILL
HAVE IFR CIGS OR LOWER SATURDAY MORNING.
KLAX...HIGH CONFIDENCE IN VFR CONDITIONS THROUGH ABOUT 11Z SATURDAY
MORNING. 20 PERCENT CHANCE OF IFR OR LOWER CIGS AFTER 12Z.
KBUR...HIGH CONFIDENCE IN VFR CONDITIONS FOR THE NEXT 24 HOURS.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY (SEE LAXMWWLOX).
&&
$$
PUBLIC...30/RORKE
AVIATION...SUKUP
SYNOPSIS...SETO
WWW.WEATHER.GOV/LOSANGELES
SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NWS LOS ANGELES/OXNARD CA
855 AM PST FRI FEB 21 2014
.SYNOPSIS...
HIGH PRESSURE WILL BRING MOSTLY CLEAR SKIES AND ABOVE NORMAL MAXIMUM
TEMPERATURES THROUGH SATURDAY. THE MARINE LAYER WILL RETURN SUNDAY
AND BRING COOLER TEMPERATURES INTO EARLY NEXT WEEK. IT IS GROWING
MORE AND MORE LIKELY THAT IT WILL BE WET FROM MID WEEK ON.
&&
.SHORT TERM (TODAY-MON)...A DENSE FOG FIELD DEVELOPED OVER THE SAN
PEDRO CHANNEL THIS MORNING AND WAS EXPANDING OVER THE CHANNEL WHILE
SURGING NORTH OVER THE SANTA MONICA BASIN AT THIS TIME. THE LOW
LEVEL PROFILER IS INOP AT LAX THIS MORNING AND ESTIMATE THE TOPS
USING THE ABC LONG BEACH WEB CAM AT 500 FEET OR LESS. HRRR INDICATED
LIGHT SOUTH WINDS OVER THE SANTA MONICA BASIN THROUGH EARLY
AFTERNOON AND THE DENSE FOG MAY CONTINUE NORTH AND SURGE ONTO THE
MALIBU COAST LATE THIS MORNING. HAVE ISSUED AN UPDATE FOR THE LOS
ANGELES COUNTY COAST AND SANTA CATALINA ISLAND OTHERWISE NO CHANGES.
THE FOLLOWING DISCUSSION IS FROM THE PREVIOUS SHIFT...
A COUPLE OF NICE DAYS ON TAP TODAY AND SATURDAY AS THE AREA SITS
UNDER MOSTLY CLEAR SKIES. DRY SW FLOW WILL BE OVERHEAD AS A RIDGE
WILL SIT TO THE WEST OF THE STATE. GOOD OFFSHORE FLOW THIS MORNING
(WITH SOME RESULTANT SUB ADVISORY 15 TO 25 MPH WINDS THROUGH AND
BELOW THE CANYONS) WILL MAKE TODAY THE WARMEST WITH MANY VLY MAX
TEMPS IN THE LOW TO MID 80S. ON SATURDAY ONSHORE TRENDS COULD BRING
SOME LOW CLOUDS TO THE LONG BEACH AREA IN THE MORNING AND WILL COOL
THE COASTS BUT THE INTERIOR TEMPS WILL BE PRETTY UNCHANGED.
STRONGER ONSHORE FLOW ON SUNDAY AND A WEAK EDDY WILL BRING LOW
CLOUDS TO LA/VTA/SRN SBA COASTS AND LOCALLY INTO THE COASTAL VLYS.
THIS WILL CAUSE A GOOD COOL DOWN FOR THE COASTS AND VLY. THE MTNS
AND INTERIOR SECTIONS WILL NOT SEE MUCH CHANGE IN TEMPS.
MONDAY WILL BE A NEAR CARBON COPY (NOTHING LIKE AN OUT OF DATE
REFERENCE) OF SUNDAY. MORNING LOW CLOUDS FOR THE COASTS AND VLYS
SOUTH OF POINT CONCEPTION...OTHERWISE MOSTLY CLEAR SKIES WITH NEAR
NORMAL MAX TEMPS.
.LONG TERM (TUE-THU)...
THE XTND FCST IS WHERE ALL THE ACTION IS. ON TUESDAY THE RIDGE MOVES
EASTWARD. ONSHORE FLOW INCREASES. MID AND HIGH LEVEL CLOUDS WILL
STREAM IN AND BLANKET THE AREAS. A DEEP MARINE LAYER SHOULD BE LIFT
UP ACROSS THE CSTS AND INTO THE VLYS AS WELL. SO LOOK FOR A CLOUDIER
COOLER DAY.
CONTINUED CLOUDY ON WEDNESDAY WITH A BIG MIX OF LOW MID AND HIGH
CLOUDS. BY THE AFTERNOON A FRONT WILL APPROACH THE AREA. TIMING IS
NOT A SURE THING AS THE FRONT AND TROF WILL HAVE TO FIGHT THE
DEPARTING RIDGE AND MAY WELL BE SLOWED DOWN. THE CANADIAN MDL IS THE
FASTEST THE EC JUST A TOUCH SLOWER AND THE GFS IS NOTICEABLY SLOWER.
ALL THREE MDLS BRING RAIN TO THE CENTRAL COAST WED EVENING SO LIKELY
POPS SEEM JUSTIFIED EVEN THOUGH ITS STILL ALONG WAYS AWAY. A CHANCE
OF RAIN ELSE WHERE AS THE FRONT MOVES THROUGH THE AREA OVERNIGHT AND
INTO THURSDAY MORNING. HGTS ARE PRETTY HIGH AND SNOW LEVELS SHOULD
STAY ABOVE 6500 FEET.
CURRENT MDLS RUNS SHOW A SMALL POP UP RIDGE FOR THURSDAY AND A MUCH
LESS CHANCE OF RAIN. THE RIDGE SHOULD BE VERY DIRTY FROM THE
VANGUARD OF CLOUDS STREAMING AHEAD OF THE NEXT BIGGER SYSTEM SO
SKIES WILL LIKELY BE MOSTLY CLOUDY. STILL KEEP SLGT CHC/CHC POPS
GOING FOR THE DAY BECAUSE THE MDLS CAN EASILY MISS THE FCST BY 12
HOURS AND THERE COULD BE LINGERING SHOWERS OR EARLY ARRIVING SHOWERS.
THE BIG NEWS CONTINUES TO BE NEXT FRIDAY AND SATURDAY WITH ALL MDLS
CONTINUING TO FCST A SUBSTANTIAL STORM. YOU WILL WANT TO STAY TUNED
FOR THE LATEST UPDATES FOR THIS STORM AS IT DEVELOPS.
&&
.AVIATION...
21/1200Z
HI CONFIDENCE IN THE 12Z TAFS WITH VFR CONDITIONS EXPECTED AT ALL
THE AIRFIELDS FOR AT LEAST THE NEXT 18 HOURS. MARINE STRATUS COULD
DEVELOP OVER THE L.A. COAST AFTER 08Z SATURDAY.
KLAX...HI CONFIDENCE IN CAVU TAF THROUGH 08Z. THERE IS A 40 PERCENT
CHANCE OF LIFR CIGS AFTER 08Z.
KBUR...HI CONFIDENCE IN CAVU TAF.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY (SEE LAXMWWLOX).
&&
$$
PUBLIC...30/RORKE
AVIATION...KAPLAN
SYNOPSIS...SETO
WWW.WEATHER.GOV/LOSANGELES
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1005 AM MST FRI FEB 21 2014
.UPDATE...WINDS HAVE PICKED UP SOONER THAN EXPECTED AND HAVE
ALREADY UPDATED FOR THIS. ALSO LOWERED POPS AND SNOW AMOUNTS FOR
THE MOUNTAINS TODAY. WEB CAMERAS SHOWING THE SNOW IS CONFINED TO
THE HIGHER MOUNTAINS AND EXPECT THAT TREND TO CONTINUE THROUGH
TODAY. HIGHS LOOK ON TRACK...MAY NEED TO EVENTUALLY LOWER
TEMPERATURES A COUPLE OF DEGREES IF ANY ADJUSTMENTS ARE NEEDED.
&&
.AVIATION...STRONG WEST WINDS HAVE DEVELOPED AND WILL CONTINUE
UNTIL AROUND 00-01Z. GUSTS TO 40 TO 45 KNOTS WILL BE POSSIBLE AT
KDEN AND KAPA WITH GUSTS TO AROUND 50 KNOTS AT KBJC. WEST WINDS
WILL TURN SOUTHWEST DURING THE EVENING HOURS.
&&
.PREV DISCUSSION... /ISSUED 535 AM MST FRI FEB 21 2014/
UPDATE...
SHORT TERM...WINDS HAVE DROPPED OFF TO BLO WARNING LEVELS EVEN AT
THE NORMAL WINDY SPOTS SO WILL CANCEL THE HI WIND WARNING EARLY.
PREV DISCUSSION... /ISSUED 344 AM MST FRI FEB 21 2014/
SHORT TERM...NW FLOW ALOFT WILL REMAIN OVER THE AREA TODAY THRU
TONIGHT. DECENT WIND EVENT OCCURRED LATE LAST EVENING INTO THE
EARLY MORNING HOURS IN AND NEAR THE FOOTHILLS OF BOULDER AND
JEFFERSON COUNTIES AS GUSTS RANGED FROM 70-90 MPH. THE LAST FEW
HOURS WINDS HAVE DECREASED WITH GUSTS MAINLY IN THE 50-60 MPH
RANGE WITH A FEW GUSTS TO 70 MPH AT TIMES. OVERALL MTN WAVE SHOULD
BREAKDOWN BY 12Z WITH THREAT OF HIGH WINDS GRADUALLY BY 9 AM IF
NOT SOONER. HOWEVER IT STILL WILL BE VERY WINDY AT TIMES THROUGH
MIDDAY.
IN THE MTNS MOISTURE WAS INCREASING EARLY THIS MORNING AND COMBINED
WITH FAVORABLE OROGRAPHICS WAS PRODUCING SNOW IN THE MTNS WITH
AREAS OF BLOWING SNOW OVER THE HIGHER PASSES. MOISTURE IS FCST TO
DECREASE BY MIDDAY THRU THE EARLY EVENING HOURS SO SNOW COVERAGE
WILL LIKELY DECREASE BY 18Z ALTHOUGH AREAS OF BLOWING SNOW WILL
STILL BE POSSIBLE.
ACROSS NERN CO WITH RATHER STG NWLY FLOW IN THE LOWER LEVELS AS
MIXING OCCURS LATER THIS MORNING THRU THE AFTN HOURS WILL SEE
GUSTY NORTHWEST WINDS WITH SOME GUSTS IN THE 40-50 MPH RANGE AT
TIMES. AS FOR HIGHS WILL KEEP READINGS IN THE 45 TO 50 DEGREE
RANGE OVER THE PLAINS.
FOR TONIGHT MOISTURE MAY INCREASE IN THE MTNS AFTER MIDNIGHT WITH
BETTER COVERAGE OF SNOW ESPECIALLY NORTH OF I-70. WINDS WILL REMAIN
GUSTY IN THE MTNS AND FOOTHILLS HOWEVER CROSS MTN FLOW IS ONLY IN
THE 45-50 KT RANGE OVERNIGHT WITH A WEAKER MTN WAVE AS COMPARED
TO LAST NIGHT. THUS POTENTIAL FOR HIGH WINDS LOOKS ON THE LOW SIDE AT
THIS POINT HOWEVER STILL MAY SEE A FEW GUSTS TO 60-70 MPH AT TIMES
IN A FEW LOCATIONS.
LONG TERM...STRONG WESTERLY JET LEVEL FLOW IS PROGGED TO
CONTINUE OVER THE CWA SATURDAY INTO SUNDAY MORNING. FOR THE REST
TO SUNDAY AND SUNDAY NIGHT...THE FLOW ALOFT DECREASES A BIT AND IS
WEST-NORTHWESTERLY. THERE IS QG ASCENT PROGGED FOR THE CWA
SATURDAY INTO THE EARLY EVENING...THEN DOWNWARD MOTION IS PROGGED
WELL INTO SUNDAY. THERE IS WEAK UPWARD TO NEUTRAL SYNOPTIC SCALE
ENERGY FOR SUNDAY NIGHT. THE LOW LEVEL PRESSURE AND WIND FIELDS
POINT TO NORMAL DIURNAL PATTERNS FOR WINDS SATURDAY. MODELS DO
NOT BRING THE COLD FRONT INTO THE CWA UNTIL LATE AFTERNOON/EARLY
EVENING. UPSLOPE IS PROGGED ALL OF SATURDAY NIGHT...WITH
SOUTHEASTERLIES ON SUNDAY. TROUGHING IS PROGGED TO DEVELOP EAST OF
THE MOUNTAINS SUNDAY NIGHT...AND ENHANCED DRAINAGE WIND PATTERNS
CAN BE EXPECTED FOR THE PLAINS AND FOOTHILLS. FOR MOISTURE...
THERE IS SOME OVER THE MOUNTAINS ON SATURDAY...AND LITTLE OVER THE
PLAINS. IT IS A BIT DEEPER OVER THE MOUNTAINS SATURDAY NIGHT...
WITH A BIT AT THE LOWER LEVELS FOR THE PLAINS. THERE IS SOME
MOISTURE HANGING AROUND OVER THE MOUNTAINS SUNDAY AND SUNDAY
NIGHT...WITH A BIT OVER THE PLAINS IN THE MORNING ONLY. OVERALL
.MOISTURE IS LESS ON THESE 00Z MODEL RUNS COMPARED TO
YESTERDAY`S. THE QPF FIELDS HAVE SMALL AMOUNTS OF MEASURABLE
SNOWFALL OVER THE MOUNTAINS SATURDAY THROUGH ABOUT MID DAY SUNDAY.
THERE IS A TAD OVER THE PLAINS...MOSTLY THE NORTHERN HALF...
SATURDAY AFTERNOON LATE INTO SUNDAY MORNING. FOR POPS WILL GO WITH
40-70%S IN THE MOUNTAINS SATURDAY AND SATURDAY NIGHT. WILL GO WITH
"CHANCE"S OVER THE NORTHERN HALF OF THE PLAINS SATURDAY NIGHT.
WINDS SHOULD BE BE PARTICULARLY STRONG. THERE WILL BE SOME
DECREASING POPS OVER THE MOUNTAINS AND NORTHEAST CORNER ON SUNDAY.
SUNDAY NIGHT SHOULD BE DRY. FOR TEMPERATURES...SATURDAY`S HIGHS
SHOULD ONLY BE A TAD COLDER THAN TODAY`S...ESPECIALLY SINCE THE
COLD FRONT IS PROGGED IN LATE DAY. SUNDAY`S HIGHS ARE 1-3 C COLDER
THAN SATURDAY`S. FOR THE LATER DAYS...MONDAY THROUGH THURSDAY...
WEAKER WEST-NORTHWESTERLY FLOW IS PROGGED MONDAY INTO TUESDAY. A
WEAK UPPER TROUGH SLIDES IN FROM THE NORTHWEST LATER TUESDAY AND
TUESDAY NIGHT WITH AN ASSOCIATED COLD FRONT. TUESDAY LOOKS TO HAVE
BETTER POPS FOR ALL THE CWA THAN PREVIOUS MODELS INDICATED. THE
WEST-NORTHWESTERLY FLOW ALOFT CONTINUES ON WEDNESDAY AND
THURSDAY. THERE IS AN UPPER RIDGE AXIS JUST WEST OF THE CWA ON
THURSDAY.
AVIATION...WNW WINDS WERE ALREADY OCCURRING AT DIA WITH GUSTS
TO 25 MPH AT TIMES EARLY THIS MORNING. BOTH THE HRRR AND RAP SHOW
GUSTY WNW WINDS THRU 00Z WITH SOME GUSTS TO 40 MPH AT TIMES.
AFTER 00Z WINDS MAY BECOME MORE WLY WITH SPEEDS IN THE 10-20 MPH
RANGE WHICH WILL GRADUALLY BECOME MORE SSW AFTER 03Z. OTHERWISE
EXPECT VFR CONDITIONS TODAY THRU TONIGHT.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...RPK
LONG TERM....RJK
UPDATE/AVIATION...MEIER
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
535 AM MST FRI FEB 21 2014
.UPDATE...
&&
.SHORT TERM...WINDS HAVE DROPPED OFF TO BLO WARNING LEVELS EVEN AT
THE NORMAL WINDY SPOTS SO WILL CANCEL THE HI WIND WARNING EARLY.
.PREV DISCUSSION... /ISSUED 344 AM MST FRI FEB 21 2014/
SHORT TERM...NW FLOW ALOFT WILL REMAIN OVER THE AREA TODAY THRU
TONIGHT. DECENT WIND EVENT OCCURRED LATE LAST EVENING INTO THE
EARLY MORNING HOURS IN AND NEAR THE FOOTHILLS OF BOULDER AND
JEFFERSON COUNTIES AS GUSTS RANGED FROM 70-90 MPH. THE LAST FEW
HOURS WINDS HAVE DECREASED WITH GUSTS MAINLY IN THE 50-60 MPH
RANGE WITH A FEW GUSTS TO 70 MPH AT TIMES. OVERALL MTN WAVE SHOULD
BREAKDOWN BY 12Z WITH THREAT OF HIGH WINDS GRADUALLY BY 9 AM IF
NOT SOONER. HOWEVER IT STILL WILL BE VERY WINDY AT TIMES THROUGH
MIDDAY.
IN THE MTNS MOISTURE WAS INCREASING EARLY THIS MORNING AND COMBINED
WITH FAVORABLE OROGRAPHICS WAS PRODUCING SNOW IN THE MTNS WITH
AREAS OF BLOWING SNOW OVER THE HIGHER PASSES. MOISTURE IS FCST TO
DECREASE BY MIDDAY THRU THE EARLY EVENING HOURS SO SNOW COVERAGE
WILL LIKELY DECREASE BY 18Z ALTHOUGH AREAS OF BLOWING SNOW WILL
STILL BE POSSIBLE.
ACROSS NERN CO WITH RATHER STG NWLY FLOW IN THE LOWER LEVELS AS
MIXING OCCURS LATER THIS MORNING THRU THE AFTN HOURS WILL SEE
GUSTY NORTHWEST WINDS WITH SOME GUSTS IN THE 40-50 MPH RANGE AT
TIMES. AS FOR HIGHS WILL KEEP READINGS IN THE 45 TO 50 DEGREE
RANGE OVER THE PLAINS.
FOR TONIGHT MOISTURE MAY INCREASE IN THE MTNS AFTER MIDNIGHT WITH
BETTER COVERAGE OF SNOW ESPECIALLY NORTH OF I-70. WINDS WILL REMAIN
GUSTY IN THE MTNS AND FOOTHILLS HOWEVER CROSS MTN FLOW IS ONLY IN
THE 45-50 KT RANGE OVERNIGHT WITH A WEAKER MTN WAVE AS COMPARED
TO LAST NIGHT. THUS POTENTIAL FOR HIGH WINDS LOOKS ON THE LOW SIDE AT
THIS POINT HOWEVER STILL MAY SEE A FEW GUSTS TO 60-70 MPH AT TIMES
IN A FEW LOCATIONS.
LONG TERM...STRONG WESTERLY JET LEVEL FLOW IS PROGGED TO
CONTINUE OVER THE CWA SATURDAY INTO SUNDAY MORNING. FOR THE REST
TO SUNDAY AND SUNDAY NIGHT...THE FLOW ALOFT DECREASES A BIT AND IS
WEST-NORTHWESTERLY. THERE IS QG ASCENT PROGGED FOR THE CWA
SATURDAY INTO THE EARLY EVENING...THEN DOWNWARD MOTION IS PROGGED
WELL INTO SUNDAY. THERE IS WEAK UPWARD TO NEUTRAL SYNOPTIC SCALE
ENERGY FOR SUNDAY NIGHT. THE LOW LEVEL PRESSURE AND WIND FIELDS
POINT TO NORMAL DIURNAL PATTERNS FOR WINDS SATURDAY. MODELS DO
NOT BRING THE COLD FRONT INTO THE CWA UNTIL LATE AFTERNOON/EARLY
EVENING. UPSLOPE IS PROGGED ALL OF SATURDAY NIGHT...WITH
SOUTHEASTERLIES ON SUNDAY. TROUGHING IS PROGGED TO DEVELOP EAST OF
THE MOUNTAINS SUNDAY NIGHT...AND ENHANCED DRAINAGE WIND PATTERNS
CAN BE EXPECTED FOR THE PLAINS AND FOOTHILLS. FOR MOISTURE...
THERE IS SOME OVER THE MOUNTAINS ON SATURDAY...AND LITTLE OVER THE
PLAINS. IT IS A BIT DEEPER OVER THE MOUNTAINS SATURDAY NIGHT...
WITH A BIT AT THE LOWER LEVELS FOR THE PLAINS. THERE IS SOME
MOISTURE HANGING AROUND OVER THE MOUNTAINS SUNDAY AND SUNDAY
NIGHT...WITH A BIT OVER THE PLAINS IN THE MORNING ONLY. OVERALL
..MOISTURE IS LESS ON THESE 00Z MODEL RUNS COMPARED TO
YESTERDAY`S. THE QPF FIELDS HAVE SMALL AMOUNTS OF MEASURABLE
SNOWFALL OVER THE MOUNTAINS SATURDAY THROUGH ABOUT MID DAY SUNDAY.
THERE IS A TAD OVER THE PLAINS...MOSTLY THE NORTHERN HALF...
SATURDAY AFTERNOON LATE INTO SUNDAY MORNING. FOR POPS WILL GO WITH
40-70%S IN THE MOUNTAINS SATURDAY AND SATURDAY NIGHT. WILL GO WITH
"CHANCE"S OVER THE NORTHERN HALF OF THE PLAINS SATURDAY NIGHT.
WINDS SHOULD BE BE PARTICULARLY STRONG. THERE WILL BE SOME
DECREASING POPS OVER THE MOUNTAINS AND NORTHEAST CORNER ON SUNDAY.
SUNDAY NIGHT SHOULD BE DRY. FOR TEMPERATURES...SATURDAY`S HIGHS
SHOULD ONLY BE A TAD COLDER THAN TODAY`S...ESPECIALLY SINCE THE
COLD FRONT IS PROGGED IN LATE DAY. SUNDAY`S HIGHS ARE 1-3 C COLDER
THAN SATURDAY`S. FOR THE LATER DAYS...MONDAY THROUGH THURSDAY...
WEAKER WEST-NORTHWESTERLY FLOW IS PROGGED MONDAY INTO TUESDAY. A
WEAK UPPER TROUGH SLIDES IN FROM THE NORTHWEST LATER TUESDAY AND
TUESDAY NIGHT WITH AN ASSOCIATED COLD FRONT. TUESDAY LOOKS TO HAVE
BETTER POPS FOR ALL THE CWA THAN PREVIOUS MODELS INDICATED. THE
WEST-NORTHWESTERLY FLOW ALOFT CONTINUES ON WEDNESDAY AND
THURSDAY. THERE IS AN UPPER RIDGE AXIS JUST WEST OF THE CWA ON
THURSDAY.
&&
.AVIATION...WNW WINDS WERE ALREADY OCCURRING AT DIA WITH GUSTS
TO 25 MPH AT TIMES EARLY THIS MORNING. BOTH THE HRRR AND RAP SHOW
GUSTY WNW WINDS THRU 00Z WITH SOME GUSTS TO 40 MPH AT TIMES.
AFTER 00Z WINDS MAY BECOME MORE WLY WITH SPEEDS IN THE 10-20 MPH
RANGE WHICH WILL GRADUALLY BECOME MORE SSW AFTER 03Z. OTHERWISE
EXPECT VFR CONDITIONS TODAY THRU TONIGHT.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...RPK
LONG TERM....RJK
AVIATION...RPK
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
344 AM MST FRI FEB 21 2014
.SHORT TERM...NW FLOW ALOFT WILL REMAIN OVER THE AREA TODAY THRU
TONIGHT. DECENT WIND EVENT OCCURRED LATE LAST EVENING INTO THE
EARLY MORNING HOURS IN AND NEAR THE FOOTHILLS OF BOULDER AND
JEFFERSON COUNTIES AS GUSTS RANGED FROM 70-90 MPH. THE LAST FEW
HOURS WINDS HAVE DECREASED WITH GUSTS MAINLY IN THE 50-60 MPH
RANGE WITH A FEW GUSTS TO 70 MPH AT TIMES. OVERALL MTN WAVE SHOULD
BREAKDOWN BY 12Z WITH THREAT OF HIGH WINDS GRADUALLY BY 9 AM IF
NOT SOONER. HOWEVER IT STILL WILL BE VERY WINDY AT TIMES THROUGH
MIDDAY.
IN THE MTNS MOISTURE WAS INCREASING EARLY THIS MORNING AND COMBINED
WITH FAVORABLE OROGRAPHICS WAS PRODUCING SNOW IN THE MTNS WITH
AREAS OF BLOWING SNOW OVER THE HIGHER PASSES. MOISTURE IS FCST TO
DECREASE BY MIDDAY THRU THE EARLY EVENING HOURS SO SNOW COVERAGE
WILL LIKELY DECREASE BY 18Z ALTHOUGH AREAS OF BLOWING SNOW WILL
STILL BE POSSIBLE.
ACROSS NERN CO WITH RATHER STG NWLY FLOW IN THE LOWER LEVELS AS
MIXING OCCURS LATER THIS MORNING THRU THE AFTN HOURS WILL SEE
GUSTY NORTHWEST WINDS WITH SOME GUSTS IN THE 40-50 MPH RANGE AT
TIMES. AS FOR HIGHS WILL KEEP READINGS IN THE 45 TO 50 DEGREE
RANGE OVER THE PLAINS.
FOR TONIGHT MOISTURE MAY INCREASE IN THE MTNS AFTER MIDNIGHT WITH
BETTER COVERAGE OF SNOW ESPECIALLY NORTH OF I-70. WINDS WILL REMAIN
GUSTY IN THE MTNS AND FOOTHILLS HOWEVER CROSS MTN FLOW IS ONLY IN
THE 45-50 KT RANGE OVERNIGHT WITH A WEAKER MTN WAVE AS COMPARED
TO LAST NIGHT. THUS POTENTIAL FOR HIGH WINDS LOOKS ON THE LOW SIDE AT
THIS POINT HOWEVER STILL MAY SEE A FEW GUSTS TO 60-70 MPH AT TIMES
IN A FEW LOCATIONS.
.LONG TERM...STRONG WESTERLY JET LEVEL FLOW IS PROGGED TO
CONTINUE OVER THE CWA SATURDAY INTO SUNDAY MORNING. FOR THE REST
TO SUNDAY AND SUNDAY NIGHT...THE FLOW ALOFT DECREASES A BIT AND IS
WEST-NORTHWESTERLY. THERE IS QG ASCENT PROGGED FOR THE CWA
SATURDAY INTO THE EARLY EVENING...THEN DOWNWARD MOTION IS PROGGED
WELL INTO SUNDAY. THERE IS WEAK UPWARD TO NEUTRAL SYNOPTIC SCALE
ENERGY FOR SUNDAY NIGHT. THE LOW LEVEL PRESSURE AND WIND FIELDS
POINT TO NORMAL DIURNAL PATTERNS FOR WINDS SATURDAY. MODELS DO
NOT BRING THE COLD FRONT INTO THE CWA UNTIL LATE AFTERNOON/EARLY
EVENING. UPSLOPE IS PROGGED ALL OF SATURDAY NIGHT...WITH
SOUTHEASTERLIES ON SUNDAY. TROUGHING IS PROGGED TO DEVELOP EAST OF
THE MOUNTAINS SUNDAY NIGHT...AND ENHANCED DRAINAGE WIND PATTERNS
CAN BE EXPECTED FOR THE PLAINS AND FOOTHILLS. FOR MOISTURE...
THERE IS SOME OVER THE MOUNTAINS ON SATURDAY...AND LITTLE OVER THE
PLAINS. IT IS A BIT DEEPER OVER THE MOUNTAINS SATURDAY NIGHT...
WITH A BIT AT THE LOWER LEVELS FOR THE PLAINS. THERE IS SOME
MOISTURE HANGING AROUND OVER THE MOUNTAINS SUNDAY AND SUNDAY
NIGHT...WITH A BIT OVER THE PLAINS IN THE MORNING ONLY. OVERALL
...MOISTURE IS LESS ON THESE 00Z MODEL RUNS COMPARED TO
YESTERDAY`S. THE QPF FIELDS HAVE SMALL AMOUNTS OF MEASURABLE
SNOWFALL OVER THE MOUNTAINS SATURDAY THROUGH ABOUT MID DAY SUNDAY.
THERE IS A TAD OVER THE PLAINS...MOSTLY THE NORTHERN HALF...
SATURDAY AFTERNOON LATE INTO SUNDAY MORNING. FOR POPS WILL GO WITH
40-70%S IN THE MOUNTAINS SATURDAY AND SATURDAY NIGHT. WILL GO WITH
"CHANCE"S OVER THE NORTHERN HALF OF THE PLAINS SATURDAY NIGHT.
WINDS SHOULD BE BE PARTICULARLY STRONG. THERE WILL BE SOME
DECREASING POPS OVER THE MOUNTAINS AND NORTHEAST CORNER ON SUNDAY.
SUNDAY NIGHT SHOULD BE DRY. FOR TEMPERATURES...SATURDAY`S HIGHS
SHOULD ONLY BE A TAD COLDER THAN TODAY`S...ESPECIALLY SINCE THE
COLD FRONT IS PROGGED IN LATE DAY. SUNDAY`S HIGHS ARE 1-3 C COLDER
THAN SATURDAY`S. FOR THE LATER DAYS...MONDAY THROUGH THURSDAY...
WEAKER WEST-NORTHWESTERLY FLOW IS PROGGED MONDAY INTO TUESDAY. A
WEAK UPPER TROUGH SLIDES IN FROM THE NORTHWEST LATER TUESDAY AND
TUESDAY NIGHT WITH AN ASSOCIATED COLD FRONT. TUESDAY LOOKS TO HAVE
BETTER POPS FOR ALL THE CWA THAN PREVIOUS MODELS INDICATED. THE
WEST-NORTHWESTERLY FLOW ALOFT CONTINUES ON WEDNESDAY AND
THURSDAY. THERE IS AN UPPER RIDGE AXIS JUST WEST OF THE CWA ON
THURSDAY.
&&
.AVIATION...WNW WINDS WERE ALREADY OCCURRING AT DIA WITH GUSTS
TO 25 MPH AT TIMES EARLY THIS MORNING. BOTH THE HRRR AND RAP SHOW
GUSTY WNW WINDS THRU 00Z WITH SOME GUSTS TO 40 MPH AT TIMES.
AFTER 00Z WINDS MAY BECOME MORE WLY WITH SPEEDS IN THE 10-20 MPH
RANGE WHICH WILL GRADUALLY BECOME MORE SSW AFTER 03Z. OTHERWISE
EXPECT VFR CONDITIONS TODAY THRU TONIGHT.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WARNING UNTIL 9 AM MST THIS MORNING FOR COZ033>036-038-
039.
&&
$$
SHORT TERM...RPK
LONG TERM....RJK
AVIATION...RPK
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
1117 PM MST THU FEB 20 2014
.UPDATE...
ISSUED AT 1115 PM MST THU FEB 20 2014
AFTER A LOOK AT THE 00Z GFS MODEL AND WHAT IS NOT HAPPENING ON
SATELLITE...WE HAVE CANCELLED THE WINTER WEATHER ADVISORIES OVER
THE NORTHERN COLORADO MTNS. THANKS TO PUB FOR COORDINATION.
UPDATE ISSUED AT 945 PM MST THU FEB 20 2014
SURFACE HIGH PRESSURE IS CENTERED OVER THE FOUR CORNERS AREA
TONIGHT BRINGING STRONGER INVERSIONS TO THE SOUTH AND THUS MUCH
COLDER TEMPERATURES THAN 24 HRS AGO. THE GRADIENT REMAINS TIGHT
ACROSS THE NORTH ESPECIALLY ALONG THE PARK/GORE RANGES. CLOUDS ARE
STRETCHED ALONG THE WYOMING BORDER AND ALONG THE CONTINENTAL
DIVIDE.
CONCERNING THE ADVISORIES IN THE NW COLORADO MTNS...THE 00Z NAM
PRODUCES ONLY VERY LIGHT SNOW ACROSS THE EASTERN MTNS TONIGHT AND
EVEN INTO FRIDAY. NAM AND RAP FORECAST SOUNDINGS SHOW THE PROFILE
BECOMING MUCH MORE STABLE IN MILD 700MB WARM ADVECTION BUT ALSO
THE PROFILE IS NOT FULLY SATURATING. THE PROFILE BECOMES MILDLY
UNSTABLE THROUGH A SHALLOW LAYER TO ABOUT 11KFT ON FRIDAY. ITS NOT
UNTIL AROUND SUNSET FRIDAY THAT A 100KT JET NOSES IN FROM THE NW
AND PRODUCES SOME ADDITIONAL FORCING THAT SNOW REALLY STARTS TO
ACCUMULATE. WILL LOOK CLOSELY AT THE NEW GFS AND THE CURRENT
HIGHLIGHTS TONIGHT.
ELSEWHERE AFTER A COLD START TO THE DAY EXPECT PERIODS OF CLOUDS
AND DAYTIME TEMPERATURES RECOVERING TO JUST BELOW NORMAL.
&&
.SHORT TERM...(TONIGHT THROUGH FRIDAY NIGHT)
ISSUED AT 344 PM MST THU FEB 20 2014
THE LAST STORM SYSTEM HAS MOVED ONTO THE PLAINS WHERE IT IS
PRODUCING SEVERE WEATHER THIS AFTERNOON. IN IT/S WAKE...COLDER
TEMPERATURES AND ISOLATED TO SCATTERED SHOWERS PERSIST ACROSS THE
DIVIDE MOUNTAINS. WINDS ALSO CONTINUE TO GUST OVER 35 MPH ALONG THE
SPINE OF THE ROCKIES AND THIS IS LIKELY TO CONTINUE OVER THE NEXT
FEW DAYS AS FAST NORTHWEST FLOW WAVERS OVER SOUTHERN WYOMING AND
NORTHERN COLORADO. THE INFUSION OF PACIFIC MOISTURE AND EMBEDDED
ENERGY WILL BRING WAVES OF SNOW TO THE REGION WITH THE NEXT BATCH
EXPECTED OVERNIGHT. 290-300K MOISTURE TRANSPORT VECTORS SHOW THIS
MOISTURE ARRIVING THROUGH THE EVENING ALONG WITH AN INCREASE IN JET
LEVEL WINDS. WAA INCREASES WITH THE APPROACH OF MID LEVEL ENERGY
AND THIS DEEPENS THE DENDRITIC LAYER UP NORTH AS THE LOWER PORTION
OF THE SOUNDING APPROACHES ISOTHERMAL. NEGATIVE EPV VALUES JUST
ABOVE THIS LAYER ALSO SUGGEST SOME POTENTIAL FOR BETTER SNOWFALL
PRODUCTION ACROSS THE NORTHERN MOUNTAINS THROUGH SUNRISE. THOUGH
MID LEVEL TEMPERATURES ARE WARMING...AFTERNOON SOUNDING ALSO
SUGGEST STEEP LAPSE RATES REMAINING IN PLACE THROUGH THE DENDRITIC
LAYER. THIS SHOULD HELP PRODUCE SOME HEAVIER AREAS OF SNOWFALL AS
THE PRECIPITATION BECOMES MORE CONVECTIVE THROUGH THE AFTERNOON.
SNOW AMOUNTS IN THE 4-8 INCH RANGE EXPECTED OVER 9000 FEET IN
PORTIONS OF THE CENTRAL AND NORTHERN MOUNTAINS WITH LOCALLY HIGHER
ON FAVORED SLOPES. AGAIN FEEL THAT THE GUSTY WINDS AND NEAR
WHITEOUT CONDITIONS WILL KEEP A THREAT OF HAZARDOUS TRAVEL
CONDITIONS IN PLACE AND HAVE HOISTED AN ADVISORY THROUGH FRIDAY
EVENING. THERE LOOKS TO BE A SHORT BREAK MOVE THROUGH THE EARLY
MORNING HOURS ON SATURDAY BEFORE ANOTHER SURGE OF MID LEVEL ENERGY
AND JET LEVEL WINDS INCREASE SNOW INTENSITY ON SATURDAY. THE ONE
CAVEAT IS SNOW MAY NOT ENTIRELY END ACROSS THE PORTIONS OF THE
PARK AND GORE RANGE WHERE THE OROGRAPHIC WINDS REMAIN FAVORABLE.
TEMPERATURES THROUGH THIS TIME WILL GRADUALLY WARM...ESPECIALLY IN
THE LOWER VALLEYS OF THE SOUTHWEST WHERE HIGHS SHOULD REACH BACK
TOWARD NORMAL. THE MOUNTAINS WILL WARM AS WELL BUT STILL REMAIN
FAVORABLE FOR SNOW REACHING INTO THE HIGH VALLEYS.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 344 PM MST THU FEB 20 2014
SNOW IS EXPECTED TO PICK UP AGAIN ACROSS THE NORTHERN CO MTNS SAT
AND SAT NIGHT AS ANOTHER WAVE EMBEDDED IN THE NORTHWEST FLOW
PASSES. 30-40 KT WESTERLY WINDS AT MTN TOP LEVEL WILL CONTINUE THE
WINDY CONDITIONS UP HIGH WITH AREAS OF BLOWING SNOW. SNOW LIKELY
TO EXTEND AS FAR SOUTH AS PERHAPS CRESTED BUTTE BUT ACCUMULATIONS
SHOULD TAPER RATHER QUICKLY SOUTH OF I-70. A DECREASING CHANCE OF
SNOW WILL LINGER ACROSS THE NORTHERN CO MTNS SUNDAY.
A HIGH AMPLITUDE RIDGE IS EXPECTED ALONG THE WEST COAST OF NORTH
AMERICA THE FIRST HALF OF NEXT WEEK WHILE A LARGE AREA OF LOW
PRESSURE RESIDES OVER ERN CANADA. THIS WILL GENERALLY KEEP DRIER
NORTHWEST FLOW ACROSS OUR FORECAST AREA BUT SHIFT JET STREAM TO OUR
NORTHEAST AS THE RIDGE BUILDS INTO THE GREAT BASIN. MODELS SHOW A
SMALL DISTURBANCE MOVING EAST ACROSS THE 4 CORNERS MONDAY FOR SOME
CLOUDS BUT NO PRECIP. MODELS ALSO SHOW A DISTURBANCE ROTATING AROUND
THE CANADIAN LOW BRUSHING OUR NORTHERN MTNS TUE-WED FOR A SLIGHT
CHANCE/CHANCE OF SNOW THERE. TEMPS WILL BE SEASONABLE.
A STRONG WESTERLY PACIFIC JET IS SHOWN UNDERCUTTING THE WESTERN
RIDGE AFTER WEDNESDAY AND QUICKLY PUNCHES MOISTURE INLAND ACROSS THE
GREAT BASIN. MODELS ARE IN GOOD AGREEMENT HERE...SO PRECIP CHANCES
SHOULD BE INCREASING THE LAST HALF OF NEXT WEEK. BUT WITH THE AIR
ORIGINATING OVER THE PACIFIC...WILL PROBABLY BE SEEING SNOW LEVELS
ON THE RISE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY EVENING)
ISSUED AT 945 PM MST THU FEB 20 2014
VFR CONDITIONS DOMINATE WITH CIGS 060-070 ONLY AT KCAG KHDN KSBS.
VFR CIGS WILL INCREASE ACROSS MUCH OF THE REGION TONIGHT. LOWERING
CLOUDS AND INCREASING PRECIPITATION OVER THE NORTHERN AND CENTRAL
COLORADO MOUNTAINS WILL BEGIN TO IMPACT THE KEGE AND KASE FLIGHT
TERMINALS TOWARD 12Z. LOWERED FLIGHT CRITERIA AT THESE TERMINALS
MAY PERSIST INTO THE AFTERNOON HOURS ON FRIDAY AS SNOW SHOWERS
PASS BY...BUT THEY SHOULD SHOW A GENERAL UPWARD TREND TOWARD VFR.
THE REMAINING FLIGHT TERMINALS SHOULD REMAIN AT VFR LEVELS. GUSTY
MOUNTAIN TOP WINDS WILL LEAD TO MECHANICAL TURBULENCE THROUGH THE
NEXT 24 HOURS.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...NONE.
UT...NONE.
&&
$$
UPDATES...JOE
SHORT TERM...15
LONG TERM...JAD
AVIATION...TGJT
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
947 PM MST THU FEB 20 2014
.UPDATE...
ISSUED AT 945 PM MST THU FEB 20 2014
SURFACE HIGH PRESSURE IS CENTERED OVER THE FOUR CORNERS AREA
TONIGHT BRINGING STRONGER INVERSIONS TO THE SOUTH AND THUS MUCH
COLDER TEMPERATURES THAN 24 HRS AGO. THE GRADIENT REMAINS TIGHT
ACROSS THE NORTH ESPECIALLY ALONG THE PARK/GORE RANGES. CLOUDS ARE
STRETCHED ALONG THE WYOMING BORDER AND ALONG THE CONTINENTAL
DIVIDE.
CONCERNING THE ADVISORIES IN THE NW COLORADO MTNS...THE 00Z NAM
PRODUCES ONLY VERY LIGHT SNOW ACROSS THE EASTERN MTNS TONIGHT AND
EVEN INTO FRIDAY. NAM AND RAP FORECAST SOUNDINGS SHOW THE PROFILE
BECOMING MUCH MORE STABLE IN MILD 700MB WARM ADVECTION BUT ALSO
THE PROFILE IS NOT FULLY SATURATING. THE PROFILE BECOMES MILDLY
UNSTABLE THROUGH A SHALLOW LAYER TO ABOUT 11KFT ON FRIDAY. ITS NOT
UNTIL AROUND SUNSET FRIDAY THAT A 100KT JET NOSES IN FROM THE NW
AND PRODUCES SOME ADDITIONAL FORCING THAT SNOW REALLY STARTS TO
ACCUMULATE. WILL LOOK CLOSELY AT THE NEW GFS AND THE CURRENT
HIGHLIGHTS TONIGHT.
ELSEWHERE AFTER A COLD START TO THE DAY EXPECT PERIODS OF CLOUDS
AND DAYTIME TEMPERATURES RECOVERING TO JUST BELOW NORMAL.
&&
.SHORT TERM...(TONIGHT THROUGH FRIDAY NIGHT)
ISSUED AT 344 PM MST THU FEB 20 2014
THE LAST STORM SYSTEM HAS MOVED ONTO THE PLAINS WHERE IT IS
PRODUCING SEVERE WEATHER THIS AFTERNOON. IN IT/S WAKE...COLDER
TEMPERATURES AND ISOLATED TO SCATTERED SHOWERS PERSIST ACROSS THE
DIVIDE MOUNTAINS. WINDS ALSO CONTINUE TO GUST OVER 35 MPH ALONG THE
SPINE OF THE ROCKIES AND THIS IS LIKELY TO CONTINUE OVER THE NEXT
FEW DAYS AS FAST NORTHWEST FLOW WAVERS OVER SOUTHERN WYOMING AND
NORTHERN COLORADO. THE INFUSION OF PACIFIC MOISTURE AND EMBEDDED
ENERGY WILL BRING WAVES OF SNOW TO THE REGION WITH THE NEXT BATCH
EXPECTED OVERNIGHT. 290-300K MOISTURE TRANSPORT VECTORS SHOW THIS
MOISTURE ARRIVING THROUGH THE EVENING ALONG WITH AN INCREASE IN JET
LEVEL WINDS. WAA INCREASES WITH THE APPROACH OF MID LEVEL ENERGY
AND THIS DEEPENS THE DENDRITIC LAYER UP NORTH AS THE LOWER PORTION
OF THE SOUNDING APPROACHES ISOTHERMAL. NEGATIVE EPV VALUES JUST
ABOVE THIS LAYER ALSO SUGGEST SOME POTENTIAL FOR BETTER SNOWFALL
PRODUCTION ACROSS THE NORTHERN MOUNTAINS THROUGH SUNRISE. THOUGH
MID LEVEL TEMPERATURES ARE WARMING...AFTERNOON SOUNDING ALSO
SUGGEST STEEP LAPSE RATES REMAINING IN PLACE THROUGH THE DENDRITIC
LAYER. THIS SHOULD HELP PRODUCE SOME HEAVIER AREAS OF SNOWFALL AS
THE PRECIPITATION BECOMES MORE CONVECTIVE THROUGH THE AFTERNOON.
SNOW AMOUNTS IN THE 4-8 INCH RANGE EXPECTED OVER 9000 FEET IN
PORTIONS OF THE CENTRAL AND NORTHERN MOUNTAINS WITH LOCALLY HIGHER
ON FAVORED SLOPES. AGAIN FEEL THAT THE GUSTY WINDS AND NEAR
WHITEOUT CONDITIONS WILL KEEP A THREAT OF HAZARDOUS TRAVEL
CONDITIONS IN PLACE AND HAVE HOISTED AN ADVISORY THROUGH FRIDAY
EVENING. THERE LOOKS TO BE A SHORT BREAK MOVE THROUGH THE EARLY
MORNING HOURS ON SATURDAY BEFORE ANOTHER SURGE OF MID LEVEL ENERGY
AND JET LEVEL WINDS INCREASE SNOW INTENSITY ON SATURDAY. THE ONE
CAVEAT IS SNOW MAY NOT ENTIRELY END ACROSS THE PORTIONS OF THE
PARK AND GORE RANGE WHERE THE OROGRAPHIC WINDS REMAIN FAVORABLE.
TEMPERATURES THROUGH THIS TIME WILL GRADUALLY WARM...ESPECIALLY IN
THE LOWER VALLEYS OF THE SOUTHWEST WHERE HIGHS SHOULD REACH BACK
TOWARD NORMAL. THE MOUNTAINS WILL WARM AS WELL BUT STILL REMAIN
FAVORABLE FOR SNOW REACHING INTO THE HIGH VALLEYS.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 344 PM MST THU FEB 20 2014
SNOW IS EXPECTED TO PICK UP AGAIN ACROSS THE NORTHERN CO MTNS SAT
AND SAT NIGHT AS ANOTHER WAVE EMBEDDED IN THE NORTHWEST FLOW
PASSES. 30-40 KT WESTERLY WINDS AT MTN TOP LEVEL WILL CONTINUE THE
WINDY CONDITIONS UP HIGH WITH AREAS OF BLOWING SNOW. SNOW LIKELY
TO EXTEND AS FAR SOUTH AS PERHAPS CRESTED BUTTE BUT ACCUMULATIONS
SHOULD TAPER RATHER QUICKLY SOUTH OF I-70. A DECREASING CHANCE OF
SNOW WILL LINGER ACROSS THE NORTHERN CO MTNS SUNDAY.
A HIGH AMPLITUDE RIDGE IS EXPECTED ALONG THE WEST COAST OF NORTH
AMERICA THE FIRST HALF OF NEXT WEEK WHILE A LARGE AREA OF LOW
PRESSURE RESIDES OVER ERN CANADA. THIS WILL GENERALLY KEEP DRIER
NORTHWEST FLOW ACROSS OUR FORECAST AREA BUT SHIFT JET STREAM TO OUR
NORTHEAST AS THE RIDGE BUILDS INTO THE GREAT BASIN. MODELS SHOW A
SMALL DISTURBANCE MOVING EAST ACROSS THE 4 CORNERS MONDAY FOR SOME
CLOUDS BUT NO PRECIP. MODELS ALSO SHOW A DISTURBANCE ROTATING AROUND
THE CANADIAN LOW BRUSHING OUR NORTHERN MTNS TUE-WED FOR A SLIGHT
CHANCE/CHANCE OF SNOW THERE. TEMPS WILL BE SEASONABLE.
A STRONG WESTERLY PACIFIC JET IS SHOWN UNDERCUTTING THE WESTERN
RIDGE AFTER WEDNESDAY AND QUICKLY PUNCHES MOISTURE INLAND ACROSS THE
GREAT BASIN. MODELS ARE IN GOOD AGREEMENT HERE...SO PRECIP CHANCES
SHOULD BE INCREASING THE LAST HALF OF NEXT WEEK. BUT WITH THE AIR
ORIGINATING OVER THE PACIFIC...WILL PROBABLY BE SEEING SNOW LEVELS
ON THE RISE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY EVENING)
ISSUED AT 945 PM MST THU FEB 20 2014
VFR CONDITIONS DOMINATE WITH CIGS 060-070 ONLY AT KCAG KHDN KSBS.
VFR CIGS WILL INCREASE ACROSS MUCH OF THE REGION TONIGHT. LOWERING
CLOUDS AND INCREASING PRECIPITATION OVER THE NORTHERN AND CENTRAL
COLORADO MOUNTAINS WILL BEGIN TO IMPACT THE KEGE AND KASE FLIGHT
TERMINALS TOWARD 12Z. LOWERED FLIGHT CRITERIA AT THESE TERMINALS
MAY PERSIST INTO THE AFTERNOON HOURS ON FRIDAY AS SNOW SHOWERS
PASS BY...BUT THEY SHOULD SHOW A GENERAL UPWARD TREND TOWARD VFR.
THE REMAINING FLIGHT TERMINALS SHOULD REMAIN AT VFR LEVELS. GUSTY
MOUNTAIN TOP WINDS WILL LEAD TO MECHANICAL TURBULENCE THROUGH THE
NEXT 24 HOURS.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WINTER WEATHER ADVISORY UNTIL 11 PM MST FRIDAY ABOVE 9000 FEET
FOR COZ004-010-013.
UT...NONE.
&&
$$
UPDATE...JOE
SHORT TERM...15
LONG TERM...JAD
AVIATION...TGJT
AREA FORECAST DISCUSSION
NWS ALBANY NY
105 PM EST FRI FEB 21 2014
.SYNOPSIS...
A COLD FRONT WILL CROSS THE REGION THIS AFTERNOON...ACCOMPANIED BY A
PERIOD OF RAIN SHOWERS WITH SOME DOWNPOURS AND ISOLATED THUNDER.
BEHIND THE FRONT...DRIER AIR WILL FILTER INTO THE REGION TONIGHT.
THE AIR MASS BEHIND THE COLD FRONT WILL STILL BE RELATIVELY
MILD...SO ABOVE NORMAL TEMPERATURES ARE EXPECTED TO CONTINUE THROUGH
MUCH OF THE WEEKEND. MUCH COLDER AIR WILL MOVE INTO THE REGION NEXT
WEEK.
&&
.NEAR TERM /UNTIL 7 PM THIS EVENING/...
AS OF 1245 PM...TEMPERATURES CONTINUE TO ONLY SLOWLY RISE IN MOST
AREAS EARLY THIS AFTERNOON DUE TO DEEP SNOWPACK AND NORTHERLY
AGEOSTROPHIC WIND COMPONENT. MANY LOCATIONS STILL HAVE
TEMPERATURES IN THE MID TO UPPER 30S...ALTHOUGH HIGHER TERRAIN
AREAS TO THE WEST AND EAST OF ALBANY HAVE WARMED INTO THE 40S WITH
EVEN A POCKET OF LOWER 50S IN PARTS OF SCHOHARIE COUNTY. WE ARE
EXPECTING A BRIEF SPIKE IN TEMPS IN THE UPPER 30S TO MID 40S
IMMEDIATELY PRECEDING THE COLD FRONT...WHICH AS OF NOON WAS
PROGRESSING EASTWARD THROUGH CENTRAL NY/PA. THE FRONT SHOULD
CONTINUE TO MAKE STEADY PROGRESS EASTWARD AS THERE ARE GOOD
PRESSURE RISES BEHIND THE FRONT.
THE COLD FRONT IS STILL EXPECTED TO MOVE FROM WEST TO EAST ACROSS
THE AREA DURING THE MID TO LATE AFTERNOON HOURS. A STRONGLY
FORCED LINE OF SHOWERS WITH DOWNPOURS...AND POSSIBLY ISOLATED
THUNDERSTORMS...WILL MOVE ACROSS THE AREA. THIS SCENARIO IS STILL
BEING WELL-DEPICTED BY THE HRRR AND LOCAL HIRES WRF AS
WELL. TIMING LOOKS TO BE BASICALLY FROM 1 PM THROUGH 6 PM.
SHOWALTER VALUES LOOK TO BE JUST BELOW ZERO...SO SOME ELEVATED
INSTABILITY IS POSSIBLE FOR A RUMBLE OR TWO OF THUNDER...BUT NO
STRONG/SEVERE STORMS ARE ANTICIPATED DUE TO MEAGER SURFACE BASED
INSTABILITY. ONCE THE FRONT GOES THROUGH...THE THREAT FOR SHOWERS
WILL DIMINISH GREATLY...AND TEMPS WILL START TO FALL ONCE AGAIN.
WITH THE PASSAGE OF THE BOUNDARY...THERE MAY BE A FEW STRONGER GUSTS
OF WIND...ESP OVER THE HIGHER TERRAIN. THE BETTER CHANCE FOR STRONG
WINDS MAY BE BEHIND THE FRONT...AS COOLER AIR ALOFT ALLOWS FOR
BETTER MIXING.
&&
.SHORT TERM /7 PM THIS EVENING THROUGH SUNDAY NIGHT/...
BEHIND THE COLD FRONT...COOLER AIR ALOFT WILL MOVE INTO THE
REGION AS THE STORM STORM LIFTS UP TOWARDS HUDSON BAY CANADA WITH
850 HPA TEMPS DROPPING BACK BELOW FREEZING. GUSTY W-SW WINDS WILL
BE IN PLACE FOR TONIGHT. WHILE MOST AREAS WILL STAY DRY...SOME
LINGERING CYCLONIC FLOW RAIN/SNOW SHOWERS CANNOT BE TOTALLY RULED
OUT FOR UPSLOPE FAVORED AREAS OF THE WESTERN ADIRONDACKS FOR
TONIGHT INTO SATURDAY. OTHERWISE...IT WILL REMAIN DRY. MIN TEMPS
WILL BE IN THE 20S TONIGHT. GOOD MIXING TOMORROW WILL PROMOTE A
MILD DAY...DESPITE BEING BEHIND THE COLD FRONT...WITH HIGHS
RANGING FROM THE MID TO UPPER 30S IN THE HIGH TERRAIN TO THE MID
TO UPPER 40S FOR VALLEY AREAS. TEMPS LOOK TO DROP BACK DOWN IN THE
TEENS AND 20S FOR SAT NIGHT WITH MAINLY DRY WEATHER.
THE MODELS SHOW A QUICK MOVING STORM SYSTEM AFFECTING THE REGION AT
SOME POINT BETWEEN SUNDAY AND SUNDAY NIGHT. THE TRACK AND TIMING OF
THIS SYSTEM REMAINS IN QUESTION...BUT ALL MODELS AGREE THAT ANY QPF
WOULD BE VERY LIGHT...AND IT LOOKS TO MOVE THROUGH RATHER QUICKLY.
WITH PRECIP ON THE NORTHERN SIDE OF THE SYSTEM...AND WITH EXPECTED
COLDER TEMPS ALOFT...MOST OF THE PRECIP SHOULD BE SNOW...PERHAPS
MIXING WITH A LITTLE BIT OF RAIN AT TIMES FOR VALLEY AREAS. JUST AN
INCH OR TWO OF SNOW LOOKS TO OCCUR. FOR NOW...WILL JUST GO WITH CHC
POPS FOR SUN/SUN NIGHT DUE TO UNCERTAINTY REGARDING ITS EXACT
TRACK/TIMING. MAX TEMPS WILL BE IN THE 30S...AND MINS SUNDAY NIGHT
LOOK TO BE IN THE TEENS/20S.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
MAINLY DRY AND VERY COLD CONDITIONS ARE EXPECTED FOR MUCH OF THE
LONG TERM PERIOD.
ANY CHANCES FOR PCPN WILL BE MAINLY TIED TO LAKE EFFECT DOWNWIND OF
LAKE ONTARIO ALTHOUGH A WEAK COASTAL LOW PASSES SOUTHEAST OF OUR
REGION ON TUESDAY WITH A STRONGER COASTAL LOW FOLLOWING A SIMILAR
TRACK ON WEDNESDAY. SINCE THIS SYSTEM LOOKS TO BE STRONGER AND TRACK
A LITTLE CLOSER TO OUR REGION WILL PLACE SLIGHT CHANCE POPS IN THE
GRIDS FOR NOW. IN ADDITION TO THE VERY COLD AIR IN PLACE ACRS OUR
REGION WIND CHILLS MAY REACH ADVISORY CRITERIA WEDNESDAY NIGHT AND
THURSDAY ACRS THE HIGHER TERRAIN. THIS WILL BE MENTIONED IN THE HWO.
AS FOR TEMPS EXPECT HIGHS ON MONDAY TO RANGE FROM THE UPPER TEENS
NORTHWEST TO MID 30S SOUTHEAST WITH HIGHS TUESDAY...WEDNESDAY AND
THURSDAY RANGING FROM THE MID TEENS NORTHWEST TO UPPER 20S
SOUTHEAST. LOWS MONDAY NIGHT WILL BE IN THE SINGLE DIGITS TO LOWER
TEENS WITH LOWS TUESDAY NIGHT AND WEDNESDAY NIGHT MAINLY IN THE 5
BELOW TO 10 ABOVE ZERO RANGE.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
THE 2 TO 3 HOUR BAND OF RAIN ASSOCIATED WITH COLD FRONT THAT WILL
MOVE THROUGH THE REGION THIS AFTERNOON...WILL BEGIN TO AFFECT THE
TAF SITES BETWEEN 19Z AND 20Z...AND THEN DEPART BETWEEN 22Z AND 23Z.
WITH IFR/MVFR CONDITONS ALREADY OCCURRING AHEAD OF THIS
RAINFALL...HAVE FORECAST IFR/MVFR CONDITIONS AT THE TAF SITES
THROUGH 22Z-23Z. AFTER 23Z DRIER AIR WILL MOVE IN AND CIGS MAY
REMAIN MVFR FOR SEVERAL MORE HOURS...THEN EXPECT SKIES TO BECOME
MAINLY CLEAR AFTER MIDNIGHT AT ALL THE TAF SITES.
WINDS WILL BE LIGHT AND VARIABLE AT THE TAF SITES EXPECT FOR KALB
WHERE WINDS WILL BE SOUTH AT AROUND 10 KTS WITH GUSTS OF AROUND 15
KTS. BEHIND THE FRON THE WINDS WILL BECOME WEST OR SOUTHWEST AT 5 TO
10 KTS...BUT GUST UP TO 15 TO 18 KTS AT KALB AND KPSF. THE WINDS
WILL DECREASE OVERNIGHT...BUT THEN PICK UP AGAIN FROM THE SOUTHWEST
AT 08 TO 14 KTS BY MID MORNING SATURDAY...WITH GUSTS ABOVE 20 KTS...
ESPECIALLY AT KALB.
OUTLOOK...
SATURDAT AFTERNOON AND NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SUNDAY-SUNDAY NIGHT: LOW OPERATIONAL IMPACT. CHANCE OF SHRA...SHSN.
MONDAY-MONDAY NIGHT: LOW OPERATIONAL IMPACT. BREEZY. NO SIG WX.
TUESDAY: NO OPERATIONAL IMPACT. NO SIG WX.
TUESDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN.
&&
.HYDROLOGY...
THE SNOW DEPTH ACROSS EAST CENTRAL NEW YORK AND ADJACENT WESTERN NEW
ENGLAND CONTINUES TO GENERALLY RANGE FROM 10 TO 30 INCHES...WITH
SOME HIGHER AMOUNTS IN THE MOUNTAINS. NOT MUCH SNOW MELT OCCURRED
OVERNIGHT INTO THIS MORNING DUE TO TEMPERATURES REMAINING IN THE 30S.
TEMPERATURES HAVE BEEN SLOW TO WARM TODAY...WITH HIGHS EXPECTED TO
BE IN THE UPPER 30S TO MID 40S THIS AFTERNOON. MORE RAIN WILL OCCUR
THIS AFTERNOON AHEAD OF AND ALONG A COLD FRONT PASSING THROUGH FROM
WEST TO EAST. THERE WILL LIKELY BE SOME DOWNPOURS...WHICH COMBINED
WITH SNOWPACK...COULD CAUSE PONDING AND/OR MINOR FLOODING OF URBAN
AREAS AND POOR DRAINAGE LOCATIONS DUE TO CLOGGED STORM DRAINS.
STORM TOTAL QPF STILL EXPECTED TO BE A HALF INCH TO NEARLY ONE AND A
HALF INCHES...WITH THE HIGHEST AMOUNTS ACROSS THE ADIRONDACKS.
HOWEVER...THIS QPF AND EXPECTED SNOW MELT WILL HAVE A LIMITED
RESPONSE ON AREA RIVERS AND STREAMS...AS MUCH OF IT WILL BE ABSORBED
BY THE DEEP SNOWPACK. THE LATEST MMEFS...AS WELL AS FORECASTS FROM
THE NERFC...DO NOT FORECAST ANY FLOODING OVER THE NEXT DAY OR
SO...ALTHOUGH THERE WILL BE SOME RISES ON AREA RIVERS AND STREAMS.
DRIER AIR WILL QUICKLY RETURN BEHIND THE COLD FRONT TONIGHT...WITH
TEMPERATURES DROPPING BACK BELOW FREEZING ACROSS THE ENTIRE REGION
BY EARLY SATURDAY MORNING. DAYTIME TEMPERATURES OVER THE WEEKEND
WILL CONTINUE TO BE ABOVE FREEZING...AND OVERNIGHT LOWS WILL DROP
BELOW FREEZING THIS WEEKEND. THIS SHOULD ALLOW FOR A STEADY
CONTROLLED SNOW MELT...WHICH WILL LIMIT ANY FLOODING CONCERNS. MUCH
COLDER WEATHER...WITH TEMPERATURES COMPLETELY BELOW FREEZING...WILL
RETURN FOR MUCH OF NEXT WEEK.
WE WILL CONTINUE TO MENTION POTENTIAL FOR ISOLATED ICE JAMS ON
SMALLER STREAMS AND CREEK IN THE HAZARDOUS WEATHER OUTLOOK FOR TODAY
INTO TONIGHT DUE TO RAIN MELT AND WARMER TEMPERATURES...BUT
WIDESPREAD FLOOD ISSUES ARE NOT ANTICIPATED AT THIS TIME.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...JPV
NEAR TERM...FRUGIS/GJM/JPV
SHORT TERM...FRUGIS
LONG TERM...11
AVIATION...GJM
HYDROLOGY...FRUGIS/JPV
AREA FORECAST DISCUSSION
NWS ALBANY NY
1246 PM EST FRI FEB 21 2014
.SYNOPSIS...
A COLD FRONT WILL CROSS THE REGION THIS AFTERNOON...ACCOMPANIED BY A
PERIOD OF RAIN SHOWERS WITH SOME DOWNPOURS AND ISOLATED THUNDER.
BEHIND THE FRONT...DRIER AIR WILL FILTER INTO THE REGION TONIGHT.
THE AIR MASS BEHIND THE COLD FRONT WILL STILL BE RELATIVELY
MILD...SO ABOVE NORMAL TEMPERATURES ARE EXPECTED TO CONTINUE THROUGH
MUCH OF THE WEEKEND. MUCH COLDER AIR WILL MOVE INTO THE REGION NEXT
WEEK.
&&
.NEAR TERM /UNTIL 7 PM THIS EVENING/...
AS OF 1245 PM...TEMPERATURES CONTINUE TO ONLY SLOWLY RISE IN MOST
AREAS EARLY THIS AFTERNOON DUE TO DEEP SNOWPACK AND NORTHERLY
AGEOSTROPHIC WIND COMPONENT. MANY LOCATIONS STILL HAVE
TEMPERATURES IN THE MID TO UPPER 30S...ALTHOUGH HIGHER TERRAIN
AREAS TO THE WEST AND EAST OF ALBANY HAVE WARMED INTO THE 40S WITH
EVEN A POCKET OF LOWER 50S IN PARTS OF SCHOHARIE COUNTY. WE ARE
EXPECTING A BRIEF SPIKE IN TEMPS IN THE UPPER 30S TO MID 40S
IMMEDIATELY PRECEDING THE COLD FRONT...WHICH AS OF NOON WAS
PROGRESSING EASTWARD THROUGH CENTRAL NY/PA. THE FRONT SHOULD
CONTINUE TO MAKE STEADY PROGRESS EASTWARD AS THERE ARE GOOD
PRESSURE RISES BEHIND THE FRONT.
THE COLD FRONT IS STILL EXPECTED TO MOVE FROM WEST TO EAST ACROSS
THE AREA DURING THE MID TO LATE AFTERNOON HOURS. A STRONGLY
FORCED LINE OF SHOWERS WITH DOWNPOURS...AND POSSIBLY ISOLATED
THUNDERSTORMS...WILL MOVE ACROSS THE AREA. THIS SCENARIO IS STILL
BEING WELL-DEPICTED BY THE HRRR AND LOCAL HIRES WRF AS
WELL. TIMING LOOKS TO BE BASICALLY FROM 1 PM THROUGH 6 PM.
SHOWALTER VALUES LOOK TO BE JUST BELOW ZERO...SO SOME ELEVATED
INSTABILITY IS POSSIBLE FOR A RUMBLE OR TWO OF THUNDER...BUT NO
STRONG/SEVERE STORMS ARE ANTICIPATED DUE TO MEAGER SURFACE BASED
INSTABILITY. ONCE THE FRONT GOES THROUGH...THE THREAT FOR SHOWERS
WILL DIMINISH GREATLY...AND TEMPS WILL START TO FALL ONCE AGAIN.
WITH THE PASSAGE OF THE BOUNDARY...THERE MAY BE A FEW STRONGER GUSTS
OF WIND...ESP OVER THE HIGHER TERRAIN. THE BETTER CHANCE FOR STRONG
WINDS MAY BE BEHIND THE FRONT...AS COOLER AIR ALOFT ALLOWS FOR
BETTER MIXING.
&&
.SHORT TERM /7 PM THIS EVENING THROUGH SUNDAY NIGHT/...
BEHIND THE COLD FRONT...COOLER AIR ALOFT WILL MOVE INTO THE
REGION AS THE STORM STORM LIFTS UP TOWARDS HUDSON BAY CANADA WITH
850 HPA TEMPS DROPPING BACK BELOW FREEZING. GUSTY W-SW WINDS WILL
BE IN PLACE FOR TONIGHT. WHILE MOST AREAS WILL STAY DRY...SOME
LINGERING CYCLONIC FLOW RAIN/SNOW SHOWERS CANNOT BE TOTALLY RULED
OUT FOR UPSLOPE FAVORED AREAS OF THE WESTERN ADIRONDACKS FOR
TONIGHT INTO SATURDAY. OTHERWISE...IT WILL REMAIN DRY. MIN TEMPS
WILL BE IN THE 20S TONIGHT. GOOD MIXING TOMORROW WILL PROMOTE A
MILD DAY...DESPITE BEING BEHIND THE COLD FRONT...WITH HIGHS
RANGING FROM THE MID TO UPPER 30S IN THE HIGH TERRAIN TO THE MID
TO UPPER 40S FOR VALLEY AREAS. TEMPS LOOK TO DROP BACK DOWN IN THE
TEENS AND 20S FOR SAT NIGHT WITH MAINLY DRY WEATHER.
THE MODELS SHOW A QUICK MOVING STORM SYSTEM AFFECTING THE REGION AT
SOME POINT BETWEEN SUNDAY AND SUNDAY NIGHT. THE TRACK AND TIMING OF
THIS SYSTEM REMAINS IN QUESTION...BUT ALL MODELS AGREE THAT ANY QPF
WOULD BE VERY LIGHT...AND IT LOOKS TO MOVE THROUGH RATHER QUICKLY.
WITH PRECIP ON THE NORTHERN SIDE OF THE SYSTEM...AND WITH EXPECTED
COLDER TEMPS ALOFT...MOST OF THE PRECIP SHOULD BE SNOW...PERHAPS
MIXING WITH A LITTLE BIT OF RAIN AT TIMES FOR VALLEY AREAS. JUST AN
INCH OR TWO OF SNOW LOOKS TO OCCUR. FOR NOW...WILL JUST GO WITH CHC
POPS FOR SUN/SUN NIGHT DUE TO UNCERTAINTY REGARDING ITS EXACT
TRACK/TIMING. MAX TEMPS WILL BE IN THE 30S...AND MINS SUNDAY NIGHT
LOOK TO BE IN THE TEENS/20S.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
MAINLY DRY AND VERY COLD CONDITIONS ARE EXPECTED FOR MUCH OF THE
LONG TERM PERIOD.
ANY CHANCES FOR PCPN WILL BE MAINLY TIED TO LAKE EFFECT DOWNWIND OF
LAKE ONTARIO ALTHOUGH A WEAK COASTAL LOW PASSES SOUTHEAST OF OUR
REGION ON TUESDAY WITH A STRONGER COASTAL LOW FOLLOWING A SIMILAR
TRACK ON WEDNESDAY. SINCE THIS SYSTEM LOOKS TO BE STRONGER AND TRACK
A LITTLE CLOSER TO OUR REGION WILL PLACE SLIGHT CHANCE POPS IN THE
GRIDS FOR NOW. IN ADDITION TO THE VERY COLD AIR IN PLACE ACRS OUR
REGION WIND CHILLS MAY REACH ADVISORY CRITERIA WEDNESDAY NIGHT AND
THURSDAY ACRS THE HIGHER TERRAIN. THIS WILL BE MENTIONED IN THE HWO.
AS FOR TEMPS EXPECT HIGHS ON MONDAY TO RANGE FROM THE UPPER TEENS
NORTHWEST TO MID 30S SOUTHEAST WITH HIGHS TUESDAY...WEDNESDAY AND
THURSDAY RANGING FROM THE MID TEENS NORTHWEST TO UPPER 20S
SOUTHEAST. LOWS MONDAY NIGHT WILL BE IN THE SINGLE DIGITS TO LOWER
TEENS WITH LOWS TUESDAY NIGHT AND WEDNESDAY NIGHT MAINLY IN THE 5
BELOW TO 10 ABOVE ZERO RANGE.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
MUCH OF THE RAIN HAS ENDED AT LEAST FOR NOW AT THE TAF SITES WITH
THE NEXT BATCH OF RAIN AHEAD OF THE COLD FRONT NOT EXPECTED TO
ARRIVE UNTIL EARLY AFTERNOON. THE TAF SITES UP UNTIL THIS TIME ARE
EXPECTED TO BE MVFR AT KGFL AND KALB WITH IFR/LIFR CONDITIONS
EXPECTED AT KPSF AND KPOU WHERE FOG AND LOW STRATUS WL BE PRESENT.
IFR CONDITIONS ARE EXPECTED AT ALL OF THE TAF SITES STARTING ARND
18Z AS THE NEXT BATCH OF RAIN MOVES IN. A COLD FRONT WL SWEEP
THROUGH THE RGN LATE THIS AFTERNOON WITH SKIES BECOMING SKC THIS
EVENING IN THE WAKE OF THE COLD FRONT.
WINDS WILL BE LIGHT AND VARIABLE UNTIL EARLY AFTERNOON AND THEN
NE-SE ARND 5 KTS AHD OF THE FRONT AND WEST TO SOUTHWEST AT 6 TO 10
KTS IN THE WAKE OF THE COLD FRONT.
OUTLOOK...
SATURDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SUNDAY-SUNDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF
SHRA...SHSN.
MONDAY-MONDAY NIGHT: LOW OPERATIONAL IMPACT. BREEZY. NO SIG WX.
TUESDAY: NO OPERATIONAL IMPACT. NO SIG WX.
TUESDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN.
&&
.HYDROLOGY...
THE SNOW DEPTH ACROSS EAST CENTRAL NEW YORK AND ADJACENT WESTERN NEW
ENGLAND CONTINUES TO GENERALLY RANGE FROM 10 TO 30 INCHES...WITH
SOME HIGHER AMOUNTS IN THE MOUNTAINS. NOT MUCH SNOW MELT OCCURRED
OVERNIGHT INTO THIS MORNING DUE TO TEMPERATURES REMAINING IN THE 30S.
TEMPERATURES HAVE BEEN SLOW TO WARM TODAY...WITH HIGHS EXPECTED TO
BE IN THE UPPER 30S TO MID 40S THIS AFTERNOON. MORE RAIN WILL OCCUR
THIS AFTERNOON AHEAD OF AND ALONG A COLD FRONT PASSING THROUGH FROM
WEST TO EAST. THERE WILL LIKELY BE SOME DOWNPOURS...WHICH COMBINED
WITH SNOWPACK...COULD CAUSE PONDING AND/OR MINOR FLOODING OF URBAN
AREAS AND POOR DRAINAGE LOCATIONS DUE TO CLOGGED STORM DRAINS.
STORM TOTAL QPF STILL EXPECTED TO BE A HALF INCH TO NEARLY ONE AND A
HALF INCHES...WITH THE HIGHEST AMOUNTS ACROSS THE ADIRONDACKS.
HOWEVER...THIS QPF AND EXPECTED SNOW MELT WILL HAVE A LIMITED
RESPONSE ON AREA RIVERS AND STREAMS...AS MUCH OF IT WILL BE ABSORBED
BY THE DEEP SNOWPACK. THE LATEST MMEFS...AS WELL AS FORECASTS FROM
THE NERFC...DO NOT FORECAST ANY FLOODING OVER THE NEXT DAY OR
SO...ALTHOUGH THERE WILL BE SOME RISES ON AREA RIVERS AND STREAMS.
DRIER AIR WILL QUICKLY RETURN BEHIND THE COLD FRONT TONIGHT...WITH
TEMPERATURES DROPPING BACK BELOW FREEZING ACROSS THE ENTIRE REGION
BY EARLY SATURDAY MORNING. DAYTIME TEMPERATURES OVER THE WEEKEND
WILL CONTINUE TO BE ABOVE FREEZING...AND OVERNIGHT LOWS WILL DROP
BELOW FREEZING THIS WEEKEND. THIS SHOULD ALLOW FOR A STEADY
CONTROLLED SNOW MELT...WHICH WILL LIMIT ANY FLOODING CONCERNS. MUCH
COLDER WEATHER...WITH TEMPERATURES COMPLETELY BELOW FREEZING...WILL
RETURN FOR MUCH OF NEXT WEEK.
WE WILL CONTINUE TO MENTION POTENTIAL FOR ISOLATED ICE JAMS ON
SMALLER STREAMS AND CREEK IN THE HAZARDOUS WEATHER OUTLOOK FOR TODAY
INTO TONIGHT DUE TO RAIN MELT AND WARMER TEMPERATURES...BUT
WIDESPREAD FLOOD ISSUES ARE NOT ANTICIPATED AT THIS TIME.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...JPV
NEAR TERM...FRUGIS/GJM/JPV
SHORT TERM...FRUGIS
LONG TERM...11
AVIATION...GJM
HYDROLOGY...FRUGIS/JPV
AREA FORECAST DISCUSSION
NWS ALBANY NY
1032 AM EST FRI FEB 21 2014
.SYNOPSIS...
AHEAD OF A COLD FRONT...MILDER AIR WILL MOVE INTO THE REGION FOR
TODAY...ALONG WITH RAIN SHOWERS...GUSTY WINDS OVER THE HIGH
TERRAIN...AND A SLIGHT CHANCE FOR A THUNDERSTORM. AFTER THE FRONT
PASSES THROUGH THE REGION LATE TODAY...THE THREAT FOR RAIN SHOWERS
WILL END. DAYTIME TEMPERATURES WILL CONTINUE TO BE ABOVE NORMAL INTO
THE WEEKEND...BUT MUCH COLDER AIR WILL RETURN TO THE REGION FOR MUCH
OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1015 AM...TEMPS IN NY WERE ALL ABOVE FREEZING...WITH JUST A
FEW POCKETS OF BELOW FREEZING TEMPS IN SOUTHERN VERMONT AND
BERKSHIRE COUNTY. HOWEVER...RADAR INDICATES TO ADDITIONAL PCPN WILL
OCCUR IN SOUTHERN VERMONT AND BERKSHIRE COUNTY UNTIL THIS
AFTERNOON...AT WHICH TIME TEMPS WILL BE ABOVE FREEZING IN ALL AREAS
THERE AS WELL. AS A RESULT...HAVE CANCELLED ANY REMAINING WINTER
WEATHER ADVISORIES. HAVE ALSO MADE ADJUSTMETNS TO THE HOURLY TEMP
AND POP GRIDS TO REFLECT CURRENT CONDITIONS AND TRENDS.
.PREVIOUS DISCUSSION...
AS OF 621 AM EST...A STRONG STORM SYSTEM AND POTENT UPPER LEVEL
SHORTWAVE IS MOVING ACROSS THE UPPER GREAT LAKES. A WARM FRONT
ASSOCIATED WITH THIS STORM IS HAVING A TOUGH TIME MOVING ACROSS
OUR REGION...DUE TO PLENTY OF LOW LEVEL COLD AIR IN PLACE THANKS
TO A DEEP SNOW PACK. TEMPERATURES CONTINUE TO BE IN THE 30S ACROSS
OUR ENTIRE REGION.
STEADY PRECIPITATION HAS MOVED NORTH AND EAST OF THE REGION...AS
THE BEST ISENTROPIC LIFT/WARM AIR ADVECTION IS NOW FOCUSED ACROSS
NORTHERN NEW ENGLAND. WITH TEMPERATURES WARMING THROUGH THE 30S
AND MOST OF THE PRECIPITATION DONE...WE/VE CANCELLED THE WINTER
WEATHER ADVISORY FOR MOST OF THE AREA. WE WILL CONTINUE IT FOR A
LITTLE LONGER FOR THE EASTERN ADIRONDACKS...LAKE GEORGE AREA...AND
SRN VT...AS SOME LIGHT PRECIPITATION REMAINS THERE...AND SOME
POCKETS OF 30-32 DEGREES ARE STILL OCCURRING ACCORDING TO MESO OBS
AT THIS TIME. ONCE TEMPS WARM UP AND PRECIP ENDS...WE SHOULD BE
ABLE TO CANCEL THE ADVISORY.
AS SHOWN IN THE MODELS...THIS BREAK IN THE PRECIP LOOKS TO
CONTINUE THROUGH MUCH OF THE MORNING HOURS. WE HAVE LOWERED POPS
TO CHC THROUGH THE MID MORNING HOURS FOR CENTRAL/SOUTHERN PARTS OF
THE AREA. HOWEVER...THE MOIST SOUTHERLY FLOW...COMBINED WITH SOME
UPSLOPE...MAY ALLOW FOR SOME SPOTTY AREAS OF LIGHT RAIN SHOWERS BY
LATER THIS MORNING...SO WE WILL RAISE POPS BACK UP TO LIKELY FOR
THE LATE MORNING HOURS. MAX TEMPS SHOULD WARM UP INTO THE LOWER TO
MID 40S FOR VALLEY AREAS...WITH UPPER 30S IN THE HIGH TERRAIN WITH
THESE HIGHS IN THE LATE MORNING TO EARLY AFTERNOON.
THE STORM/S COLD FRONT LOOKS TO MOVE FROM WEST TO EAST DURING THE
AFTERNOON HOURS. A STRONGLY FORCED LINE OF SHOWERS...AND POSSIBLY
SOME ISOLATED THUNDERSTORMS...WILL MOVE ACROSS THE AREA. THIS IS
SEEN IN THE 09Z 3KM HRRR AS WELL...WITH THE TIMING ACROSS OUR
AREA BASICALLY FROM 1 PM THROUGH 5 PM. SHOWALTER VALUES LOOK TO BE
JUST BELOW ZERO...SO SOME ELEVATED INSTABILITY IS POSSIBLE FOR A
RUMBLE OR TWO OF THUNDER...BUT NO STRONG/SEVERE STORMS ARE
ANTICIPATED DUE TO MEAGER SURFACE BASED INSTABILITY. ONCE THE
FRONT GOES THROUGH...THE THREAT FOR SHOWERS WILL DIMINISH
GREATLY...AND TEMPS WILL START TO FALL ONCE AGAIN.
WITH THE PASSAGE OF THE BOUNDARY...THERE MAY BE A FEW STRONGER GUSTS
OF WIND...ESP OVER THE HIGHER TERRAIN. THE BETTER CHANCE FOR STRONG
WINDS MAY BE BEHIND THE FRONT...AS COOLER AIR ALOFT ALLOWS FOR
BETTER MIXING.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/...
BEHIND THE COLD FRONT...COOLER AIR ALOFT WILL MOVE INTO THE
REGION AS THE STORM STORM LIFTS UP TOWARDS HUDSON BAY CANADA WITH
850 HPA TEMPS DROPPING BACK BELOW FREEZING. GUSTY W-SW WINDS WILL
BE IN PLACE FOR TONIGHT. WHILE MOST AREAS WILL STAY DRY...SOME
LINGERING CYCLONIC FLOW RAIN/SNOW SHOWERS CANNOT BE TOTALLY RULED
OUT FOR UPSLOPE FAVORED AREAS OF THE WESTERN ADIRONDACKS FOR
TONIGHT INTO SATURDAY. OTHERWISE...IT WILL REMAIN DRY. MIN TEMPS
WILL BE IN THE 20S TONIGHT. GOOD MIXING TOMORROW WILL PROMOTE A
MILD DAY...DESPITE BEING BEHIND THE COLD FRONT...WITH HIGHS
RANGING FROM THE MID TO UPPER 30S IN THE HIGH TERRAIN TO THE MID
TO UPPER 40S FOR VALLEY AREAS. TEMPS LOOK TO DROP BACK DOWN IN THE
TEENS AND 20S FOR SAT NIGHT WITH MAINLY DRY WEATHER.
THE MODELS SHOW A QUICK MOVING STORM SYSTEM AFFECTING THE REGION AT
SOME POINT BETWEEN SUNDAY AND SUNDAY NIGHT. THE TRACK AND TIMING OF
THIS SYSTEM REMAINS IN QUESTION...BUT ALL MODELS AGREE THAT ANY QPF
WOULD BE VERY LIGHT...AND IT LOOKS TO MOVE THROUGH RATHER QUICKLY.
WITH PRECIP ON THE NORTHERN SIDE OF THE SYSTEM...AND WITH EXPECTED
COLDER TEMPS ALOFT...MOST OF THE PRECIP SHOULD BE SNOW...PERHAPS
MIXING WITH A LITTLE BIT OF RAIN AT TIMES FOR VALLEY AREAS. JUST AN
INCH OR TWO OF SNOW LOOKS TO OCCUR. FOR NOW...WILL JUST GO WITH CHC
POPS FOR SUN/SUN NIGHT DUE TO UNCERTAINTY REGARDING ITS EXACT
TRACK/TIMING. MAX TEMPS WILL BE IN THE 30S...AND MINS SUNDAY NIGHT
LOOK TO BE IN THE TEENS/20S.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
MAINLY DRY AND VERY COLD CONDITIONS ARE EXPECTED FOR MUCH OF THE
LONG TERM PERIOD.
ANY CHANCES FOR PCPN WILL BE MAINLY TIED TO LAKE EFFECT DOWNWIND OF
LAKE ONTARIO ALTHOUGH A WEAK COASTAL LOW PASSES SOUTHEAST OF OUR
REGION ON TUESDAY WITH A STRONGER COASTAL LOW FOLLOWING A SIMILAR
TRACK ON WEDNESDAY. SINCE THIS SYSTEM LOOKS TO BE STRONGER AND TRACK
A LITTLE CLOSER TO OUR REGION WILL PLACE SLIGHT CHANCE POPS IN THE
GRIDS FOR NOW. IN ADDITION TO THE VERY COLD AIR IN PLACE ACRS OUR
REGION WIND CHILLS MAY REACH ADVISORY CRITERIA WEDNESDAY NIGHT AND
THURSDAY ACRS THE HIGHER TERRAIN. THIS WILL BE MENTIONED IN THE HWO.
AS FOR TEMPS EXPECT HIGHS ON MONDAY TO RANGE FROM THE UPPER TEENS
NORTHWEST TO MID 30S SOUTHEAST WITH HIGHS TUESDAY...WEDNESDAY AND
THURSDAY RANGING FROM THE MID TEENS NORTHWEST TO UPPER 20S
SOUTHEAST. LOWS MONDAY NIGHT WILL BE IN THE SINGLE DIGITS TO LOWER
TEENS WITH LOWS TUESDAY NIGHT AND WEDNESDAY NIGHT MAINLY IN THE 5
BELOW TO 10 ABOVE ZERO RANGE.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
MUCH OF THE RAIN HAS ENDED AT LEAST FOR NOW AT THE TAF SITES WITH
THE NEXT BATCH OF RAIN AHEAD OF THE COLD FRONT NOT EXPECTED TO
ARRIVE UNTIL EARLY AFTERNOON. THE TAF SITES UP UNTIL THIS TIME ARE
EXPECTED TO BE MVFR AT KGFL AND KALB WITH IFR/LIFR CONDITIONS
EXPECTED AT KPSF AND KPOU WHERE FOG AND LOW STRATUS WL BE PRESENT.
IFR CONDITIONS ARE EXPECTED AT ALL OF THE TAF SITES STARTING ARND
18Z AS THE NEXT BATCH OF RAIN MOVES IN. A COLD FRONT WL SWEEP
THROUGH THE RGN LATE THIS AFTERNOON WITH SKIES BECOMING SKC THIS
EVENING IN THE WAKE OF THE COLD FRONT.
WINDS WILL BE LIGHT AND VARIABLE UNTIL EARLY AFTERNOON AND THEN
NE-SE ARND 5 KTS AHD OF THE FRONT AND WEST TO SOUTHWEST AT 6 TO 10
KTS IN THE WAKE OF THE COLD FRONT.
OUTLOOK...
SATURDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SUNDAY-SUNDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF
SHRA...SHSN.
MONDAY-MONDAY NIGHT: LOW OPERATIONAL IMPACT. BREEZY. NO SIG WX.
TUESDAY: NO OPERATIONAL IMPACT. NO SIG WX.
TUESDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN.
&&
.HYDROLOGY...
THE SNOW DEPTH ACROSS EAST CENTRAL NEW YORK AND ADJACENT WESTERN
NEW ENGLAND ARE GENERALLY FROM 1 TO 3+ FEET.
TEMPERATURES ARE CURRENTLY IN THE LOWER TO MIDDLE 30S...WITH STEADY
RAIN AND FREEZING RAIN OCCURRING ACROSS THE NORTHERN HALF OF THE
REGION AS A WARM FRONT MOVES ACROSS THE REGION. WITH A SOUTHERLY
FLOW DEVELOPING...TEMPERATURES WILL BRIEFLY BE ABOVE NORMAL
TODAY...WITH HIGHS IN THE UPPER 30S TO MID 40S...ALONG WITH SOME
ADDITIONAL RAIN SHOWERS. HOWEVER...COLDER AIR WILL QUICKLY RETURN
BEHIND THIS AFTERNOON/S COLD FRONT...WITH TEMPERATURES DROPPING BACK
BELOW FREEZING ACROSS THE ENTIRE REGION BY TONIGHT.
STORM TOTAL QPF WILL BE A HALF INCH TO NEARLY ONE AND A HALF
INCHES...WITH THE HIGHEST AMOUNTS ACROSS THE ADIRONDACKS.
HOWEVER...THIS QPF AND EXPECTED SNOW MELT WILL HAVE A LIMITED
RESPONSE ON AREA RIVERS AND STREAMS...AS MUCH OF IT WILL BE ABSORBED
BY THE DEEP SNOWPACK. THE LATEST MMEFS...AS WELL AS FORECASTS FROM
THE NERFC...DO NOT FORECAST ANY FLOODING OVER THE NEXT DAY OR
SO...ALTHOUGH THERE WILL BE SOME RISES ON AREA RIVERS AND STREAMS.
DAYTIME TEMPERATURES OVER THE WEEKEND WILL CONTINUE TO BE ABOVE
FREEZING...AND OVERNIGHT LOWS WILL DROP BELOW FREEZING. THIS SHOULD
ALLOW FOR A STEADY CONTROLLED SNOW MELT...WHICH WILL LIMIT ANY
FLOODING CONCERNS. MUCH COLDER WEATHER...WITH TEMPERATURES
COMPLETELY BELOW FREEZING...WILL RETURN FOR MUCH OF NEXT WEEK.
WE WILL CONTINUE TO MENTION A SLIGHT CHC FOR AN ISOLATED ICE JAM ON
SMALLER STREAMS AND CREEK IN THE HWO STATEMENT FOR TODAY INTO
TONIGHT DUE TO RAIN MELT AND WARMER TEMPERATURES...BUT WIDESPREAD
FLOOD ISSUES ARE NOT ANTICIPATED AT THIS TIME.
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...WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
NYZ033-041>043-082>084.
MA...NONE.
VT...WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
VTZ013>015.
&&
$$
SYNOPSIS...FRUGIS
NEAR TERM...GJM/FRUGIS
SHORT TERM...FRUGIS
LONG TERM...11
AVIATION...11
HYDROLOGY...FRUGIS
AREA FORECAST DISCUSSION
NWS TAUNTON MA
729 AM EST FRI FEB 21 2014
.SYNOPSIS...
AN APPROACHING WARM FRONT BRINGS PERIODS OF RAIN AND DRIZZLE TO
THE AREA THIS MORNING...WITH POCKETS OF FREEZING RAIN TO THE
HIGHER TERRAIN. WARMER AIR THEN INVADES CONNECTICUT...RHODE ISLAND
AND EASTERN MASSACHUSETTS THIS AFTERNOON ALONG WITH GUSTY
SHOWERS...AN ISOLATED THUNDERSTORM AND LOCALLY HEAVY RAINFALL.
MILD WEATHER THIS WEEKEND FOLLOWED BY MUCH COLDER WEATHER NEXT
WEEK. A PERIOD OF SNOW IS POSSIBLE SUNDAY NIGHT AND AGAIN THE
MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
7 AM UPDATE...
LITTLE BREAK IN THE ACTION WITH MAJORITY OF THE WARM ADVECTION
PRECIP ACROSS NORTHERN NEW ENGLAND...WITH JUST ONE BAND LEFT
ACROSS EASTERN MA. OTHERWISE PRECIP FOR THE REMAINDER OF THIS
MORNING INTO EARLY THIS AFTERNOON SHOULD BE MAINLY LIGHT/NUISANCE
TYPE DRIZZLE AND/OR SPOTTY LIGHT RAIN. EXPECT COOL CONDITIONS MUCH
OF THE DAY WITH WARM SECTOR POSSIBLY PUNCHING INTO RI AND
SOUTHEAST MA LATER THIS AFTERNOON.
ONLY CHANGE TO THE FORECAST WAS TO HIT A BIT HARDER THE POTENTIAL
FOR ELEVATED CONVECTION ALONG AND AHEAD OF APPROACHING COLD FRONT.
SPC MESOANALYSIS INDICATES STEEP MID LEVEL LAPSE RATES ADVECTING
NORTHWARD FROM THE MID ATLC STATES. THIS COUPLED WITH FRONTAL
CONVERGENCE THIS AFTERNOON AND QG FORCING FROM STRONG UPPER LEVEL
JET SHOULD BE SUFFICIENT TO INITIATE ELEVATED CONVECTION. PAST FEW
RUNS OF HRRR SUPPORT THIS THINKING WITH THIS MODEL SIMULATING AN
ORGANIZED FINE LINE OF LOW TOP CONVECTION MOVING ACROSS THE AREA 3
PM TO 7 PM FROM WEST TO EAST. MAIN CONCERN IS IF CONVECTION FIRES
SUBTROPICAL MOISTURE PLUME WITH PWATS +3 STD FROM CLIMO YIELDS A
RISK OF HEAVY RAINFALL. THIS COMBINED WITH ALREADY SNOW CLOGGED
STORM DRAINS MAY RESULT IN WIDESPREAD STREET AND HIGHWAY FLOODING
DURING THE LATE DAY COMMUTE. THUS HAVE ISSUED A SPECIAL WEATHER
STATEMENT TO HEIGHTEN PUBLIC AWARENESS. FLY IN THE OINTMENT WILL
BE IF CONVECTION UPSTREAM ACROSS THE SOUTHEAST STATES ROBS
MOISTURE AND INSTABILITY FROM BEING TRANSPORTED NORTHWARD. DAY
SHIFT WILL HAVE TO MONITOR THIS. EARLIER DISCUSSION BELOW.
================================================================
4 AM UPDATE...THE FIRST OF TWO ROUNDS OF PRECIP IS OVER SOUTHERN NEW
ENGLAND CURRENTLY...WITH THE HEAVIEST PRECIP IN SOUTHERN NEW
HAMPSHIRE. THESE NEXT FEW HOURS WILL BE THE MOST COMPLICATED PART OF
THE FORECAST WITH THE SURFACE TEMPERATURES PLAYING SUCH AN IMPORTANT
ROLE. TEMPERATURES ACROSS THE AREA ARE HOVERING RIGHT AROUND
FREEZING WITH A FEW LOCATIONS BELOW FREEZING AND THE MAJORITY JUST
ABOVE. DEWPOINTS ARE ALSO JUST BELOW FREEZING SO ANY HEAVY
PRECIPITATION THAT MOVES OVER THOSE AREAS WILL LIKELY BE ENOUGH TO
COOL THE TEMPERATURES TO FREEZING OR JUST BELOW. ALOFT THE
ATMOSPHERE IS WARM ENOUGH NOW FOR PRECIPITATION TO BE FALLING AS
RAIN ACROSS SOUTHERN NEW ENGLAND. THE ONLY QUESTION IS WHETHER THE
TEMPERATURES AT THE SURFACE WILL BE ABOVE OR BELOW FREEZING. IN THE
AREAS WHERE THE TEMPERATURES ARE BELOW FREEZING OR FALL BELOW
FREEZING...ICING WILL BE A CONCERN. NOT EXPECTING MUCH IN THE WAY
OF ICING...LESS THAN A TENTH OF AN INCH...BUT EVEN THE LIGHTEST
AMOUNTS OF ICING CAN WREAK HAVOC ON TRAVEL. SO WILL LEAVE THE
WINTER WEATHER ADVISORY IN PLACE FOR PORTIONS OF MASSACHUSETTS AND
SOUTHERN NEW HAMPSHIRE.
BY MID-MORNING...TEMPERATURES SHOULD RISE ABOVE FREEZING
EVERYWHERE...ALLOWING ANY REMAINING PRECIPITATION TO FALL AS RAIN.
AT THIS POINT...THE CONCERN WILL TURN TO HEAVY RAIN AND THUNDER
POTENTIAL FOR THE AFTERNOON. A COLD FRONT APPROACHING THE AREA...A
STRENGTHENING LOW LEVEL JET...AND STEEPENING MID LEVEL LAPSE RATES
SHOULD PROVIDE ENOUGH LIFT AND INSTABILITY FOR A CONVECTIVE LINE OF
SHOWERS JUST AHEAD OF THE COLD FRONT. IN ADDITION...PRECIPITABLE
WATER VALUES ARE 3 STANDARD DEVIATIONS ABOVE NORMAL FOR THIS TIME OF
YEAR. SO ANY SHOWERS ARE LIKELY TO PRODUCE BRIEF HEAVY DOWNPOURS
AND WITH SNOW CLOGGED DRAINS...EXPECT SOME PONDING OF WATER ON ROADS
THIS AFTERNOON. DEPENDING ON THE TIMING OF THE FRONT AND THUS THE
SHOWERS AHEAD OF THE FRONT...THERE IS A POSSIBILITY OF SOME THUNDER
WITH THE LINE. HAVE KEPT A SLIGHT CHANCE OF THUNDER IN THE GRIDS FOR
THIS AFTERNOON. EXPECT THE FRONT TO MOVE THROUGH IN THE LATE
AFTERNOON INTO EARLY EVENING. IF IT COMES THROUGH DURING
DAYLIGHT...THERE WILL BE THAT INSTABILITY POTENTIAL...IF IT COMES
THROUGH LATER AFTER SOME OF THE HEATING FROM THE DAY IS
LOST...THUNDER IS LESS LIKELY.
DESPITE A RATHER HEFTY LOW LEVEL JET THE WARM AIR ALOFT WILL PREVENT
MOST OF THAT ENERGY FROM MIXING TO THE SURFACE. THE EXCEPTION TO
THIS WOULD BE IN ANY OF THOSE CONVECTIVE SHOWERS THAT OCCUR. HEAVY
RAIN IN THOSE SHOWERS COULD DRAG SOME OF THOSE STRONGER WINDS DOWN
TO THE SURFACE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SATURDAY/...
TONIGHT...AS THE COLD FRONT PUSHES OFFSHORE IT WILL TAKE THE PRECIP
WITH IT AND WE WILL BEGIN TO DRY OUT FOR A BIT. EXPECT SKIES TO
CLEAR FAIRLY QUICKLY BEHIND THE FRONT WITH MOSTLY CLEAR SKIES FOR
MUCH OF THE NIGHT. THE LOW LEVEL JET WILL KEEP WINDS FROM
DECOUPLING OVERNIGHT SO WILL NOT HAVE OPTIMAL RADIATIONAL COOLING
CONDITIONS. SO TEMPERATURES WILL REMAIN IN THE 20S TO MID 30S.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
HIGHLIGHTS...
* MILD THIS WEEKEND
* ARCTIC AIR RETURNS NEXT WEEK
* HIGH AMPLITUDE PATTERN OFFERS A CHANCE OF SNOW SUN NIGHT & AGAIN
MIDDLE OF NEXT WEEK
THIS WEEKEND...
SATURDAY...DRY POST FRONTAL AIRMASS OVERSPREADS THE REGION. HOWEVER
AIRMASS IS RELATIVELY MILD WITH 850 TEMPS AROUND -2C AND 925 MB
AROUND +4C. BUFKIT SOUNDINGS SUGGEST MIXING TO AROUND 925 MB WILL
PROMOTE MAX TEMPS 45-50. HOWEVER A GUSTY SW WIND OF 20-30 MPH WILL
PROVIDE A BIT OF A WIND CHILL. NEVERTHELESS PLEASANT BY LATE FEB
STANDARDS...ALONG WITH DRY WEATHER PREVAILING.
SUNDAY...THE 00Z NAM WAS A STRONG OUTLIER WITH ITS MID LEVEL
SHORTWAVE TROUGH. THUS FOLLOWED A BLEND OF THE 00Z ECMWF/GFS AND
GEFS SOLUTIONS WHICH SUGGEST A PERIOD OF SNOW POSSIBLE LATE SUN/SUN
NIGHT INTO EARLY MON AS A FRONTAL WAVE TRACKS SOUTH OF NEW ENGLAND.
ECMWF OFFERS ONLY UP TO A TENTH OF AN INCH OF QPF WHILE THE GFS
GENERATES SEVERAL TENTHS. GEFS SIDES WITH THE OPERATIONAL GFS. UPPER
AIR PATTERN FAVORS MINOR SNOW ACCUMULATIONS GIVEN THE LACK OF SHORT
WAVE AMPLITUDE AND PROGRESSIVE NATURE. NEVERTHELESS A FEW INCHES OF
SNOW ARE POSSIBLE LATE SUN INTO EARLY MON. OTHERWISE SUNDAY WILL
START OUT DRY AND RELATIVELY MILD...BUT COOLING LATER IN THE DAY AS
FRONTAL BOUNDARY SLIPS SOUTHWARD WITH COLD AIR ADVECTION COMMENCING.
NEXT WEEK...
TEMPERATURES...LOOKS LIKE A COLD STRETCH OF WEATHER WITH THE POLAR
FRONT SLIDING SOUTH OF NEW ENGLAND ALL OF NEXT WEEK AS ALL MODEL
GUIDANCE /INCLUDING GFS-ECMWF-ECENS-GEFS/ PROJECTING 850 TEMPS OF
AROUND -15C /-1 STD FROM CLIMO/ ACROSS THE AREA MON THROUGH WED.
COLDER CONDITIONS ARE POSSIBLE LATE NEXT WEEK AS ENSEMBLES AND
DETERMINISTIC GUIDANCE HINT AT ANOTHER ARCTIC SURGE ADVECTING INTO
THE NORTHEAST WITH 850 TEMPS LOWERING TO -20C TO -25C
/-2 STD FROM CLIMO/!
PRECIPITATION...DIFFICULT AT THIS RANGE TO TIME WAVES ALONG LEADING
AND SECONDARY FRONTAL SURGES NEXT WEEK. HOWEVER ALL MODEL GUIDANCE
/AT VARYING DEGREES/ FOCUSES PRECIP CHANCES AROUND MID WEEK
WITH CYCLOGENESIS OFF THE MID ATLC COAST. THEN QUESTION BECOMES HOW
CLOSE DOES SYSTEM TRACK TO THE COAST. JET ENERGY ASSOCIATED WITH
THIS SYSTEM IS CURRENTLY OVER THE ARCTIC...A VERY DATA SPARSE AREA.
THUS MODELS WILL NOT CAPTURE THE TRUE AMPLITUDE OF THIS FEATURE
UNTIL MON OR TUE WHEN IT TRACKS INTO A MORE DATA RICH AREA OVER
SOUTHERN CANADA/NORTHERN ROCKIES. THE UPPER AIR PATTERN DOES FAVOR
SOME DEGREE OF EAST COAST STORMINESS WITH A SPLIT FLOW REGIME ACROSS
THE WEST COAST WHICH INCLUDES AN ANOMALOUS WESTERN US/CANADA RIDGE
EXTENDING INTO AK. OTHERWISE...MUCH OF NEXT WEEK LOOKS COLD AND DRY.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
7 AM UPDATE...
NOT MUCH CHANGE FROM 06Z TAFS. MAIN CONCERN IS HEAVY SHOWERS WITH
EMBEDDED TSTMS 3 PM TO 7 PM FROM WEST TO EAST. EARLIER DISCUSSION
BELOW.
=================================================================
THROUGH 12Z...HIGH CONFIDENCE IN TRENDS...LOWER CONFIDENCE IN
TIMING. SEEING A MIX OF CONDITIONS...MAINLY MVFR/VFR...WITH A FEW
PATCHES OF IFR CONDITIONS. GENERALLY GOING TO SEE CONDITIONS
DECLINE TOWARDS MORNING WITH DENSE FOG DEVELOPING AS WARM AIR
MOVES OVER THE COLD SNOWPACK. IN ADDITION...-SN/FZRA IS POSSIBLE
ACROSS S NH AND PARTS OF N MA.
TODAY...MVFR/IFR CONDITIONS CONTINUE THROUGH THE DAY WITH FOG
SPREADING FARTHER NORTH INTO THE REGION. WINTRY PRECIP COMES TO AN
END SHORTLY AFTER 12Z AS TEMPERATURES WARM. HEAVY RAIN AND EVEN
SOME THUNDER IS POSSIBLE THIS AFTERNOON AHEAD OF A COLD FRONT.
LLWS IS ALSO LIKELY PARTICULARLY ACROSS RI AND SE MA AS LOW LEVEL
JET STRENGTHENS OVER THE AREA.
TONIGHT...CONDITIONS IMPROVE TO VFR AFTER MIDNIGHT.
KBOS TERMINAL...HIGH CONFIDENCE IN TAF TRENDS.
KBDL TERMINAL...HIGH CONFIDENCE IN TAF TRENDS.
OUTLOOK...SATURDAY THROUGH TUESDAY...
VFR LIKELY MUCH OF THIS TIME FRAME. BRIEF MVFR POSSIBLE SUNDAY NIGHT
IN A PERIOD OF LIGHT SNOW. MODEST WSW WIND SAT SHIFTS TO WNW SUN/MON
AND TUE.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SMALL CRAFT ADVISORIES CONTINUE FOR ALL OF THE COASTAL WATERS EXCEPT
BOSTON HARBOR. THESE ARE LARGELY FOR SEAS BUT THERE WILL BE A
PERIOD OF TIME THIS AFTERNOON AND EVENING WHEN A COLD FRONT MOVES
OVER THE WATERS AND SOUTHERLY WINDS WILL SWITCH TO WESTERLY WINDS
AND GUSTS UP TO 25-30 KTS ARE POSSIBLE. VISIBILITIES WILL BE
REDUCED AT TIMES IN RAIN AND THERE IS A LOW PROBABILITY OF THUNDER
ACCOMPANYING SOME OF THIS RAIN LATER THIS AFTERNOON AND EVENING.
OUTLOOK...SATURDAY THROUGH TUESDAY...
SAT/SUN...MODEST SW WIND SAT SHIFTS TO WNW SUNDAY. VSBY GOOD BUT MAY
LOWER IN SNOW SUNDAY NIGHT.
MON/TUE...MODEST WNW WIND ALONG WITH GOOD VSBY. FREEZING SPRAY
POSSIBLE AS ARCTIC AIR OVERSPREADS THE WATERS ON A GUSTY WNW WIND.
&&
.HYDROLOGY...
SNOW DEPTHS ACROSS MOST OF SOUTHERN NEW ENGLAND RANGE FROM 1 TO
2 FEET...EXCEPT FOR SOMEWHAT LOWER AMOUNTS ALONG SOUTH COASTAL RI
AND MA. TEMPERATURES ARE FORECAST TO CLIMB GENERALLY INTO THE 40S
TO LOW 50S FRIDAY AND SATURDAY...AND OVERNIGHT LOWS WILL BE CLOSE
TO OR BELOW FREEZING. AS A RESULT SOME SNOWMELT WILL OCCUR DURING
THE DAYTIME...WITH THE MOST SNOWMELT EXPECTED ACROSS SOUTHEAST MA
AND SOUTHERN RI WHERE THE SNOWPACK IS THE MOST DENSE AND THE
WARMEST.
RAINFALL...0.25 TO 0.35 INCHES OF RAINFALL ARE EXPECTED TODAY.
LOCALLY HIGHER AMOUNTS ARE POSSIBLE IF THUNDERSTORMS DEVELOP. THIS
WILL LIKELY CAUSE PONDING OF WATER IN LOCATIONS WHERE THERE ARE
SNOW CLOGGED DRAINS. THE HEAVIEST SHOWERS WILL LIKELY OCCUR
BETWEEN 4 PM AND 8 PM. THIS TIMING MAY IMPACT THE LATE DAY COMMUTE
WITH STREET AND HIGHWAY FLOODING.
THE COMBINATION RAIN AND SNOWMELT TODAY WILL GIVE SOME AREAS SMALL
STREAMS AND RIVERS A BOOST...AND THIS MAY PROMPT ICE MOVEMENT.
THERE IS A CHANCE OF ISOLATED ICE JAM DEVELOPMENT TODAY FOR SMALL
STREAMS ACROSS CENTRAL INTO WESTERN MA AND NORTHERN CT.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...FREEZING RAIN ADVISORY UNTIL 10 AM EST THIS MORNING FOR
MAZ002>005-008>012-026.
NH...FREEZING RAIN ADVISORY UNTIL 10 AM EST THIS MORNING FOR NHZ011-
012-015.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 AM EST SATURDAY FOR ANZ231>234-
251.
SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 1 AM EST
SATURDAY FOR ANZ236.
SMALL CRAFT ADVISORY UNTIL 7 AM EST SATURDAY FOR ANZ235-237.
SMALL CRAFT ADVISORY UNTIL 7 AM EST SATURDAY FOR ANZ250-
254>256.
&&
$$
SYNOPSIS...NOCERA/RLG
NEAR TERM...NOCERA/RLG
SHORT TERM...RLG
LONG TERM...NOCERA
AVIATION...NOCERA/RLG
MARINE...NOCERA/RLG
HYDROLOGY...
AREA FORECAST DISCUSSION
NWS ALBANY NY
621 AM EST FRI FEB 21 2014
.SYNOPSIS...
AHEAD OF A COLD FRONT...MILDER AIR WILL MOVE INTO THE REGION FOR
TODAY...ALONG WITH RAIN SHOWERS...GUSTY WINDS OVER THE HIGH
TERRAIN...AND A SLIGHT CHANCE FOR A THUNDERSTORM. AFTER THE FRONT
PASSES THROUGH THE REGION LATE TODAY...THE THREAT FOR RAIN SHOWERS
WILL END. DAYTIME TEMPERATURES WILL CONTINUE TO BE ABOVE NORMAL INTO
THE WEEKEND...BUT MUCH COLDER AIR WILL RETURN TO THE REGION FOR MUCH
OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 621 AM EST...A STRONG STORM SYSTEM AND POTENT UPPER LEVEL
SHORTWAVE IS MOVING ACROSS THE UPPER GREAT LAKES. A WARM FRONT
ASSOCIATED WITH THIS STORM IS HAVING A TOUGH TIME MOVING ACROSS
OUR REGION...DUE TO PLENTY OF LOW LEVEL COLD AIR IN PLACE THANKS
TO A DEEP SNOW PACK. TEMPERATURES CONTINUE TO BE IN THE 30S ACROSS
OUR ENTIRE REGION.
STEADY PRECIPITATION HAS MOVED NORTH AND EAST OF THE REGION...AS
THE BEST ISENTROPIC LIFT/WARM AIR ADVECTION IS NOW FOCUSED ACROSS
NORTHERN NEW ENGLAND. WITH TEMPERATURES WARMING THROUGH THE 30S
AND MOST OF THE PRECIPITATION DONE...WE/VE CANCELLED THE WINTER
WEATHER ADVISORY FOR MOST OF THE AREA. WE WILL CONTINUE IT FOR A
LITTLE LONGER FOR THE EASTERN ADIRONDACKS...LAKE GEORGE AREA...AND
SRN VT...AS SOME LIGHT PRECIPITATION REMAINS THERE...AND SOME
POCKETS OF 30-32 DEGREES ARE STILL OCCURRING ACCORDING TO MESO OBS
AT THIS TIME. ONCE TEMPS WARM UP AND PRECIP ENDS...WE SHOULD BE
ABLE TO CANCEL THE ADVISORY.
AS SHOWN IN THE MODELS...THIS BREAK IN THE PRECIP LOOKS TO
CONTINUE THROUGH MUCH OF THE MORNING HOURS. WE HAVE LOWERED POPS
TO CHC THROUGH THE MID MORNING HOURS FOR CENTRAL/SOUTHERN PARTS OF
THE AREA. HOWEVER...THE MOIST SOUTHERLY FLOW...COMBINED WITH SOME
UPSLOPE...MAY ALLOW FOR SOME SPOTTY AREAS OF LIGHT RAIN SHOWERS BY
LATER THIS MORNING...SO WE WILL RAISE POPS BACK UP TO LIKELY FOR
THE LATE MORNING HOURS. MAX TEMPS SHOULD WARM UP INTO THE LOWER TO
MID 40S FOR VALLEY AREAS...WITH UPPER 30S IN THE HIGH TERRAIN WITH
THESE HIGHS IN THE LATE MORNING TO EARLY AFTERNOON.
THE STORM/S COLD FRONT LOOKS TO MOVE FROM WEST TO EAST DURING THE
AFTERNOON HOURS. A STRONGLY FORCED LINE OF SHOWERS...AND POSSIBLY
SOME ISOLATED THUNDERSTORMS...WILL MOVE ACROSS THE AREA. THIS IS
SEEN IN THE 09Z 3KM HRRR AS WELL...WITH THE TIMING ACROSS OUR
AREA BASICALLY FROM 1 PM THROUGH 5 PM. SHOWALTER VALUES LOOK TO BE
JUST BELOW ZERO...SO SOME ELEVATED INSTABILITY IS POSSIBLE FOR A
RUMBLE OR TWO OF THUNDER...BUT NO STRONG/SEVERE STORMS ARE
ANTICIPATED DUE TO MEAGER SURFACE BASED INSTABILITY. ONCE THE
FRONT GOES THROUGH...THE THREAT FOR SHOWERS WILL DIMINISH
GREATLY...AND TEMPS WILL START TO FALL ONCE AGAIN.
WITH THE PASSAGE OF THE BOUNDARY...THERE MAY BE A FEW STRONGER GUSTS
OF WIND...ESP OVER THE HIGHER TERRAIN. THE BETTER CHANCE FOR STRONG
WINDS MAY BE BEHIND THE FRONT...AS COOLER AIR ALOFT ALLOWS FOR
BETTER MIXING.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/...
BEHIND THE COLD FRONT...COOLER AIR ALOFT WILL MOVE INTO THE
REGION AS THE STORM STORM LIFTS UP TOWARDS HUDSON BAY CANADA WITH
850 HPA TEMPS DROPPING BACK BELOW FREEZING. GUSTY W-SW WINDS WILL
BE IN PLACE FOR TONIGHT. WHILE MOST AREAS WILL STAY DRY...SOME
LINGERING CYCLONIC FLOW RAIN/SNOW SHOWERS CANNOT BE TOTALLY RULED
OUT FOR UPSLOPE FAVORED AREAS OF THE WESTERN ADIRONDACKS FOR
TONIGHT INTO SATURDAY. OTHERWISE...IT WILL REMAIN DRY. MIN TEMPS
WILL BE IN THE 20S TONIGHT. GOOD MIXING TOMORROW WILL PROMOTE A
MILD DAY...DESPITE BEING BEHIND THE COLD FRONT...WITH HIGHS
RANGING FROM THE MID TO UPPER 30S IN THE HIGH TERRAIN TO THE MID
TO UPPER 40S FOR VALLEY AREAS. TEMPS LOOK TO DROP BACK DOWN IN THE
TEENS AND 20S FOR SAT NIGHT WITH MAINLY DRY WEATHER.
THE MODELS SHOW A QUICK MOVING STORM SYSTEM AFFECTING THE REGION
AT SOME POINT BETWEEN SUNDAY AND SUNDAY NIGHT. THE TRACK AND TIMING OF
THIS SYSTEM REMAINS IN QUESTION...BUT ALL MODELS AGREE THAT ANY
QPF WOULD BE VERY LIGHT...AND IT LOOKS TO MOVE THROUGH RATHER
QUICKLY. WITH PRECIP ON THE NORTHERN SIDE OF THE SYSTEM...AND WITH
EXPECTED COLDER TEMPS ALOFT...MOST OF THE PRECIP SHOULD BE
SNOW...PERHAPS MIXING WITH A LITTLE BIT OF RAIN AT TIMES FOR
VALLEY AREAS. JUST AN INCH OR TWO OF SNOW LOOKS TO OCCUR. FOR
NOW...WILL JUST GO WITH CHC POPS FOR SUN/SUN NIGHT DUE TO
UNCERTAINTY REGARDING ITS EXACT TRACK/TIMING. MAX TEMPS WILL BE IN
THE 30S...AND MINS SUNDAY NIGHT LOOK TO BE IN THE TEENS/20S.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
MAINLY DRY AND VERY COLD CONDITIONS ARE EXPECTED FOR MUCH OF THE
LONG TERM PERIOD.
ANY CHANCES FOR PCPN WILL BE MAINLY TIED TO LAKE EFFECT DOWNWIND OF
LAKE ONTARIO ALTHOUGH A WEAK COASTAL LOW PASSES SOUTHEAST OF OUR
REGION ON TUESDAY WITH A STRONGER COASTAL LOW FOLLOWING A SIMILAR
TRACK ON WEDNESDAY. SINCE THIS SYSTEM LOOKS TO BE STRONGER AND TRACK
A LITTLE CLOSER TO OUR REGION WILL PLACE SLIGHT CHANCE POPS IN THE
GRIDS FOR NOW. IN ADDITION TO THE VERY COLD AIR IN PLACE ACRS OUR
REGION WIND CHILLS MAY REACH ADVISORY CRITERIA WEDNESDAY NIGHT AND
THURSDAY ACRS THE HIGHER TERRAIN. THIS WILL BE MENTIONED IN THE HWO.
AS FOR TEMPS EXPECT HIGHS ON MONDAY TO RANGE FROM THE UPPER TEENS
NORTHWEST TO MID 30S SOUTHEAST WITH HIGHS TUESDAY...WEDNESDAY AND
THURSDAY RANGING FROM THE MID TEENS NORTHWEST TO UPPER 20S
SOUTHEAST. LOWS MONDAY NIGHT WILL BE IN THE SINGLE DIGITS TO LOWER
TEENS WITH LOWS TUESDAY NIGHT AND WEDNESDAY NIGHT MAINLY IN THE 5
BELOW TO 10 ABOVE ZERO RANGE.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
MUCH OF THE RAIN HAS ENDED AT LEAST FOR NOW AT THE TAF SITES WITH
THE NEXT BATCH OF RAIN AHEAD OF THE COLD FRONT NOT EXPECTED TO
ARRIVE UNTIL EARLY AFTERNOON. THE TAF SITES UP UNTIL THIS TIME ARE
EXPECTED TO BE MVFR AT KGFL AND KALB WITH IFR/LIFR CONDITIONS
EXPECTED AT KPSF AND KPOU WHERE FOG AND LOW STRATUS WL BE PRESENT.
IFR CONDITIONS ARE EXPECTED AT ALL OF THE TAF SITES STARTING ARND
18Z AS THE NEXT BATCH OF RAIN MOVES IN. A COLD FRONT WL SWEEP
THROUGH THE RGN LATE THIS AFTERNOON WITH SKIES BECOMING SKC THIS
EVENING IN THE WAKE OF THE COLD FRONT.
WINDS WILL BE LIGHT AND VARIABLE UNTIL EARLY AFTERNOON AND THEN
NE-SE ARND 5 KTS AHD OF THE FRONT AND WEST TO SOUTHWEST AT 6 TO 10
KTS IN THE WAKE OF THE COLD FRONT.
OUTLOOK...
SATURDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SUNDAY-SUNDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF
SHRA...SHSN.
MONDAY-MONDAY NIGHT: LOW OPERATIONAL IMPACT. BREEZY. NO SIG WX.
TUESDAY: NO OPERATIONAL IMPACT. NO SIG WX.
TUESDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN.
&&
.HYDROLOGY...
THE SNOW DEPTH ACROSS EAST CENTRAL NEW YORK AND ADJACENT WESTERN
NEW ENGLAND ARE GENERALLY FROM 1 TO 3+ FEET.
TEMPERATURES ARE CURRENTLY IN THE LOWER TO MIDDLE 30S...WITH STEADY
RAIN AND FREEZING RAIN OCCURRING ACROSS THE NORTHERN HALF OF THE
REGION AS A WARM FRONT MOVES ACROSS THE REGION. WITH A SOUTHERLY
FLOW DEVELOPING...TEMPERATURES WILL BRIEFLY BE ABOVE NORMAL
TODAY...WITH HIGHS IN THE UPPER 30S TO MID 40S...ALONG WITH SOME
ADDITIONAL RAIN SHOWERS. HOWEVER...COLDER AIR WILL QUICKLY RETURN
BEHIND THIS AFTERNOON/S COLD FRONT...WITH TEMPERATURES DROPPING BACK
BELOW FREEZING ACROSS THE ENTIRE REGION BY TONIGHT.
STORM TOTAL QPF WILL BE A HALF INCH TO NEARLY ONE AND A HALF
INCHES...WITH THE HIGHEST AMOUNTS ACROSS THE ADIRONDACKS.
HOWEVER...THIS QPF AND EXPECTED SNOW MELT WILL HAVE A LIMITED
RESPONSE ON AREA RIVERS AND STREAMS...AS MUCH OF IT WILL BE ABSORBED
BY THE DEEP SNOWPACK. THE LATEST MMEFS...AS WELL AS FORECASTS FROM
THE NERFC...DO NOT FORECAST ANY FLOODING OVER THE NEXT DAY OR
SO...ALTHOUGH THERE WILL BE SOME RISES ON AREA RIVERS AND STREAMS.
DAYTIME TEMPERATURES OVER THE WEEKEND WILL CONTINUE TO BE ABOVE
FREEZING...AND OVERNIGHT LOWS WILL DROP BELOW FREEZING. THIS SHOULD
ALLOW FOR A STEADY CONTROLLED SNOW MELT...WHICH WILL LIMIT ANY
FLOODING CONCERNS. MUCH COLDER WEATHER...WITH TEMPERATURES
COMPLETELY BELOW FREEZING...WILL RETURN FOR MUCH OF NEXT WEEK.
WE WILL CONTINUE TO MENTION A SLIGHT CHC FOR AN ISOLATED ICE JAM ON
SMALLER STREAMS AND CREEK IN THE HWO STATEMENT FOR TODAY INTO
TONIGHT DUE TO RAIN MELT AND WARMER TEMPERATURES...BUT WIDESPREAD
FLOOD ISSUES ARE NOT ANTICIPATED AT THIS TIME.
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...WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
NYZ033-041>043-082>084.
MA...NONE.
VT...WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
VTZ013>015.
&&
$$
SYNOPSIS...FRUGIS
NEAR TERM...FRUGIS
SHORT TERM...FRUGIS
LONG TERM...11
AVIATION...11
HYDROLOGY...FRUGIS
AREA FORECAST DISCUSSION
NWS ALBANY NY
327 AM EST FRI FEB 21 2014
.SYNOPSIS...
AHEAD OF A COLD FRONT...MILDER AIR WILL MOVE INTO THE REGION FOR
TODAY...ALONG WITH RAIN SHOWERS...GUSTY WINDS OVER THE HIGH
TERRAIN...AND A SLIGHT CHANCE FOR A THUNDERSTORM. AFTER THE FRONT
PASSES THROUGH THE REGION LATE TODAY...THE THREAT FOR RAIN SHOWERS
WILL END. DAYTIME TEMPERATURES WILL CONTINUE TO BE ABOVE NORMAL INTO
THE WEEKEND...BUT MUCH COLDER AIR WILL RETURN TO THE REGION FOR MUCH
OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 327 AM EST...A STRONG STORM SYSTEM AND POTENT UPPER LEVEL
SHORTWAVE IS MOVING ACROSS THE UPPER GREAT LAKES. A WARM FRONT
ASSOCIATED WITH THIS STORM IS HAVING A TOUGH TIME MOVING ACROSS
OUR REGION...DUE TO PLENTY OF LOW LEVEL COLD AIR IN PLACE THANKS
TO A DEEP SNOW PACK. TEMPERATURES CONTINUE TO BE IN THE LOWER TO
MIDDLE 30S ACROSS THE REGION.
WITH TEMPS ALOFT WELL ABOVE FREEZING...A BAND OF STEADY RAIN AND /IN
AREAS WHERE SURFACE TEMPERATURES REMAIN BELOW FREEZING/ FREEZING
RAIN IS MOVING ACROSS THE NORTHERN HALF OF THE AREA DUE TO STRONG
ISENTROPIC LIFT/WARM AIR ADVECTION. ALTHOUGH SOME FREEZING RAIN IS
STILL OCCURRING IN SHELTERED VALLEYS OF THE ADIRONDACKS AND SRN
GREEN MOUNTAINS...SFC TEMPS WILL GRADUALLY WARM UP ABOVE FREEZING
ACROSS THE ENTIRE REGION BY THE MID MORNING HOURS. THIS WILL END THE
THREAT FOR FREEZING RAIN. UNTIL THEN...AN ADDITIONAL TRACE TO TWO
TENTHS OF AN INCH OF ICE WILL BE POSSIBLE FOR THESE ISOLATED AREAS.
MOST OTHER LOCATIONS WILL JUST SEE A PLAIN RAIN...BUT WITH TEMPS
BARELY ABOVE FREEZING...PLENTY OF SLUSH WILL REMAIN AROUND...AND
SOME SURFACES MAY STILL BE ICY OR SLIPPERY DUE TO RECENT SNOW/SLEET
FROM LAST EVENING. WINTER WEATHER ADVISORIES REMAIN IN EFFECT FOR
NORTHERN PORTIONS OF THE AREA TO ACCOUNT FOR THIS ISOLATED FREEZING
RAIN POTENTIAL...BUT SHOULD BE ABLE TO BE CANCELLED/ALLOWED TO
EXPIRE LATER THIS MORNING.
THERE LOOKS TO BE A BREAK IN THE STEADY PRECIP DURING BETWEEN ABOUT
SUNRISE AND EARLY AFTERNOON...AS SEEN IN THE 05Z 3KM HRRR AND 00Z
NAM12...AS THE BEST ISENTROPIC LIFT SHIFTS NORTHWARD AND THE STORM/S
COLD FRONT CONTINUES TO REMAIN UPSTREAM ACROSS WESTERN NY.
HOWEVER...WE WILL STILL KEEP POPS RATHER HIGH FOR THE MORNING...AS
SOME LIGHT RAIN SHOWERS OR DRIZZLE MAY BE PASSING THROUGH THE
REMAINDER DUE TO THE MOIST SOUTHERLY FLOW...ESP IN UPSLOPE FAVORED
AREAS. MAX TEMPS SHOULD WARM UP INTO THE LOWER TO MID 40S FOR VALLEY
AREAS...WITH UPPER 30S IN THE HIGH TERRAIN WITH THESE HIGHS IN THE
LATE MORNING TO EARLY AFTERNOON.
THE STORM/S COLD FRONT LOOKS TO MOVE FROM WEST TO EAST DURING THE
AFTERNOON HOURS. A STRONGLY FORCED LINE OF SHOWERS...AND POSSIBLY
SOME ISOLATED THUNDERSTORMS...WILL MOVE ACROSS THE AREA. THIS IS
SEEN IN THE 3KM HRRR AS WELL...WITH THE TIMING ACROSS OUR AREA BASICALLY
FROM 1 PM THROUGH 4 PM. SHOWALTER VALUES LOOK TO BE JUST BELOW
ZERO...SO SOME ELEVATED INSTABILITY IS POSSIBLE FOR A RUMBLE OR
TWO OF THUNDER...BUT NO STRONG/SEVERE STORMS ARE ANTICIPATED DUE
TO MEAGER SURFACE BASED INSTABILITY. ONCE THE FRONT GOES
THROUGH...THE THREAT FOR SHOWERS WILL DIMINISH GREATLY...AND TEMPS
WILL START TO FALL ONCE AGAIN.
WITH THE PASSAGE OF THE BOUNDARY...THERE MAY BE A FEW STRONGER GUSTS
OF WIND...ESP OVER THE HIGHER TERRAIN. THE BETTER CHANCE FOR STRONG
WINDS MAY BE BEHIND THE FRONT...AS COOLER AIR ALOFT ALLOWS FOR
BETTER MIXING.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/...
BEHIND THE COLD FRONT...COOLER AIR ALOFT WILL MOVE INTO THE
REGION AS THE STORM STORM LIFTS UP TOWARDS HUDSON BAY CANADA WITH
850 HPA TEMPS DROPPING BACK BELOW FREEZING. GUSTY W-SW WINDS WILL
BE IN PLACE FOR TONIGHT. WHILE MOST AREAS WILL STAY DRY...SOME
LINGERING CYCLONIC FLOW RAIN/SNOW SHOWERS CANNOT BE TOTALLY RULED
OUT FOR UPSLOPE FAVORED AREAS OF THE WESTERN ADIRONDACKS FOR
TONIGHT INTO SATURDAY. OTHERWISE...IT WILL REMAIN DRY. MIN TEMPS
WILL BE IN THE 20S TONIGHT. GOOD MIXING TOMORROW WILL PROMOTE A
MILD DAY...DESPITE BEING BEHIND THE COLD FRONT...WITH HIGHS
RANGING FROM THE MID TO UPPER 30S IN THE HIGH TERRAIN TO THE MID
TO UPPER 40S FOR VALLEY AREAS. TEMPS LOOK TO DROP BACK DOWN IN THE
TEENS AND 20S FOR SAT NIGHT WITH MAINLY DRY WEATHER.
THE MODELS SHOW A QUICK MOVING STORM SYSTEM AFFECTING THE REGION
AT SOME POINT BETWEEN SUNDAY AND SUNDAY NIGHT. THE TRACK AND TIMING OF
THIS SYSTEM REMAINS IN QUESTION...BUT ALL MODELS AGREE THAT ANY
QPF WOULD BE VERY LIGHT...AND IT LOOKS TO MOVE THROUGH RATHER
QUICKLY. WITH PRECIP ON THE NORTHERN SIDE OF THE SYSTEM...AND WITH
EXPECTED COLDER TEMPS ALOFT...MOST OF THE PRECIP SHOULD BE
SNOW...PERHAPS MIXING WITH A LITTLE BIT OF RAIN AT TIMES FOR
VALLEY AREAS. JUST AN INCH OR TWO OF SNOW LOOKS TO OCCUR. FOR
NOW...WILL JUST GO WITH CHC POPS FOR SUN/SUN NIGHT DUE TO
UNCERTAINTY REGARDING ITS EXACT TRACK/TIMING. MAX TEMPS WILL BE IN
THE 30S...AND MINS SUNDAY NIGHT LOOK TO BE IN THE TEENS/20S.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
MAINLY DRY AND VERY COLD CONDITIONS ARE EXPECTED FOR MUCH OF THE
LONG TERM PERIOD.
ANY CHANCES FOR PCPN WILL BE MAINLY TIED TO LAKE EFFECT DOWNWIND OF
LAKE ONTARIO ALTHOUGH A WEAK COASTAL LOW PASSES SOUTHEAST OF OUR
REGION ON TUESDAY WITH A STRONGER COASTAL LOW FOLLOWING A SIMILAR
TRACK ON WEDNESDAY. SINCE THIS SYSTEM LOOKS TO BE STRONGER AND TRACK
A LITTLE CLOSER TO OUR REGION WILL PLACE SLIGHT CHANCE POPS IN THE
GRIDS FOR NOW. IN ADDITION TO THE VERY COLD AIR IN PLACE ACRS OUR
REGION WIND CHILLS MAY REACH ADVISORY CRITERIA WEDNESDAY NIGHT AND
THURSDAY ACRS THE HIGHER TERRAIN. THIS WILL BE MENTIONED IN THE HWO.
AS FOR TEMPS EXPECT HIGHS ON MONDAY TO RANGE FROM THE UPPER TEENS
NORTHWEST TO MID 30S SOUTHEAST WITH HIGHS TUESDAY...WEDNESDAY AND
THURSDAY RANGING FROM THE MID TEENS NORTHWEST TO UPPER 20S
SOUTHEAST. LOWS MONDAY NIGHT WILL BE IN THE SINGLE DIGITS TO LOWER
TEENS WITH LOWS TUESDAY NIGHT AND WEDNESDAY NIGHT MAINLY IN THE 5
BELOW TO 10 ABOVE ZERO RANGE.
&&
.AVIATION /08Z FRIDAY THROUGH TUESDAY/...
THE NEXT BATCH OF PCPN IS MOVING QUICKLY EAST INTO THE HUDSON VALLEY
AT THIS HOUR. MOST OF THE PCPN WILL BE IN THE FORM OF RAIN WITH
POCKETS OF SLEET. THIS WILL RESULT IN MVFR/IFR CONDITIONS FOR MUCH
OF THE TAF PERIOD. FRIDAY DURING THE DAY THE PCPN TYPE SHOULD BE ALL
RAIN. SOLID IFR/LIFR EXPECTED THROUGH MUCH OF THE DAY ON FRIDAY
MORNING DUE TO RELATIVELY WARM/MOIST AIR MOVING OVER A DEEP
SNOWPACK. RAIN WILL CONTINUE THROUGH MUCH OF FRIDAY BEFORE A COLD
FRONT PASSES THROUGH DURING THE AFTERNOON.
WINDS WILL BE SOUTH-SOUTHEAST AROUND 4-8 KT...BECOMING LIGHT AND
VARIABLE OVERNIGHT INTO FRIDAY MORNING. WINDS WILL SHIFT TO
SOUTHWEST AND WEST LATER FRIDAY AFTERNOON AT 10 KT OR LESS.
OUTLOOK...
SATURDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SUNDAY-SUNDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF
SHRA...SHSN.
MONDAY-MONDAY NIGHT: LOW OPERATIONAL IMPACT. BREEZY. NO SIG WX.
TUESDAY: NO OPERATIONAL IMPACT. NO SIG WX.
TUESDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN.
&&
.HYDROLOGY...
THE SNOW DEPTH ACROSS EAST CENTRAL NEW YORK AND ADJACENT WESTERN
NEW ENGLAND ARE GENERALLY FROM 1 TO 3+ FEET.
TEMPERATURES ARE CURRENTLY IN THE LOWER TO MIDDLE 30S...WITH STEADY
RAIN AND FREEZING RAIN OCCURRING ACROSS THE NORTHERN HALF OF THE
REGION AS A WARM FRONT MOVES ACROSS THE REGION. WITH A SOUTHERLY
FLOW DEVELOPING...TEMPERATURES WILL BRIEFLY BE ABOVE NORMAL
TODAY...WITH HIGHS IN THE UPPER 30S TO MID 40S...ALONG WITH SOME
ADDITIONAL RAIN SHOWERS. HOWEVER...COLDER AIR WILL QUICKLY RETURN
BEHIND THIS AFTERNOON/S COLD FRONT...WITH TEMPERATURES DROPPING BACK
BELOW FREEZING ACROSS THE ENTIRE REGION BY TONIGHT.
STORM TOTAL QPF WILL BE A HALF INCH TO NEARLY ONE AND A HALF
INCHES...WITH THE HIGHEST AMOUNTS ACROSS THE ADIRONDACKS.
HOWEVER...THIS QPF AND EXPECTED SNOW MELT WILL HAVE A LIMITED
RESPONSE ON AREA RIVERS AND STREAMS...AS MUCH OF IT WILL BE ABSORBED
BY THE DEEP SNOWPACK. THE LATEST MMEFS...AS WELL AS FORECASTS FROM
THE NERFC...DO NOT FORECAST ANY FLOODING OVER THE NEXT DAY OR
SO...ALTHOUGH THERE WILL BE SOME RISES ON AREA RIVERS AND STREAMS.
DAYTIME TEMPERATURES OVER THE WEEKEND WILL CONTINUE TO BE ABOVE
FREEZING...AND OVERNIGHT LOWS WILL DROP BELOW FREEZING. THIS SHOULD
ALLOW FOR A STEADY CONTROLLED SNOW MELT...WHICH WILL LIMIT ANY
FLOODING CONCERNS. MUCH COLDER WEATHER...WITH TEMPERATURES
COMPLETELY BELOW FREEZING...WILL RETURN FOR MUCH OF NEXT WEEK.
WE WILL CONTINUE TO MENTION A SLIGHT CHC FOR AN ISOLATED ICE JAM ON
SMALLER STREAMS AND CREEK IN THE HWO STATEMENT FOR TODAY INTO
TONIGHT DUE TO RAIN MELT AND WARMER TEMPERATURES...BUT WIDESPREAD
FLOOD ISSUES ARE NOT ANTICIPATED AT THIS TIME.
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...WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
NYZ033-039>043-048>050-082>084.
WINTER WEATHER ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR
NYZ032-038-047-051>054.
MA...WINTER WEATHER ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR
MAZ001-025.
VT...WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
VTZ013>015.
&&
$$
SYNOPSIS...FRUGIS
NEAR TERM...FRUGIS
SHORT TERM...FRUGIS
LONG TERM...11
AVIATION...11
HYDROLOGY...FRUGIS
AREA FORECAST DISCUSSION...UPDATED
NWS PEACHTREE CITY GA
110 PM EST FRI FEB 21 2014
UPDATE...
A LINE OF SHOWERS AND TSTMS FROM SWAINSBORO TO LUMBER CITY
CONTINUES MOVING EAST THROUGH THE REMAINDER OF THE FFC FORECAST
AREA. MOST OF THE FFC GA COUNTIES HAVE BEEN REMOVED FROM THE
SVR TSTM WATCH 22. THE REMAINING THREE COUNTIES WILL BE REMOVED
BY 1100 PM EST. THE COLD FRONT EXTENDING FROM WARRENTON TO CORDELE
WILL EXIT THE FORECAST AREA BY EARLY AFTERNOON. RAPID CLEARING
WILL CONTINUE ACROSS NORTH AND CENTRAL GEORGIA THROUGH THE DAY.
16
PREV DISCUSSION... /ISSUED 650 AM EST FRI FEB 21 2014/
PREV DISCUSSION... /ISSUED 504 AM EST FRI FEB 21 2014/
UPDATE...
AFD UPDATE TO REFRESH FFC WATCH/WARNING/ADVISORY SECTION BELOW.
PREV DISCUSSION... /ISSUED 322 AM EST FRI FEB 21 2014/
SHORT TERM /TODAY THROUGH SATURDAY/...
MAIN FORECAST CONCERN THROUGH THE SHORT TERM CONTINUES TO BE THE
COLD FRONT PUSHING INTO NORTHWEST GEORGIA THIS MORNING. OVERALL
MODELS STILL CONSISTENT WITH THE TIMING OF THE SYSTEM THROUGH THE
AREA...AND FORECAST IS SKEWED TOWARDS HRRR AND LOCAL WRF FOR TIMING
OF THE FRONT PUSHING OUT OF THE CWA. ANTICIPATE THE BULK OF THE
ACTIVITY TO BE THROUGH THE ATL AREA 08-11Z...AND THROUGH THE MCN
AREA BY 11-13Z.
SEVERE POTENTIAL ENOUGH TO ISSUE SVR TSTM WATCH THROUGH SUNRISE. NAM
CONTINUES TO ADVERTISE THE HIGHER MUCAPE VALUES...WITH THE GFS STILL
AROUND 300-400J/KG AND MODELED LOW LEVEL SHEAR STILL IN THE 45-50KT
RANGE. OVERALL THE TORNADO THREAT IS MARGINAL AND IS EXPECTED
GRADUALLY LESSON THROUGH THE EARLY MORNING HOURS. THAT BEING
SAID...AN ISOLATED TORNADO CAN NOT BE RULED OUT ENTIRELY. A TORNADO
WATCH CONTINUES THROUGH 10Z FOR NORTHERN PORTIONS OF THE CWA. THE
MAIN CONCERN CONTINUES TO BE THE DAMAGING WINDS ASSOCIATED WITH THE
LINE GIVEN THE SUFFICIENT WIND SHEAR AND INSTABILITY. SOME ROTATION
HAS BEEN NOTED /ALBEIT BROAD/ IN THESE STORMS AS THEY HAVE MOVED
INTO THE STATE.
AS THE STORMS MOVE THROUGH...THE THREAT OF SEVERE ACTIVITY DROPS OFF
QUICKLY. LIGHT RAIN SHOWERS WILL PERSIST BEHIND THE MAIN LINE FOR A
FEW HOURS BEFORE CLEARING BEGINS.
WINDS ASSOCIATED WITH THE LINE WILL ALSO DIMINISH INTO THE DAYLIGHT
HOURS. GUSTY WINDS AHEAD OF THE FRONT AND THE DAMAGING WINDS
EMBEDDED WITHIN THE CONVECTION COULD BRING DOWN ALREADY WEAKENED
TREES ESPECIALLY VULNERABLE FROM THE RECENT ICE STORM.
QPF OF 1-1.25 INCHES WITH LOCALLY HIGHER AMOUNTS ACROSS NORTHWEST
GEORGIA COULD RESULT IN QUICKLY RISING CREEKS AND RIVERS.
BEHIND THE FRONT...HIGH PRESSURE BUILDING INTO THE REGION WILL KEEP
THE REMAINDER OF THE SHORT TERM DRY. LOOKING FOR HIGHS IN THE 60S
FRIDAY AND SATURDAY...WITH LOWS IN THE 30S SATURDAY MORNING.
31
LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
THE OVERALL ACTIVE PATTERN CONTINUES INTO THE EXTENDED PERIOD. MODELS
CONTINUE TO SHOW NEARLY ZONAL FLOW ACROSS THE AREA INTO THE LONG
TERM. A WEAK UPPER LEVEL DISTURBANCE WITHIN THIS ZONAL FLOW
INTERACTS WITH AN OLD FRONTAL BOUNDARY ACROSS THE SOUTHERN PORTION
OF THE STATE. AS A RESULT...HAVE CONTINUED WITH THE SLIGHT CHANCE
TO CHANCE POPS SUNDAY...WITH THE BEST CHANCES FARTHER SOUTH. A
REINFORCING COLD FRONT PUSHES ACROSS THE AREA SUNDAY NIGHT INTO
MONDAY...WITH A DRY AND COOLER AIR MASS RETURNING TO THE STATE
MONDAY. BY MID WEEK...WEAK FRONTAL BOUNDARY MEANDERING ACROSS THE
STATE INTERACTS WITH THE FLOW ALOFT...BUT MODEL UNCERTAINTY STILL
HIGH ENOUGH TO JUST CONTINUE WITH SLIGHT CHANCES OF SHOWERS. WITH
LIMITED INSTABILITY AND WIND SHEAR...HAVE CONTINUED TO LEAVE OUT
MENTION OF THUNDERSTORMS AT THIS TIME.
39
&&
AVIATION...
18Z UPDATE...
SMALL AREA OF IFR/MVFR CEILINGS IN THE SOUTHEAST CORNER OF THE
FORECAST AREA AT THIS TIME...WELL SOUTHEAST OF THE TAF SITES...WILL
IMPROVE TO VFR BY 20Z WITH VFR CONDITIONS EXPECTED AREAWIDE THROUGH
THE REMAINDER OF THIS FORECAST PERIOD. COLD FRONT HAS CLEARED THE
FORECAST AREA WITH NORTHWEST WINDS EXPECTED TO CONTINUE AREAWIDE
THROUGH 12-15Z SATURDAY...BECOMING NORTHEASTERLY AND EVENTUALLY
SOUTHEASTERLY 15-00Z. WIND SPEEDS REMAIN 8-14KTS CURRENTLY WITH
FREQUENT GUSTS 15-23KT BUT WILL CONTINUE TO DIMINISH...DROPPING TO
6-8KT BY 00Z AND 2-5KT BY 00Z. WIND SPEEDS WILL INCREASE AFTER 12Z
SATURDAY...REACHING 4-8KT BY 18Z.
ATL CONFIDENCE...18Z UPDATE...
HIGH.
20
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 62 36 68 40 / 50 5 5 10
ATLANTA 61 39 66 43 / 10 5 5 10
BLAIRSVILLE 57 32 63 36 / 10 5 5 10
CARTERSVILLE 59 32 66 38 / 5 5 5 10
COLUMBUS 63 39 67 41 / 10 5 5 20
GAINESVILLE 61 38 65 40 / 10 5 5 10
MACON 65 34 68 40 / 60 5 5 10
ROME 59 31 65 36 / 5 5 5 10
PEACHTREE CITY 61 30 66 36 / 10 5 5 10
VIDALIA 70 45 70 46 / 100 10 5 10
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
SEVERE THUNDERSTORM WATCH UNTIL 2 PM EST THIS AFTERNOON FOR THE
FOLLOWING ZONES: EMANUEL...MONTGOMERY...TOOMBS.
&&
$$
SHORT TERM...20
LONG TERM....16
AVIATION...20
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
1026 AM EST FRI FEB 21 2014
UPDATE...
A LINE OF SHOWERS AND TSTMS FROM SWAINSBORO TO LUMBER CITY
CONTINUES MOVING EAST THROUGH THE REMAINDER OF THE FFC FORECAST
AREA. MOST OF THE FFC GA COUNTIES HAVE BEEN REMOVED FROM THE
SVR TSTM WATCH 22. THE REMAINING THREE COUNTIES WILL BE REMOVED
BY 1100 PM EST. THE COLD FRONT EXTENDING FROM WARRENTON TO CORDELE
WILL EXIT THE FORECAST AREA BY EARLY AFTERNOON. RAPID CLEARING
WILL CONTINUE ACROSS NORTH AND CENTRAL GEORGIA THROUGH THE DAY.
16
PREV DISCUSSION... /ISSUED 650 AM EST FRI FEB 21 2014/
PREV DISCUSSION... /ISSUED 504 AM EST FRI FEB 21 2014/
UPDATE...
AFD UPDATE TO REFRESH FFC WATCH/WARNING/ADVISORY SECTION BELOW.
PREV DISCUSSION... /ISSUED 322 AM EST FRI FEB 21 2014/
SHORT TERM /TODAY THROUGH SATURDAY/...
MAIN FORECAST CONCERN THROUGH THE SHORT TERM CONTINUES TO BE THE
COLD FRONT PUSHING INTO NORTHWEST GEORGIA THIS MORNING. OVERALL
MODELS STILL CONSISTENT WITH THE TIMING OF THE SYSTEM THROUGH THE
AREA...AND FORECAST IS SKEWED TOWARDS HRRR AND LOCAL WRF FOR TIMING
OF THE FRONT PUSHING OUT OF THE CWA. ANTICIPATE THE BULK OF THE
ACTIVITY TO BE THROUGH THE ATL AREA 08-11Z...AND THROUGH THE MCN
AREA BY 11-13Z.
SEVERE POTENTIAL ENOUGH TO ISSUE SVR TSTM WATCH THROUGH SUNRISE. NAM
CONTINUES TO ADVERTISE THE HIGHER MUCAPE VALUES...WITH THE GFS STILL
AROUND 300-400J/KG AND MODELED LOW LEVEL SHEAR STILL IN THE 45-50KT
RANGE. OVERALL THE TORNADO THREAT IS MARGINAL AND IS EXPECTED
GRADUALLY LESSON THROUGH THE EARLY MORNING HOURS. THAT BEING
SAID...AN ISOLATED TORNADO CAN NOT BE RULED OUT ENTIRELY. A TORNADO
WATCH CONTINUES THROUGH 10Z FOR NORTHERN PORTIONS OF THE CWA. THE
MAIN CONCERN CONTINUES TO BE THE DAMAGING WINDS ASSOCIATED WITH THE
LINE GIVEN THE SUFFICIENT WIND SHEAR AND INSTABILITY. SOME ROTATION
HAS BEEN NOTED /ALBEIT BROAD/ IN THESE STORMS AS THEY HAVE MOVED
INTO THE STATE.
AS THE STORMS MOVE THROUGH...THE THREAT OF SEVERE ACTIVITY DROPS OFF
QUICKLY. LIGHT RAIN SHOWERS WILL PERSIST BEHIND THE MAIN LINE FOR A FEW
HOURS BEFORE CLEARING BEGINS.
WINDS ASSOCIATED WITH THE LINE WILL ALSO DIMINISH INTO THE DAYLIGHT
HOURS. GUSTY WINDS AHEAD OF THE FRONT AND THE DAMAGING WINDS
EMBEDDED WITHIN THE CONVECTION COULD BRING DOWN ALREADY WEAKENED
TREES ESPECIALLY VULNERABLE FROM THE RECENT ICE STORM.
QPF OF 1-1.25 INCHES WITH LOCALLY HIGHER AMOUNTS ACROSS NORTHWEST
GEORGIA COULD RESULT IN QUICKLY RISING CREEKS AND RIVERS.
BEHIND THE FRONT...HIGH PRESSURE BUILDING INTO THE REGION WILL KEEP
THE REMAINDER OF THE SHORT TERM DRY. LOOKING FOR HIGHS IN THE 60S
FRIDAY AND SATURDAY...WITH LOWS IN THE 30S SATURDAY MORNING.
31
LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
THE OVERALL ACTIVE PATTERN CONTINUES INTO THE EXTENDED PERIOD. MODELS
CONTINUE TO SHOW NEARLY ZONAL FLOW ACROSS THE AREA INTO THE LONG
TERM. A WEAK UPPER LEVEL DISTURBANCE WITHIN THIS ZONAL FLOW
INTERACTS WITH AN OLD FRONTAL BOUNDARY ACROSS THE SOUTHERN PORTION
OF THE STATE. AS A RESULT...HAVE CONTINUED WITH THE SLIGHT CHANCE
TO CHANCE POPS SUNDAY...WITH THE BEST CHANCES FARTHER SOUTH. A
REINFORCING COLD FRONT PUSHES ACROSS THE AREA SUNDAY NIGHT INTO
MONDAY...WITH A DRY AND COOLER AIR MASS RETURNING TO THE STATE
MONDAY. BY MID WEEK...WEAK FRONTAL BOUNDARY MEANDERING ACROSS THE
STATE INTERACTS WITH THE FLOW ALOFT...BUT MODEL UNCERTAINTY STILL
HIGH ENOUGH TO JUST CONTINUE WITH SLIGHT CHANCES OF SHOWERS. WITH
LIMITED INSTABILITY AND WIND SHEAR...HAVE CONTINUED TO LEAVE OUT
MENTION OF THUNDERSTORMS AT THIS TIME.
39
AVIATION...
12Z UPDATE...
AREA OF SHOWERS AND THUNDERSTORMS HAS ALMOST PUSHED EAST OF THE
ATL METRO TAF SITES. EXPECT IT TO CLEAR THE AHN...CSG...AND MCN
AREAS BY 14Z. GUSTY NW WINDS WILL CONTINUE THROUGH MID
MORNING...THEN EXPECT SUSTAINED 8-12KT. WINDS DIMINISH OVERNIGHT.
VFR CONDITIONS BY THE AFTERNOON.
ATL CONFIDENCE...12Z UPDATE... LOW CONFIDENCE ON CIGS THROUGH
14Z...OTHERWISE HIGH CONFIDENCE.
31
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 62 36 68 40 / 50 5 5 10
ATLANTA 61 39 66 43 / 10 5 5 10
BLAIRSVILLE 57 32 63 36 / 10 5 5 10
CARTERSVILLE 59 32 66 38 / 5 5 5 10
COLUMBUS 63 39 67 41 / 10 5 5 20
GAINESVILLE 61 38 65 40 / 10 5 5 10
MACON 65 34 68 40 / 60 5 5 10
ROME 59 31 65 36 / 5 5 5 10
PEACHTREE CITY 61 30 66 36 / 10 5 5 10
VIDALIA 70 45 70 46 / 100 10 5 10
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
SEVERE THUNDERSTORM WATCH UNTIL 2 PM EST THIS AFTERNOON FOR THE
FOLLOWING ZONES: EMANUEL...MONTGOMERY...TOOMBS.
&&
$$
SHORT TERM...20
LONG TERM....16
AVIATION...20
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
1006 AM EST FRI FEB 21 2014
.SYNOPSIS...
HIGH PRESSURE WILL RETREAT EASTWARD TONIGHT IN ADVANCE OF AN APPROACHING
COLD FRONT. THE COLD FRONT WILL SWEEP THROUGH THE AREA ON
FRIDAY...STALLING JUST OFFSHORE UNTIL STRONGER HIGH PRESSURE
BUILDS INTO THE AREA ON MONDAY. A LOW PRESSURE SYSTEM COULD
DEVELOP OFF THE SOUTHEAST COAST LATE TUESDAY INTO WEDNESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
MORNING UPDATE...THE LINE OF THUNDERSTORMS HAS MOVED INTO THE FAR
INLAND COUNTIES. WARNINGS WILL BE ISSUED WITH MORE CAUTION SINCE
A LOT OF AREAS ARE MORE SUSCEPTIBLE TO WIND DAMAGE FROM THE RECENT
ICE STORM. RECENT TRENDS HAVE SHOWN A DECREASE IN LIGHTNING AS
PRECIPITABLE ECHOES ARE HOVERING NEAR OR BELOW 20K FT. SPC RUC
MESOANALYSIS INDICATES THAT CAPE VALUES ARE RANGING FROM 100 TO
500 J/KG...SO INSTABILITY IS STILL SOMEWHAT LACKING RIGHT NOW.
EXPECT THAT TO CHANGE AS THE DAY GOES ON AS SURFACE HEATING AND
FORCING INCREASES. UNTIL THEN...THE MAIN THREAT WILL BE STRONG TO
SEVERE WINDS AND ISOLATED TORNADOES. DAMAGE WAS CONFIRMED NEAR
DUBLIN IN LAURENS COUNTY WEST OF US. 6KM SHEAR WILL HOLD STEADY AT
NEARLY 45KTS...SO WE COULD SEE SOME BOWING SEGMENTS. IN TERMS OF
TIMING...ROUGH ESTIMATES ARE THAT THE LINE WILL BE NEAR SAV AT 16Z
AND CHS BY 17Z. MOST AREAS COULD SEE CLOSE TO 1.5 INCHES OF RAIN
ACCUMULATION WITH THE MORE INTENSE CELLS. TEMPERATURES WILL HOLD
STEADY IN THE LOW 70S TODAY FOR AREAS AHEAD OF THE COLD FRONT.
WITH FROPA...TEMPS COULD DROP 10 DEGREES.
PREVIOUS DISCUSSION...A STRONG MID LEVEL SHORT WAVE RIDING BELOW THE
LARGE/DEEP CLOSED UPPER LOW OVER THE GREAT LAKES WAS IMPRESSIVE
EARLY THIS MORNING ON WATER VAPOR SATELLITE IMAGERY. THIS FEATURE
WILL DIG THE MEAN UPPER TROUGH THROUGH THE TENNESSEE/OHIO VALLEYS
THIS MORNING THEN LIFT TOWARD NEW ENGLAND LATE TODAY. SUBTLE
NEGATIVE TILTING APPEARS TO BE STRONGER OFF TO THE NORTH OF OUR
FORECAST AREA THROUGH MID AFTERNOON.
ONGOING TRENDS THIS MORNING HAVE INCREASED OUR CONCERNS FOR SEVERE
WEATHER POTENTIAL IN THE PRE-FRONTAL ENVIRONMENT THROUGH MID
AFTERNOON. THE FIRST...OBVIOUSLY THE MUCH WARMER THAN GUIDANCE
READINGS THAT HAVE BECOME ROOTED ACROSS SE GEORGIA AND EASTERN SOUTH
CAROLINA EARLY THIS MORNING BEFORE DAYBREAK. ALTHOUGH TIMING OF
THE CONVECTIVE LINE THROUGH THE FORECAST AREA REMAINS FAIRLY
CONSISTENT FROM PREVIOUS MODEL RUNS TODAY...IT IS NOT GOING TO
TAKE MUCH TO ALLOW TEMPS TO RISE WARMER INTO THE LOWER TO MID 70S
THIS MORNING. UPSTREAM CONVECTION OVERNIGHT HAS BEEN QUITE
ROBUST WITH THE LATEST RAP SHOWING SURFACE BASED INSTABILITY INTO SW
GEORGIA WITH SBCAPES OVER 750 J/KG AT 08Z. SOME OF FORECAST AREAS
COULD SEE SOME THINNER CLOUDS THROUGH MID MORNING AS DENSE CLOUD
COVER WILL BE COMING IN LATER IN THE MORNING.
SPC HAS OUR REGION IN A SLIGHT RISK OF SEVERE CONVECTION AND THERE
APPEARS TO BE NO REASON TO DOUBT IT PER LATEST MESOSCALE TRENDS.
00Z HIGH RESOLUTION GUIDANCE INDICATING POTENTIAL FOR HIGHER DBZ CORES
AND LINEAR ORGANIZATION. GIVEN THE STRONG WIND FIELDS...SMALL BOWS
WOULD BE A CONCERN ALONG WITH POSSIBLE FORMATION OF A DECENT REAR
INFLOW JET. CONCERN FALLS OVER OUR NW TIER OF ZONES THAT SUFFERED
GREAT TIMBER DAMAGE FROM THE RECENT ICE STORM. TSTM GUST IMPACTS
COULD CERTAINLY BE MUCH GREATER IN THOSE ZONES WHERE WEAK AND
BROKEN LIMBS ALREADY LACE THAT REGION. EVEN A MARGINALLY GUSTY
SQUALL LINE COULD MAKE FOR SOME BAD TIMES IN SOME AREAS AND WE
WILL REMAIN COGNIZANT OF THIS SITUATION. WE WILL RAMP UP SEVERE
WORDING A BIT IN OUR HAZARDOUS WEATHER OUTLOOK THIS MORNING
ALTHOUGH IT IS STILL MORE LIKELY THAT WE ONLY SEE ONLY SEE
ISOLATED OCCURRENCES OF 50 KT CONVECTIVE WIND GUSTS IN THE
CONVECTIVE SEGMENTS/LINES AS TIMING AND STRENGTH OF DYNAMICS DO
NOT APPEAR TO COMPLETELY COME IN SYNC FOR A MORE WIDESPREAD
EVENT.
THE COLD FRONT WILL RACE THROUGH THE FORECAST AREA THIS AFTERNOON AND
OFFSHORE BY EARLY EVENING. MUCH COOLER TEMPS EXPECTED TONIGHT WITH
LOWS IN THE 40S AND GRADUALLY CLEARING SKIES.
&&
.SHORT TERM /SATURDAY THROUGH MONDAY/...
DRY HIGH PRESSURE WILL SETTLE OVER THE REGION ON SATURDAY. AMPLE
MOISTURE WITHIN A 105 KT JET OVER THE DEEP SOUTH WILL PRODUCE
EXTENSIVE CIRRUS WHICH WILL SLIGHTLY LIMIT INSOLATION. HOWEVER HIGH
TEMPS WILL STILL REACH 70F IN MANY SPOTS.
ON SUNDAY WE START TO SEE SOME CHANNELED VORTICITY ENERGY MOVE INTO
THE EASTERN UNITED STATES. MEANWHILE THE LOW-LEVEL RIDGE OVER THE
WESTERN ATLANTIC STARTS TO SHIFT EAST AS THE FLOW BACKS TO
SOUTHWESTERLY. AS LOW-LEVEL MOISTURE INCREASES...WEAK ISENTROPIC
ASCENT WILL DEVELOP ACROSS SOUTHEAST GA WITH SOME RAIN SHOWERS
POSSIBLE BY SUNDAY AFTERNOON. WE ADDED A SLIGHT CHANCE OF TSTMS
ACROSS FAR SOUTHERN AREAS BECAUSE A POCKET OF ELEVATED INSTABILITY
SHIFTS THROUGH DURING THIS TIME. LOW-LEVEL WARM ADVECTION WILL PUSH
HIGH TEMPS INTO THE LOWER TO MIDDLE 70S.
A BACKDOOR COLD FRONT WILL DROP INTO THE AREA SUNDAY NIGHT AND PUSH
OFFSHORE ON MONDAY. UPPER DYNAMICS ARE NOT VERY IMPRESSIVE
ACCOMPANYING THE FROPA SO WE ONLY HAVE 20-40 POPS SUNDAY NIGHT.
ON MONDAY...SLIGHTLY COOLER HIGH PRESSURE WILL BUILD IN FROM THE
NORTH WHILE THE BACKDOOR FRONT SITS JUST SOUTH OF THE AREA.
EXTENSIVE CLOUD COVER WILL ALSO PERSIST THOUGH THE BEST RAIN CHANCES
WILL BE FAR SOUTH CLOSER TO THE FRONT. WE SHOW HIGH TEMPS IN THE
MID/UPPER 60S.
&&
.LONG TERM /MONDAY NIGHT THROUGH THURSDAY/...
THE LONG TERM PATTERN WILL MAINLY BE DOMINATED BY A LOBE OF THE
POLAR VORTEX MOVING INTO THE GREAT LAKES REGION LATE WEEK. MONDAY
NIGHT THROUGH WEDNESDAY THE UPPER PATTERN WILL BE TRENDING TOWARD A
BROAD TROUGH REGIME WITH A SERIES OF WEAK FRONTS AND LOW PRESSURE
WAVES AFFECTING THE FORECAST AREA. DUE TO LARGE UNCERTAINTIES IN
TIMING INDIVIDUAL FEATURES WE MAINTAINED A CONSERVATIVE FORECAST
WITH MAINLY SLIGHT CHANCES FOR SHOWERS AND HIGH TEMPS IN THE 60S.
A STRONG COLD FRONT WILL SWEEP THROUGH WEDNESDAY NIGHT... FOLLOWED
BY COOL CANADIAN HIGH PRESSURE THURSDAY AND FRIDAY. THIS WILL BRING
DRY CONDITIONS AND BELOW-NORMAL TEMPERATURES.
&&
.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
PRIOR TO THE RAINS TODAY...GUSTY SW SURFACE WINDS AHEAD OF THE
SQUALL LINE ALONG WITH FAIRLY WIDESPREAD MVFR CIGS. THERE COULD BE
A BRIEF BOUT OF IFR CIGS BUT THE WINDOW LOOKS FAIRLY BRIEF. ADDED
THUNDER TO THE TAFS WITH THE LINE EXPECTED TO BE OVER KSAV AROUND
16Z AND KCHS AT 17Z. THERE IS NOT A LOT OF LIGHTNING WITH THIS
LINE...BUT THAT COULD CHANGE AS INSTABILITY INCREASES. SKIES WILL
BEGIN TO CLEAR OUT THIS EVENING WITH VFR CONDITIONS EXPECTED
TONIGHT IN THE WAKE OF A COLD FRONT.
EXTENDED AVIATION OUTLOOK...MVFR CEILINGS POSSIBLE AT KSAV SATURDAY
NIGHT AND AT BOTH TERMINALS SUNDAY NIGHT INTO MONDAY MORNING.
OTHERWISE VFR.
&&
.MARINE...
A SEVERE TSTM WATCH IS IN EFFECT FOR NEAR SHORE WATERS AND THE
CHARLESTON HARBOR.
OTHERWISE...NOT MUCH MIXING GOING ON OVER CHILLY SHELF WATERS AND IT
IS INTERESTING TO SEE WINDS GUSTS TO 20 KT AT TIMES AT CHARLESTON
AND SAVANNAH WHERE TEMPS HAVE WARMED TO THE UPPER 60S. TEMPS AT
GRAYS REEF NEAR 60 AND WINDS BELOW 10 KT ALL NIGHT WITH 2-3 FT
SEAS...QUITE THE STRONG MARINE INVERSION. SEAS WILL CONTINUE TO BUILD
OFFSHORE AND MAINTAINED A MARGINAL SCA FOR CHARLESTON COUNTY
WATERS MAINLY WELL EAST OF BULLS BAY. MOST NEAR SHORE WATERS TODAY
WILL SEE SW WINDS 15 KT OR SO AND SEAS 3-4 FT TOPS. THERE IS ALSO
A SCA FOR OUR OUTER GEORGIA WATERS WITH OCCASIONALLY GUSTY SW FLOW
AND SEAS 4-7 FT...HIGHEST NEAR THE WEST WALL OF THE GULF STREAM.
THE FRONT MOVES THROUGH THIS EVENING WITH WINDS SHIFTING W OR WNW
TONIGHT WITH COLD AIR ADVECTION MORE GRADUAL THAN SHARP...CONDITIONS
BELOW SCA CRITERIA.
MARINE WINDS/SEAS WILL BE RATHER LIGHT SATURDAY THROUGH SUNDAY
BEFORE A COLD FRONT DROPS INTO THE WATER SUNDAY NIGHT. WINDS WILL
INCREASE ALONG THE FRONT BUT THE STRONGER SURGE COMES MONDAY AS THE
FLOW BECOMES NE. CONDITIONS COULD FLIRT WITH ADVISORY LEVELS...
ESPECIALLY MONDAY NIGHT WHEN SEAS COME UP SOME.
THE NEXT SURGE COMES WEDNESDAY AND WEDNESDAY NIGHT BEHIND A STRONG
COLD FRONT. MODERATE CHANCES FOR SMALL CRAFT ADVISORIES WITH THE
MID-WEEK SYSTEM.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR AMZ350-
374.
&&
$$
SYNOPSIS...JRL
NEAR TERM...BDC
SHORT TERM...JRL
LONG TERM...JRL
AVIATION...BDC
MARINE...BDC/JRL
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
759 AM EST FRI FEB 21 2014
.UPDATE...
LINE OF CONVECTION/PRECIPITATION PROGRESSING QUICKLY ACROSS THE
FORECAST AREA. HAVE BEEN ABLE TO CLEAR SV.A 21. SV.A 22 REMAINS IN
EFFECT UNTIL 2 PM...HOWEVER THE PORTION IN OUR FORECAST AREA WILL
LIKELY BE CLEAR OF CONVECTION BY LATE MORNING AT THE CURRENT PACE.
POP AND SKY GRIDS LOOK GOOD WITH RESPECT TO CURRENT RADAR/SATELLITE
TRENDS SO NO MAJOR CHANGES PLANNED TO THE CURRENT GRIDS AT THIS TIME.
20
&&
.PREV DISCUSSION... /ISSUED 650 AM EST FRI FEB 21 2014/
PREV DISCUSSION... /ISSUED 504 AM EST FRI FEB 21 2014/
UPDATE...
AFD UPDATE TO REFRESH FFC WATCH/WARNING/ADVISORY SECTION BELOW.
PREV DISCUSSION... /ISSUED 322 AM EST FRI FEB 21 2014/
SHORT TERM /TODAY THROUGH SATURDAY/...
MAIN FORECAST CONCERN THROUGH THE SHORT TERM CONTINUES TO BE THE
COLD FRONT PUSHING INTO NORTHWEST GEORGIA THIS MORNING. OVERALL
MODELS STILL CONSISTENT WITH THE TIMING OF THE SYSTEM THROUGH THE
AREA...AND FORECAST IS SKEWED TOWARDS HRRR AND LOCAL WRF FOR TIMING
OF THE FRONT PUSHING OUT OF THE CWA. ANTICIPATE THE BULK OF THE
ACTIVITY TO BE THROUGH THE ATL AREA 08-11Z...AND THROUGH THE MCN
AREA BY 11-13Z.
SEVERE POTENTIAL ENOUGH TO ISSUE SVR TSTM WATCH THROUGH SUNRISE. NAM
CONTINUES TO ADVERTISE THE HIGHER MUCAPE VALUES...WITH THE GFS STILL
AROUND 300-400J/KG AND MODELED LOW LEVEL SHEAR STILL IN THE 45-50KT
RANGE. OVERALL THE TORNADO THREAT IS MARGINAL AND IS EXPECTED
GRADUALLY LESSON THROUGH THE EARLY MORNING HOURS. THAT BEING
SAID...AN ISOLATED TORNADO CAN NOT BE RULED OUT ENTIRELY. A TORNADO
WATCH CONTINUES THROUGH 10Z FOR NORTHERN PORTIONS OF THE CWA. THE
MAIN CONCERN CONTINUES TO BE THE DAMAGING WINDS ASSOCIATED WITH THE
LINE GIVEN THE SUFFICIENT WIND SHEAR AND INSTABILITY. SOME ROTATION
HAS BEEN NOTED /ALBEIT BROAD/ IN THESE STORMS AS THEY HAVE MOVED
INTO THE STATE.
AS THE STORMS MOVE THROUGH...THE THREAT OF SEVERE ACTIVITY DROPS OFF
QUICKLY. LIGHT RAIN SHOWERS WILL PERSIST BEHIND THE MAIN LINE FOR A FEW
HOURS BEFORE CLEARING BEGINS.
WINDS ASSOCIATED WITH THE LINE WILL ALSO DIMINISH INTO THE DAYLIGHT
HOURS. GUSTY WINDS AHEAD OF THE FRONT AND THE DAMAGING WINDS
EMBEDDED WITHIN THE CONVECTION COULD BRING DOWN ALREADY WEAKENED
TREES ESPECIALLY VULNERABLE FROM THE RECENT ICE STORM.
QPF OF 1-1.25 INCHES WITH LOCALLY HIGHER AMOUNTS ACROSS NORTHWEST
GEORGIA COULD RESULT IN QUICKLY RISING CREEKS AND RIVERS.
BEHIND THE FRONT...HIGH PRESSURE BUILDING INTO THE REGION WILL KEEP
THE REMAINDER OF THE SHORT TERM DRY. LOOKING FOR HIGHS IN THE 60S
FRIDAY AND SATURDAY...WITH LOWS IN THE 30S SATURDAY MORNING.
31
LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
THE OVERALL ACTIVE PATTERN CONTINUES INTO THE EXTENDED PERIOD. MODELS
CONTINUE TO SHOW NEARLY ZONAL FLOW ACROSS THE AREA INTO THE LONG
TERM. A WEAK UPPER LEVEL DISTURBANCE WITHIN THIS ZONAL FLOW
INTERACTS WITH AN OLD FRONTAL BOUNDARY ACROSS THE SOUTHERN PORTION
OF THE STATE. AS A RESULT...HAVE CONTINUED WITH THE SLIGHT CHANCE
TO CHANCE POPS SUNDAY...WITH THE BEST CHANCES FARTHER SOUTH. A
REINFORCING COLD FRONT PUSHES ACROSS THE AREA SUNDAY NIGHT INTO
MONDAY...WITH A DRY AND COOLER AIR MASS RETURNING TO THE STATE
MONDAY. BY MID WEEK...WEAK FRONTAL BOUNDARY MEANDERING ACROSS THE
STATE INTERACTS WITH THE FLOW ALOFT...BUT MODEL UNCERTAINTY STILL
HIGH ENOUGH TO JUST CONTINUE WITH SLIGHT CHANCES OF SHOWERS. WITH
LIMITED INSTABILITY AND WIND SHEAR...HAVE CONTINUED TO LEAVE OUT
MENTION OF THUNDERSTORMS AT THIS TIME.
39
&&
AVIATION...
12Z UPDATE...
AREA OF SHOWERS AND THUNDERSTORMS HAS ALMOST PUSHED EAST OF THE
ATL METRO TAF SITES. EXPECT IT TO CLEAR THE AHN...CSG...AND MCN
AREAS BY 14Z. GUSTY NW WINDS WILL CONTINUE THROUGH MID
MORNING...THEN EXPECT SUSTAINED 8-12KT. WINDS DIMINISH OVERNIGHT.
VFR CONDITIONS BY THE AFTERNOON.
ATL CONFIDENCE...12Z UPDATE... LOW CONFIDENCE ON CIGS THROUGH
14Z...OTHERWISE HIGH CONFIDENCE.
31
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 63 36 68 40 / 100 5 5 10
ATLANTA 61 39 66 43 / 70 5 5 10
BLAIRSVILLE 57 32 63 36 / 60 5 5 10
CARTERSVILLE 61 32 66 38 / 40 5 5 10
COLUMBUS 63 39 67 41 / 80 5 5 20
GAINESVILLE 62 38 65 40 / 70 5 5 10
MACON 64 34 68 40 / 100 5 5 10
ROME 60 31 65 36 / 20 5 5 10
PEACHTREE CITY 61 30 66 36 / 70 5 5 10
VIDALIA 68 45 70 46 / 100 10 5 10
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
SEVERE THUNDERSTORM WATCH UNTIL 2 PM EST THIS AFTERNOON FOR THE
FOLLOWING ZONES: BALDWIN...BLECKLEY...DODGE...EMANUEL...
GLASCOCK...HANCOCK...JEFFERSON...JOHNSON...LAURENS...
MONTGOMERY...PULASKI...TALIAFERRO...TELFAIR...TOOMBS...
TREUTLEN...TWIGGS...WARREN...WASHINGTON...WHEELER...WILCOX...
WILKES...WILKINSON.
&&
$$
SHORT TERM...20
LONG TERM....BDL
AVIATION...20
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
716 AM EST FRI FEB 21 2014
.SYNOPSIS...
HIGH PRESSURE WILL RETREAT EASTWARD TONIGHT IN ADVANCE OF AN APPROACHING
COLD FRONT. THE COLD FRONT WILL SWEEP THROUGH THE AREA ON FRIDAY...STALLING
JUST OFFSHORE UNTIL STRONGER HIGH PRESSURE BUILDS INTO THE AREA ON
MONDAY. A LOW PRESSURE SYSTEM COULD DEVELOP OFF THE SOUTHEAST COAST
LATE TUESDAY INTO WEDNESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
NEAR DAWN...FAIRLY ORGANIZED LINE OF CONVECTION MOVING IN FROM THE
WEST OVER EAST CENTRAL GEORGIA. A SEVERE THUNDERSTORM WATCH HAS BEEN
ISSUED FOR OUR ENTIRE FORECAST AREA AS TSTMS EXPECTED TO MOVE
THROUGH AT A DECENT CLIP. LATEST SPC RUC MESOANALYSIS INDICATES
MODERATE INSTABILITY BETWEEN 500 MB AND 700 MB WITH LAPSE RATES OF
-6.5C. THE LINE WILL BE MOVING INTO A SLIGHTLY LESS FAVORABLE
ENVIRONMENT OVER OUR INLAND GEORGIA ZONES IN THE NEXT COUPLE OF
HOURS...HOWEVER MUCH BETTER INSTABILITY IN PLACE OVER SE SOUTH
CAROLINA WITH SB LIFTED INDICES OF -3. LATEST HRRR FORECAST
CONVECTION PROGS SUGGEST SHOWERS AND STORMS COVERAGE AND INTENSITY
COULD INCREASE AFTER 15Z...THEN NEAR THE COAST AROUND MIDDAY.
A STRONG MID LEVEL SHORT WAVE RIDING BELOW THE LARGE/DEEP CLOSED UPPER
LOW OVER THE GREAT LAKES WAS IMPRESSIVE EARLY THIS MORNING ON WATER
VAPOR SATELLITE IMAGERY. THIS FEATURE WILL DIG THE MEAN UPPER TROUGH
THROUGH THE TENNESSEE/OHIO VALLEYS THIS MORNING THEN LIFT TOWARD NEW
ENGLAND LATE TODAY. SUBTLE NEGATIVE TILTING APPEARS TO BE STRONGER
OFF TO THE NORTH OF OUR FORECAST AREA THROUGH MID AFTERNOON.
ONGOING TRENDS THIS MORNING HAVE INCREASED OUR CONCERNS FOR SEVERE
WEATHER POTENTIAL IN THE PRE-FRONTAL ENVIRONMENT THROUGH MID
AFTERNOON. THE FIRST...OBVIOUSLY THE MUCH WARMER THAN GUIDANCE
READINGS THAT HAVE BECOME ROOTED ACROSS SE GEORGIA AND EASTERN SOUTH
CAROLINA EARLY THIS MORNING BEFORE DAYBREAK. ALTHOUGH TIMING OF
THE CONVECTIVE LINE THROUGH THE FORECAST AREA REMAINS FAIRLY
CONSISTENT FROM PREVIOUS MODEL RUNS TODAY...IT IS NOT GOING TO
TAKE MUCH TO ALLOW TEMPS TO RISE WARMER INTO THE LOWER TO MID 70S
THIS MORNING. UPSTREAM CONVECTION OVERNIGHT HAS BEEN QUITE
ROBUST WITH THE LATEST RAP SHOWING SURFACE BASED INSTABILITY INTO SW
GEORGIA WITH SBCAPES OVER 750 J/KG AT 08Z. SOME OF FORECAST AREAS
COULD SEE SOME THINNER CLOUDS THROUGH MID MORNING AS DENSE CLOUD
COVER WILL BE COMING IN LATER IN THE MORNING.
SPC HAS OUR REGION IN A SLIGHT RISK OF SEVERE CONVECTION AND THERE
APPEARS TO BE NO REASON TO DOUBT IT PER LATEST MESOSCALE TRENDS.
00Z HIGH RESOLUTION GUIDANCE INDICATING POTENTIAL FOR HIGHER DBZ CORES
AND LINEAR ORGANIZATION. GIVEN THE STRONG WIND FIELDS...SMALL BOWS
WOULD BE A CONCERN ALONG WITH POSSIBLE FORMATION OF A DECENT REAR
INFLOW JET. CONCERN FALLS OVER OUR NW TIER OF ZONES THAT SUFFERED
GREAT TIMBER DAMAGE FROM THE RECENT ICE STORM. TSTM GUST IMPACTS
COULD CERTAINLY BE MUCH GREATER IN THOSE ZONES WHERE WEAK AND
BROKEN LIMBS ALREADY LACE THAT REGION. EVEN A MARGINALLY GUSTY
SQUALL LINE COULD MAKE FOR SOME BAD TIMES IN SOME AREAS AND WE
WILL REMAIN COGNIZANT OF THIS SITUATION. WE WILL RAMP UP SEVERE
WORDING A BIT IN OUR HAZARDOUS WEATHER OUTLOOK THIS MORNING
ALTHOUGH IT IS STILL MORE LIKELY THAT WE ONLY SEE ONLY SEE
ISOLATED OCCURRENCES OF 50 KT CONVECTIVE WIND GUSTS IN THE
CONVECTIVE SEGMENTS/LINES AS TIMING AND STRENGTH OF DYNAMICS DO
NOT APPEAR TO COMPLETELY COME IN SYNC FOR A MORE WIDESPREAD
EVENT.
THE COLD FRONT WILL RACE THROUGH THE FORECAST AREA THIS AFTERNOON AND
OFFSHORE BY EARLY EVENING. MUCH COOLER TEMPS EXPECTED TONIGHT WITH
LOWS IN THE 40S AND GRADUALLY CLEARING SKIES.
&&
.SHORT TERM /SATURDAY THROUGH MONDAY/...
DRY HIGH PRESSURE WILL SETTLE OVER THE REGION ON SATURDAY. AMPLE
MOISTURE WITHIN A 105 KT JET OVER THE DEEP SOUTH WILL PRODUCE
EXTENSIVE CIRRUS WHICH WILL SLIGHTLY LIMIT INSOLATION. HOWEVER HIGH
TEMPS WILL STILL REACH 70F IN MANY SPOTS.
ON SUNDAY WE START TO SEE SOME CHANNELED VORTICITY ENERGY MOVE INTO
THE EASTERN UNITED STATES. MEANWHILE THE LOW-LEVEL RIDGE OVER THE
WESTERN ATLANTIC STARTS TO SHIFT EAST AS THE FLOW BACKS TO
SOUTHWESTERLY. AS LOW-LEVEL MOISTURE INCREASES...WEAK ISENTROPIC
ASCENT WILL DEVELOP ACROSS SOUTHEAST GA WITH SOME RAIN SHOWERS
POSSIBLE BY SUNDAY AFTERNOON. WE ADDED A SLIGHT CHANCE OF TSTMS
ACROSS FAR SOUTHERN AREAS BECAUSE A POCKET OF ELEVATED INSTABILITY
SHIFTS THROUGH DURING THIS TIME. LOW-LEVEL WARM ADVECTION WILL PUSH
HIGH TEMPS INTO THE LOWER TO MIDDLE 70S.
A BACKDOOR COLD FRONT WILL DROP INTO THE AREA SUNDAY NIGHT AND PUSH
OFFSHORE ON MONDAY. UPPER DYNAMICS ARE NOT VERY IMPRESSIVE
ACCOMPANYING THE FROPA SO WE ONLY HAVE 20-40 POPS SUNDAY NIGHT.
ON MONDAY...SLIGHTLY COOLER HIGH PRESSURE WILL BUILD IN FROM THE
NORTH WHILE THE BACKDOOR FRONT SITS JUST SOUTH OF THE AREA.
EXTENSIVE CLOUD COVER WILL ALSO PERSIST THOUGH THE BEST RAIN CHANCES
WILL BE FAR SOUTH CLOSER TO THE FRONT. WE SHOW HIGH TEMPS IN THE
MID/UPPER 60S.
&&
.LONG TERM /MONDAY NIGHT THROUGH THURSDAY/...
THE LONG TERM PATTERN WILL MAINLY BE DOMINATED BY A LOBE OF THE
POLAR VORTEX MOVING INTO THE GREAT LAKES REGION LATE WEEK. MONDAY
NIGHT THROUGH WEDNESDAY THE UPPER PATTERN WILL BE TRENDING TOWARD A
BROAD TROUGH REGIME WITH A SERIES OF WEAK FRONTS AND LOW PRESSURE
WAVES AFFECTING THE FORECAST AREA. DUE TO LARGE UNCERTAINTIES IN
TIMING INDIVIDUAL FEATURES WE MAINTAINED A CONSERVATIVE FORECAST
WITH MAINLY SLIGHT CHANCES FOR SHOWERS AND HIGH TEMPS IN THE 60S.
A STRONG COLD FRONT WILL SWEEP THROUGH WEDNESDAY NIGHT... FOLLOWED
BY COOL CANADIAN HIGH PRESSURE THURSDAY AND FRIDAY. THIS WILL BRING
DRY CONDITIONS AND BELOW-NORMAL TEMPERATURES.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
EARLIER CONCERNS WITH FOG HAS TURNED TO CONCERN FOR STRONG CONVECTION
MOVING INTO THE COASTAL CORRIDOR AFTER MID MORNING AND THEN
EXITING PRIOR TO MID AFTERNOON. PRIOR TO THE RAINS TODAY...GUSTY SW
SURFACE WINDS WERE DEVELOPING AHEAD OF THE SQUALL LINE ALONG WITH
FAIRLY WIDESPREAD MVFR CIGS. THERE COULD BE A BRIEF BOUT OF IFR CIGS
BUT THE WINDOW LOOKS FAIRLY BRIEF. STILL A BIT EARLY TO COMMIT TSRA
AS THE LINE COULD BE PREDOMINATELY MORE SHALLOW...HOWEVER WE BELIEVE
THUNDER WILL HAVE TO BE ADDED AT SOME POINT BY MID MORNING GIVEN
RADAR TRENDS. SKIES WILL BEGIN TO CLEAR OUT THIS EVENING WITH VFR
CONDITIONS EXPECTED TONIGHT IN THE WAKE OF A COLD FRONT.
EXTENDED AVIATION OUTLOOK...MVFR CEILINGS POSSIBLE AT KSAV SATURDAY
NIGHT AND AT BOTH TERMINALS SUNDAY NIGHT INTO MONDAY MORNING.
OTHERWISE VFR.
&&
.MARINE...
LITTLE TO NO REPORTS OF DENSE SEA FOG OVERNIGHT ALONG THE COAST WITH
SATELLITE IMAGERY ALSO NOT SUPPORTING OF FOG BASED LOW STRATUS OFF
THE COAST. THERE STILL IS A CHANCE FOR SEA FOG BUT GIVEN LATEST TRENDS
WE OPTED TO CANCEL MARINE FOG ADVISORIES AND JUST FORECAST PATCHY DENSE
FOG OVER THE WATERS THROUGH EARLY AFTERNOON WHEN RAIN CHANCES INCREASE
AND THE COLD FRONT NEARS. A SEVERE TSTM WATCH IS IN EFFECT FOR
NEAR SHORE WATERS AND THE CHARLESTON HARBOR.
OTHERWISE...NOT MUCH MIXING GOING ON OVER CHILLY SHELF WATERS AND IT
IS INTERESTING TO SEE WINDS GUSTS TO 20 KT AT TIMES AT CHARLESTON
AND SAVANNAH WHERE TEMPS HAVE WARMED TO THE UPPER 60S. TEMPS AT
GRAYS REEF NEAR 60 AND WINDS BELOW 10 KT ALL NIGHT WITH 2-3 FT
SEAS...QUITE THE STRONG MARINE INVERSION. SEAS WILL CONTINUE TO BUILD
OFFSHORE AND MAINTAINED A MARGINAL SCA FOR CHARLESTON COUNTY
WATERS MAINLY WELL EAST OF BULLS BAY. MOST NEAR SHORE WATERS TODAY
WILL SEE SW WINDS 15 KT OR SO AND SEAS 3-4 FT TOPS. THERE IS ALSO
A SCA FOR OUR OUTER GEORGIA WATERS WITH OCCASIONALLY GUSTY SW FLOW
AND SEAS 4-7 FT...HIGHEST NEAR THE WEST WALL OF THE GULF STREAM.
THE FRONT MOVES THROUGH THIS EVENING WITH WINDS SHIFTING W OR WNW
TONIGHT WITH COLD AIR ADVECTION MORE GRADUAL THAN SHARP...CONDITIONS
BELOW SCA CRITERIA.
MARINE WINDS/SEAS WILL BE RATHER LIGHT SATURDAY THROUGH SUNDAY
BEFORE A COLD FRONT DROPS INTO THE WATER SUNDAY NIGHT. WINDS WILL
INCREASE ALONG THE FRONT BUT THE STRONGER SURGE COMES MONDAY AS THE
FLOW BECOMES NE. CONDITIONS COULD FLIRT WITH ADVISORY LEVELS...
ESPECIALLY MONDAY NIGHT WHEN SEAS COME UP SOME.
THE NEXT SURGE COMES WEDNESDAY AND WEDNESDAY NIGHT BEHIND A STRONG
COLD FRONT. MODERATE CHANCES FOR SMALL CRAFT ADVISORIES WITH THE
MID-WEEK SYSTEM.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR AMZ350-
374.
&&
$$
SYNOPSIS...
NEAR TERM...
SHORT TERM...JRL
LONG TERM...JRL
AVIATION...
MARINE...JRL
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
650 AM EST FRI FEB 21 2014
.PREV DISCUSSION... /ISSUED 504 AM EST FRI FEB 21 2014/
UPDATE...
AFD UPDATE TO REFRESH FFC WATCH/WARNING/ADVISORY SECTION BELOW.
PREV DISCUSSION... /ISSUED 322 AM EST FRI FEB 21 2014/
SHORT TERM /TODAY THROUGH SATURDAY/...
MAIN FORECAST CONCERN THROUGH THE SHORT TERM CONTINUES TO BE THE
COLD FRONT PUSHING INTO NORTHWEST GEORGIA THIS MORNING. OVERALL
MODELS STILL CONSISTENT WITH THE TIMING OF THE SYSTEM THROUGH THE
AREA...AND FORECAST IS SKEWED TOWARDS HRRR AND LOCAL WRF FOR TIMING
OF THE FRONT PUSHING OUT OF THE CWA. ANTICIPATE THE BULK OF THE
ACTIVITY TO BE THROUGH THE ATL AREA 08-11Z...AND THROUGH THE MCN
AREA BY 11-13Z.
SEVERE POTENTIAL ENOUGH TO ISSUE SVR TSTM WATCH THROUGH SUNRISE. NAM
CONTINUES TO ADVERTISE THE HIGHER MUCAPE VALUES...WITH THE GFS STILL
AROUND 300-400J/KG AND MODELED LOW LEVEL SHEAR STILL IN THE 45-50KT
RANGE. OVERALL THE TORNADO THREAT IS MARGINAL AND IS EXPECTED
GRADUALLY LESSON THROUGH THE EARLY MORNING HOURS. THAT BEING
SAID...AN ISOLATED TORNADO CAN NOT BE RULED OUT ENTIRELY. A TORNADO
WATCH CONTINUES THROUGH 10Z FOR NORTHERN PORTIONS OF THE CWA. THE
MAIN CONCERN CONTINUES TO BE THE DAMAGING WINDS ASSOCIATED WITH THE
LINE GIVEN THE SUFFICIENT WIND SHEAR AND INSTABILITY. SOME ROTATION
HAS BEEN NOTED /ALBEIT BROAD/ IN THESE STORMS AS THEY HAVE MOVED
INTO THE STATE.
AS THE STORMS MOVE THROUGH...THE THREAT OF SEVERE ACTIVITY DROPS OFF
QUICKLY. LIGHT RAIN SHOWERS WILL PERSIST BEHIND THE MAIN LINE FOR A FEW
HOURS BEFORE CLEARING BEGINS.
WINDS ASSOCIATED WITH THE LINE WILL ALSO DIMINISH INTO THE DAYLIGHT
HOURS. GUSTY WINDS AHEAD OF THE FRONT AND THE DAMAGING WINDS
EMBEDDED WITHIN THE CONVECTION COULD BRING DOWN ALREADY WEAKENED
TREES ESPECIALLY VULNERABLE FROM THE RECENT ICE STORM.
QPF OF 1-1.25 INCHES WITH LOCALLY HIGHER AMOUNTS ACROSS NORTHWEST
GEORGIA COULD RESULT IN QUICKLY RISING CREEKS AND RIVERS.
BEHIND THE FRONT...HIGH PRESSURE BUILDING INTO THE REGION WILL KEEP
THE REMAINDER OF THE SHORT TERM DRY. LOOKING FOR HIGHS IN THE 60S
FRIDAY AND SATURDAY...WITH LOWS IN THE 30S SATURDAY MORNING.
31
LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
THE OVERALL ACTIVE PATTERN CONTINUES INTO THE EXTENDED PERIOD. MODELS
CONTINUE TO SHOW NEARLY ZONAL FLOW ACROSS THE AREA INTO THE LONG
TERM. A WEAK UPPER LEVEL DISTURBANCE WITHIN THIS ZONAL FLOW
INTERACTS WITH AN OLD FRONTAL BOUNDARY ACROSS THE SOUTHERN PORTION
OF THE STATE. AS A RESULT...HAVE CONTINUED WITH THE SLIGHT CHANCE
TO CHANCE POPS SUNDAY...WITH THE BEST CHANCES FARTHER SOUTH. A
REINFORCING COLD FRONT PUSHES ACROSS THE AREA SUNDAY NIGHT INTO
MONDAY...WITH A DRY AND COOLER AIR MASS RETURNING TO THE STATE
MONDAY. BY MID WEEK...WEAK FRONTAL BOUNDARY MEANDERING ACROSS THE
STATE INTERACTS WITH THE FLOW ALOFT...BUT MODEL UNCERTAINTY STILL
HIGH ENOUGH TO JUST CONTINUE WITH SLIGHT CHANCES OF SHOWERS. WITH
LIMITED INSTABILITY AND WIND SHEAR...HAVE CONTINUED TO LEAVE OUT
MENTION OF THUNDERSTORMS AT THIS TIME.
39
&&
.AVIATION...
12Z UPDATE...
AREA OF SHOWERS AND THUNDERSTORMS HAS ALMOST PUSHED EAST OF THE
ATL METRO TAF SITES. EXPECT IT TO CLEAR THE AHN...CSG...AND MCN
AREAS BY 14Z. GUSTY NW WINDS WILL CONTINUE THROUGH MID
MORNING...THEN EXPECT SUSTAINED 8-12KT. WINDS DIMINISH OVERNIGHT.
VFR CONDITIONS BY THE AFTERNOON.
//ATL CONFIDENCE...12Z UPDATE...
LOW CONFIDENCE ON CIGS THROUGH 14Z...OTHERWISE HIGH CONFIDENCE.
31
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 63 36 68 40 / 90 5 5 10
ATLANTA 61 39 66 43 / 70 5 5 10
BLAIRSVILLE 57 32 63 36 / 60 5 5 10
CARTERSVILLE 61 32 66 38 / 40 5 5 10
COLUMBUS 63 39 67 41 / 80 5 5 20
GAINESVILLE 62 38 65 40 / 70 5 5 10
MACON 64 34 68 40 / 100 5 5 10
ROME 60 31 65 36 / 20 5 5 10
PEACHTREE CITY 61 30 66 36 / 70 5 5 10
VIDALIA 68 45 70 46 / 90 10 5 10
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
SEVERE THUNDERSTORM WATCH UNTIL 2 PM EST THIS AFTERNOON FOR THE
FOLLOWING ZONES: BALDWIN...BLECKLEY...DODGE...EMANUEL...
GLASCOCK...HANCOCK...JEFFERSON...JOHNSON...LAURENS...
MONTGOMERY...PULASKI...TALIAFERRO...TELFAIR...TOOMBS...
TREUTLEN...TWIGGS...WARREN...WASHINGTON...WHEELER...WILCOX...
WILKES...WILKINSON.
SEVERE THUNDERSTORM WATCH UNTIL 9 AM EST THIS MORNING FOR THE
FOLLOWING ZONES: BIBB...CRAWFORD...CRISP...DOOLY...GREENE...
HOUSTON...JASPER...JONES...MACON...MARION...MONROE...MORGAN...
OGLETHORPE...PEACH...PUTNAM...SCHLEY...STEWART...SUMTER...
TAYLOR...WEBSTER.
&&
$$
SHORT TERM...31
LONG TERM....39
AVIATION...31
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
504 AM EST FRI FEB 21 2014
.UPDATE...
AFD UPDATE TO REFRESH FFC WATCH/WARNING/ADVISORY SECTION BELOW.
&&
.PREV DISCUSSION... /ISSUED 322 AM EST FRI FEB 21 2014/
SHORT TERM /TODAY THROUGH SATURDAY/...
MAIN FORECAST CONCERN THROUGH THE SHORT TERM CONTINUES TO BE THE
COLD FRONT PUSHING INTO NORTHWEST GEORGIA THIS MORNING. OVERALL
MODELS STILL CONSISTENT WITH THE TIMING OF THE SYSTEM THROUGH THE
AREA...AND FORECAST IS SKEWED TOWARDS HRRR AND LOCAL WRF FOR TIMING
OF THE FRONT PUSHING OUT OF THE CWA. ANTICIPATE THE BULK OF THE
ACTIVITY TO BE THROUGH THE ATL AREA 08-11Z...AND THROUGH THE MCN
AREA BY 11-13Z.
SEVERE POTENTIAL ENOUGH TO ISSUE SVR TSTM WATCH THROUGH SUNRISE. NAM
CONTINUES TO ADVERTISE THE HIGHER MUCAPE VALUES...WITH THE GFS STILL
AROUND 300-400J/KG AND MODELED LOW LEVEL SHEAR STILL IN THE 45-50KT
RANGE. OVERALL THE TORNADO THREAT IS MARGINAL AND IS EXPECTED
GRADUALLY LESSON THROUGH THE EARLY MORNING HOURS. THAT BEING
SAID...AN ISOLATED TORNADO CAN NOT BE RULED OUT ENTIRELY. A TORNADO
WATCH CONTINUES THROUGH 10Z FOR NORTHERN PORTIONS OF THE CWA. THE
MAIN CONCERN CONTINUES TO BE THE DAMAGING WINDS ASSOCIATED WITH THE
LINE GIVEN THE SUFFICIENT WIND SHEAR AND INSTABILITY. SOME ROTATION
HAS BEEN NOTED /ALBEIT BROAD/ IN THESE STORMS AS THEY HAVE MOVED
INTO THE STATE.
AS THE STORMS MOVE THROUGH...THE THREAT OF SEVERE ACTIVITY DROPS OFF
QUICKLY. LIGHT RAIN SHOWERS WILL PERSIST BEHIND THE MAIN LINE FOR A FEW
HOURS BEFORE CLEARING BEGINS.
WINDS ASSOCIATED WITH THE LINE WILL ALSO DIMINISH INTO THE DAYLIGHT
HOURS. GUSTY WINDS AHEAD OF THE FRONT AND THE DAMAGING WINDS
EMBEDDED WITHIN THE CONVECTION COULD BRING DOWN ALREADY WEAKENED
TREES ESPECIALLY VULNERABLE FROM THE RECENT ICE STORM.
QPF OF 1-1.25 INCHES WITH LOCALLY HIGHER AMOUNTS ACROSS NORTHWEST
GEORGIA COULD RESULT IN QUICKLY RISING CREEKS AND RIVERS.
BEHIND THE FRONT...HIGH PRESSURE BUILDING INTO THE REGION WILL KEEP
THE REMAINDER OF THE SHORT TERM DRY. LOOKING FOR HIGHS IN THE 60S
FRIDAY AND SATURDAY...WITH LOWS IN THE 30S SATURDAY MORNING.
31
LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
THE OVERALL ACTIVE PATTERN CONTINUES INTO THE EXTENDED PERIOD. MODELS
CONTINUE TO SHOW NEARLY ZONAL FLOW ACROSS THE AREA INTO THE LONG
TERM. A WEAK UPPER LEVEL DISTURBANCE WITHIN THIS ZONAL FLOW
INTERACTS WITH AN OLD FRONTAL BOUNDARY ACROSS THE SOUTHERN PORTION
OF THE STATE. AS A RESULT...HAVE CONTINUED WITH THE SLIGHT CHANCE
TO CHANCE POPS SUNDAY...WITH THE BEST CHANCES FARTHER SOUTH. A
REINFORCING COLD FRONT PUSHES ACROSS THE AREA SUNDAY NIGHT INTO
MONDAY...WITH A DRY AND COOLER AIR MASS RETURNING TO THE STATE
MONDAY. BY MID WEEK...WEAK FRONTAL BOUNDARY MEANDERING ACROSS THE
STATE INTERACTS WITH THE FLOW ALOFT...BUT MODEL UNCERTAINTY STILL
HIGH ENOUGH TO JUST CONTINUE WITH SLIGHT CHANCES OF SHOWERS. WITH
LIMITED INSTABILITY AND WIND SHEAR...HAVE CONTINUED TO LEAVE OUT
MENTION OF THUNDERSTORMS AT THIS TIME.
39
AVIATION...
06Z UPDATE...
LINE OF SHOWERS AND THUNDERSTORMS EXPECTED TO MOVE THROUGH THE
AREA OVERNIGHT...WITH DEGRADING CIGS AND VSBYS ACCOMPANYING THE
TSRA. HAVE TIMED THE SQUALL LINE THROUGH THE ATL AREA BY 10Z...AND
THE MCN AND AHN AREAS BY AROUND 12Z. S-SW GUSTY WINDS /15G25KT OR
SO/ WILL BECOME NW AT 13-15KT GUSTS TO 22-25KT BEHIND THE LINE.
EXPECT HIGH IFR OR LOW MVFR CIGS WITH THE POST-TSRA LIGHT
RAIN...WITH SLOW IMPROVEMENT THROUGH FRIDAY MORNING...AND VFR BY AFTERNOON.
//ATL CONFIDENCE...06Z UPDATE...
MEDIUM CONFIDENCE ON ALL ELEMENTS.
31
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 63 36 68 40 / 90 5 5 10
ATLANTA 61 39 66 43 / 70 5 5 10
BLAIRSVILLE 57 32 63 36 / 60 5 5 10
CARTERSVILLE 61 32 66 38 / 40 5 5 10
COLUMBUS 63 39 67 41 / 80 5 5 20
GAINESVILLE 62 38 65 40 / 70 5 5 10
MACON 64 34 68 40 / 100 5 5 10
ROME 60 31 65 36 / 20 5 5 10
PEACHTREE CITY 61 30 66 36 / 70 5 5 10
VIDALIA 68 45 70 46 / 90 10 5 10
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
SEVERE THUNDERSTORM WATCH UNTIL 9 AM EST THIS MORNING FOR THE
FOLLOWING ZONES: BARROW...BIBB...BUTTS...CARROLL...
CHATTAHOOCHEE...CLARKE...CLAYTON...COBB...COWETA...CRAWFORD...
CRISP...DEKALB...DOOLY...DOUGLAS...FAYETTE...GREENE...GWINNETT...
HARALSON...HARRIS...HEARD...HENRY...HOUSTON...JASPER...JONES...
LAMAR...MACON...MARION...MERIWETHER...MONROE...MORGAN...
MUSCOGEE...NEWTON...NORTH FULTON...OCONEE...OGLETHORPE...
PAULDING...PEACH...PIKE...POLK...PUTNAM...ROCKDALE...SCHLEY...
SOUTH FULTON...SPALDING...STEWART...SUMTER...TALBOT...TAYLOR...
TROUP...UPSON...WALTON...WEBSTER.
&&
$$
SHORT TERM...31
LONG TERM....39
AVIATION...31
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
421 AM EST FRI FEB 21 2014
.SYNOPSIS...
HIGH PRESSURE WILL RETREAT EASTWARD TONIGHT IN ADVANCE OF AN APPROACHING
COLD FRONT. THE COLD FRONT WILL SWEEP THROUGH THE AREA ON FRIDAY...STALLING
JUST OFFSHORE UNTIL STRONGER HIGH PRESSURE BUILDS INTO THE AREA ON
MONDAY. A LOW PRESSURE SYSTEM COULD DEVELOP OFF THE SOUTHEAST COAST
LATE TUESDAY INTO WEDNESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
PRE-DAWN...IMPRESSIVE COOL SEASON NOCTURNAL WARM AIR ADVECTION PATTERN
IN FULL TILT WITH TEMPS WARMING INTO THE MID TO UPPER 60S OVERNIGHT
AS MIXING FROM THE LOW LEVEL JET RESULTING IN AN INCREASING SSW
BREEZE MANY LOCATIONS...ESPECIALLY ALONG AND E OF I-95. THIS HAS
REDUCED POTENTIAL FOR FOG AND MOST RECENT WEB CAMS ALONG THE
BEACHES HAVE BEEN FOG FREE FOR MUCH OF THE OVERNIGHT. THERE STILL
IS POTENTIAL FOR SOME DENSE SEA FOG TO BRUSH THE COAST BUT LATEST
THINKING IS FOR MORE OF A TRANSIENT/PATCHY SCENARIO AND HAVE
ALLOWED LAND-BASED FOG ADVISORIES TO COME DOWN. MOST AREAS WILL
REMAIN DRY AT DAWN BUT CONVECTIVE RAINS WILL BE NEARING OUR FAR
INLAND ZONES AT THAT TIME. WE CANCELLED A DENSE FOG ADVISORY FOR
COASTAL ZONES THIS MORNING GIVEN ONGOING OBSERVATION/SATELLITE
TRENDS.
A STRONG MID LEVEL SHORT WAVE RIDING BELOW THE LARGE/DEEP CLOSED UPPER
LOW OVER THE GREAT LAKES WAS IMPRESSIVE EARLY THIS MORNING ON WATER
VAPOR SATELLITE IMAGERY. THIS FEATURE WILL DIG THE MEAN UPPER TROUGH
THROUGH THE TENNESSEE/OHIO VALLEYS THIS MORNING THEN LIFT TOWARD NEW
ENGLAND LATE TODAY. SUBTLE NEGATIVE TILTING APPEARS TO BE STRONGER
OFF TO THE NORTH OF OUR FORECAST AREA THROUGH MID AFTERNOON.
ONGOING TRENDS THIS MORNING HAVE INCREASED OUR CONCERNS FOR SEVERE
WEATHER POTENTIAL IN THE PRE-FRONTAL ENVIRONMENT THROUGH MID
AFTERNOON. THE FIRST...OBVIOUSLY THE MUCH WARMER THAN GUIDANCE
READINGS THAT HAVE BECOME ROOTED ACROSS SE GEORGIA AND EASTERN SOUTH
CAROLINA EARLY THIS MORNING BEFORE DAYBREAK. ALTHOUGH TIMING OF
THE CONVECTIVE LINE THROUGH THE FORECAST AREA REMAINS FAIRLY
CONSISTENT FROM PREVIOUS MODEL RUNS TODAY...IT IS NOT GOING TO
TAKE MUCH TO ALLOW TEMPS TO RISE WARMER INTO THE LOWER TO MID 70S
THIS MORNING. UPSTREAM CONVECTION OVERNIGHT HAS BEEN QUITE
ROBUST WITH THE LATEST RAP SHOWING SURFACE BASED INSTABILITY INTO SW
GEORGIA WITH SBCAPES OVER 750 J/KG AT 08Z. SOME OF FORECAST AREAS
COULD SEE SOME THINNER CLOUDS THROUGH MID MORNING AS DENSE CLOUD
COVER WILL BE COMING IN LATER IN THE MORNING.
SPC HAS OUR REGION IN A SLIGHT RISK OF SEVERE CONVECTION AND THERE
APPEARS TO BE NO REASON TO DOUBT IT PER LATEST MESOSCALE TRENDS.
00Z HIGH RESOLUTION GUIDANCE INDICATING POTENTIAL FOR HIGHER DBZ CORES
AND LINEAR ORGANIZATION. GIVEN THE STRONG WIND FIELDS...SMALL BOWS
WOULD BE A CONCERN ALONG WITH POSSIBLE FORMATION OF A DECENT REAR
INFLOW JET. CONCERN FALLS OVER OUR NW TIER OF ZONES THAT SUFFERED
GREAT TIMBER DAMAGE FROM THE RECENT ICE STORM. TSTM GUST IMPACTS
COULD CERTAINLY BE MUCH GREATER IN THOSE ZONES WHERE WEAK AND
BROKEN LIMBS ALREADY LACE THAT REGION. EVEN A MARGINALLY GUSTY
SQUALL LINE COULD MAKE FOR SOME BAD TIMES IN SOME AREAS AND WE
WILL REMAIN COGNIZANT OF THIS SITUATION. WE WILL RAMP UP SEVERE
WORDING A BIT IN OUR HAZARDOUS WEATHER OUTLOOK THIS MORNING
ALTHOUGH IT IS STILL MORE LIKELY THAT WE ONLY SEE ONLY SEE
ISOLATED OCCURRENCES OF 50 KT CONVECTIVE WIND GUSTS IN THE
CONVECTIVE SEGMENTS/LINES AS TIMING AND STRENGTH OF DYNAMICS DO
NOT APPEAR TO COMPLETELY COME IN SYNC FOR A MORE WIDESPREAD
EVENT.
THE COLD FRONT WILL RACE THROUGH THE FORECAST AREA THIS AFTERNOON AND
OFFSHORE BY EARLY EVENING. MUCH COOLER TEMPS EXPECTED TONIGHT WITH
LOWS IN THE 40S AND GRADUALLY CLEARING SKIES.
&&
.SHORT TERM /SATURDAY THROUGH MONDAY/...
DRY HIGH PRESSURE WILL SETTLE OVER THE REGION ON SATURDAY. AMPLE
MOISTURE WITHIN A 105 KT JET OVER THE DEEP SOUTH WILL PRODUCE
EXTENSIVE CIRRUS WHICH WILL SLIGHTLY LIMIT INSOLATION. HOWEVER HIGH
TEMPS WILL STILL REACH 70F IN MANY SPOTS.
ON SUNDAY WE START TO SEE SOME CHANNELED VORTICITY ENERGY MOVE INTO
THE EASTERN UNITED STATES. MEANWHILE THE LOW-LEVEL RIDGE OVER THE
WESTERN ATLANTIC STARTS TO SHIFT EAST AS THE FLOW BACKS TO
SOUTHWESTERLY. AS LOW-LEVEL MOISTURE INCREASES...WEAK ISENTROPIC
ASCENT WILL DEVELOP ACROSS SOUTHEAST GA WITH SOME RAIN SHOWERS
POSSIBLE BY SUNDAY AFTERNOON. WE ADDED A SLIGHT CHANCE OF TSTMS
ACROSS FAR SOUTHERN AREAS BECAUSE A POCKET OF ELEVATED INSTABILITY
SHIFTS THROUGH DURING THIS TIME. LOW-LEVEL WARM ADVECTION WILL PUSH
HIGH TEMPS INTO THE LOWER TO MIDDLE 70S.
A BACKDOOR COLD FRONT WILL DROP INTO THE AREA SUNDAY NIGHT AND PUSH
OFFSHORE ON MONDAY. UPPER DYNAMICS ARE NOT VERY IMPRESSIVE
ACCOMPANYING THE FROPA SO WE ONLY HAVE 20-40 POPS SUNDAY NIGHT.
ON MONDAY...SLIGHTLY COOLER HIGH PRESSURE WILL BUILD IN FROM THE
NORTH WHILE THE BACKDOOR FRONT SITS JUST SOUTH OF THE AREA.
EXTENSIVE CLOUD COVER WILL ALSO PERSIST THOUGH THE BEST RAIN CHANCES
WILL BE FAR SOUTH CLOSER TO THE FRONT. WE SHOW HIGH TEMPS IN THE
MID/UPPER 60S.
&&
.LONG TERM /MONDAY NIGHT THROUGH THURSDAY/...
THE LONG TERM PATTERN WILL MAINLY BE DOMINATED BY A LOBE OF THE
POLAR VORTEX MOVING INTO THE GREAT LAKES REGION LATE WEEK. MONDAY
NIGHT THROUGH WEDNESDAY THE UPPER PATTERN WILL BE TRENDING TOWARD A
BROAD TROUGH REGIME WITH A SERIES OF WEAK FRONTS AND LOW PRESSURE
WAVES AFFECTING THE FORECAST AREA. DUE TO LARGE UNCERTAINTIES IN
TIMING INDIVIDUAL FEATURES WE MAINTAINED A CONSERVATIVE FORECAST
WITH MAINLY SLIGHT CHANCES FOR SHOWERS AND HIGH TEMPS IN THE 60S.
A STRONG COLD FRONT WILL SWEEP THROUGH WEDNESDAY NIGHT... FOLLOWED
BY COOL CANADIAN HIGH PRESSURE THURSDAY AND FRIDAY. THIS WILL BRING
DRY CONDITIONS AND BELOW-NORMAL TEMPERATURES.
&&
.AVIATION /09Z FRIDAY THROUGH TUESDAY/...
AT KCHS...LOW CONFIDENCE FORECAST OVERNIGHT AS POTENTIAL FOR LOW CLOUDS
IS HIGH BUT TIMING AND AREAL EXTENT/TRANSLATION NEARLY IMPOSSIBLE
TO PIN DOWN THANKS TO AN INCREASING LOW LEVEL JET SCENARIO. WE CARRIED
ON SIMILAR TRENDS FROM THE 00Z TAF CYCLE WITH MVFR CONDITIONS BECOMING
LIKELY CLOSER TO DAYBREAK WITH LESSER CHANCES THE NEXT COUPLE OF HOURS.
CONVECTIVE RAINS INCLUDING CHANCES FOR TSTMS EXPECTED TO SWEEP THROUGH
THE COASTAL CORRIDOR BETWEEN LATE MORNING AND EARLY AFTERNOON WITH
CHANCES FOR A FEW TSTMS WITH GUSTY WINDS. CONDITIONS IMPROVING LATE
AFTERNOON WITH VFR CONDITIONS RETURNING.
AT KSAV...THE LAST TAF AMENDMENT INDICATES POSSIBLE MVFR
CONDITIONS DEVELOPING DUE TO REDUCED CEILINGS FROM SUNRISE TO MID
MORNING. MVFR CONDITIONS ARE THEN MAINTAINED IN SHOWERS THROUGH
ABOUT 19Z. GUSTY SW SURFACE WINDS ARE EXPECTED TO DEVELOP AFTER
MID MORNING AS BETTER MIXING COMMENCES AHEAD OF THE APPROACHING
COLD FRONT. SHOWERS AND A FEW TSTMS WILL PASS THROUGH THE MID TO
LATE MORNING THROUGH EARLY AFTERNOON IMPROVING CONDITIONS TO VFR
LATE AFTERNOON ONWARD.
EXTENDED AVIATION OUTLOOK...MVFR CEILINGS POSSIBLE AT KSAV SATURDAY
NIGHT AND AT BOTH TERMINALS SUNDAY NIGHT INTO MONDAY MORNING.
OTHERWISE VFR.
&&
.MARINE...
LITTLE TO NO REPORTS OF DENSE SEA FOG OVERNIGHT ALONG THE COAST WITH
SATELLITE IMAGERY ALSO NOT SUPPORTING OF FOG BASED LOW STRATUS OFF
THE COAST. THERE STILL IS A CHANCE FOR SEA FOG BUT GIVEN LATEST TRENDS
WE OPTED TO CANCEL MARINE FOG ADVISORIES AND JUST FORECAST PATCHY DENSE
FOG OVER THE WATERS THROUGH EARLY AFTERNOON WHEN RAIN CHANCES INCREASE
AND THE COLD FRONT NEARS.
OTHERWISE...NOT MUCH MIXING GOING ON OVER CHILLY SHELF WATERS AND IT
IS INTERESTING TO SEE WINDS GUSTS TO 20 KT AT TIMES AT CHARLESTON
AND SAVANNAH WHERE TEMPS HAVE WARMED TO THE UPPER 60S. TEMPS AT
GRAYS REEF NEAR 60 AND WINDS BELOW 10 KT ALL NIGHT WITH 2-3 FT
SEAS...QUITE THE STRONG MARINE INVERSION. SEAS WILL CONTINUE TO BUILD
OFFSHORE AND MAINTAINED A MARGINAL SCA FOR CHARLESTON COUNTY
WATERS MAINLY WELL EAST OF BULLS BAY. MOST NEAR SHORE WATERS TODAY
WILL SEE SW WINDS 15 KT OR SO AND SEAS 3-4 FT TOPS. THERE IS ALSO
A SCA FOR OUR OUTER GEORGIA WATERS WITH OCCASIONALLY GUSTY SW FLOW
AND SEAS 4-7 FT...HIGHEST NEAR THE WEST WALL OF THE GULF STREAM.
THE FRONT MOVES THROUGH THIS EVENING WITH WINDS SHIFTING W OR WNW
TONIGHT WITH COLD AIR ADVECTION MORE GRADUAL THAN SHARP...CONDITIONS
BELOW SCA CRITERIA.
MARINE WINDS/SEAS WILL BE RATHER LIGHT SATURDAY THROUGH SUNDAY
BEFORE A COLD FRONT DROPS INTO THE WATER SUNDAY NIGHT. WINDS WILL
INCREASE ALONG THE FRONT BUT THE STRONGER SURGE COMES MONDAY AS THE
FLOW BECOMES NE. CONDITIONS COULD FLIRT WITH ADVISORY LEVELS...
ESPECIALLY MONDAY NIGHT WHEN SEAS COME UP SOME.
THE NEXT SURGE COMES WEDNESDAY AND WEDNESDAY NIGHT BEHIND A STRONG
COLD FRONT. MODERATE CHANCES FOR SMALL CRAFT ADVISORIES WITH THE
MID-WEEK SYSTEM.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR AMZ350-
374.
&&
$$
SYNOPSIS...
NEAR TERM...
SHORT TERM...JRL
LONG TERM...JRL
AVIATION...
MARINE...JRL
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
322 AM EST FRI FEB 21 2014
.SHORT TERM /TODAY THROUGH SATURDAY/...
MAIN FORECAST CONCERN THROUGH THE SHORT TERM CONTINUES TO BE THE
COLD FRONT PUSHING INTO NORTHWEST GEORGIA THIS MORNING. OVERALL
MODELS STILL CONSISTENT WITH THE TIMING OF THE SYSTEM THROUGH THE
AREA...AND FORECAST IS SKEWED TOWARDS HRRR AND LOCAL WRF FOR TIMING
OF THE FRONT PUSHING OUT OF THE CWA. ANTICIPATE THE BULK OF THE
ACTIVITY TO BE THROUGH THE ATL AREA 08-11Z...AND THROUGH THE MCN
AREA BY 11-13Z.
SEVERE POTENTIAL ENOUGH TO ISSUE SVR TSTM WATCH THROUGH SUNRISE. NAM
CONTINUES TO ADVERTISE THE HIGHER MUCAPE VALUES...WITH THE GFS STILL
AROUND 300-400J/KG AND MODELED LOW LEVEL SHEAR STILL IN THE 45-50KT
RANGE. OVERALL THE TORNADO THREAT IS MARGINAL AND IS EXPECTED
GRADUALLY LESSON THROUGH THE EARLY MORNING HOURS. THAT BEING
SAID...AN ISOLATED TORNADO CAN NOT BE RULED OUT ENTIRELY. A TORNADO
WATCH CONTINUES THROUGH 10Z FOR NORTHERN PORTIONS OF THE CWA. THE
MAIN CONCERN CONTINUES TO BE THE DAMAGING WINDS ASSOCIATED WITH THE
LINE GIVEN THE SUFFICIENT WIND SHEAR AND INSTABILITY. SOME ROTATION
HAS BEEN NOTED /ALBEIT BROAD/ IN THESE STORMS AS THEY HAVE MOVED
INTO THE STATE.
AS THE STORMS MOVE THROUGH...THE THREAT OF SEVERE ACTIVITY DROPS OFF
QUICKLY. LIGHT RAIN SHOWERS WILL PERSIST BEHIND THE MAIN LINE FOR A FEW
HOURS BEFORE CLEARING BEGINS.
WINDS ASSOCIATED WITH THE LINE WILL ALSO DIMINISH INTO THE DAYLIGHT
HOURS. GUSTY WINDS AHEAD OF THE FRONT AND THE DAMAGING WINDS
EMBEDDED WITHIN THE CONVECTION COULD BRING DOWN ALREADY WEAKENED
TREES ESPECIALLY VULNERABLE FROM THE RECENT ICE STORM.
QPF OF 1-1.25 INCHES WITH LOCALLY HIGHER AMOUNTS ACROSS NORTHWEST
GEORGIA COULD RESULT IN QUICKLY RISING CREEKS AND RIVERS.
BEHIND THE FRONT...HIGH PRESSURE BUILDING INTO THE REGION WILL KEEP
THE REMAINDER OF THE SHORT TERM DRY. LOOKING FOR HIGHS IN THE 60S
FRIDAY AND SATURDAY...WITH LOWS IN THE 30S SATURDAY MORNING.
31
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
THE OVERALL ACTIVE PATTERN CONTINUES INTO THE EXTENDED PERIOD. MODELS
CONTINUE TO SHOW NEARLY ZONAL FLOW ACROSS THE AREA INTO THE LONG
TERM. A WEAK UPPER LEVEL DISTURBANCE WITHIN THIS ZONAL FLOW
INTERACTS WITH AN OLD FRONTAL BOUNDARY ACROSS THE SOUTHERN PORTION
OF THE STATE. AS A RESULT...HAVE CONTINUED WITH THE SLIGHT CHANCE
TO CHANCE POPS SUNDAY...WITH THE BEST CHANCES FARTHER SOUTH. A
REINFORCING COLD FRONT PUSHES ACROSS THE AREA SUNDAY NIGHT INTO
MONDAY...WITH A DRY AND COOLER AIR MASS RETURNING TO THE STATE
MONDAY. BY MID WEEK...WEAK FRONTAL BOUNDARY MEANDERING ACROSS THE
STATE INTERACTS WITH THE FLOW ALOFT...BUT MODEL UNCERTAINTY STILL
HIGH ENOUGH TO JUST CONTINUE WITH SLIGHT CHANCES OF SHOWERS. WITH
LIMITED INSTABILITY AND WIND SHEAR...HAVE CONTINUED TO LEAVE OUT
MENTION OF THUNDERSTORMS AT THIS TIME.
39
&&
AVIATION...
06Z UPDATE...
LINE OF SHOWERS AND THUNDERSTORMS EXPECTED TO MOVE THROUGH THE
AREA OVERNIGHT...WITH DEGRADING CIGS AND VSBYS ACCOMPANYING THE
TSRA. HAVE TIMED THE SQUALL LINE THROUGH THE ATL AREA BY 10Z...AND
THE MCN AND AHN AREAS BY AROUND 12Z. S-SW GUSTY WINDS /15G25KT OR
SO/ WILL BECOME NW AT 13-15KT GUSTS TO 22-25KT BEHIND THE LINE.
EXPECT HIGH IFR OR LOW MVFR CIGS WITH THE POST-TSRA LIGHT
RAIN...WITH SLOW IMPROVEMENT THROUGH FRIDAY MORNING...AND VFR BY AFTERNOON.
//ATL CONFIDENCE...06Z UPDATE...
MEDIUM CONFIDENCE ON ALL ELEMENTS.
31
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 63 36 68 40 / 100 5 5 10
ATLANTA 61 39 66 43 / 80 5 5 10
BLAIRSVILLE 57 32 63 36 / 70 5 5 10
CARTERSVILLE 61 32 66 38 / 60 5 5 10
COLUMBUS 63 39 67 41 / 100 5 5 20
GAINESVILLE 62 38 65 40 / 100 5 5 10
MACON 64 34 68 40 / 100 5 5 10
ROME 60 31 65 36 / 40 5 5 10
PEACHTREE CITY 61 30 66 36 / 90 5 5 10
VIDALIA 68 45 70 46 / 100 10 5 10
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
SEVERE THUNDERSTORM WATCH UNTIL 9 AM EST THIS MORNING FOR THE
FOLLOWING ZONES: CARROLL...CHATTAHOOCHEE...CLAYTON...COBB...
COWETA...DEKALB...DOUGLAS...FAYETTE...GWINNETT...HARALSON...
HARRIS...HEARD...HENRY...MARION...MERIWETHER...MUSCOGEE...NORTH
FULTON...PAULDING...PIKE...POLK...ROCKDALE...SCHLEY...SOUTH
FULTON...SPALDING...STEWART...SUMTER...TALBOT...TAYLOR...TROUP...
UPSON...WEBSTER.
TORNADO WATCH UNTIL 5 AM EST EARLY THIS MORNING FOR THE
FOLLOWING ZONES: BARTOW...CATOOSA...CHATTOOGA...CHEROKEE...
DADE...DAWSON...FANNIN...FLOYD...FORSYTH...GILMER...GORDON...
HALL...LUMPKIN...MURRAY...PICKENS...TOWNS...UNION...WALKER...
WHITE...WHITFIELD.
&&
$$
SHORT TERM...31
LONG TERM....39
AVIATION...31
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
849 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 03Z...
* NONE.
RC
//DISCUSSION...UPDATED 00Z...
NO SIGNIFICANT AVIATION CONCERNS AT THE TAF SITES FOR THE NEXT
24-30 HOURS...WITH VFR CONDITIONS AND GENERALLY WESTERLY WINDS.
GUSTS COULD APPROACH 20 KT SUNDAY AFTERNOON INTO SUNDAY EVENING.
RC
//ORD AND MDW CONFIDENCE...UPDATED 03Z...
* HIGH FOR ALL ELEMENTS.
RC
//OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z...
MONDAY...VFR LIKELY DURING DAYTIME THEN LIGHT SNOW BECOMING
LIKELY MONDAY NIGHT WITH MVFR LIKELY...IFR POSSIBLE.
TUESDAY...CHANCE OF LIGHT SNOW EARLY AM. THEN VFR LIKELY.
WEDNESDAY THROUGH FRIDAY...VFR LIKELY.
RC
&&
.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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[top]
Area Forecast Discussion
National Weather Service Lincoln IL
636 PM CST Sat Feb 22 2014
.DISCUSSION...
ISSUED 636 PM CST Sat Feb 22 2014
Made a few quick updates to the forecast to better reflect current
trends, mainly to tighten the POP gradient across central Illinois.
Radar continues to indicate the narrow band of precipitation
remaining focused along a Jacksonville to Danville line. Latest
run of the HRRR shows very little movement of the band until 04z
when it slowly sinks southeastward. As a result, have increased
POPs to categorical within the band itself and have removed all
mention of POPs further north in the Peoria area and further south
from Effingham southward. With surface temps in the middle to
upper 30s initially, precip has started as rain at most sites, but
is quickly transitioning to wet snow as evaporative cooling takes
place within the surface-based layer. Based on gradual eastward
shift of precip area and current temps above freezing, think snow
accumulations will remain light. 1 to 2 inches still look reasonable
across the E/NE KILX CWA, mainly from Decatur northeastward
through Champaign to Danville, with little or no accumulation
elsewhere around the area. Zone update has already been issued.
Barnes
&&
.AVIATION...
ISSUED 551 PM CST Sat Feb 22 2014
Narrow band of precipitation has developed just north of a nearly
stationary frontal boundary late this afternoon. High-res models
such as the HRRR suggest that this band will remain focused along
a KSPI to KDEC to KCMI line for the next 3 to 4 hours before
gradually diminishing/shifting eastward into Indiana. Radar trends
seem to be following this forecast quite nicely thus far. As a
result, have kept both KPIA and KBMI dry. Further south at the
remaining terminals, light precip will start as rain then slowly
mix with and change to snow before ending. Lowest ceilings/visbys
associated with snow will likely be noted across the E/NE CWA, so
have gone with IFR conditions at KCMI. After 05z, precip will push
into Indiana, leaving behind mostly cloudy and dry conditions
through the remainder of the 00z TAF period.
Barnes
&&
.PREV 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.
Barnes
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
535 AM CST FRI FEB 21 2014
.DISCUSSION...
305 AM CST
TODAY...
POWERFUL STORM SYSTEM CONTINUES TO INFLUENCE THE WEATHER FOR THE
REGION TODAY...DESPITE THE SFC LOW BECOMING CENTERED WELL NORTH OF
THE FORECAST AREA THIS MORNING OVER NORTHERN WISCONSIN. A VERY TIGHT
GRADIENT REMAINS OVER NORTHERN IL/NORTHWEST IN...AS EARLY THIS
MORNING ISALLOBARIC PRES RISES HOVER ARND 5MB/3HR. THIS HAS BEEN
PRODUCING SUSTAINED WINDS BETWEEN 20-30MPH AND GUSTS AT TIMES TO 45
MPH. WILL MAINTAIN THE CURRENT WIND ADVISORY...HOWEVER BASED ON
LATEST GUIDANCE IT APPEARS GUSTS MAY BEGIN TO DIMINISH CLOSER TO
MIDDAY.
IR IMAGERY INDICATES THE DRY WEDGE HAS DEPARTED TO THE
NORTHEAST...WITH THE WRAP-AROUND MOISTURE BEGINNING TO SLIDE BACK
INTO NORTHERN IL/NORTHWEST IN. SFC OBS UPSTREAM EARLY THIS MORNING
HAVE INDICATED SOME LIGHT SNOW...AND A FEW POINTS IN CENTRAL IOWA
HAD VSBYS DOWN TO 1/4 MILE WITH MODERATE SNOW...HOWEVER FEEL THIS
MAY HAVE ACTUALLY BEEN A FUNCTION OF THE VERY GUSTY WINDS AND
AMPLIFYING THE EFFECTS SLIGHTLY. OVERALL THOUGH EXPECT THIS
WRAP-AROUND WEDGE TO SLOWLY SLIDE NORTHEAST...CLIPPING NORTHERN IL
THIS MORNING. THIS MAY PRODUCE A DUSTING OF SNOW...OTHERWISE BY LATE
MORNING FLURRIES SHOULD BE ALL THAT REMAINS BEFORE ENDING EARLY THIS
MORNING. TEMPS TODAY WILL BE CHAOTIC...WITH MORNING TEMPS MAINLY IN
THE 30S ACROSS THE REGION THEN FALLING INTO THE 20S. WITH CLOUD
COVER ERODING BY EARLY AFTN FROM SOUTHWEST TO NORTHEAST...THIS MAY
ALLOW TEMPS TO REBOUND A FEW DEGREES THIS AFTN. SO AS A RESULT HAVE
HELD ONTO HIGHS IN THE LOW/MID 30S WITH NEAR 40 ALONG THE FAR
SOUTHERN CWFA.
CONFIDENCE...HIGH.
TONIGHT THROUGH SUNDAY...
500MB TROUGH AXIS RETURNS TO THE REGION...WHICH PLACES A HOLD ON THE
PAST FEW DAYS OF ABNORMALLY WARM TEMPS AND BRINGS A REALITY CHECK
THAT WINTER IS STILL THE PREFERRED SEASON OF CHOICE BY MOTHER
NATURE. WITH THE POWERFUL SHORTWAVE STEADILY LIFTING NORTHEAST
TOWARDS JAMES BAY TONIGHT...THE TRAILING GRADIENT WILL WEAKEN. BROAD
SFC RIDGING IS POISED TO SLIDE EAST ACROSS THE TENN VALLEY
STRETCHING SOUTH TO THE GULF OF MEXICO. THIS WILL ALLOW THE FLOW
OVER OUR REGION TO MAINLY BE WESTERLY THROUGH TONIGHT AND INTO
SATURDAY.
GUIDANCE DIFFERS ON HOW TO RESOLVE A WEAK MID-LVL LOBE OF VORTICITY
THAT WILL MOVE EAST ACROSS THE CENTRAL PLAINS TOWARDS THE OHIO
VALLEY. THE FORCING LOOKS RATHER LOW WITH THIS FEATURE...HOWEVER A
SECONDARY SFC RIDGE OVER THE NORTHERN PLAINS WILL STRETCH SOUTHEAST
TOWARDS THE FORECAST AREA SAT NGT. AT THIS TIME HAVE HELD ONTO A DRY
FORECAST...HOWEVER COULD SEE FLURRIES BEING NEEDED AND PERHAPS A
SMALL WINDOW OF LIGHT SNOW SHOWERS INTO EARLY SUN MORNING.
THE 500MB TROUGH DOES NOT INDICATE ANY AMPLIFICATION THROUGH THE
WEEKEND...WHICH WILL LIKELY MAINTAIN A SEMI-ZONAL FLOW. THIS WILL
EXPEDITE PACIFIC WAVES REACHING THE FORECAST AREA/OHIO VALLEY IN AN
EFFICIENT MANNER. AS A RESULT GUIDANCE CONTINUES TO SUGGEST YET
ANOTHER WEAK MID-LVL LOBE OF VORTICITY ARRIVING SUN AFTN.
TEMPS TONIGHT WILL FALL INTO THE TEENS TO MID 20S...THEN WITH
P-CLOUDY SKIES SAT AND 850MB TEMPS HOVERING ARND -4 TO -6 DEG
C...HIGHS SAT SHOULD GENERALLY BE IN THE LOW 30S...POSSIBLY NEAR 40
FOR THE FAR SOUTHERN CWFA. WEAK FRONTAL BOUNDARY SLIDES OVER THE
AREA SUN...WITH WINDS TURNING NORTHWESTERLY AND BRINGING SLIGHTLY
COOLER AIR AS HIGHS ARE GENERALLY IN THE 20S.
CONFIDENCE IN TEMPS...MEDIUM/HIGH.
CONFIDENCE IN FLURRIES/LGT SNOW...MEDIUM.
MONDAY THROUGH FRIDAY...
ENSEMBLES HAVE CONTINUED TO POINT TOWARDS YET ANOTHER PATTERN CHANGE
BREWING IN THE EXTENDED PERIODS...WITH A HIGH-AMPLITUDE RIDGE
DEVELOPING OVER WESTERN CANADA OR THE YUKON. THE DOWNSTREAM RESULT
IS YET ANOTHER DEEP TROUGH DIGGING SOUTH THROUGH THE GREAT LAKES
REGION.
A WEAK MID-LVL WAVE WILL TRAVERSE THE REGION MON...WITH A PERIOD OF
LIGHT SNOW PROGGED TO BLANKET THE CWFA. THEN MOVING INTO TUE/WED...A
STRONGER FRONTAL BOUNDARY IS POISED TO SLIDE SOUTHEAST FROM CANADA
AND BRING 850MB THERMAL TROUGH OF -14 TO -20 DEG C TO THE REGION BY
WED...HOWEVER THIS MAY BE MILD COMPARED TO THE LATER PERIODS WHEN
GUIDANCE IS CURRENTLY SUGGESTING 850MB TEMPS BY LATE NEXT WEEK IN
THE -23 TO -28 DEG C RANGE. THIS WILL LIKELY ALLOW SFC TEMPS FOR THE
MIDDLE OF NEXT WEEK TO REMAIN IN THE TEENS...THEN POSSIBLY STRUGGLE
TO WARM BEYOND THE SINGLE DIGITS ABOVE ZERO BY THUR OF NEXT WEEK.
CONFIDENCE...HIGH.
BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 12Z...
* VERY GUSTY WESTERLY WINDS.
* MVFR CIGS IMPROVING TO VFR LATE MORNING/EARLY AFTERNOON.
* LIGHT SNOW EARLY TO MID MORNING...WITH BLOWING SNOW.
BMD
//DISCUSSION...UPDATED 12Z...
A DEEP AREA OF LOW PRESSURE CURRENTLY OVER FAR NORTHERN WISCONSIN
CONTINUES TO LIFT AWAY FROM THE AREA...BUT STRONG WESTERLY WINDS ARE
FORECAST TO PERSIST MUCH OF THE DAY WITH GUSTS IN THE MID TO UPPER
30 KT RANGE THROUGH THE AFTERNOON...TAPERING INTO THE HIGH 20 TO LOW
30 KT RANGE THIS EVENING. MEANWHILE...AN UPPER LEVEL DISTURBANCE IS
DROPPING SOUTHEAST ACROSS THE MID/UPPER MISSISSIPPI VALLEY EARLY
THIS MORNING WITH SNOW SPREADING ACROSS NORTHERN ILLINOIS. VSBY IS
FALLING INTO THE 1-2SM RANGE AT TIMES WITH THE SNOW AND BLOWING
SNOW. THE WAVE SHOULD PASS WITH PRECIP ENDING MID TO LATE THIS
MORNING...AND WE MAY SEE LIGHT ACCUMULATIONS OF A FEW TENTHS. MVFR
CIGS WILL PERSIST THIS MORNING...BUT DRIER AIR MOVING IN SHOULD
SCOUR OUT SOME OF THE LOWER CLOUDS BY EARLY AFTERNOON WITH
CONDITIONS BECOMING VFR. WINDS WILL EASE THIS EVENING AND
TONIGHT...AND SHOULD REMAIN SW TO W.
BMD
//ORD AND MDW CONFIDENCE...UPDATED 12Z...
* HIGH CONFIDENCE IN WIND DIRECTION...MEDIUM-HIGH CONFIDENCE IN
SPEED.
* MEDIUM-HIGH CONFIDENCE IN CIG TRENDS...MEDIUM IN TIMING
IMPROVEMENT TO VFR.
* LOW CONFIDENCE IN HOW AREAS OF SNOW WILL EVOLVE OVERNIGHT.
BMD
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
SATURDAY NIGHT THROUGH SUNDAY...VFR.
MONDAY...CHC SNOW...ESPECIALLY LATE.
TUESDAY THROUGH THURSDAY...VFR.
BMD
&&
.MARINE...
302 AM CST
STRONG LOW PRESSURE LIES OVER WISCONSIN EARLY THIS MORNING AND WILL
LIFT NORTH ACROSS ONTARIO TO JAMES BAY BY LATE TONIGHT.
MEANWHILE...A TIGHT PRESSURE GRADIENT WILL RESULT IN STRONG GALES
AND STORM FORCE WINDS AT TIMES ACROSS LAKE MICHIGAN THROUGH THIS
AFTERNOON. WILL LEAVE THE CURRENT TIMING IN PLACE FOR THE STORM
WARNING...THOUGH LATEST PROJECTIONS INDICATE THAT IT MAY BE
CANCELED EARLY. EITHER WAY...A GALE WARNING WILL BE NEEDED TO
REPLACE THE STORM WARNING FOR A PERIOD LATE THIS AFTERNOON INTO
THE EARLY OVERNIGHT HOURS. WINDS SHOULD FINALLY DIMINISH BELOW
GALES LATE TONIGHT BUT WILL REMAIN AROUND 30 KT THROUGH THE
REMAINDER OF THE WEEKEND. A BROAD RIDGE OF HIGH PRESSURE WILL
BUILD FROM THE NORTHERN PLAINS INTO THE OHIO VALLEY AND REMAIN
ANCHORED FOR MUCH OF THE UPCOMING WEEK...LEAVING LAKE MICHIGAN
WITH PERSISTENT MODERATE WEST TO NORTHWEST WINDS NEXT WEEK.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...WIND ADVISORY...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-ILZ011-
ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022-ILZ023-
ILZ032-ILZ033-ILZ039 UNTIL 3 PM FRIDAY.
IN...WIND ADVISORY...INZ001-INZ002-INZ010-INZ011-INZ019 UNTIL 3 PM
FRIDAY.
LM...STORM WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 3 PM FRIDAY.
GALE WARNING...NEARSHORE WATERS UNTIL 6
PM FRIDAY.
&&
$$
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Area Forecast Discussion
National Weather Service Lincoln IL
350 AM CST Fri Feb 21 2014
.DISCUSSION...
ISSUED 323 AM CST Fri Feb 21 2014
Dynamic storm system moved through the region yesterday and
overnight with the main cold front well out to the east and the
occluded low center over nrn Wisconsin this morning. A small wave
rippling around this morning in the wake of the cold front
bringing some light snow and may continue through the morning
hours. Other than that, forecast is mainly a slow chill beyond
today and tomorrow as another push of cold air comes to the
Midwest. As far as precipitation, several shortwaves are hinted in
the models, but timing is not very consistent. Best consistency is
for Monday/Monday night, with the chance for accumulating snow.
Beyond Monday, temperatures fall below normals in the extended for
next week. At this point the forecast in the extended is dry, but
as it is also increasingly NWrly flow, expect to eventually see a
couple of short waves creep into the forecast.
SHORT TERM...Today and tomorrow...
A short break in the frigid temperatures as the max temps will
climb above freezing heading into the weekend. Clearing this
morning should result in a sunny afternoon, but clouds redevelop
for tomorrow so partly cloudy skies will keep temps from
increasing too much over todays max. Tonight and tomorrow night, a
quick shot for snow across the northern tier of the CWA as
shortwaves ripple through in the wake of the exiting low. Both
shots at precip should result in less than a half of an inch of
accumulation.
LONG TERM...Sunday through Thursday...
Relatively dry but beyond the weekend the operational models are
shearing out some energy across the center of the country and
setting up a weak boundary in parallel flow. Agreement btwn GFS
and ECMWF for the existence of a Monday/Monday night system, with
major issues with the timing. At the end of the NAM run, but the
NAM is leaning into the same solution. Just another quick shot of snow
with a clipper-like system from the WNW. Colder air moving in as
well, as flow amplifies and Midwest sees northwesterly flow
reestablish Tuesday night/Wednesday. Temperatures from midweek on
drop below seasonal normals again.
HJS
&&
.AVIATION...
ISSUED 1139 PM CST Thu Feb 20 2014
Strong W/SW winds will continue through the overnight hours,
although they will not be quite as strong as earlier this
evening. Based on latest obs and 00z numeric guidance, have
lowered winds into the 15 to 20kt range with gusts to between 25
and 30kt. The strong/gusty winds will continue through Friday as
well, before subsiding to around 10kt by evening. Main aviation
challenge will be an area of MVFR clouds currently pushing
eastward across Iowa/northern Missouri. Satellite timing tools
bring these clouds into KSPI by 08z, then further east to KCMI
between 09z and 10z. HRRR does not have a good handle on the
clouds, but at least hints at ceilings overnight into early Friday
morning. Have therefore cleared skies from west to east between
12z and 14z.
Barnes
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
303 AM CST FRI FEB 21 2014
.DISCUSSION...
311 PM CST
THIS EVENING WILL SEE A QUICK TRANSITION FROM DENSE FOG TO BRIEFLY
HEAVY RAIN WITH THUNDERSTORMS...TO RAPIDLY FALLING TEMPERATURES AND
VERY STRONG WIND GUSTS. NOT SURE ABOUT EXACT TIMING OF BETTER
VISIBILITIES THIS EVENING...SO WILL MAINTAIN THE DENSE FOG ADVISORY
THROUGH 01Z BUT EXPECT SOUTHERN AREAS MAY CLEAR EARLIER THAN THAT.
VERY DENSE FOG WITH VISIBILITIES OF 1/4 MILE OR LESS IS BEING
REPORTED AT SEVERAL OBSERVATION SITES...AND LOWER VALUES ARE LIKELY
OUT THERE SOMEWHERE.
LATER THIS EVENING MODEL GUIDANCE AND UPSTREAM OBSERVATIONS BOTH
CONTINUE TO SUPPORT THE POTENTIAL FOR NON CONVECTIVE GUSTS IN
EXCESS OF 50 MPH FOR AT LEAST A WHILE AS THE COLD FRONT PUSHES
THROUGH.
LASTLY...THE FLOOD WATCH WAS ALLOWED TO EXPIRE AT 3 PM CST AFTER
THE BREAK IN THE AFTERNOON SHOWERS. SNOWMELT DOES CONTINUE AND
UPSTREAM STORMS MAY YET PRODUCE HEAVY RAIN...BUT THE STORMS SHOULD
BE VERY LOCALIZED AND RELATIVELY BRIEF. TEMPERATURES FALLING BELOW
FREEZING LATER THIS EVENING WOULD HELP TO FURTHER MITIGATE THE
DEGREE OF SNOWMELT.
LENNING
OVERNIGHT THROUGH THURSDAY...
AS COLDER AIR SPREADS ACROSS THE REGION BEHIND THE COLD FRONT...A
PERIOD OF LIGHT SNOW WILL BE POSSIBLE ESPECIALLY ACROSS THE
NORTHERN THIRD/HALF OF THE CWA. WITH ONLY A FEW HUNDREDTHS OF
QPF...SNOWFALL AMOUNTS WILL BE LIGHT A DUSTING TO PERHAPS A HALF
INCH. BUT WITH THE STRONG/GUSTY WINDS...ANY AMOUNT OF SNOWFALL
COULD CAUSE BLOWING AND DRIFTING SNOW. HAVE INCREASED POPS TO
LIKELY ACROSS THE NORTH OVERNIGHT BUT THESE MAY NEED TO GO HIGHER
AND PERHAPS BE EXTENDED INTO FRIDAY MORNING...ESPECIALLY FOR FAR
NORTHEAST IL. TEMPS WILL FALL THROUGH THE 20S AND COMBINED WITH
THE STRONG WINDS...WIND CHILLS IN THE SINGLE DIGITS ARE EXPECTED
BY FRIDAY MORNING.
A BRIEF PERIOD OF WEAK WARM AIR ADVECTION WILL OCCUR FRIDAY
AFTERNOON INTO FRIDAY EVENING AND THIS COMBINED WITH AT LEAST
PARTLY CLOUDY SKIES SHOULD HELP TEMPERATURES REBOUND INTO THE
LOWER/MID 30S NORTH TO UPPER 30S/NEAR 40 SOUTH. A COLD FRONT WILL
THEN MOVE ACROSS THE AREA FRIDAY NIGHT AND THERE REMAINS SOME
POTENTIAL FOR LIGHT SNOW OR SNOW SHOWERS AND HAVE INTRODUCED LOW
CHANCE POPS BACK INTO THE FORECAST FOR THIS TIME PERIOD. FLOW
REMAINS SOMEWHAT ZONAL SATURDAY WITH NO SIGNIFICANT COOLING BEHIND
THE FRONT...SO HIGHS SATURDAY COULD BE SIMILAR TO HIGHS ON FRIDAY.
BY SUNDAY MORNING...ANOTHER WEAK WAVE WILL QUICKLY MOVE ACROSS THE
REGION WITH A PERIOD OF LIGHT SNOW ASSOCIATED WITH IT. WHERE IT
MOVES/DEVELOPS REMAINS SOMEWHAT UNCERTAIN BUT THE NORTHERN EXTENT
OF IT MAY SPREAD ACROSS THE SOUTHERN CWA AND HAVE INCLUDED LOW
CHANCE POPS FOR THIS PERIOD.
FROM SUNDAY THROUGH THURSDAY...THE TREND WILL BE COLDER WITH HIGHS
ONLY IN THE 20S AND LOWS IN THE SINGLE DIGITS...AND THAT IS BEFORE
THE NEXT PUSH OF ARCTIC AIR ARRIVES WEDNESDAY/WEDNESDAY NIGHT. BY
THIS TIME...OVERNIGHT LOWS WILL LIKELY DROP INTO SINGLE DIGITS BELOW
ZERO WITH DAYTIME HIGHS BY THURSDAY MAYBE ONLY LOWER TEENS/SINGLE
DIGITS.
ONE OTHER CONCERN IN THE EXTENDED WOULD BE A CLIPPER SYSTEM TO
AFFECT THE REGION MONDAY AFTERNOON INTO MONDAY NIGHT. THIS HAS BEEN
A FAIRLY CONSISTENT FEATURE ON THE GFS/ECMWF FOR SEVERAL RUNS AND
SEEMS TO MOVE RIGHT ACROSS THE CWA BUT NOW IN A WEAKENING FORM. THIS
STILL APPEARS TO HAVE THE POTENTIAL TO PRODUCE A FEW INCHES OF
FLUFFY SNOW BUT HAVE ONLY BUMPED POPS INTO MID CHANCE RANGE FOR NOW.
CMS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 09Z...
* VERY GUSTY WESTERLY WINDS.
* MVFR CIGS IMPROVING TO VFR LATE FRIDAY MORNING/EARLY AFTERNOON.
* CHANCE FOR SOME ADDITIONAL LIGHT SNOW SHOWERS EARLY TO MID
FRIDAY MORNING...WITH BLOWING SNOW.
BMD
//DISCUSSION...UPDATED 06Z...
DEEP AREA OF LOW PRESSURE WILL CONTINUE TO LIFT ACROSS WISCONSIN
OVERNIGHT WITH A TIGHT PRESSURE GRADIENT AND STRONG PRESSURE RISES
ACROSS NORTHERN ILLINOIS RESULTING IN STRONG WESTERLY WINDS. WIND
ARE EXPECTED TO CONTINUE TO GUST IN THE MID TO UPPER 30 KT RANGE
OVERNIGHT THROUGH FRIDAY AFTERNOON...THEN SHOULD BEGIN TO TAPER
LATE AFTERNOON INTO THE EVENING AS THE GRADIENT SLACKENS.
CIGS ACROSS THE REGION ARE GENERALLY 015-025 TONIGHT AND EXPECT
THESE LEVELS TO PERSIST OVERNIGHT. ANOTHER WAVE CURRENTLY OVER
IOWA WILL MOVE ACROSS THE TERMINALS EARLY TO MID MORNING BRING
ADDITIONAL LIGHT SNOW SHOWERS. MOISTURE IS FAIRLY SHALLOW THOUGH
AND SOME MODELS MAINTAIN DRY CONDITIONS IN THE MORNING. WILL HAVE
TO MONITOR UPSTREAM TRENDS AND MAY BE ABLE TO PULL MENTION OF
SNOW/BLOWING SNOW IF THIS OCCURS. OTHERWISE...GIVEN THE STRONG
WINDS...EXPECT EVEN LIGHT SNOW TO BLOW AROUND RESULTING IN MORE
SIGNIFICANT REDUCTIONS IN VISIBILITY THAN OTHERWISE WOULD BE
EXPECTED.
BMD
//ORD AND MDW CONFIDENCE...UPDATED 09Z...
* HIGH CONFIDENCE IN WIND DIRECTION...MEDIUM-HIGH CONFIDENCE IN
SPEED.
* MEDIUM-HIGH CONFIDENCE IN CIG TRENDS...MEDIUM IN TIMING
IMPROVEMENT TO VFR.
* LOW CONFIDENCE IN HOW AREAS OF SNOW WILL EVOLVE OVERNIGHT.
BMD
//OUTLOOK FOR ORD/MDW FOR 12Z SATURDAY-12Z THURSDAY...UPDATED 00Z...
SATURDAY...VFR.
SUNDAY...VFR.
MONDAY...SLIGHT CHANCE OF LIGHT SNOW DURING THE AFTERNOON AND
NIGHT OTHERWISE VFR.
TUESDAY...VFR.
WEDNESDAY...VFR.
ED F
&&
.MARINE...
302 AM CST
STRONG LOW PRESSURE LIES OVER WISCONSIN EARLY THIS MORNING AND WILL
LIFT NORTH ACROSS ONTARIO TO JAMES BAY BY LATE TONIGHT.
MEANWHILE...A TIGHT PRESSURE GRADIENT WILL RESULT IN STRONG GALES
AND STORM FORCE WINDS AT TIMES ACROSS LAKE MICHIGAN THROUGH THIS
AFTERNOON. WILL LEAVE THE CURRENT TIMING IN PLACE FOR THE STORM
WARNING...THOUGH LATEST PROJECTIONS INDICATE THAT IT MAY BE
CANCELED EARLY. EITHER WAY...A GALE WARNING WILL BE NEEDED TO
REPLACE THE STORM WARNING FOR A PERIOD LATE THIS AFTERNOON INTO
THE EARLY OVERNIGHT HOURS. WINDS SHOULD FINALLY DIMINISH BELOW
GALES LATE TONIGHT BUT WILL REMAIN AROUND 30 KT THROUGH THE
REMAINDER OF THE WEEKEND. A BROAD RIDGE OF HIGH PRESSURE WILL
BUILD FROM THE NORTHERN PLAINS INTO THE OHIO VALLEY AND REMAIN
ANCHORED FOR MUCH OF THE UPCOMING WEEK...LEAVING LAKE MICHIGAN
WITH PERSISTENT MODERATE WEST TO NORTHWEST WINDS NEXT WEEK.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...WIND ADVISORY...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-ILZ011-
ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022-ILZ023-
ILZ032-ILZ033-ILZ039 UNTIL 3 PM FRIDAY.
IN...WIND ADVISORY...INZ001-INZ002-INZ010-INZ011-INZ019 UNTIL 3 PM
FRIDAY.
LM...STORM WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 3 PM FRIDAY.
STORM WARNING...NEARSHORE WATERS UNTIL
4 AM FRIDAY.
&&
$$
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Area Forecast Discussion
National Weather Service Lincoln IL
1139 PM CST Thu Feb 20 2014
.DISCUSSION...
ISSUED 847 PM CST Thu Feb 20 2014
Cold front and associated convection has now pushed well to the
east into Indiana, leaving behind windy and cooler conditions
across central Illinois. Latest obs generally show winds in the 25
to 35 mph range, with gusts occasionally over 40 mph. Will
continue with the High Wind Warning at this time, but this may
need to be canceled early as upstream winds across Missouri have
weakened even further. Made some minor adjustments to hourly temp
grids to account for the colder air spilling into the region, but
changes do not effect the going forecast. Therefore no zone update
is needed at this time.
Barnes
&&
.AVIATION...
ISSUED 1139 PM CST Thu Feb 20 2014
Strong W/SW winds will continue through the overnight hours,
although they will not be quite as strong as earlier this
evening. Based on latest obs and 00z numeric guidance, have
lowered winds into the 15 to 20kt range with gusts to between 25
and 30kt. The strong/gusty winds will continue through Friday as
well, before subsiding to around 10kt by evening. Main aviation
challenge will be an area of MVFR clouds currently pushing
eastward across Iowa/northern Missouri. Satellite timing tools
bring these clouds into KSPI by 08z, then further east to KCMI
between 09z and 10z. HRRR does not have a good handle on the
clouds, but at least hints at ceilings overnight into early Friday
morning. Have therefore cleared skies from west to east between
12z and 14z.
Barnes
&&
.PREV DISCUSSION...
ISSUED 320 PM CST Thu Feb 20 2014
Short term issues revolve around a rapidly deepening low pressure
system passing across far NW IL this afternoon, with a cold front
racing across IL and into Indiana by 7 pm. Severe weather
potential will progress east along and south of the warm front.
Areas of very dense fog should dissipate behind the cold front as
well.
Very strong winds will develop as pressure rises reach 12mb per 3
hours. Wind speeds of 30-40 mph and gusts over 55 mph will develop
shortly after the cold front passes. Flooding is already occurring
across Knox and Stark counties where 2-2.5" of rain already fell
earlier today. More rain from the line of thunderstorms could
aggravate the flooding.
Beyond the very busy short term, we have various short waves
expected to move across IL between Friday night and Monday night.
With the colder air also arriving this weekend, most of any
precipitation that does develop should fall as snow. The models
are producing widely varying solutions as to amount and coverage
of any precip during that time, but we wanted to at least
acknowledge the potential for precip due to at least 2 models
showing some precipitation produced by each wave.
SHORT TERM...Tonight through Sunday.
A line of storms will race across IL just ahead of the cold front.
Forward motion of the storms is being measured at 60 mph, with a
low level jet of 70 kts just above the LCL. Storms are moving from
to the N-NE towards areas with snow cover and more stable air near
the ground. We expect to see localized damaging winds from the
storm gust fronts in areas along and south of the warm front,
which generally extends from Galesburg to Bloomington at this
point. Isolated tornadoes could develop as wind shear rapidly
increases just ahead of the cold front.
As storms move farther north over snow covered areas, storms should
begin to lose the ability to blast damaging winds through the
stable low level airmass to the ground. The severe thunderstorm
watch goes until 6 pm for out SW counties, but an additional watch
will likely be needed farther east and south of the warm front as
the cold front moves across IL.
Dense fog has caused travel hazards for areas north of Rushville
to Lincoln to Bloomington, and a dense fog advisory will go
through 6 pm.
Shortly behind the cold front, very strong pressure rises will
produce very strong winds for several hours, with the strongest
gusts possibly as high as 60 mph in the first 3-4 hours behind the
front. Pressure rises diminish somewhat later this evening, but
sustained winds will likely remain around 30 mph gusting to 40 mph
at times until midnight. We may be able to remove some of the
wind warning headline a little before 3 am as conditions warrant.
A band of light rain or snow may move into our west-northwestern
counties this evening through just after midnight, but little to
no snow accumulation is expected.
The axis of coldest air behind the cold front will pass across our
forecast area around 12z/6am Friday morning. Clouds will begin to
clear out of our SW areas around that time, but lows should still
remain in the mid 20s north and upper 20 south. Warming occurs
through the day on Friday, as 850mb temps climb from -8C or -9C at 6
am to zero to -2C at 6 pm. West-southwest winds will remain brisk
and help to push high temps into the 40s across the board.
The first shortwave that could produce some light snow is forecast
to arrive Friday night. The GFS and Canadian have been
consistently showing that feature and a dusting to a half inch of
snow across the northern counties. The 12z Canadian did back off a
little on the QPF, but the 12z ECMWF has started pointing towards
forcing for precip during that time over that area as well.
The airmass cools down for Saturday, as high pressure builds into
IL from the NW. The GFS and Canadian once again team up on a
shortwave for Sunday, producing 0.5" to 1" of snow across our W
and N counties. The NAM indicates some snow for our southeastern
counties Sunday afternoon, while the ECMWF is not resolving that
feature as well.
More noticeably cooler highs are forecast for Sunday as readings
top out about 10-12F degrees colder than Saturday.
LONG TERM...Monday through Thursday.
The third shortwave is projected to arrive later Monday morning or
Monday afternoon. There is some agreement on this by the GFS,
Canadian, and ECMWF. With 3 models in general agreement, we
increased PoPs into the chance category across the north, for
another 0.5 to 1" of snow through early Monday evening.
A stronger push of cold air will arrive behind that wave, as 850mb
temps drop to -16C to -18C by Tuesday evening. Lows should reach
into the single digits above zero north of Peoria to Bloomington
Tues night, with single digits N of I-70 Wed night. The coldest
highs this week look to be on Thursday as readings remain in the
teens north of a line from Rushville to Champaign.
Light snow may return late next Thursday afternoon and Thursday
night as yet another shortwave pushes into the area.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY until 3 AM CST Friday FOR ILZ027>031-036>038-
040>057-061>063-066>068-071>073.
&&
$$
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
705 PM EST SAT FEB 22 2014
.SYNOPSIS...
ISSUED AT 608 PM EST SAT FEB 22 2014
SNOW WILL BE POSSIBLE OVERNIGHT MAINLY NEAR AND SOUTH OF HIGHWAY
24. ANY MIXED PRECIPITATION WILL QUICKLY CHANGE OVER TO ALL SNOW
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 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 702 PM EST SAT FEB 22 2014
CONCERN LIES WITH FINE LINE MESOSCALE BANDED PRECIPITATION ALONG
AND NORTH OF RESPONSE TO INTENSE 850-800MB FRONTOGENETIC AXIS
EMENATING FM WCNTL IL INTO NWRN OH. KFWA SHOULD REMAIN ON NRN
MOST EDGE OF ENHANCED PRECIP ASSOCD WITH THIS FEATURE OVR THE
NEXT FEW HOURS...BEFORE A MORE VEERED PROFILE BECOMES
ESTABLISHED. PTYPE MAY MIX BRIEFLY RA/FZRA/PL...THOUGH PRIMARILY
SN ANTICIPATED WITH TEMPO IFR VSBYS/FUELING RQRMNTS/PRECLUDING AS
ALT TIL 02 UTC. THEREAFTER...WL CONT IMPROVING TREND AS
SUCCINCT/STRONG 130 KT 4-3.5H JETLET PRESENTLY ACRS SRN LWR
MI...AND FOCUS OF INTENSE/DEEP DIVERGENT SIGNAL...SLIDES EWD INTO
LWR GRTLKS LATER THIS EVENING.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SYNOPSIS...KG
SHORT TERM...LASHLEY
LONG TERM...SKIPPER
AVIATION...MURPHY
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.TWITTER.COM/NWSIWX
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AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
608 PM EST SAT FEB 22 2014
.SYNOPSIS...
ISSUED AT 608 PM EST SAT FEB 22 2014
SNOW WILL BE POSSIBLE TONIGHT MAINLY NEAR AND SOUTH OF HIGHWAY 24.
ANY LIQUID PRECIPITATION WILL QUICKLY CHANGE OVER TO ALL SNOW 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/KG
SHORT TERM...LASHLEY
LONG TERM...SKIPPER
AVIATION...LASHLEY
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AREA FORECAST DISCUSSION
NWS DODGE CITY KS
510 PM CST Sat Feb 22 2014
...Updated aviation discussion...
.SHORT TERM...(This evening through Sunday)
ISSUED AT 128 PM CST SAT FEB 22 2014
Tonight:
Northeasterly to easterly low level upslope flow is expected through
the overnight hours. This will result in the formation of stratus across
the region after midnight. Any precipitation is expected to remain north
of the region in association with a 700 hPa baroclinic zone. Will stick
with silent pop probabilities for now. Do have very high cloud cover
in the grids in anticipation of the stratus. The saturated layer does
not look thick enough for freezing drizzle attm. Overnight lows
are forecast to be in the 20s.
Tomorrow:
More of the same continues with the upslope flow. Some partial clearing
is expected as drier air works in. Still, should be cloudy for a good
portion of the day, particularly across the north. Tomorrow will cooler
with upper 30s by Hays to lower 40s near the Oklahoma border.
.LONG TERM...(Sunday night through Saturday)
ISSUED AT 331 PM CST SAT FEB 22 2014
A deep upper level trough will remain across eastern Canada and
the Great Lakes into early March, delivering occasional shots of
cold air from Canada into Kansas. Upper ridging will remain across
western Canada for several days. Meanwhile, mid to high level flow
will undercut the upper level ridge and progress into the
southwestern United States and southern plains. Given the
progressiveness of this southern stream, large amounts of
precipitation are not expected. In the meantime, lee troughing and
south winds will develop Monday in advance of a shortwave trough,
with highs in the 50s and 60s across most of southwest Kansas.
Some light snow may occur Tuesday as this shortwave trough rotates
around the larger, eastern Canadian long wave trough in the wake
of an arctic front. Highs on Tuesday will probably be in the 20s
to lower 30s given the amount of cold air currently poised across
southern Canada and the northern plains. The gfs and especially
the NAM were disregarded for Tuesday`s forecast and the GEM/ECMWF
were favored. The NAM is usually not worth considering that far
out since since it`s a limited domain model. So we believe that
the warmer solution for Tuesday is in error. Aside from Tuesday,
temperatures will be fairly seasonal through the week. However,
another shot of colder air may arrive by Saturday and remain for
several days. A snow event can`t be ruled out around March 3rd as
a shortwave trough in the southern stream approaches and interacts
with cold air in place. But the models have been inconsistent with this
scenario and lots of uncertainty still exists. Early March looks
cold, especially relative to climatology. Eventually, if we keep
the cold pattern, a shortwave trough in the southern stream could
bring winter weather into western Kansas.
&&
.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
ISSUED AT 507 PM CST SAT FEB 22 2014
An easterly upslope flow will continue overnight across western
Kansas as an area of high pressure moves across the northern
plains towards the mid Mississippi valley overnight. In addition
the 18z BUFR soundings indicated that the lower levels of the
atmosphere will moisten overnight as this upslope flow near the
surface increases in depth. Based on the model soundings and the
20z HRRR will introduce increasing low clouds after midnight. At
this time the ceilings are expected to be mainly between 1000 and
1500ft AGL. A brief period of IFR conditions at DDC and GCK not
completely out of the question between 11z and 14z. Reduced
visibilities due to fog at this time does not appear to be an
issue tonight given the mixing potential near the surface from the
18z NAM BUFR sounding.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 25 40 22 53 / 10 10 0 0
GCK 25 40 22 56 / 10 10 0 0
EHA 26 43 24 66 / 0 0 0 10
LBL 27 44 24 58 / 0 0 0 0
HYS 26 37 21 48 / 10 10 10 0
P28 28 42 25 52 / 0 0 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Sugden
LONG TERM...Finch
AVIATION...Burgert
AREA FORECAST DISCUSSION...CORRECTED
NWS BALTIMORE MD/WASHINGTON DC
456 AM EST FRI FEB 21 2014
.SYNOPSIS...
A WARM FRONT IS POSITIONED ACROSS SOUTHERN VIRGINIA WHILE A COLD FRONT
STRETCHES FROM OHIO TO ALABAMA. THE COLD FRONT WILL MOVE THROUGH
THE MID ATLANTIC BY EARLY AFTERNOON. HIGH PRESSURE WILL RETURN
OVER THE WEEKEND. UNSETTLED WEATHER IS POSSIBLE TUESDAY.
&&
.NEAR TERM /TODAY/...
QUITE A CHANGEABLE PD IN THE MID ATLC - CLOSE TO 1.5 FT OF SNOW
ACROSS MUCH OF THE AREA A WK AGO HAS BEEN LARGELY MELTED AWAY. A
CHECK OF SNOW ON THE GRND RECORDS (SOLELY IAD) SHOW IT IS INDEED
HARD TO KEEP SNOWPACK ON GRND VERY LONG - IN 42 YRS OF RECORDS
MORE THAN 1" OF SNOW ON GRND HAS ONLY RMND ON GRND LONGER THAN ONE
WK 25 TIMES. RECORD LENGTH OF TIME WAS AT THE END OF 1969 - 23 DAYS.
PRSNT SFC ANLYS/OBS SHOW A WARM FNT ALONG THE NC/VA BRDR CURVING
UP INTO SERN VA. IN SOME LOCATIONS THERE`S A 15-20 TEMP DIFFERENCE
OVR THE COURSE OF 20 MILES. AND TO OUR W IS A FAST MOVG CD FNT -
THRU 3 AM CRW WAS ISSUING WRNGS ON IT: THEIR OFFICE RCVD A GUST TO
60 MPH AT 220 AM.
THE CD FNT WL BE PUSHING INTO THE APLCHNS ARND 14Z...QUICKLY
REACHING THE BAY ABT 5 HRS LATER. QUSTN THEN BECOMES HOW MUCH OF
THE CD WEDGE ON THE N SIDE OF THE WARM FNT WL BE ERODED AWAY B4
THE CD FNT MOVES IN. THIS IN TURN MAKES FOR AN XTRMLY CHALLENGING
TEMP FCST. USED HRRR 2M TEMP FIELD AS A GUIDE..AS WELL AS PAST
HISTORY ON SYNTOPIC SITUATIONS SUCH AS THIS: SUSPECT THAT THE
COLDER WEDGE WL NOT BE PUSHED OUT W/ THE XCPTN OF LWR SRN
MD...WHERE IT MAY HAPPEN FOR AN HOUR OR TWO B4 THE CD FNT MOVES THRU.
NEXT CONCERN IS SVR/WIND THREATS. THE TIME OF DAY THE FNT IS PASSING
THRU IS NOT OPTIMAL FOR CNVCTV DVLPMNT...AND LTNG ACTVTY HAS BEEN
DIMINISHING AND TRACKING FURTHER S AS THE NGT PROGRESSES. BUT AT
THIS TIME OF YR LTNG IS NOT THE ONLY CONCERN...AS IS WITNESSED BY
THE WRNGS/OBS BEING XPRNCD IN W.V. LOW TOPPED FAST MOVG STORMS CAN
BRING STRONG WINDS TO THE SFC...AND IAD VWP IS SHOWING WINDS INXS
OF 70 KT AT FL 040. WE HV ISSUED A WIND ADVSRY FOR THE HIGHER
ELEVS BECAUSE OF THIS.
TEMP FCST - CONFIDENCE IS NOT AT ITS HIGHEST...BUT MUCH OF THE
AREA SHOULD SEE THE L50S FOR HIGHS...LWR SRN MD MAY END UP ABT TEN
DEGS WRMR B4 THE CD FNT PUSHES THRU.
&&
.SHORT TERM /TONIGHT/...
TNGT IS A LESS CHALLENGING FCST AS HIGH PRES MOVES IN BEHIND THE
FNT. LOWS IN THE 20S W OF THE BLUE RDG...30S ELSEWHERE.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
ZONAL FLOW ALOFT MOVES IN THIS WEEKEND BEHIND TODAY/S COLD FRONTAL
PASSAGE. SATURDAY LOOKS TO BE A MILD DAY WITH ZONAL FLOW
ALOFT...PLENTY OF SUNSHINE AND A SOUTHWEST WIND IN THE LOW LEVELS.
THIS WILL BOOST TEMPERATURES WELL INTO THE 50S AND PERHAPS ABOVE 60
IN SOME AREAS SATURDAY AFTERNOON.
SAT NGT THRU THU/...
WE EXPECT INCREASING CLOUDS SATURDAY NIGHT INTO SUNDAY AS A
SHORTWAVE APPROACHES. AT THE SURFACE...A COLD FRONTAL PASSAGE WILL
OCCUR DURING THE DAY SUNDAY. ANOTHER SHORTWAVE ON THE HEELS OF THE
FRONT MAY BRING A CHANCE OF SNOW SHOWERS SUNDAY NIGHT NEAR THE MASON
DIXON LINE AND OVER THE POTOMAC HIGHLANDS.
CANADIAN HIGH PRESSURE THEN BUILDS IN FOR MONDAY WITH A COLDER AIR
MASS TAKING HOLD OVER THE MID ATLANTIC. THIS COLDER AIR MASS WILL
NOT ONLY STICK AROUND THROUGH MID-WEEK BUT WILL LIKELY BE REINFORCED
THROUGH THIS TIME.
THERE IS STILL THE POTENTIAL FOR SOME WINTRY PRECIPITATION IN THE
TUESDAY TO WEDNESDAY TIME FRAME...BUT UNCERTAINTY REMAINS REGARDING
THE DETAILS INCLUDING TIMING AND STRENGTH. KEPT LOW CHANCE POPS IN
THE FORECAST.
&&
.AVIATION /09Z FRIDAY THROUGH TUESDAY/...
CONDS WL BE DIMINISHING RAPIDLY THIS MRNG AS A FAST MOVG CD FNT
ROLLS THRU THE MID ATLC AREA. IAD VWP IS SHOWING 70 KT AT FL
040...LLWX WL BE XPRNCD BY AIRCRAFT THIS MRNG. HVY RW DURG THE
11-18Z TIME WL CAUSE DIMINISHED CIGS AND VSBYS.
VFR CONDS TNGT.
SATURDAY INTO EARLY NEXT WEEK...NO SIGNIFICANT WX EXPECTED WITH A
WEAK COLD FRONT SUNDAY AND THEN HIGH PRESSURE MONDAY. NEXT STORM
APPROACHES WITH A CHANCE OF RAIN OR SNOW TUESDAY.
&&
.MARINE...
AN SCA IS IN EFFECT FOR ALL WATERS TDA. SMW`S MAY BE NEEDED...
ESPECIALLY IN LWR TIDAL PTMC AND CHES BAY S OF DRUM PT DURG LATE
MRNG/ERLY AFTN.
HIGH PRESSURE BUILDS IN SATURDAY...THEN A COLD FRONT MOVES THROUGH
SUNDAY. SCA IS LIKELY ON MONDAY IN NORTHWEST WINDS BEHIND THE
FRONT.
&&
.HYDROLOGY...
WE`VE LOST UP TO ONE INCH OF SNOW WATER IN THE PAST TWO DAYS AREA
WIDE. SNOW WATER EQUIVALENT VALUES ARE STILL QUITE HIGH IN THE FAR
POTOMAC HIGHLANDS...BUT THE HIGHEST VALUES ARE MAINLY UPSTREAM OF
JENNINGS RANDOLPH AND SAVAGE RIVER LAKES...AND THE OVERALL VALUES
ARE MUCH LESS THAN OBSERVED IN PREVIOUS SNOWMELT FLOOD EVENTS.
THERE WILL BE MORE MELT TODAY. THAT WILL BE ENOUGH TO CAUSE RIVER
RISES AND THESE ARE REFLECTED IN THE CURRENT RIVER FORECASTS.
RIGHT NOW NONE OF THE FORECASTS RISE TO FLOOD STAGE...BUT IF
SNOWMELT OR RAIN AMOUNTS ON TODAY EXCEED THE CURRENT PROJECTIONS...
SOME MINOR FLOODING WILL BE POSSIBLE... PARTICULARLY ON SMALLER
CREEKS AND STREAMS AND OUR USUAL FIRST-TO-FLOOD SPOTS AMONG THE
RIVER FORECAST POINTS.
THE GRADUAL MELT RESUMES OVER THE WEEKEND...WITH FREEZES EACH NIGHT
AND NO PRECIPITATION EXPECTED. COLDER WEATHER ARRIVES EARLY NEXT
WEEK...SIGNIFICANTLY DECREASING OR STOPPING THE MELT FOR AWHILE.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...WIND ADVISORY UNTIL 2 PM EST THIS AFTERNOON FOR MDZ501.
VA...WIND ADVISORY UNTIL 2 PM EST THIS AFTERNOON FOR VAZ025>027-029-
036>039-503-504.
WV...WIND ADVISORY UNTIL 2 PM EST THIS AFTERNOON FOR WVZ050-055-
501>506.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR
ANZ532>534-537-540>543.
SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR ANZ530-
531-535-536-538-539.
&&
$$
PRODUCTS,,,WOODY!/BPP
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
348 AM EST FRI FEB 21 2014
.SYNOPSIS...
A WARM FRONT IS POSITIONED ACROSS SOUTHERN VIRGINIA WHILE A COLD FRONT
STRETCHES FROM OHIO TO ALABAMA. THE COLD FRONT WILL MOVE THROUGH
THE MID ATLANTIC BY EARLY AFTERNOON. HIGH PRESSURE WILL RETURN
OVER THE WEEKEND. UNSETTLED WEATHER IS POSSIBLE TUESDAY.
&&
.NEAR TERM /TODAY/...
QUITE A CHANGEABLE PD IN THE MID ATLC - CLOSE TO 1.5 FT OF SNOW
ACROSS MUCH OF THE AREA A WK AGO HAS BEEN LARGELY MELTED AWAY. A
CHECK OF SNOW ON THE GRND RECORDS (SOLELY IAD) SHOW IT IS INDEED
HARD TO KEEP SNOWPACK ON GRND VERY LONG - IN 42 YRS OF RECORDS
MORE THAN 1" OF SNOW ON GRND HAS ONLY RMND ON GRND LONGER THAN ONE
WK 25 TIMES. RECORD LENGTH OF TIME WAS AT THE END OF 1969 - 23 DAYS.
PRSNT SFC ANLYS/OBS SHOW A WARM FNT ALONG THE NC/VA BRDR. THE FNT
HAS ACTUALLY PUSHED INTO SERN VA - IN SOME LOCATIONS THERE`S A
15-20 TEMP DIFFERENCE OVR THE COURSE OF 20 MILES. AND TO OUR W IS
A FAST MOVG CD FNT - CRW HAS BEEN ISSUING WRNGS ON IT SINCE MDNGT:
THEIR OFFICE RCVD A GUST TO 60 MPH AT 220 AM.
THE CD FNT WL BE PUSHING INTO THE APLCHNS ARND 14Z...QUICKLY
REACHING THE BAY ABT 5 HRS LATER. QUSTN THEN BECOMES HOW MUCH OF
THE CD WEDGE ON THE N SIDE OF THE WARM FNT WL BE ERODED AWAY B4
THE CD FNT MOVES IN. THIS IN TURN MAKES FOR AN XTRMLY CHALLENGING
TEMP FCST. USED HRRR 2M TEMP FIELD AS A GUIDE..AS WELL AS PAST
HISTORY ON SYNTOPIC SITUATIONS SUCH AS THIS: SUSPECT THAT THE
COLDER WEDGE WL NOT BE PUSHED OUT W/ THE XCPTN OF LWR SRN
MD...WHERE IT MAY HAPPEN FOR AN HOUR OR TWO B4 THE CD FNT MOVES THRU.
NEXT CONCERN IS SVR/WIND THREATS. THE TIME OF DAY THE FNT IS PASSING
THRU IS NOT OPTIMAL FOR CNVCTV DVLPMNT...AND LTNG RMNS OVR NC AND
PTS S. BUT AT THIS TIME OF YR LTNG IS NOT THE ONLY CONCERN...AS IS
WITNESSED BY THE WRNGS/OBS BEING XPRNCD IN W.V. LOW TOPPED FAST
MOVG STORMS CAN BRING STRONG WINDS TO THE SFC...AND IAD VWP IS
SHOWING WINDS INXS OF 70 KT AT FL 040. WE HV ISSUED A WIND ADSRVY
FOR THE HIGHER ELEVS BECAUSE OF THIS.
TEMP FCST - CONFIDENCE IS NOT AT ITS HIGHEST...BUT MUCH OF THE
AREA SHOULD SEE THE L50S FOR HIGHS...LWR SRN MD MAY END UP ABT TEN
DEGS WRMR B4 THE CD FNT PUSHES THRU.
&&
.SHORT TERM /TONIGHT/...
TNGT IS A LESS CHALLENGING FCST AS HIGH PRES MOVES IN BEHIND THE
FNT. LOWS IN THE 20S W OF THE BLUE RDG...30S ELSEWHERE.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
ZONAL FLOW ALOFT MOVES IN THIS WEEKEND BEHIND TODAY/S COLD FRONTAL
PASSAGE. SATURDAY LOOKS TO BE A MILD DAY WITH ZONAL FLOW
ALOFT...PLENTY OF SUNSHINE AND A SOUTHWEST WIND IN THE LOW LEVELS.
THIS WILL BOOST TEMPERATURES WELL INTO THE 50S AND PERHAPS ABOVE 60
IN SOME AREAS SATURDAY AFTERNOON.
SAT NGT THRU THU/...
WE EXPECT INCREASING CLOUDS SATURDAY NIGHT INTO SUNDAY AS A
SHORTWAVE APPROACHES. AT THE SURFACE...A COLD FRONTAL PASSAGE WILL
OCCUR DURING THE DAY SUNDAY. ANOTHER SHORTWAVE ON THE HEELS OF THE
FRONT MAY BRING A CHANCE OF SNOW SHOWERS SUNDAY NIGHT NEAR THE MASON
DIXON LINE AND OVER THE POTOMAC HIGHLANDS.
CANADIAN HIGH PRESSURE THEN BUILDS IN FOR MONDAY WITH A COLDER AIR
MASS TAKING HOLD OVER THE MID ATLANTIC. THIS COLDER AIR MASS WILL
NOT ONLY STICK AROUND THROUGH MID-WEEK BUT WILL LIKELY BE REINFORCED
THROUGH THIS TIME.
THERE IS STILL THE POTENTIAL FOR SOME WINTRY PRECIPITATION IN THE
TUESDAY TO WEDNESDAY TIME FRAME...BUT UNCERTAINTY REMAINS REGARDING
THE DETAILS INCLUDING TIMING AND STRENGTH. KEPT LOW CHANCE POPS IN
THE FORECAST.
&&
.AVIATION /09Z FRIDAY THROUGH TUESDAY/...
CONDS WL BE DIMINISHING RAPIDLY THIS MRNG AS A FAST MOVG CD FNT
ROLLS THRU THE MID ATLC AREA. IAD VWP IS SHOWING 70 KT AT FL
040...LLWX WL BE XPRNCD BY AIRCRAFT THIS MRNG. HVY RW DURG THE
11-18Z TIME WL CAUSE DIMINISHED CIGS AND VSBYS.
VFR CONDS TNGT.
SATURDAY INTO EARLY NEXT WEEK...NO SIGNIFICANT WX EXPECTED WITH A
WEAK COLD FRONT SUNDAY AND THEN HIGH PRESSURE MONDAY. NEXT STORM
APPROACHES WITH A CHANCE OF RAIN OR SNOW TUESDAY.
&&
.MARINE...
AN SCA IS IN EFFECT FOR ALL WATERS TDA. SMW`S MAY BE NEEDED...
ESPECIALLY IN LWR TIDAL PTMC AND CHES BAY S OF DRUM PT DURG LATE
MRNG/ERLY AFTN.
HIGH PRESSURE BUILDS IN SATURDAY...THEN A COLD FRONT MOVES THROUGH
SUNDAY. SCA IS LIKELY ON MONDAY IN NORTHWEST WINDS BEHIND THE
FRONT.
&&
.HYDROLOGY...
WE`VE LOST UP TO ONE INCH OF SNOW WATER IN THE PAST TWO DAYS AREA
WIDE. SNOW WATER EQUIVALENT VALUES ARE STILL QUITE HIGH IN THE FAR
POTOMAC HIGHLANDS...BUT THE HIGHEST VALUES ARE MAINLY UPSTREAM OF
JENNINGS RANDOLPH AND SAVAGE RIVER LAKES...AND THE OVERALL VALUES
ARE MUCH LESS THAN OBSERVED IN PREVIOUS SNOWMELT FLOOD EVENTS.
THERE WILL BE MORE MELT TODAY. THAT WILL BE ENOUGH TO CAUSE RIVER
RISES AND THESE ARE REFLECTED IN THE CURRENT RIVER FORECASTS.
RIGHT NOW NONE OF THE FORECASTS RISE TO FLOOD STAGE...BUT IF
SNOWMELT OR RAIN AMOUNTS ON TODAY EXCEED THE CURRENT PROJECTIONS...
SOME MINOR FLOODING WILL BE POSSIBLE... PARTICULARLY ON SMALLER
CREEKS AND STREAMS AND OUR USUAL FIRST-TO-FLOOD SPOTS AMONG THE
RIVER FORECAST POINTS.
THE GRADUAL MELT RESUMES OVER THE WEEKEND...WITH FREEZES EACH NIGHT
AND NO PRECIPITATION EXPECTED. COLDER WEATHER ARRIVES EARLY NEXT
WEEK...SIGNIFICANTLY DECREASING OR STOPPING THE MELT FOR AWHILE.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...WIND ADVISORY UNTIL 2 PM EST THIS AFTERNOON FOR MDZ501.
VA...WIND ADVISORY UNTIL 2 PM EST THIS AFTERNOON FOR VAZ025>027-029-
036>039-503-504.
WV...WIND ADVISORY UNTIL 2 PM EST THIS AFTERNOON FOR WVZ050-055-
501>506.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR
ANZ532>534-537-540>543.
SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR ANZ530-
531-535-536-538-539.
&&
$$
PRODUCTS,,,WOODY!/BPP
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
1204 AM EST FRI FEB 21 2014
.SYNOPSIS...
A WARM FRONT LIFTS NORTH OF THE REGION THIS MORNING. A COLD FRONT
CROSSES THE AREA LATER TODAY. HIGH PRESSURE AND DRIER CONDITIONS
RETURN FOR THE WEEKEND.
&&
.NEAR TERM /OVERNIGHT/...
LATEST MSAS SHOWING WARM FRONT LIFTG NORTH ACROSS THE AREA ATTM.
QUITE A TEMP CONTRAST ACROSS THE AREA AT MIDNIGHT. CRNTLY 41 AT
LKU RANGING TO 66 AT NTU. WILL DO A QUICK UPDATE TO ACCOUNT FOR
THE 10+ DEGREE TEMP / DP TEMP RISE BEHIND WARM FRONT PAST FEW
HOURS. WILL CALL THE MIDNIGHT OBS THE MIN TEMP ACROSS THE NORTH
WITH RISING TMPS OVERNIGHT...OTW STDY 60-65. NAM12 SEEMS TO BEST
DEPICT THE TMP CHANGES.
PVS DSCN:
VRB CLDS TO MCLDY ACRS THE FA. WARM FRONT RMNS SLO TO MOVE N
THROUGH THE RGN THIS EVE...WILL DO SO...W/ LAST PLACES TO LOSE THE
LO LVL WEDGE WNW OF RIC. MDLS DIFFER AS TO LO CIGS OR DEVELOPMENT.
WILL INCLUDE AREAS OF FG OVR PORTIONS OF THE WTRS OVRNGT AS THE
WARM AIR PUSHES NWD OVR THE COLDER BAY/OCN WTRS...OTRW CONTG W/
MNLY MCLDY SKY COVER. LO TEMPS ABT REACHED IN MOST PLACES...ESP
SRN VA/NE NC. A RISE IN TEMPS XPCD IN ALL AREAS AS WARM FRONT
CONTS N.
HAVE CUTBACK POPS TO 20% AFTR 09Z WEST OF I95 FOR SLOWER ARRIVAL
TO PCPN. DRY ELSEWHERE.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY/...
THE APPROACHING COLD FRONT WILL MOVE INTO THE WRN HALF OF THE CWA BY
MID-LATE MORNING AND THEN CROSS THE ERN HALF DURING THE AFTN...
PUSHING OFFSHORE DURING THE EVENING. THE BULK OF RAINFALL WILL
OCCUR RIGHT ALONG AND BEHIND THE FRONT WHICH WILL THEN CONTINUE
INTO FRIDAY EVENING BEFORE TAPERING OFF FROM WEST TO EAST. THERE
ARE SEVERAL PARAMETERS THAT WILL SUPPORT THUNDERSTORM DEVELOPMENT
ON FRIDAY DESPITE THE BEST DYNAMICS LYING WELL TO THE NORTH. THE
AREA WILL BE LOCATED ALONG THE RIGHT ENTRANCE REGION OF THE UPPER
LEVEL JET PLUS THERE IS DECENT MID LEVEL INSTABILITY (850-500 MB)
PRESENT...BOTH OF WHICH SUPPORT ENHANCED LIFT. 0-1 KM WIND SHEAR
PROFILES VEER FROM SOUTH TO SOUTHWEST AND THEN BECOME UNIDIRECTIONAL
FROM THE SOUTHWEST ABOVE 1 KM. THIS TYPE OF SHEAR PROFILE SUPPORTS
THUNDERSTORM LINE SEGMENTS AND ULTIMATELY A THREAT FOR GUSTY
THUNDERSTORM WINDS. AT THE SFC...SOUTH WINDS OF 15-20 MPH WILL
INCREASE IN STRENGTH AND BECOME GUSTY JUST AHEAD OF THE COLD
FRONTAL PASSAGE DURING THE LATE MORNING/EARLY AFTERNOON HOURS.
NON-THUNDERSTORM WIND GUSTS SHOULD AVERAGE AROUND 30-35 MPH.
MEANWHILE...THUNDERSTORM WIND GUSTS SHOULD RANGE FROM 30-50 MPH
WITH LOCALLY HIGHER GUSTS POSSIBLE. PWATS INCREASE TO 1.00-1.50
INCHES DURING THE DAY. THIS WILL CONTRIBUTE TO THE POTENTIAL FOR
MODERATE TO HEAVY RAINFALL AT TIMES...ESPECIALLY UNDER STRONGER
STORM CORES. STORM TOTAL QPF SHOULD AVERAGE 0.50 INCHES WITH
LOCALLY HIGHER AMOUNTS POSSIBLE DUE TO CONVECTION. TEMPERATURES
WILL BE TRICKY AND HIGHLY DEPENDENT ON THE FROPA TIMING. TRENDING
TWD A LATER ARRIVAL OF THE FRONT MEANS THAT TEMPS SHOULD TAKE ON
MORE OF A NORMAL DIURNAL TREND...BUT MAY PEAK BY LATE MORNING FAR
WRN AREAS AND BY EARLY AFTN FOR THE ERN HALF OF THE FA. HIGH TEMPS
RANGE FROM THE LOWER 60S NW/N TO UPPER 60S SE (AROUND 70 COASTAL
NE NC).
PRECIP COMES TO AN END FRIDAY EVENING AS THE FRONT PUSHES WELL
OFFSHORE. DECENT CLEARING AND WINDS BECOMING LIGHT WILL ALLOW TEMPS
TO DROP INTO THE LOW-MID 30S NW TO UPPER 30S SE BY SATURDAY MORNING.
HIGH PRESSURE AND DRIER CONDITIONS WILL PREVAIL SATURDAY INTO
SUNDAY. HIGHS WILL GENERALLY BE IN THE 60S SAT/SUN WITH LOWS SUNDAY
MORNING IN THE MID-UPPER 30S.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
HIGH LATITUDES CONTINUE TO BE DOMINATED BY A DYNAMIC/HIGHLY
AMPLIFIED PATTERN THROUGH THE EXTENDED. QUASI-ZONAL FLOW OVER THE
CONUS TO BEGIN THE EXTENDED WILL AMPLIFY EARLY NEXT WEEK...
CHARACTERIZED BY A MEAN RIDGE IN THE WEST AND DEEPENING TROUGH IN
THE EAST. SHORTWAVE ENERGY IN THE NRN STREAM...ROUNDING THE BASE
OF A STRONG -2 TO -3 STD DEV UPPER LOW...WILL IMPACT THE NE INTO
THE MID- ATLANTIC THROUGH THE EXTENDED. HOWEVER...THESE WAVES ARE
TYPICALLY DIFFICULT TO TIME AND THERE REMAINS LARGE SPREADS IN
ENSEMBLE GUIDANCE AND DETERMINISTIC RUNS. THE FIRST WAVE WILL PUSH
A CLIPPER FRONT THROUGH THE REGION SUN NIGHT-MON MORNING. FRONTAL
PASSAGE ANTICIPATED TO BE DRY AS PROFILES SHOW LIMITED NRN STREAM
MOISTURE AND WLY FLOW. HIGH PRESSURE BUILDS IN BEHIND THE DEPARTING
FRONT MON. SPATIAL AND TIMING DIFFERENCES WITH THE SFC HIGH RESULT
IN A TRICKY TEMP FORECAST MON AS LOW LEVEL THICKNESSES BTWN
GFS/GEFS AND ECMWF ARE NEARLY 30 M. THE RESULT WOULD BE HIGHS IN
THE MID 40S OR MID 50S. PREFERRED AN ENSEMBLE/WPC APPROACH TO
SMOOTH OUT THE DIFFERENCES FOR THE TIME BEING WITH TEMPS SLIGHTLY
BELOW SEASONAL NORMS (HIGHS MID 40S NORTH TO LOW 50S SOUTH). THE
NEXT SHORTWAVE WILL TRAVERSE THE NE STATES TUES AS A WEAK SRN
STREAM WAVE DEVELOPS A LOW ALONG THE STALLED COLD FRONT OVER THE
GULF STATES. MODELS KEEP ANY MEASURABLE PRECIP SOUTH OF THE
REGION...WHICH MATCHES WELL WITH THE DEEPENING TROUGH OVER THE ERN
CONUS. WHILE CONDITIONS WILL REMAIN DRY TUES...DO ANTICIPATE
INCREASING CLOUDS THROUGH THE DAY. MORE POTENT SHORTWAVE DIGGING
OVER THE GREAT LAKES LATE TUES-TUES NIGHT AND INCREASING WINDS
ALOFT WILL DEVELOP A STRONGER WAVE ALONG THE FRONT OFF THE SE
COAST TUES NIGHT. LOW WILL LIFT OFF THE MID-ATLANTIC COAST WEDS
MORNING. HAVE OPTED TO MAINTAIN SLIGHT CHANCE POPS INLAND DUE TO
UNCERTAINTY (WHILE THE TREND MAY BE TO TAKE THEM OUT) BUT HAVE
INCREASED THE COAST TO LOW END CHANCE POPS TUES NIGHT-WEDS
MORNING. TEMPS MAY BE COLD ENOUGH FOR FROZEN PRECIP BUT CAA LOOKS
MARGINAL DUE TO NO STRONG HIGH PRESSURE TO THE NORTHWEST...SO HAVE
OPTED FOR RAIN OR SNOW WORDING AS FAR SOUTH AS CENTRAL VA. HIGH
PRESSURE BUILDS IN FROM THE WEST WED AFTERNOON THROUGH THE END OF
THE EXTENDED PERIOD...RESULTING IN MOSTLY CLEAR SKIES AND DRY/COOL
CONDITIONS.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
SOUTHERLY WINDS INCREASE OVERNIGHT AS A WARM FRONT MOVES NORTH
THROUGH THE MID ATLANTIC STATES. MOST OF THE MODELS HAVE MOISTURE
INCREASE IN THE LOWER PORTION OF THE BOUNDARY LAYER WITH IFR
DEVELOPING NORTHWARD FROM THE GULF STREAM AND THROUGH EASTERN
NORTH CAROLINA WITH A SIGNIFICANT INCREASE OF SURFACE DEW POINTS.
WITH THE WIND...IFR SHOULD BE MAINLY DUE TO CIG RATHER THAN VSBY.
FOLLOWED CLOSE TO THE NAM AND RUC FOR TIMING...GENERALLY AROUND
07Z. SBY ALREADY HAS MVFR CIGS AND RUC HAS A GOOD HANDLE ON THE
SITUATION...WITH IFR PSBL DURING THE FIRST PART OF THE TAF PERIOD.
ONCE THE AREA BECOMES WARM SECTORED EARLY FRIDAY MORNING...
CONDITIONS MAY IMPROVE BUT FOR NOW KEPT IFR GOING UNTIL AROUND 15Z
AS INDICATED BY MOS FCSTS AND MODEL SOUNDINGS...EXCEPT LIFTING EARLIER
SE PORTIONS. GUSTY WINDS CONTINUE FRIDAY...STARTING FROM THE S/SW
AND BACKING TO W/SW AS THE COLD FRONT MOVES THROUGH DURING THE
AFTN. HAVE A FEW HOURS OF SHOWERS IN THE TAFS BEGINNING BETWEEN 15
AND 18Z. BRIEF IFR IS PSBL DURING HEAVIER SHOWERS.
OUTLOOK...MAINLY DRY AND VFR CONDS ARE EXPECTED SATURDAY THROUGH
TUESDAY.
&&
.MARINE...
AS OF 0430Z...WINDS INCREASING OVER THE SOUTHERN END OF THE BAY AS
THE WARM FRONT MOVES THROUGH. SCA CONDITIONS WILL DEVELOP ACROSS
THE WATERS DURING THE EARLY MORNING HOURS. WINDS OF SCA STRENGTH
MAY BE INTERMITTENT DURING THE OVERNIGHT DUE TO THE COLD WATER
TEMPERATURE BUT WILL INCREASE TO A MORE SOLID SCA DURING THE DAY
FRIDAY. THE WINDS SHOULD EASILY TO SCA THRESHOLDS DURING THE DAY
FRIDAY.
FROM PREVIOUS DISCUSSION...
GRADIENT WILL STRENGTHEN OVER THE WATERS IN ADVANCE OF A STRONG
COLD FRONT WITH SLY WINDS REACHING SCA SPEEDS AROUND MIDNIGHT
TONIGHT. WHILE A STRONG LOW LEVEL INVERSION WILL PREVENT THE
STRONGEST WINDS ALOFT FROM REACHING THE WATER...PRESSURE FALLS AND
THE TIGHT GRADIENT WILL PRODUCE WINDS OF 15-25 KT OVER THE BAY AND
20-30 KT OVER THE COASTAL WATERS. STRONG WINDS WILL CONTINUE INTO
FRI BEFORE THE COLD FRONT CROSSES THE WATERS FRIDAY AFTERNOON.
SHOWERS AND THUNDERSTORMS WILL ALSO ACCOMPANY THE FRONT...WHICH
MAY PRODUCE STRONGER WIND GUSTS WITH CONVECTION. AS THE FRONT
CROSSES THE WATERS AND WINDS BACK TO THE NW...ANTICIPATE A QUICK
SURGE POST FRONTAL BEFORE WINDS DIMINISH FRIDAY NIGHT AS HIGH
PRESSURE BUILDS IN FROM THE SOUTHWEST. WAVES MAY BRIEFLY INCREASE
TO 4 FT AROUND MIDDAY FRIDAY ON THE BAY. MEANWHILE...SEAS WILL
BUILD TO 5-6 FT ON THE SOUTHERN COASTAL WATERS...AND 6-8 FT ON THE
NORTHERN COASTAL WATERS. HEADLINES ARE IN EFFECT FOR ALL WATERS
FROM AFTER MIDNIGHT TONIGHT THROUGH 4PM FRIDAY. RIVERS DROP OFF
FIRST BEFORE THE BAY AT 6PM AND THE NRN COASTAL WATERS AT MIDNIGHT
FRI NIGHT. HIGH PRESSURE REMAINS OVER THE WATERS THROUGH THE
WEEKEND BEFORE A CLIPPER FRONT CROSSES THE WATERS SUNDAY NIGHT-
MONDAY MORNING.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 PM EST FRIDAY FOR ANZ635>638.
SMALL CRAFT ADVISORY UNTIL 6 PM EST FRIDAY FOR ANZ630>634.
SMALL CRAFT ADVISORY UNTIL MIDNIGHT EST FRIDAY NIGHT FOR
ANZ650-652-654.
SMALL CRAFT ADVISORY UNTIL 7 PM EST FRIDAY FOR ANZ656-658.
&&
$$
SYNOPSIS...MPR
NEAR TERM...ALB/MPR
SHORT TERM...BMD
LONG TERM...SAM
AVIATION...LSA
MARINE...SAM/LSA
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
1154 PM EST THU FEB 20 2014
.SYNOPSIS...
A WARM FRONT WILL NORTH OF THE REGION OVERNIGHT. A COLD FRONT
CROSSES THE MID ATLANTIC REGION ON FRIDAY. HIGH PRESSURE AND
DRIER CONDITIONS RETURN TO THE REGION DURING THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
VRB CLDS TO MCLDY ACRS THE FA. WARM FRONT RMNS SLO TO MOVE N
THROUGH THE RGN THIS EVE...WILL DO SO...W/ LAST PLACES TO LOSE THE
LO LVL WEDGE WNW OF RIC. MDLS DIFFER AS TO LO CIGS OR DEVELOPMENT.
WILL INCLUDE AREAS OF FG OVR PORTIONS OF THE WTRS OVRNGT AS THE
WARM AIR PUSHES NWD OVR THE COLDER BAY/OCN WTRS...OTRW CONTG W/
MNLY MCLDY SKY COVER. LO TEMPS ABT REACHED IN MOST PLACES...ESP
SRN VA/NE NC. A RISE IN TEMPS XPCD IN ALL AREAS AS WARM FRONT
CONTS N.
HAVE CUTBACK POPS TO 20-30% (LATE TNGT) ALG/W OF I 95 FOR SLOWER
ARRIVAL TO PCPN. ELSW...POPS AOB 10%.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY/...
THE APPROACHING COLD FRONT WILL MOVE INTO THE WRN HALF OF THE CWA BY
MID-LATE MORNING AND THEN CROSS THE ERN HALF DURING THE AFTN...
PUSHING OFFSHORE DURING THE EVENING. THE BULK OF RAINFALL WILL
OCCUR RIGHT ALONG AND BEHIND THE FRONT WHICH WILL THEN CONTINUE
INTO FRIDAY EVENING BEFORE TAPERING OFF FROM WEST TO EAST. THERE
ARE SEVERAL PARAMETERS THAT WILL SUPPORT THUNDERSTORM DEVELOPMENT
ON FRIDAY DESPITE THE BEST DYNAMICS LYING WELL TO THE NORTH. THE
AREA WILL BE LOCATED ALONG THE RIGHT ENTRANCE REGION OF THE UPPER
LEVEL JET PLUS THERE IS DECENT MID LEVEL INSTABILITY (850-500 MB)
PRESENT...BOTH OF WHICH SUPPORT ENHANCED LIFT. 0-1 KM WIND SHEAR
PROFILES VEER FROM SOUTH TO SOUTHWEST AND THEN BECOME UNIDIRECTIONAL
FROM THE SOUTHWEST ABOVE 1 KM. THIS TYPE OF SHEAR PROFILE SUPPORTS
THUNDERSTORM LINE SEGMENTS AND ULTIMATELY A THREAT FOR GUSTY
THUNDERSTORM WINDS. AT THE SFC...SOUTH WINDS OF 15-20 MPH WILL
INCREASE IN STRENGTH AND BECOME GUSTY JUST AHEAD OF THE COLD
FRONTAL PASSAGE DURING THE LATE MORNING/EARLY AFTERNOON HOURS.
NON-THUNDERSTORM WIND GUSTS SHOULD AVERAGE AROUND 30-35 MPH.
MEANWHILE...THUNDERSTORM WIND GUSTS SHOULD RANGE FROM 30-50 MPH
WITH LOCALLY HIGHER GUSTS POSSIBLE. PWATS INCREASE TO 1.00-1.50
INCHES DURING THE DAY. THIS WILL CONTRIBUTE TO THE POTENTIAL FOR
MODERATE TO HEAVY RAINFALL AT TIMES...ESPECIALLY UNDER STRONGER
STORM CORES. STORM TOTAL QPF SHOULD AVERAGE 0.50 INCHES WITH
LOCALLY HIGHER AMOUNTS POSSIBLE DUE TO CONVECTION. TEMPERATURES
WILL BE TRICKY AND HIGHLY DEPENDENT ON THE FROPA TIMING. TRENDING
TWD A LATER ARRIVAL OF THE FRONT MEANS THAT TEMPS SHOULD TAKE ON
MORE OF A NORMAL DIURNAL TREND...BUT MAY PEAK BY LATE MORNING FAR
WRN AREAS AND BY EARLY AFTN FOR THE ERN HALF OF THE FA. HIGH TEMPS
RANGE FROM THE LOWER 60S NW/N TO UPPER 60S SE (AROUND 70 COASTAL
NE NC).
PRECIP COMES TO AN END FRIDAY EVENING AS THE FRONT PUSHES WELL
OFFSHORE. DECENT CLEARING AND WINDS BECOMING LIGHT WILL ALLOW TEMPS
TO DROP INTO THE LOW-MID 30S NW TO UPPER 30S SE BY SATURDAY MORNING.
HIGH PRESSURE AND DRIER CONDITIONS WILL PREVAIL SATURDAY INTO
SUNDAY. HIGHS WILL GENERALLY BE IN THE 60S SAT/SUN WITH LOWS SUNDAY
MORNING IN THE MID-UPPER 30S.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
HIGH LATITUDES CONTINUE TO BE DOMINATED BY A DYNAMIC/HIGHLY
AMPLIFIED PATTERN THROUGH THE EXTENDED. QUASI-ZONAL FLOW OVER THE
CONUS TO BEGIN THE EXTENDED WILL AMPLIFY EARLY NEXT WEEK...
CHARACTERIZED BY A MEAN RIDGE IN THE WEST AND DEEPENING TROUGH IN
THE EAST. SHORTWAVE ENERGY IN THE NRN STREAM...ROUNDING THE BASE
OF A STRONG -2 TO -3 STD DEV UPPER LOW...WILL IMPACT THE NE INTO
THE MID- ATLANTIC THROUGH THE EXTENDED. HOWEVER...THESE WAVES ARE
TYPICALLY DIFFICULT TO TIME AND THERE REMAINS LARGE SPREADS IN
ENSEMBLE GUIDANCE AND DETERMINISTIC RUNS. THE FIRST WAVE WILL PUSH
A CLIPPER FRONT THROUGH THE REGION SUN NIGHT-MON MORNING. FRONTAL
PASSAGE ANTICIPATED TO BE DRY AS PROFILES SHOW LIMITED NRN STREAM
MOISTURE AND WLY FLOW. HIGH PRESSURE BUILDS IN BEHIND THE DEPARTING
FRONT MON. SPATIAL AND TIMING DIFFERENCES WITH THE SFC HIGH RESULT
IN A TRICKY TEMP FORECAST MON AS LOW LEVEL THICKNESSES BTWN
GFS/GEFS AND ECMWF ARE NEARLY 30 M. THE RESULT WOULD BE HIGHS IN
THE MID 40S OR MID 50S. PREFERRED AN ENSEMBLE/WPC APPROACH TO
SMOOTH OUT THE DIFFERENCES FOR THE TIME BEING WITH TEMPS SLIGHTLY
BELOW SEASONAL NORMS (HIGHS MID 40S NORTH TO LOW 50S SOUTH). THE
NEXT SHORTWAVE WILL TRAVERSE THE NE STATES TUES AS A WEAK SRN
STREAM WAVE DEVELOPS A LOW ALONG THE STALLED COLD FRONT OVER THE
GULF STATES. MODELS KEEP ANY MEASURABLE PRECIP SOUTH OF THE
REGION...WHICH MATCHES WELL WITH THE DEEPENING TROUGH OVER THE ERN
CONUS. WHILE CONDITIONS WILL REMAIN DRY TUES...DO ANTICIPATE
INCREASING CLOUDS THROUGH THE DAY. MORE POTENT SHORTWAVE DIGGING
OVER THE GREAT LAKES LATE TUES-TUES NIGHT AND INCREASING WINDS
ALOFT WILL DEVELOP A STRONGER WAVE ALONG THE FRONT OFF THE SE
COAST TUES NIGHT. LOW WILL LIFT OFF THE MID-ATLANTIC COAST WEDS
MORNING. HAVE OPTED TO MAINTAIN SLIGHT CHANCE POPS INLAND DUE TO
UNCERTAINTY (WHILE THE TREND MAY BE TO TAKE THEM OUT) BUT HAVE
INCREASED THE COAST TO LOW END CHANCE POPS TUES NIGHT-WEDS
MORNING. TEMPS MAY BE COLD ENOUGH FOR FROZEN PRECIP BUT CAA LOOKS
MARGINAL DUE TO NO STRONG HIGH PRESSURE TO THE NORTHWEST...SO HAVE
OPTED FOR RAIN OR SNOW WORDING AS FAR SOUTH AS CENTRAL VA. HIGH
PRESSURE BUILDS IN FROM THE WEST WED AFTERNOON THROUGH THE END OF
THE EXTENDED PERIOD...RESULTING IN MOSTLY CLEAR SKIES AND DRY/COOL
CONDITIONS.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
SOUTHERLY WINDS INCREASE OVERNIGHT AS A WARM FRONT MOVES NORTH
THROUGH THE MID ATLANTIC STATES. MOST OF THE MODELS HAVE MOISTURE
INCREASE IN THE LOWER PORTION OF THE BOUNDARY LAYER WITH IFR
DEVELOPING NORTHWARD FROM THE GULF STREAM AND THROUGH EASTERN
NORTH CAROLINA WITH A SIGNIFICANT INCREASE OF SURFACE DEW POINTS.
WITH THE WIND...IFR SHOULD BE MAINLY DUE TO CIG RATHER THAN VSBY.
FOLLOWED CLOSE TO THE NAM AND RUC FOR TIMING...GENERALLY AROUND
07Z. SBY ALREADY HAS MVFR CIGS AND RUC HAS A GOOD HANDLE ON THE
SITUATION...WITH IFR PSBL DURING THE FIRST PART OF THE TAF PERIOD.
ONCE THE AREA BECOMES WARM SECTORED EARLY FRIDAY MORNING...
CONDITIONS MAY IMPROVE BUT FOR NOW KEPT IFR GOING UNTIL AROUND 15Z
AS INDICATED BY MOS FCSTS AND MODEL SOUNDINGS...EXCEPT LIFTING EARLIER
SE PORTIONS. GUSTY WINDS CONTINUE FRIDAY...STARTING FROM THE S/SW
AND BACKING TO W/SW AS THE COLD FRONT MOVES THROUGH DURING THE
AFTN. HAVE A FEW HOURS OF SHOWERS IN THE TAFS BEGINNING BETWEEN 15
AND 18Z. BRIEF IFR IS PSBL DURING HEAVIER SHOWERS.
OUTLOOK...MAINLY DRY AND VFR CONDS ARE EXPECTED SATURDAY THROUGH
TUESDAY.
&&
.MARINE...
AS OF 0430Z...WINDS INCREASING OVER THE SOUTHERN END OF THE BAY AS
THE WARM FRONT MOVES THROUGH. SCA CONDITIONS WILL DEVELOP ACROSS
THE WATERS DURING THE EARLY MORNING HOURS. WINDS OF SCA STRENGTH
MAY BE INTERMITTENT DURING THE OVERNIGHT DUE TO THE COLD WATER
TEMPERATURE BUT WILL INCREASE TO A MORE SOLID SCA DURING THE DAY
FRIDAY. THE WINDS SHOULD EASILY TO SCA THRESHOLDS DURING THE DAY
FRIDAY.
FROM PREVIOUS DISCUSSION...
GRADIENT WILL STRENGTHEN OVER THE WATERS IN ADVANCE OF A STRONG
COLD FRONT WITH SLY WINDS REACHING SCA SPEEDS AROUND MIDNIGHT
TONIGHT. WHILE A STRONG LOW LEVEL INVERSION WILL PREVENT THE
STRONGEST WINDS ALOFT FROM REACHING THE WATER...PRESSURE FALLS AND
THE TIGHT GRADIENT WILL PRODUCE WINDS OF 15-25 KT OVER THE BAY AND
20-30 KT OVER THE COASTAL WATERS. STRONG WINDS WILL CONTINUE INTO
FRI BEFORE THE COLD FRONT CROSSES THE WATERS FRIDAY AFTERNOON.
SHOWERS AND THUNDERSTORMS WILL ALSO ACCOMPANY THE FRONT...WHICH
MAY PRODUCE STRONGER WIND GUSTS WITH CONVECTION. AS THE FRONT
CROSSES THE WATERS AND WINDS BACK TO THE NW...ANTICIPATE A QUICK
SURGE POST FRONTAL BEFORE WINDS DIMINISH FRIDAY NIGHT AS HIGH
PRESSURE BUILDS IN FROM THE SOUTHWEST. WAVES MAY BRIEFLY INCREASE
TO 4 FT AROUND MIDDAY FRIDAY ON THE BAY. MEANWHILE...SEAS WILL
BUILD TO 5-6 FT ON THE SOUTHERN COASTAL WATERS...AND 6-8 FT ON THE
NORTHERN COASTAL WATERS. HEADLINES ARE IN EFFECT FOR ALL WATERS
FROM AFTER MIDNIGHT TONIGHT THROUGH 4PM FRIDAY. RIVERS DROP OFF
FIRST BEFORE THE BAY AT 6PM AND THE NRN COASTAL WATERS AT MIDNIGHT
FRI NIGHT. HIGH PRESSURE REMAINS OVER THE WATERS THROUGH THE
WEEKEND BEFORE A CLIPPER FRONT CROSSES THE WATERS SUNDAY NIGHT-
MONDAY MORNING.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 PM EST FRIDAY FOR ANZ635>638.
SMALL CRAFT ADVISORY UNTIL 6 PM EST FRIDAY FOR ANZ630>634.
SMALL CRAFT ADVISORY UNTIL MIDNIGHT EST FRIDAY NIGHT FOR
ANZ650-652-654.
SMALL CRAFT ADVISORY UNTIL 7 PM EST FRIDAY FOR ANZ656-658.
&&
$$
SYNOPSIS...ALB/BMD
NEAR TERM...ALB/BMD
SHORT TERM...BMD
LONG TERM...SAM
AVIATION...LSA
MARINE...SAM/LSA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
627 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 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 627 PM EST SAT FEB 22 2014
WITH WEAKENING LOW PRES REMAINING IN THE VCNTY OF FAR NRN
ONTARIO/JAMES BAY AND HIGH PRES CONTINUING TO RIDGE SE FROM THE SRN
CANADIAN ROCKIES TO THE MID MISSISSIPPI VALLEY...BLUSTERY WESTERLY
WINDS WILL CONTINUE THRU THIS FCST PERIOD AT KIWD/KCMX/KSAW...BUT
ESPECIALLY AT THE MORE EXPOSED KCMX SITE. WITH WINDS GUSTING OVER
30KT AT KCMX THRU THIS FCST PERIOD...BLSN WILL LIKELY KEEP
PREVAILING VIS IN THE LIFR CATEGORY. EXPECT SOME FLUCTUATION WITH
VIS IMPROVING TO IFR FOR BRIEF PERIODS. WITH THE WESTERLY WINDS AND
SOME GAPS IN THE ICE OVER WESTERN LAKE SUPERIOR...THERE WILL BE OCNL
-SHSN AT KCMX...WHICH WILL ASSIST THE LOWER VISIBILITIES.
DISTURBANCE MAY INCREASE -SHSN COVERAGE SUN AFTN...AND THIS MAY
RESULT IN VIS PERHAPS FALLING BLO 1/2SM AT TIMES.
FOR KIWD/KSAW...VFR CONDITIONS SHOULD PREVAIL TONIGHT INTO SUN
MORNING AS WESTERLY WINDS WON`T BE FAVORABLE FOR LAKE EFFECT
CLOUDS/-SHSN. DEEPER MOISTURE/DISTURBANCE ROTATING INTO THE AREA
DURING THE DAY SUNDAY COULD PRODUCE A MORE SOLID MVFR CLOUD DECK AS
WELL AS SOME -SHSN/FLURRIES.
&&
.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...ROLFSON
MARINE...SRF
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
910 AM MST FRI FEB 21 2014
.UPDATE...
CURRENT FORECAST LOOKS TO BE IN GOOD SHAPE BUT HAVE MADE A FEW
ADJUSTMENTS WITH THIS MORNINGS UPDATE. RADAR CURRENTLY SHOWING
NUMEROUS SNOW SHOWERS DEVELOPING ALONG THE BEARTOOTH FOOTHILLS AND
PRYOR MOUNTAINS WITH SOME NARROW NORTHWEST TO SOUTHEAST SNOW BANDS
FROM AROUND BILLINGS WESTWARD TO THE FOOTHILLS. HAVE RAISED POPS
TO LIKELY FOR THE ENTIRE DAY AS HRRR MODELS SHOWING AREAS OF
SNOWBANDS THROUGHOUT THE DAY ACROSS OUR CENTRAL AND WESTERN
LOCATIONS. EXPECT SCATTERED SNOW SHOWERS EAST OF BILLINGS WITH
MORE NUMEROUS SNOW SHOWERS FROM BILLINGS WESTWARD. ACCUMULATIONS
ARE EXPECTED TO BE GENERALLY LESS THAN AN INCH BUT AREAS THAT ARE
UNDER ANY TRAINING SNOW BANDS MAY PICK UP A QUICK INCH OR TWO.
WILL BE MONITORING THESE SNOW BANDS THROUGHOUT THE DAY AS LATER
UPDATES MAY BE NECESSARY ALONG WITH POSSIBLE ADVISORIES. HOOLEY
&&
.SHORT TERM...VALID FOR TDY AND SAT...
NORTHWEST FLOW ALOFT WILL CONTINUE THROUGH SATURDAY...WITH A
SERIES OF SHORTWAVES MOVING SOUTHEASTWARD THROUGH THE REGION.
SATELLITE SHOWS ONE SHORTWAVE THAT IS GENERATING SOME SNOW
SHOWERS...MOVING THROUGH EASTERN MONTANA...WHILE A MORE POTENT
SHORTWAVE IS ABOUT TO ENTER NORTHWEST MONTANA. AS THAT SHORTWAVE
MOVES THROUGH THE CWA TODAY INTO TONIGHT...IT WILL WORK WITH
STRONG LOW TO MID LEVEL INSTABILITY AND ATTENDANT PACIFIC MOISTURE
TO GENERATE MORE SNOW SHOWERS. THE SYSTEM IS NOT TREMENDOUSLY
ORGANIZED...SO A WIDESPREAD SNOW EVENT DOES NOT APPEAR LIKELY.
WITH THE INSTABILITY AND OROGRAPHIC ENHANCEMENT...THOUGH...WE WILL
SEE SOME PRECIP BANDS FORM...SO IT WOULD NOT SURPRISE ME TO SEE
SOME LOCALIZED REPORTS OF A COUPLE OF INCHES OF SNOW WHERE THESE
BANDS DO SET UP...PARTICULARLY OVER AND DOWNSTREAM OF THE
CRAZIES...LITTLE BELTS...BIG SNOWIES AND BEARTOOTH MOUNTAINS. SOME
UPSLOPE FLOW MAY ALSO ENHANCE THE SNOWFALL POTENTIAL IN THE
BEARTOOTH FOOTHILLS NEAR RED LODGE AND NYE. HIGH TEMPERATURES
TODAY ARE EXPECTED TO REACH THE UPPER 20S TO UPPER 30S. THE LOWER
ATMOSPHERE SHOULD BE WELL MIXED TODAY...ESPECIALLY NEAR SHOWER
ACTIVITY...SO IT WILL BE FAIRLY WINDY.
A MODIFIED ARCTIC AIRMASS WILL MOVE INTO THE REGION TONIGHT INTO
SATURDAY BEHIND THE SHORTWAVE. THIS WILL INCREASE FRONTOGENESIS
AND UPSLOPE FLOW ACROSS THE WESTERN HALF OF THE REGION AT THE SAME
TIME MORE SHORTWAVE ENERGY AND JET ENERGY INFLUENCE THE REGION.
IT WILL NOT BE QUITE AS UNSTABLE IN THE LOW TO MID LEVELS...BUT
THE AFOREMENTIONED FORCING MECHANISMS WILL WORK WITH OROGRAPHIC
ENHANCEMENT IN NW FLOW ALOFT TO CONTINUE TO PRODUCE SNOW IN THE
HIGHER TERRAIN AS WELL AS SOME SNOWBANDS. AGAIN...SOME
ACCUMULATING SNOW IS LIKELY ACROSS THE WESTERN HALF OF THE
REGION...WITH LOCAL ENHANCEMENT IN THE MOUNTAINS AND WITHIN ANY
BAND THAT SETS UP. TEMPERATURES WILL BE QUITE A BIT COLDER
SATURDAY AS HIGHS ARE ONLY EXPECTED TO REACH THE TEENS TO LOW 20S.
STC
.LONG TERM...VALID FOR SUN...MON...TUE...WED...THU...
GREAT AGREEMENT ON ALL MODELS FOR AN UNSEASONABLY COLD STRETCH OF
WEATHER WITH A GREAT CHANCE AT A PROLONGED PERIOD OF ACCUMULATING
SNOW SUNDAY THROUGH MONDAY. STRONG SHORTWAVE TROUGH DROPS OUT OF
CANADA AND SLIDES INTO THE NORTHERN PLAINS SUNDAY WHILE A FLAT
UPPER RIDGE MOVES TOWARD THE GREAT BASIN. THIS PROCESS WILL ALLOW
COLD AIR TO DROP INTO THE FORECAST AREA WITH -20C ADVERTISED AT
850MB. THE FLAT RIDGE TO THE WEST WILL ALLOW PACIFIC MOISTURE TO
STREAM OVER THE COLD AIR AND PRODUCE OVER RUNNING SNOWFALL.
THE 285K SURFACE ADVERTISES THE STRONGEST INSENTROPIC ASCENT ON
SUNDAY NIGHT INTO EARLY MONDAY FOR MOST OF THE AREA. THE
ISENTROPIC LIFT WILL GET GOING SATURDAY NIGHT OVER THE WEST AND
THEN KICK INTO SOUTH CENTRAL MONTANA SUNDAY MORNING AND THEN CRANK
UP LATE SUNDAY AFTERNOON AND SUNDAY NIGHT. HAVE RAISED POPS MOST
LOCATIONS AND STARTED SNOW A LITTLE EARLIER. SNOW WILL CONTINUE
THROUGH THE DAY MONDAY AND VERY SLOWLY TAPER OFF OVER WESTERN AND
CENTRAL ZONES MONDAY NIGHT. RAISED POPS MONDAY NIGHT AS MODEL RUNS
CONTINUE TO DELAY DRYING FROM THE NORTH. WILL EASILY SEE 4 TO 8
INCHES OF SNOW OVER THE TWO DAY PERIOD. TEMPERATURES WILL BE COLD
FOR THIS TIME OF YEAR WITH HIGHS IN THE SINGLE DIGITS TO LOWER
TEENS SUNDAY AND MONDAY. THE COLDEST NIGHT WILL LIKELY BE MONDAY
NIGHT WITH READINGS FALLING BELOW ZERO.
A REINFORCING SHOT OF COLD AIR WILL PLOW THROUGH THE AREA ON
TUESDAY BUT WILL BE LIMITED WITH MOISTURE. THIS WILL SERVE TO KEEP
THINGS UNSEASONABLY COLD AROUND HERE. SUBTLE WARMING SHOULD TAKE
PLACE WEDNESDAY AND THURSDAY IN LOW LEVEL DOWNSLOPE. MODELS WERE
POINTING TO ANOTHER SHOT OF COLD AIR TO PUSH IN FRIDAY AND
SATURDAY. TWH
&&
.AVIATION...
SCATTERED SNOW SHOWERS CAN BE EXPECTED TODAY...ALONG WITH 20-35KT
NORTHWEST WIND GUSTS. THE HEAVIER SNOW SHOWERS WILL DROP
CONDITIONS TO IFR LOCALLY. MOUNTAINS WILL BE FREQUENTLY OBSCURED.
VFR WILL PREVAIL OUTSIDE OF THE SHOWER ACTIVITY. TWH
&&
.PRELIMINARY POINT TEMP/POPS...
TDY SAT SUN MON TUE WED THU
-------------------------------------------------------
BIL 037 014/022 006/015 001/010 902/017 009/023 008/022
6/J 55/S 48/S 97/S 41/B 00/U 12/S
LVM 032 007/020 901/016 002/016 000/023 012/032 011/026
6/J 64/S 48/S 97/S 52/S 01/B 13/S
HDN 037 015/024 009/018 003/011 904/018 004/025 004/023
6/J 54/S 38/S 97/S 31/B 00/U 12/S
MLS 034 011/020 001/013 901/006 000/013 001/018 904/013
4/J 32/S 13/S 74/S 10/U 00/U 12/S
4BQ 035 014/023 008/018 003/010 902/017 002/023 002/020
4/J 33/S 14/S 87/S 31/B 00/U 12/S
BHK 029 006/017 001/010 907/003 905/011 904/017 910/012
6/J 32/S 12/S 63/S 10/U 00/U 01/B
SHR 034 013/019 003/020 004/014 902/020 005/028 005/024
5/J 45/S 46/S 87/S 51/B 01/U 12/S
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS HASTINGS NE
940 PM CST SAT FEB 22 2014
.UPDATE...
ISSUED AT 939 PM CST SAT FEB 22 2014
PER COORDINATION AND WHERE CURRENT SNOW BAND IS SETTING UP...HAVE
EXPANDED WINTER WEATHER ADVISORY TO INCLUDE FURNAS AND HARLAN COUNTIES.
UPDATE ISSUED AT 859 PM CST SAT FEB 22 2014
COMPLICATED FORECAST AS WE HEAD INTO TONIGHT AS TO WHERE SNOW
BANDS WILL SET UP. HAVE BEEN MONITORING SNOW BAND ACROSS WESTERN
NEB WHICH HAS MIGRATED EASTWARD EARLY THIS EVENING. DRIER AIR TO
THE EAST HAS BEEN SLOW TO OVERCOME BUT A SNOW BAND HAS MANAGED TO
MOVE IN AND IS ORIENTED W/E GENERALLY FM KLBF TO KLXN TO KHDE AND
POINTS JUST TO THE SOUTH. THE SNOW IS ALIGNED FAIRLY WELL WITH THE MID
LEVEL FRONTOGENESIS WHICH IS PRIMARILY PROGGED ALONG OUR WESTERN
CWA THROUGH THE FIRST PART OF THE NIGHT. HAVE EXPANDED OUR CURRENT
WINTER WX ADVISORY TO INCLUDE PHELPS AND KEARNEY COUNTIES WHERE
SNOW HAS COMMENCED AND A LONGER DURATION OF SNOW IS EXPECTED. AS
WE HEAD INTO TONIGHT WE SEE AN INCREASE IN ISENTROPIC LIFT AS
INDICATED ON THE 290K SURFACE AND THE LIFT PERSISTS FOR SEVERAL
HOURS...INTO SUNDAY MORNING. THE UPPER JET STREAK NOSES ACROSS
WESTERN NEB SUNDAY MORNING WITH LIFT CONTINUING SUNDAY MORNING IN
LFQ OF JET. ONE OF THE MORE NOTABLE CHANGES IN THE LATEST MODEL
RUNS THAT SNOW IS EXPECTED TO PERSIST LONGER SUNDAY MORNING WITH
ADDITIONAL LIGHT ACCUMULATIONS POSSIBLE. SNOW AMOUNTS WILL BE
DEPENDENT UPON SNOW BANDS WITH SEVERAL INCHES...AND LOCALLY HEAVY
SNOWFALL POSSIBLE WITHIN THE BANDS.
&&
.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 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 521 PM CST SAT FEB 22 2014
THE MAIN FORECAST ISSUE DURING THE TAF PERIOD IS THE DEVELOPMENT
OF A FRONTOGENETIC BAND OF SNOWFALL OVERNIGHT AND INTO SUNDAY
MORNING. SNOW HAS ALREADY DEVELOPED ACROSS WESTERN NEBRASKA AND
THE SNOW SHOULD REACH KGRI AROUND 06Z WITH SNOW CONTINUING
THROUGH THE NIGHT. SNOW ACCUMULATION FOR KGRI IS EXPECTED TO RANGE
FROM 1 TO 3 INCHES. AS THE SNOW DEVELOPS/FALLS...CONDITIONS WILL DROP
TO IFR OR POTENTIALLY LIFR. AS THE SNOW ENDS ON SUNDAY...VSBYS AND
CIGS WILL IMPROVE BUT KEPT AFTN CIGS AT MVFR.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...WINTER WEATHER ADVISORY UNTIL NOON CST SUNDAY FOR NEZ060-061-
072>074-082-083.
KS...NONE.
&&
$$
UPDATE...FAY
SHORT TERM...HALBLAUB
LONG TERM...WESELY
AVIATION...FAY
AREA FORECAST DISCUSSION
NWS HASTINGS NE
920 PM CST SAT FEB 22 2014
.UPDATE...
ISSUED AT 859 PM CST SAT FEB 22 2014
COMPLICATED FORECAST AS WE HEAD INTO TONIGHT AS TO WHERE SNOW
BANDS WILL SET UP. HAVE BEEN MONITORING SNOW BAND ACROSS WESTERN
NEB WHICH HAS MIGRATED EASTWARD EARLY THIS EVENING. DRIER AIR TO
THE EAST HAS BEEN SLOW TO OVERCOME BUT A SNOW BAND HAS MANAGED TO
MOVE IN AND IS ORIENTED W/E GENERALLY FM KLBF TO KLXN TO KHDE AND
POINTS JUST TO THE SOUTH. THE SNOW IS ALIGNED FAIRLY WELL WITH THE MID
LEVEL FRONTOGENESIS WHICH IS PRIMARILY PROGGED ALONG OUR WESTERN
CWA THROUGH THE FIRST PART OF THE NIGHT. HAVE EXPANDED OUR CURRENT
WINTER WX ADVISORY TO INCLUDE PHELPS AND KEARNEY COUNTIES WHERE
SNOW HAS COMMENCED AND A LONGER DURATION OF SNOW IS EXPECTED. AS
WE HEAD INTO TONIGHT WE SEE AN INCREASE IN ISENTROPIC LIFT AS
INDICATED ON THE 290K SURFACE AND THE LIFT PERSISTS FOR SEVERAL
HOURS...INTO SUNDAY MORNING. THE UPPER JET STREAK NOSES ACROSS
WESTERN NEB SUNDAY MORNING WITH LIFT CONTINUING SUNDAY MORNING IN
LFQ OF JET. ONE OF THE MORE NOTABLE CHANGES IN THE LATEST MODEL
RUNS THAT SNOW IS EXPECTED TO PERSIST LONGER SUNDAY MORNING WITH
ADDITIONAL LIGHT ACCUMULATIONS POSSIBLE. SNOW AMOUNTS WILL BE
DEPENDENT UPON SNOW BANDS WITH SEVERAL INCHES...AND LOCALLY HEAVY
SNOWFALL POSSIBLE WITHIN THE BANDS.
&&
.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 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 521 PM CST SAT FEB 22 2014
THE MAIN FORECAST ISSUE DURING THE TAF PERIOD IS THE DEVELOPMENT
OF A FRONTOGENETIC BAND OF SNOWFALL OVERNIGHT AND INTO SUNDAY
MORNING. SNOW HAS ALREADY DEVELOPED ACROSS WESTERN NEBRASKA AND
THE SNOW SHOULD REACH KGRI AROUND 06Z WITH SNOW CONTINUING
THROUGH THE NIGHT. SNOW ACCUMULATION FOR KGRI IS EXPECTED TO RANGE
FROM 1 TO 3 INCHES. AS THE SNOW DEVELOPS/FALLS...CONDITIONS WILL DROP
TO IFR OR POTENTIALLY LIFR. AS THE SNOW ENDS ON SUNDAY...VSBYS AND
CIGS WILL IMPROVE BUT KEPT AFTN CIGS AT MVFR.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...WINTER WEATHER ADVISORY UNTIL NOON CST SUNDAY FOR NEZ060-061-
072>074.
KS...NONE.
&&
$$
UPDATE...FAY
SHORT TERM...HALBLAUB
LONG TERM...WESELY
AVIATION...FAY
AREA FORECAST DISCUSSION
NWS HASTINGS NE
533 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 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 521 PM CST SAT FEB 22 2014
THE MAIN FORECAST ISSUE DURING THE TAF PERIOD IS THE DEVELOPMENT
OF A FRONTOGENETIC BAND OF SNOWFALL OVERNIGHT AND INTO SUNDAY
MORNING. SNOW HAS ALREADY DEVELOPED ACROSS WESTERN NEBRASKA AND
THE SNOW SHOULD REACH KGRI AROUND 06Z WITH SNOW CONTINUING
THROUGH THE NIGHT. SNOW ACCUMULATION FOR KGRI IS EXPECTED TO RANGE
FROM 1 TO 3 INCHES. AS THE SNOW DEVELOPS/FALLS...CONDITIONS WILL DROP
TO IFR OR POTENTIALLY LIFR. AS THE SNOW ENDS ON SUNDAY...VSBYS AND
CIGS WILL IMPROVE BUT KEPT AFTN CIGS AT MVFR.
&&
.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...FAY
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
300 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...(18Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1230 PM CST FRI FEB 21 2014
VFR CONDITIONS THROUGH THE PERIOD. THERE WILL BE AN INCREASE IN
MID CLOUDS THIS AFTERNOON WITH SOME BKN CIGS FL050-060 AND
FL100-120 AND COULD BE SOME FLURRIES OR SPRINKLES. DUE TO ISOLATED
NATURE OF PRECIPITATION WILL NOT MENTION IN TAFS.SURFACE WINDS
WILL BECOME NORTHWEST AND VARY FROM 10 TO 18KTS SUSTAINED WITH
SOME HIGHER GUSTS. AFTER 00Z...THE WINDS WILL SETTLE DOWN TO LESS
THAN 10KTS.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...FOBERT
LONG TERM...DEWALD
AVIATION...ZAPOTOCNY
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
835 PM EST SAT FEB 22 2014
.SYNOPSIS...
AN UPPER LEVEL DISTURBANCE WILL BRING THE CHANCE FOR SNOW SHOWERS
LATE TONIGHT...AND RAIN OR SNOW SHOWERS ON SUNDAY. COLDER AIR
WILL RETURN FOR THE BEGINNING OF THE WORK WEEK WITH LAKE EFFECT
SNOWS OVER CENTRAL NEW YORK.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
8 PM UPDATE... THE CURRENT FCST IS IN FAIRLY GOOD SHAPE...SO ONLY RELATIVELY
SMALL CHGS WERE MADE ATTM.
RGNL RADAR IMAGERY SHOWS A NARROW BAND OF LGT PCPN (MAINLY -SN)
EXTENDING FROM CNTRL IL-NRN IN-NRN OH-NW PA THIS EVE. THE LATEST
RUC-13 AND HRRR OUTPUT APPEAR TO BE DOING A REASONABLY GOOD JOB
HANDLING THE EVOLUTION OF THIS PCPN SO FAR. BOTH MODELS SUGGEST IT
WILL STREAK INTO THE TWIN TIERS BY 06-09Z...THEN EXIT BY ARND 15Z
SUN MRNG...UNDERNEATH DECENT 850-700 MB FGEN FORCING. THE MAIN
FACTORS GOING AGAINST PCPN DVLPMT LOCALLY ARE DRY LOW-LVL AIR TO
OVERCOME INITIALLY...AND ALSO NON-DESCRIPT JET DYNAMICS.
OVERALL...WE FELT THE COURSE OF LEAST REGRET WAS TO BUMP POPS UP
TO LIKELY VALUES WHERE WE HAVE SOME LGT SNOW ACCUMS MENTIONED LTR
TNT INTO EARLY SUN (MOSTLY ACRS NY`S SRN TIER...WITH MAX AMTS
GENERALLY 1" OR LESS). SHSN SHOULD DIMINISH QUICKLY TO FLRYS LTR
SUN MRNG...THEN END ALTOGETHER BY MIDDAY.
OTHWS...OUR TEMP/DEW PT GRIDS WERE MASSAGED SLIGHTLY THIS EVE...TO
BEST REFLECT THE LATEST OBSERVATIONAL TRENDS.
PREV DISC... 330 PM UPDATE...
WEAK DISTURBANCE OVER THE OHIO VALLEY CREATING LIGHT PRECIPITATION
OVER IL/IN WILL MOVE OUR WAY TONIGHT. I FOUND ONE OB TO THE WEST
SHOWING 2 1/2SM IN SNOW. BASED ON THIS AND MODEL QPF...NOT
EXPECTING MUCH MORE THAN A LIGHT DUSTING OF SNOW TONIGHT
ESPECIALLY NEAR OR JUST NORTH OF THE NY/PA LINE.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY/...
330 PM UPDATE...
DISTURBANCE ABOVE MAY CONTINUE A FEW SNOW SHOWERS INTO MIDDAY
SUNDAY BEFORE ENDING AS A SPRINKLE OR FLURRY. NOT EXPECTING MUCH.
BIGGER STORY WILL BE MUCH COLDER AIR BUILDING IN SUNDAY NIGHT AND
LASTING THROUGH TUESDAY. LAKE SNOWS LOOK LIKELY WITH A FLOW
SETTLING IN BETWEEN 290 AND 270. ONE LIMITING FACTOR AT LEAST
DURING THE DAY MAY DIURNAL EFFECTS. TAKE MONDAY AFTERNOON FOR
EXAMPLE WITH NAM BUFKIT PROFILES SHOWING SURFACE BASED CAPE OF
ABOVE 40 J/KG. BASED ON LOCAL RESEARCH, THESE VALUES COUPLED WITH
LOW TO MODERATE SHEAR WOULD PROMOTE MORE OF A DIFFUSE BAND OR OPEN
CELLULAR SNOW SHOWERS DURING THE AFTERNOON THAN A WELL DEFINED
BAND. WITH THAT IN MIND TRIED TO SHOW THE BEST ACCUMS OF AT LEAST
A FEW INCHES DURING THE NIGHTTIME AND EARLY PART OF THE DAY. COULD
SEE NEEDING AN ADVISORY AT SOME POINT DOWN THE ROAD BUT A WARNING
DOES NOT SEEM LIKELY...THUS AFTER COORDINATION WITH BUFFALO NO
LAKE EFFECT WATCH AT THIS POINT. HIGHS GENERALLY IN THE 20S
THROUGH TUESDAY. I DIDN`T TOUCH TUESDAYS HIGHS OF IN THE 20S. I
DID NOTICE MODEL GUIDANCE, ALMOST ALL OF IT, IS IN THE TEENS. WILL
BE INTERESTING TO SEE WHAT HAPPENS AS 925S SUPPORT OUR HIGHS OF 20S.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
MEDIUM RANGE MODELS CONTINUE TO SHOW EXCELLENT AGREEMENT THROUGH
THE EXTENDED PERIOD BOTH ALOFT AND AT THE SFC. IN GENERAL THE
PERIOD WILL BE VERY COLD WITH TEMPS RUNNING 15 TO 25 DEGREES
BELOW SEASONAL NORMALS. TUESDAY NIGHT INTO WED, MODELS INDICATE SFC
LOW PRES WELL OFF THE MID ATLANTIC COAST WITH THE GFS FURTHER OUT
TO SEA THAN THE ECMWF. CURRENT MODEL TREND IS FOR AN EVEN MORE
EASTERLY TRACK SO WILL CONTINUE WITH JUST CHC POPS THROUGH THIS
PERIOD. REST OF FORECAST LOOKS PRIMARILY DRY WITH SCATTERED LAKE
EFFECT SNOW SHOWERS AND FLURRIES EAST/SOUTHEAST OF LAKE ONTARIO.
&&
.AVIATION /02Z SUNDAY THROUGH THURSDAY/...
630 PM UPDATE...
SCT/BKN MID LEVEL CLOUDS WILL CONTINUE THIS EVENING. A WEAK
DISTURBANCE WILL MOVE THROUGH PA OVERNIGHT WITH THE MODELS
CONTINUING TO SUGGEST THE POTENTIAL FOR A NARROW BAND OF LIGHT
SNOW OVER THE SOUTHERN TIER LATE TONIGHT AND EARLY SUNDAY MORNING.
OVERALL CONFIDENCE WITH EXACT PLACEMENT AND TIMING OF SENSIBLE
WEATHER IS LOW. POTENTIAL FOR MVFR CONDITIONS IN LIGHT SNOW AT
KELM/KBGM/KITH LATE TONIGHT. ON SUNDAY LOW END VFR CONDITIONS ARE
EXPECTED.
GUSTY WEST WINDS WILL SUBSIDE QUICKLY. STILL GUSTING TO AROUND 25
KTS NOW AT SYR/RME WILL LAST UNTIL 02Z. TONIGHT SW TO W WINDS AT 5
TO 10 KTS. SUNDAY WEST WINDS AT 10 KTS.
OUTLOOK...
SUN NGT THROUGH TUE ATN...MVFR/IFR RESTRICTIONS IN LAKE EFFECT
-SHSN CNTRL NY TERMINALS.
TUE NGT THROUGH THU...RESTRICTIONS POSSIBLE IN SCATTERED SNOW
SHWRS.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...HEDEN
NEAR TERM...HEDEN/MLJ
SHORT TERM...HEDEN
LONG TERM...RRM
AVIATION...TAC
AREA FORECAST DISCUSSION
NWS RALEIGH NC
330 PM EST FRI FEB 21 2014
.SYNOPSIS...A STRONG COLD FRONT WILL PUSH SOUTH AND EAST OF THE AREA THIS EVENING.
HIGH PRESSURE WILL BUILD IN FROM THE SOUTHWEST TONIGHT AND SATURDAY...THEN DRIFT
EAST AND OFFSHORE ON SUNDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 300 PM FRIDAY...
QLCS CURRENTLY EXITING THE CWA AND WILL PLAN TO CANCEL TORNADO WATCH
23 FOR OUR COUNTIES WITH THE AFTERNOON PACKAGE. THE SYNOPTIC COLD
FRONT WILL MAKING ITS WAY THROUGH THE WESTERN PIEDMONT RIGHT NOW AND
WILL PUSH EAST THROUGH THE CWA BY AROUND 00Z. RH CROSS-SECTIONS
SUGGEST THERE MAY BE JUST ENOUGH SHALLOW MOISTURE CONVERGENCE ALONE
THE FRONT FOR A FEW ISOLATED SHOWERS. RECENT HRRR RUNS HAVEN`T BEEN
EXTREMELY CONSISTENT WITH THE COVERAGE OF ANY ADDITIONAL
SHOWERS...BUT WE WILL MAINTAIN JUST A SLIGHT CHANCE POP UNTIL HE
FRONT CLEARS THE AREA. OTHERWISE...MUCH DRIER AIR WILL FILTER INTO
THE AREA BEHIND THE FRONT ...WITH DEWPOINTS DROPPING INTO THE 20S.
HIGH PRESSURE RIDGING IN FROM THE WEST WILL ALLOW WESTERN AREAS TO
RADIATE THE BEST UNDER CLEAR SKIES...WITH LOWS DIPPING INTO THE MID
30S TO NEAR 40.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 300 PM FRIDAY...
WELL SOUTH OF THE DEEP POLAR VORTEX OVER SOUTHEAST CANADA... THE
CAROLINAS WILL LIE UNDER THE INFLUENCE OF BROAD WESTERLY CYCLONIC
FLOW ALOFT. AT THE SURFACE...HIGH PRESSURE OF PACIFIC ORIGINS WILL
BRIEFLY BUILD OVER THE SOUTHEAST US ON SATURDAY... SHIFTING OFFSHORE
SATURDAY NIGHT WITH SOUTHERLY RETURN FLOW SUNDAY BEFORE A DRY
SURFACE COLD FRONT MOVES SOUTHEASTWARD THROUGH THE AREA SUNDAY
EVENING.
THIS WILL TRANSLATE INTO TO DRY CONDITIONS WITH CONTINUED SPRING-
LIKE TEMPERATURES INTO THE 60S ON SATURDAY...WITH SOME UPPER 60S TO
LOWER 70S ON SUNDAY. LOWS SATURDAY NIGHT IN THE 40S...COOLING OFF
INTO THE 30S BEHIND THE FRONT SUNDAY NIGHT.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 300 PM FRIDAY...
DRY CONDITIONS WILL CONTINUE INTO MONDAY...ALBEIT WITH COOLER-MORE
SEASONABLE TEMPERATURES AS A PROGRESSIVE NORTHERN STREAM HIGH OVER
THE CENTRAL US BUILDS EASTWARD INTO THE AREA.
TUESDAY THROUGH WEDNESDAY...AN EVEN STRONGER POLAR VORTEX DROPPING
SOUTHEASTWARD INTO SOUTHERN CANADA WILL RESULT IN A SIGNIFICANT
PATTERN CHANGE WITH A DEEP UPPER TROUGH FORECAST TO DEVELOP EAST OF
THE ROCKIES. WHILE THE OVERALL PATTERN IS HIGHLY AGREED UPON...THERE
IS STILL A FAIR AMOUNT OF UNCERTAINTY THATS LARGELY OWED TO THE
TIMING OF THE MID-LEVEL ENERGY EJECTING EASTWARD FROM THE CENTRAL
ROCKIES...AND TO A LESSER EXTENT...WEAK S/W IMPULSES OUT AHEAD OF
THE LEAD TROUGH THAT WILL EVENTUALLY RESULT IN SURFACE CYCLOGENESIS
ALONG A BAROCLINIC FRONTAL ZONE EXTENDING FROM THE GULF OF MEXICO TO
THE SE COAST. INCREASING RAIN CHANCES TUESDAY THROUGH
WEDNESDAY...WITH POPS/QPF DEPENDING ON TRACK/LOCATION OF COASTAL LOW
AND ALL LIQUID AT THIS TIME AS SIGNIFICANTLY COLDER AIR ARRIVES
THURSDAY THROUGH FRIDAY.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
AS OF 1250 PM FRIDAY...
LINE OF CONVECTION MOVING THROUGH CENTRAL NC CURRENTLY EXTENDS FROM
KIXA TO EAST OF KRDU TO KFAY. WITHIN THE LINE..CEILINGS ARE
LIFR/IFR...WITH HEAVY RAIN AND LIFR VSBYS ARE TIMES. WINDS JUST
AHEAD WITHIN STRONGER STORMS WILL GUST TO 30-40KT..MOSTLY FROM THE
WEST-SOUTHWEST. THE LINE IS EXPECTED TO MOVE EAST OF I-95 WITHIN
THE NEXT HOUR OR TWO AND BE CLEAR OF THE AREA BY 21Z. WEST OF THE
LINE...SOME LIGHT RAIN IS STILL FALLING AND CEILINGS ARE MOSTLY MVFR
OR VFR. THE COLD FRONT ASSOCIATED WITH THIS SYSTEM HAS MOVED
THROUGH KGSO AND KINT...WHERE WINDS FROM THE NORTHWEST GUSTED TO
30KT. THIS WILL BE POSSIBLE AT KRDU...KFAY AND KINT BY 20-22Z AS
THE FRONT PUSHES EAST. SKIES WILL THEN CLEAR BEHIND THE FRONT AND
VFR CONDITIONS ARE EXPECTED THROUGH THE REMAINDER OF THE TAF PERIOD.
OUTLOOK... A DRY COLD FRONT WILL MOVE THROUGH THE AREA SUNDAY
NIGHT...WITH ONLY A SMALL CHANCE OF SUB-VFR CONDITIONS. OTHERWISE...
VFR CONDITIONS ARE EXPECTED THROUGH EARLY TUESDAY WHEN ANOTHER
WEATHER SYSTEM IS EXPECTED TO IMPACT THE REGION.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...WSS
NEAR TERM...SMITH
SHORT TERM..CBL
LONG TERM...CBL
AVIATION...SMITH
AREA FORECAST DISCUSSION
NWS RALEIGH NC
303 PM EST FRI FEB 21 2014
.SYNOPSIS...A STRONG COLD FRONT WILL PUSH SOUTH AND EAST OF THE AREA THIS EVENING.
HIGH PRESSURE WILL BUILD IN FROM THE SOUTHWEST TONIGHT AND SATURDAY...THEN DRIFT
EAST AND OFFSHORE ON SUNDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 300 PM FRIDAY...
QLCS CURRENTLY EXITING THE CWA AND WILL PLAN TO CANCEL TORNADO WATCH
23 FOR OUR COUNTIES WITH THE AFTERNOON PACKAGE. THE SYNOPTIC COLD
FRONT WILL MAKING ITS WAY THROUGH THE WESTERN PIEDMONT RIGHT NOW AND
WILL PUSH EAST THROUGH THE CWA BY AROUND 00Z. RH CROSS-SECTIONS
SUGGEST THERE MAY BE JUST ENOUGH SHALLOW MOISTURE CONVERGENCE ALONE
THE FRONT FOR A FEW ISOLATED SHOWERS. RECENT HRRR RUNS HAVEN`T BEEN
EXTREMELY CONSISTENT WITH THE COVERAGE OF ANY ADDITIONAL
SHOWERS...BUT WE WILL MAINTAIN JUST A SLIGHT CHANCE POP UNTIL HE
FRONT CLEARS THE AREA. OTHERWISE...MUCH DRIER AIR WILL FILTER INTO
THE AREA BEHIND THE FRONT ...WITH DEWPOINTS DROPPING INTO THE 20S.
HIGH PRESSURE RIDGING IN FROM THE WEST WILL ALLOW WESTERN AREAS TO
RADIATE THE BEST UNDER CLEAR SKIES...WITH LOWS DIPPING INTO THE MID
30S TO NEAR 40.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 304 AM FRIDAY...
HIGH PRESSURE WILL BUILD ACROSS THE AREA IN THE WAKE OF THE FRONT...
AND A MUCH DRIER AIRMASS WILL BE IN PLACE ACROSS THE AREA BRINGING
MOSTLY SUNNY SKIES. INITIAL COLD ADVECTION EARLY SATURDAY WILL
BECOME NEUTRAL... AS UPPER LEVEL FLOW REMAINS PRIMARILY
SOUTHWESTERLY DURING THE DAY SATURDAY... AND TEMPERATURES WILL
REMAIN A FEW DEGREES ABOVE NORMAL.
HIGH PRESSURE WILL MOVE OFFSHORE SUNDAY... WARMER SOUTHERLY FLOW...
AND INCREASING LOW LEVEL THICKNESSES WILL RESULT IN TEMPERATURES
SLIGHTLY WARMER THAN SATURDAY.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 305 AM FRIDAY...
A DRY COLD FRONT WILL MOVE THROUGH THE AREA MONDAY MORNING...
BRINGING TEMPERATURES MUCH CLOSER TO NORMAL FOR THE BEGINNING OF THE
WEEK.
STRONG SIGNAL FOR RIDGING ACROSS THE WESTERN US... WITH BROAD
TROUGHING DEVELOPING OVER THE EAST COAST THROUGH THE WEEK. THIS WILL
BRING TEMPS BACK BELOW NORMAL. WAVES MOVING THROUGH THE NORTHWEST
FLOW GENERALLY STAY NORTH OF OUR AREA THROUGH THIS PERIOD... WITH
THE EXCEPTION OF WEDNESDAY WHEN A AN IMPULSE AND ASSOCIATED COLD
FRONT ARE PROGGED TO MOVE THROUGH THE AREA... AND THE POTENTIAL FOR
A LOW PRESSURE SYSTEM TO DEVELOP OFF THE CAROLINA COAST... BRINGING
THE BEST CHANCE FOR PRECIPITATION DURING THIS PERIOD.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
AS OF 1250 PM FRIDAY...
LINE OF CONVECTION MOVING THROUGH CENTRAL NC CURRENTLY EXTENDS FROM
KIXA TO EAST OF KRDU TO KFAY. WITHIN THE LINE..CEILINGS ARE
LIFR/IFR...WITH HEAVY RAIN AND LIFR VSBYS ARE TIMES. WINDS JUST
AHEAD WITHIN STRONGER STORMS WILL GUST TO 30-40KT..MOSTLY FROM THE
WEST-SOUTHWEST. THE LINE IS EXPECTED TO MOVE EAST OF I-95 WITHIN
THE NEXT HOUR OR TWO AND BE CLEAR OF THE AREA BY 21Z. WEST OF THE
LINE...SOME LIGHT RAIN IS STILL FALLING AND CEILINGS ARE MOSTLY MVFR
OR VFR. THE COLD FRONT ASSOCIATED WITH THIS SYSTEM HAS MOVED
THROUGH KGSO AND KINT...WHERE WINDS FROM THE NORTHWEST GUSTED TO
30KT. THIS WILL BE POSSIBLE AT KRDU...KFAY AND KINT BY 20-22Z AS
THE FRONT PUSHES EAST. SKIES WILL THEN CLEAR BEHIND THE FRONT AND
VFR CONDITIONS ARE EXPECTED THROUGH THE REMAINDER OF THE TAF PERIOD.
OUTLOOK... A DRY COLD FRONT WILL MOVE THROUGH THE AREA SUNDAY
NIGHT...WITH ONLY A SMALL CHANCE OF SUB-VFR CONDITIONS. OTHERWISE...
VFR CONDITIONS ARE EXPECTED THROUGH EARLY TUESDAY WHEN ANOTHER
WEATHER SYSTEM IS EXPECTED TO IMPACT THE REGION.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...WSS
NEAR TERM...SMITH
SHORT TERM..SEC
LONG TERM...SEC
AVIATION...SMITH
AREA FORECAST DISCUSSION
NWS NORMAN OK
1100 AM CST FRI FEB 21 2014
.AVIATION...
GUSTY SOUTH WINDS WILL CONTINUE THIS AFTERNOON BEFORE DYING DOWN
AFTER SUNSET. OTHERWISE...VFR CONDITIONS EXPECTED THROUGH THE TAF
PERIOD.
&&
.PREV DISCUSSION... /ISSUED 1033 AM CST FRI FEB 21 2014/
DISCUSSION...
WINDS AND TEMPERATURES ARE INCREASING RAPIDLY THIS MORNING AS THE
SHALLOW SURFACE INVERSION MIXES OUT. IT APPEARS THAT WE WILL START
SEEING RED FLAG WARNING CRITERIA BEING MET AROUND NOON...AS
PLANNED.
ALL FEATURES OF THE FORECAST APPEAR TO BE IN GOOD SHAPE
AT THIS TIME...AND NO CHANGES ARE PLANNED FOR THIS MORNING.
PREV DISCUSSION... /ISSUED 527 AM CST FRI FEB 21 2014/
DISCUSSION...
AVIATION DISCUSSION FOR THE 12Z TAFS IS BELOW.
AVIATION...
VFR CONDITIONS ARE EXPECTED TO CONTINUE.
SOUTH TO SOUTHWEST WINDS WILL INCREASE AND BECOME GUSTY
AT ALL SITES BY 17Z. THESE WINDS WILL SUBSIDE AROUND 00Z.
MBS
PREV DISCUSSION... /ISSUED 404 AM CST FRI FEB 21 2014/
DISCUSSION...
THE MAIN CONCERN IS CRITICAL FIRE WEATHER CONDITIONS TODAY.
MOSTLY TO PARTLY SUNNY SKIES AND MILDER WEATHER WILL OCCUR TODAY.
WINDS WILL BE WEAKER THAN YESTERDAY...THOUGH BREEZY. PREFERRED THE
WARMER SIDE OF GUIDANCE HIGHS TODAY WITH A GOOD AMOUNT OF SUN AND
DRY GROUND...GENERALLY FROM THE LOWER 60S NEAR THE KANSAS OKLAHOMA
STATE LINE TO THE MID 70S IN FAR WESTERN NORTH TEXAS. WENT ABOVE
MODEL GUIDANCE WIND SPEEDS AND BELOW MOST MODEL GUIDANCE
DEWPOINTS. A FEW GUSTS MAY APPROACH 40 MPH IN WESTERN OKLAHOMA
AROUND MIDDAY TODAY. THE LOWER SURFACE DEWPOINTS DEPICTED BY
LATEST HRRR RUNS WERE USED TODAY AS OTHER MODELS SEEM TO BE
OVERESTIMATING THE AMOUNT OF LOW LEVEL MOISTURE.
DRY AND MILD WEATHER WILL CONTINUE INTO SATURDAY UNDER MOSTLY TO
PARTLY SUNNY. LESS WIND IS FORECAST COMPARED TO TODAY.
SATURDAY NIGHT INTO SUNDAY...LOW LEVEL MOISTURE WILL INCREASE
ACROSS THE AREA. ADDED PATCHY FOG MENTION NEAR AND SOUTHEAST OF
A DEVELOPING SURFACE TROUGH/COLD FRONT...ROUGHLY NEAR AND
SOUTHEAST OF I-44. THINK MOISTURE WILL BE TOO SHALLOW FOR
ANY MEASURABLE RAINFALL OF 0.01 INCH OR MORE. COOLER TEMPERATURES
WILL RESULT ON SUNDAY AS THE COLD FRONT SURGES SOUTH.
MONDAY THROUGH TUESDAY...KEPT LOW SHOWER/STORM CHANCES OVER
SOUTHERN OKLAHOMA AND WESTERN NORTH TEXAS AS ISENTROPIC LIFT
COMBINED WITH SOME ELEVATED INSTABILITY MAY ALLOW FOR DEVELOPMENT
OF CONVECTIVE LIQUID PRECIPITATION JUST NORTH OF A WARM FRONT.
CONFIDENCE WITH THIS SYSTEM REMAINS LOW. HIGHS WILL BE BELOW
AVERAGE.
WEDNESDAY AND THURSDAY...BELOW AVERAGE TEMPERATURES AND DRY
WEATHER ARE FORECAST. DID NOT MAKE ANY SIGNIFICANT CHANGES TO THE
PREVIOUS FORECAST.
MBS
FIRE WEATHER...
UPGRADED THE ENTIRE FIRE WEATHER WATCH TO A RED FLAG WARNING
AND INCLUDED MANY COUNTIES IN NORTHERN OKLAHOMA AS THESE LOCATIONS
WILL BE NEAR 65 DEGREES TODAY. STARTED THE RED FLAG WARNING AT
10 AM TODAY AS POOR HUMIDITY RECOVERY EARLY THIS MORNING WILL
ALLOW FOR RED FLAG CONDITIONS TO DEVELOP FASTER THAN PREVIOUSLY
FORECAST.
MBS
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 39 66 42 52 / 0 0 0 10
HOBART OK 38 70 41 52 / 0 0 0 0
WICHITA FALLS TX 43 76 47 61 / 0 0 0 0
GAGE OK 21 63 34 46 / 0 0 0 0
PONCA CITY OK 35 60 36 47 / 0 0 10 10
DURANT OK 44 70 52 61 / 0 0 10 10
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...RED FLAG WARNING UNTIL 6 PM CST THIS EVENING FOR OKZ005>030-
033>040-044-045.
TX...RED FLAG WARNING UNTIL 6 PM CST THIS EVENING FOR TXZ083>090.
&&
$$
23/84/14
AREA FORECAST DISCUSSION
NWS NORMAN OK
1033 AM CST FRI FEB 21 2014
.DISCUSSION...
WINDS AND TEMPERATURES ARE INCREASING RAPIDLY THIS MORNING AS THE
SHALLOW SURFACE INVERSION MIXES OUT. IT APPEARS THAT WE WILL START
SEEING RED FLAG WARNING CRITERIA BEING MET AROUND NOON...AS
PLANNED.
ALL FEATURES OF THE FORECAST APPEAR TO BE IN GOOD SHAPE
AT THIS TIME...AND NO CHANGES ARE PLANNED FOR THIS MORNING.
&&
.PREV DISCUSSION... /ISSUED 527 AM CST FRI FEB 21 2014/
DISCUSSION...
AVIATION DISCUSSION FOR THE 12Z TAFS IS BELOW.
AVIATION...
VFR CONDITIONS ARE EXPECTED TO CONTINUE.
SOUTH TO SOUTHWEST WINDS WILL INCREASE AND BECOME GUSTY
AT ALL SITES BY 17Z. THESE WINDS WILL SUBSIDE AROUND 00Z.
MBS
PREV DISCUSSION... /ISSUED 404 AM CST FRI FEB 21 2014/
DISCUSSION...
THE MAIN CONCERN IS CRITICAL FIRE WEATHER CONDITIONS TODAY.
MOSTLY TO PARTLY SUNNY SKIES AND MILDER WEATHER WILL OCCUR TODAY.
WINDS WILL BE WEAKER THAN YESTERDAY...THOUGH BREEZY. PREFERRED THE
WARMER SIDE OF GUIDANCE HIGHS TODAY WITH A GOOD AMOUNT OF SUN AND
DRY GROUND...GENERALLY FROM THE LOWER 60S NEAR THE KANSAS OKLAHOMA
STATE LINE TO THE MID 70S IN FAR WESTERN NORTH TEXAS. WENT ABOVE
MODEL GUIDANCE WIND SPEEDS AND BELOW MOST MODEL GUIDANCE
DEWPOINTS. A FEW GUSTS MAY APPROACH 40 MPH IN WESTERN OKLAHOMA
AROUND MIDDAY TODAY. THE LOWER SURFACE DEWPOINTS DEPICTED BY
LATEST HRRR RUNS WERE USED TODAY AS OTHER MODELS SEEM TO BE
OVERESTIMATING THE AMOUNT OF LOW LEVEL MOISTURE.
DRY AND MILD WEATHER WILL CONTINUE INTO SATURDAY UNDER MOSTLY TO
PARTLY SUNNY. LESS WIND IS FORECAST COMPARED TO TODAY.
SATURDAY NIGHT INTO SUNDAY...LOW LEVEL MOISTURE WILL INCREASE
ACROSS THE AREA. ADDED PATCHY FOG MENTION NEAR AND SOUTHEAST OF
A DEVELOPING SURFACE TROUGH/COLD FRONT...ROUGHLY NEAR AND
SOUTHEAST OF I-44. THINK MOISTURE WILL BE TOO SHALLOW FOR
ANY MEASURABLE RAINFALL OF 0.01 INCH OR MORE. COOLER TEMPERATURES
WILL RESULT ON SUNDAY AS THE COLD FRONT SURGES SOUTH.
MONDAY THROUGH TUESDAY...KEPT LOW SHOWER/STORM CHANCES OVER
SOUTHERN OKLAHOMA AND WESTERN NORTH TEXAS AS ISENTROPIC LIFT
COMBINED WITH SOME ELEVATED INSTABILITY MAY ALLOW FOR DEVELOPMENT
OF CONVECTIVE LIQUID PRECIPITATION JUST NORTH OF A WARM FRONT.
CONFIDENCE WITH THIS SYSTEM REMAINS LOW. HIGHS WILL BE BELOW
AVERAGE.
WEDNESDAY AND THURSDAY...BELOW AVERAGE TEMPERATURES AND DRY
WEATHER ARE FORECAST. DID NOT MAKE ANY SIGNIFICANT CHANGES TO THE
PREVIOUS FORECAST.
MBS
FIRE WEATHER...
UPGRADED THE ENTIRE FIRE WEATHER WATCH TO A RED FLAG WARNING
AND INCLUDED MANY COUNTIES IN NORTHERN OKLAHOMA AS THESE LOCATIONS
WILL BE NEAR 65 DEGREES TODAY. STARTED THE RED FLAG WARNING AT
10 AM TODAY AS POOR HUMIDITY RECOVERY EARLY THIS MORNING WILL
ALLOW FOR RED FLAG CONDITIONS TO DEVELOP FASTER THAN PREVIOUSLY
FORECAST.
MBS
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 66 39 66 42 / 0 0 0 0
HOBART OK 68 38 70 41 / 0 0 0 0
WICHITA FALLS TX 71 43 76 47 / 0 0 0 0
GAGE OK 64 21 63 34 / 0 0 0 0
PONCA CITY OK 63 35 60 36 / 0 0 0 10
DURANT OK 65 44 70 52 / 0 0 0 10
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...RED FLAG WARNING UNTIL 6 PM CST THIS EVENING FOR OKZ005>030-
033>040-044-045.
TX...RED FLAG WARNING UNTIL 6 PM CST THIS EVENING FOR TXZ083>090.
&&
$$
23/84
AREA FORECAST DISCUSSION
NWS NORMAN OK
527 AM CST FRI FEB 21 2014
.DISCUSSION...
AVIATION DISCUSSION FOR THE 12Z TAFS IS BELOW.
&&
.AVIATION...
VFR CONDITIONS ARE EXPECTED TO CONTINUE.
SOUTH TO SOUTHWEST WINDS WILL INCREASE AND BECOME GUSTY
AT ALL SITES BY 17Z. THESE WINDS WILL SUBSIDE AROUND 00Z.
MBS
&&
.PREV DISCUSSION... /ISSUED 404 AM CST FRI FEB 21 2014/
DISCUSSION...
THE MAIN CONCERN IS CRITICAL FIRE WEATHER CONDITIONS TODAY.
MOSTLY TO PARTLY SUNNY SKIES AND MILDER WEATHER WILL OCCUR TODAY.
WINDS WILL BE WEAKER THAN YESTERDAY...THOUGH BREEZY. PREFERRED THE
WARMER SIDE OF GUIDANCE HIGHS TODAY WITH A GOOD AMOUNT OF SUN AND
DRY GROUND...GENERALLY FROM THE LOWER 60S NEAR THE KANSAS OKLAHOMA
STATE LINE TO THE MID 70S IN FAR WESTERN NORTH TEXAS. WENT ABOVE
MODEL GUIDANCE WIND SPEEDS AND BELOW MOST MODEL GUIDANCE
DEWPOINTS. A FEW GUSTS MAY APPROACH 40 MPH IN WESTERN OKLAHOMA
AROUND MIDDAY TODAY. THE LOWER SURFACE DEWPOINTS DEPICTED BY
LATEST HRRR RUNS WERE USED TODAY AS OTHER MODELS SEEM TO BE
OVERESTIMATING THE AMOUNT OF LOW LEVEL MOISTURE.
DRY AND MILD WEATHER WILL CONTINUE INTO SATURDAY UNDER MOSTLY TO
PARTLY SUNNY. LESS WIND IS FORECAST COMPARED TO TODAY.
SATURDAY NIGHT INTO SUNDAY...LOW LEVEL MOISTURE WILL INCREASE
ACROSS THE AREA. ADDED PATCHY FOG MENTION NEAR AND SOUTHEAST OF
A DEVELOPING SURFACE TROUGH/COLD FRONT...ROUGHLY NEAR AND
SOUTHEAST OF I-44. THINK MOISTURE WILL BE TOO SHALLOW FOR
ANY MEASURABLE RAINFALL OF 0.01 INCH OR MORE. COOLER TEMPERATURES
WILL RESULT ON SUNDAY AS THE COLD FRONT SURGES SOUTH.
MONDAY THROUGH TUESDAY...KEPT LOW SHOWER/STORM CHANCES OVER
SOUTHERN OKLAHOMA AND WESTERN NORTH TEXAS AS ISENTROPIC LIFT
COMBINED WITH SOME ELEVATED INSTABILITY MAY ALLOW FOR DEVELOPMENT
OF CONVECTIVE LIQUID PRECIPITATION JUST NORTH OF A WARM FRONT.
CONFIDENCE WITH THIS SYSTEM REMAINS LOW. HIGHS WILL BE BELOW
AVERAGE.
WEDNESDAY AND THURSDAY...BELOW AVERAGE TEMPERATURES AND DRY
WEATHER ARE FORECAST. DID NOT MAKE ANY SIGNIFICANT CHANGES TO THE
PREVIOUS FORECAST.
MBS
FIRE WEATHER...
UPGRADED THE ENTIRE FIRE WEATHER WATCH TO A RED FLAG WARNING
AND INCLUDED MANY COUNTIES IN NORTHERN OKLAHOMA AS THESE LOCATIONS
WILL BE NEAR 65 DEGREES TODAY. STARTED THE RED FLAG WARNING AT
10 AM TODAY AS POOR HUMIDITY RECOVERY EARLY THIS MORNING WILL
ALLOW FOR RED FLAG CONDITIONS TO DEVELOP FASTER THAN PREVIOUSLY
FORECAST.
MBS
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 66 39 66 42 / 0 0 0 0
HOBART OK 68 38 70 41 / 0 0 0 0
WICHITA FALLS TX 71 43 76 47 / 0 0 0 0
GAGE OK 64 21 63 34 / 0 0 0 0
PONCA CITY OK 63 35 60 36 / 0 0 0 10
DURANT OK 65 44 70 52 / 0 0 0 10
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...RED FLAG WARNING FROM 10 AM THIS MORNING TO 6 PM CST THIS
EVENING FOR OKZ005>030-033>040-044-045.
TX...RED FLAG WARNING FROM 10 AM THIS MORNING TO 6 PM CST THIS
EVENING FOR TXZ083>090.
&&
$$
03/17/17
AREA FORECAST DISCUSSION
NWS NORMAN OK
404 AM CST FRI FEB 21 2014
.DISCUSSION...
THE MAIN CONCERN IS CRITICAL FIRE WEATHER CONDITIONS TODAY.
MOSTLY TO PARTLY SUNNY SKIES AND MILDER WEATHER WILL OCCUR TODAY.
WINDS WILL BE WEAKER THAN YESTERDAY...THOUGH BREEZY. PREFERRED THE
WARMER SIDE OF GUIDANCE HIGHS TODAY WITH A GOOD AMOUNT OF SUN AND
DRY GROUND...GENERALLY FROM THE LOWER 60S NEAR THE KANSAS OKLAHOMA
STATE LINE TO THE MID 70S IN FAR WESTERN NORTH TEXAS. WENT ABOVE
MODEL GUIDANCE WIND SPEEDS AND BELOW MOST MODEL GUIDANCE
DEWPOINTS. A FEW GUSTS MAY APPROACH 40 MPH IN WESTERN OKLAHOMA
AROUND MIDDAY TODAY. THE LOWER SURFACE DEWPOINTS DEPICTED BY
LATEST HRRR RUNS WERE USED TODAY AS OTHER MODELS SEEM TO BE
OVERESTIMATING THE AMOUNT OF LOW LEVEL MOISTURE.
DRY AND MILD WEATHER WILL CONTINUE INTO SATURDAY UNDER MOSTLY TO
PARTLY SUNNY. LESS WIND IS FORECAST COMPARED TO TODAY.
SATURDAY NIGHT INTO SUNDAY...LOW LEVEL MOISTURE WILL INCREASE
ACROSS THE AREA. ADDED PATCHY FOG MENTION NEAR AND SOUTHEAST OF
A DEVELOPING SURFACE TROUGH/COLD FRONT...ROUGHLY NEAR AND
SOUTHEAST OF I-44. THINK MOISTURE WILL BE TOO SHALLOW FOR
ANY MEASURABLE RAINFALL OF 0.01 INCH OR MORE. COOLER TEMPERATURES
WILL RESULT ON SUNDAY AS THE COLD FRONT SURGES SOUTH.
MONDAY THROUGH TUESDAY...KEPT LOW SHOWER/STORM CHANCES OVER
SOUTHERN OKLAHOMA AND WESTERN NORTH TEXAS AS ISENTROPIC LIFT
COMBINED WITH SOME ELEVATED INSTABILITY MAY ALLOW FOR DEVELOPMENT
OF CONVECTIVE LIQUID PRECIPITATION JUST NORTH OF A WARM FRONT.
CONFIDENCE WITH THIS SYSTEM REMAINS LOW. HIGHS WILL BE BELOW
AVERAGE.
WEDNESDAY AND THURSDAY...BELOW AVERAGE TEMPERATURES AND DRY
WEATHER ARE FORECAST. DID NOT MAKE ANY SIGNIFICANT CHANGES TO THE
PREVIOUS FORECAST.
MBS
&&
.FIRE WEATHER...
UPGRADED THE ENTIRE FIRE WEATHER WATCH TO A RED FLAG WARNING
AND INCLUDED MANY COUNTIES IN NORTHERN OKLAHOMA AS THESE LOCATIONS
WILL BE NEAR 65 DEGREES TODAY. STARTED THE RED FLAG WARNING AT
10 AM TODAY AS POOR HUMIDITY RECOVERY EARLY THIS MORNING WILL
ALLOW FOR RED FLAG CONDITIONS TO DEVELOP FASTER THAN PREVIOUSLY
FORECAST.
MBS
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 66 39 66 42 / 0 0 0 0
HOBART OK 68 38 70 41 / 0 0 0 0
WICHITA FALLS TX 71 43 76 47 / 0 0 0 0
GAGE OK 64 21 63 34 / 0 0 0 0
PONCA CITY OK 63 35 60 36 / 0 0 0 10
DURANT OK 65 44 70 52 / 0 0 0 10
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...RED FLAG WARNING FROM 10 AM THIS MORNING TO 6 PM CST THIS
EVENING FOR OKZ005>030-033>040-044-045.
TX...RED FLAG WARNING FROM 10 AM THIS MORNING TO 6 PM CST THIS
EVENING FOR TXZ083>090.
&&
$$
03/17
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
244 PM CST FRI FEB 21 2014
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 244 PM CST FRI FEB 21 2014
MAIN FORECASTS CONCERNS ARE ON SNOW CHANCES MONDAY NIGHT. FOCUS
THEN TURNS TO BITTERLY COLD TEMPERATURES LATE NEXT WEEK.
LATEST SURFACE OBSERVATIONS AND REPORTS ACROSS THE AREA INDICATED
AREAS OF BLOWING AND DRIFTING SNOW...LEADING TO HAZARDOUS TRAVEL
CONDITIONS. THE WORST OF THE BLOWING AND DRIFTING SNOW WAS
OCCURRING WEST OF THE MISSISSIPPI RIVER. CONDITIONS ARE EXPECTED
TO IMPROVE LATE THIS AFTERNOON INTO EARLY THIS EVENING. THE
POTENT LOW PRESSURE SYSTEM RESPONSIBLE FOR THE STRONG
WEST/NORTHWEST WINDS WAS CENTERED OVER NORTH CENTRAL LAKE
SUPERIOR. THE LOW WILL LIFT NORTHEAST OF THE REGION TONIGHT AS
HIGH PRESSURE EDGES IN FROM THE NORTHERN PLAINS.
A PERSISTENT PRESSURE GRADIENT WILL REMAIN IN PLACE OVER THE UPPER
MISSISSIPPI RIVER VALLEY TONIGHT THROUGH SATURDAY CREATING WEST
WINDS OF 10 TO 17 MPH. THESE WINDS WILL MAKE IT FEEL CHILLY ON
SATURDAY WITH WIND CHILLS IN THE SINGLE DIGITS TO SINGLE DIGITS
BELOW ZERO. PLAN ON HIGH TEMPERATURES RANGING FROM THE MID TEENS TO
LOWER 20S.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 244 PM CST FRI FEB 21 2014
A CHILLY NIGHT IN STORE FOR THE AREA SATURDAY NIGHT WITH LOWS
RANGING ROM THE SINGLE DIGITS BELOW ZERO OVER SOUTHEAST MINNESOTA
THROUGH NORTH CENTRAL WISCONSIN TO THE SINGLE DIGITS ABOVE ZERO OVER
FAR SOUTHWEST WISCONSIN INTO NORTHEAST IOWA. WIND CHILL VALUES ARE
EXPECTED TO DIP INTO THE 20 TO 27 BELOW RANGE LATE SATURDAY NIGHT
INTO EARLY SUNDAY MORNING OVER NORTH CENTRAL WISCONSIN.
ELSEWHERE...PLAN ON WIND CHILLS FALLING INTO THE TEENS BELOW ZERO.
DRY...QUIET...AND CHILLY CONDITIONS WILL CONTINUE THROUGH SUNDAY
WITH HIGHS MAINLY IN THE TEENS AND LOWS IN THE SINGLE DIGITS BELOW
ZERO.
A SHORTWAVE TROUGH IS EXPECTED TO DROP INTO THE REGION FROM THE
NORTHERN PLAINS LATE MONDAY AFTERNOON INTO MONDAY NIGHT PRODUCING
LIGHT SNOW ACROSS AREA. AT THIS TIME...THE HIGHEST CHANCES FOR SNOW
LOOK TO BE SOUTH AND WEST OF THE INTERSTATE 94 CORRIDOR. LATEST
THINKING IS THAT SNOW ACCUMULATIONS SHOULD RANGE FROM 1 TO 3
INCHES...WITH THE HIGHER ACCUMULATIONS OCCURRING OVER NORTHEAST IOWA
INTO FAR SOUTHWEST WISCONSIN...BUT THIS DEPENDS ON THE EXACT STORM
TRACK. GIVEN THE CONSISTENT SIGNAL FOR SNOW OVER THESE AREAS HAVE
DECIDED TO INCREASE PRECIPITATION CHANCES.
A BITTERLY COLD ARCTIC AIRMASS MOVES BACK INTO THE REGION LATE
TUESDAY INTO WEDNESDAY WITH 850 MB TEMPERATURES PLUMMETING INTO THE
-22 TO -25 C RANGE. WIND CHILL VALUES OF 20 TO 25 BELOW ZERO LOOK
LIKELY TUESDAY NIGHT INTO WEDNESDAY MORNING AND A WIND CHILL
ADVISORY WILL LIKELY BE NEEDED. THE COLDEST TEMPERATURES ARE
EXPECTED TO SETTLE IN WEDNESDAY INTO THURSDAY WHEN LOWS LOOK TO FALL
INTO THE TEENS TO AROUND 20 BELOW ZERO. WIND CHILL HEADLINES APPEAR
LIKELY WEDNESDAY NIGHT AND AGAIN THURSDAY NIGHT...WHEN WIND CHILL
VALUES OF 20 TO 30 BELOW ZERO ARE EXPECTED. THURSDAY NIGHT LOOKS TO
HAVE THE COLDEST AIR TEMPERATURES WHEN LOWS WILL FALL INTO THE TEENS
TO AROUND 20 BELOW ZERO. 850 MB TEMPERATURE STANDARDIZED ANOMALIES
OF -2.0 TO -2.5 MOVE INTO THE REGION LATE THURSDAY NIGHT INTO
FRIDAY PUTTING US IN NEAR RECORD TERRITORY FOR THIS TIME OF YEAR.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1150 AM CST FRI FEB 21 2014
STRONG WEST WINDS AT 20 TO 30 WITH GUSTS TO 35 WILL PERSIST THROUGH
MUCH OF THE AFTERNOON HOURS...PER LATEST RAP SOUNDINGS. KRST/KLSE ON
CLEARING EDGE OF THE CLOUDS...VIA SFC OBS AND SATELLITE IMAGERY. OBS
MAY POINT TO SOME CIGS FROM BLOWING SNOW. GOING TO KEEP VSBY
RESTRICTIONS AT KRST THROUGH THE AFTERNOON. VFR CONDITIONS SHOULD BE
THE RULE TONIGHT INTO SATURDAY WITH SKC SKIES AND WINDS TAPERING
OFF INTO THE 10 TO 15 KT RANGE.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR WIZ017-
029-032>034-041>044-053>055-061.
MN...WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR MNZ079-
086>088-094>096.
IA...WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR
IAZ008>011-018-019-029-030.
&&
$$
SHORT TERM...WETENKAMP
LONG TERM...WETENKAMP
AVIATION.....RIECK
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1150 AM CST FRI FEB 21 2014
.UPDATED...
1150 AM CST FRI FEB 21 2014
MANY ROAD CLOSURES CONTINUE ACROSS SOUTHEAST MN AND NORTHEAST
IA...WITH A TOW BAN IN EFFECT FOR SOME LOCATIONS. WINDS ARE GOING TO
STAY STRONG AND GUSTY THROUGH THE AFTERNOON...WITH ANY SUNSHINE ONLY
HELPING MIX DOWN THE STRONG NEAR SFC WINDS. WILL LET THE WARNINGS
EXPIRE...BUT REPLACE WITH A WINTER WEATHER ADV FOR BLOWING/DRIFTING
SNOW FOR THE ENTIRE FORECAST AREA THROUGH 00Z. CONDITIONS STILL
WARRANT IT.
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 214 AM CST FRI FEB 21 2014
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED NORTHWEST FLOW FROM ALASKA DOWN INTO THE MID-MISSISSIPPI
RIVER VALLEY AND A DEEP UPPER LOW OVER NORTHERN WI. UNDERNEATH THE
UPPER LOW WAS A 978 MB SURFACE LOW NEAR RHINELANDER. A VERY TIGHT
PRESSURE GRADIENT SOUTHWEST OF THE LOW WAS SUPPORTING SURFACE WINDS
OF 25 TO 35 MPH WITH GUSTS UP TO 55 MPH. THE COLD CONVEYOR BELT
WRAPPING AROUND THE NEARLY VERTICALLY STACKED LOW WAS STILL BRINGING
SNOW TO THE FORECAST AREA...HEAVIEST OVER NORTH CENTRAL WI. EARLIER
LAST EVENING THE STRONG WINDS WERE NOT REDUCING VISIBILITIES THAT
MUCH IN SOUTHEAST MN/NORTHEAST IA PER ASOS/AWOS OBSERVATIONS...DUE
TO THE WET NATURE OF THE SNOW. HOWEVER...CALLS TO COUNTY SHERIFFS
IN THE SAME AREA WERE REPORTING WHITEOUTS WITH SOME ROADS
CLOSED...SUGGESTING ASOS/AWOS OBSERVATIONS WERE NOT FULLY
REPRESENTATIVE. IN ADDITION...POWER OUTAGES WERE A MAJOR ISSUE
WITH THE WEIGHT OF THE WET SNOW ON TREES/POWER LINES AND WINDS.
NOW THE WINDS HAVE ADVECTED COLDER AIR INTO THE FORECAST AREA AS
NOTED BY TEMPERATURES IN THE TEENS TO LOW 20S. THE COLDER AIR HAS
ALLOWED THE SNOW TO BECOME DRIER...MORE ABLE TO BLOW.
THE NEARLY VERTICALLY STACKED LOW WILL CONTINUE LIFTING
NORTHEASTWARD OVER THE NEXT 24 HOURS...REACHING NORTHERN ONTARIO
THIS EVENING. AS THE LOW PULLS AWAY...THE WINDS WILL GRADUALLY
RELAX...DROPPING FROM 20 TO 35 MPH WITH HIGHER GUSTS DURING THE
MORNING TO 10 TO 25 MPH BY 00Z. FURTHER DIMINISHING OF THE WINDS ARE
EXPECTED TONIGHT. IN TERMS OF THE COLD CONVEYOR BELT OF SNOW...GOOD
AGREEMENT EXISTS THAT THE SNOW SHOULD EXIT MOST LOCATIONS WEST OF
THE MISSISSIPPI RIVER BY 12Z...LOCATIONS SOUTHWEST OF I-94 BY
18Z...AND THE CHIMNEY AREA BY 00Z. MUCH OF THE SNOW SHOULD BE
LIGHT WITH THE SYSTEM OCCLUDED AND MOVING AWAY. JUXTAPOSITION OF
THE WINDS AND SNOW SUGGESTS CONTINUATION OF HAZARDS OVER THE
NORTHWEST HALF OF THE FORECAST AREA. CONTEMPLATED RIGHT NOW
CANCELING SOME OF THE WINTER WEATHER ADVISORY...BUT HAVE KEPT IT
GOING FOR NOW DUE TO LIGHT SNOW GOING THROUGH AND STRONG WINDS
ALLOWING THAT TO BLOW AROUND...WINDS AT ADVISORY LEVEL...AND COLD
AIR ALLOWING RECENT WATER TO FREEZE.
WE SHOULD ALSO SEE SOME CLEARING TODAY SOUTHWEST TO NORTHEAST AS
DRIER/SUBSIDENT AIR OVER THE PLAINS ADVECTS IN BEHIND THE SYSTEM.
THIS CLEARING IS WELL EVIDENT OVER WESTERN IOWA AND FAR SOUTHWEST MN
CURRENTLY. THE DRIER AIR HOLDS INTO TONIGHT...SO ALTHOUGH SOME
SHORTWAVES ROTATING AROUND THE UPPER LOW ARE PROGGED TO COME ACROSS
THE FORECAST AREA...NO PRECIPITATION OR EVEN CLOUD IMPACTS ARE
EXPECTED FROM THEM.
925MB TEMPERATURES OF -8 TO -12C TODAY WILL RESULT IN MUCH COOLER
HIGHS TODAY COMPARED TO YESTERDAY...AS MUCH AS 15 TO 20 DEGREES
COLDER. 925MB TEMPS COOL EVEN MORE TONIGHT...TO -10 TO -16C BY 12Z
SATURDAY...COLDEST NORTH. HAVING MOSTLY CLEAR SKIES...COOLING TEMPS
AND FRESH SNOW IS CONCERNING FOR TEMPERATURES TO TANK...BUT MIXING
OF THE WINDS SHOULD HELP KEEP MOST LOCATIONS ABOVE 0F. THE LONE
EXCEPTION TO GO BELOW ZERO COULD BE UP IN TAYLOR COUNTY WHERE THE
COLDEST AIR IS FLOWING IN. COMBINATION OF THE WINDS AND FALLING
TEMPS BRINGS WIND CHILLS CLOSE BUT NOT TO -20F...WHEN WE WOULD ISSUE
WIND CHILL ADVISORIES.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 214 AM CST FRI FEB 21 2014
MUCH OF THE LONG TERM PERIOD IS DOMINATED BY A STUCK UPPER LEVEL
PATTERN...RESULTING FROM AN OMEGA BLOCK THAT DEVELOPS AND
STRENGTHENS FROM ALONG THE U.S. WEST COAST INTO FAR WESTERN CANADA.
THE STRENGTHENING OMEGA BLOCK CORRELATES WELL WITH A STRATOSPHERIC
WARMING EVENT TAKING PLACE OVER THE ALEUTIANS THE NEXT FEW DAYS.
THIS OMEGA BLOCK WILL ALLOW A SERIES OF SHORTWAVE TROUGHS DROPPING
OUT OF THE ARCTIC TO COME THROUGH THE FORECAST AREA. IN THE WAKE OF
EACH TROUGH...A SURGE OF COLDER AIR WITH ARCTIC HIGH PRESSURE WILL
FOLLOW. GIVEN THE ARCTIC NATURE OF THE SHORTWAVES...MOISTURE AND
PRECIPITATION IS GOING TO BE HARD TO COME BY. THE ONLY REAL CHANCE
IT LOOKS LIKE FOR SNOW WILL COME MONDAY INTO MONDAY NIGHT WITH A
SHORTWAVE TROUGH DROPPING THROUGH THEN. STILL...AT THIS POINT...IT
DOES NOT APPEAR TO BE A BIG SNOW PRODUCER. HIGHEST CHANCES ARE
SITUATED OVER THE SOUTHWEST HALF OF THE FORECAST AREA.
NOW THE MAIN IMPACT ISSUE...THE COLD...WHICH HAS BEEN CONSISTENTLY
FORECASTED FROM THE ECMWF/GFS AND CFS. HAVING ARCTIC COLD FLOW INTO
THE FORECAST AREA ALSO CORRELATES WELL WITH THE AFOREMENTIONED
STRATOSPHERIC WARMING OVER THE ALEUTIANS.
THE WEEKEND...925MB TEMPS ARE NOT FORECAST TO CHANGE MUCH THROUGH
THE WEEKEND FROM THE -10 TO -16C PROGGED AT 12Z SATURDAY. THIS
SHOULD RESULT IN HIGHS SIMILAR FOR BOTH DAYS...RANGING FROM THE LOW
TEENS TO LOW 20S. TEMPERATURES SATURDAY NIGHT COULD FALL QUITE A BIT
WITH A WEAKER PRESSURE GRADIENT. TYPICAL COLD SPOTS WILL LIKELY
DECOUPLE...ALLOWING THEM TO APPROACH 10 BELOW. WIND CHILLS MAY FLIRT
WITH ADVISORY CRITERIA AS WELL SUNDAY MORNING.
NEXT WEEK...BEHIND THE MONDAY SHORTWAVE TROUGH...925MB TEMPS FALL TO
-18 TO -22C BY 12Z TUESDAY PER 21.00Z ECMWF/GFS. A COLDER SURGE
COMES IN TUESDAY NIGHT BEHIND ANOTHER SHORTWAVE TROUGH...WITH THOSE
925MB TEMPS DOWN TO -22 TO -26C AT 12Z WEDNESDAY. MORE IMPORTANTLY
WITH THIS COLD SURGE IS STRONGER 925MB WINDS OF 25-35 KTS...WHICH
RESULTS IN WIND CHILL ADVISORY NEED. THE FINAL AND COLDEST OF THE
COLD COMES WEDNESDAY NIGHT INTO THURSDAY. 925MB TEMPS ARE SIMILAR TO
THE TUESDAY NIGHT SURGE...BUT 850MB TEMPS APPROACH -30C IN TAYLOR
COUNTY...SUGGESTING A DEEPER COLDER AIRMASS. AND LIKE TUESDAY
NIGHT...PLENTY OF WIND IS FORECAST...SO WIND CHILL ADVISORY HAZARDS
LOOK LIKELY. IN FACT...LOWS THEMSELVES SHOULD BE IN THE SINGLE
DIGITS TO TEENS BELOW ZERO TUESDAY NIGHT THROUGH THURSDAY NIGHT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1150 AM CST FRI FEB 21 2014
STRONG WEST WINDS AT 20 TO 30 WITH GUSTS TO 35 WILL PERSIST THROUGH
MUCH OF THE AFTERNOON HOURS...PER LATEST RAP SOUNDINGS. KRST/KLSE ON
CLEARING EDGE OF THE CLOUDS...VIA SFC OBS AND SATELLITE IMAGERY. OBS
MAY POINT TO SOME CIGS FROM BLOWING SNOW. GOING TO KEEP VSBY
RESTRICTIONS AT KRST THROUGH THE AFTERNOON. VFR CONDITIONS SHOULD BE
THE RULE TONIGHT INTO SATURDAY WITH SKC SKIES AND WINDS TAPERING
OFF INTO THE 10 TO 15 KT RANGE.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR WIZ017-
029-032>034.
WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR
WIZ041>044-053>055-061.
MN...WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR MNZ079-
086>088-094-095.
WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR MNZ096.
IA...WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR
IAZ008>010-018-019-029.
WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR IAZ011-
030.
&&
$$
UPDATED......RIECK
SHORT TERM...AJ
LONG TERM....AJ
AVIATION.....RIECK
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
540 AM CST FRI FEB 21 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 214 AM CST FRI FEB 21 2014
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED NORTHWEST FLOW FROM ALASKA DOWN INTO THE MID-MISSISSIPPI
RIVER VALLEY AND A DEEP UPPER LOW OVER NORTHERN WI. UNDERNEATH THE
UPPER LOW WAS A 978 MB SURFACE LOW NEAR RHINELANDER. A VERY TIGHT
PRESSURE GRADIENT SOUTHWEST OF THE LOW WAS SUPPORTING SURFACE WINDS
OF 25 TO 35 MPH WITH GUSTS UP TO 55 MPH. THE COLD CONVEYOR BELT
WRAPPING AROUND THE NEARLY VERTICALLY STACKED LOW WAS STILL BRINGING
SNOW TO THE FORECAST AREA...HEAVIEST OVER NORTH CENTRAL WI. EARLIER
LAST EVENING THE STRONG WINDS WERE NOT REDUCING VISIBILITIES THAT
MUCH IN SOUTHEAST MN/NORTHEAST IA PER ASOS/AWOS OBSERVATIONS...DUE
TO THE WET NATURE OF THE SNOW. HOWEVER...CALLS TO COUNTY SHERIFFS
IN THE SAME AREA WERE REPORTING WHITEOUTS WITH SOME ROADS
CLOSED...SUGGESTING ASOS/AWOS OBSERVATIONS WERE NOT FULLY
REPRESENTATIVE. IN ADDITION...POWER OUTAGES WERE A MAJOR ISSUE
WITH THE WEIGHT OF THE WET SNOW ON TREES/POWER LINES AND WINDS.
NOW THE WINDS HAVE ADVECTED COLDER AIR INTO THE FORECAST AREA AS
NOTED BY TEMPERATURES IN THE TEENS TO LOW 20S. THE COLDER AIR HAS
ALLOWED THE SNOW TO BECOME DRIER...MORE ABLE TO BLOW.
THE NEARLY VERTICALLY STACKED LOW WILL CONTINUE LIFTING
NORTHEASTWARD OVER THE NEXT 24 HOURS...REACHING NORTHERN ONTARIO
THIS EVENING. AS THE LOW PULLS AWAY...THE WINDS WILL GRADUALLY
RELAX...DROPPING FROM 20 TO 35 MPH WITH HIGHER GUSTS DURING THE
MORNING TO 10 TO 25 MPH BY 00Z. FURTHER DIMINISHING OF THE WINDS ARE
EXPECTED TONIGHT. IN TERMS OF THE COLD CONVEYOR BELT OF SNOW...GOOD
AGREEMENT EXISTS THAT THE SNOW SHOULD EXIT MOST LOCATIONS WEST OF
THE MISSISSIPPI RIVER BY 12Z...LOCATIONS SOUTHWEST OF I-94 BY
18Z...AND THE CHIMNEY AREA BY 00Z. MUCH OF THE SNOW SHOULD BE
LIGHT WITH THE SYSTEM OCCLUDED AND MOVING AWAY. JUXTAPOSITION OF
THE WINDS AND SNOW SUGGESTS CONTINUATION OF HAZARDS OVER THE
NORTHWEST HALF OF THE FORECAST AREA. CONTEMPLATED RIGHT NOW
CANCELING SOME OF THE WINTER WEATHER ADVISORY...BUT HAVE KEPT IT
GOING FOR NOW DUE TO LIGHT SNOW GOING THROUGH AND STRONG WINDS
ALLOWING THAT TO BLOW AROUND...WINDS AT ADVISORY LEVEL...AND COLD
AIR ALLOWING RECENT WATER TO FREEZE.
WE SHOULD ALSO SEE SOME CLEARING TODAY SOUTHWEST TO NORTHEAST AS
DRIER/SUBSIDENT AIR OVER THE PLAINS ADVECTS IN BEHIND THE SYSTEM.
THIS CLEARING IS WELL EVIDENT OVER WESTERN IOWA AND FAR SOUTHWEST MN
CURRENTLY. THE DRIER AIR HOLDS INTO TONIGHT...SO ALTHOUGH SOME
SHORTWAVES ROTATING AROUND THE UPPER LOW ARE PROGGED TO COME ACROSS
THE FORECAST AREA...NO PRECIPITATION OR EVEN CLOUD IMPACTS ARE
EXPECTED FROM THEM.
925MB TEMPERATURES OF -8 TO -12C TODAY WILL RESULT IN MUCH COOLER
HIGHS TODAY COMPARED TO YESTERDAY...AS MUCH AS 15 TO 20 DEGREES
COLDER. 925MB TEMPS COOL EVEN MORE TONIGHT...TO -10 TO -16C BY 12Z
SATURDAY...COLDEST NORTH. HAVING MOSTLY CLEAR SKIES...COOLING TEMPS
AND FRESH SNOW IS CONCERNING FOR TEMPERATURES TO TANK...BUT MIXING
OF THE WINDS SHOULD HELP KEEP MOST LOCATIONS ABOVE 0F. THE LONE
EXCEPTION TO GO BELOW ZERO COULD BE UP IN TAYLOR COUNTY WHERE THE
COLDEST AIR IS FLOWING IN. COMBINATION OF THE WINDS AND FALLING
TEMPS BRINGS WIND CHILLS CLOSE BUT NOT TO -20F...WHEN WE WOULD ISSUE
WIND CHILL ADVISORIES.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 214 AM CST FRI FEB 21 2014
MUCH OF THE LONG TERM PERIOD IS DOMINATED BY A STUCK UPPER LEVEL
PATTERN...RESULTING FROM AN OMEGA BLOCK THAT DEVELOPS AND
STRENGTHENS FROM ALONG THE U.S. WEST COAST INTO FAR WESTERN CANADA.
THE STRENGTHENING OMEGA BLOCK CORRELATES WELL WITH A STRATOSPHERIC
WARMING EVENT TAKING PLACE OVER THE ALEUTIANS THE NEXT FEW DAYS.
THIS OMEGA BLOCK WILL ALLOW A SERIES OF SHORTWAVE TROUGHS DROPPING
OUT OF THE ARCTIC TO COME THROUGH THE FORECAST AREA. IN THE WAKE OF
EACH TROUGH...A SURGE OF COLDER AIR WITH ARCTIC HIGH PRESSURE WILL
FOLLOW. GIVEN THE ARCTIC NATURE OF THE SHORTWAVES...MOISTURE AND
PRECIPITATION IS GOING TO BE HARD TO COME BY. THE ONLY REAL CHANCE
IT LOOKS LIKE FOR SNOW WILL COME MONDAY INTO MONDAY NIGHT WITH A
SHORTWAVE TROUGH DROPPING THROUGH THEN. STILL...AT THIS POINT...IT
DOES NOT APPEAR TO BE A BIG SNOW PRODUCER. HIGHEST CHANCES ARE
SITUATED OVER THE SOUTHWEST HALF OF THE FORECAST AREA.
NOW THE MAIN IMPACT ISSUE...THE COLD...WHICH HAS BEEN CONSISTENTLY
FORECASTED FROM THE ECMWF/GFS AND CFS. HAVING ARCTIC COLD FLOW INTO
THE FORECAST AREA ALSO CORRELATES WELL WITH THE AFOREMENTIONED
STRATOSPHERIC WARMING OVER THE ALEUTIANS.
THE WEEKEND...925MB TEMPS ARE NOT FORECAST TO CHANGE MUCH THROUGH
THE WEEKEND FROM THE -10 TO -16C PROGGED AT 12Z SATURDAY. THIS
SHOULD RESULT IN HIGHS SIMILAR FOR BOTH DAYS...RANGING FROM THE LOW
TEENS TO LOW 20S. TEMPERATURES SATURDAY NIGHT COULD FALL QUITE A BIT
WITH A WEAKER PRESSURE GRADIENT. TYPICAL COLD SPOTS WILL LIKELY
DECOUPLE...ALLOWING THEM TO APPROACH 10 BELOW. WIND CHILLS MAY FLIRT
WITH ADVISORY CRITERIA AS WELL SUNDAY MORNING.
NEXT WEEK...BEHIND THE MONDAY SHORTWAVE TROUGH...925MB TEMPS FALL TO
-18 TO -22C BY 12Z TUESDAY PER 21.00Z ECMWF/GFS. A COLDER SURGE
COMES IN TUESDAY NIGHT BEHIND ANOTHER SHORTWAVE TROUGH...WITH THOSE
925MB TEMPS DOWN TO -22 TO -26C AT 12Z WEDNESDAY. MORE IMPORTANTLY
WITH THIS COLD SURGE IS STRONGER 925MB WINDS OF 25-35 KTS...WHICH
RESULTS IN WIND CHILL ADVISORY NEED. THE FINAL AND COLDEST OF THE
COLD COMES WEDNESDAY NIGHT INTO THURSDAY. 925MB TEMPS ARE SIMILAR TO
THE TUESDAY NIGHT SURGE...BUT 850MB TEMPS APPROACH -30C IN TAYLOR
COUNTY...SUGGESTING A DEEPER COLDER AIRMASS. AND LIKE TUESDAY
NIGHT...PLENTY OF WIND IS FORECAST...SO WIND CHILL ADVISORY HAZARDS
LOOK LIKELY. IN FACT...LOWS THEMSELVES SHOULD BE IN THE SINGLE
DIGITS TO TEENS BELOW ZERO TUESDAY NIGHT THROUGH THURSDAY NIGHT.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 540 AM CST FRI FEB 21 2014
THE STRONG LOW WAS ALREADY IN THE U.P. OF MI EARLY THIS MORNING...
CONTINUING TO MOVE AWAY FROM THE AREA. TAF SITES WERE ALREADY ON THE
EDGE OF THE TRAILING -SN...WHICH LOOKS TO BE OUT OF BOTH TAF SITES
BY 14Z. CIGS HAD GENERALLY COME UP TO THE 1500-2500FT RANGE...WITH
THE DECREASE OF CLOUDS/CLEARING LINE NEAR MANKATO MN TO JUST WEST OF
WATERLOO IA. BROUGHT THIS INTO/THRU THE TAF SITES AROUND 18Z...BUT
IT MAY OCCUR SOONER AT KRST.
BIGGEST REMAINING PROBLEM AT THE TAF SITES IS THE STRONG GRADIENT
WINDS BEHIND THE LOW WHICH WILL PERSIST ACROSS THE AREA TODAY.
THESE WINDS TO PRODUCE IFR/MVFR VSBYS IN BLSN AT SITES LIKE KRST
THRU MUCH OF THE MORNING. VSBYS AT KRST SHOULD GRADUALLY IMPROVE TO
MVFR BY LATE MORNING BUT WITH WINDS EXPECTED TO GUST 30-35KTS MVFR
VSBYS LOOK TO LINGER AT KRST MUCH OF THE AFTERNOON. WINDS DIMINISH
TO 15-20KTS THIS EVENING...WITH VFR CONDITIONS TONIGHT INTO SAT
MORNING AS COLDER/DRIER ARCTIC HIGH PRESSURE GRADUALLY BUILDS IN.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER WEATHER ADVISORY UNTIL NOON CST TODAY FOR WIZ041>044-
053>055-061.
WINTER STORM WARNING UNTIL NOON CST TODAY FOR WIZ017-029-032>034.
MN...BLIZZARD WARNING UNTIL NOON CST TODAY FOR MNZ079-086-087-094-095.
WINTER WEATHER ADVISORY UNTIL NOON CST TODAY FOR MNZ096.
WINTER STORM WARNING UNTIL NOON CST TODAY FOR MNZ088.
IA...BLIZZARD WARNING UNTIL NOON CST TODAY FOR IAZ008>010-018-019-029.
WINTER WEATHER ADVISORY UNTIL NOON CST TODAY FOR IAZ011-030.
&&
$$
SHORT TERM...AJ
LONG TERM....AJ
AVIATION.....RRS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
214 AM CST FRI FEB 21 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 214 AM CST FRI FEB 21 2014
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED NORTHWEST FLOW FROM ALASKA DOWN INTO THE MID-MISSISSIPPI
RIVER VALLEY AND A DEEP UPPER LOW OVER NORTHERN WI. UNDERNEATH THE
UPPER LOW WAS A 978 MB SURFACE LOW NEAR RHINELANDER. A VERY TIGHT
PRESSURE GRADIENT SOUTHWEST OF THE LOW WAS SUPPORTING SURFACE WINDS
OF 25 TO 35 MPH WITH GUSTS UP TO 55 MPH. THE COLD CONVEYOR BELT
WRAPPING AROUND THE NEARLY VERTICALLY STACKED LOW WAS STILL BRINGING
SNOW TO THE FORECAST AREA...HEAVIEST OVER NORTH CENTRAL WI. EARLIER
LAST EVENING THE STRONG WINDS WERE NOT REDUCING VISIBILITIES THAT
MUCH IN SOUTHEAST MN/NORTHEAST IA PER ASOS/AWOS OBSERVATIONS...DUE
TO THE WET NATURE OF THE SNOW. HOWEVER...CALLS TO COUNTY SHERIFFS
IN THE SAME AREA WERE REPORTING WHITEOUTS WITH SOME ROADS
CLOSED...SUGGESTING ASOS/AWOS OBSERVATIONS WERE NOT FULLY
REPRESENTATIVE. IN ADDITION...POWER OUTAGES WERE A MAJOR ISSUE
WITH THE WEIGHT OF THE WET SNOW ON TREES/POWER LINES AND WINDS.
NOW THE WINDS HAVE ADVECTED COLDER AIR INTO THE FORECAST AREA AS
NOTED BY TEMPERATURES IN THE TEENS TO LOW 20S. THE COLDER AIR HAS
ALLOWED THE SNOW TO BECOME DRIER...MORE ABLE TO BLOW.
THE NEARLY VERTICALLY STACKED LOW WILL CONTINUE LIFTING
NORTHEASTWARD OVER THE NEXT 24 HOURS...REACHING NORTHERN ONTARIO
THIS EVENING. AS THE LOW PULLS AWAY...THE WINDS WILL GRADUALLY
RELAX...DROPPING FROM 20 TO 35 MPH WITH HIGHER GUSTS DURING THE
MORNING TO 10 TO 25 MPH BY 00Z. FURTHER DIMINISHING OF THE WINDS ARE
EXPECTED TONIGHT. IN TERMS OF THE COLD CONVEYOR BELT OF SNOW...GOOD
AGREEMENT EXISTS THAT THE SNOW SHOULD EXIT MOST LOCATIONS WEST OF
THE MISSISSIPPI RIVER BY 12Z...LOCATIONS SOUTHWEST OF I-94 BY
18Z...AND THE CHIMNEY AREA BY 00Z. MUCH OF THE SNOW SHOULD BE
LIGHT WITH THE SYSTEM OCCLUDED AND MOVING AWAY. JUXTAPOSITION OF
THE WINDS AND SNOW SUGGESTS CONTINUATION OF HAZARDS OVER THE
NORTHWEST HALF OF THE FORECAST AREA. CONTEMPLATED RIGHT NOW
CANCELING SOME OF THE WINTER WEATHER ADVISORY...BUT HAVE KEPT IT
GOING FOR NOW DUE TO LIGHT SNOW GOING THROUGH AND STRONG WINDS
ALLOWING THAT TO BLOW AROUND...WINDS AT ADVISORY LEVEL...AND COLD
AIR ALLOWING RECENT WATER TO FREEZE.
WE SHOULD ALSO SEE SOME CLEARING TODAY SOUTHWEST TO NORTHEAST AS
DRIER/SUBSIDENT AIR OVER THE PLAINS ADVECTS IN BEHIND THE SYSTEM.
THIS CLEARING IS WELL EVIDENT OVER WESTERN IOWA AND FAR SOUTHWEST MN
CURRENTLY. THE DRIER AIR HOLDS INTO TONIGHT...SO ALTHOUGH SOME
SHORTWAVES ROTATING AROUND THE UPPER LOW ARE PROGGED TO COME ACROSS
THE FORECAST AREA...NO PRECIPITATION OR EVEN CLOUD IMPACTS ARE
EXPECTED FROM THEM.
925MB TEMPERATURES OF -8 TO -12C TODAY WILL RESULT IN MUCH COOLER
HIGHS TODAY COMPARED TO YESTERDAY...AS MUCH AS 15 TO 20 DEGREES
COLDER. 925MB TEMPS COOL EVEN MORE TONIGHT...TO -10 TO -16C BY 12Z
SATURDAY...COLDEST NORTH. HAVING MOSTLY CLEAR SKIES...COOLING TEMPS
AND FRESH SNOW IS CONCERNING FOR TEMPERATURES TO TANK...BUT MIXING
OF THE WINDS SHOULD HELP KEEP MOST LOCATIONS ABOVE 0F. THE LONE
EXCEPTION TO GO BELOW ZERO COULD BE UP IN TAYLOR COUNTY WHERE THE
COLDEST AIR IS FLOWING IN. COMBINATION OF THE WINDS AND FALLING
TEMPS BRINGS WIND CHILLS CLOSE BUT NOT TO -20F...WHEN WE WOULD ISSUE
WIND CHILL ADVISORIES.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 214 AM CST FRI FEB 21 2014
MUCH OF THE LONG TERM PERIOD IS DOMINATED BY A STUCK UPPER LEVEL
PATTERN...RESULTING FROM AN OMEGA BLOCK THAT DEVELOPS AND
STRENGTHENS FROM ALONG THE U.S. WEST COAST INTO FAR WESTERN CANADA.
THE STRENGTHENING OMEGA BLOCK CORRELATES WELL WITH A STRATOSPHERIC
WARMING EVENT TAKING PLACE OVER THE ALEUTIANS THE NEXT FEW DAYS.
THIS OMEGA BLOCK WILL ALLOW A SERIES OF SHORTWAVE TROUGHS DROPPING
OUT OF THE ARCTIC TO COME THROUGH THE FORECAST AREA. IN THE WAKE OF
EACH TROUGH...A SURGE OF COLDER AIR WITH ARCTIC HIGH PRESSURE WILL
FOLLOW. GIVEN THE ARCTIC NATURE OF THE SHORTWAVES...MOISTURE AND
PRECIPITATION IS GOING TO BE HARD TO COME BY. THE ONLY REAL CHANCE
IT LOOKS LIKE FOR SNOW WILL COME MONDAY INTO MONDAY NIGHT WITH A
SHORTWAVE TROUGH DROPPING THROUGH THEN. STILL...AT THIS POINT...IT
DOES NOT APPEAR TO BE A BIG SNOW PRODUCER. HIGHEST CHANCES ARE
SITUATED OVER THE SOUTHWEST HALF OF THE FORECAST AREA.
NOW THE MAIN IMPACT ISSUE...THE COLD...WHICH HAS BEEN CONSISTENTLY
FORECASTED FROM THE ECMWF/GFS AND CFS. HAVING ARCTIC COLD FLOW INTO
THE FORECAST AREA ALSO CORRELATES WELL WITH THE AFOREMENTIONED
STRATOSPHERIC WARMING OVER THE ALEUTIANS.
THE WEEKEND...925MB TEMPS ARE NOT FORECAST TO CHANGE MUCH THROUGH
THE WEEKEND FROM THE -10 TO -16C PROGGED AT 12Z SATURDAY. THIS
SHOULD RESULT IN HIGHS SIMILAR FOR BOTH DAYS...RANGING FROM THE LOW
TEENS TO LOW 20S. TEMPERATURES SATURDAY NIGHT COULD FALL QUITE A BIT
WITH A WEAKER PRESSURE GRADIENT. TYPICAL COLD SPOTS WILL LIKELY
DECOUPLE...ALLOWING THEM TO APPROACH 10 BELOW. WIND CHILLS MAY FLIRT
WITH ADVISORY CRITERIA AS WELL SUNDAY MORNING.
NEXT WEEK...BEHIND THE MONDAY SHORTWAVE TROUGH...925MB TEMPS FALL TO
-18 TO -22C BY 12Z TUESDAY PER 21.00Z ECMWF/GFS. A COLDER SURGE
COMES IN TUESDAY NIGHT BEHIND ANOTHER SHORTWAVE TROUGH...WITH THOSE
925MB TEMPS DOWN TO -22 TO -26C AT 12Z WEDNESDAY. MORE IMPORTANTLY
WITH THIS COLD SURGE IS STRONGER 925MB WINDS OF 25-35 KTS...WHICH
RESULTS IN WIND CHILL ADVISORY NEED. THE FINAL AND COLDEST OF THE
COLD COMES WEDNESDAY NIGHT INTO THURSDAY. 925MB TEMPS ARE SIMILAR TO
THE TUESDAY NIGHT SURGE...BUT 850MB TEMPS APPROACH -30C IN TAYLOR
COUNTY...SUGGESTING A DEEPER COLDER AIRMASS. AND LIKE TUESDAY
NIGHT...PLENTY OF WIND IS FORECAST...SO WIND CHILL ADVISORY HAZARDS
LOOK LIKELY. IN FACT...LOWS THEMSELVES SHOULD BE IN THE SINGLE
DIGITS TO TEENS BELOW ZERO TUESDAY NIGHT THROUGH THURSDAY NIGHT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1118 PM CST THU FEB 20 2014
THE SNOW WITH THE STORM SYSTEM CONTINUES TO LIFT SLOWLY NORTHEAST
WITH THE RADAR SHOWING THE HEAVIEST SNOW NOW NORTH OF BOTH TAF
SITES. EXPECT THIS TREND TO CONTINUE THROUGH THE NIGHT AS THE LOW
CONTINUES TO PULL OFF TO THE NORTH/NORTHEAST WITH THE SNOW ENDING
BEFORE 12Z AT BOTH SITES. THE STRONGEST WINDS ARE JUST MOVING INTO
THE AREA AND EXPECT THE GUSTS OF 35 TO 40 KNOTS TO CONTINUE FOR
MUCH OF THE NIGHT WITH SOME DECREASE EXPECTED TO OCCUR BY MID
MORNING FRIDAY WITH THE GUSTS COMING DOWN TO 30 TO 35 KNOTS. THESE
WINDS WILL PRODUCE BLOWING SNOW AT KRST WITH IFR VISIBILITIES
EXPECTED UNTIL THE WINDS SETTLE DOWN A LITTLE BIT TO ALLOW THE
VISIBILITY TO COME UP TO MVFR. THE WINDS SHOULD THEN STAY STRONG
ENOUGH TO CONTINUE TO PRODUCE SOME BLOWING SNOW THROUGH MUCH OF
THE DAY. CEILINGS PRIMARILY EXPECTED TO BE MVFR UNTIL THE CLOUDS
SCATTER OUT EARLY FRIDAY AFTERNOON. THE WINDS SHOULD SETTLE DOWN
EVEN MORE LATE FRIDAY AFTERNOON OR EARLY EVENING AS THE GRADIENT
RELAXES SOME MORE AND THE LOW LEVEL INVERSION BEGINS TO DEVELOP.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER WEATHER ADVISORY UNTIL NOON CST TODAY FOR WIZ041>044-
053>055-061.
WINTER STORM WARNING UNTIL NOON CST TODAY FOR WIZ017-029-032>034.
MN...BLIZZARD WARNING UNTIL NOON CST TODAY FOR MNZ079-086-087-094-095.
WINTER WEATHER ADVISORY UNTIL NOON CST TODAY FOR MNZ096.
WINTER STORM WARNING UNTIL NOON CST TODAY FOR MNZ088.
IA...BLIZZARD WARNING UNTIL NOON CST TODAY FOR IAZ008>010-018-019-029.
WINTER WEATHER ADVISORY UNTIL NOON CST TODAY FOR IAZ011-030.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...04
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
355 AM EST Sun Feb 23 2014
...Heavy Rain Possible Across the Florida Panhandle Today...
.Near Term [Through Today]...
The large scale pattern is highlighted by a persistent broad trough
over much of Conus. This leaves nearly zonal flow over NE Gulf
region. However a series of shortwaves will continue to move Ewd
providing increasing clouds and just enough lift that when combined
with surface features will maintain an unsettled weather pattern
today. Mid-High clouds streaming Ewd overnight assocd with lead
shortwave moving Ewd across mid-South will cross NE Gulf region
later today with the forecast area in the right entrance region of
the upper jet. At surface...in response to Ewd moving shortwave...
W-E warm front located across the Nrn Gulf waters Ewd across N/Cntrl
FL overnight will lift Nwd to coast by sunrise then to vcnty of I-10
during the day with light Sly flow in its wake. Upstream cold front
across mid-South around sunrise moves SEWD to Ern TN/N-Cntrl AL/Srn
MS by sundown with WAA and isentropic upglide spreading over our
area. Early radar showing leading edge of moisture approaching wrn
most Panhandle waters.
Patchy to areas of fog initially south of I-10 will accompany rain
and spread E/N thru the day. The combination of upper and lower
features will yield an expansive area of showers with isolated to
sct thunderstorms (highest Panhandle waters) moving SW-NE to reach
our Wrn CWA around sunrise and then progress EWD. Afternoon dew
point will rise from mid 60s coast to upper 50s Nrn tier AL/GA
counties. This depicted well in HRRR and other High Res guidance.
Limited mid-level lapse rates and a relatively cool boundary layer
should limit the potential for any strong storms. Best chance per
CAM would be Panhandle waters. However, with the upper flow parallel
to the warm boundary, main concern is training of cells is possible
with locally heavy rainfall possible especially during the aftn QPF
south of FL border exceeding 1 inch. Will go with 70-30% W-E POP
gradient in morning then 80-40% in the afternoon. Temperatures will
be tricky, depending on the eventual position of the warm front and
the coverage of the rainfall. However, expect warmest temperatures
along and south of I-10 (lower 70s), with lower to mid 60s for much
of SE AL and SW GA.
.Short Term [Tonight Through Tuesday]...
By the time the evening rolls around, the polar jet max will be
racing east and the northern stream trough will dip a bit deeper
into the Southeast. This will act to better stack the frontal
system as surface high pressure presses a cold front into our
region. The surface cold front will merge with Sunday`s warm front
and settle in over north Florida before deep layer zonal flow sets
in and stalls the frontal system once again. As the two fronts
merge, and the system stacks, we`ll likely see a brief uptick in
shower activity along the surface front. Expect rainfall to be
much lighter than Sunday afternoon as the surge of more tropical-
like moisture will have moved east.
On Monday, a southern stream impulse will be lifting north
through the northern Gulf, eventually aligning with the surface
front and pressing the northern stream trough back to the north
out of our area. Exactly where the surface front will be is a bit
uncertain, though the most likely scenario would place the front
along or south of I-10 in north Florida, possibly as far south as
the extreme northern Gulf. Should the surface front be positioned
across north Florida, things could become interesting with respect
to the potential for an isolated strong storm. Due to the limited
tropospheric penetration of the southern stream impulse, the mid-
level cooler/drier air will not be forced as aggressively to the
north. This will effectively steepen mid-level lapse rates across
the Tri-State region with deep layer shear around 60 knots more
than sufficient to support organized updrafts. In the other
corner, slightly warmer mid/upper level temps where the northern
stream trough has retreated a bit, will essentially cap the
potential for deep moist convection, though as the southern stream
impulse moves away, cooler mid/upper temps may slide back south late
in the day, eroding the cap. Bottom line is that there is a very low
potential for strong storms on Monday, though should convection
get going, and should the mid/upper level cap erode the potential
exists for a storm or two to produce gusty winds and possibly some
small hail.
Tuesday, is really the more interesting day as a more potent
southern stream impulse races east out of Texas, through the lower
MS Valley and into the southeast by the late afternoon. Should we
be able to mix out the mid-level cap early enough that the
shortwave is overhead, we`d be able to tap into some rather steep
lapse rates and strong deep layer shear. This could support the
development of more severe level storms with the threat for
damaging winds and hail.
So, through Tuesday expect showers and isolated storms to be
around. Most likely across north Florida Monday, spreading further
inland and increasing in coverage on Tuesday. The potential for a
strong storm or two exists on Monday, with a chance for severe
storms on Tuesday. Uncertainty remains very high regarding strong
to severe storms, as my lengthy discussion above lays out all of
the variables that must align just right. Expect above average
temperatures, in the middle to even upper 70s in some spots, both
Monday and Tuesday.
.Long Term [Tuesday Night Through Sunday]...
A cold front will move through Wednesday with a chance of showers
and thunderstorms. Behind the front high pressure will build in
bringing cooler temperatures and drier air. The models differ with
a series of low pressure systems at the end of the period. The GFS
has precipitation moving across central Florida Friday and a low
developing off the East coast near Georgia and South Carolina
followed by another low forming over Texas. The Euro has a Gulf
low forming near the Texas/Louisiana border Friday night then
moving across north Florida Saturday.
&&
.Aviation...
[Through 06Z Monday]
MVFR CIGS should develop during the predawn hours or shortly after
sunrise at ECP, TLH and VLD, lowering to IFR CIGS during
the morning hours. There will be a chance of MVFR CIGS at DHN and
ABY during the day tomorrow as well. With a prolonged rain event
any improvement in evening VSBYS/CIGS will begin to again lower
after 02z and winds die off. Rain and isold thunderstorms will move
in from the west during the morning. Heaviest rain and thunderstorm
activity will likely be focused in Florida Panhandle particularly at
ECP, but also possibly affecting TLH. Main impact would be through
reduced visibility due to very heavy rain. Thunderstorms may also
linger at ECP or TLH south of warm front for several hours in the
afternoon.
&&
.Marine...
Generally low winds and seas will prevail through mid-week until a
cold front passes through the northern Gulf increasing winds to
advisory levels temporarily on Wednesday. Low winds and seas will
return to finish out the week.
&&
.Fire Weather...
With increased rain chances thru tonight, no red flag conditions are
expected and none is forecast through mid-next week.
&&
.Hydrology...
There is a potential for heavy rainfall this afternoon with the
heaviest rain likely confined to north Florida, especially along
and west of the Apalachicola River. Widespread average totals will
be around 1-2 inches with isolated spots possibly receiving up to
3 to 5 inches. Flash flooding will likely not be a concern as
these basins should be able to accommodate the expected rainfall
amounts. In areas where heavy rainfall is expected, rivers may
reach minor flood stage Monday or Tuesday. The Apalachicola at
Blountstown is forecast to reach minor flood stage Sunday morning.
For the latest hydrology information, please monitor:
www.water.weather.gov/ahps2/index.php?wfo=tae
&&
.Preliminary Point Temps/PoPs...
Tallahassee 69 59 75 54 74 / 70 70 40 10 50
Panama City 67 60 70 57 69 / 80 70 40 20 50
Dothan 64 56 73 51 71 / 70 50 10 10 50
Albany 65 55 73 49 72 / 70 50 10 10 40
Valdosta 70 58 75 53 73 / 70 70 40 10 40
Cross City 73 60 75 57 75 / 50 70 40 10 50
Apalachicola 67 61 69 58 67 / 60 70 40 10 50
&&
.TAE Watches/Warnings/Advisories...
FL...None.
GA...None.
AL...None.
GM...None.
&&
$$
NEAR TERM...BLOCK
SHORT TERM...HARRIGAN
LONG TERM...WESTON
AVIATION...BLOCK
MARINE...HARRIGAN
FIRE WEATHER...BLOCK
HYDROLOGY...HARRIGAN/WESTON
Area Forecast Discussion
National Weather Service Lincoln IL
330 AM CST Sun Feb 23 2014
.DISCUSSION...
ISSUED 330 AM CST Sun Feb 23 2014
SHORT TERM...Today through Wednesday night
Surface cold front has pressed south of the Ohio River into nw AR
while 1042 mb arctic high pressure over Alberta was nosing into
the central and northern plains. Colder air easing south into
central IL early this morning with temps slipping through the 20s
over central IL and low to mid 30s in southeast IL. Temps as cold
as 19F at Galesburg and Lacon. Frontogenetic forecasing close to
850 mb boundary near I-70 had band of light snow that diminished
east into central IN past few hours with dusting to as much as 1
inch between I-72 and I-70. Will carry just slight chance of light
snow this morning over southeast IL per HRRR model run. Radar
mosaic shows light pcpn returns and mainly virga over northern MO
into nw counties. RUC & HRRR keeps most of this very light snow
west of central IL this morning but could be a few flurries this
morning into central IL. Clouds to decrease from the north during
the afternoon and linger longest in southeast IL. Much colder
highs today range from mid 20s from Peoria and Bloomington north
to 35-40F over southeast IL with Lawrenceville near 40F.
Arctic high pressure noses into the mid MS river valley tonight
and brings fair skies and cold lows of 5-10F from Lincoln north
and mid to upper teens in southeast IL. Clouds increase Monday
morning ahead of northern stream clipper system which digs into
the Midwest Monday night. Slowed down chances of light snow Monday
afternoon as central IL appear dry through sunset Monday with best
chances of light snow arriving Monday night northern half of CWA.
Generally less than 1 inch of snow with northern IL having as much
as 1-2 inches of snow possible. Highs Monday again in mid 20s
north and mid to upper 30s in southeast IL. Lows Monday night in
the teens central IL and lower 20s southeast IL. Chances of light
snow ne of central IL by Tuesday morning. Highs Tue range from
lower 20s northern areas to mid 30s in southeast IL.
Core of arctic high pressure settles into MO by 18Z/noon Wed and
brings even colder air into the region during middle of the week.
Lows overnight Tue night into early Wed morning could reach zero
to 5 below nw of IL river with single digit lows over much of
central IL and far southeast IL around 10F. Highs Wed in the mid
teens ne to lower 20s sw and se areas. Lows Wed night again in the
single digits over northern half of CWA and lower teens south.
LONG TERM...Thursday through Saturday night
Temps modify slightly during end of week but still average below
normal through next weekend. The 8-14 day outlook for Mar 2-8 has
60-70% chance of below normal temperatures and 40% chance of above
normal precipitation, which has been the normal for this winter.
Generally dry and cold conditions expected late this week into
next weekend. Though ECMWF and GEM models show some light qpf
Friday while heavier qpf passes south of IL Friday. GFS model is
dry over IL on Friday. Stayed close to ALLblend pops late this
week and into the weekend which is dry.
07
&&
.AVIATION...
ISSUED 1140 PM CST Sat Feb 22 2014
Persistent band of snow has now shifted southeast of the KILX
terminals, so VFR conditions are expected through the entire 06z
TAF period. Winds will remain northerly at less than 10kt tonight
through Sunday afternoon before backing to northwesterly by
evening. Only mid/upper-level clouds are expected as weak
disturbances embedded within broad northwesterly flow aloft pass
through the area over the next 24 hours.
Barnes
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
214 AM CST SUN FEB 23 2014
.DISCUSSION...
213 AM CST
TODAY...
BROAD SFC RIDGE STRETCHES FROM THE NORTHERN PLAINS SOUTHEAST
THROUGH THE WESTERN OHIO VALLEY. THIS HAS RESULTED IN A LIGHT
NORTHWEST FLOW ACROSS NORTHERN IL/NORTHWEST IN EARLY THIS MORNING.
BAROCLINIC ZONE REMAINS ORIENTED FROM CENTRAL MO STRETCHING
NORTHEAST THROUGH CENTRAL IL/IN AND DRIFTING SOUTHEAST. IR IMAGERY
SHOWS THE AREA OF CLOUDS WELL...ASSOCIATED WITH THIS BAND OF
PRECIP. THEN JUST WEST OF THIS FEATURE WAS YET ANOTHER WEAK MID-
LVL WAVE THAT HAD ANOTHER AREA OF MID/UPR LVL MOISTURE ASSOCIATED
WITH IT AND WAS SLIDING EAST...BEING STEERED BY THE SEMI-ZONAL
FLOW IN THE MID-LVLS.
TEMPS THIS MORNING WILL HOVER AROUND THE TEENS FOR THE BULK OF THE
FORECAST AREA...PERHAPS HOLDING IN UPR TEENS/LOW 20S FOR THE
SOUTHERN CWFA. OTHERWISE FOR TODAY HIGH PRESSURE WILL PUSH THIS AREA
OF CLOUDS THIS MORNING TO THE SOUTH...AND ALLOW FOR A DRY DAY. SKIES
WILL EVENTUALLY BECOME P-CLOUDY BY MIDDAY...WITH HIGHS WARMING
MAINLY INTO THE 20S. CLOSER TO 30 FOR THE FAR SOUTHERN CWFA.
THEN FOR TONIGHT...HIGH PRESSURE WILL CONTINUE TO HOLD ACROSS THE
FORECAST AREA AND LIMIT CLOUD COVER. JUST NORTH OF THE AREA
THOUGH...AND CLOSER TO A STRONGER MID-LVL VORT WILL BE THICKER CLOUD
COVER. WINDS WILL GENERALLY REMAIN LIGHT FROM THE NORTHWEST...WHICH
COUPLED WITH 850MB TEMPS HOVERING ARND -10 TO -12 DEG C SHOULD LIMIT
HOW COOL TEMPS RADIATE OVERNIGHT. SO HAVE ONLY NUDGED TEMPS DOWN A
LITTLE...GENERALLY IN THE SINGLE DIGITS ABOVE ZERO. COULD SEE SOME
OF THE TRADITIONALLY COOLER LOCATIONS DIP TO ARND ZERO BY DAYBREAK
MON.
CONFIDENCE...HIGH.
MONDAY THROUGH TUESDAY...
500MB TROUGH AXIS OVER THE GREAT LAKES REGION PUSHES EAST...WITH AN
AREA OF WEAK RIDGING ARRIVING MIDDAY MON OVER THE FORECAST AREA.
HOWEVER GIVEN THE SEMI-ZONAL FLOW...WHICH IS GENERALLY A MORE
PROGRESSIVE SETUP...THE NEXT WAVE CONTINUES TO BE PROGGED FOR
ARRIVAL MON LATE AFTN/EVE. LATEST FORECAST GUIDANCE HAS CONTINUED TO
SUGGEST THE MID-LVL HEIGHT RISES MAY BE A LITTLE SLOWER TO DEPART
THE REGION...WHICH WOULD LIKELY HAVE AN INFLUENCE ON THE WEAK WAVE
ARRIVING POSSIBLY LATER. THE MAIN TIMING DOES APPEAR TO BE
CONSISTENT WITH JUST AFT 00Z TUE...AND GIVEN THE PREV-DISCUSSED
PROGRESSIVE FLOW...SKIES WILL THICKEN RATHER QUICKLY AND CIGS WILL
LOWER WITH EASE. LOCAL MODEL INDICATES A SLIGHTLY LATER ARRIVAL AND
CLOSER TO 6Z TUE...BUT ALSO IS INDICATING THE WAVE WILL BE WEAKENING
UPON ARRIVAL. CONFIDENCE ON THIS WAVE WEAKENING AS IT ARRIVES IS
VERY LOW...GIVEN THE DECENT MID-LVL FORCING ASSOCIATED. TEMPS
CONTINUE TO BE COOL ENOUGH TO SUPPORT LGT SNOW FOR THE AREA...AND
EXPECT SLR ARND 15:1 TO 18:1. THIS WILL LIKELY PRODUCE A QUICK 1 TO
2 INCHES OF SNOWFALL ACROSS MOST OF THE CWFA. BY 12-15Z TUE...THE
BULK OF THE WAVE/SNOW WILL BE PUSHING EAST AND COMING TO AN END.
THEN FOR TUE...500MB TROUGH AXIS ARRIVES AS AN ARCTIC AIRMASS
CONTINUES TO PUSH SOUTH FROM CANADA TOWARDS THE UPPER MIDWEST TUE
AFTN. CURRENTLY EXPECT HIGHS TUE TO HOLD IN THE TEENS/LOW
20S...HOWEVER BY TUE NGT THE BOUNDARY WILL BE PUSHING ACROSS THE
FORECAST AREA AND TEMPS WILL BE DROPPING TO A FEW DEGREES BELOW
ZERO.
CONFIDENCE...HIGH.
CONFIDENCE IN SNOW ACCUMS MON EVE/OVERNIGHT...HIGH.
WEDNESDAY THROUGH SUNDAY...
ENSEMBLES AND OPERATIONAL SOLUTIONS HAVE CONTINUED TO BE IN GOOD
AGREEMENT WITH THE ARRIVAL OF YET ANOTHER ARCTIC AIRMASS. BY WED THE
500MB TROUGH AXIS WILL BE OVERHEAD. CURRENT PROGS INDICATE TEMPS IN
MID-LVLS WILL HOVER ARND -20 TO -25 DEG C. WHEN APPLYING THIS
TOWARDS LOCAL CLIMATE WHICH LIKELY YIELD HIGH TEMPS WED IN THE
SINGLE DIGITS ABOVE ZERO TO POSSIBLY THE LOW TEENS. SFC RIDGE WILL
BE SLIDING OVER THE AREA AS WELL...WHICH SHOULD LIMIT HOW MUCH LOWER
WIND CHILL VALUES WILL BE WED. THEN FOR WED NGT...FLOW GRADUALLY
TURNS WESTERLY IN THE LLVLS. A WEAK SHORTWAVE IS PROGGED TO CLIP THE
NORTHERN GREAT LAKES REGION...HOWEVER EXPECT GENERALLY DRY WEATHER
FOR THE FORECAST AREA WED/WED NGT.
FOR THE REMAINDER OF THE EXTENDED PERIODS...ENSEMBLES REMAIN IN
DECENT AGREEMENT WITH YET ANOTHER SFC RIDGE SLIDING SOUTHEAST FROM
CENTRAL CANADA TOWARDS THE PLAINS AND STRETCHING EAST TO THE WESTERN
GREAT LAKES THUR. THIS SHOULD HELP TO MAINTAIN UNSEASONABLY COLD
CONDS FOR THE FORECAST AREA...WITH TEMPS STRUGGLING TO WARM BEYOND
THE LOW/MID TEENS THUR AFTN.
STRONG VORTEX BEGINS TO LIFT NORTHEAST THUR NGT/FRI...WITH SOME
MODERATION TO TEMPS POISED FOR THE END OF THE WEEK INTO THE FIRST
HALF OF NEXT WEEKEND. ALTHOUGH THIS IS RELATIVE...AS TEMPS WILL
CONTINUE TO BE UNSEASONABLY COOL IN THE TEENS/LOW 20S. GUIDANCE IS
SUGGESTING THE SOUTHERN STREAM WILL BECOME ACTIVE YET AGAIN IN THE
LATER PERIODS...AND INDICATES THE PRECIP WILL REMAIN SOUTH OF THE
CWFA. ALTHOUGH COULD SEE SOME ADJUSTMENTS TO THE PLACEMENT OF EACH
SOUTHERN STREAM WAVE.
CONFIDENCE...MEDIUM/HIGH.
BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* NONE
//DISCUSSION...UPDATED 06Z...
QUIET WEATHER DAY ON TAP THIS TAF PERIOD WITH VFR CONDITIONS AND WNW
WINDS THROUGHOUT THE PERIOD. A FEW GUSTS INTO THE HIGH TEENS TO
AROUND 20 KT ARE POSSIBLE DURING THE AFTERNOON AND EVENING
SUNDAY...THEN SHOULD TAPER MID TO LATE IN THE EVENING. THE NEXT
CHANCE FOR WEATHER IMPACTS APPEARS TO BE MONDAY NIGHT INTO TUESDAY
WHEN SNOW WILL MOVE ACROSS THE AREA.
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* HIGH
BMD
//OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z...
MONDAY...VFR LIKELY DURING DAYTIME THEN LIGHT SNOW BECOMING
LIKELY MONDAY NIGHT WITH MVFR LIKELY...IFR POSSIBLE.
TUESDAY...CHANCE OF LIGHT SNOW EARLY AM. THEN VFR LIKELY.
WEDNESDAY THROUGH FRIDAY...VFR LIKELY.
RC
&&
.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.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
National Weather Service Lincoln IL
1140 PM CST Sat Feb 22 2014
.DISCUSSION...
ISSUED 636 PM CST Sat Feb 22 2014
Made a few quick updates to the forecast to better reflect current
trends, mainly to tighten the POP gradient across central Illinois.
Radar continues to indicate the narrow band of precipitation
remaining focused along a Jacksonville to Danville line. Latest
run of the HRRR shows very little movement of the band until 04z
when it slowly sinks southeastward. As a result, have increased
POPs to categorical within the band itself and have removed all
mention of POPs further north in the Peoria area and further south
from Effingham southward. With surface temps in the middle to
upper 30s initially, precip has started as rain at most sites, but
is quickly transitioning to wet snow as evaporative cooling takes
place within the surface-based layer. Based on gradual eastward
shift of precip area and current temps above freezing, think snow
accumulations will remain light. 1 to 2 inches still look reasonable
across the E/NE KILX CWA, mainly from Decatur northeastward
through Champaign to Danville, with little or no accumulation
elsewhere around the area. Zone update has already been issued.
Barnes
&&
.AVIATION...
ISSUED 1140 PM CST Sat Feb 22 2014
Persistent band of snow has now shifted southeast of the KILX
terminals, so VFR conditions are expected through the entire 06z
TAF period. Winds will remain northerly at less than 10kt tonight
through Sunday afternoon before backing to northwesterly by
evening. Only mid/upper-level clouds are expected as weak
disturbances embedded within broad northwesterly flow aloft pass
through the area over the next 24 hours.
Barnes
&&
.PREV 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.
Barnes
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
1230 AM EST SUN FEB 23 2014
.SYNOPSIS...
ISSUED AT 608 PM EST SAT FEB 22 2014
SNOW WILL BE POSSIBLE OVERNIGHT MAINLY NEAR AND SOUTH OF HIGHWAY
24. ANY MIXED PRECIPITATION WILL QUICKLY CHANGE OVER TO ALL SNOW
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 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1230 AM EST SUN FEB 23 2014
ACTIVE FRONTAL BOUNDARY REMAINS JUST SOUTH OF KFWA AND LITTLE
NORTHWARD MOVEMENT IS EXPECTED THROUGH THE REST OF THE NIGHT. IN
FACT...RECENT RADAR RETURNS ARE BEGINNING TO WEAKEN AND EXPECT
SNOWFALL TO CONTINUE WINDING DOWN OVER THE NEXT FEW HOURS AS
PARENT JET FORCING LIFTS NORTHEAST. THEREFORE EXPECT VFR
CONDITIONS TO CONTINUE THROUGH MUCH OF THE PERIOD AS CANADIAN
RIDGE AXIS BUILDS INTO THE OHIO VALLEY. OUTSIDE CHANCE OF A FEW
STRATOCU DURING THE DAY BUT DRY LOW LEVELS WILL BE DIFFICULT TO
OVERCOME AND MAY BE ABLE TO REMOVE MENTION ALTOGETHER WITH THE 12Z
ISSUANCE.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SYNOPSIS...KG
SHORT TERM...LASHLEY
LONG TERM...SKIPPER
AVIATION...AGD
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.NORTHERNIN.GOV
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
338 AM EST SUN FEB 23 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...(MONDAY THROUGH SATURDAY)
ISSUED AT 338 AM EST SUN FEB 23 2014
BIGGEST ISSUES IN THE LONG TERM ARE WITH THE RETURN OF EXTREMELY
COLD AIR AND LIGHT-MODERATE LES.
FOR LES CONSIDERATIONS...SOME BREAK UP OF LAKE SUPERIOR ICE HAS
OCCURRED OVER THE LAST COUPLE OF DAYS WITH THE STRONG WLY WINDS.
THIS WILL ALLOW FOR INCREASED LES ACTIVITY OVER THE NEXT WEEK.
MON WILL SEE DIMINISHING NW FLOW LES POPS AS A RIDGE PASSES OVERHEAD
AND 850MB TEMPS DECREASE FROM THE MID 20S TO MID TEENS BELOW ZERO.
WILL SEE SEVERAL PIECES OF ENERGY MOVING THROUGH THE REGION OVER THE
NEXT WEEK...EACH ONE PULLING DOWN MORE COLD AIR UNTIL A POLAR LOW
MOVES TO NEAR JAMES BAY BY 12Z THU. 850MB TEMPS AOB -30C MOVE INTO
THE AREA THU NIGHT INTO THE WEEKEND. THIS WILL LEAD TO VERY COLD
TEMPERATURES YET AGAIN. THU LOOKS TO SEE THE COLDEST HIGH TEMPS IN
THE SINGLE DIGITS AND TUE NIGHT SHOULD BE COLDEST. WILL LIKELY BREAK
RECORD LOW HIGH TEMPERATURES THIS WEEK...AND POSSIBLY SOME DAILY
RECORD LOWS.
SOME LIGHT TO MODERATE SNOWFALL IS POSSIBLE AT TIMES THROUGH THE
NEXT WEEK...BUT GREATER OF THE CONFIDENCE VERY UNCERTAIN SO DID NOT
MAKE SIGNIFICANT CHANGES TO THE PREVIOUS FORECAST.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1152 PM EST SAT FEB 22 2014
WITH WEAKENING LOW PRES REMAINING IN THE VCNTY OF FAR NRN
ONTARIO/JAMES BAY AND HIGH PRES CONTINUING TO RIDGE SE FROM THE SRN
CANADIAN ROCKIES TO THE MID MISSISSIPPI VALLEY...BLUSTERY WESTERLY
WINDS WILL CONTINUE FOR MUCH OF THIS FCST PERIOD AT
KIWD/KCMX/KSAW...BUT ESPECIALLY AT THE MORE EXPOSED KCMX SITE. WITH
WINDS GUSTING OVER 30KT AT KCMX OVERNIGHT THRU THE AFTN...BLSN WILL
LIKELY KEEP PREVAILING VIS IN THE LIFR CATEGORY. EXPECT SOME
FLUCTUATION WITH VIS IMPROVING TO IFR FOR BRIEF PERIODS AS WELL AS
FALLING TO VLIFR. WITH THE WESTERLY WINDS AND SOME GAPS IN THE ICE
OVER WESTERN LAKE SUPERIOR...THERE WILL BE OCNL -SHSN AT
KCMX...WHICH WILL ASSIST THE LOWER VISIBILITIES. DISTURBANCE SHOULD
INCREASE -SHSN FREQUENCY TODAY...AND THIS MAY RESULT IN VIS FALLING
MORE FREQUENTLY TO BLO 1/2SM. THERE SHOULD BE SOME IMPROVEMENT TO
IFR THIS EVENING AS WINDS VEER MORE TO THE NW AND DIMINISH SOME...
RESULTING IN LESS BLSN.
AT KIWD/KSAW...SRN EDGE OF STRATOCU/MVFR CIGS WILL BE NEAR KIWD
OVERNIGHT WHILE DOWNSLOPE WESTERLY WINDS WILL HELP TO MAINTAIN VFR
CONDITIONS AT KSAW. DEEPER MOISTURE/DISTURBANCE ROTATING INTO THE
AREA DURING THE DAY TODAY SHOULD PRODUCE A MORE SOLID MVFR CLOUD
DECK AS WELL AS SOME -SHSN/FLURRIES. AFTER THE STRONG WINDS OF
RECENT DAYS...THERE MAY BE SUFFICIENT OPEN WATER OVER WRN LAKE
SUPERIOR TO SUPPORT IFR CONDITIONS IN -SHSN AT KIWD THIS EVENING AS
WINDS VEER MORE TO THE NW.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 334 AM EST SUN FEB 23 2014
LOW PRESSURE OVER JAMES BAY TODAY WILL EXIT INTO QUEBEC TONIGHT.
EXPECT HIGH PRESSURE ACROSS SASKATCHEWAN TODAY TO SINK ACROSS THE
PLAINS STATES TUESDAY NIGHT INTO WEDNESDAY...ALLOWING A RIDGE TO
PASS OVER LAKE SUPERIOR TUESDAY AND TUESDAY NIGHT. W GALES 35-40KTS
WILL CONTINUE TODAY OVER PORTIONS OF MAINLY CENTRAL AND E LAKE
SUPERIOR IN BETWEEN THE EXITING LOW...AND NEARING HIGH PRESSURE FROM
THE NW.
LOW PRESSURE OVER NW MANITOBA WEDNESDAY MORNING WILL SWING ACROSS
LAKE SUPERIOR WEDNESDAY AFTERNOON AND EVENING BEFORE EXITING TO THE
NEW ENGLAND STATES. HIGH PRESSURE OVER CENTRAL CANADA AND ND
THURSDAY MORNING WILL BROADEN ACROSS THE UPPER GREAT LAKES THURSDAY
NIGHT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER WEATHER ADVISORY UNTIL 5 PM EST THIS AFTERNOON FOR MIZ001-
003.
LAKE SUPERIOR...
GALE WARNING UNTIL 7 PM EST /6 PM CST/ THIS EVENING FOR
LSZ240>246-263>267.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...TITUS
AVIATION...ROLFSON
MARINE...KF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
335 AM EST SUN FEB 23 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 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1152 PM EST SAT FEB 22 2014
WITH WEAKENING LOW PRES REMAINING IN THE VCNTY OF FAR NRN
ONTARIO/JAMES BAY AND HIGH PRES CONTINUING TO RIDGE SE FROM THE SRN
CANADIAN ROCKIES TO THE MID MISSISSIPPI VALLEY...BLUSTERY WESTERLY
WINDS WILL CONTINUE FOR MUCH OF THIS FCST PERIOD AT
KIWD/KCMX/KSAW...BUT ESPECIALLY AT THE MORE EXPOSED KCMX SITE. WITH
WINDS GUSTING OVER 30KT AT KCMX OVERNIGHT THRU THE AFTN...BLSN WILL
LIKELY KEEP PREVAILING VIS IN THE LIFR CATEGORY. EXPECT SOME
FLUCTUATION WITH VIS IMPROVING TO IFR FOR BRIEF PERIODS AS WELL AS
FALLING TO VLIFR. WITH THE WESTERLY WINDS AND SOME GAPS IN THE ICE
OVER WESTERN LAKE SUPERIOR...THERE WILL BE OCNL -SHSN AT
KCMX...WHICH WILL ASSIST THE LOWER VISIBILITIES. DISTURBANCE SHOULD
INCREASE -SHSN FREQUENCY TODAY...AND THIS MAY RESULT IN VIS FALLING
MORE FREQUENTLY TO BLO 1/2SM. THERE SHOULD BE SOME IMPROVEMENT TO
IFR THIS EVENING AS WINDS VEER MORE TO THE NW AND DIMINISH SOME...
RESULTING IN LESS BLSN.
AT KIWD/KSAW...SRN EDGE OF STRATOCU/MVFR CIGS WILL BE NEAR KIWD
OVERNIGHT WHILE DOWNSLOPE WESTERLY WINDS WILL HELP TO MAINTAIN VFR
CONDITIONS AT KSAW. DEEPER MOISTURE/DISTURBANCE ROTATING INTO THE
AREA DURING THE DAY TODAY SHOULD PRODUCE A MORE SOLID MVFR CLOUD
DECK AS WELL AS SOME -SHSN/FLURRIES. AFTER THE STRONG WINDS OF
RECENT DAYS...THERE MAY BE SUFFICIENT OPEN WATER OVER WRN LAKE
SUPERIOR TO SUPPORT IFR CONDITIONS IN -SHSN AT KIWD THIS EVENING AS
WINDS VEER MORE TO THE NW.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 334 AM EST SUN FEB 23 2014
LOW PRESSURE OVER JAMES BAY TODAY WILL EXIT INTO QUEBEC TONIGHT.
EXPECT HIGH PRESSURE ACROSS SASKATCHEWAN TODAY TO SINK ACROSS THE
PLAINS STATES TUESDAY NIGHT INTO WEDNESDAY...ALLOWING A RIDGE TO
PASS OVER LAKE SUPERIOR TUESDAY AND TUESDAY NIGHT. W GALES 35-40KTS
WILL CONTINUE TODAY OVER PORTIONS OF MAINLY CENTRAL AND E LAKE
SUPERIOR IN BETWEEN THE EXITING LOW...AND NEARING HIGH PRESSURE FROM
THE NW.
LOW PRESSURE OVER NW MANITOBA WEDNESDAY MORNING WILL SWING ACROSS
LAKE SUPERIOR WEDNESDAY AFTERNOON AND EVENING BEFORE EXITING TO THE
NEW ENGLAND STATES. HIGH PRESSURE OVER CENTRAL CANADA AND ND
THURSDAY MORNING WILL BROADEN ACROSS THE UPPER GREAT LAKES THURSDAY
NIGHT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER WEATHER ADVISORY UNTIL 5 PM EST THIS AFTERNOON FOR MIZ001-
003.
LAKE SUPERIOR...
GALE WARNING UNTIL 7 PM EST /6 PM CST/ THIS EVENING FOR
LSZ240>246-263>267.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...MRD
AVIATION...ROLFSON
MARINE...KF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1153 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 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1152 PM EST SAT FEB 22 2014
WITH WEAKENING LOW PRES REMAINING IN THE VCNTY OF FAR NRN
ONTARIO/JAMES BAY AND HIGH PRES CONTINUING TO RIDGE SE FROM THE SRN
CANADIAN ROCKIES TO THE MID MISSISSIPPI VALLEY...BLUSTERY WESTERLY
WINDS WILL CONTINUE FOR MUCH OF THIS FCST PERIOD AT
KIWD/KCMX/KSAW...BUT ESPECIALLY AT THE MORE EXPOSED KCMX SITE. WITH
WINDS GUSTING OVER 30KT AT KCMX OVERNIGHT THRU THE AFTN...BLSN WILL
LIKELY KEEP PREVAILING VIS IN THE LIFR CATEGORY. EXPECT SOME
FLUCTUATION WITH VIS IMPROVING TO IFR FOR BRIEF PERIODS AS WELL AS
FALLING TO VLIFR. WITH THE WESTERLY WINDS AND SOME GAPS IN THE ICE
OVER WESTERN LAKE SUPERIOR...THERE WILL BE OCNL -SHSN AT
KCMX...WHICH WILL ASSIST THE LOWER VISIBILITIES. DISTURBANCE SHOULD
INCREASE -SHSN FREQUENCY TODAY...AND THIS MAY RESULT IN VIS FALLING
MORE FREQUENTLY TO BLO 1/2SM. THERE SHOULD BE SOME IMPROVEMENT TO
IFR THIS EVENING AS WINDS VEER MORE TO THE NW AND DIMINISH SOME...
RESULTING IN LESS BLSN.
AT KIWD/KSAW...SRN EDGE OF STRATOCU/MVFR CIGS WILL BE NEAR KIWD
OVERNIGHT WHILE DOWNSLOPE WESTERLY WINDS WILL HELP TO MAINTAIN VFR
CONDITIONS AT KSAW. DEEPER MOISTURE/DISTURBANCE ROTATING INTO THE
AREA DURING THE DAY TODAY SHOULD PRODUCE A MORE SOLID MVFR CLOUD
DECK AS WELL AS SOME -SHSN/FLURRIES. AFTER THE STRONG WINDS OF
RECENT DAYS...THERE MAY BE SUFFICIENT OPEN WATER OVER WRN LAKE
SUPERIOR TO SUPPORT IFR CONDITIONS IN -SHSN AT KIWD THIS EVENING AS
WINDS VEER MORE TO THE NW.
&&
.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...
WINTER WEATHER ADVISORY UNTIL 5 PM EST SUNDAY 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...ROLFSON
MARINE...SRF
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
356 AM CST SUN FEB 23 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 353 AM CST SUN FEB 23 2014
ROAD SURFACES IN MANY AREAS CROSSED THE FREEZING MARK OVERNIGHT
AND THE SNOW MELTED AN REFROZE PRODUCING HAZARDOUS TRAVEL SO THE
WINTER WEATHER ADVISORY CONTINUES THIS MORNING.
AS ADVERTISED BY THE HIGH RESOLUTION MODELS...THE NAM...ARF...NMM
AND SREF...A COUPLED JET DEVELOPED ACROSS THE FORECAST AREA. THE
HEAVY SNOW WAS LOCALIZED ACROSS CHASE AND HAYES COUNTIES AND
PERHAPS A FEW OTHER AREAS. THE MODELS IN GENERAL SHOWED FAIR
SKILL FORECASTING THIS BUT NEAR ZERO SKILL IN LOCATION. 50 MILES
OF FORECAST ERROR WITH THE LOCATION. THE NAM BOUNCED AROUND
FAVORING CNTL LINCOLN COUNTY...THEN SRN LINCOLN COUNTY AND THEN
KEITH COUNTY. MODEL SKILL IN PREDICTING THE LOCATION OF MESOSCALE
HEAVY SNOW BANDS WAS POOR. THE WINTER STORM WARNING FOR CHASE AND
HAYES COUNTIES CONTINUES THIS MORNING. THE RADAR OUT OF KGLD
CONTINUES TO SHOW LIGHT TO MODERATE SNOW AS THIS FORMERLY HEAVY
BAND OF SNOW IS WEAKENING.
THE LATEST RADAR OUT OF KCYS IN CONJUNCTION WITH THE RAP AND NAM
MODELS SUGGESTS A SECOND BAND OF LIGHT TO MODERATE SNOW WILL MOVE
INTO WRN NEBRASKA THIS MORNING AND THEN LIFT SLOWLY NORTH AS A
DEVELOPING WARM FRONT THIS AFTERNOON AND TONIGHT. BARRING THE
DEVELOPMENT OF AN ORGANIZED HEAVY SNOW BAND...IT IS BELIEVED
SNOWFALL AMOUNTS TODAY WILL BE AN INCH OR LESS USING A 13 TO 1
RATIO WHICH HAS BEEN THE PREVAILING MARKER OUTSIDE OF THE HEAVY
SNOW BAND WHICH DEVELOPED ACROSS FAR SOUTHERN NEBRASKA LAST NIGHT.
THUS FAR...KLBF MEASURED 0.19 INCHES OF LIQUID WITH ABOUT 2
INCHES OF SNOWFALL. AN ADDITIONAL 0.08 IS FORECAST TODAY FOR A
TOTAL OF 0.27 INCHES. YESTERDAYS MODEL MEDIAN QPF WHICH WAS USED
FOR THE FORECAST WAS 0.28. THUS THE ACCURACY OF THE SNOWFALL
FORECAST HINGES ON THE SNOW TO WATER RATIO WHICH IS HIGHLY
DEPENDENT ON DEEP LIFT TO PRODUCE HIGH RATIOS.
THE COBB METHODOLOGY CONTINUES TO ADVERTISE VERY HIGH RATIOS OF
17 TO 20 TO 1 TODAY AND TONIGHT. THESE RATIOS ARE SUSPECT AND
LIKELY BIASED TOWARD THE DEVELOPMENT OF DEEP VERTICAL LIFT SO 13
TO 1 WAS USED TODAY. THE HIGH COBB RATIOS WERE USED
TONIGHT...NEAR 20 TO 1 AT KVTN...BUT HPC HAS OUTLOOKED THIS AREA
FOR SLIGHT RISK OF 4 INCHES OF ACCUMULATION. THE MEDIAN QPF AT
KVTN IS ABOUT 0.15 INCHES AND THE FORECAST IS FOR 0.15. THE 20 TO
1 RATIO THEN PRODUCES 3 INCHES OF SNOW FOR VALENTINE.
THE NAM SUGGESTS GENERALLY MODERATE LIFT AND MID LEVEL
FRONTOGENESIS TONIGHT ACROSS THE NORTH...NO WHERE NEAR THE
STRENGTH EXHIBITED BY THE COUPLED JET STRUCTURE SATURDAY NIGHT
ACROSS THE SOUTH BUT THERE IS POTENTIAL FOR A PERIOD OF MODERATE
SNOW AS THERE IS BANDING POTENTIAL. GIVEN THE UNCERTAINTIES OF
FCSTING BANDED SNOW...A MIDDLE OF THE ROAD FORECAST IS IN PLACE
FOR THE NORTH TONIGHT.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 353 AM CST SUN FEB 23 2014
MONDAY MORNING WILL CONTINUE TO SEE SNOW ACROSS THE NORTHERN PART
OF THE CWA AS THE NEXT WAVE CONTINUES TO PUSH ACROSS S DAKOTA AND
NORTHEAST NEB. MODELS ARE IN FAIR AGREEMENT WITH THE BAND OF SNOW
TO LINGER THROUGH MONDAY MORNING THEN DIMINISHES FOR THE
AFTERNOON. HIGHEST AMOUNTS OF ADDITIONAL SNOW LIKELY AROUND AN
INCH IN THE MORNING BEFORE BECOMING LIGHT AND PUSHING EAST.
HOWEVER YET ANOTHER DISTURBANCE IS FORECAST TO TRACK ACROSS THE
HIGH PLAINS FOR LATE MONDAY INTO TUESDAY. COLD ARCTIC HIGH
PRESSURE WILL BEGIN TO PUSH ACROSS SOUTHERN CANADA BY MONDAY
EVENING. THIS WILL BRING IN SOME DRIER AIR ACROSS THE NORTHERN
PLAINS WITH THE MAIN SNOW BANDING EXPECTED ACROSS THE SOUTHWESTERN
PART OF THE CWA. DEPTH OF THE DENDRITIC GROWTH ZONE IS FAIRLY
DEEP...HOWEVER THE BEST OMEGA IS ACROSS THE HIGHER TERRAIN TO THE
WEST. WILL HAVE TO OVER COME A SOMEWHAT DRY LOWER LEVEL WITH TOP
DOWN SATURATION...ALTHOUGH SHOULD RESULT IN AROUND AN INCH OR TWO
OF SNOW. IF A BAND OF SNOW BECOMES MORE STATIONARY...WHICH IS NOT
SUGGESTED AT THIS TIME BY THE MODELS...BUT AFTER SEE LAST NIGHTS
BAND CAN NOT BE RULED OUT...ANOTHER ADVISORY FOR 2 TO 4 INCHES
WOULD BE WARRANTED.
THE COLD HIGH PRESSURE WILL BEGIN TO BE NOTICES WITH TEMPS
FALLING TO NEAR ZERO FOR TUESDAY MORNING. TUESDAY AFTERNOON AS
THE SNOW DIMINISHES FROM THE NORTH...CLOUDS WILL BE ON THE
DECREASE. COLD ARCTIC AIR WILL SPREAD ACROSS THE AREA WITH HIGHS
STRUGGLING INTO THE 20S. BY TUESDAY NIGHT THE DISTURBANCE WILL BE
SE AND CLEARING SKIES ASSOCIATED WITH THE SFC HIGH WILL COMBINE
WITH THE SNOW PACK TO PRODUCE A VERY COLD LATE FEBRUARY NIGHT.
WIDESPREAD SINGLE DIGITS...AND MOST NOT TO FAR FROM ZERO. LOCALLY
BELOW ZERO STILL POSSIBLE...HOWEVER CENTER OF THE HIGH IS OVER
HEAD CLOSER TO MIDNIGHT SO TEMPS MIGHT BEGIN TO CLIMB OR AT LEAST
HOLD STEADY FOR THE EARLY MORNING HOURS.
SW WINDS DEVELOP FOR WED...ON THE BACK SIDE OF THE HIGH...WITH
WARMER AIR TO PUSH ACROSS THE AREA. HIGHS WARM INTO THE
30S...HOWEVER SNOW PACK COULD PLAY A ROLL IN TEMPS BELOW GUIDANCE.
REST OF THE WORK WEEK WILL CONTINUES TO SEE A RIDGE ACROSS THE
SOUTHERN ROCKIES WHICH TRAILS TO THE NW INTO THE PAC NORTHWEST.
THIS FAVORS A NORTHWEST FLOW AND PROGRESSIVE CLIPPER SYSTEM AND ON
AND OFF CLOUDS AND MAYBE SOME LIGHT SNOW. BY THE WEEKEND BOTH THE
GFS AND THE EC ARE CARVING A TROUGH ACROSS THE WESTERN CONUS WITH
MORE ZONAL FLOW EAST OF THE ROCKIES. WILL CONTINUE TO MONITOR THIS
SYSTEM WHICH MODELS EJECT ONTO THE PLAINS LATE SATURDAY INTO
SUNDAY. STILL A WEEK OUT BUT SOMETHING TO MONITOR.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1128 PM CST SAT FEB 22 2014
VISIBILITY WILL CONTINUE TO BE LESS THAN 3SM THROUGH THE NIGHT FOR
THE AREA ALONG AND SOUTHWEST OF A BBW-TIF-IEN LINE WITH LOCALIZED
VISIBILITY AT OR BELOW 1SM IN THE SOUTHWEST ALONG AND SOUTH OF AN
OGA-LBF LINE. CEILING WILL CONTINUE TO BE 1000-2000 FEET AGL IN
THE SOUTHWEST THROUGH AT LEAST SUNDAY EVENING 03Z.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL NOON CST /11 AM MST/ TODAY FOR
NEZ022>025-035>038-056>059-071.
WINTER STORM WARNING UNTIL NOON CST /11 AM MST/ TODAY FOR NEZ069-
070.
&&
$$
SHORT TERM...CDC
LONG TERM...MASEK
AVIATION...SPRINGER
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1147 PM CST SAT FEB 22 2014
.UPDATE...
ISSUED AT 939 PM CST SAT FEB 22 2014
PER COORDINATION AND WHERE CURRENT SNOW BAND IS SETTING UP...HAVE
EXPANDED WINTER WEATHER ADVISORY TO INCLUDE FURNAS AND HARLAN COUNTIES.
UPDATE ISSUED AT 859 PM CST SAT FEB 22 2014
COMPLICATED FORECAST AS WE HEAD INTO TONIGHT AS TO WHERE SNOW
BANDS WILL SET UP. HAVE BEEN MONITORING SNOW BAND ACROSS WESTERN
NEB WHICH HAS MIGRATED EASTWARD EARLY THIS EVENING. DRIER AIR TO
THE EAST HAS BEEN SLOW TO OVERCOME BUT A SNOW BAND HAS MANAGED TO
MOVE IN AND IS ORIENTED W/E GENERALLY FM KLBF TO KLXN TO KHDE AND
POINTS JUST TO THE SOUTH. THE SNOW IS ALIGNED FAIRLY WELL WITH THE MID
LEVEL FRONTOGENESIS WHICH IS PRIMARILY PROGGED ALONG OUR WESTERN
CWA THROUGH THE FIRST PART OF THE NIGHT. HAVE EXPANDED OUR CURRENT
WINTER WX ADVISORY TO INCLUDE PHELPS AND KEARNEY COUNTIES WHERE
SNOW HAS COMMENCED AND A LONGER DURATION OF SNOW IS EXPECTED. AS
WE HEAD INTO TONIGHT WE SEE AN INCREASE IN ISENTROPIC LIFT AS
INDICATED ON THE 290K SURFACE AND THE LIFT PERSISTS FOR SEVERAL
HOURS...INTO SUNDAY MORNING. THE UPPER JET STREAK NOSES ACROSS
WESTERN NEB SUNDAY MORNING WITH LIFT CONTINUING SUNDAY MORNING IN
LFQ OF JET. ONE OF THE MORE NOTABLE CHANGES IN THE LATEST MODEL
RUNS THAT SNOW IS EXPECTED TO PERSIST LONGER SUNDAY MORNING WITH
ADDITIONAL LIGHT ACCUMULATIONS POSSIBLE. SNOW AMOUNTS WILL BE
DEPENDENT UPON SNOW BANDS WITH SEVERAL INCHES...AND LOCALLY HEAVY
SNOWFALL POSSIBLE WITHIN THE BANDS.
&&
.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 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1139 PM CST SAT FEB 22 2014
DETERIORATING CONDITIONS ARE ANTICIPATED AT KGRI OVER THE NEXT FEW
HOURS AS LIGHT SNOW OVERTAKES THE TERMINAL. WHILE WINDS WILL NOT
BE PARTICULARLY STRONG...COULD SEE VSBYS DROP DOWN TO NEAR 2SM IN
HEAVIER BANDS OF SNOW AS THEY DEVELOP AND CEILINGS LOWER TO NEAR
1500FT. OTHERWISE...SNOWFALL SHOULD BEGIN TO TAPER OFF DURING THE
LATER MORNING HOURS...WITH MVFR CEILINGS ANTICIPATED TO PERSIST
FOR MUCH OF THE DAY BEHIND THIS DEPARTING DISTURBANCE.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...WINTER WEATHER ADVISORY UNTIL NOON CST SUNDAY FOR NEZ060-061-
072>074-082-083.
KS...NONE.
&&
$$
UPDATE...FAY
SHORT TERM...HALBLAUB
LONG TERM...WESELY
AVIATION...ROSSI
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1242 AM EST SUN FEB 23 2014
.SYNOPSIS...
AN UPPER LEVEL DISTURBANCE WILL BRING THE CHANCE FOR SNOW SHOWERS
LATE TONIGHT...AND RAIN OR SNOW SHOWERS ON SUNDAY. COLDER AIR
WILL RETURN FOR THE BEGINNING OF THE WORK WEEK WITH LAKE EFFECT
SNOWS OVER CENTRAL NEW YORK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
8 PM UPDATE... THE CURRENT FCST IS IN FAIRLY GOOD SHAPE...SO ONLY RELATIVELY
SMALL CHGS WERE MADE ATTM.
RGNL RADAR IMAGERY SHOWS A NARROW BAND OF LGT PCPN (MAINLY -SN)
EXTENDING FROM CNTRL IL-NRN IN-NRN OH-NW PA THIS EVE. THE LATEST
RUC-13 AND HRRR OUTPUT APPEAR TO BE DOING A REASONABLY GOOD JOB
HANDLING THE EVOLUTION OF THIS PCPN SO FAR. BOTH MODELS SUGGEST IT
WILL STREAK INTO THE TWIN TIERS BY 06-09Z...THEN EXIT BY ARND 15Z
SUN MRNG...UNDERNEATH DECENT 850-700 MB FGEN FORCING. THE MAIN
FACTORS GOING AGAINST PCPN DVLPMT LOCALLY ARE DRY LOW-LVL AIR TO
OVERCOME INITIALLY...AND ALSO NON-DESCRIPT JET DYNAMICS.
OVERALL...WE FELT THE COURSE OF LEAST REGRET WAS TO BUMP POPS UP
TO LIKELY VALUES WHERE WE HAVE SOME LGT SNOW ACCUMS MENTIONED LTR
TNT INTO EARLY SUN (MOSTLY ACRS NY`S SRN TIER...WITH MAX AMTS
GENERALLY 1" OR LESS). SHSN SHOULD DIMINISH QUICKLY TO FLRYS LTR
SUN MRNG...THEN END ALTOGETHER BY MIDDAY.
OTHWS...OUR TEMP/DEW PT GRIDS WERE MASSAGED SLIGHTLY THIS EVE...TO
BEST REFLECT THE LATEST OBSERVATIONAL TRENDS.
PREV DISC... 330 PM UPDATE...
WEAK DISTURBANCE OVER THE OHIO VALLEY CREATING LIGHT PRECIPITATION
OVER IL/IN WILL MOVE OUR WAY TONIGHT. I FOUND ONE OB TO THE WEST
SHOWING 2 1/2SM IN SNOW. BASED ON THIS AND MODEL QPF...NOT
EXPECTING MUCH MORE THAN A LIGHT DUSTING OF SNOW TONIGHT
ESPECIALLY NEAR OR JUST NORTH OF THE NY/PA LINE.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH TUESDAY/...
330 PM UPDATE...
DISTURBANCE ABOVE MAY CONTINUE A FEW SNOW SHOWERS INTO MIDDAY
SUNDAY BEFORE ENDING AS A SPRINKLE OR FLURRY. NOT EXPECTING MUCH.
BIGGER STORY WILL BE MUCH COLDER AIR BUILDING IN SUNDAY NIGHT AND
LASTING THROUGH TUESDAY. LAKE SNOWS LOOK LIKELY WITH A FLOW
SETTLING IN BETWEEN 290 AND 270. ONE LIMITING FACTOR AT LEAST
DURING THE DAY MAY DIURNAL EFFECTS. TAKE MONDAY AFTERNOON FOR
EXAMPLE WITH NAM BUFKIT PROFILES SHOWING SURFACE BASED CAPE OF
ABOVE 40 J/KG. BASED ON LOCAL RESEARCH, THESE VALUES COUPLED WITH
LOW TO MODERATE SHEAR WOULD PROMOTE MORE OF A DIFFUSE BAND OR OPEN
CELLULAR SNOW SHOWERS DURING THE AFTERNOON THAN A WELL DEFINED
BAND. WITH THAT IN MIND TRIED TO SHOW THE BEST ACCUMS OF AT LEAST
A FEW INCHES DURING THE NIGHTTIME AND EARLY PART OF THE DAY. COULD
SEE NEEDING AN ADVISORY AT SOME POINT DOWN THE ROAD BUT A WARNING
DOES NOT SEEM LIKELY...THUS AFTER COORDINATION WITH BUFFALO NO
LAKE EFFECT WATCH AT THIS POINT. HIGHS GENERALLY IN THE 20S
THROUGH TUESDAY. I DIDN`T TOUCH TUESDAYS HIGHS OF IN THE 20S. I
DID NOTICE MODEL GUIDANCE, ALMOST ALL OF IT, IS IN THE TEENS. WILL
BE INTERESTING TO SEE WHAT HAPPENS AS 925S SUPPORT OUR HIGHS OF 20S.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
MEDIUM RANGE MODELS CONTINUE TO SHOW EXCELLENT AGREEMENT THROUGH
THE EXTENDED PERIOD BOTH ALOFT AND AT THE SFC. IN GENERAL THE
PERIOD WILL BE VERY COLD WITH TEMPS RUNNING 15 TO 25 DEGREES
BELOW SEASONAL NORMALS. TUESDAY NIGHT INTO WED, MODELS INDICATE SFC
LOW PRES WELL OFF THE MID ATLANTIC COAST WITH THE GFS FURTHER OUT
TO SEA THAN THE ECMWF. CURRENT MODEL TREND IS FOR AN EVEN MORE
EASTERLY TRACK SO WILL CONTINUE WITH JUST CHC POPS THROUGH THIS
PERIOD. REST OF FORECAST LOOKS PRIMARILY DRY WITH SCATTERED LAKE
EFFECT SNOW SHOWERS AND FLURRIES EAST/SOUTHEAST OF LAKE ONTARIO.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
06Z UPDATE...
VFR AT ALL SITES WITH NARROW BAND OF MID-LVL CLOUDS ACRS NY
TERMINALS. THIS NARROW BAND IS ASSOCIATED WITH LIGHT SNOW BUT IS
EXPECTED TO WEAKEN AS IT MOVES OFF TO THE EAST. THUS HAVE KEPT
MVFR TEMPO/D INTO KITH/KELM AND KBGM FROM 08Z-12Z AT TERMINALS BUT
HAVE BROUGHT VSBYS UP TO 5SM. IF TREND OF WEAKENING CONTINUES,
WILL REMOVE COMPLETELY BUT NOT CONFIDENT ENOUGH AS IT CONTINUES TO
BE ON TERMINALS` DOORSTEP.
FURTHER NORTH AT KSYR AND KRME EXPECT VFR THROUGH THE NEXT 24
HOURS, THOUGH APPEARS THAT LAKE EFFECT WILL TRY TO DEVELOP AFTER
MIDNIGHT. HOWEVER WHERE THIS SETS UP REMAINS IN QUESTION AND WILL
EVALUATE MORE FOR 12Z ISSUANCE.
ANOTHER WAVE WILL ZIP ACROSS PENNSYLVANIA LATE TONIGHT AND MAY
BRING LIGHT SNOW TO AVP, THUS HAVE INCLUDED PROB30 MENTION BETWEEN
03Z AND 06Z. NORTHWEST FLOW BEHIND WAVE WILL KICK IN ACROSS NY
TERMINALS AFTER 00Z AND THIS MAY LEAD TO MVFR CIGS DEVELOPING AT
KITH TOWARD 06Z MON.
WSW WINDS AROUND 10KTS TONIGHT WILL CONTINUE THROUGH THE DAY.
OUTLOOK...
LATE SUN NGT THROUGH TUE ATN...MVFR/IFR RESTRICTIONS IN LAKE
EFFECT -SHSN CNTRL NY TERMINALS.
TUE NGT THROUGH THU...RESTRICTIONS POSSIBLE IN SCATTERED SNOW
SHWRS.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...HEDEN
NEAR TERM...HEDEN/MLJ
SHORT TERM...HEDEN
LONG TERM...RRM
AVIATION...PVN
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
301 AM CST SUN FEB 23 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 301 AM CST SUN FEB 23 2014
CURRENTLY AS OF 09Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED RIDGING FROM THE EASTERN PACIFIC INTO ALASKA...A BROAD UPPER
LOW OVER THE CANADIAN ARCHIPELAGO...AND BROAD TROUGHING ACROSS ALL
OF SOUTHERN CANADA INTO THE UPPER MIDWEST. SHORTWAVES OF NOTE FOR
THIS FORECAST INCLUDE ONE OVER WEST CENTRAL BRITISH COLUMBIA...ONE
OVER CENTRAL ALBERTA...AND THE LAST AS PART OF THE UPPER LOW ON THE
WESTERN SIDE OF THE CANADIAN ARCHIPELAGO. A NORTHWEST 925MB FLOW
CONTINUES TO GRADUALLY DRAW COLDER IN OUT OF CANADA TOWARDS THE
FORECAST AREA...NOTED BY THE 00Z MPX SOUNDING AT -15C. THAT SAME
SOUNDING ALSO CONTINUES TO DEPICT PLENTY OF DRY AIR...RESULTING IN
CLEAR SKIES EARLY THIS MORNING. COMBINATION OF THE CLEAR SKIES AND
COOLING 925MB TEMPS HAS ALLOWED TEMPERATURES TO DROP INTO THE SINGLE
DIGITS ABOVE ZERO. IF THE 5 TO 15 MPH BREEZE WAS NOT PRESENT TO KEEP
THE AIR MIXED...TEMPERATURES WOULD PROBABLY BE A LOT COLDER.
OVERALL LITTLE CHANGE IS PROGGED BY MODELS TO OCCUR IN THE NEXT 24
HOURS IN TERMS OF THE UPPER LEVEL PATTERN OVER THE UPPER MIDWEST AND
THE FORECAST AREA. WE STILL REMAIN UNDER THE INFLUENCE OF A DRY
NORTHWEST LOW TO MID LEVEL FLOW...WHICH SHOULD HELP KEEP SKIES
MAINLY CLEAR THROUGH TODAY AND MUCH OF TONIGHT. THERE ARE SOME
INDICATIONS OF CIRRUS APPROACHING LOCATIONS WEST OF THE MISSISSIPPI
RIVER LATE TONIGHT...BUT THATS REALLY ABOUT IT FOR CLOUDS.
925MB TEMPS TODAY ARE FORECAST TO RANGE BETWEEN -13 AND -16C...ABOUT
1-2C COLDER THAN YESTERDAY. THEREFORE...WE SHOULD SEE HIGHS JUST
SLIGHTLY COOLER THAN YESTERDAY. SKIES STAYING CLEAR THROUGH
MUCH OF TONIGHT PLUS 925MB TEMPS FALLING TO -14 TO -19C...COLDEST
OVER WISCONSIN...SHOULD ALLOW FOR LOWS IN MOST LOCATIONS IN THE
SINGLE DIGITS BELOW ZERO. AGAIN...THERE LOOKS TO BE A PERSISTENT
NORTHWEST BREEZE THROUGH TONIGHT HELPING TO PREVENT DECOUPLING.
STILL...THE TYPICAL COLD SPOTS COULD TRY TO APPROACH -10F. WIND
CHILLS LOOK TO GET CLOSE TO ADVISORY CRITERIA...BUT TOO MARGINAL AT
THIS POINT TO ISSUE AN ADVISORY.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 301 AM CST SUN FEB 23 2014
THE 2 MAIN IMPACTS REMAIN FOR THE LONG TERM...
1. POTENTIAL FOR SOME SNOW LATE MONDAY AFTERNOON AND NIGHT
2. THE BITTER COLD AIR...ESPECIALLY TUESDAY NIGHT AND BEYOND.
REGARDING IMPACT NUMBER 1...THE SHORTWAVES CURRENTLY OVER CENTRAL
BRITISH COLUMBIA AND ALBERTA REMAIN PROGGED TO PHASE TOGETHER OVER
THE DAKOTAS ON MONDAY...THEN QUICKLY SLIDE THROUGH THE FORECAST AREA
AROUND 06Z TUESDAY. MOISTURE IS LACKING FOR THESE SHORTWAVES...WITH
PRECIPITABLE WATER CLIMBING TO 0.1-0.2 OF AN INCH. HOWEVER...SOME
WEAK ISENTROPIC LIFT ON THE 275-280K SURFACES COMBINED WITH DPVA
AHEAD OF THE SHORTWAVES SHOULD BE ENOUGH TO SQUEEZE OUT SOME LIGHT
SNOW. SNOW SHOULD BE SOMEWHAT FLUFFY...THOUGH THE BULK OF THE LIFT
LOOKS TO OCCUR ABOVE THE DENDRITIC GROWTH ZONE. TIMING WISE...MODELS
CONTINUE TO SLOW DOWN THE SNOW MOVING INTO THE AREA...WITH THE
23.00Z NAM/GFS/CANADIAN/ECMWF KEEPING MUCH OF THE SNOW WEST OF THE
AREA PRIOR TO 00Z TUESDAY. ITS MORE OF A MONDAY NIGHT SNOW NOW. DID
RAISE CHANCES UP FOR MONDAY EVENING WEST OF THE MISSISSIPPI RIVER
WITH GOOD MODEL AGREEMENT FOR THE SNOW THEN. AFTER 06Z MONDAY...
MODELS DIVERGE ON HOW MUCH SNOW MIGHT BE LEFT WITH THE 23.00Z
GFS/CANADIAN DRY WHEREAS THE NAM AND ECMWF STILL HAVE SOME SNOW
LEFT. SPLIT THE DIFFERENCE AND HAVE SOME 20-30 PERCENT CHANCES FOR
NOW. IT APPEARS MUCH OF THIS HAS TO DO WITH THE TIMING OF THE PHASED
SHORTWAVE.
NOW IMPACT NUMBER 2...THE COLD. IN THE WAKE OF MONDAY NIGHTS
SHORTWAVE TROUGH...925MB TEMPS FALL TO -15 TO -20C. A SECOND AND
MORE POTENT COLD SURGE REMAINS PROGGED TO PLUNGE INTO THE AREA
TUESDAY NIGHT...DROPPING 925MB TEMPS TO -23 TO -25C BY 12Z
WEDNESDAY. THIS SURGE IS BEHIND THAT SHORTWAVE CURRENTLY OVER THE
CANADIAN ARCHIPELAGO. WIND CHILL ADVISORIES SEEM ALL BUT LIKELY
TUESDAY NIGHT INTO WEDNESDAY MORNING. A BRIEF BOUT OF WARM ADVECTION
IS SUGGESTED FOR WEDNESDAY AHEAD OF AN ARCTIC COLD FRONT
DROPPING SOUTH OUT OF CANADA...THOUGH IT APPEARS A BRISK WEST WIND
WILL ACCOMPANY IT. THEN ITS BACK TO THE COLD AS ANOTHER IMPRESSIVE
SURGE OF ARCTIC AIR DIVES SOUTH INTO THE REGION FOR THURSDAY ON
SOME BRISK NORTHWEST WINDS. 925MB TEMPS FROM THE 23.00Z GFS AND
ECMWF DROP TO -23 TO -27C BY 12Z THURSDAY...WHILE 850MB TEMPS
APPROACH -30C ACROSS OUR NORTH. THESE READINGS ARE NEARLY 3 STANDARD
DEVIATIONS BELOW NORMAL. BEYOND THURSDAY...MODELS BEGIN TO DIVERGE
A BIT WITH THE HANDLING OF THE COLD AIR. THE 23.00Z GFS TRIES TO
MODIFY THE COLD AIR SOMEWHAT FROM THE FLOW BECOMING MORE ZONAL
ACROSS THE NORTHERN TIER OF THE U.S.. THE 23.00Z ECMWF ALONG WITH
EXTRAPOLATION OF THE CANADIAN HAS THAT SAME ZONAL FLOW...JUST A
SMIDGE FURTHER SOUTH...WHICH RESULTS IN A CONTINUATION OF THE DEEP
FREEZE. FOR THE FORECAST LEANED A BIT CLOSER TOWARDS THE ECMWF.
OVERALL FOR TEMPERATURES TUESDAY THROUGH SATURDAY...STAYED CLOSE TO
A CONSENSUS OF 30 DAY BIAS CORRECTED GUIDANCE...WHICH PERFORMED WELL
IN PAST COLD SPELLS THIS WINTER. THURSDAY NIGHT COULD BE VERY COLD
WITH A SURFACE RIDGE PARKED OVERHEAD. WOULD NOT BE SURPRISED IF
SOME OF THE TYPICAL COLD SPOTS TO APPROACH -30F.
GIVEN HOW DEEP SOME OF THE FROST IS ALREADY...WATER MAINS UNDER
ROADS WILL NEED TO BE WATCHED CLOSELY. LUCKILY THE HIGHER SUN ANGLE
CAN HEAT THE TOP OF THE ROAD SURFACES MORE NOW THAN IN JANUARY...BUT
STILL THIS COLD AIR WILL NOT BE GOOD. THERE ARE STRONG INDICATIONS
TOO FROM THE CFS THAT THE BELOW NORMAL WEATHER COULD PERSIST THROUGH
ALL OF MARCH.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1110 PM CST SAT FEB 22 2014
VERY LITTLE CHANGE IN CONDITIONS EXPECTED THROUGH SUNDAY EVENING.
HIGH PRESSURE WILL REMAIN CENTERED OVER SASKATCHEWAN WITH THE
RIDGE FROM THE HIGH EXTENDING SOUTHEAST INTO IOWA AND MISSOURI
WHILE LOW PRESSURE REMAINS CENTERED NEAR HUDSONS BAY. THE GRADIENT
BETWEEN THESE TWO FEATURES WILL KEEP THE WINDS OUT OF THE WEST TO
NORTHWEST AT SPEEDS OF 10 TO 15 KNOTS. COULD GET A LITTLE GUSTY
SUNDAY AFTERNOON AT KRST AND HAVE INCLUDED THESE IN THE FORECAST
BEFORE THE INVERSION DEVELOPS AND CUTS OFF THE MIXING EARLY IN THE
EVENING.
&&
.CLIMATE...
ISSUED AT 301 AM CST SUN FEB 23 2014
GIVEN ALL THE COLD AIR TO ROUND OUT THE MONTH OF FEBRUARY...HERE IS
HOW FEBRUARY AND THE WINTER WOULD STACK UP BASED ON THE CURRENT
FORECAST...
...FOR THE MONTH OF FEBRUARY...
LA CROSSE... 9.5 AVERAGE TEMPERATURE...4TH COLDEST
COLDER FEBRUARYS...
1873... 3.9
1936... 4.3
1899... 9.4
ROCHESTER... 6.9 AVERAGE TEMPERATURE...4TH COLDEST
COLDER FEBRUARYS...
1936... 0.5
1979... 5.7
1917... 6.0
...FOR THE WINTER...DECEMBER THROUGH FEBRUARY...
LA CROSSE... 11.6 AVERAGE TEMPERATURE...5TH COLDEST
COLDER WINTERS...
1872-1873... 8.4
1874-1875... 10.5
1977-1978... 11.4
1935-1936... 11.4
ROCHESTER... 8.9 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
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
525 AM EST Sun Feb 23 2014
...Small Hail and Frequent Lightning Possible Along the Panhandle
Coast This Morning...
.Mesoscale Update...
A cluster of storms off of the panhandle coast will move ashore
over the next hour or so. These storms have been producing
frequent lightning, heavy rain, and may contain some small hail.
As the morning progresses, the hail threat will diminish and the
focus will shift to primarily heavy rain. See previous discussions
below.
&&
.Prev Discussion [355 AM EST]...
.Near Term [Through Today]...
The large scale pattern is highlighted by a persistent broad trough
over much of Conus. This leaves nearly zonal flow over NE Gulf
region. However a series of shortwaves will continue to move Ewd
providing increasing clouds and just enough lift that when combined
with surface features will maintain an unsettled weather pattern
today. Mid-High clouds streaming Ewd overnight assocd with lead
shortwave moving Ewd across mid-South will cross NE Gulf region
later today with the forecast area in the right entrance region of
the upper jet. At surface...in response to Ewd moving shortwave...
W-E warm front located across the Nrn Gulf waters Ewd across N/Cntrl
FL overnight will lift Nwd to coast by sunrise then to vcnty of I-10
during the day with light Sly flow in its wake. Upstream cold front
across mid-South around sunrise moves SEWD to Ern TN/N-Cntrl AL/Srn
MS by sundown with WAA and isentropic upglide spreading over our
area. Early radar showing leading edge of moisture approaching wrn
most Panhandle waters.
Patchy to areas of fog initially south of I-10 will accompany rain
and spread E/N thru the day. The combination of upper and lower
features will yield an expansive area of showers with isolated to
sct thunderstorms (highest Panhandle waters) moving SW-NE to reach
our Wrn CWA around sunrise and then progress EWD. Afternoon dew
point will rise from mid 60s coast to upper 50s Nrn tier AL/GA
counties. This depicted well in HRRR and other High Res guidance.
Limited mid-level lapse rates and a relatively cool boundary layer
should limit the potential for any strong storms. Best chance per
CAM would be Panhandle waters. However, with the upper flow parallel
to the warm boundary, main concern is training of cells is possible
with locally heavy rainfall possible especially during the aftn QPF
south of FL border exceeding 1 inch. Will go with 70-30% W-E POP
gradient in morning then 80-40% in the afternoon. Temperatures will
be tricky, depending on the eventual position of the warm front and
the coverage of the rainfall. However, expect warmest temperatures
along and south of I-10 (lower 70s), with lower to mid 60s for much
of SE AL and SW GA.
.Short Term [Tonight Through Tuesday]...
By the time the evening rolls around, the polar jet max will be
racing east and the northern stream trough will dip a bit deeper
into the Southeast. This will act to better stack the frontal
system as surface high pressure presses a cold front into our
region. The surface cold front will merge with Sunday`s warm front
and settle in over north Florida before deep layer zonal flow sets
in and stalls the frontal system once again. As the two fronts
merge, and the system stacks, we`ll likely see a brief uptick in
shower activity along the surface front. Expect rainfall to be
much lighter than Sunday afternoon as the surge of more tropical-
like moisture will have moved east.
On Monday, a southern stream impulse will be lifting north
through the northern Gulf, eventually aligning with the surface
front and pressing the northern stream trough back to the north
out of our area. Exactly where the surface front will be is a bit
uncertain, though the most likely scenario would place the front
along or south of I-10 in north Florida, possibly as far south as
the extreme northern Gulf. Should the surface front be positioned
across north Florida, things could become interesting with respect
to the potential for an isolated strong storm. Due to the limited
tropospheric penetration of the southern stream impulse, the mid-
level cooler/drier air will not be forced as aggressively to the
north. This will effectively steepen mid-level lapse rates across
the Tri-State region with deep layer shear around 60 knots more
than sufficient to support organized updrafts. In the other
corner, slightly warmer mid/upper level temps where the northern
stream trough has retreated a bit, will essentially cap the
potential for deep moist convection, though as the southern stream
impulse moves away, cooler mid/upper temps may slide back south late
in the day, eroding the cap. Bottom line is that there is a very low
potential for strong storms on Monday, though should convection
get going, and should the mid/upper level cap erode the potential
exists for a storm or two to produce gusty winds and possibly some
small hail.
Tuesday, is really the more interesting day as a more potent
southern stream impulse races east out of Texas, through the lower
MS Valley and into the southeast by the late afternoon. Should we
be able to mix out the mid-level cap early enough that the
shortwave is overhead, we`d be able to tap into some rather steep
lapse rates and strong deep layer shear. This could support the
development of more severe level storms with the threat for
damaging winds and hail.
So, through Tuesday expect showers and isolated storms to be
around. Most likely across north Florida Monday, spreading further
inland and increasing in coverage on Tuesday. The potential for a
strong storm or two exists on Monday, with a chance for severe
storms on Tuesday. Uncertainty remains very high regarding strong
to severe storms, as my lengthy discussion above lays out all of
the variables that must align just right. Expect above average
temperatures, in the middle to even upper 70s in some spots, both
Monday and Tuesday.
.Long Term [Tuesday Night Through Sunday]...
A cold front will move through Wednesday with a chance of showers
and thunderstorms. Behind the front high pressure will build in
bringing cooler temperatures and drier air. The models differ with
a series of low pressure systems at the end of the period. The GFS
has precipitation moving across central Florida Friday and a low
developing off the East coast near Georgia and South Carolina
followed by another low forming over Texas. The Euro has a Gulf
low forming near the Texas/Louisiana border Friday night then
moving across north Florida Saturday.
.Aviation...
[Through 06Z Monday]
MVFR CIGS should develop during the predawn hours or shortly after
sunrise at ECP, TLH and VLD, lowering to IFR CIGS during
the morning hours. There will be a chance of MVFR CIGS at DHN and
ABY during the day tomorrow as well. With a prolonged rain event
any improvement in evening VSBYS/CIGS will begin to again lower
after 02z and winds die off. Rain and isold thunderstorms will move
in from the west during the morning. Heaviest rain and thunderstorm
activity will likely be focused in Florida Panhandle particularly at
ECP, but also possibly affecting TLH. Main impact would be through
reduced visibility due to very heavy rain. Thunderstorms may also
linger at ECP or TLH south of warm front for several hours in the
afternoon.
.Marine...
Generally low winds and seas will prevail through mid-week until a
cold front passes through the northern Gulf increasing winds to
advisory levels temporarily on Wednesday. Low winds and seas will
return to finish out the week.
.Fire Weather...
With increased rain chances thru tonight, no red flag conditions are
expected and none is forecast through mid-next week.
.Hydrology...
There is a potential for heavy rainfall this afternoon with the
heaviest rain likely confined to north Florida, especially along
and west of the Apalachicola River. Widespread average totals will
be around 1-2 inches with isolated spots possibly receiving up to
3 to 5 inches. Flash flooding will likely not be a concern as
these basins should be able to accommodate the expected rainfall
amounts. In areas where heavy rainfall is expected, rivers may
reach minor flood stage Monday or Tuesday. The Apalachicola at
Blountstown is forecast to reach minor flood stage Sunday morning.
For the latest hydrology information, please monitor:
www.water.weather.gov/ahps2/index.php?wfo=tae
&&
.Preliminary Point Temps/PoPs...
Tallahassee 69 59 75 54 74 / 80 70 40 10 50
Panama City 67 60 70 57 69 / 80 70 40 20 50
Dothan 64 56 73 51 71 / 70 50 10 10 50
Albany 65 55 73 49 72 / 70 50 10 10 40
Valdosta 70 58 75 53 73 / 70 70 40 10 40
Cross City 73 60 75 57 75 / 50 70 40 10 50
Apalachicola 67 61 69 58 67 / 60 70 40 10 50
&&
.TAE Watches/Warnings/Advisories...
FL...None.
GA...None.
AL...None.
GM...None.
&&
$$
NEAR TERM...HARRIGAN
SHORT TERM...HARRIGAN
LONG TERM...WESTON
AVIATION...BLOCK
MARINE...HARRIGAN
FIRE WEATHER...BLOCK
HYDROLOGY...HARRIGAN/WESTON
Area Forecast Discussion
National Weather Service Lincoln IL
957 AM CST Sun Feb 23 2014
.DISCUSSION...
ISSUED 956 AM CST Sun Feb 23 2014
Lingering band of light snow in the southeast CWA has pushed into
Indiana. Radar mosaics still showing quite a few returns along the
I-70 corridor, but these are mostly elevated as surface obs are
showing cloud heights of 7000 feet or higher, so little more than
flurries anticipated the remainder of the morning. Persistent mid
level clouds continue to stream over the remainder of the forecast
area and should continue through the afternoon. Lowered
temperatures a couple degrees across the southeast CWA as they
had continued to slip downward as the snow began a few hours ago,
but the forecast over the remainder of the area still is in decent
shape.
Geelhart
&&
.AVIATION...
ISSUED 540 AM CST Sun Feb 23 2014
VFR conditions will prevail at all TAF sites next 24hrs. Mid
clouds around 9kft will overspread all sites this morning and
remain over the area/sites through the morning and into the
afternoon. Models indicate that the clouds will slide south away
from the TAF sites this afternoon, but satellite loop/trends show
clouds moving due east. So will keep at least BKN mid clouds over
the area into this evening. Then skies will clear around midnight.
Winds will be northerly to start and then shifts to northwesterly
as a high pressure ridge pushes into the area late this afternoon
and into the evening.
Auten
&&
.PREV DISCUSSION...
ISSUED 330 AM CST Sun Feb 23 2014
SHORT TERM...Today through Wednesday night
Surface cold front has pressed south of the Ohio River into NW AR
while 1042 mb arctic high pressure over Alberta was nosing into
the central and northern plains. Colder air easing south into
central IL early this morning with temps slipping through the 20s
over central IL and low to mid 30s in southeast IL. Temps as cold
as 19F at Galesburg and Lacon. Frontogenetic forecasting close to
850 mb boundary near I-70 had band of light snow that diminished
east into central IN past few hours with dusting to as much as 1
inch between I-72 and I-70. Will carry just slight chance of light
snow this morning over southeast IL per HRRR model run. Radar
mosaic shows light pcpn returns and mainly virga over northern MO
into NW counties. RUC & HRRR keeps most of this very light snow
west of central IL this morning but could be a few flurries this
morning into central IL. Clouds to decrease from the north during
the afternoon and linger longest in southeast IL. Much colder
highs today range from mid 20s from Peoria and Bloomington north
to 35-40F over southeast IL with Lawrenceville near 40F.
Arctic high pressure noses into the mid MS river valley tonight
and brings fair skies and cold lows of 5-10F from Lincoln north
and mid to upper teens in southeast IL. Clouds increase Monday
morning ahead of northern stream clipper system which digs into
the Midwest Monday night. Slowed down chances of light snow Monday
afternoon as central IL appear dry through sunset Monday with best
chances of light snow arriving Monday night northern half of CWA.
Generally less than 1 inch of snow with northern IL having as much
as 1-2 inches of snow possible. Highs Monday again in mid 20s
north and mid to upper 30s in southeast IL. Lows Monday night in
the teens central IL and lower 20s southeast IL. Chances of light
snow NE of central IL by Tuesday morning. Highs Tue range from
lower 20s northern areas to mid 30s in southeast IL.
Core of arctic high pressure settles into MO by 18Z/noon Wed and
brings even colder air into the region during middle of the week.
Lows overnight Tue night into early Wed morning could reach zero
to 5 below NW of IL river with single digit lows over much of
central IL and far southeast IL around 10F. Highs Wed in the mid
teens NE to lower 20s SW and SE areas. Lows Wed night again in the
single digits over northern half of CWA and lower teens south.
LONG TERM...Thursday through Saturday night
Temps modify slightly during end of week but still average below
normal through next weekend. The 8-14 day outlook for Mar 2-8 has
60-70% chance of below normal temperatures and 40% chance of above
normal precipitation, which has been the normal for this winter.
Generally dry and cold conditions expected late this week into
next weekend. Though ECMWF and GEM models show some light QPF
Friday while heavier QPF passes south of IL Friday. GFS model is
dry over IL on Friday. Stayed close to ALLblend pops late this
week and into the weekend which is dry.
07
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
543 AM CST SUN FEB 23 2014
.DISCUSSION...
213 AM CST
TODAY...
BROAD SFC RIDGE STRETCHES FROM THE NORTHERN PLAINS SOUTHEAST
THROUGH THE WESTERN OHIO VALLEY. THIS HAS RESULTED IN A LIGHT
NORTHWEST FLOW ACROSS NORTHERN IL/NORTHWEST IN EARLY THIS MORNING.
BAROCLINIC ZONE REMAINS ORIENTED FROM CENTRAL MO STRETCHING
NORTHEAST THROUGH CENTRAL IL/IN AND DRIFTING SOUTHEAST. IR IMAGERY
SHOWS THE AREA OF CLOUDS WELL...ASSOCIATED WITH THIS BAND OF
PRECIP. THEN JUST WEST OF THIS FEATURE WAS YET ANOTHER WEAK MID-
LVL WAVE THAT HAD ANOTHER AREA OF MID/UPR LVL MOISTURE ASSOCIATED
WITH IT AND WAS SLIDING EAST...BEING STEERED BY THE SEMI-ZONAL
FLOW IN THE MID-LVLS.
TEMPS THIS MORNING WILL HOVER AROUND THE TEENS FOR THE BULK OF THE
FORECAST AREA...PERHAPS HOLDING IN UPR TEENS/LOW 20S FOR THE
SOUTHERN CWFA. OTHERWISE FOR TODAY HIGH PRESSURE WILL PUSH THIS AREA
OF CLOUDS THIS MORNING TO THE SOUTH...AND ALLOW FOR A DRY DAY. SKIES
WILL EVENTUALLY BECOME P-CLOUDY BY MIDDAY...WITH HIGHS WARMING
MAINLY INTO THE 20S. CLOSER TO 30 FOR THE FAR SOUTHERN CWFA.
THEN FOR TONIGHT...HIGH PRESSURE WILL CONTINUE TO HOLD ACROSS THE
FORECAST AREA AND LIMIT CLOUD COVER. JUST NORTH OF THE AREA
THOUGH...AND CLOSER TO A STRONGER MID-LVL VORT WILL BE THICKER CLOUD
COVER. WINDS WILL GENERALLY REMAIN LIGHT FROM THE NORTHWEST...WHICH
COUPLED WITH 850MB TEMPS HOVERING ARND -10 TO -12 DEG C SHOULD LIMIT
HOW COOL TEMPS RADIATE OVERNIGHT. SO HAVE ONLY NUDGED TEMPS DOWN A
LITTLE...GENERALLY IN THE SINGLE DIGITS ABOVE ZERO. COULD SEE SOME
OF THE TRADITIONALLY COOLER LOCATIONS DIP TO ARND ZERO BY DAYBREAK
MON.
CONFIDENCE...HIGH.
MONDAY THROUGH TUESDAY...
500MB TROUGH AXIS OVER THE GREAT LAKES REGION PUSHES EAST...WITH AN
AREA OF WEAK RIDGING ARRIVING MIDDAY MON OVER THE FORECAST AREA.
HOWEVER GIVEN THE SEMI-ZONAL FLOW...WHICH IS GENERALLY A MORE
PROGRESSIVE SETUP...THE NEXT WAVE CONTINUES TO BE PROGGED FOR
ARRIVAL MON LATE AFTN/EVE. LATEST FORECAST GUIDANCE HAS CONTINUED TO
SUGGEST THE MID-LVL HEIGHT RISES MAY BE A LITTLE SLOWER TO DEPART
THE REGION...WHICH WOULD LIKELY HAVE AN INFLUENCE ON THE WEAK WAVE
ARRIVING POSSIBLY LATER. THE MAIN TIMING DOES APPEAR TO BE
CONSISTENT WITH JUST AFT 00Z TUE...AND GIVEN THE PREV-DISCUSSED
PROGRESSIVE FLOW...SKIES WILL THICKEN RATHER QUICKLY AND CIGS WILL
LOWER WITH EASE. LOCAL MODEL INDICATES A SLIGHTLY LATER ARRIVAL AND
CLOSER TO 6Z TUE...BUT ALSO IS INDICATING THE WAVE WILL BE WEAKENING
UPON ARRIVAL. CONFIDENCE ON THIS WAVE WEAKENING AS IT ARRIVES IS
VERY LOW...GIVEN THE DECENT MID-LVL FORCING ASSOCIATED. TEMPS
CONTINUE TO BE COOL ENOUGH TO SUPPORT LGT SNOW FOR THE AREA...AND
EXPECT SLR ARND 15:1 TO 18:1. THIS WILL LIKELY PRODUCE A QUICK 1 TO
2 INCHES OF SNOWFALL ACROSS MOST OF THE CWFA. BY 12-15Z TUE...THE
BULK OF THE WAVE/SNOW WILL BE PUSHING EAST AND COMING TO AN END.
THEN FOR TUE...500MB TROUGH AXIS ARRIVES AS AN ARCTIC AIRMASS
CONTINUES TO PUSH SOUTH FROM CANADA TOWARDS THE UPPER MIDWEST TUE
AFTN. CURRENTLY EXPECT HIGHS TUE TO HOLD IN THE TEENS/LOW
20S...HOWEVER BY TUE NGT THE BOUNDARY WILL BE PUSHING ACROSS THE
FORECAST AREA AND TEMPS WILL BE DROPPING TO A FEW DEGREES BELOW
ZERO.
CONFIDENCE...HIGH.
CONFIDENCE IN SNOW ACCUMS MON EVE/OVERNIGHT...HIGH.
WEDNESDAY THROUGH SUNDAY...
ENSEMBLES AND OPERATIONAL SOLUTIONS HAVE CONTINUED TO BE IN GOOD
AGREEMENT WITH THE ARRIVAL OF YET ANOTHER ARCTIC AIRMASS. BY WED THE
500MB TROUGH AXIS WILL BE OVERHEAD. CURRENT PROGS INDICATE TEMPS IN
MID-LVLS WILL HOVER ARND -20 TO -25 DEG C. WHEN APPLYING THIS
TOWARDS LOCAL CLIMATE WHICH LIKELY YIELD HIGH TEMPS WED IN THE
SINGLE DIGITS ABOVE ZERO TO POSSIBLY THE LOW TEENS. SFC RIDGE WILL
BE SLIDING OVER THE AREA AS WELL...WHICH SHOULD LIMIT HOW MUCH LOWER
WIND CHILL VALUES WILL BE WED. THEN FOR WED NGT...FLOW GRADUALLY
TURNS WESTERLY IN THE LLVLS. A WEAK SHORTWAVE IS PROGGED TO CLIP THE
NORTHERN GREAT LAKES REGION...HOWEVER EXPECT GENERALLY DRY WEATHER
FOR THE FORECAST AREA WED/WED NGT.
FOR THE REMAINDER OF THE EXTENDED PERIODS...ENSEMBLES REMAIN IN
DECENT AGREEMENT WITH YET ANOTHER SFC RIDGE SLIDING SOUTHEAST FROM
CENTRAL CANADA TOWARDS THE PLAINS AND STRETCHING EAST TO THE WESTERN
GREAT LAKES THUR. THIS SHOULD HELP TO MAINTAIN UNSEASONABLY COLD
CONDS FOR THE FORECAST AREA...WITH TEMPS STRUGGLING TO WARM BEYOND
THE LOW/MID TEENS THUR AFTN.
STRONG VORTEX BEGINS TO LIFT NORTHEAST THUR NGT/FRI...WITH SOME
MODERATION TO TEMPS POISED FOR THE END OF THE WEEK INTO THE FIRST
HALF OF NEXT WEEKEND. ALTHOUGH THIS IS RELATIVE...AS TEMPS WILL
CONTINUE TO BE UNSEASONABLY COOL IN THE TEENS/LOW 20S. GUIDANCE IS
SUGGESTING THE SOUTHERN STREAM WILL BECOME ACTIVE YET AGAIN IN THE
LATER PERIODS...AND INDICATES THE PRECIP WILL REMAIN SOUTH OF THE
CWFA. ALTHOUGH COULD SEE SOME ADJUSTMENTS TO THE PLACEMENT OF EACH
SOUTHERN STREAM WAVE.
CONFIDENCE...MEDIUM/HIGH.
BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 12Z...
* NONE
//DISCUSSION...UPDATED 12Z...
A RIDGE OF HIGH PRESSURE EXTENDS FROM THE NORTHERN PLAINS INTO
CENTRAL ILLINOIS EARLY THIS MORNING AND WILL REMAIN RELATIVELY
STATIONARY THROUGH THE FORECAST PERIOD PROVIDING QUIET WEATHER WITH
VFR CONDITIONS AND WNW WINDS. A FEW GUSTS INTO THE HIGH TEENS TO
AROUND 20 KT ARE POSSIBLE THIS AFTERNOON AND EARLY EVENING...THEN
SHOULD TAPER MID TO LATE IN THE EVENING. THE NEXT CHANCE FOR ANY
SIGNIFICANT WEATHER IMPACTS APPEARS TO BE MONDAY NIGHT INTO TUESDAY
WHEN SNOW WILL MOVE ACROSS THE AREA WITH LIGHT ACCUMULATIONS
POSSIBLE.
//ORD AND MDW CONFIDENCE...UPDATED 12Z...
* HIGH
BMD
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
MONDAY NIGHT...SNOW LIKELY WITH LIGHT ACCUMULATIONS POSSIBLE.
TUESDAY THROUGH SATURDAY...VFR LIKELY.
BMD
&&
.MARINE...
302 AM CST
MODERATE WEST TO NORTHWEST WINDS ARE EXPECTED TO CONTINUE THROUGH
THE REMAINDER OF THE WEEKEND AND INTO THE MIDDLE OF NEXT WEEK ACROSS
LAKE MICHIGAN ON THE EASTERN PERIPHERY OF A STRONG RIDGE THAT
EXTENDS FROM THE CANADIAN ROCKIES INTO THE OHIO VALLEY. WINDS WILL
GENERALLY BE IN THE 20 TO 30 KT RANGE THROUGH TUESDAY...THEN A
SERIES OF LOWS WILL DROP FROM CANADA INTO THE GREAT LAKES
REGION...THE STRONGEST OF WHICH WILL BE WEDNESDAY NIGHT. A SURGE OF
ARCTIC AIR WILL OVERSPREAD THE WESTERN LAKES BEHIND THIS LOW AND A
PERIOD OF NORTHWESTERLY GALES IS POSSIBLE...ALONG WITH FREEZING
SPRAY. THE RIDGE WILL START TO BUILD CLOSER TO LAKE MICHIGAN LATER
IN THE WEEK AND INTO THE WEEKEND WITH WINDS DIMINISHING.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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Area Forecast Discussion
National Weather Service Lincoln IL
540 AM CST Sun Feb 23 2014
.DISCUSSION...
ISSUED 330 AM CST Sun Feb 23 2014
SHORT TERM...Today through Wednesday night
Surface cold front has pressed south of the Ohio River into nw AR
while 1042 mb arctic high pressure over Alberta was nosing into
the central and northern plains. Colder air easing south into
central IL early this morning with temps slipping through the 20s
over central IL and low to mid 30s in southeast IL. Temps as cold
as 19F at Galesburg and Lacon. Frontogenetic forecasting close to
850 mb boundary near I-70 had band of light snow that diminished
east into central IN past few hours with dusting to as much as 1
inch between I-72 and I-70. Will carry just slight chance of light
snow this morning over southeast IL per HRRR model run. Radar
mosaic shows light pcpn returns and mainly virga over northern MO
into nw counties. RUC & HRRR keeps most of this very light snow
west of central IL this morning but could be a few flurries this
morning into central IL. Clouds to decrease from the north during
the afternoon and linger longest in southeast IL. Much colder
highs today range from mid 20s from Peoria and Bloomington north
to 35-40F over southeast IL with Lawrenceville near 40F.
Arctic high pressure noses into the mid MS river valley tonight
and brings fair skies and cold lows of 5-10F from Lincoln north
and mid to upper teens in southeast IL. Clouds increase Monday
morning ahead of northern stream clipper system which digs into
the Midwest Monday night. Slowed down chances of light snow Monday
afternoon as central IL appear dry through sunset Monday with best
chances of light snow arriving Monday night northern half of CWA.
Generally less than 1 inch of snow with northern IL having as much
as 1-2 inches of snow possible. Highs Monday again in mid 20s
north and mid to upper 30s in southeast IL. Lows Monday night in
the teens central IL and lower 20s southeast IL. Chances of light
snow ne of central IL by Tuesday morning. Highs Tue range from
lower 20s northern areas to mid 30s in southeast IL.
Core of arctic high pressure settles into MO by 18Z/noon Wed and
brings even colder air into the region during middle of the week.
Lows overnight Tue night into early Wed morning could reach zero
to 5 below nw of IL river with single digit lows over much of
central IL and far southeast IL around 10F. Highs Wed in the mid
teens ne to lower 20s sw and se areas. Lows Wed night again in the
single digits over northern half of CWA and lower teens south.
LONG TERM...Thursday through Saturday night
Temps modify slightly during end of week but still average below
normal through next weekend. The 8-14 day outlook for Mar 2-8 has
60-70% chance of below normal temperatures and 40% chance of above
normal precipitation, which has been the normal for this winter.
Generally dry and cold conditions expected late this week into
next weekend. Though ECMWF and GEM models show some light qpf
Friday while heavier qpf passes south of IL Friday. GFS model is
dry over IL on Friday. Stayed close to ALLblend pops late this
week and into the weekend which is dry.
07
&&
.AVIATION...
ISSUED 540 AM CST Sun Feb 23 2014
VFR conditions will prevail at all TAF sites next 24hrs. Mid
clouds around 9kft will overspread all sites this morning and
remain over the area/sites through the morning and into the
afternoon. Models indicate that the clouds will slide south away
from the TAF sites this afternoon, but satellite loop/trends show
clouds moving due east. So will keep at least BKN mid clouds over
the area into this evening. Then skies will clear around midnight.
Winds will be northerly to start and then shifts to northwesterly
as a high pressure ridge pushes into the area late this afternoon
and into the evening.
Auten
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
528 AM CST SUN FEB 23 2014
.UPDATE...
ISSUED AT 516 AM CST SUN FEB 23 2014
RADAR TRENDS THE PAST SEVERAL HOURS SHOW A SLOW WEAKENING OF
RETURNS ACROSS NORTHERN MISSOURI. KSTJ AND KCNK HAVE BEEN THE ONLY
OBSERVATION SITES THAT HAVE REPORTED ANY SNOW. RAP MODEL TRENDS
CONTINUE TO SHOW A SUBSTANTIAL DRY LAYER BELOW 850MB IN THE
FORECAST SOUNDINGS.
A COUPLE OF FLURRIES CANNOT BE RULED OUT SOUTH OF A KTVK TO KMQB
LINE EARLY THIS MORNING. BASED ON RADAR TRENDS...A DRY FORECAST
STILL LOOKS REASONABLE.
&&
.SYNOPSIS...
ISSUED AT 300 AM CST SUN FEB 23 2014
06Z SFC ANALYSIS HAS A FRONTAL BOUNDARY FROM THE OHIO VALLEY INTO
THE SOUTHERN PLAINS. A WEAK TROF RAN THROUGH THE GREAT LAKES WHILE
HIGH PRESSURE WAS OVER THE NORTHERN PLAINS. DEW POINTS WERE IN THE
SINGLE DIGITS AND TEENS FROM THE NORTHERN PLAINS INTO THE UPPER
MIDWEST WITH 20S AND 30S FROM THE SOUTHERN GREAT LAKES AND OHIO
VALLEY INTO THE REMAINDER OF THE PLAINS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 300 AM CST SUN FEB 23 2014
THE NEXT WEAK DISTURBANCE ALOFT IS MOVING FROM THE PLAINS INTO THE
LOWER MISSOURI VALLEY. ALTHOUGH RADAR RETURNS LOOK IMPRESSIVE...NO
REPORTING STATION INDICATES PRECIPITATION REACHING THE GROUND.
FORECAST SOUNDINGS INDICATE A VERY DRY ATMOSPHERE WILL REMAIN IN
PLACE ACROSS THE AREA TODAY AND TONIGHT AS HIGH PRESSURE SLOWLY
BUILDS INTO THE MIDWEST.
AT THE VERY WORST A FEW FLURRIES MIGHT BE SEEN ACROSS THE EXTREME
SOUTHERN AREAS EARLY THIS MORNING. OTHERWISE DRY CONDITIONS WILL BE
SEEN ACROSS THE AREA TODAY AND TONIGHT. TEMPERATURES WILL AVERAGE
BELOW NORMAL.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 300 AM CST SUN FEB 23 2014
CONTINUED VERY COLD WITH NEAR RECORD LOW TEMPERATURES WITH LIGHT
SNOW LIKELY MANY AREAS ON MONDAY.
OVERVIEW...LITTLE SENSIBLE WEATHER ISSUES BESIDES LIGHT SNOW AND
FLURRIES WITH NEXT INFUSION OF ARCTIC AIR ARRIVING ON MONDAY. LOW
LEVEL THERMAL AND MOISTURE FIELDS SUGGESTS A 70/30 MIX OF HI-RES
ECMWF WITH GFS. DEEP NW CYCLONIC FLOW KEEPS ARCTIC AIR IN PLACE
DAYS 2 THROUGH 7 WITH LITTLE SENSIBLE WEATHER ISSUES. LOW LEVEL
THERMAL FIELDS SUPPORT NEAR RECORD TO RECORD LOW MINS WEDNESDAY AM
AND POSSIBLY AGAIN TOWARD FRIDAY DEPENDING ON HIGH PRESSURE TRACKS.
MONDAY...UPPED POPS TO LIKELY...MOSTLY MONDAY EVENING WITH CENTRAL
1/3 OR MORE OF FORECAST AREA TO RECEIVE 2 TO 3 HOURS OF LIGHT SNOW
AS WEAK DISTURBANCE PASSES. LOCAL TOOLS AND TECHNIQUES SUGGEST .5
TO LOCALLY NEAR 1 INCH OF A POWDERY DRY SNOW WITH LWE OF 20:1 OR MORE.
FAR NORTH AND SOUTH SECTIONS MAY RECEIVE MORE OF A DUSTING OF FLURRIES.
TEMPERATURES IN THE TEENS NORTH TO MID/UPPER 20S FAR SOUTH SECTIONS.
MONDAY NIGHT...LOWS AS A CHALLENGE AS CLEARING SHOULD OCCUR AFTER
MIDNIGHT NW TO NEAR DAYBREAK SE SECTIONS. HENCE...MINS NEAR ZERO ARE
SUGGESTED TO MID TEENS SE SECTIONS. LATER SHIFTS MAY NEED TO CHANGE
THESE VALUES BY 5+ DEGREES IF CLEARING IS EARLIER OR DELAYED.
TUESDAY...MUCH COLDER AIR TO RESULT IN NEARLY STEADY TEMPERATURES
WITH NW WINDS OF 10 TO 20 MPH TO KEEP WIND CHILLS IN SINGLE DIGITS
SE TO NEGATIVE SINGLE DIGITS NW SECTIONS DESPITE FAIR SKIES. TUESDAY
NIGHT...WINDS TO BECOME NEARLY CALM TOWARD DAYBREAK WITH STRONG AND
SHALLOW INVERSION. LOWS SHOULD BE NEAR OR BREAK RECORDS AS DESCRIBED
IN CLIMATE SECTION BELOW. THIS SUPPORTS -13 TO +4 SE WITH FAVORED
LOCATIONS MAY NEED TO TRIMMED EVEN FURTHER BY 2 TO 5 DEGREES IF
SEVERAL HOURS OF CALM TO NEARLY CALM WINDS AND CLEAR SKIES OCCUR.
THIS MAY RESULT IN WIND CHILLS WELL BELOW -20 DEGREES INTO LATE
MORNING.
WEDNESDAY THROUGH SATURDAY...CONTINUED QUITE COLD AND FAIR TO MOSTLY
FAIR AND GENERALLY DRY WITH LOWS WELL BELOW NORMAL BY 15 TO 20 DEGREES.
THIS SUPPORTS HIGHS MOSTLY IN THE TEENS WITH SOME UPPER SINGLE DIGITS
POSSIBLE NORTH AND LOWS SINGLE DIGITS AND POSSIBLY WELL INTO THE NEGATIVE
SINGLE DIGITS NORTH SECTIONS. NEXT WAVE OFF CALIFORNIA MAY REQUIRE
ADDING SNOW FRIDAY NIGHT AND ESPECIALLY SATURDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 516 AM CST SUN FEB 23 2014
VFR CONDITIONS WILL BE SEEN THROUGH 12Z/24 AS A WEAK DISTURBANCE
MOVES ACROSS MISSOURI AND HIGH PRESSURE BUILDS SOUTH FROM CANADA.
&&
.CLIMATE...
ISSUED AT 300 AM CST SUN FEB 23 2014
RECORD LOWS FOR FEBRUARY 26...
MOLINE.........-14 IN 1963
CEDAR RAPIDS...-08 IN 1950
DUBUQUE........-10 IN 1980
BURLINGTON.....-11 IN 1950
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...08
SYNOPSIS...08
SHORT TERM...08
LONG TERM...NICHOLS
AVIATION...08
CLIMATE...NICHOLS
AREA FORECAST DISCUSSION
NWS GOODLAND KS
850 AM MST SUN FEB 23 2014
.UPDATE...
ISSUED AT 850 AM MST SUN FEB 23 2014
ENTIRE FORECAST AREA ENTRENCHED IN STRATUS THIS MORNING WITH
EAST/NORTHEAST WINDS EAST OF THE CO/KS BORDER AND SOUTHEAST WINDS
ACROSS FAR EASTERN COLORADO. FOG ALSO BEING REPORTED ACROSS THE
WESTERN 2/3 OF THE AREA WITH LOCALLY DENSE FOG IN THE GOODLAND
AREA.
LATEST RUC HAS AN EXCELLENT GRASP OF THE STRATUS AND PER THE 12Z
RUN KEEPS IT OVER THE AREA FOR THE ENTIRE DAY. THE HRRR BREAKS UP
THE STRATUS OVER PARTS OF FAR EASTERN COLORADO BUT KEEPS IT OVER
THE REST OF THE AREA THROUGH THE DAY AS WELL. SHOULD THESE
SCENARIOS VERIFY TEMPERATURES WONT MOVE MUCH FROM WHERE THEY ARE
NOW AND WOULD BE SEVERAL DEGREES BELOW PREVIOUS FORECAST.
12Z NAM BOUNDARY LAYER RH ALSO HAD A GOOD HANDLE ON AREAL COVERAGE
OF STRATUS BUT BY 18Z LIFTS IT/DISSIPATES IT FROM SOUTH TO NORTH
ALLOWING MORE HEATING AND WARMER TEMPERATURES THAN THE RUC/HRRR.
FOR THE FIRST OF WHAT WILL LIKELY BE SEVERAL UPDATES HAVE TRENDED
TOWARD THE RUC/HRRR GIVEN THE EASTERLY COMPONENT TO THE WINDS ALL
DAY WHICH ISNT REAL FAVORABLE FOR RAPID STRATUS DISSIPATION AS THE
NAM WOULD SUGGEST. HAVE LOWERED HIGH TEMPERATURES TO THE MID/UPPER
20S ACROSS THE NORTHEAST AND EAST (WHERE LOW CLOUDS EXPECTED
LONGER) AND LOW TO MID 30S ACROSS THE FAR SOUTH THROUGH SOUTHWEST
AND WEST WHERE SOME DISSIPATION WOULD BE MOST LIKELY BUT NOT
CERTAIN AT THIS POINT.
HAVE ALSO BEEFED UP THE FOG PER LOCAL OBSERVATIONS. NONE OF THE
MODELS HANDLING THIS VERY WELL...HOPEFULLY THE 15Z RUC WILL LATCH
ON TO IT AND GIVE SOME BETTER GUIDANCE.
MORE UPDATES LIKELY TO COME LATER.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY NIGHT)
ISSUED AT 314 AM MST SUN FEB 23 2014
UPPER FLOW WILL BE NORTHWEST THROUGH TUESDAY NIGHT. SURFACE HIGH
PRESSURE WILL BE OVER THE REGION TODAY AND TONIGHT. HIGH PRESSURE
WILL DRIFT EAST MONDAY AS LOW PRESSURE MOVES INTO EASTERN COLORADO.
A COLD FRONT WILL PUSH SOUTH MONDAY NIGHT FOLLOWED BY HIGH PRESSURE
TUESDAY AND TUESDAY NIGHT.
CURRENT RADAR SHOWING DECREASING TREND OF SNOW RETURNS OVER THE
NORTH IN THE CURRENT WINTER WEATHER ADVISORY. FRONTOGENESIS EXITS
THE AREA AND DO NOT EXPECT ANYTHING MORE THAN LIGHT SNOW THIS
MORNING AND EVEN LESS OF AN AREA THIS AFTERNOON AS DYNAMICS MOVE OUT
OF THE AREA. PLAN TO CANCEL THE WINTER WEATHER ADVISORY AT ZONES
ISSUANCE. DEWPOINT DEPRESSIONS ARE NARROWING TO LESS THAN 3 DEGREES
AND BOUNDARY LAYER RH IS PROGGED TO INCREASE TO OVER 90 PERCENT SO
HAVE INCLUDED SOME PATCHY FREEZING FOG THIS MORNING OVER ALL BUT THE
NORTHEAST FA.
FORECAST SOUNDINGS ACROSS THE FA TONIGHT INDICATE THE POSSIBILITY OF
SOME STRATUS AND FOG BUT MOISTURE IS TOO SHALLOW TO INDICATE
FREEZING DRIZZLE. PLAN TO PULL THE FREEZING DRIZZLE AND CONSIDER
SOME MENTION OF FOG OVERNIGHT INTO MONDAY MORNING. POPS WILL BE NIL
MONDAY DUE TO SUBSIDENCE AND LACK OF MOISTURE. THERE IS SOME WEAK
FORCING ACROSS THE NORTHERN ZONES MONDAY NIGHT/TUESDAY MORNING AND
MOISTURE INCREASES SO CANNOT RULE OUT A SLIGHT CHANCE OF LIGHT SNOW
OR FLURRIES. FOR TUESDAY AFTERNOON/TUESDAY NIGHT...THE GFS IS FASTER
WITH BRINGING DYNAMICS INTO THE FA THAN THE NAM. FOR NOW WILL OPT FOR
THE GFS TO STAY CONSISTENT WITH SURROUNDING OFFICES. HOWEVER DUE TO
THE TIMING DIFFERENCES WILL KEEP POPS IN THE SLIGHT CHANCE/CHANCE
RANGE.
MAX TEMPERATURES TODAY WILL BE IN THE MID 30S EXCEPT FOR WESTERN
PORTIONS OF EASTERN COLORADO WHERE SOME LOWER 40S WILL BE POSSIBLE.
TEMPERATURES WILL WARM INTO THE 40S WITH SOME MID 50S POSSIBLE IN
THE SOUTHWEST PORTION OF THE FA. TUESDAY WILL BE COLDER BEHIND THE
FRONT WITH READINGS IN THE UPPER 20S AND LOW 30S. MIN TEMPERATURES
TONIGHT WILL FALL INTO THE LOWER 20S AND INTO THE TEENS MONDAY AND
TUESDAY NIGHTS.
.LONG TERM...(WEDNESDAY THROUGH SATURDAY)
ISSUED AT 236 AM MST SUN FEB 23 2014
A RETURN OF BELOW NORMAL TEMPERATURES WILL BE THE MAIN
CHARACTERISTIC OF THE EXTENDED FORECAST WITH A FEW PERIODS OF SNOW
POSSIBLE. MODELS INDICATE THAT NORTHWEST FLOW IS THE PRIMARY UPPER
LEVEL PATTERN ACROSS THE TRI-STATE AREA WITH A LARGE TROUGH OVER THE
EASTERN UNITED STATES AND A RIDGE TO THE WEST. WITH THIS PATTERN IN
PLACE...THE GATE IS OPEN FOR COLD CANADIAN AIR TO MOVE IN. THIS PATTERN
IS SIMILAR TO THE EXTENDED VERY COLD OUTBREAK OBSERVED EARLIER THIS
MONTH. THE COLD WEATHER IS NOT EXPECTED TO REACH THAT EXTENT AGAIN
BUT WELL BELOW NORMAL TEMPERATURES SHOULD BE EXPECTED. THE FORECAST
INITIALIZATION PROCEDURE PROVIDED TEMPERATURES THAT SEEMED
UNREASONABLY WARM FOR THIS TYPE OF PATTERN. THE EUROPEAN SEEMS MOST
REASONABLE AND IS SUPPORTED BY THE CANADIAN MODEL. THE OPERATIONAL
GFS HAS 850 MB TEMPS IN THE SAME BALLPARK AS THE EUROPEAN HOWEVER
MEX GUIDANCE IS 10 TO NEARLY 20 DEGREES WARMER FOR FRIDAY AND
SATURDAY. AS A RESULT...TEMPERATURES WERE NUDGED DOWN A FEW DEGREES
BUT FORECAST IS STILL PROBABLY TOO WARM.
AS FOR PRECIPITATION...THERE ARE TWO CHANCES AT WINTRY PRECIP DURING
THE EXTENDED PERIOD. FOR WEDNESDAY...THE UPPER LEVEL DISTURBANCE
THAT WILL BRING SNOW FOR TUESDAY NIGHT SHOULD BE CLEAR OF THE REGION
WITH HIGH PRESSURE BUILDING IN. ADVERTISED DRY CONDITIONS FOR
WEDNESDAY BUT A FEW FLURRIES MAY LINGER DEPENDING ON SPEED AND
MOVEMENT OF THIS SYSTEM. THE FIRST CHANCE FOR PRECIPITATION IN THE
EXTENDED FORECAST IS ANTICIPATED ON THURSDAY NIGHT INTO FRIDAY. THIS
CHANCE COMES AS A STRONGER DISTURBANCE IN THE NORTHWEST FLOW
TRANSITIONS ACROSS THE REGION. MODELS DISAGREE SOMEWHAT IN THE
PLACEMENT AND MOVEMENT OF THIS SYSTEM SO HAVE ONLY GONE SLIGHT
CHANCE TO LOW CHANCE POPS FOR THURSDAY NIGHT. DUE TO THE SPEED OF
THIS SYSTEM...AN EXTENDED PERIOD OF ACCUMULATING SNOW IS NOT
EXPECTED. IT IS ALSO POSSIBLE THIS SYSTEM MOVES SOUTH OF THE AREA
WITH NO SNOW AS THE BEST FORCING APPEARS TO REMAIN SOUTH.
THE SECOND...MORE SIGNIFICANT CHANCE OF PRECIPITATION COMES FOR NEXT
WEEKEND. THROUGH 00Z SATURDAY...THE EUROPEAN...CANADIAN AND GFS
MODELS ARE IN DECENT AGREEMENT ON A 500 MB LOW COMING INTO
CALIFORNIA. THE GFS AND EUROPEAN MODELS THEN BRING THIS SYSTEM
ACROSS THE ROCKIES ON SATURDAY AND INTO THE HIGH PLAINS SUNDAY. THESE
TYPES OF SYSTEMS ARE TYPICALLY RESPONSIBLE FOR LARGER SNOW AMOUNTS
SO WILL NEED TO MONITOR THIS SYSTEM CLOSELY. AS WITH ANY EXTENDED
FORECAST...MODELS CAN AND OFTEN DO CHANGE THEIR SOLUTIONS THIS FAR
OUT. HOWEVER...WITH BOTH MODELS PICKING UP ON IT AND PROJECTING A
SIMILAR SOLUTION...THIS MAY HAVE A LITTLE MORE WEIGHT TO IT THAN A
TYPICAL EXTENDED FORECAST STORM.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 438 AM MST SUN FEB 23 2014
SOME IFR AND LIFR CONDITIONS WILL CONTINUE THIS MORNING AT KGLD AND KMCK
BEHIND AN EXITING SHORTWAVE. CONDITIONS SHOULD IMPROVE TO MVFR AT
KGLD THIS AFTERNOON BUT WILL DROP BACK DOWN TO IFR TONIGHT AS FOG
AND STRATUS OVERTAKE THE AREA.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...99
SHORT TERM...FS
LONG TERM...RRH
AVIATION...FS
AREA FORECAST DISCUSSION....CORRECTED
NWS JACKSON MS
400 AM CST SUN FEB 23 2014
.SHORT TERM...TODAY THROUGH MONDAY NIGHT...LOW LEVEL WARM/MOIST
ADVECTION IS UNDERWAY ALONG THE GULF COAST THIS MORNING EVIDENT BY
INCREASING COVERAGE OF SHOWER AND THUNDERSTORM ACTIVITY ACROSS
EASTERN LA/SOUTHERN MS. FURTHER NORTH...AN ADVANCING COLD FRONT IS
ANALYZED ON THE NORTHERN FRINGES OF THE TN VALLEY WHICH IS PROGGED
TO CROSS THE ARKLAMISS STARTING LATE THIS AFTERNOON. PRIMARY CONCERN
FOR TODAY IS THE RISK FOR HEAVY RAINS ALONG THE HWY 98
CORRIDOR...AND THUNDERSTORMS THAT COULD PRODUCE SOME NICKEL TO
QUARTER SIZE HAIL ALONG AND SOUTH OF HWY 84. 00Z NMM/ARW/LOCAL WRF
OUTPUT SHOW THE AFOREMENTIONED SHOWER/THUNDER ACTIVITY EXPANDING
INTO SOUTHERN ZONES BY MID MORNING AND GRADUALLY COMING TO AN END BY
LATE AFTERNOON/EARLY EVENING.
THE GUIDANCE HAS BEEN CONSISTENT SHOWING MID LEVEL LAPSE RATES
CLIMBING INTO THE 6.5-7.5C/KM RANGE SOUTH OF I-20 AS THE LOW LEVEL
WARM AIR SURGES IN...WITH SHOWALTER INDICES IN THE -2 TO -4C RANGE
INDICATIVE OF ELEVATED CONVECTION POTENTIAL GIVEN RELATIVELY COOL
PBL PER BUFR SOUNDINGS. WHILE LOW LEVEL WINDS LOOK TO VEER WESTERLY
BY DAYBREAK...A PASSING MID/UPPER LEVEL JET STREAK JUST TO OUR NORTH
WILL PROVIDE NEEDED ASCENT FOR CONVECTION AS THE RIGHT ENTRANCE
REGION OF THIS FEATURE PASSES. A FEW DEEPER THUNDERSTORM CORES SEEM
REASONABLE GIVEN THE SYNOPTIC SETUP AND WILL KEEP THE MENTION OF
SOME QUARTER SIZE HAIL IN THE HWO FOR TODAY.
OF EQUAL (IF NOT GREATER) CONCERN IS THE POTENTIAL FOR SOME LOCALLY
HIGH RAINFALL TOTALS ALONG HWY 98 COME LATE AFTERNOON. LOCAL WRF
OUTPUT SHOWS A SWATH OF 3-5 INCHES ACROSS MARION/LAMAR/FORREST
COUNTIES BETWEEN 12Z AND 22Z...WHILE THE HI-RES NMM/ARW SHOW
SIMILARLY ALARMING TOTALS OF ANYWHERE FROM 2-4 INCHES DURING THE
SAME TIME. GIVEN PW VALUES CLIMBING NEAR/JUST ABOVE 1.5 IN ACROSS
THIS AREA BY MID DAY (RIGHT AT THE 99TH PERCENTILE FOR FEB) AND THE
CONVECTIVE NATURE OF THE ACTIVITY THESE KINDS OF TOTALS SEEM QUITE
REASONABLE. THE BIGGEST QUESTION MARK IS JUST WHERE IS THE HEAVIEST
AXIS GOING TO SET UP. THE HRRR HAS BEEN TOYING WITH THE BEST AXIS
REMAINING CLOSER TO THE COAST ON A FEW RUNS...BUT SHOWS 2-3 IN
ALONG/SOUTH OF HWY 98 ON OTHERS. GIVEN THE HEAVY RAINS WE SAW ACROSS
THIS AREA A COUPLE DAYS AGO AND THE COINCIDENT HEAVY RAIN AXIS SHOWN
IN THE HI-RES ARW/NMM/LOCAL WRF FEEL THE RISK FOR FLASH FLOODING IS
GREAT ENOUGH TO WARRANT A FLASH FLOOD WATCH THROUGH 22Z. BY EARLY
EVENING THE BETTER FORCING WILL SHIFT EAST WHICH WILL SHUNT DEEPER
CONVECTION AND ASSOCIATED HEAVY RAIN RISK EAST AS WELL.
OTHER THAN SOME LIGHT SHOWER ACTIVITY SOUTH OF I-20 THE OVERNIGHT
HOURS LOOK PRETTY QUIET AS THE COLD FRONT CROSSES THE REGION. QUIET
CONDITIONS LOOK TO PREVAIL THROUGH MONDAY NIGHT...ALTHOUGH IT`S NOT
COMPLETELY OUT OF THE QUESTION THAT A FEW LIGHT SHOWERS COULD
DEVELOP ACROSS THE DELTA EARLY TUE MORNING AS A JET STREAK IN THE
PERSISTENT WESTERLY FLOW ALOFT NOSES IN. AS FOR TEMPS/POPS...LOWERED
MAV GUIDANCE FOR THIS AFTERNOON ACROSS SOUTHEASTERN AREAS GIVEN THE
HIGH CHANCES FOR RAIN/CLOUDS THROUGH THE DAY. ALSO RAISED OVERNIGHT
LOWS FOR TUE MORNING TOWARD THE WARMER NAM/ECMWF MOS NUMBERS AND RAW
GFS OUTPUT. POPS FOR TODAY WERE RAISED QUITE A BIT NEAR HBG. /BK/
.LONG TERM...TUESDAY THROUGH SUNDAY...BELOW NORMAL TEMPERATURES ARE
EXPECTED FOR THE WORK WEEK WITH NEAR NORMAL TEMPERATURES RETURNING
FOR THE WEEKEND. RAIN WILL SPREAD ACROSS THE CWA TUESDAY ASSOCIATED
WITH A SFC LOW OVER THE SOUTHERN PLAINS AND A COLD FRONT DROPPING
THROUGH THE REGION. THE ECMWF CONTINUES TO GENERATE MORE RAINFALL
THAN MODEL CONSENSUS WOULD SUGGEST OVER THE SOUTHERN PORTION OF OUR
CWA WHERE MORE THAN AN INCH TOTAL COULD FALL BY WEDNESDAY MORNING.
THE ARCTIC AIR WILL BE FILTERING INTO OUR CWA TUESDAY NIGHT AS THE
RAIN ENDS FROM THE NORTHWEST. THE LIGHT RAIN LOOKS TO MIX WITH OR
BRIEFLY CHANGE OVER TO LIGHT SNOW BEFORE ENDING EARLY WEDNESDAY
MORNING ALONG THE HIGHWAY 82 CORRIDOR. TEMPERATURES WILL REMAIN
ABOVE FREEZING AND BOTTOM OUT IN THE MID 30S ALONG THE HIGHWAY 82
CORRIDOR SO NO ACCUMULATION ON ROADWAYS IS CURRENTLY ANTICIPATED. NO
SIGNIFICANT PRECIPITATION IS EXPECTED AFTER SUNRISE WEDNESDAY. THE
STRONG CAA WILL HOLD HIGH TEMPERATURES IN THE 40S ACROSS MUCH OF THE
NORTHERN HALF OF THE AREA. THE ASSOCIATED SURFACE HIGH WILL BECOME
CENTERED OVER OUR CWA WEDNESDAY NIGHT AND THEN SHIFT EAST OF OUR CWA
THURSDAY AFTERNOON. THIS WILL SET UP THE COLDEST MORNING OF THE
FORECAST PERIOD THURSDAY MORNING WHERE LOWER 20S WILL BE COMMON IN
THE NORTH TO AROUND 30 DEGREES IN THE SOUTH. DRY WEATHER WILL
CONTINUE THURSDAY BUT A DISTURBANCE WILL DROP OVER THE SOUTHERN
PLAINS THURSDAY NIGHT AND HELP DEVELOP A SURFACE LOW. WAA AHEAD OF
THIS SYSTEM WILL BRING RAIN BACK INTO OUR WESTERN ZONES THURSDAY
NIGHT. THE ECMWF IS FASTER THAN THE GFS AND ENSEMBLES BUT CONSENSUS
BRINGS THE SHORTWAVE AND SFC LOW OVER OUR WESTERN ZONES BY FRIDAY
EVENING AND SHIFT THE SYSTEM EAST OF OUR CWA SATURDAY. DRY WEATHER
LOOKS TO RETURN SATURDAY AND LAST THROUGH MUCH OF SUNDAY. ANOTHER
DISTURBANCE WILL DROP OVER THE SOUTHERN PLAINS SUNDAY AND INCREASE
OUR RAIN CHANCES AGAIN SUNDAY NIGHT. /22/
&&
.AVIATION...MVFR CIG WL LIKELY IMPACT AREAS ALONG/S OF I-20 EARLY
THIS MORNING BEFORE VFR CIG TRY AND RETURN AFTER 15Z OR SO. ONLY
EXCEPTION MAY VERY WELL BE NEAR HBG/PIB WHERE PERSISTENT SHRA/TSRA
BRING AT LEAST INTERMITTENT MVFR/IFR CIG AND VSBY THRU MOST OF THE
DAYLIGHT HRS. THE HEAVY RAINS NEAR HBG/PIB WL COME TO AN END BY
EARLY EVENING AS THIS ACTIVITY PUSHES E. A COLD FRONT WL START
CROSSING THE ARKLAMISS FROM THE N AROUND 22Z PASSING THRU THE
PIB/HBG AREA AROUND 06-08Z TONIGHT. NLY WINDS WL BECOME A BIT GUSTY
IN WAKE OF THE FRONT...BUT LIGHTER WINDS WL RETURN DURING THE DAY
MON. /BK/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 73 46 60 48 / 31 13 0 5
MERIDIAN 74 47 63 46 / 35 13 0 6
VICKSBURG 73 44 58 47 / 26 11 0 5
HATTIESBURG 70 55 67 50 / 90 16 0 9
NATCHEZ 70 49 59 49 / 39 17 0 7
GREENVILLE 69 36 55 42 / 7 7 0 7
GREENWOOD 74 38 55 43 / 7 8 0 4
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...FLASH FLOOD WATCH THROUGH THIS AFTERNOON FOR MSZ072>074.
LA...NONE.
AR...NONE.
&&
$$
BK/22/BK
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
630 AM CST SUN FEB 23 2014
.UPDATE...
ISSUED AT 625 AM CST SUN FEB 23 2014
JUST GOT A REPORT OF 6 INCHES SNOWFALL IN OGALLALA. ADDITIONAL
SNOWFALL THIS MORNING WOULD LIKELY PUT THAT COUNTY IN THE 6 INCHES
IN 12 HOUR CRITERIA. AN ADDITIONAL 2 INCHES WOULD PUT THEM IN THE
8 INCHES IN 24 HOUR CRITERIA. A WARNING HAS BEEN ISSUED FOR THAT
COUNTY.
UPDATE ISSUED AT 538 AM CST SUN FEB 23 2014
THE METAR AT KOGA IS SHOWING 1 MILE VSBY WITH MODERATE SNOW. THE
NEDOR CAMS IN DEUEL COUNTY SHOW SIGNIFICANT ON THE GROUND AND
STILL FALLING AS THE SECOND DISTURBANCE OPERATES ON THE CHEYENNE
DIVIDE THIS MORNING. GIVEN THE 8 PM 5 INCH SNOWFALL REPORT FROM
THE COOP OBSERVER AT BIG SPRINGS...WINTER STORM CONDITIONS ARE
LIKELY UNDERWAY IN DEUEL COUNTY. SO A WINTER STORM WARNING HAS
BEEN ISSUED FOR THAT COUNTY.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 353 AM CST SUN FEB 23 2014
ROAD SURFACES IN MANY AREAS CROSSED THE FREEZING MARK OVERNIGHT
AND THE SNOW MELTED AN REFROZE PRODUCING HAZARDOUS TRAVEL SO THE
WINTER WEATHER ADVISORY CONTINUES THIS MORNING.
AS ADVERTISED BY THE HIGH RESOLUTION MODELS...THE NAM...ARF...NMM
AND SREF...A COUPLED JET DEVELOPED ACROSS THE FORECAST AREA. THE
HEAVY SNOW WAS LOCALIZED ACROSS CHASE AND HAYES COUNTIES AND
PERHAPS A FEW OTHER AREAS. THE MODELS IN GENERAL SHOWED FAIR
SKILL FORECASTING THIS BUT NEAR ZERO SKILL IN LOCATION. 50 MILES
OF FORECAST ERROR WITH THE LOCATION. THE NAM BOUNCED AROUND
FAVORING CNTL LINCOLN COUNTY...THEN SRN LINCOLN COUNTY AND THEN
KEITH COUNTY. MODEL SKILL IN PREDICTING THE LOCATION OF MESOSCALE
HEAVY SNOW BANDS WAS POOR. THE WINTER STORM WARNING FOR CHASE AND
HAYES COUNTIES CONTINUES THIS MORNING. THE RADAR OUT OF KGLD
CONTINUES TO SHOW LIGHT TO MODERATE SNOW AS THIS FORMERLY HEAVY
BAND OF SNOW IS WEAKENING.
THE LATEST RADAR OUT OF KCYS IN CONJUNCTION WITH THE RAP AND NAM
MODELS SUGGESTS A SECOND BAND OF LIGHT TO MODERATE SNOW WILL MOVE
INTO WRN NEBRASKA THIS MORNING AND THEN LIFT SLOWLY NORTH AS A
DEVELOPING WARM FRONT THIS AFTERNOON AND TONIGHT. BARRING THE
DEVELOPMENT OF AN ORGANIZED HEAVY SNOW BAND...IT IS BELIEVED
SNOWFALL AMOUNTS TODAY WILL BE AN INCH OR LESS USING A 13 TO 1
RATIO WHICH HAS BEEN THE PREVAILING MARKER OUTSIDE OF THE HEAVY
SNOW BAND WHICH DEVELOPED ACROSS FAR SOUTHERN NEBRASKA LAST NIGHT.
THUS FAR...KLBF MEASURED 0.19 INCHES OF LIQUID WITH ABOUT 2
INCHES OF SNOWFALL. AN ADDITIONAL 0.08 IS FORECAST TODAY FOR A
TOTAL OF 0.27 INCHES. YESTERDAYS MODEL MEDIAN QPF WHICH WAS USED
FOR THE FORECAST WAS 0.28. THUS THE ACCURACY OF THE SNOWFALL
FORECAST HINGES ON THE SNOW TO WATER RATIO WHICH IS HIGHLY
DEPENDENT ON DEEP LIFT TO PRODUCE HIGH RATIOS.
THE COBB METHODOLOGY CONTINUES TO ADVERTISE VERY HIGH RATIOS OF
17 TO 20 TO 1 TODAY AND TONIGHT. THESE RATIOS ARE SUSPECT AND
LIKELY BIASED TOWARD THE DEVELOPMENT OF DEEP VERTICAL LIFT SO 13
TO 1 WAS USED TODAY. THE HIGH COBB RATIOS WERE USED
TONIGHT...NEAR 20 TO 1 AT KVTN...BUT HPC HAS OUTLOOKED THIS AREA
FOR SLIGHT RISK OF 4 INCHES OF ACCUMULATION. THE MEDIAN QPF AT
KVTN IS ABOUT 0.15 INCHES AND THE FORECAST IS FOR 0.15. THE 20 TO
1 RATIO THEN PRODUCES 3 INCHES OF SNOW FOR VALENTINE.
THE NAM SUGGESTS GENERALLY MODERATE LIFT AND MID LEVEL
FRONTOGENESIS TONIGHT ACROSS THE NORTH...NO WHERE NEAR THE
STRENGTH EXHIBITED BY THE COUPLED JET STRUCTURE SATURDAY NIGHT
ACROSS THE SOUTH BUT THERE IS POTENTIAL FOR A PERIOD OF MODERATE
SNOW AS THERE IS BANDING POTENTIAL. GIVEN THE UNCERTAINTIES OF
FCSTING BANDED SNOW...A MIDDLE OF THE ROAD FORECAST IS IN PLACE
FOR THE NORTH TONIGHT.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 353 AM CST SUN FEB 23 2014
MONDAY MORNING WILL CONTINUE TO SEE SNOW ACROSS THE NORTHERN PART
OF THE CWA AS THE NEXT WAVE CONTINUES TO PUSH ACROSS S DAKOTA AND
NORTHEAST NEB. MODELS ARE IN FAIR AGREEMENT WITH THE BAND OF SNOW
TO LINGER THROUGH MONDAY MORNING THEN DIMINISHES FOR THE
AFTERNOON. HIGHEST AMOUNTS OF ADDITIONAL SNOW LIKELY AROUND AN
INCH IN THE MORNING BEFORE BECOMING LIGHT AND PUSHING EAST.
HOWEVER YET ANOTHER DISTURBANCE IS FORECAST TO TRACK ACROSS THE
HIGH PLAINS FOR LATE MONDAY INTO TUESDAY. COLD ARCTIC HIGH
PRESSURE WILL BEGIN TO PUSH ACROSS SOUTHERN CANADA BY MONDAY
EVENING. THIS WILL BRING IN SOME DRIER AIR ACROSS THE NORTHERN
PLAINS WITH THE MAIN SNOW BANDING EXPECTED ACROSS THE SOUTHWESTERN
PART OF THE CWA. DEPTH OF THE DENDRITIC GROWTH ZONE IS FAIRLY
DEEP...HOWEVER THE BEST OMEGA IS ACROSS THE HIGHER TERRAIN TO THE
WEST. WILL HAVE TO OVER COME A SOMEWHAT DRY LOWER LEVEL WITH TOP
DOWN SATURATION...ALTHOUGH SHOULD RESULT IN AROUND AN INCH OR TWO
OF SNOW. IF A BAND OF SNOW BECOMES MORE STATIONARY...WHICH IS NOT
SUGGESTED AT THIS TIME BY THE MODELS...BUT AFTER SEE LAST NIGHTS
BAND CAN NOT BE RULED OUT...ANOTHER ADVISORY FOR 2 TO 4 INCHES
WOULD BE WARRANTED.
THE COLD HIGH PRESSURE WILL BEGIN TO BE NOTICES WITH TEMPS
FALLING TO NEAR ZERO FOR TUESDAY MORNING. TUESDAY AFTERNOON AS
THE SNOW DIMINISHES FROM THE NORTH...CLOUDS WILL BE ON THE
DECREASE. COLD ARCTIC AIR WILL SPREAD ACROSS THE AREA WITH HIGHS
STRUGGLING INTO THE 20S. BY TUESDAY NIGHT THE DISTURBANCE WILL BE
SE AND CLEARING SKIES ASSOCIATED WITH THE SFC HIGH WILL COMBINE
WITH THE SNOW PACK TO PRODUCE A VERY COLD LATE FEBRUARY NIGHT.
WIDESPREAD SINGLE DIGITS...AND MOST NOT TO FAR FROM ZERO. LOCALLY
BELOW ZERO STILL POSSIBLE...HOWEVER CENTER OF THE HIGH IS OVER
HEAD CLOSER TO MIDNIGHT SO TEMPS MIGHT BEGIN TO CLIMB OR AT LEAST
HOLD STEADY FOR THE EARLY MORNING HOURS.
SW WINDS DEVELOP FOR WED...ON THE BACK SIDE OF THE HIGH...WITH
WARMER AIR TO PUSH ACROSS THE AREA. HIGHS WARM INTO THE
30S...HOWEVER SNOW PACK COULD PLAY A ROLL IN TEMPS BELOW GUIDANCE.
REST OF THE WORK WEEK WILL CONTINUES TO SEE A RIDGE ACROSS THE
SOUTHERN ROCKIES WHICH TRAILS TO THE NW INTO THE PAC NORTHWEST.
THIS FAVORS A NORTHWEST FLOW AND PROGRESSIVE CLIPPER SYSTEM AND ON
AND OFF CLOUDS AND MAYBE SOME LIGHT SNOW. BY THE WEEKEND BOTH THE
GFS AND THE EC ARE CARVING A TROUGH ACROSS THE WESTERN CONUS WITH
MORE ZONAL FLOW EAST OF THE ROCKIES. WILL CONTINUE TO MONITOR THIS
SYSTEM WHICH MODELS EJECT ONTO THE PLAINS LATE SATURDAY INTO
SUNDAY. STILL A WEEK OUT BUT SOMETHING TO MONITOR.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 513 AM CST SUN FEB 23 2014
VFR IS EXPECTED ALONG AND EAST OF HIGHWAY 183 TODAY. MIXED VFR/IFR
IN SNOW AND CIGS IS EXPECTED WEST OF HWY 183.
THE ONGOING SNOW ACROSS WRN NEBRASKA IS EXPECTED TO CONTINUE THIS
MORNING AND LIFT SLOWLY NORTH INTO NRN NEB THIS AFTERNOON. TONIGHT
IT IS EXPECTED TO MOVE EAST THROUGH NRN NEB. IFR SHOULD BE FAIRLY
WIDESPREAD IN THIS AREA OF SNOW WITH CONDITIONS WORSENING
WESTWARD.
MVFR CIGS ARE EXPECTED ELSEWHERE TONIGHT BUT THIS COULD TURN OUT
TO BE VFR AT OVC035-040 AS THE MODEL CONSENSUS COULD BE
FORECASTING CIG HEIGHTS TOO LOW.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL NOON CST /11 AM MST/ TODAY FOR
NEZ022>025-035>038-058-059-071.
WINTER STORM WARNING UNTIL NOON CST /11 AM MST/ TODAY FOR NEZ056-
057-069-070.
&&
$$
UPDATE...CDC
SHORT TERM...CDC
LONG TERM...MASEK
AVIATION...CDC
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
546 AM CST SUN FEB 23 2014
.UPDATE...
ISSUED AT 538 AM CST SUN FEB 23 2014
THE METAR AT KOGA IS SHOWING 1 MILE VSBY WITH MODERATE SNOW. THE
NEDOR CAMS IN DEUEL COUNTY SHOW SIGNIFICANT ON THE GROUND AND
STILL FALLING AS THE SECOND DISTURBANCE OPERATES ON THE CHEYENNE
DIVIDE THIS MORNING. GIVEN THE 8 PM 5 INCH SNOWFALL REPORT FROM
THE COOP OBSERVER AT BIG SPRINGS...WINTER STORM CONDITIONS ARE
LIKELY UNDERWAY IN DEUEL COUNTY. SO A WINTER STORM WARNING HAS
BEEN ISSUED FOR THAT COUNTY.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 353 AM CST SUN FEB 23 2014
ROAD SURFACES IN MANY AREAS CROSSED THE FREEZING MARK OVERNIGHT
AND THE SNOW MELTED AN REFROZE PRODUCING HAZARDOUS TRAVEL SO THE
WINTER WEATHER ADVISORY CONTINUES THIS MORNING.
AS ADVERTISED BY THE HIGH RESOLUTION MODELS...THE NAM...ARF...NMM
AND SREF...A COUPLED JET DEVELOPED ACROSS THE FORECAST AREA. THE
HEAVY SNOW WAS LOCALIZED ACROSS CHASE AND HAYES COUNTIES AND
PERHAPS A FEW OTHER AREAS. THE MODELS IN GENERAL SHOWED FAIR
SKILL FORECASTING THIS BUT NEAR ZERO SKILL IN LOCATION. 50 MILES
OF FORECAST ERROR WITH THE LOCATION. THE NAM BOUNCED AROUND
FAVORING CNTL LINCOLN COUNTY...THEN SRN LINCOLN COUNTY AND THEN
KEITH COUNTY. MODEL SKILL IN PREDICTING THE LOCATION OF MESOSCALE
HEAVY SNOW BANDS WAS POOR. THE WINTER STORM WARNING FOR CHASE AND
HAYES COUNTIES CONTINUES THIS MORNING. THE RADAR OUT OF KGLD
CONTINUES TO SHOW LIGHT TO MODERATE SNOW AS THIS FORMERLY HEAVY
BAND OF SNOW IS WEAKENING.
THE LATEST RADAR OUT OF KCYS IN CONJUNCTION WITH THE RAP AND NAM
MODELS SUGGESTS A SECOND BAND OF LIGHT TO MODERATE SNOW WILL MOVE
INTO WRN NEBRASKA THIS MORNING AND THEN LIFT SLOWLY NORTH AS A
DEVELOPING WARM FRONT THIS AFTERNOON AND TONIGHT. BARRING THE
DEVELOPMENT OF AN ORGANIZED HEAVY SNOW BAND...IT IS BELIEVED
SNOWFALL AMOUNTS TODAY WILL BE AN INCH OR LESS USING A 13 TO 1
RATIO WHICH HAS BEEN THE PREVAILING MARKER OUTSIDE OF THE HEAVY
SNOW BAND WHICH DEVELOPED ACROSS FAR SOUTHERN NEBRASKA LAST NIGHT.
THUS FAR...KLBF MEASURED 0.19 INCHES OF LIQUID WITH ABOUT 2
INCHES OF SNOWFALL. AN ADDITIONAL 0.08 IS FORECAST TODAY FOR A
TOTAL OF 0.27 INCHES. YESTERDAYS MODEL MEDIAN QPF WHICH WAS USED
FOR THE FORECAST WAS 0.28. THUS THE ACCURACY OF THE SNOWFALL
FORECAST HINGES ON THE SNOW TO WATER RATIO WHICH IS HIGHLY
DEPENDENT ON DEEP LIFT TO PRODUCE HIGH RATIOS.
THE COBB METHODOLOGY CONTINUES TO ADVERTISE VERY HIGH RATIOS OF
17 TO 20 TO 1 TODAY AND TONIGHT. THESE RATIOS ARE SUSPECT AND
LIKELY BIASED TOWARD THE DEVELOPMENT OF DEEP VERTICAL LIFT SO 13
TO 1 WAS USED TODAY. THE HIGH COBB RATIOS WERE USED
TONIGHT...NEAR 20 TO 1 AT KVTN...BUT HPC HAS OUTLOOKED THIS AREA
FOR SLIGHT RISK OF 4 INCHES OF ACCUMULATION. THE MEDIAN QPF AT
KVTN IS ABOUT 0.15 INCHES AND THE FORECAST IS FOR 0.15. THE 20 TO
1 RATIO THEN PRODUCES 3 INCHES OF SNOW FOR VALENTINE.
THE NAM SUGGESTS GENERALLY MODERATE LIFT AND MID LEVEL
FRONTOGENESIS TONIGHT ACROSS THE NORTH...NO WHERE NEAR THE
STRENGTH EXHIBITED BY THE COUPLED JET STRUCTURE SATURDAY NIGHT
ACROSS THE SOUTH BUT THERE IS POTENTIAL FOR A PERIOD OF MODERATE
SNOW AS THERE IS BANDING POTENTIAL. GIVEN THE UNCERTAINTIES OF
FCSTING BANDED SNOW...A MIDDLE OF THE ROAD FORECAST IS IN PLACE
FOR THE NORTH TONIGHT.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 353 AM CST SUN FEB 23 2014
MONDAY MORNING WILL CONTINUE TO SEE SNOW ACROSS THE NORTHERN PART
OF THE CWA AS THE NEXT WAVE CONTINUES TO PUSH ACROSS S DAKOTA AND
NORTHEAST NEB. MODELS ARE IN FAIR AGREEMENT WITH THE BAND OF SNOW
TO LINGER THROUGH MONDAY MORNING THEN DIMINISHES FOR THE
AFTERNOON. HIGHEST AMOUNTS OF ADDITIONAL SNOW LIKELY AROUND AN
INCH IN THE MORNING BEFORE BECOMING LIGHT AND PUSHING EAST.
HOWEVER YET ANOTHER DISTURBANCE IS FORECAST TO TRACK ACROSS THE
HIGH PLAINS FOR LATE MONDAY INTO TUESDAY. COLD ARCTIC HIGH
PRESSURE WILL BEGIN TO PUSH ACROSS SOUTHERN CANADA BY MONDAY
EVENING. THIS WILL BRING IN SOME DRIER AIR ACROSS THE NORTHERN
PLAINS WITH THE MAIN SNOW BANDING EXPECTED ACROSS THE SOUTHWESTERN
PART OF THE CWA. DEPTH OF THE DENDRITIC GROWTH ZONE IS FAIRLY
DEEP...HOWEVER THE BEST OMEGA IS ACROSS THE HIGHER TERRAIN TO THE
WEST. WILL HAVE TO OVER COME A SOMEWHAT DRY LOWER LEVEL WITH TOP
DOWN SATURATION...ALTHOUGH SHOULD RESULT IN AROUND AN INCH OR TWO
OF SNOW. IF A BAND OF SNOW BECOMES MORE STATIONARY...WHICH IS NOT
SUGGESTED AT THIS TIME BY THE MODELS...BUT AFTER SEE LAST NIGHTS
BAND CAN NOT BE RULED OUT...ANOTHER ADVISORY FOR 2 TO 4 INCHES
WOULD BE WARRANTED.
THE COLD HIGH PRESSURE WILL BEGIN TO BE NOTICES WITH TEMPS
FALLING TO NEAR ZERO FOR TUESDAY MORNING. TUESDAY AFTERNOON AS
THE SNOW DIMINISHES FROM THE NORTH...CLOUDS WILL BE ON THE
DECREASE. COLD ARCTIC AIR WILL SPREAD ACROSS THE AREA WITH HIGHS
STRUGGLING INTO THE 20S. BY TUESDAY NIGHT THE DISTURBANCE WILL BE
SE AND CLEARING SKIES ASSOCIATED WITH THE SFC HIGH WILL COMBINE
WITH THE SNOW PACK TO PRODUCE A VERY COLD LATE FEBRUARY NIGHT.
WIDESPREAD SINGLE DIGITS...AND MOST NOT TO FAR FROM ZERO. LOCALLY
BELOW ZERO STILL POSSIBLE...HOWEVER CENTER OF THE HIGH IS OVER
HEAD CLOSER TO MIDNIGHT SO TEMPS MIGHT BEGIN TO CLIMB OR AT LEAST
HOLD STEADY FOR THE EARLY MORNING HOURS.
SW WINDS DEVELOP FOR WED...ON THE BACK SIDE OF THE HIGH...WITH
WARMER AIR TO PUSH ACROSS THE AREA. HIGHS WARM INTO THE
30S...HOWEVER SNOW PACK COULD PLAY A ROLL IN TEMPS BELOW GUIDANCE.
REST OF THE WORK WEEK WILL CONTINUES TO SEE A RIDGE ACROSS THE
SOUTHERN ROCKIES WHICH TRAILS TO THE NW INTO THE PAC NORTHWEST.
THIS FAVORS A NORTHWEST FLOW AND PROGRESSIVE CLIPPER SYSTEM AND ON
AND OFF CLOUDS AND MAYBE SOME LIGHT SNOW. BY THE WEEKEND BOTH THE
GFS AND THE EC ARE CARVING A TROUGH ACROSS THE WESTERN CONUS WITH
MORE ZONAL FLOW EAST OF THE ROCKIES. WILL CONTINUE TO MONITOR THIS
SYSTEM WHICH MODELS EJECT ONTO THE PLAINS LATE SATURDAY INTO
SUNDAY. STILL A WEEK OUT BUT SOMETHING TO MONITOR.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 513 AM CST SUN FEB 23 2014
VFR IS EXPECTED ALONG AND EAST OF HIGHWAY 183 TODAY. MIXED VFR/IFR
IN SNOW AND CIGS IS EXPECTED WEST OF HWY 183.
THE ONGOING SNOW ACROSS WRN NEBRASKA IS EXPECTED TO CONTINUE THIS
MORNING AND LIFT SLOWLY NORTH INTO NRN NEB THIS AFTERNOON. TONIGHT
IT IS EXPECTED TO MOVE EAST THROUGH NRN NEB. IFR SHOULD BE FAIRLY
WIDESPREAD IN THIS AREA OF SNOW WITH CONDITIONS WORSENING
WESTWARD.
MVFR CIGS ARE EXPECTED ELSEWHERE TONIGHT BUT THIS COULD TURN OUT
TO BE VFR AT OVC035-040 AS THE MODEL CONSENSUS COULD BE
FORECASTING CIG HEIGHTS TOO LOW.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL NOON CST /11 AM MST/ TODAY FOR
NEZ022>025-035>038-057>059-071.
WINTER STORM WARNING UNTIL NOON CST /11 AM MST/ TODAY FOR NEZ056-
069-070.
&&
$$
UPDATE...CDC
SHORT TERM...CDC
LONG TERM...MASEK
AVIATION...CDC
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
514 AM CST SUN FEB 23 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 353 AM CST SUN FEB 23 2014
ROAD SURFACES IN MANY AREAS CROSSED THE FREEZING MARK OVERNIGHT
AND THE SNOW MELTED AN REFROZE PRODUCING HAZARDOUS TRAVEL SO THE
WINTER WEATHER ADVISORY CONTINUES THIS MORNING.
AS ADVERTISED BY THE HIGH RESOLUTION MODELS...THE NAM...ARF...NMM
AND SREF...A COUPLED JET DEVELOPED ACROSS THE FORECAST AREA. THE
HEAVY SNOW WAS LOCALIZED ACROSS CHASE AND HAYES COUNTIES AND
PERHAPS A FEW OTHER AREAS. THE MODELS IN GENERAL SHOWED FAIR
SKILL FORECASTING THIS BUT NEAR ZERO SKILL IN LOCATION. 50 MILES
OF FORECAST ERROR WITH THE LOCATION. THE NAM BOUNCED AROUND
FAVORING CNTL LINCOLN COUNTY...THEN SRN LINCOLN COUNTY AND THEN
KEITH COUNTY. MODEL SKILL IN PREDICTING THE LOCATION OF MESOSCALE
HEAVY SNOW BANDS WAS POOR. THE WINTER STORM WARNING FOR CHASE AND
HAYES COUNTIES CONTINUES THIS MORNING. THE RADAR OUT OF KGLD
CONTINUES TO SHOW LIGHT TO MODERATE SNOW AS THIS FORMERLY HEAVY
BAND OF SNOW IS WEAKENING.
THE LATEST RADAR OUT OF KCYS IN CONJUNCTION WITH THE RAP AND NAM
MODELS SUGGESTS A SECOND BAND OF LIGHT TO MODERATE SNOW WILL MOVE
INTO WRN NEBRASKA THIS MORNING AND THEN LIFT SLOWLY NORTH AS A
DEVELOPING WARM FRONT THIS AFTERNOON AND TONIGHT. BARRING THE
DEVELOPMENT OF AN ORGANIZED HEAVY SNOW BAND...IT IS BELIEVED
SNOWFALL AMOUNTS TODAY WILL BE AN INCH OR LESS USING A 13 TO 1
RATIO WHICH HAS BEEN THE PREVAILING MARKER OUTSIDE OF THE HEAVY
SNOW BAND WHICH DEVELOPED ACROSS FAR SOUTHERN NEBRASKA LAST NIGHT.
THUS FAR...KLBF MEASURED 0.19 INCHES OF LIQUID WITH ABOUT 2
INCHES OF SNOWFALL. AN ADDITIONAL 0.08 IS FORECAST TODAY FOR A
TOTAL OF 0.27 INCHES. YESTERDAYS MODEL MEDIAN QPF WHICH WAS USED
FOR THE FORECAST WAS 0.28. THUS THE ACCURACY OF THE SNOWFALL
FORECAST HINGES ON THE SNOW TO WATER RATIO WHICH IS HIGHLY
DEPENDENT ON DEEP LIFT TO PRODUCE HIGH RATIOS.
THE COBB METHODOLOGY CONTINUES TO ADVERTISE VERY HIGH RATIOS OF
17 TO 20 TO 1 TODAY AND TONIGHT. THESE RATIOS ARE SUSPECT AND
LIKELY BIASED TOWARD THE DEVELOPMENT OF DEEP VERTICAL LIFT SO 13
TO 1 WAS USED TODAY. THE HIGH COBB RATIOS WERE USED
TONIGHT...NEAR 20 TO 1 AT KVTN...BUT HPC HAS OUTLOOKED THIS AREA
FOR SLIGHT RISK OF 4 INCHES OF ACCUMULATION. THE MEDIAN QPF AT
KVTN IS ABOUT 0.15 INCHES AND THE FORECAST IS FOR 0.15. THE 20 TO
1 RATIO THEN PRODUCES 3 INCHES OF SNOW FOR VALENTINE.
THE NAM SUGGESTS GENERALLY MODERATE LIFT AND MID LEVEL
FRONTOGENESIS TONIGHT ACROSS THE NORTH...NO WHERE NEAR THE
STRENGTH EXHIBITED BY THE COUPLED JET STRUCTURE SATURDAY NIGHT
ACROSS THE SOUTH BUT THERE IS POTENTIAL FOR A PERIOD OF MODERATE
SNOW AS THERE IS BANDING POTENTIAL. GIVEN THE UNCERTAINTIES OF
FCSTING BANDED SNOW...A MIDDLE OF THE ROAD FORECAST IS IN PLACE
FOR THE NORTH TONIGHT.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 353 AM CST SUN FEB 23 2014
MONDAY MORNING WILL CONTINUE TO SEE SNOW ACROSS THE NORTHERN PART
OF THE CWA AS THE NEXT WAVE CONTINUES TO PUSH ACROSS S DAKOTA AND
NORTHEAST NEB. MODELS ARE IN FAIR AGREEMENT WITH THE BAND OF SNOW
TO LINGER THROUGH MONDAY MORNING THEN DIMINISHES FOR THE
AFTERNOON. HIGHEST AMOUNTS OF ADDITIONAL SNOW LIKELY AROUND AN
INCH IN THE MORNING BEFORE BECOMING LIGHT AND PUSHING EAST.
HOWEVER YET ANOTHER DISTURBANCE IS FORECAST TO TRACK ACROSS THE
HIGH PLAINS FOR LATE MONDAY INTO TUESDAY. COLD ARCTIC HIGH
PRESSURE WILL BEGIN TO PUSH ACROSS SOUTHERN CANADA BY MONDAY
EVENING. THIS WILL BRING IN SOME DRIER AIR ACROSS THE NORTHERN
PLAINS WITH THE MAIN SNOW BANDING EXPECTED ACROSS THE SOUTHWESTERN
PART OF THE CWA. DEPTH OF THE DENDRITIC GROWTH ZONE IS FAIRLY
DEEP...HOWEVER THE BEST OMEGA IS ACROSS THE HIGHER TERRAIN TO THE
WEST. WILL HAVE TO OVER COME A SOMEWHAT DRY LOWER LEVEL WITH TOP
DOWN SATURATION...ALTHOUGH SHOULD RESULT IN AROUND AN INCH OR TWO
OF SNOW. IF A BAND OF SNOW BECOMES MORE STATIONARY...WHICH IS NOT
SUGGESTED AT THIS TIME BY THE MODELS...BUT AFTER SEE LAST NIGHTS
BAND CAN NOT BE RULED OUT...ANOTHER ADVISORY FOR 2 TO 4 INCHES
WOULD BE WARRANTED.
THE COLD HIGH PRESSURE WILL BEGIN TO BE NOTICES WITH TEMPS
FALLING TO NEAR ZERO FOR TUESDAY MORNING. TUESDAY AFTERNOON AS
THE SNOW DIMINISHES FROM THE NORTH...CLOUDS WILL BE ON THE
DECREASE. COLD ARCTIC AIR WILL SPREAD ACROSS THE AREA WITH HIGHS
STRUGGLING INTO THE 20S. BY TUESDAY NIGHT THE DISTURBANCE WILL BE
SE AND CLEARING SKIES ASSOCIATED WITH THE SFC HIGH WILL COMBINE
WITH THE SNOW PACK TO PRODUCE A VERY COLD LATE FEBRUARY NIGHT.
WIDESPREAD SINGLE DIGITS...AND MOST NOT TO FAR FROM ZERO. LOCALLY
BELOW ZERO STILL POSSIBLE...HOWEVER CENTER OF THE HIGH IS OVER
HEAD CLOSER TO MIDNIGHT SO TEMPS MIGHT BEGIN TO CLIMB OR AT LEAST
HOLD STEADY FOR THE EARLY MORNING HOURS.
SW WINDS DEVELOP FOR WED...ON THE BACK SIDE OF THE HIGH...WITH
WARMER AIR TO PUSH ACROSS THE AREA. HIGHS WARM INTO THE
30S...HOWEVER SNOW PACK COULD PLAY A ROLL IN TEMPS BELOW GUIDANCE.
REST OF THE WORK WEEK WILL CONTINUES TO SEE A RIDGE ACROSS THE
SOUTHERN ROCKIES WHICH TRAILS TO THE NW INTO THE PAC NORTHWEST.
THIS FAVORS A NORTHWEST FLOW AND PROGRESSIVE CLIPPER SYSTEM AND ON
AND OFF CLOUDS AND MAYBE SOME LIGHT SNOW. BY THE WEEKEND BOTH THE
GFS AND THE EC ARE CARVING A TROUGH ACROSS THE WESTERN CONUS WITH
MORE ZONAL FLOW EAST OF THE ROCKIES. WILL CONTINUE TO MONITOR THIS
SYSTEM WHICH MODELS EJECT ONTO THE PLAINS LATE SATURDAY INTO
SUNDAY. STILL A WEEK OUT BUT SOMETHING TO MONITOR.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 513 AM CST SUN FEB 23 2014
VFR IS EXPECTED ALONG AND EAST OF HIGHWAY 183 TODAY. MIXED VFR/IFR
IN SNOW AND CIGS IS EXPECTED WEST OF HWY 183.
THE ONGOING SNOW ACROSS WRN NEBRASKA IS EXPECTED TO CONTINUE THIS
MORNING AND LIFT SLOWLY NORTH INTO NRN NEB THIS AFTERNOON. TONIGHT
IT IS EXPECTED TO MOVE EAST THROUGH NRN NEB. IFR SHOULD BE FAIRLY
WIDESPREAD IN THIS AREA OF SNOW WITH CONDITIONS WORSENING
WESTWARD.
MVFR CIGS ARE EXPECTED ELSEWHERE TONIGHT BUT THIS COULD TURN OUT
TO BE VFR AT OVC035-040 AS THE MODEL CONSENSUS COULD BE
FORECASTING CIG HEIGHTS TOO LOW.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL NOON CST /11 AM MST/ TODAY FOR
NEZ022>025-035>038-056>059-071.
WINTER STORM WARNING UNTIL NOON CST /11 AM MST/ TODAY FOR NEZ069-
070.
&&
$$
SHORT TERM...CDC
LONG TERM...MASEK
AVIATION...CDC
FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
530 AM CST SUN FEB 23 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 301 AM CST SUN FEB 23 2014
CURRENTLY AS OF 09Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED RIDGING FROM THE EASTERN PACIFIC INTO ALASKA...A BROAD UPPER
LOW OVER THE CANADIAN ARCHIPELAGO...AND BROAD TROUGHING ACROSS ALL
OF SOUTHERN CANADA INTO THE UPPER MIDWEST. SHORTWAVES OF NOTE FOR
THIS FORECAST INCLUDE ONE OVER WEST CENTRAL BRITISH COLUMBIA...ONE
OVER CENTRAL ALBERTA...AND THE LAST AS PART OF THE UPPER LOW ON THE
WESTERN SIDE OF THE CANADIAN ARCHIPELAGO. A NORTHWEST 925MB FLOW
CONTINUES TO GRADUALLY DRAW COLDER IN OUT OF CANADA TOWARDS THE
FORECAST AREA...NOTED BY THE 00Z MPX SOUNDING AT -15C. THAT SAME
SOUNDING ALSO CONTINUES TO DEPICT PLENTY OF DRY AIR...RESULTING IN
CLEAR SKIES EARLY THIS MORNING. COMBINATION OF THE CLEAR SKIES AND
COOLING 925MB TEMPS HAS ALLOWED TEMPERATURES TO DROP INTO THE SINGLE
DIGITS ABOVE ZERO. IF THE 5 TO 15 MPH BREEZE WAS NOT PRESENT TO KEEP
THE AIR MIXED...TEMPERATURES WOULD PROBABLY BE A LOT COLDER.
OVERALL LITTLE CHANGE IS PROGGED BY MODELS TO OCCUR IN THE NEXT 24
HOURS IN TERMS OF THE UPPER LEVEL PATTERN OVER THE UPPER MIDWEST AND
THE FORECAST AREA. WE STILL REMAIN UNDER THE INFLUENCE OF A DRY
NORTHWEST LOW TO MID LEVEL FLOW...WHICH SHOULD HELP KEEP SKIES
MAINLY CLEAR THROUGH TODAY AND MUCH OF TONIGHT. THERE ARE SOME
INDICATIONS OF CIRRUS APPROACHING LOCATIONS WEST OF THE MISSISSIPPI
RIVER LATE TONIGHT...BUT THATS REALLY ABOUT IT FOR CLOUDS.
925MB TEMPS TODAY ARE FORECAST TO RANGE BETWEEN -13 AND -16C...ABOUT
1-2C COLDER THAN YESTERDAY. THEREFORE...WE SHOULD SEE HIGHS JUST
SLIGHTLY COOLER THAN YESTERDAY. SKIES STAYING CLEAR THROUGH
MUCH OF TONIGHT PLUS 925MB TEMPS FALLING TO -14 TO -19C...COLDEST
OVER WISCONSIN...SHOULD ALLOW FOR LOWS IN MOST LOCATIONS IN THE
SINGLE DIGITS BELOW ZERO. AGAIN...THERE LOOKS TO BE A PERSISTENT
NORTHWEST BREEZE THROUGH TONIGHT HELPING TO PREVENT DECOUPLING.
STILL...THE TYPICAL COLD SPOTS COULD TRY TO APPROACH -10F. WIND
CHILLS LOOK TO GET CLOSE TO ADVISORY CRITERIA...BUT TOO MARGINAL AT
THIS POINT TO ISSUE AN ADVISORY.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 301 AM CST SUN FEB 23 2014
THE 2 MAIN IMPACTS REMAIN FOR THE LONG TERM...
1. POTENTIAL FOR SOME SNOW LATE MONDAY AFTERNOON AND NIGHT
2. THE BITTER COLD AIR...ESPECIALLY TUESDAY NIGHT AND BEYOND.
REGARDING IMPACT NUMBER 1...THE SHORTWAVES CURRENTLY OVER CENTRAL
BRITISH COLUMBIA AND ALBERTA REMAIN PROGGED TO PHASE TOGETHER OVER
THE DAKOTAS ON MONDAY...THEN QUICKLY SLIDE THROUGH THE FORECAST AREA
AROUND 06Z TUESDAY. MOISTURE IS LACKING FOR THESE SHORTWAVES...WITH
PRECIPITABLE WATER CLIMBING TO 0.1-0.2 OF AN INCH. HOWEVER...SOME
WEAK ISENTROPIC LIFT ON THE 275-280K SURFACES COMBINED WITH DPVA
AHEAD OF THE SHORTWAVES SHOULD BE ENOUGH TO SQUEEZE OUT SOME LIGHT
SNOW. SNOW SHOULD BE SOMEWHAT FLUFFY...THOUGH THE BULK OF THE LIFT
LOOKS TO OCCUR ABOVE THE DENDRITIC GROWTH ZONE. TIMING WISE...MODELS
CONTINUE TO SLOW DOWN THE SNOW MOVING INTO THE AREA...WITH THE
23.00Z NAM/GFS/CANADIAN/ECMWF KEEPING MUCH OF THE SNOW WEST OF THE
AREA PRIOR TO 00Z TUESDAY. ITS MORE OF A MONDAY NIGHT SNOW NOW. DID
RAISE CHANCES UP FOR MONDAY EVENING WEST OF THE MISSISSIPPI RIVER
WITH GOOD MODEL AGREEMENT FOR THE SNOW THEN. AFTER 06Z MONDAY...
MODELS DIVERGE ON HOW MUCH SNOW MIGHT BE LEFT WITH THE 23.00Z
GFS/CANADIAN DRY WHEREAS THE NAM AND ECMWF STILL HAVE SOME SNOW
LEFT. SPLIT THE DIFFERENCE AND HAVE SOME 20-30 PERCENT CHANCES FOR
NOW. IT APPEARS MUCH OF THIS HAS TO DO WITH THE TIMING OF THE PHASED
SHORTWAVE.
NOW IMPACT NUMBER 2...THE COLD. IN THE WAKE OF MONDAY NIGHTS
SHORTWAVE TROUGH...925MB TEMPS FALL TO -15 TO -20C. A SECOND AND
MORE POTENT COLD SURGE REMAINS PROGGED TO PLUNGE INTO THE AREA
TUESDAY NIGHT...DROPPING 925MB TEMPS TO -23 TO -25C BY 12Z
WEDNESDAY. THIS SURGE IS BEHIND THAT SHORTWAVE CURRENTLY OVER THE
CANADIAN ARCHIPELAGO. WIND CHILL ADVISORIES SEEM ALL BUT LIKELY
TUESDAY NIGHT INTO WEDNESDAY MORNING. A BRIEF BOUT OF WARM ADVECTION
IS SUGGESTED FOR WEDNESDAY AHEAD OF AN ARCTIC COLD FRONT
DROPPING SOUTH OUT OF CANADA...THOUGH IT APPEARS A BRISK WEST WIND
WILL ACCOMPANY IT. THEN ITS BACK TO THE COLD AS ANOTHER IMPRESSIVE
SURGE OF ARCTIC AIR DIVES SOUTH INTO THE REGION FOR THURSDAY ON
SOME BRISK NORTHWEST WINDS. 925MB TEMPS FROM THE 23.00Z GFS AND
ECMWF DROP TO -23 TO -27C BY 12Z THURSDAY...WHILE 850MB TEMPS
APPROACH -30C ACROSS OUR NORTH. THESE READINGS ARE NEARLY 3 STANDARD
DEVIATIONS BELOW NORMAL. BEYOND THURSDAY...MODELS BEGIN TO DIVERGE
A BIT WITH THE HANDLING OF THE COLD AIR. THE 23.00Z GFS TRIES TO
MODIFY THE COLD AIR SOMEWHAT FROM THE FLOW BECOMING MORE ZONAL
ACROSS THE NORTHERN TIER OF THE U.S.. THE 23.00Z ECMWF ALONG WITH
EXTRAPOLATION OF THE CANADIAN HAS THAT SAME ZONAL FLOW...JUST A
SMIDGE FURTHER SOUTH...WHICH RESULTS IN A CONTINUATION OF THE DEEP
FREEZE. FOR THE FORECAST LEANED A BIT CLOSER TOWARDS THE ECMWF.
OVERALL FOR TEMPERATURES TUESDAY THROUGH SATURDAY...STAYED CLOSE TO
A CONSENSUS OF 30 DAY BIAS CORRECTED GUIDANCE...WHICH PERFORMED WELL
IN PAST COLD SPELLS THIS WINTER. THURSDAY NIGHT COULD BE VERY COLD
WITH A SURFACE RIDGE PARKED OVERHEAD. WOULD NOT BE SURPRISED IF
SOME OF THE TYPICAL COLD SPOTS TO APPROACH -30F.
GIVEN HOW DEEP SOME OF THE FROST IS ALREADY...WATER MAINS UNDER
ROADS WILL NEED TO BE WATCHED CLOSELY. LUCKILY THE HIGHER SUN ANGLE
CAN HEAT THE TOP OF THE ROAD SURFACES MORE NOW THAN IN JANUARY...BUT
STILL THIS COLD AIR WILL NOT BE GOOD. THERE ARE STRONG INDICATIONS
TOO FROM THE CFS THAT THE BELOW NORMAL WEATHER COULD PERSIST THROUGH
ALL OF MARCH.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY)
ISSUED AT 530 AM CST SUN FEB 23 2014
DRY/COLD CANADIAN HIGH PRESSURE...WITH RIDGING INTO IA...WILL REMAIN
CENTERED OVER ALB/SASKAT TODAY/TONIGHT...WITH GOOD VFR CONDITIONS
EXPECTED THRU THE PERIOD INTO MONDAY. A MODEST PRESSURE GRADIENT
WILL REMAIN OVER THE AREA...FOR WEST TO NORTHWEST WINDS MOSTLY IN
THE 10 TO 15 KT RANGE THRU TONIGHT. STEEP LOW LEVEL LAPSE RATES AND
SOME DEEPER MIXING TO NEAR 925MB THIS AFTERNOON LOOKS TO RESULT IN
SOME GUSTINESS OF THE WINDS THIS AFTERNOON...MAINLY AT THE HIGHER
ELEVATION/OPEN COUNTRY SITES LIKE KRST. CONTINUED THE MENTION OF
WIND GUSTS AT KRST IN THE 19Z-24Z TIMEFRAME.
&&
.CLIMATE...
ISSUED AT 301 AM CST SUN FEB 23 2014
GIVEN ALL THE COLD AIR TO ROUND OUT THE MONTH OF FEBRUARY...HERE IS
HOW FEBRUARY AND THE WINTER WOULD STACK UP BASED ON THE CURRENT
FORECAST...
...FOR THE MONTH OF FEBRUARY...
LA CROSSE... 9.5 AVERAGE TEMPERATURE...4TH COLDEST
COLDER FEBRUARYS...
1873... 3.9
1936... 4.3
1899... 9.4
ROCHESTER... 6.9 AVERAGE TEMPERATURE...4TH COLDEST
COLDER FEBRUARYS...
1936... 0.5
1979... 5.7
1917... 6.0
...FOR THE WINTER...DECEMBER THROUGH FEBRUARY...
LA CROSSE... 11.6 AVERAGE TEMPERATURE...5TH COLDEST
COLDER WINTERS...
1872-1873... 8.4
1874-1875... 10.5
1977-1978... 11.4
1935-1936... 11.4
ROCHESTER... 8.9 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
AREA FORECAST DISCUSSION
NWS PUEBLO CO
323 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 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 300 PM MST SUN FEB 23 2014
VFR CONDITIONS THROUGH THE NEXT 24 HOURS AT ALL THREE TERMINALS.
WESTERLY WINDS ARE FORECAST TO DEVELOP AT KPUB WITH GUSTS TO 30 KTS
POSSIBLE MONDAY AFTERNOON. MOZLEY
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
FIRE WEATHER WATCH FROM MONDAY MORNING THROUGH MONDAY AFTERNOON
FOR COZ228>230.
&&
$$
SHORT TERM...MOZLEY
LONG TERM...HODANISH
AVIATION...MOZLEY
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1033 AM MST SUN FEB 23 2014
.UPDATE...
&&
.SHORT TERM...LOW CLOUDS AND AREAS OF FOG RELUCTANT TO DISSIPATE OVER
THE SOUTH PLATTE BASIN...INCLUDING NORTHERN AND CENTRAL PORTIONS
OF THE I-25 CORRIDOR. ALTHOUGH VSBYS ARE BEGINNING TO IMPROVE SUCH
AS THE CHANGE AT DIA FROM 1/4 MILE TO 2 MILES IN THE PAST FEW
MINS.SLOWEST TO CLEAR OUT WILL BE AREAS ACROSS THE NORTHEAST
CORNER WHERE NEW BLANKET OF SNOW WILL CONTINUE TO CHILL THE BNDRY
LAYER AND WITH THE HIGHER CLOUD DECK GENERATED BY THE NEARBY JET
WILL CONTINUE TO BLOCK OUT SUNSHINE. MEANWHILE...DRAMATIC
CLEARING WAS UNDERWAY OVER AND NEAR THE HIGHER TERRAIN TO THE
SOUTH AND SOUTHEAST OF DENVER WITH DRIER AIR MIXING DOWN OFF THE
FOOTHILLS AND ALOFT. AT PRESENT RATE SHOULD SEE CLEARING SPREADING
NORTHWARD OVER THE REMAINDER OF THE DENVER METRO AREA OVER THE
NEXT COUPLE OF HOURS..AND THE FOG DISSIPATING IN MOST AREAS BY
NOON OR SHORTLY THEREAFTER. BECAUSE OF THE SLOW CLEARING...FELT IT
NECESSARY TO LOWER HIGH TEMPERATURES ON THE PLAINS BY AT LEAST A
FEW DEGS UP AGAINST THE FOOTHILLS...AND AS MUCH AS 5-10 DEG F
FARTHER OUT ON THE PLAINS IN THE CLOUDY AREAS. FURTHERMORE...HAVE
OBSERVED A MODEST JUMP IN WIND SPEEDS AT FRONT RANGE RECORDING
PAST COUPLE OF HOURS. RUC AND NAM ALSO SHOW THIS TREND. SO NUDGED
UP SPEEDS IN THIS AREA FOR THE REMAINDER OF THE DAY. COULD SEE
GUSTSAROUND 50 MPH IN PARTS OF THE FOOTHILLS... WITH POSSIBLE
GUSTS AROUND 65 MPH ON THE HIGHER PEAKS.
TONIGHT...MODELS SHOW A RETURN OF BOUNDARY LAYER MOISTURE UP THE
SOUTH PLATTE RIVER BASIN WITH EAST-SOUTHEAST LOW-LEVEL FLOW.
RH FIELDS INDICATE NEAR SATURATED AIR IN THE AREA OVERNIGHT. SO
INTRODUCED AREAS OF FOG AND LOW CLOUDS FOR AREAS ROUGHLY NORTH AND
EAST OF THE DENVER AREA FOR MOST OF TONIGHT. DOWNSLOPE FLOW OFF
THE FOOTHILLS SHOULD KEEP THE LOW CLOUDS AND FOG OUT OF THE
DENVER METRO AREA...EXCEPT PERHAPS ITS FAR NORTHERN SUBURBS AND
COMMUNITIES.
.AVIATION...ILS-IFR CONDITIONS DUE TO LOW CIGS AND FOG AT DENVER
AREA AIRPORTS EXPECTED THROUGH 1830Z...THEN GRADUAL IMPROVEMENT
FROM THE SOUTH AND WEST AS DRIER AIR MOVES DOWN OF THE FOOTHILLS
AND PALMER DIVIDE. COULD SEE VFR CONDITIONS AT BJC AND APA BY 19Z
OR 20Z. WHEREAS...DIA MAY CONTINUE TO SEE IFR CONDITIONS THROUGH
19Z...THEN A GRADUAL LIFT IN CIGS AND VSBYS THEREAFTER WITH LIGHT
SFC WINDS GRADUALLY BECOMING EAST-SOUTHEAST IN DIRECTION. SHOULD
SEE CLEARING OVERNIGHT...HOWEVER...PATCHY LOW CLOUDS AND FOG MAY
FORM AGAIN IN THE DIA AREA AFTER 04Z TONIGHT...WITH VSBYS
POSSIBLY AS LOW AS 3 MILES IN PATCHY FOG.
&&
.PREV DISCUSSION... /ISSUED 417 AM MST SUN FEB 23 2014/
SHORT TERM...SNOW IS LIFTING TO THE ENE ABOUT AS EXPECTED WITH
DRIER AIR ALOFT MOVING IN. STILL DECENT SNOW RIGHT ALONG THE
NORTHERN BORDER AND OVER THE NORTHERN MOUNTAINS FOR A FEW MORE
HOURS. ADVISORIES ARE SET TO EXPIRE AT 6 AM AND THAT LOOKS ABOUT
RIGHT. MEANWHILE THERE IS A SOLID STRATUS DECK ON THE PLAINS AND
WITH SOUTHEAST WINDS DEVELOPING EXPECT THAT THIS WILL HANG ON
LONGER THAN WE HAD PREVIOUSLY FORECAST. COULD BE A RAGGED EDGE TO
THIS CLOUD DECK OVER THE DENVER AREA COMPLICATING THE FORECAST. WE
HAVE HAD SOME PLACES WHERE IT HAS CLEARED AND THE STRATUS FILLED
IN AT A LOWER HEIGHT...AND STILL A FEW PATCHES OF LOWER CLOUDS
BENEATH IT...NOTABLY FROM GREELEY INTO DIA. NOT SO SURE OF THE
DENSE FOG AT THE AIRPORT...BUT IN GENERAL EXPECTING PERSISTENCE
FOR MUCH OF THE MORNING WITH A SLOW BURN OFF THE REST OF THE DAY.
WE ARE ALREADY SHOWING QUITE A TEMPERATURE GRADIENT FROM DENVER
TOWARD THE NORTHEAST CORNER OF THE STATE...WHICH WILL BE ENHANCED
BY BOTH THE TIMING OF THE CLEARING AND THE NEW SNOW COVER. IF THE
CLEARING IS MUCH SLOWER WE COULD BE TOO WARM IN DENVER.
FOR TONIGHT...THERE COULD BE SOME STRATUS LINGERING/REDEVELOPING
OR ADVECTING INTO THE EASTERN BORDER AREA AS SOUTHERLY WINDS
CONTINUE. OTHERWISE RELATIVELY CLEAR SKIES SHOULD ALLOW
TEMPERATURES TO DROP FAIRLY WELL DESPITE SOME WIND AND THE WARMING
ALOFT. DROPPED FORECAST LOWS JUST SLIGHTLY. ALSO ADDED SOME MORE
WIND TO THE MOUNTAINS AS THE FLOW ALOFT INCREASES AGAIN AND WE MAY
START TO GET A MOUNTAINTOP INVERSION FOR A BETTER EAST SLOPE WAVE
LATE TONIGHT.
LONG TERM...IT IS ALL WEST-NORTHWESTERLY FLOW ALOFT FOR THE
FORECAST AREA MONDAY THROUGH TUESDAY NIGHT. THE JET MAXIMUM
GENERALLY STAYS JUST NORTHEAST OF COLORADO THROUGH THE PERIOD.
THE SYNOPTIC SCALE ENERGY IS QUITE WEAK ALL FOUR PERIODS. THE
BOUNDARY LAYER FLOW IS DOWNSLOPING SOUTHWESTERLY MONDAY INTO THE
AFTERNOON. A COLD FRONT COMES IN MONDAY AFTERNOON...WITH UPSLOPE
BEHIND IT FOR THE PLAINS AND FOOTHILLS THROUGH MUCH OF MONDAY
NIGHT. ANOTHER COLD FRONT MOVES IN TUESDAY MORNING WITH PRETTY
DECENT UPSLOPE TUESDAY AFTERNOON INTO THE EARLY EVENING. NORMAL
DRAINAGE WIND PATTERNS SEEM REASONABLE LATER TUESDAY NIGHT. FOR
MOISTURE...THERE ISN`T A LOT AROUND ON MONDAY EARLY...BUT IT
STARTS TO INCREASE IN THE AFTERNOON. IT GETS DEEPER OVER THE
MOUNTAINS MONDAY NIGHT...AND THERE IS SOME IN THE LOWER LEVELS
OVER THE PLAINS. MOISTURE INCREASES ON TUESDAY AND IT IS PRETTY
DEEP OVER ALL THE CWA TUESDAY AFTERNOON THROUGH TUESDAY MIDNIGHT
..THEN IT DECREASES. THE QPF FIELDS HAVE A TAD OF MEASURABLE
SNOWFALL OVER THE NORTHERN CWA MONDAY LATE DAY INTO THE EVENING.
BETTER MEASURABLE SNOW COVERING MUCH OF THE CWA IS PROGGED ON
TUESDAY FROM 18Z INTO 06Z TUESDAY EVENING. MODELS ARE ALL OVER THE
PLACE WHEN COMPARED TO ONE ANOTHER. FOR POPS...WILL UP THEM ON
TUESDAY FOR MOST OF THE CWA. THERE WILL BE NONE FOR MONDAY...AND A
TAD MONDAY NIGHT. FOR TEMPERATURES...WILL BE A BIT WARMER THAN
TODAY. TUESDAY LOOKS TO BE CONSIDERABLY COLDER. THE NAM MOS HAS A
HIGH OF 55 F FOR DIA TUESDAY...THE ECMWF MOS HAS 24 F. FOR THE
LATER DAYS...WEDNESDAY THROUGH SATURDAY...MODELS SHOW WEAKENING
NORTHWESTERLY FLOW ALOFT WEDNESDAY...WITH A DYING UPPER RIDGE
MOVING IN WEDNESDAY NIGHT. THERE IS A WEAK UPPER TROUGH FOR LATE
THURSDAY. STRONGER WEST-NORTHWESTERLY FLOW ALOFT IS IN PLACE
FRIDAY...THEN SOUTHWESTERLY FLOW ALOFT ON SATURDAY WITH A
DEVELOPING TROUGH TO THE WEST. CONFIDENCE IS A BIT SHAKY.
AVIATION...EXPECT STRATUS TO LINGER IN THE DENVER AREA THROUGH
16Z-18Z...WITH SLOWER CLEARING ON THE EASTERN PLAINS. SUSPECT THE
DENSE FOG AT KDEN AT THIS TIME IS NOT WIDESPREAD...BUT WITH LIGHT
NE WINDS AND POSSIBLY CLOUDS ABOVE IT THERE COULD BE LIFR
CONDITIONS THERE AS LATE AS 16Z. VFR CONDITIONS SHOULD DEVELOP BY
18Z AND CONTINUE THROUGH TONIGHT.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BAKER
LONG TERM....RJK
AVIATION...BAKER
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
155 PM CST SUN FEB 23 2014
.DISCUSSION...
213 AM CST
TODAY...
BROAD SFC RIDGE STRETCHES FROM THE NORTHERN PLAINS SOUTHEAST
THROUGH THE WESTERN OHIO VALLEY. THIS HAS RESULTED IN A LIGHT
NORTHWEST FLOW ACROSS NORTHERN IL/NORTHWEST IN EARLY THIS MORNING.
BAROCLINIC ZONE REMAINS ORIENTED FROM CENTRAL MO STRETCHING
NORTHEAST THROUGH CENTRAL IL/IN AND DRIFTING SOUTHEAST. IR IMAGERY
SHOWS THE AREA OF CLOUDS WELL...ASSOCIATED WITH THIS BAND OF
PRECIP. THEN JUST WEST OF THIS FEATURE WAS YET ANOTHER WEAK MID-
LVL WAVE THAT HAD ANOTHER AREA OF MID/UPR LVL MOISTURE ASSOCIATED
WITH IT AND WAS SLIDING EAST...BEING STEERED BY THE SEMI-ZONAL
FLOW IN THE MID-LVLS.
TEMPS THIS MORNING WILL HOVER AROUND THE TEENS FOR THE BULK OF THE
FORECAST AREA...PERHAPS HOLDING IN UPR TEENS/LOW 20S FOR THE
SOUTHERN CWFA. OTHERWISE FOR TODAY HIGH PRESSURE WILL PUSH THIS AREA
OF CLOUDS THIS MORNING TO THE SOUTH...AND ALLOW FOR A DRY DAY. SKIES
WILL EVENTUALLY BECOME P-CLOUDY BY MIDDAY...WITH HIGHS WARMING
MAINLY INTO THE 20S. CLOSER TO 30 FOR THE FAR SOUTHERN CWFA.
THEN FOR TONIGHT...HIGH PRESSURE WILL CONTINUE TO HOLD ACROSS THE
FORECAST AREA AND LIMIT CLOUD COVER. JUST NORTH OF THE AREA
THOUGH...AND CLOSER TO A STRONGER MID-LVL VORT WILL BE THICKER CLOUD
COVER. WINDS WILL GENERALLY REMAIN LIGHT FROM THE NORTHWEST...WHICH
COUPLED WITH 850MB TEMPS HOVERING ARND -10 TO -12 DEG C SHOULD LIMIT
HOW COOL TEMPS RADIATE OVERNIGHT. SO HAVE ONLY NUDGED TEMPS DOWN A
LITTLE...GENERALLY IN THE SINGLE DIGITS ABOVE ZERO. COULD SEE SOME
OF THE TRADITIONALLY COOLER LOCATIONS DIP TO ARND ZERO BY DAYBREAK
MON.
CONFIDENCE...HIGH.
MONDAY THROUGH TUESDAY...
500MB TROUGH AXIS OVER THE GREAT LAKES REGION PUSHES EAST...WITH AN
AREA OF WEAK RIDGING ARRIVING MIDDAY MON OVER THE FORECAST AREA.
HOWEVER GIVEN THE SEMI-ZONAL FLOW...WHICH IS GENERALLY A MORE
PROGRESSIVE SETUP...THE NEXT WAVE CONTINUES TO BE PROGGED FOR
ARRIVAL MON LATE AFTN/EVE. LATEST FORECAST GUIDANCE HAS CONTINUED TO
SUGGEST THE MID-LVL HEIGHT RISES MAY BE A LITTLE SLOWER TO DEPART
THE REGION...WHICH WOULD LIKELY HAVE AN INFLUENCE ON THE WEAK WAVE
ARRIVING POSSIBLY LATER. THE MAIN TIMING DOES APPEAR TO BE
CONSISTENT WITH JUST AFT 00Z TUE...AND GIVEN THE PREV-DISCUSSED
PROGRESSIVE FLOW...SKIES WILL THICKEN RATHER QUICKLY AND CIGS WILL
LOWER WITH EASE. LOCAL MODEL INDICATES A SLIGHTLY LATER ARRIVAL AND
CLOSER TO 6Z TUE...BUT ALSO IS INDICATING THE WAVE WILL BE WEAKENING
UPON ARRIVAL. CONFIDENCE ON THIS WAVE WEAKENING AS IT ARRIVES IS
VERY LOW...GIVEN THE DECENT MID-LVL FORCING ASSOCIATED. TEMPS
CONTINUE TO BE COOL ENOUGH TO SUPPORT LGT SNOW FOR THE AREA...AND
EXPECT SLR ARND 15:1 TO 18:1. THIS WILL LIKELY PRODUCE A QUICK 1 TO
2 INCHES OF SNOWFALL ACROSS MOST OF THE CWFA. BY 12-15Z TUE...THE
BULK OF THE WAVE/SNOW WILL BE PUSHING EAST AND COMING TO AN END.
THEN FOR TUE...500MB TROUGH AXIS ARRIVES AS AN ARCTIC AIRMASS
CONTINUES TO PUSH SOUTH FROM CANADA TOWARDS THE UPPER MIDWEST TUE
AFTN. CURRENTLY EXPECT HIGHS TUE TO HOLD IN THE TEENS/LOW
20S...HOWEVER BY TUE NGT THE BOUNDARY WILL BE PUSHING ACROSS THE
FORECAST AREA AND TEMPS WILL BE DROPPING TO A FEW DEGREES BELOW
ZERO.
CONFIDENCE...HIGH.
CONFIDENCE IN SNOW ACCUMS MON EVE/OVERNIGHT...HIGH.
WEDNESDAY THROUGH SUNDAY...
ENSEMBLES AND OPERATIONAL SOLUTIONS HAVE CONTINUED TO BE IN GOOD
AGREEMENT WITH THE ARRIVAL OF YET ANOTHER ARCTIC AIRMASS. BY WED THE
500MB TROUGH AXIS WILL BE OVERHEAD. CURRENT PROGS INDICATE TEMPS IN
MID-LVLS WILL HOVER ARND -20 TO -25 DEG C. WHEN APPLYING THIS
TOWARDS LOCAL CLIMATE WHICH LIKELY YIELD HIGH TEMPS WED IN THE
SINGLE DIGITS ABOVE ZERO TO POSSIBLY THE LOW TEENS. SFC RIDGE WILL
BE SLIDING OVER THE AREA AS WELL...WHICH SHOULD LIMIT HOW MUCH LOWER
WIND CHILL VALUES WILL BE WED. THEN FOR WED NGT...FLOW GRADUALLY
TURNS WESTERLY IN THE LLVLS. A WEAK SHORTWAVE IS PROGGED TO CLIP THE
NORTHERN GREAT LAKES REGION...HOWEVER EXPECT GENERALLY DRY WEATHER
FOR THE FORECAST AREA WED/WED NGT.
FOR THE REMAINDER OF THE EXTENDED PERIODS...ENSEMBLES REMAIN IN
DECENT AGREEMENT WITH YET ANOTHER SFC RIDGE SLIDING SOUTHEAST FROM
CENTRAL CANADA TOWARDS THE PLAINS AND STRETCHING EAST TO THE WESTERN
GREAT LAKES THUR. THIS SHOULD HELP TO MAINTAIN UNSEASONABLY COLD
CONDS FOR THE FORECAST AREA...WITH TEMPS STRUGGLING TO WARM BEYOND
THE LOW/MID TEENS THUR AFTN.
STRONG VORTEX BEGINS TO LIFT NORTHEAST THUR NGT/FRI...WITH SOME
MODERATION TO TEMPS POISED FOR THE END OF THE WEEK INTO THE FIRST
HALF OF NEXT WEEKEND. ALTHOUGH THIS IS RELATIVE...AS TEMPS WILL
CONTINUE TO BE UNSEASONABLY COOL IN THE TEENS/LOW 20S. GUIDANCE IS
SUGGESTING THE SOUTHERN STREAM WILL BECOME ACTIVE YET AGAIN IN THE
LATER PERIODS...AND INDICATES THE PRECIP WILL REMAIN SOUTH OF THE
CWFA. ALTHOUGH COULD SEE SOME ADJUSTMENTS TO THE PLACEMENT OF EACH
SOUTHERN STREAM WAVE.
CONFIDENCE...MEDIUM/HIGH.
BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* NONE.
JEE
//DISCUSSION...UPDATED 18Z...
A LARGE SURFACE RIDGE STRETCHES THROUGH THE TERMINALS THIS AFTN
AND IT WILL REMAIN STATIONARY THROUGH THE PERIOD. VFR CONDITIONS
ARE EXPECTED WITH GUSTY W TO NW WINDS THIS AFTN...ARND 18 KT.
GUSTS SUBSIDE THIS EVENING WITH W TO NW WINDS 10-12KT CONTINUING.
GUSTS REDEVELOP BY MID MONDAY MORNING BUT ONLY TO 16 KT. THE
GRADIENT THEN SLACKENS RESULTING IN SUSTAINED 10 KT WEST WINDS
LATE IN THE AFTERNOON. CLOUD COVER WILL THICKEN AS WELL LATE
MONDAY AFTERNOON BUT REMAIN VFR.
LOOKING AHEAD...SNOW IS STILL EXPECTED MONDAY NIGHT INTO TUESDAY
WITH LIGHT ACCUMULATIONS POSSIBLE.
JEE
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* HIGH CONFIDENCE IN ALL FORECAST ELEMENTS.
JEE
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
MONDAY NIGHT...SNOW LIKELY WITH LIGHT ACCUMULATIONS POSSIBLE.
TUESDAY THROUGH SATURDAY...VFR LIKELY.
BMD
&&
.MARINE...
154 PM CST
LOW PRESSURE CENTERED NEAR JAMES BAY THIS AFTERNOON CONTINUES TO
WEAKEN THIS AFTERNOON. HOWEVER...A BROAD EXPANSIVE RIDGE OF SURFACE
HIGH PRESSURE...EXTENDING FROM THE NORTHERN PLAINS EAST
SOUTHEASTWARD ACROSS THE OHIO VALLEY...IS PRODUCING AN ENHANCED
PRESSURE GRADIENT ACROSS LAKE MICHIGAN. THIS WILL CONTINUE TO
SUPPORT WESTERLY WINDS UP TO 30 KT AT TIMES INTO TONIGHT. GIVEN THAT
SOME OF THESE STRONG WINDS WILL ALSO SET UP ACROSS THE SOUTHERN TIP
OF LAKE MICHIGAN TONIGHT...IT APPEARS WAVES IN THE ICE FREE AREAS OF
NORTHWESTERN INDIANA WILL GET WAVES OVER 4 FEET THROUGH MONDAY.
THEREFORE A SMALL CRAFT ADVISORY WILL BE ISSUED FOR LATE TONIGHT
THROUGH MONDAY EVENING...MAINLY FOR THE NEAR SHORE AREAS EAST OF
GARY INDIANA.
A COUPLE OF CLIPPER TYPE SYSTEMS ARE EXPECTED TO DROP
SOUTHEASTWARD ACROSS THE LAKES REGION THIS WEEK. THE FIRST...WILL
DROP ACROSS SOUTHEASTERN ONTARIO LATE TUESDAY INTO TUESDAY NIGHT.
THIS LOOKS TO RESULT IN AN ENHANCEMENT TO THE WIND FIELD AS A COLD
FRONT DROPS ACROSS THE LAKE LATE TUESDAY AND TURNS TO WINDS OUT OF
THE NORTHWEST UP TO AROUND 30 KT FOR A PERIOD TUESDAY NIGHT INTO
EARLY WEDNESDAY. ANOTHER FAST MOVING CLIPPER SYSTEM IS EXPECTED TO
QUICKLY MOVE IN ACROSS THE GREAT LAKES REGION BY LATE WEDNESDAY.
THIS WILL RESULT IN BACKING WINDS OUT OF THE WEST-SOUTHWEST DURING
THE DAY WEDNESDAY AS SURFACE HIGH PRESSURE SETS UP ACROSS SOUTH
CENTRAL CONUS. WIND SPEEDS DURING THIS PERIOD APPEAR THAT THEY WILL
REACH GALE FORCE IN THE 35 TO 40 KT RANGE. THE WINDS WILL THAN SHIFT
BACK OUT OF THE NORTHWEST WEDNESDAY NIGHT AS ANOTHER STRONG COLD
FRONT PUSHES ACROSS THE LAKE. THESE NORTHWESTERLY WINDS COULD REMAIN
NEAR GALE FORCE FOR A SHORT PERIOD INTO EARLY THURSDAY...BUT AS HIGH
PRESSURE SETS UP OVER THE LAKE ON THURSDAY...WINDS WILL ABATE
SIGNIFICANTLY LATER IN THE DAY.
KJB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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Area Forecast Discussion
National Weather Service Lincoln IL
1128 AM CST Sun Feb 23 2014
.DISCUSSION...
ISSUED 956 AM CST Sun Feb 23 2014
Lingering band of light snow in the southeast CWA has pushed into
Indiana. Radar mosaics still showing quite a few returns along the
I-70 corridor, but these are mostly elevated as surface obs are
showing cloud heights of 7000 feet or higher, so little more than
flurries anticipated the remainder of the morning. Persistent mid
level clouds continue to stream over the remainder of the forecast
area and should continue through the afternoon. Lowered
temperatures a couple degrees across the southeast CWA as they
had continued to slip downward as the snow began a few hours ago,
but the forecast over the remainder of the area still is in decent
shape.
Geelhart
&&
.AVIATION...
ISSUED 1125 AM CST Sun Feb 23 2014
VFR conditions expected through the period, with ceilings
generally above 10,000 feet. Most likely period for skies to be
clear will be 06-12Z. After that, mid-level clouds will rapidly
increase from the northwest Monday morning ahead of the next
clipper system, although any associated precipitation is not
expected until early evening. Northwest winds to persist through
the period, due to high pressure over the Dakotas.
Geelhart
&&
.PREV DISCUSSION...
ISSUED 330 AM CST Sun Feb 23 2014
SHORT TERM...Today through Wednesday night
Surface cold front has pressed south of the Ohio River into NW AR
while 1042 mb arctic high pressure over Alberta was nosing into
the central and northern plains. Colder air easing south into
central IL early this morning with temps slipping through the 20s
over central IL and low to mid 30s in southeast IL. Temps as cold
as 19F at Galesburg and Lacon. Frontogenetic forecasting close to
850 mb boundary near I-70 had band of light snow that diminished
east into central IN past few hours with dusting to as much as 1
inch between I-72 and I-70. Will carry just slight chance of light
snow this morning over southeast IL per HRRR model run. Radar
mosaic shows light pcpn returns and mainly virga over northern MO
into NW counties. RUC & HRRR keeps most of this very light snow
west of central IL this morning but could be a few flurries this
morning into central IL. Clouds to decrease from the north during
the afternoon and linger longest in southeast IL. Much colder
highs today range from mid 20s from Peoria and Bloomington north
to 35-40F over southeast IL with Lawrenceville near 40F.
Arctic high pressure noses into the mid MS river valley tonight
and brings fair skies and cold lows of 5-10F from Lincoln north
and mid to upper teens in southeast IL. Clouds increase Monday
morning ahead of northern stream clipper system which digs into
the Midwest Monday night. Slowed down chances of light snow Monday
afternoon as central IL appear dry through sunset Monday with best
chances of light snow arriving Monday night northern half of CWA.
Generally less than 1 inch of snow with northern IL having as much
as 1-2 inches of snow possible. Highs Monday again in mid 20s
north and mid to upper 30s in southeast IL. Lows Monday night in
the teens central IL and lower 20s southeast IL. Chances of light
snow NE of central IL by Tuesday morning. Highs Tue range from
lower 20s northern areas to mid 30s in southeast IL.
Core of arctic high pressure settles into MO by 18Z/noon Wed and
brings even colder air into the region during middle of the week.
Lows overnight Tue night into early Wed morning could reach zero
to 5 below NW of IL river with single digit lows over much of
central IL and far southeast IL around 10F. Highs Wed in the mid
teens NE to lower 20s SW and SE areas. Lows Wed night again in the
single digits over northern half of CWA and lower teens south.
LONG TERM...Thursday through Saturday night
Temps modify slightly during end of week but still average below
normal through next weekend. The 8-14 day outlook for Mar 2-8 has
60-70% chance of below normal temperatures and 40% chance of above
normal precipitation, which has been the normal for this winter.
Generally dry and cold conditions expected late this week into
next weekend. Though ECMWF and GEM models show some light QPF
Friday while heavier QPF passes south of IL Friday. GFS model is
dry over IL on Friday. Stayed close to ALLblend pops late this
week and into the weekend which is dry.
07
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1120 AM CST SUN FEB 23 2014
.DISCUSSION...
213 AM CST
TODAY...
BROAD SFC RIDGE STRETCHES FROM THE NORTHERN PLAINS SOUTHEAST
THROUGH THE WESTERN OHIO VALLEY. THIS HAS RESULTED IN A LIGHT
NORTHWEST FLOW ACROSS NORTHERN IL/NORTHWEST IN EARLY THIS MORNING.
BAROCLINIC ZONE REMAINS ORIENTED FROM CENTRAL MO STRETCHING
NORTHEAST THROUGH CENTRAL IL/IN AND DRIFTING SOUTHEAST. IR IMAGERY
SHOWS THE AREA OF CLOUDS WELL...ASSOCIATED WITH THIS BAND OF
PRECIP. THEN JUST WEST OF THIS FEATURE WAS YET ANOTHER WEAK MID-
LVL WAVE THAT HAD ANOTHER AREA OF MID/UPR LVL MOISTURE ASSOCIATED
WITH IT AND WAS SLIDING EAST...BEING STEERED BY THE SEMI-ZONAL
FLOW IN THE MID-LVLS.
TEMPS THIS MORNING WILL HOVER AROUND THE TEENS FOR THE BULK OF THE
FORECAST AREA...PERHAPS HOLDING IN UPR TEENS/LOW 20S FOR THE
SOUTHERN CWFA. OTHERWISE FOR TODAY HIGH PRESSURE WILL PUSH THIS AREA
OF CLOUDS THIS MORNING TO THE SOUTH...AND ALLOW FOR A DRY DAY. SKIES
WILL EVENTUALLY BECOME P-CLOUDY BY MIDDAY...WITH HIGHS WARMING
MAINLY INTO THE 20S. CLOSER TO 30 FOR THE FAR SOUTHERN CWFA.
THEN FOR TONIGHT...HIGH PRESSURE WILL CONTINUE TO HOLD ACROSS THE
FORECAST AREA AND LIMIT CLOUD COVER. JUST NORTH OF THE AREA
THOUGH...AND CLOSER TO A STRONGER MID-LVL VORT WILL BE THICKER CLOUD
COVER. WINDS WILL GENERALLY REMAIN LIGHT FROM THE NORTHWEST...WHICH
COUPLED WITH 850MB TEMPS HOVERING ARND -10 TO -12 DEG C SHOULD LIMIT
HOW COOL TEMPS RADIATE OVERNIGHT. SO HAVE ONLY NUDGED TEMPS DOWN A
LITTLE...GENERALLY IN THE SINGLE DIGITS ABOVE ZERO. COULD SEE SOME
OF THE TRADITIONALLY COOLER LOCATIONS DIP TO ARND ZERO BY DAYBREAK
MON.
CONFIDENCE...HIGH.
MONDAY THROUGH TUESDAY...
500MB TROUGH AXIS OVER THE GREAT LAKES REGION PUSHES EAST...WITH AN
AREA OF WEAK RIDGING ARRIVING MIDDAY MON OVER THE FORECAST AREA.
HOWEVER GIVEN THE SEMI-ZONAL FLOW...WHICH IS GENERALLY A MORE
PROGRESSIVE SETUP...THE NEXT WAVE CONTINUES TO BE PROGGED FOR
ARRIVAL MON LATE AFTN/EVE. LATEST FORECAST GUIDANCE HAS CONTINUED TO
SUGGEST THE MID-LVL HEIGHT RISES MAY BE A LITTLE SLOWER TO DEPART
THE REGION...WHICH WOULD LIKELY HAVE AN INFLUENCE ON THE WEAK WAVE
ARRIVING POSSIBLY LATER. THE MAIN TIMING DOES APPEAR TO BE
CONSISTENT WITH JUST AFT 00Z TUE...AND GIVEN THE PREV-DISCUSSED
PROGRESSIVE FLOW...SKIES WILL THICKEN RATHER QUICKLY AND CIGS WILL
LOWER WITH EASE. LOCAL MODEL INDICATES A SLIGHTLY LATER ARRIVAL AND
CLOSER TO 6Z TUE...BUT ALSO IS INDICATING THE WAVE WILL BE WEAKENING
UPON ARRIVAL. CONFIDENCE ON THIS WAVE WEAKENING AS IT ARRIVES IS
VERY LOW...GIVEN THE DECENT MID-LVL FORCING ASSOCIATED. TEMPS
CONTINUE TO BE COOL ENOUGH TO SUPPORT LGT SNOW FOR THE AREA...AND
EXPECT SLR ARND 15:1 TO 18:1. THIS WILL LIKELY PRODUCE A QUICK 1 TO
2 INCHES OF SNOWFALL ACROSS MOST OF THE CWFA. BY 12-15Z TUE...THE
BULK OF THE WAVE/SNOW WILL BE PUSHING EAST AND COMING TO AN END.
THEN FOR TUE...500MB TROUGH AXIS ARRIVES AS AN ARCTIC AIRMASS
CONTINUES TO PUSH SOUTH FROM CANADA TOWARDS THE UPPER MIDWEST TUE
AFTN. CURRENTLY EXPECT HIGHS TUE TO HOLD IN THE TEENS/LOW
20S...HOWEVER BY TUE NGT THE BOUNDARY WILL BE PUSHING ACROSS THE
FORECAST AREA AND TEMPS WILL BE DROPPING TO A FEW DEGREES BELOW
ZERO.
CONFIDENCE...HIGH.
CONFIDENCE IN SNOW ACCUMS MON EVE/OVERNIGHT...HIGH.
WEDNESDAY THROUGH SUNDAY...
ENSEMBLES AND OPERATIONAL SOLUTIONS HAVE CONTINUED TO BE IN GOOD
AGREEMENT WITH THE ARRIVAL OF YET ANOTHER ARCTIC AIRMASS. BY WED THE
500MB TROUGH AXIS WILL BE OVERHEAD. CURRENT PROGS INDICATE TEMPS IN
MID-LVLS WILL HOVER ARND -20 TO -25 DEG C. WHEN APPLYING THIS
TOWARDS LOCAL CLIMATE WHICH LIKELY YIELD HIGH TEMPS WED IN THE
SINGLE DIGITS ABOVE ZERO TO POSSIBLY THE LOW TEENS. SFC RIDGE WILL
BE SLIDING OVER THE AREA AS WELL...WHICH SHOULD LIMIT HOW MUCH LOWER
WIND CHILL VALUES WILL BE WED. THEN FOR WED NGT...FLOW GRADUALLY
TURNS WESTERLY IN THE LLVLS. A WEAK SHORTWAVE IS PROGGED TO CLIP THE
NORTHERN GREAT LAKES REGION...HOWEVER EXPECT GENERALLY DRY WEATHER
FOR THE FORECAST AREA WED/WED NGT.
FOR THE REMAINDER OF THE EXTENDED PERIODS...ENSEMBLES REMAIN IN
DECENT AGREEMENT WITH YET ANOTHER SFC RIDGE SLIDING SOUTHEAST FROM
CENTRAL CANADA TOWARDS THE PLAINS AND STRETCHING EAST TO THE WESTERN
GREAT LAKES THUR. THIS SHOULD HELP TO MAINTAIN UNSEASONABLY COLD
CONDS FOR THE FORECAST AREA...WITH TEMPS STRUGGLING TO WARM BEYOND
THE LOW/MID TEENS THUR AFTN.
STRONG VORTEX BEGINS TO LIFT NORTHEAST THUR NGT/FRI...WITH SOME
MODERATION TO TEMPS POISED FOR THE END OF THE WEEK INTO THE FIRST
HALF OF NEXT WEEKEND. ALTHOUGH THIS IS RELATIVE...AS TEMPS WILL
CONTINUE TO BE UNSEASONABLY COOL IN THE TEENS/LOW 20S. GUIDANCE IS
SUGGESTING THE SOUTHERN STREAM WILL BECOME ACTIVE YET AGAIN IN THE
LATER PERIODS...AND INDICATES THE PRECIP WILL REMAIN SOUTH OF THE
CWFA. ALTHOUGH COULD SEE SOME ADJUSTMENTS TO THE PLACEMENT OF EACH
SOUTHERN STREAM WAVE.
CONFIDENCE...MEDIUM/HIGH.
BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* NONE.
JEE
//DISCUSSION...UPDATED 18Z...
A LARGE SURFACE RIDGE STRETCHES THROUGH THE TERMINALS THIS AFTN
AND IT WILL REMAIN STATIONARY THROUGH THE PERIOD. VFR CONDITIONS
ARE EXPECTED WITH GUSTY W TO NW WINDS THIS AFTN...ARND 18 KT.
GUSTS SUBSIDE THIS EVENING WITH W TO NW WINDS 10-12KT CONTINUING.
GUSTS REDEVELOP BY MID MONDAY MORNING BUT ONLY TO 16 KT. THE
GRADIENT THEN SLACKENS RESULTING IN SUSTAINED 10 KT WEST WINDS
LATE IN THE AFTERNOON. CLOUD COVER WILL THICKEN AS WELL LATE
MONDAY AFTERNOON BUT REMAIN VFR.
LOOKING AHEAD...SNOW IS STILL EXPECTED MONDAY NIGHT INTO TUESDAY
WITH LIGHT ACCUMULATIONS POSSIBLE.
JEE
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* HIGH CONFIDENCE IN ALL FORECAST ELEMENTS.
JEE
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
MONDAY NIGHT...SNOW LIKELY WITH LIGHT ACCUMULATIONS POSSIBLE.
TUESDAY THROUGH SATURDAY...VFR LIKELY.
BMD
&&
.MARINE...
302 AM CST
MODERATE WEST TO NORTHWEST WINDS ARE EXPECTED TO CONTINUE THROUGH
THE REMAINDER OF THE WEEKEND AND INTO THE MIDDLE OF NEXT WEEK ACROSS
LAKE MICHIGAN ON THE EASTERN PERIPHERY OF A STRONG RIDGE THAT
EXTENDS FROM THE CANADIAN ROCKIES INTO THE OHIO VALLEY. WINDS WILL
GENERALLY BE IN THE 20 TO 30 KT RANGE THROUGH TUESDAY...THEN A
SERIES OF LOWS WILL DROP FROM CANADA INTO THE GREAT LAKES
REGION...THE STRONGEST OF WHICH WILL BE WEDNESDAY NIGHT. A SURGE OF
ARCTIC AIR WILL OVERSPREAD THE WESTERN LAKES BEHIND THIS LOW AND A
PERIOD OF NORTHWESTERLY GALES IS POSSIBLE...ALONG WITH FREEZING
SPRAY. THE RIDGE WILL START TO BUILD CLOSER TO LAKE MICHIGAN LATER
IN THE WEEK AND INTO THE WEEKEND WITH WINDS DIMINISHING.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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Area Forecast Discussion
National Weather Service Lincoln IL
957 AM CST Sun Feb 23 2014
.DISCUSSION...
ISSUED 956 AM CST Sun Feb 23 2014
Lingering band of light snow in the southeast CWA has pushed into
Indiana. Radar mosaics still showing quite a few returns along the
I-70 corridor, but these are mostly elevated as surface obs are
showing cloud heights of 7000 feet or higher, so little more than
flurries anticipated the remainder of the morning. Persistent mid
level clouds continue to stream over the remainder of the forecast
area and should continue through the afternoon. Lowered
temperatures a couple degrees across the southeast CWA as they
had continued to slip downward as the snow began a few hours ago,
but the forecast over the remainder of the area still is in decent
shape.
Geelhart
&&
.AVIATION...
ISSUED 540 AM CST Sun Feb 23 2014
VFR conditions will prevail at all TAF sites next 24hrs. Mid
clouds around 9kft will overspread all sites this morning and
remain over the area/sites through the morning and into the
afternoon. Models indicate that the clouds will slide south away
from the TAF sites this afternoon, but satellite loop/trends show
clouds moving due east. So will keep at least BKN mid clouds over
the area into this evening. Then skies will clear around midnight.
Winds will be northerly to start and then shifts to northwesterly
as a high pressure ridge pushes into the area late this afternoon
and into the evening.
Auten
&&
.PREV DISCUSSION...
ISSUED 330 AM CST Sun Feb 23 2014
SHORT TERM...Today through Wednesday night
Surface cold front has pressed south of the Ohio River into NW AR
while 1042 mb arctic high pressure over Alberta was nosing into
the central and northern plains. Colder air easing south into
central IL early this morning with temps slipping through the 20s
over central IL and low to mid 30s in southeast IL. Temps as cold
as 19F at Galesburg and Lacon. Frontogenetic forecasting close to
850 mb boundary near I-70 had band of light snow that diminished
east into central IN past few hours with dusting to as much as 1
inch between I-72 and I-70. Will carry just slight chance of light
snow this morning over southeast IL per HRRR model run. Radar
mosaic shows light pcpn returns and mainly virga over northern MO
into NW counties. RUC & HRRR keeps most of this very light snow
west of central IL this morning but could be a few flurries this
morning into central IL. Clouds to decrease from the north during
the afternoon and linger longest in southeast IL. Much colder
highs today range from mid 20s from Peoria and Bloomington north
to 35-40F over southeast IL with Lawrenceville near 40F.
Arctic high pressure noses into the mid MS river valley tonight
and brings fair skies and cold lows of 5-10F from Lincoln north
and mid to upper teens in southeast IL. Clouds increase Monday
morning ahead of northern stream clipper system which digs into
the Midwest Monday night. Slowed down chances of light snow Monday
afternoon as central IL appear dry through sunset Monday with best
chances of light snow arriving Monday night northern half of CWA.
Generally less than 1 inch of snow with northern IL having as much
as 1-2 inches of snow possible. Highs Monday again in mid 20s
north and mid to upper 30s in southeast IL. Lows Monday night in
the teens central IL and lower 20s southeast IL. Chances of light
snow NE of central IL by Tuesday morning. Highs Tue range from
lower 20s northern areas to mid 30s in southeast IL.
Core of arctic high pressure settles into MO by 18Z/noon Wed and
brings even colder air into the region during middle of the week.
Lows overnight Tue night into early Wed morning could reach zero
to 5 below NW of IL river with single digit lows over much of
central IL and far southeast IL around 10F. Highs Wed in the mid
teens NE to lower 20s SW and SE areas. Lows Wed night again in the
single digits over northern half of CWA and lower teens south.
LONG TERM...Thursday through Saturday night
Temps modify slightly during end of week but still average below
normal through next weekend. The 8-14 day outlook for Mar 2-8 has
60-70% chance of below normal temperatures and 40% chance of above
normal precipitation, which has been the normal for this winter.
Generally dry and cold conditions expected late this week into
next weekend. Though ECMWF and GEM models show some light QPF
Friday while heavier QPF passes south of IL Friday. GFS model is
dry over IL on Friday. Stayed close to ALLblend pops late this
week and into the weekend which is dry.
07
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1114 AM CST SUN FEB 23 2014
.UPDATE...
ISSUED AT 516 AM CST SUN FEB 23 2014
RADAR TRENDS THE PAST SEVERAL HOURS SHOW A SLOW WEAKENING OF
RETURNS ACROSS NORTHERN MISSOURI. KSTJ AND KCNK HAVE BEEN THE ONLY
OBSERVATION SITES THAT HAVE REPORTED ANY SNOW. RAP MODEL TRENDS
CONTINUE TO SHOW A SUBSTANTIAL DRY LAYER BELOW 850MB IN THE
FORECAST SOUNDINGS.
A COUPLE OF FLURRIES CANNOT BE RULED OUT SOUTH OF A KTVK TO KMQB
LINE EARLY THIS MORNING. BASED ON RADAR TRENDS...A DRY FORECAST
STILL LOOKS REASONABLE.
&&
.SYNOPSIS...
ISSUED AT 300 AM CST SUN FEB 23 2014
06Z SFC ANALYSIS HAS A FRONTAL BOUNDARY FROM THE OHIO VALLEY INTO
THE SOUTHERN PLAINS. A WEAK TROF RAN THROUGH THE GREAT LAKES WHILE
HIGH PRESSURE WAS OVER THE NORTHERN PLAINS. DEW POINTS WERE IN THE
SINGLE DIGITS AND TEENS FROM THE NORTHERN PLAINS INTO THE UPPER
MIDWEST WITH 20S AND 30S FROM THE SOUTHERN GREAT LAKES AND OHIO
VALLEY INTO THE REMAINDER OF THE PLAINS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 300 AM CST SUN FEB 23 2014
THE NEXT WEAK DISTURBANCE ALOFT IS MOVING FROM THE PLAINS INTO THE
LOWER MISSOURI VALLEY. ALTHOUGH RADAR RETURNS LOOK IMPRESSIVE...NO
REPORTING STATION INDICATES PRECIPITATION REACHING THE GROUND.
FORECAST SOUNDINGS INDICATE A VERY DRY ATMOSPHERE WILL REMAIN IN
PLACE ACROSS THE AREA TODAY AND TONIGHT AS HIGH PRESSURE SLOWLY
BUILDS INTO THE MIDWEST.
AT THE VERY WORST A FEW FLURRIES MIGHT BE SEEN ACROSS THE EXTREME
SOUTHERN AREAS EARLY THIS MORNING. OTHERWISE DRY CONDITIONS WILL BE
SEEN ACROSS THE AREA TODAY AND TONIGHT. TEMPERATURES WILL AVERAGE
BELOW NORMAL.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 300 AM CST SUN FEB 23 2014
CONTINUED VERY COLD WITH NEAR RECORD LOW TEMPERATURES WITH LIGHT
SNOW LIKELY MANY AREAS ON MONDAY.
OVERVIEW...LITTLE SENSIBLE WEATHER ISSUES BESIDES LIGHT SNOW AND
FLURRIES WITH NEXT INFUSION OF ARCTIC AIR ARRIVING ON MONDAY. LOW
LEVEL THERMAL AND MOISTURE FIELDS SUGGESTS A 70/30 MIX OF HI-RES
ECMWF WITH GFS. DEEP NW CYCLONIC FLOW KEEPS ARCTIC AIR IN PLACE
DAYS 2 THROUGH 7 WITH LITTLE SENSIBLE WEATHER ISSUES. LOW LEVEL
THERMAL FIELDS SUPPORT NEAR RECORD TO RECORD LOW MINS WEDNESDAY AM
AND POSSIBLY AGAIN TOWARD FRIDAY DEPENDING ON HIGH PRESSURE TRACKS.
MONDAY...UPPED POPS TO LIKELY...MOSTLY MONDAY EVENING WITH CENTRAL
1/3 OR MORE OF FORECAST AREA TO RECEIVE 2 TO 3 HOURS OF LIGHT SNOW
AS WEAK DISTURBANCE PASSES. LOCAL TOOLS AND TECHNIQUES SUGGEST .5
TO LOCALLY NEAR 1 INCH OF A POWDERY DRY SNOW WITH LWE OF 20:1 OR MORE.
FAR NORTH AND SOUTH SECTIONS MAY RECEIVE MORE OF A DUSTING OF FLURRIES.
TEMPERATURES IN THE TEENS NORTH TO MID/UPPER 20S FAR SOUTH SECTIONS.
MONDAY NIGHT...LOWS AS A CHALLENGE AS CLEARING SHOULD OCCUR AFTER
MIDNIGHT NW TO NEAR DAYBREAK SE SECTIONS. HENCE...MINS NEAR ZERO ARE
SUGGESTED TO MID TEENS SE SECTIONS. LATER SHIFTS MAY NEED TO CHANGE
THESE VALUES BY 5+ DEGREES IF CLEARING IS EARLIER OR DELAYED.
TUESDAY...MUCH COLDER AIR TO RESULT IN NEARLY STEADY TEMPERATURES
WITH NW WINDS OF 10 TO 20 MPH TO KEEP WIND CHILLS IN SINGLE DIGITS
SE TO NEGATIVE SINGLE DIGITS NW SECTIONS DESPITE FAIR SKIES. TUESDAY
NIGHT...WINDS TO BECOME NEARLY CALM TOWARD DAYBREAK WITH STRONG AND
SHALLOW INVERSION. LOWS SHOULD BE NEAR OR BREAK RECORDS AS DESCRIBED
IN CLIMATE SECTION BELOW. THIS SUPPORTS -13 TO +4 SE WITH FAVORED
LOCATIONS MAY NEED TO TRIMMED EVEN FURTHER BY 2 TO 5 DEGREES IF
SEVERAL HOURS OF CALM TO NEARLY CALM WINDS AND CLEAR SKIES OCCUR.
THIS MAY RESULT IN WIND CHILLS WELL BELOW -20 DEGREES INTO LATE
MORNING.
WEDNESDAY THROUGH SATURDAY...CONTINUED QUITE COLD AND FAIR TO MOSTLY
FAIR AND GENERALLY DRY WITH LOWS WELL BELOW NORMAL BY 15 TO 20 DEGREES.
THIS SUPPORTS HIGHS MOSTLY IN THE TEENS WITH SOME UPPER SINGLE DIGITS
POSSIBLE NORTH AND LOWS SINGLE DIGITS AND POSSIBLY WELL INTO THE NEGATIVE
SINGLE DIGITS NORTH SECTIONS. NEXT WAVE OFF CALIFORNIA MAY REQUIRE
ADDING SNOW FRIDAY NIGHT AND ESPECIALLY SATURDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1109 AM CST SUN FEB 23 2014
A STALLED RIDGE OF HIGH PRESSURE WILL KEEP VFR CONDITIONS IN PLACE
THROUGH MONDAY MORNING. AN UPPER LEVEL DISTURBANCE WILL RACE OUT
OF THE NORTHERN ROCKIES AND THROUGH THE PLAINS TONIGHT AND MONDAY
SPREADING LIGHT SNOW OVER REGION MONDAY AFTERNOON AND EVENING
CAUSING A DETERIORATION IN FLIGHT CONDITIONS.
&&
.CLIMATE...
ISSUED AT 300 AM CST SUN FEB 23 2014
RECORD LOWS FOR FEBRUARY 26...
MOLINE.........-14 IN 1963
CEDAR RAPIDS...-08 IN 1950
DUBUQUE........-10 IN 1980
BURLINGTON.....-11 IN 1950
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...08
SYNOPSIS...08
SHORT TERM...08
LONG TERM...NICHOLS
AVIATION...DLF
CLIMATE...NICHOLS
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1225 PM MST SUN FEB 23 2014
.UPDATE...
ISSUED AT 1225 PM MST SUN FEB 23 2014
HAVE CANCELLED THE DENSE FOG ADVISORY AS VISIBILITIES HAVE IMPROVED
A BIT ABOVE 1/4 MILE.
FREEZING DRIZZLE BEING REPORTED...SEEMS TO BE CONFINED TO AREAS
WHERE SFC RH ABOVE 90-95 PERCENT SO HAVE INCLUDED. TO THE EAST
DRIER AIR AND HIGHER T/TD SPREADS ARE LIMITING FREEZING DRIZZLE
POTENTIAL. MAY SEE ANOTHER HOUR OR TWO OF FREEZING DRIZZLE BEFORE
THINGS COME TO AN END FOR TODAY. NOT MUCH HAS CHANGED WITH MAX
TEMPS TODAY IN THE MID 20S WITH LOW 30S ACROSS THE FAR SOUTHWEST
THROUGH WEST.
UPDATE ISSUED AT 1009 AM MST SUN FEB 23 2014
CONDITIONS HAVE NOT CHANGED OVER THE PAST HOUR AND A HALF AND 15Z
RUC CONTINUES TO SUPPORT WIDESPREAD LOW CLOUDS WITH FOG ACROSS THE
AREA FOR THE REST OF THE DAY. HAVE ADJUSTED GRIDS ACCORDINGLY. IN
THE GOODLAND AREA VISIBILITIES CONTINUE AROUND ONE QUARTER MILE
WITH WEB CAMS AND METARS AROUND THE AREA SHOWING VISIBILITIES
HIGHER. SINCE CONDITIONS ARE NOT EXPECTED TO CHANGE MUCH HAVE GONE
AHEAD AND ISSUED A DENSE FOG ADVISORY FOR SHERMAN COUNTY TIL 20Z.
MAY HAVE TO GO LONGER BUT WILL WAIT AND SEE ON THAT.
UPDATE ISSUED AT 850 AM MST SUN FEB 23 2014
ENTIRE FORECAST AREA ENTRENCHED IN STRATUS THIS MORNING WITH
EAST/NORTHEAST WINDS EAST OF THE CO/KS BORDER AND SOUTHEAST WINDS
ACROSS FAR EASTERN COLORADO. FOG ALSO BEING REPORTED ACROSS THE
WESTERN 2/3 OF THE AREA WITH LOCALLY DENSE FOG IN THE GOODLAND
AREA.
LATEST RUC HAS AN EXCELLENT GRASP OF THE STRATUS AND PER THE 12Z
RUN KEEPS IT OVER THE AREA FOR THE ENTIRE DAY. THE HRRR BREAKS UP
THE STRATUS OVER PARTS OF FAR EASTERN COLORADO BUT KEEPS IT OVER
THE REST OF THE AREA THROUGH THE DAY AS WELL. SHOULD THESE
SCENARIOS VERIFY TEMPERATURES WONT MOVE MUCH FROM WHERE THEY ARE
NOW AND WOULD BE SEVERAL DEGREES BELOW PREVIOUS FORECAST.
12Z NAM BOUNDARY LAYER RH ALSO HAD A GOOD HANDLE ON AREAL COVERAGE
OF STRATUS BUT BY 18Z LIFTS IT/DISSIPATES IT FROM SOUTH TO NORTH
ALLOWING MORE HEATING AND WARMER TEMPERATURES THAN THE RUC/HRRR.
FOR THE FIRST OF WHAT WILL LIKELY BE SEVERAL UPDATES HAVE TRENDED
TOWARD THE RUC/HRRR GIVEN THE EASTERLY COMPONENT TO THE WINDS ALL
DAY WHICH IS NOT REAL FAVORABLE FOR RAPID STRATUS DISSIPATION AS
THE NAM WOULD SUGGEST. HAVE LOWERED HIGH TEMPERATURES TO THE
MID/UPPER 20S ACROSS THE NORTHEAST AND EAST (WHERE LOW CLOUDS
EXPECTED LONGER) AND LOW TO MID 30S ACROSS THE FAR SOUTH THROUGH
SOUTHWEST AND WEST WHERE SOME DISSIPATION WOULD BE MOST LIKELY BUT
NOT CERTAIN AT THIS POINT.
HAVE ALSO BEEFED UP THE FOG PER LOCAL OBSERVATIONS. NONE OF THE
MODELS HANDLING THIS VERY WELL...HOPEFULLY THE 15Z RUC WILL LATCH
ON TO IT AND GIVE SOME BETTER GUIDANCE.
MORE UPDATES LIKELY TO COME LATER.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY NIGHT)
ISSUED AT 314 AM MST SUN FEB 23 2014
UPPER FLOW WILL BE NORTHWEST THROUGH TUESDAY NIGHT. SURFACE HIGH
PRESSURE WILL BE OVER THE REGION TODAY AND TONIGHT. HIGH PRESSURE
WILL DRIFT EAST MONDAY AS LOW PRESSURE MOVES INTO EASTERN COLORADO.
A COLD FRONT WILL PUSH SOUTH MONDAY NIGHT FOLLOWED BY HIGH PRESSURE
TUESDAY AND TUESDAY NIGHT.
CURRENT RADAR SHOWING DECREASING TREND OF SNOW RETURNS OVER THE
NORTH IN THE CURRENT WINTER WEATHER ADVISORY. FRONTOGENESIS EXITS
THE AREA AND DO NOT EXPECT ANYTHING MORE THAN LIGHT SNOW THIS
MORNING AND EVEN LESS OF AN AREA THIS AFTERNOON AS DYNAMICS MOVE OUT
OF THE AREA. PLAN TO CANCEL THE WINTER WEATHER ADVISORY AT ZONES
ISSUANCE. DEWPOINT DEPRESSIONS ARE NARROWING TO LESS THAN 3 DEGREES
AND BOUNDARY LAYER RH IS PROGGED TO INCREASE TO OVER 90 PERCENT SO
HAVE INCLUDED SOME PATCHY FREEZING FOG THIS MORNING OVER ALL BUT THE
NORTHEAST FA.
FORECAST SOUNDINGS ACROSS THE FA TONIGHT INDICATE THE POSSIBILITY OF
SOME STRATUS AND FOG BUT MOISTURE IS TOO SHALLOW TO INDICATE
FREEZING DRIZZLE. PLAN TO PULL THE FREEZING DRIZZLE AND CONSIDER
SOME MENTION OF FOG OVERNIGHT INTO MONDAY MORNING. POPS WILL BE NIL
MONDAY DUE TO SUBSIDENCE AND LACK OF MOISTURE. THERE IS SOME WEAK
FORCING ACROSS THE NORTHERN ZONES MONDAY NIGHT/TUESDAY MORNING AND
MOISTURE INCREASES SO CANNOT RULE OUT A SLIGHT CHANCE OF LIGHT SNOW
OR FLURRIES. FOR TUESDAY AFTERNOON/TUESDAY NIGHT...THE GFS IS FASTER
WITH BRINGING DYNAMICS INTO THE FA THAN THE NAM. FOR NOW WILL OPT
FOR THE GFS TO STAY CONSISTENT WITH SURROUNDING OFFICES. HOWEVER DUE
TO THE TIMING DIFFERENCES WILL KEEP POPS IN THE SLIGHT CHANCE/CHANCE
RANGE.
MAX TEMPERATURES TODAY WILL BE IN THE MID 30S EXCEPT FOR WESTERN
PORTIONS OF EASTERN COLORADO WHERE SOME LOWER 40S WILL BE POSSIBLE.
TEMPERATURES WILL WARM INTO THE 40S WITH SOME MID 50S POSSIBLE IN
THE SOUTHWEST PORTION OF THE FA. TUESDAY WILL BE COLDER BEHIND THE
FRONT WITH READINGS IN THE UPPER 20S AND LOW 30S. MIN TEMPERATURES
TONIGHT WILL FALL INTO THE LOWER 20S AND INTO THE TEENS MONDAY AND
TUESDAY NIGHTS.
.LONG TERM...(WEDNESDAY THROUGH SATURDAY)
ISSUED AT 236 AM MST SUN FEB 23 2014
A RETURN OF BELOW NORMAL TEMPERATURES WILL BE THE MAIN
CHARACTERISTIC OF THE EXTENDED FORECAST WITH A FEW PERIODS OF SNOW
POSSIBLE. MODELS INDICATE THAT NORTHWEST FLOW IS THE PRIMARY UPPER
LEVEL PATTERN ACROSS THE TRI-STATE AREA WITH A LARGE TROUGH OVER THE
EASTERN UNITED STATES AND A RIDGE TO THE WEST. WITH THIS PATTERN IN
PLACE...THE GATE IS OPEN FOR COLD CANADIAN AIR TO MOVE IN. THIS
PATTERN IS SIMILAR TO THE EXTENDED VERY COLD OUTBREAK OBSERVED
EARLIER THIS MONTH. THE COLD WEATHER IS NOT EXPECTED TO REACH THAT
EXTENT AGAIN BUT WELL BELOW NORMAL TEMPERATURES SHOULD BE EXPECTED.
THE FORECAST INITIALIZATION PROCEDURE PROVIDED TEMPERATURES THAT
SEEMED UNREASONABLY WARM FOR THIS TYPE OF PATTERN. THE EUROPEAN
SEEMS MOST REASONABLE AND IS SUPPORTED BY THE CANADIAN MODEL. THE
OPERATIONAL GFS HAS 850 MB TEMPS IN THE SAME BALLPARK AS THE
EUROPEAN HOWEVER MEX GUIDANCE IS 10 TO NEARLY 20 DEGREES WARMER FOR
FRIDAY AND SATURDAY. AS A RESULT...TEMPERATURES WERE NUDGED DOWN A
FEW DEGREES BUT FORECAST IS STILL PROBABLY TOO WARM.
AS FOR PRECIPITATION...THERE ARE TWO CHANCES AT WINTRY PRECIP DURING
THE EXTENDED PERIOD. FOR WEDNESDAY...THE UPPER LEVEL DISTURBANCE
THAT WILL BRING SNOW FOR TUESDAY NIGHT SHOULD BE CLEAR OF THE REGION
WITH HIGH PRESSURE BUILDING IN. ADVERTISED DRY CONDITIONS FOR
WEDNESDAY BUT A FEW FLURRIES MAY LINGER DEPENDING ON SPEED AND
MOVEMENT OF THIS SYSTEM. THE FIRST CHANCE FOR PRECIPITATION IN THE
EXTENDED FORECAST IS ANTICIPATED ON THURSDAY NIGHT INTO FRIDAY. THIS
CHANCE COMES AS A STRONGER DISTURBANCE IN THE NORTHWEST FLOW
TRANSITIONS ACROSS THE REGION. MODELS DISAGREE SOMEWHAT IN THE
PLACEMENT AND MOVEMENT OF THIS SYSTEM SO HAVE ONLY GONE SLIGHT
CHANCE TO LOW CHANCE POPS FOR THURSDAY NIGHT. DUE TO THE SPEED OF
THIS SYSTEM...AN EXTENDED PERIOD OF ACCUMULATING SNOW IS NOT
EXPECTED. IT IS ALSO POSSIBLE THIS SYSTEM MOVES SOUTH OF THE AREA
WITH NO SNOW AS THE BEST FORCING APPEARS TO REMAIN SOUTH.
THE SECOND...MORE SIGNIFICANT CHANCE OF PRECIPITATION COMES FOR NEXT
WEEKEND. THROUGH 00Z SATURDAY...THE EUROPEAN...CANADIAN AND GFS
MODELS ARE IN DECENT AGREEMENT ON A 500 MB LOW COMING INTO
CALIFORNIA. THE GFS AND EUROPEAN MODELS THEN BRING THIS SYSTEM
ACROSS THE ROCKIES ON SATURDAY AND INTO THE HIGH PLAINS SUNDAY.
THESE TYPES OF SYSTEMS ARE TYPICALLY RESPONSIBLE FOR LARGER SNOW
AMOUNTS SO WILL NEED TO MONITOR THIS SYSTEM CLOSELY. AS WITH ANY
EXTENDED FORECAST...MODELS CAN AND OFTEN DO CHANGE THEIR SOLUTIONS
THIS FAR OUT. HOWEVER...WITH BOTH MODELS PICKING UP ON IT AND
PROJECTING A SIMILAR SOLUTION...THIS MAY HAVE A LITTLE MORE WEIGHT
TO IT THAN A TYPICAL EXTENDED FORECAST STORM.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1031 AM MST SUN FEB 23 2014
THIS TAF PERIOD WILL BE A MESSY ONE AS A STATIONARY FRONT TO THE
WEST OF THE TRI STATE AREA WILL KEEP CONDITIONS OVERCAST THROUGH
MOST OF THE TAF PERIOD FOR BOTH TERMINALS. PINNING DOWN
VISIBILITIES FOR KGLD AND CEILING HEIGHTS FOR BOTH TERMINALS WAS A
BIT TOUGH WITH MODEL GUIDANCE DIFFERING A LOT.
REDUCED VISIBILITIES EXPECTED TO CONTINUE AT KGLD FOR THE REST OF
THE MORNING AND INTO THE EARLY AFTERNOON HOURS BEFORE CONDITIONS
IMPROVE TO MVFR. A BRIEF BREAK WILL OCCUR AROUND SUNDOWN WITH
IMPROVED CONDITIONS BEFORE OVERCAST CONDITIONS AND REDUCED
VISIBILITIES RETURN FOR OVERNIGHT.
OVERCAST CONDITIONS AT KMCK WILL CONTINUE INTO TONIGHT. SOME AREAS
OF PATCHY FOG AROUND THE TERMINAL WILL DEVELOP...SO MENTIONED MVFR
CONDITIONS FOR VISIBILITY. CONDITIONS WILL IMPROVE TO VFR BY MID
MORNING.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...99
SHORT TERM...FS
LONG TERM...RRH
AVIATION...MK
AREA FORECAST DISCUSSION
NWS WICHITA KS
1213 PM CST SUN FEB 23 2014
...UPDATED FOR AVIATION DISCUSSION...
.UPDATE...
ISSUED AT 1210 PM CST SUN FEB 23 2014
STRATUS DECK THAT COVERS NORTHERN TWO-THIRDS OF KANSAS NOT BEING
HANDLED WELL BY LARGER-SCALE MODELS...THOUGH RUC AND HRRR APPEAR
TO BE CAPTURING THE SITUATION THE BEST. PERSISTENT CLOUDS WILL HAVE
IMPACT ON TEMPERATURES AND WINDS...AND HAVE ADJUSTED BOTH
DOWNWARD...FOR NORTH CENTRAL COUNTIES IN THE CWA. RUC LOW LEVEL
RH/ISENTROPIC FIELDS SUGGESTS EDGE OF CLOUD DECK TO REMAIN NORTH
AND WEST OF WICHITA/NE I-35 CORRIDOR...SO ONLY MINOR CHANGES IN
FORECAST FOR SOUTH-CENTRAL AND SOUTHEAST PORTIONS OF THE CWA.
SF
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 343 AM CST SUN FEB 23 2014
A SHORTWAVE TROUGH WAS MOVING EAST-SOUTHEAST ACROSS THE CENTRAL
ROCKIES AND INTO THE CENTRAL PLAINS EARLY THIS MORNING WHILE AN
EXPANSIVE AREA OF MID-LEVEL FRONTOGENESIS WAS PRESENT DOWNSTREAM
ALONG THE KANSAS AND NEBRASKA STATE LINE. THIS WAS SUPPORTING A LARGE
AREA OF LIGHT SNOW WHICH IS EXPECTED TO REMAIN NORTH OF THE
FORECAST AREA BEFORE DIMINISHING TOWARD THE MIDDLE OF THE DAY. AT
THE SURFACE, A COLD FRONT WAS LOCATED ACROSS THE SOUTHERN PLAINS
WHILE NORTHEAST WINDS RESULTED IN LOW LEVEL COLD AIR ADVECTION
ACROSS ALL OF THE CENTRAL PLAINS STATES. THIS WILL RESULT IN BELOW
NORMAL TEMPERATURES RETURNING TO THE FORECAST AREA TODAY.
THE INITIAL COOL DOWN WILL BE SHORT-LIVED AS SOUTHERLY FLOW RETURNS
TO THE CENTRAL PLAINS ON MONDAY ALLOWING TEMPERATURES TO RETURN TO
SEASONABLE VALUES IN THE UPPER 40S/AROUND 50. A PROGRESSIVE
NORTHWEST MID/UPPER LEVEL FLOW REGIME WILL DRIVE ANOTHER CLIPPER
SYSTEM ACROSS THE NORTHERN PLAINS LATE MONDAY SENDING ANOTHER SURGE
OF MODIFIED ARCTIC AIR SOUTH ACROSS THE CENTRAL PLAINS INTO TUESDAY.
HIGHS MAY STRUGGLE TO REACH 30 ACROSS PORTIONS OF WESTERN AND
CENTRAL KANSAS WHILE SOUTHEAST KANSAS MAY CLIMB TO NEAR 40. A SUBTLE
SHORTWAVE TROUGH MAY ALLOW FOR A PERIOD OF LIGHT SNOW OR FLURRIES ON
TUESDAY HOWEVER CONFIDENCE REMAINS TOO LOW TO INCREASE POPS UP AT THIS
TIME. SURFACE HIGH PRESSURE WILL SETTLE OVER THE AREA TUESDAY NIGHT
ALLOWING FOR STRONG RADIATIONAL COOLING AND TRENDED LOWS DOWN WITH
VALUES IN THE TEENS ANTICIPATED.
.LONG TERM...(WEDNESDAY THROUGH SATURDAY)
ISSUED AT 343 AM CST SUN FEB 23 2014
MODERATING TEMPERATURES ARE EXPECTED WED-THU AS NORTHWEST
MID/UPPER FLOW PREVAILS ACROSS THE CENTRAL CONUS. THE MID/UPPER
RIDGE ANCHORED ACROSS THE SOUTHWEST IS PROGGED TO FLATTEN ON
THURSDAY AS A MORE VIGOROUS TROUGH MOVES OVER THE GREAT BASIN
AREA. ANOTHER COLD FRONT IS PROGGED TO MOVE SOUTH ACROSS THE
NORTHERN AND CENTRAL PLAINS ON THURSDAY BRINGING AN END TO THE
WARMING TREND ALTHOUGH THE CHANCES FOR MEASURABLE PRECIPITATION
APPEAR TO REMAIN LOW AT THIS TIME. THERE REMAINS SOME POTENTIAL
FOR LIGHT PRECIPITATION BUT HIGHER PROBABILITIES APPEAR TO REMAIN
SOUTH AND EAST OF THE AREA AND MAINTAINED A SEASONABLY COOL AND
DRY FORECAST FOR NOW.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1210 PM CST SUN FEB 23 2014
MVFR CIGS WILL LINGER AT KRSL...KSLN AND KHUT FOR HALF OR MORE OF
THE FIRST PERIOD OF THE FORECAST CYCLE. PERISTENT STRATUS DECK THAT
ENVELOPES THE NORTHERN TWO-THIRDS OF KANSAS... NOT HANDLED WELL
BY MAJORITY OF FORECAST MODELS...BUT AS MENTIONED IN UPDATE
SECTION...BOTH RUC/HRRR APPEAR TO REINITALIZED AND CAPTURED
SITUATION. LATEST VISIBLE IMAGERY SHOWING SOME BREAKS IN THE
STRATUS...BUT TRENDED TOWARD MORE PESSIMISTIC SOLUTION OF KEEPING
MVFR CIGS AT KRSL...KSLN AND KHUT THROUGH 22-23 UTC. AS SURFACE
/LOW-LEVEL FLOW VEERS TO AN EASTERLY COMPONENT AFT 00 UTC...EXPECT
CIGS TO RETREAT WEST OF AFOREMENTIONED TAF SITES. BY 06 UTC...EXPECT
VFR CIGS AND VSBYS TO PREVAIL AT ALL TERMINAL SITES. NORTHEAST WINDS
WILL VEER THROUGH THE FORECAST PERIOD...BECOMING EAST TO SOUTHEAST
BY 12 UTC/24.
SF
&&
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 44 24 49 26 / 0 0 10 10
HUTCHINSON 38 20 48 24 / 0 10 10 10
NEWTON 40 22 46 24 / 0 10 10 10
ELDORADO 44 23 47 26 / 0 0 10 10
WINFIELD-KWLD 48 24 49 28 / 0 0 10 10
RUSSELL 33 22 49 19 / 10 10 10 10
GREAT BEND 34 20 50 22 / 10 10 10 10
SALINA 35 22 46 22 / 10 10 10 10
MCPHERSON 36 22 47 24 / 10 10 10 10
COFFEYVILLE 49 23 49 31 / 0 0 10 10
CHANUTE 45 23 46 26 / 0 10 10 10
IOLA 44 24 45 25 / 0 10 10 10
PARSONS-KPPF 48 23 48 28 / 0 0 10 10
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1101 AM MST SUN FEB 23 2014
.UPDATE...
ISSUED AT 1009 AM MST SUN FEB 23 2014
CONDITIONS HAVE NOT CHANGED OVER THE PAST HOUR AND A HALF AND 15Z
RUC CONTINUES TO SUPPORT WIDESPREAD LOW CLOUDS WITH FOG ACROSS THE
AREA FOR THE REST OF THE DAY. HAVE ADJUSTED GRIDS ACCORDINGLY. IN
THE GOODLAND AREA VISIBILITIES CONTINUE AROUND ONE QUARTER MILE
WITH WEB CAMS AND METARS AROUND THE AREA SHOWING VISIBILITIES
HIGHER. SINCE CONDITIONS ARE NOT EXPECTED TO CHANGE MUCH HAVE GONE
AHEAD AND ISSUED A DENSE FOG ADVISORY FOR SHERMAN COUNTY TIL 20Z.
MAY HAVE TO GO LONGER BUT WILL WAIT AND SEE ON THAT.
UPDATE ISSUED AT 850 AM MST SUN FEB 23 2014
ENTIRE FORECAST AREA ENTRENCHED IN STRATUS THIS MORNING WITH
EAST/NORTHEAST WINDS EAST OF THE CO/KS BORDER AND SOUTHEAST WINDS
ACROSS FAR EASTERN COLORADO. FOG ALSO BEING REPORTED ACROSS THE
WESTERN 2/3 OF THE AREA WITH LOCALLY DENSE FOG IN THE GOODLAND
AREA.
LATEST RUC HAS AN EXCELLENT GRASP OF THE STRATUS AND PER THE 12Z
RUN KEEPS IT OVER THE AREA FOR THE ENTIRE DAY. THE HRRR BREAKS UP
THE STRATUS OVER PARTS OF FAR EASTERN COLORADO BUT KEEPS IT OVER
THE REST OF THE AREA THROUGH THE DAY AS WELL. SHOULD THESE
SCENARIOS VERIFY TEMPERATURES WONT MOVE MUCH FROM WHERE THEY ARE
NOW AND WOULD BE SEVERAL DEGREES BELOW PREVIOUS FORECAST.
12Z NAM BOUNDARY LAYER RH ALSO HAD A GOOD HANDLE ON AREAL COVERAGE
OF STRATUS BUT BY 18Z LIFTS IT/DISSIPATES IT FROM SOUTH TO NORTH
ALLOWING MORE HEATING AND WARMER TEMPERATURES THAN THE RUC/HRRR.
FOR THE FIRST OF WHAT WILL LIKELY BE SEVERAL UPDATES HAVE TRENDED
TOWARD THE RUC/HRRR GIVEN THE EASTERLY COMPONENT TO THE WINDS ALL
DAY WHICH IS NOT REAL FAVORABLE FOR RAPID STRATUS DISSIPATION AS
THE NAM WOULD SUGGEST. HAVE LOWERED HIGH TEMPERATURES TO THE
MID/UPPER 20S ACROSS THE NORTHEAST AND EAST (WHERE LOW CLOUDS
EXPECTED LONGER) AND LOW TO MID 30S ACROSS THE FAR SOUTH THROUGH
SOUTHWEST AND WEST WHERE SOME DISSIPATION WOULD BE MOST LIKELY BUT
NOT CERTAIN AT THIS POINT.
HAVE ALSO BEEFED UP THE FOG PER LOCAL OBSERVATIONS. NONE OF THE
MODELS HANDLING THIS VERY WELL...HOPEFULLY THE 15Z RUC WILL LATCH
ON TO IT AND GIVE SOME BETTER GUIDANCE.
MORE UPDATES LIKELY TO COME LATER.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY NIGHT)
ISSUED AT 314 AM MST SUN FEB 23 2014
UPPER FLOW WILL BE NORTHWEST THROUGH TUESDAY NIGHT. SURFACE HIGH
PRESSURE WILL BE OVER THE REGION TODAY AND TONIGHT. HIGH PRESSURE
WILL DRIFT EAST MONDAY AS LOW PRESSURE MOVES INTO EASTERN COLORADO.
A COLD FRONT WILL PUSH SOUTH MONDAY NIGHT FOLLOWED BY HIGH PRESSURE
TUESDAY AND TUESDAY NIGHT.
CURRENT RADAR SHOWING DECREASING TREND OF SNOW RETURNS OVER THE
NORTH IN THE CURRENT WINTER WEATHER ADVISORY. FRONTOGENESIS EXITS
THE AREA AND DO NOT EXPECT ANYTHING MORE THAN LIGHT SNOW THIS
MORNING AND EVEN LESS OF AN AREA THIS AFTERNOON AS DYNAMICS MOVE OUT
OF THE AREA. PLAN TO CANCEL THE WINTER WEATHER ADVISORY AT ZONES
ISSUANCE. DEWPOINT DEPRESSIONS ARE NARROWING TO LESS THAN 3 DEGREES
AND BOUNDARY LAYER RH IS PROGGED TO INCREASE TO OVER 90 PERCENT SO
HAVE INCLUDED SOME PATCHY FREEZING FOG THIS MORNING OVER ALL BUT THE
NORTHEAST FA.
FORECAST SOUNDINGS ACROSS THE FA TONIGHT INDICATE THE POSSIBILITY OF
SOME STRATUS AND FOG BUT MOISTURE IS TOO SHALLOW TO INDICATE
FREEZING DRIZZLE. PLAN TO PULL THE FREEZING DRIZZLE AND CONSIDER
SOME MENTION OF FOG OVERNIGHT INTO MONDAY MORNING. POPS WILL BE NIL
MONDAY DUE TO SUBSIDENCE AND LACK OF MOISTURE. THERE IS SOME WEAK
FORCING ACROSS THE NORTHERN ZONES MONDAY NIGHT/TUESDAY MORNING AND
MOISTURE INCREASES SO CANNOT RULE OUT A SLIGHT CHANCE OF LIGHT SNOW
OR FLURRIES. FOR TUESDAY AFTERNOON/TUESDAY NIGHT...THE GFS IS FASTER
WITH BRINGING DYNAMICS INTO THE FA THAN THE NAM. FOR NOW WILL OPT
FOR THE GFS TO STAY CONSISTENT WITH SURROUNDING OFFICES. HOWEVER DUE
TO THE TIMING DIFFERENCES WILL KEEP POPS IN THE SLIGHT CHANCE/CHANCE
RANGE.
MAX TEMPERATURES TODAY WILL BE IN THE MID 30S EXCEPT FOR WESTERN
PORTIONS OF EASTERN COLORADO WHERE SOME LOWER 40S WILL BE POSSIBLE.
TEMPERATURES WILL WARM INTO THE 40S WITH SOME MID 50S POSSIBLE IN
THE SOUTHWEST PORTION OF THE FA. TUESDAY WILL BE COLDER BEHIND THE
FRONT WITH READINGS IN THE UPPER 20S AND LOW 30S. MIN TEMPERATURES
TONIGHT WILL FALL INTO THE LOWER 20S AND INTO THE TEENS MONDAY AND
TUESDAY NIGHTS.
.LONG TERM...(WEDNESDAY THROUGH SATURDAY)
ISSUED AT 236 AM MST SUN FEB 23 2014
A RETURN OF BELOW NORMAL TEMPERATURES WILL BE THE MAIN
CHARACTERISTIC OF THE EXTENDED FORECAST WITH A FEW PERIODS OF SNOW
POSSIBLE. MODELS INDICATE THAT NORTHWEST FLOW IS THE PRIMARY UPPER
LEVEL PATTERN ACROSS THE TRI-STATE AREA WITH A LARGE TROUGH OVER THE
EASTERN UNITED STATES AND A RIDGE TO THE WEST. WITH THIS PATTERN IN
PLACE...THE GATE IS OPEN FOR COLD CANADIAN AIR TO MOVE IN. THIS
PATTERN IS SIMILAR TO THE EXTENDED VERY COLD OUTBREAK OBSERVED
EARLIER THIS MONTH. THE COLD WEATHER IS NOT EXPECTED TO REACH THAT
EXTENT AGAIN BUT WELL BELOW NORMAL TEMPERATURES SHOULD BE EXPECTED.
THE FORECAST INITIALIZATION PROCEDURE PROVIDED TEMPERATURES THAT
SEEMED UNREASONABLY WARM FOR THIS TYPE OF PATTERN. THE EUROPEAN
SEEMS MOST REASONABLE AND IS SUPPORTED BY THE CANADIAN MODEL. THE
OPERATIONAL GFS HAS 850 MB TEMPS IN THE SAME BALLPARK AS THE
EUROPEAN HOWEVER MEX GUIDANCE IS 10 TO NEARLY 20 DEGREES WARMER FOR
FRIDAY AND SATURDAY. AS A RESULT...TEMPERATURES WERE NUDGED DOWN A
FEW DEGREES BUT FORECAST IS STILL PROBABLY TOO WARM.
AS FOR PRECIPITATION...THERE ARE TWO CHANCES AT WINTRY PRECIP DURING
THE EXTENDED PERIOD. FOR WEDNESDAY...THE UPPER LEVEL DISTURBANCE
THAT WILL BRING SNOW FOR TUESDAY NIGHT SHOULD BE CLEAR OF THE REGION
WITH HIGH PRESSURE BUILDING IN. ADVERTISED DRY CONDITIONS FOR
WEDNESDAY BUT A FEW FLURRIES MAY LINGER DEPENDING ON SPEED AND
MOVEMENT OF THIS SYSTEM. THE FIRST CHANCE FOR PRECIPITATION IN THE
EXTENDED FORECAST IS ANTICIPATED ON THURSDAY NIGHT INTO FRIDAY. THIS
CHANCE COMES AS A STRONGER DISTURBANCE IN THE NORTHWEST FLOW
TRANSITIONS ACROSS THE REGION. MODELS DISAGREE SOMEWHAT IN THE
PLACEMENT AND MOVEMENT OF THIS SYSTEM SO HAVE ONLY GONE SLIGHT
CHANCE TO LOW CHANCE POPS FOR THURSDAY NIGHT. DUE TO THE SPEED OF
THIS SYSTEM...AN EXTENDED PERIOD OF ACCUMULATING SNOW IS NOT
EXPECTED. IT IS ALSO POSSIBLE THIS SYSTEM MOVES SOUTH OF THE AREA
WITH NO SNOW AS THE BEST FORCING APPEARS TO REMAIN SOUTH.
THE SECOND...MORE SIGNIFICANT CHANCE OF PRECIPITATION COMES FOR NEXT
WEEKEND. THROUGH 00Z SATURDAY...THE EUROPEAN...CANADIAN AND GFS
MODELS ARE IN DECENT AGREEMENT ON A 500 MB LOW COMING INTO
CALIFORNIA. THE GFS AND EUROPEAN MODELS THEN BRING THIS SYSTEM
ACROSS THE ROCKIES ON SATURDAY AND INTO THE HIGH PLAINS SUNDAY.
THESE TYPES OF SYSTEMS ARE TYPICALLY RESPONSIBLE FOR LARGER SNOW
AMOUNTS SO WILL NEED TO MONITOR THIS SYSTEM CLOSELY. AS WITH ANY
EXTENDED FORECAST...MODELS CAN AND OFTEN DO CHANGE THEIR SOLUTIONS
THIS FAR OUT. HOWEVER...WITH BOTH MODELS PICKING UP ON IT AND
PROJECTING A SIMILAR SOLUTION...THIS MAY HAVE A LITTLE MORE WEIGHT
TO IT THAN A TYPICAL EXTENDED FORECAST STORM.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1031 AM MST SUN FEB 23 2014
THIS TAF PERIOD WILL BE A MESSY ONE AS A STATIONARY FRONT TO THE
WEST OF THE TRI STATE AREA WILL KEEP CONDITIONS OVERCAST THROUGH
MOST OF THE TAF PERIOD FOR BOTH TERMINALS. PINNING DOWN
VISIBILITIES FOR KGLD AND CEILING HEIGHTS FOR BOTH TERMINALS WAS A
BIT TOUGH WITH MODEL GUIDANCE DIFFERING A LOT.
REDUCED VISIBILITIES EXPECTED TO CONTINUE AT KGLD FOR THE REST OF
THE MORNING AND INTO THE EARLY AFTERNOON HOURS BEFORE CONDITIONS
IMPROVE TO MVFR. A BRIEF BREAK WILL OCCUR AROUND SUNDOWN WITH
IMPROVED CONDITIONS BEFORE OVERCAST CONDITIONS AND REDUCED
VISIBILITIES RETURN FOR OVERNIGHT.
OVERCAST CONDITIONS AT KMCK WILL CONTINUE INTO TONIGHT. SOME AREAS
OF PATCHY FOG AROUND THE TERMINAL WILL DEVELOP...SO MENTIONED MVFR
CONDITIONS FOR VISIBILITY. CONDITIONS WILL IMPROVE TO VFR BY MID
MORNING.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...DENSE FOG ADVISORY UNTIL 1 PM MST THIS AFTERNOON FOR KSZ013.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...99
SHORT TERM...FS
LONG TERM...RRH
AVIATION...MK
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1011 AM MST SUN FEB 23 2014
.UPDATE...
ISSUED AT 1009 AM MST SUN FEB 23 2014
CONDITIONS HAVE NOT CHANGED OVER THE PAST HOUR AND A HALF AND 15Z
RUC CONTINUES TO SUPPORT WIDESPREAD LOW CLOUDS WITH FOG ACROSS THE
AREA FOR THE REST OF THE DAY. HAVE ADJUSTED GRIDS ACCORDINGLY. IN
THE GOODLAND AREA VISIBILITIES CONTINUE AROUND ONE QUARTER MILE
WITH WEB CAMS AND METARS AROUND THE AREA SHOWING VISIBILITIES
HIGHER. SINCE CONDITIONS ARE NOT EXPECTED TO CHANGE MUCH HAVE GONE
AHEAD AND ISSUED A DENSE FOG ADVISORY FOR SHERMAN COUNTY TIL 20Z.
MAY HAVE TO GO LONGER BUT WILL WAIT AND SEE ON THAT.
UPDATE ISSUED AT 850 AM MST SUN FEB 23 2014
ENTIRE FORECAST AREA ENTRENCHED IN STRATUS THIS MORNING WITH
EAST/NORTHEAST WINDS EAST OF THE CO/KS BORDER AND SOUTHEAST WINDS
ACROSS FAR EASTERN COLORADO. FOG ALSO BEING REPORTED ACROSS THE
WESTERN 2/3 OF THE AREA WITH LOCALLY DENSE FOG IN THE GOODLAND
AREA.
LATEST RUC HAS AN EXCELLENT GRASP OF THE STRATUS AND PER THE 12Z
RUN KEEPS IT OVER THE AREA FOR THE ENTIRE DAY. THE HRRR BREAKS UP
THE STRATUS OVER PARTS OF FAR EASTERN COLORADO BUT KEEPS IT OVER
THE REST OF THE AREA THROUGH THE DAY AS WELL. SHOULD THESE
SCENARIOS VERIFY TEMPERATURES WONT MOVE MUCH FROM WHERE THEY ARE
NOW AND WOULD BE SEVERAL DEGREES BELOW PREVIOUS FORECAST.
12Z NAM BOUNDARY LAYER RH ALSO HAD A GOOD HANDLE ON AREAL COVERAGE
OF STRATUS BUT BY 18Z LIFTS IT/DISSIPATES IT FROM SOUTH TO NORTH
ALLOWING MORE HEATING AND WARMER TEMPERATURES THAN THE RUC/HRRR.
FOR THE FIRST OF WHAT WILL LIKELY BE SEVERAL UPDATES HAVE TRENDED
TOWARD THE RUC/HRRR GIVEN THE EASTERLY COMPONENT TO THE WINDS ALL
DAY WHICH ISNT REAL FAVORABLE FOR RAPID STRATUS DISSIPATION AS THE
NAM WOULD SUGGEST. HAVE LOWERED HIGH TEMPERATURES TO THE MID/UPPER
20S ACROSS THE NORTHEAST AND EAST (WHERE LOW CLOUDS EXPECTED
LONGER) AND LOW TO MID 30S ACROSS THE FAR SOUTH THROUGH SOUTHWEST
AND WEST WHERE SOME DISSIPATION WOULD BE MOST LIKELY BUT NOT
CERTAIN AT THIS POINT.
HAVE ALSO BEEFED UP THE FOG PER LOCAL OBSERVATIONS. NONE OF THE
MODELS HANDLING THIS VERY WELL...HOPEFULLY THE 15Z RUC WILL LATCH
ON TO IT AND GIVE SOME BETTER GUIDANCE.
MORE UPDATES LIKELY TO COME LATER.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY NIGHT)
ISSUED AT 314 AM MST SUN FEB 23 2014
UPPER FLOW WILL BE NORTHWEST THROUGH TUESDAY NIGHT. SURFACE HIGH
PRESSURE WILL BE OVER THE REGION TODAY AND TONIGHT. HIGH PRESSURE
WILL DRIFT EAST MONDAY AS LOW PRESSURE MOVES INTO EASTERN COLORADO.
A COLD FRONT WILL PUSH SOUTH MONDAY NIGHT FOLLOWED BY HIGH PRESSURE
TUESDAY AND TUESDAY NIGHT.
CURRENT RADAR SHOWING DECREASING TREND OF SNOW RETURNS OVER THE
NORTH IN THE CURRENT WINTER WEATHER ADVISORY. FRONTOGENESIS EXITS
THE AREA AND DO NOT EXPECT ANYTHING MORE THAN LIGHT SNOW THIS
MORNING AND EVEN LESS OF AN AREA THIS AFTERNOON AS DYNAMICS MOVE OUT
OF THE AREA. PLAN TO CANCEL THE WINTER WEATHER ADVISORY AT ZONES
ISSUANCE. DEWPOINT DEPRESSIONS ARE NARROWING TO LESS THAN 3 DEGREES
AND BOUNDARY LAYER RH IS PROGGED TO INCREASE TO OVER 90 PERCENT SO
HAVE INCLUDED SOME PATCHY FREEZING FOG THIS MORNING OVER ALL BUT THE
NORTHEAST FA.
FORECAST SOUNDINGS ACROSS THE FA TONIGHT INDICATE THE POSSIBILITY OF
SOME STRATUS AND FOG BUT MOISTURE IS TOO SHALLOW TO INDICATE
FREEZING DRIZZLE. PLAN TO PULL THE FREEZING DRIZZLE AND CONSIDER
SOME MENTION OF FOG OVERNIGHT INTO MONDAY MORNING. POPS WILL BE NIL
MONDAY DUE TO SUBSIDENCE AND LACK OF MOISTURE. THERE IS SOME WEAK
FORCING ACROSS THE NORTHERN ZONES MONDAY NIGHT/TUESDAY MORNING AND
MOISTURE INCREASES SO CANNOT RULE OUT A SLIGHT CHANCE OF LIGHT SNOW
OR FLURRIES. FOR TUESDAY AFTERNOON/TUESDAY NIGHT...THE GFS IS FASTER
WITH BRINGING DYNAMICS INTO THE FA THAN THE NAM. FOR NOW WILL OPT FOR
THE GFS TO STAY CONSISTENT WITH SURROUNDING OFFICES. HOWEVER DUE TO
THE TIMING DIFFERENCES WILL KEEP POPS IN THE SLIGHT CHANCE/CHANCE
RANGE.
MAX TEMPERATURES TODAY WILL BE IN THE MID 30S EXCEPT FOR WESTERN
PORTIONS OF EASTERN COLORADO WHERE SOME LOWER 40S WILL BE POSSIBLE.
TEMPERATURES WILL WARM INTO THE 40S WITH SOME MID 50S POSSIBLE IN
THE SOUTHWEST PORTION OF THE FA. TUESDAY WILL BE COLDER BEHIND THE
FRONT WITH READINGS IN THE UPPER 20S AND LOW 30S. MIN TEMPERATURES
TONIGHT WILL FALL INTO THE LOWER 20S AND INTO THE TEENS MONDAY AND
TUESDAY NIGHTS.
.LONG TERM...(WEDNESDAY THROUGH SATURDAY)
ISSUED AT 236 AM MST SUN FEB 23 2014
A RETURN OF BELOW NORMAL TEMPERATURES WILL BE THE MAIN
CHARACTERISTIC OF THE EXTENDED FORECAST WITH A FEW PERIODS OF SNOW
POSSIBLE. MODELS INDICATE THAT NORTHWEST FLOW IS THE PRIMARY UPPER
LEVEL PATTERN ACROSS THE TRI-STATE AREA WITH A LARGE TROUGH OVER THE
EASTERN UNITED STATES AND A RIDGE TO THE WEST. WITH THIS PATTERN IN
PLACE...THE GATE IS OPEN FOR COLD CANADIAN AIR TO MOVE IN. THIS PATTERN
IS SIMILAR TO THE EXTENDED VERY COLD OUTBREAK OBSERVED EARLIER THIS
MONTH. THE COLD WEATHER IS NOT EXPECTED TO REACH THAT EXTENT AGAIN
BUT WELL BELOW NORMAL TEMPERATURES SHOULD BE EXPECTED. THE FORECAST
INITIALIZATION PROCEDURE PROVIDED TEMPERATURES THAT SEEMED
UNREASONABLY WARM FOR THIS TYPE OF PATTERN. THE EUROPEAN SEEMS MOST
REASONABLE AND IS SUPPORTED BY THE CANADIAN MODEL. THE OPERATIONAL
GFS HAS 850 MB TEMPS IN THE SAME BALLPARK AS THE EUROPEAN HOWEVER
MEX GUIDANCE IS 10 TO NEARLY 20 DEGREES WARMER FOR FRIDAY AND
SATURDAY. AS A RESULT...TEMPERATURES WERE NUDGED DOWN A FEW DEGREES
BUT FORECAST IS STILL PROBABLY TOO WARM.
AS FOR PRECIPITATION...THERE ARE TWO CHANCES AT WINTRY PRECIP DURING
THE EXTENDED PERIOD. FOR WEDNESDAY...THE UPPER LEVEL DISTURBANCE
THAT WILL BRING SNOW FOR TUESDAY NIGHT SHOULD BE CLEAR OF THE REGION
WITH HIGH PRESSURE BUILDING IN. ADVERTISED DRY CONDITIONS FOR
WEDNESDAY BUT A FEW FLURRIES MAY LINGER DEPENDING ON SPEED AND
MOVEMENT OF THIS SYSTEM. THE FIRST CHANCE FOR PRECIPITATION IN THE
EXTENDED FORECAST IS ANTICIPATED ON THURSDAY NIGHT INTO FRIDAY. THIS
CHANCE COMES AS A STRONGER DISTURBANCE IN THE NORTHWEST FLOW
TRANSITIONS ACROSS THE REGION. MODELS DISAGREE SOMEWHAT IN THE
PLACEMENT AND MOVEMENT OF THIS SYSTEM SO HAVE ONLY GONE SLIGHT
CHANCE TO LOW CHANCE POPS FOR THURSDAY NIGHT. DUE TO THE SPEED OF
THIS SYSTEM...AN EXTENDED PERIOD OF ACCUMULATING SNOW IS NOT
EXPECTED. IT IS ALSO POSSIBLE THIS SYSTEM MOVES SOUTH OF THE AREA
WITH NO SNOW AS THE BEST FORCING APPEARS TO REMAIN SOUTH.
THE SECOND...MORE SIGNIFICANT CHANCE OF PRECIPITATION COMES FOR NEXT
WEEKEND. THROUGH 00Z SATURDAY...THE EUROPEAN...CANADIAN AND GFS
MODELS ARE IN DECENT AGREEMENT ON A 500 MB LOW COMING INTO
CALIFORNIA. THE GFS AND EUROPEAN MODELS THEN BRING THIS SYSTEM
ACROSS THE ROCKIES ON SATURDAY AND INTO THE HIGH PLAINS SUNDAY. THESE
TYPES OF SYSTEMS ARE TYPICALLY RESPONSIBLE FOR LARGER SNOW AMOUNTS
SO WILL NEED TO MONITOR THIS SYSTEM CLOSELY. AS WITH ANY EXTENDED
FORECAST...MODELS CAN AND OFTEN DO CHANGE THEIR SOLUTIONS THIS FAR
OUT. HOWEVER...WITH BOTH MODELS PICKING UP ON IT AND PROJECTING A
SIMILAR SOLUTION...THIS MAY HAVE A LITTLE MORE WEIGHT TO IT THAN A
TYPICAL EXTENDED FORECAST STORM.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 438 AM MST SUN FEB 23 2014
SOME IFR AND LIFR CONDITIONS WILL CONTINUE THIS MORNING AT KGLD AND KMCK
BEHIND AN EXITING SHORTWAVE. CONDITIONS SHOULD IMPROVE TO MVFR AT
KGLD THIS AFTERNOON BUT WILL DROP BACK DOWN TO IFR TONIGHT AS FOG
AND STRATUS OVERTAKE THE AREA.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...DENSE FOG ADVISORY FROM 6 PM TO 7 PM MST THIS EVENING FOR KSZ013.
DENSE FOG ADVISORY UNTIL 1 PM MST THIS AFTERNOON FOR KSZ013.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...99
SHORT TERM...FS
LONG TERM...RRH
AVIATION...FS
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
259 PM EST SUN FEB 23 2014
.SYNOPSIS...
A COLD FRONT WILL CROSS THIS EVENING BRINGING LIGHT RAIN AND
LIGHT SNOW TO LOCATIONS SOUTH OF INTERSTATE 70. COLD WEATHER IS
PREDICTED FOR MOST OF THE WEEK WITH A RETURN OF ARCTIC AIR. NO
SIGNIFICANT SNOW ACCUMULATION IS FORECAST THIS WEEK.
&&
.NEAR TERM /THROUGH MONDAY/...
SURFACE TROUGH AXIS CONTINUES TO HAVE A TOUGH TIME SQUEEZING OUT
MOISTURE. STILL FEEL WITH APPROACHING S/W TROUGH AND PASSAGE OF
LOWER TROPOPAUSE HEIGHTS THAT LIGHT ACTIVITY IS A GOOD BET FOR A
3-5 HR WINDOW. TIGHTENED UP POP GRADIENT AND MAINTAINED LIGHT
RA/SN QUALIFIER FOR LOCATIONS S OF I-70. USED HRRR TO PINPOINT
HIGHEST POPS OF 22-03Z. QPF AMOUNTS WILL BE A FEW HUNDREDTHS AND
EVEN WITH SNOW RATIOS HIGHER THAN CLIMO STILL THINK ANY LOCATION
WILL BE HARD PRESSED TO GET MORE THAN AN INCH.
A BREAK IN THE WEATHER OVERNIGHT THROUGH MOST OF MONDAY AS WE
AWAIT MID LVL HEIGHT FALLS AND ACCOMPANYING MID LVL IMPULSE TO
INVADE FROM THE N. CHC POPS N OF I-80 AT THIS TIME SEEM PRUDENT
GIVEN QUESTIONABLE MOISTURE ESPECIALLY WITH A FROZEN LAKE ERIE.
WINDS WILL BE THE MAIN STORY MONDAY WITH GUSTS ECLIPSING 20 MPH IN
THE AFTERNOON.
ICE JAMS REMAIN A CONCERN. WITH TEMPERATURES FALLING BELOW
FREEZING THIS EVENING AND CONTINUING THE NEXT SEVERAL DAYS THE
THREAT OF ICE JAM FLOODING WILL DECREASE. ONLY TO AGAIN BE RE-
VISITED IN MARCH WHEN WE WARM WELL ABOVE FREEZING.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
LOW CONFIDENCE IN THE SHORT TERM PERIOD WITH SEVERAL ROUNDS OF SNOW
SHOWERS POSSIBLE TUES AND THEN AGAIN WEDS. MODELS STILL HAVING A
DIFFICULT TIME IN HANDLING THESE SHORTWAVES...ESPECIALLY THE WEDS
SYSTEM. THE NAM/GFS IS A LITTLE SLOWER AND LESS PROGRESSIVE THAN THE
SREF/ECMWF SOLNS. STICKING WITH MORE OF A BLEND THAN DETERMINISTIC
APPROACH WITH THIS UPDATE...LIMITING SNOW SHOWER PROBABILITIES TO
THE CHC RANGE.
WITH OUR AREA REMAINING UNDER THE INFLUENCE OF THE BROAD TROUGH OVER
THE ERN CONUS...NW FLOW ALOFT WILL KEEP TEMPERATURES COLDER THAN
AVERAGE. WILL REMAIN ON THE COLDER SIDE OF GUIDANCE THROUGH MIDWEEK.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
WINTER CONTINUES IN THE LONG TERM. ONCE AGAIN...ARCTIC AIR WILL
SETTLE IN THE EAST FOR THE SECOND HALF OF THE WEEK. REALLY NO
SYSTEMS TO HIT ON FOR PRECIP...JUST THE CROSSING OF A WEAK FRONT
THURSDAY.
&&
.AVIATION /20Z SUNDAY THROUGH FRIDAY/...
HIGH CONFIDENCE FORECAST.
VFR CONDITIONS WILL CONTINUE THROUGH THE NEXT 24 HOURS...SAVE FOR
BVI WHERE BKN STRATOCU WILL OCCUR THROUGH THE EARLY AFTERNOON. A
COLD FRONT WILL CROSS THE REGION WITH LITTLE FAN FAR AT AREA
TERMINALS. MOST LIKELY IMPACTED LOCATIONS ARE MGW/LBE WHERE VFR
-RASN COULD OCCUR BTWN 20Z-0Z.
TONIGHT ALL TERMINALS RETURN TO VFR UNDER A BKN MID DECK WHICH
WILL YIELD TO SCT CI. WINDS WILL INCREASE MONDAY MORNING WITH THE
APPROACH OF AN UPPER AIR SYSTEM DIVING DOWN FROM THE GREAT LAKES.
GUSTS COULD EXCEED 20KTS AT FKL AND DUJ.
.OUTLOOK..../18Z MONDAY THROUGH FRIDAY/...
THE PASSING OF A STRONG UPPER AIR DISTURBANCE TUESDAY NIGHT INTO
WEDNESDAY WILL BRING RESTRICTIONS.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
229 PM EST SUN FEB 23 2014
.SYNOPSIS...
A COLD FRONT WILL CROSS THIS EVENING BRINGING LIGHT RAIN AND
LIGHT SNOW TO LOCATIONS SOUTH OF INTERSTATE 70. COLD WEATHER IS
PREDICTED FOR MOST OF THE WEEK WITH A RETURN OF ARCTIC AIR. NO
SIGNIFICANT SNOW ACCUMULATION IS FORECAST THIS WEEK.
&&
.NEAR TERM /THROUGH MONDAY/...
SURFACE TROUGH AXIS CONTINUES TO HAVE A TOUGH TIME SQUEEZING OUT
MOISTURE. STILL FEEL WITH APPROACHING S/W TROUGH AND PASSAGE OF
LOWER TROPOPAUSE HEIGHTS THAT LIGHT ACTIVITY IS A GOOD BET FOR A
3-5 HR WINDOW. TIGHTENED UP POP GRADIENT AND MAINTAINED LIGHT
RA/SN QUALIFIER FOR LOCATIONS S OF I-70. USED HRRR TO PINPOINT
HIGHEST POPS OF 22-03Z. QPF AMOUNTS WILL BE A FEW HUNDREDTHS AND
EVEN WITH SNOW RATIOS HIGHER THAN CLIMO STILL THINK ANY LOCATION
WILL BE HARD PRESSED TO GET MORE THAN AN INCH.
A BREAK IN THE WEATHER OVERNIGHT THROUGH MOST OF MONDAY AS WE
AWAIT MID LVL HEIGHT FALLS AND ACCOMPANYING MID LVL IMPULSE TO
INVADE FROM THE N. CHC POPS N OF I-80 AT THIS TIME SEEM PRUDENT
GIVEN QUESTIONABLE MOISTURE ESPECIALLY WITH A FROZEN LAKE ERIE.
WINDS WILL BE THE MAIN STORY MONDAY WITH GUSTS ECLIPSING 20 MPH IN
THE AFTERNOON.
ICE JAMS REMAIN A CONCERN. WITH TEMPERATURES FALLING BELOW
FREEZING THIS EVENING AND CONTINUING THE NEXT SEVERAL DAYS THE
THREAT OF ICE JAM FLOODING WILL DECREASE. ONLY TO AGAIN BE RE-
VISITED IN MARCH WHEN WE WARM WELL ABOVE FREEZING.
&&
.SHORT TERM /MONDAY NIGHT THROUGH TUESDAY/...
LOW CONFIDENCE FOR TUESDAY`S FORECAST DUE TO DIFFERING MODEL
SOLUTIONS WITH ANOTHER UPPER LEVEL WAVE. WILL GO WITH A MIDDLE OF
THE ROAD FORECAST...MEANING CHANCE POPS FOR SNOW SHOWERS.
AREA WILL BE WELL BACK INTO THE COLD PATTERN BY TUESDAY.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
WINTER CONTINUES IN THE LONG TERM. ONCE AGAIN...ARCTIC AIR WILL
SETTLE IN THE EAST FOR THE SECOND HALF OF THE WEEK. REALLY NO
SYSTEMS TO HIT ON FOR PRECIP...JUST THE CROSSING OF A WEAK FRONT
THURSDAY.
&&
.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
HIGH CONFIDENCE FORECAST.
VFR CONDITIONS WILL CONTINUE THROUGH THE NEXT 24 HOURS...SAVE FOR
BVI WHERE BKN STRATOCU WILL OCCUR THROUGH THE EARLY AFTERNOON. A
COLD FRONT WILL CROSS THE REGION WITH LITTLE FAN FAR AT AREA
TERMINALS. MOST LIKELY IMPACTED LOCATIONS ARE MGW/LBE WHERE VFR
-RASN COULD OCCUR BTWN 20Z-0Z.
TONIGHT ALL TERMINALS RETURN TO VFR UNDER A BKN MID DECK WHICH
WILL YIELD TO SCT CI. WINDS WILL INCREASE MONDAY MORNING WITH THE
APPROACH OF AN UPPER AIR SYSTEM DIVING DOWN FROM THE GREAT LAKES.
GUSTS COULD EXCEED 20KTS AT FKL AND DUJ.
.OUTLOOK..../18Z MONDAY THROUGH FRIDAY/...
THE PASSING OF A STRONG UPPER AIR DISTURBANCE TUESDAY NIGHT INTO
WEDNESDAY WILL BRING RESTRICTIONS.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
439 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 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1248 PM EST SUN FEB 23 2014
COLD AIR AND INCREASING MOISTURE ROTATING AROUND A LOW PRESSURE
SYSTEM NEAR HUDSON BAY WILL LEAD TO CONTINUED GUSTY WESTERLY WINDS
THIS AFTERNOON. WITH SOME OPEN WATER OVER WESTERN LAKE
SUPERIOR...LAKE EFFECT SNOW SHOWERS HAVE BEEN OCCURRING IN THE WEST
WIND SNOW BELTS AND LARGELY AFFECTING KCMX FOR MUCH OF THIS
AFTERNOON. BUT AS A WEAK TROUGH MOVES THROUGH LATE THIS AFTERNOON
AND DURING THE EVENING...EXPECT WINDS TO TURN MORE FAVORABLE FOR
LAKE EFFECT AT KIWD AND HAVE LOWER VISIBILITIES. BUT THIS TURN IN
THE WINDS COULD INFLUENCE KCMX SNOWFALL...AS THERE WILL BE MORE OF
AN ICE SHADOW DUE TO THE INCREASED ICE NEAR ISLE ROYALE. MAINLY
IMPROVED VISIBILITIES DUE TO THE WEAKENING WINDS AND IF ICE
COVERAGE IS LESS THAN EXPECTED...VISIBILITIES MAY BE LOWER THAN
EXPECTED. AN APPROACHING HIGH PRESSURE RIDGE ON MONDAY AFTERNOON
MAY LEAD TO AN IMPROVEMENT IN CONDITIONS AT KIWD/KCMX LATE IN THE
TAF PERIOD.
AT KSAW...WEST TO NORTHWEST FLOW ISN/T TOO FAVORABLE FOR LESS THAN
VFR CONDITIONS FROM LAKE EFFECT BUT WITH THE EXPECTED INCREASE IN
MOISTURE WITH THE TROUGH DID LOWER TO MVFR CEILINGS AS THE TROUGH
MOVES THROUGH. HAVE A FEELING THE DOWNSLOPING FLOW WILL LEAD TO
VALUES RIGHT ON THE EDGE OF VFR/MVFR.
&&
.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...SRF
MARINE...SRF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON MS
1129 AM CST SUN FEB 23 2014
.UPDATE...CHANCES FOR SHOWERS AND ISOLATED THUNDERSTORMS WILL CONTINUE
TODAY FOR MAINLY THE SE CWA. WILL LEAVE THE FLASH FLOOD WATCH IN
EFFECT FOR THE EXTREME SE CWA AS LATEST HIRES MODELS INDICATE A QUICK
INCH OF RAIN COULD BE POSSIBLE. TEMPERATURES LATE THIS AM WERE MAINLY
IN THE UPPER 50S TO AROUND 60. HIGH TEMPS THIS AFTERNOON WILL BE
PLEASANT...MAINLY IN THE LOWER 70S. THE ONLY CHANGES TO THE CURRENT
FORECAST WERE TO CUT POPS SOME FOR TODAY ACROSS THE CENTRAL AND
PORTIONS OF THE SOUTHERN CWA...AND TO ADJUST THE HOURLY TEMPS TO
ACCOUNT FOR THE LATEST TRENDS. /27/
&&
.AVIATION...MVFR CIG WL LIKELY IMPACT AREAS ALONG/S OF I-20 THIS
MORNING BEFORE VFR CIG TRY AND RETURN AFTER 15Z OR SO. ONLY
EXCEPTION MAY VERY WELL BE NEAR HBG/PIB WHERE PERSISTENT SHRA/TSRA
BRING AT LEAST INTERMITTENT MVFR/IFR CIG AND VSBY THRU MOST OF THE
DAYLIGHT HRS. THE HEAVY RAINS NEAR HBG/PIB WL COME TO AN END BY
EARLY EVENING AS THIS ACTIVITY PUSHES E. A COLD FRONT WL START
CROSSING THE ARKLAMISS FROM THE N AROUND 22Z PASSING THRU THE
PIB/HBG AREA AROUND 06-08Z TONIGHT. NLY WINDS WL BECOME A BIT GUSTY
IN WAKE OF THE FRONT...BUT LIGHTER WINDS WL RETURN DURING THE DAY
MON. /BK/15/
&&
.PREV DISCUSSION... /ISSUED 400 AM CST SUN FEB 23 2014/
SHORT TERM...TODAY THROUGH MONDAY NIGHT...LOW LEVEL WARM/MOIST
ADVECTION IS UNDERWAY ALONG THE GULF COAST THIS MORNING EVIDENT BY
INCREASING COVERAGE OF SHOWER AND THUNDERSTORM ACTIVITY ACROSS
EASTERN LA/SOUTHERN MS. FURTHER NORTH...AN ADVANCING COLD FRONT IS
ANALYZED ON THE NORTHERN FRINGES OF THE TN VALLEY WHICH IS PROGGED
TO CROSS THE ARKLAMISS STARTING LATE THIS AFTERNOON. PRIMARY CONCERN
FOR TODAY IS THE RISK FOR HEAVY RAINS ALONG THE HWY 98
CORRIDOR...AND THUNDERSTORMS THAT COULD PRODUCE SOME NICKEL TO
QUARTER SIZE HAIL ALONG AND SOUTH OF HWY 84. 00Z NMM/ARW/LOCAL WRF
OUTPUT SHOW THE AFOREMENTIONED SHOWER/THUNDER ACTIVITY EXPANDING
INTO SOUTHERN ZONES BY MID MORNING AND GRADUALLY COMING TO AN END BY
LATE AFTERNOON/EARLY EVENING.
THE GUIDANCE HAS BEEN CONSISTENT SHOWING MID LEVEL LAPSE RATES
CLIMBING INTO THE 6.5-7.5C/KM RANGE SOUTH OF I-20 AS THE LOW LEVEL
WARM AIR SURGES IN...WITH SHOWALTER INDICES IN THE -2 TO -4C RANGE
INDICATIVE OF ELEVATED CONVECTION POTENTIAL GIVEN RELATIVELY COOL
PBL PER BUFR SOUNDINGS. WHILE LOW LEVEL WINDS LOOK TO VEER WESTERLY
BY DAYBREAK...A PASSING MID/UPPER LEVEL JET STREAK JUST TO OUR NORTH
WILL PROVIDE NEEDED ASCENT FOR CONVECTION AS THE RIGHT ENTRANCE
REGION OF THIS FEATURE PASSES. A FEW DEEPER THUNDERSTORM CORES SEEM
REASONABLE GIVEN THE SYNOPTIC SETUP AND WILL KEEP THE MENTION OF
SOME QUARTER SIZE HAIL IN THE HWO FOR TODAY.
OF EQUAL (IF NOT GREATER) CONCERN IS THE POTENTIAL FOR SOME LOCALLY
HIGH RAINFALL TOTALS ALONG HWY 98 COME LATE AFTERNOON. LOCAL WRF
OUTPUT SHOWS A SWATH OF 3-5 INCHES ACROSS MARION/LAMAR/FORREST
COUNTIES BETWEEN 12Z AND 22Z...WHILE THE HI-RES NMM/ARW SHOW
SIMILARLY ALARMING TOTALS OF ANYWHERE FROM 2-4 INCHES DURING THE
SAME TIME. GIVEN PW VALUES CLIMBING NEAR/JUST ABOVE 1.5 IN ACROSS
THIS AREA BY MID DAY (RIGHT AT THE 99TH PERCENTILE FOR FEB) AND THE
CONVECTIVE NATURE OF THE ACTIVITY THESE KINDS OF TOTALS SEEM QUITE
REASONABLE. THE BIGGEST QUESTION MARK IS JUST WHERE IS THE HEAVIEST
AXIS GOING TO SET UP. THE HRRR HAS BEEN TOYING WITH THE BEST AXIS
REMAINING CLOSER TO THE COAST ON A FEW RUNS...BUT SHOWS 2-3 IN
ALONG/SOUTH OF HWY 98 ON OTHERS. GIVEN THE HEAVY RAINS WE SAW ACROSS
THIS AREA A COUPLE DAYS AGO AND THE COINCIDENT HEAVY RAIN AXIS SHOWN
IN THE HI-RES ARW/NMM/LOCAL WRF FEEL THE RISK FOR FLASH FLOODING IS
GREAT ENOUGH TO WARRANT A FLASH FLOOD WATCH THROUGH 22Z. BY EARLY
EVENING THE BETTER FORCING WILL SHIFT EAST WHICH WILL SHUNT DEEPER
CONVECTION AND ASSOCIATED HEAVY RAIN RISK EAST AS WELL.
OTHER THAN SOME LIGHT SHOWER ACTIVITY SOUTH OF I-20 THE OVERNIGHT
HOURS LOOK PRETTY QUIET AS THE COLD FRONT CROSSES THE REGION. QUIET
CONDITIONS LOOK TO PREVAIL THROUGH MONDAY NIGHT...ALTHOUGH IT`S NOT
COMPLETELY OUT OF THE QUESTION THAT A FEW LIGHT SHOWERS COULD
DEVELOP ACROSS THE DELTA EARLY TUE MORNING AS A JET STREAK IN THE
PERSISTENT WESTERLY FLOW ALOFT NOSES IN. AS FOR TEMPS/POPS...LOWERED
MAV GUIDANCE FOR THIS AFTERNOON ACROSS SOUTHEASTERN AREAS GIVEN THE
HIGH CHANCES FOR RAIN/CLOUDS THROUGH THE DAY. ALSO RAISED OVERNIGHT
LOWS FOR TUE MORNING TOWARD THE WARMER NAM/ECMWF MOS NUMBERS AND RAW
GFS OUTPUT. POPS FOR TODAY WERE RAISED QUITE A BIT NEAR HBG. /BK/
LONG TERM...TUESDAY THROUGH SUNDAY...BELOW NORMAL TEMPERATURES ARE
EXPECTED FOR THE WORK WEEK WITH NEAR NORMAL TEMPERATURES RETURNING
FOR THE WEEKEND. RAIN WILL SPREAD ACROSS THE CWA TUESDAY ASSOCIATED
WITH A SFC LOW OVER THE SOUTHERN PLAINS AND A COLD FRONT DROPPING
THROUGH THE REGION. THE ECMWF CONTINUES TO GENERATE MORE RAINFALL
THAN MODEL CONSENSUS WOULD SUGGEST OVER THE SOUTHERN PORTION OF OUR
CWA WHERE MORE THAN AN INCH TOTAL COULD FALL BY WEDNESDAY MORNING.
THE ARCTIC AIR WILL BE FILTERING INTO OUR CWA TUESDAY NIGHT AS THE
RAIN ENDS FROM THE NORTHWEST. THE LIGHT RAIN LOOKS TO MIX WITH OR
BRIEFLY CHANGE OVER TO LIGHT SNOW BEFORE ENDING EARLY WEDNESDAY
MORNING ALONG THE HIGHWAY 82 CORRIDOR. TEMPERATURES WILL REMAIN
ABOVE FREEZING AND BOTTOM OUT IN THE MID 30S ALONG THE HIGHWAY 82
CORRIDOR SO NO ACCUMULATION ON ROADWAYS IS CURRENTLY ANTICIPATED. NO
SIGNIFICANT PRECIPITATION IS EXPECTED AFTER SUNRISE WEDNESDAY. THE
STRONG CAA WILL HOLD HIGH TEMPERATURES IN THE 40S ACROSS MUCH OF THE
NORTHERN HALF OF THE AREA. THE ASSOCIATED SURFACE HIGH WILL BECOME
CENTERED OVER OUR CWA WEDNESDAY NIGHT AND THEN SHIFT EAST OF OUR CWA
THURSDAY AFTERNOON. THIS WILL SET UP THE COLDEST MORNING OF THE
FORECAST PERIOD THURSDAY MORNING WHERE LOWER 20S WILL BE COMMON IN
THE NORTH TO AROUND 30 DEGREES IN THE SOUTH. DRY WEATHER WILL
CONTINUE THURSDAY BUT A DISTURBANCE WILL DROP OVER THE SOUTHERN
PLAINS THURSDAY NIGHT AND HELP DEVELOP A SURFACE LOW. WAA AHEAD OF
THIS SYSTEM WILL BRING RAIN BACK INTO OUR WESTERN ZONES THURSDAY
NIGHT. THE ECMWF IS FASTER THAN THE GFS AND ENSEMBLES BUT CONSENSUS
BRINGS THE SHORTWAVE AND SFC LOW OVER OUR WESTERN ZONES BY FRIDAY
EVENING AND SHIFT THE SYSTEM EAST OF OUR CWA SATURDAY. DRY WEATHER
LOOKS TO RETURN SATURDAY AND LAST THROUGH MUCH OF SUNDAY. ANOTHER
DISTURBANCE WILL DROP OVER THE SOUTHERN PLAINS SUNDAY AND INCREASE
OUR RAIN CHANCES AGAIN SUNDAY NIGHT. /22/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 73 46 60 48 / 13 13 0 5
MERIDIAN 74 47 63 46 / 20 13 0 6
VICKSBURG 73 44 58 47 / 13 11 0 5
HATTIESBURG 70 55 67 50 / 89 16 0 9
NATCHEZ 70 49 59 49 / 20 17 0 7
GREENVILLE 69 36 55 42 / 7 7 0 7
GREENWOOD 74 38 55 43 / 8 8 0 4
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...FLASH FLOOD WATCH UNTIL 4 PM CST THIS AFTERNOON FOR MSZ072>074.
LA...NONE.
AR...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS BILLINGS MT
228 PM MST SUN FEB 23 2014
.SHORT TERM...VALID FOR MON AND TUE...
ONLY MINOR CHANGES IN THE SHORT TERM FORECAST AS THE WINTER STORM
FOR THE AREA REMAINS RIGHT ON TRACK.
SO FAR THIS AFTERNOON...THE STORM IS EVOLVING AS EXPECTED. THE
OVERRUNNING PATTERN SETUP EARLY THIS MORNING AS HAS BEEN RESULTING
IN STEADY LIGHT SNOW FOR CENTRAL AND WESTERN ZONES...WHERE A
COUPLE INCHES OF SNOW HAS FALLEN ALREADY TODAY. THE MORE DYNAMIC
AND MOISTURE RICH PORTION OF THE STORM WILL MOVE INTO THE AREA
THIS EVENING AND CONTINUE OVERNIGHT TONIGHT. THE DYNAMIC WAVE THAT
WILL LEAD TO THIS ENHANCED SNOWFALL OVERNIGHT IS CURRENTLY SEEN ON
WV IMAGERY OVER SOUTHERN BRITISH COLUMBIA. THE MOISTURE RICH
PACIFIC AIR AHEAD OF THE WAVE CAN NOW BE SEEN ON WV IMAGERY
OVER IDAHO AND JUST STARTING TO PUSH INTO FAR WESTERN MONTANA.
SNOW RATES WILL INCREASE AS THIS MOISTURE AND ENHANCED SYNOPTIC
LIFT SLIDE INTO THE AREA LATE THIS AFTERNOON / EARLY THIS EVENING.
OVERNIGHT...THE WAVE WILL SLIDE SOUTH AND EAST TOWARD THE FORECAST
AREA...PRODUCING STRONG QG FORCING OVER THE AREA THROUGH MONDAY
MORNING. BY LATE MONDAY MORNING / EARLY MONDAY AFTERNOON...THE
WAVE WILL PUSH EAST INTO THE DAKOTAS AND SNOW RATES WILL BECOME
SIMILAR TO THOSE WE HAVE SEEN TODAY AS THE ONLY REMAINING FORCING
MECHANISM WILL BE THE ISENTROPIC ASSENT OVER THE COLD AIR.
SINCE THE FORECAST IS PLAYING OUT AS EXPECTED SO FAR AND MODELS
REMAIN CONSISTENT WITH QPF AMOUNTS...HAVE NOT MADE ANY SIGNIFICANT
ADJUSTMENTS TO QPF / SNOW AMOUNTS WITH THIS FORECAST UPDATE.
TEMPERATURES WILL REMAIN FAIRLY STEADY THROUGH THE AFTERNOON TODAY
AND DROP SLIGHTLY FOR THE DAY TOMORROW AS SLIGHTLY COLDER 850 MB
TEMPERATURES SLIDE INTO THE AREA BEHIND THE PASSING WAVE. THUS
HIGH TEMPERATURES IN THE SINGLE DIGITS TO AROUND TEN ARE EXPECTED
TOMORROW. LOWS OVERNIGHT TONIGHT WONT DROP SIGNIFICANTLY AS CLOUD
COVER WITH THE CONTINUOUS PRECIPITATION WILL PREVENT ANY
RADIATIONAL COOLING.
THE SECONDARY WAVE THAT MOVES INTO THE AREA MONDAY NIGHT / TUESDAY
MORNING REMAINS ON TRACK. HOWEVER...MODELS ARE HINTING AT SLIGHTLY
BETTER MOISTURE AVAILABILITY ALONG THE FOOTHILLS AND MOUNTAINS
THAN PREVIOUSLY EXPECTED. THUS HAVE FURTHER INCREASED
POPS...MAINLY SOUTH OF BILLINGS ALONG THE FOOTHILLS. HAVE ALSO
INCREASE SNOW AMOUNTS TO SHOW A FEW ADDITIONAL INCHES OF
ACCUMULATION POSSIBLE THROUGH EARLY TUESDAY MORNING. ONCE THE
SHORTWAVE RAPIDLY DEPARTS THE AREA TUESDAY AFTERNOON...THE AREA
WILL FINALLY DRY OUT AND ALL PRECIPITATION CHANCES WILL END. THE
OTHER EFFECT THE SHORTWAVE WILL HAVE IS TO BRING A REINFORCING
SHOT OF COLD AIR INTO THE AREA THROUGH THE DAY TUESDAY...WHICH
WILL KEEP OUT HIGH TEMPERATURES FROM GETTING OUT THE TEENS IN
MOST LOCATIONS. ALSO FOR LOCATIONS TOWARD MILES CITY AND
BAKER...CLOUD COVER WILL ALREADY BE DECREASING BY TUESDAY
MORNING...THUS TUESDAY MORNING COULD SEE THE COLDEST OVERNIGHT LOW
TEMPERATURES.
CHURCH
.LONG TERM...VALID FOR WED...THU...FRI...SAT...SUN...
MAIN MESSAGE FOR THE EXTENDED FORECAST IS STILL FOCUSED ON THE
HUDSON BAY LOW AND A RIDGE OF HIGH PRESSURE ANCHORED ALONG THE
WEST COAST THROUGH THE ENTIRE WEEK. THIS PATTERN WILL ALLOW ARCTIC
AIR TO PUSH SOUTH OUT OF CANADA ALONG WITH SHORT WAVE ENERGY TO
MOVE ACROSS OUR AREA WITH NORTHERLY FLOW ALOFT. THE ONLY BREAK IN
THE COLD WEATHER WILL BE ON WEDNESDAY AS BOTH GFS AND ECMWF BRING
850 MB TEMPERATURES OF 0C TO +2C INTO THE AREA. GUIDANCE IS GOING
WITH UPPER 30S TO LOWER 40S ON WEDNESDAY BUT BELIEVE SNOW COVER
WILL BE SUFFICIENT ENOUGH TO LIMIT MUCH HEATING AND HAVE CONTINUED
HIGH TEMPERATURES IN THE LOWER 30S.
HAVE GONE MAINLY WITH THE ECMWF MODEL FOR THURSDAY AS IT PUSHES
AN ARCTIC COLD FRONT THROUGH OUR AREA DURING THE MORNING HOURS.
GFS IS ABOUT 6 HOURS BEHIND THE EC AND GIVEN THE DEPTH OF THE COLD
AIR...BELIEVE EC HAS A BETTER HANDLE ON THE TIMING OF THE FRONT.
ANOTHER SURGE OF ARCTIC AIR WILL MOVE INTO THE AREA OVER THE
WEEKEND WHICH WILL KEEP OUR TEMPERATURES WELL BELOW NORMAL FOR
THIS TIME OF THE YEAR. STRONG BAROCLINIC ZONE/FRONTOGENESIS AND
UPSLOPE FLOW DEVELOPING WITH EACH SURGE OF ARCTIC AIR AND THIS
FORCING WILL PRODUCE PERIODS OF SNOW. THE BEST AREAS OF
ACCUMULATING SNOWFALL WILL BE OVER OUR WESTERN AND CENTRAL ZONES.
AFTERNOON TEMPERATURES FRIDAY AND SATURDAY WILL ONLY BE IN THE
TEENS WEST TO SINGLE DIGITS EAST. SATURDAY NIGHT LOOKS TO BE THE
COLDEST WITH READINGS AT ALL LOCATIONS BELOW ZERO. RICHMOND
&&
.AVIATION...
IFR TO VLIFR WILL BE WIDESPREAD TONIGHT THROUGH MONDAY AS HEAVY
SNOWFALL IS EXPECTED AT ALL FLIGHT TERMINALS. HEAVY SNOW WILL
BRING MOUNTAIN OBSCURATIONS. THE SNOW WILL BEGIN TO TAPER OFF BY
MONDAY AFTERNOON. RICHMOND
&&
.PRELIMINARY POINT TEMP/POPS...
MON TUE WED THU FRI SAT SUN
-----------------------------------------------------------
BIL 002/009 905/014 003/032 015/022 009/013 903/007 906/011
+9/S 62/S 00/U 26/S 64/S 44/S 43/S
LVM 002/011 902/020 005/037 017/034 013/018 003/012 903/017
++/S 85/S 00/U 26/S 64/S 45/S 44/S
HDN 003/008 906/013 903/032 009/021 007/012 906/008 909/013
+9/S 62/S 00/U 16/S 64/S 44/S 43/S
MLS 901/006 906/009 902/027 004/017 002/008 909/003 910/007
+8/S 10/B 00/U 12/S 23/S 34/S 43/S
4BQ 003/008 905/010 902/032 007/022 005/011 905/007 907/011
+9/S 21/B 00/U 12/S 23/S 34/S 43/S
BHK 906/001 910/005 905/026 902/016 902/006 913/003 913/008
+9/S 10/B 00/U 01/B 12/S 33/S 43/S
SHR 006/010 906/015 001/034 014/029 010/015 000/014 903/020
++/S 75/S 00/U 13/S 43/S 34/S 43/S
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...WINTER STORM WARNING IN EFFECT UNTIL 6 AM MST TUESDAY FOR
ZONES 28>31-34>36-38>42-56>58-63>68.
WINTER WEATHER ADVISORY IN EFFECT UNTIL 6 AM MST TUESDAY FOR
ZONES 32-33-37.
WY...WINTER STORM WARNING IN EFFECT UNTIL 6 AM MST TUESDAY FOR
ZONES 98-99.
&&
$$
WEATHER.GOV/BILLINGS
Area Forecast Discussion...UPDATED
National Weather Service Missoula MT
1115 AM MST Sun Feb 23 2014
.UPDATE...Allowed the winter weather advisory for Lemhi County to expire.
&&
.DISCUSSION...Web cams across Lemhi County have shown improvement
this morning with some blue skies down by Gimore Summit. There
will continue to be some light snow there in the next 24 hours,
but light accumulations are expected.
Water vapor imagery is indicating that Pacific moisture is pushing
in over Washington and Oregon State. This is an encouraging sign
for the arrival of the precipitation by this afternoon. Also the
trend of the last several runs of the high resolution HRRR model
is showing an increase in coverage of snow across Clearwater
County and northeastern Idaho County, and west-central Montana by mid-
afternoon. This matches the moderately strong warming aloft, the
aforementioned moisture influx and strengthening of the upper
level jet to provide ample lift. This is giving us good confidence
for snowfall rates to increase, potentially to 1+ inch per hour at
times in all the areas that have a winter storm warning out.
There is also indication that there will be a 2nd push of arctic
air late this evening which would strengthen the gap winds through
places like Helmville, Highway 200, I-90, Hellgate Canyon which
would create white-out and very difficult driving conditions at
times.
&&
.AVIATION...A significant winter storm will be moving in today
causing widespread mountain obscuration, low ceilings/visibility
across north central Idaho and western Montana. The light snow
this morning is expected to slowly increase in intensity by mid
morning. For this afternoon, the snow could become quite heavy at
times especially at KMSO and KBTM with the heaviest snow expected
between 23/2000z and 24/0600z. KSMN is expected to see mainly
light snow with short periods of moderate snow during the morning
hours. The light to moderate snow will be tapering off in the
afternoon. KGPI will see light snow showers develop around
23/1500z which will combine with gusty northeast winds to cause
mainly impacts to visibility. Gusty northeast to east winds are
expected to develop across most of western Montana by this
afternoon further impacting visibility.
&&
.PREV DISCUSSION... /ISSUED 443 AM MST Sun Feb 23 2014/
..HEAVY SNOW...HAZARDOUS TRAVEL CONDITIONS TODAY THROUGH MONDAY...
DISCUSSION...
The first part of a significant winter storm has arrived over the
Northern Rockies this morning. Light snow will be present through
much of this morning, with minor accumulations throughout the
region. Be aware, this snow event will only be getting warmed up
this morning. Area roads will begin to deteriorate, with snow and
ice cover creating hazardous travel conditions. However, travel
conditions will only get worse through the day.
THE MAIN SNOW EVENT...
Beginning this afternoon, snow rates across west central Montana
and north central Idaho will quickly increase. Snowfall rates of 1
to 2 inches per hour will be common at both low and high
elevations. The epicenter of the heavy snow remains the Interstate
90 corridor through much of western Montana and Highway 93
northward and southward from Missoula. Snowfall will eventually
become unmanageable by road crews this afternoon, with possible
crippling winter travel conditions developing. Periods of heavy
snow, blowing snow (winds gusting to 40 mph in open areas and
within east-west canyons), low visibility, slick roads, disabled vehicles
in deep snow, and very cold windchill (negative 10 to negative 20
degrees) will all be present, increasing local travel misery. If
you must travel late this afternoon through midday Monday,
consider traveling with items necessary for winter survival in the
event of becoming stuck in the snow.
Snow will slowly diminish throughout Monday, leaving a cold
airmass along the Continental Divide and across northwest Montana.
Travel will likely remain challenging through Monday as well, as
road crews continue to work on clearing travel routes.
Tuesday through Thursday... Residual moisture will be lingering
around western Montana and north central Idaho and will slowly
start to dry out late Tuesday as the high pressure builds in from
the west. Clear skies, light winds and fresh snowfall will help
the temperatures plummet Tue night setting up a very cold
Wednesday morning. By Thursday, another pacific system will be
moving bringing another round of precipitation.
Long range models continue to hint at another arctic push by the
end of this week. This arctic push could potentially be stronger
than the current one so stay tuned!
&&
.MSO WATCHES/WARNINGS/ADVISORIES...
MT...WINTER STORM WARNING until 11 AM MST Monday Butte/Blackfoot
Region...Potomac/Seeley Lake Region.
WINTER STORM WARNING until 11 AM MST Monday Bitterroot/Sapphire
Mountains...Lower Clark Fork Region.
WINTER STORM WARNING until 11 AM MST Monday Missoula/Bitterroot
Valleys.
WINTER STORM WARNING until 11 AM MST Monday Flathead/Mission
Valleys.
WINTER WEATHER ADVISORY until 5 AM MST Monday Kootenai/Cabinet
Region...West Glacier Region.
ID...WINTER STORM WARNING until 10 AM PST Monday Northern Clearwater
Mountains...Southern Clearwater Mountains.
WINTER WEATHER ADVISORY until 10 AM PST Monday Lower Hells
Canyon/Salmon River Region...Orofino/Grangeville Region.
&&
$$
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AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1153 AM CST SUN FEB 23 2014
.UPDATE...
ISSUED AT 625 AM CST SUN FEB 23 2014
JUST GOT A REPORT OF 6 INCHES SNOWFALL IN OGALLALA. ADDITIONAL
SNOWFALL THIS MORNING WOULD LIKELY PUT THAT COUNTY IN THE 6 INCHES
IN 12 HOUR CRITERIA. AN ADDITIONAL 2 INCHES WOULD PUT THEM IN THE
8 INCHES IN 24 HOUR CRITERIA. A WARNING HAS BEEN ISSUED FOR THAT
COUNTY.
UPDATE ISSUED AT 538 AM CST SUN FEB 23 2014
THE METAR AT KOGA IS SHOWING 1 MILE VSBY WITH MODERATE SNOW. THE
NEDOR CAMS IN DEUEL COUNTY SHOW SIGNIFICANT ON THE GROUND AND
STILL FALLING AS THE SECOND DISTURBANCE OPERATES ON THE CHEYENNE
DIVIDE THIS MORNING. GIVEN THE 8 PM 5 INCH SNOWFALL REPORT FROM
THE COOP OBSERVER AT BIG SPRINGS...WINTER STORM CONDITIONS ARE
LIKELY UNDERWAY IN DEUEL COUNTY. SO A WINTER STORM WARNING HAS
BEEN ISSUED FOR THAT COUNTY.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 353 AM CST SUN FEB 23 2014
ROAD SURFACES IN MANY AREAS CROSSED THE FREEZING MARK OVERNIGHT
AND THE SNOW MELTED AN REFROZE PRODUCING HAZARDOUS TRAVEL SO THE
WINTER WEATHER ADVISORY CONTINUES THIS MORNING.
AS ADVERTISED BY THE HIGH RESOLUTION MODELS...THE NAM...ARF...NMM
AND SREF...A COUPLED JET DEVELOPED ACROSS THE FORECAST AREA. THE
HEAVY SNOW WAS LOCALIZED ACROSS CHASE AND HAYES COUNTIES AND
PERHAPS A FEW OTHER AREAS. THE MODELS IN GENERAL SHOWED FAIR
SKILL FORECASTING THIS BUT NEAR ZERO SKILL IN LOCATION. 50 MILES
OF FORECAST ERROR WITH THE LOCATION. THE NAM BOUNCED AROUND
FAVORING CNTL LINCOLN COUNTY...THEN SRN LINCOLN COUNTY AND THEN
KEITH COUNTY. MODEL SKILL IN PREDICTING THE LOCATION OF MESOSCALE
HEAVY SNOW BANDS WAS POOR. THE WINTER STORM WARNING FOR CHASE AND
HAYES COUNTIES CONTINUES THIS MORNING. THE RADAR OUT OF KGLD
CONTINUES TO SHOW LIGHT TO MODERATE SNOW AS THIS FORMERLY HEAVY
BAND OF SNOW IS WEAKENING.
THE LATEST RADAR OUT OF KCYS IN CONJUNCTION WITH THE RAP AND NAM
MODELS SUGGESTS A SECOND BAND OF LIGHT TO MODERATE SNOW WILL MOVE
INTO WRN NEBRASKA THIS MORNING AND THEN LIFT SLOWLY NORTH AS A
DEVELOPING WARM FRONT THIS AFTERNOON AND TONIGHT. BARRING THE
DEVELOPMENT OF AN ORGANIZED HEAVY SNOW BAND...IT IS BELIEVED
SNOWFALL AMOUNTS TODAY WILL BE AN INCH OR LESS USING A 13 TO 1
RATIO WHICH HAS BEEN THE PREVAILING MARKER OUTSIDE OF THE HEAVY
SNOW BAND WHICH DEVELOPED ACROSS FAR SOUTHERN NEBRASKA LAST NIGHT.
THUS FAR...KLBF MEASURED 0.19 INCHES OF LIQUID WITH ABOUT 2
INCHES OF SNOWFALL. AN ADDITIONAL 0.08 IS FORECAST TODAY FOR A
TOTAL OF 0.27 INCHES. YESTERDAYS MODEL MEDIAN QPF WHICH WAS USED
FOR THE FORECAST WAS 0.28. THUS THE ACCURACY OF THE SNOWFALL
FORECAST HINGES ON THE SNOW TO WATER RATIO WHICH IS HIGHLY
DEPENDENT ON DEEP LIFT TO PRODUCE HIGH RATIOS.
THE COBB METHODOLOGY CONTINUES TO ADVERTISE VERY HIGH RATIOS OF
17 TO 20 TO 1 TODAY AND TONIGHT. THESE RATIOS ARE SUSPECT AND
LIKELY BIASED TOWARD THE DEVELOPMENT OF DEEP VERTICAL LIFT SO 13
TO 1 WAS USED TODAY. THE HIGH COBB RATIOS WERE USED
TONIGHT...NEAR 20 TO 1 AT KVTN...BUT HPC HAS OUTLOOKED THIS AREA
FOR SLIGHT RISK OF 4 INCHES OF ACCUMULATION. THE MEDIAN QPF AT
KVTN IS ABOUT 0.15 INCHES AND THE FORECAST IS FOR 0.15. THE 20 TO
1 RATIO THEN PRODUCES 3 INCHES OF SNOW FOR VALENTINE.
THE NAM SUGGESTS GENERALLY MODERATE LIFT AND MID LEVEL
FRONTOGENESIS TONIGHT ACROSS THE NORTH...NO WHERE NEAR THE
STRENGTH EXHIBITED BY THE COUPLED JET STRUCTURE SATURDAY NIGHT
ACROSS THE SOUTH BUT THERE IS POTENTIAL FOR A PERIOD OF MODERATE
SNOW AS THERE IS BANDING POTENTIAL. GIVEN THE UNCERTAINTIES OF
FCSTING BANDED SNOW...A MIDDLE OF THE ROAD FORECAST IS IN PLACE
FOR THE NORTH TONIGHT.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 353 AM CST SUN FEB 23 2014
MONDAY MORNING WILL CONTINUE TO SEE SNOW ACROSS THE NORTHERN PART
OF THE CWA AS THE NEXT WAVE CONTINUES TO PUSH ACROSS S DAKOTA AND
NORTHEAST NEB. MODELS ARE IN FAIR AGREEMENT WITH THE BAND OF SNOW
TO LINGER THROUGH MONDAY MORNING THEN DIMINISHES FOR THE
AFTERNOON. HIGHEST AMOUNTS OF ADDITIONAL SNOW LIKELY AROUND AN
INCH IN THE MORNING BEFORE BECOMING LIGHT AND PUSHING EAST.
HOWEVER YET ANOTHER DISTURBANCE IS FORECAST TO TRACK ACROSS THE
HIGH PLAINS FOR LATE MONDAY INTO TUESDAY. COLD ARCTIC HIGH
PRESSURE WILL BEGIN TO PUSH ACROSS SOUTHERN CANADA BY MONDAY
EVENING. THIS WILL BRING IN SOME DRIER AIR ACROSS THE NORTHERN
PLAINS WITH THE MAIN SNOW BANDING EXPECTED ACROSS THE SOUTHWESTERN
PART OF THE CWA. DEPTH OF THE DENDRITIC GROWTH ZONE IS FAIRLY
DEEP...HOWEVER THE BEST OMEGA IS ACROSS THE HIGHER TERRAIN TO THE
WEST. WILL HAVE TO OVER COME A SOMEWHAT DRY LOWER LEVEL WITH TOP
DOWN SATURATION...ALTHOUGH SHOULD RESULT IN AROUND AN INCH OR TWO
OF SNOW. IF A BAND OF SNOW BECOMES MORE STATIONARY...WHICH IS NOT
SUGGESTED AT THIS TIME BY THE MODELS...BUT AFTER SEE LAST NIGHTS
BAND CAN NOT BE RULED OUT...ANOTHER ADVISORY FOR 2 TO 4 INCHES
WOULD BE WARRANTED.
THE COLD HIGH PRESSURE WILL BEGIN TO BE NOTICES WITH TEMPS
FALLING TO NEAR ZERO FOR TUESDAY MORNING. TUESDAY AFTERNOON AS
THE SNOW DIMINISHES FROM THE NORTH...CLOUDS WILL BE ON THE
DECREASE. COLD ARCTIC AIR WILL SPREAD ACROSS THE AREA WITH HIGHS
STRUGGLING INTO THE 20S. BY TUESDAY NIGHT THE DISTURBANCE WILL BE
SE AND CLEARING SKIES ASSOCIATED WITH THE SFC HIGH WILL COMBINE
WITH THE SNOW PACK TO PRODUCE A VERY COLD LATE FEBRUARY NIGHT.
WIDESPREAD SINGLE DIGITS...AND MOST NOT TO FAR FROM ZERO. LOCALLY
BELOW ZERO STILL POSSIBLE...HOWEVER CENTER OF THE HIGH IS OVER
HEAD CLOSER TO MIDNIGHT SO TEMPS MIGHT BEGIN TO CLIMB OR AT LEAST
HOLD STEADY FOR THE EARLY MORNING HOURS.
SW WINDS DEVELOP FOR WED...ON THE BACK SIDE OF THE HIGH...WITH
WARMER AIR TO PUSH ACROSS THE AREA. HIGHS WARM INTO THE
30S...HOWEVER SNOW PACK COULD PLAY A ROLL IN TEMPS BELOW GUIDANCE.
REST OF THE WORK WEEK WILL CONTINUES TO SEE A RIDGE ACROSS THE
SOUTHERN ROCKIES WHICH TRAILS TO THE NW INTO THE PAC NORTHWEST.
THIS FAVORS A NORTHWEST FLOW AND PROGRESSIVE CLIPPER SYSTEM AND ON
AND OFF CLOUDS AND MAYBE SOME LIGHT SNOW. BY THE WEEKEND BOTH THE
GFS AND THE EC ARE CARVING A TROUGH ACROSS THE WESTERN CONUS WITH
MORE ZONAL FLOW EAST OF THE ROCKIES. WILL CONTINUE TO MONITOR THIS
SYSTEM WHICH MODELS EJECT ONTO THE PLAINS LATE SATURDAY INTO
SUNDAY. STILL A WEEK OUT BUT SOMETHING TO MONITOR.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1147 AM CST SUN FEB 23 2014
MOSTLY MVFR CONDITIONS/CEILINGS ARE EXPECTED THROUGH THIS TAF
PERIOD. SOME DRYING OF THE ATMOSPHERE MAY ALLOW FOR VFR ACROSS
NORTH CENTRAL NEBRASKA THIS AFTERNOON. ANOTHER DISTURBANCE WILL
DROP SOUTHEAST TONIGHT WITH SNOW REDEVELOPING ACROSS WESTERN
NEBRASKA THIS EVENING...AND THEN SPREADING EAST INTO NORTH CENTRAL
AND CENTRAL NEBRASKA LATER TONIGHT INTO MONDAY. WINDS THROUGH THE
PERIOD WILL REMAIN LIGHT.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL NOON CST /11 AM MST/ TODAY FOR
NEZ022>025-035>038-058-059.
WINTER STORM WARNING UNTIL 11 AM MST THIS MORNING FOR NEZ056-057.
&&
$$
UPDATE...CDC
SHORT TERM...CDC
LONG TERM...MASEK
AVIATION...TAYLOR
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
521 PM EST SUN FEB 23 2014
.SYNOPSIS...
FAST WESTERLY FLOW ALOFT WILL CONTAIN SEVERAL WEAK...AN GENERALLY
MOISTURE STARVED UPPER AIR DISTURBANCES WHICH WILL CROSS THE
REGION THROUGH TUESDAY. A STRONGER DISTURBANCE DIVING SOUTHEAST FROM
THE UPPER MIDWEST WILL INTERACT WITH A STALLED-OUT FRONT ACROSS THE
SOUTHEASTERN U.S. AND HELP TO SPIN-UP AN AREA OF LOW PRESSURE ALONG
THE OUTER BANKS OF NORTH CAROLINA. A LIGHT...ACCUMULATING SNOW IS
POSSIBLE LATE TUESDAY NIGHT AND WEDNESDAY. A BLAST OF ARCTIC AIR
WILL FOLLOW FOR LATE IN THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
SEVERAL STRIPES OF MAINLY MID AND HIGH CLOUDS WERE PRESENT ACROSS
THE FCST AREA THIS AFTERNOON...WITH NO PRECIP NOTED OVER THE PAST
SEVERAL HOURS...AND NONE EXPECTED FOR THE NEXT 1-2 HRS.
A THICKENING...AND MORE EXTENSIVE CLOUD SHIELD /ASSOCIATED WITH THE
PASSAGE OF THE LEFT EXIT REGION OF A 130 KT JET OVER A QUASI STNRY
850 MB FRONTAL BOUNDARY/ WILL QUICKLY OVERSPREAD THE CENTRAL AND
WESTERN MTNS LATE THIS AFTERNOON...REACHING THE LOWER SUSQ VALLEY
AROUND OR SHORTLY BEFORE DUSK.
SHORT TERM...HIGH RES MODELS SHOW A RANGE OF SOLUTIONS WITH RESPECT
TO THE AMOUNT AND AREAL COVERAGE OF LIGHT MIXED PRECIP /THEN SNOW/
LATE TODAY THROUGH EARLY TONIGHT ACROSS MAINLY THE SOUTHERN HALF OF
PENN.
15Z-17Z HRRR HAS BEEN THE MOST AGGRESSIVE OF ALL OPERATIONAL MODELS
/AND NEAR THE HIGH END OF THE SREF PLUMES/ BRINGING A GENERAL 1-3
TENTHS OF LEQ PRECIP TO THE SOUTHERN THIRD TO HALF OF THE STATE LATE
TODAY THROUGH ABOUT MIDNIGHT...WHILE THE LATEST HIGH-RES WRF ARW
AND OPERATIONAL NAM PAINTS VERY LITTLE OR NO QPF TO THE EAST OF THE
LAURELS.
SREF DISPLAYS A GOOD COMPROMISE AT THIS POINT...INDICATING A FEW TO
SEVERAL HUNDREDTHS OF QPF ACROSS MUCH OF CENTRAL AND SERN PA...WITH
OVER A TENTH OF AN INCH ACROSS THE LAURELS.
THE P-TYPE THROUGH 00Z WILL BE EITHER PLAIN RAIN /SE ZONES/ OR A
LIGHT RAIN AND LIGHT SNOW MIX IN THE CENTRAL MTS /WHERE 925 MB WET
BULB TEMPS WILL RIGHT AROUND 0C/...BUT MAINLY SNOW IN THE HIGHER
ELEVATIONS.
ALL OF THIS TRANSLATES INTO THE LIKELIHOOD OF AN INCH OR TWO OF SNOW
ACROSS CAMBRIA AND SOMERSET COUNTY TONIGHT /LOCALLY 3 INCHES
POSSIBLE ON THE RIDGES WETS OF RT 219/...WHILE THE CENTRAL AND
SOUTHERN VALLEYS SEE A DUSTING TO PERHAPS A LITTLE OVER ONE HALF OF
AN INCH. EXPECT LITTLE OR NO SNOW TO THE NORTH OF INTERSTATE 80 LATE
TODAY AND TONIGHT. IT/S OFTEN A TRICKY CALL TRYING TO FORECAST THESE
WEAKLY FORCED...MOISTURE STARVED MESOSCALE EVENTS.
VERY LATE TONIGHT...ANY LINGERING PRECIP WILL BE IN THE FORM OF SNOW
SHOWERS AND CONFINED TO THE LAURELS.
TEMPS FOR THE REST OF THIS AFTN WILL BE IN THE 40S TO NEAR 50F IN
THE SOUTHEAST...BUT THE THICKENING CLOUDS WILL HOLD THE MAXES UNDER
40F OVER THE WRN MTNS. THIS WILL BE THE START OF THE DOWNTURN TO OUR
TEMPS.
COLDER AIR WILL BE ADVECTING INTO THE NW. LAKE ERIE IS PRETTY MUCH
FROZEN...SO MOISTURE FLUX WILL BE LOW. HOWEVER...THE MOISTURE FROM
THE OTHER LAKES UNDER THE CYCLONIC FLOW ALOFT WILL BE ABLE TO
GENERATE PLENTY OF CLOUDS AND A FEW SHSN WITH LOCALIZED LIGHT ACCUMS
OF AN INCH OR LESS. MINS TONIGHT /RANGING FROM 10-15F ACROSS THE
MTNS...AND LOWER TO MID 20S IN THE SE/ WILL BE NEAR NORMAL IN THE
SOUTH BUT ABOUT 5F BELOW NORMAL IN THE NRN MTS.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/...
A RELATIVELY FLAT SHORTWAVE AND ASSOCIATED 850-700 MB THERMAL TROUGH
SLIDES EAST ACROSS THE CWA MONDAY. THERE WILL BE PLENTY OF CLOUDS
ACROSS THE NORTH AND WEST. LAKE EFFECT...AND OROGRAPHIC STRATUS AND
STRATO CU CLOUD LAYER TEMPS WILL BE SMACK IN THE MIDDLE OF THE
FAVORABLE THERMAL RIBBON FOR DENDRITIC GROWTH...SO EXPECT TO SEE
OCCASIONAL FLURRIES AND SCTD MTN SNOW SHOWERS WITH AREAS OF LIGHT
ACCUMS...MAINLY ON THE RIDGES OF THE LAURELS...AND NW MTNS TO THE
WEST OF ROUTE 219.
PERHAPS THE MOST NOTICEABLE WEATHER ELEMENT MONDAY WILL BE THE GUSTY
WNW WIND. SUSTAINED SPEEDS OF 15 TO 20 MPH AND GUSTS INTO THE L30S
ARE LIKELY. MAX TEMPS WILL VARY FROM THE UPPER TEENS TO AROUND 20F
IN THE NW. THE SE WILL HAVE SOME DOWNSLOPE AND LIKELY PLENTY OF
SUNSHINE /75-90 PERCENT SUN/ BUT A -14C 8H TEMP WILL MEAN THAT IT
WILL STRUGGLE TO GET INTO THE M30S.
WIND CHILLS WILL RANGE FROM ZERO TO 5 ABOVE AT TIMES ACROSS THE NW
MTNS AND LAURELS...TO AROUND 20F IN THE LOWER SUSQ VALLEY.
&&
.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
THE WORK WEEK WILL SEE THE RETURN OF COLDER AIR AND STRONG
NORTHWESTERLY FLOW. TEMPERATURES WILL GET SUCCESSIVELY COLDER AS
THE WEEK PROGRESSES. A RIDGE WILL RE- ESTABLISH ITSELF OVER THE
FAR WESTERN UNITED STATES...WHICH SHOULD ALLOW COLDER AIR TO PUSH
SOUTHWARD INTO THE GREAT LAKES AND NORTHEASTERN UNITED STATES.
A WEAK CLIPPER SHOULD GLANCE THE NORTHERN HALF OF PA MONDAY NIGHT
INTO TUESDAY. THIS SHOULD BRING SOME LIGHT SNOW TO THE NW
MTNS...AND FURTHER DECREASE TEMPERATURES.
A WEAK SHORT WAVE WILL FOLLOW IN ITS WAKE...WHICH SHOULD BRING
ANOTHER CHANCE FOR SNOW TO THE CENTRAL AND NW MTNS.
THE NEXT CHANCE FOR MORE WIDESPREAD SNOW WILL BE WEDNESDAY...AS A
DEEPENING TROUGH WILL SWING THROUGH THE MIDWEST. MOST OF THE
MOISTURE WILL REMAIN OFF THE COAST. HOWEVER...GIVEN THE COLD AIR
MASS...COUPLED WITH THE MOIST SOUTHWESTERLY FLOW COULD ALLOW FOR ANOTHER
ROUND OF SNOW ACROSS PENNSYLVANIA WEDNESDAY. THERE IS STILL SOME
VARIANCES ON SNOW AMOUNT AND POSITION SO HAVE LEFT BROAD POPS
WEDNESDAY. THIS SYSTEM SHOULD QUICKLY EXIT THE REGION WEDNESDAY
EVENING. HAVE KEPT POPS MAINLY IN THE 30-40 PERCENT RANGE THROUGH
MUCH OF THIS PERIOD...THOUGH HAVE INCREASED IT THROUGHOUT THE
LAURELS AND THE NW MTNS...DUE TO THE UPSLOPE FLOW ENHANCEMENT.
THE LONG RANGE MODELS ARE SHOWING A BRIEF WARMUP AT THE END OF THE
WORK WEEK. HOWEVER TEMPERATURES SHOULD REMAIN BELOW
FREEZING...AND WILL DROP BACK DOWN NEXT WEEKEND.
&&
.AVIATION /22Z SUNDAY THROUGH FRIDAY/...
BAND OF LGT RAIN/SNOW SHOWERS WILL STREAK ACRS THE SRN AIRFIELDS
THRU 03-06Z...ACCOMPANIED MVFR TO LOW END VFR CONDS TO THE E OF
THE MTNS. ELEVATION FACTOR AT JST RESULTING IN LOWER CONDS WITH IFR
TO EVEN LIFR FOR A BRIEF TIME THIS EVE. KEPT MDT/LNS JUST ABOVE
MVFR ALTHOUGH A PERIOD OF MVFR IS PSBL AFT 00Z. HIRES ENSEMBLE
MEAN SHIFTS ALL PCPN E OF THE AIRSPACE BY 09Z. TO THE NORTH...
EXPECT VFR BKN CIGS 050-100 TO PREVAIL INTO TNGT. A MORE TYPICAL
POST-FRONTAL NW FLOW PATTERN WILL DEVELOP INTO MONDAY WITH GUSTY
WNW WINDS AND -SHSN INVOF BFD BY MORNING.
SEVERAL WEAK DISTURBANCES ALOFT WILL ROTATE THROUGH THE REGION
INTO EARLY NEXT WEEK...AS A BROAD AND INCREASINGLY COLD CYCLONIC
FLOW PATTERN GRIPS MUCH OF THE NERN U.S. COASTAL LOW PRES WILL
DEVELOP NEAR OBX AND LIFT NEWD ON WED. A MAINLY DRY COLD FROPA
WILL REINFORCE THE COLD AIRMASS ON THURS. A GULF COAST SYSTEM MAY
AFFECT THE AREA BY NEXT FRI/SAT.
OUTLOOK...
MON...MVFR/SHSN NW. VFR ELSEWHERE.
TUE-WED...MVFR-IFR PSBL WITH -SN.
THURS...MVFR/SNSH NW. VFR ELSEWHERE.
FRI...RESTRICTIONS PSBL INTO FRI NGT.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...DANGELO/LAMBERT
LONG TERM...CERU/EVANEGO
AVIATION...STEINBUGL
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
357 PM EST SUN FEB 23 2014
.SYNOPSIS...
FAST WESTERLY FLOW ALOFT WILL CONTAIN SEVERAL WEAK...AN GENERALLY
MOISTURE STARVED UPPER AIR DISTURBANCES WHICH WILL CROSS THE
REGION THROUGH TUESDAY. A STRONGER DISTURBANCE DIVING SOUTHEAST FROM
THE UPPER MIDWEST WILL INTERACT WITH A STALLED-OUT FRONT ACROSS THE
SOUTHEASTERN U.S. AND HELP TO SPIN-UP AN AREA OF LOW PRESSURE ALONG
THE OUTER BANKS OF NORTH CAROLINA. A LIGHT...ACCUMULATING SNOW IS
POSSIBLE LATE TUESDAY NIGHT AND WEDNESDAY. A BLAST OF ARCTIC AIR
WILL FOLLOW FOR LATE IN THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
SEVERAL STRIPES OF MAINLY MID AND HIGH CLOUDS WERE PRESENT ACROSS
THE FCST AREA THIS AFTERNOON...WITH NO PRECIP NOTED OVER THE PAST
SEVERAL HOURS...AND NONE EXPECTED FOR THE NEXT 1-2 HRS.
A THICKENING...AND MORE EXTENSIVE CLOUD SHIELD /ASSOCIATED WITH THE
PASSAGE OF THE LEFT EXIT REGION OF A 130 KT JET OVER A QUASI STNRY
850 MB FRONTAL BOUNDARY/ WILL QUICKLY OVERSPREAD THE CENTRAL AND
WESTERN MTNS LATE THIS AFTERNOON...REACHING THE LOWER SUSQ VALLEY
AROUND OR SHORTLY BEFORE DUSK.
SHORT TERM...HIGH RES MODELS SHOW A RANGE OF SOLUTIONS WITH RESPECT
TO THE AMOUNT AND AREAL COVERAGE OF LIGHT MIXED PRECIP /THEN SNOW/
LATE TODAY THROUGH EARLY TONIGHT ACROSS MAINLY THE SOUTHERN HALF OF
PENN.
15Z-17Z HRRR HAS BEEN THE MOST AGGRESSIVE OF ALL OPERATIONAL MODELS
/AND NEAR THE HIGH END OF THE SREF PLUMES/ BRINGING A GENERAL 1-3
TENTHS OF LEQ PRECIP TO THE SOUTHERN THIRD TO HALF OF THE STATE LATE
TODAY THROUGH ABOUT MIDNIGHT...WHILE THE LATEST HIGH-RES WRF ARW
AND OPERATIONAL NAM PAINTS VERY LITTLE OR NO QPF TO THE EAST OF THE
LAURELS.
SREF DISPLAYS A GOOD COMPROMISE AT THIS POINT...INDICATING A FEW TO
SEVERAL HUNDREDTHS OF QPF ACROSS MUCH OF CENTRAL AND SERN PA...WITH
OVER A TENTH OF AN INCH ACROSS THE LAURELS.
THE P-TYPE THROUGH 00Z WILL BE EITHER PLAIN RAIN /SE ZONES/ OR A
LIGHT RAIN AND LIGHT SNOW MIX IN THE CENTRAL MTS /WHERE 925 MB WET
BULB TEMPS WILL RIGHT AROUND 0C/...BUT MAINLY SNOW IN THE HIGHER
ELEVATIONS.
ALL OF THIS TRANSLATES INTO THE LIKELIHOOD OF AN INCH OR TWO OF SNOW
ACROSS CAMBRIA AND SOMERSET COUNTY TONIGHT /LOCALLY 3 INCHES
POSSIBLE ON THE RIDGES WETS OF RT 219/...WHILE THE CENTRAL AND
SOUTHERN VALLEYS SEE A DUSTING TO PERHAPS A LITTLE OVER ONE HALF OF
AN INCH. EXPECT LITTLE OR NO SNOW TO THE NORTH OF INTERSTATE 80 LATE
TODAY AND TONIGHT. IT/S OFTEN A TRICKY CALL TRYING TO FORECAST THESE
WEAKLY FORCED...MOISTURE STARVED MESOSCALE EVENTS.
VERY LATE TONIGHT...ANY LINGERING PRECIP WILL BE IN THE FORM OF SNOW
SHOWERS AND CONFINED TO THE LAURELS.
TEMPS FOR THE REST OF THIS AFTN WILL BE IN THE 40S TO NEAR 50F IN
THE SOUTHEAST...BUT THE THICKENING CLOUDS WILL HOLD THE MAXES UNDER
40F OVER THE WRN MTNS. THIS WILL BE THE START OF THE DOWNTURN TO OUR
TEMPS.
COLDER AIR WILL BE ADVECTING INTO THE NW. LAKE ERIE IS PRETTY MUCH
FROZEN...SO MOISTURE FLUX WILL BE LOW. HOWEVER...THE MOISTURE FROM
THE OTHER LAKES UNDER THE CYCLONIC FLOW ALOFT WILL BE ABLE TO
GENERATE PLENTY OF CLOUDS AND A FEW SHSN WITH LOCALIZED LIGHT ACCUMS
OF AN INCH OR LESS. MINS TONIGHT /RANGING FROM 10-15F ACROSS THE
MTNS...AND LOWER TO MID 20S IN THE SE/ WILL BE NEAR NORMAL IN THE
SOUTH BUT ABOUT 5F BELOW NORMAL IN THE NRN MTS.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/...
A RELATIVELY FLAT SHORTWAVE AND ASSOCIATED 850-700 MB THERMAL TROUGH
SLIDES EAST ACROSS THE CWA MONDAY. THERE WILL BE PLENTY OF CLOUDS
ACROSS THE NORTH AND WEST. LAKE EFFECT...AND OROGRAPHIC STRATUS AND
STRATO CU CLOUD LAYER TEMPS WILL BE SMACK IN THE MIDDLE OF THE
FAVORABLE THERMAL RIBBON FOR DENDRITIC GROWTH...SO EXPECT TO SEE
OCCASIONAL FLURRIES AND SCTD MTN SNOW SHOWERS WITH AREAS OF LIGHT
ACCUMS...MAINLY ON THE RIDGES OF THE LAURELS...AND NW MTNS TO THE
WEST OF ROUTE 219.
PERHAPS THE MOST NOTICEABLE WEATHER ELEMENT MONDAY WILL BE THE GUSTY
WNW WIND. SUSTAINED SPEEDS OF 15 TO 20 MPH AND GUSTS INTO THE L30S
ARE LIKELY. MAX TEMPS WILL VARY FROM THE UPPER TEENS TO AROUND 20F
IN THE NW. THE SE WILL HAVE SOME DOWNSLOPE AND LIKELY PLENTY OF
SUNSHINE /75-90 PERCENT SUN/ BUT A -14C 8H TEMP WILL MEAN THAT IT
WILL STRUGGLE TO GET INTO THE M30S.
WIND CHILLS WILL RANGE FROM ZERO TO 5 ABOVE AT TIMES ACROSS THE NW
MTNS AND LAURELS...TO AROUND 20F IN THE LOWER SUSQ VALLEY.
&&
.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
THE WORK WEEK WILL SEE THE RETURN OF COLDER AIR AND STRONG
NORTHWESTERLY FLOW. TEMPERATURES WILL GET SUCCESSIVELY COLDER AS
THE WEEK PROGRESSES. A RIDGE WILL RE- ESTABLISHE ITSELF OVER THE
FAR WESTERN UNITED STATES...WHICH SHOULD ALLOW COLDER AIR TO PUSH
SOUTHWARD INTO THE GREAT LAKES AND NORTHEASTERN UNITED STATES.
A WEAK CLIPPER SHOULD GLANCE THE NORTHERN HALF OF PA MONDAY NIGHT
INTO TUESDAY. THIS SHOULD BRING SOME LIGHT SNOW TO THE NW
MTNS...AND FURTHER DECREASE TEMPERATURES.
A WEAK SHORT WAVE WILL FOLLOW IN ITS WAKE...WHICH SHOULD BRING
ANOTHER CHANCE FOR SNOW TO THE CENTRAL AND NW MTNS.
THE NEXT CHANCE FOR MORE WIDESPREAD SNOW WILL BE WEDNESDAY...AS A
DEEPENING TROUGH WILL SWING THROUGH THE MIDWEST. MOST OF THE
MOISTURE WILL REMAIN OFF THE COAST. HOWEVER...GIVEN THE COLD AIR
MASS...COUPLED WITH THE MOIST SOUTHWESTERLY FLOW COULD ALLOW FOR ANOTHER
ROUND OF SNOW ACROSS PENNSYLVANIA WEDNESDAY. THERE IS STILL SOME
VARIANCES ON SNOW AMOUNT AND POSITION SO HAVE LEFT BROAD POPS
WEDNESDAY. THIS SYSTEM SHOULD QUICKLY EXIT THE REGION WEDNESDAY
EVENING. HAVE KEPT POPS MAINLY IN THE 30-40 PERCENT RANGE THROUGH
MUCH OF THIS PERIOD...THOUGH HAVE INCREASED IT THROUGHOUT THE
LAURELS AND THE NW MTNS...DUE TO THE UPSLOPE FLOW ENHANCEMENT.
THE LONG RANGE MODELS ARE SHOWING A BRIEF WARMUP AT THE END OF THE
WORK WEEK. HOWEVER TEMPERATURES SHOULD REMAIN BELOW
FREEZING...AND WILL DROP BACK DOWN NEXT WEEKEND.
&&
.AVIATION /21Z SUNDAY THROUGH FRIDAY/...
SFC COLD FRONT HAS PUSHED TO THE SOUTH OF THE PENN/MD BORDER AT
MIDDAY. INCREASING DEEP LAYER LIFT WILL CAUSE CLOUDS TO OVERSPREAD
THE LAUREL HIGHLANDS AND NW MTNS LATE THIS AFTERNOON...AND THE REST
OF THE REGION TONIGHT.
INCREASING...DOWNSLOPE WESTERLY FLOW OF AROUND 10 KTS WILL COMBINE
WITH THE MODERATE TEMPS ALOFT TO PRODUCE BREAKS IN THE LAYERED MID
AND HIGH CLOUDS BUT NOTHING MORE THAN A SPRINKLE OR PASSING FLURRY
THIS AFTERNOON.
PERIODS OF MVFR...AND EVEN SOME BRIEF IFR...WILL DEVELOP IN SNOW
SHOWERS /MAINLY ACROSS THE LAUREL HIGHLANDS LATE TODAY...AND
TONIGHT/. SOMEWHAT LOWER PROBABILITY EXISTS FOR THESE FLIGHT
REDUCTIONS SPREADING INTO THE KMDT AND KLNS AREAS TONIGHT. KEPT
VSBYS JUST A TAD ABOVE MVFR AT KMDT...KLNS AND KTHV AS SOME AREAS
OF LIGHT RAIN/SNOW SPREAD ACROSS THE REGION THIS EVENING UNTIL
AROUND 05Z.
ELSEWHERE...ACROSS MUCH OF CENTRAL AND NRN PENN...GENERALLY VFR BKN
CIGS WILL PREVAIL WITH JUST SOME SPOTTY LIGHT RAIN/SNOW
SHOWERS...CHANGING TO SNOW SHOWERS TONIGHT.
OUTLOOK...
MON...MVFR/SHSN NW. VFR ELSEWHERE.
TUE...MVFR-IFR PSBL IN -SHSN. VFR ELSEWHERE.
WED...PSBL REDUCTIONS DUE TO LOW PRES DEVELOPING OVR NC MOVG
NEWD.
THUR...MVFR/SNSH NW. VFR ELSEWHERE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...DANGELO/LAMBERT
LONG TERM...CERU/EVANEGO
AVIATION...LAMBERT/GARTNER
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
231 PM EST SUN FEB 23 2014
.SYNOPSIS...
FAST WESTERLY FLOW ALOFT WILL CONTAIN SEVERAL WEAK...AN GENERALLY
MOISTURE STARVED UPPER AIR DISTURBANCES WHICH WILL CROSS THE
REGION THROUGH TUESDAY. A STRONGER DISTURBANCE DIVING SOUTHEAST FROM
THE UPPER MIDWEST WILL INTERACT WITH A STALLED-OUT FRONT ACROSS THE
SOUTHEASTERN U.S. AND HELP TO SPIN-UP AN AREA OF LOW PRESSURE ALONG
THE OUTER BANKS OF NORTH CAROLINA. A LIGHT...ACCUMULATING SNOW IS
POSSIBLE LATE TUESDAY NIGHT AND WEDNESDAY. A BLAST OF ARCTIC AIR
WILL FOLLOW FOR LATE IN THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
SEVERAL STRIPES OF MAINLY MID AND HIGH CLOUDS WERE PRESENT ACROSS
THE FCST AREA THIS AFTERNOON...WITH NO PRECIP NOTED OVER THE PAST
SEVERAL HOURS...AND NONE EXPECTED FOR THE NEXT 1-2 HRS.
A THICKENING...AND MORE EXTENSIVE CLOUD SHIELD /ASSOCIATED WITH THE
PASSAGE OF THE LEFT EXIT REGION OF A 130 KT JET OVER A QUASI STNRY
850 MB FRONTAL BOUNDARY/ WILL QUICKLY OVERSPREAD THE CENTRAL AND
WESTERN MTNS LATE THIS AFTERNOON...REACHING THE LOWER SUSQ VALLEY
AROUND OR SHORTLY BEFORE DUSK.
SHORT TERM...HIGH RES MODELS SHOW A RANGE OF SOLUTIONS WITH RESPECT
TO THE AMOUNT AND AREAL COVERAGE OF LIGHT MIXED PRECIP /THEN SNOW/
LATE TODAY THROUGH EARLY TONIGHT ACROSS MAINLY THE SOUTHERN HALF OF
PENN.
15Z-17Z HRRR HAS BEEN THE MOST AGGRESSIVE OF ALL OPERATIONAL MODELS
/AND NEAR THE HIGH END OF THE SREF PLUMES/ BRINGING A GENERAL 1-3
TENTHS OF LEQ PRECIP TO THE SOUTHERN THIRD TO HALF OF THE STATE LATE
TODAY THROUGH ABOUT MIDNIGHT...WHILE THE LATEST HIGH-RES WRF ARW
AND OPERATIONAL NAM PAINTS VERY LITTLE OR NO QPF TO THE EAST OF THE
LAURELS.
SREF DISPLAYS A GOOD COMPROMISE AT THIS POINT...INDICATING A FEW TO
SEVERAL HUNDREDTHS OF QPF ACROSS MUCH OF CENTRAL AND SERN PA...WITH
OVER A TENTH OF AN INCH ACROSS THE LAURELS.
THE P-TYPE THROUGH 00Z WILL BE EITHER PLAIN RAIN /SE ZONES/ OR A
LIGHT RAIN AND LIGHT SNOW MIX IN THE CENTRAL MTS /WHERE 925 MB WET
BULB TEMPS WILL RIGHT AROUND 0C/...BUT MAINLY SNOW IN THE HIGHER
ELEVATIONS.
ALL OF THIS TRANSLATES INTO THE LIKELIHOOD OF AN INCH OR TWO OF SNOW
ACROSS CAMBRIA AND SOMERSET COUNTY TONIGHT /LOCALLY 3 INCHES
POSSIBLE ON THE RIDGES WETS OF RT 219/...WHILE THE CENTRAL AND
SOUTHERN VALLEYS SEE A DUSTING TO PERHAPS A LITTLE OVER ONE HALF OF
AN INCH. EXPECT LITTLE OR NO SNOW TO THE NORTH OF INTERSTATE 80 LATE
TODAY AND TONIGHT. IT/S OFTEN A TRICKY CALL TRYING TO FORECAST THESE
WEAKLY FORCED...MOISTURE STARVED MESOSCALE EVENTS.
VERY LATE TONIGHT...ANY LINGERING PRECIP WILL BE IN THE FORM OF SNOW
SHOWERS AND CONFINED TO THE LAURELS.
TEMPS FOR THE REST OF THIS AFTN WILL BE IN THE 40S TO NEAR 50F IN
THE SOUTHEAST...BUT THE THICKENING CLOUDS WILL HOLD THE MAXES UNDER
40F OVER THE WRN MTNS. THIS WILL BE THE START OF THE DOWNTURN TO OUR
TEMPS.
COLDER AIR WILL BE ADVECTING INTO THE NW. LAKE ERIE IS PRETTY MUCH
FROZEN...SO MOISTURE FLUX WILL BE LOW. HOWEVER...THE MOISTURE FROM
THE OTHER LAKES UNDER THE CYCLONIC FLOW ALOFT WILL BE ABLE TO
GENERATE PLENTY OF CLOUDS AND A FEW SHSN WITH LOCALIZED LIGHT ACCUMS
OF AN INCH OR LESS. MINS TONIGHT /RANGING FROM 10-15F ACROSS THE
MTNS...AND LOWER TO MID 20S IN THE SE/ WILL BE NEAR NORMAL IN THE
SOUTH BUT ABOUT 5F BELOW NORMAL IN THE NRN MTS.
&&
.SHORT TERM /MONDAY/...
A RELATIVELY FLAT SHORTWAVE AND ASSOCIATED 850-700 MB THERMAL TROUGH
SLIDES EAST ACROSS THE CWA MONDAY. THERE WILL BE PLENTY OF CLOUDS
ACROSS THE NORTH AND WEST. LAKE EFFECT...AND OROGRAPHIC STRATUS AND
STRATO CU CLOUD LAYER TEMPS WILL BE SMACK IN THE MIDDLE OF THE
FAVORABLE THERMAL RIBBON FOR DENDRITIC GROWTH...SO EXPECT TO SEE
OCCASIONAL FLURRIES AND SCTD MTN SNOW SHOWERS WITH AREAS OF LIGHT
ACCUMS...MAINLY ON THE RIDGES OF THE LAURELS...AND NW MTNS TO THE
WEST OF ROUTE 219.
PERHAPS THE MOST NOTICEABLE WEATHER ELEMENT MONDAY WILL BE THE GUSTY
WNW WIND. SUSTAINED SPEEDS OF 15 TO 20 MPH AND GUSTS INTO THE L30S
ARE LIKELY. MAX TEMPS WILL VARY FROM THE UPPER TEENS TO AROUND 20F
IN THE NW. THE SE WILL HAVE SOME DOWNSLOPE AND LIKELY PLENTY OF
SUNSHINE /75-90 PERCENT SUN/ BUT A -14C 8H TEMP WILL MEAN THAT IT
WILL STRUGGLE TO GET INTO THE M30S.
WIND CHILLS WILL RANGE FROM ZERO TO 5 ABOVE AT TIMES ACROSS THE NW
MTNS AND LAURELS...TO AROUND 20F IN THE LOWER SUSQ VALLEY.
&&
.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
THE WORK WEEK WILL SEE THE RETURN OF COLDER AIR AND STRONG
NORTHWESTERLY FLOW. TEMPERATURES WILL GET SUCCESSIVELY COLDER AS
THE WEEK PROGRESSES. AS A RIDGE RE- ESTABLISHES ITSELF OVER THE
FAR WESTERN UNITED STATES...ALLOWING COLDER AIR TO PUSH SOUTHWARD
INTO THE GREAT LAKES AND NORTHEASTERN UNITED STATES.
A SECOND SYSTEM COULD SPREAD ANOTHER ROUND OF LIGHT SNOW ACROSS
PENNSYLVANIA EARLY TUESDAY...WITH A POTENTIALLY MORE SIGNIFICANT
SYSTEM POSSIBLY BRINGING ADDITIONAL SNOW TO THE REGION TUES NIGHT
INTO WEDNESDAY. KEPT POPS IN THE 30-40 PERCENT RANGE THROUGH MUCH
OF THIS PERIOD...AS CONFIDENCE IN THE TIMING AND DETAILS OF THESE
SYSTEMS IS LOW AT THIS RANGE.
THE 12Z GEFS SHOWS 850 TEMPS DROPPING TO -2SD FOR THU AND FRI...SO
IT LOOKS LIKE A COLD END TO NEXT WEEK IS IN STORE.
&&
.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
SFC COLD FRONT HAS PUSHED TO THE SOUTH OF THE PENN/MD BORDER AT
MIDDAY. INCREASING DEEP LAYER LIFT WILL CAUSE CLOUDS TO OVERSPREAD
THE LAUREL HIGHLANDS AND NW MTNS LATE THIS AFTERNOON...AND THE REST
OF THE REGION TONIGHT.
INCREASING...DOWNSLOPE WESTERLY FLOW OF AROUND 10 KTS WILL COMBINE
WITH THE MODERATE TEMPS ALOFT TO PRODUCE BREAKS IN THE LAYERED MID
AND HIGH CLOUDS BUT NOTHING MORE THAN A SPRINKLE OR PASSING FLURRY
THIS AFTERNOON.
PERIODS OF MVFR...AND EVEN SOME BRIEF IFR...WILL DEVELOP IN SNOW
SHOWERS /MAINLY ACROSS THE LAUREL HIGHLANDS LATE TODAY...AND
TONIGHT/. SOMEWHAT LOWER PROBABILITY EXISTS FOR THESE FLIGHT
REDUCTIONS SPREADING INTO THE KMDT AND KLNS AREAS TONIGHT. KEPT
VSBYS JUST A TAD ABOVE MVFR AT KMDT...KLNS AND KTHV AS SOME AREAS
OF LIGHT RAIN/SNOW SPREAD ACROSS THE REGION THIS EVENING UNTIL
AROUND 05Z.
ELSEWHERE...ACROSS MUCH OF CENTRAL AND NRN PENN...GENERALLY VFR BKN
CIGS WILL PREVAIL WITH JUST SOME SPOTTY LIGHT RAIN/SNOW
SHOWERS...CHANGING TO SNOW SHOWERS TONIGHT.
OUTLOOK...
MON...MVFR/SHSN NW. VFR ELSEWHERE.
TUE...MVFR-IFR PSBL IN -SHSN. VFR ELSEWHERE.
WED...PSBL REDUCTIONS DUE TO LOW PRES DEVELOPING OVR NC MOVG
NEWD.
THUR...MVFR/SNSH NW. VFR ELSEWHERE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...CERU/EVANEGO
AVIATION...LAMBERT
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1121 AM CST SUN FEB 23 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 301 AM CST SUN FEB 23 2014
CURRENTLY AS OF 09Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED RIDGING FROM THE EASTERN PACIFIC INTO ALASKA...A BROAD UPPER
LOW OVER THE CANADIAN ARCHIPELAGO...AND BROAD TROUGHING ACROSS ALL
OF SOUTHERN CANADA INTO THE UPPER MIDWEST. SHORTWAVES OF NOTE FOR
THIS FORECAST INCLUDE ONE OVER WEST CENTRAL BRITISH COLUMBIA...ONE
OVER CENTRAL ALBERTA...AND THE LAST AS PART OF THE UPPER LOW ON THE
WESTERN SIDE OF THE CANADIAN ARCHIPELAGO. A NORTHWEST 925MB FLOW
CONTINUES TO GRADUALLY DRAW COLDER IN OUT OF CANADA TOWARDS THE
FORECAST AREA...NOTED BY THE 00Z MPX SOUNDING AT -15C. THAT SAME
SOUNDING ALSO CONTINUES TO DEPICT PLENTY OF DRY AIR...RESULTING IN
CLEAR SKIES EARLY THIS MORNING. COMBINATION OF THE CLEAR SKIES AND
COOLING 925MB TEMPS HAS ALLOWED TEMPERATURES TO DROP INTO THE SINGLE
DIGITS ABOVE ZERO. IF THE 5 TO 15 MPH BREEZE WAS NOT PRESENT TO KEEP
THE AIR MIXED...TEMPERATURES WOULD PROBABLY BE A LOT COLDER.
OVERALL LITTLE CHANGE IS PROGGED BY MODELS TO OCCUR IN THE NEXT 24
HOURS IN TERMS OF THE UPPER LEVEL PATTERN OVER THE UPPER MIDWEST AND
THE FORECAST AREA. WE STILL REMAIN UNDER THE INFLUENCE OF A DRY
NORTHWEST LOW TO MID LEVEL FLOW...WHICH SHOULD HELP KEEP SKIES
MAINLY CLEAR THROUGH TODAY AND MUCH OF TONIGHT. THERE ARE SOME
INDICATIONS OF CIRRUS APPROACHING LOCATIONS WEST OF THE MISSISSIPPI
RIVER LATE TONIGHT...BUT THATS REALLY ABOUT IT FOR CLOUDS.
925MB TEMPS TODAY ARE FORECAST TO RANGE BETWEEN -13 AND -16C...ABOUT
1-2C COLDER THAN YESTERDAY. THEREFORE...WE SHOULD SEE HIGHS JUST
SLIGHTLY COOLER THAN YESTERDAY. SKIES STAYING CLEAR THROUGH
MUCH OF TONIGHT PLUS 925MB TEMPS FALLING TO -14 TO -19C...COLDEST
OVER WISCONSIN...SHOULD ALLOW FOR LOWS IN MOST LOCATIONS IN THE
SINGLE DIGITS BELOW ZERO. AGAIN...THERE LOOKS TO BE A PERSISTENT
NORTHWEST BREEZE THROUGH TONIGHT HELPING TO PREVENT DECOUPLING.
STILL...THE TYPICAL COLD SPOTS COULD TRY TO APPROACH -10F. WIND
CHILLS LOOK TO GET CLOSE TO ADVISORY CRITERIA...BUT TOO MARGINAL AT
THIS POINT TO ISSUE AN ADVISORY.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 301 AM CST SUN FEB 23 2014
THE 2 MAIN IMPACTS REMAIN FOR THE LONG TERM...
1. POTENTIAL FOR SOME SNOW LATE MONDAY AFTERNOON AND NIGHT
2. THE BITTER COLD AIR...ESPECIALLY TUESDAY NIGHT AND BEYOND.
REGARDING IMPACT NUMBER 1...THE SHORTWAVES CURRENTLY OVER CENTRAL
BRITISH COLUMBIA AND ALBERTA REMAIN PROGGED TO PHASE TOGETHER OVER
THE DAKOTAS ON MONDAY...THEN QUICKLY SLIDE THROUGH THE FORECAST AREA
AROUND 06Z TUESDAY. MOISTURE IS LACKING FOR THESE SHORTWAVES...WITH
PRECIPITABLE WATER CLIMBING TO 0.1-0.2 OF AN INCH. HOWEVER...SOME
WEAK ISENTROPIC LIFT ON THE 275-280K SURFACES COMBINED WITH DPVA
AHEAD OF THE SHORTWAVES SHOULD BE ENOUGH TO SQUEEZE OUT SOME LIGHT
SNOW. SNOW SHOULD BE SOMEWHAT FLUFFY...THOUGH THE BULK OF THE LIFT
LOOKS TO OCCUR ABOVE THE DENDRITIC GROWTH ZONE. TIMING WISE...MODELS
CONTINUE TO SLOW DOWN THE SNOW MOVING INTO THE AREA...WITH THE
23.00Z NAM/GFS/CANADIAN/ECMWF KEEPING MUCH OF THE SNOW WEST OF THE
AREA PRIOR TO 00Z TUESDAY. ITS MORE OF A MONDAY NIGHT SNOW NOW. DID
RAISE CHANCES UP FOR MONDAY EVENING WEST OF THE MISSISSIPPI RIVER
WITH GOOD MODEL AGREEMENT FOR THE SNOW THEN. AFTER 06Z MONDAY...
MODELS DIVERGE ON HOW MUCH SNOW MIGHT BE LEFT WITH THE 23.00Z
GFS/CANADIAN DRY WHEREAS THE NAM AND ECMWF STILL HAVE SOME SNOW
LEFT. SPLIT THE DIFFERENCE AND HAVE SOME 20-30 PERCENT CHANCES FOR
NOW. IT APPEARS MUCH OF THIS HAS TO DO WITH THE TIMING OF THE PHASED
SHORTWAVE.
NOW IMPACT NUMBER 2...THE COLD. IN THE WAKE OF MONDAY NIGHTS
SHORTWAVE TROUGH...925MB TEMPS FALL TO -15 TO -20C. A SECOND AND
MORE POTENT COLD SURGE REMAINS PROGGED TO PLUNGE INTO THE AREA
TUESDAY NIGHT...DROPPING 925MB TEMPS TO -23 TO -25C BY 12Z
WEDNESDAY. THIS SURGE IS BEHIND THAT SHORTWAVE CURRENTLY OVER THE
CANADIAN ARCHIPELAGO. WIND CHILL ADVISORIES SEEM ALL BUT LIKELY
TUESDAY NIGHT INTO WEDNESDAY MORNING. A BRIEF BOUT OF WARM ADVECTION
IS SUGGESTED FOR WEDNESDAY AHEAD OF AN ARCTIC COLD FRONT
DROPPING SOUTH OUT OF CANADA...THOUGH IT APPEARS A BRISK WEST WIND
WILL ACCOMPANY IT. THEN ITS BACK TO THE COLD AS ANOTHER IMPRESSIVE
SURGE OF ARCTIC AIR DIVES SOUTH INTO THE REGION FOR THURSDAY ON
SOME BRISK NORTHWEST WINDS. 925MB TEMPS FROM THE 23.00Z GFS AND
ECMWF DROP TO -23 TO -27C BY 12Z THURSDAY...WHILE 850MB TEMPS
APPROACH -30C ACROSS OUR NORTH. THESE READINGS ARE NEARLY 3 STANDARD
DEVIATIONS BELOW NORMAL. BEYOND THURSDAY...MODELS BEGIN TO DIVERGE
A BIT WITH THE HANDLING OF THE COLD AIR. THE 23.00Z GFS TRIES TO
MODIFY THE COLD AIR SOMEWHAT FROM THE FLOW BECOMING MORE ZONAL
ACROSS THE NORTHERN TIER OF THE U.S.. THE 23.00Z ECMWF ALONG WITH
EXTRAPOLATION OF THE CANADIAN HAS THAT SAME ZONAL FLOW...JUST A
SMIDGE FURTHER SOUTH...WHICH RESULTS IN A CONTINUATION OF THE DEEP
FREEZE. FOR THE FORECAST LEANED A BIT CLOSER TOWARDS THE ECMWF.
OVERALL FOR TEMPERATURES TUESDAY THROUGH SATURDAY...STAYED CLOSE TO
A CONSENSUS OF 30 DAY BIAS CORRECTED GUIDANCE...WHICH PERFORMED WELL
IN PAST COLD SPELLS THIS WINTER. THURSDAY NIGHT COULD BE VERY COLD
WITH A SURFACE RIDGE PARKED OVERHEAD. WOULD NOT BE SURPRISED IF
SOME OF THE TYPICAL COLD SPOTS TO APPROACH -30F.
GIVEN HOW DEEP SOME OF THE FROST IS ALREADY...WATER MAINS UNDER
ROADS WILL NEED TO BE WATCHED CLOSELY. LUCKILY THE HIGHER SUN ANGLE
CAN HEAT THE TOP OF THE ROAD SURFACES MORE NOW THAN IN JANUARY...BUT
STILL THIS COLD AIR WILL NOT BE GOOD. THERE ARE STRONG INDICATIONS
TOO FROM THE CFS THAT THE BELOW NORMAL WEATHER COULD PERSIST THROUGH
ALL OF MARCH.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1121 AM CST SUN FEB 23 2014
PLAN ON VFR CONDITIONS THROUGH THE PERIOD. HIGH PRESSURE
REMAINING ANCHORED ACROSS THE NORTHERN PLAINS THROUGH TOMORROW
WILL KEEP NORTHWESTERLY WINDS 10 TO 15 KTS AT THE TAF SITES. FOR
THIS AFTERNOON...25 KT GUSTS AT KRST DUE TO MIXING UP TO 925 MB
WILL SUBSIDE BY SUNSET. HOWEVER A TIGHT ENOUGH PRESSURE GRADIENT
WILL REMAIN IN PLACE TONIGHT TO KEEP BOUNDARY LAYER FROM
DECOUPLING. HIGH LEVEL CLOUDS AROUND 15 KFT SHOULD SPILL EASTWARD
OVER THE AREA LATE TOMORROW MORNING IN ADVANCE OF A PASSING
SHORTWAVE.
&&
.CLIMATE...
ISSUED AT 301 AM CST SUN FEB 23 2014
GIVEN ALL THE COLD AIR TO ROUND OUT THE MONTH OF FEBRUARY...HERE IS
HOW FEBRUARY AND THE WINTER WOULD STACK UP BASED ON THE CURRENT
FORECAST...
...FOR THE MONTH OF FEBRUARY...
LA CROSSE... 9.5 AVERAGE TEMPERATURE...4TH COLDEST
COLDER FEBRUARYS...
1873... 3.9
1936... 4.3
1899... 9.4
ROCHESTER... 6.9 AVERAGE TEMPERATURE...4TH COLDEST
COLDER FEBRUARYS...
1936... 0.5
1979... 5.7
1917... 6.0
...FOR THE WINTER...DECEMBER THROUGH FEBRUARY...
LA CROSSE... 11.6 AVERAGE TEMPERATURE...5TH COLDEST
COLDER WINTERS...
1872-1873... 8.4
1874-1875... 10.5
1977-1978... 11.4
1935-1936... 11.4
ROCHESTER... 8.9 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